JP2010260476A - In-wheel motor drive device and motor drive device for vehicles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in-wheel motor drive device which uniformizes transmission torque for a plurality of curved plates. <P>SOLUTION: The in-wheel motor drive is provided with: a speed reduction section which is equipped with several disc-shaped eccentric members that decenter from a rotational axis line of a motor side rotational member and connect with the motor side rotational member; several revolving members 26l, 26m, 26n that are supported by several eccentric members arranged in the axis line direction, respectively, and revolve around the rotational axis along with the rotation of the motor side rotational member; an outer periphery engaging member which is engaged with the outer periphery sections of the revolving members to generate the rotation movement of the revolving members; and an inner side engaging member 31 in a pin shape that is extended in parallel with the rotational axis line of which the root side is connected with a wheel side rotational member 28 and the tip side is connected with the revolving members to bring out the rotation movement of the revolving members. Inner pin collars 31b of the inner side engaging member are abutted on each of the several revolving members and are formed in such a way that an external diameter size Dl of the inner pin collars supported on the tip side is larger than an external diameter size Dn of the inner pin collar supported by the root side. <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 an inner engagement member that is a component part 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.

  The cycloid reduction mechanism includes an inner pin coupled to the wheel-side rotating member, and a curved plate that revolves at the same high rotational speed as the motor and rotates at a low rotational speed. And when an inner pin takes out rotation of a curved board, a rotation speed is decelerated and it transmits to a wheel side rotation member. Further, since the two curved plates are arranged so that the phases thereof are different by 180 degrees, the centrifugal force in the radial direction can be balanced. Further, since the plurality of inner pins engage with the curved plate, the transmission torque can be distributed and transmitted by the plurality of inner pins, and the transmission torque per inner pin can be reduced. it can.

JP 2006-258289 A

  However, the present inventor has found that there is a further improvement in the conventional in-wheel motor drive device. That is, the inner pin extending in parallel with the rotation axis is structured to be cantilevered by the wheel side rotation member, and therefore, the elastic deformation at the point of load application, that is, the deflection amount of the inner pin, varies depending on the position in the axial direction.

  FIG. 8 is an explanatory view showing, in an enlarged manner, a state in which the engagement portion between the inner pin and the curved plate during torque transmission is viewed from the axial direction. FIG. 9 is an explanatory view showing the side surface of the inner pin during torque transmission and exaggerating the elastic deformation of the inner pin for easy understanding. As shown in FIG. 8, the curved plate 102 that is rotatably supported on the outer periphery of the eccentric member 101 and revolves around the rotation axis rotates while engaging with the outer pin 103, and engages with the hole 104 of the curved plate 102. Torque is transmitted to the matching inner pin 105. The inner pin 105 receives a load F from the curved plate 102 during torque transmission by this rotation. The inner pin 105 that is cantilevered by the wheel-side rotating member 106 is elastically deformed (flexed) by the load F as shown in FIG.

  Therefore, as shown in FIG. 9, even with the same load F, the amount of elastic deformation is small on the base side close to the wheel side rotating member 106, and the amount of elastic deformation is large on the tip side far from the wheel side rotating member 106. Recognize.

  Two curved plates are arranged in the rotation axis direction. In addition to the conventional in-wheel motor drive device described above, a configuration in which a plurality of three or more curved plates are arranged in the axial direction in order to achieve smooth torque transmission may be employed. In the case of having a large number of curved plates, the inner pins extending in parallel with the rotation axis engage with the curved plates on the root side and the tip side having different elastic deformation amounts.

  For this reason, the conventional in-wheel motor drive device has a problem that a difference occurs in the transmission torque from the curved plate due to the difference in the amount of elastic deformation of the inner pin. That is, the transmission torque transmitted by the curve plate closer to the wheel side rotation member (base side) becomes larger than the transmission torque transmitted by the curve plate farther from the wheel side rotation member (tip side). The transmission torque is uneven among the curved plates.

