JP2014092216A - Driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving device capable of improving efficiency for exhausting lubrication oil from an exhaust hole by restraining the lubrication oil from being waved on an inner periphery of a rotor shaft even during high-speed rotation of a rotor.SOLUTION: A driving device 1 comprises a motor 4, a motor shaft 5 having a first exhaust hole 61, a pump driving shaft 7, and an oil pump 8. The pump driving shaft 7 has: a first receiver 62 having a second exhaust hole 60, provided on one axial side of the first exhaust hole 61 and the second exhaust hole 60, and having a first extension part 62a on an inner periphery of the motor shaft 5; and a second receiver 63 provided on the other axial side of the first exhaust hole 61 and the second exhaust hole 60, and having a second extension part 63a on the inner periphery of the motor shaft 5. At least one of the first receiver 62 and the second receiver 63 has a cylindrical part 62b extending toward the other receiver and not overlaid on the second exhaust hole 60 in an axial direction.

Description

  The present invention relates to a drive device mounted on, for example, a hybrid vehicle or an electric vehicle, and more specifically, a drive device that supplies lubricating oil supplied to the inner peripheral side of a hollow rotor shaft to the rotor of a rotating electrical machine on the outer peripheral side. About.

  In recent years, various vehicles equipped with a motor / generator (hereinafter also referred to as “motor”) such as a hybrid vehicle and an electric vehicle have been proposed in order to improve vehicle fuel efficiency and environmental performance. A vehicle equipped with this type of motor is provided with a drive unit that supplies lubricating oil to the rotor and the stator in order to cool the motor.

  As a driving device, for example, lubricating oil that has flowed down from an oil sump provided at the top of the case is allowed to flow from the end of the hollow rotor shaft to the inner peripheral side, and the inside and outside formed on a part of the rotor shaft A configuration is known in which lubricating oil is discharged from an inner peripheral side to an outer peripheral side by centrifugal force from a communicating discharge hole, and the motor is cooled by supplying the lubricating oil to a rotor (see Patent Document 1). According to this drive device, the motor can be cooled by the lubricating oil with a simple configuration.

JP 2011-89636 A

  However, in the driving device of Patent Document 1, when the rotor (11) rotates at a high speed, the lubricating oil adhering to the inner peripheral surface of the rotor shaft (31) by centrifugal force undulates, and the discharge hole (59) portion. However, the oil level on the inner circumferential surface of the rotor shaft (31) varies. As a result, the amount of lubricating oil discharged from the discharge hole (59) becomes non-uniform, and the efficiency of discharging the lubricating oil from the discharge hole (59) is lower than when the rotor (11) is rotated at a low speed. As a result, there is a problem that the motor cooling efficiency is lowered.

  Accordingly, the present invention provides a drive device that can suppress the occurrence of lubricating oil on the inner peripheral surface of the rotor shaft even during high-speed rotation of the rotor and improve the efficiency of discharging the lubricating oil from the discharge hole. It is the purpose.

The drive device (1) according to the present invention (see, for example, FIG. 1) includes a rotating electrical machine (4) having a rotor (41)
It is a hollow tube, and can rotate integrally with the rotor (41) provided on the outer peripheral side, and communicates the inner peripheral side and the outer peripheral side for supplying oil circulating on the inner peripheral side to the rotor (41). A rotor shaft (5) having a first discharge hole (61);
A hollow tubular supply shaft (7) inserted on the inner peripheral side of the rotor shaft (5);
In a drive device (1) comprising: a lubricant supply means (8) for supplying lubricant to the inner peripheral side of the supply shaft (7),
The supply shaft (7) has a second discharge hole (60) for supplying lubricating oil on the inner peripheral side of the supply shaft (7) to the inner peripheral side of the rotor shaft (5),
A first extending portion provided on one axial side of the first discharge hole (61) and the second discharge hole (60) and extending from the inner peripheral surface of the rotor shaft (5) to the inner diameter side. A first receiver (62) having (62a);
A second extending portion provided on the other axial side of the first discharge hole (61) and the second discharge hole (60) and extending from the inner peripheral surface of the rotor shaft (5) to the inner diameter side. A second receiver (63) having (63a),
At least one of the first receiver (62) and the second receiver (63) extends toward the other receiver (62, 63), and the second discharge hole ( 60) and has a cylindrical portion (62b) that does not overlap.

