JP2010249208A - In-wheel motor drive unit and motor drive device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in-wheel motor drive unit capable of eliminating dynamic unbalance as well as static unbalance. <P>SOLUTION: A first eccentric member 25I and a third eccentric member 25n are eccentrically arranged in the same phase. A second eccentric member 25m arranged between these first eccentric member 25I and the third eccentric member 25n is eccentrically arranged in a phase different at 180 degrees from these members. Thus, the optimized weight balance can eliminate the dynamic unbalance as well as the static unbalance. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an in-wheel motor drive device and a vehicle motor drive device including a cycloid reduction mechanism, and more particularly to the arrangement of rotating elements of a cycloid reduction mechanism.

  A conventional in-wheel motor drive device is described in, for example, Japanese Patent Application Laid-Open No. 2006-258289 (Patent Document 1). The in-wheel motor drive device of Patent Document 1 includes a drive motor, a speed reducer that receives a driving force from the drive motor and decelerates the number of rotations to output to the wheel side, and a wheel coupled to the output shaft of the speed reducer. The hub members are arranged coaxially and in series. Since this speed reducer is a cycloid speed reduction mechanism, 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.

  Further, the cycloid reduction mechanism of the in-wheel motor drive device has two curved plates that are spaced apart from each other in the rotation axis direction. These curved plates correspond to revolving members, and rotate at a low rotational speed while revolving at a high rotational speed. Therefore, it is desirable to attach them in consideration of balance. Therefore, the two curved plates described in Patent Document 1 are attached to eccentric positions that differ by 180 degrees in the circumferential direction around the rotation axis, and are arranged so that the balance is balanced.

JP 2006-258289 A

  In the conventional cycloid reduction mechanism, since the two curved plates are arranged so that the phases of the two curved plates are different by 180 degrees, the centrifugal force in the radial direction can be balanced. This state is called static balance. However, the present inventor has found that there is a further improvement in the conventional in-wheel motor drive device. That is, although the static imbalance is eliminated, the moment around the axis perpendicular to the rotation axis does not become zero, so that the dynamic imbalance is present. This dynamic imbalance increases the vibration of the cycloid reduction mechanism, and this vibration becomes more prominent as the motor speed increases.

  In view of the above circumstances, an object of the present invention is to provide an in-wheel motor drive device and a vehicle motor drive device that can eliminate static imbalance as well as dynamic imbalance.

  For this purpose, an in-wheel motor driving device according to the present invention includes a motor unit that rotationally drives a 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. A wheel hub fixedly connected to the member, and the speed reducer is decentered from the rotation axis of the motor side rotating member and is coupled to the motor side rotating member, and the inner periphery is decentered from three. Three revolving members which are attached to the outer periphery of the member so as to be relatively rotatable and perform a revolving motion around the rotation axis along with the rotation of the motor side rotating member, and the revolving member engaged with the outer peripheral portion of the revolving member It is premised on having an outer peripheral engagement member that causes the rotation movement of the outer periphery and an inner engagement member that is coupled to the wheel-side rotation member and extracts the rotation movement of the revolution member.

  Under this premise, the three revolving members are arranged on the first revolving member, the second revolving member arranged on the one axial side of the first revolving member, and further on the one axial side of the second revolving member. And a third revolving member. The three eccentric members support the first revolving member so as to be relatively rotatable, and support the first eccentric member disposed eccentrically from the rotation axis in the direction perpendicular to the axis, and the second revolving member so as to be relatively rotatable. A second eccentric member disposed eccentrically at a circumferential position 180 degrees different from the first eccentric member on one axial direction side of the first eccentric member; and a third revolving member that is relatively rotatable and further supports the second eccentric member. And a third eccentric member arranged eccentrically at a circumferential position that is 180 degrees different from the second eccentric member on one side in the axial direction.

The sum of weights of the first revolving member and the first eccentric member is M _Sl , and the eccentric distance from the rotation axis to the center of gravity of the first revolving member and the first eccentric member is E _Sl, and the second revolving member and the second eccentric member M _Sm , the eccentric distance from the rotation axis to the center of gravity of the second revolving member and the second eccentric member is E _Sm, and the weight sum of the third revolving member and the third eccentric member is M _Sn , 3 an eccentric distance to the center of gravity of the revolving member, and the third eccentric member as E _Sn,
M _S1 E _S1 + M _Sn E _Sn = M _Sm E _Sm is satisfied.

Furthermore, each revolution member and the eccentric member are installed so that the centers of gravity of the revolution member and the eccentric member coincide with each other, the center of gravity of the first revolution member and the first eccentric member, the center of gravity of the second revolution member and the second eccentric member, L _Slm is the axial direction distance of L 2, and L _Smn is the axial distance between the center of gravity of the second revolving member and the second eccentric member and the center of gravity of the third revolving member and the third eccentric member.
To satisfy the _{M Sl E Sl L Slm = M} Sn E Sn L Smn.

  According to the present invention, the first eccentric member and the third eccentric member are eccentrically arranged in the same phase, and the second eccentric member arranged between the first eccentric member and the third eccentric member is 180 with them. It is eccentrically arranged at different phases, and the weight balance is optimal. Accordingly, static imbalance can be eliminated and dynamic imbalance can also be eliminated.

  Note that the weight sum here is understood to include components of the rolling bearing, such as inner and outer rings, rolling elements, and cages, when a rolling bearing is provided between each revolution member and each eccentric member. I want. This is because such a rolling bearing is also a component of each revolution member or each eccentric member.

Here, preferably, M _S1 = M _Sn and 2M _S1 = M _Sm are satisfied. According to this embodiment, while realizing _{E Sl + E Sn = 2E Sm} , E Sl L Slm = it is possible to realize the _{E Sn} L _Smn, the same parts, the first revolving member and a first eccentric member And can be used for the third revolving member and the third eccentric member. Therefore, it is possible to provide an in-wheel motor drive device that is advantageous in terms of manufacturing cost.

More preferably, E _S1 = E _Sn is satisfied. According to this embodiment, the eccentric distance between the revolution member and the eccentric member can be set to E _S1 = E _Sm = E _Sn, and the axis perpendicular direction dimension of the speed reduction portion can be made uniform.

  In the present invention, the sum of the weights of the revolution members and the eccentric members satisfies the above-described formulas in the first to third, respectively, and the centers of gravity of the revolution members and the eccentric members are the same in the first to third, respectively. The above formula is satisfied, and the weight, eccentric distance, and axial distance of the first to third eccentric members themselves are not limited.

Thus, although this invention is not limited to 1 Example, 1st-3rd revolution member itself may be comprised similarly to the type | formula mentioned above. That is, the weight of the first revolution member is M _Al , the eccentric distance from the rotation axis to the center of gravity of the first revolution member is E _Al , the weight of the second revolution member is M _Am , and from the rotation axis to the center of gravity of the second revolution member the eccentricity and E _Am of the weight of the third revolving member M _an, the eccentricity from the axis of rotation to the center of gravity of the third revolving member as E _an,
Satisfying _{M Al E Al + M An E} An = M Am E Am.

Further, the axial distance between the center of gravity of the first revolution member and the center of gravity of the second revolution member is L _Alm , and the axial distance between the center of gravity of the second revolution member and the center of gravity of the third revolution member is L _Amn ,
M _Al E _Al L _Alm = M _An E _An L _Amn is satisfied.

