JP2005344829A - Bearing device for driving wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a driving wheel superior in rotational run-out accuracy, and capable of securing a stable magnetic characteristic and detecting accuracy of a sensor while enhancing a degree of freedom of an installation space of a magnetic encoder and the sensor. <P>SOLUTION: This bearing device for the driving wheel has an outside member 4 for forming double rows of outside rollingly traveling surfaces 4a on the inner periphery, and an inside member 5 composed of a hub wheel 1 having integrally a wheel installing flange 7 in one end part and an outside joint member 14 internally fitted in this hub wheel; and is constituted so that double rows of inside rollingly traveling surfaces 1a and 14a are formed on the outer periphery of the hub wheel 1 and the outside joint member 14, and a hardened recess-projection part 12 is formed in an inner diameter of the hub wheel 1, and is integrally and plastically joined by biting in by diametrally expanding a fitting part 20b formed in a shaft part 20. The magnetic encoder 23 is arranged in a state of engaging with a part of a boot groove 22 formed on the outer periphery of the outside joint member 14. This magnetic encoder 23 is alternately magnetized by a magnetic pole in the peripheral direction by mixing magnetic substance powder in elastomer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a drive wheel bearing device provided with a rotational speed detecting device for rotatably supporting a wheel of an automobile or the like and detecting the rotational speed of the wheel.

  A bearing device for a drive wheel equipped with a rotational speed detector for detecting the rotational speed of the wheel by controlling the anti-lock brake system (ABS) while rotatably supporting the wheel of the automobile with respect to the suspension device. Is generally known. Conventionally, in such a drive wheel bearing device, a seal device is provided between an inner member and an outer member that are in rolling contact with each other through a rolling element, and a magnetic encoder in which magnetic poles are alternately arranged in a circumferential direction is provided as the seal. The rotation speed detection device is constituted by a magnetic encoder and a rotation speed sensor that is arranged to face the magnetic encoder and detects a magnetic pole change of the magnetic encoder accompanying the rotation of the wheel.

  The drive wheel bearing device shown in FIG. 7 is a typical example of this, and has a vehicle body mounting flange 51b integrally attached to the vehicle body (not shown) on the outer periphery, and a double row outer rolling surface on the inner periphery. The outer member 51 on which 51a and 51a are formed and the wheel mounting flange 53 to which a wheel (not shown) is attached at one end are integrally provided, and the wheel (see FIG. A hub bolt 54 for attaching the inner rolling surface 51a is mounted on the outer periphery of the hub bolt 54. The inner rolling surface 52a faces the double rolling outer rolling surface 51a and 51a, and extends axially from the inner rolling surface 52a. A hub wheel 52 formed with a cylindrical small-diameter stepped portion 52b and formed with serrations for torque transmission on the inner periphery, and an inner ring press-fitted into the small-diameter stepped portion 52b and formed with the other inner rolling surface 55a on the outer periphery. 55.

  A double-row rolling element (ball) 56 is accommodated by a cage 57 between the double-row outer rolling surfaces 51a and 51a and the inner rolling surfaces 52a and 55a facing these. Further, seals 59 and 60 are respectively attached to the annular spaces formed between the inner member 58 composed of the hub wheel 52 and the inner ring 55 and the outer member 51, and the lubricating grease sealed inside the bearing is provided. Leakage and rainwater and dust are prevented from entering the bearing from the outside.

  Of these seals 59, 60, the inboard-side seal 60 mounted between the outer member 51 and the inner ring 55 is internally fitted to the outer member 51 serving as a fixed-side raceway, as shown in FIG. It is externally fitted to a seal ring 63 composed of a cored bar 61 having an L-shaped cross-section, a seal member 62 vulcanized and bonded integrally to the cored bar 61, and an inner ring 55 serving as a rotating raceway. And a slinger 64 having an L-shaped cross section. The seal member 62 is made of an elastic member such as rubber, and includes three seal lips, that is, a side lip 62a, a grease lip 62b, and an intermediate lip 62c, and the end edge of the side lip 62a is the inner surface of the standing plate portion 64b of the slinger 64. The tip edges of the remaining grease lip 62b and intermediate lip 62c are in sliding contact with the cylindrical portion 64a of the slinger 64.

