WO2018030325A1

WO2018030325A1 - Drive device

Info

Publication number: WO2018030325A1
Application number: PCT/JP2017/028552
Authority: WO
Inventors: 貴之右田; 勇樹石川; 修平中松
Original assignee: 日本電産株式会社
Priority date: 2016-08-09
Filing date: 2017-08-07
Publication date: 2018-02-15

Abstract

In one embodiment of a drive device according to the present invention, a housing includes an outer lid portion covering one side in the axial direction of a motor shaft. A pump unit includes: an externally toothed gear fixed to an end portion at one side in the axial direction of the motor shaft; an internally toothed gear which surrounds the radially outer side of the externally toothed gear and meshes with the externally toothed gear; a pump chamber which is recessed to one side in the axial direction from another side in the axial direction of the outer lid portion, and which houses the internally toothed gear and the externally toothed gear; a suction inlet port capable of sucking oil into the pump chamber; and a discharge port capable of discharging oil from inside the pump chamber. The motor shaft includes a motor shaft main body to which a rotor core is fixed, and a closure member fixed to the motor shaft main body. The closure member overlaps the internally toothed gear as seen in the axial direction, and closes at least a portion of an opening on said other side in the axial direction of the pump chamber.

Description

Drive device

The present invention relates to a drive device.

2. Description of the Related Art A rotating electric machine is known that includes a case for storing a lubricating fluid for lubrication and cooling such as a stator and a rotor. For example, Patent Document 1 describes a rotating electrical machine mounted on a vehicle.

JP 2013-055728 A

The rotating electrical machine as described above may be provided with a pump unit that sucks up 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 connect the shaft of the rotating electrical machine and the pump unit and drive the pump unit using the rotation of the shaft. However, when the shaft and the pump unit are simply connected, it may be time-consuming to assemble the rotating electric machine, for example, it is necessary to fix the external gear to the shaft after the shaft is inserted into the pump chamber. *

In view of the above circumstances, it is an object of the present invention to provide a drive device that drives a pump unit using a motor shaft and has a structure that can reduce the labor of assembly.

One aspect of the drive device according to the present invention includes a rotor having a motor shaft disposed along a central axis extending in one direction and a rotor core fixed to the motor shaft, and is opposed to the rotor via a gap in a radial direction. And a housing having a housing portion that accommodates the rotor and the stator and can store oil, and a pump portion that is driven via the motor shaft, the housing being a shaft of the motor shaft. An outer lid portion covering one side in the direction, and the pump portion surrounds an external gear fixed to an end portion on the one axial side of the motor shaft and a radially outer side of the external gear, and An internal gear that meshes with the tooth gear, a pump chamber that is recessed in the axial direction from the surface on the other axial side of the outer lid portion, and that houses the internal gear and the external gear; The motor shaft has a suction port capable of sucking oil into the pump chamber and a discharge port capable of discharging oil from the pump chamber, and the motor shaft includes a motor shaft body to which the rotor core is fixed, and the motor shaft body. And the closure member overlaps with the internal gear as viewed in the axial direction and closes at least a part of the opening on the other axial side of the pump chamber.

According to one aspect of the present invention, there is provided a drive device that drives a pump unit using a motor shaft and has a structure that can reduce the labor of assembly.

FIG. 1 is a cross-sectional view showing the drive device of the present embodiment. FIG. 2 is a view of the pump unit of this embodiment as viewed from the other side in the axial direction. FIG. 3 is a cross-sectional view showing a part of the driving apparatus of the present embodiment.

The Z-axis direction shown in each figure is a vertical direction Z in which the positive side is the upper side and the negative side is the lower side. In the present embodiment, the vertical direction Z is the vertical direction of each figure. 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”. *

As shown in FIG. 1, the drive device 1 of the present embodiment includes a housing 10, a rotor 20 having a motor shaft 20 a disposed along a central axis J <b> 1 extending in one direction, a rotation detection unit 80, and a stator 30. And a pump unit 40 and

bearings

70 and 71. *

The central axis J1 extends in the left-right direction in FIG. That is, in the present embodiment, the left-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 the center. The circumferential direction is simply called “circumferential direction”. Further, the left side of FIG. 1 in the axial direction is referred to as “one axial side”, and the right side of FIG. 1 in the axial direction is referred to as “the other axial side”. *

