JP2007071628A - Wheel bearing with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing with a sensor capable of setting a sensor for load detection on a vehicle, capable of sensitively detecting the load on a wheel and the cost at the time of mass production is lowered. <P>SOLUTION: The bearing for wheel intervened with double raw rotation body 3 between the external member 1 and the internal member 2 is fixed with sensor unit 21. The sensor unit 21 is composed of the ring member 22 or sensor fixing member to be fixed on the internal surface of the external member 1 being the stationary member and a strain sensor 23 for measuring the strain of the member. The material of the ring member 22 is used titanium alloy, phosphor bronze or hardening steel being a highly durable material. If the internal material 2 is the stationary member the ring member 22 or the sensor fixing member is fixed on the internal side member 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sensor-equipped wheel bearing with a built-in load sensor for detecting a load applied to a bearing portion 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 carried out 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 attitude 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. Further, even when the load is uneven, the load applied to each wheel becomes uneven. For this reason, if the load applied to the wheel can be detected at any time, based on the detection result, the suspension and the like are controlled in advance, thereby controlling the posture 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 is such that 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 been proposed in which a strain gauge is attached to the outer ring of the wheel bearing to detect the strain (for example, Patent Document 1).
Special table 2003-530565 gazette

An outer ring of a wheel bearing has a rolling surface and is a component that requires strength, and is a bearing component that is produced through complicated processes such as plastic working, turning, heat treatment, and grinding. Therefore, when a strain gauge is attached to the outer ring as in Patent Document 1, there is a problem that productivity is poor and the cost for mass production is high. Also, it is difficult to detect the outer ring distortion with high sensitivity.
Therefore, an attempt was made to improve productivity and detection sensitivity by attaching a sensor unit equipped with a strain gauge to the peripheral surface of the outer ring. In that case, in order to further improve the detection sensitivity of the member for attaching the strain gauge to the outer ring in the sensor unit, what is the best material and what shape should be used.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to install a sensor for detecting a load in a compact manner in a vehicle, to detect a load applied to the wheel with high sensitivity, and to reduce the cost at the time of mass production. Is to provide.

  The sensor-equipped wheel bearing according to the first aspect of the present invention includes an outer member having a double-row rolling surface formed on the inner periphery, and a rolling surface facing the rolling surface of the outer member. In a wheel bearing comprising an inner member and a double row rolling element interposed between both rolling surfaces and rotatably supporting the wheel with respect to the vehicle body, the ring member includes the outer member and the inner member. Among them, the fixing member is attached to the peripheral surface, a strain sensor for detecting strain of the ring member is attached to the ring member, and the material of the ring member is titanium, phosphor bronze, or hardened steel.

  According to a second aspect of the present invention, there is provided the sensor-equipped wheel bearing according to the first aspect, wherein the ring member is attached to a peripheral surface of a fixed-side member of the outer member and the inner member. The cross-sectional shape has a contact ring portion and a non-contact ring portion that are in contact with and non-contact with the peripheral surface of the fixed side member, respectively. Of the non-contact ring portion, a portion far from the contact ring portion is another portion. The thickness of the ring member is a thicker portion, and a strain sensor that measures the axial strain of the ring member is provided between the contact ring portion and the thick portion of the ring member. .

  According to a third aspect of the present invention, there is provided the wheel bearing with sensor according to the first aspect, wherein the ring member is attached to a peripheral surface of a fixed side member of the outer member and the inner member. The cross-sectional shape has a contact ring portion and a non-contact ring portion that are in contact with and non-contact with the peripheral surface of the stationary member, and a flange portion is provided in a portion far from the contact ring portion of the non-contact ring portion. And a strain sensor for measuring the axial strain of the ring member is provided between the contact ring portion and the flange portion of the ring member.

  According to a fourth aspect of the present invention, there is provided the wheel bearing with sensor according to the first aspect, wherein the ring member is attached to a peripheral surface of a fixed side member of the outer member and the inner member. The cross-sectional shape is a shape having a pair of contact ring portions that are axially separated from each other and contact the fixed side member, and a non-contact ring portion that is connected between the contact ring portions and does not contact the fixed side member. The ring portion is thinner than the contact ring portion, and the non-contact ring portion is provided with a strain sensor for measuring the axial strain of the ring member.

