JP2015183831A - in-wheel motor drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-wheel motor drive device that is excellent in durability with high reliability by reducing influence of misalignment of an outer pin holding hole 54 holding both ends of an outer pin 32.SOLUTION: A pair of division plates 50a, 50b enabling mutually relative motion on the inner diameter surface of a casing 22b of a speed reducer B is arranged, the outer pin holding hole 54 holding both ends of the outer pin 32 is provided in the pair of division plates 50a, 50b enabling mutually relative motion, and thereby the position of the outer pin holding hole 54 holding both ends of the outer pin 32 is aligned.

Description

  This invention eliminates inaccuracy of the outer pin holding hole that supports both ends of the outer pin that meshes with the corrugated tooth profile on the outer periphery of the curved plate in the cycloid reduction gear used in the in-wheel motor drive device, and is excellent in durability. The present invention relates to a highly reliable in-wheel motor drive device.

  As shown in FIG. 15, the in-wheel motor drive device 121 includes a motor unit A that generates a driving force, a speed reducer B that decelerates and outputs the rotation of the motor unit A, and an output from the speed reducer B as driving wheels. And a wheel hub C to be transmitted to the vehicle.

  The motor part A and the speed reducer B are accommodated in the casing 122. The casing 122 includes a casing 122a on the motor part A side and a casing 122b on the reduction gear B side.

  The motor part A uses a radial gap type of which a stator 123 is provided on the inner peripheral surface of the casing 122a and a rotor 124 is provided at an interval on the inner periphery of the stator 123.

  The rotor 124 has a motor shaft 124a in the center. The motor shaft 124a is connected to the input shaft 130 of the speed reducer A and is inserted into the casing 122b of the speed reducer B. The bearings 125a and 125b are connected to the casing 122a. And is supported rotatably.

  The casing 122b of the speed reducer B is provided with an oil tank 141 for lubricating oil at the lower portion. The lubricating oil in the oil tank 141 is sucked by the oil pump 142, and the lubricating oil is supplied to the motor unit A and the speed reducer B for lubrication. And cooling is performed (Patent Document 1).

  An oil supply passage 143 that supplies lubricating oil to the inside of the speed reducer B extends along the inside of the casing 122a from the discharge port of the oil pump 142 that is driven by using the output rotation of the speed reducer B that decelerates the rotation of the motor unit A. And a passage extending from the rear of the casing 122a through the internal passage 144 of the motor shaft 124a and the internal passage 145 of the input shaft 130 of the speed reducer B into the casing 122b of the speed reducer B.

  The lubricating oil return passage 146 is configured by a passage that reaches the suction port of the oil pump 142 through the discharge port 147 and the oil tank 141 provided at the bottom of the casing 122b of the speed reducer B.

  As shown in FIGS. 15 to 17, the cycloid reduction gear B supports two curved plates 131 rotatably by eccentric shaft portions 130 a and 130 b provided on the input shaft 130, and these curved plates 131. Is engaged with the outer pin 132 supported on the inner side of the outer pin housing 150 located on the inner diameter surface of the casing 122b of the reduction gear B via a gap, and the input shaft 130 is rotated. The curved plate 131 is eccentrically oscillated, the rotation of the curved plate 131 is output from the output shaft 133 arranged coaxially with the input shaft 130, and the wheel hub C is rotated.

  The number of outer pins 132 supported on the inner side of the outer pin housing 150 is larger than the corrugated tooth profile 131 a on the outer periphery of the curved plate 131.

  The outer pin 132 is supported by the outer pin housing 150 located on the inner diameter surface of the casing 122b of the reduction gear B via a gap. The outer pin housing 150 is floatingly supported by floating bolts (not shown) on the outer side and the inner side with respect to the casing 122b of the speed reducer B.

  As shown in FIGS. 18 and 19, the outer pin housing 150 has a cylindrical shape having a pair of flange portions 151 on the inner diameter side of both end faces in the axial direction.

  As shown in FIG. 15, one end of the input shaft 130 is connected to the motor shaft 124a of the rotor 124 by spline fitting and is driven to rotate by the motor portion A, and the other end is an eccentric shaft. Parts 130a and 130b are provided.

  A pair of eccentric shaft portions 130a and 130b are provided in the axial direction of the input shaft 130, as shown in FIG. The pair of eccentric shaft portions 130a and 130b is provided such that the center of the cylindrical outer diameter surface is 180 degrees out of phase in the circumferential direction, and rolls to the outer diameter surface of each of the pair of eccentric shaft portions 130a and 130b. A bearing 134 is fitted.

  The input shaft 130 provided with the pair of eccentric shaft portions 130a and 130b is provided with a pair of counterweights 135 with a 180 ° phase shift in the circumferential direction so as to sandwich the pair of eccentric shaft portions 130a and 130b.

