JP2016222063A - In-wheel motor drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved technology of an in-wheel motor capable of reducing unit size and weight of the in-wheel motor.SOLUTION: An in-wheel motor drive device (21) comprises: a wheel hub bearing part (C) for rotatably supporting a wheel hub (32); a motor part (A) which is connected to the wheel hub bearing part and serves as an internal drive source for driving the wheel hub; a first driving system (11B) for transmitting a driving force from the motor part to the wheel hub; a first clutch (C1) which is provided in the first driving system and connects and disconnects rotation transmission of the first driving system; and a second driving system (47) which includes a universal joint (48) for connection to a drive shaft (DS) extending from outside, and transmits a driving force from an external drive source to the wheel hub via the drive shaft and the universal joint.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an in-wheel motor drive device that is arranged in a space area in a road wheel of a wheel and drives the wheel.

  In-wheel motors are not only less burdensome on the environment because they are electrically driven, but they are installed in the wheels of automobiles and drive the wheels, so they have a larger cabin space than engine cars. It can be secured and is advantageous. As such an in-wheel motor, conventionally, for example, the one described in Japanese Patent Application Laid-Open No. 2009-174592 (Patent Document 1) is known.

JP 2009-174582 A

  The in-wheel motor tends to have a large volume in order to secure a sufficient torque for driving the vehicle, and the unit size and weight of the in-wheel motor are increased. Then, in an in-wheel motor-equipped electric vehicle in which the drive motor is disposed under the spring of the suspension device, the unsprung weight of the suspension device increases compared to an on-board motor-equipped electric vehicle in which the drive motor is mounted on the body frame. The followability of the device deteriorates.

  Further, since the in-wheel motor having a large unit size is accommodated in the wheel housings formed on both sides of the vehicle body in the vehicle width direction, the wheel housing of the electric vehicle equipped with the in-wheel motor is larger than the wheel housing of a normal internal combustion engine vehicle. Then, even if we try to reduce the parts cost and production cost by using both the body of an electric vehicle equipped with an in-wheel motor and the body of an internal combustion engine vehicle, the remodeling range of the suspension device and the body becomes wide due to the difference in the size of the wheel housing. The cost will be rather high. Moreover, the electric vehicle which drives a wheel only with an in-wheel motor has a problem that the cruising distance is insufficient due to a small amount of battery.

  In view of the above circumstances, the present invention provides an improved technique for an in-wheel motor that can reduce the unit size and weight of the in-wheel motor and that can realize the same cruising distance as that of an engine vehicle. Objective.

  For this purpose, an in-wheel motor drive device according to the present invention is a wheel hub bearing that rotatably supports a wheel hub, a motor unit as an internal drive source that is connected to the wheel hub bearing, and a drive from the motor unit to the wheel hub. Including a first drive system for transmitting force, a first clutch provided in the first drive system for connecting and disconnecting rotation transmission of the first drive system, and a universal joint for connecting to a drive shaft extending from the outside A second drive system is provided that transmits drive force from the drive source to the wheel hub.

  According to the present invention, the driving force can be generated by the motor unit of the in-wheel motor driving device itself and the wheel hub can be driven by the first driving system, and the outside installed outside the in-wheel motor driving device. It is also possible to generate a driving force with the driving source and drive the wheel hub with the second driving system. Therefore, not only can the motor unit be reduced in size and weight, but also the cruising distance similar to that of an engine vehicle can be realized by driving the wheel hub of the in-wheel motor drive device with the engine. The universal joint of the second drive system includes a universal joint such as a constant velocity joint and allows free bending via the universal joint. The external drive source only needs to be installed outside the in-wheel motor drive device. For example, it may be an engine, another vehicle motor drive device, or another in-wheel motor drive device, but is particularly limited. Not.

  When the wheel hub is driven by the first drive system, the first clutch may be connected and the motor unit may be powered. On the other hand, when the wheel hub is driven by the second drive system, the first clutch may be disconnected and the external drive source may be driven. Further, when the wheel hub is driven by the first drive system and the second drive system, the first clutch may be connected and the driving force may be generated by the motor unit and the external drive source. On the other hand, if driving by the second drive system is unnecessary, the external drive source may be stopped, or the second clutch may be disconnected by providing a second clutch between the external drive source and the wheel hub. Although the installation location of the second clutch is not particularly limited, as a preferred embodiment of the present invention, the second drive system further includes a second clutch that connects and disconnects rotation transmission of the second drive system. According to this embodiment, the second clutch can be built in the in-wheel motor drive device, and the drive source can be selected in each in-wheel motor drive device.

  Although the layout of the second drive system in the in-wheel motor drive device is not particularly limited, as a preferred embodiment of the present invention, the wheel hub bearing portion and the motor portion are arranged on one and the other in the axial direction so as to be coaxial, respectively. The rotary shaft of the motor is cylindrical, the rotary shaft of the second drive system passes through the center hole of the motor rotary shaft and is drivingly coupled to the wheel hub, and the universal joint is disposed on the other side in the axial direction of the motor portion. . According to such an embodiment, the second drive system can be arranged coaxially with the wheel hub so that the layout can be made clear, which contributes to the downsizing of the in-wheel motor drive device.

