Pressure stabilizing structure of monoblock pump low-pressure fuel system of full-methanol compression ignition loader

Abstract

The utility model discloses a pressure stabilizing structure of a monoblock pump low-pressure fuel system of a full-methanol compression ignition loader. The pressure stabilizing structure comprises a monoblock pump, a fuel tank, a pressure stabilizing valve and a low-pressure fuel channel, the low-pressure fuel channel comprises a filter, a low-pressure fuel pump and a pressure regulating valve, an inlet of the filter is connected with the fuel tank, an outlet of the filter is connected with an inlet of the pressure regulating valve through the low-pressure fuel pump, a pressure relief opening of the pressure regulating valve is connected with a backflow opening of the filter, and an outlet of the pressure regulating valve is connected with a low-pressure fuel inlet of a low-pressure fuel cavity of the unit pump. An inlet of the pressure maintaining valve communicates with a low-pressure fuel outlet of the low-pressure fuel cavity of the unit pump, and an outlet of the pressure maintaining valve is connected with the fuel tank. The pressure regulating valve and the pressure stabilizing valve are used for regulating and stabilizing pressure, the pressure of methanol fuel can be regulated and stabilized, and then the pressure stability of fuel supply of the monoblock pump low-pressure fuel system can be effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of loaders, and in particular to a pressure stabilizing structure for a unit pump low-pressure fuel system of a full methanol compression ignition loader. Background Technology

[0002] Traditional loaders primarily use internal combustion engines as their power source, resulting in significant fuel consumption and environmental pollution. To address this, some researchers have developed methanol compression-ignition loaders using methanol engines. These loaders utilize methanol as fuel and offer advantages such as safety, environmental friendliness, high efficiency, energy saving, comfort, and maneuverability.

[0003] Many existing methanol compression ignition loaders use electronically controlled unit pump fuel systems to supply methanol fuel to their engines. This system is a time-controlled pulse-type high-pressure fuel injection system. The ECU controls the opening and closing of solenoid valves to manage the high and low pressure fuel channels. When the pressure in the unit pump's plunger chamber is lower than the pressure in the low-pressure fuel channel, the low-pressure methanol fuel enters the plunger chamber first. Then, the plunger moves upward, compressing and pressurizing the methanol fuel to produce high-pressure methanol fuel. This high-pressure methanol fuel is then controlled by the ECU to enter the high-pressure fuel channel before being injected into the fuel injector. Fluctuations in the pressure build-up process of the high-pressure methanol fuel in the unit pump (i.e., during the compression and pressurization process) directly affect the unit pump, leading to unstable engine output power. One of the reasons for the fluctuations in the pressure build-up of high-pressure methanol fuel is the poor pressure stability of the fuel pressure in the low-pressure fuel passage. If the fuel pressure in the low-pressure fuel passage is too low, there will be insufficient methanol fuel in the plunger chamber and bubbles will form. As the plunger rises, the bubbles will be compressed and burst, resulting in cavitation. Cavitation will cause fluctuations in the pressure build-up, thus affecting the output of engine power. If the fuel pressure in the low-pressure fuel passage is too high, methanol fuel will leak into the lubricating oil passage, contaminating the lubricating oil and causing damage to related components.

[0004] In view of the above problems, it is necessary to study a pressure stabilization structure for the unit pump low-pressure fuel system of a full methanol compression ignition loader, which can improve the pressure stability of the fuel supplied by the unit pump low-pressure fuel system. Utility Model Content

[0005] The purpose of this invention is to provide a pressure stabilizing structure for the low-pressure fuel system of a unit pump in a methanol compression ignition loader, which can improve the pressure stability of the fuel supplied by the unit pump low-pressure fuel system.

[0006] To achieve the above objectives, the solution of this utility model is:

[0007] A pressure-stabilizing structure for a unit pump low-pressure fuel system of a methanol compression ignition loader includes a unit pump, a fuel tank, a pressure-stabilizing valve, and a low-pressure fuel passage. The low-pressure fuel passage includes a filter, a low-pressure fuel pump, and a pressure regulating valve. The inlet of the filter is connected to the fuel tank, and the outlet of the filter is connected to the inlet of the pressure regulating valve through the low-pressure fuel pump. The pressure relief port of the pressure regulating valve is connected to the return port of the filter, and the outlet of the pressure regulating valve is connected to the low-pressure fuel inlet of the low-pressure fuel chamber of the unit pump. The inlet of the pressure-stabilizing valve is connected to the low-pressure fuel outlet of the low-pressure fuel chamber of the unit pump, and the outlet of the pressure-stabilizing valve is connected to the fuel tank.

[0008] The low-pressure fuel chamber of the unit pump has two low-pressure fuel inlets; the low-pressure fuel passage also includes a tee, the outlet of the pressure regulating valve is connected to the two low-pressure fuel inlets of the unit pump through the tee, the inlet of the tee is connected to the outlet of the pressure regulating valve, and the two outlets of the tee are respectively connected to the two low-pressure fuel inlets of the unit pump.

