WO2012176787A1

WO2012176787A1 - Wheel bearing device and preload-controlling method therefor

Info

Publication number: WO2012176787A1
Application number: PCT/JP2012/065690
Authority: WO
Inventors: 小森　和雄
Original assignee: Ntn株式会社
Priority date: 2011-06-20
Filing date: 2012-06-20
Publication date: 2012-12-27

Abstract

[Problem] To provide a wheel bearing device designed for improved durability that effectively limits swage cracking of the base of the swaged part of the hub ring during swaging and generation of cracks during use. [Solution] On the inner splined part (22) of a coupler ring (21), multiple spline flutes (22a) and spline ridges (22b) are alternately formed and mesh with a hub splined part (23) of the small diameter part (4b) of a hub ring (4), the hub splined part comprising multiple spline flutes (23a) and spline ridges (23b). The edge faces of the spline ridges (23b) are formed as a single arc having a prescribed radius of curvature (R). The radius of curvature (R) is set to be larger than a dimension (A) from the inner end face of the coupler ring (21) to the edge (B) of the spline ridge (R > A) and to be larger than the height (h) of the spline ridges (23b) (R > h). The internal diameter (Db) of the spline ridges (22b) is larger than the flute radius (Da) of the spline flutes (23a) and the difference in diameter ∆D is set to be 1.0 mm or less.

Description

Wheel bearing device and preload management method thereof

The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like, and more particularly to a wheel bearing device having a clutch function for switching a wheel between driving and non-driving and a preload management method thereof.

Some four-wheel drive vehicles allow front wheels or rear wheels to be selectively switched to driven wheels by the clutch function provided in the wheel bearing device. As shown in FIG. 11, such a wheel bearing device 50 with a clutch function is fitted on a hub shaft 52 that is coaxially mounted on an axle 51 of a drive train, and is fitted on the center of the hub shaft 52 in the axial direction. A double-row tapered roller bearing 53 as a rolling bearing, and a coupler ring 54 arranged in parallel with the double-row tapered roller bearing 53 in the axial direction. The wheel bearing device 50 is coaxially supported on the axle 51 by a deep groove ball bearing 55 and a needle roller bearing 56 disposed between the axle 51 and the hub shaft 52. Note that G is a gear ring that is slidable in the axial direction.

The hub shaft 52 includes a sleeve portion 57 formed coaxially with the axle 51, a flange portion 58 formed on one end side (wheel side) of the sleeve portion 57 and extending radially outward, and a sleeve And a bent portion 59 formed on the other end side (the vehicle body center side) of the portion 57 and bent outward in the radial direction. Further, a spline portion 60 in which a plurality of spline grooves (spline grooves) 60 a and a plurality of spline protrusions 60 b are alternately formed is formed on the outer peripheral surface of the sleeve portion 57 in the vicinity of the bent portion 59. The spline portion 60 is configured to mesh with an inner peripheral side spline portion 61 formed on the inner peripheral surface of the coupler ring 54. Further, a through hole (fastening hole) 58a is formed in the flange portion 58, and a wheel of a wheel as a rotating body (see FIG. 5) is obtained by passing a fastening member BO such as a bolt through the through hole (fastening hole) 58a. (Not shown).

The double-row tapered roller bearing 53 includes an inner ring 62, an outer ring 63, and

tapered rollers

64 and 65 as rolling elements that are interposed between the inner and

outer rings

62 and 63 and are arranged in two rows in the axial direction. Yes.
Specifically, the inner ring 62 is divided into a first inner ring member 66 having a first track portion 66a and a second inner ring member 67 having a second track portion 67a. The first inner ring member 66 and the second inner ring member 67 are in contact with each other, and the end surface 66b on the first inner ring member 66 side is in contact with the root portion of the flange portion 58 of the hub shaft 52. The end surface 67 b on the inner ring member 67 side of 2 is in contact with the end surface of the coupler ring 54. Therefore, the inner ring 62 (the first inner ring member 66 and the first inner ring member 66 and the double ring tapered roller bearing 53) is formed between the root portion of the flange portion 58 of the hub shaft 52 and the bent portion 59 of the hub shaft 52. The second inner ring member 67) is fixed and is configured so as not to rotate with respect to the hub shaft 52.

On the other hand, the outer ring 63 has a first raceway portion 63a and a second raceway portion 63b, and a flange portion 63c extending outward in the radial direction. The flange portion 63c is attached and fixed to a steering knuckle (suspension device) or the like of the vehicle body. Reference numeral 68 denotes a seal member.

The coupler ring 54 is annular as a whole, and is arranged side by side in the axial direction so as to contact the other end side surface (end surface 67b on the second inner ring member 67 side) of the double row tapered roller bearing 53. An outer peripheral side spline portion 69 in which a plurality of spline grooves (spline grooves) 69a and a plurality of spline protrusions 69b are alternately formed is formed on the outer peripheral surface of 54. The outer peripheral side spline portion 69 is configured to mesh with the spline portion G1 of the gear ring G.

Then, referring also to FIG. 12, the inner peripheral edge portion of the inner peripheral side spline portion 61 of the coupler ring 54 on the other end side in the axial direction of the spline protrusion 61b is chamfered into a curved surface so that the other end side surface is chamfered. Part 70. The other end side chamfer 70 is formed so that the entirety thereof is positioned on the outer side in the axial direction than the spline part 60 of the hub shaft 52. Specifically, the distance from the side surface 71 on the other end side in the axial direction of the coupler ring 54 to the one end portion (on the spline portion 60 side of the hub shaft 52) 71a of the other end side chamfer 70 is L, and the axial direction of the coupler ring 54 When the distance from the side surface 71 on the other end side to the end point portion 60c of the spline groove (spline groove) 60a of the spline portion 60 of the hub shaft 52 is X, the distance L is formed to be smaller than the distance X. Yes. As a result, when the other axial end of the hub shaft 52 is bent and pressed, the bending radius of the bent portion can be increased, so that a crack (caulking crack) occurs in the root portion of the bent portion 59. Can be effectively suppressed (see, for example, Patent Document 1).

Japanese Patent No. 4466302

In this conventional wheel bearing device 50, when the other axial end portion of the hub shaft 52 is bent and pressed, the bending radius of the bent portion can be increased, so that the root portion of the bent portion 59 is cracked. It is said that the occurrence can be effectively suppressed. However, when the caulking process is actually performed, the root portion of the bent portion 59 has a shape along the shape of the side surface chamfered portion 70 of the coupler ring 54, and as shown by the broken line in the figure, the bent portion 59 is bent. The root portion of the portion 59 has a V shape in which stress is easily concentrated. As a result, the strength of the bent portion 59 may not only fluctuate, but the caulking strength may decrease.

The present invention has been made in view of such circumstances, and caulking cracks or cracks occur during use at the root of the caulking portion (folded portion) of the hub wheel (hub shaft) during caulking. An object of the present invention is to provide a wheel bearing device that effectively suppresses the above and improves durability.

