WO2019049465A1

WO2019049465A1 - Drive device

Info

Publication number: WO2019049465A1
Application number: PCT/JP2018/023305
Authority: WO
Inventors: 山口　康夫
Original assignee: 日本電産株式会社
Priority date: 2017-09-08
Filing date: 2018-06-19
Publication date: 2019-03-14
Also published as: CN111033971A; CN111033971B

Abstract

The housing in one embodiment of the drive device of the present invention is provided with a pump chamber, and has an outer lid section for covering one side of a motor shaft in the axial direction thereof, and a first oil channel which is connected to a discharge port and is provided in the outer lid section. The outer lid section has a shaft insertion hole into which the motor shaft is inserted. The motor shaft has a second oil channel which is connected to the first oil channel and is provided inside the motor shaft, a first through-hole which connects the second oil channel and the outer-circumferential surface of the motor shaft to one another, and a second through-hole which connects the second oil channel and the outer-circumferential surface of the motor shaft to one another, and is positioned toward the one side in the axial direction relative to the first through-hole. The first through-hole is connected to the inside of the storage section. The first oil channel includes a groove which recesses toward the other side in the axial direction from the pump chamber surface on the other side thereof in the axial direction. The end section of the first oil channel toward the inside in the radial direction opens to the shaft insertion hole. The second through-hole opens to the outer-circumferential surface of the motor shaft section inserted into the shaft insertion hole, and is connected to the first oil channel via the shaft insertion hole.

Description

Drive unit

The present invention relates to a drive device.

There is known an electric rotating machine provided with a case for storing a lubricating fluid for lubricating and cooling such as a stator and a rotor. For example, Japanese Patent Laid-Open Publication No. 2013-055728 describes a rotating electrical machine mounted on a vehicle.

Japanese Published Patent Application Publication No. 2013-055728

The above-described rotating electrical machine may be provided with a pump unit that sucks up the oil stored in the case. The rotor and the stator can be cooled by sucking up the oil by the pump unit and supplying the oil to the rotor and the stator, for example. In this case, it is conceivable to provide an oil passage in the shaft of the rotary electric machine, send oil to the oil passage in the shaft by the pump unit, and supply oil to the stator or the like from the oil passage in the shaft. However, in this case, since it is necessary to provide an oil passage for guiding the oil from the pump portion to the oil passage in the shaft, there is a case where the rotary electric machine becomes large in the axial direction.

In view of the above-described circumstances, the present invention has an object to provide a drive device having a pump portion that sends oil to an oil passage provided inside a motor shaft and having a structure that can be miniaturized in the axial direction. One.

According to one aspect of the drive device of the present invention, a rotor having a motor shaft disposed along a central axis extending in one direction and a rotor core fixed to the motor shaft is radially opposed to the rotor via a gap. , A housing for accommodating the rotor and the stator and having an accommodation portion capable of storing oil, and a pump portion driven via the motor shaft, the pump portion being a motor shaft of the motor shaft An external gear fixed to one end in the axial direction, an internal gear that surrounds the radial outer side of the external gear, and engages with the external gear, and accommodates the internal gear and the external gear A pump chamber, a suction port capable of suctioning oil into the pump chamber, and a discharge port capable of discharging oil from the pump chamber; An outer cover portion provided with a pump chamber and covering one axial side of the motor shaft; and a first oil passage provided in the outer cover portion and connected to the discharge port; The outer cover portion is penetrated from the surface on the other side in the axial direction of the pump chamber to the surface on the other side in the axial direction of the outer cover portion, and the motor shaft has a shaft insertion hole through which the motor shaft passes. A second oil passage provided inside the motor shaft and connected to the first oil passage, a first through hole connecting the second oil passage and the outer peripheral surface of the motor shaft, and a diameter larger than the first through hole And a second through hole disposed on one side in the axial direction and connecting the second oil passage and the outer peripheral surface of the motor shaft, the first through hole being connected to the inside of the storage portion, 1 oil passage includes a groove recessed from the surface on the other side in the axial direction of the pump chamber to the other side in the axial direction, The radially inner end of the first oil passage opens in the shaft insertion hole, and the second through hole opens in the outer peripheral surface of the portion of the motor shaft inserted in the shaft insertion hole, It connects with the said 1st oil path via a shaft insertion hole.

According to one aspect of the present invention, there is provided a drive device having a pump portion for feeding oil to an oil passage provided inside the motor shaft and having a structure that can be miniaturized in the axial direction.

FIG. 1 is a cross-sectional view showing the drive device of the first embodiment. FIG. 2 is a cross-sectional view showing a part of the drive device of the first embodiment. FIG. 3 is a view of the pump unit of the first embodiment as viewed from the other side in the axial direction. FIG. 4 is a cross-sectional view showing a part of the drive device of the first embodiment. FIG. 5 is a cross-sectional view showing a part of a drive device which is another example of the first embodiment. FIG. 6 is a cross-sectional view showing a part of the drive device of the second embodiment.

The Z-axis direction shown in each drawing is the vertical direction Z with the positive side as the upper side and the negative side as the lower side. In the present embodiment, the vertical direction Z is the vertical direction of each drawing. In the following description, the upper side in the vertical direction is simply referred to as "upper side", and the lower side in the vertical direction is simply referred to as "lower side".

First Embodiment
As shown in FIG. 1, the drive device 1 of the present embodiment includes a rotor 20 having a housing 10 and a motor shaft 20 a disposed along a central axis J1 extending in one direction, a rotation detection unit 80, and a stator 30. And a pump portion 40, a first bearing 70, and a second bearing 71.

The central axis J1 extends in the left-right direction in FIG. That is, in the present embodiment, the left and right direction in FIG. 1 corresponds to one direction. In the following description, a direction parallel to the axial direction of the central axis J1 is simply referred to as "axial direction", a radial direction centered on the central axis J1 is simply referred to as "radial direction", and the central axis J1 is centered The circumferential direction is simply referred to as "circumferential direction". Further, the left side of FIG. 1 in the axial direction is referred to as “one side in the axial direction”, and the right side of FIG. 1 in the axial direction is referred to as the “other side in the axial direction”.

The housing 10 has a main body 11, an inner lid 12, and an outer lid 13. In the present embodiment, the main body 11, the inner lid 12 and the outer lid 13 are separate members. The main body portion 11 has a bottomed cylindrical shape that opens in one side in the axial direction. The main body portion 11 has a bottom portion 11 a, a main body cylindrical portion 11 b, and a bearing holding portion 11 c. The bottom portion 11 a is in the form of an annular plate that expands in the radial direction. The main body cylindrical portion 11b has a cylindrical shape extending in the axial direction from the outer peripheral edge portion of the bottom portion 11a. The bearing holding portion 11c has a cylindrical shape that protrudes in one axial direction from the inner edge portion of the bottom portion 11a. The bearing holder 11 c holds the second bearing 71 on the inner circumferential surface.

The inner lid 12 is attached to one side of the main body 11 in the axial direction. The inner cover 12 includes an annular plate 12a, an outer cylinder 12b, an inner cylinder 12c, an inner cylinder bottom 12d, and a bearing holder 12e. The annular plate portion 12 a has an annular plate shape that expands in the radial direction. The annular plate portion 12 a covers one axial side of the stator 30. That is, the inner cover 12 covers one side of the stator 30 in the axial direction. The lower end of the annular plate portion 12a is provided with an opening 12f which penetrates the annular plate portion 12a in the axial direction. The opening 12 f is exposed to the inside of the housing 14 described later.

The outer cylindrical portion 12b is in the shape of a cylinder extending from the radial outer edge of the annular plate portion 12a to the other side in the axial direction. The other axial end of the outer cylindrical portion 12b is fixed in contact with the axial one end of the main cylindrical portion 11b. The inner cylindrical portion 12c has a cylindrical shape extending from the radially inner edge of the annular plate portion 12a to the other side in the axial direction. The inner cylinder bottom portion 12d has an annular shape that extends radially inward from an end on the other side in the axial direction of the inner cylindrical portion 12c. The inner lid 12 is provided with a second recess 12g which is recessed from the surface on one side in the axial direction of the inner lid 12 to the other side in the axial direction by the inner cylindrical portion 12c and the inner cylinder bottom 12d. That is, the inner lid 12 has a second recess 12g. In the present embodiment, the surface on one axial side of the inner lid 12 is the surface on one axial side of the annular plate 12a. The inner side surface of the second concave portion 12g includes the radially inner side surface of the inner cylindrical portion 12c and the surface on one axial side of the inner cylindrical bottom portion 12d. In the present embodiment, the second recess 12 g corresponds to the housing recess.

