Manufacturing method of hub unit bearing, swing pressing device and manufacturing method of vehicle

Abstract

A manufacturing method of a hub unit bearing capable of improving the machining efficiency of a pressing portion. In a state where the hub ring (22) is arranged such that the central axis of the hub ring (22) is coaxial or parallel with the reference axis C and is supported in a manner that allows the hub ring (22) to move radially, a die (31) having a rotation axis α inclined with respect to the reference axis C is pressed against the inner axial end portion of the hub ring (22), and the die (31) is rotated about the reference axis C, thereby machining the inner axial end portion of the hub ring (22) into a pressing portion (26).

Description

Technical Field

[0001] The present invention relates to a manufacturing method of a hub unit bearing for rotatably supporting a wheel of a vehicle such as an automobile relative to a suspension device, a swing pressing device for implementing the manufacturing method, and a manufacturing method of a vehicle. Background Art

[0002] A wheel of an automobile and a rotating body for braking are rotatably supported relative to a suspension device by a hub unit bearing. Figure 8 An example of a conventionally known hub unit bearing is shown. The hub unit bearing 100 rotatably supports a hub 102 on the inner diameter side of an outer ring 101 via a plurality of rolling elements 103a, 103b.

[0003] In addition, with respect to the hub unit bearing 100, in a state where the hub unit bearing 100 is assembled to an automobile, the axially outer side becomes the outer side in the vehicle body width direction, that is, Figure 8 the left side, and in a state where the hub unit bearing 100 is assembled to an automobile, the axially inner side becomes the center side in the vehicle body width direction, that is, Figure 8 the right side.

[0004] The outer ring 101 has a plurality of rows of outer ring raceways 104a, 104b on the inner peripheral surface, and has a stationary flange 105 for supporting and fixing the outer ring 101 to a knuckle of a suspension device at an axially intermediate portion. The hub 102 has a plurality of rows of inner ring raceways 106a, 106b on the outer peripheral surface, and has a rotating flange 107 for supporting and fixing a wheel and a rotating body for braking to the hub 102 and a cylindrical guide portion 108 at an axially outer portion. At the axially outer portion of the hub 102, the rotating flange 107 projects radially outward, and the guide portion 108 extends axially outward from a portion adjacent to the radially inner side of the rotating flange 107. A plurality of rolling elements 103a, 103b are respectively arranged in each row between the plurality of rows of outer ring raceways 104a, 104b and the plurality of rows of inner ring raceways 106a, 106b. With such a structure, the hub 102 is rotatably supported on the inner diameter side of the outer ring 101.

[0005] In the illustrated example, the hub 102 is assembled from a hub ring 109 and an inner ring 110. The hub ring 109 has, on the outer peripheral surface of the axial middle portion, the axially outer inner ring raceways 106a among the multiple inner ring raceways 106a, 106b, and has a rotary flange 107 and a guide portion 108 at the axially outer portion. Further, the hub ring 109 has a fitting shaft portion 111 with an outer diameter smaller than that of the portion adjacent to the axially outer side at the axially inner portion. The inner ring 110 has the axially inner inner ring raceway 106b on the outer peripheral surface. Such an inner ring 110 is externally fitted to the fitting shaft portion 111 by press-fitting in a state where the axially outer end surface abuts against the step surface 112 existing at the axially outer end portion of the outer peripheral surface of the fitting shaft portion 111. In this state, the axially inner end surface of the inner ring 110 is pressed by a pressing portion 113 formed by plastically deforming a cylindrical portion extending axially inward from the axially inner end of the fitting shaft portion 111 radially outward. And by pressing the axially inner end surface of the inner ring 110 with the pressing portion 113 like this, appropriate preload is imparted to the rolling elements 103a, 103b.

[0006] As a device for forming the pressing portion 113 as described above, Figure 9 a swing pressing device 114 as shown (for example, refer to Japanese Patent Application Laid-Open No. 2012-45612 (Patent Document 1), Japanese Patent No. 5261023 (Patent Document 2)) is known. The swing pressing device 114 includes a die 115 and a holder 116. The holder 116 functions as a bracket for supporting the load applied to the hub ring 109 from the die 115, and has a flange receiving surface 117 provided on the upper side surface and an insertion hole 118 opened on the flange receiving surface 117.

[0007] When forming the pressing portion 113, the guide portion 108 of the hub ring 109 is inserted into the insertion hole 118 of the holder 116 without radial play, and the axially outer side surface of the rotary flange 107 of the hub ring 109 is brought into contact with the flange receiving surface 117 of the holder 116. Thereby, the hub ring 109 is supported by the holder 116 in a state where the radial movement of the hub ring 109 is blocked.

[0008] Then, in this state, the die 115 having a rotation axis inclined with respect to the central axis of the wheel rim 109 is pressed against the axially inner end portion (cylindrical portion) of the wheel rim 109, and the die 115 is rotated about the central axis of the wheel rim 109, whereby the axially inner end portion of the wheel rim 109 is processed into the pressing portion 113. That is, a processing force that is directed downward in the vertical direction and outward in the radial direction is applied to a part of the circumferential direction of the axially inner end portion of the wheel rim 109 from the die 115. In addition, the position where this processing force is applied continuously changes in the circumferential direction of the axially inner end portion of the wheel rim 109 as the die 115 rotates about the central axis of the wheel rim 109. Thus, the pressing portion 113 is formed by plastically deforming the axially inner end portion of the wheel rim 109 outward in the radial direction.

[0009] Prior Art Documents

[0010] Patent Documents

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 2012-45612

[0012] Patent Document 1: Japanese Patent No. 5261023 Summary of the Invention

[0013] In addition, in the case of forming the pressing portion 113 as described above, the swing pressing device 114 generates energy for pressing the die 115 against the axially inner end portion of the wheel rim 109 and energy for rotating the die 115 about the central axis (reference axis) of the wheel rim 109. However, not all of these energies ( Figure 10 input energy E1) are consumed as energy for forming the pressing portion 113 ( Figure 10 output energy E2). That is, a part of the input energy E1 is consumed as energy ( Figure 10 loss energy E3) for deforming and vibrating parts other than the axially inner end portion of the wheel rim 109 among the components constituting the swing pressing device 114 and the components constituting the wheel unit bearing 100. Therefore, in order to improve the processing efficiency of the pressing portion 113, that is, to increase the ratio (E2 / E1) of the output energy E2 to the input energy E1, it is desirable to reduce the loss energy E3.