  As shown in FIGS. 16 and 17, the curved plate 131 is rotatably supported by the input shaft 130 by a rolling bearing 134, and the corrugated tooth profile 131a formed on the outer periphery thereof is a trochoidal curved tooth profile. As shown in FIG. 17, in the curved plate 131, a plurality of pin holes 136 are formed at equal intervals on one circle centered on the rotation axis, and each of the pair of pin holes 136 aligned in the axial direction is formed in the curved plate 131. The pin 137 is inserted with a margin, and a part of the outer periphery of the roller bearing 137 a rotatably supported by the inner pin 137 is in contact with a part of the inner periphery of the pin hole 136.

  As shown in FIG. 16, the speed reducer B includes a curved plate 131 as a revolving member that is rotatably held by the eccentric shaft portions 130 a and 130 b, and a plurality of engaging gears 131 a on the outer peripheral portion of the curved plate 131. An outer pin 132, an output shaft 133 that outputs the rotation of the curved plate 131, a center collar 138 that is attached to a gap between the curved plates 131 and abuts against the end surfaces of the curved plates 131 to prevent the curved plate 131 from tilting; Is provided.

  The output shaft 133 has a flange portion 133a and a shaft portion 133b. As shown in FIGS. 16 and 17, inner pins 137 are fixed to the flange portion 133 a at equal intervals on a circumference centered on the rotation axis of the output shaft 133. A wheel hub C is disposed on the outer diameter surface of the shaft portion 133b so that torque can be transmitted by serration (or spline). The flange portion 133a and the stabilizer 133d are connected via the plurality of inner pins 137, and the output shaft 133 and the stabilizer 133d rotate integrally. A pump drive shaft 133c connected to the inner rotor of the oil pump 142 is integrally provided at the end of the stabilizer 133d on the motor part A side.

  As shown in FIG. 17, the outer pins 132 are provided at equal intervals on the circumferential orbit of the rotation axis of the input shaft 130. When the curved plate 131 revolves, the corrugated tooth profile 131a on the outer periphery engages with the outer pin 132 to cause the curved plate 131 to rotate.

  As shown in FIG. 16, an output shaft 133 and a stabilizer 133 d are rotatably supported via bearings 190 on the inner periphery of the flange portion 151 of the outer pin housing 150. An inner diameter surface of the flange portion 133a and the stabilizer 133d of the output shaft 133 and an outer diameter surface of the input shaft 130 are supported through a bearing 191 so as to be relatively rotatable.

  The curved plate 131 is incorporated between the flange portion 133a and the stabilizer 133d facing the output shaft 133. Further, both ends of the inner pin 137 penetrating the pin hole 136 of the curved plate 131 are supported by the flange portion 133a and the stabilizer 133d facing the output shaft 133.

  The plurality of inner pins 137 supported by the flange portions 133a opposed to the output shaft 133 are provided at equal intervals on a circumferential track centering on the rotation axis of the input shaft 130, thereby reducing the frictional resistance with the curved plate 131. For this purpose, a needle roller bearing 137a is provided at a position where it abuts against the inner wall surface of the pin hole 136 of the curved plate 131. The inner diameter dimension of the pin hole 136 is set to be larger than the outer diameter dimension of the inner pin 137 by a predetermined amount.

  As shown in FIG. 15, the wheel hub C includes an inner ring member 181 fitted and connected to the outer diameter surface of the shaft portion 133 b of the output shaft 133 so that torque can be transmitted by serration (or spline), and an inner ring member 181. And an outer ring member 182 that is rotatably held with respect to the casing 122b. The inner ring member 181 and the outer ring member 182 constitute a double row angular ball bearing, and a double row rolling element 183 is installed between the inner ring member 181 and the outer ring member 182. The inner ring member 181 is integrally provided with a wheel mounting flange portion 184.

  The outer pin 132 is not directly held by the casing 122b, but is held by an outer pin housing 150 supported in a floating state on the inner diameter surface of the casing 122b, as shown in FIG.

  Further, as shown in FIGS. 18 and 19, a slit 153 is provided in the lower portion of the cylindrical outer pin housing 150.

  The pair of flange portions 151 of the outer pin housing 150 are provided with a plurality of outer pin holding holes 154 penetrating in the thickness direction. As shown in FIG. 16, the outer pin holding hole 154 extends in a direction parallel to the rotation axis of the input shaft 130 and holds both ends of the outer pin 132. Both ends of the outer pin 132 are supported by the outer pin holding hole 154 via needle roller bearings 155. The needle roller bearing 155 includes an outer ring 155a and needle rollers 155b having the inner peripheral surface of the outer ring 155a and the outer peripheral surface of the outer pin 132 as rolling surfaces. The outer ring 155 a of the needle roller bearing 155 is fitted to the inner surface of the outer pin holding hole 154.

