Electric pump

Abstract

To provide an electric pump that can be miniaturized. [Solution] The electric pump 100 includes a shaft 2 extending in the axial direction, a rotatable rotor 3 located radially outside the shaft 2, a stator 4 having a coil 41 and located radially outside the rotor 3 and surrounding the rotor 3, a pump unit 5 connected to one axial side of the rotor 3, a housing 7 housing the rotor 3 and the stator 4, a circuit board 9 located on the other axial side of the housing 7, and a busbar 151 having a coil connection portion connected to the coil 41 and connecting the circuit board 9 and the coil 41. The coil connection portion overlaps with the rotor 3 when viewed from the axial direction.

Description

Technical Field

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

Background Art

[0002] Conventionally, a seal-less electric pump that prevents fluid leakage by integrating a pump section and a motor section is known. Patent Document 1 discloses an electric pump having a cup-shaped partition member between a rotor constituting a motor section and a stator surrounding the rotor. In the electric pump of Patent Document 1, the partition member seals the inside of the rotor so that the fluid flowing into the rotor does not leak to the stator side.

[0003] Further, Patent Document 2 discloses an electric pump having a rotor rotatable about a central axis, a stator having a coil and facing the rotor with a gap in the radial direction, a plurality of terminals located on one axial side of the stator, and a substrate located on one axial side of the plurality of terminals. In the electric pump of Patent Document 2, the power of an external power source is supplied to the substrate through a connector section, and the power supplied to the substrate is supplied to the coil of the stator through a first terminal, a second terminal, and a third terminal from the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in Patent Documents 1 and 2, there is room for improvement in devising the configuration for supplying power from an external power source to the coil of the stator through the substrate and each terminal to reduce the size.

[0006] The objective of the present invention is to provide an electric pump that can be miniaturized. [Means for solving the problem]

[0007] One embodiment of the electric pump according to the present invention comprises an axially extending shaft, a rotatable rotor located radially outward from the shaft, a stator having a coil and located radially outward from the rotor and surrounding the rotor, a pump section connected to one axial side of the rotor, a housing housing the rotor and the stator, a circuit board disposed on the other axial side of the housing, and a busbar having a coil connection section connected to the coil and connecting the circuit board and the coil. The coil connection section overlaps with the rotor when viewed from the axial direction. [Effects of the Invention]

[0008] According to the present invention, electric pumps can be miniaturized. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a perspective view of an electric pump according to one embodiment. [Figure 2] Figure 2 is a plan view of an electric pump according to one embodiment. [Figure 3] Figure 3 is a cross-sectional view of AA in Figure 2. [Figure 4] Figure 4 is a perspective view of an electric pump according to one embodiment, with the inverter cover and heat sink removed. [Figure 5] Figure 5 is a perspective view of a partition wall member of an electric pump according to one embodiment. [Figure 6] Figure 6 is a bottom view of a partition wall member of an electric pump according to one embodiment. [Figure 7] Figure 7 is a perspective view of the shaft of an electric pump according to one embodiment. [Figure 8]FIG. 8 is a perspective view of an electric pump according to an embodiment with the inverter cover, heat dissipation material, circuit board, and insulating member removed. [Figure 9] FIG. 9 is a cross-sectional view of the pump section of an electric pump according to an embodiment. [Figure 10] FIG. 10 is a cross-sectional perspective view of the partition member and rotor cover of an electric pump according to an embodiment. [Figure 11] FIG. 11 is a cross-sectional view taken along the line B - B of FIG. 3. [Figure 12] FIG. 12 is a cross-sectional view taken along the line C - C of FIG. 3. [Figure 13] FIG. 13 is a cross-sectional view of the inverter cover and its surroundings of an electric pump according to an embodiment. [Figure 14] FIG. 14 is a perspective view of an electric pump according to an embodiment with the inverter cover removed. [Figure 15] FIG. 15 is an enlarged cross-sectional view of the inverter cover and its surroundings of an electric pump according to an embodiment. [Figure 16] FIG. 16 is a perspective view of an electric pump according to an embodiment with the inverter cover, heat dissipation material, circuit board, insulating member, housing, and reinforcing member removed. [Figure 17] FIG. 17 is an enlarged perspective view of a part of the bus bar assembly of an electric pump according to an embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an electric pump according to an embodiment of the present invention will be described with reference to the drawings. Note that the scope of the present invention is not limited to the following embodiments and can be changed within the scope of the technical idea of the present invention. Also, in the following drawings, in order to make each configuration easier to understand, the scale and number, etc. of each structure may be different from those in the actual structure. In the description of the embodiment, expressions such as up, down, left, and right may be used, but such expressions are for facilitating the understanding of the embodiment and do not limit the present invention.

