JP2013104532A - In-wheel motor vehicle driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-wheel motor vehicle driving device capable of preventing lubricating oil from leaking in the in-wheel motor vehicle driving device including a lubricating oil supply mechanism.SOLUTION: The in-wheel motor vehicle driving device including a motor 1 that drives wheels, a reduction gear 2 that decelerates the rotation of the motor 1, a bearing 5 for the wheels that are rotated by an input axis 3 of the reduction gear 2 and a coaxial output member 4, and the lubricating oil supply mechanism 40 that supplies the lubricating oil used for either of the lubrication of the reduction gear 2 and cooling of the motor 1 or both of them. The lubricating oil supply mechanism 40 has a lubricating oil storage section 45 that stores the lubricating oil. A lead-out section 21 of a motor cable 20 that is led out outward from the motor 1 is provided above the level H1 of the lubricating oil stored in the lubricating oil storage section 45 with the motor 1 suspended.

Description

  The present invention relates to an in-wheel motor vehicle drive device used for drive wheels of, for example, an electric vehicle.

  An in-wheel motor drive device having a wheel bearing, a motor, and a reduction gear interposed between the motor and the wheel bearing has been proposed (Patent Document 1). Since the in-wheel motor drive device is disposed around the undercarriage of the vehicle, a power cable that electrically connects the in-wheel motor drive device and a drive source that drives the drive device is required. The power cable is fastened by screws, soldering, caulking or the like in order to connect to the motor coil. Further, the in-wheel motor drive device is disposed around the suspension as described above, and it is necessary to reduce the dimension in the axial direction in order to ensure a wide interior space. FIG. 8A is a front view of a conventional in-wheel motor drive device, and FIG. 8B is a side view of the in-wheel motor drive device viewed from the axial direction. In order to reduce the axial dimension of the in-wheel motor drive device, a structure has been proposed in which the terminal box 101 of the power cable 100 is disposed on the side surface of the motor housing 102a of the motor 102, as shown in FIG.

JP 2009-219271 A

  The conventional structure shown in FIG. 8 is provided with a lubricating oil supply mechanism (not shown) that supplies lubricating oil used for lubricating the speed reducer 103 and cooling the motor 102. In this case, there is a possibility that the lubricating oil stored in the motor housing 102a leaks out from the lead-out portion 104 of the power cable 100 through the power cable 100 to the outside.

  An object of the present invention is to provide an in-wheel motor vehicle drive device capable of preventing leakage of lubricant oil in an in-wheel motor vehicle drive device including a lubricant oil supply mechanism.

The in-wheel motor vehicle drive device of the present invention includes a motor for driving a wheel, a speed reducer for reducing the rotation of the motor, a wheel bearing rotated by an output member coaxial with an input shaft of the speed reducer, In an in-wheel motor vehicle drive device provided with a lubricating oil supply mechanism that supplies lubricating oil used for either or both of reduction gear lubrication and motor cooling,
The lubricating oil supply mechanism has a lubricating oil storage part for storing lubricating oil, and the lubricating oil stored in the lubricating oil storage part when the motor is stopped is used as the motor cable lead-out part drawn out from the motor. It is characterized by being provided above the oil level height.

  According to this configuration, the motor cable lead-out portion is provided above the oil surface height of the lubricating oil stored in the lubricating oil storage portion when the motor is stopped, so that the lubricating oil stored in the lubricating oil storage portion is There is no risk of leaking out of the motor cable through the motor cable. Thus, since leakage of lubricating oil can be prevented, reduction gear lubrication and motor cooling can be performed reliably. As a result, the motor can be rotated at a high speed and, for example, maintenance such as confirmation of the oil level of the lubricating oil reservoir can be facilitated.

  The lubricating oil supply mechanism includes a lubricating oil passage provided in a motor housing of a motor, a motor rotating shaft oil passage provided along an axial center in a motor rotating shaft of the motor, and communicating with the lubricating oil passage; A reduction gear oil passage that is provided in the reduction gear and communicates with the lubricating oil flow path and the lubricating oil storage section to supply the lubricating oil to the reduction gear, and sucks up the lubricating oil stored in the lubricating oil storage section to An axial oil supply mechanism having a reduction gear oil passage and a pump circulating through the motor rotation shaft oil passage may be used. In this case, since the motor can be cooled by circulating the lubricating oil by the pump, for example, it is not necessary to provide another coolant passage in the motor housing. Further, since the lubricating oil can be circulated by effectively using the space in the motor rotation shaft, the lubricating oil can be supplied to a necessary place without newly providing a piping for the lubricating oil. For this reason, the number of parts can be reduced, and the overall size of the in-wheel motor vehicle drive device can be reduced.

