Pump device

Abstract

To restrain insufficient welding strength when forming a pump chamber by welding a case to a housing on a motor side.SOLUTION: In a pump device 1, a pump chamber is formed between a housing 10 for a motor 3 and a case 2. The case 2 is provided with a suction port and a discharge port facing one side L1 in an axial direction. The housing 10 comprises a first flange part 16 protruding to an outer peripheral side from a trunk part 14 covering an outer periphery of a stator, and a reinforcing rib 46 connecting an outer peripheral surface of the trunk part 14 and the first flange part 16. The case 2 and the housing 10 are welded by welding a welding rib provided in a second fixing surface of the case 2 to a welding concave part provided in a first fixing surface of the first flange part 16. The reinforcing rib 46 overlaps with the welding rib and the welding concave part when viewed from the axial direction.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a pump device that sucks fluid into a pump chamber and discharges it by rotating an impeller. [Background technology]

[0002] Patent Documents 1 and 2 describe a pump device that circulates cooling water. In the pump device of Patent Document 1, a pump chamber is formed between a housing (a resin sealing member) that covers an annular stator and a case that is fixed to an end of the housing. The impeller rotates integrally with a rotor that is disposed on the inner circumference of the stator. The case includes a suction pipe that is connected to the radial center of the pump chamber, and a discharge pipe that is connected to the outer circumference of the pump chamber.

[0003] In Patent Document 1, a pump chamber is formed by abutting an annular flange provided at an end of a case against an annular flange provided at an end of a housing (resin sealing member) in the axial direction and fixing them by vibration welding. The welded portion extends in a circular shape along the outer periphery of the annular flange. Therefore, the weld strength is uniform at any position in the circumferential direction, and the weld strength is less likely to vary.

[0004] In a pump device having a fluid intake port in the center of a pump chamber and a fluid discharge port on the outer periphery of the pump chamber, the pump chamber may have a shape in which the radial width of the flow path increases toward one side in the circumferential direction (for example, an involute shape). Patent Document 2 describes a pump device having an involute shaped pump chamber. In the pump device of Patent Document 2, the housing (pump base) and the case (pump mounting portion) are fastened together by bolts on the outer periphery of the pump chamber.

[0005] In the pump device of Patent Document 2, the case that defines a pump chamber between itself and the housing (pump base) is a member of the pump mounting site where the pump device is installed, and the pump device is fixed via this member. The inlet opens in the center of the involute shape in the direction of the rotation axis, and the outlet opens in the same direction as the inlet, on the outer periphery of the involute shape. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2022-020102 [Patent Document 2] JP 2010-090776 A Summary of the Invention [Problem to be solved by the invention]

[0007] In a pump device in which the housing and case constituting the pump chamber are made of resin and joined by welding as in Patent Document 1, durability decreases if the weld strength of the welded portion between the housing and case is insufficient.

[0008] For example, as in Patent Document 2, when a pump device is attached to a mating member not through a housing on the motor side but through a case provided with an intake port and a discharge port, or when the shape of the pump chamber is non-circular (e.g., an involute shape), there may be variations in the weld strength at the welded portion between the housing and the case and in the stress applied to the welded portion. As a result, there may be areas where the weld strength is insufficient.

[0009] In view of the above problems, the object of the present invention is to provide a motor-side housing and The object of the present invention is to prevent the occurrence of a portion where the weld strength is insufficient when a pump chamber is formed by welding a case provided with an inlet and a discharge port. [Means for solving the problem]

[0010] In order to achieve the above object, a pump device of the present invention includes a rotor and a stator surrounding an outer periphery of the rotor, a housing sealing the stator, a case including a pump chamber forming portion that is fitted over the housing from one side in an axial direction along a rotation axis of the rotor to form a pump chamber between the housing and the case, and an impeller that is disposed in the pump chamber and rotates integrally with the rotor, wherein the housing includes a first partition portion that covers one side of the axial direction of the stator, a body portion that covers the outer periphery of the stator, and a housing that is fitted over the housing from one side in the axial direction. the first flange portion protruding toward the outer periphery from the body portion, and a reinforcing rib connecting the outer periphery of the body portion and the first flange portion, the first flange portion having a first fixed surface facing one side in the axial direction, the pump chamber forming portion having a second fixed surface opposite to the first fixed surface, one of the first fixed surface and the second fixed surface having a welding rib, and the other of the first fixed surface and the second fixed surface having a welding recess to which the welding rib is welded, and the reinforcing rib overlaps with the welding rib and the welding recess when viewed from the axial direction.

[0011] According to the present invention, the housing, to which the case is welded to form a pump chamber between the case and the housing, is provided with a reinforcing rib that connects the first flange portion having a welded portion (welding rib or welding recess) and the body portion, and the welded portion overlaps the reinforcing rib. Therefore, the reinforcing rib can reinforce the portion where the weld strength between the housing and the case is insufficient, thereby suppressing a decrease in durability due to insufficient weld strength. For example, when there is variation in weld strength or in the stress applied to the welded portion due to the shape of the pump chamber or the mounting structure of the pump device, the reinforcing rib can reinforce the portion where the weld strength is insufficient.

[0012] In the present invention, the pump chamber forming portion includes an intake port provided at the center of the pump chamber in the radial direction and an outlet port provided on the outer periphery of the pump chamber, and when the intake port and the outlet port open to one side in the axial direction, it is preferable that the reinforcing rib is disposed at an angular position where the outlet port is provided. In this manner, in a configuration in which the outlet port faces one side in the axial direction, the direction and magnitude of the fluid pressure applied to the inner periphery of the pump chamber near the outlet port differs from other parts, and there is a risk that the required welding strength cannot be ensured. Therefore, by providing a reinforcing rib in this part, it is possible to reinforce the part where the welding strength is insufficient.

