ELECTRIC PUMP

Abstract

One embodiment of the electric pump according to the invention comprises a rotatable rotor with a central axis as its center point, a stator positioned radially on the outside of the rotor, a pump section connected axially to one side of the rotor, a switching plate positioned axially on the other side of the stator, a housing having a pump receiving section that receives the pump section inside, a cover that covers the switching plate axially from the other side, and a plastic molded section that connects the housing and the cover, being in contact with at least a part of the housing and at least a part of the cover.

Description

TECHNICAL AREA

[0001] The present invention relates to an electric pump. STATE OF THE ART

[0002] An electric pump is known which comprises a motor housing, a pump housing and a cover of a drive housing, each of which are different components (for example, patent document 1). DOCUMENTS OF THE STATE OF TECHNOLOGY Patent documents

[0003] Patent document 1 International Disclosure 2012 / 042971 BRIEF DESCRIPTION OF THE INVENTION Problems to be solved by the invention

[0004] The assembly of the aforementioned electric pump requires a worker or similar person to perform the process of fixing the pump housing to the motor housing and the process of fixing the cover to the drive housing, which is designed as a single unit with the motor housing. Therefore, the problem arises that the labor hours and the time required to manufacture an electric pump increase.

[0005] In view of the foregoing circumstances, an object of the present invention is to provide an electric pump which has a design which reduces the labor hours and time required for its manufacture. Means of solving the task

[0006] One embodiment of the electric pump according to the invention comprises a rotatable rotor with a central axis as its center point, a stator positioned radially on the outside of the rotor, a pump section connected axially to one side of the rotor, a switching plate positioned axially on the other side of the stator, a housing having a pump receiving section that receives the pump section inside, a cover that covers the switching plate axially from the other side, and a plastic molded section that connects the housing and the cover, being in contact with at least a part of the housing and at least a part of the cover. Effect of the invention

[0007] According to one embodiment of the present invention, the working hours and time required to manufacture an electric pump can be reduced. BRIEF DESCRIPTION OF THE FIGURES Fig. Figure 1 is a perspective view showing an electric pump according to a first embodiment. Fig. Figure 2 is a sectional view showing the electric pump according to the first embodiment. Fig. Figure 3 is a perspective view showing a stator arrangement according to the first embodiment. Fig. Figure 4 is a sectional view showing the electric pump according to the first embodiment. Fig. Figure 5 is a perspective view showing a housing according to the first embodiment. Fig. Figure 6 is a perspective view showing a cover arrangement according to the first embodiment. Fig. Figure 7 is a sectional view showing part of the electric pump according to the first embodiment, and is a view showing third circular protrusions. Fig. Figure 8 is a sectional view showing part of the manufacturing process of the electric pump according to the first embodiment. Fig. Figure 9 is a sectional view showing another part of the manufacturing process of the electric pump according to the first embodiment. Fig. Figure 10 is a sectional view, which in turn shows another part of the manufacturing process of the electric pump according to the first embodiment. Fig. Figure 11 is a sectional view showing part of the process of forming the plastic mold section according to the first embodiment. Fig. Figure 12 is a sectional view showing part of the electric pump according to a second embodiment. Fig. Figure 13 is a sectional view showing part of the electric pump according to a third embodiment. Fig. Figure 14 is a sectional view showing part of the electric pump according to a fourth embodiment. FORMS OF EXECUTION OF THE INVENTION

[0008] In each drawing, the central axis J is shown as conceived with respect to the pump in the embodiments described below. In the following explanation, the axial direction of the central axis J is simply referred to as the "axial direction," a direction perpendicular to the central axis J is simply referred to as the "radial direction," and a circumferential direction with the central axis J as its center point is simply referred to as the "circumferential direction." The Z-axis shown in each drawing indicates the direction in which the central axis J extends. In the following explanation, the side toward which the arrow of the Z-axis points in the axial direction (+Z-side) is referred to as "top," and the side opposite to the side toward which the arrow of the Z-axis points in the axial direction (-Z-side) is referred to as "bottom."

[0009] In the embodiments described below, the underside corresponds to "one side in the axial direction" and the top side corresponds to "the other side in the axial direction". Furthermore, "top" and "bottom" are merely designations to clarify the relative position of individual parts, and the actual relative arrangement may be a different relative position than that indicated by these designations. First embodiment

[0010] The electric pump 100 of the present, in Fig. 1 and Fig. The embodiment shown in Figure 2 is a water pump that pumps water. As in Fig. As shown in Figure 2, the electric pump 100 of the present embodiment comprises a rotor 10, a stator arrangement 20, a pump section 40, a housing 50, a cover arrangement 60, a plastic molded section 70, a switching plate 95 and a plurality of electronic components 96.

[0011] The rotor 10 can rotate about the central axis J. The rotor 10 comprises a rotor core 11, a magnet 12, a first rotor plastic section 13, a second rotor plastic section 14, and a bearing section 15. The rotor core 11 has a ring shape that surrounds the central axis J. The magnet 12 is arranged radially on the outer surface of the rotor core 11. The magnet 12 is, for example, arranged in multiples at intervals around the circumference.

[0012] The first rotor plastic section 13 has an approximate cylindrical shape that surrounds the central axis J and extends axially. The first rotor plastic section 13 covers the rotor core 11 and the plurality of magnets 12 from the outside in the radial direction and on both sides in the axial direction. The rotor core 11 and the plurality of magnets 12 are embedded in the first rotor plastic section 13. In the present embodiment, the first rotor plastic section 13 is manufactured by overmolding as an insert element for the rotor core 11 and the plurality of magnets 12.

[0013] The second rotor plastic section 14 has an approximate cylindrical shape that surrounds the central axis J and extends axially. The second rotor plastic section 14 is positioned radially on the inside of the rotor core 11. The second rotor plastic section 14 covers an inner surface of the rotor core 11 radially. The second rotor plastic section 14 has a portion that is axially inserted into the first rotor plastic section 13. The second rotor plastic section 14 is fixed to the first rotor plastic section 13. In the present embodiment, the second rotor plastic section 14 is manufactured by overmolding as an insert element of the molded section, which is formed in one piece by overmolding and consists of the rotor core 11, the plurality of magnets 12, the first rotor plastic section 13, and the bearing 15.

[0014] The bearing 15 has a tubular shape into which a fixing shaft 30, described below, is guided in the axial direction. In the present embodiment, the bearing 15 has an approximate cylindrical shape that surrounds the central axis J and extends in the axial direction.

[0015] The bearing 15 is a section rotatably supported by the fixing shaft 30. The bearing 15 is positioned radially on the inside of the second rotor plastic section 14. The outer circumferential side of the bearing 15 is fixed to the inner circumferential side of the second rotor plastic section 14. The bearing 15 is made of plastic, for example. The bearing 15 opens axially on both sides.

[0016] The stator assembly 20 comprises a stator 20a, a stator plastic section 24, and a fixing shaft 30. In other words, the electric pump 100 includes the stator 20a, the stator plastic section 24, and the fixing shaft 30. The stator 20a is positioned radially on the outside of the rotor 10. The stator 20a surrounds the rotor 10. The stator 20a faces the rotor 10 via a plastic section forming the stator plastic section 24 and a radial gap. The stator 20a has a stator core 21, an insulator 22 attached to the stator core 21, and a plurality of coils 23 attached to the stator core 21 via the insulator 22.

[0017] The stator core 21 is positioned radially on the outside of 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 formed, for example, by a plurality of plate components stacked axially. The plurality of plate components forming the stator core 21 are, for example, electromagnetic steel plates. The stator core 21 has an annular core back section 21a surrounding the rotor 10 and a plurality of teeth 21b extending radially from the core back section 21a to the inside. The plurality of teeth 21b are arranged at intervals in the circumferential direction. The plurality of coils 23 are attached to the plurality of teeth 21b via the insulator 22.

[0018] The locking shaft 30 extends axially. More precisely, the locking shaft 30 has an approximately axially extending cylindrical shape with the central axis J at its center. The locking shaft 30 is positioned radially on the inside of the bearing 15 on the rotor 10. The locking shaft 30 is guided axially into the inside of the bearing 15 in the radial direction. The locking shaft 30 projects axially beyond the bearing 15 on both sides. The locking shaft 30 has a clearance fit radially on the inside of the bearing 15. By supporting the inner circumferential surface of the bearing 15, the locking shaft 30 rotatably supports the rotor 10.

[0019] The upper end of the fixing shaft 30 is embedded in the partition section 24a of the stator plastic section 24, as described below. The upper end of the fixing shaft 30 is held by the partition section 24a. The fixing shaft 30 extends downwards from the partition section 24a. The lower end of the fixing shaft 30 is positioned further down than the rotor mounting section 24r, as described below. A pair of concave shaft sections 31 are provided in the portion of the fixing shaft 30 embedded in the partition section 24a, and these concave sections are arranged radially around the central axis J. By positioning a plastic section forming the partition section 24a within the pair of concave shaft sections 31, the fixing shaft 30 is prevented from detaching from the partition section 24a.

[0020] The stator plastic section 24 is made of plastic. At least a portion of the stator 20a is embedded in the stator plastic section 24. In the present embodiment, the entire stator 20a is embedded in the stator plastic section 24. The stator 20a and the fixing shaft 30 are connected by the stator plastic section 24. The stator plastic section 24 has a portion that covers the stator 20a radially from the inside, a portion that covers the stator 20a radially from the outside, a portion that covers the stator 20a from above, and a portion that covers the stator 20a from below. In the present embodiment, the entire outer circumference of the stator 20a is covered by the stator plastic section 24 and is not exposed to the outside of the stator assembly 20.

[0021] The stator plastic section 24 comprises the stator plastic main section 24s. The stator plastic main section 24s has a tubular shape that surrounds the central axis J and opens downwards. In the present embodiment, the stator plastic main section 24s has an approximately cylindrical shape that opens downwards, with the central axis J as its center point. The stator plastic main section 24s comprises the partition section 24a and a first annular plastic section 24b. In other words, the stator plastic section 24 comprises the partition section 24a and a first annular plastic section 24b.

[0022] The partition section 24a is a wall that axially separates the interior of the rotor mounting section 24r described below and the interior of the circuit board mounting section 90. The partition section 24a widens radially. The central axis J leads into the partition section 24a. As in Fig. As shown in Figure 3, the partition section 24a in the present embodiment has a circular shape when viewed in the axial direction, the center of which coincides with the central axis J.

[0023] The first annular plastic section 24b has a ring shape that surrounds the central axis J. In the present embodiment, the first annular plastic section 24b has an approximate cylindrical shape with the central axis J as its center point. As in Fig. As shown in Figure 2, the first ring-shaped plastic section 24b opens downwards. The end of the upper side of the first ring-shaped plastic section 24b is closed by the partition section 24a.

[0024] At least a portion of the stator 20a is embedded in the first annular plastic section 24b. In the present embodiment, the entire stator 20a is embedded in the first annular plastic section 24b. The first annular plastic section 24b has a portion that covers the stator 20a radially from the inside, a portion that covers the stator 20a radially from the outside, a portion that covers the stator 20a from above, and a portion that covers the stator 20a from below. In other words, the main stator plastic section 24b has a portion that covers the stator 20a from above. In the present embodiment, the first annular plastic section 24b covers the outer surface of the stator 20a radially around its entire circumference at the central axis J.The outer surface of the stator 20a in the radial direction includes the outer surface of the stator core 21 in the radial direction and the outer surface of the insulator 22 in the radial direction. The outer surface of the stator core 21 in the radial direction is the outer surface of the core back section 21a in the radial direction.

[0025] The outer edge of the partition section 24a is radially connected to the inner edge of the first annular plastic section 24b at its end. The upper surface of the first annular plastic section 24b and the upper surface of the partition section 24a are positioned axially at the same location and are seamlessly connected. In the present embodiment, the upper surface of the stator plastic main section 24s is formed from the upper surface of the partition section 24a and the upper surface of the first annular plastic section 24b.

[0026] As in Fig. As shown in Figure 3, the first annular plastic section 24b has a large-diameter part 24c and a small-diameter part 24d. The end of the upper side of the large-diameter part 24c is the end of the upper side of the first annular plastic section 24b. The small-diameter part 24d is positioned on the lower side of the large-diameter part 24c. The end of the upper side of the small-diameter part 24d is connected to the end of the lower side of the large-diameter part 24c. The end of the lower side of the small-diameter part 24d is the end of the lower side of the first annular plastic section 24b. The outer diameter of the small-diameter part 24d is smaller than the outer diameter of the large-diameter part 24c.Between the outer surface of the large-diameter part 24c in the radial direction and the outer surface of the small-diameter part 24d in the radial direction, a downwardly directed fourth step surface 24g is provided in the axial direction. The fourth step surface 24g has a ring shape that surrounds the central axis J. More precisely, viewed in the axial direction, the fourth step surface 24g has a circular shape whose center coincides with the central axis J.

