Crimping joining method, method for manufacturing hub unit bearing, method for manufacturing vehicle, method for manufacturing machine device, and crimping device

Abstract

A step for forming the crimped part includes deforming the first member (17a) by using a first relative rotation around a reference axis between a first pressing die (39) and a workpiece (90), and further deforming the first member (17a) by using a second relative rotation around a reference axis between a second pressing die (39) and the workpiece (90). In the first relative rotation, the center axis of the first pressing die (39) is inclined with respect to the reference axis at a first inclination angle (θ1), and in the second relative rotation, the center axis of the second pressing die (39) is inclined with respect to the reference axis at a second inclination angle (θ2) different from the first inclination angle.

Description

Crimping connection method, manufacturing method of hub unit bearing, manufacturing method of vehicle, manufacturing method of mechanical device, and crimping processing device

[0001] The present invention relates to a crimping method, a method for manufacturing a hub unit bearing, a method for manufacturing a vehicle, a method for manufacturing a mechanical device, and a crimping device. This application claims priority to Japanese Patent Application No. 2024-061434, filed April 5, 2024, the contents of which are incorporated herein by reference.

[0002] A hub unit bearing is known as an example of a caulked assembly in which a first member and a second member are axially assembled. The hub unit bearing rotatably supports the wheels and braking rotors of an automobile relative to a suspension system. The hub unit bearing includes an outer ring having a double-row outer ring raceway on its inner peripheral surface, a hub having a double-row inner ring raceway on its outer peripheral surface, and a plurality of rolling elements disposed freely rollable between the double-row outer ring raceway and the double-row inner ring raceway.

[0003] The hub includes an inner ring and a hub body (hub wheel). The inner ring is press-fit onto a mating shaft portion provided on the hub body's axially inner side (the inner side in the vehicle width direction when the hub unit bearing is assembled to the vehicle), with its axially outer end face (the outer side in the vehicle width direction when the hub unit bearing is assembled to the vehicle) abutting against a stepped surface provided on the hub body's axially middle portion and facing axially inward. In this state, a cylindrical portion of the mating shaft portion that protrudes axially inward beyond the axially inner end face of the inner ring is plastically deformed radially outward to form a crimped portion, which presses against the axially inner end face of the inner ring. This fixes the inner ring to the hub body and applies a preload to the rolling elements.

[0004] JP 2015-77616 A describes an oscillation clamping method for joining a hub body and an inner ring, in which a stamping die (metal mold) supported so as to be rotatable about a central axis inclined with respect to a reference axis arranged coaxially with the central axis of the hub body is rotated about the reference axis while pressing its tip against a cylindrical portion, thereby plastically deforming the cylindrical portion radially outward to form a crimped portion. In the oscillation clamping method described in JP 2015-77616 A, the oscillation angle, which is the inclination angle of the central axis of the stamping die with respect to the reference axis, is set to be between 15° and 30°, thereby keeping the processing load low.

[0005] JP 2015-77616 A

[0006] In the swing clamping method described in JP 2015-77616 A, the swing angle is set to a relatively large value of between 15° and 30°. As a result, in the early stages of processing, the radial force applied to the hub body from the pressing die can cause the hub body to vibrate (vibrate), potentially reducing processing accuracy.

[0007] Setting the rocking angle to a relatively small value of about 5° can prevent vibration of the hub body in the early stages of processing, but the contact area between the hub body and the die increases, necessitating a larger processing load, which can increase the amount of radial outward expansion of the inner ring, potentially creating problems such as the generation of circumferential tensile stress (hoop stress) in the inner ring.

[0008] This problem tends to become more pronounced when, after the crimped portion is formed, a face spline is formed on the axial end surface of the crimped portion by forging, whereby recesses and protrusions are arranged alternately in the circumferential direction, or when the axial thickness of the portion of the inner ring that is axially inwardly spaced from the inner ring raceway is small.

[0009] An object of aspects of the present invention is to provide a crimping connection method, a method for manufacturing a hub unit bearing, a method for manufacturing a vehicle, a method for manufacturing a mechanical device, and a crimping processing device that are advantageous for reducing manufacturing costs and / or improving product quality.

[0010] A crimping method according to one aspect of the present invention includes the steps of: setting a workpiece, in which a first member and a second member are axially assembled, along a reference axis; and forming a crimped portion in the first member, the step including: deforming the first member by a first relative rotation about the reference axis between a first pressing die and the workpiece; and further deforming the first member by a second relative rotation about the reference axis between a second pressing die and the workpiece. During the first relative rotation, a central axis of the first pressing die is inclined with respect to the reference axis at a first tilt angle, and during the second relative rotation, a central axis of the second pressing die is inclined with respect to the reference axis at a second tilt angle different from the first tilt angle.

[0011] In another aspect of the present invention, a method for manufacturing a vehicle includes manufacturing a hub unit bearing using the above-described manufacturing method, and assembling a vehicle using the hub unit bearing.

[0012] In another aspect of the invention, a method for manufacturing a mechanical device comprises manufacturing a crimped assembly using the crimping method described above, and assembling a mechanical device using the crimped assembly.

[0013] In another aspect of the present invention, a crimping apparatus includes a reference axis, a holder for supporting a workpiece, a stamping die having a central axis, a first mechanism for performing relative rotation between the workpiece and the stamping die with the central axis tilted relative to the reference axis around the reference axis, and a second mechanism for changing the tilt angle of the central axis relative to the reference axis. During the first relative rotation, the central axis of the stamping die is tilted relative to the reference axis by a first tilt angle. During the second relative rotation, the central axis of the stamping die is tilted relative to the reference axis by a second tilt angle different from the first tilt angle.

[0014] The aspects of the present invention are advantageous in reducing manufacturing costs and / or improving product quality.

[0015] FIG. 1 is a cross-sectional view showing an example of a wheel drive unit equipped with a hub unit bearing. FIG. 2 is a cross-sectional view showing a crimping device. Part (A) of FIG. 3 is a cross-sectional view showing a portion of the crimping device, and part (B) is a view showing the same portion as part (A) with a different rocking angle. Parts (A) and (B) of FIG. 4 are views for explaining a mechanism for changing the rocking angle, part (a) is a view seen from the axial direction, and part (b) is a perspective view. Parts (A) to (E) of FIG. 5 are cross-sectional schematic views showing the crimping method in the order of steps. FIG. 6 is a partial schematic view of a vehicle equipped with a hub unit bearing.

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0017] In one embodiment, the crimping method includes fitting a cylindrical metal second member onto a metal first member having a cylindrical portion at one axial end. Then, the axial end at one side of the cylindrical portion is plastically deformed to form a crimped portion. The first and second members are joined by preventing the second member from displacing axially toward one side relative to the first member. The crimping method and crimping apparatus are widely applicable to the manufacture of machinery, vehicles, or components thereof, including two metal members joined by a crimped portion.

[0018] In one embodiment, the crimping method and crimping device are applied to the manufacture of a hub unit bearing that constitutes a vehicle. In the following description, although the detailed shapes of some parts differ between the drawings, parts with the same reference numerals have the same content and function.

[0019] The present disclosure can be applied to both the manufacture of hub unit bearings for driving wheels in which a central hole passing through the center of the hub in the axial direction is provided, and the manufacture of hub unit bearings for driven wheels in which the hub is configured as a solid core.

[0020] Furthermore, the present disclosure can be applied to both the manufacture of a hub unit bearing having a face spline on the axial end surface of the crimped portion and the manufacture of a hub unit bearing having no face spline.

