JP5283317B2 - Manufacturing method of wheel bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the bearing unit for wheel which can make the caulking process to enlarge the diameter up to the necessary processing degree and its manufacturing method which can prevent the coming off an inner ring in the assembling process to a vehicle without giving the bad influence to the bearing function while preventing a caulking punch and the interference of a hub wheel. <P>SOLUTION: This bearing unit for wheel supports the driving wheel as a rolling body of a double row is interposed between the raceway faces which an outward member and an inward member are opposed. The inward member is consisting of the hub wheel 9 and the inner ring 10 which is fitted to the outer circumference of the hub wheel 9 and the in-board side end. A step part 16 of an equivalent depth to the inner rim of an end face is provided with the inner circumference face of the inner ring 10. The inner face of the end part of the step part 16 is formed of a straight part 16b consisting of a cylindrical face and a subsequent slope face 16a to the inner circumference face of the inner ring 10 from the end of this straight part 16b. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

The present invention relates to a method of manufacturing a wheel bearing device such as an automobile smell Te rotatably supporting the vehicle wheel.

  Conventionally, what is shown in FIG. 9 is proposed as a wheel bearing device for driving wheel support (for example, patent document 1). This is because ball-shaped rolling elements 25 are interposed in double rows between the raceway surfaces 23 and 24 where the outer member 21 and the inner member 22 face each other, and the inner member 22 is surrounded by the wheel mounting hub flange 29a. And the inner ring 30 fitted to the outer periphery of the inboard side end of the hub ring 29. The stem portion 33a of the outer ring 33 of the constant velocity joint is inserted into the central hole 31 of the hub wheel 29 and is spline-fitted, and the step surface 33b of the constant velocity joint outer ring 33 is pressed against the inboard side end surface 30a of the inner ring 30. It is done. In this state, the inner member 22 is tightened by the constant velocity joint outer ring 33 and the nut 34 by screwing the nut 34 into the tip of the stem portion 33a.

  As shown in FIG. 10 showing a part of FIG. 9 in an enlarged manner, in this proposed example, the inner ring 30 is fitted on the stepped portion 35 formed on the outer periphery of the inboard side end portion of the hub wheel 29, and the inner ring 30 is A stepped portion 36 is formed on the inner periphery of the inboard side end portion, the inboard side end of the hub wheel 29 is swung and squeezed to expand the outer diameter side, and the plastically deformed portion 29b is replaced with the inner ring 30. The step 36 is crimped. As a result, the inner ring 30 is prevented from coming off due to an external force generated during assembly to the vehicle.

JP-A-9-164803

The wheel bearing device described in Patent Document 1 has the following problems.
(1) Since the plastic deformation portion 29b of the hub ring 29 is large, it is necessary to increase the radial step of the step portion 36 formed at the inboard side end portion of the inner ring 30 (for example, a radius difference of about 5 to 7 mm). When the level difference of the stepped portion 36 is increased, the area of the inboard side end surface 30a of the inner ring 30 is reduced, so that the contact surface pressure with the cross section 33b of the constant velocity joint outer ring 33 is increased. Therefore, it causes wear and abnormal noise.
(2) When the plastic deformation portion 29b of the hub ring 29 is to be stored inside (outboard side) from the inboard side end of the inner ring 30, the axial length of the step portion 36 of the inner ring 30 is increased (for example, 7 to 8 mm). Degree). As described above, when the axial length of the inner ring step portion 36 is increased, the inner ring step portion 36 tends to be positioned on the extension line of the rolling element contact angle, and deformation of the inner ring due to a load load during operation increases, resulting in a short life. There is a possibility. Further, when the axial length of the inner ring step portion 36 is increased, the fitting length (area) of the inner ring 30 to the hub ring 29 is reduced accordingly, so that inner ring creep occurs and the bearing life may be reduced. . These problems can be avoided by increasing the width of the entire inner ring, but this requires extra space in the width direction.
(3) Further, since the plastic deformation portion 29b of the hub wheel 29 is large, in the swing caulking process, the caulking punch interferes with the inner ring 30, and the machining is difficult.

  In order to solve such a problem, as shown in FIG. 11, an attempt was made to make the stepped portion 36 of the inner ring 30 shallow with a depth corresponding to the inner peripheral edge of the inner ring end face 30a. Even if the stepped portion 36 is made shallow, sufficient resistance against pulling force acting when the bearing is assembled to the vehicle can be obtained.

