A high-stability methanol injector based on a suspended low-leakage assembly

Abstract

The present application aims to provide a high-stability methanol injector based on a suspended low-leakage assembly, belonging to the field of engines. The low-leakage valve assembly body is installed with a suspended low-leakage assembly, the intermediate body and the nozzle body are installed with a multi-stage needle valve lift assembly, the multi-stage needle valve lift assembly comprises a needle valve, a storage alcohol cavity is formed between the needle valve and the nozzle body, a high-pressure pipeline joint is installed on the side of the two-stage lift electromagnetic control valve body, an alcohol inlet pipeline is arranged in the high-pressure pipeline joint, and the alcohol inlet pipeline passes through the two-stage lift electromagnetic control valve body, the one-stage lift electromagnetic control valve body, the low-leakage valve assembly body, the intermediate body and the nozzle body and is connected with the storage alcohol cavity. The present application realizes rapid pressure relief of the injector control chamber through the suspended low-leakage assembly, significantly improves the needle valve rising acceleration, and further improves the methanol injection stability, while reducing the alcohol return amount during the injection process; combined with the multi-stage needle valve lift assembly, the high-stability methanol boot-shaped injection rate can be realized synchronously.

Description

Technical Field

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

[0002] Traditional petroleum-based internal combustion engines are increasingly unable to meet stringent emission regulations and environmental requirements. Developing clean, low-carbon or zero-carbon fuels is key to reducing environmental pollution and solving emission problems. Compared with fuels such as hydrogen and ammonia, methanol is considered one of the most promising clean alternative fuels due to its advantages such as low cost, ease of preparation, and convenient storage and transportation.

[0003] The design and development of methanol fuel injectors is crucial for the widespread application of methanol fuel in internal combustion power. Due to fluctuations in internal fuel pressure, when the needle valve's upward acceleration is low, it cannot open fully quickly, resulting in significant inconsistencies in the opening timing, upward phase, and downward phase, leading to poor methanol injection stability. Furthermore, the low calorific value of methanol results in a longer injection cycle, leading to greater methanol leakage. Summary of the Invention

[0004] The purpose of this invention is to provide a highly stable methanol injector based on a suspended low-leakage component that can significantly improve the acceleration of the needle valve and reduce the inconsistency of transient methanol injection and methanol leakage.

[0005] The objective of this invention is achieved as follows: This invention discloses a highly stable methanol injector based on a suspended low-leakage component, characterized by comprising, from top to bottom, a first-stage lift-up electromagnetic control valve body, a second-stage lift-up electromagnetic control valve body, a low-leakage valve assembly body, an intermediate body, and a nozzle body. The first-stage lift-up electromagnetic control valve body houses a first-stage lift-up electromagnetic control valve assembly, with a first-stage methanol outlet throttling orifice at its bottom. The second-stage lift-up electromagnetic control valve body houses a second-stage lift-up electromagnetic control valve assembly, with a second-stage methanol outlet throttling orifice at its bottom. The low-leakage valve assembly body houses a suspended low-leakage component. The intermediate body and nozzle body house multi-stage needle valve lift-up components, each including a needle valve. A methanol storage chamber is formed between the needle valve and the nozzle body. A high-pressure pipeline connector is installed on the side of the second-stage lift-up electromagnetic control valve body, with a methanol inlet pipeline inside. The methanol inlet pipeline passes through the second-stage lift-up electromagnetic control valve body, the first-stage lift-up electromagnetic control valve body, the low-leakage valve assembly body, the intermediate body, and the nozzle body, and connects to the methanol storage chamber.