  As a further preferred embodiment of the present invention, the wheel hub is arranged to be coaxially arranged between the wheel hub bearing portion arranged on one axial direction and the motor portion arranged on the other axial direction to reduce the rotation output from the motor portion. The speed reducing part further includes a first clutch, and the second clutch is disposed on the other side in the axial direction of the motor part. According to this embodiment, since a speed reduction part is further provided, it contributes to size reduction of a motor part. In a preferred embodiment of the present invention, the speed reduction unit is a cycloid speed reducer. Alternatively, the speed reduction unit may be a planetary gear set.

  In another embodiment of the present invention, the motor unit is disposed offset from the axis of the wheel hub, and the universal joint is provided at the end of the wheel hub. According to such an embodiment, the wheel hub is connected to the drive shaft via a universal joint. Therefore, a large space in the vehicle width direction of the drive shaft can be ensured while being an in-wheel motor drive device.

  As a preferred embodiment, a parallel shaft type speed reducer that is arranged in parallel with the axis of the wheel hub bearing part and the axis of the motor part and decelerates the rotation output from the motor part and transmits it to the wheel hub may be further provided.

  The first clutch and the second clutch are not particularly limited, such as an electromagnetic clutch, a hydraulic clutch, and a one-way clutch, but in a preferred embodiment, the first clutch and / or the second clutch are two-way clutches. According to this embodiment, when torque is transmitted from the driving member to the driven member, the clutch is automatically connected, and in the opposite case, the clutch is automatically disconnected. Accordingly, it is possible to selectively transmit the driving force of the internal driving source (motor unit) and the driving force of the external driving source to the wheel hub without operating the first clutch and / or the second clutch. In addition, since the two-way clutch has a simpler structure than the electromagnetic clutch or the hydraulic clutch, it contributes to the reduction in size and weight of the in-wheel motor drive device.

  As a preferred embodiment of the present invention, the motor portion has a notch shape corresponding to the swing range of the drive shaft that swings with a universal joint as a fulcrum. According to this embodiment, the suspension device that attaches the in-wheel motor drive device to the vehicle body strokes in the vertical direction or turns in the left-right direction, and the drive shaft swings with respect to the in-wheel motor drive device. However, interference between the drive shaft and the in-wheel motor drive device can be avoided. In one embodiment, when the second clutch is in the connected state and the second drive system transmits the driving force, the first clutch is in the disconnected state, and the first clutch is in the connected state and the first drive system receives the driving force. The second clutch is configured to be disengaged when transmitting.

  Thus, according to the present invention, the unit size and weight of the in-wheel motor can be reduced. Moreover, by adopting a hybrid drive source and mounting a fuel tank and engine on the vehicle body, a cruising distance similar to that of an engine vehicle can be realized.

It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes one Embodiment of this invention. It is a cross-sectional view in II-II of FIG. It is a top view which shows typically the hybrid vehicle which comprises the in-wheel motor drive device of this invention. It is a top view which shows typically the hybrid vehicle which comprises the in-wheel motor drive device which becomes a modification of this invention. FIG. 3 is an enlarged longitudinal sectional view showing a second clutch extracted from the in-wheel motor drive device of FIG. 1. FIG. 6 is a cross-sectional view showing the second clutch of FIG. 5. FIG. 6 is a cross-sectional view showing the operation of the second clutch in FIG. 5. FIG. 6 is a cross-sectional view showing the operation of the second clutch in FIG. 5. FIG. 6 is a cross-sectional view showing the operation of the second clutch in FIG. 5. FIG. 6 is a cross-sectional view showing the operation of the second clutch in FIG. 5. It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 3 is a plan view schematically showing a hybrid vehicle equipped with the in-wheel motor drive device of the present invention. First, the outline of the present invention will be described with reference to FIG. 3. An engine E and a reduction gear R are mounted on a vehicle body 11 of a hybrid vehicle, and a propeller shaft PS extends in the longitudinal direction of the vehicle body from the reduction gear R. The reduction gear R decelerates the rotation of the engine E and transmits it to the propeller shaft PS. A differential gear device DF is provided at the tip of the propeller shaft PS. Two drive shafts DS extend left and right in the vehicle width direction from the differential gear unit DF. The differential gear device DF distributes the driving force of the propeller shaft PS to the left and right drive shafts DS. This hybrid vehicle is a passenger car, and can travel at high speed on public roads like a general engine car.

  The tip of each drive shaft DS is coupled to the in-wheel motor drive device IWM. Each in-wheel motor drive unit IWM is housed in housings 11h formed on both the left and right sides of the vehicle body 11, and is disposed in a space area in the road wheel of a wheel (not shown). The in-wheel motor drive device IWM is attached to the vehicle body 11 via a suspension device (not shown). Therefore, the in-wheel motor drive device IWM can bounce and rebound in the vertical direction with respect to the vehicle body 11 together with the wheels. The wheel may be a front wheel or a rear wheel. The in-wheel motor drive device IWM may be steerable together with the wheels.

