Large-flow dual-fuel injection system cooperatively controlled by multiple electromagnetic valves

Abstract

The invention aims to provide a high-flow dual-fuel injection system cooperatively controlled by multiple electromagnetic valves, and belongs to the field of injection systems. Comprising a diesel oil supply module which comprises a fuel filter, an electronic unit pump and a pressure stabilizing assembly; the methanol fuel supply module comprises a conveying pump set and a common rail pipe; a diesel oil and methanol integrated injector structurally comprises a diesel oil injection unit and a methanol injection unit with different control strategies. The diesel oil conveying system and the methanol supply system which are independent of each other are adopted, the dual-fuel mixed injection function is achieved, meanwhile, diesel oil is used as a control medium for methanol injection, and the corrosion risk of methanol to an injector material is reduced. According to the invention, oil supply of the electronic control unit pump is matched with the electronic control injector, and large-flow injection of two fuels of diesel oil and methanol is realized through cooperative control of multiple electromagnetic valves. Through the design of the diaphragm type voltage stabilizer, the influence of oil supply pressure fluctuation of the electronic unit pump on the working performance of the ejector is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of injection systems, specifically dual-fuel injection system. BACKGROUND

[0002] With the transformation of global energy structure and the increasingly stringent environmental regulations, traditional diesel engines face the challenges of reducing emissions, improving fuel economy and adapting to diversified fuels. Methanol, as a clean and renewable alternative fuel, has the advantages of wide sources, clean combustion and low cost, and its application in diesel engines has gradually attracted attention. However, the physical and chemical properties of diesel and methanol differ greatly, and the traditional single-fuel injection system cannot achieve efficient mixing and combustion of the two fuels.

[0003] Traditional diesel-methanol dual-fuel injection systems mostly use mechanical or single solenoid valve control schemes. Although this scheme can achieve dual-fuel supply, it faces some problems in actual application, such as insufficient control accuracy, limited response speed of single solenoid valve under high-flow conditions, difficulty in achieving dynamic precise adjustment of dual-fuel ratio, leading to unstable combustion or deteriorated emissions, etc. In addition, the corrosiveness and low lubricity of methanol pose higher requirements on the materials and control strategies of the injection system. SUMMARY

[0004] The purpose of the present application is to provide a multi-solenoid valve coordinated control large-flow dual-fuel injection system that not only improves the flexibility and response speed of the injection system, but also reduces system complexity and cost.

[0005] The purpose of the present application is achieved as follows:

[0006] The multi-solenoid valve coordinated control large-flow dual-fuel injection system of the present application is characterized by comprising an electronic control unit, a common rail pipe, a diaphragm type pressure stabilizer, a diesel tank, a methanol storage tank, a diesel-methanol integrated injector, and an electronic control unit. The diesel tank is connected to the oil inlet of the electronic control unit through a fuel filter, the oil outlet of the electronic control unit is connected to the diaphragm type pressure stabilizer, the return oil port of the electronic control unit, the diesel tank and the diaphragm type pressure stabilizer are connected through a first three-way valve, the methanol storage tank is connected to the common rail pipe through a delivery pump, the diesel-methanol integrated injector is connected to the diaphragm type pressure stabilizer, the common rail pipe, the diesel tank and the methanol storage tank, respectively, and the electronic control unit is connected to the electronic control unit, the common rail pipe, the delivery pump, the diesel-methanol integrated injector and the diaphragm type pressure stabilizer through a signal pipe.

[0007] The present application can also include:

[0008] 1. The diesel-methanol integrated injector includes a connected methanol injection unit and a diesel injection unit. A No. 1 diesel oil return port is provided on the top of the methanol injection unit, and a methanol solenoid valve assembly is provided below the No. 1 diesel oil return port. The methanol solenoid valve assembly includes a first compression return spring and a first control armature below it. A first solenoid valve control electromagnet and a first solenoid valve control coil are provided outside the first compression return spring. A first needle valve control chamber is provided below the first control armature. A first return oil throttle hole is provided on the upper part of the first needle valve control chamber. The first return oil throttle hole is sealed by a first ball valve installed at the bottom of the first control armature. A first diesel oil inlet is provided on the side of the methanol injection unit. The first diesel oil inlet is connected to the first needle valve control chamber through the first oil inlet throttle hole. A first needle valve is provided below the first needle valve control chamber. A methanol spray hole is provided below the first needle valve. A first needle valve return spring is provided outside the first needle valve. A methanol storage chamber and a methanol upper chamber are provided at the lower part of the methanol injection unit. The methanol storage chamber is connected to the common rail pipe and the methanol spray hole respectively.

