JP2011162034A - In-wheel motor driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in-wheel motor driving device capable of avoiding any deformation of a drive motor even when connecting the in-wheel motor driving device to a suspension member such as a trailing arm. <P>SOLUTION: The in-wheel motor driving device 21 has a flange part 22e arranged between a motor section A and a speed reduction section B and expanded in the radial direction. The flange part 22e has connection sections 61, 62 for connecting the in-wheel motor driving device 21 to a vehicle body side member. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an in-wheel motor drive device that drives a wheel, and more particularly, to an attachment structure with a suspension member such as a trailing arm, a lower arm, or a shock absorber.

  2. Description of the Related Art In recent years, in-wheel motor drive devices that drive wheels by being partly or wholly arranged in the inner space of a wheel road wheel have attracted attention in the technical field of vehicles. A conventional in-wheel motor drive device is described in, for example, Japanese Patent Application Laid-Open No. 2008-44537 (Patent Document 1). An in-wheel motor drive device described in Patent Document 1 includes a drive motor, a speed reducer that receives a driving force from the drive motor, decelerates the number of rotations, and outputs it to the wheel side, and an output shaft of the speed reducer The hub member of the wheel to be coupled is arranged coaxially and in series. This speed reducer is a cycloid speed reduction mechanism, and a high speed reduction ratio can be obtained as compared with a planetary gear speed reduction mechanism that is general as a conventional speed reducer. Therefore, the required torque of the drive motor can be reduced, which is advantageous in that the size and weight of the in-wheel motor drive device can be reduced.

JP 2008-44537 A

  By the way, since it is necessary to attach a wheel to a vehicle body, the in-wheel motor drive device couple | bonded with a wheel couple | bonds with a vehicle body side member. Specifically, in order to suspend the wheel on the vehicle body by the suspension device, an in-wheel motor drive device coupled to the wheel is coupled to the suspension member of the suspension device. Thereby, the wheel is suspended from the vehicle body. Wheel suspension methods include the torsion beam method, semi-trailing arm method, full trailing arm method, strut method, double wishbone method, etc., depending on the selected suspension method, torsion beam, trailing arm, lower arm, An in-wheel motor drive device is coupled to a suspension member such as an upper arm or a shock absorber.

  The suspension member strokes in the vertical direction due to the wheel load applied to the tire, such as the weight of the vehicle itself, disturbance from the road surface during traveling, and moment load during turning. At this time, the suspension member and the in-wheel drive device are deformed, but there is a concern that the deformation may adversely affect the members inside the in-wheel drive device.

  Specifically, the trailing arm is described as an example. In order to realize the running stability of the vehicle equipped with such an in-wheel motor drive device, the trailing end of the trailing arm is connected to the base end of the trailing arm. And an in-wheel motor drive device provided on each wheel. Specifically, in the in-wheel motor drive device, a portion protruding from the inner space region of the road wheel or a portion in the inner space region near the opening of the inner space region and the free end of the trailing arm Join. That is, the drive motor portion and the cycloid reducer portion of the in-wheel motor drive device are generally attached to the rear end portion of the trailing arm extending in the vehicle front-rear direction so as to support the entire in-wheel motor drive device as much as possible. It is.

  However, in the mounting structure as described above, deformation occurs in the trailing arm and the entire in-wheel drive device connected thereto due to the wheel load input from the wheel to the hub member. For this reason, the reduction gear and the drive motor are also deformed inside the drive device. The drive motor is supported in both ends of the motor casing by bearings provided at both end faces of the motor casing, and the rotor that rotates at high speed and the stator that is fixed to the casing face each other through a slight radial gap. It is easily affected by the deformation of the apparatus, and the problem that the rotor comes into contact with the stator is likely to occur. In order to solve this problem, it is conceivable to increase the rigidity by making the motor casing steel or making it thick.

  On the other hand, in order to further improve running stability, there is a need to reduce the weight of the lower structure including the in-wheel motor drive device disposed on the road surface side than the suspension device. As a means for reducing the weight of the in-wheel drive device itself, it is possible to reduce the thickness of the casing member.

  In view of the above situation, the present invention is a case where the in-wheel motor drive device is connected to a vehicle body side member such as a suspension member under the demand for thinning and weight reduction of the in-wheel motor drive device. An object of the present invention is to provide an in-wheel motor drive device that can avoid deformation of the drive motor.

  For this purpose, the in-wheel motor drive device according to the present invention includes a motor unit, a speed reduction unit arranged on one side of the motor unit in the axial direction to decelerate and output the rotation of the motor unit, and further on one side of the speed reduction unit in the axial direction. An in-wheel motor drive device comprising: a wheel hub that has a wheel hub that is disposed and that transmits a reduced rotation output from the speed reduction unit to the wheel side; and a wheel hub bearing that rotatably supports the wheel hub, A flange-like member disposed between the motor portion and the speed reduction portion and extending in the radial direction is provided, and the flange-like member has a connecting portion for connecting the in-wheel motor drive device to the vehicle body side member.