[0014] In response to this, in the above-described conventional method, the guide portion 108 of the wheel rim 109 is inserted into the insertion hole 118 of the holder 116 without radial play, and the pressing portion 113 is processed in a state where the radial movement of the wheel rim 109 is blocked. Therefore, in this processing, there is a problem to be improved that the swing pressing device 114 is likely to vibrate and the loss energy E3 is likely to increase accordingly.

[0015] In view of the above circumstances, an object of the present invention is to provide a manufacturing method of a wheel unit bearing, a swing pressing device, and a manufacturing method of a vehicle, which can improve the processing efficiency of the pressing portion.

[0016] The wheel unit bearing to be manufactured in the present invention includes: an outer ring having multiple rows of outer raceways on its inner peripheral surface; a hub having multiple rows of inner raceways on its outer peripheral surface; and a plurality of rolling elements respectively arranged between the multiple rows of outer raceways and the multiple rows of inner raceways. The hub has an inner ring and a hub ring. The inner ring has an inner raceway on the axial inner side among the multiple rows of inner raceways on its outer peripheral surface. The hub ring has: a rotating flange protruding radially outward from the axial outer portion; a cylindrical guiding portion extending axially outward from a portion adjacent to the radial inner side of the rotating flange; an inner raceway on the axial outer side among the multiple rows of inner raceways formed directly or via other components on the outer peripheral surface of a portion located axially inner than the rotating flange; a fitting shaft portion axially inner than the axial outer inner raceway and fittingly engaging the inner ring on the outside; and a pressing portion formed by plastically deforming a cylindrical axial inner end portion located axially inner than the fitting shaft portion radially outward and pressing the axial inner end face of the inner ring.

[0017] The manufacturing method of the wheel unit bearing of the present invention includes a pressing step. In this pressing step, with the hub ring arranged such that its central axis is coaxial or parallel with a reference axis and supported by a holding seat in a state where it can move radially, a die having a rotation axis inclined with respect to the reference axis is pressed against the axial inner end portion of the hub ring, and the die is rotated around the reference axis while rotating around the rotation axis, thereby processing the axial inner end portion of the hub ring into the pressing portion.

[0018] In the first aspect of the manufacturing method of the wheel unit bearing of the present invention, the guiding portion is inserted into an insertion hole that opens on a flange receiving surface of the holding seat and is arranged coaxially with the reference axis and has an inner diameter larger than the outer diameter of the guiding portion, and the axial outer side surface of the rotating flange is brought into contact with the flange receiving surface, thereby arranging the hub ring such that its central axis is coaxial or parallel with the reference axis and supporting it in a state where it can move radially.

[0019] In the first aspect of the above manufacturing method, for example, the difference in diameter, that is, the diameter difference, between the inner diameter of the insertion hole and the outer diameter of the guiding portion is determined based on the sum of the total energy required for the die to rotate around the reference axis and the total energy required for pressing the die against the axial inner end portion of the hub ring in the pressing step, that is, the energy sum.

[0020] In this case, for example, in the range where the sum of the above energies is below a specified value, the above diameter difference is determined. Or, for example, in the range where the sum of the above energies is substantially fixed, the above diameter difference is determined. Or, for example, in the range where the change amount of the above sum of energies with respect to the change amount of the above diameter difference is below a specified value, the above diameter difference is determined.

[0021] In the first aspect of the above manufacturing method, for example, by integrating the torque for rotating the above die around the above reference axis with the rotation angle of the above die around the above reference axis, the total energy required to rotate the above die around the above reference axis in the above pressing process is obtained.

[0022] In the first aspect of the above manufacturing method, for example, by integrating the load for pressing the axial inner ends of the above die and the above hub ring in the direction of the above reference axis with the relative movement amount of the above holding seat and the above die in the direction with respect to the above reference axis, the total energy required to press the above die against the axial inner end of the above hub ring in the above pressing process is obtained.

[0023] In the first aspect of the above manufacturing method, for example, the above pressing process is started in a state where the central axis of the above hub ring is coaxially arranged with the above reference axis.

[0024] In this case, for example, by fitting the above guiding portion inserted into the above insertion hole into a cylindrical centering jig arranged coaxially with the above reference axis, a state where the central axis of the above hub ring is coaxially arranged with the above reference axis is achieved. Then, while maintaining the state where the central axis of the above hub ring is coaxially arranged with the above reference axis, the above pressing process is started in a state where the above centering jig is retracted axially from the above guiding portion.

[0025] In the second aspect of the manufacturing method of the hub unit bearing of the present invention, the above guiding portion is inserted into an insertion hole opened on the flange receiving surface of a holding seat capable of moving in a direction orthogonal to the above reference axis, and the axially outer surface of the above rotating flange is brought into contact with the above flange receiving surface, thereby arranging the above hub ring such that the central axis of the hub ring is coaxial or parallel with the above reference axis and supporting the hub ring such that it can move radially.

[0026] In the second aspect of the above manufacturing method, for example, the above pressing process is started in a state where the central axis of the above hub ring is coaxially arranged with the above reference axis.

[0027] The first embodiment of the swing pressing device of the present invention includes a reference axis, a holding seat, a pressing die, and a centering jig. The holding seat has a flange receiving surface and an insertion hole. The flange receiving surface is provided on a side surface of the holding seat on one side in the direction of the reference axis, and is used for the outer axial surface of the rotating flange to contact therewith. The insertion hole opens on the flange receiving surface and is coaxially arranged with the reference axis, and has an inner diameter larger than the outer diameter of the guiding portion. The pressing die is arranged on one side of the holding seat in the direction of the reference axis, has a self-rotating axis inclined with respect to the reference axis, and can rotate about the reference axis and perform relative movement with the holding seat in the direction of the reference axis. The centering jig is a cylindrical jig coaxially arranged with the reference axis inside the insertion hole, and can switch between a state in which the central axis of the hub ring is coaxially arranged with the reference axis by fitting the guiding portion inserted into the insertion hole, and a state in which the hub ring can move radially by retracting from the guiding portion in the axial direction.

[0028] The second embodiment of the swing pressing device of the present invention includes a reference axis, a holding seat, a pressing die, and a centering jig. The holding seat has a flange receiving surface and an insertion hole, and is supported in such a way that it can move in a direction orthogonal to the reference axis. The flange receiving surface is provided on a side surface of the holding seat on one side in the direction of the reference axis, and is used for the outer axial surface of the rotating flange to contact therewith. The insertion hole opens on the flange receiving surface and is used for inserting the guiding portion. The pressing die is arranged on one side of the holding seat in the direction of the reference axis, has a self-rotating axis inclined with respect to the reference axis, and can rotate about the reference axis and perform relative movement with the holding seat in the direction of the reference axis.

