JP2008203130A - Bearing for wheel with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing for a wheel with a sensor that can easily mount a sensor, and can accurately detect the load and the rotation acting on the bearing by only mounting one type of sensor. <P>SOLUTION: In this bearing for the wheel having a plurality of rows of rolling bodies 5 interposed between an outer member 1 and an inner member 2, the rotation-side member, of the outward member 1 and inward member 2, is provided with a ring-like pulsar ring 16, where a plurality of teeth are arranged in the circumferential direction of the rotation-side member. The fixed-side member, of the outward member 1 and inward member 2, is provided with sensors 18A and 18B for detecting the pulsar ring 16. The bearing comprises a rotation speed detecting means 20 for detecting the rotation speed from the period of the output signals from the sensors 18A and 18B, and a load detecting means 21 for detecting the load acting on the bearing for the wheel from the length of the amplitude of the output signals from the sensors 18A and 18B or the phase difference between the input signal and the output signals. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sensor-equipped wheel bearing incorporating a sensor for detecting a load applied to a wheel bearing portion and rotation of the wheel.

  2. Description of the Related Art Conventionally, there is a wheel bearing provided with a sensor for detecting the rotational speed of each wheel for safe driving of an automobile. Conventional measures to ensure driving safety of general automobiles are performed by detecting the rotational speed of the wheels of each part, but the rotational speed of the wheels is not sufficient, and it is further safer by using other sensor signals. It is required that the surface can be controlled.

  Therefore, it is conceivable to control the posture from the load acting on each wheel during vehicle travel. For example, a large load is applied to the outer wheel in cornering, and the load applied to each wheel is not uniform. In addition, even when the load is uneven, the load applied to each wheel is uneven. For this reason, if the load applied to the wheel can be detected at any time, the suspension control etc. is controlled in advance based on the detection result, thereby controlling the attitude during vehicle travel (preventing rolling during cornering, preventing the front wheel from sinking during braking, It is possible to prevent subsidence due to uneven load capacity. However, there is no appropriate installation location of a sensor that detects a load acting on the wheel, and it is difficult to realize posture control by load detection.

  In addition, when steer-by-wire is introduced in the future and the system becomes a system in which the axle and the steering are not mechanically coupled, it is required to detect the axle direction load and transmit the road surface information to the handle held by the driver.

As a response to such a demand, a wheel bearing has also been proposed in which a gap (relative displacement) between a rotating wheel and a fixed ring of a bearing is measured using a displacement sensor and a load is calculated therefrom (for example, Patent Document 1). , 2). There has also been proposed a wheel bearing in which an ultrasonic sensor is provided on the outer ring of the bearing and the load is detected based on an echo ratio that varies depending on the contact area between the rolling element and the rolling surface (for example, patent documents 3 and 4).
JP 2004-003918 A Japanese Patent Laid-Open No. 2004-232795 JP 2006-177932 A JP 2006-292027 A

However, the techniques disclosed in Patent Documents 1 and 2 have the following problems.
・ The relative displacement between the rotating wheel and the fixed wheel is small, making it difficult to detect the displacement.
・ In order to measure loads in various directions, it is necessary to install multiple sensors. For example, when a sensor is installed in a direction perpendicular to the ground contact surface of the tire, a vertical displacement can be detected, but a horizontal displacement cannot be detected.
・ In the eddy current method and the method of detecting the gap by the magnitude of the magnetic flux, the gap between the detection unit and the detection unit must be narrowed.
・ In the case of an optical displacement sensor, it is vulnerable to vibration.
-The displacement sensor in this case is a dedicated sensor for load detection. If rotation detection is to be performed in addition to load detection, it is necessary to provide a separate rotation sensor. Although it is possible to determine the rotation of the wheel from the revolution speed detected by the displacement sensor when the rolling element is detected by the displacement sensor, accurate rotation detection cannot be performed because of the revolution slip of the rolling element.