[0006] The present invention may also include: 1. The suspended low-leakage assembly includes a suspended low-leakage valve, a suspended low-leakage valve reset spring installed above the suspended low-leakage valve, a suspended throttling control orifice opened at the top of the suspended low-leakage valve, a first control chamber opened inside the suspended low-leakage valve, the suspended throttling control orifice connecting the first control chamber and the first-stage alcohol outlet throttling orifice respectively, a first control chamber alcohol inlet control ring cavity is formed between the suspended low-leakage valve and the low-leakage valve assembly body, the first control chamber alcohol inlet control ring cavity is connected to the alcohol inlet pipeline, under the action of the pre-tightening force of the suspended low-leakage valve reset spring, the suspended low-leakage valve is located at the lower dead point, and the opening of the first control chamber alcohol inlet control ring cavity is in the maximum state.

[0007] 2. The multi-stage needle valve lift assembly further includes a lift control valve block. The top of the needle valve and the intermediate body form a needle valve cavity. A first alcohol inlet throttling orifice and a second alcohol inlet throttling orifice are provided in the intermediate body. The needle valve cavity is connected to the first control chamber and the first alcohol inlet throttling orifice, respectively. The first alcohol inlet throttling orifice is also connected to the alcohol inlet control ring cavity of the first control chamber. The needle valve is provided with a needle valve protrusion. The lift control valve block is sleeved on the outside of the needle valve. A needle valve return spring is sleeved on the needle valve. The needle valve return spring is located between the needle valve protrusion and the intermediate body above it. The lift control valve block is sleeved on the outside of the needle valve. The lift control valve block return spring is located between the lift control valve block and the intermediate body above it. The lift control valve block and the intermediate body form a second control chamber, which is connected to the second alcohol inlet throttling orifice and the second alcohol outlet throttling orifice. Under the action of the lift control valve block return spring and hydraulic pressure, the lift control valve block sits on the nozzle body. Under the action of the needle valve return spring and hydraulic pressure, the needle valve cooperates with the nozzle body to form a sealing ring. In the non-working state, there is a gap between the lift control valve block and the needle valve.

[0008] 3. The diameter of the orifice in the suspension throttling control is larger than the diameter of the first alcohol inlet throttling orifice.

[0009] 4. In the small-lift injection mode, current is supplied to the first-stage lift solenoid control valve assembly, and the second-stage lift solenoid control valve assembly is de-energized. The first-stage methanol outlet throttling orifice opens, and methanol flows out of the first control chamber through the suspension throttling control orifice. The hydraulic pressure at the lower end of the suspension low-leakage valve overcomes the preload of the suspension low-leakage valve reset spring, causing the suspension low-leakage valve to lift upward. The methanol inlet control ring of the first control chamber closes, reducing the flow rate of methanol into the first control chamber from the first methanol inlet throttling orifice. The hydraulic pressure at the lower end of the suspension low-leakage valve decreases. When it is less than the preload of the suspension low-leakage valve reset spring, the suspension low-leakage valve falls back until the hydraulic pressure on the suspension low-leakage valve balances the spring preload. The suspension low-leakage valve stabilizes at a fixed opening degree and stops moving when the needle valve rises to contact the lift control valve block.

[0010] 5. In the high-lift injection mode, current is applied to the secondary lift solenoid control valve assembly, the secondary methanol outlet throttle orifice opens, methanol flows out of the second control chamber through the methanol outlet throttle orifice, the fuel pressure in the second control chamber decreases, the lift control valve block rises against the preload force of the lift control valve block return spring until it reaches the maximum lift, current is applied to the primary lift solenoid control valve assembly, the primary methanol outlet throttle orifice opens, the pressure in the primary control chamber is released, the hydraulic pressure at the upper end of the needle valve decreases, the needle valve rises against the preload force of the needle valve return spring until it reaches the maximum lift.

[0011] 6. In boot-type injection mode, the first-stage lift solenoid control valve assembly is energized first. Under the action of the suspended low-leakage component, the methanol pressure in the first control chamber decreases, and the needle valve overcomes the spring preload and lifts upward, realizing a small amount of methanol injection with the needle valve opening at a small lift. Then, the second-stage lift solenoid control valve assembly is energized, and the methanol pressure in the second control chamber decreases. The needle valve and the lift control valve block together overcome the preload of the lift control valve block reset spring and lift upward until the maximum lift is reached.

