JP7569667B2 - Pumping equipment - Google Patents

Description

The present invention relates to a pump device equipped with a heat dissipation member.

In a pump device, an impeller located in a pump chamber is rotated by a motor. This type of motor has a stator covered by a partition member that divides the pump chamber, and a circuit board for supplying power to the motor is located on the opposite side of the stator from the impeller.

Such a pump device is described, for example, in Patent Document 1. In this document, the motor includes a rotor with an impeller disposed at one axial end, and a stator assembly surrounding the rotor. A driver that controls the motor is disposed on the other axial side of the stator assembly. The stator assembly is covered by a cylindrical body cover. The impeller is disposed on one axial side along which the central axis of rotation of the rotor extends. The driver is covered by a driver cover that seals the rear end of the body cover. The driver cover is fixed to the body cover by screws.

JP 2018-108024 A

In Patent Document 1, the driver cover fixed to the end of the pump device opposite the impeller has heat dissipation properties, and can dissipate heat from the driver that controls the motor. However, when using a heat dissipating material as the cover material for covering the circuit board of the pump device, a die-cast cover material has traditionally been used, but the manufacturing costs of die-cast cover materials are high. In addition, screws are used to fasten the die-cast cover material, so screw holes and screw attachment parts must be formed in the cover material and the mating material to which the cover material is fastened. This results in a problem of the overall size of the pump device.

In view of the above problems, the objective of the present invention is to provide a pump device that can be made low-cost and compact even when the heat dissipation properties of the cover member are improved.

In order to solve the above problems, the pump device according to the present invention has a rotor that rotates around a central axis of rotation, a stator arranged around the rotor, an impeller arranged on one side of the rotor in the axial direction along which the central axis of rotation extends, a resin sealing member that covers the stator and has a cylindrical portion that opens on the other side of the axial direction, a circuit board that is housed in the cylindrical portion and connected to the coil of the stator, and a cover member that covers the cylindrical portion from the other side, the cover member having a resin frame member with an opening that opens in the axial direction and a metal heat dissipation member that covers the opening, and a welding portion that joins the frame member and the cylindrical portion is provided between the frame member and the cylindrical portion.

In the present invention, the cover member that covers the tubular portion that houses the circuit board includes a resin frame member having an opening that opens in the axial direction, and a metal heat dissipation member that covers the opening. Therefore, compared to when the cover member is entirely made of metal, the parts cost can be reduced. In addition, since the frame member and the tubular portion are made of resin, the cover member can be fixed to the tubular portion of the resin sealing member by welding. Therefore, there is no need to use screws or the like to fix the cover member, and there is no need to form a portion for providing a screw hole in the cover member and the tubular portion. Therefore, it is possible to avoid an increase in the size of the cover member and the tubular portion, and the pump device can be made compact overall.

In the present invention, it is preferable that the welding portion comprises a welding protrusion provided on one of the frame member and the cylindrical portion and protruding in the axial direction, and a welding recess provided on the other of the frame member and the cylindrical portion into which the welding protrusion fits. With this configuration, the frame member and the cylindrical portion can be aligned by fitting the protrusion and the recess, making it easy to assemble the cover member and the cylindrical portion. In addition, since the protrusion can be welded to the recess, it is easy to fix the cover member to the cylindrical portion of the resin sealing member.

In the present invention, it is preferable that the cover member includes a seal member disposed between the frame member and the heat dissipation member. This configuration can improve the adhesion between the frame member and the heat dissipation member, thereby suppressing the deterioration of waterproofing caused by making the heat dissipation member and the frame member separate members.

In the present invention, the frame member includes a circular ring portion having the opening, and an annular wall portion protruding from the circular ring portion to the one side and fitting inside the tubular portion, and the heat dissipation member includes a shielding portion covering the opening from the one side, a peripheral wall portion bending and extending from the outer periphery of the shielding portion to the one side, and a flange portion protruding radially outward from the edge of the peripheral wall portion, and the sealing member is preferably disposed in the radial gap between the annular wall portion and the peripheral wall portion. With this configuration, it is possible to ensure airtightness by elastic deformation of the sealing member when the radial dimensional accuracy of the heat dissipation member and the frame member is low or when the dimensional accuracy is reduced due to temperature change.

In the present invention, it is preferable that the annular portion has an abutment portion that abuts against the shielding portion from the other side. With this configuration, the axial position of the shielding portion relative to the annular portion can be easily determined, and the heat dissipation member can be positioned axially relative to the frame member.

In the present invention, it is preferable that the heat dissipation member has a notch portion formed by cutting the outer periphery of the flange portion radially inward, and the annular wall portion has a positioning protrusion protruding radially inward, and the heat dissipation member is positioned in the circumferential direction by fitting the positioning protrusion into the notch portion. With this configuration, it is possible to restrict the rotation of the heat dissipation member relative to the frame member.

