JP2008208911A - In-wheel motor drive mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in-wheel motor drive mechanism smaller, lighter, superior in durability and highly reliable. <P>SOLUTION: The in-wheel motor drive mechanism 21 comprises a casing 22, a motor part A for rotationally driving a motor side rotating member 25, a speed reduction part B for reducing the rotation of the motor side rotating member and transmitting it to a wheel side rotating member 28, and a wheel hub 32 fixedly connected to the wheel side rotating member 28. The speed reduction part B has a cycloid reduction mechanism, wherein an inner pin 31 is supported at its one-side end by the wheel side rotating member 28 and retained at its other-side end in a revolution permissible state by the casing 22. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an in-wheel motor drive device in which an output shaft of an electric motor and a wheel hub are connected via a reduction gear.

  A conventional in-wheel motor drive device 101 is described in, for example, Japanese Patent Application Laid-Open No. 2006-258289 (Patent Document 1). Referring to FIG. 6, an in-wheel motor drive device 101 includes a motor unit 103 that generates a driving force inside a casing 102 that is attached to a vehicle body, a wheel hub bearing unit 104 that is connected to a wheel, and a motor unit 103. And a speed reduction portion 105 that reduces the rotation and transmits the reduced speed to the wheel hub bearing portion 104.

  In the in-wheel motor drive device 101 having the above configuration, a low torque and high rotation motor is employed for the motor unit 103 from the viewpoint of making the device compact. On the other hand, the wheel hub bearing portion 104 requires a large torque to drive the wheel. Therefore, a cycloid reducer that is compact and can provide a high reduction ratio may be employed as the reduction unit 105.

Moreover, the speed reduction part 105 to which the conventional cycloid reduction gear is applied includes a motor-side rotating member 106 having eccentric parts 106a and 106b, curved plates 107a and 107b disposed on the eccentric parts 106a and 106b, and curved plates 107a and 107b. A rolling bearing 111 that rotatably supports the motor-side rotating member 106, a plurality of outer pins 108 that engage with the outer peripheral surfaces of the curved plates 107a and 107b to cause the curved plates 107a and 107b to rotate. And an inner pin 109 that transmits the rotation of the curved plates 107a and 107b to the wheel-side rotating member 110.
JP 2006-258289 A

  When the in-wheel motor drive device 101 described in the above publication is mounted on an electric vehicle, if a radial load or moment load is applied to the wheel hub bearing portion 104 due to turning or rapid acceleration / deceleration of the electric vehicle, The hub bearing 104 is eccentric or tilted.

  Here, the wheel-side rotating member 110 has one end connected to the speed reducer and the other end fixedly connected to the wheel hub bearing 104. The side rotating member 110 also undergoes internal deformation such as eccentricity and inclination. This not only hinders the smooth rotation of the speed reducing unit 105 but also may cause damage to the components due to an excessive load applied to each component.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an in-wheel motor drive device that is small, light, excellent in durability, and high in reliability.

  An in-wheel motor drive device according to the present invention includes a casing, a motor unit that rotationally drives the motor-side rotating member, a speed-reducing unit that decelerates the rotation of the motor-side rotating member and transmits the rotation to the wheel-side rotating member, and wheel-side rotation And a wheel hub fixedly connected to the member. The motor side rotation member further has an eccentric part. The speed reduction part is rotatably held by the eccentric part and engages with a revolution member that performs a revolution movement around its rotation axis as the motor side rotation member rotates, and an outer periphery of the revolution member to revolve. The outer peripheral engagement member that causes the rotation of the member, the inner pin that revolves around the rotation axis of the wheel-side rotating member, and a diameter larger than the outer diameter of the inner pin by a predetermined amount in the thickness direction of the rotating member. And a motion conversion mechanism that includes a through hole that receives the inner pin, converts the rotational motion of the revolving member into a rotational motion around the rotational axis of the motor-side rotating member, and transmits the rotational motion to the wheel-side rotating member. And the one side edge part of an inner pin is fixed to the wheel side rotation member, and the other side edge part is hold | maintained in the state where revolution was permitted by the casing.

