JP2016114154A - Thrust roller bearing cage and process of manufacture the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thrust roller bearing cage of which strength is improved and lubricant oil flow is made superior and a process of manufacture the same.SOLUTION: A thrust roller bearing cage [11] of this invention is installed at a thrust roller bearing [20] and provided with a plurality of pockets [21] for storing rollers [13]. There are provided an outer diameter area bent part [41] formed by bending an area positioned at an outer diameter side rather than the pockets [21] toward its inner diameter side and a protrusion part [44] arranged at the extremity end of the outer diameter area bent part [41] at a position where it is arranged in row of each of the pockets [21] and protruded from an outer diameter side of each of the pockets [21] toward an inner diameter side so as to be contacted with an end surface [16] of each of the rollers [13] stored in the pockets [21], and a width of the protrusion part [44] is equal to or more than 1/3 and equal to or less than 2/3 of a width of each of the pockets [21].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. According to this thrust roller bearing retainer, it is disclosed that the rotational torque of the roller can be kept small because the tip of the convex portion contacts the vicinity of the rotation center of the roller.

Japanese Patent Laid-Open No. 10-220482

  However, the thrust roller bearing of Patent Document 1 has a case where the strength is not sufficient and / or the flow of the lubricating oil is not good.

  Therefore, an object of the present invention is to provide a thrust roller bearing retainer that improves strength and improves the flow of lubricating oil, and a method for manufacturing the same.

  The present inventors have found that the problem that the strength is insufficient and the problem that the flow of lubricating oil is not good in the thrust roller bearing of Patent Document 1 is caused by the shape of the convex portion. Then, as a result of intensive studies conducted by the inventor to improve the strength and improve the flow of the lubricating oil, the inventors have determined that the width of the convex portion is specified within a predetermined range.

  That is, the cage of the thrust roller bearing of the present invention is a cage of a thrust roller bearing provided in the thrust roller bearing and provided with a plurality of pockets for accommodating the rollers, and is located on the outer diameter side of the pocket. An outer diameter area bent portion formed by bending the area to the inner diameter side, and a pocket provided at the tip of the outer diameter area bent portion at a position aligned with the pocket so as to contact the end face of the roller accommodated in the pocket A protrusion protruding from the edge on the outer diameter side toward the inner diameter side, and the width of the protrusion is not less than 1/3 and not more than 2/3 of the width of the pocket.

  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 the retainer serves as a cage. The outer shape including the step of preparing the container material and the part that becomes the protruding part protruding from the edge on the outer diameter side of the pocket to the inner diameter side so as to contact the end surface of the roller accommodated in the pocket with respect to the cage material A step of forming a shape, a step of forming a pocket with respect to the cage material, and a region located on the outer diameter side of the pocket in the cage material is folded toward the inner diameter side to form an outer diameter region bent portion. In the step of forming the outer shape, the outer shape including a portion to be a protrusion having a width of 1/3 or more and 2/3 or less of the width of the pocket is formed.

  According to the thrust roller bearing retainer and the manufacturing method thereof of the present invention, since the width of the protruding portion is 1/3 or more of the width of the pocket, the strength of the protruding portion can be improved. Further, since the width of the protruding portion is 2/3 or less of the width of the pocket, the space formed in the state where the end face of the roller and the protruding portion are in contact with each other is sufficient in the pocket, so that the lubricating oil flows into the space. Therefore, the flow of the lubricating oil can be improved. Therefore, the thrust roller bearing retainer and the manufacturing method thereof according to the present invention can improve the strength and improve the flow of the lubricating oil.

  Preferably, in the cage of the thrust roller bearing of the present invention, the protrusion is an arc in plan view, and the radius of the arc of the protrusion is not less than 0.4 mm and not more than 0.7 mm.

  Preferably, in the method for manufacturing the cage of the thrust roller bearing of the present invention, in the step of forming the outer shape, the outer shape including a portion that becomes a projecting portion that is an arc having a radius of 0.4 mm or more and 0.7 mm or less in plan view. Form.

