JP2008267583A - Bearing device for wheel with rotation speed detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a wheel with a rotation speed detector improved in reliability by securing magnetic flux input to a magnetic sensor, and improving airtightness. <P>SOLUTION: A core 24 of a seal plate 21 is formed of a cold-rolled steel plate subjected to a rustproof treatment; a window 31 opened radially outward is formed in a region of its cylindrical part 24a for arranging a rotating speed sensor 29 therein; a resin material of a sensor holder 20 is filled in the window 31 by turning around it; a detection surface of the rotating speed sensor 29 is arranged to be flush with an outer-diameter side opening end of the window 31; the window 31 is formed to expose all the position at which a sensor element surface 32 of the rotating speed sensor 29 is located; the circumferential width of the window 31 is formed not larger than twice as much as the width of a magnetic pole of a magnetic encoder 28; the axial width of the window 31 is set not larger than 2/3 of that of the cylindrical part 24a of the core 24; and the edge width (d) from an inner edge of the window 31 to an edge of the cylindrical part 24a of the core 24 is set not larger than 1 mm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wheel bearing device with a rotation speed detection device that includes a rotation speed sensor that detects the rotation speed of a wheel of an automobile or the like.

  A wheel bearing with a rotation speed detecting device in which a wheel of an automobile is rotatably supported with respect to a suspension device and a device for detecting the rotation speed of the wheel for controlling an anti-lock brake system (ABS) is incorporated in the bearing. Devices are generally known. Conventionally, in such a wheel bearing device, a sealing device is provided between an inner member and an outer member that are in rolling contact with a rolling element, and a magnetic encoder in which magnetic poles are alternately arranged in a circumferential direction is provided as the sealing device. In addition, the rotational speed detecting device is constituted by a magnetic encoder and a rotational speed sensor that is arranged facing the magnetic encoder and detects a magnetic pole change of the magnetic encoder accompanying the rotation of the wheel.

  In general, the rotational speed sensor is attached to the knuckle after the wheel bearing device is attached to the knuckle constituting the suspension device. However, in order to eliminate the complexity of the air gap adjustment work between the rotation speed sensor and the magnetic encoder and to achieve further compactness, recently, a bearing apparatus for a wheel with a rotation speed detection device in which the rotation speed sensor is also incorporated in the bearing. Has been proposed.

  A structure as shown in FIG. 5 is known as an example of such a wheel bearing device with a rotational speed detection device. In this wheel bearing device with a rotational speed detection device, a hub wheel 55 and a double row rolling bearing 50 are unitized, and the double row rolling bearing 50 and a constant velocity universal joint 61 are detachably coupled. The double row rolling bearing 50 includes an outer member 51, an inner member 52, and double rows of balls 53 and 53. The outer member 51 integrally has a vehicle body mounting flange 51b to be attached to the knuckle 54 constituting the suspension device on the outer periphery, and double row outer rolling surfaces 51a and 51a are integrally formed on the inner periphery. .

  On the other hand, the inner member 52 includes a hub ring 55 and an inner ring 56 fixed to the hub ring 55. The hub wheel 55 integrally has a wheel mounting flange 55d for mounting a wheel (not shown) at one end portion, and an inner rolling surface facing one of the double-row outer rolling surfaces 51a, 51a on the outer periphery. 55a and a cylindrical small-diameter step 55b extending in the axial direction from the inner rolling surface 55a are formed, and a serration 55c for torque transmission is formed on the inner periphery.

  The inner ring 56 is formed with an inner rolling surface 56a opposite to the other of the double row outer rolling surfaces 51a, 51a on the outer periphery, and is press-fitted into the small-diameter step portion 55b of the hub wheel 55 through a predetermined shimiro. . And the inner ring | wheel 56 is fixed to the axial direction by the crimping part 57 formed by carrying out the plastic deformation of the edge part of the small diameter step part 55b to radial direction outward.

  Double-row balls 53 and 53 are disposed between the double-row outer raceway surfaces 51 a and 51 a of the outer member 51, and the inner raceway surface 55 a of the hub wheel 55 and the inner raceway surface 56 a of the inner ring 56. It is accommodated and is held by the cages 58 and 58 so as to be freely rollable. Further, seals 59 and 60 are attached to the opening portion of the annular space formed between the outer member 51 and the inner member 52, and leakage of the lubricating grease sealed inside the bearing and the inside of the bearing from the outside. Prevents intrusion of rainwater and dust.

