JP2010138988A - In-wheel motor drive unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in-wheel motor drive unit capable of assembling an outer circumferential engagement member precisely in parallel to an axis, and easy to be assembled. <P>SOLUTION: A deceleration part B has an outer pin holding part 45. The outer pin holding part 45 includes a cylindrical part 46 arranged coaxially with the axis O, and ring parts 47, 48 projected respectively from both ends of the cylindrical part 46 toward an inside diametric direction, and stores eccentric members 25a, 25b, curved plates 26a, 26b, an outer pin 27, and an inner pin 31, in its inside. The outer pin 27 is constituted to support axial-directional both end parts by the ring parts 47, 48, and is extended in parallel to the axis O. An inside diameter of one ring part 48 is larger than outside diameters of the curved plates 26a, 26b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a mounting structure for an outer peripheral engagement member provided inside an in-wheel motor drive device.

A conventional in-wheel motor drive device is described in, for example, Japanese Patent Application Laid-Open No. 2008-44537 (Patent Document 1). An in-wheel motor drive device described in Patent Document 1 includes a drive motor, a speed reducer that receives a driving force from the drive motor, decelerates the rotation speed, and outputs it to the wheel side, and an output shaft of the speed reducer The hub members of the wheels to be coupled are arranged coaxially. This speed reducer is a cycloid speed reduction mechanism, and a high speed reduction ratio can be obtained as compared with a planetary gear speed reduction mechanism that is general as a conventional speed reducer. Therefore, the required torque of the drive motor can be reduced, which is advantageous in that the size and weight of the in-wheel motor drive device can be reduced. In the cycloid reduction mechanism, the outer pin is rotatably supported on the casing by a needle roller bearing. Therefore, the contact resistance between the curved plate and the outer pin can be greatly reduced, and the torque loss of the speed reducer can be prevented.
JP 2008-44537 A

  By the way, in patent document 1, since an outer pin contact | abuts to a curved board, an outer pin must be hold | maintained in parallel with an axis line, and when parallel accuracy is low, there is a concern about uneven wear of an outer pin. On the other hand, one end of the outer pin is supported by the casing on the hub member side, the other end of the outer pin is supported by the casing on the drive motor side, and the casings on both sides are coupled in the axial direction with bolts or the like. In order to assemble the outer pin in parallel with the axis with high accuracy, the circumferential positioning of the outer pin and the casing and the positioning of the casings on both sides must be strictly performed, which is difficult in assembling.

  An object of the present invention is to provide an in-wheel motor drive device capable of assembling an outer pin with high accuracy in parallel with an axis.

  For this purpose, an in-wheel motor drive 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 the wheel side It is assumed that a wheel hub fixedly connected to the rotating member is provided. The speed reduction unit is a disc-shaped eccentric member that is eccentric from the axis of the motor-side rotating member and is coupled to one end of the motor-side rotating member, and an inner periphery is attached to the outer periphery of the eccentric member so that the outer periphery can be rotated relative to the outer periphery. A curved plate having a plurality of curved recesses formed in the radial direction and spaced at equal intervals in the circumferential direction, and a plurality of curved recesses disposed at equal intervals in the circumferential direction centered on the axis, and engaged with the curved recesses as the eccentric member rotates. An outer engagement member that revolves and rotates the curved plate, an inner engagement member that is coupled to the wheel-side rotation member and engages with a hole provided between the outer peripheral portion and the axis of the curved plate, and coaxial with the axis Cylindrical outer engagement having an eccentric member, a curved plate, an outer engagement member, and an inner engagement member provided therein with a cylindrical portion to be arranged and ring portions protruding in the inner diameter direction from both ends of the cylindrical portion. And a member holding part. The outer engagement member is supported by the ring portions at both ends in the axial direction and extends in parallel with the axis, and the inner diameter of at least one of the ring portions is larger than the outer diameter of the curved plate.

  According to this invention, the speed reduction part has the cylindrical outer engagement member holding part that accommodates the eccentric member, the curved plate, the outer engagement member, and the inner engagement member. And since the axial direction both ends of an outer engagement member are each supported by the axial direction both ends of an outer engagement member holding | maintenance part, it is possible to hold | maintain several outer engagement members in parallel with an axis with high precision. become.

  In the present invention, the pair of ring members provided at both ends of the outer engagement member holding portion respectively support both ends in the axial direction of the outer engagement member. It is necessary to put inside the holding part.

  According to the present invention, since the inner diameter of at least one of the ring portions is larger than the outer diameter of the curved plate, the curved plate can be inserted into the inside from the end portion of the outer engagement member holding portion. Therefore, the assembly work of the in-wheel motor drive device is facilitated.

  In addition, since the outer periphery of a curved plate forms a waveform curve, the outer diameter of a curved plate here should be understood as the diameter of the circumscribed circle in the outer periphery of a curved plate. Further, since the inner circumference of the ring portion does not need to be a 360 ° circumference, the inner diameter of the ring portion here is to be understood as the diameter of the inscribed circle in the inner circumference of the ring portion.

