JP7108437B2 - In-wheel motor drive - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-wheel motor drive device, and more particularly to an in-wheel motor drive device equipped with a wheel speed detection device for detecting rotation of wheels.

In recent years, the number of automobiles equipped with ABS (anti-lock braking system) is increasing in order to improve safety. The ABS uses a wheel speed detector that detects the rotation of the wheels. The wheel speed detection device includes a sensor target provided on a rotating portion that rotates integrally with the wheel, and a rotation sensor (wheel speed sensor) attached to face the sensor target. A detection signal from the rotation sensor is transmitted to a control device attached to the vehicle body, and the control device controls the brake mechanism, such as adjusting the brake hydraulic pressure of the wheels. Such a rotation sensor is used not only for ABS but also for ESC (electronic stability control).

Japanese Patent Laying-Open No. 2013-152023 (Patent Document 1) discloses a configuration in which a pulsar ring (sensor target) is arranged in a hat portion of a brake disc. In Document 1, the pulsar ring includes a flange portion that extends in the radial direction and is attached to the hat portion, and a detected portion that is bent from the flange portion and extends in the axle direction and faces the rotation sensor.

JP 2013-152023 A

In order to avoid interference between the in-wheel motor drive device and the inner wall of the wheel housing formed on the outside of the vehicle body in the vehicle width direction without sacrificing the vehicle interior space, the length of the in-wheel motor drive device in the axle direction is shortened. There is a need to. In addition, when the in-wheel motor drive device is mounted on the steerable wheels, in order to arrange the device without sacrificing the steering angle, the length of the in-wheel motor drive device in the axle direction is larger than when it is mounted on the non-steerable wheels. need to be even shorter.

The configuration in which the pulsar ring is arranged in the hat portion of the brake disc as in Patent Document 1 is advantageous in that it does not affect the axial length of the in-wheel motor drive device.

Further, in Japanese Patent Laid-Open No. 2002-100001, a holding member that holds a rotation sensor is provided with a position adjusting portion, which enables adjustment of the gap between the detected portion of the pulsar ring and the rotation sensor. Errors can be allowed. As a result, deterioration in detection accuracy of the rotation sensor can be prevented.

However, in Patent Document 1, since the rotation sensor is attached to the casing of the in-wheel motor drive device, there are cases where the number of parts intervening from the attachment portion of the rotation sensor to the detected portion increases. In , it becomes difficult to manage the gap between the detected portion and the rotation sensor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its object is to be able to arrange a wheel speed detection device without affecting the axial length of an in-wheel motor drive device, and It is an object of the present invention to provide an in-wheel motor drive device capable of easily managing a gap between a detected part and a rotation sensor.

An in-wheel motor drive device according to one aspect of the present invention is coaxially coupled to a brake rotor having a hat portion formed so as to be recessed outward in the vehicle width direction, an inner ring that rotates integrally with the brake rotor, and an inner ring that is non-rotatably fixed to the brake rotor. and a wheel hub bearing assembly including an outer ring. This in-wheel motor drive device is arranged in a hat portion of a brake rotor and includes a detected portion that causes a magnetic flux change in the circumferential direction, and an outer ring of a wheel hub bearing portion or an outer ring so as to face the detected portion. and a rotation sensor attached to a hub support member that supports a wheel speed detection device.

Preferably, the wheel speed detection device further includes a holding member for attaching the rotation sensor to the flange portion of the outer ring or the hub support member.

Preferably, at least part of the holding member is arranged radially inward of the flange portion of the outer ring or the outer circumference of the hub support member.

Preferably, the holding member has a plane portion parallel to the detected portion, and the rotation sensor is fixed to the plane portion of the holding member.

It is desirable that the detected portion and the planar portion of the holding member are arranged so as to be perpendicular to the axis of the wheel.

In this case, a fitting hole for fitting the rotation sensor may be provided in the flange portion of the outer ring or the hub supporting member.

The detected portion and the planar portion of the holding member may be arranged obliquely with respect to the axis of the wheel.

Preferably, the holding member is fixed to the flange portion of the outer ring or the hub support member by a fastening member that is passed from the outside in the vehicle width direction.