  The drive device (1) according to the present invention (see, for example, FIG. 1) is characterized in that the cylindrical portion (62b) is formed to overlap the first discharge hole (61) in the axial direction. To do.

Furthermore, the drive device (1) according to the present invention (see, for example, FIG. 1), the first receiver (62) includes the cylindrical portion (62b),
The second receiver (63) has a guide portion (63b) having an enlarged inner diameter on the first discharge hole (61) side at a position overlapping the second discharge hole (60) in the axial direction. It is characterized by having.

  In addition, although the code | symbol in the said parenthesis is for contrast with drawing, this is for convenience for making an understanding of invention easy, and has no influence on the structure of a claim. It is not a thing.

  According to the first aspect of the present invention, even when the rotor rotates at a high speed, it is possible to suppress the lubricating oil from undulating on the inner peripheral surface of the rotor shaft, and to lubricate from the first discharge hole as compared with the conventional driving device. The amount of oil discharged can be stabilized, and the efficiency of lubricating oil discharge can be improved.

  According to the second aspect of the present invention, it is possible to further stabilize the discharge amount from the first discharge hole and further improve the discharge efficiency of the lubricating oil.

  According to the third aspect of the present invention, the lubricating oil discharged from the second discharge hole can be efficiently guided to the first discharge hole side without being scattered by the inner peripheral surface of the rotor shaft.

Sectional drawing which shows the drive device which concerns on embodiment of this invention. Sectional drawing which shows the drive device which concerns on other embodiment of this invention.

  Hereinafter, the structure of the drive device according to the embodiment of the present invention will be described with reference to FIG. In addition, the drive device 1 in this Embodiment shall be applied to the hybrid vehicle, for example.

  A drive device 1 includes a motor shaft (rotor shaft) 5, an input shaft 3, a pump drive shaft (supply shaft) 7, a motor / generator (rotary electric machine) 4, a resolver 9, an oil pump (lubricating oil supply means). 8) It has a motor cooling mechanism 6 and the like. In the present embodiment, an engine (not shown) is arranged on the right side in FIG. 1, and the crankshaft of the engine is connected to the input shaft 3 via a flywheel (not shown).

  The case 2 includes a main case 20 that is open on the side opposite to the engine side in the axial direction, that is, the oil pump 8 side, and a case cover 21 that closes the opening of the main case 20. The case 2 supports the motor shaft 5, the pump drive shaft 7, and the input shaft 3 so as to be rotatable on the same axis.

  The motor shaft 5 has a hollow tube shape and is rotatably supported by a ball bearing 50 a supported by the main case 20 and a ball bearing 50 b supported by the case cover 21. The motor shaft 5 is connected to the input shaft 3 via a differential gear mechanism. The motor shaft 5 rotatably supports a rotor 41 of the motor 4 described later. Further, a stopper portion 5a having a diameter increased in a flange shape is formed in the vicinity of the oil pump 8 side of the ball bearing 50a on the outer peripheral side of the motor shaft 5. A rotor 41, which will be described later, is in contact with the stopper portion 5a in the axial direction.

  The pump drive shaft 7 is inserted into the motor shaft 5 and has a hollow tubular shape that can be rotated on the inner peripheral side thereof. The slide bearing 70 is supported so as to be rotatable. The pump drive shaft 7 is connected to an oil pump 8 described later, and drives the oil pump 8 by transmitting the rotational force of the engine to the oil pump 8.

  The motor 4 is provided on the outer peripheral side of the motor shaft 5. The motor 4 includes a stator 40 that is fixed to the main case 20 and a rotor 41 that is fixed to the outer peripheral side of the motor shaft 5 and rotates integrally. A so-called IPM motor in which a permanent magnet is embedded in the rotor 41. Consists of.

  The stator 40 has an annular stator core 40a and a coil end 40b. The stator core 40a is composed of a large number of laminated steel plates, and stator windings are embedded therein and fastened to the main case 20 with bolts (not shown). The coil ends 40b are formed on both sides of the stator core 40a in the axial direction so as to protrude from the stator core 40a in order to return the stator winding.