  Further, the corresponding outer pin holding holes 154 of the pair of flange portions 151 are provided at the same position in the circumferential direction so as to face each other. That is, the central axes of the pair of outer pin holding holes 154 coincide with each other, and when the outer pin housing 150 is attached to the casing 122b of the speed reducer B, the central axis of the outer pin holding holes 154 becomes the rotation axis of the input shaft 130. Become parallel.

  As shown in FIG. 18, a thick portion is formed on the inner diameter side of the pair of flange portions 151. A groove-shaped counterbore 157 is formed on the outer diameter surface of the thick portion so as to be continuous with the outer pin holding hole 154.

  As shown in FIG. 16, an outer pin side plate 158 that prevents the outer pin 132 inserted into the outer pin holding hole 154 from coming out in the axial direction is formed on the outer side surface portion located on the outer peripheral side in the radial direction of the pair of flange portions 151. Is fixed.

  In addition, a member that holds both ends of the outer pin 132 without using the outer pin housing 150 is disposed on the inner diameter surface of the casing 122b of the reduction gear B (Patent Document 2), or a member that holds both ends of the outer pin 132. In order to simplify the processing, a plate-shaped ring member that holds both ends of the outer pin 132 is also connected (Patent Document 3).

JP 2012-97903 A JP 2009-52630 A JP 2012-97765 A

  By the way, the outer pin holding hole 154 for holding both ends of the outer pin 132 is conventionally formed by a plate-shaped ring member held on the inner surface of the outer pin housing 150 or the casing 122b of the speed reducer B. The hole position is provided at a fixed position.

  Accordingly, if the positional accuracy of the hole position of the outer pin holding hole 154 is poor or the assembly accuracy or processing accuracy of the member provided with the outer pin holding hole 154 is poor, the misalignment of the outer pin 132 held in the outer pin holding hole 154 As a result, a part with a large load is generated, which may cause damage to the outer pin 132 and the curved plate 131, and may cause sound and vibration when the cycloid reduction gear is driven.

  Accordingly, an object of the present invention is to provide a highly reliable in-wheel motor drive device that is excellent in durability by reducing the influence of the misalignment of the outer pin holding hole that holds the outer pin.

  In order to solve the above problems, in the present invention, a motor unit that generates a driving force, a speed reducer that decelerates and outputs the rotation of the motor unit, and a wheel hub that transmits the output from the speed reducer to the drive wheels. An input shaft that is rotationally driven by the motor unit, a curved plate that is rotatably supported on the input shaft by an eccentric shaft portion provided on the input shaft, and has a corrugated tooth profile formed on the outer periphery; An outer pin that meshes with the corrugated tooth profile on the outer periphery of the curved plate, and an outer pin holding hole that is provided on the inner diameter surface of the casing of the speed reducer and supports both ends of the outer pin through bearings. In the in-wheel motor drive device, which is a cycloid type speed reducer, wherein the plate is eccentrically oscillated and the rotation of the curved plate is output from an output shaft arranged coaxially with the input shaft. Machine case An in-wheel motor characterized in that a pair of split plates that can move relative to each other are arranged on the inner surface of the ring, and an outer pin holding hole that supports both ends of the outer pin via a bearing is formed in the split plate. Drive device.

  By providing a non-rotating member that can be elastically deformed between the pair of split plates and the inner diameter surface of the reducer casing, it is possible to reduce the vibration generated in the split plates being transmitted to the reducer casing. .

  Relative motion of the pair of divided plates is achieved by providing opposing recesses in the outer diameter surface of the pair of divided plates and the inner diameter surface of the casing of the speed reducer, and inserting a detent member into the recess with a gap therebetween. May be secured.

  Protrusions and recesses that fit into each other are provided on the outer diameter surface of the pair of split plates and the inner diameter surface of the casing of the speed reducer, and a gap is provided between the convex portions and the recesses, so that the relative movement of the pair of split plates is performed. It may be ensured.

  An interval holding pin that holds an axial interval between the pair of divided plates is provided, and a gap that allows relative movement of the pair of divided plates is provided between the interval holding pin and the pair of divided plates.

  In the in-wheel motor drive device according to the present invention, as described above, the pair of split plates that can move relative to each other are arranged on the inner diameter surface of the casing of the speed reducer, and the pair of split plates that can move relative to each other are arranged outside. Since the outer pin holding hole for holding both ends of the pin is provided, the position of the outer pin holding hole is aligned so that the bearing and the curved plate between the outer pin and the outer pin holding hole are evenly contacted. As a result, the load can be distributed by a plurality of outer pins, and the surface pressure between the outer pins and the curved plate can be lowered, so that it is possible to provide a highly reliable in-wheel motor drive device with excellent durability. .

  As described above, since the alignment effect of the position of the outer pin holding hole is obtained, the position accuracy of the outer pin holding hole provided in the divided plate can be relaxed, and the productivity is improved.

