CN214036097U

CN214036097U - Electric oil pump

Info

Publication number: CN214036097U
Application number: CN201990000648.5U
Authority: CN
Inventors: 片冈慈裕; 小林喜幸
Original assignee: Nidec Tosok Corp
Current assignee: Nidec Tosok Corp
Priority date: 2018-04-24
Filing date: 2019-03-27
Publication date: 2021-08-24
Anticipated expiration: 2029-03-27
Also published as: JP7310804B2; JPWO2019208078A1; WO2019208078A1

Abstract

The utility model provides an electric oil pump. The electric oil pump (1) is provided with a motor unit (10), a pump unit (40), and an inverter unit (70) fixed to the motor unit (10). The motor unit (10) has a rotor, a stator, and a motor case (13) that houses the rotor and the stator. The pump section (40) has: a pump rotor; and a pump housing (51) provided with a suction port (63) for sucking oil and a discharge port (64) for discharging oil, wherein the pump housing (51) houses the pump rotor. The pump housing (51) has a pump body (52) that houses the pump rotor, and a pump cover (57) that is attached to the pump body (52). The pump cover (57) has an end surface (58) provided on one axial side and a cylindrical side surface (61) that extends to the other axial side and is connected to the peripheral edge portion of the end surface (58). A suction port (63) is provided on one of the end surface (58) and the side surface (61), and a discharge port (64) is provided on the other.

Description

Electric oil pump

Technical Field

The utility model relates to an electric oil pump.

Background

For example, patent document 1 discloses an electric oil pump in which a motor unit, a pump unit, and an inverter unit having a circuit board are integrated. The pump section includes a pump body that houses a pump rotor, and a pump cover that is attached to one axial side of the pump body.

The pump cover has a suction port for sucking oil and a discharge port for discharging oil. The suction port and the discharge port are provided on an end surface of the pump cover on one axial side. The suction port is open at one axial end of the suction port protruding from the end surface. The discharge port is open at an end portion on one axial side of the discharge port protruding from the end surface. The suction port and the discharge port are arranged adjacent to the end surface in the radial direction. The axial projection length of the discharge port is longer than the axial projection length of the suction port. Therefore, the oil passage can be easily brought into contact with the suction port and the discharge port, respectively.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-172350

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

However, in the electric oil pump described in patent document 1, the axial projection length of the discharge port is longer than the axial projection length of the suction port, which leads to an increase in the axial size of the electric oil pump.

An object of the present invention is to provide an electric oil pump capable of suppressing an increase in the size of the electric oil pump in the axial direction.

Means for solving the problems

The utility model 1 that this application exemplifies is an electric oil pump, its characterized in that, this electric oil pump has: a motor unit having a shaft centered on a central axis extending in an axial direction; a pump section that is located on one axial side of the motor section and that discharges oil by being driven by the motor section via the shaft; and an inverter unit that is located on the other axial side of the motor unit and is fixed to the motor unit, the motor unit including: a rotor fixed to the other axial side of the shaft; a stator located radially outward of the rotor; and a motor case that houses the rotor and the stator, the pump section including: a pump rotor attached to the shaft protruding from the motor unit to one axial side; and a pump housing that is provided with a suction port that sucks in the oil and a discharge port that discharges the oil, and that houses the pump rotor, the pump housing including: a pump body having a housing portion that houses the pump rotor; and a pump cover mounted on one axial side of the pump body, the pump cover having: an end surface provided on one side in the axial direction; and a cylindrical side surface which is connected to a peripheral edge portion of the end surface and extends to the other side in the axial direction, wherein the suction port is provided at one of the end surface and the side surface, and the discharge port is provided at the other of the end surface and the side surface.

Preferably, the end surface has a circular shape when viewed in the axial direction, the suction port is provided in the end surface, the discharge port is provided in the side surface, the suction port is disposed in a peripheral portion on one side in the radial direction of the end surface, and the discharge port is disposed at a position facing the suction port with respect to the center axis.

Preferably, the suction port has a circular shape when viewed in the axial direction, and the discharge port has an elongated hole shape extending in the circumferential direction of the side surface.