  The rotor 41 includes a cylindrical rotor core 42, a first end plate 43, a second end plate 44, and a stopper 45.

  The rotor core 42 is composed of a number of steel plates stacked in the same manner as the stator core 40a, and is composed of, for example, permanent magnets embedded therein. The rotor core 42 is formed with an in-core oil passage 67 which will be described later.

  The first end plate 43 has a disk shape and is provided in contact with the end surface of the rotor core 42 on the engine side. The first end plate 43 is formed with an introduction oil passage 64, a first annular oil passage 65, and a first through hole 66, which will be described later.

  The second end plate 44 has a disc shape and is provided in contact with the end surface of the rotor core 42 on the oil pump 8 side. The second end plate 44 is formed with a second annular oil passage 68 and a second through hole 69 which will be described later.

  The stopper 45 has a disc shape and is provided in contact with the end surface of the second end plate 44 on the oil pump 8 side. The stopper 45 is fixed to the motor shaft 5 by fitting or welding. The second end plate 44, the rotor core 42, and the first end plate 43 are sequentially directed toward the stopper portion 5a of the motor shaft 5 in the axial direction. Press and fix. Thereby, the entire rotor 41 rotates integrally with the motor shaft 5.

  The resolver 9 is disposed near the end of the motor shaft 5 on the oil pump 8 side. The resolver 9 includes a resolver rotor 91 fixed to the outer peripheral side of the motor shaft 5 and a resolver stator 92 fastened to the case cover 21 with bolts 90. The resolver 9 detects the rotational position (phase) of the rotor 41 and transmits the result to a control unit (not shown). The controller refers to the detected value of the rotational position of the rotor 41 by the resolver 9 and controls the rotation of the motor 4.

  The oil pump 8 is connected to the tip of the pump drive shaft 7. The oil pump 8 is composed of, for example, a trochoid pump, a gear pump, or the like, and supplies lubricating oil to the inner peripheral side of the pump drive shaft 7. The lubricating oil discharged from the oil pump 8 flows through the inner peripheral side of the pump drive shaft 7 and is supplied to the differential gear mechanism to lubricate the differential gear mechanism.

  The motor cooling mechanism 6 is provided in the vicinity of the motor 4. The motor cooling mechanism 6 includes a second discharge hole 60, a first discharge hole 61, a first receiver 62, a second receiver 63, an introduction oil passage 64, a first annular oil passage 65, and a first through hole. 66, an in-core oil passage 67, a second annular oil passage 68, and a second through hole 69 are provided.

  The second discharge hole 60 is provided in the pump drive shaft 7 and communicates the inner peripheral side and the outer peripheral side of the pump drive shaft 7. The second discharge hole 60 discharges the lubricating oil flowing on the inner peripheral side of the pump drive shaft 7 to the outer peripheral side by centrifugal force and supplies it to the inner peripheral side of the motor shaft 5. The second discharge hole 60 is formed near the central portion of the rotor 41 in the axial direction. For example, the second discharge hole 60 has a diameter of about 1.8 mm and is formed in a single circumferential direction. However, the diameter and number of the second discharge holes 60 can be appropriately set according to the amount of lubricating oil to be discharged and other conditions.

  The first discharge hole 61 is provided in the motor shaft 5 and communicates the inner peripheral side and the outer peripheral side of the motor shaft 5. The first discharge hole 61 discharges oil on the inner peripheral side of the motor shaft 5, for example, lubricating oil to the outer peripheral side by centrifugal force, and supplies the oil to the rotor 41 through a path described later. The first discharge hole 61 is formed in an end surface on the engine side of the rotor core 42 so as to open to an introduction oil passage 64 described later. For example, the first discharge hole 61 has a diameter of about 1.8 mm and is formed only in the circumferential direction. However, the diameter and number of the first discharge holes 61 can be appropriately set according to the amount of lubricating oil to be discharged and other conditions.

  The first receiver 62 is a separate member from the motor shaft 5 and is attached to the inner peripheral side of the motor shaft 5 by welding or the like. The first receiver 62 is provided on the engine side (one side) in the axial direction of the first discharge hole 61 and the second discharge hole 60, and has a first extending portion 62a and a cylindrical portion 62b. doing.

