JP2009228818A - Bearing device adapted for use in wheel and having rotational speed detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device adapted for use in a wheel and having a rotational speed detection device, in which a magnetic encoder is shielded and protected by a protective cover from the outside of a bearing, in which the protective cover is fixed so as not to move, and which is thereby enhanced in reliability of detection of rotational speed. <P>SOLUTION: The protective cover 19 is formed by press working from an austenitic stainless steel plate of a non-magnetic body, and has a cylindrical fitting section 19a externally fitted in an outer member 2 and a circular plate-like shielding section 19b extending radially inward therefrom so as to close an opening between the outer member 2 and an inner ring 5. An annular groove 20 having an almost cross-sectional V-shape is formed on the end outer periphery of the outer member 2. After the fitting section 19a is pressed into the end outer periphery of the outer member 2, a crimped part 21 is formed by plastically deforming the end part of the fitting section 19a toward the annular groove 20 from the outer diameter side. The protective cover 19 is positioned and secured in the axial direction for the outward member 2 in such a state that the shielding section 19b is in close contact with an end surface 2c at the inner side of the outer member 2. <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.

  Rotation speed detection device with built-in rotation speed detection device for detecting the rotation speed of the vehicle and controlling the anti-lock brake system (ABS) while supporting the wheel of the automobile to 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. It is integrated with. A rotational speed sensor that is arranged facing this magnetic encoder and detects a change in magnetic pole of the magnetic encoder accompanying the rotation of the wheel is mounted on the knuckle after the wheel bearing device is mounted on the knuckle constituting the suspension device. .

  A structure as shown in FIG. 6 is known as an example of such a wheel bearing device with a rotational speed detection device. The wheel bearing device with a rotational speed detection device includes an outer member 50, an inner member 51, a plurality of balls 52 accommodated between the outer member 50 and the inner member 51, and the outer member 50. And a sealing device 54 for sealing an opening of an annular space formed between the inner ring 53 and the inner ring 53 constituting the inner member 51. The inner member 51 includes a hub wheel 55 and an inner ring 53 press-fitted into the hub wheel 55, and the inner ring 53 is fixed in the axial direction by a caulking portion 56.

  The seal device 54 includes an annular seal plate 57 and a slinger 58 mounted on the outer member 50 and the inner ring 53, respectively. The seal plate 57 includes a cored bar 59 having an L-shaped cross section that is fitted in the outer member 50, and a seal member 60 that is integrally joined to the cored bar 59 by vulcanization adhesion. On the other hand, the slinger 58 includes a cylindrical portion 58a fitted on the inner ring 53 and a standing plate portion 58b extending radially outward from the cylindrical portion 58a. The slinger 58 is formed in an L-shaped cross section and faces the seal plate 57. Has been placed.

  The seal member 60 includes a side lip 60a that is in sliding contact with the standing plate portion 58b of the slinger 58, and a pair of radial lips 60b and 60c that are in sliding contact with the cylindrical portion 58a. An elastic member 61 mixed with magnetic powder is vulcanized and bonded to the outer side surface of the standing plate portion 58b. The elastic member 61 constitutes a magnetic encoder in which magnetic poles N and S are alternately magnetized at equal intervals in the circumferential direction.

  A protective cover 62 made of a non-magnetic material that faces the elastic member 61 with a predetermined air gap G is disposed. The protective cover 62 has an L-shaped cross section including a cylindrical fitting portion 62a that is press-fitted into the outer diameter of the end of the outer member 50, and a side plate portion 62b that extends radially inward from the fitting portion 62a. Is formed. The side plate portion 62 b is extended to a position facing the end face of the inner ring 53, and a labyrinth clearance 63 is formed between the side plate part 62 b and the inner ring 53. The rotational speed of the wheel is detected by the magnetic sensor 64 from the elastic member 61 through the protective cover 62.

