JP2015151985A - electric fluid pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new electric fluid pump the pump efficiency of which can be restrained from degrading and which enables a problem occurring in its mounting to be solved.SOLUTION: Both metallic partition wall member and a stator segment are insert-molded in a motor housing made of synthetic resin and both ends of the partition wall member are integrally connected in synthetic resin of the motor housing. With this arrangement, more than one effects can be realized as follows, i.e. integral coupling of both ends of the partition member to the synthetic resin of the motor housing enables O-ring used for assuring liquid-sealed condition to be eliminated, resulting in that the number of assembling steps can be reduced or no presence of the O-ring enables a thin partition member to be restricted against its deformation, or it is not necessary to form a flange of complex shape for use in fixing the O-ring to the partition member and a unit price of a component element can be reduced.

Description

  The present invention relates to an electric fluid pump, and more particularly to an electric fluid pump mounted in an engine room of an automobile.

  In recent years, as the demand for reducing fuel consumption of automobiles has increased, commercialization of automobiles with an idling stop function and hybrid cars has progressed. Since these vehicles also stop the fluid pump driven by the internal combustion engine when the internal combustion engine stops, a fluid pump drive source other than the internal combustion engine is required. Moreover, in a hybrid vehicle or an electric vehicle, a driving motor, its control device, or a cooling water pump for cooling the battery is required. From these backgrounds, there is a tendency to increase the use of electric fluid pumps that perform a pump action by applying a rotational force to a rotor on which an impeller is fixed using an electric motor.

  For example, Japanese Patent Laid-Open No. 2010-144893 (Patent Document 1) discloses a space in which a rotor is accommodated in a space communicating with a pump chamber in which an impeller is accommodated, and is liquid-tightly separated from a rotor accommodating space by a partition member. In a canned pump that accommodates a stator including windings, the stator is accommodated in a mold in order to insert-mold the stator in a synthetic resin, and when the motor housing is molded with the synthetic resin, the inner peripheral surface of the stator is covered. There is described an electric fluid pump in which a partition member is integrally formed of synthetic resin by molding with synthetic resin.

JP 2010-144893 A

  By the way, in the electric fluid pump of patent document 1, since a partition member is a synthetic resin, since a partition member cannot fully be thinned from a viewpoint on strength, the air gap between a stator and a rotor expands. There has been a problem that the efficiency of the electric motor is reduced.

  Therefore, it can be considered that the partition member made of synthetic resin is changed to a thin partition member made of a nonmagnetic metal having high strength. Certainly, when a metallic partition member is used, the partition member can be made sufficiently thin as described above, so the air gap between the stator and the rotor can be reduced, and the efficiency of the motor can be improved. It becomes like this.

  However, when it was actually applied to a product, several mounting problems emerged. Specifically, in order to fix the motor housing made of the synthetic resin of the electric fluid pump and the metal partition member in a liquid-tight manner, it is necessary to secure the fluid-tightness between both ends of the partition wall member and the motor housing. There is a need to provide a ring, which causes a problem that the number of parts of an O-ring part increases and the number of assembling steps increases due to the increase in the number of parts. Further, the thin partition member is deformed by the repulsive force of the O-ring, and in some cases, the partition member and the rotor come into contact with each other, resulting in a problem that the reliability of the product is lowered. Furthermore, in order to ensure liquid-tightness with the motor housing, a flange having a complicated shape for attaching an O-ring to the partition member must be formed, and there is a problem that the unit cost of the partition member increases.

  Note that not all of these mounting problems occur, but at least one or more problems occur, and the present invention solves one or more of these problems.

  An object of the present invention is to provide a novel electric fluid pump capable of suppressing a decrease in pump efficiency and solving at least one of the above-described problems in mounting.

  The present invention is characterized in that a metal partition member and a stator portion are insert-molded into a synthetic resin motor housing, and both ends of the partition member are integrally coupled into the synthetic resin of the motor housing.

  According to the present invention, since both ends of the partition wall member are integrally coupled to the synthetic resin of the motor housing, the O-ring for securing liquid tightness can be omitted, and the assembly man-hour can be reduced, or there is no O-ring. One or more effects can be achieved in that the deformation of the thin partition member can be suppressed, or the cost of parts can be reduced without forming a flange having a complicated shape for attaching an O-ring to the partition member. .