According to the present invention, the wheel speed detection device can be arranged without affecting the axial length of the in-wheel motor drive device. In addition, it becomes possible to easily manage the gap between the detected portion and the rotation sensor.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically the basic composition of the in-wheel motor drive device which concerns on Embodiment 1 of this invention. FIG. 2 is a front view schematically showing the attachment structure of the rotation sensor according to Embodiment 1 of the present invention; FIG. 4 is a cross-sectional view schematically showing a mounting structure of a rotation sensor in Modification 1 of Embodiment 1 of the present invention; FIG. 4 is a front view schematically showing a mounting structure of a rotation sensor according to Modification 1 of Embodiment 1 of the present invention; FIG. 7 is a cross-sectional view schematically showing a mounting structure of a wheel hub bearing portion and a rotation sensor in Modification 2 of Embodiment 1 of the present invention; FIG. 7 is a front view schematically showing a mounting structure of a wheel hub bearing portion and a rotation sensor in Modification 2 of Embodiment 1 of the present invention; FIG. 7 is a cross-sectional view schematically showing a mounting structure of a wheel hub bearing portion and a rotation sensor in Modification 3 of Embodiment 1 of the present invention; FIG. 10 is a front view schematically showing a mounting structure of a wheel hub bearing portion and a rotation sensor in Modification 3 of Embodiment 1 of the present invention; FIG. 10 is a diagram schematically showing a positioning fitting portion provided on an outer ring flange in Modification 3 of Embodiment 1 of the present invention; FIG. 7 is a cross-sectional view schematically showing a mounting structure of a wheel speed detection device according to Embodiment 2 of the present invention; FIG. 8 is a perspective view of a brake disc to which a pulsar ring is attached, as viewed from the outside in the vehicle width direction, according to Embodiment 2 of the present invention; FIG. 7 is a perspective view of a brake disc to which a pulsar ring is attached, as viewed from the inside in the vehicle width direction, according to Embodiment 2 of the present invention;

An embodiment of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

The in-wheel motor drive device according to the present embodiment is equipped with a wheel speed detection device that detects rotation of the wheels. The wheels are those of passenger vehicles such as electric or hybrid vehicles.

<Embodiment 1>
(Regarding a basic configuration example of an in-wheel drive device)
First, with reference to FIGS. 1 and 2, a basic configuration example of an in-wheel motor drive device 1 according to the present embodiment and peripheral structures thereof will be described.

FIG. 1 is a developed sectional view showing the in-wheel motor drive device 1. FIG. FIG. 2 is a schematic front view showing the in-wheel motor drive device 1, showing a state in which the in-wheel motor drive device 1 is viewed from the outside in the vehicle width direction. In FIG. 1 , the right side of the paper represents the inner side in the vehicle width direction (inboard side), and the left side of the paper represents the outer side in the vehicle width direction (outboard side). The cross section shown in FIG. 1 is a developed plane connecting the plane including the axis M and the axis N shown in FIG. 2 and the plane including the axis N and the axis O in this order. In FIG. 2, the right side of the paper indicates the rear of the vehicle, the left side of the paper indicates the front of the vehicle, the upper side of the paper indicates the upper side of the vehicle, and the lower side of the paper indicates the lower side of the vehicle.

The in-wheel motor drive device 1 includes a wheel hub bearing portion 11 provided at the center of a wheel, a motor portion 21 that rotationally drives a motor shaft 22, and decelerates the rotation of the motor shaft 22 and transmits it to the wheel hub bearing portion 11. and a deceleration unit 31 . The speed reducer that constitutes the speed reducer 31 is, for example, a triaxial parallel shaft gear speed reducer. The motor portion 21 and the reduction portion 31 are arranged offset from the axis O of the wheel hub bearing portion 11 . The axis O extends in the vehicle width direction and coincides with the axle direction.

The wheel hub bearing portion 11, the deceleration portion 31, and the motor portion 21 are housed inside the wheel (inner hollow region), ie, the wheel W. As shown in FIG. In addition, at least part of the motor section 21 may be arranged inside the wheel W in the vehicle width direction in order to avoid interference with the wheel. The in-wheel motor drive device 1 is connected with the wheel W to drive the wheel. A wheel is composed of a wheel W and a tire fitted to the outer periphery thereof. In the following description, one side in the direction of the axis O means the outside in the vehicle width direction, and the other side in the direction of the axis O means the inside in the vehicle width direction.

A casing 10 of the entire in-wheel motor drive device 1 is configured by a motor housing 20 that forms an outer shell of the motor portion 21 and a speed reducer housing 30 that forms an outer shell of the reduction portion 31 and the wheel hub bearing portion 11 .

The wheel hub bearing portion 11 has an inner ring 12 as a rotating element, an outer ring 13 as a fixed element, and a plurality of rolling elements 14 arranged in an annular gap between the inner and outer rings. A flange (hereinafter referred to as "outer ring flange") 13f is erected on the outer peripheral surface of the outer ring 13. As shown in FIG. The shape of the outer ring flange 13f is star-shaped when viewed from the front, and the outer ring flange 13f includes a plurality of (five) protrusions (connecting portions) 13a provided at intervals in the circumferential direction. The outer diameter of the outer ring 13 is maximized at the protrusions 13a and minimized at a portion (hereinafter referred to as a "recess") 13b located between the protrusions 13a adjacent in the circumferential direction.

