JP2016128709A - Thrust roller bearing cage and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thrust roller bearing retainer that reduces running torque, and a method of manufacturing the same.SOLUTION: A thrust roller bearing retainer (11) according to the present invention is provided for a thrust roller bearing (20), and provided with a plurality of pockets (21) for housing rollers (13), and comprises an outer-dimeter region bent part (41) bent to an inner diameter side about a bending origin that is a ring-shaped groove provided at an outer diameter side with respect to the pockets (21), and a projection part (44) that is provided at a tip of the outer diameter region bent part (41) at a position aligned with each of the pockets (21), and projects to the inner diameter side from an outer diameter-side edge of the pocket (21) to come into contact with an end face (16) of the roller (13) housed in the pocket (21), a trace (29) of a groove being left at the bending origin.SELECTED DRAWING: Figure 3

Description

  TECHNICAL FIELD The present invention relates to a thrust roller bearing retainer (hereinafter sometimes simply referred to as “retainer”) and a method for manufacturing the same, and in particular, a thrust roller bearing retainer manufactured using a press, and It relates to the manufacturing method.

  For example, a thrust roller bearing that receives a thrust load may be disposed at a location where a thrust load is applied in an automatic transmission for an automobile, a compressor for a car air conditioner, or the like. Such thrust roller bearings are desired to reduce the rotational torque of the bearings from the viewpoint of reducing fuel consumption and saving labor. The thrust roller bearing includes a bearing ring disposed in the rotation axis direction, a plurality of needle rollers that roll on the raceway surface of the bearing ring, and a cage that holds the plurality of needle rollers. The cage may be manufactured by bending a steel plate and then removing a pocket to accommodate the rollers.

  For example, Japanese Patent Application Laid-Open No. 10-220482 (Patent Document 1) discloses a technique related to a cage provided in such a thrust roller bearing. The cage for thrust roller bearings of Patent Document 1 is composed of an annular main body that is punched or punched, and a convex portion provided on the outer diameter side of the annular main body, and the convex portion is folded back of the annular main body. The portions located in the respective pockets on the end face on the outer diameter side are provided so as to protrude in the inner diameter direction so that the tip faces the vicinity of the center of the roller.

Japanese Patent Laid-Open No. 10-220482

  In order to reduce the rotational torque, in Patent Document 1, it is desirable that the tip of the convex portion is in contact with the vicinity of the center of the outer peripheral side end surface of the roller. However, in Patent Document 1, the position of the tip of the convex portion may deviate from a desired position, and the rotational torque may not be sufficiently reduced.

  Accordingly, an object of the present invention is to provide a thrust roller bearing retainer that reduces rotational torque and a method of manufacturing the same.

  In the above Patent Document 1, the fact that the tip of the convex portion does not contact the center of the outer diameter side end surface of the roller is because the area on the outer diameter side from the folding position of the annular body is small, that is, the folding height is low. The present inventor has found that the folding position is caused to deviate from a desired position because it is difficult to fold the sheet. Therefore, the inventor of the present invention has completed the present invention as a result of earnestly researching means for improving the position accuracy of folding the annular body and easily folding the annular body.

  That is, the cage of the thrust roller bearing of the present invention is a thrust roller bearing cage provided in the thrust roller bearing and provided with a plurality of pockets for accommodating the rollers, and is provided on the outer diameter side of the pockets. An outer diameter region bent portion formed by bending toward the inner diameter side with a circular groove as a starting point, and an end surface of a roller provided at the tip of the outer diameter region bent portion at a position aligned with each pocket and accommodated in the pocket And a protruding portion that protrudes toward the inner diameter side from the edge on the outer diameter side of the pocket so as to be in contact with the groove, and a trace of the groove remains at the bending start point.

  A method for manufacturing a cage for a thrust roller bearing according to the present invention is a method for manufacturing a cage for a thrust roller bearing provided in a thrust roller bearing and provided with a plurality of pockets for accommodating the rollers, and includes the following steps. ing. Prepare the cage material to be the cage. The cage material is formed with an outer shape having a portion which becomes a protruding portion protruding from the outer edge of the pocket toward the inner diameter side so as to contact the end face of the roller accommodated in the pocket. A pocket is formed for the cage material. An annular groove is formed on the outer diameter side of the pocket with respect to the cage material. Using the groove as a bending starting point, a region of the cage material located on the outer diameter side of the pocket is bent toward the inner diameter side to form an outer diameter region bent portion.

  According to the cage of the thrust roller bearing and the manufacturing method thereof according to the present invention, the outer diameter region bent portion is formed by bending the annular groove provided on the outer side of the pocket toward the inner diameter side with the bending starting point. For this reason, since an annular groove serves as a folding position, it is possible to prevent the folding position from shifting. Moreover, even if the bending height is low, it becomes easy to bend by the annular groove. Therefore, the annular groove can improve the positional accuracy of the outer diameter region bent portion and can be easily folded back, so that the protrusion provided at the tip of the outer diameter region bent portion is positioned at the center of the outer diameter side end surface of the roller. Since the contact can be made in the vicinity, the rotational torque can be reduced.

