Electric pump

Abstract

To provide an electric pump that can be made smaller in diameter. [Solution] This electric pump includes a motor having a shaft rotatable about a central axis, a pump mechanism connected to one axial side of the shaft, a circuit board (40) located radially outwardly of the shaft, perpendicular to the axial direction, and a housing body capable of accommodating the motor and circuit board. The circuit board has a plate surface facing the shaft and extending along the axial direction. The housing body includes a motor housing (211), a board housing (213), a pump housing (212), and a mounting plate portion located radially outwardly of the shaft, perpendicular to the axial direction. The mounting plate portion has a mounting surface facing the shaft and extending along the axial direction. The motor and pump mechanism are located on the inner corner of the angle formed by the intersection of a third surface including the plate surface and a fourth surface including the mounting surface.

Description

Technical Field

[0001] The present invention relates to an electric pump.

Background Art

[0002] Conventionally, a configuration is known in which a heat sink is provided outside a motor unit, and power circuit components such as FETs are fixed to the heat sink with screws to dissipate heat generated by the power circuit components.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the motor unit of Patent Document 1, heat generated from the motor cannot be quickly dissipated, and there is a risk that the motor will break due to high temperature, a risk that the operating time in a high-output state cannot be lengthened, and a risk that the size of the motor will increase.

Means for Solving the Problems

[0005] According to one aspect of the present invention, The device comprises a motor having a shaft rotatable around a central axis, a pump mechanism connected to one axial side of the shaft, a circuit board located radially outward perpendicular to the axial direction of the shaft, and a housing capable of housing the motor and the circuit board. The circuit board has a first surface with electronic components and a second surface opposite the first surface, both facing the shaft and oriented axially. The housing has a motor housing portion for housing the motor, a circuit board housing portion for housing the circuit board, a pump housing portion for housing the pump mechanism, and a mounting plate portion located radially outward perpendicular to the axial direction of the shaft. The mounting plate portion has a mounting surface facing the shaft and oriented axially. The motor and the pump mechanism are located on the inner corner side of the intersection of a third surface including the plate surface and a fourth surface including the mounting surface.

Effects of the Invention

[0006] According to one aspect of the present invention, Miniaturization in the radial direction is possible. an electric pump is provided.

Brief Description of the Drawings

[0007] [Figure 1] Figure 1 is a cross-sectional view of the electric pump of the present embodiment. [Figure 2] Figure 2 is a perspective view showing the internal structure of the electric pump of the present embodiment. [Figure 3] Figure 3 is a perspective view showing the busbar unit of this embodiment. [Figure 4] Figure 4 is a cross-sectional view of the electric pump along the first connecting section. [Figure 5] Figure 5 is a partial cross-sectional view of the housing and motor. [Figure 6] Figure 6 is a perspective view showing the inside of the third recessed area. [Figure 7] Figure 7 shows the inside of the third accommodating recess as viewed from the negative side to the positive side in the Z direction. [Figure 8] Figure 8 is a cross-sectional view of a portion of the electric pump of this embodiment, taken in a direction intersecting the axial direction at the rear of the second connecting portion. [Figure 9] Figure 9 is a cross-sectional view of a portion of the electric pump of this embodiment, taken in a direction intersecting the axial direction, on the front side of the second connecting portion. [Figure 10] Figure 10 is a schematic diagram of the electric pump of this embodiment as viewed from the axial direction. [Figure 11] Figure 11 is a perspective view showing the external structure of the electric pump according to this embodiment. [Figure 12] Figure 12 is a schematic perspective view showing each of the flow paths in this embodiment. [Modes for carrying out the invention]

[0008] In the following description, an electric oil pump will be used as an example to illustrate this embodiment of the electric motor and electric pump. The electric oil pump of this embodiment is used to supply oil to equipment mounted on vehicles, etc.

[0009] In the drawings referenced below, the XYZ coordinate system is shown as a three-dimensional Cartesian coordinate system where appropriate. In the XYZ coordinate system, the X-axis direction is parallel to the axis direction of the central axis J shown in Figures 1 and 5. The central axis J is the central axis of the shaft 21 of the motor 220, which will be described later. The Y-axis direction is the direction perpendicular to the X-axis and parallel to the depth direction in Figures 1 and 5. The Z-axis direction is the direction perpendicular to both the X-axis and Y-axis directions, and is shown above in Figures 1 and 5. This direction is parallel to the downward direction. In the X, Y, and Z axes, the side indicated by the arrow in the diagram is considered the + side, and the opposite side is considered the - side.

[0010] In the following explanation, unless otherwise specified, the direction parallel to the central axis J (the X-axis direction) will simply be referred to as the "axial direction." The radial direction centered on the central axis J will simply be referred to as the "radial direction." The circumferential direction centered on the central axis J, that is, the direction around the axis of the central axis J (the θ direction), will simply be referred to as the "circumferential direction."

[0011] Furthermore, the positive side in the X-axis direction (+X side) is sometimes referred to as the "front side." Similarly, the negative side in the X-axis direction (-X side) is sometimes referred to as the "rear side." The front side (+X side) corresponds to one axial side in this invention. The rear side (-X side) corresponds to the other axial side in this invention.

[0012] The electric oil pump 200 of this embodiment will be described below with reference to Figures 1 to 12.

[0013] As shown in Figures 1 and 2, the electric oil pump 200 of this embodiment comprises a housing 210, a motor 220, a pump mechanism 30, and a circuit board 40. The housing 210 has a motor housing 211 (motor accommodating portion) that houses the motor 220, a pump housing 212 that houses the pump mechanism 30, a board housing 213 (circuit board accommodating portion) that houses the circuit board 40, a partition portion 330 that separates the motor housing 211 (motor accommodating portion) and the board housing 213 (circuit board accommodating portion), a convex portion 300 that protrudes from the partition portion 330, a connecting portion 310, and a board cover 241. The housing 210 is a housing body having the motor housing 211, the pump housing 212, the board housing 213, etc. In the case of the present embodiment, the motor housing 211 that is the motor accommodating portion, the pump housing 212, the board housing 213 that is the circuit board accommodating portion, the partition portion 330, and the convex portion 300 are parts of a single member.

[0014] The motor housing 211 which is the motor accommodating portion is located on the rear side (-X side) of the housing 210. The motor housing 211 is cylindrical and extends in the axial direction. The motor housing 211 has a first accommodating recess 211a formed by a recess that opens to the rear side. The first accommodating recess 211a is closed from the rear side by a bearing holder 226 described later.

[0015] The pump housing 212 is located on the front side (+X side) of the housing 210. The pump housing 212 has a second accommodating recess 212a formed by a recess that opens to the front side. The electric oil pump 200 has a pump cover 212b that closes the second accommodating recess 212a from the front side.

[0016] The board housing 213 which is the circuit board accommodating portion is located on the side surfaces of the motor housing 211 (motor accommodating portion) and the pump housing 212 arranged in the axial direction. The board housing 213 is located on the lower side (-Z side) in the drawing of the motor housing 211 and the pump housing 212. The board housing 213 is substantially rectangular when viewed from the outside in the radial direction. The board housing 213 has a shape with a long side in the axial direction and a short side in a direction intersecting the axial direction. The board housing 213 has a third accommodating recess 213a that opens toward the lower side in the drawing of the housing 210.

[0017] Housing 210 has a first through-hole 210a that axially connects the first housing recess 211a of the motor housing 211, which is the motor housing, and the second housing recess 212a of the pump housing 212. Housing 210 also has a second through-hole 210b that radially connects the first housing recess 211a and the third housing recess 213a of the circuit board housing 213, which is the circuit board housing. That is, the second through-hole 210b extends radially between the motor housing 211 and the circuit board housing 213 and is a housing that accommodates the joint busbars 251a to 251c, which will be described later. The above housing may be a groove that opens axially and extends radially.

[0018] The motor 220 comprises a rotor 22 having a shaft 21, a stator 23 having windings, a busbar assembly 224, a busbar cover 225, a bearing holder 226, a first bearing 27, and a second bearing 28. The front end of the shaft 21 is connected to the pump mechanism 30.

[0019] The stator 23 of the motor 220 is assembled to the housing 210 from the rear side (-X side) of the housing 210 by methods such as shrink fitting, press fitting, or insertion. Shrink fitting offers good assembly, and after assembly, the housing 210 holds the stator 23 around its entire circumference, resulting in good retention. In other words, the motor housing 211, which is the motor housing portion of the housing 210, and the stator 23 are in contact.

[0020] Alternatively, when assembling by insert (clearance fitting), a through hole may be provided on the radially outer side of the stator 23 and a screw hole in the axial direction of the housing 210, and the stator 23 may be inserted into the housing 210 (motor housing 211) and secured with bolts or the like. In this case, adhesive may be applied to fill the radial gap between the stator 23 and the housing 210 (motor housing 211) to improve the radial retention of the stator 23. In other words, the motor housing 211, which is the motor housing portion of the housing 210, and the stator 23 are connected via adhesive.