Preferably, the opening area of the discharge port is the same as or slightly smaller than the opening area of the suction port.

Preferably, the discharge port is disposed at a position having a predetermined distance from one axial end of the side surface to the other axial end, and a seal member is annularly provided between the one axial end of the side surface and the discharge port, the seal member causing a supply oil passage for supplying the oil to the suction port to be in close contact with the side surface.

Effect of the utility model

According to the invention of claim 1, it is possible to provide the electric oil pump capable of suppressing the increase in the size of the electric oil pump in the axial direction.

Drawings

Fig. 1 is a perspective view of an electric oil pump of embodiment 1.

Fig. 2 is a sectional view showing an internal configuration of the electric oil pump.

Fig. 3 is an enlarged sectional view of the fixing member.

Fig. 4 is an enlarged side view of the fixing member.

Fig. 5 is a bottom view of the electric oil pump.

Detailed Description

Hereinafter, an electric oil pump according to an embodiment of the present invention will be described with reference to the drawings. In the drawings below, in order to facilitate understanding of each structure, the actual structure may be different from the scale, the number, and the like of each structure.

In the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the Z-axis direction is a direction parallel to the axial direction of the central axis J shown in fig. 2. The X-axis direction is a direction parallel to the short side direction of the electric oil pump 1 shown in fig. 1, that is, a direction perpendicular to the paper surface of fig. 1. The Y-axis direction is a direction perpendicular to both the X-axis direction and the Z-axis direction. In any of the X-axis direction, the Y-axis direction, and the Z-axis direction, one side of the arrow shown in the figure is set as the + side, and the opposite side is set as the-side.

In the following description, the positive side (+ Z side) in the Z-axis direction is referred to as "rear side", and the negative side (-Z side) in the Z-axis direction is referred to as "front side". The rear side and the front side are only names for explanation, and the actual positional relationship and direction are not limited. Unless otherwise specified, a direction parallel to the central axis J (Z-axis direction) is simply referred to as "axial direction", a radial direction about the central axis J is simply referred to as "radial direction", and a circumferential direction about the central axis J, that is, a direction (θ direction) around the central axis J is simply referred to as "circumferential direction".

In the present specification, the term "extend in the axial direction" includes a case where the extension is strictly in the axial direction (Z-axis direction), and a case where the extension is in a direction inclined by less than 45 ° with respect to the axial direction. In the present specification, the term "extend in the radial direction" includes a case where the extension is strictly in the radial direction, that is, in the direction perpendicular to the axial direction (Z-axis direction), and a case where the extension is in a direction inclined by less than 45 ° with respect to the radial direction.

[ 1 st embodiment ]

< integral Structure >

Fig. 1 is a perspective view of an electric oil pump of embodiment 1. Fig. 2 is a sectional view showing an internal configuration of the electric oil pump. As shown in fig. 1 and 2, the electric oil pump 1 of the present embodiment includes a motor section 10, a pump section 40, and an inverter section 70. The motor section 10 and the pump section 40 are arranged in the axial direction. The motor unit 10 has a shaft 11 disposed along a central axis J extending in the axial direction. The pump section 40 is located on one axial side (front side) of the motor section 10, and is driven by the motor section 10 via the shaft 11 to discharge oil. The inverter unit 70 is located on the other axial side (rear side) of the motor unit 10 and is fixed to the motor unit 10. Hereinafter, each component will be described in detail.

< inverter part 70 >

The inverter unit 70 includes an inverter case 73, and the inverter case 73 includes a circuit board housing portion 73a housing a circuit board 75. The inverter case 73 has a bottomed cylindrical shape having a bottom portion 73b on the motor portion 10 side. The inverter case 73 extends radially outward from the other side (rear side) in the axial direction of the motor case 13. In the present embodiment, the inverter case 73 is made of a resin material, and the inverter case 73 has a rectangular shape as viewed in the axial direction. The inverter section 70 further includes a cover section 90, and the cover section 90 covers an opening section 73c that opens to the other side (rear side) in the axial direction of the inverter housing 73.

