SU1733171A1 - Method and apparatus for production of ball-bearing races - Google Patents

Abstract

The invention relates to metal forming, including chip removal and rolling profiling in the manufacture of rings, mainly ball bearings. The goal is to increase the durability of the rolling tool and the quality of the rings. Before rolling, the end portion of the tubular billet is machined and an annular groove is made. A threaded tubular billet secured in one of the clips 14 of the six-spindle swivel drum is moved to the rolling position. The rolling unit, including the separator 17 with three idle shafts 18, is moved to the left. At the same time, the plunger 21, by means of the rocker arms 23, which is loaded with the force of the compressed spring 30, informs the counter-movement of the plunger 22. The rollers 18, rolling with conical shanks with converging sleeves 31 and 32, move radially and deform the rotating tubular billet. At the end of the rolling, the sleeves 31 and 32 are diluted, then all the calipers are retracted and the drum is turned. The blank is fed to the next position to complete the profiling by removing chips and ring segments. Performing an annular groove on the machined billet prior to rolling allows the tool life to be increased by ensuring uniform distribution of the load on the roll forming section. 2 sec. and 3 z. p. f-ly, 13 ill. in

Description

The invention relates to metalworking, which includes profiling by removing chips and rolling in the production of rings, predominantly ball bearings from a pipe (tubular billet).

The aim of the invention is to increase the durability of the rolling tool by eliminating slipping of the rolls relative to the workpiece, increasing the degree of uniformity of the load distribution on the profiling part of the rolls along their axis, as well as improving the quality of the produced rings by increasing their geometrical accuracy,

Figure 1 shows the proposed device, the initial position; figure 2 is a view of And figure 1; on fig.Z - section bb in figure 2; 4 is a kinematic diagram of the rolling unit, the initial position; figure 5 - scheme of turning at the first technological position; figure 6 - scheme of turning at the second technological position; figure 7 - the position of the tool before rolling on the third position; Fig. 3 shows the kinematic scheme of the rolling unit, the operating position; figure 9 - rolling scheme at the third technological position; figure 10 is a diagram of the turning on the fourth position; in fig. 11 - scheme

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turning on the fifth technological position; in fig. 12 is a diagram of the separation of the ring at the sixth technological position; on Fig - position of the workpiece when based on the sixth technological position.

The method is carried out as follows. The pipe section is profiled by a chip removal operation, an annular groove and external chamfers are formed on the resulting billet, the outer surface of the ring is profiled by rolling, the inner surface of the rolled billet is bored and the product is separated from the pipe.

A device for manufacturing ball bearing rings comprises a frame 1 (FIG. 1), on which a rotary drum 2, housings 3, transverse supports 4-7 (FIG. 2), a central longitudinal support 8 (FIG. 1), rolling assembly 9 are placed. , kinematic connections in the form of mechanisms for feeding and clamping the pipe (tubular billet), turning and fixing the drum at technological positions, moving calipers, as well as driving, lubricating systems, cooling and controlling the process of manufacturing rings (not shown). In the rotary drum, 1 and 2) six spindles 11 are equally spaced circumferentially in the shims 10 (FIG. 3), each connected by means of a gear 12 to a central gear wheel 13 receiving rotation from the drive. Each spindle 11 houses the cage 14 in the form of a multilobe collet with a conical outer surface that is installed with the possibility of axial movement using a feed mechanism and clamping of the workpiece. The protective covers 3 are made in the form of hollow cylinders, covering the radial clearance pliers and mounted coaxially with the spindles 11 so that they can rotate together with the drum 2, the spindles form positions located along the process of making rings. These positions are supported by transverse calipers 4-7 (Fig. 2) and one central longitudinal caliper 8 (Figures 1 and 2). The calipers are mounted with the possibility of reciprocating movement by means of an appropriate mechanism: transverse calipers 4-7 are perpendicular to the axis of rotation of the drum 2, longitudinal caliper 8 is parallel to this axis along the guide rolling pin 15. The calipers are equipped with a cutting tool.