  In the case of such a plastically deformed portion 29b with respect to the small step portion 36, when performing the caulking process, the caulking process can be performed without using the swing caulking. For example, as shown in FIG. 12, the bearing device is fixed with the inboard side facing upward, and in this state, the caulking punch 37 is lowered onto the inboard side end of the hub wheel 29, and the hub wheel 29 A method of pressing the plastically deformed portion 29b over the entire circumference can be used. The amount of caulking of the plastic deformation portion 29b is controlled as follows. That is, in order to obtain the targeted diameter expansion deformation and protrusion height of the inboard side end of the hub wheel 29, the shaft diameter of the hub wheel 29, the thickness of the inboard side end of the hub wheel 29, and the axial length. The working load of the crimping punch 37 is determined in consideration of factors such as the shape of the inner ring step portion 36.

  However, when pressing with a predetermined processing load, caulking punches that affect the processing accuracy, such as the hardness of the base metal, the heat treatment range, the dimensions of the plastic deformation part, etc., and the punch insertion load. In other words, there is a problem that it is difficult to obtain a stable crimped shape because it is impossible to cope with the above conditions (surface deterioration, attached oil condition, etc.).

  Further, it is desirable that the caulking equipment is low-cost and compact, and therefore the processing load needs to be as small as possible. In order to reduce the processing load, it is preferable that the taper angle α of the taper surface 37a of the crimping punch 37 is small as shown in FIG. However, when the diameter is expanded to the same diameter (ΦC in the figure), the axial dimension D required for the hub crimped surface 29c shown in FIG. If this axial dimension D becomes longer, the tip corner portion 37b of the caulking punch 37 and the root 29d of the hub caulking portion may interfere with each other as shown in FIG.

  On the other hand, the hub inner diameter surface 29e shown in FIG. 14A may become a guide surface of the stem portion of the constant velocity joint, and in order to secure this guide length, the caulking processing allowance (F dimension) must be increased. I can't. Further, if the R portion (symbol R1) of the root 29d of the hub caulking portion is reduced, the rigidity of the hub is reduced. Further, as shown in FIG. 14B, when the tip length of the punch 37 is shortened and the tip diameter ΦG is increased, the tip of the punch 37 comes into contact with the hub end surface 29f and the chamfered portion 29g at the time of crimping. There is a possibility that processing cannot be performed or burrs are generated.

The object of the present invention is to prevent the inner ring from slipping off during the assembly process to the vehicle without adversely affecting the bearing function, and to prevent the interference between the caulking punch and the hub wheel, while expanding the diameter to the required degree of processing. it is to provide a method of manufacturing a wheel bearing equipment machining can be performed.

The wheel bearing device manufactured by the method of the present invention is interposed between an outer member having a double-row raceway surface on the inner periphery, an inner member having a raceway surface facing these raceway surfaces, and the opposite raceway surface. The inner member is fitted to a hub wheel having a hub flange for wheel mounting on the outer periphery and a through hole in the center, and an outer periphery of the inboard side end of the hub wheel. An inner ring is used for driving wheel support in which the raceway surface of each row is formed on the hub ring and the inner ring.
In this wheel bearing device, a stepped portion that extends to the end surface on the inboard side of the inner ring is provided on the inner peripheral surface of the inner ring, and an inner surface of the stepped portion is formed with a straight portion formed of a cylindrical surface and an end of the straight portion. from part a shape formed of an inclined surface following the inner peripheral surface of the inner ring, the plastic deformation portions set only for engaging the inclined surface of the step portion of the inner ring by caulking of the wheel hub, the said inner ring the depth of the stepped portion, said smaller depth Satoshi enough to prevent the inner ring of the omission in the assembly process of the vehicle by the engagement of the plastic deformation portion of the hub wheel, before Symbol plastically deformed portion does not protrude from the end face of the inner ring It shall be the thing. A stem portion of the outer ring of the constant velocity joint is inserted into the through hole of the hub wheel, and the hub wheel is coupled to the outer ring of the constant velocity joint by tightening a nut that is screwed to the tip of the stem portion. The end surface facing the side is pressed against the step surface facing the outboard side provided on the outer ring of the constant velocity joint .