  According to this embodiment, static balance and dynamic balance can be suitably realized.

Here, preferably, M _Al = M _An and 2M _Al = M _Am are satisfied. According to such an embodiment, E _Al + E _An = 2E _Am and E _Al L _Alm = E _An L _Amn can be realized, and the same component can be used for the first revolution member and the third revolution. Can be used for members. Therefore, it is possible to provide an in-wheel motor drive device that is advantageous in terms of manufacturing cost.

  More preferably, the axial thickness of the second revolution member is twice the axial thickness of the first revolution member. According to such an embodiment, the first revolution member, the second revolution member, and the third revolution member having the same outer diameter and inner diameter can be formed of a common material, which is advantageous in terms of manufacturing process and cost.

Preferably, E _Al = E _An is satisfied. According to such an embodiment, the eccentric distance of the revolution member can be set to E _Al = E _Am = E _An, and the axial perpendicular direction dimension of the speed reduction portion can be made uniform.

In the present invention, the eccentric member itself that rotatably supports the revolution member is not particularly limited, but the first to third eccentric members themselves may be configured in the same manner as the above-described formula. That is, the weight of the first eccentric member is M _B1 , the eccentric distance from the rotation axis to the center of gravity of the first eccentric member is E _Bl , the weight of the second eccentric member is M _Bm , and from the rotation axis to the center of gravity of the second eccentric member E _Bm , the weight of the third eccentric member is M _Bn , and the eccentric distance from the rotation axis to the center of gravity of the third eccentric member is E _Bn .
M _B1 E _B1 + M _Bn E _Bn = M _Bm E _Bm is satisfied.

Further, an axial distance between the center of gravity of the centroid and the second eccentric member of the first eccentric member and L _Blm, the axial distance between the center of gravity of the centroid and the third eccentric members of the second eccentric member as L _Bmn,
To satisfy the _{M Bl E Bl L Blm = M} Bn E Bn L Bmn.

  According to this embodiment, static balance and dynamic balance can be suitably realized.

Here, preferably, M _B1 = M _Bn and 2M _B1 = M _Bm are satisfied. According to this embodiment, while realizing _{E Bl + E Bn = 2E Bm} , it becomes possible to realize the _{E Bl L Blm = E Bn L} Bmn, the same parts, and a first eccentric member, a third eccentric Can be used for members. Therefore, it is possible to provide an in-wheel motor drive device that is advantageous in terms of manufacturing cost.

  More preferably, the axial thickness of the second eccentric member is twice the axial thickness of the first eccentric member. According to such an embodiment, the first eccentric member, the second eccentric member, and the third eccentric member having the same outer diameter and inner diameter can be formed of a common material, which is advantageous in terms of manufacturing process and cost.

Preferably, E _Bl = E _Bn is satisfied. According to such an embodiment, the eccentric distance of the eccentric member can be set to E _B1 = E _Bm = E _Bn, and the axis perpendicular direction dimension of the speed reduction portion can be made uniform.

  Preferably, the first eccentric member rotatably supports the first revolution member by a ball bearing, the second eccentric member rotatably supports the second revolution member by a roller bearing, and the third eccentric member is a third revolution member. Is supported rotatably by ball bearings. According to such an embodiment, the first and third revolving members are rotatably supported by the ball bearing having a small load capacity, and the second revolving member is rotatably supported by the roller bearing having a large load capacity. It becomes possible to favorably support the second revolution member having the largest bearing load among the three revolution members, and the durability of the speed reduction portion is improved.

  The vehicle motor drive device according to the present invention includes a motor unit that rotationally drives the motor side rotation member, a speed reduction unit that decelerates the rotation of the motor side rotation member and transmits the rotation to the wheel side rotation member, and the rotation of the wheel side rotation member. And a speed reducer that includes three disc-shaped eccentric members that are eccentric from the rotational axis of the motor-side rotating member and coupled to the motor-side rotating member, and an inner circumference of 3 Three reciprocating members which are attached to the outer peripheries of the individual eccentric members so as to rotate relative to each other and perform a revolving motion around the rotation axis along with the rotation of the motor side rotating member, and the outer peripheral portion of the revolving member. It is assumed that the outer peripheral engagement member that causes the rotation motion of the revolution member and the inner engagement member that couples with the wheel-side rotation member and extracts the rotation motion of the revolution member.

  Under this premise, the three revolving members are arranged on the first revolving member, the second revolving member arranged on the one axial side of the first revolving member, and further on the one axial side of the second revolving member. And a third revolving member. The three eccentric members support the first revolving member so as to be relatively rotatable, and support the first eccentric member disposed eccentrically from the rotation axis in the direction perpendicular to the axis, and the second revolving member so as to be relatively rotatable. A second eccentric member disposed eccentrically at a circumferential position 180 degrees different from the first eccentric member on one axial direction side of the first eccentric member; and a third revolving member that is relatively rotatable and further supports the second eccentric member. And a third eccentric member arranged eccentrically at a circumferential position that is 180 degrees different from the second eccentric member on one side in the axial direction.

The sum of weights of the first revolving member and the first eccentric member is M _Sl , and the eccentric distance from the rotation axis to the center of gravity of the first revolving member and the first eccentric member is E _Sl, and the second revolving member and the second eccentric member M _Sm , the eccentric distance from the rotation axis to the center of gravity of the second revolving member and the second eccentric member is E _Sm, and the weight sum of the third revolving member and the third eccentric member is M _Sn , 3 an eccentric distance to the center of gravity of the revolving member, and the third eccentric member as E _Sn,
M _S1 E _S1 + M _Sn E _Sn = M _Sm E _Sm is satisfied.

Furthermore, each revolution member and the eccentric member are installed so that the centers of gravity of the revolution member and the eccentric member coincide with each other, the center of gravity of the first revolution member and the first eccentric member, the center of gravity of the second revolution member and the second eccentric member, L _Slm is the axial direction distance of L 2, and L _Smn is the axial distance between the center of gravity of the second revolving member and the second eccentric member and the center of gravity of the third revolving member and the third eccentric member.
To satisfy the _{M Sl E Sl L Slm = M} Sn E Sn L Smn.

  According to the present invention, the first eccentric member and the third eccentric member are eccentrically arranged in the same phase, and the second eccentric member arranged between the first eccentric member and the third eccentric member is 180 with them. It is eccentrically arranged at different phases, and the weight balance is optimal. Accordingly, static imbalance can be eliminated and dynamic imbalance can also be eliminated.

  Note that the weight sum here is understood to include components of the rolling bearing, such as inner and outer rings, rolling elements, and cages, when a rolling bearing is provided between each revolution member and each eccentric member. I want. This is because such a rolling bearing is also a component of each revolution member or each eccentric member.

  As described above, in the present invention, the three eccentric members are 180 degrees different from the first eccentric member arranged eccentrically in the direction perpendicular to the axis from the rotation axis, and the first eccentric member on one side in the axial direction of the first revolving member. Because it includes a second eccentric member arranged eccentrically at the circumferential position, and a third eccentric member arranged eccentrically at the same circumferential position as the first revolving member on one axial direction side of the second eccentric member. In addition, it is possible to realize static balance and dynamic balance of the speed reduction unit. As a result, it is possible to prevent vibration of the speed reduction portion, and it is possible to extend the life of the in-wheel motor drive device and the vehicle motor drive device.