In addition, the techniques disclosed in Patent Documents 3 and 4 have the following problems.
-Since ultrasonic waves are repeatedly reflected and propagated in a complicated manner, it affects other ultrasonic sensors installed at other positions, and it is difficult to accurately detect the load.
-Since it is necessary to install an ultrasonic sensor so that an ultrasonic wave is emitted toward the contact surface between the rolling element and the rolling surface, it is difficult to position the ultrasonic sensor.
-The ultrasonic sensor is a dedicated sensor for load detection. If rotation detection is to be performed in addition to load detection, it is necessary to provide a separate rotation sensor.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sensor-equipped wheel bearing that is easy to mount a sensor and can accurately detect a load and rotation acting on the bearing only by mounting a single type of sensor.

The sensor-equipped wheel bearing according to the present invention includes an outer member in which a double row rolling surface is formed on the inner periphery, an inner member in which a rolling surface opposite to each of the rolling surfaces is formed on the outer periphery, In a wheel bearing comprising a double row rolling element interposed between both facing rolling surfaces and rotatably supporting the wheel with respect to the vehicle body, the rotating side member of the outer member and the inner member The rotation side member is provided with a gear-shaped pulsar ring in which a plurality of teeth are arranged in the circumferential direction, and a sensor for detecting the pulsar ring is provided on the fixed side member of the outer member and the inner member. Rotation speed detection means for detecting the rotation speed from the period of the output signal, and load detection means for detecting the load acting on the wheel bearing from the magnitude of the amplitude of the output signal of the sensor or the phase difference between the input signal and the output signal Is provided.
According to this configuration, the rotational speed detecting means for detecting the rotational speed from the period of the output signal of the sensor for detecting pulsar ring, and the wheel output from the magnitude of the amplitude of the output signal of the sensor or the phase difference between the input signal and the output signal. Since load detection means for detecting the load acting on the bearing is provided, the rotation of the wheel and the load acting on the wheel bearing can be accurately detected with a compact configuration consisting of only one type of sensor unit consisting of a pulsar ring and a sensor. Therefore, the sensor unit can be easily mounted on the wheel bearing.

  In the present invention, the sensor may be an ultrasonic sensor. In the case of an ultrasonic sensor, the degree of freedom in design is high because a certain distance may be provided between the transmission unit and the detection surface and between the detection surface and the reception unit. The ultrasonic sensor is also resistant to vibration. Furthermore, since ultrasonic waves have good directivity, the magnitude of the echo detected by the receiver and the reflection time (the phase difference between the input signal and the output signal changes as the reflection time changes) change even with a slight relative displacement. Easy and sensitive measurement results can be obtained. Furthermore, according to the configuration of the present invention, since ultrasonic waves propagate in the air, even if a plurality of sensors are installed, they hardly affect each other. Therefore, a plurality of sensors are installed to improve detection accuracy. It is possible to improve.

  In the present invention, two or more sensors may be provided, and at least two of the sensors may be arranged so as to have a phase difference of 90 ° in a circulation phase in which the adjacent unevenness of the pulsar ring is one cycle. . Thereby, the rotation direction can be detected.

  In the present invention, an origin detection part may be provided at one place in the circumferential direction of the pulsar ring, and an origin detection sensor for detecting the origin of the rotation position of the rotation side member by detecting the origin detection part may be provided. good. In this configuration, the rotation synchronization component of the amplitude of the output signal of the sensor that detects pulsarring can be stored and canceled as an offset fluctuation, so that a minute fluctuation in amplitude can be detected with high accuracy. Load detection is possible.

  In this invention, the fixed member may be an outer member, and the pulsar ring may be provided on the outer periphery of the inner member.

In the present invention, the rotation side member may be an inner member, the inner member may have a wheel mounting flange, and the pulsar ring may be provided on a side surface of the flange.
Since the wheel mounting flange is inclined by the applied load, the load can be detected with high sensitivity. Further, the pulsar ring and the sensor can be arranged using the gap between the flange for mounting the wheel of the inner member and the outer member, and a compact configuration can be achieved.

