JP5620826B2 - Cycloid reducer and in-wheel motor drive device - Google Patents

Description

  The present invention relates to a cycloid reducer and an in-wheel motor drive device using the same, and more particularly to a lubricating oil supply structure in a cycloid reducer.

  Conventionally, a cycloid reducer has been known as a reducer suitable for constituting a reduction part of an in-wheel motor drive device (Patent Documents 1 and 2). This speed reducer will be described with reference to FIGS. 13 to 15 in a state where it is incorporated in the in-wheel motor drive device as a speed reducing portion.

  The in-wheel motor drive device 101 shown in FIG. 13 includes a motor unit A that generates a driving force, a deceleration unit B that receives the rotation of the motor unit A, decelerates the output, and outputs the wheel with the output deceleration. It is comprised by the wheel hub bearing part C which rotates.

  In the in-wheel motor drive device 101 having the above-described configuration, a low-torque and high-rotation motor is adopted as the motor portion A from the viewpoint of making the device compact. On the other hand, the wheel hub bearing portion C requires a large torque to drive the wheels. For this reason, in the reduction part B, the cycloid reduction gear which is compact and can obtain a high reduction ratio is often adopted.

  The motor unit A includes a stator 103 fixed to the motor housing 102 and a rotor 105 attached to the motor shaft 104 inside the stator 103. The stator 103 and the rotor 105 constitute a radial gap motor facing each other with a radial gap. The motor shaft 104 is rotatably supported by the motor housing 102 via rolling bearings 106a and 106b at both front and rear ends.

  The motor shaft 104 is provided with an internal passage 107, and the input shaft 108 of the speed reduction unit B is inserted into the front end of the internal passage 107 and connected integrally. The input shaft 108 is also provided with an internal passage 109, and both the internal passages 107 and 109 communicate with each other.

  The speed reduction part B is constituted by a cycloid speed reducer, and is provided with a pair of eccentric cams 110a and 110b adjacent to each other in the axial direction on the outer diameter surface of the input shaft 108 and having different phases. Curved plates 112a and 112b are rotatably fitted around the eccentric cams 110a and 110b via rolling bearings 111a and 111b. The curved plates 112a and 112b are formed with an arc gear 115 on the outer peripheral surface, and outer pins 113 that engage with the arc gear 115 are provided on the inner peripheral surface of the speed reducer casing 114 so as to be rotatable at regular intervals. The number of outer pins 113 is one more than the number of teeth of the arc gear 115, and a plurality of outer pins 113 are simultaneously engaged with the arc gear 115 (see FIG. 14).

  Further, through holes 130 are provided on the constant radius around the rotation centers of the curved plates 112a and 112b at regular intervals in the circumferential direction, and the inner pins 116 are inserted therethrough. The through hole 130 has a larger diameter than the inner pin 116 by a predetermined amount. One end portion of each inner pin 116 is fixed to the flange portion of the output member 117 of the speed reduction portion B, whereby the rotational motion of the curved plates 112a and 112b is transmitted to the output member 117. The output member 117 and the input shaft 108 are concentric, and a rolling bearing 118 is interposed between the outer diameter surface of the input shaft 108 and the inner diameter surface of the output member.

  The rear end portion of the inner pin 116 is inserted and fixed to the stabilizer 119. The stabilizer 119 is supported on the outer diameter surface of the input shaft 108 so as to be relatively rotatable.

  A lubrication mechanism for supplying lubricating oil to the speed reducing portion constituting members such as the rolling bearings 111a and 111b and the curved plates 112a and 112b provided in the speed reducing portion B is provided on the outer diameter surface of the stabilizer 119 and is a cycloid pump. The rotary pump 120 is provided. The rotary pump 120 rotates integrally with a stabilizer 119 and an output member 117 connected thereto.

  As shown in FIG. 13, the oil supply passage 121 for supplying lubricating oil to the inside of the speed reduction unit B extends rearward along the inside of the motor housing 102 from the discharge port of the rotary pump 120, and the rear end portion of the motor shaft 104. To the internal passage 107, the internal passage 109 of the input shaft 108 of the speed reduction portion B, the input shaft oil supply holes 122a and 122b (see FIG. 15) provided in the radial direction in the input shaft 108 so as to communicate with the internal passage 109, eccentricity It is comprised by the cam part oil supply holes 123a and 123b provided in the cams 110a and 110b, and the inner ring oil supply holes 125a and 125b provided in the inner ring members 124a and 124b of the rolling bearings 111a and 111b.

  The lubricant return passage 126 (see FIG. 13) is configured by a passage that reaches the suction port of the rotary pump 120 through the discharge port 127 provided in the bottom of the reduction gear casing 114 and the lubricant storage unit 128.

  Counterweights 129a and 129b (see FIG. 15) are provided in contact with the outer end surfaces of the eccentric cams 110a and 110b, respectively.

JP 2009-63043 A JP 2009-216190 A

  In the lubrication mechanism of the speed reducing portion B, it is necessary to process the cam portion oil supply holes 123a and 123b in the eccentric cams 110a and 110b, and the inner ring oil supply holes 125a and 125b in the inner ring members 124a and 124b of the rolling bearings 111a and 111b, respectively. .