In the present invention, it is preferable that a heat transfer member is disposed between the heat dissipation member and the circuit board, the heat transfer member being in contact with the heat dissipation member and the circuit board. With this configuration, heat generated on the circuit board can be transferred to the heat dissipation member via the heat transfer member. This can therefore hasten heat dissipation and suppress temperature rise of the circuit board.

In the present invention, it is preferable that the heat transfer member contacts the electronic element placed on the circuit board. With this configuration, the heat from the electronic element that generates heat can be transferred directly to the heat dissipation member via the heat transfer member. This can speed up heat dissipation and suppress temperature rise of the electronic element.

In the present invention, the shielding portion includes a facing portion facing the electronic element and a flat portion surrounding the facing portion, the outer periphery of the flat portion abuts against the annular portion from the one side, the facing portion protrudes from the flat portion to the one side, and a contact avoidance space is preferably provided between the flat portion and the circuit board to avoid contact between the conductive material on the circuit board and the flat portion. With this configuration, the distance between the facing portion and the electronic element can be reduced, so that the thickness of the heat transfer member disposed between the facing portion and the electronic element can be reduced. This reduces the thermal resistance of the heat transfer member, so that the heat of the electronic element can be easily transferred to the heat dissipation member. In addition, a contact avoidance space can be provided between the flat portion and the circuit board, so that it is possible to prevent the shielding portion from accidentally coming into contact with the conductive material such as solder provided on the circuit board. This prevents the circuit board from being short-circuited.

In the present invention, the annular wall portion has a claw portion that fixes the outer peripheral end portion of the flange portion, and the claw portion is preferably formed by thermal caulking. With this configuration, the heat dissipation member can be easily fixed to the frame member.

In the present invention, it is preferable that the inner peripheral surface of the annular wall portion has a step portion that restricts the movement of the seal member to the other side. With this configuration, it is possible to prevent the seal member from shifting to the other side, thereby improving the sealing performance of the radial gap between the annular wall portion and the peripheral wall portion.

In the present invention, it is preferable that the annular portion has an outer surface facing the other side, and the outer surface has a plurality of gate marks arranged in an area overlapping with the annular wall portion in the axial direction. With this configuration, molding defects in the annular wall portion can be suppressed when the frame member is injection molded.

In the present invention, the cover member comprises a resin frame member with an opening that opens in the axial direction, and a metal heat dissipation member that covers the opening. This allows parts costs to be reduced compared to when the cover member is molded by metal die casting. In addition, since the frame member and the cylindrical portion are fixed by welding, there is no need to form screw holes in the cover member and the cylindrical portion. This allows the pump device to be made compact overall.

1 is a perspective view of a pump device to which the present invention is applied; 2 is a perspective view of the pump device shown in FIG. 1 as viewed from the other side. FIG. FIG. 2 is a cross-sectional view of the pump device shown in FIG. 2 is an enlarged sectional perspective view of the other end of the pump device shown in FIG. 1 . FIG. FIG.

The pump device equipped with the impeller according to the present invention will be described below with reference to the drawings. In the following description, the direction in which the central axis of rotation L extends will be described as the axial direction. In the axial direction, one side will be labeled L1 and the other side will be labeled L2. In the following description, the radial direction and circumferential direction around the central axis of rotation will be referred to simply as the "radial direction" and the "circumferential direction", respectively.

(Overall composition)
Fig. 1 is a perspective view of a pump device 1 to which the present invention is applied. Fig. 2 is a perspective view of the pump device 1 shown in Fig. 1 as viewed from the other side L2. Fig. 3 is a cross-sectional view of the pump device 1 shown in Fig. 1. Fig. 4 is an enlarged cross-sectional perspective view of an end portion of the other side L2 of the pump device 1 shown in Fig. 1. Fig. 5 is a perspective view of a cover member. Fig. 6 is an exploded perspective view of the cover member.

As shown in Figures 1 to 3, the pump device 1 comprises a case 2, a motor 3 equipped with a rotor 5 and a stator 6, and a resin impeller 4 arranged on one axial side L1 of the rotor 5. The case 2 houses the impeller 4 and defines a pump chamber 20. The motor 3 comprises a resin sealing member 7 that covers the stator 6, a circuit board 8 connected to the coil 63 of the stator 6, and a cover member 9 that covers the circuit board 8 from the other side L2. The pump device 1 moves the fluid in the pump chamber 20 by rotating the impeller 4 together with the rotor 5 about the central axis of rotation L.