The bearing holding portion 12e has a cylindrical shape that protrudes from the surface on the other side in the axial direction of the inner cylinder bottom 12d to the other side in the axial direction. The bearing holder 12e holds the first bearing 70 on the inner circumferential surface. That is, the inner lid 12 holds the first bearing 70.

The housing 10 has a housing portion 14 composed of a main body portion 11 and an inner lid portion 12. The accommodation portion 14 accommodates the rotor 20 and the stator 30 and can store oil O. The oil O is stored in the vertically lower region in the housing portion 14. In the present specification, the “vertically lower region inside the housing portion” includes a portion located below the center of the vertical direction Z inside the housing portion.

In the present embodiment, the liquid level OS of the oil O stored in the storage portion 14 is located above the opening 12 f. Thus, the opening 12 f is exposed to the oil O stored in the storage unit 14. The fluid level OS of the oil O fluctuates as the pump portion 40 sucks up the oil O, but is disposed below the rotor 20 at least when the rotor 20 rotates. Thereby, when the rotor 20 rotates, it can suppress that oil O becomes rotation resistance of the rotor 20. As shown in FIG.

The outer cover 13 is attached to one side of the inner cover 12 in the axial direction. The outer cover 13 has an outer cover main body 13a and a closing plate 13b. The outer lid main body 13a spreads in the radial direction. The outer lid main body portion 13a has a lid plate portion 13c and a projecting portion 13d. The cover plate portion 13c is in the shape of a circular plate that expands in the radial direction. The radially outer edge portion of the cover plate portion 13c is fixed to the radially outer edge portion of the annular plate portion 12a. The surface on the other side in the axial direction of the cover plate portion 13c contacts the surface on the one side in the axial direction of the annular plate portion 12a. The protrusion 13 d protrudes from the central portion of the lid plate 13 c to the other side in the axial direction. The protrusion 13 d is inserted into the inner cylindrical portion 12 c from one side in the axial direction. The protrusions 13 d are arranged at intervals on one axial side of the inner cylinder bottom 12 d.

The outer lid main body 13a has a first recess 13e and a shaft insertion hole 13f. That is, the outer cover 13 has a shaft insertion hole 13 f. The first recess 13 e is recessed from the surface on one side in the axial direction of the outer lid main body 13 a to the other side in the axial direction. The first recess 13e is provided at the center of the outer lid main body 13a, and is provided across the lid plate 13c and the protrusion 13d. The shaft insertion hole 13 f penetrates from the bottom surface of the first recess 13 e to the surface on the other side in the axial direction of the protrusion 13 d. That is, the shaft insertion hole 13 f penetrates from the bottom surface of the first recess 13 e to the inside of the housing 10. The shaft insertion hole 13f opens into the inside of the second recess 12g. Thus, the shaft insertion hole 13 f connects the inside of the first recess 13 e and the inside of the second recess 12 g. A central axis J1 passes through the shaft insertion hole 13f.

The closing plate portion 13 b has a plate shape whose plate surface is orthogonal to the axial direction. The closing plate 13b is fixed to the surface on one side in the axial direction of the outer lid main body 13a. The closing plate 13 b closes an opening on one side in the axial direction of the first recess 13 e. The closing plate 13b covers one axial side of the motor shaft 20a. That is, the outer cover 13 covers one side in the axial direction of the motor shaft 20a.

A pump chamber 46 is provided in the outer cover 13. The pump chamber 46 is provided axially between the surface on the other side in the axial direction of the closing plate 13 b and the bottom surface of the first recess 13 e. In the present embodiment, the surface on the other side in the axial direction of the pump chamber 46 is the bottom surface of the first recess 13 e. That is, the shaft insertion hole 13 f penetrates the outer cover 13 from the surface on the other side in the axial direction of the pump chamber 46 to the surface on the other side in the axial direction of the outer cover 13. The surface on one axial side of the pump chamber 46 is the surface on the other axial side of the closing plate 13 b. The inside of the pump chamber 46 is the entire inside of the first recess 13 e. The portion on the other axial direction side of the pump chamber 46 is disposed radially inward of the inner cylindrical portion 12c, that is, inside the second recess 12g. A central axis J1 passes through the pump chamber 46. As shown in FIG. 2, when viewed in the axial direction, the outer shape of the pump chamber 46 is circular. The pump chamber 46 accommodates an internal gear 43 and an external gear 42 described later.

As shown in FIG. 3, the outer cover 13 has a support 13h. The support portion 13 h is a portion of the protrusion 13 d located on the other side in the axial direction of the first recess 13 e. The support portion 13 h has an annular shape surrounding the radially outer side of the motor shaft 20 a. In the present embodiment, the support portion 13 h has an annular shape centered on the central axis J 1. The radially inner side surface of the support portion 13 h is the radially inner side surface of the shaft insertion hole 13 f. That is, the support portion 13h constitutes at least a part of the radially inner side surface of the shaft insertion hole 13f. The surface on one side in the axial direction of the support portion 13 h is the bottom surface of the first recess 13 e, and is the surface on the other side in the axial direction of the pump chamber 46. That is, the support portion 13 h constitutes at least a part of the other surface of the pump chamber 46 in the axial direction. In the present embodiment, the support portion 13 h is a part of the outer lid main body portion 13 a which is a single member.

The housing 10 has a first oil passage 61 and a third oil passage 63. The first oil passage 61 is provided in the outer cover 13. The first oil passage 61 includes a groove 13 i which is recessed from the surface on the other axial side of the pump chamber 46 to the other axial side. The first oil passage 61 is configured such that a part of an opening on one axial side of the groove 13i is closed by the external gear 42 and the internal gear 43. The first oil passage 61 is disposed inside the second recess 12 g. The first oil passage 61 extends in the radial direction. In FIG. 3, the first oil passage 61 extends downward from the upper end of the other surface of the pump chamber 46 in the axial direction, and opens in the shaft insertion hole 1 f. As a result, the radially inner end of the first oil passage 61, that is, the lower end of the first oil passage 61 in the present embodiment opens to the shaft insertion hole 13f.

The first oil passage 61 communicates with the upper portion of the pump chamber 46 on the other axial side of the pump chamber 46. The portion of the pump chamber 46 connected to the first oil passage 61 is a discharge port 45. That is, the first oil passage 61 is connected to the discharge port 45. As shown in FIG. 2, the discharge port 45 is, for example, circular.

As shown in FIG. 1, the third oil passage 63 extends upward from the opening 12 f. The third oil passage 63 is connected to the vertically lower region in the housing portion 14 via the opening 12 f. The upper end portion of the third oil passage 63 is connected to the pump chamber 46 on the other side in the axial direction of the pump chamber 46. The portion where the third oil passage 63 in the pump chamber 46 is connected is the suction port 44. That is, the third oil passage 63 connects the vertically lower region in the inside of the housing portion 14 and the suction port 44. As shown in FIG. 2, the suction port 44 is, for example, circular. The suction port 44 is disposed below the discharge port 45. The suction port 44 is disposed below the central axis J1.

As shown in FIG. 1, the third oil passage 63 has a first portion 63a, a second portion 63b, and a third portion 63c. The first portion 63a extends upward from the opening 12f. The upper end portion of the first portion 63a is located above the inner peripheral surface of the lower end portion of the inner cylindrical portion 12c. In the first portion 63a, for example, a groove extending from the surface on the other side in the axial direction of the lid plate portion 13c to one side in the axial direction and extending in the vertical direction Z is closed by a surface on one side in the axial direction of the annular plate portion 12a Configured Thus, the first portion 63 a is disposed between the inner lid 12 and the outer lid 13 in the axial direction.

The second portion 63 b extends from the upper end of the first portion 63 a to the other side in the axial direction. The second portion 63b is configured such that a groove extending upward from the lower surface of the protrusion 13d and extending to the other side in the axial direction is closed by the inner circumferential surface of the inner cylindrical portion 12c. Thus, the second portion 63 b is disposed between the inner lid 12 and the outer lid 13 in the radial direction.

