WO2018131403A1

WO2018131403A1 - Electrically driven oil pump

Info

Publication number: WO2018131403A1
Application number: PCT/JP2017/045643
Authority: WO
Inventors: 豪坂田; 河村　清美; 雄一郎定永
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2017-01-11
Filing date: 2017-12-20
Publication date: 2018-07-19
Also published as: CN110168224A; JPWO2018131403A1

Abstract

This electrically driven oil pump comprises: an oil pump having a pump rotor rotatably supported within a pump chamber located between a pump plate and a pump housing; a rotating shaft affixed to the pump rotor; and a motor which has a motor housing, is directly connected to the rotating shaft, and rotationally drives the pump rotor. Further, the motor-side end surface of the pump housing and the pump housing-side end surface of the motor housing are adjacent to each other. Also, the oil pump and the motor are axially fastened to each other by a plurality of fastening bolts at positions radially inside both the outer diameter of the motor housing and the motor-side outer diameter of the pump housing.

Description

Electric oil pump

The present invention relates to an electric oil pump that electrically drives an oil pump, and more particularly to a structure of an electric oil pump in which a motor unit and an oil pump unit are integrated.

Conventionally, a specific example of an electric oil pump is a combination of an oil pump that circulates a fluid such as oil and an electric motor that drives the oil pump (see, for example, Patent Document 1). FIG. 7A is a longitudinal sectional view showing a configuration example of such a conventional electric oil pump, and FIG. 7B is a transverse sectional view thereof.

As shown in FIG. 7A, the conventional electric oil pump 901 includes the oil pump 902 and the electric motor 903 as described above. The electric motor 903 includes a rotating rotor 904, and a stator 905 fixed to the outside of the outer peripheral surface of the rotor 904. The rotor 904 is configured by arranging a plurality of permanent magnets 904b along the circumferential direction on the outer periphery of the rotating shaft 904a. The rotating shaft 904a is a rotating shaft shared by the electric motor 903 and the oil pump 902. The stator 905 is formed by winding a coil 905b around an insulator 905c attached to a core 905a, and is integrally molded with a motor housing molded with a resin 905d.

The oil pump 902 has an inner rotor 902a and an outer rotor 902b as shown in FIG. 7B. The inner rotor 902a illustrated in FIG. 7B has four external teeth connected to the tip of the rotating shaft 904a. Moreover, the outer rotor 902b illustrated in FIG. 7B has five inner teeth that mesh with the outer teeth. The oil pump 902 performs a pump operation using the gap 902c between the external teeth and the internal teeth.

Then, a bolt 906 is inserted from the motor housing, and the bolt 906 is bolted to the housing of the oil pump 902. Thereby, in the conventional electric oil pump 901, the stator 905 of the electric motor 903 is fixed to the oil pump 902.

However, in the electric oil pump 901, when the oil pump 902 and the electric motor 903 are fastened with the fastening bolts 906, it is necessary to provide a flange 936 around the outer diameter of the motor housing. Thereby, when mounting in a vehicle, the flange 936 may protrude and interfere with other vehicle parts around the electric oil pump 901. In addition, water may enter the motor from the outside through the boundary surface between the resin of the motor housing and the metal surface of the pump housing.

JP 2003-129966 A

The electric oil pump of the present invention includes an oil pump in which a pump rotor is rotatably supported in a pump chamber formed between a pump plate and a pump housing, a rotary shaft fixed to the pump rotor, and a cylindrical motor A motor that has a housing and is directly connected to the rotation shaft and is directly connected to the rotation shaft and rotationally drives the pump rotor. In the electric oil pump, the end surface on the motor side of the pump housing and the end surface on the pump housing side of the motor housing are adjacent to each other in the axial direction of the rotating shaft. The oil pump and the motor are fastened in the axial direction by a plurality of fastening bolts on the inner side of the outer diameter of the motor housing and the outer diameter of the motor side of the pump housing with respect to the axis of the rotary shaft. .

With such a configuration, since the pump housing and the motor housing are fastened and fixed radially inside the outer shape of the motor housing of the motor, the motor does not increase in the radial direction and the electric oil pump is mounted on the vehicle. Improves. In addition, a sealing component is sandwiched between the fastening surfaces, and water can be prevented from entering from the outside.