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

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

The outer cylinder part 12b is a cylindrical shape extended from the radial direction outer edge part of the annular plate part 12a to the other side of an axial direction. The end portion on the other side in the axial direction of the outer tube portion 12b is fixed in contact with the end portion on the one side in the axial direction of the main body tube portion 11b. The inner cylinder 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 the other axial end of the inner cylinder portion 12c. The bearing holding portion 12e has a cylindrical shape that protrudes from the surface on the other axial side of the inner cylinder bottom portion 12d to the other axial side. The bearing holding part 12e holds the bearing 70 on the inner peripheral surface. That is, the inner lid portion 12 holds the bearing 70. *

The main body part 11 and the inner lid part 12 are fixed to each other, whereby the housing part 14 surrounded by the main body part 11 and the inner lid part 12 is configured. That is, the housing 10 has the accommodating portion 14. The accommodating portion 14 accommodates the rotor 20 and the stator 30 and can store the oil O. The oil O is stored in the lower region in the vertical direction of the storage unit 14. In the present specification, the “lower region in the vertical direction of the housing portion” includes a portion located below the center in the vertical direction Z of the housing portion.

In the present embodiment, the liquid surface OS of the oil O stored in the storage unit 14 is located above the opening 12f. As a result, the opening 12 f is exposed to the oil O stored in the storage portion 14. The liquid surface OS of the oil O fluctuates as the oil O is sucked up by the pump unit 40, but is disposed below the rotor 20 at least when the rotor 20 rotates. Thereby, when the rotor 20 rotates, it can suppress that the oil O becomes rotational resistance of the rotor 20. FIG. *

The outer lid portion 13 is attached to one side in the axial direction of the inner lid portion 12. The outer lid portion 13 includes a lid plate portion 13a and a protruding portion 13b. The lid plate portion 13a has a disk shape that expands in the radial direction. The cover plate part 13a covers one axial side of the motor shaft 20a. That is, the outer lid portion 13 covers one axial side of the motor shaft 20a. The radial outer edge portion of the lid plate portion 13a is fixed to the radial outer edge portion of the annular plate portion 12a. The surface on the other side in the axial direction of the cover plate portion 13a is in contact with the surface on the one side in the axial direction of the annular plate portion 12a. The protruding portion 13b protrudes from the central portion of the lid plate portion 13a to the other side in the axial direction. The protruding portion 13b is inserted and fitted into the inner cylinder portion 12c from one side in the axial direction. The protruding portion 13b is arranged at an interval on one side in the axial direction of the inner cylinder bottom portion 12d. *

A pump chamber 46 is provided in the outer lid portion 13. The pump chamber 46 is recessed from the surface on the other axial side of the outer lid portion 13 to the one axial side. More specifically, the pump chamber 46 is recessed from the surface on the other axial side of the protruding portion 13b to the one axial side. The pump chamber 46 is disposed on the radially inner side of the inner cylindrical portion 12c. The central axis J1 passes through the pump chamber 46. As shown in FIG. 2, the outer shape of the pump chamber 46 is circular when viewed in the axial direction. The pump chamber 46 accommodates an internal gear 43 and an external gear 42 which will be described later. *

As shown in FIG. 1, the housing 10 includes a first oil passage 61 and a third oil passage 63. In the present embodiment, the first oil passage 61 is provided in the outer lid portion 13. The first oil passage 61 is disposed on one axial side of the pump chamber 46. The first oil passage 61 connects the upper end portion of the pump chamber 46 and the central portion of the pump chamber 46 on one axial side of the pump chamber 46. An upper end portion connected to the first oil passage 61 in the pump chamber 46 is a discharge port 45. That is, the first oil passage 61 is connected to the discharge port 45. A central portion connected to the first oil passage 61 in the pump chamber 46 is a connection port 61a. As shown in FIG. 2, the discharge port 45 and the connection port 61a are, for example, circular. The discharge port 45 is disposed above the connection port 61a. The central axis J1 passes through the connection port 61a. *

As shown in FIG. 1, the third oil passage 63 extends upward from the opening 12f. The third oil passage 63 is connected to the lower region in the vertical direction of the accommodating portion 14 through the opening 12f. The upper end portion of the third oil passage 63 is connected to the pump chamber 46 on the other axial side of the pump chamber 46. The portion where the third oil passage 63 is connected in the pump chamber 46 is the suction port 44. That is, the third oil passage 63 connects the lower region in the vertical direction of the housing portion 14 to the suction port 44. As shown in FIG. 2, the suction port 44 has, for example, a circular shape. The suction port 44 is disposed below the discharge port 45 and the connection port 61a. 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 and a second portion 63b. The first portion 63a extends upward from the opening 12f and opens on the inner peripheral surface of the lower end portion of the inner cylinder portion 12c. In the first portion 63a, for example, a groove extending in the vertical direction Z from the surface on one axial side of the annular plate portion 12a and extending in the vertical direction Z is closed by the surface on the other axial side of the lid plate portion 13a. Composed. Accordingly, the first portion 63a is disposed between the inner lid portion 12 and the outer lid portion 13 in the axial direction. *