[0021] Furthermore, the present disclosure can be applied to the manufacture of both so-called 2.5th generation hub unit bearings and so-called third generation hub unit bearings. The hub of a 2.5th generation hub unit bearing includes a shaft member and two inner rings, each having an inner ring raceway on its outer peripheral surface, and fitted onto the shaft member. In a 2.5th generation hub unit bearing, the hub body is composed of the shaft member and the axially outermost inner ring of the two inner rings. The hub of a third generation hub unit bearing includes an inner ring having, on its outer peripheral surface, at least the axially innermost inner ring raceway of a plurality of inner ring raceways, and a hub body having at least the axially outermost inner ring raceway of the plurality of inner ring raceways, and a fitting shaft portion onto which the inner ring is fitted.

[0022] In one example, the present disclosure is applied to the manufacture of so-called third generation hub unit bearings for drive wheels, which have face splines on the axial end faces of the crimped portions.

[0023] 1 shows a wheel drive unit 1 including a hub unit bearing 2. The wheel drive unit 1 includes the hub unit bearing 2 and a constant velocity joint 3.

[0024] In the following description, unless otherwise specified, the axial direction, radial direction, and circumferential direction with respect to the wheel drive unit 1 refer to the axial direction, radial direction, and circumferential direction, respectively, of the hub 5 of the hub unit bearing 2. The axial direction, radial direction, and circumferential direction of the hub 5 correspond to the axial direction, radial direction, and circumferential direction, respectively, of the outer ring 4 of the hub unit bearing 2, and also correspond to the axial direction, radial direction, and circumferential direction, respectively, of the constant velocity joint 3. Furthermore, the outer axial direction refers to the outer side in the width direction of the vehicle body when the wheel drive unit 1 is assembled to the vehicle, and the inner axial direction refers to the inner side in the width direction of the vehicle body when the wheel drive unit 1 is assembled to the vehicle.

[0025] <Structure of Hub Unit Bearing> In one example, the hub unit bearing 2 includes an outer ring 4, a hub 5, and a plurality of rolling elements 6a, 6b.

[0026] The outer ring 4 has a hollow shape and has a plurality of outer ring raceways 7a, 7b on its inner peripheral surface.

[0027] In this example, the plurality of outer ring raceways 7a, 7b are configured as double-row (two-row) outer ring raceways 7a, 7b.

[0028] Each of the outer ring raceways 7a, 7b has a generatrix shape that corresponds to the shape of the multiple rolling elements 6a, 6b. When the multiple rolling elements 6a, 6b are balls, each of the outer ring raceways 7a, 7b has an arc-shaped generatrix shape. When the multiple rolling elements 6a, 6b are tapered rollers, each of the outer ring raceways 7a, 7b has a linear generatrix shape that is inclined with respect to the central axis of the outer ring 4.

[0029] In the hub unit bearing 2 of this example, the plurality of rolling elements 6a, 6b are made up of balls, and therefore, each of the outer ring raceways 7a, 7b has a generatrix shape that is an arc.

[0030] The outer ring 4 has a stationary flange 8 that protrudes radially outward at an axially intermediate portion. The stationary flange 8 has flange-side support holes 9 that penetrate the outer ring 4 in the axial direction at a plurality of circumferential positions at the radially intermediate portion.

[0031] The outer ring 4 is supported and fixed to the knuckle by inserting a support bolt (not shown) into one of the flange side support holes 9 and the knuckle side support hole provided in the knuckle of the suspension device and screwing it into the other support hole.

[0032] The hub 5 is disposed radially inside the outer ring 4 and coaxially with the outer ring 4. The hub 5 has a plurality of inner ring raceways 10a, 10b on its outer peripheral surface.

[0033] In this example, the plurality of inner ring raceways 10a, 10b are configured as double rows (two rows) of inner ring raceways 10a, 10b.

[0034] Each of the inner ring raceways 10a, 10b has a generatrix shape that corresponds to the shape of the multiple rolling elements 6a, 6b. When the multiple rolling elements 6a, 6b are balls, each of the inner ring raceways 10a, 10b has an arc-shaped generatrix shape. When the multiple rolling elements 6a, 6b are tapered rollers, each of the inner ring raceways 10a, 10b has a linear generatrix shape that is inclined with respect to the central axis of the hub 5.

[0035] In the hub unit bearing 2 of this example, the plurality of rolling elements 6a, 6b are made up of balls, and therefore, each of the inner ring raceways 10a, 10b has a generatrix shape of an arc.

[0036] The hub 5 further has a center hole 11 and a hub-side face spline 12 .

[0037] The central hole 11 is provided so as to pass through the center of the hub 5 in the axial direction.

[0038] The hub-side face spline 12 is provided on the axially inner end surface of the hub 5, and is configured by alternately arranging recesses and protrusions in the circumferential direction. Specifically, the hub-side face spline 12 is provided on the axially inner end surface of a crimped portion 19 provided on the axially inner end of the hub body 17. The hub-side face spline 12 is also configured by arranging a plurality of teeth (protrusions) that protrude axially inward at equal intervals in the circumferential direction. The individual teeth that make up the hub-side face spline 12 are arranged radially.

[0039] In this example, the hub 5 has a rotating flange 13 that protrudes radially outward at a portion that protrudes axially outward beyond the outer ring 4, and also has a cylindrical pilot portion 14 at the axially outer end.

[0040] The rotary flange 13 has mounting holes 15 penetrating in the axial direction at a plurality of circumferential positions in a radially intermediate portion thereof. Each of the mounting holes 15 is configured as a press-fit hole or a screw hole.

[0041] When each mounting hole 15 is configured as a press-fit hole, a stud is press-fit into each mounting hole 15 from the axially inner side. The pilot portion 14 is inserted into a central hole provided at the center of each braking rotating body such as a brake disc and a wheel of a vehicle. Studs are also inserted into through-holes provided at multiple locations circumferentially in the radially middle portion of each rotating body. Hub nuts are threaded onto the tips of the studs, thereby connecting and fixing the wheel or the like to the rotating flange 13.

[0042] When each of the mounting holes 15 is configured as a threaded hole, the pilot portion 14 is inserted into a central hole provided at the center of the braking rotating body such as a brake disc and the wheel of the vehicle. Hub bolts are inserted into through holes provided at multiple locations circumferentially in the radially middle portion of each of the braking rotating body and the wheel, and are screwed into the mounting holes 15 from the outside in the axial direction, thereby connecting and fixing the wheel to the rotating flange 13.

[0043] The hub 5 includes an inner ring 16 and a hub body 17 .

[0044] The inner ring 16 is cylindrical and made of hard metal such as bearing steel. Of the multiple inner ring raceways 10 a, 10 b, at least the axially innermost inner ring raceway 10 b is located on the outer peripheral surface of the inner ring 16. In this example, the inner ring 16 has the axially innermost inner ring raceway 10 b of the double-row inner ring raceways 10 a, 10 b located in an axially intermediate portion of the outer peripheral surface.

[0045] The hub body 17 is made of a hard metal such as medium carbon steel. The hub body 17 has, on its outer circumferential surface, at least the axially innermost inner ring raceway 10b of the multiple inner ring raceways 10a, 10b, a fitting shaft portion 18 onto which the inner ring 16 is fitted, and a crimping portion 19 provided at the axially inner end portion and pressing against the axially inner end face of the inner ring 16.

[0046] In this example, the hub body 17 has, at the axially intermediate portion of its outer peripheral surface, the inner ring raceway 10a, which is on the outer side in the axial direction, of the double row inner ring raceways 10a, 10b.

[0047] The fitting shaft portion 18 is provided at a portion located axially more inward than the axially outer inner ring raceway 10a, and has a cylindrical outer peripheral surface whose outer diameter does not change in the axial direction. A portion of the outer peripheral surface of the hub body 17 adjacent to the axially inner side of the axially outer inner ring raceway 10a is connected to the outer peripheral surface of the fitting shaft portion 18 by a stepped surface 20 facing axially inward.

[0048] The crimped portion 19 extends radially outward from the axially inner end of the fitting shaft portion 18. The hub-side face spline 12 is provided on the axially inner end surface of the crimped portion 19.

