JP2012034481A - Vehicle motor driving apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of components and the unit manufacturing cost without complicating the process of a lubricating oil cooling water passage formed in a motor of an electric vehicle.SOLUTION: A motor case 22 is formed of a bottomed cylindrical motor housing 22a whose back surface side for housing a stator 23 and a rotor 24 is openable, and a bottomed cylindrical rear cover 22b formed integrally with a cylindrical part for mating with the interior of a cylindrical part of the motor housing 22a from the back surface side. A water passage groove 61a is formed on an outer peripheral surface of the cylindrical part of the rear cover. By mating the rear cover 22b with the cylindrical part of the motor housing 22a, a cooling water passage 61 is formed.

Description

  The present invention relates to a motor drive device for an electric vehicle or a hybrid electric vehicle.

  2. Description of the Related Art Conventionally, as a motor drive device 101 for an electric vehicle, for example, there is one described in Japanese Patent Laid-Open No. 2009-174593 (Patent Document 1).

  This motor drive device 101 is an in-wheel motor drive device. As shown in FIG. 10, a motor unit 103 that generates a drive force in a motor case 102 attached to a vehicle body, and a wheel hub bearing connected to a wheel. Part 104 and a speed reduction part 105 that decelerates the rotation of motor part 103 and transmits it to wheel hub bearing part 104.

  In the motor drive device 101 as described above, the lubricating oil cooling water channel 106 is provided on the outer periphery of the motor case 102 to improve the cooling performance.

  The motor case 102 includes a bottomed cylindrical motor housing 102a that houses the stator 107 and the rotor 108 of the motor unit 103, a rear cover 102b that has a support unit for the motor output shaft 109, and a cylinder that is fitted to the outer periphery of the motor housing 102a. It consists of member 102c.

  The cylindrical member 102c is a cover of a spiral water channel groove formed on the outer periphery of the motor housing 102a, and is a member necessary for forming the lubricating oil cooling water channel 106.

JP 2009-174593 A

  However, in order to form the lubricating oil cooling water channel 106 in the motor case 102, it is necessary to divide the motor case 102 into three members, that is, the motor housing 102a, the rear cover 102b, and the cylindrical member 102c as described above. The number of parts and the assembly process increased.

  Therefore, an object of the present invention is to provide a structure of a motor case that can reduce the number of parts and the unit manufacturing cost without complicating the processing of the lubricating oil cooling water channel.

  In order to solve the above-described problems, the present invention provides a motor case having a cooling water channel on the outer peripheral portion, a bottomed cylindrical motor housing that opens on the back side that accommodates the stator and the rotor, and a cylindrical portion of the motor housing. It is characterized in that it is formed by a bottomed cylindrical rear cover integrally formed with a cylindrical part fitted from the back side inside, and a water channel groove is formed on the outer peripheral surface of the cylindrical part of the rear cover.

  In addition, a motor case having a cooling water channel on the outer peripheral portion, a bottomed cylindrical motor housing that opens on the back side that accommodates the stator and the rotor, and a cylindrical shape that fits from the back side to the outside of the cylindrical portion of the motor housing It may be formed by a bottomed cylindrical rear cover integrally formed with the part, and a water channel groove may be formed on the outer peripheral surface of the cylindrical part of the motor housing.

  An oil passage for lubricating oil can be formed in the bottomed cylindrical motor housing and the rear cover.

  The bottomed cylindrical motor housing and the rear cover can be formed by die casting or casting.

  The motor case of this invention can be used for the motor part of an in-wheel motor drive device.

  A motor driving device having a one-motor structure includes a motor unit using the motor case of the present invention, a speed reducing unit that decelerates and outputs the rotation of the motor unit, and a differential that transmits the output from the speed reducing unit to the left and right wheel drive shafts. Can be configured.

  A motor driving device having a one-motor structure by a motor unit using the motor case of the present invention, a speed reducing unit that decelerates and outputs the rotation of the motor unit, and a differential that transmits the output from the speed reducing unit to the left and right constant velocity joints Can be configured.

  The said reduction part can be comprised by a cycloid reduction gear or a planetary gear reduction gear.

  The motor part can be constituted by a radial gap motor or an axial gap motor.