[0011] <Configuration of Electric Pump> The configuration of the electric pump 100 according to an embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 14.

[0012] The electric pump 100 includes a shaft 2, a rotor 3, a stator 4, a pump section 5, a partition member 6, a housing 7, an auxiliary member 8, a circuit board 9, an insulating member 10, a bearing member 12, an inverter cover 13, a heat dissipation material 14, a bus bar assembly 15, a rotor cover 16, and a fixing member 17. Note that in FIG. 13, the description of the heat dissipation material 14 is omitted.

[0013] The shaft 2 extends in the axial direction (the vertical direction in FIG. 3). The shaft 2 does not rotate. The shaft 2 has a fastening hole 21 on the lower end surface in the axial direction and an opposing portion 22 on the upper end surface in the axial direction. Further, the shaft 2 has a housing fitting portion 23 on the side surface (circumferential surface) on the other side in the axial direction and below the opposing portion 22.

[0014] The fastening hole 21 is a hole formed inside the chamber fitting portion 24 and extends from one end in the axial direction of the shaft 2 (the lower end in FIG. 3) toward the other side in the axial direction (upward in FIG. 3).

[0015] The opposing portion 22 is provided at the end on the other side in the axial direction of the shaft 2 and is in contact with the insulating member 10 in opposition by being exposed to the other side in the axial direction of the upper wall portion 71 (FIG. 8) of the housing 7. The opposing portion 22 has a larger diameter than the other portions of the shaft 2 other than the opposing portion 22. The opposing portion 22 may be referred to as a diameter-expanded portion. The opposing portion 22 faces the other side in the axial direction and is provided along the first surface on the one side in the axial direction of the circuit board 9.

[0016] The housing fitting portion 23 fits into the shaft fitting portion 712 of the upper wall portion 71 on the other side in the axial direction of the shaft 2.

[0017] The chamber fitting portion 24 is fixed and connected to the shaft fitting portion 513 (Figure 9) of the pump portion 5 at one axial end of the shaft 2. The chamber fitting portion 24 is a shaft heat dissipation portion located in the pump portion 5 on one axial side of the housing fitting portion 23.

[0018] The rotor 3 is a cylindrical member located radially outward from the shaft 2. The rotor 3 includes a rotor core, a magnet, and a rotor cover 16. The rotor 3 rotates due to the electromagnetic field generated by the stator 4. The rotor 3 has three through holes 31 that extend in the axial direction. The three through holes 31 are spaced 120 degrees apart around the bearing member 12.

[0019] The stator 4 is located radially outward from the rotor 3 and surrounds the rotor 3. The stator 4 has a coil 41 connected to the busbar 151 of the busbar assembly 15. The stator 4 has a mating portion 32 on the other axial side that mates with the busbar assembly 15. The busbar assembly 15 has a smaller diameter than the stator 4. Because the busbar assembly 15 has a smaller diameter than the stator 4, it is possible to suppress radial enlargement, and at the same time, the assembly workability of the stator 4 and housing 7 is excellent. The coil 41 of the stator 4 is powered from a power source (not shown) via a connector 91a and busbar 151 mounted on the circuit board 9, and an electromagnetic field is generated when current flows through the coil 41.

[0020] The pump unit 5 is located on one axial side of the housing 7. The pump unit 5 includes a chamber 51 and an impeller 52.

[0021] The chamber 51 is fixed to one axial side of the housing 7. The chamber 51 has an intake port 511, an outlet port 512, and a shaft fitting portion 513.

[0022] The intake port 511 draws fluid in the direction of F1 into the chamber 51. The fluid flowing into the chamber 51 is water or oil, etc.

[0023] The discharge port 512 directs the fluid, which is drawn in from the intake port 511 and moves in the F2 direction due to the rotation of the impeller 52, towards the F3 direction, thereby discharging it to the outside of the chamber 51.

[0024] The shaft fitting portion 513 extends from one axial side to the other axial side of the chamber 51. The shaft fitting portion 513 passes inside the through hole 522a of the lower disc portion 522 and the through hole 521a of the upper disc portion 521 of the impeller 52. The shaft fitting portion 513 fits with one axial side of the shaft 2 and is fixed to the shaft 2 by the fixing member 17.