  The oil level height of the lubricating oil stored in the lubricating oil storage section when the motor is stopped may be set to a level that is applied to the motor rotor of the motor. In this case, the motor rotor can be cooled, and the stirring resistance of the lubricating oil can be reduced as compared with the case where the entire motor rotor is immersed in the lubricating oil, for example. Thereby, the efficiency of power transmission can be improved.

An angle sensor for detecting a rotation angle of the motor may be provided, and the motor cable may include a power cable for supplying electric power for rotationally driving the motor and a rotation angle detection cable for the angle sensor.
Coil temperature detection means for detecting the temperature of the coil of the motor may be provided, and the motor cable may include a cable for coil temperature detection means.
Rotor temperature detection means for detecting the temperature of the motor rotor of the motor may be provided, and the motor cable may include a cable for rotor temperature detection means.

The motor may be provided with sealing means for sealing the lead-out portion of the motor cable. In this case, it is possible to more reliably prevent the lubricating oil from leaking out of the motor cable drawer.
The speed reducer may be a cycloid speed reducer.

The in-wheel motor vehicle drive device of the present invention includes a motor for driving a wheel, a speed reducer for reducing the rotation of the motor, a wheel bearing rotated by an output member coaxial with an input shaft of the speed reducer, In an in-wheel motor vehicle drive device provided with a lubricating oil supply mechanism that supplies lubricating oil used for either or both of reduction gear lubrication and motor cooling,
The lubricating oil supply mechanism has a lubricating oil storage part for storing lubricating oil, and the lubricating oil stored in the lubricating oil storage part when the motor is stopped is used as the motor cable lead-out part drawn out from the motor. It was provided above the oil level height. For this reason, in the in-wheel motor vehicle drive device including the lubricating oil supply mechanism, leakage of the lubricating oil can be prevented.

(A) is a front view of the in-wheel motor vehicle drive device according to the first embodiment of the present invention, (B) is a side view of the in-wheel motor vehicle drive device viewed from the axial direction, and (C) is the same. It is a front view of an in-wheel motor vehicle drive device. It is sectional drawing of the same in-wheel motor vehicle drive device. It is sectional drawing of the reduction gear used as the III-III line cross section of FIG. FIG. 4 is a partially broken plan view of the terminal box of the in-wheel motor vehicle drive device (end view taken along line IV-IV in FIG. 2). It is a block diagram of the control system which concerns on other embodiment of this invention. It is a block diagram of a conceptual structure which shows the electric vehicle containing the same in-wheel motor vehicle drive device with a top view. It is a block diagram of the control system of the electric vehicle. (A) is the front view of the in-wheel motor drive device of a prior art example, (B) is the side view which looked at the in-wheel motor drive device from the axial direction.

A first embodiment of the present invention will be described with reference to FIGS.
The in-wheel motor vehicle drive device according to this embodiment is mounted on, for example, an electric vehicle. FIG. 1A is a front view of the in-wheel motor vehicle drive device according to this embodiment (end view taken along line IA-IA in FIG. 1B), and FIG. 1B is the same in-wheel motor vehicle. It is the side view which looked at the drive device from the axial direction. FIG.1 (C) is a front view (IC-IC line end view of FIG.1 (B)) of the in-wheel motor vehicle drive device.
As shown in FIGS. 1A and 1C, an in-wheel motor vehicle drive device includes a motor 1 that drives wheels, a speed reducer 2 that decelerates the rotation of the motor 1, and an input shaft of the speed reducer 2. 3 (FIG. 2) and a wheel bearing 5 rotated by an output member 4 coaxial with the output member 4 and a lubricating oil supply mechanism described later.

  The reduction gear 2 is interposed between the wheel bearing 5 and the motor 1, and the wheel hub, which is a driving wheel supported by the wheel bearing 5, and the motor rotating shaft 6 (FIG. 2) of the motor 1 are coaxial. Connected above. An upper arm 8 a and a lower arm 8 b of the suspension 8 are connected to the speed reducer housing 7 of the speed reducer 2. In this specification, the side closer to the outside in the vehicle width direction of the vehicle with the in-wheel motor vehicle drive device attached to the vehicle is referred to as the outboard side, and the side closer to the center of the vehicle is referred to as the inboard side. Call.