Another object of the present invention is to provide a coupler ring that is soft to some extent, thereby preventing excessive stress from being generated in the coupler ring, increasing the strength of the coupler ring, suppressing variations, and maintaining stable preload management. It is providing the wheel bearing apparatus which can perform, and its preload management method.

In order to achieve such an object, the invention according to claim 1 of the present invention includes an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a wheel attachment for attaching a wheel to one end. A hub wheel having a flange integrally formed with a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring via a predetermined shimiro An inner member having a double-row inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and a cage between both rolling surfaces of the inner member and the outer member. A coupler ring having an inner peripheral spline portion and an outer peripheral spline portion is externally fitted to an end portion of the small diameter step portion of the hub wheel, The inner ring is formed by a caulking portion formed by plastically deforming the end of the step portion radially outward. In the wheel bearing device fixed in the axial direction via the coupler ring, the inner peripheral spline portion of the coupler ring is formed with a plurality of spline concave stripes and a plurality of spline convex stripes alternately. The hub spline formed by a plurality of spline ridges and a plurality of spline ridges alternately formed on the outer peripheral surface on the inner side of the small-diameter step portion meshes with the end surface of the spline ridge of the hub spline portion with a predetermined curvature. A radius of curvature R is larger than a dimension A (R> A) from the inner side end face of the coupler ring to the edge of the spline ridge, and It is set to be larger than the height h of the spline ridge (R> h).

Thus, the coupler ring formed with the inner peripheral spline portion and the outer peripheral spline portion is fitted on the end portion of the small diameter step portion of the hub wheel, and the end portion of the small diameter step portion is plastically deformed radially outward. In the wheel bearing device in which the inner ring is fixed in the axial direction via the coupler ring by the formed caulking portion, the inner peripheral spline portion of the coupler ring is formed with a plurality of spline grooves and a plurality of spline protrusions alternately. Meshed with a hub spline portion composed of a plurality of spline ridges and a plurality of spline ridges formed alternately on the outer peripheral surface on the inner side of the small-diameter step portion of the hub wheel, and the spline ridges of the hub spline portion The end face is formed by a single arc having a predetermined radius of curvature R, and this radius of curvature R is larger than the dimension A from the end face on the inner side of the coupler ring to the edge of the spline ridge. (R> A) and larger than the height h of the spline ridge (R> h), the root portion of the caulking portion after caulking is large and rounded. Therefore, it is possible to prevent a V shape from being easily concentrated in stress. Therefore, it is possible to provide a wheel bearing device that effectively suppresses the occurrence of caulking cracks or cracks during use at the base of the caulking portion of the hub wheel during caulking, and improves durability. it can.

Preferably, when the groove diameter of the spline groove of the hub spline part is Da and the inner diameter of the spline protrusion of the inner peripheral spline part in the coupler ring is Db as in the invention described in claim 2, this spline If the inner diameter Db of the ridge is larger than the groove diameter Da of the spline groove of the hub spline portion, the difference ΔD = (Db−Da) is set to be 1.0 mm or less. There is no fluctuation in the tightening strength, and a decrease in the strength of the crimped portion can be prevented.

According to a third aspect of the present invention, a tapered surface is formed on at least the inner diameter of the inner end of the spline ridges in the inner peripheral spline of the coupler ring, and the starting point of the tapered surface However, if it is arranged within the range of the edge of the spline ridge of the hub spline part and the bottom of the spline ridge, the caulking part can easily follow the inner diameter of the coupler ring during caulking. It is possible to prevent the portion from being V-shaped where stress is easily concentrated.

Further, as in the invention according to claim 4, a tapered chamfered portion is formed on the inner diameter of at least the inner end of the both ends of the coupler ring, and a radial dimension H1 of the chamfered portion is: If the height of the spline ridge of the inner peripheral spline portion is set to be larger than H0 (H1 ≧ H0), the coupler ring is engaged with the hub spline portion and the caulking portion It is difficult for the spline ridge to be formed due to the root portion entering, and even when a load is applied to the caulking portion, it is possible to prevent the stress from concentrating on the spline ridge and reducing the strength.

Further, as in the fifth aspect of the invention, a tapered chamfered portion may be formed at least at the end on the inner side of both end portions of the spline recess in the inner peripheral spline portion of the coupler ring. Further, as in the invention described in claim 6, an arc-shaped chamfered portion having a predetermined radius of curvature is provided at least at the inner side end portion of both end portions of the spline recess in the inner peripheral spline portion of the coupler ring. It may be formed. Thereby, the volume of a spline protruding item | line can be enlarged and the stress concentration to this part can be avoided.

Further, as in the seventh aspect of the present invention, if the spline groove on the inner peripheral spline portion of the coupler ring is stopped at the inner end to form a non-groove portion, Spline ridges are less likely to be formed at the base of the part, and stress concentration can be avoided.

Further, as in the invention according to claim 8, the coupler ring is made of a steel material having a carbon content of medium carbon steel or less, and is hardened to the core portion by quenching, so that the outer peripheral spline portion and the inner peripheral spline portion are If the hardness is set to the same level, it is possible to prevent excessive stress from being generated in the coupler ring during the caulking process, thereby preventing deformation and microcracks, and the coupler ring is plastically deformed by caulking. Since it is difficult, the amount of elastic deformation can be measured with high accuracy, high accuracy, and stable preload management can be performed while suppressing variations.

Preferably, as in the invention according to claim 9, if the surface hardness of the coupler ring has a hardness difference of at least 130 HV with respect to the hub wheel, only the outer peripheral spline portion and the inner peripheral spline portion of the coupler ring. In addition, the entire coupler ring can secure the desired strength, and when forming the crimped portion, the end of the small diameter step of the hub wheel can be plastically deformed radially outward, It is possible to prevent a caulking defect such as a micro crack from occurring.

Further, as in the invention described in claim 10, when the coupler ring is contained in the range of 0.09 to 0.12 wt% Cr and the surface hardness is set in the range of 392 to 600 HV, the strength of the coupler ring is high. Thus, it is possible to prevent deformation and microcracks from occurring when excessive stress is generated in the caulking process.

Further, as in the invention described in claim 11, if the coupler ring is made of a steel material made of carbon of 0.15 to 0.45 wt%, a spline portion having an appropriate hardness can be obtained, and a desired value can be obtained. The strength of the coupler ring can be ensured.

Further, as in the invention described in claim 12, when the coupler ring is made of chromium steel containing 0.12 to 0.2 wt% of Cr and is hardened by quenching and tempering, the strength of the coupler ring is increased. In the caulking step, it is possible to prevent deformation and micro cracks from being generated due to excessive stress in the coupler ring.

Further, as in the invention described in claim 13, if the coupler ring is formed of chromium molybdenum steel containing 0.15 to 0.3 wt% of Mo, brittleness can be suppressed, and caulking work can be performed. It is possible to reliably prevent occurrence of minute cracks.

Further, as in the invention described in claim 14, if the tooth bottom of the outer peripheral spline portion of the coupler ring is formed in an arc shape having a predetermined radius of curvature, the force during caulking is dispersed, and the tooth bottom Can be prevented.

