JP2011149836A - Bearing device for wheel with rotational speed detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a wheel with a rotation speed detection device capable of improving reliability for rotational speed detection by heightening positioning accuracy, while suppressing deformation by heightening rigidity of a protection cover. <P>SOLUTION: The protection cover 10 includes: a cylindrical fitting part 10a formed to have a cup shape by injection molding of a synthetic resin which is a nonmagnetic body, and inserted into an outer member 2; a collar part 10b formed to protrude therefrom to the outward in the radial direction, and in close contact with the end surface 2c of the outer member 2; and a bottom part 10c extending therefrom to the inward in the radial direction, for blocking the end on the inner side of an inner member 1. A metal core 15 formed from a steel plate by press work so as to have an approximately L-shaped section is insert-molded on a portion of the fitting part 10a and the collar part 10b, and a detection part 16 of a rotational speed sensor is positioned close to the outside surface of the bottom part 10c, and is faced to a magnetic encoder 14 through a prescribed air gap, and a rib 17 is formed to protrude on the outside surface of the bottom part 10c except the faced portion. <P>COPYRIGHT: (C)2011,JPO&amp;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. 23 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, and a plurality of balls 52 accommodated between the outer member 50 and the inner member 51. The inner member 51 includes a hub ring 53 and an inner ring 54 press-fitted into the hub ring 53.

  The outer member 50 integrally has a vehicle body mounting flange 50b fixed to the knuckle 65 constituting the suspension device on the outer periphery, and double row outer rolling surfaces 50a and 50a are integrally formed on the inner periphery. A sensor 63 is supported and fixed to the knuckle 65 by a screw 66.

  The hub wheel 53 integrally has a wheel mounting flange 55 for mounting a wheel (not shown) at one end, an inner rolling surface 53a on the outer periphery, and a small diameter step extending in the axial direction from the inner rolling surface 53a. A portion 53b is formed. The inner ring 54 has an inner rolling surface 54a formed on the outer periphery, and is fixed in the axial direction by a caulking portion 53c formed by plastically deforming an end portion of the small diameter step portion 53b.

  A seal ring 56 is fitted and fixed to the outer end portion of the outer member 50, and the lip of the seal ring 56 is in sliding contact with the base portion 55 a of the wheel mounting flange 55. On the other hand, an encoder 57 is fitted and fixed to the outer peripheral surface of the inner end portion of the inner ring 54. The encoder 57 includes a support ring 58 having an L-shaped cross section, and an annular encoder body 59 attached and supported on the side surface of the support ring 58 over the entire circumference. In the encoder body 59, magnetic poles N and S are alternately magnetized at equal intervals in the circumferential direction.

  The inner end opening of the outer member 50 is closed by the cover 60. The cover 60 is formed in a petri dish from a nonmagnetic plate material such as a non-magnetic stainless steel plate, an aluminum alloy plate, or a high-functional resin, and has a circular closing plate portion 61 and an outer peripheral edge portion of the closing plate portion 61. And a cylindrical fitting portion 62 formed in the above.

  The side surface of the encoder main body 59 constituting the encoder 57 is disposed close to and opposed to the cover 60, and the detection unit 64 of the sensor 63 is adjacent to the side surface of the cover 60. The detection unit 64 and the encoder main body 59 are covered with each other. Proximity facing each other via 60. Thus, the presence of the cover 60 prevents water, iron powder, magnetic fragments, etc. from entering between the sensor 63 and the encoder 57, thereby preventing the sensor 63 and the encoder 57 from being damaged. It is possible to prevent the regular and periodic magnetic property changes of the main body 59 from being disturbed or deteriorated (see, for example, Patent Document 1).

JP 2000-249138 A

  However, such a conventional wheel bearing device with a rotational speed detection device has the following problems. First, the positioning of the cover 60 with respect to the outer member 50 is unstable. When the cover 60 is mounted, the bearing alone is transported, assembled to a vehicle, or mounted on wheels, the cover 60 is moved to a specified position by a stepping stone or the like. There is a risk of dislodging.

  Further, since the shape of the cover 60 is a simple U-shaped cross section, the rigidity is insufficient, and the cover 60 may be deformed by contact with a flying stone or the like, and may come into contact with the encoder main body 59. Furthermore, since the detection unit 64 of the sensor 63 faces the encoder 57 via the cover 60, the air gap may increase and the detection accuracy may decrease.

  SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and a wheel with a rotational speed detection device that improves positioning speed and improves the reliability of rotational speed detection while suppressing deformation by increasing the rigidity of the protective cover. An object of the present invention is to provide a bearing device for a vehicle.