A through hole is formed in the protruding portion 13a of the outer ring 13 . Each through hole extends parallel to the axis O, and a bolt 83 is passed from one side in the axis O direction. A shaft portion of each bolt 83 is screwed into a female screw hole drilled in the front portion 30 f of the speed reducer housing 30 . As a result, the outer ring 13 is connected and fixed to the front portion 30f. The outer ring 13 is fixed to a carrier (not shown) at its lower end.

The inner ring 12 is a cylindrical body longer than the outer ring 13 and is passed through the center hole of the outer ring 13 . That is, the outer ring 13 is arranged on the outer circumference of the inner ring 12 . A flange (hereinafter referred to as an “inner ring flange”) 12f is formed at one end of the inner ring 12 in the direction of the axis O, which projects outward from the outer ring 13 in the vehicle width direction. The inner ring flange 12f is arranged away from the outer ring flange 13f on one side in the axis O direction.

When viewed from the front, the shape of the inner ring flange 12f is a petal shape. 12b. The outer diameter of the inner ring 12 is maximized at the protrusion 12a and minimized at the valley 12b.

A protrusion 12a of an inner ring flange 12f as a hub flange constitutes a coupling seat for coaxial coupling with the brake disc 5 and a wheel (not shown). The inner ring 12 is coupled with the wheel at the protrusion 12a of the inner ring flange 12f by the wheel bolt 82, and rotates integrally with the wheel. The wheel bolt 82 is passed through the through hole 12h of the projecting portion 12a from the other side in the direction of the axis O. As shown in FIG.

The brake disc 5 has a rotor portion 51 sandwiched between the brake pads 80 supported by the brake caliper 81, and a hat portion 52 formed to be recessed outward in the vehicle width direction from the inner diameter side end portion of the rotor portion 51. ing. The rotor portion 51 and the hat portion 52 are integrally formed.

The hat portion 52 includes a radially extending bottom wall portion 53 and an outer peripheral portion 54 connected to the outer peripheral edge portion of the bottom wall portion 53 and having a cylindrical inner diameter surface. It defines a cylindrical hollow space. Since the outer peripheral portion 54 corresponds to the annular stepped portion formed on the brake disc 5 , the outer peripheral portion 54 is hereinafter also referred to as the annular stepped portion 54 . The bottom wall portion 53 corresponds to an inner diameter region located on the inner diameter side of the annular step 54 . The rotor portion 51 corresponds to an outer diameter region located on the outer diameter side of the annular step 54 .

A plurality of through holes are provided in the bottom wall portion 53 of the hat portion 52, and the wheel bolts 82 pass through the through holes 12h provided in the projecting portion 12f of the inner ring 12 and these through holes. As shown in FIG. 2, the maximum outer diameters of the inner ring 12 and the outer ring 13 of the wheel hub bearing portion 11 are smaller than the diameter of the annular step 54 of the brake disc 5 (that is, the inner diameter of the outer peripheral portion 54 of the hat portion 52). . The maximum outer diameter of outer ring 13 is larger than the maximum outer diameter of inner ring 12 . When viewed in the direction of the axis O, the head of the bolt 83 is located radially outward of the inner ring flange 12f and does not overlap the inner ring flange 12f.

The motor portion 21 has a motor shaft (motor rotation shaft) 22, a rotor 23, a stator 24, and the motor housing 20, which are arranged in this order from the axis M of the motor portion 21 to the outer diameter side. The motor unit 21 is an inner rotor/outer stator type radial gap motor, but may be of another type. For example, although not shown, the motor section 21 may be an axial gap.

An axis M around which the motor shaft 22 and the rotor 23 rotate is separated from the axis O of the wheel hub bearing portion 11 in the longitudinal direction of the vehicle and extends parallel to the axis O. As shown in FIG. In other words, the motor portion 21 is offset from the axis O of the wheel hub bearing portion 11, for example, to the front of the vehicle. Both ends of the motor shaft 22 are rotatably supported by the motor housing 20 via rolling bearings 27 and 28 .

The speed reduction unit 31 is a three-axis parallel shaft type gear speed reducer, and includes an output gear 36 coaxially coupled to the inner ring 12, an input gear 32 coaxially coupled to the motor shaft 22 of the motor unit 21, and an input gear. It has a plurality of intermediate gears 33 and 35 for transmitting rotation from 32 to an output gear 36 and the speed reducer housing 30 described above.

