JP2008170219A - Rotational speed detection device and bearing device for wheel with rotational speed detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotational speed detection device and a bearing device for a wheel with a rotational speed detecting device capable of managing air gap at higher precision and increasing reliability for detecting the rotational speed of a wheel without generating airtightness failure. <P>SOLUTION: This device comprises: a sensor holder 15, formed annularly, fitted at the end of an external member 4; a fitting ring 16; and a supporting part 17 joined with the fitting ring 16. A level difference ΔA is placed between the outer peripheral face of the supporting part 17 and the outer peripheral face of the fitting part 16a of the fitting ring 16. The level difference ΔA is circular arc shape of a certain width extending along the outer peripheral face of the supporting part 17. When the fitting part 16a of the fitting ring 16 is pressed and fixed in the external member 4, not only the part where the supporting part 17 is not placed but also the flange part 16b of the outer peripheral part of the supporting part 17 in the flange part 16b of the fitting ring 16 can be pressed with a press fit jig. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  Rotation speed detection device with built-in rotation speed detection device to detect the rotation speed of the wheel to control the anti-lock brake system (ABS) while supporting the wheel of the automobile rotatably with the suspension system Wheel bearing devices are generally known. Conventionally, in such a wheel bearing device, a sealing device is provided between an inner member and an outer member that are in rolling contact with a rolling element, and a magnetic encoder in which magnetic poles are alternately arranged in a circumferential direction is provided as the sealing device. In addition, the rotational speed detecting device is constituted by a magnetic encoder and a rotational speed sensor that is arranged facing the magnetic encoder and detects a magnetic pole change of the magnetic encoder accompanying the rotation of the wheel.

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

  Patent Document 1 discloses an example of such a wheel bearing device with a rotational speed detection device. In this example, an encoder fitted to the inner ring, an annular sensor holder mounted on the end of the outer member so as to face the encoder, and an integral mold on the sensor holder, and a predetermined axial direction on the encoder In a wheel bearing device with a rotational speed detection device provided with a rotational speed sensor opposed to each other through a clearance, the encoder comprises an annular magnetic encoder, and a seal is provided on the inboard side of the encoder via a sensor holder. The seals are mounted on the sensor holder and the inner ring, respectively, and are composed of annular first and second seal plates disposed opposite to each other.

In such a wheel bearing device with a rotational speed detection device, a dedicated press-fitting jig is used when the sensor holder is attached to the wheel bearing device. More specifically, the metal fitting ring constituting the sensor holder is pressed and fixed to the outer member by pressing with a substantially C-shaped press-fitting jig. Here, the press-fitting jig is substantially C-shaped because the holding part for holding the sensor is made of resin, so that a part of the annular press-fitting jig is not applied to the part. This is because it is cut out.
Japanese Patent Laying-Open No. 2005-300289

  However, when the fitting ring is press-fitted and fixed with a substantially C-type press-fitting jig, no pressure is directly applied to the fitting ring in the portion where the holding portion exists, so the fitting ring in that portion is the outer member. There is a problem that the air gap is not stable and the airtightness may be deteriorated.

  The present invention has been made in view of such circumstances, and more accurate air gap management is possible, without causing poor airtightness, and improving the reliability of wheel rotation speed detection. An object of the present invention is to provide a rotational speed detection device and a wheel bearing device with a rotational speed detection device.

  In order to achieve such an object, the present invention includes an encoder and an annular sensor holder disposed so as to face the encoder, and the sensor holder is an annular fitting ring made of a steel plate. The holding ring is integrally molded with the fitting ring and includes a rotation speed sensor facing the encoder, and a step is formed between the outer circumferential surface of the holding portion and the outer circumferential surface of the fitting ring. Adopted the configuration.

  As described above, since the step is formed between the outer peripheral surface of the holding portion and the outer peripheral surface of the fitting ring, when the fitting ring is press-fitted and fixed to the outer member of the wheel bearing device, the fitting ring Of these, not only the portion where the holding portion is not provided, but also the outer peripheral portion of the holding portion can be pressed with the press-fitting jig. Therefore, since the shape of the press-fitting jig can be an annular shape instead of a substantially C shape, the pressing amount can be made constant over the entire circumference of the fitting ring. As a result, air gap management with higher accuracy is possible, and the reliability of wheel rotation speed detection can be improved without causing poor airtightness.

  In the present invention, it is preferable that the step has an arc shape having a certain width extending along the outer peripheral surface of the holding portion. Thereby, since a press-fit jig | tool can be made into an annular | circular shape, the amount of press becomes constant over the perimeter of a fitting ring.