[0021] Alternatively, when assembling by insertion, the stator 23 may be pre-positioned using a jig to be closer to the circuit board 40 side (+Z side) (so that it is in contact with the motor housing 211 of the housing 210) before being screwed in.

[0022] The circuit board 40 is a control board that includes, for example, a motor drive circuit 451, a control unit 452 for controlling the motor drive, and a reverse connection prevention circuit 453. The circuit board 40 also includes a power input unit 454 and a motor power output unit 455. The circuit board 40 has a plurality of heat-generating components 43. The board surface of the circuit board 40 has a first surface 411 having the heat-generating components 43 and a second surface 412 opposite to the first surface 411.

[0023] In this embodiment, the circuit board 40 is a rectangular plate extending in the axial direction. In this embodiment, the circuit board 40 has a longer side in the axial direction and a shorter side in the direction intersecting the axial direction (Y-axis direction), and is a rectangle with rounded corners. The circuit board 40 is located radially outward from the motor 220 and the pump mechanism 30, and the surface of the circuit board 40 faces the motor 220 and the pump mechanism 30. In this embodiment, the circuit board 40 has a power input section 454 at its axial front end and a motor power output section 455 at its axial rear end.

[0024] The heat-generating components 43 include, for example, multiple transistors 431 and a microcontroller 432. The multiple transistors 431 constitute, for example, a motor drive circuit 451, and the microcontroller 432 controls the power supply to the motor drive circuit 451.

[0025] The heat-generating component 43 is soldered, for example, to the first surface 411 of the circuit board 40. The heat-generating component 43 has a metal surface 434 made of a metal plate that is soldered to the first surface 411 of the circuit board 40, and a resin surface 435 made of resin that is not soldered to the first surface 411 of the circuit board 40. When the metal surface 434 of the heat-generating component 43 is soldered facing the first surface 411 of the circuit board 40, the resin surface 435 on the opposite side of the metal surface 434 faces the same direction as the first surface 411 of the circuit board 40.

[0026] The circuit board 40 has through-holes 413 that penetrate from the first surface 411 to the second surface 412, which is the board surface opposite the first surface 411, in the area where the metal surface 434 of the heat-generating component 43 is soldered. The through-holes 413 have copper foil on the inner surface of the hole and around the opening of the through-holes 413 on the first surface 411 and the second surface 412. The copper foil is continuous and connected on the first surface 411 side and the second surface 412 side. The opening of the through-holes 413 on the first surface 411 and the inner surface of the through-holes 413, as well as the opening of the through-holes 413 on the second surface 412, can transfer heat from the heat-generating component 43 from the first surface 411 to the second surface 412 by the continuous copper foil. With this configuration, the circuit board 40 can dissipate heat from the heat-generating component 43 from the first side 411 (from the heat-generating component 43 itself) and also from the second side 412.

[0027] The circuit board 40 is mounted on the circuit board housing 213, which is the circuit board housing portion of the housing 210, with the heat-generating component 43 overlapping with the protrusion 300 of the housing 210 (described later), with the first surface 411 or the second surface 412 of the circuit board 40 facing the protrusion 300 side (motor 220 side). In other words, the heat-generating component 43 is positioned to overlap with the protrusion 300. When the first surface 411 is mounted facing the protrusion 300 side, the heat from the heat-generating component 43 can be transferred to the protrusion 300 by assembling it so that the resin surface 435 of the heat-generating component 43 is in contact with the protrusion 300. In other words, the heat from the heat-generating component 43 can be dissipated to the protrusion 300.

[0028] Furthermore, when the second surface 412 is mounted facing the protrusion 300, the circuit board 40 is assembled into the circuit board housing 213, which is the circuit board housing portion of the housing 210, so that the heat-generating component 43 and the protrusion 300 overlap. Because the heat-generating component 43 and the protrusion 300 overlap, the through-hole 413 in the area where the heat-generating component 43 is soldered is also assembled so that it overlaps with the protrusion 300. A heat dissipation member 51 may be placed between the second surface 412 of the circuit board 40 and the protrusion 300 during assembly.

[0029] As shown in Figure 6, the busbar assembly 224 has three busbars 224a, 224b, and 224c, and a resin busbar holder 224d that holds the busbars 224a to 224c. The busbar holder 224d is annular when viewed from the axial direction. The three busbars 224a to 224c are screwed to the rear-facing surface of the busbar holder 224d.

[0030] The busbar assembly 224 is located on the rear side of the stator 23. The busbar assembly 224 is inserted from the rear into the first housing recess 211a of the motor housing 211. One end of each of the three busbars 224a to 224c is connected to a coil wire 23d extending from coil 23c to the rear. The three busbars 224a to 224c extend from the connection point with the coil wire 23d toward the circuit board housing 213. The other ends of the three busbars 224a to 224c are positioned at the end of the busbar holder 224d toward the circuit board housing 213 (lower side in the diagram). The other ends of the three busbars 224a, 224b, and 224c are connected to three joint busbars 251a, 251b, and 251c, respectively, which will be described later.

[0031] The busbar cover 225 is located on the rear side of the busbar assembly 224, as shown in Figure 5. The busbar cover 225 is inserted into the first housing recess 211a from the rear side. The busbar cover 225 is annular when viewed from the axial direction. The busbar cover 225 covers the busbar assembly 224 from the rear side. The bearing holder 226 is placed over the busbar cover 225 from the rear side. The bearing holder 226 closes the first housing recess 211a from the rear side.

[0032] The busbar cover 225 has a stepped portion 225a on the outer peripheral edge of the surface facing the rear. The stepped portion 225a has a surface facing the rear and a surface facing radially outward. An elastic member 225b, which is an O-ring, is placed inside the stepped portion 225a. The elastic member 225b is sandwiched axially between the bearing holder 226 and the busbar cover 225. The bearing holder 226 pushes the busbar cover 225 towards the front via the elastic member 225b.

[0033] The busbar cover 225 functions as a spacer inserted between the busbar assembly 224 and the bearing holder 226. The busbar cover 225 is pushed forward by the elastic member 225b, thereby pushing the busbar assembly 224 forward. This configuration allows the busbar cover 225 to fix the busbar assembly 224 in the axial direction. The busbar cover 225 and the busbar assembly 224 may be part of a single component.

[0034] The bearing holder 226 is a disc-shaped member that covers the busbar cover 225 from the rear. The bearing holder 226 has a cylindrical portion 226a extending along the central axis J and a holder body 226b that extends radially outward from the outer circumferential surface of the cylindrical portion 226a. The cylindrical portion 226a has openings on both sides in the axial direction. The first bearing 27 is inserted into the front opening of the cylindrical portion 226a. The first bearing 27 is supported from the rear by a bearing support surface 226c located inside the cylindrical portion 226a.

[0035] The bearing holder 226 extends radially to the outside of the busbar cover 225. The bearing holder 226 is screwed to the housing 210 radially outward of the busbar cover 225. The breather 26b is inserted into the rear end of the cylindrical portion 226a.

[0036] The second bearing 28 is inserted from the rear into the first through hole 210a, which connects the first housing recess 211a and the second housing recess 212a. Inside the first through hole 210a, the oil seal 15, the fixing ring 16, the wave washer 17, and the second bearing 28 are arranged in order from the front.

[0037] The shaft 21 passes through the inner bore of the second bearing 28, wave washer 17, retaining ring 16, and oil seal 15. The pump mechanism 30 is connected to the front end of the shaft 21.

[0038] The busbar unit 250 connects the motor 220 and the circuit board 40. The busbar unit 250 is connected to the rear end of the circuit board 40. The busbar unit 250 is housed inside the second through hole 210b that connects the third housing recess 213a and the first housing recess 211a. Alternatively, the motor 220 and the circuit board 40 may be directly connected using three busbars 224a to 224c without using the busbar unit 250. For example, the three busbars 224a to 224c and a fixing member may be integrally molded from resin and screwed to the housing 210 at the fixing point of the fixing member. In this case, one end of the three busbars 224a to 224c may be connected to the coil wire 23d, and the other end of the three busbars 224a to 224c may pass through the second through hole 210b and be connected to the circuit board 40. With this configuration, the busbar holder 224d does not need to be annular when viewed from the axial direction. The annular shape of the resin busbar cover 225, when viewed from the axial direction, can be extended axially to form a cylindrical shape, thereby fulfilling the annular shape of the busbar holder 224d and separating the housing 210 from the busbars 224a to 224c.

[0039] One end of each joint busbar 251a to 251c extends from the joint busbar holder 252 toward the motor 220. The other end of each joint busbar 251a to 251c extends from the joint busbar holder 252 toward the circuit board 40.