The rolling unit 9 (Fig. 1) includes a quill (16) (Fig. 4), a separator 17 with three idle rollers 18 (one is shown), a sleeve 19, an emphasis 20, a radial movement mechanism

rolls, containing the inner 21 and outer 22 plungers, the rocker 23 and the lock 24 of the separator. In the pintles 16, mounted coaxially with the yoke 14, two hemmers 25 are fastened and the central boring a is made. In the separator 17 there are nests for rolls 18 and a sleeve with which it is installed in bearings 25. The separator is equipped with an end cap 26 for quick tool change.

The roller 18 is a body of rotation, symmetrical about the transverse plane, having in its middle part the profiling section b, the reverse

formed on the ring, adjacent to it from two sides, tapered oppositely directed support shanks c and cylindrical spikes d at the ends, by means of which the roller is oriented in the radial grooves of the separator.

The sleeve 19 is installed in the bore b of the pinoli 16 with the possibility of axial movement and is equipped with a tapered hole e, eyelets f and a threaded axial hole e. The sleeve 19 also has longitudinal cuts (grooves) h (one is shown) and two coaxial holes in the eyelets f perpendicular to the axis of the sleeve, which is inserted into the finger 27. In the tapered hole e

sleeve 19 is located without the possibility of rotation on the key (not shown) of the expansion wedge 28, made in the form of a cone, in which the tension screw 29 is installed, installed without the possibility of axial movement

relative to the sleeve.

The stop 20 is provided with a collar i, a groove with a bevel J, a thread with which it is installed in the hole g of the sleeve 19, and a recess under the spring 30.

Removable pressure sleeves 31 and 32 are fixed at the ends of the plungers 21 and 22 with tapered holes covering the shanks from the rolls 18. Rigidly fixed at the opposite ends of the plungers

staples k and I, forming transverse grooves. The inner plunger 21 is rigidly fixed on the longitudinal caliper 8 (figure 1) with the help of the bracket 33 (figure 4).

The quill 16, the inner 21 and the outer 22 plungers are mounted coaxially with the possibility of axial movement relative to each other on the keys (not shown). Yoke 23 mounted on a finger 27

in the lugs f, the sleeves 19 rotatably (sway) and interact with the brackets k and I by means of rollers 34 and 35 mounted on axes parallel to the geometric axis of the finger 27. The geometrical axes of all three hinges of the rocker arms 23 are located in the same plane at equal distances x apart.

The lock 24 of the separator is designed to provide a fixed axial position of the rolls during the rolling process and is made in the form of a two-armed lever hinged on the frame 1 and equipped at the ends with rollers 36 and 37, as well as a spring 38. The roller 36 has the ability to interact with the bevel j of the stop 20, and the roller 37 with the cam 39 mounted on the inner plunger 21.

The surface m of the bed 1 is the clamping stop for the separator during the rolling process. Production cycle control is automatic.

The position of the parts of the device in FIG. 1 and A is taken as the reference.

In the rotary spindle drum 2 (Fig. 2), the processed tubular blanks clamped in cages 14 rotate,

The transverse supports 4-7 are retracted from the spindles of the drum 2 to their extreme positions. The longitudinal caliper 8 (Fig. 1), together with the rolling unit 9, is retracted from the end of spindle drum 2. The force from the compressed spring 30 (Fig. 4) through the stop 20 and the sleeve 19 is transmitted to the finger 27 (axis of the middle joint of the rocker arm) and then through the rocker arm 23 and rollers 34 and 35 of the plungers 21 and 22, respectively. Since the plunger 21 is rigidly connected by means of the bracket 33 to the longitudinal support, the force transmitted by the roller 34G is relieved by the movement mechanism of this support (not shown). The rocker 23, loaded by the upper hinge roller 34, by the lower hinge roller 35 acts on the clamp I of the plunger 22, pressing its protrusion n to the end of the internal plunger 21. At the same time, the pushing sleeves 31 and 32 of the plungers are retracted axially from the shanks from the rollers 18, enclosing them with tapered holes with a radial gap, spaced at equal distances from the transverse plane of symmetry of the rolls.

The expansion wedge 28, held by the tension screw 29, acting on the bevels (tapered surface) e, expands the part of the sleeve 19 provided with longitudinal cuts h, creating a tension g between the sleeve and the quill 16, reliably fixing their mutual position.

The cam 39, acting on the roller 37, holds the lever of the lock 24 of the separator in the upper position, while the spring 38 is compressed, and the roller 36 is retracted from the stop 20.