[0029] In the second embodiment of the swing pressing device, for example, it further includes: a support table that is blocked from moving in a direction orthogonal to the reference axis; a movable table; an X-direction linear guide that supports the movable table in such a way that it can move in one direction, i.e., the X direction, orthogonal to the reference axis; and a Y-direction linear guide that supports the holding seat with respect to the movable table in such a way that it can move in a Y direction that is orthogonal to both the reference axis and the X direction.

[0030] In the second embodiment of the swing pressing device, for example, it further includes a spring that applies a force to the holding seat in the direction in which the central axis of the insertion hole and the reference axis coincide when the holding seat moves and the central axes of the insertion hole and the reference axis become non-coincident.

[0031] The vehicle to be manufactured according to the present invention is equipped with a wheel hub unit bearing. The manufacturing method of the vehicle according to the present invention manufactures the above-mentioned wheel hub unit bearing by the manufacturing method of the wheel hub unit bearing according to the present invention.

[0032] Advantages of the Invention

[0033] According to the present invention, the processing efficiency of the pressing portion can be improved. Description of the Drawings

[0034] Figure 1 It is a cross-sectional view showing the wheel hub unit bearing to be the object of manufacture of the first example of the embodiment in a state of being assembled to a vehicle.

[0035] Figure 2 It is a cross-sectional view showing a state where the wheel hub unit bearing is provided in a swing pressing device with respect to the first example of the embodiment.

[0036] Figure 3 It is a cross-sectional view showing a state where a pressing portion is formed by a swing pressing device with respect to the first example of the embodiment.

[0037] Figure 4 In Figure 4 (A) is a graph showing the relationship between the total rotation angle of the die and the die rotation torque during the pressing process, Figure 4 (B) is a graph showing the relationship between the axial displacement amount of the die and the axial load of the die during the pressing process.

[0038] Figure 5 It is a graph showing the relationship between the difference in diameter, that is, the difference between the inner diameter of the insertion hole of the retainer and the outer diameter of the guide portion of the wheel hub ring, and the energy sum generated for performing the pressing process.

[0039] Figure 6 It is a cross-sectional view showing a state where the wheel hub unit bearing is provided in a swing pressing device with respect to the second example of the embodiment.

[0040] Figure 7 It is a perspective view schematically showing a support portion of the wheel hub unit bearing and a part of the wheel hub unit bearing constituting the swing pressing device with respect to the second example of the embodiment.

[0041] Figure 8 It is a half cross-sectional view showing an example of a wheel hub unit bearing known in the past.

[0042] Figure 9 It is a cross-sectional view showing a known swing pressing device and a wheel hub unit bearing.

[0043] Figure 10It is a diagram showing the relationship among the input energy E1, the output energy E2, and the loss energy E3 when forming the pressing portion of the hub unit bearing. Detailed implementation

[0044] [First example of the implementation]

[0045] Use Figures 1 to 5 Explain the first example of the implementation of the present invention.

[0046] (Summary of this example)

[0047] In this example, in order to form the pressing portion 26 of the hub ring 22 constituting the hub unit bearing 1 as shown, use Figure 1 and the swing pressing device 28 as shown. In addition, in order to improve the processing efficiency of the pressing portion 26, as shown in Figure 2 and Figure 3 , by making the inner diameter D of the insertion hole 33 of the holding seat 29 constituting the swing pressing device 28 larger than the outer diameter d of the guiding portion 13 of the hub ring 22 (D>d), a radial gap 37 is provided between the inner peripheral surface of the insertion hole 33 of the holding seat 29 and the outer peripheral surface of the guiding portion 13 of the hub ring 22. Thus, during the processing for forming the pressing portion 26, the hub ring 22 can move radially relative to the holding seat 29. However, at the start of the processing for forming the pressing portion 26, the central axis of the hub ring 22 is arranged coaxially with the central axis of the insertion hole 33, that is, the reference axis C in advance. Figure 3

[0048] Hereinafter, after explaining the structure of the hub unit bearing 1 which is the manufacturing object of this example, the structure of the swing pressing device 28 for forming the pressing portion 26, and the manufacturing method of the hub unit bearing 1, explain the setting method of the diameter difference δ (= D - d, the difference between the inner diameter D of the insertion hole 33 and the outer diameter d of the guiding portion 13) that can sufficiently improve the processing efficiency of the pressing portion 26.

[0049] (Structure of the hub unit bearing 1)

[0050] Figure 1 The hub unit bearing 1 which is the manufacturing object of this example is shown. The hub unit bearing 1 is for a driven wheel and includes an outer ring 2, a hub 3, and a plurality of rolling elements 4a, 4b.

[0051] In addition, regarding the hub unit bearing 1, when assembled to a vehicle, the axially outer side becomes the outer side in the vehicle width direction, that is, Figure 1 the left side, and when assembled to a vehicle, the axially inner side becomes the central side in the vehicle width direction, that is, Figure 1 the right side.

[0052] The outer ring 2 is made of a hard metal such as medium carbon steel, and has multiple rows of outer ring raceways 5a, 5b and a stationary flange 6. The multiple rows of outer ring raceways 5a, 5b are formed on the inner peripheral surface of the axial middle part of the outer ring 2, and are partial conical concave surfaces that are inclined in a direction in which the diameter becomes larger as they go in a direction away from each other axially. The stationary flange 6 protrudes radially outward from the axial middle part of the outer ring 2, and has support holes 7 as threaded holes at multiple positions in the circumferential direction.

[0053] The outer ring 2 is supported and fixed to the knuckle 8 by screwing a bolt 10 inserted through a through hole 9 of the knuckle 8 constituting a suspension device of a vehicle from the axial inner side into the support hole 7 of the stationary flange 6 and tightening it.

[0054] The hub 3 is arranged coaxially with the outer ring 2 on the radially inner side of the outer ring 2, and has multiple rows of inner ring raceways 11a, 11b, a rotating flange 12 and a guiding portion 13. The multiple rows of inner ring raceways 11a, 11b are formed on the portion of the outer peripheral surface of the hub 3 that faces the multiple rows of outer ring raceways 5a, 5b, and are partial conical convex surfaces that are inclined in a direction in which the diameter becomes larger as they go in a direction away from each other axially. The rotating flange 12 protrudes radially outward from the axial outer part of the hub 3 that is axially outside the outer ring 2, and has mounting holes 14 at multiple positions in the circumferential direction. The guiding portion 13 is a cylindrical portion that extends axially outward from a portion adjacent to the radially inner side of the rotating flange 12 in the axial outer part of the hub 3 that is axially outside the outer ring 2. In addition, the outer peripheral surface of the guiding portion 13 is a stepped cylindrical surface having a large-diameter portion 44 in the shape of a cylindrical surface constituting the axially inner part and a small-diameter portion 45 in the shape of a cylindrical surface having an outer diameter smaller than that of the large-diameter portion 44 and constituting the axially outer part.

