JP6724751B2 - Wheel with sensing device - Google Patents

Description

The present invention relates to a wheel with a sensing device that can be used to measure a load acting on a wheel.

In recent years, various vehicle control systems such as ABS (anti-lock brake system), TCS (traction control system), and VSC (vehicle stability control) have been developed in order to ensure driving stability and driving safety of automobiles. There is. Then, in order to control such a vehicle control system, it is required to accurately detect the conditions (for example, rotation speed, load, temperature, etc.) of the running wheels.

In view of such circumstances, Patent Literature 1 discloses a technique for determining a load (ground contact load or the like) acting on a wheel based on measuring the amount of deformation of the tire among the tires forming the wheel and the wheel. It is disclosed. According to such a technique, it is possible to obtain the load acting on the running wheel, and it is possible to use it for posture control of the automobile.
However, in the case of such a technique, there is a problem in that aged deterioration and a change in air pressure are likely to occur in the tire, and the accuracy of load measurement is likely to be deteriorated accordingly.

On the other hand, Patent Literature 2 discloses a technique for determining the load acting on the wheel based on the measurement of the deformation amount of the wheel among the tires forming the wheel and the wheel using a strain sensor. In the case of such a technique, aged deterioration is less likely to occur in the wheel (compared to tires), so that there is no problem that the accuracy of load measurement is likely to be deteriorated due to the aged deterioration.
However, in the case of such a technique, since the wheel has a very high rigidity (compared to the tire), the amount of deformation when a load is applied is small, and in the measurement by the strain sensor, the accuracy and sensitivity are mainly measured. There is a problem that it is difficult to secure sufficient reliability.

JP, 2011-93426, A JP, 2002-39744, A

In view of the circumstances as described above, the present invention has been devised to realize a structure in which it is easy to ensure the reliability of measurement of a load acting on a wheel.

A wheel with a sensing device of the present invention includes a wheel that constitutes a wheel and a sensing device.
Each of the wheels has a cylindrical rim portion on the outer diameter side on which a tire can be mounted, and a disc portion whose radial outer end portion is connected to the rim portion.
Further, the sensing device has a displacement extracting member and a sensor unit.
Of these displacement take-out members, one end in the radial direction is supported (cantilevered) on a part of the wheel in the one end side in the radial direction (including one end or a portion near the one end), and the other end in the radial direction is a free end. Has become.
Further, the sensor unit includes a sensor case, a detected body having a detected portion, and a detection body having a detection element whose output changes as the positional relationship with the detected portion changes.
In such a sensor unit, any one of the detecting body and the detected body is disposed inside the sensor case in a state in which relative displacement with the sensor case is blocked. There is.
Further, the other part of the detection body and the detection body, in a state in which relative displacement with the sensor case is enabled, the detection part and the detection element inside the sensor case. While facing each other, part of itself is located outside the sensor case.
Further, the sensor case is provided with respect to one of the radial other end portion of the wheel (including the other end portion or a portion near the other end) and the radial other end portion of the displacement extracting member. It is fixed.
Further, a portion of the other component located outside the sensor case is fixed to the other portion of the radial other end portion of the wheel and the radial other end portion of the displacement extracting member. Has been done.
As the detection body, a displacement sensor of various detection methods such as an eddy current type, an electrostatic capacitance type, a laser type, and a magnetic detection type can be adopted according to the property (type) of the detected body. ..

When the wheel with a sensing device of the present invention is implemented, for example, it is possible to adopt a configuration in which the detection body is the one component and the detection target is the other component. Further, in this case, the detection body has a plurality of planar coils each of which is the detection element, and one to a plurality of substrates (equal to or less than the number of planar coils) on which the plurality of planar coils are mounted. In addition, any one of the plurality of plane coils changes its output when the positional relationship with the detected portion changes at least in a predetermined direction. The remaining planar coil among them changes the output when the positional relationship with the detected part changes in a direction peculiar to itself, which is different from at least other planar coils. Can be adopted.

Further, when adopting such a configuration, for example, any one of the planar coils faces the detection target portion in the predetermined direction and has a positional relationship with the detection target portion. Even when changing in a direction different from the predetermined direction, the facing area of the detected portion in the predetermined direction does not change, the remaining planar coil is in the predetermined direction with respect to the detected portion. It is said that the facing area with respect to the detected portion in the predetermined direction changes as the positional relationship with the detected portion changes in a direction peculiar to itself while facing each other. Different configurations can be adopted.

When the wheel with a sensing device of the present invention is implemented, for example, the sensor unit is provided between the sensor case and the other component, and seals a gap that communicates the inside and the outside of the sensor case. A sensor seal can be added.

When the wheel with a sensing device of the present invention is implemented, for example, the sensing device has a plurality of the sensor units, and the plurality of sensor units are arranged so as to be separated from each other in the circumferential direction of the wheel. It is possible to adopt the structure which has.

According to the wheel with a sensing device of the present invention configured as described above, it is possible to easily ensure the reliability of measurement of the load acting on the wheel (tire and wheel).
That is, in the case of the present invention, for example, when a load is applied to the wheel, the wheel is elastically deformed by an amount corresponding to the load. As a result, the positional relationship between the detection target part of the detection target and the detection element of the detection target forming the sensor unit changes, and the output of the detection element of the detection target changes accordingly. Therefore, the load can be obtained by using the output of the detection element of this detection body. Particularly, in the case of the present invention, the radial one end of the displacement take-out member is supported by the radial one end side portion of the wheel, and the radial other end side of the wheel and the radial direction of the displacement take-out member are The sensor case (one part) is fixed to either part of the other end (free end), and the other part is also positioned outside the sensor case of the other part. The part to be fixed is fixed. Therefore, the amount of change in the positional relationship between the detected portion of the detected body and the detection element of the detected body, which occurs when the load acting on the wheel is changed, is the same as the radial direction one end side portion of the wheel. The amount of change in the positional relationship with the portion on the other end side in the direction also increases, and the amount of change in the output of the detection element of the detection body also increases. Further, the detected body and the detected body are arranged close to each other based on the existence of the displacement extracting member. Therefore, the output of the detection element of the detection body can be increased. Therefore, the reliability of the load measurement can be easily ensured.

The perspective view which looked at the wheel with a sensing device of the 1st example of an embodiment of the invention from the direction outside of an axis. Similarly, the perspective view seen from the axial inside. Similarly, the top view (a) seen from the axial direction outer side, and the AA sectional view (b) of (a). Similarly, the plan view seen from the inner side in the axial direction. The B section enlarged view of FIG. CC sectional drawing of FIG. The figure seen from the right side of FIG. The perspective view (a) seen from the axial inner side and the perspective view (b) seen from the axial outer side regarding the sensor unit which comprises the 1st example of embodiment of this invention. Similarly, the perspective view which saw a part and was seen from the axial direction outer side. Similarly, the top view (a) seen from the axial inside, and the DD sectional view (b) of (a). Similarly, a plan view (a) viewed from the inside in the axial direction with the sensor case omitted, and a view (b) viewed from below (a). FIG. 6 is a diagram showing theoretical values of output signals regarding axial displacements of a plurality of sensor units in a state where wheels are rotating while receiving a constant load. Sectional drawing which shows the wheel with a sensing device of the 1st example of embodiment of this invention in the state combined with the tire and the rolling bearing unit for wheel support. FIG. 3A is a plan view of the sensor unit constituting the second example of the embodiment of the present invention as seen from the inside in the axial direction with the sensor case omitted, and FIG. FIG. 6 is a perspective view of a sensor unit constituting a third example of an embodiment of the present invention, with a part cut away and viewed from the outside in the axial direction. Similarly, FIG. 16 is a plan view seen from above. Similarly, the side view seen from the front side of FIG. The same figure as FIG. 16 regarding the sensor unit which comprises the 4th example of embodiment of this invention. Similarly, the same figure as FIG.

