Motor pump

Abstract

A motor pump, applied to the technical field of automotive active suspensions. The motor pump comprises a controller module (110), a motor module (120), and a pump module (130); the controller module (110) is configured to send a driving signal to the motor module (120), so as to drive the pump module (130); the controller module (110) comprises a controller housing (111) and a controller assembly (112); the motor module (120) comprises a motor housing (121) and a motor assembly (122); the pump module (130) comprises a pump cover (131) and a pump body (132); the controller assembly (110) is electrically connected to the motor assembly (122); the motor assembly (122) is connected to the pump body (132); the pump body (132) is located inside the motor housing (121), the pump cover (131) protrudes from the motor housing (121), and the pump module (130) is coaxially connected to the motor module (120); and the controller housing (111) and the motor housing (121) are stacked. In the motor pump, a flow path of a pump head leakage medium is optimized, so that more hydraulic oil flows through a rotor cavity to take away the heat of a motor, and finally flows to a pump head low-pressure oil cavity by means of a one-way valve, thereby improving the heat dissipation effect and improving the working duration and service life of the motor pump.

Description

motor pump Technical Field

[0001] This invention relates to the field of automotive active suspension technology applications, and in particular to an electric motor pump. Background Technology

[0002] The suspension motor pump is an electric hydraulic pump installed in a vehicle that drives the shock absorbers to achieve Z-axis displacement control of the wheels.

[0003] In related technologies, suspension motor pumps are typically designed as an integrated unit of electronic control, motor and oil pump, with the controller and oil pump installed at both ends of the motor, and the three are set up in a coaxial configuration.

[0004] However, in the related technology, after the leaking medium from the oil pump flows into the motor rotor cavity, it immediately flows out from the one-way valve on the pump body. The leaking medium does not flow extensively in the rotor cavity, and most of the heat dissipation for the motor is natural convection. Summary of the Invention

[0005] This invention optimizes the design of the leakage oil circuit in the electric pump and positions the check valve on the pump cover. This ensures that most of the leaking medium flows into one end of the rotor cavity and out the other end, returning to the pump cover cavity via the motor shaft, and then back through the check valve. This achieves forced convection cooling of the medium and increases the flow rate of the medium into the rotor cavity, improving the motor's heat dissipation effect. Consequently, the electric pump can operate for a longer period, improving its performance and lifespan.

[0006] The electric pump includes a controller module, a motor module, and a pump module.

[0007] The controller module is used to send drive signals to the motor module to drive the pump module;

[0008] The controller module includes a controller housing and controller components;

[0009] The motor module includes the motor housing and motor components;

[0010] The pump module includes a pump cover and a pump body;

[0011] The controller assembly is electrically connected to the motor assembly;

[0012] The motor assembly is connected to the pump body;

[0013] The pump body is located inside the motor housing, the pump cover protrudes from the motor housing, and the pump module is coaxially connected to the motor module.

[0014] The controller housing and the motor housing are stacked together;

[0015] The pump module internally forms a pump cover cavity and a pump body cavity;

[0016] The pump body and motor housing form the motor rotor cavity;

[0017] The pump cover cavity, pump body cavity, and motor rotor cavity are used to form a medium passage. The medium flows into the motor rotor cavity through the pump body cavity to achieve forced convection heat transfer.

[0018] In one optional embodiment, the motor housing and the controller housing are implemented as an integrated housing;

[0019] The integrated outer shell forms a first chamber, a second chamber, and a third chamber.

[0020] The first chamber is used to house the motor assembly and the pump body;

[0021] The second chamber is used to house the controller assembly;

[0022] The third chamber is used to house external devices.

[0023] In one alternative embodiment, the motor assembly includes a motor shaft and a motor rotor;

[0024] The motor shaft passes through the pump body;

[0025] The motor rotor is connected to the motor shaft and is used to drive the motor shaft;

[0026] The first end of the motor shaft is connected to the pump body and is used to drive the gears of the pump body.

[0027] The second end of the motor shaft is used for speed signal excitation.

[0028] In an optional embodiment, the motor assembly further includes a sliding bearing for supporting a first end of the motor shaft.