  By providing a non-rotating member that can be elastically deformed between the pair of split plates and the inner diameter surface of the reducer casing, it is possible to reduce the vibration generated in the split plates being transmitted to the reducer casing. .

  By providing an interval holding pin that holds the interval between the pair of divided plates in the axial direction, it is possible to prevent an excessive load from being applied to the rotating component disposed between the pair of divided plates.

It is a vertical front view of the in-wheel motor drive device concerning this invention. It is an expansion vertical front view of a reduction gear. It is a vertical side view along the DD line of FIG. It is an enlarged view of an oil pump. It is a perspective view in the state where both ends of the outer pin were fitted into a pair of split plates via bearings. It is an exploded view which shows the assembly procedure of the reduction gear which uses a pair of division | segmentation plate. It is a vertical front view which shows other embodiment of the in-wheel motor drive device which concerns on this invention. It is a side view along the EE line of the embodiment shown in FIG. It is a vertical front view which shows other embodiment of the in-wheel motor drive device which concerns on this invention. It is a vertical side view along the FF line of embodiment shown in FIG. It is a vertical front view which shows other embodiment of the in-wheel motor drive device which concerns on this invention. It is a vertical side view along the GG line of embodiment shown in FIG. It is a schematic plan view of the electric vehicle which has the in-wheel motor drive device of FIG. It is the figure which looked at the electric vehicle of FIG. 13 from back. It is a vertical front view which shows a prior art example. It is an expansion vertical front view of the reduction gear of a prior art example. It is a vertical side view along the HH line of FIG. It is a perspective view of the conventional outer pin housing. It is a longitudinal cross-sectional view of the conventional outer pin housing.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
As shown in FIG. 13, an electric vehicle 11 equipped with an in-wheel motor drive device according to an embodiment of the present invention includes a chassis 12, front wheels 13 as steering wheels, drive wheels (rear wheels) 14, left and right And an in-wheel motor drive device 21 that transmits a drive force to each of the drive wheels 14. As shown in FIG. 14, the drive wheel 14 is accommodated in the wheel housing 12a of the chassis 12, and is fixed to the lower part of the chassis 12 via a suspension device (suspension) 12b. As a mounting form of the in-wheel motor drive device 21, in addition to the rear wheel drive system shown in FIGS. 13 and 14, either the front wheel drive system or the four wheel drive system may be used.

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

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

  As shown in FIG. 1, the in-wheel motor drive device 21 includes a motor unit A that generates a driving force, a speed reducer B that decelerates and outputs the rotation of the motor unit A, and an output from the speed reducer B as driving wheels. The motor hub A and the speed reducer B are housed in the casing 22 and are mounted in the wheel housing 12a of the electric vehicle 11 as shown in FIG.

  The motor part A and the speed reducer B are accommodated in the casing 22. The casing 22 includes a casing 22a on the motor part A side and a casing 22b on the reduction gear B side.

  The motor part A uses a radial gap type in which a stator 23 is provided on the inner peripheral surface of the casing 22a, and a rotor 24 is provided at an interval on the inner periphery of the stator 23.

  The rotor 24 has a motor shaft 24a at the center, and the motor shaft 24a is connected to the input shaft 30 of the speed reducer B and is inserted into the casing 22b of the speed reducer B. And is supported rotatably.

  The casing 22b of the speed reducer B is provided with an oil tank 41 for lubricating oil at the lower portion, the lubricating oil in the oil tank 41 is sucked by the oil pump 42, and the lubricating oil is supplied to the motor unit A and the speed reducing device B for lubrication. And cooling.

  The oil supply passage 43 that supplies lubricating oil to the inside of the speed reducer B extends along the inside of the casing 22a from the discharge port of the oil pump 42 that is driven by using the output rotation of the speed reducer B that decelerates the rotation of the motor part A. The passage extends from the rear of the casing 22a through the internal passage 44 of the motor shaft 24a and the internal passage 45 of the input shaft 30 of the reduction gear B to the inside of the casing 22b of the reduction gear B. The lubricating oil supplied from the oil pump 42 is scattered by the centrifugal force and the pressure of the oil pump 42 from the radial supply port provided in the internal passage 45 of the input shaft 30 of the speed reducer B, and the speed reducer B The inside is lubricated and cooled. A so-called axial center lubrication system is adopted.

  The return passage 46 for the lubricating oil is constituted by a discharge port 47 provided at the bottom of the casing 22 b of the speed reducer B and a passage that reaches the suction port of the oil pump 42 through the oil tank 41.

  As shown in FIG. 4, the oil pump 42 includes an inner rotor 72 that rotates using the output rotation of the speed reducer B, an outer rotor 73 that rotates following the rotation of the inner rotor 72, a pump chamber 74, The cycloid pump includes a suction port 75 that communicates with the return passage 46 and a discharge port 76 that communicates with the oil supply passage 43.