  As shown in FIG. 2, the motor 1 includes a radial gap type IPM motor in which a radial gap is provided between a motor stator 10 fixed to a cylindrical motor housing 9 and a motor rotor 11 attached to the motor rotating shaft 6. That is, an embedded magnet type coaxial motor). The motor housing 9 is provided with bearings 12 and 13 spaced apart in the axial direction, and the motor rotating shaft 6 is rotatably supported by the bearings 12 and 13. The motor rotating shaft 6 transmits the driving force of the motor 1 to the speed reducer 2. A flange portion 6a extending radially outward is provided in the vicinity of the middle portion of the motor rotating shaft 6 in the axial direction, and the motor rotor 11 is attached to the flange portion 6a via a rotor fixing member 14.

  The motor 1 is provided with an angle sensor 15 that detects a relative rotation angle between the motor stator 10 and the motor rotor 11. The angle sensor 15 detects and outputs a signal representing a relative rotation angle between the motor stator 10 and the motor rotor 11, and an angle calculation circuit 17 that calculates an angle from a signal output from the angle sensor body 16. And have. The angle sensor main body 16 includes, for example, a detected portion 16a provided on the outer peripheral surface of the motor rotating shaft 6, and a detecting portion 16b provided in the motor housing 9 and disposed close to the detected portion 16a, for example, in the radial direction. And have. The detected portion 16a and the detecting portion 16b may be arranged close to each other in the axial direction. The angle sensor 15 may be a resolver.

  A terminal box 18 is provided on the upper portion of the motor housing 9. As shown in FIG. 4, a plurality of terminals 19 are provided in the terminal box 18. FIG. 4 is an end view taken along line IV-IV in FIG. A lead-out portion 21 for the motor cable 20 is provided at one end portion 18 a on the inboard side of the terminal box 18. At one end 18 a of the terminal box 18, a sealing means 22 such as a grommet that seals the drawer portion 21 is provided. The sealing means 22 is formed in a cylindrical shape from an elastic body such as rubber, and is provided with flange portions 22a and 22a at both ends in the axial direction. The outer peripheral surface of the sealing means 22 is press-fitted into the drawer portion 21 in the one end portion 18a of the terminal box 18, and the inner and outer surfaces of the one end portion 18a are sandwiched between both flange portions 22a and 22a. The motor cable 20 is passed in close contact with the hollow portion of the sealing means 22. In this example, the motor cable 20 includes a power cable 20a that supplies electric power for rotationally driving the motor 1, and a rotation angle detection cable 20b for the angle sensor 15 that detects the rotation angle of the motor 1 described above. In the motor housing 9 (FIG. 2), the wiring of each phase (U, V, W) in the motor 1 is extended and connected to the corresponding terminals 19 in the terminal box 18, respectively. A power cable 20 a is connected to each terminal 19.

These power cables 20a are drawn out of the motor from the drawer portion 21 of the terminal box 18 and are connected to an inverter described later mounted on the vehicle. The inverter converts the direct current of the battery into three-phase alternating current power used for driving the motor 1.
As shown in FIG. 2, in the motor housing 9, wires extending from the detection portion 16 b in the angle sensor main body 16 are connected to corresponding terminals 19 in the terminal box 18. A rotation angle detection cable 20 b is connected to the terminal 19. The rotation angle detection cable 20b is drawn out of the motor from the lead-out portion 21 of the terminal box 18, and is connected to a motor control portion described later.

  The input shaft 3 of the speed reducer 2 has one axial end extending into the motor rotation shaft 6 and is splined to the motor rotation shaft 6. A bearing 23 is provided in the speed reducer housing 7, and the other axial end of the input shaft 3 is supported by the bearing 23. Therefore, the input shaft 3 and the motor rotating shaft 6 of the speed reducer 2 are supported by the bearings 12, 13, and 23 so as to be rotatable together. Eccentric portions 24 and 25 are provided on the outer peripheral surface of the reduction gear housing 7 near the other axial end of the input shaft 3. These eccentric portions 24 and 25 are provided with a 180 ° phase shift so that the centrifugal force due to the eccentric motion is canceled out from each other.