  By using the inner pins as both-end supported as in the above configuration, the wheel-side rotating member can be prevented from being tilted by a radial load or a moment load applied to the wheel hub. As a result, it is possible to obtain a highly reliable in-wheel motor drive device that maintains the smooth operation of the speed reduction unit.

  As one embodiment, a bearing is disposed between the other end portion of the inner pin and the casing. More specifically, the bearing is disposed between the inner ring as the non-rotating side race ring whose inner diameter surface is fixed to the casing, the outer ring as the rotation side race ring whose outer diameter surface contacts the inner pin, and the inner ring and the outer ring. It is a rolling bearing provided with a plurality of rolling elements. As a result, the smooth revolving motion of the inner pin is not hindered. As a result, torque loss of the in-wheel motor drive device can be reduced.

  According to this invention, it can be set as the structure which can prevent that a wheel side rotation member inclines by using an inner pin as both-end support. As a result, it is possible to prevent troubles such as defective rotation and breakage of the speed reduction unit, and to obtain an in-wheel motor drive device having excellent durability and high reliability.

  With reference to FIG. 4 and FIG. 5, the electric vehicle 11 provided with the in-wheel motor drive device which concerns on one Embodiment of this invention is demonstrated. 4 is a plan view of the electric vehicle 11, and FIG. 5 is a view of the electric vehicle 11 as viewed from the rear.

  Referring to FIG. 4, an electric vehicle 11 includes an in-wheel motor drive device that transmits driving force to a chassis 12, front wheels 13 as steering wheels, rear wheels 14 as drive wheels, and left and right rear wheels 14. 21. Referring to FIG. 5, the rear wheel 14 is housed inside a wheel housing 12 a of the chassis 12 and is fixed to the lower portion of the chassis 12 via a suspension device (suspension) 12 b.

  The suspension device 12b supports the rear wheel 14 by a suspension arm extending to the left and right, and suppresses vibration of the chassis 12 by absorbing vibration received by the rear wheel 14 from the ground by a strut including a coil spring and a shock absorber. Furthermore, a stabilizer that suppresses the inclination of the vehicle body when turning is provided at the connecting portion of the left and right suspension arms. The suspension device 12b is an independent suspension type in which the left and right wheels can be moved up and down independently in order to improve the followability to the road surface unevenness and efficiently transmit the driving force of the driving wheels to the road surface. Is desirable.

  The electric vehicle 11 needs to be provided with a motor, a drive shaft, a differential gear mechanism, and the like on the chassis 12 by providing an in-wheel motor drive device 21 for driving the left and right rear wheels 14 inside the wheel housing 12a. This eliminates the need to secure a wide cabin space and control the rotation of the left and right drive wheels.

  On the other hand, in order to improve the running stability of the electric vehicle 11, it is necessary to suppress the unsprung weight. In addition, in-wheel motor drive device 21 is required to be downsized in order to secure a wider cabin space. Therefore, an in-wheel motor drive device 21 according to an embodiment of the present invention as shown in FIG. 1 is employed.

  With reference to FIGS. 1-3, the in-wheel motor drive device 21 which concerns on one Embodiment of this invention is demonstrated. 1 is a schematic cross-sectional view of the in-wheel motor drive device 21, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and FIG. 3 is an enlarged view around the eccentric portions 25a and 25b in FIG.

  First, referring to FIG. 1, an in-wheel motor drive device 21 includes a motor unit A that generates a driving force, a deceleration unit B that decelerates and outputs the rotation of the motor unit A, and an output from the deceleration unit B. A wheel hub bearing portion C for transmitting to the drive wheel 14 is provided, and the motor portion A and the speed reduction portion B are accommodated in the casing 22 and attached to the wheel housing 12a of the electric vehicle 11 as shown in FIG.

