JP2007170586A - Manufacturing method for bearing ring for rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a bearing ring for a rolling bearing having excellent dimensional precision inexpensively. <P>SOLUTION: In this manufacturing method, plastic working is applied to a single raw material 28 to form an intermediate raw material 43 whose part close to the outside diameter is proper for manufacturing an outer ring for the rolling bearing and whose part close to the inside diameter is proper for manufacturing an inner ring for the rolling bearing. Then, the intermediate raw material 43 is separated in an intermediate part in the radial direction to form a raw material 30 for the outer ring for manufacturing the outer ring for the rolling bearing and a raw material 31 for the inner ring for manufacturing the inner ring for the rolling bearing. The working for forming the part close to the inside diameter into a shape being proper for manufacturing the inner ring for the rolling bearing includes burring. The working for forming the part close to outside diameter into a shape being proper for manufacturing the outer ring for the rolling bearing includes drawing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an improvement in a method for producing an inner ring and an outer ring constituting various rolling bearings such as a single-row radial tapered roller bearing at a low cost.

  Rolling bearings are incorporated in the rotating support parts of various industrial machines and machinery, but in order to form rotating support parts to which large radial loads and axial loads are applied, tapered roller bearings using tapered rollers as rolling elements are used. used. FIG. 5 shows one described in Patent Document 1 as an example of such a tapered roller bearing. This tapered roller bearing 1 includes an outer ring 3 having a conical concave outer ring raceway 2 on an inner peripheral surface, an inner ring 5 having a tapered convex inner ring raceway 4 on an outer peripheral surface, and the outer ring raceway 2 and the inner ring raceway 4. It is composed of a plurality of tapered rollers 6, 6 provided so as to be freely rollable therebetween. Each of these tapered rollers 6 and 6 has an outer peripheral surface as a tapered convex rolling surface 7 that contacts the outer ring raceway 2 and the inner ring raceway 4. In addition, among the both ends of the outer peripheral surface of the inner ring 5, a large-diameter side collar 8 is formed at the large-diameter side end, and a small-diameter side collar 9 is formed at the small-diameter side end. The small diameter side flange 9 may be omitted. The tapered roller bearing 1 configured in this manner allows the relative rotation of the inner and outer rings 5 and 3 while supporting a radial load and an axial load. For this reason, each of the tapered rollers 6 and 6 has the outer ring raceway 2 and the inner ring raceway in a state where the head 10 which is the end face on the large diameter side and the inner side surface 11 of the large diameter side flange 8 are in contact with each other. Revolve between 4 and rotating.

  The outer ring 3 and the inner ring 5 constituting the tapered roller bearing 1 as described above are formed by sequentially performing necessary processes such as forging, cutting, and grinding on a material made of an iron alloy such as bearing steel. Yes. Further, the outer ring 3 and the inner ring 5 can be efficiently manufactured with good material yield, and the outer ring 3 and the inner ring 5 can be manufactured from the outer side in the radial direction of a single material in order to reduce the manufacturing cost of the outer ring 3 and the inner ring 5. Similarly, methods for manufacturing inner rings from the inside are also conventionally known, for example, as described in Patent Documents 2 to 4.

  Of these, Patent Document 2 describes a method of manufacturing a bearing ring for a rolling bearing that is suitable for producing an outer ring and an inner ring for a single row deep groove type ball bearing. In the case of the first example of the conventional method, first, the outer portion near the outer diameter is appropriate for making a rolling bearing outer ring by plastic deformation of a single material, and the inner portion near the inner diameter is also suitable for the inner ring for rolling bearing. The intermediate material that is appropriate for making Thereafter, the intermediate material is separated at the intermediate portion in the radial direction and the center portion is punched out to obtain an outer ring material for producing the outer ring for rolling bearing and an inner ring material for producing the inner ring for rolling bearing. Thereafter, the outer ring material and the inner ring material are separately subjected to plastic working to form an inner ring and an outer ring, respectively.

In addition, in the case of the manufacturing method described in Patent Document 3, a portion closer to the outer diameter rolls by further forging a disk-shaped intermediate material made by forging a cylindrical material. A second intermediate material is made that is suitable for making the outer ring for bearings, and that is also suitable for making the inner ring for rolling bearings in the portion closer to the inner diameter. Thereafter, the second intermediate material is separated at the intermediate portion in the radial direction, and the center portion is punched out to obtain an outer ring material for making an outer ring for a rolling bearing and an inner ring material for making an inner ring for a rolling bearing.
Furthermore, in the case of the manufacturing method described in Patent Document 4, a stepped cylinder in which a wire rod or a rod is subjected to plastic working and the center portion is punched out so that the large diameter portion and the small diameter portion are continuous at the step portion. Create an intermediate material. Then, this intermediate material is cut at a step in the middle in the radial direction, the outer ring portion is used as an outer ring material for making an outer ring for rolling bearings, and the inner ring portion is used for making an inner ring for rolling bearings. And
In short, in any of the manufacturing methods described in Patent Documents 2 to 4, when the material is subjected to plastic working to be an intermediate material, the material is pressed in the axial direction to cause the metal material to flow. And in order to make the outer ring | wheel for rolling bearings in the outer diameter part of this intermediate material, and making the inner ring | wheel for rolling bearings similarly in the inner diameter part, it is set as an appropriate shape, respectively.