(case)
As shown in Fig. 3, the case 2 defines a pump chamber 20 between the case 2 and the resin sealing member 7. The case 2 includes an opposing wall 23 opposing the impeller 4 on one side L1, and a side wall 24 extending in the circumferential direction on the radially outer side of the impeller 4. As shown in Figs. 1 and 2, the case 2 includes a suction pipe 21 extending along the axial direction, and a discharge pipe 22 extending in a direction perpendicular to the axial direction. The suction pipe 21 and the discharge pipe 22 include a suction port 21a and a discharge port 22a at their ends, respectively. The suction pipe 21 and the suction port 21a are provided concentrically with respect to the central axis L of rotation. The discharge pipe 22 is located radially outward of the impeller 4.

(Impeller)
The impeller 4 is made of resin. As shown in Fig. 3, the impeller 4 includes a circular first plate 41, a plurality of blades 42 that protrude from the first plate 41 to one side L1 and are arranged at regular intervals in the circumferential direction, and a circular second plate 43 that abuts against the tips of the blades 42 on the other side L2. When the impeller 4 rotates integrally with the rotor 5 about the central axis L of rotation by the driving of the motor 3, the blades 42 cause the fluid in the pump chamber 20 to flow in the rotational direction. As a result, centrifugal force is generated in the fluid, which is low-pressure on the radial inside and high-pressure on the radial outside, and is sucked in through the suction port 21a and discharged through the discharge port 22a.

(Motor)
As shown in Fig. 3, the rotor 5 includes a cylindrical holder 51 extending in the axial direction and a cylindrical magnet 10 held on the outer circumferential surface of the holder 51. The holder 51 is made of resin. The holder 51 includes a small diameter portion 52 that holds the magnet 10 on its outer circumferential surface, a circular abutment portion 53 that abuts against the end of the magnet 10 on the other side L2, and a large diameter portion 54 that protrudes from the outer circumferential edge of the abutment portion 53 to the one side L1, and the outer diameter dimension of the small diameter portion 52 is smaller than the outer diameter dimension of the large diameter portion 54. The small diameter portion 52 and the large diameter portion 54 are provided coaxially. The small diameter portion 52 holds a bearing 56 therein, and the rotor 5 is rotatably supported by the support shaft 11 via the bearing 56.

As shown in FIG. 3, the magnet 10 is entirely covered with a resin skin layer. The outer diameter of the magnet 10 is approximately the same as the outer diameter of the large diameter portion 54. The magnet 10 and the small diameter portion 52 are bonded together by applying an adhesive between them. At this time, the magnet 10 is positioned in the axial direction by abutting against the abutment portion 53. The magnet 10 is composed of a ferrite magnet, a neodymium bonded magnet, a samarium iron nitrogen magnet, or the like. In this embodiment, the magnet 10 is a ferrite magnet. Note that when the magnet 10 is a ferrite magnet, it does not have to be entirely covered with a resin skin layer.

As shown in FIG. 3, the stator 6 has a stator core 61 and a coil 63 wound around the stator core 61 via an insulator 62. Although detailed description is omitted, the stator core 61 has an annular portion surrounding the rotor 5 and a plurality of salient poles protruding radially inward from the annular portion. The coil 63 is wound between a first flange portion 621 on the radial inner side of the insulator 62 that covers the salient poles and a second flange portion 622 on the radial outer side. In this embodiment, the motor 3 is a three-phase motor, and the coil 63 includes a U-phase coil, a V-phase coil, and a W-phase coil.

3 and 4, the resin sealing member 7 includes a first partition portion 71 interposed between the stator 6 and the impeller 4, a second partition portion 72 interposed between the stator 6 and the magnet 10, and a third partition portion 73 facing the end face of the other side L2 of the rotor 5. The first partition portion 71 faces the impeller 4 on the other side L2, and defines a pump chamber 20 between the case 2. In this embodiment, the resin sealing member 7 is a resin sealing member that covers the stator 6 from the radial outside and the radial inside, as well as from both sides in the axial direction. The material of the resin sealing member 7 is, for example, polyphenylene sulfide (PPS: Poly Phenylene Sulfide) by insert molding the stator 6. Also, for example, the resin sealing member 7 may be formed by insert molding the stator 6 using BMC (Bulk Molding Compound) or the like.

As shown in FIG. 3, the support shaft 11 is a rod-shaped member made of metal. The central axis of the support shaft 11 coincides with the central axis of rotation L of the rotor 5. The end of the other side L2 of the support shaft 11 is press-fitted into a hole 73a formed in the third partition wall 73. An annular plate member 12 is attached to the end of one side L1 of the support shaft 11. The plate member 12 abuts against the end of the other side L2 of the bearing 56.

