JP4609259B2 - Roller bearing roller manufacturing method - Google Patents

Description

The present invention is a cylindrical roller bearing, a method of manufacturing a bearing for this filtration time used for spherical roller bearings and tapered roller bearings.

  Conventionally, in order to manufacture a roller bearing roller, for example, a solid material is set between a moving mold and a fixed mold, and the moving mold is moved toward the fixed mold. Compress the solid material in the axial direction while leaving surplus in the gap between the moving side mold and the fixed side mold, and remove the surplus part and finish the outer peripheral surface in the subsequent process. (For example, refer to Patent Document 1 and Patent Document 2).

  4, 5 and 6 show conventional manufacturing methods for cylindrical rollers, spherical rollers and tapered rollers, respectively.

  To manufacture the cylindrical roller, as shown in FIG. 4A, first, a cylindrical solid material 100 having an axial length L6 is set between the moving die 101 and the fixed die 102. . Next, as shown in FIG. 4B, the moving die 101 is moved closer together with the punch 103 toward the fixed die 102. Thereby, the recessed part 104 which has the depth L8 is provided in the both end surfaces of the solid raw material 100, the solid raw material 100 is shape | molded by the axial direction length L7 (L6> L7), and the moving side die | dye 101 and the fixed side die | dye. The surplus meat 105 bulges in the gap D between the two. Then, in the subsequent grinding step, the surplus material 105 is removed and the outer peripheral surface is finished.

  In order to manufacture the spherical roller, as shown in FIG. 5A, first, a cylindrical solid material 110 having an axial length L6 is formed by moving a moving side die 111 having a concave spherical surface and a fixed side. Set with a gap E between the dies 112. Next, as shown in FIG. 5B, the moving die 111 is moved closer together with the punch 113 toward the fixed die 112. Accordingly, the concave portions 114 having the depth L8 are provided on both end faces of the solid material 110, and the solid material 110 is formed to have an axial length L7 (L6> L7), and the moving side die 111 and the fixed side die are formed. In the gap D between 112, the surplus meat 115 bulges. Then, in the subsequent grinding process, the surplus 115 is removed and the outer peripheral surface is finished.

  To manufacture the tapered roller, first, a cylindrical solid material 120 having an axial length L6 is set on a die 121 as shown in FIG. Thereafter, as shown in FIG. 6 (b), a concave portion 123 having a depth L8 is provided on one end surface of the solid material 120 by the punch 122, and a corner portion is formed at the boundary between the other end surface and the outer peripheral surface. An intermediate material 125 having a diameter φG, in which 124 is molded, is obtained.

Next, as shown in FIG. 6C, the intermediate material 125 is set between the moving side die 126 and the fixed side die 127 having a tapered inner peripheral surface, and the moving side die 126 is fixed together with the punch 128. Move toward the side die 127. As a result, the intermediate material 125 is ironed into a taper shape having an axial length L7 (L6> L7) and a small diameter side diameter φH (φH <φG), and between the moving side die 126 and the fixed side die 127. The surplus meat 129 bulges into the gap D. Then, the surplus 129 is removed and the outer peripheral surface is finished in a subsequent grinding step.
JP-A-8-257667 Japanese Patent Publication No. 3-23250

  By the way, in the manufacturing method of the conventional cylindrical roller, spherical roller and tapered roller described above, the extra space 105 at the time of molding is formed in the gap D between the moving side dies 101, 111, 126 and the fixed side dies 102, 112, 127. 112, 127 bulge out, and in the subsequent process, it is necessary to increase the grinding allowance for the removal of the surpluses 105, 115, 129 and the finishing of the outer peripheral surface, which increases the manufacturing cost. is there.

  In addition, since the surplus at the time of molding is expanded in the gap D between the moving dies 101, 111, 126 and the fixed dies 102, 112, 127, the molding area increases and the molding load is not increased. There is a problem that it becomes stable. In particular, in the manufacture of tapered rollers, on the small diameter side of the intermediate material 125, iron molding is performed while moving the surplus portion of the outer diameter portion to the gap D, so that the molding load increases.

