JPH0894658A - Rolling bearing unit with rotational-speed detection device - Google Patents

Abstract

PURPOSE: To obtain a rolling bearing unit which prevents a foreign body from creeping into a space used to incorporate a turning body and a sensor and which can be made small and lightweight. CONSTITUTION: A sensor 31 is carried and held at the inside of a cover 27 which has been fitted and fixed to an outer-ring corresponding member 1. A seal ring 37 is arranged on the inside-diameter side of an inside-diameter-side cylinder part 30 constituting the cover 27. The sensor 31 and the seal ring 37 are superposed in the radial direction, the size in the radial direction of a hub 4 is made small, and a rolling bearing unit is made small and lightweight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION A rolling bearing unit with a rotation speed detecting device according to the present invention rotatably supports a wheel of an automobile with respect to a suspension device and detects the rotation speed of the wheel to detect an antilock brake system ( It is used to control ABS) or traction control system (TCS).

[0002]

2. Description of the Related Art The wheels of a motor vehicle must be rotatably supported on a suspension system. Further, in order to control the antilock brake system (ABS) or the traction control system (TCS), it is necessary to detect the rotation speed of the wheels. Various rolling bearing units with a rotation speed detecting device for this purpose have been conventionally proposed. 7 to 8 show the structure among the conventionally known structures,
3 shows the structure described in US Pat. No. 4,988,220.

The member 1 corresponding to the outer ring is supported and fixed to the suspension device by a mounting portion 2 formed on the outer peripheral surface thereof. Therefore, the member 1 corresponding to the outer ring does not rotate during use. An inner ring equivalent member 3 is provided inside the outer ring equivalent member 1 concentrically with the outer ring equivalent member 1 so that the inner ring equivalent member 3 rotates during use. The member 3 corresponding to the inner ring includes a hub 4 and an inner ring 5. Of these, a spline groove 6 is formed on the inner peripheral surface of the hub 4, and a mounting flange 7 is formed on the outer peripheral surface of the outer end (the end that is the outer side in the width direction when assembled to a vehicle; the left end in FIG. 7). are doing. At the time of assembling to a vehicle, a drive shaft which is rotationally driven through a constant velocity joint is inserted into the spline groove 6 and a wheel is fixed to the mounting flange 7.

Double row outer ring raceways 8 and 8 are provided on the inner peripheral surface of the outer ring equivalent member 1, and inner ring raceways 9 and 9 are provided on the intermediate outer peripheral surface of the hub 4 and the outer peripheral surface of the inner ring 5. Is forming. And, these outer ring raceways 8 and 8 and inner ring raceways 9,
Rolling elements 10 and 10 are provided between the inner ring member 9 and the inner ring member 9 so that the inner ring member 3 can freely rotate inside the outer ring member 1. Although balls are used as the rolling elements 10 and 10 in the illustrated example, tapered rollers may be used as the rolling elements in the case of a hub unit for a vehicle that is heavy in weight.

Further, a metal annular holder 11 is fitted into the opening of the inner end of the member 1 corresponding to the outer ring (the end which is the center side in the width direction when assembled to a vehicle, the right end in FIG. 7). It is fixed. A sensor 14 including a permanent magnet 12 and a coil 13 is supported and fixed on the outer peripheral surface of the holder 11. On the other hand, a tone wheel 15 made of a magnetic material is fixed to the outer peripheral surface of the inner end portion of the hub 4, and the outer peripheral surface of the tone wheel 15 and the inner peripheral surface of the sensor 14 are opposed to each other. Gear-shaped irregularities are formed on the outer peripheral surface of the tone wheel 15. Therefore, the voltage induced in the coil 13 changes sinusoidally with the rotation of the member 3 corresponding to the inner ring. Since the frequency at which the voltage changes in this manner is proportional to the rotation speed of the member 3 corresponding to the inner ring, if this voltage is input to the controller of the ABS or TCS as the output signal of the sensor 14, these ABS and TCS can be properly adjusted. You can control.