In this wheel bearing device, the inboard side end portion of the hub wheel is enlarged by plastic deformation by caulking, and the plastic deformation portion is engaged with the inclined surface of the inner ring stepped portion, thereby restricting the inner ring from coming off. It is a configuration. In this configuration, the inner ring stepped portion has a depth small enough to prevent the inner ring from coming off in the assembly process to the vehicle by engaging the plastically deformed portion of the hub wheel . The step can be made as small as possible. For this reason, the decrease in the area of the inner ring end face can be reduced while providing the stepped portion, the increase of the contact surface pressure with the stepped face of the constant velocity joint outer ring is suppressed, and the occurrence of wear and noise can be prevented. Even if the step portion on the inner peripheral surface of the inner ring is made small as described above, a sufficient proof strength can be obtained with respect to the pull-out force acting when the bearing is assembled to the vehicle. In this way, by setting the inner ring stepped portion as small as possible within the range in which the inner ring can be secured, it is possible to prevent the inner ring from being removed during the assembly process to the vehicle without adversely affecting the bearing function.

Further, when the plastic deformation portion of the hub ring is caulked, the plastic deformation portion of the hub ring can be easily plastically deformed along the inclined surface of the inner ring step portion. For this reason, proper caulking can be performed, and the securing of the pull-out strength is further ensured.
Further, the end of the inboard side of the hub wheel is crimped with a caulking punch having a tapered outer peripheral surface and chamfered corners between the tapered surface and the tip surface on the inboard side of the hub wheel. Since it is performed by pushing it into the inner periphery of the end, it is possible to accurately and easily perform diameter expansion caulking to the required degree of processing without interference of the caulking punch with the hub wheel during caulking pressure. it can.

The through hole of the front Symbol hub wheel, a constant velocity universal has a spline groove to mesh with the outer periphery of the spline of the stem portion of the joint on the inner peripheral surface, one said spline grooves at the inner circumferential surface of the through hole is formed般径A portion on the inboard side of the portion, a large-diameter step portion that becomes an inner peripheral surface of the plastic deformation portion, and an intermediate-diameter step portion that is smaller in diameter than the large-diameter step portion and larger in diameter than the general-diameter portion. It is good to have a two-step step shape.
When this configuration is adopted, the inboard side end of the hub wheel where the large-diameter step portion of the through hole becomes the inner peripheral surface is crimped as a plastically deformed portion, thereby preventing the inner ring from coming off in the assembly process to the vehicle, and The spline on the outer periphery of the stem portion of the constant velocity universal joint is engaged with the spline groove formed in the general diameter portion of the through hole, and the stem portion of the constant velocity universal joint is spline fitted into the through hole.
The plastically deformed portion is a portion having a large inner diameter and a small thickness in the hub wheel, and since the entire volume is small, the inner ring stepped portion can be made small and the caulking process is facilitated. . In addition, the through hole has a two-stepped shape with a larger inner diameter on the inboard side. Therefore, when the stem part of the constant velocity universal joint is spline-fitted to the general diameter part of the through hole, the constant velocity is freely adjustable. The stem portion of the joint is easy to insert from the inboard side, and assembly work is easy.

Raceway surface before Symbol hub wheel is a surface hardening treatment surface that is quenching, the caulking portion is a non-heat treated portion, the inner ring may whole from the surface to the core portion is cured by quenching.
It is preferable that the raceway surface of the hub ring has a high hardness as a surface-hardened surface from the viewpoint of improving the rolling life. It is preferable to do. Since the inner ring is a small part and has a raceway surface, and the inner diameter surface is fitted to the hub ring, it is assumed that the entire surface from the surface to the core is hardened by a quenching process. This is preferable in terms of improving the wear resistance of the fitting surface.

The method for manufacturing a wheel bearing device according to the present invention is applied to the wheel bearing device having the above-described configuration , and the plastically deformed portion has a cylindrical shape before deformation , and the diameter of the tip surface is the above-described diameter. than the through holes distal outer circumferential surface a large diameter becomes tapered surface and the crimping punch chamfered corners has been applied between the tapered surface and the distal end surface on the inner periphery of the inboard end of the hub caulking Me in the radially enlarged state over the entire circumference by pushing in the axial direction, said by controlling the stroke of the axial pushing the caulking punch, and also adjust the outer diameter and the inner diameter of the plastic deformation portion after crimping It is characterized by.
The axial stroke for pressing the caulking punch may be controlled by using the end face of the hub wheel as a stroke reference for the caulking punch.
For controlling the axial stroke for pushing the caulking punch, the end face of the inner ring may be used as the stroke reference of the caulking punch.
The axial stroke for pressing the caulking punch may be controlled by using the position where the caulking punch is in contact with the hub wheel as a stroke reference for the caulking punch.