  According to a fifth aspect of the present invention, there is provided the wheel bearing with sensor according to the first aspect, wherein the ring member is attached to a peripheral surface of a fixed side member of the outer member and the inner member. The cross-sectional shape is a shape having a pair of contact ring portions that are axially separated from each other and contact the fixed side member, and a non-contact ring portion that is connected between the contact ring portions and does not contact the fixed side member. The contact ring part of the contact ring part is thinner than the other contact ring part and the non-contact ring part, and the contact ring part with a reduced thickness is provided with a strain sensor that measures the bending strain of the ring member. It is.

  According to a sixth aspect of the present invention, the sensor-equipped wheel bearing includes an outer member having a double-row rolling surface formed on the inner periphery, and a rolling surface facing the rolling surface of the outer member. In a wheel bearing comprising an inner member and a double-row rolling element interposed between both rolling surfaces and rotatably supporting the wheel with respect to the vehicle body, the sensor mounting member and the strain attached to the sensor mounting member A sensor unit including a sensor is attached to a peripheral surface of a fixed side member of the outer member and the inner member, and the sensor mounting member has at least two contact fixing portions with respect to the fixed side member. In addition, at least one notch portion is provided between adjacent contact fixing portions, and the strain sensor is disposed in this notch portion, and the sensor mounting member is made of titanium, phosphor bronze, or hardened steel. It is characterized by.

  In the first to sixth inventions, for example, when the outer member is a stationary member and the inner member is a rotating member, the ring member or the sensor unit is attached to the outer member.

In the first to sixth inventions, when a load is applied to the rotation side member as the vehicle travels, the fixed side member is deformed via the rolling elements, and the deformation causes distortion of the ring member or the sensor mounting member. The strain sensor provided on the ring member or the sensor mounting member detects the strain of the ring member or the sensor mounting member. If the relationship between strain and load is obtained in advance through experiments and simulations, the load applied to the wheel can be detected from the output of the strain sensor. That is, the external force acting on the wheel bearing, the acting force between the tire and the road surface, or the preload amount of the wheel bearing can be estimated from the output of the strain sensor. Further, the detected load or the like can be used for vehicle control of the automobile.
In this sensor-equipped wheel bearing, a strain sensor is attached to a ring member or a sensor attachment member that is attached to a fixed member, so that a load sensor can be installed in a compact vehicle. Since both the ring member and the sensor attachment member are simple parts that can be attached to the fixed side member, attaching a strain sensor to the ring member and the sensor attachment member can provide excellent mass productivity and reduce costs.

  In particular, in the first to sixth inventions, the material of the ring member or sensor mounting member is titanium, phosphor bronze, or hardened steel, which is an anti-durable material, so that the allowable strain amount of the sensor ring is increased. Sensing sensitivity can be improved.

In the second invention, since the portion far from the contact ring portion of the non-contact ring portion is a thick portion thicker than the other portions, it is highly rigid and difficult to deform. Therefore, the distortion generated between the thick wall portion and the contact ring portion is obtained by transferring and expanding the radial distortion of the stationary member.
In the third aspect of the invention, since the flange portion is provided in a portion of the non-contact ring portion that is far from the contact ring portion, the rigidity of the flange portion is high and hardly deformed. Therefore, the distortion generated between the flange portion and the contact ring portion is a transfer and enlargement of the radial distortion of the stationary member.
Therefore, both the second and third inventions can detect the distortion of the stationary member with high sensitivity, and can improve the detection accuracy.

  Further, in the fourth invention, the ring member includes a pair of contact ring portions that are axially separated from each other and contact the fixed side member, and a non-contact ring portion that is connected between the contact ring portions and does not contact the fixed side member. The contact ring portion is thicker than the non-contact ring portion and has high rigidity and is difficult to deform, but the non-contact ring portion has low rigidity and is easily deformed. Therefore, although the axial distortion occurs in the non-contact ring portion, this distortion is a transfer and enlargement of the axial distortion of the stationary member. Therefore, the deformation sensor provided in the non-contact ring portion can detect the deformation of the outer member with high sensitivity, and the detection accuracy can be increased.

