pump

Abstract

To provide a pump which enables improvement of reliability of a stator.SOLUTION: One embodiment of a pump of the invention includes: a rotor which may rotate around a center axis; a stator assembly which is positioned at the radial outer side of the rotor and encloses the rotor; a pump part connected to one axial side of the rotor; a support member which is positioned at the radial inner side of the stator assembly and has a rotor housing part which houses the rotor therein; and a resin housing in which the stator assembly and the support member are molded. The rotor housing part has: a lid part which covers the rotor from the other axial side; and a cylindrical part which is positioned between the rotor and the stator assembly in a radial direction and is open to one axial side. The stator assembly has: an annular stator core; multiple coils attached to the stator core; and a stator cover which covers the multiple coils.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a pump. [Background technology]

[0002] Development of electric pumps in which the motor and pump are integrated in advance is underway. Patent Document 1 discloses a pump in which the motor and pump are integrated, and the stator is molded to ensure waterproofing of the stator. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5316917 Summary of the Invention [Problem to be solved by the invention]

[0004] As described in the prior art, when the stator is molded, the molding resin comes into direct contact with the coil, which can cause damage to the coil wire due to the heat and injection pressure during molding of the molding resin.

[0005] In view of the above circumstances, one object of the present invention is to provide a pump with an improved stator reliability. [Means for solving the problem]

[0006] One aspect of the pump of the present invention includes a rotor rotatable about a central axis, a stator assembly positioned radially outward of the rotor and surrounding the rotor, a pump section connected to one axial side of the rotor, a support member positioned radially inward of the stator assembly and having a rotor accommodating section that accommodates the rotor, and a resin housing that molds the stator assembly and the support member. The rotor accommodating section has a lid section that covers the rotor from the other axial side, and a cylindrical section positioned radially between the rotor and the stator assembly and opening to one axial side. The stator assembly has an annular stator core, a plurality of coils attached to the stator core, and a stator cover that covers the plurality of coils. [Effects of the Invention]

[0007] According to one aspect of the present invention, a pump with improved stator reliability can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a pump according to one embodiment. [Figure 2] FIG. 2 is a cross-sectional view of a pump according to one embodiment. [Figure 3] FIG. 3 is a partially enlarged view of FIG. [Figure 4] FIG. 4 is a partially enlarged view of FIG. [Figure 5] FIG. 5 is a partially enlarged view of FIG. [Figure 6] FIG. 6 is a partially enlarged view of FIG. [Figure 7] FIG. 7 is a perspective view of a stator assembly according to one embodiment. [Figure 8] FIG. 8 is a partial cross-sectional view of a modified pump. DETAILED DESCRIPTION OF THE INVENTION

[0009] Each figure shows an imaginary central axis J of a pump 1 according to an embodiment described below. 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." 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. In the following description, the side of the axial direction toward which the arrow of the Z axis points (+Z side) will be referred to as the "upper side," and the side of the axial direction opposite to the side toward which the arrow of the Z axis points (-Z side) will be referred to as the "lower side."

[0010] In this embodiment, the lower side corresponds to the “one axial side,” and the upper side corresponds to the “other axial side.” Note that the terms “upper side” and “lower side” are simply names used to describe the relative positional relationship of each part, and the actual positional relationship may be one other than the positional relationship indicated by these names.

[0011] Fig. 1 is a perspective view of pump 1. Fig. 2 is a cross-sectional view of pump 1. Figs. 3, 4, 5, and 6 are enlarged views of portions of Fig. 2. For the sake of explanation, Fig. 2 shows cross sections at different circumferential positions on both the left and right sides of the central axis J.

[0012] 2, the pump 1 of this embodiment includes a motor 3, a pump unit 60, a support member 10, a fixed shaft 40, a circuit board 80, and a case 2. The motor 3 includes a rotor 50 that is rotatable about a central axis J, and a stator assembly 75 that is positioned radially outward of the rotor 50 and surrounds the rotor 50. That is, the pump 1 includes the rotor 50 and the stator assembly 75.

[0013] The pump 1 of this embodiment is a water pump that pumps water. The pump 1 is driven by a motor 3 to rotate a pump unit 60, thereby drawing in water (liquid) from an inlet pipe 26 and discharging it from an outlet pipe 27 (see FIG. 1).

[0014] As shown in Figure 2, the case 2 houses the motor 3, pump unit 60, support member 10, fixed shaft 40, and circuit board 80. The interior of the case 2 is divided into a flow path area A2 through which water (liquid) passes and a waterproof area A1 that is sealed off from water. The rotor 50, fixed shaft 40, and pump unit 60 are arranged in the flow path area A2. The stator assembly 75 and circuit board 80 are arranged in the waterproof area A1. The flow path area A2 and the waterproof area A1 are separated by the support member 10.

[0015] The case 2 has a resin housing (motor housing) 30, a board cover 28, and a pump cover 20. That is, the pump 1 is equipped with the resin housing 30, the board cover 28, and the pump cover 20. The board cover 28 is joined to the upper end of the resin housing 30. Meanwhile, the pump cover 20 is joined to the lower end of the resin housing 30. In this way, the resin housing 30, the board cover 28, and the pump cover 20 are fixed to one another.

[0016] The resin housing 30 has an embedding portion 32 in which the stator assembly 75 and the support member 10 are molded and embedded. That is, the resin housing 30 is formed by insert molding, in which the stator assembly 75 and the support member 10 are inserted. In this way, the resin housing 30 holds the stator assembly 75 and the support member 10. The resin housing 30 surrounds the stator 70, the rotor 50, and the rotor accommodating portion 12 from the radial outside.

[0017] 1, the outer peripheral surface 30a of the resin housing 30 is circular when viewed in the axial direction. A connector portion 39 is provided on the outer peripheral surface 30a of the resin housing 30. That is, the resin housing 30 has the connector portion 39. The connector portion 39 protects the terminals 8 that are connected to the external device 7.

[0018] 2, the upper end of the resin housing 30 is provided with an upward-facing housing upper surface 30g and an enclosing cylindrical portion 38 extending upward from the outer edge of the upper surface 30g. Meanwhile, the lower end of the resin housing 30 is provided with a cylindrical retaining cylindrical portion 31 centered on the central axis J. The resin housing 30 is joined to the board cover 28 at the enclosing cylindrical portion 38, and is joined to the pump cover 20 at the retaining cylindrical portion 31.

[0019] The housing upper surface 30g faces the circuit board 80 in the vertical direction. A boss that supports the circuit board 80 from below is provided on the housing upper surface 30g. The surrounding cylinder portion 38 has a cylindrical shape centered on the central axis J. The surrounding cylinder portion 38 surrounds the circuit board 80 from the radially outer side.

[0020] The board cover 28 has a plate-shaped cover body 28a extending along a plane perpendicular to the central axis J, and guide ribs 28b provided on the underside of the cover body 28a. The cover body 28a is circular and centered on the central axis J. The outer diameter of the cover body 28a approximately matches the outer diameter of the plastic housing 30. The guide ribs 28b extend in the circumferential direction. The guide ribs 28b are positioned slightly radially inward from the outer edge of the cover body 28a. The outer peripheral surface of the guide ribs 28b fits into the inner peripheral surface of the surrounding cylindrical portion 38 of the plastic housing 30. This positions the board cover 28 relative to the plastic housing 30.

