JP2010089593A - Wheel bearing device with rotation speed sensing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing device with a rotation speed sensing device, reduced in size and weight and enhancing the reliability by preventing any foreign matters from intruding directly into the part of sensing. <P>SOLUTION: The wheel bearing device includes: a cover 17 which is equipped with a fitting part 17a in cylindrical shape to be fitted by pressure to the inner side end of an outer member 5; a flange 17b extending inward in the radial direction from the fitting part 17a and put in tight attachment to the end face 5c of the outer member 5; a bottom part 17c extending inward in the radial direction from the flange 17b; an inside circumferential part 17d in cylindrical shape extending in the axial direction from the bottom part 17c; and a second bottom part 17e extending further inward in the radial direction from the inside circumferential part 17d. The second bottom part 17e and the wall surface 21a of an annular recess 21 in the inner ring 2 confront each other with a certain clearance in the axial direction reserved in between so as to form a labyrinth seal S1, while the inner edge of the second bottom part 17e and the outside surface 21b of the annular recess 21 confront each other with a certain clearance in the radial direction reserved in between so as to form a labyrinth seal S2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wheel bearing device with a rotational speed detection device that rotatably supports a wheel of an automobile or the like and incorporates a rotational speed detection device that detects the rotational speed of the wheel.

  A wheel bearing with a rotation speed detecting device that rotatably supports a vehicle wheel with respect to a suspension device and controls an anti-lock brake system (ABS) to detect the rotation speed of the wheel. 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 adjusting the air gap between the rotational speed sensor and the magnetic encoder and to achieve a more compact design, recently, a bearing for a wheel with a rotational speed detection device that also incorporates the rotational speed sensor in the bearing. A device has been proposed.

  A structure as shown in FIG. 10 is known as an example of such a wheel bearing device with a rotational speed detection device. This rotational speed detection device includes an encoder 51 fitted on the inner ring 50, a sensor holder 53 attached to the end of the outer member 52 so as to face the encoder 51, and a predetermined air to the encoder 51. And a rotation speed sensor 54 facing each other through a gap. The encoder 51 is joined to the side surface of the slinger 57 constituting the seal 56.

  The seal 56 includes a slinger 57 having a substantially L-shaped cross section, and an annular seal plate 58 mounted on the outer member 52 so as to face the slinger 57 and having a substantially L-shaped cross section. The slinger 57 includes a cylindrical portion 57a that is externally fitted to the inner ring 50, and a standing plate portion 57b that extends radially outward from the cylindrical portion 57a. On the other hand, the seal plate 58 includes a metal core 59 fitted into the end of the outer member 52, and a seal member 60 vulcanized and bonded to the metal core 59. The seal member 60 is made of an elastomer such as rubber, and includes a side lip 60a that is in sliding contact with the standing plate portion 57b of the slinger 57, and a grease lip 60b and an intermediate lip 60c that are in sliding contact with the cylindrical portion 57a.

  The sensor holder 53 includes a steel plate cover 55 fitted on the outer member 52 and a synthetic resin holding portion 61 coupled to the bottom portion 55c of the cover 55. The rotation speed sensor is connected to the holding portion 61. 54 is embedded. The cover 55 includes a cylindrical fitting portion 55a fitted on the outer member 52, a flange portion 55b extending radially inward from the fitting portion 55a, and a bottom portion 55c extending axially from the flange portion 55b. It consists of.

The inner end of the cover 55 constituting the sensor holder 53, that is, the inner edge of the circular hole 65 in the bottom portion 55 c, faces the outer peripheral surface of the shoulder portion 66 of the outer joint member 64 through a slight radial clearance, thereby forming a labyrinth seal 67. Is configured. Thus, even during actual running, which is a harsh environment, foreign matter such as magnetic powder can be prevented from entering between the encoder 51 and the detection unit of the rotation speed sensor 54, and the rotation speed of the wheel can be prevented. The reliability of the detection device can be further improved.
JP 2006-145418 A

  However, in this conventional wheel bearing device with a rotational speed detection device, the labyrinth seal is configured such that the outer peripheral surface of the shoulder portion 66 of the outer joint member 64 and the inner edge of the circular hole 65 of the bottom portion 55c of the cover 55 face each other. Since it was 67, the confrontation range which exhibits a labyrinth effect was short, and it was difficult to obtain sufficient sealing performance. Further, since the labyrinth seal 67 is configured between the cover 55 attached to the outer member 52 and the shoulder 66 of the outer joint member 64, the labyrinth seal 67 is affected by the coaxiality and assembly accuracy of each component. It was difficult to precisely define the radial clearance, and there was a limit to obtaining high sealing performance.

  The present invention has been made in view of such circumstances, and is intended for a wheel with a rotational speed detection device that is light and compact, and that prevents foreign matter from directly entering the detection unit and improves reliability. It aims at providing a bearing device.