The resin sealing member 7 has a cylindrical portion 74 that opens to the other side L2 at the end of the other side L2 of the pump device 1. In this embodiment, the third partition wall portion 73 expands from the other side L2 of the rotor 5 toward the outer periphery and covers the other side L2 of the stator 6. The cylindrical portion 74 has a small diameter portion 75 that connects to the third partition wall portion 73, a large diameter portion 76 that connects to the end of the other side L2 of the small diameter portion 75, and a flange portion 77 that protrudes radially outward from the end of the other side L2 of the large diameter portion 76. The cylindrical portion 74 also has a connector housing 78 that covers a connector pin 82 that is electrically connected to the circuit board 8. The small diameter portion 75 is cylindrical. The large diameter portion 76 is cylindrical and has a larger outer diameter than the small diameter portion 75. The circuit board 8 is housed inside the large diameter portion 76. The flange portion 77 is provided around the entire circumference of the large diameter portion 76.

The resin sealing member 7 has a mounting portion 79 for mounting the circuit board 8. The mounting portion 79 protrudes from the third partition portion 73 to the other side L2. When viewed from the axial direction, the mounting portion 79 has a circular shape, and the central axis of the mounting portion 79 coincides with the central axis of rotation L. A crimping portion 791 for fixing the circuit board 8 is provided on the end face of the other side L2 of the mounting portion 79. The crimping portion 791 is formed by thermally deforming the tip of the protruding portion 791a protruding from the end face of the other side L2 of the mounting portion 79. In other words, the crimping portion 791 is formed by thermal crimping.

3 and 4, the circuit board 8 is provided with a circuit for controlling the power supply to the coil 63. The circuit board 8 is placed on the end face of the other side L2 of the mounting portion 79 from the other side L2, and is fixed to the mounting portion 79 by a fixing member 791. More specifically, a through hole 8a is provided in the center of the circuit board 8 at a position overlapping with the mounting portion 79 when viewed from the axial direction. With the protrusion 791a inserted into the through hole 8a, the tip of the protrusion 791a is thermally crimped, and the circuit board 8 is fixed to the mounting portion 79 by the crimped portion 791 formed at the tip of the protrusion 791a. The circuit board 8 is provided with an engagement portion (not shown) on the outer periphery. The circuit board 8 is positioned in the circumferential direction by the engagement of the engagement portion with the tube portion 74. An electronic element 81 is mounted on the surface of the other side L2 of the circuit board 8. The electronic element 81 is an IC chip or the like that controls the power supply. The electronic element 81 becomes a heat source that generates heat when controlling the power supply to the coil 63.

3 to 6, the cover member 9 is fixed to the flange portion 77 of the resin sealing member 7 by welding, and covers the tube portion 74 from the other side L2. The cover member 9 includes a resin frame member 91 having an opening 91a that opens in the axial direction, a metal heat dissipation member 92 that covers the opening 91a from the one side L1, and a seal member 93 that is disposed between the frame member 91 and the heat dissipation member 92. In addition, a heat transfer member 15 is disposed between the heat dissipation member 92 and the circuit board 8, which transfers heat from the circuit board 8 to the heat dissipation member 92 by coming into contact with the heat dissipation member 92 and the circuit board 8.

The frame member 91 includes a plate-shaped annular portion 911 with a circular opening 91a, and an annular wall portion 912 that protrudes from the annular portion 911 to one side L1 at the radial center of the annular portion 911. The outer shape of the annular portion 911 is the same as the outer shape of the flange portion 77 of the tube portion 74. The annular portion 911 includes an outer surface 913 facing the other side L2, an inner surface inner peripheral portion 914 facing the one side L1 radially inward from the annular wall portion 912, and an inner surface outer peripheral portion 915 facing the one side L1 radially outward from the annular wall portion 912. The outer surface 913 includes a plurality of gate marks G formed when the frame member 91 is injection molded at a position overlapping with the annular wall portion 912 in the axial direction. The inner surface outer peripheral portion 915 faces the flange portion 77 from the other side L2.

As shown in FIG. 4, the annular wall portion 912 is located inside the large diameter portion 76 of the tube portion 74. The outer peripheral surface of the annular wall portion 912 abuts against the inner peripheral surface of the large diameter portion 76 of the tube portion 74. As shown in FIG. 6, the annular wall portion 912 has a positioning protrusion 917 that protrudes radially inward. When viewed from the axial direction, the positioning protrusion 917 has a semicircular shape and extends in the axial direction. The positioning protrusions 917 are provided at eight locations at equal intervals in the circumferential direction. As described later, a claw portion 919 is formed at the tip of one side L1 of each positioning protrusion 917. In addition, the inner peripheral surface of the annular wall portion 912 has a step portion 918 that is recessed toward the other side L2. The step portion 918 extends around the entire circumference along the inner peripheral surface of the annular wall portion 912. The step portion 918 restricts movement of the seal member 93 to the other side L2 and positions the seal member 93 in the axial direction.