[0013] In the present invention, the shape of the pump chamber as viewed from the axial direction is such that the width of the flow passage extending in the circumferential direction around the outer periphery of the impeller increases toward one side in the circumferential direction, and the welding rib extends along the outer shape of the pump chamber as viewed from the axial direction, and when the angular position at which the width of the flow passage is the largest is defined as a first angular position and the angular position at which the width of the flow passage is the smallest is defined as a second angular position, it is preferable that the discharge port is provided at the first angular position, and the reinforcing rib is provided in a first angular range from the first angular position to the second angular position on the one side of the circumferential direction of the first angular position. In this way, in a pump chamber in which the width of the flow passage increases toward the discharge port, a portion (e.g., a portion that is linear) where the outer shape of the pump chamber is not arc-shaped is formed in the range (first angular range) from the downstream end position (first angular position) of the flow passage back to the upstream end position (second angular position). Therefore, there is a risk that the welding strength cannot be ensured at this portion, so by providing a reinforcing rib at this portion, the portion where the welding strength is insufficient can be reinforced.

[0014] In the present invention, the housing preferably includes a plurality of reinforcing ribs extending in parallel to a first direction perpendicular to the axial direction from a plurality of circumferential positions on the body. In this way, if the mold for molding the housing is structured to open in the first direction, the reinforcing ribs can be molded without using a slide mold that slides in a direction intersecting the first direction (mold opening direction). Therefore, the structure of the molding mold does not become complicated in order to provide the reinforcing ribs. This can be avoided.

[0015] In the present invention, it is preferable that one of the first and second fixing surfaces includes an additional welding rib arranged on the outer periphery side of the welding rib, the other of the first and second fixing surfaces includes an additional welding recess arranged on the outer periphery side of the welding recess, and the reinforcing rib is arranged at an angle position where the additional welding rib and the additional welding recess are provided. In this way, the area where the reinforcing rib is arranged can be further reinforced by the additional welding portion. Therefore, the reinforcing effect can be enhanced.

[0016] In the present invention, it is preferable that the reinforcing rib extends from a position overlapping the welding rib as viewed from the axial direction to a position overlapping the additional welding rib as viewed from the axial direction. In this way, by providing the reinforcing rib so as to straddle two welding portions, the reinforcing effect can be enhanced.

[0017] In the present invention, it is preferable that the case includes an attachment portion disposed on the outer periphery of the pump chamber forming portion, the pump chamber forming portion includes a side wall portion surrounding the outer periphery of the pump chamber and a protrusion portion protruding from the side wall portion to the outer periphery, the attachment portion is disposed on the outer periphery of the protrusion portion, the second fixing surface includes a first region consisting of an end face of the side wall portion on the other side in the axial direction and a second region consisting of an end face of the protrusion portion on the other side in the axial direction, the welding rib or the welding recess is provided in the first region, and the additional welding rib or the additional welding recess is provided in the second region. In this way, when an attachment portion for fixing the pump device to a mating member is provided on the case, the attachment portion can be reinforced by the protrusion portion, and a space can be secured for arranging the additional welding rib or additional welding recess for reinforcement by utilizing the protrusion portion.

[0018] In the present invention, it is preferable that the reinforcing rib overlaps with the linearly extending portion of the welding rib when viewed from the axial direction. The linearly extending portion of the welding rib is more likely to collapse than the arcuately extending portion, making it difficult to ensure welding strength. Therefore, by providing a reinforcing rib at this portion, it is possible to reinforce the portion where the welding strength is insufficient. Effect of the Invention

[0019] According to the present invention, the housing, to which the case is welded to form a pump chamber between the case and the housing, is provided with a reinforcing rib that connects the first flange portion having the welded portion (welding rib or welding recess) to the outer circumferential surface of the body portion, and the welded portion overlaps the reinforcing rib. Therefore, the reinforcing rib can reinforce the portion where the weld strength between the housing and the case is insufficient, thereby suppressing a decrease in durability due to insufficient weld strength. For example, when the shape of the pump chamber or the mounting structure of the pump device causes variation in the weld strength or variation in the stress applied to the welded portion, the reinforcing rib can reinforce the portion where the weld strength is insufficient. [Brief description of the drawings]

[0020] [Figure 1] 1 is a cross-sectional view of a pump device to which the present invention is applied. [Diagram 2] 13 is a plan view of the case as viewed from the other axial side. FIG. [Diagram 3] 11 is a perspective view of the case as viewed from the other axial side. FIG. [Figure 4] FIG. 2 is an exploded perspective view of a rotor and a housing as viewed from one side in the axial direction. [Diagram 5] 4 is a perspective view of the pump device as viewed from the other axial side. FIG. [Figure 6] 10 is an explanatory diagram showing the arrangement of the welding ribs, the additional welding ribs, and the reinforcing ribs. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, a pump device 1 according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the axial direction refers to the direction in which the rotation axis L of the motor 3 extends (along the rotation axis L). The radial direction refers to the radial direction centered on the rotation axis L, and the circumferential direction refers to the direction of rotation centered on the rotation axis L. The direction in which the rotation axis L extends is referred to as the axial direction, with one side of the axial direction referred to as L1 and the other side of the axial direction referred to as L2. One side of the circumferential direction is referred to as R1, and the other side of the circumferential direction is referred to as R2.