Since the protective cover 62 is made of a non-magnetic material, it does not affect the flow path of the magnetic flux, and there is no problem of a decrease in accuracy of rotational speed detection by the magnetic sensor 64. Therefore, it is possible to prevent the foreign material from being caught in the clearance between the elastic member 61 and the magnetic sensor 64, and to reliably prevent the elastic member 61 from being damaged.
JP 2002-267680 A

  However, in the case where the protective cover 62 is merely press-fitted and fixed to the outer diameter of the outer member 50 as in the conventional wheel bearing device with a rotational speed detecting device, not only the vibration during traveling of the vehicle but also the outer The moment load applied to the member 50 is repeatedly deformed, and the fitting portion 62a of the protective cover 62 may slightly move and move in the axial direction. By such movement of the protective cover 62, the labyrinth clearance 63 set between the end face of the inner ring 53 and the side plate portion 62 b of the protective cover 62 is increased, and foreign matter is caught between the elastic member 61 and the protective cover 62, and elasticity is increased. The member 61 is not only damaged, but the protective cover 62 may interfere with the magnetic sensor 64 and the magnetic sensor 64 may be damaged.

  The present invention has been made in view of such circumstances, and protects and protects the magnetic encoder from the outside of the bearing with a protective cover, and also prevents the movement by fixing the protective cover, and the reliability of rotation speed detection. An object of the present invention is to provide a wheel bearing device with an improved rotational speed detection 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 facing the double-row outer rolling surface, and each of the inner member and the outer member. A double row rolling element accommodated between the rolling surfaces so as to roll freely, a seal attached to an opening of an annular space formed by the outer member and the inner member, and an inner ring. A wheel bearing device with a rotational speed detector equipped with a magnetic encoder. A protective cover is attached to the inner side end of the outer member, and the protective cover is formed by press working from a non-magnetic austenitic stainless steel plate and is externally fitted to the outer member. And a disc-shaped shielding portion extending radially inward from the fitting portion, and closing the opening between the outer member and the inner ring so as to shield the magnetic encoder. An annular groove is formed in the outer periphery of the end of the outer member, and after the fitting portion of the protective cover is press-fitted into the outer periphery of the inner side end of the outer member, the end of the fitting portion is removed. A caulking portion is formed by plastic deformation from the radial side toward the annular groove, and the protective cover is in contact with the outer member in a state where the shielding portion is in close contact with the inner end surface of the outer member. It is positioned and fixed in the axial direction.

  Thus, in the wheel bearing device with a rotation speed detection device of the inner ring rotation type, the protective cover is mounted on the inner side end of the outer member, and this protective cover is pressed from a non-magnetic austenitic stainless steel plate. A cylindrical fitting portion formed by processing and fitted on the outer member, and a disk-shaped shielding portion extending radially inward from the fitting portion so as to shield the magnetic encoder After the opening of the outer member and the inner ring is closed, an annular groove is formed on the outer periphery of the outer member, and the fitting portion of the protective cover is pressed into the outer periphery of the inner member. Then, the end of the fitting portion is plastically deformed from the outer diameter side toward the annular groove to form a crimped portion, and the protective cover is removed while the shielding portion is in close contact with the inner side end surface of the outer member. Is fixed in the axial direction relative to the side member. It does not affect the flow path of magnetic flux, and there is no problem of deterioration in accuracy of rotational speed detection by the magnetic sensor, preventing foreign matter from getting caught in the clearance between the magnetic encoder and the magnetic sensor, and In addition to being able to reliably prevent damage, the protective cover moves in the axial direction even if the fitting portion moves slightly due to repeated deformation caused by vibration during vehicle travel and the moment load applied to the outer member. Thus, it is possible to provide a wheel bearing device with a rotational speed detection device that can improve the reliability of rotational speed detection.

  Further, as in the second aspect of the invention, the annular groove is formed in a substantially V-shaped cross section, and the crimping portion is formed in a substantially V-shaped cross section so as to correspond to the annular groove. good.

  According to a third aspect of the present invention, the annular groove is formed in a substantially trapezoidal cross section, and the end edge of the fitting portion is plastically deformed from the outer diameter side toward the annular groove to perform caulking. A part may be formed.

  Further, as in a fourth aspect of the present invention, a plurality of the caulking portions may be formed at equal intervals in the circumferential direction of the fitting portion.