  The torque transmitted by each curved plate is preferably equal. However, if the transmission torques of the curved plates are different, the durability and vibration performance of the speed reduction mechanism are degraded.

  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 make the transmission torque of a curved plate uniform among a plurality of curved plates.

  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 reduction gear is provided with a plurality of disk-shaped eccentric members that are eccentric from the rotation axis of the motor-side rotation member and coupled to the motor-side rotation member; and a plurality of disk-shaped eccentric members that are arranged in the axial direction. A plurality of revolving members that are supported by the eccentric members and perform revolving motions about the rotation axis along with the rotation of the motor side revolving member, and an outer periphery that engages with the outer peripheries of the revolving members to cause the revolving motion of the revolving members The engaging member has a pin shape extending in parallel with the rotation axis, the base side is coupled to the wheel side rotating member, and the tip end side is engaged with the revolving member to extract the rotation motion of the revolving member. And Side engaging member is formed such that the distal end side of the outer diameter is larger than the outer diameter of the root side.

  According to the present invention, the inner engagement member is formed such that the outer diameter dimension on the distal end side is larger than the outer diameter dimension on the root side, so that even if the inner engagement member is elastically deformed by deflection, The amount of displacement between the contact point on the base side of the inner engagement member that contacts the one revolution member and the contact point on the distal end side of the inner engagement member that contacts the other revolution member can be made substantially the same. . That is, the load that the base side of the inner engagement member receives from one revolution member is substantially the same as the load that the tip side of the inner engagement member receives from another revolution member. Therefore, the transmission torque transmitted by the revolution member closer to the wheel side rotation member (base side) can be made substantially the same as the transmission torque transmitted by the revolution member farther from the wheel side rotation member (tip side). Thus, the transmission torque can be made uniform among the plurality of revolution members.

  The pin-shaped inner engagement member may be in sliding contact with the revolving member, but is preferably configured to be in rolling contact with the revolving member. That is, the inner engagement member is a cylindrical inner pin whose root side is coupled to the wheel side rotation member and extends in the axial direction, and an annular body whose inner periphery is rotatably supported by the outer periphery of the inner pin, and the outer periphery is A plurality of inner pin collars that abut each of the plurality of revolving members, and the inner pin collars are arranged in the axial direction and the outer diameter of the inner pin collar supported on the tip side of the inner pin is the inner pin It is larger than the outer diameter of the inner pin collar supported on the root side. According to such an embodiment, the inner pin collar that is rotatably supported on the outer periphery of the inner pin becomes a component of the rolling bearing, and the inner engagement member is in rolling contact with the revolution member, so that friction loss can be reduced. it can. Moreover, the outer diameter of the inner pin collar supported on the tip side of the inner pin is larger than the outer diameter of the inner pin collar supported on the root side of the inner pin. The transmission torque transmitted by the revolution member on the base side can be made substantially the same as the transmission torque transmitted by the revolution member farther from the wheel side rotation member (inner pin tip side). The transmission torque can be made uniform.

  Although the present invention is not limited to one embodiment, the outer periphery of the inner pin collar may be formed in a curved shape so that the outer diameter dimension decreases from the axial center to the both ends in the axial direction. According to this embodiment, since the outer diameter dimension of both axial ends of the inner pin collar is smaller than the outer diameter dimension of the axial central portion, it is possible to prevent edge load from acting on the outer peripheral surface of the inner pin collar. This contributes to a longer life of the inner engagement member.

  Although the present invention is not limited to an embodiment, as a specific example, the outer periphery of the inner pin collar is formed in an arc shape bulging outward in a cross-sectional shape in a plane including the axis.