  The constant velocity universal joint 61 includes an outer joint member 62, a joint inner ring 63, a cage 64 and a torque transmission ball 65. The outer joint member 65 integrally includes a cup-shaped mouth portion 66, a shoulder portion 67 that forms the bottom portion of the mouth portion 66, and a shaft portion 68 that extends from the shoulder portion 67 in the axial direction. A serration 68a that engages with the serration 55c of the hub wheel 55 is formed on the outer periphery of the shaft portion 68, and a male screw 68b is formed at the end of the serration 68a. Then, the outer joint member 62 is fitted into the hub wheel 55 through the serrations 55c and 68a so that torque can be transmitted, and the hub wheel 55 and the outer joint member 62 are detachable by a fixing nut 69 fastened to the male screw 68b. It has become.

  As shown in FIG. 6, the seal 60 is a so-called pack seal in which a first seal ring 70 and a second seal ring 71 are combined. The first seal ring 70 includes a cylindrical portion 72a that is insert-molded in a connector 81, which will be described later, and an inner diameter portion 72b that extends in a radial direction from the cylindrical portion 72a, and a core bar having a substantially L-shaped cross section. 72 and a seal member 73 which is attached to the inner diameter portion 72b of the cored bar 72 and is composed of a main lip 73a and an auxiliary lip 73b.

  The second seal ring 71 is attached to the inner ring 56 and includes a slinger 74 having a substantially L-shaped cross section, and a radial lip 75 attached to the slinger 74. A pulsar ring 76 is attached to the second seal ring 71. The pulsar ring 76 includes a core metal 77 that is fitted on the slinger 74 and has a substantially U-shaped cross section, and a multipolar magnet rotor 78 that is attached to the core metal 77. This multipolar magnet rotor 78 is magnetized from the radial direction so that rubber or resin containing magnetic powder is vulcanized and bonded and the N poles and S poles are alternately arranged in the circumferential direction.

  Here, a sensor holder 79 is laminated on the entire outer peripheral surface of the cored bar 72 in the first seal ring 70. The sensor holder 79 is formed of a nonmagnetic resin material such as polyphenylene sulfide (PPS), and a magnetic sensor 80 is embedded therein. A female connector 81 that connects the magnetic sensor 80 and a harness (not shown) connected to the electronic circuit of the vehicle body protrudes radially outward at a predetermined circumferential position of the sensor holder 79. It is integrally formed.

  As described above, since the radial lip 75 is disposed outside the pulsar ring 76, the pulsar ring 76 can be prevented from being contaminated by dust or the like, and the main lip 73a and the auxiliary lip 73b of the first seal ring 70 can be prevented. Therefore, it is possible to prevent metal wear powder or the like generated by the rotation of the ball 53 from adhering to the pulsar ring 76, and to prevent a decrease in detection accuracy.

  Further, in the cylindrical portion 72a of the cored bar 72 constituting the first seal ring 70, a window 82 that opens radially outward is provided in a region where the magnetic sensor 80 is disposed, as shown in FIG. ing. The window 82 has a size and shape larger than the outer shape of the magnetic sensor 80 as viewed from the radial direction, or substantially the same size and shape as the outer shape of the magnetic sensor 80. The window 82 is filled with a resin outer package 83. . The magnetic sensor 80 is disposed so that its detection surface is flush with the outer diameter side opening end of the window 82 (see FIG. 6).

By providing such a window 82, no metal material is interposed between the opposing surfaces of the magnetic sensor 80 and the pulsar ring 76, and therefore, as shown in FIG. 72 without passing through the window 82 and without causing a phenomenon that the detection operation of the magnetic sensor 80 is lowered due to the eddy current generated when the magnetic field lines pass through the cored bar 72. That's it. Further, in addition to this, the facing distance between the magnetic sensor 80 and the pulsar ring 76 can be reduced, so that the detection accuracy of the magnetic sensor 80 can be increased.
JP 2005-98333 A

  In such a conventional wheel bearing device with a rotational speed detecting device, the cored bar 72 is a nonmagnetic material made of nonmagnetic stainless steel (JIS standard SUS304 or the like) so that the magnetic sensor 80 is attached, that is, so as not to be magnetically shielded. It is formed with. However, since this kind of non-magnetic material is expensive, a reasonable magnetic material such as a cold rolled steel plate (JIS standard SPCC) having a low material cost and good workability is used as the material of the core metal 72. Although it is advantageous, when a magnetic material is used for the metal core 72, if the size of the window 82 is too small, the magnetic flux between the multipolar magnet rotor 78 and the magnetic sensor 80 is reduced, leading to a decrease in function. On the other hand, when the size of the window 82 is too large, the strength of the cored bar 72 is lowered, and the adhesion between the cored bar 72 and the resin mold of the connector 81 is reduced, which leads to a decrease in airtightness and reliability. There was a problem.