  According to the present invention, since the flange-like member disposed between the motor portion and the speed reduction portion has the connection portion for connecting to the vehicle body side member, the wheel load is reduced to the wheel hub bearing portion and the speed reduction portion. Through the part and the flange-like member, not through the motor part. Therefore, the wheel load is not input to the motor unit, the motor unit is not deformed, and the rotor and the stator can be prevented from contacting each other inside the motor. The flange-like member of the present invention may be any member that extends in the direction perpendicular to the axis line, such as an inward flange or an outward flange. In addition to connecting the motor part and the reduction part having different outer diameters, these motor part and It should be understood to include an outward flange projecting outward from the speed reduction portion.

  Further, when the vehicle body side member is a deformable trailing arm, the deformation of the trailing arm is not input to the in-wheel motor drive device by increasing the rigidity of the flange-like member of the present invention. Therefore, the present invention contributes to the reduction in thickness and weight of the in-wheel motor drive device.

  If the connecting part of the present invention is a pivotable ball joint, a seat part that is tightly fixed, or a part that is connected to a vehicle body side member that is attached to the vehicle body side, its application range is limited. Not. The connecting portion of the present invention is attached to the vehicle body side and connected to a suspension member that suspends the wheel and the in-wheel motor driving device, so that external force from the road surface and shock during acceleration / deceleration are input to the in-wheel motor driving device. Even if it is done, a deformation | transformation of a motor part can be prevented. Further, the structure of the motor unit may be a radial gap or an axial gap, and is not particularly limited. The structure of the speed reduction unit may be a planetary gear mechanism or a cycloid speed reduction mechanism, and is not particularly limited.

  The flange-shaped member of the present invention is not particularly limited as long as it is disposed between the motor unit and the speed reduction unit. Preferably, the motor unit includes a motor unit casing that forms an outer shell of the motor unit, and the speed reducing unit forms an outer shell of the speed reducing unit and is coupled to an outer ring of the wheel hub bearing while being axially located. Part casing. The flange-shaped member is fixed to both the motor part casing and the speed reduction part casing. According to this embodiment, the wheel load can be suitably supported by the casing of the in-wheel motor drive device. The flange-like member of the present invention is a member separate from the motor unit casing and the speed reduction unit casing, and is fixed by bolts or the like, or when integrally coupled to at least one of the motor unit casing or the speed reduction unit casing Should be understood to include

  The vehicle body side member of the present invention generally assumes a suspension member of a suspension device. The connecting portion can be connected to any suspension member, and is disposed on the front side of the axis or on the rear side of the axis. Or it arrange | positions above an axis line, or arrange | positions below an axis line. For example, as an embodiment applicable to a trailing arm that extends in the vehicle front-rear direction as a suspension member, the connecting portion is disposed on the front side of the axis and protrudes downward, and is disposed on the rear side of the axis. And a rear connecting portion protruding downward. According to this embodiment, since the connecting portions are respectively arranged on the front and rear of the axis and project downward, the trailing arm can support the in-wheel motor drive device from below. Therefore, the present invention can be applied to a suspension device including a trailing arm.

  Alternatively, as an embodiment applicable to a strut suspension device including a strut and a lower arm as a suspension member, the connecting portion includes an upper connecting portion disposed above the axis and a lower portion disposed below the axis. Side connection part. According to this embodiment, the upper connecting portion is connected to the lower end of the strut, and the lower connecting portion is connected to the free end of the lower arm, so that it can be applied to the strut suspension device. Further, according to the embodiment, the upper connecting portion is connected to the free end of the upper arm, and the lower connecting portion is connected to the free end of the lower arm, so that it can be applied to a double wishbone suspension device.

  According to the present invention, the flange-shaped member is responsible for the wheel load, but the motor portion may be responsible for a part of the wheel load to such an extent that the motor portion is not deformed. For example, the motor unit further includes a motor side connecting part for connecting to the vehicle body side shock absorber at the motor end located on the other axial direction opposite to the speed reducing part. According to this embodiment, the freedom degree of a suspension apparatus becomes large and an in-wheel motor drive device can be suspended with various suspension apparatuses.

  Specifically, the connecting portion is disposed below the axis, and the motor portion is connected to the vehicle body side member at the upper portion of the motor end located on the other axial direction opposite to the speed reducing portion. It further has a connection part. Alternatively, the connecting portion is disposed above the axis, and the motor portion further includes a motor side connecting portion for connecting to the vehicle body side member at a lower portion of the motor end located on the other axial direction opposite to the speed reducing portion. Have.

  Preferably, the flange-like member has a caliper connecting portion for attaching and fixing the brake caliper. According to this embodiment, it becomes possible to attach and fix a brake caliper to the flange-like member, which can contribute to the layout of the brake caliper.

  Preferably, the speed reduction unit includes an input shaft coupled and fixed to the rotation shaft of the motor unit, a disc-shaped eccentric member that is eccentrically coupled to an end of the input shaft from the rotation axis of the input shaft, and an inner periphery that is an eccentric member. A revolving member that is attached to the outer periphery of the shaft so as to be relatively rotatable, and that performs a revolving motion around the rotation axis along with the rotation of the input shaft, and an outer periphery that engages with the outer peripheral portion of the revolving member to cause the revolving motion of the revolving member. It is a cycloid reduction mechanism having an engaging member and a motion conversion mechanism that takes out only the rotation of the revolution member and transmits it to the wheel hub. According to the embodiment having such a cycloid reduction mechanism, a very large reduction ratio can be obtained.

