Pump device

Abstract

The invention provides a pump device, which suppresses the enlargement of a housing and a housing when the housing is welded to the housing of a motor to form an involute-shaped pump chamber. A pump device (1) has a pump chamber (20) formed between a housing (10) of a motor (3) that rotates an impeller (4) and a housing (2). The pump chamber (20) has a shape in which the width of a flow path (F) extending in the circumferential direction on the outer periphery of the impeller (4) increases toward one side (R1) in the circumferential direction. The housing (10) is provided with a first flange portion (16) protruding to the outer peripheral side from a main body portion (14) covering the outer periphery of the stator (5). The housing (2) has a second fixing surface (33) facing the first fixing surface (19) of the first flange portion (16). The second fixing surface (33) is provided with a welding rib (42) extending along the outer shape of the pump chamber (20) as viewed from the axial direction, and the first fixing surface (19) is provided with a welding recess (41) to which the welding rib (42) is welded.

Description

Technical Field

[0001] The present invention relates to a pump device for sucking a fluid into a pump chamber and discharging the fluid by rotating an impeller. Background Art

[0002] Patent Documents 1 and 2 describe pump devices for circulating cooling water. In the pump device of Patent Document 1, a pump chamber is formed between a housing (resin sealing component) covering an annular stator and a casing fixed to an end of the housing. The impeller rotates integrally with a rotor arranged on the inner periphery of the stator. The casing has a suction pipe connected to the radial center of the pump chamber and a discharge pipe connected to the outer periphery of the pump chamber.

[0003] In Patent Document 1, a pump chamber is formed by bringing an annular flange portion provided at the end of a housing into contact with an annular flange portion provided at the 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 circumference of the flange portion. Therefore, the variation in weld strength is small.

[0004] In a pump device that rotates an impeller in the center of a pump chamber, provides a fluid suction port in the center of the pump chamber, and provides a discharge port for discharging fluid on the periphery of the pump chamber, the shape of the pump chamber is sometimes a shape in which the width of the flow path surrounding the impeller widens 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. The pump device of patent document 2 fastens a housing (pump base portion) and a casing (pump mounting portion) on the periphery of the pump chamber by bolts. Prior art literature Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-020102 Patent Document 2: Japanese Patent Application Publication No. 2010-089776 Summary of the invention

[0006] When the pump chamber is formed into a shape in which the width of the flow path widens toward one side in the circumferential direction and the housing and the shell are welded to form the pump chamber as in Patent Document 1, a circular flange is provided to reduce the variation in weld strength and a welded portion is provided along the outer circumference thereof. The outer shape of the flange observed from the axial direction becomes larger, and the housing and the shell are enlarged. As a result, the amount of resin required to manufacture the housing and the shell increases.

[0007] In view of the above problems, an object of the present invention is to suppress an increase in the size of the case and the housing when a pump chamber having a non-circular shape as viewed in the axial direction is formed by welding the case to the housing of a motor.

[0008] In order to solve the above-mentioned problems, the pump device of the present invention comprises: a motor having a rotor and a stator surrounding the outer circumference of the rotor; a casing that seals the stator; a housing that covers the housing from one side in the axial direction along the axis of rotation of the rotor and comprises a pump chamber forming portion that forms a pump chamber between the housing and the impeller; and an impeller that is arranged in the pump chamber and rotates integrally with the rotor, the shape of the pump chamber observed from the axial direction is a shape in which the width of a flow path extending in the circumferential direction on the outer circumference of the impeller increases toward one side in the circumferential direction, and the housing comprises : A first partition wall covering one side of the stator in the axial direction; a main body covering the outer periphery of the stator; and a first flange protruding from the main body toward the outer periphery, the first flange having a first fixing surface facing one side in the axial direction, the pump chamber forming portion having a second fixing surface opposite to the first fixing surface, one of the first fixing surface and the second fixing surface having a welding rib extending along the outer shape of the pump chamber observed from the axial direction, and the other of the first fixing surface and the second fixing surface having a welding recess to which the welding rib is welded.

[0009] According to the present invention, the outer shell and the housing are welded to form a pump chamber between the outer shell and the housing, and the shape of the pump chamber is such that the width of the flow path extending in the circumferential direction on the outer periphery of the impeller increases as it approaches one side in the circumferential direction. In this way, when forming a non-circular pump chamber, by forming the welding ribs for welding the outer shell and the housing into a shape extending along the outer shape of the pump chamber observed from the axial direction, it is not necessary to provide a flange portion that extends largely toward the outer peripheral side on the housing and the housing. Therefore, it is possible to suppress the enlargement of the housing and the housing, and it is possible to suppress the amount of resin required to manufacture the housing and the housing.

[0010] In the present invention, it is preferred that one of the first fixing surface and the second fixing surface has an additional welding rib disposed on the outer peripheral side of the welding rib, and the other of the first fixing surface and the second fixing surface has an additional welding recess for welding the additional welding rib. In this way, the portion of the welding portion extending along the outer shape of the pump chamber where the welding strength is insufficient can be reinforced. Therefore, it is possible to suppress the reduction in durability caused by the deviation in the welding strength of the welding portion or the stress applied to the welding portion. In addition, in this case, the housing and the outer shell only need to extend the portion where the additional welding portion is provided toward the outer peripheral side. Therefore, it is possible to suppress the enlargement of the housing and the outer shell.

[0011] In the present invention, it is preferred that the additional welding rib is arranged on the outer peripheral side of the portion where the welding rib extends in a straight line. In the portion where the welding rib extends in a straight line, the welding rib is more inclined than the portion where the welding rib extends in an arc shape, so the welding strength cannot be ensured. Therefore, by providing the additional welding rib and the additional welding recess to strengthen the portion, the portion with insufficient welding strength can be strengthened.