Further, the base end of a rubber seal ring 16 is locked to the inner peripheral edge of the inner end of the holder 11, and the tip edge of the seal ring 16 is slidably contacted with the outer peripheral surface of the tone wheel 15. There is. On the other hand, the base end portion of another seal ring 17 is fitted and fixed to the inner peripheral surface of the outer end portion of the outer ring equivalent member 1, and the tip edge of this seal ring 17 is slid on the outer peripheral surface of the intermediate portion of the inner ring equivalent member 3. I am in contact. By the pair of inner and outer seal rings 16 and 17, the rolling elements 10 and 10 are formed.
Also, foreign matter such as rainwater and dust is prevented from entering the space 18 in which the tone wheel 15 is installed.

[0007]

However, the conventional rolling bearing unit with the rotational speed detecting device, which is constructed and operates as described above, has the following problems. That is, in the conventional structure shown in FIGS. 7 to 8, the seal ring 16 that closes the inner end opening of the space 18 between the inner peripheral surface of the outer ring equivalent member 1 and the outer peripheral surface of the inner ring equivalent member 3 is located inside the sensor 14. It is provided so as to project to the end side.

For this reason, the dimension of the rolling bearing unit with the rotational speed detecting device in the axial direction (left and right direction in FIG. 7) is increased by the provision of the seal ring 16. And
As the size increases, it becomes necessary to increase the axial size of the hub 4 and the tone wheel 15 that form the member 3 corresponding to the inner ring, resulting in an increase in the size and weight of the rolling bearing unit with a rotation speed detecting device. , Not preferable.
The rolling bearing unit with a rotation speed detecting device of the present invention is intended to solve such a problem.

[0009]

A rolling bearing unit with a rotation speed detecting device according to the present invention has a member equivalent to an outer ring that does not rotate during use and a member corresponding to the outer ring, like the above-described conventional rolling bearing unit with a rotation speed detecting device. An inner ring equivalent member which is provided concentrically with the member and rotates together with the wheel during use, an outer ring raceway formed on the inner peripheral surface of the outer ring equivalent member, and an inner ring raceway formed on the outer peripheral surface of the inner ring equivalent member, A plurality of rolling elements provided between the outer ring raceway and the inner ring raceway,
A tone wheel supported by the member corresponding to the inner ring and rotating together with the member corresponding to the inner ring, a cover supported by an inner end opening of the member corresponding to the outer ring, and a sensor supported by the cover and facing the tone wheel. , And a seal ring provided between the cover and the member corresponding to the inner ring.

Particularly, in the rolling bearing unit with the rotational speed detecting device of the present invention, the cover is an outer diameter side cylindrical portion fitted and fixed to the inner end portion of the outer ring equivalent member, and the outer diameter side cylindrical portion. A circular ring part bent from the inner end of the part to the inner diameter side,
The inner ring side cylindrical portion is bent outward from the inner peripheral edge of the circular ring portion. The sensor is held in a portion between the outer diameter side cylindrical portion and the inner diameter side cylindrical portion, and the seal ring is provided on the inner diameter side of the inner diameter side cylindrical portion.

[0011]

The action of the rolling bearing unit with a rotation speed detecting device of the present invention constructed as described above for rotatably mounting the wheel to the suspension device and the action of detecting the rotation speed of the wheel have been described above. This is similar to the conventional rotation speed detection device.

Particularly, in the case of the rolling bearing unit with the rotational speed detecting device of the present invention, the sensor and the seal ring are arranged in a state of being overlapped with each other in the diametrical direction, so that the seal ring is axially arranged from the inner end surface of the cover. It does not stick out.
Therefore, the size of the rolling bearing unit with the rotation speed detecting device in the axial direction can be reduced, and the size and weight of the unit can be reduced.

[0013]

1 and 2 show an embodiment of the present invention. The outer ring equivalent member 1 that does not rotate during use has double rows of outer ring raceways 8 on the inner peripheral surface. The member 1 corresponding to the outer ring can be supported by the suspension device by a mounting portion 2 formed on the outer peripheral surface thereof. An inner ring-corresponding member 3 is arranged inside the outer ring-corresponding member 1. The member 3 corresponding to the inner ring is composed of a hub 4 and an inner ring 5, and rotates during use. On the outer peripheral surface of the intermediate portion of the hub 4, of these double-row outer ring raceways 8, 8
The inner ring raceway 9 that faces the outer ring raceway 8 on the outer side (the side that is the outer side in the width direction when assembled to the vehicle; the left side in FIG. 1) is also inside the inner ring 5 (widthwise direction when assembled to the vehicle. Outer ring raceway 8 on the inner side, which is the right side of Fig. 1)
The inner ring raceways 9 facing each other are respectively formed. or,
A spline groove 6 is formed on the inner peripheral surface of the hub 4.