  The speed reducer 2 may have a reduction ratio of 1/6 or more. The speed reducer 2 is a cycloid speed reducer having curved plates 26 and 27, a plurality of outer pins 28, a motion conversion mechanism 29, and counterweights 30 and 30. As shown in FIG. 3, the curved plates 26 and 27 are rotatably provided in the eccentric portions 24 and 25, respectively. A plurality of outer pins 28 are supported across the motor housing 9 and the speed reducer housing 7, and these outer pins 28 are in rolling contact with the outer peripheries of the curved plates 26 and 27. The motion conversion mechanism 29 is a mechanism for transmitting the rotational motion of the curved plates 26 and 27 to the output member 4. The motion conversion mechanism 29 includes a plurality of inner pins 31 provided in the output member 4 and through holes 32 provided in the curved plates 26 and 27. The inner pins 31 are arranged at equal intervals in the circumferential direction around the rotation axis of the output member 4. As shown in FIG. 2, counterweights 30 and 30 are provided at axial positions adjacent to the eccentric portions 24 and 25 in the input shaft 3 of the speed reducer 2, respectively.

  The wheel bearing 5 includes an outer member 33 having a double-row raceway surface formed on the inner periphery, an inner member 34 having a raceway surface facing the respective raceway surfaces on the outer periphery, the outer member 33 and the inner member. And the double row rolling elements 35 interposed between the raceway surfaces of the side members 34. The inner member 34 also serves as a hub for mounting the drive wheel. The wheel bearing 5 is a double-row angular ball bearing, and the rolling elements 35 are formed of balls and are held by a cage for each row. The raceway surface has an arc shape in cross section, and each raceway surface is formed such that the contact angle is aligned with the back surface. Further, the outboard side end and the inboard side end of the bearing space between the outer member 33 and the inner member 34 are sealed by seal members 36 and 37, respectively.

  The outer member 33 is a stationary raceway, and has a flange 33a attached to the outboard side end of the speed reducer housing 7. The outer member 33 and the speed reducer housing 7 are an integral part. . The flange 33a is provided with bolt insertion holes at a plurality of locations in the circumferential direction, and the speed reducer housing 7 is provided with bolt screw holes made of female screws at positions corresponding to the bolt insertion holes. The outer member 33 is attached to the speed reducer housing 7 by screwing the mounting bolt inserted through the bolt insertion hole into the bolt screwing hole.

  The inner member 34 is a rotation side raceway, and a step portion 34a is formed on the outer peripheral surface on the inboard side in the hollow portion through which the output member 4 is inserted, and the inner ring 38 is fitted to the step portion 34a. It is fixed. A row of raceway surfaces is integrally formed on the outer peripheral surface of the inner member 34, and another row of raceway surfaces is formed on the outer peripheral surface of the inner ring 38. A hub flange 34 a for attaching a wheel is provided at the end of the inner member 34 on the outboard side. A spline hole is formed in the hollow portion of the inner member 34, and the output member 4 is spline fitted into the hollow portion. A male screw is formed at the distal end portion of the output member 4, and the output member 4 and the inner member 34 are connected by screwing a nut 39 to the distal end portion of the output member 4 protruding from the hollow portion.

The lubricating oil supply mechanism 40 will be described.
In this example, the lubricating oil supply mechanism 40 is a mechanism that supplies lubricating oil used for both the lubrication of the speed reducer 2 and the cooling of the motor 1. The lubricating oil supply mechanism 40 is a so-called shaft-centered oil supply mechanism, and includes a lubricating oil passage 41, a motor rotation shaft oil passage 42, a speed reducer oil passage 43, a pump 44, and a lubricating oil reservoir that stores the lubricating oil. Part 45. The lubricating oil passage 41 is provided in the motor housing 9 and includes a first passage 41a to a fourth passage 41d. The first flow path 41a extends in an inclined manner from the lubricating oil reservoir 45 to the suction port 44a of the pump 44, and the second flow path 41b extending in the radial direction and the third direction extending in the axial direction sequentially to the discharge port 44b of the pump 44. The flow path 41c communicates with the fourth flow path 41d extending mainly in the radial direction. A reduction gear oil passage 43 is connected to the middle of the second passage 41b. The lubricating oil stored in the lubricating oil storage part 45 is sucked up by the pump 44 and guided to the lubricating oil passage 41 and the speed reducer oil passage 43.

