JPH0826084A - Rolling bearing unit equipped with revolition speed detecting device - Google Patents

Abstract

PURPOSE:To improve reliability in the detection of the revolution speed and prevent the breakage of a rolling body, by forming a plurality of thin parts in the small diame ter part of tone wheel in the equal intervals in the circumferential direction, externally fitting-fixing a large diameter part at the end part of an inner wheel, and allowing a stage part to collide with the end edge of the inner wheel. CONSTITUTION:Even if a tone wheel 22 is pushed towards an inner wheel member 4 after the tone wheel 22 is installed on the inner wheel member 4, the edge of a large diameter part 24 is prevented from intruding to the second inner wheel orbit 2b part, because of the engagement between a stage part 25 and the inner wheel member 4. Accordingly, the rolling surfaces of the rolling bodies 10 and 10 are prevented from being damaged by the tone wheel 22. The thickness dimension over in the diameter direction of the space part which exists between the outer peripheral surface of a small diameter part 22 and the inner peripheral surface of a cover 27 can be increased, and a relatively large sensor 14 can be installed in the space part. Accordingly, the output of the sensor 14 can be increased by the portion for the increase in the dimension of the sensor 14.

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 is used for rotatably supporting a vehicle wheel on a suspension device and for detecting the rotation speed of the wheel.

[0002]

2. Description of the Related Art An automobile wheel is rotatably supported by a suspension system and the rotational speed of the wheel is detected in order to control an antilock brake system (ABS) or a traction control system (TCS). As a rolling bearing unit with a rotation speed detecting device for carrying out the above, for example, Japanese Utility Model Laid-Open No. 3-99676 discloses a structure as shown in FIG.

The rolling bearing unit with a rotation speed detecting device shown in FIG. 4 has a flange portion 1 for fixing a wheel at an outer end portion (a left end portion in FIG. 4) and a first inner ring on an outer peripheral surface of an intermediate portion. The hub 3 having the raceway 2a and the second inner ring raceway 2 on the outer peripheral surface
b, which is externally fitted to the outer peripheral surface of the intermediate portion of the hub 3, and is screwed to the male screw portion 5 formed on the outer peripheral surface of the inner end portion (right end portion in FIG. 4) of the hub 3. , A nut 6 for pressing the inner end surface of the inner ring member 4 in accordance with the screwing and fixing the inner ring member 4 at a predetermined position on the outer peripheral surface of the hub 3, and a mounting portion 7 for supporting a suspension device (not shown). An outer ring member 9 which is provided on the outer peripheral surface and has double rows of outer ring raceways 8a and 8b formed on the inner peripheral surface;
It has a plurality of rolling elements 10 and 10 provided between the hub 3 and the outer ring member 9. Then, the hub 3 for fixing the wheels is rotatably supported inside the outer ring member 9 supported by the suspension device.

A base end portion (left end portion in FIG. 4) of a cylindrical tone wheel 11 is externally fitted and fixed to an inner half portion of the inner ring member 4. On the inner end surface of the first half portion (right half portion in FIG. 4) of the tone wheel 11, a plurality of cutouts, which are thinned portions, are formed at equal intervals in the circumferential direction. The outer peripheral surface of the first half of the tone wheel 11 is covered with a reinforcing material 12 made of a non-magnetic material. Further, in the inner end opening of the outer ring member 9,
A sensor 14 is fixed to the cover 13 mounted in a state of covering the opening, and the tip end of the sensor 14 is opposed to the inner peripheral surface of the first half of the tone wheel 11.

When the rolling bearing unit with the rotational speed detecting device as described above is used, the wheel fixed to the flange portion 1 provided at the outer end portion of the hub 3 is mounted on the suspension device supporting the outer ring member 9. Support rotatably. Further, when the tone wheel 11 fitted and fixed to the inner ring member 4 rotates with the rotation of the wheel, the output of the sensor 14 facing the portion where the plurality of cutouts are formed in the first half of the tone wheel 11 changes. To do. Since the frequency at which the output of the sensor 14 changes is proportional to the rotation speed of the wheel, if the output signal of the sensor 14 is input to a controller (not shown), the rotation speed of the wheel can be obtained and the ABS or TCS can be appropriately controlled. .

[0006]

However, in the case of the conventional rolling bearing unit with a rotation speed detecting device which is constructed and operates as described above, there are the following points to be solved. That is, in the case of the conventional structure shown in FIG. 4, since the cylindrical tone wheel 11 is simply fitted onto the inner ring member 4,
There is a possibility that the installation position of the tone wheel 11 may be carelessly displaced. For example, in the process of manufacturing a rolling bearing unit with a rotation speed detecting device, after the tone wheel 11 is assembled and before the cover 13 is mounted, the tip end of the tone wheel 11 hits any article, the tone wheel 11 The mounting position may be displaced in the axial direction (left and right direction in FIG. 4), or the center axis of the tone wheel 11 and the center axis of the hub 3 may not coincide with each other. In this way, if the mounting position of the tone wheel 11 is displaced, the original function of the rotation speed detection device cannot be exerted.

