Pump

Abstract

To provide a pump having a structure capable of reducing manufacturing man-hours and time while securing a sealing performance between a rotor and a stator.SOLUTION: A pump according to an embodiment of the present invention comprises: a rotor capable of rotating around a center axis; a stator located on an outside in a radial direction of the rotor, and surrounding the rotor; a pump part connecting to one side in an axial direction of the rotor; a supporting member comprising a base part covering the stator from the one side in the axial direction, and a non-magnetic rotor housing part located on the inside in the radial direction of the stator, and internally housing the rotor; and a fixing member located on the outside in the radial direction of the stator, and surrounding the stator. The rotor housing part comprises a lid part covering the rotor from the other side in the axial direction, and a cylindrical part located between the rotor and the stator in the radial direction, and opened on the one side in the axial direction. The stator is fixed to the fixing member. The fixing member is fixed to the supporting member.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pump.

Background Art

[0002] An electric pump having a rotor and a stator is known. For example, Patent Document 1 describes a water pump.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a pump such as the water pump as described above, in order to prevent the fluid sent by the pump from contacting the stator, the entire stator may be covered with a resin mold and sealed with a gap between the rotor and the stator. In this case, there is a problem that the man-hours and time for the work of molding the resin mold increase, and the man-hours and time for manufacturing the pump are likely to increase.

[0005] In view of the above circumstances, an object of the present invention is to provide a pump having a structure capable of reducing the man-hours and time for manufacturing while ensuring the sealing performance between the rotor and the stator.

Means for Solving the Problems

[0006] One embodiment of the pump of the present invention comprises a rotor rotatable about a central axis, a stator located radially outside the rotor and surrounding the rotor, a pump section connected to one axial side of the rotor, a support member having a base that covers the stator from one axial side and a rotor housing section made of a non-magnetic material located radially inside the stator and housing the rotor inside, and a fixing member located radially outside the stator and surrounding the stator. The rotor housing section has a lid that covers the rotor from the other axial side and a cylindrical section located radially between the rotor and the stator and opening to one axial side. The stator is fixed to the fixing member. The fixing member is fixed to the support member. [Effects of the Invention]

[0007] According to one aspect of the present invention, it is possible to reduce the man-hours and time required to manufacture a pump while ensuring a seal between the rotor and the stator. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a cross-sectional view showing a pump according to one embodiment. [Figure 2] Figure 2 is a perspective view showing a support member of one embodiment. [Figure 3] Figure 3 is a perspective view showing a part of a pump according to one embodiment. [Modes for carrying out the invention]

[0009] Each figure virtually shows the central axis J of the pump 100 in the embodiment described below. In the following description, the axial direction of the central axis J is simply referred to as the "axial direction." The radial direction centered on the central axis J is simply referred to as the "radial direction." The circumferential direction centered on the central axis J is simply referred to as the "circumferential direction." The Z-axis shown in each figure indicates the direction in which the central axis J extends. In the following description, the side of the axial direction in which the Z-axis arrow points (+Z side) is referred to as the "upper side," and the side of the axial direction opposite to the side in which the Z-axis arrow points (-Z side) is referred to as the "lower side."

[0010] In this embodiment, the lower side corresponds to "one side in the axial direction," and the upper side corresponds to "the other side in the axial direction." Note that "upper side" and "lower side" are merely names used to describe the relative positional relationship of each part, and the actual arrangement may be different from the arrangement indicated by these names. Also, in Figure 1, for illustrative purposes, cross-sections at different circumferential positions are shown on both the left and right sides of the central axis J.

[0011] The pump 100 of this embodiment shown in Figure 1 is a water pump for supplying water. As shown in Figure 1, the pump 100 of this embodiment comprises a support member 10, a cover member 20, a fixing member 30, a fixing shaft 40, a rotor 50, a pump section 60, a stator 70, and a base plate 80. The support member 10 and the cover member 20 are fixed to each other in the axial direction and constitute a case 110 that houses the stator 70 and the base plate 80 inside.

[0012] The support member 10 is located below the cover member 20. The support member 10 is made of a non-magnetic material. In this embodiment, the support member 10 is made of resin. As shown in Figure 2, the support member 10 has a bottom wall portion 11, a rotor housing portion 12, a first annular wall portion 13, a second annular wall portion 14, a third annular wall portion 15, a flange portion 16, substrate fixing portions 17a, 17b, a pin portion 18, and a connector portion 19. The bottom wall portion 11, the first annular wall portion 13, the second annular wall portion 14, the third annular wall portion 15, and the flange portion 16 constitute a base portion 10a that covers the stator 70 from below.

[0013] The bottom wall portion 11 is an annular shape surrounding the central axis J. As shown in Figure 1, the bottom wall portion 11 is located below the stator 70. A recess 11a is provided in the radially inward portion of the lower surface of the bottom wall portion 11, which is recessed upward. The recess 11a is an annular shape surrounding the central axis J. The recess 11a opens radially inward.