[0021] An area on the lower surface of the cover body 28a that is located radially outward from the guide rib 28b comes into contact with the upper end surface of the surrounding cylindrical portion 38 of the resin housing 30. The lower surface of the cover body 28a and the upper end surface of the surrounding cylindrical portion 38 are welded to each other.

[0022] In the welding process, the board cover 28 is rotated while its underside is pressed against the resin housing 30. In the welding process, the contact portions between the board cover 28 and the resin housing 30 are melted and solidified by frictional heat, thereby joining them. That is, the board cover 28 and the resin housing 30 are joined by spin welding. Note that the board cover 28 and the resin housing 30 may also be welded by other welding means, such as ultrasonic welding or laser welding.

[0023] The circuit board 80 is disposed above (the other axial side of) the stator assembly 75. That is, the circuit board 80 is disposed above the stator 70. The circuit board 80 is accommodated in a space surrounded by the radially inner side of the surrounding cylindrical portion 38 of the resin housing 30, the housing upper surface 30g, and the board cover 28.

[0024] The circuit board 80 has a plate-shaped board body 81 along a plane perpendicular to the central axis J, and a heat generating element 82 mounted on an upper surface 81a (the surface on the other axial side) of the board body 81. In addition to the heat generating element 82, the circuit board 80 also has a plurality of elements (not shown) mounted on the upper surface 81a or the lower surface 81b of the board body 81.

[0025] The board body 81 has first through holes (through holes) 81h and second through holes 81k that penetrate through the thickness direction. That is, the first through holes 81h and second through holes 81k are provided in the circuit board 80. The coil wires 73a extending upward from the stator assembly 75 are inserted into the first through holes 81h and connected to the board body 81 by soldering. The first ends 8a of the terminals 8 are inserted into the second through holes 81k and connected to the board body 81 by soldering. A plurality of first through holes 81h and second through holes 81k are provided in the board body 81.

[0026] The heat-generating element 82 is disposed on the central axis J. The heat-generating element 82 refers to an element mounted on the board body 81 that generates heat and reaches a high temperature during operation. When the circuit board 80 has multiple elements, the heat-generating element 82 generates more heat than the other elements. Examples of the heat-generating element 82 include a switching element, a capacitor, a field-effect transistor, a driver integrated circuit for driving a field-effect transistor, and a power supply integrated circuit.

[0027] The support member (shield member) 10 is made of a non-magnetic material. In this embodiment, the support member 10 is made of resin. The support member 10 has a rotor accommodating portion 12 and a flange portion 11.

[0028] The rotor accommodating portion 12 is located radially inside the stator assembly 75. In other words, the rotor accommodating portion 12 is located radially inside the stator 70. The rotor accommodating portion 12 is cylindrical and surrounds the central axis J, opening downward. The rotor accommodating portion 12 accommodates the rotor 50 therein. The rotor accommodating portion 12 has a lid portion 12a that covers the rotor 50 from above, and a cylindrical portion 12b that extends downward from the lid portion 12a.

[0029] The lid portion 12a is disk-shaped and centered on the central axis J. The lid portion 12a covers the rotor 50 from above (the other axial side). A holding portion 12c is provided in the center of the lid portion 12a when viewed from the axial direction. The holding portion 12c is a portion that holds the upper end of the fixed shaft 40. The holding portion 12c protrudes downward more than the other portions of the lid portion 12a.

[0030] The cylindrical portion 12b extends downward from the radially outer peripheral edge of the cover portion 12a and is connected to the radially inner peripheral edge of the flange portion 11. The cylindrical portion 12b is located between the rotor 50 and the stator assembly 75 in the radial direction. That is, the cylindrical portion 12b is located between the rotor 50 and the stator 70 in the radial direction. The cylindrical portion 12b is open downward.

[0031] According to this embodiment, the rotor accommodating section 12 accommodates the rotor 50 therein. The rotor accommodating section 12 also has a lid section 12a that covers the rotor 50 from above, and a cylindrical section 12b that surrounds the rotor 50 and opens downward. As a result, the rotor accommodating section 12 can separate and seal the rotor 50 and the stator 70 while ensuring a structure that connects the pump section 60 to the underside of the rotor 50, and can prevent the liquid (water) pumped by the pump section 60 from coming into contact with the stator 70.

[0032] The flange portion 11 has an annular shape surrounding the central axis J. The flange portion 11 extends radially outward from a lower end (one axial side) of the rotor accommodating portion 12. The flange portion 11 is located below the stator 70. A surface of the flange portion 11 facing downward (a third contact surface 10f described later) is welded to the pump cover 20.

[0033] The outer peripheral surface of the flange portion 11 is covered by the retaining cylindrical portion 31 of the resin housing 30. That is, at least a portion of the inner peripheral surface of the retaining cylindrical portion 31 contacts the outer peripheral surface of the flange portion 11. In this embodiment, the support member 10 is embedded in the resin housing 30 together with the stator assembly 75.

[0034] A portion of the upper surface and the outer circumferential surface of the flange portion 11 are embedded in the resin housing 30, and the lower surface is exposed from the resin housing 30. The resin housing 30 has a stepped surface 32a in the portion where the upper surface of the flange portion 11 is embedded. That is, the resin housing 30 has the stepped surface 32a that contacts the upper surface of the flange portion 11 (the surface facing the other axial direction). The resin housing 30 supports the flange portion 11 in the axial direction at the stepped surface 32a.

[0035] 1, the outer peripheral surface of the flange portion 11 is provided with a plurality of protrusions 11e aligned in the circumferential direction. The inner peripheral surface of the holding cylinder portion 31 is provided with a plurality of recesses 31e into which the protrusions 11e are inserted. The recesses 31e are formed when the resin housing 30 is molded by filling the protrusions 11e with molten resin surrounding the outer peripheral surface of the flange portion. Therefore, the protrusions 11e and the recesses 31e are in close contact with each other.

[0036] A positioning rib 11d is provided on the underside of the flange portion 11 (the surface facing one axial side). The positioning rib 11d protrudes downward from the underside of the flange portion 11. The positioning rib 11d extends in the circumferential direction around the central axis J. The outer peripheral surface of the positioning rib 11d facing radially outward is fitted into the inner peripheral surface of the pump cover 20. The positioning rib 11d aligns the axes of the pump cover 20 and the support member 10 relative to one another. Note that a small gap may be provided between the outer peripheral surface of the positioning rib 11d and the inner peripheral surface of the pump cover 20. In this case, the pump cover 20 and the support member 10 are aligned with each other while allowing for assembly errors within the gap.

[0037] 2, the fixed shaft 40 extends in the axial direction. The fixed shaft 40 has a cylindrical shaft main body 41 that extends in the axial direction around a central axis J, and a holding member 42 that is disposed on the other axial side of the shaft main body 41. The shaft main body 41 and the holding member 42 are made of a metal material with excellent thermal conductivity.

