Electric pump

Abstract

The present invention provides an electric pump that can suppress radial bending of the shaft even when subjected to the centrifugal force of the rotor. [Solution] The electric pump comprises a shaft 12 extending in the axial direction, a rotatable rotor located radially outward from the shaft 12, a stator located radially outward from the rotor and surrounding the rotor, a pump section 20 located on one axial side of the shaft 12, and a housing 21 having a pump housing section 20h that houses the pump section 20. Furthermore, the pump housing section 20h has a support section 23 that supports the axial end of the shaft 12.

Description

Technical Field

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

Background Art

[0002] Conventionally, a pump device is known in which a pump unit is connected to a motor unit and a shaft of the motor unit has a cantilever support structure. As shown in, for example, Patent Documents 1 and 2 below, the shaft is cantilever supported in a rotatable state via a sliding bearing on a separation plate that is held in contact with the end face of the stator.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the cantilever support structure of the shaft, there is a risk that the shaft will bend in the radial direction due to the influence of the centrifugal force when the rotor rotates. If the shaft bends in the radial direction, the rotor may contact the stator, generating noise or reducing the pump efficiency. Therefore, an object of the present invention is to provide an electric pump that can suppress the shaft from bending in the radial direction even when receiving the centrifugal force of the rotor.

Means for Solving the Problems

[0005] 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 located radially outward from the rotor and surrounding the rotor, a pump section located on one axial side of the shaft, and a housing having a pump housing section that accommodates the pump section, wherein the pump housing section has a support section that supports the axial end of the shaft on one side. [Effects of the Invention]

[0006] According to one aspect of the present invention, the radial bending of the shaft can be suppressed even when subjected to the centrifugal force of the rotor. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a perspective view of an electric pump according to one embodiment, viewed from the other side in the axial direction. [Figure 2] Figure 2 is a cross-sectional view of an electric pump according to one embodiment, cut along its central axis. [Figure 3] Figure 3 is a perspective view showing the electric pump of one embodiment shown in Figure 1 with the control unit removed. [Figure 4] Figure 4 is a perspective view of the first housing of one embodiment, viewed from one axial side. [Figure 5] Figure 5 is an exploded perspective view of a partition wall member of one embodiment, viewed from the other side in the axial direction. [Figure 6] Figure 6 is a perspective view of a partition wall member of one embodiment, viewed from one axial direction. [Figure 7] Figure 7 is a magnified view of section A in Figure 2. [Figure 8] Figure 8 is a magnified view of section B in Figure 2. [Figure 9] Figure 9 is a perspective view of a partition wall member of one embodiment, viewed from the other side in the axial direction. [Figure 10] Figure 10 is a perspective view of the second housing of one embodiment, which houses the pump unit, viewed from the other axial side. [Figure 11]Figure 11 is a perspective view of the second housing of one embodiment, viewed from one axial side. [Figure 12] Figure 12 is an exploded perspective view of the pump section and the second housing of one embodiment, viewed from the other axial side. [Figure 13] Figure 13 is a magnified view of section C in Figure 2. [Figure 14] Figure 14 is a magnified view of part A of Figure 13. [Modes for carrying out the invention]

[0008] Hereinafter, embodiments of the electric pump 100 of this disclosure will be described with reference to the attached drawings. Each figure virtually shows the central axis J of the electric pump 100 of this embodiment. In the following description, the axial direction of the central axis J will be simply referred to as the "axial direction," the radial direction centered on the central axis J will be simply referred to as the "radial direction," and the circumferential direction centered on the central axis J will be simply referred to as the "circumferential direction." The Z-axis shown in each figure indicates the direction in which the central axis J extends.

[0009] Furthermore, in the description of this embodiment, in order to make it easier to understand the configuration of each part, the direction in which the Z-axis arrow points (upper side in the figure) will be referred to as the "other axial side." Note that the "other axial side" may sometimes be simply referred to as the "upper side." Also, in the description of this embodiment, the direction opposite to the direction in which the Z-axis arrow points will be referred to as the "one axial side." Note that the "one axial side" may sometimes be simply referred to as the "lower side." In the description of this embodiment, the upper side and lower side are convenient terms used to explain the relative positional relationship of each part. The actual arrangement may be different from the arrangement indicated by these terms.

[0010] The electric pump 100 in this embodiment, shown in Figures 1 and 2, is, for example, a water pump for cooling that sends water as a fluid (refrigerant), or an oil pump for cooling that sends oil as a fluid (refrigerant). Figure 1 is a perspective view of the electric pump 100 from diagonally above. Figure 2 is a cross-sectional view of the electric pump 100 cut along the central axis J.

[0011] The electric pump 100 of this embodiment has a motor unit 10, a pump unit 20 located on one axial side (lower side) of the motor unit 10, a control unit 30 located on the other axial side (upper side) of the motor unit 10, and a housing H. The motor unit 10, pump unit 20, and control unit 30 are housed within a metal housing H. The housing H has a first housing 11 that houses the motor unit 10, a second housing 21 that houses the pump unit x0, and a third housing 31 that houses the control unit 30. Hereinafter, the configurations of the motor unit 10, pump unit 20, and control unit 30 will be described in detail.

[0012] (Motor unit 10) As shown in Fig. 2, the motor unit 10 has a shaft 12 located on the central axis J and extending in the direction of the central axis J (axial direction), a rotor 13 located radially outside the shaft 12, and a stator 15 surrounding the rotor 13. The motor unit 10 is housed in a motor housing portion 11h (Fig. 4) within the first housing 11. Fig. 4 is a perspective view of the first housing 11 as seen from below.

[0013] As shown in Fig. 3, the first housing 11 has a cylindrical outer shell 11a and an upper portion 11b provided on the upper side of the outer shell 11a. The upper portion 11b is a disc-shaped member. Fig. 3 is a perspective view showing the state where the control unit 30 is removed from the electric pump 100 shown in Fig. 1. As shown in Fig. 4, the first housing 11 has a first opening 11k that opens toward the pump unit 20 side. A flange 11m extending radially outward is formed at the edge of the first opening 11k. The flange 11m is formed along the circumferential direction of the edge of the first opening 11k. A first surface 11n facing the pump unit 20 side is formed on the flange 11m. The first surface 11n is a flat surface without steps, excluding the groove for accommodating the O-ring. Also, a plurality of screw holes 11p are formed in the flange 11m. The screw holes 11p are formed at predetermined intervals along the circumferential direction of the flange 11m.

[0014] As shown in Fig. 3, a shaft fixing portion 11c is formed on the upper portion 11b of the first housing 11. The end portion (upper end portion) on the other axial side of the shaft 12 is fixed to the shaft fixing portion 11c. The shaft fixing portion 11c is composed of a shaft fixing hole h1 formed at the center of the upper portion 11b. As shown in Fig. 7, the upper end portion of the shaft fixing hole h1 has a larger diameter compared to other portions of the shaft fixing hole h1, and an annular first step portion s1 is formed by the enlarged diameter portion. Fig. 7 is a partially enlarged view showing a portion A of Fig. 2.

