Hydrogen fuel injector and injection system

Abstract

The invention discloses a hydrogen fuel injector and an injection system, and relates to the technical field of fuel injectors for internal combustion engines, the hydrogen fuel injector comprises an injection part, a hydrogen inlet part, an electromagnetic control part and an oil inlet part which are sequentially arranged from bottom to top, and a first pressure storage cavity and a second pressure storage cavity are formed in the injection part; a cavity is formed in the electromagnetic control part, and an oil drainage channel communicating with the cavity is formed in the oil inlet part; and the electromagnetic control part is used for changing the hydraulic pressure in the first pressure storage cavity. Whether the spraying part sprays hydrogen or not can be accurately controlled through power-on and power-off of the electromagnetic valve control part, and the spraying duration of the hydrogen can be accurately controlled. The injection system comprises the hydrogen fuel injector and further comprises an oil inlet assembly communicated with the oil inlet part and an air inlet assembly communicated with the hydrogen inlet part. Through the arrangement of the oil inlet assembly and the gas inlet assembly, high-pressure oil and high-pressure hydrogen can be continuously and stably provided for the hydrogen fuel injector, and the use stability of the hydrogen fuel injector is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel injectors for internal combustion engines, and in particular to a hydrogen fuel injector and an injection system. Background Art

[0002] In response to the many problems of global climate anomalies, environmental quality decline and energy shortage, "low carbon" or "decarbonization" is the main direction of energy utilization in the world. Hydrogen is a new energy source that has received great attention. It has the advantages of fast combustion speed, high thermal efficiency, clean and pollution-free. It is widely used in the automotive industry, heavy machinery, shipping and other fields. The application of hydrogen fuel injection technology has broad prospects. The product of complete combustion of hydrogen is H2O, and no soot, hydrocarbons, CO and other products are generated. Compared with traditional internal combustion engines, hydrogen internal combustion engines have significant advantages of zero carbon emissions, high efficiency, high reliability and low cost.

[0003] At present, hydrogen internal combustion engines can be divided into two types according to the hydrogen supply method: premixed (PFI) and direct injection (DI). Hydrogen internal combustion engines that use premixed hydrogen supply are prone to abnormal combustion phenomena such as pre-ignition and flashback during the combustion process, which directly affects the power, economy and nitrogen oxide emission characteristics of hydrogen fuel internal combustion engines. Direct injection hydrogen internal combustion engines can effectively solve the problems of pre-ignition and flashback, and significantly improve power density. They are the development hotspot of hydrogen internal combustion engines in the recent stage, and have attracted great attention from domestic and foreign automobile companies and research institutions.

[0004] As a key component of a hydrogen internal combustion engine, the cycle injection duration and injection control accuracy of the hydrogen injector directly affect the performance of the engine; at the same time, hydrogen, as a gas medium, also has wear problems on the moving parts in the injector. Summary of the invention

[0005] The object of the present invention is to provide a hydrogen fuel injector which has good injection control accuracy and can accurately control the injection duration of hydrogen.

[0006] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a hydrogen fuel injector, comprising an injection part, a hydrogen intake part, an electromagnetic control part and an oil intake part which are arranged in sequence from bottom to top, a first oil passage connected to the oil tank is arranged in the oil intake part, a needle valve is arranged in the injection part, a first pressure accumulation chamber connected to the first oil passage and arranged on the upper side of the needle valve and a second pressure accumulation chamber connected to the hydrogen intake part and arranged on the lower side of the needle valve are arranged in the injection part, a cavity connected to the first pressure accumulation chamber is arranged in the electromagnetic control part, and an oil drain passage connected to the cavity is arranged in the oil intake part; the electromagnetic control part is used to change the size of the hydraulic pressure in the first pressure accumulation chamber.

[0007] The technical principle of the present invention is as follows: the first pressure storage chamber is filled with oil through the oil inlet and the first oil passage, and the cavity is also filled with oil to form hydraulic pressure. The second pressure storage chamber is filled with hydrogen through the hydrogen inlet to form air pressure. At this time, the hydraulic pressure is greater than the air pressure. Under the action of the hydraulic pressure, the needle valve seals the injection part to prevent hydrogen from spraying out. When the solenoid valve control part is energized, the oil drain channel can be opened, and the oil in the cavity flows out through the oil drain channel. The hydraulic pressure in the cavity is rapidly reduced, and the hydraulic pressure in the first pressure storage chamber connected to the cavity is also synchronously reduced. The air pressure in the second pressure storage chamber remains unchanged. At this time, the air pressure is greater than the hydraulic pressure. The air pressure overcomes the hydraulic pressure at the top of the needle valve to quickly lift the needle valve, and the injection part sprays hydrogen.