The third portion 63c extends upward from the other axial end of the second portion 63b. The third portion 63c is provided to the protrusion 13d. The upper end portion of the third portion 63c is provided to the support portion 13h. The third portion 63c is disposed radially inward of the inner cylindrical portion 12c. The third portion 63 c communicates with the suction port 44. According to the present embodiment, at least a part of the third oil passage 63 is disposed between the inner lid 12 and the outer lid 13 in the axial direction. Therefore, at least a part of the third oil passage 63 can be configured by the inner cover 12 and the outer cover 13 fixed to each other, and the third oil passage 63 can be easily manufactured.

The rotor 20 includes a motor shaft 20 a, a bush 53, a rotor core 22, a magnet 23, a first end plate 24, and a second end plate 25. The motor shaft 20 a has a motor shaft body 21 and a mounting member 50. The motor shaft main body 21 has a cylindrical shape extending in the axial direction. The motor shaft main body 21 has a large diameter portion 21a, a first middle diameter portion 21b, a second middle diameter portion 21c, a small diameter portion 21d, and an output portion 21e.

The large diameter portion 21 a is a portion to which the rotor core 22 is attached. A male screw portion is provided on the outer peripheral surface of the end portion on one side in the axial direction of the large diameter portion 21a. A nut 90 is tightened on the male screw portion of the large diameter portion 21a. The first middle diameter portion 21b is connected to the large diameter portion 21a on one side in the axial direction of the large diameter portion 21a. The outer diameter of the first middle diameter portion 21b is smaller than the outer diameter of the large diameter portion 21a. The other axial end of the first middle diameter portion 21 b is rotatably supported by the first bearing 70.

The second medium diameter portion 21c is connected to the large diameter portion 21a on the other side in the axial direction of the large diameter portion 21a. The outer diameter of the second middle diameter portion 21c is smaller than the outer diameter of the large diameter portion 21a. An end on one axial side of the second middle diameter portion 21 c is rotatably supported by the second bearing 71. The first bearing 70 rotatably supports the motor shaft 20 a on one side in the axial direction with respect to the rotor core 22. The second bearing 71 rotatably supports the motor shaft 20 a on the other axial side with respect to the rotor core 22. The first bearing 70 and the second bearing 71 are, for example, ball bearings.

The small diameter portion 21 d is connected to the first middle diameter portion 21 b on one side in the axial direction of the first middle diameter portion 21 b. The end on one axial side of the small diameter portion 21 d is the end on one axial side of the motor shaft body 21. The end on one axial side of the small diameter portion 21 d is disposed radially inward of the inner cylindrical portion 12 c. The outer diameter of the small diameter portion 21d is smaller than the outer diameter of the first middle diameter portion 21b. That is, the small diameter portion 21 d is a portion in which the outer diameter decreases toward one side in the axial direction.

The output portion 21 e is connected to the second middle diameter portion 21 c on the other side in the axial direction of the second middle diameter portion 21 c. The output portion 21 e is an end on the other side in the axial direction of the motor shaft main body 21. That is, the motor shaft 20a has the output portion 21e at the other end in the axial direction. The outer diameter of the output portion 21e is smaller than the outer diameter of the small diameter portion 21d. The output portion 21 e penetrates the bottom portion 11 a in the axial direction and protrudes outside the housing 10.

The motor shaft main body 21 has a flange portion 21 f. The flange portion 21 f protrudes radially outward from the outer peripheral surface of the large diameter portion 21 a. The flange portion 21 f has an annular plate shape provided along one circumference of the outer peripheral surface of the large diameter portion 21 a. The flange portion 21 f is provided at the other end of the large diameter portion 21 a in the axial direction. The motor shaft main body 21 has a hole 21 g extending from the end on one axial side of the motor shaft main body 21 to the other axial side. The hole 21 g is a bottomed hole that opens in one side in the axial direction. That is, the other axial end of the hole 21g is closed.

As shown in FIG. 3, the mounting member 50 is fixed to one side in the axial direction of the motor shaft main body 21. The mounting member 50 is fitted and fixed to the hole 21 g. The mounting member 50 is in the form of a tube that opens to the other side in the axial direction. In the present embodiment, the mounting member 50 has a cylindrical shape that is open on both sides in the axial direction centering on the central axis J1. The mounting member 50 extends to one side in the axial direction with respect to the motor shaft main body 21 and passes through the shaft insertion hole 13 f. Thereby, the motor shaft 20a is passed through the shaft insertion hole 13f.

The mounting member 50 has an insertion portion 51 and a fixing portion 52. The insertion portion 51 is a portion fitted to the hole 21 g. The insertion portion 51 is fixed to the inner peripheral surface of the end portion on one side in the axial direction of the hole portion 21g, and extends from inside the hole portion 21g to one side in the axial direction than the motor shaft main body 21. The axial direction one end of the insertion portion 51 is inserted into the shaft insertion hole 13 f. That is, at least a portion of the insertion portion 51 is inserted into the shaft insertion hole 13 f.

The fixing portion 52 is located on one side in the axial direction of the insertion portion 51. The fixing portion 52 is connected to an end portion on one side in the axial direction of the insertion portion 51. The outer diameter of the fixing portion 52 is larger than the outer diameter of the insertion portion 51 and larger than the inner diameter of the shaft insertion hole 13 f. The fixing portion 52 is an enlarged diameter portion whose outer diameter increases from the other side in the axial direction toward the one side in the axial direction. The fixing portion 52 is inserted into the pump chamber 46. The fixing portion 52 is disposed to face one axial side of the support portion 13 h. Therefore, movement of the fixing portion 52 to the other side in the axial direction can be suppressed by the support portion 13 h. Thereby, it can suppress that the motor shaft 20a remove | deviates from the external gear 42 mentioned later. Further, since the inner diameter of the shaft insertion hole 13f is smaller than the outer diameter of the fixed portion 52, the inner diameter of the shaft insertion hole 13f can be made relatively small. Thereby, it is easy to suppress that the oil O in the pump chamber 46 leaks through the shaft insertion hole 13 f.

Although illustration is omitted, a gap is provided between the fixing portion 52 and the support portion 13 h in the axial direction. Therefore, when the motor shaft 20a rotates, it can suppress that the fixing | fixed part 52 rubs with the support part 13h, and can rotate the motor shaft 20a smoothly. The inner diameter of the insertion portion 51 and the inner diameter of the fixed portion 52 are, for example, the same.

An external gear 42 described later is fixed to the mounting member 50. In the present embodiment, the external gear 42 is fixed to the radially outer surface of the fixing portion 52. More specifically, the fixing portion 52 is fitted and fixed to the fixing hole portion 42 b axially penetrating the external gear 42. That is, in the present embodiment, the portion of the motor shaft 20 a to which the external gear 42 is fixed is the fixing portion 52. As described above, according to the present embodiment, the insertion portion 51 having an outer diameter smaller than that of the fixing portion 52 is fitted in the hole 21 g, and the external gear 42 is fixed to the fixing portion 52 having an outer diameter larger than the insertion portion 51. . Therefore, the inner diameter of the hole 21g can be smaller than the inner diameter of the fixed hole 42b of the external gear 42. As a result, the inner diameter of the hole 21g can be relatively easily reduced, and the reduction in the rigidity of the motor shaft main body 21 can be suppressed.

The motor shaft 20a has a second oil passage 62 provided inside the motor shaft 20a. The second oil passage 62 is a bottomed hole extending from the end on one axial side of the motor shaft 20a to the other axial side. The second oil passage 62 opens in one axial direction. The second oil passage 62 extends from one axial end of the mounting member 50 to the other axial end of the second middle diameter portion 21 c and is provided across the mounting member 50 and the motor shaft body 21. Be The second oil passage 62 is configured such that the inside of the mounting member 50 and the hole 21 g are connected in the axial direction. That is, the radially inner side surface of the mounting member 50 constitutes a part of the radially inner side surface of the second oil passage 62.