  The in-wheel motor drive device IWM includes a wheel hub bearing portion H, a motor portion M coupled to the wheel hub bearing portion H, a first clutch C1 that connects and disconnects rotation transmission from the motor portion M to the wheel hub bearing portion H, A second clutch C2 for connecting and disconnecting rotation transmission from the drive shaft DS to the wheel hub bearing portion H is provided.

  The wheel hub bearing portion H includes a wheel hub connected to the wheel and a rolling bearing that rotatably supports the wheel hub. The motor unit M is drivingly coupled to the wheel hub, and can perform a power running operation in which electric power is supplied from the vehicle body 11 to drive the wheel hub and a regenerative operation in which electric power is generated using the rotation of the wheel hub. The driving force transmission path for drivingly coupling the motor unit M and the wheel hub includes the first clutch C1 and constitutes the first driving system. The driving force transmission path for drivingly coupling the drive shaft DS and the wheel hub includes the second clutch C2 and constitutes a second driving system.

  When the first clutch C1 is connected and the second clutch C2 is disconnected, the drive rotation of the motor part M is input to the wheel hub bearing part H, and the drive shaft DS stops or idles. When the first clutch C1 is disconnected and the second clutch C2 is connected, the motor unit M stops or idles, and the drive rotation of the drive shaft DS is input to the wheel hub bearing unit H. Thus, the wheels are driven by the motor unit M or the engine E. Further, the first clutch C1 and the second clutch C2 may be connected, and the wheels may be driven by the motor unit M and the engine E. Alternatively, the first clutch C1 and the second clutch C2 may be disconnected to make the wheels free.

  Next, a modification of the present invention will be described. FIG. 4 is a plan view schematically showing a hybrid vehicle equipped with an in-wheel motor drive device according to a modification of the present invention. About this modification, about the structure which is common in embodiment of FIG. 3 mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted, and a different structure is demonstrated below. In this modified example, each in-wheel motor drive device IWM is not provided with the second clutch, but the second clutch C2 is provided on the vehicle body 11 side. The second clutch C2 is incorporated between the engine E and the differential gear device DF, for example, in the speed reducer R. The driving force transmission path for drivingly coupling the motor unit M and the wheel hub includes the first clutch C1 and constitutes the first driving system. A driving force transmission path for drivingly coupling the drive shaft DS and the wheel hub constitutes a second drive system.

  Next, the in-wheel motor drive device of the present invention will be described in detail. FIG. 1 is a longitudinal sectional view showing an in-wheel motor drive device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the embodiment. The in-wheel motor drive device 21 corresponds to the above-described in-wheel motor drive device IWM, and a motor unit A that generates a driving force as shown in FIG. 1 and a speed reducer B that decelerates and outputs the rotation of the motor unit A. And a wheel hub bearing portion C that transmits the output from the deceleration portion B to a wheel (not shown). The motor part A, the speed reduction part B, and the wheel hub bearing part C are arranged coaxially along the axis O of the in-wheel motor drive device in this order. The axis O extends in the vehicle width direction of the vehicle body 11 (FIG. 3). In the following description, regarding the axis O, the wheel hub bearing part C side is defined as one axial direction side, and the motor part A side is defined as the other axial direction side.

  The motor unit A corresponds to the motor unit M (FIG. 3) described above, and includes a cylindrical motor casing 22a, a disk-shaped motor rear cover 22t, a stator 23 fixed to the inner periphery of the motor casing 22a, and the stator 23. Is a radial gap motor provided with a rotor 24 arranged at a position facing through a gap opened radially in the inner side of the motor and a motor rotating shaft 35 that is connected and fixed to the inner side of the rotor 24 and rotates integrally with the rotor 24. . Alternatively, although not shown, the motor part A may be an axial gap motor.

  The motor casing 22a is centered on the axis O of the motor rotating shaft 35, and extends in the axial direction to form an outer shell of the motor portion A. The substantially disc-shaped partition wall 22p is integrally formed at one end of the motor casing 22a, forms a boundary with the speed reducing portion B at one end in the axis O direction of the motor portion A, and is connected to the motor rotating shaft via the rolling bearing 37. One end of 35 is rotatably supported. The substantially disc-shaped motor rear cover 22t is abutted against and fixed to the other end of the motor casing 22a, forms the end face of the motor portion A at the other end in the axis O direction of the motor portion A, and is connected to the motor via the rolling bearing 36. The other end portion of the rotating shaft 35 is rotatably supported. The motor rear cover 22t is an end portion of the motor portion A and also an end portion on the inner side in the vehicle width direction of the in-wheel motor drive device 21. A rolling bearing 46 is further arranged at the center of the motor rear cover 22t. The rolling bearing 46 rotatably supports the rotating shaft 47 of the second drive system on the other side in the axis O direction than the rolling bearing 36. The rotating shaft 47 will be described in detail later.

  One end of the motor rotating shaft 35 is coupled to a speed reducing portion input shaft 25 that is rotatably provided inside the speed reducing portion B. This coupling is spline fitting or serration fitting, and the tapered speed reducing portion input shaft 25 is inserted into and engaged with the end opening of the motor rotating shaft 35 formed in a tubular shape.