[0014] The rotor housing 12 extends upward from the bottom wall 11. More specifically, the rotor housing 12 extends upward from the radially inner peripheral edge of the bottom wall 11. The rotor housing 12 is cylindrical, surrounding the central axis J and opening downward. The rotor housing 12 houses the rotor 50 inside. The rotor housing 12 is made of a non-magnetic material. In this embodiment, the rotor housing 12 is made of resin. The rotor housing 12 has a lid 12a that covers the rotor 50 from above, and a cylindrical portion 12b that extends downward from the lid 12a.

[0015] The lid portion 12a is disc-shaped with respect to the central axis J. The lid portion 12a has a retaining portion 12c on its lower surface. The retaining portion 12c is the part that holds the upper end of the fixed shaft 40. The retaining portion 12c protrudes downward from the rest of the lid portion 12a. The retaining portion 12c has a projection 12d that covers at least a portion of the inner surface of the hole portion 43 of the fixed shaft 40, which will be described later. The projection 12d is located inside the hole portion 43. The projection 12d is in contact with the inner surface of the hole portion 43. In this embodiment, the projection 12d is in contact with the entire inner surface of the hole portion 43. The projection 12d is filled inside the hole portion 43. More specifically, the projection 12d fills the entire inside of the hole portion 43, except for the fastening hole 12e, which will be described later. In this embodiment, the projection 12d is cylindrical with respect to the central axis J. The projection 12d protrudes below the portion of the holding portion 12c that is located radially outward from the projection 12d. The lower end of the projection 12d is located above the lower end of the cylindrical portion 12b.

[0016] As shown in Figure 2, the lid portion 12a has a plurality of recesses 12f that are recessed downward from the radially outer portion of the upper surface of the lid portion 12a. The plurality of recesses 12f are arranged at equal intervals along the circumference. A pin portion 18 is provided on the radial outer edge of the lid portion 12a. The pin portion 18 is cylindrical and protrudes upward from the lid portion 12a.

[0017] The cylindrical portion 12b extends downward from the radial outer peripheral edge of the lid portion 12a and connects to the radial inner peripheral edge of the bottom wall portion 11. As shown in Figure 1, the cylindrical portion 12b is located radially between the rotor 50 and the stator 70. The cylindrical portion 12b is open on the downward side. The radial thickness of the wall portion constituting the cylindrical portion 12b is smaller than the axial thickness of the lid portion 12a. However, the radial thickness of the wall portion constituting the cylindrical portion 12b may be larger than the axial thickness of the lid portion 12a, or it may be the same as the axial thickness of the lid portion 12a.

[0018] The rotor housing 12 is provided with fastening holes 12e. The fastening holes 12e are circular holes that are recessed downwards from the upper surface of the lid 12a, with the central axis J as the center. The fastening holes 12e extend to the projection 12d. The fastening holes 12e are holes with a bottom on the lower side. The lower end of the fastening holes 12e is located below the portion of the holding portion 12c other than the projection 12d. The lower end of the fastening holes 12e is located below the upper end of the rotor 50. Note that the lower end of the fastening holes 12e may be located above the upper end of the rotor 50, or it may be located in the same axial position as the upper end of the rotor 50.

[0019] As shown in Figure 2, the first annular wall portion 13, the second annular wall portion 14, and the third annular wall portion 15 protrude upward from the bottom wall portion 11. The first annular wall portion 13, the second annular wall portion 14, and the third annular wall portion 15 are annular in shape, surrounding the central axis J. The first annular wall portion 13 is located radially outward from the rotor housing portion 12 and surrounds the rotor housing portion 12. The upper end of the first annular wall portion 13 is located lower than the upper end of the rotor housing portion 12. The second annular wall portion 14 is located radially outward from the first annular wall portion 13 and surrounds the first annular wall portion 13. The upper end of the second annular wall portion 14 is located higher than the upper end of the first annular wall portion 13 and lower than the upper end of the rotor housing portion 12. The third annular wall portion 15 is located radially outward from the second annular wall portion 14 and surrounds the second annular wall portion 14. The upper end of the third annular wall portion 15 is located above the upper end of the second annular wall portion 14 and below the upper end of the rotor housing portion 12.

[0020] The second annular wall portion 14 is provided with a fixed portion 14a. The fixed portion 14a is columnar and extends in the axial direction. The fixed portion 14a protrudes radially outward on both sides from the portions on both circumferential sides of the fixed portion 14a in the second annular wall portion 14. The fixed portion 14a has a fastening hole 14c that is recessed downward from the upper surface of the fixed portion 14a. A plurality of fixed portions 14a are provided at intervals in the circumferential direction. The plurality of fixed portions 14a are arranged at equal intervals along the circumferential direction over one full turn. For example, four fixed portions 14a are provided. Note that the number and arrangement of the fixed portions 14a are not particularly limited.