  The motor unit A includes a stator 23 fixed to the casing 22, a rotor 24 disposed at a position facing the inner side of the stator 23 with an axial clearance, and a rotor 24 fixedly connected to the inner side of the rotor 24. It is an axial gap motor provided with the motor side rotation member 25 which rotates integrally. Further, a sealing member (not shown) is provided on the end surface of the motor part A opposite to the speed reduction part B in order to prevent dust from entering the motor part A.

  The rotor 24 includes a flange-shaped rotor portion 24a and a cylindrical hollow portion 24b, and is rotatably supported with respect to the casing 22 by rolling bearings 34a and 34b. In addition, a sealing member 35 is provided between the casing 22 and the rotor 24 in order to prevent the lubricant encapsulated in the speed reduction part B from entering the motor part A.

  The motor-side rotation member 25 is disposed from the motor part A to the speed reduction part B in order to transmit the driving force of the motor part A to the speed reduction part B, and has eccentric parts 25a and 25b in the speed reduction part B. One end of the motor-side rotating member 25 is fitted to the rotor 24 and is supported by rolling bearings 36a and 36b at both ends of the speed reduction unit B. Further, the two eccentric portions 25a and 25b are provided with a 180 ° phase change in order to cancel the centrifugal force due to the eccentric motion.

  The deceleration part B is held at a fixed position on the casing 22 and curved plates 26a and 26b as revolving members that are rotatably held by the eccentric parts 25a and 25b, and engages with the outer peripheral parts of the curved plates 26a and 26b. A plurality of outer pins 27 as outer peripheral engagement members, a motion conversion mechanism that transmits the rotation of the curved plates 26 a and 26 b to the wheel-side rotation member 28, and a counterweight 29 are provided.

  The wheel side rotation member 28 includes a flange portion 28a and a shaft portion 28b. The end surface of the flange portion 28a has holes for fixing the inner pins 31 at equal intervals on the circumference around the rotation axis of the wheel side rotation member 28, and the outer diameter surface of the hollow portion 28b is a wheel hub bearing. The inner diameter surface of 33 is fitted.

  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 rotation axis of the curved plate 26a, and receive inner pins 31 described later. The through hole 30b is provided at the center of the curved plate 26a and passes through the eccentric portion 25a.

  The curved plate 26a is rotatably supported by the rolling bearing 39 with respect to the eccentric portion 25a. This rolling bearing 39 is fitted to the eccentric portion 25a, an inner ring 39a having an inner raceway surface on the outer diameter surface, an outer ring 39b fitted to the inner wall surface of the through hole 30b and having an outer raceway surface on the inner diameter surface, It is a deep groove ball bearing provided with balls 39c as a plurality of rolling elements disposed between an inner ring 39a and an outer ring 39b, and a cage (not shown) that holds the plurality of balls 39c.

  The outer pins 27 are provided at equal intervals on a circumferential track centering on the rotation axis of the motor side rotation member 25. This coincides with the revolution trajectory of the curved plates 26a and 26b. Therefore, when the curved plates 26a and 26b revolve, the curved waveform and the outer pin 27 engage with each other, and the curved plates 26a and 26b rotate. Cause it to occur. Further, in order to reduce the contact resistance with the curved plates 26a, 26b, a needle roller bearing 27a is provided at a position in contact with the outer peripheral surface of the curved plates 26a, 26b.

  The counterweight 29 has a disc shape and has a through-hole that fits with the motor-side rotation member 25 at a position off the center, in order to counteract the unbalanced inertia couple generated by the rotation of the curved plates 26a and 26b. The eccentric portions are arranged outside the eccentric portions 25a and 25b with a 180 ° phase change.

Here, referring to FIG. 3, if the center point between the two curved plates 26a, 26b is G, the distance between the central point G and the center of the curved plate 26a is the right side of the central point G in FIG. L ₁ , the mass of the curved plate 26 a is m ₁ , the eccentricity of the center of gravity of the curved plate 26 a from the rotational axis is ε ₁ , the distance between the center point G and the counterweight 29 is L ₂ , and the mass of the counterweight 29 is Assuming that m ₂ and the amount of eccentricity of the center of gravity of the counterweight 29 from the rotation axis are ε ₂ , the relationship satisfies L ₁ × m ₁ × ε ₁ = L ₂ × m ₂ × ε ₂ . A similar relationship is also established between the curved plate 26b on the left side of the center point G in FIG.

