JP2008286269A - Bearing device for wheel equipped with rotation speed detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a wheel equipped with a rotation speed detection device, which secures drawing proof strength of a sensor holder, improves the airtightness of a fitting portion and the sealing performance of a seal, and improves the reliability by maintaining the detection precision. <P>SOLUTION: In the bearing device for the wheel equipped with the rotation speed detection device, a seal 11 comprises a seal plate 21 consisting of a core bar 24 insert-molded by a sensor holder 20 and a seal member 25, and a slinger 22 disposed oppositely thereto. A pulsar ring 23 is pressed in the slinger 22. A magnetic encoder 28 is joined to the outside diameter portion. The magnetic encoder 28 faces a rotation speed sensor 29 embedded in the sensor holder 20. Supposing that a mass of the sensor holder 20 is m, and vibration acceleration is a, the minimum drawing force Fmin of the sensor holder 20 with respect to an outward member 3 is determined by a relational expression Fmin=m×a, and the drawing force is set not less than Fmin. <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. 4 is known as an example of such a wheel bearing device with a rotational speed detection device. The wheel bearing device 50 with a rotational speed detection device includes an outer member 51, an inner member 53 inserted into the outer member 51 via double rows of balls 52, and an end of the outer member 51. And a rotational speed detecting device 54 mounted on the head.

  The outer member 51 integrally has a vehicle body mounting flange 51b to be attached to a knuckle (not shown) constituting a suspension device on the outer periphery, and double row outer rolling surfaces 51a, 51a are integrated on the inner periphery. Is formed.

  On the other hand, the inner member 53 includes a hub wheel 55 and an inner ring 56 fixed to the hub wheel 55. The hub wheel 55 integrally has a wheel mounting flange 57 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 and 51a on the outer periphery. 55a and a cylindrical small diameter step portion 55b extending in the axial direction from the inner rolling surface 55a are formed. 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. .

  Double rows of balls 52, 52 are disposed between the double row outer raceway surfaces 51 a, 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, which are opposed thereto. It is accommodated and is held by the cages 58 and 58 so as to be freely rollable. In addition, seals 59 and 60 are attached to the opening portion of the annular space formed between the outer member 51 and the inner member 53, 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.

  As shown in FIG. 5, the rotational speed detection device 54 includes a sensor holder 62 in which a magnetic sensor 61 is embedded, and a seal 60. The sensor holder 62 is insert-molded integrally with a metal core 65 constituting the seal 60 by injection molding from synthetic resin.

  The seal 60 is configured by combining a first seal ring 63 and a second seal ring 64. The first seal ring 63 includes a cored bar 65 formed by a single rigid ring, and a seal member 66 attached to the cored bar 65. The cored bar 65 includes a fitting cylindrical portion 65a fitted in the end portion of the outer member 51, an outer flange portion 65b extending radially inward from the cylindrical portion 65a, and an axially outward direction from the flange portion 65b. It has a moisture intrusion preventing cylindrical portion 65c extending to the left and an inner flange portion 65d extending radially inward from the cylindrical portion 65c. And the sealing member 66 is adhere | attached on the inner peripheral part of this inner side flange part 65d.

  The second seal ring 64 includes a slinger 67 attached to the inner ring 56 and having a substantially L-shaped cross section, and a pulsar ring 68 that is externally fitted to the slinger 67. The slinger 67 has a cylindrical portion 67a that is press-fitted into the small-diameter portion 56b of the inner ring 56, and an outward flange portion 67b that extends radially outward from the cylindrical portion 67a. An elastic seal 69 having an axial lip 69a that is in sliding contact with the end face is provided.

  The pulsar ring 68 includes an annular support member 70 and a magnetized body 71 bonded thereto. The support member 70 is a small-diameter cylindrical portion 70a that is press-fitted into the cylindrical portion 67a of the slinger 67, a connecting portion 70b that extends radially outward from the small-diameter cylindrical portion 70a, and an axially inward extending from the connecting portion 70b. The inner ring 56 includes a large-diameter cylindrical portion 70c formed with a larger diameter than the large-diameter portion 56c. The magnetized body 71 is bonded to the large diameter cylindrical portion 70c. This magnetized body 71 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. The magnetic sensor 61 is disposed so as not to contact the portion 65c.

