JP2011174571A - Wheel supporting bearing unit with rotating speed sensing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel supporting bearing unit equipped with a rotating speed sensing device in which a dimensional change of bearings and a cost increase are suppressed, the rotating speed can be sensed without altering the internal specifications of the bearing and the ease of handling can be maintained without increasing the number of component parts. <P>SOLUTION: The bearing unit 10 supporting a vehicle wheel is furnished with a pair of tapered roller bearings 20, 20 and the rotating speed sensing device 30. The encoder 31 of the rotating speed sensing device 30 is composed of a notch 21b formed at the end face in axial direction of the outer ring 21. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a wheel support bearing unit with a rotational speed detection device, and more specifically, rotation applied to a vehicle having a large load such as a large truck or a dump truck, particularly a vehicle used in a mine mining site or the like. The present invention relates to a wheel supporting bearing unit with a speed detecting device.

  Tapered roller bearings having a large load capacity are generally used as bearings for supporting the wheels of vehicles such as large trucks and dump trucks that have a large in-vehicle load. In addition, these vehicles are sometimes used at mining sites, but the roads at such sites are often not maintained. For this reason, the bearings used in these vehicles may receive impact loads due to road swells and obstacles, resulting in indentations on the raceway surface. Further, when the vehicle travels on a puddle on a road where the vehicle is not maintained, water enters the bearing, resulting in poor lubrication inside the bearing. Then, peeling occurs in the bearing that has caused indentation or poor lubrication, and in the worst case, the bearing cannot rotate and the vehicle slips.

  In order to detect the above-described slip, it has been devised that a rotational speed detection device is attached to a vehicle having a large load. (See Patent Document 1). In the tapered roller bearing described in Patent Document 1, a tone wheel is fitted and fixed to the cylindrical surface of the inner ring, and the rotation speed is detected by a sensor attached to the outer ring. Further, as an apparatus for detecting the rotational speed, an encoder is devised which is composed of permanent magnets in which S poles and N poles are alternately arranged at equal intervals in the circumferential direction on the axial end face of the cage. (For example, refer to Patent Document 2). Furthermore, an apparatus has been devised in which S poles and N poles are alternately embedded in the end face in the axial direction of the roller, and the slip of the bearing is detected based on the rotation speed of the roller (see, for example, Patent Document 3). ).

JP-A-7-260815 JP 2005-180985 A JP-A-8-277836

  By the way, in the detection apparatus of patent documents 1 to 3, since a tone wheel and a magnetic encoder were incorporated in a bearing, the number of parts increased and the bearing was subject to space restrictions and the cost increased.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to detect the rotational speed without changing the internal specifications of the bearing, and to maintain the handleability without increasing the number of parts. Another object of the present invention is to provide a wheel support bearing unit with a rotational speed detection device that suppresses changes in bearing dimensions and cost.

The above object of the present invention can be achieved by the following constitution.
(1) An outer ring that can be fitted to a hub wheel to which the wheel is attached, an inner ring that can be fitted to the shaft, a plurality of tapered rollers that are arranged to roll between the outer ring and the inner ring, and a circumferential direction A pair of tapered roller bearings, each having a plurality of pockets for holding the plurality of tapered rollers, respectively, and arranged in a rear combination with each other,
An encoder configured by any one of the outer ring, the cage, and the plurality of tapered rollers, which changes the characteristics of the surface to be detected in the circumferential direction, and detects the rotational speed of the encoder facing the encoder. And a rotational speed detection device attached to at least one of the pair of tapered roller bearings,
A wheel support bearing unit with a rotational speed detection device.
(2) The wheel support bearing unit with a rotational speed detection device according to (1), wherein the encoder is configured by a notch formed in an axial end surface of the outer ring.
(3) The wheel support bearing unit with a rotation speed detection device according to (1), wherein the encoder is configured by a notch formed in an axial end surface of the cage.
(4) The wheel support bearing unit with a rotational speed detection device according to (1), wherein the encoder is configured by magnetizing the plurality of tapered rollers.
(5) The sensor is attached to an annular ring member fixed to the inner ring, and
The wheel support bearing unit with a rotational speed detection device according to any one of (1) to (4), wherein a key is fitted between the inner ring and the shaft.