  In order to achieve such an object, the invention described in claim 1 of the present invention has a vehicle body mounting flange integrally attached to the knuckle 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 An annular cover press-fitted into the outer periphery of the inner side end, and this cover are combined, A sensor holder having a holding part made of synthetic resin in which a rotation speed sensor is embedded, and an inner seal of the seal is fitted into an inner side end of the outer member, and is pressed from a steel plate. A cored bar formed into a substantially L-shaped cross-section by processing, an annular seal plate made of a seal member integrally joined to the cored bar, and press-fitted into the outer diameter of the inner ring facing the seal plate; A slinger having a substantially L-shaped cross section formed by pressing from a steel plate, and an encoder whose characteristics in the circumferential direction change alternately and at equal intervals are joined to the inner side surface of the slinger. In the wheel bearing device with a rotational speed detection device opposed to the rotational speed sensor via a predetermined axial clearance, the cover is disposed on the outer periphery of the inner side end of the outer member. A cylindrical fitting portion to be inserted, a flange portion extending radially inward from the fitting portion and being in close contact with an end surface of the outer member, and a bottom portion extending radially inward from the flange portion. In addition, an annular recess is formed in the outer diameter of the end of the inner ring, and the labyrinth seal is formed by engaging the cover with the annular recess.

  Thus, an annular cover press-fitted into the outer periphery of the inner side end of the outer member, and a sensor holder having a synthetic resin holding part that is coupled to the cover and has a rotational speed sensor embedded therein. An inner-side seal is fitted into the inner-side end of the outer member and is formed from a steel plate into a substantially L-shaped cross section by pressing, and a seal integrally joined to the core An annular seal plate made of a member and a slinger that is press-fitted into the outer diameter of the inner ring facing the seal plate and formed into a substantially L-shaped cross section by pressing from a steel plate, and on the inner side of the slinger A wheel shaft with a rotational speed detecting device, which is joined to the side surface by an encoder whose characteristics in the circumferential direction are alternately and equally spaced, and is opposed to the rotational speed sensor through a predetermined axial clearance. In the apparatus, the cover has a cylindrical fitting portion that is press-fitted into the outer periphery of the inner side end portion of the outer member, and extends radially inward from the fitting portion and is in close contact with the end surface of the outer member. And a bottom portion extending radially inward from the flange portion, an annular recess is formed in the outer diameter of the end of the inner ring, and a labyrinth seal is formed by engaging a cover with the annular recess. As a result, the seal can be completed with a single bearing without being affected by the accuracy of other components, such as coaxiality, and assembly accuracy, and the clearance of the labyrinth seal can be set optimally and accurately, and sufficient sealing performance can be obtained. Thus, it is possible to provide a wheel bearing device with a rotational speed detection device that can prevent foreign matters from directly entering the detection portion and improve reliability.

  According to a second aspect of the present invention, a cylindrical inner diameter portion extending in the axial direction from the bottom portion of the cover and a second bottom portion extending further inward in the radial direction from the inner diameter portion are formed. 2 and the wall surface of the annular recess of the inner ring face each other through a predetermined axial clearance, a labyrinth seal is formed, and the inner edge of the second bottom part and the outer periphery of the annular recess of the inner ring If the diameter is opposed to a predetermined radial clearance and a labyrinth seal is formed, the sealing performance can be improved.

  Preferably, as in the invention described in claim 3, if the inner diameter portion of the cover and the outer diameter of the inner ring face each other via a predetermined radial clearance and a labyrinth seal is formed, further sealing performance is achieved. And foreign matter can be prevented from entering the detection unit directly.

  According to a fourth aspect of the present invention, a deflector having a substantially L-shaped cross section is press-fitted into the outer diameter of the annular recess of the inner ring, and the deflector is press-fitted into the outer diameter of the annular recess. And a standing plate portion extending radially outward from the cylindrical portion, and the standing plate portion and the second bottom portion of the cover face each other through a predetermined axial clearance to form a labyrinth seal. As a result, it is possible to further improve the sealing performance and reliably prevent foreign matter from entering the detection unit directly.

  Further, as in the invention described in claim 5, a cylindrical inner diameter portion extending in the axial direction from the bottom portion of the cover is formed, and the outer diameter of the annular recess of the inner ring is substantially U-shaped in cross section. A seal ring is press-fitted, and a cylindrical fitting portion in which the seal ring is press-fitted into the outer diameter of the annular recess, a standing plate portion extending radially outward from the fitting portion, and the standing plate portion If the labyrinth seal is formed when the outer diameter portion and the inner diameter portion of the cover are opposed to each other through a predetermined radial clearance, The opposing range can be set large, and a sufficient labyrinth effect can be exhibited.

  Further, as in the invention described in claim 6, if a drain is formed at one place in the circumferential direction closest to the road surface at the bottom of the cover, foreign matters such as muddy water and pebbles are present in the bottom during traveling of the vehicle. Even if it enters, it is easily discharged and does not stay for a long time, so that it is possible to prevent foreign matter from adhering when the vehicle is stopped and adversely affecting peripheral parts.

  According to a seventh aspect of the present invention, the drain is formed by notching one circumferential portion of the bottom portion of the cover in a U-shape and raising the notch to the inner side. Then, the drain opens to the inner diameter side and the circumferential direction, and it is possible to further prevent foreign matters such as muddy water and pebbles from entering the cover while the vehicle is running.