Further, as in the invention described in claim 15, an outer joint member constituting a constant velocity universal joint is coupled to the inner member, and the outer peripheral surface of the outer joint member is the same as the outer peripheral spline portion of the coupler ring. An axle side spline portion having the same diameter and the same shape is formed, and the outer peripheral spline portion and the axle side spline portion are arranged coaxially with each other, and the drive side is slidable in the axial direction on the axle side spline portion. The inner peripheral spline part of the gear ring may be engaged.

Further, as in the invention described in claim 16, the hub wheel is made of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon, and is formed from the base portion on the inner side of the wheel mounting flange to the small diameter step portion. If a predetermined hardened layer is formed in the range of 58 to 64 HRC by induction hardening, and the caulking portion is an unquenched portion with the surface hardness after forging, caulking is performed. This makes it easy to prevent the occurrence of microcracks during processing, and has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange, thereby improving the durability of the hub wheel.

According to a seventeenth aspect of the present invention, the method invention according to claim 17 integrally has a vehicle body mounting flange to be attached to the knuckle constituting the suspension device on the outer periphery, and a double row outer rolling surface is integrated on the inner periphery. An outer member formed integrally with a wheel mounting flange for attaching a wheel to one end, and a hub wheel having a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and the hub wheel An inner member formed of at least one inner ring press-fitted into the small-diameter step portion through a predetermined scissors, and formed with a double-row inner rolling surface facing the double-row outer rolling surface on the outer periphery; and In a preload management method for a wheel bearing device comprising a double row rolling element that is rotatably accommodated between a rolling surface of an inner member and the outer member via a cage, the hub wheel includes: Addition formed by plastically deforming the end of the small diameter step part radially outward The inner ring is fixed in the axial direction with a predetermined bearing preload applied through a ring-shaped coupler ring by a portion, and the bearing clearance before caulking is measured, and the reference surface of the coupler ring before and after caulking , Measure the amount of change in height from the bearing clearance before caulking, and calculate the amount of change in height using a regression equation in which the relationship between the amount of elastic deformation and the amount of clearance reduction has been confirmed in advance. Subtract the clearance reduction amount to calculate the bearing clearance after crimping.

In this way, the height from the reference surface of the coupler ring before and after caulking is measured, and the amount of change in the height is determined by a regression equation in which the relationship between the amount of elastic deformation and the amount of clearance reduction is confirmed in advance. Since the bearing clearance after caulking is calculated by subtracting this clearance reduction amount from the bearing clearance before caulking, even if the bearing clearance after caulking is negative, it is indirectly preloaded. The amount can be controlled stably.

The wheel bearing device according to the present invention integrally has an outer member integrally formed with a double row outer rolling surface on the inner periphery, and a wheel mounting flange for mounting the wheel on one end, and on the outer periphery. The hub wheel is formed with a cylindrical small-diameter step portion extending in the axial direction, and at least one inner ring press-fitted into the small-diameter step portion of the hub ring through a predetermined shimoshiro. An inner member in which a double row of inner rolling surfaces facing the running surface is formed, and a compound member that is rotatably accommodated via a cage between both rolling surfaces of the inner member and the outer member. A coupler ring formed with an inner peripheral spline portion and an outer peripheral spline portion is fitted on the end portion of the small diameter step portion of the hub wheel, and the end portion of the small diameter step portion is radially outward. The inner ring passes through the coupler ring by a caulking portion formed by plastic deformation in the direction of In the wheel bearing device fixed in the direction, the inner peripheral spline portion of the coupler ring includes a plurality of spline concave stripes and a plurality of spline convex stripes alternately formed on the inner side of the small diameter step portion of the hub wheel. A hub spline portion composed of a plurality of spline ridges and a plurality of spline ridges alternately formed on the outer peripheral surface meshes with each other, and the end surface of the spline ridge of the hub spline portion has a single radius of curvature R. An arc is formed, and this radius of curvature R is larger than the dimension A (R> A) from the inner end surface of the coupler ring to the end edge of the spline ridge, and the height h of the spline ridge is h. Is set so as to be larger (R> h), so that the root portion of the crimped portion after crimping has a large rounded shape, and a V-shape that easily concentrates stress. It is possible to prevent. Therefore, it is possible to provide a wheel bearing device that effectively suppresses the occurrence of caulking cracks or cracks during use at the base of the caulking portion of the hub wheel during caulking, and improves durability. it can.

Further, the preload management method for a wheel bearing device according to the present invention integrally has a vehicle body mounting flange for mounting on a knuckle that constitutes a suspension device on the outer periphery, and a double row outer rolling surface is integrated on the inner periphery. An outer member formed integrally with a wheel mounting flange for attaching a wheel to one end, and a hub wheel having a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and the hub wheel An inner member formed of at least one inner ring press-fitted into the small-diameter step portion through a predetermined scissors, and formed with a double-row inner rolling surface facing the double-row outer rolling surface on the outer periphery; and In a preload management method for a wheel bearing device comprising a double row rolling element that is rotatably accommodated between a rolling surface of an inner member and the outer member via a cage, the hub wheel includes: The end of the small diameter step was formed by plastic deformation radially outward. The inner ring is fixed in the axial direction with a predetermined bearing preload applied via a ring-shaped coupler ring by a tightening portion, and the bearing clearance before caulking is measured, and the reference of the coupler ring before and after caulking Measure the height from the surface, and calculate the amount of change in the height using a regression equation in which the relationship between the amount of elastic deformation and the amount of clearance reduction has been confirmed in advance. Since the bearing clearance after caulking is calculated by subtracting the clearance reduction amount, the preload amount can be indirectly and stably managed even if the bearing clearance after caulking is negative.

It is a longitudinal section showing a 1st embodiment of a bearing device for wheels concerning the present invention. It is a longitudinal cross-sectional view which shows the bearing part of FIG. (A) is a principal part enlarged view which shows the crimping part of FIG. 1, (b) is a principal part enlarged view which shows a caulking before the same as the above. (A) is sectional drawing which shows the modification of the coupler ring of FIG. 3, (b) is sectional drawing which shows another modification. It is a principal part enlarged view which shows before caulking using the coupler ring of Fig.4 (a). (A)-(c) is sectional drawing which shows the other modification of the coupler ring of Fig.4 (a). It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a principal part enlarged view which shows the crimping part of FIG. (A) is sectional drawing of the coupler ring which concerns on this invention, (b) is sectional drawing which shows the modification of (a). It is a longitudinal cross-sectional view which shows before the caulking of the wheel bearing apparatus which concerns on this invention. It is a longitudinal cross-sectional view which shows the conventional wheel bearing apparatus. It is a principal part enlarged view of FIG.