  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 attachment for attaching a wheel to one end. The hub ring has a flange integrally 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 inner rolling surface facing the running surface is formed, and a double-row rolling element that is movably accommodated between the inner and outer members. And a magnetic encoder externally fitted to the inner ring, a seal is attached to the outer end of the outer member, and a protective cover is attached to the inner end of the outer member, The opening of the annular space formed by the outer member and the inner member is sealed. In the wheel bearing device with a speed detection device, the protective cover is formed in a cup shape by injection molding of a non-magnetic synthetic resin, and a cylindrical fitting portion fitted into the outer member, and the fitting A flange that protrudes radially outward from the flange and is in close contact with the inner end surface of the outer member, and extends radially inward from the flange, and has an inner end of the inner member. A metal core formed in a substantially L-shaped cross section by pressing from a steel plate is insert-molded into the fitting portion and the flange portion, and a rotational speed sensor is provided on the inner side surface of the bottom portion. A detection unit is brought close to and opposed to the magnetic encoder via a predetermined air gap, and a rib protrudes from at least one side surface of the bottom of the protective cover except for the opposed portion. .

  As described above, the magnetic encoder that is externally fitted to the inner ring is provided, the seal is attached to the outer end of the outer member, and the protective cover is attached to the inner end of the outer member. In a bearing device for a wheel with an inner ring rotation type rotational speed detection device in which an opening of an annular space formed by a member and an inner member is sealed, the protective cover is made of a nonmagnetic synthetic resin in a cup shape by injection molding A cylindrical fitting portion that is formed and fitted into the outer member, a flange portion that protrudes radially outward from the fitting portion, and that is in close contact with the inner end surface of the outer member; and It has a bottom portion that extends radially inward from the flange portion and closes the inner side end of the inner member, and is formed into a substantially L-shaped cross section by pressing from the steel plate at the fitting portion and the flange portion. The core bar is insert-molded and turned to the inner side of the bottom. The detection part of the speed sensor is brought close to and opposed to the magnetic encoder via a predetermined air gap, and a rib protrudes from at least one side surface of the bottom of the protective cover except for the opposed part. Therefore, it is possible to increase the rigidity of the protective cover, to prevent the flying stones from being deformed even if they collide with the protective cover, and to set the air gap small and to improve the detection accuracy.

  Preferably, if the core of the protective cover is made of a non-magnetic austenitic stainless steel plate as in the invention described in claim 2, it does not affect the flow path of magnetic flux with high accuracy. Speed can be detected.

  According to a third aspect of the present invention, the inner ring is provided in a state where a predetermined bearing preload is applied by a caulking portion formed by plastically deforming a small-diameter step portion of the hub wheel radially outward. If the stepped portion that is fixed in the axial direction with respect to the hub wheel and that bulges into the recess of the caulking portion is formed at the center of the bottom portion of the protective cover, the rigidity of the protective cover is further increased. It becomes high and can suppress deformation due to stepping stones.

  Preferably, as in the invention according to claim 4, if the stepped portion is formed in a substantially rectangular cross section along the shape of the recess of the crimped portion, a plurality of the stepped portions are formed on the bottom portion. Combined with the ribs, the rigidity of the protective cover is further increased, and deformation due to flying stones can be suppressed.

  Further, as in the invention described in claim 5, the detected surface of the magnetic encoder is arranged to protrude by a from the inner side end surface of the outer member, and the protruding amount a is the bottom of the protective cover. If the thickness is set to be smaller than the thickness t (a <t), the protective cover can be prevented from coming into contact with the magnetic encoder, and the air gap can be set small, so that the detection accuracy can be increased.

  Further, as in the invention described in claim 6, if a recess is formed in the bottom of the protective cover so as to be close to the magnetic encoder, and the detection unit is disposed in the concave, the rigidity of the protective cover is increased. In addition, the flying stone or the like can collide with the protective cover to prevent deformation, and the air gap can be set small, so that the detection accuracy can be increased.

  Further, as in the seventh aspect of the present invention, if the dent amount c of the concave portion is set smaller than the thickness b of the flange portion of the protective cover (c <b), the protective cover contacts the magnetic encoder. While preventing the contact, the rigidity of the protective cover can be maintained, the air gap can be set small, and the detection accuracy can be increased.

  Further, if the concave portion is formed in an eyebrow shape as in the invention described in claim 8, there is an error in the positioning accuracy in the circumferential direction of the protective cover with respect to the sensor while maintaining the rigidity of the protective cover. Is acceptable.

  Further, as in the invention described in claim 9, a plurality of the ribs may extend in the horizontal direction and be formed at substantially equal intervals.

  Further, as in the invention described in claim 10, a plurality of the ribs may extend in the vertical direction and may be formed at substantially equal intervals.