In the present embodiment, the inner edge of the second oil passage 62 in a cross section orthogonal to the axial direction has a circular shape centered on the central axis J1. The inner diameter of the portion provided in the mounting member 50 in the second oil passage 62 is smaller than the inner diameter of the portion provided in the motor shaft main body 21 in the second oil passage 62. That is, the inner diameter of the mounting member 50 is smaller than the inner diameter of the hole 21g.

As shown in FIG. 4, the motor shaft 20a has first

oil supply holes

26a, 26b and second

oil supply holes

26c, 26d connecting the second oil passage 62 and the outer peripheral surface of the motor shaft 20a. The first

oil supply holes

26a, 26b and the second

oil supply holes

26c, 26d extend in the radial direction. The first

oil supply holes

26a, 26b are provided in the large diameter portion 21a. The first

oil supply holes

26a and 26b are disposed between the nut 90 and the flange portion 21f in the axial direction. A radially outer end of the first oil supply hole 26 a opens in an axial gap 27 a between the first end plate 24 and the rotor core 22. The radial outer end of the first oil supply hole 26 b opens in an axial gap 27 b between the second end plate 25 and the rotor core 22.

The second oil supply hole 26c is provided in the first middle diameter portion 21b. The radially outer end of the second oil supply hole 26c opens radially inward of the bearing holding portion 12e on one axial side of the first bearing 70. The second oil supply hole 26d is provided in the second middle diameter portion 21c. The radially outer end of the second oil supply hole 26 d opens radially inward of the bearing holding portion 11 c on the other axial side of the second bearing 71. For example, a plurality of the first

oil supply holes

26a and 26b and the second

oil supply holes

26c and 26d are respectively provided along the circumferential direction. In the present embodiment, the first

oil supply holes

26a, 26b correspond to first through holes.

As shown in FIG. 3, the motor shaft 20a has a connection hole 54 connecting the second oil passage 62 and the outer peripheral surface of the motor shaft 20a. In the present embodiment, the connection hole 54 is provided in the mounting member 50. More specifically, the connection hole 54 is provided at one end of the insertion portion 51 in the axial direction. The connection hole 54 penetrates radially from the inner circumferential surface of the insertion portion 51 to the outer circumferential surface of the insertion portion 51. The connection hole 54 is connected to the inside of the mounting member 50.

The connection hole portion 54 is provided in a portion of the insertion portion 51 which is inserted into the shaft insertion hole 13 f. That is, the connection hole portion 54 opens at the outer peripheral surface of the portion of the motor shaft 20a inserted into the shaft insertion hole 13f. A portion on one axial side of the inner side surface of the connection hole 54 is connected radially inward of the other axial surface of the fixing portion 52.

A clearance 15 is provided between the outer peripheral surface of the axial direction portion in which the connection hole portion 54 is provided in the insertion portion 51 and the inner side surface of the shaft insertion hole 13 f. The clearance 15 is a part of the inside of the shaft insertion hole 13 f. The clearance 15 is, for example, an annular shape centered on the central axis J1. The radial inner end of the first oil passage 61 is open in the gap 15. The radially outer end of the connection hole 54 opens in the gap 15 and is connected to the inside of the shaft insertion hole 13 f. Thus, the connection hole 54 is connected to the first oil passage 61 through the shaft insertion hole 13 f. The connection hole 54 connected to the inside of the mounting member 50 is connected to the first oil passage 61, whereby the second oil passage 62 is connected to the first oil passage 61 via the inside of the mounting member 50.

The connection hole portion 54 is disposed on one side in the axial direction with respect to the first bearing 70, the first

oil supply holes

26a and 26b, and the second

oil supply holes

26c and 26d. In the present embodiment, the first oil passage 61 and the connection hole 54 are disposed at the same position in the axial direction. The connection hole 54 is disposed inside the second recess 12 g. In the present embodiment, the connection hole 54 corresponds to a second through hole.

The bush 53 extends in the axial direction and has a cylindrical shape centered on the central axis J1. The bush 53 is fitted and fixed to the motor shaft 20a. More specifically, the bush 53 is fitted to and fixed to the insertion portion 51 from the radially outer side. The bush 53 is press-fit into the insertion portion 51, for example. At least a portion of the bush 53 is disposed between the support 13 h and the motor shaft 20 a in the radial direction. That is, at least a part of the bush 53 is inserted into the shaft insertion hole 13 f. In the present embodiment, a portion on one axial side of the bush 53 is disposed between the support portion 13 h and the insertion portion 51 in the radial direction.

The end on one axial side of the bush 53 is disposed farther to the other axial side than the end on the other axial side of the fixing portion 52. The axial direction one end of the bush 53 is exposed to the gap 15. The axial direction one end of the bush 53 is disposed on the other axial side of the first oil passage 61 and the connection hole 54. That is, the bush 53 is disposed between the inner side surface of the shaft insertion hole 13 f and the outer peripheral surface of the motor shaft 20 a on the other side in the axial direction than the first oil passage 61. The other axial end of the bush 53 projects on the other axial side with respect to the support 13 h. A gap is provided between the other end of the bush 53 in the axial direction and the one end of the motor shaft main body 21 in the axial direction. In the present embodiment, the bush 53 is a wedge member that blocks at least a part of the oil O flowing into the shaft insertion hole 13 f from the first oil passage 61.

In the present embodiment, the motor shaft 20a is rotatably supported by the support 13h via the bush 53. More specifically, the motor shaft 20a is rotatably supported on the inner surface of the shaft insertion hole 13f via the bush 53. That is, the support portion 13 h rotatably supports the motor shaft 20 a on the radially outer side of the motor shaft 20 a. In the present embodiment, the support portion 13 h rotatably supports the mounting member 50. More specifically, the insertion portion 51 of the support portion 13 h is rotatably supported.

In the present specification, “the support portion rotatably supports the motor shaft” means that the support portion suppresses the radial movement of the motor shaft while the motor shaft can rotate around the central axis J1, and It includes rotating the motor shaft directly or indirectly while sliding relative to the radially inner end of the support. “The motor shaft indirectly rotates while sliding relative to the radially inner end of the support portion” means that a member fixed to the outer peripheral surface of the motor shaft slides relative to the radially inner end of the support portion Including rotating. In the present embodiment, the outer peripheral surface of the bush 53 fixed to the motor shaft 20a rotates while sliding with respect to the radial inner end portion of the support portion 13h. The radially inner end portion of the support portion 13 h is an inner peripheral surface of the shaft insertion hole 13 f.

As shown in FIG. 1, the rotor core 22 is annular and fixed to the motor shaft body 21. In the present embodiment, the rotor core 22 is fitted to the large diameter portion 21 a. The rotor core 22 has a magnet insertion hole 22 b which penetrates the rotor core 22 in the axial direction. A plurality of magnet insertion holes 22 b are provided along the circumferential direction. The magnet 23 is inserted into the magnet insertion hole 22b.

The first end plate 24 and the second end plate 25 are in the form of a radially expanding annular plate. The large diameter portion 21 a is passed through the first end plate 24 and the second end plate 25. The first end plate 24 and the second end plate 25 sandwich the rotor core 22 in the axial direction in contact with the rotor core 22.

As shown in FIG. 4, the first end plate 24 is disposed on one side in the axial direction of the rotor core 22. The radially outer edge portion of the first end plate 24 protrudes to the other side in the axial direction, and is in contact with the radially outer edge portion of the surface on one axial side of the rotor core 22. The radially outer edge portion of the first end plate 24 axially overlaps the opening on one axial side of the magnet insertion hole 22b, and presses the magnet 23 inserted in the magnet insertion hole 22b from one axial side. A portion radially inward of the radially outer edge portion of the first end plate 24 opposes the surface on one axial side of the rotor core 22 in the axial direction with a gap 27 a therebetween.

The first end plate 24 has a jet groove 24 a recessed from the surface on one axial side of the first end plate 24 to the other axial side. The ejection grooves 24 a extend in the radial direction. The radially inner end of the ejection groove 24a penetrates the first end plate 24 in the axial direction and is connected to the gap 27a. The radially outer end of the ejection groove 24 a opens radially outward of the first end plate 24 and radially opposes a coil 32 described later with a gap therebetween. Thereby, the first oil supply hole 26a is connected to the inside of the housing portion 14 via the gap 27a and the ejection groove 24a. The opening on one axial side of the radially inner portion of the ejection groove 24 a is closed by a washer 91 which is sandwiched and fixed between the nut 90 and the first end plate 24 in the axial direction. The washer 91 is in the form of an annular plate that expands in the radial direction.