[0008] When the solenoid valve control unit is powered off, the cavity will be filled with oil again. At this time, the hydraulic pressure is greater than the air pressure, and the needle valve is controlled to seal the injection unit to complete the hydrogen injection.

[0009] Furthermore, the electromagnetic control part includes a solenoid valve, an air control valve, an armature shaft, an armature disk and a first return spring. The hydrogen intake part, the solenoid valve, the air control valve and the oil inlet part are arranged in sequence from bottom to top. A mounting groove is opened in the solenoid valve, and the first return spring is arranged in the mounting groove. The cavity is arranged on the surface of the air control valve away from the solenoid valve. An active cavity connected to both the mounting groove and the cavity is opened in the air control valve. The armature disk and the armature shaft are both arranged in the active cavity. The lower end of the armature shaft abuts against the first return spring, and the upper end face of the armature shaft abuts against the end face of the oil drain channel. A through hole connecting the cavity and the mounting groove is opened in the armature shaft. The armature disk is coaxially sleeved on the armature shaft, and a first gap is left between the armature disk and the upper end face of the solenoid valve. A wiring harness connector electrically connected to the solenoid valve is arranged on the oil inlet.

[0010] Furthermore, a control flow channel is provided in the air control valve, the lower end of the first oil channel is connected to the control flow channel, and an oil inlet metering channel is provided between the first oil channel and the control flow channel, the upper end of the control flow channel is connected to the cavity, and an oil outlet metering channel is provided between the control flow channel and the cavity.

[0011] Furthermore, the injection part includes a needle valve body and an intermediate body, the intermediate body is arranged at the lower side of the hydrogen intake part, the needle valve body is arranged at the lower side of the intermediate body, the needle valve is arranged in the needle valve body, the first pressure storage chamber is opened in the intermediate body, the second pressure storage chamber is opened in the needle valve body, a second return spring with a lower end abutting against an upper end of the needle valve is arranged in the first pressure storage chamber, the lower side of the needle valve is arranged in the second pressure storage chamber, an injection hole is opened at the lower end of the needle valve body, and when the solenoid valve is not energized, the needle valve and the needle valve body are in a line sealing state on the cone surface.

[0012] Furthermore, an adjustment pad is provided between the second return spring and the needle valve.

[0013] Furthermore, the hydrogen inlet part includes an inlet member and a receiving member, the inlet member is provided with a receiving groove for accommodating the receiving member, the solenoid valve is arranged on the receiving member, and the upper side of the inlet member is sleeved outside the solenoid valve, and the lower side of the inlet member is arranged on the intermediate body;

[0014] A first hydrogen channel is arranged in the air inlet, a second hydrogen channel connected with the first hydrogen channel is arranged in the intermediate body, and the second hydrogen channel is connected with the second pressure storage chamber, and the second hydrogen channel is a stepped cylinder with a wide top and a narrow bottom.

[0015] Furthermore, the electromagnetic control part also includes a solenoid valve nut which is coaxially sleeved outside the solenoid valve and the air control valve and has a second gap between the solenoid valve and the air control valve, the movable cavity is connected with the second gap, an injector nut which is coaxially sleeved outside the intermediate body and has a third gap between the intermediate body and the intermediate body, and the upper side of the injector nut is sleeved on the lower side of the hydrogen inlet part, the second gap is connected with the third gap, an oil return hole connected with the third gap is opened on the side wall of the injector nut, and an oil return channel connecting the receiving groove and the third gap is opened in the air intake part.

[0016] Furthermore, a protrusion is provided on the upper side of the intermediate body, the second hydrogen channel penetrates the protrusion, and the end surface of the second hydrogen channel and the surface of the protrusion are located on the same horizontal plane, and a sealing groove coaxially arranged with the second hydrogen channel is opened on the protrusion.

[0017] Furthermore, a second oil channel connected to the oil tank is provided in the oil inlet part, a lubrication ring groove connected to the second oil channel is opened in the injection part, the lubrication ring groove is connected to the side wall of the needle valve, a third oil channel connected to the lubrication ring groove at the lower side is opened in the intermediate body, the upper side of the third oil channel passes through the protrusion, and the upper end surface of the third oil channel and the surface of the protrusion are located in the same horizontal plane, and the third oil channel is connected to the sealing groove.

[0018] Another object of the present invention is to provide an injection system that can stably supply high-pressure oil and high-pressure hydrogen to a hydrogen fuel injector.