[0049] In this example, the hub body 17 has a rotating flange 13 at a portion located axially outward of the axially outer inner ring raceway 10a, and also has a pilot portion 14 at the axially outer end.

[0050] The inner ring 16 is fitted onto the fitting shaft portion 18 of the hub body 17, and is sandwiched from both axial sides between the stepped surface 20 and the crimped portion 19 of the hub body 17. In this way, the inner ring 16 and the hub body 17 are joined to form the hub 5, and a preload is applied to the rolling elements 6a, 6b.

[0051] The plurality of rolling elements 6a, 6b are arranged in rows between the plurality of outer ring raceways 7a, 7b and the plurality of inner ring raceways 10a, 10b so as to be rollable, and are preloaded.

[0052] Each of the rolling elements 6a and 6b is made of a hard metal such as bearing steel or ceramics.

[0053] Each of the rolling elements 6a, 6b is made up of a ball or a tapered roller. In this example, each of the rolling elements 6a, 6b is made up of a ball.

[0054] The rolling elements 6a and 6b are arranged at equal intervals in the circumferential direction using cages 21a and 21b each having an annular shape.

[0055] The hub unit bearing 2 of this example has an equal diameter PCD type structure in which the pitch circle diameter of the rolling elements 6 a in the axially outer row is equal to the pitch circle diameter of the rolling elements 6 b in the axially inner row. In another example, the target may be a different diameter PCD type hub unit bearing in which the pitch circle diameter of the rolling elements in the axially outer row is larger or smaller than the pitch circle diameter of the rolling elements in the axially inner row.

[0056] <Structure of Constant Velocity Joint> The constant velocity joint includes a joint outer ring 22 , a joint inner ring 23 , and a plurality of balls 24 .

[0057] The joint outer ring 22 has, on its axially outer surface, a joint side face spline 25 that engages with the hub side face spline 12 of the hub 5 .

[0058] The joint outer ring 22 has a mouth portion 26 that is generally bowl-shaped, and a cylindrical portion 27 .

[0059] The mouth portion 26 has a substantially cylindrical peripheral wall portion 28 and a substantially hollow circular side wall portion 29 that is bent radially inward from the axially outer end of the peripheral wall portion 28 .

[0060] The inner peripheral surface of the peripheral wall portion 28 is configured as a partially spherical concave surface. The peripheral wall portion 28 has outer diameter side engagement grooves 30 extending in the axial direction at multiple locations in the circumferential direction of the inner peripheral surface.

[0061] The side wall portion 29 has a joint-side face spline 25 at a radially intermediate portion of the axially outer surface, in which recesses and protrusions are alternately arranged in the circumferential direction.

[0062] The cylindrical portion 27 is bent axially outward from the radially inner end of the side wall portion 29. The cylindrical portion 27 has a female thread portion 31 on its inner circumferential surface.

[0063] The joint inner ring 23 has a partially convex spherical outer peripheral surface, and has inner diameter side engagement grooves 32 extending in the axial direction at multiple locations around the circumference of the outer peripheral surface. The joint inner ring 23 also has a spline hole 33 that penetrates in the axial direction at its center. A spline shaft portion provided at the tip of a drive shaft (not shown) is spline-engaged with the spline hole 33.

[0064] Each ball 24 is disposed between the outer diameter side engagement groove 30 and the inner diameter side engagement groove 32 so as to be able to roll along the outer diameter side engagement groove 30 and the inner diameter side engagement groove 32 .

[0065] The hub 5 of the hub unit bearing 2 and the joint outer ring 22 of the constant velocity joint 3 are connected and fixed by engaging the hub-side face spline 12 with the joint-side face spline 25, threading the shank 35 of a bolt 34 inserted into the central hole 11 from the outside in the axial direction into the female thread portion 31, and clamping the hub 5 from both axial sides between the head 36 of the bolt 34 and the joint outer ring 22.

[0066] [Method of Manufacturing Hub Unit Bearing] When manufacturing the hub unit bearing 2, as shown in Figure 2, the outer ring 4 and multiple rolling elements 6a, 6b are arranged around the hub body 17a before the crimped portion 19a is formed. The hub body 17a before the crimped portion 19a is formed has a cylindrical portion 37 at its axially inner end (first end) adjacent to the axially inner side of the fitting shaft portion 18. The cylindrical portion 37 has an outer diameter that is equal to the outer diameter of the fitting shaft portion 18 and does not change in the axial direction. In other words, the outer peripheral surface of the fitting shaft portion 18 and the outer peripheral surface of the cylindrical portion 37 are formed by a single cylindrical surface.

[0067] The procedure for arranging the outer ring 4 and the plurality of rolling elements 6a, 6b around the hub body 17a is not particularly limited, and any procedure can be used as long as no contradiction occurs.

[0068] For example, first, multiple rolling elements 6a, 6b are inserted into pockets of two cages 21a, 21b, and the multiple rolling elements 6a, 6b are held in rows by the respective cages 21a, 21b. Next, the rows of rolling elements 6a, 6b held by the two cages 21a, 21b are held radially inside the outer ring raceways 7a, 7b of the outer ring 4. Next, the hub body 17a is inserted from the outside in the axial direction, radially inside the combined outer ring 4, multiple rolling elements 6a, 6b, and cages 21a, 21b. After that, the inner ring 16 is fitted onto the mating shaft portion 18 of the hub body 17a. In other words, the inner ring 16 is inserted between the axially inner row of rolling elements 6b and the mating shaft portion 18. The cylindrical portion 37 of the hub body 17a is plastically deformed radially outward to form the crimped portion 19, thereby joining the inner ring 16 and the hub body 17. In this way, the hub 5 is formed, and the hub unit bearing 2 is obtained.

[0069] In this example, the cylindrical portion 37 of the hub body 17a is plastically deformed radially outward to form a crimped portion 19, thereby joining the inner ring 16 and the hub body 17 (17a). In this example, the hub body 17 (17a) corresponds to the first member, and the inner ring 16 corresponds to the second member. Additionally, the axially inner side of the hub unit bearing 2 corresponds to one axial side, and the axially outer side of the hub unit bearing 2 corresponds to the other axial side.

[0070] In one embodiment, the crimping method joins the inner ring 16 and the hub body 17 (17a). First, an outer fitting process is performed in which the inner ring 16, which is the second member, is fitted onto the mating shaft portion 18 of the hub body 17a, which is the first member before the crimped portion 19a is formed. In this example, the outer ring 4 and multiple rolling elements 6a, 6b are arranged around the hub body 17a, and then the inner ring 16 is inserted between the axially inner row of rolling elements 6b and the mating shaft portion 18. A workpiece (object to be machined) 90, in which the hub body (first member) 17 (17a) and the inner ring (second member) 16 are axially assembled, is set along the reference axis C.

[0071] Next, a first forming step is performed to plastically deform the cylindrical portion 37. In the first forming step, a first pressing die 39, which is supported so as to be rotatable about a first rotation axis R that is its central axis, rotates the first rotation axis R at a predetermined first angle (first inclination angle) θ with respect to a reference axis (central axis) C of the hub body 17a. １ The first pressing die 39 is pressed against the cylindrical portion 37 in an inclined state while rotating about the reference axis C of the hub body 17a. In the first forming step, a portion of the hub body 17a (cylindrical portion 37) is plastically deformed using a first relative rotation about the reference axis C between the first pressing die 39 and the workpiece 90 (hub body 17a). During the first relative rotation, the central axis of the first pressing die 39 is inclined with respect to the reference axis C at a first inclination angle.