  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 is arranged in the axial direction and a plurality of disc-shaped eccentric members that are eccentric from the rotation axis of the motor side rotating member and coupled to the motor side rotating member. A plurality of revolving members that are supported by a plurality of eccentric members and that revolve around the rotation axis along with the rotation of the motor-side rotating member, and engage with the outer periphery of the revolving member to rotate the revolving member. An outer peripheral engagement member to be generated and a pin shape extending in parallel with the rotation axis, the inner side engagement member taking out the rotation motion of the revolution member by coupling the root side to the wheel side rotation member and engaging the tip side with the revolution member And Side engaging member is formed such that the distal end side of the outer diameter is larger than the outer diameter of the root side.

  According to the present invention, the inner engagement member is formed such that the outer diameter dimension on the distal end side is larger than the outer diameter dimension on the root side, so that even if the inner engagement member is elastically deformed by deflection, The amount of displacement between the contact point on the base side of the inner engagement member that contacts the one revolution member and the contact point on the distal end side of the inner engagement member that contacts the other revolution member can be made substantially the same. . That is, the load that the base side of the inner engagement member receives from one revolution member is substantially the same as the load that the tip side of the inner engagement member receives from another revolution member. Therefore, the transmission torque transmitted by the revolution member closer to the wheel side rotation member (base side) can be made substantially the same as the transmission torque transmitted by the revolution member farther from the wheel side rotation member (tip side). Thus, the transmission torque can be made uniform among the plurality of revolution members.

  As described above, according to the present invention, since the inner engagement member is formed so that the outer diameter dimension on the distal end side is larger than the outer diameter dimension on the root side, one revolution member positioned on the inner engagement member root side. The load received by the base side of the inner engagement member from the inner side is substantially the same as the load received by the front end side of the inner engagement member from the other revolving member located on the front side of the inner engagement member. Therefore, the transmission torque can be made uniform among the plurality of revolution members, and the durability of all the revolution members is made substantially equal, which contributes to the extension of the life of the speed reduction portion.

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 explanatory drawing which expands and shows the area | region shown by III in FIG. It is explanatory drawing which shows a mode that one inner pin collar of the Example was taken out and cut | disconnected by the plane containing an axis line. It is a longitudinal cross-sectional view which shows the state which arranged three inner pin collars of the Example in the axial direction of the inner pin. It is a longitudinal cross-sectional view which shows the mode during torque transmission of the inner pin and inner pin collar shown in FIG. It is an expanded sectional view showing the motor drive device for vehicles which becomes other examples of the present invention. It is explanatory drawing which expands and shows a mode that the engaging part of the inner pin and curve board during torque transmission was seen from the axial direction. It is explanatory drawing which expressed the side surface of the inner pin in torque transmission, and exaggerated the elastic deformation of the inner pin for easy understanding.

  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 device according to this embodiment. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is an explanatory diagram showing the region indicated by III in FIG. 1 in an enlarged manner.

  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 stator 23 via a gap opened radially on the inner diameter side of the stator 23, and the rotor 24. Is a radial gap motor provided with a rotary shaft 35 that is fixedly connected to the center of the rotor 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. The center collar 29 is attached to the space between the curved plates 26m and 26n, and is engaged with the inner pin 31 and the center collar 30 that is in contact with the end surfaces of the curved plates 26m and 26n to prevent the curved plate from tilting. And a rotating member 61 for driving the oil pump 51.

  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.

  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.

  So far, the second curved plate 26m has been described as a representative, but the first curved plate 26l is also concentrically attached to the outer periphery of the first eccentric member 25l. Similarly, the third curved plate 26n is concentrically attached to the outer periphery of the third eccentric member 25n. The first curved plate 26l and the third curved plate 26n are also supported rotatably by the rolling bearing 41, and specifically supported by a deep groove ball bearing. In this specification, when describing as the curved plate 26, it indicates at least one of the first curved plate 26l to the third curved plate 26n.

  Returning to FIG. 1, the plurality of inner pins 31 extend in parallel with the axis O and are cantilevered in common on the wheel-side rotating member 28 on the base side far from the motor part A. The wheel-side rotation member 28 includes a shaft portion 28b extending along the axis O, and a flange portion 28a that is formed at an end portion of the shaft portion 28b and is coupled to the root 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.

