JP2016114184A - Cycloid speed reducer and in-wheel motor drive with cycloid speed reducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cycloid speed reducer showing superior acoustic performance and durability life.SOLUTION: This invention relates to a cycloid speed reducer comprising curved plates 26a, 26b rotatably fitted to the outer circumferences of eccentric parts 25a, 25b through a first rolling bearing Rb1; a motion converting mechanism for converting a rotation movement of the curved plates into a rotating motion of an output shaft 28; and a counter weight 29 arranged to be adjacent to an axial outside of the eccentric parts and the motion converting mechanism includes an inner pin 31 inserted into an open hole 30a of the curved plate and a second rolling bearing Rb2 fitted to the opposing part against the inner wall surface of open-hole in the inner pin, there are provided first and second oil supply passages F1, F2 for supplying lubricant oil flowing at an oil passage 25c extending in an input shaft 25 in an axial direction to each of the first and second rolling bearings. The second oil supply passage F2 is constituted by an oil passage 29c opened at both end surfaces of the counterweight and an oil passage 25d1 extending within the input shaft in a radial direction to cause the oil passage to be communicated with an oil passage of the counterweight 29.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cycloid reducer and an in-wheel motor drive device including the same.

As is well known, an in-wheel motor drive device is housed inside the wheel or disposed near the wheel, so that the weight and size of the in-wheel motor drive device are the unsprung weight (running performance) of the vehicle and the cabin space. Affects the size of For this reason, the in-wheel motor drive device needs to be as light and compact as possible. On the other hand, the in-wheel motor drive device requires a large torque to drive the wheels. In order to satisfy these requirements at the same time, for example, in Patent Document 1 below, a motor unit that generates a driving force employs a high-rotation type motor that rotates at a maximum rotational speed of about 15000 min ⁻¹ , and a motor unit. An in-wheel motor drive device has been proposed that employs a cycloid reduction gear that is compact and can provide a high reduction ratio in a reduction gear portion that should be provided between a wheel bearing portion that connects and fixes a wheel.

  The cycloid speed reducer disclosed in Patent Document 1 mainly fits rotatably on the outer periphery of the eccentric part via an input shaft having an eccentric part and a rolling bearing (hereinafter also referred to as “curved plate support bearing”). A curved plate that performs a revolving motion around its rotational axis as the input shaft rotates, and an outer pin that engages with the outer periphery of the curved plate during the revolving motion to cause the curved plate to rotate. A motion conversion mechanism that converts the rotational movement of the curved plate to the rotational movement of the output shaft, and an axially outer side of the eccentric part, to cancel the unbalanced inertia couple generated by the rotation of the curved plate (eccentric rotation) Counter weight.

  The motion conversion mechanism mainly includes an axial through hole opened on both end faces of the curved plate, and an inner pin inserted into the through hole with one end fixed to the output shaft. A rolling bearing (hereinafter also referred to as “inner pin bearing”) is fitted to a portion of the through hole facing the inner wall surface. If such an inner pin bearing is provided, the frictional resistance (contact resistance) between the inner pin and the curved plate is reduced, so that torque loss in the motion conversion mechanism is suppressed.

  Moreover, the cycloid reduction gear of patent document 1 has a lubrication mechanism for supplying lubricating oil to each part, and this lubrication mechanism includes an axial oil passage that extends in the axial direction inside the input shaft, and an input shaft. And a radial oil passage that extends in the radial direction and discharges lubricating oil flowing in the axial oil passage to the outer diameter side of the input shaft. The radial oil passage constitutes a part of an oil supply passage for supplying lubricating oil to the raceway surface of the curved plate support bearing. For example, as shown in FIG. 13 and FIG. There is a case where it is provided within the axial range of the part, or a case where it is provided at the boundary between the eccentric part and the counterweight as shown in FIG.

JP 2012-141028 A

  By the way, in order to realize a cycloid reducer with excellent acoustic performance (silence) and durability life, in addition to the curved plate support bearing, for example, an inner pin bearing (inside), an inner pin bearing and a curved plate It is desired that a sufficient amount of lubricating oil can be supplied to the contact portion, the contact portion between the curved plate and the outer pin, and the like. In particular, the inner pin bearing, like the curved plate support bearing, is repeatedly subjected to a load that varies in size and direction as the curved plate rotates, so a sufficient amount of lubricating oil is applied to the inner pin bearing. It is preferable to supply. However, in the cycloid reduction gear of Patent Document 1, the lubricating oil is supplied to the inner pin bearing or the like using a centrifugal force acting on the lubricating oil discharged from the radial oil passage of the input shaft. In this case, the lubricating oil discharged from the radial oil passage of the input shaft is considered to diffuse widely in each part of the reducer, and it is not always possible to supply a sufficient amount of lubricating oil to the inner pin bearing. Absent.

  On the other hand, as described above, the cycloid reducer is used, for example, as a reduction unit of an in-wheel motor drive device, and therefore can be manufactured as inexpensively as possible in order to reduce the cost of the in-wheel motor drive device. desired.

  In view of the above circumstances, the problem to be solved by the present invention is to reliably supply a sufficient amount of lubricating oil not only to the curved plate support bearing but also to the inner pin bearing while avoiding an increase in cost as much as possible. It is an object of the present invention to provide a cycloid reducer that can be obtained, and to provide a cycloid reducer that is relatively low in cost and excellent in acoustic performance, durability life, and the like, and thus an in-wheel motor drive device equipped with the cycloid reducer.

  The present invention, which has been devised to solve the above-mentioned problems, is fitted with an input shaft having an eccentric portion, and is rotatably fitted to the outer periphery of the eccentric portion via a first rolling bearing. A curved plate that performs a revolving motion around the rotation axis, an outer pin that engages with the outer periphery of the curved plate to cause the curved plate to rotate, and converts the rotational motion of the curved plate into a rotational motion of the output shaft. A through hole in which the motion conversion mechanism is disposed adjacent to the outer side in the axial direction of the eccentric portion and has a counterweight that counteracts the unbalanced inertia couple generated by the rotation of the curved plate. And a cycloid reducer including an inner pin inserted into the through hole with one end fixed to the output shaft, and a second rolling bearing fitted to a portion of the inner pin facing the inner wall surface of the through hole. Axial oil extending in the axial direction inside the input shaft Through-holes having first and second oil supply passages for supplying lubricating oil flowing through the first and second rolling bearings to each end face of the counterweight And a radial oil passage that extends radially inside the input shaft and communicates the axial oil passage with the oil passage of the counterweight. Each of the “first rolling bearing” and the “second rolling bearing” in the present invention corresponds to the “curved plate support bearing” and the “inner pin bearing” described above.