As shown in fig. 1, a side surface 73d of the inverter case 73 in a direction perpendicular to a direction extending outward in the radial direction when viewed in the axial direction has a concave portion 73e recessed inward of the inverter case 73. In the present embodiment, the concave portions 73e are provided at both ends of the inverter case 73 in the X axis direction, and are provided at positions radially outside the cylindrical portion 14 and near the flange portion 77 located on the negative side (the (-Y side) in the Y axis direction of the cylindrical portion 14. That is, the concave portions 73e are provided at two positions on the side surfaces 73d of the inverter case 73 on both sides in the X axis direction, and are provided at four positions in total. The recess 73e provided on one side of the inverter case 73 in the X-axis direction and the recess 73e provided on the other side of the inverter case 73 in the X-axis direction are disposed so as to face a virtual line a (see fig. 5) intersecting the center axis J and extending in the Y-axis direction. The flange portion 77 will be described later.

A plurality of flange portions 77 extending radially with respect to the center axis J are provided on the side surfaces of the inverter case 73 on both sides in the X-axis direction. In the present embodiment, four flange portions 77 are provided with a space in the circumferential direction. The flange portion 77 is provided with a fixing hole portion 77a through which a bolt passes. The fixing hole 77a is a hole through which a bolt for fixing the electric oil pump 1 to a fixing object (not shown) passes.

Fig. 3 is an enlarged sectional view of the fixing member. Fig. 4 is an enlarged side view of the fixing member. As shown in fig. 3 and 4, the recess 73e has a surface 73e1, and the surface 73e1 is recessed from the side surface 73d of the inverter case 73 at a position spaced apart from the end surface 73f toward the other axial side (rear side). The end surface 73f is a surface of the inverter case 73 facing the motor unit 10.

The recess 73e has a pair of side surface portions 73e2, and the pair of side surface portions 73e2 extend from the surface portion 73e1 to the other side (rear side) in the axial direction on the side surface 73d and extend in the axial direction on both sides in the direction in which the inverter case 73 extends. The distance L between the pair of side surface portions 73e2 is greater than the width W of the clinch portion 31. The caulking portion 31 will be described later.

< motor part 10 >

As shown in fig. 2, the motor unit 10 includes a motor case 13, a rotor 20, a shaft 11, and a stator 22.

The motor unit 10 is, for example, an inner rotor type motor, the rotor 20 is fixed to the other side (rear side) in the axial direction of the shaft 11, and the stator 22 is positioned radially outward of the rotor 20.

(Motor case 13)

The motor case 13 houses the rotor 20 and the stator 22. Further, the motor case 13 has a cylindrical portion 14 and a base plate 25. The cylindrical portion 14 is located radially outward of the stator 22 and surrounds the stator 22. The base plate 25 is connected to an end portion of the cylindrical portion 14 on the inverter portion 70 side, and the base plate 25 is disposed on one side (front side) in the axial direction of the inverter case 73 and expands in the radial direction with respect to the center axis J.

(barrel portion 14)

The cylindrical portion 14 extends in the axial direction and has a through hole 14a therein. The shaft 11, the rotor 20, and the stator 22 of the motor unit 10 are disposed in the through hole 14 a. The outer surface of the stator 22, that is, the outer surface of a core back 22a described later is fitted to the inner surface 14b of the tube 14. Thereby, the stator 22 is housed in the cylindrical portion 14. The barrel portion 14 is made of a metal material.

(substrate 25)

The substrate 25 is connected to the end of the cylindrical portion 14 on the inverter portion 70 side. As shown in fig. 1 and 2, the substrate 25 has a plate shape, and extends in a direction along an end surface 73f on one axial side of the inverter case 73 so as to cover the end surface 73 f. In the present embodiment, the substrate 25 protrudes radially outward from the tube portion 14, and has a rectangular shape in the Y-axis direction when viewed in the axial direction. The substrate 25 protrudes from the cylinder 14 to the negative side (-Y side) in the Y axis direction more than to the positive side. The tube portion 14 of the motor case 13 and the base plate 25 are an integrated body formed by drawing.