In the present invention, the sensors are provided at four locations in the circumferential direction of the stationary member, and the rotational speed detecting means detects the rotational speed from an output signal of at least one of the four sensors. The load detection means may detect the load from output signals of the four sensors.
In this configuration, loads in various directions can be estimated from the output signals of the four sensors.

In this invention, a pair of seals are provided to cover the outboard side end and the inboard side end of the bearing space between the fixed side member and the rotation side member, respectively, and the seal on the outboard side and the rolling element row on the seal side are provided. An outboard-side pulsar ring and an outboard-side sensor for detecting this pulsar ring are arranged between the inboard-side seal and this seal-side rolling element row, and the in-board-side pulsar ring and An inboard side sensor for detecting this pulsar ring is arranged, and the rotational speed detecting means detects a rotational speed from an output signal of at least one of the outboard side sensor and the inboard side sensor, The load detecting means detects the load from output signals of both the outboard side and inboard side sensors. It may be of.
In the case of this configuration, two sets of pulsar rings and sensors are provided at two locations on the outboard side and the inboard side that are separated in the axial direction, so that the load acting on the wheel bearing can be detected in more detail. For example, the load in the vehicle width direction can be detected from the difference between the outputs of the sensors on the outboard side and the inboard side. Further, since the pulsar ring and the sensor are arranged between the seal and the rolling element row, a sensor or the like can be installed in a compact manner by utilizing the space in the bearing, and the sensor and the pulsar ring can be waterproofed and rusted by the seal.

  The sensor-equipped wheel bearing according to the present invention includes an outer member in which a double row rolling surface is formed on the inner periphery, an inner member in which a rolling surface opposite to each of the rolling surfaces is formed on the outer periphery, In a wheel bearing comprising a double row rolling element interposed between both facing rolling surfaces and rotatably supporting the wheel with respect to the vehicle body, the rotating side member of the outer member and the inner member The rotation side member is provided with a gear-shaped pulsar ring in which a plurality of teeth are arranged in the circumferential direction, and a sensor for detecting the pulsar ring is provided on the fixed side member of the outer member and the inner member. Rotation speed detection means for detecting the rotation speed from the period of the output signal, and load detection means for detecting the load acting on the wheel bearing from the magnitude of the amplitude of the output signal of the sensor or the phase difference between the input signal and the output signal The sensor can be mounted easily. In, simply by mounting one type of sensor, and a rotation load applied to the bearing can be accurately detected.

  An embodiment of the present invention will be described with reference to FIGS. This embodiment is a third generation inner ring rotating type and is applied to a wheel bearing for driving wheel support. In this specification, the side closer to the outer side in the vehicle width direction of the vehicle when attached to the vehicle is referred to as the outboard side, and the side closer to the center of the vehicle is referred to as the inboard side.

  As shown in the sectional view of FIG. 1, the bearing for this sensor-equipped wheel bearing includes an outer member 1 in which a double row rolling surface 3 is formed on the inner periphery, and rolling facing each of these rolling surfaces 3. The inner member 2 formed with the surface 4 and the double row rolling elements 5 interposed between the outer member 1 and the rolling surfaces 3 and 4 of the inner member 2 are constituted. This wheel bearing is a double-row angular ball bearing type, and the rolling elements 5 are made of balls and are held by a cage 6 for each row. The rolling surfaces 3 and 4 are arc-shaped in cross section, and each rolling surface 3 and 4 is formed so that the contact angle is outward. Both ends of the bearing space between the outer member 1 and the inner member 2 are sealed by a pair of seals 7 and 8, respectively.