  As described above, the first and second lubricant oils flowing through the axial oil passage of the input shaft are supplied to the first rolling bearing (curved plate support bearing) and the second rolling bearing (inner pin bearing), respectively. If the oil supply passage is provided, the lubricating oil flowing in the axial oil passage of the input shaft can be directly supplied not only to the first rolling bearing but also to the second rolling bearing. In particular, in the present invention, the counterweight disposed adjacent to the outer side in the axial direction of the eccentric portion is provided with through holes that are opened on both end surfaces, and this through hole is utilized as a second oil supply passage (part of the above). Depending on how the through holes are formed, part of the lubricating oil flowing through the second oil supply passage can be supplied to the first rolling bearing. Furthermore, the counterweight having the through-holes opened at both end faces can be obtained by an inexpensive manufacturing method such as a method of punching a metal plate (pressing) or a method of compressing and then sintering raw material powder. it can. Therefore, it is possible to realize a cycloid reducer that can reliably supply a sufficient amount of lubricating oil to both the first and second rolling bearings while avoiding an increase in cost as much as possible.

  The cycloid reduction gear can be provided with a stabilizer having a flange portion to which the other end of the inner pin is fixed and a cylindrical portion fitted to the outer periphery of the input shaft via a third rolling bearing. In this case, the second oil supply passage can be configured to include a through hole (a through hole in the radial direction) opened in the inner diameter surface and the outer diameter surface of the cylindrical portion of the stabilizer.

  If the third rolling bearing that supports the stabilizer so as to be rotatable with respect to the input shaft is disposed adjacent to the outer side of the counterweight in the axial direction, a part of the lubricating oil flowing through the second oil supply passage is transferred to the third rolling bearing. It becomes possible to efficiently supply the bearing.

  The inner pin can be provided with an internal oil passage that opens to the other end surface and the mating surface of the second rolling bearing. In this case, the second oil supply passage further includes the above-described internal oil passage. Can be configured. At this time, if a guide member for guiding the lubricant discharged from the outer diameter side opening of the through hole of the stabilizer to the other end surface side of the inner pin is arranged on the outer diameter side of the cylindrical portion of the stabilizer, Since the lubricating oil easily flows into the internal oil passage of the pin bearing, the lubricating oil can be efficiently supplied to the second rolling bearing as the inner pin bearing.

  The cycloid speed reducer according to the present invention described above can be preferably applied to, for example, a speed reduction part of an in-wheel motor drive device having a motor part, a speed reduction part, and a wheel bearing part. In this case, if the input shaft of the cycloid reducer is connected to the rotating shaft of the motor unit so as to be able to transmit torque, an in-wheel motor drive device having excellent acoustic performance and durability can be realized.

  As described above, according to the present invention, a sufficient amount of lubricating oil is provided for both the first rolling bearing as the curved plate support bearing and the second rolling bearing as the inner pin bearing while avoiding the cost increase as much as possible. It is possible to realize a cycloid reducer that can reliably supply Thereby, it is possible to provide a cycloid reduction gear that is relatively low cost and excellent in acoustic performance, durability life, and the like, and thus an in-wheel motor drive device equipped with the same.

It is a figure which shows an example of the in-wheel motor drive device which applied the cycloid reduction gear which concerns on one Embodiment of this invention to the deceleration part. It is a principal part enlarged view of FIG. 1, Comprising: It is an enlarged view of a deceleration part. (A) The figure shows the fitting aspect of the counterweight of the inboard side with respect to the input shaft of a deceleration part, (b) The figure and (c) figure are the fitting aspects of the counterweight of the inboard side with respect to the input shaft. FIG. FIG. 2 is a cross-sectional view taken along line X1-X1 in FIG. It is explanatory drawing which shows the load which acts on the curve board which comprises a deceleration part. It is a cross-sectional view of a rotary pump. It is a schematic plan view of the electric vehicle carrying an in-wheel motor drive device. It is the schematic sectional drawing which looked at the electric vehicle of Drawing 7 from back.

  First, an outline of the electric vehicle 11 equipped with the in-wheel motor drive device will be described with reference to FIGS. As shown in FIG. 7, the electric vehicle 11 includes an chassis that drives each of a chassis 12, a pair of front wheels 13 that function as steering wheels, a pair of rear wheels 14 that function as drive wheels, and left and right rear wheels 14. A wheel motor drive device 21. As shown in FIG. 8, the rear 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 the suspension device 12b.

  The suspension device 12b supports the rear 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 rear wheel 14 from the road surface by a strut including a coil spring and a shock absorber. Furthermore, a stabilizer that suppresses the inclination of the vehicle body during 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 rear wheel 14 to the road surface. desirable.

  In this electric vehicle 11, an in-wheel motor drive device 21 that rotates each of the left and right rear wheels 14 is incorporated in the left and right wheel housings 12 a, so that a motor, a drive shaft, a differential gear mechanism, and the like are mounted on the chassis 12. There is no need to provide it. Therefore, the electric vehicle 11 has an advantage that a large cabin space can be secured and the rotation of the left and right rear wheels 14 can be controlled.

  In order to improve the running stability and NVH characteristics of the electric vehicle 11, it is necessary to suppress the unsprung weight. Moreover, in order to expand the cabin space of the electric vehicle 11, it is necessary to reduce the size of the in-wheel motor drive device 21. Therefore, an in-wheel motor drive device 21 as shown in FIG. 1 is employed.

  An example of an in-wheel motor drive device 21 in which a cycloid reduction gear according to an embodiment of the present invention is applied to a speed reduction unit will be described with reference to FIGS. As shown in FIG. 1, the in-wheel motor drive device 21 includes a motor unit A that generates a driving force, a deceleration unit B that decelerates and outputs the rotation of the motor unit A, and outputs the deceleration unit B to the rear wheel 14. (Refer to FIGS. 7 and 8) and a wheel bearing portion C for transmission to the casing 22, which are held by the casing 22. The casing 22 is mounted in the wheel housing 12a (see FIG. 8) of the electric vehicle 11.

The motor portion A includes a stator 23a fixed to the casing 22, a rotor 23b disposed opposite to the inside of the stator 23a via a radial gap, and a hollow motor rotating shaft 24 having a rotor 23b mounted on the outer periphery. Is a radial gap motor. The motor rotation shaft 24 rotates at a maximum rotation speed of about 15000 min ⁻¹ .

  The motor rotating shaft 24 has ends on one side in the axial direction (right side in FIG. 1, hereinafter also referred to as “inboard side”) and the other side (left side in FIG. 1 and hereinafter also referred to as “outboard side”). A pair of rolling bearings 36, 36 respectively disposed in the part are rotatably supported with respect to the casing 22.