  Inner rotor 72 has a tooth profile formed of a cycloid curve on the outer diameter surface. Specifically, the shape of the tooth tip portion 72a is an epicycloid curve, and the shape of the tooth gap portion 72b is a hypocycloid curve. The inner rotor 72 rotates integrally with the output shaft 33 of the speed reducer B.

  The outer rotor 73 has a tooth profile formed of a cycloid curve on the inner diameter surface. Specifically, the shape of the tooth tip portion 73a is a hypocycloid curve, and the shape of the tooth gap portion 73b is an epicycloid curve. The outer rotor 73 is rotatably supported by the pump case 77.

  The inner rotor 72 rotates around the rotation center c1. On the other hand, the outer rotor 73 rotates around a rotation center c2 different from the rotation center c1 of the inner rotor 72. Further, when the number of teeth of the inner rotor 72 is n, the number of teeth of the outer rotor 73 is (n + 1). In this embodiment, n = 5.

  A plurality of pump chambers 74 are provided in the space between the inner rotor 72 and the outer rotor 73. When the inner rotor 72 rotates using the rotation of the output shaft 33 of the speed reducer B, the outer rotor 73 rotates in a driven manner. At this time, since the inner rotor 72 and the outer rotor 73 rotate around different rotation centers c1 and c2, the volume of the pump chamber 74 continuously changes. As a result, the lubricating oil flowing in from the suction port 75 is pumped from the discharge port 76 to the oil supply passage 43.

  As shown in FIG. 1, the casing 22 b of the speed reducer B is provided with an oil tank 41 for lubricating oil at the lower portion. The lubricating oil in the oil tank 41 is sucked by the oil pump 42 through the return passage 46, and the motor unit A Lubricating oil is supplied to the reduction gear B to perform lubrication and cooling.

  As shown in FIGS. 1 to 3, the cycloid type speed reducer B rotatably supports two curved plates 31 by eccentric shaft portions 30 a and 30 b provided on the input shaft 30, and these curved plates 31. The corrugated tooth profile 31a formed on the outer periphery of the gear plate is engaged with the outer pin 32 disposed inside the casing 22b of the speed reducer B, and the curved plate 31 is caused to eccentrically swing by the rotation of the input shaft 30. The rotation of 31 is output from the output shaft 33 arranged coaxially with the input shaft 30, and the wheel hub C is rotated.

  The number of outer pins 32 disposed inside the casing 22 b of the reduction gear B is larger than the corrugated tooth profile 31 a on the outer periphery of the curved plate 31.

  As shown in FIGS. 1, 2, and 5, the outer pin 32 is formed on a pair of divided plates 50 a and 50 b that are disposed so as to be relatively movable with respect to each other through a gap on the inner diameter surface of the casing 22 b of the speed reducer B. It is supported. Outer pin holding holes 54 for supporting both ends of the outer pin 32 via bearings 55 are formed in the pair of divided plates 50 a and 50 b arranged so as to be capable of relative movement.

  FIG. 5 shows a state in which both end portions of the outer pin 32 are supported via the bearings 55 in the outer pin holding holes 54 of the pair of split plates 50a and 50b.

  As shown in FIGS. 2 and 5, the divided plates 50 a and 50 b are ring-shaped and have a thick portion 51 on the inner diameter side.

  The corresponding outer pin holding holes 54 of the pair of divided plates 50a and 50b are provided at the same position in the circumferential direction so as to face each other. That is, the pair of outer pin holding holes 54 are provided so that the central axes coincide with each other.

  The pair of split plates 50a and 50b are disposed through a gap on the inner surface of the casing 22b of the speed reducer B so that they can move relative to each other. The pair of split plates 50a and 50b can be elastically deformed such as rubber. A rotation preventing member 60 is used to prevent rotation on the inner diameter surface of the casing 22b of the speed reducer B.

  If the rotation preventing member 60 that can be elastically deformed is arranged on the inner diameter surface of the pair of split plates 50a and 50b and the casing 22b of the speed reducer B, vibration generated in the split plates can be reduced from being transmitted to the casing of the speed reducer. it can. Further, by forming the anti-rotation member 60 from a material that can be elastically deformed, the pair of divided plates 50a and 50b can move relative to the inner diameter surface of the casing 22b of the speed reducer B.

  When the pair of split plates 50a and 50b are arranged so as to be able to move relative to each other, the pair of split plates 50a and 50b are arranged so that the bearing 55 and the curved plate 31 between the outer pin 32 and the outer pin holding hole 54 are evenly contacted. The position of the outer pin holding hole 54 formed in 50b is aligned. Thereby, the load received from the curved plate 31 can be dispersed by the plurality of outer pins 32, and the surface pressure between the outer pin 32 and the curved plate 31 can be lowered, so that the durability is improved.

