JP2009127570A - Electric water pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric water pump capable of releasing heat generated by a stator core and a winding during operation by cooling water, and of reducing heat transfer to a circuit board while maintaining waterproofness of a connection terminal of a stator core. <P>SOLUTION: This pump includes a pump housing 1, the stator core 4 having the winding 5 wound thereon, a core coating part 71 resin-coating the stator core 4, the connection terminal 6 exposed from the core coating part 71, a connection terminal coated part 71 resin-coating the connection terminal 6, and the circuit board 8 controlling current to the winding 5. The core coated part 71 and the connection terminal coated part 72 are disposed in a cooling water flowing zone Sa in the pump housing 1. The circuit board 8 is disposed in a cooling water non-flowing zone Sb. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric water pump capable of releasing heat generated by a stator core and a winding during operation by cooling water, maintaining a waterproof property of a connection terminal of the stator core, and reducing heat conduction to a circuit board. .

  As an electric water pump for automobiles, an electromagnet as a stator is arranged on the outer peripheral side of a partition wall in a pump housing, and a motor is constituted by an impeller incorporating a magnet as an inner rotor, and the impeller is rotated along with the rotation of the inner rotor In recent years, an integrated electric water pump in which a motor portion of a rotating type and a pump portion are integrated has been adopted. Patent document 1 is mentioned as an example of such an integrated electric water pump.

  In Patent Document 1, a stator (electromagnet) is provided on the outer peripheral side of the partition wall, and an impeller incorporating a magnet as an inner rotor is disposed on the inner peripheral side of the partition wall. Then, the impeller is rotated by the magnetic attraction and repulsion action between the stator and the inner rotor, and the cooling water is transported as indicated by reference numeral “F” in FIG.

In the case of an integrated electric water pump as seen in Patent Document 1, the direction of the current of the winding wound around the stator is controlled / changed by the relative angle (phase) relationship between the stator and impeller magnets, and the impeller is It keeps rotating. In order to perform such control, a control circuit is integrated in the pump.
JP 2006-299975

  In an integrated electric water pump, there is a stator core for rotating a rotor provided with an impeller and a magnet. This stator core is usually provided by a resin insulator for insulating the laminated steel plates. The coil is energized to operate the pump, but if the heat generated by the coil is not transmitted to the surroundings or if the drive time is long, the heat generated from the coil is large. As a result, the electrical resistance of the winding increases.

  For this reason, when the amount of heat generated from the winding wound around the stator core is large, the temperature of the winding itself increases. This temperature rise may cause trouble in the control system, and the efficiency may decrease due to an increase in the electric resistance value. Specifically, since heat is transmitted to the control circuit board mounted near the stator core in the pump housing, the temperature of the elements on the board also rises. In addition, an increase in electrical resistance due to the winding of the stator core may reduce the current, thereby reducing the efficiency, and increasing the temperature of the element on the substrate may reduce the life of the element on the circuit board.

  From the above, how to cool the heat generation of the stator core winding has been a long-standing problem. The above-mentioned patent document 1 exists in what was proposed as a solution of such a subject. In Patent Document 1, a stator core is molded with resin, and water channels are provided on both end surfaces and outer peripheral surfaces in the axial direction of the molded stator core, and the stator core is directly cooled by cooling water. By this patent document 1, most of the heat generated from the winding of the stator core can be directly released to the cooling water.

  However, Patent Document 1 has the following problems. That is, since it is necessary to supply electric power to the winding itself, there is always a connection terminal portion between the winding and the circuit board. The stator core itself is water-tightly coated and cooled using cooling water flowing through the pump housing, but the surface including the connection terminal portion is separated from the pump cooling water so as to be separated from the pump cooling water. It is connected to the. Since the connection terminal portion cannot be brought into direct contact with the cooling water, it is impossible to bring all the surfaces outside the stator core into contact with the cooling water.

  Specifically, as disclosed in FIG. 1 of Patent Document 1, the inner peripheral side of the stator core 26 and the inner peripheral part of the circuit side cannot be brought into contact with cooling water because of the support and wiring of the stator core 26. For this reason, when heat conduction is performed through a connection terminal that supplies power to the winding, no means for cooling the connection terminal is provided, and the heat of the winding is connected to the circuit through the connection terminal. There is a risk that the life of the elements of the circuit board may be reduced due to heat conduction to the board.

  As described above, since the positive cooling structure of the connection terminal is not provided, the heat conduction through the connection terminal is increased, and when the operating current is increased, the heat conduction is further increased and the life of the element of the electronic circuit is increased. May decrease. For this reason, the output of the motor cannot be increased. Furthermore, there are various problems such as a reduction in motor efficiency due to an increase in the electrical resistance value of the windings of the stator core due to heat generation. An object (technical problem) of the present invention is that heat generated in the winding is transmitted to the circuit board through the stator core or the pump housing, or heat generated in the winding is conducted to the circuit board through the connection terminal. By preventing and more effective cooling, the motor efficiency is improved and the circuit board is protected from heat.