[0021] On the upper surface of the second annular wall portion 14, fitting protrusions 14b that protrude upward are provided. That is, in the present embodiment, the support member 10 has fitting protrusions 14b that protrude in the axial direction. In the present embodiment, the fitting protrusions 14b are columnar. A plurality of fitting protrusions 14b are provided at intervals in the circumferential direction. In the present embodiment, two fitting protrusions 14b are provided between adjacent fixed portions 14a in the circumferential direction. That is, a total of eight fitting protrusions 14b are provided. Ribs 14d that protrude radially outward on both sides from the second annular wall portion 14 are provided at the portions of the second annular wall portion 14 where the fixed portions 14a are provided and the portions where the fitting protrusions 14b are provided. The ribs 14d connect the first annular wall portion 13 and the third annular wall portion 15.

[0022] The flange portion 16 extends radially outward from the third annular wall portion 15. The flange portion 16 is annular and surrounds the central axis J. A cover member 20 is fixed to the flange portion 16 from above. The flange portion 16 is a portion that is fixed to the equipment to which the pump 100 is attached. A connector portion 19 is provided on the flange portion 16.

[0023] The substrate fixing portions 17a and 17b are the portions where the substrate 80 is fixed. The substrate fixing portion 17a is cylindrical and protrudes upward from the bottom wall portion 11. The substrate fixing portion 17a is located between the second annular wall portion 14 and the third annular wall portion 15 in the radial direction. The upper end of the substrate fixing portion 17a protrudes above the third annular wall portion 15 and the rotor accommodating portion 12. A plurality of substrate fixing portions 17a are provided at intervals in the circumferential direction. For example, four substrate fixing portions 17a are provided. The substrate fixing portion 17b is cylindrical and protrudes upward from the radially outer peripheral edge portion of the lid portion 12a. The upper end of the substrate fixing portion 17b is located at the same position as the upper end of the substrate fixing portion 17a in the axial direction. A pair of substrate fixing portions 17b are provided with the central axis J interposed therebetween in the radial direction. Fastening holes for screwing in screws for fixing the substrate 80 are provided on the upper end surfaces of the substrate fixing portions 17a and 17b. The screws for fixing the substrate 80 are, for example, tapping screws.

[0024] As shown in FIG. 1, the cover member 20 is fixed above the support member 10. In the present embodiment, the cover member 20 is made of metal. The cover member 20 has a container shape with an opening on the lower side. The cover member 20 includes a top wall portion 21 that covers the substrate 80 from above, an outer peripheral wall portion 22 that extends downward from the radially outer peripheral edge portion of the top wall portion 21, and a flange portion 23 that protrudes radially outward from the lower end portion of the outer peripheral wall portion 22. The flange portion 23 is fixed above the flange portion 16 of the support member 10. The space between the flange portion 23 and the flange portion 16 in the axial direction is sealed by an O-ring 93.

[0025] The fixing member 30 is fixed above the support member 10. The fixing member 30 is located inside the cover member 20 in the radial direction. The fixing member 30 is located outside the stator 70 in the radial direction. The fixing member 30 surrounds the stator 70. In the present embodiment, the fixing member 30 is made of metal. The material constituting the fixing member 30 is, for example, iron. The fixing member 30 is made, for example, by subjecting a sheet metal member to press working. In the present embodiment, the fixing member 30 is a cylindrical member with an opening on the lower side. The fixing member 30 includes a top wall portion 31, a peripheral wall portion �2, and a fixing flange portion 33.

[0026] The top wall portion 31 is disc-shaped with a central axis J at its center. The top wall portion 31 is located above the lid portion 12a. The top wall portion 31 is fixed to the upper side of the lid portion 12a with a screw 92. The lower surface of the top wall portion 31 is in contact with the upper surface of the lid portion 12a. However, the lower surface of the top wall portion 31 may not be in contact with the upper surface of the lid portion 12a, but may be positioned opposite the upper surface of the lid portion 12a with a gap in between. The top wall portion 31 has a first through hole 31a through which the screw 92 is passed from above. The first through hole 31a is a circular hole that penetrates the top wall portion 31 axially. The screw 92 is passed through the first through hole 31a from above and tightened into the fastening hole 12e. In this embodiment, the screw 92 is a tapping screw. Before the screw 92 is tightened, there is no threaded portion on the inner circumferential surface of the fastening hole 12e. The inner circumferential surface of the fastening hole 12e is threaded when the screw 92 is tightened into the fastening hole 12e. At least a portion of the screw 92 is tightened into the projection 12d. In this embodiment, the lower portion of the screw 92 is tightened into the fastening hole 12e provided in the projection 12d. The lower end of the screw 92 is located in approximately the same position in the axial direction as the upper end of the rotor 50. The top wall portion 31 protrudes radially outward from the cover portion 12a. The radially outward portion of the top wall portion 31 is located above the stator 70.

[0027] As shown in Figure 3, the top wall portion 31 has a second through-hole 31b that penetrates the top wall portion 31 in the axial direction. The second through-hole 31b is a circular hole. The inner diameter of the second through-hole 31b is larger than the inner diameter of the first through-hole 31a. A pair of second through-holes 31b are provided, sandwiching the first through-hole 31a radially. Each of the pair of second through-holes 31b is passed through each of the substrate fixing portions 17b from below in the axial direction.

