The first models of universal horizontal boring machines appeared at the beginning of the last century. Today, having undergone a series of serious design changes, they have become productive, powerful and functional devices with a wide range of applications, the price of which is quite acceptable even for small enterprises.

Design features and advantages of universal horizontal boring machines

The main purpose of horizontal boring machines is deep boring of holes. Most often, they are used to manufacture gearbox and turbine housings, gearboxes and cylinder blocks, electric motors and other similar samples of parts and components for various industries mechanical engineering.

Speaking about the features of universal models of horizontal boring machines, it is worth noting the retractable spindle design and a cross-shaped rotary table. The retractable spindle has a more rigid structure than other similar types of milling equipment. This makes it possible to successfully perform high-precision machining of complex-shaped workpieces - cylinder blocks or beds - simultaneously along the entire length of a large part. The presence of a rear support post makes it possible to achieve excessive runout of the cutting tool, thereby compensating for the decrease in the intensity of its impact due to the maximum extension length of the spindle in the working position. This is especially important during the manufacturing process seats shaft bearings, gearboxes, housings and gearboxes, where it is necessary to ensure equal impact along the entire length of the workpiece.

To increase the functionality of the machines, a cross table of a rotary design is installed on them. Thanks to the presence of a rear stand, this technological solution allows you to simultaneously bore holes, for example for bearings, on opposite sides of the body workpiece when it is rotated 180 degrees. It was possible to cope with the problem of some loss of accuracy when moving the workpiece thanks to the technology of Hirth fastening on curved teeth and a two-gear system for rotating the table with pre-tensioned gearing.

An important advantage of universal machines is their adequate cost, which can be quickly compensated for in both small-scale and individual production, where non-standard models of parts, tools and structures are manufactured, and their repairs are also carried out. The only requirement that must be met when working on this equipment is the presence of highly qualified boring workers on the company’s staff. Otherwise, it is recommended to use CNC machines, which minimize the impact of the human factor.

Information about the manufacturer of horizontal boring machine 2620

The manufacturer of horizontal boring machines models 2620, 2620A, 2622, 2622A is Leningrad Machine Tool Plant named after. Sverdlova, founded in 1868.

Since 1949, it has been a heavy machine tool manufacturing enterprise. Began producing metal-cutting machines of his own design (horizontal boring, jig boring, copy milling, machining center type, etc.

In 1962, the Leningrad Machine Tool Production Association was created on the basis of the plant.

The association has a closed technological cycle, has foundry, procurement, galvanic production, all types of mechanical processing, bench assembly of machines, painting and packaging areas.

2620, 2620A, 2622, 2622A horizontal boring machines. Purpose and scope

The production of machines models 2620 and 2622 was mastered in 1957; they have a similar kinematic diagram and design. The machines have a more advanced design compared to the previously produced model 262G .

Machines models 2620, 2620A, 2622 and 2622A ( overall size) are designed for processing body parts that have precise holes connected to each other by precise distances.

The machines can perform: drilling, boring, countersinking, reaming holes, turning ends with a radial support (models 2620 and 2620A), milling with face mills and cutting internal threads with a boring spindle, as well as threading with a radial support (models 2620 and 2620A) with longitudinal movement table.

Operating principle and design features of the machine

Depending on the requirements for reading and setting by coordinates, the machines have two versions:

• with optical device (2620, 2622)
• with precise electric stop mechanism (2620a, 2622a)

Heaviest weight workpiece (with uniform distributed load on the machine table) 2000 kg.

The electric stopping mechanism allows you to re-set coordinates along the stops with an accuracy of up to 0.05 mm, which in a significant number of cases eliminates the need to use expensive jigs when processing batches of repeating parts.

Modifications of horizontal boring machine 2620

• 2620A, 2620E, 2620D, 2A620-1, 2A620F1, 2A620F11, 2A620F2, 2A620F2-1- factory produced machines "Sverdlov";
• 2620V, 2620G, 2620VF1, 2620VF11, 2620GF1- production machines Ivanovo Heavy Machine Tool Plant IZTS;
• 2A620-2, 2A620F1-2, 2A620F20-2- production machines Charentsavan Machine Tool Plant.

Versions of horizontal boring machine 2620

• 2620 And 2620A have radial caliper with built-in faceplate And normal retractable spindle with a diameter of 90 mm and are more versatile. They are primarily intended for work that requires the use of a radial support when turning end surfaces and when cantilever boring large diameter holes.
• 2622 And 2622A have reinforced retractable spindle with a diameter of 110 mm without a radial support, they are distinguished by increased rigidity and vibration resistance of the spindle system and have an advantage over other machines for work that does not require the use of a radial support.
• 2620 And 2622 have optical screens(graduation value 0.01 mm) are primarily intended for work in mechanical and tool shops when it is necessary to obtain increased coordinate accuracy
• 2620A And 2622A have vernier scale(division value 0.05 mm) and precision electric stop mechanism Designed for widespread use in machine shops.

Advantages of the 2620 horizontal boring machine

The production of machines models 2620 and 2622 was mastered in 1957; they have a more advanced design compared to the model 262G. The machines have a similar kinematic diagram and design.

Compared to the previously produced model 262G, the machine model 2620 has the following features:

1. More high rigidity machine due to the larger width of the bed, the cross-section of the front post, rotary table, sled, the width of their guides and the diameter of the boring spindle, the use of more precise bearings with preload;
2. For increased rigidity and precision the machine has mechanisms for clamping the rotary table, the rear rack, the steady rest, the upper transverse table slide, the lower longitudinal table slide on the bed guides, the spindle head on the front rack guides and the boring spindle on the tail guides of the spindle head;
3. Increased vibration resistance machine thanks to improved spindle supports, a shorter tail section of the spindle head and the use of a balanced main electric motor;
4. More high accuracy processing parts on a machine by reducing the manufacturing tolerances of the main parts of the machine, increasing the wear resistance of rubbing surfaces, using an indicator stop for the rotary table, a precision electric stop mechanism for the spindle head and cross sled, or an optical measuring system;
5. Increased spindle speed(from 1000 to 2000 rpm) and main electric motor power up to 10 kW;
6. Advanced feed range(from 2.2 to 1760 mm/min) by adjusting the speed of the electric motor direct current;
7. Stepless change in feed rates;
8. Available separate electric motor, which can be used to quickly turn the table;
9. Applied single-handle selective mechanism with a pulse device for switching with a handle 20 speeds of rotation of the spindle and faceplate;
10. Available locking the selective gear shift mechanism with an electric variator 19 to change the speed of minute feeds, as a result of which the feeds for each revolution of the spindle (or faceplate) when their rotation speeds change remain unchanged;
11. Special mechanical and electrical interlocking devices protecting the machine from incorrect switching on;
12. Provided automatic feed shutdown at extreme positions of the table and spindle head.
13. Increased level mechanization and more convenient machine control;

Technical characteristics of the machine:

• Boring spindle diameter: 90 mm
• Maximum axial movement of the spindle: 710 mm
• Maximum vertical spindle travel: 1000 mm
• Working surface table: 900 x 1120
• Maximum weight of the workpiece: 2000 kg
• Maximum movement of the radial caliper: 170 mm
• Number of rotation speeds of the boring spindle: 23
• Spindle speed limits: 12.5 - 2000 rpm
• Number of faceplate rotation speeds: 15
• Faceplate speed limits: 8 - 200 rpm
• Spindle axial feed speed limits: 2.2 - 1760 mm/min
• Table and spindle head feed speed limits: 1.4 - 1.120 mm/min
• Caliper feed speed limits: 0.88 - 700 mm/min
• Main motor power: 7.5/10 kW

Dimensions of the working space of the horizontal boring machine 2620

Radial support faceplate boring machine 2620

General view of horizontal boring machine 2620

Arrangement of components of horizontal boring machine 2620, 2620A, 2622, 2622A

Location of the main components of the horizontal boring machine 2620

The general view and layout of the machine is shown in Fig. 32.

The main components of the machine are: bed 28, front stand 21, spindle head 22, table 10, rear stand 5 with steady rest 3, faceplate 13, radial support 14, cabinet 24 with electrical equipment, electric machine unit 25.

The parts to be processed are mounted on a rotary table 8.

The machining tool is placed either on mandrels fixed in the inner cone of the spindle 15, or on a tool holder mounted on a radial support 14. Tool intended for processing long holes, is installed in long mandrels (boring bars), the right side of which is fixed in the inner cone of the spindle 15, and the left side rotates (and can simultaneously move in the axial direction) in the liners of the steady rest 3.