  Further, in the spherical roller manufacturing method, since the inner peripheral surfaces of the dies 111 and 112 for forming the outer peripheral surface of the solid material 110 are concave spherical surfaces, the solid material 110 and the dies 111 and 112 are formed. The gap E between the two is large. Therefore, when the moving side die 111 is moved toward the fixed side die 112 to perform the press molding, the material flow in the axial direction due to the extrusion forming of the concave portion 114 and the gap between the solid material 11 and each of the dies 111 and 112 are performed. There is a radial material flow that attempts to fill E. 5B, the material flow in the axial direction and the radial direction is combined, and as shown in FIG. 5C, a lacking portion 116 may be generated in the inner peripheral portion of the recess 114. There is.

  The present invention has been made to eliminate such inconveniences, and its purpose is to reduce the manufacturing cost by reducing the machining cost of the grinding process in the subsequent process and to stabilize the molding load. An object of the present invention is to provide a roller bearing roller that can be used and a method for manufacturing the same.

The above object of the present invention is achieved by the following configurations.
(1) A method of manufacturing a roller bearing roller for manufacturing a roller from a solid material by cold forging,
A step of extruding a bottomed hole in at least one axial end surface of the solid material; and
Sizing molding by compressing the extruded material using the moving side mold and the stationary side mold in the axial direction;
With
In the sizing molding process, the axial gap during molding of the moving side mold and the fixed side mold is located in the axial part where the bottomed hole is not formed in the extrusion molding, and the inner peripheral surface of the bottomed hole is A method for manufacturing a roller bearing roller, wherein at least a part of the roller bearing is applied in an unconstrained state.
(2) The roller is a cylindrical or spherical roller,
In the extrusion process, bottomed holes are formed on both ends of the solid material in the axial direction.
The method for producing a roller bearing roller according to (1), wherein the depth of the bottomed hole after the sizing molding step is ¼ or more of the total length of the roller.
(3) The sizing molding process uses a moving side mold and a fixed side mold each having an inner circumferential surface having an axial length longer than the depth of the bottomed hole, and the axial end surface, corner portion, and outer circumference. The method for producing a roller bearing roller according to (2), wherein the surface is molded simultaneously.
(4) The roller is a tapered roller,
The extrusion process forms a bottomed hole on one axial end surface of a solid material,
The method for producing a roller bearing roller according to (1), wherein the depth of the bottomed hole after the sizing molding step is ½ or more of the total length of the roller.
(5) further comprising the step of indenting the extruded material with a taper-shaped mold,
The sizing molding process is separate from the indentation molding process or before the end of the same process. A small-diameter side and a large-diameter side end face, a corner part, and an outer peripheral face are simultaneously formed using a fixed mold having a tapered inner peripheral face having an axial length (4). A method for producing a roller bearing roller according to claim 1 .

  According to the present invention, in the sizing molding process, the axial gap during molding between the moving-side mold and the fixed-side mold is located in the axial direction portion where the bottomed hole is not formed by the extrusion molding process. Since at least a part of the inner peripheral surface of the bottom hole is applied in an unconstrained state, surplus meat can be released to the inner peripheral surface of the bottomed hole. As a result, there is no bulge in the gap between the moving side mold and the fixed side mold, and the subsequent grinding process can only be a finishing process on the outer peripheral surface of the roller. The manufacturing cost can be reduced by decreasing the number.

  Further, since no surplus is left in the gap between the moving side mold and the fixed side mold, the molding load can be stabilized without increasing the molding area.

  Furthermore, since the volume of the roller is reduced by extruding the depth of the bottomed hole deeply, the weight of the roller and thus the bearing can be reduced, and the material cost of the solid material can be reduced.