[0038] A threaded hole 41h is provided in the lower end surface of the shaft main body 41. The threaded hole 41h extends in the axial direction about the central axis J. A retaining screw 69 is inserted into the threaded hole 41h. The retaining screw 69 prevents the pump portion 60 from falling off downward.

[0039] A retaining recess 61 is provided in the center of the pump portion 60. The retaining recess 61 opens downward. The retaining recess 61 has a retaining surface 61p facing downward as its bottom surface. The retaining screw 69 described above is placed inside the retaining recess 61. The seating surface of the head of the retaining screw 69 and the retaining surface 61p of the retaining recess 61 of the pump portion 60 face each other in the axial direction via a washer 68.

[0040] The lower end surface of the shaft main body 41, the retaining screw 69, and the washer 68 are exposed to the flow path of the fluid pumped by the pump unit 60. Therefore, the fixed shaft 40, the retaining screw 69, and the washer 68 come into contact with the water (liquid) flowing into the pump unit 60 and are water-cooled. As a result, heat transferred from the circuit board 80 to the fixed shaft 40 can be released into the water, thereby efficiently cooling the circuit board 80.

[0041] As shown in FIG. 5, the retaining member 42 is disposed above (on the other axial side of) the shaft main body 41. The retaining member 42 has a retaining member main body 42b and a retaining member flange (flange portion) 42f extending radially outward from the retaining member main body 42b. A retaining hole 42h that opens downward is provided in the retaining member main body 42b. The upper end of the shaft main body 41 is fitted into the retaining hole 42h. This fixes the shaft main body 41 to the retaining member 42.

[0042] According to this embodiment, the fixed shaft 40 has a shaft main body 41 and a holding member 42 that are fixed to each other. Therefore, the fixed shaft 40 can be manufactured by assembling the shaft main body 41 and the holding member 42 that are manufactured separately, and the fixed shaft 40 can be manufactured inexpensively.

[0043] The holding member 42 is embedded in the lid portion 12a of the support member 10 by insert molding. More specifically, the holding member flange portion 42f of the holding member 42 is embedded in the holding portion 12c of the lid portion 12a. This allows the fixed shaft 40 to be supported by the lid portion 12a. According to this embodiment, by embedding the holding member flange portion 42f in the holding portion 12c, the holding member flange portion 42f is caught by the holding portion 12c over a large area in the axial direction. This makes it possible to prevent the holding member flange portion 42f from slipping downward from the holding portion 12c.

[0044] The holding member flange 42f extends radially outward relative to the shaft main body 41. The holding member flange 42f is surface-treated to enhance adhesion to the resin material that constitutes the holding portion 12c. This prevents moisture from penetrating the interface between the holding member 42 and the holding portion 12c. Therefore, moisture does not reach the upper side of the lid portion 12a from inside the rotor accommodating portion 12.

[0045] The holding member 42 has an exposed portion 42a that is exposed above the lid portion 12a (the other axial side). That is, the fixed shaft 40 has the exposed portion 42a. The exposed portion 42a is on the upper surface of the holding member main body 42b and extends along a plane that is perpendicular to the central axis J. The exposed portion 42a extends along a plane that is perpendicular to the central axis J. The exposed portion 42a faces the circuit board 80 located above the lid portion 12a.

[0046] A thermally conductive material 9 is sandwiched between the exposed portion 42a and the circuit board 80. The thermally conductive material 9 in this embodiment is a sheet-like heat dissipation sheet. The thermally conductive material 9 is made of a silicon-based material or the like. The thermally conductive material 9 may also be heat dissipation grease or heat dissipation gel.

[0047] The thermally conductive material 9 is in contact with the exposed portion 42a. The thermally conductive material 9 is also in contact with the lower surface 81b of the board body 81 of the circuit board 80. The thermally conductive material 9 transfers the heat of the circuit board 80 to the fixed shaft 40.

[0048] According to this embodiment, the thermally conductive material 9 transfers heat generated in the circuit board 80 to the fixed shaft 40 via the thermally conductive material 9. The fixed shaft 40 has a sufficiently large heat capacity compared to the heat generating element 82 and the board main body 81. Furthermore, the fixed shaft 40 is cooled by contact with the water (liquid) discharged by the pump unit 60. Therefore, according to this embodiment, the circuit board 80 can be cooled effectively, and the operational reliability of the circuit board 80 can be improved.

[0049] According to this embodiment, the circuit board 80 is cooled using the fixed shaft 40 provided inside the pump 1. This allows the overall pump 1 to be made smaller in the axial direction than when a heat sink is also used above the circuit board 80. In addition, compared to when a heat sink is used, the sealing structure around the heat sink can be omitted, reducing manufacturing costs.

[0050] In this embodiment, the heating element 82, the thermally conductive material 9, and the exposed portion 42a overlap one another when viewed in the axial direction. This allows the heat generated by the heating element 82 to be transferred over the shortest distance to the exposed portion 42a of the fixed shaft 40 via the substrate main body 81 and the thermally conductive material 9, and the heating element 82 can be efficiently cooled by the fixed shaft 40.

[0051] In this embodiment, the case where the heating element 82 is mounted on the upper surface 81a of the substrate main body 81 has been described. In this case, the heat of the heating element 82 is transferred to the thermally conductive material 9 via the circuit board. In contrast, as shown as a modified example in FIG. 8, Heating element 182 In this modification, the thermal conductive material 109 may be mounted on the lower surface 81b (the surface on one side in the axial direction) of the substrate body 81. Heating element 182 This means that Heating element 182 The heat can be directly transferred to the thermal conductive material 109, Heating element 182 The cooling efficiency can be improved.

[0052] 2, the rotor 50 is accommodated inside the rotor accommodating portion 12. The rotor 50 is rotatable about a central axis J. The rotor 50 includes a rotor core 51, a magnet 52, a first covering portion 54, and a resin portion 53.

[0053] The rotor core 51 is annular and surrounds the central axis J. A fixed shaft 40 passes axially through the radially inner side of the rotor core 51. The magnets 52 are fixed to the rotor core 51. In this embodiment, the magnets 52 are arranged on the outer peripheral surface of the rotor core 51. For example, a plurality of magnets 52 are provided at intervals in the circumferential direction. The first covering portion 54 fixes the rotor core 51 and the plurality of magnets 52 to each other. The first covering portion 54, the rotor core 51, and the magnets 52 constitute a rotor assembly 55.

[0054] The resin part 53 has a cylindrical shape that surrounds the central axis J and extends in the axial direction. The fixed shaft 40 passes through the radially inner side of the resin part 53 in the axial direction. The fixed shaft 40 is inserted into the radially inner side of the resin part 53. The fixed shaft 40 supports the inner circumferential surface of the resin part 53, thereby rotatably supporting the rotor 50.