  In the case of the conventional method for manufacturing a bearing ring for rolling bearings as described in Patent Documents 2 to 4 described above, a large force is required in the process of plastic processing the material into an intermediate material, an outer ring material, and an inner ring material. become. For this reason, in order to prevent an increase in the size of the equipment (an increase in the capacity of the press device), as described in Patent Document 3, it is common to perform the plastic working (forging) hot. However, in the plastic working by hot, it is necessary to consider the thermal expansion difference between the mold and the workpiece (material, intermediate material, etc.), and thus the dimensional accuracy cannot be sufficiently high. Moreover, the hot-worked workpiece has a decarburized layer on the surface. In addition, as a result of including this decarburized layer in the part to be removed by the cutting process in the subsequent process, the part to be removed increases, not only the yield of the material is deteriorated, but also the processing time is prolonged and the productivity is deteriorated. To do. These increase the manufacturing cost of the rolling bearing race.

  The problems as described above can be solved by performing the plastic working cold. However, if the conventional methods described in Patent Documents 2 to 4 are carried out as they are, it is inevitable that the equipment will be enlarged (the capacity of the press device will increase). That is, the plastic working (forging) by cold increases the deformation resistance of the material (metal material) compared to the plastic working by hot (depending on conditions, it is about four times hot during cold). Therefore, the load required for processing (= deformation resistance × processing area) increases.

  Such an increase in the load required when performing plastic working by cold is a problem regardless of the shape and size of the rolling bearing raceway to be produced. This is particularly noticeable when a small (thin-walled) rolling bearing raceway ring is manufactured while ensuring the material yield. In other words, the conventional methods described in Patent Documents 2 to 4 will be implemented while considering that an inner ring and an outer ring, at least one of which is thin, are made of a single material and that the portion discarded as scrap is reduced. In this case, in order to plastically process the material to make it an intermediate material, the load required to flow the metal material by pressing the material in the axial direction becomes considerably large (the above problem becomes remarkable). Of course, such a problem becomes more prominent as the size of the rolling bearing race to be manufactured increases. For example, a raceway of at least one of an outer ring and an inner ring constituting a large tapered roller bearing incorporated in a portion that supports a large radial load and thrust load, such as a rotation support portion of an industrial machine such as a rolling mill or a printing press. The above problem becomes most noticeable when the ring is thinned.

JP 2004-108429 A Japanese Patent Laid-Open No. 5-277615 Japanese Patent Laid-Open No. 11-244983 JP 2000-71046 A

  In view of the above-described circumstances, the present invention has been invented in order to realize a manufacturing method capable of obtaining a rolling bearing bearing ring with good dimensional accuracy at a low cost.

  Each of the present invention is a method for manufacturing a bearing ring for a rolling bearing, in which an outer ring for rolling bearing and an inner ring for rolling bearing, each having an annular shape and different diameters, are made from a single plate-shaped material. For this purpose, this material is subjected to plastic working so that the outer diameter portion is appropriate for making the outer ring for rolling bearings, and the inner diameter portion is also appropriate for making the inner ring for rolling bearings. The material. Thereafter, the intermediate material is separated at the intermediate portion in the radial direction to obtain an outer ring material for making the rolling bearing outer ring and an inner ring material for making the rolling bearing inner ring.

In particular, in the method for manufacturing a bearing ring for rolling bearings according to claim 1 of the present invention, the processing of making the portion closer to the inner diameter of the intermediate material into an appropriate shape for producing the inner ring for rolling bearings. , Burring (Punches with a larger outer diameter than the inner diameter of the lower hole are pushed into the material in which the lower hole is previously formed, and the peripheral portion of the lower hole is perpendicular to the material while expanding the inner diameter of the lower hole. And plastic working to form a cylindrical portion at the periphery of the expanded hole. This burring process is performed cold.
When the invention described in claim 1 is carried out, for example, as described in claim 2, the outer diameter portion of the intermediate material is formed into an appropriate shape for producing an outer ring for a rolling bearing. Drawing can be included in the processing. This drawing process is performed cold.

Further, in the method for manufacturing a bearing ring for a rolling bearing according to claim 3, a drawing process (in which a portion close to the outer diameter of the intermediate material is formed into an appropriate shape for producing the outer ring for a rolling bearing) And the diameter of the plate-like portion or the conical portion is reduced to make this portion a cylindrical shape). This drawing process is performed cold.
When the invention described in claim 3 is carried out, for example, as described in claim 4, the inner ring material is formed into a ring shape, and the inner ring material is subjected to burring on the inner diameter portion and at the same time the outer diameter portion. This inner ring material can also be processed into a cylindrical second inner ring material by applying a reversal process to narrow down the portion.
Alternatively, when carrying out the invention described in claim 3 as described above, for example, as described in claim 5, the portion closer to the inner diameter of the intermediate material may be a cylindrical portion made by extrusion. it can.

Further, in any of the above-described inventions, as described in, for example, claim 6, a cylindrical shape obtained by cutting a material into a predetermined length of a bar or wire having a predetermined outer diameter. Can be made by upsetting, expanding the diameter while compressing the spare material in the axial direction.
Alternatively, as described in claim 7, at least a part of the outer ring material can be expanded in diameter to form an outer ring.