[0019] To achieve the above objectives, the present invention adopts the following technical solution: an injection system, comprising the hydrogen fuel injector as described above, and also comprising an oil inlet assembly connected to the oil inlet part and an air inlet assembly connected to the hydrogen air inlet part.

[0020] Furthermore, the oil inlet assembly includes a high-pressure oil pump connected to the oil tank and an oil transfer pump arranged between the high-pressure oil pump and the oil tank. A first high-pressure common rail pipe is arranged between the high-pressure oil pump and the oil inlet part, and the oil drain channel and the oil return hole are both connected to the oil tank.

[0021] Furthermore, the air intake assembly includes a pressure reducing valve communicated with the air storage tank and a second high-pressure common rail pipe arranged between the pressure reducing valve and the hydrogen intake portion.

[0022] The beneficial effects of the present invention are:

[0023] 1. Whether the injection part injects hydrogen can be accurately controlled by turning on and off the solenoid valve control part, and the injection duration of hydrogen can be controlled;

[0024] 2. Through the setting of the lubrication ring groove, the oil can adhere to the surface of the needle valve, thereby reducing the wear between the needle valve and the needle valve body. At the same time, the oil can seal the hydrogen in the hydrogen pressure storage chamber to prevent the hydrogen from rushing up to the chamber filled with oil;

[0025] 3. The second hydrogen channel can increase the intake rate, reduce the pressure fluctuation during hydrogen injection, and improve the injection stability;

[0026] 4. Through the setting of the oil inlet assembly and the air inlet assembly, high-pressure oil and high-pressure hydrogen can be continuously and stably provided to the hydrogen fuel injector, ensuring the stability of the use of the hydrogen fuel injector. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the structure of the invention;

[0028] Figure 2 is a cross-sectional view of the present invention;

[0029] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0030] Figure 4 for Figure 2 Enlarged view of point B in the middle;

[0031] Figure 5 It is a perspective view of the oil inlet;

[0032] Figure 6 is a perspective view of the air control valve;

[0033] Figure 7 is a perspective view of the air intake member;

[0034] Figure 8 A perspective view of the middleware;

[0035] Fig. 9 A top view of the middleware

[0036] Fig.10 is a perspective view of a needle valve body;

[0037] Fig.11 Schematic diagram of the injection system.

[0038] In the above drawings:

[0039] 1. Oil inlet; 101. First oil passage; 102. Second oil passage; 103. Oil drain passage;

[0040] 2. Electromagnetic control unit; 201. Electromagnetic valve; 2011. Mounting groove; 202. Air control valve; 2021. Active cavity; 2022. Control flow channel; 2023. Oil inlet metering channel; 2024. Oil outlet metering channel; 2025. Cavity; 203. Armature shaft; 2031. Through hole; 204. Armature plate; 205. First return spring; 206. First gap; 207. Solenoid valve nut; 208. Second gap;

[0041] 3. Hydrogen inlet; 301. Inlet member; 3011. First hydrogen channel; 3012. Receiving groove; 302. Receiving member; 303. Oil return channel;

[0042] 4. Injection unit; 401. Needle valve; 402. Intermediate body; 4021. First pressure storage chamber; 403. Needle valve body; 4031. Second pressure storage chamber; 404. Second hydrogen passage; 405. Second return spring; 406. Adjustment pad; 407. Injector nut; 408. Third gap; 409. Oil return hole; 410. Protrusion; 4101. Sealing groove; 411. Lubricating ring groove; 412. Third oil passage;

[0043] 5. Wiring harness connector; 6. Engine oil tank; 7. High-pressure oil pump; 8. Oil transfer pump; 9. Gas tank; 10. Pressure reducing valve; 11. First high-pressure common rail pipe; 12. Second high-pressure common rail pipe. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; the structures described in various embodiments can be freely combined without any conflict in structure or principle.

[0045] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0047] Some embodiments of the present invention are described below in conjunction with the accompanying drawings:

[0048] like Figure 1-Figure 10 As shown, the present invention proposes a hydrogen fuel injector, comprising an injection part 4, a hydrogen intake part 3, an electromagnetic control part 2 and an oil inlet part 1 which are arranged in sequence from bottom to top, a first oil passage 101 connected to the oil tank is arranged in the oil inlet part 1, a needle valve 401 is arranged in the injection part 4, a first pressure accumulation chamber 4021 which is connected to the first oil passage 101 and arranged on the upper side of the needle valve 401 and a second pressure accumulation chamber 4031 which is connected to the hydrogen intake part 3 and arranged on the lower side of the needle valve 401 are arranged in the injection part 4, a cavity 2025 which is connected to the first pressure accumulation chamber 4021 is arranged in the electromagnetic control part 2, and an oil drain passage 103 which is connected to the cavity 2025 is arranged in the oil inlet part 1; the electromagnetic control part 2 is used to change the size of the hydraulic pressure in the first pressure accumulation chamber 4021.