[0040] The other ends of the three joint busbars 251a to 251c penetrate the circuit board 40 in the thickness direction. The other ends of the three joint busbars 251a to 251c are soldered to the wiring patterns on the circuit board 40. Alternatively, even when the motor 220 and the circuit board 40 are directly connected using three busbars 224a to 224c instead of the three joint busbars 251a to 251c, the other ends of the three busbars 224a to 224c may similarly penetrate the circuit board 40 in the thickness direction and be soldered to the wiring patterns on the circuit board 40.

[0041] The housing 210 further includes a plate-shaped mounting plate portion 70 for mounting the electric oil pump 200 to a mounting body, such as an oil pan in an automobile. The mounting plate portion 70 has a mounting surface 71 that extends in the axial direction, and the electric oil pump 200 is fixed to the mounting body by a fixing member with the mounting surface 71 in contact with the mounting body. In other words, the housing 210 has a mounting surface 71 that extends in the axial direction and contacts the mounting body. The housing 210 also includes a mounting plate portion 70 that extends in the axial direction and has a mounting surface 71. The mounting surface 71 does not need to continue continuously along the entire axial direction of the mounting plate portion 70, but may be composed of multiple sections. Examples of fixing members include bolts, press-fit pins, and rivets. In this embodiment, bolts are used as fixing members, taking into consideration ease of disassembly.

[0042] The mounting plate portion 70 is located on the side surfaces of the motor housing 211 (motor housing) and pump housing 212, which are aligned in the axial direction. The mounting plate portion 70 is located radially outward from the motor housing 211 and pump housing 212, which are aligned in the axial direction. The mounting plate portion 70 has a thickness in the direction away from the motor housing 211 and pump housing 212. The mounting surface 71 of the mounting plate portion 70 is furthest away from the motor 220 and pump mechanism 30 side (central axis J side) in the +Y axis direction through its thickness. The mounting surface 71 of the mounting plate portion 70 is not limited to the +Y axis direction through its thickness from the motor 220 and pump mechanism 30 side (central axis J side). For example, the mounting surface 71 of the mounting plate portion 70 may be provided in the -Y axis direction (see Figure 2), which is the motor 220 and pump mechanism 30 side (central axis J side). By positioning the mounting surface 71 that contacts the object to be mounted towards the central axis J, the electric oil pump 200 can be mounted to the object in such a way that the mounting plate portion 70 is positioned outside the electric oil pump 200, and the mounting plate portion 70 can play a role in protecting the motor and pump mechanism from adverse external influences. By providing columnar bosses or the like on the object to be mounted, it becomes possible to mount the object even if the mounting surface 71 on the mounting plate portion 70 is in the direction of the -Y axis, which is towards the central axis J.

[0043] The mounting plate portion 70 is positioned so that its mounting surface 71 and the board surfaces 411 and 412 of the circuit board 40 intersect. In other words, the mounting plate portion 70 and its mounting surface 71, and the board surfaces (411 or 412) of the circuit board housing 213 and the circuit board 40 are located on the sides of the motor housing 211 and the pump housing 212, which are aligned in the axial direction, and the mounting plate portion 70 and its mounting surface 71, and the board surfaces of the circuit board housing 213 and the circuit board 40 are in a positional relationship where they intersect each other. Therefore, the extended surface of the mounting surface 71 and the extended surface of the board surface of the circuit board 40 intersect. In this embodiment, as shown in Figures 10 and 2, the mounting plate portion 70 extends in the +Z direction, and the circuit board 40 extends in the -Y direction. If the mounting surface 71 and the board surfaces (411 or 412) of the circuit board 40 were to virtually extend each other or one of them, they would abut in the Z and Y directions, creating corners in the Z and Y directions. The motor 220 (motor housing 211) and the pump mechanism 30 (pump housing 212) are located on the inner corner β side of the corner formed by the virtual extension of the mounting surface 71 and the board surface (411 or 412) of the circuit board 40, either one or the other. In other words, the motor 220 (motor housing 211) and the pump mechanism 30 (pump housing 212) are located on the inner corner side of the corner where the third surface (a virtual extension of the mounting surface 71) and the fourth surface (a virtual extension of the board surface of the circuit board 40) intersect. Alternatively, the motor 220 (motor housing 211) and the pump mechanism 30 (pump housing 212) are located on the inner corner side of the corner where the third surface (a virtual extension of the mounting surface 71) and the board surface of the circuit board 40 intersect, or on the inner corner side of the corner where the fourth surface (a virtual extension of the board surface of the circuit board 40) intersects.

[0044] This configuration allows for radial miniaturization compared to a configuration where the mounting plate 70, motor 220, pump mechanism 30, and circuit board 40 are arranged in that order along the mounting surface 71, away from the mounting surface 71. It also allows for miniaturization compared to a configuration where the circuit board 40's surface is positioned in a direction intersecting the axial direction. For example, in a configuration where the control board, the circuit board 40, has its surface positioned in a direction intersecting the axial direction, the longer side of the circuit board 40 may be longer than the radial direction of the motor 220 and pump mechanism 30, making radial miniaturization impossible. If radial miniaturization is not possible, the electric oil pump 200, which is mounted on the oil pan of an automobile, may interfere with nearby automobile transmission or body-related components.

[0045] In this embodiment, the circuit board 40 has a power input section 454 at its axial front end and a motor power output section 455 at its axial rear end. Power input to the power input section 454 located at the axial front end of the circuit board 40 is output from the motor power output section 455 located at the axial rear end of the circuit board 40 via a circuit board wiring pattern provided on the circuit board 40. In other words, power is input to the circuit board wiring pattern at the axial front end of the circuit board 40, and then output from the axial rear end of the circuit board 40 toward the busbar of the motor 220. In this configuration, the following circuit board wiring pattern can be adopted for the circuit board 40. That is, the circuit board wiring pattern does not provide a route for the power input to the power input section 454 to return from the axial rear side to the front side in the process leading to the motor power output section 455, or minimizes such a route. Therefore, with the electric oil pump 200, compared to a configuration where the motor power output unit 455 is located at a different location from the axial rear end of the circuit board 40, the total length of the circuit board wiring pattern can be shortened, thereby reducing the size (area) of the circuit board 40. Since there is no route to return from the axial rear to the front, a circuit board wiring pattern is not required in the short-side direction (Y-axis direction) of the circuit board 40, so the short-side direction (second short-side direction) of the circuit board 40 can be made smaller, and the electric oil pump 200 as a whole can be made smaller in the radial direction. By arranging the long side of the circuit board 40 in the axial direction and placing it on the side of the motor 220 and pump mechanism 30 which are aligned in the axial direction, the electric oil pump 200 can be made smaller in the radial direction.

[0046] When viewed horizontally in the axial direction from the mounting surface 71 side of the mounting plate portion 70, the mounting plate portion 70 is smaller than the motor housing 211 and the pump housing 212 in the direction intersecting the axial direction (Z direction). With this configuration, the mounting plate portion 70 does not protrude outward beyond the outer dimensions of the motor housing 211 and the pump housing 212, thus enabling the electric oil pump 200 to be made smaller in the radial direction.

[0047] The mounting plate portion 70 has at least two mounting holes 721 and 722, which are located axially outward from the pump housing 212 and axially outward from the motor housing 211. In addition, the mounting holes 721 and 722 are located in the Z direction between the substrate housing 213, the motor housing 211 and the pump housing 212. This configuration allows for a smaller size in the radial direction because the mounting holes 721 and 722 do not protrude radially outward.

[0048] The mounting plate portion 70 has an intake port 731 for drawing in the fluid drawn in and discharged by the pump mechanism 30, an outlet port 734 for discharging the fluid, and a fluid passage 73 in the axial range from the front mounting hole 721 (first mounting hole 721) to the rear mounting hole 722 (second mounting hole 722). With this configuration, the mounting plate portion 70 has an intake port 731, an outlet port 734, and a fluid passage 73, so it can be made smaller compared to a structure in which the intake port 731, outlet port 734, and fluid passage 73 are located around the mounting plate portion 70.

[0049] The mounting plate portion 70 has an intake port 731 and an outlet port 734 in the axial range from the first mounting hole 721 to the second mounting hole 722. In this configuration, since the intake port 731 and the outlet port 734 are located in the axial range between the first mounting hole 721 and the second mounting hole 722, which are located axially outward from the motor housing 211 and axially outward from the pump housing 212, the intake port 731 and the outlet port 734 are not located axially outward from the mounting holes 721 and 722, resulting in a compact design in the axial direction.