  However, these oil supply holes 123a, 123b, 125a, 125b have a small diameter (about φ3 mm), and it is difficult to drill such small diameter holes in the eccentric cams 110a, 110b and the inner ring members 124a, 124b. The workability is low and the cost is high.

  In view of the difficulty of drilling in which the oil supply holes constituting the lubrication mechanism are provided in the eccentric cam and the inner ring member, the present invention eliminates the need for drilling. It is an object to improve workability and reduce costs.

  In order to solve the above problems, the present invention includes an eccentric cam provided on an input shaft, a curved plate that is rotatably fitted to an outer peripheral surface of the eccentric cam and has an arc gear on an outer peripheral portion, and the curved plate An outer peripheral engagement member provided on the inner peripheral surface of the housing concentrically with the input shaft, a motion converting mechanism for transmitting the rotational motion of the curved plate to the output member, and lubrication for supplying lubricating oil to each part A circular gear of the curved plate and an outer peripheral engaging member are engaged with each other, and the lubricating mechanism is provided inside the speed reducer through an internal passage of the input shaft and an oil supply hole communicating with the internal passage. In a cycloid reducer having an oil supply passage for supplying lubricating oil, an oil supply groove that communicates the oil supply hole of the input shaft and the inside of the reducer is provided on an axial surface of a reducer component attached to the input shaft. Composition A.

  The process of providing the oil supply groove on the surface of the reduction gear component can be performed by forging or sintering, and the conventional drilling process is not necessary.

  As the speed reducer constituting member, an oil supply plate attached in close contact with one or both end faces of the eccentric cam can be used. An oil supply groove is provided on the axial surface of the oil supply plate, and the surface provided with the oil supply groove is in close contact with the eccentric cam side.

  The above-mentioned eccentric cam can be used as another reduction gear component. An oil supply groove is provided on the axial end surface of the eccentric cam, and the oil supply groove is closed with a lid plate.

  As another reduction gear component, a counterweight attached in close contact with the end face of the eccentric cam can be used. An oil supply groove is provided on the surface of the counterweight on the eccentric cam side.

  As described above, according to the present invention, the oil supply groove is provided on the axial surface of the speed reducer constituting member attached to the cycloid speed reducer input shaft, and the lubricating oil flows into the speed reducer through the oil supply groove. I did it. Thereby, it is not necessary to perforate the speed reducer constituting member, and simpler grooving can be performed. A member with an oil supply groove has an advantage that it can be easily manufactured by forging, sintering, or the like.

FIG. 1 is a cross-sectional view of the in-wheel motor drive device according to the first embodiment. FIG. 2 is an enlarged cross-sectional view of the deceleration portion same as above. 3 is a cross-sectional view taken along line X1-X1 of FIG. 4A is a partially enlarged cross-sectional view of the same, FIG. 4B is a front view of the fueling plate, and FIG. 4C is a cross-sectional view taken along line X2-X2 of FIG. 4B. FIG. 5 is a front view of the rotary pump. FIG. 6 is a partially enlarged cross-sectional view of the second embodiment. 7 (a) is an enlarged front view of the eccentric cam, FIG. 7 (b) is a sectional view taken along line X3-X3 in FIG. 7 (a), and FIG. 7 (c) is a front view of the inner ring member. 7 (d) is a cross-sectional view taken along line X4-X4 of FIG. 7 (c). FIG. 8A is a front view of a modified example of the eccentric cam of the second embodiment, and FIG. 8B is a cross-sectional view taken along line X5-X5 in FIG. 8A. Fig.9 (a) is a front view of the modification of the inner ring member of 2nd Embodiment, FIG.9 (b) is sectional drawing of the X6-X6 line | wire of Fig.9 (a). FIG. 10 is a partially enlarged cross-sectional view of the third embodiment. FIG. 11A is a partially enlarged cross-sectional view of the fourth embodiment, and FIG. 11B is a front view of the counterweight of FIG. 11A. 12A is a partially enlarged cross-sectional view of the fifth embodiment, FIG. 12B is a front view of one member of FIG. 12A, and FIG. 12C is FIG. It is sectional drawing of X7-X7 line | wire. FIG. 13 is a cross-sectional view of a conventional in-wheel motor drive device. 14 is a cross-sectional view taken along line X8-X8 in FIG. FIG. 15 is a partially enlarged sectional view of FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  As shown in FIG. 1, the in-wheel motor drive device 11 according to the first embodiment of the present invention includes a motor unit A that generates a driving force, and a deceleration unit B that decelerates and outputs the rotation of the motor unit A. And the wheel hub bearing part C which transmits the output of the deceleration part B to a wheel is provided. The motor part A is incorporated in the motor housing 12, and the reduction part B is incorporated in the reduction part housing 13. A speed reduction unit housing 13 is connected and fixed to the front end of the motor housing 12 by a bolt 14.

  The motor part A includes a stator 15 fixed to the motor housing 12 and a rotor 17 integrated with the motor shaft 16, and the stator 15 and the rotor 17 constitute a radial gap motor facing in the radial direction. The rotor 17 is fixed to the flange 19 of the motor shaft 16 by bolts 18. The motor shaft 16 is rotatably supported by the motor housing 12 via rolling bearings 21a and 21b at both front and rear ends.