[First Example of Embodiment]
A first example of the embodiment of the present invention will be described with reference to FIGS.
The wheel with a sensing device of this example includes a wheel 1 and a sensing device 2.
In this specification, unless otherwise specified, the term “outer” in the axial direction refers to the outer side in the width direction of the vehicle body when assembled in the vehicle. The left side, on the contrary, the right side in FIGS. 3B, 6 and 13, which is the center side in the width direction of the vehicle body, is referred to as “inside” in the axial direction.

The wheel 1 constitutes a wheel 4 (see FIG. 13) together with a rubber tire 3 and is made of an elastic metal such as an iron alloy or an aluminum alloy. In the case of this example, the wheel 1 has a one-piece structure in which the whole is integrally made by casting such as die casting. Such a wheel 1 has a cylindrical rim portion 5 on the outer diameter side on which the tire 3 can be mounted, and a disc portion 6 having a radially outer end portion coupled to the rim portion 5.

The disk portion 6 has an annular mounting portion 7 that constitutes an inner end portion in the radial direction and a plurality of spokes 8 and 8 that constitute an intermediate portion and an outer end portion in the radial direction.

Of these, the mounting portion 7 is a portion that is coupled and fixed to the hub 47 that constitutes the wheel supporting rolling bearing unit 45 as shown in FIG. 13, for example. The inner surface of the mounting portion 7 in the axial direction is a planar (annular surface) mounting surface 9 that is orthogonal to the central axis of the mounting portion 7. The mounting portion 7 has mounting holes 10 and 10 penetrating in the axial direction at a plurality of positions (five in the present example) at equal intervals in the circumferential direction. The axial inner ends of the mounting holes 10 and 10 are open to the radial middle portion of the mounting surface 9.

In addition, in the mounting surface 9, at a plurality of positions (in the present example, the same number as the mounting holes 10 and 10) at equal intervals in the circumferential direction, which are separated from the mounting holes 10 and 10. Are provided with inner diameter side holding recesses 11, 11 which are recessed in the axial direction, respectively, over the entire length in the radial direction. That is, the inner diameter side holding recesses 11 and 11 are provided so as to open in three directions, that is, the mounting surface 9 and both the inner and outer peripheral surfaces of the mounting portion 7. Further, in the case of this example, the mounting holes 10 and 10 and the inner diameter side holding recesses 11 and 11 are alternately arranged at equal pitches in the circumferential direction.

Further, a large-diameter step portion 12 having an inner diameter larger than that of a portion adjacent to the axially outer side is provided at the axially inner end portion of the inner peripheral surface of the mounting portion 7 over the entire circumference. ing. The large-diameter step portion 12 and the inner-diameter side holding concave portions 11 and 11 are overlapped in the radial direction, and the radial inner ends of the respective inner-diameter side holding concave portions 11 and 11 are formed in the large-diameter step portion 12. Each is open.

The spokes 8, 8 are radially arranged with being spaced apart from each other in the circumferential direction, and the radial inner end is the axial outer end of the outer peripheral surface of the mounting portion 7, and the radial outer end is the radial outer end. The inner peripheral surface of the rim portion 5 is integrally coupled to a portion of the inner peripheral surface near the outer end in the axial direction.

The sensing device 2 includes a displacement takeout member 13 and a plurality of sensor units 14, 14.

The displacement take-out member 13 is arranged radially inside the rim portion 5 and axially inside the disc portion 6, and has a radially outer end portion that is a radially outer end portion of the wheel 1. The rim portion 5 is supported in a cantilever manner, and the radially inner end portion is a free end. In the case of this example, such a displacement take-out member 13 is made integrally with the wheel 1 by the same kind of metal as that of the wheel 1, and a plurality of pieces (book In the case of the example, the pseudo spokes 15 and 15 of the same number as the spokes 8 and 8 and the annular ring-shaped connecting portion 16 that connects the radial inner ends of the pseudo spokes 15 and 15 to each other. Have.

The radial outer ends of the pseudo spokes 15 and 15 are integrally coupled to the axially outer end portions of the inner peripheral surface of the rim portion 5, respectively. In the case of this example, the connecting position of the radial outer ends of the pseudo spokes 15 and 15 with respect to the inner peripheral surface of the rim portion 5 is the same as the connecting position of the radial outer ends of the spokes 8 and 8. In addition, it is a position displaced inward in the axial direction and a position displaced in the circumferential direction. However, in the case of carrying out the present invention, the pseudo spokes 15 and 15 are arranged so as to overlap with the spokes 8 and 8 inward in the axial direction (when viewed from the outside in the axial direction, the spokes 8 and 15). , 8 can be concealed behind, that is, they can be superposed in the axial direction, in other words, can be arranged in the same phase in the circumferential direction).

On the other hand, the annular connecting portion 16 is arranged coaxially (concentrically) with the mounting portion 7 on the radially outer side of the axially inner end portion of the mounting portion 7. Further, in this state, the inner surface of the annular connecting portion 16 in the axial direction is arranged at a position slightly outward of the mounting surface 9 in the axial direction. Further, on the inner surface in the axial direction of the annular connecting portion 16, a plurality of locations (five in this example) aligned with the inner diameter side holding recesses 11, 11 in the circumferential direction are arranged in the axial direction. The outer diameter side holding recesses 17, 17 to be recessed are provided so as to open in two directions, respectively, an axial inner surface and an inner peripheral surface of the annular connecting portion 16.

The plurality of sensor units 14, 14 are arranged so as to bridge the wheel 1 and the displacement take-out member 13 between the inner diameter side holding recesses 11, 11 and the outer diameter side holding recesses 17, 17, respectively. In the mounted state, the wheels 1 are arranged at a plurality of locations spaced apart in the circumferential direction of the wheel 1. Each of these sensor units 14, 14 has a sensor case 18, a detection body 19, a detected body 20, and an O-ring 21 corresponding to the sensor seal described in the claims.

The sensor case 18 is made of, for example, a synthetic resin or a non-conductive metal material, and has a shallow rectangular container-shaped first case component 22 and an opening portion of the first case component 22 on the side opposite to the bottom plate portion. By combining with the second case part 23 having a rectangular plate shape to be closed, it is formed into a hollow, substantially rectangular parallelepiped shape.