[0022] (Overall composition) 1 is a cross-sectional view of a pump device 1 to which the present invention is applied, the cross-sectional view being obtained by cutting the pump device 1 along a plane including a rotation axis L. As shown in Fig. 1, the pump device 1 has a case 2 provided with a suction port 21 and a discharge port 22 that open on one axial side L1, a motor 3 disposed on the other axial side L2 relative to the case 2, and an impeller 4 disposed in a pump chamber 20 provided between a housing 10 of the motor 3 and the case 2.

[0023] The impeller 4 is driven to rotate about a rotation axis L by the motor 3. In the pump device 1 of this embodiment, the fluid flowing through the pump chamber 20 is liquid. The fluid supplied to the pump chamber 20 from an intake port 21 provided in the radial center of the case 2 moves circumferentially through the pump chamber 20 as the impeller 4 rotates, and is discharged from an exhaust port 22 provided on the outer periphery of the pump chamber 20. The intake port 21 and the exhaust port 22 open on an end face of the case 2 on one side L1 in the axial direction.

[0024] The motor 3 includes an annular stator 5, a rotor 6 arranged inside the stator 5, a support shaft 7 that rotatably supports the rotor 6, a substrate 8 arranged on the other axial side L2 of the stator 5, a housing 10 that covers the stator 5, and a resin cover 9 that covers the substrate 8. The support shaft 7 is made of metal or ceramic. The housing 10 is a resin sealing member that covers the stator 5 from both radial and axial sides. The housing 10 is made of polyphenylene sulfide (PPS). The stator 5 is integrated with the housing 10 by insert molding.

[0025] The stator 5 includes an annular stator core 51, an insulator 52 overlapping the stator core 51 from one axial side L1, an insulator 53 overlapping the stator core 51 from the other axial side L2, and a plurality of coils 50 wound around a plurality of salient poles provided on the stator core 51 via the insulators 52 and 53. The motor 3 is a three-phase motor. Thus, the plurality of coils 50 are constituted by a U-phase coil, a V-phase coil, and a W-phase coil.

[0026] The housing 10 is a partition member having a first partition portion 11 covering one axial side L1 of the stator 5, a second partition portion 12 covering the inner circumferential side of the stator 5, and a bottom wall 13 provided at an end of the second partition portion 12 on the other axial side L2. The housing 10 also includes a cylindrical body portion 14 covering the stator 5 from the radial outside, a cylindrical connector housing 15 extending radially outward from the body portion 14 on the radial outside of the stator 5, and a first flange portion 16 expanding radially outward from an end of the body portion 14 on the one axial side L1. The first flange portion 16 is connected to the connector housing 15.

[0027] The cover 9 is fixed to the end of the other side L2 of the body 14 of the housing 10. A circular opening 90 is provided in the center of the cover 9, and the opening 90 is covered from one side L1 in the axial direction by a metallic heat dissipation member 91. A metallic winding terminal 55 that penetrates the bottom wall 13 of the housing 10 from the stator 5 and protrudes to the other side L2 in the axial direction is connected to the board 8 arranged between the cover 9 and the bottom wall 13 of the housing 10. When an external connector (not shown) for power supply is connected to the connector housing 15, a driving current generated by a circuit mounted on the board 8 is supplied to each coil 50 via the winding terminal 55. As a result, the rotor 6 and the impeller 4 rotate together, the inside of the pump chamber 20 becomes negative pressure, and the fluid is pumped out from the suction port 21. The fuel is sucked into the pump chamber 20 and discharged from the discharge port 22.

[0028] The rotor 6 includes a rotor member 60 made of resin, and a cylindrical magnet 61 held by the rotor member 60. The rotor member 60 includes a cylindrical portion 62 extending in the axial direction, and a disk-shaped flange portion 63 extending from an end of one side L1 in the axial direction of the cylindrical portion 62 toward the outer periphery. The magnet 61 is fixed to the outer periphery of the cylindrical portion 62. The magnet 61 faces the stator 5 on the radially inner side. The magnet 61 is made of, for example, a neodymium bonded magnet.

[0029] A radial bearing 70 is held inside the cylindrical portion 62. The rotor 6 is rotatably supported by the support shaft 7 via the radial bearing 70. An end of the support shaft 7 on the other axial side L2 is held in a shaft hole 71 formed in the bottom wall 13 of the housing 10. The case 2 has three support parts 72 extending from the inner circumferential surface of the suction port 21 to the motor 3 side, and a tubular part 73 is provided at the tip of the support part 72 into which an end of the support shaft 7 on one axial side L1 fits. A thrust bearing 74 attached to the end of the support shaft 7 on one axial side L1 is disposed between the tubular part 73 and the radial bearing 70.

[0030] A plurality of blades 64 protrude from the flange portion 63 of the rotor member 60 toward one side L1 in the axial direction, and a resin plate 65 is fixed to the tip of the blades 64 from the one side L1 in the axial direction. The plurality of blades 64 extend radially outward while curving in an arc, and are arranged at equal angular intervals. The flange portion 63, the blades 64, and the plate 65 constitute the impeller 4. The three support portions 72 provided on the case 2 are arranged inside a circular hole 66 provided in the center of the plate 65, and are connected to a tube portion 73 arranged inside the cylindrical portion 62 of the rotor member 60.