[0028] The top wall portion 31 has a third through-hole 31c that penetrates the top wall portion 31 in the axial direction. The third through-hole 31c is a circular hole. The inner diameter of the third through-hole 31c is smaller than the inner diameter of the first through-hole 31a and the inner diameter of the second through-hole 31b. The third through-hole 31c is located adjacent to one of the second through-holes 31b on one side in the circumferential direction. A pin portion 18 is passed through the third through-hole 31c from below in the axial direction. The pair of second through-holes 31b and the third through-hole 31c are arranged asymmetrically with respect to the central axis J. Therefore, by passing the pair of substrate fixing portions 17b through the pair of second through-holes 31b and the pin portion 18 through the third through-hole 31c, it is easy to prevent the fixing member 30 from being assembled in the wrong orientation. The pin portion 18 is inserted into a hole (not shown) provided in the substrate 80. The pin portion 18 allows the fixing member 30 and the substrate 80 to be positioned.

[0029] The peripheral wall portion 32 extends downward from the radial outer edge of the top wall portion 31. The peripheral wall portion 32 is cylindrical, surrounding the central axis J and opening downward. As shown in Figure 1, the peripheral wall portion 32 is located radially outside the stator 70. The peripheral wall portion 32 is fixed to the outer surface of the stator 70. In this embodiment, the stator 70 is fixed inside the peripheral wall portion 32 by press-fitting.

[0030] The fixed flange portion 33 extends radially outward from the peripheral wall portion 32. More specifically, the fixed flange portion 33 extends radially outward from the lower end of the peripheral wall portion 32. The fixed flange portion 33 is an annular shape surrounding the central axis J, and is plate-shaped with its surface facing axially. The fixed flange portion 33 is located above the second annular wall portion 14. The fixed flange portion 33 is supported from below by the second annular wall portion 14 and the ribs 14d provided on the second annular wall portion 14.

[0031] The fixing flange portion 33 is fixed to the fixed portion 14a provided on the second annular wall portion 14 by screws 91. As a result, the fixing flange portion 33 is fixed to the base portion 10a of the support member 10 from above. The fixing member 30 is also fixed to the support member 10. In this embodiment, the fixing flange portion 33 is fixed to each of the four fixed portions 14a by screws 91.

[0032] The fixed flange portion 33 has a through hole 33a through which a screw 91 is passed axially. The through hole 33a is a circular hole that penetrates the fixed flange portion 33 axially. As shown in Figure 3, in this embodiment, four through holes 33a are provided at equal intervals along the circumference. The number and arrangement of the through holes 33a are not particularly limited. The screw 91 is passed axially through the through hole 33a from above and tightened into the fastening hole 14c of the fixed portion 14a. The screw 91 is, for example, a tapping screw. Before the screw 91 is tightened, there is no thread on the inner circumferential surface of the fastening hole 14c. Threads are cut into the inner circumferential surface of the fastening hole 14c when the screw 91 is tightened into the fastening hole 14c.

[0033] The fixed flange portion 33 has a fitting hole portion 33b into which the fitting projection 14b is fitted. In this embodiment, the fitting hole portion 33b is a circular hole that penetrates the fixed flange portion 33 in the axial direction. Multiple fitting holes 33b are provided at intervals in the circumferential direction. Eight fitting holes 33b are provided. Each fitting projection 14b is fitted into each fitting hole portion 33b by passing it through in the axial direction from below. The clearance between the fitting hole portion 33b and the fitting projection 14b is smaller than the clearance between the second through hole 31b and the substrate fixing portion 17b and the clearance between the third through hole 31c and the pin portion 18. The number of fitting holes 33b and fitting projections 14b that fit together is not particularly limited. The shape of the fitting hole portion 33b and the shape of the fitting projection 14b are not particularly limited.

[0034] The fixing member 30 has through-holes 34. The through-holes 34 are provided spanning the top wall portion 31 and the peripheral wall portion 32. The through-holes 34 penetrate the radial outer edge of the top wall portion 31 in the axial direction and penetrate the upper end of the peripheral wall portion 32 in the radial direction. Multiple through-holes 34 are provided at equal intervals along the circumference. For example, six through-holes 34 are provided.

[0035] As shown in Figure 1, the fixed shaft 40 extends in the axial direction. The fixed shaft 40 is cylindrical with a central axis J. The upper end of the fixed shaft 40 is held by the retaining portion 12c. In this way, the fixed shaft 40 is fixed to the rotor housing portion 12. In this embodiment, the upper end of the fixed shaft 40 is embedded in and held by the retaining portion 12c. The retaining portion 12c is made by insert molding using the fixed shaft 40 as the insert member. The fixed shaft 40 extends downward from the retaining portion 12c. The lower end of the fixed shaft 40 is located below the rotor housing portion 12.

