JP2001336525A - Wheel support structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem with a conventional wheel support structure that in an arrangement wherein a rotation sensor is positioned near roller bearings heated by application of load derived from the weight of a vehicle during travel of the vehicle, the sensor is readily affected by heat and decreases its functions, making it difficult to detect the correct rotating speed. SOLUTION: A speed detection apparatus 30 for detecting the rotating speed of a driveshaft 2 is disposed in a position near the end 27 of a seal boot 25 adapted for preventing foreign matter from entering a constant velocity joint 4. Thus, because the speed detection apparatus 30 is disposed away from double row roller bearings 17 being heated, the speed detection apparatus 30 is unaffected by the heat of the double row roller bearings 17 and can therefore detect the rotating speed of a wheel with accuracy over a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel support structure, and more particularly to an anti-lock brake system (hereinafter referred to as "AB").
S ”) in a vehicle provided with the same.

[0002]

2. Description of the Related Art A conventional wheel supporting structure is disclosed in
There is a technique described in Japanese Patent No. 43411. 6 and 7
As shown in FIG.
A constant velocity joint 82 connected to an end of a drive shaft 81 and an outer cylindrical body 83 of the constant velocity joint 82. Are inserted and a wheel (not shown) is fixed via a bolt 85 to a flange 84 formed on the outer peripheral surface. A ball 87 is formed by using the outer peripheral surfaces of the hub wheel 86 and the outer cylindrical body 83 as inner rings. A rolling bearing (for example, a double-row rolling bearing is used) 89 for rolling. A knuckle N is fixed to a flange 91 formed on the outer peripheral surface of the outer ring 90 of the rolling bearing 89 by a bolt 92.

[0003] At the end of the outer race 90, an extension 93 is formed extending toward the inner end in the axial direction.
A seal member 94 for sealing a gap between the outer race 90 and the outer cylinder 83 of the constant velocity joint 82 is provided.
A rotation sensor 95 for detecting the rotation speed of the wheel is arranged in a space between the outer cylinder 3 and the outer cylindrical body 83 of the constant velocity joint 82.

In the wheel support structure 80, when the drive shaft 81 rotates, the wheels rotate through the constant velocity joint 82 and the hub wheel 86, and the rotational speed of the wheels is controlled by the rotation of the outer cylinder 83 of the constant velocity joint 82. The speed is detected by the rotation sensor 95, and according to the rotation speed, the wheel is controlled so as not to lock during braking. In addition, a gap between the outer ring 90 and the outer cylinder 83 of the constant velocity joint 82 is sealed by the seal member 94, thereby preventing muddy water, sand, and the like from entering the gap.

[0005]

In the above-mentioned conventional wheel supporting structure 80, a load based on the weight of the vehicle acts on the rolling bearing 89, and therefore, especially when the vehicle is running, the rolling bearing 89 is caused by this load. It will be in a heated state.

The wheel support structure 80 has a configuration in which a rotation sensor 95 is disposed in a space between the extension 93 and the outer cylindrical body 83 of the constant velocity joint 82.
Because it is close to 9, it is easily affected by heat. Then, when affected by heat, the function of the rotation sensor 95 is reduced,
It becomes difficult to detect an accurate rotation speed.

[0007] In view of the above problems, it is an object of the present invention to provide a wheel support structure capable of accurately detecting the rotation speed of a wheel even when the rolling bearing is heated.

[0008]

Means for Solving the Problems In the present invention, a hub wheel for supporting a wheel is attached to an end of a drive shaft via a constant velocity joint, and a rolling bearing is mounted on the hub wheel. The outer race of the rolling bearing and the vehicle body are fixed via a support member, and a seal boot for preventing foreign matter from entering the constant velocity joint is provided. One end of the seal boot is provided. The part is fitted around the cylindrical surface of the constant velocity joint,
And the other end of the seal boot is disposed so as to fit over the peripheral surface of the drive shaft, and a speed detection for detecting the rotational speed of the drive shaft is provided at a position near the other end of the seal boot. Equipment is provided.

