Pump

Abstract

One embodiment of a pump according to the present disclosure comprises a rotor, a stator, a pump part, and a housing. The housing has a partition part that partitions an internal space. The partition part has a lid part that covers the rotor from the other side in the axial direction, a first cylindrical part that has a cylindrical shape centered on a central axis and that is positioned between the rotor and the stator in the radial direction, and a bottom part that spreads outward in the radial direction from the end on one side in the axial direction of the first cylindrical part and that is positioned between the pump part and the stator in the axial direction. The bottom part has a first surface facing the stator in the axial direction, and a second surface facing the pump part in the axial direction. The first surface is provided with a first rib extending in the radial direction between coils that are adjacent in the circumferential direction. The second surface is provided with a groove that overlaps the first rib and extends in the radial direction when viewed from the axial direction.

Description

pump

[0001] The present invention relates to a pump.

[0002] A pump equipped with a motor and an impeller requires a waterproof structure that prevents fluid from entering the stator. Patent Document 1 discloses a structure in which the stator is insert-molded to isolate the stator from the fluid.

[0003] Japanese Patent Application Laid-Open No. 2021-195921

[0004] However, when the stator is insert molded, not only is heat radiation from the stator likely to be insufficient, but the weight of the resin portion also increases, resulting in an overall increase in weight.

[0005] In view of the above circumstances, one object of the present invention is to provide a pump that is lightweight and has an improved cooling efficiency for the stator.

[0006] One aspect of the pump of the present invention includes a rotor rotatable about a central axis, a stator positioned radially outward of the rotor and surrounding the rotor, a pump section connected to one axial side of the rotor, and a housing accommodating the rotor, the stator, and the pump section. The stator includes an annular core back centered on the central axis, a stator core having a plurality of teeth extending radially inward from the core back and arranged circumferentially, and a plurality of coils attached to the teeth. The housing has a partition portion that divides an internal space into a first accommodating chamber that accommodates the rotor and the pump section and a second accommodating chamber that accommodates the stator. The partition portion includes a lid portion that covers the rotor from the other axial side, a cylindrical first cylindrical portion centered on the central axis and positioned radially between the rotor and the stator, and a bottom portion that extends radially outward from one axial end of the first cylindrical portion and is positioned axially between the pump section and the stator. The bottom portion has a first surface facing the stator in the axial direction and a second surface facing the pump portion in the axial direction. The first surface is provided with a first rib extending radially between adjacent coils in the circumferential direction. The second surface is provided with a groove extending radially and overlapping the first rib when viewed from the axial direction.

[0007] According to one aspect of the present invention, it is possible to provide a pump that is lightweight and has an improved stator cooling efficiency.

[0008] FIG. 1 is a perspective view of a pump according to an embodiment. FIG. 2 is a cross-sectional view of the pump according to an embodiment. FIG. 3 is a cross-sectional view of a stator and a partition according to an embodiment taken along line III-III in FIG. 2. FIG. 4 is a perspective view of a stator and a substrate according to an embodiment. FIG. 5 is a schematic diagram showing a circuit formed by coil wire according to an embodiment. FIG. 6 is a schematic diagram showing a connection configuration of nine coils according to an embodiment. FIG. 7 is a cross-sectional view of a breather according to an embodiment. FIG. 8 is a perspective view of a can according to an embodiment as seen from above. FIG. 9 is a perspective view of a can according to an embodiment as seen from below. FIG. 10 is a perspective view of a heat sink according to an embodiment as seen from above. FIG. 11 is a perspective view of a heat sink according to an embodiment as seen from below. FIG. 12 is a cross-sectional perspective view showing an enlarged view of an annular groove and a first cylindrical portion in a partition according to an embodiment. FIG. 13 is a cross-sectional perspective view showing a portion of an outer edge of a heat sink according to an embodiment.

[0009] Each figure shows an imaginary central axis J of a pump 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 about the central axis J will be simply referred to as the "radial direction," and the circumferential direction about 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 the following embodiments, the lower side (-Z) corresponds to “one axial side,” and the upper side (+Z) corresponds to “the other axial side.” Note that the terms “upper side” and “lower side” are simply names used to describe the relative positional relationships of the various components, and the actual positional relationships may be other than those indicated by these names.

[0011] <Pump> Fig. 1 is a perspective view of a pump 100 of this embodiment. The pump 100 of this embodiment is an electric pump. The pump 100 draws in a fluid to be pumped through an inlet 54d and discharges it through a discharge outlet 54e. The fluid to be pumped by the pump 100 of this embodiment is water. In other words, the pump 100 of this embodiment is a water pump. The pump of this embodiment may also be a pump that pumps a fluid other than water. The use of the pump is not particularly limited.

[0012] Fig. 2 is a cross-sectional view of the pump 100 of this embodiment taken along the central axis J. As shown in Fig. 2, the pump 100 includes a rotor 10, a stator 20, a fixed shaft 2, a pump section 40, a substrate 70, and a housing 50. The rotor 10 and the stator 20 form a motor.

[0013] <Rotor> The rotor 10 is rotatable about a central axis J. The rotor 10 includes a rotor core 11, a plurality of magnets 12, a resin portion 13, and a bearing member 15.

[0014] The rotor core 11 is annular and surrounds the central axis J. The magnet 12 is fixed to a radially outer surface of the rotor core 11. The magnets 12 are spaced apart in the circumferential direction. The resin portion 13 is generally cylindrical and surrounds the central axis J, extending in the axial direction. The rotor core 11 and the magnets 12 are supported by the resin portion 13. In the rotor 10 of this embodiment, the magnet 12 is located radially outside the rotor core 11. That is, the motor of the pump 100 of this embodiment is an SPM motor (Surface Permanent Magnet Motor). However, the magnet 12 may be located radially inside the rotor core 11. That is, the motor of the pump 100 may be an IPM motor (Interior Permanent Magnet Motor).

[0015] The bearing member 15 has a generally cylindrical shape that surrounds the central axis J and extends in the axial direction. The bearing member 15 is located radially inside the resin portion 13. The outer peripheral surface of the bearing member 15 is fixed to the inner peripheral surface of the resin portion 13. The bearing member 15 is made of, for example, resin. The bearing member 15 of this embodiment is a so-called sliding bearing.

[0016] <Stator> As shown in Fig. 2, the stator 20 is located radially outside the rotor 10. The stator 20 surrounds the rotor 10. The stator 20 includes a stator core 21, an insulator (terminal support member) 30, a plurality of coils 23, and terminal members 3 (see Fig. 4).

[0017] 2, the stator core 21 is located radially outside the rotor core 11 and the plurality of magnets 12 and surrounds the rotor core 11 and the plurality of magnets 12. The stator core 21 is located radially outside a first cylindrical portion 63, which will be described later.

[0018] Fig. 3 is a cross-sectional view of the stator 20 and a part (partition portion 60) of the housing 50 of this embodiment taken along line III-III in Fig. 2. As shown in Fig. 3, the stator core 21 has a core back 24 and a plurality of teeth 25.

[0019] The core back 24 has an annular shape surrounding the central axis J. In this embodiment, the core back 24 has a substantially circular annular shape centered on the central axis J. The core back 24 surrounds a first cylindrical portion 63 (described later) from the radial outside.

[0020] The teeth 25 extend radially inward from the core back 24. The teeth 25 are arranged at equal intervals in the circumferential direction. Nine teeth 25 are provided in the stator core 21 of this embodiment. Each tooth 25 has a tooth main body portion 25a and an umbrella portion 25b. The tooth main body portion 25a extends radially inward from the radially inner surface of the core back 24. The umbrella portion 25b is connected to the radially inner end of the tooth main body portion 25a. The umbrella portion 25b protrudes on both circumferential sides from the tooth main body portion 25a. When viewed in the axial direction, the radially inner surface of the umbrella portion 25b is arc-shaped with the central axis J as its center. The radially inner surface of the umbrella portion 25b is the radially inner surface of the tooth 25.

[0021] 2 , the insulator 30 is attached to the stator core 21. The insulator 30 has a plurality of tooth cover portions 35, a first outer protrusion 31, a second outer protrusion 32, a plurality of first inner protrusions 33, and a plurality of second inner protrusions 34.

[0022] The plurality of tooth cover portions 35 are attached to the plurality of teeth 25. Each tooth cover portion 35 covers each tooth 25 from both axial and circumferential sides.