[0027] The stator plastic main section 24s has an annular groove 24f that extends from the upper surface to the underside of the stator plastic main section 24s. In the present embodiment, the annular groove 24f extends downwards from the outer edge in the radial direction of the upper surface of the stator plastic main section 24s. In the present embodiment, the annular groove 24f is provided on the upper surface of the first annular plastic section 24b, i.e., on the upper surface of the large-diameter part 24c. The annular groove 24f is located further radially inward than the outer surface of the large-diameter part 24c. The annular groove 24f has a ring shape that surrounds the central axis J. In the present embodiment, the annular groove 24f, viewed axially, has a circular shape whose center coincides with the central axis J.

[0028] The stator plastic section 24 has a concave section 24e on the outer surface of the first annular plastic section 24b, extending radially in the direction of the concave section. In the present embodiment, the concave section 24e is provided on the outer surface of the large-diameter part 24c, extending radially in the direction of the concave section. The concave section 24e extends axially from the end of the upper side of the large-diameter part 24c to the end of the lower side of the large-diameter part 24c. The concave section 24e opens axially on both sides. Multiple concave sections 24e are provided circumferentially at intervals. For example, three concave sections 24e are provided.

[0029] The stator plastic section 24 has a rib 26 that projects radially outward from the outer surface of the first annular plastic section 24b. In the present embodiment, the rib 26 projects radially outward from the outer surface of the large-diameter part 24c. The rib 26 extends axially from the end of the upper side of the large-diameter part 24c to the end of the lower side of the large-diameter part 24c. While omitted from the figures, the rib 26 is provided circumferentially in multiples at intervals. Each rib 26 is, for example, provided circumferentially in the corresponding space between circumferentially adjacent concave sections 24e in the central part.

[0030] The stator plastic section 24 has a circuit board support section 27. The circuit board support section 27 projects upwards from the upper surface of the stator plastic main section 24s. In the present embodiment, the circuit board support section 27 projects upwards from the upper surface of the first annular plastic section 24b. The circuit board support section 27 can also project upwards from the upper surface of the partition section 24a. As in Fig. As shown in Figure 2, the circuit board carrier section 27 supports the switching plate 95 from below. The circuit board carrier section 27 is fixed to the switching plate 95.

[0031] The circuit board carrier section 27 has a first part 27a and a second part 27b. The end of the lower side of the first part 27a is connected to the upper surface of the stator plastic main section 24s. As shown in Fig. As shown in Figure 3, the first part 27a has a columnar shape extending axially. The second part 27b is positioned on top of the first part 27a. The end of the lower side of the second part 27b is connected to the end of the upper side of the first part 27a. In the state before the circuit board carrier 27 is fixed to the circuit board 95, the second part 27b has an approximate columnar shape, the outer diameter of which is smaller than that of the first part 27a. As shown in Fig. As shown in Figure 2, the second part 27b is guided axially into a hole section 95a provided in the switching plate 95. A portion of the second part 27b, positioned higher than the switching plate 95, melts, for example, due to heat and is welded to the upper surface of the switching plate 95. Fig. 2 is a weld section 27c in which part of the second part 27b was melted and welded to the upper surface of the switching plate 95, indicated by a two-dot dashed line. However, part of the second part 27b does not necessarily have to be welded to the switching plate 95. As in Fig. As shown in Figure 3, the circuit board carrier section 27 is provided in multiples at intervals in the circumferential direction. In the present embodiment, three circuit board carrier sections 27 are provided.

[0032] The stator plastic section 24 has a second annular projection 25. The second annular projection 25 extends upwards from the portion that is positioned further outwards in the radial direction on the upper surface of the stator plastic main section 24s than the annular groove 24f. As shown in Fig. As shown in Figure 4, the second annular projection 25 extends upwards from the section, which is positioned further outwards in the radial direction on the upper surface of the stator plastic main section 24s than a cover tube section 61b, which is described below. As shown in Fig. As shown in Figure 3, the second annular projection 25 has a ring shape that surrounds the central axis J. In the present embodiment, the second annular projection 25, viewed axially, has a circular shape whose center coincides with the central axis J. As shown in Figure 3, the second annular projection 25 has a circular shape, the center of which coincides with the central axis J. Fig. As shown in Figure 4, the second annular projection 25 has an approximate triangular shape in a cross-sectional surface perpendicular to the circumferential direction, and is convex upwards. The second annular projection 25 is embedded in a plastic mold section 70.

[0033] As in Fig. As shown in Figure 3, the stator assembly 20 comprises conductive (e.g., electrically conductive) components 28. The conductive components 28 are made of metal. A plurality of conductive components 28 are provided at intervals around the circumference. In the present embodiment, three conductive components 28 are provided. A portion of each conductive component 28 is embedded in the stator plastic main section 24s. Each conductive component 28 is held by the stator plastic main section 24s. Each conductive component 28 projects upward from the upper surface of the stator plastic main section 24s. Each conductive component 28 has a base 28a and a terminal section 28b. A portion of the base 28a is embedded in the stator plastic main section 24s. An upper portion of the base 28a projects upward from the upper surface of the stator plastic main section 24s.This is omitted in the figures, but the portion of the base 28a embedded in the stator plastic main section 24s is electrically connected to the coil 23. The terminal section 28b projects upwards from the base 28a. Two terminal sections 28b are provided for each conductive component 28. In the present embodiment, the terminal section 28b is a press-fit connection. The terminal section 28b is pressed into the hole section 95c provided on the switching plate 95 and electrically connected to the switching plate 95. This electrically connects the coil 23 and the switching plate 95 via the conductive component 28.

[0034] As in Fig. As shown in Figure 2, the stator assembly 20 has a rotor receiving section 24r that receives the rotor 10 internally. The rotor receiving section 24r is formed by a portion of the stator plastic section 24, which radially covers the stator 20a from the inside, and the partition section 24a. The rotor receiving section 24r has a tubular shape that surrounds the central axis J and opens downwards. In the present embodiment, the rotor receiving section 24r has an approximately cylindrical shape that opens downwards, with the central axis J as its center point. The wall section, which is positioned on the top of the wall section forming the rotor receiving section 24r, is formed by the partition section 24a. The stator assembly 20 is created by overmolding the stator plastic section 24, with, for example, the stator 20a, the fixing shaft 30, and a plurality of conductive components 28 being inserted components.

[0035] A pump section 40 is connected to the underside of the rotor 10. The pump section 40 rotates about the central axis J when the rotor 10 rotates about the central axis J. The pump section 40 is made of plastic. The pump section 40 has a base section, a casing section 42, and a plurality of blades 43. In the present embodiment, the base section is connected to the end of the lower side of the second rotor plastic section 14. The second rotor plastic section 14 and the base section are parts of the same single component. The base section is created simultaneously with the second rotor plastic section 14 by overmolding. The base section has an annular shape that surrounds the central axis J. In the present embodiment, the base section has an approximate circular shape when viewed axially, with its center point coinciding with the central axis J.The outer diameter of the base section 41 is larger than the outer diameter at the lower end of the second rotor plastic section 14.

[0036] The sheathing section 42 is arranged at intervals on the underside of the base section 41. Viewed axially, the sheathing section 42 has a circular shape, the center of which coincides with the central axis J. The sheathing section 42 is, for example, separate from the base section. The plurality of blades 43 are positioned axially between the base section and the sheathing section 42. The lower end of the plurality of blades 43 is connected to the sheathing section 42. The sheathing section 42 and the plurality of blades 43 are, for example, parts of the same single component. The upper end of the plurality of blades 43 is in contact with the base section.

[0037] The switching plate 95 widens radially. The surface of the switching plate 95 is oriented axially. More precisely, the surface of the switching plate 95 is perpendicular to the axial direction. The switching plate 95 is, for example, a printed circuit board. In the present embodiment, an inverter circuit is provided on the switching plate 95, which supplies current to the coil 23. The switching plate 95 is positioned on the top surface of the stator 20a. The switching plate 95 is positioned on the top surface of the stator plastic main section 24s. The outer edge of the switching plate 95 is positioned further inward in the radial direction than the outer circumferential surface of the stator plastic main section 24s. The switching plate 95 is positioned at a distance above the upper surface of the stator plastic main section 24s.

[0038] The switching plate 95 is fixed to the stator assembly 20. In the present embodiment, the switching plate 95 is fixed to the plurality of circuit board carrier sections 27. The switching plate 95 is supported from below by the plurality of circuit board carrier sections 27. The switching plate 95 has a plurality of hole sections 95a into which the plurality of circuit board carrier sections 27 are guided axially. The outer edge of hole section 95a of the lower surface of the switching plate 95 is in contact with the upper end surface of the first section 27a. The switching plate 95 is thus supported from below by the circuit board carrier section 27. The switching plate 95 has a hole section 95b into which a second terminal section 65b, described below, is guided axially, and a hole section 95c into which the terminal section 28b is guided axially.A plurality of electronic components 96 are attached to the circuit board 95.

[0039] As in Fig. As shown in Figure 5, a housing 50 is a tubular shape that opens upwards. In the present embodiment, the housing 50 has an approximate cylindrical shape with the central axis J as its center point. The stator assembly 20 is housed inside the housing 50. The housing 50 is made of plastic. The housing 50 has a housing tube section 51 and a pump receiving section 52. The housing tube section 51 is a tubular shape that opens upwards. In the present embodiment, the housing tube section 51 has an approximate cylindrical shape with the central axis J as its center point. As shown in Figure 5, the housing tube section 51 is a tubular shape that opens upwards. Fig. As shown in Figure 2, the housing tube section 51 is positioned radially on the outside of the stator 20a. The housing tube section 51 surrounds the stator 20a radially from the outside.

[0040] As in Fig. As shown in Figure 5, the housing tube section 51 comprises a first tube section 51a, a second tube section 51b, a third tube section 51c, and a fourth tube section 51d. The first tube section 51a, the second tube section 51b, the third tube section 51c, and the fourth tube section 51d are arranged in this order from bottom to top. The end of the lower side of the first tube section 51a is the end of the lower side of the housing tube section 51.

[0041] The second pipe section 51b is positioned on the top side of the first pipe section 51a. The end of the lower side of the second pipe section 51b is connected to the end of the upper side of the first pipe section 51a. The inner diameter of the second pipe section 51b is larger than the inner diameter of the first pipe section 51a. The axial dimension of the second pipe section 51b is larger than the axial dimension of the first pipe section 51a. An upwardly directed first step surface 51e is provided in the axial direction between the inner circumferential surface of the first pipe section 51a and the inner circumferential surface of the second pipe section 51b. The first step surface 51e has an annular shape that surrounds the central axis J. In the present embodiment, the first step surface 51e, viewed in the axial direction, has a circular shape whose center coincides with the central axis J.

[0042] The third pipe section 51c is positioned on the top side of the second pipe section 51b. The end of the lower side of the third pipe section 51c is connected to the end of the upper side of the second pipe section 51b. The inner diameter of the third pipe section 51c is larger than the inner diameter of the second pipe section 51b. The axial dimension of the third pipe section 51c is smaller than the axial dimension of the first pipe section 51a. An upwardly directed second step surface 51f is provided in the axial direction between the inner circumferential surface of the second pipe section 51b and the inner circumferential surface of the third pipe section 51c. The second step surface 51f has an annular shape that surrounds the central axis J. In the present embodiment, the second step surface 51f, viewed in the axial direction, has a circular shape whose center coincides with the central axis J. As shown in Fig. As shown in Figure 4, the second step surface 51f is positioned further down than the upper surface of the stator plastic main section 24s.

