JP2008081089A - Bearing device for wheel with sensor containing in-wheel type motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a wheel with a sensor containing an in-wheel type motor capable of installing a sensor for detecting a load on a vehicle in a compact and highly productive manner and of sensitively detecting a load applied to a wheel. <P>SOLUTION: The output shaft 24 of an electric motor B is coaxially coupled to the hub 2 of the wheel of the vehicle on the same axis through a reduction gear C or directly. There are provided rolling-type bearings A for supporting the hub 2, which are applied to the bearing device for a wheel mounted on the suspension system of the vehicle through the housing 22 of the electric motor B or the housing 33b of the reduction gear C. The housing 22 of the electric motor B or the housing 33b of the reduction gear C is equipped with a distortion sensor 53 for detecting distortion of the housing. Further, there is provided a computing device 55 for detecting force in at least one direction among forces in three axial directions, which are a vertical direction, a lateral direction orthogonal to the vertical direction each other and a longitudinal direction, at the grounding point of the wheel mounted on the hub 2 and a road surface based on the output of the distortion sensor 53. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an in-wheel motor-equipped wheel bearing device in which a hub bearing, a speed reducer, and an electric motor are combined, and more particularly to a device provided with a sensor that detects a load applied to the hub bearing.

As a wheel bearing device for a vehicle such as an electric vehicle, an in-wheel type motor-integrated wheel bearing device in which a hub bearing, a speed reducer, and an electric motor are combined has attracted attention (for example, Patent Documents 1 and 2). When this in-wheel motor-equipped wheel bearing device is used as a driving wheel of an electric vehicle, each driving wheel can be individually driven to rotate, so that a large-scale power transmission mechanism such as a propeller shaft and a differential is not required. Can be made lighter and more compact.
JP 2005-7914 A JP-A-5-332401 (FIGS. 1-3) Special table 2003-530565 gazette

  When putting in-wheel motor-equipped wheel bearing devices into practical use, it is of course essential to measure the rotational speed of each wheel for traveling speed control, etc. It is also conceivable to measure the load acting on each wheel during vehicle travel and to control the vehicle attitude from the measurement result. 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.

  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.

In addition, in general wheel bearings used in engine-driven automobiles, in order to measure the load acting on the wheels, a strain gauge is attached to the outer ring of the bearing to detect distortion. (For example, Patent Document 3).
A general wheel bearing is fixed to a vehicle body via a suspension device attached to the outer ring of the bearing. On the other hand, the in-wheel motor built-in wheel bearing device is fixed to the vehicle body via a suspension device attached to the housing of the speed reducer or the housing of the electric motor. For this reason, in the in-wheel type motor-equipped wheel bearing device, as in the case of a general wheel bearing, if the strain gauge is attached to the outer ring of the hub bearing, the electric control unit and the strain gauge provided on the vehicle body The length of the portion of the wiring connecting the bearings on the bearing device side becomes long, and it takes time and effort to fix the portion of the wiring on the bearing device side, and the productivity is poor.

  An object of the present invention is to provide a wheel bearing device with a sensor with a built-in in-wheel type motor that can install a load detection sensor compactly and with high productivity in a vehicle and can detect a load applied to the wheel with high sensitivity.

  The in-wheel motor-equipped sensor-equipped wheel bearing device according to the present invention is a rolling type in which an output shaft of an electric motor and a vehicle wheel hub are connected coaxially via a speed reducer or directly and support the hub. In a wheel bearing device attached to a vehicle suspension through the housing of the electric motor or the housing of the speed reducer, the bearing is mounted on the housing of the electric motor or the housing of the speed reducer. A strain sensor for detecting the strain of the housing is attached, and the forces in the vertical direction, the left and right direction, and the front and rear direction that are orthogonal to each other at the contact point between the wheel attached to the hub and the road surface are determined from the output of the strain sensor. An arithmetic means for detecting a force in at least one of the directions is provided.