[0055] In addition, in the illustrated example, in order to fixedly couple a braking rotating body 15 such as a brake disc or a brake drum to the rotating flange 12, in a state where the braking rotating body 15 is externally fitted to the axially inner part (large-diameter portion 44) of the guiding portion 13, the fine-tooth portion provided at the proximal end portion of the stud bolt 16 is pressed into the mounting hole 14, and the middle portion of the stud bolt 16 is pressed into the through hole 17 of the braking rotating body 15. Moreover, in order to fix a wheel 18 constituting a wheel to the rotating flange 12, in a state where the wheel 18 is externally fitted to the axially outer part (small-diameter portion 45) of the guiding portion 13 and in a state where an external thread portion provided at the front end portion of the stud bolt 16 is inserted through a through hole 19 of the wheel 18, a nut 20 is screwed onto the external thread portion and tightened.

[0056] The rolling elements 4a and 4b are made of hard metal such as bearing steel or ceramic, and a plurality of them are arranged in each column between the multi-row outer raceways 5a and 5b and the multi-row inner raceways 11a and 11b. In addition, the rolling elements 4a and 4b are rotatably held by the cages 21a and 21b in each column. Furthermore, in this example, the rolling elements 4a and 4b are tapered rollers respectively.

[0057] In this example, the hub 3 is composed of a hub ring 22 made of hard metal such as medium carbon steel and an inner ring 23 made of hard metal such as bearing steel.

[0058] The hub ring 22 has the axially outer inner raceway 11a of the multi-row inner raceways 11a and 11b on the outer peripheral surface of the axially intermediate portion, and has a rotary flange 12 and a guide portion 13 at the axially outer portion. In addition, the hub ring 22 has a fitting shaft portion 24 with an outer diameter smaller than that of the portion adjacent to the axially outer side at the axially inner portion located axially inside compared with the axially outer inner raceway 11a. The inner ring 23 has the axially inner inner raceway 11b of the multi-row inner raceways 11a and 11b on the outer peripheral surface. Such an inner ring 23 is externally fitted to the fitting shaft portion 24 by press-fitting in a state where the axially outer end surface abuts against the stepped surface 25 existing at the axially outer end portion of the outer peripheral surface of the fitting shaft portion 24. In this state, the axially inner end surface of the inner ring 23 is pressed by the pressing portion 26 formed by plastically deforming the cylindrical portion 27 extending radially outward from the axially inner end portion of the fitting shaft portion 24. And by pressing the axially inner end surface of the inner ring 23 with the pressing portion 26 like this, an appropriate preload is given to the rolling elements 4a and 4b.

[0059] (Structure of the swing pressing device 28)

[0060] Next, while referring to Figure 2 and Figure 3 the swing pressing device 28 for forming the pressing portion 26 will be described. The swing pressing device 28 includes a reference axis C in the vertical direction, a holding base 29, a die 31, and a centering jig 30.

[0061] The holding base 29 functions as a bracket that supports the load applied to the wheel rim 22 from the die 31 when forming the pressing portion 26. The holding base 29 has a flange receiving surface 32 provided on the upper side surface and an insertion hole 33 that opens on the flange receiving surface 32. The flange receiving surface 32 is a flat surface orthogonal to the reference axis C. The insertion hole 33 is a bottomed hole having a cylindrical inner peripheral surface arranged coaxially with the reference axis C. The inner diameter D of the insertion hole 33 is larger than the outer diameter d of the guiding portion 13 of the wheel rim 22 (D>d). Here, the outer diameter d is the outer diameter of the large diameter portion 44 of the guiding portion 13. In addition, the axial depth of the insertion hole 33 is larger than the axial dimension of the guiding portion 13 of the wheel rim 22. The holding base 29 having such a structure is supported by a support table (not shown) in a state where movement in a direction orthogonal to the reference axis C and movement in the vertical direction along the reference axis C are blocked. However, in the case of implementing the present invention, it is also possible that the holding base 29 is supported in such a manner that it can move in the vertical direction along the reference axis C, and a load for forming the pressing portion 26 is generated by upward movement.

[0062] The die 31 is a tool for forming the pressing portion 26 and is arranged above the holding base 29. The die 31 has a rotation axis α inclined at an angle θ with respect to the reference axis C and has a circular concave surface, i.e., a machining surface 36, coaxial with the rotation axis α at the lower end portion. The die 31 can move in the vertical direction along the reference axis C and rotate about the reference axis C, and can freely rotate about the rotation axis β. In addition, in the case of implementing the present invention, in the case where a load for forming the pressing portion 26 is generated by upward movement of the holding base 29 as described above, it is also possible to support the die 31 in a state where movement in the vertical direction along the reference axis C is blocked.

[0063] The centering jig 30 is a jig for coaxially arranging the central axis of the wheel rim 22 with the reference axis C before starting to form the pressing portion 26. The centering jig 30 is configured in a cylindrical shape, is arranged coaxially with the reference axis C inside the insertion hole 33 of the holding base 29, and can move in the vertical direction along the reference axis C. Therefore, in the illustrated example, the centering jig 30 is embedded inside the insertion hole 33 in such a manner that there is no radial (horizontal direction) wobbling and it can move axially (vertical direction). In addition, the lower end portion of the centering jig 30 penetrates the central portion of the holding base 29 in the vertical direction and is connected to the upper end portion of an actuator rod 34 that can move in the vertical direction with respect to the holding base 29 via a connecting member 35. In addition, in the illustrated example, the centering jig 30, the actuator rod 34, and the connecting member 35 are integrally manufactured, but they can also be manufactured separately.

[0064] In addition, the centering jig 30 has an inner diameter of the large-diameter portion 44 that can radially and non-rockingly fit into the guide portion 13 of the hub ring 22. However, the centering jig 30 can also be configured to have an inner diameter of the small-diameter portion 45 that can radially and non-rockingly fit into the guide portion 13 of the hub ring 22. Further, in a state where the centering jig 30 is moved to the lower end position inside the insertion hole 33, the axial distance between the upper end surface of the centering jig 30 and the flange contact surface 32 is larger than the axial dimension of the guide portion 13 of the hub ring 22.