  The motor shaft 16 is provided with an internal passage 22, and the input shaft 23 of the speed reduction unit B is connected to the front end of the internal passage 22. The input shaft 23 is also provided with an internal passage 25, and both the internal passages 22 and 25 communicate with each other.

  The input shaft 23 is provided with a pair of eccentric cams 27a and 27b adjacent to each other inside the speed reduction portion B (see FIGS. 2 and 4). These eccentric cams 27a and 27b are provided with a phase difference of 180 ° so that the centrifugal forces due to the eccentric motion cancel each other.

  The speed reduction part B includes an annular casing 26 fitted and fixed to the inner diameter surface of the speed reduction part housing 13 (see FIG. 2), and each member constituting the speed reduction part B is incorporated in the casing 26.

  The members constituting the deceleration portion B include the eccentric cams 27a and 27b, the curved plates 29a and 29b rotatably held by the eccentric cams 27a and 27b via the rolling bearings 28a and 28b, and the inner diameter surface of the casing 26. A plurality of outer pins 31 (see FIG. 3) fixed at equal intervals along the axis, a motion conversion mechanism for transmitting the rotational motion of the curved plates 29a and 29b to the output member 32, and the axially outer sides of the eccentric cams 27a and 27b. There are counterweights 33a, 33b and the like attached to the input shaft 23 adjacent to each other.

  The outer pin 31 functions as an outer peripheral engagement member that engages with the arcuate gear 30 formed on the outer peripheral portion of the curved plates 29a and 29b. In addition, the speed reduction part B is provided with a speed reduction part lubrication mechanism that supplies lubricating oil to the members in the casing 26. Moreover, the output member 32 fulfill | performs the mechanism as a wheel side rotation member.

  The output member 32 has a flange portion 32a and a shaft portion 32b (see FIGS. 2 and 3). One end portions of a plurality of inner pins 34 are inserted into and fixed to the flange portion 32a at equal intervals on the circumference around the rotation axis of the output member 32. The shaft portion 32b is fitted and fixed to the inner diameter surface of the wheel hub 35, and transmits the output of the speed reduction portion B to the wheel. A rolling bearing 36 is interposed between the inner diameter surface of the flange portion 32a of the output member 32 and the input shaft 23, so that the input shaft 23 and the output member 32 are held concentrically and relatively rotatable.

  The other end portion of the inner pin 34 is inserted and supported by a flange portion 37 a of the stabilizer 37. The stabilizer 37 has a cylindrical portion 37 b provided on the inner diameter of the flange portion 37 a, and the cylindrical portion 37 b is rotatably fitted to the outer diameter surface of the front end portion of the motor shaft 16 via the needle roller bearing 38. Yes.

  As shown in FIG. 3, the curved plates 29a and 29b have an arc gear 30 formed of a trochoidal curve such as an epitrochoid on the outer periphery, and a plurality of penetrating through from one end face to the other end face. A through hole 39 is provided. The through holes 39 are provided in the same number and at the same intervals as the inner pins 34 on the circumference around the rotation axis of the curved plates 29a and 29b, and the inner pins 34 are provided in the respective through holes 39. It is inserted.

  The curved plates 29a and 29b are rotatably supported by eccentric cams 27a and 27b via rolling bearings 28a and 28b, respectively. The phases of the curved plates 29a and 29b are also shifted by 180 ° in the same direction as the eccentric cams 27a and 27b.

  As shown in FIG. 4, the rolling bearings 28a and 28b are directly connected to the inner ring members 40a and 40b fitted to the outer diameter surfaces of the eccentric cams 27a and 27b and the inner diameter surfaces of the through holes 39 of the curved plates 29a and 29b. This is a cylindrical roller bearing comprising a formed outer ring raceway surface 41 (see FIG. 3) and a plurality of cylindrical rollers 28c and 28d interposed therebetween. Flange portions 40c and 40d are provided on the inner surfaces (surfaces facing each other) of the inner ring members 40a and 40b, respectively.

  As shown in FIGS. 2 and 3, the outer pins 31 are provided along the inner peripheral surface of the casing 26 at equal intervals on a circumferential track centering on the rotation axis of the input shaft 23. Both end portions of the outer pin 31 are rotatably supported by thick portions 26 a and 26 b on both sides of the casing 26 via needle roller bearings 43. Further, balls 44 are held on both end faces of the outer pin 31, and the friction in the thrust direction is reduced by bringing the balls 44 into contact with the closing ring plate 45. The number of the outer pins 31 is one more than the number of teeth of the arcuate gears 30 of the curved plates 29a and 29b, and a plurality of outer pins 31 are simultaneously engaged with the arcuate gears 30.

  When a revolving motion is applied to the curved plates 29a and 29b by the input shaft 23 and the eccentric cams 27a and 27b integrated therewith, the arc gear 30 and the outer pin 31 are engaged, and the curved plates 29a and 29b are rotated. Cause it to occur.

  The counterweights 33a and 33b are arranged at positions adjacent to the outer sides of the eccentric cams 27a and 27b in order to cancel out the unbalanced inertia couple generated by the rotation of the eccentric cams 27a and 27b and the curved plates 29a and 29b. , 27b and 180 °, respectively, and are attached in an eccentric state.