  Further, as in the invention according to claim 8, if the drain is formed by forming a pair of slits in one circumferential direction of the bottom portion of the cover and cutting and raising this portion to the inner side, Since the drain opens only in the circumferential direction, it is possible to reliably prevent foreign matters such as muddy water and pebbles from entering the cover while the vehicle is running.

  If the cover is formed by press working from a non-magnetic steel plate having corrosion resistance as in the invention described in claim 9, the sensing performance of the rotation speed sensor is not adversely affected, and the cover It is possible to suppress rusting and maintain reliability over a long period of time.

  The wheel bearing device with a rotational speed detection device according to the present invention has an outer body integrally provided with a vehicle body mounting flange for being attached to a knuckle 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 An annular cover press-fitted to the outer periphery of the part, and this cover is connected to the rotational speed A sensor holder having a synthetic resin holding portion in which the sensor is embedded, and an inner seal of the seal is fitted into an inner end of the outer member, and is pressed from a steel plate by pressing. An annular seal plate made of a core metal having a substantially L-shaped cross section and a seal member integrally joined to the core metal, and press-fitted into the outer diameter of the inner ring facing the seal plate, A slinger having a substantially L-shaped cross section formed by press working is joined to an inner side surface of the slinger, and an encoder whose characteristics in the circumferential direction change alternately and at equal intervals is joined to the encoder. In the wheel bearing device with a rotational speed detection device opposed to the speed sensor via a predetermined axial clearance, the cover is press-fitted into the outer periphery of the inner side end of the outer member. A cylindrical fitting portion, a flange portion extending radially inward from the fitting portion, being in close contact with the end surface of the outer member, and a bottom portion extending radially inward from the flange portion. An annular recess is formed on the outer diameter of the end of the inner ring, and the cover is engaged with the annular recess to form a labyrinth seal. The seal is completed with the bearing alone, and the clearance of the labyrinth seal can be set optimally and accurately, so that sufficient sealing performance can be obtained, and foreign matter can be prevented from entering the detector directly. It is possible to provide a wheel bearing device with a rotational speed detection device with improved reliability.

  A vehicle body mounting flange to be attached to the knuckle on the outer periphery, an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a wheel mounting flange to mount a wheel on one end A hub wheel integrally formed and formed on the outer periphery with an inner rolling surface facing one of the double row outer rolling surfaces, and a cylindrical small-diameter stepped portion extending in the axial direction from the inner rolling surface; and An inner member comprising an inner ring press-fitted into the small-diameter step portion of the hub wheel and having an inner rolling surface facing the other of the outer rolling surfaces of the double row on the outer periphery, and the inner member and the outer member A double-row rolling element accommodated between both rolling surfaces of the member, and a seal attached to an opening of an annular space formed between the outer member and the inner member; An annular cover press-fitted into the outer periphery of the inner side end of the outer member and coupled to this cover And a sensor holder having a synthetic resin holding portion in which a rotation speed sensor is embedded, and an inner seal of the seal is fitted into an inner end of the outer member, and a steel plate And press-fit into the outer diameter of the inner ring facing the seal plate, and an annular seal plate formed of a core member formed into a substantially L-shaped cross section by pressing and a seal member integrally joined to the core metal The slinger is formed from a steel plate by press working to have a substantially L-shaped cross section, and magnetic powder is mixed in the elastomer on the inner side surface of the slinger so that the magnetic poles N and S are alternately arranged in the circumferential direction. In a wheel bearing device with a rotational speed detection device in which a magnetized magnetic encoder is joined, and the magnetic encoder is opposed to the rotational speed sensor via a predetermined axial clearance, the cover includes: A cylindrical fitting portion that is press-fitted into the outer periphery of the inner side end portion of the outer member, a flange portion that extends radially inward from the fitting portion and is in close contact with the end surface of the outer member, A bottom portion extending radially inward from the flange portion, a cylindrical inner diameter portion extending axially from the bottom portion, and a second bottom portion extending further radially inward from the inner diameter portion are formed. And the wall surface of the annular recess of the inner ring face each other through a predetermined axial clearance, a labyrinth seal is formed, and the inner edge of the second bottom portion and the outer diameter of the annular recess of the inner ring are A labyrinth seal is formed through a predetermined radial clearance.

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 showing a detection unit of FIG. 1, and FIG. FIG. 4 is an enlarged view of a main part showing another modification example of FIG. 2, FIG. 5 is an enlarged view of a main part showing a modification example of FIG. 3, and FIG. The principal part enlarged view which shows another modification, Fig.7 (a) is a principal part enlarged view which shows the cover which concerns on this invention, (b) is sectional drawing along the VII-VII line of (a), figure 8 (a) is an enlarged view of a main part showing a modification of FIG. 7, (b) is a sectional view taken along line VIII-VIII of (a), and FIG. 9 (a) is another modification of FIG. The principal part enlarged view which shows an example, (b) is sectional drawing along the IX-IX line of (a). In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side in FIG. 1), and the side closer to the center is referred to as the inner side (right side in FIG. 1).