[0009] 2. A No. 2 diesel oil return port is provided on the top of the diesel injection unit, and a diesel solenoid valve assembly is provided below the No. 2 diesel oil return port. The diesel solenoid valve assembly includes a second compression type return spring and a second control armature below it. A second solenoid valve control electromagnet and a second solenoid valve control coil are provided outside the second compression return spring. A second needle valve control chamber is provided below the second control armature. A second return oil throttling hole is provided on the upper part of the second needle valve control chamber. The second return oil throttling hole is sealed by a second ball valve installed at the bottom of the second control armature. A second diesel oil inlet is provided on the side of the diesel injection unit. The second diesel oil inlet is connected to the second needle valve control chamber through the second oil inlet throttling hole. A second needle valve is provided below the second needle valve control chamber. A diesel spray hole is provided below the second needle valve. A second needle valve return spring is provided outside the second needle valve. An oil storage tank is provided outside the second needle valve, and the oil storage tank is connected to the second diesel oil inlet through a diesel inlet pipeline.

[0010] 3. The No. 1 diesel return port, the No. 2 diesel return port and the diesel tank are connected through the second three-way valve; the first diesel inlet, the second diesel inlet and the diaphragm type pressure stabilizer are connected through the third three-way valve; the methanol upper chamber, the common rail pipe and the methanol storage chamber are connected through the fourth three-way valve.

[0011] 4. The diaphragm-type pressure stabilizer includes a shell, with a fuel inlet and an oil return valve arranged on both sides of the shell. An elastic diaphragm is installed inside the shell, one side of the elastic diaphragm is a pressure-stabilizing chamber, which is connected to the fuel inlet and the oil return port respectively. A valve is arranged on the other side of the elastic diaphragm, and a compression spring is installed between the elastic diaphragm and the valve.

[0012] 5. The methanol in the methanol storage tank flows into the common rail pipe through the delivery pump and then into the methanol storage chamber through the delivery pipeline. The low-pressure diesel fuel in the diesel tank first passes through the fuel filter and enters the unit pump through the oil inlet of the electronically controlled unit pump. After the electronically controlled unit pump receives the signal from the electronic control unit, the high-pressure diesel fuel from the electronically controlled unit pump enters the diaphragm-type pressure regulator. The high-pressure diesel fuel enters the pressure regulating chamber from the pressure regulator inlet. When the high-pressure diesel fuel flows through the elastic diaphragm, the diaphragm senses the pressure change. When the pressure exceeds the set value, the elastic diaphragm deforms and pushes the compression spring. The valve adjusts its opening according to the movement of the elastic diaphragm to control the fuel flow. When the pressure is too high, the return valve automatically opens to release the excess pressure.

[0013] After the pressure is stabilized by the pressure stabilizer, the high-pressure diesel is diverted through the three-way valve. Part of it flows to the methanol injection unit, enters from the first diesel inlet, enters the first needle valve control chamber through the first oil inlet throttle hole, and acts on the first needle valve through the first needle valve return spring, so that the first needle valve remains stationary; the other part flows to the diesel injection unit, and flows into the second needle valve control chamber and the oil tank respectively through the second diesel inlet pipeline. Under the combined action of the pressure in the second needle valve control chamber and the preload force of the needle valve spring, the second needle valve remains stationary.

[0014] 6. During a fuel supply period of the electronically controlled unit pump, when the diesel solenoid valve assembly of the diesel injection unit is in an inoperative state and the first solenoid valve control coil in the methanol injection unit begins to be energized, current flowing through the first solenoid valve control coil generates an electromagnetic force, which attracts the first control armature to move upward. The movement of the first control armature drives the first ball valve to open the first oil return throttle orifice. As the first oil return throttle orifice opens, the pressure in the first needle valve control chamber drops, causing the first needle valve to move upward, overcoming the force of the first needle valve return spring, opening the passage between the methanol storage chamber and the spray hole chamber, and ultimately spraying the methanol through the spray hole. Since the diesel solenoid valve assembly is inoperative, the diesel injection unit remains closed and no diesel injection is performed. When the diesel solenoid valve assembly of the diesel injection unit is energized and the first solenoid valve control coil in the methanol injection unit is deenergized, the first needle valve on the methanol injection side continues to maintain its initial static state, and no methanol injection is performed. The diesel solenoid valve assembly is energized, opening the oil return passage in the second needle valve control chamber. The pressure drop in the second needle valve control chamber causes the needle valve to open, and high-pressure diesel is sprayed from the diesel spray hole, achieving a separate supply of high-pressure diesel.