  The motion conversion mechanism described above includes a plurality of inner pins 34 fixed to the output member 32 and through holes 39 provided in the curved plates 29a and 29b. The inner diameter dimension of the through hole 39 is a predetermined amount (the amount of eccentricity of the eccentric cams 27a and 27b) from the outer diameter dimension of the inner pin 34 (refers to "maximum outer diameter including needle roller bearings 46a and 46b"). (2 times) is set larger.

  The inner pins 34 are provided at equal intervals on a circumferential track centering on the rotational axis of the output member 32. As described above, one end of the inner pin 34 is fixed to the output member 32, and the other end. Is fixed to the stabilizer 37. In order to reduce the frictional resistance with the curved plates 29a, 29b, needle roller bearings 46a, 46b are provided in portions of the curved plates 29a, 29b that pass through the through holes 39, and each inner pin 34 has its needle roller bearing. It partially contacts the through hole 39 via 46a and 46b.

  The speed reducer lubrication mechanism is a mechanism that supplies lubricating oil to the speed reducer B, and is a rotation provided on the outer diameter surface of the cylindrical portion 37b of the stabilizer 37 at the inner diameter portion of the wall surface of the motor housing 12 on the speed reducer B side. The pump 47 (see FIGS. 1 and 2), an oil supply passage 49 extending from the discharge port 48 to the inside of the speed reduction unit B, and a return path 52 returning from the speed reduction unit B to the suction port 51 after finishing the lubrication.

  The oil supply passage 49 reaches the rear end of the motor shaft 16 along the inner side of the motor housing 12, and corresponds to the internal passages 22 and 25 of the motor shaft 16 and the input shaft 23 and the eccentric cams 27a and 27b of the input shaft 23. It passes through oil supply holes 53a and 53b (see FIGS. 2 and 4) provided in the radial direction at the position.

  As shown in FIG. 4, the oil supply plates 54a and 54b are fixed to the input shaft 23 so as to be in close contact with the outer end surfaces of the inner ring members 40a and 40b of the eccentric cams 27a and 27b and the rolling bearings 28a and 28b. Here, the “outer end surface” refers to the end surface on the side of the wheel hub bearing C in the eccentric cam 27a and the inner ring member 40a, and the end surface on the motor A side in the eccentric cam 27b and the inner ring member 40b. same as below.

  Oil supply grooves 55 (see FIGS. 4A to 4C) provided on the inner surfaces of the oil supply plates 54 a and 54 b communicate with the oil supply holes 53 a and 53 b and the inside of the speed reduction portion B. As a result, the lubricating oil in the oil supply passage 49 is supplied into the speed reduction portion B.

  Since the inner side surfaces 54c and 54d (see FIG. 4B) along the outer peripheral surfaces of the oil supply plates 54a and 54b are in sliding contact with the cylindrical rollers 28c and 28d, a surface treatment is applied to impart wear resistance and slipperiness. It is desirable. Examples of the surface treatment include electroless plating and hard chrome plating.

  The return passage 52 for the lubricating oil is provided with a discharge port 56 (see FIGS. 1 and 2) provided at the bottom of the speed reduction unit housing 13 and a lubricating oil provided at the outer bottom of the speed reduction unit housing 13 and communicated with the discharge port 56. The reservoir 57 and a passage from the lubricant reservoir 57 to the suction port 51 are configured.

  As shown in FIG. 4A, the oil supply plates 54a and 54b are sandwiched between the outer end surface of the eccentric cam 27a and the counterweight 33a, and between the outer end surface of the eccentric cam 27b and the counterweight 33b, respectively. . As shown in FIGS. 4 (b) and 4 (c), the inner surfaces of the oil supply plates 54a and 54b are constituted by discs that cover the range up to the outer diameter of the inner ring member 40a of the rolling bearing 28a, and input to the eccentric position thereof. A D-cut shaft hole 58 through which the shaft 23 passes is provided, and the oil supply grooves 55 are provided radially from an annular groove 59 around the shaft hole 58. Providing such oil supply plates 54a and 54b eliminates the need to process oil supply holes in the eccentric cams 27a and 27b and the inner ring members 40a and 40b.

  As shown in FIG. 5, the rotary pump 47 includes an inner rotor 60 that rotates integrally with the stabilizer 37, an outer rotor 61 that rotates following the rotation of the inner rotor 60, a pump chamber 62, and an oil supply passage 49. The cycloid pump includes a discharge port 48 communicating with the suction port 51 and a suction port 51 communicating with the return passage 52.

  Inner rotor 60 has a tooth profile formed of a cycloid curve on the outer diameter surface. Specifically, the shape of the tooth tip portion 60a is an epicycloid curve, and the shape of the tooth gap portion 60b is a hypocycloid curve. The inner rotor 60 is fitted to the outer diameter surface of the cylindrical portion 37 b of the stabilizer 37 and rotates integrally with the output member 32 via the inner pin 34.

  The outer rotor 61 has a tooth profile formed of a cycloid curve on the inner diameter surface. Specifically, the shape of the tooth tip portion 61a is a hypocycloid curve, and the shape of the tooth gap portion 61b is an epicycloid curve. The outer rotor 61 is rotatably supported by the motor housing 12. When using the speed reduction part B as an independent speed reducer, the outer rotor 61 is supported by the speed reducer housing.