[0050] The mounting plate portion 70 further has a front mounting hole 723 (third mounting hole 723). When viewing the mounting surface 71 from the front, the third mounting hole 723 is offset from the first mounting hole 721 in the radial direction (Z direction) of the central axis J. The presence of the third mounting hole 723 in the mounting plate portion 70 improves the fixing to the object to be mounted, and stabilizes the fixing of the electric oil pump 200. Because the fixing at three locations, from the first to the third mounting holes, improves and stabilizes the fixing of the electric oil pump 200, the fixing of the suction port 731 and discharge port 734 to the object to be mounted is also improved and stabilized. The mounting plate portion 70 has a suction port 731 and a discharge port 734 in the radial direction (Z direction) range from the first mounting hole 721 to the third mounting hole 723. In this configuration, a mounting plate 70 is located in the Z direction between the substrate housing 213 and the motor housing 211 and pump housing 212. Since the mounting plate portion 70 has an intake port 731 and an outlet port 734 in the radial direction (Z direction) from the first mounting hole 721 to the third mounting hole 723, it can be made smaller in the radial direction compared to a case where the intake port 731 and outlet port 734 are located radially outward from the mounting holes 721 and 723. Furthermore, the mounting plate portion 70 is smaller because the intake port 731 and outlet port 734 do not protrude in the Z direction beyond its outer shape.

[0051] When viewed from the mounting surface 71 side (viewing from the + side to the - side in the Y direction), the intake port 731 and the discharge port 734 are offset from each other in the axial direction. In this embodiment, the intake port 731 is located axially rearward than the discharge port 734. Furthermore, when viewed with the + side in the Z direction facing upward, the intake port 731 is located lower in the Z direction than the discharge port 734. This configuration makes it possible to reduce the size in the radial direction compared to a case where the intake port 731 and the discharge port 734 are located in the same axial direction and are arranged in order from the lower Z direction.

[0052] In this embodiment, the mounting surface 71 does not need to be continuous over the entire mounting plate portion 70 and may be partially formed. The mounting surface 71 may be only in the area that contacts the object to be mounted. The mounting surface 71 may be formed only around, for example, the first mounting holes 721 to the third mounting holes 723 and the intake port 731 and discharge port 724. The mounting surface 71 may also be present around the positioning location.

[0053] The mounting surface 71 may have an intake surface portion 715 around the intake port 731 and an outlet surface portion 716 around the outlet port 734. By arranging the intake port 731 and intake surface portion 715 and the outlet port 734 and outlet surface portion 716 offset from each other in the axial direction, the radial size can be reduced compared to the case where the intake port 731 and intake surface portion 715 and the outlet port 734 and outlet surface portion 716 are arranged side by side in the Z direction at the same location in the axial direction.

[0054] The flow path 73 has an intake-side flow path 732 and a discharge-side flow path 733. The intake-side flow path 732 includes, for example, a first intake flow path 7321 extending from the intake port 731 toward the pump mechanism 30 in a direction intersecting the axial direction, a third intake flow path 7323 extending from the pump mechanism 30 and the pump housing 212 toward the mounting plate portion 70, and a second intake flow path 7322 connected to the first intake flow path 7321 and the third intake flow path 7323. The discharge-side flow path 733 also includes, for example, a first discharge flow path 7331 extending from the pump mechanism 30 and the pump housing 212 toward the mounting plate portion 70. The discharge-side flow path 733 may have only one or more. In this embodiment, the flow path 73 has a relief flow path 735 that branches off from the first discharge flow path 7331 and connects to the first intake flow path 7321 at a position away from the second intake flow path 7322. The relief passage 735 is a passage for the fluid discharged by the pump mechanism 30 to return to the suction passage 732. In this embodiment, the relief passage 735 has a passage that runs along the axial direction and a passage that runs in a direction intersecting the axial direction. In this embodiment, the third suction passage 7323 is the final suction passage that connects to the pump mechanism 30 and the pump housing 212 in the passage (path) from the suction port 731 to the pump mechanism 30. The final suction passage is not limited to the third suction passage 7323.

[0055] The third suction passage 7323 (final suction passage 7323) and the first discharge passage 7331 are connected to the mounting plate 70 and the pump housing 212 along their respective passages. In this embodiment, the final suction passage 7323 and the first discharge passage 7331 are connected in a straight line from the mounting plate 70 to the pump housing 212. The final suction passage 7323 and the first discharge passage 7331 are formed from the mounting surface 71 side, for example, by mold forming or machining. Because the final suction passage 7323 and the first discharge passage 7331, which connect to the pump housing 212, are in a straight line, resistance when the pump mechanism 30 draws in and discharges fluid is suppressed, and a decrease in pump performance can be suppressed. Also, because the final suction passage 7323 and the first discharge passage 7331, which connect to the pump housing 212, are in a straight line, the housing 210 is easy to manufacture.

[0056] The third intake passage 7323 is created by machining from the mounting surface 71 side of the mounting plate portion 70 using a drill or the like. At this time, the opening made in the mounting plate portion 70 is fitted with a lid member or cap member by press-fitting or screw fitting in order to seal the connection between the third intake passage 7323 and the outside.

[0057] The third intake passage 7323 is located axially forward of the intake port 731 and the mounting surface (intake surface portion) 715 surrounding the intake port, and downward in the Z direction of the discharge port 734. With this configuration, the third intake passage 7323 (final intake passage 7323), which does not require a mounting surface, can be placed in the area of ​​the mounting plate portion 70 between the axial front of the intake port 731 and the mounting surface (intake surface portion) 715 surrounding the intake port, and downward in the Z direction of the discharge port 734. As a result, even if the discharge port 734 and the third intake passage 7323 (final intake passage 7323) are placed in close proximity in the axial direction, the mounting plate portion 70 can be made smaller in the Z direction. In other words, it can be made smaller in the radial direction. Furthermore, as mentioned above, since the third suction passage 7323 (final suction passage 7323) and the first discharge passage 7331 are connected in a straight line to the pump housing 212, there is no need to make the pump housing 212 a complex shape, and the pump housing 212 and housing 210 can be made smaller in the axial and radial directions. The third suction passage 7323 (final suction passage 7323) does not need to be in the exact same axial position as the discharge port 734, and may be offset axially from the center of the discharge port 734. The position of the third suction passage 7323 (final suction passage 7323) may be adjusted as appropriate, taking into consideration the structure inside the housing 210 or the performance of the pump mechanism 30.

[0058] In this embodiment, the second suction passage 7322 and the relief passage 735 extend along the axial direction, are offset (in the Z direction) from the substrate housing 213 side towards the motor housing 211 and pump housing 212 side, and are arranged so that they overlap each other at least partially in the radial direction (Y direction). This configuration allows for miniaturization in the radial direction. In other words, because the second suction passage 7322 and the relief passage 735 provided on the mounting plate portion 70 overlap in the Z direction, the thickness of the mounting plate portion 70 in the Y direction can be reduced, thus enabling miniaturization in the radial direction. Since the mounting plate portion 70 can be miniaturized by reducing its thickness, the length from the mounted object to the outer shape of the electric oil pump 200 can be shortened, contributing to the overall miniaturization of the mounted object and suppressing interference with components that may be present around the electric oil pump 200. Furthermore, because the mounting plate portion 70 can be made thinner, the distance that the electric oil pump 200 protrudes from the mounted object in the direction perpendicular to the mounting surface 71 is shortened. Because the protruding distance of the electric oil pump 200 is short, the moment related to the protruding distance and the weight of the electric oil pump 200 is small, which reduces vibration and noise when the electric oil pump 200 is operating, and also reduces the impact on the electric oil pump 200 from vibrations from the mounting body.

[0059] In this embodiment, the electric oil pump 200 has a connector portion 2135 that extends axially from the front side of the substrate housing 213. The connector portion 2135 is the point that connects the electric oil pump 200 to the outside. As shown in Figures 4 and 6, the connector portion 2135 has terminals that connect to a power input portion 454 (not shown) at the axial front end of the circuit board 40. The part of the connector portion 2135 that accepts external connections is located between the substrate housing 213 and the motor housing 211 and pump housing 212. In other words, in the Z direction, the connector portion 2135 is located between the substrate 213 and the motor housing 211 and pump housing 212. This configuration allows for radial miniaturization compared to the case where the connector portion 2135 is arranged away from the substrate housing 213 relative to the motor housing 211 and pump housing 212 in the Z direction.

[0060] The housing 210 has a partition wall 330 between the motor housing 211, which houses the motor, and the circuit board housing 213, which houses the circuit board. The partition wall 330 separates the motor housing 211 and the circuit board housing 213 and is in contact with the outer circumference of the stator 23 of the motor 220. The partition wall 330 has thickness in the direction away from the stator 23, and the side opposite to the stator 23 is on the inside of the circuit board housing. The partition wall 330 extends from the stator 23 toward the pump housing 212. The partition wall 330 does not extend in part on the rear side and is in the region of the second through hole 210b that connects the third housing recess 213a and the first housing recess 211a. The cross-sectional shape of the partition wall 330, when viewed from the axial direction, is arc-shaped along the stator 23.

