Lubricating and cooling system of distributed electric driving device

Abstract

The utility model relates to a lubricating and cooling system of a distributed electric driving device, the distributed electric driving device comprises a first motor shell, a first speed reducer shell, a middle shell, a second speed reducer shell and a second motor shell, a speed reduction transmission device is accommodated in the speed reducer shell, the middle shell provides support for the speed reduction transmission device, and the second motor shell is connected with the second speed reducer shell. The lubricating and cooling system comprises a first subsystem and a second subsystem, the first subsystem and the second subsystem are the same in structure, the first subsystem comprises a first oil way, and the first oil way is connected to the oil cooler connector and comprises a first oil outlet hole; and the second oil way is connected to the oil cooler connecting port and comprises a plurality of branch oil ways. The utility model provides the lubricating and cooling system for the distributed double-motor electric drive, the system consists of two independent lubricating oil paths, and oil supply for each part of the distributed electric drive device is realized through reasonable arrangement of the oil paths, so that corresponding lubricating and cooling are realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of vehicles, and in particular relates to a lubrication and cooling system of a distributed electric drive device. Background Art

[0002] The lubrication and cooling system is an important system on the vehicle. One known solution is to set up an electronic pump and a mechanical pump in the vehicle at the same time, and use the electronic pump or the mechanical pump or both to provide the oil required for lubrication and cooling according to the different operating conditions of the vehicle. For distributed electric drive devices, it is necessary to provide lubrication and cooling for multiple motors and the associated reducers at the same time, which requires the development of targeted lubrication and cooling systems. At present, this type of lubrication and cooling system mostly uses a common oil cooling circuit to cool and lubricate the oil-cooled motors and reducers on both sides. The system consists of an electric pump and a mechanical pump, a suction filter, and several valves of the oil cooler. The lubricating oil flows from the intermediate housing to the reducers and motors on both sides to lubricate and cool the corresponding bearings, gear pairs, and motor stators and rotors.

[0003] However, this solution has the following disadvantages:

[0004] (1) Due to the different heating points of the motor and the reducer, the combination of an electric pump and a mechanical pump cannot cover all cooling and lubrication conditions well. For example, the motor generates more heat under high torque, while the reducer generates more heat under high speed. Therefore, under low speed and high torque conditions, the mechanical pump cannot provide sufficient flow to cool and lubricate the motor. Therefore, a larger power electronic pump is required. Under high speed and low torque conditions, the mechanical pump will output more flow, resulting in reduced system efficiency.

[0005] (2) Since the motors on both sides share the same housing oil cavity, the housing cavity will be larger. In order to prevent the oil pump from sucking air under tilting conditions, a larger amount of oil needs to be added, which increases the weight and cost of the whole machine. In addition, under left and right tilting conditions, the oil will flow into the motor housing on one side due to the tilt, covering the stator and rotor air gap and affecting the motor efficiency.

[0006] (3) Under normal operating conditions, due to the increase in the amount of oil added, the oil stirring loss inside the reducer increases, thereby increasing the heat generated by the entire machine and reducing the efficiency of the entire machine. Utility Model Content

[0007] Based on the applicant's research and practical experience in this field, the following improved technical solutions are proposed here.

[0008] A lubrication and cooling system for a distributed electric drive device, the distributed electric drive device includes a first motor housing, a first reducer housing, an intermediate housing, a second reducer housing and a second motor housing, the motor housing accommodates a stator assembly and a rotor assembly, the reducer housing accommodates a reduction transmission device, and the intermediate housing provides support for the reduction transmission device, the lubrication and cooling system includes a first subsystem and a second subsystem, the first subsystem and the second subsystem have the same structure, the first subsystem includes: a first oil circuit, the first oil circuit is connected to the oil cooler connection port and includes a first oil outlet hole; a second oil circuit, the second oil circuit is connected to the oil cooler connection port and includes a plurality of branch oil circuits. The utility model proposes a lubrication and cooling system for a distributed dual-motor electric drive, the system consists of two independently distributed lubrication oil circuits, and through the reasonable setting of the oil circuits, the oil supply to each component of the distributed electric drive device is realized to achieve corresponding lubrication and cooling.