When the edge of the tone wheel 11 pushed in the axial direction interferes with the rolling elements 10 and 10, the rolling surfaces of the rolling elements 10 and 10 are damaged, There is also a possibility that the life of the rolling bearing unit part may be significantly reduced.

Further, the tone wheel 11, which is formed in a simple cylindrical shape, is relatively easily deformed by the force in the diametrical direction. Therefore, the distance between the outer peripheral surface of the tone wheel 11 and the sensor 14 changes due to vibration or the like generated when the vehicle is running or braking, and an output irrelevant to the rotation speed is generated, so that the correct rotation speed can be detected. It may disappear. The rolling bearing unit with a rotation speed detecting device of the present invention was invented in view of such circumstances.

[0009]

A rolling bearing unit with a rotation speed detecting device according to the present invention has a non-rotating outer ring having an outer ring raceway on its inner peripheral surface, like the above-described conventional rolling bearing unit with a rotating speed detecting device. An inner ring that has an inner ring raceway on its outer peripheral surface and that rotates during use; a plurality of rolling elements provided between the outer ring raceway and the inner ring raceway; and a magnetic material that is supported by the inner ring and rotates during use. And a cylindrical tone wheel, and a non-rotating sensor that is supported by the outer ring and faces the outer peripheral surface of the tone wheel.

Particularly, in the rolling bearing unit with a rotation speed detecting device of the present invention, the tone wheel is such that the small diameter portion and the large diameter portion, which are concentric with each other, are continuous at the step portion, and the small diameter portion is the same. A plurality of thinned portions are formed in the circumferential direction at equal intervals. The large-diameter portion is externally fitted and fixed to the end portion of the inner ring, and the step portion abuts on the end edge of the inner ring.

[0011]

When the rolling bearing unit with a rotation speed detecting device of the present invention constructed as described above rotatably supports a wheel or the like fixed to the inner ring, and when detecting the rotation speed of the inner ring. The operation of is similar to that of the conventional structure described above. In particular, in the case of the rolling bearing unit with a rotation speed detecting device of the present invention, the step portion that connects the small diameter portion and the large diameter portion forming the tone wheel is in contact with the edge of the inner ring, so that the tone wheel Even if the tip collides with another article, the mounting position of the tone wheel will not be displaced, and it is possible to prevent deterioration of detection accuracy due to defective mounting position. Further, the tone wheel and the rolling elements do not interfere with each other, and it is possible to prevent deterioration of durability due to damage of the rolling surface.
Further, due to the presence of the stepped portion, the rigidity of the tone wheel with respect to the force over the diametrical direction is larger than that of a simple cylindrical tone wheel. Therefore, the distance between the outer peripheral surface of the tone wheel and the sensor does not change regardless of the rotation speed, and the correct rotation speed can be detected.

[0012]

1 and 2 show a first embodiment of the present invention. A flange portion 1 for fixing a wheel is formed on an outer peripheral surface of the hub 3 (which is an end portion which is an outer side in the width direction when assembled to a vehicle, and is a left end portion in FIG. 1), and an intermediate portion. A first inner ring raceway 2a and a step portion 15 are formed on the outer peripheral surface. Further, a state in which an inner ring member 4 having a second inner ring raceway 2b formed on the outer peripheral surface of the hub 3 and an outer end surface (the left end surface in FIG. 1) of the inner ring member 4 is abutted against the step portion 15 So, it is supported by external fitting. The first inner ring raceway 2a is formed on an inner ring member (not shown) separate from the hub 3, instead of being formed directly on the outer peripheral surface of the hub 3, and the inner ring member and the inner ring member 4 are connected to each other. Can also be externally fitted and fixed to the hub 3.

A male screw portion 1 is provided on a portion near the inner end of the hub 3.
6 is formed. The inner ring member 4 is fixed to a predetermined portion of the outer peripheral surface of the hub 3 by screwing a nut 6 into the male screw portion 16 and further tightening the nut 6. A mounting portion 7 for fixing the outer ring member 9 to the suspension device is provided on the outer peripheral surface of the intermediate portion of the outer ring member 9 arranged around the hub 3. Further, on the inner peripheral surface of the outer ring member 9, the outer ring raceways 8a and 8b respectively face the first and second inner ring raceways 2a and 2b.
Is formed. Then, the first and second inner ring raceways 2a,
A plurality of rolling elements 10 and 10 are provided between 2b and the pair of outer ring raceways 8a and 8b, respectively, so that the hub 3 can freely rotate inside the outer ring member 9.

