Electric supercharger with oil leakage prevention and cooling structure

Abstract

The electric supercharger with oil leakage prevention and cooling structure comprises a motor shell, first bearing shell and second bearing shell are arranged on two sides of the motor shell respectively, a motor cavity is arranged in the motor shell, a stator and a rotor are arranged in the motor cavity, a rotating shaft is arranged on the rotor, the rotating shaft penetrates through the motor shell and then penetrates through the first bearing shell and the second bearing shell respectively, a first floating bearing is arranged in the first bearing shell, a sealing ring is arranged on the inner side of the first floating bearing, a second floating bearing is arranged in the second bearing shell, a sealing ring is arranged on the inner side of the second floating bearing, air inlet holes and air outlet holes are arranged on any structure of the motor shell, the first bearing shell and the second bearing shell, and high-pressure gas flows into the air inlet holes. The high-pressure gas circulation structure is adopted, the high-pressure gas environment in the motor rotor cavity is ensured, the lubricating oil can be blocked, the circulating gas can also take away the heat of the rotor, and the purpose of cooling the motor rotor is achieved.

Description

Technical Field

[0001] This invention belongs to the field of electric turbocharger technology, specifically relating to an electric turbocharger with an oil leakage prevention and cooling structure. Background Technology

[0002] A turbocharger is a device used to increase the intake pressure of an engine. It increases the intake density by compressing air or gas, thereby improving engine power and efficiency. Examples include turbochargers and electric superchargers used in automobiles.

[0003] In current electric supercharger structures, when a two-stage electric supercharger uses floating bearings to support the shaft, a sealing ring separates the floating bearing lubrication chamber from the motor rotor chamber to prevent lubricating oil from entering the motor rotor chamber. However, due to gaps in the sealing ring, some lubricating oil can still enter the motor chamber during high-speed shaft rotation, leading to abnormal lubricating oil consumption and affecting the normal operation of the motor.

[0004] In addition, the motor stator has a water cavity for cooling on the outside, but the area between it and the rotor cannot be cooled. Under high load, the motor power may be limited due to excessive temperature.

[0005] Therefore, based on the above situation, this application further designs and improves the relevant structures in the electric turbocharger. Summary of the Invention

[0006] To address the shortcomings of the existing technology, this invention provides an electric booster with an oil-leakage prevention and cooling structure. It adopts a high-pressure gas circulation structure to ensure a high-pressure gas environment in the motor rotor cavity, which can prevent lubricating oil from entering. At the same time, the circulating gas can also carry away the rotor heat, thereby achieving the purpose of cooling the motor rotor.

[0007] The present invention is solved by the following technical solution.

[0008] An electric supercharger with an oil leakage prevention and cooling structure includes a motor housing, with a first bearing housing and a second bearing housing respectively located on both sides of the motor housing; a motor cavity is provided in the motor housing, and a stator and a rotor are provided in the motor cavity; a rotating shaft is located on the rotating shaft, and both ends of the rotating shaft pass through the motor housing and then through the first bearing housing and the second bearing housing respectively; the first bearing housing has a first floating bearing sleeved on the rotating shaft and a corresponding first lubricating oil cavity, and a sealing ring is provided on the inner side of the first floating bearing; the second bearing housing has a second floating bearing sleeved on the rotating shaft and a corresponding second lubricating oil cavity, and a sealing ring is provided on the inner side of the second floating bearing; any one of the structures of the motor housing, the first bearing housing, and the second bearing housing has an air inlet and an air outlet; high-pressure gas flows into the air inlet.

[0009] In a preferred embodiment, an air intake port is provided on the compressor outlet pipe, and the air inlet is connected to the air intake port through a pipe to obtain high-pressure gas, thereby ensuring a high-pressure environment in the motor cavity.

[0010] In a preferred embodiment, a pressure control valve is provided in the pipeline between the air intake port and the air inlet. The pressure control valve controls the intake pressure to ≤1.5 bar. Combined with the function of the sealing ring in the bearing housing, it can prevent a large amount of gas from entering the oil chamber. A small amount of gas can enter the engine housing through the oil return pipe and then be discharged through the torsion pipe.

[0011] In a preferred embodiment, the air inlet is located on the first bearing housing and communicates with the motor cavity; the air outlet is located on the second bearing housing and communicates with the motor cavity.