[0009] As a feasible preferred solution of the utility model, the first oil circuit includes an oil circuit arranged on the intermediate housing, and the first oil circuit includes a first oil outlet hole for providing oil to the output shaft gear pair, the intermediate shaft and the bearing of the output shaft of the reduction transmission device.

[0010] As a feasible preferred solution of the utility model, the second oil circuit includes a first branch oil circuit, the first branch oil circuit includes an oil circuit arranged on the intermediate housing, and includes a second oil outlet hole for providing oil to the input shaft gear pair of the reduction transmission device.

[0011] As a feasible preferred scheme of the utility model, the second oil circuit includes a second branch oil circuit, the second branch oil circuit is provided with three oil outlet holes, and the second branch oil circuit includes an oil circuit arranged on the intermediate housing and an oil circuit on the reducer housing, and the three oil outlet holes are respectively used to provide oil for cooling the stator core and the winding.

[0012] As a feasible preferred solution of the utility model, the second oil circuit includes a third branch oil circuit, the third branch oil circuit includes an oil circuit located on the intermediate housing, and the third branch oil circuit is provided with oil supplied to the input shaft bearing of the reduction transmission device.

[0013] As a feasible preferred solution of the utility model, the third branch oil circuit is connected to an oil guide pipe, and the oil guide pipe fluid is connected to an oil slinger arranged on the hollow motor shaft, so as to provide oil for the motor rotor.

[0014] As a feasible preferred solution of the present utility model, the first subsystem also includes a filter, an electric pump and an oil cooler.

[0015] From the above, it can be seen that by setting up two electric pumps, suction filters and oil coolers, and independently distributing the oil cooling circuits from the intermediate housing to the reduction gearboxes on both sides, the bearings, gear pairs and motor stators and rotors on both sides are lubricated and cooled respectively. This system has a simple working principle, can ensure the normal temperature of the electric drive assembly, improve transmission efficiency and extend service life.

[0016] Other features and advantages of the present invention will be further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Exemplary embodiments of the present invention are described with reference to the accompanying drawings, in which:

[0018] Figure 1 A front view of a distributed electric drive device according to the utility model is shown.

[0019] Figure 2 The structure of the lubrication and cooling system used in the distributed electric drive device of the utility model is shown.

[0020] Figure 3 The oil circuit schematic diagram of the lubrication and cooling system of the utility model is shown.

[0021] The same reference numerals in different drawings denote the same elements. DETAILED DESCRIPTION

[0022] Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, many specific details are set forth so that those skilled in the art can more fully understand and implement the present invention. However, it is obvious to those skilled in the art that the implementation of the present invention may not have some of these specific details. In addition, it should be understood that the present invention is not limited to the specific embodiments described. On the contrary, any combination of the features and elements described below may be considered to implement the present invention, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments and advantages are for illustrative purposes only and should not be regarded as features or limitations of the claims unless clearly stated in the claims.

[0023] In the following description, the descriptions about directions, such as "upper", "lower", "inner", "outer", "radial", "axial", etc., which may be used, are only for the convenience of description, unless otherwise specified, and are not intended to form any limitation on the technical solution of the utility model. In addition, in the following description, terms such as "first", "second", etc. are used to describe the elements of the present application, and these terms are only used to distinguish the elements, and are not intended to limit the nature, sequence, order or number of these elements.

[0024] Figure 1FIG. 2 shows a front view of a distributed electric drive device according to the utility model. Figure 1 As can be seen in the figure, the distributed electric drive assembly includes the first motor housing 1 on the left, the first reducer housing 2, the second reducer housing 4 on the right, the second motor housing 5 and the reducer housing 3 in the middle. Each motor housing contains a corresponding motor, and each reducer housing contains a corresponding reducer. The middle housing 3 serves as a partition housing to provide support for the components in the reducers on both sides. Figure 1 When the distributed electric drive assembly shown is installed on a vehicle, it can drive two wheels at the same time, thereby achieving independent driving of the two wheels.