A seal ring 17 is mounted between the inner peripheral surface of the outer end portion of the outer ring member 9 and the outer peripheral surface of the hub 3 so that the inner peripheral surface of the outer ring member 9 and the outer peripheral surface of the hub 3. And the outer end opening of the space where the plurality of rolling elements 10 and 10 are provided is closed. Further, at the inner end portion of the inner ring member 4 (referred to as the end portion that is closer to the center in the width direction when assembled to a vehicle, the right end portion in FIGS. 1 and 2), a tone is formed at a portion deviated from the second inner ring raceway 2 b. The base end portion (the left end portion in FIGS. 1 and 2) of the wheel 22 is externally fitted and fixed. This tone wheel 22
Is formed of a magnetic metal plate such as a steel plate in a cylindrical shape as a whole. Further, the tone wheel 22 is composed of a small-diameter portion 23 and a large-diameter portion 24, which are concentrically formed with each other, connected by a step portion 25.

In such a tone wheel 22, the large diameter portion 24 is fitted onto the outer peripheral surface of the inner end portion of the inner ring member 4, and the step portion 25 is brought into contact with the inner end edge portion of the inner ring member 4. In the state
The inner ring member 4 is supported and fixed. Therefore, the small diameter portion 23 is supported concentrically with the inner ring member 4. And
In this small-diameter portion 23, through-holes 26 or cut-out portions such as notches are formed in the circumferential direction at equal intervals. Each through hole 26
Have the same shape, for example, a rectangular shape that is long in the axial direction (the horizontal direction in FIGS. 1 and 2). The inner ring member 4 and the hub 3 to which the inner ring member 4 is externally fitted and fixed correspond to the inner ring described in the claims.

On the other hand, the inner end opening of the outer ring member 9 is covered by the cover 2.
Blocking with 7 prevents the entry of dust and rainwater into the outer ring member 9 from the inner end opening. This cover 27
Is made by drawing a metal plate such as a stainless steel plate. An outer end portion of the cover 27 is opened, and a flange-shaped locking protrusion 28 is provided on a portion of the outer peripheral surface near the opening. The outer diameter of the opening of the cover 27 in the free state is equal to or slightly larger than the inner diameter of the inner end opening of the outer ring member 9. As a result, the portion of the cover 27 near the opening can be fitted in the inner end opening of the outer ring member 9 until the locking projection 28 hits the inner end surface of the outer ring member 9.

The sensor 14 is provided in the cover 27.
Is held and fixed in a state where the position is regulated. The output signal of the sensor 14 is taken out through a lead wire (not shown) connected to a connector 29 provided on the outer surface of the cover 27. The detecting portion 30 of the sensor 14 faces inward in the diameter direction of the cover 27. This detection unit 30
With the cover 27 fitted and fixed to the inner end portion of the outer ring member 9, 0.5 to 1.0 is formed on the outer peripheral surface of the small diameter portion 23.
It opposes via a minute gap 31 of about mm.

The rolling bearing unit with a rotation speed detecting device of the present invention configured as described above rotatably supports the wheel with respect to the suspension device and rotates the wheel fixed to the flange portion 1 of the hub 3. The operation itself at the time of detecting the speed is the same as that of the above-described conventional rolling bearing unit with a rotation speed detecting device.

Particularly, in the case of the rolling bearing unit with the rotation speed detecting device of the present invention, the step portion 25 which connects the small diameter portion 23 and the large diameter portion 24 forming the tone wheel 22 abuts the inner end edge of the inner ring member 4. Therefore, even if a portion of the tip end portion of the tone wheel 22 protruding from the inner end opening of the outer ring member 9 collides with another article during the assembly of the rolling bearing unit with the rotation speed detecting device, this tone is generated. The mounting position of the wheel 22 will not be displaced. As a result, it is possible to prevent defective products due to defective mounting of the tone wheel 22, and to improve the product yield.

Further, the axial dimension of the large-diameter portion 24 is smaller than the axial dimension of the portion (shoulder portion) of the inner end portion of the inner ring member 4 which deviates from the second inner ring raceway 2b. Therefore, the edge of the large diameter portion 24 does not interfere with the rolling elements 10 and 10. That is, the tone wheel 22 is connected to the inner ring member 4
After the tone wheel 22 is attached to the inner ring member 22
Even when it is pushed toward, the step 25 and the inner ring member 4
Due to the engagement with the inner end edge of the above, the end edge of the large diameter portion 24 does not enter the portion of the second inner ring raceway 2b. Therefore, the rolling surfaces of the rolling elements 10, 10 are not damaged by the tone wheel 22, and the durability of the rolling bearing unit can be sufficiently ensured.

