An engine oil supply system

Abstract

The utility model relates to the technical field of engine, disclose an engine oil supply system, including oil tank, negative pressure pump and engine, the built-in carburetor and negative pressure unit of engine, negative pressure pump is connected negative pressure unit through pipeline, its characterized in that, the oil tank sets up first oil outlet nozzle and second oil outlet nozzle, first oil outlet nozzle connects second oil outlet nozzle and carburetor through pipeline simultaneously, negative pressure pump is located the connecting pipeline of first oil outlet nozzle with second oil outlet nozzle and forms the passage. Avoid the difficulty of engine starting, reduced the risk of carburetor oil overflow under the condition of larger vibration.

Description

Technical Field

[0001] This utility model relates to the field of engine technology, specifically to an engine fuel supply system. Background Technology

[0002] Current fuel tank supply systems mostly adopt the fuel tank outlet-fuel switch-carburetor scheme. However, under some special operating conditions, such as high load and high temperature conditions, the engine has a greater demand for fuel due to the high load. At high temperatures, gasoline vapor lock is generated in the fuel line, which hinders the flow of gasoline. This can lead to insufficient fuel supply to the engine under these conditions, causing sloshing or even stalling. A negative pressure pump can solve the problem of insufficient fuel supply to a certain extent.

[0003] For example, Chinese patent document CN218953465U discloses a general-purpose engine, including an engine block and a throttle valve body. One end of the engine block is provided with a wind deflector, and it also includes a feed pipe for connecting to a fuel tank. The feed pipe is connected to the throttle valve body through a fuel pump. The fuel pump is connected to the engine block, the feed port of the fuel pump is connected to the feed pipe, the discharge port of the fuel pump is connected to the throttle valve body, and a negative pressure pump is provided on the feed pipe.

[0004] For example, Chinese patent document CN209083450U discloses an engine fuel supply system, including a fuel tank body and a carburetor mounted on the engine. The fuel supply system also includes an auxiliary fuel tank. The fuel tank body is connected to the auxiliary fuel tank via a fuel circuit mechanism, and the auxiliary fuel tank is connected to the carburetor via a pipe. The auxiliary fuel tank is higher than the carburetor. The fuel circuit mechanism includes a fuel pump, which includes an inlet nozzle, an outlet nozzle, and a valve stem. The auxiliary fuel tank is provided with an inlet and an outlet nozzle. The inlet nozzle is connected to the lower end of the fuel tank body via pipe A, the outlet nozzle is connected to the inlet nozzle via pipe B, the valve stem is connected to the crankcase on the engine via pipe C, and the outlet nozzle is connected to the carburetor via pipe D.

[0005] While a negative pressure pump can solve the problem of insufficient fuel supply to some extent, in a single negative pressure pump fuel supply system, when gasoline is first added to the fuel tank or when there is not much fuel left in the tank (when the fuel level is lower than the position of the negative pressure pump), the gasoline in the fuel tank cannot flow into the carburetor due to the drop. If there is no gasoline in the carburetor cup at this time, starting difficulties will occur. Utility Model Content

[0006] To solve the technical problem of difficult engine starting, this utility model provides an engine fuel supply system, including a fuel tank, a negative pressure pump, and an engine. The engine has a built-in carburetor and a negative pressure unit. The negative pressure pump is connected to the negative pressure unit through a pipeline. The fuel tank is provided with a first fuel outlet and a second fuel outlet. The first fuel outlet is connected to both the second fuel outlet and the carburetor through a pipeline. The negative pressure pump is located on the connecting pipeline between the first fuel outlet and the second fuel outlet, forming a passage.

[0007] To balance the pressure and avoid starting difficulties, the first fuel outlet is connected to the second fuel outlet and the carburetor via a branch pipe.

[0008] Furthermore, to reduce the risk of carburetor spillage under conditions of significant vibration, the branched pipeline includes fuel line one, fuel line two, fuel line three, and a tee connector. The first nozzle is connected to the tee connector via fuel line one. The other two ends of the tee connector are connected to fuel line two and fuel line three, respectively. Fuel line two is connected to the outlet of the negative pressure pump, and fuel line three is connected to the carburetor. The nozzle connected to the tee connector plays a role in balancing pressure. When the pressure generated by the negative pressure pump is working is greater than the fuel level pressure inside the fuel tank, the excess fuel will flow back to the fuel tank through the tee, fuel line one, and nozzle one, thus reducing the risk of carburetor spillage under conditions of significant vibration.

[0009] To facilitate oil supply from the second oil outlet, the second oil outlet is connected to the inlet of the negative pressure pump via an oil pipe.

[0010] To facilitate fuel supply control, a fuel switch is installed between the three-way connector and the carburetor.

[0011] Preferably, the negative pressure pump is a pressure oil pump, the pressure tap of the pressure oil pump is connected to the negative pressure pipe, and the negative pressure pipe is connected to the negative pressure unit.