  You may provide a lubricating oil storage part in the lower part of the housing of the said deceleration part.

  Since the motor case according to the present invention has a structure including a cooling water passage therein, a water cooling type cooling system can be arranged in a space-saving manner and an efficient cooling performance can be obtained.

  Since the motor case according to the present invention can be constituted by two bottomed cylindrical members, it is possible to form a water channel therein by a processing method with little waste such as die casting or casting.

  In the motor case according to the present invention, since the cylindrical member covering the outer periphery of the water channel can be integrated with the case of the motor housing or the rear cover, it is possible to reduce the number of parts and the manufacturing and assembly costs.

It is a schematic sectional drawing of the in-wheel motor drive device which uses the motor case of 1st Embodiment of this invention. It is a schematic sectional drawing which shows the state which isolate | separated the motor case of FIG. It is an expanded sectional view of the III-III line of FIG. It is the figure which looked at the rotary pump of FIG. 1 from the axial direction. It is a schematic sectional drawing of the in-wheel motor drive device which uses the motor case of 2nd Embodiment of this invention. It is a schematic sectional drawing which shows the state which isolate | separated the motor case of FIG. It is a schematic sectional drawing which shows embodiment of the motor drive device of 1 motor structure. It is a rear view of the motor part of embodiment of FIG. It is a schematic sectional drawing which shows the state which isolate | separated the motor case of FIG. It is a schematic sectional drawing of the conventional in-wheel motor drive device.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
1st Embodiment of this invention used for the motor part of an in-wheel motor drive device is described based on FIGS. 1-3.

  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 an output from the deceleration unit B as driving wheels. And a wheel hub bearing portion C for transmitting to the wheel.

  The motor case 22 of the motor part A is provided with a cooling water channel 61 on the outer peripheral part.

  The motor case 22 has a bottomed cylindrical motor housing 22a that opens on the back side for accommodating the stator 23 and the rotor 24, and a cylindrical portion that is fitted from the back side inside the cylindrical portion of the motor housing 22a. And a bottomed cylindrical rear cover 22b.

  A water channel groove 61a is formed on the outer peripheral surface of the cylindrical portion of the rear cover 22b. By fitting the cylindrical portion of the motor housing 22a and the cylindrical portion of the rear cover 22b, a cooling water channel is formed in the water channel groove 61a. 61 is formed.

  The bottom portion of the bottomed cylindrical motor housing 22a functions as a pump housing and forms a lubricating oil passage 22c therein.

  Seal grooves 62a and 62b are provided at positions surrounding the water channel groove 61a formed in the cylindrical portion of the rear cover 22b. When the motor water channel 22a and the rear cover 22b are fitted together to form the cooling water channel 61, the cooling water Prevents leakage.

  The cylindrical portion of the motor housing 22a is provided with a cooling water inlet 63 and a cooling water outlet 64 at positions corresponding to the start and end points of a water channel groove 61a formed on the outer peripheral surface of the rear cover 22b. Cooling water is circulated from the cooling water inlet 63 and the cooling water outlet 64 by a pump provided separately from the drive unit, and the heat generating part (coil) of the motor part A is cooled by this water cooling system.

  Further, the rear cover 22b has a structure in which a lubricating oil passage 22d is formed on the inner side in the circumferential direction of the cooling water passage 61, and the oil circulating through the lubricating oil passage 22d is cooled by the cooling water passage 61.

  Lubricating oil supplied to the speed reduction unit B is supplied from the oil reservoir 22e provided in the lower part of the speed reduction unit B to the lubricating oil flow path 22c, the lubricating oil flow path 22d, and the motor side rotation formed in the pump housing at the bottom of the motor housing 22a. It passes through the hollow path of the member 24b and the hollow path of the speed reducer input shaft 25, is circulated to the speed reduction part B, and the speed reduction part B is cooled.

  The motor part A is fixedly connected to the stator 23 fixed to the cylindrical part of the rear cover 22b, the rotor 24 disposed at a position facing the inner side of the stator 23 with a radial gap therebetween, and the inner side of the rotor 24. This is a radial gap motor including a rotor-side rotation member 24b that rotates integrally with the rotor 24. The motor side rotation member 24b has a hollow path and is rotatably supported with respect to the rear cover 22b by rolling bearings 36a and 36b.