[0009] The two low-pressure fuel inlets of the low-pressure fuel chamber of the unit pump are located on opposite sides of the unit pump, and the low-pressure fuel chamber is connected to the plunger chamber of the unit pump.

[0010] The pressure regulating valve is equipped with a pressure sensor for monitoring the methanol fuel pressure in the low-pressure fuel chamber of the unit pump.

[0011] The pressure sensor is electrically connected to the vehicle controller.

[0012] The vehicle controller is electrically connected to the instrument.

[0013] The vehicle controller is electrically connected to the engine electronic control unit.

[0014] With the above-described solution, the working principle of this invention is as follows: Methanol fuel in the fuel tank is first filtered through a filter before being delivered to the low-pressure fuel pump. The low-pressure fuel pump then delivers the methanol fuel to a pressure regulating valve, which adjusts the pressure of the methanol fuel to the required range before delivering it to the unit pump. If the pressure of the methanol fuel exceeds the requirement, the pressure regulating valve returns the excess methanol fuel to the filter. Furthermore, the low-pressure fuel chamber of the unit pump is connected to the fuel tank via a pressure stabilizing valve. If the pressure of the methanol fuel in the low-pressure fuel chamber of the unit pump exceeds the requirement, the pressure stabilizing valve controls the excess methanol fuel to flow back to the fuel tank, preventing excessive pressure in the low-pressure fuel chamber of the unit pump. As described above, this invention, through pressure regulating and stabilizing valves, can regulate and stabilize the pressure of methanol fuel, thereby effectively improving the pressure stability of the fuel supplied by the unit pump's low-pressure fuel system.

[0015] In addition, this utility model is also equipped with a pressure sensor to monitor the methanol fuel pressure in the low-pressure fuel chamber of the unit pump in real time. When the pressure sensor detects an abnormality, the vehicle controller can take countermeasures to protect the methanol engine. At the same time, the vehicle controller will also feed back the abnormality to the instrument panel to remind the user of the abnormal fault and facilitate maintenance personnel to carry out maintenance. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the present invention.

[0017] Description of labels:

[0018] Unit pump 1,

[0019] Fuel tank 2,

[0020] Low-pressure fuel passage 3,

[0021] Filter 31, low-pressure fuel pump 32, pressure regulating valve 33, tee 34

[0022] Pressure regulator 4,

[0023] Pressure sensor 5,

[0024] Vehicle controller 6, instrument panel 7,

[0025] Engine electronic control unit 8. Detailed Implementation

[0026] To further explain the technical solution of this utility model, the following detailed description is provided through specific embodiments.

[0027] like Figure 1 As shown, this utility model discloses a pressure stabilizing structure for a unit pump low-pressure fuel system of a methanol compression ignition loader, which includes a unit pump 1, a fuel tank 2, a pressure stabilizing valve 4, and a low-pressure fuel passage 3. The low-pressure fuel passage 3 includes a filter 31, a low-pressure fuel pump 32, and a pressure regulating valve 33. The inlet of the filter 31 is connected to the fuel tank 2, and the outlet of the filter 31 is connected to the inlet of the pressure regulating valve 33 via the low-pressure fuel pump 32. The pressure relief port of the pressure regulating valve 33 is connected to the return port of the filter 31, and the outlet of the pressure regulating valve 33 is connected to the low-pressure fuel inlet of the low-pressure fuel chamber of the unit pump 1. The inlet of the pressure stabilizing valve 4 is connected to the low-pressure fuel outlet of the low-pressure fuel chamber of the unit pump 1, and the outlet of the pressure stabilizing valve 4 is connected to the fuel tank 2. The low-pressure fuel chamber of the unit pump 1 is connected to the plunger chamber of the unit pump 1.

[0028] The working principle of this invention is as follows: Methanol fuel in fuel tank 2 is first filtered through filter 31 and then delivered to low-pressure fuel pump 32. Low-pressure fuel pump 32 delivers the methanol fuel to pressure regulating valve 33, which adjusts the pressure of the methanol fuel to the required range before delivering it to unit pump 1. If the pressure of the methanol fuel exceeds the requirement, pressure regulating valve 33 returns the excess methanol fuel to filter 31. Furthermore, the low-pressure fuel chamber of unit pump 1 is also connected to fuel tank 2 via pressure stabilizing valve 4. If the pressure of the methanol fuel in the low-pressure fuel chamber of unit pump 1 exceeds the requirement, pressure stabilizing valve 4 controls the excess methanol fuel to flow back to fuel tank 2, preventing excessive pressure in the low-pressure fuel chamber of unit pump 1. As described above, this invention, through pressure regulating valve 33 and pressure stabilizing valve 4, can regulate and stabilize the pressure of methanol fuel, thereby effectively improving the pressure stability of the fuel supplied by the unit pump low-pressure fuel system.