[0029] In an optional embodiment, the motor assembly further includes a shielding sleeve, a sealing ring, and a support ring;

[0030] The shielding sleeve, motor coil, and support ring are located inside the first chamber;

[0031] The shielding sleeve is used to seal the rotor cavity within the first chamber;

[0032] The sealing ring is located at the connection between the shielding sleeve and the pump body and the inner surface of the first chamber;

[0033] The support ring is used to support the shielding sleeve.

[0034] There is a support ring at each end of the shielding sleeve, with the support ring closer to the pump body being encased in plastic inside the shielding sleeve.

[0035] In an optional embodiment, the motor shaft is implemented as a hollow motor shaft;

[0036] When the motor pump moves, the medium flows from the second end of the motor shaft to the first end of the motor shaft;

[0037] When the motor shaft is connected to the pump body cavity, the bushing of the motor shaft has an oil groove.

[0038] In one alternative embodiment, the pump module includes a pump cover housing, a media exchange port, and a check valve;

[0039] The medium exchange port is located on the top of the pump cover housing and is used to exchange the medium that powers the motor and pump.

[0040] When the pump module is working, a high-pressure pump cover cavity and a low-pressure pump cover cavity are formed inside the pump module;

[0041] A check valve is used to selectively transfer high-pressure media leaking in the media passage from the high-pressure pump cover cavity to the low-pressure pump cover cavity.

[0042] In one optional embodiment, there are two media exchange ports and two oil ports.

[0043] The pump cover housing has a one-way valve mounting hole;

[0044] The check valve is located inside the check valve mounting hole;

[0045] The one-way valve mounting hole and the pump cover cavity form a medium passage;

[0046] The check valve is equipped with a check valve plug, which is located inside the check valve mounting hole.

[0047] In an optional embodiment, the oil passages formed by the two check valve mounting holes are parallel to each other;

[0048] or,

[0049] The oil passage formed by the two check valve mounting holes forms an obtuse angle.

[0050] In one alternative embodiment, the external device includes at least one of an external wiring connection and a speed sensor.

[0051] The technical effects included in the various embodiments of the present invention include at least the following:

[0052] When designing the pump body structure assembly of the electric motor pump, the coaxial arrangement of the controller module and the motor module ensures the normal operation of the electric motor pump. A forced convection heat exchange cavity is formed inside the electric motor pump structure to achieve forced convection heat exchange. The heat inside the motor is carried away by the leaked medium, which improves the heat dissipation effect of the motor. This allows the electric motor pump to work for a longer time, improving the performance and life of the electric motor pump. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 shows a structural block diagram of an electric motor pump provided by an exemplary embodiment of the present invention.

[0055] Figure 2 shows a schematic diagram of the structure of an electric motor pump provided by an exemplary embodiment of the present invention.

[0056] Figure 3 shows a schematic diagram of the oil circuit structure of an electric motor pump according to an exemplary embodiment of the present invention.

[0057] Figure 4 shows a partial cross-sectional schematic diagram of a pump module provided in an exemplary embodiment of the present invention.

[0058] Figure 5 shows a schematic diagram of a combination of an axial compensation structure and a radial compensation structure provided by an exemplary embodiment of the present invention.

[0059] Figure 6 shows a top view of a pump module structure provided by an exemplary embodiment of the present invention.

[0060] Figure 7 shows a schematic diagram of the oil circuit direction of an electric motor pump provided by an exemplary embodiment of the present invention.

[0061] Figure 8 shows a cross-sectional schematic diagram of a motor shaft sleeve inside a pump body cavity provided by an exemplary embodiment of the present invention.

[0062] Figure 9 shows a cross-sectional schematic diagram of a motor shaft sleeve inside a pump cover cavity provided by an exemplary embodiment of the present invention. Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0064] The motor pump shown in the embodiments of the present invention can be applied to industrial transmissions and also to automotive active suspensions, serving as an oil pump to supply oil to the shock absorbers.