  The wheel bearing portion C includes a hollow hub wheel 32 having a hollow structure and a wheel bearing 33 that rotatably supports the hub wheel 32 with respect to the casing 22. The hub wheel 32 includes a cylindrical hollow portion 32a connected to the shaft portion 28b of the output shaft 28 constituting the speed reduction portion B, and a flange portion extending radially outward from the end portion on the outboard side of the hollow portion 32a. 32b integrally. Since the rear wheel 14 (see FIGS. 7 and 8) is connected and fixed to the flange portion 32b by the bolt 32c, the rear wheel 14 rotates integrally with the hub wheel 32 when the hub wheel 32 rotates.

  The wheel bearing 33 is fitted to an inner member having an inner raceway surface 33 f formed on the outer diameter surface of the hub wheel 32 and an inner ring 33 a fitted to a small diameter step portion of the outer diameter surface, and an inner diameter surface of the casing 22. The outer ring 33b that is fixed together, a plurality of balls 33c disposed between the inner member and the outer ring 33b, a cage 33d that holds the balls 33c in a circumferentially spaced state, and the axial direction of the wheel bearing 33 It is a double row angular contact ball bearing provided with a pair of seal members 33e, 33e for sealing both ends.

  The speed reduction unit B includes an input shaft 25 that is rotationally driven by the motor unit A, an output shaft 28 that is arranged coaxially with the input shaft 25, and a speed reduction that transmits the speed to the output shaft 28 after reducing the rotation of the input shaft 25. The cycloid reduction gear provided with the mechanism is employ | adopted. The output shaft 28 transmits the rotation of the input shaft 25 decelerated by the deceleration mechanism to the wheel bearing portion C.

  The input shaft 25 fits a spline 25g (including serrations; the same applies hereinafter) formed on the outer periphery of the end portion on the inboard side to a spline formed on the inner periphery of the end portion on the outboard side of the motor rotation shaft 24. The motor rotating shaft 24 is connected so as to be able to transmit torque by so-called spline fitting.

  As shown in FIG. 2 in an enlarged manner, at two locations in the axial direction of the input shaft 25, eccentric portions 25a and 25b whose shaft centers are eccentric with respect to the rotational axis of the input shaft 25 are integrated or separated (this embodiment). It is provided integrally). The two eccentric portions 25a and 25b are provided with a phase difference of 180 ° in order to cancel out the centrifugal force generated by the eccentric motion (eccentric rotation).

  The input shaft 25 is rotatably supported with respect to the output side of the speed reduction unit B by rolling bearings 37A and 37B that are spaced apart from each other in two axial directions. More specifically, the input shaft 25 is rotatable with respect to a stabilizer 70 and an output shaft 28, which will be described later, by rolling bearings 37A and 37B disposed at the substantially central portion in the axial direction and the end portion on the outboard side, respectively. It is supported. Accordingly, the rolling bearing 37A corresponds to the third rolling bearing Rb3 referred to in the present invention. The rolling bearings 37A and 37B are ball bearings using balls as rolling elements.

  As shown in FIG. 1, the output shaft 28 includes a shaft portion 28b and a flange portion 28a. The flange portion 28 a has a hole portion (through hole in the illustrated example) to which an end portion on the outboard side of the inner pin 31 to be described later is fixed, and the hole portion has a circumference centering on the rotation axis of the output shaft 28. A plurality are formed at equal intervals on the top. The shaft portion 28b is connected to the hub wheel 32 of the wheel bearing portion C by spline fitting. The output shaft 28 is rotatably supported by the outer pin housing 60 via the outboard-side rolling bearing 48 among the pair of rolling bearings 48, 48 disposed on both axial sides of the inner pin 31.

  As shown in FIG. 2, the speed reduction mechanism includes curved plates 26a and 26b that are rotatably fitted on the outer circumferences of the eccentric portions 25a and 25b via rolling bearings 40 and 40 as the first rolling bearing Rb1, and curved lines. A plurality of outer pins 27 engaged with the outer peripheral portions of the plates 26a and 26b, a motion conversion mechanism for converting the rotational motion of the curved plates 26a and 26b into the rotational motion of the output shaft 28, and the axially outer sides of the eccentric portions 25a and 25b And a pair of counterweights 29 and 29 arranged adjacent to each other.

  As shown in FIG. 4, the curved plate 26a has a plurality of waveforms formed on its outer peripheral portion by a trochoidal system curve such as epitrochoid. The curved plate 26a has axial through-holes 30a and 30b that open at both end faces thereof. A plurality of through holes 30a are provided at equal intervals on the circumference centered on the rotation axis of the curved plate 26a, and one inner pin 31 described later is inserted into each through hole 30a. The through hole 30 b is provided at the center of the curved plate 26 a and is fitted to the outer periphery of the eccentric portion 25 a via the rolling bearing 40.

  As shown in FIGS. 2 and 4, the rolling bearing 40 includes an inner ring 41 having an inner raceway surface 42 on an outer diameter surface, an outer raceway surface 43 formed directly on the inner wall surface of the through hole 30b of the curved plate 26a, The cylindrical roller bearing includes a plurality of cylindrical rollers 44 disposed between the inner raceway surface 42 and the outer raceway surface 43, and a retainer 45 that holds the cylindrical rollers 44. The inner ring 41 has flanges 46 that protrude radially outward from both axial ends of the inner raceway surface 42. In the rolling bearing 40 of the present embodiment, the inner raceway surface 42 is formed on the inner ring 41 provided separately from the eccentric portion 25a. However, by forming the inner raceway surface directly on the outer diameter surface of the eccentric portion 25a. The inner ring 41 may be omitted. In this case, the speed reduction part B can be reduced in weight and size.

  Although a detailed description is omitted, the curved plate 26b has a structure similar to that of the curved plate 26a, and with respect to the eccentric portion 25b via the rolling bearing 40 similar to the rolling bearing 40 that supports the curved plate 26a. It is supported rotatably.

  As shown in FIG. 4, a plurality of outer pins 27 are provided at equal intervals on a circumference centered on the rotation axis of the input shaft 25. When the curved plates 26a and 26b revolve as the input shaft 25 rotates, the outer pin 27 engages with the outer peripheral portions of the curved plates 26a and 26b, causing the curved plates 26a and 26b to rotate. As shown in FIG. 2, each outer pin 27 includes a pair of rolling bearings (needle roller bearings) 61 and 61 arranged at both ends in the axial direction, and an outer pin housing that holds the needle roller bearings 61 and 61. It is rotatably supported by the casing 22 via 60. With this configuration, the contact resistance between the outer pin 27 and the curved plates 26a and 26b is reduced.

