CN211975417U

CN211975417U - Pump device

Info

Publication number: CN211975417U
Application number: CN202020493757.XU
Authority: CN
Inventors: 仓谷大树; 小窪信树; 山本岳
Original assignee: Nidec Sankyo Corp
Current assignee: Nidec Instruments Corp
Priority date: 2019-04-11
Filing date: 2020-04-07
Publication date: 2020-11-20
Anticipated expiration: 2030-04-07
Also published as: CN211975418U; CN111810413B; CN111810413A; JP2020172922A; JP2020172923A

Abstract

A pump device is provided with a resin sealing component covering a stator and a circuit substrate, and can inhibit the circuit substrate from warping even if the injection pressure of a resin material injected into a mold is increased when the resin sealing component is formed. The pump device is provided with a circuit board (4) fixed on the partition wall (11a) on the Z2 direction side of the partition wall (11a), and a resin sealing member made of resin for covering the stator (6) and the circuit board. The circuit board is disposed on the Z2 direction side of the stator core (24). The insulating member (25) is provided with a wall portion (25a) that stands from the stator core (24) toward the Z2 direction side. A gate mark is formed on the outer peripheral surface of the resin sealing member in the Y1 direction, and the wall portion (25a) is disposed at the end of the stator (6) on the Y1 direction side. The end surface of the wall portion (25a) on the Z2 direction side is in contact with the surface of the circuit board on the Z1 direction side, and the circuit board is fixed to the wall portion (25 a).

Description

Pump device

Technical Field

The utility model relates to a stator and circuit substrate are by pump unit of resin seal part cover.

Background

Conventionally, a pump device including an impeller and a rotor disposed in a pump chamber, and a stator and a circuit board disposed outside the pump chamber is known (for example, see patent document 1). In the pump device described in patent document 1, a bottomed cylindrical partition member that prevents a fluid from flowing into a portion where the stator and the circuit board are disposed is disposed between the stator and the circuit board and the pump chamber. The stator and the circuit board are covered with a resin sealing member. The stator is formed in a substantially cylindrical shape. The rotor is disposed on the inner periphery side of the stator.

In the pump device described in patent document 1, the stator includes a plurality of driving coils, a plurality of insulators, and a stator core around which the driving coils are wound via the insulators. The stator core includes an outer circumferential ring portion formed in an annular shape and a plurality of salient pole portions protruding radially inward from the outer circumferential ring portion. The insulator includes an axial covering portion that covers a part of the outer peripheral ring portion from below. At the front end of the stator, a gap is formed between the axially covering portions adjacent in the circumferential direction of the rotor.

In the pump device described in patent document 1, the circuit board is disposed below the bottom of the partition member. The circuit board is fixed to the partition member. The circuit board is disposed below the lower end of the axial covering portion, and a gap is formed between the lower end of the axial covering portion and the upper surface of the circuit board. A gate mark is formed at the front end of the outer peripheral surface of the resin sealing member. The lower end of the gate mark is disposed below the lower surface of the circuit board, and the upper end of the gate mark is disposed above the lower end of the outer peripheral ring portion of the stator core. An intermediate portion of the gate mark in the up-down direction is arranged to a front side of a gap formed between the axially covering portions adjacent in the circumferential direction of the rotor.

In manufacturing the pump device described in patent document 1, the partition member, the stator, and the circuit board are placed in a mold with the partition member inserted into the inner periphery of the stator and the circuit board fixed to the partition member, and a resin material is injected into the mold from the front side of the stator and cured to form a resin sealing member covering the stator and the circuit board. The gate mark of the mold used for forming the resin seal member is a gate mark formed at the tip of the outer peripheral surface of the resin seal member.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2017-216758

SUMMERY OF THE UTILITY MODEL

Technical problem to be solved by the utility model

In the pump device described in patent document 1, the circuit board is disposed below the lower end of the axial covering portion. In addition, in the pump device, an intermediate portion of the gate mark in the up-down direction is arranged to a front side of a gap formed between the axially covering portions adjacent in the circumferential direction of the rotor. Therefore, in the case of such a pump device, if the injection pressure of the resin material injected into the mold is increased when the resin sealing member is formed, after the resin material starts to be injected into the mold, the resin material injected into the mold from the front side of the stator first enters the upper surface side of the circuit board, and there is a possibility that the circuit board fixed to the partition member is pressed downward. Further, if the circuit board fixed to the partition member is pressed downward immediately after the resin material is injected into the mold, the circuit board may warp downward, which may cause various problems such as damage to electronic components mounted on the circuit board and soldered portions of the circuit board.

Accordingly, an object of the present invention is to provide a pump device including a resin sealing member covering a stator and a circuit board, which can suppress warpage of the circuit board even when an injection pressure of a resin material injected into a mold is increased when the resin sealing member is formed.