  According to a first aspect of the present invention, there is provided a pump housing, a stator core around which a winding is wound, a core coating portion that resin-coats the stator core, a connection terminal exposed from the core coating portion, and a resin coating the connection terminal. It consists of a connection terminal covering part and a circuit board for controlling the current to the winding, and the core covering part and the connection terminal covering part are installed in a flow area of cooling water in the pump housing, and the circuit board is The electric water pump installed in the non-circulating region of the cooling water solves the above problems.

  According to a second aspect of the present invention, the above-described problem is solved by using the electric water pump in which the core covering portion and the connection terminal covering portion are integrally formed in the above-described configuration. According to a third aspect of the present invention, the above-described problem is solved by employing an electric water pump in which the core covering portion and the connection terminal covering portion are separate members and are connected in a watertight manner in the configuration described above. According to a fourth aspect of the present invention, the above-described problem is solved by employing an electric water pump in which the core covering portion has softness in the above-described configuration.

  According to the invention of claim 1, since the core covering portion and the connection terminal covering portion are installed in the cooling water circulation region in the pump housing, and the circuit board is installed in the non-circulation region of the cooling water, The terminal is structured to be constantly cooled by cooling water when the pump is operated, while maintaining watertightness by the connection terminal covering portion. Therefore, the heat conduction to the circuit board can be reduced by the cooling water, the operating current can be improved, the motor output can be increased, and the reliability can be improved.

  In other words, since the connection terminal is located in the cooling water flow region through the connection terminal covering portion, the connection terminal is actively cooled, and the connection terminal can conduct heat even when the operating current is increased. It can be increased by the cooling water, the number of rotations of the rotor can be increased, and high output and improved reliability can be ensured.

  According to invention of Claim 2, since the said core coating | coated part and the connection terminal coating | coated part are integrally formed, the water-tightness of a core coating | coated part and a connection terminal coating | coated part is favorable, and it uses it in the stable state. be able to. Further, since the core covering portion and the connection terminal covering portion are integrally formed, they are inexpensive. According to the invention of claim 3, since the core cover part and the connection terminal cover part are separate members, the lengths of the connection terminal cover parts are variously arranged, so that various pump housing sizes can be obtained. Can be adapted to. That is, since the mold can be shared even if the size of the pump housing is slightly different, the total cost can be reduced. According to the invention of claim 4, the core covering portion has flexibility, so that it can be flexibly deformed with respect to a change in the flow of cooling water in the circulation region, thereby improving the durability of the connection terminal covering portion. This can be further improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1 (A), the configuration of the present invention mainly includes a pump core 1, a rotor 3, a stator core 4 composed of a laminated steel plate 4a surrounding the periphery of the rotor 3, and an insulator 4b. A winding 5 wound around the stator core 4, a connection terminal 6, a resin coating 7 that covers the stator core 4 and the winding 5, and a circuit board 8 that controls the current of the winding 5 of the stator core 4; Consists mainly of.

  As shown in FIG. 1A, the pump housing 1 including the cover portion 1a and the motor portion 1b includes a pump chamber 11, a rotor chamber 12, and a circuit board storage chamber 13, and the rotor chamber 12 and the circuit board are arranged. The storage chamber 13 is partitioned by a partition wall portion 14. The pump chamber 11 is provided with a suction port 11a and a discharge port 11b. The rotor chamber 12 is a portion in which a rotor 3 and a stator core 4 described later are accommodated. The circuit board storage chamber 13 is a part to which a circuit board 8 described later is mounted.

  The pump chamber 11 and the rotor chamber 12 are chambers through which cooling water flows, and are referred to as a flow region Sa (see FIG. 1). The circuit board storage chamber 13 is a chamber through which no coolant flows, and is referred to as a non-circulation region Sb. As described above, the partition wall portion 14 is a wall that partitions the circuit board housing chamber 13 from the pump chamber 11 and the rotor chamber 12 inside the pump housing 1, and the pump housing 1 includes the partition wall portion 14. Thus, the cooling water is divided into the circulation region Sa and the non-circulation region Sb (see FIG. 1).

  As shown in FIG. 1, the rotor 3 is composed of a magnet rotor portion 31 and an impeller portion 32. The magnet rotor portion 31 is formed in a cylindrical shape, and a rotor rotation support shaft 15 to be described later is inserted into a through hole 31a in the center of the diameter, and is fixed in the axial direction by a fastener such as a retaining ring. The impeller portion 32 includes a blade base 32a and a blade piece 32b, and a plurality of blade pieces 32b are radially provided on the surface of the blade base 32a.

