JP2009149121A - Wheel bearing device with rotation speed detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing device having a rotation speed detection device in which productivity is improved, cost reduction is attained and assembling workability is improved. <P>SOLUTION: The wheel bearing device is provided with: a pulsar ring 11 outwardly fitted to an inner ring 7; a cover 10 installed at the end part of an outer member 4 and having an insertion hole 27 at a position opposing against the pulsar ring 11; and a sensor holder 20 inserted into the insertion hole 27 and having an insertion part 21a enclosed by a rotation speed sensor 19 and a fixing flange 20b fixed to the cover 10. The insertion hole 27 is constituted by a tapered part 27a showing a predetermined slant angle &alpha; and a cylindrical part 27b extending from a substantial axial central part of the tapered part 27a in a straight manner. An inner diameter &phiv;F at a small diameter part of the tapered part 27a is set to be slightly larger than an outer diameter &phiv;C of the insertion part 21a and the outer periphery of the insertion part 21a is formed with an annular groove 22. An O-ring 28 resiliently contacted with the cylindrical part 27b of the insertion hole 27 is installed in the annular groove 22. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention incorporates a wheel bearing device for rotatably supporting a wheel of an automobile or the like with respect to a suspension device, in particular, a rotation speed detection device for detecting the rotation speed of the wheel, thereby improving productivity and reducing cost. The present invention relates to a wheel bearing device with a rotation speed detection device that is intended to improve assembly workability.

  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.

  Generally, 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, a wheel bearing with a rotational speed detection device that has a rotational speed sensor built into the bearing has recently been developed. A device has been proposed.

  A structure as shown in FIG. 5 is known as an example of such a wheel bearing device with a rotational speed detection device. This wheel bearing device with a rotational speed detection device is supported and fixed to a knuckle (not shown), and is inserted into the outer member 51 serving as a fixing member and the outer member 51 via double rows of balls 53 and 53. And an inner member 52. The inner member 52 includes a hub ring 55 and an inner ring 56 that is externally fitted to the hub ring 55.

  The outer member 51 integrally has a vehicle body mounting flange 51b on the outer periphery, and double row outer rolling surfaces 51a and 51a are formed on the inner periphery. On the other hand, the inner member 52 is formed with double-row inner rolling surfaces 55a and 56a facing the outer rolling surfaces 51a and 51a of the outer member 51 described above. Of the double row inner rolling surfaces 55 a and 56 a, one inner rolling surface 55 a is integrally formed on the outer periphery of the hub wheel 55, and the other inner rolling surface 56 a is formed on the outer periphery of the inner ring 56. The inner ring 56 is press-fitted into a shaft-shaped small-diameter step portion 55 b that extends in the axial direction from the inner rolling surface 55 a of the hub wheel 55. The double-row balls 53 and 53 are respectively accommodated between the rolling surfaces and are held by the cages 57 and 57 so as to be freely rollable.

  The hub wheel 55 integrally has a wheel mounting flange 54 for mounting a wheel (not shown) on the outer periphery, and a crimped portion 58 is formed by plastically deforming the end portion of the small diameter step portion 55b radially outward. The inner ring 56 is fixed in the axial direction by the caulking portion 58. A seal 59 and a cover 63 are attached to the end of the outer member 51 to prevent leakage of lubricating grease sealed inside the bearing and intrusion of rainwater, dust, or the like from the outside into the bearing. .

  A magnetic encoder 60 is press-fitted into the outer periphery of the inner ring 56. The magnetic encoder 60 includes a support ring 61 that is formed in a ring shape having a substantially T-shaped cross section by a magnetic metal plate, and an encoder body 62 that is attached to a side surface of the support ring 61. The encoder body 62 is made of a permanent magnet such as rubber mixed with ferrite powder, and S poles and N poles are alternately magnetized at equal intervals in the circumferential direction.

  The cover 63 is externally fitted and fixed to the opening end of the outer member 51 on the inboard side, and closes the opening of the outer member 51. The cover 63 includes a bottomed cylindrical cover body 64 formed by injection molding synthetic resin, and a fitting cylinder 65 coupled to an opening of the cover body 64. The fitting cylinder 65 is formed in an annular shape having an L-shaped cross section by press forming a stainless steel plate having corrosion resistance. The cover body 64 is integrated with the cover body 64 by molding at the time of injection molding.