[0061] The housing 210 has a protrusion 300 that projects from the partition wall 330 toward the circuit board 40. The protrusion 300 is positioned to overlap radially between the stator 23 of the motor 220 and the heat-generating component 43 of the circuit board 40.

[0062] When the second surface 412 of the circuit board 40 is assembled with the protrusion 300 facing it, the following components are in contact in the order radially outward from the central axis J: the stator 23 of the motor 220, the protrusion 300 (including the partition wall 330), the heat dissipation member 51, the circuit board 40, and the heat-generating component 43.

[0063] The protrusion 300 is, for example, a table-like shape and is roughly rectangular when viewed from the opening side (-Z direction) of the substrate housing 213. The end of the protrusion 300 on the circuit board 40 side has a surface shape that follows the second surface 412 of the circuit board 40.

[0064] The protrusion 300 has a first protrusion 301 that protrudes from the rear side of the motor 220 and a second protrusion 302 that protrudes from the front side of the motor 220. The first protrusion 301 and the second protrusion 302 are aligned in the axial direction and are positioned within the axial range of the motor. For example, the first protrusion 301 is located on the rear side of the motor 220 so as to overlap with the motor 220 and the heat-generating component, the transistor 431. For example, the second protrusion 302 is located on the front side of the motor 220 so as to overlap with the motor 220 and the heat-generating component, the microcontroller 432.

[0065] The first protrusion 301 is, for example, rectangular in shape with its longer side in the axial direction, and extends along the axial direction. The second protrusion 302 is, for example, roughly square.

[0066] The circuit board housing 213, which is the circuit board housing portion of the housing 210, has a wall portion 320 that surrounds the circuit board 40. The wall portion 320 has surfaces in a direction that intersects with the surface of the circuit board 40 and in a direction that is parallel to the surface of the circuit board 40. The wall portions 321 and 322 that intersect with the surface of the circuit board 40 stand in the -Z direction so as to encircle the thickness of the circuit board 40. The wall portion 323 that is parallel to the surface of the circuit board 40 extends axially towards the front, for example, so as to face the surface of the circuit board 40. The outside of the wall portion 320 is the outside of the electric oil pump 200, and the wall portion as seen from the outside has an outer surface. In other words, the wall portion 320 faces both the inside of the circuit board housing 213, which is the circuit board housing portion, and the outside of the electric oil pump 200.

[0067] The wall portion 320 of the substrate housing 213 has two wall portions 321 that have a surface along the axial direction, and two wall portions 322 that intersect with the axial direction.

[0068] The wall portion 320 of the substrate housing 213 has a wall portion 322 that connects to the corners (ends) of the wall portion 321 which has a surface aligned with the axial direction. The wall portion 320 of the substrate housing 213 has a wall portion 321 that connects to the corners (ends) of the wall portion 322 which intersects with the axial direction.

[0069] (There is a third protrusion) The protrusion 300 has a third protrusion 303 between the first protrusion 301 and the wall portion 320. The third protrusion 303 is located, for example, in a direction intersecting the axial direction (Y-axis direction) from the first protrusion 301. The third protrusion 303 is located between the first protrusion 301 and the wall portion 320 and protrudes from the partition wall portion 330. The shape of the third protrusion 303 is similar to that of the first protrusion 301, being trapezoidal and roughly rectangular when viewed from the opening side (-Z direction) of the substrate housing 213. If the height of the protrusion 300 is taken as the direction from the partition wall portion 330 to the circuit board 40 side (-Z direction), then the end of the third protrusion 303 on the circuit board 40 side is located at the same height as, for example, the end of the first protrusion 301 on the circuit board 40 side.

[0070] In a cross-section viewed from the axial direction, the partition wall portion 330 is arc-shaped with respect to the central axis J. In a cross-section viewed from the axial direction, the outer side of the partition wall portion (wall side) is lower in the height direction of the protrusion 300 the closer it is to the wall portion 330. In this embodiment, the first protrusion 301 protrudes from the center of the partition wall portion 330 in a cross-section viewed from the axial direction, and the third protrusion 301 protrudes from the space between the first protrusion 301 and the wall portion 320 of the partition wall portion 330 in a cross-section viewed from the axial direction. With this configuration, the height of the third protrusion 303 is higher than the height of the first protrusion 301. Since the first protrusion 301 and the third protrusion 303 have similar external shapes, the third protrusion 303 has a larger volume than the first protrusion 301 because it is taller.

[0071] In this embodiment, the first protrusion 301 is located in the center of the partition wall 330 in a cross-section viewed from the axial direction. The third protrusion 303 is located to the left and right of the first protrusion 301 in a cross-section viewed from the axial direction. The first protrusion 301 and the third protrusion 303 are both roughly rectangular when viewed from the opening side (-Z direction) of the substrate housing 213, and have the same length extending in the axial direction.

[0072] The protrusion 300 further has a fourth protrusion 304 that protrudes from the front wall portion 323. The fourth protrusion 304 overlaps radially with the pump mechanism 30 when viewed from the opening side (-Z direction) of the substrate housing 213. This configuration allows the heat transferred to the fourth protrusion 304 to be transferred to the fluid that the pump mechanism 30 inhales and discharges. Therefore, the heat generated by the heat-generating component 43 (transistor 431 used in the reverse connection prevention circuit 453) that has been transferred to the third connecting portion 313 can be dissipated into the fluid.

[0073] (There is a connecting part) The housing 210 has a connecting portion 310 that connects the protrusion 300 and the wall portion 320. The connecting portion 310 connects the protrusion 300 and the wall portion 320. In this embodiment, the connecting portion 310 is plate-shaped, protruding from the partition wall portion 330 toward the circuit board 40, and having surfaces in a direction that intersects or follows the axial direction. The connecting portion 310 does not necessarily have to be connected to the partition wall portion 330.

[0074] (1st connection part) The connecting portion 310 has a first connecting portion 311 extending in the axial direction and a second connecting portion 312 extending in a direction intersecting the axial direction. In this embodiment, the first connecting portion 311 extends in the axial direction from the front side of the first protrusion 301 and connects the first protrusion 301 and the fourth protrusion 304. A second protrusion 302 is located between the first protrusion 301 and the fourth protrusion 304 of the first connecting portion 311. The second protrusion 302 is connected to the first protrusion 301 and the fourth protrusion 304 by the first connecting portion 311.

[0075] (2nd connection part) In this embodiment, the second connecting portion 312 extends from the first protrusion 301 in a direction intersecting the axial direction (Y-axis direction) and connects the first protrusion 301 to the wall portion 321 having a surface aligned with the axial direction. A third protrusion 303 is located between the first protrusion 301 and the wall portion 321 having a surface aligned with the axial direction of the second connecting portion 312. The third protrusion 303 is connected to the first protrusion 301 and the wall portion 321 having a surface aligned with the axial direction by the second connecting portion 312. The second connecting portion 312 linearly connects the first protrusion 301 and the third protrusion 303 from one wall portion 321 to the other wall portion 321 in a direction intersecting the axial direction (Y-axis direction).

[0076] The connecting portion 310 further includes a third connecting portion 313 extending from the first connecting portion 311 in a direction intersecting the axial direction and connecting to the wall portion 320, and a fourth connecting portion 314 extending from the second connecting portion 312 in the axial direction and connecting to the wall portion 320.

[0077] The third connecting portion 313 extends along a direction intersecting the axial direction and connects the first connecting portion 311 to the wall portion 321 having a surface aligned with the axial direction. The third connecting portion 313 linearly connects one side of the wall portion 321 having a surface aligned with the axial direction to the other side. When viewed from the axial direction, if the height is defined as the direction from the partition wall portion 330 to the circuit board 40 side (-Z direction), the third connecting portion 313 has a stepped shape in which the height changes.

[0078] The third connecting portion 313 is located, for example, on the front side. At least a portion of the third connecting portion 313 overlaps radially with the pump housing 212 when viewed from the opening side (-Z direction) of the substrate housing 213. The housing 210 has a flow path 31 through which the fluid drawn in and discharged by the pump mechanism 30 flows, and the outer wall of the flow path 31 is inside the third housing recess 213a of the substrate housing 213. At least a portion of the third connecting portion 313 protrudes from the outer wall of the flow path 31. This configuration allows heat transferred to the third connecting portion 313 to be transferred to the outer wall of the flow path 31. Since fluid flows inside the flow path 31, the heat received by the outer wall of the flow path 31 can be transferred to the fluid flowing inside the flow path 31. In other words, the heat from the heat-generating component 43 and the motor 220 transferred to the third connecting portion 313 can be dissipated into the fluid.