[0043] The fourth tube section 51d is positioned on top of the third tube section 51c. The end of the lower side of the fourth tube section 51d is connected to the end of the upper side of the third tube section 51c. The end of the upper side of the fourth tube section 51d is the end of the upper side of the housing tube section 51. The inner diameter of the fourth tube section 51d is larger than the inner diameter of the third tube section 51c. As shown in Fig. As shown in Figure 5, the axial dimension of the fourth pipe section 51d is larger than the axial dimension of the first pipe section 51a and smaller than the axial dimension of the second pipe section 51b. An upwardly directed third step surface 51g is provided in the axial direction between the inner circumferential surface of the third pipe section 51c and the inner circumferential surface of the fourth pipe section 51d. The third step surface 51g is provided on the inner circumferential surface of the housing pipe section 51 and is an upwardly directed annular step surface that surrounds the central axis J. In the present embodiment, the third step surface 51g, viewed in the axial direction, has a circular shape whose center coincides with the central axis J. As shown in Figure 5, the third step surface 51g is circularly shaped, with its center point coinciding with the central axis J. Fig. As shown in Figure 4, the third step surface 51g is positioned higher than the upper surface of the stator plastic main section 24s. The third step surface 51g can also be positioned axially at a position equal to the upper surface of the stator plastic main section 24s, or it can be positioned lower than the upper surface of the stator plastic main section 24s.

[0044] As in Fig. As shown in Figure 2, at least part of the section positioned higher than the stator 20a from the housing tube section 51 is embedded in the plastic mold section 70. Fig. As shown in Figure 4, in the present embodiment an upper section of the third tube section 51c and the fourth tube section 51d are embedded in the plastic mold section 70. The housing tube section 51 has a first through-hole 51h in the section embedded in the plastic mold section 70, through which the housing tube section 51 penetrates from the inner circumferential surface to the outer circumferential surface. In the present embodiment, the first through-hole 51h is provided in the fourth tube section 51d. As shown in Figure 4, the housing tube section 51 has a first through-hole 51h in the fourth tube section 51d. Fig. As shown in Figure 5, the first through-hole 51h extends circumferentially. Multiple first through-holes 51h are provided at intervals circumferentially. In the present embodiment, four first through-holes 51h are provided. The inner surface of the first through-hole 51h has an upward-facing surface, a downward-facing surface, a surface facing circumferentially to one side, and a surface facing circumferentially to the other side.

[0045] The housing tube section 51 has a through-hole section 51i that penetrates the housing tube section 51 from the inner circumferential surface to the outer circumferential surface. The through-hole section 51i is provided in the fourth tube section 51d. The through-hole section 51i opens upwards. The through-hole section 51i is provided in the corresponding space between the first through-holes 51h, which are adjacent to each other at intervals in the circumferential direction.

[0046] As in Fig. As shown in Figure 2, the stator assembly 20 is positioned radially on the inside of the housing tube section 51. The first annular plastic section 24b is fitted radially on the inside of the housing tube section 51. Therefore, the position of the stator 20a radially relative to the housing 50 can be determined via the stator plastic section 24. In the present embodiment, the large-diameter part 24c, located on the first annular plastic section 24b, is fitted into the inside of the second tube section 51, which is located within the housing tube section 51. In the present embodiment, the first annular plastic section 24b is pressed radially towards the inside of the housing tube section 51 when the rib 26 is in contact with the inner circumferential surface of the housing tube section 51.When the stator assembly 20 is fitted radially into the inner surface of the first annular plastic section 24, the rib 26 is elastically deformed radially. The rib 26 is in contact with the inner circumferential surface of the second tube section 51b.

[0047] Furthermore, the rib 26 is not limited to being provided on the stator plastic section 24, but can also be provided on the housing 50. For example, the rib 26 can also be provided on a convex section 55 of the housing 50 as described below. If the rib 26 is provided on the convex section 55, the rib 26 can, for example, project radially from the inner surface of the convex section 55 towards the inner surface and extend axially. When the rib 26 is provided on the convex section 55, the rib 26 is in radial contact with the outer surface of the concave section 24e of the stator plastic section 24 and is in a radially elastically deformed state. This allows the stator assembly 20 to be pressed radially against the inner surface of the housing tube section 51 when the stator assembly 20 is mounted on the housing tube section 51.If the rib 26 is provided on the housing 50, the rib 26 can also be provided at a location on the inner circumferential surface of the housing tube section 51 that is offset circumferentially from the location where the convex section 55 described below is provided.

[0048] The fourth stepped surface 24g, located on the outer circumferential surface of the stator plastic main section 24s, contacts the first stepped surface 51, located on the inner circumferential surface of the housing tube section 51, from above. This allows the axial position of the stator plastic main section 24 relative to the housing 50 and the axial position of the stator 20a relative to the housing 50 to be determined. The small-diameter portion 24d on the first annular plastic section 24b is positioned radially on the inner side of the first tube section 51a. The outer circumferential surface of the small-diameter portion 24d is radially spaced on the inner side of the inner circumferential surface of the first tube section 51a.The end on the outside on the lower surface of the first annular plastic section 24b in the radial direction is positioned over a gap on the top of an annular wall section 52b of the pump receiving section 52 described below.

[0049] As in Fig. As shown in Figure 4, the inner circumferential surface of the third tube section 51c on the housing tube section 51 is an inner circumferential surface section 51k, which is provided radially spaced from the outer circumferential surface of the first annular plastic section 24b. In other words, the inner circumferential surface of the housing tube section 51 has an inner circumferential surface section 51k. The inner circumferential surface section 51k is located further up than the portion of the inner circumferential surface of the housing tube section 51 to which the first annular plastic section 24b is fitted, in other words, the inner circumferential surface of the second tube section 51b. The inner circumferential surface section 51k is positioned further on the outer side in the radial direction than the inner circumferential surface of the second tube section 51b. The inner circumferential surface section 51k is positioned further on the inner side in the radial direction than the inner circumferential surface of the fourth tube section 51d.The inner circumferential surface section 51k, the second step surface 51f, and the outer circumferential surface of the first annular plastic section 24b form an annular groove 51m, which opens upwards and surrounds the central axis J. The second step surface 51f is the groove base surface of the groove 51m.

[0050] As in Fig. As shown in Figure 2, the pump receiving section 52 is positioned on the underside of the casing tube section 51. The pump receiving section 52 is connected to the end of the lower side of the casing tube section 51. The axial dimension of the pump receiving section 52 is smaller than the axial dimension of the casing tube section 51. The pump receiving section 52 accommodates the pump section 40 internally. The interior of the pump receiving section 52 is connected to the interior of the rotor receiving section 24r. The pump receiving section 52 has an annular bottom wall section 52a that surrounds the central axis J, and an annular wall section 52b that projects radially upward from the outer edge of the bottom wall section 52a. The bottom wall section 52a is positioned on the lower side of the pump section 40.The end on the outside of the bottom wall section 52a, in the radial direction, is positioned further outwards in the radial direction than the pump section 40. The annular wall section 52b has a ring shape that surrounds the central axis J and opens upwards. The inner diameter of the annular wall section 52b is smaller than the inner diameter of the casing tube section 51. The outer radial edge at the end of the upper side of the annular wall section 52b is connected to the end of the lower side of the casing tube section 51. The annular wall section 52b is positioned radially on the outside of the pump section 40. The annular wall section 52b surrounds the pump section 40.

[0051] The pump inlet section 52 has a flow path section 52c. The flow path section 52c is positioned radially on the outside of the pump section 40. The flow path section 52c is positioned radially between the pump section 40 and the annular wall section 52b. Although it is omitted from the figures, the flow path section 52c extends circumferentially.

[0052] The housing 50 has an intake opening section 53. The intake opening section 53 projects radially downwards from the inner edge of the bottom wall section 52a. In the present embodiment, the intake opening section 53 has an approximate cylindrical shape with the central axis J as its center point. The intake opening section 53 opens downwards. The interior of the intake opening section 53 is connected to the interior of the pump receiving section 52.

[0053] When the rotor 10 rotates and the pump section 40 rotates, water is drawn from the intake opening section 53 into the interior of the pump receiving section 52. At least some of the water drawn into the pump receiving section 52 is drawn radially from the inside of the casing section 42 into the interior of the pump section 40. The water drawn into the pump section 40 is expelled radially to the outside, flows along the flow path section 52c, and is discharged from an outlet opening section (not shown) to the outside of the electric pump 100. Furthermore, some of the water drawn in by the intake opening section 53 also flows, for example, into the interior of the rotor receiving section 24r.

[0054] The housing 50 has a rotor support section 57 that supports the rotor 10 from below. The rotor support section 57 has a main support section 57a ​​and a plurality of feet 57b. The main support section 57a ​​supports the rotor 10 from below via a washer 32. The fixing shaft 30 is guided axially on the inside of the washer 32. The washer 32 is in contact with its end on the upper side of the main support section 57a ​​and its end on the lower side of the bearing 15. The plurality of feet 57b extend upwards from the inner circumferential surface of the intake opening section 53. The upper end of the plurality of feet 57b is connected to the main support section 57a.

[0055] As in Fig. As shown in Figure 5, the housing 50 has a first annular projection 54. The first annular projection 54 projects upwards from the third step surface 51g. The first annular projection 54 has a ring shape that surrounds the central axis J. In the present embodiment, the first annular projection 54 has a circular shape when viewed axially, the center of which coincides with the central axis J. As shown in Fig. As shown in Figure 4, the first annular projection 54 has an approximate triangular shape in a cross-sectional area perpendicular to the circumferential direction, and is convex upwards. The first annular projection 54 is embedded in the plastic mold section 70. The upper end of the first annular projection 54 is positioned further down than the first through-hole 51h. The first annular projection 54 is positioned further up than the second annular projection 25.

[0056] As in Fig. As shown in Figure 5, the housing 50 has a convex section 55 that projects radially from the inner circumferential surface of the housing tube section 51 to the inside. In the present embodiment, the convex section 55 projects radially from the inner circumferential surface of the second tube section 51b to the inside. The convex section 55 extends axially. The lower end of the convex section 55 is connected to the first step surface 51e. The upper end of the convex section 55 is positioned further down than the upper end of the inner circumferential surface of the second tube section 51b. The inner surface of the convex section 55 is positioned further out radially than the inner circumferential surface of the first tube section 51a. The convex section 55 is provided in multiples at intervals around the circumference. For example, three convex sections 55 are provided. As shown in Figure 5, the convex section 55 is positioned further out radially than the inner circumferential surface of the first tube section 51a. Fig. As shown in Figure 2, a convex section 55 is fitted into a concave section 24e. This allows the circumferential position of the stator assembly 20 relative to the housing 50 to be determined. As mentioned above, if a rib 26 is provided on the convex section 55, and the rib 26 is in radial contact with the outer surface of the concave section 24e, and the stator assembly 20 presses radially against the inner surface of the housing tube section 51, the circumferential position of the stator assembly 20 relative to the housing 50 can be determined by fitting the convex section 55 into the interior of the concave section 24e.

[0057] As in Fig. As shown in Figure 5, the housing 50 has a plurality of mounting sections 56 that project radially outwards from the housing tube section 51. The plurality of mounting sections 56 are arranged at intervals in the circumferential direction. The plurality of mounting sections 56 are parts that are attached to machines to which the electric pump 100 is mounted. Each mounting section 56 is fastened to a machine to which the electric pump 100 is mounted, for example, by a screw that penetrates each mounting section 56 axially.

[0058] As in Fig. As shown in Figure 2, a cover assembly 60 is positioned on the top of the stator assembly 20. The cover assembly 60 comprises a cover 61, a connector section 62, and a connector terminal 65. The cover 61 and the connector section 62 are made of plastic. In the present embodiment, the cover 61 and the connector section 62 are sections of the same single component. The cover 61 and the connector section 62 are manufactured, for example, by overmolding the connector terminal 65 as an insert element.

[0059] The cover 61 covers the switching plate 95 from above. The cover 61 is positioned radially on the inside of the housing tube section 51. The cover 61 has a lid section 61a and a cover tube section 61b. The lid section 61a is positioned on the top of the switching plate 95. The lid section 61a covers the switching plate 95 from above. The lid section 61a widens radially. In the present embodiment, the lid section 61a is plate-shaped, with the plate surface oriented axially. The lid section 61a clamps the switching plate 95 in the space between it and the stator plastic main section 24s in the axial direction. In other words, the switching plate 95 is positioned in the axial space between the stator plastic main section 24s and the lid section 61a. The lid section 61a is provided spaced apart on the top of the switching plate 95. As in Fig. As shown in Figure 6, the cover section 61a in the present embodiment has a circular shape when viewed axially, the center of which coincides with the central axis J. As shown in Figure 6, the cover section 61a in the present embodiment has a circular shape when viewed in the axial direction, the center of which coincides with the central axis J. Fig. As shown in Figure 4, the upper surface of the cover section 61a is provided in the axial direction at the same position as the upper end of the housing tube section 51. In other words, the upper surface of the cover section 61a is provided in the axial direction at the same position as the upper end of the housing tube section 51.

