An electric oil pump assembly for oil cooling of motor and controller

Abstract

The present invention discloses an electric oil pump assembly for oil cooling a motor and a controller, comprising a rotor group, an oil inlet and an oil outlet, wherein the rotor group consists of an inner rotor and an outer rotor, the motor is placed above a mechanical oil pump, the motor comprises a stator assembly, a rotor assembly and a motor housing, the stator assembly is placed in the motor housing, the rotor assembly is placed in the stator assembly, the controller is placed on the motor, the controller comprises a controller housing, the controller housing has a bottom end surface, the cooling oil circuit comprises a first oil channel, a second oil channel, a third oil channel, a fourth oil channel and a fifth oil channel, and the outlet of the cooling oil circuit A is communicated with the oil inlet; the present invention eliminates the rotating oil seal for dynamic sealing on the drive shaft of the electric oil pump module, which not only reduces the cost of the entire system, but also reduces the friction power loss between the oil seal and the shaft, improves the mechanical efficiency of the electric oil pump, and also improves the service life of the electric oil pump.

Description

Technical Field

[0001] The present invention relates to an electric oil pump, in particular to an electric oil pump assembly for oil cooling a motor and a controller, belonging to the technical field of automobile parts. Background Art

[0002] The electric oil pump works for a long time in the car, which requires the electric oil pump to have high operating reliability and long service life, as well as good working efficiency and high power density.

[0003] The mainstream layout structure of electric oil pumps currently on the market includes a mechanical oil pump, a motor and a controller integrated into an overall module structure, in which the mechanical oil pump is arranged at the front end, the motor is arranged in the middle, and the controller is arranged at the rear end. The electric oil pump is directly driven by the motor through the shaft. Generally, a rotating oil seal is installed between the drive shaft and the corresponding shaft hole to isolate the oil in the mechanical oil pump from entering the motor. The friction between the drive shaft and the rotating oil seal will cause power loss and reduce the mechanical efficiency of the electric oil pump. During use, the rubber parts on the rotating oil seal will wear and there is a risk of leakage, which also limits the service life of the electric oil pump.

[0004] Furthermore, because electric oil pumps are typically mounted on the engine or transmission, the ambient temperature can be very high. When the electric oil pump is mounted outside the engine or transmission housing, the motor essentially relies on heat conduction from the metal casing to dissipate heat, while the controller dissipates heat primarily through natural convection via the heat dissipation ribs on its rear end. In actual operation, a car sometimes requires the electric oil pump to input high currents to deliver high power and oil pressure, which quickly generates significant heat in the motor and controller, causing a rapid temperature increase. The higher the temperature, the greater the impact on the motor and controller's operating efficiency. Excessive temperatures can even cause the motor and controller to burn out, shortening the electric oil pump's service life. Summary of the Invention

[0005] The purpose of the present invention is to address the shortcomings of the existing technology and provide an electric oil pump, which eliminates the rotating oil seal structure inside the pump, adds an oil circuit structure for active cooling of the motor and controller, reduces the cost of the entire system, and reduces the friction power loss between the oil seal and the shaft.

[0006] To achieve the above-mentioned objectives, the present invention provides an electric oil pump assembly for oil cooling a motor and a controller, comprising a mechanical oil pump, wherein the mechanical oil pump includes a rotor group, an oil inlet and an oil outlet, and the rotor group consists of an inner rotor and an outer rotor; a motor, wherein the motor is placed above the mechanical oil pump, the motor includes a stator assembly, a rotor assembly and a motor housing, the stator assembly is placed in the motor housing, the rotor assembly is placed in the stator assembly, and the rotor assembly includes a drive shaft; a controller, wherein the controller is placed on the motor, the controller includes a controller housing, and the controller housing has a bottom end surface; a cooling oil circuit, wherein the cooling oil circuit includes a first oil channel, a second oil channel, a third oil channel, a fourth oil channel and a fifth oil channel, and the outlet of the cooling oil circuit is connected to the oil inlet.

[0007] As a further improvement of the above solution, the oil inlet and the oil outlet are arranged on the bottom end surface or side surface of the mechanical oil pump.

[0008] As a further improvement of the above solution, the stator assembly has an upper end surface, a lower end surface, and an inner surface. The inner side of the stator assembly is provided with multiple inner oil grooves, and the outer side thereof is provided with multiple outer oil grooves, and the outer oil grooves form a fifth oil channel.

[0009] As a further improvement of the above scheme, the rotor assembly also includes a first rolling bearing and a second rolling bearing arranged at both ends of the drive shaft, a rotor silicon steel sheet arranged between the first rolling bearing and the second rolling bearing, a magnet and an oil groove arranged in the rotor silicon steel sheet, the first rolling bearing is placed on the side close to the mechanical oil pump, and the gap inside the first rolling bearing forms a second oil channel.