  A protrusion 66 protruding in the axial direction is formed on the radially outer portion of the cover body 64, and an insertion hole 67 is formed in the protrusion 66 at a position corresponding to the magnetic encoder 60. The sensor unit 68 is inserted into the insertion hole 67. This sensor unit 68 incorporates a sensor composed of a magnetic detection element whose characteristics change according to the flow direction of the magnetic flux, such as a Hall element, a magnetoresistive element (MR element), and a waveform shaping circuit for adjusting the output waveform of the magnetic detection element. The automobile ABS is configured to detect the rotational speed of the wheel and control the rotational speed.

  The sensor is embedded in a holder 69 made of synthetic resin. As shown in FIG. 6, the holder 69 is formed with an insertion portion 69 a and a mounting flange 69 b, and an annular groove 70 is formed on the outer periphery of the intermediate portion of the insertion portion 69 a, and an O-ring 71 is formed in the annular groove 70. Is installed. A connector 72 is directly fixed to a part of the sensor unit 68, and a protrusion 73 is formed on the side opposite to the insertion portion 69a. Then, the connector 72 is embedded and supported by the protrusion 73 in a state where the connection direction thereof coincides with the axial position of the sensor unit 68. A nut 74 is embedded in the end surface of the protrusion 66 of the cover 63, and the sensor unit 68 is coupled and fixed to the nut 74 via a bolt 75.

According to the conventional wheel bearing device with a rotational speed detection device configured as described above, even when the sensor unit 68 is mounted on the cover 63 and transported or assembled to the vehicle body, a long harness is provided from the sensor unit 68. Is not led out to the outside, and the efficiency of the transfer work and the assembly work can be improved.
JP 2001-349899 A

  In such a conventional wheel bearing device with a rotational speed detection device, the cover body 64 and the sensor unit 68 are formed by injection molding synthetic resin, so there is a limit to increasing the shape and dimensional accuracy. A backlash occurs between the hole 67 and the sensor unit 68. Further, if the size of the insertion hole 67 is set to a small diameter in order to close the backlash, not only the insertion property of the sensor unit 68 is deteriorated, but also the O-ring 71 is attached in a twisted state. There is a risk that the seal will be significantly reduced due to non-uniformity.

  Further, such a cover body 64 and sensor unit 68 are normally sealed without severely restricting play between the insertion hole 67 and the insertion portion 69a of the sensor unit 68 due to variations in shape and dimensions during molding or misalignment. It has been a challenge to improve the assembly workability.

  The present invention has been made in view of such a conventional problem, and provides a wheel bearing device with a rotational speed detection device that improves productivity and reduces costs and improves assembly workability. For the purpose.

  In order to achieve such an object, the invention according to claim 1 of the present invention includes an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a wheel for attaching a wheel to one end. A hub ring integrally having a mounting flange and formed with 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 of inner rolling surfaces facing the outer rolling surface is formed, and a double row of rolling members housed between the outer member and the inner member so as to roll freely. A moving body, a pulsar ring that is externally fitted to the inner ring, and whose characteristics are alternately changed at equal intervals in the circumferential direction, and an internal fitting fixed to the opening end on the inner side of the outer member, are injected with synthetic resin. A cylindrical cover with a bottom that is formed and has an insertion hole at a position facing the pulsar ring. A main body, a cover made of a core metal integrally molded in the opening of the cover main body, a cylindrical insertion portion inserted into the insertion hole and embedded with a rotation speed sensor, and fixed to the cover main body And a sensor holder having a mounting flange, wherein the sensor holder is detachably fixed to the cover body via a fixing bolt. It is formed in a tapered shape that gradually becomes smaller in diameter toward the side, and is slightly larger than the outer diameter of the insertion portion of the sensor holder.