  When an external force acts on the contact point between the wheel and the road surface as the vehicle travels, a load is applied to the bearing, and each part of the bearing is deformed. This deformation is transmitted to the reduction gear housing and the electric motor housing. The strain due to the deformation of the housing is detected by a strain sensor attached to the housing of the electric motor or the housing of the reduction gear. Since the degree of distortion varies depending on the magnitude of the external force, the external force acting on the contact point between the wheel and the road surface can be detected from the output of the strain sensor if the relationship between the distortion and the external force is obtained in advance through experiments and simulations. The calculation means calculates the external force acting on the contact point between the wheel and the road surface by the output of the strain sensor based on the relationship between the external force and the strain obtained and set in advance through experiments and simulations. The external force acting on the contact point between the wheel and the road surface detected at that time is at least one of the forces in the three axial directions in the vertical direction, the left-right direction, and the front-rear direction orthogonal to each other at the contact point between the wheel and the road surface. It is the force of direction. This detected external force can be used for attitude control of the vehicle.

  Since the strain sensor is attached to the housing of the electric motor or the reducer, the length of the bearing side of the wiring connecting the electrical control unit and the strain sensor on the vehicle body can be shortened, making the strain sensor compact. And it can be installed with good productivity. For example, when a suspension is attached to the housing of the electric motor, a strain sensor is attached to the housing of the electric motor, and when a suspension is attached to the housing of the reduction gear, the strain sensor is attached to the housing of the reduction gear. When the is attached, the length of the portion of the wiring on the bearing device side can be further shortened.

In this invention, the bearing comprises 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 the rolling surfaces, and a flange formed on the outer periphery of the outer member and coupled to the electric motor housing or the speed reducer housing. In this case, the strain sensor may be attached to the outer periphery of the housing of the electric motor or the housing of the speed reducer that is coupled to the flange of the outer member, and in the vicinity of the coupling location with the flange.
When a strain sensor is attached to the outer periphery of the housing, the strain sensor can be easily installed. Further, if the strain sensor mounting position is in the vicinity of the location where the housing is connected to the flange, the deformation of the outer member is transmitted to the strain sensor mounting location without being attenuated so much, so that the strain can be detected with high sensitivity.

The strain sensor is attached to the housing of the electric motor or the reducer through a sensor attachment member, and the sensor attachment member is attached at two locations whose both ends are separated in the circumferential direction of the housing. It is good as a thing.
The degree of deformation of the housing of the electric motor or the housing of the speed reducer due to an external force acting on the contact point between the wheel and the road surface varies depending on each part in the circumferential direction. When both ends of the sensor mounting member are mounted at two locations that are separated in the circumferential direction of the housing, the sensor mounting member is deformed greatly on the side mounted at a location where deformation is large, with the side mounted at a location where deformation is small serving as a fulcrum. To do. For this reason, the strain sensor mounting portion of the sensor mounting member generates a larger strain, and the strain of the housing can be detected with high sensitivity by the strain sensor.

  The in-wheel motor-equipped sensor-equipped wheel bearing device according to the present invention is a rolling type in which an output shaft of an electric motor and a vehicle wheel hub are connected coaxially via a speed reducer or directly and support the hub. In a wheel bearing device attached to a vehicle suspension through the housing of the electric motor or the housing of the speed reducer, the bearing is mounted on the housing of the electric motor or the housing of the speed reducer. A strain sensor for detecting the strain of the housing is attached, and the forces in the vertical direction, the left and right direction, and the front and rear direction that are orthogonal to each other at the contact point between the wheel attached to the hub and the road surface are determined from the output of the strain sensor. Since the calculation means for detecting the force in at least one of the directions is provided, a sensor for detecting the load is installed on the vehicle in a compact and highly productive manner. Can be, the load applied to the wheel can be sensitively detected.

  A first embodiment of the present invention will be described with reference to FIGS. This in-wheel type sensor-equipped wheel bearing device with a built-in in-wheel motor includes a hub bearing A that rotatably supports a wheel hub, an electric motor B as a rotational drive source, and a speed reduction of the rotation of the electric motor B. It is a combination of a reduction gear C that transmits. In this embodiment, the hub bearing A is a third generation type inner ring rotating type in which the inner member of the bearing forms part of the hub. 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 FIG. 1, the hub bearing A includes an outer member 1 in which double-row rolling surfaces 3 are formed on the inner periphery, and an inner member in which rolling surfaces 4 that face the respective rolling surfaces 3 are formed. 2 and double row rolling elements 5 interposed between the rolling surfaces 3 and 4 of the outer member 1 and the inner member 2. The hub bearing A is a double-row angular ball bearing type, and the rolling elements 5 are formed 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. The end of the bearing space between the outer member 1 and the inner member 2 is sealed with a seal member 7.