[0036] The upper end of the fixed shaft 40 is provided with a recessed hole 43 on the lower side. The hole 43 has a bottom on the lower side and is a circular hole centered on the central axis J. The lower end of the hole 43 is located below the upper end of the rotor 50. A projection 12d is located inside the hole 43. A slip washer 44 and an O-ring 45 are attached to the outer circumferential surface of the portion of the fixed shaft 40 located below the rotor housing portion 12. The slip washer 44 is positioned opposite the lower side of the extension portion 53b of the rotor 50, which will be described later. The O-ring 45 is attached to the portion of the fixed shaft 40 located below the portion to which the slip washer 44 is attached.

[0037] The fixed shaft 40 has a cylindrical fixed shaft body portion 41 extending in the axial direction, and a fixed shaft flange portion 42 projecting radially outward from the upper end of the fixed shaft body portion 41. The fixed shaft flange portion 42 is annular in shape, surrounding the central axis J. The upper end of the fixed shaft body portion 41 and the fixed shaft flange portion 42 are embedded in and held by the holding portion 12c. The fixed shaft flange portion 42 is embedded in the holding portion 12c, causing it to catch on the holding portion 12c in the axial direction. This prevents the fixed shaft 40 from coming out of the holding portion 12c downward.

[0038] The rotor 50 is rotatable about a central axis J. The rotor 50 is housed inside the rotor housing 12. The rotor 50 includes a rotor core 51, magnets 52, and a resin part 53. The rotor core 51 is annular in shape surrounding the central axis J. A fixed shaft 40 is passed axially through the radially inner side of the rotor core 51. The magnets 52 are fixed to the rotor core 51. In this embodiment, the magnets 52 are arranged in a hole that penetrates the rotor core 51 axially. Multiple magnets 52 are provided, for example, spaced apart in the circumferential direction.

[0039] The resin portion 53 is cylindrical, enclosing the central axis J and extending in the axial direction. The fixed shaft 40 is passed axially through the radially inner side of the resin portion 53. The fixed shaft 40 is fitted into the radially inner side of the resin portion 53. The fixed shaft 40 supports the rotor 50 so that it can rotate by supporting the inner circumferential surface of the resin portion 53. The resin portion 53 has a covering portion 53a into which the rotor core 51 and magnet 52 are embedded and held, and an extension portion 53b extending downward from the covering portion 53a. The covering portion 53a covers the entire rotor core 51 and the entire magnet 52. The covering portion 53a has a portion located radially between the fixed shaft 40 and the rotor core 51. The outer diameter of the extension portion 53b is smaller than the outer diameter of the covering portion 53a. The lower end of the extension portion 53b protrudes below the rotor housing portion 12. The inner diameter of the coated portion 53a and the inner diameter of the stretched portion 53b are the same.

[0040] The outer circumferential surface of the resin portion 53 is the outer circumferential surface of the rotor 50. The outer circumferential surface of the resin portion 53 is located radially inward from the inner circumferential surface of the rotor housing portion 12. The outer circumferential surface of the covering portion 53a faces the inner circumferential surface of the rotor housing portion 12 with a small gap between them.

[0041] The pump section 60 is connected to the underside of the rotor 50. In this embodiment, the pump section 60 is an impeller. The pump section 60 is made of resin. The pump section 60 has an impeller body 61 and a shroud 62. In this embodiment, the impeller body 61 is connected to the lower end of the extension 53b. The resin section 53 and the impeller body 61 are part of the same single component. The resin portion, including the resin section 53 and the impeller body 61, is made, for example, by insert molding using the rotor core 51 and magnet 52 as insert members. The impeller body 61 has a base section 61a that extends radially outward from the outer circumferential surface of the extension 53b, and a plurality of blade sections 63 provided on the lower surface of the base section 61a. The upper end of the base section 61a is located in a recess 11a provided in the bottom wall 11.

[0042] The shroud portion 62 is a separate component from the impeller body portion 61. The shroud portion 62 is fixed to the lower side of the impeller body portion 61. The shroud portion 62 has an annular ring portion 62a surrounding the central axis J, and a cylindrical portion 62b extending downward from the radially inner peripheral edge of the ring portion 62a. The ring portion 62a is positioned separately below the radially outer portion of the base portion 61a.

[0043] The pump unit 60 has an inlet 64 and a discharge port 65. The inlet 64 is the lower end of the cylindrical portion 62b and opens downwards. The discharge port 65 is located in the axial direction between the radially outer end of the base portion 61a and the radially outer end of the annular portion 62a. The discharge port 65 opens radially outwards. The pump unit 60 is rotated around the central axis J by the rotor 50, thereby drawing water into the interior from the inlet 64 and discharging it from the discharge port 65 to transport water. The water transported by the pump unit 60 also flows into the inside of the rotor housing 12.

[0044] The stator 70 is located radially outward of the rotor 50. The stator 70 is annular in shape, surrounding the rotor housing 12 and the rotor 50 on the radially outward side of the rotor housing 12. The stator 70 includes a stator core 71, an insulator 72 attached to the stator core 71, and a plurality of coils 73 attached to the stator core 71 via the insulator 72.