  In addition, as in the invention described in claim 5, the caulking portion may be formed on the entire circumference of the fitting portion by rolling caulking. Thereby, the drop-proof strength of the protective cover can be further increased.

  According to a sixth aspect of the present invention, the inner diameter of the shielding portion is set to be smaller than the inner diameter of the magnetic encoder, and the inner diameter end of the shielding portion is slightly axially spaced from the large end surface of the inner ring. If a labyrinth seal is formed through a gap, foreign matter such as sand and metal pieces can be prevented from passing through the inner diameter end of the shielding part and entering the detection part. It is possible to reliably prevent the bite from being damaged.

  Further, as in the seventh aspect of the invention, a seal lip is integrally joined to the inner diameter end portion of the shielding portion by vulcanization adhesion, and a tip thereof is axially connected to a large end surface of the inner ring via a predetermined shimiro. If it is slidably contacted, foreign objects such as sand and metal pieces can be reliably prevented from entering the detection unit from between the shielding unit and the inner ring.

  In addition, as in the eighth aspect of the invention, if a bottom portion that closes the inner side end of the inner member from the shielding portion is formed, foreign matters such as sand and metal pieces enter the detection portion. This can be reliably prevented, and even if the inner seal is abolished, the leakage of grease can be prevented, and the cost can be reduced.

  Further, as in the invention according to claim 9, if the outer member is fitted to the knuckle through the protective cover, in the case of a combination with a knuckle made of a light alloy such as an aluminum alloy, Even if the outer member is not subjected to a special surface treatment or the like, it is possible to prevent the knuckle from causing early electric corrosion due to galvanic corrosion due to the combination of different metals.

  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 formed on the outer periphery with a double row inner rolling surface facing the outer row rolling surface of the double row, and between the respective rolling surfaces of the inner member and the outer member A double-row rolling element housed in a freely rotatable manner, a seal attached to an opening of an annular space formed by the outer member and the inner member, and a magnetic encoder disposed on the inner ring, In a wheel bearing device with a rotational speed detection device comprising: A protective cover is attached to the inner side end of the outer member, and the protective cover is formed by press working from a non-magnetic austenitic stainless steel plate and is fitted to the outer member. A joint portion and a disc-shaped shielding portion extending radially inward from the fitting portion, closing the opening of the outer member and the inner ring so as to shield the magnetic encoder, and An annular groove is formed on the outer periphery of the end of the outer member, and after the fitting portion of the protective cover is press-fitted to the outer periphery of the inner side of the outer member, the end of the fitting portion is moved to the outer diameter side. A caulking portion is formed by plastic deformation toward the annular groove, and the protective cover is in an axial direction with respect to the outer member in a state in which the shielding portion is in close contact with the inner end surface of the outer member. Influences the flow path of magnetic flux. Therefore, there is no problem of reduction in accuracy of rotation speed detection by the magnetic sensor, and foreign matter is prevented from being caught in the gap between the magnetic encoder and the magnetic sensor, and the magnetic encoder is reliably prevented from being damaged by the foreign matter being caught. Rotational speed detection by preventing the protective cover from moving in the axial direction even when the fitting part moves slightly due to repeated deformation caused by vibration during vehicle travel and the moment load applied to the outer member It is possible to provide a wheel bearing device with a rotational speed detection device that improves the reliability of the wheel.