The second portion 63b is connected to the upper end portion of the first portion 63a. The second portion 63b is disposed on the radially inner side of the inner cylinder portion 12c. The second portion 63 b is connected to the suction port 44. The second portion 63b is configured, for example, by closing the opening on the one axial side of the inner cylinder portion 12c with the outer lid portion 13. Accordingly, the second portion 63b is disposed between the inner lid portion 12 and the outer lid portion 13 in the axial direction. Thus, according to the present embodiment, at least a part of the third oil passage 63 is disposed between the inner lid portion 12 and the outer lid portion 13 in the axial direction. Therefore, at least a part of the third oil passage 63 can be configured by the inner lid portion 12 and the outer lid portion 13 fixed to each other, and the third oil passage 63 can be easily manufactured. In the present embodiment, since the entire third oil passage 63 is disposed between the inner lid portion 12 and the outer lid portion 13 in the axial direction, the third oil passage 63 can be more easily manufactured. *

The rotor 20 includes a motor shaft 20 a, a rotor core 22, a magnet 23, a first end plate 24, and a second end plate 25. The motor shaft 20 a includes a motor shaft main body 21 and a closing member 50. The motor shaft 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 medium diameter portion 21b, a second medium diameter portion 21c, a small diameter portion 21d, and an output portion 21e. *

The large diameter portion 21a 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 axial side of the large diameter portion 21a. A nut 90 is fastened to the male screw portion of the large diameter portion 21a. The first medium diameter portion 21b is connected to the large diameter portion 21a on one axial side of the large diameter portion 21a. The outer diameter of the first medium diameter portion 21b is smaller than the outer diameter of the large diameter portion 21a. The end portion on the other axial side of the first medium diameter portion 21b is rotatably supported by the bearing 70. *

The second medium diameter portion 21c is connected to the large diameter portion 21a on the other axial side of the large diameter portion 21a. The outer diameter of the second medium diameter portion 21c is smaller than the outer diameter of the large diameter portion 21a. The end portion on the one axial side of the second medium diameter portion 21c is rotatably supported by the bearing 71. The

bearings

70 and 71 rotatably support the motor shaft 20a. The

bearings

70 and 71 are ball bearings, for example. *

The small diameter portion 21d is connected to the first medium diameter portion 21b on one axial side of the first medium diameter portion 21b. An end portion on one side in the axial direction of the small diameter portion 21 d is an end portion on one side in the axial direction of the motor shaft main body 21. The end portion on one side in the axial direction of the small diameter portion 21d is disposed on the radially inner side of the inner cylinder portion 12c. The outer diameter of the small diameter portion 21d is smaller than the outer diameter of the first medium diameter portion 21b. That is, the small diameter portion 21d is a portion whose outer diameter decreases toward one side in the axial direction. *

The output part 21e is connected to the second medium diameter part 21c on the other axial side of the second medium diameter part 21c. The output portion 21e is an end portion on the other side in the axial direction of the motor shaft main body 21. The outer diameter of the output part 21e is smaller than the outer diameter of the small diameter part 21d. The output portion 21e protrudes outside the housing 10 through the bottom portion 11a in the axial direction. *

The motor shaft main body 21 has a flange portion 21f. The flange portion 21f protrudes radially outward from the outer peripheral surface of the large diameter portion 21a. The flange portion 21f has an annular plate shape that is provided over the circumference of the outer peripheral surface of the large diameter portion 21a. The flange portion 21f is provided at the end portion on the other axial side of the large diameter portion 21a. *

The closing member 50 is fixed to the motor shaft main body 21 on one side in the axial direction of the motor shaft main body 21. The closing member 50 has a cylindrical shape that is fitted to the motor shaft main body 21. More specifically, the closing member 50 has a cylindrical shape centered on the central axis J1, and is fitted and fixed to the small diameter portion 21d from one side in the axial direction. The closing member 50 opens on both sides in the axial direction. The closing member 50 is disposed on the radially inner side of the inner cylinder portion 12c. *