Technical scheme for solving technical problem

In order to solve the above technical problem, the utility model discloses a pump device's characterized in that possesses: an impeller; a rotor having a drive magnet and an impeller attached thereto; a stator formed in a cylindrical shape and disposed on an outer peripheral side of the rotor, and having a driving coil; a partition member having a substantially bottomed cylindrical partition wall disposed between the rotor and the stator; a flat circuit board fixed to the partition wall in the axial direction of the rotor, the flat circuit board being located outside the partition wall; and a resin sealing member covering the stator and the circuit board, wherein when a direction in which the circuit board is arranged with respect to the partition wall in the axial direction is a first direction, a direction opposite to the first direction is a second direction, a predetermined direction orthogonal to the axial direction is a front-rear direction, and one of the front-rear directions is a front direction, the stator includes an insulating member and a stator core, the stator core includes a plurality of salient pole portions around which a driving coil is wound via the insulating member, the circuit board is arranged at a position closer to the first direction side than the stator core in a state where a thickness direction and the axial direction of the circuit board are aligned, the insulating member includes a wall portion standing from the stator core toward the first direction side, a gate mark is formed at a front end of an outer peripheral surface of the resin sealing member, the wall portion is arranged at the front end of the stator, and an end surface of the wall portion on the first direction side is in contact with a surface of the circuit board on the second direction side, the circuit board is fixed to the wall portion.

In the pump device of the present invention, the gate mark is formed at the front end of the outer peripheral surface of the resin seal member, and when the resin seal member is formed, the resin material is injected into the mold from the front side, but the wall portion standing from the stator core toward the first direction side is disposed at the front end portion of the stator. In the present invention, the end surface of the wall portion on the first direction side is in contact with the surface of the circuit board on the second direction side, and the circuit board is fixed to the wall portion. Therefore, in the present invention, the resin material injected into the mold from the front side of the stator easily flows toward the outer peripheral side of the stator and the first direction side of the circuit board after colliding with the wall portion.

That is, in the present invention, the resin material injected into the mold from the front side of the stator is less likely to flow directly into the second direction side of the circuit board after colliding with the wall portion. Therefore, in the present invention, even when the injection pressure of the resin material injected into the mold is increased when the resin sealing member is formed, the resin material injected into the mold from the front side of the stator can be prevented from entering the second direction side of the circuit board first after the resin material starts to be injected into the mold. As a result, in the present invention, even if the injection pressure of the resin material injected into the mold is increased when forming the resin sealing member, the circuit board can be prevented from warping toward the first direction side.

In the present invention, the end surface of the first direction side of the wall portion is in contact with the surface of the second direction side of the circuit board, and the circuit board is fixed to the partition wall disposed on the second direction side of the circuit board, so that even when the resin material injected into the mold from the front side of the stator first flows into the first direction side of the circuit board after colliding with the wall portion after the resin material starts to be injected into the mold, warping of the circuit board to the second direction side can be suppressed. As described above, according to the present invention, even when the injection pressure of the resin material injected into the mold is increased when the resin sealing member is formed, the warpage of the circuit board in the first direction and the warpage of the circuit board in the second direction can be suppressed. That is, in the present invention, even if the injection pressure of the resin material injected into the mold is increased when forming the resin sealing member, the warpage of the circuit board can be suppressed.

In the present invention, it is preferable that the insulating member includes a welding portion which is connected to an end surface of the wall portion on the first direction side and which contacts the circuit board from the first direction side. With such a configuration, the circuit board can be reliably fixed to the wall portion with a relatively simple structure.

In the present invention, it is preferable that the pump device includes a detection element for detecting a rotation angle of the rotor based on a magnetic force of the drive magnet, the circuit board is formed with a through hole in which the detection element is disposed, the surface of the circuit board on the first direction side is formed with a pad to which a terminal of the detection element is soldered, and the detection element is disposed on the front side of the center of the circuit board in the front-rear direction.

In the case of such a configuration, when the resin sealing member is formed, the resin material is injected into the mold from the front side of the stator, and then the resin material is injected into the mold from the front side of the stator and collides with the wall portion, and then the resin material first flows into the first direction side of the circuit board, so that the surface of the detection element on the first direction side is covered first, and then the surface of the detection element on the second direction side is covered. Therefore, even if the detection element is disposed in the through hole of the circuit board, the detection element can be prevented from floating from the land formed on the surface of the circuit board on the first direction side.

In the present invention, it is preferable that the pump device includes a detection element for detecting a rotation angle of the rotor based on a magnetic force of the driving magnet, the circuit board is formed with a through hole in which the detection element is disposed, the circuit board is formed with a pad on a surface on a first direction side thereof, the pad being soldered to a terminal of the detection element, and the wall portion is disposed on a front side of the detection element when viewed from the first direction side.

In the case of such a configuration, when the resin sealing member is formed, the resin material is injected into the mold from the front side of the stator, and then the resin material that has first flowed into the first direction side of the circuit board after the resin material has been injected into the mold from the front side of the stator and has collided with the wall portion can first cover the surface of the detection element on the first direction side and then cover the surface of the detection element on the second direction side. Therefore, even if the detection element is disposed in the through hole of the circuit board, the detection element can be prevented from floating from the land formed on the surface of the circuit board on the first direction side.