  The motor rotation shaft oil passage 42 is provided along the shaft center in the motor rotation shaft 6 and communicates with the fourth flow passage 41 d of the lubricating oil passage 41. In the motor rotating shaft 6, a plurality of through holes 6b penetrating in the radial direction are provided at axial positions where the rotor fixing member 14 is provided. The rotor fixing member 14 is provided with an oil passage 14a that communicates with the plurality of through holes 6b and extends radially outward. The oil passage 14 a communicates with an annular gap δ 1 between the rotor fixing member 14 and the inner peripheral surface of the motor rotor 11. The lubricating oil is sequentially led to the annular gap δ1 via the lubricating oil passage 41, the motor rotation shaft oil passage 42, the through hole 6b, and the oil passage 14a, and is used for cooling the motor 1. The lubricating oil used for cooling is discharged from the slit between the flange 14 b of the rotor fixing member 14 and the end surface of the motor rotor 11, and stored in the lubricating oil reservoir 45.

The speed reducer oil passage 43 is provided in the speed reducer 2 and communicates with the lubricating oil flow path 41 and the lubricating oil reservoir 45 to supply the lubricating oil to the speed reducer 2. The lubricating oil that lubricates the inside of the speed reducer moves radially outward and downward due to centrifugal force and gravity, and is returned to the lubricating oil reservoir 45.
The pump 44 is provided in the middle of the flow path between the first flow path 41a and the second flow path 41b in the lubricating oil flow path 41, and forcibly circulates the lubricating oil. The pump 44 includes, for example, an inner rotor (not shown) that rotates as the output member 4 rotates, an outer rotor that rotates following the rotation of the inner rotor, a pump chamber, the suction port 44a, and the discharge port. 44b. When the inner rotor is rotated by the rotation of the inner member 34, the outer rotor is driven to rotate. At this time, the inner rotor and the outer rotor rotate about different rotation centers, so that the volume of the pump chamber changes continuously. As a result, the lubricating oil flowing in from the suction port 44a is pumped from the discharge port 44b to the second flow path 41b.

  The lubricating oil reservoir 45 includes a speed reducer side reservoir 45a and a motor side reservoir 45b. The reduction gear side storage portion 45 a is provided in the lower portion of the reduction gear housing 7, and the motor side storage portion 45 b is provided in the lower portion of the motor housing 9. A through hole 46 is formed in the lower part of the motor housing 9 at one axial end where the first flow path 41a is formed. The speed reducer side reservoir 45a and the motor side reservoir 45b communicate with each other through the through hole 46 to have the same oil level height H1. In the speed reducer 2, the lubricating oil that lubricates the inside of the speed reducer moves downward by centrifugal force and gravity and is stored in the speed reducer-side storage portion 45 a. In the motor 1, the lubricating oil used for cooling the motor 1 moves downward due to centrifugal force and gravity and is stored in the motor-side storage portion 45 b.

  The lead-out part 21 of the motor cable 20 in the terminal box 18 is provided above the oil level height H1 of the lubricating oil stored in the lubricating oil storage part 45. The oil level height H1 refers to the oil level height of the lubricating oil stored in the lubricating oil storage unit 45 when the motor 1 is stopped. The oil level height H1 of the lubricating oil stored in the lubricating oil storage unit 45 is such that it is applied to the motor rotor 11 when the motor 1 is stopped, specifically, the outer peripheral surface of the motor rotor 11 is immersed in the lubricating oil. It has been established.

  As oil level confirmation means for confirming the oil level H1 of the lubricating oil, for example, an insertion hole into which the level gauge can be inserted and removed is provided in the motor housing 9, and the position (level) of the lubricating oil that adheres to the level gauge Thus, the oil level height H1 may be visually confirmed, or a light transmissive window for oil level height confirmation may be provided in the motor housing 9, and the oil level height H1 may be visually confirmed from this window. A liquid level sensor for detecting the oil level H1 may be provided in the motor housing 9 in place of the oil level check means or together with the oil level check means. The liquid level sensor comprises a magnetic, optical, electrode or ultrasonic liquid level sensor used for liquid level control. In this case, determination means for determining whether or not the value detected by the liquid level sensor is within the upper limit value and lower limit value of the oil level height H1 is provided in a motor control unit described later. It is done.

