A piston-type booster pump and a fuel injection system based on a dual-solenoid valve booster pump with flexible and variable injection patterns.

Abstract

The purpose of this invention is to provide a piston-type booster pump and a fuel injection system based on a dual-solenoid valve booster pump with a flexible and variable injection pattern, belonging to the field of engine technology. Fuel is pressurized by an electronically controlled unit pump and enters the high-pressure common rail. The piston-type booster pump can further pressurize the pressurized fuel, thereby changing the injection pressure of the injector and achieving a variable fuel injection pattern. When only one booster pump solenoid valve is open, the piston-type booster pump has a long booster response time and a slow increase in injection rate. When both booster pump solenoid valves are open simultaneously, the piston-type booster pump has a short booster response time and a fast increase in injection rate. The electronic control unit achieves flexible control of the injection pattern by coordinating the opening and closing sequence of the two booster pump solenoid valves, the electronically controlled unit pump solenoid valve, and the injector solenoid valve.

Description

Technical Field

[0001] The present invention relates to an engine, specifically a fuel injection device for an engine. Background Technology

[0002] With the increasing global energy demand and increasingly stringent emission regulations, efficient, clean, and low-carbon combustion modes have become the core issue in the development of internal combustion engine technology. This also places higher demands on fuel injection systems. Higher injection pressure, faster response speed, and more flexible and controllable injection patterns will be the future development trends of engine fuel injection systems. The flexibility and variability of fuel injection patterns can solve the problem that traditional trapezoidal injection patterns cannot flexibly adjust the injection quantity during the injection process, and can further realize more advanced combustion modes to improve engine performance. Summary of the Invention

[0003] The purpose of this invention is to provide a piston-type booster pump capable of shaping injection rate curves of different shapes and achieving flexible adjustment of the injection pattern, as well as a fuel injection system based on a dual-solenoid valve booster pump with a flexible and variable injection pattern.

[0004] The objective of this invention is achieved as follows: This invention discloses a piston-type booster pump, characterized by comprising a fuel inlet block, a booster pump body, a No. 1 booster pump solenoid valve, and a No. 2 booster pump solenoid valve. The fuel inlet block is fixed to the top of the booster pump body, and the No. 1 and No. 2 booster pump solenoid valves are respectively fixed to the sides of the booster pump body. The fuel inlet block provides a booster pump inlet, and the bottom of the booster pump body provides a booster pump outlet. A booster piston is installed inside the booster pump body, and a booster pump check valve is provided on the top of the booster piston. A control chamber inlet throttling orifice and an internal flow channel are respectively provided inside the booster piston, with the internal flow channel located below the booster pump check valve. The upper part of the booster piston is the large end, and the lower part of the booster piston is the small end. The lower end face of the large end forms a booster pump control chamber with the booster pump body. Holes are drilled on both sides of the booster pump control chamber. The first side hole cooperates with the No. 1 booster pump solenoid valve, and the second side hole cooperates with the No. 2 booster pump solenoid valve. The lower end face of the small end forms a booster chamber with the booster pump body. A booster piston return spring is sleeved on the lower end of the small end. The booster pump inlet is connected to the control chamber inlet throttling orifice and the booster piston inner flow channel. The control chamber inlet throttling orifice is connected to the booster pump control chamber, the booster piston inner flow channel is connected to the booster chamber, and the booster chamber is connected to the booster pump outlet.

[0005] The piston-type booster pump of the present invention may further include: 1. The booster pump body is equipped with a No. 1 booster pump return channel, a No. 1 booster pump return port, a No. 2 booster pump return channel, and a No. 2 booster pump return port. The No. 1 booster pump solenoid valve has a No. 1 control chamber return throttling orifice, and the No. 2 booster pump solenoid valve has a No. 2 control chamber return throttling orifice. The No. 1 booster pump return channel connects to the first side hole and the No. 1 control chamber return throttling orifice, and the No. 2 booster pump return channel connects to the second side hole and the No. 2 control chamber return throttling orifice. The No. 1 booster pump solenoid valve is connected to and controls the No. 1 sealing ball. When the solenoid valve of booster pump No. 1 is not energized, sealing ball No. 1 seals the return throttle orifice of control chamber No. 1. When the solenoid valve of booster pump No. 1 is energized, sealing ball No. 1 opens the return throttle orifice of control chamber No. 1, making it connected to the return port of booster pump No. 1. Solenoid valve of booster pump No. 2 is connected to and controls sealing ball No. 2. When the solenoid valve of booster pump No. 2 is not energized, sealing ball No. 2 seals the return throttle orifice of control chamber No. 2. When the solenoid valve of booster pump No. 2 is energized, sealing ball No. 2 opens the return throttle orifice of control chamber No. 2, making it connected to the return port of booster pump No. 2.