As shown in FIGS. 2 to 7, in the state where the sensor unit 14 is attached to the wheel 1 and the displacement extracting member 13, the sensor case 18 has a thickness direction (α direction in FIGS. 8 to 10). In the axial direction of the wheel 1, the longitudinal direction (β direction in FIGS. 8 to 10) is the radial direction (radial direction) of the wheel 1, and the lateral direction (γ direction in FIGS. 8 to 10) is the circle of the wheel 1. Matched in the circumferential direction.

Such a sensor case 18 projects in the longitudinal direction from a hollow rectangular parallelepiped main body portion 24 and a longitudinal center portion of one longitudinal end surface (outer end surface in the radial direction of the wheel 1) of the main body portion 24. And the cylindrical portion 25 provided in the state of being. The inside and outside of the sensor case 18 are communicated with each other through the inside of the cylindrical portion 25 in the radial direction.

Further, the central axis of the cylindrical portion 25 is offset to one side in the thickness direction (outer side in the axial direction of the wheel 1) of the central portion of the main body portion 24 in the thickness direction. Then, a semi-cylindrical portion 26 continuous in the longitudinal direction from the cylindrical portion 25 bulges to one side in the thickness direction at the lateral center portion of the side plate portion on one side in the thickness direction which constitutes the main body portion 24. It is provided in the state.

Further, the central portion of the end plate portion on the other end side in the longitudinal direction (the inner end side in the radial direction of the wheel 1) that constitutes the main body portion 24 penetrates the central portion densely in the longitudinal direction. In the state, a cylindrical sleeve 27 is provided.

In addition, fixing flanges 28 and 28 are provided at the end portions of the both end surfaces of the main body portion 24 in the lateral direction opposite to each other in the longitudinal direction, respectively. The both fixing flanges 28, 28 are provided with through holes 29, 29, respectively.

The detection body 19 includes a rectangular substrate 30 and a first plane coil (first detection element) 31 mounted (printed) at two positions separated from each other in the longitudinal direction on one side surface in the thickness direction of the substrate 30. And a second plane coil (second detection element) 32 (see FIGS. 9 and 11). The first plane coil 31 and the second plane coil 32 are each connected to a circuit (not shown) mounted on one side surface in the thickness direction of the substrate 30.

Such a detection body 19 is arranged (held and fixed) inside the sensor case 18 in a state in which relative displacement with the sensor case 18 is blocked. Therefore, in the illustrated example, the substrate 30 is formed by the protrusions 33a and 33a provided on the inner surface of the first case component 22 and the protrusions 33b and 33b provided on the inner surface of the second case component 23. It is sandwiched. However, when carrying out the present invention, the method of holding and fixing the detection body 19 inside the sensor case 18 is not particularly limited, and for example, a fixing method using screws, fasteners or the like can be adopted. ..

One end of a wiring (harness) 34 for supplying power and transmitting a signal (illustrated only in FIG. 13, but not shown in other drawings) is electrically connected to the detection body 19. 34 is pulled out to the outside of the sensor case 18 (inward of the wheel 1 in the radial direction) in a state where the sleeve 34 is tightly inserted inside the radial direction of the sleeve 27.

The detected body 20 is made of a conductive material such as an iron alloy or a copper alloy, and is fixed to the rod portion 35 and one longitudinal end portion (outer end portion in the radial direction of the wheel 1) of the rod portion 35. And a fixing portion 36. The fixing portion 36 is provided with a pair of through holes 37, 37.

The rod portion 35 has a columnar portion 38 on one end side in the longitudinal direction and a semi-columnar portion 39 on the other end side in the longitudinal direction (inner end side in the radial direction of the wheel 1).

The outer diameter of the cylindrical portion 38 is smaller than the inner diameter of the cylindrical portion 25 of the sensor case 18. Further, a locking groove 40 is provided over the entire circumference at an intermediate portion in the longitudinal direction of the outer peripheral surface of the cylindrical portion 38. The O-ring 21 is locked in the locking groove 40.

One side surface in the radial direction of the semi-cylindrical portion 39 (an outer surface in the axial direction of the wheel 1) is a semi-cylindrical surface that is smoothly continuous with the outer peripheral surface of the semi-cylindrical portion 38. On the other hand, the other radial side surface of the semi-cylindrical portion 39 (the inner side surface in the axial direction of the wheel 1) serves as a flat detected portion 41 that is orthogonal to the thickness direction of the sensor case 18. ing.

In such a detected body 20, the rod portion 35 is inserted into the inside of the sensor case 18 through the inside of the cylindrical portion 25 in the radial direction in a state where the relative displacement with the sensor case 18 is enabled. ing.

In this state, the O-ring 21 is elastically compressed between the bottom surface of the locking groove 40 and the inner peripheral surface of the cylindrical portion 25. As a result, the O-ring 21 seals the insertion portion of the rod portion 35 with respect to the sensor case 18, and the detected body 20 is attached to the sensor case 18 in the longitudinal direction of the sensor case 18 (the wheel). 1 is elastically supported so as to be capable of relative displacement in a radial direction) and a thickness direction (axial direction of the wheel 1).

Further, in this state, the semi-cylindrical portion 39 of the rod portion 35 is arranged on the inner diameter side of the semi-cylindrical portion 26 of the sensor case 18, and the detected portion 41 has the first and second portions. The flat coils 31 and 32 are closely opposed to each other. More specifically, as shown in FIGS. 9 and 11, the other end portion in the longitudinal direction of the detected portion 41 is close to at least a part of the first planar coil 31 on one side in the longitudinal direction. Facing each other. Further, an intermediate portion in the longitudinal direction of the detected portion 41 closely faces and opposes the entire second planar coil 32.

In such a positional relationship, when the detected body 20 and the sensor case 18 (the detected body 19) are displaced relative to each other in the longitudinal direction of the sensor case 18, the detected portion 41 and the second plane surface. Although the facing area of the coil 32 does not change, the facing area of the detected part 41 and the first flat coil 31 changes, so that the output of the second flat coil 32 remains constant and the first flat coil 31 does not change. Only the output of changes.

On the other hand, when the detected body 20 and the sensor case 18 (the detected body 19) are relatively displaced in the thickness direction of the sensor case 18, the detected portion 41 and the first and second planar coils 31. , 32, the output distances of the first and second planar coils 31, 32 both change.

Further, in the case of this example, even if the detected body 20 and the sensor case 18 (the detected body 19) are relatively displaced in the lateral direction of the sensor case 18, the detected portion 41 and the detected portion 41 are The dimensions of each part are regulated so that the facing areas of the first and second planar coils 31 and 32 do not change (the outputs of the first and second planar coils 31 and 32 do not change).

That is, the first planar coil 31 has a longitudinal direction (β direction in FIGS. 8 to 10 and a radial direction that is a radial direction of the wheel 1) and a thickness direction (α direction in FIGS. 8 to 10 and an axis of the wheel 1). Function as a displacement sensor having a sensitivity in the axial direction), and the second planar coil 32 has a sensitivity in the thickness direction (the α direction in FIGS. 8 to 10 and the axial direction that is the axial direction of the wheel 1). It functions as a displacement sensor with a chisel.

