Electric petrol pump

Abstract

The utility model discloses an electric refueling pump, which belongs to the technical field of refueling pumps and comprises a pump body, an oil inlet pipeline, an oil outlet pipeline and an oil return pipeline, the oil inlet pipeline is connected with an oil inlet of the pump body, the oil outlet pipeline is connected with an oil outlet of the pump body, and a one-way valve for preventing oil from flowing back is arranged in the oil outlet pipeline. The oil pump is characterized in that one end of the oil return pipeline is communicated with the oil outlet pipeline, the joint is located between the pump body and the one-way valve, the other end of the oil return pipeline is connected to the pump body and communicated with the pump cavity, and an oil return valve used for controlling the oil return pipeline to be communicated or closed is arranged on the oil return pipeline. The oil return pipeline is directly connected with the pump body, and backflow oil directly returns to the pump cavity, so that the flowing path and backflow resistance of the backflow oil can be reduced, the pressure in the pump can be balanced more directly and quickly, and the problem that the pump body is difficult to start is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of fuel pumps, in particular to an electric fuel pump. Background Art

[0002] Electric fuel pumps are widely used in various industrial and mechanical equipment for transporting various industrial oils such as lubricating oils and hydraulic oils. Therefore, the fuel pump needs to adapt to oils with different viscosities and various working environments. There are still some problems in the actual use of existing electric fuel pumps: when the viscosity of the oil is too high, the pressure generated by the fuel pump cannot push the oil into the filling system, resulting in the abnormal operation of the fuel pump; when the system back pressure is too high, the fuel pump will have problems such as difficult startup and too slow pumping speed, causing increased energy consumption, motor heating, and reduced working efficiency.

[0003] In view of the above problems, Chinese Patent No. CN206694205U discloses a refrigerant oil electric fuel pump, including a motor, a pump body and a fuel filling device. The fuel filling device includes an inlet pipe, an outlet pipe and a return pipe. The inlet pipe and the outlet pipe are respectively arranged on both sides of the pump body. A check valve is arranged at the top of the outlet pipe. A return valve connected to the return pipe is arranged on the side wall of the check valve, and the other end of the return pipe is connected to the side of the inlet pipe. Chinese Patent No. CN207196050U discloses a fuel pump provided with a return valve, including a pump body, an inlet oil circuit, an outlet oil circuit and a return oil circuit. A check valve is arranged in the outlet oil circuit. One end of the return oil circuit is communicated with the outlet oil circuit, and the connection part is located between the pump body and the check valve. The other end is communicated with the inlet oil circuit, and a return valve is arranged on the return oil circuit.

[0004] The above two solutions can reduce the back pressure during startup and balance the pressure in the pump by setting a return pipe (return oil circuit) and a return valve (return valve), and to a certain extent solve the problem of difficult startup of the pump body caused by too high oil viscosity or too high system back pressure. However, since the return oil needs to pass through the inlet pipe (inlet oil circuit) first and then enter the pump cavity, this increases the flow path of the return oil, prolongs the response time of pressure balance, increases the flow resistance of the return oil, and reduces the return efficiency, which may partially offset the original advantages of the return design, especially more obvious when dealing with high-viscosity oils. Therefore, such a design still results in a relatively slow startup of the fuel pump.

[0005] Therefore, it is urgent to design an electric fuel pump with a more reasonable return oil path to more quickly and effectively solve the problem of difficult startup caused by too high system back pressure. Summary of the Utility Model

[0006] The technical problem to be solved by the utility model is to overcome the above problems and provide an electric fuel pump that can more quickly and effectively balance the pressure in the pump and improve the startup performance of the pump body.