  The rotor rotation support shaft 15 is formed on the partition wall portion 14 of the motor portion 1b of the pump housing 1, and the rotor rotation support shaft 15 has a central position in the diameter direction of the magnet rotor portion 31 and the impeller portion 32. It is installed through. The pump chamber 11 is formed with a bearing portion 16 for supporting the shaft end portion of the rotor rotation support shaft 15, and the shaft end portion of the rotor rotation support shaft 15 is supported by the bearing portion 16 (see FIG. 1). ). Further, the magnet rotor part 31 may be manufactured by a plastic magnet formed in a cylindrical shape.

  The stator core 4 is formed by mounting a winding 5 on a substantially ring-shaped laminated steel plate 4a, and the laminated steel plate 4a includes an outer arc-shaped portion 41 and an inner arc-shaped portion 42, as shown in FIGS. Are connected by the core support portion 43 with an appropriate interval, and the substantially “H” shape is continuous or repeated in plan view (see FIG. 3A). A winding 5 is wound around the core support portion 43 of the laminated steel plate 4a. Specifically, the coil is wound around the core support part 43 many times.

  Thus, the winding 5 is mounted on the laminated steel plate 4a, and the insulator 4b is provided around the winding 5 so as to cover it. And the said winding 5 is connected and the connection terminal 6 for connecting with the circuit board 8 mentioned later is provided so that it may protrude (refer FIG.1 (B), FIG.3 (C)). Specifically, the lead wire 5 a is drawn from a part of the winding 5, and the lead wire 5 a is wound around the connection terminal 6 and connected. The stator core 4 controls the current by a circuit board 8 to be described later, and controls the strength of the magnetic field and magnetic force to rotate the rotor 3. The rotor 3 is mounted such that the magnet rotor portion 31 is rotatable in the rotor chamber 12 by a rotor rotation support shaft 15 formed in the pump housing 1.

  The stator core 4, the winding 5 and the connection terminal 6 are covered with a resin coating 7 as shown in FIGS. 1, 3 (B), (C) and the like. The resin coating 7 is made of a synthetic resin and is composed of a core coating 71 and a connection terminal coating 72. The core covering portion 71 is such that the stator core 4 and the winding 5 are entirely watertight and are housed in a sealed state (see FIG. 4A). Such a core covering portion 71 has a shape that can accommodate the stator core 4 and the winding 5.

  Further, the connecting terminal covering portion 72 covers the connecting terminal 6 exposed from the core covering portion 71 as shown in FIGS. The connection terminal covering portion 72 is formed in a tubular shape (tube shape) and has a structure in which the connection terminal 6 is inserted. The core covering portion 71 and the connection terminal covering portion 72 are integrally formed, and the winding 5 and the connection terminal 6 housed therein are watertightly covered by the core covering portion 71 and the connection terminal covering portion 72. The Specifically, a connection terminal covering portion 72 is formed in the core covering portion 71 where the inner arc-shaped portion 42 of the stator core 4 is located (see FIG. 3).

  Further, as shown in FIG. 5, there is an embodiment in which the core cover portion 71 and the connection terminal cover portion 72 are formed as separate members. Also in this embodiment, the connection terminal covering portion 72 is connected in a watertight manner to the core covering portion 71, and the core covering portion 71 is press-fitted into the inner diameter of the connection terminal covering portion 72. A tubular connecting portion 71a is formed to be connected at. And the tubular connection terminal coating | coated part 72 is connected with the said connection part 71a in the press-fit state, and the core coating | coated part 71 and the connection terminal coating | coated part 72 are connected in a watertight state. Further, there is an embodiment in which the resin coating 7 is formed by embedding the stator core 4 and the winding 5 by resin casting.

  The stator core 4, the winding 5 and the connection terminal 6 covered with a resin coating 7 (core coating portion 71 and connection terminal coating portion 72) in a watertight manner constitute a substantially arc-block electromagnetic body A. The electromagnetic body A substantially constitutes a ring body (see FIG. 3A). In the embodiment of the present invention, the electromagnetic body A has six magnetic poles, but the number of magnetic poles may be eight or ten. The number of magnetic poles is determined by design / experiment.

  The electromagnetic body A is arranged in the rotor chamber 12 of the pump housing 1 as described above. The rotor chamber 12 is a cooling water circulation region Sa, and the electromagnetic body A is cooled by the cooling water. In order for the electromagnetic body A to be effectively cooled by the cooling water, the resin coating 7 is provided in the rotor chamber by the support member 2 so that the cooling water is distributed over substantially the entire surface in the rotor chamber 12. 12 is supported and fixed by a minimum portion (see FIG. 1). The support member 2 is a member interposed between the inner peripheral wall surface of the rotor chamber 12 and the resin cover 7 so that an appropriate water passage for the pump chamber is formed. Moreover, the support member 2 can be made unnecessary by supporting the core covering portion 71 with the cover portion 1 a of the pump chamber 11 and forming a water passage with the core covering portion 71.

