Manufacturing method for bearing ring members

Abstract

To provide a method for manufacturing a bearing ring member, which can reduce mold cost and improve a yield.SOLUTION: This method for manufacturing a bearing ring member comprises: a first inversion step of holding a first workpiece member 10 having a first annular body part 11 including a first surface 11a which becomes an orbital plane 31a between a punch 60 and a die 70 in an axial direction to form an inner ring member 30; and a second inversion step of holding a second workpiece member having a second annular body part including a second surface which becomes an orbital plane between the punch 60 and the die 70 in the axial direction to form an outer ring member. In the first inversion step, the first workpiece member 10 is held between the punch 60 and the die 70 in a state where the first surface 11a faces a first side S1 in the axial direction. In the second inversion step, the second workpiece member is held between the punch 60 and the die 70 in a state where the second surface faces a second side S2 opposite the first side S1.SELECTED DRAWING: Figure 4

Description

Technical Field

[0004] , , , , , ,

[0005]

[0001] The present invention relates to a method for manufacturing a ring member for a shaft.

Background Art

[0002] Patent Document 1 describes a method for manufacturing an inner ring and an outer ring of a bearing from one material by forming the material into a predetermined shape using a mold and then cutting and separating it into two members. Hereinafter, such a forming method is also referred to as parent-child forming. Patent Documents 2 and 3 also describe methods for manufacturing an inner ring and an outer ring of a bearing by parent-child forming.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the manufacturing method as described above, since the inner ring and the outer ring can be manufactured by one mold, the cost of the mold can be reduced. On the other hand, in the manufacturing method as described above, the same number of inner rings and outer rings are formed. Therefore, if the defect rates between the inner ring and the outer ring are different, either the inner ring or the outer ring will be insufficient. However, in parent-child forming, only one of the inner ring or the outer ring cannot be formed. Usually, the defect rates of the inner ring and the outer ring do not match. Therefore, for example, one of the surplus inner rings or outer rings will be discarded, and there is a risk that the yield will decrease.

[0005] Therefore, the present invention aims to provide a method for manufacturing a bearing ring member that can reduce mold costs and improve yield. [Means for solving the problem]

[0006] The present invention provides a method for manufacturing a bearing ring member, comprising: a first inversion step of forming an inner ring member by axially clamping a first workpiece member having an annular first body portion including a first surface that serves as a raceway surface between a punch and a die so that the first surface faces radially outward; and a second inversion step of forming an outer ring member by axially clamping a second workpiece member having an annular second body portion including a second surface that serves as a raceway surface between a punch and a die so that the second surface faces radially inward. In the first inversion step, the first workpiece member is clamped between the punch and a die with the first surface facing the first side in the axial direction, and in the second inversion step, the second workpiece member is clamped between the punch and a die with the second surface facing the second side opposite to the first side.

[0007] In this method for manufacturing bearing ring members, a common punch and die are used in the first and second inversion steps. In the first inversion step, the inner ring member is formed by sandwiching the first workpiece member between the punch and die with the first surface facing the first side in the axial direction. In the second inversion step, the outer ring member is formed by sandwiching the second workpiece member between the punch and die with the second surface facing the second side opposite to the first side. This allows the inner and outer ring members to be formed using a common punch and die, thereby reducing mold costs. Furthermore, for example, if there is a shortage of either the inner or outer ring member, the first or second inversion step can be performed so that the number of inner and outer ring members becomes equal. As a result, the excess of inner or outer ring members can be suppressed, and the yield can be improved. Therefore, this method for manufacturing bearing ring members can reduce mold costs and improve yield.

[0008] In the first reversal step, the first workpiece may be pressed radially toward the punch by a pressing member, while the first workpiece is clamped between the punch and the die. In the second reversal step, the second workpiece may be pressed radially toward the punch by a pressing member, while the second workpiece is clamped between the punch and the die. In this case, the first or second workpiece can be well clamped between the punch and the die.

[0009] The present invention provides a method for manufacturing a bearing ring member, comprising the steps of: preparing a first workpiece member having an annular first body portion including a first surface that serves as a raceway surface, and a second workpiece member having an annular second body portion including a second surface that serves as a raceway surface; and inversion steps of forming an inner ring member and an outer ring member by axially clamping the first workpiece member and the second workpiece member, which are stacked so that the first surface faces the first side in the axial direction and the second surface faces the second side opposite to the first side, with a punch and a die, so that the first surface faces the radially outward direction and the second surface faces the radially inward direction.

[0010] In this method for manufacturing bearing ring members, an inner ring member and an outer ring member are formed by sandwiching a stacked first workpiece member and a second workpiece member between a punch and a die. This allows for the formation of both the inner ring member and the outer ring member using a common punch and die, thereby reducing mold costs. Furthermore, for example, if there is a shortage of either the inner ring member or the outer ring member, the first or second workpiece member can be sandwiched between the punch and die to form the inner ring member or the outer ring member so that the number of inner ring members and outer ring members are equal. As a result, excess inner ring members or outer ring members can be suppressed, and yield can be improved. Therefore, this method for manufacturing bearing ring members can reduce mold costs and improve yield.

[0011] In the inversion process, the first workpiece or the second workpiece may be pressed radially toward the punch by a pressing member, while the first workpiece and the second workpiece are sandwiched between the punch and the die. In this case, the first workpiece and the second workpiece can be well sandwiched between the punch and the die.

[0012] The first workpiece member and the second workpiece member may have the same shape as each other. In this case, an inner ring member and an outer ring member can be formed that have shapes that are symmetrical with respect to the radial direction.