The middle hinge of the rocker arms 23 is connected with the separator 17 through the sleeve 19, the quill 16 and the bearings 25.

The device works as follows.

Drive, lubrication and cooling system pumps (not shown) are included.

Transverse 4-7 and longitudinal 8 (figure 2)

calipers are moved using the appropriate mechanisms in the direction of technological positions, first quickly, and then with a working speed.

0 At all positions, the blanks are simultaneously processed in accordance with the technological process as follows.

At the first technological position

5, the end portion of the workpiece 40 (Fig. 5) to be profiled is machined with a pass 41 and a boring 42 lathe incisors fixed on a longitudinal caliper, turning to remove surface inner and outer defective (decarbonized) layers.

On the second in the course of technological

5, the process positions on the workpiece 43 (FIG. 6) form an annular groove o and external chamfers p and q using a shaped circular cutter 44 mounted on the transverse support 4 (FIG. 2).

The depth of the grooves g is taken from the conditions of the formation of an annular bridge between the body of the tubular workpiece clamped in the cage and the section to be shaped which ensures the transmission of the torque torque without destruction. Finally, the depth of the groove is determined empirically in accordance with a particular treatment mode.

The profiling of the outer surface of the ring by rolling is carried out at the third technological position.

The rolling unit, carried away by the bracket 33 (Fig. 4), first moves to the left without changing the axial position of the plunger 5 and 21 and 22 and the rocker arms 23 relative to each other.

The idle rollers 18 (Fig. 7) span the rotating workpiece 45, are moved apart by it in the radial direction, producing a zero twist around their axes.

When the shoulder i of the stop 20 (Fig. 8) is stopped by the surface m of the base 1, the separator 17 will be set to a position in which the transverse plane of symmetry

5 of each roll 18 (FIG. 17) is equidistant axially from the borders of the section of the workpiece that is separated by the groove.

With further movement of the longitudinal caliper 8 (FIG. 1) with the operating speed, the interaction of parts of the rolling unit occurs according to FIG. 8.

After the cam 39 comes out from under the upper roller 37, the lock 24 is rotated by means of the spring 38, the lower roller 36 is lowered into the groove of the stop 20 and abuts on its bevel J, fixing the axial position of the stop reliably, and therefore, the separator connected with it by rolls 18 and thumb 27 of the rocker arm 23,

Further movement of the longitudinal caliper together with the internal plunger 21 is accompanied by rotation of the circle 23 around the middle of its fixed hinge fixedly and, as a result, simultaneous counter displacement of the external plunger 22 at a speed equal to the speed of the plunger 21. The last circumstance is explained by the equality of the shoulders and the parallel arms the axes of its hinges in the same plane, i.e. the arrangement of the centers of the hinges on one straight line, in which the projections of the oppositely directed velocity vectors of the centers of the extreme hinges onto the common geometrical axis of the plungers are equal to each other. As a result of the interaction of the conical shanks with the corresponding conical surfaces of the pressure sleeves 31 and 32, the rolls 18 radially feed (approach) the rolls 18. The rollers 18, when in contact with the outer surface of the rotating tubular workpiece 45, begin to run around the supporting internal conical surfaces of the sleeves 31 simultaneously with the radial movement and 32, having made a planetary motion, carries the separator with it. As a result of the started rolling, the outer surface of the grooved-separated section of the billet acquires a shape corresponding to the profile of the rolls 18 (Fig. 9). At the same time, the moldable area is partially broadened, partially enlarged in diameter due to the heaving of cylindrical bands adjacent to the groove. Upon reaching a predetermined rolling depth controlled by the stroke of the plungers, the longitudinal support is stopped and, after one or two turns of the tubular billet relative to the separator, is quickly retracted. At the beginning of the outlet, the separator 17 (Fig. 8) and the finger 27 of the middle hinge of the rocker arms 23 held by lock 24 , remain fixed, the inner plunger 21, moved with the longitudinal caliper, rotates the beam around the middle hinge; the outer plunger 22 is displaced in a direction opposite to the plunger 21 by means of a lower hinge coupled thereto; the grommets 31 and 32 are synchronously retracted from the shanks from the rolls 18, restoring the original radial clearance.