The input gear 32 is a small-diameter external gear, and has a large number of teeth formed on the outer periphery of the other end in the axial direction of the shaft portion 32s arranged along the axis M. As shown in FIG. The axis of the shaft portion 32s coincides with the axis M. As shown in FIG. The shaft portion 32s is fitted to the motor shaft 22 so that the shaft portion 32s and the motor shaft 22 cannot rotate relative to each other by inserting the projecting portion 22p formed at one end of the motor shaft 22 in the direction of the axis M into the center hole 32h of the shaft portion 32s.

The shaft portion 32s is an input shaft, and is rotatably supported by the speed reducer housing 30 on both end sides of the input gear 32 via rolling bearings 32m and 32n. The small-diameter input gear 32 meshes with the first intermediate gear 33, which becomes a large-diameter external gear. The intermediate gear 33 is coaxially coupled by an intermediate shaft 34 to a second intermediate gear 35 which is a small-diameter external gear. Both ends of the intermediate shaft 34 are rotatably supported by the speed reducer housing 30 via rolling bearings 34m and 34n.

An axis N passing through the center of the intermediate shaft 34 extends parallel to the axis O of the wheel hub bearing portion 11 and is positioned between the axis O and the axis M in the vehicle front-rear direction. In this manner, the speed reducing portion 31 is arranged offset from the wheel hub bearing portion 11 . The axis N of the deceleration section 31 is arranged above the axis O. As shown in FIG.

The small diameter second intermediate gear 35 meshes with the large diameter output gear 36 . The output gear 36 is an external gear provided coaxially with the output shaft 15 . The output shaft 15 is rotatably supported by the front portion 30f of the speed reducer housing 30 via a rolling bearing 36m on the one side of the output gear 36 in the direction of the axis O. As shown in FIG. The output shaft 15 is rotatably supported by the rear wall portion 30b of the speed reducer housing 30 via a rolling bearing 36n on the other side of the output gear 36 in the direction of the axis O. As shown in FIG.

When electric power is supplied to the coil 26 from the outside of the in-wheel motor drive device 1 , the rotor 23 of the motor section 21 rotates, and rotation is output from the motor shaft 22 to the reduction section 31 . The deceleration section 31 decelerates the rotation input from the motor section 21 to the input shaft 32 s and outputs the rotation from the output shaft 15 to the wheel hub bearing section 11 . The inner ring 12 of the wheel hub bearing portion 11 rotates at the same rotational speed as the output shaft 15 to drive a wheel (road wheel W) (not shown) attached and fixed to the inner ring 12 .

The wheel speed detection device 6 according to the present embodiment detects the wheel speed by detecting the rotation of the brake disc 5 coaxially coupled to the inner ring 12 as a wheel hub.

<Regarding the wheel speed detector>
The wheel speed detector 6 will be described in detail with reference to FIGS. 1 and 2. FIG. The wheel speed detection device 6 includes a detected portion 61 that is provided on a rotating portion and that causes a change in magnetic flux in the circumferential direction, and a rotation sensor 62 that is provided on a fixed portion. Wheel speed detection device 6 in the present embodiment employs, for example, a passive system.

In this embodiment, a pulsar ring 60 having a detected portion 61 is arranged within the hat portion 52 of the brake disc 5 and attached to the brake disc 5 . The pulsar ring 60 is made of, for example, a magnetic material (thin steel plate).

The pulsar ring 60 is formed of a plate-like member orthogonal to the axis O, and is attached to the inner surface of the bottom wall portion 53 of the hat portion 52 so as to come into surface contact therewith. The outer diameter of the pulsar ring 60 is at least greater than the maximum outer diameter of the inner ring flange 12f. The outer diameter of the pulsar ring 60 is larger than the maximum outer diameter of the outer ring flange 13f, but may be smaller.

The pulsar ring 60 includes an annular portion centered on the axis O and a mounting portion 64 protruding radially inward from the inner peripheral edge of the annular portion. The detected portion 61 is provided on a surface of the annular portion facing inward in the vehicle width direction. The detected portion 61 is formed by unevenness repeatedly provided in the circumferential direction.

A plurality of attachment portions 64 are provided, for example, at intervals in the circumferential direction. A through hole is provided in the mounting portion 64, and the pulsar ring 60 is fixed to the bottom wall portion 53 of the hat portion 52 by a screw member 71 passed through the through hole. A screw member is a type of fastening member. Fastening members include screws, bolts, and screws.