  Hereinafter, a roller bearing and a manufacturing method thereof according to each embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)
The manufacturing method of the cylindrical roller which concerns on 1st Embodiment is manufactured by performing cold forging from the solid raw material 10, and as shown to Fig.1 (a) and FIG.1 (b), the extrusion die 11 is made. And a process of extruding the bottomed holes 12 on both end surfaces in the axial direction of the solid material 10 and extruding using a moving side mold 13 and a fixed side mold 14 as shown in FIG. A step of compressing the intermediate material 15 in the axial direction and performing sizing molding.

  As shown in FIGS. 1 (a) and 1 (b), an extrusion mold 11 used in the extrusion process includes a die 20 having a cylindrical inner peripheral surface corresponding to the outer peripheral surface of the solid material 10. And a pair of punches 21 for extruding the bottomed holes 12 at both axial end surfaces of the solid material 10 set on the die 20.

  Further, as shown in FIG. 1 (c), the moving side mold 13 used in the sizing molding step includes one axial end surface 33a of the cylindrical roller 30, a curved corner portion 34a, and an outer periphery on one end surface side. A cylindrical moving-side die 22 having a mold surface corresponding to the surface 35a, and a punch 23 having a shape corresponding to the opening edge of the bottomed hole 31 of the cylindrical roller 30 that advances and retreats in the moving-side die 22. With.

The fixed-side mold 14 includes a cylindrical fixed-side die 24 having a mold surface corresponding to the other axial end surface 33b of the cylindrical roller 30, a curved corner portion 34b, and an outer peripheral surface 35b on the other end surface side. And a punch 25 having an edge portion that has a shape corresponding to the opening edge of the bottomed hole 31 of the cylindrical roller 30. Here, the punch 25 also acts as a knockout pin when releasing the cylindrical roller 30 after sizing molding.
The mold surfaces of the moving side mold 13 and the fixed side mold 14 correspond to the shape of the cylindrical roller 30 before finishing, and in the following embodiments, the moving side mold and the fixed side mold are also used. Each mold surface corresponds to the roller shape before finishing.

  The relationship between the depth L4 ′ of the mold surface of the moving die 22 and the depth L4 of the mold surface of the fixed die 23 and the depth L3 of the bottomed hole 32 of the cylindrical roller 31 obtained in the sizing molding process is L3 < L4 ′ and L4 are set, and the relationship between the depth L4 ′ and the depth L4 and L5 of the intermediate material 15 is also set to L5 <L4 ′ and L4. Further, the relationship between the depth L4 ′ of the mold surface of the moving die 22 and the depth L4 of the mold surface of the fixed die 23 is set to L4 ′ <L4.

Next, the manufacturing method of the cylindrical roller 30 will be described in detail for each process.
First, in the extrusion forming step, as shown in FIG. 1A, a solid material 10 having an axial length L is set in an extrusion mold 11. Here, the axial length L of the solid material 10 is shorter than the axial length L6 of the conventional material 100 (see FIG. 4A).

  Then, as shown in FIGS. 1A and 1B, a bottomed hole 12 having a depth L5 is formed on both axial end surfaces of the solid material 10 by a pair of punches 21, and the intermediate material 15 is formed. obtain. At that time, the axial length L1 of the intermediate material 15 is longer than the total length L2 of the cylindrical roller 41 (L2 <L1), and the depth L5 of the bottomed hole 12 is the conventional recess 104 (see FIG. 4B). ) Deeper than depth L8.

  Next, in the sizing molding step, as shown in FIG. 1C, the intermediate material 15 released from the extrusion mold 11 is set in the moving side mold 13 and the fixed side mold 14, and the moving side die 22 is set. Then, the moving side mold 13 including the punch 23 is pushed into the fixed side mold 14 to compress the intermediate material 15 in the axial direction.

  At this time, the axial gap C during molding of the moving side mold 13 and the fixed side mold 14 is located in the axial direction portion where the bottomed hole 12 of the intermediate material 15 is not formed, and the bottomed hole 12 is formed. Sizing is performed in an unconstrained state except for the holding portion (opening edge) of the punch 23 on the inner peripheral surface.