The machine spindle moves to a given coordinate using the following two adjustment movements:

1. movement of the transverse slide 7 and the workpiece in the transverse (horizontal) direction. This displacement value is measured roughly (with an accuracy of 0.05 mm) using a ruler with a vernier 11 and more accurately (with an accuracy of 0.01 mm) using an optical screen 9;
2. vertical movement of the spindle head 22 and the processing tool. This displacement value is measured roughly (with an accuracy of 0.05 mm) using a ruler 18 and a vernier 17 and accurately (with an accuracy of 0.01 mm) using an optical screen 16.

When working on horizontal boring machines, the following types of feeds are used:

1. for processing cylindrical holes - axial feed of the spindle, and sometimes longitudinal feed of the table;
2. for milling the end surfaces of parts - by transverse feed of the table or vertical feed of the spindle head;
3. for processing the end surfaces of parts with a cutter, turning grooves or boring chambers in holes - radial feed of the caliper;
4. for cutting threads with a cutter - the axial feed of the spindle is equal to the pitch of the thread being cut.

Location of controls for horizontal boring machine 2620, 2620A

Location of controls for horizontal boring machine 2620

List of controls for horizontal boring machine 2620, 2620A

1. Start, reverse and stop spindle rotation
2. Spindle jog
3. Single-handle selective gear shifting
4. Turning the faceplate on and off
5. Starting and stopping the electrical unit
6. Start and stop feed
7. Selecting the feed amount with an electric variator
8. Starting fast movements
9. Starting installation movements
10. Installation for transverse movement of the table and vertical movement of the spindle head
11. Installation for longitudinal movement of the table
12. Moving the spindle head by hand
13. Longitudinal movement of the table by hand
14. Lateral movement of the table by hand
15. Installation rotation of the table by hand
16. Adjusting the position of the steady rest
17. Moving the rear pillar by hand
18. Moving the spindle by hand and setting the spindle to feed
19. Moving the faceplate radial support by hand and setting it to feed
20. Quick installation rotation of the table
21. Spindle clamp
22. Faceplate Radial Caliper Clamp
23. Headstock Clamp
24. Table cross sled clamp
25. Table sled clamp
26. Turntable Clamp
27. Rear pillar clamp
28. Steady rest clamp
29. Steady Rest Bushing Clamp
30. Portable remote control. Duplicates movements 121; 122; 126; 128; 129

Kinematic diagram of horizontal boring machine 2620, 2620A, 2622, 2622A

Kinematic diagram of horizontal boring machine 2620

Kinematic chain of the main movement drive. Since the cutting tool can be mounted on mandrels that are mounted in the spindle cone, and on the faceplate support, rotation can be imparted to both the spindle and the faceplate. In both cases, the two-speed electric motor M1, controlled from the remote control 11, through a kinematic chain with two three-crown blocks B1 and B2 rotates shaft IV with 18 frequency steps.

The kinematic scheme provides 36 possible gear ratios (2 x 3 x 3 x 2 = 36), but since 13 of them are repeated, the spindle receives 23 different revolutions per minute (from 12.5 to 2000).

Spindle rotation VI. From shaft IV, through a two-stage gear transmission switched by coupling Mf1, rotation is transmitted to shaft V and spindle VI. The spindle VI can move axially inside the hollow shaft V.

The faceplate has 15 different numbers rpm (from 8 to 200), since the top three gear ratio options are not used.

1. General structure of the machine

Machines models 2620, 2620A, 2622 and 2622A have a common basic design.

At the right end of the frame there is a fixed front post, along the vertical guides of which the spindle head moves.

At the left end of the bed there is a rear stand with a steady rest for supporting the boring bar when boring long holes.

Between the racks there is a unit - a built-in machine table, consisting of a longitudinal (lower) sled, a transverse (upper) sled and a rotary table.

The machines consist of the following components:

• node 1 - bed;
• node 2 - spindle head;
• node 3 - table;
• node 4 - rear pillar;
• node 5 - electrical equipment on the machine;
• node 6 - accessories;
• node 7 - optical devices;
• node 8 - electrical equipment.

All four models of machines have a wide unification of components and parts. The units: “Bed”, “Table”, “Rear stand”, “Electrical equipment” are the same on all machines. The “Spindle head” unit has its own design on each machine model. The “Optical devices” unit is available only on machines of models 2620 and 2622.

2. Design of machine components

bed

The bed is the main part used to attach the machine to the foundation and connects the machine components into a single whole.

The bed with wide guides has a closed box-shaped section with walls reinforced by a system of longitudinal and transverse stiffeners. The bed guides in the chip formation zone are covered with casings; The table and rear stand are located on the frame guides.

Front pillar has wide guides along which the spindle head moves vertically. The front stand, which absorbs significant forces during operation of the machine, as well as the bed, has high rigidity and vibration resistance. To balance the spindle head, a counterweight is located on the rear side of the rack, connected to the spindle head by means of cables passing through the blocks.

Machine feed drive mounted in a separate housing on the right side of the frame. The main drive unit is a flanged DC motor for feeding and accelerated idling of the working parts of the machine.

Headstock

The spindle head is an assembly unit consisting of the following interconnected separately assembled mechanisms and mounted inside and outside its body:

• 1) main movement drive;
• 2) spindle device;
• 3) faceplates;
• 4) the drive mechanism for moving the boring spindle and the radial support of the faceplate;
• 5) tail section;
• 6) management mechanisms;
• 7) gear oil pump for lubrication of the main movement drive mechanisms;
• 8) plunger oil pump for lubrication of guides and a number of mechanisms.

Main drive(Fig. 23) is powered by a two-speed electric motor alternating current power 10/7.5 kW.

Changing the rotation speed of the boring spindle and faceplate is done by moving the movable blocks of gear wheels of the gearbox and switching the poles of a two-speed electric motor.

The main drive gears are made of heat-treated alloy steel; high-speed wheels have ground teeth.

Spindle device of machines models 2620 and 2620A(Fig. 24) consists of a retractable boring spindle with a diameter of 90 mm, a hollow spindle and a faceplate spindle. The nitrided boring spindle moves inside heat-treated, high-hardness long guide bushes pressed into the hollow spindle.

The high surface hardness of the nitrided boring spindle and associated hollow spindle bushings ensures long-term preservation wear resistance and accuracy under operating conditions.

The faceplate with radial support is mounted on its own large-diameter spindle, rotating on precision tapered bearings, which are mounted in the front and intermediate walls of the spindle head housing.

An internal hollow spindle passes through the faceplate spindle cavity. The outer ring of the front precision cylinder roller bearing of the hollow spindle is placed in the spindle head of the faceplate. An inner bearing ring having a tapered bore is mounted on the front end of a hollow spindle.

The rear precision tapered roller bearings of the hollow spindle are mounted in the intermediate and rear walls of the spindle head housing.

Thanks to the use of small-sized precision bearings, the faceplate spindle and the hollow spindle have sufficient dimensions and rigidity in the absence of a console on the inner hollow spindle.

A helical wheel is mounted on the faceplate spindle to drive the rotation of the faceplate. Two gear wheels are mounted on the hollow spindle. big wheel serves to transmit high torques in the lower speed range.

A smaller wheel that meshes with a PCB wheel (which increases the smoothness of the drive) serves to transmit low torques in the upper speed range.

Spindle device of machines models 2622 and 2622A(Fig. 25) consists of a hollow spindle and a reinforced retractable boring spindle with a diameter of 110 mm.

The front precision cylindrical roller bearing of the hollow spindle is mounted in the front wall of the spindle head housing. The rear precision tapered roller bearings of the hollow spindle are mounted in the intermediate and rear walls of the spindle head housing. The main motion drive is similar to the drive of the 2620 and 2620A machines.

Faceplate with radial support for machines models 2620 and 2620A(Fig. 24). A radial caliper moves in the guides of the faceplate housing. The rack-and-screw drive of the radial caliper has a device for “selecting” the clearance, which eliminates radial play, which causes the caliper to slob when rotating the faceplate. The radial caliper of the faceplate is clamped using two screws on the end plane of the faceplate. The caliper has two profile T-shaped grooves for attaching tools The faceplate has a cylindrical seating surface for centering the milling head body.

The faceplate can rotate simultaneously with the rotation of the boring spindle or be disabled over the entire range of rotation speeds of the boring spindle, which is important for safety reasons. At the set speed stage, the number of revolutions of the faceplate is 1.58 times less than the number of revolutions of the boring spindle.

Machines models 2622 and 2622A with a reinforced spindle do not have a radial support. The front end of the hollow spindle of these machines has a special design for mounting the milling head on it.