FIG. 1 is a front view of an electric oil pump according to Embodiment 1 of the present invention. FIG. 2 is a longitudinal sectional view showing a schematic configuration of the electric oil pump as seen from the XX direction in FIG. FIG. 3 is a front view of the electric oil pump according to Embodiment 2 of the present invention. FIG. 4 is a longitudinal sectional view showing a schematic configuration of the electric oil pump as seen from the YY direction in FIG. FIG. 5 is a front view of an electric oil pump according to another configuration example of Embodiment 2 of the present invention. 6 is a longitudinal sectional view showing a schematic configuration of the electric oil pump as viewed from the YY direction in FIG. FIG. 7A is a longitudinal sectional view of a conventional example. FIG. 7B is a cross-sectional view of a conventional example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a front view of an electric oil pump according to Embodiment 1 of the present invention, and FIG. 2 is a longitudinal sectional view showing a schematic configuration of the electric oil pump viewed from the XX direction in FIG.

As shown in FIGS. 1 and 2, the electric oil pump 101 includes an oil pump 201 and an electric motor (hereinafter simply referred to as a motor) 301 that drives the oil pump 201 to be adjacent to each other so that they are integrated. Is unitized. In the center of the electric oil pump 101, a rotation drive shaft (hereinafter referred to as a rotation shaft as appropriate) 305 extends from the motor 301 to the oil pump 201. In the following, the direction in which the rotating shaft 305 extends, that is, the axial direction is the axial direction, and in the plane orthogonal to the axial direction, the direction extending from the center of the rotating shaft 305 is the radial direction, and the direction around the center is the circumferential direction. Will be described. Further, in the axial direction, the side on which the oil pump 201 is disposed will be described as the front, the side on which the motor 301 is disposed will be the rear, the surface on the front side will be the front surface, and the surface on the rear side will be the rear surface.

The oil pump 201 is, for example, an internal gear pump that uses gears of external teeth and internal teeth like the conventional oil pump shown in FIG. 7B. And the electric oil pump 101 provided with such an oil pump 201 is used for the hydraulic pump for transmission of a motor vehicle, etc., for example. In this embodiment, an example will be described in which the motor 301 is a brushless motor in which a rotor rotates by three-phase AC driving using an inverter.

The pump plate 203 and the pump housing 204 that constitute the housing 202 of the oil pump 201 are formed of a metal nonmagnetic material such as aluminum die casting, for example. In addition, you may integrally mold with resin.

The motor housing 302 that houses the motor 301 has a metal frame structure formed by pressing a steel plate, which is a metal plate, with a press. The bracket 303 is made of a thermoplastic resin material such as polyphenylene sulfide resin. The heat radiating plate 304 is made of a nonmagnetic metal material such as aluminum die cast. The housing body of the electric oil pump 101 includes the pump plate 203, the pump housing 204, the motor housing 302, the bracket 303, and the heat radiating plate 304. Here, a sealing member 102 such as an O-ring, for example, is disposed between the above components so as to be waterproof.

In this embodiment, a trochoid curve type pump which is an inscribed gear type is used as the oil pump 201. As a result, the oil pump 201 is used as a pump, as in FIG. 7B, as the pump rotor, the outer rotor 205 having the inner teeth of the trochoidal tooth profile on the inner peripheral side, and the outer teeth meshing with the inner teeth on the outer peripheral side. The inner rotor 206 is provided. In the pump housing 204, the inner rotor 206 is disposed in a space formed inside the outer rotor 205, thereby forming a pump chamber 207 including a gap 207a between the two rotors.

As shown in FIG. 2, the inner rotor 206 is fitted into the front end portion of the rotating shaft 305 and rotates around the rotating shaft 305. On the other hand, the outer rotor 205 has one more internal tooth than the outer tooth of the inner rotor 206. Further, the outer rotor 205 is disposed so as to be rotatable in the pump housing 204 around the position eccentric with respect to the inner rotor 206 connected to the rotation shaft 305 as described above. The outer teeth of the inner rotor 206 mesh with the inner teeth of the outer rotor 205 at a part of the entire circumference, and the outer teeth are inscribed in the inner surface of the outer rotor 205 at various locations around the entire circumference. It is configured to rotate. Moreover, since it is such a structure, the space | gap 207a is formed in the location where the said external tooth and internal tooth are not fully meshing | engaged.