  According to the method for manufacturing a bearing ring for rolling bearings of the present invention as described above, a bearing ring for rolling bearings having good dimensional and shape accuracy can be obtained at low cost. The reason for this is that an appropriate shape for producing an inner ring for a rolling bearing by machining including burring (in the case of the invention described in claim 1), and an appropriate shape for producing an outer ring for rolling bearing by machining including drawing. This is because, in order to obtain the respective shapes (in the case of the invention described in claim 3), it is possible to cold-work the rolling bearing race. In short, the method of manufacturing the bearing ring for rolling bearing according to the present invention is performed by burring processing or drawing processing that can keep the load for processing low compared to forging processing, so even without using a particularly large press device, The rolling bearing race can be made by cold working that facilitates ensuring the size and shape accuracy.

  In particular, in the case of the present invention, the burring or drawing is performed before the intermediate material is separated at the intermediate portion in the radial direction into the outer ring material and the inner ring material. The outer ring material or the inner ring material can be processed effectively. This point will be described below.

  First, in a state where plastic processing is performed on the material, and burring processing is performed to make the shape of the inner diameter portion suitable for making the inner ring for the rolling bearing, the outer ring for rolling bearing is provided on the outer diameter portion of the material. The part for manufacturing exists (integrally) in a state of being continuous to the radially outer side of the part closer to the inner diameter to be subjected to burring. Therefore, in the portion near the outer diameter of the material, there is a portion having sufficiently large strength and rigidity in the radial direction and not easily deformed by the radial force. For this reason, when the portion closer to the inner diameter is bent into a cylindrical shape by the burring process, the material is hardly deformed in a direction in which the diameter is reduced. For this reason, the portion near the inner diameter is bent accurately around the desired radial position by the burring process, so that a cylindrical shape having a desired diameter and shape, that is, an appropriate shape and Can be processed into dimensions.

  On the other hand, when the material is subjected to plastic working and the drawing is performed to make the shape of the portion near the outer diameter appropriate for making the outer ring for the rolling bearing, the inner ring for the rolling bearing is provided on the portion closer to the inner diameter of the material. The part for manufacturing exists (integrally) in a state of being continuous on the radially inner side of the portion near the outer diameter to be subjected to the drawing process. When plastically deforming the portion close to the outer diameter of the plate-like material in this drawing process while reducing the diameter into a cylindrical shape, the metal material is pulled to some extent in the portion processed into the cylindrical shape, This metal material is supplied from a portion closer to the inner diameter of the material. Even when the drawing is performed, in order to ensure the shape and dimensional accuracy after the drawing, it is necessary that the rigidity of the portion serving as a reference for the drawing is sufficiently ensured. Ensuring such rigidity can be sufficiently achieved because the material exists in a portion closer to the inner diameter than a portion serving as a reference for the drawing process.

  In burring and drawing, a part of the metal material is stretched in the circumferential direction (in the case of burring) and contracted (in the case of drawing). The thickness dimension of the material changes from the thickness dimension of the material. In addition, since the amount of stretching or shrinking varies depending on the radial position of the material, the amount of change in the thickness dimension varies depending on the radial position. For example, a portion subjected to burring processing becomes thinner than the original thickness, and the degree of thinning toward the tip becomes significant. On the other hand, the portion subjected to the drawing process becomes thicker than the original thickness, and the thickness becomes uneven. For this reason, even if a plate material having a constant thickness dimension is directly subjected to the burring process or the drawing process to produce an intermediate material, it is difficult to set the thickness dimension of each part of the intermediate material to a desired value. Therefore, when an intermediate material is produced by subjecting a plate material having a constant thickness dimension to the burring or drawing process as described above, in order to make the distribution of the thickness dimension necessary, Extra processing such as handling is required again. Such extra processing is not preferable because it causes an increase in manufacturing cost.

  On the other hand, as described in claim 6, if the material is made by upsetting to expand the diameter while compressing the cylindrical (solid) preliminary material in the axial direction, the thickness of the material in the radial direction is increased. Can be easily regulated as desired. The thickness distribution of each part of the intermediate material obtained by subjecting this material to burring or drawing can also be adjusted to a desired thickness distribution. Note that the process of processing the preliminary material into the material by upsetting is not limited to cold, and can be performed warm to reduce the load required for processing. In particular, when the workpiece is large and the load required for the upsetting process is very large, this upsetting process can be performed warmer than cold in order to reduce the processing load. Is preferred. That is, the processing from the preliminary material to the material does not require dimensional accuracy and shape accuracy as much as the processing from this material to the intermediate material. You may do it. However, it is not preferable to perform hot processing that causes a decarburized layer on the surface.

  In addition, as described in claim 5, if the portion closer to the inner diameter of the intermediate material, which should be used as the inner ring material, is a cylindrical portion made by extrusion, the width dimension (axial dimension) compared to the diameter. Can build a large inner ring. That is, in the case of burring, since the periphery of the pilot hole is processed into a cylindrical shape, it is difficult to process the inner ring having a large width dimension relative to the diameter. On the other hand, according to the extrusion process, the inner ring having a larger width dimension than that of the diameter can be formed because it is less likely to be limited by the ratio between the diameter and the width dimension than in the case of burring.