[0025] The impeller 52 is located inside the chamber 51. The impeller 52 is connected to the rotor 3 and is rotatable together with the rotor 3. The impeller 52 has an upper disc portion 521, a lower disc portion 522, and a blade portion 523.

[0026] The upper disc portion 521 is disc-shaped and faces the partition member 6 with a gap in the axial direction. The upper disc portion 521 has a through hole 521a and a cylindrical portion 521b.

[0027] The through-hole 521a is a circular hole centered on the central axis P, which is the rotation center of the rotor 3. The through-hole 521a faces the through-hole 31 of the rotor 3 in the axial direction.

[0028] The cylindrical portion 521b extends axially toward the other side around the through hole 521a. The cylindrical portion 521b fits with the axial end of the rotor 3, allowing the impeller 52 to rotate together with the rotor 3.

[0029] The lower disc portion 522 is disc-shaped and has a circular through hole 522a centered on the central axis P. The lower disc portion 522 faces the upper disc portion 521 with a gap between them in the axial direction. The through hole 522a faces the through hole 521a in the axial direction and communicates with the intake port 511.

[0030] The blade portion 523 is connected to the upper disc portion 521 and the lower disc portion 522.

[0031] The impeller 52 rotates the fluid drawn into the chamber 51 from the intake port 511, thereby applying centrifugal force to the fluid, and the centrifugal force applied to the fluid causes the fluid to be discharged from the discharge port 512.

[0032] The partition member 6 is provided to cover the rotor 3 from the other axial side. The partition member 6 is a hat-shaped member. The partition member 6 is made of a material such as a resin with high thermal conductivity. The partition member 6 is located between the rotor 3 and the pump section 5 and the stator 4. The partition member 6 has a first partition section 61, a second partition section 62, a third partition section 63, a fourth partition section 64, a fifth partition section 65, and ribs 66.

[0033] The first partition wall 61 has an insertion hole 613 through which the shaft 2 passes. The first partition wall 61 is plate-shaped. The first partition wall 61 is located on the other axial side of the rotor 3. The first partition wall 61 extends radially outward from the shaft 2. The first partition wall 61 faces the first wall 161 of the rotor cover 16 with an axial gap between them, and together with the first wall 161, forms a flow path R2 (second flow path) (Figure 10). Fluid drawn in from the suction port 511 of the pump unit 5 that does not go toward the discharge port 512 flows through the flow path R2. The first partition wall 61 has a first surface 611 (Figure 3) and a second surface 612 (Figure 3) opposite the first surface 611. Details of the fluid flow path will be explained later in the description of the operation of the electric pump 100.

[0034] The first surface portion 611 is in contact with the auxiliary member 8.

[0035] The second surface 612 has radial ribs 612a (Figure 6) that extend radially outward from the shaft 2 and faces the flow path R2. As shown in Figure 6, the second surface 612 has radial ribs 612a that extend radially outward from the shaft 2. The second surface 612 has multiple ribs 612a. The multiple ribs 612a are arranged at equal intervals in the circumferential direction. The spacing between the multiple ribs 612a in the circumferential direction becomes narrower from the radially outward to the radially inward direction. The ribs 612a face the flow path R2.

[0036] The second partition wall 62 is cylindrical and extends axially from the radial outer peripheral edge of the first partition wall 61 between the rotor 3 and the stator 4. The second partition wall 62 faces the stator 4 with a gap between them in the radial direction. The second partition wall 62 faces the second wall 162 of the rotor cover 16 (described later) with a gap between them in the radial direction and, together with the second wall 162, forms a flow path R1, thereby facing the flow path R1 (first flow path). Fluid drawn in from the inlet 511 of the pump unit 5 that does not head toward the discharge port 512 flows through the flow path R1.

[0037] The third bulkhead section 63 extends radially outward from one axial end of the second bulkhead section 62 between the stator 4 and the pump section 5.

[0038] The fourth partition wall 64 extends from the radial outer peripheral edge of the third partition wall 63 toward the other axial direction.

[0039] The fifth bulkhead section 65 extends radially outward from the axial end of the fourth bulkhead section 64 between the housing 7 and the pump section 5.

[0040] Multiple ribs 66 are provided at intervals along the circumferential direction of the second partition wall 62 and are connected to the second partition wall 62 and the third partition wall 63.