A magnetic encoder 65 mixed with magnetic powder is vulcanized and bonded integrally to the outer surface of the slinger 64. The magnetic encoder 65 is composed of a rubber magnet having magnetic poles N and S alternately formed in the circumferential direction, and constitutes a rotary encoder for detecting wheel rotation speed. The seal ring 63 and the tip of the standing plate portion 64b of the slinger 64 are opposed to each other through a slight radial clearance, and the labyrinth seal 66 is configured up to this clearance. With such a configuration, sufficient sealing performance can be exhibited even in an environment where a large amount of foreign matter such as rainwater and muddy water exists.
JP 2002-147478 A

  However, in such a conventional drive wheel bearing device, in order to ensure stable magnetic characteristics and detection accuracy of a sensor (not shown), the rotational deflection of the magnetic encoder 65 itself, the distance between the magnetic encoder 65 and the sensor, The so-called air gap must be strictly controlled. Therefore, it is necessary to directly attach the slinger 64 to which the magnetic encoder 65 is joined to a rotation-side member having good rotational runout accuracy, and there is a problem that the installation space of the sensor is restricted. In this conventional magnetic encoder 65, since the slinger 64 is attached to the outer diameter of the inner ring 55 on which the inner rolling surface 55a is directly formed, good rotational runout accuracy can be obtained, but the magnetic encoder 65 and the sensor are installed. The problem was that space was limited and design freedom was poor.

  The present invention has been made in view of such circumstances, and has a high rotational shake accuracy, a high degree of freedom in installation space for magnetic encoders and sensors, and a drive that can ensure stable magnetic characteristics and sensor detection accuracy. An object of the present invention is to provide a wheel bearing device.

  In order to achieve the object, the invention according to claim 1 of the present invention is a drive wheel bearing device in which a hub wheel, a double row rolling bearing, and a constant velocity universal joint are unitized, and the double row The rolling bearing has an outer member having a double row outer rolling surface formed on the inner periphery, a wheel mounting flange integrally formed at one end, and the outer surface facing the double row outer rolling surface on the outer periphery. An inner rolling surface, a hub wheel formed with a cylindrical small-diameter stepped portion extending in the axial direction from the inner rolling surface, and fitted into the hub wheel, and on the outer periphery of the double-row outer rolling surface. An inner member composed of the opposite inner rolling surface and an outer joint member of the constant velocity universal joint integrally formed with a shaft portion extending in the axial direction from the inner rolling surface, and the inner member A double row rolling element housed between the rolling surfaces of the outer member so as to freely roll, and the shaft portion is plastically deformed. In the drive wheel bearing device in which the hub wheel and the outer joint member are integrally plastically coupled by caulking to the hub wheel, a ring-shaped magnetic encoder is disposed on the outer periphery of the outer joint member. The magnetic encoder employs a configuration in which magnetic powder is mixed into the elastomer and magnetic poles are alternately magnetized in the circumferential direction.

  Thus, in the drive wheel bearing device in which the hub wheel and the outer joint member are integrally plastically coupled, a ring-shaped magnetic encoder is disposed on the outer periphery of the outer joint member, and this magnetic encoder is attached to the elastomer. Magnetic powder is mixed and the magnetic poles are alternately magnetized in the circumferential direction, so the rotational shake accuracy is good and the installation space for the magnetic encoder and sensor is high. The air gap can be set with high accuracy without strictly restricting the positioning accuracy in the direction. Therefore, it is possible to provide a drive wheel bearing device capable of ensuring stable magnetic characteristics and sensor detection accuracy.