[0013] The first workpiece member and the second workpiece member may have different shapes from each other. In this case, an inner ring member and an outer ring member can be formed that have shapes asymmetrical with respect to the radial direction.

[0014] The punch has a cylindrical punch body, and the die has a cylindrical or columnar die body that sandwiches at least one of the first workpiece member and the second workpiece member between itself and the punch body, and formulas (1) and (2) may be satisfied. D1-2×A=d1…(1) D² + 2 × A = d² ... (2) In equations (1) and (2), D1 is the outer diameter of the die body, d1 is the inner diameter of the first workpiece, D2 is the inner diameter of the punch body, and d2 is the outer diameter of the second workpiece. In this case, the first workpiece and the second workpiece can be securely sandwiched between the punch and the die.

[0015] The present invention's method for manufacturing bearing ring members may further include the steps of: acquiring information regarding the difference between the number of inner ring members formed by a first inversion step and the number of outer ring members formed by a second inversion step; and, if a difference exists, performing the first inversion step or the second inversion step so that the number of inner ring members and the number of outer ring members become equal to each other. In this case, it is possible to reliably suppress the excess of inner ring members or outer ring members, and improve the yield.

[0016] The manufacturing method of the ring member for a shaft of the present invention further includes a step of obtaining information regarding the difference between the number of inner ring members formed by the inversion step and the number of outer ring members formed by the inversion step, and when there is a difference, sandwiching the first workpiece member or the second workpiece member between a punch and a die so that the number of inner ring members and the number of outer ring members become equal to each other, and forming an inner ring member or an outer ring member. In this case, it is possible to surely suppress the excess of the inner ring member or the outer ring member, and improve the yield.

[0017] The first workpiece member may have a pair of first flange portions protruding from the first main body portion toward the side of the first surface, and the second workpiece member may have a pair of second flange portions protruding from the second main body portion toward the side of the second surface. According to this manufacturing method of the ring member for a shaft, the inner ring member and the outer ring member can be manufactured from the first workpiece member and the second workpiece member having such a U-shaped cross-sectional shape.

Advantages of the Invention

[0018] According to the present invention, it is possible to provide a manufacturing method of a ring member for a shaft that can reduce the cost of the mold and improve the yield.

Brief Description of the Drawings

[0019] [Figure 1] (a) and (b) are cross-sectional views for explaining the step of forming an inner ring member from the first workpiece member. [Figure 2] (a) and (b) are cross-sectional views for explaining the step of forming an outer ring member from the second workpiece member. [Figure 3] (a) and (b) are cross-sectional views for explaining the burring step. [Figure 4] (a) to (c) are cross-sectional views for explaining the first inversion step. [Figure 5] It is a plan view of the pressing member. [Figure 6] (a) to (c) are cross-sectional views for explaining the second inversion process. [Figure 7] (a) and (b) are cross-sectional views for explaining the first modification example. [Figure 8] It is a cross-sectional view for explaining the second modification example. [Figure 9] (a) to (c) are cross-sectional views for explaining the third modification example. [Figure 10] (a) and (b) are cross-sectional views for explaining other modification examples. [Figure 11] (a) and (b) are cross-sectional views for explaining other modification examples.

Mode for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0021] In the manufacturing method of the ring member for a shaft according to the embodiment, as shown in FIG. 1, the inner ring member 30 is manufactured from the first workpiece member 10. Further, as shown in FIG. 2, the outer ring member 40 is manufactured from the second workpiece member 20. The inner ring member 30 and the outer ring member 40 are substantially cylindrical ring members for a shaft. In FIGS. 1 and 2, cross-sections parallel to the axial direction (the direction parallel to the central axis CL) of the inner ring member 30 and the outer ring member 40 are shown. In this example, each of the first workpiece member 10, the second workpiece member 20, the inner ring member 30, and the outer ring member 40 has a substantially U-shaped cross-sectional shape.

[0022] The inner ring member 30 can be used, for example, as the inner ring of a bearing. The manufactured inner ring member 30 itself may be used as the inner ring, or the inner ring may be manufactured by further processing the inner ring member 30. The outer ring member 40 can be used, for example, as the outer ring of a bearing. The manufactured outer ring member 40 itself may be used as the outer ring, or the outer ring may be manufactured by further processing the outer ring member 40. The bearing to which the inner ring member 30 and the outer ring member 40 are applied may be any type of bearing, such as a needle bearing, cylindrical roller bearing, tapered roller bearing, ball bearing, etc.

[0023] The inner ring member 30 has a main body 31 and a pair of flange portions 32 and 33. The main body 31 is formed in a cylindrical shape and has a cylindrical raceway surface 31a facing radially outward. One flange portion 32 protrudes radially outward from the first axial side S1 (upper side in Figure 1) end of the main body 31, and the other flange portion 33 protrudes radially outward from the second side (opposite side to the first side S1) S2 end of the main body 31. Each flange portion 32 and 33 is formed in a substantially annular plate shape. In this example, each flange portion 32 and 33 curves up from the main body 31, and a curved portion (R portion) is formed between each flange portion 32 and 33 and the main body 31.

[0024] The outer ring member 40 has a main body portion 41 and a pair of flange portions 42 and 43. In this example, the outer ring member 40 has a shape that is radially symmetrical to the inner ring member 30. The main body portion 41 is formed in a cylindrical shape and has a cylindrical raceway surface 41a facing radially inward. One flange portion 42 protrudes radially inward from the end of the first side S1 of the main body portion 41, and the other flange portion 43 protrudes radially inward from the end of the second side S2 of the main body portion 41. Each flange portion 42 and 43 is formed in a substantially annular plate shape. In this example, each flange portion 42 and 43 curves up from the main body portion 41, and a curved portion (R portion) is formed between each flange portion 42 and 43 and the main body portion 41.