  Further, as in the invention described in claim 11, the ribs may be formed in a lattice shape.

  Moreover, like the invention of Claim 12, the said rib may be formed in the both sides | surfaces of the bottom part of the said protective cover, and the shape of each rib may differ.

  Further, as in a thirteenth aspect of the present invention, the ribs extend in the horizontal direction on one side surface of the bottom portion of the protective cover and are formed at a plurality of substantially equal intervals, and the ribs extend in the vertical direction on the other side surface. A plurality may be formed at equal intervals.

  Further, as in the invention described in claim 14, the ribs may extend in the horizontal direction on both side surfaces of the bottom portion of the protective cover, and a plurality of the ribs may be formed at substantially equal intervals with different phases.

  Further, as in the invention described in claim 15, if the rib is formed excluding a portion opposed to the magnetic encoder and a portion symmetrical to this portion, the protective cover becomes symmetrical. The workability when fitted to the outer member is improved.

  Further, if the rib is formed so as to surround the portion facing the magnetic encoder as in the invention described in claim 16, the rigidity of the protective cover can be further increased and the detection can be performed. It is possible to prevent a stepping stone or the like from directly colliding with the part.

  Further, as in the invention described in claim 17, a reinforcing material made of glass fiber may be added to the protective cover in an amount of 10 to 50 wt%, and as in the invention described in claim 18, the 5-50 wt% of a reinforcing material made of carbon fiber may be added to the protective cover. Thereby, intensity | strength and rigidity become high and durability can be improved over a long period of time.

  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. A hub ring 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 wheel, and facing the outer surface of the double row on the outer periphery. An inner member in which a double-row inner rolling surface is formed, a double-row rolling element housed between the inner member and the outer member so as to roll freely, and the inner ring A magnetic encoder externally fitted to the outer member, and a seal is attached to an outer end of the outer member, and a protective cover is attached to an inner end of the outer member. Speed at which the opening of the annular space formed by the inner member and the inner member is sealed In the wheel bearing device with a take-out device, the protective cover is formed into a cup shape by injection molding of a non-magnetic synthetic resin, and a cylindrical fitting portion fitted into the outer member, and the fitting portion And a flange that protrudes radially outward from the flange and adheres closely to the inner end surface of the outer member, and extends radially inward from the flange and closes the inner end of the inner member. A metal core having a substantially L-shaped cross section formed by pressing from a steel plate is insert-molded at the fitting portion and the flange portion, and a rotation speed sensor is detected on the inner side surface of the bottom portion. Since the parts are close to each other and faced to the magnetic encoder through a predetermined air gap, except for the part that is faced, a rib protrudes from at least one side surface of the bottom part of the protective cover. , Protective cover The rigidity, if with flying stones or the like can be prevented from being deformed even collide with the protective cover, it is possible to set small air gap, it is possible to improve the detection accuracy.

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. It is a principal part enlarged view of FIG. It is the front view seen from the protective cover of FIG. 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 the front view seen from the protective cover of FIG. It is a front view which shows the modification of FIG. It is a longitudinal cross-sectional view which shows 3rd 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 the front view seen from the protective cover of FIG. It is a longitudinal cross-sectional view which shows 4th Embodiment of the wheel bearing apparatus with a rotational speed detection apparatus which concerns on this invention. It is a single figure which shows the modification of the protective cover of FIG. 1, (a) is a front view, (b) is sectional drawing along the AA line of (a), (c) is (b). FIG. Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). Same as the above, (a) is a front view, (b) is a cross-sectional view taken along the line AA of (a), and (c) is a view as viewed from arrow B of (b). It is a principal part enlarged view which shows the conventional wheel bearing apparatus with a rotational speed detection apparatus.

  A vehicle body mounting flange to be attached to the knuckle on the outer periphery, an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a wheel mounting flange to mount a wheel on one end A hub wheel integrally formed and having one inner rolling surface opposed to the double-row outer rolling surface on the outer periphery, and a small-diameter step portion extending in the axial direction from the inner rolling surface, and the hub wheel An inner member formed of an inner ring that is press-fitted into the small-diameter step portion and formed with the other inner rolling surface opposite to the double row outer rolling surface, and the inner member and the outer member. A double row rolling element housed between the running surfaces so as to be freely rollable, and a magnetic encoder externally fitted to the inner ring, and a seal is attached to the outer end of the outer member, and A protective cover is attached to the inner side end of the outer member, and the outer member In the wheel bearing device with a rotational speed detection device in which the opening of the annular space formed by the inner member is sealed, by the crimping portion formed by plastically deforming the end portion of the small diameter step portion of the hub wheel, The inner ring is axially fixed to the hub ring in a state where a predetermined bearing preload is applied, and the protective cover is formed into a cup shape by injection molding of a non-magnetic synthetic resin. A cylindrical fitting portion fitted in the member, a flange portion that protrudes radially outward from the fitting portion, and is in close contact with the inner side end surface of the outer member, and a diameter from the flange portion A metal core that extends inward in the direction and has a bottom portion that closes an inner end of the inner member, and is formed into a substantially L-shaped cross section by pressing from a steel plate at the fitting portion and the flange portion. Is insert-molded, and the rotational speed is set on the inner side surface of the bottom. The detection part of the sensor is brought close to and opposed to the magnetic encoder through a predetermined air gap, and the ribs extending in the horizontal direction are substantially equal to the outer surface of the bottom of the protective cover except for the opposed part. A plurality are formed at intervals.