  The speed reduction part B is a cycloid speed reducer, and is coaxially arranged on one side in the axis O direction of the motor part A, and has a cylindrical speed reduction part casing 22b and an outer pin attached and fixed to the inner peripheral surface of the speed reduction part casing 22b. A holding member 45, a speed reduction portion input shaft 25 extending along the axis O, a pair of eccentric portions 25a and 25b formed on the speed reduction portion input shaft 25, and rotatably held by the respective eccentric portions 25a and 25b. A pair of curved plates 26a and 26b as revolution members, a plurality of outer pins 27 as outer peripheral engaging members that engage with the outer peripheral portions of the curved plates 26a and 26b, and a speed reducing portion output shaft 28 extending along the axis O A plurality of inner pins 31 serving as inner engagement members for taking out the rotational motion of the curved plates 26a, 26b and a gap between the pair of curved plates 26a, 26b are attached to the end surfaces of these curved plates 26a, 26b. A center collar 29 that is in contact with the curved plate to prevent inclination, a ring member 40 that fixes one end portions of the plurality of inner pins 31, a reinforcing member 61 that fixes the other end portions of the plurality of inner pins 31, and One clutch C1 is provided.

  The speed reduction unit input shaft 25 extends along the axis O of the motor rotation shaft 35, and the end of the speed reduction unit input shaft 25 on the side closer to the motor unit A of both ends thereof is coupled to one end of the motor rotation shaft 35. . The end of the speed reduction part input shaft 25 on the side far from the motor part A is rotatably supported via a rolling bearing 39. A pair of eccentric portions 25 a and 25 b are formed eccentrically from the axis O on the outer periphery of the central region in the direction of the axis O of the deceleration portion input shaft 25. The speed reducer input shaft 25 is rotatably supported by the reinforcing member 61 by the rolling bearing 38 on the side closer to the motor part A than the eccentric parts 25a and 25b.

  Each eccentric part 25a, 25b is a disk shape, and is eccentric from the axis O and is provided on the deceleration part input shaft 25. Further, the eccentric parts 25a and 25b form a pair of two and are arranged apart from each other in the direction of the axis O, and are provided with a phase difference of 180 ° in the circumferential direction so as to cancel out vibrations generated by the centrifugal force due to the eccentric movement. It has been.

  The motor rotation shaft 35 and the speed reduction part input shaft 25 constitute a motor side rotation member that transmits the driving force of the motor part A to the speed reduction part B, and rotate together.

  Referring to FIG. 2, curved plate 26b has a disc shape, and its outer peripheral portion is formed in a waveform. Specifically, the outer peripheral portion of the curved plate 26 b is a plurality of curved concave portions formed of a trochoidal curve such as an epitrochoid and recessed in the radial direction, and meshes with the outer pin 27. The curved plate 26b has a plurality of through holes 30a and 30b penetrating from one end face to the other end face. A plurality of through holes 30a are provided at equal intervals on the circumference centering on the rotation axis X of the curved plate 26b, and receive the inner pins 31. Moreover, the through-hole 30b is provided in the autorotation axis X of the curved plate 26b, and becomes an inner periphery of the curved plate 26b. The curved plate 26b is attached to the outer periphery of the eccentric portion 25b so as to be relatively rotatable. The inner pin 31 includes a needle roller bearing, and includes an inner pin main body 31a, a plurality of needle rollers 31b, and a bearing outer ring 31c. The inner pin main body 31a passes through the bearing outer ring 31c, and the needle rollers 31b are disposed in an annular space between the inner pin main body 31a and the bearing outer ring 31c. The outer diameter of the inner pin 31, that is, the outer diameter of the bearing outer ring 31c is sufficiently smaller than the inner diameter of the through hole 30a, and a part of the outer peripheral surface of the inner pin 31 contacts the hole wall surface of the through hole 30a. The remaining part of the outer peripheral surface of the through hole 30 is not in contact with the hole wall surface of the through hole 30a. The outer peripheral surface of the bearing outer ring 31c is in contact with the hole wall surface of the through hole 30a while rolling.

  The curved plate 26b is rotatably supported by the rolling bearing 41 with respect to the eccentric portion 25b. In order to facilitate understanding, a part of the rolling bearing 41 in the circumferential direction is shown in FIG. The rolling bearing 41 includes a plurality of rollers 44 disposed between an annular inner ring member 42 having an inner raceway surface 42a on the outer diameter surface and a hole wall surface of the through-hole 30b serving as the outer raceway surface. And a cylindrical roller bearing provided with a cage (not shown) that holds the interval between the rollers 44 adjacent in the circumferential direction. Alternatively, it may be a deep groove ball bearing. The inner diameter surface of the inner ring member 42 is fitted to the outer diameter surface of the eccentric portion 25b. The inner ring member 42 further has a pair of flanges facing each other with the inner raceway surface 42a interposed therebetween. The same applies to the curved plate 26a.