  Preferably, as in the invention described in claim 2, a hardened uneven portion is formed on the inner diameter of the hub wheel, and the fitting portion formed in the shaft portion is expanded in diameter so that the uneven portion is bitten. Therefore, if the hub wheel and the outer joint member are integrally plastically coupled, it is not necessary to manage the preload by tightening firmly with a nut or the like, and it is possible to reduce the weight and size, and to reduce the hub wheel. It is possible to improve the strength and durability and maintain the preload amount for a long time.

  According to a third aspect of the present invention, the magnetic encoder is disposed in a state of engaging with a part of a boot groove formed on an outer periphery of the outer joint member, and the boot is inserted through the magnetic encoder. Since the outer joint member is tightened, a minute fitting clearance of the boot mounting portion can be closed with this magnetic encoder, and the sealing performance is improved.

  In the invention according to claim 4, since the magnetic encoder is protected by a sensor cover fixed to the outer member, muddy water, stepping stones and the like do not directly contact the magnetic encoder or sensor. In addition to improving the durability of the rotational speed detection device, it is possible to ensure stable magnetic characteristics and sensor detection accuracy.

  Preferably, as in the invention described in claim 5, since the sensor cover is formed by pressing a stainless steel plate or a cold-rolled steel plate subjected to rust prevention, a knuckle constituting a suspension device Even if it is made of a light alloy such as an aluminum alloy, galvanic corrosion can be prevented. Therefore, in order to prevent the galvanic corrosion, the plating process that has been often applied to the outer member can be eliminated, and the durability of the apparatus can be improved and the cost can be reduced.

  According to a sixth aspect of the present invention, the magnetic encoder is provided between the rolling elements of the double row, and a sensor facing the magnetic encoder via a predetermined radial clearance is a radial direction of the outer member. Therefore, the rotational speed detecting device can be reliably protected from muddy water, stepping stones and the like.

  A bearing device for a driving wheel according to the present invention is a bearing device for a driving wheel in which a hub wheel, a double row rolling bearing, and a constant velocity universal joint are unitized, and the double row rolling bearing is provided on an inner periphery. An outer member formed with a double row outer rolling surface, a wheel mounting flange integrally formed at one end, and one inner rolling surface facing the double row outer rolling surface on the outer periphery, A hub wheel formed with a cylindrical small-diameter stepped portion extending in the axial direction from the inner rolling surface, and the other inner rolling surface that is fitted in the hub wheel and faces the outer surface of the double row on the outer periphery. An inner member composed of an outer joint member of the constant velocity universal joint integrally formed with a shaft portion extending in the axial direction from the inner rolling surface, and both rolling of the inner member and the outer member. A double row rolling element housed between the faces so as to roll freely, and plastically deforming the shaft portion and crimping the hub ring And the hub wheel and the outer joint member are integrally plastically coupled, a ring-shaped magnetic encoder is disposed on the outer periphery of the outer joint member, and magnetic powder is mixed in the elastomer, Since the magnetic poles are alternately magnetized in the circumferential direction, the rotational deflection accuracy is good, the degree of freedom of installation space for the magnetic encoder and sensor is high, and the positioning accuracy in the axial direction of the magnetic encoder and sensor is strictly regulated. Even without this, the air gap can be set with high accuracy. Therefore, it is possible to provide a drive wheel bearing device capable of ensuring stable magnetic characteristics and sensor detection accuracy.

  A bearing device for a driving wheel in which a hub wheel, a double row rolling bearing, and a constant velocity universal joint are unitized, and the double row rolling bearing has a double row outer rolling surface formed on an inner periphery. An outer member, a wheel mounting flange integrally formed at one end, one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and a cylindrical shape extending in the axial direction from the inner rolling surface A hub wheel formed with a small-diameter step portion, the other inner rolling surface that is fitted in the hub ring and faces the outer rolling surface of the double row on the outer periphery, and axially extends from the inner rolling surface. An inner member composed of an outer joint member of the constant velocity universal joint with an extending shaft portion formed integrally therewith, and a plurality of rolls accommodated between both rolling surfaces of the inner member and the outer member. A rolling irregularity portion formed on the inner diameter of the hub wheel, and the fitting portion formed on the shaft portion having a larger diameter. In the bearing device for a drive wheel in which the hub wheel and the outer joint member are integrally plastically coupled by biting into the uneven portion, the engagement portion is engaged with a part of the boot groove formed on the outer periphery of the outer joint member. A magnetic encoder is disposed in the combined state, and in this magnetic encoder, magnetic powder is mixed in the elastomer, and magnetic poles are alternately magnetized in the circumferential direction.