  The motion conversion mechanism is not limited to one embodiment, but the revolution member has a plurality of holes formed at equal intervals in the circumferential direction around the rotation axis, an output shaft coupled to the wheel hub, and an output shaft. And a plurality of inner engaging members which are provided at equal intervals in the circumferential direction around the axis of the output shaft and respectively engage with the holes.

  Alternatively, as another embodiment, the motion conversion mechanism includes an output shaft coupled to the wheel hub, a plurality of holes formed at equal intervals in the circumferential direction around the axis of the output shaft at the end of the output shaft, and a revolving member And a plurality of inner engaging members which are provided at equal intervals in the circumferential direction around the rotation axis and engage with the holes, respectively.

  As described above, the present invention includes a flange-shaped member that is disposed between the motor portion and the speed reduction portion and extends in the radial direction, and the flange-shaped member is used for connecting the in-wheel motor drive device to the vehicle body side member. It has a connecting part. Thereby, a wheel load is not input into a motor part, and a deformation | transformation of a motor part can be prevented suitably. Further, the deformation of the trailing arm is not input to the motor unit and the speed reduction unit. Furthermore, the motor part can be reduced in weight by using a thin member for the motor part casing. As a result, the unsprung weight of the suspension device can be reduced and the riding comfort performance of the vehicle can be improved.

It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes 1st Example of this invention. It is a cross-sectional view which shows the deceleration part of the Example. It is a front view of the same Example. It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes 2nd Example of this invention. It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes 3rd Example of this invention. It is a perspective view which shows typically the state suspended on the suspension apparatus by the Example. It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes 4th Example of this invention. It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes 5th Example of this invention. It is a perspective view which shows typically the state suspended on the suspension apparatus by the Example.

  Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings. FIG. 1 is a longitudinal sectional view showing an in-wheel motor drive apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a speed reduction portion of the same embodiment. FIG. 3 is a longitudinal sectional view showing a state in which the embodiment is viewed from one side in the axial direction.

  An in-wheel motor drive device 21 that is disposed in the space area in the road wheel of the wheel and drives the wheel includes a motor unit A that generates a driving force, and a deceleration unit B that decelerates and outputs the rotation of the motor unit A. And a wheel hub bearing portion C for transmitting the output from the deceleration portion B to a wheel (not shown). And the motor part A, the deceleration part B, and the wheel hub bearing part C are arranged in series and coaxially in this order. The in-wheel motor drive device 21 is mounted in, for example, a wheel housing of an electric vehicle or a hybrid drive vehicle.

  The motor unit A includes a motor unit casing 22a that forms an outer shell, a stator 23 that is fixed to the motor unit casing 22a, and a rotor 24 that is disposed at a position facing the inner side of the stator 23 via a gap that is radially open. And a radial gap motor having a motor rotating shaft 35 that is fixedly connected to the inside of the rotor 24 and rotates integrally with the rotor 24.

  The motor section casing 22a has a cylindrical shape and is coupled to the other end of the speed reduction section casing 22b on one side in the axis O direction (left side in FIG. 1). The inner periphery of the motor casing 22a supports the stator 23. An inward flange-shaped flange portion 22e extending in the radial direction is formed on one side of the motor portion casing 22a in the axis O direction. In this embodiment, the flange portion 22e is coupled to the motor portion casing 22a. However, the flange portion 22e may be a separate member from the motor portion casing 22a, and may be fixed by a bolt or the like. The flange portion 22e is fixed to the other end of the speed reduction portion casing 22b by a bolt.

  The flange portion 22e extending in the radial direction is disposed between the motor portion casing 22a and the speed reduction portion casing 22b, and the motor portion casing 22a having a relatively large outer diameter and the speed reduction portion casing 22b having a relatively small outer diameter. Connect. The inner periphery of the inward flange 22e rotatably supports one end portion of the motor rotating shaft 35 via a rolling bearing 36b. A disk-shaped motor cover 22v is fixed to the other side in the axis O direction of the motor unit casing 22a. The center portion of the motor cover 22v rotatably supports the other end portion of the motor rotating shaft 35 via the rolling bearing 36a.

  The speed reduction part B has a speed reduction part casing 22b that forms an outer shell and an output shaft 28 that outputs the motor rotation shaft 35 by reducing the rotation thereof, and is arranged on one side of the motor part A in the axis O direction. Specifically, the deceleration unit B is a cycloid deceleration mechanism. The input shaft 25 of the deceleration unit B extends along the axis O, protrudes toward the motor unit A, and the protruding end is connected and fixed to one end in the axial direction of the motor rotating shaft 35. Since the motor rotation shaft 35 of the motor part A and the input shaft 25 of the speed reduction part B rotate integrally, they are also referred to as motor-side rotation members. One end of the input shaft 25 located on the side opposite to the motor part A is supported in the speed reduction part B by a rolling bearing 36c.

  Two disc-shaped eccentric members 25 a and 25 b are fixed to the outer periphery of the input shaft 25. Although the motor rotation shaft 35 and the input shaft 25 extend to coincide with the rotation axis O of the in-wheel motor drive device 21, the centers of the eccentric members 25 a and 25 b do not coincide with the axis O. Further, the two eccentric members 25a and 25b are provided with a 180 ° phase shift so as to cancel out vibrations generated by the centrifugal force due to the eccentric motion.