[0055] The resin portion 53 has a second covering portion 53a that embeds and holds the rotor assembly 55, and an extension portion 53b that extends downward from the second covering portion 53a. The second covering portion 53a has a portion that is located radially between the fixed shaft 40 and the rotor core 51. The lower end of the extension portion 53b protrudes downward beyond the rotor accommodating portion 12. A retaining recess 61 is provided at the lower end of the extension portion 53b. As described above, a retaining screw 69 that prevents the rotor 50 and the pump portion 60 from coming off is disposed inside the retaining recess 61.

[0056] The outer peripheral surface of the resin portion 53 is the outer peripheral surface of the rotor 50. The outer peripheral surface of the resin portion 53 is located radially inwardly away from the inner peripheral surface of the rotor accommodating portion 12. The outer peripheral surface of the second covering portion 53a faces the inner peripheral surface of the rotor accommodating portion 12 with a small gap therebetween.

[0057] The pump portion 60 is connected to the lower side (one axial side) of the rotor 50. In this embodiment, the pump portion 60 is an impeller. The pump portion 60 is made of resin.

[0058] The pump section 60 has an impeller body section 62 that is connected to the lower end of the extension section 53b of the rotor 50. The resin section 53 and the impeller body section 62 are part of the same single member. The resin section including the resin section 53 and the impeller body section 62 is made, for example, by insert molding using the rotor assembly 55 as an insert member.

[0059] The impeller body 62 has a base plate portion 62a, a shroud plate portion 62b, a plurality of blade portions 62c, and a cylindrical portion 62d.

[0060] The base plate portion 62a and the shroud plate portion 62b are circular when viewed in the axial direction. The base plate portion 62a extends radially outward from the outer peripheral surface of the extension portion 53b. The shroud plate portion 62b extends radially outward below the base plate portion 62a along the plate surface of the base plate portion 62a.

[0061] The cylindrical portion 62d extends in the axial direction around the central axis J. The cylindrical portion 62d surrounds the extension portion 53b from the radially outer side. The interior of the cylindrical portion 62d is connected to the space between the base plate portion 62a and the shroud plate portion 62b. The blade portion 62c connects between the base plate portion 62a and the shroud plate portion 62b. The blade portion 62c extends in the radial direction. When the pump portion 60 rotates, the multiple blade portions 62c send the liquid between the blade portions 62c radially outward.

[0062] The pump section 60 has an intake port 64 that draws in water (liquid) and an outlet port 65 that discharges water (liquid). The intake port 64 faces downward and faces the inlet pipe 26 in the axial direction. On the other hand, the outlet port 65 faces radially outward and faces the outlet pipe 27 (see FIG. 1) in the radial direction.

[0063] The suction port 64 is provided at the lower end of the cylindrical portion 62d. The suction port 64 opens downward. On the other hand, the discharge port 65 is provided between the base plate portion 62a and the shroud plate portion 62b in the axial direction. The discharge port 65 opens radially outward. The pump portion 60 is rotated around the central axis J by the rotor 50, thereby drawing water into the interior through the suction port 64 and discharging it from the discharge port 65, thereby delivering the water. The water delivered by the pump portion 60 also flows into the inside of the rotor accommodating portion 12.

[0064] As shown in Fig. 3, the stator assembly 75 includes an annular stator core 71, a plurality of coils 73 attached to the stator core 71, a plurality of insulators 72 interposed between the stator core 71 and the plurality of coils 73, and a stator cover 90. 、 The stator core 71, the plurality of coils 73, and the plurality of insulators 72 constitute the stator 70. That is, the stator assembly 75 has the stator 70 and a stator cover 90.

[0065] The stator 70 is located radially outside the rotor 50 and surrounds the rotor 50. The stator 70 is annular and surrounds the rotor accommodating portion 12 and the rotor 50 radially outside the rotor accommodating portion 12. The stator 70 has a stator core 71, an insulator 72 attached to the stator core 71, and a plurality of coils 73 attached to the stator core 71 via the insulator 72.

[0066] The stator core 71 is located radially outside the rotor accommodating portion 12 and surrounds the rotor core 51. The stator core 71 has an annular core back 71a that surrounds the rotor core 51 and a plurality of teeth 71b that extend radially inward from the core back 71a. Although not shown in the figure, the plurality of teeth 71b are arranged side by side in the circumferential direction.

[0067] The radially inner ends of the multiple teeth 71b face, with a small gap between them, the outer circumferential surface of the cylindrical portion 12b in the rotor accommodating portion 12. That is, in this embodiment, the stator 70 is disposed in a state where it does not contact the outer circumferential surface of the cylindrical portion 12b.

[0068] As shown in Fig. 4, the coil 73 is formed by winding a coil wire 73a around the teeth 71b. An insulator 72 is interposed between the coil 73 and the teeth 71b. An end of the coil wire 73a extends upward from the coil 73. The extending coil wire 73a is connected to the circuit board 80. The number of coils 73 provided on the stator 70 is the same as the number of teeth 71b.

[0069] As shown in FIG. 3, the insulators 72 are attached to the teeth 71b. The insulators 72 cover the outer peripheral surfaces of the teeth 71b. The insulators 72 of this embodiment can be separated in the vertical direction. The insulators 72 are assembled to the teeth 71b from the vertical direction. The insulators 72 of this embodiment are attached to each tooth 71b. The number of insulators 72 provided on the stator 70 is the same as the number of teeth 71b.

[0070] The insulator 72 has an enclosing portion 72d disposed between the coil 73 and the tooth 71b, an outer wall portion 72b positioned radially outside the coil 73, and an inner wall portion 72c positioned radially inside the coil 73. The enclosing portion 72d is a square tube that covers the outer peripheral surface of the tooth 71b. The outer wall portion 72b and the inner wall portion 72c sandwich the coil 73 from both radial sides.

[0071] FIG. 7 is a perspective view of a stator assembly 75 of this embodiment. 3 and 7, a step portion 72a is provided on the outer surface of the outer wall portion 72b facing radially outward. The step portions 72a are provided on the upper and lower sides of the stator core 71. The step portions 72a are recessed radially inward from the outer surface of the outer wall portion 72b. The step portion 72a has a step surface facing the stator core 71.

[0072] As shown in Fig. 3, two step portions 72a are provided on one insulator 72. One of the two step portions 72a is located on the lower side of the stator core 71, and the other is located on the upper side of the stator core 71. As shown in Fig. 7, the multiple insulators 72 are lined up in the circumferential direction. Therefore, the multiple step portions 72a are lined up at equal intervals in the circumferential direction on the upper and lower sides of the stator core 71.

[0073] 3, the stator cover 90 covers the multiple coils 73. As described above, the coils 73 are disposed between the outer wall portion 72b and the inner wall portion 72c of the insulator 72. The coils 73 are exposed on both the upper and lower sides of the insulator 72. The stator cover 90 is disposed so as to straddle the space between the outer wall portion 72b and the inner wall portion 72c of the insulator 72.

[0074] The stator cover 90 has an annular first cover body 91 that covers the coil 73 from below (one axial side), and an annular second cover body 92 that covers the coil 73 from above (the other axial side).