  The present invention has been made in view of such circumstances, and provides a wheel bearing device with a rotational speed detection device that secures a magnetic flux input to a magnetic sensor and improves airtightness to improve reliability. The purpose is to do.

  In order to achieve the object, the invention according to claim 1 of the present invention has a vehicle body mounting flange integrally attached to the suspension on the outer periphery, and a double row outer rolling surface is integrally formed on the inner periphery. A hub wheel having a wheel mounting flange for mounting a wheel at one end and a small-diameter step portion extending in the axial direction on the outer periphery, and press-fitting into the small-diameter step portion of the hub ring An inner member formed of at least one inner ring formed on the outer periphery and formed with a double-row inner rolling surface opposite to the double-row outer rolling surface, and both rolling of the inner member and the outer member. A double row rolling element housed between the running surfaces so as to be freely rollable, a seal attached to an opening of an annular space formed between the outer member and the inner member, and the outer member Mounted on the inner side end, non-magnetic synthetic resin is formed by injection molding and rotated A sensor holder in which a degree sensor is embedded, and an inner seal of the seals is arranged opposite to each other, and an annular seal plate having a substantially L-shaped cross section, and an outer ring of the inner ring A pulsar ring having a magnetic encoder that is attached to a diameter and includes a slinger having a substantially L-shaped cross-section formed by pressing a steel plate and magnetized with magnetic poles N and S alternately at equal intervals in the circumferential direction. The seal plate is composed of a cylindrical portion that is insert-molded in the sensor holder and an inner diameter portion that extends radially from the cylindrical portion, and the steel plate is formed into a substantially L-shaped cross section by pressing. In the wheel bearing device with a rotational speed detecting device comprising the cored bar and a seal member integrally joined to the inner diameter part of the cored bar, the rotational speed sensor of the cylindrical part of the cored bar is arranged. A window that opens radially outward is provided in a region where the resin material of the sensor holder wraps around and is filled in the window, and the detection surface of the rotation speed sensor is connected to the outer diameter side opening end of the window. The window is formed so that all the positions of the sensor element surface of the rotational speed sensor are exposed, and the circumferential width of the window is equivalent to two magnetic poles of the magnetic encoder. The width in the axial direction of the window is less than or equal to two thirds of the axial width of the cylindrical portion of the core metal, and the width from the inner edge of the window to the edge of the cylindrical portion of the core metal is 1 mm. It is set to be above.

  In this way, in the wheel bearing device with a rotation speed detection device of the inner ring rotation type, a window that opens radially outward is provided in a region where the rotation speed sensor of the cylindrical portion of the core metal is disposed, and the window is within this window. The resin material of the sensor holder wraps around and is disposed so that the detection surface of the rotational speed sensor is flush with the opening end of the outer diameter side of the window, and the window is the sensor element surface of the rotational speed sensor. It is formed so that all the positions are exposed, and the circumferential width of the window is formed to be equal to or less than the width of the two magnetic poles of the magnetic encoder, and the axial width of the window is two thirds of the axial width of the cylindrical portion of the cored bar. In the following, since the width from the inner edge of the window to the end edge of the cylindrical portion of the core metal is set to 1 mm or more, no metal material is interposed between the opposed surfaces of the rotational speed sensor and the magnetic encoder. , Suppresses the generation of eddy currents during rotation. The magnetic lines of force generated from the magnetic encoder pass through the cored bar window, the distance between the rotational speed sensor and the magnetic encoder can be reduced, and the magnetic flux between the magnetic encoder and the rotational speed sensor can be ensured. Adhesion between the gold and the resin mold of the sensor holder can be ensured, and the detection accuracy of the rotation speed sensor can be improved and the reliability can be improved.

  Preferably, if the cored bar is formed of a rust-proof cold rolled steel plate as in the invention described in claim 2, the material price is low, the workability is good, and the cost is reduced. be able to.

  According to a third aspect of the present invention, a connector for connecting the rotational speed sensor and a harness connected to the electronic circuit at a predetermined circumferential position of the sensor holder is inclined radially outward by a predetermined angle. If a recess is formed in the connector and the recess is fitted via a predetermined shimiro so as to cover the inner end of the outer member, the harness is connected. When this is done, the pressure input is not directly applied to the connector, and this pressure input is received at the end of the outer member, so that an excessive force acts on the connector and the position accuracy of the seal and the rotation speed sensor is not destroyed. Therefore, the reliability and assembly can be improved.