[0041] The housing 7 houses the rotor 3 and the stator 4. The housing 7 has an upper wall portion 71 located on one axial side of the partition member 6.

[0042] The upper wall portion 71 is in contact with the insulating member 10. The upper wall portion 71 has a recess 711 that is recessed toward one side in the axial direction. The opposing portion 22 of the shaft 2 is exposed in the recess 711. The upper wall portion 71 has a shaft fitting portion 712 that fits into the housing fitting portion 23 of the shaft 2 on the radially outer side of the shaft 2, and serves as a shaft fixing portion.

[0043] The auxiliary member 8 is provided between the other axial side (first partition portion 61) of the partition member 6 and the upper wall portion 71 of the housing 7. The auxiliary member 8 supports (assists) the first partition portion 61 of the partition member 6 so that it does not bend due to the pressure of the fluid flowing through the flow path R2. The auxiliary member 8 has a large diameter portion 81 and a small diameter portion 82. The small diameter portion 82 has a smaller diameter than the large diameter portion 81 when viewed in the axial direction.

[0044] The large-diameter portion 81 is provided at one end of the auxiliary member 8 on the axial side and is fitted into the partition member 6.

[0045] The small-diameter portion 82 extends from the large-diameter portion 81 in the opposite direction in the axial direction. The small-diameter portion 82 is provided to reduce the volume and thus the weight of the auxiliary member 8.

[0046] The circuit board 9 is provided on the other axial side of the upper wall portion 71 of the housing 7 via an insulating member 10. The circuit board 9 covers substantially the entire other axial side (second surface) of the upper wall portion 71. Multiple different electronic components 91 are mounted on the other axial side of the circuit board 9. One axial side (first surface) of the circuit board 9 is in contact with the insulating member 10.

[0047] Multiple electronic components 91 mounted on the circuit board 9 include a connector 91a. The electronic components 91 also include ICs (integrated circuits) that constitute the drive circuit and control circuit. A signal cable 91b for receiving a predetermined signal, which is connected to a signal supply source (not shown), and a power cable 91c for receiving power, which is connected to a power supply (not shown), are connected to the connector 91a.

[0048] Each of the signal cable 91b and the power cable 91c is fixed by a fixing member 92 to the other axial side of the protrusion 133 of the inverter cover 13 and pulled out.

[0049] The insulating member 10 is a sheet-like member provided between one axial side of the circuit board 9 and the upper wall portion 71 of the housing 7. The insulating member 10 is provided to insulate the circuit board 9 from the upper wall portion 71. The insulating member 10 is also a heat conductive member formed of a thermally conductive material such as silicon. The insulating member 10 is in overall radial contact with the circuit board 9 and the upper wall portion 71.

[0050] The bearing member 12 is provided between the shaft 2 and the rotor 3. The shaft 2 is inserted into the bearing member 12.

[0051] The inverter cover 13 covers the other axial side of the circuit board 9 and the heat dissipation material 14. The inverter cover 13 has a base portion 131, a plurality of heat dissipation portions 132, a protruding portion 133, and a plurality of heat dissipation fins 134.

[0052] The base 131 is positioned on the other axial side of the circuit board 9 and is in contact with the heat dissipation material 14. The base 131 is circular when viewed from the axial direction.

[0053] Multiple heat dissipation sections 132 protrude from the base 131 toward the other axial direction. The multiple heat dissipation sections 132 cover the electronic components 91 mounted on the circuit board 9 and also have heat dissipation fins 134 and recesses 132a.

[0054] The multiple heat dissipation fins 134 are plate-shaped and protrude from the base 131 in the opposite direction in the axial direction. The multiple heat dissipation fins 134 are arranged parallel to each other with spacing between them.

[0055] The recess 132a is recessed on the other side in the axial direction.

[0056] The protrusion 133 protrudes axially to the other side from the multiple heat dissipation parts 132. The protrusion 133 is provided on the radial outer edge of the cover 13. The protrusion 133 has a crescent shape when viewed from the other side in the axial direction. The protrusion 133 covers the connector 91a, which is one of the electronic components 91 mounted on the circuit board 9. The protrusion 133 protrudes axially to the other side from the multiple heat dissipation parts 132 because it is necessary to provide a certain distance between the connector 91a and the fixing member 92 so as not to put a load on the connection between the connector 91a mounted on the circuit board 9 and the signal cable 91b and the power cable 91c.

