JP2000046157A - Vehicular motor driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lubricate a shift gearing desirably and reduce changes in the driving characteristics of a motor. SOLUTION: This motor driver comprises a driver case 11, a stator 25 anchored to the driver case 11, a rotor 27 disposed rotatably diametrally inside the stator 25, a shift gearing disposed diametrally inside the rotor 27 to effect shift on rotation of the rotor 27, an oil passage opening onto the shift gearing, and a guide member formed on the internal wall of the driver case 11 to guide oil raked up by rotation of the rotor 27 into the oil passage. When the rotor 27 is revolved to drive a motor 24, oil within the drive case 11 is raked up and is then guided by the guide member into the oil passage, which feeds it to the shift gearing for lubrication. The shift gearing is thus fed with sufficient oil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor drive device for a vehicle.

[0002]

2. Description of the Related Art Conventionally, an electric vehicle is provided with a motor drive device for a vehicle, and the motor is driven by supplying a current to the motor from a battery mounted on the vehicle. Among them, a wheel motor type electric vehicle is provided with a motor for each wheel, and is run by transmitting rotation generated by each motor to driving wheels.

For this purpose, an input side of a transmission gear unit is connected to an output shaft of a motor, an output rotation shaft is connected to an output side of the transmission gear unit, and a wheel disk is attached to the output rotation shaft. Then, the rotation generated by the motor is shifted by the transmission gear device and transmitted to the wheel disk. By the way, the stator coil generates heat as the motor is driven. Further, frictional heat is generated as the transmission gear device is operated. Therefore, an oil pump is provided to cool the stator coil, the transmission gear, and the like. Further, oil is supplied into the drive device case from above the drive device case surrounding the motor, and the oil cools the stator coil and lubricates the transmission gear device. Further, an oil sump is formed at a lower portion in the drive device case, and the oil accumulated in the oil sump is scraped up by a rotor of a motor and supplied to a predetermined location. It is supposed to.

[0004]

However, in the conventional vehicle motor drive device, when an oil pump is provided, a space for the oil pump is required.
However, especially in a wheel motor type electric vehicle, it is difficult to secure a space for the oil pump in the drive device case. In addition, if oil is stored in the lower part in the drive device case, the scooped oil cannot be efficiently supplied to the transmission gear device.
The transmission gear unit cannot be lubricated well.

A Hall element is provided in the drive device case to detect the number of rotations of the rotor. If the scraped oil adheres to the Hall element, the temperature of the Hall element changes. Resulting in. As a result, the operating magnetic flux density of the Hall element changes, so that the driving characteristics of the motor change. SUMMARY OF THE INVENTION The present invention solves the problems of the above-described conventional vehicle motor drive device, can lubricate the transmission gear device satisfactorily, and can suppress a change in the drive characteristics of the motor. It is intended to provide a device.

[0006]

In order to achieve the above object, in a motor drive device for a vehicle according to the present invention, a drive device case, a stator fixed to the drive device case, and a rotatable inner radial portion of the stator are provided. A rotor disposed, a transmission gear device disposed radially inward of the rotor, and performing a speed change by receiving rotation of the rotor; an oil passage formed facing the transmission gear device; A guide member formed on an inner wall of the device case and guiding the oil scooped up with the rotation of the rotor to the oil passage.

[0007] In another vehicle motor drive device of the present invention, the guide member is formed integrally with the drive device case, extends in the vertical direction, and regulates the circumferential movement of the scraped-up oil. A first rib that extends substantially horizontally and a second rib that restricts the vertical movement of the scooped oil. In still another motor drive device for a vehicle according to the present invention, the oil passage further includes a first oil passage that is opened immediately above the second rib, and a second oil passage that extends radially inside the drive device case. An oil passage, a third oil passage extending in the rotor shaft in the axial direction, and a fourth oil passage extending in the rotor shaft in the radial direction.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a vehicle motor drive device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a drive device case according to the embodiment of the present invention. In the figure, a drive device case 11 has a two-part structure including two dish-shaped first and second casings 12 and 13 disposed inside and outside a vehicle.
By connecting the second casings 12 and 13 with bolts (not shown), the first and second casings 1 and 2 are connected.
Motor chamber 1 having a substantially circular cross section between 2 and 13
5 are formed. The drive device case 11 is attached to a vehicle chassis via a wishbone type suspension device (not shown).