  In the cage of the thrust roller bearing of the present invention, preferably, a region of the projecting portion that comes into contact with the end surface of the roller is subjected to surface pressing.

  Preferably, the method for manufacturing a cage for a thrust roller bearing according to the present invention further includes a step of performing a surface pressing process on a region of the projecting portion that contacts the end surface of the roller.

  Thereby, since the area | region which contacts a roller end surface among protrusions is surface-press-processed, at the time of rotation of a bearing, an oil film is slid by sliding with the area | region which contacts a roller end surface of a roller end surface during a protrusion part. Can be cut off. If it does so, the lubricity of this contact area | region will improve and the aggressiveness to the protrusion part of what is called a holder | retainer of a roller can be relieved. Therefore, such a thrust roller bearing retainer can further reduce the rotational torque of the bearing.

  The above-mentioned “surface pressing process” means that the protruding portion is formed by utilizing the outer diameter surface of the mold that plays a role of a stopper for regulating the amount of collapse in the process of forming the outer diameter region bent portion. By pressing in the diameter expansion direction, it means a process of smoothing the roughness shape of the surface before and after the process. Specifically, the press shear surface or fractured surface formed during the step of forming the outer shape can be smoothed to an arithmetic average roughness Ra (JIS B 0601) of about 2 μm or less by surface pressing.

  According to the cage of the thrust roller bearing and the manufacturing method thereof according to the present invention, the rotational torque can be reduced.

It is a figure which shows a part of cage | basket of the thrust roller bearing which concerns on one Embodiment of this invention. It is sectional drawing of the cage | basket of the thrust roller bearing shown in FIG. It is an expanded sectional view which shows a part of cage | basket of the thrust roller bearing shown in FIG. It is a flowchart which shows the typical process of the manufacturing method of the retainer of the thrust roller bearing which concerns on one Embodiment of this invention. It is sectional drawing of the cage | basket material after performing an uneven | corrugated shape formation process. It is an expanded sectional view which expands and shows a part of cage material after performing a pilot hole formation process. It is an expanded sectional view which expands and shows a part of cage material after performing an external shape formation process. It is a figure which shows a part of cage material after performing a pocket formation process. It is an expanded sectional view which expands and shows a part of cage material after performing a pocket formation process. It is an expanded sectional view which expands and shows a part of cage material of the middle stage of an outer diameter area | region bending process. It is an expanded sectional view which shows the state which performs an outer diameter area | region bending process. It is an expanded sectional view which shows the state which performs an outer diameter area | region bending process. It is an expanded sectional view which expands and shows a part of cage material after performing an outer diameter area | region bending process. It is an expanded sectional view which expands and shows a part of cage material after performing an outer diameter area | region bending process. It is an expanded sectional view which shows the state which implements an outer diameter area | region bending process. It is an expanded sectional view which shows the state which performs a surface pressing process. It is an expanded sectional view which expands and shows the front-end | tip part of the outer diameter area | region bending part after performing a surface pressing process. It is sectional drawing which shows a part of cage | basket of the thrust roller bearing which concerns on other embodiment of this invention. It is a figure which shows a part of cage | basket of the thrust roller bearing which concerns on other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

FIG. 1 is a view showing a part of a cage 11 of a thrust roller bearing according to an embodiment of the present invention. FIG. 1 is a view of the cage 11 as seen from the rotation axis direction of the cage 11. FIG. 2 is a sectional view of the cage 11 of the thrust roller bearing shown in FIG. FIG. 2 is a case of cutting along a section indicated by II-II in FIG. Specifically, a cross section of a portion where a pocket described later is formed in the right region of FIG. 2 is shown, and a cross section of a portion where a column portion described later is formed in the left region of FIG. FIG. 3 is an enlarged sectional view showing a part of the cage 11 of the thrust roller bearing shown in FIG. FIG. 3 is an enlarged cross-sectional view of a region indicated by III in FIG. 2 and 3, the rotation axis 12 of the cage 11 is indicated by a one-dot chain line. Further, from the viewpoint of easy understanding, in FIG. 3, one of a pair of track rings 14 and 15 arranged on both sides of the needle roller 13 accommodated in a pocket 21 described later and the rotating shaft direction of the retainer 11. The part is illustrated. Note that the front and back direction of the paper surface in FIG. 1 and the vertical direction of the paper surface in FIG. 2 and FIG. Further, the direction of the direction or vice versa indicated by the arrow A ₁ in FIG. 1, a circumferential direction. From the viewpoint of easy understanding, the upper side in FIG. 2 and FIG. 3 is the upper side in the axial direction. That is, the direction indicated by arrow A ₂ in FIG. 2 and FIG. 3, the upward direction. Further, the horizontal direction in FIG. 2 and FIG. 3 is the radial direction. Direction indicated by arrow A ₃ in FIG. 3, the outer diameter direction.