A plurality of rolling elements 10, 10 held by cages 23, 23 are provided between the outer ring raceways 8, 8 and the inner ring raceways 9, 9 respectively, and the outer ring equivalent member 1 is provided. An inner ring equivalent member 3 is rotatably supported on the inner diameter side of the. A seal ring 17 is mounted between the outer peripheral surface of the hub 4 near the outer end (the left end in FIG. 1) and the inner peripheral surface of the outer ring equivalent member 1 near the outer end. The outer end opening of the space 18 where the rolling elements 10 and 10 are installed is closed. Further, a mounting flange 7 for fixing the wheel is provided at a portion of the outer end portion of the hub 4 projecting from the outer end opening of the outer ring equivalent member 1.

The inner end of the hub 4 (right end in FIG. 1)
The inner ring 5 is fixed to the hub 4 by screwing and tightening the nut 20 onto the male screw portion 19 formed on the outer ring 19 while the inner ring 5 is externally fitted. The outer peripheral surface of the nut 20 is a cylindrical surface to prevent interference with a tone wheel 21 described later. Accordingly, the nut 20 is provided with a plurality of locking holes 22, 22 for locking the tightening tool in the axial direction (see FIG. 1).
~ 2 left and right).

On the other hand, a tone wheel 21 is provided at the inner end of the inner race 5 at a portion deviated from the inner raceway 9. The tone wheel 21 has a crank-shaped cross section and is formed into a cylindrical shape by pressing a magnetic metal plate. The tone wheel 21 has a large-diameter portion 24 for external fitting and fixing to the inner end portion of the inner ring 5, and a step portion 25 bent from the inner end edge of the large-diameter portion 24 toward the inner diameter side.
And a small diameter portion 26 continuous from the inner peripheral edge of the step portion 25 toward the inside. Then, a large number of notches 33, 33 are formed in the small diameter portion 26 at equal intervals in the circumferential direction, and the small diameter portion 26 is formed in a comb tooth shape. In such a tone wheel 21, the large-diameter portion 24 is externally fitted to the inner end portion of the inner ring 5, and the step portion 25 is abutted against the outer peripheral edge of the inner end portion of the inner ring 5. Fixed to.

A cover 27 is externally fitted and fixed to the inner end opening of the outer ring equivalent member 1. This cover 27
Is formed by drawing a metal plate such as a stainless steel plate into an annular shape with an L-shaped cross section. The cover 27 includes an outer diameter side cylindrical portion 28 and the outer diameter side cylindrical portion 2
The circular ring portion 29 is bent from the inner end portion of 8 to the inner diameter side, and the inner diameter side cylindrical portion 30 is bent from the inner peripheral edge of the circular ring portion 29 to the outer side. Then, the outer diameter side cylindrical portion 28 is externally fitted to the inner end portion of the outer ring equivalent member 1 so as to be fixed to the inner end opening of the outer ring equivalent member 1.

A sensor 31 is supported and fixed inside the cover 27 fixed to the member 1 corresponding to the outer ring in this manner. In the case of the illustrated embodiment, in order to increase the output change of the sensor 31 due to the rotation of the wheel, the sensor 31
Is formed in an annular shape, and the inner peripheral surface of the sensor 31 and the outer peripheral surface of the small diameter portion 26 of the tone wheel 21 are opposed to each other over the entire circumference with a minute gap. For this purpose, the pole piece 32 constituting the sensor 31 is formed in an annular shape as a whole with a substantially J-shaped cross section. This pole piece 32 has a large number of notches 3 in the circumferential direction.
4, 34 are notches 33 formed in the small diameter portion 26,
It is formed at the same pitch as 33. The cutouts 34, 34 are formed so as to face the outer peripheral surface of the small-diameter portion 26. The annular permanent magnet 35 is magnetized in the diametrical direction, its inner peripheral surface faces the outer peripheral surface of the small diameter portion 26, and its outer peripheral surface abuts or approaches the inner peripheral surface of the pole piece 32. I am letting you. Further, the coil 36, which is also formed in an annular shape, is held by the pole piece 32.

