JP2006064180A - Vehicular rolling bearing unit with encoder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a structure capable of attaining high sealability, miniaturization and weight reduction, and accommodating a change of an installation position of an encoder and/or a sensor as required, thus contributing to improvement of design flexibility. <P>SOLUTION: An encoder 7a of a permanent magnet is attached to an outer surface of a circular ring part 14 of a slinger 8a constituting a combined seal ring 6a. An outer surface of the encoder 7a is covered with a cover plate 19 of a non-magnetic material. This cover plate 19 prevents adhesion of foreign matter and damage to the encoder 7a. A seal lip 16b is slidably provided on an inner surface of the circular ring part 14 of the slinger 8a. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The rolling bearing unit with an encoder for an automobile according to the present invention supports the wheel of the automobile so as to be rotatable with respect to the suspension device and detects the rotational speed of the wheel supported by the rolling bearing unit.

  In order to detect the rotational speed of this wheel in order to support the wheel of the automobile so that it can rotate freely with respect to the suspension system and to control the anti-lock brake system (ABS) and traction control system (TCS), various structures have been conventionally used. A rolling bearing unit with an encoder is known. Moreover, as an encoder incorporated in such a roller bearing unit with an encoder, permanent magnets such as rubber magnets and plastic magnets, in which S poles and N poles are alternately arranged at equal intervals in the circumferential direction, are used. Some are used because they can stabilize the output of the sensor regardless of the rotational speed of the wheels. Furthermore, when using such an encoder made of a permanent magnet, a structure in which the encoder is supported and fixed to a support element made of a non-magnetic material and separated from the surrounding space by this support element is also described in Patent Document 1. Like, it is known from the past.

  FIG. 8 shows a rolling bearing unit with an encoder described in Patent Document 1. This rolling bearing unit with an encoder, like a general rolling bearing unit, has an inner ring raceway 1 on its outer peripheral surface, and an inner ring 2 that rotates together with the wheels during use, and an outer ring raceway 3 (see FIG. 8). (Refer to FIGS. 1 to 7), and can be freely rolled between the outer ring raceway 3 and the inner ring raceway 1 which are not rotated while being supported by the suspension device in use. And a plurality of rolling elements 5 provided. An encoder 7 is incorporated in a combination seal ring 6 that closes between the outer peripheral surface of the end portion of the inner ring 2 and the inner peripheral surface of the end portion of the outer ring 4.

  The combination seal ring 6 includes a slinger 8 made of a nonmagnetic metal plate that is fitted and fixed to the outer peripheral surface of the end portion of the inner ring 2, and a seal ring 9 that is fitted and fixed to the inner peripheral surface of the outer ring 4. . Further, the seal ring 9 is provided with a seal lip 11 made of an elastic material all around the inner periphery of an annular cored bar 10 having an L-shaped cross section. The inner peripheral edge of the seal lip 11 is pressed against the outer peripheral surface of the cylindrical portion 12 constituting the slinger 8 by the elasticity of the garter spring 13 fitted on the seal lip 11. On the other hand, the encoder 7 is attached to the entire inner surface facing the seal ring 9 on both side surfaces in the axial direction of the annular portion 14 constituting the slinger 8. The encoder 7 is a permanent magnet, and S poles and N poles are alternately arranged on the side surfaces in the axial direction.

  The above-mentioned rolling bearing unit with an encoder supports and fixes a wheel to an end of an axle through which the inner ring 2 is inserted, and supports and fixes the outer ring 4 to a suspension device. Is supported rotatably. Further, the detection portion of the sensor 15 supported by the suspension device is opposed to the side surface of the encoder 7. When the inner ring 2 rotates together with the wheel in this state, the encoder 7 rotates together with the slinger 8 and the output of the sensor 15 facing the side surface of the encoder 7 changes. The frequency at which the output of the sensor 15 changes is proportional to the rotational speed of the wheel. Therefore, if the output signal of the sensor 15 is input to a controller (not shown), the rotational speed of the wheel can be obtained and the ABS and TCS can be controlled appropriately.