  This wheel bearing device with a rotational speed detection device is called a third generation for driving wheels, and includes an inner member 3 composed of a hub wheel 1 and an inner ring 2, and double row rolling elements (balls) on the inner member 3. 4 and 4 and an outer member 5 inserted through 4 and 4, and a constant velocity universal joint (not shown) is connected to the hub wheel 1 so as to transmit torque.

  The hub wheel 1 integrally has a wheel mounting flange 6 for attaching a wheel (not shown) to an end portion on the outer side, and hub bolts 6 a are implanted at circumferentially equidistant positions of the wheel mounting flange 6. Yes. Further, an outer side (one) 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 on the outer periphery, and a torque transmission serration ( Or a spline) 1c is formed. An inner ring 2 is press-fitted and fixed to the small-diameter step portion 1b of the hub wheel 1 through a predetermined shimiro, and an inner side (other side) inner rolling surface 2a is formed on the outer periphery of the inner ring 2.

  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 an inner rolling surface 1a and an inner side of a wheel mounting flange 6 serving as a seal land portion of a seal 8 described later. The surface is hardened in the range of 50 to 64 HRC by induction hardening from the base 6b to the small diameter step 1b. As a result, not only the wear resistance of the base portion 6b is improved, but also the fretting of the small-diameter step portion 1b serving as the fitting surface of the inner ring 2 is suppressed, and the rotational bending load applied to the wheel mounting flange 6 is suppressed. And sufficient mechanical strength, and the durability of the hub wheel 1 is improved. The inner ring 2 and the rolling element 4 are made of a high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC up to the core by quenching.

  The outer member 5 is made of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and integrally has a vehicle body mounting flange 5b for attaching to a knuckle (not shown) on the outer periphery. Double row outer rolling surfaces 5a, 5a facing the double row inner rolling surfaces 1a, 2a of the inner member 3 are integrally formed. These double-row outer raceway surfaces 5a and 5a are subjected to a hardening process in a range of 50 to 64 HRC by induction hardening. Between the double-row outer rolling surfaces 5a and 5a of the outer member 5 and the double-row inner rolling surfaces 1a and 2a of the inner member 3 opposed thereto, double-row rolling elements 4 and 4 are respectively provided. It is accommodated and held by the cages 7 and 7 so as to be able to roll. In addition, seals 8 and 9 are attached to the opening of the annular space formed between the outer member 5 and the inner member 3, and leakage of lubricating grease sealed inside the bearing and the inside of the bearing from the outside. Prevents intrusion of rainwater and dust.

  Here, the wheel bearing device constituted by a double row angular contact ball bearing in which the rolling element 4 is a ball is illustrated, but the present invention is not limited to this, and a double row tapered roller bearing using a tapered roller for the rolling element 4 is used. May be. In addition, the third generation structure in which the inner raceway surface 1a is formed directly on the outer periphery of the hub wheel 1 is illustrated. However, the present invention is not limited to this, and the second generation in which a pair of inner rings are press-fitted and fixed to the small diameter step portion of the hub wheel. It may be a structure.

  The outer-side seal 8 is constituted by an integral seal comprising a cored bar 10 and a seal member 11 integrally joined to the cored bar 10 by vulcanization adhesion. The core metal 10 is formed by pressing a cold rolled steel plate (JIS standard SPCC system or the like). The seal member 11 is made of synthetic rubber such as nitrile rubber and is integrally joined to the cored bar 10 by vulcanization adhesion. The seal member 11 includes a side lip 11a formed to be inclined outward in the radial direction, a dust lip 11b and a grease lip 11c formed in a bifurcated shape. The base portion 6b of the wheel mounting flange 6 is formed in an arcuate curved surface, the side lip 11a is in sliding contact with the base portion 6b with a predetermined axial direction, and the dust lip 11b and the grease lip 11c are predetermined. It is in sliding contact with the radial direction.

  As shown in an enlarged view in FIG. 2, the inner-side seal 9 is disposed opposite to each other, and an annular seal plate 12 mounted in an opening of an annular space formed between the outer member 5 and the inner ring 2. And a slinger 13, which is a so-called pack seal. The seal plate 12 includes a cored bar 14 fitted into the inner side end of the outer member 5 and a seal member 15 integrally joined to the cored bar 14 by vulcanization adhesion. The core 14 is pressed from an austenitic stainless steel plate (JIS standard SUS304, etc.), a ferritic stainless steel plate (JIS standard SUS430, etc.), or a cold rolled steel plate (JIS standard SPCC, etc.). The cross section is formed in a substantially L shape. On the other hand, the seal member 15 is made of synthetic rubber such as nitrile rubber, and includes a side lip 15a formed to be inclined outward in the radial direction, a grease lip 15b and an intermediate lip 15c formed in a bifurcated shape.

  The slinger 13 includes a cylindrical portion 13a that is press-fitted into the inner ring 2 and a standing plate portion 13b that extends radially outward from the cylindrical portion 13a, and is made of a ferromagnetic steel plate, for example, ferritic stainless steel. It is formed into a substantially L-shaped cross section by pressing from a steel plate (JIS standard SUS430 series or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC system or the like). The side lip 15a of the seal member 15 is in sliding contact with the upright plate portion 13b, and the grease lip 15b and the intermediate lip 15c are in sliding contact with the cylindrical portion 13a. The outer edge of the standing plate portion 13b of the slinger 13 is opposed to the seal plate 12 through a slight radial clearance to form a labyrinth seal.