  An annular rotating member 61 is engaged with the tip of the inner pin 31 on the side away from the flange portion 28a. The rotating member 61 includes a flange-shaped annular portion 61b that engages with the tips of the plurality of inner pins 31, and a cylindrical portion 61c that extends from the inner diameter portion of the annular portion 61b to the motor portion A in the direction of the axis O. A coupling portion between the speed reduction portion input shaft 25 and the rotation shaft 35 is inserted into the central hole of the rotation member 61. The tip of the cylindrical portion 61c is drivingly coupled to the oil pump 51. When the plurality of inner pins 31 rotate together with the wheel-side rotating member 28, the rotating member 61 is driven by the inner pin 31 to drive the oil pump 51. The oil pump 51 circulates lubricating oil inside the in-wheel motor drive device 21.

  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 around 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. The plates 26l, 26m, and 26n are caused to rotate.

  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 circumference of the inner pin collar 31b of the needle roller bearing 31a inserted into the through hole 30a is sufficiently narrower than the inner diameter of the through hole 30a, and the hole wall surface of the through hole 30a is accompanied by the rotation of the curved plates 26l, 26m, and 26n. Abut. 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 outer pin 27 is rotatable with respect to the outer pin holding portion 45, and the needle roller bearing 31a is provided at a position where the outer pin 27 comes into contact with the curved plates 26l, 26m, 26n of the inner pin 31, thereby reducing the frictional resistance. Therefore, the transmission efficiency of the deceleration unit B is improved.

  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.

  Referring to FIG. 3, which is an explanatory view showing the area indicated by III in FIG. 1 in an enlarged manner and is a longitudinal sectional view showing the inner pin in an enlarged manner, a pin-shaped inner pin extending parallel to the rotation axis O Reference numeral 31 denotes an inner engagement member whose base side is coupled to the wheel-side rotation member 28 and whose front end is engaged with the curved plates 26l, 26m, and 26n to extract the rotational motion of these curved plates 26l, 26m, and 26n.

  Three needle roller bearings 31a described above are arranged on the outer periphery of the inner pin 31 in the axial direction. The three needle roller bearings 31a are provided at axial positions corresponding to the curved plates 26l, 26m, and 26n, respectively. Therefore, three inner pin collars 31b that serve as outer rings of the needle roller bearing 31a are arranged in the axial direction, the inner periphery is an annular body that is rotatably supported on the outer periphery of the inner pin 31, and the outer periphery is a curved plate 26l. , 26m, and 26n, respectively. That is, the outer peripheral surface (outer diameter dimension Dn) of the inner pin collar 31b on the base side of the inner pin 31 is in contact with the inner peripheral surface of the through hole 30a of the curved plate 26n. The outer peripheral surface (outer diameter dimension Dl) of the inner pin collar 31b on the tip side of the inner pin 31 is in contact with the inner peripheral surface of the through hole 30a of the curved plate 26l. The outer peripheral surface (outer diameter dimension Dm) of the remaining inner pin collar 31b located between these inner pin collars is in contact with the inner peripheral surface of the through hole 30a of the curved plate 26m. Note that these subscripts l, m, and n correspond to the curved plates 26l, 26m, and 26n that abut.

  The three inner pin collars 31b arranged in the direction of the axis O are arranged on the distal end side of the inner pin 31 with the outer diameter dimensions of these three inner pin collars 31b indicated by arrows facing each other as Dl, Dm, and Dn. The outer diameter dimension Dl of the supported inner pin collar is larger than the outer diameter dimension Dm of the inner pin collar supported on the root side of the inner pin 31. Further, the outer diameter dimension Dm of the inner pin collar supported on the tip side of the inner pin 31 is larger than the outer diameter dimension Dn of the inner pin collar supported on the root side of the inner pin 31.