  In the case of a conventional rolling bearing unit with an encoder configured and operated as described above, the encoder 7 made of permanent magnet is covered with the slinger 8 made of nonmagnetic metal plate and is not exposed to the external space. For this reason, the magnetic powder floating in this external space is difficult to adhere to the encoder 7, and even if it adheres, the magnetic powder is swung away with the rotation of the slinger 8, and the magnetic powder is directly applied to the encoder 7 and the sensor. It is hard to remain between 15 detection units. For this reason, it is possible to ensure the accuracy of rotation speed detection by the sensor 15. In addition, since foreign matter such as pebbles does not directly hit the encoder 7, it is possible to prevent the encoder 7 from being damaged such as cracking or chipping. Reliability can be ensured.

  In the case of a conventionally known rolling bearing unit with an encoder as described above, the degree of freedom in design is small, for example, improved sealing performance of a combination seal ring, miniaturization and weight reduction, and change of encoder and sensor mounting positions. It cannot correspond to etc.

US Pat. No. 5,575,568

  In view of the circumstances as described above, the present invention realizes a rolling bearing unit with an encoder that can cope with improvement in sealing performance of a combined seal ring, reduction in size and weight, change in the mounting position of an encoder and a sensor, and the like as necessary. Invented accordingly.

Among the rolling bearing units with an encoder of the present invention, the rolling bearing unit with an encoder according to claim 1 includes a stationary ring, a rotating ring, a plurality of rolling elements, a slinger, a seal ring, an encoder, And a cover layer.
Among these, the stationary wheel has a stationary-side track on the stationary-side peripheral surface, and does not rotate while being supported by the suspension device during use. The rotating wheel has a rotating side track on the rotating side peripheral surface facing the stationary side peripheral surface, and rotates together with the wheel when in use. The plurality of rolling elements are provided between the rotating side track and the stationary side track so as to freely roll. The slinger has an L-shaped cross section including a cylindrical portion and an annular portion bent in a radial direction from an edge of the cylindrical portion, and the cylindrical portion is fitted to the end portion of the rotating side circumferential surface. Thus, the rotating wheel is supported and fixed concentrically with the rotating wheel. The seal ring is formed by reinforcing an annular elastic member having a plurality of seal lips with an annular cored bar, and the cored bar is fitted and fixed to the end of the stationary peripheral surface. The leading edge of each seal lip is brought into sliding contact with the peripheral surface of the cylindrical portion and the one side surface of the annular portion constituting the slinger. The encoder is fixed concentrically with the rotating wheel over the entire circumference by closely contacting one side surface in the axial direction to the other side surface of the circular ring portion constituting the slinger. S poles and N poles are alternately arranged on the other side surface in the circumferential direction. Further, the cover layer covers at least the other axial side surface of the encoder surface, and is made of a non-magnetic material.

  A rolling bearing unit with an encoder according to a second aspect includes an inner ring, an outer ring, a plurality of rolling elements, an encoder, and a cover layer. Among these, the inner ring has an inner ring raceway on the outer peripheral surface, and does not rotate while being supported by the suspension device during use. The outer ring has an outer ring raceway on the inner peripheral surface, and rotates with the wheel when in use. The plurality of rolling elements are provided between the outer ring raceway and the inner ring raceway so as to roll freely. The encoder is fitted and fixed to the outer peripheral surface of the outer ring, and the S pole and the N pole are alternately arranged on the outer peripheral surface in the circumferential direction. Further, the cover layer covers at least the outer peripheral surface of the surface of the encoder, and is made of a nonmagnetic material.