  In the embodiment shown in FIGS. 1, 2 and 5, the bearing 55 includes an outer ring 55 a, and needle rollers 55 b in which the inner peripheral surface of the outer ring 55 a and the outer peripheral surface of the outer pin 32 are rolling surfaces. The needle roller bearing which consists of is used.

  As shown in FIG. 1, one end of the input shaft 30 is connected to the motor shaft 24a of the rotor 24 by spline fitting and is driven to rotate by the motor portion A. The other end is an eccentric shaft. Portions 30a and 30b are provided.

  As shown in FIG. 2, a pair of eccentric shaft portions 30 a and 30 b are provided in the axial direction of the input shaft 30. The pair of eccentric shaft portions 30a and 30b is provided such that the center of the cylindrical outer diameter surface is 180 degrees out of phase in the circumferential direction, and rolls to the outer diameter surface of each of the pair of eccentric shaft portions 30a and 30b. A bearing 34 is fitted.

  The input shaft 30 provided with the pair of eccentric shaft portions 30a and 30b is provided with a pair of counterweights 35 with a 180 ° phase shift in the circumferential direction so as to sandwich the pair of eccentric shaft portions 30a and 30b.

  The curved plate 31 is rotatably supported on the input shaft 30 by the rolling bearing 34, and the corrugated tooth profile 31a formed on the outer periphery thereof is a trochoidal curved tooth profile. As shown in FIG. 3, the curved plate 31 has a plurality of pin holes 36 formed at equal intervals on a single circle centered on the rotation axis, and each of the pair of pin holes 36 aligned in the axial direction is formed inside each of the pin holes 36. The pin 37 is inserted with a margin, and a part of the outer periphery of the roller bearing 37 a rotatably supported by the inner pin 37 is in contact with a part of the inner periphery of the pin hole 36.

  As shown in FIG. 2, the speed reducer B includes two curved plates 31 as revolving members that are rotatably held by the eccentric shaft portions 30a and 30b, and a corrugated tooth profile 31a on the outer peripheral portion of the curved plate 31 (FIG. 3). A plurality of outer pins 32 that engage with each other, an output shaft 33 that outputs the rotational movement of the curved plate 31, and a curved surface that is attached to the gap between the two curved plates 31 and abuts against the end surfaces of these curved plates 31. And a center collar 38 for preventing the plate from tilting.

  The output shaft 33 has a flange portion 33a and a shaft portion 33b. As shown in FIG. 3, inner pins 37 are fixed to the flange portion 33 a at equal intervals on a circumference centered on the rotation axis of the output shaft 33. A wheel hub C is provided on the outer diameter surface of the shaft portion 33b so that torque can be transmitted by serration (or spline) (see FIG. 1). The flange portion 33a and the stabilizer 33d are connected via the plurality of inner pins 37, and the output shaft 33 and the stabilizer 33d rotate integrally. A pump drive shaft 33c connected to the inner rotor 72 of the oil pump 42 is integrally provided at the end of the stabilizer 33d on the motor part A side.

  The outer pins 32 are provided at equal intervals on the circumferential track of the rotation axis of the input shaft 30. When the curved plate 31 revolves, the outer peripheral corrugated tooth profile 31a and the outer pin 32 engage with each other, causing the curved plate 31 to rotate.

  As shown in FIG. 2, an output shaft 33 and a stabilizer 33 d are rotatably supported via a rolling bearing 90 on the inner circumference of the pair of split plates 50 a and 50 b. Further, the inner diameter surface of the flange portion 33 a and the stabilizer 33 d of the output shaft 33 and the outer diameter surface of the input shaft 30 are supported through a rolling bearing 91 so as to be relatively rotatable.

  The curved plate 31 is incorporated between the flange portion 33a and the stabilizer 33d facing the output shaft 33. Further, both ends of the inner pin 37 penetrating the pin hole 36 of the incorporated curved plate 31 are supported by the opposing flange portion 33a and the stabilizer 33d of the output shaft 33.

  The plurality of inner pins 37 supported by the flange portion 33 a and the stabilizer 33 d that face the output shaft 33 are provided at equal intervals on a circumferential track centering on the rotational axis of the input shaft 30, and friction with the curved plate 31. In order to reduce the resistance, needle roller bearings 37a are provided at positions where they contact the inner wall surfaces of the pin holes 36 of the two curved plates 31. The inner diameter dimension of the pin hole 36 is set to be larger than the outer diameter dimension of the inner pin 37 (referred to as “maximum outer diameter including the needle roller bearing 37a”; the same applies hereinafter).

  As shown in FIG. 6, the reducer B has an input shaft 30, two curved plates 31, a counterweight 35, an output shaft 33, an inner pin 37, with a pair of divided plates 50 a and 50 b opened on both sides. After assembling the internal parts of the speed reducer B such as the rolling bearings 90 and 91, the divided plates 50a and 50b incorporating the outer ring 55a and the needle rollers 55b of the needle roller bearing 55 are then connected to the internal parts of the speed reducer B from the left and right. Then, the outer pin 32 is inserted, and the outer pin side plate 58 is attached to the end surface to complete the assembly.