[0075] According to this embodiment, the stator cover 90 covers the coil 73, thereby protecting the coil 73 from the molten resin material when the resin housing 30 is molded. Generally, an insulating coating is provided on the surface of the coil wire 73a. According to this embodiment, damage to the insulating coating of the coil wire 73a caused by the heat and injection pressure of the molten resin when the resin housing 30 is molded can be suppressed.

[0076] In this embodiment, a gap G is provided between the stator cover 90 and the coil 73. That is, according to this embodiment, an air layer is provided between the resin housing 30 and the coil 73, making it difficult for the heat of the molten resin during molding to be transmitted to the coil 73. This more reliably prevents damage to the insulating coating of the coil wire 73a.

[0077] Generally, the coil 73 is formed by winding the coil wire 73a, and therefore the outer shape of the coil 73 is not stable. According to this embodiment, by providing the gap G between the stator cover 90 and the coil 73, the stator cover 90 can be assembled to the stator 70 regardless of the shape of the coil 73.

[0078] The surface of the coil 73 has a complex, uneven shape because the outer shape of the coil wire 73a is exposed. Therefore, when the surface of the coil 73 is molded with the resin housing 30, it is difficult for the molten resin to flow into the gaps between the coil wires 73a, and sink marks are likely to occur inside the resin housing 30. Furthermore, because the surface of the coil 73 has a complex, uneven shape, it is difficult to control the thickness of the resin housing 30, resulting in a problem of difficulty in stabilizing dimensional accuracy.

[0079] According to this embodiment, the resin housing 30 covers the stator cover 90 without covering the surface of the coil 73. In other words, there is no need for the mold resin to cover the complex uneven shape, which can suppress sink marks in the resin housing 30 and stabilize dimensional accuracy.

[0080] According to this embodiment, when the resin housing 30 is molded, the molten resin material covers the surfaces of the stator cover 90 and the stator core 71. This seals off each part of the stator 70 from the outside. Furthermore, the stator cover 90 is firmly fixed to the stator core 71, which increases the reliability of the protection of the coils 73 by the stator cover 90.

[0081] According to this embodiment, the stator cover 90 includes a pair of cover bodies 91 and 92 that respectively cover the coils 73 from above and below. This allows the stator cover 90 to be easily assembled to the stator 70. Furthermore, the pair of cover bodies 91 and 92 of the stator cover 90 can effectively cover the exposed portions of the coils 73 from above and below.

[0082] 7, the first cover body 91 and the second cover body 92 each have an annular main body portion 93, an outer cylindrical portion 95, an inner cylindrical portion 96, a plurality of locking portions 94a, and a plurality of sealing wall portions 94f. The second cover body 92 also has a plurality of columnar portions 97 and a terminal holding portion 98. That is, the stator cover 90 has the annular main body portion 93, the outer cylindrical portion 95, the inner cylindrical portion 96, the locking portions 94a, the sealing wall portions 94f, the columnar portions 97, and the terminal holding portion 98.

[0083] The annular main body portion 93 is annular and centered on the central axis J. The annular main body portion 93 has a plurality of lightening holes 93a. The lightening holes 93a are open on the surface of the annular main body portion 93 facing away from the stator core 71. The annular main body portion 93 of the first cover body 91 is located below the coil 73, and the annular main body portion 93 of the second cover body 92 is located above the coil 73.

[0084] As shown in FIG. 4 , the outer cylinder portion 95 extends from the outer edge of the annular main body portion 93 toward the stator core 71. The outer cylinder portion 95 and the inner cylinder portion 96 are each cylindrical and centered on the central axis J. On the other hand, the inner cylinder portion 96 extends from the inner edge of the annular main body portion 93 toward the stator core 71. The outer cylinder portion 95 and the inner cylinder portion 96 of the first cover body 91 extend upward from the annular main body portion 93. The outer cylinder portion 95 and the inner cylinder portion 96 of the second cover body 92 extend downward from the annular main body portion 93. In the following description, the tip portion of the outer cylinder portion 95 or the inner cylinder portion 96 refers to the end portion on the stator core 71 side in the axial direction.

[0085] The inner cylindrical portion 96 overlaps the inner wall portion 72c of the insulator 72 when viewed in the axial direction. The tip end of the inner cylindrical portion 96 contacts the end surface of the inner wall portion 72c facing the axial direction. The inner cylindrical portion 96 is located radially inside the coil 73. The inner circumferential surface of the inner cylindrical portion 96 facing radially inward is continuous with the inner surface of the inner wall portion 72c facing radially inward. The inner circumferential surface of the inner cylindrical portion 96 and the inner surface of the inner wall portion 72c fit into the outer circumferential surface of the cylindrical portion 12b of the rotor accommodating portion 12.

[0086] According to this embodiment, the outer peripheral surface of the cylindrical portion 12b of the support member 10 fits into the inner cylindrical portion 96. The gap between the inner cylindrical portion 96 and the cylindrical portion 12b is small enough to prevent molten resin from passing through during molding. This prevents molten resin from flowing from the radially inner side of the inner cylindrical portion 96 into the coil 73 side (i.e., gap G) during molding of the resin housing 30. As a result, the coil 73 can be separated from the resin housing 30, thereby protecting the coil 73.

[0087] The outer cylinder portion 95 is disposed radially outside the outer wall portion 72b of the insulator 72. The outer cylinder portion 95 covers the vicinity of the upper end of the outer surface of the outer wall portion 72b from the radial outside. The tip end of the outer cylinder portion 95 faces the end face of the stator core 71 with a gap therebetween.

[0088] 3, the locking portion 94a extends from the tip end of the outer cylindrical portion 95 toward the stator core 71. The locking portion 94a of the first cover body 91 extends upward from the upper end of the outer cylindrical portion 95. The locking portion 94a of the second cover body 92 extends downward from the lower end of the outer cylindrical portion 95.

[0089] The locking portion 94a extends along the outer wall portion 72b of the insulator 72. A claw portion 94aa is provided at the tip of the locking portion 94a. The claw portion 94aa is locked to a step portion 72a provided on the outer surface of the outer wall portion 72b. In other words, the cover bodies 91, 92 have a plurality of claw portions 94aa that extend toward the stator core 71 and are locked to the insulator 72.

[0090] 7, the locking portions 94a are arranged at equal intervals along the circumferential direction. In this embodiment, the first cover body 91 and the second cover body 92 are each provided with the same number of locking portions 94a as the insulators 72. Each of the locking portions 94a is locked to one step portion 72a provided on the insulator 72.

[0091] According to this embodiment, the first cover body 91 and the second cover body 92 are assembled to the stator 70 from above and below. The locking portions 94a function as snap fits. Therefore, during the assembly process, the locking portions 94a elastically deform radially outward until the claw portions 94aa reach the stepped portions 72a. Reinforcing ribs 94ab are provided on the outer surfaces of the locking portions 94a. The reinforcing ribs 94ab reinforce the locking portions 94a while ensuring the elastic modulus of the locking portions 94a radially outward.

[0092] According to the present embodiment, the first cover body 91 and the second cover body 92 are engaged with and fixed to the stator 70. This makes it possible to prevent the first cover body 91 and the second cover body 92 from being misaligned with respect to the stator 70 when the resin housing 30 is molded. Furthermore, according to the present embodiment, the first cover body 91 and the second cover body 92 are fixed to the stator 70 by snap fitting, which simplifies the assembly process of the stator assembly 75.