  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 formed integrally with one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and a cylindrical small diameter step portion extending in an axial direction from the inner rolling surface; and An inner member comprising an inner ring that is press-fitted into the small-diameter step portion of the hub wheel and has the other inner rolling surface facing the outer rolling surface of the double row, and the inner member and the outer member. A double row rolling element housed between the rolling surfaces so as to roll freely, a seal mounted in an opening of an annular space formed by the outer member and the inner member, and an inner ring. In a wheel bearing device with a rotational speed detection device provided with a magnetic encoder provided A protective cover is attached to the inner side end of the outer member, and the protective cover is formed by pressing from a non-magnetic austenitic stainless steel plate and is fitted into the outer member. A joint portion and a disc-shaped shielding portion extending radially inward from the fitting portion, closing the opening of the outer member and the inner ring so as to shield the magnetic encoder, and An annular groove having a substantially V-shaped cross section is formed on the outer periphery of the end portion of the outer member, and the fitting portion of the protective cover is press-fitted into the outer periphery of the inner side end portion of the outer member. The protective cover is formed in a state in which a caulking portion having a substantially V-shaped cross section is formed by plastically deforming the portion from the outer diameter side toward the annular groove, and the shielding portion is in close contact with the inner end face of the outer member. Is fixed in the axial direction relative to the outer member. That.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device with a rotational speed detection device according to the present invention, FIG. 2 (a) is an enlarged view of a main part showing part A of FIG. ) Is a main part enlarged view showing a modification of the caulking part of FIG. 3A, and FIG. 3 is a main part enlarged view showing another modification of 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 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 for a drive wheel called a third generation, and is accommodated between the inner member 1, the outer member 2, and both members 1 and 2 so as to roll freely. Double-row rolling elements (balls) 3 and 3 are provided. The inner member 1 includes a hub ring 4 and an inner ring 5 press-fitted into the hub ring 4 through a predetermined shimiro.

  The outer member 2 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and integrally has a vehicle body mounting flange 2b for mounting to a knuckle (not shown) on the outer periphery. Double row outer rolling surfaces 2a, 2a are integrally formed. These double-row outer raceway surfaces 2a, 2a have a hardened layer with a surface hardness in the range of 54 to 64 HRC by induction hardening.

  The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and hub bolts 6a are implanted at circumferentially equidistant positions of the wheel mounting flange 6. Yes. Further, on the outer periphery, there are an inner rolling surface 4a opposite to one (outer side) of the double row outer rolling surfaces 2a, 2a, and a cylindrical small diameter step portion 4b extending in the axial direction from the inner rolling surface 4a. At the same time, a serration 4c for torque transmission is formed on the inner periphery. On the other hand, the inner ring 5 is formed on the outer periphery with an inner rolling surface 5a facing the other (inner side) of the double row outer rolling surfaces 2a, 2a, and a small-diameter step portion 4b of the hub wheel 4 via a predetermined shimoshiro. It is press-fitted. The inner ring 5 is fixed in the axial direction in a state where a predetermined bearing preload is applied by a crimping portion 7 formed by plastically deforming an end portion of the small-diameter stepped portion 4b of the hub wheel 4 radially outward. .

  Between the double row outer rolling surfaces 2a, 2a of the outer member 2 and the double row inner rolling surfaces 4a, 5a facing these, the double row rolling elements 3, 3 are respectively accommodated, and the cage 8 , 8 are held so as to roll freely. Further, seals 9 and 10 are attached to the opening of the annular space formed between the outer member 2 and the inner member 1, and leakage of the lubricating grease sealed inside the bearing and the inside of the bearing from the outside. Prevents intrusion of rainwater and dust. In addition, although the double row angular contact ball bearing which used the ball for the rolling element 3 was illustrated here, not only this but the double row tapered roller bearing which uses the tapered roller for the rolling element 3 may be sufficient. In addition, here, a third generation structure in which the inner rolling surface 4a is formed directly on the outer periphery of the hub wheel 4 is illustrated, but although not shown, a pair of inner rings are press-fitted and fixed to the small-diameter step portion of the hub wheel. A second generation structure may be used.

  The hub wheel 4 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and extends from the inner rolling surface 4a to the base 6b on the inner side of the wheel mounting flange 6 to the small diameter step 4b. The surface is hardened by induction hardening in the range of 54 to 64 HRC. In addition, the crimping part 7 is made into the surface hardness after a forge process. This facilitates the caulking process, prevents the occurrence of microcracks during the process, and not only improves the wear resistance of the base part 6b that becomes the seal land part in sliding contact with the seal 9, but also improves the wheel mounting flange 6. It has sufficient mechanical strength against the applied rotational bending load, and the durability of the hub wheel 4 is improved. The inner ring 5 and the rolling element 3 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 portion by quenching.