  The outer member 1 is a stationary raceway, and has a flange 1a attached to the housing 33b on the outboard side of the speed reducer C on the outer periphery, and the whole is an integral part. The flange 1a is provided with bolt insertion holes 14 at a plurality of locations in the circumferential direction. Further, the housing 33b is provided with a bolt screw hole 44 whose inner periphery is threaded at a position corresponding to the bolt insertion hole 14. The outer member 1 is attached to the housing 33b by screwing the attachment bolt 15 inserted into the bolt insertion hole 14 into the bolt screw hole 44.

  The inner member 2 serves as a rotating raceway, and the outboard side member 9 having a hub flange 9a for attaching a wheel and the outer side of the outboard side member 9 are fitted on the outer side of the outboard side member and caulked. And the inboard side material 10 integrated with the outboard side material 9. The rolling surface 4 of each said row | line | column is formed in these outboard side materials 9 and inboard side materials 10. FIG. A through hole 11 is provided at the center of the inboard side member 10. The hub flange 9a is provided with insertion holes 17 for hub bolts 16 at a plurality of locations in the circumferential direction. In the vicinity of the root portion of the hub flange 9a of the outboard side member 9, a cylindrical pilot portion 13 for guiding a wheel and a braking component (not shown) protrudes toward the outboard side. A cap 18 that closes the outboard side end of the through hole 11 is attached to the inner periphery of the pilot portion 13.

  The electric motor B is an axial gap type in which an axial gap is provided between a stator 23 fixed to a cylindrical housing 22 and a rotor 25 attached to an output shaft 24. The output shaft 24 is cantilevered by two bearings 26 on the cylindrical portion of the housing 33a on the inboard side of the speed reducer C. The inboard side end of the gap between the output shaft 24 and the housing 33 a is sealed with a seal member 27. A cap 28 is attached to the opening on the inboard side of the housing 22.

  As shown in FIGS. 1 and 3, the speed reducer C is configured as a cycloid speed reducer. In other words, the speed reducer C has two curved plates 34a and 34b formed with wavy trochoidal curves having a gentle outer shape, mounted on the eccentric portions 32a and 32b of the input shaft 32 via bearings 35, respectively. A plurality of outer pins 36 passed to the housing 33b guide the eccentric movement of the curved plates 34a, 34b on the outer peripheral side, and a plurality of inner pins 38 attached to the inboard side member 10 of the inner member 2 The curved plates 34a and 34b are inserted into and engaged with a plurality of through holes 39 provided inside the curved plates 34a and 34b. The input shaft 32 is spline-coupled with the output shaft 24 of the electric motor B so as to rotate integrally. The input shaft 32 is supported at both ends by two bearings 40 on the housing 33a on the inboard side and the inner diameter surface of the inboard side member 10 of the inner member 2.

  When the output shaft 24 of the electric motor B rotates, the curved plates 34a and 34b attached to the input shaft 32 that rotates integrally with the output shaft 24 perform an eccentric motion. The eccentric motion of each of the curved plates 34a and 34b is transmitted as rotational motion to the inner member 2 which is a wheel hub by the engagement of the inner pin 38 and the through hole 39. The rotation of the inner member 2 is decelerated with respect to the rotation of the output shaft 24. For example, a reduction ratio of 1/10 or more can be obtained with a single-stage cycloid reducer.

  The two curved plates 34a and 34b are mounted on the eccentric portions 32a and 32b of the input shaft 32 so that the vibrations caused by the eccentric motion are canceled out from each other, and are mounted on both sides of the eccentric portions 32a and 32b. Is a counterweight that is eccentric in the direction opposite to the eccentric direction of the eccentric portions 32a and 32b so as to cancel the vibration caused by the inertial couple around the axis orthogonal to the rotation axis generated by the eccentric movement of the curved plates 34a and 34b. 41 is attached.

  As shown in FIG. 4, bearings 42 and 43 are mounted on the outer pins 36 and the inner pins 38, and the outer rings 42a and 43a of the bearings 42 and 43 are respectively connected to the outer circumferences of the curved plates 34a and 34b and the outer rings 42a and 34b. It comes into rolling contact with the inner periphery of the through hole 39. Therefore, the contact resistance between the outer pin 36 and the outer periphery of each curved plate 34a, 34b and the contact resistance between the inner pin 38 and the inner periphery of each through hole 39 are reduced, and the eccentric motion of each curved plate 34a, 34b is smooth. Can be transmitted to the inner member 2 as a rotational motion.