[First example of embodiment]
1 to 3 show a first example of an embodiment of the present invention corresponding to claims 1, 2, 3, 6, and 7. FIG. In the case of this example, first, by cutting a long wire having a predetermined outer diameter drawn from an uncoiler (not shown) into a predetermined length, a cylindrical preliminary material as shown in FIG. (Billette) 12 is obtained. Since this cutting operation is performed by shearing with a press in consideration of processing efficiency, the shape of both end surfaces in the axial direction of the preliminary material 12 {the cut surface portion (fracture surface) with broken lines in FIG. 1} is distorted. Yes. Therefore, an end face correction process for pressing the correction die on the both end faces is performed to obtain a second preliminary material 13 as shown in FIG. The shape of the second preliminary material 13 is plastically deformed into a beer barrel shape as it is pressed in the axial direction between a pair of straightening dies.

  The second preliminary material 13 obtained as described above is compressed in the axial direction by the upsetting device 14 as shown in FIG. 2, and the disk-shaped first material 13 as shown in FIG. Three spare materials 15 are assumed. In this way, when the second preliminary material 13 is compressed in the axial direction to form the third preliminary material 15, the axis of the second preliminary material 13 is shown in FIGS. 2A to 2C. The second preliminary material 13 is crushed in the axial direction while restraining both ends in the direction. Then, the second preliminary material 13 is used as the third preliminary material 15 while keeping the diameter of both end portions in the axial direction so as not to expand. The processing apparatus for performing such processing includes a fixed block 16, a die 17, a counter punch 18, a ring punch 19, and a punch 20, as shown in FIG.

  Among these, the fixed block 16 is supported and fixed to a frame or the like of a press working apparatus installed on the floor of the factory. The die 17 is elastically supported above the fixed block 16 by a plurality of elastic members 21, 21 such as compression coil springs. Accordingly, the die 17 is lifted above the fixed block 16 as shown in FIG. 2A in the non-working state, but based on the flow of the metal material during the working. In a state where a large pressure is applied, as shown in FIG. 2C, the elastic member 21 and 21 are lowered until they come into contact with the upper surface of the fixed block 16 against the elasticity of the elastic members 21 and 21. At the center of such a die 17 is provided a lower center hole 22 into which the lower end of the second preliminary material 13 can be fitted. The counter punch 18 is inserted into the lower center hole 22 so as to be movable up and down with respect to the die 17.

  The vertical position of the counter punch 18 is regulated as follows. That is, in the non-working state, as shown in FIG. 2A, the upper end surface of the counter punch 18 is made sufficiently lower than the bottom surface of the processing recess 23 provided on the upper surface of the die 17. . In this state, by inserting the lower end portion of the second preliminary material 13 into the lower center hole 22, the second preliminary material 13 and the central axis of the die 17 can be aligned. Further, when the lower surface of the die 17 is in contact with the upper surface of the fixed block 16 during processing, the upper end surface of the counter punch 18 is slightly below the upper surface of the die 17 (the bottom surface of the processing recess 23). It exists in a recessed position and prevents the fracture surface from flowing radially outward even at the final stage of processing.

  The ring punch 19 is elastically supported concentrically with the die 17 by a plurality of elastic members 21a and 21a such as compression coil springs below a ram 24 of a press machine provided above the die 17. ing. Therefore, the ring punch 19 hangs down below the ram 24 as shown in FIG. 2A in the non-working state. In a state where a large pressure is applied, as shown in FIG. 2C, the elastic members 21a and 21a are resisted against the elasticity of the elastic members 21a and 21a until they contact the lower surface of the ram 24 (with respect to the ram 24). )To rise. Further, the lower end portion of the ring punch 19 can be freely inserted into the processing recess 23 of the die 17 without rattling, and the die 17 and the ring punch 19 are strictly concentric in the inserted state. Like. An upper center hole 25 in which the upper end portion of the second preliminary material 13 can be fitted is provided in the center portion of such a ring punch 19.

  Further, the punch 20 is inserted into the upper center hole 25 so as to be movable up and down with respect to the ring punch 19. In the case of the illustrated example, the punch 20 is fixed to the ram 24, and the punch 20 and the ring punch 19 move up and down relatively as the ring punch 19 moves up and down relative to the ram 24. I have to. The vertical position of the punch 20 is regulated as follows. That is, in the non-working state, as shown in FIG. 2A, the lower end surface of the punch 20 is positioned sufficiently above the lower end surface of the ring punch 19. In this state, by inserting the upper end portion of the second preliminary material 13 into the upper center hole 25, the central axis of the second preliminary material 13 and the central axis of the ring punch 19 can be matched. As shown in FIG. 2C, when the upper end surface of the ring punch 19 is in contact with the lower surface of the ram 24 during processing, the lower end surface of the punch 20 is lower than the lower surface of the ring punch 19. It exists in a position slightly recessed upward, so that the fracture surface does not flow radially outward even at the final stage of processing.