When the relative displacements in the two directions (thickness direction, longitudinal direction) described above occur at the same time, the relative displacement amount in the thickness direction (axial direction of the wheel 1) between the detected body 20 and the detected body 19 is Similarly, the relative displacement amount in the longitudinal direction (radial direction of the wheel 1) is obtained by the output of the second plane coil 32, and the output of the first plane coil 31 is corrected using the output of the second plane coil 32. Required by doing.

In the case of this example, the second planar coil 32 corresponds to “any one planar coil of the plurality of planar coils” described in the claims, and the first planar coil 31 is Corresponds to the "remaining planar coil among the plurality of planar coils" described in the claims.

Each of the sensor units 14 and 14 as described above has a through hole 29 formed in the fixing flanges 28 and 28 of the sensor case 18 in a state where the sensor case 18 is arranged inside the inner diameter side holding recess 11. , 29 are inserted into screw holes provided in a state in which the screws 42, 42 inserted into the inner diameter side holding recesses 11, 11 are opened in the portions of the bottom surfaces of the inner diameter side holding recesses 11, 11 aligned with the through holes 29, 29, respectively. Further tightening. Thereby, the sensor case 18 (detector 19) is fixed to the mounting portion 7 of the wheel 1. Further, in the case of the present example, in this state, the entire sensor case 18 (and each of the screws 42, 42) is positioned axially outside the mounting surface 9 of the mounting portion 7.

Further, in each of the sensor units 14 and 14, with the fixing portion 36 of the detected body 20 arranged inside the outer diameter side holding concave portion 17, through holes 37 and 37 provided in the fixing portion 36, respectively. Screw the screws 43, 43 into the screw holes provided in the state of opening in the bottom surface of the outer diameter side holding concave portion 17 aligned with these through holes 37, 37, and further tighten. There is. Thereby, the detected body 20 is fixed to the annular connecting portion 16 of the displacement extracting member 13. Further, in the case of the present example, in this state, the entire fixing portion 36 (and each of the screws 43, 43) is positioned outside the axial inner surface of the annular connecting portion 16 in the axial direction. ..

Further, in the case of this example, in the free state in which no load is applied to the wheel 1, the first and second planar coils 31 and 32 of the detection body 19 and the detected portion 41 of the detection body 20 are The sensor units 14, 14 have the same positional relationship with each other.

The wheel with a sensing device of the present example having the above-described configuration is used for braking with the wheel 4 configured by mounting the tire 3 on the outer diameter side of the rim portion 5 as shown in FIG. 13, for example. Along with the brake rotor 44, which is a rotating member, a wheel supporting rolling bearing unit 45 rotatably supports a suspension device (not shown).

In the case of the illustrated example, the wheel supporting rolling bearing unit 45 is for a driven wheel that supports the wheel 4 as a driven wheel, and is provided on the inner diameter side of the outer ring 46, which is a stationary side race ring, on the rotating side raceway. A hub 47, which is a wheel, is rotatably supported via a plurality of balls 48, which are rolling elements.

The outer ring 46 is configured in a generally annular shape as a whole, and has outer row raceways 49a and 49b in multiple rows on the inner peripheral surface and a stationary side flange 50 on the outer peripheral surface.

The hub 47 is formed by combining a substantially annular hub body 51 and an inner ring 52, has double rows of inner ring raceways 53a and 53b on the outer peripheral surface, and the outer ring 46 on the inner diameter side of the outer ring 46. It is supported coaxially. Specifically, the inner ring raceway 53a of the axially outer row is directly formed at the axially intermediate portion of the outer peripheral surface of the hub body 51, and the axially inner row of the outer circumferential surface is also formed at the portion closer to the axially inner end. The inner ring 52 having the inner ring raceway 53b is externally fitted and fixed. Further, a rotation for supporting the wheel 4 and the brake rotor 44 is provided at a portion of the axially outer end portion of the hub body 51 that projects axially outwardly beyond the axially outer end opening of the outer ring 46. A side flange 54 is provided. Further, the rotation side flange 54 is provided with a mounting hole (screw hole or through hole) 55 penetrating in the axial direction.

Each of the balls 48, 48 is provided between the outer ring raceways 49a, 49b and the inner ring raceways 53a, 53b such that a plurality of balls for each row are held by a cage and are rollable. Has been. Further, in this state, a preload is applied to the balls 48 on both rows together with the contact angle of the back combination type.

Further, a seal ring 56 is installed between the axially outer end opening of the outer ring 46 and the outer peripheral surface of the hub body 51 in the axial direction so that the balls 48, 48 are installed in the axial direction of the space. The outer end opening is blocked. Further, a bottomed cylindrical cap (cover) 57 is fixed to the axially inner end of the outer ring 46 to close the axially inner end opening of the outer ring 46. In the case of this example, at least the bottom plate portion of the cap 57 is made of a non-magnetic material such as non-magnetic metal or synthetic resin.

When the wheel 4 and the brake rotor 44 are rotatably supported by the suspension device by the wheel supporting rolling bearing unit 45 as described above, the stationary side flange 50 of the outer ring 46 is fixed to the suspension device. The knuckle that constitutes the device is connected and fixed by a plurality of connecting members such as bolts.

Further, the wheel 4 and the brake rotor 44 are fixedly coupled to the rotary side flange 54 of the hub 47 (hub body 51). For this reason, specifically, the brake rotor 44 is provided in the center portion of the brake rotor 44 in the radial direction, and in the center portion of the wheel 1 in the radial direction (inside the mounting portion 7 in the radial direction). By sequentially inserting (inner-fitting) a positioning tubular portion 58, which is called a pilot portion, provided at the axially outer end portion of the hub body 51 into the wheel center hole, the wheel 1 and the brake rotor 44 are radial direction. The positioning of. Along with this, the axially inner surface of the radially inner half of the brake rotor 44 is brought into contact with the axially outer surface of the rotary side flange 54, and the axially outer surface of the radially inner half of the brake rotor 44 is brought into contact. The mounting surface 9 of the wheel 1 is brought into contact with. Then, in this state, the mounting holes 55 of the rotation-side flange 54, the mounting holes 59 of the brake rotor 44, and the mounting holes 10 of the mounting portion 7 of the wheel 1 which are arranged at positions axially aligned with each other. The wheel 1 (mounting portion 7) and the brake rotor 44 are coupled and fixed to the hub body 51 (rotation side flange 54) by using a plurality of coupling members such as bolts (not shown) that are inserted or screwed into To do.

Further, in the case of the present example, the wheel supporting rolling bearing unit 45 includes a power supply means (not shown), a signal communication means (not shown), and a rotation angle detection means (not shown). Particularly, in the case of this example, the power supply means, the signal communication means, and the rotation angle detection means are installed in the space radially inside the hub 47 and the internal space of the cap 57.