  The present invention is not limited to one embodiment, and the inner diameter of both of the pair of ring portions may be larger than the outer diameter of the curved plate. The end portion of the outer engagement member may have any shape that can be connected to the ring portion, such as a tapered shape that penetrates and is fixed to the inner end surface of the ring. Alternatively, as one embodiment, the end of the outer engagement member has a circular cross-sectional shape, and at least one of the ring portions has an arcuate cutout that fits with the end of the outer engagement member on the inner periphery And the arc portion of the notch is closely fitted to the outer periphery of the outer end of the outer engagement member that exceeds 180 degrees in the circumferential direction.

  According to such an embodiment, the arc portion of the notch is closely fitted to the outer circumference of the outer end of the outer engagement member that exceeds 180 degrees in the circumferential direction, and therefore on a plane perpendicular to the axis O. The outer engagement member can be gripped so as not to be displaced. In addition, the outer engagement member can be inserted into the ring portion in the axial direction, and the assembly efficiency is improved.

  The present invention is not limited to one embodiment, and the outer engagement member may be fixed to the ring portion in a non-rotatable manner. Alternatively, as one embodiment, a plurality of outer engagement members are arranged in an outer pin extending in the axial direction, an outer ring that surrounds the outer peripheral surface of the outer pin at both ends of the outer pin, and an annular gap between the outer ring and the outer pin. Rolling elements.

  According to such an embodiment, since the outer ring that surrounds the outer peripheral surface of the outer pin at both ends of the outer pin and the rolling elements that are arranged in a plurality of annular gaps between the outer ring and the outer pin, the outer pin is mounted by the rolling bearing. It can be supported rotatably. Therefore, the friction when the curved plate comes into contact with the outer pin can be remarkably reduced, and the power transmission efficiency of the speed reducing portion can be improved.

  Preferably, the outer engagement member holding portion includes an outer ring locking member that is attached to the inner end surface of the ring portion and restricts movement toward the inner side in the axial direction of the outer ring. According to this embodiment, even if it is the structure which supports an outer pin rotatably with a rolling bearing, it can prevent that the outer ring | wheel of a rolling bearing slips out from a ring part.

  Preferably, the outer ring locking member has an arc shape extending in the circumferential direction of the ring portion. According to this embodiment, since the outer ring locking member extends in the circumferential direction of the ring portion, a plurality of outer rings arranged at equal intervals in the circumferential direction can be fixed in the axial direction by one outer ring locking member. This makes it possible to improve assembly efficiency.

  The outer ring locking member has a C shape with a part in the circumferential direction cut away. According to such an embodiment, it is possible to prevent all the outer rings from slipping out with one outer ring locking member extending substantially 360 degrees in the circumferential direction. Moreover, since both ends of the C-shaped outer ring locking member are opposed to each other via a gap, the outer ring locking member is elastically deformed so as to close the gap during assembly work, and the outer ring locking member It becomes possible to easily enter the outer engagement member holding portion from the periphery. Therefore, the assembly efficiency is improved.

  The present invention is not limited to one embodiment, and the outer ring locking member may take various forms. Alternatively, as one embodiment, the outer ring locking member has a circular arc notch through which the outer pin passes and a locking portion positioned along the annular end surface of the outer ring is set in the same circumferential direction as the outer engagement member. Prepare at intervals. According to this embodiment, the axial movement of the entire bearing including the outer ring can be suitably prevented.

  Preferably, the outer ring locking member is a flat belt-like body, and is attached to the ring portion so that the flat surface is perpendicular to the axis. According to this embodiment, the outer ring locking member can be made thin and lightweight. Therefore, the outer ring locking member can be attached to the inner space of the outer engaging member holding portion which is severely limited in space and narrow.

  The present invention is not limited to one embodiment, and the locking portion extends along the annular end surface of the outer ring, and the arc shape of the annular end surface is 90 degrees (quarter circle) to 270 degrees, in various forms. There may be. As one embodiment, the locking portion has a semicircular shape when viewed from the axial direction.

  The present invention is not limited to one embodiment, and the locking portion may be located radially outside the outer pin with the axis as the center. Alternatively, the locking portion may be arranged between the axis and the outer pin.

  In the latter case, preferably, the outer ring locking member is bent at one end in the circumferential direction and engaged with the outer engagement member holding portion. According to this embodiment, the outer ring locking member can be prevented from rotating during assembly. Therefore, the assembly efficiency is improved.

  Thus, in the in-wheel motor drive device of the present invention, both ends in the axial direction of the outer engagement member are respectively supported by the pair of ring portions provided at both ends in the axial direction of the outer engagement member holding portion. The plurality of outer engagement members can be accurately arranged at equal intervals in the circumferential direction, and can be held parallel to the axis with high accuracy.

  Further, since the inner diameter of at least one of the ring portions is larger than the outer diameter of the curved plate, the curved plate can be inserted into the inside from the end portion of the outer engagement member holding portion. Therefore, the assembly work of the in-wheel motor drive device can be facilitated and the assembly efficiency can be improved.

  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 of the present embodiment. 2 is a cross-sectional view taken along the line II-II in FIG.