Such a sensor 31 is embedded in a synthetic resin 45 formed in an annular shape, and is covered with the cover 27.
Being held inside. The code 41 shown in FIGS.
Is for sending the detection signal of the sensor 31 to the controller of ABS or TCS. The cord 41 communicating with the coil 36 is taken out of the cover 27 through a through hole 42 formed in the circular ring portion 29 of the cover 27. A concave groove 43 is formed at a position surrounding the base end portion of the cord 41 on the inner side surface (the right side surface in FIGS. 1 and 2) of the synthetic resin 45. An O-ring 44 having a thickness dimension in the free groove larger than the depth dimension of the groove 43 is formed in the groove 43.
I am wearing. With the synthetic resin 45 pushed into the cover 27, the O-ring 44 makes elastic contact with the outer side surface (the left side surface in FIGS. 1 and 2) of the circular ring portion 29. As a result, it is possible to prevent rainwater and the like from entering the cover 27 from the takeout portion of the cord 41. It is also possible to adopt a structure in which the coil 36 and the cord are connected by fixing a connector on the outer surface of the cover 27 and inserting a plug provided at the end of the cord into this connector. Also in this case,
Seal the connector installation area with an O-ring.

However, the feature of the present invention resides in that the rolling bearing unit with the rotational speed detecting device can be made smaller and lighter by devising the mounting position of the seal ring 37 described below. Therefore, the structure of the sensor 31 is not particularly limited. Not only the so-called passive type rotation speed detecting device that changes the voltage induced in the coil 36 according to the density change of the magnetic flux passing through the pole piece 32 as shown in the drawing, but also a so-called active type rotation speed detecting device is used. It can also be used. When an active type rotation speed detecting device is used, a permanent magnet whose magnetic poles alternate in the circumferential direction are used as a tone wheel, and a magnetic detecting element such as a Hall IC is incorporated in the sensor.

In particular, in the case of the rolling bearing unit with the rotational speed detecting device of the present invention, the seal ring 37 is mounted inside the cylindrical portion 30 on the inner diameter side of the cover 27. The seal ring 37 is made of a cored bar 38 having a substantially L-shaped cross section and an annular shape as a whole, and an elastic material such as rubber or elastomer, and is attached to the inner peripheral edge of the cored bar 38 over the entire circumference thereof. And a seal lip 39 that has been formed. Such a seal ring 37 is fixed to the cover 27 by fitting the core metal 38 into the inner diameter side cylindrical portion 30. On the other hand, a small diameter portion 40 is formed at a portion of the inner end portion of the nut 20 facing the inner diameter side cylindrical portion 30 to prevent interference between the nut 20 and the cover 27 and the seal ring 37. The tip edge of the seal lip 39 is brought into sliding contact with the base end portion (the left end portion in FIGS. 1 and 2) of the small diameter portion 40. As a result, the inner end opening of the space 18 is closed by the seal ring 37.

The rolling bearing unit with a rotation speed detecting device of the present invention configured as described above supports the wheel rotatably with respect to the suspension device, and the action of detecting the rotation speed of the wheel is as follows. This is similar to the above-described conventional rolling bearing unit with a rotation speed detecting device.

In particular, in the case of the rolling bearing unit with the rotation speed detecting device of the present invention, the sensor 31 for detecting the rotation speed is used.
And a seal ring 37 for closing the inner end opening of the space 18.
And are arranged in a state of overlapping in the diametrical direction (vertical direction in FIGS. 1 and 2), the seal ring 37 covers
Does not project in the axial direction (rightward in FIGS. 1 and 2) from the inner end surface (rightward in FIGS. 1-2). Therefore, the size of the rolling bearing unit with a rotation speed detecting device in the axial direction (the left-right direction in FIG. 1) can be reduced, and the unit can be made smaller and lighter.