  The seal member 66 includes a slinger side lip 66a slidably in contact with the outward flange portion 67b of the slinger 67, a pair of radial lips 66b and 66c slidably in contact with the small diameter cylindrical portion 70a of the support member 70, and the support member 70. And a pulsar side lip 66d that is in sliding contact with the connecting portion 70b.

  The sensor holder 62 is opposed to the end surface of the outer member 51 through a slight axial clearance, and an annular recess 72 is formed so as to expose a part of the outer diameter of the fitting cylindrical portion 65a of the cored bar 65. Has been. An O-ring 73 is elastically mounted in the recess 72, and a disc-like cover 74 having a hole diameter smaller than the outer diameter of the slinger 67 is mounted on the outer end surface of the sensor holder 62.

In the rotational speed detection device 54, after the first seal ring 63 and the pulsar ring 68 are combined, the support member 70 of the pulsar ring 68 is press-fitted into the slinger 67, so that all components including the O-ring 73 are assembled in advance. When the whole is pressed in the axial direction, the fitting cylindrical portion 65a of the core metal 65 is fitted into the end of the outer member 51, and the cylindrical portion 67a of the slinger 67 is a small diameter portion of the inner ring 56. It is press-fitted into 56b. With such a configuration, separation of the cored bar 65 and the sensor holder 62 can be prevented, and intrusion of moisture from the boundary between the cored bar 65 and the sensor holder 62 can be prevented.
JP 2006-183701 A

  However, such a conventional wheel bearing device 50 with a rotational speed detection device is subjected to an impact load or vibration during traveling of the vehicle. When used under such conditions, the sensor holder 62 may move from the outer member 51. Thereby, not only the airtightness of the fitting portion and the sealability of the seal 60 are deteriorated, but also accurate detection may not be performed. In particular, when this metal sensor 65 is insert-molded into the metal core 65 and is metal-fitted to the outer member 51 via the metal core 65, the surface of the fitting portion is generally used. Although it is considered that the fitting force is increased by improving the roughness and dimensional accuracy, there is a limit in terms of cost effectiveness such as an increase in processing man-hours and management man-hours.

  The present invention has been made in view of such circumstances, ensuring the pull-out strength of the sensor holder, improving the air tightness of the fitting portion and the sealing performance of the seal, and maintaining the detection accuracy and improving the reliability. An object of the present invention is to provide an improved wheel bearing device with a rotational speed detection device.

  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 Attached to the end on the inner side and formed of synthetic resin by injection molding. A seal holder in which the inner seal is an annular seal plate, a slinger formed in a substantially L-shaped cross section and press-fitted into the outer diameter of the inner ring, and the slinger And a pulsar ring provided with a magnetic encoder in which the characteristic in the circumferential direction changes alternately and at equal intervals on the outer diameter portion, and the exposed portion of the seal plate is the end of the outer member. And a metal core formed by press working from a steel plate and insert-molded with the sensor holder, and a seal member integrally joined to the metal core and having a side lip and a radial lip. The side lip of the seal member is slidably contacted with the slinger and / or the pulsar ring, and the magnetic encoder and the rotational speed sensor are connected via a radial clearance. In the wheel bearing device with a rotational speed detection device opposed to each other, when the mass of the sensor holder is m and the vibration acceleration is a, the minimum pulling force Fmin of the sensor holder with respect to the outer member is Fmin = mx It is prescribed | regulated by the relational expression of a, and the extraction force of the said sensor holder is set to Fmin or more.