[0012] In the present invention, it is preferred that when the angle position at which the width of the flow path extending in the circumferential direction on the outer periphery of the impeller is the largest is set as the first angle position, and the angle position at which the width of the flow path is the smallest is set as the second angle position, the pump chamber forming portion includes: a suction port arranged at the radial center of the pump chamber; and a discharge port arranged at the first angle position, the welding rib includes a first reinforced portion arranged at a first angle range to the second angle position on one side of the circumferential direction of the first angle position, and the additional welding rib and the additional welding recess are arranged on the outer peripheral side of the first reinforced portion. In this way, the shape of the pump chamber of the present invention has a portion where the outer shape of the pump chamber is not arc-shaped within the range (first angle range) from the position of the downstream end of the flow path (first angle position) to the position (second angle position) returning to the upstream end. Therefore, there is a possibility that the welding strength cannot be ensured at this portion, so by providing an additional welding portion at this portion for reinforcement, the portion with insufficient welding strength can be strengthened.

[0013] In the present invention, the suction port and the discharge port are opened on one side of the axial direction. In this case, near the discharge port, the direction of the fluid flowing in the circumferential direction changes to a direction toward one side of the axial direction. Therefore, the direction and magnitude of the fluid pressure applied to the inner circumferential surface of the pump chamber are different from those of other parts, and it may be impossible to ensure the necessary welding strength. Therefore, by providing additional welding ribs and additional welding recesses at this part, the part with insufficient welding strength can be strengthened.

[0014] In the present invention, it is preferred that the additional welding ribs and the additional welding recesses are arranged on the outer peripheral side of the first reinforced portion and the outer peripheral side of the second reinforced portion on the radially opposite side to the first reinforced portion. The inventors have confirmed through analysis that when the portion with the lowest welding strength (the first reinforced portion) is reinforced, the portion on the radially opposite side of the reinforced portion (the second reinforced portion) becomes the portion with the second lowest welding strength. Therefore, by providing the additional welding ribs and the additional welding recesses in this portion, the portion with insufficient welding strength can be reinforced.

[0015] In the present invention, it is preferred that the additional welding rib has a first portion extending in a direction intersecting the welding rib on the outer peripheral side of the welding rib, and a gap is provided between the end of the inner peripheral side of the first portion and the welding rib. In this way, the welding rib can be prevented from being easily overturned by the first portion. Therefore, the welding portion can be effectively strengthened. In addition, by providing a gap between the first portion and the welding rib, a space for accommodating welding burrs can be ensured.

[0016] In the present invention, it is preferred that the additional welding rib comprises: the first portion disposed at two locations separated from each other in the circumferential direction; and the second portion connecting the ends of the first portion on the outer circumferential side at the two locations. In this way, the welding rib can be reinforced at two locations, and the additional welding rib itself is not easy to fall over. Therefore, the reinforcement effect can be improved.

[0017] In the present invention, it is preferred that the housing has a mounting portion arranged on the outer peripheral side of the pump chamber forming portion, the pump chamber forming portion has: a side wall portion surrounding the outer periphery of the pump chamber; and a protrusion protruding from the side wall portion to the outer peripheral side, the mounting portion is arranged on the outer peripheral side of the protrusion, and the second fixing surface includes: a first area formed by the end surface on the other side of the axial direction of the side wall portion; and a second area formed by the end surface on the other side of the axial direction of the protrusion, the welding rib or the welding recess is arranged in the first area, and the additional welding rib or the additional welding recess is arranged in the second area. In this way, when the mounting portion for fixing the pump device to the other part is arranged in the housing, the space for arranging the additional welding rib or the additional welding recess for reinforcement can be ensured by using the structure for connecting the mounting portion and the pump chamber forming portion (the protrusion protruding from the side wall portion of the pump chamber forming portion).

[0018] In the present invention, it is preferred that the housing has a reinforcing rib connecting the outer peripheral surface of the main body and the first flange, and the reinforcing rib overlaps the welding rib when viewed from the axial direction. In this way, the reinforcing rib can be used to reinforce the portion where the welding strength is insufficient. For example, the reinforcing rib can be used to suppress deformation of the first flange, and the reduction in welding strength caused by insufficient contact between the welding rib and the welding recess can be suppressed.

[0019] In the present invention, preferably, when viewed from the axial direction, the reinforcing rib extends from a position overlapping with the welding rib to a position overlapping with the additional welding rib. In this way, by providing the reinforcing rib in a manner spanning two welding portions, the reinforcing effect can be improved.

[0020] According to the present invention, the outer shell and the housing are welded to form a pump chamber between the outer shell and the housing, and the shape of the pump chamber is such that the width of the flow path extending in the circumferential direction on the outer periphery of the impeller increases as it approaches one side in the circumferential direction. In this way, when forming a non-circular pump chamber, by forming the welding ribs for welding the outer shell and the housing into a shape extending along the outer shape of the pump chamber observed from the axial direction, it is not necessary to provide a flange portion that extends largely toward the outer peripheral side on the housing and the housing. Therefore, it is possible to suppress the enlargement of the housing and the housing, and it is possible to suppress the amount of resin required to manufacture the housing and the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a cross-sectional view of a pump device to which the present invention is applied. Figure 2 This is a top view of the housing as viewed from the other side in the axial direction. Figure 3 This is a perspective view of the housing as viewed from the other side in the axial direction. Figure 4 This is an exploded perspective view of the rotor and housing viewed from one side in the axial direction. Figure 5 This is a perspective view of the pump device as viewed from the other side in the axial direction. Figure 6 It is an explanatory diagram showing the arrangement of welding ribs, additional welding ribs, and reinforcing ribs. DETAILED DESCRIPTION

[0022] Hereinafter, the pump device 1 according to the embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, the axial direction refers to the direction in which the rotation axis L of the motor 3 extends (the direction 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 rotation direction centered on the rotation axis L. In addition, the direction in which the rotation axis L extends is set as the axial direction, one side of the axial direction is set as L1, and the other side of the axial direction is set as L2. In addition, one side of the circumferential direction is set as R1, and the other side of the circumferential direction is set as R2.