[0010] As a further improvement of the above solution, the magnets and the oil grooves are both provided in plurality and are arranged in a ring shape, and the oil grooves are arranged on the inner side of the magnets.

[0011] As a further improvement of the above solution, the drive shaft is connected to the inner rotor by one of a flat drive connection, an interference fit connection, a spline connection and a keyway connection.

[0012] As a further improvement of the above solution, an oil return hole and a shaft hole are opened on the motor housing, the oil return hole is connected to the cooling oil circuit, and the motor housing has an inner end surface and an inner wall.

[0013] As a further improvement of the above solution, the shaft hole is matched with the drive shaft, and the gap between the outer circle of the drive shaft and the shaft hole forms a first oil channel.

[0014] As a further improvement of the above solution, the air gap between the stator assembly and the rotor assembly, the inner oil groove, and the oil groove inside the rotor assembly are arranged in parallel to form a third oil channel.

[0015] As a further improvement of the above solution, a fourth oil channel is formed in the gap between the upper end surface of the stator assembly and the bottom end surface of the controller housing.

[0016] The beneficial effects of the present invention are as follows: the electric oil pump assembly that oil-cools the motor and controller eliminates the rotary oil seal used for dynamic sealing on the drive shaft of the electric oil pump module, thereby reducing the cost of the entire system and reducing the frictional power loss between the oil seal and the shaft, thereby improving the mechanical efficiency of the electric oil pump and also extending the service life of the electric oil pump.

[0017] The oil leaked from the mechanical oil pump is drawn out from the gap between the shaft and the shaft hole, flows through the active cooling oil circuit, and then returns to the oil suction chamber of the mechanical oil pump. In the process of flowing through the active cooling oil circuit, the oil contacts the internal end faces of the motor stator assembly, motor rotor assembly and controller, and takes away the heat generated by the motor and controller during operation, which can effectively reduce the temperature rise of the motor and controller, thereby improving the working efficiency and power density of the motor and controller, reducing the size of the motor and controller, and reducing the cost; it also improves the volumetric efficiency of the electric oil pump to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a perspective view of an electric oil pump assembly for oil cooling a motor and a controller provided in an embodiment of the present invention;

[0019] Figure 2 This is a front view of an electric oil pump assembly for oil cooling a motor and a controller provided by an embodiment of the present invention;

[0020] Figure 3 yes Figure 2 Cross-sectional view along the AA axis;

[0021] Figure 4 is a structural diagram of the stator assembly;

[0022] Figure 5 It is another structural schematic diagram of the stator assembly;

[0023] Figure 6 is a schematic diagram of the structure of the rotor assembly;

[0024] Figure 7 It is a structural diagram of the rotor group in the mechanical oil pump;

[0025] Figure 8 It is a schematic diagram of the internal structure of the motor housing;

[0026] Figure 9 It is a structural diagram of the controller housing.

[0027] The markings of the various components in the accompanying drawings are as follows:

[0028] 100-mechanical oil pump; 110-rotor assembly; 111-inner rotor; 112-outer rotor; 120-oil inlet; 130-oil outlet;

[0029] 200 - motor; 210 - stator assembly; 211 - upper end surface; 212 - lower end surface; 213 - inner surface; 214 - inner oil tank; 215 - outer oil tank; 220 - rotor assembly; 221 - drive shaft;

[0030] 222 - first rolling bearing; 223 - rotor silicon steel sheet; 224 - magnet; 225 - oil tank;

[0031] 226 - second rolling bearing; 230 - motor housing; 231 - oil return hole; 232 - shaft hole;

[0032] 233-inner end surface; 234-inner wall;

[0033] 300 - controller; 310 - controller housing; 311 - bottom end surface. DETAILED DESCRIPTION

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present invention.

[0035] Example

[0036] like Figures 1 to 9 As shown, the present invention discloses an electric oil pump assembly for oil cooling of a motor and a controller, wherein the traditional rotary oil seal structure is eliminated and a cooling oil circuit A is added. The assembly includes a mechanical oil pump 100, a motor 200, a controller 300 and a cooling oil circuit A.

[0037] Specifically, the mechanical oil pump 100 includes a rotor group 110, an oil inlet 120 and an oil outlet 130, the rotor group 110 is composed of an inner rotor 111 and an outer rotor 112, the motor 200 is placed above the mechanical oil pump 100, the motor 200 includes a stator assembly 210, a rotor assembly 220 and a motor housing 230, the stator assembly 210 is placed in the motor housing 230, the rotor assembly 220 is placed in the stator assembly 210, the controller 300 is placed on the motor 200, the controller 300 includes a controller housing 310, the controller housing 310 has a bottom end surface 311, the cooling oil circuit A includes a first oil channel, a second oil channel, a third oil channel, a fourth oil channel and a fifth oil channel, and the outlet of the cooling oil circuit A is connected to the oil inlet 120.