  According to a fourth aspect of the present invention, the pulsar ring includes a metal core that is press-fitted into the cylindrical portion of the slinger and is formed into a substantially U-shaped cross-section by pressing from a magnetic steel plate. If the magnetic encoder is integrally joined to the outer diameter portion of the metal core, the seal can be made compact and the sealing performance can be improved.

  Further, as in the fifth aspect of the present invention, if the seal member integrally has a plurality of seal lips, and these seal lips are in sliding contact with the core metal of the pulsar ring, the pulsar ring is contaminated by dust or the like. Can be prevented, and a decrease in detection accuracy can be avoided.

  The wheel bearing device with a rotational speed detection device according to the present invention has a vehicle body mounting flange integrally attached to the suspension on the outer periphery, and an outer side in which a double row outer rolling surface is integrally formed on the inner periphery. And a hub wheel integrally having a wheel mounting flange for mounting a wheel at one end thereof and having a small-diameter step portion extending in the axial direction on the outer periphery, and at least one press-fitted into the small-diameter step portion of the hub ring An inner member formed of two inner rings and having an outer periphery formed with a double-row inner rolling surface opposite to the double-row outer rolling surface, and between both rolling surfaces of the inner member and the outer member. A double row rolling element housed in a freely rollable manner, a seal mounted in an opening of an annular space formed between the outer member and the inner member, and an inner end of the outer member A non-magnetic synthetic resin is formed by injection molding, and the rotational speed A sensor holder in which a seal is embedded, and an inner seal of the seals is disposed opposite to each other, and an annular seal plate having a substantially L-shaped cross section, and an outer diameter of the inner ring And a slinger having a magnetic encoder in which magnetic poles N and S are alternately magnetized at equal intervals in the circumferential direction. And the sealing plate is formed of a cylindrical part insert-molded in the sensor holder and an inner diameter part extending in a radial direction from the cylindrical part, and the steel plate is formed into a substantially L-shaped cross section by pressing. In the wheel bearing device with a rotational speed detection device comprising a metal core and a seal member integrally joined to the inner diameter part of the metal core, the rotational speed sensor of the cylindrical part of the metal core is disposed. A window that opens radially outward is provided in the region, and the resin material of the sensor holder wraps around and fills in the window, and the detection surface of the rotational speed sensor is flush with the outer diameter side opening end of the window. The window is formed so that all positions of the sensor element surface of the rotational speed sensor are exposed, and the circumferential width of the window is equal to or less than the width of two magnetic poles of the magnetic encoder. The axial width of the window is not more than two-thirds of the axial width of the cylindrical portion of the core metal, and the width from the inner edge of the window to the edge of the cylindrical portion of the core metal is not less than 1 mm. Since the metal material is not interposed between the opposing surfaces of the rotational speed sensor and the magnetic encoder, the magnetic lines of force generated from the magnetic encoder are suppressed from being generated by the magnetic encoder while suppressing the generation of eddy current during the rotational operation. Passing through the window, rotation speed sensor and magnet The spacing between the air encoder and the magnetic encoder can be narrowed, the magnetic flux between the magnetic encoder and the rotation speed sensor can be secured, and the adhesion between the core metal and the resin mold of the sensor holder can be secured. While improving the detection accuracy of a speed sensor, reliability can be improved.