  The motion conversion mechanism includes a plurality of inner pins 31 that are both supported by the casing 22 and the wheel-side rotating member 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 rotational axis of the wheel side rotation member 28, one end is fixed to the wheel side rotation member 28, and the other end is The outer diameter surface of the bearing 37 provided in the casing 22 is abutted and supported.

  Further, a retaining portion 31b that prevents the inner pin 31 from coming off from the through hole 30a is provided at the other end portion. Further, in order to reduce the contact resistance with the curved plates 26a and 26b, a needle roller bearing 31a is provided at a position where the curved plates 26a and 26b come into contact with the inner wall surface of the through hole 30a.

  The bearing 37 in this embodiment includes an inner ring 37a as a non-rotating side race ring whose inner diameter surface is fixed to the casing 22, and an outer ring 37b as a rotation side race ring whose outer diameter surface abuts on the inner pin 31; A deep groove ball bearing comprising a plurality of balls 37c as rolling elements disposed between an inner ring 37a and an outer ring 37b. The outer diameter surface of the outer ring 37b and the outer diameter surface of the retaining portion 31b are in contact with each other.

  On the other hand, the through hole 30a is provided at a position corresponding to each of the plurality of inner pins 31, and the inner diameter dimension of the through hole 30a is predetermined from the outer diameter dimension of the inner pin 31 (the maximum outer diameter including the needle roller bearing 31a). The minute is set.

  The wheel hub bearing portion C includes a wheel hub 32 fixedly connected to the wheel-side rotating member 28 and a wheel hub bearing 33 that holds the wheel hub 32 rotatably with respect to the casing 22. The wheel hub 32 has a cylindrical hollow portion 32a and a flange portion 32b. The drive wheel 14 (not shown) is fixedly connected to the flange portion 32b by a bolt 32c. In addition, a sealing member 32d is provided at the opening of the hollow portion 32a in order to prevent dust from entering the inside of the in-wheel motor drive device 21.

  The wheel hub bearing 33 is a double-row angular ball bearing that employs balls 33e as rolling elements. As the raceway surfaces of the balls 33e, a first outer raceway surface 33a (right side in the figure) and a second outer raceway surface 33b (left side in the figure) are provided on the inner diameter surface of the outer member 22a. A first inner raceway surface 33c facing the surface 33a is provided on the outer diameter surface of the inner member 38, and a second inner raceway surface 33d facing the second outer raceway surface 33b is provided on the outer diameter surface of the wheel hub 32, respectively. Yes. A plurality of balls 33e are arranged between the first outer raceway surface 33a and the first inner raceway surface 33c and between the second outer raceway surface 33b and the second inner raceway surface 33d. The wheel hub bearing 33 includes a retainer 33f that holds the left and right rows of balls 33e, and a sealing member 33g that prevents leakage of a lubricant such as grease enclosed in the bearing and dust from the outside. Including.

  The inward member 38 is a substantially cylindrical member having a hollow portion 38a, is fitted into the hollow portion 32a of the wheel hub 32, and receives the shaft portion 28b of the wheel-side rotating member 28 in the hollow portion 38a. The wheel hub 32 and the inward member 38 are fixed by diameter expansion caulking. “Diameter caulking” refers to a caulking jig (not shown) having an outer diameter slightly larger than the inner diameter of the hollow portion 38a of the inner member 38 in a state where the in-wheel motor driving device 21 is fixed. The inner member 38 and the wheel hub 32 are plastically coupled at the plastic coupling portion 40 by being press-fitted into 38a. By fixing and connecting the inner member 38 and the wheel hub 32 by the above method, the coupling strength can be greatly increased as compared with the case of fixing by fitting. Thereby, the wheel hub 32 can be stably held.