  With reference to FIGS. 1-3, the structure of the cage | basket 11 of the thrust roller bearing which concerns on one Embodiment of this invention is demonstrated first. The thrust roller bearing retainer 11 according to an embodiment of the present invention has a disk shape, and a through hole 22 is provided in a central region thereof so as to penetrate straight in the thickness direction. A rotation shaft (not shown) is disposed in the through hole 22.

  The retainer 11 is provided at intervals in the circumferential direction so as to form a pair of annular portions 23 and 24 having different diameters and a pocket 21 that accommodates the needle rollers 13. And a plurality of column portions 25 to be connected. In this case, although a part of the illustration is omitted, the retainer 11 is provided with 28 pockets 21 and 28 column portions 25.

  The pocket 21 has a substantially rectangular shape when viewed from the axial direction. The pockets 21 are arranged radially about the rotation axis 12 of the cage 11. On the side wall surface of the pocket 21, an upper roller stopper 26 that prevents the needle rollers 13 accommodated in the pocket 21 from falling off in the axial direction and an axial direction of the needle rollers 13 accommodated in the pocket 21. Lower roller stoppers 27 and 28 are provided to prevent falling off. The upper roller stopper 26 is provided at the center in the radial direction of the pocket 21. Further, the lower roller stopper 27 is provided on the inner diameter side of the pocket 21, and the lower roller stopper 28 is provided on the outer diameter side of the pocket 21. The upper roller stopper 26 and the lower roller stoppers 27 and 28 are provided on the side wall surfaces on both sides in the circumferential direction of the pocket 21 so as to protrude toward the pocket 21.

  The needle rollers 13 are accommodated so as to be pushed into the pockets 21. The shape of the end face of the needle roller 13, specifically, the end face 16 located on the bearing outer side and the end face 17 located on the bearing inner side is flat.

  The cage 11 is formed with a concavo-convex shape obtained by bending a plate material several times in the plate thickness direction and bending it. Specifically, the retainer 11 includes four disk portions 31, 32, 33, and 34 that extend in the radial direction, and four cylindrical portions 36, 37, 38, and 39 that extend in the axial direction. The four disk parts 31 to 34 have an inner diameter in the order of the first disk part 31, the second disk part 32, the third disk part 33, and the fourth disk part 34 from the inner diameter side. Is configured to be large. The four cylindrical portions 36 to 39 are arranged in the order of the first cylindrical portion 36, the second cylindrical portion 37, the third cylindrical portion 38, and the fourth cylindrical portion 39 from the inner diameter side. The first cylindrical part 36 and the second cylindrical part 37 are configured to extend straight in the axial direction. The third cylindrical portion 38 is configured to be slightly inclined so that the inner diameter side portion is located on the lower side in the axial direction than the outer diameter side portion. On the other hand, the fourth cylindrical portion 39 located on the outermost diameter side is configured to be slightly inclined so that the inner diameter side portion is located on the upper side in the axial direction than the outer diameter side portion. The above-described upper roller stopper 26 is provided on the third disk portion 33. Further, the lower roller stopper 27 is provided in the second disc portion 32, and the lower roller stopper 28 is provided in the fourth disc portion 34. The annular portion 23 on the inner diameter side includes the first disc portion 31, a part of the second disc portion 32, the first cylindrical portion 36, and the second cylindrical portion 37. . Further, the annular portion 24 on the outer diameter side described above includes a part of the fourth disc portion 34, an outer diameter region bent portion 41 described later, and a protruding portion 44 described later. The column 25 described above includes a part of the second disk part 32, a third disk part 33, a part of the fourth disk part 34, a third cylindrical part 38, and a fourth cylindrical part. 39.

  The retainer 11 includes an outer diameter region bent portion 41 that is formed by bending an outer diameter side region of the retainer 11 toward an inner diameter side. The outer diameter region bent portion 41 is an upright wall portion that rises in the axial direction, and is formed to extend in a ring shape. Specifically, the outer-diameter region bent portion 41 is formed by bending toward the inner diameter side with an annular groove provided on the outer diameter side from the pocket 21 as a starting point. As shown in FIG. 3, an annular groove trace 29 remains at the bending start point. The trace 29 is a thin part, a compression trace, or the like.

  The outer diameter region bent portion 41 of the present embodiment is formed by obliquely bending a region located on the outer diameter side of the pocket 21 toward the inner diameter side. Specifically, the outer diameter region bending portion 41 bends the outer diameter side end portion of the fourth disc portion 34 disposed on the outermost diameter side at a predetermined angle toward the upper side in the axial direction. It is formed.