[0093] The sealing wall portion 94f extends from the tip end of the outer cylindrical portion 95 toward the stator core 71. The sealing wall portion 94f of the first cover body 91 extends upward from the upper end of the outer cylindrical portion 95. The sealing wall portion 94f of the second cover body 92 extends downward from the lower end of the outer cylindrical portion 95.

[0094] The sealing wall portion 94f is plate-shaped with its thickness direction aligned in the radial direction. The sealing wall portion 94f is disposed between the locking portions 94a adjacent to each other in the circumferential direction. That is, the sealing wall portion 94f is disposed between the claw portions 94aa in the circumferential direction. As described above, the insulators 72 are arranged in the circumferential direction. The outer wall portion 72b of each insulator 72 extends in an arc shape along the circumferential direction when viewed from the axial direction. The outer wall portions 72b of the insulators 72 arranged in the circumferential direction are continuous in the circumferential direction. As a result, the outer wall portions 72b of the multiple insulators 72 form a cylindrical shape. The sealing wall portion 94f covers the gaps between the outer wall portions 72b of the insulators 72 arranged in the circumferential direction.

[0095] According to this embodiment, the sealing wall portion 94f covers the gap between circumferentially adjacent insulators 72 from the radially outer side. This makes it possible to prevent molten resin from flowing into the coil 73 side (i.e., gap G) from the gap between the insulators 72 when molding the resin housing 30. As a result, the coil 73 can be separated from the resin housing 30, and the coil 73 can be protected.

[0096] When the resin housing 30 is molded, the first cover body 91 and the second cover body 92 are pressed toward the stator core 71 by the resin pressure of the molten resin. The locking portions 94a of the first cover body 91 and the second cover body 92 have low strength to allow smooth elastic deformation when locked. In this embodiment, the tip surface of the sealing wall portion 94f facing the axial direction comes into contact with the stator core 71. Therefore, the sealing wall portion 94f receives a force resulting from the resin pressure applied to the first cover body 91 and the second cover body 92, thereby preventing damage to the locking portions 94a.

[0097] The columnar portions 97 extend upward from the upper surface of the annular main body portion 93 of the second cover body 92. Three columnar portions 97 are provided on the second cover body 92. The three columnar portions 97 are lined up in the circumferential direction. A through hole (coil holding portion) 97h opens on the upper surface of each columnar portion 97. That is, the through hole 97h is provided in the second cover body 92. In this embodiment, two through holes 97h open in one columnar portion 97.

[0098] 4, the through-hole 97h extends linearly in the axial direction. The through-hole 97h extends across the annular main body portion 93 and the columnar portion 97 in the second cover body 92.

[0099] The coil wire 73a extending upward from the coil 73 is inserted through the through hole 97h. The through hole 97h functions as a coil holding portion that holds the coil wire 73a. That is, the stator cover 90 has a coil holding portion (through hole 97h) that holds the coil wire.

[0100] In this embodiment, holding the coil wire 73a means supporting the coil wire 73a along the axial direction to maintain the posture and position of the coil wire 73a. The inner circumferential surface of the through hole 97h may be in close contact with the coil wire 73a. The diameter of the through hole 97h is preferably 1.5 times or less the wire diameter of the coil wire 73a.

[0101] In this embodiment, the coil holding portion that holds the coil 73 is the through hole 97h, which can surround the entire outer periphery of the coil wire 73a and stably hold the coil wire 73a. However, the coil holding portion may be a notch or the like recessed radially inward from the outer periphery of the second cover body 92.

[0102] The through hole 97h is provided with a tapered portion 97t whose cross-sectional area decreases toward the upper side (the other axial side). In this embodiment, the tapered portion 97t is located at the lower end of the through hole 97h. The cross-sectional shape of the through hole 97h is circular over its entire length, including the tapered portion 97t. According to this embodiment, when assembling the stator cover 90, it becomes easier to guide the end of the coil wire 73a into the through hole 97h, facilitating the assembly process of the stator assembly 75.

[0103] In this embodiment, the stator cover 90 holds the coil wire 73a that is drawn out from the coil 73 through the through-hole 97h and connected to the circuit board 80. This allows the stator cover 90 to position the coil wire 73a, facilitating the process of connecting the coil wire 73a to the circuit board 80.

[0104] In this embodiment, the through hole 97h connects the space inside the case 2 that houses the coil 73 and the space that houses the circuit board 80. Therefore, when the resin housing 30 is molded, the molten resin does not come into contact with the coil wire 73a drawn from the coil 73. That is, the stator cover 90 can protect the drawn coil wire 73a from the molten resin at the through hole 97h.

[0105] The through hole 97h in this embodiment overlaps with the first through hole 81h of the circuit board 80 when viewed in the axial direction. Therefore, the coil wire 73a extending upward from the through hole 97h can be smoothly inserted into the first through hole 81h of the circuit board 80. Furthermore, because the coil wire 73a is held by the through hole 97h, the coil wire 73a can be stably soldered to the first through hole 81h, thereby improving the reliability of the connection between the coil wire 73a and the circuit board 80.

[0106] The through hole 97h in this embodiment extends in the axial direction inside the columnar portion 97. The columnar portion 97 also extends along the axial direction and penetrates the resin housing 30 in the axial direction. This allows the through hole 97h to be long, which increases the reliability with which the coil wire 73a is held by the through hole 97h.

[0107] An upper end surface (tip surface) 97a of the columnar portion 97 is exposed above the resin housing 30. When the resin housing 30 is molded, the upper end surface 97a is covered by a mold. The upper end surface 97a of the columnar portion 97 faces the circuit board 80, and is provided with an opening for the through hole 97h. Therefore, when the resin housing 30 is molded, molten resin does not enter the inside of the through hole 97h, and the coil wire 73a can be more reliably protected.

[0108] As shown in Fig. 7, the terminal holding portion 98 is disposed on the upper surface of the annular main body portion 93 of the second cover body 92. The terminal holding portion 98 has a radially extending portion 98a extending radially outward relative to the second cover body 92, and an upper protrusion 98b extending upward from the radially outer end of the radially extending portion 98a. The terminal holding portion 98 holds multiple (three in this embodiment) terminals 8 embedded therein. The second cover body 92 is formed by insert molding, in which the terminals 8 are inserted.

[0109] The terminal 8 has a base 8c extending radially, a first end 8a extending upward from the radially inner end of the base 8c, and a second end 8b extending upward from the radially outer end of the base 8c. The base 8c extends radially within the radially extending portion 98a of the terminal holding portion 98. The first end 8a protrudes upward from the radially extending portion 98a. The second end 8b extends upward along the upper protrusion 98b and protrudes upward from the upper end surface of the upper protrusion 98b.

[0110] 2, a first end 8a of the terminal 8 passes through the interior of the resin housing 30 and protrudes upward from the housing top surface 30g. The first end 8a is inserted into a second through-hole 81k of the circuit board 80 and connected to the circuit board 80 by soldering.