[0012] The advantages of this invention are as follows: This invention achieves rapid depressurization of the methanol fuel injector control chamber through a suspended low-leakage component, significantly increasing the acceleration of the needle valve's upward movement. This reduces the inconsistency between the needle valve's opening moment and the upward movement phase, improving methanol injection stability. Simultaneously, the suspended low-leakage component also reduces methanol leakage during injection, achieving low-leakage and highly stable methanol injection. Furthermore, by matching the first-stage lift solenoid control valve assembly, the second-stage lift solenoid control valve assembly, the multi-stage needle valve lift assembly, and the suspended low-leakage component, this invention allows for flexible adjustment of small needle valve lift injection mode, large needle valve lift injection mode, and shoe-type injection mode, while ensuring high methanol injection stability in each injection mode. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 A schematic diagram of the structure of a suspended low-leakage component; Figure 3 This is a schematic diagram of the structure of a multi-stage needle valve lift assembly.

[0014] Figure reference numerals: 1: Second-stage lift solenoid control valve body; 2: Second-stage lift solenoid control valve assembly; 3: Injector body locking nut; 4: First-stage lift solenoid control valve body; 5: First-stage lift solenoid control valve assembly; 6: Suspension low-leakage assembly; 7: Multi-stage needle valve lift assembly; 8: Nozzle body locking nut; 9: High-pressure pipeline connector.

[0015] 601: Suspension low-leakage valve reset spring; 602: Suspension low-leakage valve; 603: Low-leakage component body; 604: First control chamber; 605: First control chamber alcohol inlet control ring cavity; 606: Suspension throttling control orifice.

[0016] 701: Needle valve; 702: Second alcohol inlet throttling orifice; 703: Lift control valve block return spring; 704: Lift control valve block; 705: Nozzle body; 706: Needle valve return spring; 707: Second control chamber; 708: Intermediate body; 709: First alcohol inlet throttling orifice. Detailed Implementation

[0017] The invention will now be described in more detail with reference to the accompanying drawings: Implementation method 1, combined with Figure 1-3 This embodiment consists of a two-stage lift solenoid control valve body 1, a two-stage lift solenoid control valve assembly 2, an injector body locking nut 3, a first-stage lift solenoid control valve body 4, a first-stage lift solenoid control valve assembly 5, a suspension low-leakage assembly 6, a multi-stage needle valve lift assembly 7, a nozzle body 705 locking nut 8, and a high-pressure pipeline connector 9. The two-stage lift solenoid control valve assembly 2, the first-stage lift solenoid control valve assembly 5, the suspension low-leakage assembly 6, and the multi-stage needle valve lift assembly 7 are installed sequentially from top to bottom inside the injector body locking nut 3 and the nozzle body 705 locking nut 8. The suspension low-leakage assembly 6 is located at the upper end of the methanol injector needle valve 701. The lower ends of the first-stage lift solenoid control valve assembly 5 and the two-stage lift solenoid control valve assembly 2 are respectively provided with methanol outlet throttling orifices. These orifices are connected to the suspension low-leakage assembly 6 and the multi-stage needle valve lift assembly 7 via internal injector pipelines. The high-pressure pipeline connector 9 is connected to the suspension low-leakage assembly 6 and the multi-stage needle valve lift assembly 7 via methanol inlet pipelines located on the side of the injector.