Fig. 5 is a bottom view of the electric oil pump. As shown in fig. 1 and 5, a plurality of flange portions 25a projecting radially are provided on the base plate 25 radially outward of the cylindrical portion 14. In the present embodiment, four flange portions 25a are provided at intervals in the circumferential direction. The flange portion 25a is provided with a fixing hole portion 25b through which a bolt passes. The fixing hole 25b is a hole through which a bolt for fixing the electric oil pump 1 to a fixing object passes. The fixing hole portion 25b of the substrate 25 communicates with the fixing hole portion 77a of the inverter case 73.

Although not shown, a hole communicating with the fixing hole portion 77a of the inverter case 73 is provided in the cover portion 90 covering the opening portion of the inverter case 73. Therefore, the inverter case 73 and the cover 90 are fastened together and integrally coupled via bolts that pass through the substrate 25.

(fixing member 30)

As shown in fig. 1 and 5, the base plate 25 has a fixing member 30, and the fixing member 30 is provided integrally with the base plate 25 and fixes the inverter case 73 at least in the axial direction. The fixing members 30 are located at both side end portions of the substrate 25 in a direction intersecting a direction in which the substrate 25 extends radially outward when viewed in the axial direction.

In the present embodiment, the fixing members 30 are provided at both ends of the substrate 25 in the X axis direction, and are provided at positions radially outside the cylindrical portion 14 and near the flange portion 25a located on the negative side of the cylindrical portion 14 in the Y axis direction. That is, the fixing members 30 are provided at two positions at both ends of the substrate 25 in the X-axis direction, and are provided at four positions in total. The fixing member 30 provided on one side of the substrate 25 in the X-axis direction and the fixing member 30 provided on the other side of the substrate 25 in the X-axis direction are arranged to face an imaginary line a intersecting the central axis J and extending in the Y-axis direction.

As shown in fig. 3 and 4, the fixing member 30 has calking portions 31 protruding from both side ends of the base plate 25. The caulking portion 31 is bent toward the other side (rear side) in the axial direction with respect to the substrate 25 and is bent into the recess 73e, thereby fixing the inverter case 73 to the substrate 25. The caulking portion 31 is bent into the recess 73e and contacts the surface 73e 1. Therefore, the inverter case 73 can be fixed to the substrate 25 at least in the axial direction by the caulking portion 31.

As shown in fig. 3, the clinch portion 31 may be in contact with the surface portion 73e1 in a state of being bent into the recess 73e, and the tip portion of the clinch portion 31 may be in a state of being further bent toward one side (front side) in the axial direction as shown by a broken line. In this case, the rattling of the inverter case 73 relative to the substrate 25 in the X-axis direction can be further suppressed.

Further, as shown in fig. 5, since the caulking portions 31 are provided at both end portions of the substrate 25 in the X-axis direction, when the inverter case 73 is fixed by the caulking portions 31, the inverter case 73 can be firmly fixed to the substrate 25 without rattling.

As shown in fig. 4, the clinch portion 31 is disposed in a state of being in contact with the surface portion 73e1 of the recess 73e at positions where the end portions on both sides in the width direction of the clinch portion 31 face the pair of side surface portions 73e2 of the recess 73e, respectively. Therefore, when the caulking portion 31 is bent into the recess 73e, the caulking portion 31 can be prevented from contacting the side surface portion 73e2 of the recess 73 e. Further, when the inverter case 73 is displaced in the Y-axis direction with respect to the substrate 25, the ends on both sides in the width direction of the caulking portion 31 contact the side surface portions 73e2 of the recessed portion 73e, and displacement of the inverter case 73 in the Y-axis direction can be suppressed.

(rotor 20)

As shown in fig. 2, the rotor 20 includes a rotor core 20a and a rotor magnet 20 b. The rotor core 20a surrounds the shaft 11 in the circumferential direction (θ direction) and is fixed to the shaft 11. Rotor magnet 20b is fixed to an outer surface of rotor core 20a along the circumferential direction (θ direction). The rotor core 20a and the rotor magnet 20b rotate together with the shaft 11. The rotor 20 may be an embedded magnet type in which a permanent magnet is embedded in the rotor 20. The embedded magnet type rotor 20 can reduce the magnet from being separated by a centrifugal force, and can actively use reluctance torque, compared to a surface magnet type in which permanent magnets are provided on the surface of the rotor 20.