[0015] 7、In the electric control unit pump one oil supply duration, diesel fuel injection unit in the diesel fuel solenoid valve assembly first energized work, the first solenoid control coil at this time is in the non energized state, the second needle valve control chamber back to the oil channel opens, so that the second needle valve opens, high pressure diesel fuel through the diesel fuel injection hole is sprayed out; After the diesel fuel solenoid valve assembly is powered off, high pressure diesel fuel stops injection, the first solenoid control coil starts to energize, the current flows through the coil to produce electromagnetic force, attract the first control armature to move up, the first ball valve opens the first back to the oil throttle hole, the pressure in the first needle valve control chamber drops, causing the first needle valve to overcome the force of the first needle valve return spring and move up, opening the channel between the methanol storage chamber and the injection hole chamber, and realizing the large flow injection of methanol through the methanol injection hole (5-13).

[0016] 8、At the end of the oil supply stage, the first solenoid control coil is deenergized, the first control armature returns to the initial position under the action of the first compression return spring, the first ball valve reseals the first back to the oil throttle hole, and the oil pressure in the first needle valve control chamber rises, cooperating with the first needle valve return spring, the first needle valve drops, closing the methanol injection hole and stopping the injection of methanol.

[0017] The advantages of the present application are:

[0018] 1、The present application adopts separate diesel fuel delivery system and methanol supply system, which realizes dual fuel mixed injection while using diesel fuel as the control medium for methanol injection, thereby reducing the corrosion risk of methanol to the injector material.

[0019] 2、The present application effectively improves the influence of the pressure fluctuation of the electric control unit pump on the working performance of the injector through the structural design of the diaphragm type pressure stabilizer.

[0020] 3、The present application realizes large flow injection of diesel fuel and methanol through the cooperation of the electric control unit pump and the electric control injector, and adopts multi solenoid valve cooperative control technology. BRIEF DESCRIPTION OF DRAWINGS

[0021] Fig. 1 The structural schematic diagram of the present application is shown in the figure;

[0022] Fig. 2 The structural schematic diagram of the diesel-methanol integrated injector is shown in the figure;

[0023] Fig. 3 The structural schematic diagram of the diaphragm type pressure stabilizer is shown in the figure.

[0024] Reference numerals: electronically controlled unit pump 1; common rail pipe 2; delivery pump 3; methanol storage tank 4; methanol injection unit 5; diesel injection unit 6; electronic control unit 7; diaphragm type pressure regulator 8; diesel tank 9; three-way valve 10; fuel filter 11; electronically controlled unit pump oil return port 12; electronically controlled unit pump oil inlet 13; No. 1 diesel oil return port 5-1; solenoid valve control coil 5-2; oil inlet throttle hole 5-3; diesel oil inlet 5-4; compression type return spring 5-5; solenoid valve control electromagnet 5-6; control armature 5-7 ; Return oil throttle hole 5-8; Control chamber 5-9; Needle valve No. 1 5-10; Needle valve return spring 5-11; Storage chamber 5-12; Methanol spray hole 5-13; Diesel oil return port No. 2 6-1; Solenoid valve assembly 6-2; Control chamber assembly 6-3; Diesel oil inlet pipe 6-4; Needle valve No. 2 6-5; Oil tank 6-6; Diesel spray hole 6-7; Housing 8-1; Valve 8-2; Compression spring 8-3; Elastic diaphragm 8-4; Bolt 8-5; Return oil valve 8-6; Pressure stabilizing chamber 8-7; Fuel inlet 8-8. DETAILED DESCRIPTION

[0025] The present invention will be described in more detail below with reference to the accompanying drawings:

[0026] Combine Figs. 1-3 The present invention provides a large-flow dual-fuel injection system with coordinated control of multiple solenoid valves, including an electronically controlled unit pump 1, a diaphragm pressure regulator 8, and a fuel filter 11. The fuel in the diesel tank 9 passes through the fuel filter 11 and enters the electronically controlled unit pump 1 via the oil pipeline. The electronically controlled unit pump 1 is then connected to the diaphragm pressure regulator 8 via a pipeline. At the same time, the methanol in the storage tank 4 flows into the common rail pipe 2 through the delivery pump 3; the diesel-methanol integrated injector consists of a diesel injection unit 6 and a methanol injection unit 5, and these two units are respectively connected to the diaphragm pressure regulator 8, the common rail pipe 2, the diesel tank 9, and the methanol storage tank 4 through delivery pipelines; the electronic control unit 7 is connected to the electronically controlled unit pump 1, the methanol injection unit 5, the diesel injection unit 6, and other components through signal pipelines to achieve coordinated work between the various components.

[0027] Fig. 2The structure diagram of diesel-methanol integrated injector, the structure of methanol injection unit 5 includes No. 1 diesel return port 5-1, electromagnetic valve assembly from top to bottom in turn is compression reset spring 5-5, electromagnetic valve control coil 5-2, electromagnetic valve control electromagnet 5-6 and control armature 5-7;The upper part of control cavity 5-9 is provided with return throttle hole 5-8, the ball valve is driven by control armature 5-7 to realize sealing;Diesel oil inlet 5-4 is connected with needle valve control cavity 5-9 through oil inlet throttle hole 5-3;No. 1 needle valve 5-10 is provided with needle valve reset spring 5-11, methanol flow module is provided with storage cavity 5-12, which is connected with the outlet of common rail pipe 2 and methanol injection hole 5-13 respectively;The structure of diesel injection unit 6 from top to bottom includes No. 2 diesel return port 6-1, electromagnetic valve assembly 6-2, control cavity assembly 6-3, diesel oil inlet pipeline 6-4 and No. 2 needle valve 6-5, the upper part of diesel oil inlet pipeline 6-4 is connected with control cavity through oil inlet and throttle hole, and the lower part is connected with oil tank 6-6.

[0028] Fig. 3 The structure diagram of diaphragm type pressure stabilizer, including shell 8-1, valve 8-2, compression spring 8-3, elastic diaphragm 8-4, bolt 8-5, return valve 8-6, pressure stabilizing cavity 8-7, fuel inlet 8-8. Shell 8-1 is provided with fuel inlet 8-8 and return valve 8-6 on both sides, pressure stabilizing cavity 8-7 is communicated with fuel inlet 8-8 and return port respectively, elastic diaphragm 8-4 is installed inside, both sides are fixed by bolt 8-5, compression spring 8-3 is arranged behind elastic diaphragm 8-4, valve 8-2 is arranged at the outlet of pressure stabilizer.

[0029] The methanol in the methanol storage tank 4 flows into the common rail 2 through the delivery pump 3, and then enters the storage cavities 5-12 through the delivery pipeline. The low-pressure diesel fuel in the fuel tank 9 first enters the plunger sleeve of the unit pump through the fuel filter 11 and the fuel supply pipeline from the unit pump inlet 13. The plunger in the unit pump moves upward under the drive of the cam, and the diesel fuel in the plunger sleeve is compressed, and the pressure continuously rises. When the electronic control unit 7 sends a signal to the electronic control unit 7, the electromagnetic valve in the unit pump 1 starts to work, and the high-pressure diesel fuel enters the diaphragm type pressure stabilizer 8 through the high-pressure oil pipeline. The high-pressure diesel fuel enters the pressure stabilizing cavity 8-7 from the stabilizer inlet 8-8. When the high-pressure diesel fuel flows through the elastic diaphragm 8-4, the diaphragm senses the pressure change. When the pressure exceeds the set value, the elastic diaphragm 8-4 deforms and pushes the compression spring 8-3. The compression spring 8-3 provides a pre-tightening force for adjusting the output pressure. By adjusting the pre-tightening force of the spring, the target pressure of the pressure stabilizer 8 can be set. The valve 8-2 adjusts the opening according to the action of the elastic diaphragm 8-4, controls the fuel flow, and thus outputs a stable pressure. When the system pressure is too high, the return valve 8-6 automatically opens to release the excess pressure. After the high-pressure diesel fuel is stabilized in the pressure stabilizer 8, it is divided by the three-way valve in the high-pressure pipeline. Part of it flows to the methanol injection unit 5, enters from the diesel fuel inlet 5-4, passes through the oil inlet throttle hole 5-3 into the needle valve control cavity 5-9. At this time, the oil pressure in the control cavity 5-9 rises, and the No. 1 needle valve 5-10 is kept stationary through the joint action of the needle valve return spring 5-11. The other part flows to the diesel fuel injection unit 6, and flows into the control cavity 6-3 and the lower oil tank 6-6 through the diesel fuel inlet pipeline 6-4, respectively. Under the combined action of the pressure in the control cavity and the pre-tightening force of the needle valve spring, the No. 2 needle valve 6-5 also remains stationary.