Further, the speed detecting device includes a detected member which rotates together with the drive shaft, and a detecting member arranged opposite to the detected member.

[0010] Further, a bearing is provided between the peripheral surface of the drive shaft and the other end of the seal boot.
The detected member of the speed detecting device is mounted, and the detecting member of the speed detecting device is mounted on the outer ring of the bearing so as to face the detected member.

In each of the above constructions, the speed detecting device is provided at a position near the other end of the seal boot, that is, at a position separated from the rolling bearing, so that the speed detecting device is
It is less susceptible to heat from the rolling bearings that heat up during traveling, and therefore prevents the function of the speed detector from lowering and maintains a state in which the rotational speed of the wheel is accurately detected for a long time.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A wheel support structure according to an embodiment of the present invention will be described below with reference to the drawings. First, a first embodiment of the present invention will be described with reference to FIG.

In a wheel support structure 1 according to a first embodiment of the present invention, a hub wheel 3 for supporting wheels (not shown) is provided with a constant velocity joint 4 at one end of a drive shaft 2 (drive shaft). Mounted through. The constant velocity joint 4 is, for example, a Zeppa type (Barfield type) constant velocity joint.
Is an outer cylinder 6 also serving as an outer ring, an inner ring 7, and a plurality of balls 8
And an outer end of the outer cylinder 6 in the axial direction is reduced in diameter, and the reduced diameter portion 10 is spline-fitted into a mounting hole 11 formed in the center of the hub wheel 3. Is inserted through.

The other end of the drive shaft 2 is attached to the other hub wheel (not shown) via the other constant velocity joint 12.

An annular flange 13 is formed at the outer end of the hub wheel 3 in the axial direction, and the wheel is fixed to the flange 13 via a bolt 15.

A double row rolling bearing 17 is mounted on the hub wheel 3.
The double-row rolling bearing 17 has an inner ring member having an inner ring member 18 having a single raceway fitted on an intermediate portion of the outer peripheral surface of the hub wheel 3 and an axially inner end side of the hub wheel 3. It comprises a single outer ring 19 having two rows of raceways, a plurality of balls 20 arranged in two rows, and two crown retainers 21.

Flanges 14 are formed at predetermined intervals on the outer peripheral surface of the outer ring 19 of the double row rolling bearing 17.
Knuckle (an example of a supporting member) 22 fixed by 6
Mounted through.

A bellows-like seal boot 25 (made of, for example, synthetic rubber) for preventing foreign substances such as muddy water and sand from entering the constant velocity joint 4 is provided. Of the outer cylinder 6 of the constant velocity joint 4 is fitted on the inner end side in the axial direction, and the other end 27 of the seal boot 25 is fitted on the peripheral surface of the drive shaft 2 in the middle. Thus, it is arranged so as to pass from the outer cylinder 6 to the drive shaft 2 as a whole. One end 26 of the seal boot 25 is attached to the outer cylinder 6 by a band 28 with an appropriate fastening force, and the other end 27 of the seal boot 25 is
Is attached to the drive shaft 2 by another band 29 with an appropriate fastening force.

At a position near the other end 27 of the seal boot 25, a speed detecting device 30 for detecting the rotational speed of the drive shaft 2 is provided.
Is wound around the drive shaft 2 on the inner end side of the other end 27 of the seal boot 25 in the axial direction, and a large number of N poles and S poles are alternately magnetized on the surface. A rubber sheet serving as a member 32 and a hole serving as a detection member 33 which is disposed to face the rubber sheet and is attached to the vehicle body side and detects a pulse generated from the detected member 32 with the rotation of the drive shaft 2. And an IC.

It is to be noted that this Hall IC is a well-known one, and has a structure in which a main body 34 made of synthetic resin is molded with an IC chip, and the IC chip is embedded so that the lower surface of the main body 34 serves as a sensor surface. A code line 35 for transmitting a signal to a signal processing circuit of an ABS (not shown) is drawn out from the upper surface of the main body 34.

In the above configuration, when the drive shaft 2 rotates, the hub wheel 3 rotates around the axis through the constant velocity joint 4 while being supported by the double-row rolling bearing 17. The wheels rotate and the vehicle travels. At this time, the weight of the vehicle is acting on the double row rolling bearing 17, and the load heats the double row rolling bearing 17 portion.