[0025] The first workpiece member 10 has a first main body portion 11 and a pair of first flange portions 12 and 13. The first main body portion 11 is formed in the shape of an annular plate and has a first surface 11a which becomes the raceway surface 31a of the inner ring member 30. In this example, the first surface 11a is an annular flat surface. One of the first flange portions 12 protrudes from the radial inner edge of the first main body portion 11 toward the first surface 11a (upper side in Figure 1), and the other first flange portion 13 protrudes from the radial outer edge of the first main body portion 11 toward the first surface 11a. Each of the first flange portions 12 and 13 is formed in a substantially cylindrical shape. In this example, each of the first flange portions 12 and 13 curves upward from the first main body portion 11, and a curved portion (R portion) is formed between each of the first flange portions 12 and 13 and the first main body portion 11.

[0026] The second workpiece member 20 has a second main body portion 21 and a pair of second flange portions 22 and 23. In this example, the second workpiece member 20 has the same shape as the first workpiece member 10. The second main body portion 21 is formed in the same annular plate shape as the first main body portion 11 and has a second surface 21a that becomes the raceway surface 41a of the outer ring member 40. In this example, the second surface 21a is an annular flat surface. One second flange portion 22 protrudes from the radial inner edge of the second main body portion 21 toward the second surface 21a side (upper side in Figure 2), and the other second flange portion 23 protrudes from the radial outer edge of the second main body portion 21 toward the second surface 21a side. Each of the second flange portions 22 and 23 is formed in the same substantially cylindrical shape as the first flange portion 12. In this example, each second flange portion 22, 23 curves upward from the second main body portion 21, and a curved portion (R portion) is formed between each second flange portion 22, 23 and the second main body portion 21.

[0027] The manufacturing method for bearing ring members of this embodiment comprises a first preparation step (Figure 1(a)), a second preparation step (Figure 2(a)), a first inversion step (Figure 1(b)), and a second inversion step (Figure 2(b)). Schematically, in this manufacturing method, an inner ring member 30 is formed by inversion processing in the first inversion step of a first workpiece member 10 prepared in the first preparation step. Similarly, an outer ring member 40 is formed by inversion processing in the second inversion step of a second workpiece member 20 prepared in the second preparation step. In the inversion process, the cross-sectional shape of either the first workpiece member 10 or the second workpiece member 20 is rotated by 90 degrees. Each step will be described below. Note that in all figures except Figure 6, one side of the central axis CL of each member is omitted, but each member has a symmetrical shape with respect to the central axis CL.

[0028] The first preparation step is the step of preparing the first workpiece member 10 (Figure 1(a)). In this example, the first preparation step includes a burring step. As shown in Figure 3, in the burring step, the first workpiece member 10 is formed by burring a ring-shaped processing member 5 to deform the cross-sectional shape of the processing member 5 into a roughly U-shape. The processing member 5 can be formed, for example, by punching out a plate-shaped metal material (punching step). That is, the first preparation step may further include a punching step.

[0029] In the burring process, first, as shown in Figure 3(a), the workpiece 5 is positioned on the spaced-apart inner die 51 and outer die 52 so as to span between the inner die 51 and the outer die 52. Subsequently, as shown in Figure 3(b), the burring punch 53 moves so as to enter between the inner die 51 and the outer die 52, causing the cross-sectional shape of the workpiece 5 to deform from a plate shape to a roughly U-shape.

[0030] More specifically, in the burring process, a deformation suppressing member 54 is used that contacts the workpiece 5 from the opposite side of the burring punch 53, and the burring process is performed while the workpiece 5 is sandwiched between the burring punch 53 and the deformation suppressing member 54. The deformation suppressing member 54 has a spring 54a inside, and as the burring punch 53 moves, it moves while maintaining the state in which the workpiece 5 is sandwiched between the burring punch 53 and the deformation suppressing member 54. In the state shown in Figure 3(b), where the burring punch 53 is inserted between the inner die 51 and the outer die 52, the amount of contraction of the spring 54a is larger compared to the state shown in Figure 3(a) before the burring punch 53 moves, and the biasing force acting on the workpiece 5 is larger. In the burring process, the workpiece 5 is strongly sandwiched, but the deformation suppressing member 54 functions as a cushion, which prevents the workpiece 5 (first workpiece 10) from bending at the point where it is pressed by the burring punch 53.

[0031] The second preparation step is the step of preparing the second workpiece member 20 (Figure 2(a)). In this example, the second preparation step includes a burring step. The burring step is the same as the first preparation step, so its explanation is omitted. In this example, since the shapes of the first workpiece member 10 and the second workpiece member 20 are identical, the burring step can be performed using a common inner die 51 and outer die 52, etc. In other words, in this example, the first workpiece member 10 and the second workpiece member 20 are identical (one type of workpiece member is used), and the first and second preparation steps are common to both.

[0032] In the first inversion step, the inner ring member 30 is formed by inverting the first workpiece member 10 (Figure 1(b)). As shown in Figure 4, in the first inversion step, the inner ring member 30 is formed by axially clamping the first workpiece member 10 between the punch 60 and the die 70 and deforming it so that the first surface 11a faces radially outward. In the first inversion step, the first workpiece member 10 is clamped between the punch 60 and the die 70 with the first surface 11a facing the first side S1 in the axial direction.

[0033] The punch 60 has a punch body 61 and a projection 62. The punch body 61 is formed in a substantially cylindrical shape with an axis parallel to the axial direction. A first R surface R1 is formed on the inner edge of the surface of the second side S2 of the punch body 61. The first R surface R1 is a curved surface formed by rounding the corner of the second side S2 of the punch body 61, and is formed in an arc shape in a cross section parallel to the axial direction (Figure 4). The projection 62 protrudes radially inward from the end of the first side S1 of the punch body 61. The projection 62 is formed, for example, in a cylindrical shape.