[0065] (Method for manufacturing the hub unit bearing 1)

[0066] Next, a method for forming the pressing portion 26 using the swing pressing device 28 when manufacturing the hub unit bearing 1 will be described.

[0067] The forming operation of the pressing portion 26 is performed in a state where the hub unit bearing 1 before forming the pressing portion 26 is assembled. Therefore, the hub unit bearing 1 before forming the pressing portion 26 is pre-assembled.

[0068] The hub unit bearing 1 before forming the pressing portion 26 can be assembled in an appropriate order. For example, it can be assembled in the following order. First, around the inner raceway 11a on the outer side in the axial direction in the hub ring 22 (hub ring 22 having a cylindrical portion 27 at the inner end in the axial direction) before forming the pressing portion 26, the rolling elements 4a in the outer row in the axial direction are arranged in a state of being held by the outer cage 21a in the axial direction, and the outer ring 2 is arranged around the axial middle portion of the hub ring 22. Next, around the inner raceway 11b on the inner side in the axial direction in the inner ring 23, the rolling elements 4b in the inner row in the axial direction are arranged in a state of being held by the inner cage 21b in the axial direction. Then, the inner ring 23 is externally fitted to the fitting shaft portion 24 of the hub ring 22 before forming the pressing portion 26, and the outer end surface in the axial direction of the inner ring 23 is brought into contact with the stepped surface 25.

[0069] When forming the pressing portion 26 using the swing pressing device 28, first, the hub unit bearing 1 before forming the pressing portion 26 is set on the holding base 29.

[0070] Specifically, as Figure 2 shown, the die 31 is retracted upward, and the centering jig 30 is arranged in the upper part inside the insertion hole 33 of the holding base 29. Then, in this state, as Figure 2 shown, the guide portion 13 of the hub ring 22 is inserted into the inside of the insertion hole 33 of the holding base 29. At the same time, the large-diameter portion 44 of the guide portion 13 is radially and non-rockingly fitted inside the centering jig 30. Thereby, the central axis of the hub ring 22 is arranged coaxially with the reference axis C. Moreover, the outer end surface in the axial direction of the rotating flange 12 of the hub ring 22 is brought into contact with the flange contact surface 32 of the holding base 29.

[0071] Next, as Figure 2 → Figure 3 shown, while maintaining the state in which the central axis of the wheel hub ring 22 is coaxially arranged with the reference axis C, the centering jig 30 is retracted downward from the periphery of the guide portion 13. As a result, a state is formed in which a radial gap 37 exists in the entire circumferential range between the inner peripheral surface of the insertion hole 33 and the outer peripheral surface of the large-diameter portion 44 of the guide portion 13.

[0072] That is, in this example, at the start of the processing for forming the pressing portion 26 described below, the state in which the wheel hub ring 22 is coaxially arranged with the reference axis C is set in advance. At the same time, during the processing for forming the pressing portion 26 described below, based on the existence of the gap 37, the wheel hub ring 22 is enabled to move radially relative to the holding seat 29 in advance.

[0073] Next, the pressing process is started in this state. That is, as Figure 2 → Figure 3 shown, by moving the die 31 downward, while pressing the machining surface portion 36 of the die 31 against the cylindrical portion 27 of the wheel hub ring 22, the die 31 is rotated about the reference axis C, thereby machining the cylindrical portion 27 into the pressing portion 26. That is, a machining force that is directed downward in the vertical direction and outward in the radial direction is applied to a part of the circumferential direction of the cylindrical portion 27 from the machining surface portion 36 of the die 31. In addition, the position where this machining force is applied continuously changes in the circumferential direction of the cylindrical portion 27 as the die 31 rotates about the reference axis C. As a result, by plastically deforming the cylindrical portion 27 outward in the radial direction, the pressing portion 26 is formed.

[0074] In the manufacturing method of the wheel unit bearing 1 of this example as described above, during the processing for forming the pressing portion 26, based on the existence of the gap 37, the wheel hub ring 22 can move radially relative to the holding seat 29. Therefore, by such movement of the wheel hub ring 22, it is possible to reduce the deformation and / or vibration generated in the holding seat 29 constituting the swing pressing device 28, the support table (not shown) that supports the holding seat 29, and the like. That is, according to this example, it is possible to reduce the energy consumed other than forming the pressing portion 26 ( Figure 10 the lost energy E3), and correspondingly, it is possible to improve the processing efficiency of the pressing portion 26 ( Figure 10 the ratio (E2 / E1) of the output energy E2 to the input energy E1).

[0075] In addition, in this example, at the start of the process for forming the pressing portion 26, the hub ring 22 is arranged coaxially with the reference axis C. In other words, it is possible to sufficiently suppress the deviation in the radial position of the hub ring 22 at the start of the process for forming the pressing portion 26. Therefore, it is possible to sufficiently suppress the deviation in the quality characteristics obtained based on the formation of the pressing portion 26 (for example, the axial force applied to the inner ring 23 from the pressing portion 26, characteristics related to the amount of expansion of the inner ring 23 generated with the formation of the pressing portion 26, etc.).

[0076] (Method for setting the diameter difference δ)

[0077] Next, a method for setting the diameter difference δ (= D - d) (the size of the gap 37), which can improve the processing efficiency of the pressing portion 26, will be described.

[0078] First, according to the relationship with the hub unit bearing 1 to be manufactured, a plurality of holders 29 with different diameter differences δ (= D - d) are prepared. Then, for each of the prepared holders 29, the cylindrical portion 27 of the hub ring 22 is processed into the pressing portion 26 (the pressing process) using the swing pressing device 28 including the holder 29. Then, the total energy Et required for the die 31 to rotate about the reference axis C during this pressing process, specifically, during the period from the start to the end of the process for forming the pressing portion 26, and the total energy Ez required to press the die 31 against the axially inner end portion (cylindrical portion 27) of the hub ring 22 are obtained, and further, the sum thereof, i.e., the energy sum E (= Et + Ez), is obtained.

[0079] In this example, in order to obtain the total energy Et required for the die 31 to rotate about the reference axis C during the pressing process, the total rotation angle of the die 31 during the pressing process, i.e., the "total die rotation angle", and the torque for rotating the die 31 about the reference axis C, i.e., the "die rotation torque", are measured. Figure 4 FIG. (A) is a graph (hypothetical example) showing the relationship (curve f1) between the "total die rotation angle" and the "die rotation torque" measured in this way. And in this example, in this graph, the area of the region sandwiched between the curve f1 and the horizontal axis (the straight line representing "die rotation torque" = 0) is obtained as the total energy Et. That is, the above area (total energy Et) is obtained by integrating the "total die rotation angle" with respect to the "die rotation torque" (performing numerical calculation). In addition, the "total die rotation angle" can be measured using, for example, an encoder. Further, the "die rotation torque" can be measured based on, for example, the current value of the electric motor for rotating the die 31 about the reference axis C.