[0031] (case) FIG. 2 is a plan view of the case 2 as viewed from the other axial side L2. FIG. 3 is a perspective view of the case 2 as viewed from the other axial side L2. As shown in FIG. 1, the case 2 is placed over the housing 10 from one axial side L1. As shown in FIGS. 1, 2, and 3, the case 2 includes a pump chamber forming portion 23 that forms a pump chamber 20 between the case 2 and the housing 10, and a mounting portion 24 with a hole that is disposed on the outer periphery of the pump chamber forming portion 23. The pump device 1 is fixed to a mating member (not shown) via three mounting portions 24 provided on the case 2. At that time, the suction port 21 and the discharge port 22 provided on the case 2 are positioned at positions that allow connection to flow paths such as holes and tubes provided on the mating member.

[0032] 1, 2, and 3, the pump chamber forming portion 23 includes an upper wall portion 25 through which the suction port 21 and the discharge port 22 penetrate in the axial direction, and a side wall portion 26 that protrudes from the upper wall portion 25 to the other axial side L2 and surrounds the outer periphery of the pump chamber 20. The upper wall portion 25 is provided with a circular first recess 27 that is recessed to one axial side L1 about the rotation axis L, and a second recess 28 that is recessed to one axial side L1 on the outer periphery of the first recess 27. The second recess 28 has a substantially semicircular cross-sectional shape when cut in the radial direction, and the side wall portion 26 extends along the outer periphery of the second recess 28.

[0033] As shown in Fig. 1, in the pump chamber 20, the upper part of the impeller 4 is disposed in the first recess 27, and on the outer periphery of the impeller 4, a flow passage F surrounded by the second recess 28 and the side wall portion 26 extends in the circumferential direction. As shown in Figs. 2 and 3, the second recess 28 has a shape in which the radial width increases toward one side R1 in the circumferential direction. Therefore, in the pump chamber 20, the width of the flow passage F extending in the circumferential direction around the outer periphery of the impeller 4 increases toward one side R1 in the circumferential direction. An example of such a shape is an involute shape.

[0034] As shown in FIG. 2, the second recess 28 has an end portion on one circumferential side R1 at a first angular position T1. The flow passage F extends circumferentially around the inner periphery of the pump chamber 20 from the second angular position T2 to the one circumferential side R1 to a first angular position T1. The second angular position T2 is the angular position where the width of the flow passage F is smallest, and the first angular position T1 is the angular position where the width of the flow passage F is largest.

[0035] 2 and 3, the discharge port 22 opens at the bottom of the second recess 28 at the first angular position T1. In a range from one circumferential side R1 of the first angular position T1 to the second angular position T2 (hereinafter referred to as the first angular range θ), a convex portion 29 that protrudes from the inner circumferential surface of the side wall portion 26 and the bottom surface of the second recess 28 toward the inside of the pump chamber 20 is provided. Therefore, the fluid flowing through the pump chamber 20 to one circumferential side R1 collides with the convex portion 29 at the first angular position T1 and flows toward the discharge port 22.

[0036] 2 and 3, the pump chamber forming portion 23 has two protrusions 31, 32 that protrude from the side wall portion 26 to the outer periphery. The protrusion 31 is provided in the first angle range θ, and is disposed on the outer periphery side of the discharge port 22 and the convex portion 29. The protrusion 32 is provided at a position opposite the protrusion 31 in the radial direction. Two of the three mounting portions 24 provided on the case 2 are disposed on the outer periphery side of the protrusions 31, 32. Therefore, the mounting portion 24 is reinforced by the protrusions 31, 32.

[0037] (welded part) Fig. 4 is an exploded perspective view of the rotor 6 and the housing 10 as viewed from one side L1 in the axial direction. As shown in Fig. 4, the first flange portion 16 is provided around the entire circumference of the body portion 14. The outer shape of the first flange portion 16 approximately matches the outer shape of the pump chamber forming portion 23 as viewed from the axial direction. The first flange portion 16 has protruding portions 17 and 18 which overlap with two protruding portions 31 and 32 provided on the pump chamber forming portion 23 as viewed from the axial direction.

[0038] As shown in Figs. 1 and 4, the first flange portion 16 has a first fixed surface 19 facing one side L1 in the axial direction. As shown in Figs. 1 and 3, the pump chamber forming portion 23 has a second fixed surface 33 which is an end face of the other side L2 in the axial direction of the side wall portion 26 and the protruding portions 31, 32. The first fixed surface 19 and the second fixed surface 33 face each other in the axial direction. The case 2 and the housing 10 are joined by welding a welding rib 42 provided on the second fixed surface 33 to a welding recess 41 provided on the first fixed surface 19 by vibration welding. A welding portion 40 (see Fig. 1) in which the welding rib 42 is welded to the welding recess 41 surrounds the entire circumference of the pump chamber 20.

[0039] When the case 2 and the housing 10 are joined by vibration welding, for example, the pump chamber forming portion 23 is overlapped with the first flange portion 16 from one axial side L1, and the first flange portion 16 is pressed from the other axial side L2. Since the axial height of the welding rib 42 is greater than the depth of the welding recess 41, the tip of the welding rib 42 inserted into the welding recess 41 is crushed by the bottom surface of the welding recess 41. Since the radial thickness of the welding rib 42 is smaller than the width of the welding recess 41, welding burrs (not shown) are accommodated in the gap around the welding rib 42 inserted into the welding recess 41.

[0040] Furthermore, the first flange portion 16 is provided with an additional welding recess 43 on the outer periphery of the welding recess 41 on the first fixing surface 19, and the case 2 is provided with an additional welding rib 44 on the outer periphery of the welding rib 42 on the second fixing surface 33. The additional welding recess 43 and the additional welding rib 44 are each provided at two locations on opposite sides in the radial direction. When the case 2 is joined to the housing 10 by vibration welding, additional welds formed by welding the additional welding recess 43 and the additional welding rib 44 to each other are formed at two locations on opposite sides in the radial direction on the outer periphery of the welded portion 40. This reinforces the welded portion 40 at two locations.