  When the protruding portion is an arc, the shape of the protruding portion can be prevented from being deformed when the region located on the outer diameter side of the pocket is bent in order to form the outer diameter region bent portion. When the radius of the arc of the protrusion is 0.4 mm or more, deformation of the protrusion when bent can be further prevented, and the strength of the protrusion can be improved. If the radius of the arc of the protruding portion is 0.7 mm or less, the area of the portion of the protruding portion that contacts the roller even if the portion of the protruding portion that contacts the roller wears out using the cage of the thrust roller bearing Increase is small. For this reason, even if the cage of the thrust roller bearing is used for a long period of time, the reduction of the rotational torque can be maintained.

  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.

  Preferably, in the cage of the thrust roller bearing of the present invention, the protruding portion is formed so as to bend the region on the outer diameter side of the cage obliquely to the inner diameter side.

  In the method for manufacturing the cage of the thrust roller bearing according to the present invention, preferably, in the step of forming the outer diameter region bent portion, a region of the cage material located on the outer diameter side from the pocket is bent obliquely toward the inner diameter side.

  Since the outer diameter region bent portion is formed by obliquely bending the region located on the outer diameter side of the pocket toward the inner diameter side, it is not inclined as in Patent Document 1 (inclination angle is 0 °). In comparison with the above, the area in contact with the roller is small in the protrusion provided at the tip of the outer diameter region bent portion. When the roller is urged toward the outer diameter side from the shaft center by the rotational centrifugal force of the roller, the portion that contacts the roller in the protrusion becomes friction, but contacts the roller in the obliquely bent protrusion Since the area is small, the rotational resistance can be reduced. For this reason, rotational torque can be reduced.

  According to the cage and the manufacturing method of the thrust roller bearing of the present invention, the strength can be improved and the flow of the lubricating oil can be improved.

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. FIG. 3 is an enlarged plan view showing a part of a cage of the thrust roller bearing shown in FIG. 2. 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 shows a case where the cross section is taken along line 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. 4 is an enlarged plan view showing a part of the cage 11 of the thrust roller bearing shown in FIGS. 1 and 2, and is an enlarged plan view of a region indicated by IV in FIG. From the viewpoint of easy understanding, FIG. 4 shows a needle roller 13 accommodated in a pocket 21 described later. 1 and FIG. 4 and the vertical direction of the paper in FIGS. 2 and 3 are the rotation axis direction of the cage 11. 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. 1-4, the structure of the retainer 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.

  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 roller 13 is accommodated so as to be pushed into the pocket 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. That is, the retainer 11 is provided with an outer diameter region bent portion 41 formed by bending an area located on the outer diameter side of the pocket 21 toward the 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.

  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 projecting portion 44) that is the portion located on the innermost diameter side of the projecting portion 44 is accommodated in 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 shape of the protrusion 44 will be described with reference to FIG. As shown in FIG. 4, the width L of the protrusion 44 is not less than 1/3 and not more than 2/3 of the width X of the pocket 21. The width X of the pocket 21 is the length in the circumferential direction, and is the width of the space in which the roller stoppers 26 to 28 are not formed. The width L of the protruding portion 44 is the width of the maximum width position of the protruding portion 44, and is the width of the root portion of the protruding portion 44 in FIG. 4. When the protrusion 44 is a circular arc in plan view, the width L of the protrusion 44 is a distance connecting both ends of the protrusion 44, that is, a string. When the protrusion 44 is an arc in plan view, the radius R of the arc of the protrusion 44 is not less than 0.4 mm and not more than 0.7 mm, and preferably not less than 0.5 mm and not more than 0.6 mm. The radius R is the radius of the circle when the protrusion 44 is a part of the circle in plan view.

  As shown in FIGS. 1 and 2, 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. 5 is a flowchart showing representative steps of a method of manufacturing the thrust roller bearing retainer 11 according to the embodiment of the present invention.