  In this way, the pulsar ring in which the hub wheel and the double row rolling bearing are unitized and externally fitted to the inner ring constituting the double row rolling bearing, and the characteristics are alternately changed at equal intervals in the circumferential direction. And a bottomed cylindrical cover body that is fitted and fixed to the opening end on the inner side of the outer member, is injection-molded with synthetic resin, and has an insertion hole at a position facing the pulsar ring, and the cover body A cover made of a core metal integrally molded in the opening; a cylindrical insertion part that is inserted into the insertion hole and in which the rotation speed sensor is embedded; and a sensor holder having a mounting flange that is fixed to the cover body. In the wheel bearing device with a rotation speed detection device in which the sensor holder is detachably fixed to the cover body via a fixing bolt, the insertion hole of the cover body gradually decreases in diameter toward the inner side of the bearing. Since the outer diameter of the insertion part of the sensor holder is slightly larger than the outer diameter of the sensor holder, the radial clearance between the inner diameter of the smaller diameter part and the outer diameter of the insertion part of the sensor holder is cylindrical. The inner diameter of the large-diameter portion of the insertion hole can be made larger than that of the conventional inner diameter even if it is about the same as the conventional radial clearance formed on the sensor. Workability can be improved. Moreover, since the insertion hole is formed in a taper shape, a draft angle at the time of injection molding can be secured, and productivity can be increased and cost can be reduced.

  Preferably, as in the second aspect of the invention, the insertion hole includes a tapered portion having a predetermined inclination angle and a cylindrical portion extending straight from the substantially central portion in the axial direction of the tapered portion to the inner side. And the inner diameter of the small diameter portion of the tapered portion is set to be slightly larger than the outer diameter of the insertion portion of the sensor holder, and an annular groove is formed on the outer periphery of the insertion portion. If the O-ring that comes into elastic contact with the cylindrical portion of the insertion hole is attached, the inner diameter of the large-diameter portion of the taper portion can be made larger than before, so that the insertability of the sensor holder is improved, The assembly workability can be improved, and the sealing performance can be improved by attaching an O-ring.

  Further, as in the invention described in claim 3, if the radial clearance between the inner diameter of the small diameter portion of the insertion hole and the outer diameter of the insertion portion of the sensor holder is set to be a maximum φ0.4 mm The insertion portion of the sensor holder can be supported by the small diameter portion, and the sealing performance can be ensured even when the O-ring is crushed or biased.

  Further, as in the invention described in claim 4, if the PT line of the cover main body is set on the end surface on the outer side of the mounting portion, the tapered portion and the cylindrical portion of the insertion hole are formed with one mold. It is possible to regulate the misalignment between the tapered portion and the cylindrical portion. Thereby, the eccentricity of the O-ring can be suppressed and the sealing performance can be ensured.

  If the width dimension of the insertion hole is set to be smaller than the dimension from the end surface of the insertion part of the sensor holder to the annular groove, as in the invention described in claim 5, an O-ring Is in contact with the inner peripheral surface of the insertion hole, the insertion portion of the sensor holder is supported by the small diameter portion of the insertion hole, and the sensor holder is stably centered. Accordingly, there is no bias at the time of insertion, and it is possible to prevent the sealing of the O-ring from becoming nonuniform and lowering the sealing performance.

  Further, as in the invention described in claim 6, if a nut to which the fixing bolt is screwed is embedded in the mounting portion of the cover body by insert molding and an annular groove is formed on the outer periphery of the nut, It is possible to prevent the nut from moving in the axial direction with respect to the main body.

  The wheel bearing device with a rotational speed detection device according to the present invention is integrally formed with an outer member in which a double row outer rolling surface is integrally formed on the inner periphery and a wheel mounting flange for mounting a wheel on one end. And a hub ring formed with 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 opposing double-row inner rolling surfaces are formed, a double-row rolling element housed in a freely rolling manner between the respective rolling surfaces of the outer member and the inner member, and the inner ring Pulsar ring that is externally fitted to the circumferential direction and the characteristics are changed at equal intervals in the circumferential direction, and is internally fitted and fixed to the opening end on the inner side of the outer member, and is formed by injection molding a synthetic resin. A bottomed cylindrical cover body having an insertion hole at a position facing the pulsar ring; And a cover made of a core metal integrally molded in the opening of the cover main body, a cylindrical insertion portion inserted into the insertion hole and embedded with a rotation speed sensor, and a mounting flange fixed to the cover main body A wheel bearing device with a rotational speed detection device, wherein the sensor holder is detachably fixed to the cover body via a fixing bolt, and the insertion hole of the cover body has a bearing inner side. Is formed in a taper shape having a gradually smaller diameter toward the end, and is slightly larger than the outer diameter of the insertion portion of the sensor holder, so that the inner diameter of the small diameter portion and the outer diameter of the insertion portion of the sensor holder Even if the radial clearance is about the same as the conventional radial clearance formed in a cylindrical shape, the inner diameter of the large diameter portion of the insertion hole can be made larger than the conventional inner diameter. Hardenability is improved, it is possible to improve the assembly workability. Moreover, since the insertion hole is formed in a taper shape, a draft angle at the time of injection molding can be secured, and productivity can be increased and cost can be reduced.