[0015] As shown in Fig. 7, a second step portion 12a that spreads in a flange shape is formed at the end portion (upper end portion) on the other axial side of the shaft 12. The second step portion 12a of the shaft 12 has a larger diameter compared to other portions of the shaft 12. The shaft 12 is inserted into and fixed to the shaft fixing hole h1. When the shaft 12 is inserted into and fixed to the shaft fixing hole h1, the second step portion 12a of the shaft 12 faces the first step portion s1 in the axial direction. More specifically, the second step portion 12a is in contact with the first step portion s1 in the axial direction. Since the second step portion 12a of the shaft 12 is in contact with the first step portion s1 in the axial direction, it is possible to prevent the shaft 12 from moving (shifting) to the other axial side (lower side) even when a pulling force acts on the shaft 12 in the axial direction on one side (lower side). The fixing of the shaft 12 to the shaft fixing portion 11c is performed by press-fitting.

[0016] As shown in Fig. 2, a cylindrical rotor 13 is disposed on the outer side in the radial direction of the shaft 12 so as to surround the shaft 12. The rotor 13 is rotatable about the shaft 12. The rotor 13 includes a rotor core 13a, a magnet 13b, a rotor support plate 13c, a rotor support shaft 13d, and a rotor cover 13f. The rotor core 13a is formed by laminating dozens of laminated steel plates (electromagnetic steel plates).

[0017] The rotor support plates 13c are located above and below the rotor core 13a. The rotor support plates 13c sandwich the magnet 13b and the rotor core 13a from above and below. The rotor cover 13f covers the sides of the rotor core 13a. The rotor cover 13f and the two rotor support plates 13c isolate the rotor core 13a from fluids (refrigerants) such as water (waterproofing). The rotor support shaft 13d is cylindrical and extends in the axial direction. The rotor support shaft 13d is rotatably mounted on the shaft 12 via a bearing 14. In this embodiment, the bearing 14 is a sliding bearing. The impeller body 20a of the pump unit 20 is connected to the lower end of the rotor support shaft 13d. The connection between the rotor support shaft 13d and the impeller body 20a of the pump unit 20 is made by press-fitting and welding. Press-fitting ensures centering, while welding ensures connection strength. The configuration of the rotor support shaft 13d and the impeller body 20a of the pump section 20 will be described later.

[0018] A stator 15 is positioned radially outward of the rotor 13, surrounding the rotor 13. The stator 15 is assembled to the inner circumferential surface of the first housing 11 by shrink-fitting. The stator 15 has a stator core 15a, an insulator 15b attached to the stator core 15a, and a plurality of coils 15c attached to the stator core 15a via the insulator 15b. The stator core 15a is constructed by stacking dozens of ring-shaped laminated steel sheets (electromagnetic steel sheets). A coil winding section is formed inside the stator core 15a for winding each coil 15c. The coil winding section extends from the stator core 15a toward the center.

[0019] The insulator 15b is made of a protective material such as resin. The insulator 15b covers the surface of the stator core 15a. In other words, the insulator 15b protects the coils 15c by covering the inner circumferential surface of the cylindrical stator core 15a and the surface of each coil winding section. The coils 15c are made of metal windings such as copper or aluminum. The coils 15c are wound around each coil winding section of the stator core 15a.

[0020] The coil lead wires 15d of coil 15c are connected to a busbar assembly 19 located above the stator 15. The busbar assembly 19 is connected to a control unit 30, which supplies three-phase AC power to each coil 15c. The energization from the busbar assembly 19 to each coil 15c generates a magnetic flux inside each coil 15c. The busbar assembly 19 will be described further later.

[0021] A partition wall member 16, which serves as a sealing member, is provided between the rotor 13 and the stator 15. Figure 5 is a perspective view of the partition wall member 16 from above. As shown, the partition wall member 16 has a shape like an inverted cup, and the upper part of the partition wall member 16 (first partition wall 16a) is supported by the shaft 12. The partition wall member 16 has a disc-shaped first partition wall 16a located on the upper side, a cylindrical second partition wall 16b extending downward from the outer peripheral edge of the first partition wall 16a, and a third partition wall 16c extending radially outward from the peripheral edge of the second partition wall 16b. The connection portion 16p between the second partition wall 16b and the third partition wall 16c is machined into a rounded shape. The partition wall member 16 is made of a metal or resin that has sealing properties. Figure 6 is a perspective view of the partition wall member 16 from below. Although it was explained that the partition member 16 has the shape of an inverted cup, it could also be said that the partition member 16 is hat-shaped.

[0022] A fourth partition wall 16d is provided on the periphery of the third partition wall 16c, extending upward. Furthermore, a flange-shaped fixing portion 16e is provided on the periphery of the fourth partition wall 16d, extending radially outward. The first partition wall 16a, the second partition wall 16b, the third partition wall 16c, the fourth partition wall 16d, and the fixing portion 16e form a continuous structure. Multiple holes 16f for passing screws (bolts) are formed in the fixing portion 16e. In this embodiment, six holes 16f are formed. The holes 16f are provided on the radially outward side of the fixing portion 16e.

[0023] As shown in Figure 5, multiple reinforcing members 16g are provided on the outer surface of the second partition wall 16b, connected to the upper surface of the third partition wall 16c. The reinforcing members 16g are provided at predetermined intervals in the circumferential direction of the second partition wall 16b. In this embodiment, the reinforcing members 16g are reinforcing ribs. The shape of the reinforcing rib 16g is a right triangle when viewed from the circumferential direction. The parts corresponding to opposite sides of the reinforcing rib 16g are connected to the outer surface of the second partition wall 16b. The parts corresponding to adjacent sides are connected to the upper surface of the third partition wall 16c. The parts corresponding to the right angles are chamfered to match the rounded shapes of the second partition wall 16b, the third partition wall 16c, and the connecting part 16p. The second partition wall 16b and the third partition wall 16c are connected at a right angle at the connecting part 16p.