  A plurality of outer pins 27 shown in FIG. 1 are provided at equal intervals on a circumferential track centering on the axis O of the motor side rotating member (see FIG. 2), and extend parallel to the axis O. When the two pair of curved plates 26a, 26b revolve around the axis O, the curved concave portions on the outer periphery of the curved plates 26a, 26b engage with the outer pin 27, and the curved plates 26a, 26b rotate. Give rise to

  The outer pin 27 disposed inside the speed reduction unit casing 22b may be directly connected and fixed to the inner wall surface of the speed reduction unit casing 22b, but is preferably attached and fixed to the inner wall surface of the speed reduction unit casing 22b. It is held by the outer pin holding member 45. More specifically, as shown in FIG. 1, both axial ends of the outer pin 27 are rotatably supported by needle roller bearings 27 a (rolling bearings) attached to the outer pin holding member 45. Thus, by attaching the outer pin 27 to the outer pin holding member 45 via the rolling bearing so as to be rotatable and rotatable, the contact resistance due to the engagement with the curved plates 26a and 26b can be reduced.

  In the ring member 40, holes for fixing one end of the inner pin 31 are formed at equal intervals on a circumference around the axis O. One end portion of the speed reducer input shaft 25 is passed through the center hole of the ring member 40.

  The speed reduction part output shaft 28 has a flange part 28c at the end part on the motor part A side and a shaft part 28d on the wheel hub bearing part C side. A first clutch C1 is interposed between the flange portion 28c and the ring member 40. The first clutch C1 is the same as the second clutch C2 described in detail later, and includes a driving member disposed on the inner diameter side and a driven member disposed on the outer diameter side. When the driving member is on the driving side, the first clutch C1 is automatically connected to transmit the torque of the driving member to the driven member, and the driving member and the driven member rotate integrally. On the other hand, when the driven member is on the driving side, the first clutch C1 is automatically disconnected and the torque of the driven member is not transmitted to the driven member, and the driving member is idled or stopped.

  The outer peripheral edge of the flange portion 28c is larger in diameter than the inner peripheral edge of the ring member 40, and is coupled to the driven member on the outer diameter side of the first clutch C1. The inner peripheral edge of the ring member 40 having a small diameter is coupled to the drive member on the inner diameter side of the first clutch C1.

  The outer ring of the rolling bearing 39 described above is attached and fixed to the flange portion 28c. And the one end of the deceleration part input shaft 25 attached and fixed to the inner ring | wheel of the bearing 39 is supported. The speed reduction part B is a driving force transmission path from the speed reduction part input shaft 25 to the speed reduction part output shaft 28 and constitutes a first drive system that drives and connects the motor rotation shaft 35 and the wheel hub 32. The first drive system is provided with a first clutch C1.

  A reinforcing member 61 is provided at the other end of the inner pin 31 on the side away from the ring member 40. The reinforcing member 61 is a flange-shaped large-diameter disc portion 61b that is coupled and fixed to the tips of the plurality of inner pins 31 inside the speed reduction portion B, and is coaxially formed adjacent to the large-diameter disc portion 61b. A small-diameter disk part 61c having a smaller diameter than the part 61b and a smaller-diameter cylindrical part 61d extending from the inner peripheral edge of the small-diameter disk part 61c to the motor part A are included. The large-diameter disc portion 61b is centered on the axis O, the small-diameter disc portion 61c is disposed closer to the motor portion A than the large-diameter disc portion 61b, and the cylindrical portion 61d is directed from the small-diameter disc portion 61c toward the motor portion A. Extending along the axis O.

  Since the load applied to a part of the inner pins 31 from the two curved plates 26a, 26b is supported by all the inner pins 31 via the large-diameter disk portion 61b of the reinforcing member 61 and the ring member 40, The stress acting on each inner pin 31 can be reduced and the durability can be improved. A rolling bearing 38 is attached to the inner peripheral surface of the small-diameter disk portion 61c, and the rolling bearing 38 supports the speed reduction portion input shaft 25 rotatably.

  The reinforcing member 61 is coupled to the ring member 40 via the inner pin 31 and rotates integrally with the speed reducing portion output shaft 28 when the first clutch C1 is connected. The reduction part output shaft 28, the 1st clutch C1, the ring member 40, and the reinforcement member 61 comprise the wheel side rotation member which transmits the output of the reduction part B to the wheel hub 32, as shown in FIG.

  Roller bearings 62 and 64 are disposed at both ends of the outer pin holding member 45. The rolling bearings 62 and 64 rotatably support the wheel side rotating member. The rolling bearing 62 is disposed on the side close to the motor part A, and the rolling bearing 64 is disposed on the side close to the wheel hub bearing part C.

  The wheel hub bearing portion C corresponds to the wheel hub bearing portion H (FIG. 3) described above, and includes an inner ring 33c, a wheel hub 32 as a rotating shaft, a rolling element 33, and a non-rotating outer ring member 33a as shown in FIG. It is a rolling bearing having. The wheel hub 32 is coaxially arranged on one side of the speed reduction unit output shaft 28 in the axis O direction, and is connected and fixed to the speed reduction unit output shaft 28. The wheel hub bearing portion C is an end portion on the outer side in the vehicle width direction of the in-wheel motor drive device 21.

  The inner ring 33c of the rotating member is fitted and fixed to the outer peripheral surface of the wheel hub 32, and the outer ring member 33a of the non-rotating member is fixed to one end of the speed reduction portion casing 22b by a bolt 33b. The speed reduction part casing 22b that forms the outline of the speed reduction part B, the motor casing 22a and the motor rear cover 22t that form the outline of the motor part A are coupled to each other by bolts, and the partition wall 22p is integrally formed with the motor casing 22a. As a whole, one casing 22 is configured. As described above, the casing 22 includes a plurality of casing members or casing portions.