  Referring to FIG. 5, 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. 6 is a cross-sectional view of the cage material after performing the uneven shape forming step. The cross section shown in FIG. 6 corresponds to the cross section shown in FIG. Specifically, referring to FIG. 6, the flat retainer material 56 is subjected to drawing to provide first to fourth disc portions 61 to 64 and first to fourth cylindrical portions. 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. 7 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. 7 corresponds to a portion shown in a region VII 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). In this step, an outer shape including a portion that becomes a protrusion having a width of 1/3 or more and 2/3 or less of the width of the pocket formed in the pocket forming step (step S5) to be performed later is formed. In addition, an outer shape including a projecting portion that is an arc having a radius of 0.4 mm or more and 0.7 mm or less, preferably 0.5 mm or more and 0.6 mm or less in plan view is formed.

  FIG. 8 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. 8 corresponds to the portion shown in the region VII in FIG. 2, and is a case where the cross section is shown by VIII-VIII in FIG. Specifically, the retainer material 56 is formed by punching straight in the thickness direction so as to obtain the final outer shape of the retainer 11 by the outer diameter region bending step (step S7) to be performed later. To do. 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. 9 is a view showing a part of the cage material 56 after the pocket forming step performed after the outer shape forming step. FIG. 9 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. 10 is an enlarged cross-sectional view showing a part of the cage material after performing the pocket forming step. The cross section shown in FIG. 10 corresponds to the portion shown in the region III in FIG. 2, and is a case where the cross section is shown by XX 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. 10, 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 formed projecting portion 70 and the formed pocket 73, the projecting portion 70 can be formed accurately and efficiently, and the projecting portion 44 is accurately formed at an appropriate location. Therefore, 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. 9 and 10, 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), in the outer diameter region bending step (step S7), which will be described later, a groove 79 is formed at a position serving as a bending start point in order to form the outer diameter region bent portion 41. By performing the groove forming step (step S6), the outer diameter side region of the cage material 56 can be easily bent inward in the outer diameter region bending step (step S7) described later. (Step S6) may be omitted. Further, the order of steps S4 to S6 is not particularly limited.

  Next, 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, it is preferable to bend the inner diameter side obliquely at an acute inclination angle to form the outer diameter region bent portion. In addition, when the groove forming step (step S6) is performed, the outer diameter side bent portion is formed by bending the outer diameter side region of the cage material 56 using the groove 79 as a bending start point.

FIG. 11 is an enlarged cross-sectional view showing a part of the cage material in an intermediate stage of the outer diameter region bending process. 12 and 13 are enlarged sectional views showing a state in which the outer diameter region bending step is performed. 14 and 15 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. 11 and 14 corresponds to a portion shown in a region VII in FIG. The cross section shown in FIG. 15 corresponds to the portion shown in region III in FIG. The cross section shown in FIGS. 12 and 13 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 VII in FIG. Show. Here, as shown in FIG. 11, the end 72 on the outer diameter side of the annularly extending cage material 56 is once bent over the entire region so as to be straight in the thickness direction. 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. 12, in the cage material 56, the region excluding the region on the outer diameter side of the fourth disc portion 64 is sandwiched and held by the holding members 101 and 102 in the vertical direction, and the fourth disc portion 64 is retained. The pressing member 103 is disposed under the outer diameter side region. Next, as shown in FIG. 13, 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. 14 and FIG. 15, the outer diameter region bent portion 74 is bent toward the inner diameter side to form the outer diameter region bent portion 74. 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 15. 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. 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. Further, as shown in FIG. 4, the width L of the protrusion is 1/3 or more and 2/3 or less of the width of the pocket, and preferably the radius R of the arc of the protrusion is 0.4 mm or more and 0.7 mm or less. A certain protrusion 70 is formed. 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 4 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. 16 is an enlarged cross-sectional view illustrating a state in which the outer diameter region bending step is performed. FIG. 17 is an enlarged cross-sectional view illustrating a state in which the surface pressing process is performed. FIG. 18 is an enlarged cross-sectional view showing an enlarged front end of the outer diameter region bent portion after performing the surface pressing process. Specifically, as shown in FIG. 16, 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. Thereafter, as shown in FIG. 17, the mold 104 is further moved downward, the outer diameter side end face 104a of the mold 104 is smoothed at the corner located on the inner diameter side at the outer diameter region bent portion 74, and the mold 106 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. 18, the protrusion part 70 by which the area | region which contacts the roller end surface is surface-pressed can be formed.