[0023] (Overall structure) Figure 1 2 is a cross-sectional view of the pump device 1 to which the present invention is applied, and is a cross-sectional view obtained by cutting the pump device 1 along a plane including the rotation axis L. Figure 1 As shown, the pump device 1 includes: a housing 2, which is provided with a suction port 21 and a discharge port 22 which are open to one side L1 in the axial direction; a motor 3, which is arranged on the other side L2 in the axial direction relative to the housing 2; and an impeller 4, which is arranged in a pump chamber 20, and the pump chamber 20 is arranged between the housing 10 of the motor 3 and the housing 2.

[0024] The impeller 4 is driven by the motor 3 to rotate around the rotation axis L. In the pump device 1 of the present embodiment, the fluid flowing in the pump chamber 20 is a liquid. The fluid supplied to the pump chamber 20 from the suction port 21 provided at the radial center of the housing 2 moves in the circumferential direction in the pump chamber 20 as the impeller 4 rotates, and is discharged from the discharge port 22 provided at the outer peripheral portion of the pump chamber 20. The suction port 21 and the discharge port 22 are open at the end surface of one side L1 of the housing 2 in the axial direction.

[0025] The motor 3 includes a ring-shaped stator 5, a rotor 6 disposed inside the stator 5, a support shaft 7 that supports the rotor 6 so as to be rotatable, a substrate 8 disposed on the other side L2 of the axial direction 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 sides in the radial direction and both sides in the axial direction. The housing 10 is made of polyphenylene sulfide (PPS). The stator 5 is integrated with the housing 10 by insert molding.

[0026] The stator 5 includes: an annular stator core 51; an insulator 52 overlapping the stator core 51 from one side L1 in the axial direction; an insulator 53 overlapping the stator core 51 from the other side L2 in the axial direction; 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. Therefore, the plurality of coils 50 are composed of a U-phase coil, a V-phase coil, and a W-phase coil.

[0027] The housing 10 is a partition wall member having a first partition wall 11 covering one side L1 of the axial direction of the stator 5, a second partition wall 12 covering the inner peripheral side of the stator 5, and a bottom wall 13 provided at an end portion of the second partition wall 12 at the other side L2 of the axial direction. The housing 10 also includes: a cylindrical main body 14 covering the stator 5 from the radially outer side; a cylindrical connector housing 15 extending radially outward from the main body 14 at the radially outer side of the stator 5; and a first flange 16 extending radially outward from an end portion of the main body 14 at the one side L1 of the axial direction. The first flange 16 is connected to the connector housing 15.

[0028] The cover 9 is fixed to the end of the other side L2 of the main 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 by a metal heat dissipation component 91 from one side L1 in the axial direction. A metal winding terminal 55 is connected to the substrate 8 arranged between the cover 9 and the bottom wall 13 of the housing 10, and the winding terminal 55 passes through the bottom wall 13 of the housing 10 from the stator 5 and protrudes to the other side L2 in the axial direction. 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 substrate 8 is supplied to each coil 50 via the winding terminal 55. As a result, the rotor 6 and the impeller 4 rotate as a whole, the interior of the pump chamber 20 becomes a negative pressure, and the fluid is sucked into the pump chamber 20 from the suction port 21 and discharged from the discharge port 22.

[0029] The rotor 6 includes a resin rotor member 60 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 disc-shaped flange portion 63 extending from the end of one side L1 of the axial direction of the cylindrical portion 62 to the outer peripheral side. The magnet 61 is fixed to the outer peripheral surface of the cylindrical portion 62. The magnet 61 faces the stator 5 on the radial inner side. The magnet 61 is composed of, for example, a neodymium bond magnet.

[0030] A radial bearing 70 is held inside the cylindrical portion 62. The rotor 6 is rotatably supported on the support shaft 7 by the radial bearing 70. The end portion on the other side L2 of the support shaft 7 in the axial direction is held in a shaft hole 71 formed in the bottom wall 13 of the housing 10. The housing 2 has three support portions 72 extending from the inner circumferential surface of the suction port 21 toward the motor 3, and a cylinder portion 73 is provided at the front end of the support portion 72, and the end portion on the one side L1 of the support shaft 7 in the axial direction is embedded in the inner side of the cylinder portion 73. A thrust bearing 74 is arranged between the cylinder portion 73 and the radial bearing 70, and the thrust bearing 74 is mounted on the end portion on the one side L1 of the support shaft 7 in the axial direction.

[0031] A plurality of blades 64 protrude from the flange 63 of the rotor member 60 toward one side L1 in the axial direction, and a resin plate 65 is fixed to the front end of the blade 64 from one side L1 in the axial direction. The plurality of blades 64 extend radially outward while being curved into an arc shape, and are arranged at equal angle intervals. The flange 63, the blades 64, and the plate 65 constitute the impeller 4. The three support portions 72 provided on the housing 2 are arranged inside the circular hole 66 provided in the center of the plate 65, and are connected to the cylinder 73 arranged inside the cylindrical portion 62 of the rotor member 60.