(effects of utility model)

As described above, in the pump device including the resin sealing member covering the stator and the circuit board, even when the injection pressure of the resin material injected into the mold is increased when the resin sealing member is formed, the warpage of the circuit board can be suppressed.

Drawings

Fig. 1 is a sectional view of a pump device according to an embodiment of the present invention.

Fig. 2 is a perspective view of the pump device shown in fig. 1 with the impeller, the rotor, and the upper case removed.

Fig. 3 is a perspective view of the circuit board, the stator, and the partition member shown in fig. 1.

Fig. 4 is a bottom view of the circuit board, the stator, and the partition member shown in fig. 3.

Fig. 5 is a bottom view of the stator shown in fig. 3.

Description of the reference numerals

1 … pump device; 2 … impeller; 4 … circuit substrate; 4a … through holes; 4b … pad; 5 … rotor; 6 … stator; 11 … partition wall members; 11a … partition wall; 12 … resin sealing member; 12a … gate vestige; 14 … a driving magnet; 23 … driving coil; 24 … stator core; 24b … salient pole portions; 25 … an insulator; 25a … wall portion; 25f … weld; 28 … Hall element; y … front-to-back; y1 … front direction; z … axial; a Z1 … second direction; z2 … first direction.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

(integral construction of Pump device)

Fig. 1 is a sectional view of a pump device 1 according to an embodiment of the present invention. In the following description, the Z direction in fig. 1 and the like is referred to as the "up-down direction", one of the up-down directions, that is, the Z1 direction in fig. 1 and the like is referred to as the "up direction", and the opposite direction to the up direction, that is, the Z2 direction in fig. 1 and the like is referred to as the "down direction".

The pump device 1 of the present embodiment is a centrifugal pump of a type called a canned pump (canned motor pump), and includes an impeller 2, a motor 3 for rotating the impeller 2, and a circuit board 4 for controlling the motor 3. The motor 3 includes a rotor 5 and a stator 6. The motor 3 of the present embodiment is a three-phase brushless motor. The impeller 2, the motor 3, and the circuit board 4 are disposed inside a casing including a case 7 and an upper case 8 covering an upper portion of the case 7. The housing 7 and the upper case 8 are fixed to each other by screws not shown.

The upper case 8 is formed with a fluid suction portion 8a and a fluid discharge portion 8 b. A pump chamber 9 through which the fluid sucked from the suction portion 8a passes toward the discharge portion 8b is formed between the outer casing 7 and the upper casing 8. Further, a seal member (O-ring) 10 for ensuring the sealing property of the pump chamber 9 is disposed at the joint portion between the housing 7 and the upper housing 8. The housing 7 includes a partition member 11 and a resin sealing member 12, the partition member 11 having a partition wall 11a disposed between the pump chamber 9 and the stator 6 so as to partition the pump chamber 9 and the stator 6, the resin sealing member 12 covering a lower surface and a side surface of the partition member 11.

The rotor 5 includes a driving magnet 14, a cylindrical sleeve 15, and a holding member 16 for holding the driving magnet 14 and the sleeve 15. The holding member 16 is formed in a substantially cylindrical shape with a flange. The driving magnet 14 is fixed to the outer peripheral side of the holding member 16, and the sleeve 15 is fixed to the inner peripheral side of the holding member 16. The impeller 2 is fixed to the flange portion 16a of the holding member 16 disposed on the upper side. That is, the impeller 2 is attached to the rotor 5. The impeller 2 and the rotor 5 are disposed in the pump chamber 9. In the following description, the radial direction of the rotor 5 is referred to as the "radial direction", and the circumferential direction (circumferential direction) of the rotor 5 is referred to as the "circumferential direction".

The rotor 5 is rotatably supported by a fixed shaft 17. The fixed shaft 17 is disposed so that the axial direction of the fixed shaft 17 coincides with the vertical direction. That is, the vertical direction is the axial direction of the rotor 5. The upper end of the fixed shaft 17 is held by the upper case 8, and the lower end of the fixed shaft 17 is held by the housing 7. The fixed shaft 17 is inserted through the inner peripheral side of the sleeve 15. Further, a thrust bearing member 18 is attached to the fixed shaft 17 so as to abut on the upper end surface of the sleeve 15. In the present embodiment, the sleeve 15 functions as a radial bearing of the rotor 5, and the sleeve 15 and the thrust bearing member 18 function as a thrust bearing of the rotor 5.

The sleeve 15 is a resin bearing formed of resin. The sleeve 15 is formed by resin molding using a mold. The inner diameter of the sleeve 15 is constant. An annular flange portion 15a spreading radially outward is formed on the upper end side of the sleeve 15. The flange portion 15a functions to prevent the sleeve 15 from coming off (specifically, coming off in the vertical direction) from the holding member 16. A flat portion for preventing rotation of the sleeve 15 with respect to the holding member 16 is formed in a part of the outer peripheral surface of the flange portion 15 a. A gate mark (not shown) is formed on the flat surface portion, and the gate mark is a mark of a gate of a mold used for forming the sleeve 15. In the present embodiment, in manufacturing the sleeve 15, after resin molding, post-processing (machining) of the inner peripheral surface of the sleeve 15 is not performed.