The second end plate 25 is disposed on the other side of the rotor core 22 in the axial direction. The radially outer edge portion of the second end plate 25 protrudes to one side in the axial direction, and contacts the radially outer edge portion of the surface on the other side in the axial direction of the rotor core 22. The radially outer edge portion of the second end plate 25 axially overlaps the opening on the other side in the axial direction of the magnet insertion hole 22b, and presses the magnet 23 inserted in the magnet insertion hole 22b from the other side in the axial direction. Thereby, the magnet 23 inserted into the magnet insertion hole 22 b is pressed by the first end plate 24 and the second end plate 25 on both sides in the axial direction. Therefore, it can suppress that the magnet 23 slips out of the magnet insertion hole 22b.

A portion radially inward of the radially outer edge portion of the second end plate 25 opposes the other axial surface of the rotor core 22 in the axial direction via the gap 27 b. The second end plate 25 has a jet groove 25 a which is recessed from the surface on the other side in the axial direction of the second end plate 25 to the one side in the axial direction. The ejection groove 25a extends in the radial direction. The radially inner end of the ejection groove 25a penetrates the second end plate 25 in the axial direction and is connected to the gap 27b. The radially outer end of the ejection groove 25a opens radially outward of the second end plate 25, and is opposed to the coil 32 described later via a gap in the radial direction. Thus, the first oil supply hole 26b is connected to the inside of the housing portion 14 through the gap 27b and the ejection groove 25a. The opening on the other axial direction side of the radially inner portion of the ejection groove 25a is closed by the flange portion 21f.

The first end plate 24, the rotor core 22 and the second end plate 25 are axially held by the nut 90, the washer 91 and the flange portion 21f. As the nut 90 is tightened on the male screw portion of the large diameter portion 21a, the nut 90 presses the first end plate 24, the rotor core 22 and the second end plate 25 against the flange portion 21f via the washer 91. As a result, the first end plate 24, the rotor core 22 and the second end plate 25 are fixed to the motor shaft 20a.

A rotation detection unit 80 illustrated in FIG. 1 detects the rotation of the rotor 20. In the present embodiment, the rotation detection unit 80 is, for example, a VR (Variable Reluctance) resolver. The rotation detection unit 80 is disposed on the inner side in the radial direction of the inner cylindrical portion 12c. The rotation detection unit 80 has a detected unit 81 and a sensor unit 82.

The to-be-detected part 81 is an annular shape extended in the circumferential direction. The to-be-detected part 81 is fitted and fixed to the motor shaft 20a. More specifically, the detection portion 81 is fitted and fixed to the small diameter portion 21d. The surface on the other axial direction side of the radially inner edge portion of the detection target portion 81 contacts a step between the first middle diameter portion 21 b and the small diameter portion 21 d. The to-be-detected part 81 overlaps the attachment member 50 in the radial direction. Therefore, it is easier to miniaturize the motor shaft 20a in the axial direction, as compared to the case where the detection target portion 81 and the mounting member 50 are disposed apart in the axial direction without overlapping in the radial direction. The to-be-detected part 81 is made of a magnetic material.

In the present specification, "overlapping certain objects in a certain direction" includes overlapping certain objects when viewed along a certain direction. That is, overlapping the detection target portion 81 and the attachment member 50 in the radial direction means that the detection target portion 81 and the attachment member 50 overlap when viewed along the radial direction.

The sensor unit 82 is disposed between the inner lid 12 and the outer lid 13 in the axial direction. More specifically, the sensor portion 82 is fixed to the surface on one side in the axial direction of the inner cylinder bottom portion 12 d at the inner side in the radial direction of the inner cylinder portion 12 c. That is, the sensor unit 82 is attached to the inner lid 12. Therefore, the sensor unit 82 can be easily attached. The sensor unit 82 is disposed in the second recess 12 g. Therefore, after the inner lid portion 12 is attached to the main body portion 11, the sensor portion 82 can be inserted and disposed in the second recess 12g from the opening on one side in the axial direction of the second recess 12g. Therefore, it is easy to arrange the sensor unit 82.

The sensor unit 82 has an annular shape surrounding the outside in the radial direction of the detection target 81. The sensor unit 82 has a plurality of coils along the circumferential direction. When the detected portion 81 rotates with the motor shaft 20a, an induced voltage is generated in the coil of the sensor portion 82 according to the circumferential direction position of the detected portion 81. The sensor unit 82 detects rotation of the detection target unit 81 by detecting the induced voltage. Thus, the rotation detection unit 80 detects the rotation of the motor shaft 20 a and detects the rotation of the rotor 20.

The stator 30 faces the rotor 20 in the radial direction via a gap. The stator 30 has a stator core 31 and a plurality of coils 32 mounted on the stator core 31. The stator core 31 has an annular shape centered on the central axis J1. The outer peripheral surface of the stator core 31 is fixed to the inner peripheral surface of the main body cylindrical portion 11b. The stator core 31 faces the radially outer side of the rotor core 22 via a gap.

The pump unit 40 is provided at the center of the outer cover 13. The pump portion 40 is disposed on one side in the axial direction of the motor shaft 20a. The pump unit 40 has an external gear 42, an internal gear 43, the pump chamber 46 described above, an inlet 44, and an outlet 45. The external gear 42 is a gear that can rotate around the central axis J1. The external gear 42 is fixed to one end of the motor shaft 20 a in the axial direction. More specifically, the external gear 42 is fixed to the outer peripheral surface of the fixing portion 52. Therefore, the external gear 42 can be fixed to the motor shaft main body 21 via the mounting member 50. Thus, by adjusting the dimensions of the mounting member 50, the external gear 42 can be fixed to the motor shaft main body 21 without changing the dimensions of the motor shaft main body 21 and the external gear 42.

The external gear 42 is accommodated in the pump chamber 46. As shown in FIG. 2, the external gear 42 has a plurality of teeth 42 a on the outer peripheral surface. The tooth profile of the tooth portion 42a of the external gear 42 is a trochoidal tooth profile.

The internal gear 43 is an annular gear that can rotate around a rotation axis J2 that is eccentric with respect to the central axis J1. The internal gear 43 is accommodated in the pump chamber 46. The internal gear 43 surrounds the radially outer side of the external gear 42 and meshes with the external gear 42. The internal gear 43 has a plurality of teeth 43a on the inner peripheral surface. The tooth form of the tooth portion 43a of the internal gear 43 is a trochoidal tooth form. Thus, since the tooth shape of the tooth portion 42a of the external gear 42 and the tooth shape of the tooth portion 43a of the internal gear 43 are trochoidal teeth, a trochoid pump can be configured. Therefore, the noise generated from the pump unit 40 can be reduced, and the pressure and the amount of the oil O discharged from the pump unit 40 can be easily stabilized.

In the present embodiment, after the internal gear 43 and the external gear 42 are inserted from the opening on one axial side of the first recess 13 e, the opening on the axial one side of the first recess 13 e is closed by the closing plate 13 b. Thus, the pump chamber 46 can be configured, and the internal gear 43 and the external gear 42 can be accommodated in the pump chamber 46. Therefore, the assembly of the pump unit 40 can be facilitated.

As described above, the suction port 44 is connected to the third oil passage 63. As shown in FIG. 1, the suction port 44 opens to the other axial side of the pump chamber 46. The suction port 44 is connected to the gap between the external gear 42 and the internal gear 43. The suction port 44 receives the oil O stored in the housing portion 14 through the opening 12 f and the third oil passage 63 in the pump chamber 46, more specifically, the gap between the external gear 42 and the internal gear 43. It can be inhaled. As shown in FIG. 2, the suction port 44 is disposed above the lower end of the external gear 42.

As described above, the discharge port 45 is connected to the first oil passage 61. As shown in FIG. 1, the discharge port 45 opens on one side in the axial direction of the pump chamber 46. The discharge port 45 is connected to the gap between the external gear 42 and the internal gear 43. The discharge port 45 can discharge the oil O from the inside of the pump chamber 46, more specifically, from the gap between the external gear 42 and the internal gear 43.