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 is an enlarged view of a main part of FIG. 1, and FIG. 3 is a protective cover of FIG. It is the front view seen from. 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 detecting device is for a driven wheel called a third generation, and is housed between the inner member 1, the outer member 2, and both the 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 and 2a are formed with a hardened layer having a surface hardness of 58 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. Moreover, the inner side rolling surface 4a which opposes one (outer side) of the said double row outer side rolling surface 2a, 2a and the small diameter step part 4b extended in an axial direction from this inner side rolling surface 4a are formed in outer periphery. Yes. 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. A seal 9 is attached to the outer opening of the annular space formed between the outer member 2 and the inner member 1, and a protective cover 10 is attached to the inner opening. This prevents leakage of the lubricating grease sealed inside the bearing and prevents rainwater and dust from entering the bearing from the outside.

  In addition, although the wheel bearing apparatus comprised by the double row angular contact ball bearing which used the ball for the rolling element 3 was illustrated here, it is not restricted to this, The double row tapered roller bearing which used the tapered roller for the rolling element 3 It may consist of. 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. It may be a first generation or second generation structure.

  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 58 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, improves not only the wear resistance of the base part 6b serving as the seal land part of the seal 9, but also loads the wheel mounting flange 6. Therefore, 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 is an integrated seal composed of a core metal 11 press-fitted into the inner periphery of the outer side end portion of the outer member 2 through a predetermined shimiro and a seal member 12 joined to the core metal 11. It is configured. 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. The intermediate lip 12b is slidably in contact with the squeeze, and the grease lip 12c is formed to be inclined toward the inner side of the bearing.

  A support ring 13 having an L-shaped cross section is fitted on the inner ring 5. 2, the support ring 13 includes a cylindrical portion 13a that is press-fitted into the outer diameter of the inner ring 5, and a vertical plate portion 13b that extends radially outward from the cylindrical portion 13a. A magnetic encoder 14 is integrally joined to the inner side surface of the plate portion 13b by vulcanization adhesion. In the magnetic encoder 14, magnetic powder such as ferrite is mixed in synthetic rubber, and magnetic poles N and S are magnetized alternately at equal pitches in the circumferential direction.

  The support ring 13 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). It is formed by processing. As a result, it is possible to prevent the support ring 13 from rusting and to increase the magnetic output of the magnetic encoder 14 to ensure stable detection accuracy.

  As shown in FIG. 1, the protective cover 10 attached to the inner side end of the outer member 2 includes a cylindrical fitting portion 10 a that is press-fitted into the inner periphery of the inner side end of the outer member 2, A flange portion 10b that protrudes radially outward from the fitting portion 10a and is in close contact with the inner side end surface 2c of the outer member 2, and extends radially inward from the flange portion 10b, and the inner member 1 And a bottom portion 10c that closes the end portion on the inner side. Moreover, the core metal 15 is insert-molded in the part of the fitting part 10a and the collar part 10b. The metal core 15 is formed in a substantially L-shaped cross section by press working from a non-magnetic austenitic stainless steel plate (JIS standard SUS304). Thereby, while being able to improve the airtightness of a fitting part, since this metal core 15 is a nonmagnetic body, the rigidity of the protective cover 10 can be made higher without affecting the flow path of magnetic flux. .

  The protective cover 10 is formed by injection molding from a synthetic resin material such as polyamide (PA) 66, PA6 / 12, and further, a reinforcing material such as GF (glass fiber) is added by 10 to 50 wt%. As a result, the sensing performance of the rotation speed sensor (not shown) is not adversely affected, the corrosion resistance is excellent, the strength and rigidity are increased, and the durability can be maintained over a long period of time. If the addition amount of GF is less than 10 wt%, the reinforcing effect is not exhibited, and if it exceeds 50 wt%, the fiber causes anisotropy and the density increases, and the dimensional stability during injection molding decreases. It is not preferable. Here, the cover main body 10 may be exemplified by synthetic resins such as polyphenylene sulfide (PPS), PPA (polyphthalamide), PBT (polybutylene terephthalate), etc., other than the above-described materials. Moreover, as a fibrous reinforcement, not only GF but CF (carbon fiber), an aramid fiber, a boron fiber, etc. can be illustrated other than this.