1 is an axial sectional view of an electric fluid pump used for an internal combustion engine according to a first embodiment of the present invention. It is the external appearance perspective view which looked at the partition member shown in FIG. 1 from diagonally. It is explanatory drawing explaining the assembly | attachment process of the electric fluid pump shown in FIG. It is an axial sectional view of an electric fluid pump used for an internal combustion engine according to a second embodiment of the present invention. It is an axial sectional view of the partition member shown in FIG.

  Embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments, and various modifications and application examples are included in the technical concept of the present invention. It is included in the range.

  Hereinafter, a first embodiment of an electric fluid pump according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the overall configuration of the electric fluid pump. The electric fluid pump shown in FIG. 1 is a cooling pump that uses cold cooling water as a working fluid and is incorporated in a circulation circuit connected to a radiator that is a heat exchanger. For example, an internal combustion engine or a drive motor in a hybrid vehicle A water pump for supplying cooling water to an inverter or the like.

  The electric fluid pump 10 according to the present embodiment includes a pump unit 11, a motor unit 12 as a driving unit that drives the pump unit 11, and a control unit 13 that controls the operation of the motor unit 12. It is configured as a solid.

  The pump unit 11 includes a pump housing 15 that forms a pump chamber 14 and an impeller 16 that is rotatably accommodated in the pump chamber 14.

  The pump housing 15 has a suction port (not shown) that opens into the pump chamber 14 and a discharge port (not shown) that opens from the outer periphery of the pump chamber 14 to the outside of the pump chamber 14. The pump unit 11 is a centrifugal pump that applies pressure to the cooling water in the radial direction by rotating the impeller 16. When the impeller 16 rotates, the cooling water is sucked into the pump chamber 14 from the suction port, and discharged (pressure-fed) from the discharge port through the discharge channel on the outer peripheral side of the impeller 16.

  The impeller 16 is an impeller having a plurality of blades 17. The impeller 16 is formed integrally with the rotor portion 18 at one end of the rotor portion 18 of the motor portion 12 and is installed in the pump chamber 14. Each blade 17 is arranged radially about the central axis of the rotor portion 18. Each blade 17 is disposed, for example, so as to incline to the opposite side to the rotation direction of the impeller 16 toward the outer diameter side, and is installed in a spiral shape as a whole.

  A movement restricting member 19 that restricts the movement of the rotor portion 18 and the impeller 16 in the axial direction is integrally formed with the pump housing 15 in the pump housing 15. One end of the support shaft 20 of the rotor 18 is inserted in the center of the movement restricting member 19, thereby supporting one end of the support shaft 20.

  The motor unit 12 is a so-called inner rotor type DC brushless motor, and forms a cylindrical stator unit 21, a rotor unit 18 provided on the inner peripheral side of the stator unit 21, and a motor chamber 22 that houses these. The housing 23 has a support shaft 20 that is provided in the motor housing 23 and rotatably supports the rotor portion 18.

  The motor housing 23 is made of synthetic resin, and the stator 21 is integrated with the motor housing 23 by insert molding. Similarly, the support shaft 20 is also integrated by insert molding. The motor housing 23 is made of synthetic resin as described above, and has a bottomed cylindrical shape. And it is embed | buried in the synthetic resin so that the support shaft 20 may be planted in the center vicinity of the circular bottom face part 23A.

  The stator 21 has a plurality of windings 24, and a magnetic flux is generated on the inner peripheral side by energizing the windings 24. The rotor portion 18 has a magnetic pole holding portion 25 and a shaft portion 26 integrally. For example, the rotor portion 18 is formed integrally with the impeller 16 by injection molding a synthetic resin material. The magnetic pole holding part 25 is composed of a permanent magnet and is firmly attached in the rotor part 18 by a synthetic resin. Since the rotor portion 18 comes into contact with the cooling water, it is important that the magnetic pole holding portion 25 is covered with a synthetic resin. The impeller 16 may be fixed to the rotor unit 18 as a separate member from the rotor unit 18.

  The magnetic pole holding portion 25 is a columnar member that is installed so as to face the inner peripheral surface of the stator 21 with a slight gap (air gap) between which a plurality of windings 24 of the stator portion 21 are provided. A plurality of magnetic poles (permanent magnets in which N poles and S poles are alternately arranged in the circumferential direction) are held.