Alignment of the pulser ring 60 is performed using a jig. Since the central cylindrical portion of the bottom wall portion 53 of the hat portion 52 of the brake disc 5 is fitted to the inner ring 12 as the wheel hub, whirling of the pulser ring 60 fixed to the bottom wall portion 53 is prevented.

The rotation sensor 62 is attached to the outer ring 13 which is a fixed portion of the wheel hub bearing portion 11 so as to face the detected portion 61 of the pulsar ring 60 . Rotation sensor 62 is composed of, for example, a pickup coil.

Specifically, the rotation sensor 62 is attached to the outer ring flange 13 f via a flat plate-like holding member 63 . The holding member 63 is fixed in contact with one end surface of the outer ring flange 13f in the direction of the axis O (the surface facing outward in the vehicle width direction). The end face of the outer ring flange 13f is orthogonal to the axis O and arranged parallel to the pulsar ring 60 . Therefore, the holding member 63 and the pulser ring 60 are arranged in parallel.

The holding member 63 is provided with a plurality of through holes 63a and 63b. The through-holes 63a are holes for passing the screw members 72, and are provided, for example, two (a plurality of). The through hole 63b is a hole through which the rotation sensor 62 is passed. In the present embodiment, the rotation sensor 62 passed through the through hole 63b of the holding member 63 is previously fixed to the holding member 63 by integral molding, press fitting, or the like.

The holding member 63 is desirably attached to the recessed portion 13b of the outer ring flange 13f. In this case, the screw member 72 passed through the through hole 63a from one side in the direction of the axis O is screwed into the female screw hole 13c provided in the recessed portion 13b of the outer ring flange 13f. As shown in FIG. 2, the entire head of the screw member 72 is arranged outside the minimum outer diameter of the inner ring 12 when viewed from the direction of the axis O, and at least part of the head of the screw member 72 is It is arranged inside the maximum outer diameter of the inner ring 12 .

The holding member 63 has a portion 63p that protrudes radially outward beyond the recessed portion 13b of the outer ring flange 13f in the attached state, and the rotation sensor 62 is held at this portion 63p. The through hole 63b is provided at a position facing the detected portion 61 of the pulsar ring 60 in this portion 63p.

The rotation sensor 62 extends linearly from the front end to the rear end, and is held by a holding member 63 so that the front end faces outward in the vehicle width direction. Since the through-hole 63b of the holding member 63 extends parallel to the axis O, simply passing the rotation sensor 62 through the through-hole 63b allows the detection surface 62a, which is the tip surface of the rotation sensor 62, and the detected portion 61 of the pulser ring 60 to be connected. can be parallel.

As described above, according to the present embodiment, since the holding member 63 of the rotation sensor 62 is configured by a plane (flat thin plate) parallel to the detected portion 61, the detection surface 62a of the rotation sensor 62 and the detection target The interval (gap) between the portion 61 can be easily managed. Specifically, the axial dimension of the component interposed between the holding member 63 and the detected portion 61 (for example, the distance from the holding member 63 to the inner ring flange 12f, the distance from the holding member 63 to the detection surface 62a of the rotation sensor 62 ), gap adjustment between the detection surface 62a of the rotation sensor 62 and the detected portion 61 can be made unnecessary.

In addition to the axial dimensions of the parts interposed between the holding member 63 and the detected part 61, the axial dimensions of the pulsar ring 60 (detected part 61), the mating surfaces of the brake disc 5 and the pulsar ring 60 By further controlling runout, etc., the gap after the brake disc 5 is assembled to the inner ring flange 12f can be determined more accurately.

Further, since the holding member 63 of the rotation sensor 62 is configured by a plane parallel to the detected portion 61, even if the holding member 63 is displaced within the clearance of the through hole 63a through which the screw member 72 is inserted, Since the holding member 63 can only be displaced in the radial direction, the axial position of the rotation sensor 62 remains unchanged. Therefore, the gap management between the detection surface 62a of the rotation sensor 62 and the detected portion 61 can be facilitated.

Further, since the rotation sensor 62 is attached to the outer ring flange 13f arranged outside the casing 10 instead of the casing 10, the number of parts intervening from the attachment site to the detected portion 61 can be reduced. Thereby, it is possible to easily manage the gap between the detected portion 61 and the rotation sensor 62 , that is, manage the dimensions of the wheel speed detecting device 6 . In addition, it is possible to save labor for processing the casing 10 .

Furthermore, in the present embodiment, the holding member 63 is fixed to the recessed portion 13b of the outer ring flange 13f (that is, the portion located between the circumferentially adjacent projecting portions 13a), and the outer circumference of the outer ring flange 13f (the outer ring 13 , i.e., the circle passing through the outer diameter side edges of all the protrusions 13a) C1. As a result, the radial dimension of the wheel speed detection device 6 can be reduced, and the wheel speed detection device 6 can be arranged within the hat portion 52 of the brake disc 5 .