[0034] The die 70 has a die body portion 71 and a projection portion 72. The die body portion 71 is formed in a substantially cylindrical shape with an axis parallel to the axial direction. A second R surface R2 is formed on the inner edge of the surface of the first side S1 of the die body portion 71. The second R surface R2 is a curved surface formed by rounding the corner of the first side S1 of the die body portion 71, and is formed in an arc shape in a cross section parallel to the axial direction (Figure 4). The projection portion 72 protrudes radially outward from the end of the second side S2 of the die body portion 71. The projection portion 72 is formed, for example, in a cylindrical shape.

[0035] As shown in Figure 4, in the first inversion step, the first workpiece member 10 is deformed by being sandwiched between the punch body 61 of the punch 60 located on the first side S1 and the die body 71 of the die 70 located on the second side S2. As shown in Figure 4(a), in the initial state, the first body 11 of the first workpiece member 10 is placed on the die 70 with its first surface 11a facing the first side S1. Subsequently, as shown in Figure 4(b), the punch 60 moves to the second side S2 and one of the first flange portions 13 is pressed by the first R surface R1 of the punch body 61, causing the first workpiece member 10 to rise radially outward. Then, as the punch 60 moves further to the second side S2, the projection 62 of the punch 60 contacts the other first flange portion 12 of the first workpiece member 10, and the first workpiece member 10 is pushed to the second side S2 by the projection 62. This inversion process rotates the cross-sectional shape of the first workpiece member 10 by 90 degrees, deforming the first workpiece member 10 so that the first surface 11a faces radially outward. As a result, the first main body portion 11 and the pair of first flange portions 12 and 13 become the main body portion 31 and the pair of flange portions 32 and 33 of the inner ring member 30, respectively, thus obtaining the inner ring member 30. Furthermore, this inversion process causes the first surface 11a of the first main body portion 11 to become the raceway surface 31a of the inner ring member 30.

[0036] In the first reversal step, the first workpiece member 10 is sandwiched between the punch 60 and the die 70 while the first flange portion 12 of the first workpiece member 10 is pushed radially from the inside to the outside by the pressing member 80 (i.e., pushed radially toward the punch 60). As shown in Figure 5, the pressing member 80 is formed in a substantially annular shape as a whole. The pressing member 80 includes a plurality (eight in this example) of block members 80a arranged at equal intervals along the circumferential direction. Each block member 80a is formed, for example, in an annular sector shape. Each block member 80a is positioned on the die 70 and is movable radially along the die 70. As the block members 80a move radially outward, the pressing member 80 pushes the first flange portion 12 radially outward. This pushing force may be a force from any mechanism or power source such as a spring, hydraulics, air, motor, or cam. This pushing force may be, for example, about 0.5 to 5 tonf.

[0037] In the second inversion step, the outer ring member 40 is formed by inverting the second workpiece member 20 (Figure 2(b)). As shown in Figure 6, in the second inversion step, the same punch 60 and die 70 as in the first inversion step are used to form the outer ring member 40 by axially clamping the second workpiece member 20 between the punch 60 and die 70 and deforming it so that the second surface 21a faces radially inward. In the second inversion step, the second workpiece member 20 is clamped between the punch 60 and die 70 with the second surface 21a facing the second side S2 in the axial direction. In other words, in the first and second inversion steps, the orientation of the workpiece members (first workpiece member 10 and second workpiece member 20) is reversed with respect to the axial direction.

[0038] As shown in Figure 6, in the second inversion step, similar to the first inversion step, the second workpiece member 20 is deformed by being sandwiched between the punch body 61 of the punch 60 located on the first side S1 and the die body 71 of the die 70 located on the second side S2. As shown in Figure 6(a), in the initial state, the second body 21 of the second workpiece member 20 is placed on the die 70 with its second surface 21a facing the second side S2. Subsequently, as shown in Figure 6(b), the punch 60 moves to the second side S2 and the second body 21 is pressed by the first R surface R1 of the punch body 61, causing the second workpiece member 20 to rise radially outward. Then, as the punch 60 moves further to the second side S2, the projection 62 of the punch 60 contacts the second flange 22 of the second workpiece member 20, and the second workpiece member 20 is pushed into the second side S2 by the projection 62. This inversion process rotates the cross-sectional shape of the second workpiece member 20 by 90 degrees, deforming the second workpiece member 20 so that the second surface 21a faces radially inward. As a result, the second main body portion 21 and the pair of second flange portions 22 and 23 become the main body portion 41 and the pair of flange portions 42 and 43 of the outer ring member 40, respectively, thus obtaining the outer ring member 40. Furthermore, this inversion process causes the second surface 21a of the second main body portion 21 to become the raceway surface 41a of the outer ring member 40.

[0039] Furthermore, in the second inversion step, similar to the first inversion step, the second flange portion 22 of the second workpiece member 20 is pressed radially from the inside to the outside by the pressing member 80 (i.e., pressed radially toward the punch 60), while the second workpiece member 20 is sandwiched between the punch 60 and the die 70. The same pressing member 80 can be used between the first and second inversion steps.