The heat dissipation member 92 is located radially inside the annular wall portion 912. The heat dissipation member 92 is composed of a single metal plate. The heat dissipation member 92 is composed of a metal such as copper, brass, or aluminum. When viewed from the axial direction, the heat dissipation member 92 is circular. The heat dissipation member 92 includes a shielding portion 921 that covers the opening 91a from one side L1, a peripheral wall portion 922 that bends from the outer periphery of the shielding portion 921 to one side L1 and extends in the axial direction, and a flange portion 923 that protrudes radially outward from the edge of the peripheral wall portion 922.

When viewed from the axial direction, the shielding portion 921 has a circular shape and has a larger outer diameter than the opening 91a. The shielding portion 921 abuts against the inner surface inner periphery 914 from one side L1 in the axial direction. In other words, the inner surface inner periphery 914 is an abutment portion that abuts against the shielding portion 921 from the other side L2, and functions as a positioning portion 916 that positions the shielding portion 921 in the axial direction.

The shielding portion 921 has a planar portion 924 that faces the circuit board 8, and a facing portion 925 that protrudes from the planar portion 924 to one side L1. The facing portion 925 has a rectangular shape when viewed in the axial direction, and overlaps with the electronic element 81 in the axial direction. Since the planar portion 924 is disposed at a position set back from the facing portion 925 to the other side L2, a contact avoidance space S is formed between the planar portion 924 and the circuit board 8 to avoid contact between the planar portion 924 and conductive materials such as solder on the circuit board 8.

The heat dissipation member 92 has cutouts 926 formed by cutting the outer periphery of the flange portion 923 toward the inner periphery. When viewed from the axial direction, the cutouts 926 are semicircular. The cutouts 926 are provided at eight locations at equal intervals in the circumferential direction. When the heat dissipation member 92 is fixed to the frame member 91, the peripheral wall portion 922 of the heat dissipation member 92 is inserted into the inner periphery of the annular wall portion 912 of the frame member 91, and at this time, the cutouts 926 engage with positioning protrusions 917 provided on the inner periphery of the annular wall portion 912. This positions the heat dissipation member 92 in the circumferential direction.

5 and 6, the frame member 91 has a claw portion 919 provided at the tip of one side L1 of the annular wall portion 912. The claw portion 919 overlaps with the positioning protrusion 917 in the axial direction. The claw portion 919 is formed by thermally deforming a deformation portion 919a protruding from the tip of the one side L1 of the annular wall portion 912. In other words, the claw portion 919 is a crimped portion formed by thermal crimping. The claw portion 919 engages the outer circumferential edge of the flange portion 923 from the one side L1. In this way, the heat dissipation member 92 is fixed to the frame member 91.

The seal member 93 is disposed between the frame member 91 and the heat dissipation member 92, and is in close contact with the frame member 91 and the heat dissipation member 92. In this embodiment, the seal member 93 is an O-ring. The seal member 93 is disposed in the radial gap between the annular wall portion 912 and the peripheral wall portion 922, and is in close contact with the inner circumferential surface of the annular wall portion 912 and the outer circumferential surface of the peripheral wall portion 922 in a state where it is elastically deformed in the radial direction. In addition, the movement of the seal member 93 to the other side L2 is restricted by the step portion 918.

The heat transfer member 15 is a thin sheet-like heat transfer member that has elasticity. The heat transfer member 15 may be grease or the like. In this embodiment, the heat transfer member 15 is disposed so as to be in contact with the facing portion 925 and the electronic element 81.

The cover member 9 is fixed to the cylindrical portion 74 of the resin sealing member 7 by welding. In this embodiment, a welding portion 94 that joins the frame member 91 and the cylindrical portion 74 is provided between the frame member 91 and the cylindrical portion 74. The welding portion 94 is provided at a location where the flange portion 77 provided at the end of the other side L2 of the cylindrical portion 74 and the annular portion 911 of the frame member 91 face each other in the axial direction. As shown in FIG. 4, the frame member 91 has a welding protrusion 951 that protrudes from the inner peripheral portion 915 of the annular portion 911 to the one side L1. The welding protrusion 951 is annular and surrounds the periphery of the annular wall portion 912. The flange portion 77 has an annular welding recess 952 that faces the welding protrusion 951 from the one side L1. Alternatively, a configuration may be adopted in which the frame member 91 has a recessed welding portion on the other side L2, and the flange portion 77 has a protruding welding portion that protrudes on the other side L2.

Next, a welding method for fixing the cover member 9 to the resin sealing member 7 will be described. As the welding method, ultrasonic welding, vibration welding, etc. are used. In this embodiment, with the welding convex portion 951 fitted into the welding concave portion 952, a welding head is pressed against the outer surface 913 of the annular portion 911 to weld the welding convex portion 951 and the welding concave portion 952. During welding, the flange portion 77 is supported from one side L2 by a jig. In this embodiment, the resin sealing member 7 has a connector housing 78 that protrudes radially outward from the tube portion 74, and an axial gap is formed between the flange portion 77 and the connector housing 78 into which a jig can be inserted. In this embodiment, the heat transfer member 15 is reliably brought into contact with the facing portion 925 and the electronic element 81 by adjusting the amount of welding between the frame member 91 and the tube portion 74.