[0049] like Figure 2 As shown, through the oil inlet 1 and the first oil passage 101, the first pressure accumulator chamber 4021 is filled with oil, and the cavity 2025 is also filled with oil to form hydraulic pressure. The cavity 2025 can be in various forms, and preferably in an annular groove shape here, which is convenient for the flow of oil in the cavity 2025. The second pressure accumulator chamber 4031 is filled with hydrogen through the hydrogen inlet 3 to form air pressure. At this time, the hydraulic pressure is greater than the air pressure. Under the action of the hydraulic pressure, the needle valve 401 seals the injection part 4 to prevent hydrogen from spraying out. When the control part of the solenoid valve 201 is powered on, the oil drain channel 103 can be opened, and the oil in the cavity 2025 flows out through the oil drain channel 103. The hydraulic pressure in the cavity 2025 is rapidly reduced, and the hydraulic pressure in the first pressure accumulator chamber 4021 connected to the cavity 2025 is also reduced synchronously. The air pressure in the second pressure accumulator chamber 4031 remains unchanged. At this time, the air pressure is greater than the hydraulic pressure, and the needle valve 401 is quickly lifted, and the injection part 4 sprays hydrogen.

[0050] When the electromagnetic valve 201 control unit is powered off, the cavity 2025 will be filled with oil again. At this time, the hydraulic pressure is greater than the air pressure, and the needle valve 401 is controlled to seal the injection unit 4 to complete the hydrogen injection. The oil here can be engine oil, diesel or other lubricating oil, etc., preferably engine oil.

[0051] When the pressure of the hydrogen source remains constant, the injection duration of the hydrogen can be controlled by the solenoid valve 201, so that the injection amount of the hydrogen can be accurately controlled.

[0052] Furthermore, if Figure 2 and Figure 3 As shown, the electromagnetic control part 2 includes an electromagnetic valve 201, an air control valve 202, an armature shaft 203, an armature plate 204 and a first return spring 205. The hydrogen inlet part 3, the electromagnetic valve 201, the air control valve 202 and the oil inlet part 1 are arranged in sequence from bottom to top. The electromagnetic valve 201 is provided with a mounting groove 2011, the first return spring 205 is arranged in the mounting groove 2011, the cavity 2025 is arranged on the surface of the air control valve 202 away from the electromagnetic valve 201, and the air control valve 202 is provided with an active cavity connected to both the mounting groove 2011 and the cavity 2025. 2021, the armature plate 204 and the armature shaft 203 are both arranged in the active cavity 2021, the lower end of the armature shaft 203 is against the first return spring 205, the upper end surface of the armature shaft 203 is against the end surface of the oil leakage channel 103, and a through hole 2031 connecting the cavity 2025 and the mounting groove 2011 is opened in the armature shaft 203, the armature plate 204 is coaxially sleeved on the armature shaft 203, and a first gap 206 is left between the armature plate 204 and the upper end surface of the solenoid valve 201, and a wiring harness connector 5 electrically connected to the solenoid valve 201 is provided on the oil inlet portion 1.

[0053] The upper end surface of the armature shaft 203 is in surface contact with the end surface of the oil leakage passage 103. When the solenoid valve 201 is not energized, the upper end surface of the armature shaft 203 abuts against the end surface of the oil leakage passage 103 to seal the oil leakage passage 103 and prevent the oil in the cavity 2025 from flowing into the oil leakage passage 103. The solenoid valve 201 is energized through the wiring harness connector 5. Under the action of the electromagnetic force, the armature plate 204 is attracted to move downward, so that the armature plate 204 and the solenoid valve 201 are against each other, and the armature shaft 203 and the armature plate 204 have an interference fit. The armature plate 204 will drive the armature shaft 203 to move downward synchronously, compressing the first return spring 205. At this time, the armature shaft 203 is separated from the oil drain channel 103, and the oil in the cavity 2025 will flow to the oil drain channel 103, and the pressure in the cavity 2025 will decrease. At the same time, the pressure in the first pressure storage chamber 4021 connected to the cavity 2025 will also decrease, that is, the injector will inject hydrogen.

[0054] At the same time, the engine oil can flow through the armature shaft 203 to the mounting groove 2011 to cool and lubricate the armature, thereby ensuring the working stability of the electromagnetic control unit 2.