  In this way, a seal attached to the opening of the annular space formed between the outer member and the inner member, and an end on the inner side of the outer member, synthetic resin is formed by injection molding A sensor holder in which the rotational speed sensor is embedded, and an inner seal of the seals is an annular seal plate and a slinger formed in a substantially L-shaped cross section and press-fitted into the outer diameter of the inner ring, And a pulsar ring that is externally fitted to the slinger and has a magnetic encoder in which the characteristic in the circumferential direction changes alternately and at equal intervals on the outer diameter portion, and the exposed portion of the seal plate is the outer member. A metal core that is fitted into the end and formed by press working from a steel plate and the sensor holder is insert-molded; and a seal member that is integrally joined to the metal core and has a side lip and a radial lip. And a sensor holder in a wheel bearing device with a rotational speed detection device in which the side lip of the seal member is slidably contacted with a slinger, a pulsar ring, or both, and the magnetic encoder and the rotational speed sensor are opposed to each other via a radial clearance. When the mass of m is m and the vibration acceleration is a, the minimum pulling force Fmin of the sensor holder with respect to the outer member is defined by the relational expression Fmin = m × a, and the pulling force of the sensor holder is set to Fmin or more. Therefore, it is possible to secure the pull-out strength of the sensor holder, improve the airtightness of the fitting part and the sealing performance of the seal, and maintain the detection accuracy and improve the reliability, and the wheel bearing device with a rotational speed detection device. Can be provided.

  Further, as in the invention according to claim 2, if the fitting shimiro of the outer member and the core metal is adjusted so as to satisfy the relational expression, the surface roughness and dimensions of the fitting portion are adjusted. A desired fitting force can be obtained without restricting the precision more strictly than necessary, and an increase in processing man-hours and management man-hours can be suppressed.

  According to a third aspect of the present invention, the core metal is formed by pressing from a steel plate and is press-fitted into an end portion of the outer member, and a radial direction from the outer diameter cylindrical portion. An inwardly extending vertical plate portion, an inner diameter cylindrical portion extending from the vertical plate portion toward the inner side, and an inner diameter portion extending radially inward from the inner diameter cylindrical portion, the seal member being integrated with the inner diameter portion It may be joined.

  According to a fourth aspect of the present invention, a small-diameter portion and a large-diameter portion are formed on the outer diameter of the inner ring, and the slinger is pressed into the small-diameter portion, and a radial direction from the cylindrical portion An upright plate portion extending outward, and an inner diameter portion of a support member constituting the pulsar ring is press-fitted and fixed to the cylindrical portion, and the support member extends from the inner diameter portion radially outward, A cylindrical outer diameter portion extending from the upright plate portion to the bearing inward side and having a slightly larger diameter than the large diameter portion, and the magnetic encoder is joined to the outer diameter portion, If the side lip of the seal member is slidably contacted with the slinger and the upright plate portion of the support member, and the radial lip is slidably contacted with the inner diameter portion of the pulsar ring, the sealing performance is improved and the pulsar ring is caused by rainwater or dust. It can prevent getting dirty.

  According to a fifth aspect of the present invention, in the magnetic encoder, the magnetic powder is mixed in the elastomer, the magnetic poles N and S are alternately magnetized in the circumferential direction, and the core metal is nonmagnetic. As long as it is made of austenitic stainless steel rod, stable speed detection is possible even if the inner diameter cylindrical part of the cored bar is interposed between the rotational speed sensor and the magnetic encoder, without affecting the sensing performance of the rotational speed sensor. It can be performed.

  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 Is attached to the part and formed by injection molding of synthetic resin to wrap the rotational speed sensor. An inner seal out of the seals, a slinger formed in a substantially L-shaped cross section and press-fitted into the outer diameter of the inner ring, and an outer fit to the slinger And a pulsar ring provided with a magnetic encoder whose characteristics in the circumferential direction are alternately and equally spaced at the outer diameter portion, and the exposed portion of the seal plate is located at the end of the outer member. It is formed of a core metal that is fitted and formed by press working from a steel plate and the sensor holder is insert-molded, and a seal member that is integrally joined to the core metal and integrally includes a side lip and a radial lip. The side lip of the member is slidably contacted with the slinger and / or pulsar ring, and the magnetic encoder and rotational speed sensor are opposed to each other via a radial clearance. In the wheel bearing device with a rotational speed detection device, when the mass of the sensor holder is m and the vibration acceleration is a, the minimum pulling force Fmin of the sensor holder with respect to the outer member is Fmin = m × a Since it is defined by the relational expression and the pulling force of the sensor holder is set to Fmin or more, the pulling strength of the sensor holder is secured, the air tightness of the fitting part and the sealing performance of the seal are improved, and the detection accuracy is improved. It is possible to provide a wheel bearing device with a rotation speed detection device that is maintained and improved in reliability.