It is a longitudinal cross-sectional view which shows the in-wheel motor drive device which becomes one Example of this invention. It is sectional drawing in II-II of FIG. It is a longitudinal cross-sectional view which expands and shows the positional relationship of the eccentric member and curved board of the Example. It is explanatory drawing which shows typically the positional relationship which looked at the eccentric member of the Example from the rotating shaft direction. It is a top view which shows the arrangement layout of the in-wheel motor drive device of the Example. It is an expanded sectional view showing the motor drive device for vehicles which becomes other examples of the present invention. It is a top view which shows the arrangement layout of the vehicle motor drive device of 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. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a longitudinal sectional view showing an eccentric member and a curved plate extracted from the embodiment. FIG. 4 is an explanatory diagram schematically showing the positional relationship of the eccentric member of the same embodiment as seen from the rotational axis direction. FIG. 5 is a plan view showing an arrangement layout of the in-wheel motor drive device of the embodiment.

  The in-wheel motor drive device 21 includes a motor unit A as a motor drive device that generates a driving force, a deceleration unit B that decelerates and outputs the rotation of the motor unit A, and a drive wheel (not shown) that outputs from the deceleration unit B And a wheel hub bearing portion C for transmitting to the wheel. The motor part A is housed in a motor casing 22a, a pump casing 22p, and a motor cover 22t that form the outer part of the motor part, and the speed reducing part B is housed in a speed reducing part casing 22b that forms the outer part of the speed reducing part. C is rotatably supported by a bearing section casing 22c fixed to the speed reduction section casing 22b, and is mounted, for example, in a wheel housing of an electric vehicle. Or it is attached to the bogie of a railway vehicle. The motor casing 22a, the pump casing 22p, the motor cover 22t, the speed reduction portion casing 22b, and the bearing portion casing 22c are connected to each other to form one casing 22.

  The motor part A includes a stator 23 fixed to the inner periphery of a cylindrical motor casing 22a, a rotor 24 disposed at a position facing the inside of the stator 23 via a gap opened in the radial direction, It is a radial gap motor provided with a rotating shaft 35 that is fixedly connected to the inside and rotates integrally with the rotor 24.

  The end of the rotating shaft 35 is rotatably supported by the motor cover 22t via the rolling bearing 63. The opposite end of the rotating shaft 35 is rotatably supported by the pump casing 22p via the rolling bearing 62 and is coupled to one end of the speed reducing portion input shaft 25. The motor cover 22t is a disk-shaped member that closes the opening at one end of the motor casing 22a, and is an end portion of the motor portion A and also an end portion of the in-wheel motor drive device 21. The pump casing 22p is a disk-shaped member that closes the opening at the other end of the motor casing 22a, and includes an oil pump 51 described later.

  The speed reducer B includes a speed reducer input shaft 25 coupled to the rotation shaft 35, a first eccentric member 25l, a second eccentric member 25m, and a third eccentric member 25n coupled to the speed reducer input shaft 25, and these first eccentric members. The first curved plate 26l, the second curved plate 26m, and the third curved plate 26n as revolving members that are rotatably held by the members to the third eccentric members 25l to 25n, and the curved plates 26l, 26m, and 26n, respectively. As an inner engagement member that extracts a plurality of outer pins 27 as outer peripheral engagement members that engage with the outer peripheral portion, a speed reduction portion casing 22b that supports both ends of the outer pin 27, and curvilinear plates 26l, 26m, and 26n. The inner pin 31, the wheel-side rotating member 28 coupled to the inner pin 31, and the curved plates 26l and 26m are attached to the gaps between the curved plates 26l and 26m and contact the end surfaces of the curved plates 26l and 26m. A center collar 29 that prevents the curved plate 26m, 26n from contacting the end surfaces of the curved plate 26m, 26n to prevent the curved plate from tilting, and the inner pin 31 to bend. And a reinforcing member 61 for preventing.

  The speed reduction part input shaft 25 has a constant outer diameter, that is, a thickness, and does not have an eccentric part. One end of the speed reduction part input shaft 25 on the side far from the motor part A is rotatably supported by an end part of a wheel side rotation member 28 described later via a bearing 64. Further, the other end of the speed reducer input shaft 25 on the side close to the motor part A is coupled to one end of the rotating shaft 35. Between these both ends, eccentric members 25l, 25m, and 25n are fitted and fixed on the outer periphery of the speed reduction unit input shaft 25 in a direction perpendicular to the rotation axis O. The three disc-shaped eccentric members 251, 25 m, 25 n are provided with a 180 ° phase change in the circumferential direction around the rotation axis O in order to cancel out vibrations generated by centrifugal force due to the eccentric motion.

  That is, the first eccentric member 251 disposed on the side close to the rotor 24 and the third eccentric member 25n disposed on the side far from the rotor 24 are provided in the same phase. On the other hand, the second eccentric member 25m disposed between the first eccentric member 25l and the third eccentric member 25n is provided with a phase difference of 180 degrees with respect to the first eccentric member 25l and the third eccentric member 25n. ing. The 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.

  Referring to FIG. 2, a second curved plate 26m is concentrically attached to the outer periphery of the second eccentric member 25m. The second curved plate 26m has a plurality of curved concave portions that are formed of a trochoidal curve such as epitrochoid on the outer peripheral portion and are recessed in the radial direction, and these curved concave portions engage with an outer pin 27 described later. The second curved plate 26m has a plurality of through holes 30a and 30b penetrating from one end face to the other end face.

  The center Xm of the disk-shaped second eccentric member 25m is also the rotational axis of the curved plate 26m, and is provided at a position eccentric from the axis O. In FIG. 2, an axial oil passage 57 described later extends along the rotation axis O.

  A plurality of through holes 30a are provided at equal intervals on the circumference centered on the rotation axis Xm of the second curved plate 26m, and receive the inner pins 31 respectively. Needle roller bearings 31a are provided on the outer periphery of the inner pin 31, so that the outer periphery of the inner pin 31 is in rolling contact with the hole wall surface of the through hole 30a. Further, the through hole 30b is provided at the center Xm of the second curved plate 26m and becomes the inner periphery of the second curved plate 26m. A rolling bearing 41 is interposed between the inner peripheral surface of the through hole 30b and the outer peripheral surface of the second eccentric member 25m. The second curved plate 26m is attached to the outer periphery of the second eccentric member 25m via the rolling bearing 41 so as to be relatively rotatable.

  The rolling bearing 41 includes an inner ring member 42 that fits on the outer peripheral surface of the second eccentric member 25m, a plurality of rollers 44, and a cage (not shown) that holds the interval between the rollers 44 adjacent in the circumferential direction. The cylindrical roller bearing has a hole wall surface of the through hole 30b as an outer raceway surface. Alternatively, it may be a deep groove ball bearing. The inner ring member 42 further includes a pair of flanges facing each other with the inner raceway surface 42a of the inner ring member 42 on which the roller 44 rolls in the direction of the axis O, and holds the rollers 44 between the pair of flanges. The first curved plate 26l and the third curved plate 26n are also rotatably supported by the rolling bearing 41, and specifically supported by a deep groove ball bearing.