(stator 22)

The stator 22 surrounds the rotor 20 in the circumferential direction (θ direction) and rotates the rotor 20 about the center axis J. The stator 22 includes a core back 22a, teeth 22c, coils 22b, and an insulator (bobbin) 22 d.

The core back 22a is cylindrical and concentric with the shaft 11. The tooth portion 22c extends from the inner side surface of the core back portion 22a toward the shaft 11. The plurality of teeth 22c are provided and arranged at equal intervals in the circumferential direction of the inner surface of the core back 22 a. The coil 22b is disposed around the insulator (bobbin) 22 d. An insulator (bobbin) 22d is attached to each tooth 22 c.

(shaft 11)

As shown in fig. 2, the shaft 11 extends along the central axis J and penetrates the motor portion 10. The front side (-Z side) of the shaft 11 protrudes from the motor section 10 and is supported by the bearing 17 to extend into the pump section 40. The rear side (+ Z side) of the shaft 11 protrudes from the rotor 20 and is supported by a bearing 16. Therefore, the rotor 20 is in a state of being supported at both ends

< Pump part 40 >

As shown in fig. 2, the pump section 40 is located on one axial side of the motor section 10, specifically, on the front side (-Z side). The pump section 40 is driven by the motor section 10 via the shaft 11. The pump section 40 has a pump rotor 47 and a pump housing 51. The pump housing 51 has a pump body 52 and a pump cover 57. Hereinafter, each member will be described in detail.

(Pump body 52)

The pump body 52 is fixed to the front side (-Z side) of the motor case 13 on the front side (-Z side) of the motor portion 10. The pump body 52 has a concave portion 54 that is recessed from a surface 52c on the rear side (+ Z side) toward the front side (-Z side). The bearing 17 and the seal member 18 are accommodated in the recess 54. The pump body 52 has a housing portion 53, and the housing portion 53 has a side surface 53a facing the circumferential surface of the pump rotor 47 and a bottom surface 53b located on the rear side (+ Z side) of the pump portion 40. The housing portion 53 is open on the front side (-Z side) and is recessed toward the rear side (+ Z side). The storage portion 53 has a circular shape when viewed from the axial direction.

As shown in fig. 2, the pump cover 57 covers the pump body 52 from the front side (-Z side), and the housing portion 53 is provided between the pump cover 57 and the pump body 52.

The pump body 52 has a through hole 55 penetrating along the center axis J. Both ends of the through hole 55 in the axial direction are opened to allow the shaft 11 to pass therethrough, the opening on the rear side (+ Z side) of the through hole 55 is opened at the recess 54, and the opening on the front side (-Z side) is opened at the housing portion 53. The through hole 55 functions as a sliding bearing 45 that rotatably supports the shaft 11.

As shown in fig. 1, a pump-side flange portion 52a that projects radially outward and extends in the axial direction is provided on the outer side surface of the pump body 52. The pump-side flange portion 52a is provided in plurality at intervals in the circumferential direction. The pump-side flange portion 52a is provided with a through hole (not shown) that penetrates in the axial direction. The pump body 52 is detachably fixed to the motor case 13 via bolts 56 inserted through the through holes.

(Pump cover 57)

As shown in fig. 1 and 2, the pump cover 57 has an end surface 58 provided on one side (front side) in the axial direction and a cylindrical side surface 61 connected to a peripheral edge portion of the end surface 58 and extending to the other side in the axial direction. An intake port 63 is provided on one of the end surface 58 and the side surface 61, and an exhaust port 64 is provided on the other of the end surface 58 and the side surface 61. In the present embodiment, the end surface 58 has a circular shape when viewed in the axial direction. The suction port 63 is provided on the end surface 58. The discharge port 64 is provided on the side face 61. The suction port 63 is disposed at a radial peripheral edge of the end surface, and the discharge port 64 is disposed at a position facing the suction port 63 with respect to the central axis J.