An outer member that integrally has a vehicle body mounting flange for attaching to a knuckle on the outer periphery, and has a tapered double-row outer rolling surface integrally formed on the inner periphery, and a wheel on one end A hub wheel integrally having a wheel mounting flange for mounting a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and press-fitted into the small-diameter step portion of this hub ring via a predetermined shimiro, An inner member composed of a pair of inner rings having a tapered inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and between both rolling surfaces of the inner member and the outer member A double-row tapered roller accommodated in a rollable manner via a cage, and a coupler ring having an inner peripheral spline portion and an outer peripheral spline portion formed on the end of the small-diameter step portion of the hub wheel is externally fitted. The end of the small diameter step is plastically deformed radially outward. In the wheel bearing device in which the inner ring is fixed in the axial direction through the coupler ring by the crimped portion, the inner peripheral spline portion of the coupler ring has a plurality of spline grooves and a plurality of spline protrusions alternately. And a hub spline portion formed of a plurality of spline recesses and a plurality of spline projections formed alternately on the outer peripheral surface on the inner side of the small-diameter step portion of the hub wheel, and the spline of the hub spline portion The end face of the ridge is formed by a single arc having a predetermined radius of curvature R, and this radius of curvature R is larger than the dimension A from the end face on the inner side of the coupler ring to the edge of the spline ridge ( R> A), set to be larger than the height h of the spline ridge (R> h), and the groove diameter of the spline groove of the hub spline portion Da, when the inner diameter of the spline ridge of the inner peripheral spline portion in the coupler ring is Db, the inner diameter Db of the spline ridge is larger than the groove diameter Da of the spline ridge of the hub spline portion. The difference ΔD = (Db−Da) is set to be 1.0 mm or less.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device according to the present invention, FIG. 2 is a longitudinal sectional view showing a bearing portion of FIG. 1, and FIG. Fig. 4 (b) is an enlarged view of the main part showing the fastening part, Fig. 4 (a) is a cross-sectional view showing a modification of the coupler ring of Fig. 3, and Fig. 4 (b) is the same. FIG. 5 is a cross-sectional view showing another modification, FIG. 5 is an enlarged view of a main part before caulking using the coupler ring of FIG. 4A, and FIGS. 6A to 6C are FIG. It is sectional drawing which shows the other modification of the coupler ring of). In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side in FIG. 1), and the side closer to the center is referred to as the inner side (right side in FIG. 1).

The wheel bearing device includes an inner member 1 and an outer member 2, and double row rolling elements (conical rollers) 3 and 3 accommodated between both

members

1 and 2 so as to be freely rollable. The inner member 1 includes a hub ring 4 and a pair of

inner rings

5 and 7 plastically coupled to the hub ring 4.

The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and has a cylindrical shape that extends in the axial direction from the wheel mounting flange 6 to the outer periphery via a shoulder portion 4a. The small diameter step 4b is formed. Further, hub bolts 6 a for fixing the wheels at the circumferentially equidistant positions of the wheel mounting flange 6 are planted.

The pair of

inner rings

5 and 7 each have a tapered inner rolling surface 5a formed on the outer periphery, and are press-fitted into the small-diameter step portion 4b of the hub ring 4 via a predetermined squeeze. Then, as shown in an enlarged view in FIG. 2,

large collar portions

5b and 7b for guiding the rolling element 3 are formed on the large diameter side of the inner rolling surface 5a, and the rolling element 3 is formed on the small diameter side. Of the back-to-back type that is set in a state in which the

small edge portions

5c and 7c are formed to prevent the falling off of the inner ring 5 and the

small end surfaces

5d and 7d (front end surfaces) of the

inner rings

5 and 7 are abutted with each other. Conical roller bearings are configured.

The outer member 2 integrally has a vehicle body mounting flange 2b to be attached to a knuckle (not shown) constituting a suspension device on the outer periphery, and has a taper-shaped double-row outer roll that opens outward on the inner periphery. The running surfaces 2a and 2a are integrally formed. And the double

row rolling elements

3 and 3 are accommodated so that rolling is possible via the holder | retainer 8 between both rolling surfaces. An annular groove 9 is formed on the outer diameter surface fitted into the knuckle, and an elastic ring 10 such as an O-ring is attached to the annular groove 9. Thereby, the airtightness of the fitting part of a knuckle and the outward member 2 can be improved.

The hub wheel 4 is formed of medium-high carbon steel (carbon steel for SC system mechanical structure of JIS standard) containing carbon of 0.40 to 0.80 wt% such as S53C, and has a high frequency extending from the shoulder portion 4a to the small diameter step portion 4b. A predetermined hardened layer having a surface hardness in the range of 50 to 64 HRC is formed by quenching. Further, the

inner rings

5 and 7 and the rolling element 3 are made of high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core part by quenching. The caulking portion 11 described later is an unquenched portion with the surface hardness after forging. This facilitates caulking and prevents the occurrence of microcracks during processing, and has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 6, and the durability of the hub wheel 4. Improves.

The outer member 2 is formed of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, similar to the hub wheel 4, and at least the double row

outer raceway surfaces

2a and 2a are formed on the surface by induction hardening. A predetermined curing process is performed in the range of 58 to 64 HRC.

Seals

12 and 12 are attached to the opening of the annular space formed between the outer member 2 and the

inner rings

5 and 7, leakage of the lubricating grease sealed inside the bearing, rainwater, dust, etc. from the outside Is prevented from entering the inside of the bearing.

The seal 12 is constituted by a so-called pack seal composed of a slinger 39 and an annular seal plate 40 arranged to face each other. Slinger 39 is an austenitic stainless steel sheet (JIS standard SUS304 series, etc.), a ferritic stainless steel sheet (JIS standard SUS430 series, etc.), or a rust-proof cold rolled steel sheet (JIS standard SPCC system, etc.). And a cylindrical portion 39a having a substantially L-shaped cross section by press working and press-fitted into the large collar portion 7b (5b) of the

inner rings

5, 7, and a standing plate portion extending radially outward from the cylindrical portion 39a 39b.

On the other hand, the seal plate 40 includes a cored bar 41 fitted into the end portion of the outer member 2 and a seal member 42 integrally joined to the cored bar 41 by vulcanization adhesion. The cored bar 41 is formed in a substantially L-shaped cross section by press working from an austenitic stainless steel plate or a cold-rolled steel plate that has been rust-proofed.

The seal member 42 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and integrally includes a pair of side lips 42a and 42b extending obliquely outward in the radial direction and a grease lip 42c extending obliquely inward of the bearing. Have. The side lips 42a and 42b are in sliding contact with the side surface of the standing plate portion 39b of the slinger 39 via a predetermined axial shimiro, and the grease lip 42c is slid onto the cylindrical portion 39a of the slinger 39 via a predetermined radial shimillo. It touches. As the material of the seal member 42, in addition to the exemplified NBR, for example, HNBR (hydrogenated acrylonitrile butadiene rubber), EPDM (ethylene propylene rubber), etc. having excellent heat resistance, heat resistance, chemical resistance, etc. Examples thereof include ACM (polyacrylic rubber), FKM (fluororubber), and silicon rubber, which are excellent in the above.