  The first extending portion 62 a has a shape extending from the inner peripheral surface of the motor shaft 5 to the inner diameter side. The cylindrical portion 62b is formed to extend in the axial direction from the inner peripheral side end portion of the first extending portion 62a toward the second receiver 63 side described later. The length of the cylindrical portion 62b is a length that does not overlap with the second discharge hole 60 in the axial direction, that is, a length up to a position facing the second discharge hole 60 in the radial direction at the longest. In the present embodiment, the cylindrical portion 62 b is formed to extend further to the second receiver 63 side than the first discharge hole 61. In other words, the cylindrical portion 62b is formed so as to overlap the first discharge hole 61 in the axial direction, that is, to face the first discharge hole 61 in the radial direction.

  The second receiver 63 is a separate member from the motor shaft 5 and is attached to the inner peripheral side of the motor shaft 5 by welding or the like. The second receiver 63 is provided on the oil pump 8 side (the other side) in the axial direction of the first discharge hole 61 and the second discharge hole 60, and includes a second extending portion 63a, a guide portion 63b, have.

  The second extending portion 63 a has a shape extending from the inner peripheral surface of the motor shaft 5 to the inner diameter side. The guide portion 63b has a first discharge hole at a position overlapping the second discharge hole 60 in the axial direction, that is, at a position facing the second discharge hole 60 in the radial direction, or closer to the oil pump 8 than that. The inner diameter on the 61 side is increased. In the present embodiment, the guide portion 63b is formed nearer to the oil pump 8 than the position overlapping the second discharge hole 60 in the axial direction, but overlaps the second discharge hole 60 in the axial direction. You may form in the position to do. Further, in the present embodiment, the guide portion 63b is formed to have an inclined surface that is inclined by increasing the inner diameter on the first discharge hole 61 side. The guide part 63b guides the lubricating oil discharged from the second discharge hole 60 to the first discharge hole 61 side by flowing the lubricant oil along the inclined surface to the outer peripheral side. In addition, the inclined surface which comprises the guidance | induction part 63b may be either a plane and a curved surface.

  The introduction oil passage 64, the first annular oil passage 65, and the first through hole 66 are all formed in the first end plate 43. The first annular oil passage 65 is formed on the rotor core 42 side, and is formed by an annular recess centered on the motor shaft 5. The introduction oil passage 64 is formed by a radial groove that communicates the first discharge hole 61 and the first annular oil passage 65 on the rotor core 42 side. The first through holes 66 penetrate from the first annular oil passage 65 to the end surface on the engine side in the axial direction, and are formed at several locations at equal intervals in the circumferential direction.

  Both the second annular oil passage 68 and the second through hole 69 are formed in the second end plate 44. The second annular oil passage 68 is formed on the rotor core 42 side, and is formed by an annular recess centered on the motor shaft 5. The second through holes 69 penetrate the end surface on the oil pump 8 side from the second annular oil passage 68 in the axial direction, and are formed at several locations at equal intervals in the circumferential direction.

  The in-core oil passage 67 is formed so as to penetrate the rotor core 42 in the axial direction, the end on the engine side communicates with the first annular oil passage 65, and the end on the oil pump 8 side is the second end. It communicates with the annular oil passage 68.

Three in-core oil passages 67 are provided at equal intervals in the circumferential direction of the rotor 41. Note that the number of oil passages 67 in the core is not limited to three, and can be set as appropriate according to the amount of lubricating oil discharged and the degree of cooling of the coil end 40b.

  The operation of the driving device 1 described above will be described below. Here, the case where the engine is being driven and regeneration is performed by the motor 4 will be described.

  The rotational force of the engine is transmitted from the crankshaft through the input shaft 3 to the pump drive shaft 7 to rotate the pump drive shaft 7 and to the motor shaft 5 through the differential gear mechanism to rotate the motor shaft 5. . The oil pump 8 is actuated by the rotation of the pump drive shaft 7. The lubricating oil discharged from the oil pump 8 flows into the inner peripheral side of the pump drive shaft 7.

  Further, the motor cooling mechanism 6 is operated by the rotation of the pump drive shaft 7 and the motor shaft 5. Hereinafter, the operation of the motor cooling mechanism 6 will be described in detail.