  A reduction gear input shaft 25 having eccentric portions 25a and 25b in the reduction portion B is connected to the motor side rotation member 24b.

  The two eccentric portions 25a and 25b are provided with a 180 ° phase change in order to cancel the centrifugal force due to the eccentric motion.

  The speed reduction part B is held by curved plates 26a and 26b as revolving members that are rotatably held by the eccentric parts 25a and 25b, and an outer pin housing 45 fixed to the housing of the speed reduction part B, and the curved plates 26a and 26b. A plurality of outer pins 27 as outer peripheral engaging members that engage with the outer peripheral portion of the outer peripheral portion, and a motion conversion mechanism that transmits the rotational motion of the curved plates 26 a and 26 b to the wheel-side rotating member 28.

  The wheel side rotation member 28 includes a flange portion 28a and a shaft portion 28b. Holes for fixing the inner pins 31 are formed on the end face of the flange portion 28a at equal intervals on the circumference around the rotation axis of the wheel side rotation member 28. Further, the shaft portion 28b is fitted and fixed to the wheel hub 32 and transmits the output of the speed reducing portion B to the wheel. The flange portion 28a of the wheel side rotation member 28 and the reduction gear input shaft 25 are rotatably supported by a rolling bearing 36c.

  As shown in FIG. 3, the curved plates 26 a and 26 b have a plurality of corrugations composed of trochoidal curves such as epitrochoids on the outer periphery, and a plurality of through holes 30 a penetrating from one end face to the other end face. Have A plurality of through holes 30a are provided at equal intervals on the circumference centering on the rotation axis of the curved plates 26a, 26b, and receive inner pins 31 described later. Further, the through hole 30b is provided at the center of the curved plates 26a and 26b and is fitted to the eccentric portions 25a and 25b.

  The curved plates 26a and 26b are supported by the rolling bearing 41 so as to be rotatable with respect to the eccentric portions 25a and 25b. As shown in FIG. 3, the rolling bearing 41 is fitted to the outer diameter surface of the eccentric portion 25a, and the inner ring member 42 having an inner raceway surface on the outer diameter surface, and the inner diameter surface of the through hole 30b of the curved plate 26a. A cylinder provided with an outer raceway surface formed directly on the inner raceway surface, a plurality of cylindrical rollers 44 disposed between the inner raceway surface and the outer raceway surface, and a cage (not shown) that holds the spacing between adjacent cylindrical rollers 44. It is a roller bearing.

  The outer pins 27 are provided at equal intervals on a circumferential track around the rotation axis of the speed reducer input shaft 25. When the curved plates 26a and 26b revolve, the curved waveform and the outer pin 27 engage with each other to cause the curved plates 26a and 26b to rotate. Further, in order to reduce the frictional resistance with the curved plates 26a, 26b, needle roller bearings 27a are provided at positions where they abut against the outer peripheral surfaces of the curved plates 26a, 26b.

  On the other hand, the through hole 30a is provided at a position corresponding to each of the plurality of inner pins 31, and the inner diameter of the through hole 30a is the outer diameter of the inner pin 31 ("the maximum outer diameter including the needle roller bearing 31a"). The same shall apply hereinafter).

  The speed reduction unit lubrication mechanism supplies lubricating oil to the speed reduction unit B, and includes a lubricating oil passage 25c, a lubricating oil supply port 25d, a lubricating oil discharge port 25e, a lubricating oil storage unit 22e, and a rotary pump 51. And circulating oil passages 22c and 22d.

  The lubricating oil passage 25c extends along the axial direction inside the motor-side rotating member 25. The lubricating oil supply port 25d is provided in the eccentric portions 25a and 25b.

  In addition, a lubricating oil discharge port 25e for discharging the lubricating oil inside the speed reducing portion B is provided at at least one position below the housing 22f that holds the speed reducing portion B. The lubricating oil discharge port 25e is connected to the lower part of the housing 22a that holds the motor part A, and communicates with a lubricating oil storage part 22e provided at the lower part of the housing 22f.