(Action and Effect)
As described above, the pump device 1 of this embodiment includes the rotor 5 that rotates around the rotation axis L, the stator 6 arranged around the rotor 5, the impeller 4 arranged on one side L1 in the axial direction along which the rotation axis L extends relative to the rotor 5, the resin sealing member 7 that covers the stator 6 and has a cylindrical portion 74 that opens on the other side L2 in the axial direction, the circuit board 8 that is housed in the cylindrical portion 74 and connected to the coil 63 of the stator 6, and the cover member 9 that covers the cylindrical portion 74 from the other side L2. The cover member 9 includes a resin frame member 91 that has an opening 91a that opens in the axial direction, and a metal heat dissipation member 92 that covers the opening 91a. Between the frame member 91 and the cylindrical portion 74, a welding portion 94 that joins the frame member 91 and the cylindrical portion 74 is provided.

With this configuration, the cost of parts can be reduced compared to when the cover member 9 is entirely made of metal. In addition, since the frame member 91 and the tubular portion 74 are made of resin, the cover member 9 can be fixed to the tubular portion 74 of the resin sealing member 7 by welding. Therefore, it is not necessary to use screws or the like to fix the cover member 9, and it is not necessary to form screw holes in the cover member 9 and the tubular portion 74. Therefore, it is possible to avoid increasing the size of the cover member 9 and the tubular portion 74, and the pump device 1 can be made compact overall. Furthermore, by fixing by welding, it is possible to adjust the axial position of the cover member 9. Therefore, it is possible to finely adjust the axial distance between the heat dissipation member 92 provided on the cover member 9 and the circuit board 8. In addition, by changing the material of the metal used for the heat dissipation member 92, the heat dissipation effect of the heat dissipation member 92 can be easily changed. For example, if the material of the heat dissipation member 92 is copper, the heat dissipation effect of the heat dissipation member 92 can be increased.

In this embodiment, the welding portion 94 includes a welding protrusion 951 provided on the frame member 91 and protruding to one side L1, and a welding recess 952 provided on the tubular portion 74 into which the welding protrusion 951 fits. Therefore, the frame member 91 and the tubular portion 74 can be aligned by fitting the welding protrusion 951 and the welding recess 952 together, making it easy to assemble the cover member 9 and the tubular portion 74. In addition, the welding protrusion 951 can be welded to the welding recess 952, making it easy to fix the cover member 9 to the tubular portion 74 of the resin sealing member 7.

In this embodiment, the cover member 9 includes a seal member 93 disposed between the frame member 91 and the heat dissipation member 92. This improves the adhesion between the frame member 91 and the heat dissipation member 92, thereby preventing water and other substances from entering the tube portion 74 from the cover member 9, thereby improving waterproofing.

In this embodiment, the frame member 91 includes an annular ring portion 911 having an opening 91a, and an annular wall portion 912 that protrudes from the annular ring portion 911 to one side L1 at the radial center of the annular ring portion 911 and fits inside the tube portion 74. The heat dissipation member 92 includes a shielding portion 921 that covers the opening 91a from one side L1, a peripheral wall portion 922 that bends from the outer periphery of the shielding portion 921 to one side L1 and extends in the axial direction, and a flange portion 923 that protrudes radially outward from the edge of the peripheral wall portion 922. The heat dissipation member 92 is located radially inside the annular wall portion 912, and the seal member 93 is disposed in a radial gap between the annular wall portion 912 and the peripheral wall portion 922. Therefore, when the radial dimensional accuracy of the heat dissipation member 92 and the frame member 91 is low, or when the dimensional accuracy decreases due to temperature changes, the sealing member 93 can be elastically deformed to ensure airtightness.

In this embodiment, the annular portion 911 has an inner surface inner periphery 914 which is an abutment portion that abuts against the shielding portion 921 from the other side L2, and the inner surface inner periphery 914 functions as a positioning portion 916 that positions the shielding portion 921 in the axial direction. Therefore, the axial position of the shielding portion 921 relative to the annular portion 911 can be easily determined, and the heat dissipation member 92 can be positioned in the axial direction relative to the frame member 91.

In this embodiment, the heat dissipation member 92 has a notch portion 926 formed by cutting the outer peripheral edge of the flange portion 923 radially inward. The annular wall portion 912 has a positioning protrusion 917 that protrudes radially inward. The heat dissipation member 92 has a circumferential position fixed by fitting the notch portion 926 into the positioning protrusion 917, so that the heat dissipation member 92 can be prevented from rotating relative to the frame member 91.