At the center of the second casing 13,
An opening is formed, and the sleeve portion 39a of the wheel hub 39 is inserted into the opening. The wheel hub 39 is rotatably supported by the bearing 40 with respect to the second casing 13. An output shaft 38 is provided in the sleeve portion 39a, and the sleeve portion 39a and the output shaft 38 are spline-engaged. A flange 38a is integrally formed at an outer end of the output shaft 38, and a screw 38b is formed at an inner end of the output shaft 38.
b, a nut 42 is screwed into the output shaft 38.
And the wheel hub 39 are prevented from moving in the axial direction with respect to each other. Further, a seal 59 is provided between the opening and the sleeve portion 39a so that oil in the motor chamber 15 does not leak out of the drive device case 11 through the opening.

A motor 24 is provided in the motor chamber 15, and a stator 25 is fixed to the cylindrical portion 12a of the first casing 12 by bolts b11. The stator 25 includes a stator core 25a and a stator coil 26 wound around the stator core 25a. The rotor 27 is disposed radially inward of the stator core 25a with a predetermined gap (gap) therebetween.
It is arranged rotatably with respect to. The rotor 27 includes a rotor shaft 21, a rotor hub 27a fixed to the rotor shaft 21, and a rotor core 27b fixed to an outer peripheral edge of the rotor hub 27a.
Permanent magnets 27d are arranged at a plurality of locations in the circumferential direction of 7b.

The outer end of the rotor shaft 21 is connected to a bearing 28 with respect to the first casing 12.
The inner end of the rotor shaft 21 is rotatably supported by the bearing 33 with respect to the flange portion 38 a of the output shaft 38. A planetary gear unit 31 as a transmission gear device is disposed radially inward of the motor 24. In this case, the motor 2
4 and the planetary gear unit 31 are overlapped in the axial direction, so that the axial size of the vehicle motor drive device can be reduced. The planetary gear unit 31 is rotatably supported by the sun gear S and the ring gear R spline-engaged with the rotor shaft 21, the carrier CR formed by the flange portion 38 a, and the carrier CR. The rotation generated by the motor 24 is transmitted to the sun gear S, and the decelerated rotation is output to the output shaft 38. The ring gear R is fixed to a ring gear flange 14 fixed to the second casing 13 by bolts b1.

A wheel disc 45 has bolts b2 on the outer periphery of the flange portion 39b of the wheel hub 39.
Fixed by The wheel disc 45 has a cup-shaped shape, and has a flat bottom 45a.
And a cylindrical portion 45b integrally formed on the outer periphery of the bottom portion 45a, and a tire 47 is attached to an outer edge of the cylindrical portion 45b.
Is fixed.

By the way, the stator coil 26 generates heat as the motor 24 is driven. In addition, frictional heat is generated with the operation of the planetary gear unit 31. Therefore, an oil reservoir (not shown) is formed in the lower part of the motor chamber 15, and the oil accumulated in the oil reservoir is
It is scraped up by a rotor 27 and supplied to a predetermined location. For this purpose, a predetermined amount of oil is filled in the motor chamber 15 so that the lowermost portion of the rotor 27 is immersed in the oil. Then, when the oil in the oil reservoir is scraped up by the rotor 27, it is moved upward along the inner wall of the drive device case 11 and falls from above to cool the stator coil 26.