  The lubricating oil reservoir 22e is provided with a pipe for sucking up the lubricating oil. The lubricating oil in the lubricating oil reservoir 22e is sucked up by the rotary pump 51 and forcibly returned to the lubricating oil passage 25c via the circulating oil passage 22c. I am letting.

  Here, as shown in FIG. 4, the rotary pump 51 includes an inner rotor 52 that rotates using the rotation of the wheel-side rotating member 28, an outer rotor 53 that rotates following the rotation of the inner rotor 52, and a pump The cycloid pump includes a chamber 54, a suction port 55 communicating with the pipe, and a discharge port 56 communicating with the circulating oil passage 22c.

  Inner rotor 52 has a tooth profile formed of a cycloid curve on the outer diameter surface. Specifically, the shape of the tooth tip portion 52a is an epicycloid curve, and the shape of the tooth gap portion 52b is a hypocycloid curve. The inner rotor 52 is fitted to the outer diameter surface of the cylindrical portion of the stabilizer and rotates integrally with the inner pin 31 (wheel-side rotating member 28).

  The outer rotor 53 has a tooth profile constituted by a cycloid curve on the inner diameter surface. Specifically, the shape of the tooth tip portion 53a is a hypocycloid curve, and the shape of the tooth gap portion 53b is an epicycloid curve. The outer rotor 53 is rotatably supported by the housing 22a.

  The inner rotor 52 rotates about the rotation center c1. On the other hand, the outer rotor 53 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 52 is n, the number of teeth of the outer rotor 53 is (n + 1). In this embodiment, n = 5.

  A plurality of pump chambers 54 are provided in the space between the inner rotor 52 and the outer rotor 53. When the inner rotor 52 rotates using the rotation of the wheel side rotation member 28, the outer rotor 53 rotates in a driven manner. At this time, since the inner rotor 52 and the outer rotor 53 rotate about different rotation centers c1 and c2, respectively, the volume of the pump chamber 54 changes continuously. As a result, the lubricating oil flowing in from the suction port 55 is pumped from the discharge port 56 to the circulation flow path 22c.

  Next, a second embodiment of the present invention in which the configuration of the motor case 22 is different will be described with reference to FIGS.

  The second embodiment is the same in that the motor case 22 is composed of two members, a bottomed cylindrical motor housing 22a and a rear cover 22b. In this embodiment, however, the cylindrical portion of the motor housing 22a is used. The cylindrical portion of the rear cover 22b is fitted to the outer periphery of the motor, and a water channel groove 61a that forms the cooling water channel 61 is formed on the outer peripheral surface of the cylindrical portion of the motor housing 22a.

  In addition, since the configurations of the motor unit A, the speed reduction unit B, and the wheel hub bearing unit C are basically the same as those of the first embodiment, these configurations are denoted by the same reference numerals and detailed description thereof is omitted. To do.

  Next, FIG. 7 to FIG. 9 show the motor part A using the motor case of the present invention, the speed reduction part B that decelerates and outputs the rotation of the motor part A, the output from the speed reduction part B, right and left, etc. This is an embodiment of a motor driving device having a one-motor structure with a differential D transmitted to the speed joint 71.

  As in the second embodiment, the motor case 22 of this embodiment is configured by two members, a bottomed cylindrical motor housing 22a and a rear cover 22b, and the rear cover 22b is arranged on the outer periphery of the cylindrical portion of the motor housing 22a. The water channel groove 61a that forms the cooling water channel 61 is formed on the outer peripheral surface of the cylindrical portion of the motor housing 22a.

  Seal grooves 62a and 62b are provided at positions surrounding the water channel groove 61a of the motor housing 22a. When the cooling water channel 61 is formed by fitting the motor housing 22a and the rear cover 22b, leakage of the cooling water is prevented.

  The water channel groove 61a formed on the outer peripheral surface of the cylindrical portion of the motor housing 22a is a spiral groove as shown in FIG. 9, and at the start and end points of the spiral groove, as shown in FIG. A cooling water inlet 63 and a cooling water outlet 64 are provided, and the cooling water is circulated by a pump provided separately from the drive unit.