  The shaft portion 26 is a shaft member that transmits power for rotating the impeller 16, and is provided coaxially with the magnetic pole holding portion 25 so as to be hollow. A first bearing holding portion and a second bearing holding portion are formed near the magnetic pole holding portion 25 and the impeller 16 of the rotor portion 18, and a first bearing 27 and a second bearing 28 are installed in these bearing holding portions, respectively. The bearings 27 and 28 are fixed to the rotor 18. The bearings 27 and 28 are both sliding bearings, and the diameters of the inner peripheral surfaces of the bearings 28 and 28 are slightly larger than the diameter of the support shaft 20.

  The support shaft 20 passes through a support hole formed at the center of the rotor 28, and the inner peripheral surface of the bearings 28, 28 fixed to the rotor 18 and the support shaft 20 with the rotor 18 installed on the support shaft 20. There is a slight gap between the outer peripheral surfaces of the two. That is, the bearings 27 and 28 are provided so as to be slidable with respect to the support shaft 20 and are rotatably supported by the support shaft 20 via the bearings 27 and 28 of the rotor 18.

  The stator portion 21 has a plurality of salient pole portions 29A formed integrally with an iron core 29 and wound with a winding 24 via a synthetic resin bobbin. The stator portion 21 includes an arc-shaped tooth formed on the salient pole portion 29A. The rotor portion 18 is located around the circumference. Therefore, the rotor portion 18 is rotated by sequentially applying electric power to the winding 24.

  A controller 29 is attached to the opposite surface of the bottom surface 23A of the motor housing 23 to the side where the rotor 18 is located. The control unit 29 is a driver that supplies a drive current for the motor unit 12, and includes a control housing 31 that forms the substrate housing chamber 30, a substrate 32 on which electronic components are housed in the substrate housing chamber 30, and the like. Yes.

  Electronic circuit elements (CPU, transistor, etc.) are mounted on the substrate 32, and a converter and a control circuit are constituted by these circuit elements and capacitors. The converter receives power supply from a battery which is a DC power supply and supplies AC power to the winding 24 of the motor unit 12. The control circuit controls on / off of the IGBT constituting the converter, and is constituted by a microcomputer or the like.

  A partition wall member 33 is disposed between the stator portion 21 and the rotor 18. The partition member 33 is made of a thin metal plate having a thin cross section. The partition member 33 is formed in a straight cylindrical shape having open ends 33 </ b> A and 33 </ b> B that are open at both ends, and extends along the axial direction of the rotor portion 18. One opening end 33A of the partition member 33 is joined to the side surface portion 23B of the motor housing 23 on the impeller 16 side, and the other opening end 33B of the partition member 33 is embedded to be embedded in the bottom surface portion 23A of the motor housing 23. Yes. Of course, one opening end 33A of the partition wall member 33 may be embedded in the side surface portion 23B of the motor housing 23 on the impeller 16 side. In short, it is only necessary that the opening ends 33A and 33B at both ends of the partition wall member 3 are directly liquid-tightly coupled with the synthetic resin of the motor housing 23.

  As can be seen from the figure, the rotor portion 18 is housed inside the partition wall member 33, and cooling water is introduced into the partition wall member 33. Further, the inner peripheral surface of the arc-shaped tooth formed on the salient pole portion 29A of the stator portion 21 is formed in an arc shape that coincides with the outer peripheral surface of the partition wall member 33, and is in metal contact with the outer peripheral surface of the partition wall member 33. ing. As a result, heat from the copper loss of the winding 24 and heat of the internal combustion engine that is input from the surrounding environment are transferred to the partition member 33 via the salient pole portion 29A, and further transferred to the cooling water to be dissipated. It has become.

  FIG. 2 shows an external appearance of the partition wall member 33 viewed from an oblique direction. The partition member 33 is a thin straight tubular cylinder whose outer diameter is substantially the same as the inner diameter of the teeth of the salient pole portion 29A of the stator portion 21. For example, a nonmagnetic metal material such as austenitic stainless steel is used. By pressing, it is made into a cylinder having open ends 33A and 33B at both ends in the axial direction. The thickness of the partition member 33 can be set to 0.5 mm or less, for example.