  An outer member that integrally has a vehicle body mounting flange for fixing to a knuckle that constitutes a suspension device 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 on one end The wheel mounting flange is integrally formed, and one inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery, and an axial small diameter step portion extending in the axial direction from the inner rolling surface is formed. An inner member comprising a hub ring and an inner ring press-fitted into a small-diameter step portion of the hub ring and having the other inner rolling surface opposed to the outer rolling surface of the double row on the outer periphery; The double row rolling elements accommodated in a freely rolling manner between the rolling surfaces of the side member and the inner member, and the outer ring are fitted on the inner ring, and the characteristics are alternately changed at equal intervals in the circumferential direction. Pulsar ring and inner fitting fixed to the inner side opening end of the outer member and injecting synthetic resin A bottomed cylindrical cover body having an insertion hole at a position facing the pulsar ring, and a cover made of a core metal integrally molded in an opening of the cover body, and inserted into the insertion hole, A cylindrical insertion portion in which a rotational speed sensor is embedded, and a sensor holder having a mounting flange fixed to the cover body, the sensor holder being detachably fixed to the cover body via a fixing bolt. Further, in the wheel bearing device with a rotational speed detection device, the insertion hole of the cover body has a tapered portion having a predetermined inclination angle gradually becoming a small diameter toward the bearing inward side, and a substantially central portion in the axial direction of the tapered portion. A cylindrical portion extending straight from the inner side to the inner side, and the inner diameter of the small diameter portion of the tapered portion is slightly larger than the outer diameter of the insertion portion of the sensor holder. With the constant, an annular groove formed on an outer periphery of the insertion portion, O-ring that elastically contacts the cylindrical portion of the insertion hole in the annular groove is mounted.

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. FIG. 3 (a) is an enlarged view of a main part showing a modification of the cover shown in FIG. 2 (a), and FIG. FIG. 4A is a main part enlarged view showing a state in which the sensor holder is inserted into the cover of FIG. 3, and FIG. 4B is a main part enlarged view showing the sensor holder alone. 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 the third generation on the driven wheel side, and is configured by unitizing the hub wheel 1 and the double row rolling bearing 2. The double row rolling bearing 2 includes an inner member 3, an outer member 4, and double row rolling elements (balls) 5, 5 accommodated between the members 3, 4 so as to be freely rollable. The inner member 3 indicates a hub wheel 1 and an inner ring 7 that is press-fitted and fixed to the hub wheel 1.

  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 a hub bolt 6a for fastening the wheel at a circumferentially equidistant position of the wheel mounting flange 6. Has been planted. In addition, one (outer side) inner rolling surface 1a and an axial small-diameter step portion 1b extending in the axial direction from the inner rolling surface 1a are formed on the outer periphery, and an inner ring 7 is formed on the small-diameter step portion 1b. It is press-fitted through shimeshiro. Then, the end portion of the small diameter step portion 1b is plastically deformed radially outward to form a caulking portion 1c. The caulking portion 1c causes the inner ring 7 to axially apply a predetermined bearing preload to the hub wheel 1. It is fixed in the granted state. In addition, the other (inner side) inner rolling surface 7 a is formed on the outer periphery of the inner ring 7.

  On the other hand, the outer member 4 integrally has a vehicle body mounting flange 4b fixed to a knuckle (not shown) constituting a suspension device on the outer periphery, and a double row inner rolling surface of the inner member 3 on the inner periphery. Double row outer rolling surfaces 4a, 4a facing 1a, 7a are integrally formed. The double-row rolling bearing 2 holds the double-row rolling elements 5 and 5 accommodated between the rolling surfaces 4a, 1a and 4a and 7a, and the double-row rolling elements 5 and 5 so as to roll freely. And a retainer 8 to be provided.

  Seals 9 and covers 10 are attached to both ends of the outer member 4 to seal the opening of the annular space formed between the outer member 4 and the inner member 3. The seal 9 and the cover 10 prevent the lubricating grease sealed in the bearing from leaking to the outside and preventing rainwater, dust, etc. from entering the bearing from the outside.