[0006] 2. The diameters of the return throttling orifice in control chamber 1 and the return throttling orifice in control chamber 2 are larger than the diameter of the inlet throttling orifice in control chamber 2.

[0007] 3. When neither the No. 1 nor the No. 2 booster pump solenoid valve is driven at all, trapezoidal base pressure injection is achieved; when both the No. 1 and No. 2 booster pump solenoid valves are driven at all times, ideal boot-shaped injection is achieved; when one of the No. 1 or No. 2 booster pump solenoid valves is driven during injection, boot-shaped injection with a slower second-stage injection rate is achieved; when one of the No. 1 or No. 2 booster pump solenoid valves is driven at the start of injection, triangular or wedge-shaped injection is achieved; when both the No. 1 and No. 2 booster pump solenoid valves are driven before injection to complete pressurization, high-pressure injection is achieved.

[0008] This invention relates to a fuel injection system based on a flexible and variable injection pattern using a dual-electromagnetic-valve booster pump. The system is characterized by comprising a fuel tank, an electronically controlled unit pump, an injector, a high-pressure common rail, and a piston-type booster pump as described above. The electronically controlled unit pump includes an electronically controlled unit pump solenoid valve, an electronically controlled unit pump inlet, an electronically controlled unit pump return port, and an electronically controlled unit pump outlet. The injector includes an injector solenoid valve, an injector inlet, and an injector return port. Fuel flows from the fuel tank to the electronically controlled unit pump inlet, and under the control of the electronically controlled unit pump solenoid valve, enters the high-pressure common rail or flows back to the fuel tank through the electronically controlled unit pump return port. The high-pressure common rail is connected to the booster pump inlet. Fuel flows into the injector inlet via the booster pump or flows back to the fuel tank under the control of booster pump solenoid valves 1 and 2. Fuel in the injector is injected under the control of the injector solenoid valve or flows back to the fuel tank through the injector return port.

[0009] The fuel injection system based on the flexible and variable injection pattern of the dual-electromagnetic valve booster pump of the present invention may further include: 1. Install rail pressure sensors on the high-pressure common rail.

[0010] 2. It also includes an electronic control unit, which is connected to the rail pressure sensor, the solenoid valve of the electronic control unit pump, the solenoid valve of the injector, the solenoid valve of booster pump No. 1, and the solenoid valve of booster pump No. 2.

[0011] The advantages of this invention are: 1. By adding a piston-type booster pump to the fuel system, the injection pattern can be changed by altering the injection pressure. This requires minimal modification to the original system and is easy to implement.

[0012] 2. The design of the dual solenoid valves in the booster pump is used to regulate the descent speed of the booster piston and control the rate of change of injection pressure, thereby shaping different injection rate curves and achieving flexible and adjustable injection patterns, which is conducive to further improving engine performance. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a front view of a piston booster pump. Figure 3 This is a left-side view of a piston booster pump. Figure 4 This is a cross-sectional view and a partial enlarged view of the left side of the piston booster pump along the AA direction.

[0014] Figure reference numerals: 1. Piston booster pump; 2. Injector; 3. Electronic control unit; 4. Fuel tank; 5. Filter; 6. Electronically controlled unit pump; 7. High-pressure common rail; 1-1. Booster pump inlet; 1-2. Solenoid valve for booster pump No. 1; 1-3. Return port for booster pump No. 1; 1-4. Solenoid valve for booster pump No. 2; 1-5. Return port for booster pump No. 2; 1-6. Booster piston; 1-7. Booster pump check valve; 1-8. Booster pump control chamber; 1-9. Booster piston return spring; 1-10. Return channel for booster pump No. 1; 1- 11; No. 1 sealing ball 1-12; No. 1 booster pump return flow channel 1-13; No. 1 sealing ball 1-14; booster chamber 1-15; control chamber return throttle orifice 1-16; control chamber inlet throttle orifice 1-7-1; booster piston inner flow channel 1-7-2; injector inlet 2-1; injector return port 2-2; injector solenoid valve 2-3; electric control unit pump inlet 6-1; electric control unit pump return port 6-2; electric control unit pump solenoid valve 6-3; electric control unit pump outlet 6-4; rail pressure sensor 7-1. Detailed Implementation