[0041] 4, the welding recess 41 extends in the first fixing surface 19 in a shape that follows the outer shape of the pump chamber 20 when viewed from the axial direction. One of the two additional welding recesses 43 extends along the outer circumferential edge of the protruding portion 17, and both ends of the additional welding recess 43 are connected to the welding recess 41. The other additional welding recess 43 is provided in the protruding portion 18. In the protruding portion 18, the additional welding recess 43 extends over the entire protruding portion 18 and is integrated with the welding recess 41.

[0042] 2 and 3, the welding rib 42 extends on the second fixing surface 33 in a shape that follows the outer shape of the pump chamber 20 when viewed from the axial direction. More specifically, the welding rib 42 includes a curved portion 420 that extends while curving from the second angular position T2 to one circumferential side R1 to the first angular position T1, a first straight portion 421 that bends toward the inner circumferential side at the first angular position T1 and extends linearly, and a second straight portion 422 that bends on the one circumferential side R1 of the first straight portion 421 in a direction forming an obtuse angle with the first straight portion 421 and extends linearly to the second angular position T2.

[0043] In this manner, in this embodiment, by providing the welded portion 40 along the outer shape of the pump chamber 20, a part of the welded portion 40 extends linearly without being curved in the first angle range θ. The first linear portion 421 and the second linear portion 422 of the welded rib 42 are more likely to collapse than the curved portion 420 when subjected to fluid pressure. Therefore, the welded portion 40 has the lowest weld strength at the portion where the first linear portion 421 and the second linear portion 422 are welded to the welded recess 41. One of the two additional welded portions is disposed on the outer periphery of the first reinforced portion, with the first linear portion 421 and the second linear portion 422 as the first reinforced portion, and reinforces the portion of the welded portion 40 with the lowest weld strength.

[0044] Here, it was confirmed by analysis that when additional welded portions are provided on the outer periphery of the first straight portion 421 and the second straight portion 422, the portion with the lowest weld strength is the portion radially opposite the first straight portion 421 and the second straight portion 422. Therefore, the portion radially opposite the first straight portion 421 and the second straight portion 422 is set as the second reinforced portion, and additional welded portions (additional welding recess 43, additional welding rib 44) are also arranged on the outer periphery of the second reinforced portion.

[0045] As shown in FIG. 2 and FIG. 3, the second fixing surface 33 includes a first region 34 that is an end face of the other side L2 in the axial direction of the side wall portion 26 and surrounds the outer periphery of the pump chamber 20, and a welding rib 42 is arranged in the first region 34. The second fixing surface 33 also includes two second regions 35, 36 that are end faces of the other side L2 in the axial direction of the protruding portions 31, 32 and are provided on the outer periphery side of the first region 34. The second region 35 extends to the outer periphery side of the first straight portion 421 and the second straight portion 422. The second region 36 extends to the outer periphery side of the curved portion 420 at a position radially opposite to the first straight portion 421 and the second straight portion 422. An additional welding rib 44 is arranged in the second regions 35, 36.

[0046] The additional welding ribs 44 extend continuously along the outer periphery of the second regions 35, 36. Each additional welding rib 44 extends linearly toward the outer periphery of the welding rib 42, then curves in the opposite direction, and extends linearly toward the welding rib 42. In other words, each of the two additional welding ribs 44 includes first portions 441 at two circumferentially separated locations, the first portions 441 extending linearly in a direction intersecting the outer periphery of the welding rib 42. The outer periphery side ends of the two first portions 441 are connected by second portions 442 that extend circumferentially while curving.

[0047] In this embodiment, a gap S is provided between the first portion 441 of the additional welding rib 44 and the welding rib 42 disposed on the inner periphery thereof, and the additional welding rib 44 is not connected to the welding rib 42. By providing the gap S between the additional welding rib 44 and the welding rib 42, a space is secured to accommodate welding burrs generated when the additional welding rib 44 is welded.

[0048] (Reinforcement rib) FIG. 5 is a perspective view of the pump device 1 as viewed from the other side L2 in the axial direction. In the following description, the first direction X is a direction perpendicular to the axial direction, and the second direction is a direction perpendicular to the axial direction and perpendicular to the first direction X. As shown in FIGS. 4 and 5, the housing 10 has reinforcing ribs 46 at multiple positions that connect the body 14 and the first flange portion 16. The reinforcing ribs 46 protrude in the first direction X from the outer circumferential surface of the body 14 and are connected to the surface of the other side L2 in the axial direction of the first flange portion 16. Each reinforcing rib 46 has a shape in which the radial length increases toward the one side L1 in the axial direction, and extends to the outer circumferential edge of the first flange portion 16. The reinforcing ribs 46 are arranged in the second direction Y and extend parallel to the first direction X. In this embodiment, a plurality of reinforcing ribs 46 protrude in parallel from the outer peripheral surface of the body 14 on one side in the first direction X (the side on which the protrusions 31 and 17 are provided) and on the other side in the first direction X (the side on which the protrusions 32 and 18 are provided).