According to the rolling bearing unit with an encoder of the present invention configured as described above, an encoder with an encoder that can cope with improvement in sealing performance of the combined seal ring, reduction in size and weight, change in the mounting position of the encoder and sensor, etc., as necessary. A rolling bearing unit can be realized, which can contribute to the improvement of the degree of freedom in automobile design.
First, according to the rolling bearing unit with an encoder described in claim 1, since the encoder is provided on the other side surface of the annular portion constituting the slinger, the seal is provided without particularly increasing the diameter of the annular portion. A part of the plurality of seal lips constituting the ring can be brought into sliding contact with one side surface of the ring portion. Therefore, it is possible to improve the sealing performance of the combined seal ring composed of the slinger and the seal ring without particularly increasing the size of the combined seal ring. According to the rolling bearing unit with an encoder described in claim 2, the encoder is fitted and fixed to the outer peripheral surface of the outer ring rotating around the inner ring, and the sensor detection portion is opposed to the outer peripheral surface of the encoder in the radial direction. With this structure, the encoder made of permanent magnets can be protected.

  FIG. 1 shows a first embodiment of the present invention corresponding to claim 1. The rolling bearing unit with an encoder of this embodiment has an inner ring raceway 1 on its outer peripheral surface, and an inner ring 2 that rotates together with the wheel when in use, and an outer ring raceway 3 on its inner peripheral face, as in a general rolling bearing unit. And a plurality of rolling elements 5 provided between the outer ring raceway 3 and the inner ring raceway 1 so as to roll freely. An encoder 7a is incorporated in a combination seal ring 6a that closes the gap between the outer peripheral surface of the end portion of the inner ring 2 and the inner peripheral surface of the end portion of the outer ring 4a.

  Of these, the combination seal ring 6a is provided on a slinger 8a made of a ferromagnetic metal plate such as a ferromagnetic stainless steel plate or a steel plate, which is fitted and fixed to the outer peripheral surface of the end portion of the inner ring 2, and an inner peripheral surface of the outer ring 4a. It comprises a seal ring 9a that is fitted and fixed internally. Further, the seal ring 9a is provided with an elastic material 17 having a plurality of (two in the illustrated example) seal lips 16a and 16b on the inner peripheral edge of an annular cored bar 10 having an L-shaped cross section on the entire circumference. They are attached. Of these two seal lips 16a and 16b, the tip edge (inner peripheral edge) of the seal lip 16a projecting radially inward is formed on the outer peripheral surface of the cylindrical portion 12 constituting the slinger 8a and also on the side in the axial direction. The leading edge of the projecting seal lip 16b is placed on the inner surface of the annular ring portion 14 constituting the slinger 8a (the side surface on the space 18 side where the rolling elements 5 are installed) due to the elasticity of the seal lips 16a and 16b. It is made to contact elastically. Accordingly, the inside and outside of the space 18 are double-sealed by the two sealing lips 16a and 16b, so that the grease sealed in the space 18 leaks to the outside, and rainwater or the like existing in the outside space It is possible to effectively prevent foreign matter from entering the space 18.

  On the other hand, the encoder 7a is attached to the outer surface of the annular portion 14 constituting the slinger 8a over the entire circumference. The encoder 7a is a permanent magnet such as a rubber magnet, a plastic magnet, or a ferrite magnet, and is magnetized in the axial direction (left-right direction in FIG. 1). The magnetization direction is changed alternately and at equal intervals in the circumferential direction. Accordingly, the south pole and the north pole are alternately arranged in the circumferential direction on the outer side surface (side surface opposite to the space 18) of the encoder 7a. Further, a cover plate 19 is formed on the outer surface of the encoder 7a by bonding or the like by using a nonmagnetic material such as synthetic resin, aluminum, or nonmagnetic stainless steel so that the inner and outer diameters are in the shape of a ring with the same dimensions as the encoder 7a. Thus, the cover layer described in claim 1 is formed.