[0024] The reinforcing ribs 16g are positioned between the coils 15c that make up the stator 15. Multiple reinforcing ribs 16g maintain the right-angle connection between the second partition wall 16b and the third partition wall 16c. If the partition wall member 16 is made of metal, the reinforcing ribs 16g are made of metal and connected to the partition wall member 16 by welding or adhesive. If the partition wall member 16 is made of resin, the reinforcing ribs 16g may be made of metal or resin. If the partition wall member 16 is made of resin and the reinforcing ribs 16g are made of metal, the reinforcing ribs 16g can be integrally molded and assembled when the partition wall member 16 is molded in a mold. If the partition wall member 16 is made of resin and the reinforcing ribs 16g are also made of resin, the reinforcing ribs 16g can be molded simultaneously when the partition wall member 16 is molded in a mold, or the reinforcing ribs 16g can be provided as a separate component and joined to the partition wall member 16 by welding. The metal reinforcing ribs 16g are positioned near the coil 15c, allowing heat transferred from the coil 15c through the space to be dissipated to the fluid located inside the partition member 16. The resin reinforcing ribs 16g can be molded simultaneously with the partition member 16 when it is molded in a mold, thus reducing costs.

[0025] A through-hole 16h for the shaft 12 is formed in the center of the first partition wall 16a. A cylindrical mounting body 16j is provided on the periphery of the through-hole 16h so as to extend upward from the through-hole 16h. As shown in Figure 7, the first partition wall 16a is attached to the shaft 12 by passing the shaft 12 through the mounting body 16j and the through-hole 16h. Figure 7 is a partially enlarged view of part A in Figure 2. By attaching the first partition wall 16a to the shaft 12, the disc-shaped first partition wall 16a is positioned above the rotor 13 so as to extend radially outward from the shaft 12, and the first partition wall member 16a covers the upper side of the cylindrical rotor 13.

[0026] Furthermore, as shown in Figure 2, a second partition wall 16b, extending downward from the outer peripheral edge of the first partition wall 16a, is located between the rotor 13 and the stator 15, with the second partition wall 16b separating the rotor 13 and the stator 15. In addition, as shown in Figure 13, the lower side of the stator 15 is covered by a third partition wall 16c and a fourth partition wall 16d, which extend radially outward from the lower peripheral edge of the second partition wall 16b. The fourth partition wall 16d is fixed to the first housing 11 by a fixing portion 16e that extends radially outward in a flange-like manner from the fourth partition wall 16d. Figure 13 is a partially enlarged view showing section C of Figure 2. In other words, the lower side of the partition wall member 16 is fixed to the first housing 11 by the fixing portion 16e.

[0027] As shown in Figure 7, an O-ring mounting groove 16m is formed on the outer circumferential surface of the shaft 12 at the point where the shaft 12 fits into the mounting body 16j. An O-ring 16k is installed in the O-ring mounting groove. The O-ring 16k seals the space between the shaft 12 and the mounting body 16j. The partition member 16 appropriately separates the rotor 13 and the stator 15, sealing the space and preventing fluid from leaking from the rotor 13 to the stator 15. The second partition 16b does not contact either the rotor 13 or the stator 15. That is, as shown in Figure 8, a gap c1 is formed between the second partition 16b and the rotor 13. Also, a gap c2 is formed between the second partition 16b and the stator 15. Figure 8 is a partially enlarged view showing part B of Figure 2.

[0028] As shown in Figure 7, an auxiliary member 17 is positioned between the first partition wall 16a of the partition wall member 16 and the upper part 11b of the first housing 11. In Figure 7, the reference numeral f2 indicates the lower surface of the auxiliary member 17 (the contact surface that contacts the partition wall member 16). As shown in Figure 5, the auxiliary member 17 is disc-shaped. A through hole 17a is formed in the center of the auxiliary member 17. The mounting body 16j of the partition wall member 16 is inserted into the through hole 17a. In Figure 5, the reference numeral f1 indicates the top surface (the surface facing upwards) of the first partition wall 16a. By inserting the mounting body 16j into the through hole 17a, as shown in Figure 7, the top surface f1 of the first partition wall 16a and the contact surface f2 of the auxiliary member 17 are in contact with each other across their entire surfaces. Figure 9 is a perspective view showing the state in which the mounting body 16j of the partition wall member 16 is inserted into the through hole 17a of the auxiliary member 17 (the state in which the auxiliary member 17 is assembled on top of the partition wall member 16).

[0029] Furthermore, as shown in Figure 7, an annular recess 17b is formed on the upper surface of the auxiliary member 17. The recess 17b is formed by an annular guide wall w1 that surrounds the through hole 17a, with the through hole 17a at its center. The guide wall w1 is a wall that extends in the Z direction. The surface f3 enclosed by the guide wall w1 and facing the other side in the axial direction is the surface that receives the tip of the screw 18 (the lower end of the screw 18 in Figure 7). The surface f3 that receives the tip of the screw 13 may also be called the receiving surface f3. As shown in Figure 7, an annular space (gap) S is formed around the guide wall w1.

[0030] The lower surface (bottom surface) of the upper part 11b of the housing 11 is provided with a protrusion 11d that projects downward. The protrusion 11d is located below the shaft fixing part 11c. The protrusion 11d is annular. The protrusion 11d has a shaft fixing hole h1 in its center. As shown in Figure 7, the annular protrusion 11d is fitted into the annular recess 17b of the auxiliary member 17. In this fitting, the radial gap between the protrusion 11d and the recess 17b is very small. Because the protrusion 11d is fitted into the recess 17b, the auxiliary member 17 does not rattle radially. The protrusion 11d and the recess 17b are in a so-called spigot joint state. As shown by the white arrow (bidirectional arrow) in Figure 7, the auxiliary member 17 is movable axially (in the +Z direction and -Z direction) along the protrusion 11d.

[0031] Furthermore, as shown in Figure 3, the shaft fixing portion 11c of the housing 11 has multiple screw holes 11f that penetrate the upper part 11b of the housing 11 in the Z direction. Multiple screw holes 11f are formed in the circumferential direction with the shaft fixing hole h1 as the center. In this embodiment, three screw holes 11f are formed at equal intervals in the circumferential direction. A screw 18, which serves as a retaining member, is screwed into each screw hole 11f. As shown in Figure 5, the screw 18 is a headless micro-screw such as a fully threaded bolt or a plunger, and the entire screw 18 can be embedded in the screw hole 11f.

[0032] The lower end of the screw 18 is machined to have a chamfered or hemispherical shape. As shown in Figures 7 and 9, the lower end of the screw 18 protrudes downward from the screw hole 11f, and the lower end surface of the screw 18 is in contact with the receiving surface f3 of the recess 17b of the auxiliary member 17. A hexagonal hole or a star-shaped hole is formed at the other axial end (upper end) of the screw 18. A tool such as a hexagonal wrench or a star-shaped wrench can be inserted into the hexagonal or star-shaped hole. The screw 18 is screwed into the screw hole 11f from above the shaft fixing part 11c using a tool such as a hex wrench. At this time, whether or not the tip of the screw 18 is in contact with the receiving surface f3 of the recess 17b of the auxiliary member 17 can be determined, for example, by detecting a change in the screwing torque of the screw 18. In addition, whether or not the contact pressure (pressing force) between the tip (lower end) of the screw 18 and the receiving surface f3 is appropriate can also be determined by detecting a change in the screwing torque of the screw 18.