In this embodiment, the rotational speed sensor 13 is inserted between the double row

outer rolling surfaces

2a, 2a of the outer member 2 into a sensor insertion hole 14 formed so as to penetrate in the radial direction. This rotational speed sensor 13 incorporates a magnetic detecting element such as a Hall element, a magnetoresistive element (MR element) or the like that changes its characteristics according to the flow direction of magnetic flux, and a waveform shaping circuit that adjusts the output waveform of this magnetic detecting element. The synthetic resin is integrally molded by injection molding. And it has the shaft-shaped insertion part 13a inserted in the sensor insertion hole 14, and the non-insertion part 13b located in the exterior of the outer member 2. As shown in FIG. An annular groove 15 is formed on the outer periphery of the insertion portion 13a, and an elastic ring 16 made of an O-ring or the like is attached to the annular groove 15. Moreover, the non-insertion part 13b is formed in the shape seated on the sensor attachment part 17 of the outer member 2, and is fastened via the attachment piece (not shown) extended to a side.

On the other hand, a pulsar ring 18 facing the rotational speed sensor 13 via a predetermined radial clearance (air gap) is fixed to the outer periphery of the outer ring inner ring 5 on the small flange portion 5c side. The pulsar ring 18 is formed in the shape of a spur gear composed of an uneven portion 18a. Thereby, the direction of the magnetic field alternately changes on the circumference along with the rotation of the hub wheel 4, and the rotational speed of the wheel can be detected via the rotational speed sensor 13.

Further, as shown in FIG. 1, the integration of the hub wheel 4 and the

inner rings

5 and 7 is achieved by pressing the pair of

inner rings

5 and 7 into the small-diameter step portion 4b of the hub wheel 4 through a predetermined shimiro, This is performed by a caulking portion 11 formed by plastically deforming an end portion of the small diameter step portion 4b radially outward. Here, the double-row tapered roller bearing in which the rolling element 3 is a tapered roller is illustrated. However, the wheel bearing device according to the present invention is not limited to this. For example, although not illustrated, a ball is used for the rolling element. It may be composed of double row angular contact ball bearings.

Further, on the inner periphery of the hub wheel 4, a shaft portion of an outer joint member constituting a constant velocity universal joint (not shown) is rotatably supported through rolling

bearings

19 and 20. Out of these rolling

bearings

19 and 20, the outer side rolling bearing 19 is a deep groove ball bearing, and the inner side rolling bearing 20 is a shell needle roller bearing.

Between the inner ring 7 on the inner side and the caulking portion 11 of the hub ring 4, a coupler ring 21 that is a ring-shaped member is provided. That is, the inner ring 7 is fixed to the hub ring 4 via a coupler ring (gear member) 21. The coupler ring 21 is made of chromium steel such as SCr420, and is hardened in the range of 40 to 55 HRC (392 to 600 HV) to the core portion by quenching (quenching and tempering). Thus, compared to the hub wheel 4 made of S53C or the like, the amount of Cr (chrome) is approximately 0.12 to 0.2 wt%, whereas the amount of Cr in the coupler ring 21 is approximately 0.9 to 1.2 wt%. As a result, the tenacity increases and a hardness difference of about 132 to 340 HV with respect to the surface hardness 260 HV of the crimped portion 11 can be obtained, and a desired strength can be ensured. In addition, as the material of the coupler ring 21, by using chromium molybdenum steel to which Mo (molybdenum) is added approximately 0.15 to 0.3 wt%, brittleness can be suppressed, and during the caulking process. Generation of micro cracks can be reliably prevented.

The coupler ring 21 is fixed in contact with the large end surface 7e of the inner ring 7 as shown in an enlarged view in FIG. Both the inner peripheral surface and the outer peripheral surface of the coupler ring 21 are provided with spline portions, and among these, the inner peripheral spline portion 22 is formed with a plurality of spline recesses 22a and a plurality of spline protrusions 22b alternately. In addition, the hub spline portion 23 is engaged with a hub spline portion 23 composed of a plurality of spline recesses 23a and a plurality of spline protrusions 23b formed alternately on the inner peripheral surface of the small-diameter step portion 4b of the hub wheel 4.

The coupler ring 21 is pressed toward the inner side inner ring 7 by the crimping pressure from the crimping portion 11 that contacts the inner side end surface 21a. Further, the coupler ring 21 is connected to the inner side inner ring 7 and the inner side inner ring 7. The adjacent outer ring 5 on the outer side is pressed toward the shoulder 4 a of the hub ring 4. In this way, the clamping ring 21 and the pair of

inner ring members

5 and 7 are securely fixed to the hub ring 4 by the crimping pressure acting from the crimping portion 11.

On the outer peripheral surface of the constant velocity universal joint in the vicinity of the coupler ring 21, an axle side spline portion (indicated by a two-dot chain line in the figure) 25 having the same diameter and the same shape as the outer peripheral spline portion 24 of the coupler ring 21 is provided. Yes. The outer peripheral spline part 24 and the axle side spline part 25 are in a coaxial relationship with each other. The axle-side spline portion 25 meshes with an inner peripheral spline portion 26a of a gear ring (indicated by a two-dot chain line in the figure) 26 that can slide in the axial direction. Here, when the gear ring 26 moves to the outer side, it is engaged with both the axle-side spline portion 25 of the constant velocity universal joint and the outer peripheral spline portion 24 of the coupler ring 21, and thereby the driving force of the constant velocity universal joint is increased. It is transmitted to the hub wheel 4. On the other hand, when the gear ring 26 moves to the inner side, the gear ring 26 is engaged with the axle side spline portion 25 but is not engaged with the outer peripheral spline portion 24. As described above, the gear ring 26 is slid in the axial direction, thereby enabling switching to intermittently drive the hub wheel 4. Although not specifically shown, the gear ring 26 is slid by a sliding mechanism using appropriate power means such as air or hydraulic pressure.

Here, as shown in FIG. 3B, the end surface of the spline protrusion 23b of the hub spline portion 23, that is, the end edge B of the spline protrusion 23b of the hub spline portion 23, and the bottom C of the spline recess 23a, Is formed by a single arc having a predetermined radius of curvature R. For this reason, the root part of the caulking part 11 after the caulking process has a rounded shape, and it is possible to prevent a stress-concentrated V-shape. The radius of curvature R is larger than the dimension A from the inner end surface 21a of the coupler ring 21 to the edge B of the spline protrusion 23b (R> A), and from the height h of the spline protrusion 23b. Is set to be larger (R> h). In this way, by increasing the radius of curvature R to some extent, it becomes possible to prevent the root portion of the crimped portion 11 after the crimping process from being rounded, and to prevent a V-shape that is more likely to concentrate stress. it can. Further, when the groove diameter of the spline groove 23a of the hub spline portion 23 is Da and the inner diameter of the spline protrusion 22b of the inner peripheral spline portion 22 of the coupler ring 21 is Db, the inner diameter Db of the spline protrusion 22b is the spline groove. It is larger than the groove diameter Da of 23a, and the diameter difference ΔD is set to be 1.0 mm or less (ΔD = (Db−Da) ≦ 1.0 mm). Thereby, while ensuring the thickness of the base part of the caulking part 11 after caulking, it can prevent that it becomes V shape which is easy to concentrate stress. Therefore, it is possible to provide a wheel bearing device that effectively suppresses the occurrence of caulking cracks and cracks during use at the base portion of the caulking portion 11 of the hub wheel 4 during caulking, and improves durability. be able to.

