JP5886659B2 - Processing method of cage - Google Patents

Description

  The present invention relates to a cage for a rolling bearing such as a needle roller bearing, in particular, a cage produced by punching a pocket, a rolling bearing using the cage, and a method for machining the cage.

  Needle roller bearing cages are usually manufactured by turning a steel pipe that has been cut into a predetermined shape by turning, or a workpiece that has been processed into a predetermined shape by deep-drawing a steel plate. Is manufactured by forming a required number of pockets for retaining rollers by punching.

  FIGS. 5A and 5B are examples of the cage manufactured in this way. The cage 1 includes a body portion 2 and inward flange edges 4 formed at both ends thereof, and a constriction portion 3 is formed at an intermediate portion in the axial direction of the body portion 2. Between the edges 4 is a shoulder 5. An axially long pocket 6 is formed in a range extending from one shoulder 5 to the other shoulder 5 through the constricted portion 3. The roller 7 is rotatably held in the pocket 6.

  FIG. 6 shows a rolling bearing 21, which is an assembly of the cage 1 and the required number of rollers 7, specifically a needle roller bearing.

  Note that reference numeral 8 in FIGS. 5A and 6 indicates a trace of post-processing by turning or grinding performed to erase a scratch generated when the pocket 6 is punched.

  FIG. 7 shows a punching device embodying a conventional processing method of the cage 1. In this punching device, a fixed cylindrical body 9 is fixed in a cantilever state, and a base portion 10 b of a cylindrical die 10 fixed in a cantilever state is inserted and supported inside the fixed cylindrical body 9.

  A processing portion 10a extends from the base portion 10b of the die 10 in the distal direction. As shown in FIG. 7C, the processed portion 10a of the die 10 has a cylindrical shape whose center is displaced in the direction of the punch 20 (vertically upward) with respect to the base portion 10b. However, it is not a perfect cylinder, and the zenith is rounded to stabilize punching.

  The processed portion 10a has a smaller diameter than the base 10b, but the height of the top coincides with the height of the top of the base 10b. The base portion 10b and the processed portion 10a are provided with a through hole 11 centered on the center of the base portion 10b, and the waste is discharged through the through hole 11.

  A workpiece 14 is detachably fitted to the processed portion 10a. As shown in FIG. 7 (b), the workpiece 14 is in a semi-finished product state before the pocket 6 of the cage 1 is molded, and has an inward flange edge formed at the body portion 2 and both ends thereof. It consists of four. The waist portion 2 is formed with a constricted portion 3 at an intermediate portion in the axial direction, and a shoulder portion 5 is formed between the constricted portion 3 and the collar edge 4.

In the processed portion 10 a, radial positioning ribs 15 are provided at two axial positions on the outer diameter surface of the die 10. These positioning ribs 15 are formed in a square cross section having a shape matching a square space surrounded by the shoulder portions 5 on both sides of the workpiece 14 and the flange edges 4 and the constricted portions 3 on both sides of each shoulder portion 5. ing. An axially long punch hole 16 is provided in a range extending between the axially intermediate portions of the positioning ribs 15 on both sides. The punch hole 16 penetrates the through hole 11 from the outer diameter surface.

  The eccentric amount of the processing portion 10a is formed larger than the height of the positioning rib 15. When the workpiece 14 fitted to the positioning rib 15 is lifted in the radial direction and taken out in the axial direction, and the workpiece 14 is set in the processing portion 10a. Gives a margin in the radial direction.

  In a state where the workpiece 14 is set in the processing portion 10a, a cylindrical holding jig 18 is fitted from the tip of the processing portion 10a and pressed against one end surface (the brim edge 4) of the workpiece 14. A punch 20 facing the punch hole 16 is installed above the processing portion 10a so as to be movable up and down.

  When punching the pocket 6, the work 14 is intermittently rotated in the circumferential direction integrally with the pressing jig 18, and the punch 20 is driven in synchronization with the work 14, whereby the pocket 6 is formed by so-called outer punching.

  According to the above processing method, scratches due to the pressing of the pressing jig 18 remain on the brim edge 4 of the finished cage 1. If such scratches remain, the mating member that comes into contact with the bearings is worn when the bearing is used, and the scratches cause damage to the cage 1 and a reduction in the service life. In order to eliminate these problems, it is necessary to perform post-processing such as turning and grinding to eliminate the scratches, which increases the processing cost.