  Curve plates 26a and 26b as revolving members are rotatably held on the outer circumferences of the eccentric members 25a and 25b, respectively. A plurality of outer pins 27 as outer peripheral engaging members are engaged with the outer peripheral portions of the curved plates 26a and 26b which are bent in a wave shape. The outer pin 27 is attached to the inner periphery of the speed reducer casing 22b. A center collar 29 for preventing the inclination of the curved plates 26a and 26b is provided in the gap between the curved plates 26a and 26b.

  The speed reduction unit casing 22b has a cylindrical shape with a smaller diameter than the motor unit casing 22a, and is coupled to one end side of the motor unit casing 22a on the other side in the axis O direction (right side in FIG. 1), and one in the axis O direction (FIG. 1). To the other end side of the wheel hub bearing outer ring 22c. The casings 22 a and 22 b and the outer ring 22 c constitute one casing 22. The casing 22 rotatably supports a rotating element inside the casing 22 through various bearings such as the above-described rolling bearing 36a and a wheel hub bearing 33 described later. Therefore, the inner periphery of the speed reduction part casing 22b is separated from rotating elements such as curved plates 26a and 26b described later, and does not contact the rotating elements.

  The output shaft 28 of the speed reduction part B coincides with the rotation axis O and protrudes from the speed reduction part B in the direction of the axis O to the wheel hub bearing part C, and has a flange part 28a and a shaft part 28b. Holes for fixing the inner pins 31 are formed on the end face of the flange portion 28 a arranged in the speed reduction portion B at equal intervals on the circumference around the rotation axis O of the output shaft 28. A wheel hub 32 is connected and fixed to the outer peripheral surface of the shaft portion 28b disposed in the wheel hub bearing portion C. Since the output shaft 28 of the deceleration part B and the wheel hub 32 of the wheel hub bearing part C rotate together, they are also referred to as wheel-side rotating members. The inner pin 31 implanted in the flange portion 28a projects toward the other side in the axis O direction, and the tip end portion engages with the radial center region of the curved plates 26a and 26b. The center hole 28c of the flange portion 28a receives one end portion of the input shaft 25 and supports one end of the input shaft 25 via the rolling bearing 36c so as to be relatively rotatable.

  Referring to FIG. 2, the curved plate 26 a has a plurality of corrugations composed of trochoidal curves such as epitrochoids on the outer peripheral portion, and a plurality of through holes 30 a and 30 b penetrating from one end face to the other end face. Have A plurality of through holes 30a are provided at equal intervals on the circumference centered on the center (rotation axis) of the curved plate 26b, and the radial center between the outer peripheral edge and the inner peripheral edge of the curved plate 26b. It is formed in a region and receives an inner pin 31 described later. Moreover, the through-hole 30b is provided in the center (rotation axis) of the curved plate 26b, and becomes an inner periphery of the curved plate 26b. The curved plate 26a is attached to the outer periphery of the eccentric member 25a so as to be relatively rotatable.

  That is, the curved plate 26a is supported by the rolling bearing 41 so as to be rotatable with respect to the eccentric member 25a. The rolling bearing 41 is formed directly on the inner peripheral surface of the inner ring member 42 having the inner peripheral surface fitted to the outer peripheral surface of the eccentric member 25a and having the inner raceway surface 42a on the outer peripheral surface, and the through hole 30b of the curved plate 26a. An outer raceway surface 43, a plurality of cylindrical rollers 44 disposed between the inner raceway surface 42a and the outer raceway surface 43, and a retainer (not shown) that holds the interval between the cylindrical rollers 44 adjacent in the circumferential direction. It is a cylindrical roller bearing provided. Alternatively, it may be a deep groove ball bearing. The inner ring member 42 further includes a pair of flange portions facing each other with the inner raceway surface 42a of the inner ring member 42 on which the cylindrical rollers 44 roll in the axial direction, and holds the cylindrical rollers 44 between the pair of flange portions. . The same applies to the curved plate 26b.

  The outer pins 27 are provided at equal intervals on a circumferential track centering on the rotation axis O of the input shaft 25. The outer pin 27 extends parallel to the axis O, and both ends thereof are held by an outer pin holding portion 45 that is fitted and fixed to the inner wall surface of the speed reduction portion casing 22 b that houses the speed reduction portion B of the casing 22. . More specifically, both end portions of the outer pin 27 in the axis O direction are rotatably supported by needle roller bearings 27a attached to the outer pin holding portion 45.

  When the curved plates 26a and 26b revolve around the rotation axis O of the input shaft 25, the curved waveform and the outer pin 27 engage with each other, causing the curved plates 26a and 26b to rotate. Further, the needle roller bearings 27a provided at both ends of the outer pin 27 reduce the frictional resistance with the curved plates 26a and 26b when the outer pin 27 comes into contact with the outer peripheral surfaces of the curved plates 26a and 26b.