  A magnetic encoder 16 in which magnetic powder such as ferrite is mixed in an elastomer such as synthetic rubber is integrally joined to the inner side surface of the standing plate portion 13b of the slinger 13 by vulcanization adhesion or the like. This magnetic encoder 16 is magnetized with magnetic poles N and S alternately at equal intervals in the circumferential direction, and constitutes a rotary encoder for detecting the rotational speed of the wheel.

  In the present embodiment, a cover 17 is fitted on the inner end of the outer member 5, and a sensor holder 18 is fixed to the cover 17. The sensor holder 18 includes a holding unit 20 in which the rotation speed sensor 19 is embedded, and a take-out port 20a extending from the holding unit 20 outward in the radial direction. The cover 17 is a cylindrical fitting portion 17a that is press-fitted to the outer periphery of the inner side end of the outer member 5, and extends radially inward from the fitting portion 17a, and is in close contact with the end surface 5c of the outer member 5. A flange portion 17b, a bottom portion 17c extending radially inward from the flange portion 17b, a cylindrical inner diameter portion 17d extending in the axial direction from the bottom portion 17c, and a first inner portion extending further radially inward from the inner diameter portion 17d. 2 bottom portions 17e and formed in an annular shape as a whole.

  In this manner, the fitting portion 17a is fitted on the inner side end of the outer member 5 with the flange portion 17b in close contact with the end surface 5c of the outer member 5, so that the outer member 5 On the other hand, the sensor holder 18 can be positioned and fixed easily and accurately, and the rotational speed of the wheel can be detected with high accuracy. The cover 17 is formed by pressing a non-magnetic steel plate having corrosion resistance, for example, a stainless steel plate such as an austenitic stainless steel plate (JIS standard SUS304 type or the like). Thus, there is provided a wheel bearing device with a rotation speed detection device that does not adversely affect the sensing performance of the rotation speed sensor 19 and also prevents rusting of the cover 17 and maintains reliability over a long period of time. Can do.

  The holding unit 20 is formed by injection molding from a non-magnetic special ether-based synthetic resin material such as polyphenylene sulfide (PPS), and further a reinforcing material such as GF (glass fiber) is added. The rotational speed sensor 19 embedded in the holding unit 20 is opposed to the magnetic encoder 16 via a predetermined axial clearance (air gap). As a result, the sensing performance of the rotation speed sensor 19 is not adversely affected, the corrosion resistance is excellent, and the strength and durability can be improved over a long period of time.

  The rotational speed sensor 19 incorporates a magnetic detecting element such as a Hall element, a magnetoresistive element (MR element), etc. that changes its characteristics according to the flow direction of magnetic flux, and a waveform shaping circuit that adjusts the output waveform of the magnetic detecting element. It consists of an IC element. Thereby, it is possible to detect the rotational speed with high reliability at low cost. In addition to the materials described above, the holding portion 20 can be exemplified by synthetic resins that can be injection molded such as PA (polyamide) 66, PPA (polyphthalamide), PBT (polybutylene terephthalate), and the like.

  Here, as an example of the rotational speed detection device, an active type rotational speed detection device including a magnetic encoder 16 and a rotational speed sensor 19 including a magnetic detection element such as a Hall element is illustrated, but the rotational speed detection device according to the present invention is illustrated. The apparatus is not limited to this, and may be a passive type including, for example, a gear, a magnet, and an annular coil wound.

  Here, an annular recess 21 is formed in the outer diameter of the end portion of the inner ring 2, and a plurality of labyrinth seals S <b> 1 and S <b> 2 are formed by engaging the second bottom portion 17 e of the cover 17 with the annular recess 21. . That is, the wall surface 21a of the annular recess 21 and the second bottom portion 17e face each other through a predetermined axial clearance, and the outer diameter 21b of the annular recess 21 and the inner edge of the second bottom portion 17e have a predetermined diameter. Two labyrinth seals S1 and S2 are formed to face each other through the directional clearance. As described above, since the plurality of labyrinth seals S1 and S2 are formed between the cover 17 and the inner ring 2, the seal is completed by the bearing alone without being affected by the accuracy of the other components such as the coaxial and the assembly accuracy. The labyrinth seals S1 and S2 can be set optimally and with high accuracy, and sufficient sealing performance can be obtained. Rotation with improved reliability by preventing foreign matter from entering the detector directly. A wheel bearing device with a speed detection device can be provided.

  FIG. 3 shows a modification. Note that this embodiment basically differs from the above-described embodiment (FIG. 2) only in part in the configuration of the cover, and other parts or parts having the same parts or parts having the same functions are denoted by the same reference numerals. Thus, duplicate explanations are omitted.