[0025] from Figure 1 It can also be seen that in order to provide the oil required for lubrication and cooling to the electric drive device on each side, a first oil cooler 6 and a first electric pump 7 are provided on the left side, and a second electric pump 8 and a second oil cooler 9 are provided on the right side.

[0026] In addition, oil passages for oil flow are distributed on each reducer housing, motor housing and intermediate housing. The oil flowing out of the oil cooler flows through these oil passages and will be discussed in detail below. Figure 2 The oil circuits included in the described system are used to supply oil to various parts. Figure 2 The oil circuit shown may or may not include the oil circuits in the various housings described above.

[0027] Figure 2 The structure of the lubrication and cooling system used in the distributed electric drive assembly of the utility model is shown. Figure 1 Similarly, the lubrication and cooling system consists of two subsystems to provide lubrication and cooling for the electric drive devices on both sides respectively. Figure 2 Only the left-hand components are provided with reference numerals. Figure 2 It can be seen that the oil circuit on the left side includes an oil cooler connection port 11, which is connected to the oil cooler and is used to receive oil from the oil cooler. From the oil cooler connection port 11, the oil circuit is divided into a first oil circuit and a second oil circuit. The first oil circuit is partially located on the intermediate housing 3 and is provided with a first oil outlet 12. The oil is sprayed from the first oil outlet 12 to the oil collecting tank, and then can flow to each gear pair and the corresponding bearing through the corresponding oil circuit, for example, it can flow to the output shaft gear pair, the intermediate shaft and the output shaft bearing.

[0028] The second oil circuit includes three branch oil circuits, namely, the first branch oil circuit, the second branch oil circuit and the third branch oil circuit. The first branch oil circuit is also partially located on the intermediate housing 3, and a second oil outlet hole 13 is opened thereon, and the oil leaves the oil circuit at the second oil outlet hole 13 to lubricate the corresponding components, for example, the input shaft gear pair can be lubricated. The second branch oil circuit flows in the direction of the motor, and three oil outlet holes are arranged on the second branch oil circuit, namely, the third oil outlet hole 14-1, the fourth oil outlet hole 14-2 and the fifth oil outlet hole 14-3. As an example, the oil flowing out of the third oil outlet hole 14-1 has previously flowed through the oil circuit on the intermediate housing 3 and the oil circuit on the reducer housing in sequence, and the third oil outlet hole 14-1 can be arranged on the reducer, and when the oil flows out from here, it can be used to lubricate and cool, for example, the winding of the motor; the fourth oil outlet hole 14-2 and the fifth oil outlet hole 14-3 can be located on the motor housing, respectively used to cool the stator core and the winding.

[0029] The third branch oil circuit includes an oil circuit located on the intermediate housing, and a sixth oil outlet hole 15 is arranged on the third branch oil circuit. The oil flowing out of the oil outlet hole can lubricate the input shaft bearing on the reducer side. In addition, the third branch oil circuit is also connected to the oil guide pipe 16, and the oil guide pipe 16 is fluidically connected to the motor shaft 18. Oil slingers 17 are arranged on both sides of the motor shaft 18, and the motor shaft 18 can be arranged as a hollow shaft so as to form an oil circuit inside. A fluid channel is arranged at the part where the motor shaft 18 is connected to the oil slinger 17, so that the oil can enter the oil slinger 17 from the motor shaft. There are multiple small holes on the oil slinger 17, and the oil is evenly applied to the motor rotor through them.

[0030] Figure 3 The oil circuit schematic diagram of the lubrication and cooling system of the utility model is shown. Figure 3 It can be seen that after the oil tank, there are filters, electric pumps and oil coolers, and then the oil circuit is combined with the above. Figure 2 The oil is then branched out through the various branches and oil outlet holes shown in the figure to reach various parts that require lubrication and cooling. The oil will eventually flow back to the oil pan.