[0072] After the first molding step, a second molding step is carried out to further plastically deform the cylindrical portion 37. In the second molding step, a second pressing die 39, which is supported so as to be rotatable about a second rotation axis R as its central axis, rotates the second rotation axis R at a first angle θ with respect to a reference axis C of the hub body 17a. １ A predetermined second angle (second tilt angle) θ ２ The second mold 39 is pressed against the cylindrical portion 37 in an inclined state and rotates around the reference axis C of the hub body 17a. In the second forming step, a part of the hub body 17a (cylindrical portion 37) is further plastically deformed by a second relative rotation about the reference axis C between the second mold 39 and the workpiece 90 (hub body 17a). In the second relative rotation, the first inclination angle θ １ A second tilt angle θ different from ２The central axis of the second pressing die 39 is inclined with respect to the reference axis C. ２ is θ １ is larger than (θ ２ >θ １ The first and second molding steps form a crimped portion 19 that presses the axially inner end face of the inner ring 16 .

[0073] In this example, the same pressing die 39 is used as the first pressing die and the second pressing die. The first molding step and the second molding step are performed using the same caulking device 38.

[0074] In another example, different first and second molds (different molds) can be used, in which case the shapes of the first and second molds can be substantially the same as each other or can be different from each other.

[0075] <Structure of the Crimping Device> Next, the crimping device 38 will be described with reference to Figures 2 to 4. The crimping device 38 includes a press die 39, a press die support mechanism 40, a spindle drive mechanism (first mechanism) 41, and an inclination adjustment mechanism (swing angle change actuator, second mechanism) 47.

[0076] The press die 39 is a member that is pressed against the cylindrical portion 37 of the hub body 17a before the crimped portion 19 is formed, and plastically deforms the cylindrical portion 37 to form the crimped portion 19. The press die 39 is supported by a press die support mechanism 40 so that the swing angle θ, which is the inclination angle of the rotation axis R, which is the central axis of the press die 39, with respect to the reference axis C, can be adjusted, and so that the press die 39 can rotate about the rotation axis R.

[0077] The reference axis C is an axis that is arranged coaxially with the hub unit bearing 2 (hub 5), which is the workpiece. The extension direction of the reference axis C is not particularly limited, and can be any direction, such as the vertical direction (up and down direction) or the horizontal direction. In this example, the reference axis C extends in the vertical direction. Furthermore, in this example, the hub unit bearing 2, which is the workpiece, is set in the crimping device 38 with its center axis O aligned with the reference axis C, with the axially inner side facing upward and the axially outer side facing downward.

[0078] The stamping die 39 has a processing surface 42 at its tip (the lower end in FIGS. 2 to 3) that has a substantially arc-shaped cross section and is formed in an annular shape around the rotation axis R. The processing surface 42 has a concave profile.

[0079] In this example, the pressing die 39 includes a shaft member 43 and a pressing die main body 44, as shown in FIGS.

[0080] The shaft member 43 has a stepped cylindrical shape.

[0081] The die body 44 is supported and fixed to the tip end (the lower end in FIGS. 3A and 3B) of the shaft member 43. The processing surface portion 42 is provided on the end face of the die body 44 on the tip side.

[0082] The die support mechanism 40 supports the die 39 so that the swing angle θ is adjustable and so that the die 39 can rotate about the rotation axis R. The die support mechanism 40 makes it possible to change the swing angle θ of the die 39 while processing the crimped portion 19, without removing the hub unit bearing 2 from the crimping device 38. In this example, the die support mechanism 40 includes a die support block 45, an aligning bearing 46, and a swing angle changing actuator 47.

[0083] The pressing die support block 45 has a swing angle change axis O, which is the central axis of the pressing die support block 45 and is arranged parallel to the reference axis C. ４５ In this example, the pressing die support block 45 has a cylindrical shape, and is rotatably supported by a plurality of radial bearings 48 inside a block holding recess 59 of a main shaft 57 that constitutes the main shaft drive mechanism 41.

[0084] The pressing die support block 45 is aligned with the reference axis C (swing angle change axis O ４５ The die support recess 49 has a cylindrical inner peripheral surface whose inner diameter does not change in the axial direction of the die support recess 49. ４５ The central axis O of the die support recess 49 relative to the reference axis C ４９ The inclination angle φ (see FIG. 3A) can be set to 0° or more and 30° or less. In this example, the inclination angle φ is set to about 15°. The above values ​​are merely examples and are not limiting.

[0085] The die support recess 49 is also provided with a bearing center O of the aligning bearing 46 disposed inside the die support recess 49. ４６ is the swing angle change axis O ４５ The axial direction of the ...

[0086] The die support recess 49 opens onto at least one of the axially opposite side surfaces of the die support block 45, the side surface closer to the hub unit bearing 2, which is the workpiece, set in the crimping device 38. In this example, the die support recess 49 is configured as a bottomed hole that opens only onto the lower side surface of the die support block 45. In another example, the die support recess can also be configured as a through hole that opens onto both axially opposite side surfaces of the die support block.

[0087] The aligning bearing 46 is disposed between the die 39 and the die support recess 49. This supports the die 39 so that it can rotate about the rotation axis R relative to the die support block 45. In the die support mechanism 40, the die 39 can rotate about the rotation axis (central axis) R. In this example, the aligning bearing 46 is disposed between the base end of the die 39 (the upper end in FIGS. 3A and 3B ) and the die support recess 49.

[0088] The aligning bearing 46 is not particularly limited as long as it can tolerate a certain degree of inclination of the center axis of the inner ring relative to the center axis of the outer ring, and can be constituted by a self-aligning ball bearing, a self-aligning roller bearing, a spherical plain bearing, etc. In this example, the aligning bearing 46 is constituted by a spherical plain bearing.

[0089] The swing angle change actuator 47 moves the pressing die support block 45 along the swing angle change axis O. ４５ Specifically, the swing angle changing actuator 47 uses an actuator 82 such as an electric motor or a hydraulic cylinder as a drive source (second drive source) to rotate the pressing die support block 45 around the swing angle changing axis O. ４５ As a result, in a cross section relative to an imaginary plane including the reference axis C and the rotation axis R, the bearing center O of the aligning bearing 46 (the center of curvature of the outer ring raceway of the aligning bearing 46) that supports the pressing die 39 so that it can rotate about the rotation axis R is４６ and the reference axis C, the swing angle θ can be adjusted by changing the radial distance between them.

[0090] In this example, the swing angle changing actuator 47 includes a link member 50 and an expansion / contraction mechanism 51 .

[0091] The link member 50 has a first arm portion 52 whose lower end is supported and fixed to the center of the upper surface of the mold support block 45 and extends in the axial direction of the mold support block 45, and a second arm portion 53 which extends from the upper end of the first arm portion 52 in the radial direction of the mold support block 45.

[0092] The telescopic mechanism 51 is configured to be able to extend and retract its entire length. Specifically, the telescopic mechanism 51 can be configured with a feed screw mechanism, which is a ball screw mechanism or a sliding screw mechanism, a hydraulic cylinder, or the like. In this example, the telescopic mechanism 51 is configured with a hydraulic cylinder that extends and retracts its entire length as hydraulic oil is supplied and discharged. More specifically, the telescopic mechanism 51 has a cylinder 54 and a piston 55 fitted in the cylinder 54.

[0093] The cylinder 54 is supported by a frame 56 of the crimping device 38 (see FIGS. 3A and 3B) so as to be swingable about a swing axis α that is arranged parallel to the reference axis C.

[0094] The piston 55 has its tip end supported by the tip end of the second arm portion 53 so as to be rotatable about a pivot axis β that is arranged parallel to the reference axis C.

[0095] In the swing angle changing actuator 47 of this example, when hydraulic oil is supplied to or discharged from the cylinder 54, the cylinder 54 swings about the swing axis α, and the entire length of the extension mechanism 51 is extended or contracted. As the entire length of the extension mechanism 51 is extended or contracted, the second arm portion 53 of the link member 50 is pushed or pulled, and the push die support block 45 moves in a direction parallel to the swing angle changing axis α. ４５ As a result, in a cross section relative to an imaginary plane including the reference axis C and the rotation axis R, the bearing center O of the aligning bearing 46 ４６ and the radial distance between the reference axis C is changed, and the swing angle θ is adjusted to a desired angle.