[0029] In an embodiment of this invention, the unit pump 1 may have two low-pressure fuel inlets; and the low-pressure fuel channel 3 further includes a three-way valve 34, through which the outlet of the pressure regulating valve 33 is connected to the two low-pressure fuel inlets of the unit pump 1, the inlet of the three-way valve 34 is connected to the outlet of the pressure regulating valve 33, and the two outlets of the three-way valve 34 are respectively connected to the two low-pressure fuel inlets of the unit pump 1; thus, methanol fuel can be input into the unit pump 1 from the two low-pressure fuel inlets, improving the pressure stability of methanol fuel entering the unit pump 1. The two low-pressure fuel inlets of the unit pump 1 are located on opposite sides of the unit pump 1, so that when methanol fuel is input into the unit pump 1 from the two low-pressure fuel inlets, the methanol fuel can be balanced, further improving the pressure stability of methanol fuel entering the unit pump 1.

[0030] In this embodiment of the invention, the pressure regulating valve 4 is equipped with a pressure sensor 5 for monitoring the methanol fuel pressure in the low-pressure fuel chamber of the unit pump 1, thereby enabling monitoring of the methanol fuel pressure. The pressure sensor 5 is electrically connected to the vehicle controller 6, allowing the vehicle controller 6 to acquire methanol fuel pressure information in the low-pressure fuel chamber of the unit pump 1. The vehicle controller 6 is electrically connected to the instrument cluster 7 and the engine electronic control unit 8. When the vehicle controller 6 detects that the methanol fuel pressure in the low-pressure fuel chamber of the unit pump 1 is too low via the pressure sensor 5, the vehicle controller 6 sends a message to the instrument cluster 7 to remind the driver that the methanol fuel pressure is too low, allowing the driver to take appropriate measures in a timely manner. When the vehicle controller 6 detects that the methanol fuel pressure in the low-pressure fuel chamber of the unit pump 1 is too high via the pressure sensor 5, the vehicle controller 6 sends a speed-limiting message to the engine electronic control unit 8, causing the engine electronic control unit 8 to limit the speed of the methanol engine, restricting the methanol engine speed to 50% of its rated speed. Simultaneously, the vehicle controller 6 sends a message to the instrument cluster 7 to remind the driver that the methanol fuel pressure is too high, allowing the driver to take appropriate measures in a timely manner. The reasons for the excessively low methanol fuel pressure in the low-pressure fuel chamber of unit pump 1 are: insufficient methanol fuel or damage to the low-pressure fuel pump 32; the reasons for the excessively high methanol fuel pressure in the low-pressure fuel chamber of unit pump 1 are: damage to the pressure regulating valve 33 and / or the pressure stabilizing valve 4.

[0031] The above embodiments and figures are not intended to limit the product form and style of this utility model. Any appropriate changes or modifications made by those skilled in the art should be considered as not departing from the patent scope of this utility model.

Claims

1. A pressure stabilizing structure for a unit pump low-pressure fuel system of a methanol compression ignition loader, characterized in that: This includes the unit pump, fuel tank, pressure regulator, and low-pressure fuel passage; The low-pressure fuel passage includes a filter, a low-pressure fuel pump, and a pressure regulating valve. The filter inlet is connected to the fuel tank, and the filter outlet is connected to the pressure regulating valve inlet via the low-pressure fuel pump. The pressure relief port of the pressure regulating valve is connected to the filter return port, and the pressure regulating valve outlet is connected to the low-pressure fuel inlet of the low-pressure fuel chamber of the unit pump. The pressure regulating valve inlet is connected to the low-pressure fuel outlet of the low-pressure fuel chamber of the unit pump, and the pressure regulating valve outlet is connected to the fuel tank.

2. The pressure stabilizing structure of the unit pump low-pressure fuel system of a full methanol compression ignition loader as described in claim 1, characterized in that: The low-pressure fuel chamber of the unit pump has two low-pressure fuel inlets; the low-pressure fuel passage also includes a tee, the outlet of the pressure regulating valve is connected to the two low-pressure fuel inlets of the unit pump through the tee, the inlet of the tee is connected to the outlet of the pressure regulating valve, and the two outlets of the tee are respectively connected to the two low-pressure fuel inlets of the unit pump.

3. The pressure stabilizing structure of the unit pump low-pressure fuel system of a methanol compression ignition loader as described in claim 2, characterized in that: The two low-pressure fuel inlets of the low-pressure fuel chamber of the unit pump are located on opposite sides of the unit pump, and the low-pressure fuel chamber is connected to the plunger chamber of the unit pump.

4. The pressure stabilizing structure of the unit pump low-pressure fuel system of a full methanol compression ignition loader as described in claim 1, characterized in that: The pressure regulating valve is equipped with a pressure sensor for monitoring the methanol fuel pressure in the low-pressure fuel chamber of the unit pump.

5. The pressure stabilizing structure of the unit pump low-pressure fuel system of a methanol compression ignition loader as described in claim 4, characterized in that: The pressure sensor is electrically connected to the vehicle controller.

6. The pressure stabilizing structure of the unit pump low-pressure fuel system of a full methanol compression ignition loader as described in claim 5, characterized in that: The vehicle controller is electrically connected to the instrument.

7. The pressure stabilizing structure of the unit pump low-pressure fuel system of a methanol compression ignition loader as described in claim 5, characterized in that: The vehicle controller is electrically connected to the engine electronic control unit.

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