When the rotor 20 rotates and the motor shaft 20a rotates, the external gear 42 fixed to the motor shaft 20a rotates. As a result, the internal gear 43 meshing with the external gear 42 rotates, and the oil O sucked into the pump chamber 46 from the suction port 44 passes between the external gear 42 and the internal gear 43, It is sent to the discharge port 45. Thus, the pump unit 40 is driven via the motor shaft 20a. The oil O discharged from the discharge port 45 flows into the first oil passage 61, and as shown by the arrow in FIG. 3, the second oil passage 62 from the connection hole 54 through the clearance 15 in the inside of the shaft insertion hole 13f. Flow into Thus, the oil O flows into the second oil passage 62 from the outer side in the radial direction.

Note that, in FIG. 3, an example in which the connection hole portion 54 opens upward and the oil O flowing into the gap 15 from the first oil passage 61 flows downward as it is and flows into the connection hole portion 54 is indicated by arrows. Not limited to this. Since the motor shaft 20a rotates around the central axis J1, the opening position of the connection hole 54 changes in the circumferential direction as the motor shaft 20a rotates. However, since the gap 15 is annular, the connection hole 54 opens into the gap 15 even when the opening position of the connection hole 54 is at any position in the circumferential direction. Therefore, regardless of the rotational position of the motor shaft 20 a in the circumferential direction, the oil O can flow from the gap 15 into the connection hole 54.

As indicated by an arrow in FIG. 4, the oil O flowing into the second oil passage 62 from the connection hole 54 flows to the other side in the axial direction. The oil O receives a force radially outward due to the centrifugal force of the rotating motor shaft 20a, and passes through the first

oil supply holes

26a, 26b and the second

oil supply holes

26c, 26d to the outside of the motor shaft 20a. And flow out.

In the present embodiment, since the first oil supply hole 26a opens in the axial gap 27a between the first end plate 24 and the rotor core 22, the oil O flowing out of the first oil supply hole 26a flows into the gap 27a. Then, the oil O that has flowed into the gap 27a is jetted radially outward from the jetting groove 24a. In the present embodiment, the opening on one axial direction side of the radially inner portion of the ejection groove 24a is closed by the washer 91, so the oil O introduced into the ejection groove 24a is directed radially outward by the washer 91 It's easy to do.

Since the first oil supply hole 26 b opens in the axial gap 27 b between the second end plate 25 and the rotor core 22, the oil O flowing out of the first oil supply hole 26 b flows into the gap 27 b. Then, the oil O that has flowed into the gap 27 b is ejected radially outward from the ejection groove 25 a. In the present embodiment, the opening on the other axial direction side of the radially inner portion of the ejection groove 25a is closed by the flange portion 21f, so the oil O flowing into the ejection groove 25a is directed radially outward by the flange portion 21f. Easy to guide.

The oil O ejected radially outward from the

ejection grooves

24 a and 25 a is sprayed to the coil 32. Thereby, the coil 32 can be cooled by the oil O. In the present embodiment, since the second oil passage 62 is provided inside the motor shaft 20a, the rotor 20 can also be cooled by the oil O until it is ejected from the

ejection grooves

24a, 25a. Thus, the oil O discharged from the discharge port 45 in the present embodiment is led to the rotor 20 and the stator 30.

The second oil supply hole 26 c is opened inward in the radial direction of the bearing holding portion 12 e, so the oil O flowing out of the second oil supply hole 26 c is supplied to the first bearing 70. Since the second oil supply hole 26 d is opened inward in the radial direction of the bearing holding portion 11 c, the oil O that has flowed out from the second oil supply hole 26 d is supplied to the second bearing 71. Thus, the oil O can be used as a lubricant for the first bearing 70 and the second bearing 71.

Although FIG. 4 shows an example in which the oil O is ejected upward from the

ejection grooves

24a and 25a, the invention is not limited thereto. Since the rotor 20 rotates, the circumferential position of the

ejection grooves

24 a and 25 a changes as the rotor 20 rotates. Thus, the direction of the oil O ejected from the

ejection grooves

24 a and 25 a changes in the circumferential direction, and the plurality of coils 32 disposed along the circumferential direction can be cooled by the oil O.

As described above, the pump unit 40 can be driven by the rotation of the motor shaft 20a, and the pump unit 40 sucks up the oil O stored in the housing 10 to collect the rotor 20, the stator 30, the first bearing 70 and the second The bearing 71 can be supplied. Thereby, the oil 20 stored in the housing 10 can be used to cool the rotor 20 and the stator 30, and the lubricity between the first bearing 70 and the second bearing 71 and the motor shaft body 21 can be reduced. It can improve. The oil O supplied to the stator 30, the first bearing 70 and the second bearing 71 drops in the housing portion 14 and is stored again in the lower region in the housing portion 14. Thereby, the oil O in the accommodating part 14 can be circulated.

According to the present embodiment, since the oil O can flow into the second oil passage 62 of the motor shaft 20a from the outside in the radial direction via the connection hole portion 54, the drive device 1 can be easily miniaturized in the axial direction. In addition, since the first oil passage 61 can be formed by utilizing the groove 13i provided on the other surface of the pump chamber 46 in the axial direction, the drive is performed compared to the case where the first oil passage is provided outside the pump chamber 46. It is easy to miniaturize the device 1 in the axial direction. Therefore, according to this embodiment, the drive device 1 having a structure that can be miniaturized in the axial direction can be obtained.

Further, according to the present embodiment, the support portion 13h rotatably supports the motor shaft 20a on the radially outer side of the motor shaft 20a, and at least a part of the surface on the other side in the axial direction of the pump chamber 46 and the shaft insertion hole It constitutes at least a part of the radially inner surface of 13 f. Thereby, the motor shaft 20 a can be supported in the vicinity of the pump chamber 46. Therefore, even when the coaxial accuracy between the rotor 20 and the stator 30 is relatively low, the motor shaft 20a can be prevented from being inclined with respect to the pump portion 40, and the motor shaft 20a can be axially corrected with respect to the pump portion 40. It can be arranged well. Thus, in the pump chamber 46, the external gear 42 fixed to the motor shaft 20a can be prevented from being displaced relative to the internal gear 43. Therefore, it can suppress that the external gear 42 is strongly pressed against the internal gear 43, and can suppress abrasion of the external gear 42 and the internal gear 43. As described above, according to the present embodiment, the drive device 1 capable of suppressing damage to the pump unit 40 can be obtained.

Further, according to the present embodiment, since the support portion 13h constitutes at least a part of the surface on the other side in the axial direction of the pump chamber 46 and at least a part of the radially inner side surface of the shaft insertion hole 13f, the first oil passage The oil O which has flowed from 61 into the gap 15 of the shaft insertion hole 13f can be supplied between the support portion 13h and the motor shaft 20a in the radial direction. Thus, the oil O can be used as a lubricant, and the motor shaft 20a supported by the support 13h can be smoothly rotated.

In the present embodiment, at least a part of the bush 53 fixed to the motor shaft 20a is disposed between the support portion 13h and the motor shaft 20a in the radial direction. Therefore, the motor shaft 20a supported by the support portion 13h can be rotated more smoothly by the bush 53. Furthermore, the oil O that has flowed into the gap 15 of the first oil passage 61 can also be supplied between the support portion 13 h and the bush 53 in the radial direction. Therefore, the bush 53 can be made more slippery with respect to the support portion 13h, and the motor shaft 20a can be rotated more smoothly.

Further, according to the present embodiment, the support portion 13 h is an annular shape that surrounds the radially outer side of the motor shaft 20 a. Therefore, the entire circumference of the motor shaft 20a can be supported by the support portion 13h, and the motor shaft 20a can be supported more stably.

Further, according to the present embodiment, the support portion 13 h rotatably supports the attachment member 50. Therefore, regardless of the outer diameter of the motor shaft main body 21, the outer diameter of the portion of the motor shaft 20a supported by the support portion 13h can be reduced. Thus, the inner diameter of the shaft insertion hole 13f can be easily reduced, and the amount of the oil O leaking to the outside of the shaft insertion hole 13f is reduced while the oil O is supplied between the support portion 13h and the motor shaft 20a in the radial direction. it can. When the bush 53 is provided as in the present embodiment, the bush 53 may be fixed to the mounting member 50, and the bush 53 can be easily attached.