  According to the wheel support bearing unit with a rotational speed detection device of the present invention, the encoder is configured by any one of the outer ring, the cage, and the plurality of tapered rollers, so that the internal specification of the bearing is not changed. Rotational speed can be detected, handling properties can be maintained without increasing the number of parts, and bearing size changes and cost increases can be suppressed.

It is a half sectional view showing a bearing unit for wheel support with a rotation speed detection device concerning a 1st embodiment of the present invention. It is sectional drawing of the tapered roller bearing of FIG. 1, and a rotational speed detection apparatus. It is sectional drawing of the tapered roller bearing of the wheel support bearing unit with a rotational speed detection apparatus which concerns on 2nd Embodiment of this invention, and a rotational speed detection apparatus. It is a perspective view which shows the holder | retainer of FIG. It is sectional drawing of the tapered roller bearing of the wheel support bearing unit with a rotational speed detection apparatus which concerns on 3rd Embodiment of this invention, and a rotational speed detection apparatus. It is sectional drawing of the tapered roller bearing and rotational speed detection apparatus which show the modification of the ring member which attaches the sensor of this invention.

  Hereinafter, a wheel support bearing unit with a rotational speed detection device according to each embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 shows a wheel support bearing unit with a rotation speed detection device applied to a vehicle such as a large truck or a dump truck. In this bearing unit 10, a hub wheel 11 to which a wheel (not shown) is attached is rotatably supported on a shaft 12 via a pair of tapered roller bearings 20 and 20.

  As shown in FIGS. 1 and 2, the pair of tapered roller bearings 20 and 20 are fitted into the hub wheel 11, respectively, and an outer ring 21 in which a conical outer ring raceway surface 21 a is formed on the inner peripheral surface, and a shaft 12. And a plurality of tapered rollers 23 that are rotatably arranged between the outer ring 21 and the inner ring 22, and a circumferential direction. And retainers 24 each having a plurality of pockets 24a that are formed at predetermined intervals and hold the plurality of tapered rollers 23, respectively. The shaft 12 and the inner ring 22 are formed with key grooves 12a and 22b, respectively, and the creep phenomenon is prevented by fitting the key 13 into each key groove 12a and 22b.

  Further, the tapered roller bearing 20 disposed on the vehicle outer side is provided with a rotational speed detection device 30 that detects the rotational speed of the outer ring 21. As shown in FIG. 2, the rotational speed detection device 30 detects the rotational speed of the outer ring 21 in opposition to the encoder 31 that changes the characteristics of the surface to be detected alternately and at equal intervals in the circumferential direction. And a sensor 32. The encoder 31 is configured to be uneven by a plurality of notches 21 b formed at predetermined intervals on the axial end surface of the outer ring 21. The sensor 32 is attached to the inner ring 22 via an annular ring member 33 attached to a bolt hole 22c provided in the inner ring 22 by a bolt 34, and faces the notch 21b.

  Although not shown, the sensor 32 is a passive sensor including a permanent magnet, a pole piece made of a magnetic material, and a coil wound around the pole piece. In the sensor 32, the density of the magnetic flux passing through the pole piece changes as the distance between the unevenness of the encoder 31 and the pole piece changes, and the electromotive force induced in the coil wound around the pole piece changes. Thus, the rotational speed of the outer ring 21 is detected.

  According to the wheel support bearing unit 10 with the rotational speed detection device configured as described above, the encoder 31 is configured by the outer ring 21, and thus the encoder 31 is configured without changing the internal specification of the tapered roller bearing 20. The rotational speed of the outer ring 21 can be detected, handling is maintained without increasing the number of parts, and changes in bearing dimensions and cost increases can be suppressed.

  Further, since the encoder 31 is constituted by the notch 21b formed on the axial end surface of the outer ring 21, the sensor 32 can directly detect the rotational speed of the outer ring 21.

  Furthermore, since the sensor 32 is attached to the annular ring member 33 fixed to the inner ring 22, the ring member 33 is fixed to the inner ring 22 with high rigidity, and the sensor 32 can be firmly fixed. Further, since the key 14 is fitted between the inner ring 22 and the shaft 12, it is possible to prevent the position shift of the sensor 32 due to the creep phenomenon of the inner ring 22.

  In addition, although the encoder 31 of this embodiment is comprised by forming the notch 21b in the outer ring | wheel 21, you may make it the axial direction end surface of the outer ring | wheel 21 comprise a magnetic encoder.