[0023] The first outer protrusion 31 and the second outer protrusion 32 are each annular and centered on the central axis J. The first outer protrusion 31 and the second outer protrusion 32 are connected to the radially outer ends of the plurality of tooth cover portions 35. The first outer protrusion 31 protrudes upward relative to the tooth cover portions 35. The second outer protrusion 32 protrudes downward relative to the tooth cover portions 35.

[0024] The first inner protrusion 33 is connected to the radially inner end of the tooth cover portion 35. The first inner protrusion 33 protrudes upward relative to the tooth cover portion 35. The second inner protrusion 34 is connected to the radially inner end of the tooth cover portion 35. The second inner protrusion 34 protrudes downward relative to the tooth cover portion 35.

[0025] Fig. 4 is a perspective view of the stator 20 and the substrate 70 of this embodiment. As shown in Fig. 4, the first outer protrusion 31 is located above the upper end surface of the core back 24. The first outer protrusion 31 has a circular annular wall portion 31a and a plurality of terminal support portions 36 that protrude upward from the upper end surface of the annular wall portion 31a.

[0026] The annular wall portion 31a has a guide surface 31f facing radially outward. The guide surface 31f is a cylindrical surface centered on the central axis J. The guide surface 31f guides the coil wire 23a extending in the circumferential direction from the radially inner side.

[0027] The terminal support portions 36 are each cylindrical and extend in the axial direction. When viewed in the axial direction, the terminal support portions 36 are rectangular, with the longitudinal direction perpendicular to the radial direction. The insulator 30 of this embodiment is provided with three terminal support portions 36. Each terminal support portion 36 supports a terminal member 3 from below. That is, the stator 20 of this embodiment has three terminal members 3. Note that in other embodiments, the stator 20 may have four or more terminal members 3. For example, the stator 20 may have four terminal members 3 or six terminal members 3.

[0028] The terminal support portion 36 is provided with a notch 36b and a recess 36a. The notch 36b extends downward (-Z direction) from the upper end surface of the terminal support portion 36. The notch 36b also extends in a groove-like manner in the radial direction. The recess 36a opens at the upper end surface of the terminal support portion 36 and is recessed downward. In this embodiment, the recess 36a is rectangular in shape with its longitudinal direction perpendicular to the radial direction when viewed from above. When viewed from the axial direction, the notch 36b and the recess 36a intersect with each other. When viewed from the axial direction, the notch 36b is also discontinued at the portion where it overlaps with the recess 36a.

[0029] The terminal member 3 is disposed in the recess 36a. The coil wire 23a is disposed inside the cutout 36b. The coil wire 23a is guided from the radially outer side to the radially inner side of the terminal support portion 36. As a result, the coil wire 23a extends in the radial direction so as to straddle the recess 36a. Note that when the coil wire 23a is passed through the cutout 36b, the coil wire 23a may be guided from the radially inner side to the radially outer side.

[0030] The terminal member 3 is plate-shaped and extends along a plane perpendicular to the radial direction. The terminal member 3 has a coil wire connection portion 3 b and a terminal pin 3 a located above the coil wire connection portion 3 b. The terminal member 3 is connected to the coil wire 23 a at the coil wire connection portion 3 b and to the substrate 70 at the terminal pin 3 a.

[0031] The terminal pins 3a are pin-shaped and extend upward. The terminal pins 3a are so-called press-fit pins. The terminal pins 3a are provided with holes penetrating in the radial direction. The provision of the holes penetrating in the radial direction allows the terminal pins 3a to elastically deform in the circumferential direction. The terminal pins 3a are elastically deformed when pressed from below by the through-holes 71h of the substrate 70. Due to the restoring force of the terminal pins 3a, each terminal pin 3a is fixed in the through-holes 71h and electrically connected to the substrate 70.

[0032] According to this embodiment, in the process of connecting the terminal member 3 and the substrate 70, the terminal pin 3a of the terminal member 3 is press-fitted into the through hole 71h of the substrate 70, thereby easily connecting the terminal member 3 and the substrate 70. That is, according to this embodiment, the process of connecting the terminal member 3 and the substrate 70 can be simplified, and an increase in the number of steps for assembling the pump 100 can be suppressed.

[0033] The coil wire connection portion 3b has a terminal notch 3c extending upward from its lower end. The terminal notch 3c opens downward (i.e., toward the other axial direction) at the lower end of the coil wire connection portion 3b. The terminal notch 3c sandwiches the coil wire 23a. The distance between opposing edges of the terminal notch 3c is smaller than the wire diameter of the coil wire 23a. The coil wire 23a is press-fitted into the terminal notch 3c, thereby coming into contact with the terminal notch 3c and connecting to the terminal member 3. The terminal member 3 is also sometimes called an insulation displacement connector or an IDC (Insulation-Displacement Connector) terminal.

[0034] The worker or device assembling pump 100 (hereinafter simply referred to as the worker) first inserts coil wire 23a into notch 36b of terminal support portion 36. Next, the worker inserts terminal member 3 into recess 36a of terminal support portion 36. Accordingly, coil wire 23a is inserted into terminal notch 3c of terminal member 3, and coil wire 23a and terminal member 3 are electrically connected.

[0035] In this embodiment, the terminal member 3 is supported from below by the insulator 30. That is, the insulator 30 in this embodiment functions as a terminal support member that supports the terminal member 3. Therefore, there is no need to provide a separate member for supporting the terminal member 3, and the number of parts constituting the pump 100 can be reduced.

[0036] 2 , the multiple coils 23 are attached to the teeth 25 via the tooth cover portions 35 of the insulators 30. That is, at least a portion of the insulators 30 is provided between the coils 23 and the teeth 25. Each coil 23 is formed by winding a conducting wire around the tooth cover portion 35.

[0037] FIG. 5 is a schematic diagram showing a circuit formed by the coil wire 23a of this embodiment. The stator 20 of this embodiment has nine coils 23. The nine coils 23 are classified into three U-phase coils 23U, three V-phase coils 23V, and three W-phase coils 23W. The nine coils 23 of this embodiment are connected by a delta connection. AC currents of the same phase flow through the coils 23 of the same phase. Furthermore, AC currents flowing through the coils 23 of different phases are shifted in phase by 120°. Note that the number of coils 23 of each phase is not limited to that of this embodiment.

[0038] As shown in Figure 5, all of the coils 23 in this embodiment are formed from a single coil wire 23a. In the following description, the portions of the coil wire 23a that connect the coils 23 together are referred to as crossover wires 23b and 23c. Of the crossover wires 23b and 23c, the portion that connects the coils 23 of the same phase in series is referred to as an in-phase crossover wire 23b, and the portion that connects the coils 23 of different phases is referred to as a connecting crossover wire 23c. In this embodiment, a terminal member 3 is connected to the connecting crossover wire 23c.

[0039] In this embodiment, both ends of the coil wire 23a are located on a connecting jumper wire 23c located between the V-phase coil 23V and the W-phase coil 23W. The both ends of the coil wire 23a are connected to each other via terminal members 3. This connects the coil wire 23a in a loop. Terminal members 3 are also connected to the connecting jumper wires 23c located between the U-phase coil 23U and the W-phase coil 23W, and between the U-phase coil 23U and the V-phase coil 23V.

[0040] Figure 6 is a schematic diagram showing the connection configuration of nine coils 23 in this embodiment. In Figure 6, one U-phase coil 23U is designated as the first coil, and coils 23 are numbered sequentially from this coil to the ninth coil in the circumferential direction. The multiple coils 23 are arranged in the circumferential direction in the order of U-phase coil 23U, V-phase coil 23V, and W-phase coil 23W. In Figure 6, the portions of crossover wires 23b, 23c that pass radially outside annular wall portion 31a of insulator 30 are shown with solid lines, and the portions that are arranged radially inside annular wall portion 31a are shown with dashed lines.

[0041] The plurality of in-phase crossover wires 23b each extend circumferentially radially outside the annular wall portion 31a. The plurality of connecting crossover wires 23c are connected to the terminal members 3 between the coils 23 of different phases. Each of the plurality of connecting crossover wires 23c has a portion that extends circumferentially radially outside the annular wall portion 31a between the coil 23 and the terminal member 3.

[0042] Four levels are provided radially outside the annular wall portion 31a at different positions in the axial direction. The multiple crossover wires 23b, 23c pass through one of the four levels at the portion extending circumferentially around the radially outside of the annular wall portion 31a. This prevents the multiple crossover wires 23b, 23c from shorting out with each other radially outside the annular wall portion 31a.