  Also in the fifth aspect, the ring member includes a pair of contact ring portions that are axially separated from each other and contact the fixed side member, and a non-contact ring portion that is connected between the contact ring portions and does not contact the fixed side member. Although it has a shape, one of the contact ring parts is thinner than the other contact ring part and non-contact ring part. In this case, the contact ring portion having a reduced thickness is deformed in accordance with the deformation of the stationary member, but the other contact ring portion and the non-contact ring portion are highly rigid and difficult to deform. Therefore, a bending strain is generated in the contact ring portion having a reduced wall thickness, and this strain is an enlargement of the axial strain on the peripheral surface of the outer member. Therefore, the deformation of the outer member can be detected with high sensitivity by the strain sensor provided in the contact ring portion having a reduced thickness, and the detection accuracy can be increased.

  In the sixth invention, the sensor mounting member has at least two contact fixing portions with respect to the fixed side member, and has at least one notch portion between adjacent contact fixing portions. Since the strain sensor is arranged in the notch, the strain sensor placement location of the sensor mounting member causes greater strain than the fixed side member due to its rigidity reduction, and the strain of the fixed side member is detected with high sensitivity. Can do.

The sensor-equipped wheel bearing according to the present invention includes an outer member having a double-row rolling surface formed on the inner periphery, an inner member having a rolling surface facing the rolling surface of the outer member, A double-row rolling element interposed between both rolling surfaces, and a wheel bearing for rotatably supporting the wheel with respect to the vehicle body, wherein the ring member or the sensor mounting member is connected to the outer member and the inner member. A load sensor can be installed on the vehicle in a compact manner because it is mounted on the peripheral surface of the fixed member and a strain sensor for measuring the strain of the ring member or sensor mounting member is mounted on the ring member or sensor mounting member. . Since both the ring member and the sensor mounting member are simple parts that can be mounted on the fixed side member, by attaching a sensor for measuring distortion to the ring member and the sensor mounting member, the ring member and the sensor mounting member can be excellent in mass productivity, and the cost can be reduced.
Moreover, since the material of the ring member or the sensor mounting member is titanium, phosphor bronze, or hardened steel, which is an anti-durable material, the allowable strain amount of the sensor ring can be increased and the sensing sensitivity can be improved.
Furthermore, in the second to sixth inventions, the shape of the ring member or the sensor mounting member is a shape capable of amplifying and transmitting the strain of the fixed side member to the strain sensor mounting location on the ring member or the sensor mounting member. Therefore, the distortion of the fixed side member can be detected with high sensitivity.

A first 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.
This sensor-equipped wheel bearing includes an outer member 1 having a double row rolling surface 3 formed on the inner periphery, an inner member 2 having a rolling surface 4 opposed to each of the rolling surfaces 3, and these It is comprised by the double row rolling element 5 interposed between the rolling surfaces 3 and 4 of the outer member 1 and the inner member 2. 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 sealing means 7 and 8, respectively.

The outer member 1 is a fixed side member, and has a flange 1a attached to a knuckle in a suspension device (not shown) of a 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.

  A sensor unit 21 is provided on the inner periphery of the outer member 1 on the outboard side end. The axial position of the sensor unit 21 is between the sealing means 7 and the rolling surface 3. The sensor unit 21 includes a ring member 22 and a plurality of strain sensors 23 that are attached to the ring member 22 and measure the strain of the ring member 22. The strain sensors 23 are equally distributed at a plurality of locations in the circumferential direction of the ring member 22. In this example, the strain sensors 23 are provided at four locations corresponding to the upper and lower sides and the left and right sides of the wheel bearing. In this example, the cross-sectional shape of the ring member 22 is a rectangle.

  The ring member 22 is press-fitted and fixed to the inner peripheral portion of the outer member 1. In some cases, after press-fitting, it may be fixed with a bolt, an adhesive or the like. The ring member 22 preferably does not undergo plastic deformation during the press-fitting and does not undergo plastic deformation at the maximum expected external force acting on the wheel bearing or the acting force between the tire and the road surface. In addition, it is preferable that the allowable strain amount is large. In order to satisfy these matters, the material of the ring member 22 is any one of titanium, phosphor bronze, and hardened steel, which are materials having a high yield strength.