  The motion conversion mechanism includes a plurality of inner pins 31 as inner engagement members implanted in the flange portion 28a of the output shaft 28, and through holes 30a provided in the curved plates 26a and 26b. The inner pins 31 are provided at equal intervals on a circumferential track centering on the rotation axis of the output shaft 28, extend in parallel with the axis of the output shaft 28, and the proximal end of the inner pin 31 is fixed to the output shaft 28. Has been. A needle roller bearing 31 a made up of a hollow cylindrical body and needle rollers is provided on the outer periphery of the inner pin 31. The needle roller bearing 31a reduces the frictional resistance with the curved plates 26a and 26b when the inner pin 31 contacts the inner peripheral surface of the through hole 30a of the curved plates 26a and 26b.

  An inner pin reinforcing member 31b that reinforces the inner pin 31 is connected and fixed to the tip of the inner pin 31 by press fitting. The inner pin reinforcing member 31b is an annular flange portion 31c that connects the tips of the plurality of inner pins 31, and a cylindrical tube that is coupled to the inner diameter portion of the flange portion 31c and extends in the axial direction so as to be away from the inner pin 31. Part 31d. The inner pin reinforcing member 31 b that reinforces the plurality of inner pins 31 uniformly distributes the load applied to some of the inner pins 31 from the curved plates 26 a and 26 b to all the inner pins 31.

  The inner pin 31 passes through a through hole 30a provided in a radial direction portion between the outer peripheral portion of the curved plates 26a and 26b and the axis of the input shaft 25. The through hole 30 a is provided at a position corresponding to each of the plurality of inner pins 31. The inner diameter dimension of the through hole 30a is set to be larger than the outer diameter dimension of the inner pin 31 (referred to as “maximum outer diameter including the needle roller bearing 31a”; the same applies hereinafter). Therefore, the inner pins 31 extending through the through holes 30a provided in the curved plates 26a and 26b become inner engagement members that respectively engage with the through holes 30a.

  The cylindrical portion 31d drives and couples the lubricating oil pump 51. When the plurality of inner pins 31 rotate together with the output shaft 28, the cylindrical portion 31 d that is rotated by the inner pins 31 drives the lubricating oil pump 51. The lubricating oil pump 51 provided inside the casing 22 is driven by the output of the motor unit A, and circulates lubricating oil inside the in-wheel motor driving device 21.

  The wheel hub bearing portion C includes a wheel hub 32 fixedly connected to the output shaft 28, a wheel hub bearing outer ring that rotatably supports the wheel hub 32, and a wheel hub 32 that is rotatable with respect to the wheel hub bearing outer ring 22c. And a wheel hub bearing 33 for holding. Further, the wheel hub bearing portion C is disposed further on one side in the axial direction of the speed reduction portion B. Thereby, the motor part A, the speed reduction part B, and the wheel hub bearing part C are sequentially arranged coaxially and in series along the axis O.

  The wheel hub bearing 33 is a double-row angular ball bearing, and the inner raceway surface is formed on the outer peripheral surface of the wheel hub 32. The outer raceway surface of the wheel hub bearing 33 is formed on the inner peripheral surface of the substantially cylindrical wheel hub bearing outer ring 22 c in the casing 22. The wheel hub 32 includes a cylindrical hollow portion 32 a that is coupled to one end of the output shaft 28, and a flange portion 32 b that is formed at an end portion on the side farther from the speed reduction portion B. A load wheel of a wheel (not shown) is fixedly connected to the flange portion 32b by a bolt 32c.

  Referring to FIG. 3, the flange portion 22 e has connecting portions 61 and 62 for connecting to the vehicle body side member. The connecting portion 61 integrally coupled to the flange portion 22e is located on the front side of the axis O, protrudes in the outer diameter direction from the motor portion casing 22a, and is directed downward. And the lower end surface 61u is formed in the front-end | tip. The connecting portion 62 that is integrally coupled to the flange portion 22e is located on the rear side of the axis O, protrudes in the outer diameter direction from the motor portion casing 22a, and is directed downward. And the lower end surface 62u is formed in the front-end | tip. The lower end surfaces 61u and 62u are located below the axis O, and form a common plane below the outer diameter of the motor section casing 22a.

  The connecting portions 61 and 62 are coupled to a suspension member as a vehicle body side member, and suspend the in-wheel motor device 21 together with a wheel (not shown) on the vehicle body. In the present embodiment, the flange portion 22e has a front connection portion 61 that is disposed on the front side of the axis and protrudes downward, and a rear connection portion 62 that is disposed on the rear side of the axis and protrudes downward. .

  According to such a present Example, the connection part 61 and the connection part 62 are spaced apart and arrange | positioned around the wheel hub 32, respectively. Thereby, the connection part 61 and the connection part 62 are suitably attached and fixed to the trailing arm of the suspension device extending in the front-rear direction. Specifically, the connecting portions 61 and 62 have bolt holes extending upward from the lower end surface, and are bolted in a state where the lower end surfaces 61u and 62u are in contact with a trailing arm (not shown).

  Thus, the flange part 22e has the connection parts 61 and 62 for connecting the in-wheel motor drive device 21 to a vehicle body side member. Therefore, the motor part A is cantilevered by the flange part 22e. Moreover, the deceleration part B and the wheel hub bearing part C are interposed between a wheel and a vehicle body side member.