  The wheel hub bearing portion C is a double-row angular contact ball bearing having a large number of rolling elements 33 in two rows, and is arranged between the outer ring member 33a and the inner ring 33c on the side where the rolling elements 33 in the first row are close to the speed reduction portion B. The second row of rolling elements 33 is disposed between the outer ring member 33 a and the wheel hub 32 on the side far from the speed reduction portion B.

  The wheel hub 32 includes a cylindrical hollow portion 32a and a wheel mounting flange portion 32b that protrudes from one end of the hollow portion 32a in the outer diameter direction. The shaft portion 28d is spline-fitted or serrated-fitted into the central hole of the hollow portion 32a. An inner raceway surface that is in rolling contact with the second row of rolling elements 33 is formed on the outer peripheral surface of the hollow portion 32a. A wheel load wheel (not shown) is connected and fixed to the wheel mounting flange portion 32b by a bolt 32c.

  The shaft portion 28d has a cylindrical shape, and one end of the rotating shaft 47 is inserted, and both are spline fitted or serrated fitted. In this way, the rotating shaft 47 is connected to the speed reducing portion output shaft 28 so as not to be relatively rotatable. The rotating shaft 47 extends along the axis O, and passes through the central hole of the motor rotating shaft 35 and the speed reducing portion input shaft 25 that are cylindrical, that is, the cylindrical motor side rotating member. The other end of the rotating shaft 47 is rotatably supported by the motor rear cover 22t via a rolling bearing 46.

  The other end of the rotating shaft 47 is formed in a cylindrical shape having a larger diameter than the one end region and the center region, and incorporates the second clutch C2. A shaft portion 48s of the constant velocity joint 48 is inserted into the center of the second clutch C2. The second clutch C2 is interposed between the rotating shaft 47 and the shaft portion 48s and connects or disconnects both.

  The shaft portion 48s is connected to the end portion of the drive shaft DS through a constant velocity joint 48 as a universal joint. The drive shaft DS swings in an arbitrary direction with a constant velocity joint 48 as a fulcrum as shown by an arc arrow in FIG. The swing angle of the drive shaft DS with respect to the axis O corresponds to the stroke amount of a suspension device (not shown) that attaches the in-wheel motor drive device 21 to the vehicle body so that the stroke is possible.

  The aforementioned deceleration unit B transmits the driving force of the motor unit A included in the in-wheel motor drive device 21 to the wheel hub 32 as a first drive system. On the other hand, the driving force transmission path from the constant velocity joint 48 to the speed reduction unit output shaft 28 via the rotary shaft 47 constitutes a second drive system for drivingly coupling the drive shaft DS and the wheel hub 32. The second drive system includes the second clutch C <b> 2 and transmits the drive force of an external drive source, such as an engine, installed outside the in-wheel motor drive device 21 to the wheel hub 32.

  A notch 22u is formed in the motor rear cover 22t so that the swinging drive shaft DS does not interfere with the in-wheel motor drive device 21. The notch 22u is a surface inclined with respect to the axis O passing through 48, and specifically, is tapered so as to protrude in the direction of the axis O as the distance from the rolling bearing 46 increases in the outer diameter direction. This taper angle corresponds to the swing range of the drive shaft DS.

  Next, the second clutch C2 will be described in detail.

  FIG. 5 is an enlarged longitudinal sectional view showing the second clutch taken out from the in-wheel motor drive device of FIG. 6 is a cross-sectional view showing the second clutch of FIG. The second clutch C2 is a two-way clutch and transmits torque from the shaft portion 48s toward the rotating shaft 47, but cuts off reverse torque.

  The other end 47e of the rotating shaft 47 has a cylindrical shape that opens toward the other end in the axis O direction, and the outer cylinder 66 (the aforementioned driven member) of the second clutch C2 is fixed to the inner periphery of the other end 47e. . The inner periphery of the outer cylinder 66 constitutes a clutch surface 66i.

  The outer periphery of the shaft portion 48s (the aforementioned drive member) that is passed through the center hole of the outer cylinder 66 is formed in a regular polygon in a cross section perpendicular to the axis O, and constitutes the cam surface 67 of the second clutch C2. The plurality of cam surfaces 67 are flat surfaces arranged at an equal distance from the axis O and face the clutch surface 66i. The clutch surface 66i and the center of each cam surface 67 in the circumferential direction have a large distance, and the distance between the clutch surface 66i and the cam surface 67 decreases from the circumferential center of the cam surface 67 toward the circumferential end.

  An engaging member 68 of the second clutch C2 is disposed between each cam surface 67 and the clutch surface 66i. Each engagement element 68 is a cylindrical roller extending in parallel with the axis O. The plurality of engagement elements 68 are held by a ring-shaped holder 69. The retainer 69 of the second clutch C2 is disposed in an annular gap between the outer cylinder 66 and the shaft portion 48s, and the circumferential position of all the engaging elements 68 is unified with respect to the axis O. Therefore, each engagement element 68 moves simultaneously to the center portion in the circumferential direction of each cam surface, or simultaneously moves to the circumferential end portion of each cam surface. The first clutch C1 has the same structure as the second clutch C2.