[0096] The spindle drive mechanism 41 drives the die support mechanism 40 to rotate about the reference axis C. Specifically, the spindle drive mechanism 41 uses the electric motor 81 as a drive source (first drive source) to drive the die support block 45 to rotate about the reference axis C. The spindle drive mechanism (first mechanism) 41 performs relative rotation about the reference axis C between the workpiece 90 and the die 39, whose central axis is inclined with respect to the reference axis C. In this example, the spindle drive mechanism 41 includes a spindle 57 and the electric motor 81.

[0097] The main shaft 57 is supported so as to be rotatable about a reference axis C. In this example, the main shaft 57 has a cylindrical shape and is rotatably supported by a plurality of radial bearings 58 with respect to a frame 56 that does not rotate or move during operation of the crimping device 38.

[0098] The main shaft 57 has a central axis O disposed parallel to the reference axis C. ５９ The block holding recess 59 has a cylindrical inner peripheral surface centered at . The block holding recess 59 opens at least to the side surface on both axial sides of the main shaft 57 that is closer to the hub unit bearing 2, which is the workpiece set in the caulking device 38. Inside the block holding recess 59, the pressing die support block 45 is supported by a plurality of radial bearings 48, which are aligned with the swing angle changing axis O, which is the central axis of the pressing die support block 45. ４５ The support allows rotation around the center.

[0099] In this example, the block holding recess 59 is configured as a through hole that opens onto both axial side surfaces of the spindle 57. In another example, the block holding recess can also be configured as a bottomed hole that opens onto only the side surface of the spindle that is closer to the workpiece set in the crimping device.

[0100] The electric motor 81 rotates the main shaft 57 directly or via a reducer.

[0101] The crimping device 38 further includes a support table (support portion, holder) 60 that supports the hub unit bearing 2, which is the workpiece, so as to allow relative movement in the axial direction of the reference axis C with respect to the pressing die 39.

[0102] The support base 60 supports the hub unit bearing 2 without any radial rattle, with its central axis O aligned with the reference axis C, with the axially inner side facing upward and the axially outer side facing downward. In this example, the support base 60 has a recess 61 that opens to the upper surface. The hub unit bearing 2 is supported by the support base 60 by fitting the pilot portion 14 of the hub 5 into the recess 61 without any radial rattle.

[0103] Furthermore, in this example, the support base 60 is supported relative to the frame 56 so as to be movable in the vertical direction, which is the axial direction of the reference axis C, and is movable in the vertical direction by a hydraulic mechanism. In another example, the support base that supports the hub unit bearing can be supported so as not to be able to move in the axial direction of the reference axis, and the pressing die can be configured to be moved in the axial direction of the reference axis by a hydraulic mechanism.

[0104] The crimping device 38 of this example further includes an outer ring drive mechanism 62 that rotates the outer ring 4 of the hub unit bearing 2 relative to the hub body 17 a and the inner ring 16 .

[0105] The outer wheel drive mechanism 62 uses an electric motor (not shown) as a drive source to rotate the outer wheel 4. The structure of the outer wheel drive mechanism 62 is not particularly limited. For example, the outer wheel drive mechanism 62 can be configured to rotate a jig supported and fixed to the stationary flange 8 using the electric motor via a reducer.

[0106] <Crimping joining method> A specific method for plastically deforming the cylindrical portion 37 to form the crimped portion 19 using the crimping processing device 38 of this example will be described using Figures 5(A) to 5(E) in addition to Figures 2 to 4(B)(b).

[0107] First, in the external fitting process, the outer ring 4 and a plurality of rolling elements 6a, 6b are arranged around the hub body 17a, and then the inner ring 16 is inserted between the axially inner row of rolling elements 6b and the fitting shaft portion 18.

[0108] An arrangement step is also carried out in which the hub body 17a, which is the first member, is arranged so that the central axis O of the hub body 17a is coaxial with the reference axis C. In this example, by fitting the pilot portion 14 of the hub 5 into the recess 61 without any radial play, the hub unit bearing 2 is supported on the support base 60 without any radial play, with its central axis O aligned with the reference axis C, and with the axially inner side facing upward and the axially outer side facing downward.

[0109] The order in which the fitting step and the arrangement step are performed is not particularly limited. For example, the outer ring 4 and the plurality of rolling elements 6a, 6b can be arranged around the hub body 17a, and the inner ring 16 can be fitted onto the fitting shaft portion 18, and then the hub unit bearing 2 can be set onto the support base 60 before the crimped portion 19 is formed. Alternatively, the hub body 17a can be set onto the support base 60, and then the outer ring 4 and the plurality of rolling elements 6a, 6b can be arranged around the hub body 17a, and then the inner ring 16 can be fitted onto the fitting shaft portion 18.

[0110] Next, a first forming step is performed to plastically deform the cylindrical portion 37 radially outward. In the first forming step, the pressing die 39 is rotated such that the rotation axis R is at a predetermined first angle θ １ While the die 39 is tilted, it is pressed against the cylindrical portion 37 of the hub body 17a, and the die 39 is rotated around the reference axis C.

[0111] Specifically, in this example, the pressing die support block 45 is moved along the swing angle change axis O by the swing angle change actuator 47 of the pressing die support mechanism 40. ４５ Based on the rotational driving around the reference axis C, the swing angle θ, which is the tilt angle of the rotation axis R with respect to the reference axis C, is set to a predetermined first angle θ １ (See FIG. 5A).

[0112] first angle θ １ The first angle θ can be set to 1° or more and less than 10°, preferably 3° or more and less than 10°, and more preferably 5° or more and less than 10°. １ The above values ​​are merely examples and are not limiting.

[0113] Next, the support base 60 is raised, bringing a circumferential portion of the processing surface 42 of the press die 39 into contact with a circumferential portion of the cylindrical portion 37 of the hub body 17a. Then, by applying an upward load to the hub unit bearing 2 using the support base 60, the circumferential portion of the processing surface 42 is pressed against a circumferential portion of the cylindrical portion 37. The main shaft drive mechanism 41 also drives the press die support block 45 of the press die support mechanism 40 to rotate about the reference axis C, thereby rotating the press die 39. The press die 39 rotates (spins) about the rotation axis R based on the frictional force acting on the contact portion between the processing surface 42 and the axially inner end (first end) of the cylindrical portion 37. The rotation axis R, which is the central axis of the press die 39, whirls around the reference axis C, following the locus of the central axis due to precession. A load directed axially and radially outward is applied to a portion of the circumference of the cylindrical portion 37, and the portion to which the load is applied changes continuously in the circumferential direction, gradually plastically deforming the cylindrical portion 37.

[0114] The number of rotations (rotation speed) of the pressing die 39 around the reference axis C in the first molding step is, for example, 50 min －１ Over 500 min －１ It can be less than 100 min, preferably －１ Over 500 min －１ It can be less than 200 min, and more preferably －１ Over 500 min －１ The above numerical values ​​are merely examples and are not limiting.

[0115] The processing load in the first molding step (the pressing load of the pressing die 39 against the cylindrical portion 37) can be, for example, 10 kN to 200 kN, preferably 30 kN to 150 kN, and more preferably 50 kN to 150 kN. The above numerical values ​​are merely examples and are not limiting.

[0116] When the cylindrical portion 37 has undergone a certain degree of plastic deformation and the gap between the metal material constituting the hub body 17a and the machined surface portion 42 has become large enough to prevent vibration (vibration) of the hub body 17a regardless of the radial force applied from the stamping die 39 (see Figure 5 (B)), the first molding process is completed and the next second molding process is started.

[0117] The timing to end the first forming step can be determined by any means, for example, based on the relationship, which has been determined in advance by experiment, between the amount of plastic deformation of the cylindrical portion 37, the elapsed time from the start of processing, the current value of the electric motor 81 for rotating the pressing die 39 around the reference axis C, and the like.