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 bearing device for a drive wheel according to the present invention, and FIG. 2 is an enlarged view of a main part of FIG. In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outboard side (left side in the drawing), and the side closer to the center is referred to as the inboard side (right side in the drawing).

  In this drive wheel bearing device, a hub wheel 1, a double row rolling bearing 2 and a constant velocity universal joint 3 are configured as a unit. The double-row rolling bearing 2 includes an outer member 4, an inner member 5, and double-row rolling elements (balls) 6 and 6. The outer member 4 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and integrally has a vehicle body mounting flange 4b for mounting to a vehicle body (not shown) on the outer periphery. Double row outer raceway surfaces 4a and 4a are formed on each other, and a hardened layer is formed in a surface hardness range of 58 to 64 HRC by induction hardening.

  On the other hand, the inner member 5 includes a hub wheel 1 and an outer joint member 14 which is fitted into the hub wheel 1 and will be described later. The hub wheel 1 is made of medium carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, and has a wheel mounting flange 7 for mounting a wheel to an end portion on the outboard side. A plurality of hub bolts 8 are planted at equal intervals in the circumferential direction. Further, on the outer periphery of the hub wheel 1, one inner rolling surface 1a facing the double row outer rolling surfaces 4a, 4a and a cylindrical small-diameter step portion extending in the axial direction from the inner rolling surface 1a. 1b is formed. Then, a hardened layer is formed with a surface hardness of 58 to 64 HRC by induction hardening over the inner rolling surface 1a and the small-diameter step portion 1b from the seal land portion in which the seal 10 on the outboard side described later is in sliding contact. Yes. As a result, the seal land which is the base of the wheel mounting flange 7 not only has improved wear resistance, but also has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 7. The durability of 1 is further improved.

  The constant velocity universal joint 3 includes an outer joint member 14, a joint inner ring 15, a cage 16, and a torque transmission ball 17. The outer joint member 14 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and has a cup-shaped mouth portion 18, a shoulder portion 19 that forms the bottom portion of the mouth portion 18, and the shoulder portion 19. A cylindrical shaft portion 20 extending in the axial direction from is integrally formed. The shaft portion 20 is formed with an in-row portion 20a that is cylindrically fitted to the small-diameter step portion 1b of the hub wheel 1 through a predetermined radial clearance, and a fitting portion 20b is formed at the end of the in-row portion 20a. .

  A curved track groove 18 a extending in the axial direction is formed on the inner periphery of the mouse portion 18, and a track groove 15 a corresponding to the track groove 18 a is formed on the outer periphery of the joint inner ring 15. In addition, on the outer periphery of the shoulder portion 19, the other inner rolling surface 14 a facing the double row outer rolling surfaces 4 a, 4 a is formed. Then, a hardened layer is formed with a surface hardness of 58 to 64 HRC by induction quenching from the seal land where the track groove 18a and the seal 11 on the inboard side are in sliding contact to the inner rolling surface 14a and the shaft portion 20. Has been. Here, the fitting part 20b is left raw after forging.

  Double row rolling elements 6 and 6 are accommodated between the double row outer raceway surfaces 4a and 4a of the outer member 4 and the double row inner raceway surfaces 1a and 14a opposed to these, and the cage 9, 9 is held by a roller 9. Further, seals 10 and 11 are attached to the end portion of the outer member 4 to prevent leakage of the lubricating grease sealed inside the bearing and intrusion of rainwater, dust and the like into the bearing from the outside. Here, a double-row angular contact ball bearing using balls as the rolling elements 6 is illustrated as the double-row rolling bearing 2. However, the present invention is not limited to this, and for example, a double-row tapered roller bearing using a tapered roller is used. There may be.