  This wheel bearing device is fixed to the vehicle body via a suspension device (not shown) such as a knuckle attached to the outer peripheral portion of the housing 33b of the reduction gear C or the housing 22 of the electric motor B.

  As shown in FIGS. 1 and 2, a strain sensor 53 for measuring the strain of the housing 33 b is attached to the outer periphery of the outboard side housing 33 b of the speed reducer C. In the case of this embodiment, the mounting position of the strain sensor 53 in the circumferential direction is a position directly above, that is, a position on the opposite road surface side. Also, the axial mounting position is set in the vicinity of the joint with the flange 1a. The strain sensor 53 is fixed to the housing 33b using, for example, an adhesive.

  The strain sensor 53 is connected to a calculation unit 55 and an abnormality determination unit 56 for processing the output of the strain sensor 53. These means 55 and 56 may be provided in an electronic circuit device (not shown) such as a circuit board attached to the wheel bearing device, or may be provided in an electric control unit (ECU) of an automobile. It may be.

  The operation of the in-wheel motor-equipped sensor-equipped wheel bearing device having the above-described configuration will be described. When the electric motor B is driven to rotate, the rotation of the output shaft 24 of the electric motor B is decelerated and transmitted to the inward member 2 that is a wheel hub via the speed reducer C, and the vehicle rotates to rotate the wheel. . When the vehicle travels, a force is applied to the wheel from the contact point between the wheel and the road surface. The force is a combination of forces in the three-axis directions of the vertical direction, the horizontal direction, and the front-rear direction orthogonal to each other.

  The hub bearing A is deformed by the external force. This deformation is transmitted from the outer member 1 of the hub bearing A to the outboard housing 33b of the reduction gear C. The distortion sensor 53 detects the distortion due to this deformation. Since the degree of distortion differs depending on the magnitude of the external force, if the relationship between the distortion and the external force is obtained in advance through experiments and simulations, the external force acting on the contact point between the wheel and the road surface can be detected from the output of the strain sensor 53. . The external force acting on the contact point between the wheel and the road surface detected at that time is at least one of the forces in the three axial directions in the vertical direction, the left-right direction, and the front-rear direction orthogonal to each other at the contact point between the wheel and the road surface. It is the force of direction.

  The calculating means 55 calculates the external force acting on the contact point between the wheel and the road surface from the output of the strain sensor 53 based on the relationship between the external force and the strain obtained and set in advance through experiments and simulations. Information on the detected external force can be used for attitude control of the vehicle. The abnormality determining means 56 outputs an abnormality signal to the outside when it is determined that the external force applied to the wheel and the ground contact point calculated by the calculating means 55 exceeds an allowable value. This abnormality signal can also be used for vehicle attitude control. Furthermore, if an external force acting on the contact point between the wheel and the road surface is output in real time, finer attitude control becomes possible.

  Since the strain sensor 53 is attached to the housing 33b of the speed reducer C, the distance between the suspension device and the strain sensor 53 is short. For this reason, the length of the bearing device side portion of the wiring connecting the electric control unit provided in the vehicle body and the strain sensor 53 can be shortened, and the strain sensor 53 can be installed compactly and with high productivity. Moreover, since the strain sensor 53 is attached to the outer periphery of the housing 33b, the strain sensor 53 can be easily installed.

  When the strain sensor 53 is attached in the vicinity of the joint portion of the housing 33b with the flange 1a as in this embodiment, the deformation of the outer member 1 is transmitted to the attachment portion of the strain sensor 53 without being attenuated so much. It can be detected with high sensitivity. When it is difficult to attach the strain sensor 53 to the above position due to physical circumstances or the like, as shown by a two-dot chain line in FIG. 1, other locations on the outer periphery of the housing 33 b of the speed reducer C and the electric motor B A strain sensor 53 may be attached to the outer periphery of the housing 22.

  5 and 6 show different attachment methods of the strain sensor 53. FIG. In this attachment method, the strain sensor 53 is attached to the sensor attachment member 52 to form the sensor unit 51, and the sensor unit 51 is attached to the outer periphery of the housing 33b of the reduction gear C or the housing 22 of the electric motor B. In the illustrated example, the sensor unit 51 is attached to the outer periphery of the axially central portion of the housing 33b of the speed reducer C.