  The wheel load that the wheel supporting the vehicle body receives from the vehicle body side via the connecting portions 61 and 62 is sequentially applied to the flange portion 22e, the speed reduction portion casing 22b, the outer ring 22c, the wheel hub bearing 33, and the wheel hub 32. Supported through. Thereby, no wheel load is input to the motor part A. Also, external force due to sudden acceleration / deceleration or road surface unevenness is not input to the motor unit A. Therefore, the deformation of the motor part A can be suitably prevented. Furthermore, the in-wheel motor drive device 21 can be reduced in weight by using a thin member for the motor portion casing 22a. As a result, the unsprung weight of the suspension device can be reduced and the riding comfort performance of the vehicle can be improved.

  Further, when the trailing arm elastically deforms following a change in wheel load, the rigidity of the flange portion 22e is increased so that the deformation of the trailing arm is not input to the in-wheel motor drive device 21.

  The operation principle of the in-wheel motor drive device 21 having the above configuration will be described in detail.

  The motor unit A receives, for example, an electromagnetic force generated by supplying an alternating current to the coil of the stator 23, and the rotor 24 composed of a permanent magnet or a magnetic material rotates.

  As a result, the motor rotation shaft 35 connected to the rotor 24 outputs rotation, and when the motor rotation shaft 35 and the input shaft 25 rotate, the curved plates 26a and 26b revolve around the rotation axis O of the input shaft 25. . At this time, the outer pin 27 is engaged so as to be in rolling contact with the curved waveform of the curved plates 26 a and 26 b to rotate the curved plates 26 a and 26 b in the direction opposite to the rotation of the input shaft 25.

  The inner pin 31 inserted through the through hole 30a is sufficiently thinner than the inner diameter of the through hole 30a, and comes into contact with the hole wall surface of the through hole 30a as the curved plates 26a and 26b rotate. As a result, the revolving motion of the curved plates 26 a and 26 b is not transmitted to the inner pin 31, and only the rotational motion of the curved plates 26 a and 26 b is transmitted to the wheel hub bearing portion C via the output shaft 28. Thus, the through hole 30a and the inner pin 31 serve as a motion conversion mechanism.

  Through this motion conversion mechanism, the output shaft 28 that is coaxially disposed so as to abut against the input shaft 25 takes out the rotation of the curved plates 26a and 26b as the output of the speed reduction unit B. As a result, the rotation of the input shaft 25 is decelerated by the deceleration unit B and transmitted to the output shaft 28. Therefore, even when the low torque, high rotation type motor unit A is employed, it is possible to transmit the necessary torque to the drive wheels.

Note that the reduction ratio of the speed reduction unit B having the above-described configuration is calculated as (Z _A −Z _B ) / Z _B where Z _{A is} the number of outer pins 27 and Z _B is the number of waveforms of the curved plates 26a and 26b. The In the embodiment shown in FIG. 2, because Z _A = 12 and Z _B = 11, the reduction ratio is 1/11, and a very large reduction ratio can be obtained.

  Thus, by adopting the cycloid reduction mechanism that can obtain a large reduction ratio without using a multistage configuration in the reduction part B, a compact and high reduction ratio in-wheel motor drive device 21 can be obtained.

  A second embodiment of the present invention will be described with reference to the longitudinal sectional view of FIG. About this 2nd Example, about the structure which is common in the Example mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted, and a different structure is demonstrated below. In 2nd Example, the flange part 22e has the connection parts 63 and 64 for connecting with a vehicle body side member. The connecting portion 63 that is integrally coupled to the flange portion 22e is located above the axis O, and protrudes in the outer diameter direction from the motor portion casing 22a. And the connection part 63a, 63b is formed in the front-end | tip part which protrudes upwards. The connecting portion 64 that is integrally coupled to the flange portion 22e is positioned below the axis O, and protrudes in the outer diameter direction from the motor portion casing 22a. And the connection part 64a is formed in the front-end | tip which protrudes below.

  These connecting portions 63a, 63b, and 64a are connected to a suspension member that is a vehicle body side member. The in-wheel motor drive device 21 of the embodiment shown in FIG. 4 is suitably attached to a strut suspension device. Specifically, the connecting portions 63a and 63b are connected to a lower end portion of a strut (not shown) extending in the vertical direction. The connecting portion 64a includes, for example, a ball joint and is connected to a free end of a lower arm (not shown) extending in the vehicle width direction. The lower arm may be a known lower arm having a vehicle width direction inner end as a base end and a vehicle width direction outer end as a free end.

  A third embodiment of the present invention will be described with reference to the longitudinal sectional view of FIG. About this 3rd Example, about the structure which is common in the Example mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted, and a different structure is demonstrated below. In 3rd Example, the flange part 22e has the connection parts 63 and 64 for connecting with a vehicle body side member. In the third embodiment, a motor side connecting portion 65 for connecting to the vehicle body side member is further provided at the motor end located on the other side of the motor portion A in the direction of the axis O opposite to the speed reducing portion B.

  In the in-wheel motor device 21 of the embodiment shown in FIG. 5, the upper connecting portion 63 has a connecting portion 63a at its tip, and the lower connecting portion 64 has a connecting portion 64a at its tip. And the in-wheel motor apparatus 21 of FIG. 5 is suitably attached to a double wishbone type suspension apparatus.