  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 Is attached to the inner side end of the plastic and is formed by injection molding of a synthetic resin. The inner seal of the seals is composed of an annular seal plate, a slinger having a substantially L-shaped cross section, and a pulsar ring that is externally fitted to the slinger. An outer diameter cylindrical portion in which an exposed portion of the plate is fitted into an end portion of the outer member, a standing plate portion extending radially inward from the outer diameter cylindrical portion, and an inner side from the standing plate portion An inner diameter cylindrical portion that extends, and an inner diameter portion that extends radially inward from the inner diameter cylindrical portion, and is formed by pressing from a steel plate, and the sensor holder is insert-molded. The seal member is integrally joined and has a side lip and a radial lip, and the side lip of the seal member is slidably contacted with the slinger and / or the pulsar ring. In a wheel bearing device with a rotational speed detection device in which a magnetic encoder and a rotational speed sensor are opposed to each other via a radial clearance, when the mass of the sensor holder is m and the vibration acceleration is a, the sensor for the outer member The minimum pulling force Fmin of the holder is defined by a relational expression of Fmin = m × a, and the fitting squeeze between the outer member and the cored bar is adjusted so that this relational expression is satisfied, and the sensor holder is pulled out. The force is set to Fmin or higher.

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. 3 is a drawing state of a sensor holder. It is explanatory drawing. 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, 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 one (outer side) of the outer raceway surfaces 3a and 3a of the double row on the outer periphery. And a cylindrical small-diameter step portion 1b extending in the axial direction from the inner rolling surface 1a, and a serration (or spline) 1c for torque transmission is formed on the inner periphery. . Note that hub bolts 7 a for attaching the wheels are planted at equal circumferential positions of the wheel mounting flanges 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 includes a base 7b of a wheel mounting flange 7 on which an outer-side seal 10 to be described later comes into sliding contact, including the inner rolling surface 1a. The surface hardness is hardened in the range of 58 to 64 HRC by induction hardening over the small diameter step 1b.

  The inner ring 6 is formed on the outer periphery with an inner rolling surface 6a facing the other (inner side) of the double row outer rolling surfaces 3a, 3a, and a small diameter step portion 1b of the hub wheel 1 via a predetermined squeezing. It is press-fitted and fixed. 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 (or spline) 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. Then, until the end face of the inner ring 6 and the shoulder portion 17 abut each other, the outer joint member 12 is fitted into the hub ring 1 via the serrations 1c and 18a, and the hub ring 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.

  The sensor holder 20 constituting the rotational speed detection device is attached to the inner side 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. 2, the seal 11 includes an annular seal plate 21 and a slinger 22 each having a substantially L-shaped cross section, and is disposed to face each other. The pulsar ring 23 is externally fitted to the slinger 22.

  The seal plate 21 includes a cored bar 24 and a seal member 25 integrally joined to the cored bar 24 by vulcanization adhesion or the like. The metal core 24 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). 3, an outer diameter cylindrical portion 24a fitted in the end portion, an inner diameter cylindrical portion 24c extending in the axial direction from the outer diameter cylindrical portion 24a via the upright plate portion 24b, and a radially inward direction from the inner diameter cylindrical portion 24c. And an inner diameter portion 24d extending in the direction. The outer diameter cylindrical portion 24a is formed so as to protrude from the end portion of the outer member 3, and the sensor holder 20, which will be described later, is insert-molded on the core metal 24 and integrally coupled. The cored bar 24 is preferably formed of a non-magnetic austenitic stainless steel plate so as not to adversely affect the sensing performance of the rotational speed sensor 29.