  Here, the concavo-convex portion 12 is formed on the inner periphery of the hub wheel 1, and a hardened layer is formed with a surface hardness in the range of 54 to 64 HRC by heat treatment. As the heat treatment, local heating is preferable, and quenching by high-frequency induction heating that can set the hardened layer depth relatively easily is preferable. The concave and convex portion 12 is formed in the shape of an iris knurl, and is a cross groove formed by a plurality of annular grooves formed independently by turning or the like and a plurality of axial grooves formed by broaching or the like substantially orthogonal to each other. Alternatively, it consists of a cross groove composed of spiral grooves inclined with respect to each other. Further, in order to ensure good biting property, the tip of the concavo-convex portion 12 has a spire shape such as a triangular shape.

  The end surface of the small-diameter step portion 1b of the hub wheel 1 is abutted with the shoulder portion 19 of the outer joint member 14, and the shaft portion 20 is fitted into the hub wheel 1 until it comes into a butted state. Then, a diameter expanding jig such as a mandrel is pushed into the inner diameter of the fitting portion 20b in the shaft portion 20 to increase the diameter of the fitting portion 20b, and the fitting portion 20b is bitten into the uneven portion 12 of the hub wheel 1. Caulking, the hub wheel 1 and the outer joint member 14 are integrally plastically coupled. As a result, it is not necessary to control the preload by tightening firmly with a nut or the like as in the prior art, so that the weight and size can be reduced and the strength and durability of the hub wheel 1 can be improved and long. The amount of preload can be maintained for a period. An end cap 13 is attached to the hollow shaft portion 20 to prevent the grease sealed in the mouth portion 18 from leaking to the outside. Although not shown, an end cap is also attached to the opening end of the hub wheel 1 to prevent rainwater or the like from entering the plastic coupling portion and rusting the portion.

  In addition to the configuration exemplified as means for plastically coupling the hub wheel 1 and the outer joint member 14, for example, although not shown, the shaft portion of the outer joint member is fitted into the hub wheel, and the shaft portion The ends may be plastically deformed radially outward to form a crimped portion, and both members may be fixed in the axial direction by the crimped portion.

  As shown in an enlarged view in FIG. 2, an annular boot groove 22 for fixing the boot 21 to the outer joint member 14 is formed at the opening end of the mouth portion 18. A ring-shaped magnetic encoder 23 is provided so as to engage with a part of the boot groove 22. In the magnetic encoder 23, magnetic powder such as ferrite is mixed in an elastomer such as rubber, and magnetic poles N and S are alternately magnetized in the circumferential direction. The magnetic encoder 23 may be vulcanized and bonded to a metal core (not shown) formed in a ring shape, and the metal core 23 may be fitted to the outer periphery of the mouse part 18. The outer periphery may be integrally joined by direct vulcanization adhesion or the like.

  The boot 21 has a large-diameter end 21a attached to the boot groove 22 via the magnetic encoder 23, and a boot band 21b is fastened to the outer periphery and fixed to the outer joint member 14. A minute fitting clearance of the portion can be closed by the magnetic encoder 23, and the sealing performance of the boot mounting portion is improved.

  In the present embodiment, since the magnetic encoder 23 is provided on the outer periphery of the mouse portion 18 in the outer joint member 14 in which the inner rolling surface 14a is directly formed, the rotational shake accuracy is good and the magnetic encoder 23 and the sensor are provided. The degree of freedom of installation space is high. Further, by adopting a radial type instead of the conventional axial type for the magnetic encoder 23, the air gap can be set with high accuracy without strictly restricting the positioning accuracy of the magnetic encoder 23 and the sensor in the axial direction. . Therefore, it is possible to provide a drive wheel bearing device capable of ensuring stable magnetic characteristics and sensor detection accuracy.