[0045] The stator core 71 is located radially outward of the rotor housing 12 and surrounds the rotor core 51. The stator core 71 has an annular core back 71a surrounding the rotor core 51 and a plurality of teeth 71b extending radially inward from the core back 71a. Although not shown in the figure, the plurality of teeth 71b are arranged in a line along the circumferential direction. The upper portion of the core back 71a is press-fitted from below into the circumferential wall portion 32 of the fixing member 30 and fixed thereto. In this way, the stator 70 is fixed to the fixing member 30. The lower portion of the core back 71a is located radially inward of the second annular wall portion 14 and separated from it. The lower end of the core back 71a is positioned opposite the upper side of the first annular wall portion 13 with a small gap between them. The radially inward ends of the plurality of teeth 71b are opposite the outer circumferential surface of the cylindrical portion 12b in the rotor housing 12 with a small gap between them. In other words, in this embodiment, the stator 70 is positioned in a non-contact state with the outer circumferential surface of the cylindrical portion 12b. In this embodiment, the stator 70, which is located radially outward from the outer circumferential surface of the cylindrical portion 12b, does not directly contact the rotor housing portion 12.

[0046] The insulator 72 and coil 73 protrude from the stator core 71 on both axial sides. The portions of the insulator 72 and coil 73 that protrude downward from the stator core 71 are located radially between the cylindrical portion 12b and the first annular wall portion 13 of the rotor housing 12. The portions of the insulator 72 and coil 73 that protrude downward from the stator core 71 are located radially away from the outer circumferential surface of the cylindrical portion 12b and the inner circumferential surface of the first annular wall portion 13, and are located above the bottom wall portion 11.

[0047] The substrate 80 is located above the fixing member 30 and is housed radially inside the cover member 20. The substrate 80 is plate-shaped with its surface facing axially. The substrate 80 is fixed to the support member 10 by screws to the substrate fixing parts 17a and 17b. Multiple electronic components 81 are attached to the lower surface of the substrate 80. The multiple electronic components 81 include electronic components 81 whose lower ends are inserted into the through-hole 34 from above.

[0048] A busbar 82 is fixed to the lower surface of the substrate 80, electrically connecting the coil 73 and the substrate 80. Coil lead wires 73a, which are drawn upward from the coil 73, are connected to the busbar 82. The coil lead wires 73a are drawn upward above the fixing member 30 via a through-hole 34. As shown in Figure 3, multiple busbars 82 are provided at intervals in the circumferential direction. For example, three busbars 82 are provided. In this embodiment, two coil lead wires 73a are connected to each busbar 82.

[0049] As shown in Figure 1, one end of a plurality of terminals 83 is connected to the circuit board 80. Although not shown, the other ends of the plurality of terminals 83 are provided on the connector portion 19. When an external power supply (not shown) is connected to the connector portion 19, power from the external power supply is supplied from the terminals 83 to the circuit board 80, and from the circuit board 80 to the coil 73 via the busbar 82.

[0050] According to this embodiment, the pump 100 includes a support member 10 having a base portion 10a that covers the stator 70 from below, and a rotor housing portion 12 made of a non-magnetic material that is located radially inward of the stator 70 and houses the rotor 50 inside. The rotor housing portion 12 has a lid portion 12a that covers the rotor 50 from above, and a cylindrical portion 12b that is located radially between the rotor 50 and the stator 70 and opens downward. Therefore, while the pump portion 60 is connected to the lower side of the rotor 50, the base portion 10a and the rotor housing portion 12 can seal the space between the rotor 50 and the stator 70, thereby preventing the fluid sent by the pump portion 60, i.e., water in this embodiment, from coming into contact with the stator 70.

[0051] The rotor housing 12 must be made of a non-magnetic material such as resin to prevent interference with the magnetic flux flowing between the rotor 50 and the stator 70. Therefore, the strength of the rotor housing 12 tends to be relatively lower compared to when it is made of iron or other materials. In addition, in order to obtain a relatively large rotational torque for the rotor 50, the gap between the rotor 50 and the stator 70 in the radial direction needs to be relatively small. Therefore, the radial thickness of the wall portion constituting the cylindrical portion 12b of the rotor housing 12 needs to be relatively small. Therefore, the strength of the rotor housing 12 tends to be even lower. If the stator 70 is fixed to such a rotor housing 12 from the radial outside, there is a risk of damage to the rotor housing 12. Therefore, conventionally, the entire stator 70 was covered with a resin mold, and the stator 70 was supported by the resin mold while sealing the gap between the rotor 50 and the stator 70. However, this structure had the problem that the number of steps and time required for molding the resin mold increased, which in turn increased the number of steps and time required for manufacturing the pump 100.