  An in-wheel motor drive device 21, part or all of which is disposed in the inner space area of a drive wheel road wheel, a motor unit A that generates a driving force, and a speed reduction unit that decelerates and outputs the rotation of the motor unit A B and a wheel hub bearing portion C that transmits the output from the speed reduction portion B to a drive wheel (not shown). 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 is fixedly connected to the stator 23 fixed to the motor casing 22a, the rotor 24 arranged at a position facing the stator 23 through a gap opened radially in the stator 23, and the rotor 24 inside. It is a radial gap motor including a motor output shaft 35 that rotates integrally with the rotor 24. Alternatively, an axial gap motor may be used.

  The pump casing 22 p which is a part of the casing 22 forms a boundary with the speed reduction part B at one end of the motor part A, and rotatably supports one end part of the motor output shaft 35 via the bearing 62. Further, the pump casing 22 p includes an oil pump 51. The motor cover 22 t that is a part of the casing 22 forms the end surface of the motor part A at the other end of the motor part A, and rotatably supports the other end part of the motor output shaft 35 via the bearing 63. The motor cover 22t is an end portion of the motor part A and also an end portion of the in-wheel motor drive device 21.

  One end of the motor output shaft 35 is coupled to a speed reducing portion input shaft 25 that is rotatably provided inside the speed reducing portion B. 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 portion A is coupled to one end of the motor output shaft 35. In the middle between these two ends, eccentric members 25a and 25b are formed on the outer periphery of the speed reducing portion input shaft 25. The two disc-shaped eccentric members 25a and 25b are provided with a 180 ° phase change in the circumferential direction in order to cancel each other the vibrations generated by the centrifugal force due to the eccentric motion. The motor output 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.

  The speed reduction part B includes a speed reduction part casing 22b, an outer pin holding part 45 included in the speed reduction part casing 22b, a speed reduction part input shaft 25, eccentric members 25a and 25b coupled to the speed reduction part input shaft 25, and an eccentric member 25a. 25b, curved plates 26a, 26b as revolving members rotatably supported, a plurality of outer pins 27 as outer peripheral engaging members engaged with outer peripheral portions of the curved plates 26a, 26b, and a wheel side rotating member 28. And the inner pin 31 serving as an inner engagement member that is coupled to the wheel-side rotating member 28 and extracts the rotational movement of the curved plates 26a and 26b, and attached to the clearance between the curved plates 26a and 26b. A center collar 29 that abuts the end face to prevent the curved plate from tilting and a reinforcing member 61 are provided.

  The wheel side rotation member 28 includes a flange portion 28a and a shaft portion 28b. 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 is fixed to the outer diameter surface of the shaft portion 28b.

  Referring to FIG. 2, the curved plate 26 b has a plurality of curved concave portions that are configured by trochoidal curves such as epitrochoids and are recessed in the radial direction on the outer peripheral portion, and a plurality of curved plates that penetrate from the one side end surface to the other side end surface. Through-holes 30a and 30b. A plurality of through holes 30a are provided at equal intervals on the circumference centering on the rotation axis X of the curved plate 26b, and receive the inner pins 31. The through hole 30b is provided at the center X of the curved plate 26b, and is the inner periphery of the curved plate 26b. The curved plate 26b is attached to the outer periphery of the eccentric member 25b so as to be relatively rotatable.

  A reinforcing member 61 is provided at the end 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 surface of the annular portion 61b to the motor portion A in the axial direction. Since the load applied to some of the inner pins 31 from the curved plates 26a and 26b is supported by all the inner pins 31 via the annular portion 61b, the stress acting on the inner pins 31 is reduced and the durability is improved. Can be made. The tip of the cylindrical portion 61 c is drivingly coupled to the oil pump 51.

  The curved plate 26b is rotatably supported by the rolling bearing 41 with respect to the eccentric member 25b. The rolling bearing 41 has an inner diameter surface fitted to the outer diameter surface of the eccentric member 25b, an inner ring member 42 having an inner raceway surface 42a on the outer diameter surface, and a through hole 30b that becomes the inner raceway surface 42a and the outer raceway surface. It is a cylindrical roller bearing provided with the some roller 44 arrange | positioned between these hole wall surfaces, and the holder | retainer (illustration omitted) holding the space | interval of the roller 44 adjacent in the circumferential direction. Alternatively, it may be a deep groove ball bearing. The inner ring member 42 further includes a hole 43 that is located on the inner raceway surface 42a and penetrates in the radial direction and a pair of flanges that face each other across the inner raceway surface 42a. The hole 43 is connected to the branch oil passage 58b of the eccentric member 25b. The same applies to the curved plate 26a.

  The oil pump 51 is connected to a suction oil passage 52 and a discharge oil passage 54 provided in the pump casing 22p, and sucks and discharges lubricating oil from an oil reservoir 53 provided in a lower portion of the speed reduction portion B via the suction oil passage 52. The lubricating oil is discharged from the oil passage 54. The discharge oil passage 54 includes a cooling oil passage 55 that is provided in the motor casing 22a to cool the lubricating oil, a communication oil passage 56 that is provided in the motor cover 22t, a tubular motor output shaft 35, and a speed reduction unit input shaft 25. An axial oil passage 57 provided in the interior and extending along the axis O, and a deceleration portion B, similarly extend in the branch oil passage 58a and the eccentric member 25b extending radially outward from the axis O in the eccentric member 25a. The branch oil passage 58b and the holes 43 formed in the inner ring member 42 fitted to the outer peripheries of the eccentric members 25a and 25b are sequentially connected.