  Here, when the cross-sectional area of the AA part where the bottomed hole 12 is not formed is compared with the cross-sectional area of the BB part where the bottomed hole 12 is formed, the cross-sectional area of the AA part is large. Therefore, when the intermediate material 15 is pushed into the stationary mold 14 side by the moving side mold 13, the AA portion having a large cross-sectional area does not cause plastic deformation because the stress is small, but the B- The B part causes plastic deformation because of the large stress. As a result, the axially opposite end surfaces 33a, 33b, the curved corner portions 34a, 34b, and the outer peripheral surfaces 35a, 35b of the cylindrical roller 30 are simultaneously formed while flowing the surplus wall 32 to the inner peripheral portion of the bottomed hole 12 in the unconstrained state. Molded.

  The cylindrical roller 30 sized in this way is formed such that the depth L3 of the bottomed hole 31 and the total length L2 of the cylindrical roller 30 have a dimensional relationship of L2 / 4 ≦ L3. Further, after the sizing molding, the cylindrical roller 30 is finished on the outer peripheral surface, but the surplus portion 32 at the time of sizing molding remains on the inner peripheral surface of the bottomed hole 31 and is used in this state.

  Therefore, in this embodiment, in the sizing molding step, the axial gap C during molding of the moving side mold 33 and the fixed side mold 34 is in the axial direction portion where the bottomed hole 12 of the intermediate material 15 is not formed. Since the portion other than the opening edge of the inner peripheral surface of the bottomed hole 12 is provided in an unconstrained state, the surplus wall 32 can be released to the inner peripheral surface of the bottomed hole 31 of the cylindrical roller 30. . As a result, the surplus thickness does not swell in the axial gap C between the moving-side mold 33 and the fixed-side mold 34, and the grinding of the post-process is performed on the outer periphery of the roller without the surplus thickness 105 as in the prior art. Only the surface finishing can be performed, and the grinding cost can be reduced and the manufacturing cost can be reduced.

  Further, since no surplus is left in the axial gap between the moving side mold 13 and the fixed side mold 14, the molding load can be stabilized without increasing the molding area.

  Furthermore, since the volume of the cylindrical roller 30 is reduced by extruding the depth of the bottomed hole 31, the weight of the cylindrical roller 30 and eventually the cylindrical roller bearing can be reduced. Cost can be reduced.

(Second Embodiment)
Next, with reference to FIG. 2, the manufacturing method of the spherical roller which concerns on 2nd Embodiment of this invention is demonstrated.

  The spherical roller manufacturing method according to the second embodiment is manufactured by cold forging from a solid material 40, and as shown in FIGS. 2 (a) and 2 (b), an extrusion mold 41 is formed. And a step of extruding a bottomed hole 42 on both end surfaces of the solid material 40 in the axial direction, and an extruding process using a moving side mold 43 and a fixed side mold 44 as shown in FIG. A step of compressing the intermediate material 45 in the axial direction and performing sizing molding.

  As shown in FIGS. 2 (a) and 2 (b), an extrusion mold 41 used in the extrusion process includes a die 50 having a cylindrical inner peripheral surface corresponding to the outer peripheral surface of the solid material 40. And a pair of punches 51 for extruding a bottomed hole 42 at both axial end surfaces of the solid material 40 set in the die 50.

  Further, as shown in FIG. 2C, the moving side mold 43 used in the sizing molding process includes one axial end surface 63a of the spherical roller 60, a curved corner portion 64a, and an outer periphery on one end surface side. A cylindrical moving-side die 52 having a bottomed hemispherical mold surface corresponding to the surface 65a, and an edge having a shape corresponding to the opening edge of the bottomed hole 61 of the spherical roller 60, which advances and retreats in the moving-side die 52. And a punch 53 having

  The fixed side mold 44 is a cylindrical shape having a bottomed hemispherical mold surface corresponding to the other axial end face 63b of the spherical roller 60, a curved corner portion 64b, and an outer peripheral face 65b on the other end face side. A fixed die 54 and a punch 55 that moves forward and backward in the fixed die 54 and has an edge corresponding to the opening edge of the bottomed hole 61 of the spherical roller 60 are provided. Here, the punch 55 also functions as a knockout pin when releasing the spherical roller 50 after sizing molding.