  FIG. 6 is a perspective view schematically showing a suspension device for suspending the in-wheel motor device 21 of FIG. Referring to FIG. 6, upper connecting portion 63a includes, for example, a ball joint or the like, and is connected to the free end of upper arm 105 extending in the vehicle width direction. The upper arm 105 swings in the vertical direction with the vehicle width direction inner end 106 as a base end. The lower connecting portion 64a includes, for example, a ball joint and is connected to the free end of the lower arm 107 extending in the vehicle width direction. The lower arm 107 swings in the vertical direction with the vehicle width direction inner end 108 as a base end.

  The motor side connecting portion 65 is a connecting portion for connecting with a vehicle body side shock absorber (also referred to as a damper), and is provided at a lower portion of the motor end portion. The motor side connecting portion 65 is integrally coupled to the motor cover 22v and protrudes from the motor cover 22v to the opposite side to the speed reduction portion B. And it has the connection part 65a in the front-end | tip. The motor side connecting portion 65 only needs to be formed on the outer peripheral edge of the motor portion A, and may be integrally coupled to the motor portion casing 22a.

  The connecting portion 65a includes, for example, a ball joint and is connected to an outer end of a linear link member 109 extending at least in the vehicle width direction. The inner end of the link member 109 is connected to one end of a substantially L-shaped link member 111. A central portion of the link member 111 is supported by a pivot 112. As a result, the link member 111 can be rotated by the pivot 112. The other end of the link member 111 is connected to the front end of the damper 115. The damper 115 is disposed horizontally so that it can expand and contract in the longitudinal direction of the vehicle body, and is attached to the vehicle body 117 at the rear end of the damper 115.

The function of the suspension device shown in FIG. 6 will be described. Upward impact load F ₁ is inputted to the in-wheel motor drive unit 21 through the wheel from the road surface, in-wheel motor device 21 is described as a representative case of moving upward from the original height position. In this case, the upper arm 105 and the lower arm 107 swing upward as indicated by arrows. At this time, since the in-wheel motor drive device 21 is pulled inward in the vehicle width, the axial force N acts on the link member 109. Since the link member 109 and the front end of the link member 111 intersect, the axial force N is converted into a moment M acting on the link member 111. The damper 115 is because it intersects the rear end of the link member 111 extends in the longitudinal direction of the vehicle, the moment M is converted to an impact load F ₂ acting on the damper 115. When an impact load F ₂ pushes the front end of the damper 115 rearward, the damper 115 absorbs an impact load F _2, pushes back slowly rear end of the link member 111. Thus, the in-wheel motor device 21 returns to the original height position. Although not shown, when a downward impact load is input to the in-wheel motor drive device 21, the damper 115 similarly absorbs it.

  The fourth embodiment of the present invention will be described with reference to the longitudinal sectional view of FIG. About this 4th Example, about the structure which is common in the Example mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted, and a different structure is demonstrated below. In the fourth embodiment, the motor side connecting portion 65 is provided at the upper portion of the motor end portion. The upper connecting portion 63 and the lower connecting portion 64 are common to the third embodiment (FIG. 5). The in-wheel motor device 21 of FIG. 7 is also preferably attached to the double wishbone suspension device. Although not shown in the figure, the impact load in the vertical direction can be absorbed by the horizontal damper 115.

  A fifth embodiment of the present invention will be described with reference to the longitudinal sectional view of FIG. About this 5th Example, about the structure which is common in the Example mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted, and a different structure is demonstrated below. In 5th Example, the connection part 64 is arrange | positioned below a wheel hub. The motor part A has a motor side connecting part 66 for connecting to the vehicle body side member at the upper part of the motor end located on the other side in the axial direction opposite to the speed reducing part B. The motor side connecting portion 66 is integrally coupled to the motor cover 22v and protrudes from the motor cover 22v to the side opposite to the speed reducing portion B. And it has the connection part 66a in the front-end | tip. The motor side connecting portion 66 may be formed on the outer peripheral edge of the motor portion A, and may be integrally coupled with the motor portion casing 22a. The in-wheel motor drive device 21 of FIG. 8 is suitably attached to a double wishbone suspension device.

  FIG. 9 is a perspective view schematically showing a suspension device for suspending the in-wheel motor device 21 of FIG. Referring to FIG. 9, upper connecting portion 66a includes, for example, a ball joint and is connected to the free end of upper arm 105 extending in the vehicle width direction. The lower connecting portion 64a includes, for example, a ball joint and is connected to the free end of the lower arm 107 extending in the vehicle width direction. The damper 116 is arranged vertically so that it can extend and contract in the vertical direction of the vehicle body, and the lower end of the damper 116 is connected to the vehicle width direction central portion of the lower arm 107. The upper end of the damper 116 is attached to the vehicle body.

  According to the suspension device shown in FIG. 9, the damper 116 extends so as to penetrate the upper arm 105, so that the layout layout under the vehicle body floor including the in-wheel motor drive device 21 and the suspension device can be made compact.