The closing member 50 includes a closing main body portion 51 and a fixing portion 52. The closing main body 51 has a cylindrical shape that is fitted and fixed to the small diameter portion 21d. The closing main body 51 includes a closing lid part 51a and a fitting part 51b. The closing lid portion 51a has an annular plate shape centering on the central axis J1 and extending in the radial direction. The closing lid 51 a closes a part of the opening on the other axial side of the pump chamber 46. That is, the closing member 50 closes at least a part of the opening on the other axial side of the pump chamber 46. In the present embodiment, the outer diameter of the closing lid portion 51 a is smaller than the inner diameter of the pump chamber 46. Therefore, the closing lid portion 51 a closes a part on the radially inner side of the opening on the other axial side of the pump chamber 46. *

The radially outer edge portion of the closing lid portion 51a overlaps with the internal gear 43 when viewed in the axial direction. That is, the closing member 50 overlaps with the internal gear 43 when viewed in the axial direction. The closing lid 51a supports the internal gear 43 from the other side in the axial direction. The end surface on one side in the axial direction of the small diameter portion 21d is in contact with the surface on the other side in the axial direction of the closing lid portion 51a. The fitting portion 51b has a cylindrical shape extending from the radially outer edge portion of the closing lid portion 51a to the other side in the axial direction. The fitting portion 51b is fitted into the small diameter portion 21d from the outside in the radial direction. *

The fixing portion 52 has a cylindrical shape extending from the closing main body portion 51 to one side in the axial direction. More specifically, the fixing portion 52 has a cylindrical shape that extends from the radially inner edge of the closing lid portion 51a toward the one axial side with the central axis J1 as the center. The fixing portion 52 has an outer diameter smaller than that of the closing main body portion 51. The fixing portion 52 is inserted into the pump chamber 46. The end surface on one side in the axial direction of the fixed portion 52 is in contact with the surface on one side in the axial direction of the pump chamber 46. The opening on the one side in the axial direction of the fixed portion 52 is connected to the connection port 61a so as to face in the axial direction. *

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 that extends from the end on one side in the axial direction of the motor shaft 20a to the other side in the axial direction. The second oil passage 62 opens on one side in the axial direction. The second oil passage 62 extends from the end on one side in the axial direction of the closing member 50 to the end on the other side in the axial direction of the second medium diameter portion 21c, and is provided across the closing member 50 and the motor shaft main body 21. It is done. The second oil passage 62 is configured by connecting the inside of the fixed portion 52 and a hole portion recessed in the other axial direction from the end on one axial direction of the motor shaft body 21 in the axial direction. That is, the radially inner side surface of the closing 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 has a circular shape centering on the central axis J1 in a cross section orthogonal to the axial direction. The inner diameter of the portion provided in the closing 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 fixed portion 52 is smaller than the inner diameter of the hole portion that constitutes the second oil passage 62 provided in the motor shaft main body 21. The second oil passage 62 is connected to the first oil passage 61 by connecting the opening on the one axial side of the fixed portion 52 to the connection port 61 a. That is, the second oil passage 62 opens into the first oil passage 61 at the end portion on the one axial side of the motor shaft 20a. *

The motor shaft 20a has first through holes 26a to 26d that connect the second oil passage 62 and the outer peripheral surface of the motor shaft 20a. The first through holes 26a to 26d extend in the radial direction. The first through

holes

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

holes

26a and 26b are disposed between the nut 90 and the flange portion 21f in the axial direction. As shown in FIG. 3, the radially outer end of the first through hole 26 a opens in the axial gap 27 a between the first end plate 24 and the rotor core 22. The radially outer end of the first through hole 26 b opens in the axial gap 27 b between the second end plate 25 and the rotor core 22. *

The first through hole 26c is provided in the first medium diameter portion 21b. The radially outer end of the first through hole 26c opens on the radially inner side of the bearing holding portion 12e on one axial side of the bearing 70. The first through hole 26d is provided in the second medium diameter portion 21c. The radially outer end of the first through hole 26d opens on the radially inner side of the bearing holding portion 11c on the other axial side of the bearing 71. For example, a plurality of first through holes 26a to 26d are provided along the circumferential direction. *

As shown in FIG. 1, the rotor core 22 has an annular shape fixed to the motor shaft main body 21. In the present embodiment, the rotor core 22 is fitted into the large diameter portion 21a. The rotor core 22 has a magnet insertion hole 22b that penetrates the rotor core 22 in the axial direction. A plurality of magnet insertion holes 22b 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 have an annular plate shape that expands in the radial direction. A 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 while being in contact with the rotor core 22. *