  The seal member 25 is made of an elastic member such as synthetic rubber, and is integrally joined to the inner diameter portion 24d of the core metal 24 by vulcanization adhesion or the like, and the side lips 25a and 25b and the inner diameter portion 24d are disposed on both sides of the inner diameter portion 24d. A pair of radial lips 25c and 25d are provided on the inner edge of the.

  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 the outer diameter of the portion 6b, and a standing plate portion 22b that extends radially outward from the cylindrical portion 22a. The elastic lip 26 slidably in contact with the end face of the inner ring 6 is integrally joined by vulcanization adhesion or the like to prevent moisture such as rainwater from entering the bearing from the fitting portion.

  The pulsar ring 23 includes a support member 27 that is press-fitted into the slinger 22 and a magnetic encoder 28 that is integrally joined to the outer diameter portion of the support member 27 by vulcanization adhesion. The support member 27 is made of a ferromagnetic steel plate, for example, a ferritic stainless steel plate (JIS standard SUS430 type or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC type or the like), and is pressed. A cylindrical inner diameter portion 27a formed by machining and press-fitted into the cylindrical portion 22a of the slinger 22, a standing plate portion 27b extending radially outward from the inner diameter portion 27a, and a bearing inward side from the standing plate portion 27b And has a cylindrical outer diameter portion 27 c formed slightly larger in diameter than the large diameter portion 6 c of the inner ring 6. The side lips 25a and 25b of the seal member 25 are slidably contacted with the slinger 22 and the standing plate portions 22b and 27b of the support member 27, respectively, and the pair of radial lips 25c and 25d are slidably contacted with the cylindrical portion 27a of the support member 27. Has been.

  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. The rotational speed sensor 29 is disposed so as to face the rotational speed sensor 29 with a predetermined radial clearance (air gap) in a range not contacting the inner diameter cylindrical portion 24c of the cored bar 24. Thereby, coupled with the support member 27 made of a ferromagnetic material, the output signal becomes stronger, and stable detection accuracy can be ensured. Moreover, by configuring such a seal 11, it is possible to improve the sealing performance and prevent the pulsar ring 23 from being contaminated by rainwater, dust, or the like.

  In the present embodiment, the sensor holder 20 is made 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 clearance is embedded. 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 resins that can be injection molded, such as PA (polyamide) 66, polybutylene terephthalate (PBT), in addition to the materials described above.

  The sensor holder 20 is opposed to the end surface of the outer member 3 through a slight axial clearance, and an annular recess 30 is formed so as to expose a part of the outer diameter of the outer diameter cylindrical portion 24a of the cored bar 24. Has been. An O-ring 31 is elastically mounted in the recess 30 to improve the airtightness of the fitting portion between the outer member 3 and the cored bar 24, and the inner end face of the sensor holder 20 has a smaller diameter than the outer diameter of the slinger 22. A disc-shaped cover 32 having a hole diameter of 2 mm is mounted, and a slight radial clearance is formed between the disc-shaped cover 32 and the shoulder portion 17 of the outer joint member 12 to form a labyrinth seal 33 to provide a sealing property. Is secured.

  In the rotational speed detection device, after the seal plate 21 and the pulsar ring 23 are combined, the slinger 22 is press-fitted into the support member 27 of the pulsar ring 23 so that all the components including the O-ring 31 are assembled in advance. Is pressed in the axial direction, the outer diameter cylindrical portion 24a of the cored bar 24 is fitted into the end of the outer member 3, and the cylindrical portion 22a of the slinger 22 is press-fitted into the small diameter portion 6b of the inner ring 6. The

  In the present embodiment, as an example of the rotational speed detection apparatus, an active type rotational speed detection apparatus including the magnetic encoder 28 and the rotational speed sensor 29 including a magnetic detection element such as a Hall element is illustrated. The rotational speed detection device is not limited to this, and may be, for example, a passive type including a gear, a magnet, and an annular coil wound around.