  In the prior art, since the scratches generated during the punching of the pocket 6 are erased by post-processing, the post-processing traces 8 (FIG. 5A, FIG. 5) are formed on the outer surface of the collar 4 of the cage 1 as a product. 6) remains as one feature.

On the other hand, in order to avoid the occurrence of scratches as described above, the pocket punching method shown in FIG. 8 is known (Patent Document 1). In this punching method, the outer diameter surface of the work 23 of the cage is housed in a die 24, the inner diameter surface of the shoulder portion 25 at one end of the work 23 is held by the chuck 26, and the punch 27 inserted into the inner diameter side of the work 23 is inserted. The pockets are formed by pressurizing with.

Japanese Patent No. 3735160 (paragraph 0003, FIG. 4)

  In the prior art shown in FIG. 8, the inner diameter surface of one shoulder portion 25 of the work 23 is gripped by the chuck 26, the die 24 is disposed on the outer diameter surface of the work 23, and the punch 27 is disposed inside the work 23. This is a so-called hollow die arranged in

  In the case of the internal punch type, the stroke of the punch 27 is limited by the diameter of the work 23, so that it is limited to a cage having a large diameter (for example, an inner diameter of about 20φ or more), and corresponds to the case of a cage having a small diameter. There is a problem that cannot be done.

  Further, although the shoulder portion 25 of the work 23 is gripped by the chuck 26, since the end portion of the pocket formed by the punch 27 reaches the shoulder portion 25, the gripping margin of the chuck 26 becomes small and stable. There is a problem that it cannot be gripped. In addition, if a slight grip allowance portion is gripped with a strong force, a scratch is generated on the outer surface of the shoulder portion 25, and there is a problem that post-processing is required to erase the scratch.

  Accordingly, an object of the present invention is to provide a rolling bearing cage that solves these problems, a rolling bearing using the cage, and a method for processing the cage.

In order to solve the above-described problems, a rolling bearing cage according to the present invention is a rolling bearing cage in which a required number of pockets are formed by punching at a constant interval in the circumferential direction of a body portion of a cylindrical workpiece. The end face of the product after the punching process is maintained in an unprocessed state as the workpiece before the punching process (hereinafter referred to as a first invention).

  Specifically, when punching the pocket, the work and the jig are pressed by pressing the holding jig for intermittently rotating the work in the inner diameter direction while making a surface contact with the range extending between both the shoulders. Therefore, it is possible to realize a configuration in which the outer surface of the workpiece is maintained in an unprocessed state as the workpiece.

  In order to solve the above-mentioned problem, a rolling bearing according to the present invention is a rolling bearing including a cage and rolling elements held by the cage, and the cage according to the first invention is used as the cage. (Hereinafter referred to as the second invention).

  Furthermore, in order to solve the above-described problem, a method of manufacturing a cage according to the present invention sets a workpiece of the cage around a die processing portion and uses a holding jig integrated with the workpiece. In the processing method of the cage in which the intermittent rotation is given to the workpiece and the pocket is punched from the outer diameter side of the workpiece in synchronization with the intermittent rotation, the holding jig includes the cylindrical portion and one end portion of the cylindrical portion. And a predetermined number of pressing claws formed at predetermined intervals in the circumferential direction. The pressing claws are arranged along the outer diameter surface of the workpiece, and the inner diameter formed by the entire pressing claws is reduced. By doing so, these holding claws and the workpiece are integrated (referred to as a third invention).

  As described above, according to the first invention to the third invention, post-processing for eliminating the generation of scratches associated with the punching of the cage is not necessary, so that the manufacturing cost of the cage and the rolling bearing can be reduced. be able to. In the case of the third invention, since it is a so-called outer punch, it is not affected by the size of the cage, and a pocket punching process can be performed on a cage of any size. Furthermore, since the processing apparatus for carrying out the third invention has many configurations in common with those of the conventional processing apparatus, new equipment and technology introduction are not required.