[0049] 6 is an explanatory diagram showing the arrangement of the welding rib 42, the additional welding rib 44, and the reinforcing rib 46, and is a partial cross-sectional view of the pump device 1 as viewed from the other axial side L2. Each of the multiple reinforcing ribs 46 overlaps with the welding rib 42 as viewed from the axial direction. Of the multiple reinforcing ribs 46, one reinforcing rib 461 connected to the protruding portion 17 of the first flange portion 16 and two reinforcing ribs 462, 463 connected to the protruding portion 18 of the first flange portion 16 each overlap with both the welding rib 42 and the additional welding rib 44 as viewed from the axial direction.

[0050] The reinforcing rib 461 connected to the protruding portion 17 of the first flange portion 16 is disposed in the first angle range θ, and is provided at a position overlapping with the discharge port 22 when viewed from the axial direction. The reinforcing rib 461 extends from a position overlapping with the second straight portion 422 of the welding rib 42 to a position overlapping with the additional welding rib 44 extending along the outer circumferential edge of the protruding portion 17.

[0051] The two reinforcing ribs 462, 463 connected to the protruding portion 18 of the first flange portion 16 are disposed at positions on the radially opposite sides with respect to the first angle range θ. The reinforcing ribs 462, 463 extend from a position overlapping in the axial direction with the second reinforced portion of the welding rib 42 (i.e., the portion on the radially opposite side with respect to the first straight portion 421 and the second straight portion 422) to a position overlapping with the additional welding rib 44 extending along the outer circumferential edge of the protruding portion 18.

[0052] (Main effects of this embodiment) As described above, the pump device 1 of this embodiment includes the rotor 6, the stator 5 surrounding the outer periphery of the rotor 6, the housing 10 sealing the stator 5, the case 2 including the pump chamber forming portion 23 that covers the housing 10 from one side L1 in the axial direction along the rotation axis L of the rotor 6 to form the pump chamber 20 between the housing 10, and the impeller 4 that is disposed in the pump chamber 20 and rotates integrally with the rotor 6. The housing 10 includes a first partition portion 11 that covers the one side L1 in the axial direction of the stator 5, a body portion 14 that covers the outer periphery of the stator 5, a first flange portion 16 that protrudes from the body portion 14 to the outer periphery side, and a reinforcing rib 46 that connects the outer periphery of the body portion 14 and the first flange portion 16. The first flange portion 16 includes a first fixing surface 19 facing the one side L1 in the axial direction, and the pump chamber forming portion 23 includes a second fixing surface 33 that faces the first fixing surface 19. The second fixing surface 33 has a welding rib 42, the first fixing surface 19 has a welding recess 41 to which the welding rib 42 is welded, and the reinforcing rib 46 overlaps with the welding rib 42 and the welding recess 41 when viewed from the axial direction.

[0053] In this embodiment, the housing 10, which forms the pump chamber 20 between itself and the case 2, is provided with a reinforcing rib 46 that connects the first flange portion 16, which has a welding point, to the body portion 14, and the reinforcing rib 46 overlaps the welding point. Therefore, the reinforcing rib 46 can reinforce the portion where the welding strength between the housing 10 and the case 2 is insufficient, thereby suppressing a decrease in durability due to insufficient welding strength. For example, when there is variation in the welding strength or the stress applied to the welding point due to the shape of the pump chamber 20 or the mounting structure of the pump device 1, the reinforcing rib 46 can be used to In addition, since the reinforcing rib 46 can suppress deformation of the first flange portion 16, it is possible to suppress a decrease in the welding strength caused by the deformation of the first flange portion 16, which would otherwise cause the welding rib 42 to be unable to sufficiently contact the welding recess 41.

[0054] In this embodiment, the pump chamber forming portion 23 of the case 2 includes an intake port 21 provided at the center in the radial direction of the pump chamber 20, and an outlet port 22 provided on the outer periphery of the pump chamber 20. The intake port 21 and the outlet port 22 open to one side L1 in the axial direction, and the reinforcing rib 46 is disposed at an angular position where the outlet port 22 is provided. In this configuration in which the outlet port 22 faces one side L1 in the axial direction, the direction and magnitude of the fluid pressure applied to the inner periphery of the pump chamber 20 in the vicinity of the outlet port 22 differs from other portions, and there is a risk that the required welding strength cannot be ensured. Therefore, by providing the reinforcing rib 46 in this portion, it is possible to reinforce the portion where the welding strength is insufficient.

[0055] In this embodiment, the shape of the pump chamber 20 as viewed from the axial direction is such that the width of the flow passage F extending in the circumferential direction around the outer periphery of the impeller 4 increases toward one side R1 in the circumferential direction, and the welding rib 42 extends along the outer shape of the pump chamber 20 as viewed from the axial direction. When the angular position at which the width of the flow passage F is the largest is defined as a first angular position T1, and the angular position at which the width of the flow passage F is the smallest is defined as a second angular position T2, the discharge port 22 is provided at the first angular position T1, and the reinforcing rib 46 is provided in a first angular range θ from the one circumferential side R1 of the first angular position T1 to the second angular position T2. ​​In this manner, in the pump chamber 20 having a shape in which the width of the flow passage F increases toward the discharge port 22, there is a portion where the outer shape of the pump chamber 20 is not arc-shaped (for example, a portion where the outer shape is linear) in the range (first angular range θ) from the downstream end position (first angular position T1) of the flow passage F back to the upstream end position (second angular position T2) of the flow passage F. Therefore, there is a risk that the weld strength may not be sufficient in this area, so by providing a reinforcing rib 46 in this area, it is possible to reinforce the area where the weld strength is insufficient.