  With this water cooling system, the heat generating part (coil) of the motor part A is cooled.

  In the embodiment of the motor driving device having one motor structure, as in the first embodiment, a water channel groove 61a is formed on the outer peripheral surface of the cylindrical portion of the rear cover 22b, and the cylindrical portion of the motor housing 22a, By fitting the cylindrical portion of the rear cover 22b, the cooling water channel 61 can be formed in the water channel groove 61a.

  In the above embodiment, the bottomed cylindrical motor housing 22a and the bottomed cylindrical rear cover 22b constituting the motor case 22 can be manufactured by die casting or casting.

Further, the cooling water channel 61 provided in the motor case 22 may have any shape as long as it can circulate from the cooling water inlet 63 toward the cooling water outlet 64 such as a C-shaped cross section and an O-shaped cross section in addition to a spiral shape. Any shape may be used.
Moreover, in the above embodiment, the water channel 61 for cooling is formed by fitting the water channel groove carved in one outer peripheral surface of the two bottomed cylindrical members and the inner diameter of the other cylindrical portion. However, the water channel may be formed by fitting the water channel groove carved on the inner peripheral surface of one cylindrical portion and the outer diameter of the other cylindrical portion.

  In the present specification, “electric vehicle” is a concept including all vehicles that obtain driving force from electric power, and should be understood as including, for example, a hybrid vehicle.

  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.

21 In-wheel motor drive device 22 Motor case 22a Motor housing 22b Rear cover 22c, 22d Lubricating oil flow path 23 Stator 24 Rotor 24b Motor side rotation member 25 Reduction gear input shaft 51 Rotary pump 61 Cooling water channel 61a Water channel grooves 62a, 62b Seal groove 63 Cooling water inlet 64 Cooling water outlet 71 Constant velocity joint A Motor part B Deceleration part C Wheel hub bearing part D Differential

Claims (12)

  A bottomed cylindrical motor housing that opens on the back side that accommodates the stator and the rotor, and a bottomed cylindrical rear cover that is integrally formed with a cylindrical portion that fits from the back side inside the cylindrical portion of the motor housing; A motor case comprising a cooling water channel on the outer peripheral portion, wherein a water channel groove is formed on the outer peripheral surface of the cylindrical portion of the rear cover.   A bottomed cylindrical motor housing that opens on the back side that accommodates the stator and rotor, and a bottomed cylindrical rear cover that is integrally formed with a cylindrical portion that fits from the back side outside the cylindrical portion of the motor housing. A motor case having a cooling water channel on the outer peripheral portion, wherein a water channel groove is formed on the outer peripheral surface of the cylindrical portion of the motor housing.   3. The motor case according to claim 1, wherein an oil passage for lubricating oil is formed in the bottomed cylindrical motor housing and the rear cover.   The motor case according to any one of claims 1 to 3, wherein the bottomed cylindrical motor housing and the rear cover are formed by die casting or casting.   A motor section using the motor case according to any one of claims 1 to 4, a speed reduction section that decelerates and outputs rotation of the motor section, and a wheel hub bearing section that transmits output from the speed reduction section to the drive wheels. An in-wheel motor drive device provided.   A motor unit using the motor case according to any one of claims 1 to 4, a decelerating unit that decelerates and outputs the rotation of the motor unit, and outputs from the decelerating unit via left and right wheel drive shafts The motor drive device of 1 motor structure which tells to.   A motor unit using the motor case according to any one of claims 1 to 4, a deceleration unit that decelerates and outputs the rotation of the motor unit, and outputs from the deceleration unit to the left and right constant velocity joints via a differential The motor drive device of 1 motor structure which tells to.   The motor drive device according to any one of claims 5 to 7, wherein the speed reduction unit is configured by a cycloid speed reducer.   The motor drive device according to any one of claims 5 to 7, wherein the speed reduction portion is constituted by a planetary gear speed reducer.   The motor driving apparatus according to claim 5, wherein the motor unit is a radial gap motor.   The motor driving apparatus according to claim 5, wherein the motor unit is an axial gap motor. The motor drive device according to any one of claims 5 to 11, wherein the lubricating oil storage part is provided in a lower part of the housing of the speed reduction part.

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