  An outer member integrally having a vehicle body mounting flange for mounting to a suspension device on the outer periphery, a double row outer rolling surface formed integrally on the inner periphery, and a wheel mounting flange for mounting a wheel on one end A hub wheel integrally formed and having an inner rolling surface facing one of the outer rolling surfaces of the double row on the outer periphery, and a small-diameter step portion extending in the axial direction from the inner rolling surface, and the hub wheel An inner member comprising an inner ring that is press-fitted into a small-diameter step portion and has an outer race formed with an inner race surface facing the other of the outer row raceways in the double row, and both the inner member and the outer member. A double row rolling element housed between the rolling surfaces so as to be freely rollable, a seal attached to an opening of an annular space formed between the outer member and the inner member, and the outer member A non-magnetic synthetic resin is formed by injection molding and is attached to the inner side end. A sensor holder in which a seal is embedded, and an inner seal of the seals is disposed opposite to each other, and an annular seal plate having a substantially L-shaped cross section, and an outer diameter of the inner ring And a slinger having a magnetic encoder in which magnetic poles N and S are alternately magnetized at equal intervals in the circumferential direction. And the sealing plate is formed of a cylindrical part insert-molded in the sensor holder and an inner diameter part extending in a radial direction from the cylindrical part, and the steel plate is formed into a substantially L-shaped cross section by pressing. In the wheel bearing device with a rotational speed detection device comprising a cored bar and a seal member integrally joined to the inner diameter part of the cored bar, the cored bar is made of a cold-rolled steel plate with a rust-proof treatment, A window that opens radially outward is provided in a region where the rotational speed sensor of the cylindrical portion is disposed, and the resin material of the sensor holder wraps around and fills in the window, and the detection surface of the rotational speed sensor Is arranged so as to be flush with the opening end of the outer diameter side of the window, and the window is formed so that all positions of the sensor element surface of the rotational speed sensor are exposed, and the circumferential direction of the window The width is formed to be equal to or less than the width of two magnetic poles of the magnetic encoder, the axial width of the window is equal to or less than two thirds of the axial width of the cylindrical portion of the core metal, and the inner diameter of the core metal from the inner edge of the window The width to the edge of the cylindrical portion is set to be 1 mm or more.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a wheel bearing device with a rotational speed detection device according to the present invention, FIG. 2 is an enlarged view of a main part of FIG. 1, and FIG. FIG. 4 is an enlarged view of a main part of FIG. In the following description, the side closer to the outer side of the vehicle in a state assembled to the vehicle is referred to as the outer side (left side in the drawing), and the side closer to the center is referred to as the inner side (right side in the drawing).

  This wheel bearing device with a rotational speed detection device is called a third generation structure for driving wheels, and is constituted by unitizing the hub wheel 1, the double row rolling bearing 2 and the constant velocity universal joint 8. The double-row rolling bearing 2 includes an outer member 3, an inner member 4, and double-row rolling elements (balls) 5 and 5.

  The outer member 3 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and a vehicle body mounting flange 3b to be attached to a knuckle (not shown) constituting a suspension device is integrally formed on the outer periphery. And double row outer rolling surfaces 3a, 3a are integrally formed on the inner periphery. And these double row outer side rolling surfaces 3a and 3a are hardened in the surface hardness of the range of 58-64HRC by induction hardening.

  On the other hand, the inner member 4 includes a hub wheel 1 and an inner ring 6 fixed to the hub wheel 1. The hub wheel 1 integrally has a wheel mounting flange 7 for mounting a wheel (not shown) at an end portion on the outer side, and on the outer side (on the outer side facing the double-row outer raceway surfaces 3a and 3a on the outer periphery). On the other hand, an inner rolling surface 1a and a cylindrical small-diameter step portion 1b extending in the axial direction from the inner rolling surface 1a are formed, and a serration (or spline) 1c for torque transmission is formed on the inner periphery. . Hub bolts 7 a are implanted at equal circumferential positions on the wheel mounting flange 7.

  The hub wheel 1 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the inner rolling surface 1a and the small diameter step from the base portion 7b of the wheel mounting flange 7 with which the outer seal 10 described later is in sliding contact. The surface hardness is hardened to a range of 58 to 64 HRC by induction hardening over the portion 1b. In addition, the crimping part 1d mentioned later is made into the surface hardness after forging by non-hardening.

  The inner ring 6 is formed with an inner side (other side) inner rolling surface 6a facing the double row outer rolling surfaces 3a and 3a on the outer periphery, and a small diameter step portion 1b of the hub wheel 1 via a predetermined scissors. It is press-fitted. The inner ring 6 is fixed to the hub wheel 1 in the axial direction by a caulking portion 1d formed by plastically deforming the end of the small-diameter stepped portion 1b radially outward. The inner ring 6 and the rolling element 5 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC up to the core part by quenching.

  Between the double-row outer raceway surfaces 3a and 3a of the outer member 3, and the inner raceway surface 1a of the hub wheel 1 and the inner raceway surface 6a of the inner ring 6 facing these, the double-row rolling elements 5 and 5 are provided. Is held by the cages 9 and 9 so as to be freely rollable. The end surface on the small diameter side (front side) of the inner ring 6 abuts with the shoulder portion of the hub wheel 1 in a butted state to constitute a so-called back-to-back type double-row angular ball bearing. Further, seals 10 and 11 are attached to the opening portion of the annular space formed between the outer member 3 and the inner member 4, and leakage of the lubricating grease sealed inside the bearing and the inside of the bearing from the outside. Prevents intrusion of rainwater and dust.