  In the above embodiment, the corner portion located on the fourth disc portion side of the protruding portion is in contact with the center of the end surface of the needle roller housed in the pocket. It is good also as a structure of. FIG. 19 is a cross-sectional view showing a part of the cage in this case. FIG. 19 corresponds to a cross section of the cage shown in FIG.

  Referring to FIG. 19, 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.

  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. 20 is a diagram showing a part of the cage in this case. Referring to FIG. 20, 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.

  Next, the effect of the thrust roller bearing retainer and the manufacturing method thereof according to the present embodiment will be described. The inventor has obtained the knowledge described in Table 1 below regarding the state and strength of the lubricating oil flow with respect to the width of the protrusion.

  In Table 1, “width L” means the width L of the protrusion 44 shown in FIG. 4 and is a ratio to the width X of the pocket 21.

  Further, the “lubricating oil flow” is a lubricating oil flow when using a thrust roller bearing in which a roller is accommodated in a cage pocket. “◎” means that the flow of the lubricating oil is very good. “◯” means that the flow of the lubricating oil is good. “Δ” means that the flow of the lubricating oil is not good. “X” means that the lubricating oil flow is poor. That is, ◎, ○, Δ, × in order of good lubricant flow.

  Further, the “strength” is the strength of the protrusion when using a thrust roller bearing in which rollers are accommodated in the cage pockets. “O” means that the protrusion can be maintained by using a thrust roller bearing. “X” means that the protrusion cannot be maintained by using a thrust roller bearing. That is, it is (circle) and x in order with high intensity | strength.

  As shown in Table 1, in Examples 1 to 3, in which the width of the protruding portion is 1/3 or more and 2/3 or less of the width of the pocket, the outer diameter side end surface of the roller and the protruding portion are in contact with each other. In this case, a sufficient gap is formed between the roller, the outer-diameter region bent portion, and the protruding portion, so that the lubricating oil can flow through the gap, so that the lubricating oil easily flows in the thrust roller bearing. Specifically, in Examples 1 to 3 in which the width L of the protrusion is 1/3 or more and 2/3 or less of the width X of the pocket, the region from the outer diameter side of the pocket is directed upward (in the axial direction). When the lubricating oil flows, it is difficult for the lubricating oil to be prevented from flowing by the protrusion located at the center. For this reason, since the lubricating oil flows upward from the outer diameter side region of the pocket and can flow in the circumferential direction, the flow of the lubricating oil is good. On the other hand, in Comparative Example 2 in which the width L of the protruding portion is 3/4 of the pocket width X, the protruding portion becomes an obstacle when the lubricating oil flows upward from the region on the outer diameter side of the pocket. Oil flow is not good. In Comparative Example 1 in which the width L of the protrusion is the same as the width X of the pocket, the lubricant does not flow upward from the region on the outer diameter side of the pocket due to the protrusion.

  In addition, as shown in Table 1, Examples 1 to 3 in which the width L of the projecting portion is 1/3 or more and 2/3 or less of the pocket width X are the rotational centrifugal force (from the inner diameter side to the outer diameter side). When the projecting force is applied to the projecting portion, it is easy to withstand the load from the roller and maintain its shape, and the strength is high. On the other hand, in Comparative Example 3 in which the width L of the protruding portion is 1/4 of the width X of the pocket, the shape is easily deformed and the strength is low with respect to the load from the rollers.

  Therefore, the thrust roller bearing retainer and the manufacturing method thereof according to the present embodiment improve the strength and improve the lubricating oil since the width L of the protrusion is 1/3 or more and 2/3 or less of the pocket width X. Flow can be improved.