  The relationship between the depth L4 ′ of the mold surface of the moving die 52 and the depth L4 of the mold surface of the fixed die 53 and the depth L3 of the bottomed hole 61 of the spherical roller 60 obtained in the sizing molding process is L3 < L4 ′ and L4 are set, and the relationship between the depth L4 ′ and the depth L4 and L5 of the intermediate material 45 is also set to L5 <L4 ′ and L4. Further, the relationship between the depth L4 ′ of the mold surface of the moving-side die 52 and the depth L4 of the mold surface of the fixed-side die 53 is set to L4 ′ <L4.

Next, the manufacturing method of the spherical roller 60 will be described in detail for each process.
First, in the extrusion molding step, a solid material 40 having an axial length L is set in an extrusion molding die 41 as shown in FIG. Here, the axial length L of the solid material 40 is shorter than the axial length L6 of the conventional solid material 110 (see FIG. 5A).

  Then, as shown in FIGS. 2A and 2B, a bottomed hole 42 having a depth L5 is formed on both axial end surfaces of the solid material 40 by a pair of punches 51, and an intermediate material 45 is formed. obtain. At that time, the axial length L1 of the intermediate material 45 is longer than the total length L2 of the spherical roller 61 (L2 <L1), and the depth L5 of the bottomed hole 42 is the conventional recess 114 (see FIG. 5B). ) Deeper than depth L8.

  Next, in the sizing molding step, as shown in FIG. 2C, the intermediate material 45 released from the extrusion mold 41 is set in the moving side mold 43 and the fixed side mold 44, and the moving side die 52 is moved. Then, the moving side mold 43 including the punch 53 is pushed into the fixed side mold 44 side to compress the intermediate material 45 in the axial direction.

  At this time, the axial gap C during molding of the moving side mold 43 and the fixed side mold 44 is located in the axial direction portion where the bottomed hole 42 of the intermediate material 45 is not formed, and the bottomed hole 42 is formed. The portion other than the holding portion (opening edge) of the punch 53 on the inner peripheral surface is molded in an unconstrained state.

  Here, when the cross-sectional area of the AA portion where the bottomed hole 42 is not formed is compared with the cross-sectional area of the BB portion where the bottomed hole 42 is formed, the cross-sectional area of the AA portion is large. Therefore, when the intermediate material 45 is pushed into the fixed mold 44 side by the moving side mold 43, the AA portion having a large cross-sectional area does not cause plastic deformation because the stress is small, but the B- The B cross section causes plastic deformation because of the large stress. As a result, both the axial end surfaces 63a and 63b of the spherical roller 61, the curved corner portions 64a and 64b, and the outer peripheral surfaces 65a and 65b are simultaneously passed while flowing the surplus wall 62 through the inner peripheral portion of the bottomed hole 42 in the unconstrained state. Molded.

  Further, the spherical roller 60 sized in this way is formed such that the depth L3 of the bottomed hole 61 and the total length L2 of the spherical roller 60 have a dimensional relationship of L2 / 4 ≦ L3. In addition, after the sizing molding, the spherical roller 60 is finished on the outer peripheral surface, but the surplus portion 62 at the time of sizing molding remains on the inner peripheral surface of the bottomed hole 61 and is used in this state.

  Therefore, in the present embodiment, in the sizing molding step, the axial gap C during molding of the moving side mold 43 and the fixed side mold 44 is in an axial part where the bottomed hole 42 of the intermediate material 45 is not formed. Since the portion other than the opening edge of the inner peripheral surface of the bottomed hole 42 is formed in an unconstrained state, the surplus wall 62 can be released to the inner peripheral surface of the bottomed hole 61 of the spherical roller 60. . As a result, the surplus thickness does not swell in the axial gap C between the moving-side mold 43 and the fixed-side mold 44, and the grinding of the post-process is performed on the outer periphery of the roller without the surplus 115 as in the prior art. Only the surface finishing can be performed, and the grinding cost can be reduced and the manufacturing cost can be reduced.