The power supply unit includes a generator, a battery, and a charger. The generator includes a stator that is directly or indirectly supported and fixed to the outer ring 46, or a rotor that is directly or indirectly supported and fixed to the hub 47. Based on the relative rotation between the stator and the rotor, the electric power supplied to the sensor units 14, 14 is generated. The battery stores the electric power generated by the generator. The charger is for charging the battery by supplying electric power generated by the generator to the battery, and includes a rectifier circuit for converting an AC voltage generated by the generator into a DC voltage. I have it.

Further, the signal communication means includes a wireless communication device that wirelessly communicates the output signal of each displacement sensor with an electronic device such as a computing unit arranged on the vehicle body side.

Further, the rotation angle detecting means is an absolute type encoder such as an optical type or a magnetic type which has been widely known from the past, and is supported and fixed directly to the outer ring 46 or indirectly via the cap 57 or the like. And a detection rotor that is directly or indirectly supported and fixed to the hub 47, and an output that changes as the detection stator and the detection rotor rotate relative to each other. Based on the signal, it is possible to measure how many (radians) the hub 47 is rotated from the origin position (initial setting value) of the outer ring 46.

Further, in the assembled state to the wheel supporting rolling bearing unit 45 shown in FIG. 13, the respective sensor units 14, the charger and the wireless communication device are provided with wiring 34 for power supply and signal transmission, respectively. Are electrically connected via a connector (not shown). Each of these wires 34 is drawn out from each of the sensor units 14 into a space existing between the inner peripheral surface of the large-diameter step portion 12 and the outer peripheral surface of the positioning cylindrical portion 58, and further, of the positioning cylindrical portion 58. It is drawn from the axially outer end opening of the positioning tubular portion 58 into the radially inner space of the hub 47 via the axially outer space.

In the case of the present example, when the hub 47 rotates together with the wheels 4 as the vehicle travels, the rotor supported and fixed to the hub 47 is opposed to the stator supported and fixed to the outer ring 46. By rotating, the generator generates electricity. Then, the AC voltage generated by the generator is converted into a DC voltage by the charger, and then the battery is charged.

The electric power charged in the battery is supplied to the sensor units 14 and 14 through the wires 34, and is also supplied to the wireless communication device and the encoder through wires (not shown). Then, each of the sensor units 14 and 14 generates an output signal corresponding to the load acting on the wheel 4, and the encoder generates an output signal indicating the rotation angle of the hub 47 with respect to the outer wheel 46. Output signals of the sensor units 14 and 14 are sent to the wireless communication device through the wires 34, and output signals of the encoder are sent through a wire (not shown). The output signal of each of the sensor units 14 and 14 and the encoder is output by the antenna forming the wireless communication device through the bottom plate made of a non-magnetic material forming the cap 57, and the computing unit is arranged on the vehicle body side. Is wirelessly transmitted to. As a result, as will be described later, this computing unit calculates the load acting on the wheel 4 from the output signals of the sensor units 14, 14 and the encoder, and uses it for the active safety technology of the vehicle.

Next, a calculation method for obtaining the load acting on the wheel 4 (tire 3 and wheel 1) based on the output signals of the sensor units 14 and 14 will be described.
In the case of this example, when a load (combined with a ground load, a front-rear load associated with acceleration or braking, etc.) acts on the wheel 4, the wheel 1 elastically deforms by an amount corresponding to this load. As a result, the positional relationship between the detection body 19 and the detected body 20 constituting each of the sensor units 14, 14 changes, and along with this, the output signals of the sensor units 14, 14 (the first planar coil). The output signal of 31 and the output signal of the second plane coil 32) change.

FIG. 12 shows the output signals (S _{1 to} S ₅ ) of the first plane coil 31 constituting each of the sensor units 14 and 14 when the wheel 4 is rotating while receiving a constant radial load ((S _{1 to} S ₅ )). The theoretical value is shown. The amplitude of the output signal (S _{1 to} S ₅ ) of each of the first planar coils 31 changes according to the magnitude of the radial load, and the phase also changes according to the direction of the radial load. Therefore, if the relationship between the magnitude of the radial load and the amplitude is investigated in advance, the magnitude of the radial load can be obtained from the amplitude by the calculator.

On the other hand, in the state where the wheel 4 is rotating while receiving an axial load in addition to the radial load, the output signal of the first plane coil 31 forming each of the sensor units 14 and 14 is added to the axial load. Based changes occur.
In this case, as described above, the magnitude of the radial load can be obtained by correcting the output of the first plane coil 31 using the output of the second plane coil 32.

Further, when the wheel 4 is rotating while receiving an axial load, the output signal of the second plane coil 32 constituting each of the sensor units 14 and 14 is changed in accordance with the direction and the magnitude of the axial load. Change. Therefore, if the relationship between the direction and magnitude of the axial load and the output signal of each of the second planar coils 32 is checked in advance, the arithmetic unit calculates the axial load from the output signal of each of the second planar coils 32. The direction and size can be calculated.

Further, in the case of the present example, the arithmetic unit determines the rotation angle of the hub 47 with respect to the outer ring 46 (the rotation angle of the rotation system with respect to the stationary system) and the first plane, which are obtained based on the output signal of the encoder. The direction of the radial load (direction in the stationary system) can be obtained by associating with the phase of the output signals (S _{1 to} S ₅ ) of the coil 31 (and each of the second planar coils 32). Furthermore, the ground contact load, which is the vertical component of this radial load, can also be obtained.
When the present invention is implemented, an ABS sensor (magnetic encoder+magnetic sensor) may be adopted (used) as the rotation angle detecting means instead of the absolute encoder as described above.

Further, in the case of this example, the radial outer end portion of the displacement take-out member 13 is supported in a cantilever manner on the radial outer end portion (rim portion 5) of the wheel 1, and the displacement take-out member is also provided. The detected body 20 constituting each of the sensor units 14, 14 is supported on the radially inner end of 13 (the annular connecting portion 16), and the radially inner end of the wheel 1 (mounting portion 7) is supported. A sensor case 18 (detector 19) forming each of the sensor units 14, 14 is supported. Therefore, when the load acting on the wheel 4 changes, the amount of change in the positional relationship between the detected body 20 and the detected body 19 forming each of the sensor units 14, 14 is the radial direction of the wheel 1. The amount of change in the positional relationship between the outer end portion and the radially inner end portion becomes large, and the output of each of the sensor units 14 and 14 (the output of the first planar coil 31 and the output of the second planar coil 32). The amount of change in (output) also increases. Further, in the case of the present example, the detected body 20 and the detected body 19 constituting each of the sensor units 14, 14 are arranged close to each other based on the existence of the displacement extracting member 13. Therefore, the outputs of the sensor units 14, 14 (the output of the first plane coil 31 and the output of the second plane coil 32) can be increased. Therefore, in the case of this example, the reliability of the measurement of the load can be easily ensured.

Further, in the case of the present example, each of the sensor units 14 and 14 communicates the inside and the outside of the sensor case 18 with an O-ring 21 provided between the sensor case 18 and the detected body 20. The gap is sealed. More specifically, the insertion position of the detected body 20 (rod portion 35) with respect to the sensor case 18 is sealed by an O-ring 21. Therefore, it is possible to prevent foreign matter from entering the inside of the sensor case 18 through the insertion portion. Therefore, it is possible to prevent the foreign matter from entering between the detection body 19 and the detected body 20, and also in this respect, it is possible to easily ensure the reliability of the measurement.