[0060] The cover tube section 61b projects downwards from the cover section 61a. In the present embodiment, the cover tube section 61b projects radially downwards from the outer edge portion of the cover section 61a. The cover tube section 61b is a tube that opens downwards. In the present embodiment, the cover tube section 61b has a cylindrical shape with the central axis J as its center point. The cover tube section 61b is positioned radially on the outside of the switching plate 95. The cover tube section 61b surrounds the switching plate 95. At least a portion of the cover tube section 61b is positioned radially on the inside of the housing tube section 51. In the present embodiment, the entirety of the cover tube section 61b is positioned radially on the inside of the housing tube section 51.The cover tube section 61b is positioned radially on the inside of the third tube section 51c and the fourth tube section 51d. The outer circumferential surface of the cover tube section 61b is provided radially away from the inner circumferential surface of the housing tube section 51 on the inside.

[0061] The lower end of the cover tube section 61b is fitted into the interior of the annular groove 24f. Therefore, it is possible to determine the radial position of the cover 61 relative to the stator plastic main section 24s. In the present embodiment, the lower end of the cover tube section 61b has a clearance fit inside the annular groove 24f. The lower end of the cover tube section 61b can also be pressed into the interior of the annular groove 24f. The lower end of the cover tube section 61b contacts the stator plastic main section 24s from above. In the present embodiment, the lower end of the cover tube section 61b contacts the groove bottom surface, which is positioned on the lower side of the inner surface of the annular groove 24f, from above.

[0062] The lower opening of the cover 61, i.e., the lower opening of the cover tube section 61b, is closed by the stator plastic main section 24s. The cover 61 and the stator plastic main section 24s together form the circuit board mounting section 90, which accommodates the switching plate 95 inside.

[0063] The cover 61 has a third annular projection 63 that extends upwards from the upper surface of the cover section 61a. In the present embodiment, the third annular projection 63 is provided on the outer section in the radial direction of the upper surface of the cover section 61a. As shown in Fig. As shown in Figure 6, the third annular projection 63 is ring-shaped and surrounds the central axis J. In the present embodiment, the third annular projection 63, viewed axially, has a circular shape whose center coincides with the central axis J. In the present embodiment, the third annular projection 63 is provided in multiples at radial intervals. In the present embodiment, two third annular projections 63 are provided, i.e., a third annular projection 63a and a third annular projection 63b. The outer diameter of the third annular projection 63b is larger than the outer diameter of the third annular projection 63a. The third annular projection 63b is arranged radially at a distance on the outside of the third annular projection 63a. The third annular projection 63b surrounds the third annular projection 63a. As shown in Figure 6, the third annular projection 63b is arranged at a radial distance. Fig. As shown in Figure 4, the third annular projection 63 has an approximate triangular shape in a cross-sectional surface perpendicular to the circumferential direction, and is convex upwards. The third annular projection 63 is embedded in the plastic mold section 70.

[0064] As in Fig. As shown in Figure 7, when the plastic mold section 70 is formed, the tip section 63c of the third annular projection 63 is melted by the molten plastic poured into the die and mixed with the plastic forming the plastic mold section 70. The tip section 63c is melted and acquires an irregular shape, and the boundary between the tip section 63c and the plastic mold section 70 is irregular and acquires a complex shape. This is omitted from the figures, but the tip section of the first annular projection 54 and the tip section of the second annular projection 25 are melted and mixed with the plastic forming the plastic mold section 70 in the same way as the tip section 63c of the third annular projection 63.

[0065] As in Fig. As shown in Figure 6, the connector section 62 projects radially from the cover 61 to the outside. More precisely, the connector section 62 projects radially from the outer circumferential surface of the cover tube section 61b to the outside. The connector section 62 has a connector base 62a and a connector tube section 62b. The connector base 62a projects radially from the cover 61 to the outside. The connector base 62a has an approximate cuboid shape. As shown in Fig. As shown in Figure 2, the connector base 62a is guided radially towards the through-hole section 51i. The outer end of the connector base 62a, in the radial direction, is positioned at the outer section of the housing tube section 51.

[0066] The connector tube section 62b is radially connected to the outer end of the connector base 62a. The connector tube section 62b has a tubular shape that opens radially outwards. As shown in Fig. As shown in Figure 6, the plug tube section 62b has an approximately rectangular tube shape. The axial dimension of the plug tube section 62b is greater than the axial dimension of the plug base 62a. The circumferential dimension of the plug tube section 62b is greater than the circumferential dimension of the plug base 62a.

[0067] The 65 connector is a metal component. As in Fig. As shown in Figure 2, a section of the connector terminal 65 is embedded in the connector section 62. This section of the connector terminal 65 is embedded radially into the connector base 62a and into the bottom section on the inside of the connector tube section 62b. In the present embodiment, another section of the connector terminal 65 is embedded in the cover section 61a. The connector terminal 65 has a first terminal section 65a and a second terminal section 65b. The first terminal section 65a projects radially from the bottom section on the inside of the connector tube section 62b. The first terminal section 65a is free within the interior of the connector tube section 62b. The second terminal section 65b projects downwards from the lower surface of the cover section 61a. The second terminal section 65b is pressed into the hole section 95c provided on the switching plate 95 and electrically connected to the switching plate 95.The second connection section 65b is, for example, a press-fit connection. The end on the outside of the first connection section 65a in the radial direction is one end of the connector 65. The lower end of the second connection section 65a is the other end of the connector 65. In the present embodiment, the entire connector 65, except for the first connection section 65a and the second connection section 65b, is embedded in the connector section 62.

[0068] An external power source (not shown in the figures) is connected to the plug section 62. The external power source is electrically connected to the first connection section 65a, which is exposed inside the plug tube section 62b. Current from the external power source is supplied to the switching plate 95 via the plug terminal 65. A portion of the current supplied to the switching plate 95 is fed to the coil 23 via the conductive components 28.

[0069] As in Fig. As shown in Figure 6, the connector section 62 has a fourth annular projection 64. The fourth annular projection 64 is provided on the outer surface of the connector base 62a. The fourth annular projection 64 has a ring shape that surrounds the connector base 62a around the axis extending in the radial direction in which the connector section 62 projects. In the present embodiment, the fourth annular projection 64, viewed from the radial direction in which the connector section 62 projects, has a rectangular frame shape. In the present embodiment, a plurality of fourth annular projections 64 are provided spaced apart in the radial direction in which the connector section 62 projects. In the present embodiment, two fourth annular projections 64, i.e., a fourth annular projection 64a and a fourth annular projection 64b, are provided.The fourth annular projection 64b is provided radially spaced outwards from the fourth annular projection 64a. As in . Fig. As shown in Figure 2, the fourth annular projection 64 has an approximate triangular shape in a cross-sectional area perpendicular to the extension direction of the fourth annular projection 64, which is convex in a direction away from the outer surface of the connector base 62a. The fourth annular projection 64 is embedded in the plastic mold section 70. This is omitted in the figures, but the tip section of the fourth annular projection 64 is formed in the same way as shown in Figure 2. Fig. 7 The tip section 63c of the third annular projection 63 shown is melted and mixed with the plastic that forms the plastic mold section 70.

[0070] The plastic mold section 70 is made of plastic. The plastic mold section 70 is manufactured by overmolding, with an assembly 100b in which parts of the electric pump 100 other than the plastic mold section 70 are assembled (see Fig. 11), serves as an operational element. As in Fig. As shown in Figure 1, the plastic mold section 70 is positioned at the upper end of the electric pump 100. In the present embodiment, the plastic mold section 70 has a ring shape that surrounds the central axis J. More precisely, viewed axially, the plastic mold section 70 has an approximate circular shape, the center of which coincides with the central axis J. As shown in Figure 1, the plastic mold section 70 is positioned at the upper end of the electric pump 100. Fig. As shown in Figure 2, the plastic mold section 70 is in contact with at least a part of the housing 50 and at least a part of the cover 61, joining the housing 50 and the cover 61. Therefore, a worker or similar person manufacturing the electric pump 100 can join the housing 50 and the cover 61 by molding the plastic mold section 70 using a die. This reduces, for example, the labor hours and assembly time of the electric pump 100 compared to a case where the cover 61 and the pump mounting section 52 are individually fixed to the stator plastic section 24 by welding or similar methods. Accordingly, the labor hours and time required to manufacture the electric pump 100 can be reduced.

[0071] Furthermore, in this disclosure, “workers and the like” includes a worker and an assembly device, etc., which perform a respective operation. Each operation can be performed by only one worker, only by an assembly device, or by one worker and an assembly device.

[0072] As in Fig. As shown in Figure 1, the plastic mold section 70 has a plastic lid section 71 and a second annular plastic section 72. The plastic lid section 71 is a section that is in contact with the upper surface of the lid section 61a. The plastic lid section 71 has an annular shape that surrounds the central axis J. In the present embodiment, the plastic lid section 71 has an approximate circular shape in the axial direction, the center of which coincides with the central axis J. In the present embodiment, the plastic lid section 71 contacts an outer section of the upper surface of the lid section 61a in the radial direction. The upper surface of the plastic lid section 71 is the upper surface of the plastic mold section 70.

[0073] The second annular plastic section 72 projects radially downwards from the outer edge of the plastic cover section 71. The second annular plastic section 72 has a ring shape that surrounds the central axis J. In the present embodiment, the second annular plastic section 72 has an approximate circular shape when viewed axially, the center of which coincides with the central axis J. As in Fig. As shown in Figure 2, the second annular plastic section 72 is positioned radially on the outer side of the cover tube section 61b. The second annular plastic section 72 surrounds the cover tube section 61b. In the present embodiment, the lower end of the second annular plastic section 72 is positioned further up than the upper end of the stator 20a. The outer circumferential surface of the second annular plastic section 72 is positioned further out radially than the outer circumferential surface of the fourth tube section 51d. The axial dimension of the second annular plastic section 72 is less than half the axial dimension of the housing tube section 51.

[0074] The second annular plastic section 72 fills the space between the housing tube section 51 and the cover tube section 61b in the radial direction over a complete revolution around the central axis J. In other words, the plastic mold section 70 fills the gap between the housing 50 and the cover 61 over a complete revolution around the central axis J. Therefore, by forming the plastic mold section 70, the housing 50 and the cover 61 can be joined, and at the same time, the gap between the housing 50 and the cover 61 can be filled. Accordingly, the plastic mold section 70 prevents foreign material, such as liquids, etc., from entering the gap between the housing 50 and the cover 61 from the outside of the electric pump 100.Furthermore, by filling the gap between the housing 50 and the cover 61 over a complete circumnavigation of the central axis J with the plastic mold section 70, the housing 50 and the cover 61 can be more firmly connected via the plastic mold section 70.

[0075] As in Fig. As shown in Figure 4, the second annular plastic section 72 is in contact with the entire outer circumferential surface of the section of the cover tube section 61b, except for the section in which the annular groove 24f is located. The second annular plastic section 72 has a portion positioned radially between the outer circumferential surface of the cover tube section 61b and the inner circumferential surface of the housing tube section 51, a portion positioned radially on the outside of the housing tube section 51, and a portion positioned inside the first through-hole 51h. The lower end of the portion of the second annular plastic section 72 that is positioned radially on the outside of the housing tube section 51 is positioned further down than the upper surface of the stator plastic main section 24s and further up than the second step surface 51f.Furthermore, the lower end of the part of the second annular plastic section 72, which is positioned radially on the outside of the housing tube section 51, can also be provided at a position that is equal to the upper surface of the stator plastic main section 24s in the axial direction and can be positioned further up than the upper surface of the stator plastic main section 24s.

[0076] As in Fig. As shown in Figure 2, an upper end of the portion of the second annular plastic section 72, which is positioned radially between the outer circumferential surface of the cover tube section 61b and the inner circumferential surface of the housing tube section 51, is positioned higher than the first connection section 65a. A lower end of the portion of the second annular plastic section 72, which is positioned radially between the outer circumferential surface of the cover tube section 61b and the inner circumferential surface of the housing tube section 51, is positioned lower than the first connection section 65a. In other words, the portion of the plastic mold section 70, which is positioned radially between the outer circumferential surface of the cover tube section 61b and the inner circumferential surface of the housing tube section 51, has a part that is provided in the axial direction at the same position as the first connection section 65a.This prevents the connection between the housing 50 and the cover 61 from being disconnected, even if a radial load is applied to the connector section 62 when connecting and disconnecting the external power source at the connector section 62.