[0043] In this embodiment, one of the three connecting jumper wires 23c has an intersection 9 that radially intersects with the in-phase connecting wire 23b in the path from one coil 23 to the terminal member 3. The intersection 9 in this embodiment is provided on the connecting jumper wire 23c that connects the U-phase coil 23U and the V-phase coil 23V.

[0044] As shown in FIG. 4 , the annular wall portion 31a is provided with a wall notch 37, a first protrusion 38, and a second protrusion 39. The wall notch 37 extends downward from the upper end of the annular wall portion 31a. The wall notch 37 also penetrates the annular wall portion 31a in the radial direction. The first protrusion 38 and the second protrusion 39 are each arranged adjacent to the wall notch 37 in the circumferential direction. The first protrusion 38 is arranged on one circumferential side of the wall notch 37, and the second protrusion 39 is arranged on the other circumferential side of the wall notch 37. The first protrusion 38 is adjacent to the lower end of the wall notch 37, and the second protrusion 39 is adjacent to the upper end of the wall notch 37. Therefore, the first protrusion 38 and the second protrusion 39 are arranged offset in the axial direction. The first protrusion 38 protrudes radially outward from the guide surface 31f. The second projection 39 projects upward from the upper end surface of the annular wall portion 31a.

[0045] The connecting crossover wire 23c passes through the wall cutout 37 at the intersection 9 and is routed from the radially outer side to the radially inner side of the annular wall portion 31a. The connecting crossover wire 23c is hooked under the first protrusion 38 on one circumferential side of the intersection 9. This makes it possible to prevent the portion on one circumferential side of the intersection 9 from moving upward. Furthermore, the connecting crossover wire 23c is hooked radially inside the second protrusion 39 on the other circumferential side of the intersection 9, so that the connecting crossover wire 23c can be reliably guided radially inward at the intersection 9. According to this embodiment, the connecting crossover wire 23c can be guided radially inward while preventing contact of the connecting crossover wire 23c with the in-phase crossover wire 23b at the intersection 9.

[0046] In addition, according to this embodiment, by arranging a parting line on the surface of the first protrusion 38, it is possible to mold the annular wall portion 31 a using a mold that separates in the vertical direction, without using a mold with a complex structure such as a slide mold. Therefore, according to this embodiment, it is possible to reduce the manufacturing cost of the insulator 30.

[0047] 2, the fixed shaft 2 has a generally cylindrical shape and extends in the axial direction about a central axis J. Both ends of the fixed shaft 2 are supported by housings 50, respectively.

[0048] The fixed shaft 2 is located radially inside the bearing member 15 of the rotor 10. The fixed shaft 2 is clearance-fitted radially inside the bearing member 15. The fixed shaft 2 supports the inner circumferential surface of the bearing member 15, thereby rotatably supporting the rotor 10.

[0049] <Pump section> The pump section 40 is connected to the underside of the rotor 10. In this embodiment, the pump section 40 is an impeller. When the rotor 10 rotates about the central axis J, the pump section 40 rotates about the central axis J. In this embodiment, the pump section 40 is made of resin.

[0050] The pump section 40 has an impeller body section 41 , a shroud section 42 , and a plurality of blade sections 43 .

[0051] The impeller body 41 is connected to the lower end of the rotor 10. In this embodiment, the impeller body 41 is molded integrally with the resin part 13 of the rotor 10. In other words, the resin part 13 and the impeller body 41 are different parts of a single member. The impeller body 41 is generally disk-shaped and has a center on the central axis J.

[0052] The shroud portion 42 is a separate body from the impeller body portion 41. The shroud portion 42 is disposed below the impeller body portion 41 with a gap therebetween. The shroud portion 42 has an annular shape centered on the central axis J.

[0053] The plurality of blade portions 43 are located axially between the impeller body portion 41 and the shroud portion 42. The plurality of blade portions 43 are arranged at intervals in the circumferential direction. The lower ends of the plurality of blade portions 43 are connected to the shroud portion 42. In this embodiment, the shroud portion 42 and the plurality of blade portions 43 are different parts of a single member. The upper ends of the plurality of blade portions 43 contact the impeller body portion 41.

[0054] <Housing> The housing 50 accommodates the rotor 10 , the stator 20 , the fixed shaft 2 , the pump unit 40 , and the substrate 70 .

[0055] The housing 50 has a can (first member) 61 , a heat sink (second member) 62 , a motor cover (third member) 53 , and a pump cover (fourth member) 54 .

[0056] In this embodiment, the can 61, the heat sink 62, the motor cover 53, and the pump cover 54 are separate members. The motor cover 53 and the pump cover 54 form the outer shell of the housing 50. Meanwhile, the can 61 and the heat sink 62 form a partition 60 that separates the internal space of the outer corner. That is, the partition 60 has the can 61 as a first member and the heat sink 62 as a second member.

[0057] The partition 60 divides the interior space of the housing 50 into a first housing chamber A1 and a second housing chamber A2. The first housing chamber A1 is a space into which the fluid to be pumped by the pump 100 can enter. The first housing chamber A1 accommodates the rotor 10, the fixed shaft 2, and the pump unit 40. The second housing chamber A2 is a space that is sealed against the fluid to be pumped by the pump 100. The second housing chamber A2 accommodates the stator 20 and the substrate 70.

[0058] <Motor Cover (Third Member)> The motor cover 53 is a cylindrical member that opens downward. More specifically, the motor cover 53 has a substantially cylindrical shape centered on the central axis J. The motor cover 53 covers the rotor 10, the stator 20, the heat sink 62, and the substrate 70 from above. The motor cover 53 also separates the second housing chamber A2 from the external space. The motor cover 53 is made of, for example, a resin material.

[0059] The motor cover 53 has a top wall portion 53b, a connector protection cylinder portion 53e, a first peripheral wall portion (peripheral wall portion) 53a, and a first flange portion 53c.

[0060] The top wall portion 53b is located above the rotor 10, the stator 20, the heat sink 62, and the substrate 70. The top wall portion 53b extends along a plane perpendicular to the central axis J.

[0061] The connector protection cylinder 53e protrudes upward from the top wall 53b. The connector protection cylinder 53e is cylindrical and opens upward. The connector protection cylinder 53e surrounds and protects the connector terminals 72 connected to the circuit board 70.

[0062] The first circumferential wall portion 53a extends downward from the radial outer edge of the top wall portion 53b. The first circumferential wall portion 53a is cylindrical and centered on the central axis J. The first circumferential wall portion 53a surrounds the upper portions of the rotor 10 and the stator 20, as well as the heat sink 62 and the substrate 70 from the radial outside. The radial inner surface of the first circumferential wall portion 53a is positioned away from the radial outer surface of the core back 24.

[0063] The first flange portion 53c is annular and projects radially outward from the lower end of the first circumferential wall portion 53a.

[0064] 1, a breather 55 is provided on the top wall portion 53b of the motor cover 53. That is, the motor cover 53 has the breather 55. The breather 55 connects the second housing chamber A2 with the external space of the pump 100, and prevents the internal pressure of the second housing chamber A2 from becoming too high.

[0065] 7 is a cross-sectional view of the breather 55. The breather 55 has a base portion 55d, a vent hole 55h, a side wall portion 55a, and an upper wall portion 55b.

[0066] The base 55d is a plate-shaped portion of the ceiling wall 53b that constitutes the breather 55. The base 55d extends along a plane perpendicular to the central axis J. The base 55d has a first surface 55f facing the external space and a second surface 55g facing the second storage chamber A2.

[0067] The ventilation hole 55h penetrates the base 55d in the thickness direction. The ventilation hole 55h opens in the first surface 55f and the second surface 55g. This allows the ventilation hole 55h to communicate between the second storage chamber A2 and the external space. In this embodiment, the ventilation hole 55h is circular when viewed in the axial direction. However, the shape of the ventilation hole 55h is not limited to this embodiment. In the following description, an imaginary line extending in the axial direction about the ventilation hole 55h is referred to as the axis J1.

[0068] The opening of the ventilation hole 55h on the second storage chamber A2 side is covered with a filter 55e. The filter 55e is fixed to the second surface 55g of the base 55d by adhesive or other means. The filter 55e prevents dust and other particles from entering the second storage chamber A2 from the outside.