  In addition, the protrusion is formed so that the outer diameter side region of the cage is bent obliquely to the inner diameter side, and the region of the protrusion that contacts the roller end face is subjected to surface pressing. In this case, the width L of the protruding portion is set to 1/3 or more and 2/3 or less of the width X of the pocket, thereby further providing the following effects. When the outer diameter region bent portion is formed by bending a region located on the outer diameter side of the pocket so as to have an inclination angle on the inner diameter side, the inclination angle is 0 ° as in Patent Document 1 (comparative example) Compared with the case of 1), the area in contact with the roller at the protruding portion is small. Specifically, in Patent Document 1 with an inclination angle of 0 °, the entire tip end surface of the convex portion comes into contact with the center of the end surface of the roller accommodated in the pocket. The corner located closest to the inner diameter side on the tip surface is in contact with the center of the end surface of the roller accommodated in the pocket, and is in a state close to point contact rather than surface contact. When the roller is urged from the shaft center toward the outer diameter side by the rotational centrifugal force of the roller, the portion of the protrusion that contacts the roller becomes friction, so the area of contact with the roller is small. Since the protrusion can reduce the rotational resistance, the rotational torque can be reduced. In order to form such a protruding portion, the outer diameter region bending step (step S7) and the surface pressing step are performed, but the width L of the protruding portion is set to 1/3 or more of the width X of the pocket. Thus, during these steps, the shape of the protruding portion is hardly damaged, and the shape can be prevented from collapsing. Specifically, in the outer diameter region bending process (step S7) and the surface pressing process, for example, the press process is performed as described above, and the protrusion can be prevented from being deformed and crushed during the press process. .

  In addition, the inventor has found the knowledge described in Table 2 below regarding the rotational torque after long-term use, the shape during processing, and the strength with respect to the radius of the arc of the protrusion when the protrusion is an arc in plan view. Have gained. In addition, as for the protrusion part of Table 2, the width | variety of a protrusion part is 1/2 of the width | variety of a pocket.

  In Table 2, “radius R” means that the protrusion is a circular arc in plan view, and means the radius of the arc, and is the radius R of the protrusion 44 shown in FIG. 4.

  Further, “torque after a long time” is a rotational torque when a thrust roller bearing in which a roller is accommodated in a cage pocket is used for a long time. “◯” means that the rotational torque after long-time use has not substantially decreased from the initial rotational torque. “X” means that the rotational torque after long-time use is greatly reduced from the initial rotational torque. That is, it is (circle) and x in order with a small fall of the rotational torque after long-time use.

  The “shape at the time of processing” is the shape of the protruding portion after the outer diameter region bending step (step S7). “◯” means that the shape of the protrusion is maintained even when the outer diameter region bending step is performed. “X” means that the shape of the protruding portion is broken when the outer diameter region bending step is performed.

  The “strength” is the same as the strength in Table 1. “O” means that the protrusion can be maintained by using a thrust roller bearing. “Δ” means that the protrusion can be maintained if the load from the roller is moderate or less by using the thrust roller bearing, and the strength is higher than “x” in Table 1. That is, in Table 1 and Table 2, it is (circle), (triangle | delta), and x in order with a high intensity | strength.

  As shown in Table 2, in Examples 2, 4 to 7 in which the radius R of the arc of the protrusion is 0.3 mm or more and 0.7 mm or less, the thrust roller bearing is used for a long time, and the roller contacts the roller at the protrusion. Even if the portion is worn, the increase in the area of the portion in contact with the roller in the protruding portion (the contact area with the roller in the protruding portion after wear) is small, so that reduction in rotational torque can be suppressed. That is, when the protrusion is worn by using the cage for a long time, the area in contact with the roller increases. However, since the rate of increase is low, a decrease in rotational torque after long-term use can be suppressed.