  According to this manufacturing method, a caulking punch having a chamfered corner between the tapered surface and the tip surface is axially pushed into the inner periphery of the end of the inboard side of the hub wheel so that the diameter is expanded. Thus, interference between the caulking punch and the hub wheel can be prevented, and the diameter-enlarging caulking process up to a required degree of machining can be performed accurately and easily. In addition, it is possible to always stably press the plastically deformed portion so that the radial expansion and the protrusion height are constant, so that it is possible to reliably prevent the finished product from coming off the inner ring.

The method for manufacturing a wheel bearing device according to the present invention includes an outer member having a double-row raceway surface on an inner surface, an inner member having a raceway surface facing the raceway surface, and a composite member interposed between the opposing raceway surfaces. An inner ring fitted with an outer periphery of an inboard side end of the hub wheel, the inner member including a rolling element in a row, and the inner member has a hub flange for wheel mounting on the outer periphery and a through hole in the center. The hub race and the inner race form the raceway surface of each row, and the inner circumference of the inner race is provided with a stepped portion that extends to the end surface on the inboard side of the inner race. A straight portion made of a cylindrical surface and an inclined surface that continues from the end of the straight portion to the inner peripheral surface of the inner ring, and is engaged with the inclined surface of the step portion of the inner ring by caulking of the hub ring. only set plastic deformation portion case, the depth of the stepped portion of the inner ring, Serial depth smaller Satoshi to the extent that can be prevented inner ring of the omission in the assembly process of the vehicle by the engagement of the plastic deformation portion of the hub wheel, before Symbol plastically deformed portion shall not protrude from the end face of the inner ring, the hub wheel A stem portion of the outer ring of the constant velocity joint is inserted into the through hole of the inner ring, and the hub ring is coupled to the outer ring of the constant velocity joint by tightening a nut that is screwed to the tip of the stem portion, and faces the inboard side of the inner ring. a method of end faces to produce a wheel bearing apparatus for a driving wheel support is pressed against the stepped surface facing the outboard side which is provided on the outer ring of the constant velocity joint, the plastic deformation portion, the undeformed shape A hub ring is a caulking punch that has a cylindrical shape, the tip surface having a diameter larger than that of the through hole, the tip outer peripheral surface becomes a tapered surface, and the corner between the tapered surface and the tip surface is chamfered. By caulking to the inner circumference of the inboard side end in the axial direction, the outer diameter of the plastically deformed part after caulking is controlled by controlling the axial stroke for pushing the caulking punch into the expanded state over the entire circumference. Because the inner diameter is adjusted, there is no interference between the caulking punch and the hub wheel during caulking, and the diameter-enlarging caulking process to the required degree of machining can be performed accurately and easily, with less variation in machining accuracy. The wheel bearing device can always be manufactured with high accuracy and stability.

An embodiment of the present invention will be described with reference to FIGS. This embodiment is a third generation type inner ring rotation type and is applied to a wheel bearing device for driving wheel support. In this specification, the side closer to the outer side in the vehicle width direction of the vehicle when attached to the vehicle is referred to as the outboard side, and the side closer to the center of the vehicle is referred to as the inboard side.
The wheel bearing device includes an outer member 1 having a double-row raceway surface 3 formed on the inner periphery, an inner member 2 having a raceway surface 4 opposed to each raceway surface 3, and these outer members 1. And rolling elements 5 composed of double-row balls interposed between the raceway surfaces 3 and 4 of the inner member 2. This wheel bearing device is a double-row outward angular ball bearing type, and the rolling elements 5 are held by a cage 6 for each row. The raceway surfaces 3 and 4 have an arcuate cross section, and the raceway surfaces 3 and 4 are formed such that the rolling element contact angle θ is back to back. Both ends of the bearing space between the outer member 1 and the inner member 2 are sealed by seals 7 and 8, respectively.

The outer member 1 is a member on the fixed side, and has a flange 1a attached to the knuckle in the suspension device (not shown) of the vehicle body on the outer periphery, and the whole is an integral part.
The inner member 2 is a member on the rotation side, and has a hub wheel 9 having a hub flange 9a for wheel attachment on the outer periphery, and an inner ring 10 fitted to the outer periphery of the inboard side end of the hub wheel 9; It becomes. The hub ring 9 and the inner ring 10 are formed with the raceway surfaces 4 of the respective rows. The hub wheel 9 has a through hole 11 in the center, and the raceway surface 4 is a surface-hardened surface by quenching. The entire inner ring 10 from the surface to the core is hardened by a quenching process.