(Second Embodiment)
FIG. 3 is a cross-sectional view of a tapered roller bearing and a rotational speed detection device of a wheel support bearing unit with a rotational speed detection device according to a second embodiment of the present invention, and FIG. 4 is a diagram of a retainer of the tapered roller bearing. It is a perspective view. In this rotational speed detection device 30, the encoder 31 is configured to be uneven by a plurality of notches 24 b formed at predetermined intervals in the circumferential direction on the axial end surface of the cage 24. In addition, the retainer 24 has a function as the encoder 31, and thus is made of a magnetic material. In this case, the revolution number of the cage 24 detected by the sensor 32 is converted into the rotation number of the outer ring 21 by a control unit (not shown).

  Therefore, even when the encoder 31 is configured by the holder 24 as in the present embodiment, the same effects as in the first embodiment can be obtained.

(Third embodiment)
FIG. 5 is a cross-sectional view of a tapered roller bearing and a rotation speed detection device of a wheel support bearing unit with a rotation speed detection device according to a third embodiment of the present invention. In this rotational speed detection device 30, the encoder 31 is configured by magnetizing a plurality of tapered rollers 23, and the sensor 32 is an active type equipped with a magnetic detection element such as a Hall IC or a magnetoresistive element. Configure the sensor. In this case, the revolution number of the tapered roller 13 detected by the sensor 32 is converted into the rotation number of the outer ring 21 by a control unit (not shown).

  Therefore, even when the encoder 31 is configured by the tapered roller 23 as in the present embodiment, the same effects as in the first embodiment can be obtained.

  In addition, this invention is not limited to the said embodiment, A change, improvement, etc. are possible suitably. Moreover, each structure of the said embodiment is applicable in combination in the range which can be implemented.

  For example, in this embodiment, the annular ring member 33 to which the sensor 32 is attached is fixed by the bolt 34, but the attachment method is not particularly limited as long as it can be firmly fixed to the inner ring 22. For example, as shown in FIG. 6, the ring member 33 is fixed to the inner ring 22 by fitting a wedge 33 a formed on the radially inner side of the ring member 33 into a groove 22 d formed on the outer peripheral surface of the inner ring 22. Alternatively, the ring member 33 may be fixed to the inner ring 22 by direct press-fitting.

In the present invention, a load sensor may be attached instead of the rotation speed sensor, and slip may be detected by the load sensor. A slip sensor may be detected by providing a vibration sensor and a temperature sensor.
In addition, a slip may be detected by combining at least two sensors of a speed sensor, a load sensor, a vibration sensor, and a temperature sensor.

  In the present embodiment, the rotational speed sensor is attached to the tapered roller bearing arranged on the outside of the vehicle, but may be attached to the tapered roller bearing arranged on the inside of the vehicle.

10 Wheel support bearing unit with rotational speed detector
DESCRIPTION OF SYMBOLS 11 Hub wheel 12 Shaft 20 Tapered roller bearing 21 Outer ring 21b Notch 22 Inner ring 23 Tapered roller 24 Cage 24b Notch 30 Speed detector 31 Encoder 32 Sensor

Claims (5)

An outer ring that can be fitted into a hub wheel to which the wheel is attached, an inner ring that can be fitted to a shaft, a plurality of tapered rollers that are arranged to roll between the outer ring and the inner ring, and a predetermined circumferential direction. A pair of tapered roller bearings that are formed at intervals and each have a plurality of pockets that respectively hold the plurality of tapered rollers, and that are arranged in a backside combination with each other;
An encoder configured by any one of the outer ring, the cage, and the plurality of tapered rollers, which changes the characteristics of the surface to be detected in the circumferential direction, and detects the rotational speed of the encoder facing the encoder. And a rotational speed detection device attached to at least one of the pair of tapered roller bearings,
A wheel support bearing unit with a rotational speed detection device.   The wheel support bearing unit with a rotation speed detection device according to claim 1, wherein the encoder is configured by a notch formed in an axial end surface of the outer ring.   The wheel support bearing unit with a rotation speed detection device according to claim 1, wherein the encoder is configured by a notch formed in an axial end surface of the cage.   The wheel support bearing unit with a rotation speed detection device according to claim 1, wherein the encoder is configured by magnetizing the plurality of tapered rollers. The sensor is attached to an annular ring member fixed to the inner ring, and
The wheel support bearing unit with a rotational speed detection device according to any one of claims 1 to 4, wherein a key is fitted between the inner ring and the shaft.

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