The drive mechanism for moving the retractable boring spindle and the radial support of the faceplate (in machines models 2620 and 2620A) is kinematically connected to a DC electric motor through a vertical shaft. In machines models 2622 and 2622A, part of the mechanism that transmits movement to the faceplate support is missing.

Tail section secured to the rear end wall of the spindle head housing. In the tail section there is a slider for the retractable boring spindle.

The slider contains precision thrust ball bearings that absorb the axial forces of the boring spindle.

The longitudinal movement of the boring spindle is carried out by a rack and pinion gear.

On the front wall of the tail section housing there is a handle for clamping the boring spindle against axial movement. Clamping is carried out by a screw with a trapezoidal thread through a block that acts on the front journal of the rack and pinion screw.

The tail section housing is covered with casings on top.

The short length of the tail section increases the rigidity and vibration resistance of the machine during operation.

Control mechanisms. On the front part of the spindle head the main electrical panel and the handles of the control mechanisms are located.

Gear oil pump designed for centralized lubrication of mechanisms in the spindle head and tail section.

The pump is located in the oil tank on the right and end wall of the spindle head housing, behind the tail.

The pump is driven by an alternating current motor with a power of N = 0.25 kW, with a number of revolutions per minute n = 400.

Start and stop of the pump are electrically interlocked with the start and stop of spindle rotation.

To monitor the oil level in the spindle head, there is an oil indicator on the side wall of the pump tank.

To control the operation of the pump, there is a jet oil indicator located in the upper right part of the spindle head cover.

Plunger oil pump serves to lubricate the headstock guides. The pump is located on the spindle headstock and is driven by the vertical stroke of the headstock.

Table

The built-in rotary table of the machine is located on the upper sled, which has transverse movement along the lower sled. The lower sled moves longitudinally along the frame guides.

Inside the cavity of the lower sled there are mechanisms for transverse movement of the upper sled and rotation of the table around the axle.

The drive of the longitudinal and transverse movement of the table is carried out from a DC electric motor through a system of gear wheels and screw pairs. The fast installation rotation of the table is driven by a separate AC electric motor mounted on the lower sled.

The guides and mechanisms of the lower sled are lubricated by a plunger pump mounted on the side wall of the lower sled.

The plunger pump is operated by hand.

The pump has a distribution valve for supplying oil to a closed guide lubrication system or to open system lubrication of mechanisms.

The rotary table guides, the upper sled and the rotation gear mechanism are lubricated from a similar plunger pump mounted on the side wall of the upper sled.

The table rotation angle is measured using a circular scale with 0.5° divisions marked on the bottom of the rotary table.

The table rotation angle is counted every 90° using a built-in indicator device with an indicator scale of 0.01 mm.

Rear pillar

The rear stand of the machine is located at the left end of the bed.

A steady rest with a hinged hinged lid moves along the vertical guides of the rear pillar. Replaceable bushings are inserted into the mounting hole of the steady rest to support the boring bar when boring long holes. The rest moves vertically (simultaneously with the spindle head) from a common longitudinal running shaft located along the bed (rear shaft). To accurately adjust the vertical position of the steady rest axis relative to the spindle axis, there is a correction device. When the hexagon of the correction device is turned, the steady rest lifting nut rotates and, moving vertically along the steady rest lifting lead screw, changes its position relative to the spindle axis.

Electrical equipment on the machine

The installation of electrical equipment on the machine and the electrical circuit are described in the second part of this manual.

Accessories

The accessories included in the kit and the cost of the machine are supplied according to the equipment list.

3. Kinematics of the machine

Main movement chain (Fig. 23 and 24)

The rotation drive of the retractable boring spindle (and the faceplate with radial support of the 2620 and 2620A machines) is carried out from a two-speed flanged AC motor through the gearbox gears.

Changing the rotation speeds of the boring spindle and faceplate with radial support is achieved by switching:

• a) small triple block of gears 4, 5, 6;
• b) a large triple block of gears 9, 10, 11;
• c) gear coupling 14 wheels;
• d) two-speed electric motor from 1,420 to 2,840 rpm.

When the gear pair 14, 15 is turned on, the boring spindle rotates in the lower speed range - from 12.5 to 630 rpm.

When the gear coupling 14 of the wheel with wheel 337 is engaged, the spindle rotates (through a gear pair 16, 17) in the upper speed range - from 800 to 2,000 rpm.

When the gear coupling 152 is engaged with the ring gear of the wheel 18, rotation is transmitted through the gears 18, 19 to the faceplate.

The retractable boring spindle has 23 rotation speeds - from 12.5 to 2,000 rpm. The radial support faceplate has only 15 rotation speeds - from 8 to 200 rpm.

In machines models 2622 and 2622A, due to the absence of a faceplate with a radial support, rotation from the pre-spindle shaft 153 (Fig. 25) is transmitted only to the rotation chain of the retractable boring spindle, which has 22 rotation speeds - from 12.5 to 1600 rpm .

Changing the direction of rotation of the spindle and faceplate is done by reversing the main electric motor.

Feed chain (Fig. 26)

The drive of working feeds and installation slow and fast movements of moving units is made from a flange electric motor operating in a DC drive system with a wide speed range of 1: 1,600. From the electric motor, rotation is transmitted to a gear pair 20, 21 with a central fuse that protects the feed chain from overload. The central fuse clutch transmits rotation to the distribution shaft 154. When there is an overload in the feed chain of any of the moving parts of the machine, the gear 21 (the driving part of the clutch) during rotation presses out the conical rollers of the traverse 155, as a result of which an axial movement of the traverse occurs, acting on the limit switch, and supply shutdown.

From the distribution shaft 154, rotation through a series of gears (when the corresponding handles are turned on) is transmitted in five different directions:

• 1) on the lead screws for the vertical movement of the spindle head and steady rest;
• 2) on the lead screw for the transverse movement of the table;
• 3) on the lead screw for the longitudinal movement of the table;
• 4) through the vertical shaft to the lead screw for axial movement of the boring spindle;
• 5) through the vertical shaft to the rack and pinion gear for the radial movement of the faceplate support.

Kinematics of movements of moving units

1. Vertical movement of the spindle head and steady rest

The gear coupling 156 is brought into engagement with the end teeth of the bevel wheel 22 (for reverse - with the wheel 23).

Through wheels 25, 26, 27, rotation from shaft 154 is transmitted to lead screw 28, which moves the spindle head through the lead nut. To move the rear rack rest, rotation is removed from the bevel wheel 27 and further through the wheel 30 and the shaft 157 running along the frame, fed to the gears 31, 32, 33, 34 (located in the rear rack sled) and the lead screw 35 (see kinematic diagram, Fig. 21 or 22). The spindle head and steady rest move simultaneously.

2. Transverse movement of the table

The gear coupling 159 (Fig. 26) is brought into engagement with the end teeth of the bevel wheel 46 (for reverse - with the wheel 48). Through shaft 160 (Fig. 26) and gears 49, 50, 51, 52, 53 (see kinematic diagram, Fig. 21 or 22), rotation from shaft 154 (Fig. 26) is transmitted to lead screw 56 (Fig. 21 and 22), which through the running nut carries out the transverse movement of the table. Clutches 156 and 159 are engaged by lever 130 (Fig. 28). When the lever 130 is rotated around the axis of the shaft 167, the sector 162 rotates, which, through the wheel 163, the eccentric 164 and the driver 165, moves the clutch 156 to the right or left. When turning the lever 130 around the axis of the shaft 339 through the sector 166, the shaft rack 167, the wheel 168 and the eccentric 169, the driver 170 will move the clutch 159 to the right or left. This single-handle device allows you to switch the vertical feed of the spindle headstock to the horizontal feed of the table and vice versa, as well as carry out simultaneous movement of both moving units when milling along the contour. The principle of milling without stopping the feed, when changing the direction of movement, reduces the ledges on the milled plane.

3. Longitudinal movement of the table (Fig. 27)

The gear coupling 158 is engaged with the end teeth of the wheel 40.

Through gears 41, 42, 43, rotation from shaft 154 is transmitted to the lead screw 44, which, through the lead nut, carries out longitudinal movement of the table.

4. Axial movement of the boring spindle (Fig. 29 and 31)

Vertical shaft 161 (Fig. 26) removes rotation through a pair of bevel wheels 46, 47 from shaft 154 and then transmits movement through a worm pair 68, 69 (Fig. 29) to shaft 171 located in the spindle head housing. A gear coupling 172 is attached to the right end of shaft 171.