  The cover 22 is press-fitted into the outer periphery of the inner side end of the outer member 5, and extends radially inward from the fitting portion 17 a, and is in close contact with the end surface 5 c of the outer member 5. A flange portion 17b, a bottom portion 17c extending radially inward from the flange portion 17b, a cylindrical inner diameter portion 22a extending in the axial direction from the bottom portion 17c, and a first inner portion extending further radially inward from the inner diameter portion 22a. 2 bottom portions 17e and formed in an annular shape as a whole. This cover 22 is formed by pressing a non-magnetic steel plate having corrosion resistance, for example, a stainless steel plate such as an austenitic stainless steel plate (JIS standard SUS304 type or the like). While suppressing rusting, the sensing performance of the rotation speed sensor 19 is not adversely affected.

  Here, the wall surface 21a and the second bottom portion 17e of the annular recess 21 of the inner ring 2 and the outer diameter 21b of the annular recess 21 and the inner edge of the second bottom portion 17e face each other through a predetermined gap, and two Labyrinth seals S1 and S2 are formed. Further, the outer diameter 2b of the inner ring 2 and the inner diameter portion 22a of the cover 22 face each other through a predetermined radial clearance to form a labyrinth seal S3. As described above, since the three labyrinth seals S1, S2, and S3 are formed between the cover 22 and the inner ring 2, the sealing performance can be further improved, and it is ensured that foreign matter enters the detection unit directly. Can be prevented.

  FIG. 4 shows another modification. Note that this embodiment basically differs from the above-described embodiment only in the configuration of a part of the cover and the inner ring, and other parts and parts having the same parts or parts having the same functions are denoted by the same reference numerals. A duplicate description is omitted.

  The cover 23 is press-fitted into the outer periphery of the inner side end portion of the outer member 5, and extends radially inward from the fitting portion 17 a, and is in close contact with the end surface 5 c of the outer member 5. And a bottom portion 23a extending radially inward from the flange portion 17b, and is formed in an annular shape as a whole. The cover 23 is formed by pressing a non-magnetic steel plate having corrosion resistance, for example, a stainless steel plate such as an austenitic stainless steel plate (JIS standard SUS304 type or the like). While suppressing rusting, the sensing performance of the rotation speed sensor 19 is not adversely affected. On the other hand, an annular recess 21 ′ is formed on the outer diameter of the end of the inner ring 2 ′, and the wall surface 21a ′ and the bottom 23a of the annular recess 21 ′, the outer diameter 21b of the annular recess 21 ′, and the inner edge of the bottom 23a, respectively. Two labyrinth seals S1 and S2 are formed facing each other through a predetermined gap. As a result, the sealing performance can be improved, and the shape of the cover 23 is simplified, and the clearance between the labyrinth seals S1 and S2 can be set optimally and accurately while achieving compactness.

  FIG. 5 shows another modification. In this embodiment, only a deflector is added to the above-described embodiment (FIG. 3), and the same parts and parts having the same functions or parts having the same functions are denoted by the same reference numerals and redundant description is omitted. To do.

  A wall surface 21a and a second bottom portion 17e of the annular recess 21 of the inner ring 2, an outer diameter 21b and an inner edge of the second bottom portion 17e of the annular recess 21, and an outer diameter 2b of the inner ring 2 and an inner diameter portion 22a of the cover 22 are provided. Three labyrinth seals S1, S2, and S3 are formed to face each other through a predetermined gap. A deflector 24 is press-fitted into the outer diameter 21 b of the annular recess 21, and is arranged in parallel with the cover 22. This deflector 24 is pressed from an austenitic stainless steel plate (JIS standard SUS304 type, etc.), a ferritic stainless steel plate (JIS standard SUS430 type, etc.), or a cold rolled steel plate (JIS standard SPCC type, etc.). Are formed in a substantially L-shaped cross section, and include a cylindrical portion 24a that is press-fitted into the outer diameter 21b of the annular recess 21 and a standing plate portion 24b that extends radially outward from the cylindrical portion 24a. Here, the standing plate portion 24b of the deflector 24 faces the second bottom portion 17e of the cover 22 via a predetermined axial clearance, and a labyrinth seal S4 is formed.

  Thus, three labyrinth seals S 1, S 2, S 3 are formed between the cover 22 and the inner ring 2, and the deflector 24 is press-fitted into the annular recess 21 of the inner ring 2. Since the labyrinth seal S4 is formed between them, the sealing performance can be further improved, and it is possible to reliably prevent foreign matter from entering the detection portion directly.

  FIG. 6 shows still another modification. It should be noted that the same parts and parts as those in the above-described embodiment or parts and parts having the same functions are denoted by the same reference numerals, and redundant description is omitted.

  An annular recess 21 ″ is formed in the outer diameter of the end of the inner ring 2 ″. The annular recess 21 ″ includes an inclined wall surface 21a ″ and a cylindrical outer diameter 21b, and a seal ring 25 is press-fitted into the outer diameter 21b. The seal ring 25 is pressed from an austenitic stainless steel plate (JIS standard SUS304, etc.), a ferritic stainless steel plate (JIS standard SUS430, etc.), or a cold rolled steel plate (JIS standard SPCC, etc.). And a cylindrical fitting portion 25a that is press-fitted into the outer diameter 21b of the annular recess 21 ″ and a standing plate portion 25b that extends radially outward from the fitting portion 25a. And a cylindrical outer diameter portion 25c extending in the axial direction from the standing plate portion 25b.