  The inner rotor 60 rotates around the rotation center c1. On the other hand, the outer rotor 61 rotates around a rotation center c2 different from the rotation center c1 of the inner rotor. Further, when the number of teeth of the inner rotor 60 is n, the number of teeth of the outer rotor 61 is (n + 1). In this embodiment, n = 5.

  A plurality of pump chambers 62 are provided in the space between the inner rotor 60 and the outer rotor 61. When the inner rotor 60 rotates using the rotation of the output member 32, the outer rotor 61 rotates in a driven manner. At this time, since the inner rotor 60 and the outer rotor 61 rotate about different rotation centers c1 and c2, the volume of the pump chamber 62 changes continuously. As a result, the lubricating oil flowing from the suction port 51 is pumped from the discharge port 48 to the oil supply passage 49.

  The lubricating oil reservoir 57 can temporarily store lubricating oil that cannot be completely discharged by the rotary pump 47 during high-speed rotation. As a result, an increase in torque loss of the deceleration unit B can be prevented. On the other hand, during low-speed rotation, the lubricating oil stored in the lubricating oil reservoir 57 can be pushed out to the oil supply passage 49 even if the amount of lubricating oil reaching the discharge port 56 decreases. As a result, the lubricating oil can be stably supplied to the deceleration unit B.

  The flow of the lubricating oil in the deceleration portion B having the above configuration will be described. First, the lubricating oil discharged from the rotary pump 47 and reaching the internal passage 25 of the input shaft 23 through the internal passage 22 of the motor shaft 16 constituting the oil supply passage 49 is applied to the pressure of the rotary pump 47 and the rotation of the input shaft 23. Due to the accompanying centrifugal force, the oil flows into the inside of the speed reduction portion B through the oil supply holes 53 a and 53 b and the oil supply groove 55.

  Since centrifugal force further acts on the lubricating oil flowing into the speed reduction part B, the roller bearings 28a and 28b, the needle roller bearings 46a and 46b around the inner pin 34, and the needle roller bearings 46a and 46b and the penetrating shafts. It moves radially outward while lubricating the contact portion with the hole 39, the contact portion between the arc gear 30 of the curved plates 29a and 29b and the outer pin 31, and the like.

  The lubricating oil that has reached the inner wall surface of the speed reduction unit housing 13 is discharged from the discharge port 56 and stored in the lubricating oil storage unit 57. The lubricating oil stored in the lubricating oil storage part 57 is sucked by the rotary pump 47 and returns to the suction port 51 through the return passage 52.

  The oil supply passage 49 also functions as a coolant for cooling the rolling bearings 21 a and 21 b and the motor part A while passing from the motor housing 12 through the internal passages 22 and 25 of the motor shaft 16 and the input shaft 23.

  The speed reducer lubrication mechanism includes a cooling water passage 63 that cools the lubricating oil that passes through the oil supply passage 49. The cooling water path 63 is provided in the circumferential direction on the outer peripheral surface of the motor housing 12, and cools the lubricating oil in the oil supply passage 49 passing through the inner side thereof, and also cools the motor part A.

  As shown in FIG. 1, the wheel hub bearing portion C includes a wheel hub 35 fixedly connected to the output member 32 of the speed reduction portion B, and a wheel hub bearing 64 that rotatably holds the wheel hub 35 with respect to the speed reduction portion housing 13. Is provided. The output member 32 is inserted into the inner surface of the wheel hub 35 and is splined, and the output member 32 and the wheel hub 35 are coupled by fastening the tip of the output member 32 exposed from the wheel hub 35 with a nut 65. ing.

  The operation principle of the in-wheel motor drive device 11 having the above configuration will be described in detail. The motor unit A receives an electromagnetic force generated by supplying an alternating current to the coil of the stator 15, and the rotor 17 constituted by a permanent magnet or a magnetic material rotates. At this time, the rotor 17 rotates at a higher speed as a higher frequency voltage is applied to the coil.

  As a result, when the motor shaft 16 connected to the rotor 17 and the input shaft 23 integrated therewith rotate, the eccentric cams 27a and 27b perform eccentric rotational movement, so that the curved plates 29a and 29b become the rotational axis of the input shaft 23. The revolving motion is performed at the speed of the input shaft 23 around the center. At this time, the plurality of outer pins 31 engage with the arcuate gears 30 of the curved plates 29a and 29b to cause the curved plates 29a and 29b to rotate at a low speed in the direction opposite to the rotation direction of the input shaft 23. .

  The inner pin 34 inserted through the through hole 39 partially contacts the inner wall surface of the through hole 39 as the curved plates 29a and 29b rotate. Thereby, the revolution movement of the curved plates 29a and 29b is not transmitted to the inner pin 34, and only the rotational motion of the curved plates 29a and 29b is transmitted to the wheel hub bearing portion C via the output member 32.

  In this way, the rotation of the motor shaft 16 is decelerated by the deceleration unit B and transmitted to the output member 32. Therefore, even when the low torque, high rotation type motor unit A is employed, the necessary torque is transmitted to the wheels. It becomes possible to do.