By the way, as the drive shaft 2 rotates, the detected member 32 attached to the drive shaft 2 rotates,
As a result, a pulse signal is generated. This pulse signal is
A pulse signal sequentially detected by the detection member 33 and detected in a unit time is input to a signal processing circuit of the ABS, where the pulse signal input from the detection member 33 and the diameter of the wheel previously input are output. The rotational speed of the drive shaft 2 is calculated based on information such as dimensions to prevent the wheels from locking during braking.

Then, as described above, the double row rolling bearing 1
Even if the portion 7 is heated by receiving a load due to the weight of the vehicle, the speed detecting device 30 can detect the position from the double row rolling bearing 17 such as a position near the other end 27 of the seal boot 25. Since it is arranged at a separated position, there is no adverse effect due to the heat generated in the double-row rolling bearing 17 portion. Therefore, even if the double-row rolling bearing 17 portion is in a heated state, the speed detecting device is provided. 30 allows the rotation speed of the drive shaft 2 to be detected accurately and for a long time.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the wheel support structure 1 according to the second embodiment of the present invention, the one end 26 of the seal boot 25 is externally fitted to and attached to the end of the outer ring 19 of the double row rolling bearing 17, and the other end of the seal boot 25. Between the end 27 of the drive shaft 2 and the peripheral surface of the drive shaft 2, the inner race 40, the ball 41 and the outer race 42.
Is provided, the inner race 40 of the single-row rolling bearing 43 is fitted to the drive shaft 2, and the other end 27 of the seal boot 25 is fitted to the outer race 42. The single row rolling bearing 43 is provided with a speed detecting device 30 for detecting the rotational speed of the drive shaft 2.

Incidentally, one end 26 of the seal boot 25 is externally fitted to and attached to the end of the outer ring 19 of the double row rolling bearing 17, and the other end 27 of the seal boot 25 and the drive shaft 2 are mounted.
By providing the single-row rolling bearing 43 with the peripheral surface of the seal boot 25, even when the drive shaft 2 rotates, the seal boot 25 does not rotate, so that the life of the seal boot 25 can be extended.

As shown in FIGS. 3 and 4, the speed detecting device 30 includes a pulsar ring as a detected member 32 and a Hall IC as a detecting member 33.
The detection member 33 is a so-called active type detection member 33.

The detected portion 32 is formed of a cylindrical plastic magnet 44 having N and S poles alternately arranged in the circumferential direction, and a non-magnetic material integrally polymerized on the inner peripheral surface thereof. And a base 45. The plastic magnet 44 is a well-known one, and is made of a magnetic metal material such as an injection molded product made of a synthetic resin mixed with magnetic powder or a sintered ferrite as a base material. It is manufactured by magnetizing the poles.

The Hall IC as the detection member 33 is
Although not shown in detail, the IC chip is molded with a protective cover made of synthetic resin. The protective cover of the detecting member 33 is provided with a rectangular parallelepiped main body 47 provided with an IC chip, and an L-shaped main body 47 connected substantially parallel to the main body 47 at a predetermined interval. It has a structure including a stopper 48 and is formed in a substantially U-shape in side view.

The IC chip is embedded in the detection member 33 so that the lower surface of the main body 47 is used as a sensor surface. Then, the protrusion 4 is provided at a predetermined position on the inner surface of the locking piece 48.
9 is formed, and a code line 35 for signal transmission is drawn out from the upper surface of the main body 47.

The detected member 32 includes a single-row rolling bearing 4.
3 is attached directly to the inner ring 40 of the
Numeral 3 is indirectly attached to the outer ring 42 of the single-row rolling bearing 43 at a predetermined position in the circumferential direction of the detected member 32 from a radial direction in a non-contact manner through a support ring 50 described later. .