[0056] In addition, in this embodiment, by providing the welded portion 40 in a shape that follows the outer shape of the pump chamber 20 instead of the conventional circular welded portion, it is not necessary to provide a flange portion that protrudes outward on the case 2, and the first flange portion 16 provided on the housing 10 side also does not need to protrude significantly outward to form a circular shape. This makes it possible to prevent the case 2 and the housing 10 from becoming large, and also reduces the amount of resin required to manufacture the case 2 and the housing 10.

[0057] In this embodiment, the housing 10 includes a plurality of reinforcing ribs 46 extending parallel to a first direction X perpendicular to the axial direction from a plurality of circumferential positions on the body 14. By providing the reinforcing ribs 46 in such a direction, if the mold for molding the housing 10 is structured to open in the first direction X, the reinforcing ribs 46 can be molded without using a slide mold that slides in a direction intersecting the first direction X (mold opening direction). This makes it possible to avoid complicating the structure of the molding mold in order to provide the reinforcing ribs 46.

[0058] In this embodiment, the second fixing surface 33 includes an additional welding rib 44 arranged on the outer periphery side of the welding rib 42, and the first fixing surface 19 includes an additional welding recess 43 arranged on the outer periphery side of the welding recess 41. The multiple reinforcing ribs 46 include reinforcing ribs 461, 462, and 463 arranged at the angular positions where the additional welding rib 44 and the additional welding recess 43 are provided. Therefore, the location where the reinforcing rib 46 is arranged can be further reinforced by the additional welding portion, so that a high reinforcing effect can be obtained. In this embodiment, the reinforcing rib 46 and the additional welding portion are provided so that the joint strength between the case 2 and the first flange portion 16 is uniform at all angular positions. In addition, the case 2 and the housing 10 only need to be extended far outward at the locations where the additional welding rib 44 and the additional welding recess 43 are provided. Therefore, the size of the case 2 and the housing 10 can be suppressed.

[0059] In this embodiment, among the multiple reinforcing ribs 46, the reinforcing ribs 46 arranged on the protruding portions 17 and 18 Each of the reinforcing ribs 461, 462, 463 extends from a position overlapping the welding rib 42 as viewed from the axial direction to a position overlapping the additional welding rib 44 as viewed from the axial direction. In this way, by arranging the reinforcing ribs 461, 462, 463 so as to straddle both the inner welding portion 40 and the outer additional welding portion, the reinforcing effect can be enhanced. In addition, since the additional welding rib 44 is provided on the protruding portions 17, 18 that protrude largely toward the outer periphery, by extending the reinforcing ribs 461, 462, 463 to the additional welding rib 44, the protruding portions 17, 18 that protrude largely can be reinforced. Therefore, it is possible to suppress a decrease in welding strength caused by the additional welding rib 44 being unable to sufficiently contact the additional welding recess 43 due to deformation of the protruding portions 17, 18.

[0060] In this embodiment, the case 2 includes an attachment portion 24 disposed on the outer periphery of the pump chamber forming portion 23. The pump chamber forming portion 23 includes a side wall portion 26 surrounding the outer periphery of the pump chamber 20, and protruding portions 31, 32 protruding from the side wall portion 26 toward the outer periphery, and the attachment portion 24 is disposed on the outer periphery of the protruding portions 31, 32. The second fixing surface 33 includes a first region 34 formed of an end face of the other axial side L2 of the side wall portion 26, and second regions 35, 36 formed of end faces of the other axial side L2 of the protruding portions 31, 32, and a welding rib 42 or a welding recess 41 is provided in the first region 34, and an additional welding rib 44 or an additional welding recess 43 is provided in the second regions 35, 36. Therefore, when an attachment portion 24 for fixing the pump device 1 to a mating member is provided on the case 2, the attachment portion 24 can be reinforced by providing the protrusions 31 and 32, and space can be secured for arranging additional welding ribs 44 for reinforcing purposes on the end faces of the protrusions 31 and 32.

[0061] In this embodiment, the reinforcing rib 46 overlaps with the linearly extending portion of the welding rib 42 when viewed from the axial direction. The linearly extending portion of the welding rib 42 is more likely to collapse than the arcuately extending portion, making it difficult to ensure sufficient welding strength. Therefore, by providing the reinforcing rib 46 at this portion, it is possible to reinforce the portion where the welding strength is insufficient.

[0062] (Other embodiments) (1) In the above embodiment, the second fixing surface 33 is provided with the welding rib 42, and the first fixing surface 19 is provided with the welding recess 41, but the concave and convex shapes can be reversed. That is, one of the first fixing surface 19 and the second fixing surface 33 can be provided with the welding rib 42, the other of the first fixing surface 19 and the second fixing surface 33 can be provided with the welding recess 41 to which the welding rib 42 is welded, and the reinforcing rib 46 can be configured to overlap the welding rib 42 and the welding recess 41 when viewed from the axial direction. Similarly, the concave and convex shapes can be reversed for the additional welding recess 43 and the additional welding rib 44. That is, one of the first fixing surface 19 and the second fixing surface 33 can be configured with the additional welding rib 44 arranged on the outer periphery side of the welding rib 42, and the other of the first fixing surface 19 and the second fixing surface 33 can be configured with the additional welding recess 43 arranged on the outer periphery side of the welding recess 41.

[0063] (2) In the above embodiment, the additional welded portions (additional weld recess 43, additional welded rib 44) are provided in two locations, but the location and number of the additional welded portions are not limited to the location and number of the present invention. For example, the additional welded portion may be provided in only one location on the outer periphery of discharge port 22. Alternatively, the stress applied to each part of welded portion 40 can be analyzed, and additional welded portions can be provided as appropriate in locations where reinforcement is required. Note that it is also possible to provide only welded portion 40 without providing any additional welded portions.