  The inboard side sealing means 8 includes a seal 8a made of an elastic body such as rubber with a core attached to the inner peripheral surface of the outer member 1, and the seal 8a attached to the outer peripheral surface of the inner ring 10. The slinger 8b is in contact with the slinger 8b. The slinger 8b is provided with a magnetic encoder 16 for rotation detection, which is composed of a multipolar magnet having magnetic poles alternately in the circumferential direction. A magnetic sensor (not shown) is attached to the outer member 1 so as to face the magnetic encoder 16.

  As shown in FIG. 4, load detection is performed by detecting the load or the like by processing the output of the strain sensor 23 by the external force calculation means 31, the road surface force calculation means 32, the bearing preload amount calculation means 33, and the abnormality determination means 34. The system is configured. These means 31 to 34 may be provided in an electronic circuit device (not shown) such as a circuit board attached to the outer member 1 or the like of the wheel bearing, or may be an electric control unit of an automobile. (ECU) may be provided.

The operation of the sensor-equipped wheel bearing with the above configuration will be described. When a load is applied to the hub wheel 9, the outer member 1 is deformed via the rolling elements 5, and the deformation is transmitted to the ring member 22 attached to the inner periphery of the outer member 1, and the ring member 22 is deformed. To do. The strain of the ring member 22 is measured by the strain sensor 23. Since the material of the ring member 22 is titanium, phosphor bronze, or hardened steel, which is an anti-durable material, it is possible to increase the allowable strain amount of the sensor ring and improve the sensing sensitivity.
Since the strain changes depending on the direction and magnitude of the load, if the relationship between the strain and the load is obtained in advance through experiments and simulations, the external force acting on the wheel bearing or the acting force between the tire and the road surface is calculated. be able to. The external force calculating means 31 and the road surface acting force calculating means 32 each act on the wheel bearing by the output of the strain sensor 23 based on the relationship between the strain and the load obtained and set in advance through experiments and simulations. Calculate external force and acting force between tire and road surface

The abnormality determining unit 34 outputs an abnormality signal to the outside when it is determined that the external force acting on the wheel bearing calculated in this way or the acting force between the tire and the road surface exceeds a set allowable value. . This abnormal signal can be used for vehicle control of an automobile.
If the external force calculating means 31 and the road surface acting force calculating means 32 output the external force acting on the wheel bearing in real time or the acting force between the tire and the road surface, finer vehicle control becomes possible.

  Further, a preload is applied to the wheel bearing by the inner ring 10, and the ring member 22 is also deformed by the preload. For this reason, if the relationship between strain and preload is obtained in advance through experiments and simulations, the preload state of the wheel bearing can be known. The bearing preload amount calculation means 33 outputs the bearing preload amount by the output of the strain sensor 23 based on the relationship between the strain and the preload obtained and set in advance through experiments and simulations as described above. Further, by using the preload amount output from the bearing preload amount calculation means 33, it becomes easy to adjust the preload when the wheel bearing is assembled.

5 to 7 show a second embodiment. Although this embodiment is different from the first embodiment in the shape of the ring member 22 constituting the sensor unit 21, the other components are the same as those in the first embodiment, and thus the same reference numerals are given to common portions. The description is omitted. The material of the ring member 22 is any of titanium, phosphor bronze, and hardened steel.
As shown in FIG. 7, the cross-sectional shape of the ring member 22 of this embodiment has a contact ring portion 22a and a non-contact ring portion 22b that are in contact and non-contact with the inner peripheral surface of the outer member 1, respectively. In the non-contact ring portion 22b, a portion far from the contact ring portion 22a is a thick portion 22c that is thicker than other portions.
On the outer peripheral surface of the non-contact ring portion 22b between the contact ring portion 22a and the thick portion 22c (the bottom of the concave groove shape portion between the contact ring portion 22a and the thick portion 22c), A strain sensor 23 for measuring axial strain is attached.