However, the planetary gear unit 3
1 is arranged not only radially inward of the rotor 27 but also
Since the oil is surrounded by the rotor hub 27a, the ring gear flange 14, and the like, the dropped oil is not sufficiently supplied to the planetary gear unit 31. Therefore, the first rib 51 is provided on the top of the inner wall of the first casing
It is formed so as to protrude toward the fifth side. The first rib 51 is provided between the stator coil 26 and the rotor core 27b.
And has a length that is opposite to that of the oil, extends in the vertical direction, and regulates the circumferential movement of the scraped-up oil.

A second rib 52 is formed at a predetermined distance from the lower end of the first rib 51 so as to protrude toward the stator 25. The second rib 52
Extends almost horizontally, with both ends facing the stator coil 26 and extending in the horizontal direction, thereby restricting the vertical movement of the scooped oil. The left and right portions of the second rib 52 are inclined so as to be lower as approaching the center.
The first and second ribs 51 and 52 constitute a guide member.

The first casing 12 includes:
Directly above the center of the second rib 52, and
Immediately below the first rib 51, a first oil passage 53 is formed so as to open toward the rotor hub 27a. The first oil passage 53 is connected to a second oil passage 54 extending radially and vertically in the first casing 12, and the second oil passage 54 is connected to the first casing 12. Is connected to a third oil passage 55 that extends in the rotor shaft 21 in the axial direction and horizontally. Further, the third oil passage 55 is connected to a fourth oil passage 56 extending in the radial direction inside the rotor shaft 21, and the fourth oil passage 56 faces the planetary gear unit 31 on the surface of the rotor shaft 21. It is opened.

Therefore, part of the oil that has moved upward along the inner wall of the drive device case 11 is part of the first rib 51.
And falls on the second rib 52 to be supplied to the first oil passage 53. And the rest of the oil,
That is, the oil that has bounced off the first rib 51 also falls on the second rib 52, is guided by the second rib 52, and is supplied to the first oil passage 53. Further, the oil that has hit below the second rib 52 along the inner wall of the drive device case 11 lubricates the sun gear S and the bearing 28.

Then, the oil supplied to the first oil passage 53 passes through the second to fourth oil passages 54 to 56 in order, and from the opening of the fourth oil passage 56 by the centrifugal force of the rotor shaft 21. It is discharged and lubricates the planetary gear unit 31. Therefore, the scraped-up oil can be sufficiently supplied to the planetary gear unit 31, so that the planetary gear unit 31 can be satisfactorily lubricated.

Further, since the oil is discharged from the opening of the fourth oil passage 56 by centrifugal force, a sufficient amount of oil to be supplied to the planetary gear unit 31 can be secured. In addition, since the amount of oil discharged increases with the rotation speed of each gear element of the rotor 27 and the planetary gear unit 31, the lubrication efficiency can be increased.

Since there is no need to use an oil pump or the like to supply oil to the planetary gear unit 31, the motor drive device for the vehicle can be reduced in size. In order to detect the rotation speed of the rotor 27, an annular protrusion 94 is formed at a predetermined position of the rotor 27, and a plurality of ring magnets 95 are formed on the inner peripheral side of the annular protrusion 94 in correspondence with the permanent magnets 27d. Is done. A Hall element 62 is provided in the drive device case 11 so as to face the ring magnet 95. In this case, the Hall element 62 is fixed to the first casing 12 by a bolt (not shown) attached to a bolt hole 61 below the second rib 52, but falls near the first rib 51. The collected oil is collected by the second rib 52 and supplied to the first oil passage 53, so that the oil can be prevented from adhering to the Hall element 62. Therefore, since the temperature of the Hall element 62 does not change,
Does not change. As a result, a change in the drive characteristics of the motor 24 can be suppressed.