[0033] As shown in Figure 2, a gap S is formed around the auxiliary member 17. The gap S is an annular space centered on the shaft 12. The gap S is formed by the guide wall w1 of the auxiliary member 17, the upper part 11b of the first housing 11, the outer shell 11a of the first housing 11, and the other axial surface (top surface) of the stator 15. The busbar assembly 19 is housed in a radially outer position within the gap S, that is, near the inner surface of the outer shell 11a of the first housing 11.

[0034] The busbar assembly 19 has an annular assembly body 19a extending along the inner surface of the outer shell 11a of the first housing 11, a coil connection portion 19b, and a substrate-side projection 19c. The coil connection portion 19b and the substrate-side projection 19c are paired. In this embodiment, three such pairs are provided. The coil connection portion 19b includes a busbar (conductive rod) connected to a coil lead wire 15d extending from the coil 15c of the stator 15. As shown in Figure 2, the coil connection portion 19b is positioned radially inward, that is, toward the guide wall w1 of the auxiliary member 17.

[0035] By positioning the coil connection portion 19b radially inward, the tip of the coil connection portion 19b overlaps with the rotor 13 and the auxiliary member 17 when viewed from the axial direction. Because the coil connection portion 19b overlaps with the rotor 13 and the auxiliary member 17, there is no need to expand the air gap S that accommodates the coil connection portion 19b in the radial direction. By housing the coil connection portion 19b and the auxiliary member 17 in the air gap S, the radial miniaturization of the first housing 11 can be achieved. The air gap S is a space formed in the axial direction. By effectively utilizing the air gap S, the radial miniaturization of the first housing 11 is achieved. Furthermore, since the coil connection portion 19b is positioned lower than the height of the guide wall w1 of the auxiliary member 17, it is possible to suppress the axial enlargement of the first housing 11.

[0036] As shown in Figures 2 and 3, the substrate-side protrusion 19c is positioned inside the through-hole 11g formed in the upper part 11b of the first housing 11. In this embodiment, three through-holes 11e are formed in the upper part 11b of the first housing 11. A substrate-side protrusion 19c is positioned in each through-hole 11g. The substrate-side protrusion 19c is provided with a connection terminal 19d that connects to the busbar of the coil connection part 19b. As shown in Figure 3, the connection terminal 19d protrudes upward from the substrate-side protrusion 19c. Because the connection terminal 19d protrudes upward from the substrate-side protrusion 19c, when the control unit 30 is assembled to the upper part 11b of the first housing 11, the tip of the connection terminal 19d is electrically connected to the control unit 30.

[0037] (Pump section 20) As shown in Figures 2 and 13, the pump unit 20 is housed in a pump housing 20h located below the motor unit 10. As shown in Figure 10, the pump unit 20 is positioned in the center of the second housing 21 that forms the pump housing 20h. The second housing 21 has a support portion 23 that supports the lower end 12b of the shaft 12. Figure 10 is a perspective view of the pump unit 20 seen from above, Figure 11 is a perspective view of the second housing 21 that houses the pump unit 20 seen from below, and Figure 12 is an exploded perspective view of the second housing 21 and the pump unit 20 seen from the other axial side (above).

[0038] As shown in Figure 10, the second housing 21 has a second opening 21a facing the +Z direction. A flange 21m extending radially outward is provided on the edge (outer circumference) of the second opening 21a. A second surface 21n facing the +Z direction is formed on the flange 21m. The second surface 21n is a flat surface without any steps. In addition, a plurality of bolt holes 21p are formed on the flange 21m. The bolt holes 21p are formed at predetermined intervals in the circumferential direction of the flange 21m. In this embodiment, six bolt holes 21p are formed.

[0039] As shown in Figure 2, the flange 21m of the second housing 21 and the flange 11m of the first housing 11 are fastened together by bolts 24, with the fixing portion 16e of the bulkhead member 16 in between. O-rings 11j, 11j are located above and below the fixing portion 16e of the bulkhead member 16, respectively. As shown in Figure 13, the fastening of the flange 21m of the second housing 21 and the flange 11m of the first housing 11 results in the second surface 21n of the flange 21m and the first surface 11n of the flange 11m being in surface contact with each other, with the fixing portion 16e of the bulkhead member 16 in between.

[0040] By sandwiching the fixing portion 16e of the partition member 16 between the flange 11m of the first housing 11 and the flange 21m of the second housing 21, and fixing the flange 21m to the flange 21m, the fixing portion 16e (lower side of the partition member 16) of the partition member 16 can be fixed to the housing H. In other words, as described above, the upper side of the partition member 16 (first partition 16a) is fixed to the shaft 12, and the lower side of the partition member 16 (fixing portion 16e) is fixed to the housing H. By fixing the upper side of the partition member 16 to the shaft 12 and the lower side of the partition member 16 to the housing H, the rigidity and shape stability of the partition member 16 are improved. Improved rigidity and shape stability make it possible to make the partition member 16 thinner. Furthermore, since O-rings 11j, 11j are located above and below the fixing portion 16e of the partition member 16, the fixing portion 16e (the lower side of the partition member 16) can be sealed.

[0041] Furthermore, as shown in Figures 2 and 11, the second housing 21 has an inlet 25 connected to the pump housing 20h and a discharge port 26 located on the outer circumference of the pump housing 20h. The inlet 25 consists of a pipe 25a located coaxially with the central axis J. The inlet 25 is located on one axial end (lower end) of the shaft 12. The inlet 25 is connected to a fluid supply passage (not shown) and draws fluid from the fluid supply passage into the center of the pump housing 20h. The diameter of the inlet 25 is the same as that of the discharge port 26. The inlet 25 is provided with a support portion 23, which will be described later.

[0042] The discharge port 26 consists of a pipe 26a located parallel to the central axis J. The pipe 26a (discharge port 26) is located outside the flange 21m of the second housing 21. The lower side of the pipe 26a is open (open in the -Z direction), as shown in Figures 2 and 11. The upper side of the pipe 26a is closed. A communication port 26b is formed on the side of the pipe 26a. The communication port 26b is connected to the outlet side of the discharge flow path 21j in the pump housing 20h. The lower end of the pipe 26a (discharge port 26) is connected to a flow path (not shown), and discharges the fluid in the pump housing 20h into that flow path.

[0043] As shown in Figure 11, the discharge channel 21j is formed along the circumferential direction of the outer circumference of the second housing 21. The discharge channel 21j is formed as part of the second housing 21. The discharge channel 21j forms the inner surface of the pump housing 20h (Figure 10). As shown in Figure 2, the cross-section (cross-section perpendicular to the direction of fluid flow) of the discharge channel 21j is semicircular. The semicircular discharge channel 21j forms a curved section leading to the outermost diameter of the second housing 21. The discharge channel 21j collects the fluid sent radially outward from the pump section 20 and directs the fluid toward the discharge port 26.