  Although not shown in detail, the outer pin housing 60 is supported in a floating state with respect to the casing 22 by a detent means (not shown) having an elastic support function. This is a component of a motion conversion mechanism that absorbs a large radial load or moment load caused by turning or sudden acceleration / deceleration of the vehicle and converts the rotational motion of the curved plates 26a, 26b into the rotational motion of the reducer output shaft 28. This is to prevent damage.

  The counterweight 29 has a substantially fan shape as a whole, and is fitted and fixed to the outer periphery of the input shaft 25. Each counterweight 29 is arranged with a 180 ° phase shift from the eccentric portion 25a (or 25b) adjacent in the axial direction in order to cancel out the unbalanced inertia couple generated by the rotation of the curved plates 26a, 26b. Note that when the counterweight 29 and the input shaft 25 rotate relative to each other, the counterweighting inertia couple canceling function is adversely affected. Therefore, the counterweight 29 is fixed to the input shaft 25 in a non-rotating state. In the present embodiment, as shown in FIG. 3A, the shaft parallel plane (D cut portion) 25 f formed in the fitting area of the counterweight 29 in the outer diameter surface of the input shaft 25, and the counterweight 29 By fitting the counterweight 29 to the input shaft 25 with the phase of the axis parallel plane corresponding to the axis parallel plane 25f formed on the inner diameter surface being matched, the relative rotation of the counter weight 29 and the input shaft 25 is restricted. .

  Here, with reference to FIG. 2 and FIG. 3A, the counterweight 29 arranged adjacent to the axially outer side (inboard side) of the eccentric portion 25a will be described in detail. The counterweight 29 integrally includes a substantially fan-shaped weight portion 29a and an annular base portion 29b. The end surface on the outboard side contacts the eccentric portion 25a and the end surface on the inboard side is a rolling bearing 37A. Are fitted and fixed to the outer periphery of the input shaft 25. The base portion 29b is thicker than the weight portion 29a so that the end surface on the inboard side of the weight portion 29a faces the end surface on the outboard side of the rolling bearing 37A and the stabilizer 70 with an axial gap 73 therebetween. So as to protrude toward the board side). Further, the counterweight 29 has an oil passage 29c constituting a second oil supply passage F2 in a lubrication mechanism described later. The oil passage 29c is an axial through-hole opened at both end faces of the counterweight 29. Consists of. In the present embodiment, the outermost diameter portion of the oil passage 29 c (through hole) is located on the radially outer side than the outer diameter surface of the flange portion 46 of the rolling bearing 40. However, as long as oil can flow from the rolling bearing 37A side, the outermost diameter portion of the oil passage 29c does not need to be positioned on the radially outer side of the outer diameter surface of the flange portion 46.

  Note that the counterweight 29 arranged adjacent to the outer side in the axial direction (outboard side) of the eccentric part 25b has the same configuration as the counterweight 29 arranged adjacent to the outer side of the eccentric part 25a in the axial direction. In short, the two counterweights 29 and 29 are the same parts having the same structure.

  As shown in FIGS. 2 and 4, the motion conversion mechanism includes a plurality of through holes 30a provided in the curved plates 26a and 26b, a plurality of inner pins 31 inserted into each through hole 30a, and an inner pin. 31 includes a needle roller bearing 72 serving as a second rolling bearing Rb2 fitted in a portion facing the inner wall surface of the through hole 30a. The inner pins 31 are arranged at equal intervals on the circumference centered on the rotational axis of the output shaft 28, and the end 31 a on the outboard side is in a hole provided in the flange portion 28 a of the output shaft 28. The fitting is fixed. The inner diameter dimension of the through hole 30a is set larger than the outer diameter dimension of the inner pin 31 (referred to as “maximum outer diameter including the needle roller bearing 72”; the same applies hereinafter). By providing the needle roller bearing 72 in this manner, the frictional resistance between the inner pin 31 and the curved plates 26a and 26b is reduced, and torque loss in the motion change mechanism is prevented as much as possible.

  As shown in FIG. 2, the speed reduction unit B further includes a stabilizer 70. The stabilizer 70 integrally includes a flange portion 70a and a cylindrical portion 70b extending from the inner diameter portion of the flange portion 70a toward the inboard side, and an end portion 31b on the inboard side of each inner pin 31 is formed on the flange portion 70a. It fits and is fixed to the through-hole opened on both end surfaces. By providing such a stabilizer 70, the load applied to some of the inner pins 31 from the curved plates 26 a and 26 b when the motor unit A is driven (when the input shaft 25 rotates) is applied to the output shaft 28 and the stabilizer 70. Are supported by all the inner pins 31.

  Here, the state of the load acting on the curved plate 26a and further on the input shaft 25 when the motor part A is driven will be described with reference to FIG. When the motor unit A is driven, a load acts on the curved plate 26b in the same manner as described below.

The axis O ₂ of the eccentric portion 25 a provided on the input shaft 25 is eccentric from the axis (rotation axis) O of the input shaft 25 by the amount of eccentricity e. Eccentric portion 25a, so that rotatably supports the curve plate 26a via a rolling bearing 40, the axis O ₂ is also the axis of the curved plate 26a. The outer peripheral portion of the curved plate 26a is formed by a waveform curve, and has concave portions 34 that are recessed inward in the radial direction at equal intervals in the circumferential direction. Around the curved plate 26 a, a plurality of outer pins 27 that are engaged with the recesses 34 in the circumferential direction are arranged in the circumferential direction around the axis O of the input shaft 25.

  In FIG. 5, when the input shaft 25 rotates counterclockwise on the paper surface, the eccentric portion 25 a and the curved plate 26 a fitted to the outer periphery thereof perform a revolving motion around the axis O of the input shaft 25. The concave portion 34 of the curved plate 26a sequentially contacts the outer pin 27 in the circumferential direction. As a result, the curved plate 26a rotates clockwise in response to a load Fi as indicated by an arrow in the drawing from the plurality of outer pins 27.

Further, the curve plates 26a and a plurality of circumferentially disposed around the the axis O ₂ through hole 30a, the through holes 30a, fixed to the input shaft 25 coaxially disposed output shaft 28 An internally provided pin 31 is inserted. Since the inner diameter of the through hole 30a is larger than the outer diameter of the inner pin 31, the inner pin 31 does not hinder the revolving motion of the curved plate 26a, and the inner diameter of the through hole 30a of the rotating curved plate 26a is not reduced. The rotating motion of the curved plate 26a is taken out by contacting the wall surface, and the output shaft 28 is rotated (converted into the rotational motion of the output shaft 28). At this time, the output shaft 28 has a higher torque and a lower rotational speed than the input shaft 25, and the curved plate 26a receives a load Fj as indicated by arrows in the figure from the plurality of inner pins 31. The resultant force Fs of these loads Fi and Fj acts on the input shaft 25 via the rolling bearing 40.