[0055] Furthermore, if Figure 6As shown, a control flow channel 2022 whose lower end is connected to the first pressure accumulation chamber 4021 is provided in the control valve 202, the lower end of the first oil channel 101 is connected to the control flow channel 2022, and an oil inlet metering channel 2023 is provided between the first oil channel 101 and the control flow channel 2022, the upper end of the control flow channel 2022 is connected to the cavity 2025, and an oil outlet metering channel 2024 is provided between the control flow channel 2022 and the cavity 2025.

[0056] The flow ratio between the oil outlet metering hole 2024 and the oil inlet metering channel 2023 or the oil outlet metering channel is 1.44, the diameter of the oil inlet metering hole is 0.55mm, the flow requirement is 1840ml / min, the diameter of the oil outlet metering hole is 0.65, and the flow requirement is 2660ml / min.

[0057] Through the above arrangement, when the engine oil in the cavity 2025 flows to the oil drain channel 103, it can prevent the engine oil in the first oil channel 101 from quickly filling the cavity 2025 again, ensuring that the engine oil in the cavity 2025 flows away quickly and reduces the pressure in the cavity 2025.

[0058] Furthermore, if Figure 2 , Figure 8 , Fig. 9 and Fig.10 As shown, the injection portion 4 includes a needle valve body 403 and an intermediate body 402, the intermediate body 402 is arranged at the lower side of the hydrogen intake portion 3, the needle valve body 403 is arranged at the lower side of the intermediate body 402, the needle valve 401 is arranged in the needle valve body 403, the first pressure storage chamber 4021 is opened in the intermediate body 402, the second pressure storage chamber 4031 is opened in the needle valve body 403, the first pressure storage chamber 4021 is provided with a second return spring 405 whose lower end abuts against the upper end of the needle valve 401, the lower side of the needle valve 401 is arranged in the second pressure storage chamber 4031, the lower end of the needle valve body 403 is provided with an injection hole, and when the solenoid valve 201 is not energized, the needle valve 401 and the needle valve body 403 are in a line sealing state on the cone surface.

[0059] The needle valve 401 is thin at both ends and thick in the middle, and a certain transition shoulder is left at the contact position between the two ends and the middle. When the solenoid valve 201 is not energized, the oil pressure is slightly higher than the hydrogen pressure (higher than 1-2 bar). The oil in the first pressure storage chamber 4021 acts on the equivalent cross-section of the tail of the needle valve 401, and the preload force of the second return spring 405 jointly presses the needle valve 401 against the needle valve body 403. When the solenoid valve 201 is energized, the pressure in the first pressure storage chamber 4021 decreases, and the hydrogen pressure contacts the transition shoulder on the lower side of the needle valve 401. Under the action of the air pressure, the oil pressure at the top of the needle valve 401 and the preload force of the second return spring 405 are overcome to lift the needle valve 401 and compress the second return spring 405 to complete the hydrogen injection.

[0060] When the solenoid valve 201 is powered off, the engine oil quickly fills the cavity 2025 and the first pressure storage chamber 4021 connected thereto, the pressure in the cavity 2025 and the first pressure storage chamber 4021 increases, and the needle valve 401 quickly seats under the action of the engine oil pressure and the preload force of the second return spring 405, closing the injection channel.

[0061] Furthermore, if Figure 2 and Figure 4 As shown, an adjustment pad 406 is provided between the second return spring 405 and the needle valve 401 .

[0062] The second return spring 405 can be given a preload force by adjusting the gasket 406 to ensure that the needle valve 401 and the conical surface of the needle valve body 403 abut against each other when the solenoid valve 201 is not energized, forming a seal and preventing hydrogen leakage. At the same time, the needle valve 401 can also work under a relatively low working pressure in certain working conditions (such as idling working conditions). For example, the minimum opening pressure required for idling working conditions is 47 bar. When the pressure difference between the upper and lower ends of the needle valve 401 is greater than or equal to 47 bar, the preload force of the second return spring 405 of the needle valve 401 is overcome, and the needle valve 401 is lifted to spray hydrogen.

[0063] Furthermore, if Figure 2 and Figure 7 As shown, the hydrogen inlet part 3 includes an inlet member 301 and a receiving member 302. The inlet member 301 is provided with a receiving groove 3012 for accommodating the receiving member 302. The solenoid valve 201 is arranged on the receiving member 302, and the upper side of the inlet member 301 is sleeved outside the solenoid valve 201, and the lower side of the inlet member 301 is arranged on the intermediate body 402.

[0064] A first hydrogen channel 3011 is provided in the air inlet 301 , a second hydrogen channel 404 communicating with the first hydrogen channel 3011 is provided in the intermediate body 402 , and the second hydrogen channel 404 is communicated with the second pressure storage chamber 4031 , and the second hydrogen channel 404 is a stepped cylinder that is wide at the top and narrow at the bottom.