[0018] In embodiment 2, based on embodiment 1, the suspended low-leakage assembly 6 includes a suspended low-leakage valve reset spring 601, a suspended low-leakage valve 602, a low-leakage assembly body 603, a first control chamber 604, a first control chamber inlet control ring cavity 605, and a suspended throttling control orifice 606. The suspended low-leakage valve 602 and the suspended low-leakage valve reset spring 601 are installed inside the low-leakage assembly body 603. The suspended low-leakage valve reset spring 601 is positioned above the suspended low-leakage valve 602. The suspended low-leakage valve 602 and the low-leakage assembly body 603 cooperate to form the first control chamber inlet... The alcohol control ring cavity 605 is connected to the alcohol inlet pipeline on the side of the injector. Under the pre-tightening force of the suspension low leakage valve reset spring 601, the suspension low leakage valve 602 is located at the lower dead point, and the opening of the first control chamber alcohol inlet control ring cavity 605 is at its maximum. The suspension throttling control orifice 606 is set at the top of the suspension low leakage valve 602. The suspension low leakage valve 602 and the needle valve 701 cooperate to form the first control chamber 604. The suspension throttling control orifice 606 is connected to the alcohol outlet throttling orifice set at the lower end of the first-stage lift solenoid control valve assembly 5.

[0019] In embodiment 3, based on embodiment 1, the multi-stage needle valve lift assembly 7 includes a needle valve 701, a lift control valve block return spring 703, a lift control valve block 704, a nozzle body 705, a needle valve return spring 706, and an intermediate body 708. The intermediate body 708 contains a first inlet throttling orifice 709 and a second inlet throttling orifice 702. The lift control valve block 704 and the intermediate body 708 cooperate to form a second control chamber 707. The first inlet throttling orifice 709 communicates with the first control chamber 704 and the first control chamber inlet control ring cavity 605. The first control chamber 604 is located within the needle valve 701. At the top, the lift control valve block 704 is fitted onto the upper end of the needle valve 701. The second control chamber 707 is connected to the second alcohol inlet throttling orifice 702 and the alcohol outlet throttling orifice provided at the lower end of the second-stage lift solenoid control valve assembly 2. Under the action of the lift control valve block reset spring 703 and hydraulic pressure, the lift control valve block 704 sits on the nozzle body 705. Under the action of the needle valve reset spring 706 and hydraulic pressure, the needle valve 701 cooperates with the nozzle body 705 to form a sealing ring. In the non-working state, there is a gap between the lift control valve block 704 and the needle valve 701, which is the displacement distance of the needle valve 701 in the small lift injection mode.

[0020] In embodiment 4, based on embodiment 1, the diameter of the suspended throttling control orifice 606 is larger than the diameter of the first alcohol inlet throttling orifice 709, and the diameter of the suspended throttling control orifice 606 can have multiple options to adjust the opening size of the suspended low leakage valve 602 during the operation of the injector.