The direction of the resultant force Fs changes due to the influence of centrifugal force in addition to geometric conditions such as the shape of the outer peripheral portion of the curved plate 26a and the number of recesses 34. Specifically, through the rotation axis O _2, and the reference line X extending in the direction of 90 ° to the straight line Y connecting the the axis O rotation axis O _2, the angle α formed by the force Fs substantially Fluctuates between 30 ° and 60 °. The directions and magnitudes of the loads Fi and Fj change during one rotation of the input shaft 25. As a result, the resultant force Fs acting on the input shaft 25 also varies in the direction and magnitude of the load. . Then, when the input shaft 25 rotates once, the concave portion 34 of the curved plate 26a is decelerated and rotated clockwise by one pitch, resulting in the state shown in FIG.

  The in-wheel motor drive device 21 has a lubrication mechanism that supplies lubricating oil to various portions of the motor part A and the speed reduction part B mainly in a flow as shown by white arrows in FIGS. This lubrication mechanism includes an oil passage 22a provided in the wall portion of the casing 22, oil passages 24a and 24b provided in the motor rotation shaft 24, oil passages 25c, 25d1 to 25d3 and 25e provided in the input shaft 25 (inboard side). The oil passage 29c provided in the counterweight 29, the oil passage 70c provided in the stabilizer 70, the internal oil passage 31e provided in the inner pin 31, the oil discharge port 22b provided in the casing 22, and the casing 22 are provided below. The lubricating oil storage part 22d which stores lubricating oil (temporarily), the rotary pump 51, and the oil path 22e provided between the lubricating oil storage part 22d and the rotary pump 51, etc. are comprised.

  Note that the in-wheel motor drive device 21 of the present embodiment has a characteristic configuration in a portion of the lubrication mechanism that supplies lubricating oil to various parts of the speed reduction unit B. Specifically, the incline portions 25a and 25b. Each of the rolling bearings 40, 40 (first rolling bearing Rb 1) fitted on the outer periphery of the roller has a first oil supply path F 1 for supplying lubricating oil directly, and has a needle shape fitted to the inner pin 31. Each of the roller bearings 72, 72 (second rolling bearing Rb2) has a second oil supply path F2 for directly supplying the lubricating oil.

  The oil passages 24a and 24b provided in the motor rotating shaft 24 extend in the axial direction and the radial direction inside the motor rotating shaft 24, respectively, and the oil passage 24a extends in the axial direction inside the input shaft 25. An oil passage 25c as an axial oil passage is connected. The oil passages 25d1 to 25d3 constitute radial oil passages extending in the radial direction from the oil passage 25c toward the outer diameter surface of the input shaft 25, and the outer diameter end portions of the oil passages 25d1 to 25d3 are respectively Openings are made in the fitted area of the counterweight 29 on the inboard side, the outer diameter surface of the eccentric portion 25a, and the outer diameter surface of the eccentric portion 25b. The oil passage 25e extends in the axial direction from the end portion on the outboard side of the oil passage 25c, and opens to the outer end surface of the input shaft 25 on the outboard side.

  As shown in FIG. 2, the inner ring 41 of the rolling bearing 40 fitted to the inboard side eccentric portion 25a has a through-hole 41a that opens to its inner diameter surface and outer diameter surface (inner raceway surface 42). The inner ring 41 is fitted to the outer periphery of the eccentric portion 25a so as to match the phase of the through hole 41a and the oil passage 25d2 of the input shaft 25. With this configuration, the oil passage 25c of the input shaft 25 and the internal space of the rolling bearing 40 fitted to the eccentric portion 25a communicate with each other via the oil passage 25d2 of the input shaft 25 and the through hole 41a of the rolling bearing 40. A first oil supply path F1 is formed that can supply the lubricating oil flowing through the oil path 25c of the input shaft 25 to the rolling bearing 40 fitted to the eccentric portion 25a.

  The inner ring 41 of the rolling bearing 40 fitted to the eccentric part 25b on the outboard side also has a through hole 41a that opens to the inner diameter surface and the outer diameter surface. The inner ring 41 is connected to the through hole 41a. The input shaft 25 is fitted to the outer periphery of the eccentric portion 25b so as to be in phase with the oil passage 25d3. With this configuration, the oil passage 25c of the input shaft 25 and the internal space of the rolling bearing 40 fitted to the eccentric portion 25b communicate with each other via the oil passage 25d3 of the input shaft 25 and the through hole 41a of the rolling bearing 40. A first oil supply path F1 is formed which can supply the lubricating oil flowing through the oil path 25c of the input shaft 25 to the internal space of the rolling bearing 40 fitted to the eccentric portion 25b.

  In addition, although illustration is abbreviate | omitted, you may provide an annular groove in the axial direction position in which the oil path (radial oil path) 25d2 is provided among the outer diameter surfaces of the eccentric part 25a, for example. In this case, since the oil passage 25d2 and the through hole 41a of the inner ring 41 can be communicated with each other via the annular groove, when the inner ring 41 is fitted to the outer periphery of the eccentric portion 25a, the oil passage 25d2 and the through hole 41a Phase alignment is not necessary. The same applies to the eccentric portion 25b.

  The oil passage 29c provided in the counterweight 29 on the inboard side is constituted by an axial through-hole opened at both end faces of the counterweight 29, and is arranged to match the number and phase of the oil passage 25d1 provided in the input shaft 25. Is done. In this embodiment, as shown in FIG. 3A, the input shaft 25 is provided with one oil passage 25d1 so that the outer diameter end portion opens to an axis parallel plane (D cut portion) 25f. However, it is not limited to this. That is, the oil passages 25d1 and 29c may be provided in a region whose phase differs from that of the axis parallel plane 25f by about 180 °, for example, as shown in FIG. In addition, the oil passages 25d1 and 29c may be provided not only at one place in the circumferential direction but also at a plurality of places (two places in the illustrated example) in the circumferential direction as shown in FIG.

  As shown in FIG. 2, the oil passage 70 c provided in the stabilizer 70 is configured by a radial through hole opened in the inner diameter surface and the outer diameter surface of the cylindrical portion 70 b of the stabilizer 70. The oil passage 70c of the present embodiment opens at an end surface facing the counterweight 29 on the inboard side, and at least a part of the outer diameter side opening portion is more axial than the end surface 31c on the inboard side of the inner pin 31. The hole diameter, the formation position in the axial direction, and the like are adjusted so as to be located on the outer side in the direction.