Further, in the case of the present example, the structure of the insertion position of the detected body 20 with respect to the sensor case 18 is such that the inner peripheral surface of the cylindrical portion 25 and the outer peripheral surface of the cylindrical portion 38 are cylindrical surfaces. It has a loose fitting structure with the surface. Therefore, the O-ring 21 having a simple shape can be used as a sensor seal that seals the insertion portion.

Further, in the case of this example, each of the sensor units 14 and 14 has a seal structure by the O-ring 21 individually. Therefore, the sealing area of each sensor unit 14, 14 can be minimized as compared with the case where a large-scale sealing structure for collectively sealing each sensor unit 14, 14 is adopted. Therefore, the reliability of the sealing performance of each of the sensor units 14, 14 can be sufficiently ensured, and the assembling property of the entire wheel with the sensing device can be improved.

Further, in the case of the wheel with the sensing device of the present example, as shown in FIG. 13, power supply and signal transmission are performed through the wheel supporting rolling bearing unit 45 to each of the sensor units 14 mounted on the wheel 1. When connecting the reliable wiring 34, the length of the wiring 34 from the wheel supporting rolling bearing unit 45 to each of the sensor units 14 can be shortened. That is, in the case of this example, a configuration in which the sensor units 14 are supported at the radially inner ends of the wheel 1 and the displacement take-out member 13 (detection of each sensor unit 14 at the mounting portion 7 of the wheel 1) The structure that supports the body 19) is adopted. Therefore, in a state where the mounting portion 7 of the wheel 1 is fixedly coupled to the hub 47 which constitutes the wheel supporting rolling bearing unit 45, the distance from the wheel supporting rolling bearing unit 45 to each of the sensor units 14 is set. Can be shortened. Therefore, the length of the wiring 34 from the wheel supporting rolling bearing unit 45 to each of the sensor units 14 can be shortened. As a result, the wirings 34 can be easily laid, and noise is less likely to be mixed in the signal transmitted through the wirings 34.

Further, in the case of the present example, each of the sensor units 14 is supported at the radial inner end of the wheel 1 and the displacement take-out member 13 close to the center of rotation (the annular coupling portion 16 is provided with the above-mentioned member). Since the detection body 20 is supported), the adverse effect of centrifugal force on the sensor accuracy can be suppressed as compared with the case where each of the sensor units 14 is supported at the radially outer end portion far from the center of rotation.

Further, in the case of this example, the sensor case 18 (and the screws 42, 42) constituting each of the sensor units 14 are arranged inside the inner diameter side holding concave portion 11 provided on the mounting surface 9 of the wheel 1. doing. Therefore, in a state where the mounting portion 7 of the wheel 1 is coupled and fixed to the hub 47, that is, in a state where the mounting surface 9 is in contact with the axially outer surface of the radial inner half of the brake rotor 44, It is possible to prevent the sensor cases 18 (and the screws 42, 42) from coming into contact with the axially outer side surface of the radial inner half of the brake rotor 44. Therefore, it is possible to make it difficult for frictional heat generated during braking to be transmitted from the brake rotor 44 to the sensor units 14, 14. Further, in a state where the mounting portion 7 of the wheel 1 is fixedly coupled to the hub 47, the periphery is surrounded by the inner surface of each of the inner diameter side holding recesses 11 and the axial outer surface of the radially inner half of the brake rotor 44. The sensor case 18 that constitutes each of the sensor units 14 is arranged in the enclosed space. Therefore, for example, it is possible to effectively prevent the stepping stones that have jumped up from the road surface while the vehicle is traveling, hitting the sensor case 18.

[Second Example of Embodiment]
A second example of the embodiment of the present invention will be described with reference to FIG.
In the case of the present example, only the structure of the combination of the detection body 19a and the detection target body 20 constituting the sensor unit 14a differs from the case of the first example of the above-described embodiment. Incidentally, in FIG. 14, the illustration of the sensor case forming the sensor unit 14a is omitted.

In the case of the present example, the structure of the detected body 20 is the same as that of the first example of the above-described embodiment, but the other end surface in the longitudinal direction of the rod portion 35 constituting the detected body 20 { The right end surface in FIG. 14, which is the inner end surface in the radial direction of the wheel 1 (see FIGS. 3 and 13), is a flat first detected portion 60 orthogonal to the longitudinal direction. Along with this, the second radial direction side surface of the semi-cylindrical portion 39 of the rod portion 35 (the lower side surface of FIG. 14B which is the inner side surface in the axial direction of the wheel 1) is detected as a flat second detection target. Part 61.

On the other hand, the detection body 19a has a first substrate 62 and a second substrate 63 which are held and fixed in an L-shaped state inside a sensor case (not shown). Of these, the first substrate 62 has the first flat coil 31 mounted on one side surface in the thickness direction (the outer side surface in the radial direction of the wheel 1, the left side surface in FIG. 14) of the detected body 20. The first detected portion 60 is closely opposed to the first detected portion 60. In addition, the second substrate 63 has the second flat coil 32 mounted on one side in the thickness direction {the upper side of FIG. The second detected part 61 of the detection body 20 is closely opposed.

In the case of the present example, a radial load acts on the wheel 1, so that the detected body 20 and the sensor case (the detected body 19a) are relatively positioned with respect to the longitudinal direction of the sensor case (β direction in FIG. 14). When displaced, the facing distance between the second detected portion 61 and the second planar coil 32 does not change, but the facing distance between the first detected portion 60 and the first planar coil 31 changes. While the output of the second plane coil 32 remains constant, only the output of the first plane coil 31 changes.

Further, when an axial load acts on the wheel 1, the detected body 20 and the sensor case (the detection body 19a) are displaced relative to each other in the thickness direction of the sensor case (direction α in FIG. 14). The facing distance between the first detected portion 60 and the first planar coil 31 does not change, but the facing distance between the second detected portion 61 and the second planar coil 32 changes, so the first While the output of the plane coil 31 remains constant, only the output of the second plane coil 32 changes.

Further, in the case of the present example, even when the detected body 20 and the sensor case (the detection body 19a) are relatively displaced in the lateral direction (γ direction in FIG. 14) of the sensor case, The facing area between the one detected part 60 and the first planar coil 31 does not change (the output of the first planar coil 31 does not change), and the second detected part 61 and the second planar coil 31 do not change. The dimensions of each part are regulated so that the area facing 32 is not changed (the output of the second planar coil 32 is not changed).

That is, in the case of the present example, the first plane coil 31 functions as a displacement sensor having sensitivity only in the radial direction (β direction in FIG. 14), and the second plane coil 32 is in the axial direction (see FIG. 14). It functions as a displacement sensor with sensitivity only in the α direction. Therefore, in the case of this example, the relative displacement amount in the thickness direction between the detected body 20 and the detection body 19a is obtained by the output of the second planar coil 32, and the relative displacement amount in the longitudinal direction is the same as the above. It is obtained by the output of the first plane coil 31.
Other configurations and operations are the same as in the case of the first example of the above-described embodiment.