  In Examples 2 and 5 to 8, in which the radius R of the arc of the protrusion is 0.4 mm or more and 0.8 mm or less, the shape of the protrusion does not change when the outer diameter region bending step (step S7) is performed. . In Examples 2 and 5 to 8 in which the radius R of the arc of the protrusion is 0.4 mm or more and 0.8 mm or less, the outer diameter region bending step (step S7) and surface pressing shown in FIGS. Can be effectively suppressed in the shape of the protruding portion.

  Further, if the width of the protruding portion is 1/3 or more and 2/3 or less of the width of the pocket, the protruding portion is not subject to a load from a medium or larger roller regardless of the radius R of the arc of the protruding portion. In Examples 2 and 5 to 8, which have the strength to withstand, but the radius R of the arc of the protrusion is 0.4 mm or more and 0.8 mm or less, the strength is further increased.

  Therefore, in Examples 2 and 5 to 7 in which the radius R of the arc of the protruding portion is 0.4 mm or more and 0.7 mm or less, the torque after a long time, the shape maintenance at the time of processing, and the evaluation of strength are all “good”. That is, the width of the protruding portion is 1/3 or more and 2/3 or less of the width of the pocket, and the radius of the arc of the protruding portion is 0.4 mm or more and 0.7 mm or less, so that the strength is improved. The flow can be improved, the decrease in rotational torque after long-term use can be suppressed, and the shape during processing can be maintained.

  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 Roller stopper part, 31, 32, 33, 34, 61, 62, 63, 64, 86 Disc part, 36, 37, 38, 39, 66, 67, 68, 69 Cylindrical part, 41, 74, 82 Outer diameter region bent part, 42, 43, 75, 76, 78 face, 44, 70, 83 Protruding part, 45, 77, 84 angle 51, 52, 71, 95 Pilot hole, 56 Cage material, 72 End, 79 Groove, 101, 102 Holding member, 103 Pressing member, 104, 105, 106 Mold, 104a Outer diameter side end face, 106 a inner diameter side end face, 106b horizontal plane, 106c inner diameter side face, 106d portion.

Claims (8)

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 area located on the outer diameter side of the pocket toward 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,
The thrust roller bearing retainer has a width of the protrusion that is not less than 1/3 and not more than 2/3 of the width of the pocket. The protrusion is an arc in plan view,
The thrust roller bearing retainer according to claim 1, wherein a radius of the arc of the protruding portion is 0.4 mm or more and 0.7 mm or less.   The thrust roller bearing retainer according to claim 1 or 2, wherein a region of the protruding portion that contacts the end surface of the roller is subjected to surface pressing.   The thrust roller bearing retainer according to any one of claims 1 to 3, wherein the protrusion is formed so that an outer diameter side region of the retainer is obliquely bent toward an inner diameter side. 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 including a portion that becomes a protruding portion that protrudes toward the inner diameter side from an outer edge on the outer diameter side of the pocket so as to contact an end surface of the roller accommodated in the pocket. When,
Forming the pocket with respect to the cage material;
Bending the region located on the outer diameter side of the pocket in the cage material to the inner diameter side, and forming an outer diameter region bent portion,
A method of manufacturing a retainer for a thrust roller bearing, wherein in the step of forming the outer shape, an outer shape including a portion serving as the protruding portion having a width of 1/3 or more and 2/3 or less of the width of the pocket is formed.   6. The thrust roller bearing according to claim 5, wherein in the step of forming the outer shape, the outer shape including a portion serving as the protruding portion which is an arc having a radius of 0.4 mm or more and 0.7 mm or less in plan view is formed. A method for manufacturing a cage.   The method of manufacturing a cage for a thrust roller bearing according to claim 5 or 6, further comprising a step of performing a surface pressing process on a region of the protruding portion that contacts the end surface of the roller.   The thrust according to any one of claims 5 to 7, wherein in the step of forming the outer diameter region bent portion, a region of the retainer material located on the outer diameter side of the pocket is obliquely bent toward the inner diameter side. A method for manufacturing a roller bearing cage.

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