[0079] The fourth connecting portion 314 extends along the axial direction and connects the second connecting portion 312 to the wall portion 322 having a surface that intersects with the axial direction. The fourth connecting portion 314 linearly connects one side of the wall portion 322 having a surface that intersects with the axial direction to the other side (from the front side to the rear side). The fourth connecting portion 314 is located between the third protrusion 303 and the wall portion 321 having a surface that aligns with the axial direction, and extends linearly from the front side to the rear side in the axial direction. In addition, a part of the fourth connecting portion 314 is connected to the wall portion 321 (323) having a surface that aligns with the axial direction on the front side of the substrate housing 213.

[0080] The connecting portion 310 further includes a fifth connecting portion 315 that connects the second protrusion 302 to the wall portion 321 having a surface aligned with the axial direction. The fifth connecting portion 315 extends from the second protrusion 302 in a direction intersecting the axial direction (Y-axis direction) and connects one side of the wall portion 321 having a surface aligned with the axial direction to the other side.

[0081] In this embodiment, the circuit board housing 213 is the circuit board housing portion of the housing 210. It has a longer side (first longer side) in the axial direction and a shorter side (first shorter side) in the direction intersecting the axial direction (Y-axis direction), and is a substrate housing. The circuit board 40 is roughly rectangular when viewed from the opening side (-Z direction) of 213. The circuit board 40 has a long side (second long side) in the axial direction and a short side (second short side) in the direction intersecting the axial direction (Y-axis direction), and is rectangular in shape. The circuit board 40 enters the circuit board housing 213 through the opening of the circuit board housing 213 and is fixed to the motor 220, pump mechanism 30, and partition wall 330 side from the opening side of the circuit board housing 213 with screws 2134. The circuit board housing 213 has screw holes 2133 for fastening the screws 2134 that fix the circuit board 40. In this embodiment, the screw holes 2133 of the circuit board housing 213 are formed in a cylindrical portion 2132 that protrudes from the partition wall 330 to the opening side of the circuit board housing 213.

[0082] In this embodiment, the first to fifth connecting portions 311 to 315 are lattice-shaped when viewed in the +Z direction from the opening side of the substrate housing 213. As shown in Figure 7, when the axial direction is vertical, in the substrate housing 213, which is the circuit board housing, the first connecting portion 311 extends axially near the center and connects to the first and second protrusions 301 and 302 which overlap with the motor 220, and to the fifth protrusion 305 which overlaps with the pump mechanism 30. The fourth connecting portion 314 extends axially between the third protrusion 303 and the wall portion 320 and connects from one side of the wall portion 322 which has a surface that intersects with the axial direction to the other. The second connecting portion 312, the third connecting portion 313, and the fifth connecting portion 315 intersect with the one first connecting portion 311 and the two fourth connecting portions 314 which extend axially, and connect from one side of the wall portion 321 which has a surface that aligns with the axial direction to the other. Between the first connecting portion 311 and the second connecting portion 312, the distance from the first protrusion 301 and the second protrusion 302 to the wall portion 320 is shorter for the second connecting portion 312.

[0083] The cylindrical portion 2132 is provided in the wall portion 320, or in the middle of the first connecting portion 311 to the fifth connecting portion 315, or at a point where any of the first connecting portion 311 to the fifth connecting portion 315 intersects with each other.

[0084] <Effects> The protrusion 300 of the housing 210 overlaps with the motor 220 and the heat-generating component 43 of the circuit board 40 as follows: When the second surface 412 of the circuit board 40 is assembled to the board housing 213 facing the motor 220 and the pump mechanism 30, the motor 220, the protrusion 300, the heat dissipation member 51, the circuit board 40, and the heat-generating component 43 are in contact in the following order, radially outward from the central axis J. Also, when viewed from a cross section along the axial direction, the motor 220, the protrusion 300, and the heat-generating component 43 overlap radially (radially outward from the central axis J). Furthermore, when viewed from a cross section perpendicular to the axial direction, the motor 220, the protrusion 300, and the heat-generating component 43 overlap radially (radially outward from the central axis J). The motor 220, the protrusion 300, and the heat-generating component 43 do not need to have their central points overlapping when viewed from a cross-section along the axial direction or from a cross-section perpendicular to the axial direction; even if their central points do not coincide, it is sufficient if at least a portion of them overlap. With this configuration, the protrusion 300 receives the heat from the heat-generating component 43 and the motor 220, and can dissipate the heat from both the heat-generating component 43 and the motor 220. The heat-generating protrusion 300 can dissipate heat outward from the side that is not in contact with the heat-generating component 43. Because the protrusion 300 dissipates heat from both the heat-generating component 43 and the motor 220, it has excellent heat dissipation. Because of the excellent heat dissipation, for example, the motor 220 can operate at high output for a longer period of time. Also, it is possible to operate at high output without increasing the size of the motor 220. If heat dissipation is not good, for example, the heat-generating component 43 or the motor 220 may reach the upper limit of their specified temperature and break down.

[0085] Alternatively, the circuit board 40 may be assembled to the board housing 213 with its first surface 411 facing the motor 220 and the pump mechanism 30. In this case, in a cross-section viewed from the axial direction, the motor 220, the protrusion 300, and the heat-generating component 43 are in contact with and overlap in the order radially outward from the central axis J. The protrusion 300 is in contact with the resin surface 435 of the heat-generating component 43, which faces the same direction as the first surface of the circuit board 40. Furthermore, a heat dissipation member 51 may be placed between the protrusion 300 and the heat-generating component 43.

[0086] The housing 210 may be made of metal or resin. If the housing 210 is made of metal, for example, a heat dissipation member 51 made of silicone can be used, and this heat dissipation member 51 can be sandwiched between the second surface 412 of the circuit board 40 and the protrusion 300 of the housing 210 to insulate the circuit board 40 from the housing 210. If the housing 210 is made of resin, it does not need to be made of a single piece, and may be integrally molded with a metal piece as appropriate. The motor housing 211 and the circuit board housing 213 may be made of resin, and the pump housing 212 may be made of metal, and the housing 210 may be integrally molded. Alternatively, only the protrusion 300 may be made of metal or resin.

[0087] The housing 210 has a connecting portion 310 that connects the protrusion 300 and the wall portion 320. The presence of the connecting portion 310 allows the heat received by the protrusion 300 from the heat-generating component 43 and the motor 220 to be dissipated to the wall portion 320 via the connecting portion 310. Since the wall portion 320 has an outer surface facing the outside of the housing 210, the heat transmitted from the connecting portion 310 can be dissipated to the outside of the outer surface. In other words, the heat from the heat-generating component 43 and the motor 220 can be dissipated from the electric oil pump 200 to the outside. The outer surface of the housing 210 (electric oil pump 200) can vary depending on the mounting environment, including mating components such as the object to be mounted, outside air (air, gas, etc.), oil (cooling oil, lubricating oil, grease), and other fluids. The heat transferred to the wall portion 320 is dissipated to the mating component, the outside air, oil, or other fluids, and the heat generated between the heat-generating component 43 and the motor 220 can be dissipated from the electric oil pump 200.

[0088] The housing 210 has a partition wall 330 that separates the motor housing 211, which houses the motor, and the circuit board housing 213, which houses the circuit board. The partition wall 330 is in contact with the outer circumference of the stator 23 of the motor 220. The partition wall 330 is in contact with the motor 220 along its entire axial direction. The protrusion 300 and the connecting portion 310 that protrude from the partition wall 330 are connected in the axial direction, allowing the heat of the motor 220 to be received along its entire axial direction, resulting in excellent heat dissipation.

[0089] The connecting portion 310 has a first connecting portion 311 extending axially from the protrusion 300 and a second connecting portion 312 extending in a direction intersecting the axial direction from the protrusion 300. This configuration allows heat to be transferred to multiple locations on the wall portion 320. Because heat can be transferred to multiple locations on the wall portion 320, heat dissipation is excellent. Furthermore, because the first connecting portion 311 extending axially overlaps with the motor 220, the heat from the motor 220 is dissipated not only to the protrusion 300 but also to the first connecting portion 311, allowing for even greater heat dissipation. In addition, because the second connecting portion 312 also overlaps with the motor 220, the heat from the motor 220 is dissipated to the second connecting portion 312, allowing for even greater heat dissipation. The first connecting portion 311, which extends in the axial direction, dissipates heat to the wall portion 322, which has a surface intersecting the axial direction, and the second connecting portion 312, which extends in a direction intersecting the axial direction, dissipates heat to the wall portion 321, which has a surface along the axial direction. Therefore, because the housing 210 has the first connecting portion 311 and the second connecting portion 312, heat can be dissipated throughout the entire wall portion 320, resulting in superior heat dissipation.