  The rolling bearing unit with an encoder of the present embodiment as described above is inserted through the inner ring 2 (the inner ring 2 is fitted and fixed to its end), and a wheel (not shown) is supported and fixed to the end of an axle (not shown). At the same time, the outer ring 4a is supported and fixed in the mounting hole 21 of the knuckle 20 constituting the suspension device. With this configuration, the wheel is rotatably supported with respect to the suspension device. The detecting portion of the sensor 15a inserted through the insertion hole 22 provided in the knuckle 20 from the outer diameter side to the inner diameter side is opposed to the outer surface of the encoder 7a via the cover plate 19. In this state, the sensor 15 a is fixed to the knuckle 20 by connecting the mounting flange 23 provided at the base end thereof to the outer peripheral surface of the knuckle 20 with a screw 24.

  When the inner ring 2 is rotated together with the wheel in the state where the constituent members are assembled in this manner, the encoder 7a rotates together with the slinger 8a, and the output of the sensor 15a facing the outer surface of the encoder 7a changes. . The frequency at which the output of the sensor 15a changes is proportional to the rotational speed of the wheel. Therefore, if the output signal of the sensor 15a is input to a controller (not shown), the rotational speed of the wheel can be obtained and the ABS and TCS can be controlled appropriately.

  Further, in the case of the rolling bearing unit with an encoder of this embodiment configured and acting as described above, the encoder 7a made of permanent magnet is covered with the cover plate 19 made of nonmagnetic plate and is not exposed to the external space. . Accordingly, the magnetic powder floating in the external space is unlikely to adhere to the outer surface of the encoder 7a, and even if temporarily attached, the magnetic powder is swung away around as the cover plate 19 rotates with the slinger 8a. The magnetic powder hardly remains between the outer surface of the encoder 7a and the detection portion of the sensor 15a. Therefore, it is possible to ensure the accuracy of rotation speed detection by the sensor 15a. Further, since foreign matter such as pebbles does not directly collide with the encoder 7a, the encoder 7a is prevented from being damaged such as cracking or chipping, and a rotational speed detecting device including the encoder 7a is provided. Reliability can be ensured.

  Further, in the case of the rolling bearing unit with an encoder of the present embodiment, the encoder 7a is provided on the outer surface of the annular portion 14 constituting the slinger 8a, so that the diameter of the annular portion 14 is particularly increased. Even if not, the tip edge of the seal lip 16b protruding in the axial direction of the plurality of seal lips 16a, 16b constituting the seal ring 9a is brought into sliding contact with the inner side surface of the annular portion 14. I can do things. Therefore, the sealing performance of the combined seal ring 6a composed of the slinger 8a and the seal ring 9a can be improved without particularly increasing the size (increasing diameter) of the combined seal ring 6a.

  On the other hand, in the case of the conventional structure shown in FIG. 8, when the number of seal lips is increased to improve the sealing performance, the encoder 7 is moved radially outward of the annular portion 14. Therefore, it is necessary to increase the outer diameter of the circular ring portion 14, and it is necessary to increase the size of the combined seal ring 6. In the case of the above-described conventional structure, the sealing performance is ensured by providing the garter spring 13, but not only the assembly work becomes troublesome, but also the rotational resistance of the rolling bearing unit increases. In the case of the rolling bearing unit with an encoder of the present embodiment, the disadvantages of such a conventional structure can be eliminated.