A gear 84 is introduced into engagement with the coupling 172 (Fig. 29), which transmits rotation to the screw 91 through the gear 85, shaft 775, gears 87, 88, 89, 90 (Fig. 31); the latter, through a screw rack 92 attached to the slider, carries out axial movement of the spindle.

To turn on the wheel 84, it is necessary to set the steering wheel handle 138 (Fig. 32) to position III. The movement of the wheel 84 to the right and its engagement with the coupling 172 (Fig. 29) occurs by means of a gear sector 174 (Fig. 32), a circular double-sided rack 175, wheels 176, 177, a sector 178 and a driver 179. Disconnecting the wheel 84 from clutch will occur if the steering wheel handle 138 is set to position II. In this position, when the steering wheel rotates, rapid axial movement of the spindle occurs by hand. From the steering wheel through gears 100, 101, 104, 105, 106, 86 (Fig. 82), rotation is transmitted to shaft 173 (Fig. 29 and 31). Next, through the wheels 87, 88, 89, 90 (Fig. 31) and the screw pair 91 and 92, axial movement is transmitted to the spindle.

Turning the steering wheel handle 138 (Fig. 32) to position I allows you to perform fine axial movement of the spindle by hand when rotating the steering wheel. In this case, the gear 84 engages with the worm wheel 103 with its left end teeth (Fig. 29 and 30). Rotation from the steering wheel through gears 100, 101 (Fig. 32), a worm pair 102, 103 (Fig. 29 and 30) and then through a chain of wheels 84,85, 87, 88, 89 and 90 is transmitted to the screw pair 91, 92 In this position of the steering wheel handle, the hinge key 180 (Fig. 32) through the rack 175, wheel 176, gear sector 181, driver 182a and coupling 183 will come out of the groove of the bevel wheel 104 and disconnect the kinematic chain from the gear pair 104, 105.

The spindle movement count dial 182 receives rotation through gears 86, 106, 107, 108 and a worm pair 109, 110.

5. Radial movement of the faceplate support (Fig. 29, 33)

The vertical shaft 161 (Fig. 30), passing through the spindle head, transmits rotation through a worm pair 68, 69 to the shaft 171.

Together with the shaft 171, the gear coupling 338 rotates. With the coupling 338 (Fig. 29), a gear 70 is engaged, which through gears 71, 72, 73, 74, 75, 77 transmits rotation to the wheel 78, which is freely seated on the hub of the faceplate. Next, the rotation from the wheel 78 (Fig. 24) is transmitted through the gears 79, 80, 81 to the screw pair 82, 83. The screw rack 83 is attached to the faceplate support and thereby carries out its radial movement on the faceplate. To turn on the radial feed of the faceplate support, the steering wheel handle 139 (Fig. 33) should be set to position II. Through the gear sector 184, the circular rack 185, the gears 186, 187, the sector 188 and the driver 189, the wheel 70 will move to the left, where it will engage with the clutch 338 (Fig. 29); in this case, through the rack 190 (Fig. 33), the hinge key 191 rotates, which turns off the rotation of the steering wheel handle.

Disconnection of the wheel 70 from the clutch 338 (Fig. 29) will occur if the steering wheel handle 139 (Fig. 33) is set to position I. In this position of the handle, through the wheels 93, 94, 95, 70 the faceplate caliper is moved by hand.

The dial for counting the radial movement of the faceplate support receives rotation through a gear pair 96, 97 (Fig. 29).

Radial movement (feed) of the caliper (for turning the end surface) occurs when the faceplate rotates.

The radial feed mechanism of the caliper has a planetary device that provides equalizing movement in the kinematic drive chain when the feed is turned off.

The planetary device consists of a carrier 192, which receives rotation from the spindle through gears 19 and 76. On the carrier, a block of satellite gears 73 and 74 rotates freely on the axis.

The planetary device allows you to turn on and off the radial feed of the caliper with a rotating faceplate.

In machines models 2622 and 2622A without a radial support, the support feed mechanism is correspondingly absent (Fig. 30).

The kinematic chains of the mechanisms for rotating the table and moving the rear rack are shown in Fig. 21 and 22; Due to the simplicity of the design, the circuits are not described.

4. Machine control

Movement control is carried out from the main console on the spindle head and remotely from a lightweight portable backup console.

Special mechanical and electrical interlocks protect the machine from possible erroneous switching on. The machine control system does not require heavy physical effort on the part of the operator and reduces auxiliary time.

Rotation

Start, reverse and stop the rotation of the spindle and faceplate are carried out by buttons 121 (Fig. 19 and 20) on the main and portable consoles.

The push (installation) rotation of the spindle and faceplate is carried out on the same remote control using buttons 122.

Setting to turn on and off the rotation of the faceplate (only on machines models 2620 and 2620A) is done with handle 124.

Switching the speeds of the spindle and faceplate is carried out by a single-handle mechanism 123 of centralized control with selective installation at a given speed, with a special automatic reversible pulse device that protects the ends of the teeth from wear during switching.

Description of the gear shift mechanism (Fig. 35)

Changing spindle speeds is accomplished by switching two triple blocks of gears, a gear coupling and electric motor poles to turn it on at 1,500 or 3,000 rpm.

The translational movement of the blocks of gears 4, 5, 6 and 9, 10, 11, as well as the gear coupling 14, is carried out by drivers 193, 194, 195 from gears 196, 197 and 198 of the single-handle mechanism.

Gear 199 is mounted on the same shaft as wheel 196 and meshes with a pair of racks 200.

The gear 201 is mounted on the same shaft with the wheel 197 and is in mesh with a pair of racks 202.

Gear 203 is mounted on the same shaft as gear 198 and meshes with a pair of racks 204.

The position of each of the triple blocks and the gear coupling is determined by the relative position of the corresponding pair of racks of the switching mechanism.

Along the concentric circles of the selector disk 205 there is a series of through holes alternating in a certain sequence with gaps.

When the selector disk 205 moves forward from position II to position I (“on the racks”), the racks 200, 202, 204 move, and with them the gear blocks and gear coupling. If a hole is located against any protruding rack on the selector disk , then when the disk moves forward, the unit controlled by this rack will not switch.

The spindle speed is selected by turning the retracted handle 123 and, accordingly, the selector disk 205 around their axis according to the table of revolution numbers 206 on the front side of the cover. The speed indicator 207 is fixed to the disk 205 and rotates with it. It is possible to turn the disk only in its extreme left position II, when it has left the area of ​​racks 200, 202, 204.

When the handle 123 is moved 180° from position I to position II, the selector disk moves forward “away from the racks.” To do this, in the groove of the handle 123 there is a gear 208 engaged with the rack 209, which is attached to the selector disk 205. The wheel moves the rack and selector dial.

The roller 210 performs two functions: when the disk 205 is in position II, then the roller 210 enters the hole of the disk with a receiving cone and fixes the position of the disk in each of its 23 positions. When the disk is rotated from one position to another, the locking roller with spring 211 clicks through the locking holes. In this case, lever 212, resting against the end recess of the roller 210 through the plunger 213, does not allow the contacts B of the limit switch ZVPS to turn on (see electrical diagram, Fig. 6, part II).

This position corresponds to turning on the electric motor at 1500 rpm. In a number of positions of the disk, the locking roller 210 (Fig. 35), resting its end against stop A, will move in the direction of arrow B when spring 211 is compressed. In such positions of the disk, under the action of spring 214, the limit switch ZVPS, plunger 213 and lever 212 move and allow contacts B of the limit switch ZVPS close. In this case, the electric motor will turn on at 3000 rpm.

You can switch speeds either with the spindle stationary or without turning off its rotation at idle speed, and in the second case there is no need to stop the spindle before starting the switching, since the main motor is switched off and braked automatically during the speed switching process.

At the beginning of the retraction of the handle 123 (from position I to position II), the latch 215 releases the disk 205, and with it the roller 216, from fixation in the axial direction. Under the action of pulse spring 217, roller 216 will move along arrow D by the amount of pulse stroke D and release lever 218 and plunger 219. As a result, the engine control circuit will open (contacts E of limit switch 2VPS) and engine braking will begin if it was turned on. With further retraction of the handle 123, the disk 205 will begin to move away from position I to position II and will release the stop 220, the lever 221 and the plunger 222. The entire system, under the action of the spring 223, will compress the spring 224 (weaker) of the limit switch 1VPS and open the contacts G. When open contacts E and G, the engine stops. When the switching is complete, these contacts close and turn on the engine to normal operation. If, during the switching process, the ends of the teeth of any of the wheels of the moving blocks rest against the ends of the teeth of the wheel that is fixed in the axial direction coupled with it, the selector disk 205 will stop in its movement on the racks 200, 202, 204. With continued pressure on the handle 123, the gear wheel 208 will roll along rail 209, will overcome the force of the impulse spring 217 and tighten the roller 216. The washer sitting on the roller 216, through the lever 218 and the plunger 219, will close contact E of the 2VPS switch. In this case, the engine will be pulsed and the drive unit will rotate, the ends of the teeth of which rest against the ends of the teeth of the driven wheel. When the drive wheel turns, the impulse spring 217 will engage the block. At this moment, disk 205 will again be able to move, and spring 217 will open contact E.