Next, the function and operation of the second clutch C2 will be described.
7 to 10 are cross-sectional views showing the operation of the second clutch of FIG. When the torque D1 in the positive direction is input from the engine E (FIG. 3) to the shaft portion 48s, as shown in FIG. It enters the gap between the surface 67 and the clutch surface 66i. As a result, the second clutch C2 enters the connected state, and the outer cylinder 66 and the shaft portion 48s rotate integrally as indicated by the arrows having the same length.

  When torque R1 in the reverse direction is input from the engine E (FIG. 3) to the shaft portion 48s, as shown in FIG. 8, all the engagement elements 68 roll and move to the other circumferential end of the cam surface 67. It enters the gap between the cam surface 67 and the clutch surface 66i. As a result, the second clutch C2 enters a connected state, and the outer cylinder 66 rotates integrally with the shaft portion 48s as indicated by arrows having the same length. As described above, the second clutch C2 enters the connected state when torques D1 and R1 in two directions (forward rotation and reverse rotation) are input from the engine E, and transmits the torques D1 and R1 to the wheel hub 32 via the rotary shaft 47. To do.

  On the other hand, when the outer cylinder 66 rotates in the forward direction by the arrow D2 as shown in FIG. 9 because the wheel hub 32 rotates fast while the engine E does not generate torque, all the engaging elements 68 are cam surfaces. It rolls and moves to the center part of the circumferential direction of 67, and cancels the wedge action mentioned above. As a result, the second clutch C2 is disconnected, and the outer cylinder 66 does not transmit torque to the shaft portion 48s. The outer cylinder 66 freely rotates at a higher speed than the shaft portion 48s as indicated by a long arrow. At this time, the shaft portion 48s may freely rotate at a low speed as indicated by a short arrow, or may stop.

  Also, as shown in FIG. 10, even when the outer cylinder 66 rotates in the reverse direction by the arrow R2, all the engaging elements 68 roll to the center in the circumferential direction of the cam surface 67, and the above-mentioned wedge action is released. As a result, the second clutch C2 is disengaged and the other end 47e does not transmit torque to the shaft 48s. The outer cylinder 66 freely rotates at a higher speed than the shaft portion 48s as indicated by a long arrow. At this time, the shaft portion 48s may freely rotate at a low speed as indicated by a short arrow, or may stop.

  The function and action of the first clutch C1 are the same as those of the second clutch C2, and the torque in the two directions of the ring member 40 is transmitted to the speed reduction unit output shaft 28, but the torque in the two directions of the speed reduction unit output shaft 28 is transmitted to the ring. It is not transmitted to the member 40.

  As a result, when the motor part A is powered and the engine E is idling or stopped, the first clutch C1 is automatically connected and the second clutch C2 is automatically disconnected, and the output rotation of the motor part A is decelerated. It is decelerated by the part B and transmitted to the wheel hub bearing part C. On the contrary, when the motor part A is stopped and the engine speed is increased, the first clutch C1 is automatically disconnected and the second clutch C2 is automatically connected, and the output rotation of the engine E is the wheel hub bearing. Part C is transmitted.

  According to this embodiment, in addition to driving the wheel hub 32 of the in-wheel motor drive device 21 by the motor part A of the in-wheel motor drive device 21 and the first drive system, it is installed outside the in-wheel motor drive device 21. The wheel hub 32 of the in-wheel motor drive device 21 can be driven by the engine E (FIGS. 3 and 4) and the second drive system. Therefore, not only can the motor unit A be made smaller and lighter than a conventional in-wheel motor, but also the driving distance hub similar to that of an engine vehicle can be realized by driving the wheel hub 32 with the engine E. it can.

  Next, another embodiment of the present invention will be described. FIG. 11 is a longitudinal sectional view showing a modification of the present invention. Regarding the other embodiments, the same reference numerals are given to the configurations common to the above-described embodiments, and the description thereof will be omitted, and different configurations will be described below. In another embodiment, a parallel shaft type speed reducer is adopted instead of the above-described cycloid speed reducer (FIGS. 1 and 2).

  The reduction part B ′ of the parallel shaft type reduction gear includes an input gear 71, intermediate gears 72 and 73, and an output gear 74. These gears are all external gears, and the number of teeth and the outer diameter of the intermediate gear 72 are larger than those of the input gear 71, the intermediate gear 73 is smaller than the intermediate gear 72, and the output gear 74 is smaller than the intermediate gear 73. large. The input gear 71 provided at the end of the speed reduction unit input shaft 25 is coaxially arranged with the axis P of the motor rotation shaft 35 and meshes with the intermediate gear 72. The axis P of the motor rotation shaft 35 is arranged offset from the axis O of the wheel hub 32.

  The intermediate gears 72 and 73 are provided on an intermediate shaft 75 extending in parallel with the axis P. The axis Q of the intermediate shaft 75 is also offset from the axis O. The intermediate gear 73 meshes with the output gear 74. The output gear 74 is attached to the flange portion 28 c of the speed reduction portion output shaft 28 and is coaxially arranged with the axis O. A first clutch C1 is interposed between the output gear 74 and the flange portion 28c.