  Returning to FIG. 1, the plurality of inner pins 31 extend in parallel with the axis O, and are commonly supported by the wheel-side rotating member 28 at the base end on the side far from the motor part A. The wheel-side rotation member 28 includes a shaft portion 28 b extending along the axis O, and a flange portion 28 a that is formed at the end portion of the shaft portion 28 b and is coupled to the base end of the inner pin 31. Holes for fixing the inner pins 31 at equal intervals on the circumference centering on the rotation axis O of the wheel side rotation member 28 are formed in the end face of the flange portion 28a. A wheel hub 32 of a wheel hub bearing portion C described later is fixed to the outer peripheral surface of the shaft portion 28b.

  A reinforcing member 61 is provided at the tip of the inner pin 31 on the side away from the flange portion 28a. The reinforcing member 61 includes a flange-shaped annular portion 61b coupled to the tips of the plurality of inner pins 31, and a cylindrical portion 61c extending from the inner diameter portion of the annular portion 61b to the motor portion A in the direction of the axis O. Since the load applied to some of the inner pins 31 from the three curved plates 26l, 26m, and 26n is supported by all the inner pins 31 via the annular portion 61b, the stress acting on the inner pins 31 is reduced. And durability can be improved. The tip of the cylindrical portion 61 c is drivingly coupled to the oil pump 51.

  A plurality of outer pins 27 that engage with the outer peripheries of the curved plates 26l, 26m, and 26n are provided at equal intervals on a circumferential track centering on the rotation axis O of the speed reducing portion input shaft 25. When the curved plates 26l, 26m, and 26n are revolved by the eccentric members 25l, 25m, and 25n, the curved concave portions on the outer periphery of the curved plates 26l, 26m, and 26n and the outer pin 27 are engaged with each other. Rotational motion is generated at 26l, 26m, and 26n.

  The outer pin 27 disposed inside the speed reduction part casing 22b may be directly held by the speed reduction part casing 22b, but preferably is an outer pin holding part fitted and fixed to the inner wall of the speed reduction part casing 22b. 45. More specifically, both end portions in the axial direction of the outer pin 27 are rotatably supported by needle roller bearings 27 a attached to the outer pin holding portion 45. Thus, by attaching the outer pin 27 to the outer pin holding portion 45 so as to be rotatable, the contact resistance due to the engagement with the curved plates 26l, 26m, and 26n can be reduced.

  From the viewpoint of reducing the weight of the in-wheel motor drive device 21, the casing 22 is formed of a light metal such as an aluminum alloy or a magnesium alloy. On the other hand, it is desirable to form the outer pin holding part 45, which requires high strength, from carbon steel.

  The wheel hub bearing portion C includes a wheel hub 32 fixedly connected to the wheel-side rotating member 28, a wheel hub bearing 33 that rotatably holds the wheel hub 32, and a bearing portion casing 22c that supports the wheel hub bearing 33. Prepare. The wheel hub bearing 33 is a double-row angular ball bearing, and its outer ring is fitted and fixed to the inner periphery of the cylindrical bearing portion casing 22 c, and the inner ring is fitted and fixed to the outer peripheral surface of the wheel hub 32. The wheel hub 32 includes a cylindrical hollow portion 32a that receives the shaft portion 28b of the wheel-side rotating member 28, and a flange portion 32b that is formed at the end of the hollow portion 32a on the side farther from the speed reduction portion B in the axis O direction. A drive wheel road wheel (not shown) is connected and fixed to the flange portion 32b by a bolt 32c.

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

  For example, the motor unit A receives an electromagnetic force generated by supplying an alternating current to the stator 23, and the rotor 24 including a magnetic body or a permanent magnet rotates. Thereby, when the rotating shaft 35 connected to the rotor 24 rotates, the speed reducing portion input shaft 25 rotates together with the rotating shaft 35, and the eccentric members 25l, 25m, 25n coupled to the speed reducing portion input shaft 25 are centered on the axis O. Eccentric movement.

  Then, the curved plates 26l, 26m, and 26n revolve around the rotation axis O of the motor side rotation member. At this time, the outer pin 27 engages with the curved concave portions formed on the outer circumferences of the curved plates 26l, 26m, and 26n while being in rolling contact with the curved plates 26l, 26m, and 26n, which is opposite to the rotation of the motor side rotating member. Rotate in the direction.

  The outer periphery of the inner pin outer ring 31b inserted through the through hole 30a is sufficiently thinner than the inner diameter of the through hole 30a, and abuts against the hole wall surface of the through hole 30a as the curved plates 26l, 26m, and 26n rotate. As a result, the revolving motion of the curved plates 26 l, 26 m and 26 n is not transmitted to the inner pin 31, but only the rotational motion of the curved plates 26 l, 26 m and 26 n is transmitted to the wheel hub bearing portion C via the wheel side rotating member 28. .

At this time, the wheel-side rotating member 28 arranged coaxially with the axis O takes out the rotation of the curved plates 26l, 26m, and 26n as the output shaft of the speed reduction unit B. The reduction ratio of the reduction part B 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 26l, 26m, and 26n. 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. As a result, the rotation of the speed reduction unit input shaft 25 is decelerated by the speed reduction unit B and transmitted to the wheel side rotation member 28. Therefore, even when the low torque, high rotation type motor unit A is employed, it is necessary for the drive wheels. Torque can be transmitted.

  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, the frictional resistance is reduced by making the outer pin 27 rotatable with respect to the outer pin holding portion 45 and providing the needle roller bearing 31a at a position in contact with the curved plates 26l, 26m, 26n of the inner pin 31. Therefore, the transmission efficiency of the deceleration part B improves.

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

  In the present embodiment, an example is shown in which the inner pin 31 is fixed to the wheel-side rotating member 28 and the through hole 30a is provided in the curved plates 26l, 26m, and 26n. Without any limitation, the rotation of the speed reduction unit B can be arbitrarily configured to be transmitted to the wheel hub 32. For example, it may be a motion conversion mechanism composed of an inner pin fixed to a curved plate and a hole formed in the wheel side rotation member.

  The description of the operation in the present embodiment has been made by paying attention to the rotation of each member, but in reality, power including torque is transmitted from the motor unit A to the drive wheels. Therefore, the power decelerated as described above is converted into high torque.

  In the description of the operation in the present 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. When decelerating or going down a hill, the power from the driving wheel side may be 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 may generate power. . Furthermore, the electric power generated here may be stored in a battery, and the motor unit A may be driven later, or may be used for the operation of other electric devices provided in the vehicle.

  Next, the lubrication structure of the deceleration part B will be described in detail.

  A suction oil passage 52 provided in the pump casing 22p and extending in the vertical direction connects the suction port of the oil pump 51 and an oil reservoir 53 provided in the lower part of the speed reduction unit B. The discharge oil passage 54 provided in the pump casing 22p and extending in the vertical direction is connected to the discharge port of the oil pump 51 at the lower end and connected to one end of the cooling oil passage 55 provided in the motor casing 22a at the upper end. The cooling oil passage 55 intersects with a water jacket 65 provided in the motor casing 22a. The water jacket 65 includes a cooling water inlet 65i, a cooling water inlet / outlet 65o, and a cooling water passage 65w disposed around the motor portion A. The water jacket 65 functions as an oil cooler connected to the axial oil passage 57, and the cooling water flowing in from the cooling water inlet 65i cools the lubricating oil flowing through the motor section A and the cooling oil passage 55 in the course of flowing through the cooling water passage 65w. And flows out from the cooling water inlet / outlet 65o.