As an example of a method of attaching the detected member 32, two layers of a base material 45, which is a non-magnetic base material to be a plastic magnet 44, and a base 45 are baked on the outer peripheral surface of the extension 51 of the inner ring 40. After that, the N pole and the S pole are alternately magnetized in a predetermined angular region in the circumferential direction of the base material, respectively. If the detected member 32 is directly attached to the outer peripheral surface of the inner ring 40 having high shape accuracy in this way, the detected member 32 is positioned with high accuracy in the radial direction. However, when the detected member 32 is printed on the inner race 40, it is necessary to consider the position in the axial direction.

The support ring 50 is provided with a single-row rolling bearing 43.
Of the outer ring 42, the single row rolling bearing 43 is attached to the detecting member 33 attached to the support ring 50.
The end of the inner ring 40 of the single row rolling bearing 43 is extended in the axial direction in consideration of the overhang dimension of the support ring 50 so that the detection member 32 directly attached to the inner ring 40 is radially opposed. The detection member 32 is attached to the outer peripheral surface of the extension portion 51.

The support ring 50 is formed of an annular iron plate press-molded in a plurality of stages. The support ring 50 is press-fitted to the inner peripheral surface of the end of the outer ring 42 of the single-row rolling bearing 43. A cylindrical portion 52, a first annular plate portion 53 rising radially outward from the first cylindrical portion 52, a second cylindrical portion 55 connected to an outer end of the first annular plate portion 53, Second annular plate portion 5 bent radially inward from cylindrical portion 55
4 and a third cylindrical portion 56 provided on the inner periphery of the second annular plate portion 54 and opposed to the extended portion 51 of the inner ring 40 of the single row rolling bearing 43 at a predetermined interval substantially in parallel with the extended portion 51. I have.

At one position in the circumferential direction of the second cylindrical portion 55, a sensor pocket 57 having an opening penetrating inward and outward in the radial direction is formed, and the second annular plate portion 54 has the same phase position as the sensor pocket 57. Is formed with a rectangular engaging hole 58 penetrating inward and outward in the axial direction. The opening shape of the engaging hole 58 is set so that the convex portion 49 of the detecting member 33 can be fitted.

The procedure for attaching the detection member 33 to the support ring 50 is as follows. The main body 47 of the detection member 33 is inserted from the radial direction into the sensor pocket 57 of the support ring 50 to support the main body 47 of the detection member 33. Between the first annular plate portion 53 and the second annular plate portion 54 of the annular body 50, and the locking piece 48 of the detection member 33 is arranged outside the second annular plate portion 54,
Subsequently, the detection member 33 is pushed in so that the projection 49 of the locking piece 48 is fitted into the engagement hole 58 of the support ring 50.

In such a state, since the main body 47 of the detecting member 33 is sandwiched between the first annular plate 53 and the second annular plate 54 of the support ring 50, the posture of the detecting member 33 is stabilized, Further, since the projection 49 of the locking piece 48 is engaged with the engagement hole 58 of the second annular plate portion 54, the detection member 33 can be securely held, and the detection member 33 can be moved in the axial direction and the radial direction. In addition, positioning can be performed with high accuracy in the circumferential direction.

After the detection member 33 is attached to the support ring 50 as described above, if the support ring 50 is attached along the axial end of the outer ring 42 of the single row rolling bearing 43, the detection member The sensor surface 33 faces the detected member 32 attached to the inner ring 40 of the single-row rolling bearing 43 with a predetermined gap in the radial direction. In this state, the gap between the detection target member 32 and the detection member 33 is positioned with high precision as described above, so that it can be managed with high precision. The detection member 33 may be attached before or after the support ring 50 is attached to the single-row rolling bearing 43. In order to remove the detection member 33 from the support ring 50, the worker deflects the lock piece 48 of the detection member 33 so that the protrusion 49 of the lock piece 48 engages the engagement hole 5 of the support ring 50.
Remove from step 8.