  That is, the outer diameter dimensions D1, Dm, and Dn of these three inner pin collars 31b satisfy Dl> Dm> Dn, and the outer diameter dimension of the inner pin collar 31b increases from the root side to the tip side of the inner pin 31. It grows. In addition to the three combinations of the curved plate 26 and the inner pin collar 31b according to the present embodiment, the same applies even if the number of such combinations is two or four or more.

  The outer periphery of the inner pin collar 31b is formed in a curved shape so that the outer diameter dimension decreases from the axial center to the both ends in the axial direction. For example, in the inner pin collar 31b of the cylindrical body, tapered chamfers having an angle of 45 degrees are provided at both ends in the axial direction.

  Alternatively, the outer periphery of the inner pin collar 31b is formed in a curved shape so that the outer diameter dimension decreases from the axial center to the both ends in the axial direction. FIG. 4 is an explanatory view showing a state in which one inner pin collar 31b is taken out and cut along a plane including the axis. As a specific example, as shown in FIG. 4, the outer periphery of the inner pin collar 31 b is formed in an arc shape having a radius R bulging outward in a cross-sectional shape in a plane including the axis. Here, since R is much larger than the outer diameter D of the inner pin collar 31b, the outer peripheral surface of the inner pin collar 31b is a gentle spherical band that is almost close to the cylindrical side surface. The outer diameter D means the outer diameter dimensions Dl, Dm, Dn of the three inner pin collars 31b.

  FIG. 5 is a longitudinal sectional view showing a state in which three inner pin collars 31b described above are arranged in the axial direction of the inner pin 31, and corresponds to FIG. The outer diameters D1, Dm, and Dn of the three inner pin collars 31b are indicated by arrows facing each other. In FIG. 5, Dn <Dm <Dl is exaggerated so that the outer diameters Dl, Dm, and Dn can be easily understood. According to the present embodiment, the outer diameter of the inner pin collar 31b positioned on the distal end side of the inner pin 31 is formed so that the outer diameter of the inner pin collar 31b positioned on the root side of the inner pin 31 is also increased. It is understood.

  Next, the operation of the three inner pin collars 31b according to this embodiment will be described.

  FIG. 6 is a longitudinal sectional view showing a state during torque transmission of the inner pin 31 and the inner pin collar 31b shown in FIG. 5, and is an explanatory diagram exaggerating the elastic deformation of the inner pin 31 for easy understanding. It is. The inner pin collar 31b which becomes the outer periphery of the inner engagement member is formed so that the outer diameter dimension on the tip side of the inner pin is larger than the outer diameter dimension on the root side of the inner pin. Even if elastically deformed as shown in FIG. 6, the abutment point of the root-side inner pin collar 31b that abuts on one curved plate 26n (not shown in FIG. 6) and another curved plate 26l (see FIG. It is possible to make the amount of displacement with the contact point of the tip side inner pin collar 31b in contact with (not shown in FIG. 6) substantially the same. Further, in this embodiment in which three or more inner pin collars 31b are provided corresponding to three or more curved plates 26, as shown by a one-dot chain line, a curved plate 26m at the center in the axial direction (not shown in FIG. 6). It is possible to make the amount of displacement of the contact point of the inner pin collar 31b in the central portion that contacts with the contact point of the other inner pin collar 31b substantially the same.

  As a result, the load Fn received by the root side inner pin collar 31b from one curved plate 26n (not shown in FIG. 6) and the tip side inner pin collar 31b from the other curved plate 26l (not shown in FIG. 6). The load Fl received is substantially the same, and the load Fm received by the inner pin collar 31b from the curved plate 26m (not shown in FIG. 6) in the axial center is substantially the same.

  Therefore, the transmission torque transmitted by the curve plate 26n closer to the wheel side rotation member 28 (base side) is made substantially the same as the transmission torque transmitted by the curve plate 26l farther from the wheel side rotation member (tip side). Accordingly, the transmission torque transmitted by the curved plate 26m arranged at the center can be made substantially the same as the transmission torque transmitted by the other curved plates 26l and 26n. As a result, the transmission torque can be made uniform among the plurality of curved plates 26l, 26m, and 26n.