[0007] The technical solution of the present utility model is as follows:

[0008] An electric fuel pump includes a pump body, an oil inlet pipeline, an oil outlet pipeline and a return oil pipeline. The oil inlet pipeline is connected to the oil inlet of the pump body, and the oil outlet pipeline is connected to the oil outlet of the pump body. A check valve for preventing oil from flowing back is arranged in the oil outlet pipeline. It is characterized in that one end of the return oil pipeline is communicated with the oil outlet pipeline, and the connection part is located between the pump body and the check valve. The other end of the return oil pipeline is connected to the pump body and communicated with the pump cavity. The reflux oil is diverted from the oil outlet pipeline and directly flows back to the pump cavity of the pump body after flowing through the return oil pipeline. A return oil valve for controlling the connection or closing of the return oil pipeline is arranged on the return oil pipeline. Directly connecting the return oil pipeline to the pump body so that the reflux oil directly returns to the pump cavity can reduce the flow path and reflux resistance of the reflux oil, thereby more directly and quickly balancing the pressure inside the pump and solving the problem of difficult starting of the pump body.

[0009] Further, in the above-mentioned electric fuel pump, the pump body includes a pump housing and a pump cover. The pump cavity is formed inside the pump housing. The pump cavity includes an oil suction cavity communicated with the oil inlet and a pressure oil cavity communicated with the oil outlet. The return oil pipeline is connected to the pump cover and communicated with the oil suction cavity of the pump cavity. The return oil pipeline is communicated with the oil suction cavity, and the reflux oil flows back to the oil suction cavity from the pump cover, which can more directly and quickly achieve the balance of the pressure inside the pump.

[0010] Further, in the above-mentioned electric fuel pump, an oil return hole is opened on the pump cover. One end of the oil return hole is connected to the return oil pipeline, and the other end is communicated with the oil suction cavity.

[0011] As an optimization, in the above-mentioned electric fuel pump, an enlarged structure is provided at one end of the oil return hole close to the oil suction cavity, and the enlarged structure forms an enlarged groove communicated with the oil return hole. The enlarged groove can effectively prevent the internal structure of the pump from completely blocking and clogging the oil return hole, ensuring that the oil return channel is always unobstructed.

[0012] Further, in the above-mentioned electric fuel pump, the pump body is a gear pump.

[0013] As an optimization, in the above-mentioned electric fuel pump, the return oil pipeline between the pump body and the return oil valve is set as a transparent pipe. The transparent pipe is convenient for directly observing the reflux situation in the return oil pipeline, such as the flow rate and whether there are bubbles.

[0014] Further, in the above-mentioned electric fuel pump, a protective cover is arranged outside the pump body, and a hole for the return oil pipeline to pass through is opened at the corresponding position of the protective cover. The protective cover can protect the pump body from external impact and extend the service life.

[0015] Further, in the above-mentioned electric fuel pump, a dust cap is provided at the end of the oil outlet pipeline. When the fuel pump is not working, the dust cap can effectively prevent dust and foreign objects from entering the pipeline, avoiding affecting the normal use of the pump body due to the pollution or blockage of the oil circuit system.

[0016] Further, the above-mentioned electric fuel pump further includes a pressure gauge for monitoring the oil outlet pressure, and the pressure gauge is arranged on the oil outlet pipeline or on the oil return pipeline between the oil outlet pipeline and the oil return valve. The pressure gauge can monitor the oil outlet pressure in real time, facilitating the operator to adjust the opening degree of the oil return valve according to the oil outlet pressure to achieve the best working efficiency.

[0017] The beneficial effects of the present utility model are as follows:

[0018] 1. By providing an oil return pipeline and an oil return valve, the back pressure can be reduced when the fuel pump starts, solving the problems of difficult pump body startup and too slow pumping speed caused by too high system back pressure or too high oil viscosity, reducing energy loss, and improving working efficiency;

[0019] 2. The oil return pipeline is directly connected to the pump body, and the reflux oil flows out from the oil outlet pipeline, flows through the oil return pipeline and then directly returns to the oil suction cavity of the pump body. This not only simplifies the flow path of the reflux oil, but also reduces the reflux resistance of the reflux oil. High-viscosity oil products are also more likely to flow back through the oil return pipeline under high back pressure, with high reflux efficiency, which helps to balance the pressure in the pump more directly and quickly, enabling the fuel pump to adjust to the appropriate working state faster, thereby improving the startup performance of the pump. Description of the Drawings

[0020] Figure 1 is a three-dimensional structure diagram of the electric fuel pump of the present utility model.