[0111] A second end 8b of the terminal 8 protrudes upward from a connector portion 39 of the resin housing 30. The connector portion 39 surrounds the second end 8b of the terminal 8, exposing it. The second end 8b is connected to an external device 7 that is connected to the connector portion 39. The external device 7 supplies power to the circuit board 80 via the terminal 8. The circuit board 80 also supplies power to the coil 73 from the coil wire 73a.

[0112] According to this embodiment, the stator cover 90 has the terminal holding portion 98, so that the terminals 8 can be held in advance in the stator cover 90. Therefore, when the resin housing 30 is molded, the terminals 8 can be easily embedded inside the resin housing 30, which simplifies the manufacturing process.

[0113] The pump cover 20 forms the lower end of the case 2. The pump cover 20 is located below (on one axial side of) the motor 3, the resin housing 30, and the support member 10. The pump cover 20 covers the pump section 60. The pump cover 20 has a pump surrounding section 22, an upper cylindrical section 21, an inlet pipe 26, and an outlet pipe 27 (see FIG. 1). The pump surrounding section 22 covers the pump section 60 from the radially outer side and from below.

[0114] A flow path through which water (liquid) flows is provided inside the pump surrounding portion 22. The upper cylindrical portion 21 extends upward from the upper end of the pump surrounding portion 22. The upper cylindrical portion 21 is cylindrical and has a center on the central axis J. The upper cylindrical portion 21 surrounds the outer peripheral surface of the holding cylindrical portion 31 of the resin housing 30.

[0115] 1, the inlet pipe 26 extends downward from the lower end of the pump enclosure 22. The outlet pipe 27 extends radially outward from the outer periphery of the pump enclosure 22. The inlet pipe 26 and the outlet pipe 27 are connected to the internal space of the pump enclosure 22.

[0116] The pump cover 20 is joined to the resin housing 30 and the support member 10 by welding. The joining configuration between the pump cover 20, the resin housing 30, and the support member 10 will be described below. The pump cover 20 is welded to the resin housing 30 and the support member 10 by spin welding.

[0117] As shown in FIG. 6, the pump cover 20 has an annular first contact surface 20f. The first contact surface 20f has a main region 20a facing upward (the other axial side) and a sub-region 20b facing radially inward. The main region 20a is the upper end surface of the pump enclosing portion 22. The sub-region 20b is located on the inner circumferential surface of the upper end cylindrical portion 21. The main region 20a and the sub-region 20b are connected to each other perpendicularly. Both the main region 20a and the sub-region 20b extend annularly in the circumferential direction around the central axis J.

[0118] The resin housing 30 has a second contact surface 30f and a fourth contact surface 30e at its lower end. The second contact surface 30f is a flat surface facing downward (the other axial side). On the other hand, the fourth contact surface 30e is a curved surface facing radially outward. The second contact surface 30f and the fourth contact surface 30e extend annularly in the circumferential direction around the central axis J. The second contact surface 30f is the lower end surface of the retaining cylindrical portion 31. On the other hand, the fourth contact surface 30e is located on the outer circumferential surface of the retaining cylindrical portion 31. In other words, the second contact surface 30f and the fourth contact surface 30e are provided on the retaining cylindrical portion 31. The second contact surface 30f is in contact with and welded to the main region 20a of the first contact surface 20f in the up-down direction. On the other hand, the fourth contact surface 30e is in contact with and welded to the sub-region 20b of the first contact surface 20f in the radial direction.

[0119] The support member 10 has a third contact surface 10f at its lower end. The third contact surface 10f is a flat surface facing downward (the other axial side). The third contact surface 10f extends annularly in the circumferential direction around the central axis J. The third contact surface 10f is the lower end surface of the flange portion 11. In other words, the third contact surface 10f is provided on the flange portion 11. The third contact surface 10f is located at a position slightly larger than the first contact surface 20f in the vertical direction. Main area 20a The third contact surface 10f is disposed adjacent to and radially inward of the second contact surface 30f. The second contact surface 30f and the third contact surface 10f are disposed on the same plane perpendicular to the central axis J.

[0120] According to this embodiment, the first contact surface 20f of the pump cover 20 is welded to the second contact surface 30f of the resin housing 30 and the third contact surface 10f of the support member 10. Welding the first contact surface 20f to the second contact surface 30f seals the waterproof region A1 and the flow path region A2 inside the case 2 from the outside of the case 2. Welding the first contact surface 20f to the third contact surface 10f seals the waterproof region A1 and the flow path region A2 from each other inside the case 2. This allows the pump 1 to be sealed without using a sealing member such as an O-ring, reduces the number of parts, and enables the production of an inexpensive and highly reliable pump 1.

[0121] Additionally, according to this embodiment, the resin housing 30 and the support member 10 are welded to one contact surface (first contact surface 20f) of the pump cover 20. This makes it possible to join the two members, the resin housing 30 and the support member 10, to the pump cover 20 in a single welding process, thereby simplifying the welding process.

[0122] According to this embodiment, since the first contact surface 20f is annular, the welded portion can be arranged annularly, and the inner and outer regions of the welded portion can be sealed from each other. In addition, since the first contact surface 20f is annular, it is possible to employ spin welding, in which the pump cover 20 is rotated relative to the resin housing 30 and the support member 10 to weld the contact surfaces together, thereby improving the work efficiency of the welding process.

[0123] In this embodiment, the pump cover 20, the resin housing 30, and the support member 10 are joined by spin welding, but other welding means may be used. For example, the pump cover 20, the resin housing 30, and the support member 10 may be welded by ultrasonic welding, laser welding, or the like.

[0124] According to this embodiment, the first contact surface 20f faces upward, and the second contact surface 30f and the third contact surface 10f welded to the first contact surface 20f face downward. This allows welding to be performed while applying axial stress to the contact portions between the first contact surface 20f and the second contact surface 30f and the third contact surface 10f, thereby improving the welding efficiency when spin welding is employed.

[0125] As described above, the support member 10 is molded with the resin housing 30. Therefore, the support member 10 and the resin housing 30 are in close contact with each other but are not joined together. Therefore, a small gap is provided between the support member 10 and the resin housing 30.

[0126] In this embodiment, the second contact surface 30f of the resin housing 30 and the third contact surface 10f of the support member 10 are disposed adjacent to each other in the radial direction. Therefore, part of the resin material melted in the welding process enters the minute gap between the support member 10 and the resin housing 30 and solidifies. This enables sealing between the support member 10 and the resin housing 30, achieving a more reliable sealing structure.

[0127] 1, the protrusion 11e provided on the outer peripheral surface of the flange portion 11 fits into the recess 31e of the holding cylinder portion 31. According to this embodiment, the protrusion 11e and the recess 31e function as a rotation stopper between the support member 10 and the resin housing 30. This makes it possible to prevent the resin housing 30 and the support member 10 from rotating relative to each other during the welding process using spin welding.