  The second preliminary material 13 as shown in FIG. 1B is crushed in the axial direction by the manufacturing apparatus as shown in FIG. 2, and the third preliminary material 15 as shown in FIG. The following work is performed as follows. First, in a state where the ring punch 19 and the punch 20 are retracted upward together with the ram 24, the lower end portion of the second preliminary material 13 is placed at the upper end portion of the lower center hole 22. And the center axis of the die 17 are matched with each other. Next, the ram 24 is lowered, and as shown in FIG. 2A, the lower end portion of the ring punch 19 is inserted into the processing recess 23 of the die 17, and the upper end portion of the second preliminary material 13 is inserted. Is fitted into the lower end portion of the upper center hole 25. If the ram 24 is further lowered from this state, the second preliminary material 13 is gradually crushed as shown in FIGS. 2 (A) → (B) → (C). A third preliminary material 15 as shown in FIG. With the third preliminary material 15, the fracture surface remains at the thick portion 26 at the center.

  In the case of this example, after the third preliminary material 15 is formed as described above, the axis of the preliminary material 12 is formed at the center of the third preliminary material 15 as shown in FIG. The circular hole 27 is formed by removing the portion corresponding to the both end faces in the direction of the broken surface by piercing, and the annular material 28 is obtained. By this piercing process, the part having the above-mentioned fractured surface together with the scrap 29, the outer ring material 30 {the upper half of FIG. 1 (H)} and the inner ring material 31 {the lower half of FIG. 1 (H)} It is removed from the portion that should become (the portion where the history of the fracture surface remains in the material 28 portion does not remain). The circular hole 27 serves as a pilot hole for burring processing described below.

  The ring-shaped material 28 manufactured as described above is subjected to burring processing in which the inner half of the material 28 is bent on one side in the axial direction over the entire circumference and bent over the entire circumference. . In this burring process, the outer half on the outer diameter side of the material 28 is sandwiched and fixed between a pair of holding dies, and the outer half on the inner diameter side of the material 28 is larger than the inner diameter of the circular hole 27. This is done by pushing a punch having a diameter. As the punch is pushed, the inner diameter of the circular hole 27 is expanded, and the peripheral portion of the circular hole 27 is plastically deformed in a direction perpendicular to the material 28, and a cylindrical portion 32 is formed at the peripheral edge of the expanded hole. It is formed. As a result, as shown in FIG. 1 (E), the first preliminary intermediate material having a substantially L-shaped cross section and an annular shape as a whole, in which the cylindrical portion 32 is continuous from the inner peripheral edge of the annular flange portion 34. 33 is obtained.

  For such a first preliminary intermediate material 33, a sizing device 35 as shown in FIG. 3 is used to make the dimensional accuracy and shape accuracy of the cylindrical portion 32 appropriate as an inner ring material 31 to be described later. Apply sizing. The sizing device 35 includes an outer diameter side and an inner diameter side dies 36 and 37 that are each cylindrical and combined concentrically with each other, and a cylindrical mandrel 38 that can be loosely inserted inside the inner diameter side die 37. A cylindrical ring punch 39 fitted around the mandrel 38 so as to be movable in the axial direction, and a cylindrical counter ring fitted inside the inner diameter die 37 so as to be movable in the axial direction. 40. As described below, such a sizing device 35 performs sizing on the cylindrical portion 32, and at the same time, the flange portion 34 is shaped to be close to an appropriate material for the outer ring material 30 described later. 34 is inclined in the shape of a partially conical cylinder.

  In order to perform such sizing, first, the mandrel 38 and the ring punch 39 are moved away (raised) from the dies 36, 37, and the first preliminary intermediate material 33 is moved to the dies 36, 37. 37 is set on the inner diameter side. That is, the cylindrical portion 32 of the first preliminary intermediate material 33 is fitted into the upper end portion of the inner diameter side die 37, and the flange portion 34 is placed on the upper end surface of the inner diameter side die 37. In this state, the outer peripheral edge of the flange portion 34 is in contact with or close to the inner peripheral surface of the outer diameter side die 36 over the entire periphery. Accordingly, the outer diameter of the flange 34 does not substantially increase further.

  In order to perform sizing from this state, as shown in FIG. 3A, when the mandrel 38 and the ring punch 39 are started to descend, the ring punch 39 crushes the inner diameter side half of the upper surface of the flange portion 34. Meanwhile, the cylindrical portion 32 is pushed into a sizing space 41 surrounded by the outer peripheral surface of the mandrel 38, the inner peripheral surface of the inner diameter side die 37, and the upper end surface of the counter ring 40, and the cylindrical portion 32 is pressed. Sizing At this time, a part of the metal material pressed (flowed) from the inner half of the flange portion 34 by crushing the inner half of the flange portion 34 by the ring punch 39 is the cylindrical portion 32. And the sizing space 41 is filled. At this time, as the mandrel 38 is lowered, the counter ring 40 is lowered to an appropriate position for forming the inner ring material 31 as shown in FIG. Alternatively, the counter ring 40 and the mandrel 38 may be moved to an appropriate position in advance for forming the inner ring material 31 before the ring punch 39 is lowered. In any case, as a result of crushing the inner diameter side half of the upper surface of the flange portion 34 by the lower end surface of the ring punch 39, the shape and dimensions of the cylindrical portion 32 become appropriate as the inner ring material 31. Become.