[0069] The upper wall portion 55b is located above the first surface 55f. The upper wall portion 55b covers the opening of the vent hole 55h facing the exterior space from above. The upper wall portion 55b has a plurality of second openings 55ba that open radially about the axis J1. The second openings 55ba are arranged at equal intervals circumferentially about the axis J1. The second openings 55ba communicate between the exterior space and the interior of the vent hole 55h.

[0070] The side wall portion 55a protrudes upward from the first surface 55f. The side wall portion 55a is cylindrical and centered on the axis J1. The side wall portion 55a surrounds the upper wall portion 55b from the radially outer side of the axis J1. The side wall portion 55a is provided with a plurality of first openings 55aa. The first openings 55aa are notched and extend from the upper end to the lower end of the side wall portion 55a. The plurality of first openings 55aa are arranged at equal intervals in the circumferential direction of the axis J1. The first openings 55aa and the second openings 55ba are arranged at positions offset in the circumferential direction of the axis J1. The first openings 55aa are provided to allow condensation formed inside the side wall portion 55a or fluid that has reached the inside of the side wall portion 55a to flow out of the side wall portion 55a.

[0071] In this embodiment, the first surface 55f of the base 55d is located above the upper surface of the top wall 53b. This embodiment prevents moisture, such as condensation water, from flowing down the upper surface of the top wall 53b from reaching the first surface 55f. This prevents moisture from flowing into the second storage chamber A2 through the ventilation holes 55h opening in the first surface 55f, thereby improving the reliability of the pump 100.

[0072] In this embodiment, the first surface 55f of the base 55d is a sloped surface that slopes downward as it moves away from the vent 55h around the vent 55h. Therefore, the sloped surface of the first surface 55f can direct moisture, such as condensation water, adhering to the first surface 55f away from the vent 55h, thereby preventing moisture from flowing into the vent 55h. Furthermore, moisture flowing along the first surface 55f flows out of the side wall 55a through the first opening 55aa in the side wall 55a. In other words, the first surface 55f can use its sloped surface to expel moisture located inside the side wall 55a to the outside of the breather 55. This embodiment prevents moisture from flowing into the second storage chamber A2 through the vent 55h.

[0073] <Pump Cover (Fourth Member)> As shown in Fig. 2, the pump cover 54 is a cylindrical member that opens upward. The pump cover 54 covers the rotor 10, the stator 20, and the pump section 40 from below. The pump cover 54 also separates the first housing chamber A1 from the external space. The pump cover 54 is made of, for example, a resin material.

[0074] The pump cover 54 has a bottom wall portion 54 a , a second peripheral wall portion 54 b , a second flange portion 54 c , an intake port portion 54 d , a discharge port portion 54 e , and the rotor support portion 52 .

[0075] The bottom wall 54a is located below the pump unit 40 and covers the pump unit 40 from below. The bottom wall 54a is generally conical, with its diameter decreasing downward and centered on the central axis J. An intake port 54d is connected to the lower end of the bottom wall 54a. The discharge port 54e is tubular and centered on the central axis J.

[0076] The second peripheral wall portion 54b extends upward from the radially outer edge of the bottom wall portion 54a. The second peripheral wall portion 54b has a cylindrical shape centered on the central axis J. The second peripheral wall portion 54b surrounds the lower portion of the stator 20 and the pump portion 40 from the radially outer side.

[0077] A tubular discharge port 54e is connected to the second peripheral wall 54b. In addition, in the first storage chamber A1, a flow path F through which fluid flowing in from the suction port 54d flows is provided radially inward of the second peripheral wall 54b and radially outward of the pump section 40. The discharge port 54e extends in a tangential direction of the flow path F. The fluid in the flow path F flows in the circumferential direction and is discharged from the discharge port 54e to the outside of the pump 100.

[0078] The second flange portion 54c is annular and surrounds the central axis J. The second flange portion 54c projects radially outward from the upper end of the second peripheral wall portion 54b.

[0079] The rotor support portion 52 has a support main body portion 52a and multiple leg portions 52b. The support main body portion 52a supports the rotor 10 from below via a washer. The fixed shaft 2 passes axially through the inside of the washer. The washer contacts the upper end of the support main body portion 52a and the lower end of the bearing member 15. The multiple leg portions 52b extend upward from the inner circumferential surface of the suction port portion 54d. The upper ends of the multiple leg portions 52b are connected to the support main body portion 52a.

[0080] <Candle (First Member)> The candle 61 is made of a resin material and forms a part of the partition portion 60.

[0081] The can 61 has a first cylindrical portion 63, a bottom portion 64, a second cylindrical portion 65, and a third flange portion 66. That is, the partition portion 60 has the first cylindrical portion 63, the bottom portion 64, the second cylindrical portion 65, and the third flange portion 66.

[0082] The first cylindrical portion 63 has a cylindrical shape centered on the central axis J. A tip end surface 63a facing upward of the first cylindrical portion 63 is a flat surface extending along a plane perpendicular to the central axis J. The first cylindrical portion 63 surrounds the rotor 10 from the radial outside. The first cylindrical portion 63 is surrounded by the stator 20 from the radial outside. In other words, the first cylindrical portion 63 is located radially between the rotor 10 and the stator 20. Because the can 61 of this embodiment is made of resin, it is less likely to obstruct the flow of magnetic flux between the rotor 10 and the stator 20.

[0083] Fig. 8 is a perspective view of the can 61 of this embodiment as seen from above. Fig. 9 is a perspective view of the can 61 of this embodiment as seen from below.

[0084] As shown in Figure 8, the first cylindrical portion 63 has a radially outer surface 63f facing radially outward. A plurality of second ribs 63d extending along the axial direction are provided on the radially outer surface 63f. The plurality of second ribs 63d are arranged at equal intervals in the circumferential direction. The second ribs 63d protrude radially outward from the radially outer surface 63f of the first cylindrical portion 63. The second ribs 63d extend over the entire axial length of the first cylindrical portion 63. The number of second ribs 63d is equal to the number of teeth 25.

[0085] The second rib 63d has a wide portion 63p and a narrow portion 63q. The wide portion 63p and the narrow portion 63q are arranged side by side in the axial direction and connected to each other. The narrow portion 63q is located above the wide portion 63p. The width of the narrow portion 63q of the second rib 63d is smaller than the width of the wide portion 63p. Note that, although the case where the second rib 63d has portions with different widths (the wide portion 63p and the narrow portion 63q) will be described here, the width of the second rib 63d may be uniform throughout its entire length.

[0086] In this specification, the "width" of a rib refers to the direction perpendicular to both the protruding direction and the extending direction of the rib. Similarly, the "width" of a groove refers to the direction perpendicular to both the recessed direction and the extending direction of the groove.

[0087] In this embodiment, the wide portion 63p of the second rib 63d faces the stator core 21 in the radial direction. On the other hand, the narrow portion 63q of the second rib 63d in this embodiment is located above the stator core 21. Note that the axial positions of the wide portion 63p and the narrow portion 63q are not limited to this embodiment. For example, the narrow portion 63q may face the stator core 21 in the radial direction.

[0088] 3 , regions of the radially outer surface 63f of the first cylindrical portion 63 located between the second ribs 63d come into contact with the radially inward surfaces of the teeth 25. According to this embodiment, the first cylindrical portion 63 supports the teeth 25 from the radially inner side. This allows the first cylindrical portion 63 to position the stator core 21 radially relative to the housing 50. Note that, although this embodiment describes a case where the first cylindrical portion 63 comes into contact with the radially inward surfaces of the teeth 25, the first cylindrical portion 63 does not necessarily have to come into contact with the teeth 25.

[0089] In the above description, the radially outer surface 63 f is in contact with the entire radially inward surface of the tooth 25. However, a protrusion may be provided on the radially outer surface 63 f, and the tip end surface of the protrusion may be in contact with a part of the radially inward surface of the tooth 25.

[0090] The wide portions 63p of the second ribs 63d are disposed between the teeth 25 adjacent to each other in the circumferential direction. According to this embodiment, the second ribs 63d can improve the rigidity of the first cylindrical portion 63 while preventing the second ribs 63d from contacting the teeth 25. This allows the stator 20 to be more stably supported by the first cylindrical portion 63. The second ribs 63d are disposed between the umbrella portions 25b of the teeth 25 adjacent to each other in the circumferential direction. Note that the second ribs 63d may contact the umbrella portions 25b of the teeth 25 on their circumferential side surfaces to support the teeth 25 from the circumferential direction.