  The lubricating oil discharged from the oil pump 51 sequentially flows through these oil passages 54, 55, 56, 57, 58 a, 58 b and the hole 43, and the inside of the speed reduction part B (curved plates 26 a and 26 b and their inner ring members 42). The inner raceway surface 42a and the like). The lubricating oil after lubrication falls and collects in the oil reservoir 53. Then, it is sucked again by the oil pump 51 and circulates inside the in-wheel motor drive device 21.

  A plurality of outer pins 27 are provided at equal intervals on a circumferential track centering on the rotation axis O of the motor side rotating member. When the curved plates 26a and 26b revolve, the outer circumferential curved concave portion and the outer pin 27 engage with each other to cause the curved plates 26a and 26b to rotate.

  The outer pin 27 disposed inside the casing 22 may be directly held by the speed reduction unit casing 22b. However, the outer pin 27 is preferably fitted to the outer pin holding part 45 fitted and fixed to the inner wall of the speed reduction unit casing 22b. Is retained. 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 26a, 26b 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 diameter surface of the bearing casing 22 c, and its inner ring is fitted and fixed to the outer diameter surface of the wheel hub 32. The wheel hub 32 has a cylindrical hollow portion 32a and a flange portion 32b. A drive wheel road wheel (not shown) is fixedly connected 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.

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

  Accordingly, when the motor output shaft 35 connected to the rotor 24 rotates, the curved plates 26a and 26b revolve around the rotation axis O of the motor side rotation member. At this time, the outer pin 27 is engaged with the curved concave portions formed on the outer circumferences of the curved plates 26a and 26b while rolling, and rotates the curved plates 26a and 26b in the direction opposite to the rotation of the motor side rotating member. Exercise.

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

  At this time, the wheel-side rotating member 28 disposed coaxially with the axis O takes out the rotation of the curved plates 26 a and 26 b as the output shaft of the speed reduction unit B. 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.

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

  In this way, by adopting the speed reduction unit B that can obtain a large speed reduction ratio without using a multi-stage configuration, the in-wheel motor drive device 21 having a compact and high speed reduction ratio can be obtained. Since 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 26a and 26b of the inner pin 31, the frictional resistance is reduced. The transmission efficiency of the deceleration part 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, two curved plates 26a and 26b of the speed reduction portion B are provided with 180 ° phase shifts. However, the number of the curved plates can be arbitrarily set. In the case of providing a sheet, it is preferable to change the phase by 120 °.

  Moreover, although the motion conversion mechanism in a present Example showed the example comprised by the inner pin 31 fixed to the wheel side rotation member 28, and the through-hole 30a provided in the curve boards 26a and 26b, Without limitation, any configuration capable of transmitting the rotation of the speed reduction unit B to the wheel hub 32 can be employed. 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 outer pin holding part 45 will be described in detail.

FIG. 3 is a front view showing a partial cross section of the outer pin holding portion viewed from the wheel hub bearing portion C side in the direction of the axis O. FIG. FIG. 4 is a view in which a part of the cross section taken along the line IV-IV in FIG. Referring to FIGS. 3 and 4, the outer pin holding portion 45 includes a cylindrical tubular portion 46 and ring portions 47 and 48 that protrude radially inward from both axial ends of the tubular portion 46. Prepare. The inner diameter of the ring portion 47 is smaller than the inner diameter D ₄₈ of the ring portion 48. Further, the inner diameter D ₄₈ of the ring portion 48 is larger than the outer diameter of the curved plates 26 a and 26 b, and the curved plates 26 a and 26 b can pass through the ring portion 48. An engaging groove 50 extending in the circumferential direction about the axis O is provided at the boundary with the ring portion 48 in the inner periphery of the cylindrical portion 46. The engaging groove 50 engages with outer ring locking members 65 and 75 described later.

  The ring portion 47 is provided with a plurality of outer pin holding holes 47a penetrating in the direction of the axis O. The ring portion 48 is provided with a plurality of notches 48k penetrating in the direction of the axis O. The notch 48k has an arc shape and is continuous with the outer pin holding hole 47a. The outer pin holding hole 47a and the notch 48k hold the outer ring 27g of the needle roller bearing 27a. When the outer pin holding part 45 is attached to the casing 22, the continuously extending holding hole 47 a and the notch part 48 k are parallel to the rotational axis O of the speed reducing part input shaft 25.

  As shown in FIG. 4, the inner periphery of the ring portion 47 is formed such that the inner diameter on the outer side in the axis O direction is larger than the inner inner diameter. 49 is provided.