  The sensor mounting member 52 has a substantially arc shape elongated in the circumferential direction along the outer periphery of the housing 33b, and contact fixing portions 52a and 52b projecting toward the inner peripheral side of the arc are formed at both ends thereof. In addition, a notch 52c that opens to the inner peripheral side of the arc is formed at the center of the sensor mounting member 52, and the strain sensor 53 is affixed to the outer peripheral side of the arc that is located at the back of the notch 52c. Yes. The cross-sectional shape of the sensor mounting member 52 is, for example, a rectangular shape, but may be various other shapes.

  The sensor unit 51 is fixed to the outer periphery of the housing 33b by the contact fixing portions 52a and 52b of the sensor mounting member 52 so that the longitudinal direction of the sensor mounting member 52 faces the circumferential direction of the housing 33b. The contact fixing portions 52a and 52b are fixed to the housing 33b by fixing with bolts or bonding with an adhesive. At locations other than the contact fixing portions 52a and 52b of the sensor mounting member 52, a gap is generated between the sensor mounting member 52 and the outer peripheral surface of the housing 33b. The first contact fixing portion 52a, which is one of the contact fixing portions 52a and 52b, is fixed to the housing 33b at a circumferential position where the housing 33b is most greatly deformed in the radial direction by a load acting on the housing 33b. The second contact fixing portion 52b is fixed at a location where there is less deformation in the radial direction than the fixed location.

  As described above, when the first contact fixing portion 52a is attached to a location where the first contact fixing portion 52a is greatly deformed in the radial direction as compared with other locations in the housing 33b, the sensor attachment member 52 is a second contact fixing portion with less deformation. 52b serves as a fulcrum, and the first contact fixing portion 52a is greatly deformed as the housing 33b is largely deformed. Therefore, the mounting location of the strain sensor 53 of the sensor mounting member 52 causes a greater strain, and the strain sensor 53 can detect the strain of the housing 33b with higher sensitivity.

  Of the contact fixing portions 52a and 52b, the second contact fixing portion 52b is different from the first contact fixing portion 52a in the direction of the radial distortion caused by the external force acting on the ground contact point between the wheel and the road surface. It is good also as a place where forward and backward differ. For example, it acts on the ground contact point between the tire and the road surface at a position above the right side position of the housing 33b (position 90 degrees above the road surface side position) and below the right side position (position near the road surface side). The direction of the radial deformation of the housing 33b with respect to the axial force is different in the forward and reverse directions. When the first contact fixing portion 52a is at a position directly above the housing 33b (opposite road surface side position), if the second contact fixing portion 52b is positioned at a position lower than the position directly lateral to the housing 33b, both contact fixing portions 52a, The direction of deformation of the housing 33b at 52b is different from the normal direction. As described above, when the second contact fixing portion 52b and the first contact fixing portion 52a are different from each other in the direction of the radial distortion of the housing 33b, the distortion on both sides is added. Thus, the deformation of the housing 33b is largely transmitted to the sensor mounting member 52, and an even greater strain can be detected to detect the strain of the housing 33b with higher sensitivity.

  FIG. 7 shows a second embodiment of the present invention. In this embodiment, the electric motor B is a radial gap type in which a radial gap is provided between a stator 103 fixed to the housing 102 and a rotor 105 attached to the output shaft 104. The output shaft 104 is splined to the input shaft 32 of the speed reducer C. Except for the electric motor B, the configuration is the same as that of the first embodiment. Also in the second embodiment, the strain sensor 53 is attached to the outer periphery of the housing 33b of the reduction gear C or the housing 102 of the electric motor B. As a result, the attitude of the vehicle can be controlled by measuring the force acting on the wheel at the contact point between the wheel and the road surface.