[0077] As in Fig. As shown in Figure 4, the second annular plastic section 72 is in contact with at least a portion of the housing tube section 51. The second annular plastic section 72 is in contact with at least a portion of the section of the housing tube section 51 that is positioned higher than the stator 20a. In other words, at least a portion of the part of the housing tube section 51 that is positioned higher than the stator 20a is in contact with the plastic mold section 70. The plastic mold section 70 connects the housing tube section 51 and the cover 61. Compared to the pump mounting section 52, the housing tube section 51 is positioned axially closer to the cover 61 in order to surround the stator 20a radially from the outside.Therefore, the axial dimension of the plastic mold section 70 can be reduced compared to the case where the pump mounting section 52 and the cover 61 are connected by the plastic mold section 70, due to the connection of the housing tube section 51 and the cover 61 by the plastic mold section 70. This reduces the amount of plastic required for molding the plastic mold section 70. Consequently, when molding the plastic mold section 70, the amount of molten plastic poured into the die can be reduced, and the amount of heat transferred from the molten plastic to the assembly 100b in the die can be reduced. This prevents the temperature of the switching plate 95 and the temperature of the rotor 10 from increasing during the molding of the plastic mold section 70.Accordingly, when shaping the plastic mold section 70, it is possible to prevent the switching plate 95 from being damaged by heat and the magnets 12 on the rotor 10 from being demagnetized by heat. Furthermore, by reducing the axial dimension of the plastic mold section 70, it is possible to prevent sink marks from forming as easily during the molding process. Additionally, by reducing the axial dimension of the plastic mold section 70, it is easier to miniaturize the electric pump 100.

[0078] In the second annular plastic section 72, at least a portion of the housing tube section 51 positioned higher than the stator 20a is embedded. In other words, at least a portion of the housing tube section 51 positioned higher than the stator 20a is embedded in the plastic mold section 70. This allows the housing 50 and the plastic mold section 70 to be fixed more securely. The housing tube section 51 has a first through-hole 51h in the section embedded in the plastic mold section 70, which penetrates the housing tube section 51 from the inner circumferential surface to the outer circumferential surface. This allows a portion of the plastic mold section 70 to be positioned in the first through-hole 51h, and it is possible to ensure that the plastic mold section 70 comes into contact with the inner surface of the first through-hole 51h.This increases the contact area between the plastic mold section 70 and the housing 50, allowing them to be more securely fixed. Furthermore, because the plastic mold section 70 engages with the surface positioned at the top of the inner surface of the first through-hole 51h, it prevents the plastic mold section 70 from disengaging from the housing 50, even when subjected to an upward force. Additionally, because the plastic mold section 70 engages with the circumferentially oriented surface of the inner surface of the first through-hole 51h, it prevents the plastic mold section 70 from rotating (idling) relative to the housing 50, even when subjected to a circumferentially oriented force.

[0079] As in Fig. As shown in Figure 2, the first through-hole 51h has a portion that is provided in the axial direction at the same position as the first connection section 65a. This better prevents the connection between the housing 50 and the cover 61 from becoming loose, even when a radial load is applied to the connector section 62 during connection and disconnection of the external power source.

[0080] In the present embodiment, the second annular plastic section 72 connects the housing tube section 51 and the cover tube section 61b, at least a portion of which is positioned radially on the inside of the housing tube section 51. In other words, the plastic mold section 70 connects the housing tube section 51 and the cover tube section 61b. By enabling the housing tube section 51 and the cover tube section 61b, in which at least a portion of each overlaps radially, to be connected by the plastic mold section 70, the housing 50 and the cover 61 can be more securely joined.

[0081] In the present embodiment, the second annular plastic section 72 is in contact with almost the entire surface of the section of the housing tube section 51 that is positioned higher than the stator 20a. The second annular plastic section 72 is in contact with the inner circumferential surface in the upper part of the third tube section 51c, the outer circumferential surface of the upper part of the third tube section 51c, the inner circumferential surface of the fourth tube section 51d, the outer circumferential surface of the fourth tube section 51d, the third step surface 51g, the inner surface of the first through-hole 51h, and the upper end surface of the housing tube section 51.

[0082] As in Fig. As shown in Figure 4, in the present embodiment, the plastic mold section 70 is in contact with the outer circumferential surface of the cover tube section 61b, the inner circumferential surface of the housing tube section 51, the outer circumferential surface of the housing tube section 51, the upper surface of the cover section 61a, and the upper end surface of the housing tube section 51 via the plastic cover section 71 and the second annular plastic section 72. This increases the contact area between the plastic mold section 70 and the housing 50, as well as between the plastic mold section 70 and the cover 61. Furthermore, the plastic mold section 70 can be in contact with both the radially oriented surface and the axially oriented surface of the housing 50 and the cover 61. This allows the housing 50 and the cover 61 to be more firmly connected via the plastic mold section 70.

[0083] In the present embodiment, the upper end of the housing tube section 51 is positioned axially in the same position as the upper surface of the cover section 61a. This allows the poured plastic to flow more easily to the top of the housing tube section 51 when the plastic mold section 70 is poured from the top of the cover section 61a into the die, compared to when the upper end of the housing tube section 51 is positioned higher than the upper surface of the cover section 61a. This simplifies the production of the plastic mold section 70 and facilitates the embedding of part of the housing tube section 51 within the plastic mold section 70. Furthermore, the upper end of the housing tube section 51 can also be positioned axially lower than the surface on the opposite side of the cover section 61a.Even in this case, if, during the forming of the plastic mold section 70, plastic is poured into the die from the top of the cover section 61a, it can be achieved that the cast plastic flows more easily to the top of the housing tube section 51.

[0084] The first annular projection 54, provided on the housing 50, is embedded in the plastic mold section 70. In the present embodiment, the first annular projection 54 is embedded in the second annular plastic section 72. As the plastic mold section 70 is formed, a portion of the first annular projection 54 melts through the molten plastic poured into the die and mixes with the plastic forming the plastic mold section 70. Specifically, as mentioned above, the tip portion of the first annular projection 54 melts in the same way as the portion embedded in the second annular plastic section 72. Fig. The tip section 63c of the third annular projection 63, shown in Figure 7, acquires an irregular shape and mixes with the plastic that forms the plastic mold section 70. This gives the boundary between the first annular projection 54 and the plastic mold section 70 a complex shape, thus preventing liquids, etc., from passing through this boundary. Therefore, even if, for example, a liquid enters at the boundary between the second annular plastic section 72 and the housing 50, the liquid can be contained at the boundary between the first annular projection 54 and the plastic mold section 70.Accordingly, by providing the first annular projection 54, which is embedded in the plastic mold section 70, on the housing 50, the space between the housing 50 and the plastic mold section 70 can be appropriately sealed. Specifically, with this embodiment, even if water flowing on the flow path section 52c enters at the interface between the stator plastic section 24 and the housing tube section 51, the water can be contained at the interface between the first annular projection 54 and the second annular plastic section 72.This prevents water from flowing into the boundary between the outer circumferential surface of the housing tube section 51 and the second annular plastic section 72, and prevents water from leaking from the boundary between the lower end of the second annular plastic section 72 and the housing tube section 51 to the outside of the electric pump 100.

[0085] As in Fig. As shown in Figure 4, in the present embodiment, the plastic mold section 70 is in contact with at least a portion of the stator plastic section 24 and connects the housing 50, the cover 61, and the stator plastic section 24. Therefore, it is possible to connect the stator plastic section 24 to the housing 50 and the cover 61 by molding the plastic mold section 70. This allows a worker, or similar person, to fix the stator plastic section 24, into which at least a portion of the stator 20a is embedded, by simply molding the plastic mold section 70, without having to specifically perform the process of fixing the stator plastic section 24. Accordingly, the labor hours and the time required to manufacture the electric pump 100 can be reduced.

[0086] In the present embodiment, the lower end of the cover tube section 61b contacts the stator plastic main section 24s from above. This prevents molten plastic from entering the interior of the cover tube section 61b from the space between the lower end of the cover tube section 61b and the stator plastic main section 24s during the molding of the plastic mold section 70. This also better prevents heat from being transferred from the molten plastic to the switching plate 95 during the molding process, and thus better prevents the temperature of the switching plate 95 from rising. Consequently, it also better prevents the switching plate 95 from being damaged by heat.Furthermore, during the forming of the plastic mold section 70, as molten plastic flows from the top of the cover 61 into the die, it is possible to press the lower end of the cover tube section 61b into the stator plastic main section 24s from above through the molten plastic. This makes it possible to more effectively prevent molten plastic from entering the interior of the cover tube section 61b from the space between the lower end of the cover tube section 61b and the stator plastic main section 24s.

[0087] In the present embodiment, the lower end of the cover tube section 61b is fitted into the interior of the annular groove 24f. This makes it easy to increase the contact area between the lower end of the cover tube section 61b and the stator plastic main section 24s. This allows the annular groove 24b to more effectively prevent plastic from passing through the gap between the cover tube section 61b and the stator plastic main section 24s during the molding of the plastic mold section 70. Similarly, it allows the annular groove 24b to more effectively prevent molten plastic from entering the interior of the cover tube section 61b from the gap between the lower end of the cover tube section 61b and the stator plastic main section 24s during the molding of the plastic mold section 70.Accordingly, it is possible to suppress, in a more suitable way, the damage to the switching plate 95 caused by heat.

[0088] In its present form, the plastic mold section 70 has a filling section 73 that fills the radially oriented gap between the inner circumferential surface section 51k and the outer circumferential surface of the first annular plastic section 24b. This makes it possible to press the stator plastic section 24 down radially from the outside by means of the filling section 73. Accordingly, the stator plastic section 24 can be more firmly fixed by the plastic mold section 70. The filling section 73 is located inside the groove 51m. The filling section 73 has an annular shape that surrounds the central axis J. The filling section 73 is in contact with the inner circumferential surface section 51k and the outer circumferential surface of the first annular plastic section 24b.

[0089] The plastic mold section 70 is in contact with the second annular plastic section 72, which is positioned further out radially on the upper surface of the stator plastic main section 24s than a cover tube section 61b. The plastic mold section 70 is in contact with the filling section 73, which encompasses the upper end on the outer circumferential surface of the large-diameter part 24c of the stator plastic main section 24s. In other words, the plastic mold section 70 is in contact with the upper surface of the stator plastic main section 24s and with the outer radial surface of the stator plastic main section 24s. This increases the contact area between the plastic mold section 70 and the stator plastic main section 24. This allows the stator plastic section 24, the housing 50, and the cover 61 to be more firmly connected via the plastic mold section 70.

[0090] The second annular projection 25, provided on the stator plastic section 24, is embedded in the plastic mold section 70. In the present embodiment, the second annular projection 25 is embedded in the second annular plastic section 72. As the plastic mold section 70 is formed, a portion of the second annular projection 25 melts through the molten plastic poured into the die and mixes with the plastic forming the plastic mold section 70. Specifically, as mentioned above, the tip portion of the second annular projection 25 melts in the same way as the portion embedded in the plastic section 72. Fig. The tip section 63c of the third annular projection 63, shown in Figure 7, acquires an irregular shape and mixes with the plastic that forms the plastic mold section 70. This gives the boundary between the second annular projection 25 and the plastic mold section 70 a plurality of shapes, thus preventing liquids, etc., from passing through the boundary between the second annular projection 25 and the plastic mold section 70. This allows the liquid to be contained at the boundary between the second annular projection 25 and the plastic mold section 70, even if, for example, a liquid enters at the boundary between the second annular plastic section 72 and the stator plastic section 24.Accordingly, by providing the second annular projection 25, which is embedded in the plastic mold section 70, on the stator plastic section 24, the space between the stator plastic section 24 and the plastic mold section 70 can be appropriately sealed. Specifically, with this embodiment, even if flowing water enters the flow path section 52 at the interface between the stator plastic section 24 and the housing 51, the water can be contained at the interface between the second annular projection 25 and the second annular plastic section 72.This prevents water from flowing into the boundary between the cover tube section 61b and the second annular plastic section 72, and prevents water from flowing from the boundary between the cover tube section 61b and the second annular plastic section 72 into the interior of the circuit board receiving section 90.