Although it is desirable that the entire through-hole 63b of the holding member 63 is located radially inward of the outer circumference C1 of the outer ring flange 13f, at least a portion of the through-hole 63b is located radially inward of the outer circumference C1. It should be inside.

Further, in the present embodiment, the rotation sensor 62 is attached via the holding member 63 from the outside in the vehicle width direction. Therefore, even if the rotation sensor 62 is arranged at a position overlapping the output gear 36 when viewed in the direction of the axis O (the radial positions of the rotation sensor 62 and the output gear 36 overlap), the wheel hub bearing portion 11 can be disassembled. The rotation sensor 62 can be easily replaced without having to do so.

(Modification 1)
In this embodiment, the rotation sensor 62 is fixed to the holding member 63. However, as shown in FIGS. . 3 and 4 are diagrams schematically showing a wheel speed detection device 6A in this modified example.

A portion 63p of the holding member 163 is provided with a through hole 63b for fitting the body portion of the rotation sensor 162, and a through hole 63c through which the screw member 73 passing through the fixed piece 62b of the rotation sensor 162 is passed. ing.

The inner wall of the through-hole 63c is threaded with a female thread (not shown), and the screw member 73 is passed through the through-hole 63c from the inside in the vehicle width direction. The screw member 73 is screwed into the through hole 63c with the fixed piece 62b of the rotation sensor 162 sandwiched between the head and the holding member 163. As shown in FIG.

According to this modification, it is possible to attach and detach the rotation sensor 162 from the outside in the vehicle width direction by using the rotation sensor 162 that is inserted into the stay (holding member) from the inside in the vehicle width direction. As a result, it is possible to use a general-purpose rotation sensor 162 that is inserted from the inner side in the vehicle width direction, so it is possible to share parts and reduce costs.

(Modification 2)
In this embodiment, the holding member 63 that holds the rotation sensor 62 is fixed to the outer ring flange 13f, but as shown in FIGS. The holding member 63 may be fixed to the hub support member 16 when the hub support member 16 is fixed to the casing . 5 and 6 are diagrams schematically showing the mounting structure of the wheel hub bearing portion 11A and the rotation sensor in this modified example. Although the hub support member 16 corresponds to a hub attachment (intermediate member) arranged between the outer ring 113 and the casing 10, the hub support member 16 is assumed to be a component of the outer ring 113 in this modified example. .

The outer diameter (maximum outer diameter) of the outer ring flange 113f is smaller than the outer diameter (maximum outer diameter) of the outer ring flange 13f of the first embodiment, and substantially the same as the outer diameter (maximum outer diameter) of the inner ring flange 12f. The outer diameter (maximum outer diameter) of the hub support member 16 is larger than the outer diameter of the outer ring flange 113f.

The outer ring flange 113f is fixed only to the hub support member 16 by bolts 84 passed from one side in the direction of the axis O, and the hub support member 16 is fixed to the casing 10 by bolts 85 passed from one side in the direction of the axis O. there is The head of the bolt 85 is arranged radially outside the head of the bolt 84 .

The shape of the hub support member 16 is star-shaped like the outer ring flange 13f, and includes a plurality of protrusions 16a and a plurality of recesses 16b. The projecting portion 16a of the hub support member 16 and the projecting portion 13a of the outer ring flange 113f are aligned with the axis O as the center.

In this case, the holding member 63 that holds the rotation sensor 62 is fixed to the recessed portion 16b of the hub support member 16, and is located on the outer circumference of the hub support member 16 (the circle with the maximum outer diameter of the hub support member 16, i.e., It is desirable that the center be arranged radially inward of a circle C2 passing through the radially outer edges of all the projecting portions 16a. As a result, it is possible to reduce the radial dimension of the wheel speed detection device 6 also in this modification.

(Modification 3)
In the present embodiment, the rotation sensor 62 is positioned by fixing the holding member 63 to the outer ring flange 13f with a plurality of (for example, two) screw members 72; , the holding member 263 may be fixed to the outer ring flange 213f by one screw member 72. As shown in FIG. 7 and 8 are diagrams schematically showing a wheel speed detection device 6B in this modification.

The outer ring flange 213f has a fitting portion 13p for positioning the rotation sensor 62, which is connected to one of the plurality of recessed portions 13b. The fitting portion 13p protrudes radially outward from the circumferential central portion of one recessed portion 13b. A fitting hole 13q penetrating along the axis O is provided in the fitting portion 13p.