[0065] Figure 1 shows a structural block diagram of an electric motor pump according to an exemplary embodiment of the present invention. Figure 2 shows a structural schematic diagram of an electric motor pump according to an exemplary embodiment of the present invention. Figure 3 shows a schematic diagram of the oil circuit structure of an electric motor pump according to an exemplary embodiment of the present invention. Please refer to Figures 1 through 3. The motor pump includes a controller module 110, a motor module 120, and a pump module 130. The controller module 110 is used to send drive signals to the motor module 120 and transmit electrical energy. The motor module converts electrical energy into mechanical energy to drive the pump module 130. The controller module 110 includes a controller housing 111 and a controller assembly 112. The motor module 120 includes a motor housing 121 and a motor assembly 122. The pump module 130 includes a pump cover 131 and a pump body 132. The controller assembly 112 is electrically connected to the motor assembly 122. The motor assembly 122 is connected to the pump body 132. A portion of the pump body 132 is located inside the motor housing 121, and the pump cover 131 protrudes from the motor housing 121. The pump module 130 and the motor module 120 are coaxially connected. The controller housing 111 and the motor housing 121 are stacked.

[0066] In this case, please refer to Figure 3. The pump module is internally formed with a pump cover cavity 210 and a pump body cavity 220.

[0067] In this embodiment of the invention, there is no direct oil passage design between the pump cover cavity and the pump body cavity.

[0068] The pump body and the motor housing form a motor rotor cavity 230;

[0069] The pump cover cavity 210, pump body cavity 220 and motor rotor cavity 230 are used to form a medium passage, through which the medium flows into the motor rotor cavity to achieve forced convection heat transfer.

[0070] In this embodiment of the invention, the pump module is an internal gear pump module. Referring to Figure 3, during the operation of the electric motor, a high-pressure oil chamber 240 and a low-pressure oil chamber 250 are formed within the pump body cavity. The positions of the high-pressure oil leakage area and the low-pressure oil area will change according to the four-quadrant working principle of the internal gear pump. This invention does not limit the specific positions of the high-pressure oil leakage area and the low-pressure oil area. In this embodiment of the invention, referring to Figure 4, the medium leakage from the high-pressure oil chamber first flows into the high-pressure oil chamber 240 in the pump body cavity, then flows through the high-pressure oil chamber 240 into the motor rotor cavity 230, and finally flows into the low-pressure oil chamber 250. During the operation of the electric pump, the flow of the medium plays a role in forced convection cooling of the motor.

[0071] In summary, the electric motor pump provided in this embodiment of the invention ensures the normal operation of the electric motor pump by coaxially setting the controller module and the motor module during the design of the pump body structure assembly. It also forms a cavity inside the electric motor pump structure that enables forced convection heat transfer, thereby achieving forced convection heat transfer. The leaked medium carries away the heat inside the motor, improving the heat dissipation effect of the motor. This allows the electric motor pump to work for a longer period of time, improving the performance and lifespan of the electric motor pump.

[0072] Next, the optimized design within the motor pump will be described in the actual application scenario corresponding to the suspension motor pump in the embodiments of the present invention.

[0073] In an optional embodiment, the motor housing 121 and the controller housing 111 are implemented as an integrated housing 140; the integrated housing forms a first chamber 141, a second chamber 142 and a third chamber 143; the first chamber 141 is used to house the motor assembly 122 and the pump body 132; the second chamber 142 is used to house the controller assembly 112; and the third chamber 143 is used to house the external device 150.

[0074] That is, in this embodiment of the invention, the controller module, motor module, and pump module are implemented as an integrated design structure. This structure can be implemented as interconnected metal frames, which can be connected by bolts. The invention does not limit the specific connection method between the metal frames.

[0075] In one alternative embodiment, the external device includes at least one of an external wiring connection and a speed sensor.

[0076] In this case, the specific structure can be referred to in Figure 2. When the motor housing and controller housing are combined, they are divided into three chambers. The first chamber is the motor chamber, which is used to install the motor assembly. The left side of the first chamber is designed with a bearing cavity for installing the motor rotor bearing. The left side of the bearing cavity is designed with a bearing cover to seal the rotor cavity. The right side of the first chamber is designed with a motor cover to house the pump body of the pump assembly. The second chamber is located to the left of the first chamber and is used for the three-phase lines of the motor and the installation of the speed sensor. The second chamber is designed with a rear end cover for sealing. The third chamber is located on the upper part of the housing and is used to install the controller. The third chamber is connected to the second chamber. The third chamber is designed with an upper cover for sealing. The third chamber is designed with high and low voltage connector mounting holes for installing high and low voltage connectors.