  The internal oil passage 31e provided inside the inner pin 31 opens to the end surface 31c on the inboard side of the inner pin 31 and the fitted region 31d of the needle roller bearing 72 on the outer diameter surface of the inner pin 31. Thus, the oil passage extending in the axial direction and the oil passage extending in the radial direction are combined. On the axially outer side of the end surface 31c on the inboard side of the inner pin 31, lubricating oil discharged from the outer diameter end portion of the oil passage 70c of the stabilizer 70 is the end surface 31c of the inner pin 31 (inlet of the inner oil passage 31e). A guiding member 71 for guiding to is disposed.

  With the above configuration, the oil passage 25c extending in the axial direction inside the input shaft 25 and the needle roller bearing 72 (internal space) fitted to the outer periphery of the inner pin 31 are connected to the oil passage 25d1 of the input shaft 25. The oil passage 29c of the counterweight 29 on the inboard side, the gap 73 formed on the end surface of the counterweight 29 on the inboard side, the oil passage 70c of the stabilizer 70, and the internal oil passage 31e of the inner pin 31 communicate with each other. . Thereby, the 2nd oil supply path F2 which can supply the lubricating oil which distribute | circulates the oil path 25c of the input shaft 25 to the needle roller bearing 72 fitted to the inner pin 31 is formed.

  As shown in FIG. 1, the oil discharge port 22 b provided in the casing 22 is for discharging the lubricating oil inside the speed reduction part B to the lubricating oil storage part 22 d, and is a part in which the speed reduction part B is accommodated in the casing 22. Are provided at least at one location. The oil discharge port 22b and the oil passage 24a of the motor rotating shaft 24 are connected via a lubricating oil reservoir 22d, an oil passage 22e, and an oil passage 22a. Therefore, the lubricating oil discharged from the oil discharge port 22b toward the lubricating oil reservoir 22d and stored in the lubricating oil reservoir 22d passes through the oil passage 22e, the oil passage 22a, etc., and the oil passage of the motor rotating shaft 24. It flows into 24a.

The rotary pump 51 is provided between the oil passage 22e and the oil passage 22a connected to the lubricating oil reservoir 22d. By disposing the rotary pump 51 in the casing 22, it is possible to prevent the in-wheel motor drive device 21 from being enlarged as a whole. As shown in FIG. 6, the rotary pump 51 of the present embodiment includes an inner rotor 52 that rotates using the rotation of the output shaft 28, an outer rotor 53 that rotates following the rotation of the inner rotor 52, and both rotors The cycloid pump includes a plurality of pump chambers 54 provided in a space between 52 and 53, a suction port 55 communicating with the oil passage 22e, and a discharge port 56 communicating with the oil passage 22a of the casing 22. The inner rotor 52 rotates around the rotation center c ₁ , and the outer rotor 53 rotates around a rotation center c ₂ different from the rotation center c ₁ of the inner rotor 52. Thus, since the inner rotor 52 and the outer rotor 53 rotate about different rotation centers c ₁ and c ₂ , the volume of the pump chamber 54 changes continuously. As a result, the lubricating oil flowing into the pump chamber 54 from the suction port 55 is pumped from the discharge port 56 to the oil passage 22a.

  The lubrication mechanism having the above configuration lubricates and cools each part of the motor part A and the speed reduction part B as follows.

  First, as shown in FIG. 1, the lubrication of the rotor 23 b and the stator 23 a in the motor part A is mainly performed by the lubricating oil flowing into the oil passage 24 a of the motor rotating shaft 24 through the oil passage 22 a of the casing 22. A part is performed by being discharged from the outer diameter side opening of the oil passage 24 b under the influence of the centrifugal force generated with the rotation of the motor rotating shaft 24 and the pressure of the rotary pump 51. That is, the lubricating oil discharged from the outer diameter side opening of the oil passage 24b is supplied to the rotor 23b and then supplied to the stator 23a. In addition, the rolling bearing 36 that supports the end portion of the motor rotating shaft 24 on the inboard side mainly has a part of the lubricating oil flowing through the oil passage 22 a oozes out between the casing 22 and the motor rotating shaft 24. Lubricated. Further, the rolling bearing 36 that supports the end portion of the motor rotating shaft 24 on the outboard side is mainly discharged from the oil passage 24b, and the inner wall surface of the casing 22 in which the motor portion A is accommodated is disposed. It is lubricated by the lubricant that has passed down.

  Next, as shown in FIG. 2, the lubricating oil flowing through the oil passage 25c of the input shaft 25 via the oil passage 24a of the motor rotation shaft 24 is subjected to centrifugal force accompanying the rotation of the input shaft 25 and the rotation pump 51. By being affected by the pressure, the oil passage 25d1 constituting the second oil supply passage F2, the oil passages 25d2 and 25d3 constituting the first oil supply passage F1, F1, and further the oil passage 25e, Supplied (discharged) inside.

  Specifically, first, the lubricating oil discharged from the outer diameter end portions of the oil passages 25d2 and 25d3 is supplied to the internal space of the rolling bearing 40 through the through holes 41a provided in the inner ring 41 of each rolling bearing 40. Then, the raceway surfaces 42 and 43 and the cylindrical roller 44 are lubricated. Lubricating oil that has lubricated the raceway surfaces 42, 43, etc. is caused by centrifugal force to contact the curved plates 26a, 26b and the inner pins 31 (needle roller bearings 72), or the curved plates 26a, 26b and the outer pins. It moves to the outer side in the radial direction while lubricating the abutting portion and the like. The lubricating oil discharged to the outside of the input shaft 25 through the oil passage 25e lubricates the rolling bearing 37B that supports the end of the input shaft 25 on the outboard side by the action of centrifugal force, and then the rolling bearing. 40 (especially the rolling bearing 40 fitted to the eccentric portion 25b), the abutting portions between the curved plates 26a, 26b and the inner pin 31, and the like are moved radially outward.

  On the other hand, the lubricating oil discharged from the outer diameter end portion of the oil passage 25d1 is an oil passage 29c of the counterweight 29, an axial gap 73, an oil passage 70c of the stabilizer 70, which are disposed adjacent to the outer side in the axial direction of the eccentric portion 25a. The needle roller bearing 72 is supplied via the internal oil passage 31e of the inner pin 31 to lubricate the raceway surface and the needle roller of the needle roller bearing 72. The lubricating oil that has lubricated the inside of the needle roller bearing 72 in this way is similar to the lubricating oil supplied to the rolling bearing 40 via the first oil supply path F1, and the curved plates 26a and 26b, the inner pin 31, And the abutting portions between the curved plates 26a and 26b and the outer pin 27 are moved radially outward while being lubricated. The lubricating oil discharged from the outer diameter end portion of the oil passage 25d1 is a rolling bearing 37A (third rolling bearing Rb3) or an eccentric portion 25a that supports a substantially central portion in the axial direction of the input shaft 25 via the oil passage 29c. Is also supplied to the rolling bearing 40 (first rolling bearing Rb1) fitted to the outer periphery of the bearings, and the raceway surfaces and the like of the rolling bearings 37A and 40 are lubricated.