As shown in FIG. 3, the first end plate 24 is disposed on one axial side 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 contacts the radially outer edge portion of the surface on the one axial side of the rotor core 22. The radially outer edge of the first end plate 24 overlaps with the opening on one axial side of the magnet insertion hole 22b in the axial direction, and presses the magnet 23 inserted into the magnet insertion hole 22b from one axial side. A portion radially inward from the radially outer edge portion of the first end plate 24 faces the surface on one side in the axial direction of the rotor core 22 in the axial direction through a gap 27a. *

The first end plate 24 has an ejection groove 24 a that is recessed from the surface on one side in the axial direction of the first end plate 24 toward the other side in the axial direction. The ejection groove 24a extends 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 24a opens to the radially outer side of the first end plate 24, and opposes a coil 32, which will be described later, with a gap in the radial direction. The opening on the one axial side in the radially inner portion of the ejection groove 24 a is closed by a washer 91 that is sandwiched and fixed between the nut 90 and the first end plate 24 in the axial direction. The washer 91 has an annular plate shape that expands in the radial direction. *

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

The radially inner portion of the second end plate 25 is radially opposed to the surface on the other axial side of the rotor core 22 via the gap 27b. The second end plate 25 has an ejection groove 25 a that is recessed from the surface on the other axial side of the second end plate 25 to the one axial side. 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 to the radially outer side of the second end plate 25, and opposes the coil 32, which will be described later, with a gap in the radial direction. The opening on the other side in the axial direction in 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 sandwiched in the axial direction by the nut 90, the washer 91, and the flange portion 21f. When the nut 90 is tightened into 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. Thereby, the 1st end plate 24, the rotor core 22, and the 2nd end plate 25 are fixed to the motor shaft 20a. *

The rotation detector 80 shown 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) type resolver. The rotation detector 80 is disposed on the radially inner side of the inner cylinder portion 12c. The rotation detection unit 80 includes a detected unit 81 and a sensor unit 82. *

The detected part 81 has an annular shape extending in the circumferential direction. The detected part 81 is fitted and fixed to the motor shaft 20a. More specifically, the detected portion 81 is fitted and fixed to the small diameter portion 21d. The surface on the other axial side of the radially inner edge of the detected portion 81 is in contact with the step between the first medium diameter portion 21b and the small diameter portion 21d. The surface on the one axial side of the radially inner edge of the detected portion 81 is in contact with the end surface on the other axial side of the fitting portion 51b. That is, the detected portion 81 is sandwiched in the axial direction in a state where it is in contact with the blocking member 50 and the step on the other axial side of the small diameter portion 21d. Therefore, the detected portion 81 is positioned in the axial direction and held by the motor shaft 20a, and is prevented from coming off from the motor shaft main body 21 to the one side in the axial direction. The detected part 81 is made of a magnetic material. *

The sensor portion 82 is disposed between the inner lid portion 12 and the outer lid portion 13 in the axial direction. More specifically, the sensor part 82 is fixed to the surface on the one axial side of the inner cylinder bottom part 12d on the radially inner side of the inner cylinder part 12c. That is, the sensor unit 82 is attached to the inner lid unit 12. Therefore, it is easy to attach the sensor unit 82. The sensor unit 82 has an annular shape that surrounds the radially outer side of the detected portion 81. The sensor unit 82 has a plurality of coils along the circumferential direction. When the detected portion 81 rotates together with the motor shaft 20a, an induced voltage corresponding to the circumferential position of the detected portion 81 is generated in the coil of the sensor portion 82. The sensor unit 82 detects the rotation of the detected unit 81 by detecting the induced voltage. Thereby, the rotation detector 80 detects the rotation of the rotor 20 by detecting the rotation of the motor shaft 20a. *

The stator 30 faces the rotor 20 via a gap in the radial direction. The stator 30 includes a stator core 31 and a plurality of coils 32 attached to 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 cylinder portion 11b. The stator core 31 is opposed to the outer side in the radial direction of the rotor core 22 via a gap. *

The pump unit 40 is provided at the center of the outer lid unit 13. The pump part 40 is arrange | positioned at the axial direction one side of the motor shaft 20a. The pump unit 40 includes an external gear 42, an internal gear 43, the above-described pump chamber 46, a suction port 44, a discharge port 45, and a storage unit 48. The external gear 42 is a gear that can rotate around the central axis J1. The external gear 42 is fixed to an end portion on one axial side of the motor shaft 20a. 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 closing member 50. Thereby, 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 by adjusting the dimensions of the closing member 50. *