  In the present embodiment, as shown in an enlarged view in FIG. 2, the protective cover 10 is fitted into the end portion of the outer member 2 until the flange portion 10 b comes into close contact with the inner end surface 2 c of the outer member 2. Since it is press-fitted, the positioning accuracy of the protective cover 10 with respect to the outer member 2 can be increased, and highly reliable speed detection can be performed by accurate air gap adjustment.

  The detection unit 16 of the rotation speed sensor is close to the bottom 10c of the protective cover 10, and the detection unit 16 and the magnetic encoder 14 are arranged to face each other with a predetermined air gap (axial clearance) through the protective cover 10. Yes. In addition, since the protective cover 10 is 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 rotation speed detection by the sensor.

  Here, in the present embodiment, as shown in FIG. 3, a plurality of ribs 17 extending in the horizontal direction are integrally formed on the bottom portion 10 c of the protective cover 10. The ribs 17 are formed on the outer surface of the bottom portion 10c so as to protrude at substantially equal intervals, except for the detection unit 16 facing the magnetic encoder 14. The ribs 17 can increase the rigidity of the protective cover 10, prevent deformation of flying stones or the like even if they collide with the protective cover 10, can set the air gap small, and improve detection accuracy. be able to.

  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 a front view seen from the protective cover of FIG. Note that this embodiment is basically different from the above-described embodiment only in the configuration of the protective cover, and the other parts having the same parts or the same functions as those of the above-described embodiment are denoted by the same reference numerals. Detailed description thereof is omitted.

  A protective cover 18 is attached to the inner end of the outer member 2. This protective cover 18 is formed by injection molding from a synthetic resin material such as PA66, PA6 / 12, and further, a reinforcing material made of CF (carbon fiber) is added in an amount of 5 to 50 wt%. As a result, the sensing performance of the rotation speed sensor (not shown) is not adversely affected, the corrosion resistance is excellent, the strength and rigidity are increased, and the durability can be improved over a long period of time. If the addition amount of CF is less than 5 wt%, the reinforcing effect is not exhibited, and if it exceeds 50 wt%, the fiber causes anisotropy and the density increases, and the dimensional stability during injection molding decreases. It is not preferable.

  The protective cover 18 is formed with a cylindrical fitting portion 10a that is press-fitted into the inner periphery of the end portion of the outer member 2, and is formed to protrude radially outward from the fitting portion 10a. A flange portion 10b that is in close contact with the end surface 2c and a bottom portion 18a that extends radially inward from the flange portion 10b and closes the end portion on the inner side of the inner member 1 are provided. A detection unit of a sensor (not shown) is brought close to the bottom 18a of the protective cover 18, and the detection unit and the magnetic encoder 14 are arranged to face each other with a predetermined air gap through the protective cover 18.

  Here, in the present embodiment, as shown in FIG. 5, lattice-shaped ribs 19 and 20 are integrally formed on the bottom 18 a of the protective cover 18. The rib 19 is formed so as to protrude from the outer surface of the bottom portion 18a except for the detection unit 16 facing the magnetic encoder 14. On the other hand, the rib 20 protrudes from the inner surface of the bottom portion 18a and is integrally formed in a lattice shape. The ribs 19 and 20 can further increase the rigidity of the protective cover 18 and prevent the flying stones from being deformed even when they collide with the protective cover 18.

  FIG. 6 is a modification of the protective cover 18 of FIG. 5, in which a lattice-like rib 19 is integrally formed on the bottom 21 a of the protective cover 21 and the portion facing the magnetic encoder 14 (detection portion of the rotational speed sensor). A rib 22 is formed so as to protrude so as to surround a portion 16 adjacent to 16. As a result, the rigidity of the protective cover 21 can be further increased, and a flying stone or the like can be prevented from directly colliding with the detection unit 16.

  FIG. 7 is a longitudinal sectional view showing a third embodiment of a wheel bearing device with a rotational speed detection device according to the present invention, FIG. 8 is an enlarged view of a main part of FIG. 7, and FIG. 9 is a protective cover of FIG. It is the front view seen from. This embodiment is basically the same as the first embodiment described above (FIG. 1) except that the configuration of the protective cover is partially different, and the other parts have the same parts and the same functions as the previous embodiment. Parts are denoted by the same reference numerals, and detailed description thereof is omitted.