Next, FIG. 3 shows a second embodiment of the present invention. In the case of the present embodiment, the large diameter portion 46 is formed at the outer end portion (the left end portion in FIG. 3) of the outer diameter side cylindrical portion 28 forming the cover 27, and the large diameter portion 46 and the outer diameter side cylindrical portion are formed. The main body 28 is continuous with the step 47. In order to mount the cover 27 on the outer ring equivalent member 1, the large diameter portion 46 is fitted onto the inner end portion of the outer ring equivalent member 1 and the step portion 47 is formed on the inner peripheral edge of the outer peripheral member 1. Strike. With this structure, the press-fitting amount of the cover 27 can be regulated, and the cover 2
By press-fitting 7 too much, the sensor 31 held by the cover 27 will not be damaged.

Further, in the case of the present embodiment, the axial length of the nut 20a is shortened so that the small diameter portion 4 as in the above-mentioned first embodiment.
0 is omitted. An inner seal ring 48 is externally fitted and fixed to a portion of the inner end portion of the hub 4 protruding from the nut 20a. A tip end of a seal lip 39 that constitutes the seal ring 37 is in sliding contact with a core metal 49 that constitutes the inner seal ring 48. The tip edge of the seal lip 50 forming the inner seal ring 48 is in sliding contact with the core metal 38 forming the seal ring 37. By double sealing in this way, the sealing property of the inner end opening of the space 18 is improved.

The cored bar 38 for forming the seal ring 37 does not necessarily have to be formed separately from the cover 27 as shown in FIGS. For example, as in the third embodiment shown in FIG. 4, the distal end portion of the inner diameter side cylindrical portion 30 of the cover 27 is bent at a right angle to the inner diameter side (upper side in FIG. 4) to form an annular extension 51.
The seal ring 37 can also be configured by using the extension portion 51 as a core metal. Other configurations and operations are similar to those of the above-described first embodiment, and therefore, the same reference numerals are given to the same portions and duplicate description will be omitted.

Next, FIG. 5 shows a fourth embodiment of the present invention. In the case of this embodiment, a step portion 52 is formed on the outer peripheral surface of the outer end portion of the member 1 corresponding to the outer ring, and the end edge of the outer diameter side cylindrical portion 28 forming the cover 27 is abutted against the step portion 52. The amount of press-fitting of the cover 27 into the outer ring equivalent member 1 is restricted. Further, the nut 20b is made rotatable by engaging a tool with a gear-shaped unevenness formed on the outer peripheral edge.

The tone wheel 2 used in this embodiment is also used.
1a also serves as a rotation washer for the nut 20b. For this reason, a locking projection 53 protruding toward the inner diameter side is formed on a part of the inner peripheral surface of the tone wheel 21a, and a locking recess 54 is formed on a part of the outer peripheral surface of the hub 4.
When assembling the rolling bearing unit, these locking projections 53
And the locking recess 54 are engaged with each other to prevent the tone wheel 21a from rotating with respect to the hub 4. Then, after tightening the nut 20b, the tongue piece 55 provided on a part of the tone wheel 21a is bent toward the inner diameter side (lower side in FIG. 5) to form the tongue piece 55 and the concave portion on the outer peripheral surface of the nut 20b. Engage. As a result, the nut 20
b does not rotate with respect to the hub 4, and the nut 20b is prevented from loosening.

Further, in the case of the present embodiment, a receiving plate 56 having an L-shaped cross section and an annular shape as a whole is externally fitted and fixed to a portion projecting from the nut 20b at an inner end portion of the hub 4. .
The tip edge of the seal lip 39 attached to the extension portion 51 of the cover 27 is slidably contacted with the receiving plate 56. Further, in the tone wheel 21a, a large number of through holes 60 are formed at regular intervals in the circumferential direction instead of the notches. Other configurations and operations are similar to those of the above-described first embodiment, and therefore, equivalent parts will be denoted by the same reference numerals and redundant description will be omitted.