  The ring punch 39 is further lowered (along with the mandrel 38) from the state in which the inner ring material 31 has been formed in this manner (or while the inner ring material 31 is being formed). When the inner diameter side half is further crushed, the metal material pushed away from the inner diameter side half moves (flows) to the outer diameter side of the flange portion 34. This movement is performed in the thickness direction and the radial direction of the flange portion 34. The lower side in the thickness direction is partitioned by the upper surface of the inner diameter side die 37, and the outer side in the radial direction is the outer diameter. It is partitioned by the inner peripheral surface of the side die 36. Accordingly, the movement of the metal material pushed away from the inner diameter side half is performed in the axial direction (upward) indicated by the arrow A in FIG. 3B and outward in the radial direction indicated by the arrow B. .

  In this case, when considering the moving speed of the metal material in the radial direction of the flange portion 34 between the upper surface and the lower surface of the outer diameter side half of the flange portion 34, the moving speed on the lower surface side is the upper surface side. Faster than the movement speed. This is because the metal material moves not only in the radial direction but also in the axial direction on the upper surface side, whereas it moves only in the radial direction on the lower surface side. For example, the radial direction component of the moving speed of the metal material on both the upper and lower surfaces of the flange portion 34 is seen by the points C and D in FIG. 3B corresponding to the outer peripheral surface of the ring punch 39. In this case, the speed at the point C on the lower surface side becomes faster than the speed at the point D on the upper surface side. As a result, as shown in FIG. 3C, the outer diameter side half of the flange portion 34 is deformed so as to warp upward as it goes to the outer diameter side. Of course, in the deformed state, the outer diameter of the flange portion 34 matches the inner diameter of the outer diameter side die 36. In this state, as shown in FIG. 1 (F) and FIG. 3 (C), the inner half of the flange portion 34 and the cylindrical portion 32 are shaped to match the inner ring material 31. A second preliminary intermediate material 42 is obtained.

  Such a second preliminary intermediate material 42 is taken out from the sizing device 35 and subjected to a drawing process for making an outer diameter portion suitable for rolling a bearing outer ring. This drawing process is performed by reducing the thickness of the second preliminary intermediate material 42 in the radial direction while reducing the diameter of the outer diameter side half. For this purpose, the cylindrical portion of the second preliminary intermediate material 42 and the inner diameter side half of the flange portion 34 are held by a holding die, and the receiving die is connected in series with the holding die, and the outer diameter of the flange portion 34. It arranges in the state located inside the side half. Then, in this state, while handling the outer diameter side surface of the outer diameter side half of the flange portion 34 with the drawing mold, the outer diameter side half portion of the flange portion 34 is pressed against the outer peripheral surface of the receiving mold. As shown in FIG. 1G, it is plastically deformed into a cylindrical shape (partial conical cylindrical shape). As a result, the intermediate material 43 shown in FIG. 1G is obtained. Since the outer diameter side half of the flange portion 34 is inclined in advance in the drawing direction in accordance with the sizing described above, the load (working load) required for drawing as described above is relatively small. I'll do it.

  As described above, when the drawing process for processing the second preliminary intermediate material 42 into the intermediate material 43 is performed, the inner ring material 31 is formed near the inner diameter of the second preliminary intermediate material 42. The power portion is present in a state of being continuous radially inward of the outer diameter side half of the flange portion 34 to be subjected to the drawing. For this reason, at the time of drawing, it is possible to sufficiently secure the rigidity of the inner diameter side half of the flange portion 34, which serves as a reference for drawing, and to ensure the shape and dimensional accuracy after drawing. Further, when the outer diameter side half of the flange portion 34 is plastically deformed into a cylindrical shape while reducing the diameter in accordance with the drawing process, a certain amount of metal material is applied to the portion processed into the cylindrical shape. Although pulled, this metal material is supplied from the inner diameter side half of the flange portion 34. For this reason, the intermediate material 43 in which the inner half portion is the portion to be the inner ring material 31 and the outer half portion is the portion to be the outer ring material 30 can be made with high accuracy.

  If such an intermediate material 43 is made, the intermediate material 43 is separated at the intermediate portion in the radial direction, and the outer ring material 30 and the inner ring material 31 as shown in FIG. To do. The separation method is not particularly limited, but punching with a press is preferable in order to reduce the processing cost. However, in order to improve the properties of the cut surface and facilitate post-processing, cutting with a laser cutter can also be performed. In this way, if the intermediate material 43 is separated into the outer ring material 30 and the inner ring material 31, the inner ring material 31 is used as it is or as a shape correction process such as a rolling process using a roller, Necessary processing and processing such as heat treatment and polishing are performed to complete the inner ring 5 for the tapered roller bearing as shown in FIG.

  On the other hand, the outer ring material 30 expands the diameter of the small diameter side of the partial conical cylindrical shape, and moves the metal material on the small diameter side toward the large diameter side to move in the axial direction. As shown in FIG. 1 (I), the outer peripheral surface is a cylindrical surface and the inner peripheral surface is processed into a bare outer ring 44 having a partially conical concave surface. At this time, the inner ring surface of the outer ring material 30 is handled by a pressing die in a state where the outer ring material 30 is fitted in a holding mold having an inner diameter that matches the outer diameter of the outer ring 44. The obtained outer ring 44 is subjected to sizing for correcting the shape and dimensions of each part as necessary, and is completed as the outer ring 3 shown in FIG.