  FIG. 5 is a longitudinal sectional view showing a state in which the outer ring 27g of the needle roller bearing 27a is attached to the outer pin holding part 45 and the curved plates 26a and 26b are accommodated inside the outer pin holding part 45. . FIG. 6 is a rear view showing a state in which the outer pin holding portion 45 in the middle of assembling to which the outer ring 27g is not yet attached is viewed in the direction of the arrow VI in FIG. FIG. 7 is a view showing a state in which the outer pin holding portion 45 to which the needle roller bearing 27a is attached is taken as a cross section taken along the line VII-VII in FIG. The outer pin holding hole 47a has substantially the same size as the outer periphery of the outer ring 27g, and both are fixed by intermediate fitting. The notch 48k is also approximately the same size as the outer periphery of the outer ring 27g, and both are fixed by an intermediate fit.

  As shown in FIG. 6, the cutout portion 48k has an arc shape in cross section, and the angle range forming the arc exceeds 180 degrees. Then, as shown in FIG. 7, the outer ring 27g is closely fitted to the outer circumference exceeding 180 degrees in the circumferential direction. Thus, since the notch 48k has an arc shape exceeding 180 degrees, the outer ring 27g can be gripped, and the outer ring 27g does not come off in the inner diameter direction.

  The outer pin holding part 45 includes an outer ring locking member 65 that is attached to the inner end surface 48i of the ring part 48 and restricts the movement of the outer ring 27g inward in the axis O direction. 8 is a front view of the outer ring locking member 65, and FIG. 9 is a side view showing the outer ring locking member 65 as viewed in the direction of the arrow IX in FIG. The outer ring locking member 65 has an arc shape extending in the circumferential direction of the ring portion 48, and more specifically has a C shape with a part of the circumferential direction cut away. A gap 66 having a width smaller than the distance between the adjacent outer pins 27 and 27 is formed between the separated ends. During assembly, the outer ring locking member 65 is elastically deformed in a direction to close the gap 66, whereby the outer ring locking member 65 is reduced in diameter, and the outer ring locking member 65 can be easily placed on the inner periphery of the ring portion 48. it can.

  The outer ring locking member 65 is a belt-like body as shown in FIG. 8 and is flat as shown in FIG. 9, and is attached to the inner end surface 48 i of the ring portion 48 so that the flat surface is perpendicular to the axis O.

  Further, the outer ring locking member 65 has the same number of locking portions 67 as the outer pin 27 located along the annular end surface 27gi of the outer ring 27g. The locking portions 67 are arranged at the same interval as the interval between the adjacent outer pins 27, 27. Adjacent locking portions 67 and 67 are integrally coupled with the axis O and the arc-shaped connecting portion 68 centered on the axis O. Therefore, when viewed in the direction of the axis O, the locking portion 67 looks like a petal. The outer ring locking member 65 that becomes an aggregate looks like a flower in which petals are regularly arranged. The locking portion 67 has a semicircular shape that contacts half of the annular end surface 27gi of the outer ring 27g.

  Further, the locking portion 67 forms a semicircular arc cutout 67k through which the outer pin 27 passes. That is, the inner diameter of the circular arc cut 67k is larger than the outer diameter of the outer pin 27. With the outer ring locking member 65 attached to the ring portion 48, the locking portion 67 is positioned on the outer diameter side with respect to the outer pin 27 as viewed from the axis O. The outer ring 27 g is restricted from moving in the direction of the axis O in the outer pin holding portion 45 by the locking portion 67 of the outer ring locking member 65. Furthermore, as shown in FIG. 7, by setting the inner diameter of the circular arc notch 67k to be smaller than the inner diameter of the outer ring 27g, the plurality of needle rollers of the needle roller bearing 27a can be restricted from moving inward in the axis O direction. it can.

  An outer ring locking member 71 having a shape different from that of the outer ring locking member 65 described above is attached to the ring portion 47. FIG. 10 is a front view showing a state in which the other outer ring locking member 71 is viewed from the direction of the axis O, and in order to facilitate understanding, the ring portion 47 fitted to the outer ring locking member 71 is indicated by a broken line. . 11 is a longitudinal sectional view showing a section taken along line XI-XI in FIG. FIG. 12 is an enlarged view of the cross section shown in FIG.

  As shown in FIG. 10, the outer ring locking member 71 has a cylindrical shape with a cylindrical portion 71t and a flange portion 71f formed at the end of the cylindrical portion 71t in the axis O direction, and has a ring shape. It is attached coaxially with the axis O of the input shaft 25. The flange portion 71f protrudes outward in the radial direction from the tubular portion 71t. The cylindrical portion 71t is provided with a plurality of claw portions 71n at predetermined intervals in the circumferential direction by punching or the like. The claw portion 71n has a toe slightly protruding radially outward and can be elastically deformed radially inward.