[0091] As shown in Fig. 2, the bottom portion 64 extends radially outward from the lower (-Z) end of the first cylindrical portion 63. In this embodiment, the bottom portion 64 extends radially outward from the lower end of the first cylindrical portion 63. The bottom portion 64 has a disk shape centered on the central axis J. The bottom portion 64 covers the pump portion 40 from above and covers the stator 20 from below. The bottom portion 64 is located axially between the pump portion 40 and the stator 20.

[0092] The bottom portion 64 has a first surface 64a that faces the stator 20 in the axial direction and a second surface 64b that faces the pump portion 40 in the axial direction. A gap that is filled with a heat transfer material G1 (described later) is provided between the first surface 64a and the stator 20. More specifically, the first surface 64a is disposed axially apart from the coil 23 and the insulator 30.

[0093] As shown in FIG. 8 , a plurality of first ribs 64d extending radially are provided on the first surface 64a of the bottom portion 64. The plurality of first ribs 64d are arranged at equal intervals in the circumferential direction. The first ribs 64d protrude upward (+Z) from the first surface 64a. The first ribs 64d extend from the radially inner end of the bottom portion 64 to the radially outer end. The number of first ribs 64d is equal to the number of second ribs 63d and the number of teeth 25. The radially inner ends of the first ribs 64d are connected to the lower ends of the second ribs 63d.

[0094] The first rib 64d extends radially between circumferentially adjacent coils 23. The upper end of the first rib 64d is located higher than the lower end of the coil 23. Therefore, the first rib 64d is located between circumferentially adjacent coils 23 when viewed in the axial direction. The width of the first rib 64d decreases toward the tip end in the protruding direction (axial direction) of the first rib 64d. Therefore, the first surface 64a of the bottom portion 64 has a shape that follows the curved shape of the lower end of each coil 23.

[0095] As shown in FIG. 9 , a plurality of grooves 64e extending radially are provided on the second surface 64b of the bottom portion 64. The grooves 64e are arranged at equal intervals in the circumferential direction. The grooves 64e are recessed upward (+Z) on the second surface 64b. The number of grooves 64e is equal to the number of first ribs 64d. When viewed from the axial direction, each of the plurality of grooves 64e overlaps with a first rib 64d. In other words, at least a portion of the grooves 64e is located inside the first rib 64d. According to this embodiment, the shape of the second surface 64b is shaped to conform to the first surface 64a, making the plate thickness of the bottom portion 64 nearly uniform.

[0096] 2, the depth (axial) dimension of the groove 64e increases radially inward. The groove 64e has an opening 64k that is located at the radially inner end of the bottom portion 64 and opens onto the radially inward surface of the first cylindrical portion 63. The depth dimension of the groove 64e is greatest at the opening 64k.

[0097] According to the present embodiment, the first rib 64d is provided on the bottom portion 64, thereby improving the rigidity of the bottom portion 64. The radially inner end of the first rib 64d is connected to the lower end of the second rib 63d. According to the present embodiment, the second rib 63d can be connected to the bottom portion 64 via the first rib 64d. This further improves the rigidity of the first tubular portion 63, on which the second rib 63d is provided, via the second rib 63d, the first rib 64d, and the bottom portion 64.

[0098] According to this embodiment, a groove 64e is provided on the second surface 64b of the bottom 64, overlapping with the first rib 64d when viewed in the axial direction. Because the second surface 64b faces the pump unit 40, the fluid pumped by the pump unit 40 flows into the groove 64e. As described above, a portion of the groove 64e is located inside the first rib 64d, so the fluid flows into the first rib 64d. In addition, the first rib is located between the coils 23. According to this embodiment, the fluid can flow near the coils 23, thereby enhancing the cooling effect of the fluid on the coils 23. As a result, the coils 23 can be prevented from becoming too hot.

[0099] 2 , the upper ends of the openings 64k of the grooves 64e are located below the lower ends of the teeth 25. As described above, the first cylindrical portion 63 supports the teeth 25 from the radially inner side. According to this embodiment, the grooves 64e are provided only below the lower ends of the teeth 25, and are not provided in the portions of the first cylindrical portion 63 that support the teeth 25. Therefore, the rigidity of the portions of the first cylindrical portion 63 that support the teeth 25 is not reduced by the grooves 64e, and the support of the teeth 25 by the first cylindrical portion 63 can be stabilized.

[0100] In this embodiment, a heat transfer material (first adhesive) G1 is filled between the first surface 64a and the coil 23. The heat transfer material G1 is preferably a material with excellent insulating properties. The heat transfer material G1 is also preferably made of a material with excellent thermal conductivity. In this embodiment, the heat transfer material G1 is an adhesive. A filler may be added to the heat transfer material G1 to increase thermal conductivity. The heat transfer material G1 is filled between the first surface 64a and the coil 23 in an uncured state and then cured.

[0101] According to the present embodiment, the heat transfer material G1 is filled in the space between the first surface 64a and the coil 23, which makes it easier to transfer heat from the coil 23 to the bottom 64 compared to when an air layer is formed between the first surface 64a and the coil 23. This makes it easier to transfer heat from the coil 23 to the fluid, thereby improving the cooling effect of the coil 23.

[0102] According to this embodiment, the can 61 is disposed apart from the stator 20 as a separate component. This reduces the weight of the resin material required for the can 61 compared to when the stator 20 is insert-molded. Furthermore, compared to when the stator is insert-molded, heat from the stator 20 is less likely to be trapped inside the resin material, making it easier to release the heat from the stator 20 to the outside. In other words, this embodiment can provide a pump 100 that is lightweight and has improved cooling efficiency for the stator 20.

[0103] According to the present embodiment, the heat transfer material G1 is an adhesive that mutually fixes the first surface 64a and the coil 23. According to the present embodiment, the heat transfer material G1 can be used to fix the stator 20 to the can 61, which reduces the manufacturing cost of the pump unit 40 compared to when other members are used separately.

[0104] The heat transfer material G1 in this embodiment is preferably a thermosetting adhesive. In this case, even if the stator 20 generates heat and heat is applied to the hardened heat transfer material G1, the adhesive strength of the heat transfer material G1 can be prevented from decreasing. This can prevent the fixation between the stator 20 and the can 61 from loosening. The adhesive constituting the heat transfer material G1 is, for example, a one-component reactive epoxy adhesive.

[0105] As shown in FIG. 2 , the second cylindrical portion 65 has a cylindrical shape that protrudes upward from the bottom portion 64. In this embodiment, the second cylindrical portion 65 protrudes upward from the radial outer edge of the bottom portion 64. The second cylindrical portion 65 opens upward. In this embodiment, the second cylindrical portion 65 has a substantially cylindrical shape centered on the central axis J. The second cylindrical portion 65 is surrounded from the radial outside by the second peripheral wall portion 54b of the pump cover 54. A sealing member such as an O-ring is disposed between the second cylindrical portion 65 and the second peripheral wall portion 54b.

[0106] The second cylindrical portion 65 has a lower cylindrical portion 65c and an upper cylindrical portion 65b. The upper cylindrical portion 65b is connected to the upper side of the lower cylindrical portion 65c. The inner diameter of the upper cylindrical portion 65b is larger than the inner diameter of the lower cylindrical portion 65c.

[0107] The second cylindrical portion 65 has an upwardly facing stepped surface 65d. The stepped surface 65d connects the upper end of the radially inward surface of the lower cylindrical portion 65c to the lower end of the radially inner surface 65f of the upper cylindrical portion 65b. The stepped surface 65d is a flat surface perpendicular to the axial direction.

[0108] 2, the step surface 65d faces the lower end surface of the core back 24 with a gap therebetween. That is, a gap is provided between the step surface 65d and the core back 24. As described above, a gap is also provided between the coil 23 and the bottom 64. In this manner, the stator 20 is disposed with a gap between it and the surface of the housing 50 facing upward in the axial direction. Furthermore, a heat transfer material G1 is filled between the stator 20 and the surface of the housing 50 facing upward, thereby fixing the stator 20 and the housing 50 together.

[0109] According to this embodiment, the stator 20 is positioned in the axial direction relative to the housing 50 by hardening the heat transfer material G1. Therefore, the stator 20 can be axially positioned relative to the housing 50 while the heat transfer material G1 is in an unhardened state.

[0110] As shown in Fig. 8, the upper cylindrical portion 65b of the second cylindrical portion 65 has a radially inner surface 65f that faces radially inward. That is, the second cylindrical portion 65 has the radially inner surface 65f. The radially inner surface 65f is a cylindrical surface centered on the central axis J. A plurality of protrusions 65a are provided on the radially inner surface 65f. Each of the plurality of protrusions 65a protrudes radially inward.