  Further, on the entire outer peripheral surface in the vicinity of the opening ends 33A and 33B of the partition wall member 33 to be joined with the synthetic resin forming the motor housing 23, a coupling portion 34 having fine irregularities is formed. The joint 34 enhances the adhesion with the motor housing 23 and improves the liquid tightness. The connecting portion 34 may be an emboss having a fine circular unevenness or a conical unevenness, a knurling having a fine intersecting groove, or a knurling. Thus, the adhesiveness with the synthetic resin can be enhanced by the fine irregularities and the grooves, and the liquid-tightness can be improved by the labyrinth structure formed on the contact surface with the synthetic resin.

  Furthermore, the outer peripheral surface between the joint portions 34 formed at both opening ends 33A and 33B of the partition wall member 33 forms a heat transfer portion 35 having a flat shape. The heat transfer part 35 is in metal contact with the teeth of the salient pole part 29A of the stator part 21, and dissipates heat from the stator part 21 to the cooling water. For this reason, in order to enlarge the contact area with the tooth | gear of the salient pole part 29A, it is set as the flat shape. In order to improve the heat transfer performance due to metal contact, a heat dissipating resin (a thermosetting resin in which aluminum oxide is mixed in a filler) is used to form teeth of the heat transfer portion 35 of the partition wall member 33 and the salient pole portion 29A of the stator portion 21. May be bonded together.

  Furthermore, it is also effective for improving the strength to form fine circular or polygonal unevenness over the entire outer peripheral surface of the partition wall member 33. In this way, by forming irregularities over the entire outer peripheral surface of the partition wall member 33, it is possible to improve the strength due to the shape effect. However, in this case, since the contact area of the salient pole portion 29A with the tooth decreases, the heat transfer property can be sufficiently ensured by adhering them with the above-described heat-dissipating adhesive.

  As described above, in the canned electric fluid pump in which the partition member is installed between the stator portion 21 and the rotor portion 18 so that the cooling water does not enter the stator portion 21 from the rotor portion 18 communicating with the pump chamber. In order to simplify, it can be considered that the partition member is formed of a resin material. However, when the partition member is molded from a resin material, a certain amount of thickness is required in the partition member from the viewpoint of ensuring the flow of molten resin during molding. In the case of a hybrid vehicle, there is a demand for cooling an internal combustion engine using an electric fluid pump. Therefore, when the electric fluid pump is used for cooling, if the resin partition member is too thin, the temperature of the cooling water in contact therewith (in the case of cooling for an internal combustion engine, for example, a temperature up to 120 ° C. for the purpose of pressurization). The partition wall member cracks and the strength and durability of the partition wall member is reduced due to the difference between the ambient temperature and the outside temperature (in winter, for example, a temperature region up to -40 ° C may be expected). However, the waterproof function may be deteriorated. That is, in order to secure the moldability in the manufacturing method and to secure the strength of the partition member in the environment (temperature environment) to be used, a certain thickness of the partition member is required. Therefore, the stator and rotor of the motor There must be a large air gap between them. When the air gap increases, the magnetic force transmitted from the stator to the rotor decreases (in proportion to the square of the distance), and the output of the motor decreases. For this reason, if it is going to maintain the performance of a pump, for example, power consumption will increase and the efficiency of a pump will fall. Alternatively, expensive neodymium or the like is used as a magnet, or the amount of use thereof is increased, resulting in an increase in cost.

  On the other hand, according to the electric fluid pump according to the present embodiment, the material of the partition wall member 33 is a non-magnetic metal, so that it can be thinned in terms of formability. In addition, there is little need to increase the wall thickness in order to ensure strength against the use environment (temperature environment). Thereby, since the air gap between the stator part 21 and the rotor part 18 can be made as small as possible, it is possible to reduce power consumption and improve pump efficiency while downsizing the motor. That is, even when the temperature of the cooling water is relatively high as in an internal combustion engine, the pump can be made smaller and more efficient while suppressing the deterioration of the waterproof function. Moreover, the cost of the magnet required for the manufacture can be reduced and it can be set as a cheaper pump.

  Further, since the teeth inner peripheral surface of the salient pole portion 29A formed on the stator portion 21 and the outer peripheral surface of the partition wall member 33 are brought into metal contact, the air gap is made smaller than when both surfaces are not in contact with each other, and the above effect is achieved. Can be improved.