Therefore, when the rotating shaft 305 is driven to rotate by the motor 301, the volume of the gap 207a between the inner teeth and the outer teeth of the oil pump 201 increases and decreases during one rotation of the rotating shaft 305. Will repeat. And the pump operation | movement which sends out the oil inject | poured into the gap | interval 207a by such repetition is performed.

The pump housing 204 has a thick plate shape that expands in the radial direction, and has a circular pump hole 204p opened at the front side at the center thereof. The pump chamber 207 as described above is formed in the pump hole 204p. A pump plate 203 is fixed to the front surface of the pump housing 204 via an O-ring 209 as the seal member 102, and the front surface of the pump chamber 207 is closed. As described above, the outer rotor 205 constituting the oil pump 201 is rotatably accommodated in the pump chamber 207. An inner rotor 206 that meshes with the outer rotor 205 is disposed inside the outer rotor 205. The pump plate 203 is provided with the suction port 210 and the discharge port 211 shown in FIG. The suction port 210 and the discharge port 211 are openings that penetrate in the axial direction, and a suction pipe (not shown) is connected to the suction port 210, and a discharge pipe (not shown) is connected to the discharge port 211. The Then, oil is supplied from the suction pipe to the suction port 210 and the oil pump 201 is operated, whereby the supplied oil is discharged from the discharge port 211 to the discharge pipe.

Next, the motor 301 includes a rotating rotor 306 and a stator 313 disposed outside the outer peripheral surface of the rotor 306. Further, in the motor 301, the stator 313 is fixed inside the motor housing 302 having a cylindrical shape. The front end surface of the motor housing 302 and the rear end surface of the pump housing 204 are fixed to each other. A bracket 303 is attached to the motor housing 302 so as to close the opening on the rear side of the motor housing 302.

The rotor 306 is formed by fixing a rotor core 307 to an intermediate portion of the rotating shaft 305 and arranging a plurality of permanent magnets 308 inside or on the outer peripheral surface of the rotor core 307. In the present embodiment, such a rotating shaft 305 is shared by the motor 301 and the oil pump 201. Further, in the present embodiment, as shown in FIG. 2, the sensor magnet 312 for detecting the rotational position of the rotor 306 is held on the rotating shaft 305 via the holding ring 312a on the rear side of the rotor 306. Yes.

The rotating shaft 305 is supported by a pair of

bearings

309 and 310 so as to be rotatable. That is, first, a cylindrical portion having a smaller diameter than the motor housing 302 is formed at the center of the rear end surface of the pump housing 204, and a cup-shaped bearing housing 212 is inserted into the cylindrical portion. Further, a bearing 309 is fitted inside the bearing housing 212. On the other hand, a cylindrical portion is also formed at the center of the bracket 303, and a cup-shaped bearing housing 311 is inserted and the bearing 310 is fitted. A portion extending to the front side of the rotating shaft 305 is supported by the bearing 309, and a rear end portion of the rotating shaft 305 is supported by the bearing 310. In this example, the

bearings

309 and 310 are both ball bearings which are rolling bearings, and two bearings constitute a double-supported bearing. The inner rings of the

bearings

309 and 310 are fixed to the rotary shaft 305 and the outer rings are fixed to the bearing

housings

212 and 311.

The rotary shaft 305 that is rotatably supported in this way extends forward, penetrates through a hole formed in the rear wall of the pump housing 204, and enters the pump chamber 207. The front end of the rotating shaft 305 is connected to the inner rotor 206. In the present embodiment, an oil seal 208 is provided around the rotary shaft 305 in a portion of the pump housing 204 in front of the bearing 309 in order to prevent oil leakage.

Next, the stator 313 is disposed outside the rotor 306 and faces the outer peripheral surface of the rotor 306 in the radial direction through a slight air gap. The stator 313 includes a stator core 314, an insulator 316, and a coil 315. The stator core 314 includes an annular yoke and a plurality of teeth (not shown) protruding inwardly from the yoke (not shown). In the present embodiment, an example having 12 teeth is given. Each tooth of the stator core 314 is formed with a coil 315 in which a winding is wound via an insulator 316. Here, the insulator 316 is a resin (for example, PPS, polyphenylene sulfide) for insulating the coil 315 from the stator core 314, and is attached to each of the teeth from both ends in the axial direction. Thus, in the present embodiment, a stator subassembly is formed by winding the winding of the coil 315 around one tooth. A stator 313 having a three-phase coil 315 is configured by a plurality of stator subassemblies. The stator 313 is press-fitted into the motor housing 302 and is fixed to the inner periphery of the motor housing 302.