  A protective cover 23 is attached to the inner side end of the outer member 2. This protective cover 23 is formed by injection molding from a non-magnetic special ether-based synthetic resin material such as PA66, PA6, 12 or the like, and 5 to 50 wt% of a reinforcing material made of CF is added. As a result, the sensing performance of the rotation speed sensor (not shown) is not adversely affected, the corrosion resistance is excellent, the strength and rigidity are increased, and the durability can be maintained over a long period of time.

  The protective cover 23 is formed with a cylindrical fitting portion 10a that is press-fitted into the inner periphery of the end portion of the outer member 2, and is formed to project radially outward from the fitting portion 10a. A flange portion 10b that is in close contact with the end face 2c, a bottom portion 23a that extends radially inward from the flange portion 10b and closes the inner end portion of the inner member 1, and a step formed at the center of the bottom portion 23a. Part 23b. The rigidity of the protective cover 23 is increased by the stepped shape including the flange portion 10b, and deformation due to flying stones or the like can be suppressed.

  Here, as shown in an enlarged view in FIG. 8, an eyebrow-shaped recess 24 is formed on the bottom 23a of the protective cover 23 so as to be close to the magnetic encoder 14 by c. A detection portion of a rotation speed sensor (not shown) is brought close to the recess 24. Accordingly, it is possible to set the air gap small while maintaining the rigidity of the protective cover 23, and tolerate even if there is an error in the positioning accuracy of the protective cover 23 in the circumferential direction with respect to the rotational speed sensor. Can do.

  Further, the detected surface of the magnetic encoder 14 is disposed so as to protrude from the inner end surface 2c of the outer member 2 by a. The protruding amount a is set smaller than the thickness t of the bottom 23a of the protective cover 23 (a <t), and the recessed amount c of the recessed portion 24 is smaller than the thickness b of the flange 10b of the protective cover 23. (C <b). Thereby, while preventing the protective cover 23 from coming into contact with the magnetic encoder 14, the rigidity of the protective cover 23 can be maintained, the air gap can be set small, and the detection accuracy can be increased. .

  In the present embodiment, as in the above-described embodiment, as shown in FIG. 9, a plurality of ribs 17 extending in the horizontal direction are integrally formed on the bottom 23 a of the protective cover 23. The ribs 17 are formed on the outer surface of the bottom 23a so as to protrude at substantially equal intervals, except for the recess 24 facing the magnetic encoder 14. The ribs 17 can increase the rigidity of the protective cover 23 and prevent the flying stones from deforming even if they collide with the protective cover 23.

  FIG. 10 is a longitudinal sectional view showing a fourth embodiment of the wheel bearing device with a rotational speed detection device according to the present invention. This embodiment is basically the same as the above-described third embodiment (FIG. 7) except that the configuration of the protective cover is partially different, and the other parts have the same parts and the same functions as the above-described embodiment. Parts are denoted by the same reference numerals, and detailed description thereof is omitted.

  A protective cover 25 is attached to the inner side end of the outer member 2. The protective cover 25 is formed by injection molding from a non-magnetic special ether-based synthetic resin material such as PA66, PA6 / 12, and further, a reinforcing material made of CF is added in an amount of 5 to 50 wt%. As a result, the sensing performance of the rotation speed sensor (not shown) is not adversely affected, the corrosion resistance is excellent, the strength and rigidity are increased, and the durability can be maintained over a long period of time.

  The protective cover 25 is formed with a cylindrical fitting portion 10 a that is press-fitted into the inner periphery of the end portion of the outer member 2, and protrudes radially outward from the fitting portion 10 a, and is formed on the inner side of the outer member 2. A flange portion 10b that is in close contact with the end face 2c, a bottom portion 23a that extends radially inward from the flange portion 10b and closes the inner end portion of the inner member 1, and a step formed at the center of the bottom portion 23a. Part 25a. The stepped portion 25a bulges toward the outer side along the inner wall shape of the recess 7a of the caulking portion 7, and is formed in a substantially rectangular cross section. Thereby, combined with the plurality of ribs 17 formed on the bottom 23a, the rigidity of the protective cover 25 is further increased, and deformation due to flying stones or the like can be suppressed.

  11 to 22 show a modification of the protective cover. In the protective cover 26 shown in FIG. 11, a plurality of ribs 17 extending in the horizontal direction are integrally formed on the bottom 26a. The ribs 17 are formed so as to protrude at substantially equal intervals only on the inner surface of the bottom portion 26a except for the detection portion 16 facing the magnetic encoder 14 and the road surface side portion of the bottom portion 26a symmetrical to the detection portion 16. ing. Thereby, the protective cover 26 becomes symmetrical, and the workability when fitted to the outer member 2 is improved.