[0044] As shown in Figures 12 and 13, the bottom 21c of the second housing 21 is flat. The outer circumference of the bottom 21c is connected to the inner circumference of the discharge passage 21j. A tubular projection 21d is provided in the center of the bottom 21c, which is connected to the pipe body 25a of the inlet 25. The projection 21d extends downward from the center of the bottom 21c. An inner groove 21e is formed inside the projection 21d along the circumferential direction. Since the inner diameter of the inner groove 21e is larger than the inner diameter of the pipe body 25a, the connection between the inner groove 21e and the pipe body 25a is stepped. Part of the pump section 20 is located in the inner groove 21e. The second housing 21 also has a curved section from the inlet 25 to the outermost flange 11m side.

[0045] As shown in Figures 10 and 13, a stepped portion 21f is formed on the upper inner circumference of the second housing 21 along the circumferential direction of the second housing 21. The stepped portion 21f has a first wall surface 21g facing radially inward and a second wall surface 21h facing in the other axial direction. The first wall surface 21g constitutes the inner circumferential surface of the flange 21m of the second housing 21. The first wall surface 21g is continuous with the second surface 21n of the flange 21m. The second wall portion 21h is located above the discharge passage 21j.

[0046] The third partition wall 16c and the fourth partition wall 16d of the partition wall member 16 are located on the stepped portion 21f. More specifically, as shown in Figure 13, the third partition wall 16c of the partition wall member 16 is located on the second wall surface 21h, and the fourth partition wall 16d of the partition wall member 16 is located on the first wall surface 21g. The lower portion of the partition wall member 16 (the third partition wall 16c and the fourth partition wall 16d) is located on the stepped portion 21f, thereby ensuring the shape stability of the lower portion of the partition wall member 16.

[0047] As shown in Figure 2, the pump section 20 is connected to the lower side of the rotor 13. In this embodiment, the pump section 20 is an impeller. In this embodiment, the impeller constituting the pump section 20 is made of metal. However, the impeller may be made of resin. As shown in Figure 12, the pump section 20 has an impeller body 20a, a shroud 20b, and a plurality of blades 22c. The impeller body 20a is disc-shaped with a central axis J at its center. A first through hole 20d is formed in the center of the impeller body 20a. A cylindrical fitting body 20e extending upward is formed on the edge of the first through hole 20d.

[0048] As shown in Figure 13, the pump unit 20 is connected to the rotor support shaft 13d of the rotor 13, so that the pump unit 20 rotates in conjunction with the rotation of the rotor 13. More specifically, one axial end (lower end) 13e of the sleeve-shaped rotor support shaft 13d is press-fitted into the inside of the fitting body 20e of the impeller body 20a. Furthermore, this fitting portion is welded. The impeller body 20a and the rotor support shaft 13d are connected by press-fitting and welding. The inner diameter of the fitting body 20e is approximately the same as or slightly smaller than the inner diameter of the pipe body 25a of the intake port 25.

[0049] As shown in Figure 12, the shroud 20b is a separate component from the impeller body 20a. The shroud 20b is positioned below the impeller body 20a with a gap between them. The shroud 20b is a disc shape, almost identical in shape to the impeller body 20a. A second through-hole 20f is formed in the center of the shroud 20b. A cylindrical guide body 20g extending downward is provided at the edge of the second through-hole 20f. Reference numeral 20j indicates the connection portion between the second through-hole 20f and the guide body 20g. The connection portion 20j has a rounded shape to smooth the fluid flow. As shown in Figure 13, the inner diameter of the guide body 20g is the same as the inner diameter of the pipe 25a of the intake port 25.

[0050] As shown in Figure 13, the guide body 20g is positioned to fit into an annular inner groove 21e formed inside the projection 21d of the intake port 25. However, since the guide body 20g rotates together with the shroud 20b, it does not come into contact with the inner groove 21e. In other words, there is a radial gap between the guide body 20g and the inner groove 21e. Also, the lower surface of the shroud 20b faces the bottom 21c of the second housing 21, but does not come into contact with the bottom 21c. In other words, there is an axial (Z-direction) gap between the lower surface of the shroud 20b and the bottom 21c.

[0051] As shown in Figure 12, the impeller body 20a is spaced axially apart from the shroud 20b, and the blades 20c are located between the impeller body 20a and the shroud 20b. The blades 20c are strip-shaped metal pieces curved in one direction. In this embodiment, seven blades 20c are arranged at regular intervals in the circumferential direction, with the same curvature direction for each blade 20c. Each blade 20c extends from the second through-hole 20f of the shroud 20b to the outer edge of the shroud 20b. The bottom of each blade 20c is fixed to the shroud 20b by welding. The top of each blade 20c is also fixed to the impeller body 20a by welding. The impeller body 20a and the shroud 20b are connected to each other via multiple blades 20c.

[0052] As the rotor 13 rotates, the pump unit (impeller) 20 rotates, and the centrifugal force of the pump unit 20 pushes the fluid in the pump housing 20h outwards to the outer circumference of the pump unit 20, where it is discharged through the discharge channel 21j and out of the discharge port 26 (OUT in Figure 2). When fluid is discharged from the discharge port 26, a negative pressure is created inside the pump housing 20h, causing fluid to be drawn into the pump housing 20h from the intake port 25 (IN in Figure 2). Fluid is continuously pumped out of the pump unit 20 by a similar action. The inside of the pump housing 20h and the space in which the rotor 13 is housed are in communication. Therefore, as the pump unit 20 rotates, some of the fluid in the pump housing 20h flows into the rotor 13. However, since the rotor 13 and the stator 15 are separated and sealed by the partition member 16, the fluid inside the rotor 13 does not flow (leak) into the stator 15. Furthermore, pressure fluctuations constantly occur within the pump housing 20h due to the fluid flow (discharge and suction). These pressure fluctuations also act on the partition wall member 16 facing the inside of the pump housing 20h.

[0053] As shown in Figures 2 and 13, a support portion 23 is positioned at the axial center of the pump section 20. The support portion 23 supports the lower end 12b of the shaft 12 (one side in the axial direction). The support portion 23 has a shaft fitting portion 23a and a plurality of support legs 23b. As shown in Figures 13 and 14, the shaft fitting portion 23a is located inside the fitting body 20e of the impeller body 20a. A first recess 23c is formed on the end face of the shaft fitting portion 23a on the other side in the axial direction (upper side), recessing toward the one side in the axial direction (lower side). The end portion 12b of the shaft 12 is fitted into the first recess 23c. Figure 14 is a partially enlarged view showing part A of Figure 13.