[0032] (case) Figure 2 It is a plan view of the housing 2 as viewed from the other side L2 in the axial direction. Figure 3 This is a three-dimensional view of the housing 2 viewed from the other side L2 in the axial direction. Figure 1As shown, the housing 2 covers the outer shell 10 from one side L1 in the axial direction. Figure 1 , Figure 2 , Figure 3 As shown, the housing 2 includes: a pump chamber forming portion 23 that forms a pump chamber 20 between the housing 10; and a mounting portion 24 with holes disposed on the outer peripheral side of the pump chamber forming portion 23. The pump device 1 is fixed to a counterpart component (not shown) via three mounting portions 24 provided on the housing 2. At this time, the suction port 21 and the discharge port 22 provided on the housing 2 are positioned at positions that can be connected to a flow path such as a hole or a pipe provided on the counterpart component.

[0033] like Figure 1 , Figure 2 , Figure 3 As shown, the pump chamber forming portion 23 includes: an upper wall portion 25, the suction port 21 and the discharge port 22 penetrate the upper wall portion 25 in the axial direction; and a side wall portion 26, which protrudes from the upper wall portion 25 to the other side L2 in the axial direction and surrounds the outer periphery of the pump chamber 20. The upper wall portion 25 is provided with: a circular first recessed portion 27 recessed to one side L1 in the axial direction with the rotation axis L as the center; and a second recessed portion 28 recessed to one side L1 in the axial direction at the outer periphery of the first recessed portion 27. The cross-sectional shape of the second recessed portion 28 when cut in the radial direction is approximately semicircular, and the side wall portion 26 extends along the outer peripheral shape of the second recessed portion 28.

[0034] like Figure 1 As shown, in the pump chamber 20, the upper portion of the impeller 4 is disposed in the first recess 27, and the flow path F surrounded by the second recess 28 and the side wall 26 extends in the circumferential direction on the outer periphery of the impeller 4. Figure 2 , Figure 3 As shown, the second recess 28 is a shape whose radial width increases toward one circumferential side R1. Therefore, the pump chamber 20 is formed in a shape whose width of the flow path F extending in the circumferential direction at the outer periphery of the impeller 4 increases toward one circumferential side R1. As an example of such a shape, there is an involute shape.

[0035] like Figure 2 As shown, the end of one side R1 of the second recess 28 in the circumferential direction is located at the first angular position T1, and the end of the other side R2 in the circumferential direction is located at the second angular position T2. ​​The flow path F extending in the circumferential direction on the inner periphery of the pump chamber 20 extends from the second angular position T2 to the one side R1 in the circumferential direction to the first angular position T1. The second angular position T2 is the angular position where the width of the flow path F is the smallest, and the first angular position T1 is the angular position where the width of the flow path F is the largest.

[0036] like Figure 2 , Figure 3As shown, the discharge port 22 opens to the bottom of the second recessed portion 28 at the first angular position T1. In the range from one side R1 in the circumferential direction 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 is provided that protrudes from the inner circumferential surface of the side wall portion 26 and the bottom surface of the second recessed portion 28 toward the inner side of the pump chamber 20. Therefore, the fluid flowing toward the one side R1 in the circumferential direction in the pump chamber 20 collides with the convex portion 29 at the first angular position T1 and flows toward the discharge port 22.

[0037] like Figure 2 , Figure 3 As shown, the pump chamber forming portion 23 has two protrusions 31 and 32 protruding from the side wall portion 26 to the outer peripheral side. The protrusion 31 is provided within the first angle range θ and is arranged on the outer peripheral side of the discharge port 22 and the convex portion 29. The protrusion 32 is provided at a position on the opposite side in the radial direction relative to the protrusion 31. Two of the three mounting portions 24 provided on the housing 2 are arranged on the outer peripheral side of the protrusions 31 and 32. Therefore, the mounting portion 24 is reinforced by the protrusions 31 and 32.

[0038] (Welding section) Figure 4 This is an exploded perspective view of the rotor 6 and the housing 10 as viewed from one side L1 in the axial direction. Figure 4 As shown, the first flange portion 16 is provided on the entire circumference of the main body portion 14. The outer shape of the first flange portion 16 is substantially consistent with the outer shape of the pump chamber forming portion 23 observed from the axial direction. The first flange portion 16 has protrusions 17 and 18 that overlap with two protrusions 31 and 32 provided on the pump chamber forming portion 23 when viewed from the axial direction.

[0039] like Figure 1 , Figure 4 As shown in FIG. 1 , the first flange portion 16 includes a first fixing surface 19 facing one side L1 in the axial direction. Figure 1 , Figure 3 As shown, the pump chamber forming portion 23 includes the end surface of the other side L2 of the side wall portion 26 and the protrusions 31 and 32 in the axial direction, that is, the second fixing surface 33. The first fixing surface 19 and the second fixing surface 33 are opposite to each other in the axial direction. The welding rib 42 provided on the second fixing surface 33 is welded to the welding recess 41 provided on the first fixing surface 19 by vibration welding, thereby joining the housing 2 and the shell 10. The welding portion 40 (refer to Figure 1 ) surrounds the pump chamber 20 over the entire circumference.

[0040] When the housing 2 and the casing 10 are joined by vibration welding, for example, the pump chamber forming portion 23 is overlapped with the first flange portion 16 from one side L1 in the axial direction, and the first flange portion 16 is pressurized from the other side L2 in the axial direction. Since the axial height of the welding rib 42 is greater than the depth of the welding recess 41, the front end of the welding rib 42 inserted into the welding recess 41 is pressed 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.