  Therefore, according to the present embodiment, the durability of all the curved plates 26l, 26m, and 26n and the inner pin collars 31b corresponding to the curved plates 26l, 26m, and 26n are substantially equal, which contributes to the extension of the life of the speed reducing portion B.

  Further, according to the present embodiment, the inner pin 31 and the three needle roller bearings 31a arranged in the axial direction of the inner pin 31 constitute the inner engagement member, so that the three needle roller bearings 31a. Can be brought into rolling contact with the three curved plates 26l, 26m and 26n to reduce the friction loss.

  In addition, three inner pin collars 31b that are rotatably supported on the outer periphery of the inner pin 31 as components of the needle roller bearing 31a are arranged in the axial direction and are supported on the tip side of the inner pin 31. Since the outer diameter dimension of the collar 31b is larger than the outer diameter dimension of the inner pin collar 31b supported on the root side of the inner pin 31, the curved plate 26n closer to the wheel side rotating member 28 (the inner pin 31 root side). Can be made substantially the same as the transmission torque transmitted by the curved plate 28l farther from the wheel-side rotating member 28 (on the tip side of the inner pin 31), and a plurality of curved plates 26l, 26m, 26n can be obtained. The transmission torque can be made uniform between the two.

  Although not shown, in the case of the embodiment in which the needle roller bearing 31a is not provided and the inner pin 31 is in sliding contact with the plurality of curved plates 26l, 26m, 26n, the outer diameter of the inner pin 31 on the tip side is the inner diameter. The pin 31 is formed to be larger than the outer diameter dimension on the base side.

  Further, in this embodiment, as shown in FIGS. 4 to 6, the outer periphery of the inner pin collar 31b is formed in a curved shape so that the outer diameter dimension becomes smaller from the central portion in the axial direction toward both ends in the axial direction. The edge load can be prevented from acting on the outer peripheral surface of the inner pin collar 31b, which contributes to a longer life of the inner pin collar 31b.

  Further, in this embodiment, as shown in FIG. 4, the outer periphery of the inner pin collar 31b is formed in an arc shape having a radius R that bulges outward in a cross-sectional shape in a plane including the axis. As a result, the outer periphery of the inner pin collar 31b can abut on the inner periphery of the through hole 30a while following the elastic deformation behavior of the inner pin 31, and the amount of deflection of the inner pin 31 changes due to the change in the load F. However, the load from the curved plate 26 can be suitably handled. Therefore, it is advantageous for the durability and extension of the life of the deceleration part B.

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

  As shown in FIG. 7, a vehicle motor drive device 71 according to another embodiment includes a motor part A and a speed reduction part B that serves as a cycloid reducer, and a differential disposed adjacent to the speed 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 left and right wheels (not shown) of the vehicle.

  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 a left drive shaft (not shown) extending along the rotation axis P and integrally rotates. Further, the right side gear 83 is coupled to a right drive shaft (not shown) extending along the rotation axis P and integrally rotates.

  The vehicle motor drive device 71 includes a differential gear device 72 that transmits and transmits the rotation of the wheel-side rotation member 28 to a plurality of wheels, and the speed reduction portion B has a pin shape extending in parallel with the rotation axis O. The base side is coupled to the wheel-side rotating member 28, and the tip side is engaged with the curved plates 26l, 26m, 26n to have an inner pin 31 as an inner engaging member for taking out the rotational motion of the curved plates 26l, 26m, 26n.

  Then, in the three inner pin collars 31b rotatably supported on the outer periphery of the inner pin 31 as inner engagement members (the outer diameter dimension of the tip side inner pin collar 31b is the root side inner pin collar as shown in FIG. 5). Since the inner engagement member is formed so as to be larger than the outer diameter of 31b, even if the inner engagement member is elastically deformed due to the deflection, the inner engagement that makes contact with one revolving member as shown by a one-dot chain line shown in FIG. The displacement amount between the contact point on the base side of the member and the contact point on the distal end side of the inner engagement member that contacts the other revolving member can be made substantially the same.