  The constant velocity universal joint 8 includes an outer joint member 12, a joint inner ring 13, a cage 14 and a torque transmission ball 15. The outer joint member 12 integrally includes a cup-shaped mouth portion 16, a shoulder portion 17 that forms the bottom portion of the mouth portion 16, and a shaft portion 18 that extends from the shoulder portion 17 in the axial direction. A serration 18a that engages with the serration 1c of the hub wheel 1 is formed on the outer periphery of the shaft portion 18, and a male screw 18b is formed at the end of the serration 18a. The outer joint member 12 is fitted into the hub wheel 1 through the serrations 1c and 18a until the end surface of the crimping portion 1d and the shoulder portion 17 abut each other, and the hub wheel is fixed by the fixing nut 19 fastened to the male screw 18b. 1 and the outer joint member 12 are unitized so that torque can be transmitted and detachable.

  In the present embodiment, the sensor holder 20 is attached to the inner end of the outer member 3. The inner seal 11 is attached to an opening of an annular space formed between the sensor holder 20 and the inner ring 6. As shown in FIG. 3, the seal 11 includes an annular seal plate 21 having a substantially L-shaped cross section, a slinger 22, and a pulsar ring 23 externally fitted to the slinger 22, and is disposed to face each other. ing. The seal plate 21 is vulcanized and bonded to a cored bar 24 composed of a cylindrical part 24 a insert-molded in the sensor holder 20, an inner diameter part 24 b extending radially from the cylindrical part 24 a, and an inner diameter part 24 b of the cored bar 24. Etc., and a sealing member 25 joined together.

  The core metal 24 is formed by press-working a cold-rolled steel plate (JIS standard SPCC system or the like) subjected to rust prevention. The seal member 25 is made of an elastic member such as synthetic rubber, and has a main lip 25a and a grease lip 25b integrally.

  The slinger 22 is formed by pressing an austenitic stainless steel plate (JIS standard SUS304 type or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC type or the like). It has a cylindrical portion 22a that is press-fitted into a diameter, and a vertical plate portion 22b that extends radially outward from the cylindrical portion 22a, and a radial lip 26 is integrally joined to the end portion of the vertical plate portion 22b by vulcanization adhesion. Has been.

  The pulsar ring 23 includes a core metal 27 press-fitted into the cylindrical portion 22a of the slinger 22 and a magnetic encoder 28 joined integrally to the outer diameter portion of the core metal 27 by vulcanization adhesion. The core metal 27 is made of a ferromagnetic steel plate, for example, a ferritic stainless steel plate (JIS standard SUS430 or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC or the like), and is pressed. The cross section is formed in a substantially U shape by processing. The main lip 25 a and the grease lip 25 b of the seal member 25 are slidably contacted with the core metal 27, and the radial lip 26 of the slinger 22 is slidably contacted with the core metal 24 of the seal plate 21. On the other hand, the magnetic encoder 28 is composed of a rubber magnet in which a 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, and a rotary encoder for detecting the rotational speed of the wheel. Is configured.

  By constructing such a seal 11, it is possible to prevent the pulsar ring 23 from being contaminated by dust and the like, and the rolling element 5 and each rolling element by the main lip 25 a and the grease lip 25 b of the seal plate 21 slidably contacting the pulsar ring 23. Since it is isolated from the surface, it is possible to prevent metal wear powder or the like generated by the rotation of the rolling element 5 from adhering to the pulsar ring 23, and it is possible to avoid a decrease in detection accuracy.

  In the present embodiment, the sensor holder 20 is formed of a nonmagnetic resin material such as polyphenylene sulfide (PPS), and a rotational speed sensor 29 facing the magnetic encoder 28 via a predetermined radial gap (air gap) is embedded. Has been. This rotational speed sensor 29 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. IC. Thereby, it is possible to detect the rotational speed with high reliability at low cost. The sensor holder 20 can be exemplified by synthetic resin such as PA (polyamide) 66 and polybutylene terephthalate (PBT) other than the above-described materials.

  A female connector 30 for connecting the rotational speed sensor 29 and a harness (not shown) connected to an electronic circuit of the vehicle body is integrally formed at a predetermined circumferential position of the sensor holder 20. The connector 30 is formed with a recess 30a, and is fitted through a predetermined shimiro so as to cover the inner side end of the outer member 3. Further, the connector 30 protrudes radially outward at a predetermined angle. As a result, when connecting the harness, no pressure input is directly applied to the connector 30 and this pressure input is received at the end of the outer member 3. There is provided a wheel bearing device with a rotational speed detection device capable of detecting a desired rotational speed while improving the reliability and assembling performance without deteriorating the positional accuracy of the rotational speed sensor 29 and improving the assembly accuracy. it can.

