JP3725133B2 - Wheel speed detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention includes a pulsar ring provided on a rotating member that rotates together with a wheel, and a wheel speed sensor having a detection portion facing the pulsar ring at a tip portion. The present invention relates to a wheel speed detection device that is inserted into an insertion hole provided in the support member and attached to the support member.
[0002]
[Prior art]
Conventionally, such a wheel speed detection device is already known from, for example, Patent Document 1 and the like.
[0003]
[Patent Document 1]
Utility Model Registration No. 2572198 Publication [0004]
[Problems to be solved by the invention]
By the way, in order to prevent water and dust from entering from the outside between the detecting portion provided at the tip of the wheel speed sensor and the pulsar ring, the wheel speed sensor is inserted into the insertion hole of the support member. In some cases, it may be necessary to seal the insertion portion. In such a case, it is considered that a seal member such as an O-ring is simply interposed between the wheel speed sensor and the support member. This increases the number of parts.
[0005]
On the other hand, if the wheel speed sensor is tilted in the insertion hole, the air gap between the tip of the wheel speed sensor and the pulsar ring may vary, leading to a decrease in detection accuracy. I want to prevent the sensor from tilting as much as possible.
[0006]
The present invention has been made in view of such circumstances, achieves a seal between the wheel speed sensor and the support member while avoiding an increase in the number of parts, and prevents the wheel speed sensor from being inclined in the insertion hole. It is an object of the present invention to provide a wheel speed detection device that can be obtained.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises a pulsar ring provided on a rotating member that rotates together with a wheel, and a wheel speed sensor having a detection portion facing the pulsar ring at the tip, In a wheel speed detection device in which a housing made of resin is inserted into an insertion hole provided in a support member on the vehicle body side and attached to the support member, the insertion hole includes a first insertion hole near the axle and the first composed of a second insertion hole which is spaced from the axle has an insertion hole and the same axis, the housing is inserted loosely into the second insertion hole, it is inserted into the first insertion hole of the housing At least one rib arranged on a plane inclined with respect to the axis of the insertion hole is elastically in contact with the inner surface of the first insertion hole all around the outer periphery of the distal end. hand To be set to the first feature.
[0008]
In addition, the present invention is characterized in that, in the first aspect of the present invention, the pulsar ring is arranged in parallel to the axis of the insertion hole.
[0009]
According to such a configuration, when the housing of the wheel speed sensor is inserted into the insertion hole by light press-fitting or the like, the rib on the outer periphery of the housing elastically contacts the entire inner surface of the first insertion hole. This eliminates the need for a seal member, avoids an increase in the number of parts, achieves a seal between the wheel speed sensor and the support member, and prevents the wheel speed sensor from tilting in the insertion hole to ensure an air gap. Moreover, since at least one of the ribs is disposed on a plane inclined with respect to the axis of the insertion hole, it is possible to reduce a load when lightly press-fitting the housing of the wheel speed sensor into the insertion hole. .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.
[0011]
1 to 3 show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view in the vicinity of a wheel, FIG. 2 is an enlarged view of a main part of FIG. 1, and FIG. 3 is a side view of a wheel speed sensor. .
[0012]
First, in FIG. 1, a wheel W is a drive wheel to which, for example, a drum brake B is mounted. A plurality of, for example, four bolts 3. Installed by.
[0013]
The brake drum 2 is integrally provided with a cylindrical hub 5, and an axle 8 connected to the drive shaft 6 via a universal joint 7 is splined to the hub 5. The back plate 9 of the drum brake B is attached to a bearing housing 10 as a support member suspended from a vehicle body (not shown).
[0014]
The bearing housing 10 is provided with a support hole 11 that coaxially surrounds the axle 8, a step portion 8 a provided on the inner end side of the axle 8 facing the hub 5 side, and an inner end of the hub 5. Between the outer periphery of the axle 8 and the inner periphery of the support hole 11, a first angular bearing 12 on the axially outer side and a second angular bearing 13 on the axially inner side are interposed in parallel. Is done. The outer rings 12 a and 13 a of the first and second angular bearings 12 and 13 are in contact with each other and are fitted into the bearing housing 10, and the outer end of the support hole 11 has the first angular bearing 12. A retaining ring 14 for abutting the outer ring 12a is fitted.
[0015]
The axle 8 has a screw shaft portion 8b protruding from the hub 5 coaxially at the outer end, and a washer 16 is interposed between the presser ring 15 contacting the tapered portion 5a provided at the outer end portion of the hub 5. By screwing the tightened nut 17 into the screw shaft portion 8b and tightening, the inner rings 12b and 13b of the first and second angular bearings 12 and 13 which are in contact with each other are connected to the step portion 8a and the hub 5 of the axle 8. The inner rings 12b and 13b rotate together with the axle 8 or the wheels W.
[0016]
A first dust seal 18 is fitted to the outer end portion of the outer ring 12 a in the first angular bearing 12, and the first dust seal 18 elastically slides on the outer periphery of the outer end portion of the inner ring 12 b in the first angular bearing 12. . Also the inner end portion outer periphery of the hub 5 in outward from the retaining ring 1 4, the cover ring 19 to form a slight annular gap between the outer ring 12a inner surface of the first angular bearing 12 is fixed by press fitting or the like The
[0017]
Referring also to FIG. 2, a second dust seal 20 is fitted to the inner end portion of the outer ring 13 a in the second angular bearing 13, and a receiving member 21 as a rotating member for slidingly contacting the second dust seal 20. Is fixed to the outer periphery of the inner end of the inner ring 13b of the second angular bearing 13 by press fitting or the like. This receiving member 21 has a ring plate portion 21 a along a plane orthogonal to the axis of the axle 8 and is formed in a substantially L-shaped cross section. Together with the inner ring 13 b of the second angular bearing 13, that is, the wheel W. A pulsar ring 22 is provided on the ring plate portion 21 a of the rotating receiving member 21.