Also in this embodiment, when a load is applied to the hub wheel 9 as described above, the outer member 1 is deformed via the rolling elements 5, and the deformation is a ring attached to the inner periphery of the outer member 1. It is transmitted to the member 22 and the ring member 22 is deformed. The strain of the ring member 22 is measured by the strain sensor 23. In the sensor unit 21 of this embodiment, the non-contact part 22b of the part far from the contact ring part 22a of the ring member 22 is a thick part 22c that is thicker than other parts. Is difficult to deform. Therefore, the distortion generated between the thick wall portion 22c and the contact ring portion 22a is obtained by transferring and expanding the radial distortion of the outer member 1. Thereby, the deformation of the outer member 1 can be detected with high sensitivity by the strain sensor 23, and the strain measurement accuracy is increased.
Also in this embodiment, the output of the strain sensor 23 can be processed in the same manner as described above by the load detection system shown in FIG.

8 to 10 show a third embodiment. This embodiment is also different from the first and second embodiments in the shape of the ring member 22 constituting the sensor unit 21, but the other configurations are the same as those in the first and second embodiments. The same reference numerals are given and description thereof is omitted. The material of the ring member 22 is any of titanium, phosphor bronze, and hardened steel.
As shown in FIG. 10, the cross-sectional shape of the ring member 22 of this embodiment has a contact ring portion 22a and a non-contact ring portion 22b that are in contact and non-contact with the inner peripheral surface of the outer member 1, respectively. The point is the same as that of the first embodiment, but differs in that an inward flange portion 22d is provided in a portion far from the contact ring portion 22a in the non-contact ring portion 22b. In this case, the shaft of the ring member 22 is arranged on the outer peripheral surface of the non-contact ring portion 22b between the contact ring portion 22a and the flange portion 22d (the outer peripheral surface of the cylindrical portion between the contact ring portion 22a and the thick portion 22c). A strain sensor 23 for measuring the strain in the direction is attached.

Also in this embodiment, when a load is applied to the hub wheel 9, the outer member 1 is deformed via the rolling elements 5, and the deformation is applied to the ring member 22 attached to the inner periphery of the outer member 1. The ring member 22 is deformed. In the sensor unit 21 of this embodiment, since the inward flange portion 22d is provided in a portion of the non-contact ring portion 22b far from the contact ring portion 22a, the rigidity of the flange portion 22d is high and hardly deformed. Therefore, the distortion generated between the flange portion 22d and the contact ring portion 22a is a transfer and enlargement of the radial distortion of the outer member 1, and high-precision distortion measurement is expected as described above.
Also in this embodiment, the output of the strain sensor 23 can be processed in the same manner as described above by the load detection system shown in FIG.

11 to 13 show a fourth embodiment. This embodiment also has the same configuration as that of the first to third embodiments except for the ring member 22 constituting the sensor unit 21, and the same reference numerals are given to common portions and the description thereof is omitted. The material of the ring member 22 is any of titanium, phosphor bronze, and hardened steel.
As shown in FIG. 13, the cross-sectional shape of the ring member 22 of this embodiment is such that the contact ring portions 22aA and 22aB and the non-contact ring portion 22b are in contact and non-contact with the inner peripheral surface of the outer member 1, respectively. The non-contact ring portion 22b constitutes a bottom wall portion of the groove shape, and the contact ring portions 22aA and 22aB constitute side wall portions on both sides of the groove shape. The contact ring portions 22aA and 22aB on both sides are thicker than the non-contact ring portion 22b. The thickness mentioned here is the thickness in the radial direction for the non-contact ring portion 22b, and the thickness in the axial direction for the contact ring portions 22aA and 22aB.
A strain sensor 23 for measuring the axial strain of the ring member 22 is attached to the outer peripheral surface of the non-contact ring portion 22b, that is, the inner bottom surface of the ring member 22.

Also in this embodiment, when a load is applied to the hub wheel 9, the outer member 1 is deformed via the rolling elements 5, and the deformation is applied to the ring member 22 attached to the inner periphery of the outer member 1. The ring member 22 is deformed. The strain of the ring member 22 is measured by the strain sensor 23. In this case, the non-contact ring portion 22b is deformed according to the deformation of the outer member 1 mainly in the axial direction. On the other hand, since the contact ring portions 22aA and 22aB are thicker than the non-contact ring portion 22b, these portions are highly rigid and difficult to deform. Therefore, although the axial distortion occurs in the non-contact ring portion 22b, this distortion is a transfer and enlargement of the axial distortion of the inner periphery of the outer member 1, thereby measuring the distortion by the sensor 23. Increases accuracy.
Also in this embodiment, the output of the strain sensor 23 can be processed in the same manner as described above by the load detection system shown in FIG.