  Here, in the cylindrical portion 24a of the cored bar 24, a window 31 that opens radially outward is provided in a region where the rotational speed sensor 29 is disposed, as shown in FIG. The window 31 is filled with the resin material of the sensor holder 20 described above, and the detection surface of the rotational speed sensor 29 is arranged so as to be flush with the outer diameter side opening end of the window 31. Yes. As a result, no metal material is interposed between the opposed surfaces of the rotation speed sensor 29 and the magnetic encoder 28, and therefore, the magnetic lines of force generated from the magnetic encoder 28 while suppressing the generation of eddy currents during the rotation operation cause the window 31 of the core bar 24. And the interval between the rotational speed sensor 29 and the magnetic encoder 28 can be narrowed, and the detection accuracy of the rotational speed sensor 29 can be increased.

  In the present embodiment, the window 31 is formed by exposing all positions where the sensor element (crystal) 32 surface (shown by cross-hatching in the figure) of the rotational speed sensor 29 is exposed, and its circumferential width is 2 magnetic poles. If it is more than the minute, the strength of the cored bar 24 will be insufficient, and moisture will easily enter, so the circumferential width is formed to be equal to or less than the width of the two magnetic poles of the magnetic encoder 28. Further, the axial width of the window 31 is not more than two-thirds of the axial width of the cylindrical portion 24a of the core metal 24, and the edge width d from the inner edge of the window 31 to the end edge of the cylindrical portion 24a of the core metal 24 is 1 mm. It is set to be above.

  Thus, by defining the size and shape of the window 31 to a predetermined value, a reasonable magnetic material such as a cold rolled steel plate having a low material price and good workability can be used for the cored bar 24, and Ensuring the magnetic flux between the magnetic encoder 28 and the rotation speed sensor 29 and ensuring the adhesion between the metal core 24 and the resin mold of the sensor holder 30 can both be achieved, and the reliability can be improved.

  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.

  A wheel bearing device with a rotation speed detection device according to the present invention is a wheel bearing device in which an active type rotation speed detection device including a magnetic encoder and a rotation speed sensor including a magnetic detection element such as a Hall element is incorporated. Can be applied.

It is a longitudinal section showing one embodiment of a wheel bearing device concerning the present invention. It is a principal part enlarged view of FIG. It is a perspective view which shows the core metal simple substance concerning this invention. It is a principal part enlarged view of FIG. It is a longitudinal cross-sectional view which shows the conventional wheel bearing apparatus with a rotational speed detection apparatus. It is a principal part enlarged view of FIG. It is a perspective view which shows the metal core simple substance of FIG. It is a perspective view which shows typically the mode of the magnetic force line discharge | released from the pulsar ring of FIG.