The angle of the outer diameter region bent portion 41, that is, the angle between the surface 42 located on the inner diameter side of the outer diameter region bent portion 41 and the upper surface 43 of the fourth disc portion 34 is shown in FIGS. The angle B ₁ in 3 is 0 and may be 0 °, but is preferably an acute angle.

  A protruding portion 44 is provided at the tip of the outer diameter region bent portion 41 at a position aligned with each of the pockets 21. That is, the protrusion 44 is directed radially inward at a position aligned with each pocket 21. The position aligned with the pocket 21 is a position where the outer peripheral edge of the protrusion 44 overlaps the outer peripheral edge of the pocket 21. In other words, the inner edge of the outer diameter region bent portion 41 overlaps the outer edge of the pocket 21.

  The protruding portion 44 protrudes from the edge on the outer diameter side of the pocket 21 toward the inner diameter side so as to contact the end face 16 of the roller 13 accommodated in the pocket 21. That is, each protrusion 44 abuts against the end face of the roller accommodated in each pocket 21 and restricts the movement of the roller in the radially outward direction. Specifically, the protruding portion 44 has a shape extending continuously from the inner peripheral side edge of the outer diameter region bent portion 41 to the inner diameter side. That is, the outer diameter region bent portion 41 and the protruding portion 44 are integrally formed.

  The protruding portion 44 is formed so that the apex of the protruding portion 44 is located at the center in the circumferential direction of the pocket 21 at the circumferential position. Specifically, the corner portion 45 on the surface 42 side (the corner portion 45 located on the innermost diameter side of the protruding portion 44), which is the portion positioned on the innermost diameter side of the protruding portion 44, accommodates the pocket 21. The needle roller 13 is provided so as to contact the center of the end surface 16. The corner portion 45 in this case is a corner located on the fourth disc portion 34 side of the protruding portion 44.

  Here, the retainer 11 is provided with three pilot holes 51 and 52. The three pilot holes 51 and 52 serve as alignment engaging portions. In FIG. 1, one of the pilot holes is not shown. The three pilot holes 51 and 52 are provided so as to penetrate straightly in the plate thickness direction at intervals in the circumferential direction. The three pilot holes 51 and 52 are each opened in a round hole shape. The three pilot holes 51 and 52 are provided at approximately equal intervals. In this case, the pilot holes 51 and 52 are provided at intervals of 120 degrees around the rotation axis 12 of the cage 11. Specifically, the pilot holes 51 and 52 are provided at the center in the radial direction in the first disc portion 31 located on the innermost diameter side. As the diameter of the pilot holes 51 and 52, for example, φ2.5 mm or φ3 mm is selected.

  In addition, the thrust roller bearing 20 provided with such a cage 11 is configured to include, for example, a plurality of needle rollers 13, a race ring 14 located on the upper side, and a race ring 15 located on the lower side. . When the thrust roller bearing 20 is in operation, the needle rollers 13 accommodated in the pocket 21 are the raceway surface 18 of the raceway 14 located on the upper side in the axial direction and the raceway ring located on the lower side in the axial direction. Roll on 15 raceway surfaces 19. The cage 11 rotates around the rotation axis 12. Moreover, each needle roller 13 accommodated in the pocket 21 performs a revolving motion while performing a rotation motion. Here, centrifugal force to the outer diameter side acts on the needle rollers 13. The center of the end surface 16 of the needle roller 13 has a protrusion 44 provided on the retainer 11, specifically, a corner 45 positioned on the innermost diameter side of the protrusion 44 provided on the retainer 11. Sliding contact. In other words, the corner 45 of the projecting portion 44 is a region in contact with the end face 16 of the needle roller 13.

  Here, the corner 45 is subjected to surface pressing. By this surface pressing process, the corner portion 45 does not have a sharply pointed portion, and is smoothly connected to the surface constituting the corner portion 45. For this reason, the aggression to the member of the other party which the corner | angular part 45 contacts is relieved.

  Next, a manufacturing method of the thrust roller bearing retainer 11 according to the embodiment of the present invention will be described. The thrust roller bearing retainer 11 is manufactured using a transfer press. The transfer press is a relatively inexpensive press apparatus that is not so complicated in apparatus configuration. FIG. 4 is a flowchart showing typical steps of the method for manufacturing the thrust roller bearing retainer 11 according to the embodiment of the present invention.

  Referring to FIG. 4, first, a cage material that will later become cage 11 is prepared (cage material preparation step: step S1). As this cage material, for example, a thin flat steel plate is used. Here, the cage material is a plate material cut into a substantially rectangular shape at this stage in order to form the final shape of the cage in the subsequent outer shape forming step (step S4). Alternatively, it may be a disk-shaped plate material.

  Next, a concavo-convex shape is formed in the thickness direction on such a cage material (concave / convex shape forming step: step S2). Thereby, even if it is the thin plate-shaped holder | retainer 11, the length dimension of the rotating shaft direction of the holder | retainer 11 can be ensured large, and a roller can be hold | maintained appropriately.