[0021] In implementation method 5, based on implementation method 1, when using the small-lift injection mode, current is supplied to the first-stage lift solenoid control valve assembly 5, while the second-stage lift solenoid control valve assembly 2 is de-energized. The first-stage lift solenoid control valve assembly 5 opens, causing the methanol outlet throttling orifice at its lower end to open. Methanol in the first control chamber 604 flows back to the low-pressure chamber through the suspended throttling control orifice 606 and the methanol outlet throttling orifice. Due to the throttling damping effect of the suspended throttling control orifice 606, the methanol liquid pressure in the first control chamber 604 is greater, that is, the methanol liquid pressure at the lower end of the suspended low-leakage valve 602 is greater than the methanol liquid pressure at the upper end. The upward liquid pressure at the lower end of the suspended low-leakage valve 602 overcomes the preload force of the suspended low-leakage valve reset spring 601, causing... As the suspended low-leakage valve 602 rises, the methanol inlet control ring 605 of the first control chamber closes, and the methanol flow rate into the first control chamber 604 from the first methanol inlet throttle orifice 709 gradually decreases. Because the first control chamber 604's liquid pressure continuously decreases due to the closure of the first control chamber 605, the pressure difference between the chambers before and after the suspended throttle control orifice 606 also gradually decreases. That is, the upward liquid pressure on the suspended low-leakage valve 602 gradually decreases. When its value is less than the preload of the suspended low-leakage valve reset spring 601, the suspended low-leakage valve 602 gradually falls back, and the first control chamber 605 gradually opens. Methanol in the injector side pipe flows through the first control chamber 605 and the first methanol inlet throttle orifice 709. The methanol flows back into the first control chamber 604 through the orifice 709, and the methanol pressure in the first control chamber 604 gradually increases. The pressure difference between the chambers before and after the suspension throttling control orifice 606 gradually increases until the upward hydraulic pressure on the suspension low-leakage valve 602 is balanced with the preload of the suspension low-leakage valve reset spring 601. At this point, the suspension low-leakage valve 602 will stabilize at a certain opening. Throughout the process, the suspension low-leakage valve 602 reduces the opening of the methanol inlet control ring chamber 605 in the first control chamber, thus reducing the methanol flow rate into the first control chamber 604 from the first methanol inlet throttling orifice 709. Consequently, the methanol flow rate out of the methanol outlet throttling orifice also decreases. The rapid depressurization of the first control chamber 604 causes the hydraulic pressure at the upper end of the injector needle valve 701 to drop rapidly. The lower pressure and greater reduction in amplitude significantly increase the upward acceleration of the needle valve, making it easier to achieve full opening and improving the stability of methanol injection. Due to the high hydraulic pressure in the second control chamber 707 and the preload of the return spring 703 of the lift control valve block, the needle valve 701 stops moving after rising to contact the lift control valve block 704, achieving highly stable methanol fuel injection in the small lift mode. The diameter of the suspended throttling control orifice 606 is larger than the diameter of the first methanol inlet throttling orifice 709. The opening size of the suspended low-leakage valve 602 depends on the selection of the diameter of the suspended throttling control orifice 606. By selecting different schemes for the diameter of the suspended throttling control orifice 606, the upward acceleration of the needle valve and the amount of methanol return can be flexibly adjusted.

[0022] In implementation method 6, based on implementation method 1, when using the large-lift injection mode, current is supplied to the secondary-stage lift solenoid control valve assembly 2, and both secondary-stage lift solenoid control valve assemblies 2 are opened. The methanol outlet throttle orifice at its lower end is opened, and methanol in the second control chamber 707 flows out through the methanol outlet throttle orifice. The fuel pressure in the second control chamber 707 decreases, and the downward hydraulic pressure on the lift control valve block 704 decreases. The lift control valve block 704 overcomes the preload force of the lift control valve block return spring 703 and moves upward until it reaches the maximum lift. The displacement space of the needle valve 701 is expanded. Current is supplied to the primary-stage lift solenoid control valve assembly 5, and the methanol outlet throttle orifice at the lower end of the primary-stage lift solenoid control valve assembly 5... When the throttle orifice opens, methanol in the first control chamber 604 flows back to the low-pressure chamber through the suspension throttle control orifice 606 and the methanol outlet throttle orifice. When the pressure in the first control chamber 604 is rapidly released, the hydraulic pressure at the upper end of the needle valve 701 drops rapidly. The needle valve 701 overcomes the preload force of the needle valve return spring 706 and lifts upward until it reaches its maximum lift. The increase in the needle valve lift increases the fuel flow area between the lower end of the needle valve 701 and the nozzle body 705, realizing methanol fuel injection in the high-lift mode. After the first-stage lift solenoid control valve assembly 5 is energized and opened, the suspension low-leakage assembly 6 also participates in the work. Its principle is similar to that described above and will not be repeated. It can also ensure a lower amount of methanol return and a higher needle valve acceleration, thereby improving the stability of methanol injection.