In this embodiment, a heat transfer member 15 that contacts the heat dissipation member 92 and the circuit board 8 is disposed between the heat dissipation member 92 and the circuit board 8. Therefore, heat generated in the circuit board 8 can be transferred to the heat dissipation member 92 via the heat transfer member 15. This can hasten heat dissipation and suppress a rise in temperature of the circuit board 8.

In this embodiment, the heat transfer member 15 contacts the electronic element 81 arranged on the circuit board 8. Therefore, the heat of the heat-generating electronic element 81 can be directly transferred to the heat dissipation member 92 via the heat transfer member 15. This can hasten heat dissipation and suppress a temperature rise of the electronic element 81.

In this embodiment, the shielding portion 921 includes a facing portion 925 facing the electronic element 81 and a flat portion 924 surrounding the facing portion 925. The outer peripheral edge of the flat portion 924 abuts against the annular portion 911 of the frame member 91 from one side L1. A contact avoidance space S is formed between the flat portion 924 and the circuit board 8 to avoid contact between the conductive material on the circuit board 8 and the flat portion 924. Therefore, since the distance between the facing portion 925 and the electronic element 81 is small, the thickness of the heat transfer member 15 disposed between the facing portion 925 and the electronic element 81 can be made thin. As a result, the thermal resistance of the heat transfer member 15 is small, so that the heat of the electronic element 81 can be easily transferred to the heat dissipation member 92. In addition, since a contact avoidance space S can be provided between the flat portion 924 and the circuit board 8, it is possible to prevent the shielding portion 921 from accidentally coming into contact with the conductive material such as solder provided on the circuit board 8. This makes it possible to prevent the circuit board 8 from being short-circuited.

In this embodiment, the annular wall portion 912 has a claw portion 919 that fixes the outer peripheral end of the flange portion 923, and the claw portion 919 is formed by thermally deforming a deformation portion 919a provided at the tip portion. Therefore, the heat dissipation member 92 can be easily fixed to the frame member 91 by thermal caulking.

In this embodiment, the inner peripheral surface of the annular wall portion 912 has a step portion 918 that restricts the movement of the seal member 93 to the other side L2, so that the seal member 93 can be prevented from shifting to the other side L2. This improves the sealing performance of the radial gap between the annular wall portion 912 and the peripheral wall portion 922, thereby improving the waterproof performance.

In this embodiment, the annular portion 911 has an outer surface 913 facing the other side L2. The outer surface 913 has a plurality of gate marks G arranged in an area that overlaps with the annular wall portion 912 in the axial direction. By providing the gates in such positions, it is possible to suppress a decrease in molding accuracy when injection molding the frame member 91. Therefore, molding defects of the annular wall portion 912 can be suppressed.

1...pump device, 2...case, 3...motor, 4...impeller, 5...rotor, 6...stator, 7...resin sealing member, 8...circuit board, 8a...through hole, 9...cover member, 10...magnet, 11...support shaft, 12...plate member, 15...heat transfer member, 20...pump chamber, 21...suction pipe, 21a...suction port, 22...discharge pipe, 22a...discharge port, 23...opposing wall, 24...side wall, 4 Reference Signs List 1...first plate, 42...blade portion, 43...second plate, 51...holder, 52...small diameter portion, 53...contact portion, 54...large diameter portion, 56...bearing, 61...stator core, 62...insulator, 63...coil, 71...first partition wall portion, 72...second partition wall portion, 73...third partition wall portion, 73a...hole portion, 74...tubular portion, 75...small diameter portion, 76...large diameter portion, 77...flange portion, 78... Connector housing, 79... mounting portion, 81... electronic element, 82... connector pin, 91a... opening, 91... frame member, 92... heat dissipation member, 93... sealing member, 94... welding portion, 621... first flange portion, 622... second flange portion, 791... crimping portion, 791a... protrusion portion, 911... ring portion, 912... annular wall portion, 913... outer surface, 914... inner surface inner periphery portion, 915... inner surface outer periphery portion, 916...positioning portion, 917...positioning protrusion, 918...step portion, 919...claw portion, 919a...deformation portion, 921...shielding portion, 922...peripheral wall portion, 923...flange portion, 924...flat portion, 925...facing portion, 926...notch portion, 951...welding protrusion, 952...welding recess, G...gate mark, L...rotation center axis, L1...one side, L2...other side, S...contact avoidance space

Claims (11)