  The resin cover 7 of the electromagnetic body A fixed in the rotor chamber 12 is inserted into the connection terminal cover 72 by connecting the connection terminal cover 72 to the communication portion 14 a formed in the partition wall 14. The connection terminal 6 to be connected is connected to the circuit board 8 mounted in the circuit board storage chamber 13 in a watertight state. The communication part 14a is a through-hole formed in the partition wall part 14, and is a stepped hole. An end of the connection terminal covering part 72 and the periphery of the communication part 14a are provided with an O-ring or the like. The sealing material 73 is attached, and the water tightness may be further improved (see FIG. 2).

  Furthermore, in the resin coating 7, the connection terminal coating 72 may be formed of a soft synthetic resin. This is because when the connection terminal covering portion 72 is formed of a soft synthetic resin, the connection terminal covering portion 72 has a flexible structure, and a change in the flow rate of the cooling water occurs in the cooling water circulation region Sa. In addition, when a vibration shock or the like is applied for some reason from the outside, the connection terminal covering portion 72 can be appropriately deformed with flexibility corresponding to the flow of cooling water or the vibration shock. Thereby, it is possible to prevent the connection terminal covering portion 72 from being broken from the core covering portion 71 (see FIG. 6). Moreover, when the said core coating | coated part 71 and the said connection terminal coating | coated part 72 are integrally formed, the core coating | coated part 71 also becomes a soft resin.

  In the embodiment in which the core cover 71 and the connection terminal cover 72 are different members in the resin cover 7 as described above, a plurality of types having different lengths of the connection terminal cover 72 can be prepared. For example, even if the size of the pump housing 1 to be used is different, the connection terminal covering portion 72 having an appropriate length can be used sufficiently. For example, the lengths of the connection terminal covering portions 72 can be mounted corresponding to the pump housings 1 having different sizes by aligning the short size La and the long size Lb [FIG. (See (C)). Moreover, the thing of the same shape can be diverted for the core coating | coated part 71. FIG.

  With the structure described above, the core covering portion 71 of the resin cover 7 is substantially entirely covered with cooling water, so that almost all of the heat generated in the winding 5 escapes to the cooling water. Further, the connection terminal covering portion 72 has a structure that is constantly cooled by the cooling water circulation region Sa in the rotor chamber 12, and the connection terminal 6 inserted into the connection terminal covering portion 72 is also cooled by the cooling water. Thus, heat conduction to the circuit board 8 to which the connection terminal 6 is connected can be reduced.

(A) is a longitudinal side view of the present invention, and (B) is an enlarged view of the main part of (A). (A) is an expanded sectional view near the connection terminal covering portion, and (B) is an enlarged sectional view showing a connection state between the connecting terminal covering portion and the partition wall portion. (A) is a schematic diagram showing a state in which a ring body is configured by an electromagnetic body, (B) is a transverse plan view of the electromagnetic body, and (C) is a longitudinal side view of the electromagnetic body. (A) is a perspective view with a partial cross section of the electromagnetic body, (B) is a transverse plan view of the resin coating, (C) is a longitudinal side view of the resin coating, and (D) is (A) of (C). FIG. (A) is a longitudinal sectional side view of an embodiment in which the core cover part and the connection terminal cover part are separate materials, (B) is an enlarged view of the main part of (A), and (C) is a connection terminal cover part of different length. It is a principal part expanded sectional view of the resin coating body which comprised this. (A) is the principal part expanded sectional view of embodiment which used the connection terminal coating | coated part as the soft material, (B) is the principal part expansion of embodiment which used the connection terminal coating | coated part of the soft material as a member different from a core coating | coated part. It is sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Pump housing, 5 ... Winding, 4 ... Stator core, 71 ... Core coating | coated part,
72 ... connection terminal covering part, 6 ... connection terminal, 8 ... circuit board, Sa ... distribution area,
Sb: Non-distribution area.

Claims (4)

  A pump housing, a stator core around which windings are wound, a core coating portion that resin-coats the stator core, a connection terminal exposed from the core coating portion, a connection terminal coating portion that resin-coats the connection terminal, A circuit board for controlling a current to the winding, and the core covering portion and the connection terminal covering portion are installed in a cooling water flow area in the pump housing, and the circuit board is in a cooling water non-flow area. An electric water pump characterized by being installed.   2. The electric water pump according to claim 1, wherein the core covering portion and the connection terminal covering portion are integrally formed.   2. The electric water pump according to claim 1, wherein the core covering portion and the connection terminal covering portion are separate members and are connected in a watertight manner.   4. The electric water pump according to claim 1, wherein the connection terminal covering portion is flexible. 5.

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