[0111] As shown in Fig. 3, the radially inner surface 65f surrounds the core back 24 from the radially outer side. The multiple protrusions 65a contact the surface of the core back 24 facing radially outward. The core back 24 is lightly press-fitted inside the multiple protrusions 65a. The multiple protrusions 65a support the core back 24 from the radially outer side. It is sufficient that two or more multiple protrusions 65a are provided so as to surround the periphery of the central axis J. In this case, the core back 24 can be supported from the radially outer side.

[0112] According to this embodiment, the multiple protrusions 65a can support the core back 24 from the radially outer side. Therefore, the stator 20 can be temporarily fixed to the housing 50 until the housing 50 and the stator 20 are adhesively fixed together with the heat transfer material G1. Furthermore, since the core back 24 is temporarily fixed by light press-fitting inside the multiple protrusions 65a, the axial position of the stator 20 relative to the housing 50 can be easily determined.

[0113] As shown in FIG. 2 , the third flange portion 66 extends radially outward from the upper end of the second cylindrical portion 65. The third flange portion 66 has a generally annular shape centered on the central axis J. The third flange portion 66 is located axially between the first flange portion 53c and the second flange portion 54c. The third flange portion 66 contacts the first flange portion 53c and the second flange portion 54c. A seal member such as an O-ring seals the gap between the first flange portion 53c and the third flange portion 66.

[0114] <Heat sink (second member)> The heat sink 62 is made of a metal material with excellent thermal conductivity, such as a copper alloy or an aluminum alloy. The heat sink 62 may also be made of a resin material with excellent thermal conductivity. The heat sink 62 constitutes a part of the partition 60.

[0115] The heat sink 62 has a lid portion 67 and a heat sink body 69. That is, the partition portion 60 has the lid portion 67 and the heat sink body 69. The lid portion 67 is cylindrical and centered on the central axis J. The lid portion 67 covers the rotor 10 from the upper side (+Z). The heat sink body 69 extends radially outward from the lid portion 67. The heat sink body 69 is plate-shaped and extends along a plan view perpendicular to the axial direction.

[0116] The heat sink 62 also has a cooling surface 62g facing upward. The cooling surface 62g is a surface facing upward on both the lid portion 67 and the heat sink body 69. The cooling surface 62g is a flat surface extending along a plane perpendicular to the central axis J. The cooling surface 62g contacts the substrate 70 from below via the heat transfer material G3. The heat sink 62 absorbs heat from the substrate 70 at the cooling surface 62g, thereby cooling the substrate 70.

[0117] Fig. 10 is a perspective view of the heat sink 62 of this embodiment as seen from above. Fig. 11 is a perspective view of the heat sink 62 of this embodiment as seen from below.

[0118] 10 , the downward-facing surface of the lid portion 67 is provided with a substantially circular holding recess 67a centered on the central axis J and a circular annular groove 68 centered on the central axis J. In addition, the downward-facing surface of the lid portion 67 is provided with an uneven shape to ensure a large surface area and improve cooling performance.

[0119] 2, the upper end of the fixed shaft 2 is inserted into and fixed in the holding recess 67a. In this way, the lid 67 holds the upper end of the fixed shaft 2.

[0120] The upper end of the first cylindrical portion 63 is inserted into and fixed to the annular groove 68. An adhesive (second adhesive) G2 is filled and hardened between the first cylindrical portion 63 and the inner surface of the annular groove 68. This fixes the upper end of the first cylindrical portion 63 to the inner surface of the annular groove 68.

[0121] FIG. 12 is an enlarged perspective cross-sectional view showing the annular groove 68 and the first cylindrical portion 63 in the partition 60 of this embodiment.

[0122] The inner surface of the annular groove 68 is provided with a first wall surface 68a facing radially inward, a second wall surface 68b facing downward, and a third wall surface 68c facing radially outward. The second wall surface 68b corresponds to the bottom surface of the annular groove 68 and extends annularly about the central axis J. The first wall surface 68a extends downward from the radially outer end of the second wall surface 68b. The third wall surface 68c extends downward from the radially inner end of the second wall surface 68b.

[0123] The first wall surface 68a is disposed radially with a gap interposed between it and the radially outer surface 63f of the first cylindrical portion 63. The gap between the first wall surface 68a and the radially outer surface 63f is filled with adhesive G2.

[0124] As shown in Fig. 11, the first wall surface 68a is provided with a plurality of grooves 68g. The grooves 68g extend along the axial direction. The grooves 68g are arranged at equal intervals in the circumferential direction. The grooves 68g are provided over the entire axial length of the first wall surface 68a and open downward.

[0125] As shown in FIG. 12 , the narrow portion 63q of the second rib 63d of the first cylindrical portion 63 is inserted into the recessed groove 68g. The width of the second rib 63d is larger than the width of the narrow portion 63q. According to this embodiment, the first wall surface 68a of the annular groove 68 and the radially outer surface 63f of the first cylindrical portion 63, which face each other, can each be formed with an uneven shape. This allows a large facing area between the first wall surface 68a and the radially outer surface 63f to be secured, thereby ensuring a large bonding area between the first wall surface 68a and the radially outer surface 63f. As a result, the adhesive strength between the first wall surface 68a and the radially outer surface 63f provided by the adhesive G2 can be increased. Furthermore, the depth of the annular groove 68 can be reduced to ensure sufficient bonding strength, allowing the partition 60 to be miniaturized in the axial direction.

[0126] The second wall surface 68b faces the tip surface 63a of the first cylindrical portion 63 in the axial direction. As shown in FIG. 11 , the second wall surface 68b is provided with a plurality of protrusions 68d that protrude downward. The plurality of protrusions are arranged at equal intervals in the circumferential direction. In this embodiment, three protrusions are provided on the second wall surface 68b. The lower end surfaces of the plurality of protrusions 68d are flat surfaces that are arranged on the same plane as one another.

[0127] 12 , a gap is provided between the first cylindrical portion 63 and an area of ​​the second wall surface 68b other than the protrusion 68d. The gap between the second wall surface 68b and the first cylindrical portion 63 is filled with adhesive G2. Meanwhile, as shown in FIG. 2 , the protrusion 68d contacts the tip surface of the first cylindrical portion 63. According to this embodiment, the heat sink 62 can be positioned axially relative to the can 61 by the protrusion 68d contacting the first cylindrical portion 63 in the axial direction.

[0128] According to this embodiment, by providing the protrusion 68d, the axial contact point of the heat sink 62 with the can 61 can be limited to the tip surface of the protrusion 68d. Therefore, by controlling the positional accuracy of only the tip surface of the protrusion 68d, it is possible to ensure the axial positional accuracy of the can 61 and the heat sink 62.

[0129] In this embodiment, the second wall surface 68b is described as having three protrusions 68d. However, the above-described effect can be achieved as long as at least one protrusion 68d is provided on the second wall surface 68b. It is also preferable that the second wall surface 68b be provided with three or more protrusions 68d arranged at equal intervals in the circumferential direction. In this case, the contact points between the can 61 and the heat sink 62 can be arranged at equal intervals around the central axis J in a balanced manner, making it easier to prevent the can 61 from tilting relative to the heat sink 62.

[0130] As shown in Fig. 12 , the third wall surface 68c faces a radially inner surface 63g facing radially inward of the first cylindrical portion 63. The third wall surface 68c is fitted to the radially inner surface 63g with a clearance fit. This positions the heat sink 62 in the radial direction relative to the can 61. In the example shown in Fig. 12 , no adhesive G2 is provided between the third wall surface 68c and the radially inner surface 63g. However, the adhesive G2 may also be provided between the third wall surface 68c and the radially inner surface 63g.

[0131] In this embodiment, the adhesive G2 filled between the first cylindrical portion 63 and the inner surface of the annular groove portion 68 is a silicone adhesive. In this embodiment, the can 61 is made of a resin material to ensure insulation from the stator 20. On the other hand, the heat sink 62 is made of a metal material to enhance heat absorption from the substrate 70. Therefore, the can 61 and the heat sink 62 have significantly different linear expansion coefficients. Stress due to the difference in linear expansion coefficients may be applied to the fastening portion between the can 61 and the heat sink 62. According to this embodiment, by using a silicone adhesive with a low elastic modulus as the adhesive G2 between the can 61 and the heat sink 62, stress applied to the fastening portion between the can 61 and the heat sink 62 can be alleviated, thereby improving the reliability of the fastening between the can 61 and the heat sink 62.