[0041] In addition, an additional welding recess 43 is provided on the outer peripheral side of the welding recess 41 on the first fixing surface 19 on the first flange portion 16, and an additional welding rib 44 is provided on the outer peripheral side of the welding rib 42 on the second fixing surface 33 on the housing 2. The additional welding recess 43 and the additional welding rib 44 are provided at two locations on the radially opposite sides. When the housing 2 is joined to the housing 10 by vibration welding, additional welding portions where the additional welding recess 43 and the additional welding rib 44 are welded are formed at two locations on the radially opposite sides on the outer peripheral side of the welding portion 40. Therefore, the welding portion 40 is reinforced at two locations.

[0042] like Figure 4 As shown, the welding recess 41 extends on the first fixing surface 19 in a shape along the outer shape of the pump chamber 20 observed from the axial direction. One of the two additional welding recesses 43 extends along the outer periphery of the protrusion 17, and its two ends are connected to the welding recess 41. The other additional welding recess 43 is provided in the protrusion 18. In the protrusion 18, the additional welding recess 43 extends to the entire protrusion 18 to form a whole with the welding recess 41.

[0043] like Figure 2 , Figure 3 As shown, the welding rib 42 extends on the second fixing surface 33 in a shape along the outer shape of the pump chamber 20 observed from the axial direction. More specifically, the welding rib 42 includes: a bent portion 420 that bends from the second angular position T2 to the one side R1 in the circumferential direction and extends to the first angular position T1; a first straight portion 421 that bends to the inner circumferential side at the first angular position T1 and extends in a straight line; and a second straight portion 422 that bends from the one side R1 in the circumferential direction of the first straight portion 421 in a direction that forms an obtuse angle with the first straight portion 421 and extends in a straight line to the second angular position T2.

[0044] Thus, in the present embodiment, by providing the welding portion 40 along the outer shape of the pump chamber 20, a portion of the welding portion 40 does not become curved in the first angle range θ, but extends in a straight line. When subjected to fluid pressure, the first straight portion 421 and the second straight portion 422 of the welding rib 42 are more easily inclined than the curved portion 420. Therefore, the welding strength of the welding portion 40 where the first straight portion 421 and the second straight portion 422 are welded to the welding recess 41 is the lowest. One of the two additional welding portions uses the first straight portion 421 and the second straight portion 422 as the first reinforced portion and is arranged on the outer peripheral side of the first reinforced portion, thereby reinforcing the portion of the welding portion 40 where the welding strength is the lowest.

[0045] Here, it was confirmed through analysis that when the additional welded portion is provided on the outer peripheral side of the first straight portion 421 and the second straight portion 422, the portion with the lowest weld strength is the portion on the radially opposite side to the first straight portion 421 and the second straight portion 422. Therefore, the portion on the radially opposite side to the first straight portion 421 and the second straight portion 422 is used as the second reinforced portion, and the additional welded portion (the additional welded recessed portion 43 and the additional welded rib 44) is also arranged on the outer peripheral side of the second reinforced portion.

[0046] like Figure 2 , Figure 3 As shown, the second fixing surface 33 includes a first region 34, which is an end surface on the other side L2 of the axial direction of the side wall portion 26 and surrounds the outer periphery of the pump chamber 20 over the entire circumference, and a welding rib 42 is arranged in the first region 34. In addition, the second fixing surface 33 includes two second regions 35 and 36, which are end surfaces on the other side L2 of the axial direction of the protrusions 31 and 32 and are provided on the outer peripheral side of the first region 34. The second region 35 expands toward the outer peripheral side of the first straight portion 421 and the second straight portion 422. The second region 36 expands toward the outer peripheral side of the curved portion 420 at a position on the opposite side in the radial direction relative to the first straight portion 421 and the second straight portion 422. Additional welding ribs 44 are provided in the second regions 35 and 36.

[0047] The additional welding ribs 44 extend continuously along the outer periphery of the second regions 35 and 36. Each additional welding rib 44 has a shape in which it extends linearly toward the outer periphery of the welding rib 42, bends in the opposite direction, and extends linearly toward the welding rib 42. In other words, the two additional welding ribs 44 each include a first portion 441, the first portion 422 extends linearly in a direction intersecting the welding rib 42 on the outer periphery of the welding rib 42, and the first portion 422 is provided at two locations separated in the circumferential direction. Furthermore, the ends of the outer periphery of the two first portions 441 are connected by the second portion 442 extending in the circumferential direction while bending.

[0048] 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 circumference 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 for accommodating welding burrs generated when the additional welding rib 44 is welded is ensured.

[0049] (Reinforcement Ribs) Figure 5 The pump device 1 is a perspective view 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. Figure 4 , Figure 5 As shown, the housing 10 has reinforcing ribs 46 connecting the main body 14 and the first flange 16 at multiple locations. The reinforcing ribs 46 protrude from the outer peripheral surface of the main body 14 in the first direction X, and are connected to the surface of the first flange 16 on the other side L2 in the axial direction. Each reinforcing rib 46 is a shape in which the radial length increases toward the one side L1 in the axial direction, and extends to the outer peripheral edge of the first flange 16. The plurality of reinforcing ribs 46 are arranged along the second direction Y and extend parallel to the first direction X. In the present embodiment, the plurality of reinforcing ribs 46 protrude in parallel from the outer peripheral surface of the main body 14 toward one side in the first direction X (the side where the protrusion 31 and the protrusion 17 are provided) and the other side in the first direction X (the side where the protrusion 32 and the protrusion 18 are provided).