According to the adopted switching scheme, the impulse torque of the electric motor is limited to the value necessary to rotate the leading part of the kinematic chain with frontal contact of the ends of the teeth. If, when the ends of the teeth contact under a large pressure angle, the moment of resistance to rotation of the driving or driven part of the chain is greater than the impulse torque developed by the electric motor, the latter will “overturn.” In this case, the device automatically performs a periodic reversal of the rotation of the electric motor through a time relay. in the direction of the pulse torque, the leading part of the kinematic chain will rotate and the gear block will be brought into engagement. Automatic periodic reversal of the electric motor with a reduced torque stops when the delay in bringing the block into engagement is eliminated. After the complete completion of the switching cycle, the electric motor automatically switches from the reverse mode to the normal rotation mode. Decrease in value impulse torque is achieved by introducing an ohmic resistance into the stator winding circuit.

Switching gears in motor reverse mode (at “sluggish” mechanical characteristics the latter) occurs with low relative speed sliding of the end surfaces of the teeth at permissible contact stresses. Thanks to this, a significant increase in the durability of the tooth ends is achieved.

The speed switching mechanism is kinematically connected through gears 225, 226, 227 to an electric feed variator 127, which changes the rotation speed of the feed drive DC motor.

Thanks to this connection, when changing the number of spindle revolutions per minute, the feed rate in mm per revolution is automatically maintained constant when the feed rate per minute is actually changed through the slide switch 228.

Speed ​​change order

• 1. Without turning off the rotation of the spindle (and faceplate), move handle 123 180° until it stops. In this case, simultaneously with the withdrawal of the handle, the electric motor will automatically turn off (with countercurrent braking).
• 2. By rotating the handle (retracted 180°, all the way) around the horizontal axis, select the desired speed using indicator 207.
• 3. By moving the handle in the opposite direction to the withdrawal, the gears are switched.

At the moment of complete switching, the electric motor is automatically turned on again.

In the event of a switching delay when the ends of the teeth of the moving gear blocks are mutually abutted, a special pulse device automatically performs a pulse rotation of the electric motor in reverse mode and turns it off again when the delay ends.

When switching, do not press the handle too hard or hit it.

A possible delay in the switching process is caused by the activation of the time relay to reverse the electric motor.

ATTENTION!

• 1. Care must be taken to ensure that the braking action of the main motor during switching is correct. In the absence of braking or malfunction of the latter, the ends of the teeth can quickly wear out or breakage may occur.
• 2. When turning the handle (retracted 180° all the way) to select the speed, the selector disk should not touch the ends of the mechanism rails. In case of incomplete retraction and, as a result, the ends of the racks touching the holes of the selector disks, the ends of the racks may break.
• 3. When switching speeds, you must be guided by the instructions in the table located on the front cover of the spindle head.

Moving the moving parts of the machine

All working feeds and installation movements are produced by a separate DC motor, the rotation speed of which can be electrically varied.

The DC generator is mounted in the unit, the start and stop of which is carried out by buttons 125 (Fig. 19 and 20) located on the main console. There are also buttons on the remote control and a key 126 for turning the feed on and off, a button 128 for turning on quick (setting) movements and a button 129 for turning on the setting feed. Buttons 140, located on the lower sled of the machine, are used for quick installation rotation of the table from an alternating current electric motor. Buttons 126, 128 and 129 are duplicated on the second portable remote control 150.

The following controls are used to set each of the moving bodies to the appropriate movement.

• 1. Handle 130. When turned to the right or left, the spindle head is set to move vertically up or down; When turning “towards you” or “away from you”, the table is set to move transversely “toward you” or “away from you”.
• 2. Handle 131 is used to set the longitudinal movement of the table.
• 3. Handle 138. When you press to the extreme position “from yourself,” the spindle is set to feed (see section “Moving moving parts by hand”).
• 4. Handle 139. When you press to the extreme position “from yourself,” the faceplate support is installed on the feed (see section “Moving the moving parts by hand”). Changing the feed direction of the spindle, headstock, table and faceplate support is done by reversing the feed motor using buttons 126.

The headstock and table, in addition to reversing by the engine, have a mechanical reverse of movement from the lever 130 to enable contour milling (see description of the operation of the feed mechanism on page 52).

The electric variator 127 selects the feed rate of the spindle headstock, the table along and across, the spindle and the radial support in mm per revolution of the spindle or faceplate. The feed amount may change during the cutting process. The electric variator can also select the speed of installation movements.

Moving movable organs by hand

To move the moving parts of the machine by hand, use following devices:

• 1. Shank 132 is used to move the spindle head vertically. The scale of the handle dial disk has a division value of 0.025 mm. One revolution of the dial disk corresponds to 3 mm of movement of the spindle head.
• 2. Shank 133 is used for longitudinal movement of the table. The scale of the dial disk has a division value of 0.025 mm. One revolution of the dial disk corresponds to 2 mm of longitudinal movement of the table.
• 3. Shank 134 is used for lateral movement of the table. The scale of the dial disk has a division value of 0.025 mm. One revolution of the dial disk corresponds to 3 mm of lateral movement of the table.
• 4. Shank 135 is used for installation rotation of the table.
• 5. Adjustment of the position of the rear rack steady rest to align the steady rest axis with the spindle axis is carried out using handwheel 136.
• 6. Shank 137 is used to move the rear pillar.
• 7. Axial movement of the spindle is carried out by handles 138 of the steering wheel. The handle has three positions: 1) middle; 2) “to yourself” and 3) “from yourself”. When you press the handle “from yourself,” the spindle is set to mechanical feed (see paragraph 3 of the section “Moving moving parts”). With the handle 138 in the middle position, the steering wheel is installed to quickly move the spindle by hand. The scale of the dial disk has a division value of 0.5 mm. One revolution of the dial disk corresponds to 50 mm of axial movement of the spindle. When the handle is positioned 138 “towards you,” the steering wheel switches to finely move the spindle by hand. The scale of the dial disk has a division value of 0.02 mm. One revolution of the dial disk corresponds to 2 mm of axial movement of the spindle.
• 8. The radial support of the faceplate is moved by hand using handle 139. This handle has two positions: “towards you” and “away from you”. In the “pull forward” position, the faceplate support is installed for feed (see paragraph 4 of the section “Moving moving parts”). In the “towards you” position, the steering wheel serves to move the radial caliper by hand. The scale of the dial disk has a division value of 0.1 mm. One revolution of the dial disk corresponds to 3 mm of movement of the faceplate caliper.

Feed variator (Fig. 36)

The feed variator is a two-row multi-stage slide switch. The position of the variator engines sets the rotation speed of the feed motor.

The variator is kinematically connected to the speed shift mechanism, due to which the feed values ​​on the table are expressed in mm per revolution with actual feeds in mm/min. The feed amount is set by electric variator 127. Together with the variator, pointers 229 and 230 are turned and, through rollers 231 and 232, a two-row slide switch 228 is turned.

The following devices are available for reading feed readings:

• 1. Outer disk - table 255 with a scale showing the feed amounts in mm in reverse.
• 2. Internal disk - table 234 with two indicators 229 and 230, rigidly connected to the variator handle 127. Indicators 229 and 230 show the feed rate in mm on the contrary with the actual “minute” feed. Therefore, if the machine has a spindle and faceplate rotating at different speeds , two pointers are required, showing the feed in mm per revolution of the spindle and the feed in mm per revolution of the faceplate.

In fig. 36 shows the following feed rates as an example.

1. The indicator 229 shown in FIG. 36,shows:

• a) 0.11 mm - the amount of feed of the headstock and table per one revolution of the spindle (outer row of the left side of table 234);
• b) 0.11 mm - the amount of feed of the radial caliper per one revolution of the faceplate (inner row of the left side of table 234).

2. Pointer 230 shows:

• a) 0.18 mm - spindle feed value per spindle revolution (outer row of the right half of table 234);
• b) 0.18 mm - the amount of feed of the headstock and table per one revolution of the faceplate (inner row of the right half of table 234).