  Since the manufacturing method of the rolling bearing race of the present example implemented as described above performs each process cold (or warm), the shape accuracy and dimensional accuracy of the material at each stage can be improved. In addition, since there is no decarburized layer on the surface, it is possible to reduce the cutting allowance in the subsequent process, and it is possible to reduce the manufacturing cost by improving the material yield and reducing the time required for cutting. Further, since the load applied to each material in each process is smaller than that in the case of performing cold forging or warm forging, it is possible to prevent the processing equipment from being enlarged and to reduce the cost from this aspect.

  In the case of this example, after the outer ring material 30 is separated from the inner ring material 31, the diameter of the outer ring material 30 and the inner ring material 31 is increased in order to expand the diameter of the outer ring material 30. In order to secure the difference, there is no need to create a scrap. That is, as described in FIG. 8 of the above-mentioned Patent Document 4, in order to ensure a difference in diameter between the outer ring material and the inner ring material, a continuous portion that exists in the radial direction between these two materials. If the continuous portion is disposed as scrap, the yield of the material is deteriorated by the amount of the scrap. On the other hand, in the case of this example, such a portion does not exist, and the metal material to be discarded as scrap can be suppressed to a small amount. Therefore, the cost can be reduced by improving the yield of the material.

In addition, after the outer ring material 30 is separated from the inner ring material 31, the outer ring material 30 may be subjected to reversing molding in which the large diameter side portion is drawn and the small diameter side portion is expanded. If such reverse molding is performed, the minimum inner diameter R _{min of the} outer ring {(J) in FIG. 1} is smaller than the maximum outer diameter D _{max of the} inner ring {(H)} in FIG. 1 (R _min <D _max , It is possible to make a combination from a single material (a part of which is located radially inward of a part of the inner ring). In any case, if the diameter of the outer ring material 30 is increased by press working other than cold rolling, capital investment other than the press working machine becomes unnecessary, and high productivity is always obtained. Roll former is not required. And cost reduction can be achieved by restraining capital investment and improving production efficiency.

[Another example of the embodiment]
The present invention can also be implemented by a process as shown in FIG. FIG. 4 shows five processing methods as second to sixth examples of the embodiment of the present invention, and each will be briefly described below.
[Second Example of Embodiment]
This manufacturing method is performed in the order of (A) → (B) → (C) → (D) → (E) → (F) → (G) → (H) in FIG.
First, the plate-shaped material shown in (A) is subjected to piercing and trimming in (B) to form an annular first preliminary intermediate material, and further subjected to crushing in (C) to obtain the outer diameter side. The second preliminary intermediate material having a wedge-shaped cross section is inclined in a direction in which the thickness dimension decreases as it goes to. Next, burring is performed on the portion near the inner diameter of the second preliminary intermediate material in (D) to form a cylindrical portion on the inner peripheral edge, and then sizing is performed in (E). Next, after drawing the outer half on the outer diameter side in (F), the outer ring material and inner ring material are separated in (G), and the outer ring material is expanded in (H). Diameter and further sizing.

[Third example of embodiment]
This manufacturing method is performed in the order of (I) → (J) → (K) → (L) → (D) → (E) → (F) → (G) → (H) in FIG. Among these, the process of (I) → (J) → (K) → (L) is the same as the process of (A) → (B) → (C) → (D) of the first example of the embodiment described above. The same. Further, the steps after (D) are the same as the second example of the embodiment described above.

[Fourth Example of Embodiment]
This manufacturing method is performed in the order of (I) → (J) → (K) → (M) → (N) → (O) in FIG. Among these, the process of (I) → (J) → (K) is the same as the process of (A) → (B) → (C) in the first example of the embodiment described above. In the case of this example, after making a round bowl-shaped intermediate material by drawing the portion near the outer diameter of the disk-shaped third preliminary material in (M), in (N), The outer diameter portion is separated and the center portion is punched out by piercing to obtain an outer ring material and an inner ring material. Next, in (O), the diameter of the outer ring material is expanded and further sized. Similarly, the inner ring material is processed into a cylindrical second inner ring material by burring the inner diameter portion and reversing the outer diameter portion at the same time.

[Fifth Example of Embodiment]
This manufacturing method is performed in the order of (I) → (J) → (P) → (Q) → (S) → (T) → (U) → (V) → (W) → (X) in FIG. Do. Of these, the process (I) → (J) is the same as the process (A) → (B) in the first example of the embodiment described above, and (U) → (V) → (W) → (X). These steps are the same as the steps (E) → (F) → (G) → (H) in the second example of the embodiment described above. In the case of this example, in (P), a preform for further crushing the cylindrical second preliminary material is applied. Next, in (Q), an upsetting process that crushes in the axial direction is performed to obtain a spare material having a thick central portion and a thin outer diameter portion. Next, in (S), the central portion is crushed and the corresponding metal material is moved to the radial intermediate portion, and a backward extrusion process is performed to form a cylindrical portion in the radial intermediate portion. Next, at (T), a piercing process is performed to punch out the central portion.