[0118] In the second molding step, the pressing die 39 is rotated such that the rotation axis R is at a first angle θ １ A predetermined second angle θ greater than ２ While the die 39 is inclined, it is pressed against the cylindrical portion 37 of the hub body 17 a while being rotated about the reference axis C, thereby further deforming the cylindrical portion 37 and forming the crimped portion 19 .

[0119] In this example, after the first molding step is completed, first, the rotational drive of the press die 39 around the reference axis C by the spindle drive mechanism 41 is stopped. Next, the support table 60 is lowered, and as shown in FIG. 5(C), the processing surface portion 42 of the press die 39 is separated from the cylindrical portion 37 of the hub body 17a. In this state, the swing angle changing actuator 47 of the press die support mechanism 40 moves the press die support block 45 around the swing angle changing axis O. ４５ The swing angle θ is set to a predetermined second angle θ ２ (See FIG. 5(D)). That is, between the first molding step (first relative rotation) and the second molding step (second relative rotation), a step of temporarily separating the press die 39 from the workpiece 90 (hub body 17a) is provided. In the separating step, the pressing state (load) on the workpiece 90 (hub body 17a) is temporarily released. The swing angle changing actuator (second mechanism) 47 changes the inclination angle θ of the central axis of the press die 39 relative to the reference axis C. Specifically, the press die support block 45 is moved relative to the swing angle changing axis O. ４５By rotating the bearing 46 around the reference axis C, the bearing center O of the aligning bearing 46 is aligned with the reference axis C in a cross section relative to an imaginary plane including the reference axis C and the rotation axis R. ４６ By increasing the radial distance between the two, the swing angle θ is increased.

[0120] second angle θ ２ The second angle θ can be set to 10° or more and 30° or less, preferably 10° or more and 20° or less, and more preferably 15° or more and 20° or less. ２ The above values ​​are merely examples and are not limiting.

[0121] The oscillation angle θ is set to the second angle θ ２ After changing the position, the support base 60 is raised again, and a circumferential portion of the processing surface 42 of the pressing die 39 is brought into contact with a circumferential portion of the cylindrical portion 37 of the hub body 17a. At this time, the axial position of the hub unit bearing 2 relative to the pressing die 39 (the vertical position of the support base 60 in this example) is adjusted so that the contact surface pressure between the processing surface 42 and the cylindrical portion 37 does not become excessively large. In the adjustment, the center (point of the first inclination angle) P1 of the first angle (first inclination angle) θ1 in the first molding process and the center (point of the first inclination angle) θ2 in the second molding process are adjusted. ２ The axial positions are set to be different between the center (point of the second inclination angle) P2 of the first inclination angle.

[0122] Specifically, for example, the axial position of the hub unit bearing 2 relative to the pressing die 39 is adjusted so that the distance between the intersection P2 of the reference axis C and the rotation axis R and the end (second end) on the other axial side (axially outer side) of the hub body 17a at the start of the second molding step is greater than the distance between the intersection P1 of the reference axis C and the rotation axis R and the end (second end) on the other axial side of the hub body 17a at the end of the first molding step. ２ The center (point of the second tilt angle) is the first angle (first tilt angle) θ １ The second angle (second inclination angle) θ in the second forming step (FIG. 5B) is located outward in the axial direction near the end (near the first end) of the workpiece 90 (hub body 17a) where the crimped portion is provided, compared to the center (point of the second inclination angle) of the second forming step (FIG. 5B).２ The distance along the axial direction between the center (point of the second inclination angle) P2 and the second end portion is the first angle (first inclination angle) θ １ In other words, with regard to the positional relationship with the hub unit bearing 2, which is an assembly of the first member and the second member, the axial position of the hub unit bearing 2 with respect to the pressing die 39 is adjusted so that the intersection P2 of the reference axis C and the rotation axis R at the start of the second molding step is located to one axial side (upper side in this example) of the intersection P1 of the reference axis C and the rotation axis R at the end of the first molding step.

[0123] At the start of the second molding step, the axial position of the hub unit bearing 2 with respect to the pressing die 39 is determined by experiment or by the first angle θ １ , second angle θ ２ It can be calculated in advance based on the values ​​of the above.

[0124] After the machining surface 42 and the cylindrical portion 37 are brought into contact, a circumferential portion of the machining surface 42 is pressed against a circumferential portion of the cylindrical portion 37, while the spindle drive mechanism 41 rotates the die support block 45 of the die support mechanism 40 about the reference axis C, thereby rotating the die 39. This causes the rotation axis R of the die 39 to whirl around the reference axis C, following the locus of the central axis due to precession. A load directed axially and radially outward is applied to a circumferential portion of the cylindrical portion 37, and the portion to which the load is applied changes continuously in the circumferential direction. The cylindrical portion 37 is further plastically deformed, forming the crimped portion 19 (see FIG. 5(E)).

[0125] The rotation speed of the press die 39 around the reference axis C in the second molding step can be the same as or different from the rotation speed of the press die 39 around the reference axis C in the first molding step. The rotation speed of the press die 39 around the reference axis C in the second molding step can be, for example, 50 min. －１ Over 500 min －１ It can be less than 100 min, preferably －１ Over 500 min －１It can be less than 200 min, and more preferably －１ Over 500 min －１ The above numerical values ​​are merely examples and are not limiting.

[0126] The processing load in the second forming step can be the same as or different from the processing load in the first forming step. The processing load in the second forming step can be, for example, 10 kN or more and 300 kN or less, preferably 50 kN or more and 300 kN or less, and more preferably 100 kN or more and 300 kN or less. The above numerical values ​​are merely examples and are not limiting.

[0127] The timing to end the second forming step can be determined by any means, for example, based on the relationship, which has been determined in advance by experiment, between the amount of plastic deformation of the cylindrical portion 37 and the elapsed time from the start of processing or the current value of the electric motor 81 that rotates the pressing die 39 about the reference axis C.

[0128] In the first forming step (first relative rotation), the load point (load area) where the load is applied from the die 39 to the hub body (first member) 17a changes circumferentially on the cylindrical portion 37 (crimped portion 19) of the hub body 17a (orbital forging). In the first forming step, orbital forging applies a load to the hub body 17a, including a load component directed radially outward, particularly using the radially inner region of the processing surface portion 42 of the die 39, and the position at which the load is applied moves circumferentially. A portion of the hub body 17a deforms radially outward.

[0129] In the second forming step (second relative rotation), the load-bearing point (load-bearing area) where the load is applied from the die 39 to the hub body (first member) 17a also changes circumferentially on the hub body 17a (orbital forging). In the second forming step, orbital forging uses the radially outer region of the processing surface 42 of the die 39 in particular, and a load including a load component directed radially inward is applied to the radially outer portion of the hub body 17a, and the position at which the load is applied moves circumferentially. A portion of the hub body 17a is deformed radially inward.

[0130] At least one of the movement, position, and posture of the press die 39 differs between the first molding process and the second molding process. The axial position and / or load direction differs between the first loaded point (first loaded area) in the first relative rotation and the second loaded point (second loaded area) in the second relative rotation. The shortest axial distance between the loaded point and the second end in the second molding process (second relative rotation) is shorter than the shortest axial distance between the loaded point and the second end in the first molding process (first relative rotation). In the second molding process, a force that compresses the crimped portion 19 in the axial direction and is directed inward relative to the radial direction (a load that includes a component directed radially inward) is applied to the crimped portion 19 from the radially outer side of the processing surface portion 42 of the press die 39. A portion of the crimped portion 19 flows radially inward. Radial expansion of the inner ring 16 due to the formation of the crimped portion 19 is prevented or suppressed. Cracks in the inner ring 16 due to the formation of the crimped portion 19 are prevented, preload variations are suppressed, and / or rotational resistance (friction) against the outer ring is suppressed.