[0080] In addition, in this example, in order to obtain the total energy Ez required to press the mold 31 against the inner axial end of the wheel rim 22 during the pressing process, the relative displacement amount of the holding seat 29 and the mold 31 in the direction with respect to the reference axis C during the pressing process, that is, the "axial mold displacement amount", and the load for pressing the inner axial end of the mold 31 and the wheel rim 22 against each other in the direction of the reference axis C, that is, the "axial mold load", are measured. Figure 4 The (B) in Figure 4 is a line graph (hypothetical example) showing the relationship (curve f2) between the "axial mold displacement amount" and the "axial mold load" measured in this way. And, in this example, the area of the region sandwiched between the curve f2 and the horizontal axis (a straight line representing "axial mold load" = 0) in this line graph is obtained as the total energy Ez. That is, by integrating the "axial mold displacement amount" with respect to the "axial mold load" (performing numerical calculation), the above area (total energy Ez) is obtained. In addition, the "axial mold displacement amount" can be measured using a linear scale or the like, for example. Further, the "axial mold load" can be measured based on the hydraulic pressure in a hydraulic mechanism for moving the mold 31 in the axial direction, for example.

[0081] Next, using the energy sum E (= Et + Ez) obtained for each holding seat 29 with different diameter differences δ (= D - d) as described above, Figure 5 the relationship (curve f3) between the diameter difference δ (= D - d) and the energy sum E (= Et + Ez) as exemplified in Figure 5 is obtained.

[0082] In this relationship, if the diameter difference δ (= D - d) is gradually increased from 0, the energy sum E (= Et + Ez) will gradually decrease at the beginning, but will become substantially fixed from the middle. In the range where the energy sum E is substantially fixed, it is considered that the radial displacement amount of the wheel rim 22 during the pressing process is substantially fixed regardless of the value of the diameter difference δ (= D - d). In addition, even if the diameter difference δ (= D - d) is increased, the quality characteristics based on the formation of the pressing portion 26 (for example, the axial force applied to the inner ring 23 from the pressing portion 26, characteristics related to the expansion amount of the inner ring 23 generated with the formation of the pressing portion 26, etc.) will not deteriorate.

[0083] In addition, the energy for forming the pressing portion 26 ( Figure 10 the output energy E2) is substantially fixed. Therefore, the decrease in the energy sum E (= Et + Ez) ( Figure 10 the input energy E1) along with the increase in the diameter difference δ (= D - d) as described above indicates that the energy consumed other than forming the pressing portion 26 ( Figure 10 the loss energy E3) decreases, that is, the processing efficiency of the pressing portion 26 is improved.

[0084] Therefore, in order to improve the processing efficiency of the pressing portion 26, as long as it is used Figure 5Regarding the relationship, it is only necessary to set (determine) the diameter difference δ(=D - d) within the range where the energy sum E(=Et + Ez) is below the desired specified value. In this case, it is preferable that the diameter difference δ(=D - d) can be set within the range where the energy sum E(=Et + Ez) is substantially fixed.

[0085] In addition, the method of selecting the lower limit value δm of the diameter difference δ(=D - d) within the range where the energy sum E(=Et + Ez) is substantially fixed is arbitrary. For example, for the curve f3 representing the Figure 5 relationship, the constant S in the case where the curve represented by the following equation (1) having constants A and S can be fitted can be set as the lower limit value δm.

[0086] E = A×exp(-δ / S) -----(1)

[0087] Here, in equation (1), E is the variable representing the energy sum E(=Et + Ez), δ is the variable representing the diameter difference δ(=D - d), A is the value of the energy sum E(=Et + Ez) when the diameter difference δ(=D - d) is 0, and S is a constant with the same consideration method as the time constant.

[0088] Alternatively, for the curve f3 representing the Figure 5 relationship, a value larger than the parameter S in the case where the curve represented by the above equation (1) is fitted (for example, Figure 5 the lower limit value within the range of the diameter difference δ(=D - d) where the curve f3 appears to be substantially fixed) can also be selected as the lower limit value δm.

[0089] In addition, according to the experience of the present inventors, it has been confirmed that when processing for forming the pressing portion is performed by the above-mentioned conventional method, the amplitude in the horizontal direction of the support table of the holding base is about 0.5 mm. Therefore, considering such a situation, it is desirable to set the lower limit value δm to a value of 0.5 mm or more.

[0090] Alternatively, regarding the curve f3 representing the Figure 5 relationship, it is also possible to determine the diameter difference δ(=D - d) within the range where the change amount (decrease amount) of the energy sum E(=Et + Ez) with respect to the change amount (increase amount) of the diameter difference δ(=D - d) is below the specified value.

[0091] However, if the diameter difference δ(=D - d) is made too large, that is, if the inner diameter of the insertion hole 33 of the holding base 29 is made too large, the rotating flange 12 may be likely to deform in a manner of falling inward in the axial direction when processing for forming the pressing portion 26 is performed. Therefore, in order to prevent such a malfunction from occurring, it is desirable to set the diameter difference δ(=D - d) to 2 to 10 times or less of the lower limit value δm.

[0092] In addition, inFigure 2 and Figure 3 In the example shown in Figure 1 , the processing for forming the pressing portion 26 is performed in a state before the installation of the stud bolt 16 (see Figure 1 ) into the mounting hole 14 of the rotating flange 12. However, in the case of implementing the present invention, the processing for forming the pressing portion 26 can also be performed in a state where the stud bolt 16 is installed in the mounting hole 14 of the rotating flange 12. In this case, the shape of the holding base is set to a shape in which the stud bolt 16 does not collide during this processing (for example, a shape having an insertion hole for the stud bolt that can loosely insert a portion of the stud bolt 16 protruding axially outward from the axially outer side surface of the rotating flange 12).

[0093] [Second Example of the Embodiment]

[0094] Use Figure 6 and Figure 7 to describe the second example of the embodiment of the present invention.

[0095] In this example, the structure of the holding base 29a constituting the swing pressing device 28a and its peripheral portion is different from that in the first example of the embodiment. That is, in this example, the insertion hole 33a of the holding base 29a can be inserted (embedded) into the guide portion 13 of the hub ring 22 without radial play.