  FIG. 8 shows a third embodiment of the present invention. In this embodiment, the speed reducer C is a planetary speed reducer. The electric motor B is a radial gap type as in the second embodiment. In the planetary reduction gear C, a sun gear 113 is integrally provided on the outer periphery of the input shaft 112, and a plurality of planetary gears 115 meshing with the sun gear 113 and the inner teeth 114 provided on the inner periphery of the outboard housing 33b of the reduction gear. Is rotatably supported by an inner pin 118 attached to the inboard side member 10 of the inner member 2. Also with this planetary reduction gear, the rotation of the output shaft 104 of the electric motor B can be decelerated and transmitted to the inner member 2 that is a hub. However, the reduction ratio is not as great as that of the cycloid reducer. In the third embodiment, the strain sensor 53 is attached to the outer periphery of the housing 33b of the reduction gear C or the housing 102 of the electric motor B. As a result, the attitude of the vehicle can be controlled by measuring the force acting on the wheel at the contact point between the wheel and the road surface.

In each of the embodiments described above, the output of the electric motor B is decelerated by the reduction gear C and transmitted to the wheel hub. However, without providing the reduction gear C, the output shaft of the electric motor B and the wheel It is good also as a structure which connects with the hub 2 directly. In that case, the strain sensor 53 is attached to the housing 22 of the electric motor C.
In each of the above embodiments, the case where the hub bearing A is applied to a wheel bearing device of the third generation type has been described. However, in the present invention, the inner member of the hub bearing A and the wheel hub are independent of each other. The present invention can also be applied to a first or second generation type wheel bearing device. Further, the present invention can be applied to a wheel bearing device in which the hub bearing A is a tapered roller type of each generation type.

It is sectional drawing of the wheel bearing apparatus with a sensor with a built-in in-wheel type motor concerning 1st Embodiment of this invention. It is a front view of the outward member of the hub bearing of the bearing device for wheels, the housing of a reduction gear, and a distortion sensor. FIG. 3 is a sectional view taken along line III-III in FIG. 1. It is sectional drawing which expands and shows the principal part of FIG. It is a front view of the outer member of the hub bearing of the bearing device for wheels from which the attachment method of a strain sensor differs, the housing of a reduction gear, and a sensor unit. (A) is a top view of the sensor unit of the bearing device for wheels, (B) is the side view. It is sectional drawing of the wheel bearing apparatus with an in-wheel type motor built-in sensor concerning 2nd Embodiment of this invention. It is sectional drawing of the bearing apparatus for wheels with a sensor with a built-in in-wheel type motor concerning 3rd Embodiment of this invention.

Explanation of symbols

1 ... Outer member 2 ... Inner member (hub)
DESCRIPTION OF SYMBOLS 5 ... Rolling elements 22, 102 ... Electric motor housing 24, 104 ... Output shaft 33b ... Reduction gear housing 51 ... Sensor unit 52 ... Sensor mounting member 53 ... Strain sensor 55 ... Calculation means 56 ... Abnormality judgment means A ... Hub bearing B ... Electric motor C ... Reducer

Claims (4)

An output shaft of the electric motor and a wheel hub of the vehicle are connected coaxially via a reduction gear or directly, and a rolling type bearing is provided to support the hub, and the bearing is connected to the housing of the electric motor, or In the wheel bearing device attached to the vehicle suspension through the housing of the reduction gear,
A strain sensor for detecting the distortion of the housing is attached to the housing of the electric motor or the reducer, and from the output of the strain sensor, the upper and lower surfaces orthogonal to each other at the grounding point of the wheel attached to the hub and the road surface. An in-wheel motor-equipped sensor-equipped wheel bearing device, comprising: a calculating means for detecting a force in at least one of three directions of a direction, a left-right direction, and a front-rear direction.   In claim 1, the bearing is an outer member in which double-row rolling surfaces are formed on the inner periphery, and an inner member in which a rolling surface facing the rolling surface of the outer member is formed, An in-wheel type motor built-in sensor connected to the housing of the electric motor or the housing of the speed reducer with a flange formed on the outer periphery of the outer member. Wheel bearing device with attached wheels.   3. The in-wheel motor built-in device according to claim 2, wherein the strain sensor is attached to an outer periphery of the housing of the electric motor or the housing of the reduction gear that is coupled to the flange of the outer member and in the vicinity of the coupling portion with the flange. Bearing device for wheels with sensor.   4. The strain sensor according to claim 1, wherein the strain sensor is attached to a housing of the electric motor or a housing of a speed reducer via a sensor attachment member, and both ends of the sensor attachment member are located in the housing. An in-wheel motor-equipped sensor-equipped wheel bearing device that can be attached at two locations separated in the circumferential direction.

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