[0050] Figure 6 1 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 side L2 in the axial direction. The plurality of reinforcing ribs 46 overlap with the welding rib 42 when viewed from the axial direction. Among the plurality of reinforcing ribs 46, one reinforcing rib 461 connected to the protruding portion 17 of the first flange portion 16 and two reinforcing ribs 462 and 463 connected to the protruding portion 18 of the first flange portion 16 overlap with both the welding rib 42 and the additional welding rib 44 when viewed from the axial direction.

[0051] The reinforcing rib 461 connected to the protruding portion 17 of the first flange portion 16 is arranged within the first angular range θ and is provided at a position overlapping the discharge port 22 when viewed from the axial direction. The reinforcing rib 461 extends from a position overlapping the second straight portion 422 of the welding rib 42 to a position overlapping the additional welding rib 44 extending along the outer peripheral edge of the protruding portion 17.

[0052] The two reinforcing ribs 462 and 463 connected to the protruding portion 18 of the first flange portion 16 are arranged at positions on the opposite sides in the radial direction with respect to the first angular range θ. The reinforcing ribs 462 and 463 extend from positions overlapping with the second reinforced portion of the welding rib 42 (i.e., positions on the opposite sides in the radial direction with respect to the first straight portion 421 and the second straight portion 422) in the axial direction to positions overlapping with the additional welding rib 44 extending along the outer peripheral edge of the protruding portion 18.

[0053] (Main effects of this embodiment) As described above, the pump device 1 of the present embodiment includes: the rotor 6 and the stator 5 surrounding the outer periphery of the rotor 6; the housing 10 sealing the stator 5; the housing 2 covering the housing 10 from the one side L1 in the axial direction along the rotation axis L of the rotor 6 and including the pump chamber forming portion 23 forming the pump chamber 20 between the housing 10; and the impeller 4 arranged in the pump chamber 20 and rotating integrally with the rotor 6. The shape of the pump chamber 20 viewed from the axial direction is a shape in which the width of the flow path F extending in the circumferential direction on the outer periphery of the impeller 4 increases toward the one side R1 in the circumferential direction. The housing 10 includes: the first partition wall 11 covering the one side L1 in the axial direction of the stator 5; the main body 14 covering the outer periphery of the stator 5; and the first flange 16 protruding from the main body 14 toward the outer peripheral side. The first flange 16 includes the first fixing surface 19 facing the one side L1 in the axial direction, and the pump chamber forming portion 23 includes the second fixing surface 33 facing the first fixing surface 19. The second fixing surface 33 includes a welding rib 42 extending along the outer shape of the pump chamber 20 as viewed in the axial direction, and the first fixing surface 19 includes a welding recess 41 to which the welding rib 42 is welded.

[0054] In the present embodiment, the housing 10 and the casing 2 are welded, and a pump chamber 20 is formed between the housing 10 and the casing 2. The pump chamber 20 is shaped such that the width of the flow path F extending in the circumferential direction on the outer periphery of the impeller 4 increases as it moves toward one side R1 in the circumferential direction. Furthermore, the welding rib 42 for welding the housing 10 and the casing 2 is formed into a shape extending along the outer shape of the pump chamber 20 as viewed from the axial direction. Instead of a circular welding portion as in the past, a welding portion 40 having a shape along the outer shape of the pump chamber 20 is provided. Thus, it is not necessary to provide a flange portion extending toward the outer peripheral side on the casing 2, and it is not necessary to extend the first flange portion 16 provided on the side of the housing 10 to a large extent toward the outer peripheral side in order to form a circular shape. Therefore, it is possible to suppress the enlargement of the casing 2 and the housing 10, and it is possible to suppress the amount of resin required to manufacture the casing 2 and the casing 10.

[0055] In the present embodiment, the second fixing surface 33 provided on the housing 2 is provided with an additional welding rib 44 disposed on the outer peripheral side of the welding rib 42, and the first fixing surface 19 provided on the housing 10 is provided with an additional welding recess 43 to which the additional welding rib 44 is welded. Thus, the portion where the welding strength is insufficient in the welding portion 40 can be locally reinforced, and thus, the decrease in durability of the pump device 1 caused by the insufficient local welding strength can be suppressed. In addition, the housing 2 and the housing 10 only need to extend the portion where the additional welding rib 44 and the additional welding recess 43 are provided to the outer peripheral side to a large extent. Therefore, the enlargement of the housing 2 and the housing 10 can be suppressed.

[0056] In this embodiment, the additional welding rib 44 is arranged on the outer peripheral side of the portion (the first straight portion 421 and the second straight portion 422) where the welding rib 42 extends in a straight line. In the portion where the welding rib 42 extends in a straight line, the welding rib 42 is more inclined than the portion where the welding rib 42 extends in an arc shape, so the welding strength cannot be ensured. Therefore, by providing the additional welding rib 44 and the additional welding recess 43 to reinforce the portion, the portion with insufficient welding strength can be strengthened.

[0057] In the present embodiment, the angular position at which the width of the flow path F extending in the circumferential direction on the outer periphery of the impeller 4 is the largest is set as the first angular position T1, and the angular position at which the width of the flow path F is the smallest is set as the second angular position T2, and the pump chamber forming portion 23 includes a suction port 21 provided at the radial center of the pump chamber 20 and a discharge port 22 provided at the first angular position T1. The portion (first reinforced portion) of the welding rib 42 disposed in the first angular range θ on one side R1 in the circumferential direction of the first angular position T1 is not in an arc shape, but is composed of a first straight portion 421 and a second straight portion 422, wherein the first angular range θ is the range from the first angular position T1 to the second angular position T2. ​​Thus, in the present embodiment, in the range (first angular range θ) from the downstream end position of the flow path F (first angular position T1) to the position (second angular position T2) returning to the upstream end, a portion where the welded portion 40 becomes a straight line is generated, and there is a possibility that the welding strength cannot be ensured. Therefore, by providing the additional welding rib 44 and the additional welding recess 43 on the outer peripheral side of the portion (the first reinforced portion) for reinforcement, the portion with insufficient welding strength can be reinforced.