The cam 39, acting on the roller 37, returns the lock lever 24 to its original position, the lower roller 36 goes out of engagement with the bevel j of the stop 20. From this moment the stop 20 is held in a stationary position by means of the spring 30. When the axial clearance s between the end face plunger

0 21 and the protrusion p of the clamp I of the plunger 22 decreases to zero, the displacement of the plungers relative to each other is stopped and the entire assembly receives displacement along with the longitudinal support. The spring 30 is compressed using the stop 20, the idle rolls 18, moving with the separator 17, interact with the rolled profile, shifting from the center. After the longitudinal slide is retracted, the rolling unit is in the initial position according to FIG. 4.

At the fourth technological position, the blank 46 (Fig. 10) is bored into the inner surface in order to eliminate wets using a boring cutter 47,

5 mounted on a longitudinal caliper, as well as trimming the end face with a scoring tool 48 mounted on a transverse caliper 5 (FIG. 2).

At the fifth technological position in the blank 49 (Fig. 11), internal chamfers with a radius of 4.6 mm are turned with a shaped circular cutter 50 fixed on a longitudinal slide with the possibility of movement in the axial and transverse directions. When the longitudinal slide is supplied, the cutter 50 stops at the dot-dashed position depicted in FIG. 11 using a fixed stop (not shown), not obstructing further

0 move the caliper. The radial cutter 50 is moved using the stop t located on the transverse support 6 (FIG. 2).

In the sixth position from the workpiece 51

5 (FIG. 12) is separated by means of a cutting cutter 52 mounted on a transverse support 7 (FIG. 2), a ring 53 (FIG. 12), which then enters the discharge tray (not shown). With the help of the feeder and

0 clamping the workpiece at the same position establish a sliding stop 54 (Fig. 13), move the workpiece 51 in the axial direction, based on the stop 54, clamped in the holder 14, return the stop.

5 After all the calipers have returned to their initial position, the drum 2 (Figures 1 and 2) is set, rotating in the direction of the round arrow, to the position at which the workpieces fall under the action of others with a tool in accordance with the technological process.

All parts of the device return to their original position and the command to repeat the cycle is automatically given.

Thus, the simultaneous processing of all blanks fixed in the spindle and drum is performed.

The device provides for the possibility of adjusting the axial position of the rolls 18 (Fig. 4) by changing the length of screwing in the stop 20.

An important condition for the operation of the device is the symmetry of the axial position of the rolls 18 relative to the pressure taper sleeves 31 and 32, ensuring favorable conditions for their contact, excluding the mutual skew of the axes. This symmetry is established when adjusting the device using the mechanism of the axial position of the separator.

To do this, rotating the tension screw 29 (Fig. 4), partially removing the wedge 28 from the orifice of the sleeve 19, eliminating the tension between the pin 16 and the sleeve 19. Install the special templates (instead of the rolls 18) into the separator 17 instead of the axial clearance. not shown), differing in shape from the roll by the presence of a collar in the middle, symmetrically located relative to the ends. Turning the yoke 23, clamping the flanges of the templates between the ends of the tapered sleeves 32 and 31. Tighten the tension screw 29, restoring the tension between the quill 16 and the sleeve 19, reliably fixing their mutual position. Set in the separator rolls instead of templates.

Structurally, it is possible to coaxially install the separator 17 (Fig. 4) and the yoke 14, which is carried out during adjustment (not shown).

The plastic deformation region of the rolled pipe section is limited to the proximal end of the preform and the adjacent groove wall. At the same time, approximately the same conditions of plastic flow of the metal in both directions from the formed trough occur, contributing to the simultaneous termination of the formation of the beads. This is accompanied by a uniform distribution of the load along the roll and a uniform wear of its profiling part. The ability to remove the defective layer before rolling allows the hardened surface layer obtained by rolling to be maintained, resulting in an increase in wear resistance. In this way, the durability of the rolls and the quality of the surface to be profiled are improved.

Supplying the cage with the drive of its rotation in combination with the placement of the mill rolls in the separator with the possibility of free (idle) rotation allows

apply torque directly through the body of the rotating tubular billet. At the same time, at the moment of the start of rolling, idle rolls and a separator having a significantly smaller mass in comparison with the mass of the tubular billet receive a twist. This is accompanied by a slight slip, which practically does not reduce the uniform durability of the rolls during the standard period.

5 of their service.