Table 233 shows feed rates from 0.056 to 9 mm/rev. Feeds less than 0.056 and more than 9 mm/rev can also be obtained on the machine (but not at all spindle and faceplate speeds). With such feeds, indicators 229 and 230 will indicate the inscription “Feed less than 0.05” or “Feed more than 9”.

The machine passport contains graphs (Fig. 14, 15, 16 and 17) of the feed of all moving parts and the dependence on the number of revolutions of the spindle or faceplate.

If during operation you need to change the feed without changing the speed of the spindle or faceplate, then you should turn the variator 127 to the desired position. In this case, lever 235 will rotate together with roller 231. Ball 236 will click, fixing the selected position of the variator.

If it is necessary to change the number of revolutions of the spindle or faceplate without changing the set feed, this is done by turning the handle 123 of the gear shift mechanism. In this case, the following turns through gears 225, 226, 227:

• a) disk with table 233 (through key 237 and axis 238);
• b) table 234 with indicators 229 and 230 (through ball 236, lever 235 and roller 231);
• c) slide switch 228 (through ball 236, lever 235 and roller 232).

In this case, the position of the pointers relative to the table remains unchanged.

Feed activation procedure

• 1. Before turning on the feed or rapid installation movement, you must first press out the corresponding movable element.
• 2. Set the supply of the corresponding moving element by turning one of the handles 130, 131, 138 or 139 (Fig. 19 and 20).
• 3. Set the feed rate in mm per revolution using the variator 127.
• 4. Turn on the feed by pressing the feed buttons 126 on the remote control.

Clamps of moving parts of the machine

The clamps of the spindle headstock, transverse (upper) and longitudinal (lower) sleds, rear rack sled, turntable are centralized single-handled with clamping bars.

The spindle head is clamped to the front pillar guides by turning handle 143 around the longitudinal horizontal axis. The spindle head clamping device has two clamping wedges (moving along rollers), which are acted upon by an elastic bar, compressed by an eccentric on the axis of the handle 143.

The handle has two positions - upper and lower.

When the handle is turned up all the way, the headstock is forcefully clamped on the guides of the front pillar.

The power clamp is designed for use in roughing a product with a stationary headstock (rough boring of holes with a spindle and faceplate, rough turning of the ends with a radial support of the faceplate, rough milling with a transverse feed of the table, etc.).

When turning the handle 143 down all the way, locking clamping occurs with low force, providing “selection” of the gaps in the guides and eliminating the “dump” of the spindle head from the guides of the front pillar.

The fixing clip is designed for use in all types of precision (finishing) machining with a stationary headstock, as well as for roughing with vertical feed of the headstock (vertical milling).

The fixing clamp does not cause any noticeable deformation of the mating units and ensures a stable position of the spindle head on the front pillar guides.

The spindle clamp is a screw clamp; clamping is done by turning handle 141 all the way to the right. When released, the handle rotates to the left until the tension in the clamp is released. The radial support is clamped onto the faceplate using two screws 142 using an external hex key.

The table cross sled is clamped by turning the handle 144 to the right. When released, the handle rotates to the left until the tension in the clamp is released.

The same sequence is used for clamping and releasing the longitudinal sled with handle 145.

By turning handle 146 to the right all the way, the turntable is clamped, and by turning it to the left all the way, it is released.

Clamping the rear rack sled on the frame is done by turning handle 147 to the right.

Clamping and pressing of the rear pillar steady rest slider on the vertical guides is carried out with two 148 nuts using a wrench (5 = 30 mm).

The replaceable bushings in the steady rest are clamped and released using two nuts 149 using the same wrench.

In order to eliminate the influence of gaps in the guides on the accuracy of the machine, the clamping of the moving parts occurs in two mutually perpendicular planes.

5. Machine locks

Special mechanical and electromechanical interlocks protect the machine mechanisms from overload, as well as from erroneous activation. To eliminate the possibility of injury to the worker, the rotation of the handwheels is automatically turned off during working feed and rapid installation movement of the spindle and radial support.

It is impossible to simultaneously turn on the working feed of the spindle (or radial support) and the working feed of the upper table sled in the transverse direction or the spindle headstock in the vertical direction.

It is impossible to simultaneously turn on the working feed of the upper table sleds in the transverse direction and the spindle headstock in the vertical direction and the working feed of the lower table sleds in the longitudinal direction. When changing gears, the main motor stops automatically. When there are delays in switching gear blocks, the main engine performs a pulsed reverse rotation of the kinematic chain with a reduced starting torque.

If the gear shift lever is not locked, the main engine cannot be turned on.

When the feed drive is overloaded, the feed is automatically switched off.

The lubrication pump turns on when the main drive motor is turned on.

The transverse movement of the table is automatically turned off at the extreme positions of the upper (transverse) sled.

The longitudinal movement of the table is automatically switched off at the extreme positions of the lower (longitudinal) sled.

The vertical movement of the spindle headstock is automatically switched off in the extreme positions of the headstock.

The longitudinal movement of the rear pillar to the left is limited by a rigid stop.

The axial movement of the spindle is limited by electrical limit switches and when moving the handwheel by rigid stops.

The movement of the radial support of the faceplate in both directions is limited by rigid stops.

If one of the moving parts (spindle, headstock, table) collides with the electric limit switch on the main control panel, the brightness of the signal lamp decreases. In this position, turning on the mechanical supply of any movable organ is impossible.

Retraction of the movable organ from its final position should be done in one of the following ways:

6. Machine lubrication

The machine should be lubricated strictly in accordance with the attached lubrication diagram (Fig. 37 or 38).

Use oil grades only in accordance with the instructions in the lubrication diagram,

The lubrication of the machine is mainly carried out centrally. To lubricate the spindle head mechanisms, there is a gear oil pump driven by a separate electric motor. The amount of "Industrial 20" grade oil required to fill the spindle head is about 20 kg.

The vertical guides of the spindle headstock are lubricated by a plunger pump located on the spindle headstock and driven by the “stroke” of the headstock. The amount of “Industrial 45” grade oil required to fill the plunger pump tank is 0.6 kg.

Lubrication of the rotary table guides, upper and lower table sleds is carried out by two hand-driven plunger pumps. The amount of “Industrial 45” grade oil required to fill each pump is 2 kg.

Before starting work on the machine, swing the handle of each pump 10 times to fill the lubrication system.

The mechanisms of the faceplate, rear pillar and table are lubricated with wick, produced by a system of open tubes from group grease nipples.

The front bearing of the hollow spindle is lubricated once every 6 months with UTV grease (grease 1-13 fatty). Lubricant quantity 0.5 kg.

Used grease must be removed by washing.

Filter G41-12-0.2 is cleaned after disconnecting it from the lubrication system.

The operation of the gear oil pump is monitored using a jet oil indicator on the spindle head.

The amount of oil in the pump system is monitored using oil indicators, and in other lubrication areas - by inspection through the filler necks.






Precision electric stop mechanism for boring machine 2620




The precise electric stop mechanism of the table and spindle head (Fig. 93) is mounted on the spindle head body and the upper sled of the table and is activated when adjustable stops 2 are pressed on the lever of mechanism 1. The stops are installed on two-position rods 3 - vertical, attached to the front post, and horizontal, attached to the lower sled of the table.

When moving the spindle headstock in the vertical direction or the table in the transverse direction, lever 1, in contact with stop 2 mounted on rod 3, stops, compressing spring 7, and at the same time microswitch 10 is activated, the speed of movement of the spindle headstock or upper sled is reduced to 30 mm/ min, with which the movable body continues to move another 5-6 mm, after which a stronger spring 5 is compressed and microswitch 9 is activated, which turns off the feed.

When lever 1 moves through from bottom to top relative to stop 2, lever 1 rests on cone 4 and, turning on axis 6, moves away from stop 2.

When moving through from top to bottom, lever 1 also rotates around axis 6 thanks to the bevel at the bottom of the lever.

The stopping accuracy is determined by an 8-hour indicator and is equal to 0.03-0.04 mm.

Rod 3 consists of permanent and removable parts. The stops are fixed in grooves, rods and have micrometric screws for precise installation according to the mechanism indicator.

Rotation of the rod 3 to a certain position is carried out by a special handle. During the installation movements of the turntable and spindle head, rod 3 with stops 2 is installed in a position where the stops do not touch lever 1 of the precision stop mechanism.

The procedure for setting the precision stop mechanism depends on the size of the parts.