The through hole 63b of the holding member 263 overlaps with the fitting hole 13q, and the rotation sensor 62 is passed through the fitting hole 13q of the fitting portion 13p and the through hole 63b of the holding member 263. As shown in FIG. As a result, even if the holding member 263 is fixed to the outer ring flange 213f at one position, the rotation sensor 62 can be positioned. Therefore, since the planar area of the holding member 253 can be made smaller than that in the first embodiment, the degree of freedom in arranging the rotation sensor 62 can be improved.

In addition, in this modification, as shown in FIG. 9, it is desirable to provide a notch 13r in the fitting portion 13p of the outer ring flange 213f. The notch 13r is linearly provided radially outward from the fitting hole 13q. As a result, even when the cable 62c of the rotation sensor 62 is arranged on the inner side in the vehicle width direction, the cable 62c can be passed through the notch 13r. It can be done from the outside.

(Other modifications)
In this embodiment, the pulsar ring 60 having the detected portion 61 is attached to the bottom wall portion 53 of the hat portion 52 of the brake disc 5. It is not limited to such attachment example as long as it is arranged facing inward. For example, the bottom wall portion 53 itself of the hat portion 52 may be provided with unevenness as a portion to be detected.

<Embodiment 2>
In the first embodiment, the detected portion 61 of the pulsar ring 60 and the holding member 63 holding the rotation sensor 62 are arranged so as to be perpendicular to the axis O, but in the present embodiment, These are arranged obliquely with respect to the axis O.

A mounting structure of the wheel speed detection device 6C according to the present embodiment will be described with reference to FIGS. 10 to 12. FIG. FIG. 10 is a cross-sectional view schematically showing the wheel speed detection device 6C. 11 and 12 are perspective views of the brake disc 5 to which the pulsar ring 60A is attached, showing views of the brake disc 5 viewed from outside and inside in the vehicle width direction, respectively.

The wheel speed detection device 6C includes a pulser ring 60A, a rotation sensor 62, and a holding member 65 that holds the rotation sensor 62. As shown in FIG. The wheel hub bearing portion in the present embodiment has the same configuration as the wheel hub bearing portion 11A in Modification 2 of Embodiment 1, and the outer ring flange 113f is fixed to the casing 10 via the hub support member 16. and

The pulsar ring 60A has a detected portion 61 and a flange portion 64A. The pulsar ring 60A is fixed to the bottom wall portion 53 of the hat portion 52 of the brake disc 5 at the flange portion 64A. The detected portion 61 extends in the axle direction from the radially inner edge of the flange portion 64A and is formed in a conical shape so that the diameter becomes smaller inward in the vehicle width direction.

A bolt 74 is fixed in advance to the bottom wall portion 53 of the hat portion 52 of the brake disc 5, and a through hole for inserting the bolt 74 is provided in the flange portion 64A. The flange portion 64A is attached to the bottom wall portion 53 of the hat portion 52 by a nut 75 screwed onto the tip portion of the bolt 74. As shown in FIG. A countersunk screw may be interposed between the flange portion 64A and the nut 75. As shown in FIG. The flange portion 64A may be configured in a ring shape as shown in FIGS. 11 and 12, or may be provided in plural at equal intervals along the circumferential direction.

Also in this form, the alignment of the pulsar ring 60A is performed using a jig. Since the center cylindrical portion 50 of the bottom wall portion 53 of the brake disc 5 is fitted to the inner ring 12 as the wheel hub, whirling of the pulser ring 60A fixed to the bottom wall portion 53 is prevented. 11 and 12 show a through hole 53a provided in the bottom wall portion 53 of the brake disc 5, for inserting the wheel bolt 82. As shown in FIG.

As in the first embodiment, the holding member 65 is fixed to one end surface of the hub support member 16 in the direction of the axis O by a screw member 72 from the outside in the vehicle width direction. The holding member 65 includes a radially extending mounting portion 651 and a holding portion 652 obliquely extending outward in the vehicle width direction from a radially outer edge of the mounting portion 651 . The holding portion 652 is inclined so that the angle with the mounting portion 651 is an obtuse angle.

The mounting portion 651 is provided with a through-hole 65a through which the screw member 72 is passed, and the holding portion 652 is provided with a through-hole 65b through which the rotation sensor 62 is passed. The holding portion 652 may further be provided with a female screw hole 65c into which the screw member 73 for fastening the fixed piece 62b of the rotation sensor 62 is screwed.