[0038] In this embodiment, the positions of the oil inlet 120 and the oil outlet 130 can be adjusted according to the structural design of the engine or gearbox in actual use. Figure 1 As shown, it is placed on the bottom end surface of the mechanical oil pump 100 , but it can also be placed on the side of the mechanical oil pump 100 .

[0039] In this embodiment, the stator assembly 210 has an upper end surface 211, a lower end surface 212, and an inner surface 213. A plurality of inner oil grooves 214 are provided on the inner side of the stator assembly 210, and a plurality of outer oil grooves 215 are provided on the outer side thereof. The outer oil grooves 215 form a fifth oil channel. In actual application, it is also possible to choose to cancel the multiple outer oil grooves 215 of the motor stator assembly 210, and make multiple oil grooves on the inner wall 234 of the stator assembly 210 mounted by the motor housing 230 to replace the outer oil grooves 215 to form the fifth oil channel.

[0040] Preferably, the air gap between the stator assembly 210 and the rotor assembly 220, the inner oil groove 214 and the oil groove 225 inside the rotor assembly 220 form a third oil channel in parallel, and the gap between the upper end surface 211 of the stator assembly 210 and the bottom end surface 311 of the controller housing 310 forms a fourth oil channel. In actual application, the inner oil groove 214 and the oil groove 225 inside the rotor assembly 220 can also be eliminated, and only the air gap between the stator assembly 210 and the rotor assembly 220 is retained as the third oil channel.

[0041] In this embodiment, the rotor assembly 220 also includes a first rolling bearing 222 and a second rolling bearing 226 arranged at both ends of the drive shaft 221, a rotor silicon steel sheet 223 arranged between the first rolling bearing 222 and the second rolling bearing 226, a magnet 224 and an oil groove 225 arranged in the rotor silicon steel sheet 223, and the first rolling bearing 222 is placed on the side close to the mechanical oil pump 100. The gap inside the first rolling bearing 222 forms a second oil channel. In actual applications, the first rolling bearing 222 can also be eliminated and replaced by a sliding bearing bushing, or a hole can be directly machined on the motor housing 230 as an axial diameter support for the drive shaft 221.

[0042] Preferably, the magnets 224 and the oil grooves 225 are provided in plurality and are arranged in an annular shape, the oil grooves 225 are provided on the inner side of the magnets 224, the drive shaft 221 is connected to the inner rotor 111, the drive shaft (221) and the inner rotor 111 run at the same speed, and the connection method is one of a flat drive connection, an interference fit connection, a spline connection and a key connection, and is not limited to the above-mentioned connection methods. In actual application, a suitable connection method can be selected according to the requirements of the enterprise.

[0043] In this embodiment, an oil return hole 231 and a shaft hole 232 are provided on the motor housing 230. The oil return hole 231 is connected to the cooling oil circuit A. The motor housing 230 has an inner end face 233 and an inner wall 234. The shaft hole 232 is matched with the drive shaft 221. The gap between the outer circle of the drive shaft 221 and the shaft hole 232 forms a first oil channel.

[0044] According to the electric oil pump assembly for oil cooling of the motor and controller described in the above embodiment, its working principle is: the electric oil pump draws oil from the oil tank of the engine or transmission through the oil inlet 120, drives the rotor group 110 of the mechanical oil pump 100 to rotate through the drive shaft 221 on the rotor assembly 220, and after the rotor group 110 does work on the oil, the oil is pumped back to the engine or transmission from the oil outlet 130.

[0045] The circuit diagram of the oil circuit A for active cooling of the motor 200 and the controller 300 inside the electric oil pump is as follows: when the mechanical oil pump is working, the oil leaked from the end face flows out from the gap between the outer circle of the drive shaft 221 and the corresponding shaft hole 232, that is, flows in from the first oil channel, and then flows through the second oil channel, that is, the gap inside the first rolling bearing 222, and then flows through the air gap between the stator assembly 210 and the rotor assembly 220, the inner oil groove 214 in the stator assembly 210 and the multi-channel oil grooves 225 in the rotor assembly 220, and then passes through the gap between the bottom end face 311 of the controller housing 310 and the upper end face 211 of the stator assembly 210, and then flows out through the multi-channel outer oil grooves 215 on the outside of the stator assembly 210, that is, the fifth oil channel, and finally flows back to the oil suction chamber of the mechanical oil pump 100 through the return oil hole 231 on the motor housing 230.