  As shown in the enlarged cross section of FIG. 2, the through hole 11 of the hub wheel 9 has a general diameter portion 11a that occupies from the outboard side end to the vicinity of the inboard side end, and on the inboard side from the general diameter portion 11a. And an intermediate-diameter step portion 11b having a larger diameter than the general-diameter portion 11a, and a large-diameter step portion 11c that is further inboard than the intermediate-diameter step portion 11b and larger in diameter than the intermediate-diameter step portion 11b. It is set as the two-step step shape which becomes. A spline groove 11d that meshes with the spline on the outer periphery of the stem portion 13a of the constant velocity universal joint 12 is formed on the inner peripheral surface of the general diameter portion 11a.

A stepped inner ring fitting surface portion 15 having a smaller diameter than the outer periphery of the other portion of the hub wheel 9 is formed on the outer periphery of the inboard side end of the hub wheel 9, and the inner ring 10 is formed on the inner ring fitting surface portion 15. Will fit.
A stepped portion 16 having a depth corresponding to the inner peripheral edge of the end surface 10a is provided on the inner peripheral surface of the inner ring 10 up to the end surface 10a on the inboard side of the inner ring 10. The inner surface of the stepped portion 16 is connected to the inner peripheral surface of the inner ring 10 on the outboard side, and an inclined surface 16a whose diameter increases in a tapered manner as it goes to the inboard side, and the inner ring 10 following the inclined surface 16a. The straight part 16b which consists of a cylindrical surface of the said depth which extends to the inboard side end of this. The inclined surface 16a is composed of a tapered surface, a curved surface, or a tapered surface and a curved surface continuous with the tapered surface as shown in the figure. The axial range W of the step portion 16 is a range that does not lie on an extension of the straight line L that forms the rolling element contact angle θ of the inner ring raceway surface 4.

On the other hand, the end portion on the inboard side of the hub wheel 9 is a plastically deformed portion 9b that is plastically deformed by caulking and is expanded in diameter. Specifically, the plastic deformation portion 9b uses a caulking punch 19 (FIG. 6) having a tip outer peripheral surface tapered and a corner chamfered between the tapered surface and the tip surface. The ring 9 is crimped into an expanded state by being pushed into the inner periphery of the inboard side end. The plastically deformed portion 9b is a non-heat treated portion so that caulking is easy. The inner peripheral surface of the plastically deformed portion 9 b is the large-diameter step portion 11 c of the through hole 11.
As shown in FIG. 3A, the plastic deformation portion 9b has a cylindrical shape before caulking, and is deformed to expand after caulking as shown in FIG. 3B. The plastically deformed portion 9b whose diameter has been deformed is engaged with the inclined surface 16a of the step portion 16 to restrict the movement of the inner ring 10 toward the inboard side. Further, the plastically deformed portion 9b after the caulking process is not in contact with the straight portion 16b of the stepped portion 16, and a gap E remains between the plastically deformed portion 9b and the stepped portion 16, and the inner ring 10 The end face 10a is not projected inboard. The inner diameter surface (hub crimped surface) 9ba of the plastically deformed portion 9b after caulking is a tapered surface that opens at the end as a part of the large diameter step portion 11c.

  In assembling the wheel bearing device to the vehicle, the stem portion 13a of the outer ring 13 serving as one joint member of the constant velocity joint 12 is inserted into the through hole 11 of the hub wheel 9 and is spline-fitted. The constant velocity joint outer ring 13 is coupled to the inner member 2 by tightening the nut 14 that is screwed into the tip of the portion 13a. At this time, the step surface 13 b facing the outboard side provided in the constant velocity joint outer ring 13 is pressed against the end surface 10 a facing the inboard side of the inner ring 10, and the inner member 2 is formed by the constant velocity joint outer ring 13 and the nut 14. Is tightened. The hub flange 9a for wheel attachment is located at the end of the hub wheel 9 on the outboard side, and a wheel (not shown) is attached to the hub flange 9a with a hub bolt 17 via a brake rotor.

According to the wheel bearing device of this configuration, the step portion 16 is provided on the inner peripheral surface of the inner ring 10 and the plastic deformation portion 9b by the caulking process of the hub wheel 9 is engaged with the step portion 16, The inner ring 10 can be prevented from coming off from the hub ring 9 due to an external force generated in the assembling process.
Since the stepped portion 16 has a very limited range of the inner periphery of the inner ring 10, the stepped portion 16 can be made as small as possible while ensuring the slip-off resistance of the inner ring 10. For this reason, there is little decrease in the area of the end surface 10a of the inner ring 10 while providing the stepped portion 16, the increase in contact surface pressure with the step surface 13b of the constant velocity joint outer ring 13 is suppressed, and the occurrence of wear and noise can be prevented. .
In particular, the caulking process of the plastic deformation portion 9b uses a caulking punch 19 whose outer peripheral surface is a tapered surface and whose corners between the tapered surface and the tip surface are chamfered. Since it is performed by pushing into the inner periphery of the inboard side end, as will be described in detail later, the caulking punch 19 does not interfere with the hub wheel 9 during caulking, and the diameter is increased to the required degree of machining. Tightening can be performed.