  5, the outer ring 27g of the needle roller bearing 27a is attached to the outer pin holding hole 47a of the ring portion 47, and then the outer ring locking member 71 is moved from the ring portion 48 into the outer pin holding portion 45 as shown in FIG. Insert. Then, the tubular portion 71t of the outer ring locking member 71 is inserted into the inner periphery of the ring portion 47, and the claw portion 71n is fitted to the step 49, so that the outer ring locking member 71 is fixed so as not to move relative to the axis O direction. The

  As a result, the flange portion 71f contacts the outer ring 27g and restricts the movement of the outer ring 27g inward in the axis O direction. Even when the outer diameter surface of the outer ring 27g that is intermediately fitted in the outer pin holding hole 47a is weak in the radial compressive force received from the inner diameter surface of the outer pin holding hole 47a, the flange portion 71f is thus externally attached. The outer ring 27g of the needle roller bearing 27a can be prevented from coming out of the outer pin holding part 45 of the casing 22 by contacting the inner wall of the pin holding part 45 and pressing the end of the outer ring 27g in the axial direction. Since both ends of the outer pin holding portion 45 in the axis O direction are connected to the casing 22, the outer ring 27g does not come out of the outer pin holding portion 45 outward in the axis O direction.

  In the subsequent assembly operation, the curved plate 26b, the center collar 29, and the curved plate 26a are sequentially inserted from the ring portion 48 into the outer pin holding portion 45. Since these outer diameters are smaller than the inner diameter of the ring portion 48, they can pass through the ring portion 48. Next, the outer ring locking member 65 is inserted from the ring part 48 into the outer pin holding part 45. The outer peripheral edge of the connecting portion 68 of the outer ring locking member 65 is engaged and fixed with the engaging groove 50 of the outer pin holding portion 45. Further, as shown in FIG. 7, the locking portion 67 is accommodated in the cutout portion 48 k on the inner periphery of the cylindrical portion 46. As a result, the outer ring locking member 65 does not rotate inside the outer pin holding portion 45.

  Next, the outer ring 27g and the outer pin 27 are inserted into the notch 48k from the outside in the axis O direction, and the rollers of the bearing 27a are also arranged. Since the annular end surface 27gi of the outer ring 27g comes into contact with the locking portion 67, the movement of the outer ring 27g inward in the axis O direction is restricted.

  Next, another embodiment of the present invention will be described. FIG. 13 is a longitudinal sectional view showing a state in which the outer ring locking member according to another embodiment is attached to the outer pin holding part, with a part omitted, and FIG. 14 is an assembly in which the outer ring 27g is not yet attached. It is a rear view which shows the state which looked at the outer pin holding | maintenance part 45 in the middle in the direction of arrow XIV of FIG. FIG. 15 is a diagram illustrating a state in which the outer pin holding portion 45 to which the bearing 27a is attached is cut along XV-XV in FIG. 13 and viewed in the direction of the arrow. 16 is a front view of the outer ring locking member 75, and FIG. 17 is a side view of the outer ring locking member 75 as viewed in the direction of arrow XVII in FIG.

  Regarding the other embodiments, the same components as those in the above-described embodiments will be denoted by the same reference numerals, the description thereof will be omitted, and different configurations will be described below.

  In another embodiment, the outer ring locking member 75 is attached to the inner end surface 48i of the ring portion 48 to restrict the movement of the outer ring 27g toward the inner side in the axis O direction. The outer ring locking member 75 has a C shape in which a part of the circumferential direction is cut off in the circumferential direction of the ring portion 48, and one end thereof is bent at a right angle. The bent portion 78 extends in the axis O direction. Further, the inner end face 48 i of the ring portion 48 is formed with a notch groove 79 cut from the inner periphery toward the outer diameter direction, and the notch groove 79 engages with the bent portion 78.

  As shown in FIG. 15, the locking portion 77 is not accommodated in the cutout portion 48k on the inner periphery of the cylindrical portion 46, and the outer ring locking member may rotate during assembly if it remains as it is. However, in this embodiment, the outer ring locking member 75 has a bent portion 78 directed toward the inner end surface 48i, and the bent portion 78 engages with the notch groove 79, thereby preventing the outer ring locking member 75 from rotating. be able to.

  The outer ring locking member 75 includes a plurality of locking portions 77 at the same circumferential interval as the outer pin 27. For this reason, the outer ring | wheel latching member 75 becomes a flower-like shape centering on the direction of the axis O by using the latching | locking part 77 as a petal. The locking portion 77 has a semicircular shape that contacts half of the annular end surface 27gi of the outer ring 27g.

  Further, the locking portion 77 forms a semicircular arc cutout 77k through which the outer pin 27 passes. With the outer ring locking member 75 attached to the ring portion 48, the locking portion 77 is arranged between the axis O and the outer pin 27. The outer ring 27g is restricted from moving in the direction of the axis O in the outer pin holding portion 45 by the locking portion 77 of the outer ring locking member 75.

  By the way, according to the above-described embodiments, the in-wheel motor drive device 21 includes the cylindrical portion 46 coaxial with the axis O, and the ring portions 47 and 48 protruding in the inner diameter direction from both ends of the cylindrical portion 46, respectively. , The eccentric members 25a and 25b, the curved plates 26a and 26b, the outer pin 27, and the cylindrical outer pin holding portion 45 that accommodates the inner pin 31 therein. The outer pin 27 serving as the outer engagement member is supported by the ring portions 47 and 48 at both ends in the axis O direction. As a result, the outer pin 27 can be held in parallel with the rotation axis O of the speed reducer input shaft 25, and the assembly work is easy. Since the outer pin holding hole 47a and the notch 48k can be formed simultaneously by simultaneous processing, it is relatively easy to make them continuous.