  The other end of the cooling oil passage 55 is connected to one end of a communication oil passage 56 provided in the motor cover 22t. The other end of the communication oil passage 56 extending in the radial direction is connected to an axial oil passage 57 provided in common inside the tubular rotating shaft 35 and the tubular speed reducing portion input shaft 25 coupled to each other. The axial oil passage 57 extends along the axis O so as to penetrate from the other end of the rotating shaft 35 pivotally supported by the motor cover 22t to one end of the speed reducing portion input shaft 25 pivotally supported by the bearing 64. The axial oil passage 57 is connected to a lubricating oil passage 58 extending from the axis O in the second eccentric member 25m toward the radially outer side. The radially outer end of the lubricating oil passage 58 is connected to a hole 43 provided in the inner raceway surface 42 a so as to penetrate the inner ring member 42 of the rolling bearing 41.

  The oil pump 51 attached to the center of the pump casing 22p and driven by the cylindrical portion 61c of the reinforcing member 61 is constituted by, for example, a cycloid pump, and sucks lubricating oil stored in the oil reservoir 53 from the lower end of the intake oil passage 52, Lubricating oil is discharged into the discharge oil passage 54.

  Next, the lubricating oil sequentially passes through the discharge oil passage 54 and the cooling oil passage 55 and is cooled in the cooling oil passage 55. Next, the lubricating oil sequentially passes through the communication oil passage 56 and the axial oil passage 57. A part of the lubricating oil flows out from one end of the speed reducer input shaft 25 and lubricates the bearing 64 and the inside of the speed reducer B. A part of the lubricating oil branches from the axial oil passage 57 to the lubricating oil passage 58 and flows radially outward to lubricate the rolling bearing 41 provided in the second eccentric member 25m. Further, since the lubricating oil flows radially outward by the action of centrifugal force, the surfaces of the curved plates 261, 26m, and 26n, the outer peripheral surface of the inner pin outer ring 31b, and the outer peripheral surface of the outer pin 27 are lubricated. Thereafter, the lubricating oil falls and is stored in an oil reservoir 53 provided at the lower portion of the speed reduction portion B. The lubricating oil circulation path is configured as described above.

  Although not shown, the above-described lubricating oil passage 58 may be provided in each of the eccentric members 25l, 25m, and 25n.

  FIG. 3 is an enlarged longitudinal sectional view showing the positional relationship between the eccentric members 25l, 25m, 25n and the curved plates 26l, 26m, 26n. The three eccentric members 25l, 25m, and 25n are sequentially arranged from the motor portion A toward the wheel hub bearing portion C in the axis O direction. Accordingly, the three curved plates 26l, 26m, and 26n that are rotatably supported by the three eccentric members 25l, 25m, and 25n are also sequentially moved from the motor portion A toward the wheel hub bearing portion C in the direction of the axis O. Arranged.

  FIG. 4 is an explanatory diagram schematically showing the positional relationship between the eccentric members 25l, 25m, and 25n viewed from the axis O direction IV of FIG. The center Xl of the first eccentric member 25l is disposed on one side in the direction perpendicular to the axis, the center Xm of the second eccentric member 25m is disposed on the other side in the direction perpendicular to the axis, and the center Xn of the third eccentric member 25n is in the direction perpendicular to the axis. Arranged on one side. That is, the center Xl and the center Xn have the same phase, and the center Xl and the center Xm have a phase different by 180 degrees. Thus, since the center Xl (Xn) and the center Xm are arranged with a phase different by 180 degrees, the rotation axis O is located on an imaginary straight line connecting the center Xl (Xn) and the center Xm.

  As a result, the first curved plate 26l arranged concentrically with the first eccentric member 25l is arranged in the same phase as the third curved plate 26n arranged concentrically with the third eccentric member 25n. Further, the second curved plate 26m arranged concentrically with the second eccentric member 25m is arranged with a phase 180 degrees different from the first curved plate 26l arranged concentrically with the first eccentric member 25l.

  The first curved plate 261 is arranged eccentric from the rotation axis O in the direction perpendicular to the axis. The second curved plate 26m is arranged eccentrically at a circumferential position that is 180 degrees out of phase with the first curved plate 26l on one side in the axis O direction of the first curved plate 26l. The third curved plate 26n is arranged eccentrically at a circumferential position where the second curved plate 26m has the same phase as the first curved plate 26l on one side in the axis O direction.

In this embodiment, the weight sum of the first curved plate 26l and the first eccentric member 25l is M _Sl , and the eccentric distance from the rotation axis O to the center of gravity of the first curved plate 26l and the first eccentric member 25l is E _Sl . The sum of weights of the second curved plate 26m and the second eccentric member 25m is M _Sm , and the eccentric distance from the rotation axis O to the center of gravity of the second curved plate 26m and the second eccentric member 25m is E _Sm . The weight sum of the third curved plate 26n and the third eccentric member 25n is M _Sn , and the eccentric distance from the rotation axis O to the center of gravity of the third curved plate 26n and the third eccentric member 25n is E _Sn . In FIG. 4, El is equal to E _Sl , Em is equal to E _Sm, and En is equal to E _Sn .

The above-described sum of weight and eccentric distance satisfy the following expression (1).
M _Sl E _S1 + M _Sn E _Sn = M _Sm E _Sm (1)
In this embodiment, the curved plates and the eccentric members are installed so that the centroids of the curved plate and the eccentric member coincide with each other, the centroids of the first curved plate 261 and the first eccentric member 251, the second curved plate 26 m and the second centroid. 2 An axial distance from the center of gravity of the eccentric member 25m is _defined as L _Slm . An axial distance between the center of gravity of the second curved plate 26m and the second eccentric member 25m and the center of gravity of the third curved plate 26n and the third eccentric member 25n is L _Smn . Lmn shown in FIG. 3 is equal to L _Smn, and _Llm is equal to L _Slm .

The above-described sum of weight, eccentric distance, and axial distance satisfy the following formula (2).
_{M Sl E Sl L Slm = M} Sn E Sn L Smn ······ (2)
According to the present invention, the first eccentric member 251 and the third eccentric member 25n are arranged eccentrically in the same phase, and the second eccentric member 25m arranged between the first eccentric member 251 and the third eccentric member 25n. However, they are eccentrically arranged at a phase different from these by 180 degrees, and the weight balance is optimized by the above formulas (1) and (2). Accordingly, static imbalance can be eliminated and dynamic imbalance can also be eliminated.

The weight and the sum _{M Sl,} not only the weight _{M Bl} weight _{M Al} and the first eccentric member 25l of the first curved plate 26l, bearing 41 attached thereto first curved plate 26l and the first eccentric member 25l It should be understood to include the weight of Similarly, the weight sum _{M Sm,} second curved plate 26m not only weight _{M Bm} weight _{M Am} and the second eccentric member 25m of the bearing 41 attached thereto a second curved plate 26m and the second eccentric member 25m It should be understood to include the weight of Similarly, the weight sum M _Sn is not only the weight M _An of the third curved plate 26n and the weight M _{Bn of} the third eccentric member 25n, but also the bearing 41 attached to the third curved plate 26n and the third eccentric member 25n. It should be understood to include the weight of

Further, in this embodiment, the following expressions (3) and (4) are satisfied.
M _Sl = M _Sn (3)
2M _S1 = M _Sm (4)
By substituting Equation (3) and Equation (4) into Equation (1) and Equation (2), the following Equation (5) and Equation (6) are derived.
E _Sl + E _Sn = 2E _Sm (5)
E _Sl L _Slm = E _Sn L _Smn (6)
Thereby, the combination of the 1st curve board 26l and the 1st eccentric member 25l and the combination of the 3rd curve board 26n and the 3rd eccentric member 25n can be made into the same component. Therefore, it is possible to provide an in-wheel motor drive device that is advantageous in terms of manufacturing cost.