Here, in the present embodiment, the pulling force of the sensor holder 20 with respect to the outer member 3 is defined by a predetermined relational expression. That is, the pulling-out force of the metal core 24 that is metal-fitted to the outer member 3 is defined by the following equation, and the fitting shimiro between the outer member 3 and the metal core 24 is adjusted. When the minimum pulling force of the metal core 24 against vibration is Fmin, the mass of the sensor holder 20 is m (kg), and the acceleration is a (m / sec ² ), the minimum pulling force Fmin = m × a (N). . For example, when the mass m of the sensor holder 20 is 0.05 kg and the acceleration a is 30 G, Fmin = 0.05 × 30 G = 14.7 N. Here, G is a gravitational acceleration of 9.80665 m / sec ²

  As shown in FIG. 3, since the minimum extraction force Fmin of the cored bar 24 is calculated from the vibration condition loaded on the wheel bearing device in advance and the mass m of the sensor holder 20, the minimum extraction force Fmin is satisfied. In addition, the fitting shimiro between the metal core 24 and the outer member 3, that is, the fitting shimiro calculated from the drawing force determined by the fitting surface pressure, the dimensions of each part, the finished state of the fitting surface, and the like is only adjusted. Thus, the pulling strength of the sensor holder 20 can be secured without restricting the surface roughness and dimensional accuracy of the fitting portion more strictly than necessary. Therefore, it is possible to suppress the increase in processing man-hours and management man-hours, improve the air tightness of the fitting part and the sealing performance of the seal, maintain the detection accuracy and improve the reliability, for wheels with a rotation speed detection device A bearing device can be provided.

  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 wheel bearing device with a rotation speed detection device according to the present invention can be applied to a wheel bearing device in which any type of rotation speed detection device having an inner ring rotation structure is incorporated.

It is a longitudinal cross-sectional view which shows one Embodiment of the wheel bearing apparatus with a rotational speed detection apparatus which concerns on this invention. It is a principal part enlarged view of FIG. It is explanatory drawing which shows the extraction state of the sensor holder 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.

Explanation of symbols

1 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheel 1a, 6a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 1b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・.... Small diameter step 1c, 18a ... Serration 2 ... Double row rolling bearing 3 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer member 3a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer rolling surface 3b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Car body mounting flange 4 ... Inner member 5 ... Rolling element 6 ... .... Inner ring 6b ... Small diameter part 6c ... Large 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 ... ... Cylindrical parts 22b, 24b, 27b ... Standing plate part 23 ... Pulsar ring 24 ... Core metal 24a ... ... Outer diameter cylindrical part 24c ... Inner diameter cylindrical part 24d, 27a ... Inner diameter part 25 ...・ ・ ・ ・ ・ ・ Seal members 25a and 25b ・ ・ ・ ・ ・ ・ Side lips 25c and 25d ・ ・ ・ ・ ・ ・ Radial lip 26 ・ ・ ・ ・ ・ ・··· Elastic lip 27 ········ Support member 27c ············ Outer diameter portion 28 .... Magnetic encoder 29・ ・ ・ ・ ・ ・ ・ ・ ・ Rotational speed sensor 30 ............ Recess 31・ O-ring 32 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Disk cover 33 ・ ・ ・ ・ ・ ・ ・ ・ Labyrinth seal 50 ・ ・ ・ ・ ・ ・ ・ ・········· Wheel bearing device 51 with rotational speed detection device Outer rolling surface 51b ......... Car body mounting flange 52 ......... Ball 53 ...・ ・ ・ ・ ・ Inward member 54 ・ ・ ・ ・ ・ Rotational speed detector 55 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheels 55a, 56a・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 55b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Small diameter step 56 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 56 b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Small diameter portion 56 c・ ・ ・ ・ Large diameter part 57 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 58 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cage 59 Outer seal 60 ... Inner seal 61 ... Magnetic sensor 62 ... sensor holder 63 ... first seal ring 64 ... ········ Second seal ring 65 ········································································・ ・ ・ ・ ・ ・ ・ ・ ・ Outer flange 65c ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ Cylinder 65d for preventing moisture ingress ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner flange 66 ・ ・ ・ ・ ・ ・ Seal Member 66a ··············· Slinger side lip 66b, 66c ··· Radial lip 66d ········· Pulsar side lip 67 ·········· Slinger 67a ······································ ... Outward flange 68 ... Pulsar ring 69 ... Elastic seal 69a ...・ ・ ・ ・ Axial lip 70 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Supporting member 70a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Small diameter cylindrical part 70b ・ ・ ・ ・... ········ 70c ···················································································・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Recess 73 ・ ・ ・ ・ ・ ・ ・ ・ O-ring 74 ・ ・ ・ ・ ・ ・ ・ ・ Disk Cover a ... vibration acceleration Fmin ... minimum pulling force G ...・ ・ ・ ・ ・ Gravity acceleration m ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mass of sensor holder