The outer member 1 is a fixed side member, and has a flange 1a attached to the knuckle in the suspension device (not shown) of the vehicle body on the outer periphery, and the whole is an integral part. The flange 1a is provided with vehicle body mounting holes 14 at a plurality of locations in the circumferential direction.
The inner member 2 is a rotating side member, and includes a hub wheel 9 having a hub flange 9a for wheel mounting, and an inner ring 10 fitted to the outer periphery of the end portion on the inboard side of the shaft portion 9b of the hub wheel 9. And become. The hub wheel 9 and the inner ring 10 are formed with the rolling surfaces 4 of the respective rows. An inner ring fitting surface 12 having a small diameter with a step is provided on the outer periphery of the inboard side end of the hub wheel 9, and the inner ring 10 is fitted to the inner ring fitting surface 12. A through hole 11 is provided at the center of the hub wheel 9. The hub flange 9a is provided with press-fitting holes 15 for hub bolts (not shown) at a plurality of locations in the circumferential direction. In the vicinity of the base portion of the hub flange 9a of the hub wheel 9, a cylindrical pilot portion 13 for guiding a wheel and a brake component (not shown) protrudes toward the outboard side.
FIG. 2 shows a front view of the wheel bearing as viewed from the inboard side. FIG. 1 is a cross-sectional view taken along the line I-O-I in FIG.

As shown in the cross-sectional view of FIG. 3A, the inner member 2 is positioned at an intermediate position in the axial direction between the rolling surfaces 4 and 4 of the two rows on the outer peripheral surface of the inner member 2 that is the rotation side member. A gear-shaped pulsar ring 16 in which a plurality of teeth 16a are arranged at an equal pitch in the circumferential direction is provided.
In addition, a pair of sensors 18 </ b> A and 18 </ b> B that form a sensor unit 30 with the pulsar ring 16 are provided on the inner peripheral surface of the outer member 1 that is a fixed member. The pair of sensors 18 </ b> A and 18 </ b> B serve as a detection unit that detects the pulsar ring 16, and the inner periphery of the outer member 1 is interposed via a ring-shaped sensor housing 19 so as to face the pulsar ring 16 in the radial direction. It is provided on the surface. These sensors 18A and 18B are composed of ultrasonic sensors having a transmitter 28 and a receiver 29 as shown in FIG. 3B, which is an enlarged view of a part of FIG. The reflected ultrasonic waves are reflected by the concavo-convex surface of the teeth 16a on the outer periphery of the pulsar ring 16 which is a reflection surface, and the reception unit 29 receives echoes of the reflected ultrasonic waves. Here, the pair of sensors 18 </ b> A and 18 </ b> B are provided separately above and below the outer member 1. The pair of sensors 18A and 18B are arranged so as to have a phase difference of 90 °, for example, in a circular phase having one period as a period from the adjacent peak 16aa to the valley 16ab of the teeth 16a of the pulsar ring 16. Note that the phase difference is omitted in the drawing of FIG.

  4A and 4B show waveform diagrams of detection signals output from the receiving portions 29 of the sensors 18A and 18B as the inner member 2 rotates, and FIG. 4C shows the sensor 18B. The arrangement of the teeth 16a of the pulsar ring 16 corresponding to the output waveform diagram is shown. Here, as the output signal of the receiving unit 29, the magnitude of an ultrasonic echo received by the receiving unit 29 is shown. That is, when the receiving unit 29 receives an echo reflected from the peak 16aa of the tooth 16a of the pulsar ring 16 by the ultrasonic wave emitted from the transmitting unit 28, the echo travel path is short and the echo received by the receiving unit 29 is large. However, when the receiving unit 29 receives the echo reflected by the valley 16ab of the tooth 16a of the pulsar ring 16, the echo travel path is long and the echo received by the receiving unit 29 is small. This echo change is output from the receiving unit 29 as an alternating waveform detection signal as shown in FIGS. Here, the magnitude of the echo reflected by the peak 16aa of the tooth 16a of the pulsar ring 16 received by the receiving unit 29 is used as the amplitude. Between the output signals of both sensors 18A and 18B shown in the figure, a phase difference of 90 ° is generated corresponding to the phase difference provided in the installation of both sensors 18A and 18B. That is, the output signals of both sensors 18A and 18B are AB phase signals.