[0057] The heat dissipation material 14 covers the other axial side of the circuit board 9 where the electronic components 91 are mounted.

[0058] The busbar assembly 15 is located between the circuit board 9 and the stator 4. The busbar assembly 15 is housed in the housing 7 and is fitted into the fitting portion 42 of the stator 4. When viewed from the other axial side, the busbar assembly 15 has a smaller diameter than the stator 4. The busbar assembly 15 includes busbars 151 and busbar support members 152.

[0059] The busbar 151 is formed of a conductive material such as metal. At least a portion of the busbar 151 overlaps with the stator 4 when viewed from the other axial side. At least a portion of the busbar 151 overlaps with the shaft fitting portion 712 when viewed from the radial direction. At least a portion of the busbar 151 overlaps with the large diameter portion 81 of the auxiliary member 8 when viewed from the other axial side. At least a portion of the busbar 151 overlaps with the partition member 6 when viewed from the other axial side. The busbar 151 has a coil connection portion 151a, a circuit board connection portion 151b, and a holding portion 151c.

[0060] The coil connection portion 151a extends radially inward from the holding portion 151c and is provided in pairs. The pair of coil connection portions 151a are each connected to the coils 41 of adjacent stator 4 in the circumferential direction with respect to the central axis P. The coil connection portion 151a is U-shaped when viewed radially. The coil connection portion 151a overlaps with the rotor 3 when viewed axially. The coil connection portion 151a overlaps with the stator 4 when viewed from the other axial side. The coil connection portion 151a overlaps with the shaft fitting portion 712 when viewed radially. The coil connection portion 151a overlaps with the large diameter portion 81 of the auxiliary member 8 when viewed from the other axial side. The coil connection portion 151a overlaps with the partition member 6 when viewed from the other axial side.

[0061] The circuit board connection portion 151b is provided in pairs and is pin-shaped, protruding from the holding portion 151c in the other axial direction.

[0062] The retaining portion 151c is provided between the coil connection portion 151a and the circuit board connection portion 151b, and is held and fixed by the busbar support member 152. The other axial side of the retaining portion 151c protrudes in the other axial direction from the substrate-side projection 152a of the busbar support member 152, which will be described later. The other axial side of the circuit board connection portion 151b and the other axial side of the retaining portion 151c protrude in the other axial direction from the substrate-side projection 152a and are soldered to the other axial side surface of the circuit board 9 via a through-hole (not shown) of the circuit board 9, thereby connecting to the circuit board 9, and are also connected to the electronic components 91 mounted on the other axial side surface of the circuit board 9.

[0063] The busbar support member 152 is made of an insulating material. The busbar support member 152 holds the busbar 151. The busbar support member 152 has a coil lead hole 152b that penetrates radially outward along the axial direction. The coil 41 passes through the coil lead hole 152b. The busbar support member 152 has a substrate-side projection 152a that protrudes radially to the other side. The substrate-side projection 152a holds the holding portion 151c of the busbar 151.

[0064] The rotor cover 16 completely covers the rotor core. The rotor cover 16 has at least a first wall portion 161 and a plurality of second wall portions 162.

[0065] The first wall portion 161 faces the second surface portion 612 of the partition wall member 6 with an axial gap between them. The first wall portion 161 has a surface facing the other side in the axial direction.

[0066] The second wall portion 162 is located between the second partition portion 62 of the partition member 6 and the rotor core. The second wall portion 162 is the outer circumferential surface (outer diameter surface) of the rotor 3. The second wall portion 162 has a surface facing radially outward.

[0067] The fixing member 17 fixes the pump unit 5 to one axial side of the shaft 2. The fixing member 17 has a fastening portion 171 that is fastened to the fastening hole 21 of the shaft 2, and a top portion 172 that is larger in diameter than the fastening portion 171. The top portion 172 faces the flow path of the pump unit 5. The top portion 172 is in contact with the fluid that is drawn in from the suction port 511 and heads toward the discharge port 512.

[0068] <Operation of the electric pump> The operation of the electric pump 100 according to an embodiment of the present invention will be described in detail below with reference to Figures 1 to 14.

[0069] When power is supplied to the stator 4 from a power source (not shown) via the power cable 91c, the connector 91a mounted on the circuit board 9, and the busbar 151, the stator 4 forms an electromagnetic field. This electromagnetic field causes the rotor 3 to rotate. As the rotor 3 rotates, the impeller 52, which is mated with the rotor 3, also rotates.