  Furthermore, when the temperature of the motor unit 12 is high, the winding resistance increases, the magnetic force of the permanent magnet decreases, and the performance of the motor unit 12 decreases. Further, the electronic components constituting the drive control unit are affected by heat. The problem of receiving and deteriorating will arise. On the other hand, the heat transfer part 35 formed on the partition wall member 33 can dissipate the heat from the stator part 21 to the cooling water by making metal contact with the teeth of the salient pole part 29A of the stator part 21, thereby The efficiency of the motor unit 12 can be improved.

  Since the metal material used for the partition member 33 is required to be nonmagnetic, for example, nonmagnetic austenitic stainless steel (for example, SUS304) can be used. Moreover, it is preferable that the thickness of the partition member 33 is, for example, such that the deterioration of the partition member 33 is within an allowable range even when repeatedly exposed to a predetermined temperature difference. In the present embodiment, since the thickness of the partition wall member 33 in the portion of the salient pole portion 29A formed on the stator portion 21 that contacts the inner peripheral surface of the tooth is 0.5 mm or less, the strength of the partition wall member 33 is within the allowable range. The thickness of the air gap can be made as small as possible to further reduce the air gap.

  Next, the manufacturing method of the motor part 12 is demonstrated using FIG. As described above, the motor housing 23 according to the present embodiment is formed of synthetic resin. Therefore, when the motor housing 23 is formed of this synthetic resin, the stator portion 21 and the partition member 33 are simultaneously insert-molded and integrated.

  As shown in FIG. 3, the support shaft 20, the stator portion 21, and the partition wall member 33 are set in a predetermined mold K. In this case, the support shaft 20 and the partition wall member 33 are located in the stator portion 21. In the actual mold K, the support shaft 20, the stator portion 21, and the partition member 33 are set in combination. The stator portion 21 is assembled with a winding 24 and an input terminal 24A, a neutral terminal 24B, an iron core 29, etc. connected to the winding 24.

  In this state, when the synthetic resin melted from the resin injection machine M is injected into the mold K, the motor housing 23 in which the support shaft 20, the stator portion 21, and the partition wall member 33 are integrated is formed. The motor housing 23 completed by injecting synthetic resin on the left side of FIG. 3 is shown. As can be seen from this figure, the support shaft 20 is embedded in the bottom surface portion 23A of the motor housing 23 and planted in the starter portion 21, and the opening end 33B of the partition wall member 33 is embedded in the bottom surface portion 23A of the motor housing 23. The opening end 33 </ b> A of the partition wall member 33 is joined to the side surface portion 23 </ b> B of the motor housing 23.

  Thus, by integrating the partition member 33 into the motor housing 23 by insert molding, the following operations and effects can be achieved.

  As described above, if the partition member is made of synthetic resin, the partition member cannot be made sufficiently thin from the viewpoint of strength. Therefore, the air gap between the stator portion 21 and the rotor portion 18 is enlarged, and the motor efficiency is increased. There was a problem that would decrease. In order to solve this problem, it can be considered that the partition member made of synthetic resin is changed to a thin partition member made of a nonmagnetic metal having high strength. Certainly, when a metallic partition member is used, the partition member can be made sufficiently thin as described above, so the air gap between the stator and the rotor can be reduced, and the efficiency of the motor can be improved. It becomes like this. This is as already described.

  However, when it is actually applied to a product, several mounting problems occur. For example, in order to fix the motor housing 23 made of synthetic resin of the electric fluid pump 10 and the metal partition wall member 33 in a liquid-tight manner, the liquid-tightness is set between the both ends 33A and 33B of the partition wall member 33 and the motor housing 23. In order to ensure, it is necessary to provide an O-ring, resulting in an increase in the number of components and an increase in the number of assembly steps due to the increase in the number of components. Further, the thin partition member is deformed by the repulsive force of the O-ring, and in some cases, the partition member and the rotor come into contact with each other, resulting in a problem that the reliability of the product is lowered. Furthermore, in order to ensure liquid-tightness with the motor housing, a flange having a complicated shape for attaching an O-ring to the partition member must be formed, resulting in a problem that the unit cost of the partition member increases.