[0015] The invention will now be described in more detail with reference to the accompanying drawings: Implementation method 1, combined with Figure 2-4The piston-type booster pump 1, from top to bottom, includes a booster pump inlet 1-1, a booster piston 1-7, a booster piston return spring 1-10, and a booster pump outlet 1-6. The booster piston 1-7 contains a booster pump check valve 1-8, a control chamber inlet throttling orifice 1-7-1, and an internal flow channel 1-7-2. The booster pump check valve 1-8 is fixed to the booster piston 1-7 by threads. The space between the lower end face of the large end of the booster piston 1-7 and the booster pump body is the booster pump control chamber 1-9, and the space between the lower end face of the small end of the booster piston and the booster pump body is the booster chamber 1-15. The booster pump control chamber 1-9 has two sides... Drill holes; the left hole connects to the return flow channel 1-11 of booster pump 1, and the right hole connects to the return flow channel 1-13 of booster pump 2. The piston-type booster pump 1 has a booster pump solenoid valve 1-2 on the left and a booster pump solenoid valve 1-4 on the right. A portion of the high-pressure fuel entering from the booster pump inlet 1-1 enters the booster pump control chamber 1-9 through the control chamber inlet throttling orifice 1-7-1, while the other portion enters the booster chamber 1-15 after passing through the booster pump check valve 1-8 and the booster piston inner flow channel 1-7-2. The fuel entering the booster chamber 1-15 then enters the injector through the booster pump outlet 1-6. When solenoid valve 1-2 is energized, sealing ball 1-12 will open, connecting the return flow channel 1-11 and return port 1-3 of booster pump 1. Fuel in booster pump control chamber 1-9 will flow back from return port 1-3 to fuel storage tank 4. When solenoid valve 2-4 is energized, sealing ball 1-14 will open, connecting the return flow channel 1-13 and return port 1-5 of booster pump 2. Fuel in booster pump control chamber 1-9 will flow back from return port 1-5 to fuel storage tank 4. Because the diameter of the return throttling orifice 1-16 in the control chamber is larger than the control... The orifice diameter of the throttling orifice at the inlet of the chamber is 1-7-1. Therefore, after the booster pump is solenoidally turned on, the pressure in the booster pump control chamber 1-9 will continuously decrease. Under the action of the pressure difference, the booster piston 1-7 moves down against the spring force of the booster piston return spring 1-10, and performs secondary boosting on the high-pressure fuel in the booster chamber 1-15. When the two booster pump solenoid valves are closed at the same time, the pressure in the booster pump control chamber 1-9 will continuously increase until it reaches the pressure level of the fuel in the high-pressure common rail 7. At this time, the hydraulic pressure on the booster piston 1-7 is balanced, and the booster piston 1-7 will move up and reset under the action of the booster piston return spring 1-10.