  The hub wheel 1 is made of medium and high carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, and includes an inner raceway surface 1a and a base portion on the inner side of the wheel mounting flange 6 that serves as a seal land portion of the seal 9. The surface hardness is hardened in the range of 58 to 64 HRC by induction hardening from 6b to the small diameter step 1b. The caulking portion 1c is an unquenched portion having a material surface hardness of 25 HRC or less after forging.

  Further, the outer member 4 is formed of medium and high carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, similar to the hub wheel 1, and at least the double row outer raceway surfaces 4a and 4a are formed by induction hardening. The surface hardness is set in the range of 58 to 64 HRC. Further, the inner ring 7 and the rolling element 5 are made of high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core part by quenching. Here, the double row rolling bearing 2 is exemplified by a double row angular contact ball bearing in which the rolling element 5 is a ball. However, the double row rolling bearing 5 is not limited to this, and is a double row using a tapered roller for the rolling element 5. A tapered roller bearing may be used. Further, the third generation structure is illustrated, but a so-called second generation structure in which a pair of inner rings are press-fitted into the hub ring may be used.

  A pulsar ring 11 is press-fitted into the outer periphery of the inner ring 7. The pulsar ring 11 includes a support ring 12 formed in an annular shape, and a magnetic encoder 13 integrally joined to the side surface of the support ring 12 by vulcanization adhesion or the like. This magnetic encoder 13 constitutes a rotary encoder for detecting the rotational speed of a wheel by mixing magnetic powder such as ferrite in an elastomer such as rubber and alternately magnetizing magnetic poles N and S in the circumferential direction.

  The support ring 12 is pressed from a ferromagnetic steel plate, for example, a ferritic stainless steel plate (JIS standard SUS430 or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC or the like). Is formed in a substantially L-shaped cross section, and has a cylindrical portion 12a that is press-fitted into the inner ring 7, and a standing plate portion 12b that extends radially inward from the cylindrical portion 12a. The magnetic encoder 13 is joined to the side surface on the inner side of the upright plate portion 12b.

  The cover 10 is fitted and fixed to the opening end of the outer member 4 on the inner side, and closes the opening of the outer member 4. The cover 10 includes a bottomed cylindrical cover main body 14 formed by injection molding a synthetic resin, and a core 15 integrally molded in an opening of the cover main body 14. The core 15 is formed in an annular shape having an L-shaped cross section by press forming a stainless steel plate having corrosion resistance. In particular, the core 15 may be a magnetic steel plate, such as a ferritic stainless steel plate (JIS SUS430, etc.) or a cold rolled steel plate (JIS SPCC, etc.). In order not to reach this, it is preferable to be formed of a non-magnetic steel plate, for example, an austenitic stainless steel plate (JIS standard SUS304 or the like).

  A mounting portion 16 that protrudes in the axial direction is integrally formed on the radially outer portion of the cover body 14, and an insertion hole 17 is formed in the mounting portion 16 at a position corresponding to the magnetic encoder 13. The sensor unit 18 is inserted into the insertion hole 17. The sensor unit 18 includes a rotation speed sensor 19 composed of a magnetic detection element that changes characteristics according to the flow direction of magnetic flux, such as a Hall element, a magnetoresistive element (MR element), and a waveform shaping that adjusts the output waveform of the magnetic detection element. It is composed of an IC or the like in which a circuit is incorporated, and constitutes an automobile ABS that detects the rotational speed of a wheel and controls its rotational speed.

  Here, in the present embodiment, the insertion hole 17 of the cover body 14 is formed in a tapered shape having a gradually decreasing diameter toward the bearing inner side (outer side), as shown in FIG. The sensor holder 20 mounted in the insertion hole 17 is integrally formed with a cylindrical insertion portion 20a and a mounting flange 20b as shown in FIG. A rotation speed sensor 19 is embedded in the sensor holder 20 made of synthetic resin.

  Further, a nut 23 having an internal thread 23a formed on the inner periphery thereof is embedded in the mounting portion 16 of the cover body 14 by insert molding. An annular groove 23b is formed on the outer periphery of the nut 23 to prevent the nut 23 from moving in the axial direction. The fixing bolt 24 has a male screw 24a that engages with the female screw 23a of the nut 23 on the outer periphery.