  In the protective cover 27 shown in FIG. 12, a plurality of ribs 17 extending in the horizontal direction are integrally formed on both side surfaces of the bottom portion 27a. The ribs 17 are formed so as to protrude at substantially equal intervals in a state where the phases are different between the outer surface and the inner surface except for the detection unit 16 facing the magnetic encoder 14.

  In the protective cover 28 shown in FIG. 13, a plurality of ribs 17 extending in the horizontal direction on the outer surface of the bottom portion 28a and a plurality of ribs 29 extending in the vertical direction on the inner surface are integrally formed. The ribs 17 and 29 are formed so as to protrude at substantially equal intervals except for the detection unit 16 facing the magnetic encoder 14. Thereby, the rigidity of the protective cover 28 further increases.

  In the protective cover 30 shown in FIG. 14, a plurality of ribs 17 extending in the horizontal direction on the outer surface of the bottom portion 30 a and a grid-like rib 20 on the inner surface are integrally formed. The ribs 17 and 20 are formed on the bottom portion 30a so as to protrude at substantially equal intervals except for the detection unit 16 facing the magnetic encoder 14.

  The protective cover 31 shown in FIG. 15 is integrally formed with a plurality of ribs 29 extending in the vertical direction on the outer surface of the bottom 31a. Further, the protective cover 32 shown in FIG. 16 is integrally formed with a plurality of ribs 29 extending in the vertical direction on the inner surface of the bottom portion 32a. Moreover, the protective cover 33 shown in FIG. 17 is integrally formed with a plurality of ribs 29 extending in the vertical direction on the outer side surface of the bottom 33a and ribs 17 extending in the horizontal direction on the inner side surface. The outer side ribs 29 are formed so as to protrude at substantially equal intervals except for the detection unit 16 facing the magnetic encoder 14, while the inner side ribs 17 are symmetrical with the detection unit 16. Except for the portion of the bottom 33a on the road surface side, the bottom portion 33a is formed to protrude at substantially equal intervals.

  In the protective cover 34 shown in FIG. 18, a plurality of ribs 29 extending in the vertical direction are integrally formed on both side surfaces of the bottom 34a. The ribs 29 are formed so as to protrude at substantially equal intervals in a state where the phase is different between the outer surface and the inner surface except for the detection unit 16 facing the magnetic encoder 14. Further, in the protective cover 35 shown in FIG. 19, a plurality of ribs 29 extending in the vertical direction are formed on the outer surface of the bottom portion 35a, and the lattice-like ribs 20 are formed on the inner surface. Further, in the protective cover 36 shown in FIG. 20, the lattice-like ribs 20 are integrally formed only on the inner surface of the bottom portion 36a.

  The protective cover 37 shown in FIG. 21 has a grid-like rib 19 formed on the outer surface of the bottom portion 37a, and a plurality of ribs 17 extending in the horizontal direction on the inner surface. The ribs 17 are formed so as to protrude at substantially equal intervals except for the detection unit 16 facing the magnetic encoder 14 and the road surface side portion of the bottom 37a symmetrical to the detection unit 16. Further, the protective cover 38 shown in FIG. 22 has a lattice-like rib 19 formed on the outer surface of the bottom 38a, and a plurality of ribs 29 extending in the vertical direction on the inner surface.

  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 detection device according to the present invention can be applied to a wheel bearing device on the driven wheel side of the first to third generation structure of the inner ring rotation type.

DESCRIPTION OF SYMBOLS 1 Inner member 2 Outer member 2a Outer rolling surface 2b Car body mounting flange 2c End side of inner side of outer member 3 Rolling element 4 Hub wheel 4a, 5a Inner rolling surface 4b Small diameter step portion 5 Inner ring 6 Wheel mounting flange 6a Hub bolt 6b Inner side base 7 Clamping portion 7a Recess 8 Retainer 9 Outer side seal 10, 18, 21, 23, 25, 26, 27, 28, 30-38 Protective cover 10a Fitting portion 10b Gutter portion 10c , 18a, 21a, 23a, 26a, 27a, 28a, 30a-38a Bottom 11, 15 Core 12 Seal member 12a Side lip 12b Intermediate lip 12c Grease lip 13 Support ring 13a Cylindrical part 13b Standing plate part 14 Magnetic encoder 16 Detection part 17, 19, 20, 22, 29 Ribs 23b, 25a Stepped portion 24 Recessed portion 50 Outer member 50a Outer rolling surface 50b Mounting flange 51 Inner member 52 Ball 53 Hub wheel 53a, 54a Inner rolling surface 53b Small diameter step portion 53c Clamping portion 54 Inner ring 55 Wheel mounting flange 55a Base 56 Seal ring 57 Encoder 58 Support ring 59 Encoder body 60 Cover 61 Closing plate Part 62 fitting part 63 sensor 64 detecting part 65 knuckle 66 screw a protrusion amount b from end face of the outer member of the detected surface of the magnetic encoder b thickness of the protective cover collar c concave part t amount of the protective cover bottom part Thickness