  The seal 9 on the outer side of the seals 9 and 10 includes a core metal 11 press-fitted into the inner periphery of the outer side end portion of the outer member 2 via a predetermined shimiro, and a seal member joined to the core metal 11. It is comprised by the integral seal | sticker which consists of 12. The core metal 11 is formed by pressing a cold-rolled steel plate (JIS standard SPCC system or the like).

  On the other hand, the sealing member 12 is made of synthetic rubber such as nitrile rubber and is integrally joined to the core metal 11 by vulcanization adhesion. This seal member 12 is formed to be inclined outward in the radial direction, and is provided with a side lip 12a that is in sliding contact with a side surface on the inner side of the wheel mounting flange 6 with a predetermined squeeze, and a base 6b that is formed with a circular cross section. A radial lip 12b that is slidably contacted with the squeeze and a grease lip 12c that is inclined toward the inner side of the bearing.

  Further, as shown in an enlarged view in FIG. 2A, the inner-side seal 10 is configured by a so-called pack seal including an annular seal plate 13 and a slinger 14 that are arranged to face each other. The seal plate 13 includes a cored bar 15 attached to the outer member 2 and a seal member 16 integrally joined to the cored bar 15 by vulcanization adhesion. The core 15 is formed by pressing from a steel plate having rust prevention ability such as an austenitic stainless steel plate (JIS standard SUS304, etc.) or a rust-proof cold rolled steel plate (JIS standard SPCC, etc.). The cross section is substantially L-shaped.

  The seal member 16 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and integrally includes a side lip 16a extending obliquely outward in the radial direction, a grease lip 16b formed in a bifurcated shape, and an intermediate lip 16c. Have.

  On the other hand, the slinger 14 has a substantially L-shaped cross section, and includes a cylindrical portion 14a that is press-fitted into the outer diameter of the inner ring 5, and a standing plate portion 14b that extends radially outward from the cylindrical portion 14a. The side lip 16a of the seal member 16 is slidably contacted with the standing plate portion 14b with a predetermined squeezing force, and the grease lip 16b and the intermediate lip 16c are slidably contacted with the cylindrical portion 14a with a predetermined squeezing force. Further, the standing plate portion 14 b of the slinger 14 is opposed to the seal plate 13 through a slight radial clearance to form a labyrinth seal 17.

  In addition, a magnetic encoder 18 in which magnetic powder such as ferrite is mixed into synthetic rubber is integrally joined to the inner side surface of the standing plate portion 14b by vulcanization adhesion or the like. This magnetic encoder 18 is magnetized with magnetic poles N and S alternately at equal pitches in the circumferential direction, and constitutes a rotary encoder for detecting the rotational speed of the wheel.

  The slinger 14 is formed by pressing 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. Thereby, it is possible to prevent the slinger 14 from rusting and to increase the magnetic output of the magnetic encoder 18 and to ensure stable detection accuracy.

  A protective cover 19 is attached to the inner side end of the outer member 2. This protective cover 19 is formed in a substantially L-shaped cross section by press working from a non-magnetic austenitic stainless steel plate (JIS standard SUS304 series), and is a cylindrical shape that is press-fitted into the outer periphery of the end of the outer member 2. It has a fitting part 19a and a disk-shaped shielding part 19b extending radially inward from the fitting part 19a. Further, the inner diameter φd1 of the shielding portion 19b is set to be smaller than the inner diameter φd2 of the magnetic encoder 18, and the inner diameter end portion of the shielding portion 19b is opposed to the large end surface 5b of the inner ring 5 via a slight axial clearance, thereby providing a labyrinth seal. 23 is formed. This prevents foreign matters such as sand and metal pieces from passing through the inner diameter end of the shielding portion 19b and entering the detection portion, and reliably prevents the foreign matter from biting into the magnetic encoder 18 and damaging the detection portion. Can be prevented.

  Here, an annular groove 20 having a substantially V-shaped cross section is formed on the outer periphery of the end portion of the outer member 2. Further, after the fitting portion 19a of the protective cover 19 is press-fitted to the outer periphery of the inner side end portion of the outer member 2, the end portion of the fitting portion 19a is moved from the outer diameter side by a crimping jig (not shown). A plurality of caulking portions 21 are formed at equal intervals in the circumferential direction by being plastically deformed toward the annular groove 20. The caulking portion 21 is engaged with the annular groove 20 in a state where the shielding portion 19b of the protective cover 19 is in close contact with the inner end face 2c of the outer member 2, and the protective cover 19 is pivoted with respect to the outer member 2. Positioned and fixed in the direction.