  In this step, specifically, the drawing is performed on the cage material. In this case, the uneven shape can be formed more efficiently. FIG. 5 is a cross-sectional view of the cage material after performing the uneven shape forming step. The cross section shown in FIG. 5 corresponds to the cross section shown in FIG. Specifically, referring to FIG. 5, the flat retainer material 56 is drawn, and the first to fourth disk portions 61 to 64 and the first to fourth cylindrical portions are formed. 66-69 are formed. And the round hole-like through-hole 57 which penetrates in a plate | board thickness direction is provided in the center. That is, in this case, the cage material 56 has a so-called mountain-valley shape that is bent a plurality of times in the axial direction.

  Next, a pilot hole as an engaging portion is formed (pilot hole forming step: step S3). FIG. 6 is an enlarged cross-sectional view showing a part of the cage material 56 after the pilot hole forming step is enlarged. The cross section shown in FIG. 6 corresponds to a portion shown in a region VI in FIG. The pilot hole 71 as the engaging portion is provided so as to penetrate straight in the plate thickness direction at the radial center of the first disc portion 61. A total of three pilot holes 71 are provided at approximately equal intervals with an interval of 120 degrees in the circumferential direction.

  Thereafter, the outer shape of the cage material 56 is formed (outer shape forming step: step S4). FIG. 7 is an enlarged cross-sectional view showing a part of the cage material 56 after the outer shape forming step is performed. The cross section shown in FIG. 7 corresponds to a portion shown in a region VI in FIG. 2, and is a case where the cross section shown by VII-VII in FIG. 8 is cut. In this case, specifically, the retainer material 56 is straightly punched in the thickness direction so that the final outer shape of the retainer 11 is obtained by an outer diameter region bending step (step S7) to be performed later. To form. In this case, the outer shape of the cage material 56 can be formed relatively easily and accurately. In this manner, the outer end 72 of the retainer 11, specifically, the outer end 72 of the fourth disc portion 64 is formed.

  Here, when forming the outer shape, the cage material 56 is punched out so as to form a portion that will later become the protruding portion 70. That is, in this case, the outer shape forming process is also a protruding part forming process for forming the protruding part. FIG. 8 is a view showing a part of the cage material 56 after the pocket forming step performed after the outer shape forming step. FIG. 8 corresponds to FIG. When punching out so as to form the protruding portion 70, the circumferential positioning is performed using the plurality of pilot holes 71. Specifically, a plurality of guide pins (not shown) serving as a so-called pencil-shaped positioning jig whose tip is sharp and gradually increases in diameter in a tapered shape are provided in a plurality of pilot holes 71. Insert gradually from one side in the thickness direction. Then, positioning is performed using a plurality of guide pins, and the entire outer shape is punched out by a punching device (not shown) in consideration of the position, shape, and the like of the protrusion 70. By doing so, even if the positions of the punching device and the cage material 56 are slightly deviated from the positions where the protrusions 70 are provided, the pencil-shaped guide pins with sharp tips are gradually inserted into the pilot holes 71. In the process of being done, punching can be performed by returning the cage material 56 to the correct position where the protrusion 70 should be provided with respect to the positional relationship with the punching device. In this case, since the three pilot holes 71 are provided, rotation of the cage material 56 and the like can be prevented when positioning is performed, and more reliable positioning can be performed.

  Next, a pocket is formed (pocket formation process: step S5). FIG. 9 is an enlarged cross-sectional view showing a part of the cage material after the pocket forming step is enlarged. The cross section shown in FIG. 9 corresponds to the portion shown in region III in FIG. 2, and is a case where the cross section is shown by IX-IX in FIG. In this case, the pocket 73 extends over a part of the second disk part 62, the third disk part 63, a part of the fourth disk part 64, and the third cylindrical part 68, and the The pocket material is formed so as to penetrate the retainer material 56 straightly in the plate thickness direction over the four cylindrical portions 69. Here, although not shown in FIG. 9, an upper roller stopper and a lower roller stopper having a shape protruding inward in the circumferential direction of the pocket 73 are formed at the same time. That is, the pocket is removed along the outer shape of the needle roller 13 accommodated in the pocket 73 in consideration of the shapes of the upper roller stopper and the lower roller stopper. A plurality of pockets 73 may be formed simultaneously by removing the pockets, or one pocket 73 may be formed one by one.