[0131] In this example, while processing to plastically deform the cylindrical portion 37 is being performed in the first and second forming steps, specifically while a processing load is being applied to the cylindrical portion 37 (caulking portion 19), the outer ring 4 is rotationally driven by the outer ring drive mechanism 62. This causes the rolling elements 6a, 6b to rotate and revolve, preventing indentations from being formed in the outer ring raceways 7a, 7b and the inner ring raceways 10a, 10b as the cylindrical portion 37 is plastically deformed.

[0132] In the manufacturing method of the hub unit bearing 2 of this example, the cylindrical portion 37 is plastically deformed to form the crimped portion 19, thereby joining the hub body 17 and the inner ring 16, and then the hub-side face spline 12 is formed on the axially inner end face of the crimped portion 19.

[0133] The method for forming the hub-side face spline 12 is not particularly limited. For example, the hub-side face spline 12 can be formed by a general forging press process in which a processed portion formed by alternately arranging recesses and protrusions in the circumferential direction is pressed. Alternatively, the hub-side face spline 12 can be formed by orbital forging in which a forming die supported so as to be rotatable about a central axis inclined with respect to the central axis O of the hub unit bearing 2 is pressed against the crimped portion 19 while rotating about the central axis O of the hub unit bearing 2.

[0134] In this example, in the first forming step, which is the initial stage of the process for forming the crimped portion 19, the swing angle θ of the pressing die 39 is set to a relatively small first angle θ １ In this state, the cylindrical portion 37 is subjected to a rocking and crimping process using the die 39, thereby causing plastic deformation. As a result, in the initial stages of processing to form the crimped portion 19, the hub body 17a (hub unit bearing 2) is prevented from vibrating (moving wildly), and a decrease in processing accuracy is prevented.

[0135] In the first forming step, the cylindrical portion 37 is plastically deformed to a certain extent, and then in the second forming step, the swing angle θ of the pressing die 39 is set to a relatively large second angle θ ２ In this state, the cylindrical portion 37 is subjected to a rocking and crimping process using the die 39, thereby further plastically deforming it and forming the crimped portion 19. This prevents the load applied from the die 39 to the cylindrical portion 37 (crimped portion 19) from becoming unnecessarily large from the middle stage to the end stage of the process of forming the crimped portion 19. This makes it possible to suppress radial outward expansion of the inner ring 16, thereby preventing the generation of hoop stress within the inner ring 16 or minimizing the hoop stress generated within the inner ring 16.

[0136] In particular, in this example, the swing angle θ is set to a relatively small first angle θ １ a first forming step in which the rocking and pressing process is performed in a state in which the rocking angle θ is set to a relatively large second angle θ ２The first forming process and the second forming process, in which rocking and crimping are performed in a state in which the hub unit bearing 2 is in a rocking state, are performed using the same press die 39. Specifically, after the first forming process is performed by the crimping device 38, the rocking angle θ of the press die 39 of the crimping device 38 is changed and the second forming process is performed. In short, the first forming process and the second forming process, which have different rocking angles θ, are performed by a single crimping device 38. This prevents the manufacturing line for the hub unit bearing 2 from becoming unnecessarily long, making it easier to reduce costs.

[0137] FIG. 6 is a partial schematic diagram of a vehicle 200 equipped with a hub unit bearing (bearing, bearing device) 151. The above-described bearing can be applied to both hub unit bearings for driving wheels and hub unit bearings for driven wheels. In FIG. 6, the hub unit bearing 151 is for a driving wheel and includes an outer ring 152, a hub 153, and multiple rolling elements 156. The outer ring 152 is fixed to a knuckle 201 of a suspension device using bolts or the like. The wheel 202 (and the braking rotor 22) is fixed to a flange (rotating flange) 153A provided on the hub 153 using bolts or the like. The vehicle 200 can also have a support structure similar to that described above for the hub unit bearing 151 for the driven wheel.

[0138] The technical scope of the present invention is not limited to the scope of the embodiments. Various modifications or improvements can be made to the embodiments. Forms incorporating such modifications or improvements can also be included in the technical scope of the present invention. Furthermore, the present invention is not limited to the described embodiments, and any combination of these configurations may be used.

[0139] The present disclosure includes the following configurations and / or combinations.

[0140] In one aspect, a crimping method includes the steps of setting a workpiece, in which a first member and a second member are axially assembled, along a reference axis and forming a crimped portion in the first member. The step of forming the crimped portion includes deforming the first member using a first relative rotation about the reference axis between a first pressing die and the workpiece, and further deforming the first member using a second relative rotation about the reference axis between a second pressing die and the workpiece. During the first relative rotation, a central axis of the first pressing die is tilted with respect to the reference axis at a first tilt angle. During the second relative rotation, a central axis of the second pressing die is tilted with respect to the reference axis at a second tilt angle different from the first tilt angle.

[0141] In the crimping method according to the above aspect, the positions in the axial direction are different between the center of the first inclination angle and the center of the second inclination angle.

[0142] In the crimping joining method according to the above aspect, the center of the second inclination angle is located outward in the axial direction compared to the center of the first inclination angle near the end of the first member where the crimped portion is provided.

[0143] In the crimping joining method according to the above aspect, the first pressing die and the second pressing die may be the same pressing die, or may be different pressing dies.

[0144] In the crimping joining method of the above aspect, the first press die and the second press die are the same press die, and the method further includes a step of temporarily separating the first press die from the workpiece between the first relative rotation and the second relative rotation.

[0145] In another aspect, a method for manufacturing a hub unit bearing uses the above-described crimping method to manufacture a hub unit bearing.

[0146] In another aspect, a method for manufacturing a vehicle includes manufacturing a hub unit bearing using the manufacturing method described above, and assembling a vehicle using the hub unit bearing.

[0147] In another aspect, a method of manufacturing a mechanical device comprises manufacturing a crimped assembly using the crimping method described above, and assembling a mechanical device using the crimped assembly.

[0148] In another aspect, a crimping apparatus includes a reference axis, a holder for supporting a workpiece, a stamping die having a central axis, a first mechanism for performing relative rotation between the workpiece and the stamping die, the central axis of which is inclined relative to the reference axis, about the reference axis, and a second mechanism for changing the tilt angle of the central axis relative to the reference axis. During the first relative rotation, the central axis of the stamping die is inclined relative to the reference axis by a first tilt angle. During the second relative rotation, the central axis of the stamping die is inclined relative to the reference axis by a second tilt angle different from the first tilt angle.

[0149] In the caulking device according to the above aspect, the axial positions of the center of the first tilt angle and the center of the second tilt angle are different from each other.

[0150] In the crimping apparatus according to the above aspect, the first mechanism has a first drive source, and the second mechanism has a second drive source different from the first drive source.

[0151] In the crimping processing device of the above aspect, the mold has a first mold used for the first relative rotation and a second mold used for the second relative rotation, and the first mold and the second mold are the same mold or are different molds from each other.

[0152] In another aspect, a crimping method includes an outer fitting step of fitting a cylindrical second member onto a first member having a cylindrical portion at one axial end thereof, a first forming step, and a second forming step. In the first forming step, a first pressing die, supported for rotation about a first rotation axis that is its central axis, is pressed against the one axial end of the cylindrical portion while rotating the first member about the central axis, with the first rotation axis tilted at a predetermined first angle with respect to the central axis of the first member, thereby plastically deforming the cylindrical portion. In the second forming step, after the first forming step, a second pressing die, supported for rotation about a second rotation axis that is its central axis, is pressed against the one axial end of the cylindrical portion while rotating the first member about the central axis, with the second rotation axis tilted at a predetermined second angle that is larger than the first angle with respect to the central axis of the first member, thereby further plastically deforming the cylindrical portion and forming a crimped portion that presses against the one axial end face of the second member.

[0153] In the crimping method of the above aspect, the first pressing die and the second pressing die can be the same, that is, the first molding step and the second molding step can be performed using the same device.