  In addition, the magnitude of an echo reflected from the reflecting surface of the pulsar ring 16 by the ultrasonic wave emitted from the transmission unit 28 of the sensors 18A and 18B is detected by the reception unit 29 of the sensors 18A and 18B, and the period and size of the echoes. Although the case where the rotational speed and the load are detected from the fluctuations in the above is shown, the rotational speed and the load may be obtained by detecting the reflection time of the echo on the reflecting surface of the pulsar ring 16 (not shown). That is, when the ultrasonic waves emitted from the transmitters 28 of the sensors 18A and 18B are reflected by the peaks 16aa of the teeth 16a of the pulsar ring 16, the echo reflection time is shortened but reflected by the valleys 16ab of the teeth 16a of the pulsar rings 16. When doing so, the echo reflection time becomes longer. Therefore, if the reception unit 29 outputs the echo reflection time as a detection signal, the output waveform is an alternating waveform (of the teeth 16a of the pulsar ring 16) opposite to that in FIGS. 4 (A) and 4 (B). It is possible to detect the load from the fluctuation value of the amplitude of the waveform, and to detect the rotation speed from the period of the waveform, the minimum value at the peak portion 16aa and the maximum value at the valley portion 16ab of the teeth 16a of the pulsar ring 16.

Both sensors 18A and 18B are connected to a rotational speed detecting means 20 and a load detecting means 21. The rotational speed detecting means 20 is a means for detecting the rotational speed of the pulsar ring 16, that is, the inner member 2, from the period of the output signals of the sensors 18A and 18B. For detecting the rotational speed, it is sufficient to use one of the output signals of both the sensors 18A and 18B, but the rotational direction is detected from the phase difference between the two output signals.
The load detection means 21 is a means for detecting a load acting on the wheel bearing from the magnitude of the amplitude of the output signals of the sensors 18A and 18B. The load detection means 21 is composed of an electronic circuit, a microcomputer, and the like, and has relationship setting means (not shown) that sets the relationship between the amplitude of the output signals of the sensors 18A and 18B and the load. A load detection signal is output by comparing the output signal of 18B with the relationship setting means. The load detection means 21 may be a means for detecting a load acting on the wheel bearing from a phase difference (not shown) between the input signals and output signals of the sensors 18A and 18B.

Specifically, the load detection process by the load detection means 21 is performed as follows, for example. The amplitudes A and B of the output signals of the sensors 18A and 18B that detect the echoes of the ultrasonic waves reflected by the pulsar ring 16 are fluctuations in the distance between the ultrasonic reflection surface of the pulsar ring 16 and the sensors 18A and 18B, that is, inner members. 2 greatly varies due to a variation in the gap between the outer peripheral surface 2 and the inner peripheral surface of the outer member 1. Therefore, the amplitudes of the output signals of the sensors 18A and 18B vary according to the magnitude of the load applied to the wheel bearing.
Therefore, here, the load detection means 21 detects the gap fluctuation from the amplitudes A and B of the output signals of the sensors 18A and 18B, for example.
Alternatively, the load detection means 21 uses the amplitudes of the output signals of the sensors 18A and 18B before the sensor-equipped wheel bearings are incorporated in the vehicle as a reference value, and the reference values of the amplitudes A and B of the output signals of the sensors 18A and 18B. Fluctuations ΔA and ΔB with respect to, and as the magnitude G of the gap variation,
G = | ΔA | + | ΔB |
By calculating, the load acting on the wheel bearing is detected.
Alternatively, the phase difference between the input signals and the output signals of the sensors 18A and 18B that detect the echoes of the ultrasonic waves reflected by the pulsar ring 16 is a variation in the distance between the ultrasonic reflection surface of the pulsar ring 16 and the sensors 18A and 18B. Due to the fluctuation of the reflection time due to the gap between the outer peripheral surface of the inner member 2 and the inner peripheral surface of the outer member 1, it varies greatly. Therefore, the phase difference between the input signals and output signals of the sensors 18A and 18B varies according to the magnitude of the load applied to the wheel bearing.
Therefore, here, the load detection means 21 detects gap fluctuation from the phase difference between the input signals and output signals of the sensors 18A and 18B, for example.