  The lubricating oil that has flowed into the inner peripheral side of the pump drive shaft 7 spreads and adheres evenly to the inner wall of the pump drive shaft 7 in the circumferential direction due to centrifugal force. The lubricating oil in the vicinity of the second discharge hole 60 is discharged from the second discharge hole 60 to the outer peripheral side of the pump drive shaft 7 by centrifugal force.

  Since the guide portion 63b is disposed in the vicinity of the portion of the pump drive shaft 7 facing the second discharge hole 60, a part of the lubricating oil discharged from the second discharge hole 60 is sprayed onto the guide portion 63b. It is done. Since the guide portion 63b has an inclined surface that is inclined by increasing the inner diameter of the first discharge hole 61, the lubricating oil is circulated on the outer peripheral side along the inclined surface and is guided to the first discharge hole 61 side. Is done.

  Lubricating oil guided from the guiding portion 63b to the first discharge hole 61 side is stored in a space defined by the first extending portion 62a and the guiding portion 63b, and the cylindrical portion 62b and the inner wall of the motor shaft 5 Therefore, even when the rotor 41 rotates at high speed, the cylindrical portion 62b suppresses the undulation of the lubricating oil. The lubricating oil flowing between the cylindrical portion 62b and the inner wall of the motor shaft 5 is discharged from the first discharge hole 61 to the outer peripheral side of the motor shaft 5 by centrifugal force.

  The lubricating oil discharged from the first discharge hole 61 circulates from the introduction oil passage 64 to the in-core oil passage 67 through the first annular oil passage 65 by centrifugal force as indicated by an arrow in FIG. The lubricating oil cools the rotor core 42 when flowing through the in-core oil passage 67. Furthermore, as indicated by the arrow, the lubricating oil that has circulated through the in-core oil passage 67 is supplied from the first annular oil passage 65 through the first through hole 66 to the coil end 40b by centrifugal force, The second annular oil passage 68 is supplied to the coil end 40b by centrifugal force through the first through hole 66. The coil end 40 b is cooled by supplying lubricating oil from the first through hole 66 and the second annular oil passage 68.

  As described above, according to the driving device 1 of the present embodiment, the lubricating oil discharged from the second discharge hole 60 is stored in the space defined by the first extending portion 62a and the guide portion 63b. And flows between the cylindrical portion 62b and the inner wall of the motor shaft 5. That is, the lubricating oil is stored in the first receiver 62 and the second receiver 63, and the oil surface of the lubricating oil is suppressed to the height of the inner wall of the cylindrical portion 62b by suppressing the undulation by the cylindrical portion 62b. become. Therefore, the amount of lubricating oil discharged from the first discharge hole 61 can be stabilized as compared with the conventional driving device, and the lubricating oil discharging efficiency can be improved.

  Further, according to the driving device 1 of the present embodiment, the cylindrical portion 62b is provided so as to overlap the first discharge hole 61 in the axial direction, that is, to face in the radial direction. The undulation of the lubricating oil flowing in the vicinity of the discharge hole 61 is suppressed by the cylindrical portion 62b, the discharge amount from the first discharge hole 61 is further stabilized, and the discharge efficiency of the lubricating oil is further improved. Can do.

  Furthermore, according to the driving device 1 of the present embodiment, since the guide portion 63b is formed in the vicinity of the position facing the second discharge hole 60 in the radial direction, the lubrication discharged from the second discharge hole 60 The oil is guided to the first discharge hole 61 side, and is prevented from colliding with the inner wall of the motor shaft 5 and scattering. Accordingly, the lubricating oil discharged from the second discharge hole 60 can be efficiently guided to the first discharge hole 61 side without being scattered.

  In addition, in the drive device 1 of this Embodiment demonstrated above, the case where the 2nd receiver 63 had the guidance | induction part 63b was demonstrated. However, the drive device according to the present invention is not limited to this. For example, when the lubricating oil discharged from the second discharge hole 60 is a small amount and hardly collides with the inner wall of the motor shaft 5, The guide part 63b may not be provided.

  Moreover, in the drive device 1 of this Embodiment, the case where the cylindrical part 62b overlapped with the 1st discharge hole 61 in the axial direction was demonstrated. However, the drive device according to the present invention is not limited to this, and for example, the cylindrical portion 62b may not overlap the first discharge hole 61 in the axial direction. In this case, the second discharge hole 60 can be provided at a position facing the first discharge hole 61 in the radial direction.