Further, in this example, the following expression (7) is satisfied.
E _Sl = E _Sn (7)
By substituting equation (7) into equation (5), the following equation (8) is derived.
E _Sl = E _Sm = E _Sn (8)
By substituting equation (7) into equation (6), the following equation (9) is derived.
L _Slm = L _Smn (9)
Thereby, the eccentric distances of the three revolving members and the three eccentric members can be made equal, and the dimension of the speed reduction portion B in the direction perpendicular to the axis O can be made uniform.

In the present embodiment, the curved plates 26l, 26m, and 26n are similarly arranged. That is, the weight of the first curved plate 26l is M _Al , the eccentric distance from the rotational axis O to the center of gravity of the first curved plate 26l is E _Al , the weight of the second curved plate 26m is M _Am , and the second from the rotational axis O The eccentric distance to the center of gravity of the curved plate 26m is E _Am , the weight of the third curved plate 26n is M _An , and the eccentric distance from the rotation axis O to the center of gravity of the third curved plate 26n is E _An . El shown in FIG. 4 is equal to E _Al , Em is equal to E _Am, and En is equal to E _An .

And the following formula | equation (1 ') is satisfied.
M _Al E _Al + M _An E _An = M _Am E _Am (1 ')
Furthermore, the distance in the axis O direction between the center of gravity of the first curved plate 26l and the center of gravity of the second curved plate 26m is L _Alm, and the distance in the axis O direction between the center of gravity of the second curved plate 26m and the center of gravity of the third curved plate 26n is _Let L _Amn . Lmn shown in FIG. 3 is equal to L _Amn, and Llm is equal to L _Alm .
And the following formula (2 ′) is satisfied.
M _Al E _Al L _Alm = M _An E _An L L _Amn (2 ')
Further, in this embodiment, the following expressions (3 ′) and (4 ′) are satisfied.
M _Al = M _An (3 ')
2M _Al = M _Am (4 ')
By substituting Expression (3 ′) and Expression (4 ′) into Expression (1 ′) and Expression (2 ′), the following Expression (5 ′) and Expression (6 ′) are derived.
E _Al + E _An = 2E _Am (5 ')
E _Al L _Alm = E _An L _Amn (6 ')
Thereby, the 1st curve board 26l and the 3rd curve board 26n can be made into the same component. Therefore, it is possible to provide an in-wheel motor drive device that is advantageous in terms of manufacturing cost.

Further, in this embodiment, the following expression (7 ′) is satisfied.
E _Al = E _An (7 ')
By substituting equation (7 ′) into equation (5 ′), the following equation (8 ′) is derived.
E _Al = E _Am = E _An (8 ')
By substituting equation (7 ′) into equation (6 ′), the following equation (9 ′) is derived.
L _Alm = L _Amn (9 ')
As a result, the eccentric distances of the three curved plates 26l, 26m, and 26n can be made equal, and the dimension of the speed reduction portion B in the direction perpendicular to the axis O can be made uniform.

In the present embodiment, the eccentric members 25l, 25m, and 25n are similarly arranged. That is, weight of the first eccentric member 25l _{M Bl,} the eccentricity from the axis of rotation O to the centroids of the first eccentric member 25l and _{E Bl,} the weight of the second eccentric member 25 m _{M Bm,} from the axis of rotation O second The eccentric distance to the center of gravity of the eccentric member 25m is E _Bm , the weight of the third eccentric member 25n is M _Bn , and the eccentric distance from the rotation axis O to the center of gravity of the third eccentric member 25n is E _Bn . In FIG. 4, El is equal to E _Bl , Em is equal to E _Bm, and En is equal to E _Bn .

The following expression (1 ″) is satisfied.
_{M Bl E Bl + M Bn E} Bn = M Bm E Bm ······ (1'')
Further, the distance in the axis O direction between the center of gravity of the first eccentric member 25l and the center of gravity of the second eccentric member 25m is L _Blm, and the distance in the axis O direction between the center of gravity of the second eccentric member 25m and the center of gravity of the third eccentric member 25n is _Let L _Bmn . Lmn shown in FIG. 3 is equal to _{L Bmn,} LLM is equal to _{L Blm.}

And the following expression (2 ″) is satisfied.
_{M Bl E Bl L Blm = M} Bn E Bn L Bmn ······ (2'')
Further, in this embodiment, the following expressions (3 ″) and (4 ″) are satisfied.
M _Bl = M _Bn (3 ″)
_{2M Bl = M Bm ······ (4''} )
Substituting Expression (3 ″) and Expression (4 ″) into Expression (1 ″) and Expression (2 ″), the following Expression (5 ″) and Expression (6 ″) are derived. .
E _Bl + E _Bn = 2E _Bm (5 ")
_{E Bl L Blm = E Bn L} Bmn ······ (6'')
Thereby, the 1st eccentric member 25l and the 3rd eccentric member 25n can be made into the same component. Therefore, it is possible to provide an in-wheel motor drive device that is advantageous in terms of manufacturing cost.

Further, in this embodiment, the following expression (7 ″) is satisfied.
E _Bl = E _Bn (7 ")
When the formula (7 ″) is substituted into the formula (5 ″), the following formula (8 ″) is derived.
E _Bl = E _Bm = E _Bn ... (8 ″)
When the formula (7 ″) is substituted into the formula (6 ″), the following formula (9 ″) is derived.
_{L Blm = L Bmn ···· (9''} )
As a result, the eccentric distances of the three eccentric members 25l, 25m, and 25n can be made equal, and the dimension of the speed reduction portion B in the direction perpendicular to the axis O can be made uniform.

  In this case, the second eccentric member 25m arranged eccentrically at the circumferential position opposite to the first eccentric member 25l is, for example, a circumferential position that is 170 degrees different from the first eccentric member 25l, For example, if the circumferential position is 190 degrees different from that of the first eccentric member 25l, static imbalance and dynamic imbalance cannot be sufficiently eliminated. For this reason, in the present embodiment, the second eccentric member 25m located in the central portion in the axis O direction is arranged so that the phase is 180 degrees different from the first and third eccentric members 25l and 25n located on both sides in the axis O direction. is there.

  FIG. 5 is a plan view showing an arrangement layout of the in-wheel motor drive device 21. The vehicle body 11 includes four wheels on the front, rear, left and right. Of these, the left wheel 12L and the right wheel 12R are drive wheels. The left wheel 12L is coupled to the wheel hub 32 of the in-wheel motor drive device 21L disposed on the left side of the vehicle. The in-wheel motor drive device 21L is suspended under the floor of the vehicle body 11 by a suspension device (not shown). Similarly, the right wheel 12R is coupled to the wheel hub 32 of the in-wheel motor drive device 21R disposed on the right side of the vehicle. The in-wheel motor drive device 21R is also suspended below the floor of the vehicle body 11 by a suspension device (not shown). The in-wheel motor drive devices 21L and 21R are both the in-wheel motor drive device 21 described above, and are arranged symmetrically with respect to the center line of the vehicle body 11 extending in the vehicle front-rear direction.