In this embodiment, the dimension A is set in the range of 2.5 to 3.0 mm, and the radius of curvature R is set to R3 to 7. Incidentally, in the caulking test conducted by the present applicant, in the sample sample in which the radius difference ΔD = 0.90 mm and the curvature radius of the end surface of the spline protrusion 23b of the hub spline portion 23 is composed of R3 to 7, The root portion of the caulking portion 11 was not V-shaped, there was no variation in caulking strength, and no decrease in strength was observed. On the other hand, in the sample product in which the diameter difference ΔD = 1.70 mm and the curvature radius of the end surface of the spline protrusion 23b of the hub spline portion 23 is R0.8, the crimping strength fluctuated and the strength decreased.

FIG. 4A shows a modification of the coupler ring 21 described above. In addition, the same code | symbol is attached | subjected to the site | part which has the same site | part or the same function as embodiment mentioned above, and detailed description is abbreviate | omitted. The coupler ring 27 is provided with spline portions on the inner peripheral surface and the outer peripheral surface, and the inner peripheral spline portion 28 is formed with a plurality of spline grooves 28a and a plurality of spline protrusions 28b alternately. And the taper surface 29 is formed in the internal diameter of the both ends of this spline protruding item | line 28b, and the edge part (caulking part side of a hub ring) at least on the inner side.

FIG. 5 is an enlarged view of a main part before caulking using this coupler ring 27. The starting point T of the tapered surface 29 is within the arc-shaped end surface of the spline ridge 23b of the hub spline part 23 described above. That is, it is arranged within the range of the edge B of the spline protrusion 23b of the hub spline portion 23 and the bottom C of the spline recess 23a. As a result, the caulking portion 11 can easily follow the inner diameter of the coupler ring 27 during caulking processing, and the root portion can be prevented from becoming a V shape in which stress is easily concentrated.

FIG. 4B shows another modification of the coupler ring 21 described above. The coupler ring 30 is provided with spline portions on the inner peripheral surface and the outer peripheral surface, and a tapered chamfered portion 31 is formed on the inner diameter of at least the inner end portion (the caulking portion side of the hub wheel). . The radial dimension H1 of the chamfered portion 31 is set to be larger than the height H0 of the spline protrusion 22b of the inner peripheral spline portion 22 (H1 ≧ H0). In a state where the coupler ring 30 is engaged with the hub spline portion 23, when the root portion of the caulking portion 11 enters the spline recess 22a to form a spline protrusion, and when a load is applied to the caulking portion 11, this spline There is a possibility that stress is concentrated on the ridges and the strength is lowered. However, as in the present embodiment, a tapered chamfered portion is formed on the inner diameter of the inner end of the coupler ring 30 on the side of the caulking portion of the hub ring 4. 31 is formed, and the dimension H1 in the radial direction of the chamfered portion 31 is set to be larger than the height H0 of the spline protrusion 22b of the inner peripheral spline portion 22, so that the spline is formed at the root portion of the crimping portion 11. It is difficult to form the ridges, and stress concentration can be avoided.

FIGS. 6A to 6C show other modified examples of the coupler ring 21 described above. The coupler ring 32 shown in (a) is provided with spline portions on the inner peripheral surface and the outer peripheral surface, and a tapered chamfered portion 32a is formed at least on the inner end of the spline recess 33a of the inner peripheral spline portion 33. Is formed. As a result, the coupler ring 34 is provided with spline portions on the inner peripheral surface and the outer peripheral surface, and at least a predetermined end portion on the inner side of the spline recess 35a of the inner peripheral spline portion 35 is provided. An arc-shaped chamfer 34a having a radius of curvature r is formed. As described above, the

chamfered portions

32a and 34a are formed at least on the inner end of the spline

concave stripes

33a and 35a, so that the volume of the spline convex stripes 22b can be increased, and stress concentration on these portions can be reduced. It can be avoided.

The coupler ring 36 shown in (c) is provided with spline portions on the inner peripheral surface and the outer peripheral surface, and the spline recesses 37a of the inner peripheral spline portion 37 are stopped at the end on the inner side to form a non-groove portion 38. Has been. This non-groove portion 38 makes it difficult for spline ridges to be formed at the root of the caulking portion 11 during caulking, and stress concentration can be avoided.

FIG. 7 is a longitudinal sectional view showing a second embodiment of the wheel bearing device according to the present invention, FIG. 8 is an enlarged view of a main part showing the caulking portion of FIG. 7, and FIG. 9A is the present invention. Sectional drawing of the coupler ring which concerns on this, (b) is sectional drawing which shows the modification of (a), FIG. 10 is a longitudinal cross-sectional view which shows before caulking of the wheel bearing apparatus which concerns on this invention. The present embodiment is basically the same as the above-described embodiment (FIG. 1) except that the configuration of the coupler ring is partially different, and other parts or parts having the same parts or the same functions as the above-described embodiments. Are denoted by the same reference numerals, and detailed description thereof is omitted.

This wheel bearing device is used on the drive wheel side, and includes an inner member 1 and an outer member 2, and double-row

tapered rollers

3 and 3 accommodated between both

members

1 and 2 so as to roll freely. Yes. The inner member 1 includes a hub ring 4 and a pair of

inner rings

5 and 7 plastically coupled to the hub ring 4.

The outer member 2 integrally has a vehicle body mounting flange 2b on the outer periphery, and is integrally formed with tapered double-row outer rolling surfaces 2a and 2a that are opened outward on the inner periphery. The double-row

tapered rollers

3 and 3 are accommodated between the rolling surfaces via a cage 8 so as to freely roll.

Here, as shown in an enlarged view in FIG. 8, the inner ring 7 is fixed to the hub wheel 4 in the axial direction by the caulking portion 11 via a ring-shaped coupler ring 43. The coupler ring 43 is formed with an outer peripheral spline portion (gear portion) 43a and an inner peripheral spline portion 43b, and the inner peripheral spline portion 43b is formed on the outer peripheral surface on the inner side of the small-diameter step portion 4b of the hub wheel 4. Is engaged with the hub spline portion 23 formed. The coupler ring 43 is pressed toward the inner ring 7 by the crimping pressure from the crimping portion 11 that abuts on the inner end surface thereof, and the coupler ring 43 and the coupler ring 43 are pressed by the crimping pressure acting from the crimping portion 11. The pair of

inner ring members

5 and 7 are securely fixed to the hub ring 4.

Then, a ring-shaped gear ring (slide gear) 26 in which the outer peripheral spline portion 43a of the coupler ring 43 meshes with the gear portion 44 of the outer joint member (not shown) is selectively meshed by sliding in the axial direction. The driving force is transmitted from the constant velocity universal joint to the wheel via the inner ring 7 and the hub wheel 4 in a state where the coupler ring 43 and the gear portion 44 of the outer joint member are connected via the gear ring 26. That is, at this time, the wheel supported by the hub wheel 4 is a driving wheel. In the state where the gear ring 26 is not engaged with the coupler ring 43, the driving force is not transmitted to the wheel, and at this time, the wheel supported by the hub wheel 4 becomes a driven wheel, and switching between four wheels and two wheels is selectively performed. Done.