[0128] According to this embodiment, the protrusions 11e and recesses 31e are aligned along the circumferential direction and fit together. Therefore, the minute gap between the support member 10 and the resin housing 30 extends in a wavy pattern along the circumferential direction. The resin material melted by spin welding spreads in the circumferential direction at the interfaces between the first contact surface 20f, the second contact surface 30f, and the third contact surface 10f due to the rotation during spin welding. According to this embodiment, by arranging the gap between the support member 10 and the resin housing 30 in a wavy pattern along the circumferential direction, the resin material melted during spin welding can effectively penetrate into the gap and solidify, thereby achieving a highly reliable sealing structure.

[0129] As shown in FIG. 6, the pump cover 20 of this embodiment has a sub-region 20b of the first contact surface 20f. 4th contact surface 30e According to this embodiment, a wide welding surface area can be secured, further improving the reliability of sealing. In addition, the welding surface can have an intricate labyrinth structure, which increases the reliability of sealing and the rigidity of the welded portion.

[0130] In this embodiment, the pump cover 20 has an upper end surface 21a located at the upper end of the upper cylindrical portion 21. The upper end surface 21a is an annular flat surface facing upward (the other axial direction). A step portion 30d that is recessed downward and radially inward is provided at the lower end of the outer circumferential surface 30a of the resin housing 30. The upper cylindrical portion 21 of the pump cover 20 is fitted into the step portion 30d.

[0131] The step portion 30d has an opposing surface 32b facing downward. That is, the resin housing 30 has the opposing surface 32b. The opposing surface 32b faces the upper end surface 21a of the upper end tubular portion 21 across a gap. According to this embodiment, by providing a gap between the opposing surface 32b and the upper end surface 21a, even if parts of the first contact surface 20f and the second contact surface 30f melt during the welding process and the pump cover 20 and the resin housing 30 become relatively closer in the axial direction, interference between the opposing surface 32b and the upper end surface 21a can be suppressed.

[0132] In this embodiment, the resin housing 30, pump cover 20, and support member 10, which are welded together, are preferably made of the same type of resin material. Similarly, the resin housing 30 and board cover 28, which are welded together, are preferably made of the same type of resin material. By making the welded members out of the same type of resin material, strong welding can be achieved, and thermal distortion is less likely to occur after welding, preventing damage to the welded portion.

[0133] Although various embodiments of the present invention have been described above, the configurations and combinations thereof in each embodiment are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

[0134] For example, the use of a pump to which the present invention is applied is not particularly limited. The pump may be mounted on any type of equipment. The pump may be mounted on a vehicle, for example. The pump may be a pump that pumps any type of fluid. The pump may be an oil pump that pumps oil. Note that the configurations described above in this specification can be combined as appropriate within a range that does not contradict each other. [Explanation of symbols]

[0135] DESCRIPTION OF SYMBOLS 1...pump, 3...motor, 7...external device, 8...terminal, 8a...first end, 8b...second end, 9, 109...thermal conductive material, 10...support member, 10f...third contact surface, 11...flange portion, 11d...positioning rib, 11e...protrusion, 12...rotor accommodating portion, 12a...lid portion, 12b...cylindrical portion, 12c...retaining portion, 20...pump cover, 20a...main region, 20b...sub-region, 20f...first contact surface, 30...resin housing (motor housing), 30a...outer circumferential surface, 30e...fourth contact surface, 30f...second contact surface, 31...retaining cylindrical portion, 31e...recess, 32a...step surface, 32b...opposing surface, 39...connector portion, 40...fixed shaft, 41...shaft main body portion, 42...retaining member, 42a ...exposed portion, 42f...holding member flange portion (flange portion), 50...rotor, 60...pump portion, 64...suction port, 65...discharge port, 70...stator, 71...stator core, 72...insulator, 73...coil, 73a...coil wire, 75...stator assembly, 80...circuit board, 81...board body, 81h...first through hole (through hole), 82...heat generating element, 90...stator cover, 91...first cover body (cover body), 92...second cover body (cover body), 94aa...claw portion, 94f...sealing wall portion, 96...inner cylinder portion, 97...columnar portion, 97a...upper end surface (tip surface), 97h...through hole (coil holding portion), 97t...tapered portion, 98...terminal holding portion, G...gap, J...central axis

Claims

1. a rotor rotatable about a central axis; a stator assembly positioned radially outside the rotor and surrounding the rotor; a pump portion connected to one axial side of the rotor; a support member positioned radially inside the stator assembly and having a rotor accommodating portion that accommodates the rotor therein; a resin housing that molds the stator assembly and the support member, The rotor accommodating portion is a cover portion that covers the rotor from the other axial side; a cylindrical portion located between the rotor and the stator assembly in the radial direction and opening to one axial side, The stator assembly is an annular stator core; a plurality of coils attached to the stator core; a stator cover that covers the plurality of coils; a plurality of insulators interposed between the stator core and the plurality of coils, the stator cover includes a pair of annular cover bodies that respectively cover the coil from one axial side and the other axial side, the cover body has a plurality of claws extending toward the stator core and latched to the insulator, the cover body has a sealing wall portion disposed between the claw portions in the circumferential direction, the stator assembly has the plurality of insulators arranged in a circumferential direction, The sealing wall portion covers a space between the insulators adjacent in the circumferential direction from the radially outer side. pump.

2. An axially facing tip end surface of the sealing wall portion contacts the stator core.

2. The pump of claim 1.

3. The cover body has an inner cylindrical portion located radially inside the coil and into which an outer peripheral surface of the cylindrical portion fits.

3. A pump according to claim 1 or 2.

4. A gap is provided between the stator cover and the coil. A pump according to any one of claims 1 to 3.

5. a rotor rotatable about a central axis; a stator assembly positioned radially outside the rotor and surrounding the rotor; a pump portion connected to one axial side of the rotor; a support member positioned radially inside the stator assembly and having a rotor accommodating portion that accommodates the rotor therein; a resin housing that molds the stator assembly and the support member, The rotor accommodating portion is a cover portion that covers the rotor from the other axial side; a cylindrical portion located between the rotor and the stator assembly in the radial direction and opening to one axial side, The stator assembly is an annular stator core; a plurality of coils attached to the stator core; a stator cover that covers the plurality of coils; a plurality of insulators interposed between the stator core and the plurality of coils, the stator cover includes a pair of annular cover bodies that respectively cover the coil from one axial side and the other axial side, the cover body has a plurality of claws extending toward the stator core and latched to the insulator, The cover body is an annular main body portion that overlaps the coil in the axial direction; a cylindrical outer cylinder portion extending from an outer edge of the annular main body portion toward the stator core; a cylindrical inner tube portion extending from an inner edge of the annular main body portion toward the stator core and positioned radially inside the coil; a plurality of locking portions extending from a tip end portion of the outer cylindrical portion on the stator core side toward the stator core; a plurality of sealing wall portions extending from a tip end portion of the outer cylinder portion on the stator core side toward the stator core, the stator assembly has the plurality of insulators arranged in a circumferential direction, The locking portion has the claw portion, the sealing wall portion is disposed between the claw portions in the circumferential direction and covers a space between the insulators adjacent in the circumferential direction from the radially outer side; pump.

Images