Further, according to the present embodiment, the bush 53 functions as a wedge member for blocking at least a part of the oil O flowing from the first oil passage 61 into the shaft insertion hole 13 f. Therefore, it is possible to further suppress the leakage of the oil O flowing from the first oil passage 61 into the shaft insertion hole 13 f to the outside of the shaft insertion hole 13 f. Therefore, reduction in the amount of oil O flowing from the first oil passage 61 into the second oil passage 62 can be suppressed. Further, since the wedge member is the bush 53, it is not necessary to separately provide the bush 53 and the wedge member, and an increase in the number of parts of the drive device 1 can be suppressed.

Further, according to the present embodiment, the first oil passage 61 and the connection hole 54 are disposed at the same position in the axial direction. Therefore, the oil O flowing from the first oil passage 61 into the gap 15 can be easily introduced into the connection hole 54. Thus, the oil O can easily flow from the first oil passage 61 to the second oil passage 62 via the connection hole 54.

Further, according to the present embodiment, the connection hole 54 is provided in the attachment member 50. Therefore, by replacing the mounting member 50, the position etc. of the connection hole 54 can be easily changed. Therefore, the connection hole 54 can be easily changed to a suitable configuration in accordance with the design change or the like of the pump chamber 46 and the first oil passage 61.

Further, according to the present embodiment, the connection hole portion 54 is provided at an end portion on one side in the axial direction of the insertion portion 51. Therefore, the axial position of the connection hole 54 can be made closer to the fixed portion 52 inserted into the pump chamber 46. Accordingly, it is easy to make the axial position of the connection hole 54 the same as the axial position of the first oil passage 61 provided on the other surface of the pump chamber 46 in the axial direction. Therefore, it is easy to flow the oil O from the first oil passage 61 to the second oil passage 62 via the connection hole 54. Further, since the oil O can be guided to the connection hole 54 along the surface on the other side in the axial direction of the fixed portion 52, the oil O can easily flow from the first oil passage 61 to the connection hole 54.

Further, according to the present embodiment, the connection hole 54 is provided in the portion of the motor shaft 20a opposite to the output portion 21e in the axial direction, and the connection hole 54 is on one side in the axial direction with respect to the first bearing 70. Be placed. Therefore, in the case where the motor shaft 20a is configured to include the motor shaft main body 21 and the attachment member 50 which are separate members, the motor shaft main body 21 is supported by the first bearing 70 and on one axial side of the motor shaft main body 21. The connection hole 54 can be provided in the mounting member 50 to be fixed. Further, the output portion 21 e can be provided on the motor shaft main body 21. Therefore, the structure which provides the connection hole 54 in the attachment member 50 can be employ | adopted, stably supporting the motor shaft main body 21 which has the output part 21e by the 1st bearing 70. FIG.

Further, according to the present embodiment, the detection target portion 81, the sensor portion 82, the first oil passage 61, and the connection hole portion 54 are disposed inside the second concave portion 12g. Therefore, the first oil passage 61 and the connection hole 54 can be disposed using the space in which the rotation detection unit 80 is disposed, and the drive device 1 can be easily miniaturized in the axial direction.

Further, according to the present embodiment, the oil O discharged from the discharge port 45 can be sent to the inside of the motor shaft 20a by providing the first oil passage 61 and the second oil passage 62. Further, since the first

oil supply holes

26a and 26b and the second

oil supply holes

26c and 26d are provided, the oil O flowing into the second oil passage 62 is supplied to the stator 30, the first bearing 70 and the second bearing 71. can do.

Further, according to the present embodiment, the second oil passage 62 is configured such that the inside of the mounting member 50 and the hole 21 g are connected in the axial direction, and is connected to the first oil passage 61 via the inside of the mounting member 50. . Therefore, the oil O can be made to flow from the mounting member 50 into the second oil passage 62 while fixing the external gear 42 to the mounting member 50. Thereby, as described above, the motor shaft body 21 and the external gear 42 can be fixed via the mounting member 50 without changing the dimensions of the motor shaft body 21 and the external gear 42, and the second oil The passage 62 can be easily opened to the first oil passage 61.

The present invention is not limited to the above-described embodiment, and other configurations can be adopted. The weir member is not particularly limited as long as it can block at least a part of the oil O flowing from the first oil passage 61 into the shaft insertion hole 13f, and may not be a bush. The wedge member may be configured, for example, like the wedge member 153 shown in FIG. As shown in FIG. 5, the wedge member 153 is a resin member fixed to the outer peripheral surface of the fitting portion 151 of the mounting member 150. The wedge member 153 has, for example, an annular shape centered on the central axis J1.

The radially inner edge portion of the wedge member 153 is disposed in the third recess 151 a that is recessed inward in the radial direction from the outer peripheral surface of the fitting portion 151. The third recess 151a is, for example, an annular shape centered on the central axis J1. The radially outer edge portion of the wedge member 153 protrudes radially outward from the fitting portion 151. In the cross section orthogonal to the circumferential direction, the outer shape of the radially outer edge portion of the wedge member 153 has an arc shape which is convex outward in the radial direction. A plurality of wedge members 153 may be provided, for example, at intervals along the circumferential direction. Moreover, the wedge member may not be provided.

The connection hole 54 may be disposed at a position different from the first oil passage 61 in the axial direction. A plurality of connection holes 54 may be provided along the circumferential direction. The first oil passage 61 is not particularly limited as long as it is connected to the discharge port 45 and opens in the shaft insertion hole 13 f. The first oil passage 61 may be linear or curved.

The support portion 13 h may not be annular. For example, a plurality of support portions 13 h may be provided at intervals along the circumferential direction. Further, the shape of the support portion 13h is not particularly limited as long as the motor shaft 20a can be rotatably supported. The support 13 h may be provided on the outer lid 13 as a separate member. The bush 53 may be disposed between the support 13 h and the motor shaft 20 a in the radial direction. The bush 53 may not be provided.

The external gear 42 may be directly fixed to the motor shaft body 21 without the attachment member 50. In this case, the second oil passage 62 may be provided, for example, only inside the motor shaft body 21. Further, the mounting member 50 may be fixed to the outer peripheral surface of the motor shaft main body 21.

Further, the mounting member 50 may be a member having a uniform outer diameter throughout the axial direction. That is, the outer diameter of the insertion portion 51 and the outer diameter of the fixed portion 52 may be the same as each other. In this case, for example, if the outer diameter of the fixing portion 52 is made the same as the outer diameter of the inserting portion 51 shown in FIG. 1 and made smaller, it is possible to reduce the outer diameter of the external gear 42 to which the fixing portion 52 is fixed. . Thereby, the outer diameter of the internal gear 43 can be reduced, and the inner diameter of the pump chamber 46 can be reduced. Therefore, the outer diameter of the projecting portion 13d provided with the pump chamber 46 can be reduced, and the radial direction between the radially outer surface of the projecting portion 13d and the inner circumferential surface of the second recess 12g can be enlarged. Therefore, it is possible to arrange, for example, a portion of the sensor portion 82 that protrudes to one side in the axial direction between the radial outer surface of the protrusion 13 d and the inner circumferential surface of the second recess 12 g. Thus, the sensor unit 82 can be brought closer to the outer cover 13. Thereby, it is easy to miniaturize the entire drive device 1 in the axial direction. In addition, the part which protrudes in the axial direction one side among sensor parts 82 is a coil which sensor part 82 has, for example.

Also, the mounting member 50 may be configured by two or more members. In this case, the mounting member 50 includes a first cylindrical member fitted in the hole 21g, and a second cylindrical member fitted on the first cylindrical member and extending on one side in the axial direction with respect to the motor shaft main body 21. , May be included. In this case, the external gear 42 is fixed to an end of the second cylindrical member on one side in the axial direction. Further, the mounting member 50 may have a tubular shape that opens only to the other side in the axial direction. Also, the motor shaft 20a may have a single member without the mounting member 50.