[0046] In addition, in actual applications, the lower end face 212 of the stator assembly 210 and the inner end face 233 of the motor housing 230 must be tightly sealed to each other to prevent the oil from flowing out of the gap inside the first rolling bearing 222 and directly flowing from there to the return oil hole 231 and back to the oil suction chamber of the mechanical oil pump 100.

[0047] In summary, the use of the electric oil pump assembly for oil cooling the motor and controller in the above embodiment eliminates the rotating oil seal used for dynamic sealing on the drive shaft of the electric oil pump module, which not only reduces the cost of the entire system, but also reduces the frictional power loss between the oil seal and the shaft, improves the mechanical efficiency of the electric oil pump, and also increases the service life of the electric oil pump.

[0048] The oil leaked from the mechanical oil pump is drawn out from the gap between the shaft and the shaft hole, flows through the active cooling oil circuit, and then returns to the oil suction chamber of the mechanical oil pump. In the process of flowing through the active cooling oil circuit, the oil contacts the internal end faces of the motor stator assembly, motor rotor assembly and controller, and takes away the heat generated by the motor and controller during operation, which can effectively reduce the temperature rise of the motor and controller, thereby improving the working efficiency and power density of the motor and controller, reducing the size of the motor and controller, and reducing the cost; it also improves the volumetric efficiency of the electric oil pump to a certain extent.

[0049] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0050] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. An electric oil pump assembly for oil cooling a motor and a controller, characterized by: include, A mechanical oil pump (100), comprising a rotor assembly (110), an oil inlet (120), and an oil outlet (130), wherein the rotor assembly (110) is composed of an inner rotor (111) and an outer rotor (112); A motor (200), the motor (200) being placed above the mechanical oil pump (100), the motor (200) comprising a stator assembly (210), a rotor assembly (220) and a motor housing (230), the stator assembly (210) being placed in the motor housing (230), the rotor assembly (220) being placed in the stator assembly (210), and the rotor assembly (220) comprising a drive shaft (221); A controller (300), the controller (300) being placed on the motor (200), the controller (300) comprising a controller housing (310), the controller housing (310) having a bottom end surface (311); A cooling oil circuit (A), the cooling oil circuit (A) comprising a first oil channel, a second oil channel, a third oil channel, a fourth oil channel and a fifth oil channel, the outlet of the cooling oil circuit (A) being in communication with an oil inlet (120); The stator assembly (210) has an upper end surface (211), a lower end surface (212), and an inner surface (213); a plurality of inner oil grooves (214) are provided on the inner side of the stator assembly (210); a plurality of outer oil grooves (215) are provided on the outer side thereof; the outer oil grooves (215) form fifth oil channels; The rotor assembly (220) further includes a first rolling bearing (222) and a second rolling bearing (226) disposed at both ends of the drive shaft (221), a rotor silicon steel sheet (223) disposed between the first rolling bearing (222) and the second rolling bearing (226), a magnet (224) and an oil groove (225) disposed within the rotor silicon steel sheet (223), the first rolling bearing (222) being disposed on a side close to the mechanical oil pump (100), and a gap within the first rolling bearing (222) forming a second oil channel; The motor housing (230) is provided with an axial hole (232), the axial hole (232) is matched with the drive shaft (221), and the gap between the outer circle of the drive shaft (221) and the axial hole (232) forms a first oil channel; The air gap between the stator assembly (210) and the rotor assembly (220), the inner oil groove (214), and the oil groove (225) inside the rotor assembly (220) are arranged in parallel to form a third oil channel; A fourth oil channel is formed in the gap between the upper end surface (211) of the stator assembly (210) and the bottom end surface (311) of the controller housing (310).

2. The electric oil pump assembly for oil cooling a motor and a controller according to claim 1, characterized in that: The oil inlet (120) and the oil outlet (130) are arranged on the bottom end surface or side surface of the mechanical oil pump (100).

3. The electric oil pump assembly for oil cooling a motor and a controller according to claim 1, characterized in that: The magnets (224) and the oil grooves (225) are both provided in plurality and are arranged in a ring shape, and the oil grooves (225) are arranged on the inner side of the magnets (224).

4. The electric oil pump assembly for oil cooling a motor and a controller according to claim 1, characterized in that: The drive shaft (221) is connected to the inner rotor (111) in a connection manner of one of a flat drive connection, an interference fit connection, a spline connection, and a key connection.

5. The electric oil pump assembly for oil cooling a motor and a controller according to claim 1, characterized in that: An oil return hole (231) is provided on the motor housing (230), and the oil return hole (231) is connected to the cooling oil circuit (A). The motor housing (230) has an inner end surface (233) and an inner wall (234).

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