  Thus, since the internal components of the reduction gear B can be assembled with the pair of split plates 50a and 50b open, the reduction gear B can be easily assembled.

  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 divided plates 50a and 50b, which require high strength, from steel.

  As shown in FIG. 2, the split plates 50a and 50b are provided with a plurality of outer pin holding holes 54 penetrating in the thickness direction. The outer pin holding holes 54 extend in a direction parallel to the rotation axis of the input shaft 30 and hold both ends of the outer pin 32. Both ends of the outer pin 32 are supported by the outer pin holding hole 54 via needle roller bearings 55. The needle roller bearing 55 includes an outer ring 55a and needle rollers 55b having an inner peripheral surface of the outer ring 55a and an outer peripheral surface of the outer pin 32 as rolling surfaces. The outer ring 55 a of the needle roller bearing 55 is fitted into the inner surface of the outer pin holding hole 54.

  Further, the corresponding outer pin holding holes 54 of the pair of divided plates 50a and 50b are provided to face each other at the same position in the circumferential direction. That is, the center axes of the pair of outer pin holding holes 54 coincide with each other, and when the pair of split plates 50a and 50b are attached to the casing 22b of the speed reducer B, the center axis of the outer pin holding holes 54 is the rotation of the input shaft 30. Parallel to the axis. Thereby, the outer pin 32 can be held in parallel with the rotation axis of the input shaft 30.

  As shown in FIG. 2, outer pin side plates 58 that prevent the outer pins 32 inserted into the outer pin holding holes 54 from coming off in the axial direction are fixed to the outer surface portions of the pair of divided plates 50a and 50b, respectively.

  Next, in the embodiment shown in FIGS. 7 and 8, in order to maintain the axial distance between the pair of divided plates 50a and 50b, a stepped distance holding pin 61 is provided between the pair of divided plates 50a and 50b. It is provided and an excessive load is prevented from being applied to the rotating parts arranged between the pair of divided plates 50a and 50b. A pair of divided plates 50a and 50b are formed with fitting holes 62 into which stepped spacing pins 61 are fitted. Between the stepped spacing pins 61 and the fitting holes 62, a pair of divided plates is provided. A gap of about 50 to 500 μm is provided in the radial direction so that the relative movement of 50a and 50b is possible. A plurality of spacing pins 61 are provided at equal intervals in the circumferential direction. In the example of FIG. 8, two spacing pins 61 are provided.

  Next, in the embodiment shown in FIG. 9 and FIG. 10, opposed recesses 62 a and 62 b are provided on the outer diameter surfaces of the pair of split plates 50 a and 50 b and the inner diameter surface of the casing 22 b of the speed reducer B. This is an example in which the relative movement of the pair of split plates 50a and 50b is ensured by inserting the anti-rotation member 63 into the places 62a and 62b with a gap. The clearance between the recesses 62a and 62b and the rotation stopper 63 is about 50 to 500 μm in the radial direction so that relative movement is possible. A plurality of anti-rotation members 63 are provided at equal intervals in the circumferential direction. In the example of FIG. 10, four detent members 63 are provided at intervals of 90 degrees.

Next, the embodiment shown in FIG. 11 and FIG. 12 is provided with a convex portion 64 and a concave portion 65 that fit each other on the outer diameter surfaces of the pair of split plates 50a and 50b and the inner diameter surface of the casing 22b of the speed reducer B. This is an example of stopping. Between this convex part 64 and the recessed part 65, the clearance gap of about 50-500 micrometers is provided in the radial direction, and the relative motion of a pair of division | segmentation plate 50a, 50b is ensured. A plurality of anti-rotation members 63 are provided at equal intervals in the circumferential direction. In the example of FIG. 12, four detent members 63 are provided at intervals of 90 degrees.
In the embodiment of FIGS. 7 to 12, if the radial gap is 50 μm or less, it is difficult to obtain the alignment effect, and if it is 500 μm, the play is too large, causing vibration.

  As shown in FIG. 1, the wheel hub C includes an inner ring member 81 fixedly connected to the outer diameter surface of the shaft portion 33b of the output shaft 33, and an outer ring member 82 that rotatably holds the inner ring member 81 with respect to the casing 22b. With. The inner ring member 81 and the outer ring member 82 constitute a double-row angular ball bearing, and a double-row rolling element 83 is installed between the inner ring member 81 and the outer ring member 82. The inner ring member 81 is integrally provided with a wheel mounting flange portion 84.