  Further, since the inner diameter of one of the ring portions 48 is larger than the outer diameters of the curved plates 26a and 26b, a curved plate having a larger outer diameter can be easily inserted into the outer pin holding portion 45, and the assembling work is easy. .

  The outer ring 27g serving as the end of the outer engagement member has a circular cross-sectional shape, and the ring part 48 has an arc-shaped cutout part 48k fitted to the outer ring 27g on the inner periphery, and the arc of the cutout part 48k. Since the portion is closely fitted to the outer periphery of the outer ring 27g that exceeds 180 degrees in the circumferential direction, the outer ring 27g can be gripped on a plane perpendicular to the axis O. In addition, the outer ring 27g can be inserted into the ring portion in the axial direction, and the assembly efficiency is improved.

  Further, according to these embodiments, the outer engagement member extends in the direction of the axis O, the outer pin 27, the outer ring 27g surrounding the outer peripheral surface of the outer pin 27 at both ends of the outer pin 27, the outer ring 27g and the outer pin. Since there are a plurality of rollers of the bearing 27a disposed in the annular gap with the outer pin 27, the outer pin 27 can be rotatably supported by the rolling bearing 27a. Therefore, the friction when the curved plates 26a and 26b come into contact with the outer pin 27 can be remarkably reduced, and the power transmission efficiency of the speed reducing portion B can be improved.

  Further, according to these embodiments, the outer pin holding portion 45 includes the outer ring locking members 65 and 75 that are attached to the inner end surface 48i of the ring portion 48 and restrict the movement of the outer ring 27g toward the inner side in the axis O direction. Thus, even when the outer pin 27 is rotatably supported by the rolling bearing 27a, the outer ring 27g of the rolling bearing 27a can be prevented from coming out of the ring portion 48. Although not shown, the outer ring locking members 65 and 75 may be attached to the ring portion 47 instead of the other outer ring locking member 71.

  Further, according to these embodiments, the outer ring locking members 65 and 75 have an arc shape extending in the circumferential direction of the ring portion 48, so that the one outer ring locking member 65 and 75 are arranged at equal intervals in the circumferential direction. The plurality of outer rings 27g can be fixed in the direction of the axis O, and the assembly efficiency is improved.

  Further, according to these embodiments, the outer ring locking members 65 and 75 are C-shaped with a part of the circumferential direction cut off, so that both ends of the C-shaped outer ring locking member are interposed via the gap 66. Facing each other. Accordingly, the outer ring locking member can be easily inserted into the outer pin holding portion 45 from the inner periphery of the ring portion 48 by elastically deforming the gap 66 so as to close during the assembly operation. Therefore, the assembly efficiency is improved.

  Further, according to these embodiments, the outer ring locking members 65 and 75 form the circular arc cutouts 67k and 77k through which the outer pin 27 passes and the locking parts 67 and 77 positioned along the annular end surface of the outer ring 27g. Are provided at predetermined intervals in the circumferential direction that are the same as those of the outer pins 27, so that the outer ring 27g can be suitably prevented from moving inward in the axis O direction.

  Further, according to these embodiments, the outer ring locking members 65 and 75 are flat belt-like bodies, and are attached to the ring portion so that the flat surface is perpendicular to the axis. The outer ring locking members 65 and 75 can be attached to the inner space of the outer pin holding portion 45 where the space restriction is severe and narrow.

  Further, according to these embodiments, the locking portions 67 and 77 are semicircular when viewed from the direction of the axis O, so that the outer ring 27g can be suitably prevented from moving inward in the direction of the axis O.

  The locking portion 67 of the outer ring locking member 65 is disposed on the radially outer side of the ring portion 48. Alternatively, the locking portion 77 of the outer ring locking member 75 is disposed radially inside the ring portion 48 and is arranged between the axis O and the outer pin 27. In the latter case, the outer ring locking member 75 has a bent portion 78 formed by bending one end in the circumferential direction, and the bent portion 78 engages with the notch groove 79 of the outer pin holding portion 45. Thereby, the rotation of the outer ring locking member 75 can be prevented.