  Further, since no surplus is left in the axial gap between the moving side mold 43 and the fixed side mold 44, the molding load can be stabilized without increasing the molding area.

  Furthermore, since the volume of the spherical roller 60 is reduced by extruding the depth of the bottomed hole 61, the weight of the spherical roller 60 and eventually the spherical roller bearing can be reduced, and the material of the solid material 40 can be reduced. Cost can be reduced.

  Further, in the extrusion process, the end surface of the solid material 51 is extruded with the outer peripheral surface of the solid material 51 held by the die 56 with almost no gap, and the bottom of the solid material 51 is flowed only in the axial direction. Since the hole 42 is formed, it can be formed without generating the conventional thinned portion 116 as shown in FIG.

(Third embodiment)
Next, with reference to FIG. 3, the manufacturing method of the tapered roller which concerns on 3rd Embodiment of this invention is demonstrated.

  The method for manufacturing a tapered roller according to the third embodiment is manufactured by performing cold forging from a solid material 70. As shown in FIGS. 3 (a) and 3 (b), an extrusion mold 71 is formed. And a step of extruding a bottomed hole 72 on one axial end surface of the solid material 70 and a recess 73 on the other axial end surface, as shown in FIG. The intermediate material 76 extruded using the mold 75 is compressed in the axial direction for sizing molding, and the intermediate material 76 extruded using the moving side mold 74 and the fixed side mold 75 is pushed in. In this embodiment, the sizing molding process and the indentation molding process are performed simultaneously.

  As shown in FIGS. 3 (a) and 3 (b), an extrusion mold 71 used in the extrusion process includes a die 80 having a cylindrical mold surface corresponding to the outer peripheral surface of the solid material 70, and A punch 81 for extruding a bottomed hole 72 on one axial end surface of the solid material 70 set on the die 80 and a punch 82 for extruding a recess 73 on the other axial end surface of the solid material 70 are provided. Yes.

  Further, as shown in FIG. 3C, the moving side die 74 used in the sizing molding step and the pushing step corresponds to the large-diameter side axial end surface 94a of the tapered roller 90 and the curved corner portion 95a. A cylindrical moving side die 83 having a mold surface and a punch 84 having an edge portion that moves forward and backward in the moving side die 83 and holds the concave portion 91 of the tapered roller 90 are provided.

  The fixed-side mold 75 includes an axial end surface 94b on the small diameter side of the tapered roller 90, a curved corner portion 95b, a cylindrical fixed-side die 85 having a tapered mold surface corresponding to the outer peripheral surface 96, And a punch 86 that moves forward and backward in the fixed die 85 and has an edge portion corresponding to the opening edge of the bottomed hole 92 of the tapered roller 90. Here, the punch 86 also functions as a knockout pin when releasing the tapered roller 90 after sizing molding.

  The relationship between the depth L4 of the die surface of the fixed die 85 and the depth L3 of the bottomed hole 91 of the tapered roller 90 obtained in the sizing molding step is set to L3 <L4. The relationship with the depth L5 of the bottomed hole 72 of the intermediate material 76 obtained in the extrusion process is also set to L5 <L4.

Next, the manufacturing method of the tapered roller 81 will be described in detail for each process.
First, in the extrusion molding step, a solid material 70 having an axial length L is set in an extrusion mold 71 as shown in FIG. Here, the axial length L of the solid material 70 is shorter than the axial length L6 of the conventional solid material 120 (see FIG. 6A).

  3 (a) and 3 (b), a bottomed hole 72 having a depth L5 is formed on one end surface in the axial direction of the solid material 70 by the punch 81, and the other axial direction is formed by the punch 82. A recess 73 having a depth L7 is formed on the end surface to obtain an intermediate material 76. At that time, the axial length L1 of the intermediate material 76 is longer than the total length L2 of the tapered roller 81 (L2 <L1), and the depth L5 of the bottomed hole 72 is the conventional recess 123 (see FIG. 6B). The depth L8 of the recess 72 is equal to the depth L8 of the conventional recess 123 (see FIG. 6B).