[Sixth Example of Embodiment]
This manufacturing method is performed in the order of (I) → (J) → (P) → (R) → (S) → (T) → (U) → (V) → (W) → (X) in FIG. Do. Among these, the process of (I) → (J) → (P) and the process of (T) → (U) → (V) → (W) → (X) are the fifth example of the embodiment described above. It is the same as the case of. In the case of this example, in (R), the central portion of one end face in the axial direction of the preliminary material is crushed and the corresponding metal material is moved to the peripheral portion, and a rear extrusion process is performed to form a cylindrical portion in the peripheral portion. Apply. Then, in the subsequent step (S), an upsetting process is performed in which a portion that is axially removed from the cylindrical portion is expanded radially outward.

  Each example of embodiment mentioned above has shown about the case where this invention is utilized in order to make the outer ring | wheel and inner ring | wheel of a tapered roller bearing. On the other hand, the present invention can also be used to produce an outer ring and an inner ring constituting an angular type ball bearing.

Sectional drawing which shows the 1st example of embodiment of this invention in process order. Sectional drawing which shows an upsetting process in order of a process. Sectional drawing which shows sizing in process order. Sectional drawing which shows another example of embodiment of this invention in order of a process. The partial cutaway perspective view of the tapered roller bearing incorporating the outer ring | wheel and the inner ring | wheel used as the object of the manufacturing method of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tapered roller bearing 2 Outer ring raceway 3 Outer ring 4 Inner ring raceway 5 Inner ring 6 Tapered roller 7 Rolling surface 8 Large diameter side flange 9 Small diameter side flange 10 Head 11 Inner side surface 12 Spare material 13 Second spare material 14 Installation device 15 Third Preliminary Material 16 Fixed Block 17 Die 18 Counter Punch 19 Ring Punch 20 Punch 21, 21a Elastic Member 22 Lower Center Hole 23 Processing Recess 24 Lamb 25 Upper Center Hole 26 Thick Part 27 Circular Hole 28 Material 29 Scrap 30 Outer ring material 31 Inner ring material 32 Cylindrical portion 33 First preliminary intermediate material 34 Flange 35 Sizing device 36 Outer diameter side die 37 Inner diameter side die 38 Mandrel 39 Ring punch 40 Counter ring 41 Sizing space 42 Second preliminary intermediate material 43 Intermediate material 44

Claims (7)

  In order to make the outer ring for rolling bearings and the inner ring for rolling bearings each having an annular shape and different diameters from a single material having a plate shape, this material is subjected to plastic working, and the portion closer to the outer diameter is the rolling bearing. It is appropriate to make the outer ring for use, and the inner diameter part is also appropriate for making the inner ring for the rolling bearing. After making the intermediate material, the intermediate material is separated at the intermediate portion in the radial direction, and the rolling bearing is used. In a method of manufacturing a bearing ring for a rolling bearing that is used as an outer ring material for manufacturing an outer ring and an inner ring material for manufacturing the inner ring for a rolling bearing, a portion closer to the inner diameter of the intermediate material is used for the inner ring for the rolling bearing. A method for manufacturing a bearing ring for a rolling bearing, characterized in that burring is included in the process of forming an appropriate shape for manufacturing.   The method for manufacturing a bearing ring for a rolling bearing according to claim 1, wherein the process of making the portion closer to the outer diameter of the intermediate material into an appropriate shape for producing an outer ring for a rolling bearing includes drawing.   In order to make the outer ring for rolling bearings and the inner ring for rolling bearings each having an annular shape and different diameters from a single material having a plate shape, this material is subjected to plastic working, and the portion closer to the outer diameter is the rolling bearing. It is appropriate to make the outer ring for use, and the inner diameter part is also appropriate for making the inner ring for the rolling bearing. After making the intermediate material, the intermediate material is separated at the intermediate portion in the radial direction, and the rolling bearing is used. In a method of manufacturing a bearing ring for a rolling bearing as an outer ring material for producing an outer ring for a ring and an inner ring material for producing the inner ring for a rolling bearing, a portion closer to the outer diameter of the intermediate material is the outer ring for the rolling bearing. A method for manufacturing a bearing ring for a rolling bearing, characterized in that drawing processing is included in the processing to obtain an appropriate shape for manufacturing the bearing.   The inner ring material is in the shape of a ring, and this inner ring material is processed into a cylindrical second inner ring material by burring the inner diameter portion and reversing the outer diameter portion. A method for manufacturing a bearing ring for a rolling bearing according to claim 3.   The method for manufacturing a bearing ring for a rolling bearing according to claim 3, wherein the inner diameter portion of the intermediate material is a cylindrical portion made by extrusion.   The material is made by upsetting to expand the diameter while compressing a cylindrical preliminary material obtained by cutting a rod or wire having a predetermined outer diameter into a predetermined length in an axial direction. The manufacturing method of the bearing ring for rolling bearings described in any one of them. The manufacturing method of the bearing ring for rolling bearings described in any one of Claims 1-6 which expands at least one part of the raw material for outer rings, and uses it as an outer ring.

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