The effect will be described.
Since the drawer portion 21 of the motor cable 20 is provided above the oil level height H1 of the lubricating oil stored in the lubricating oil storage portion 45 when the motor 1 is stopped, the lubricating oil stored in the lubricating oil storage portion 45 is provided. There is no possibility of oil leaking from the lead-out portion 21 of the motor cable 20 to the outside through the motor cable 20. Thus, since the leakage of the lubricating oil can be prevented, the reduction gear 2 can be lubricated and the motor 1 can be reliably cooled. Thereby, the high speed rotation of the motor 1 can be achieved. Furthermore, it is possible to reduce the frequency of visually checking the oil level height H1 of the lubricating oil reservoir 45 by the oil level height checking unit. For this reason, the maintenance of the in-wheel motor vehicle drive device can be facilitated.

  Since the motor 1 can be cooled by circulating the lubricating oil by the pump 44, for example, it is not necessary to provide another coolant passage in the motor housing 9. The motor stator 10 is cooled by the lubricating oil flowing in the third flow path 41 c of the lubricating oil flow path 41 provided in the motor housing 9 and the lubricating oil stored in the motor side storage section 45 b of the lubricating oil storage section 45. Is done. Moreover, most of the surface area of the motor rotor 11 is cooled by the lubricating oil being guided to the annular gap δ1 and discharged from the slit. Thus, the motor 1 can be cooled effectively by cooling the motor stator 10 and the motor rotor 11 respectively. In addition, since the lubricating oil can be circulated by effectively using the space in the motor rotating shaft 6, the lubricating oil can be supplied to a necessary place without newly providing a piping for the lubricating oil. For this reason, the number of parts can be reduced, and the overall size of the in-wheel motor vehicle drive device can be reduced.

Since the oil level height H1 of the lubricating oil stored in the lubricating oil storage unit 45 in the driving stop state of the motor 1 is set to the extent that it is applied to the motor rotor 11 of the motor 1, the lubricating oil stored in the lubricating oil storage unit 45 is also used. The motor rotor 11 can be cooled. At the same time, for example, the stirring resistance of the lubricating oil can be reduced as compared with the case where the entire motor rotor is immersed in the lubricating oil. Thereby, the efficiency of power transmission can be improved.
Since the terminal box 18 is provided with the sealing means 22 for sealing the lead-out portion 21, it is possible to more reliably prevent the lubricating oil from leaking outside from the lead-out portion 21 of the motor cable 20.
When the reduction gear 2 in the in-wheel motor vehicle drive device is a cycloid reduction gear and the reduction ratio is increased to, for example, 1/6 or more, the motor 1 can be downsized and the device can be downsized. As described above, the lead-out portion 21 of the motor cable 20 is provided above the oil level height H1 of the lubricating oil stored in the lubricating oil storage portion 45 when the driving of the motor 1 is stopped, and the reduction ratio is increased. As a result, the motor 1 can be rotated at a high speed.

Another embodiment will be described.
As shown in FIG. 5, the coil temperature detecting means Sa for detecting the temperature of the coil 1a of the motor 1 is provided, and the motor cable 20 (FIG. 2) may include a cable for the coil temperature detecting means. . In this case, for example, a thermistor is used as the coil temperature detecting means Sa. The temperature of the coil 1a can be detected by fixing the thermistor in contact with the coil 1a. The detection value detected by the coil temperature detection means Sa is amplified by the amplifier Ap in the motor control unit, and this amplification value is determined by the determination unit 47. The determination unit 47 always determines whether or not the temperature detected by the coil temperature detection means Sa exceeds a predetermined threshold value. The threshold value is appropriately obtained based on the relationship between the temperature and time of the coil 1a that causes the coil 1a to be insulated, for example, through experiments and simulations. When such a coil temperature detecting means Sa is provided, abnormalities such as insulation deterioration of the motor coil 1a can be detected at an early stage during high-speed operation, and appropriate measures can be quickly taken.
Rotor temperature detection means for detecting the temperature of the motor rotor 11 may be provided, and the motor cable 20 may include a cable for rotor temperature detection means. A thermistor or the like is also used as the rotor temperature detecting means.

  FIG. 6 is a block diagram of a conceptual configuration showing an electric vehicle including the in-wheel motor vehicle drive device according to any of the embodiments in a plan view. This electric vehicle is a four-wheeled vehicle in which the wheels 52 that are the left and right rear wheels of the vehicle body 51 are driving wheels and the wheels 53 that are the left and right front wheels are steering wheels of driven wheels. Each of the wheels 52 and 53 serving as the driving wheel and the driven wheel has a tire and is supported by the vehicle body 51 via the wheel bearing 5. In FIG. 6, the wheel bearing 5 is abbreviated as “H / B” as a hub bearing. The left and right wheels 52, 52 serving as driving wheels are driven by independent traveling motors 1, 1, respectively. The rotation of the motor 1 is transmitted to the wheel 52 via the speed reducer 2 and the wheel bearing 5. The motor 1, the speed reducer 2, and the wheel bearing 5 constitute an in-wheel motor vehicle drive device 58 that is one assembly part, and the in-wheel motor vehicle drive device 58 is partially or entirely a wheel. 52. The wheels 52 and 53 are provided with electric brakes 59 and 60, respectively.