When the sleeve 15 is molded, a columnar pin constituting a part of the mold is disposed on the inner peripheral side of the sleeve 15, and after molding, the pin is pulled out toward the upper end side of the sleeve 15. The outer diameter of the portion of the pin forming the inner peripheral surface of the lower end portion of the sleeve 15 is slightly larger than the outer diameter of the other portion of the pin. That is, the outer diameter of the end portion on the side away from the gate, of the two end portions of the pin, is slightly larger than the outer diameter of the other portion of the pin. For example, the outer diameter of the end of the pin on the side away from the gate is about 0.02(mm) larger than the outer diameter of the other part of the pin. In the present embodiment, since the outer diameter of the end portion of the pin on the side away from the gate is slightly larger than the outer diameter of the other portion of the pin, the inner diameter of the sleeve 15 after molding is constant.

The stator 6 includes a driving coil 23, a stator core 24, and an insulator 25 serving as an insulating member, and is formed in a cylindrical shape as a whole. Specifically, the stator 6 is formed in a substantially cylindrical shape. The stator 6 is disposed on the outer peripheral side of the rotor 5 with a partition wall 11a interposed therebetween. The stator 6 is disposed so that the axial direction of the stator 6 coincides with the vertical direction. The specific structure of the stator 6 will be described later.

The partition member 11 is formed of an insulating resin material. As described above, the partition member 11 includes the partition wall 11 a. The partition wall 11a is formed into a substantially bottomed cylindrical shape with a flange, and includes a cylindrical portion 11b, a bottom portion 11c, and a flange portion 11 d. The cylindrical portion 11b is formed in a cylindrical shape and covers the outer peripheral surface of the driving magnet 14. The cylindrical portion 11b is disposed radially between the rotor 5 and the stator 6. That is, the partition wall 11a is disposed between the rotor 5 and the stator 6.

The bottom portion 11c is formed in a disc shape that closes the lower end of the cylindrical portion 11 b. The flange portion 11d is formed to expand radially outward from the upper end of the cylindrical portion 11 b. As shown in fig. 1, the inside and the upper side of the partition wall 11a form the pump chamber 9, and the impeller 2 and the rotor 5 are disposed inside and above the partition wall 11 a. The partition wall 11a functions to prevent the fluid in the pump chamber 9 from flowing into the stator 6 and the circuit board 4.

A shaft holding portion 11g (see fig. 1) for holding the lower end of the fixed shaft 17 is formed on the upper surface of the bottom portion 11 c. The shaft holding portion 11g protrudes upward from the upper surface of the bottom portion 11 c. On the lower surface of the bottom portion 11c, a fixing protrusion 11e for fixing the circuit board 4 to the partition wall 11a and a positioning protrusion 11f for positioning the circuit board 4 are formed. The fixing projection 11e and the positioning projection 11f project downward from the lower surface of the bottom portion 11 c.

The circuit board 4 is a rigid board such as a glass epoxy board, and is formed in a flat plate shape. The circuit board 4 is fixed to the partition wall 11a in a state where the thickness direction of the circuit board 4 is aligned with the vertical direction. The circuit board 4 is fixed to the lower end portion of the partition wall 11 a. Specifically, the circuit board 4 is fixed by the screws 27 screwed into the fixing protrusions 11e in a state of being positioned by the fixing protrusions 11e and the positioning protrusions 11f, and the circuit board 4 is fixed to the bottom portion 11c at a position lower than the bottom portion 11 c.

That is, the circuit board 4 is fixed to the partition wall 11a outside the partition wall 11a in the vertical direction and is disposed outside the pump chamber 9. The circuit board 4 is disposed below the driving coil 23 and the stator core 24. The lower direction (Z2 direction) in the present embodiment is a first direction that is a direction in which the circuit board 4 is arranged with respect to the partition wall 11a in the axial direction of the rotor 5, and the upper direction (Z1 direction) is a second direction that is a direction opposite to the first direction. The specific structure of the circuit substrate 4 will be described later.

The resin sealing member 12 is formed of BMC (Bulk Molding Compound). The resin sealing member 12 covers the stator 6 and the circuit board 4. The resin sealing member 12 serves to protect the circuit board 4, the driving coil 23, and the like from the fluid. The resin sealing member 12 is formed in a substantially bottomed cylindrical shape as a whole, and completely covers the stator 6, the cylindrical portion 11b, and the bottom portion 11 c. The resin sealing member 12 covers substantially the entire lower surfaces of the circuit board 4 and the flange 11 d. The specific structure of the resin sealing member 12 will be described later.