[0040] In the manufacturing method for bearing ring members of the embodiment, for example, a first reversal step and a second reversal step are performed alternately, and pairs of inner ring ring members 30 and outer ring members 40 are formed sequentially. The manufacturing method for bearing ring members of the embodiment may further include a first inspection step after the first reversal step to inspect whether the inner ring ring member 30 formed in the first reversal step is good or bad. In this case, for example, if the inspection result of the first inspection step is bad, the first reversal step is performed to form the inner ring member 30. This makes it possible to continue forming the inner ring member 30 if, for example, a defect occurs in the inner ring member 30 formed in the first reversal step and the inspection result is bad, thereby preventing a shortage of inner ring member 30.

[0041] Furthermore, the method for manufacturing bearing ring members of the embodiment may further include a second inspection step after the second inversion step to inspect the quality of the outer ring member 40 formed in the second inversion step. In this case, for example, if the inspection result of the second inspection step is negative, the second inversion step is performed to form the outer ring member 40. This allows for the continuous formation of outer ring member 40 if, for example, a defect occurs in the outer ring member 40 formed in the second inversion step and the inspection result is negative, thereby preventing a shortage of outer ring member 40. In addition, by performing the first and second inspection steps (100% inspection), it is possible to manufacture the inner ring member 30 and the outer ring member 40 so that they always come in pairs.

[0042] Alternatively, in the method for manufacturing bearing ring members of the embodiment, the number of inner ring members 30 and outer ring members 40 may be adjusted after each of the first inversion step and the second inversion step has been performed a predetermined number of times (for example, 100 times). For example, the method for manufacturing bearing ring members may further include an information acquisition step of acquiring information regarding the difference between the number of inner ring members 30 formed by the first inversion step and the number of outer ring members 40 formed by the second inversion step, and a replenishment step of performing the first inversion step or the second inversion step so that the number of inner ring members 30 and the number of outer ring members 40 become equal if such a difference exists.

[0043] In the information acquisition process, for example, the number of inner ring members 30 and outer ring members 40 at the present time is counted by an operator or machine, and the difference between the number of inner ring members 30 and the number of outer ring members 40 is calculated. In the replenishment process, for example, if the number of inner ring members 30 is less than the number of outer ring members 40, the first inversion process is performed so that the number of inner ring members 30 becomes equal to the number of outer ring members 40. For example, if the number of inner ring members 30 is three less than the number of outer ring members 40, the first inversion process is performed three times. On the other hand, if the number of outer ring members 40 is less than the number of inner ring members 30, the second inversion process is performed so that the number of outer ring members 40 becomes equal to the number of inner ring members 30. By performing such information acquisition and replenishment processes, it is possible to suppress situations in which there is a shortage of inner ring members 30 or outer ring members 40. [Mechanism of Action and Effects]

[0044] In the manufacturing method for bearing ring members of this embodiment, a common punch 60 and die 70 are used in the first and second inversion steps. In the first inversion step, the inner ring member 30 is formed by sandwiching the first workpiece member 10 between the punch 60 and die 70 with the first surface 11a facing the first side S1 in the axial direction. In the second inversion step, the outer ring member 40 is formed by sandwiching the second workpiece member 20 between the punch 60 and die 70 with the second surface 21a facing the second side S2 opposite to the first side S1. This allows the inner ring member 30 and the outer ring member 40 to be formed using a common punch 60 and die 70, thereby reducing mold costs. Furthermore, for example, if there is a shortage of either the inner ring member 30 or the outer ring member 40, the first or second inversion step can be performed so that the number of inner ring members 30 and outer ring members 40 become equal. As a result, excess inner ring member 30 or outer ring member 40 can be suppressed, and yield can be improved. Therefore, according to the manufacturing method of bearing ring members of this embodiment, the cost of the mold can be reduced and the yield can be improved.

[0045] In the first inversion step, the first workpiece member 10 is pushed radially toward the punch 60 by the pressing member 80, while the first workpiece member 10 is sandwiched between the punch 60 and the die 70. In the second inversion step, the second workpiece member 20 is pushed radially toward the punch 60 by the pressing member 80, while the second workpiece member 20 is sandwiched between the punch 60 and the die 70. This allows the first workpiece member 10 or the second workpiece member 20 to be well sandwiched between the punch 60 and the die 70.

[0046] The first workpiece member 10 and the second workpiece member 20 have the same shape. This makes it possible to form an inner ring member 30 and an outer ring member 40 that have shapes symmetrical with respect to the radial direction, thereby reducing costs.

[0047] The manufacturing method for bearing ring members of the embodiment may include an information acquisition step of acquiring information regarding the difference between the number of inner ring members 30 formed by the first inversion step and the number of outer ring members 40 formed by the second inversion step, and a replenishment step of performing the first inversion step or the second inversion step if such a difference exists, so that the number of inner ring members 30 and the number of outer ring members 40 become equal. In this case, it is possible to reliably suppress the excess of inner ring members 30 or outer ring members 40, and improve the yield.

[0048] The first workpiece member 10 has a pair of first flange portions 12 and 13 that protrude from the first main body portion 11 toward the first surface 11a, and the second workpiece member 20 has a pair of second flange portions 22 and 23 that protrude from the second main body portion 21 toward the second surface 21a. According to the manufacturing method of the bearing ring member of this embodiment, the inner ring member 30 and the outer ring member 40 can be manufactured from the first workpiece member 10 and the second workpiece member 20 having such a U-shaped cross-sectional shape. [Differentiation]

[0049] Figure 7 is a cross-sectional view illustrating the first modified example. Figure 7(a) shows the state at the start of the first inversion process, and Figure 7(b) shows the state at the start of the second inversion process. In the first modified example, the first workpiece member 10 and the second workpiece member 20 have different shapes. That is, two types of workpiece members are used in the first modified example. On the other hand, in the first modified example as well, a common punch 60 and die 70 are used in both the first and second inversion processes. In the first modified example, the die body portion 71 of the die 70 is formed in a substantially cylindrical shape. In the first modified example, the following equations (3) and (4) are satisfied. D1-2×A=d1…(3) D² + 2 × A = d² ... (4) In equations (3) and (4), D1 is the outer diameter (diameter) of the die body 71, d1 is the inner diameter of the first workpiece member 10, D2 is the inner diameter of the punch body 61, and d2 is the outer diameter of the second workpiece member 20.