[0091] As in Fig. As shown in Figure 7, a third annular projection 63, provided on the cover 61, is embedded in the plastic mold section 70. In the present embodiment, the third annular projection 63 is embedded in the second plastic cover section 71. When the plastic mold section 70 is formed, part of the third annular projection 63 melts through the molten plastic poured into the die and mixes with the plastic forming the plastic mold section 70. Specifically, as mentioned above, the tip section 63c of the third annular projection 63 melts, acquires an irregular shape, and mixes with the plastic forming the plastic mold section 70. This gives the boundary between the third annular projection 63 and the plastic mold section 70 a plurality of shapes, and it can suppress the ingress of liquids, etc.at the boundary between the third annular projection 63 and the plastic mold section 70. This allows, even if, for example, a liquid enters at the boundary between the plastic lid section 71 and the lid section 61a, the liquid to be contained at the boundary between the third annular projection 63 and the plastic lid section of the plastic mold section 70. Similarly, by providing the third annular projection 63, which is embedded in the plastic mold section 70, on the upper surface of the lid section 61a, the space between the plastic lid section 71 and the lid section 61a can be appropriately sealed.Specifically, with this embodiment, even if liquid enters from the outside of the electric pump 100 at the boundary between the inner edge in the radial direction of the plastic cover section 71 and the cover section 61a, the liquid can be contained at the boundary between the third annular projection 63 and the plastic cover section 71. This prevents liquid from flowing into the boundary between the outer circumferential surface of the cover tube section 61b and the second annular plastic section 72, and it also prevents liquid from flowing from the boundary between the cover tube section 61b and the inner surface of the annular groove 24f into the interior of the circuit board receiving section 90.

[0092] In the present embodiment, the third annular projection 63 is provided in multiples at intervals in the radial direction. This prevents liquid from passing over the other boundary of the third annular projection 63 and the plastic mold section 70, even if it passes over one boundary. This improves the seal between the plastic cover section 71 and the cover section 61a.

[0093] As in Fig. As shown in Figure 1, sprue gates 71 are provided on the upper surface of the plastic mold section 70. In the present embodiment, the sprue gates 71a are provided on the inner edge in the radial direction of the upper surface of the plastic lid section 71. A plurality of sprue gates 71a are provided at intervals in the circumferential direction. The number of sprue gates 71a is not particularly limited, provided it is at least 1. The sprue gates 71a are markings that are created during the molding of the plastic mold section 70 by providing gates through which plastic is poured into the die. The sprue gates 71a project, for example, slightly upwards from the upper surface of the plastic lid section 71. The sprue gates 71a are, for example, circular when viewed axially.Since the sprue gates 71a are provided on the upper surface of the plastic mold section 70, the plastic can flow from above during the molding of the plastic mold section 70, and the cover 61 can be pressed onto the stator plastic main section 24s by the plastic. This, as mentioned above, appropriately prevents plastic from entering the interior of the circuit board receiving section 90 during the molding of the plastic mold section 70.

[0094] As in Fig. As shown in Figure 2, the gate points 71a are positioned further inwards in the radial direction than the third annular projection 63. This ensures that the plastic flows smoothly from the gate on the inside to the outside in the radial direction during the forming of the plastic mold section 70, thus forming the plastic mold section 70 without difficulty. Furthermore, this allows the plastic to flow smoothly from a position near the third annular projection 63 during the forming of the plastic mold section 70, bringing relatively hot plastic into contact with the third annular projection 63. This allows a portion of the third annular projection 63 to be easily melted by the molten plastic. Consequently, the third annular projection 63 effectively seals the gap between the cover 61 and the plastic mold section 70.Furthermore, plastic that has passed radially outwards through the third annular projection 63 can flow into the radial space between the housing tube section 51 and the cover tube section 61b. This allows molten plastic poured from the sprue into the die to easily and relatively quickly come into contact with the first annular projection 54, located on the third step surface 51g on the inner circumferential surface of the housing tube section 51, and with the second annular projection 25, located on a portion of the upper surface of the stator plastic main section 24s, which is positioned further outwards radially than the cover tube section 61b.Accordingly, it can be achieved that relatively hot plastic is easily brought into contact with the first annular projection 54 and the second annular projection 25, and it can be achieved that the molten plastic easily melts part of the first annular projection 54 and part of the second annular projection 25. Accordingly, it can be achieved that the gap between the housing tube section 51 and the plastic mold section 70 can be easily sealed by the first annular projection 54, and it can be achieved that the gap between the stator plastic main section 24s and the plastic mold section 70 can be easily sealed by the second annular projection 25.

[0095] As in Fig. As shown in Figure 2, in the present embodiment a fourth annular projection 64, provided on the connector section 62, is embedded in the plastic mold section 70. In the present embodiment, the fourth annular projection 64 is embedded in the second annular plastic section 72. When the plastic mold section 70 is formed, part of the fourth annular projection 64 melts through the molten plastic poured into the die and mixes with the plastic forming the plastic mold section 70. Specifically, as mentioned above, the tip portion of the fourth annular projection 64 melts in the same way as the portion shown in Figure 2. Fig. The tip section 63c of the third annular projection 63, shown in Figure 7, acquires an irregular shape and mixes with the plastic that forms the plastic mold section 70. This gives the boundary between the fourth annular projection 64 and the plastic mold section 70 a plurality of shapes, thus preventing liquids, etc., from passing through this boundary. Therefore, even if, for example, a liquid enters at the boundary between the plastic mold section 70 and the connector section 62, the liquid can be contained at the boundary between the fourth annular projection 64 and the plastic mold section 70.Accordingly, by providing the fourth annular projection 64, which is embedded in the plastic mold section 70, on the connector section 62, the space between the plastic mold section 70 and the connector section 62 can be appropriately sealed. Specifically, with this embodiment, even if liquid from the outside of the electric pump 100 enters at the interface between the connector section 62 and the plastic mold section 70, the liquid can be contained at the interface between the fourth annular projection 64 and the plastic mold section 70.This prevents liquid from flowing into the boundary between the outer circumferential surface of the cover tube section 61b and the second annular plastic section 72, and prevents liquid from flowing from the boundary between the cover tube section 61b and the inner surface of the annular groove 24f into the interior of the circuit board receiving section 90.

[0096] As in Fig. As shown in Figure 1, the plastic mold section 70 has a projecting plastic section 74. The projecting plastic section 74 extends radially from the outer circumferential surface of the second annular projecting part 72 to the outer side, towards which the connector section 62 projects. As shown in Fig. As shown in Figure 2, a part of the section of the connector base 62a, which is positioned further outwards in the radial direction than the housing tube section 51, is embedded in the protruding plastic section 74.

[0097] Sections of the housing 50, the cover 61, and the stator plastic section 24 that are in contact with the plastic mold section 70 are, for example, welded to the plastic mold section 70. Sections of the housing 50, the cover 61, and the stator plastic section 24 that are in contact with the plastic mold section 70 are directly connected to the plastic mold section 70.

[0098] The plastic from which the housing 50, the stator plastic section 24, the cover 61, and the connector section 62 are formed is a plastic with a relatively low heat of fusion (melting energy) J / g. The heat of fusion of the plastic from which the housing 50, the stator plastic section 24, the cover 61, and the connector section 62 are formed is lower than the heat of fusion of polybutylene terephthalate (PBT). By forming the housing 50, the stator plastic section 24, the cover 61, and the connector section 62 from a plastic with a relatively low heat of fusion, it is possible to ensure that, during the molding of the plastic mold section 70, a portion of the annular projections provided on the individual components can be readily and appropriately melted by the molten plastic.As mentioned above, the individual annular projections can be used to seal the gaps between the plastic mold section 70 and the individual components in a suitable manner. Furthermore, by shaping the individual annular projections in a cross-section perpendicular to their direction of extension, forming an approximate triangle whose thickness decreases with increasing distance from the surface on which the individual annular projection is positioned, the tip of the individual annular projection can be melted more easily.

[0099] In the present embodiment, as mentioned above, the gap between the section on which each annular projection is provided and the plastic mold section 70 can be suitably sealed by providing the first annular projection 54, the second annular projection 25, the third annular projection 63, and the fourth annular projection 64. This makes it easy to ensure the tightness of the interior of the circuit board receiving section 90 and the interior of the pump receiving section 52, even if the plastic mold section 70 is reduced in size axially. Furthermore, it is easy to ensure the tightness of the housing tube section 51 and the cover tube section 61b by having the lower end of the cover tube section 61b fitted into the interior of the annular groove 24f, etc., to form the boundary of the respective related components extending from the outside to the inside of the circuit board mounting section 90, and the boundary of the respective related components extending from the inside of the pump mounting section 52 to the outside of the electric pump 100, into a complex labyrinth shape. This makes it easier to ensure the tightness of the inside of the circuit board mounting section 90 and the inside of the pump mounting section 52, even if the plastic mold section 70 is reduced in size in the axial direction.

[0100] The plastic from which the housing 50, the stator plastic section 24, the cover 61, and the connector section 62 are formed is, for example, syndiotactic polystyrene (SPS). The plastic from which the housing 50, the stator plastic section 24, the cover 61, and the connector section 62 are formed is the same. In the present embodiment, the plastic from which the plastic mold section 70 is formed is the same as the plastic from which the housing 50, the stator plastic section 24, the cover 61, and the connector section 62 are formed. However, the plastic from which the housing 50, the stator plastic section 24, the cover 61, the connector section 62, and the plastic mold section 70 are formed can also be different.

[0101] A worker, or the like, who manufactures the electric pump 100 of the aforementioned present embodiment, brings, as in Fig. Figure 8 shows, after fixing the switching plate 95 to the stator assembly 20, the cover assembly 60 from the top of the stator assembly 20. As shown in Fig. As shown in Figure 9, the worker, or similar person, fits the lower end of the cover tube section 61b into the interior of the annular groove 24f and positions the cover assembly 60 on the top of the stator assembly 20. At this point, the worker, or similar person, presses the second connection section 65b, which is an interference fit connection, into the hole section 95c of the switch plate 95 and electrically connects the plug terminal 65 to the switch plate 95.

[0102] As in Fig. As shown in 9, the worker and the like bring the rotor 10, which is integrally connected to the pump section 40, closer to the stator assembly 20 from above. The worker and the like, as shown in Fig. As shown in Figure 10, the fixing shaft 30 is inserted into the interior of the bearing 15 and the rotor 10 is positioned radially on the inside of the stator 20a. At this point, the rotor 10 is held radially on the inside of the stator 20a by the magnetic force of the magnet 12. The worker then brings a washer 32 closer from the underside of the fixing shaft 30 and inserts the fixing shaft 30 into the washer 32. A high-viscosity grease or similar substance is applied to the inside of the washer 32, and the viscosity of the grease prevents the washer 32 from falling off the fixing shaft 30.

[0103] As in Fig. As shown in Figure 10, the worker or equivalent inserts the assembly 100a, in which the switching plate 95, the cover assembly 60, the rotor 10, the pump section 40, and the washer 32 are mounted on the stator assembly 20, from the upper opening of the housing 50 into the interior of the housing 50. At this point, the worker or equivalent presses the stator plastic section 24 into the inner radial direction of the housing tube section 51. Furthermore, at this point, the worker or equivalent inserts the convex section 55, which is provided on the inner circumferential surface of the housing tube section 51, into the concave section 24e, which is provided on the outer circumferential surface of the stator plastic section 24.The worker or the like presses the assembly 100a, which includes the stator arrangement 20, into the inside in the radial direction of the housing tube section 51 until the fourth step surface 24g of the stator plastic section 24 is in contact with the first step surface 51e of the housing tube section 51.

[0104] As in Fig. As shown in Figure 11, the worker or the like places the assembly 100b, which was formed by arranging the assembly 100a inside the housing 50, inside the die M. The assembly 100b is an assembly that includes, among the components that make up the electric pump 100, components other than the plastic mold section 70. The die M has a cavity C for forming the plastic mold section 70. The die M has a plurality of sprues G on the upper end of the inside, radially in the direction of the section of the cavity C that forms the plastic cover section 71. The worker or the like pours molten plastic R from the sprues G into the interior of the cavity C.The plastic R, poured from the sprue G into the interior of cavity C, flows radially outwards in the section located on the top of the cover section 61a within cavity C and into the section located further outwards in cavity C than the cover tube section 61b. As the plastic R fills the interior of cavity C and hardens, the plastic mold section 70 is formed. This allows the housing 50, the cover 61, and the stator plastic section 24 to be joined via the plastic mold section 70, thus manufacturing the electric pump 100.