[0023] In implementation method 7, based on implementation method 1, when using the shoe-type injection mode, the first-stage lift solenoid control valve assembly 5 is first energized. Methanol in the first control chamber 604 flows back to the low-pressure chamber through the suspension throttling control orifice 606 and the methanol outlet throttling orifice. Under the action of the suspension low-leakage assembly 6, the methanol pressure in the first control chamber 604 drops rapidly. The needle valve 701 overcomes the spring preload and lifts up quickly, realizing a small amount of methanol injection with the needle valve 701 opening at a small lift. Then, the second-stage lift solenoid control valve assembly 2 is energized, and the methanol outlet throttling orifice at its lower end opens. Methanol in the second control chamber 707 flows out through the methanol outlet throttling orifice, and the methanol pressure in the second control chamber 707 drops. The needle valve 701 and the lift control valve block 704 together overcome the preload of the lift control valve block reset spring 703 and lift up until the maximum lift is reached. The fuel flow area between the lower end of the needle valve 701 and the nozzle body 705 is increased, and the methanol injection rate increases, realizing a highly stable shoe-type injection process for methanol fuel.

[0024] This invention enables rapid depressurization within the injector control chamber during operation via the suspended low-leakage component 6, significantly improving the injector needle valve acceleration, reducing the inconsistency between the needle valve opening moment and the upward motion phase, and enhancing methanol injection stability. Simultaneously, the suspended low-leakage component 6 also reduces methanol leakage during injection, achieving low-leakage and highly stable methanol injection. Furthermore, through the cooperation of the first-stage lift solenoid control valve component 5, the second-stage lift solenoid control valve component 2, the multi-stage needle valve lift component 7, and the suspended low-leakage component 6, flexible adjustment of small needle valve lift injection mode, large needle valve lift injection mode, and shoe-type injection mode can be achieved, meeting the engine's different requirements for the methanol injection rate curve. The suspended low-leakage component 6 participates in operation under all injection modes, thus achieving high methanol injection stability in each.

Claims

1. A highly stable methanol injector based on a suspended low-leakage component, characterized in that: The system comprises, from top to bottom, a first-stage lift-up solenoid control valve body, a second-stage lift-up solenoid control valve body, a low-leakage valve assembly body, an intermediate body, and a nozzle body. The first-stage lift-up solenoid control valve body houses the first-stage lift-up solenoid control valve assembly, which has a first-stage alcohol outlet throttling orifice at its bottom. The second-stage lift-up solenoid control valve body houses the second-stage lift-up solenoid control valve assembly, which also has a second-stage alcohol outlet throttling orifice at its bottom. The low-leakage valve assembly body houses a suspended low-leakage component. The intermediate body and nozzle body house a multi-stage needle valve lift-up assembly, which includes a needle valve. An alcohol storage chamber is formed between the needle valve and the nozzle body. A high-pressure pipeline connector is installed on the side of the second-stage lift-up solenoid control valve body. An alcohol inlet pipeline is installed in the high-pressure pipeline connector, passing through the second-stage lift-up solenoid control valve body, the first-stage lift-up solenoid control valve body, the low-leakage valve assembly body, the intermediate body, and the nozzle body, and connecting to the alcohol storage chamber.

2. A highly stable methanol injector based on a suspended low-leakage component according to claim 1, characterized in that: The suspended low-leakage assembly includes a suspended low-leakage valve, a suspended low-leakage valve reset spring installed above the suspended low-leakage valve, a suspended throttling control orifice opened at the top of the suspended low-leakage valve, a first control chamber opened inside the suspended low-leakage valve, the suspended throttling control orifice connecting the first control chamber and the first-stage alcohol outlet throttling orifice respectively, a first control chamber alcohol inlet control ring cavity is formed between the suspended low-leakage valve and the low-leakage valve assembly body, the first control chamber alcohol inlet control ring cavity is connected to the alcohol inlet pipeline, under the action of the pre-tightening force of the suspended low-leakage valve reset spring, the suspended low-leakage valve is located at the lower dead point, and the opening of the first control chamber alcohol inlet control ring cavity is in the maximum state.