[0054] The first recess 23c is shaped to match the outer shape of the end 12b of the shaft 12. As can be seen from Figure 12, the outer shape of the end 12b of the shaft 12 consists of a circular cross-section and a notch (flat section) 12d. Therefore, the shape of the first recess 23c is shaped to match the circular cross-section and the notch 12d. If the end 12b of the shaft 12 is polygonal, the first recess 23c will also have a shape that matches the polygon. If the end 12b of the shaft 12 has a projection or keyway, the first recess 23c will also have a shape that matches the projection or keyway. Furthermore, the end 12b of the shaft 12 may be machined to snap-fit ​​into the first recess 23c. In this case, the two are joined simply by fitting the end 12b of the shaft 12 into the first recess 23c. In addition, the first recess 23c may be not just a simple hole, but may also have a stepped section created by cutting a wide groove.

[0055] As shown in Figures 12 and 14, a washer 14a is provided between the shaft fitting portion 23a and the bearing 14. The washer 14a prevents the bearing 14, which rotates with the rotor 13, from directly contacting and wearing down the fixed fitting portion 23a. Furthermore, as shown in the figures, a linear projection 14b is formed on a part of the inner circumference of the washer 14. This projection 14b is positioned so that when the end 12b of the shaft 12 passes through the washer 14, it fits into a notch 12d on the end 12b of the shaft 12. Because the projection 14b of the washer 14a is positioned on the notch 12d, the notch 12d also functions as an anti-rotation device for the washer 14a (preventing the washer 14a from rotating together).

[0056] As shown in Figure 14, a second recess 12c extending in the axial direction is formed at the end 12b of the shaft 12. In this embodiment, the second recess 12c is a screw hole. A fixing member 22, which fixes the shaft fitting portion 23a to the end 12b of the shaft 12, is screwed into the screw hole 12c. In this embodiment, the fixing member 22 is a screw or a bolt. A through hole 23e connected to the first recess 23c is formed in the center of the shaft fitting portion 23a. The through hole 23e is located below the first recess 23c. The fixing member (screw) 22 is screwed into the through hole 23e from one axial side (bottom side) to the other axial side (top side). The screw 22 has a screw head 22b at one axial end (bottom end). The screw head 22b has a screw end face 22a facing the other axial side (top side).

[0057] As shown in Figure 14, when the screw 22 is screwed into the screw hole 12c of the end 12b of the shaft 12 from the lower side of the through hole 23e, the screw head 22b comes into contact with the first end face 23g of the shaft fitting portion 23a. The first end face 23g is oriented axially to one side (downward) so as to face the screw end face 22a of the screw head 22b. In addition, an axial gap s3 is formed between the second end face 23h of the first recess 23c of the shaft fitting portion 23a and the end face 12e of the end 12b of the shaft 12. The second end face 23h is oriented axially to the other side (upward) so as to face the end face 12e of the end 12b of the shaft 12.

[0058] The screw head 22b of the screw 22 has a hole 22e (hexagonal hole, star-shaped hole, etc.) into which a tool for turning (screwing in) the screw 22 can be fitted. Tools such as hex wrenches and star wrenches can be fitted into the hole 22e. When the screw 22 is screwed into the screw hole 12c of the end 12b of the shaft 12 using a tool such as a hex wrench, and the support part 23 is fixed to the end 12b of the shaft 12, the end 12b of the shaft 12 is pulled toward the support part 23 (tension acts on the end 12 of the shaft 12 in the -Z direction). In other words, when the screw 22 is tightened, a force is generated in the axial direction that brings the end 12b of the shaft 12 and the support part 23 closer together. As shown in Figure 13, since the intake port 25 is located on the extension of one side of the axial direction of the screw 22, the screw 22 can be screwed into the end 12b of the shaft 12 using the intake port 25.

[0059] As shown in Figure 13, the shaft fitting portion 23a is supported by a plurality of support legs 23b located below the shaft fitting portion 23a. In this embodiment, three support legs 23b support the shaft fitting portion 23a. As shown in Figure 13, the support legs 23b extend from the inner wall surface of the pipe body 25a of the suction port 25 to the other axial direction. More specifically, the support legs 23b extend diagonally upward for a predetermined length from the inner wall surface of the pipe body 25a of the suction port 25, and then extend parallel to the central axis J. The upper ends of the support legs 23b pass through the first through hole 20d and the second through hole 20f of the pump section 20, respectively, and are connected to the first end face 23g of the shaft fitting portion 23a. In this embodiment, the three support legs 23b are arranged at equal intervals (120°) in the circumferential direction of the pipe body 25a with respect to the central axis J.

[0060] As shown in Figure 13, the end 12b of the shaft 12 is located above (on the other axial side) the third partition wall 16c of the partition wall member 16. In other words, the end 12b of the shaft 12 does not reach the pump section 20. Therefore, the shaft fitting portion 23a that supports the end 12b of the shaft 12 is located above (on the other axial side) the third partition wall 16c of the partition wall member 16, that is, it protrudes towards the motor housing portion 11h of the first housing 11.

[0061] In this embodiment, as shown in Figure 7, the second stage portion 12a of the shaft 12 is mounted on the shaft fixing portion 11c of the upper part 11b of the first housing 11. Therefore, as shown in Figure 13, the end portion 12b of the shaft 12 is fixed to the support portion 23 with a fixing member such as a screw 22. However, if the shaft 12 rotates together with the rotor 13, a bearing member may be newly attached to the support portion 23 instead of the screw 22. Also, the impeller constituting the pump portion 20 may be a trochoid pump, a gear pump, or a vane pump. Furthermore, in this embodiment, the shaft fitting portion 23a of the support portion 23 is located on the other axial side (upper side) of the pump portion 20, but the shaft 12 may be extended to be located on one axial side (lower side) of the pump portion 20.

[0062] (Control Unit 30) The control unit 30 supplies drive current to the motor unit 10. As shown in Figure 2, the control unit 30 includes a third housing 31 having a substrate housing chamber 30a, a substrate 32 housed in the substrate housing chamber 30a, and electronic components 33, etc. The third housing 31 is made of a metal such as aluminum or steel, which has excellent thermal conductivity. Cooling fins 31a and cable connection parts 31b are provided on the upper surface of the third housing 31. A sleeve 31c extending in one axial direction is formed on the lower side of the third housing 31. The sleeve 31c is fitted so as to cover the upper part 11b of the first housing 11 from the outside.

[0063] Electronic components 33 are mounted on the circuit board 32. The electronic components 33 include, for example, ICs, transistors, and capacitors. The electronic components 33 constitute a control circuit for controlling the electric pump 100. The circuit board 32 is mounted on the upper side of the upper part 11b of the first housing 11. Power is supplied from the circuit board 32 to the coil 15c of the stator 15 via the connection terminal 19d of the busbar assembly 19, thereby operating the stator 15.