  Thus, in the present embodiment, the openings of the outer member 2 and the inner ring 5 are closed so as to shield the magnetic encoder 18, and the magnetic sensor 22 is disposed on the inner side of the shielding portion 19b. Since the magnetic encoder 18 is opposed to the magnetic encoder 18 via the protective cover 19 via a predetermined axial clearance (air gap), the magnetic flux flow path is not affected and the accuracy of rotation speed detection by the magnetic sensor 22 is reduced. Absent. Therefore, in combination with the labyrinth seal 23 between the shielding portion 19b and the inner ring 5, foreign matter is prevented from being caught in the clearance between the magnetic encoder 18 and the magnetic sensor 22, and the magnetic encoder 18 is prevented from being caught by foreign matter. The protective cover 19 can be reliably prevented from being damaged, and the protective cover 19 can be moved in the axial direction even if the fitting portion 19a slightly moves due to repeated deformation caused by vibration during traveling of the vehicle or a moment load applied to the outer member 2. Never move on.

  The magnetic sensor 22 incorporates a magnetic detecting element such as a Hall element, a magnetoresistive element (MR element) or the like that changes its characteristics according to the flow direction of magnetic flux, and a waveform shaping circuit that adjusts the output waveform of the magnetic detecting element. IC. Further, here, the magnetic encoder 18 made of rubber is illustrated, but the invention is not limited to this. For example, the magnetic encoder 18 is made of sintered metal obtained by hardening a ferromagnetic powder made of synthetic resin or ferrite with a metal binder instead of rubber. It may be.

  Furthermore, in this embodiment, the following features are provided in addition to the features described above. That is, the protective cover 19 is formed of a non-magnetic austenitic stainless steel plate, and the outer member 2 is fitted to the knuckle through the protective cover 19, so that the protective cover 19 is prevented from rusting, In the case of a combination with a knuckle made of a light alloy such as an aluminum alloy, even if the outer member 2 is not subjected to special surface treatment, corrosion due to the combination of different metals, that is, the outer member 2 made of steel and the light alloy When two types of metal are exposed to a corrosive environment with the alloy knuckle in contact with each other, the metal with the lower potential difference (in this case, the light alloy knuckle) becomes the anode. The so-called galvanic corrosion that causes corrosion at an early stage can prevent the knuckle from causing electric corrosion at an early stage.

  As shown in FIG. 2B, the shape of the caulking portion 24 may be changed. That is, after the annular groove 25 having a substantially trapezoidal cross section is formed on the outer periphery of the end portion of the outer member 2 and the fitting portion 19a of the protective cover 19 is press-fitted to the outer periphery of the end portion on the inner side of the outer member 2. Even if the edge of the fitting part 19a is plastically deformed from the outer diameter side toward the annular groove 25 by a caulking jig (not shown), and a plurality of caulking parts 24 are formed in a circumferentially uniform manner. good.

  Here, a plurality of the caulking portions 21 and 24 are illustrated as being formed in a circumferentially equidistant manner, but the present invention is not limited thereto, and may be formed on the entire circumference of the fitting portion 19a by rolling caulking. . Thereby, the drop-proof strength of the protective cover 19 can be further increased.

  Next, a modification of FIG. 2A is shown in FIG. In this modified example, only the configuration of the protective cover is partially different, and other parts having the same parts or the same functions as those of the above-described embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The protective cover 26 is formed in a substantially L-shaped cross section by press working from a non-magnetic austenitic stainless steel plate (JIS standard SUS304 series), and is cylindrically inserted into the outer periphery of the end of the outer member 2. It has a fitting part 19a and a disk-shaped shielding part 26a extending radially inward from the fitting part 19a. A seal lip 27 is integrally joined to the inner diameter end portion of the shielding portion 26a by vulcanization adhesion.