[Third Example of Embodiment]
A third example of the embodiment of the present invention will be described with reference to FIGS.
In the case of this example, the structures of the detection body 19b and the detected body 20a that form the sensor unit 14b are slightly different from those of the first example of the above-described embodiment.

That is, in the case of the present example, the detection body 19b sandwiches the second planar coil 32 on one side surface (upper side surface of FIGS. 15 and 17) of the substrate 30 in the thickness direction (α direction of FIGS. 15 to 17). A third plane coil 64 is mounted on a portion located on the opposite side to the first plane coil 31 in the longitudinal direction (β direction in FIGS. 15 to 17). That is, these first to third plane coils 31, 32, 64 are arranged in series at a predetermined interval in the longitudinal direction. The third plane coil 64 is also connected to a circuit (not shown) mounted on one side surface in the thickness direction of the substrate 30, like the first and second plane coils 31 and 32.

Further, in the case of the present example, of the semi-cylindrical portion 39a of the rod portion 35 that constitutes the detected body 20a, the short side direction (γ in FIGS. 15 to 17) of the portion closer to one end (the left end in FIGS. Direction) A notch 65 is provided in one half (the front half of the paper in FIGS. 15 and 17, the lower half in FIG. 16). Then, in the detected portion 41 which is the other radial side surface (lower side surface of FIGS. 15 and 17) of the semi-cylindrical portion 39a, a portion adjacent to the cutout 65 in the lateral direction is defined by the third plane. At least a part of the coil 64 on the other side in the lateral direction (the back side of the paper in FIGS. 15 and 17 and the upper side in FIG. 16) is made to closely face.

In the case of the present example having the above-described configuration, the load 1 to be detected (see FIG. 3 and FIG. 13) causes a radial load to act, so that the detected body 20a and the sensor case 18 (the detection body 19b) are When the sensor case 18 is relatively displaced in the longitudinal direction (β direction), the facing area between the detected part 41 and the second planar coil 32 and the facing area between the detected part 41 and the third planar coil 64. Does not change, respectively, but the facing area between the detected part 41 and the first planar coil 31 changes. Therefore, only the output of the first plane coil 31 changes while the outputs of the second and third plane coils 32 and 64 remain constant.

Further, when the axial load acts on the wheel 1 (see FIGS. 3 and 13), the detected body 20a and the sensor case 18 (the detected body 19b) are separated from each other in the thickness direction (α Direction), the facing distance between the detected portion 41 and each of the first to third planar coils 31, 32, 64 changes, so that the first to third planar coils 31, 32, 64 are changed. Output changes.

Further, in the case of this example, when a torque acts on the wheel 1 (see, for example, FIG. 2), the wheel 1 is elastically twisted in the rotational direction by an amount corresponding to the torque. Along with this elastic twist, a relative displacement in the rotational direction occurs between the mounting portion 7 and the annular coupling portion 16 that constitutes the displacement extracting member 13 that is coupled to the rim portion 5. As a result, the sensor case 18 (the detection body 19b) supported by the mounting portion 7 and the detected body 20a supported by the annular coupling portion 16 are moved in the lateral direction (γ Direction), the facing area between the detected part 41 and the first planar coil 31 and the facing area between the detected part 41 and the second planar coil 32 do not change, respectively. The facing area between the detected part 41 and the third planar coil 64 changes. Therefore, only the output of the third plane coil 64 changes while the outputs of the first and second plane coils 31 and 32 remain constant. The direction and the magnitude of the change in the output of the third planar coil 64 caused by the action of the torque in this manner depend on the direction and the magnitude of the torque.

That is, in the case of the present example, the first plane coil 31 functions as a displacement sensor having sensitivity in the radial direction (β direction) and the axial direction (α direction), and the second plane coil 32 functions as the axial direction ( The third flat coil 64 functions as a displacement sensor having only sensitivity in the α direction, and the third planar coil 64 has a displacement sensor having sensitivity in the circumferential direction (γ direction, which is the lateral direction) and the axial direction (α direction). Function as.

When the relative displacements in the above three directions (radial direction, axial direction, circumferential direction) occur at the same time, the relative displacement amount in the axial direction (α direction) is obtained from the output of the second planar coil 32. Similarly, the relative displacement amount in the radial direction (β direction) is obtained by correcting the output of the first plane coil 31 using the output of the second plane coil 32. Similarly, the amount of relative displacement in the circumferential direction (γ direction) is obtained by correcting the output of the third plane coil 64 using the output of the second plane coil 32.

In the case of this example, the second planar coil 32 corresponds to “any one planar coil of the plurality of planar coils” described in the claims, and the first planar coil 31 and The third planar coil 64 corresponds to the "remaining planar coil of the plurality of planar coils" recited in the claims.

In the structure of this example, a radial load acts on the wheel 1 to cause a relative displacement between the mounting portion 7 and the annular connecting portion 16 in the acting direction of the radial load. Also in this case, the sensor case 18 (the detection body 19b) and the detected body 20a may be relatively displaced in the lateral direction (γ direction) of the sensor case 18.
However, the relative displacement in the lateral direction (γ direction) due to such a radial load and the relative displacement in the lateral direction (γ direction) due to the torque described above are separated by using the rotation angle information of the wheel 1. You can do it.
That is, the relative displacement in the lateral direction (γ direction) due to the radial load described above changes according to the rotation angle of the wheel 1. On the other hand, since the relative displacement in the lateral direction (γ direction) due to the torque does not depend on the rotation angle of the wheel 1, by combining the output signals of the plurality of sensor units 14b and the rotation angle information of the wheel 1, the radial displacement can be improved. Relative displacement due to load and relative displacement due to torque can be separated.
Other configurations and operations are the same as in the case of the first example of the above-described embodiment.

[Fourth Example of Embodiment]
A fourth example of the embodiment of the present invention will be described with reference to FIGS.
In the case of this example, the following points regarding the sensor unit 14c differ from the case of the third example of the above-described embodiment.

That is, in the case of the present example, with respect to the sensor unit 14c, the first to third planar coils 31, 32, 64 mounted on one side surface in the thickness direction (the α direction in FIG. 19) of the substrate 30 forming the detection body 19c. Of these, the first and second planar coils 31 and 32 are arranged at the same position in the lateral direction (γ direction in FIG. 18) at two positions separated in the longitudinal direction (β direction in FIGS. 18 and 19). At the same time, the third planar coil 64 is disposed between the first and second planar coils 31 and 32 in the longitudinal direction, and on one side of the first and second planar coils 31 and 32 in the lateral direction ( It is arranged at a position deviated to the lower side of FIG. 18.

Further, in the case of this example, as for the sensor unit 14c, the same detected object 20 as that in the case of the first example of the above-described embodiment is used. Then, in the semi-cylindrical portion 39 of the rod portion 35 that constitutes the detection target 20, one side portion in the short-side direction of the intermediate portion in the longitudinal direction is at least the other side in the short-side direction of the third plane coil 64 (Fig. The upper part of 18) is made to face a part of it closely.