[0064] (Effects / Actions) As shown in Figures 2, 10, and 12, the electric pump 100 of this embodiment has the lower end 12b of the shaft 12 supported by the support portion 23 of the pump housing 20h. By supporting the lower end 12b of the shaft 12 with the support portion 23 of the pump housing 20h, the cantilevered support state of the shaft 12 is eliminated. When the cantilevered support state of the shaft 12 is eliminated, it is possible to suppress bending and wobbling of the shaft 12 even when the centrifugal force of the rotor 13 is applied to the shaft 12.

[0065] In this embodiment, as shown in Figure 13, the support portion 23 that supports the shaft 12 has a shaft fitting portion 23a, which fits with the end of the shaft 12. By fitting the end of the shaft 12 into the shaft fitting portion 23a, the end 12b of the shaft 12 can be supported accurately without shifting radially. Furthermore, since the end 12b of the shaft 12 can be supported simply by fitting it into the shaft fitting portion 23a, the assembly work of the pump becomes easier.

[0066] In this embodiment, the shaft fitting portion 23a has a first recess 23c that is recessed on the upper side, and the shape of the first recess 23c matches the outer shape of the end portion 12b of the shaft 12. By matching the shape of the first recess 23c with the outer shape of the end portion 12b of the shaft 12, as shown in Figure 12, the shape of the end portion 12b of the shaft 12 and the shape of the first recess 23c can be made not only of a circular cross-section, but also of a notched shape 12d or a polygon. If the shape of the end portion 12b of the shaft 12 and the first recess 23c are made of a notched shape 12d or a polygon, it is possible to prevent the shaft 12 from rotating relative to the shaft fitting portion 23a when the end portion 12b of the shaft 12 is fitted into the first recess 23c.

[0067] In this embodiment, as shown in Figure 14, a fixing member 22, such as a screw, is fixed to the second recess 12c of the end 12d of the shaft 12 by passing through the through hole 23e of the support portion 23. By fixing the fixing member 22 to the shaft 12 from the support portion 23 side, it is possible not only to support the end 12b of the shaft 12, but also to prevent the end 12b of the shaft 12 from shifting or coming off.

[0068] In this embodiment, as shown in Figure 14, the screw 22, which is a fixing member, is screwed through the through hole 23e of the support part 23 and into the screw hole 12c of the end part 12d of the shaft 12, thereby suitably fixing the end part 12d of the shaft 12 to the support part 23 side. Furthermore, when the screw end face 22a of the screw 22 is in contact with the first end face 23g of the support part 23, there is a gap s3 between the end face 23d of the shaft 12 and the second end face 23h of the support part 23. Therefore, when the screw 22 is further tightened into the screw hole 12c from this state, the axial force of the screw 22 pulls the end part 12b of the shaft 12 towards the support part 23, generating axial tension in the shaft 12. This tension improves the rigidity of the shaft 12, so that the bending of the shaft 12 can be more suitably suppressed even when the centrifugal force of the rotor 13 is applied.

[0069] In this embodiment, as shown in Figure 3, the first housing 11 has an upper part 11b located above the stator 15 or rotor 13, and this upper part 11b has a shaft fixing part 11c, as shown in Figure 2. By fixing the end 12b of the shaft 12 to this shaft fixing part 11c, the shaft 12 will not detach (fall out) from the upper part 11b of the first housing 11 even if the shaft 12 is pulled in one axial direction by the axial force of the screw.

[0070] In this embodiment, as shown in Figure 7, the shaft fixing part 11c has a first stage s1, and the end portion 12a of the shaft 12 has a second stage 12a that faces the first stage s1 in the axial direction. The shaft fixing part 11c fixes the shaft 12 so that the second stage 12a and the first stage s1 face each other in the axial direction. By fixing the second stage 12a and the first stage s1 so that they face each other in the axial direction, when the screw 22 is screwed into the lower end portion 12b of the shaft 12, an axial force is generated in the screw 22, and the shaft 12 is pulled in one direction in the axial direction by the axial force. Even when the shaft 12 is subjected to tension that pulls it in one direction in the axial direction, the end portion 12b of the shaft 12 will not catch on the upper portion 11b of the first housing 11 and come off (fall out) from the shaft fixing part 11c. Therefore, by further increasing the tightening torque of the screw 22, it becomes possible to further increase the tension of the shaft 12, thereby further improving the rigidity of the shaft 12.

[0071] The stepped portion s1 and the second stepped portion 12a may have radial irregularities in some parts. Furthermore, the first stepped portion s1 may not only be formed on the upper edge of the shaft fixing hole h1, but may also be located in the middle of the shaft fixing hole h1 (upper part 11b), as in the case of inserting by resin molding. However, forming the first stepped portion s1 on the upper edge of the shaft fixing hole h1 makes processing easier and reduces processing time compared to forming it in the middle of the shaft fixing hole h1 (upper part 11b). This reduces manufacturing costs.

[0072] In this embodiment, as shown in Figure 2, the pump housing 20h has an intake port 25 located below the support portion 23. Therefore, the inside of the pump housing 20h can be directly viewed from this intake port 25. By inserting a tool or the like while visually viewing the support portion 23 inside the pump housing 20h from this intake port 25, the installation and tightening of fixing members such as screws 22 to the support portion 23 can be easily performed.

[0073] In this embodiment, as shown in Figures 4 and 10, the second housing 21 constituting the pump housing 20h has a second surface 21n that contacts the first surface 11n of the first housing 11 constituting the motor housing 11h. Because the first surface 11n and the second surface 21n are in surface contact, the stress on the pump housing 20h due to the axial force of the screw 22 can be received by the motor housing 11h side via the surface. This avoids stress concentration on the support portion 23. By avoiding stress concentration on the support portion 23, the durability of the pump housing 20h against stress is improved, allowing the shaft 12 to be suitably supported by the support portion 23. Furthermore, because stress concentration on the support portion 23 can be avoided, the tightening torque of the screw 22 can be sufficiently increased to further improve the rigidity of the shaft 12.

[0074] In this embodiment, as shown in Figures 11 and 13, the pump housing 20h has a curved portion 21j from the support portion 23 to the outermost diameter of the pump housing 20h. When the screw 22 is tightened and an axial force is generated, the pump housing 20h also receives stress due to the axial force via the support portion 23. Even when stress is applied to the pump housing 20h, because there is a curved portion 21j with a rounded shape between the support portion 23 that receives the axial force and the second surface 21n to which the pump housing 20h is joined, it is possible to avoid stress concentration in the pump housing 20h. Since stress concentration in the pump housing 20h can be avoided, the durability and reliability of the pump housing 20h are improved. Note that the curved portion 21j may be a curved portion with a curved shape at the corners as well as at the corners, up to the outermost diameter of the pump housing 20h.