  Note that the reduction ratio of the speed reduction portion B having the above-described configuration is calculated as (ZA−ZB) / ZB, where ZA is the number of outer pins 31 and ZB is the number of arc gears 30 of the curved plates 29a and 29b. In the embodiment shown in FIG. 1, since ZA = 12, ZB = 11, the reduction ratio is 1/11, and a very large reduction ratio can be obtained.

  In this way, by adopting the speed reduction unit B that can obtain a large speed reduction ratio without using a multistage configuration, the in-wheel motor drive device 11 having a compact and high speed reduction ratio can be obtained. In addition, since the outer pin 31 is supported by the needle roller bearing 43 and the needle roller bearings 46a and 46b are provided at positions where they contact the curved plates 29a and 29b of the inner pin 34, the frictional resistance is reduced. The transmission efficiency of the deceleration part B is improved.

  By employing the in-wheel motor drive device 11 according to the first embodiment in an electric vehicle, the unsprung weight can be suppressed. As a result, an electric vehicle with excellent running stability can be obtained.

  In the first embodiment described above, the example in which the oil supply passage 49 is provided inside the motor housing 12 has been shown. However, the present invention is not limited to this, and for example, a circulation oil passage is provided outside the in-wheel motor drive device 11. It may be provided.

  In the first embodiment, the example in which the rotary pump 47 is driven by using the rotation of the output member 32 has been described. However, the rotary pump 47 may be driven by using the rotation of the motor shaft 16. it can. However, since the rotational speed of the motor shaft 16 is larger than that of the output member 32 (11 times in the above embodiment), the durability of the rotary pump 47 may be reduced. Further, even when connected to the output member 32, a sufficient discharge amount can be ensured. From these viewpoints, the rotary pump 47 is preferably driven by using the rotation of the output member 32.

  Moreover, although the example of the cycloid pump was shown as the rotary pump 47, not only this but the rotary pump driven using the rotation of the output member 32 is employable.

  In addition, although two curved plates 29a and 29b of the deceleration unit B are provided with a 180 ° phase change, the number of the curved plates can be arbitrarily set. For example, when three curved plates are provided, 120 are provided. ° It is recommended to change the phase.

  Moreover, although the above-mentioned motion conversion mechanism has shown the example comprised by the inner pin 34 fixed to the output member 32, and the through-hole 39 provided in the curve boards 29a and 29b, it is not restricted to this, It is possible to adopt an arbitrary configuration capable of transmitting the rotation of the speed reduction unit B to the wheel hub 35. For example, it may be a motion conversion mechanism composed of an inner pin fixed to a curved plate and a hole formed in the wheel side rotation member.

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

  In the above description of the operation, 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 wheels. Conversely, the vehicle decelerates. When going down or down a hill, the power from the wheel side may be converted into high-rotation and low-torque rotation by the reduction unit B and transmitted to the motor unit A, and the motor unit A may generate power. Furthermore, the electric power generated here may be stored in a battery, and the motor unit A may be driven later, or used for the operation of other electric devices provided in the vehicle.

  Furthermore, although the example of the cylindrical roller bearing was shown as rolling bearing 28a, 28b which supports the curve plates 29a, 29b, it is not restricted to this, For example, a sliding bearing, a cylindrical roller bearing, a tapered roller bearing, a needle roller bearing, Spherical roller bearings, deep groove ball bearings, angular contact ball bearings, 4-point contact ball bearings, etc., regardless of whether they are plain bearings or rolling bearings, regardless of whether the rolling element is a roller or a ball, Furthermore, any bearing can be applied regardless of whether it is a double row or a single row. Similarly, any type of bearing can be adopted for bearings arranged in other locations.

  However, the deep groove ball bearing has a higher allowable limit speed than the cylindrical roller bearing, but has a low load capacity. Therefore, in order to obtain a necessary load capacity, a large deep groove ball bearing must be employed. Therefore, from the viewpoint of making the in-wheel motor drive device 11 compact, cylindrical roller bearings are suitable for the rolling bearings 28a and 28b.

  Moreover, although the example which employ | adopted the radial gap motor as the motor part A was shown, the motor of arbitrary structures is applicable not only to this. For example, it may be an axial gap motor including a stator fixed to the housing and a rotor disposed at a position facing the inner side of the stator with a gap in the axial direction.

  Moreover, although the example of the in-wheel motor drive device 11 which employ | adopted the cycloid deceleration mechanism as the deceleration part B was shown, it is not restricted to this but arbitrary deceleration mechanisms are employable. For example, a planetary gear reduction mechanism, a parallel shaft gear reduction mechanism, or the like is applicable.

  Next, regarding the structure for supplying the lubricating oil from the internal passage 25 of the input shaft 23 to the speed reducer B, other embodiments (second to fifth embodiments) are shown in FIGS. Based on In either case, the eccentric cams 27a and 27b and the inner ring members 40a and 40b of the rolling bearings 28a and 28b do not need to be drilled.

  That is, in the second embodiment shown in FIG. 6, the oil supply groove 55 is provided directly on the outer end surfaces of the eccentric cams 27a, 27b and the outer end surfaces of the inner ring members 40a, 40b of the rolling bearings 28a, 28b, and the lid plate 67a. , 67b closes the open end face of the oil supply groove 55. The lid plates 67a and 67b are sandwiched between the eccentric cam 27a and the counterweight 33a, and between the eccentric cam 27b and the counterweight 33b, respectively.