[0132] Furthermore, by using a silicone adhesive as the adhesive G2, the adhesive G2 can be used as a sealant. In this case, it is possible to prevent fluid from seeping from the first housing chamber A1 to the second housing chamber A2 through the gap between the first cylindrical portion 63 and the annular groove portion 68. In this case, the sealing member 4 (described below) disposed between the can 61 and the heat sink 62 may be omitted.

[0133] As shown in FIG. 12 , the lid portion 67 of this embodiment has an opposing surface 67f that is located radially inward of the annular groove portion 68 and faces radially outward. The opposing surface 67f is a cylindrical surface centered on the central axis J. The opposing surface 67f is located below the annular groove portion 68. The opposing surface 67f faces a radially inner surface 63g of the first cylindrical portion 63 with a radial gap therebetween. A sealing member 4 such as an O-ring is disposed between the opposing surface 67f and the radially inner surface 63g. The sealing member 4 prevents fluid from penetrating from the first housing chamber A1 to the second housing chamber A2 through the gap between the can 61 and the heat sink 62.

[0134] According to this embodiment, the sealing member 4 is disposed closer to the first storage chamber A1 than the adhesive G2 in the path of fluid penetration from the first storage chamber A1 to the second storage chamber A2. According to this embodiment, the sealing member 4 prevents the fluid in the first storage chamber A1 from reaching the adhesive G2. This prevents the fluid from acting to impair the adhesive strength of the adhesive G2. Furthermore, according to this embodiment, even when the adhesive G2 is in an uncured state, it is possible to perform an airtightness test or a waterproof test, such as by applying pressure to the first storage chamber A1. Therefore, during the assembly process of the pump 100, the takt time required for the adhesive G2 to cure can be saved, thereby shortening the time required for the assembly process.

[0135] 13 is a cross-sectional perspective view showing a portion of the outer edge portion 69f of the heat sink 62 of this embodiment. The heat sink body 69 is provided with a fixing portion 69a for fixing the substrate 70. The fixing portion 69a has a substrate support surface 69c facing upward. The substrate support surface 69c contacts the lower surface of the substrate 70 and supports the substrate 70 from below. In other words, the partition portion 60 supports the substrate 70 from below.

[0136] The fixing portion 69a is provided with a screw hole 69b extending in the axial direction. The screw hole 69b opens upward on the substrate support surface 69c. A fixing screw 8 inserted into a fixing hole 71a of the substrate 70 is fastened into the screw hole 69b. In this way, the substrate 70 is fixed to the partition portion 60.

[0137] 13 , the first peripheral wall portion 53a of the motor cover 53 has an inner surface 53aa that faces radially inward. The inner surface 53aa surrounds the heat sink 62 from the radially outer side. The inner surface 53aa also surrounds the radially outer outer edge portion 69f of the heat sink 62 from the radially outer side.

[0138] The inner surface 53aa is provided with multiple crush ribs (third ribs) 53d extending axially. The multiple crush ribs 53d are arranged in the circumferential direction. The radially inward-facing tip surfaces of the crush ribs 53d are provided with inclined surfaces 53da that slope radially outward as they extend downward. In other words, the protruding height of at least some of the crush ribs 53d gradually decreases as they extend downward.

[0139] In the assembly process for the pump 100 of this embodiment, the motor cover 53 is attached to the partition 60 from above. When the motor cover 53 is attached to the partition 60 from above, the crush rib 53d contacts the outer edge 69f of the heat sink 62 at the inclined surface 53da and undergoes plastic deformation. This causes the motor cover 53 to press the heat sink 62 downward, preventing the heat sink 62 from moving upward relative to the can 61. Therefore, when attaching the motor cover 53 to the partition 60, even if the adhesive G2 is in an uncured state, the heat sink 62 is less likely to shift position relative to the can 61. Furthermore, even if an airtightness test or a waterproof test is performed by applying pressure to the first housing chamber A1 while the adhesive G2 is in an uncured state, the heat sink 62 is prevented from moving upward relative to the can 61.

[0140] 2, the substrate 70 is located above the partition 60. More specifically, the substrate 70 is located above the heat sink 62. The substrate 70 has a substrate main body 71 and electronic components (not shown) mounted on the upper surface of the substrate main body. The substrate 70 controls the power supplied to the stator 20, thereby controlling the rotation of the rotor 10.

[0141] The board body 71 extends along a plane perpendicular to the central axis J. That is, the board 70 extends along a plane perpendicular to the central axis J. Electronic components mounted on the board body 71 include, for example, capacitors and transistors that constitute an inverter circuit. In addition, connector terminals 72 for connecting the pump 100 to external devices are connected to the board body 71.

[0142] As shown in Figure 4, the substrate body 71 is provided with a plurality of through holes 71h. Terminal pins 3a of the terminal member 3, which are connected to the coil 23, are inserted into the through holes 71h from below. In the pump 100 of this embodiment, the axial positions of the terminal member 3 and the substrate 70 may vary due to stacking tolerances of the component precision of the components interposed between the can 61 and the terminal member 3. Furthermore, in the pump 100 of this embodiment, if the axial position of the terminal member 3 is significantly misaligned from the axial position of the substrate 70, the connection between the terminal member 3 and the substrate 70 may become unstable.

[0143] 2, in the pump 100 of this embodiment, a gap is provided between the stator 20 and the upward surface of the housing 50, in which a heat transfer material (first adhesive) G1 is disposed. Therefore, the axial position of the stator 20 relative to the can 61 can be easily adjusted by adjusting the size of the gap. That is, according to this embodiment, the position of the terminal member 3, which is a part of the stator 20, can be adjusted in the axial direction.

[0144] In the assembly process of the pump 100 of this embodiment, the stator 20 is assembled first.

[0145] Next, after applying uncured heat transfer material G1 to the first surface 64a of the can 61, the stator 20 is assembled to the can 61. At this time, the stator core 21 is lightly press-fitted into the inside of the multiple protrusions 65a of the can 61, as shown in FIG. 3 . This allows the axial position of the stator 20 to be adjusted relative to the can 61 while the stator 20 is held by the can 61. More specifically, using a jig or the like, the terminal member 3 is positioned in the axial direction relative to the surface where the heat sink 62 is positioned axially relative to the can 61 (in this embodiment, the tip surface 63a of the can 61).

[0146] Next, the first cylindrical portion 63 of the can 61 is inserted into the annular groove 68 of the heat sink 62 filled with adhesive G2 to assemble the partition portion 60. Furthermore, the motor cover 53, fixed shaft, rotor 10, pump portion 40, and pump cover 54 are assembled to the partition portion 60. At this time, as shown in FIG. 13 , the crush rib 53d of the motor cover 53 is pressed against the outer edge 69f of the heat sink 62 to prevent the heat sink 62 from moving upward relative to the can 61. Tests such as airtightness tests and waterproof tests are performed in this state. Finally, the adhesive G2 and the heat transfer material G1 are cured.

[0147] Although the embodiments and modifications of the present invention have been described above, the configurations and combinations thereof in the embodiments and modifications 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. For example, the number and shape of each rib or groove are not limited to the above-described embodiments.