  Here, also when the pocket 73 is formed in the cage material 56, the pilot hole 71 is used to align the punching device (not shown) for punching the pocket with the cage material 56 to be punched. That is, the pocket 73 is formed with reference to the position where the pilot hole 71 is provided. Also in this case, the circumferential positioning is performed using the plurality of pilot holes 71 in the same manner as in the outer shape forming process described above. Specifically, similarly to the above, a plurality of guide pins as sharp pencil-shaped positioning jigs are prepared, and the tips are gradually inserted into the plurality of pilot holes 71 from one side in the plate thickness direction. Then, positioning is performed by a plurality of guide pins, and the pocket 73 is punched out by a punching device in consideration of the position, shape, etc. of the pocket 73. By doing so, it is possible to make the positional relationship between the formed pocket 73 and the formed protrusion 70 appropriate by aligning the circumferential phases of the provided pocket 73 and the protrusion 70. For this reason, in the positional relationship between the protrusion 70 to be formed and the pocket 73 to be formed, the protrusion 70 can be formed accurately and efficiently, and the protrusion 44 (see FIG. 3) can be accurately formed at an appropriate location. ) Is formed, the end surface 16 of the needle roller 13 and the protruding portion 44 can be appropriately brought into contact with each other during the operation of the bearing. A plurality of pockets 73 may be formed by punching at the same time, or the pockets 73 may be formed by punching one by one.

  In the present embodiment, a pilot hole 71 is formed in a region on the inner diameter side of the pocket 73. In this case, the pilot hole 71 can be formed by effectively using the space that the cage 11 has.

  Further, in the present embodiment, the pilot hole 71 is formed at a position avoiding the place where the pocket 73 is provided in the circumferential direction. In this case, a local decrease in strength can be avoided in the circumferential direction of the cage 11. The positional relationship with the pilot hole 71 is arbitrarily determined. In this case, specifically, the plurality of pockets 73 are formed such that the pilot hole 71 is disposed at a position corresponding to the center in the circumferential direction between the adjacent pockets 73.

  Next, as shown in FIGS. 8 and 9, an annular groove 79 is formed on the outer diameter side of the pocket 73 in the cage material (groove forming step: step S6). In this step (step S6), an annular groove 79 is formed at a position to be a starting point for forming the outer diameter region bent portion 41 in the outer diameter region bending step (step S7) described later. The method for forming the groove 79 is not particularly limited, and press working, cutting, or the like is employed, and it is preferable to press with a ring-shaped wedge. The shape of the groove 79 is not particularly limited, and the groove bottom may be pointed or curved. The order of steps S4 to S6 is not particularly limited.

  Next, with the groove 79 as a starting point of bending, a region located on the outer diameter side of the pocket 73 in the cage material 56 is bent toward the inner diameter side to form an outer diameter region bent portion (outer diameter region bending step) (step) S7). In this step, since the groove 79 is used as the bending start point, the bending position can be easily controlled. Therefore, the position accuracy can be improved and the outer diameter side region of the cage material 56 can be easily bent inward. In this step, it is preferable to bend the inner diameter side obliquely at an acute inclination angle to form the outer diameter region bent portion.

FIG. 10 is an enlarged cross-sectional view showing a part of the cage material in an intermediate stage of the outer diameter region bending process. 11 and 12 are enlarged cross-sectional views showing a state in which the outer diameter region bending step is performed. 13 and 14 are enlarged cross-sectional views showing a part of the cage material 56 after the outer diameter region bending step is enlarged. The cross section shown in FIGS. 10 and 13 corresponds to a portion shown in a region VI in FIG. The cross section shown in FIG. 14 corresponds to the portion shown in region III in FIG. The cross section shown in FIGS. 11 and 12 shows the positional relationship between the holding member 101, 102 and the pressing member 103, the outer diameter side region of the cage material 56 corresponding to the portion shown in the region VI in FIG. Show. Here, as shown in FIG. 10, the end portion 72 on the outer diameter side of the retainer material 56 that extends in an annular shape is once bent over the entire region so as to be straight in the thickness direction, with the groove 79 as a starting point. That is, the angle B ₂ between the surface 75 located on the inner diameter side of the outer diameter region bent portion 74 and the upper surface 76 of the fourth disc unit 64 is approximately at right angles. Although the method of bending at a right angle is not particularly limited, for example, it is performed as follows. As shown in FIG. 11, a region excluding the region on the outer diameter side of the fourth disc portion 64 in the cage material 56 is sandwiched and held in the vertical direction by the holding members 101 and 102, and the fourth disc portion 64 is held. The pressing member 103 is disposed under the outer diameter side region. Next, as shown in FIG. 12, by pushing up the pressing member 103, the outer diameter side region bent portion 74 can be bent at a right angle with respect to the fourth disc portion 64.

  Then, as shown in FIG. 13 and FIG. 14, the outer diameter region bent portion 74 is bent toward the inner diameter side to form the outer diameter region bent portion 74. By performing this step, as shown in FIGS. 13 and 14, a trace 29 of the annular groove at the bending start point is formed.

The angle of bending (inclination angle), that is, the angle between the surface 75 located on the inner diameter side of the outer diameter region bending portion 74 and the upper surface 76 of the fourth disc portion 64 is shown in FIGS. represented by an angle _{B 3} in 14. Angle _{B 3} corresponds to the angle _{B 1} described above. That is, the angle B ₁ and the angle B ₃ are in the same relationship. Angle _{B 1} and the angle _{B 3} is preferably an acute angle.