[0105] An embodiment that differs from the embodiment described above is described below. In the following explanation of the individual embodiments, with respect to a structure identical to the one described before the explanation of the individual embodiments, the explanation may be abbreviated by using appropriate, identical reference numerals. Furthermore, with respect to sections corresponding to individual parts of a structure described before the explanation of the individual embodiments, different reference numerals may be used alongside the same reference numerals to explain points that differ from the structure described above, and the explanation may be abbreviated with respect to points that correspond to the structure described above.With regard to a design where the following explanation of the individual embodiments has been abbreviated, a design may be adopted that corresponds to a design that was explained before the individual embodiments, provided that this does not differ in scope. Second embodiment

[0106] As in Fig. As shown in Figure 12, in a cover arrangement 260 of an electric pump 200 of the present embodiment, a plug section 262 projects from the section that is positioned further inwards in the radial direction than the plastic cover section 71 on the upper surface of the cover section 61a of the cover 61. The plug section 262 has a plug tube section 262b. The plug tube section 262b has a tubular shape that opens upwards. The central axis J leads into the inside of the plug tube section 262b. The lower end of the plug tube section 262b is connected to the upper surface of the cover section 61a. A portion of a plug connector 265 is embedded in the plug tube section 262b and is thereby held in place. In the present embodiment, the plug connector 265 extends in the axial direction.The connector 265 extends axially from the interior of the connector tube section 262b to the lower bottom section of the connector tube section 262b and is electrically connected to the switching plate 95. The remaining structure of the cover assembly 260 is identical to the remaining structure of the cover assembly 60 in the first embodiment.

[0107] A housing 250 is identical to the housing 50 in the first embodiment, except that it lacks a through-hole section 51 in a housing tube section 251. A plastic molded section 270 is identical to the plastic molded section 70 in the first embodiment, except that it lacks a section in contact with a connector section 262, such as the projecting plastic section 74. The remaining structure of the electric pump 200 is identical to the remaining structure of the electric pump 100 in the first embodiment. Third embodiment

[0108] As in Fig. As shown in Figure 13, a cover 361 of an electric pump 300 of the present embodiment, unlike the cover 61 of the first embodiment, does not have a cover pipe section 61b. The cover 361 has a first concave section 361c. In the present embodiment, the first concave section 361c is recessed downwards from the upper surface of a cover section 361a. The first concave section 361c has, for example, a ring shape that surrounds the central axis J. The first concave section 361c can also be provided in multiples at intervals in the circumferential direction. The inner surface of the first concave section 361c has an upward-facing surface, a radially inward-facing surface, and a radially outward-facing surface. The remaining structure of the cover 361 is the same as the remaining structure of the cover 61 in the first embodiment.

[0109] An upper end surface of a housing tube section 351 in a housing 350 is in contact with a lower surface on the outer edge in the radial direction of a cover section 361a. The housing 350 has a second concave section 351p. In the present embodiment, the second concave section 351p is recessed radially inwards from an outer circumferential surface of the housing tube section 351. The second concave section 351p has, for example, a ring shape that surrounds the central axis J. The second concave section 351p can also be provided in multiples at intervals in the circumferential direction. The second concave section 351p is spaced apart on the lower side from the upper end of the housing tube section 351. The inner surface of the second concave section 351p has a radially outward-facing surface, an upward-facing surface, and a downward-facing surface.The overall structure of the housing 350 is the same as the overall structure of the housing 50 in the first embodiment.

[0110] A plastic mold section 370 comprises a first plastic section 371 and a second plastic section 372. The first plastic section 371 is in contact with a radially outer section of the upper surface of a cover section 361a. The first plastic section 371 has an annular shape that surrounds the central axis J. The second plastic section 372 projects downwards from the outer edge of the first plastic section 371 in the radial direction. The second plastic section 372 has an annular shape that surrounds the central axis J. The second plastic section 372 is positioned on the outer surface in the radial direction of the cover section 361a and the housing tube section 351. The second plastic section 372 surrounds the cover section 361a and the housing tube section 351.The inner circumferential surface of the second plastic section 372 is in contact with the radially outer surface of the cover section 361a and the outer circumferential surface of the housing tube section 351. The lower end of the second plastic section 372 is positioned further down than the second concave section 351p.

[0111] The plastic mold section 370 has a first convex section 371b, which is positioned inside the first concave section 361c, and a second convex section 371c, which is positioned inside the second concave section 351p. This allows the plastic mold section 370 to be brought into contact with the inner surface of the first concave section 361c and the inner surface of the second concave section 351p. This increases the contact area between the plastic mold section 370 and the housing 350, as well as the contact area between the plastic mold section 370 and the cover 361. Consequently, the housing 350 and the cover 361 can be more firmly connected by the plastic mold section 370.

[0112] The first convex section 371b projects downwards from the lower surface of the first plastic section 371. The first convex section 371b fills the entire interior of the first concave section 361c. The first convex section 371b is in contact with the entire inner surface of the first concave section 361c. The second convex section 371c projects radially inwards from the inner circumferential surface of the second plastic section 372. The second convex section 371c fills the entire interior of the second concave section 351p. The second convex section 371b is in contact with the entire inner surface of the second concave section 351p.

[0113] The overall construction of the electric pump 300 is the same as the overall construction of the electric pump 100 in the first embodiment. Fourth embodiment

[0114] As in Fig.As shown in Figure 14, a cover 461 of an electric pump 400 of the present embodiment, unlike the cover 61 of the first embodiment, does not have a cover pipe section 61b. The cover 461 has a second through-hole 461d that penetrates a portion of the cover 461 in the axial direction. In the present embodiment, the second through-hole 461d penetrates a cover section 461a in the axial direction. The second through-hole 461d is, for example, provided in multiples at intervals around the circumference. The remaining structure of the cover 461 is the same as the remaining structure of the cover 61 in the first embodiment.

[0115] A housing 450 has a flanged section 458 that projects radially inward from the upper end of a housing tube section 451. The flanged section 458 has an annular shape that surrounds the central axis J. The upper surface of the flanged section 458 is in contact with the lower surface of a cover section 461a. The outer radial edge of the flanged section 458 is positioned radially in the same position as the outer radial edge of the cover section 461a.

[0116] The housing 450 has an axially extending expansion section 459. The expansion section 459 extends from below into the second through-hole 461d. In the present embodiment, the expansion section 459 projects upwards from the upper surface of the flange section 458. The upper end of the expansion section 459 is positioned higher than the upper surface of the cover section 461a. In other words, the expansion section 459 has a portion that is positioned higher than the second through-hole 461d. The expansion section 459 is spaced apart from the inner surface of the second through-hole 461d. The expansion section 459 can also be in contact with the inner surface of the second through-hole 461d. For example, the expansion section 459 is provided in multiples at intervals around the circumference.The majority of expansion sections 459 each lead in the axial direction into a majority of second through holes 461d.

[0117] The expansion section 459 has a third through-hole 459a that penetrates the expansion section 459 in a direction perpendicular to the axial direction. In the present embodiment, the third through-hole 459a penetrates the expansion section 459 in a radial direction. The third through-hole 459a is provided in a section that is positioned higher up in the expansion section 459 than the second through-hole 461d. In other words, the section that is positioned higher up in the expansion section 459 than the second through-hole 461d has a third through-hole 459a that the expansion section 459 penetrates in a direction perpendicular to the axial direction.

[0118] A plastic mold section 470 comprises a first plastic section 471, a second plastic section 472, and a third plastic section 475. The first plastic section 471 is in contact with a radially outer section of the upper surface of a cover section 461a. The first plastic section 471 has an annular shape that surrounds the central axis J. The inner radial edge of the first plastic section 471 is positioned further inward radially than the second through-hole 461d. The first plastic section 471 has a base 471d and a projection 471e. The base 471d is in contact with the upper surface of the cover section 461a. The projection 471e extends upward from the base 471d. Viewed axially, the projection 471e is aligned with the expansion section 459 and the second through-hole 461d.

[0119] The second plastic section 472 projects downwards from the outer edge of the first plastic section 471 in the radial direction. The second plastic section 472 has a ring shape that surrounds the central axis J. The second plastic section 472 is positioned on the outer surface in the radial direction of the cover section 461a and the flange section 458. The second plastic section 472 surrounds the cover section 461a and the flange section 458. The inner circumferential surface of the second plastic section 472 is in contact with the radially outer surface of the cover section 461a and the radially outer surface of the flange section 458.

[0120] The third plastic section 475 projects radially inwards from the lower end of the second plastic section 472. The third plastic section 475 has a ring shape that surrounds the central axis J. The third plastic section 475 is in contact with a radially outer section of the lower surface of the flange section 458. The third plastic section 475 does not need to be provided.

[0121] A section in which a third through-hole 459a is provided at the expansion section 459 is embedded in the plastic mold section 470. This places part of the plastic mold section 470 inside the third through-hole 459a, and the inner surface of the third through-hole 459a is in contact with the plastic mold section 470. This increases the contact area between the plastic mold section 470 and the housing 450, allowing for a more secure fixation between the two. Since the third through hole 459a is provided on a section that leads into the second through hole 461d on the expansion section 459 and projects upwards, the part of the expansion section 459 on which the third through hole 459a is provided is embedded in the plastic mold section 470 and thereby prevents the expansion section 459 from detaching downwards from the second through hole 461d.This allows the cover 461 and the housing 450 to be more securely connected via the plastic molded section 470.

[0122] In the present embodiment, a section positioned higher than the second through-hole 461d on the expansion section 459 is entirely embedded in the plastic mold section 470. This section extends to the base 471d and the projection 471e. The plastic mold section 470 includes a portion that fills the gap between the inner surface of the second through-hole 461d and the expansion section 459. This prevents the cover 461 from displacing radially relative to the housing 450.

[0123] The overall construction of the electric pump 400 is the same as the overall construction of the electric pump 100 in the first embodiment.

[0124] The present invention is not limited to the foregoing embodiments, and other structural elements and methods may be adopted that fall within the technically conceivable scope of the present invention. The plastic molded section can have any desired shape, provided that it is in contact with at least a part of the housing and at least a part of the cover and connects the housing and the cover. The plastic molded section need not be in contact with the stator plastic section, and the stator plastic section need not be connected to the housing and the cover. The housing need not be made of plastic. The housing can, for example, also be made of metal. The housing need not have a housing tube section. In this case, the plastic molded section can also connect the pump mounting section and the cover to the housing.The cover does not need to be made of plastic. It can also be made of metal, for example. The stator plastic section does not need to be provided.

[0125] The use of the pump suitable for the present invention is not particularly limited. The pump can be mounted on any machine. For example, the pump can be installed in a vehicle. The pump can also be a pump that transports any fluid. The pump can also be an oil pump that transports oil.