[0065] External hydrogen can be introduced into the second pressure storage chamber 4031 through the first hydrogen channel 3011 and the second hydrogen channel 404. The number of the first hydrogen channels 3011 can be 2, 4, 6, etc. To ensure the air intake efficiency and production convenience, 4 are preferred. The number of the second hydrogen channels 404 is the same as the number of the first hydrogen channels 3011.

[0066] Hydrogen has a relatively low density, and in order to meet the engine power requirements, the intake volume needs to be increased. Through simulation calculations, the second hydrogen passage 404 is designed as an intake passage structure that is larger at the top and smaller at the bottom, which can increase the intake rate and reduce the pressure fluctuation during hydrogen injection, thereby improving the injection stability.

[0067] Furthermore, if Figure 2As shown, the electromagnetic control part 2 also includes a solenoid valve nut 207 coaxially sleeved outside the solenoid valve 201 and the air control valve 202 and leaving a second gap 208 between the solenoid valve 201 and the air control valve 202, the movable cavity 2021 is connected with the second gap 208, and an injector nut 407 coaxially sleeved outside the intermediate body 402 and leaving a third gap 408 between the intermediate body 402, and the upper side of the injector nut 407 is sleeved on the lower side of the hydrogen intake part 3, the second gap 208 is connected with the third gap 408, and a return oil hole 409 connected with the third gap 408 is opened on the side wall of the injector nut 407, and an oil return channel 303 connecting the receiving groove 3012 and the third gap 408 is opened in the intake part 301.

[0068] The hydrogen intake part 3, the intermediate body 402 and the needle valve body 403 are screwed together through the threaded connection of the injector nut 407. The excess oil in the mounting groove 2011 can flow to the third gap 408 through the second gap 208, and then flow back to the oil tank through the oil return hole. At the same time, the oil leaked from the connection between the various components can also flow to the third gap 408 through the third gap 408 or the oil return channel 303 and thus flow back to the oil tank.

[0069] Furthermore, if Figure 2 , Figure 8 and Fig. 9 As shown, a protrusion 410 is provided on the upper side of the intermediate body 402 , the second hydrogen channel 404 passes through the protrusion 410 , and the end surface of the second hydrogen channel 404 and the surface of the protrusion 410 are located on the same horizontal plane, and a sealing groove 4101 coaxially arranged with the second hydrogen channel 404 is opened on the protrusion 410 .

[0070] The number of sealing grooves 4101 matches the number of second hydrogen channels 404. By providing the protrusions 410, a gap can be left between the intermediate body 402 and the air intake member 301, and the sealing grooves 4101 are filled with engine oil to seal the connection between the first hydrogen channel 3011 and the second hydrogen channel 404 to prevent hydrogen leakage.

[0071] Furthermore, if Figure 2 , Figure 5 and Figure 6 As shown, a second oil passage 102 connected to the oil tank is provided in the oil inlet portion 1, a lubrication ring groove 411 connected to the second oil passage 102 is opened in the injection portion 4, the lubrication ring groove 411 is connected to the side wall of the needle valve 401, a third oil passage 412 connected to the lubrication ring groove 411 at the lower side is opened in the intermediate body 402, the upper side of the third oil passage 412 passes through the protrusion 410, and the upper end surface of the third oil passage 412 and the surface of the protrusion 410 are located at the same horizontal plane, and the third oil passage 412 is connected to the sealing groove 4101.

[0072] By setting the lubricating ring groove 411, the engine oil can adhere to the surface of the needle valve 401, thereby reducing the wear between the needle valve 401 and the needle valve body 403, and the oil can seal the hydrogen in the hydrogen pressure storage chamber to prevent the hydrogen from rising. The engine oil in the lubricating ring groove 411 will flow to the sealing groove 4101 through the third oil channel 412 to seal the connection between the first hydrogen channel 3011 and the second hydrogen channel 404.

[0073] like Fig.11 As shown, an injection system includes the hydrogen fuel injector as described above, and also includes an oil inlet assembly connected to the oil inlet part 1 and an air inlet assembly connected to the hydrogen air inlet part 3.

[0074] The hydrogen fuel injector in this injection system is a high-pressure direct-injection injector. Through the setting of the oil inlet component and the air inlet component, it can continuously and stably provide high-pressure oil and high-pressure hydrogen to the hydrogen fuel injector, ensuring the stability of the use of the hydrogen fuel injector.