[0096] In addition, the holding base 29a is supported in such a manner that it can move in a direction orthogonal to the reference axis C. For this purpose, the swing pressing device 28a of this example includes a support table 40, a movable table 38, an X-direction linear guide 39, and a Y-direction linear guide 41. In addition, in this example, the reference axis C is the central axis of the insertion hole 33a formed in the holding base 29a in the neutral position before movement.

[0097] The support table 40 is disposed below the holding base 29a and is prevented from moving in a direction orthogonal to the reference axis C. The movable table 38 is disposed between the holding base 29a and the support table 40 in the vertical direction. In addition, the movable table 38 is supported on the upper side surface of the support table 40 via the X-direction linear guide 39. The X-direction linear guide 39 is a guiding device that can move the movable table 38 relative to the support table 40 in one direction orthogonal to the reference axis C, that is, the X direction. In addition, the holding base 29a is supported on the upper surface of the movable table 38 via the Y-direction linear guide 41. The Y-direction linear guide 41 is a guiding device that can move the holding base 29a relative to the movable table 38 in a direction orthogonal to the reference axis C and also orthogonal to the X direction, that is, the Y direction. Therefore, the holding base 29a is allowed to move in all directions orthogonal to the reference axis C relative to the support table 40 through the X-direction linear guide 39 and the Y-direction linear guide 41.

[0098] ​​Further, in a state where the movable stage 38 is disposed at the neutral position in the X direction and the holding base 29a is disposed at the neutral position in the Y direction, the central axis of the insertion hole 33a of the holding base 29a coincides with the reference axis C.

[0099] Further, an X-direction spring 42 is assembled between the movable stage 38 and a fixed portion (not shown). When the movable stage 38 moves in the X direction from the neutral position in the X direction, the X-direction spring 42 imparts an elastic force in a direction to return the movable stage 38 to the neutral position in the X direction. Further, a Y-direction spring 43 is assembled between the holding base 29a and a fixed portion (not shown). When the holding base 29a moves in the Y direction from the neutral position in the Y direction, the Y-direction spring 43 imparts an elastic force in a direction to return the holding base 29a to the neutral position in the Y direction. Therefore, in a state where no external force in the X direction acts on the movable stage 38 and no external force in the Y direction acts on the holding base 29a (for example, a state before the start of processing for forming the pressing portion 26 (refer to Figure 1 )) described later), the movable stage 38 is disposed at the neutral position in the X direction, and the holding base 29a is disposed at the neutral position in the Y direction. As a result, the central axis of the insertion hole 33a of the holding base 29a coincides with the reference axis C. That is, the X-direction spring 42 and the Y-direction spring 43 have a function of applying a force to the holding base 29a in a direction in which the central axis of the insertion hole 33a and the reference axis C coincide when the holding base 29a moves and the central axis of the insertion hole 33a and the reference axis C become non-coincident.

[0100] Further, in this example, when forming the pressing portion 26 using the swing pressing device 28a as described later, the elastic forces of the X-direction spring 42 and the Y-direction spring 43 are made sufficiently small (for example, set to 1 / 10 or less of the processing force) compared to the processing force acting on the wheel rim 22 from the mold 31 and directed radially outward.

[0101] When forming the pressing portion 26 using the swing pressing device 28a, first, as Figure 6 shown, by inserting the guide portion 13 of the wheel rim 22 into the insertion hole 33a of the holding base 29a without radial play, the central axis of the wheel rim 22 is coaxially disposed with the reference axis C. At the same time, the axially outer surface of the rotary flange 12 of the wheel rim 22 is brought into contact with the flange contact surface 32 of the holding base 29a. Then, in this state, in the same manner as in the first example of the embodiment, the cylindrical portion 27 is processed into the pressing portion 26 using the mold 31.

[0102] In the manufacturing method of the hub unit bearing 1 of the present example as described above, in the process of forming the pressing portion 26, due to the presence of the X-direction linear guide 39 and the Y-direction linear guide 41, the hub ring 22 can move radially relative to the reference axis C. And thus, in the process of forming the pressing portion 26, the hub ring 22 moves radially relative to the reference axis C, whereby deformation and / or vibration of the holding seat 29a constituting the swing pressing device 28a and the support table 40 supporting the holding seat 29a can be reduced. In addition, in the present example, as the hub ring 22 moves radially relative to the reference axis C, the amount of elastic deformation of the X-direction spring 42 and the Y-direction spring 43 changes, but since the elastic forces of the X-direction spring 42 and the Y-direction spring 43 are small enough, the energy for changing the amount of elastic deformation of the X-direction spring 42 and the Y-direction spring 43 can be sufficiently suppressed. Therefore, in the present example, the energy consumed other than forming the pressing portion 26 ( Figure 10 the lost energy E3) can be reduced, and correspondingly, the processing efficiency of the pressing portion 26 ( Figure 10 the ratio (E2 / E1) of the output energy E2 to the input energy E1) can be improved.

[0103] In addition, in the present example, at the start of the process of forming the pressing portion 26, the hub ring 22 is coaxially arranged with the reference axis C. In other words, the deviation of the radial position of the hub ring 22 at the start of the process of forming the pressing portion 26 can be sufficiently suppressed. Therefore, the deviation of the quality characteristics (such as the axial force applied to the inner ring 23 from the pressing portion 26, the characteristics related to the amount of expansion of the inner ring 23 generated with the formation of the pressing portion 26, etc.) obtained based on the formation of the pressing portion 26 can be sufficiently suppressed.

[0104] Other structures and effects are the same as those of the first example of the embodiment.

[0105] Furthermore, the present invention is not limited to the hub unit bearing for the driven wheel, and the hub unit bearing for the driving wheel can also be set as the manufacturing object. In addition, the present invention is not limited to the hub unit bearing using tapered rollers as rolling elements, and the hub unit bearing using balls as rolling elements can also be set as the manufacturing object. In addition, the present invention is not limited to the hub unit bearing in which the axially outer inner ring raceway is directly formed on the outer peripheral surface of the axial intermediate portion of the hub ring, and the hub unit bearing in which the axially outer inner ring raceway is formed on the outer peripheral surface of the second inner ring as another component externally fitted to the axial intermediate portion of the hub ring can also be set as the manufacturing object.