[0050] Dimension A can be determined by defining the conditions under which either the inner ring member 30 or the outer ring member 40 can be reversed. For example, if the shapes of the punch 60 and die 70 that can reverse-machine the first workpiece member 10 are known, then dimension A in equation (3) can be calculated. By substituting this value of dimension A into equation (4), the outer diameter d2 of the second workpiece member 20 can be determined.

[0051] In the first modified example of the method for manufacturing a bearing ring member, when the first workpiece member 10 is sandwiched between the punch 60 and the die 70 in the first inversion step, the first workpiece member 10 is not pressed by the pressing member 80. Also, when the second workpiece member 20 is sandwiched between the punch 60 and the die 70 in the second inversion step, the second workpiece member 20 is not pressed by the pressing member 80.

[0052] This first modification also reduces mold costs and improves yield, similar to the above embodiment. Furthermore, because the first workpiece member 10 and the second workpiece member 20 have different shapes, it is possible to form an inner ring member 30 and an outer ring member 40 that have radially asymmetric shapes. Also, because equations (3) and (4) are satisfied, the first workpiece member 10 and the second workpiece member 20 can be well sandwiched between the punch 60 and the die 70. In addition, there is no need to use the pressing member 80 in the first and second inversion steps, and the manufacturing equipment can be simplified. Note that in the first and second inversion steps of the first modification, the first workpiece member 10 and the second workpiece member 20 may be pushed toward the punch 60 by the pressing member 80, similar to the above embodiment.

[0053] Figure 8 is a cross-sectional view illustrating a second modified example. In the second modified example's method for manufacturing the bearing ring member, the inner ring member 30 and the outer ring member 40 are formed simultaneously in a single reversal process. The second modified example's method for manufacturing the bearing ring member includes a preparation step of preparing a first workpiece member 10 and a second workpiece member 20, and a reversal step of forming the inner ring member 30 and the outer ring member 40 by sandwiching and deforming the stacked first workpiece member 10 and second workpiece member 20 between a punch 60 and a die 70. In the second modified example, as in the first modified example, the first workpiece member 10 and the second workpiece member 20 have different shapes from each other. The first workpiece member 10 and the second workpiece member 20, as well as the punch 60 and die 70 in the second modified example, have the same shape as those in the first modified example, for example. That is, equations (3) and (4) above are also satisfied in the second modified example.

[0054] The preparation process for the second modified example is the same as the first and second preparation processes in the above embodiment. That is, for example, in the preparation process for the second modified example, the first workpiece member 10 is formed by a burring process, and the second workpiece member 20 is formed by a burring process. As shown in Figure 8, at the start of the inversion process for the second modified example, the first workpiece member 10 and the second workpiece member 20 are stacked on top of each other such that the first surface 11a of the first workpiece member 10 faces the first side S1, and the second surface 21a of the second workpiece member 20 faces the second side S2. In this example, the first workpiece member 10 is placed on the die 70. The second workpiece member 20 is placed on the first workpiece member 10 such that the first surface 11a and the second surface 21a face each other. The first flange portion 12, the second flange portion 22, the first flange portion 13, and the second flange portion 23 are arranged in this order from the inside in the radial direction. From this state, the punch 60 is moved to the second side S2 and the reversal process is performed, which deforms the first workpiece member 10 and the second workpiece member 20 so that the first surface 11a faces radially outward and the second surface 21a faces radially inward, thereby simultaneously forming the inner ring member 30 and the outer ring member 40.

[0055] On the other hand, the inner ring member 30 can also be formed independently by deforming only the first workpiece member 10 by sandwiching it between the punch 60 and the die 70. Furthermore, the outer ring member 40 can also be formed independently by deforming only the second workpiece member 20 by sandwiching it between the punch 60 and the die 70.

[0056] In the second modified method for manufacturing bearing ring members, the first and second inspection steps described above may also be performed. In this case, if the inspection result of the first inspection step is negative, the inner ring member 30 may be formed by sandwiching only the first workpiece member 10 between the punch 60 and the die 70. Also, if the inspection result of the second inspection step is negative, the outer ring member 40 may be formed by sandwiching only the second workpiece member 20 between the punch 60 and the die 70. This makes it possible to prevent situations in which there is a shortage of inner ring members 30 or outer ring members 40.

[0057] Alternatively, similar to the above embodiment, in the second modified method for manufacturing bearing ring members, the number of inner ring members 30 and outer ring members 40 may be adjusted after the reversal process has been performed a predetermined number of times (for example, 100 times). For example, the second modified method for manufacturing bearing ring members may further include an information acquisition step of acquiring information regarding the difference between the number of inner ring members 30 formed by the reversal process and the number of outer ring members 40 formed by the reversal process, and a replenishment step of forming inner ring members 30 or outer ring members 40 by sandwiching the first workpiece member 10 or second workpiece member 20 between a punch 60 and a die 70 so that the number of inner ring members 30 and outer ring members 40 become equal to each other if such a difference exists.