[0052] In contrast, according to this embodiment, the pump 100 includes a fixing member 30 located radially outside the stator 70 and surrounding the stator 70. The stator 70 is fixed to the fixing member 30, and the fixing member 30 is fixed to the support member 10. Therefore, the stator 70 can be suitably fixed to the support member 10 via the fixing member 30 without directly fixing the stator 70 to the rotor housing 12. This suppresses the application of force from the stator 70 to the rotor housing 12. Consequently, damage to the rotor housing 12 can be suppressed even without covering the entire stator 70 with a resin mold. Therefore, there is no need to cover the entire stator 70 with a resin mold, and an increase in the man-hours and time required to manufacture the pump 100 can be suppressed. As a result, according to this embodiment, the man-hours and time required to manufacture the pump 100 can be reduced while ensuring the sealing performance between the rotor 50 and the stator 70. This reduces the manufacturing cost of the pump 100. Furthermore, the fixing member 30 makes it easier to accurately position the stator 70, improving the ease of assembly of the pump 100. Also, compared to the case where the stator 70 is covered with a resin mold, advanced technology is not required in the manufacturing process. In addition, since the rotor housing 12 is prevented from receiving force from the stator 70, the cylindrical portion 12b of the rotor housing 12 can be made suitably thin, and the radial gap between the rotor 50 and the stator 70 can be suitably reduced. Therefore, the rotational torque of the rotor 50 can be suitably increased.

[0053] Furthermore, according to this embodiment, the rotor housing 12 is made of resin. Therefore, the rotor housing 12 can be made of a non-magnetic material and easily molded. On the other hand, the strength of the rotor housing 12 tends to be lower. However, as described above, in this embodiment, the fixing member 30 can be provided to suppress damage to the rotor housing 12. In this way, when the rotor housing 12 is made of resin, the effect of suppressing damage to the rotor housing 12 can be obtained more effectively. Also, according to this embodiment, the fixing member 30 is made of metal. Therefore, the stator 70 can be suitably and firmly fixed by the fixing member 30.

[0054] Furthermore, according to this embodiment, the fixing member 30 has a peripheral wall portion 32 fixed to the outer circumferential surface of the stator 70, and a fixing flange portion 33 extending radially outward from the peripheral wall portion 32. The fixing flange portion 33 is fixed to the base portion 10a from above. Therefore, the stator 70 can be firmly fixed to the peripheral wall portion 32, while the fixing member 30 can be suitably fixed to the support member 10 via the fixing flange portion 33. In addition, the fixing flange portion 33 allows the fixing member 30 to be suitably positioned axially relative to the support member 10, and the stator 70 can be suitably positioned axially relative to the support member 10.

[0055] Furthermore, according to this embodiment, the support member 10 has a fitting projection 14b that protrudes in the axial direction. The fixed flange portion 33 has a fitting hole portion 33b into which the fitting projection 14b is fitted. Therefore, the fixed member 30 can be suitably positioned radially and circumferentially with respect to the support member 10 via the fixed flange portion 33. This allows the stator 70 to be suitably positioned radially and circumferentially with respect to the support member 10.

[0056] Furthermore, when the fixing member 30 is made of sheet metal, as in this embodiment, one could consider creating a fitting projection on the fixing flange portion 33 by extruding a part of the plate-shaped fixing flange portion 33. However, in this case, it is difficult to increase the protruding height of the fitting projection. Therefore, by providing the fitting projection 14b on the support member 10 as in this embodiment, it is easier to increase the protruding height of the fitting projection 14b and to suitably fit the fitting projection 14b with the fitting hole portion 33b.

[0057] Furthermore, according to this embodiment, the fixing member 30 has a top wall portion 31 fixed to the upper side of the lid portion 12a. Therefore, the rotor housing portion 12 can be reinforced by the top wall portion 31. This further suppresses damage to the rotor housing portion 12.

[0058] Furthermore, according to this embodiment, the stator 70 is positioned in a non-contact manner with the outer circumferential surface of the cylindrical portion 12b. Therefore, the direct application of force from the stator 70 to the rotor housing portion 12 can be more effectively suppressed. Consequently, damage to the rotor housing portion 12 can be more effectively suppressed.

[0059] Furthermore, according to this embodiment, the pump 100 is a water pump that sends water. Water has relatively low viscosity and is more difficult to seal than oil, etc. Therefore, in order to effectively suppress water from coming into contact with the stator 70, conventional water pumps employ a structure in which the entire stator 70 is covered with a resin mold to seal it. As described above, the structure of the pump 100 in this embodiment has the effect of making the manufacturing of the pump 100 easier compared to such a structure in which the entire stator 70 is covered with a resin mold. In other words, the conventional structure in which the entire stator 70 is covered with a resin mold is a structure that is easily adopted in water pumps, while the structure of this embodiment is a more useful structure when applied to a water pump.

[0060] Furthermore, for example, in the case where the fixed shaft 40 is fixed to the rotor housing 12 as in this embodiment, if the fixed shaft 40 is fixed by directly tightening a screw, there is a risk that fluid may leak from inside the rotor housing 12 to the stator 70 through the gap between the fixed shaft 40 and the screw. However, if the fixed shaft 40 is not fixed directly with a screw, there is a risk that the fixing of the fixed shaft 40 will become unstable.