[0075] Furthermore, if Fig.11 As shown, the oil inlet assembly includes a high-pressure oil pump 7 connected to the oil tank and an oil delivery pump 8 arranged between the high-pressure oil pump 7 and the oil tank. A first high-pressure common rail pipe 11 is arranged between the high-pressure oil pump 7 and the oil inlet part 1, and the oil drain channel 103 and the oil return hole 409 are both connected to the oil tank.

[0076] The oil tank in the present invention is an oil tank isolated from the engine oil tank 6, and no additional oil tank is required, and the structure is compact. A coarse filter and a fine filter are arranged in the oil pump 8. The oil in the oil tank first passes through the coarse filter and then enters the oil pump 8. The oil passing through the oil pump 8 then passes through the fine filter and enters the high-pressure oil pump 7, which can prevent the impurities in the oil from affecting the hydrogen fuel injector. The high-pressure oil pump 7 pressurizes the oil, and then enters the first high-pressure common rail pipe 11 to stabilize the pressure, and finally enters the hydrogen fuel injector through the oil inlet 1, providing the hydrogen fuel injector with stable high-pressure oil. The oil in the hydrogen fuel injector can flow back to the oil tank again through the oil drain channel 103 and the oil return hole 409.

[0077] Furthermore, if Fig.11 As shown, the air intake assembly includes a pressure reducing valve 10 connected to the air storage tank 9 and a second high-pressure common rail pipe 12 arranged between the pressure reducing valve 10 and the hydrogen intake portion 3 .

[0078] At present, the most commonly used high-pressure gas storage cylinders for hydrogen are of two specifications: 350 bar and 700 bar. The rated working pressure set for the hydrogen fuel injector in the present invention is 300 bar, so the gas storage tank 9 with a pressure of 350 bar is selected to store hydrogen. At certain operating points (such as idling), a lower working pressure may be required. The pressure reducing valve 10 can reduce the hydrogen pressure in the gas storage tank 9 to the required working pressure. The depressurized hydrogen enters the second high-pressure common rail pipe 12 to stabilize the pressure, and finally enters the hydrogen fuel injector through the hydrogen intake part 3 to provide hydrogen with stable pressure for the hydrogen fuel injector. The pressure reducing valve is a prior art and will not be described in detail here.

Claims

1. A hydrogen fuel injector, characterized in that: The invention comprises an injection part (4), a hydrogen intake part (3), an electromagnetic control part (2) and an oil intake part (1) which are arranged in sequence from bottom to top; a first oil passage (101) which is connected to an oil tank is arranged in the oil intake part (1); a needle valve (401) is arranged in the injection part (4); a first pressure accumulating chamber (4021) which is connected to the first oil passage (101) and arranged on the upper side of the needle valve (401) and a second pressure accumulating chamber (4031) which is connected to the hydrogen intake part (3) and arranged on the lower side of the needle valve (401) are arranged in the injection part (4); a cavity (2025) which is connected to the first pressure accumulating chamber (4021) is arranged in the electromagnetic control part (2); and an oil drain passage (103) which is connected to the cavity (2025) is arranged in the oil intake part (1); the electromagnetic control part (2) is used to change the hydraulic pressure in the first pressure accumulating chamber (4021).

2. A hydrogen fuel injector according to claim 1, characterized in that: The electromagnetic control part (2) comprises an electromagnetic valve (201), an air control valve (202), an armature shaft (203), an armature plate (204) and a first return spring (205); the hydrogen inlet part (3), the electromagnetic valve (201), the air control valve (202) and the oil inlet part (1) are arranged in sequence from bottom to top; a mounting groove (2011) is provided in the electromagnetic valve (201); the first return spring (205) is arranged in the mounting groove (2011); a cavity (2025) is provided on a surface of the air control valve (202) away from the electromagnetic valve (201); and a movable cavity (2025) is provided in the air control valve (202) and is in communication with both the mounting groove (2011) and the cavity (2025). 2021), the armature plate (204) and the armature shaft (203) are both arranged in the movable cavity (2021), the lower end of the armature shaft (203) is against the first return spring (205), the upper end surface of the armature shaft (203) is against the end surface of the oil leakage channel (103), a through hole (2031) connecting the cavity (2025) and the mounting groove (2011) is opened in the armature shaft (203), the armature plate (204) is coaxially sleeved on the armature shaft (203), and a first gap (206) is left between the armature plate (204) and the upper end surface of the electromagnetic valve (201), and a wiring harness connector (5) electrically connected to the electromagnetic valve (201) is arranged on the oil inlet portion (1).