3. A highly stable methanol injector based on a suspended low-leakage component according to claim 1, characterized in that: The multi-stage needle valve lift assembly also includes a lift control valve block. The top of the needle valve and the intermediate body form a needle valve cavity. A first alcohol inlet throttling orifice and a second alcohol inlet throttling orifice are provided in the intermediate body. The needle valve cavity is connected to the first control chamber and the first alcohol inlet throttling orifice, respectively. The first alcohol inlet throttling orifice is also connected to the alcohol inlet control ring cavity of the first control chamber. The needle valve is provided with a needle valve protrusion. The lift control valve block is sleeved on the outside of the needle valve. A needle valve return spring is sleeved on the needle valve. The needle valve return spring is located between the needle valve protrusion and the intermediate body above it. The lift control valve block is sleeved on the outside of the needle valve. The lift control valve block return spring is located between the lift control valve block and the intermediate body above it. The lift control valve block and the intermediate body form a second control chamber, which is connected to the second alcohol inlet throttling orifice and the second alcohol outlet throttling orifice respectively. Under the action of the lift control valve block return spring and hydraulic pressure, the lift control valve block sits on the nozzle body. Under the action of the needle valve return spring and hydraulic pressure, the needle valve cooperates with the nozzle body to form a sealing ring. In the non-working state, there is a gap between the lift control valve block and the needle valve.

4. A highly stable methanol injector based on a suspended low-leakage component according to claim 1, characterized in that: The diameter of the orifice in the suspension throttling control is larger than the diameter of the first alcohol inlet throttling orifice.

5. A highly stable methanol injector based on a suspended low-leakage component according to claim 1, characterized in that: In the short-lift injection mode, current is supplied to the first-stage lift solenoid control valve assembly, while the second-stage lift solenoid control valve assembly is de-energized. The first-stage methanol outlet throttling orifice opens, and methanol flows out of the first control chamber through the suspension throttling control orifice. The hydraulic pressure at the lower end of the suspension low-leakage valve overcomes the preload of the suspension low-leakage valve reset spring, causing the suspension low-leakage valve to lift upward. The methanol inlet control ring of the first control chamber closes, reducing the methanol flow rate into the first control chamber from the first methanol inlet throttling orifice. The hydraulic pressure at the lower end of the suspension low-leakage valve decreases. When it falls below the preload of the suspension low-leakage valve reset spring, the suspension low-leakage valve falls back until the hydraulic pressure on the suspension low-leakage valve balances the spring preload. The suspension low-leakage valve stabilizes at a fixed opening degree and stops moving when the needle valve rises to contact the lift control valve block.

6. A highly stable methanol injector based on a suspended low-leakage component according to claim 1, characterized in that: In the high-lift injection mode, current is applied to the secondary lift solenoid control valve assembly, the secondary methanol outlet throttle orifice opens, and methanol flows out of the second control chamber through the methanol outlet throttle orifice. The fuel pressure in the second control chamber decreases, and the lift control valve block rises against the preload of the lift control valve block return spring until it reaches the maximum lift. Current is applied to the primary lift solenoid control valve assembly, the primary methanol outlet throttle orifice opens, and the pressure in the primary control chamber is released, causing the hydraulic pressure at the upper end of the needle valve to decrease. The needle valve then rises against the preload of the needle valve return spring until it reaches the maximum lift.

7. A highly stable methanol injector based on a suspended low-leakage component according to claim 1, characterized in that: In boot-type injection mode, current is first applied to the first-stage lift solenoid control valve assembly. Under the action of the suspended low-leakage component, the methanol pressure in the first control chamber decreases, and the needle valve overcomes the spring preload and lifts upward, realizing a small amount of methanol injection with the needle valve opening at a small lift. Then, current is applied to the second-stage lift solenoid control valve assembly, and the methanol pressure in the second control chamber decreases. The needle valve and the lift control valve block together overcome the preload of the lift control valve block reset spring and lift upward until the maximum lift is reached.

Images