[0154] In the crimping joining method of the above aspect, the distance between the intersection of the center axis of the first member and the second rotation axis and the end portion of the first member on the other axial side at the start of the second molding process can be made larger than the distance between the intersection of the center axis of the first member and the first rotation axis and the end portion of the first member on the other axial side at the end of the first molding process.

[0155] The crimping connection method in the above aspect may further include, after the second molding step, a spline forming step of forming a face spline on one axial end face of the crimped portion by arranging recesses and protrusions alternately in the circumferential direction.

[0156] In the crimping joining method according to the above aspect, the first angle may be set to be equal to or greater than 3° and less than 10°, and the second angle may be set to be equal to or greater than 10° and less than 30°.

[0157] In another aspect, a hub unit bearing that is the subject of the manufacturing method for a hub unit bearing comprises an outer ring having a plurality of outer ring raceways on its inner peripheral surface, a hub having a plurality of inner ring raceways on its outer peripheral surface, and rolling elements arranged between the plurality of outer ring raceways and the plurality of inner ring raceways, with multiple rolling elements arranged in each row.

[0158] The hub comprises an inner ring having at least the axially innermost inner ring raceway of the plurality of inner ring raceways on its outer surface, a fitting shaft portion onto which the inner ring is fitted, and a hub body having a crimping portion provided at the axially inner end portion and pressing against the axially inner end face of the inner ring.

[0159] In one aspect, in a method for manufacturing a hub unit bearing, the hub body and the inner ring are joined by the crimping method of one aspect of the present disclosure, in which the first member is constituted by the hub body and the second member is constituted by the inner ring.

[0160] In the manufacturing method of the hub unit bearing in the above aspect, the outer ring can be driven to rotate relative to the hub body and the inner ring throughout the process of forming the crimped portion.

[0161] In another aspect, a vehicle that is the subject of a vehicle manufacturing method includes a hub unit bearing.

[0162] In one aspect, in a method for manufacturing a vehicle, the hub unit bearing is manufactured by the method for manufacturing a hub unit bearing according to one aspect of the present disclosure.

[0163] In another aspect, a mechanical device that is the subject of a mechanical device manufacturing method comprises a first member and a second member fitted onto the first member, and a crimping portion provided at one end of the first member prevents the second member from displacing axially to one side relative to the first member.

[0164] In one aspect, in a method for manufacturing a mechanical device, the first member and the second member are joined by a crimping joining method according to one aspect of the present disclosure.

[0165] In another aspect, the crimping processing device includes a die, a die support mechanism that supports the die so that the inclination angle of the rotation axis, which is the central axis of the die, relative to a reference axis can be adjusted and so that the die can rotate around the rotation axis, and a spindle drive mechanism that drives the die support mechanism to rotate around the reference axis.

[0166] The caulking apparatus in the above aspect may further include a support table that supports the workpiece so as to be movable relative to the pressing die in the axial direction of the reference axis.

[0167] In the crimping processing device of the above aspect, the die support mechanism can include a die support block having a die support recess formed in a direction inclined relative to the reference axis and supported so as to be rotatable around a swing angle change axis arranged parallel to the reference axis, an aligning bearing arranged between the die and the die support recess, and a swing angle change actuator that rotates the die support block around the swing angle change axis.

[0168] In the crimping processing device of the above aspect, the spindle drive mechanism can include a spindle that is formed in the axial direction of the reference axis at a portion radially offset from the reference axis, has a block holding recess inside which the die support block is supported, and is supported so as to be rotatable around the reference axis, and an electric motor that rotatably drives the spindle.

[0169] REFERENCE SIGNS LIST 1 Wheel drive unit 2 Hub unit bearing 3 Constant velocity joint 4 Outer ring 5 Hub 6a, 6b Rolling elements 7a, 7b Outer ring raceway 8 Stationary flange 9 Flange side support hole 10a, 10b Inner ring raceway 11 Center hole 12 Hub side face spline 13 Rotating flange 14 Pilot portion 15 Mounting hole 16 Inner ring 17, 17a Hub body 18 Fitting shaft portion 19 Caulking portion 20 Step surface 21a, 21b Cage 22 Joint outer ring 23 Joint inner ring 24 Ball 25 Joint side face spline 26 Mouth portion 27 Cylindrical portion 28 Circumferential wall portion 29 Side wall portion 30 Outer diameter side engagement groove 31 Female thread portion 32 Inner diameter side engagement groove 33 Spline hole 34 Bolt 35 Shaft portion 36 Head portion 37 Cylindrical portion 38 Caulking device 39 Die 40 Die support mechanism 41 Spindle drive mechanism 42 Processing surface portion 43 Shaft member 44 Die body 45 Die support block 46 Aligning bearing 47 Oscillation angle change actuator 48 Radial bearing 49 Die support recess 50 Link member 51 Extension mechanism 52 First arm portion 53 Second arm portion 54 Cylinder 55 Piston 56 Frame 57 Spindle 58 Radial bearing 59 Block holding recess 60 Support base 61 Recess 62 Outer wheel drive mechanism

Claims

1. a step of setting a workpiece in which a first member and a second member are axially assembled along a reference axis; forming a crimped portion in the first member, the step including: deforming the first member using a first relative rotation about the reference axis between a first pressing die and the workpiece; and further deforming the first member using a second relative rotation about the reference axis between a second pressing die and the workpiece; Equipped with In the first relative rotation, a central axis of the first pressing die is inclined with respect to the reference axis at a first inclination angle; In the second relative rotation, the central axis of the second pressing die is inclined with respect to the reference axis at a second inclination angle different from the first inclination angle, a center of the second inclination angle is located outward in the axial direction compared to a center of the first inclination angle in a vicinity of an end portion of the first member where the crimping portion is provided, the first tilt angle is equal to or greater than 3° and less than 10°, and the second tilt angle is equal to or greater than 10° and less than 30°; Crimping joining method.

2. The first mold and the second mold are the same mold or are different molds. The crimping method according to claim 1.

3. the first pressing die and the second pressing die are the same pressing die, further comprising the step of temporarily separating the first pressing die from the workpiece between the first relative rotation and the second relative rotation. The crimping method according to claim 1.

4. A method for manufacturing a hub unit bearing, comprising manufacturing a hub unit bearing using the crimping method according to any one of claims 1 to 3.

5. Manufacturing a hub unit bearing using the manufacturing method according to claim 4; Assembling a vehicle using the hub unit bearing; A method for manufacturing a vehicle, comprising:

6. Manufacturing a crimped assembly using the crimping method according to any one of claims 1 to 3; assembling a mechanical device using the swage assembly; A method for manufacturing a mechanical device, comprising:

7. A reference axis; a holder for supporting a workpiece; a pressing die having a central axis and rotatably supported on a block via a bearing; a first mechanism that rotates the workpiece relative to the pressing die, the central axis of which is inclined with respect to the reference axis, around the reference axis; a second mechanism that changes the tilt angle of the central axis with respect to the reference axis, In the first relative rotation, the central axis of the stamping die is inclined with respect to the reference axis at a first inclination angle, and in the second relative rotation, the central axis of the stamping die is inclined with respect to the reference axis at a second inclination angle different from the first inclination angle, the first mechanism has a rotating body supported rotatably about the reference axis, the block is supported by the rotor so as to be rotatable about a block axis that is parallel to the reference axis; the second mechanism changes the distance between the reference shaft and the bearing between the first relative rotation and the second relative rotation. Crimping processing equipment.

8. The positions in the axial direction between the center of the first tilt angle and the center of the second tilt angle are different from each other. The crimping device according to claim 7.

9. the first mechanism has a first drive source; the second mechanism has a second drive source different from the first drive source; The crimping device according to claim 7 or 8.

10. The pressing mold includes a first pressing mold used for the first relative rotation and a second pressing mold used for the second relative rotation, The first mold and the second mold are the same mold or are different molds. The crimping device according to claim 7 or 8.