  The insertion hole 17 of the cover main body 14 is formed at a predetermined inclination angle α, and the inner diameter φA of the small diameter portion is set to be slightly larger than the outer diameter φC of the insertion portion 20a of the sensor holder 20. Here, the inclination angle α of the insertion hole 17 is set in the range of 2 to 20 °. Even if the radial clearance (φA−φC) between the inner diameter φA of the small diameter portion and the outer diameter φC of the insertion portion 20a of the sensor holder 20 is approximately the same as the conventional one, the inner diameter φB of the large diameter portion is larger than the conventional one. Therefore, the insertion property of the sensor holder 20 is improved, and the assembly workability can be improved. Moreover, since the insertion hole 17 is formed in a taper shape, a draft angle during injection molding can be secured, and productivity can be increased and cost can be reduced.

  FIG. 3 shows a modification of the cover 10. The cover 25 includes a bottomed cylindrical cover body 26 formed by injection molding a synthetic resin, and a core 15 integrally molded in the opening of the cover body 26. As shown in FIG. 3A, a mounting portion 16 that protrudes in the axial direction is integrally formed on the radially outer portion of the cover body 26, and an insertion hole 27 is formed in the mounting portion 16. The insertion hole 27 includes a tapered portion 27a having a predetermined inclination angle α and a cylindrical portion 27b extending straight from the substantially central portion in the axial direction of the tapered portion 27a to the inner side. The inner diameter φE of the small diameter portion is set to be slightly larger than the outer diameter φC of the insertion portion 21 a of the sensor holder 21.

  As shown in (b), the sensor holder 21 is formed integrally with a cylindrical insertion portion 21a and a mounting flange 20b. An annular groove 22 is formed on the outer periphery of the insertion portion 21a, and an O-ring 28 is attached to the annular groove 22. The O-ring 28 is in elastic contact with the cylindrical portion 27 b of the insertion hole 27. Thus, the radial clearance (φE−φC) between the inner diameter φE of the small diameter portion of the insertion hole 27 and the outer diameter φC of the insertion portion 21a of the sensor holder 21 is set to be a maximum φ0.4 mm. Thereby, the insertion part 21a of the sensor holder 21 can be supported by this small diameter part, and even if the O-ring 28 is crushed or biased, sealing performance can be ensured. Further, since the inner diameter φD of the large-diameter portion can be made larger than the conventional one, the insertion property of the sensor holder 21 can be improved, the assembling workability can be improved, and the O-ring 28 is attached to be sealed. Can be improved.

  Here, in the present embodiment, the PT line (injection mold split port) of the cover body 26 is set on the outer end surface 16 a of the mounting portion 16. As a result, the tapered portion 27a and the cylindrical portion 27b of the insertion hole 27 can be formed with a single mold, the misalignment between the tapered portion 27a and the cylindrical portion 27b can be restricted, and the eccentricity of the O-ring 28 can be suppressed. Sealing can be ensured.

  Furthermore, in this embodiment, as shown in FIG. 4, the width dimension F of the insertion hole 27 is set to be smaller than the dimension G from the end surface of the insertion portion 21 a of the sensor holder 21 to the annular groove 22. As a result, as shown in (a), the insertion portion 21a of the sensor holder 21 is supported by the small-diameter portion of the insertion hole 27 before the O-ring 28 contacts the inner peripheral surface of the insertion hole 27, so that the sensor holder 21 is stabilized. To be centered. Therefore, there is no bias at the time of insertion, and it is possible to prevent the tightness of the O-ring 28 from becoming uneven and lowering the sealing performance.

  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 an inner ring rotation type having any structure such as a drive wheel, a driven wheel, or a rolling element such as a ball or a tapered roller. .