  Next, in the sizing molding step and the pressing step, as shown in FIG. 3C, the intermediate material 76 released from the extrusion molding die 71 is placed at the end on the bottomed hole 72 side of the fixed side die 75. The moving side die 74 including the moving side die 83 and the punch 84 is pushed into the fixed side die 75 side by being reversed and set to the moving side die 74 and the fixed side die 75 so as to be held by the mold surface. The intermediate material 76 is compression-molded in the axial direction, and the end portion on the bottomed hole 72 side is subjected to indentation molding (scoring molding).

  At this time, the axial gap C during molding of the moving side mold 74 and the fixed side mold 75 is located in the axial direction portion where the bottomed hole 72 of the intermediate material 76 is not formed, and the bottomed hole 72 is formed. The sizing molding is performed in an unconstrained state except the holding portion (opening edge) of the punch 86 on the inner peripheral surface.

  Here, when the cross-sectional area of the AA portion where the bottomed hole 72 is not formed is compared with the cross-sectional area of the BB portion where the bottomed hole 72 is formed, the cross-sectional area of the AA portion is large. Therefore, when the intermediate material 76 is pushed into the fixed die 75 side by the moving side die 74, the AA portion having a large cross-sectional area does not cause plastic deformation because the stress is small, but the B- The portion B undergoes plastic deformation due to a large stress, and the small diameter side and large diameter side end surfaces 94a and 94b and the corner portion 95a of the tapered roller 90 are caused to flow over the inner peripheral portion of the bottomed hole 72 in an unconstrained state. 95b and the outer peripheral surface 96 are formed simultaneously.

  Further, the tapered roller 90 sized in this way is formed so that the depth L3 of the bottomed hole 92 and the total length L2 of the tapered roller 81 have a dimensional relationship of L2 / 2 ≦ L3. Further, after the sizing molding, the tapered roller 90 is finished on the outer peripheral surface, but the surplus portion 93 at the time of sizing molding remains on the inner peripheral surface of the bottomed hole 92 and is used in this state.

  Therefore, in the present embodiment, the sizing molding step is performed in such a manner that the axial gap C during molding of the moving side mold 74 and the fixed side mold 75 is in the axial direction portion where the bottomed hole 72 of the intermediate material 76 is not formed. Since the portion other than the opening edge of the inner peripheral surface of the bottomed hole 72 is formed in an unconstrained state, the surplus wall 93 can be released to the inner peripheral surface of the bottomed hole 92 of the tapered roller 90. . As a result, there is no swelling of the surplus in the axial gap between the moving-side mold 74 and the fixed-side mold 75, and the post-grinding process can be performed in a roller outer peripheral surface without the surplus 129 as in the prior art. Therefore, the manufacturing cost can be reduced by reducing the grinding cost.

  Further, since no surplus is left in the axial gap between the moving-side mold 74 and the fixed-side mold 75, the molding load can be stabilized without increasing the molding area. When performing ironing on the small-diameter side, the excess load is formed while being moved to the inner peripheral surface of the bottomed hole 92 in an unconstrained state, so that the molding load can be reduced.

  Furthermore, since the volume of the tapered roller 90 is reduced by extruding the depth of the bottomed hole 72, the weight of the tapered roller 90 and eventually the tapered roller bearing can be reduced. Cost can be reduced.

  Note that the sizing molding step and the pressing step are not necessarily performed simultaneously, and the sizing molding step may be performed after the pressing step.

The present invention is not limited to the embodiments described above, and modifications, improvements, and the like can be made as appropriate.
In the above embodiment, when forming a recess in which the claw portion of the cage is inserted and held in the bottomed hole formed in the axial end surface of each roller, the sizing is performed in a state where the punch of the moving die is pushed in. What is necessary is just to shape | mold a recessed part by performing a formation process.