  Also in this case, since the inner side surfaces 67c and 67d along the outer peripheral surface of the lid plates 67a and 67b are in sliding contact with the rollers 28c and 28d, it is desirable to perform a surface treatment for imparting wear resistance and slipperiness.

  On the outer end surfaces of the eccentric cams 27a and 27b, as shown in FIG. 7A, eccentric cam oil supply grooves 55a and 55b having a width w1 extending radially in four directions from the center of the eccentric hole 68 having the D-cut portion. Provided. Further, an inner ring oil supply groove 50a having a constant width is provided on the outer end surface of the inner ring member 40a with a constant pitch width w2 over the entire circumference.

  w1 and w2 are formed to be substantially equal, and the eccentric cam oil supply grooves 55a and 55b and the inner ring oil supply grooves 50a and 50b communicate with each other regardless of the direction of rotation of the inner ring member 40a. The eccentric cam oil supply grooves 55a and 55b and the inner ring oil supply grooves 50a and 50b communicated with each other constitute the oil supply groove 55.

  The eccentric cams 27a and 27b can be formed of an integral member joined at the inner end face portions that are in contact with each other as in the modification shown in FIGS. 8 (a) and 8 (b). In this case, eccentric cam oil supply grooves 55a and 55b are provided on both outer end surfaces. Since both the eccentric cams 27a and 27b are integrated, the number of parts is reduced.

  Further, as in the other modified examples shown in FIGS. 9A and 9B, the eccentric cam 27a and the inner ring member 40a, and the eccentric cam 27b and the inner ring member 40b can be respectively integrated. In this case, raceway surfaces 40e and 40f are formed on the outer peripheral surface, respectively. According to this structure, the number of parts is reduced, and only four oil supply grooves 55 communicating with the eccentric hole 68 need be provided.

  In the case of the third embodiment shown in FIG. 10, the configuration in which the oil supply plates 54a and 54b with the oil supply grooves 55 provided on the inner surface are the same as in the case of the first embodiment (see FIG. 4). is there. In the case of the third embodiment, the flange portions 40c and 40d (see FIG. 4A) of the inner ring members 40a and 40b are omitted, and flange plates 69a and 69b are provided instead. The flange plates 69a and 69b have an outer diameter that matches the outer diameter of the lung portions 40c and 40d, and are attached in close contact with the eccentric cams 27a and 27b and the inner ring members 40a and 40b. Since the flange plates 69a and 69b serve as the flange portions 40c and 40d, the structure of the inner ring members 40a and 40b is simplified.

  In the case of the fourth embodiment shown in FIG. 11, oil supply grooves 55 are respectively provided on the opposing inner surfaces of counterweights 33a, 33b provided in close contact with the outer end surfaces of the eccentric cams 27a, 27b. is there. As shown in FIG. 11 (b), a radial oil supply groove 55 communicating with the annular groove 71 around the shaft hole 70 of each counterweight 33a, 33b is provided.

  In the case of the fifth embodiment shown in FIG. 12, the counterweights 33a and 33b and the oil supply plates 54a and 54b in the first embodiment (see FIG. 4) are integrated.

  Although not shown, the counterweights 33a and 33b and the cover plates 67a and 67b can be integrated even in the case of the second embodiment shown in FIG. Also in the case of the third embodiment shown in FIG. 10, the counterweights 33a and 33b and the oil supply plates 54a and 54b can be integrated.

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

A Motor part B Deceleration part C Wheel hub bearing part 11 In-wheel motor drive device 12 Motor housing 13 Deceleration part housing 14 Bolt 15 Stator 16 Motor shaft 17 Rotor 18 Bolt 19 Flange 21a, 21b Rolling bearing 22 Internal passage 23 Input shaft 25 Inside Passage 26 Casing 26a, 26b Thick part 27a, 27b Eccentric cam 28a, 28b Rolling bearing 28c, 28d Cylindrical roller 29a, 29b Curved plate 30 Arc gear 31 Outer pin 32 Output member 32a Flange part 32b Shaft part 33a, 33b Counterweight 34 Inner pin 35 Wheel hub 36 Rolling bearing 37 Stabilizer 37a Flange portion 37b Cylindrical portion 38 Needle roller bearing 39 Through hole 40a, 40b Inner ring member 40c, 40d Flange portion 40e, 40f Raceway surface DESCRIPTION OF SYMBOLS 1 Outer ring raceway surface 43 Needle roller bearing 44 Ball 45 Closure ring plate 46a, 46b Needle roller bearing 47 Rotary pump 48 Discharge port 49 Oil supply passage 50a, 50b Inner ring oil supply groove 51 Inlet port 52 Return passage 53a, 53b Oil supply hole 54a, 54b Oil supply plate 54c, 54d Inner side surface 55 Oil supply groove 55a, 55b Eccentric cam oil supply groove 55b Inner ring oil supply groove 56 Discharge port 57 Lubricating oil storage part 58 Shaft hole 59 Annular groove 60 Inner rotor 60a Tooth tip part 60b Tooth groove part 61 Outer rotor 61a Tooth tip portion 61b Tooth groove portion 62 Pump chamber 63 Cooling channel 64 Wheel hub bearing 65 Nut 67a, 67b Cover plate 67a, 67b Inner side surface 68 Eccentric hole 69a, 69b Flange plate 70 Shaft hole 71 Annular groove