Claims (18)

An outer member in which a double row outer rolling surface is 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 magnetic encoder fitted on the inner ring,
An annular space is formed by the outer member and the inner member having a seal attached to the outer end portion of the outer member and a protective cover attached to the inner end portion of the outer member. In the wheel bearing device with a rotational speed detection device in which the opening of
The protective cover is formed of a non-magnetic synthetic resin in a cup shape by injection molding, and is formed by a cylindrical fitting portion fitted into the outer member, and protruding radially outward from the fitting portion. A flange portion closely contacting the inner side end surface of the outer member, and a bottom portion extending radially inward from the flange portion and closing the inner side end portion of the inner member,
A cored bar formed in a substantially L-shaped cross section by press working from a steel plate at the part of the fitting portion and the flange portion is insert-molded,
The detection part of the rotational speed sensor is brought close to the inner side surface of the bottom part, and is opposed to the magnetic encoder through a predetermined air gap,
A wheel bearing device with a rotational speed detecting device, wherein a rib protrudes from at least one side surface of the bottom portion of the protective cover, excluding the facing portion.   The wheel bearing device with a rotation speed detecting device according to claim 1, wherein the core metal of the protective cover is formed of a non-magnetic austenitic stainless steel plate.   The inner ring is fixed to the hub ring in the axial direction with a predetermined bearing preload by a caulking portion formed by plastically deforming a small-diameter step portion of the hub ring radially outward. The wheel bearing device with a rotational speed detection device according to claim 1, wherein a stepped portion that bulges into a recess of the caulking portion is formed at the center of the bottom portion of the protective cover.   The wheel bearing device with a rotational speed detection device according to claim 3, wherein the stepped portion is formed in a substantially rectangular cross section along the shape of the recess of the caulking portion.   The detected surface of the magnetic encoder is disposed so as to protrude from the inner end surface of the outer member by a, and the protruding amount a is set smaller than the thickness t of the bottom of the protective cover (a <t). The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 4.   The wheel bearing device with a rotation speed detection device according to any one of claims 1 to 5, wherein a concave portion is formed in the bottom portion of the protective cover so as to be close to the magnetic encoder, and the detection portion is disposed in the concave portion.   The wheel bearing device with a rotational speed detecting device according to claim 6, wherein a concave amount c of the concave portion is set smaller than a thickness b of the flange portion of the protective cover (c <b).   The wheel bearing device with a rotation speed detecting device according to claim 6 or 7, wherein the concave portion is formed in an eyebrow shape.   The wheel bearing device with a rotation speed detection device according to claim 1, wherein a plurality of the ribs extend in a horizontal direction and are formed at substantially equal intervals.   The wheel bearing device with a rotational speed detection device according to claim 1, wherein a plurality of the ribs extend in a vertical direction and are formed at substantially equal intervals.   The wheel bearing device with a rotation speed detection device according to claim 1, wherein the rib is formed in a lattice shape.   The wheel bearing device with a rotation speed detecting device according to claim 1, wherein the ribs are formed on both side surfaces of the bottom portion of the protective cover, and the shapes of the ribs are different.   The ribs extending in the horizontal direction on one side surface of the bottom portion of the protective cover and formed in a plurality at substantially equal intervals, and a plurality of ribs extending in the vertical direction on the other side surface and formed in a plurality at substantially equal intervals. Wheel bearing device with a rotation speed detection device.   The wheel bearing device with a rotation speed detection device according to claim 1, wherein the ribs extend in the horizontal direction on both side surfaces of the bottom portion of the protective cover, and a plurality of the ribs have different phases and are formed at substantially equal intervals.   The wheel bearing device with a rotational speed detection device according to claim 1, wherein the rib is formed excluding a portion facing the magnetic encoder and a portion symmetrical to the portion.   The wheel bearing device with a rotation speed detection device according to claim 1, wherein a rib protrudes so as to surround a portion facing the magnetic encoder.   The wheel bearing device with a rotational speed detection device according to any one of claims 1 to 16, wherein a reinforcing material made of glass fiber is added to the protective cover in an amount of 10 to 50 wt%.   The wheel bearing device with a rotation speed detecting device according to any one of claims 1 to 16, wherein a reinforcing material made of carbon fiber is added to the protective cover in an amount of 5 to 50 wt%.

Images