The suction port 63 has a circular shape when viewed in the axial direction. The discharge port 64 is formed in an elongated hole shape extending in the circumferential direction of the side surface 61. The opening area of the discharge port 64 is the same as that of the suction port 63. The opening area of the discharge port 64 may be slightly smaller than the opening area of the suction port 63. The discharge port 64 is disposed at a position having a predetermined distance from one axial end of the side surface 61 to the other axial end. A seal member 66 is annularly provided between the discharge port 64 and one axial end of the side surface 61, and the seal member 66 brings a supply oil passage for supplying oil to the suction port 63 into close contact with the side surface 61.

In the above embodiment, the case where the suction port is provided on the end surface and the discharge port is provided on the side surface is shown, but the present invention is not limited thereto. For example, the discharge port may be provided on the end face and the suction port may be provided on the side face. In this case, the relative positions of the suction port and the discharge port and the area of the opening are the same as those of the above embodiment.

(Pump rotor 47)

The pump rotor 47 is mounted on the shaft 11. In more detail, the pump rotor 47 is mounted on the front side (-Z side) of the shaft 11. The pump rotor 47 has an inner rotor 47a mounted on the shaft 11 and an outer rotor 47b surrounding a radially outer side of the inner rotor 47 a. The inner rotor 47a has an annular shape. The inner rotor 47a is a gear having teeth on the radially outer side.

The inner rotor 47a is fixed to the shaft 11. More specifically, an end portion of the shaft 11 on the front side (-Z side) is press-fitted inside the inner rotor 47 a. The inner rotor 47a rotates in the circumferential direction (θ direction) together with the shaft 11. The outer rotor 47b is annular and surrounds the radially outer side of the inner rotor 47 a. The outer rotor 47b is a gear having teeth on the radially inner side.

The inner rotor 47a and the outer rotor 47b are engaged with each other, and the outer rotor 47b is rotated by the rotation of the inner rotor 47 a. That is, the pump rotor 47 is rotated by the rotation of the shaft 11. In other words, the motor section 10 and the pump section 40 have the same rotational axis. This can suppress the size of the electric oil pump 1 in the axial direction from increasing

In addition, the volume between the meshing portions of the inner rotor 47a and the outer rotor 47b is changed by the rotation of the inner rotor 47a and the outer rotor 47 b. The area of reduced volume is the pressurized area and the area of increased volume is the negative pressure area. The suction port 63a is disposed on the rear side (+ Z side) of the negative pressure region of the pump rotor 47. Further, a discharge port 64a is disposed on the rear side (+ Z side) of the pressurized region of the pump rotor 47. Here, the oil sucked into the housing 53 from the suction port 63 provided in the pump cover 57 is housed in the volume portion between the inner rotor 47a and the outer rotor 47b, and is sent to the pressurization region. Then, the oil is discharged from the discharge port 64 through the discharge port 64 a.

< action and Effect of electric oil Pump 1 >

Next, the operation and effect of the electric oil pump 1 will be described. As shown in fig. 2, when the motor unit 10 of the electric oil pump 1 is driven, the shaft 11 of the motor unit 10 rotates, and the outer rotor 47b rotates as the inner rotor 47a of the pump rotor 47 rotates. When the pump rotor 47 rotates, the oil sucked from the suction port 63 of the pump section 40 moves in the housing section 53 of the pump section 40, passes through the discharge port 64a, and is discharged from the discharge port 64.

(1) Here, as shown in fig. 1, the pump cover 57 of the electric oil pump 1 of the present embodiment is provided with a suction port 63 on one of the end surface 58 and the side surface 61, and a discharge port 64 on the other of the end surface 58 and the side surface 61. Therefore, since the suction port 63 and the discharge port 64 are located at separate positions, it is not necessary to shift the positions of the suction port 63 and the discharge port 64 in the axial direction, as compared with a case where the suction port 63 and the discharge port 64 are disposed at close positions. Therefore, since the oil passage can be directly connected to each of the suction port 63 and the discharge port 64, an increase in the axial size of the electric oil pump 1 can be suppressed.