In the motor housing 302, an inlay 302a as shown in FIG. 2 is further formed on the front side. The inlay 302 a is in contact with the outer peripheral surface of the fitting portion 204 a formed on the rear side of the pump housing 204. That is, by fitting the fitting portion 204a of the pump housing 204 into the inlay 302a of the motor housing 302, they are coupled with their centers aligned. At this time, the annular top surface portion 302b on the front surface side of the motor housing 302 and the annular bottom surface portion 204b on the rear surface side of the pump housing 204 are in surface contact. Furthermore, a groove portion 204c that is recessed forward is formed in the bottom surface portion 204b of the pump housing 204. By mounting the O-ring 213 in the groove 204c, the sealing performance with the motor housing 302 is maintained.

Furthermore, in the present embodiment, the motor housing 302 and the pump housing 204 are fixed by a fastening member in a state where the top surface portion 302b of the motor housing 302 and the bottom surface portion 204b of the pump housing 204 are in surface contact. Specifically, a bolt hole 302d through which a bolt passes is provided in the top surface portion 302b of the motor housing 302, and a female screw portion 204d that is a hole for screwing the bolt is provided in the bottom surface portion 204b of the pump housing 204. In the present embodiment, three bolt holes 302d and female screw portions 204d are formed at equal intervals in the circumferential direction with respect to the rotation center. The motor housing 302 and the pump housing 204 are firmly fixed to each other by screwing the fastening bolt 103 into the female screw portion 204d through the bolt holes 302d at these three locations. In the present embodiment, the groove portion 204c and the female screw portion 204d are further formed in the bottom surface portion 204b so that the groove portion 204c is positioned radially outside the female screw portion 204d in the bottom surface portion 204b of the pump housing 204 described above. is doing. In addition, due to the above-described configuration, these fastening bolts 103 are not visible from the pump housing 204 side in FIG. 1, and in FIG. 1, the fastening bolts 103 are indicated by dotted circles.

Also, as shown in FIG. 1, bolt holes are also formed in the outer peripheral edge of the pump plate 203. A pump chamber 207 is formed by bolting a fastening bolt 203a as a fastening member to the pump housing 204 through these bolt holes. In the present embodiment, four fastening bolts 203a are arranged at substantially equal intervals in the circumferential direction with respect to the rotation center.

Further, a control signal for controlling the motor 301 is supplied from an external controller to the electric oil pump 101 of the present embodiment. The electric oil pump 101 has a connector pin in the connector shell of the motor housing 302, and a control signal is connected to the connector pin. The external controller is equipped with an inverter circuit that converts a direct current power source into alternating current and supplies a drive current to each coil 315 of the motor 301, and a control circuit unit that includes a control circuit that controls the inverter circuit.

Then, with the above configuration, a drive current controlled by an external controller is supplied to each coil 315 of the motor 301. As a result, a rotating magnetic field is generated in the coil 315 of the stator 313, torque is generated in the permanent magnet 308 of the rotor 306, and the rotor 306 is rotationally driven. Thus, when the inner rotor 206 is rotationally driven, the outer rotor 205 is driven and rotated, and a gap 207a between the inner teeth of the outer rotor 205 and the outer teeth of the inner rotor 206 is formed. Repeat scaling. By repeating this, a pump operation for sucking and discharging oil through the suction port 210 that is an import and the discharge port 211 that is an outport is performed.

Next, the operation and effect of the electric oil pump 101 of the present embodiment configured as described above will be described.

According to the above configuration, the pump housing 204 of the metal oil pump 201 and the motor housing 302 of the motor 301 are arranged in the axial direction coaxially with the rotation center. The fastening bolt 103 inserted from the inner side of the motor housing 302 is fastened and fixed to the female screw portion 204d of the pump housing 204 through the bolt hole 302d. At this time, in the present embodiment, as described above, the bolt fastening is performed at the location where the top surface portion 302b of the motor housing 302 and the bottom surface portion 204b of the pump housing 204 are in surface contact. For this reason, the fastening bolt 103 is disposed radially inward from the outer diameter of the motor 301. Further, the axial force of the fastening bolt 103 is received by the pump housing 204. And between the fastening surfaces of the pump housing 204 and the motor housing 302, an O-ring 213 mounted on the radially outer side than the position of the fastening bolt 103 is sandwiched. Furthermore, the fitting outer peripheral surface which is the fitting portion 204a of the pump housing 204 and the fitting inner peripheral surface which is the inlay 302a of the motor housing 302 are inlay-fitted and fitted coaxially with the rotation center.