(Structure of stator, Circuit Board and resin sealing Member)

Fig. 2 is a perspective view of the pump device 1 shown in fig. 1 in a state in which the impeller 2, the rotor 5, and the upper case 8 are removed. Fig. 3 is a perspective view of the circuit board 4, the stator 6, and the partition member 11 shown in fig. 1. Fig. 4 is a bottom view of the circuit board 4, the stator 6, and the partition member 11 shown in fig. 3. Fig. 5 is a bottom view of the stator 6 shown in fig. 3.

In the following description, a predetermined direction orthogonal to the vertical direction (axial direction of the rotor 5), that is, the Y direction in fig. 1 and the like is referred to as the "front-rear direction", and the X direction in fig. 1 and the like orthogonal to the vertical direction and the front-rear direction is referred to as the "left-right direction". In addition, one of the front-rear directions, i.e., the Y1 direction in fig. 1 and the like, is referred to as a "front direction", and the opposite direction to the front direction, i.e., the Y2 direction in fig. 1 and the like, is referred to as a "rear direction".

As described above, the stator 6 includes the driving coil 23, the stator core 24, and the insulator 25. The stator core 24 is a laminated core formed by laminating thin magnetic plates made of a magnetic material. The stator core 24 includes an outer circumferential ring 24a formed in an annular shape and a plurality of salient pole portions 24b protruding radially inward from the outer circumferential ring 24 a. The stator core 24 of the present embodiment includes nine salient pole portions 24 b. The number of the salient pole portions 24b of the stator core 24 may be other than nine.

The outer peripheral ring portion 24a is formed in a ring shape having a substantially circular outer peripheral surface when viewed in the vertical direction. The outer peripheral surface of the outer peripheral ring portion 24a constitutes the outer peripheral surface of the stator core 24. The salient pole tip portion constituting the tip end portion of the salient pole portion 24b faces the outer peripheral surface of the driving magnet 14 through the cylindrical portion 11 b. The shape of the tip of the projecting electrode is an arc shape when viewed from the top-bottom direction. The stator core 24 of the present embodiment is a so-called curled core, and is formed in a ring shape by connecting end portions of a core including a strip-shaped core and nine salient pole portions 24b standing from one surface of the strip-shaped core. The stator core 24 may be a so-called split core formed by combining a plurality of cores divided in the circumferential direction.

The insulator 25 is formed of a resin material having insulating properties. In the present embodiment, the insulator 25 is constituted by a plurality of individual insulators 26 mounted on each of the projecting pole portions 24 b. That is, the insulator 25 is constituted by nine independent insulators 26 formed separately. The independent insulator 26 is formed into a flanged cylindrical shape having flange portions at both ends, and is attached to the salient pole portion 24b so that the axial direction of the cylindrical independent insulator 26 coincides with the radial direction of the stator 6. The independent insulator 26 includes an outer flange portion 26a constituting an outer portion of the independent insulator 26 in the radial direction. The outer flange 26a covers both upper and lower end surfaces of a part of the outer peripheral ring portion 24a and an inner peripheral side of a part of the outer peripheral ring portion 24 a.

Flat plate-

like projections

25a, 25b, and 25c projecting downward are formed on the lower end side of the insulator 25. The

projections

25a, 25b, 25c are formed on the outer side portion of the insulator 25 in the radial direction. The thickness direction of the

projections

25a, 25b, 25c formed in a flat plate shape coincides with the radial direction. The protruding portions 25a are formed at two positions of the front end portion of the insulator 25, the protruding portion 25b is formed at one position of the right end portion of the insulator 25 and one position of the left end portion of the insulator 25, and the protruding portion 25c is formed at one position of the rear end portion of the insulator 25. That is, the protruding portion 25a is disposed at the front end portion of the stator 6, the protruding portions 25b are disposed at both left and right end portions of the stator 6, and the protruding portion 25c is disposed at the rear end portion of the stator 6.

The protruding

portions

25a, 25b, and 25c are formed on the outer flange portion 26a of the independent insulator 26, and cover a lower end surface of a part of the outer peripheral ring portion 24a of the stator core 24. The two protrusions 25a are formed on outer flange portions 26a of two independent insulators 26 disposed on the front end side of the insulator 25, respectively. The protruding

portions

25a, 25b, and 25c stand downward from the stator core 24. Specifically, the

projections

25a, 25b, and 25c stand downward from the lower end surface of the outer peripheral ring portion 24 a. The lower end surfaces of the

projections

25a, 25b, and 25c are planes perpendicular to the vertical direction. The lower end surfaces of the protruding

portions

25a, 25b, and 25c contact the upper surface of the circuit board 4.

The protruding portion 25a of the present embodiment is a wall portion that is arranged at the front end of the stator 6 while standing downward from the stator core 24. Therefore, in the following description, the protrusion 25a is referred to as a "wall 25 a". The wall portion 25a is disposed at the center of the stator 6 in the left-right direction. The outer surface of the wall portion 25a in the radial direction is arranged radially outward of the end surface (outer peripheral surface) of the circuit board 4.