  The present invention also includes an outer member integrally having a vehicle body mounting flange for mounting on a suspension device on the outer periphery, a double row outer rolling surface formed on the inner periphery, and a wheel for mounting a wheel on the outer periphery. A hub ring integrally having a mounting flange and formed with a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and an outer joint member of an inner ring or a constant velocity universal joint press-fitted into the small-diameter step portion of the hub ring; An inner member formed on the outer periphery and formed with an inner rolling surface facing the outer rolling surface of the double row, and accommodated in a freely rollable manner between the respective rolling surfaces of the outer member and the inner member. A double-row rolling element, an encoder externally fitted to the outer ring member of the inner ring or constant velocity universal joint, and an annular sensor mounted on the end of the outer member so as to face the encoder A sensor holder, the sensor holder being made of a steel plate and a ring And a holding portion provided with a rotation speed sensor that is integrally molded with the fitting ring and faces the encoder, and between the outer peripheral surface of the holding portion and the outer peripheral surface of the fitting ring. A step can be formed.

  As a result, it is possible to provide a wheel bearing device with a rotation speed detection device that can perform air gap management with higher accuracy, does not cause airtightness, and can improve the reliability of wheel rotation speed detection.

  A wheel bearing device with a rotational speed detection device according to the present invention includes an encoder and an annular sensor holder disposed so as to face the encoder, and the sensor holder is made of a steel plate and has an annular shape. A fitting ring and a holding part that is integrally molded with the fitting ring and includes a rotation speed sensor facing the encoder, and a step is formed between the outer peripheral surface of the holding part and the outer peripheral surface of the fitting ring. Because it is formed, the outer periphery of the holding part can also be pressed with a press-fitting jig, enabling more accurate air gap management, without causing airtightness, and reliability in detecting the rotational speed of the wheel. Can be improved.

  An encoder, and an annular sensor holder disposed so as to face the encoder, the sensor holder being made of a steel plate and having an annular shape, and being integrally molded with the fitting ring, The holding portion includes a rotation speed sensor facing the encoder, and a step is formed between the outer peripheral surface of the holding portion and the outer peripheral surface of the fitting ring.

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

  This wheel bearing device with a rotational speed detection device is for a drive wheel and has a so-called third generation configuration in which the hub wheel 1 and the double row rolling bearing 2 are unitized.

  The double-row rolling bearing 2 includes an outer member 4, an inner member 3, and double-row rolling elements (balls) 5 and 5, and the outer member 4 has carbon 0.40 to 0. It is made of medium carbon steel containing 80 wt%, and integrally has a vehicle body mounting flange 4b for mounting to a knuckle (not shown) on the outer periphery. Double rows of outer rolling surfaces 4a and 4a are formed on the inner periphery, and a hardened layer is formed with a surface hardness in the range of 54 to 64 HRC by induction hardening.

  On the other hand, the hub wheel 1 integrally has a wheel mounting flange 7 for mounting a wheel (not shown) at an end portion on the outboard side, and a hub bolt 7a is planted at a circumferentially equidistant position of the wheel mounting flange 7. It is installed. Further, on the outer periphery, one inner rolling surface 1a facing the double row outer rolling surfaces 4a, 4a and a cylindrical small-diameter step portion 1b extending in the axial direction from the inner rolling surface 1a are formed. Yes. A serration (or spline) 1c is formed on the inner periphery of the hub wheel 1, and an outer joint member (not shown) constituting a constant velocity universal joint is fitted through the serration 1c. The inner ring 6 is press-fitted into the small-diameter step portion 1b, and the other inner rolling surface 6a facing the double-row outer rolling surfaces 4a and 4a is formed on the outer periphery thereof. Here, the inner member 3 refers to the hub wheel 1 and the inner ring 6 press-fitted into the hub wheel 1.

  Double row rolling elements 5, 5 are accommodated between outer rolling surfaces 4a, 4a of outer member 4 and double row inner rolling surfaces 1a, 6a facing these, respectively, by retainers 9, 9. It is held freely rolling. Further, seals 10 and 11 are attached to the end portion of the outer member 4 to prevent leakage of the lubricating grease sealed inside the bearing and intrusion of rainwater, dust and the like into the bearing from the outside.