14 to 16 show a fifth embodiment. This embodiment also has the same configuration as that of the first to third embodiments except for the ring member 22 constituting the sensor unit 21, and the same reference numerals are given to common portions and the description thereof is omitted. The material of the ring member 22 is any of titanium, phosphor bronze, and hardened steel.
As shown in FIG. 16, the cross-sectional shape of the ring member 22 of this embodiment is such that the contact ring portions 22aC and 22aD and the non-contact ring portion 22b are in contact and non-contact with the inner peripheral surface of the outer member 1, respectively. It is the same as that of 4th Embodiment in having a groove shape. However, in the ring member 22 of this embodiment, among the contact ring portions 22aC and 22aD on both sides, the thickness of one contact ring portion 22aC is thicker than that of the other contact ring portion 22aD, and the thickness of the non-contact ring portion 22b. The thickness is made even thicker than these.
A strain sensor 23 for measuring the strain in the bending direction of the ring member 22 is affixed to the inner surface of the thinner contact ring portion 22aD, that is, the surface facing the contact ring portion 22aC. .

Also in this embodiment, when a load is applied to the hub wheel 9, the outer member 1 is deformed via the rolling elements 5, and the deformation is transmitted to the ring member 22 attached to the inner periphery of the outer member 1. The ring member 22 is deformed. In the sensor unit 21 of this embodiment, the contact ring portion 22aD to which the strain sensor 23 is attached is deformed mainly according to the axial deformation of the outer member 1, but the one contact ring portion 22aC and the non-contact ring Since the thickness of the portion 22b is increased, the portion 22b is highly rigid and hardly deformed, and bending strain is generated in the thinner contact ring portion 22aD. This distortion is obtained by transferring and expanding the axial distortion of the inner periphery of the outer member 1. Thereby, similarly to the fourth embodiment, highly accurate strain measurement is expected.
Also in this embodiment, the output of the strain sensor 23 can be processed in the same manner as described above by the load detection system shown in FIG.

17 to 19 show a sixth embodiment. This embodiment is different from the first to fifth embodiments in the configuration of the sensor unit 21, and the sensor unit 21 includes a sensor attachment member 24 attached to a part of the outer member 1 in the circumferential direction, and the sensor attachment A strain sensor 23 is attached to the member 24 and measures the strain of the sensor mounting member 22. Other than that, the configuration is the same as that of the first to fifth embodiments, and the same reference numerals are given to common portions, and the description thereof is omitted. The sensor mounting member 24 is made of titanium, phosphor bronze, or hardened steel.
As shown in FIG. 19, the sensor mounting member 24 has a substantially arc shape elongated in the circumferential direction along the inner peripheral surface of the outer member 1, and contact fixing portions 24a projecting to the outer peripheral side of the arc at both ends thereof. 224 is formed. In addition, a notch 24c that opens to the outer peripheral side of the arc is formed at the center of the sensor mounting member 24, and the strain sensor 24 is attached to the inner peripheral surface of the arc located on the back of the notch 24c. Yes. The cross-sectional shape of the sensor mounting member 24 is, for example, a rectangular shape, but can be various other shapes.

  The sensor unit 21 is fixed to the inner periphery of the outer member 1 by the contact fixing portions 24 a and 24 b of the sensor mounting member 24 so that the longitudinal direction of the sensor mounting member 24 faces the circumferential direction of the outer member 1. The contact fixing portions 24a and 24b are fixed to the outer member 1 by fixing with bolts or bonding with an adhesive. At locations other than the contact fixing portions 24 a and 24 b of the sensor mounting member 22, a gap is generated between the sensor mounting member 22 and the inner peripheral surface of the outer member 1. The first contact fixing portion 24a, which is one of the contact fixing portions 24a and 24b, is the outer member 1 at a circumferential location where the outer member 1 is most greatly deformed in the radial direction by a load acting on the outer member 1. Fixed to. The second contact fixing portion 24b is fixed at a location where there is less deformation in the radial direction than the fixed location.