Fig.1 (a) is a perspective view of the holder | retainer of Embodiment 1, FIG.1 (b) is sectional drawing same as the above, FIG.1 (c) is sectional drawing which shows the example of another holder | retainer. FIG. 2 is a perspective view of the above rolling bearing. 3A is a partial cross-sectional view of the processing apparatus according to the second embodiment, FIG. 3B is an enlarged cross-sectional view of the workpiece, and FIG. 3C is a cross-sectional view taken along line X1-X1 in FIG. It is. 4A is a partial perspective view of the same, and FIG. 4B is a perspective view of the holding jig of the same. Fig.5 (a) is a perspective view of the holder | retainer of a prior art example, FIG.5 (b) is sectional drawing same as the above. FIG. 6 is a perspective view of a conventional rolling bearing. 7A is a partial cross-sectional view of a conventional processing apparatus, FIG. 7B is an enlarged cross-sectional view of a workpiece, and FIG. 7C is a cross-sectional view taken along line X2-X2 in FIG. It is. FIG. 8 is a partial cross-sectional view of another conventional example.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
[Embodiment 1]

  The cage 1 and the rolling bearing 21 using the cage 1 according to the first embodiment shown in FIGS. 1 (a), 1 (b), and 2 have been described based on FIGS. 5 (a), 5 (b), and 6. The structure is basically the same as that of the prior art. The difference is as follows.

  That is, the cage 1 according to the above-described prior art is generically referred to as the outer peripheral surface of the trunk portion 2 including the collar 4 (that is, the end surface of the cage 1) and the shoulder 5 (hereinafter referred to as the outer surface of the cage 1). In FIG. 5 (a), FIG. 6), there is a trace 8 of post-processing by turning or grinding to erase scratches generated during processing. However, in the cage 1 according to Embodiment 1 of the present invention, There is no such scratch on the outer surface of the cage 1, and therefore there is no scratch and an unprocessed state of the workpiece, and there is no post-processing trace 8.

  As described above, in order to maintain the outer surface of the cage 1 in an unprocessed state as a workpiece before punching, in the case of this embodiment 1, the shoulders 5 on both sides are punched when the pocket 6 is punched. The work and the holding jig are integrated by bringing the holding jig into surface contact over a wide range and exerting a tightening force. By performing punching of the pocket 6 in the tightened state, the finish as described above, that is, the finish in which the outer surface of the collar 4 or the shoulder 5 is maintained in the unprocessed state as the workpiece before punching is performed. Realized.

  The retainer 1 that is an object of the present invention is not limited to the one having the inward flange edges 4 provided at both ends as described above, and has no collar edge 4 as shown in FIG. A pocket 6 is formed in the shallow constricted portion 3a of the body-like body portion, and shoulder portions 5a are formed on both sides of the pocket 6, and others having an outward flange edge are omitted in the drawing.

The other configuration of the cage 1 according to the first embodiment and the rolling bearing 21 using the cage 1 is exactly the same as that according to the prior art shown in FIG. 5 and FIG. The same code | symbol is attached | subjected and the description uses all the description of the cage | basket 1 which concerns on the above-mentioned prior art, and the rolling bearing 21 using this.
[Embodiment 2]

  Next, a processing method of the cage will be described as a second embodiment with reference to FIGS. 3 and 4. In the punching device in this case, the fixed cylindrical body 30 is fixed in a cantilever state, and a base portion 31 b of a cylindrical die 31 fixed in a cantilever state is inserted and supported inside the fixed cylindrical body 30.

  A processing portion 31a extends from the base portion 31b of the die 31 in the distal direction. The processed portion 31a of the die 31 has a cylindrical shape whose center is displaced in the direction of the punch 45 (vertically upward) with respect to the base portion 31b, as shown in FIG. However, it is not a perfect cylinder, and the zenith is rounded to stabilize punching.

  The processed portion 31a has a smaller diameter than the base portion 31b, but the height of the top portion matches the height of the top portion of the base portion 31b. The base portion 31b and the processing portion 31a are provided with a through hole 32 centered on the center of the base portion 31b, and the waste is discharged through the through hole 32.

  A workpiece 35 is detachably fitted to the processing portion 31a. As shown in FIG. 3 (b), the workpiece 35 is in a semi-finished product state before the pocket 6 of the cage 1 is formed, and has an inward flange edge formed on the body portion 2 and both ends thereof. It consists of four. The waist portion 2 is formed with a constricted portion 3 at an intermediate portion in the axial direction, and a shoulder portion 5 is formed between the constricted portion 3 and the collar edge 4.