  Next, FIG. 2 shows a second embodiment of the present invention, which also corresponds to claim 1. In the case of this embodiment, a cover layer 25 made of a nonmagnetic material such as rubber or synthetic resin is molded on the encoder 7a attached to the outer surface of the slinger 8a constituting the combination seal ring 6a, and the encoder 7a The outer side surface and both inner and outer peripheral edges are covered. Since the configuration and operation of the other parts are the same as in the case of the above-described first embodiment, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  Next, FIG. 3 shows Embodiment 3 of the present invention, which also corresponds to claim 1. In the case of this embodiment, the entire outer ring surface of the inner ring 2 is formed in an annular shape with an L-shaped cross section by a nonmagnetic plate such as a synthetic resin, aluminum, nonmagnetic stainless steel, or a copper alloy such as brass. The cover plate 26 is fitted and fixed. Then, the cylindrical portion 12 of the slinger 8a constituting the combination seal ring 6a is externally fixed to the cylindrical portion 27 constituting the cover plate 26, and the slinger 8a is secured by the annular portion 28 constituting the cover plate 26. The outer surface of the encoder 7a attached to the outer surface of the circular ring portion 14 is covered. Since the configuration and operation of the other parts are the same as those in the first embodiment and the second embodiment described above, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  Next, FIG. 4 shows Embodiment 4 of the present invention, which also corresponds to claim 1. In the case of this embodiment, as in the case of the above-described embodiment 2, the outer peripheral surface of the end portion of the inner ring 2 is cross-sectioned by a nonmagnetic plate such as a synthetic resin, aluminum, nonmagnetic stainless steel, or a copper alloy such as brass. An L-shaped cover plate 26a, which is formed in an annular shape as a whole, is externally fitted and fixed. However, in the case of the present embodiment, the cylindrical portion 27a that constitutes the cover plate 26a is located outside the inner ring 2 at a portion closer to the end in the axial direction than the cylindrical portion 12 of the slinger 8a that constitutes the combined seal ring 6a. It is fitted and fixed. The outer surface of the encoder 7a attached to the outer surface of the annular portion 14 constituting the slinger 8a is covered by the annular portion 28 constituting the cover plate 26a. Since the configuration and operation of the other parts are the same as in the case of the above-described third embodiment, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  Next, FIG. 5 shows Embodiment 5 of the present invention corresponding to claim 2. In the case of the present embodiment, a cylindrical encoder 7 b is externally fitted and fixed to the outer peripheral surface of the outer ring 4 via a holding cylinder 29. Of these, the holding cylinder 29 is formed in a cylindrical shape by a ferromagnetic metal plate such as magnetic stainless steel or mild steel, and is fitted and fixed to the outer peripheral surface of the end portion of the outer ring 4 by an interference fit. The encoder 7b is a permanent magnet that is slightly elastically deformable, such as a rubber magnet or a plastic magnet, and is magnetized in the radial direction. The magnetization direction is changed alternately at equal intervals over the circumferential direction. Therefore, on the outer peripheral surface of the encoder 7b, the S pole and the N pole are alternately arranged at equal intervals over the circumferential direction. Furthermore, a cover layer that covers the outer peripheral surface of the encoder 7b is configured by fitting a cover cylinder 30 formed in a cylindrical shape with a non-magnetic material such as rubber, synthetic resin, aluminum, or brass onto the encoder 7b. Yes.

  Further, a core metal 10a constituting the seal ring 9b is fitted and fixed to the outer peripheral surface of the end portion of the inner ring 2, and the outer peripheral edge of the seal lip 11a attached to the outer peripheral edge of the core metal 10a over the entire circumference. Is brought into contact with the inner peripheral surface of the end portion of the outer ring 4 over the entire circumference. The assembled state of the seal ring 9b may be reversed inside and outside in the radial direction from the illustrated example. Further, in the assembled state to the vehicle, the detection portion provided on the front end surface of the sensor 15b supported by the suspension device is opposed to the outer peripheral surface of the encoder 7b.

  According to the rolling bearing unit with an encoder of this embodiment configured as described above and used in a state assembled to a vehicle, the encoder 7b is fitted and fixed to the outer peripheral surface of the outer ring 4 that rotates around the inner ring 2. With the structure in which the detection part of the sensor 15b is opposed to the outer peripheral surface of the encoder 7b in the radial direction, the permanent magnet encoder 7b can be protected in the same manner as in the first to fourth embodiments.