  In addition, when the roller of the present invention is applied to a roller bearing in which a pin-type cage is used, both end surfaces may be penetrated by drilling the bottom surface of the bottomed hole after the sizing molding process. Also in this case, each roller can be used in a state in which the surplus is left by securing the inner diameter of the surplus according to the outer peripheral surface of the pin.

BRIEF DESCRIPTION OF THE DRAWINGS It is for demonstrating the manufacturing method of the cylindrical roller which is the 1st Embodiment of this invention, (a) is a sectional view showing an extrusion molding process, (c) is a sizing molding process at the time of material injection | throwing-in. It is. It is for demonstrating the manufacturing method of the spherical roller which is the 2nd Embodiment of this invention, (a) is a raw material injection | pouring, (b) is an extrusion molding process, (c) is sectional drawing showing a sizing molding process It is. It is for demonstrating the manufacturing method of the tapered roller which is the 3rd Embodiment of this invention, (a) is at the time of raw material introduction, (b) is an extrusion molding process, (c) is a sizing molding process and an indentation molding process. It is sectional drawing showing. It is for demonstrating the manufacturing method of the conventional cylindrical roller, (a) is a cross-sectional view showing a sizing shaping | molding process at the time of raw material injection | bending, (b). It is for demonstrating the manufacturing method of the conventional spherical roller, (a) is a cross-sectional view showing a sizing shaping | molding process at the time of raw material input, (c) is F section detail drawing of (b). . It is for demonstrating the manufacturing method of the conventional tapered roller, (a) is a cross-sectional view showing the extrusion molding process, (c) is a sizing molding process, and an ironing process at the time of material injection | throwing-in.

Explanation of symbols

10, 40, 70 Solid material 12, 31, 42, 61, 72, 92 Bottomed holes 13, 43, 74 Moving-side mold 14, 44, 75 Fixed-side mold 30 Cylindrical roller 60 Spherical roller 90 Conical roller 32 , 62,93 Extra meat

Claims (5)

A roller bearing roller manufacturing method for manufacturing a roller from a solid material by cold forging,
Extruding a bottomed hole in at least one axial end surface of the solid material; and
Sizing molding by compressing the extruded material in the axial direction using a moving side mold and a fixed side mold;
With
In the sizing molding step, an axial gap during molding of the moving side mold and the fixed side mold is located in an axial portion where the bottomed hole is not formed in the extrusion molding, and the bottomed A method for manufacturing a roller bearing roller, wherein at least a part of an inner peripheral surface of the hole is applied in an unconstrained state. The roller is a cylindrical or spherical roller,
In the extrusion molding step, the bottomed holes are respectively formed on both end surfaces in the axial direction of the solid material,
2. The method for manufacturing a roller bearing roller according to claim 1, wherein a depth of the bottomed hole after the sizing molding step is ¼ or more of a total length of the roller.   The sizing molding step uses the moving side mold and the fixed side mold each having an inner circumferential surface having an axial length longer than the depth of the bottomed hole, and an axial end surface and a corner portion. The method for manufacturing a roller bearing roller according to claim 2, wherein the outer peripheral surface is molded simultaneously. The roller is a tapered roller,
In the extrusion molding step, the bottomed hole is formed on one axial end surface of the solid material,
2. The method for manufacturing a roller bearing roller according to claim 1, wherein a depth of the bottomed hole after the sizing molding step is ½ or more of a total length of the roller. A step of indenting the extruded material with a taper-shaped mold, and further comprising:
The sizing molding step is separate from the indentation molding step or before the end of the same step, the movable mold capable of contacting the large diameter side end surface and the small diameter side end surface can be contacted, and the bottomed hole Forming the small-diameter side and large-diameter side end surfaces, the corner portion, and the outer peripheral surface at the same time using the fixed-side mold having a tapered inner peripheral surface having an axial length longer than the depth of The manufacturing method of the roller for roller bearings of Claim 4 characterized by the above-mentioned .

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