  This wheel bearing device is a plurality of outward angular ball bearing types, and the axial range W of the stepped portion 16 is a range that does not extend on the extended line of the straight line L that forms the rolling element contact angle θ. The deformation of the inner ring 10 due to the load can be reduced, and the life can be extended accordingly. Further, since the axial length of the step portion 16 of the inner ring 10 is short, the fitting length of the inner ring 10 with respect to the hub wheel 9 can be ensured, so that the fitting area can be secured and the occurrence of creep of the inner ring 10 can be suppressed. Can do. In this respect, the life can be extended. Moreover, since it is not necessary to lengthen the whole width dimension of the inner ring | wheel 10 in order to ensure fitting length etc., an extra space becomes unnecessary in an axial direction.

  When the plastic deformation portion 9b of the hub wheel 9 is crimped, the plastic deformation portion 9b does not come into contact with the inner diameter straight portion 16b of the inner ring step portion 16, so that the hub wheel 9 and the inner ring 10 other than the plastic deformation portion 9b An excessive load is not applied, and the deformation of the through hole 11 of the hub wheel 9 into which the stem portion 13a of the constant velocity joint 12 is fitted and the expansion of the inner ring 10 can be suppressed to be small. Thereby, adverse effects on the bearing function can be avoided. During the caulking process, the plastic deformation portion 9b of the hub wheel 9 can be easily plastically deformed along the inclined surface 16a of the inner ring step portion 16. For this reason, proper caulking can be performed, and the securing of the pull-out strength is further ensured.

  The plastic deformation portion 9b having the large-diameter step portion 11c of the through hole 11 as the inner peripheral surface is a portion having a large inner diameter and a small thickness in the hub wheel 9, and the entire volume is small, so that caulking is easy. . In addition, since the plastic deformation portion 9b is small, even when the diameter is increased, the projection height h does not become higher than necessary, and even if the step of the inner ring step portion 16 is small, the plastic deformation portion 9b is formed by the inner ring step portion 16b. It is possible not to contact the straight portion 16b. Further, since the through hole 11 has a two-stepped shape having a larger inner diameter toward the inboard side, the stem portion 13a of the constant velocity universal joint 12 is spline-fitted to the general diameter portion 11a of the through hole 11. In addition, the insertion is easy and the assembly work is easy.

  Moreover, in this wheel bearing apparatus, since the raceway surface 4 in the hub wheel 9 is a surface-treated surface obtained by quenching, a rolling life can be ensured. Since the plastic deformation portion 9b is a non-heat treated portion, it can be easily crimped. The inner ring 10 is a small part having a raceway surface 4 and the inner diameter surface of the inner ring 10 being fitted to the hub ring 9, so that the entire surface from the surface to the core is hardened by quenching as described above. Thus, the rolling life is excellent and the wear resistance of the fitting surface is excellent.

  Next, a method for caulking the plastic deformation portion 9b of the hub wheel 9 to the inner ring step portion 16 will be described with reference to FIGS. In this caulking process, first, the bearing device is placed on the cradle 18 in a posture in which the inboard side faces upward as shown in FIG. In this fixed state, as shown in FIG. 5, the tip outer peripheral surface becomes a tapered surface 19a, and a corner 19c between the tapered surface 19a and the tip surface 19b is chamfered (symbol R2: see FIG. 6). The clamping punch 19 is lowered onto the inboard side end of the hub wheel 9, and the tip end portion having the tapered surface 19a is pushed into the inner periphery of the hub wheel 9, so that the plastically deformed portion 9b of the hub wheel 9 is moved all around. Press work. The inner ring 10 pushes the caulking punch 19 with the outer diameter surface being unconstrained. At that time, the outer diameter of the plastically deformed portion 9b after caulking is adjusted by controlling the stroke in the axial direction into which the caulking punch 19 is pushed. There are the following three methods for stroke control.