Explanation of symbols

1 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheel 1a, 6a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 1b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・.... Small diameter step 1c, 18a ... Serration 1d ... Caulking part 2 ...・ ・ ・ ・ ・ ・ ・ ・ Double row rolling bearing 3 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outside member 3a ・ ・ ・ ・ ・ ・ ・ ・ Outside Rolling surface 3b .... Body mounting flange 4 ... Inner member 5 ...・ ・ ・ ・ ・ ・ ・ ・ ・ Rolling element 6 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 6 b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Small diameter part 7 ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 7a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub bolt 7b ・ ・ ・············ Base 8 ······················································································ 10 ... Outer side seal 11 ... Inner side seal 12 ... ········· Outer joint member 13 ······················································································・ ・ ・ ・ ・ Torque transmission ball 16 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mouse part 17 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Shoulder part 18 ········· Shaft 18b ···································································· Nut 20 ... Sensor holder 21 ... ... Seal plate 22 ... Slinger 22a, 24a ... Cylindrical part 22b ...・ ・ Standing plate 23 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Pulsar ring 24, 27 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Core 24b ……・ ・ ・ ・ Inner diameter 25 ・ ・ ・ ・ ・ ・ ・ ・ Seal member 25a ・ ・ ・ ・ ・ ・ ・ ・ Main lip 25b ・ ・ ・ ・ ・ ・ ・ ・Grease lip 26 Radial lip 28 Magnetic encoder 29 ............ Rotational speed sensor 30 ......... Connector 30a ......... Recess 31 ... ... window 31a ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner edge 32 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Sensor element 50 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Double row rolling Bearing 51 ... Outer member 51a ... Outer rolling surface 51b ... .... Body mounting flange 52 ... Inner member 53 ... Ball 54 ...・ ・ ・ ・ ・ ・ ・ ・ ・ Knuckle 55 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheel 55a, 56a ...... ・ ・ ・ ・ ・ Inner rolling surface 55b ..... Small diameter step 55c, 68a ... Serration 55d ...... Wheel mounting flange 56 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 57 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Clamping part 58 ... Cage 59 ... Outer seal 60 ... Inner side seal 61 ... Constant velocity universal joint 62 ... Outer joint member 63 ... Joint inner ring 64 ... Cage 65 ...・ ・ ・ ・ Torque transmission ball 66 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mouse part 67 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Shoulder 68 ・ ・ ・ ・ ・ ・········ Shaft 68b ············································································・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ First seal ring 71 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ Second seal ring 72, 77 ... Core 72a ... Cylindrical part 72b ...・ ・ ・ ・ ・ Inner diameter part 73 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal member 73a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Main lip 73b ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ Auxiliary lip 74 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Slinger 75 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Radial lip 76 ・ ・ ・ ・ ・Pulsar ring 78 ... Multipole rotor 79 ... Sensor holder 80 Magnetic sensor 81 ... Connector 82 ... Window 83 ... Resin exterior d ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Window width

Claims (5)

An outer member integrally having a vehicle body mounting flange for mounting to a suspension device on the outer periphery, and an outer rolling surface of a double row integrally formed on the inner periphery;
From a hub wheel integrally having a wheel mounting flange for mounting a wheel at one end and having a 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 An inner member in which a double row inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery,
A double row rolling element housed so as to be freely rollable between both rolling surfaces of the inner member and the outer member;
A seal attached to an opening of an annular space formed between the outer member and the inner member;
A sensor holder mounted on the inner side end of the outer member, formed of nonmagnetic synthetic resin by injection molding, and embedded with a rotational speed sensor;
Among the seals, the inner side seals are arranged to face each other, and are attached to an annular seal plate having a substantially L-shaped cross section and an outer diameter of the inner ring. And a pulsar ring having a magnetic encoder with magnetic poles N and S magnetized alternately at equal intervals in the circumferential direction, and externally fitted to the slinger.
The seal plate includes a cylindrical portion that is insert-molded in the sensor holder, and an inner diameter portion that extends in a radial direction from the cylindrical portion, and a metal core that is formed into a substantially L-shaped cross section by pressing a steel plate, and the core In a wheel bearing device with a rotational speed detection device comprising a seal member integrally joined to an inner diameter portion of gold,
A window that opens radially outward is provided in a region of the cylindrical portion of the metal core where the rotational speed sensor is disposed, and the resin material of the sensor holder is wrapped around and filled in the window. Is arranged so that the detection surface of the window is flush with the outer diameter side opening end of the window, and the window is formed so that all positions of the sensor element surface of the rotational speed sensor are exposed. The circumferential width is formed to be equal to or less than the width of two magnetic poles of the magnetic encoder, the axial width of the window is equal to or less than two-thirds of the axial width of the cylindrical portion of the core metal, and the inner edge of the window A wheel bearing device with a rotational speed detection device, characterized in that the width to the edge of the cylindrical portion of the core metal is set to 1 mm or more.   The wheel bearing device with a rotation speed detection device according to claim 1, wherein the core metal is formed of a cold-rolled steel plate that has been rust-proofed.   A connector for connecting the rotational speed sensor and the harness connected to the electronic circuit is provided at a predetermined circumferential position of the sensor holder so as to protrude radially outward at a predetermined angle, and a recess is provided in the connector. The wheel bearing device with a rotational speed detection device according to claim 1, wherein the wheel bearing device is formed and is fitted through a predetermined shimiro so that the recess covers an end on the inner side of the outer member.   The pulsar ring is press-fitted into the cylindrical portion of the slinger, and has a metal core formed into a substantially U-shaped cross section by pressing from a steel plate of a magnetic material, and the magnetic encoder is attached to the outer diameter portion of the metal core The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 3, which is integrally joined.   The wheel bearing device with a rotational speed detecting device according to claim 4, wherein the seal member integrally has a plurality of seal lips, and the seal lips are slidably contacted with a core metal of the pulsar ring.

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