  On the other hand, the cover 26 is a cylindrical fitting portion that is press-fitted into the outer periphery of the inner side end of the outer member (not shown), and extends radially inward from the fitting portion, and is in close contact with the end surface of the outer member. The flange portion, a bottom portion 17c extending radially inward from the flange portion, and a cylindrical inner diameter portion 17d extending in the axial direction from the bottom portion 17c are formed in an annular shape as a whole. The inner diameter portion 17d and the outer diameter portion 25c of the seal ring 25 are opposed to each other through a predetermined radial clearance, thereby forming a labyrinth seal S5. Thus, the annular recess 21 ″ is formed at the outer diameter end portion of the inner ring 2 ″, the seal ring 25 is press-fitted into the outer diameter 21b of the annular recess 21 ″, and the outer diameter portion 25c of the seal ring 25 is also pressed. Since the labyrinth seal S5 is formed between the cover 26 and the cover 26, the facing range of both members can be set large, and a sufficient labyrinth effect can be exhibited.

  Further, in the present embodiment, as shown in FIG. 7, an eyebrow-shaped drain 27 is formed at one place in the circumferential direction closest to the road surface at the bottom 17 c of the cover 26. Even if foreign matter such as muddy water or pebbles enters the bottom portion 17c while the vehicle is running, the drain 27 is easily discharged and does not stay for a long time. It is possible to prevent adverse effects on parts. Note that the drain 27 is not limited to the bottom portion 17c of the cover 26, and may be formed between the bottom portion 17c and the flange portion 17b. Also good.

  FIG. 8 is a modification of the drain 27 of FIG. The cover 28 has a cylindrical fitting portion 17 a that is press-fitted into the outer periphery of the inner side end of the outer member 5, extends radially inward from the fitting portion 17 a, and is attached to the end surface 5 c of the outer member 5. The flange portion 17b is in close contact, the bottom portion 28a extends radially inward from the flange portion 17b, and the cylindrical inner diameter portion 17d extends axially from the bottom portion 28a, and is formed in an annular shape as a whole. The drain 29 is formed by partially raising the bottom portion 28 a of the cover 28. That is, one portion in the circumferential direction of the bottom portion 28a is cut out in a U shape, and the cutout portion 29a is plastically deformed toward the inner side. As a result, the drain 29 opens toward the inner diameter portion 17d and in the circumferential direction, and it is possible to further prevent foreign matter such as muddy water and pebbles from entering the cover 28 while the vehicle is running.

  FIG. 9 shows another modification of the drain 27 of FIG. The cover 30 has a cylindrical fitting portion 17a that is press-fitted into the outer periphery of the inner side end of the outer member 5, and extends radially inward from the fitting portion 17a, and is attached to the end surface 5c of the outer member 5. The flange portion 17b is in close contact, the bottom portion 30a extends radially inward from the flange portion 17b, and the cylindrical inner diameter portion 17d extends in the axial direction from the bottom portion 30a, and is formed in an annular shape as a whole. The drain 31 is formed by partially raising the bottom 30 a of the cover 30. That is, a pair of slits 31a is formed at one place in the circumferential direction of the bottom 30a, and this portion is formed by plastic deformation on the inner side. As a result, the drain 31 is opened only in the circumferential direction, and foreign matter such as muddy water and pebbles can be reliably prevented from entering the cover 30 during traveling of the vehicle.

  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 of a second or third generation structure in which any type of rotation speed detection device is built in the inner ring rotation structure.

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 which shows the detection part of FIG. It is a principal part enlarged view which shows the modification of FIG. It is a principal part enlarged view which shows the other modification of FIG. It is a principal part enlarged view which shows the modification of FIG. It is a principal part enlarged view which shows the other modification of FIG. (A) is a principal part enlarged view which shows the cover which concerns on this invention. (B) is sectional drawing which followed the VII-VII line of (a). (A) is a principal part enlarged view which shows the modification of FIG. (B) is sectional drawing which followed the VIII-VIII line of (a). (A) is a principal part enlarged view which shows the other modification of FIG. (B) is sectional drawing along the IX-IX line of (a). It is a principal part enlarged view which shows the conventional wheel bearing apparatus with a rotational speed detection apparatus.