FIG. 8A shows a method of controlling the stroke of the caulking punch 19 with the end face of the hub wheel 9 as the stroke reference (zero point) of the caulking punch 19. This method is suitable for controlling the degree of processing because the end surface of the hub wheel 9 that is a workpiece is used as a reference surface for control.
FIG. 8B shows a method of controlling the stroke of the crimping punch 19 with the end face 10 a of the inner ring 10 as a stroke reference (zero point) of the crimping punch 19. In this method, since the end surface 10a of the inner ring 10 that is a polished finish surface is used as a reference surface for control, highly accurate control can be performed.
FIG. 8 (C) shows the position at which the caulking punch 19 or the reference surface detection flat surface, spherical surface or conical jig is in contact with the hub wheel 9 as a stroke reference (zero point), and caulking for a fixed stroke from there. A method for controlling the stroke of the crimping punch 19 so as to lower the punch 19 will be described. In this method, since the starting point of plastic working is used as a control reference point, a stable workability can be obtained without being affected by variations in tolerances such as the inner diameter and end face position of the hub wheel 9.
In any of the control methods, the outer diameter and inner diameter of the plastic deformation portion 9b after crimping are adjusted by adjusting the axial stroke into which the crimping punch 19 is pushed. It is affected by the causes of variations in processing accuracy (base metal hardness, heat treatment range, shape and size of plastic deformation portion 9b, etc.) and caulking punch conditions (surface deterioration, attached oil condition, etc.) Therefore, the wheel bearing device can always be manufactured accurately and stably. As described above, since each control method has slightly different advantages and suitability, the most appropriate control method may be selected in accordance with various conditions such as the form and application of the bearing.

By performing press working while adjusting the stroke of the caulking punch 19 by any of the above control methods, the plastic deformation portion 9b of the hub wheel 9 is enlarged as shown in FIG. Is crimped to the inner ring step portion 16. At the time of this caulking, the outer peripheral surface portion of the front end of the caulking punch 19 becomes a tapered surface 19a, and the chamfer R2 is applied to the corner 19c between the tapered surface 19a and the front end surface 19b. The shaft required for the hub crimping surface 9ba formed in the large-diameter step portion 11c of the hub through-hole 11 is reduced by reducing the angle of the tapered surface 19a of the crimping punch 19 (see FIG. 13A). Even if the directional dimension (see FIG. 13A) becomes longer, the chamfered tip end corner portion 19c of the caulking punch 19 and the base of the hub caulking portion (the base of the large-diameter step portion 11c) 9d interfere with each other. There is nothing to do.
Further, since the punch tip corner and the hub caulking portion base 9d do not interfere with each other, the hub inner diameter surface serving as a guide surface of the stem portion 13a (see FIG. 1) of the constant velocity joint 12, that is, the intermediate diameter step of the hub through hole 11 is obtained. The guide length of the part 11b can be ensured. Alternatively, by shortening the tip length of the crimping punch 19 and increasing the tip diameter, the tip of the punch 19 comes into contact with the hub end surface 9c and the chamfered portion (see FIG. 16) during crimping, and crimping is performed. It is not possible to generate burrs.
In this way, the caulking process is performed smoothly. Also, the portion of the hub wheel 9 that becomes the plastically deformed portion 9b has a smaller inner diameter than the other portions before and after the caulking process, and has a reduced thickness. After caulking, the caulking process is completed when the caulking punch 19 is retracted from the inboard side end of the hub wheel 9 as shown in FIG.

  According to this manufacturing method, it is possible to adjust the stroke in the axial direction for pushing the caulking punch 19 in accordance with the cause of variation in machining accuracy due to the hub wheel 9 that is a workpiece and the state of the caulking punch 19. For this reason, it can always press-process stably so that the protrusion height h to the radial direction of the plastic deformation part 9b may become required height, and the inner ring | wheel omission prevention of a finished product is ensured. In this caulking process, the caulking punch 19 whose outer peripheral surface is a tapered surface 19a and whose corner 19c between the tapered surface 19a and the end surface 19b is chamfered is inserted into the inner end of the hub wheel 9 on the inboard side. Since it is performed by pushing it into the circumference in the axial direction, the caulking punch 19 does not interfere with the inner ring 10 as well as the hub ring 9 during caulking, and the diameter-enlarged caulking process to the required degree of machining is accurately performed. And can be done easily.