  The seal lip 27 is made of synthetic rubber such as NBR, and the tip thereof is in sliding contact with the large end surface 5b of the inner ring 5 in the axial direction via a predetermined shimoshiro. Thereby, it is possible to reliably prevent foreign matters such as sand and metal pieces from entering the detection portion from between the shielding portion 26 a and the inner ring 5.

  FIG. 4 is a longitudinal sectional view showing a second embodiment of the wheel bearing device with a rotational speed detection device according to the present invention, and FIG. 5 is an enlarged view of a main part showing a portion B of FIG. In this embodiment, the above-described embodiment is applied to the driven wheel side, and other parts having the same parts or the same functions as those of the above-described embodiment are denoted by the same reference numerals, and detailed description thereof will be given. Omitted.

  This wheel bearing device with a rotational speed detector includes an outer member 2, a hub ring 28, an inner member 29 comprising an inner ring 5 press-fitted into the hub ring 28 via a predetermined shimoshiro, and both members 2 , 29 are provided with double-row rolling elements 3 and 3 accommodated so as to roll freely.

  The hub wheel 28 integrally has a wheel mounting flange 6 at an end portion on the outer side, and has one (outer side) inner rolling surface 4a on the outer periphery and a cylindrical shape extending in the axial direction from the inner rolling surface 4a. A small diameter step 4b is formed. The inner ring 5 is press-fitted into the small-diameter step portion 4b via a predetermined shimiro, and is fixed in the axial direction with a predetermined bearing preload applied by the crimping portion 7.

  The hub wheel 28 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and extends from the inner rolling surface 4a to the small diameter step portion 4b from the base portion 6b on the inner side of the wheel mounting flange 6. The surface is hardened by induction hardening in the range of 54 to 64 HRC.

  A protective cover 30 is attached to the inner side end of the outer member 2. The protective cover 30 is formed into a cup shape by press working from a non-magnetic austenitic stainless steel plate (JIS standard SUS304 type), and as shown in an enlarged view in FIG. A cylindrical fitting portion 19a that is press-fitted into the disc, a disc-shaped shielding portion 19b that extends radially inward from the fitting portion 19a, and an inner side end of the inner member 29 from the shielding portion 19b. And a bottom portion 30a to be closed. Accordingly, it is possible to reliably prevent foreign matters such as sand and metal pieces from entering the detection portion, and prevent leakage of grease even if the seal plate 13 constituting the inner side seal 10 is eliminated. Therefore, cost reduction can be achieved.

  Here, as in the first embodiment described above, an annular groove 20 having a substantially V-shaped cross section is formed on the outer periphery of the end portion of the outer member 2, and a caulking portion formed in the fitting portion 19 a of the protective cover 30. 21 is engaged. As a result, the protective cover 30 is positioned and fixed in the axial direction with respect to the outer member 2, and repeatedly deforms due to vibration during traveling of the vehicle and a moment load applied to the outer member 2, and the fitting portion 19a slightly moves. However, the protective cover 30 does not move in the axial direction.

  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 rotational speed detecting device according to the present invention can be applied to a wheel bearing device having a second or third generation structure having an inner ring rotating structure.

1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device with a rotation speed detection device according to the present invention. (A) is a principal part enlarged view which shows the A section of FIG. (B) is a principal part enlarged view which shows the modification of the crimping part of (a). It is a principal part enlarged view which shows the other modification of Fig.2 (a). It is a longitudinal cross-sectional view which shows 2nd 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 B section of FIG. It is a principal part enlarged view which shows the conventional wheel bearing apparatus with a rotational speed detection apparatus.