Thus, according to this sensor-equipped wheel bearing, the pulsar ring 16 provided on the inner member 2 which is the rotation side member of the bearing and the pulsar ring 16 provided on the outer member 1 which is the fixed side member of the bearing are detected. With the compact configuration of only one type of sensor unit 30 composed of the sensors 18A and 18B, the rotation of the wheel and the load acting on the wheel bearing can be accurately detected, and the sensor unit 30 to the wheel bearing is detected. Can be easily mounted.
Further, in this embodiment, since the sensor unit 30 is disposed between the two rolling elements 5 and 5 in the inner space of the wheel bearing, the antirust treatment of the sensor unit 30 is also unnecessary.

FIG. 5 shows a cross-sectional view of another arrangement example of the sensors 18A and 18B in the sensor wheel bearing according to the embodiment. In this example, the pair of sensors 18A and 18B are placed at a position above the inner peripheral surface of the outer member 1, and the period from the peak 16aa to the valley 16ab of the teeth 16a in the pulsar ring 16 is 90 cycles. They are separated by a phase difference of °.
Also in this case, the output signals of both the sensors 18A and 18B become AB phase signals, the rotation direction can be detected from the phase difference between the two output signals, and the rotation speed can be detected using the period of one of the output signals. it can. However, the amplitude fluctuation of the output signals of both sensors 18A and 18B or the phase difference fluctuation of the input signal and the output signal in this case are both between the outer peripheral surface of the inner member 2 and the inner peripheral surface of the outer member 1 at the upper position. Therefore, the load detection means 21 may detect the load from the output signal of one of the sensors.

FIG. 6 shows a cross-sectional view of still another example of arrangement of sensors in the sensor-equipped wheel bearing according to the embodiment. In this example, sensors 18A to 18D are arranged at four locations in the circumferential direction of the outer member 1 that is a fixed member. That is, in this example, in addition to the pair of sensors 18A and 18B arranged above and below, a pair of sensors 18C and 18D arranged on the left and right are added. In this case, for example, if the above-described phase difference is set between the pair of upper and lower sensors 18A and 18B in order to detect the rotation direction, the phase difference need not be considered between the pair of left and right sensors 18C and 18D. The rotational speed detection means 20 detects the rotational speed from the output signal of at least one of the four sensors 18A to 18D, and the load detection means 21 detects the load from the output signals of the four sensors 18A to 18D. Is supposed to be detected.
In this case, the amplitude fluctuation of the output signal of the pair of upper and lower sensors 18A, 18B or the phase difference fluctuation of the input signal and the output signal is caused by the outer peripheral surface of the inner member 2 and the inner peripheral surface of the external member 1 at the upper and lower positions. The variation in the amplitude of the output signal of the pair of left and right sensors 18C and 18D or the variation in the phase difference between the input signal and the output signal reflects the gap variation in the left and right positions. Loads in various directions can be estimated from the signal.

FIG. 7 shows a partial plan view of another configuration example of the magnetic encoder 16 in the sensor-equipped wheel bearing according to the embodiment. In the pulsar ring 16 of this configuration example, the origin detected part 22 is provided at one place in the circumferential direction. Here, only the peak portion 16aa of one tooth 16a in the pulsar ring 16 protrudes in the axial direction from the other portion, and the protruding portion is used as the origin detected portion 22. Note that the origin detected part 22 may be constituted by a crest 16aa of two or three teeth 16a.
In this case, as a sensor for detecting the pulsar ring 16, apart from the above-described sensors 18A and 18B having an axial length capable of detecting the entire circumference of the pulsar ring 16, only the origin detected portion 22 is detected and a rotation side member. An origin detection sensor 23 for detecting the origin of the rotational position of the inner member 2 is provided.