A rotor that rotates around a central axis of rotation;
A stator disposed around the rotor;
an impeller disposed on one side of the rotor in an axial direction in which the central axis of rotation extends;
a resin sealing member covering the stator and including a cylindrical portion that opens on the other side in the axial direction;
a circuit board housed in the cylindrical portion and connected to a coil of the stator;
a cover member that covers the cylindrical portion from the other side,
the cover member includes a resin frame member having an opening portion that opens in the axial direction, and a metal heat dissipation member that covers the opening portion,
a welding portion that joins the frame member and the cylindrical portion is provided between the frame member and the cylindrical portion ,
the cover member includes a seal member disposed between the frame member and the heat dissipation member,
the frame member includes a circular ring portion having the opening, and an annular wall portion protruding from the circular ring portion to the one side and fitted inside the cylindrical portion,
the heat dissipation member includes a shielding portion that covers the opening from the one side, a peripheral wall portion that bends and extends from an outer circumferential edge of the shielding portion toward the one side, and a flange portion that protrudes radially outward from an end edge of the peripheral wall portion,
the sealing member is disposed in all radial gaps between the annular wall portion and the peripheral wall portion, and in a state where it is elastically deformed in the radial direction, it is in close contact with an inner circumferential surface of the annular wall portion and an outer circumferential surface of the peripheral wall portion;
the annular wall portion includes a claw portion for fixing an outer peripheral end portion of the flange portion,
The pump device is characterized in that the claw portion is formed by thermal caulking . A rotor that rotates around a central axis of rotation;
A stator disposed around the rotor;
an impeller disposed on one side of the rotor in an axial direction in which the central axis of rotation extends;
a resin sealing member covering the stator and including a cylindrical portion that opens on the other side in the axial direction;
a circuit board housed in the cylindrical portion and connected to a coil of the stator;
a cover member that covers the cylindrical portion from the other side,
the cover member includes a resin frame member having an opening portion that opens in the axial direction, and a metal heat dissipation member that covers the opening portion,
a welding portion that joins the frame member and the cylindrical portion is provided between the frame member and the cylindrical portion ,
the cover member includes a seal member disposed between the frame member and the heat dissipation member,
the frame member includes a circular ring portion having the opening, and an annular wall portion protruding from the circular ring portion to the one side and fitted inside the cylindrical portion,
the heat dissipation member includes a shielding portion that covers the opening from the one side, a peripheral wall portion that bends and extends from an outer circumferential edge of the shielding portion toward the one side, and a flange portion that protrudes radially outward from an end edge of the peripheral wall portion,
the seal member is disposed in a radial gap between the annular wall portion and the peripheral wall portion,
a heat transfer member is disposed between the heat dissipation member and the circuit board, the heat transfer member being in contact with the heat dissipation member and the circuit board;
the heat transfer member contacts an electronic element disposed on the circuit board;
the shielding portion includes a facing portion facing the electronic element and a planar portion surrounding the facing portion,
an outer circumferential edge of the flat portion abuts against the annular portion from the one side;
The facing portion protrudes from the planar portion to the one side,
A pump device according to claim 1, wherein a contact avoidance space is provided between the flat portion and the circuit board to prevent contact between a conductive material on the circuit board and the flat portion . 3. The pump device according to claim 1,
the welding portion includes a welding convex portion provided on one of the frame member and the cylindrical portion and protruding in the axial direction, and a welding concave portion provided on the other of the frame member and the cylindrical portion, into which the welding convex portion fits. The pump device according to any one of claims 1 to 3 ,
The pump device according to claim 1, wherein the annular portion has an abutment portion that abuts against the shielding portion from the other side. The pump device according to any one of claims 1 to 4 ,
The heat dissipation member includes a notch portion formed by cutting an outer circumferential edge of the flange portion radially inward,
The annular wall portion includes a positioning protrusion protruding radially inward,
The pump device according to claim 1, wherein the heat dissipating member is positioned in a circumferential direction by the positioning protrusions fitting into the cutouts. 2. The pump device according to claim 1 ,
A pump device, comprising: a heat transfer member disposed between the heat dissipation member and the circuit board, the heat transfer member being in contact with the heat dissipation member and the circuit board. 7. The pump device according to claim 6 ,
The pump device, wherein the heat transfer member is in contact with an electronic element disposed on the circuit board. 8. The pump device according to claim 7 ,
the shielding portion includes a facing portion facing the electronic element and a planar portion surrounding the facing portion,
an outer circumferential edge of the flat portion abuts against the annular portion from the one side;
The facing portion protrudes from the planar portion to the one side,
A pump device according to claim 1, wherein a contact avoidance space is provided between the flat portion and the circuit board to prevent contact between a conductive material on the circuit board and the flat portion. A pump device according to any one of claims 1 to 8 ,
the annular wall portion includes a claw portion for fixing an outer peripheral end portion of the flange portion,
The pump device is characterized in that the claw portion is formed by thermal caulking. 9. The pump device according to claim 5 or 8 ,
The pump device according to claim 1, wherein an inner circumferential surface of the annular wall portion is provided with a step portion that restricts movement of the seal member to the other side. A pump device according to any one of claims 1 to 10 ,
The annular portion has an outer surface facing the other side,
The pump device is characterized in that the outer surface has a plurality of gate marks arranged in a region overlapping with the annular wall portion in the axial direction.

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