Next, a sealing device comprising a combination of a sealing member 59 and a slinger 60 is provided between the third cylindrical portion 56 formed on the support ring 50 and the extension 51 of the inner ring 40 of the single-row rolling bearing 43. 61 is attached. This sealing device 61
The seal member 59 is separately press-fitted on the support ring 50 side, and the slinger 60 is separately distributed on the inner ring 40 side of the single-row rolling bearing 43. Since the sealing device 61 is provided outside the detection member 33 in the support ring 50 in this manner, the opposing gap between the detected member 32 and the detecting member 33 is shielded, and foreign matter such as muddy water and sand is formed in the opposing gap. Can be prevented from entering.

The operation of the active type speed detector 30 will now be described. When the detected member 32 rotates synchronously with the rotation of the hub wheel 3, the magnetic poles of the detected member 32 sequentially face the non-rotating detecting member 33. Here, the direction of the magnetic field (lines of magnetic force) generated between the plural pairs of magnetic poles of the detected member 32 is alternately opposite along the circumferential direction. The direction of the magnetic field passing through the member 33 is sequentially reversed at a cycle corresponding to the rotation speed. Therefore, the detection member 33
Detects the periodic inversion of the direction of the magnetic field,
2 outputs a pulse signal having a frequency corresponding to the rotation speed.
This pulse signal is input to an ABS signal processing circuit (not shown), and the signal processing circuit performs processing on the wheel based on the pulse signal input from the detection member 33 and information such as the diameter of the wheel previously input. The rotation speed is recognized.

Then, only the detection member 33 is supported by the support ring 50.
, And the detection target member 32 is directly mounted on the inner ring 40 to be mounted. Therefore, the configuration can be simplified and the cost can be reduced, and the detection member 33 and the detection target can be detected. The displacement of the relative position with respect to the member 32 can be prevented, and the detection accuracy of the detection member 33 can be maintained at high accuracy.

Since the speed detecting device 30 is arranged separately from the double row rolling bearing 17 which generates heat when the vehicle is running, the speed detecting device 30 does not transmit heat from the double row rolling bearing 17 to the speed detecting device 30. Thus, the rotational speed of the drive shaft 2 (wheel) can be detected accurately over a long period of time.

Further, the detecting member 33 in the support ring 50
By providing the sealing device 61 further outside, the opposing gap between the detected member 32 and the detecting member 33 is shielded from the outside, so that foreign substances can be prevented from entering the opposing gap, and the detection accuracy by the detecting member 33 can be extended for a long time. Can be kept high over

Further, in consideration of the case where the inner race 40 of the single-row rolling bearing 43 to which the detection target member 32 is attached is made of a magnetic material, the detection target member 32 is formed of a plastic magnet 4.
4 and a base 45 made of a non-magnetic material, the inner ring 40 is formed by the plastic magnet 44.
Is prevented from being magnetized, so that the inner ring 40 is magnetized, and metal wear powder inside the single row rolling bearing 43 is removed by the inner ring 4.
The state in which the rolling characteristics of the ball 41 are hindered by attaching to the raceway groove of No. 0 and biting between the ball 41 and the inner ring 40 can be prevented.

Next, a third embodiment of the present invention will be described with reference to FIG. The wheel support structure 1 according to the third embodiment of the present invention includes an inner ring 40, a ball 41, and an outer ring 42 between the other end 27 of the seal boot 25 and the peripheral surface of the drive shaft 2.
A single-row rolling bearing 43 is provided. The inner race 40 of the single-row rolling bearing 43 is fitted to the drive shaft 2 and the outer race 42
Is fitted to the other end 27 of the seal boot 25.

Then, another single-row rolling bearing 65 is fitted to the drive shaft 2 adjacent to the single-row rolling bearing 43, and the other single-row rolling bearing 65 has the same structure as the embodiment shown in FIG. A speed detection device 30 having a similar configuration is provided.

The other configuration is the same as that of the second embodiment, so that detailed drawings and explanations are omitted. And also in the third embodiment of the present invention, the speed detection device 30
Since the single-row rolling bearing 65 is provided separately from the double-row rolling bearing 17 that generates heat when the vehicle travels, the speed detecting device 30 is not affected by the heat of the double-row rolling bearing 17, Therefore, the rotation speed of the drive shaft 2 can be accurately detected over a long period of time. Other functions and effects are the same as those of the second embodiment.