  Moreover, in the drive device 1 of this Embodiment, the case where only the 1st receiver 62 had the cylindrical part 62b was demonstrated. However, the drive device according to the present invention is not limited to this, and for example, only the second receiver 63 may have a cylindrical portion, or both the first receiver 62 and the second receiver 63 are respectively provided. You may make it have a cylindrical part.

  Here, in FIG. 2, in the motor cooling mechanism 106, neither the first receiver 162 nor the second receiver 163 has a guiding portion, and the first receiver 162 includes the first extending portion 162 a and the first extending portion 162 a. The second receiver 163 has a second extending part 163a and a cylindrical part 163b that does not face the first discharge hole 161, and the second discharge hole 160 has a cylindrical part 162b that does not face the first discharge hole 161. Shows a configuration in the case where is provided at a position facing the first discharge hole 161 in the radial direction.

  Also in this case, the lubricating oil discharged from the second discharge hole 160 is stored in a space defined by the receivers 162 and 163 without colliding with the receivers 162 and 163 and scattering. Therefore, even when the rotor 41 rotates at high speed, the lubricating oil stored in the space defined by the receivers 162 and 163 can stabilize the oil level up to the height of the cylindrical portions 162b and 163b.

  Moreover, in the drive device 1 of this Embodiment, the case where both the 1st receiver 62 and the 2nd receiver 63 were separate members from the motor shaft 5 was demonstrated. However, the drive device according to the present invention is not limited to this, and at least one of the first receiver 62 and the second receiver 63 may be the same member as the motor shaft 5.

  Moreover, in the drive device 1 of this Embodiment, the case where the motor 4 was comprised with the IPM motor was demonstrated. However, the drive device according to the present invention is not limited to this, and for example, an SPM motor, a reluctance motor, or the like may be used, that is, the motor 4 may be any type of motor.

  Moreover, in the drive device 1 of this Embodiment, the case where the drive device 1 was applied to a hybrid vehicle was demonstrated. However, the drive device according to the present invention is not limited to this, and can be applied to all vehicles equipped with a rotating electrical machine such as an electric vehicle.

1 Drive 4 Rotating electrical machine (motor / generator)
5 Rotor shaft (motor shaft)
7 Supply shaft (pump drive shaft)
8 Lubricating oil supply means (oil pump)
6, 106 Motor cooling mechanism 41 Rotors 60, 160 Second discharge holes 61, 161 First discharge holes 62, 162 First receivers 62a, 162a First extending portions 62b, 162b, 163b Cylindrical portions 63, 163 2nd receiver 63a, 163a 2nd extension part 63b guidance | induction part

Claims (3)

A rotating electric machine having a rotor;
A hollow discharge tube that is integrally rotatable with the rotor provided on the outer peripheral side, and has a first discharge hole that communicates the inner peripheral side and the outer peripheral side for supplying oil flowing through the inner peripheral side to the rotor. A rotor shaft having,
A hollow tubular supply shaft inserted on the inner peripheral side of the rotor shaft;
In a drive device comprising: a lubricant supply means for supplying lubricant to the inner peripheral side of the supply shaft;
The supply shaft has a second discharge hole for supplying lubricating oil on the inner peripheral side of the supply shaft to the inner peripheral side of the rotor shaft,
A first receiver provided on one side in the axial direction of the first discharge hole and the second discharge hole and having a first extending portion extending from an inner peripheral surface of the rotor shaft to an inner diameter side;
A second receiver provided on the other axial side of the first discharge hole and the second discharge hole and having a second extending portion extending from the inner peripheral surface of the rotor shaft to the inner diameter side; Prepared,
At least one of the first receiver and the second receiver has a cylindrical portion that extends toward the other receiver and does not overlap the second discharge hole in the axial direction.
A drive device characterized by that. The cylindrical portion is formed to overlap the first discharge hole in the axial direction.
The drive device according to claim 1. The first receiver has the cylindrical portion,
The second receiver has a guide portion having an enlarged inner diameter on the first discharge hole side at a position overlapping with the second discharge hole in the axial direction.
The drive device according to claim 1, wherein

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