[0070] Fluid such as water is drawn into the chamber 51 of the pump unit 5 from the suction port 511 in the direction of F1, and flows toward the discharge port 512 in the direction of F2 due to the centrifugal force caused by the rotation of the impeller 52. Subsequently, the fluid flows toward the discharge port 512 in the direction of F3 and is discharged from the discharge port 512.

[0071] In this case, some of the fluid flowing in the F2 direction does not flow in the F3 direction. The fluid that does not flow in the F3 direction flows in the F4 direction in the gap between the upper disc portion 521 and the lower disc portion 522 of the impeller 52, and flows into the interior of the partition member 6 through the gap between the upper disc portion 521 and the third partition portion 63 of the partition member 6. In this embodiment, since the partition member 6 is provided with ribs 66, the third partition portion 63 can be supported by the second partition portion 62 and the fourth partition portion 64, and a decrease in the rigidity of the partition member 6 can be suppressed (or prevented). Since a decrease in the rigidity of the partition member 6 is suppressed (or prevented), deformation and damage to the partition member 6 due to pressure from the fluid flowing in the F4 direction can be avoided.

[0072] The fluid that flows into the interior of the partition member 6 flows in the direction F5 axially toward the other side through the flow path R1 in the gap between the second partition portion 62 of the partition member 6 and the multiple second wall portions 162 of the rotor cover 16. Subsequently, the fluid flows radially in the direction F6 through the flow path R2 in the gap between the first partition portion 61 of the partition member 6 and the first wall portion 161 of the rotor cover 16. At this time, the second surface portion 612 of the first partition portion 181 comes into contact with the fluid flowing in the flow path R2 in the direction F6 between the first partition portion 61 and the first wall portion 161. Furthermore, since the first partition portion 61 is supported by the auxiliary member 8 to prevent it from bending, the third partition portion 63 can be supported by the second partition portion 62 and the fourth partition portion 64, thereby suppressing (or preventing) a decrease in the rigidity of the partition member 6. Since the reduction in rigidity of the partition wall member 6 can be suppressed (or prevented), deformation and damage to the partition wall member 6 due to pressure from the fluid flowing in the F6 direction can be avoided.

[0073] The fluid that flows in the direction of F6 through the flow path R2 in the gap between the first partition wall 61 and the first wall 161 reaches the rotor 3 and then flows into the through hole 31 of the rotor 3. The fluid that flows into the through hole 31 flows in the direction of F7 through the flow path R3 of the through hole 31. Subsequently, this fluid flows through the through hole 521a of the upper disc portion 521 of the impeller 52 and merges with the fluid that flows in the gap between the upper disc portion 521 and the lower disc portion 522 and flows in the direction of F2.

[0074] Thus, according to this embodiment, by configuring the coil connection portion 151a to overlap with the rotor 3 when viewed from the axial direction, the radial size of the electric pump 100 can be reduced by the amount by which the coil connection portion 151a and the rotor 3 overlap, thereby making the entire electric pump 100 more compact.

[0075] Furthermore, according to this embodiment, by configuring the coil connection portion 151a to overlap with the shaft fitting portion 712 when viewed from the radial direction, the axial size of the electric pump 100 can be reduced by the amount by which the coil connection portion 151a and the shaft fitting portion 712 overlap, thereby making the entire electric pump 100 more compact.

[0076] Furthermore, according to this embodiment, by configuring the coil connection portion 151a to overlap with the auxiliary member 8 when viewed from the axial direction, the radial size of the electric pump 100 can be reduced by the amount by which the coil connection portion 151a and the auxiliary member 8 overlap, thereby making the entire electric pump 100 more compact.

[0077] Furthermore, according to this embodiment, by configuring the coil connection portion 151a to overlap with the large-diameter portion 81 when viewed from the axial direction, the radial size of the electric pump 100 can be reduced by the amount by which the coil connection portion 151a and the large-diameter portion 81 overlap, thereby making the entire electric pump 100 more compact.

[0078] Furthermore, according to this embodiment, by configuring the coil connection portion 151a to overlap with the partition member 6 when viewed from the axial direction, the radial size of the electric pump 100 can be reduced by the amount by which the coil connection portion 151a and the partition member 6 overlap, thereby making the entire electric pump 100 more compact.