[0016] Implementation Method 2: Based on Implementation Method 1, such as... Figure 1As shown, the present invention discloses a fuel injection system based on a dual-electromagnetic-valve booster pump with flexible variable injection pattern, comprising a piston-type booster pump 1 equipped with dual electromagnetic valves, an injector 2, an electronic control unit 3, a fuel storage tank 4, a filter 5, an electronically controlled unit pump 6, and a high-pressure common rail 7. When the electronically controlled unit pump solenoid valve 6-3 is not energized, the fuel returns to the fuel storage tank 4 through the electronically controlled unit pump return port 6-2, without pressurizing the fuel. When the electronically controlled unit pump solenoid valve 6-3 is energized, the electronically controlled unit pump 6 pressurizes the fuel in the fuel storage tank 4. The fuel is pressurized and delivered to the high-pressure common rail. When the solenoid valves 1-2 and 1-4 of booster pump 1 are energized, the fuel in the booster pump control chamber returns to the fuel storage tank 4 through the return ports 1-3 and 1-5 of booster pump 1 and 2. The booster piston moves down, providing secondary pressurization to the high-pressure fuel. The high-pressure common rail is equipped with a rail pressure sensor 7-1. After being filtered by filter 5, the fuel from fuel storage tank 4 enters the inlet 6-1 of the electronically controlled unit pump. After being pressurized by the electronically controlled unit pump 6, the high-pressure fuel is... The high-pressure fuel in the common rail 7 enters from the outlet 6-4 of the electronically controlled unit pump. The high-pressure fuel in the common rail 7 enters the piston-type booster pump 1 through the booster pump inlet 1-1, and then enters the injector 2 through the injector inlet 2-1 via the booster pump outlet 1-6. The piston-type booster pump 2 can either re-pressurize the high-pressure fuel or maintain its pressure, thus achieving variable fuel injection patterns. During the injection process of the injector 2, fuel will flow back to the fuel storage tank 3 from the injector return port 2-2. The No. 1 booster pump solenoid valve 1-2, the No. 2 booster pump solenoid valve 1-4, the rail pressure sensor 7-1, the injection solenoid valve 2-3, and the electronically controlled unit pump solenoid valve 6-3 are all connected to the electronic control unit 3 via signal paths. The electronic control unit 3 can receive and send signals through these signal paths. By receiving the signal from the rail pressure sensor 7-1, the electronic control unit 3 coordinates the control of the No. 1 booster pump solenoid valve 1-2, the No. 2 booster pump solenoid valve 1-4, the electronically controlled unit pump solenoid valve 6-3, and the injector solenoid valve 2-3 to achieve flexible control of the injection patterns.

[0017] Implementation Method 3: Based on Implementation Methods 1 and 2, driving either the No. 1 booster pump solenoid valve 1-2 or the No. 2 booster pump solenoid valve 1-4 alone will result in a small backflow rate, a slow decrease in pressure in the booster pump control chamber 1-9, and a slow downward movement of the booster piston 1-7, leading to a slow increase in injection pressure and injection rate. However, when both the No. 1 booster pump solenoid valve 1-2 and the No. 2 booster pump solenoid valve 1-4 are driven simultaneously, the backflow rate is larger, the pressure in the booster pump control chamber 1-9 decreases rapidly, the booster piston 1-7 moves downward quickly, the injection pressure increases rapidly, and the injection rate increases quickly. During the injection process, by controlling the opening and closing sequence of the No. 1 booster pump solenoid valve 1-2, the No. 2 booster pump solenoid valve 1-4, and the injection solenoid valve 2-3, flexible control of the injection pattern can be achieved.

[0018] In the traditional trapezoidal base pressure injection mode, the two booster pump solenoid valves are not driven throughout the injection process of injector 2; in the ideal shoe-shaped injection mode, both booster pump solenoid valves are driven during the injection process of injector 2; in the shoe-shaped injection mode where the second-stage injection rate increases more slowly, one booster pump solenoid valve is driven during the injection process of injector 2; in the triangular or wedge-shaped injection mode, one booster pump solenoid valve is driven at the beginning of injection; in the high-boost injection mode, both booster pump solenoid valves are driven to complete the boost before injection; other injection modes can be achieved by controlling the driving sequence of booster pump solenoid valves 1-2, 2-4, and injection solenoid valves 2-3.

Claims

1. A piston-type booster pump, characterized in that: The system includes a fuel inlet block, a booster pump body, a No. 1 booster pump solenoid valve, and a No. 2 booster pump solenoid valve. The fuel inlet block is fixed to the top of the booster pump body. The No. 1 and No. 2 booster pump solenoid valves are respectively fixed to the sides of the booster pump body. The fuel inlet block provides the booster pump inlet, and the booster pump body has a booster pump outlet at the bottom. A booster piston is installed inside the booster pump body, and a booster pump check valve is installed on the top of the booster piston. A control chamber inlet throttling orifice and an internal flow channel are respectively provided inside the booster piston. The internal flow channel is located below the booster pump check valve. The upper part of the booster piston... The large end is the part of the booster piston, and the small end is the part below it. The lower end face of the large end forms a booster pump control chamber with the booster pump body. The booster pump control chamber is perforated on both sides. The first side hole is matched with the No. 1 booster pump solenoid valve, and the second side hole is matched with the No. 2 booster pump solenoid valve. The lower end face of the small end forms a booster chamber with the booster pump body. The lower end of the small end is fitted with a booster piston return spring. The booster pump inlet is connected to the control chamber inlet throttling orifice and the booster piston inner flow channel. The control chamber inlet throttling orifice is connected to the booster pump control chamber, the booster piston inner flow channel is connected to the booster chamber, and the booster chamber is connected to the booster pump outlet.