Explanation of symbols

1, 29 ..... Inner member 2 ... Outer member 2a ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outside rolling surface 2b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Car body mounting flange 2c ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ End face 3 on the inner side ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rolling elements 4, 28 ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheel 4a, 5a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 4b ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ Small diameter step 4c ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Serration 5 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ Inner ring 5b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Large end surface 6 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting 6a ... hub bolt 6b ... base 7 on the inner side ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Clamping section 8 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cage 9 ..... Outer side seal 10 ..... Inner side seals 11, 15 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Cores 12 and 16 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal members 12a and 16a ・ ・ ・ ・ ・ ・ ・ ・・ Side lip 12b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Radial lip 12c, 16b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Grease lip 13 ・ ・ ・ ・ ・ ・..... Seal plate 14 ... ... Slinger 14a ... Cylindrical part 14b ...・ Standing plate portion 16c ・ ・ ・ Intermediate lip 17, 23 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Labyrinth seal 18 ・ ・ ・..... Magnetic encoder 19, 26, 30 ..... Protective cover 19a ... ············· Fitting parts 19b, 26a ·················· Shielding portions 20, 25 21, 24 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Clamping section 22 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Magnetic sensor 27 ..... seal lip 30a ...・ ・ ・ ・ ・ ・ ・ ・ Bottom 50 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ External member 51 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Inner member 52 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Ball 53 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 54 ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Sealing device 55 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub wheel 56 ・ ・ ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fastening part 57 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal plate 58・ ・ ・ ・ ・ ・ Slinger 58a ・ ・ ・ ・ ・ ・ ・ ・ Cylindrical part 58b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Standing plate part 59 ······························· 60・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Side lips 60b, 60c ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Radial lip 61 ・ ・ ・ ・ ・ ・ ・ ・······ Elastic member 62 ···························· Protective cover 62a Joint part 62b ... side plate part 63 ... labyrinth clearance 64 ... ..... Magnetic sensor d1 ..... Inner diameter d2 of shielding part ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner diameter G of magnetic encoder ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Air gap

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 movably between the rolling surfaces of the inner member and the outer member;
A seal attached to an opening of an annular space formed by the outer member and the inner member;
In the wheel bearing device with a rotational speed detection device provided with a magnetic encoder disposed on the inner ring,
A protective cover is attached to the inner side end of the outer member, and the protective cover is formed by pressing from a non-magnetic austenitic stainless steel plate and is fitted into the outer member. A joint portion and a disc-shaped shielding portion extending radially inward from the fitting portion, closing the opening of the outer member and the inner ring so as to shield the magnetic encoder, and An annular groove is formed on the outer periphery of the end of the outer member, and after the fitting portion of the protective cover is press-fitted to the outer periphery of the inner side of the outer member, the end of the fitting portion is moved to the outer diameter side. A caulking portion is formed by plastic deformation toward the annular groove, and the protective cover is in an axial direction with respect to the outer member in a state in which the shielding portion is in close contact with the inner end surface of the outer member. Rotation speed detection characterized by being fixed to Equipped wheel bearing apparatus.   The wheel bearing with a rotation speed detecting device according to claim 1, wherein the annular groove is formed in a substantially V-shaped cross section, and the crimping portion is formed in a substantially V-shaped cross section so as to correspond to the annular groove. apparatus.   2. The rotation according to claim 1, wherein the annular groove is formed in a substantially trapezoidal cross section, and an end edge of the fitting portion is plastically deformed from an outer diameter side toward the annular groove to form a crimp portion. Wheel bearing device with speed detector.   The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 3, wherein a plurality of the caulking portions are formed at equal intervals in the circumferential direction of the fitting portion.   The wheel bearing device with a rotation speed detecting device according to any one of claims 1 to 3, wherein the caulking portion is formed on the entire circumference of the fitting portion by rolling caulking.   An inner diameter of the shielding portion is set to be smaller than an inner diameter of the magnetic encoder, and an inner diameter end portion of the shielding portion is opposed to a large end surface of the inner ring through a slight axial clearance to form a labyrinth seal. The wheel bearing apparatus with a rotational speed detection apparatus in any one of Claims 1 thru | or 5.   The seal lip is integrally joined to the inner diameter end portion of the shielding portion by vulcanization adhesion, and the tip thereof is slidably contacted with the large end surface of the inner ring in the axial direction via a predetermined shimiro. A bearing device for a wheel with a rotational speed detection device according to claim 1.   The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 5, wherein a bottom portion that closes an inner side end portion of the inner member from the shielding portion is formed.   The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 8, wherein the outer member is fitted to the knuckle through the protective cover.

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