  FIG. 3 is a longitudinal sectional view showing a second embodiment of the bearing device for a drive wheel according to the present invention, and FIG. 4 is an enlarged view of a main part of FIG. Note that this embodiment basically differs from the above-described embodiment only in the installation position of the magnetic encoder, and other parts that are the same, the same parts, or the same function are given the same reference numerals and redundant descriptions. Omitted.

  In the present embodiment, a magnetic encoder 23 is provided on the outer periphery of the shoulder portion 19 of the outer joint member 14. A sensor 24 is disposed opposite to the magnetic encoder 23 via a predetermined radial clearance (air gap). The sensor 24 is fixed to a knuckle that constitutes a suspension device (not shown), and is protected by a sensor cover 25 so that muddy water, stepping stones, and the like do not directly contact the sensor 24. The sensor cover 25 has a substantially L-shaped cross section by pressing an austenitic stainless steel plate (JIS standard SUS304, etc.) or a rust-proof cold rolled steel plate (JIS standard SPCC, etc.). Further, it is formed in an annular shape as a whole and is fixed to the outer member 4.

  Recently, with the aim of reducing the weight of a vehicle, aluminum alloys are increasingly used for the knuckle that constitutes the suspension system. However, the two kinds of metals are in contact with the outer member 4 and the knuckle. When exposed to a corrosive environment, a metal having a lower potential difference (in this case, an aluminum alloy knuckle) becomes an anode (anode), causing a problem of early corrosion. Corrosion due to such a combination of different metals, so-called galvanic corrosion, can cause galvanic corrosion at an early stage and may significantly reduce durability. However, the outer member 4 is attached to the knuckle via the sensor cover 25 described above. Therefore, such galvanic corrosion can be prevented. Therefore, in order to prevent the galvanic corrosion, the plating process that has been often applied to the outer member can be eliminated, and the durability of the apparatus can be improved and the cost can be reduced.

  FIG. 5 is a longitudinal sectional view showing a third embodiment of the bearing device for a drive wheel according to the present invention, and FIG. 6 is an enlarged view of a main part of FIG. Note that this embodiment basically differs from the above-described embodiment only in the installation position of the magnetic encoder, and other parts that are the same, the same parts, or the same function are given the same reference numerals and redundant descriptions. Omitted.

  In this embodiment, the magnetic encoder 23 is provided on the outer periphery of the shaft portion 20 of the outer joint member 14 and between the double row rolling elements 6 and 6 constituting the double row rolling bearing 2 ′. A sensor 26 is disposed opposite to the magnetic encoder 23 via a predetermined radial clearance (air gap). The sensor 26 is fitted into a mounting hole 28 that penetrates the outer member 27 in the radial direction, and is fixed via a fixing screw (not shown). Thus, since the rotational speed detection device 29 constituted by the magnetic encoder 23 and the sensor 26 is built in the double row rolling bearing 2 ', the rotational speed detection device 29 is surely protected from muddy water, stepping stones and the like. be able to.

  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.

  The drive wheel bearing device according to the present invention can be applied to a drive wheel bearing device having a structure in which a hub wheel, a double row rolling bearing, and a constant velocity universal joint are unitized.

It is a longitudinal section showing a 1st embodiment of a bearing device for drive wheels concerning the present invention. It is a principal part enlarged view same as the above. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the bearing apparatus for drive wheels which concerns on this invention. It is a principal part enlarged view same as the above. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the bearing apparatus for drive wheels which concerns on this invention. It is a principal part enlarged view same as the above. It is a longitudinal cross-sectional view which shows the conventional bearing apparatus for drive wheels. It is a principal part enlarged view same as the above.