The surface on the other axial side of the external gear 42 is in contact with the surface on the one axial side of the closing lid portion 51a. The external gear 42 is accommodated in the pump chamber 46. As shown in FIG. 2, the external gear 42 has a plurality of tooth portions 42a 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 is rotatable 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 tooth portions 43a on the inner peripheral surface. The tooth profile of the tooth portion 43a of the internal gear 43 is a trochoidal tooth profile. Thus, since the tooth profile of the tooth portion 42a of the external gear 42 and the tooth profile of the tooth portion 43a of the internal gear 43 are trochoidal tooth profiles, a trochoid pump can be configured. Therefore, noise generated from the pump unit 40 can be reduced, and the pressure and amount of the oil O discharged from the pump unit 40 can be easily stabilized. *

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 a gap between the external gear 42 and the internal gear 43. The suction port 44 allows the oil O stored in the storage portion 14 to pass through the opening 12f and the third oil passage 63 in the pump chamber 46, more specifically, between the external gear 42 and the internal gear 43. Inhalable. As shown in FIG. 2, the suction port 44 is disposed above the lower end of the storage portion 48 and 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 axial side of the pump chamber 46. The discharge port 45 is connected to a 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. *

The reservoir 48 is connected to the pump chamber 46 on one axial side of the lower region in the vertical direction of the pump chamber 46. As shown in FIG. 2, the shape of the storage portion 48 is an arc shape that protrudes downward when viewed in the axial direction. Part of the oil O sucked into the pump chamber 46 from the suction port 44 flows into the storage portion 48. *

Since the suction port 44 is disposed above the lower end of the storage unit 48, even when the pump unit 40 is stopped, at least a part of the oil O that has flowed into the storage unit 48 flows from the suction port 44. It is stored in the storage unit 48 without returning to the storage unit 14. Thereby, when the pump part 40 is stopped, the lower part of the external gear 42 in the pump chamber 46 and the lower part of the internal gear 43 are in contact with the oil O in the storage part 48. Can be. Therefore, when the pump portion 40 is driven again, the space between the tooth portion 42 a of the external gear 42 and the tooth portion 43 a of the internal gear 43, the inner peripheral surface of the pump chamber 46, and the outer peripheral surface of the internal gear 43 Oil O can be interposed between the two, and seizure can be suppressed. *

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 that meshes 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. In this way, 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 flows into the second oil passage 62 from the connection port 61a. As indicated by an arrow in FIG. 3, the oil O that has flowed into the second oil passage 62 receives a force radially outward due to the centrifugal force of the rotating motor shaft 20a, passes through the first through holes 26a to 26d, and the motor. It flows out of the shaft 20a. *

In the present embodiment, since the first through 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 through hole 26a flows into the gap 27a. And the oil O which flowed into the clearance gap 27a is ejected toward the radial direction outer side from the ejection groove 24a. In the present embodiment, the opening on the one axial side in the radially inner portion of the ejection groove 24 a is closed by the washer 91, so that the oil O that has flowed into the ejection groove 24 a is guided radially outward by the washer 91. It's easy to do. *

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

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 be cooled by the oil O until it is ejected from the

ejection grooves

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

Since the first through hole 26c opens to the inside of the bearing holding portion 12e in the radial direction, the oil O flowing out of the first through hole 26c is supplied to the bearing 70. Since the first through hole 26d opens to the inside of the bearing holding portion 11c in the radial direction, the oil O flowing out of the first through hole 26d is supplied to the bearing 71. Thereby, the oil O can be used as a lubricant for the

bearings

70 and 71.

Although FIG. 3 shows an example in which the oil O is ejected upward from the

ejection grooves

24a and 25a, the present invention is not limited to this. Since the rotor 20 rotates, the circumferential positions of the

ejection grooves

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

ejection grooves

24a and 25a changes in the circumferential direction, and the plurality of coils 32 arranged 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 oil O stored in the housing 10 is sucked up by the pump unit 40 and supplied to the rotor 20, the stator 30, and the

bearings

70 and 71. be able to. Thus, the oil O stored in the housing 10 can be used to cool the rotor 20 and the stator 30, and the lubricity between the

bearings

70 and 71 and the motor shaft body 21 can be improved. The oil O supplied to the stator 30 and the

bearings

70 and 71 falls in the housing portion 14 and is stored again in the lower region of the housing portion 14. Thereby, the oil O in the accommodating part 14 can be circulated. *