[0018]
The pulsar ring 22 is made of a magnetic metal powder that is magnetized on the surface opposite to the slidable contact surface of the second dust seal 20 in the ring plate portion 21a so that a plurality of portions spaced at equal intervals in the circumferential direction are magnetized. The blended rubber is baked, and the wheel speed sensor 23 is attached to the bearing housing 10 so that the detection portion 23a at the tip is opposed to the pulsar ring 22.
[0019]
The bearing housing 10 is provided with a first insertion hole 24 close to the axle 8 and a second insertion hole 25 arranged away from the axle 8 with the same axis line along the radial direction of the axle 8. The Accordingly, the axes of the first and second insertion holes 24 and 25 are parallel to the pulsar ring 22. Between the first and second insertion holes 24 and 25, the bearing housing 10 is formed with a lightening recess 26 for weight reduction, and the outer end of the second insertion hole 25 is formed in the bearing housing 10. An opening is made in the flat mounting surface 27.
[0020]
In FIG. 3, the wheel speed sensor 23 includes a synthetic resin housing 28 inserted into the first and second insertion holes 24, 25, and the front end of the housing 28 is detected in the detection portion 23a. As described above, the IC module 29 and the like are incorporated.
[0021]
Moreover the rear portion of the housing 28, a flange portion 28a which is brought into contact with the mounting surface 27 of the bearing housing 10 is inserted into the collar 3 1 made is provided integrally, it is embedded in the flange portion 28a metal The bolt 32 is screwed into the bearing housing 10.
[0022]
By the way, the housing 28 is loosely inserted into the second insertion hole 25, but is lightly press-fitted into the first insertion hole 24, and the tip is inserted into the first insertion hole 24. On the entire outer periphery of the housing 28, at least one rib 30 arranged in a plane inclined with respect to the axis of the first insertion hole 24, in this embodiment, one rib 30, is triangular in a natural state where no external force acts. And projecting integrally so as to have a cross-sectional shape. Thus, when the housing 28 is inserted into the first insertion hole 24, it is required to lightly press the rib 30 so that the rib 30 is crushed. The rib 30 is inserted into the inner surface of the first insertion hole 24 by light press-fitting. Closely elastically over the lap.
[0023]
In addition, a cover ring 33 that covers from the universal joint 7 side a portion where the detection portion 23a of the wheel speed sensor 23 faces the pulsar ring 22 is provided on the outer periphery of the axle 8 with a slight annular gap between the bearing housing 10 and the bearing ring 10. It is fixed by press fitting or the like so as to form.
[0024]
Next, the operation of this embodiment will be described. One rib 30 is projected from the entire outer periphery of the tip portion inserted into the first insertion hole 24 of the synthetic resin housing 28 provided in the wheel speed sensor 23. When the housing 28 of the wheel speed sensor 23 is lightly press-fitted into the first insertion hole 24, the rib 30 elastically contacts the entire inner surface of the first insertion hole 24, so that a dedicated seal member is not necessary. While avoiding an increase in the number of points, a seal between the wheel speed sensor 23 and the bearing housing 10 is achieved, and the wheel speed sensor 23 is prevented from being tilted in the first insertion hole 24, so And an air gap between the pulsar rings 22 can be guaranteed.
[0025]
In addition, since the rib 30 is disposed on the housing 28 so as to be disposed on a plane inclined with respect to the axis of the first insertion hole 24, the housing 28 of the wheel speed sensor 23 is lightly press-fitted into the first insertion hole 24. The load at the time can be reduced.
[0026]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.
[0027]
For example, although the wheel speed detection device for detecting the wheel speed of the driving wheel has been described in the above embodiment, the present invention can be applied to the wheel speed detection device for the driven wheel.
[0028]
【The invention's effect】
As described above, according to the present invention, a dedicated seal member is not required and an increase in the number of parts is avoided, and a seal between the wheel speed sensor and the support member is achieved and the wheel speed sensor is inclined in the insertion hole. Thus, the air gap can be ensured, and the load when the wheel speed sensor housing is lightly press-fitted into the insertion hole can be reduced.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view in the vicinity of a wheel.
FIG. 2 is an enlarged view of a main part of FIG.
FIG. 3 is a side view of a wheel speed sensor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Bearing housing 21 as a supporting member ... Receiving member 22 as a rotating member ... Pulsar ring 23 ... Wheel speed sensor 23a ... Detection part 24 ... 1st insertion hole
25 ... 2nd insertion hole 28 ... Housing 30 ... Rib W ... Wheel

Claims (2)

A pulsar ring (22) provided on a rotating member (21) rotating together with the wheel (W), and a wheel speed sensor (23) having a detection portion (23a) opposed to the pulsar ring (22) at a tip portion. The housing (28) made of synthetic resin for the wheel speed sensor (23) is inserted into the insertion holes (24 , 25 ) provided in the support member (10) on the vehicle body side and attached to the support member (10). In the wheel speed detecting device, the insertion holes (24, 25) have a first insertion hole (24) near the axle (8) and the same axis as the first insertion hole (24), from the axle (8). The housing (28) is loosely inserted into the second insertion hole (25), and the first insertion hole (24) of the housing (28) is formed . ) to the outer periphery of the inserted distal portion all , Said insertion hole (24, 25) at least one strip of ribs are arranged in inclined planes with respect to the axis (30) is resiliently entire periphery to the inner surface of the first insertion hole (24) A wheel speed detecting device, which protrudes so as to be in close contact with the wheel. 2. A wheel speed detecting device according to claim 1, wherein the pulsar ring (22) is arranged parallel to the axis of the insertion hole (24, 25).

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