Further, due to the existence of the stepped portion 25, the rigidity of the tone wheel 22 against the force in the diametrical direction is the same as that of the simple tone wheel 11 (FIG. 4) which is the same as that incorporated in the above-mentioned conventional structure. Big compared to. For this reason, the tone wheel 22 is affected by the vibration during traveling or braking.
Is not deformed, and the distance between the outer peripheral surface of the tone wheel 22 and the detection portion 30 of the sensor 14 (the thickness of the minute gap 31) does not change regardless of the rotation speed. As a result, the correct rotation speed can be detected regardless of the above-mentioned vibrations during traveling and braking.

Further, the outer diameter of the small-diameter portion 23 having the original function of the tone wheel 22 is larger than the outer diameter of the tone wheel 11 (FIG. 4) incorporated in the above-mentioned conventional structure by the step difference of the step 25. Can be made smaller. Therefore, this small diameter portion 2
The thickness of the space existing between the outer peripheral surface of No. 3 and the inner peripheral surface of the cover 27 in the diametrical direction can be increased, and a relatively large sensor 14 can be mounted in this space. As the sensor 14 can be made larger, the output of the sensor 14 can be increased and the reliability of the rotation speed detection can be improved.

Next, FIG. 3 shows a second embodiment of the present invention. In the case of this embodiment, the tone wheel 22a is set to 2
By narrowing down the steps, the diameter of the small diameter portion 23a is made smaller than in the case of the first embodiment described above. Then, as the diameter of the small diameter portion 23a is reduced in this way,
The thickness dimension of the sensor 14 in the diameter direction (vertical direction in FIG. 3) is increased. Therefore, in the case of the present embodiment, the output of the sensor 14 can be increased and the reliability of the rotation speed detection can be improved more than in the case of the first embodiment described above.

The tone wheel constituting the rolling bearing unit with the rotation speed detecting device of the present invention can be manufactured by pressing a metal plate, which has a low processing cost, or by sintering. Further, in each of the illustrated embodiments, since the present invention is applied to the bearing unit for supporting the non-driving wheels (the front wheels of the FR vehicle and the rear wheels of the FF vehicle), the sensor 14 is supported. The cover 27 has a shape in which its inner end is sealed. However, the present invention is not limited to such bearing units for non-driving wheels, but can also be applied to bearing units for driving wheels (rear wheels of FR vehicles, front wheels of FF vehicles). When the present invention is applied to the bearing unit for the drive wheels as described above, the cover is formed in a circular ring shape, and a circular hole for inserting a part of the constant velocity joint is provided in the central portion thereof. Further, the hub is formed into a cylindrical shape, and a female spline groove for engaging with the male spline groove on the outer peripheral surface of the drive shaft is formed on the inner peripheral surface thereof.

[0025]

Since the rolling bearing unit with the rotational speed detecting device of the present invention is constructed and operates as described above,
It is possible to obtain a structure in which the detection accuracy is excellent and the rolling bearing unit portion has excellent durability.

[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 sectional view showing an example of a conventional structure.

[Explanation of symbols]

 1 Flange 2a 1st inner ring raceway 2b 2nd inner ring raceway 3 Hub 4 Inner ring member 5 Male screw part 6 Nut 7 Attachment part 8a, 8b Outer ring raceway 9 Outer ring member 10 Rolling element 11 Tone wheel 12 Reinforcing material 13 Cover 14 Sensor 15 Step portion 16 Male screw portion 17 Seal ring 22, 22a Tone wheel 23, 23a Small diameter portion 24 Large diameter portion 25 Step portion 26 Through hole 27 Cover 28 Locking protrusion 29 Connector 30 Detection portion 31 Small gap

Claims (1)

[Claims] 1. A non-rotating outer ring having an outer ring raceway on an inner peripheral surface, an inner ring having an inner ring raceway on an outer peripheral surface and rotating at the time of use, and a plurality of rolling elements provided between the outer ring raceway and the inner ring raceway. Rotation speed including a moving body, a cylindrical tone wheel made of a magnetic material, which is supported by the inner ring and rotates during use, and a non-rotating sensor which is supported by the outer ring and faces the outer peripheral surface of the tone wheel. In the rolling bearing unit with a detection device, the tone wheel is one in which a small-diameter portion and a large-diameter portion that are concentric with each other are continuous in steps.
A plurality of thinned portions are formed in the small diameter portion at equal intervals in the circumferential direction, the large diameter portion is externally fitted and fixed to the end portion of the inner ring, and the step portion is A rolling bearing unit with a rotation speed detection device, which is in contact with the edge of the inner ring.