Explanation of symbols

1 ...... Hub wheel 1a, 14a ..... Inner rolling surface 1b ..... Small diameter step portion 2, 2 '.. ············· Double row rolling bearing 3 ······························································ ··· Outer rolling surface 4b ········ Body mounting flange 5 ···················· Inner member 6・ ・ ・ ・ Rolling element 7 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 8 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub bolt 9 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Holding Vessel 10, 11 ... Seal 12 ... Uneven part 13 ... End cap 14 ... ... Outer joint member 15 ... Fitting inner ring 15a, 18a ... ..Track groove 16 ... Cage 17 ... Torque transmission ball 18 ... Mouse part 19 ... ... Shoulder 20 ... Shaft 20a ... In-row 20b ... Fitting Part 21 ... Boot 21a ... Large diameter end 21b ... Boot band 22 ... ... Boot groove 23 ... Magnetic encoder 24, 26 ... Sensor 25 ... Sensor cover 28 ...・ ・ ・ ・ ・ ・ ・ ・ Mounting hole 29 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rotational speed detection device 51 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer member 51a ・ ・ ・ ・ ・ ・ ・ ・..Outer rolling surface 51b ··· Body mounting flange 52 ··········· Hub wheels 52a, 55a ··· Inner rolling surface 52b ··· Small diameter step 53 ..... Wheel mounting flange 54 ..... Hub bolt 55 ..... Inner ring 56 ........... Moving body 57 ... Retainer 58 ... Inner member 59 ... Outboard side seal 60 ... ·················· Seal 61 on the inboard side ················································· ... Side lip 62b ... Grease lip 62c ... Intermediate lip 63 ... Seal ring 64 ...・ ・ ・ ・ ・ ・Slinger 64a ... Cylindrical part 64b ... Vertical plate part 65 ... Magnetic encoder 66 ... .... Labyrinth seal

Claims (6)

A drive wheel bearing device in which a hub wheel, a double row rolling bearing, and a constant velocity universal joint are unitized,
The double row rolling bearing is an outer member in which a double row outer rolling surface is formed on the inner periphery,
A wheel mounting flange is integrally formed at one end, one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and a cylindrical small diameter step portion extending in the axial direction from the inner rolling surface. The formed hub wheel, the other inner rolling surface that is fitted in the hub wheel and faces the outer rolling surface of the double row, and the shaft portion that extends in the axial direction from the inner rolling surface are integrated. An inner member composed of an outer joint member of the constant velocity universal joint formed on
The inner member and a double row rolling element accommodated in a freely rolling manner between both rolling surfaces of the outer member, and the shaft portion is plastically deformed to be swaged to the hub ring. In the drive wheel bearing device in which the hub wheel and the outer joint member are integrally plastically coupled,
A ring-shaped magnetic encoder is disposed on the outer periphery of the outer joint member, and the magnetic encoder is characterized in that magnetic powder is mixed in an elastomer and magnetic poles are alternately magnetized in the circumferential direction. Drive wheel bearing device.   A hardened uneven portion is formed on the inner diameter of the hub wheel, and the hub wheel and the outer joint member are integrally plasticized by enlarging the fitting portion formed on the shaft portion and biting into the uneven portion. The drive wheel bearing device according to claim 1, wherein the drive wheel bearing device is coupled.   The magnetic encoder is disposed in a state of engaging with a part of a boot groove formed on an outer periphery of the outer joint member, and the boot is fastened to the outer joint member via the magnetic encoder. Or the bearing apparatus for driving wheels of 2.   The drive wheel bearing device according to claim 1, wherein the magnetic encoder is protected by a sensor cover fixed to the outer member.   The drive wheel bearing device according to claim 4, wherein the sensor cover is formed by pressing a stainless steel plate or a cold-rolled steel plate subjected to rust prevention.   The magnetic encoder is provided between the double-row rolling elements, and a sensor facing the magnetic encoder via a predetermined radial clearance is provided in a mounting hole formed by penetrating in the radial direction of the outer member. The drive wheel bearing device according to claim 1 or 2, wherein the drive wheel bearing device is fitted.

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