Claims (10)

An eccentric cam provided on the input shaft, a curved plate that is rotatably fitted to the outer peripheral surface of the eccentric cam and has an arc gear on the outer peripheral portion, and an inner side of the housing that is concentric with the input shaft outside the curved plate The outer peripheral engagement member provided on the peripheral surface, a motion conversion mechanism that transmits the rotation of the curved plate to the output member, and a lubrication mechanism that supplies lubricating oil to each part, and the arc of the curved plate A cycloid speed reducer provided with a gear and an outer peripheral engagement member, wherein the lubricating mechanism includes an internal passage of the input shaft and an oil supply passage for supplying lubricating oil into the reducer through an oil supply hole communicating with the internal passage. The eccentric cams having opposite phases to the eccentric cams are arranged close to each other in the axial direction, and the curved plates are rotatably fitted to the eccentric cams via rolling bearings, respectively, on one or both end faces of the eccentric cams. , Install the oil plate adhesion state, on the surface in close contact with the eccentric cam of the oil supply plate, cycloidal speed reducer, characterized in that a lubrication groove for communicating the internal oil supply hole and reducer of the input shaft. By matching the size of the outer diameter of the fuel supply plate flange outer diameter of the inner ring member of the rolling bearing, cycloid decelerating according the flange portion to claim 1, characterized in that the alternative by the fuel supply plate Machine. The cycloid reduction gear according to claim 1 or 2 , wherein the oil supply plate and a counterweight provided adjacent to each other in the axial direction are integrated. The cycloid reduction gear according to any one of claims 1 to 3 , wherein a surface treatment for imparting wear resistance and slipperiness is performed on a contact surface of the oil supply plate with the rolling element of the rolling bearing. . An eccentric cam provided on the input shaft, a curved plate that is rotatably fitted to the outer peripheral surface of the eccentric cam and has an arc gear on the outer peripheral portion, and an inner side of the housing that is concentric with the input shaft outside the curved plate The outer peripheral engagement member provided on the peripheral surface, a motion conversion mechanism that transmits the rotation of the curved plate to the output member, and a lubrication mechanism that supplies lubricating oil to each part, and the arc of the curved plate A cycloid speed reducer provided with a gear and an outer peripheral engagement member, wherein the lubricating mechanism includes an internal passage of the input shaft and an oil supply passage for supplying lubricating oil into the reducer through an oil supply hole communicating with the internal passage. The eccentric cams having opposite phases to the eccentric cams are arranged close to each other in the axial direction, and the curved plates are rotatably fitted to the eccentric cams via rolling bearings, respectively, on one or both end faces of the eccentric cams. , The oil supply groove for communicating the reducer inside the oil supply hole fill force shaft is provided, on the end face of the eccentric cam provided with the oil supply groove, cycloidal speed reducer, characterized in that is brought into close contact with the lid plate. The cycloid deceleration according to claim 5 , wherein the collar portion is replaced with the lid plate by matching the outer diameter of the lid plate with the outer diameter of the collar portion of the inner ring member of the inner ring member. Machine. The cycloid reduction gear according to claim 5 or 6 , wherein the lid plate and a counterweight provided adjacent to each other in the axial direction are integrated. The cycloid reducer according to any one of claims 5 to 7 , wherein a surface treatment for imparting wear resistance and slipperiness is performed on a contact surface of the lid plate with a rolling element of the rolling bearing. . An eccentric cam provided on the input shaft, a curved plate that is rotatably fitted to the outer peripheral surface of the eccentric cam and has an arc gear on the outer peripheral portion, and an inner side of the housing that is concentric with the input shaft outside the curved plate The outer peripheral engagement member provided on the peripheral surface, a motion conversion mechanism that transmits the rotation of the curved plate to the output member, and a lubrication mechanism that supplies lubricating oil to each part, and the arc of the curved plate A cycloid speed reducer provided with a gear and an outer peripheral engagement member, wherein the lubricating mechanism includes an internal passage of the input shaft and an oil supply passage for supplying lubricating oil into the reducer through an oil supply hole communicating with the internal passage. The eccentric cams having opposite phases to the eccentric cams are arranged close to each other in the axial direction, and the curved plates are rotatably fitted to the eccentric cams via rolling bearings, respectively, on one or both end faces of the eccentric cams. , Mounting in close contact with counter weights, cycloidal speed reducer, characterized in that the counter on the inner surface of the eccentric cam side of the weight, provided the oil supply groove for communicating the reducer inside the oil supply hole of the input shaft. An in-wheel motor comprising a motor unit, a deceleration unit that decelerates rotation of the motor unit, a housing that holds the motor unit and the deceleration unit, and a wheel hub bearing unit that is connected and fixed to an output member of the deceleration unit The in-wheel motor drive device characterized by using the cycloid reducer in any one of Claim 1 to 9 as the said deceleration part in a drive device.

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