[0058] In this embodiment, the suction port 21 and the discharge port 22 are open on one side L1 in the axial direction. In this case, near the discharge port 22, the direction of the fluid flowing in the circumferential direction changes to the direction toward the one side L1 in the axial direction. Therefore, the direction and magnitude of the fluid pressure applied to the inner circumferential surface of the pump chamber 20 are different from those of other parts, and it may not be possible to ensure the necessary welding strength. Therefore, by providing additional welding ribs 44 and additional welding recesses 43 to strengthen this part, the part with insufficient welding strength can be strengthened.

[0059] In the present embodiment, the additional welding ribs 44 and the additional welding recesses 43 are arranged on the outer peripheral side of the first straight portion 421 and the second straight portion 422 (the first reinforced portion) and on the outer peripheral side of the portion (the second reinforced portion) on the radially opposite side to the first straight portion 421 and the second straight portion 422 (the first reinforced portion). The inventors of the present invention have confirmed through analysis that when the portion with the lowest welding strength (the first straight portion 421 and the second straight portion 422) is reinforced, the portion (the second reinforced portion) on the radially opposite side of the reinforced portion becomes the portion with the second lowest welding strength. Therefore, by setting the portion as the second reinforced portion and providing the additional welding ribs 44 and the additional welding recesses 43 on the outer peripheral side thereof, the portion with insufficient welding strength can be reinforced.

[0060] In the present embodiment, the additional welding rib 44 includes a first portion 441 extending in a direction intersecting the welding rib 42 on the outer peripheral side of the welding rib 42. Therefore, the welding rib 42 can be prevented from tipping over by the first portion 441. In addition, since a gap S is provided between the end portion on the inner peripheral side of the first portion 441 and the welding rib 42, a space for accommodating welding burrs generated from the additional welding portion can be ensured.

[0061] In the present embodiment, the additional welding rib 44 includes: a first portion 441 disposed at two locations separated from each other in the circumferential direction; and a second portion 442 connecting the ends of the outer circumferential sides of the two first portions 441. In this way, by reinforcing the welding rib 42 at two locations, the welding rib 42 can be made less likely to tilt. In addition, by connecting the two additional welding ribs (first portions 441) by the second portion 442, the additional welding rib 44 as a whole can be made less likely to tilt. Therefore, the strength of the additional welding portion can be increased, and thus the reinforcement effect can be increased.

[0062] In the present embodiment, the housing 2 includes a mounting portion 24 disposed on the outer peripheral side 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 protrusions 31 and 32 protruding from the side wall portion 26 toward the outer peripheral side, and the mounting portion 24 is disposed on the outer peripheral side of the protrusions 31 and 32. The second fixing surface 33 includes a first region 34 formed by an end surface on the other side L2 of the axial direction of the side wall portion 26 and a second region 35 and 36 formed by an end surface on the other side L2 of the axial direction of the protrusions 31 and 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 region 35 and 36. Therefore, by providing the protrusions 31 and 32, the mounting portion 24 can be reinforced, and space for configuring the additional welding rib 44 for reinforcement on the end surfaces of the protrusions 31 and 32 can be ensured.

[0063] In the present embodiment, the housing 10 is provided with a reinforcing rib 46 connecting the outer peripheral surface of the main body 14 and the first flange portion 16, and the reinforcing rib 46 overlaps with the welding rib 42 when viewed from the axial direction. Therefore, the welding portion 40 can be reinforced. In addition, since the deformation of the first flange portion 16 can be suppressed by the reinforcing rib 46, the reduction in welding strength caused by the welding rib 42 not being able to fully contact the welding recess 41 due to the deformation of the first flange portion 16 can be suppressed. In the present embodiment, in order to make the bonding strength between the housing 2 and the first flange portion 16 uniform at all angular positions, the reinforcing rib 46 and the additional welding portion are provided.

[0064] In the present embodiment, the reinforcing rib 46 extends from the position overlapping with the welding rib 42 to the position overlapping with the additional welding rib 44 when viewed from the axial direction. Therefore, since the reinforcing rib 46 is provided so as to straddle the two welding portions, not only the welding portion 40 but also the additional welding portion can be reinforced, thereby improving the reinforcing effect. In addition, since the additional welding rib 44 is provided on the protrusions 17 and 18 that protrude greatly toward the outer peripheral side, the protrusions 17 and 18 that protrude greatly can be reinforced by extending the reinforcing rib 46 to the additional welding rib 44. Therefore, it is possible to suppress the reduction in welding strength caused by the deformation of the protrusions 17 and 18 causing the additional welding rib 44 to fail to fully contact with the additional welding recess 43.

[0065] (Other embodiments) (1) In the above embodiment, the welding rib 42 is provided on the second fixing surface 33, and the welding recess 41 is provided on the first fixing surface 19, but the concave and convex may be reversed. That is, the welding rib 42 may be provided on the first fixing surface 19, and the welding recess 41 may be provided on the second fixing surface 33.

[0066] (2) The above embodiment is a mode in which the additional welded parts (the additional welded concave part 43 and the additional welded rib 44) are provided at two locations, but the location and number of the additional welded parts are not limited to the location and number of the present invention. For example, the additional welded part may be provided at only one location on the outer peripheral side of the discharge port 22. Alternatively, the pressure applied to each part of the welded part 40 may be analyzed, and the additional welded part may be appropriately provided at the location that needs to be strengthened. In addition, it is also possible to provide only the welded part 40 without providing the additional welded part.