[0030] During a fuel supply period of the electronically controlled single pump 1, when the solenoid valve assembly 6-2 of the diesel injection unit 6 is in a non-working state and the solenoid valve control coil 5-2 in the methanol injection unit 5 starts to be energized, the current passes through the solenoid valve control coil 5-2 to generate electromagnetic force, attracting the control armature 5-7 to move upward, and the movement of the control armature 5-7 drives the ball valve to open the return oil throttle hole 5-8. As the return oil throttle hole 5-8 opens, the pressure in the needle valve control chamber 5-9 drops, causing the needle valve 5-10 to overcome the force of the return spring 5-11 and move upward, opening the passage between the storage chamber 5-12 and the spray hole chamber of the methanol inlet module, and finally spraying it out through the spray hole 5-13, realizing A large flow of methanol is injected, while the diesel injection unit 6 remains closed due to the non-operating solenoid valve assembly 6-2, and no diesel injection is performed; when the solenoid valve assembly 6-2 of the diesel injection unit 6 is energized and the solenoid valve control coil 5-2 in the methanol injection unit 5 is not energized, the needle valve No. 1 5-10 on the methanol injection side continues to maintain its initial static state, and methanol is not injected. For the diesel injection unit 6, the solenoid valve assembly 6-2 is energized, and the control armature inside it is attracted by the electromagnetic force, opening the oil return channel of the needle valve control chamber, and the pressure drop in the needle valve control chamber causes the needle valve to open, and high-pressure diesel is ejected from the spray hole 6-7, realizing the separate supply of high-pressure diesel.

[0031] During a fuel supply period of the electronically controlled single pump 1, the solenoid valve assembly 6-2 in the diesel injection unit 6 is first energized, while the solenoid valve control coil 5-2 is in an unpowered state. Due to the action of electromagnetic force, the control armature inside the solenoid valve assembly is attracted, opening the return oil channel of the needle valve control chamber, causing the pressure in the needle valve control chamber to drop, thereby opening the needle valve, and high-pressure diesel is ejected through the spray hole 6-7; after the solenoid valve assembly 6-2 is energized for a period of time, the power is cut off, and the high-pressure diesel stops being sprayed, while the solenoid valve control coil 5-2 starts to be energized, and the current flows through the coil to generate electromagnetic force, which attracts the control armature 5-7 to move upward, and the movement of the armature causes the ball valve to open the return oil throttle hole 5-8. As the throttle hole opens, the needle valve control chamber The pressure in 5-9 continues to drop, causing the needle valve 5-10 to overcome the force of the return spring 5-11 and move upward, opening the channel between the storage chamber 5-12 and the spray hole chamber of the methanol inlet module, and finally realizing a large flow injection of methanol through the spray hole 5-13; at the end of the oil supply, the solenoid valve control coil 5-2 is de-energized, and the control armature 5-7 returns to its initial position under the action of the compression return spring 5-5, and the ball valve reseals the return oil throttle hole 5-8. The oil pressure in the needle valve control chamber 5-9 continues to increase, and with the help of the needle valve return spring 5-11, the needle valve 5-10 gradually descends, and finally closes the spray hole 5-13, stopping the injection of methanol; thus, within a period of oil supply, the dual-fuel mixed injection of diesel igniting methanol is realized.

[0032] The present application adopts an electric control single pump to supply oil, ensures stable delivery of diesel under high pressure conditions, simultaneously serves as a control medium for methanol injection, reduces direct contact of methanol with the injector material, and reduces the corrosion risk; through independent methanol supply pipelines and electric control injectors, precise injection of methanol is realized, the timing and flow of methanol injection are indirectly controlled by the diesel delivery system, and the injection process is further optimized. In addition, by using the cooperation of the electric control single pump oil supply and the electric control injector, the multi-solenoid valve cooperative control technology is adopted, on the one hand, the large-flow injection of diesel and methanol two fuels is realized, on the other hand, through the control of the opening timing and injection parameters of the solenoid valve, the efficient mixing and accurate control of diesel and methanol are realized, which not only can improve the flexibility and response speed of the injection system, but also can reduce the complexity and cost of the system.