  Thus, the origin detected part 22 is provided at one place in the circumferential direction of the pulsar ring 16, and this origin detected part 22 is detected by the origin detection sensor 23 to rotate the inner member 2 that is the rotation side member. When the origin of the position is configured to be detected, the rotation synchronization component of the amplitude of the output signal of the sensors 18A and 18B or the phase difference between the input signal and the output signal can be stored as an offset change and canceled. Small fluctuations in amplitude can be detected, and highly accurate load detection is possible.

FIG. 8 shows another embodiment of the present invention. In this embodiment, in the sensor-equipped wheel bearing of FIG. 1, the uneven surface of the teeth 16 a is formed on one surface of the inner member 2, which is a rotation-side member, facing the inboard side of the hub flange 9 a for mounting the wheel of the hub wheel 9. Is provided so as to be concentric with the inner member 2, and an uneven surface of the teeth 16 a of the pulsar ring 16 is provided at an end of the outer member 1 which is a fixed side member. A pair of upper and lower sensors 18A and 18B are provided so as to face each other in the axial direction. That is, in the embodiment of FIG. 1, the pulsar ring 16 and the sensors 18A and 18B are opposed in the radial direction, whereas in this embodiment, they are opposed in the axial direction. Other configurations are the same as those in the embodiment of FIG.
In the case of this embodiment, the pulsar ring 16 and the sensors 18A and 18B can be installed even if there is no room for installing the pulsar ring 16 and the sensors 18A and 18B in the bearing space. Further, since the hub flange 9a for wheel mounting is inclined due to the load acting on the wheel, the load can be detected with high sensitivity by providing the pulsar ring 16 here.

9 and 10 show still another embodiment of the present invention. Similarly to the sensor-equipped wheel bearing of FIG. 8, this embodiment also has the pulsar ring 16 and the sensors 18A and 18B facing each other in the axial direction. Here, two sets of the pulsar ring 16 and the sensors 18A and 18B are used. The sensor units 30 </ b> A and 30 </ b> B are arranged between the row of the outboard side rolling elements 5 and the outboard side seal 7 in the bearing inner space between the outer member 1 and the inner member 2, and the inboard side rolling element 5. And are distributed between the inboard side seal 8 and the inboard side seal 8. FIG. 10 shows a cross-sectional view of the installation part of the sensor unit 30A (30B). Here, the pulsar ring 16 is formed by arranging a plurality of windows 24 penetrating in the axial direction at equal pitches in the circumferential direction. Therefore, when the ultrasonic wave emitted from the transmission unit 28 of the sensors 18A and 18B is reflected by a portion without the window 24, the reception unit 29 can detect an echo, but when the ultrasonic wave passes through the window 24, the reception unit 29 Cannot detect echo. Accordingly, the sensors 18A and 18B can output an alternating waveform signal that is not affected by noise or the like as a detection signal. The sensors 18A and 18B are held by a ring-shaped sensor housing 19 provided on the inner peripheral surface of the outer member 1, as in the embodiment of FIG.
In this case, the rotational speed detection means 20 detects the rotational speed from the output signals of the sensors 18A and 18B in at least one of the two sensor units 30A and 30B, and the load detection means 21 The load is detected from the output signals of all the sensors 18A and 18B of the sensor units 30A and 30B.
In this embodiment, the seals 7 and 8 in the figure may be omitted as a configuration in which the two sensor units 30A and 30B are also used as seals.

  In this embodiment, since the sensor units 30A and 30B are provided at two locations on the outboard side and the inboard side that are separated in the axial direction, the load acting on the wheel bearing can be detected in more detail.