Explanation of symbols

1 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheel 1a, 2a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 1b ・···················· Small diameter step 1c ......... Serrations 2, 2 ', 2 "... Inner ring 2b ... Outer diameter of inner ring 3 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner member 4 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rolling element 5 ・ ・ ・ ・ ・ ・· · · · · · · · Outer member 5a · · · · · outer rolling surface 5b ...・ ・ ・ ・ ・ ・ ・ ・ Car body mounting flange 5c ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ End face 6 of outer member ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... ..... Wheel mounting flange 6a ..... Hub bolt 6b ...・ ・ ・ ・ ・ Base 7 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Retainer 8 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Outer side seal 9 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner side seal 10, 14 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Cores 11 and 15 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal members 11a and 15a ・ ・ ・ ・ ・ ・ Side lip 11b・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Dustrip 11c, 15b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Grease Lip 12 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・..... Seal plate 13 ... ... Slinger 13a, 24a ... Cylindrical part 13b, 24b, 25b ... Standing plate part 15c ... Intermediate lip 16 ... Magnetic encoder 17, 22, 23, 26, 28, 30 .. Cover 17a, 25a ..... Fitting part 17b ............. 17c, 23a, 28a, 30a ......... bottom part 17d, 22a ......... inner diameter part 17e ... 2nd bottom 18 ... Sensor holder 19 ... ... Rotational speed sensor 20 ... ············ Holding part 20a ................................................................ annular recesses 21a, 21a ', 21a "......... wall surface 21b of the annular recess ... Annular recess outer diameter 24 ... Deflector 25 ... Seal Ring 25c ......... Outer diameter parts 27, 29, 31 ... Drain 29a ...・ ・ ・ ・ ・ ・ ・ ・ ・ Notch 31a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Slit 50・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 51 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Enko 52 ... Outer member 53 ... Sensor holder 54・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rotational speed sensor 55 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cover 55a ···················· Fitting portion 55b・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Bottom 56 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal 57 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Slinger 57a ... Cylindrical part 57b ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal plate 59 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Core 60 ... Sealing member 60a ... Side lip 60b ... Grease lip 60c ... Intermediate lip 61 ... ... holding part 62 ... harness 63 ... Extraction port 64 Outer joint member 65 ... .... Round hole 66 ..... Shoulder 67 ... S1, S2, S3, S4, S5 ... Labyrinth seals α, β ... ............ inclination angle

Claims (9)

An outer member integrally having a vehicle body mounting flange for being attached to the knuckle 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;
An annular cover press-fitted into the outer periphery of the inner side end of the outer member, and a sensor holder having a synthetic resin holding part that is coupled to the cover and in which a rotation speed sensor is embedded;
Of the seals, an inner side seal is fitted into an inner side end of the outer member, and is formed by pressing a steel plate into a substantially L-shaped cross section, and integrally joined to the core. An annular seal plate made of a sealed member, and a slinger that is press-fitted into the outer diameter of the inner ring so as to face the seal plate and is formed into a substantially L-shaped cross section by pressing from a steel plate. A wheel with a rotational speed detection device in which an encoder whose characteristics in the circumferential direction change alternately and at equal intervals is joined to the side surface on the inner side of the motor, and the encoder faces the rotational speed sensor via a predetermined axial clearance. Bearing device for
The cover has a cylindrical fitting portion that is press-fitted into the outer periphery of the inner side end portion of the outer member, and extends radially inward from the fitting portion and is in close contact with the end surface of the outer member. And a bottom portion extending radially inward from the flange portion, and an annular recess is formed in the outer diameter of the end of the inner ring, and the cover engages with the annular recess to form a labyrinth seal. A wheel bearing device with a rotational speed detection device, characterized in that   A cylindrical inner diameter portion extending in the axial direction from the bottom portion of the cover and a second bottom portion extending further radially inward from the inner diameter portion are formed. The second bottom portion and the wall surface of the annular recess of the inner ring And a labyrinth seal are formed, and an inner edge of the second bottom portion and an outer diameter of the annular recess of the inner ring are opposed via a predetermined radial clearance. The wheel bearing device with a rotational speed detection device according to claim 1, wherein a labyrinth seal is formed.   The wheel bearing device with a rotation speed detection device according to claim 2, wherein a labyrinth seal is formed by an inner diameter portion of the cover and an outer diameter of the inner ring facing each other through a predetermined radial clearance.   A deflector having a substantially L-shaped cross section is press-fitted into the outer diameter of the annular recess of the inner ring, and the deflector extends in a radially outward direction from the cylindrical part that is press-fitted into the outer diameter of the annular recess. The rotation speed detection according to claim 2 or 3, comprising a vertical plate portion, wherein the vertical plate portion and the second bottom portion of the cover are opposed to each other via a predetermined axial clearance to form a labyrinth seal. Wheel bearing device with device.   A cylindrical inner diameter portion extending in the axial direction from the bottom of the cover is formed, and a substantially U-shaped seal ring is press-fitted into the outer diameter of the annular recess of the inner ring. From a cylindrical fitting portion press-fitted into the outer diameter of the recess, a standing plate portion extending radially outward from the fitting portion, and a cylindrical outer diameter portion extending axially from the standing plate portion The wheel bearing device with a rotation speed detecting device according to claim 1, wherein the outer diameter portion and the inner diameter portion of the cover are opposed to each other through a predetermined radial clearance to form a labyrinth seal.   The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 5, wherein a drain is formed at one place in a circumferential direction closest to the road surface at the bottom of the cover.   The wheel with a rotation speed detecting device according to claim 6, wherein the drain is formed by cutting out one circumferential portion of the bottom portion of the cover in a U-shape and raising the notched portion toward the inner side. Bearing device.   7. The wheel bearing device with a rotational speed detection device according to claim 6, wherein the drain is formed by forming a pair of slits at one circumferential position on the bottom of the cover and cutting the portion toward the inner side. .   The wheel bearing device with a rotation speed detecting device according to any one of claims 1 to 8, wherein the cover is formed by press working from a non-magnetic steel plate having corrosion resistance.

Images