Claims

1. A high-flow dual-fuel injection system with coordinated control of multiple solenoid valves, characterized by: It includes an electronically controlled unit pump, a common rail pipe, a diaphragm pressure regulator, a diesel fuel tank, a methanol storage tank, a diesel-methanol integrated injector, and an electronic control unit. The diesel fuel tank is connected to the oil inlet of the electronically controlled unit pump through a fuel filter, and the oil outlet of the electronically controlled unit pump is connected to the diaphragm pressure regulator. The oil return port of the electronically controlled unit pump, the diesel fuel tank, and the diaphragm pressure regulator are connected through a first three-way valve. The methanol storage tank is connected to the common rail pipe through a delivery pump. The diesel-methanol integrated injector is respectively connected to the diaphragm pressure regulator, the common rail pipe, the diesel fuel tank, and the methanol storage tank. The electronic control unit is respectively connected to the electronically controlled unit pump, the common rail pipe, the delivery pump, the diesel-methanol integrated injector, and the diaphragm pressure regulator through signal pipelines.

2. The high-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 1 is characterized by: The diesel-methanol integrated injector includes a connected methanol injection unit and a diesel injection unit, a No. 1 diesel oil return port is provided on the top of the methanol injection unit, a methanol solenoid valve assembly is provided below the No. 1 diesel oil return port, the methanol solenoid valve assembly includes a first compression type return spring and a first control armature below it, a first solenoid valve control electromagnet and a first solenoid valve control coil are provided outside the first compression type return spring, a first needle valve control chamber is provided below the first control armature, a first return oil throttling hole is provided on the upper part of the first needle valve control chamber, the first return oil throttling hole is sealed by a first ball valve installed at the bottom of the first control armature, a first diesel oil inlet is provided on the side of the methanol injection unit, the first diesel oil inlet is connected to the first needle valve control chamber through the first oil inlet throttling hole, a first needle valve is provided below the first needle valve control chamber, a methanol spray hole is provided below the first needle valve, a first needle valve return spring is provided outside the first needle valve, a methanol storage chamber and a methanol upper chamber are provided at the lower part of the methanol injection unit, and the methanol storage chamber is connected to the common rail pipe and the methanol spray hole respectively.

3. The high-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 2 is characterized by: A No. 2 diesel oil return port is set on the top of the diesel injection unit, and a diesel solenoid valve assembly is set below the No. 2 diesel oil return port. The diesel solenoid valve assembly includes a second compression type return spring and a second control armature below it. A second solenoid valve control electromagnet and a second solenoid valve control coil are set outside the second compression return spring. A second needle valve control chamber is set below the second control armature. A second return oil throttling hole is opened on the upper part of the second needle valve control chamber. The second return oil throttling hole is sealed by a second ball valve installed at the bottom of the second control armature. A second diesel oil inlet is set on the side of the diesel injection unit. The second diesel oil inlet is connected to the second needle valve control chamber through the second oil inlet throttling hole. A second needle valve is set below the second needle valve control chamber. A diesel spray hole is set below the second needle valve. A second needle valve return spring is sleeved on the outside of the second needle valve. An oil storage tank is set on the outside of the second needle valve, and the oil storage tank is connected to the second diesel oil inlet through a diesel inlet pipeline.

4. The high-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 3 is characterized by: The No. 1 diesel return port, the No. 2 diesel return port and the diesel tank are connected through the second three-way valve; the first diesel inlet, the second diesel inlet and the diaphragm type pressure regulator are connected through the third three-way valve; the methanol upper chamber, the common rail pipe and the methanol storage chamber are connected through the fourth three-way valve.

5. The high-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 1 is characterized by: The diaphragm type pressure stabilizer includes a shell, a fuel inlet and an oil return valve are arranged on both sides of the shell, an elastic diaphragm is installed inside the shell, one side of the elastic diaphragm is a pressure stabilizing chamber, the pressure stabilizing chamber is connected to the fuel inlet and the oil return port respectively, a valve is arranged on the other side of the elastic diaphragm, and a compression spring is installed between the elastic diaphragm and the valve.