Thus, the electric oil pump 101 does not increase in the radial direction of the motor 301. Further, since the O-ring 213 exists on the outer side in the radial direction of the fastening bolt 103, water does not enter the motor 301 from the outside. In addition, since the motor housing 302 and the pump housing 204 are formed of inlays, the alignment accuracy of the outer rotor 205 and inner rotor 206 in the pump chamber 207 and the stator 313 of the motor housing 302 is improved. As a result, the sealing property between the pump housing 204 of the oil pump 201 and the motor housing 302 is ensured, and the outer rotor 205, the inner rotor 206, and the stator 313 in the pump chamber 207 can be easily assembled. And the mounting property to a vehicle improves by size reduction of the motor 301 in the radial direction.

As described above, according to the present embodiment, it is possible to provide an electric oil pump that can be mounted on a vehicle without increasing the motor in the radial direction.

As described above, the first embodiment according to the present invention has been described, but the present invention can also be implemented in other forms.

(Embodiment 2)
FIG. 3 is a front view of the electric oil pump according to Embodiment 2 of the present invention, and FIG. 4 is a longitudinal sectional view showing a schematic configuration of the electric oil pump viewed from the YY direction in FIG.

In comparison between the first embodiment and the first embodiment, in the first embodiment, the fastening bolt 103 is inserted from the inside of the motor housing 302, the pump housing 204 and the motor housing 302 are fastened, and the fastening bolt 103 is connected. The O-ring 213 is arranged on the outer side in the radial direction. On the other hand, in the present embodiment, as shown in FIGS. 3 and 4, the pump housing 204 has a plurality of bolt through holes 201 a on its outer shell. Then, the fastening bolts 103 are inserted into the bolt through holes 201a from the outer periphery of the pump housing 204 on the pump plate 203 side, and the pump housing 204 and the motor housing 302 are fastened. Here, also in this embodiment, an example of fastening with three fastening bolts 103 is shown. In addition, an O-ring 213 is arranged inside the fastening bolt 103 in the radial direction. That is, these bolt through holes 201 a are formed on the radially outer side of the O-ring 213 that is the seal member 102 and on the radially inner side of the outer diameter of the motor housing 302.

More specifically, the motor housing 302 of the present embodiment is configured such that a non-penetrating flanged collar 317 is press-fitted into the motor frame 319 and a liquid gasket 318 is applied to the flange surface of the flanged collar 317. Further, the flanged collar 317 has a structure having a non-penetrating flange together with the female screw portion. Then, with the fastening bolts 103 respectively inserted into the bolt through holes 201a from the outer portion of the pump housing 204 on the pump plate side toward the motor housing 302, the motor frame 319 is sandwiched between the female thread portion of the flanged collar 317 and the screw. Match. In this way, the pump housing 204 and the motor housing 302 are fastened.

By adopting such a configuration, the electric oil pump 101 can be both downsized and waterproof. Furthermore, when there is a margin in the axial dimension, the thickness of the end face of the motor frame 319 is increased, and an internal thread portion is formed on the end face of the motor frame 319 to reduce the number of parts, thereby constituting the electric oil pump 101. It is possible.

FIG. 5 is a front view of an electric oil pump according to another configuration example of Embodiment 2 of the present invention, and FIG. 6 is a longitudinal sectional view showing a schematic configuration of the electric oil pump viewed from the YY direction in FIG. FIG. In this configuration example, the pump plate 203 and the pump housing 204 having the shapes shown in FIGS. 5 and 6 are provided, and the fastening bolt 103 is inserted from the outer periphery of the pump housing 204 on the pump plate 203 side. 302 is fastened. Such a configuration may be adopted.