[0058] In the replenishment process, for example, if the number of inner ring members 30 is less than the number of outer ring members 40, the first workpiece member 10 is sandwiched between the punch 60 and the die 70 to form the inner ring members 30 so that the number of inner ring members 30 becomes equal to the number of outer ring members 40. On the other hand, if the number of outer ring members 40 is less than the number of inner ring members 30, the second workpiece member 20 is sandwiched between the punch 60 and the die 70 to form the outer ring members 40. By implementing such information acquisition and replenishment processes, it is possible to suppress situations in which there is a shortage of either the inner ring members 30 or the outer ring members 40.

[0059] This second modified example, like the embodiment described above, can reduce mold costs and improve yield. Specifically, in the second modified example of the bearing ring member manufacturing method, the inner ring member 30 and the outer ring member 40 are formed by sandwiching the stacked first work member 10 and second work member 20 between a punch 60 and a die 70. This allows the inner ring member 30 and the outer ring member 40 to be formed using a common punch 60 and die 70, thereby reducing mold costs. Furthermore, for example, if there is a shortage of either the inner ring member 30 or the outer ring member 40, the first work member 10 or the second work member 20 can be sandwiched between the punch 60 and die 70 so that the number of inner ring members 30 and outer ring members 40 are equal, thereby forming the inner ring member 30 or the outer ring member 40. As a result, the excess of the inner ring member 30 or the outer ring member 40 can be suppressed, and the yield can be improved.

[0060] Figure 9 is a cross-sectional view illustrating a third modified example. In the manufacturing method of the bearing ring member of the third modified example, similar to the second modified example, the inner ring member 30 and the outer ring member 40 are formed simultaneously by a single reversal process. In the third modified example as well, the first workpiece member 10 and the second workpiece member 20 have different shapes. The manufacturing method of the bearing ring member of the third modified example comprises, similar to the second modified example, a preparation step of preparing the first workpiece member 10 and the second workpiece member 20, and a reversal step of forming the inner ring member 30 and the outer ring member 40 by sandwiching and deforming the stacked first workpiece member 10 and the second workpiece member 20 between a punch 60 and a die 70.

[0061] At the start of the inversion process in the third modified example, the first workpiece member 10 is stacked so that its first surface 11a faces the first side S1 and its second surface 21a faces the second side S2. In this example, the second workpiece member 20 is placed inside the first workpiece member 10, with the first flange portion 12, the second flange portion 22, the second flange portion 23, and the first flange portion 13 arranged in this order from the inside in the radial direction. By moving the punch 60 to the second side S2 from this state and performing the inversion process, the first workpiece member 10 and the second workpiece member 20 are deformed so that the first surface 11a faces the outside in the radial direction and the second surface 21a faces the inside in the radial direction, thereby simultaneously forming the inner ring member 30 and the outer ring member 40.

[0062] In the inversion step of the third modified example, the first workpiece member 10 is pushed radially toward the punch 60 by the pressing member 80, while the first workpiece member 10 and the second workpiece member 20 are sandwiched between the punch 60 and the die 70. This third modified example, like the second modified example, can reduce mold costs and improve yield. In the inversion step of the third modified example, depending on the shapes of the first workpiece member 10 and the second workpiece member 20, the second workpiece member 20 may be pushed radially toward the punch 60 by the pressing member 80 instead of the first workpiece member 10, while the first workpiece member 10 and the second workpiece member 20 are sandwiched between the punch 60 and the die 70.

[0063] The present invention is not limited to the embodiments and modifications described above. For example, the materials and shapes of each component are not limited to those described above, but can be made from a variety of materials and shapes.

[0064] For example, the first workpiece member 10, the second workpiece member 20, the inner ring member 30, and the outer ring member 40 may have the shapes shown in Figures 10 and 11. Figures 10(a), 10(b), 11(a), and 11(b) show examples where the bearing is a deep groove ball bearing, an angular contact bearing, a cylindrical bearing, and a conical bearing, respectively. When the bearing is a self-aligning ball bearing or a self-aligning roller bearing, the configuration is the same as when the bearing is a cylindrical bearing.

[0065] In the example shown in Figure 10(a), the first workpiece member 10 and the second workpiece member 20 have the same shape. In the examples shown in Figures 10(b), 11(a), and 11(b), the first workpiece member 10 and the second workpiece member 20 have different shapes. As shown in Figures 10 and 11, the first workpiece member 10 does not have to have first flange portions 12, 13, and the second workpiece member 20 does not have to have second flange portions 22, 23. The inner ring member 30 does not have to have flange portions 32, 33, and the outer ring member 40 does not have to have flange portions 42, 43. The first surface 11a, the second surface 21a, and the raceway surfaces 31a, 41a may be curved or inclined surfaces.

[0066] In the above embodiments and their respective modifications, the punch body portion 61 is formed in a substantially cylindrical shape, and the die body portion 71 is formed in a substantially cylindrical or substantially cylindrical shape. However, conversely, the punch body portion 61 may be formed in a substantially cylindrical or substantially cylindrical shape, and the die body portion 71 may be formed in a substantially cylindrical shape. That is, in the above embodiments and their respective modifications, the punch body portion 61 is located radially outward relative to the die body portion 71. Conversely, the punch body portion 61 may be located radially inward relative to the die body portion 71. In this case, for example, the projection portion 62 protrudes radially inward from the punch body portion 61, and the projection portion 72 protrudes radially outward from the die body portion 71. When such a punch 60 and die 70 are used, in the first reversal step, the first workpiece member 10 may be sandwiched between the punch 60 and die 70 while the first flange portion 13 of the first workpiece member 10 is pushed from the radial outside to the inside by the pressing member 80 (i.e., pushed radially toward the punch 60). Similarly, in the second reversal step, the second workpiece member 20 may be sandwiched between the punch 60 and die 70 while the second flange portion 23 of the second workpiece member 20 is pushed from the radial outside to the inside by the pressing member 80 (i.e., pushed radially toward the punch 60).