[0031] It can be seen that the utility model proposes a lubrication and cooling system for distributed dual-motor electric drive, which is composed of two independent lubrication oil circuits. Through the reasonable setting of the oil circuits, the oil supply to each component of the distributed electric drive device is realized to achieve corresponding lubrication and cooling. The system is composed of two electric pumps, a suction filter and an oil cooler. The oil cooling circuits from the intermediate housing to the reduction boxes on both sides are independently distributed to lubricate and cool the bearings, gear pairs and motor stators and rotors on both sides. The working principle of this system is simple, which can ensure the normal temperature of the electric drive assembly, improve the transmission efficiency and extend the service life. Through the independent design of the oil cooling circuit, the liquid level is lowered and the work efficiency is improved; when the vehicle tilts left or right, due to the small amount of oil added, less oil is collected on the motor side, which improves the motor efficiency.

[0032] The above description is merely an exemplary embodiment of the spirit and principle of the present invention. It will be appreciated by those skilled in the art that various changes may be made to the described examples without departing from the spirit and principle, and these changes and their various equivalents are anticipated by the applicant and fall within the scope defined by the claims of the present invention.

Claims

1. A lubrication and cooling system for a distributed electric drive device, the distributed electric drive device comprising a first motor housing (1), a first reducer housing (2), an intermediate housing (3), a second reducer housing (4) and a second motor housing (5), wherein the motor housing accommodates a stator assembly and a rotor assembly, the reducer housing accommodates a reduction transmission device, and the intermediate housing provides support for the reduction transmission device, characterized in that: The lubrication cooling system comprises a first subsystem and a second subsystem, the first subsystem and the second subsystem having the same structure, the first subsystem comprising: a first oil circuit, the first oil circuit being connected to an oil cooler connection port (11) and comprising a first oil outlet hole (12); and a second oil circuit, the second oil circuit being connected to the oil cooler connection port (11) and comprising a plurality of branch oil circuits.

2. The lubrication and cooling system of the distributed electric drive device according to claim 1, characterized in that: The first oil circuit comprises an oil circuit arranged on an intermediate housing, and the first oil circuit comprises a first oil outlet hole (12) for providing oil to the output shaft gear pair, the intermediate shaft and the bearing of the output shaft of the reduction transmission device.

3. The lubrication and cooling system of a distributed electric drive device according to claim 1 or 2, characterized in that: The second oil circuit comprises a first branch oil circuit, the first branch oil circuit comprises an oil circuit arranged on the intermediate housing, and comprises a second oil outlet hole (13) for providing oil to the input shaft gear pair of the reduction transmission device.

4. The lubrication and cooling system of a distributed electric drive device according to claim 1 or 2, characterized in that: The second oil circuit includes a second branch oil circuit, which is provided with three oil outlet holes. The second branch oil circuit includes an oil circuit provided on the intermediate housing and an oil circuit on the reducer housing. The three oil outlet holes are respectively used to provide oil for cooling the stator core and the winding.

5. The lubrication and cooling system of a distributed electric drive device according to claim 1 or 2, characterized in that: The second oil circuit includes a third branch oil circuit, the third branch oil circuit includes an oil circuit located on the intermediate housing, and the third branch oil circuit is provided with oil supplied to the input shaft bearing of the reduction transmission device.

6. The lubrication and cooling system of the distributed electric drive device according to claim 5, characterized in that: The third branch oil passage is connected to an oil guide pipe (16), and the oil guide pipe (16) is fluidically connected to an oil slinger (17) disposed on a hollow motor shaft (18), thereby providing oil for the motor rotor.

7. The lubrication and cooling system of a distributed electric drive device according to claim 1 or 2, characterized in that: The first subsystem also includes a filter, an electric pump (7) and an oil cooler (6).

Images