  On the other hand, the wheel side rotation member 28 and the inward member 38 are serrated and fitted in the fitting portion 28c. Specifically, on the inner diameter surface of the inward member 38, crests extending in the axial direction are arranged at equal intervals in the circumferential direction, and troughs are formed between adjacent crests. Similarly, a trough that receives the crest of the inner member 38 and a crest corresponding to the trough of the inner member 38 are formed on the outer diameter surface of the shaft portion 28 b of the wheel-side rotating member 28. And both are fitted so that the peak part of the wheel side rotation member 28 and the peak part of the inward member 38 may mesh.

  With the above configuration, the rotation of the wheel side rotation member 28 can be reliably transmitted to the wheel hub 32. In the gap portion 28d (the right side of the fitting portion 28c in the figure) where the crests and troughs of the wheel side rotation member 28 and the inward member 38 are not formed, the wheel side rotation member 28 and the inward member 38 A gap in the radial direction corresponding to the height of the peak is formed between the two. In this embodiment, the fitting portion 28c is disposed on the wheel hub bearing C side, and the gap portion 28d is disposed on the speed reducing portion B side.

  By securing a predetermined amount of this gap, the inner member 38 does not come into contact with the wheel-side rotating member 28 even if the wheel hub 32 is tilted, and the tilt of the wheel hub 32 is prevented from being transmitted to the wheel-side rotating member 28. Can do. However, if the radial gap formed in the gap 28d is too large, the peaks formed in the wheel-side rotating member 28 and the inward member 38 may be damaged, so that sufficient strength can be secured in the peaks. The gap amount is determined within the range.

  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 constituted by a permanent magnet or a direct current electromagnet rotates. At this time, the rotor 24 rotates at a higher speed as a higher frequency voltage is applied to the coil.

  Thereby, when the motor side rotation member 25 connected to the rotor 24 rotates, the curved plates 26 a and 26 b revolve around the rotation axis of the motor side rotation member 25. At this time, the outer pin 27 engages with the curved waveform of the curved plates 26 a and 26 b to cause the curved plates 26 a and 26 b to rotate in the direction opposite to the rotation of the motor-side rotating member 25.

  The inner pin 31 inserted through the through hole 30a comes into contact with the inner 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, but only the rotational motion of the curved plates 26 a and 26 b is transmitted to the wheel hub bearing portion C via the wheel-side rotating member 28.

  At this time, since the rotation of the motor-side rotating member 25 is decelerated by the speed reducing portion B and transmitted to the wheel-side rotating member 28, it is necessary for the drive wheel 14 even when the low torque, high rotation type motor portion A is adopted. It is possible to transmit an appropriate torque.

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, since Z _A = 12 and Z _B = 11, the reduction ratio is 1/11, and a very large reduction ratio can be obtained.

  In this way, by adopting the speed reduction unit B that can obtain a large speed reduction ratio without using a multi-stage configuration, the in-wheel motor drive device 21 having a compact and high speed reduction ratio can be obtained. Further, by providing the needle roller bearings 27a and 31a at positions where they contact the curved plates 26a and 26b of the outer pin 27 and the inner pin 31, the contact resistance is reduced, so that the transmission efficiency of the speed reduction portion B is improved. .

  Further, the inner pin 31 is supported at both ends by the casing 22 and the wheel-side rotating member 28, and the wheel-side rotating member 28 and the inner member 38 are serrated and fitted, whereby the inclination of the wheel hub 32 is rotated on the wheel side. The structure is difficult to be transmitted to the member 28. As a result, it is possible to obtain a highly reliable in-wheel motor drive device 21 in which troubles such as rotation failure and breakage of the speed reduction unit B are prevented.

  By employing the in-wheel motor drive device 21 according to the above embodiment in the electric vehicle 11, the unsprung weight can be suppressed. As a result, the electric vehicle 11 having excellent running stability can be obtained.

  Since the curved plates 26a and 26b revolve at high speed while engaging with the outer pin 27, a large radial load is applied to the rolling bearing 39 that supports the curved plates 26a and 26b. However, there is a possibility that the rolling bearing 39 having a sufficient load capacity cannot be arranged in a limited space inside the deceleration part B. In addition, this problem becomes more conspicuous with the recent demand for a compact electric vehicle 11.