(2) The suction port 63 is disposed at a radial peripheral edge of the end surface 58, and the discharge port 64 is disposed at a position facing the suction port 63 with respect to the central axis J. Therefore, the relative positions of the suction port 63 and the discharge port 64 can be arranged at separate positions. Therefore, the work for connecting the oil passage to the suction port 63 and the discharge port 64 can be easily performed.

(3) The suction port 63 has a circular shape when viewed in the axial direction, and the discharge port 64 has an elongated hole shape extending in the circumferential direction of the side surface 61. Since the shapes of the suction port 63 and the discharge port 64 are different, it is possible to prevent an erroneous operation of erroneously connecting oil passages corresponding to the suction port 63 and the discharge port 64, respectively.

(4) The opening area of the discharge port 64 is the same as or slightly smaller than the opening area of the suction port 63. Therefore, when the oil sucked from the suction port 63 flows through the discharge port 64, the reduction of the pressure loss can be suppressed, and the flow rate of the oil flowing out of the discharge port 64 can be prevented from being reduced.

(5) A seal member 66 is annularly provided between the axial end of the side surface 61 and the discharge port 64, and the seal member 66 causes a supply oil path for supplying oil to the suction port 63 to be closely attached to the side surface. Therefore, an oil passage for supplying oil to the suction port 63 can be connected to the pump cover 57 in a state of being closely attached to the side surface 61. Therefore, air can be prevented from entering, and the flow rate of oil sucked into the suction port 63 can be prevented from decreasing.

While the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the present invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the invention described in the claims and equivalent ranges thereof.

The present application claims to be based on the priority of japanese patent application No. 2018-83415, which is a japanese patent application filed 24/4 in 2018, and the entire contents of the disclosure of the japanese patent application are cited.

Description of the reference symbols

1: an electric oil pump; 10: a motor section; 11: a shaft; 13: a motor housing; 20: a rotor; 22: a stator; 40: a pump section; 47: a pump rotor; 51: a pump housing; 52: a pump body; 53: a storage section; 57: a pump housing; 58: an end face; 61: a side surface; 63: a suction inlet; 64: an outlet port; 66: a sealing member; 73: an inverter case; j: a central axis.

Claims

1. An electric oil pump is characterized in that,

the electric oil pump includes:

a motor unit having a shaft centered on a central axis extending in an axial direction;

a pump section that is located on one axial side of the motor section and that discharges oil by being driven by the motor section via the shaft; and

an inverter unit that is located on the other axial side of the motor unit and is fixed to the motor unit,

the motor unit includes:

a rotor fixed to the other axial side of the shaft;

a stator located radially outward of the rotor; and

a motor case that houses the rotor and the stator,

the pump section includes:

a pump rotor attached to the shaft protruding from the motor unit to one axial side; and

a pump housing that is provided with a suction port that sucks in the oil and a discharge port that discharges the oil, and that houses the pump rotor,

the pump housing has:

a pump body having a housing portion that houses the pump rotor; and

a pump cover mounted on one axial side of the pump body,

the pump cover has:

an end surface provided on one side in the axial direction; and

a cylindrical side surface connected to the peripheral edge part of the end surface and extending toward the other axial side,

the suction port is provided in one of the end surface and the side surface, and the discharge port is provided in the other of the end surface and the side surface.

2. The electric oil pump according to claim 1,

viewed axially, the end faces are circular,

the suction inlet is arranged on the end surface,

the discharge port is arranged on the side surface,

the suction port is disposed at a peripheral edge portion on one side in the radial direction of the end surface,

the discharge port is disposed at a position facing the suction port with respect to the central axis.

3. The electric oil pump according to claim 2,

when viewed along the axial direction, the suction inlet is in a circular shape,

the discharge port is in the form of an elongated hole extending in the circumferential direction of the side surface.

4. The electric oil pump according to claim 3,

the opening area of the discharge port is the same as or slightly smaller than the opening area of the suction port.

5. The electric oil pump according to claim 4,

the discharge port is disposed at a position having a predetermined distance from one axial end of the side surface to the other axial end,

a seal member is provided in an annular shape between the end portion on one axial side of the side surface and the discharge port, and the seal member brings a supply oil passage for supplying the oil to the suction port into close contact with the side surface.