[0012] This utility model has the following beneficial effects: 1. In existing technologies, while negative pressure pumps can solve the problem of insufficient fuel supply to some extent, in the case of a standalone negative pressure pump fuel supply system, the negative pressure nozzle of the negative pressure pump needs to be connected to the engine (block, cylinder head cover, intake manifold). These places often contain engine oil / gasoline and oil vapor, which condense in the negative pressure pipe. Therefore, the negative pressure pump generally needs to be placed above the engine so that the condensed oil can naturally flow back to the engine. The fuel tank is generally located above the engine, and to achieve higher space utilization, there is usually no direct connection between the fuel tank and the engine. There will be too much distance (this distance is generally smaller than the diameter of the negative pressure pump), so the position of the negative pressure pump is generally higher than the bottom of the fuel tank. Because there is a negative pressure pump between the fuel tank and the carburetor, when the engine is not started, fuel can only seep out from the edge of the negative pressure pump diaphragm. Therefore, in a single negative pressure pump fuel supply system, when gasoline is added to the fuel tank for the first time or when there is not much fuel left in the fuel tank (when the fuel level is lower than the position of the negative pressure pump), the gasoline in the fuel tank cannot flow into the carburetor through the drop. If there is no gasoline in the carburetor cup at this time, starting difficulties will occur. This invention employs a dual-outlet nozzle structure, connecting the negative pressure pump outlet to the two nozzles in the fuel tank via a three-way connector. On one hand, in the first scenario described above, gasoline in the fuel tank can directly enter the carburetor through either the first or second outlet nozzle, avoiding starting difficulties. On the other hand, the three-way connector connecting the outlet nozzles also serves to balance pressure. When the pressure generated by the negative pressure pump is greater than the fuel level pressure inside the fuel tank, the excess fuel will flow back to the fuel tank through the three-way connector, fuel line one, and outlet one, reducing the risk of carburetor spillage under conditions of significant vibration. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of an embodiment of the engine fuel supply system of this utility model. Detailed Implementation

[0014] The following detailed description illustrates the specific implementation method: The reference numerals in the accompanying drawings include: fuel tank 1, negative pressure pump 2, outlet 201, inlet 202, pressure tap 203, engine 3, carburetor 4, negative pressure unit 5, first fuel outlet 6, second fuel outlet 7, fuel line 1 8, fuel line 2 9, fuel line 3 10, fuel line 4 11, tee connector 12, fuel switch 13, and negative pressure pipe 14.

[0015] Example 1 like Figure 1As shown, an engine fuel supply system includes a fuel tank 1, a negative pressure pump 2, and an engine 3. The engine 3 has a built-in carburetor 4 and a negative pressure unit 5. The negative pressure pump 2 is connected to the negative pressure unit 5 through a negative pressure pipe 14. The fuel tank 1 is provided with a first fuel outlet 6 and a second fuel outlet 7. The first fuel outlet 6 is connected to both the second fuel outlet 7 and the carburetor 4 through a pipeline. The negative pressure pump 2 is located on the connecting pipeline between the first fuel outlet 6 and the second fuel outlet 7, forming a passage. The outlet 201 of the negative pressure pump 2 is connected to the first fuel outlet 6, and the inlet 202 of the negative pressure pump 2 is connected to the second fuel outlet 7.

[0016] The first fuel nozzle 6 is connected to the second fuel nozzle 7 and the carburetor 4 via a branch pipe.

[0017] The branched pipeline includes oil pipe 8, oil pipe 9, oil pipe 10, and a three-way connector 12. The first fuel outlet 6 is connected to the three-way connector 12 via oil pipe 8. The other two ends of the three-way connector 12 are connected to oil pipe 9 and oil pipe 10, respectively. Oil pipe 9 is connected to the outlet 201 of the negative pressure pump 2, and oil pipe 10 is connected to the carburetor 4. The fuel outlet connected to the three-way connector 12 plays a role in balancing pressure. When the pressure generated by the negative pressure pump 2 is greater than the fuel level pressure inside the fuel tank 1, the excess fuel will flow back to the fuel tank 1 through the three-way connector 12, oil pipe 8, and fuel outlet 1, reducing the risk of fuel spillage from the carburetor 4 under conditions of greater vibration.

[0018] The second oil outlet 7 is connected to the inlet 202 of the negative pressure pump 2 via oil pipe 11.

[0019] A fuel switch 13 is provided on the fuel line 3 10 between the three-way interface 12 and the carburetor 4.

[0020] The negative pressure pump 2 is a pressure oil pump, and the pressure tap 203 of the pressure oil pump is connected to the negative pressure pipe 14, which is connected to the negative pressure unit 5.

[0021] The above descriptions are merely embodiments of this utility model. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are knowledgeable of all existing technologies in that field, and possess the ability to apply conventional experimental methods prior to that date. Therefore, those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in conjunction with their own capabilities. Typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An engine fuel supply system, comprising a fuel tank, a negative pressure pump, and an engine, wherein the engine has a built-in carburetor and a negative pressure unit, and the negative pressure pump is connected to the negative pressure unit via a pipeline, characterized in that, The fuel tank is equipped with a first fuel outlet and a second fuel outlet. The first fuel outlet is connected to both the second fuel outlet and the carburetor via a pipeline. The negative pressure pump is located on the connecting pipeline between the first fuel outlet and the second fuel outlet, forming a passage.

2. The engine fuel supply system according to claim 1, characterized in that: The first fuel outlet is connected to the second fuel outlet and the carburetor via a branch pipe.

3. The engine fuel supply system according to claim 2, characterized in that: The branched pipeline includes oil pipe one, oil pipe two, oil pipe three and a three-way connector. The first oil outlet is connected to the three-way connector via oil pipe one. The other two ends of the three-way connector are respectively connected to oil pipe two and oil pipe three. Oil pipe two is connected to the outlet of the negative pressure pump, and oil pipe three is connected to the carburetor.

4. The engine fuel supply system according to claim 3, characterized in that: The second oil outlet is connected to the inlet of the negative pressure pump via an oil pipe.

5. The engine fuel supply system according to claim 4, characterized in that: A fuel switch is installed between the three-way connector and the carburetor.

6. The engine fuel supply system according to claim 5, characterized in that: The negative pressure pump is a pressure-type oil pump, and the pressure tap of the pressure-type oil pump is connected to the negative pressure pipe, which is connected to the negative pressure unit.

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