In the case of this embodiment, when a load is applied to the hub wheel 9, the outer member 1 is deformed via the rolling elements 5, and the deformation is applied to the sensor mounting member 24 mounted on the inner periphery of the outer member 1. The sensor mounting member 24 is deformed. The strain of the sensor mounting member 24 is measured by the strain sensor 23. At this time, the sensor mounting member 24 is deformed in accordance with the radial deformation of the fixing portion of the sensor mounting member 24 in the outer member 1, but the sensor mounting member 24 has an arc shape compared to the outer member 1 and has a notch portion. Since 24c is provided and the rigidity is reduced at the position of the notch 24c, a strain larger than the strain of the outer member 1 appears at the strain sensor mounting portion of the sensor mounting member 24. For this reason, even a slight distortion of the outer member 1 can be accurately detected by the distortion sensor 23.
Also in this embodiment, the output of the strain sensor 23 can be processed in the same manner as described above by the load detection system shown in FIG.

In each of the above embodiments, the sensor unit 21 is provided on the inner periphery of the outer member 1, but the sensor unit 21 may be provided on the outer periphery of the outer member 1.
Moreover, although each said embodiment demonstrated about the case where an outer member is a stationary member, this invention can be applied also to the wheel bearing in which an inner member is a stationary member, in that case, The sensor unit 21 is provided on a peripheral surface that is an outer periphery or an inner periphery of the inner member.
Moreover, although each said embodiment demonstrated about the case where it applied to the bearing for 3rd generation type wheels, this invention is for 1st or 2nd generation type wheels from which a bearing part and a hub become mutually independent components. A bearing or a fourth generation type wheel bearing in which a part of the inner member is constituted by an outer ring of a constant velocity joint can also be applied. Further, the wheel bearing can be applied to a wheel bearing for a driven wheel, and can also be applied to a tapered roller type wheel bearing of each generation type.

It is sectional drawing of the bearing for wheels with a sensor concerning 1st Embodiment of this invention. It is a front view which shows the outward member and sensor unit of the wheel bearing with a sensor. It is a front view of the sensor unit. It is a block diagram which shows the conceptual structure of a load detection system. It is sectional drawing of the bearing for wheels with a sensor concerning 2nd Embodiment of this invention. It is a fragmentary sectional front view which shows the outward member and sensor unit of the wheel bearing with a sensor. (A) is a cross-sectional view of the sensor unit, and (b) is an enlarged view of the main part thereof. It is sectional drawing of the bearing for wheels with a sensor concerning 3rd Embodiment of this invention. It is a fragmentary sectional front view which shows the outward member and sensor unit of the wheel bearing with a sensor. (A) is a cross-sectional view of the sensor unit, and (b) is an enlarged view of the main part thereof. It is sectional drawing of the wheel bearing with a sensor concerning 4th Embodiment of this invention. It is a fragmentary sectional front view which shows the outward member and sensor unit of the wheel bearing with a sensor. (A) is a cross-sectional view of the sensor unit, and (b) is an enlarged view of the main part thereof. It is sectional drawing of the wheel bearing with a sensor concerning 5th Embodiment of this invention. It is a fragmentary sectional front view which shows the outward member and sensor unit of the wheel bearing with a sensor. (A) is a cross-sectional view of the sensor unit, and (b) is an enlarged view of the main part thereof. It is sectional drawing of the wheel bearing with a sensor concerning 6th Embodiment of this invention. It is a front view which shows the outward member and sensor unit of the wheel bearing with a sensor. (A) is a front view of the sensor unit, and (b) is a bottom view thereof.

Explanation of symbols

1 ... Outer member (fixed side member)
2 ... Inward member (rotary member)
3, 4 ... rolling surface 5 ... rolling elements 7, 8 ... sealing means 21 ... sensor unit 22 ... ring mounting members 22a, 22aA, 22aB, 22aC, 22aD ... contact ring portion 22b ... non-contact ring portion 23 ... strain sensor 24 ... Sensor mounting members 24a, 24b ... Contact fixing parts

Claims (7)