  In the processed portion 31 a, circumferential positioning ribs 34 are provided at two axial positions on the outer diameter surface of the die 31. These positioning ribs 34 are formed in a square cross section having a shape that matches a square space surrounded by the shoulders 5 on both sides of the workpiece 35 and the flange edges 4 and the constricted parts 3 on both sides of each shoulder 5. ing. Punch holes 37 that are long in the axial direction are provided in a range extending between the axially intermediate portions of the positioning ribs 34 on both sides. The punch hole 37 penetrates the through hole 32 from the outer diameter surface.

  The eccentric amount of the processing portion 31a is formed larger than the height of the positioning rib 34, the workpiece 35 fitted to the positioning rib 34 is lifted in the radial direction, the periphery of the die 31 is taken out in the axial direction, and vice versa. A margin in the radial direction when the workpiece 35 is set on the machining portion 31a from the outside of the workpiece 31 is given.

  In the state where the workpiece 35 is set in the processing portion 31 a as described above, the holding jig 39 is fitted from the tip end side of the processing portion 31 a and pressed against the outer diameter surface of the workpiece 35.

  As shown in FIGS. 4 (a) and 4 (b), the holding jig 39 has a predetermined number of holding claws 42 arranged in a comb-teeth with a constant width 41 in the circumferential direction over the entire circumference of one end of the cylindrical portion 40. It is provided in a shape. The pressing claws 42 are formed in an elongated plate shape having elasticity in the radial direction, and the number thereof (= the number of intervals 41 between the pressing claws 42) is equal to the number of pockets 6 (see FIG. 1) to be processed into the work 35. Equally, the interval 41 is formed slightly larger than the width of the punch 45 in order to avoid interference with the punch 45.

  The length of the presser pawl 42 is two to three times longer than the work 35, and the inner diameter of the cylindrical surface formed by the inner surface of each presser pawl 42 matches the outer diameter of the work 35. The inner surface shape is formed into an arc surface that comes into surface contact with the outer diameter surface of the work 35.

  Furthermore, the outer surface of the tip end portion of each presser claw 42 is a tapered surface 43 inclined toward the inner diameter side. The outer diameter formed by the entirety of each presser claw 42 is formed to be slightly larger than the inner diameter of the fixed cylindrical body 30, and when the tip is pushed into the fixed cylindrical body 30 while being guided by the tapered surface 43, The entire pressing claws 42 are reduced in diameter toward the inner diameter side, are in surface contact with both shoulder portions 5 of the work 35, and exert a tightening force on the shoulder portions 5.

  The cylindrical portion 40 is formed to have a larger diameter than the die holder 33, and a connection hole 44 for a driving portion (not shown) is provided in a part thereof. The drive unit advances and retracts the holding jig 39 in the axial direction at the beginning and end of the punching process, enables the workpiece 35 to be attached and detached, and is intermittently fed in the circumferential direction at the size of the interval 41 during the punching process.

  The punching device is used to punch the pocket 6 into the workpiece 35. The die holder 33 and the holding jig 39 in FIG. 3 are retracted, the workpiece 35 is inserted from the open end of the die 31, and a predetermined position of the machining portion 31a is obtained. Set to. The workpiece 35 is stabilized by fitting both the shoulder portions 5 to the positioning ribs 34.

  Next, the die holder 33 and the holding jig 39 are advanced, and the free end portion of the die 31 is supported by inserting the tip portion of the die holder 33 into the inner hole of the tip portion of the die 31 closely. In addition, by closely inserting the tip end of the presser claw 42 of the presser jig 39 into the inner hole of the tip end portion of the fixed cylindrical body 30, the inner diameter surface of the presser claw 42 is entirely reduced in diameter, Tighten shoulder 5 of

  When the pressing jig 39 is intermittently driven in the circumferential direction by the drive unit, the pressing jig 39 and the workpiece 35 are intermittently fed integrally by friction of the pressing claw 42. In accordance with the intermittent feed timing, the punch 45 provided above the processing portion 31a is lowered to the portion of the space 41 between the pressing claws 42, and the pocket 6 is formed in the workpiece 35 by punching. By repeating such processing, when the pocket 6 is formed over the entire circumference of the work 35, the die holder 33 and the holding jig 39 are retracted, and the work 35 is removed from the die 31.

  The workpiece 35 is intermittently fed integrally with the holding jig 39 because the friction between all the pressing claws 42 of the holding jig 39 and the outer diameter surface of the shoulder portion 5 of the workpiece 35 is caused by the workpiece 35 and the processed portion. It is because it is larger than the friction between 31a.