[0077] In an optional embodiment, referring to FIG2, the motor assembly 122 includes a motor shaft 1221 and a motor rotor 1222; the motor shaft 1221 extends into the pump body 132; the motor rotor 1222 is connected to the motor shaft 1221 for driving the motor shaft 1221; a first end of the motor shaft 1221 is connected to the pump cover 131 for driving the pump assembly; a second end of the motor shaft 1221 is electrically connected to a third chamber 143 for connecting external equipment. In this case, the motor shaft 1221 is a hollow motor shaft. The hollow design in the middle of the motor shaft is to allow the medium to flow from the bottom of the rotor chamber into the pump cover chamber, while reducing the moment of inertia and improving the response time.

[0078] In this embodiment of the invention, the medium flowing into the rotor cavity permeates the entire rotor cavity, flows to the other end of the rotor cavity, flows into the oil hole of the magnet bolt at the other end, and flows into the second end of the motor shaft; throughout the process, it undergoes forced convection heat exchange with the motor stator and rotor, carrying away the heat generated by the motor. In order to allow more medium to flow into the rotor cavity for heat dissipation, there is no oil passage design below the pump cover bearing, ensuring that as much leakage medium as possible flows into the rotor cavity before returning to the oil.

[0079] In this embodiment of the invention, with the motor shaft inserted into the pump body, the motor rotor is connected to the motor shaft to drive it; the first end of the motor shaft is connected to the pump body to drive the gears of the pump body. The second end of the motor shaft is used for speed signal excitation.

[0080] In an optional embodiment, the motor assembly 122 further includes a shielding sleeve 1223, a sealing ring 1224, and a support ring 1225; the shielding sleeve 1223 and the support ring 1225 are located inside the first chamber; the shielding sleeve 1223 is used to seal the first chamber and to form a rotor cavity; the sealing ring 1224 is located at the connection between the shielding sleeve 1223 and the pump body and the inner surface of the first chamber; the support ring 1225 is used to support the shielding sleeve 1223. In this embodiment of the invention, there are two sealing rings 1224 and two support rings 1225, located on the side closer to the pump body cavity and the side farther from the pump body cavity, respectively. It should be noted that the end of the support ring 1225 closer to the pump body cavity is plastic-coated inside the shielding sleeve.

[0081] In an optional embodiment, referring to FIG4, the pump module includes a pump cover housing 1311 and an oil pumping component 1312. The oil pumping component 1312 is located inside the pump body cavity, and a receiving cavity and a medium passage are formed inside the pump module. When the receiving cavity is formed inside the pump cover housing 1311, the oil pumping component 1312 is located inside the receiving cavity. In this embodiment of the invention, to achieve clearance compensation during operation, referring to FIG5, the oil pumping component 1312 has an axial compensation structure 21 and a radial compensation structure 22. The axial compensation structure 21 is used to compensate for the axial clearance of the oil pumping component when the gear pump operates in the four-quadrant working mode. The radial compensation structure 22 is used to reduce the radial clearance of the oil pumping component when the gear pump operates in the four-quadrant working mode.

[0082] Next, referring to Figure 5, the axial compensation structure and radial compensation structure involved in the embodiments of the present invention will be described:

[0083] In an optional embodiment, the axial compensation structure 21 includes an axial plate 211, and the radial compensation structure 22 includes an oil distribution plate 221 and an oil distribution plate frame 222. The axial plate 21 has at least one through hole. The surface of the oil distribution plate frame 222 includes at least one slot, and the number and position of the through holes correspond to the number and position of the slots. The oil distribution plate 221 and the slotted surfaces of the oil distribution plate frame 222 are fitted together to form an oil passage. When the four-quadrant internal gear pump is operating, the medium passes through the passage formed by the through hole and the oil passage.