  The hub wheel 1 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the like from the seal land portion where the seal 10 on the outboard side is in sliding contact to the inner rolling surface 1a and the small diameter step portion 1b Thus, a hardened layer is formed with a surface hardness in the range of 54 to 64 HRC by induction hardening. As a result, the seal land that is the base of the wheel mounting flange 7 not only has improved wear resistance, but also has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 7. The durability of 1 is further improved.

  In the present embodiment, as shown in an enlarged view in FIG. 2, the sensor holder 15 formed in an annular shape is attached to the end of the outer member 4, and is coupled to the fitting ring 16 and the fitting ring 16. And holding part 17.

  The fitting ring 16 has a cylindrical fitting portion 16a that is press-fitted into the outer periphery of the outer member 4, a flange portion 16b that extends radially inward from the fitting portion 16a, and an obliquely inward radial direction. The inclined portion 16c and a cylindrical portion 16d extending in the axial direction from the inclined portion 16c are formed in an annular shape as a whole. The fitting ring 16 is formed by pressing a corrosion-resistant stainless steel plate or a plated steel plate. Alternatively, the steel sheet is subjected to rust prevention treatment after press molding. In addition, perforations 18 are formed at a plurality of locations in the circumferential direction of the inclined portion 16c, and the holding portion 17 is integrally molded with a synthetic resin. The sensor holder 15 is press-fitted and fixed to the end portion of the outer member 4 while the seal 11 is fitted in the cylindrical portion 16 d of the sensor holder 15 and the flange portion 16 b is in close contact with the end surface of the outer member 4. Has been.

  A rotation speed sensor 20 is embedded in the holding portion 17 so as to face a magnetic encoder 19 described later via a predetermined axial clearance. The rotation speed sensor 20 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 IC.

  In the present embodiment, a step ΔA is provided between the outer peripheral surface of the holding portion 17 and the outer peripheral surface of the fitting portion 16 a of the fitting ring 16. That is, the diameter of the outer peripheral surface of the holding portion 17 having a substantially arc shape is smaller than the diameter of the outer peripheral surface of the fitting portion 16 a, and the flange portion 16 b of the fitting ring 16 is exposed at the outer peripheral portion of the holding portion 17. ing. The step ΔA has an arc shape with a certain width that spreads along the outer peripheral surface of the holding portion 17.

  In FIG. 3, the contact range between the fitting ring 16 and the press-fitting jig when the fitting ring 16 is pressed with the press-fitting jig is shown by hatching. As shown in this figure, when the fitting portion 16a of the fitting ring 16 is press-fitted and fixed to the outer member 4, only the portion of the flange portion 16b of the fitting ring 16 where the holding portion 17 is not provided. In addition, the portion of the flange portion 16b on the outer peripheral portion of the holding portion 17 can also be pressed by the press-fitting jig. Therefore, since the shape of the press-fitting jig can be an annular shape instead of a substantially C shape, the pressing amount can be made constant over the entire circumference of the fitting ring 16. As a result, air gap management with higher accuracy is possible, and the reliability of wheel rotation speed detection can be improved without causing poor airtightness.

  The inboard side seal 11 is attached to the sensor holder 15 and the inner ring 6 respectively, and is composed of annular first and second seal plates 21 and 22 each having a substantially L-shaped cross section. ing. The second seal plate 22 includes a cylindrical portion 22a that is externally fitted to the inner ring 6, and a standing plate portion 22b that extends radially outward from the cylindrical portion 22a. The second seal plate 22 is formed by pressing an austenitic stainless steel plate (JIS standard SUS304 type or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC type or the like). Yes.

  On the other hand, the first seal plate 21 includes a cylindrical portion 21a fitted in the cylindrical portion 16d of the fitting ring 16, and a standing plate portion 21b extending radially inward from one end of the cylindrical portion 21a. A seal member 24 integrally having a lip 24a, a grease lip 24b, and an intermediate lip 24c is vulcanized and bonded. The seal member 24 is made of an elastic member such as rubber. Here, the side lip 24 a is in sliding contact with the upright plate portion 22 b of the second seal plate 22, and the grease lip 24 b and the intermediate lip 24 c are in sliding contact with the cylindrical portion 22 a of the second seal plate 22.

  A steel plate base 25 is disposed on the opposite side of the seal 11 across the holding portion 17 of the sensor holder 15. The base 25 includes a cylindrical portion 25a that is externally fitted to the inner ring 6, and a standing plate portion 25b that extends radially outward from the cylindrical portion 25a, and has a substantially L-shaped cross section. A magnetic encoder 19 in which magnetic material powder such as ferrite is mixed into an elastomer such as rubber is integrally vulcanized and bonded to the surface on the inboard side of the standing plate portion 25b. This magnetic encoder 19 is magnetized with magnetic poles N and S alternately in the circumferential direction, and constitutes a rotary encoder for detecting wheel rotation speed.