In the first and second embodiments, the case where an internal gear type pump is used as the oil pump 201 has been described. However, the present invention is not limited to this, and a rotary pump using a vane drive or an external gear may be used. . Furthermore, as long as it is an internal gear pump in which the volume of the gap 207a repeats expansion and contraction, it is not necessarily limited to the trochoid curve type pump as described above. Further, the inner teeth of the outer rotor 205 and the outer teeth of the inner rotor 206 are not necessarily formed in a clear so-called tooth shape, and may be protrusions, protrusions, or engaging portions.

In the first and second embodiments described above, the case where the motor 301 is applied to the electric oil pump 101 has been described. However, the present invention is not limited to this and is applied to other products using the same motor 301. May be. Furthermore, a motor with a brush can be applied.

In the first and second embodiments, the case where a plurality of permanent magnets 308 are arranged and fixed inside the rotor core 307 as the rotor 306 of the motor 301 has been described. However, a plurality of permanent magnets 308 are fixed to the outer peripheral portion of the rotor core 307. The magnet 308 may be disposed, or one ring-shaped permanent magnet 308 may be fixed.

In the first and second embodiments, the controller is provided separately from the motor 301. However, the present invention is not limited to this. The controller is incorporated in the housing of the electric oil pump 101, and the substrate is mounted. The structure fixed to the rear-end part of the motor housing 302 may be sufficient.

The electric oil pump of the present invention is useful for, for example, a hydraulic pump for automobile transmission.

101,901 Electric oil pump 102 Seal member 103,203a Fastening bolt 201,902 Oil pump 201a Bolt through hole 202 Housing 203 Pump plate 204 Pump housing

204a Fitting portion

204b Bottom portion

204c Groove portion 204p Pump holes 205, 902b

Outer rotor

206 , 902a Inner rotor 207

Pump chamber

207a, 902c Clearance 208 Oil seal 209, 213 O-ring 210 Suction port 211

Discharge port

212, 311 Bearing housing 301 Motor 302 Motor housing 302a Inner 302b Top surface portion 302d Bolt hole 303 Bracket 304

Heat sink plate

305,

904a Rotating shaft

306, 904 Rotor 307 Rotor core 308, 9 4b the

permanent magnets

309 and 310 bearing 312 sensor magnet 312a retaining ring 313,905 stator 314 stator core 315,905b coil 316,905c insulator 317 Color 318 liquid gasket 319 motor frame 903 electric motor 905a core 905d resin 906 volts 936 flange

Claims

An oil pump in which a pump rotor is rotatably supported in a pump chamber formed between a pump plate and a pump housing;
A rotating shaft fixed to the pump rotor;
A cylindrical motor housing, and a motor that is directly connected to the rotating shaft and rotationally drives the pump rotor;
An electric oil pump in which an end surface on the motor side of the pump housing and an end surface on the pump housing side of the motor housing are adjacent to the axial direction of the rotating shaft,
The oil pump and the motor are arranged in the axial direction by a plurality of fastening bolts at a radially inner side than an outer diameter of the motor housing and an outer diameter of the pump housing on the motor side with respect to an axis of the rotating shaft. An electric oil pump characterized by being fastened to.
The oil pump and the motor are connected to the plurality of fastening bolts with a seal member interposed between the end surface of the pump housing on the motor side and the end surface of the motor housing on the pump housing side. The electric oil pump according to claim 1, wherein the electric oil pump is fastened.
The pump housing has a plurality of female screw portions on the radially inner side of the seal member,
The plurality of fastening bolts are screwed into the plurality of female screw portions in a state of being inserted toward the pump housing from the cylindrical inner side of the motor housing. Electric oil pump.
The pump housing has a plurality of bolt through holes on the radially outer side of the seal member and on the radially inner side of the outer diameter of the motor housing,
The motor housing includes a motor frame and a plurality of collars having a female screw portion and a non-penetrating flange,
The plurality of fastening bolts are inserted into the plurality of bolt through holes from the outer portion of the pump housing on the pump plate side toward the motor housing, sandwiching the motor frame, and the plurality of collars The electric oil pump according to claim 2, wherein the electric oil pump is screwed with the female screw portion.
The electric oil pump according to claim 1, wherein the motor housing has a metal frame structure, and the pump housing is integrally formed of metal or resin.
The electric oil pump according to claim 5, wherein the motor housing has a structure in which a metal plate is formed by pressing.
6. The electric oil pump according to claim 5, wherein the pump housing is cast from a metal nonmagnetic material.
The electric oil pump according to claim 7, wherein the pump housing is molded by aluminum die casting.