An outer member in which a double row rolling surface is formed on the inner periphery, an inner member having a rolling surface opposite to the rolling surface of the outer member, and a double row interposed between both rolling surfaces In a wheel bearing for supporting a wheel rotatably with respect to the vehicle body,
A ring member is attached to the peripheral surface of the fixed member of the outer member and the inner member, a strain sensor for detecting the strain of the ring member is attached to the ring member, and the material of the ring member is titanium or phosphorus. A wheel bearing with sensor, characterized by being made of bronze or hardened steel. An outer member in which a double row rolling surface is formed on the inner periphery, an inner member having a rolling surface opposite to the rolling surface of the outer member, and a double row interposed between both rolling surfaces In a wheel bearing for supporting a wheel rotatably with respect to the vehicle body,
A ring member is attached to the peripheral surface of the fixed side member of the outer member and the inner member, and the cross-sectional shape of the ring member is a contact that is in contact with or not in contact with the peripheral surface of the fixed side member. A ring portion and a non-contact ring portion, and a portion of the non-contact ring portion that is far from the contact ring portion is a thicker portion thicker than other portions, and the contact ring portion in the ring member A sensor-equipped wheel bearing, wherein a strain sensor for measuring the axial strain of the ring member is provided between the ring member and the thick part, and the material of the ring member is titanium, phosphor bronze, or hardened steel . An outer member in which a double row rolling surface is formed on the inner periphery, an inner member having a rolling surface opposite to the rolling surface of the outer member, and a double row interposed between both rolling surfaces In a wheel bearing for supporting a wheel rotatably with respect to the vehicle body,
A ring member is attached to the peripheral surface of the fixed side member of the outer member and the inner member, and the cross-sectional shape of the ring member is a contact that is in contact with or not in contact with the peripheral surface of the fixed side member. A ring portion and a non-contact ring portion are provided, and a flange portion is provided in a portion of the non-contact ring portion far from the contact ring portion, and the ring member is provided between the contact ring portion and the flange portion in the ring member. A sensor-equipped wheel bearing, comprising a strain sensor for measuring the axial strain of the ring member, wherein the ring member is made of titanium, phosphor bronze, or hardened steel. An outer member in which a double row rolling surface is formed on the inner periphery, an inner member having a rolling surface opposite to the rolling surface of the outer member, and a double row interposed between both rolling surfaces In a wheel bearing for supporting a wheel rotatably with respect to the vehicle body,
A ring member is attached to the peripheral surface of the fixed member of the outer member and the inner member, and the cross-sectional shape of the ring member is a pair of contact ring portions that are axially separated from each other and contact the fixed member And a shape having a non-contact ring portion that is connected between these contact ring portions and does not contact the fixed side member, the non-contact ring portion is thinner than the contact ring portion, and the non-contact ring portion, A sensor-equipped wheel bearing, comprising a strain sensor for measuring axial strain of a ring member, wherein the ring member is made of titanium, phosphor bronze, or hardened steel. An outer member in which a double row rolling surface is formed on the inner periphery, an inner member having a rolling surface opposite to the rolling surface of the outer member, and a double row interposed between both rolling surfaces In a wheel bearing for supporting a wheel rotatably with respect to the vehicle body,
A ring member is attached to the peripheral surface of the fixed member of the outer member and the inner member, and the cross-sectional shape of the ring member is a pair of contact ring portions that are axially separated from each other and contact the fixed member And a non-contact ring portion that is connected between the contact ring portions and does not contact the fixed side member, and one of the contact ring portions is thinner than the other contact ring portion and the non-contact ring portion. A wheel with a sensor, characterized in that a strain sensor for measuring the bending strain of the ring member is provided on the contact ring portion having a reduced wall thickness, and the ring member is made of titanium, phosphor bronze, or hardened steel. Bearings. An outer member in which a double row rolling surface is formed on the inner periphery, an inner member having a rolling surface opposite to the rolling surface of the outer member, and a double row interposed between both rolling surfaces In a wheel bearing for supporting a wheel rotatably with respect to the vehicle body,
A sensor unit comprising a sensor mounting member and a strain sensor mounted on the sensor mounting member is mounted on a peripheral surface of a fixed side member of the outer member and the inner member, and the sensor mounting member is mounted on the fixed side member. On the other hand, it has at least two contact fixing portions, and has at least one notch portion between adjacent contact fixing portions, and the strain sensor is arranged in this notch portion, and the sensor mounting member A wheel bearing with sensor, characterized in that the material is titanium, phosphor bronze or hardened steel.   The sensor-equipped wheel bearing according to any one of claims 1 to 6, wherein the stationary member is an outer member.

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