[0021] Figure 2 is a structure diagram of the oil circuit system of this electric fuel pump.

[0022] Figure 3 is Figure 2 the A-A cross-sectional view of

[0023] Figure 4 is Figure 3 the B-B cross-sectional view of

[0024] Figure 5 is a three-dimensional structure diagram of the pump cover in the electric fuel pump of the present utility model.

[0025] In the figure: 10, electric motor; 1, pump body; 11, pump housing; 12, pump cover; 13, oil inlet; 14, oil outlet; 15, pump chamber; 151, suction chamber; 152, pressure chamber; 2, oil inlet pipeline; 3, oil outlet pipeline; 31, check valve; 32, dust cap; 4, oil return pipeline; 41, oil return valve; 42, oil return hole; 43, enlarged groove; 44, transparent pipe; 5, protective cover; 6, gear; 7, pressure gauge. Detailed implementation manner

[0026] The present utility model will be further described below in conjunction with the accompanying drawings and embodiments:

[0027] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model, rather than indicating or implying that the device or component referred to must have a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0028] As Figures 1 - 4 shown, an electric fuel pump provided in this embodiment includes an electric motor 10, a pump body 1, an oil inlet pipeline 2, an oil outlet pipeline 3, and an oil return pipeline 4. The electric motor 10 is connected to the pump body 1 to drive the pump body 1 to operate.

[0029] The pump body 1 is a gear pump. The pump body 1 includes a pump housing 11 and a pump cover 12. An oil inlet 13 and an oil outlet 14 are provided on the pump housing 11. A pump chamber 15 is formed inside the pump housing 11. The pump chamber 15 includes a suction chamber 151 communicating with the oil inlet 13 and a pressure chamber 152 communicating with the oil outlet 14. The oil inlet pipeline 2 is connected to the oil inlet 13 of the pump body 1, and the oil outlet pipeline 3 is connected to the oil outlet 14 of the pump body 1. A check valve 31 for preventing oil from flowing back is provided in the oil outlet pipeline 3, and a dust cap 32 is provided at the end of the oil outlet pipeline 3. A protective cover 5 is also provided outside the pump body 1.

[0030] One end of the oil return pipeline 4 is connected to the oil outlet pipeline 3, and the connection point is located between the pump body 1 and the one-way valve 31. The other end passes through the protective cover 5 and is connected to the pump cover 12 of the pump body 1, communicating with the oil suction chamber 151 of the pump chamber 15. A hole for the oil return pipeline 4 to pass through is provided at the corresponding position of the protective cover 5. A oil return valve 41 for controlling the connection or closure of the oil return pipeline 4 is provided on the oil return pipeline 4. The oil return valve 41 can adjust the flow rate and achieve opening and closing control. Its forms include but are not limited to ball valves, gate valves, butterfly valves, needle valves, diaphragm valves, etc. The oil return valve 41 can be manually, electrically, pneumatically or hydraulically driven. In this embodiment, the oil return valve 41 can adjust the opening degree to control the gradual connection or gradual closure of the oil return pipeline 4. The connection structure between the oil return pipeline 4 and the pump cover 12 is specifically as follows: An oil return hole 42 is provided on the pump cover 12. One end of the oil return hole 42 is connected to the oil return pipeline 4, and the other end communicates with the oil suction chamber 151. An enlarged structure is provided at one end of the oil return hole 42 close to the oil suction chamber 151. This enlarged structure forms an enlarged groove 43 (as Figure 5 shown) that communicates with the oil return hole, to prevent the gear 6 of the gear pump from completely blocking and clogging the oil return hole 42 and ensure that the oil return channel always remains unobstructed.

[0031] To facilitate observing the situation inside the oil return pipeline 4, the oil return pipeline 4 between the pump body 1 and the oil return valve 41 is set as a transparent pipe 44.