[0106] Explanation of reference numerals

[0107] 1: Wheel hub unit bearing 2: Outer ring 3: Wheel hub 4a, 4b: Rolling elements 5a, 5b: Outer ring raceways 6: Stationary flange 7: Support hole 8: Steering knuckle 9: Through hole 10: Bolt 11a, 11b: Inner ring raceways 12: Rotating flange 13: Guide portion 14: Mounting hole 15: Rotating body for braking 16: Stud bolt 17: Through hole 18: Wheel 19: Through hole 20: Nut 21a, 21b: Cage 22: Wheel hub ring 23: Inner ring 24: Fitting shaft portion 25: Step surface 26: Pressing portion 27: Cylindrical portion 28, 28a: Swing pressing device 29, 29a: Retaining seat 30: Centering jig 31: Die 32: Flange receiving surface 33, 33a: Insertion hole 34: Actuator rod 35: Connecting member 36: Machined surface portion 37: Clearance 38: Movable table 39: Linear guide in X direction 40: Support table 41: Linear guide in Y direction 42: Spring in X direction 43: Spring in Y direction 44: Large diameter portion 45: Small diameter portion 100: Wheel hub unit bearing 101: Outer ring 102: Wheel hub 103a, 103b: Rolling elements 104a, 104b: Outer ring raceways 105: Stationary flange 106a, 106b: Inner ring raceways 107: Rotating flange 108: Guide portion 109: Wheel hub ring 110: Inner ring 111: Fitting shaft portion 112: Step surface 113: Pressing portion 114: Swing pressing device 115: Die 116: Retaining seat 117: Flange receiving surface 118: Insertion hole.

Claims

1. A manufacturing method of a wheel hub unit bearing, wherein, the wheel hub unit bearing includes an outer ring, a wheel hub, and rolling elements disposed between the outer ring and the wheel hub, the wheel hub has an inner ring, a wheel hub ring, and a pressing portion for integrally connecting the inner ring and the wheel hub ring, the manufacturing method includes: a step of preparing a holder; a step of holding the wheel hub ring combined with the inner ring onto the holder along a reference axis; and a step of forming the pressing portion using a die in a state where (i) the wheel hub ring is movable relative to the holder in a direction orthogonal to the reference axis, or (ii) the holder holding the wheel hub ring is movable in a direction orthogonal to the reference axis, the wheel hub ring has a shaft portion provided with a raceway for the rolling elements and a guiding portion provided at an axial end of the shaft portion, the holder has an insertion hole having an inner diameter larger than an outer diameter of the guiding portion of the wheel hub ring, in the holding step, it includes: a step of inserting the guiding portion of the wheel hub ring into the insertion hole of the holder and holding the wheel hub ring combined with the inner ring onto the holder; a step of fitting a centering jig to the guiding portion of the wheel hub ring to align a central axis of the wheel hub ring with the reference axis; and a step of removing the centering jig from the wheel hub ring after the alignment, in the step of forming the pressing portion, it includes a step of forming the pressing portion using the die in a state where the wheel hub ring after removing the centering jig is movable relative to the holder in a direction orthogonal to the reference axis.

2. The manufacturing method of a wheel hub unit bearing according to claim 1, wherein, the pressing step is started in a state where the central axis of the wheel hub ring is coaxially arranged with the reference axis.

3. The manufacturing method of a wheel hub unit bearing according to claim 1, wherein, a difference in diameter, i.e., a difference between the inner diameter of the insertion hole and the outer diameter of the guiding portion, is determined based on a sum of total energy required for rotating the die about the reference axis and total energy required for pressing the die against the wheel hub ring, i.e., an energy sum, in the step of forming the pressing portion.

4. The manufacturing method of a wheel hub unit bearing according to claim 3, wherein, the difference in diameter is determined within a range where the energy sum is equal to or less than a specified value.

5. The manufacturing method of a wheel hub unit bearing according to claim 3, wherein, the difference in diameter is determined within a range where the energy sum is substantially fixed.

6. The manufacturing method of a wheel hub unit bearing according to claim 3, wherein, the difference in diameter is determined within a range where a change amount of the energy sum with respect to a change amount of the difference in diameter is equal to or less than a specified value.

7. The manufacturing method of a wheel hub unit bearing according to any one of claims 3 to 6, wherein, the total energy required for rotating the die about the reference axis in the step of forming the pressing portion is obtained by integrating a torque for rotating the die about the reference axis with respect to a rotation angle of the die about the reference axis.

8. The manufacturing method of a hub unit bearing according to any one of claims 3 to 6, wherein, by integrating the load for pressing the die and the hub ring against each other in the direction of the reference axis with the relative movement amount of the holding seat and the die in the direction of the reference axis, the total energy required to press the die against the hub ring in the process of forming the pressing portion is obtained.

9. A manufacturing method of a vehicle, wherein the vehicle is equipped with a hub unit bearing, and in the manufacturing method of the vehicle, the hub unit bearing is manufactured by the manufacturing method of the hub unit bearing according to any one of claims 1 to 8.

10. A swing pressing device for manufacturing a hub unit bearing, wherein, the hub unit bearing includes an outer ring, a hub, and rolling elements disposed between the outer ring and the hub, the hub has an inner ring, a hub ring, and a pressing portion for binding the inner ring and the hub ring to each other, the hub ring has a shaft portion provided with a raceway for the rolling elements and a guiding portion provided at the shaft end of the shaft portion, the swing pressing device includes: a reference axis; a die; a centering jig; and a holding seat that holds the hub ring combined with the inner ring during the pressing process of forming the pressing portion using the die, the holding seat has an insertion hole with an inner diameter larger than the outer diameter of the guiding portion of the hub ring, which can switch between a first state and a second state. In the first state, the centering jig is fitted into the guiding portion of the hub ring inserted into the insertion hole of the holding seat, and the central axis of the hub ring is aligned with the reference axis. In the second state, the centering jig is removed from the hub ring, and the hub ring can move relative to the holding seat in a direction orthogonal to the reference axis.

11. A swing pressing device for manufacturing a hub unit bearing, wherein, the hub unit bearing includes an outer ring, a hub, and rolling elements disposed between the outer ring and the hub, the hub has an inner ring, a hub ring, and a pressing portion for binding the inner ring and the hub ring to each other, the swing pressing device includes: a reference axis; a die; and a holding seat that holds the hub ring combined with the inner ring and can move in a direction orthogonal to the reference axis while holding the hub ring during the pressing process of forming the pressing portion using the die.

12. The swing pressing device according to claim 11, wherein, it further includes: a support table that is blocked from moving in a direction orthogonal to the reference axis; a movable table; an X-direction linear guide that supports the movable table in a manner that allows movement in one direction orthogonal to the reference axis, namely the X direction; and a Y-direction linear guide that supports the holding seat relative to the movable table in a manner that allows movement in a Y direction orthogonal to both the reference axis and the X direction.

13. The swing pressing device according to claim 11 or 12, wherein, it further includes a spring that applies a force to the holding seat to align the central axis of the hub ring with the reference axis.

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