[0126] The present technology enables embodiments such as the following. (1) An electric pump comprising a rotatable rotor having a central axis as its center, a stator positioned radially on the outside of the rotor, a pump section connected axially to one side of the rotor, a switching plate positioned axially on the other side of the stator, a housing having a pump receiving section that receives the pump section internally, a cover that axially covers the switching plate from the other side, and a plastic molded section connecting the housing and the cover, being in contact with at least a portion of the housing and at least a portion of the cover. (2) The electric pump according to point (1), wherein the plastic molded section fills the gap between the housing and the cover on one complete revolution around the central axis.(3) The electric pump according to point (1) or (2), wherein the housing comprises a housing tube section that surrounds the stator radially from the outside and opens axially to the other side, wherein at least a portion of the portion that is positioned on the housing tube section further axially to the opposite side than the stator is in contact with the plastic molded section, and wherein the plastic molded section connects the housing tube section and the cover. (4) The electric pump according to point (3), wherein at least a portion of the portion that is positioned on the housing tube section further axially to the opposite side than the stator is embedded in the plastic molded section, wherein the housing tube section has a first through-hole in the portion that is embedded in the plastic molded section, which penetrates the housing tube section from the inner circumferential surface to the outer circumferential surface.(5) The electric pump according to point (3) or (4), wherein the cover comprises a cover section positioned axially on the opposite side of the switching plate and a cover tube section projecting axially from the cover section to one side, wherein at least a portion of the cover tube section is positioned radially on the inside of the housing tube section, and wherein the plastic molded section connects the housing tube section and the cover tube section. (6) The electric pump according to point (5), wherein the plastic molded section is in contact with the outer circumferential surface of the cover tube section, the inner circumferential surface of the housing tube section, the outer circumferential surface of the housing tube section, the surface on the opposite side of the cover section in the axial direction, and the end surface on the opposite side of the housing tube section in the axial direction.(7) The electric pump according to point (5) or (6), wherein the end on the other side of the casing tube section has the same axial position as the surface on the other side of the cover section, or is positioned further axially on one side than the surface on the other side of the cover section. (8) The electric pump according to any one of points (5) to (7), wherein an annular stepped surface is provided on the inner circumferential surface of the casing tube section, surrounding the central axis and directed axially to the other side, the casing having a first annular projection extending axially from the stepped surface to the other side, and being made of plastic, the first annular projection having a ring shape that surrounds the central axis and is embedded in the plastic mold section.(9) The electric pump according to any one of points (1) to (8) comprising a stator plastic section in which at least a part of the stator is embedded, wherein the plastic molded section is in contact with at least a part of the stator plastic section and connects the housing, the cover and the stator plastic section.(10) The electric pump according to any one of points (5) to (8), comprising a stator plastic section in which at least a part of the stator is embedded, wherein the plastic mold section is in contact with at least a part of the stator plastic section and connects the housing, the cover and the stator plastic section, wherein the stator plastic section has a stator plastic main section having a part which covers the stator from the other side in an axial direction, wherein the switching plate is positioned between the stator plastic main section and the cover section in an axial direction, and wherein the end on one side of the cover tube section is in axial contact with the stator plastic main section from the other side in an axial direction.(11) The electric pump according to point (10), wherein the stator plastic main section has an annular groove which is axially recessed on one side from the surface on the other side of the stator plastic main section and surrounds the central axis, wherein the end of one side of the cover tube section is axially fitted into the annular groove. (12) The electric pump according to point (10) or (11), wherein the stator plastic section has a first annular plastic section surrounding the central axis, wherein the first annular plastic section covers the outer surface of the stator radially around its entire circumference, and wherein the first annular plastic section is radially fitted into the inner surface of the casing tube section.(13) The electric pump according to point (12), wherein the inner circumferential surface of the housing tube section has an inner circumferential surface section which is provided radially spaced from the outer circumferential surface of the first annular plastic section to the outside, wherein the inner circumferential surface section is positioned further on the other side in the axial direction than the section of the inner circumferential surface of the housing tube section into which the first annular plastic section is fitted, wherein the plastic mold section has a part which fills the space in the radial direction between the inner circumferential surface section and the outer circumferential surface of the first annular plastic section.(14) The electric pump according to one of points (10) to (13), wherein the plastic molded section is in contact with the outer circumferential surface of the cover tube section, the inner circumferential surface of the housing tube section, the outer circumferential surface of the housing tube section, the surface on the other side of the cover section in the axial direction, the end surface on the other side of the housing tube section in the axial direction, the surface on the other side of the stator plastic main section in the axial direction and the surface on the outside of the stator plastic main section in the radial direction.(15) The electric pump according to any one of points (10) to (14), wherein the stator plastic section has a second annular projection extending axially from a section positioned on the surface on the other side of the stator plastic main section further outwards in the radial direction than the cover tube section, the second annular projection having a ring shape surrounding the central axis and further embedded in the plastic mold section.(16) The electric pump according to any one of points (10) to (15), wherein the plastic mold section has a portion which is in axial contact with a surface on the opposite side of the cover section, the cover having a third circular projection which extends axially from the surface on the opposite side of the cover section in the opposite direction, and which is made of plastic, wherein the third annular projection has a ring shape surrounding the central axis and is embedded in the plastic mold section. (17) The electric pump according to point (16), wherein the third annular projection is provided in a plurality at intervals in the radial direction.(18) The electric pump according to point (16) or (17), wherein the plastic mold section has a second annular plastic section in a ring shape surrounding the central axis, the second annular plastic section being positioned radially on the outside of the cover tube section, with a sprue point being provided on the surface on the other side of the plastic mold section in the axial direction, the sprue point being located further radially on the inside than the third annular projection.(19) The electric pump according to any one of points (1) to (18), wherein the cover has a second through-hole which penetrates a part of the cover in the axial direction, wherein the housing has an expansion section which extends in the axial direction and from one side in the axial direction to the second through-hole, wherein the expansion section has a part which is positioned further on the other side in the axial direction than the second through-hole, wherein a part of the expansion section which is positioned further on the other side in the axial direction than the second through-hole has a third through-hole which penetrates the expansion section in a direction perpendicular to the axial direction, wherein the part of the expansion section in which the third through-hole is provided is embedded in the plastic mold section.(20) The electric pump according to any one of points (1) to (19), wherein the cover has a first concave section, wherein the housing has a second concave section, wherein the plastic mold section has a part that is positioned inside the first concave section and a part that is positioned inside the second concave section.

[0127] The structural elements and methods described above in this disclosure can be combined in any way, provided they do not contradict each other. Explanation of reference symbols

[0128] 10...Rotor, 20a... Stator, 24...Stator plastic section, 24b...First annular plastic section, 24e...Concave section, 24f...Annular groove, 24s...Stator plastic main section, 25...Second annular projection, 40...Pump section, 50, 250, 350, 450...Housing, 51, 251, 351, 451...Housing tube section, 51g...Third step surface (step surface), 51h...First through hole, 51k...Inner circumferential surface section, 52...Pump receiving section, 54...First annular projection, 61, 361, 461...Cover, 61a, 361a, 461a...Cover section, 61b...Cover tube section, 63, 63a, 63b...Third annular Projection, 70, 270, 370, 470... Plastic mold section, 71a... Gate, 72... Second annular plastic section, 95... Switch plate, 100, 200, 300, 400... Electric pump, 351p... Second concave section, 361c... First concave section, 459... Expansion section, 459a... Third through hole, 461d... Second through hole, G... Gate, J... Center axis

Claims

[1] Electric pump comprising: a rotatable rotor with a central axis as its center point, a stator that is positioned radially on the outside of the rotor, a pump section that is connected to one side of the rotor in the axial direction, a switching plate positioned on the other side in the axial direction of the stator, a housing that has a pump receiving section which accommodates the pump section inside, a cover that covers the switching plate from the other side in the axial direction, and a plastic molded section that connects the housing and the cover, being in contact with at least a part of the housing and at least a part of the cover. [2] Electric pump according to claim 1, wherein the plastic molded section fills the gap between the housing and the cover on a complete circumnavigation around the central axis. [3] Electric pump according to claim 1 or 2, wherein the housing has a housing tube section that surrounds the stator from the outside in a radial direction and opens to the other side in an axial direction, wherein at least a part of the section which is positioned further on the other side of the stator in the axial direction on the housing tube section is in contact with the plastic molded section and the plastic molded section connects the housing tube section and the cover. [4] Electric pump according to claim 3, wherein at least a part of the part which is positioned further on the other side of the stator in the axial direction on the housing tube section is embedded in the plastic molded section, wherein the housing tube section in the section which is embedded in the plastic mold section has a first through hole which penetrates the housing tube section from the inner circumferential surface to the outer circumferential surface. [5] Electric pump according to claim 3 or 4, wherein the cover has a lid section that is positioned on the other side of the switching plate in the axial direction, and a cover pipe section that projects axially from the cover section to one side, wherein at least a part of the cover tube section is positioned radially on the inside of the housing tube section and wherein the plastic molded section connects the housing tube section and the cover tube section. [6] Electric pump according to claim 5, wherein the plastic molded section is in contact with the outer circumferential surface of the cover tube section, the inner circumferential surface of the housing tube section, the outer circumferential surface of the housing tube section, the surface on the other side of the cover section in the axial direction and the end surface on the other side of the housing tube section in the axial direction. [7] Electric pump according to claim 5 or 6, wherein the end on the other side of the housing tube section has the same axial position as the surface on the other side of the cover section or is positioned further on one side in the axial direction than the surface on the other side of the cover section. [8] Electric pump according to one of claims 5 to 7, wherein an annular stepped surface is provided on the inner circumferential surface of the housing tube section, which surrounds the central axis and is directed axially to the other side, wherein the housing has a first annular projection which projects axially from the stepped surface to the other side, and is made of plastic, wherein the first ring-shaped projection has a ring shape that surrounds the central axis and is embedded in the plastic mold section. [9] Electric pump according to any one of claims 1 to 8, comprising a stator plastic section in which at least a part of the stator is embedded, wherein the plastic molded section is in contact with at least a part of the stator plastic section and connects the housing, the cover and the stator plastic section. [10] Electric pump according to any one of claims 5 to 8, comprising a stator plastic section in which at least a part of the stator is embedded, wherein the plastic molded section is in contact with at least a part of the stator plastic section and connects the housing, the cover and the stator plastic section, wherein the stator plastic section comprises a stator plastic main section which has a part that covers the stator from the other side in the axial direction, wherein the switching plate is positioned in the axial direction between the stator plastic main section and the cover section, and wherein the end on one side of the cover tube section is in axial contact with the stator plastic main section from the other side in axial direction. [11] Electric pump according to claim 10, wherein the stator plastic main section has an annular groove which is recessed axially on one side from the surface on the other side of the stator plastic main section and surrounds the central axis, wherein the end of one side of the cover pipe section is fitted into the annular groove in the axial direction. [12] Electric pump according to claim 10 or 11, wherein the stator plastic section has a first annular plastic section surrounding the central axis, wherein the first ring-shaped plastic section covers the outer surface of the stator in the radial direction around the entire circumference of the central axis, wherein the first ring-shaped plastic section is fitted into the inside of the housing tube section in a radial direction. [13] Electric pump according to claim 12, wherein the inner circumferential surface of the housing tube section has an inner circumferential surface section which is provided spaced radially apart from the outer circumferential surface of the first annular plastic section to the outside, wherein the inner circumferential surface section is positioned further on the opposite side in the axial direction than the part of the inner circumferential surface of the housing tube section into which the first annular plastic section is fitted, wherein the plastic mold section has a part that fills the space in the radial direction between the inner circumferential surface section and the outer circumferential surface of the first annular plastic section. [14] Electric pump according to one of claims 10 to 13, wherein the plastic molded section is in contact with the outer circumferential surface of the cover tube section, the inner circumferential surface of the housing tube section, the outer circumferential surface of the housing tube section, the surface on the other side in the axial direction of the cover section, the end surface on the other side in the axial direction of the housing tube section, the surface on the other side in the axial direction of the stator plastic main section and the surface on the outside in the radial direction of the stator plastic main section. [15] Electric pump according to one of claims 10 to 14, wherein the stator plastic section has a second annular projection which extends from a part which is positioned further outwards in the radial direction than the cover tube section on the surface on the other side in the axial direction of the stator plastic main section to the other side in the axial direction, wherein the second annular projection has a ring shape which surrounds the central axis and is embedded in the plastic mold section. [16] Electric pump according to any one of claims 10 to 15, wherein the plastic mold section has a part which is in contact with a surface on the other side in the axial direction of the lid section, wherein the cover has a third annular projection which extends from the surface on the opposite side in the axial direction of the cover section in the other axial direction, and is made of plastic, wherein the third annular projection has a ring shape that surrounds the central axis and is embedded in the plastic mold section. [17] Electric pump according to claim 16, wherein the third annular projection is provided in a plurality in the radial direction at intervals. [18] Electric pump according to claim 16 or 17, wherein the plastic mold section has a second annular plastic section in a ring shape surrounding the central axis, wherein the second annular plastic section is positioned radially on the outside of the cover tube section, wherein a sprue point is provided on the surface on the other side of the plastic mold section in the axial direction, the sprue point is located further on the inside in the radial direction than the third ring-shaped projection. [19] Electric pump according to any one of claims 1 to 18, wherein the cover has a second through-hole which penetrates part of the cover in the axial direction, wherein the housing has an expansion section that extends in the axial direction and runs from one side in the axial direction to the second through-hole, wherein the expansion section has a part that is positioned further on the other side in the axial direction than the second through hole, wherein a part of the expansion section, which is positioned further on the other side in the axial direction than the second through-hole, has a third through-hole that penetrates the expansion section in a direction perpendicular to the axial direction, wherein the part of the expansion section where the third through-hole is provided is embedded in the plastic mold section. [20] Electric pump according to any one of claims 1 to 19, wherein the cover has a first concave section, the case has a second concave section, wherein the plastic mold section has a part that is positioned inside the first concave section and a part that is positioned inside the second concave section.

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