[0032] This electric fuel pump further includes a pressure gauge 7 for monitoring the oil outlet pressure. The pressure gauge 7 is provided on the oil outlet pipeline 3 or on the oil return pipeline 4 between the oil outlet pipeline 3 and the oil return valve 41. In this embodiment, the pressure gauge 7 is installed on the oil return pipeline 4 between the oil outlet pipeline 3 and the oil return valve 41.

[0033] The working process of the electric fuel pump of the present utility model is as follows:

[0034] Before the electric fuel pump is started, it should be ensured that the oil return valve 41 is in the open state. After starting, the motor 10 drives the pump body 1 to start running. The oil fluid enters the oil suction chamber 151 from the oil inlet pipeline 2, and then is pressurized in the oil pressure chamber 152 and then enters the oil outlet pipeline 3. Since the oil return pipeline 4 is in a connected state, the oil fluid will be diverted from the oil outlet pipeline 3, flow through the oil return pipeline 4 and directly return to the oil suction chamber 151 (the oil return path is as Figure 1 shown by the arrow). At this time, the system back pressure is small, and the pump body 1 can be started smoothly. And the return of the oil fluid can quickly balance the pressure inside the pump, so that the fuel pump is adjusted to a suitable working state. Observe the state of the oil fluid in the transparent oil return pipeline 4. After there are no bubbles in the oil return pipeline 4, control the opening degree of the oil return valve 41 to gradually close the oil return pipeline 4. As this process progresses, the pressure in the oil outlet pipeline 3 gradually rises to be sufficient to push open the one-way valve 31 in the oil outlet pipeline 3, and the oil fluid begins to be injected into the filling system, and the fuel pump starts to work normally.

[0035] Finally, it is understandable that those of ordinary skill in the art can make various other corresponding changes and deformations according to the technical concept of the present utility model, and all such changes and deformations shall fall within the protection scope of the claims of the present utility model.

Claims

1. An electric refueling pump, comprising a pump body, an oil inlet pipeline, an oil outlet pipeline and an oil return pipeline, wherein the oil inlet pipeline is connected to the oil inlet of the pump body, the oil outlet pipeline is connected to the oil outlet of the pump body, and a one-way valve for preventing oil backflow is arranged in the oil outlet pipeline, characterized in that: One end of the oil return pipeline is connected to the oil outlet pipeline and the connection is located between the pump body and the one-way valve. The other end of the oil return pipeline is connected to the pump body and connected to the pump chamber. The return oil is diverted from the oil outlet pipeline and flows directly back to the pump chamber of the pump body after flowing through the oil return pipeline. The oil return pipeline is provided with an oil return valve for controlling the connection or closing of the oil return pipeline. The pump body comprises a pump housing and a pump cover. The pump housing is provided with a pump chamber, the pump chamber comprises an oil suction chamber connected to an oil inlet and an oil pressure chamber connected to an oil outlet. The oil return pipeline is connected to the pump cover and is connected to the oil suction chamber of the pump chamber. The pump cover is provided with an oil return hole, one end of which is connected to the oil return pipeline, and the other end of which is connected to the oil suction chamber; An enlarged structure is provided at one end of the oil return hole close to the oil suction chamber, and the enlarged structure forms an enlarged groove communicated with the oil return hole.

2. The electric refueling pump according to claim 1, characterized in that: The pump body is a gear pump.

3. The electric refueling pump according to claim 1, characterized in that: The oil return pipeline between the pump body and the oil return valve is arranged as a transparent tube.

4. The electric refueling pump according to claim 1, characterized in that: A protective cover is arranged outside the pump body, and a hole for the oil return pipeline to pass through is opened at a corresponding position of the protective cover.

5. The electric refueling pump according to claim 1, characterized in that: A dust cap is provided at the end of the oil outlet pipeline.

6. The electric refueling pump according to claim 1, characterized in that: It also includes a pressure gauge for monitoring the oil outlet pressure, and the pressure gauge is arranged on the oil outlet pipeline or on the oil return pipeline between the oil outlet pipeline and the oil return valve.

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