[0079] Furthermore, according to this embodiment, since the bus bar 151 protrudes from the substrate-side projection 152a in the other axial direction and connects to the circuit board 9, the bus bar 151 can be supported by the substrate-side projection 152a, thus enabling a stable connection between the bus bar 151 and the circuit board 9.

[0080] The embodiments described above should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the embodiments described above, and all modifications within the meaning and scope of the claims are intended to be included.

[0081] Specifically, in the above embodiment, the coil connection portion 151a and the shaft fitting portion 712 are arranged to overlap when viewed from the radial direction, but the coil connection portion 151a and the shaft fitting portion 712 may be arranged so that they do not overlap when viewed from the radial direction.

[0082] Furthermore, in the above embodiment, the coil connection portion 151a and the auxiliary member 8 are arranged to overlap when viewed from the other axial side, but the coil connection portion 151a and the auxiliary member 8 may be arranged not to overlap when viewed from the other axial side.

[0083] Furthermore, although the auxiliary member 8 is provided with a small-diameter portion 82 in the above embodiment, the coil connection portion 151a and the auxiliary member 8 may be arranged to overlap when viewed from the other axial side without providing the small-diameter portion 82 to the auxiliary member 8.

[0084] Furthermore, in the above embodiment, the coil connection portion 151a and the partition member 6 are arranged to overlap when viewed from the other axial side, but the coil connection portion 151a and the partition member 6 may be arranged not to overlap when viewed from the other axial side. [Explanation of Symbols]

[0085] 2 shafts 3 rotors 4 stata 5 Pump section 6. Partition Member 7 Housing 8. Auxiliary members 9 Circuit board 10 Insulating material 13 Inverter cover 14 Heat dissipation material 15 Busbar Assembly 16 Rotor Cover 17 Fixing member 22 Self-centered part 23 Housing fitting section 41 coils 52 Impeller 61 1st bulkhead part 62 2nd bulkhead part 71 Upper wall 81 Large diameter section 82 Small diameter section 91 Electronic Components 91a connector 100 Electric Pumps 132 Heat radiation part 133 Protrusion 151 Bus Bar 151a Coil connection section 511 Inlet 512 Discharge port

Claims

1. It is an electric pump, A shaft extending in the axial direction, A rotatable rotor located radially outward from the shaft, A stator having a coil, located radially outward from the rotor and surrounding the rotor, A pump section connected to one axial side of the rotor, A housing that accommodates the rotor and the stator, A circuit board is positioned on the other axial side of the housing, A busbar having a coil connection portion that connects to the coil, and connecting the circuit board and the coil, It has, The coil connection portion is, When viewed from the axial direction, it overlaps with the rotor, Electric pump.

2. The aforementioned housing is The shaft has a shaft fixing portion that fixes the shaft on the radially outer side of the shaft, The coil connection portion is, When viewed from the radial direction, it overlaps with the shaft fixing portion, The electric pump according to claim 1.

3. The aforementioned electric pump is A partition wall member is provided so as to cover the rotor from the other axial side, and is located between the rotor and the pump section and the stator. An auxiliary member that supports the partition wall member, It has, The aforementioned housing is The partition wall member has an upper wall portion located on the other axial side, The aforementioned auxiliary member is Provided between the partition wall member and the upper wall portion, The coil connection portion is, When viewed from the axial direction, it overlaps with the auxiliary member, The electric pump according to claim 1 or claim 2.

4. The aforementioned auxiliary member is It has a large diameter portion on one axial side and a small diameter portion provided on the other axial side of the large diameter portion and having a smaller diameter than the large diameter portion. The coil connection portion is, When viewed from the axial direction, it overlaps with the large diameter portion, The electric pump according to claim 3.

5. The aforementioned electric pump is The rotor is provided so as to cover the rotor from the other axial side, and has a partition member located between the rotor and the pump section and the stator, The coil connection portion is, When viewed from the axial direction, it overlaps with the partition wall member, The electric pump according to claim 1 or claim 2.

6. The aforementioned electric pump is The circuit board and the stator have a busbar assembly provided between them. The aforementioned busbar assembly is The aforementioned busbar, It has a busbar support member that supports the busbar, The busbar support member is The outer peripheral edge in the radial direction has a substrate-side protrusion that projects in the other axial direction, The aforementioned busbar is The protrusion on the substrate side extends axially in the other direction and connects to the circuit board. The electric pump according to claim 1 or claim 2.

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