  Therefore, the transmission torque transmitted by the curve plate 26n closer to the wheel side rotation member 28 (base side) is substantially the same as the transmission torque transmitted by the curve plate 26l farther from the wheel side rotation member 28 (tip side). Thus, the transmission torque can be made uniform among the plurality of curved plates 26l, 26m, and 26n.

  According to this embodiment shown in FIG. 7, the durability of all the curved plates 26l, 26m, and 26n and the inner pin collars 31b corresponding to the curved plates 26l, 26m, and 26n are made substantially equal. Contributes to life extension.

  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.

  21 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 reduction gear input shaft, 25l first eccentric member, 25m second eccentric member , 25n third eccentric member, 26 curve plate (revolution member), 26l first curve plate (revolution member), 26m second curve plate (revolution member), 26n third curve plate (revolution member), 27 outer pin, 28 Wheel side rotating member, 31 inner pin (inner engaging member), 31a needle roller bearing (inner engaging member), 31b inner pin collar (inner engaging member), 32 wheel hub, 33 wheel hub bearing, 35 rotating shaft , 41 Rolling bearing, 51 Oil pump, 61 Rotating member, 71 Motor drive device for vehicle, 72 Differential Lugia device.

Claims (5)

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 is supported by a plurality of disk-shaped eccentric members that are eccentric from the rotation axis of the motor-side rotation member and coupled to the motor-side rotation member, and the plurality of eccentric members arranged in the axial direction, respectively. A plurality of revolving members that revolve around the rotation axis as the rotating member rotates, an outer peripheral engaging member that engages with an outer peripheral portion of the revolving member to generate a revolving motion of the revolving member, A pin shape extending parallel to the rotation axis, the root side is coupled to the wheel side rotation member, and the tip end side is engaged with the revolution member to take out the rotation motion of the revolution member;
The inner engagement member is an in-wheel motor drive device that is formed such that the outer diameter dimension on the distal end side is larger than the outer diameter dimension on the root side. The inner engagement member is a cylindrical inner pin whose base side is coupled to the wheel side rotation member and extends in the axial direction, and an annular body whose inner periphery is rotatably supported on the outer periphery of the inner pin. Includes a plurality of inner pin collars that respectively contact the plurality of revolving members,
The plurality of inner pin collars are arranged in the axial direction, and an outer diameter dimension of the inner pin collar supported on the tip side of the inner pin is larger than an outer diameter dimension of the inner pin collar supported on the root side of the inner pin. The in-wheel motor drive device according to claim 1, which is larger.   3. The in-wheel motor drive device according to claim 2, wherein an outer periphery of the inner pin collar is formed in a curved shape so that an outer diameter dimension decreases from an axial center portion toward both axial ends.   4. The in-wheel motor drive device according to claim 3, wherein an outer periphery of the inner pin collar is formed in an arc shape that bulges outward in a cross-sectional shape in a plane including an axis. 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 is supported by a plurality of disk-shaped eccentric members that are eccentric from the rotation axis of the motor-side rotation member and coupled to the motor-side rotation member, and the plurality of eccentric members arranged in the axial direction, respectively. A plurality of revolving members that revolve around the rotation axis as the rotating member rotates, an outer peripheral engaging member that engages with an outer peripheral portion of the revolving member to generate a revolving motion of the revolving member, A pin shape extending parallel to the rotation axis, the root side is coupled to the wheel side rotation member, and the tip end side is engaged with the revolution member to take out the rotation motion of the revolution member;
The inner engagement member is a vehicle motor drive device that is formed such that the outer diameter dimension on the distal end side is larger than the outer diameter dimension on the root side.

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