[0084] In this configuration, the axial plate 21 is implemented as an axisymmetric structure. The axial plate 21 includes a first through hole 211, a second through hole 212, a third through hole 213, a fourth through hole 214, and a recessed groove 215. The first through hole is located at the axis of the axisymmetric structure and is implemented in an axisymmetric shape for positioning and installation. In practical applications, the first through hole can be a circular through hole to mate with the stop pin 223 shaft. There are two recessed grooves, two second through holes, and two third through holes, distributed symmetrically. The second and third through holes are located inside the recessed groove. The recessed groove has a connecting portion for the passage of medium. The second and third through holes are used to connect the inlet and outlet ports of the pump cover. The fourth through hole is located at the axis of the axisymmetric structure and forms a passage for leaked medium to flow when the pump head component is working. In an optional embodiment, the number and position of the distribution plate and distribution plate bracket correspond to the recessed groove, and the radial compensation structure also includes a stop pin 223. The stop pin 223 contacts the oil distribution plate 221 and the oil distribution plate frame 222 to support the oil distribution plate 221 and the oil distribution plate frame 222. The stop pin is used to limit the relative displacement of the oil distribution plate and the oil distribution plate frame.

[0085] It should be noted that, in this embodiment of the invention, a medium exchange port for the main oil circuit circulation and a one-way valve and its corresponding one-way valve mounting hole for realizing internal circulation are designed. Figure 6 shows a top view of a pump cover provided by an exemplary embodiment of the present invention. That is, in this embodiment of the invention, the pump module 130 includes a pump cover housing 1311, a medium exchange port 321, and a one-way valve 3212;

[0086] The medium exchange port 321 is located on the top of the pump cover housing 1311, and the medium exchange port 321 is used to exchange the medium that powers the motor pump.

[0087] When the pump module 130 is working, a high-pressure pump cover cavity 240 and a low-pressure pump cover cavity 250 are formed inside the pump module 130.

[0088] The one-way valve 3212 is used to selectively transfer high-pressure medium leaking in the medium passage from the high-pressure pump cover cavity 240 to the low-pressure pump cover cavity 250.

[0089] In some embodiments of the present invention, please refer to Figures 4 and 6. The pump cover housing 1311 has two medium exchange ports 321 for adapting the medium entry and exit of the main oil circuit.

[0090] The pump cover is designed with two one-way valve mounting holes 3213, which are designed in the same plane and can be designed at 180° or at an obtuse angle. That is, the oil passages formed by the two one-way valve mounting holes 3212 can be parallel to each other or form an angle. Optionally, the angle can be at least one of acute and obtuse angles. In a preferred case, for the sake of compact structure, the angle is made obtuse. One end of the one-way valve mounting hole 3212 is connected to the pump cover volume cavity 210; the other end is designed with a plug 3214 for sealing. The one-way valve mounting hole and the pump cover cavity form a medium passage, which is adapted to the function of the one-way valve, selectively transporting the high-pressure leakage in the medium passage from the high-pressure pump cover cavity to the low-pressure pump cover cavity. Optionally, this application does not limit the form of the medium passage. As shown in Figure 4, the medium passage can be implemented as a straight oil passage.

[0091] Referring to Figure 7, in this embodiment of the invention, with the high-pressure oil chamber 240 and low-pressure oil chamber 250 pre-set as shown, after leakage in the high-pressure oil chamber, the high-pressure medium enters the pump body chamber 220 and then rotates into the rotor chamber 230. From the end of the rotor chamber 230 away from the pump cover, it enters the oil passage formed inside the hollow motor shaft and then enters the pump cover chamber 210 through the motor shaft. After entering the pump cover chamber, it enters the low-pressure oil chamber 250 through the oil passage where the one-way valve 3212 is located, thus forming a cavity inside the motor pump structure that can perform forced convection heat transfer, thereby achieving forced convection heat transfer. During this process, the pump cover chamber 210 will remain at a low pressure.

[0092] To achieve the above-mentioned oil circuit design, in this embodiment, please refer to Figures 8 and 9. As shown in Figure 8, when the motor shaft is connected to the pump body cavity, the bushing of the motor shaft has an oil groove 3215. However, as shown in Figure 9, when the motor shaft is connected to the pump cover cavity, the bushing of the motor shaft does not have an oil groove. The purpose of this design is to eliminate the oil passage design in the pump cover cavity, reducing the inflow of medium into the pump cover cavity and allowing the medium to flow into the rotor cavity, entering forced convection circulation, thereby achieving further efficient heat dissipation. In the pump body cavity, the medium can pass through the oil groove to form a passage inside the pump body cavity.