  The wheels 53, 53, which are steering wheels serving as left and right front wheels, can be steered via a steering mechanism 61 and are steered by a steering mechanism 62. The steering mechanism 61 is a mechanism that changes the angle of the left and right knuckle arms 11b that hold the wheel bearings 5 by moving the tie rod 61a left and right. The EPS (electric power steering) motor 63 converts rotation and linear motion. It can be moved left and right via a mechanism (not shown). The steering mechanism 62 detects a steering angle of a steering wheel 64 that is not mechanically connected to the tie rod 61a by a steering angle sensor 65, and supplies a drive command to the EPS motor 63 by a turning command that is the detected steering angle. It is an expression.

The control system will be described.
The vehicle body 51 includes an ECU 71 that is an electric control unit that controls the entire automobile, an inverter device 72 that controls the traveling motor 1 in accordance with a command from the ECU 71, and a brake controller 73. The ECU 71 includes a computer, a program executed on the computer, various electronic circuits, and the like.

  The ECU 71 is roughly divided into a drive control unit 71a and a general control unit 71b when classified roughly by function. The drive control unit 71a gives the left and right wheel travel motors 1 and 1 the acceleration command output from the accelerator operation unit 66, the deceleration command output from the brake operation unit 67, and the turn command output from the steering angle sensor 65. The given acceleration / deceleration command is generated and output to the inverter device 72. In addition to the above, the drive control unit 71a outputs the acceleration / deceleration command to be output, information on the tire rotation speed obtained from the rotation sensor 74 provided on the wheel bearings 5 and 5 for the wheels 52 and 53, You may have the function to correct | amend using the information of each sensor. The accelerator operation unit 66 includes an accelerator pedal and a sensor 66a that detects the amount of depression and outputs the acceleration command. The brake operation unit 67 includes a brake pedal and a sensor 67a that detects the amount of depression and outputs the deceleration command.

  The general control unit 71b of the ECU 71 processes a function of outputting a deceleration command output from the brake operation unit 67 to the brake controller 73, a function of controlling various auxiliary machine systems 75, and an input command from the console operation panel 76. A function, a function of displaying on the display device 77, and the like. The display device 77 can display an image of a liquid crystal display device or the like. The auxiliary machine system 75 is, for example, an air conditioner, a light, a wiper, a GPS, an air bag, etc., and is shown here as a representative block.

  The brake controller 73 is means for giving a braking command to the brakes 59 and 60 of the wheels 52 and 53 in accordance with the deceleration command output from the ECU 71. The braking command output from the ECU 71 includes a command generated by means for improving the safety of the ECU 71 in addition to the command generated by the deceleration command output from the brake operation unit 67. In addition, the brake controller 73 includes an antilock brake system. The brake controller 73 is configured by an electronic circuit, a microcomputer, or the like.

  The inverter device 72 includes a power circuit unit 78 provided for each motor 1 and a motor control unit 79 that controls the power circuit unit 78. The motor control unit 79 may be provided in common for each power circuit unit 78 or may be provided separately, but even if it is provided in common, each power circuit unit 78. For example, can be controlled independently so that the motor torque is different from each other. The motor control unit 79 has a function of outputting information (referred to as “IWM system information”) such as detection values and control values related to the in-wheel motor drive device 58 included in the motor control unit 79 to the ECU.

  FIG. 7 is a block diagram of a conceptual configuration in which the inverter device 72 is provided with a determination unit 47A for determining whether the oil level height is within a predetermined value. The power circuit unit 78 includes an inverter 81 that converts DC power of the battery 69 into three-phase AC power used for driving the motor 1, and a PWM driver 82 that controls the inverter 81. The motor 1 is composed of a three-phase synchronous motor or the like. The inverter 81 includes a plurality of semiconductor switching elements (not shown), and the PWM driver 82 performs pulse width modulation on the input current command and gives an on / off command to each of the semiconductor switching elements.