As described above, in the case of the present example, among the first to third planar coils 31, 32, 64, in the portion between the first and second planar coils 31, 32 with respect to the longitudinal direction (β direction). The arranged third plane coil 64 is arranged at a position displaced to one side with respect to the first and second both plane coils 31 and 32 in the lateral direction (γ direction). In the case of this example having such a configuration, the first to third planar coils 31, 32, 64 are arranged in series in the longitudinal direction (β direction) as in the third example of the above-described embodiment. Compared with the above, when the interval between the adjacent planar coils is set to a predetermined length, the longitudinal range in which the first to third planar coils 31, 32, 64 are present can be shortened. Therefore, the dimension of the sensor unit 14c in the longitudinal direction can be shortened accordingly.
Other configurations and actions are similar to those of the first and third examples of the above-described embodiment.

The wheel with a sensing device of the present invention is not limited to the wheel supporting rolling bearing unit for the driven wheel, but can be used by being assembled to the wheel supporting rolling bearing unit for the driving wheel.
When carrying out the present invention, the wheel is not limited to the one-piece structure integrally formed by casting as a whole, but may have a multi-piece structure in which a plurality of parts are joined together by welding, screwing, or the like. ..
When the present invention is carried out, the radial inner end of the displacement take-out member may be supported on the radially inner end side of the wheel, and the radial outer end of the displacement take-out member may be a free end. ..

When the present invention is carried out, with respect to the sensor unit, of the detection body and the detection body, the detection body is arranged inside the sensor case while being prevented from relative displacement with the sensor case. It is also possible to use the above-mentioned component as a component, and the detection body in a state where the relative displacement with respect to the sensor case is possible, and a part of itself is the other component positioned outside the sensor case.
When carrying out the present invention, it is also possible to adopt a configuration in which the sensor case is fixed to the displacement extracting member and the other component is fixed to the wheel.
When the present invention is implemented, the form (shape, pattern, etc.) of the planar coil that is the detection element can be appropriately adopted.

In the case where a wheel support rolling bearing unit to which the wheel with the sensing device of the present invention is assembled is provided with power supply means for supplying power to the sensor and signal transmission means for transmitting the output signal of the sensor to the vehicle body side, these means Are not limited to those used in the above-described respective embodiments, and various types (such as an electromagnetic induction type or resonance type wireless power supply device and a contact type communication power supply means) can be used.
Further, the wheel supporting rolling bearing unit to which the wheel with the sensing device of the present invention is assembled may be a conventionally known wheel supporting rolling bearing unit which is not provided with a power supply means or a signal communication means. In this case, the electric power to the sensor unit can be supplied from, for example, a battery (battery) supported by the wheel, and the output signal of the sensor unit is transmitted to an arithmetic unit on the vehicle body side by, for example, a wireless antenna supported by the wheel. You can do it.
Further, the wheel with the sensing device of the present invention is not limited to the load acting on the wheel, and other inputs (acceleration, temperature, etc.) that cause deformation of the wheel can be measured in the same manner as the load. .. Further, the wheel with a sensing device of the present invention can be used simply for measuring the relative displacement between the radial one end side portion and the radial other end side portion of the wheel.

DESCRIPTION OF SYMBOLS 1 Wheel 2 Sensing device 3 Tire 4 Wheel 5 Rim part 6 Disc part 7 Mounting part 8 Spoke 9 Mounting surface 10 Mounting hole 11 Inner diameter side holding recessed part 12 Large diameter step part 13 Displacement extraction member 14, 14a-14c Sensor unit 15 Pseudo spoke 16 annular connection part 17 outer diameter side holding concave part 18 sensor case 19, 19a-19c detection body 20, 20a detected body 21 O-ring 22 first case part 23 second case part 24 main body part 25 cylindrical part 26 semi-cylindrical shape Part 27 Sleeve 28 Fixing flange 29 Through hole 30 Substrate 31 First planar coil 32 Second planar coil 33a, 33b Protrusion 34 Wiring 35 Rod part 36 Fixing part 37 Through hole 38 Cylindrical part 39, 39a Semi-cylindrical part 40 Engagement Groove 41 Detected part 42 Screw 43 Screw 44 Brake rotor 45 Wheel support rolling bearing unit 46 Outer ring 47 Hub 48 Balls 49a, 49b Outer ring track 50 Stationary side flange 51 Hub body 52 Inner ring 53a, 53b Inner ring track 54 Rotation side flange 55 Mounting hole 56 Seal ring 57 Cap 58 Positioning cylinder portion 59 Mounting hole 60 First detected portion 61 Second detected portion 62 First substrate 63 Second substrate 64 Third planar coil 65 Notch

Claims (5)

A wheel that constitutes a wheel and a sensing device are provided,
The sensing device has a displacement extraction member and a sensor unit,
The displacement take-out member has one end in the radial direction supported by a part on the one end in the radial direction of the wheel, and the other end in the radial direction is a free end,
The sensor unit has a sensor case, a detected body having a detected portion, and a detected body having a detection element whose output changes in accordance with a change in the positional relationship with the detected portion. ,
Either one of the detection body and the detected body is disposed inside the sensor case in a state in which relative displacement with the sensor case is blocked.
The other part of the detection body and the detection body faces the detection part and the detection element inside the sensor case in a state where relative displacement with the sensor case is possible. Together with that, a part of itself is located outside the sensor case,
The sensor case is fixed to either one of the radial other end portion of the wheel and the radial other end portion of the displacement extracting member,
A portion of the other component located outside the sensor case is fixed to the other portion of the radial other end portion of the wheel and the radial other end portion of the displacement extracting member. Wheel with a sensing device. While the detection body is the one component, the detected body is the other component,
The detected portion is made of a conductive material,
The detection body has a plurality of planar coils, each of which is the detection element, and one to a plurality of substrates on which the plurality of planar coils are mounted, and any one of the plurality of planar coils. The two planar coils change the output when the positional relationship with the detected part changes at least in a predetermined direction, and the remaining planar coils of the plurality of planar coils are the same as the detected part. The wheel with a sensing device according to claim 1, wherein the output changes when at least the positional relationship of the two changes in a direction peculiar to itself different from other planar coils. Any one of the planar coils faces the detected part in the predetermined direction, and even when the positional relationship with the detected part changes in a direction different from the predetermined direction, the predetermined coil is used. The facing area with respect to the detected part in the direction does not change,
The remaining planar coil faces the detected portion in the predetermined direction, and the predetermined direction is changed as the positional relationship with the detected portion changes in a direction peculiar to itself. The sensing device-equipped wheel according to claim 2, wherein a facing area of the sensing device with respect to the detected portion changes. The sensor unit has a sensor seal that is provided between the sensor case and the other component and seals a gap that communicates the inside and the outside of the sensor case. A wheel with a sensing device described in any one of 1. The sensing device has a plurality of the sensor units,
The wheel with a sensing device according to any one of claims 1 to 4, wherein the plurality of sensor units are arranged apart from each other in a circumferential direction of the wheel.

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