The angle formed between the attachment portion 651 and the holding portion 652 of the holding member 65 is substantially the same as the angle formed between the flange portion 64A of the pulsar ring 60A and the detection target portion 61 . That is, the holding portion 652 of the holding member 65 constitutes a planar portion parallel to the detected portion 61 . As a result, the detection surface 62a of the rotation sensor 62 can be arranged parallel to the detected portion 61 simply by passing the rotation sensor 62 straight through the through hole 65b provided in the holding portion 652 of the holding member 65. .

According to the present embodiment, since the holding portion 652 that holds the rotation sensor 62 is arranged obliquely with respect to the axis O, the radial distance from the rotation sensor 62 to the brake disc 5 is greater than in the first embodiment. can take long. As a result, it is possible to suppress the thermal influence of the brake disc 5 which generates heat during braking, so that the detection accuracy of the wheel speed by the rotation sensor 62 can be improved.

Further, according to the present embodiment, at least part of the rotation sensor 62 can be arranged inside the output gear 36, so the diameter of the pulsar ring 60 can be reduced. As a result, the vibration of the pulsar ring 60 can be suppressed, so that the wheel speed detection accuracy can be improved.

When the rotation sensor 62 is attached to the hub support member 16 as in this embodiment, the attachment portion of the holding member 65 may be integrated with the hub support member 16 . As a result, the number of parts can be reduced, and the cost and the number of assembling man-hours can be reduced.

As for the material of the casing 10, an aluminum alloy is generally used in order to reduce the weight. Less is. Therefore, by attaching the rotation sensor 62 to the hub support member 16, the influence on the rotation sensor 62 can be suppressed.

Also in this embodiment, the rotation sensor 62 may be attached to the outer ring flange.

<Other embodiments>
In each of the above embodiments, the wheel speed detection device employing the passive method has been described, but an active method may be employed. In that case, for example, a known magnetic encoder can be employed as the detected portion of the pulsar ring. A magnetic encoder is an annular magnet in which N poles and S poles are repeatedly arranged in the circumferential direction. In this case, the rotation sensor 62 reads the intensity of magnetism accompanying the rotation of the magnetic encoder.

Also, in the above description, a brake disc is shown as a disc-type brake rotor, but a drum-type brake rotor may be used. Further, although the example in which the speed reduction section 31 is a parallel three-shaft gear speed reducer having the axes O, N, and M extending parallel to each other has been shown, the configuration of the speed reduction section 31 is not limited, and for example, a planetary gear type speed reducer It may be applied to a machine or a cycloidal reducer.

Also, the above embodiments and modifications may be combined.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the meaning and range of equivalents of the scope of the claims.

1 in-wheel motor drive device 5 brake disc 6, 6A, 6B, 6C wheel speed detector 10 casing 11, 11A wheel hub bearing portion 12 inner ring 13, 113 outer ring 13f, 113f, 213f outer ring flange, 14 rolling element, 15 output shaft, 16 hub support member, 20 motor housing, 21 motor section, 30 reduction gear housing, 31 reduction section, 32 input gear, 32s input shaft, 33, 35 intermediate gear, 34 intermediate shaft, 36 output gear 51 rotor portion 52 hat portion 53 bottom wall portion 54 annular step (outer peripheral portion) 60, 60A pulsar ring 61 detected portion 62, 162 rotation sensor 63, 65, 163, 253, 263 holding Member, W wheel wheel.

Claims (3)

A wheel hub bearing portion including an inner ring that is coaxially coupled to a brake rotor having a hat portion that is recessed outward in the vehicle width direction and that rotates integrally with the brake rotor, and an outer ring that is non-rotatably fixed. An in-wheel motor drive device comprising:
a detected portion arranged in the hat portion of the brake rotor so as to be orthogonal to the axis of the wheel hub bearing portion and generating a magnetic flux change in a circumferential direction; and the wheel hub bearing facing the detected portion. a wheel speed detection device including a rotation sensor attached to the outer ring of the part or a hub support member that supports the outer ring ;
The wheel speed detection device further includes a holding member for attaching the rotation sensor to the flange portion of the outer ring or the hub support member,
at least part of the holding member is arranged radially inward of the flange portion of the outer ring or the outer circumference of the hub support member;
An in-wheel motor drive device , wherein a fitting hole for fitting the rotation sensor is provided in the flange portion of the outer ring or the hub support member . The holding member has a planar portion parallel to the detected portion,
2. The in-wheel motor drive device according to claim 1 , wherein said rotation sensor is fixed to said planar portion of said holding member. The in-wheel motor drive device according to claim 1 or 2 , wherein the holding member is fixed to the flange portion of the outer ring or the hub support member by a fastening member passed from the outside in the vehicle width direction.

Images