  Therefore, the outer race 39b can be omitted by providing the outer raceway surface of the rolling bearing 39 on the inner wall surface of the through hole 30b of the curved plates 26a, 26b. As a result, the gap between the inner raceway surface and the outer raceway surface is increased, so that it is possible to employ balls 39c having a large diameter or increase the number of balls 39c. As a result, the load capacity can be improved without changing the overall size of the rolling bearing 39, so that an in-wheel motor drive device having excellent durability and high reliability can be obtained. In addition, it can be expected to reduce the product cost by reducing the number of parts.

  In the above-described embodiment, two curved plates 26a and 26b of the deceleration portion B are provided with 180 ° phase shifts. However, the number of curved plates can be arbitrarily set. For example, three curved plates are provided. In such a case, it is preferable to change the 120 ° phase.

  In addition, although description of the action | operation in said embodiment was performed paying attention to rotation of each member, the motive power containing a torque is actually transmitted from the motor part A to a driving wheel. Therefore, the power decelerated as described above is converted into high torque.

  Further, in the description of the operation in the above embodiment, power is supplied to the motor unit A to drive the motor unit A, and the power from the motor unit A is transmitted to the drive wheels 14, but on the contrary, When the vehicle decelerates or goes down a hill, the power from the drive wheel 14 side is converted into high-rotation and low-torque rotation by the deceleration unit B and transmitted to the motor unit A, and the motor unit A generates power. May be. Furthermore, the electric power generated here may be stored in a battery and used later for driving the motor unit A or for operating other electric devices provided in the vehicle.

  Further, a brake can be added to the configuration of the above embodiment. For example, in the configuration of FIG. 1, the casing 22 is extended in the axial direction to form a space on the right side of the rotor 24 in the drawing, the rotating member that rotates integrally with the rotor 24, and the casing 22 is non-rotatable and axial. A parking brake may be provided in which a movable piston and a cylinder for operating the piston are disposed, and the rotor 24 is locked by fitting the piston and the rotating member when the vehicle is stopped.

  Alternatively, it may be a disc brake in which a flange formed on a part of a rotating member that rotates integrally with the rotor 24 and a friction plate installed on the casing 22 side are sandwiched by a cylinder installed on the casing 22 side. Furthermore, a drum brake can be used in which a drum is formed on a part of the rotating member, a brake shoe is fixed to the casing 22 side, and the rotating member is locked by friction engagement and self-engagement.

  In the above-described embodiment, the example in which the other end portion of the inner pin 31 is in contact with and supported by the outer diameter surface of the bearing 37 fixed to the casing 22 has been described. The diameter surface may be fixed to the casing 22 and the other end portion of the inner pin 31 may be supported by the inner diameter surface of the inner ring 37a. The effect of the present invention can also be obtained by omitting the bearing 37 and providing the casing 22 with a recess that can be supported in a state in which the revolution of the inner pin 31 is allowed.

  In the above embodiment, the wheel side rotation member 28 and the inner member 38 are serrated and fitted. However, the present invention is not limited to this, and any connection structure can be applied. . For example, the wheel-side rotating member 28 and the inner member 38 may be spline-fitted, or a joint may be disposed between the wheel-side rotating member 28 and the inner member 38.

  In the above embodiment, the example in which the wheel hub 32 and the inner member 38 are fixedly connected by expanding and caulking is shown. However, the present invention is not limited to this, and the wheel hub 32 and the inner member 38 can be fixedly connected by any method. .

  Further, in the above embodiment, an example in which a deep groove ball bearing is adopted as the bearing 37 that supports the inner pin 31 is shown. However, the present invention is not limited to this. For example, a plain bearing, a cylindrical roller bearing, a tapered roller bearing, a needle Whether the rolling element is a roller or a ball, whether it is a plain bearing, a self-aligning roller bearing, a deep groove ball bearing, an angular contact ball bearing, a four-point contact ball bearing, etc. Any bearing can be applied regardless of whether it is a double row or a single row. Similarly, any type of bearing can be adopted for bearings arranged in other locations.