In the second embodiment, the speed detecting device 30 is provided on the single-row rolling bearing 43. In the third embodiment, another single-row rolling bearing is provided adjacent to the single-row rolling bearing 43. 65, but is not limited to this. Although not shown, a sliding bearing is provided in place of the single row rolling bearings 43 and 65, and the speed detecting device 30 is provided in the sliding bearing. You may. Also in this case, the heat of the double-row rolling bearing 17 is not transmitted to the speed detecting device 30 as in the above embodiments, and therefore, the rotational speed of the drive shaft 2 can be accurately detected over a long period of time.

In each of the above embodiments, a so-called active type detecting member 33 is used, but a passive type detecting member 33 may be used.

In the first embodiment, a rubber sheet having a large number of N poles and S poles alternately magnetized on its surface is used as the detection member 32. In the second and third embodiments, a plastic sheet is used. Although the magnet 44 is used, the present invention is not limited to this. Instead of providing the rubber sheet and the plastic magnet 44, the surface of the drive shaft 2 is subjected to serration processing, and the serrated portion is formed on the detected member 3.
The detection member 32 and the active type detection member 3 which are used as
3 to form a speed detecting device 30, and a detecting signal transmitted to a detected member 32 subjected to serration processing is detected by a detecting member 33. The rotation speed may be calculated.

[0050]

As is apparent from the above description, according to the present invention, the hub wheel on which the wheel is mounted is rotatably supported by rolling bearings, and the end of the drive shaft is connected to the hub wheel via a constant velocity joint. A seal boot for preventing foreign matter from entering the constant velocity joint is provided, and one end of the seal boot is fitted to the cylindrical surface of the constant velocity joint so as to fit the other end of the seal boot. Is disposed so as to fit around the peripheral surface of the drive shaft, and at a position near the other end of the seal boot, a speed detection device for detecting the rotation speed of the drive shaft is provided. Since the speed detecting device is disposed away from the rolling bearing, even if the rolling bearing generates heat during running of the vehicle, the speed detecting device is not affected by heat, and therefore, can be accurately and reliably obtained for a long time. Wheel rotation speed It can detect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an overall configuration of a wheel support structure according to a first embodiment of the present invention.

FIG. 2 is a schematic sectional view of a wheel support structure according to a second embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of the speed detection device.

FIG. 4 is an exploded perspective view of the same.

FIG. 5 is a sectional view of a wheel support structure according to a third embodiment of the present invention.

FIG. 6 is a sectional view of a conventional wheel support structure.

FIG. 7 is an enlarged cross-sectional view of the speed detection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wheel support structure 2 Drive shaft 3 Hub wheel 4 Constant velocity joint 17 Double row rolling bearing 18 Inner ring 19 Outer ring 20 Ball 22 Knuckle 25 Seal boot 30 Speed detector 32 Detected member 33 Detecting member 35 Code line

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G01P 3/487 G01P 3/487 C

Claims (3)

[Claims] 1. A hub wheel for supporting a wheel is attached to an end of a drive shaft via a constant velocity joint. A rolling bearing is mounted on the hub wheel, and an outer ring of the rolling bearing, a vehicle body, Is fixed via a supporting member, and a seal boot for preventing foreign matter from entering the constant velocity joint is provided, and one end of the seal boot has a cylindrical portion peripheral surface of the constant velocity joint. The other end of the seal boot is fitted to the outside, and the other end of the seal boot is a wheel support structure arranged so as to be fitted over the peripheral surface of the drive shaft, at a position near the other end of the seal boot, A wheel supporting structure, further comprising a speed detecting device for detecting a rotation speed of the drive shaft. 2. The wheel support structure according to claim 1, wherein the speed detecting device includes a detected member that rotates together with the drive shaft, and a detecting member that is disposed to face the detected member. . 3. A bearing is provided between the peripheral surface of the drive shaft and the other end of the seal boot. A member to be detected of a speed detecting device is attached to an inner ring of the bearing, and a member to be detected is attached to an outer ring of the bearing. The wheel support structure according to claim 1, wherein a detection member of the speed detection device is attached to face the detection member.