  Then, the lubricating oil that has moved to the outside in the radial direction by the action of centrifugal force and finally reached the inner wall surface of the casing 22 gathers in the lower part of the casing 22 by gravity and is discharged from the oil discharge port 22b and is supplied to the lubricating oil reservoir 22d. It is stored in. Thus, since the lubricating oil reservoir 22d is provided between the oil discharge port 22b and the oil passage 22e connected to the rotary pump 51, the lubricating oil is agitated by the agitation of the deceleration unit B by stirring especially during high-speed rotation. Even if the amount of the lubricating oil staying inside and reaching the oil discharge port 22b temporarily decreases, the lubricating oil stored in the lubricating oil storage portion 22d passes through the oil passage 22a of the casing 22 to the motor rotating shaft 24. Since it can recirculate | reflux to the oil path 24a, lubricating oil can be stably supplied to the motor part A and the deceleration part B. FIG. As a result, it is possible to prevent heat generation at various portions of the deceleration portion B.

  In addition, the lubricating oil inside the deceleration part B moves radially outward also by gravity in addition to centrifugal force. Therefore, it is desirable that the in-wheel motor drive device 21 is attached to the electric vehicle 11 so that the lubricating oil reservoir 22d is positioned below the in-wheel motor drive device 21.

  As described above, in the cycloid reducer (decelerator B) of the present embodiment, the lubricating oil flowing through the oil passage 25c extending in the axial direction inside the input shaft 25 is disposed on the outer periphery of the eccentric portions 25a and 25b. The first and second roller bearings 40 and 40 serving as the first rolling bearing Rb1 fitted and the needle roller bearing 72 serving as the second rolling bearing Rb2 fitted to the outer periphery of the inner pin 31, respectively. Oil supply paths F1 and F2 are provided. In this way, the lubricating oil flowing through the oil passage 25c of the input shaft 25 can be directly supplied to the rolling bearing 40 and the needle roller bearing 72.

  In particular, in the present embodiment, an oil passage 25d1 provided in the input shaft 25, a through hole (oil passage 29c) opened in both end surfaces of the counterweight 29 fitted to the input shaft 25, and a radial penetration provided in the stabilizer 70 are provided. The second oil supply passage F2 including the hole (oil passage 70c) and the like is formed, and the oil passages 25d1, 29c, 70c constituting the oil supply passage F2 are provided in the (same) position in the axial direction. The guide member 71 for guiding the lubricating oil discharged from the outer diameter end portion of the oil passage 70c of the stabilizer 70 to the end surface 31c of the inner pin 31 (inlet of the inner oil passage 31e) is disposed, etc. The lubricating oil flowing through the 25 oil passages 25 c can be efficiently supplied to the needle roller bearing 72.

  In the present embodiment, the counter weight 29 is disposed between the rolling bearing 40 fitted to the outer periphery of the eccentric portion 25a and the rolling bearing 37A as the third rolling bearing Rb3 that supports the input shaft 25, and this counter Since the second oil supply passage F2 is configured by the axial through hole (oil passage 29c) provided in the weight 29, a part of the lubricating oil flowing through the second oil supply passage F2 is removed from the outer periphery of the eccentric portion 25a. It is also possible to supply the rolling bearing 40 fitted to the rolling bearing 40 and the rolling bearing 37 </ b> A that supports the input shaft 25.

  On the other hand, the counterweight 29 having axial through-holes (oil passages 29c) opened at both end faces is, for example, a method of stamping a metal plate (pressing), compression-molding a raw material powder, and then sintering it. Etc., and can be obtained by an inexpensive manufacturing method. Moreover, since the oil passage 70c provided in the stabilizer 70 is comprised by the radial direction through-hole, it can be formed easily. Therefore, the second oil supply path F2 that can supply the lubricating oil to the needle roller bearing 72 in the above-described manner can be constructed at a relatively low cost.

  As described above, according to the present invention, while avoiding an increase in cost as much as possible, the roller bearings 40 and 40 as the first rolling bearing Rb1 and the needle roller bearings 72 and 72 as the second rolling bearing Rb2, Can reliably supply a sufficient amount of lubricating oil to the rolling bearing 37A as the third rolling bearing Rb3. Therefore, it is possible to realize a cycloid reduction gear that is relatively low cost and excellent in acoustic performance, durability life, and the like, and thus an in-wheel motor drive device 21 equipped with the same.

  The overall operation principle of the in-wheel motor drive device 21 having the above configuration will be described with reference to FIGS. 1 and 4.

  In the motor part A, for example, the rotor 23b made of a permanent magnet or a magnetic material rotates by receiving an electromagnetic force generated by supplying an alternating current to the coil of the stator 23a. Accordingly, when the input shaft 25 connected to the motor rotation shaft 24 rotates, the curved plates 26 a and 26 b revolve around the rotation axis of the input shaft 25. At this time, the outer pin 27 engages with the curved waveform provided on the outer periphery of the curved plates 26a and 26b in the circumferential direction, and the curved plates 26a and 26b rotate in the direction opposite to the rotation direction of the input shaft 25. Rotate.

  The inner pin 31 inserted into the through hole 30a comes into contact with the inner wall surface of the through hole 30a as the curved plates 26a and 26b rotate. Thereby, the revolution movement 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 bearing portion C via the output shaft 28. At this time, the rotation of the input shaft 25 is transmitted to the output shaft 28 after being decelerated by the speed reduction unit B. Therefore, even when the low torque, high rotation type motor unit A is employed, the rear wheel 14 which is a driving wheel is used. It is possible to transmit the torque required for.

The speed reduction ratio of the speed reduction part B having the above configuration is (Z _A −Z _B ) / Z _B , where Z _{A is} the number of outer pins 27 and Z _B is the number of waveforms provided on the outer peripheral parts of the curved plates 26a and 26b. Is calculated by In the form shown in FIG. 4, since Z _A = 12 and Z _B = 11, a very large reduction ratio of 1/11 can be obtained.