In the present embodiment, the Hall element 62 is provided at one place in the circumferential direction of the annular projection 94, but may be provided at a plurality of places as needed. In this case, the detection accuracy of the rotation speed of the rotor 27 and the detection accuracy of the position of the rotor 27 can be increased. It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0022]

As described above in detail, according to the present invention, in a motor drive device for a vehicle, a drive device case, a stator fixed to the drive device case, and a radially inward portion of the stator are provided. A rotor rotatably disposed in the above, a transmission gear device disposed radially inward of the rotor and receiving a rotation of the rotor to perform a speed change, and an oil passage formed facing the transmission gear device. And a guide member formed on the inner wall of the drive device case and guiding the oil scooped up with the rotation of the rotor to the oil passage.

In this case, when the rotor is rotated as the motor is driven, the oil in the drive device case is scraped up and cools the stator coil. Further, the scooped oil is guided to the oil passage by the guide member and supplied to the transmission gear device to lubricate the transmission gear device. Therefore, the oil scooped up by the rotor can be sufficiently supplied to the transmission gear device, so that the transmission gear device can be favorably lubricated.

Further, since there is no need to use an oil pump or the like to supply oil to the transmission gear device, it is possible to reduce the size of the vehicle motor drive device. In another vehicle motor drive device of the present invention, the guide member is formed integrally with the drive device case, extends in the vertical direction, and regulates the circumferential movement of the scraped-up oil.
And a second rib extending substantially horizontally and restricting vertical movement of the scooped oil.

In this case, the scrubbed oil moves upward along the inner wall of the drive device case, falls from the first rib onto the second rib, and is guided by the second rib. Supplied to the oil passage. In addition, since the second rib extends in the horizontal direction, it is possible to prevent oil from adhering to the Hall element disposed below the second rib. Therefore, since the temperature of the Hall element does not change, the operating magnetic flux density of the Hall element does not change. As a result, a change in the driving characteristics of the motor can be suppressed, so that a desired driving force can be generated, and the efficiency of the motor can be increased.

In still another motor drive device for a vehicle according to the present invention, the oil passage extends radially in the first oil passage opening directly above the second rib and in the drive device case. It comprises a second oil passage, a third oil passage extending in the rotor shaft in the axial direction, and a fourth oil passage extending in the rotor shaft in the radial direction. In this case, since the oil is discharged from the opening of the fourth oil passage by centrifugal force, it is possible to sufficiently secure the amount of oil supplied to the transmission gear device. In addition, the amount of oil discharged increases as the rotation speed of each gear element of the rotor and the transmission gear device increases, so that lubrication efficiency can be increased.

Since there is no need to use an oil pump or the like to supply oil to the transmission gear device, the motor drive device for a vehicle can be reduced in size.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a vehicle motor drive device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a drive device case according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 11 drive device case 21 rotor shaft 25 stator 27 rotor 31 planetary gear unit 51 first rib 52 second rib 53 first oil passage 54 second oil passage 55 third oil passage 56 fourth oil passage

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D035 DA02 3J063 AA01 AA04 AB12 BA11 BB41 BB46 CA01 CA10 CB02 CD41 XD03 XD16 XD33 XD43 XD47 XD62 XD71 XE15 XF12

Claims (3)

[Claims] 1. A driving device case, a stator fixed to the driving device case, a rotor rotatably disposed radially inward of the stator, and a rotor disposed radially inward of the rotor. A transmission gear device that performs a shift by receiving rotation of a rotor, an oil passage formed facing the transmission gear device, and an inner wall of the drive device case, which is scraped up with the rotation of the rotor. And a guide member for guiding the oil to the oil passage. 2. The guide member is formed integrally with a drive device case, extends in the vertical direction, and has a first rib for restricting circumferential movement of the scooped oil, and extends in a substantially horizontal direction. The motor drive device for a vehicle according to claim 1, further comprising a second rib that regulates vertical movement of the scooped oil. 3. The oil passage includes a first oil passage that is opened immediately above the second rib, a second oil passage that extends in the drive device case in a radial direction, and an axial direction that extends in a rotor shaft. The motor drive device for a vehicle according to claim 2, comprising a third oil passage and a fourth oil passage extending radially in the rotor shaft.