  In the present embodiment, the three curved plates 26l, 26m, and 26n have the same inner and outer diameters, and the thickness in the axis O direction of the first curved plate 26l is equal to the thickness in the axis O direction of the third curved plate 26n. As a result, the first curved plate 26l, the second curved plate 26m, and the third curved plate 26n having the same outer diameter and inner diameter can be formed of a common metal material, which is advantageous in terms of manufacturing process and cost.

  In the present embodiment, the three eccentric members 25l, 25m, and 25n have the same inner and outer diameters, and the thickness of the first eccentric member 25l in the axis O direction is equal to the thickness of the third eccentric member 25n in the axis O direction. Thus, the first eccentric member 25l, the second eccentric member 25m, and the third eccentric member 25n having the same outer diameter and inner diameter can be formed of a common metal material, which is advantageous in terms of manufacturing process and cost.

  As shown in FIGS. 1 and 3, the first eccentric member 25l rotatably supports the first curved plate 26l by the ball bearing 41, and the second eccentric member 25m rotates the second curved plate 26m by the roller bearing 41. The third eccentric member 25n rotatably supports the third curved plate 26n by the ball bearing 41. This makes it possible to favorably support the second curved plate 26m having the largest bearing load among the three curved plates 26l, 26m, and 26n, thereby improving the durability of the speed reducing portion.

  Next, another embodiment of the present invention will be described. FIG. 6 is a developed cross-sectional view showing a vehicle motor drive device according to another embodiment of the present invention, and FIG. 7 is a plan view showing an arrangement layout of the vehicle motor drive device of the embodiment. Regarding such other embodiments, the same components as those shown in FIGS. 1 to 5 are denoted by the same reference numerals, description thereof is omitted, and different configurations will be described below.

  As shown in FIG. 6, a vehicle motor drive device 71 according to another embodiment includes a motor part A and a reduction part B that becomes a cycloid reducer, and a differential disposed adjacent to the reduction part B. A gear device 72 is further provided.

  The differential gear device 72 includes a ring gear 75, a differential gear case 76, a pinion mate shaft 77, a pair of pinion mate gears 78 and 79, and two side gears 82 and 83. This is a differential device that transmits driving force to the left and right wheels 12L, 12R (FIG. 7).

  The shaft portion 28b of the wheel side rotation member 28 extending along the axis O is rotatably supported on the casing 22 by the bearing 34 on the flange portion 28a side, and is rotatable on the casing 22 by the bearing 73 on the tip side far from the flange portion 28a. Supported by Both the bearing 34 and the bearing 73 are rolling bearings. The outer periphery of the shaft portion 28 b is coupled with the center of the gear 74 between the bearing 34 and the bearing 73, and the gear 74 rotates integrally with the wheel-side rotating member 28.

  The gear 74 meshes with the ring gear 75 of the differential gear device 72. The ring gear 75 is fixed to the outside of a differential gear case 76 that is rotatably supported by the casing 22 via bearings 80 and 81. In the differential gear case 76, a pinion mate shaft 77 is installed so as to be orthogonal to the rotation axis P, and a pair of pinion mate gears 78 and 79 are rotatably supported on the shaft 77 so that the inside of the differential gear case 76. Provided.

  Further, in the differential gear case 76, a pair of side gears 82 and 83 which are between the pinion mate gears 78 and 79 and mesh with the pinion mate gears 78 and 79 are rotatably arranged. The left side gear 82 is coupled to the left drive shaft 13L (FIG. 7) and rotates integrally. Further, the right side gear 83 is coupled to the right drive shaft 13R (FIG. 7) and integrally rotates.

  Similar to the lubricating oil path 58 described above, the lubricating oil paths 58 may be provided in the eccentric members 25l, 25m, and 25n, respectively. The lubricating oil flowing out from the lubricating oil passage 58 lubricates the bearings 41 and the surfaces of the curved plates 26l, 26m, and 26n.

  As shown in FIG. 7, the left wheel 12L is suspended under the floor of the vehicle body 11 by a suspension device (not shown). The inner side in the vehicle width direction of the left wheel 12L is coupled to the outer end in the vehicle width direction of the left drive shaft 13L extending in the vehicle width direction. The inner end in the vehicle width direction of the left drive shaft 13L is drivingly coupled to the vehicle motor drive device 71. The right wheel 12R is the same as the left wheel 12L and is arranged symmetrically with respect to the center line of the vehicle body 11 extending in the vehicle front-rear direction.

  According to this vehicle motor drive device 71, the speed reduction portion B of the vehicle motor drive device 71 supports the first curved plate 26 l so as to be rotatable and is eccentrically arranged from the rotation axis O in the direction perpendicular to the axis O. A second eccentric member 25l and a second curved plate 26m are rotatably supported and are eccentrically arranged at a circumferential position 180 degrees different from the first eccentric member 25l on one side in the axis O direction of the first eccentric member 25l. The eccentric member 25m and the third curved plate 26n are rotatably supported, and are eccentrically arranged at a circumferential position 180 degrees different from the second eccentric member 25m on one side in the axis O direction of the second eccentric member 25m. Since it includes the eccentric member 25n and satisfies the above-described expressions (1) and (2), the static unbalance of the vehicle motor drive device 71 can be eliminated, and the dynamic unbalance is also achieved. It can be erased. The left wheel 12L and the right wheel 12R may be either front wheels or rear wheels.

  Although the embodiment of the present invention has been described with reference to the drawings, the present invention is not limited to the illustrated embodiment. 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 and the vehicle motor drive device according to the present invention are advantageously used in electric vehicles and hybrid vehicles.

  11 body, 12L left wheel, 12R right wheel, 13L, 13R drive shaft, 21, 21L, 21R in-wheel motor drive device, 22 casing, 22a motor casing, 22p pump casing, 22t motor cover, 22b reduction gear casing, 23 stator, 24 rotor, 25 speed reducer input shaft, 25l first eccentric member, 25m second eccentric member, 25n third eccentric member, 26l first curved plate, 26m second curved plate, 26n third curved plate, 27 outer pin, 28 Wheel side rotating member, 31 inner pin, 32 wheel hub, 33 wheel hub bearing, 35 rotating shaft, 41 rolling bearing, 51 oil pump, 53 oil reservoir, 55 cooling oil passage, 57 axis oil passage, 58 lubricating oil passage, 61 Reinforcement member, 71 Motor drive device for vehicle, 72 Differential Rugiya apparatus.