  In this case, since the protrusion 70 is provided at the center in the circumferential direction of the pocket 73 in the circumferential positional relationship, the protrusion 70 is formed at an appropriate location. And since the outer diameter area | region bending part 74 is bent in the desired position by the cyclic | annular groove | channel 79, the protrusion part 70 is formed in an appropriate position. Specifically, in the protruding portion 70, the corner portion 77 located on the fourth disc portion 64 side comes into contact with the center of the end surface 16 of the needle roller 13. Finally, a surface pressing process is performed on a region of the protrusion 70 that contacts the end surface 16 of the needle roller 13. Thus, the thrust roller bearing retainer 11 having the configuration shown in FIGS. 1 to 3 is manufactured.

  In addition, a step of bending the retainer material 56 bent toward the inner diameter side so that the outer diameter side end 72 of the retainer material 56 extending in an annular shape is straight in the plate thickness direction, and a step of performing a surface pressing process May be carried out continuously. FIG. 15 is an enlarged cross-sectional view illustrating a state in which the outer diameter region bending step is performed. FIG. 16 is an enlarged cross-sectional view illustrating a state in which the surface pressing process is performed. FIG. 17 is an enlarged cross-sectional view showing the distal end of the outer diameter region bent portion after performing the surface pressing process.

  Specifically, as shown in FIG. 15, in the cage material 56 that is bent so that the outer diameter side region bent portion 74 is perpendicular to the fourth disc portion 64, the outer diameter side region bent portion. A region on the inner diameter side than 74 is sandwiched and held by the molds 104 and 105 in the vertical direction. At this time, the outer diameter side edge of the upper mold 104 is positioned closer to the inner diameter side than the outer diameter side edge of the lower mold 105. Further, the mold 106 that pressurizes the outer diameter region bent portion 74 from the upper side to the lower side is disposed so as to be in contact with the surface 78 located on the outer diameter side of the outer diameter region bent portion 74. The mold 106 is abutted with the upper mold 104 and extends in the vertical direction on the inner diameter side end face 106 a, the horizontal surface 106 b that is continuous with the inner diameter side end face 106 a and extends on the outer diameter side, and the outer diameter area bending portion 74. A portion 106d that has an inner diameter side surface 106c that abuts the outer diameter side surface 78 and extends in the vertical direction has a round (R) shape. In this state, when the mold 106 is moved downward so that the inner diameter side end face 106a is along the outer diameter side end face 104a of the mold 104, the outer diameter area bent portion 74 is guided to the inner diameter side by being guided by the round portion 106d. It can be bent so as to be inclined toward the. Thereby, as shown in FIG. 16, the annular groove 79 becomes a trace 29 which is a compression trace by pressing.

  Thereafter, as shown in FIG. 16, the mold 104 is moved further downward, the outer diameter side end face 104 a of the mold 104 is smoothed at the corner located on the inner diameter side in the outer diameter region bent portion 74, and the mold 106 is moved. In the horizontal plane 106b, the corner located on the outer diameter side in the outer diameter region bent portion 74 is smoothed. Thereby, as shown in FIG. 17, the protrusion part 70 by which the area | region which contacts the roller end surface is surface-pressed can be formed.

  As described above, according to the thrust roller bearing retainer 11 and the manufacturing method thereof according to the present embodiment, the annular groove 79 is formed outside the pocket 73 in the groove forming step (step S6), and the outer diameter is increased. In the region bending step (step S7), the outer diameter region bent portion 74 is formed by bending the groove 79 toward the inner diameter side with the bending start point. For this reason, since the annular groove 79 is the folding position, the folding position can be controlled. Moreover, even if the fold portion to be bent is small, the outer diameter side region can be easily bent by the annular groove 79. Therefore, since the contact portion with the center of the roller can be accurately positioned in the protrusion provided at the tip of the outer diameter region bent portion, the rotational torque can be reduced. In addition, the trace of the cyclic | annular groove | channel 79 remains in such a holder | retainer 11. FIG.

  Here, in the above embodiment, the corner portion located on the fourth disc portion side of the projecting portion is in contact with the center of the end face of the needle roller housed in the pocket. It is good also as the following structures. FIG. 18 is a cross-sectional view showing a part of the cage in this case. FIG. 18 corresponds to a cross section of the cage shown in FIG.

  Referring to FIG. 18, a thrust roller bearing retainer 81 according to another embodiment of the present invention is provided with a protruding portion 83 at a position where a pocket 85 is formed in an outer diameter region bent portion 82. ing. The protruding portion 83 is configured to come into contact with the center of the end surface 16 of the needle roller 13 accommodated in the pocket 85 at a corner portion 84 opposite to the fourth disc portion 86 side. The corner portion 84 is subjected to surface pressing. In order to obtain such a configuration, it is preferable to perform processing using a jig having an angle along the corner 84 in the outer diameter region bending step. Also in the cage 81 shown in FIG. 18, the trace 89 of the annular groove that is the bending start point of the outer diameter region bending portion 82 remains.