  As described above, the retainer 1 (see FIG. 1) manufactured by the processing method of the second embodiment has the pressing jig 39 against the collar 4 (end surface of the retainer 1) when the pocket 6 is punched. Since there is no contact, there will be no scratches caused by the contact. Therefore, there is no need for post-processing for erasing the flaw, so that the collar 4 is maintained in an unprocessed state as the workpiece 35. The surface roughness data is shown in Table 1 in comparison with the above-described conventional example. It can be seen that there is a significant difference compared to the case of the conventional example.

  Since the pressing claw 42 of the pressing jig 39 is in surface contact with the outer peripheral surface of the trunk portion 2 including the shoulder portion 5, there is no risk of scratching these portions, but the outer peripheral surface of the trunk portion 2 There is some effect on roughness. However, it is a very small numerical value with respect to the standard value, and is not a numerical value that requires post-processing (see Table 1).

Further, the roundness of the outer diameter is similar to that of the conventional example, and even if the work 35 is gripped from the outer diameter surface by the holding jig 39, there is no substantial influence on the roundness. it can.

  3A showing the processing apparatus according to the second embodiment of the present invention and FIG. 7A showing the conventional processing apparatus, it is clear that a die is started in both apparatuses. The components and arrangement of the device are not changed. The only difference is that in the case of the second embodiment, the inner diameter of the fixed cylindrical body 30 is larger than that of the conventional example, and a comb-like pressing claw 42 is provided in place of the pressing jig 39. Therefore, it is only necessary to make some changes to the conventional apparatus, and it is not necessary to introduce new equipment or technology, so that the processing cost can be reduced.

DESCRIPTION OF SYMBOLS 1 Cage 2 Body part 3, 3a Constriction part 4 Collar edge 5, 5a Shoulder part 6 Pocket 7 Roller 8 Trace of post-processing 9 Fixed cylindrical body 10 Die 10a Processing part 10b Base 11 Through-hole 14 Work 15 Positioning rib 16 Punch hole DESCRIPTION OF SYMBOLS 18 Pressing jig 20 Punch 21 Rolling bearing 23 Work 24 Die 25 Shoulder part 26 Chuck 27 Punch 30 Fixed cylindrical body 31 Die 31a Processing part 31b Base part 32 Through-hole 34 Positioning rib 35 Work 37 Punch hole 39 Holding jig 40 Cylindrical part 41 Interval 42 Pressing claw 43 Tapered surface 44 Connection hole 45 Punch

Claims (6)

  Set the work of the cage around the processing part of the die, give intermittent rotation to the work via a holding jig integrated with the work, and match the intermittent rotation and timing from the outer diameter side of the work In the processing method of the cage that punches out the pocket, the pressing jig is composed of a cylindrical portion and a required number of pressing claws formed at a predetermined interval in the circumferential direction at one end portion of the cylindrical portion, The presser claws and the work are integrated by reducing the inner diameter surface of the presser claws formed by the entire presser claws along the outer diameter surfaces of the work pieces. A processing method of a cage characterized by the above. The method of processing a cage according to claim 1 , wherein the number of pressing claws matches the number of pockets processed in the workpiece. A fixed cylindrical body that is concentric with the die and has a diameter larger than that of the die is provided on one side of the processed portion of the die, and the pressing jig is installed so as to be movable forward and backward in the axial direction. The presser claw is inserted into the inner diameter surface of the fixed cylindrical body over the workpiece set in the processing portion, so that the inner diameter surface of the presser claw formed by each presser claw is reduced in diameter. The method for processing a cage according to claim 1 or 2 , wherein each pressing claw exerts a tightening force on a workpiece set in a section. The method of processing a cage according to claim 3 , wherein a taper surface is formed on the outer surface of the tip of the presser claw, and the taper surface serves as a guide for insertion into the inner diameter surface of the fixed cylindrical body. . The method for processing a cage according to any one of claims 1 to 4 , wherein a positioning rib is formed in the processed portion of the die so that the shoulder inner diameter portion of the workpiece is fitted. Processed portion of the die is formed in a cylindrical shape that is eccentric in the direction of the punch relative to the base of the die, any of claims 1 to 5 in which the eccentricity is characterized in that it is set larger than the height of the positioning ribs A method for processing the cage according to claim 1.

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