  The motor control unit 79 includes a computer, a program executed on the computer, and an electronic circuit, and includes a motor drive control unit 83 as a basic control unit. The motor drive control unit 83 is a unit that converts the current command into a current command in accordance with an acceleration / deceleration command by a torque command or the like given from the ECU 71 that is a host control unit, and gives the current command to the PWM driver 82 of the power circuit unit 78. The motor drive control unit 83 obtains a motor current value flowing from the inverter 81 to the motor 1 from the current sensor 85 and performs current feedback control. Further, the motor drive control unit 83 obtains the rotation angle of the motor rotor 11 (FIG. 2) from the angle sensor 15 and performs vector control.

  In this embodiment, a liquid level sensor Sb for detecting the oil level is provided in the motor housing, and an upper limit value and a lower limit value of the oil level height H1 for which the value detected by the liquid level sensor Sb is determined. 47A is provided in the motor control unit 79 having the above-described configuration in the inverter device 72. When the determination unit 47A determines that the detected value does not fall between the upper limit value and the lower limit value of the oil level height H1, the determination unit 47A outputs the abnormality value to the abnormality report unit 91. At this time, the abnormality report means 91 reports an abnormality to the ECU 71, and the abnormality display means 92 of the ECU 71 displays an abnormality on the display device 77 in the driver's seat according to the abnormality report. Therefore, the driver can immediately recognize the abnormality, and can take appropriate measures more quickly by the driver, such as stopping or slowing down the vehicle or traveling to a repair shop.

DESCRIPTION OF SYMBOLS 1 ... Motor 2 ... Reduction gear 3 ... Input shaft 4 ... Output member 5 ... Wheel bearing 6 ... Motor rotating shaft 9 ... Motor housing 20 ... Motor cable 21 ... Pull-out part 40 ... Lubricating oil supply mechanism 45 ... Lubricating oil storage part 52 …Wheel

Claims (8)

A motor that drives the wheels;
A speed reducer that decelerates the rotation of the motor;
A wheel bearing rotated by an output member coaxial with the input shaft of the speed reducer;
A lubricating oil supply mechanism that supplies lubricating oil used for either or both of lubrication of the reduction gear and cooling of the motor;
In-wheel motor vehicle drive device comprising:
The lubricating oil supply mechanism has a lubricating oil storage part for storing lubricating oil, and the lubricating oil stored in the lubricating oil storage part when the motor is stopped is used as the motor cable lead-out part drawn out from the motor. An in-wheel motor vehicle drive device characterized by being provided above the oil level. In claim 1, the lubricating oil supply mechanism,
A lubricating oil passage provided in the motor housing of the motor;
A motor rotation shaft oil passage provided along an axis in the motor rotation shaft of the motor and communicating with the lubricating oil passage;
A speed reducer oil path provided in the speed reducer and communicating with the lubricating oil flow path and the lubricating oil reservoir and supplying the lubricating oil to the speed reducer;
A pump that sucks up the lubricating oil stored in the lubricating oil reservoir and circulates it through the lubricating oil passage to the speed reducer oil passage and the motor rotation shaft oil passage;
An in-wheel motor vehicle drive device which is an axial oil supply mechanism having   The in-wheel motor vehicle drive device according to claim 1 or 2, wherein the oil level of the lubricating oil stored in the lubricating oil storage portion when the motor is stopped is applied to a degree that is applied to the motor rotor of the motor.   4. The angle sensor according to claim 1, wherein an angle sensor that detects a rotation angle of the motor is provided, and the motor cable includes a power cable that supplies electric power for rotating the motor, and rotation for the angle sensor. An in-wheel motor vehicle drive device including an angle detection cable.   5. The in-wheel motor vehicle drive device according to claim 1, further comprising a coil temperature detection unit that detects a temperature of the coil of the motor, wherein the motor cable includes a cable for the coil temperature detection unit. .   6. The in-wheel motor vehicle drive device according to claim 1, wherein rotor temperature detection means for detecting a temperature of a motor rotor of the motor is provided, and the motor cable includes a cable for rotor temperature detection means. .   The in-wheel motor vehicle drive device according to any one of claims 1 to 6, wherein the motor is provided with a sealing means for sealing a lead-out portion of the motor cable.   The in-wheel motor vehicle drive device according to any one of claims 1 to 7, wherein the speed reducer is a cycloid speed reducer.

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