  The position where the pilot hole is provided may be a position where the pocket is provided. That is, one of the plurality of pockets may be used as a pilot hole. FIG. 19 is a diagram showing a part of the cage in this case. Referring to FIG. 19, a thrust roller bearing retainer 91 according to still another embodiment of the present invention includes a plurality of pockets 92 and a pillar portion 93 positioned between two adjacent pockets 92. A pilot hole 95 is provided between the pocket 92 and the pocket 92 at the position of the column portion 94 where the pocket 92 is to be formed. The pilot holes 95 have a so-called alternative shape in which one of the plurality of pockets 92 provided at equal intervals in the circumferential direction is replaced with the pilot hole 95.

  In the above embodiment, the pilot hole is configured to penetrate straight in the thickness direction. However, the present invention is not limited to this. For example, the pilot hole penetrates so that the wall surface of the pilot hole is tapered. You may do it. In addition, a rectangular hole, a triangular hole, or the like can be employed regardless of the round hole shape. Although the pilot hole is provided as the engaging portion, the present invention is not limited to this, and the engaging portion may be configured by another configuration, for example, a notch.

  In the above embodiment, the drawing process is performed in the uneven shape forming step. However, the present invention is not limited to this, and the uneven shape may be formed by a process other than the drawing process, for example, a bending process.

  In the above embodiment, the cage is configured to form a concavo-convex shape in the plate thickness direction. However, the present invention is not limited to this, and the cage does not have a concavo-convex shape in the plate thickness direction. You may comprise so that the holder | retainer of the shape of a 2 sheet board may be used.

  Further, in the above embodiment, the thrust roller bearing provided with such a cage may be configured not to include a race ring. Furthermore, you may decide to use rollers other than a needle roller, for example, a rod-shaped roller.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above-described embodiment but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

  The thrust roller bearing retainer and the manufacturing method thereof according to the present invention are required in the case where a thrust roller bearing retainer having good performance and a more efficient production of such a thrust roller bearing retainer are required. , Effectively used.

  11, 81, 91 Cage, 12 Rotating axis, 13 Roller, 14, 15 Race ring, 16, 17 End face, 18, 19 Race surface, 20 Thrust roller bearing, 21, 73, 85, 92 Pocket, 22, 57 Through Hole, 23, 24 Annular part, 25, 93, 94 Pillar part, 26, 27, 28 Rolling stopper part, 29, 89 Trace, 31, 32, 33, 34, 61, 62, 63, 64, 86 Disc part 36, 37, 38, 39, 66, 67, 68, 69 Cylindrical part, 41, 74, 82 Bending part of outer diameter region, 42, 43, 75, 76, 78 surface, 44, 70, 83 Protruding part, 45 , 77, 84 Corner, 51, 52, 71, 95 Pilot hole, 56 Cage material, 72 End, 79 Groove, 101, 102 Holding member, 103 Press member, 104, 105, 106 Mold, 104a Diameter side end face, 106a inner diameter side end face, 106b horizontal, 106c inner diameter side, 106d moiety.

Claims (4)

A thrust roller bearing retainer provided in a thrust roller bearing and provided with a plurality of pockets for accommodating rollers,
An outer diameter region bent portion formed by bending an annular groove provided on the outer diameter side from the pocket as a folding start point on the inner diameter side;
It is provided at the tip of the outer diameter region bent portion at a position aligned with each of the pockets, and protrudes from the edge on the outer diameter side of the pocket toward the inner diameter side so as to contact the end face of the roller accommodated in the pocket. With protrusions,
A cage for a thrust roller bearing, in which the trace of the groove remains at the bending starting point.   2. The thrust roller bearing retainer according to claim 1, wherein a region of the protruding portion that comes into contact with the end surface of the roller is subjected to surface pressing. A method of manufacturing a thrust roller bearing retainer provided in a thrust roller bearing and provided with a plurality of pockets for accommodating rollers,
A step of preparing a cage material to be a cage;
A step of forming an outer shape of the cage material having a portion that becomes a protruding portion that protrudes toward an inner diameter side from an outer edge side edge of the pocket so as to contact an end surface of a roller accommodated in the pocket. When,
Forming the pocket with respect to the cage material;
For the cage material, a step of forming an annular groove on the outer diameter side of the pocket;
And a step of bending an area of the retainer material that is located on the outer diameter side of the pocket toward the inner diameter side to form an outer diameter area bent portion. Production method.   The manufacturing method of the cage | basket of the thrust roller bearing of Claim 3 further equipped with the process of performing a surface pressing process to the area | region which contacts the end surface of the said roller among the said protrusion parts.

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