[0067] (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 may not overlap with the additional welding rib 44. In addition, a structure without providing the reinforcing rib 46 may be adopted.

[0068] (4) In the above embodiment, the discharge port 22 provided in the pump chamber 20 faces the same direction as the suction port 21 (one side L in the axial direction), but the direction of the discharge port 22 is not limited to such a direction. For example, the direction of the discharge port 22 may be the tangent direction of the downstream end of the flow path F. Explanation of symbols

[0069] 1 ... pump device, 2 ... housing, 3 ... motor, 4 ... impeller, 5 ... stator, 6 ... rotor, 7 ... support shaft, 8 ... substrate, 9 ... cover, 10 ... housing, 11 ... first partition wall, 12 ... second partition wall, 13 ... bottom wall, 14 ... main body, 15 ... connector housing, 16 ... first flange, 17, 18 ... protrusion, 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 recessed portion, 28 ... second recessed portion, 29 ... convex portion, 31, 32 ... protruding portion, 33 ... second fixing surface, 34 ... first region, 35, 36 ... second region, 40 ... welding portion, 41 ... welding recessed portion, 42 ... welding rib, 43 ... additional welding recessed portion, 44 ... additional welding rib, 46, 461, 462, 46 3… reinforcing rib, 50… coil, 51… stator core, 52, 53… insulator, 55… winding terminal, 60… rotor component, 61… magnet, 62… cylindrical portion, 63… flange portion, 64… blade portion, 65… plate, 66… circular hole, 70… radial bearing, 71… shaft hole, 72… support portion, 73… cylindrical portion, 74… thrust bearing, 90… opening portion, 91… heat dissipation component, 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… the other side in the axial direction, R1… one side in the circumferential direction, R2… the 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 pump device, characterized in that: have: A rotor and a stator surrounding the outer circumference of the rotor; a housing enclosing the stator; a housing covering the casing from one side along the axial direction of the rotation axis of the rotor and having a pump chamber forming portion that forms a pump chamber between the housing and the pump chamber forming portion; as well as an impeller disposed in the pump chamber and rotating integrally with the rotor, The shape of the pump chamber as viewed from the axial direction is a shape in which the width of a flow path extending in the circumferential direction on the outer periphery of the impeller increases toward one side in the circumferential direction. The housing includes: a first partition wall covering one side of the stator in the axial direction; a main body covering the outer periphery of the stator; and a first flange protruding from the main body toward the outer periphery. 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 opposite to the first fixing surface. One of the first fixing surface and the second fixing surface includes a welding rib extending along the outer shape of the pump chamber viewed from the axial direction, The other of the first fixing surface and the second fixing surface includes a welding recessed portion to which the welding rib is welded.

2. The pump device according to claim 1, characterized in that One of the first fixing surface and the second fixing surface includes an additional welding rib disposed on an outer peripheral side of the welding rib, The other of the first fixing surface and the second fixing surface includes an additional welding recessed portion to which the additional welding rib is welded.

3. The pump device according to claim 2, characterized in that The additional welding rib is arranged on the outer peripheral side of a portion where the welding rib extends linearly.

4. The pump device according to claim 2, characterized in that When the angular position at which the width of the flow path extending in the circumferential direction on the outer periphery of the impeller is the largest is set as the first angular position, and the angular position at which the width of the flow path is the smallest is set as the second angular position, The pump chamber forming portion includes: a suction port provided at the radial center of the pump chamber; and a discharge port provided at the first angular position, The welding rib includes a first reinforced portion, the first reinforced portion being arranged at one side of the first angular position in the circumferential direction within a first angular range to the second angular position, The additional welding rib and the additional welding recess are arranged on the outer peripheral side of the first reinforced portion.

5. The pump device according to claim 4, characterized in that The suction port and the discharge port open on one side in the axial direction.

6. The pump device according to claim 4, characterized in that The additional welding rib and the additional welding recess are arranged on the outer peripheral side of the first reinforced portion and on the outer peripheral side of the second reinforced portion on the opposite side to the first reinforced portion in the radial direction.

7. The pump device according to claim 2, characterized in that The additional welding rib includes a first portion extending in a direction intersecting the welding rib at the outer peripheral side of the welding rib, A gap is provided between the end portion on the inner peripheral side of the first portion and the welding rib.

8. The pump device according to claim 7, characterized in that The additional welding rib includes: the first portion disposed at two locations separated from each other in the circumferential direction; and a second portion connecting outer circumferential side ends of the two first portions.

9. The pump device according to claim 2, characterized in that The housing includes a mounting portion disposed on an outer peripheral 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 protrusion protruding from the side wall toward the outer peripheral side, wherein the mounting portion is arranged on the outer peripheral side of the protrusion, The second fixing surface includes: a first area formed by an end surface of the side wall portion on the other side of the axial direction; and a second region constituted by an end surface of the protrusion on the other side of the axial direction, The welding rib or the welding recess is arranged in the first region, The additional welding rib or the additional welding recess is provided in the second region.

10. The pump device according to claim 2, characterized in that The housing includes a reinforcement rib connecting the outer peripheral surface of the main body portion and the first flange portion, wherein the reinforcement rib overlaps the welding rib when viewed in the axial direction.

11. The pump device according to claim 10, characterized in that When viewed in the axial direction, the reinforcing rib extends from a position overlapping with the welding rib to a position overlapping with the additional welding rib.

Images