2. A piston-type booster pump according to claim 1, characterized in that: boosting... The pump body is equipped with a return flow channel for booster pump No. 1, a return flow port for booster pump No. 1, a return flow channel for booster pump No. 2, and a return flow port for booster pump No.

2. The solenoid valve for booster pump No. 1 has a return throttling orifice for control chamber No. 1, and the solenoid valve for booster pump No. 2 has a return throttling orifice for control chamber No.

2. The return flow channel for booster pump No. 1 connects to the first side hole and the return throttling orifice for control chamber No. 1, and the return flow channel for booster pump No. 2 connects to the second side hole and the return throttling orifice for control chamber No.

2. The solenoid valve for booster pump No. 1 connects to and controls the sealing ball No.

1. When the booster pump solenoid valve is not energized, the No. 1 sealing ball seals the No. 1 control chamber return throttle orifice. When the No. 1 booster pump solenoid valve is energized, the No. 1 sealing ball opens the No. 1 control chamber return throttle orifice, making it connected to the No. 1 booster pump return port. The No. 2 booster pump solenoid valve is connected to and controls the No. 2 sealing ball. When the No. 2 booster pump solenoid valve is not energized, the No. 2 sealing ball seals the No. 2 control chamber return throttle orifice. When the No. 2 booster pump solenoid valve is energized, the No. 2 sealing ball opens the No. 2 control chamber return throttle orifice, making it connected to the No. 2 booster pump return port.

3. A piston-type booster pump according to claim 2, characterized in that: The diameters of the return throttling orifice in control chamber 1 and the return throttling orifice in control chamber 2 are larger than the diameter of the inlet throttling orifice in control chamber.

4. A piston-type booster pump according to claim 1, characterized in that: When neither of the No. 1 nor the No. 2 booster pump solenoid valves is driven throughout the entire process, trapezoidal base pressure injection is achieved; when both of the No. 1 and No. 2 booster pump solenoid valves are fully driven throughout the entire process, ideal boot-shaped injection is achieved; when one of the No. 1 or No. 2 booster pump solenoid valves is driven during the injection process, boot-shaped injection with a slower second-stage injection rate is achieved; when one of the No. 1 or No. 2 booster pump solenoid valves is driven at the beginning of injection, triangular or wedge-shaped injection is achieved; when both of the No. 1 and No. 2 booster pump solenoid valves are driven before injection to complete pressurization, high-pressure injection is achieved.

5. A fuel injection system based on a dual-solenoid valve booster pump with flexible and variable injection characteristics, characterized by: The system includes a fuel storage tank, an electronically controlled unit pump, an injector, a high-pressure common rail, and a piston-type booster pump as described in claim 1. The electronically controlled unit pump includes an electronically controlled unit pump solenoid valve, an electronically controlled unit pump inlet, an electronically controlled unit pump return port, and an electronically controlled unit pump outlet. The injector includes an injector solenoid valve, an injector inlet, and an injector return port. Fuel flows from the fuel storage tank to the electronically controlled unit pump inlet and enters the high-pressure common rail or flows back to the fuel storage tank through the electronically controlled unit pump return port under the control of the electronically controlled unit pump solenoid valve. The high-pressure common rail is connected to the booster pump inlet. Fuel flows into the injector inlet via the booster pump or flows back to the fuel storage tank under the control of booster pump solenoid valves 1 and 2. Fuel in the injector is injected under the control of the injector solenoid valve or flows back to the fuel storage tank through the injector return port.

6. The fuel injection system based on a dual-electromagnetic valve booster pump with flexible variable injection pattern according to claim 5, characterized in that: A rail pressure sensor is installed on the high-pressure common rail.

7. The fuel injection system based on a dual-electromagnetic valve booster pump with flexible variable injection pattern according to claim 6, characterized in that: It also includes an electronic control unit, which is connected to the rail pressure sensor, the solenoid valve of the electronically controlled unit pump, the solenoid valve of the injector, the solenoid valve of booster pump No. 1, and the solenoid valve of booster pump No. 2.

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