A projection 25e projecting downward is formed on the lower end surface of the wall portion 25 a. The tip (lower end) of the protrusion 25e is a soldering portion 25f (see fig. 4) which is in contact with the circuit board 4 from below. That is, the insulator 25 includes a soldering portion 25f which is in contact with the circuit board 4 from below, and the soldering portion 25f is connected to the lower end surface of the wall portion 25 a. The circuit board 4 is fixed to the wall portion 25a by a soldering portion 25 f. Fig. 3 and 5 show the projection 25e before the welded portion 25f is formed.

Similarly, a projection 25g projecting downward is formed on the lower end surface of the projection 25 b. The tip (lower end) of the protrusion 25g is a soldering portion 25h (see fig. 4) which is in contact with the circuit board 4 from below. That is, the insulator 25 includes a soldering portion 25h which is in contact with the circuit board 4 from below, and the soldering portion 25h is connected to the lower end surface of the projection 25 b. The circuit board 4 is fixed to the protruding portion 25b by a soldering portion 25 h. Fig. 3 and 5 show the projection 25g before the welded portion 25h is formed. No projection is formed on the lower end surface of the projection 25 c.

The driving coil 23 is formed of a lead wire 23a (see fig. 3 and 4) made of copper alloy or the like. The driving coil 23 is wound around each of the nine salient pole portions 24b via an insulator 25, and the stator 6 includes nine driving coils 23. As described above, the motor 3 of the present embodiment is a three-phase brushless motor, three driving coils 23 of the nine driving coils 23 are U-phase coils, three driving coils 23 of the remaining six driving coils 23 are V-phase coils, and the remaining three driving coils 23 are W-phase coils.

The U-phase coil, the V-phase coil, and the W-phase coil are arranged in order in the circumferential direction. Three U-phase coils are formed by winding one lead wire 23a in order around three salient pole portions 24b, three V-phase coils are formed by winding one lead wire 23a in order around three salient pole portions 24b, and three W-phase coils are formed by winding one lead wire 23a in order around three salient pole portions 24 b.

A detection element 28 for detecting the rotation angle of the rotor 5 based on the magnetic force of the driving magnet 14 is mounted on the circuit board 4. The detection element 28 of the present embodiment is a hall element. Therefore, the detection element 28 is hereinafter referred to as "hall element 28". The hall element 28 is a surface-mount hall element. The motor 3 of the present embodiment is a three-phase motor, and three hall elements 28 are mounted on the circuit board 4. In fig. 1, the hall element 28 is not shown.

The circuit board 4 is formed with a through hole 4a in which the hall element 28 is disposed. The through hole 4a penetrates the circuit board 4 in the vertical direction. The upper surface of the hall element 28 as a detection surface (magnetic induction surface) is disposed above the upper surface of the circuit board 4. The upper surface of the hall element 28 faces the lower end surface of the driving magnet 14 through the bottom portion 11 c. A land 4b (see fig. 4) to which a terminal of the hall element 28 is soldered is formed on the lower surface of the circuit board 4. The lower surface of the hall element 28 is disposed slightly below the lower surface of the circuit board 4.

The three hall elements 28 are arranged concentrically with respect to the rotation center of the rotor 5 (i.e., the axial center of the fixed shaft 17) when viewed from the lower side. The three hall elements 28 are arranged on the front side of the center of the circuit board 4 in the front-rear direction. The three hall elements 28 are disposed behind the two wall portions 25a when viewed from the lower side, and are disposed at substantially the same positions as the two wall portions 25a in the left-right direction. That is, the wall portion 25a is disposed on the front side of the three hall elements 28 when viewed from the lower side.

The outer peripheral end of the circuit board 4 is formed with a notch in which the upper end portions of the

projections

25e and 25g are arranged. The

soldering portions

25f and 25h contact the lower surface of the circuit board 4. Further, a notch is formed at the outer peripheral end of the circuit board 4, in which the end of the lead 23a is disposed. The pad 4c at the end of the solder wire 23a is formed on the lower surface of the circuit board 4 along the edge of the notch. The pad 4c is formed at three locations.

The rear end of the circuit board 4 is a lead connection portion 4d for soldering and fixing an end of a lead 29 (see fig. 1) drawn out from the circuit board 4. Further, a transistor 30 for driving and controlling the motor 3, an IC (Integrated Circuit) 31, and a regulator 32 are mounted on the lower surface of the Circuit board 4. In fig. 1, the transistor 30, the IC31, and the regulator 32 are not shown.

As described above, the resin sealing member 12 completely covers the stator 6, the cylindrical portion 11b, and the bottom portion 11 c. As described above, the resin sealing member 12 covers substantially the entire lower surfaces of the circuit board 4 and the flange 11 d. Specifically, the resin sealing member 12 covers all portions of the circuit board 4 except the lead connecting portion 4d and the lower surface of the flange portion 11 d. A holding member 33 (see fig. 1) for holding the lead 29 is fixed to the rear end portion of the resin sealing member 12.