[0012] Compared with the prior art, the present invention has the following beneficial effects: it provides an electric booster with an oil leakage prevention and cooling structure, adopts a high-pressure gas circulation structure to ensure a high-pressure gas environment in the motor rotor cavity, which can prevent lubricating oil from entering, and at the same time the circulating gas can also carry away the rotor heat, thereby achieving the purpose of cooling the motor rotor. Attached Figure Description

[0013] Figure 1 The three-dimensional representation of the electric booster in this invention Figure 1 .

[0014] Figure 2 The three-dimensional representation of the electric booster in this invention Figure 2 .

[0015] Figure 3 A cross-sectional view of the electric booster in this invention. Figure 1 .

[0016] Figure 4 A cross-sectional view of the electric booster in this invention. Figure 2 .

[0017] Figure 5 A cross-sectional view of the electric booster in this invention. Figure 3 .

[0018] Figure 6 This is a perspective view of the first bearing housing in this invention.

[0019] Figure 7 This is a perspective view of the second bearing housing in this invention. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] In the following embodiments, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0022] In the description of this invention, it should be understood that terms such as center, longitudinal, transverse, length, width, thickness, upper, lower, front, rear, left, right, vertical, horizontal, top, bottom, inner, outer, clockwise, counterclockwise, etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing and simplifying the description of this invention; therefore, they should not be construed as limiting this invention. Furthermore, terms such as first, second, etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features shown. In the description of this invention, unless otherwise expressly specified and limited, terms such as installation, connection, linking, etc., should be interpreted broadly, and those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0023] See Figures 1 to 7 This invention relates to an electric booster with an oil leakage prevention and cooling structure, comprising a motor housing 1, with a first bearing housing 2 and a second bearing housing 3 respectively located on both sides of the motor housing 1; a motor cavity is provided in the motor housing 1, with a stator 11 and a rotor 12 in the motor cavity, and a rotating shaft 12 located on a rotating shaft 8, the two ends of the rotating shaft 8 passing through the motor housing 1 and then passing through the first bearing housing 2 and the second bearing housing 3 respectively; the first bearing housing 2 is provided with a first floating bearing 21 sleeved on the rotating shaft 8 and a corresponding first lubricating oil cavity 22, and a sealing ring 7 is provided on the inner side of the first floating bearing 21; the second bearing housing 3 is provided with a second floating bearing 31 sleeved on the rotating shaft 8 and a corresponding second lubricating oil cavity 32, and a sealing ring 7 is provided on the inner side of the second floating bearing 31; any one of the structures of the motor housing 1, the first bearing housing 2, and the second bearing housing 3 is provided with an air inlet 27 and an air outlet 37; high-pressure gas flows into the air inlet 27.

[0024] Specifically, in this application, an air intake port is provided on the compressor outlet pipe, and the air inlet 27 is connected to this air intake port through a pipe to obtain high-pressure gas, ensuring a high-pressure environment in the motor cavity. A pressure control valve is provided in the pipe between the air intake port and the air inlet 27. This pressure control valve controls the intake pressure to ≤1.5 bar. Combined with the function of the sealing ring in the bearing housing, it can prevent a large amount of gas from entering the oil chamber. A small amount of gas can enter the engine housing through the oil return pipe and then be discharged through the bend pipe.

[0025] Furthermore, in this application, the air inlet 27 is provided on the first bearing housing 2 and communicates with the motor cavity; the air outlet 37 is provided on the second bearing housing 3 and communicates with the motor cavity.

[0026] Specifically, the technical solution of this invention adds an air inlet 27 and an air outlet 37 to the bearing housing and / or motor housing, and adds an air intake port to the pipeline at the outlet of the first-stage compressor. A pressure control valve is added between the air intake port and the motor air inlet to control the intake pressure at ≤1.5 bar. The pressurized gas is introduced into the motor rotor cavity from the motor air inlet, thereby forming a high-pressure cavity in the motor rotor cavity, preventing lubricating oil from entering the motor rotor cavity. At the same time, as the gas flows in the rotor cavity, it can remove the heat from the inner side of the motor stator, avoiding the motor power being limited by temperature.