  Further, according to the suspension device shown in FIG. 9, the vertical impact load input from the road surface to the in-wheel motor drive device 21 via the wheels is applied to the wheel hub 32, the wheel hub bearing 33, the outer ring 22 c, and the deceleration. The part casing 22b and the flange part 22e can be absorbed by the damper 116 sequentially, and no impact load acts on the motor part A. Therefore, the deformation of the motor part A can be suitably prevented. Furthermore, the in-wheel motor drive device 21 can be reduced in weight by using a thin member for the motor portion casing 22a. As a result, the unsprung weight of the suspension device can be reduced and the riding comfort performance of the vehicle can be improved.

  Although not shown in the drawing, as a modification of the embodiment shown in FIG. 8, the connecting portion 63 is disposed above the axis instead of the lower connecting portion 64. And the motor side connection part 66 is arrange | positioned in the lower part of a motor end part instead of the upper part of a motor end part. Such a modification is also suitably attached to the double wishbone suspension device. Specifically, the upper connecting portion 63 of the flange portion 22e is connected to the upper arm, and this upper arm is connected to the damper. The motor side connecting portion below the motor end portion is connected to the lower arm.

  According to such a modification, the in-wheel motor drive device 21 can be reduced in weight by using a thin member for the motor portion casing 22a.

  Although the embodiments of the present invention have been described with reference to the drawings, the present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  In each example mentioned above, since flange 22e is located near a wheel, you may provide a brake caliper which brakes a wheel. In this case, the flange portion 22e has a caliper connecting portion for attaching a brake caliper. This contributes to a compact unit including the wheel brake and the in-wheel motor drive device 21.

  The in-wheel motor drive device according to the present invention is advantageously used in electric vehicles and hybrid vehicles.

  21 In-wheel data drive unit, 22 casing, 22a motor part casing, 22b reduction part casing, 22c wheel hub bearing part casing, 22e flange part, 23 stator, 24 rotor, 25 input shaft, 25a, 25b eccentric member, 26a, 26b Curved plate, 27 Outer pin, 28 Output shaft, 28c Center hole, 31 Inner pin, 32 Wheel hub, 33 Wheel hub bearing, 35 Motor rotating shaft, 61, 62, 63, 64 Connecting part, 65, 66 Motor side connecting part .

Claims (10)

A motor unit, a speed reduction unit arranged on one axial direction of the motor unit to decelerate and output the rotation of the motor unit, and a speed reduction rotation arranged further on one axial direction of the speed reduction unit and output from the speed reduction unit An in-wheel motor drive device comprising: a wheel hub that transmits the wheel hub to the wheel side; and a wheel hub bearing portion that includes a wheel hub bearing that rotatably supports the wheel hub,
A flange-shaped member disposed between the motor unit and the speed reduction unit and extending in the radial direction;
The said flange-shaped member is an in-wheel motor drive device which has a connection part for connecting an in-wheel motor drive device to a vehicle body side member. The motor unit includes a motor unit casing that forms an outline of the motor unit,
The speed reduction part includes a speed reduction part casing that forms an outline of the speed reduction part and is coupled to an outer ring of the wheel hub bearing on one side in the axial direction.
The in-wheel motor drive device according to claim 1, wherein the flange-shaped member is fixed to both the motor unit casing and the speed reduction unit casing.   The said connection part is a front side connection part which is arrange | positioned ahead of an axis line and protrudes below, and the rear side connection part which is arrange | positioned back side of an axis line and protrudes below is included. In-wheel motor drive device.   3. The in-wheel motor drive device according to claim 1, wherein the connecting portion includes an upper connecting portion disposed above the axis and a lower connecting portion disposed below the axis.   5. The in-wheel motor according to claim 4, wherein the motor unit further includes a motor-side coupling unit for coupling to a vehicle body side shock absorber at a motor end located on the other axial direction opposite to the speed reduction unit. Drive device. The connecting portion is disposed below the axis,
The said motor part further has a motor side connection part for connecting with a vehicle body side member in the upper part of the motor edge part located in the other axial direction opposite to the said deceleration part. In-wheel motor drive device. The connecting portion is disposed above the axis,
The said motor part has further a motor side connection part for connecting with a vehicle body side member in the lower part of the motor end located in the other axial direction opposite to the said deceleration part. In-wheel motor drive device.   The in-wheel motor drive device according to any one of claims 1 to 7, wherein the flange-like member has a caliper connecting portion for attaching a brake caliper. The speed reducer includes an input shaft coupled and fixed to a rotation shaft of the motor unit;
A disc-shaped eccentric member that is eccentrically coupled to the end of the input shaft from the rotational axis of the input shaft;
A revolving member that has an inner circumference attached to the outer circumference of the eccentric member so as to be relatively rotatable, and performs a revolving motion around the rotation axis along with the rotation of the input shaft;
An outer periphery engaging member that engages with an outer peripheral portion of the revolving member to cause rotation of the revolving member;
The in-wheel motor drive device in any one of Claims 1-8 which is a cycloid reduction mechanism which has a motion conversion mechanism which takes out only the rotation of the said revolution member, and transmits to the said wheel hub. The motion conversion mechanism includes a plurality of holes formed at equal intervals in the circumferential direction around the rotation axis of the revolving member,
An output shaft coupled to the wheel hub;
The in-wheel according to claim 9, wherein the in-wheel is configured by a plurality of inner engaging members that are provided at an end portion of the output shaft at equal intervals in the circumferential direction around the axis of the output shaft and respectively engage with the holes. Motor drive device.

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