[0090] The protrusion 300 has a first protrusion 301 that protrudes from the rear side of the partition wall 330, and a second protrusion 302 that protrudes from the partition wall 330 on the front side of the first protrusion 301. The circuit board 40 has a motor power output section 455 at its axial rear end, and a motor drive circuit 451 and a control section 452 are arranged in order from the motor power output section 455 toward the front. In this embodiment, the first protrusion 301 receives heat from the transistor 431 that constitutes the motor drive circuit 451, and the second protrusion 302 receives heat from the microcontroller 432 that controls the power supply to the motor drive circuit 451. Because there are multiple protrusions 300, multiple heat-generating components 43 attached to the circuit board 40 can each dissipate heat to the first protrusion 301 and the second protrusion 302, resulting in excellent heat dissipation.

[0091] Furthermore, as shown in Figure 5, the first protrusion 301 and the second protrusion 302 are arranged side by side in the axial direction and overlap with the motor 220. Since not only the first protrusion 301 but also the second protrusion 302 overlaps with the motor 220, the motor 220 can dissipate heat to the first protrusion 301 and the second protrusion 302, resulting in excellent heat dissipation.

[0092] The protrusion 300 further has a third protrusion 303 between the first protrusion 301 and the wall portion 320. As shown in Figure 8, the third protrusion 303 protrudes from the partition wall portion 330. The third protrusion 303 overlaps with a part of the transistor 431 that constitutes the motor drive circuit 451 and the motor 220. Having the third protrusion 303 allows for further heat dissipation from the heat-generating component 43 and the motor 220.

[0093] Furthermore, the first protrusion 301 projects from the center of the partition wall 330 in the Y-axis direction toward the opening side of the substrate housing 213, which is the circuit board housing. The third protrusion 303 projects from the partition wall 330 between the first protrusion 301 and the wall portion 321, which has a surface along the axial direction. In other words, the third protrusion 303 is offset from the first protrusion 301 in the Y-axis direction and is located further outward from the substrate housing 213 than the first protrusion 301. As shown in Figures 8 and 9, the partition wall 330 is arc-shaped, and the outer side of the partition wall 330 in the Y-axis direction is lower in the height direction of the protrusion 300 as it is closer to the wall portion 320. The third protrusion 303, which is offset outward in the Y-axis direction from the first protrusion 301 and protrudes from the partition wall 330, protrudes from a lower position than the first protrusion 301 and has an end on the circuit board 40 side that extends to the same height as the first protrusion 301, and therefore has a larger volume than the first protrusion 301. This configuration allows for a larger volume for the third protrusion 303, enabling better heat dissipation from the heat-generating component 43 and the motor 220.

[0094] Furthermore, the third protrusion 303 is located between the first protrusion 301 and the wall portion 321 which has a surface aligned in the axial direction, and is connected to the second connecting portion 312. Because it is connected to the second connecting portion 312, the third protrusion 303 can dissipate the heat received from the heat-generating component 43 and the motor 220 to the wall portion 321 which has a surface aligned in the axial direction.

[0095] The third protrusion 303 is located between the first protrusion 301 and the wall portion 321 having a surface aligned in the axial direction, and is connected to the first protrusion 301 and the wall portion 321 having a surface aligned in the axial direction by the second connecting portion 312. The second connecting portion 312 between the third protrusion 303 and the wall portion 321 having a surface aligned in the axial direction protrudes from the partition wall portion 330 toward the circuit board 40. The height of the protrusion 300 of the second connecting portion is greater between the third protrusion 303 and the wall portion 321 having a surface aligned in the axial direction than between the first protrusion 301 and the third protrusion 303. Also, the distance of the second connecting portion 312 in the Y-axis direction is greater between the third protrusion 303 and the wall portion 321 having a surface aligned in the axial direction than between the first protrusion 301 and the third protrusion 303. The heat received by the first protrusion 301 and the third protrusion 303 is transmitted through the second connecting portion 312 and dissipated toward the wall portion 321 having a surface aligned in the axial direction. The second connecting portion 312, which is closer to the wall portion 321 having a surface aligned in the axial direction, i.e., the second connecting portion 312 between the third protrusion 303 and the wall portion 321 having a surface aligned in the axial direction, has a larger surface area than the second connecting portion 312 between the first protrusion 301 and the third protrusion 303, resulting in a larger surface area and superior heat dissipation. Furthermore, when the second connecting portion 312 is cross-sectionally viewed along the surface aligned in the axial direction, the cross-sectional area is larger between the third protrusion 303 and the wall portion 321 having a surface aligned in the axial direction. This larger cross-sectional area allows for greater heat dissipation toward the wall portion 321 having a surface aligned in the axial direction.

[0096] The connecting portion 310 has a third connecting portion 313 that extends from the first connecting portion 311 in a direction intersecting the axial direction and connects to a wall portion 321 having a surface aligned with the axial direction. The third connecting portion 313 receives heat from the first connecting portion 311 and can dissipate that heat to the wall portion 321 having a surface aligned with the axial direction, resulting in superior heat dissipation.

[0097] The connecting portion 310 has a fourth connecting portion 314 that extends axially from the second connecting portion 312 and connects to the wall portion 320. The fourth connecting portion 314 receives the heat received by the second connecting portion 312 and can also dissipate the heat to the wall portion 320, resulting in superior heat dissipation.

[0098] The connecting portion 310 further includes a fifth connecting portion 315 that connects the second protrusion 302 to the wall portion 321 having a surface aligned in the axial direction. The fifth connecting portion 315 allows the heat received by the second protrusion 302 to be dissipated to the wall portion 321 having a surface aligned in the axial direction.

[0099] The protrusion 300 may have a heat dissipation member 51 installed at its end on the circuit board 40 side, and may receive heat from the heat-generating component 43 via the heat dissipation member 51. Even if the heat-generating component 43 is relatively small relative to the end of the protrusion 300, using the heat dissipation member 51 allows the entire end of the protrusion 300 to receive heat, resulting in good heat dissipation from the heat-generating component 43. The heat dissipation member 51 may be provided for each protrusion 300, or the first to third protrusions 301 to 303, which are concentrated on the rear side, may be combined and installed as one large heat dissipation member 51. When the second surface 412 of the circuit board 40 is assembled facing the motor 220 side, heat can be transferred from the heat-generating component 43 to the heat dissipation member 51 through the through-holes 413 of the circuit board 40.

[0100] The first to fifth connecting sections 311 to 315 may have a stepped shape. By appropriately giving each connecting section 310 a stepped shape, it is possible to dissipate heat received from the protrusion 300 to the wall section 320 while avoiding interference with electronic components such as capacitors mounted on the circuit board 40.

[0101] The third housing recess 213a of the substrate housing 213 may be filled with grease, resin material, or a silicone-based material so as to connect from the protrusion 300 to the wall 320. By filling it with grease or resin material, heat from the heat-generating components 43 and motor 220 can be dissipated from the electric oil pump 200 to the outside not only through the connecting portion 310 but also through the filled grease or resin material.

[0102] If the first surface 411 of the circuit board 40 is assembled facing the protrusion 300, the stator 23 of the motor 220, the partition wall 330, the protrusion 300, and the heat-generating component 43 may be in contact in the order radially outward from the central axis J. The resin surface 435 of the heat-generating component 43, which faces the same direction as the first surface 411 of the circuit board 40, may be in contact with the protrusion 300 and dissipate heat to the protrusion 300.

[0103] The housing 210 is in contact with the pump cover 212b, which closes the second housing recess 212a from the front, and the bearing holder 226, which closes the first housing recess 211a from the rear. Because the pump cover 212b and the bearing holder 226 are in contact with the housing 210, the heat from the heat-generating components 43 and the motor 220 can be transferred from the housing 210 (protrusion 300, connecting portion 310) to the pump cover 212b and the bearing holder 226, and further heat can be dissipated to the outside from the outer surfaces of the pump cover 212b and the bearing holder 226. By making the pump cover 212b and the bearing holder 226 out of metal, heat conductivity is improved and heat dissipation is further improved. Also, by making the substrate cover 241, which is part of the housing 210 out of metal, heat dissipation can be further improved. Furthermore, the heat received by the protrusion 300 and the connecting portion 310 in this embodiment is not only dissipated to the outside from the outer surface of the wall portion 320. In other words, since the substrate housing 213 having the wall portion 320 is part of the housing 210, the heat received by the protrusion 300 and the connecting portion 310 is transferred from the wall portion 320 to the entire housing 210, allowing heat to be dissipated across the entire outer surface of the housing 210. Because heat can be dissipated across the entire outer surface of the housing 210, heat dissipation is excellent.

[0104] In this embodiment, the substrate surface is described as being aligned axially and the motor 220, protrusion 300, and heat-generating component 43 overlap radially, but the embodiment is not limited to this. The substrate surface may be arranged in a direction intersecting the axial direction, and the motor 220, protrusion 300, and heat-generating component 43 may overlap axially. In other words, when viewed from a cross section along the axial direction, the motor 220, protrusion 300, and heat-generating component 43 may overlap from one axial direction to the other, and when viewed from a cross section perpendicular to the axial direction, the motor 220, protrusion 300, and heat-generating component 43 may overlap axially. When the motor 220, protrusion 300, and heat-generating component 43 overlap axially, the partition wall 330 does not need to be arc-shaped and may have recesses or holes.