[0027] During operation, the electric supercharger can reach 10W rpm / min from a standstill within seconds, at which point the pressure ratio can be as low as 1.3, and the internal pressure of the compressor can reach approximately 130 kPa. At this point, only a small amount of splashed lubricating oil accumulates at the sealing ring in the oil chamber. Because the pressure inside the lubricating oil chamber is lower than the gas pressure inside the motor rotor chamber (the normal pressure of lubricating oil in the oil chamber is -3 to 4 kPa), the gas, under the action of the pressure difference, pushes the accumulated lubricating oil at the sealing ring back into the lubricating oil chamber, preventing lubricating oil leakage. By combining air pressure and the sealing ring, the entry of lubricating oil into the motor chamber can be essentially prevented during the operation of the electric supercharger, thus avoiding abnormal lubricating oil consumption. Since no lubricating oil enters the motor chamber during motor operation, the motor safety is higher when a high-voltage platform (such as an 800V voltage platform) is used.

[0028] The air inlet 27 and the air outlet 37 are located on both sides of the motor stator. During the gas flow process, the high temperature inside the motor stator can be carried away, reducing the motor stator temperature. As the motor speed increases, the stator temperature increases, and the compressor end pressure further increases, which can simultaneously improve the air cooling efficiency.

[0029] As can be seen from the above description, the present invention provides an electric booster with an oil leakage prevention and cooling structure. It adopts a high-pressure gas circulation structure to ensure a high-pressure gas environment in the motor rotor cavity, which can prevent lubricating oil from entering. At the same time, the circulating gas can also carry away the rotor heat, thereby achieving the purpose of cooling the motor rotor.

[0030] The scope of protection of this invention includes, but is not limited to, the above embodiments. The scope of protection of this invention is defined by the claims. Any substitutions, modifications, or improvements to this technology that are easily conceived by those skilled in the art fall within the scope of protection of this invention.

Claims

1. An electric booster with an oil leak prevention and cooling structure, comprising a motor housing (1), wherein a first bearing housing (2) and a second bearing housing (3) are respectively provided on both sides of the motor housing (1). The motor housing (1) is provided with a motor cavity, and the motor cavity is provided with a stator (11) and a rotor (12). The rotor (12) is located on the rotating shaft (8). The two ends of the rotating shaft (8) pass through the motor housing (1) and then pass through the first bearing housing (2) and the second bearing housing (3) respectively. Its features are: The first bearing housing (2) is provided with a first floating bearing (21) sleeved on the rotating shaft (8) and a corresponding first lubricating oil cavity (22). The inner side of the first floating bearing (21) is provided with a sealing ring (7). The second bearing housing (3) is provided with a second floating bearing (31) sleeved on the rotating shaft (8) and a corresponding second lubricating oil cavity (32). The inner side of the second floating bearing (31) is provided with a sealing ring (7). The motor housing (1), the first bearing housing (2), and the second bearing housing (3) are provided with an air inlet (27) and an air outlet (37); high-pressure gas flows into the air inlet (27); An air intake port is provided on the compressor outlet pipeline, and the air inlet (27) is connected to the air intake port through a pipeline to obtain high-pressure gas; A pressure control valve is installed in the pipeline between the air intake port and the air inlet (27), which controls the air intake pressure to ≤1.5 bar; The air inlet (27) is located on the first bearing housing (2) and connected to the motor cavity; the air outlet (37) is located on the second bearing housing (3) and connected to the motor cavity; The gas pressure inside the motor cavity is higher than the pressure inside the first lubricating oil cavity (22) and the second lubricating oil cavity (32). Under the action of the pressure difference, the gas pushes the lubricating oil accumulated at the sealing ring (7) back to the corresponding lubricating oil cavity.

2. The electric booster with an oil leakage prevention and cooling structure according to claim 1, characterized in that, The air inlet (27) and the air outlet (37) are located on both sides of the stator (11).

3. The electric booster with an oil leakage prevention and cooling structure according to claim 1, characterized in that, The pressure of the lubricating oil in the first lubricating oil chamber (22) and the second lubricating oil chamber (32) under normal conditions is -3~4 kPa.

4. The electric booster with an oil leakage prevention and cooling structure according to claim 1, characterized in that, It is equipped with an oil return pipe. A small amount of gas enters the engine housing through the oil return pipe and is then discharged through a bend pipe.

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