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 synthetic resin by injection molding, and embedded with a rotational speed sensor;
The seal on the inner side of the seal is formed with an annular seal plate, a slinger formed in a substantially L-shaped cross section and press-fitted into the outer diameter of the inner ring, and is fitted onto the slinger, and a circle is formed on the outer diameter portion. It consists of a pulsar ring provided with a magnetic encoder whose characteristics in the circumferential direction change alternately and at equal intervals.
The seal plate, the exposed portion is internally fitted to the end portion of the outer member, a core metal formed by pressing from a steel plate and the sensor holder is insert-molded, and integrally bonded to the core metal, A seal member having a side lip and a radial lip integrally,
In the wheel bearing device with a rotational speed detection device, the side lip of the seal member is slidably contacted with the slinger or the pulsar ring or both, and the magnetic encoder and the rotational speed sensor are opposed to each other through a radial clearance.
When the mass of the sensor holder is m and the vibration acceleration is a, the minimum pulling force Fmin of the sensor holder with respect to the outer member is defined by a relational expression Fmin = m × a, and the pulling force of the sensor holder is A wheel bearing device with a rotational speed detection device, wherein the wheel bearing device is set to Fmin or more.   The wheel bearing device with a rotational speed detection device according to claim 1, wherein a fitting nip of the outer member and the metal core is adjusted so as to satisfy the relational expression.   The core metal is formed by pressing from a steel plate, and an outer diameter cylindrical portion press-fitted into an end portion of the outer member, a standing plate portion extending radially inward from the outer diameter cylindrical portion, and the standing plate portion 3. The rotation according to claim 1, further comprising an inner diameter cylindrical portion extending from the inner diameter side toward the inner side and an inner diameter portion extending radially inward from the inner diameter cylindrical portion, wherein the seal member is integrally joined to the inner diameter portion. Wheel bearing device with speed detector.   A small-diameter portion and a large-diameter portion are formed on the outer diameter of the inner ring, and the slinger has a cylindrical portion that is press-fitted into the small-diameter portion, and a vertical plate portion that extends radially outward from the cylindrical portion. An inner diameter portion of a support member constituting the pulsar ring is press-fitted and fixed to a portion, the support member extends radially outward from the inner diameter portion, and extends from the standing plate portion toward the bearing inward side. A cylindrical outer diameter portion formed slightly larger than the diameter portion, and the magnetic encoder is joined to the outer diameter portion, and the side lip of the seal member is provided between the slinger and the support member. The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 3, wherein the radial lip is slidably contacted with a plate portion, and the radial lip is slidably contacted with an inner diameter portion of the pulsar ring.   In the magnetic encoder, magnetic powder is mixed in an elastomer, magnetic poles N and S are alternately magnetized in a circumferential direction, and the core metal is formed of a non-magnetic austenitic stainless steel plate. Item 5. A wheel bearing device with a rotational speed detection device according to any one of Items 1 to 4.

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