  In the above-described embodiment, an example of a cylindrical roller bearing has been shown as the rolling bearing 34 that supports the curved plate 31. However, the present invention is not limited to this example. For example, a plain bearing, a deep groove ball bearing, a tapered roller bearing, and a needle roller Bearings, spherical roller bearings, angular contact ball bearings, 4-point contact ball bearings, etc., whether they are plain bearings or rolling bearings, regardless of whether the rolling elements are rollers or balls, All bearings can be applied, whether double row or single row. Similarly, any type of bearing can be adopted for bearings arranged in other locations.

  Moreover, in the said embodiment, the radial gap provided with the stator 23 fixed to the casing 22a in the motor part A, and the rotor 24 arrange | positioned in the position which faces the inner side of the stator 23 with a radial gap. Although the example which employ | adopted the motor was shown, the motor of arbitrary structures is applicable, without restricting to this. For example, an axial gap motor in which the stator and the rotor are arranged to face each other via a gap opened in the axial direction may be used.

  Furthermore, the electric vehicle equipped with the in-wheel motor drive device 21 according to the present invention may have the rear wheels as drive wheels, the front wheels as drive wheels, or a four-wheel drive vehicle. In the present specification, “electric vehicle” is a concept including all vehicles that obtain driving force from electric power, and should be understood as including, for example, a hybrid vehicle.

11: Electric vehicle 12: Chassis 12a: Wheel housing 12b: Suspension device 13: Front wheel 14: Drive wheel 21: In-wheel motor drive device 22: Casing 22a: Casing 22b: Casing 23: Stator 24: Rotor 24a: Motor shaft 25a: Bearing 25b: Bearing 30: Input shaft 30a: Eccentric shaft portion 30b: Eccentric shaft portion 31: Curved plate 31a: Corrugated tooth profile 32: Outer pin 33: Output shaft 33a: Flange portion 33b: Shaft portion 33c: Pump drive shaft 33d: Stabilizer 34: Rolling bearing 35: Counter weight 36: Pin hole 37: Inner pin 37a: Bearing 38: Center collar 41: Oil tank 42: Oil pump 43: Oil supply passage 44: Internal passage 45: Internal passage 46: Return passage 47: Exhaust Outlet 50a: Dividing plate 50b: Minute Plate 51: Thick part 54: Outer pin holding hole 55: Bearing 55a: Outer ring 55b: Needle roller 58: Outer pin side plate 60: Non-rotating member 61: Spacing holding pin 62: Fitting hole 62a: Recess 62b: Recess 63: Anti-rotation member 64: Convex portion 65: Concavity 72: Inner rotor 72a: Tooth tip portion 72b: Tooth groove portion 73: Outer rotor 73a: Tooth tip portion 73b: Tooth groove portion 74: Pump chamber 75: Inlet 76: Discharge port 77: Pump case 81: Inner ring member 82: Outer ring member 83: Rolling element 84: Wheel mounting flange part 90: Rolling bearing 91: Rolling bearing A: Motor part B: Reducer C: Wheel hub c1: Wheel center c1 c2: Center of rotation

Claims (5)

  A motor unit that generates a driving force, a speed reducer that decelerates and outputs the rotation of the motor unit, and a wheel hub that transmits the output from the speed reducer to a drive wheel, and the speed reducer is rotationally driven by the motor unit. An input shaft, a curved plate that is rotatably supported by the input shaft by an eccentric shaft portion provided on the input shaft, and has a corrugated tooth profile formed on the outer periphery, and an outer pin that meshes with the corrugated tooth profile on the outer periphery of the curved plate, An outer pin holding hole provided on the inner diameter surface of the reducer casing and supporting both ends of the outer pin via a bearing, and the curved plate is moved in an eccentric manner by rotating the input shaft. A pair of in-wheel motor drive devices, which are cycloidal reduction gears configured to output rotation from an output shaft arranged coaxially with the input shaft, and capable of moving relative to each other on an inner diameter surface of a casing of the reduction gear. Split Place a rate, in this division plate, in-wheel motor drive device characterized by the formation of the outer pin holding hole for supporting both ends of the outer pins via bearings.   The in-wheel motor drive device according to claim 1, wherein an anti-rotation member capable of elastic deformation is provided between the pair of divided plates and an inner diameter surface of a casing of the speed reducer.   2. An opposing recess is provided in an outer diameter surface of the pair of divided plates and an inner diameter surface of a casing of the speed reducer, and a detent member is fitted in the recess so as to be capable of relative movement. In-wheel motor drive device.   Protrusions and recesses that fit into each other are provided on the outer diameter surface of the pair of split plates and the inner diameter surface of the casing of the speed reducer, and a gap is provided between the convex portions and the recesses so that the pair of split plates can move relative to each other. The in-wheel motor drive device according to claim 1, wherein the in-wheel motor drive device is fitted with a gap.   The in-wheel motor drive device according to any one of claims 1 to 4, wherein a spacing pin is fitted between the pair of divided plates.

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