[0067] In the inversion step of the above embodiment and each of its modifications, the workpiece member is sandwiched between the punch 60 and the die 70 as the punch 60 approaches the die 70. However, it is sufficient for the punch 60 and the die 70 to move relative to each other; for example, the workpiece member may be sandwiched between the punch 60 and the die 70 as they move closer to each other. In the above embodiment, the first workpiece member 10 and the second workpiece member 20 may have different shapes. In the first and second modifications, the first workpiece member 10 and the second workpiece member 20 may have the same shape. In the method for manufacturing a bearing ring member of the embodiment, the order in which the first inversion step and the second inversion step are performed is not limited, and the first inversion step may be performed after the second inversion step. [Explanation of Symbols]

[0068] 10...First workpiece member, 11...First main body, 11a...First surface, 12,13...First flange portion, 20...Second workpiece member, 21...Second main body, 21a...Second surface, 22,23...Second flange portion, 30...Inner ring member, 31a...Raceway surface, 40...Outer ring member, 41a...Raceway surface, 60...Punch, 70...Die, 80...Pressing member, S1...First side, S2...Second side.

Claims

1. A method for manufacturing a bearing ring member, A first inversion step in which a ring member for the inner ring is formed by axially clamping a first workpiece member having an annular first main body portion including a first surface that serves as a raceway surface between a punch and a die, and deforming it so that the first surface faces radially outward, The process includes a second reversal step of forming an outer ring member by axially clamping a second workpiece member, which has an annular second main body portion including a second surface that serves as a raceway surface, between the punch and the die, thereby deforming it so that the second surface faces radially inward, In the first inversion step, the first workpiece is clamped between the punch and the die with the first surface facing the first side in the axial direction, and in the second inversion step, the second workpiece is clamped between the punch and the die with the second surface facing the second side opposite to the first side. In the first reversal step, the first workpiece is pressed radially toward the punch by the pressing member, while the first workpiece is sandwiched between the punch and the die. A method for manufacturing a bearing ring member, wherein in the second reversal step, the second workpiece member is pressed radially toward the punch by the pressing member, while the second workpiece member is sandwiched between the punch and the die.

2. A method for manufacturing a bearing ring member, A step of preparing a first workpiece member having an annular first main body portion including a first surface that serves as a raceway surface, and a second workpiece member having an annular second main body portion including a second surface that serves as a raceway surface, A method for manufacturing a ring member for a bearing, comprising: a reversal step of forming an inner ring member and an outer ring member by axially sandwiching a first work member and a second work member, which are stacked such that the first surface faces the first side in the axial direction and the second surface faces the second side opposite to the first side, between a punch and a die, thereby deforming them so that the first surface faces radially outward and the second surface faces radially inward.

3. The method for manufacturing a bearing ring member according to claim 2, wherein in the inversion step, the first work member or the second work member is pushed radially toward the punch by a pressing member, and the first work member and the second work member are sandwiched between the punch and the die.

4. A method for manufacturing a bearing ring member according to any one of claims 1 to 3, wherein the first workpiece member and the second workpiece member have the same shape as each other.

5. A method for manufacturing a bearing ring member according to any one of claims 1 to 3, wherein the first workpiece member and the second workpiece member have different shapes from each other.

6. A method for manufacturing a bearing ring member, A first inversion step in which a ring member for the inner ring is formed by axially clamping a first workpiece member having an annular first main body portion including a first surface that serves as a raceway surface between a punch and a die, and deforming it so that the first surface faces radially outward, The process includes a second reversal step of forming an outer ring member by axially clamping a second workpiece member, which has an annular second main body portion including a second surface that serves as a raceway surface, between the punch and the die, thereby deforming it so that the second surface faces radially inward, In the first inversion step, the first workpiece is clamped between the punch and the die with the first surface facing the first side in the axial direction, and in the second inversion step, the second workpiece is clamped between the punch and the die with the second surface facing the second side opposite to the first side. A method for manufacturing a bearing ring member, wherein the first workpiece member and the second workpiece member have different shapes from each other.

7. The punch has a cylindrical punch body, The die has a cylindrical or columnar die body that sandwiches at least one of the first workpiece member and the second workpiece member between itself and the punch body. A method for manufacturing a bearing ring member according to any one of claims 1 to 6, wherein formula (1) and formula (2) are satisfied. D １ -2×A=d １ …(1) D ２ +2×A=d ２ …(2) In the above formulas (1) and (2), D １ d is the outer diameter of the die body, １ D is the inner diameter of the first workpiece member. ２ d is the inner diameter of the punch body, ２ This is the outer diameter of the second workpiece member.

8. A step of obtaining information regarding the difference between the number of inner ring members formed by the first inversion step and the number of outer ring members formed by the second inversion step, A method for manufacturing a bearing ring member according to claim 1 or 6, further comprising the step of performing the first reversal step or the second reversal step so that, if the aforementioned difference exists, the number of inner ring members and the number of outer ring members become equal to each other.

9. A step of obtaining information regarding the difference between the number of inner ring members formed by the inversion step and the number of outer ring members formed by the inversion step, A method for manufacturing a bearing ring member according to claim 2 or 3, further comprising the step of forming the inner ring member or the outer ring member by sandwiching the first workpiece member or the second workpiece member between the punch and the die such that, if the aforementioned difference exists, the number of inner ring members and the number of outer ring members are equal to each other.

10. The first workpiece member has a pair of first flange portions that protrude from the first main body toward the first surface, The method for manufacturing a bearing ring member according to any one of claims 1 to 9, wherein the second workpiece member has a pair of second flange portions protruding from the second main body toward the second surface.

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