[0075] In this embodiment, as shown in Figure 14, the end face 12e of the end 12b of the shaft 12 is located above the pump section 20, and the support section 23 is located in the motor housing section 11h. By positioning the support section 23 that supports the shaft 12 on the motor housing section 11h side, the length of the shaft 12 can be shortened. By shortening the length of the shaft 12, the amount of deflection of the shaft 12 can be reduced.

[0076] In this embodiment, the shaft 12 is fixed to the upper part 11b of the first housing 11 and has a non-rotating structure. However, there are also electric motors in which the shaft 12 rotates. In the case of a structure in which the shaft 12 rotates, if a bearing member is provided in the shaft fitting portion 23a, it is possible to prevent the shaft 12 from bending while rotatably supporting the end of the shaft 12, even if the shaft 12 rotates.

[0077] 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. For example, the first partition wall 16a of the partition wall member 16 and the auxiliary member 17 may be polygonal in shape, not just disc-shaped. Also, the recess 17b of the auxiliary member 17 and the protrusion 11d of the upper part 11b that fits therein may also be polygonal. Furthermore, the electric pump of this disclosure can have the following configuration.

[0078] (1) It is an electric pump, A shaft extending in the axial direction, A rotatable rotor located radially outward from the aforementioned shaft, A stator located radially outward from the rotor and surrounding the rotor, A pump section located on one axial side of the aforementioned shaft, The housing has a pump housing section that accommodates the pump section, The pump housing has a support portion that supports one end of the shaft on the axial side, and is an electric pump.

[0079] (2) The support portion has a shaft fitting portion, The shaft fitting portion fits with the end of the shaft, as described in (1). (3) The shaft fitting portion has a first recess that is recessed on the other axial side, The electric pump according to (2), wherein the shape of the first recess matches the outer shape of the end of the shaft.

[0080] (4) The support portion has a through hole that penetrates in the axial direction, The end of the shaft has a second recess that is recessed on the other side in the axial direction, The electric pump according to (1), wherein the end portion is supported by the support portion by a fixing member that passes through the through hole and is fixed to the second recess.

[0081] The second recess is a screw hole extending in the axial direction, The fixing member is a screw that is screwed into the screw hole, The support portion has a first end face facing one side in the axial direction and a second end face facing the other side in the axial direction. The screw has a threaded end face that faces the other side in the axial direction and contacts the first end face, The electric pump according to (4), wherein there is a gap between the shaft end face on one axial side of the end and the second end face.

[0082] (6) The housing has an upper part located on the other axial side of the stator or the rotor, The electric pump according to (1), wherein the upper part has a shaft fixing portion for fixing the other end of the shaft in the axial direction.

[0083] (7) The shaft fixing portion has a first stage portion, The electric pump according to (2), wherein the other end of the shaft on the axial side has a second stage that faces the first stage in the axial direction. (8) The pump housing has an intake port on one axial side of the support portion, and is an electric pump mounted on (1).

[0084] (9) The housing comprises a motor housing section for housing the stator and a pump housing section connected to the motor housing section. The electric pump according to (5), wherein the pump housing has a connecting surface that contacts the motor housing side with a surface. (10) The electric pump according to (5), wherein the pump housing has a curved portion from the support portion to the outermost diameter of the pump housing.

[0085] (11) The end face of the shaft is located on the other axial side of the pump section. The electric pump according to (1), wherein the support portion is located in the motor housing portion on the other axial side of the pump portion. (12) The shaft fitting portion has a bearing member, The end portion is fitted with the bearing member, as described in (2), for the electric pump. [Explanation of Symbols]

[0086] 100: Electric pump 10: Motor section 11: Housing 1 11b: Upper part 11c: Shaft fixing part 11h: Motor housing 11n: First face 12: Shaft 12a: Upper end of the shaft (second stage) 12b: Lower end of shaft 12c: Second recess (screw hole) 12d: Notch 12e: Shaft end face 13: Rotor 15: Status 20: Pump section 20h: Pump housing 21: Second Housing 21j: Music section 21n: Second face 22: Screws (fixing components) 22a: Screw end face 23: Support part 23a: Shaft fitting section 23c: First recess 23c 23d: End face 23e: Through hole 23g: 1st end surface 23h: 2nd end surface 23h: Pump housing 25: Inlet 30: Control Unit H: Housing s1: First section s3: Gap

Claims

1. It is an electric pump, A shaft extending in the axial direction, A rotatable rotor located radially outward from the aforementioned shaft, A stator located radially outward from the rotor and surrounding the rotor, A pump section located on one axial side of the aforementioned shaft, The housing has a pump housing section that accommodates the pump section, The pump housing has a support portion that supports one end of the shaft on the axial side, and is an electric pump.

2. The support portion has a shaft fitting portion, The electric pump according to claim 1, wherein the shaft fitting portion fits with the end of the shaft.

3. The shaft fitting portion has a first recess that is recessed on the other side in the axial direction, The electric pump according to claim 2, wherein the shape of the first recess matches the outer shape of the end of the shaft.

4. The support portion has a through hole that penetrates in the axial direction, The end of the shaft has a second recess that is recessed on the other side in the axial direction, The electric pump according to claim 1, wherein the end portion is supported by the support portion by a fixing member that passes through the through hole and is fixed to the second recess.

5. The second recess is a screw hole extending in the axial direction, The fixing member is a screw that is screwed into the screw hole, The support portion has a first end face facing one side in the axial direction and a second end face facing the other side in the axial direction. The screw has a threaded end face that faces the other side in the axial direction and contacts the first end face, The electric pump according to claim 4, wherein there is a gap between the shaft end face on one axial side of the end and the second end face.

6. The housing has an upper part located on the other axial side of the stator or the rotor, The electric pump according to claim 1, wherein the upper part has a shaft fixing portion for fixing the other end of the shaft in the axial direction.

7. The shaft fixing portion has a first stage portion, The electric pump according to claim 2, wherein the other end of the shaft on the axial side has a second stage that faces the first stage in the axial direction.

8. The electric pump according to claim 1, wherein the pump housing has an intake port on one axial side of the support portion.

9. The housing comprises a motor housing section for housing the stator and a pump housing section connected to the motor housing section. The electric pump according to claim 5, wherein the pump housing has a connecting surface that contacts the motor housing side with a surface.

10. The electric pump according to claim 5, wherein the pump housing has a curved portion from the support portion to the outermost diameter of the pump housing.

11. The end face of the shaft is located on the other axial side of the pump section. The electric pump according to claim 1, wherein the support portion is located in the motor housing portion on the other axial side of the pump portion.

12. The shaft fitting portion has a bearing member, The electric pump according to claim 2, wherein the end portion is fitted with the bearing member.

Images