[0105] In this embodiment, the circuit board 40 is housed in the substrate housing 213, and the substrate housing 213 is provided with a protrusion 300 and a connecting portion 310. However, the substrate cover 241 of the housing 210 may be made into a box shape that opens toward the substrate housing 213 side (+Z side), and the substrate cover 241 may also be provided with a protrusion 300 and a connecting portion 310 on the inside of the substrate cover 241. Providing the substrate cover 241 with a protrusion 300 and a connecting portion 310 will allow for better heat dissipation.

[0106] Without departing from the spirit of the present invention, the configurations (components) described in the above embodiments, modifications, and provisos may be combined, and the configurations can be added, omitted, replaced, or otherwise modified. In this embodiment, the busbar unit 250 is configured to have a joint busbar holder 252, but it may also be configured without a joint busbar holder 252. In this embodiment, the second long side (long side) of the circuit board 40 is shown to be arranged in the direction along the axial direction, but the second short side (short side) of the circuit board 40 may also be arranged in the direction along the axial direction. By devising the circuit configuration, the circuit board 40 itself may be miniaturized, and the second long side (long side) of the circuit board 40 may intersect the axial direction to such an extent that the electric oil pump 200 does not adversely affect the mounting side, such as the transmission or body-related components of the nearby automobile. Furthermore, even when the second short side (short side) of the circuit board 40 is arranged along the axial direction, multiple circuit boards 40 may be provided, and the radial miniaturization may be achieved by devising the arrangement of the multiple circuit boards 40. For example, within the range where the second long side (long side) of one circuit board 40 is arranged along the axial direction, multiple circuit boards 40 may be arranged with their second short sides (short sides) aligned along the axial direction, or multiple circuit boards 40 may be arranged so that their board surfaces overlap with their second short sides (short sides) aligned along the axial direction. In this embodiment, the mounting plate portion 70 is shown to have an intake port 731, an outlet port 734, and a flow path 73, but it may also be configured without an intake port 731, an outlet port 734, and a flow path 73. For example, the circuit board 40 may be positioned on the motor 220 side so that its board surface does not overlap with the pump housing 212, and the intake port 731, outlet port 734, and flow path 73 may be configured around the pump housing 212. In this embodiment, the mounting plate portion 70 is shown to have mounting holes, but the mounting holes may be provided in other parts of the housing body 210. [Explanation of Symbols]

[0107] 210: Housing (Housing Body) 211: Motor Housing 213: Circuit board housing 241: Circuit board cover, 220: Motor 22: Rotor 23: Status 224a: Busbar 224d: Bus bar holder 210b: Through hole 30: Pump mechanism 40: Control board 43: Heat-generating components 411: 1st page 412:Second side 250: Busbar Unit 251a~251c: Joint busbar 252: Joint bus bar holder J: Central axis 301: First protrusion 302: Second protrusion 303: Third protrusion 304: Fourth protrusion 311: 1st connection part 312:Second connection part 313:Third connection part 314: 4th connection part 315: 5th connection part 320: Wall 330: Partition wall part 70: Mounting plate section 71: Mounting surface 711: First mounting surface 712: Second mounting surface 713: Third mounting surface 715: Fifth mounting surface (inlet mounting surface) 716: Sixth mounting surface (discharge port mounting surface)

Claims

1. A motor having a shaft that can rotate around a central axis, A pump mechanism connected to one side of the shaft in the axial direction, A circuit board located radially outward, perpendicular to the axial direction of the aforementioned shaft, A housing capable of accommodating the motor and the circuit board, Equipped with, The aforementioned circuit board is The shaft is opposed to the first surface, which is aligned in the axial direction and has an electronic component on one surface, and the second surface is a plate surface opposite to the first surface. The housing body is The housing comprises a motor housing portion for housing the motor, a circuit board housing portion for housing the circuit board, a pump housing portion for housing the pump mechanism, and a mounting plate portion located radially outward and perpendicular to the axial direction of the shaft. The aforementioned mounting plate portion is A mounting surface facing the aforementioned shaft and aligned in the axial direction, The pump mechanism has an inlet for drawing in fluid, The aforementioned pump mechanism has a discharge port from which fluid is discharged, It has, The motor and the pump mechanism are located on the inner corner side of the corner where the third surface, which includes the plate surface, and the fourth surface, which includes the mounting surface, intersect. The intake port is positioned offset in the axial direction from the discharge port when viewed from a direction perpendicular to the fourth surface on the mounting surface. An electric pump in which the intake port and the discharge port are offset from each other in a direction perpendicular to the axial direction when viewed from a direction perpendicular to the fourth surface on the mounting surface.

2. The aforementioned substrate housing portion is It has a first long side along the axial direction and a first short side that intersects the first long side and lies along the third surface, The electric pump according to claim 1.

3. The aforementioned circuit board is It has a second long side along the axial direction and a second short side that intersects the second long side and lies along the fourth face, The electric pump according to claim 1 or 2.

4. The aforementioned mounting plate portion is The shaft has thickness in a radial direction perpendicular to the axial direction, The motor and the pump mechanism and the mounting surface are, Displaced via the aforementioned thickness, The electric pump according to any one of claims 1 to 3.

5. The aforementioned substrate housing portion is It has a connector section for connecting to the outside, The aforementioned connector part is Extending axially from the substrate housing portion, An electric pump according to any one of claims 1 to 4.

6. The motor and the circuit board have a plurality of busbars that electrically connect them. The aforementioned busbar is It is connected to the end of the circuit board on the axial side, which is the motor side, The aforementioned connector part is Extending from the end of the substrate housing portion on the axial side, which is the pump mechanism side, The electric pump according to claim 5.

7. The mounting plate portion has at least two mounting holes, The aforementioned mounting hole has a first mounting hole and a second mounting hole, The first mounting hole is, Located on one axial side of the aforementioned pump housing portion, The electric pump according to any one of claims 1 to 6.

8. The mounting plate portion has at least two mounting holes, The aforementioned mounting hole has a first mounting hole and a second mounting hole, The second mounting hole is, Located on the other axial side from the motor housing portion, The electric pump according to any one of claims 1 to 6.

9. At least one of the mounting holes is Viewed from a direction perpendicular to the fourth surface, between the upper and lower ends of the housing body, The electric pump according to claim 7 or 8.

10. The aforementioned mounting plate portion is Having at least two mounting holes, The aforementioned mounting hole is It has a first mounting hole on one axial side and a second mounting hole on the other axial side, The aforementioned intake port and the aforementioned discharge port are Located between the first mounting hole and the second mounting hole, The electric pump according to any one of claims 1 to 6.

11. The mounting plate portion has a third mounting hole, The aforementioned intake port and the aforementioned discharge port are When viewed from the axial direction, the third mounting hole is located between the first mounting hole or the second mounting hole, The electric pump according to claim 10.

12. The aforementioned mounting surface is The intake port surface portion surrounding the aforementioned intake port, Having a discharge port surface portion surrounding the discharge port, The electric pump according to any one of claims 1 to 11.

13. The aforementioned mounting plate portion is Having a passage through which the fluid to be drawn in and discharged by the pump mechanism flows, The electric pump according to any one of claims 1 to 12.

14. The aforementioned flow path is It has an intake passage and a discharge passage that extend radially from the mounting surface and connect to the pump mechanism side, The aforementioned intake passage is Viewed from a direction perpendicular to the fourth surface, in the axial direction, between the discharge channel and the motor, The electric pump according to claim 13.

15. The aforementioned flow path is A discharge channel extending radially from the mounting surface and connected to the pump mechanism, A first intake passage extends radially from the mounting surface toward the shaft side, A second intake passage is connected to the first intake passage and passes through the mounting plate portion along the axial direction, It has a third suction passage that is connected to the second suction passage, extends radially, and is connected to the pump mechanism, The third intake passage is, Viewed from a direction perpendicular to the fourth surface, in the axial direction between the discharge passage and the first suction passage, The electric pump according to claim 13.

16. The aforementioned flow path is A suction passage connecting the aforementioned suction port to the pump mechanism side, A discharge channel connected from the discharge port to the pump mechanism side, A relief channel branching off from the discharge channel and returning the fluid to the intake channel side is provided. The electric pump according to claim 13.

17. At least a portion of the aforementioned intake passage is Viewed from a direction along the fourth surface, the relief flow path overlaps with the direction intersecting the axial direction, The electric pump according to claim 16.

18. The aforementioned mounting plate portion is Viewed from a direction perpendicular to the fourth surface, between the lower end of the substrate housing and the upper ends of the motor housing and pump housing, The electric pump according to any one of claims 1 to 17.

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