The use of several idle rolls and the proposed scheme for their loading reduces the working load on the rolling tool. This is explained by

It is possible to reduce the maximum diameter of the profiling part of the rolls, as not requiring installation of the supports, but to be freely placed in the separator, and therefore, to reduce the length of the arc of the contact in the plastic deformation zone between the roller and the workpiece.

The use of several rolls makes it possible to elastically deform during rolling the billet in the form of an oval

0 a polyhedron, not an ellipse, this reduces the magnitude of alternating stresses in the wall of the workpiece and eliminates the need for a mandrel (less deflection).

5 In the proposed roll loading scheme, the radial rolling forces are closed on the plungers, balancing each other, are not transferred to the frame, which allows the rolling unit to be made compact and placed on a longitudinal support.

The compactness of the assembly is also facilitated by the installation of plungers on one side of the yoke in one support.

Use of rocker arm associated

5, the middle axis of the swing with the separator, and the extreme axes with the plungers, makes it possible to constructively simply carry out synchronous radial movement of all the rolls at the same time.

0 Execution of the rocker equal-arm and

the arrangement of its axes in the same plane allows it to be produced at the same speeds, thus eliminating the possibility of axial skewing of the rolls. If at least one of the two last conditions is not observed (location of the roll axes in the same plane, equality of the arms of the rocker arms), inevitably displacement of the plungers at different speeds, the rolling process is impossible (unless the

rolls with different tapers or other non-rational bypass measures).

Installing the plungers on the longitudinal slide eliminates the need to use a separate drive for the mechanism of radial movement of the rolls, which also contributes to simplifying the design of the device.

Equipping the separator with an axial position mechanism including a sleeve with bevels and a wedge mounted for movement and interaction with the sleeve bevels allows the axial position of the rolls to be set with high precision when setting up the device and reliably reproduce it in each processing cycle.

Based on the proposed method, the process of manufacturing the inner ring of a single radial ball bearing of an average series of diameters of type 308 GOST 8338-75 made of steel grade SH-15 has been developed.

The pipe billet (tube) has the following dimensions, mm: length 3000; outer diameter 54.8; inner diameter 38.4. The ring separated from the tubular billet has a width of 23.2 mm, an internal diameter of 39.65 mm, internal chamfers with a radius of 4.6 mm, an external rolling profile consisting of a groove with a radius of 7.61 mm and a minimum diameter of 50.73 mm adjacent to cylindrical stitches (flanges) with a diameter of 56.4 mm, two chamfers 1.5x45.

The device uses a cutting tool in the form of lathe tools and a rolling tool in the form of three rolls with a maximum diameter of a core of 27 mm.

The frequency of rotation of all spindles is 162 rpm. The processing time at the rolling position is 8 s.

Claims (5)

Claim 1. Method for manufacturing ball bearing rings, including profiling a pipe section using chip removal, rolling operations, forming an annular groove and separating the ring from the pipe, characterized in that, in order to increase the durability of the rolling tool and the quality of the rings, the groove form before rolling, and rolling is done after removing chips from the outer and inner surfaces of the pipe. 2. A device for manufacturing ball-bearing rings from a pipe, containing transverse calipers with tools for chip removal and rolling, a holder for placing the pipe in the rolling position, rotatably mounted longitudinal caliper mounted for movement parallel to the axis of rotation of the holder, rolling unit comprising two rollers arranged with the possibility of radial movement, characterized in that it is provided with a drive for rotating the cage, at least one additional roller, a separator, Vum plungers with tapered holes at one end of each, installed with the yoke, rocker, connected with the middle hinge with the separator, extreme joints with the plungers, with rolls made with conical shanks that are installed with the possibility of interaction with the tapered holes of the plungers . 3. The device according to claim 2, characterized in that the rolling unit is located on a longitudinal support. 4. A device according to claim 2, characterized in that the rolling unit is provided with a mechanism for the axial position of the separator, including a sleeve with bevels and a wedge mounted with the ability to move and interact with the bevels of the sleeve. 5. The device according to claim 2, characterized in that the rocker is made with an equal length of arms. BEFORE fieL CJ I t I j -0 / Y 6Ј 9 gpf. ff o d i-w  //, & - / 77777UL j 8 gpf d zpp W V :: uh Phie. eleven 51 50 FIG. 12 54 N FIG. 13