In the present embodiment, the coupler ring 43 is formed of a steel material having a carbon content of medium carbon steel or less. Specifically, it is formed from a steel material containing 0.15 to 0.45 wt% carbon, preferably 0.38 to 0.43 wt% carbon. Then, the core is hardened in the range of 40 to 55 HRC (392 to 600 HV) by submerged quenching (quenching and tempering).

Thus, the amount of Cr in the coupler ring 43 is increased to approximately 0.09 to 0.12 wt% with respect to the hub ring 4 made of medium and high carbon steel such as S53C, and the tenacity is increased. In addition, when the carbon amount is high-carbon steel, the hardness becomes about HRC60 (700HV). However, in the present invention, the carbon content is hardened by sub-firing from a steel material having a medium carbon steel or less. A gear portion having an appropriate hardness can be obtained. That is, a hardness difference of approximately 132 to 340 HV can be made with respect to the surface hardness 260 HV of the crimped portion 11, and desired strength can be ensured as well as the outer peripheral spline portion 43 a and the inner peripheral spline portion 43 b. Therefore, in the caulking step, it is possible to prevent excessive stress from being generated in the coupler ring 43 and to cause deformation and micro cracks, and when the caulking portion 11 is formed, the small-diameter step portion 4b of the hub wheel 4 is formed. Can be plastically deformed outward in the radial direction, preventing a caulking defect such as a microcrack in the caulking portion 11 and preventing the bearing preload initially set over a long period of time. Can be maintained.

By adopting chromium molybdenum steel such as SCM440 or SCM430 to which Mo (molybdenum) is added approximately 0.15 to 0.3 wt% as the material of the coupler ring 43, brittleness can be suppressed. It is possible to reliably prevent the occurrence of micro cracks during the caulking process and to ensure the strength when a driving force is applied.

Moreover, in this embodiment, as shown to Fig.9 (a), the tooth bottom 43ab of the outer periphery spline part 43a may be formed in the single circular arc which consists of curvature radius R1, and also in (b) As shown, the tooth bottom 43ab ′ of the outer peripheral spline portion 43a ′ may be formed in a shape having two curvature radii R1. Thereby, the force at the time of caulking is disperse | distributed and the crack which generate | occur | produces in the tooth bottom 43ab, 43ab 'can be prevented. The compound R is carried out when a single R cannot cope with the R because no R is attached to the portion that contacts the other gear.

In this embodiment, the bearing preload is managed in the caulking process. The inner ring 7 and the coupler ring 43 are elastically deformed by the caulking process, and the bearing clearance is reduced by elastic deformation of these. Since there is a correlation between the elastic deformation amount and the clearance reduction amount, a regression equation is prepared in advance by conducting a test of the elastic deformation amount and the clearance reduction amount in a bearing having the same specifications.

Then, as shown in FIG. 10, the bearing clearance before caulking is measured, and the height W0 of the coupler ring 43 before caulking is measured. That is, the end portion of the small diameter step portion 4b of the hub wheel 4 'is formed in a cylindrical shape, and the inner spline portion 43b of the coupler ring 43 is in close contact with the large end surface 7e of the inner ring 7 in the hub spline portion 23. The height W0 of the coupler ring 43 is measured. After that, the height W1 of the coupler ring 43 after caulking is measured, and the amount of change in height (elastic deformation amount) ΔW = W0−W1 is calculated by calculating the clearance reduction amount using a regression equation confirmed in advance. Subtract this clearance reduction from the bearing clearance before tightening to finally calculate the bearing clearance after crimping.

∙ Bearing clearance after tightening due to preload is set to negative clearance, so it cannot be measured directly. In this way, the height of the coupler ring 43 before and after caulking can be measured to calculate the elastic deformation amount of the inner ring 7 and the coupler ring 43, and the preload amount can be indirectly managed from the elastic deformation amount. In the present invention, since the coupler ring 43 is difficult to be plastically deformed by caulking, the amount of elastic deformation can be measured with high accuracy, high accuracy, and stable preload management can be performed while suppressing variation.

The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

In the wheel bearing device according to the present invention, a coupler ring that selectively switches between four wheels and two wheels is fixed to an inner member having a hub wheel and an inner ring fitted to the hub wheel. It can be applied to a wheel bearing device having a third generation structure.

DESCRIPTION OF SYMBOLS 1 Inner member 2 Outer member 2a Outer rolling surface 2b Car body mounting flange 3 Rolling body 4, 4 'Hub wheel 4a Shoulder part 4b Small diameter step part 5, 7 Inner ring 5a Inner rolling surface 5b, 7b Large collar part 5c, 7c Small flange portion 5d, 7d Small end surface 6 Wheel mounting flange 6a Hub bolt 7e Large end surface 8 of inner ring Cage 9, 15 Annular groove 10, 16 Elastic ring 11 Clamping portion 12 Seal 13 Rotational speed sensor 13a Insertion portion 13b Non-insertion portion 14 Sensor insertion hole 17 Sensor mounting portion 18 Pulsar ring 18a Uneven portion 19, 20 Rolling bearing 21, 27, 30, 32, 34, 36, 43, 43 'Coupler ring 21a End surface 22, 26a, 28 on the inner side of the coupler ring 33, 35, 37, 43b Inner peripheral spline portions 22a, 23a, 24a, 28a, 33a, 35a, 37a Spline grooves 22b, 23b, 4b, 28b, 37b Spline ridge 23 Hub spline part 24, 43a, 43a 'Outer peripheral spline part 25 Axle side spline part 26 Gear ring 29 Tapered surface 31, 32a, 34a Chamfered part 38 Non-grooved part 43ab, 43ab' Peripheral spline part tooth Bottom 44 Gear portion 50 of outer joint member Wheel bearing device 51 Axle 52 Hub shaft 53 Double row tapered roller bearing 54 Coupler ring 55 Deep groove ball bearing 56 Needle roller bearing 57 Sleeve portion 58 Flange portion 58a Through hole 59 Bent portion 60 Spline portion 60a Spline groove 60b of hub shaft Spline protrusion 60c of hub shaft End point portion 61 of spline groove of hub shaft Inner circumferential side spline portion 61a Spline groove 61b Spline protrusion 62 Inner ring 63 Outer ring 63a First outer ring 63a Track part 63b No. of outer ring Track part 63c Flange part 64, 65 Tapered roller 66 First inner ring member 66a First race part 66b of inner ring End surface 67 of first inner ring member Second inner ring member 67a Second race part 67b of inner ring End face 68 of inner ring member of seal ring 69 Outer peripheral side spline part 69a Spline concave line 69b of coupler ring Spline convex part 70 of coupler ring Other side chamfered part 71 Side face 71a of coupler ring One end part A of the other side side chamfered part A Coupler ring Dimension B from the end face on the inner side to the edge of the spline ridge BO of the spline ridge BO of the hub spline part Fastening member C Bottom of the spline ridge of the hub spline part ΔD Hub spline part and coupler inner ring spline Diameter difference from the groove Da Groove diameter Db of the spline groove of the hub spline part Inner splice of the coupler ring Inner diameter h The height of the spline ridge of the hub spline section L The distance from the side surface of the coupler ring to one end of the chamfer of the other end side The radius of curvature R1 of the end surface of the spline ridge of the hub spline section R1 of the outer spline section Radius of curvature r of the root radius of curvature G of the chamfered portion of the coupler ring Gearing G1 Spline portion H0 Height of the spline ridge of the coupler ring H1 Radial dimension of the chamfered portion of the coupler ring T Starting point X of the tapered surface Side surface of the coupler ring Distance W0 to end point of hub shaft spline groove W0 Coupler height before caulking W1 Coupler height after caulking ΔW Height change