[0093] In an optional embodiment, the check valve is interference-fitted with the check valve mounting hole; or, the check valve is threadedly connected to the check valve mounting hole. Correspondingly, the check valve is equipped with a sealing ring; the sealing ring contacts the check valve and the medium exchange port; the sealing ring is used to reinforce the connection between the check valve and the medium exchange port.

[0094] In other words, in some application scenarios, two check valves are designed on the pump cover. The check valves and the pump cover can be designed with threaded connection or interference fit, preferably threaded fit, and are designed with sealing O-rings for easy assembly and maintenance.

[0095] The above are merely optional embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An electric motor pump, characterized in that, The motor pump includes a controller module, a motor module, and a pump module; The controller module is used to send drive signals to the motor module to drive the pump module; The controller module includes a controller housing and controller components; The motor module includes a motor housing and motor components; The pump module includes a pump cover and a pump body; The controller assembly is electrically connected to the motor assembly; The motor assembly is connected to the pump body; The pump body is located inside the motor housing, the pump cover protrudes from the motor housing, and the pump module is coaxially connected to the motor module; The controller housing is stacked with the motor housing; The pump module internally forms a pump cover cavity and a pump body cavity; The pump body and the motor housing form a motor rotor cavity; The pump cover cavity, the pump body cavity, and the motor rotor cavity are used to form a medium passage, through which the medium flows into the motor rotor cavity to achieve forced convection heat transfer.

2. The electric pump according to claim 1, characterized in that, The motor housing and the controller housing are integrated into a single unit. The integrated outer shell forms a first chamber, a second chamber, and a third chamber. The first chamber is used to house the motor assembly and the pump body; The second chamber is used to house the controller assembly; The third chamber is used to house external devices.

3. The electric pump according to claim 2, characterized in that, The motor assembly includes a motor shaft and a motor rotor; The motor shaft passes through the pump body; The motor rotor is connected to the motor shaft and is used to drive the motor shaft; The first end of the motor shaft is connected to the pump body and is used to drive the gear of the pump body; The second end of the motor shaft is used for speed signal excitation.

4. The electric pump according to claim 3, characterized in that, The motor assembly also includes a sliding bearing for supporting a first end of the motor shaft.

5. The electric pump according to claim 3, characterized in that, The motor assembly also includes a shielding sleeve, a sealing ring, and a support ring; The shielding sleeve, the motor coil, and the support ring are located inside the first cavity; The shielding sleeve is used to seal the rotor cavity inside the first chamber; The sealing ring is located at the connection between the shielding sleeve and the pump body and the inner surface of the first chamber. The support ring is used to support the shielding sleeve; Each end of the shielding sleeve has a support ring, wherein the support ring closer to the pump body is encased in plastic within the shielding sleeve.

6. The electric pump according to claim 2, characterized in that, The motor shaft is implemented as a hollow motor shaft; When the motor pump moves, the medium flows from the second end of the motor shaft to the first end of the motor shaft; When the motor shaft is connected to the pump body cavity, the bushing of the motor shaft has an oil groove.

7. The electric pump according to claim 2, characterized in that, The pump module includes a pump cover housing, a medium exchange port, and a one-way valve; The medium exchange port is located at the top of the pump cover housing, and the medium exchange port is used to exchange the medium supplied to the motor pump for operation; When the pump module is working, a high-pressure pump cover cavity and a low-pressure pump cover cavity are formed within the pump module; The one-way valve is used to selectively transport high-pressure medium leaking from the medium passage from the high-pressure pump cover cavity to the low-pressure pump cover cavity.

8. The electric pump according to claim 7, characterized in that, The number of the medium exchange port and the number of the oil port are both 2; The pump cover housing has a one-way valve mounting hole; The one-way valve is located inside the one-way valve mounting hole; The one-way valve mounting hole and the pump cover cavity form a medium passage; The one-way valve is equipped with a one-way valve plug, which is located inside the one-way valve mounting hole.

9. The electric pump according to claim 8, characterized in that, The oil passages formed by the two one-way valve mounting holes are parallel to each other; or, The oil passages formed by the two one-way valve mounting holes form an included angle.

10. The electric pump according to claim 8, characterized in that, The oil passages formed by the two one-way valve mounting holes are parallel to each other; or, The oil passages formed by the two one-way valve mounting holes form an included angle.

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