Claims (13)

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 a wheel hub fixedly connected to the wheel side rotating member,
The speed reducer includes three disk-shaped eccentric members that are eccentric from the rotation axis of the motor-side rotating member and are coupled to the motor-side rotating member, and an inner circumference that is rotatable relative to the outer circumference of the three eccentric members. Attached to the three rotating members that perform a revolving motion around the rotation axis along with the rotation of the motor-side rotating member, and engages with the outer peripheral portion of the revolving member to cause the revolving motion of the revolving member. An outer peripheral engagement member, and an inner engagement member that combines with the wheel-side rotation member to extract the rotation of the revolving member,
The three revolving members are a first revolving member, a second revolving member arranged on one axial direction side of the first revolving member, and a second revolving member arranged further on the one axial side of the second revolving member. 3 revolving members,
The three eccentric members support the first revolving member so as to be relatively rotatable, and are arranged to be decentered in a direction perpendicular to the axis from the rotation axis, and to relatively rotate the second revolving member. A second eccentric member that is supported and eccentrically arranged at a circumferential position 180 degrees different from the first eccentric member on one axial direction side of the first eccentric member, and a third revolution member included in the revolution member are relatively rotated. A third eccentric member that freely supports and is arranged eccentrically at a circumferential position that is 180 degrees different from the second eccentric member on one axial direction side of the second eccentric member,
The mass sum of the first revolution member and the first eccentric member is M _Sl , and the eccentric distance from the rotation axis to the center of gravity of the first revolution member and the first eccentric member is E _Sl ,
The sum of weights of the second revolution member and the second eccentric member is M _Sm , and the eccentric distance from the rotation axis to the center of gravity of the second revolution member and the second eccentric member is E _Sm ,
The sum of weights of the third revolution member and the third eccentric member is M _Sn , and the eccentric distance from the rotation axis to the center of gravity of the third revolution member and the third eccentric member is E _Sn .
M _Sl E _S1 + M _Sn E _Sn = M _Sm E _Sm
An axial distance between the center of gravity of the first revolution member and the first eccentric member and the center of gravity of the second revolution member and the second eccentric member is L _Slm ,
L _Smn is an axial distance between the center of gravity of the second revolution member and the second eccentric member and the center of gravity of the third revolution member and the third eccentric member,
Satisfying _{M Sl E Sl L Slm = M} Sn E Sn L Smn, in-wheel motor drive device. The in-wheel motor drive device according to claim 1, wherein M _S1 = M _Sn and 2M _S1 = M _Sm are satisfied. The in-wheel motor drive device according to claim 2, wherein E _Sl = E _Sn is satisfied. The weight of the first revolving member is M _Al , the eccentric distance from the rotation axis to the center of gravity of the first revolving member is E _Al ,
The weight of the second revolving member is M _Am , the eccentric distance from the rotation axis to the center of gravity of the second revolving member is E _Am ,
The weight of the third revolving member is M _An , and the eccentric distance from the rotation axis to the center of gravity of the third revolving member is E _An ,
With satisfying _{M Al E Al + M An E} An = M Am E Am,
The axial distance between the center of gravity of the first revolving member and the center of gravity of the second revolving member is L _Alm ,
L _Amn is the axial distance between the center of gravity of the second revolving member and the center of gravity of the third revolving member,
Satisfying _{M Al E Al L Alm = M} An E An L Amn, in-wheel motor drive device according to any one of claims 1 to 3. The in-wheel motor drive device according to claim 4, wherein M _Al = M _An and 2M _Al = M _Am are satisfied.   6. The in-wheel motor drive device according to claim 5, wherein an axial thickness of the second revolution member is twice an axial thickness of the first revolution member. The in-wheel motor drive device according to claim 5 or 6, wherein E _Al = E _An is satisfied. The weight of the first eccentric member is M _Bl , and the eccentric distance from the rotation axis to the center of gravity of the first eccentric member is E _Bl .
The weight of the second eccentric member is M _Bm , the eccentric distance from the rotation axis to the center of gravity of the second eccentric member is E _Bm ,
The weight of the third eccentric member is M _Bn , and the eccentric distance from the rotation axis to the center of gravity of the third eccentric member is E _Bn .
M _B1 E _B1 + M _Bn E _Bn = M _Bm E _Bm
The axial distance between the center of gravity of the first eccentric member and the center of gravity of the second eccentric member is L _Blm .
The axial distance between the center of gravity of the second eccentric member and the center of gravity of the third eccentric member is L _Bmn .
Satisfying _{M Bl E Bl L Blm = M} Bn E Bn L Bmn, in-wheel motor drive device according to any one of claims 1 to 7. _{9. The in} -wheel motor drive device according to claim 8, wherein M _B1 = M _Bn and 2M _B1 = M _Bm are satisfied.   10. The in-wheel motor drive device according to claim 9, wherein the axial thickness of the second eccentric member is twice the axial thickness of the first eccentric member. The in-wheel motor drive device according to claim 9 or 10, wherein E _Bl = E _Bn is satisfied.   The first eccentric member rotatably supports the first revolving member with a ball bearing, the second eccentric member rotatably supports the second revolving member with a roller bearing, and the third eccentric member has the first eccentric member. The in-wheel motor drive device according to claim 1, wherein the three revolving members are rotatably supported by ball bearings. A motor unit that rotationally drives the motor-side rotating member; a deceleration unit that decelerates the rotation of the motor-side rotating member and transmits the rotation to the wheel-side rotating member; and a difference that drives and transmits the rotation of the wheel-side rotating member to a plurality of wheels. A moving device,
The speed reducer includes three disk-shaped eccentric members that are eccentric from the rotation axis of the motor-side rotating member and are coupled to the motor-side rotating member, and an inner circumference that is rotatable relative to the outer circumference of the three eccentric members. Attached to the three rotating members that perform a revolving motion around the rotation axis along with the rotation of the motor-side rotating member, and engages with the outer peripheral portion of the revolving member to cause the revolving motion of the revolving member. An outer peripheral engagement member, and an inner engagement member that combines with the wheel-side rotation member to extract the rotation of the revolving member,
The three revolving members are a first revolving member, a second revolving member arranged on one axial direction side of the first revolving member, and a second revolving member arranged further on the one axial side of the second revolving member. 3 revolving members,
The three eccentric members support the first revolving member so as to be relatively rotatable, and are arranged to be decentered in a direction perpendicular to the axis from the rotation axis, and to relatively rotate the second revolving member. While supporting the second eccentric member that is eccentrically arranged at a circumferential position 180 degrees different from the first eccentric member on one side in the axial direction of the first eccentric member, and the third revolving member, the third eccentric member is supported in a relatively rotatable manner. A third eccentric member disposed eccentrically at a circumferential position 180 degrees different from the second eccentric member on one axial direction side of the second eccentric member;
The mass sum of the first revolution member and the first eccentric member is M _Sl , and the eccentric distance from the rotation axis to the center of gravity of the first revolution member and the first eccentric member is E _Sl ,
The sum of weights of the second revolution member and the second eccentric member is M _Sm , and the eccentric distance from the rotation axis to the center of gravity of the second revolution member and the second eccentric member is E _Sm ,
The sum of weights of the third revolution member and the third eccentric member is M _Sn , and the eccentric distance from the rotation axis to the center of gravity of the third revolution member and the third eccentric member is E _Sn .
With satisfying the _{M Sl E Sl + M Sn E} Sn = M Sm E Sm,
An axial distance between the center of gravity of the first revolution member and the first eccentric member and the center of gravity of the second revolution member and the second eccentric member is L _Slm ,
L _Smn is an axial distance between the center of gravity of the second revolution member and the second eccentric member and the center of gravity of the third revolution member and the third eccentric member,
_{M Sl E Sl L Slm = M} Sn E Sn L satisfies _Smn, vehicle motor driving system.

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