Claims

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A hub wheel integrally having a wheel mounting flange for mounting a wheel at one end and having a cylindrical small-diameter stepped portion extending in the axial direction on the outer periphery, and a small diameter stepped portion of the hub wheel via a predetermined squeezing An inner member formed of at least one inner ring press-fitted and formed with a double-row inner rolling surface facing the double-row outer rolling surface on the outer periphery;
A double row rolling element that is accommodated so as to roll freely between the rolling surfaces of the inner member and the outer member via a cage,
A coupler ring in which an inner peripheral spline portion and an outer peripheral spline portion are formed is fitted to the end portion of the small-diameter step portion of the hub wheel, and the end portion of the small-diameter step portion is formed by plastic deformation radially outward. In the wheel bearing device in which the inner ring is fixed in the axial direction via the coupler ring by a caulking portion,
The inner peripheral spline portion of the coupler ring includes a plurality of spline grooves and a plurality of spline protrusions alternately formed, and a plurality of splines formed alternately on the outer peripheral surface on the inner side of the small diameter step portion of the hub wheel. The hub spline part which consists of a concave line and a plurality of spline convex lines meshes with each other, and the end surface of the spline convex line of the hub spline part is formed by a single arc having a predetermined radius of curvature R. It is larger than the dimension A (R> A) from the end surface of the inner side of the coupler ring to the edge of the spline ridge, and larger than the height h of the spline ridge (R> h). A wheel bearing device characterized by being set.
When the groove diameter of the spline groove of the hub spline part is Da and the inner diameter of the spline protrusion of the inner peripheral spline in the coupler ring is Db, the inner diameter Db of the spline protrusion is the diameter of the spline groove of the hub spline part. The wheel bearing device according to claim 1, wherein the wheel bearing device is larger than the groove diameter Da and has a diameter difference ΔD = (Db-Da) of 1.0 mm or less.
A tapered surface is formed at the inner diameter of at least the inner end of the spline ridges at the inner peripheral spline portion of the coupler ring, and the starting point of the tapered surface is the edge of the spline ridge of the hub spline portion. And the bearing apparatus for wheels of Claim 1 or 2 arrange | positioned in the range with the bottom part of the said spline groove.
A tapered chamfered portion is formed at the inner diameter of at least the inner end of the both ends of the coupler ring, and the radial dimension H1 of the chamfered portion is the height H0 of the spline protrusion of the inner peripheral spline portion. 4. The wheel bearing device according to claim 1, wherein the wheel bearing device is set to be larger (H1 ≧ H0).
The wheel bearing device according to any one of claims 1 to 4, wherein a tapered chamfered portion is formed at least at an end on the inner side of both end portions of the spline recess in the inner peripheral spline portion of the coupler ring.
5. The arc-shaped chamfered portion having a predetermined radius of curvature is formed at least at the end on the inner side of both end portions of the spline recess in the inner peripheral spline portion of the coupler ring. Wheel bearing device.
The wheel bearing device according to any one of claims 1 to 4, wherein a spline groove in an inner peripheral spline portion of the coupler ring is stopped at an inner end portion to form a non-groove portion.
The coupler ring is made of a steel material having a carbon amount of medium carbon steel or less, and is hardened to the core by quenching, and the outer peripheral spline portion formed on the outer periphery and the inner peripheral spline portion are set to the same hardness. The wheel bearing device according to any one of claims 1 to 7.
The wheel bearing device according to claim 1, wherein the surface hardness of the coupler ring has a hardness difference of at least 130 HV from the hub wheel.
The wheel bearing device according to any one of claims 1 to 9, wherein the coupler ring is contained in 0.09 to 0.12 wt% of Cr, and the surface hardness is set in a range of 392 to 600 HV.
The wheel bearing device according to any one of claims 1 to 9, wherein the coupler ring is made of a steel material made of 0.15 to 0.45 wt% carbon.
10. The wheel bearing device according to claim 1, wherein the coupler ring is made of chromium steel containing 0.12 to 0.2 wt% of Cr, and is hardened by quenching and tempering.
The wheel bearing device according to claim 12, wherein the coupler ring is made of chromium molybdenum steel containing 0.15 to 0.3 wt% of Mo.
The wheel bearing device according to any one of claims 1 to 13, wherein a tooth bottom of an outer peripheral spline portion of the coupler ring is formed in an arc shape having a predetermined radius of curvature.
An outer joint member constituting a constant velocity universal joint is coupled to the inner member, and an axle side spline portion having the same diameter and the same shape as the outer peripheral spline portion of the coupler ring is formed on the outer peripheral surface of the outer joint member. In addition, the outer peripheral spline portion and the axle side spline portion are arranged coaxially with each other, and the inner side spline portion of the drive switching gear ring slidable in the axial direction is meshed with the axle side spline portion. Item 2. A wheel bearing device according to Item 1.
The hub wheel is made of medium and high carbon steel containing carbon of 0.40 to 0.80 wt%, and the surface hardness is 58 to 64 HRC by induction quenching from the inner side base of the wheel mounting flange to the small diameter step. 2. The wheel bearing device according to claim 1, wherein a predetermined hardened layer is formed in the range, and the caulking portion is an unquenched portion having the surface hardness after forging.
An outer member integrally having a vehicle body mounting flange for being attached to a knuckle constituting a suspension device on the outer periphery, and an outer rolling surface of a double row integrally formed on the inner periphery;
A hub wheel integrally having a wheel mounting flange for mounting a wheel at one end and having a cylindrical small-diameter stepped portion extending in the axial direction on the outer periphery, and a small diameter stepped portion of the hub wheel via a predetermined squeezing An inner member formed of at least one inner ring press-fitted and formed with a double-row inner rolling surface facing the double-row outer rolling surface on the outer periphery;
In the preload management method for a wheel bearing device comprising a double row rolling element that is rotatably accommodated between both rolling surfaces of the inner member and the outer member via a cage,
In a state where a predetermined bearing preload is applied to the inner ring through a ring-shaped coupler ring by a caulking portion formed by plastically deforming an end portion of the small-diameter step portion of the hub ring radially outward. Measure the bearing clearance before tightening,
The height from the reference surface of the coupler ring before and after caulking is measured, and the amount of change in the height is calculated by a regression equation in which the relationship between the amount of elastic deformation and the amount of clearance reduction is confirmed in advance. A preload management method for a wheel bearing device, wherein the bearing clearance after caulking is calculated by subtracting the clearance reduction amount from the bearing clearance before caulking.