[0064] (3) In the above embodiment, the reinforcing rib 46 overlaps with the welding rib 42 and the additional welding rib 44 , but the reinforcing rib 46 does not have to overlap with the additional welding rib 44 .

[0065] (4) In the above embodiment, the shape of the pump chamber 20 is such that the width of the flow passage F extending in the circumferential direction around the outer periphery of the impeller 4 increases toward one circumferential side R1, but the shape of the pump chamber 20 is not limited to this. For example, the outer shape of the pump chamber 20 may be circular when viewed in the axial direction. [Explanation of symbols]

[0066] REFERENCE SIGNS LIST 1...pump device, 2...case, 3...motor, 4...impeller, 5...stator, 6...rotor, 7...support shaft, 8...board, 9...cover, 10...housing, 11...first partition wall portion, 12...second partition wall portion, 13...bottom wall, 14...body portion, 15...connector housing, 16...first flange portion, 17, 18...protruding portion, 19...first fixing surface, 20...pump chamber, 21...suction port, 22...discharge port, 23...pump chamber forming portion, 24...mounting portion, 25...upper wall portion, 26...side wall portion, 27...first recess, 28...second recess, 29...projection portion, 31, 32...protruding portion, 33...second fixing surface, 34...first region, 35, 36...second region, 40...welding portion, 41...welding recess, 42...welding rib, 43...additional welding recess, 44...additional welding rib, 46, 461, 462, 4 63...reinforcing rib, 50...coil, 51...stator core, 52, 53...insulator, 55...winding terminal, 60...rotor member, 61...magnet, 62...cylindrical portion, 63...flange portion, 64...wing portion, 65...plate, 66...circular hole, 70...radial bearing, 71...shaft hole, 72...support portion, 73...cylindrical portion, 74...thrust bearing, 90...opening, 91...heat dissipation Member, 420...curved portion, 421...first straight portion, 422...second straight portion, 441...first portion, 442...second portion, F...flow path, L...rotation axis, L1...one side in the axial direction, L2...other side in the axial direction, R1...one side in the circumferential direction, R2...other side in the circumferential direction, S...gap, T1...first angular position, T2...second angular position, X...first direction, Y...second direction, θ...first angular range

Claims

1. a rotor and a stator surrounding the outer periphery of the rotor; a housing that seals the stator; a case including a pump chamber forming portion that is fitted over the housing from one side in an axial direction along a rotation axis of the rotor to form a pump chamber between the housing and the pump chamber forming portion; an impeller disposed in the pump chamber and rotating integrally with the rotor; the housing includes a first partition portion covering one side of the stator in the axial direction, a body portion covering an outer periphery of the stator, a first flange portion protruding from the body portion toward the outer periphery, and a reinforcing rib connecting an outer periphery of the body portion and the first flange portion, The first flange portion includes a first fixing surface facing one side in the axial direction, The pump chamber forming portion includes a second fixing surface facing the first fixing surface, One of the first fixing surface and the second fixing surface includes a welding rib; the other of the first fixing surface and the second fixing surface includes a welding recess to which the welding rib is welded; The pump device according to claim 1, wherein the reinforcing rib overlaps with the welding rib and the welding recess when viewed from the axial direction.

2. the pump chamber forming portion includes an intake port provided at a radial center of the pump chamber and an outlet port provided at an outer circumferential portion of the pump chamber, the intake port and the outlet port opening to one side in the axial direction, The pump device according to claim 1 , wherein the reinforcing rib is disposed at an angular position where the discharge port is provided.

3. a shape of the pump chamber as viewed from the axial direction such that a width of a flow path extending in a circumferential direction around an outer periphery of the impeller increases toward one side in the circumferential direction, The welding rib extends along an outer shape of the pump chamber as viewed from the axial direction, When an angular position where the width of the flow path is the largest is defined as a first angular position, and an angular position where the width of the flow path is the smallest is defined as a second angular position, The discharge port is provided at the first angular position, The pump device according to claim 2 , wherein the reinforcing rib is provided within a first angular range up to the second angular position on one side in the circumferential direction of the first angular position.

4. The pump device according to claim 1 , wherein the housing includes a plurality of reinforcing ribs extending in parallel to a first direction perpendicular to the axial direction from a plurality of circumferential positions on the body portion.

5. The one of the first fixing surface and the second fixing surface includes an additional welding rib arranged on an outer circumferential side of the welding rib, the other of the first fixing surface and the second fixing surface includes an additional welding recess disposed on an outer circumferential side of the welding recess, The pump device according to claim 1 , wherein the reinforcing rib is disposed at an angular position where the additional welding rib and the additional welding recess are provided.

6. 6. The pump device according to claim 5, wherein the reinforcing rib extends from a position overlapping the welding rib when viewed in the axial direction to a position overlapping the additional welding rib when viewed in the axial direction.

7. the case includes an attachment portion disposed on an outer circumferential side of the pump chamber forming portion, The pump chamber forming portion includes a side wall portion surrounding the outer periphery of the pump chamber, and a The mounting portion is disposed on the outer circumferential side of the protruding portion. the second fixing surface includes a first region formed by an end face on the other side in the axial direction of the side wall portion, and a second region formed by an end face on the other side in the axial direction of the protruding portion, The welding rib or the welding recess is provided in the first region, The pump device according to claim 5, wherein the additional welding rib or the additional welding recess is provided in the second region.

8. 2. The pump device according to claim 1, wherein the reinforcing rib overlaps with a linearly extending portion of the welding rib when viewed from the axial direction.

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