The rotor core 22 may be fixed to the outer peripheral surface of the motor shaft main body 21 by press fitting or the like. In this case, the first end plate 24 and the second end plate 25 may not be provided. Further, in this case, the oil O flowing out of the first

oil supply holes

26a, 26b may be directly supplied to the coil 32, or holes connected to the first

oil supply holes

26a, 26b are provided in the rotor core 22; Oil O may be supplied to the coil 32 through the hole of the rotor core 22. Also, the oil O may be supplied to the stator core 31.

Moreover, the location to which the oil O discharged from the discharge port 45 is supplied is not specifically limited, For example, it is supplied only to any one or two of the stator 30, the 1st bearing 70, and the 2nd bearing 71 It may or may not be supplied. The oil O discharged from the discharge port 45 may be supplied to, for example, the inner side surface of the vertically upper region of the storage unit 14. In this case, cooling the housing 10 can indirectly cool the stator 30. The number of the first

oil supply holes

26a and 26b and the number of the second

oil supply holes

26c and 26d may be one or three or more, respectively. The second

oil supply holes

26c and 26d may not be provided. The tooth shape of the tooth portion 42a of the external gear 42 and the tooth shape of the tooth portion 43a of the internal gear 43 may be a cycloid tooth shape or an involute tooth shape.

Second Embodiment
FIG. 6 is a cross-sectional view showing a part of the drive device of the second embodiment. With reference to FIG. 6, in the outer cover 213 of the drive device 201 of the present embodiment, the first recess 213e of the outer cover main body 213a is axially one side from the surface of the outer cover main body 213a on the other axial side Sink in. The closing plate portion 213b is fixed to the other surface of the outer lid main body portion 213a in the axial direction. The opening on the other side in the axial direction of the first recess 213 e is closed by the closing plate portion 213 b, and the pump chamber 246 is provided. The surface on one axial side of the pump chamber 246 is the bottom surface of the first recess 213e. The surface on the other side in the axial direction of the pump chamber 246 is the surface on the one side in the axial direction of the closing plate portion 213b.

The closing plate portion 213b has a shaft insertion hole 213f which penetrates the closing plate portion 213b in the axial direction. The lower end portion of the closing plate portion 213b is axially pinched in a state of being in contact with the outer lid main body portion 213a and the annular plate portion 12a. An axial gap 216 between the inner lid 12 and the outer lid 213 is provided below the closing plate 213 b. The gap 216 is connected to the vertically lower region in the housing portion 14 through the opening 12 f.

In the present embodiment, the first oil passage 261 includes a groove 213i which is recessed from the surface on one side in the axial direction of the closing plate portion 213b to the other side in the axial direction. The first oil passage 261 is configured such that a part of the opening on one axial side of the groove 213i is closed by the external gear 42 and the internal gear 43.

In the present embodiment, the third oil passage 263 is disposed between the outer lid main body portion 213a and the closing plate portion 213b in the axial direction. The third oil passage 263 is configured such that an opening on one axial side of a groove recessed from the surface on one axial side of the closing plate 213 b to the other axial side is closed by the outer cover main body 213 a. As described above, according to the present embodiment, since both the first oil passage 261 and the third oil passage 263 can be provided in the outer lid portion 213, it is easy to provide each oil passage.

The third oil passage 263 extends in the vertical direction Z. The lower end of the third oil passage 263 opens into the gap 216. The third oil passage 263 is connected to the opening 12 f via the gap 216. As a result, the oil O in the housing portion 14 flows from the opening 12 f into the third oil passage 263 via the gap 216.

In addition, the application of the drive device of embodiment mentioned above is not specifically limited. The drive device of the embodiment described above is mounted on, for example, a vehicle. Moreover, each structure mentioned above can be combined suitably in the range which does not contradiction mutually.

Claims

A rotor having a motor shaft disposed along a central axis extending in one direction and a rotor core fixed to the motor shaft;
A stator that faces the rotor in the radial direction via a gap;
A housing that accommodates the rotor and the stator and has an accommodation portion capable of storing oil;
A pump unit driven via the motor shaft;
Equipped with
The pump unit is
An external gear fixed to one axial end of the motor shaft;
An internal gear that surrounds the radially outer side of the external gear and meshes with the external gear;
A pump chamber for accommodating the internal gear and the external gear;
A suction port capable of sucking oil into the pump chamber;
A discharge port capable of discharging oil from the pump chamber;
Have
The housing is
An outer lid portion provided with the pump chamber and covering one axial side of the motor shaft;
A first oil passage provided in the outer lid and connected to the discharge port;
Have
The outer cover portion has a shaft insertion hole through which the motor shaft is passed, the outer cover portion penetrating from the surface on the other side in the axial direction of the pump chamber to the surface on the other side in the axial direction of the outer cover ,
The motor shaft is
A second oil passage provided inside the motor shaft and connected to the first oil passage;
A first through hole connecting the second oil passage and the outer peripheral surface of the motor shaft;
A second through hole disposed on one side in the axial direction of the first through hole and connecting the second oil passage and the outer peripheral surface of the motor shaft;
Have
The first through hole is connected to the inside of the housing portion,
The first oil passage includes a groove recessed from the surface on the other side in the axial direction of the pump chamber to the other side in the axial direction,
The radially inner end of the first oil passage opens into the shaft insertion hole,
The second through hole is open at an outer peripheral surface of a portion of the motor shaft inserted into the shaft insertion hole, and is connected to the first oil passage through the shaft insertion hole.
It further comprises a wedge member disposed radially between the inner surface of the shaft insertion hole and the outer peripheral surface of the motor shaft on the other axial side with respect to the first oil passage,
The drive device according to claim 1, wherein the weir member blocks at least a part of the oil flowing from the first oil passage into the shaft insertion hole.
The wedge member is a cylindrical bush fitted and fixed to the motor shaft,
The drive device according to claim 2, wherein the motor shaft is rotatably supported on the inner surface of the shaft insertion hole via the wedge member.
The drive device according to any one of claims 1 to 3, wherein the first oil passage and the second through hole are arranged at the same position in the axial direction.
The motor shaft is
A motor shaft body to which the rotor core is fixed;
A mounting member fixed to one side in the axial direction of the motor shaft main body and to which the external gear is fixed;
Have
The motor shaft body has a hole extending from the end on one side in the axial direction of the motor shaft to the other side in the axial direction,
The mounting member is in the form of a tube which is fitted and fixed in the hole and is open on the other side in the axial direction.
The second oil passage is formed by connecting the inside of the mounting member and the hole in the axial direction, and is connected to the first oil passage through the inside of the mounting member.
The drive device according to any one of claims 1 to 4, wherein the second through hole is provided in the attachment member.
The mounting member is
An insertion portion at least a portion of which is inserted into the shaft insertion hole;
A fixed portion connected to an end portion on one side in the axial direction of the insertion portion, and having an outer diameter larger than the outer diameter of the insertion portion;
Have
The fixed portion is inserted into the pump chamber,
The external gear is fixed to a radially outer surface of the fixing portion,
The drive device according to claim 5, wherein the second through hole is provided at an end portion on one side in the axial direction of the insertion portion.
And a first bearing rotatably supporting the motor shaft on one side in the axial direction with respect to the rotor core,
The motor shaft has an output at an end on the other axial side,
The drive device according to any one of claims 1 to 6, wherein the second through hole is disposed on one side in the axial direction with respect to the first bearing.
The housing is
An inner lid portion which holds a first bearing rotatably supporting the motor shaft and covers one axial side of the stator;
A third oil passage connecting a vertically lower region inside the storage portion and the suction port;
Have
The outer lid is attached to one side of the inner lid in the axial direction,
The drive device according to any one of claims 1 to 7, wherein at least a part of the third oil passage is disposed axially between the inner lid portion and the outer lid portion.
It further comprises a rotation detection unit for detecting the rotation of the rotor,
The rotation detection unit is
An annular detected portion fitted and fixed to the motor shaft;
A sensor unit that detects the rotation of the detected unit;
Have
The housing has an inner lid holding a first bearing rotatably supporting the motor shaft on one side in the axial direction with respect to the rotor core,
The outer lid is attached to one side of the inner lid in the axial direction,
The inner lid portion has a housing recess which is recessed from the surface on one axial direction side of the inner lid portion to the other axial direction side,
The drive device according to any one of claims 1 to 8, wherein the detection target portion, the sensor portion, the first oil passage, and the second through hole are disposed inside the accommodation recess.