Is a cross-sectional view of a vehicle wheel bearing device manufactured by written that the manufacturing method in an embodiment of the present invention. It is a partial expanded sectional view of the wheel bearing device. It is an enlarged view of a hub ring plastic deformation part, an inner ring level difference part, and its peripheral part, (A) shows the state before caulking, and (B) shows the state after caulking. It is explanatory drawing which shows the pre-process of the crimping process of the bearing apparatus for wheels. It is explanatory drawing which shows the intermediate process of the crimping process of the bearing apparatus for wheels. It is an enlarged view of the X section of FIG. It is explanatory drawing which shows the completion of the crimping process of the bearing apparatus for the wheels. It is explanatory drawing which shows the stroke control of the crimping punch in the crimping process of the bearing apparatus for wheels, (A)-(C) shows a different control method, respectively. It is sectional drawing of the prior art example of the bearing apparatus for wheels. It is a partial expanded sectional view of the conventional example. It is a partial expanded sectional view of the wheel bearing apparatus which is a tentative example. It is explanatory drawing which shows the caulking process of the example of the tentative plan. (A) (B) is explanatory drawing which shows the state at the time of the caulking process in the example of the trial. (A) (B) is explanatory drawing which shows another state at the time of the caulking process in the same tentative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outer member 2 ... Inner member 3 ... Outer member raceway surface 4 ... Inner member raceway surface 5 ... Rolling element 9 ... Hub ring 9a ... Hub flange 9b ... Plastic deformation part 10 ... Inner ring 10a ... Inner ring End surface 11 ... Through hole 11a ... General diameter part 11b ... Intermediate diameter step part 11c ... Large diameter step part 11d ... Spline groove 12 ... Constant velocity universal joint 13a ... Stem part 16 of constant velocity universal joint ... Step part 16a of inner ring ... Inner ring Inclined surface 16b of stepped portion Straight portion 19 of inner diameter stepped portion Caulking punch 19a Peripheral tapered surface 19b of caulking punch Tip end surface 19c of caulking punch W angle of caulking punch W Inner ring stepped portion Axial direction range θ ... rolling element contact angle L ... straight line forming ball contact angle

Claims (4)

An inner member having an outer member having a double-row raceway surface on the inner surface, an inner member having a raceway surface facing the raceway surface, and a double-row rolling element interposed between the opposing raceway surfaces, the inner member Is a hub ring having a hub flange for wheel mounting on the outer periphery and having a through hole in the center, and an inner ring fitted to the outer periphery of the inboard side end of the hub ring. A row of raceways is formed, and a stepped portion is provided on the inner peripheral surface of the inner ring up to the end surface on the inboard side of the inner ring. The inner surface of the stepped portion is formed with a straight portion made of a cylindrical surface, and from the end portion in a shape made by an inclined surface following the inner peripheral surface of the inner ring, the only set the plastic deformation portion which engages with the inclined surface of the step portion of the inner ring by caulking of the wheel hub, the inner ring The depth of the stepped portion depends on the engagement of the plastic deformation portion of the hub wheel. Small depth Satoshi enough to prevent the omission of the inner ring in the assembly process of the vehicle, before Symbol plastically deformed portion shall not protrude from the end face of the inner ring, the stem of the outer ring of the constant velocity joint in the through hole of the hub wheel The hub ring is coupled to the outer ring of the constant velocity joint by tightening a nut that is inserted into the stem portion and screwed into the tip of the stem portion, and an end surface facing the inboard side of the inner ring is provided on the outer ring of the constant velocity joint. a method of manufacturing a wheel bearing device of the driving wheel supporting pressed against the stepped surface facing the outboard side,
The plastically deformed portion has a cylindrical shape before deformation, the diameter of the tip surface is larger than that of the through hole, the tip outer peripheral surface is a tapered surface, and the corner between the tapered surface and the tip surface is formed. Chamfered caulking punch is axially pushed into the inner circumference of the inboard side end of the hub wheel so that the diameter is expanded over the entire circumference, and the axial stroke for pushing the caulking punch is controlled. And adjusting the outer diameter and inner diameter of the plastically deformed portion after crimping.   2. The method of manufacturing a wheel bearing device according to claim 1, wherein the control of the stroke in the axial direction for pushing in the caulking punch uses the end face of the hub wheel as a stroke reference of the caulking punch.   2. The method of manufacturing a wheel bearing device according to claim 1, wherein the control of the stroke in the axial direction for pushing in the caulking punch is based on the stroke of the caulking punch on the end surface of the inner ring.   2. The axial stroke control for pushing in the caulking punch according to claim 1, wherein the position where the caulking punch is in contact with the hub wheel is used as a stroke reference of the caulking punch, and the caulking punch is axially moved from this position by a predetermined stroke. A method of manufacturing a bearing device for a wheel that moves in a direction.

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