  As described above, the rotational speed sensor 20 is disposed in the annular sensor holder 15, and the seal 11 is fitted on the inboard side of the rotational speed sensor 20, so that the assembly line of the finished product manufacturer of the automobile can be used. Even before the outer joint member 12 is fitted into the hub wheel 1 including during transportation, or even during actual running that is a harsh environment, the magnetic encoder 19 and the detection unit of the rotation speed sensor 20 are not connected. It is possible to reliably prevent foreign substances such as magnetic powder from entering from the outside. Therefore, the reliability of detecting the rotational speed of the wheel can be significantly improved. In addition, the radial direction can be reduced, the surroundings of the rotation speed sensor 20 and the like can be simplified, and the assembly workability is further improved.

  In the present embodiment, as an example of the rotational speed detection apparatus, an active type rotational speed detection apparatus including the magnetic encoder 19 and the rotational speed sensor 20 including a magnetic detection element such as a Hall element is illustrated. The rotational speed detection device is not limited to this, and may be, for example, a passive type composed of a magnetic encoder, a magnet, and an annular coil wound around.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

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

It is a longitudinal cross-sectional view which shows embodiment of the wheel bearing apparatus with a rotational speed detection apparatus which concerns on this invention. It is a principal part enlarged view of FIG. It is a side view of a sensor holder.

Explanation of symbols

1 ... hub wheel 1a, 6a ... inner rolling surface 1b ... ·············· Small diameter step 1c ·········· Double row rolling bearing 3・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer member 4a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer rolling surface 4b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Body mounting flange 5 ... Rolling element 6 ...・ ・ ・ ・ ・ Inner ring 7 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 7a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・9 Bolt 9 ... Retainer 10 ... Outboard side seal 11 ······················ Seal 15 on the inboard side ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fitting ring 16a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fitting part 16b ・ ・ ・ ・ ・ ・ ・ ・········ 16c ·······················································・ ・ Cylindrical part 17 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Holding part 18 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Perforation 19 ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Magnetic encoder 20 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Rotational speed sensor 21 ... 1st seal plate 21a ... ... Cylindrical part 21b ... Standing plate 22 ... Second seal plate 22a ... ... Cylindrical part 22b ... Vertical plate part 24 ...・ ・ ・ ・ ・ ・ ・ ・ ・ Seal member 24a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Side lip 24b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ Grease lip 24c ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Intermediate lip 25 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Base 25a ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ Cylindrical part 25b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Standing board part ΔA ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Step

Claims (4)

An encoder and an annular sensor holder disposed to face the encoder;
The sensor holder is made of a steel ring-shaped fitting ring, and a holding unit that is integrally molded with the fitting ring and includes a rotation speed sensor that faces the encoder.
A rotational speed detecting device, wherein a step is formed between an outer peripheral surface of the holding portion and an outer peripheral surface of the fitting ring.   The rotational speed detection device according to claim 1, wherein the step has an arc shape having a certain width extending along an outer peripheral surface of the holding portion. An outer member integrally having a vehicle body mounting flange for mounting to a suspension device on the outer periphery, and a double row outer rolling surface formed on the inner periphery;
A hub wheel integrally having a wheel mounting flange for mounting a wheel on the outer periphery and having a cylindrical small-diameter step portion extending in the axial direction on the outer periphery, and an inner ring or the like press-fitted into the small-diameter step portion of the hub wheel An inner member formed of an outer joint member of a speed universal joint and having an inner rolling surface facing the outer rolling surface of the double row on the outer periphery;
A double row rolling element housed so as to be freely rollable between the rolling surfaces of the outer member and the inner member;
An encoder externally fitted to the outer ring member of the inner ring or constant velocity universal joint, and an annular sensor holder attached to the end of the outer member so as to face the encoder,
The sensor holder is made of a steel ring-shaped fitting ring, and a holding unit that is integrally molded with the fitting ring and includes a rotation speed sensor that faces the encoder.
A wheel bearing device with a rotational speed detecting device, wherein a step is formed between an outer peripheral surface of the holding portion and an outer peripheral surface of the fitting ring.   4. The wheel bearing device with a rotation speed detecting device according to claim 3, wherein the step has an arc shape having a certain width extending along an outer peripheral surface of the holding portion.

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