6. The high-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 1 is characterized by: The methanol in the methanol storage tank flows into the common rail pipe through the delivery pump and then into the methanol storage chamber through the delivery pipeline. The low-pressure diesel fuel in the diesel tank first passes through the fuel filter and enters the single-unit pump through the oil inlet of the electronically controlled single-unit pump. After the electronically controlled single-unit pump receives the signal from the electronic control unit, the high-pressure diesel fuel from the electronically controlled single-unit pump enters the diaphragm-type pressure regulator. The high-pressure diesel fuel enters the pressure regulating chamber from the pressure regulator inlet. When the high-pressure diesel fuel flows through the elastic diaphragm, the diaphragm senses the pressure change. When the pressure exceeds the set value, the elastic diaphragm deforms and pushes the compression spring. The valve adjusts its opening according to the movement of the elastic diaphragm to control the fuel flow. When the pressure is too high, the return valve automatically opens to release the excess pressure. After the pressure is stabilized by the pressure stabilizer, the high-pressure diesel is diverted through the three-way valve. Part of it flows to the methanol injection unit, enters from the first diesel inlet, enters the first needle valve control chamber through the first oil inlet throttle hole, and acts on the first needle valve through the first needle valve return spring, so that the first needle valve remains stationary; the other part flows to the diesel injection unit, and flows into the second needle valve control chamber and the oil tank respectively through the second diesel inlet pipeline. Under the combined action of the pressure in the second needle valve control chamber and the preload force of the needle valve spring, the second needle valve remains stationary.

7. A high-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 1, The invention is characterized in that: during a fuel supply period of the electronically controlled single pump, when the diesel solenoid valve assembly of the diesel injection unit is in a non-operating state and the first solenoid valve control coil in the methanol injection unit begins to be energized, current passes through the first solenoid valve control coil to generate electromagnetic force, which attracts the first control armature to move upward. The movement of the first control armature drives the first ball valve to open the first oil return throttle hole. As the first oil return throttle hole opens, the pressure in the first needle valve control chamber drops, causing the first needle valve to overcome the force of the first needle valve return spring and move upward, thereby opening a passage between the methanol storage chamber and the spray hole chamber, and finally spraying the methanol out through the spray hole. The diesel injection unit remains in a closed state because the diesel solenoid valve assembly is not working, and no diesel injection is carried out; when the diesel solenoid valve assembly of the diesel injection unit is energized and working, and the first solenoid valve control coil in the methanol injection unit is not energized, the first needle valve on the methanol injection side continues to maintain its initial static state, and methanol is not injected. The diesel solenoid valve assembly is energized, and the return oil channel of the second needle valve control chamber is opened. The pressure in the second needle valve control chamber drops, causing the needle valve to open, and high-pressure diesel is ejected from the diesel spray hole, realizing the separate supply of high-pressure diesel.

8. A large-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 1 is characterized in that: during an oil supply period of the electronically controlled single pump, the diesel solenoid valve assembly in the diesel injection unit is first energized to work, the first solenoid valve control coil is in an unpowered state at this time, and the return oil channel of the second needle valve control chamber is opened, so that the second needle valve is opened, and high-pressure diesel is sprayed out through the diesel spray hole; after the diesel solenoid valve assembly is powered off, the high-pressure diesel stops spraying, the first solenoid valve control coil starts to be energized, and the current flows through the coil to generate electromagnetic force, attracting the first control armature to move upward, the first ball valve opens the first return oil throttle hole, and the pressure in the first needle valve control chamber drops, causing the first needle valve to overcome the force of the first needle valve return spring and move upward, opening the channel between the methanol storage chamber and the spray hole chamber, and realizing large-flow injection of methanol through the methanol spray hole (5-13).

9. The high-flow dual-fuel injection system with coordinated control of multiple solenoid valves according to claim 1 is characterized by: At the end of oil supply, the control coil of the first solenoid valve is de-energized, and the first control armature returns to its initial position under the action of the first compression return spring. The first ball valve reseals the first oil return throttle hole, and the oil pressure in the control chamber of the first needle valve increases accordingly. Cooperating with the first needle valve return spring, the first needle valve descends, closing the methanol spray hole and stopping the injection of methanol.

Images