  On the other hand, in this embodiment, the opening ends 33A and 33B at both ends of the partition wall member 33 are configured to be joined to the synthetic resin forming the motor housing 23, so that the above-described problems can be solved. It is. That is, one opening end 33B of the partition member 33 is directly embedded in the synthetic resin of the motor housing 23, and the outer periphery of the other opening end 33A of the partition member 33 is directly bonded to the synthetic resin of the motor housing 23. By doing so, two O-rings can be omitted, and as a result, problems such as an increase in the number of parts and an increase in the number of assembly steps caused by the increase in the number of parts can be solved.

  Moreover, since there is no O-ring, the thin partition member 33 is deformed by the repulsive force of the O-ring, and the partition member 33 and the rotor portion 18 come into contact with each other. is there.

  Further, since the partition wall member 33 is a straight tube, it is not necessary to form a flange having a complicated shape for attaching an O-ring, so that the problem that the unit cost of the partition wall member 33 is increased can be solved.

  In addition, as shown in FIG. 2, since the coupling portion made of irregularities and grooves is provided on the outer peripheral surface of the opening ends 33 </ b> A and 33 </ b> B of the partition wall member 33, the adhesion performance with the synthetic resin forming the motor housing 23 Can be improved, and the liquid tightness can be enhanced.

  Furthermore, since the flat heat transfer portion 35 is provided between the coupling portions 33A and 33B of the partition wall member 33, the contact area with the teeth of the salient pole portion 29A of the stator portion 21 increases, and the stator portion The heat from 21 can be efficiently radiated to the cooling water.

  Furthermore, by forming irregularities over the entire outer peripheral surface of the partition wall member 33, it is possible to improve the strength due to the shape effect. Moreover, heat conductivity can fully be ensured by adhere | attaching both with a heat dissipation adhesive.

  Next, a second embodiment of the present invention will be described. The difference from the first embodiment is that a retaining portion extending outward is formed at the opening end 33A of the partition wall member 33. Since the other configuration is the same as that of the first embodiment, a detailed description thereof will be omitted.

  In the first embodiment, since the partition wall member 33 is formed in a straight tube shape and is not formed with a retaining portion, the temperature rises and falls repeatedly at the joint portion between the partition wall member 33 and the synthetic resin of the motor housing 23. Thus, it is conceivable that the partition wall member 33 falls off the motor housing 23 due to the difference in thermal expansion coefficient. When the partition member 33 is detached from the motor housing 23, the rotor portion 28 and the partition member 33 interfere with each other, so that the motor portion 12 loses its function as a motor, and the reliability as the electric fluid pump 10 is lost. .

  Therefore, this embodiment is characterized in that a retaining portion is formed in the partition wall member 33 as shown in FIGS. 4 and 5, a retaining portion 36 that is bent outward at an angle of 90 ° with respect to the surface of the partition member 33 is formed at the opening end 33 </ b> A on the pump unit 11 side of the partition member 33. As in FIG. 3, the support shaft 20, the stator portion 21, and the partition member 33 are combined and set in the mold K. In this state, when the synthetic resin melted from the resin injection machine M is injected into the mold K, the motor housing 23 in which the support shaft 20, the stator portion 21, and the partition wall member 33 are integrated is formed.

  As shown in FIG. 4, the retaining portion 36 of the partition wall member 33 is embedded at a right angle to the surface of the side surface portion 23 </ b> B of the motor housing 23, so that even if the partition member 33 is about to fall off, the retaining portion 36. This prevents the partition member 33 from falling off the motor housing 23.

  Thereby, since the partition member 33 does not fall off from the motor housing 23, the motor part 12 can maintain the function as a motor, and the reliability as the electric fluid pump 10 can be improved. Since the retaining portion 36 simply bends the opening end 33A of the partition member 33 by 90 °, the work is easy, and the increase in the unit price of the parts is slight.

  Here, even if the retaining portion 36 of the partition wall member 33 is provided at the opening end 33B, the retaining effect can be obtained in the same manner, and therefore, the basic idea may be provided in either one. However, in this embodiment, the following effects can be newly expected by providing the pump unit 11 side.

  In the first embodiment shown in FIG. 3, when the retaining portion 36 of the partition wall member 33 is provided at the opening end 33B on the bottom surface portion 23A side of the motor housing 23, the opening end 33A of the partition wall member 33 on the pump portion 11 side is Only one linear contact portion between the outer peripheral surface of the opening end 33A and the side surface portion 23B of the motor housing 23 is provided. Therefore, the problem that liquid-tight performance is inferior occurs in this portion.