Next, FIG. 6 shows a fifth embodiment of the present invention. In the case of the present embodiment, the seal ring 57 is externally fitted and fixed to the portion of the inner end portion of the hub 4 protruding from the nut 20a. The seal ring 57 includes a cored bar 58 having an L-shaped cross section and an annular shape as a whole, and a seal lip 59 having a base end portion attached to the cored bar 58. The hub 4
The core metal 58 of these is externally fitted and fixed to the inner end portion of the. The tip edge of the seal lip 59 is connected to the inner peripheral surface of the inner diameter side cylindrical portion 30 forming the cover 27 and the extension portion 5.
It is in sliding contact with the inner surface of 1. Other configurations and operations are similar to those of the above-described first embodiment, and therefore, equivalent parts will be denoted by the same reference numerals and redundant description will be omitted.

[0031]

Since the rolling bearing unit with a rotation speed detecting device of the present invention is constructed and operates as described above, it is possible to reliably prevent foreign matter from entering the inside and to improve reliability and durability. At the same time, the size and weight can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is an enlarged view of the right part of FIG.

FIG. 3 is a view similar to FIG. 2, showing a second embodiment of the present invention.

FIG. 4 is a partial sectional view of an inner peripheral portion of a cover and a seal ring, showing the third embodiment.

FIG. 5 is a sectional view showing the fourth embodiment and corresponding to the upper part of FIG. 2;

FIG. 6 is a view similar to FIG. 2 showing the fifth embodiment.

FIG. 7 is a sectional view showing an example of a conventional structure.

8 is a cutaway perspective view of a portion A of FIG.

[Explanation of symbols]

 1 Outer Ring Equivalent Member 2 Mounting Part 3 Inner Ring Equivalent Member 4 Hub 5 Inner Ring 6 Spline Groove 7 Mounting Flange 8 Outer Ring Raceway 9 Inner Ring Raceway 10 Rolling Element 11 Holder 12 Permanent Magnet 13 Coil 14 Sensor 15 Tone Wheel 16, 17 Seal Ring 18 Space 19 Male screw portion 20, 20a, 20b Nut 21, 21a Tone wheel 22 Locking hole 23 Retainer 24 Large diameter portion 25 Step portion 26 Small diameter portion 27 Cover 28 Outer diameter side cylindrical portion 29 Circle ring portion 30 Inner diameter side cylindrical portion 31 Sensor 32 Pole piece 33, 34 Notch 35 Permanent magnet 36 Coil 37 Seal ring 38 Core bar 39 Seal lip 40 Small diameter part 41 Code 42 Through hole 43 Groove 44 O ring 45 Synthetic resin 46 Large diameter part 47 Step part 48 Inner seal ring 49 Core metal 50 Seal lip 51 Extension part 5 Stepped portion 53 locking projection 54 engaging the recess 55 tongue 56 receiving plate 57 sealing ring 58 metal core 59 the sealing lip 60 hole

Claims (1)

[Claims] 1. An outer ring equivalent member that does not rotate during use, an inner ring equivalent member that is provided concentrically with the outer ring equivalent member and rotates with the wheel during use, and an outer ring raceway formed on the inner peripheral surface of the outer ring equivalent member. An inner ring raceway formed on the outer peripheral surface of the inner ring equivalent member, a plurality of rolling elements provided between the outer ring raceway and the inner ring raceway, and supported by the inner ring equivalent member to rotate together with the inner ring equivalent member. A tone wheel, a cover supported by the inner end opening of the member corresponding to the outer ring, a sensor supported by the cover and facing the tone wheel, and provided between the cover and the member corresponding to the inner ring. In a rolling bearing unit with a rotation speed detection device including a seal ring, the cover includes an outer diameter side cylindrical portion fitted and fixed to an inner end portion of the outer ring equivalent member, and an inner diameter side cylindrical portion of the outer diameter side cylindrical portion. A circular ring portion bent from the end portion to the inner diameter side and an inner diameter side cylindrical portion bent from the inner peripheral edge of the circular ring portion to the outer side are provided, and the sensor is provided between the outer diameter side cylindrical portion and the inner diameter side cylindrical portion. A rolling bearing unit with a rotational speed detecting device, wherein the rolling bearing unit is held by a portion and the seal ring is provided on the inner diameter side of the inner diameter side cylindrical portion.