It is sectional drawing of the wheel bearing with a sensor which concerns on one Embodiment of this invention. It is a front view of the outward member of the wheel bearing. (A) is sectional drawing of the sensor unit installation part in the bearing for the wheels, (B) is the elements on larger scale of (A). (A), (B) is an output waveform diagram of a sensor in the wheel bearing, and (C) is an array diagram of pulsar ring teeth corresponding to the output waveform of (B). It is sectional drawing which shows the other example of arrangement | positioning of a sensor. It is sectional drawing which shows the other example of arrangement | positioning of a sensor. It is a fragmentary top view which shows the other structural example of a pulsar ring. It is sectional drawing of the bearing for wheels with a sensor which concerns on other embodiment of this invention. It is sectional drawing of the bearing for wheels with a sensor which concerns on other embodiment of this invention. It is sectional drawing of the sensor unit installation part in the wheel bearing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Outer member 1a ... Car body mounting flange 2 ... Inner member 3, 4 ... Rolling surface 5 ... Rolling body 7, 8 ... Seal 16 ... Pulsar ring 16a ... Teeth 18A-18D ... Sensor 20 ... Rotational speed detection means 21 ... Load detection means 22 ... Origin detected part 23 ... Origin detection sensor

Claims (8)

An outer member in which a double row rolling surface is formed on the inner periphery, an inner member in which a rolling surface facing each of the rolling surfaces is formed on the outer periphery, and the both facing rolling surfaces are interposed In a wheel bearing comprising a double row rolling element, and rotatably supporting the wheel with respect to the vehicle body,
A rotation-side member of the outer member and the inner member is provided with a gear-shaped pulsar ring in which a plurality of teeth are arranged in a circumferential direction of the rotation-side member, and a fixed side of the outer member and the inner member The member is provided with a sensor for detecting the pulsar ring, a rotational speed detecting means for detecting the rotational speed from the period of the output signal of the sensor, and the magnitude of the amplitude of the output signal of the sensor or the phase difference between the input signal and the output signal A sensor-equipped wheel bearing comprising a load detecting means for detecting a load acting on the wheel bearing.   The sensor-equipped wheel bearing according to claim 1, wherein the sensor is an ultrasonic sensor.   2. The sensor according to claim 1, wherein two or more sensors are provided, and at least two of the sensors have a phase difference of 90 ° in a circular phase having one cycle of adjacent unevenness of the pulsar ring. A wheel bearing with sensor, characterized by being arranged.   The origin detection part is provided in one place in the circumferential direction of the pulsar ring according to any one of claims 1 to 3, and the origin detection part is detected to determine the origin of the rotation position of the rotation side member. Sensor-equipped wheel bearing with a sensor for detecting the origin.   5. The sensor-equipped wheel bearing according to claim 1, wherein the fixed side member is an outer member, and the pulsar ring is provided on an outer periphery of the inner member.   5. The sensor according to claim 1, wherein the rotation side member is an inner member, the inner member has a wheel mounting flange, and the pulsar ring is provided on a side surface of the flange. 6. Wheel bearing.   7. The sensor according to claim 1, wherein the sensors are provided at four locations in the circumferential direction of the fixed-side member, and the rotational speed detection means is at least one of the sensors at the four locations. A sensor-equipped wheel bearing in which a rotational speed is detected from an output signal of a sensor, and the load detecting means detects the load from output signals of the four sensors. 8. The pair of seals according to claim 1, wherein a pair of seals respectively covering an outboard side end and an inboard side end of the bearing space between the fixed side member and the rotation side member are provided, and the outboard side is provided. An outboard side pulsar ring and an outboard side sensor for detecting the pulsar ring are arranged between the seal of the seal and the rolling element row on the seal side, and the seal on the inboard side and the rolling element row on the seal side An inboard side pulsar ring and an inboard side sensor for detecting the pulsar ring are disposed between the at least one of the outboard side sensor and the inboard side sensor. The rotation speed is detected from the signal, and the load detecting means outputs both the outboard side sensor and the inboard side sensor. Sensor equipped wheel support bearing assembly which is intended to detect the load from the signal.

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