  In each of the above embodiments, an example in which an axial gap motor is adopted as the motor unit A has been described. However, the present invention is not limited to this, and a motor having an arbitrary configuration can be applied. For example, it may be a radial gap motor including a stator fixed to the casing and a rotor disposed at a position facing each other with a radial gap inside the stator.

  Furthermore, although the electric vehicle 11 shown in FIG. 4 showed the example which used the rear wheel 14 as the driving wheel, it is not restricted to this, The front wheel 13 may be used as a driving wheel and may be a four-wheel driving vehicle. . In the present specification, “electric vehicle” is a concept including all vehicles that obtain driving force from electric power, and should be understood as including, for example, a hybrid vehicle.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

It is a schematic sectional drawing of the in-wheel motor drive device concerning one Embodiment of this invention. It is sectional drawing in II-II of FIG. It is an enlarged view of the eccentric part periphery of FIG. It is a top view of the electric vehicle which has the in-wheel motor drive device of FIG. FIG. 5 is a rear sectional view of the electric vehicle of FIG. 4. It is a figure which shows the conventional in-wheel motor drive device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 Electric vehicle, 12 Chassis, 12a Wheel housing, 12b Suspension device, 13 Front wheel, 14 Rear wheel, 21,101 In-wheel motor drive device, 22,102 Casing, 22a Outer member, 23 Stator, 24 Rotor, 24a, 28a 32b Flange part, 24b, 32a, 38a Hollow part, 28b Shaft part, 28c Fitting part, 28d Gap part, 25, 106 Motor side rotating member, 25a, 25b, 106a, 106b Eccentric part, 26a, 26b, 107a, 107b Curved plate, 27, 108 Outer pin, 27a, 31a Needle roller bearing, 28, 52, 110 Wheel side rotating member, 29 Counterweight, 30a, 30b Through hole, 31, 109 Inner pin, 32d, 33g, 34, 36 sealing member, 33 wheel hub bearing, 33a first outer Raceway surface, 33b second outer raceway surface, 33c first inner raceway surface, 33d second inner raceway surface, 33e, 37c, 39c ball, 33f cage, 34a, 34b, 36a, 36b, 37, 39 rolling bearing, 37a , 39a Inner ring, 37b, 39b Outer ring, 38 Inner member, 40 Plastic coupling part.

Claims (3)

A casing,
A motor unit for rotationally driving the motor side rotating member;
A speed reducer that decelerates the rotation of the motor side rotating member and transmits it to the wheel side rotating member;
A wheel hub fixedly connected to the wheel side rotating member,
The motor side rotating member further has an eccentric part,
The deceleration part is
A revolving member that is rotatably held by the eccentric part and performs a revolving motion around its rotational axis as the motor-side rotating member rotates.
An outer peripheral engagement member that engages with an outer peripheral portion of the revolution member and causes the revolution member to rotate.
An inner pin that revolves around the rotation axis of the wheel-side rotating member, and a through-hole that penetrates in a thickness direction of the revolving member by a predetermined amount larger than an outer diameter of the inner pin and receives the inner pin A rotation conversion mechanism that converts the rotation of the revolving member into a rotation around the rotation axis of the motor side rotation member and transmits the rotation to the wheel side rotation member;
An in-wheel motor drive device in which one end of the inner pin is fixed to the wheel-side rotating member, and the other end is held in a state in which revolving is allowed by the casing.   The in-wheel motor drive device of Claim 1 with which the bearing is arrange | positioned between the other side edge part of the said inner pin, and the said casing. The bearing is
An inner ring as a non-rotating side bearing ring whose inner diameter surface is fixed to the casing;
An outer ring as a rotation-side raceway whose outer diameter surface abuts on the inner pin;
The in-wheel motor drive device of Claim 2 which is a rolling bearing provided with the some rolling element arrange | positioned between the said inner ring | wheel and the said outer ring | wheel.

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