[0061] In contrast, according to this embodiment, the lid portion 12a of the rotor housing portion 12 has a retaining portion 12c that holds the upper end of the fixed shaft 40. The upper end of the fixed shaft 40 is provided with a hole portion 43 that is recessed downwards. The retaining portion 12c has a projection portion 12d located in at least a part of the hole portion 43. A screw 92 is tightened into the lid portion 12a from above. At least a part of the screw 92 is tightened into the projection portion 12d. As a result, the projection portion 12d is pushed open by the screw 92 and pressed against the inner circumferential surface of the hole portion 43. This improves the strength of the projection portion 12d and firmly fixes the projection portion 12d to the fixed shaft 40. Therefore, the fixed shaft 40 is firmly fixed to the lid portion 12a. As a result, problems such as the fixed shaft 40 tilting can be suppressed, and the rotor 50 can be suitably supported by the fixed shaft 40.

[0062] On the other hand, the screw 92 is not directly tightened into the fixed shaft 40, and a projection 12d is provided between the screw 92 and the fixed shaft 40. As a result, the space between the screw 92 and the fixed shaft 40 is sealed by the projection 12d, which prevents the fluid that has flowed into the rotor housing 12 from leaking out of the rotor housing 12 through the engagement portion of the screw 92. Thus, according to this embodiment, it is possible to improve the fixing strength of the fixed shaft 40 while suppressing the leakage of fluid to the stator 70. In addition, since the fluid does not come into contact with the screw 92, it is possible to prevent problems such as corrosion of the screw 92.

[0063] Furthermore, according to this embodiment, the top wall portion 31 of the fixing member 30 is fixed to the upper side of the lid portion 12a by a screw 92 that is tightened into the projection portion 12d. Therefore, the fixing shaft 40 is firmly fixed to the rotor housing portion 12 by the screw 92, while the rotor housing portion 12 can be reinforced by the top wall portion 31 as described above.

[0064] Furthermore, according to this embodiment, the rotor housing 12 is made of resin, and the screw 92 is a self-tapping screw. Therefore, the screw 92 can be directly and suitably fastened to the lid 12a of the resin rotor housing 12. This eliminates the need, for example, to embed a metal nut member in the rotor housing 12, thereby suppressing an increase in the number of parts of the pump 100.

[0065] The present invention is not limited to the embodiments described above, and other configurations and methods may be adopted within the scope of the technical idea of ​​the present invention. The material constituting the support member is not particularly limited as long as it is nonmagnetic. Any type of screw may be used to fasten the lid. Screws may not be fastened to the lid. The material constituting the fixing member is not particularly limited. The fixing flange portion may have a fitting projection that protrudes in the axial direction, and the support member may have a fitting hole portion into which the fitting projection is fitted. The fitting projection and fitting hole portion may not be provided. The fixing member may be fixed to the support member by means other than screw fixing. The fixing member may be fixed to the support member by heat crimping a part of the support member, or by ultrasonic welding a part of the support member. The fixing member may not have a top wall portion. The stator may be in contact with the rotor housing portion. The fixing shaft may not be provided.

[0066] The applications of the pump to which the present invention is applied are not particularly limited. The pump may be mounted on any equipment. For example, the pump may be mounted on a vehicle. The pump may be a pump that delivers any fluid. The pump may be an oil pump that delivers oil. In addition, the configurations described herein can be combined as appropriate, within the limits of what is not inconsistent with each other. [Explanation of Symbols]

[0067] 10...Support member, 10a...Base, 12...Rotor housing, 12a...Lid, 12b...Cylindrical part, 14b...Fitting projection, 30...Fixing member, 31...Top wall, 32...Peripheral wall, 33...Fixing flange, 33b...Fixing hole, 43...Hole, 50...Rotor, 60...Pump section, 70...Stator, 100...Pump, J...Central axis

Claims

1. a rotor rotatable about a central axis; a stator positioned radially outside the rotor and surrounding the rotor; a pump portion connected to one axial side of the rotor; a support member having a base portion that covers the stator from one axial side, and a rotor accommodating portion that is made of a non-magnetic material and is located radially inside the stator and accommodates the rotor therein; a fixing member positioned radially outside the stator and surrounding the stator; Equipped with The rotor accommodating portion is a cover portion that covers the rotor from the other axial side; a cylindrical portion located between the rotor and the stator in the radial direction and opening to one axial side; and the stator is fixed to the fixed member, The fixed member is fixed to the support member.

2. the rotor accommodating portion is made of resin, The pump of claim 1 , wherein the stationary member is made of metal.

3. The fixing member is a peripheral wall portion fixed to an outer peripheral surface of the stator; a fixed flange portion extending radially outward from the peripheral wall portion; and The pump according to claim 1 or 2, wherein the fixed flange portion is fixed to the base portion from the other axial side.

4. One of the fixing flange portion and the support member has a fitting protrusion that protrudes in the axial direction, The pump according to claim 3 , wherein the other of the fixed flange portion and the support member has a fitting hole into which the fitting projection is fitted.

5. The pump according to claim 1 , wherein the fixing member has a top wall portion fixed to the other axial side of the lid portion.

6. The pump according to claim 1 , wherein the stator is disposed in a non-contact state with an outer peripheral surface of the cylindrical portion.

7. The pump according to any one of claims 1 to 6, which is a water pump for pumping water.

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