In the present embodiment, after the insulator 25 is attached to the strip core before the stator core 24 formed in a ring shape, the driving coil 23 is wound, and thereafter, the ends of the strip core are connected to each other to form the stator core 24 formed in a ring shape. When the stator 6 is completed by forming the annular stator core 24, the cylindrical portion 11b of the partition member 11 is inserted into the inner circumferential side of the stator 6, and the stator 6 is mounted on the partition member 11. After that, in a state where the circuit substrate 4 has been positioned by the fixing protrusions 11e and the positioning protrusions 11f, the circuit substrate 4 is fixed to the partition member 11 by the screws 27 screwed into the fixing protrusions 11 e.

Thereafter, the distal ends of the

projections

25e and 25g of the insulator 25 are melted to form the welded

portions

25f and 25 h. Thereafter, the end of the lead wire 23a is soldered to the pad 4 c. Thereafter, the partition member 11 to which the circuit board 4 and the stator 6 are fixed is placed in a mold, and a resin material is injected into the mold and cured to form the resin sealing member 12. That is, the resin sealing member 12 is formed by injection molding a resin material to the partition member 11 in a state where the circuit board 4 and the stator 6 are fixed.

In the present embodiment, when the resin sealing member 12 is formed by injection molding, a resin material is injected into a mold from the front side. Therefore, a gate mark 12a (see fig. 2) which is a mark of an inlet (gate) of the resin when the resin sealing member 12 is formed at the front end of the outer peripheral surface of the resin sealing member 12. The gate mark 12a is formed at the center position of the resin sealing member 12 in the left-right direction. The gate mark 12a is formed in a rectangular shape elongated in the vertical direction. The lower end of the gate mark 12a is disposed below the lower surface of the circuit board 4, and the upper end of the gate mark 12a is disposed above the lower end surface of the stator core 24. When the resin sealing member 12 is molded, the rear end portion of the circuit board 4 (i.e., the lead connecting portion 4d) and the rear end portion of the partition member 11, which are disposed in the mold, are supported by the mold.

(main effect of the present embodiment)

As described above, in the present embodiment, the gate mark 12a is formed at the front end of the outer peripheral surface of the resin sealing member 12, and when the resin sealing member 12 is formed, the resin material is injected into the mold from the front side, and the wall portion 25a standing downward from the stator core 24 is disposed at the front end portion of the stator 6. In the present embodiment, the lower end surface of the wall portion 25a is in contact with the upper surface of the circuit board 4, and the circuit board 4 is fixed to the wall portion 25 a. Therefore, in the present embodiment, the resin material injected into the mold from the front side of the stator 6 easily flows toward the outer peripheral side of the stator 6 and the lower side of the circuit board 4 after colliding with the wall portion 25 a.

That is, in the present embodiment, the resin material injected into the mold from the front side of the stator 6 is less likely to flow directly above the circuit board 4 after colliding with the wall portion 25 a. Therefore, in the present embodiment, even if the injection pressure of the resin material injected into the mold is increased when the resin sealing member 12 is formed, the resin material injected into the mold from the front side of the stator 6 can be suppressed from entering the upper side of the circuit board 4 at the earliest stage after the resin material injection into the mold is started. As a result, in the present embodiment, even if the injection pressure of the resin material injected into the mold is increased when forming the resin sealing member 12, the circuit board 4 can be prevented from warping downward.

In the present embodiment, the lower end surface of the wall portion 25a is in contact with the upper surface of the circuit board 4, and the circuit board 4 is fixed to the partition wall 11a disposed above the circuit board 4, so that even when the resin material injected into the mold from the front side of the stator 6 collides with the wall portion 25a and first flows below the circuit board 4 after the resin material starts to be injected into the mold, the resin material can be prevented from warping upward of the circuit board 4. In particular, in the present embodiment, since the lower end surfaces of the protruding

portions

25b and 25c are also in contact with the upper surface of the circuit board 4, even if the resin material injected into the mold from the front side of the stator 6 first flows to the lower side of the circuit board 4 after the resin material is injected into the mold, the resin material collides with the wall portion 25a, and then the resin material is effectively prevented from warping upward of the circuit board 4.

As described above, in the present embodiment, even if the injection pressure of the resin material injected into the mold is increased when forming the resin sealing member 12, the warpage of the circuit board 4 toward the lower side and the warpage of the circuit board 4 toward the upper side can be suppressed. That is, in the present embodiment, even if the injection pressure of the resin material injected into the mold is increased when forming the resin sealing member 12, the warpage of the circuit board 4 can be suppressed.

In the present embodiment, the insulator 25 includes a soldering portion 25f that contacts the circuit board 4 from below, and the soldering portion 25f is connected to the lower end surface of the wall portion 25 a. Therefore, in the present embodiment, the circuit substrate 4 can be reliably fixed to the wall portion 25a with a relatively simple structure. In the present embodiment, the insulator 25 includes the soldering portion 25h that contacts the circuit board 4 from below, and the soldering portion 25h is connected to the lower end surface of the projection 25 b. Therefore, in the present embodiment, the circuit substrate 4 can be reliably fixed to the protruding portion 25b with a relatively simple structure.