For example, conventionally, when the external gear is inserted into the pump chamber with the external gear fixed to the motor shaft, it has been difficult to close the opening of the pump chamber on the side where the motor shaft is inserted. Therefore, for example, after inserting the motor shaft into the pump chamber from the hole provided on the closed side of the pump chamber, it is necessary to insert an external gear into the pump chamber from the opening side of the pump chamber and fix it to the motor shaft. was there. Therefore, it takes time to assemble the drive device, and the structure of the drive device tends to be complicated. *

On the other hand, according to this embodiment, at least a part of the opening on the other axial side of the pump chamber 46 is closed by the closing member 50 of the motor shaft 20a. Therefore, with the external gear 42 fixed to the motor shaft 20a, the end of the motor shaft 20a on one side in the axial direction is inserted into the pump chamber 46 together with the external gear 42, so that the external gear 42 is connected to the pump chamber. At the same time, the opening on the other axial side of the pump chamber 46 can be closed by the closing member 50. Therefore, it is possible to reduce the time and effort for assembling the drive device 1 and to easily prevent the structure of the drive device 1 from becoming complicated. *

In addition, since the closing member 50 that closes the pump chamber 46 rotates together with the external gear 42, the closing member 50 is oil against the oil O that flows between the external gear 42 and the internal gear 43. It moves in the same circumferential direction as that of O. As a result, the oil O in the pump chamber 46 can be easily sent from the suction port 44 to the discharge port 45. *

Further, according to the present embodiment, by providing the first oil passage 61 and the second oil passage 62, the oil O discharged from the discharge port 45 can be sent into the motor shaft 20a. Further, since the first through holes 26 a to 26 d are provided, the oil O that has flowed into the second oil passage 62 can be supplied to the stator 30 and the

bearings

70 and 71. *

Further, according to the present embodiment, the second oil passage 62 provided in the motor shaft 20a opens to the first oil passage 61 connected to the discharge port 45 at the end portion on one axial side of the motor shaft 20a. . Since the external gear 42 is fixed to the end portion on the one axial side of the motor shaft 20a, the end portion on the one axial side of the motor shaft 20a is disposed at a position relatively close to the discharge port 45. Therefore, the length of the first oil passage 61 connecting the discharge port 45 and the second oil passage 62 can be shortened. Therefore, according to the present embodiment, the total length of the oil passage from the opening 12f to the second oil passage 62 can be easily shortened. Thereby, the structure of the drive device 1 can be easily simplified, and the drive device 1 can be easily manufactured. *

Further, according to the present embodiment, the radially inner side surface of the closing member 50 constitutes a part of the radially inner side surface of the second oil passage 62. Therefore, the oil O can be allowed to flow into the second oil passage 62 from the closing member 50 while fixing the external gear 42 to the closing member 50. Accordingly, as described above, the motor shaft main body 21 and the external gear 42 can be fixed via the closing member 50 without changing the dimensions of the motor shaft main body 21 and the external gear 42, and the second oil It is easy to open the path 62 to the first oil path 61.

The present invention is not limited to the above-described embodiment, and other configurations can be employed. The closing member 50 may close the entire opening on the other axial side of the pump chamber 46. In this case, the outer diameter of the closing lid 51 a is equal to or larger than the inner diameter of the pump chamber 46. Further, if a part of the opening on the other axial side of the pump chamber 46 is blocked by the closing member 50, the other part of the opening on the other axial side of the pump chamber 46 is blocked by a member other than the closing member 50. May be. Further, the external gear 42 may be directly fixed to the motor shaft main body 21 without using the closing member 50. In this case, the second oil passage 62 may be provided only inside the motor shaft main body 21, for example.

The rotor core 22 may be fixed to the outer peripheral surface of the motor shaft 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. In this case, the oil O flowing out of the first through

holes

26a and 26b may be directly supplied to the coil 32, or a hole connected to the first through hole 26a is provided in the rotor core 22, and the hole of the rotor core 22 is provided. Oil O may be supplied to the coil 32 via Further, the oil O may be supplied to the stator core 31. *

Further, the location where the oil O discharged from the discharge port 45 is supplied is not particularly limited, and may be supplied to only one or two of the rotor 20, the stator 30, and the

bearings

70 and 71, for example. However, it may not be supplied to either. The oil O discharged from the discharge port 45 may be supplied to, for example, the inner side surface of the upper area in the vertical direction of the storage unit 14. In this case, the stator 30 can be indirectly cooled by cooling the housing 10. Further, any one or more of the first through holes 26a to 26d may not be provided. The tooth profile of the tooth portion 42a of the external gear 42 and the tooth profile of the tooth portion 43a of the internal gear 43 may be a cycloid tooth profile or an involute tooth profile. *

In addition, the use of the drive apparatus of embodiment mentioned above is not specifically limited. Moreover, each structure mentioned above can be suitably combined in the range which is not mutually contradictory.