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

It is a 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 front view which shows the outer pin holding | maintenance part of the Example seen from the wheel hub bearing part side in the axial direction in a partial cross section. It is a figure which abbreviate | omits and shows some cross sections in IV-IV of FIG. It is a longitudinal cross-sectional view which abbreviate | omits and shows the state which attached the outer ring | wheel of the needle roller bearing to the outer pin holding part of the Example, and accommodated the curved board inside the outer pin holding part. It is a rear view which shows the state which looked at the direction of the arrow VI of FIG. 5 in the outer pin holding | maintenance part in the middle of an assembly in which the outer ring is not yet attached. It is a figure which shows the state which made the outer pin holding | maintenance part to which the bearing was attached the cross section by VII-VII of FIG. 5, and was seen from the direction of the arrow. It is a front view of the outer ring | wheel latching member of the Example. It is a side view which shows the state which looked at the outer ring | wheel latching member of the Example in the direction of the arrow IX of FIG. It is a longitudinal cross-sectional view which shows the state by which the other outer ring latching member was attached to the inside of a casing. It is a longitudinal cross-sectional view which shows the cross section in XI-XI of FIG. It is the figure which expanded the cross section shown in FIG. It is a longitudinal cross-sectional view which abbreviate | omits and shows the state in which the outer ring latching member which becomes another Example was attached to the outer pin holding | maintenance part. It is a rear view which shows the state which looked at the direction of the arrow XIV of FIG. 13 for the outer pin holding | maintenance part in the middle of the assembly in which the outer ring is not yet attached. It is a figure which shows the state which cut | disconnected the outer pin holding part to which the bearing was attached by XV-XV of FIG. 13, and looked at the direction of the arrow. It is a front view of the outer ring | wheel latching member of the Example. It is a side view which shows the state which looked at the outer ring | wheel latching member of the Example in the direction of arrow XVII of FIG.

Explanation of symbols

  21 in-wheel motor drive device, 22 casing, 23 stator, 24 rotor, 25 speed reducer input shaft, 25a, 25b eccentric member, 26a, 26b curved plate, 27 outer pin, 27a needle roller bearing, 27g outer ring, 28 wheel side Rotating member, 29 Center collar, 30a, 30b Through hole, 31 Inner pin, 31a Needle roller bearing, 32 Wheel hub, 33 Wheel hub bearing, 35 Motor output shaft, 45 Outer pin holding part, 46 Cylindrical part, 47, 48 ring part, 47a outer pin holding hole, 48k notch part, 49 step, 65 outer ring locking member, 67 locking part, 67k arc notch, 71 outer ring locking member, 71t cylindrical part, 71f flange part, 71n Claw part, 75 outer ring locking member, 77 locking part, 77k arc cutout, 78 bent part.

Claims (11)

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 reduction portion is a disc-shaped eccentric member that is eccentric from the axis of the motor-side rotating member and is coupled to one end of the motor-side rotating member;
A curved plate having an inner periphery attached to the outer periphery of the eccentric member so as to be relatively rotatable, an outer periphery formed of a wavy curve, and having a plurality of curved concave portions recessed in the radial direction;
A plurality of outer circumferentially arranged members arranged at equal intervals in the circumferential direction around the axis, and engaged with the curved recess as the eccentric member rotates, and revolves and rotates the curved plate;
An inner engagement member that is coupled to the wheel-side rotation member and engages with a hole provided between an outer periphery of the curved plate and the axis;
A cylindrical portion disposed coaxially with the axis, and ring portions protruding in an inner diameter direction from both ends of the cylindrical portion, the eccentric member, the curved plate, the outer engagement member, and the inner engagement A cylindrical outer engagement member holding portion for accommodating the member inside,
The outer engagement member extends in parallel with the axis, with both axial ends supported by the ring portions, respectively.
An in-wheel motor drive device, wherein an inner diameter of at least one of the ring portions is larger than an outer diameter of the curved plate. The end of the outer engagement member has a circular cross-sectional shape,
The at least one ring portion has an arc-shaped cutout portion that fits with an end portion of the outer engagement member on an inner periphery,
2. The in-wheel motor drive device according to claim 1, wherein the arc portion of the notch is in close contact with an outer periphery exceeding 180 degrees in the circumferential direction of the outer periphery of the axial end portion of the outer engagement member.   The outer engagement member includes an outer pin extending in the axial direction, an outer ring surrounding an outer peripheral surface of the outer pin at both ends of the outer pin, and a plurality of rolling elements disposed in an annular gap between the outer ring and the outer pin. The in-wheel motor drive device of Claim 1 or 2 which has these.   4. The in-wheel motor drive device according to claim 3, wherein the outer engagement member holding portion includes an outer ring locking member that is attached to an inner end surface of the ring portion and restricts movement of the outer ring toward an inner side in an axial direction.   The in-wheel motor drive device according to claim 4, wherein the outer ring locking member has an arc shape extending in a circumferential direction of the ring portion.   The in-wheel motor drive device according to claim 5, wherein the outer ring locking member has a C shape with a part in the circumferential direction cut away.   The outer ring locking member has a circular arc cutout through which the outer pin passes and includes locking portions positioned along the annular end surface of the outer ring at the same circumferential predetermined interval as the outer engagement member. The in-wheel motor drive device according to claim 6.   The in-wheel motor drive device according to claim 7, wherein the outer ring locking member is a flat belt-like body, and is attached to the ring portion so that the flat surface is perpendicular to the axis.   The in-wheel motor drive device according to claim 8, wherein the locking portion has a semicircular shape when viewed from the axial direction.   The in-wheel motor drive device according to claim 9, wherein the locking portion is arranged between the axis and the outer pin.   The in-wheel motor drive device according to claim 10, wherein the outer ring locking member is bent at one end in the circumferential direction to engage with the outer engagement member holding portion.

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