In the present embodiment, the hall element 28 is disposed on the front side of the center of the circuit board 4 in the front-rear direction. In the present embodiment, the wall portion 25a is disposed on the front side of the hall element 28 when viewed from the lower side. Therefore, in the present embodiment, after the resin material starts to be injected into the mold, the resin material injected into the mold from the front side of the stator 6 collides with the wall portion 25a and first flows into the lower side of the circuit board 4, thereby first covering the lower surface of the hall element 28 and then covering the upper surface of the hall element 28. Therefore, in the present embodiment, even if the hall element 28 is disposed in the through hole 4a of the circuit board 4, the hall element 28 can be prevented from floating from the land 4b formed on the lower surface of the circuit board 4.

(other embodiments)

The above embodiment is an example of the preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without changing the gist of the present invention.

In the above embodiment, the three hall elements 28 and the two wall portions 25a may be arranged at positions shifted in the left-right direction. In the above embodiment, the three hall elements 28 may be disposed on the rear side of the center of the circuit board 4 in the front-rear direction. In the above embodiment, the detection element for detecting the rotation angle of the rotor 5 based on the magnetic force of the driving magnet 14 may be a magnetic detection element other than the hall element 28.

In the above embodiment, the circuit board 4 is fixed to the wall portion 25a by soldering using the soldering portion 25f, but for example, the circuit board 4 may be fixed to the wall portion 25a by snap-fitting using elastic deformation of the wall portion 25a and the projection 25e, or the circuit board 4 may be fixed to the wall portion 25a by screws. Similarly, for example, the circuit board 4 may be fixed to the projection 25b by a snap using elastic deformation of the projection 25b and the projection 25g, and the circuit board 4 may be fixed to the projection 25b by a screw.

In the above embodiment, the nine independent insulators 26 are formed separately, but the nine independent insulators 26 may be formed integrally. In the above embodiment, after the driving coil 23 is wound around the bobbin formed in a flanged cylindrical shape, the bobbin around which the driving coil 23 is wound may be attached to the salient pole portion 24b of the stator core 24. In this case, a wall portion corresponding to the wall portion 25a is formed on the bobbin. In this case, the insulating member corresponding to the insulator 25 is constituted by a plurality of bobbins.

In the above embodiment, two wall portions 25a are arranged at the distal end portion of the stator 6, but three or more wall portions 25a may be arranged at the distal end portion of the stator 6, or one wall portion 25a may be arranged at the distal end portion of the stator 6. In the above embodiment, the impeller 2 may be formed integrally with the rotor 5. For example, the impeller 2 may be formed integrally with the holding member 16.

Claims

1. A pump device is characterized by comprising:

an impeller;

a rotor having the impeller mounted thereon and having a driving magnet;

a stator formed in a cylindrical shape, disposed on an outer peripheral side of the rotor, and having a driving coil;

a partition member having a bottomed cylindrical partition wall disposed between the rotor and the stator;

a flat circuit board fixed to the partition wall on an outer side of the partition wall in the axial direction of the rotor; and

a resin sealing member made of resin and covering the stator and the circuit board,

when a direction in which the circuit board is arranged with respect to the partition wall in the axial direction is a first direction, a direction opposite to the first direction is a second direction, a predetermined direction orthogonal to the axial direction is a front-rear direction, and one of the front-rear directions is a front direction,

the stator includes an insulating member and a stator core having a plurality of salient pole portions around which the driving coil is wound via the insulating member,

the circuit board is disposed on a first direction side of the stator core in a state where a thickness direction of the circuit board and the axial direction are aligned,

the insulating member includes a wall portion standing from the stator core toward a first direction side,

a gate mark is formed at the front end of the outer peripheral surface of the resin sealing member,

the wall portion is disposed at a front end portion of the stator,

an end surface of the wall portion on the first direction side is in contact with a surface of the circuit substrate on the second direction side,

the circuit board is fixed to the wall portion.

2. Pump apparatus according to claim 1,

the insulating member includes a soldering portion connected to an end surface of the wall portion on the first direction side and contacting the circuit board from the first direction side.

3. Pump arrangement according to claim 1 or 2,

a detection element for detecting the rotation angle of the rotor based on the magnetic force of the driving magnet,

a through hole for disposing the detection element is formed in the circuit board,

a land on which a terminal of the detection element is soldered is formed on a surface of the circuit board on the first direction side,

the detection element is disposed on the front side of the center of the circuit board in the front-rear direction.

4. Pump arrangement according to claim 1 or 2,

the wall portion is disposed on a front side of the detection element when viewed from the first direction side.

5. Pump arrangement according to claim 1 or 2,

the wall portion is disposed on a front side of the detection element when viewed from the first direction side,