In a single production, the adjustment procedure is as follows: secure the removable rods, align the spindle axis with the axis of the first hole being machined, install the first pair of stops when their ends touch the lever of the precision stop mechanism, secure the stops, align the arrow of the stop mechanism indicator with the scale zero (by rotating the micrometric screws of the stops ), a set of measuring tiles is installed on the ends of the stops or pressed against the ends of the stops, the headstock or the upper sled of the table is moved until the indicator arrow coincides with the scale zero; the movable organs are clamped and the next hole is processed, etc.

In small-scale production, all stops are installed sequentially on rod 3 at specified coordinates, and then all holes are sequentially machined using customized stops and precise stopping mechanisms.

In large-scale production, the stops are accurately installed on the removable parts of the rods, the spindle axis is aligned with the axis of the first hole being machined, the removable parts of the rods are placed on the permanent ones so that the ends of the stops corresponding this hole, touch the lever of the precise stop mechanism, secure the removable parts of the rod with two or more screws depending on their length, using the threaded holes and grooves in the removable parts of the rod, and align the arrow with the scale zero by rotating the screw at the end of the rod.

2620, 2620A, 2622, 2622A horizontal boring machine. Video.




Technical characteristics of horizontal boring machines 2620

Parameter name	2620	2620V
Basic machine parameters
Diameter of retractable boring spindle, mm	90	90
Largest diameter of spindle boring, mm	320
The largest diameter of bore by the faceplate support, mm	600
Maximum length of boring and turning of the faceplate with a caliper, mm	550
The largest diameter of the drill (along the cone), mm	65
Table
Working surface of the table, mm	900 x 1120	1120 x 1250
Maximum mass of the processed product, kg	2000	3000
Maximum table movement, mm	1000 x 1150	1000 x 1120
Limits of table working feeds (lengthwise and crosswise), mm/min	1,4...1110	1,4...1110
Maximum table feed gain (lengthwise and crosswise), kgf	2000	2000
Dial scale division, mm	0,025
Table rotation dial scale division, degrees	0,5	1
Switching stops	There is
Speed ​​of fast movements, m/min	2,2
Speed ​​of fast installation circular movements, rpm	2,8
Spindle
Maximum horizontal (axial) movement of the spindle, mm	710	710
Spindle speed, rpm	12,5...2000	12,5...1600
Number of spindle speeds	23	22
Limits of spindle working feeds, mm/min	2,2...1760	2,2...1760
Limits of working feeds of the radial caliper, mm/min	0,88...700	0,88...700
Limits of spindle head working feeds, mm/min	1,4...1110	1,4...1110
Maximum vertical movement of the spindle head (installation), mm	1000	1000
Speed ​​of rapid movements of the spindle head, m/min	2,2
Speed ​​of rapid spindle movements, m/min	3,48
Faceplate rotation speed, rpm	8...200	8...200
Number of faceplate speeds	15	15
Ability to disable faceplate rotation	There is
Possibility of simultaneous feed of support and spindle	There is
Maximum movement of the radial support of the faceplate, mm	170	160
Speed ​​of rapid movements of the radial support, m/min	1,39
Maximum torque on the spindle, kgf*m	495	140
Maximum torque on the faceplate, kgf*m	780	250
Maximum spindle feed gain, kgf	1500
Maximum caliper feed gain, kgf	700
Maximum headstock feed gain, kgf	2000	2000
Slicable metric thread, mm	1...10	1...10
Cutable inch thread, number of threads per 1"	4...20	4...20
Drive unit
Number of electric motors on the machine
Main motion drive electric motor Power, kW	10	10
Main motion drive electric motor, rpm	3000	2890
Feed drive electric motor, kW	1,52	2,1
Table rotation drive, kW	1,7	2,0
Dimensions and weight of the machine
Dimensions of the machine, including travel of the table and slide, mm	5510 x 3200 x 3012	5700 x 3400 x 3000
Machine weight, kg	12000	12500

The search for the most rational designs of devices, combining small dimensions with ease of assembly and adjustment, has led to the widespread use in units and mechanisms of devices of complex design housings, boards, brackets and other parts containing a large number of holes of 1st and 2nd accuracy classes at strict tolerances not exceeding 0.01-0.02 mm for the relative position of the hole axes. The simplest and most reliable solution to the problem of processing conjugate systems of precision holes is the use of the coordinate boring method.
The development of this method and the creation of domestic jig boring machines were one of the most important factors that contributed to the achievement of very significant successes in the field of precision instrument making. Distinguished by their high accuracy and productivity, jig boring machines, along with their widespread use in tool shops, have also found application in production shops of instrument-making factories. Currently, the domestic machine tool industry equips the instrument-making industry with high-quality precision jig boring machines, however, along with domestic equipment, our factories also operate various models of imported jig boring machines ( machining centers ).

The use of various types of auxiliary and installation devices makes it possible to expand the capabilities of jig boring machines and widely use them not only for instrumental work (dies, molds, machine tools), but also for processing complex and precise parts in single and small-scale production.
There are two main types of jig boring machines:
- single column machines, the table of which receives two mutually perpendicular movements

2E450; 2E450AF10; 2E450AF30) which can be purchased from the company Stanochny Mir LLC;
- portal machines, the table of which receives longitudinal movement, and the spindle group, mounted on the crossbar, receives transverse movement.

According to the method of calculating coordinates, machines are divided into 3 groups:

1) Machine tools on which coordinates are measured using a ruler, lead screw, dial and vernier in combination with a so-called corrective device that corrects inaccuracy of the screw pitch along its entire length. The use of adjusting devices allows the use of machines large sizes with sufficient accuracy.

2) Machine tools on which coordinates are measured using gauge blocks and indicators. Lead screws These machines are not a means of measurement, but only serve to move the table. Machines of this group are manufactured only single-column.

3) Machines, the coordinates of which are measured using precise scales in combination with an optical device. These machines are a more advanced type of jig boring machines.

To work on jig boring machines, devices and accessories are used that increase the versatility of the machines and expand their technological capabilities. Depending on their purpose, they can be divided into the following groups:

Installation devices. The main purpose of these devices is to install and fasten parts. This type of device includes: squares, rectangular and box tables, horizontal and universal rotary tables, sinus table, etc. Rotary tables for cattle, in addition to fastening, provide the ability to rotate parts, due to which rotational adjustment is added to the longitudinal and transverse movements available on the machine movement.

Accessories for fastening parts

This group includes different types stands, prisms, all kinds of clamping strips, jacks, clamps, threaded rods, and fastening bolts with a set of nuts and washers, etc.

Fixing devices

With the help of which the location of the part is determined or the part is installed in the required position. These devices are used to set the base surfaces of the workpieces relative to the machine spindle.

Tool Mounting Accessories

These include eccentric chucks, adapter bushings, adapter conical bushings, mandrels, boring bars, universal chucks, tool holders for attaching cutters when boring large diameter holes, special chucks for turning, special chucks for milling, etc.

Boring machines are a class of industrial metalworking equipment that performs drilling and increasing the diameter of through or blind holes, as well as threading. These units are used for processing large-sized parts in serial or single-unit production.

This article presents boring machines. We will consider their functional purpose, operating principle and design features, and also provide an overview of popular equipment models.

Read also: what is it and how does it work?

1 Boring machine - capabilities, operating principle

A group of boring units have a characteristic feature: their spindle, fixed in a horizontal (less often vertical) plane, makes axial movement towards the workpiece. A working tool is fixed in the spindle seat, the type of which directly determines functionality machine

Modern boring units are capable of performing the following technical operations:

• boring;
• countersinking;
• drilling;
• thread cutting (internal and external);
• turning;
• milling (face and cylindrical);
• trimming ends.

In fact, these machines are universal multifunctional equipment that can fully replace several metalworking installations.

The key parameter of any boring machine is the diameter of the spindle carrying the main working tool. Depending on it, all units are classified into three groups: small (diameter 50-125 mm), medium (100-200 mm) and heavy (200-320 mm).

Spindle rotation is the main movement of the machine, while the feed movement, depending on the design features of the equipment, can be communicated either to the workpiece or cutting tool. The movement of the tool can be axial, radial or vertical; the movement of parts occurs due to the movement of the work table.

1.1 Design features

Depending on the design features, all boring units are divided into two groups: horizontal and vertical. The most common is a vertical boring machine; let’s consider its typical design using the popular model 2E78P as an example.

• working spindles (1, 2, 3, 4, 5);
• control unit (6);
• electrical panel (7);
• load-bearing column (8);
• desktop (9);
• base (10);
• reading device (11);
• twin gearbox and feeds (12);
• spindle head (13);
• workplace lighting (14);
• electrical equipment control panel (15).