  In this way, by adopting the speed reduction unit B that can obtain a large speed reduction ratio without using a multi-stage configuration, the in-wheel motor drive device 21 having a compact and high speed reduction ratio can be obtained. Further, by providing the needle roller bearings 61 and 72 for rotatably supporting the outer pin 27 and the inner pin 31, the frictional resistance between the curved plates 26a and 26b and the outer pin 27 and the inner pin 31 is reduced. Therefore, the power transmission efficiency in the deceleration part B improves.

  As described above, the in-wheel motor drive device 21 of this embodiment is light and compact as a whole device. Therefore, if the in-wheel motor drive device 21 is mounted on the electric vehicle 11, the unsprung weight can be suppressed, so that the electric vehicle 11 excellent in running stability and NVH characteristics can be realized.

  As described above, the in-wheel motor driving device 21 according to the embodiment of the present invention has been described. However, the in-wheel motor driving device 21 can be variously modified without departing from the gist of the present invention. is there.

  For example, a cycloid pump is used as the rotary pump 51 in the above, but the present invention is not limited to this, and any rotary pump that is driven using the rotation of the output shaft 28 can be used. Furthermore, the rotary pump 51 may be omitted, and the lubricating oil may be circulated only by centrifugal force.

  In the above description, the eccentric portions 25a and 25b are provided at two positions in the axial direction of the input shaft 25. However, the number of formed eccentric portions can be arbitrarily set. For example, the eccentric portions can be provided at three positions in the axial direction of the input shaft 25. In this case, the eccentric portions change the phase by 120 ° so as to cancel the centrifugal force generated by the rotation of the input shaft 25. It is preferable to provide it.

  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 part A to the rear wheel 14. Therefore, the power decelerated as described above is converted into high torque.

  Moreover, although the case where the electric 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 rear wheel 14 is shown, the vehicle decelerates or slopes are reversed. When it falls, the power from the rear wheel 14 side can be converted into high-rotation and low-torque rotation by the speed reduction part B and transmitted to the motor part A, and the motor part A can generate power. . Furthermore, the electric power generated here can be stored in a battery and used as electric power for driving the motor unit A and electric power for operating other electric devices provided in the vehicle.

  In the above description, the present invention is applied to the in-wheel motor drive device 21 that employs a radial gap motor for the motor portion A. However, the present invention is configured such that the stator and the rotor are connected to the motor portion A via an axial gap. The present invention can also be preferably applied to an in-wheel motor drive device that employs an axial gap motor to be opposed.

  Furthermore, the in-wheel motor drive device in which the cycloid reduction gear according to the present invention is applied to the speed reduction part B is not only the rear wheel drive type electric vehicle 11 having the rear wheel 14 as the drive wheel, but also the front wheel 13 as the drive wheel. The present invention can also be applied to a front-wheel drive type electric vehicle and a four-wheel drive type electric vehicle using the front wheels 13 and the rear wheels 14 as drive wheels. In the present specification, “electric vehicle” is a concept including all vehicles that obtain driving force from electric power, and includes, for example, a hybrid vehicle.

  Further, the cycloid reduction gear according to the present invention can be preferably applied to a drive device for an electric vehicle other than the in-wheel motor drive device, for example, a reduction portion of an on-board drive device (not shown).

  The present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the scope of the present invention. The scope of the present invention is not limited to patents. It includes the equivalent meanings recited in the claims and the equivalents recited in the claims, and all modifications within the scope.

DESCRIPTION OF SYMBOLS 11 Electric vehicle 21 In-wheel motor drive device 25 Input shaft 25a, 25b Eccentric part 25c Oil path (axial oil path)
25d1, 25d2, 25d3 oil passage (radial oil passage)
26a, 26b Curved plate 27 Outer pin 28 Output shaft 29 Counterweight 29c Oil passage (through hole)
31 Inner pin 31e Internal oil passage 37A Rolling bearing (third rolling bearing)
40 Rolling bearing (first rolling bearing)
70 Stabilizer 70a Flange 70b Tubular 70c Oil passage (through hole)
71 Guide member 72 Needle roller bearing (second rolling bearing)
A Motor part B Reduction part (Cycloid reduction gear)
C Wheel Bearing F1 First Oil Supply Path F2 Second Oil Supply Path Rb1 First Rolling Bearing Rb2 Second Rolling Bearing Rb3 Third Rolling Bearing

Claims (5)

An input shaft having an eccentric portion, and a curved plate that is rotatably fitted to the outer periphery of the eccentric portion via a first rolling bearing and performs a revolving motion around the rotational axis as the input shaft rotates. An outer pin that engages with the outer periphery of the curved plate to cause the curved plate to rotate, a motion conversion mechanism that converts the rotational motion of the curved plate into a rotational motion of the output shaft, and the shaft of the eccentric portion A counterweight disposed adjacent to the outside in the direction and canceling out an unbalanced inertia couple generated by the rotation of the curved plate, wherein the motion conversion mechanism has a through hole opened at both end faces of the curved plate, and one end of the output In a cycloid reduction gear including an inner pin inserted into the through hole in a state of being fixed to a shaft, and a second rolling bearing fitted to a portion facing the inner wall surface of the through hole of the inner pin,
A first oil supply passage and a second oil supply passage for supplying lubricating oil flowing through an axial oil passage extending in the axial direction inside the input shaft to each of the first rolling bearing and the second rolling bearing;
A radial direction in which the second oil supply passage extends in a radial direction inside the input shaft through a through hole opened at both end surfaces of the counterweight, and the axial oil passage and the through hole in the counterweight communicate with each other And a cycloid reducer characterized by comprising an oil passage. A stabilizer having a flange portion that fixes the other end of the inner pin, and a cylindrical portion that is fitted to the outer periphery of the input shaft via a third rolling bearing;
The cycloid reducer according to claim 1, wherein the second oil supply path includes a through hole opened in an inner diameter surface and an outer diameter surface of the cylindrical portion.   The cycloid reduction gear according to claim 2, wherein the third rolling bearing is disposed adjacent to the outer side of the counterweight in the axial direction. The inner pin has an internal oil passage that opens to the other end surface and the mating surface of the second rolling bearing, and the second oil supply passage is configured to further include the internal oil passage,
A guide member for guiding the lubricating oil discharged from the outer diameter side opening of the through hole of the stabilizer to the other end surface side of the inner pin is disposed on the outer diameter side of the cylindrical portion of the stabilizer. The cycloid reducer according to claim 2 or 3. An in-wheel motor drive device having a motor part, a speed reduction part and a wheel bearing part,
The cycloid reducer according to any one of claims 1 to 4 is applied to the speed reduction unit, and the input shaft constituting the cycloid speed reducer is connected to a rotation shaft of the motor unit so as to transmit torque. An in-wheel motor drive device.

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