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. (A) is a principal part enlarged view which shows the cover single-piece | unit of FIG. (B) is a principal part enlarged view which shows the state which mounted | wore the sensor holder. (A) is a principal part enlarged view which shows the modification of the cover shown to Fig.2 (a). (B) is a principal part enlarged view which shows the state which mounted | wore the sensor holder. (A) is a principal part enlarged view which shows the state which inserts a sensor holder. (B) is a principal part enlarged view which shows a sensor holder single-piece | unit. 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, 7a ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 1b ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Small diameter step 1c ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Clamping part 2 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Double row Rolling bearing 3 ························································· Outer member 4a・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer rolling surface 4b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Car body mounting flange 5 ・ ・ ・ ・ ・ ・ ・ ・.... Rolling element 6 ..... Wheel mounting flange 6a ..... Hub bolt 6b ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Base 7 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 8 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Cage 9 ... Seal 10, 25 ... Cover 11 ... ...... Pulsar ring 12 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Support ring 12a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cylinder part 12b ・ ・ ・ ・ ・ ・·······································································································・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Core 16 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mounting part 16a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Outer end faces 17, 27 ... Insert hole 18 ... Sensor unit 19 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rotational speed sensors 20, 21 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Sensor holders 20a, 21a ... Insertion section 20b ... Mounting flanges 22, 23b ... ······················································· Nut 23a ············ Fixing bolt 24a ················································・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cylinder 28 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ O-ring 51 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outside Side member 51a ··· Outward rolling surface 51b ··· Body mounting flange 52 ··· ... Inward member 53 ...・ ・ ・ ・ Ball 54 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 55 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheels 55a, 56a・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 55b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Small diameter step 56 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 57・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Retainer 58 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Clamping section 59 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Seal 60 ... Magnetic encoder 61 ... Support ring 62 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Encoder body 63 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cover 64 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cover body 65 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fitting tube 66, 73 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Projection 67 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Insertion hole 68 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Sensor unit 69 ・ ・ ・ ・ ・ ・..... Sensor holder 69a ..... Insertion part 69b ..... Mounting flange 70 ...・ ・ ・ ・ ・ ・ ・ ・ ・ Annular groove 71 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ O-ring 72 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Connector 74 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Nut 75 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Bolts A and E ············ Inner diameter B, D of insertion hole small diameter portion ········ Inner diameter C of insertion hole large diameter portion・ ・ ・ ・ ・ ・ ・ ・ Outer diameter F of insertion part ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Width dimension G of insertion hole Inclination angle dimensions alpha · · · · · · · · insertion hole from the end face of the · · · · · · insertion portion to the annular groove

Claims (6)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A hub wheel integrally having a wheel mounting flange for mounting a wheel at one end, and having a 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 accommodated in a freely rolling manner between the rolling surfaces of the outer member and the inner member;
Pulsar ring that is externally fitted to the inner ring, and the characteristics are changed alternately and at equal intervals in the circumferential direction;
A bottomed cylindrical cover body that is fitted and fixed to the opening end on the inner side of the outer member and is injection-molded with a synthetic resin, and has an insertion hole at a position facing the pulsar ring, and the cover body A cover made of a mandrel integrally molded in the opening;
A cylindrical insertion portion inserted into the insertion hole and embedded with a rotation speed sensor, and a sensor holder having a mounting flange fixed to the cover body,
In the wheel bearing device with a rotational speed detection device in which the sensor holder is detachably fixed to the cover body via a fixing bolt,
The insertion hole of the cover main body is formed in a tapered shape having a gradually smaller diameter toward the inner side of the bearing, and is formed to be slightly larger in diameter than the outer diameter of the insertion portion of the sensor holder. Wheel bearing device with rotational speed detector.   The insertion hole includes a tapered portion having a predetermined inclination angle and a cylindrical portion extending straight from the substantially central portion in the axial direction of the tapered portion to the inner side, and the inner diameter of the small diameter portion of the tapered portion is the sensor holder. An annular groove is formed on the outer periphery of the insertion portion, and an O-ring that elastically contacts the cylindrical portion of the insertion hole is formed in the annular groove. The wheel bearing device with a rotational speed detection device according to claim 1, which is mounted.   The wheel with a rotational speed detection device according to claim 1 or 2, wherein a radial clearance between an inner diameter of the small diameter portion of the insertion hole and an outer diameter of the insertion portion of the sensor holder is set to a maximum φ0.4 mm. Bearing device.   The wheel bearing device with a rotational speed detection device according to claim 2 or 3, wherein the PT line of the cover body is set on an end surface on the outer side of the mounting portion.   5. The wheel with a rotational speed detection device according to claim 1, wherein a width dimension of the insertion hole is set to be smaller than a dimension from an end surface of the insertion portion of the sensor holder to the annular groove. Bearing device.   The wheel with a rotational speed detection device according to any one of claims 1 to 5, wherein a nut to which the fixing bolt is screwed is embedded in an attachment portion of the cover body by insert molding, and an annular groove is formed on an outer periphery of the nut. Bearing device.

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