A characteristic feature of the 2E78P finishing and boring machine is the ability to install replaceable spindles different diameters- 120, 78 and 48 mm, which increases the diameter of the holes being bored. The cutters are fixed on the spindle by means of a clamping screw, and a center finder is mounted in the hole located at the end of the cutting head of the spindle (in 2E78P an indicator type center finder is used). The center finder is an auxiliary tool in the form of an overhead template that allows you to accurately align the axes of the cutter and the hole being bored.

The 2E78P work table consists of two blocks: the lower slide, moving transversely along the frame guides, and the table panel itself, moving longitudinally along the slide. There is a ruler on the front wall of the panel for precise positioning of the table. Its installation and movement are performed manually using flywheels.

The spindle head is one of the key components of the unit; it consists of a motor, a spindle, and a V-belt drive connecting them. Inside the headstock housing, the ribs of the housing form an oil bath in which the rotating shafts are located.

A gearbox is installed on the finishing and boring machine 2E78P and other models of medium and heavy units. In this model, it provides 12 spindle rotation speeds and 4 spindle head working feed speeds. An overrunning clutch is also provided for accelerated movement of the headstock directly from the drive.

All boring machines are equipped with overload-resistant asynchronous motors; commutator motors can only be found in low-quality Chinese equipment. The 2E78P model has 3 engines, one of which is responsible for moving the spindle head, the second for its accelerated movement, and the third for moving the work table.

2 Types of equipment

The entire variety of boring machines, depending on the functional purpose and design features, is classified into the following types:

• drilling and boring;
• boring and surfacing (mobile and stationary);
• milling and boring;
• turning and boring.

Drilling and boring machines were previously the most common group of equipment that could be found in any metalworking shop, but now most drilling operations are performed on milling equipment, which is why the use of such units has decreased. Depending on the area of ​​application, they are divided into universal and specialized (for mass production of a specific part).

A boring and turning machine is usually used for processing planes and holes inside hull structures. Such equipment is often called coordinate equipment, since it allows you to achieve high precision location of holes relative to the plane base surface. In addition to standard functionality, these units can perform marking operations.

The mobile boring and surfacing machine differs significantly from the mechanisms considered. This is a portable piece of equipment used to repair and rebuild cylindrical holes on large machinery. Such units can operate in any location and spatial position, which makes them indispensable in the field of automotive, ship and aircraft construction.

Let us separately highlight diamond boring machines, a characteristic feature of which is the use of carbide cutters coated with diamond, allowing the processing of workpieces made of hardened steel. Such units are often used for high-precision boring car parts— connecting rods, bushings, cylinders, etc.

2.1 Overview of the 2A6622F4 machine (video)

2.2 Popular models of boring machines

One of the most common vertical boring units is the 2E78P model, which the Maikop Machine Tool Plant has been producing from 1982 to the present day. This equipment is also capable of performing milling operations for parts made of steel, cast iron and non-ferrous metals.

Let's consider technical characteristics 2E78P:

• diameter of bored holes - from 29 to 200 mm;
• drilling diameter - up to 15 mm;
• maximum dimensions of processed parts: 75*50*45 cm, weight - up to 200 kg;
• desktop dimensions - 100*50 cm;
• drive power - 2200 W;
• spindle speed - 26-120 min.

Among the horizontal equipment, we highlight the 2A622F4 machine, manufactured by the Leningrad Machine Tool Plant named after. Sverdlov. This unit is equipped with CNC - numerical control, which significantly expands its functionality.

The CNC allows you to program the automatic movement of the working mechanism along four axes - X, Y, Z, W. There is also the possibility of manual control from the remote control. The machine uses a domestically developed CNC system - CNC 2C42, corresponding to automation class F4. The unit is equipped with an electronic display, which displays data about the operating mode of the machine.

Technical characteristics of model 2A622F4:

• diameter of bored holes - from 15 to 250 mm;
• drilling diameter - up to 50 mm;
• maximum dimensions of processed parts: 100*100*125 cm, weight - up to 5000 kg;
• desktop dimensions - 125*125 cm;
• drive power - 20,000 W;
• spindle speed - 4-1250 min.

This is large-sized equipment for industrial use, aimed at use in single and mass production. The dimensions of the machine are 398*634*398 cm, weight - 20 tons. Among the operational advantages of this unit, we highlight the presence of high-speed hydraulic clamps that automatically fix the workpiece, the device of the spindle assembly on precision bearings and the use of telescopic guides.

Boring machines are intended for processing parts in single and serial production. These are highly versatile machines that can be used to perform rough and fine boring of holes, turning of external cylindrical surfaces, the ends of holes, drilling, countersinking, reaming, milling planes, threading and other operations. A wide variety of different types of processing performed on boring machines allows, in some cases, to carry out complete processing of a part without moving it to other machines.

Depending on the nature of the operations performed, purpose and design features, boring machines are divided into universal and specialized. In turn, universal machines are divided into horizontal boring, jig boring and diamond boring (finishing boring). For all types of machines, the most significant parameter that determines all the main dimensions of the machine is the diameter of the boring spindle. A characteristic feature of boring machines is the presence of a horizontal spindle, which makes an axial feed movement. The spindle holds a cutting tool: a boring bar with cutters, a drill, a countersink, a milling cutter, a tap, etc.

The forming movements in boring machines are spindle rotation and feed movement. The feed is communicated to either the tool or the workpiece, depending on the processing conditions. Auxiliary movements are the installation movements of the spindle head in the vertical direction, the movement of the table in the longitudinal and transverse directions, the movement of the rear rack with the steady rest, the movement of the steady rest along the rack, etc.

Figure 39 shows general form horizontal boring machine. On the bed 1 stand installed 2 , on the vertical guides of which the spindle head is mounted 3. Its body contains mechanisms that carry out the main movement and feed. The gearbox spindle is hollow, a faceplate is attached to it 4. A caliper is installed in the radial guides of the latter 5 , carrying a cutter. A boring spindle is mounted inside the hollow spindle 6. If necessary, the end of a boring bar is inserted into the conical hole of the latter, the left end of which is held in the rest 7 rear pillar 8. The steady rest is located coaxially with the spindle and can move in the vertical direction synchronously with the spindle head.

A table is used to install and secure workpieces , consisting of three elements: slide 10, moving along the bed 1 , carriages 11 , having a feed in the transverse direction and a rotating work table 9 .

The main movement is the rotation of the faceplate or boring spindle. The feed movement, depending on the nature of the processing, is received by the part (table) or tool (caliper) 5 , boring spindle or spindle head.

The jig boring machine is designed not only for machining holes with high precision, but also for obtaining accurate center-to-center distances. The machine can measure linear dimensions and center-to-center distances. The spindle and table of the machine have independent drives. The spindle is driven by an adjustable DC motor.

Fig.39. General view of the universal horizontal boring machine

Figure 40 shows a vertical diamond boring machine designed for fine boring of cylinder bores in a car or tractor engine block with a diamond tool or carbide cutters. This machine has a massive, rigid structure that reduces vibrations caused by high-speed rotating mechanisms.

Fig.40. Diamond boring machine

On the foundation slab 1 cabinet is mounted 2 , and on it there is a vertical frame 3. There are T-shaped slots on the front of the plate for securing the table 4. On the stove inside the cabinet 2 An electric motor is installed to drive the main movement. Pumps for coolant and lubricant, as well as electrical equipment, are installed inside the cabinet. Inside the bed 3 gearboxes and feeds are placed, and in front, on its outer upper part, a spindle head is fixed 5 . Along two straight guides 6 vertical frame can be moved bracket 7 with spindle 8.

From the electric motor through the V-belt drive, gearbox and flat-belt drive, the machine spindle with the boring bar receives six different frequency values. The spindle with boring bar is adjusted to different rotation speeds using replaceable gears of the gearbox.

The feed box is also an independent unit, mounted inside the frame in its upper part. In addition to the mechanism for switching the working feeds of the spindle with the boring bar, the feed box contains mechanisms for rapid feed and automatic switching of the spindle from rapid approach to working feed, as well as to accelerated return to its original vertical position.

Using the rotary tables and other accessories supplied with the machine, you can also machine holes specified in the polar coordinate system, inclined and mutually perpendicular holes, and grind end surfaces.

The jig boring machine is equipped with optical devices that allow you to count the whole and fractional parts of the coordinate size. The machine can be used both in tool shops and in production shops for precise machining of parts without special equipment. Under normal operating conditions, the machine ensures the accuracy of setting center-to-center distances in a rectangular coordinate system of 0.004 mm and in a polar system - five arc seconds.