  On the other hand, in the present embodiment shown in FIG. 4, when the retaining portion 36 of the partition wall member 33 is provided at the opening end 33 </ b> A of the partition wall member 33 on the pump portion 11 side, the retaining portion 36 is against the side surface portion 23 </ b> B of the motor housing 23. Therefore, it is in a close contact state in a form sandwiched between synthetic resins. Therefore, the liquid tightness can be improved at this portion. In addition, since the opening end 33B of the partition member 33 is also positioned at a right angle to the bottom surface portion 23A of the motor housing 23, the partition member 33 is brought into close contact with the synthetic resin. Therefore, the liquid tightness can be improved in the same way.

  As described above, according to the present invention, the metal partition wall member, the stator portion, and the synthetic resin motor housing are insert-molded, and both ends of the partition wall member are coupled into the synthetic resin of the motor housing.

  According to this, by integrally connecting both ends of the partition member into the synthetic resin of the motor housing, the O-ring for ensuring liquid tightness can be omitted and the assembly man-hour can be reduced, or there is no O-ring. One or more effects can be achieved in that the deformation of the thin partition member can be suppressed, or the cost of parts can be reduced without forming a flange having a complicated shape for attaching an O-ring to the partition member. .

  DESCRIPTION OF SYMBOLS 10 ... Electric fluid pump, 11 ... Pump part, 12 ... Motor part, 13 ... Control part, 14 ... Pump chamber, 15 ... Pump housing, 16 ... Impeller, 17 ... Blade | wing, 18 ... Rotor part, 19 ... Movement control member, DESCRIPTION OF SYMBOLS 20 ... Support shaft, 21 ... Stator part, 22 ... Motor chamber, 23 ... Motor housing, 24 ... Winding, 25 ... Magnetic pole holding part, 26 ... Shaft part, 27, 28 ... Bearing, 29 ... Iron core, 29A ... Salient pole 33, partition member, 33A, 33B ... open end, 34 ... coupling part, 35 ... heat transfer part 36 ... retaining part.

Claims (8)

A pump unit for conveying cooling water, a motor unit composed of a rotor unit and a stator unit, a control unit for driving and controlling the motor unit, and a winding wound around the stator unit with a drive signal from the control unit In the electric fluid pump that drives the pump unit by rotating the rotor unit of the motor unit by supplying to the wire,
A cylindrical partition member made of a nonmagnetic metal that separates the stator unit and the rotor unit is provided between the stator unit and the rotor unit, and the rotor unit is rotatable inside the partition member. And the cooling water from the vicinity of the pump part is introduced,
Furthermore, both ends open ends of the stator part and the partition member are insert-molded in a motor housing made of synthetic resin, and the open ends of both ends of the partition member are integrally coupled in the synthetic resin of the motor housing. Electric fluid pump characterized by The electric fluid pump according to claim 1,
The outer peripheral surface of the opening end at both ends of the partition member is formed with a coupling portion made of unevenness or a groove, and at least the coupling portion and a synthetic resin forming the motor housing are in close contact with each other. Electric fluid pump. The electric fluid pump according to claim 2,
The stator portion includes a tooth having an arc formed on a salient pole portion extending inward, and an outer peripheral surface of the partition member is in contact with the arc of the tooth. . In the electric fluid pump according to claim 3,
A flat heat transfer portion that contacts the teeth is formed on the outer peripheral surface of the partition member between the coupling portions formed on the outer periphery of the opening end at both ends of the partition member. Electric fluid pump. The electric fluid pump according to any one of claims 1 to 4,
The electric fluid pump according to claim 1, wherein an orientation stop portion embedded in a synthetic resin forming the motor housing is formed at one opening end of the partition member. In the electric fluid pump according to claim 5,
The electric fluid pump according to claim 1, wherein a retaining portion provided in the partition member is formed at the opening end located on a pump portion side of the motor housing. The electric fluid pump according to claim 6,
The retaining portion formed at the opening end of the partition member located on the pump portion side of the motor housing is bent at an angle of about 90 ° with respect to the surface of the partition member. An electric fluid pump characterized. The electric fluid pump according to claim 4,
An electric fluid pump characterized in that a contact surface between the outer peripheral surface of the partition member and the arc of the teeth portion is fixed by a heat dissipating adhesive.

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