[0148] The present technology can be configured as follows. (1) A rotor rotatable about a central axis, a stator positioned radially outward of the rotor and surrounding the rotor, a pump section connected to one axial side of the rotor, and a housing accommodating the rotor, the stator, and the pump section, wherein the stator has: an annular core back centered on the central axis, and a stator core having a plurality of teeth extending radially inward from the core back and arranged circumferentially, and a plurality of coils attached to the teeth, the housing has a partition section that divides an internal space into a first accommodating chamber that accommodates the rotor and the pump section, and a second accommodating chamber that accommodates the stator, the partition section having: a lid section that covers the rotor from the other axial side, a cylindrical first cylindrical section centered on the central axis and positioned radially between the rotor and the stator, and a bottom section that extends radially outward from an end on one axial side of the first cylindrical section and is positioned axially between the pump section and the stator, the bottom section A pump having a first surface facing the stator in the axial direction and a second surface facing the pump portion in the axial direction, wherein a first rib extending radially is provided on the first surface between circumferentially adjacent coils, and a groove extending radially and overlapping the first rib is provided on the second surface when viewed in the axial direction. (2) The pump described in (1), wherein the first cylindrical portion supports the teeth from the radially inner side, the groove has an opening that opens on a surface facing radially inward of the first cylindrical portion, and an end on the other axial side of the opening is located axially to one side of an end on one axial side of the tooth. (3) The pump described in (1) or (2), wherein a heat transfer material is filled between the first surface and the coil. (4) The pump described in (3), wherein the heat transfer material is a first adhesive that fixes the first surface and the coil to each other.(5) The pump according to any one of (1) to (4), further comprising: a substrate located on the other axial side of the partition portion and extending along a plane perpendicular to the central axis, wherein the stator has terminal members connected to the coil and a terminal support member supporting the terminal members on the other axial side of the stator core, wherein the substrate is supported by the partition portion from one axial side, wherein the stator is disposed across a gap from a surface of the housing facing upward in the axial direction, and wherein the terminal members are inserted into through holes in the substrate from one axial side. (6) The pump according to (5), wherein the terminal support member is an insulator provided between the coil and the stator. (7) The pump according to (5) or (6), wherein the partition portion has a second cylindrical portion protruding from the bottom portion toward the other axial side, the second cylindrical portion has a radially inner surface that is a cylindrical surface centered on the central axis and surrounds the core back from the radially outer side, and the radially inner surface of the second cylindrical portion is provided with a plurality of protrusions that are arranged circumferentially and each protrusion contacts a surface of the core back facing radially outward. (8) The partition portion has a first member having the first cylindrical portion and the bottom portion, and a second member having the lid portion, the lid portion is provided with an annular groove portion having an annular shape centered on the central axis, the other axial end of the first cylindrical portion is inserted into the annular groove portion, a second adhesive is filled between the first cylindrical portion and the inner surface of the annular groove portion, a plurality of second ribs arranged in the circumferential direction and extending along the axial direction are provided on the radially outer surface of the first cylindrical portion, and a first wall surface facing radially inward of the inner surface of the annular groove is provided with a plurality of recessed groove portions extending along the axial direction and into which the second ribs are inserted, the pump described in any one of (1) to (7). (9) The pump according to (8), wherein a second wall surface of the inner surface of the annular groove facing one axial side is provided with at least one convex portion protruding to one axial side, and a tip surface of the convex portion facing one axial side is in contact with a tip surface of the first cylindrical portion facing the other axial side. (10) The pump according to (9), wherein three or more of the convex portions are provided on the second wall surface and are arranged at equal intervals in the circumferential direction. (11) The pump according to any one of (8) to (10), wherein the second adhesive is a silicone adhesive.(12) The pump according to any one of (8) to (11), wherein the cover portion has an opposing surface opposing a radially inner surface of the first cylindrical portion, and a sealing member is disposed between the opposing surface and the radially inner surface of the first cylindrical portion. (13) The pump according to any one of (8) to (12), wherein the housing has a third member covering the second member from the other axial side, the third member having a peripheral wall portion surrounding the second member from the radially outer side, a third rib extending along the axial direction provided on a surface facing the radially inner side of the peripheral wall portion, and the third rib contacts an outer edge portion on the radially outer side of the second member.

[0149] 3...Terminal member, 4...Sealing member, 10...Rotor, 20...Stator, 21...Stator core, 23...Coil, 24...Core back, 25...Teeth, 30...Insulator (terminal support member), 36...Terminal support portion, 40...Pump portion, 50...Housing, 53...Motor cover (third member), 53a...First peripheral wall portion (peripheral wall portion), 53aa...Inner surface, 53d...Crush rib (third rib), 55f, 64a...First surface, 55g, 64b...Second surface, 60...Partition portion, 61...Can (first member), 62...Heat sink (second member), 63...First cylindrical portion , 63a...tip surface, 63d...second rib, 63f...radially outer surface, 63g, 65f...radially inner surface, 64...bottom, 64d...first rib, 64e...groove, 64k...opening, 65...second cylindrical portion, 65a...projection portion, 67...lid portion, 67f...opposing surface, 68...annular groove portion, 68a...first wall surface, 68b...second wall surface, 68d...convex portion, 68g...concave groove portion, 69f...outer edge portion, 70...substrate, 71h...through hole, 100...pump, A1...first storage chamber, A2...second storage chamber, G1...heat transfer material (first adhesive), G2...adhesive (second adhesive), J...central axis, J1...axis

Claims

1. A rotor rotatable about a central axis, a stator positioned radially outward of the rotor and surrounding the rotor, a pump section connected to one axial side of the rotor, and a housing accommodating the rotor, the stator, and the pump section, wherein the stator has: an annular core back centered on the central axis, and a stator core having a plurality of teeth extending radially inward from the core back and arranged circumferentially, and a plurality of coils attached to the teeth, the housing has a partition section that divides the internal space into a first accommodating chamber that accommodates the rotor and the pump section, and a second accommodating chamber that accommodates the stator, the partition section having: a lid section that covers the rotor from the other axial side, a first cylindrical section that is cylindrical and centered on the central axis and positioned radially between the rotor and the stator, and a bottom section that extends radially outward from the end on one axial side of the first cylindrical section and is positioned axially between the pump section and the stator, the bottom section a first surface facing the stator in the axial direction; and a second surface facing the pump section in the axial direction, wherein a first rib is provided on the first surface and extends radially between adjacent coils in the circumferential direction, and a groove is provided on the second surface and extends radially, overlapping the first rib when viewed in the axial direction.

2. A pump as described in claim 1, wherein the first cylindrical portion supports the teeth from the radially inner side, the groove has an opening that opens to a surface of the first cylindrical portion facing radially inward, and the end of the opening on the other axial side is located on one axial side of the end of one axial side of the teeth.

3. The pump according to claim 1, wherein a heat transfer material is filled between the first surface and the coil.

4. The pump according to claim 3, wherein the heat transfer material is a first adhesive that fixes the first surface and the coil to each other.

5. A pump as claimed in any one of claims 1 to 4, comprising a base plate located on the other axial side of the partition section and extending along a plane perpendicular to the central axis, the stator having terminal members connected to the coils and a terminal support member supporting the terminal members on the other axial side of the stator core, the base plate being supported by the partition section from one axial side, the stator being arranged with a gap between it and a surface of the housing facing upward in the axial direction, and the terminal members being inserted into through holes in the base plate from one axial side.

6. The pump according to claim 5, wherein the terminal support member is an insulator provided between the coil and the stator.

7. A pump as described in claim 5, wherein the partition portion has a second cylindrical portion protruding from the bottom portion to the other axial side, the second cylindrical portion having a radially inner surface that is a cylindrical surface centered on the central axis and surrounds the core back from the radially outer side, and the radially inner surface of the second cylindrical portion is provided with a plurality of protrusions that are arranged circumferentially and each protrusion contacts a surface of the core back that faces radially outward.

8. The pump described in claim 1, wherein the partition comprises: a first member having the first cylindrical portion and the bottom portion; and a second member having the lid portion; the lid portion is provided with an annular groove portion having an annular shape centered on the central axis; the other axial end of the first cylindrical portion is inserted into the annular groove portion; a second adhesive is filled between the first cylindrical portion and the inner surface of the annular groove portion; the radially outer surface of the first cylindrical portion is provided with a plurality of second ribs arranged in the circumferential direction and extending along the axial direction; and a first wall surface of the inner surface of the annular groove facing radially inward is provided with a plurality of recessed groove portions extending along the axial direction and into which the second ribs are inserted.

9. A pump as described in claim 8, wherein a second wall surface of the inner surface of the annular groove portion facing one axial side is provided with at least one protrusion protruding to one axial side, and the tip surface of the protrusion facing one axial side is in contact with the tip surface of the first cylindrical portion facing the other axial side.

10. The pump according to claim 9, wherein the second wall surface is provided with three or more of the protrusions arranged at equal intervals in the circumferential direction.

11. The pump according to claim 8, wherein the second adhesive is a silicone adhesive.

12. The pump according to claim 8, wherein the cover portion has an opposing surface that faces the radially inner surface of the first cylindrical portion, and a sealing member is disposed between the opposing surface and the radially inner surface of the first cylindrical portion.

13. A pump as described in claim 8, wherein the housing has a third member that covers the second member from the other axial side, the third member has a peripheral wall portion that surrounds the second member from the radially outer side, and a third rib extending along the axial direction is provided on a surface of the peripheral wall portion facing radially inward, and the third rib contacts the radially outer outer edge portion of the second member.

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