  The first clutch C1 is a two-way clutch that transmits torque from the output gear 74 to the flange portion 28c, but does not transmit torque from the flange portion 28c to the output gear 74.

  As a result, when the motor part A is in a power running operation and the engine E is idling or stopped, the first clutch C1 is connected and the second clutch C2 is disconnected, and the output rotation of the motor part A is decelerated by the reduction part B ′. Is transmitted to the wheel hub bearing portion C. On the other hand, when the motor part A is stopped and the rotational speed of the engine E increases, the first clutch C1 is disconnected and the second clutch C2 is connected, and the output rotation of the engine E is transmitted to the wheel hub bearing part C. .

  The axis P of the motor part A, the axis Q of the speed reduction part B ′, and the axis O of the wheel hub bearing part C are arranged offset in parallel and extend in the vehicle width direction of the vehicle body 11 (FIG. 3). Further, the speed reduction part B ′ and the wheel hub bearing part C are arranged so as to overlap in the axial direction. The motor part A is disposed at a position different in the axial direction with respect to the speed reducing part B ′ and the wheel hub bearing part C, the motor part A is located on the inner side in the vehicle width direction, and the wheel hub bearing part C is located on the outer side in the vehicle width direction. At least the wheel hub bearing portion C and the speed reduction portion B ′ of the in-wheel motor drive device 21 are disposed in the space area inside the road wheel of the wheel.

  According to the embodiment shown in FIG. 11, the wheel hub bearing portion C is disposed offset from the motor portion A, so that the dimension in the axis O direction of the in-wheel motor drive device 21 is made smaller than that in the embodiment shown in FIG. 1. be able to. Therefore, the length of the drive shaft DS can be made larger than that of the embodiment shown in FIG. 1, and the stroke range of the suspension device and the maximum turning angle can be sufficiently secured.

  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.

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

11 body, 11h housing,
21 in-wheel motor drive device, 22 casing,
22a motor casing, 22b reduction gear casing,
22t motor rear cover, 25 speed reducer input shaft,
27 Outer pin, 28 Reducer output shaft, 31 Inner pin,
32 wheel hub, 33 rolling element, 33a outer ring member,
35 motor rotating shaft, 40 ring member, 47 rotating shaft,
48 constant velocity joint, 61 reinforcing member, 66 outer cylinder,
66i clutch surface, 67 cam surface, 68 engagement element,
69 cage, 71 input gear, 72, 73 intermediate gear,
74 output gear, 75 intermediate shaft, C1 first clutch,
C2, second clutch, DF differential gear device,
DS drive shaft, E engine,
PS propeller shaft, R reducer.

Claims (10)

A wheel hub bearing that rotatably supports the wheel hub;
A motor part as an internal drive source connected to the wheel hub bearing part;
A first drive system for transmitting a drive force from the motor unit to the wheel hub;
A first clutch provided in the first drive system for connecting and disconnecting rotation transmission of the first drive system;
An in-wheel motor drive device comprising: a universal joint for connecting to a drive shaft extending from the outside, and a second drive system that transmits a drive force from an external drive source to the wheel hub.   The in-wheel motor drive device according to claim 1, wherein the second drive system further includes a second clutch that connects and disconnects rotation transmission of the second drive system. The wheel hub bearing part and the motor part are respectively arranged on one and the other in the axial direction so as to be coaxial,
The motor rotating shaft of the motor part is cylindrical,
A rotation shaft of the second drive system passes through a center hole of the motor rotation shaft and is drivingly coupled to the wheel hub;
The in-wheel motor drive device according to claim 2, wherein the universal joint is disposed on the other side in the axial direction of the motor unit. Deceleration that is coaxially arranged between the wheel hub bearing portion arranged on one side in the axial direction and the motor portion arranged on the other side in the axial direction and decelerates the rotation output from the motor portion and transmits it to the wheel hub. Further comprising
The deceleration unit includes the first clutch,
The in-wheel motor drive device according to claim 3, wherein the second clutch is arranged on the other side in the axial direction of the motor unit.   The in-wheel motor drive device according to claim 4 in which said deceleration part is a cycloid reduction gear. The motor part is arranged offset from the axis of the wheel hub;
The in-wheel motor drive device according to claim 2, wherein the universal joint is provided at an end portion of the wheel hub.   The parallel shaft type speed reducer which is arranged in parallel with the axis of the wheel hub bearing part and the axis of the motor part, and which decelerates the rotation outputted from the motor part and transmits it to the wheel hub. The in-wheel motor drive device of description.   The in-wheel motor drive device according to any one of claims 2 to 7, wherein the first clutch and / or the second clutch is a two-way clutch.   The in-wheel motor drive device according to any one of claims 1 to 8, wherein the motor portion is formed in a cutout shape corresponding to a swing range of the drive shaft that swings around the universal joint. When the second clutch is connected and the second drive system transmits driving force, the first clutch is disconnected,
The in-wheel according to any one of claims 2 to 8, wherein the second clutch is configured to be in a disconnected state when the first clutch is in a connected state and the first drive system transmits a driving force. Motor drive device.

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