DESCRIPTION OF SYMBOLS 1 ... Drive device, 10 ... Housing, 11 ... Main-body part, 12 ... Inner cover part, 13 ... Outer cover part, 14 ... Storage part, 20 ... Rotor, 20a ... Motor shaft, 21 ... Motor shaft main body, 21d ... Small diameter part , 22 ... rotor core, 26a, 26b, 26c, 26d ... first through hole, 30 ... stator, 40 ... pump section, 42 ... external gear, 43 ... internal gear, 44 ... suction port, 45 ... discharge port, 46 DESCRIPTION OF SYMBOLS ... Pump chamber, 48 ... Storage part, 50 ... Blocking member, 51 ... Blocking main-body part, 52 ... Fixing part, 61 ... 1st oil path, 62 ... 2nd oil path, 63 ... 3rd oil path, 70, 71 ... Bearing, 80 ... Rotation detection part, 81 ... Detected part, 82 ... Sensor part, J1 ... Center axis, O ... Oil, Z ... Vertical direction

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 facing the rotor via a gap in the radial direction;

A housing having an accommodating portion capable of accommodating the rotor and the stator and storing oil;

A pump unit driven via the motor shaft;

With

The housing has an outer lid that covers one side in the axial direction of the motor shaft,

The pump part is

An external gear fixed to an end portion on one axial side 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 that is recessed from the surface on the other side in the axial direction of the outer lid portion to one side in the axial direction, and houses 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 motor shaft is

A motor shaft body to which the rotor core is fixed;

A closing member fixed to the motor shaft body;

Have

The closing member overlaps with the internal gear as viewed in the axial direction, and closes at least a part of the opening on the other axial side of the pump chamber.
The closing member is

A cylindrical closing main body for closing the pump chamber;

A cylindrical portion extending from the closed body portion to one side in the axial direction and having a smaller outer diameter than the closed body portion,

Have

The drive device according to claim 1, wherein the external gear is fixed to an outer peripheral surface of the fixing portion.
A rotation detection unit that detects rotation of the rotor;

The rotation detector

An annular detected portion fitted and fixed to the motor shaft;

A sensor unit for detecting rotation of the detected unit;

Have

The motor shaft main body has a small diameter portion whose outer diameter decreases toward one side in the axial direction,

The closing member is a cylindrical shape that is fitted and fixed to the small diameter portion,

3. The drive according to claim 1, wherein the detected portion is fitted in the small diameter portion, and is sandwiched in the axial direction in a state of being in contact with the blocking member and a step on the other axial side of the small diameter portion. apparatus.
The housing has a first oil passage connected to the discharge port,

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;

Have

The first oil passage is disposed on one axial side of the pump chamber,

The drive device according to any one of claims 1 to 3, wherein the second oil passage opens to the first oil passage at an end portion on one axial side of the motor shaft.
The closing member has a cylindrical shape that opens on both sides in the axial direction and is fitted to the motor shaft body,

5. The drive device according to claim 4, wherein a radially inner side surface of the closing member constitutes a part of a radially inner side surface of the second oil passage.
The housing is

An inner lid that holds a bearing that rotatably supports the motor shaft and covers one side in the axial direction of the stator;

A third oil passage connecting the lower area in the vertical direction of the housing part and the suction port;

Have

The outer lid is attached to one side in the axial direction of the inner lid,

6. The driving device according to claim 1, wherein at least a part of the third oil passage is disposed between the inner lid portion and the outer lid portion in an axial direction.
A rotation detection unit that detects rotation of the rotor;

The rotation detection unit includes an annular detection unit that is fitted and fixed to the motor shaft;

A sensor unit for detecting rotation of the detected unit;

Have

The drive unit according to claim 6, wherein the sensor unit is attached to the inner lid unit.
The pump unit has a storage unit connected to the pump chamber on one axial side of the lower region in the vertical direction of the pump chamber,

The suction port is disposed vertically above a vertical lower end of the storage unit and vertically upward of a vertical lower end of the external gear. The drive device according to claim 7.