  Next, FIG. 6 shows Embodiment 6 of the present invention, which also corresponds to claim 2. In the case of the present embodiment, a cover layer 25a made of a non-magnetic material such as rubber or synthetic resin is molded on the encoder 7c fitted and fixed to the outer peripheral surface of the end portion of the outer ring 4, and the outer peripheral surface of the encoder 7c and Covers both axial edges. Since the configuration and operation of the other parts are the same as in the case of the above-described fifth embodiment, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  Next, FIG. 7 shows Embodiment 7 of the present invention, which also corresponds to claim 2. In the case of the present embodiment, as in the case of the above-described fifth embodiment, a cylindrical encoder 7 b is externally fitted and fixed to the outer peripheral surface of the end portion of the outer ring 4 via a holding cylinder 29. A base end of a cover cylinder 30a formed in a substantially cylindrical shape with a cross-sectional crank shape on a portion adjacent to the encoder 7b on the outer peripheral surface of the outer ring 4 and made of a non-magnetic material such as rubber, synthetic resin, aluminum, or brass. A cover layer that covers the outer peripheral surface of the encoder 7b is formed by externally fitting the portion. Since the configuration and operation of the other parts are the same as in the case of the above-described fifth embodiment, the same parts are denoted by the same reference numerals, and redundant description is omitted.

The fragmentary sectional view which shows Example 1 of this invention. The fragmentary sectional view which shows the same Example 2. FIG. The fragmentary sectional view which shows the same Example 3. FIG. The fragmentary sectional view which shows the same Example 4. FIG. The fragmentary sectional view which shows the same Example 5. FIG. The fragmentary sectional view which shows the Example 6. FIG. The fragmentary sectional view which shows the Example 7. FIG. The fragmentary sectional view which shows one example of the conventional structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner ring raceway 2 Inner ring 3 Outer ring raceway 4, 4a Outer ring 5 Rolling element 6, 6a Combination seal ring 7, 7a, 7b, 7c Encoder 8, 8a Slinger 9, 9a, 9b Seal ring 10, 10a Core metal 11, 11a Seal lip 12 cylindrical portion 13 garter spring 14 annular portion 15, 15a, 15b sensor 16a, 16b seal lip 17 elastic material 18 space 19 cover plate 20 knuckle 21 mounting hole 22 insertion hole 23 mounting flange 24 screw 25, 25a cover 26, 26a cover Plate 27, 27a Cylindrical part 28 Annular part 29 Holding cylinder 30, 30a Cover cylinder

Claims (2)

  It has a stationary side track on the stationary side circumferential surface and has a stationary side wheel that does not rotate while being supported by a suspension device in use, and a rotating side track on the rotational side circumferential surface that faces the stationary side circumferential surface. A rotating wheel that rotates together with the wheel, a plurality of rolling elements provided between the rotating-side track and the stationary-side track, and a fixed support concentrically with the rotating wheel on a part of the rotating wheel. The L-shaped cross-section includes a cylindrical portion and an annular portion bent in the radial direction from an edge of the cylindrical portion, and the rotation is achieved by fitting the cylindrical portion of the cylindrical portion to the end of the rotating side peripheral surface. A state in which a slinger fixed to a ring and an annular elastic material having a plurality of seal lips are reinforced by an annular cored bar, and this cored bar is fitted and fixed to the end of the stationary peripheral surface The peripheral edge of the cylindrical part and the annular part constituting the slinger The seal ring slidably contacted on one side and the other side of the circular ring portion constituting the slinger were brought into close contact with the one side in the axial direction, thereby being fixed concentrically with the rotating wheel over the entire circumference. An encoder in which S poles and N poles are alternately arranged in the circumferential direction on the other side surface in the axial direction, and a non-magnetic material covering at least the other side surface in the axial direction of the surface of the encoder A rolling bearing unit with an encoder for an automobile, comprising a cover layer. An outer ring having an inner ring raceway on the outer peripheral surface and not rotating while being supported by a suspension device in use, an outer ring having an outer ring raceway on the inner peripheral face and rotating together with the wheel in use, the outer ring raceway and the inner ring raceway And a plurality of rolling elements provided between the outer ring and an outer peripheral surface of the outer ring, and an S pole and an N pole are alternately arranged over the circumference in the circumferential direction. A rolling bearing unit with an encoder for an automobile, comprising: an arranged encoder; and a cover layer made of a nonmagnetic material that covers at least the outer peripheral surface of the surface of the encoder.

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