3. A hydrogen fuel injector according to claim 2, characterized in that: A control flow channel (2022) whose lower end is connected to the first pressure accumulation chamber (4021) is provided in the air control valve (202); the lower end of the first oil channel (101) is connected to the control flow channel (2022), and an oil inlet metering channel (2023) is provided between the first oil channel (101) and the control flow channel (2022); the upper end of the control flow channel (2022) is connected to the cavity (2025), and an oil outlet metering channel (2024) is provided between the control flow channel (2022) and the cavity (2025).

4. A hydrogen fuel injector according to any one of claims 1 to 3, characterized in that: The injection portion (4) comprises a needle valve body (403) and an intermediate body (402), wherein the intermediate body (402) is arranged at the lower side of the hydrogen inlet portion (3), the needle valve body (403) is arranged at the lower side of the intermediate body (402), the needle valve (401) is arranged in the needle valve body (403), a first pressure storage chamber (4021) is opened in the intermediate body (402), a second pressure storage chamber (4031) is opened in the needle valve body (403), a second return spring (405) whose lower end abuts against the upper end of the needle valve (401) is arranged in the first pressure storage chamber (4021), the lower side of the needle valve (401) is arranged in the second pressure storage chamber (4031), an injection hole is opened at the lower end of the needle valve body (403), and when the solenoid valve (201) is not energized, the needle valve (401) and the needle valve body (403) are in a line sealing state on the conical surface.

5. A hydrogen fuel injector according to claim 4, characterized in that: An adjustment pad (406) is provided between the second return spring (405) and the needle valve (401).

6. A hydrogen fuel injector according to claim 4, characterized in that: The hydrogen gas inlet part (3) comprises an inlet member (301) and a receiving member (302); the inlet member (301) is provided with a receiving groove (3012) for accommodating the receiving member (302); the solenoid valve (201) is arranged on the receiving member (302); the upper side of the inlet member (301) is sleeved outside the solenoid valve (201); and the lower side of the inlet member (301) is arranged on the intermediate body (402); A first hydrogen channel (3011) is arranged in the air inlet (301), a second hydrogen channel (404) communicating with the first hydrogen channel (3011) is arranged in the intermediate body (402), and the second hydrogen channel (404) is communicated with the second pressure storage chamber (4031), and the second hydrogen channel (404) is a stepped cylinder that is wide at the top and narrow at the bottom.

7. A hydrogen fuel injector according to claim 5, characterized in that: The hydrogen gas inlet part (3) comprises an inlet member (301) and a receiving member (302); the inlet member (301) is provided with a receiving groove (3012) for accommodating the receiving member (302); the solenoid valve (201) is arranged on the receiving member (302); the upper side of the inlet member (301) is sleeved outside the solenoid valve (201); and the lower side of the inlet member (301) is arranged on the intermediate body (402); A first hydrogen channel (3011) is arranged in the air inlet (301), a second hydrogen channel (404) communicating with the first hydrogen channel (3011) is arranged in the intermediate body (402), and the second hydrogen channel (404) is communicated with the second pressure storage chamber (4031), and the second hydrogen channel (404) is a stepped cylinder that is wide at the top and narrow at the bottom.

8. A hydrogen fuel injector according to claim 6 or 7, characterized in that: The electromagnetic control part (2) further comprises an electromagnetic valve nut (207) coaxially sleeved outside the electromagnetic valve (201) and the air control valve (202) and leaving a second gap (208) between the electromagnetic valve (201) and the air control valve (202); the movable cavity (2021) is connected to the second gap (208); an ejector nut (407) coaxially sleeved outside the intermediate body (402) and leaving a third gap (408) between the intermediate body (402); the upper side of the ejector nut (407) is sleeved on the lower side of the hydrogen intake part (3); the second gap (208) is connected to the third gap (408); an oil return hole (409) connected to the third gap (408) is formed on the side wall of the ejector nut (407); and an oil return channel (303) connected to the receiving groove (3012) and the third gap (408) is formed in the intake member (301).

9. A hydrogen fuel injector according to claim 6 or 7, characterized in that: A protrusion (410) is provided on the upper side of the intermediate body (402), the second hydrogen channel (404) passes through the protrusion (410), and the end surface of the second hydrogen channel (404) and the surface of the protrusion (410) are located on the same horizontal plane, and a sealing groove (4101) coaxially arranged with the second hydrogen channel (404) is opened on the protrusion (410).

10. A hydrogen fuel injector according to claim 9, characterized in that: The oil inlet portion (1) is provided with a second oil passage (102) connected to the oil tank, the injection portion (4) is provided with a lubrication ring groove (411) connected to the second oil passage (102), the lubrication ring groove (411) is connected to the side wall of the needle valve (401), the intermediate body (402) is provided with a third oil passage (412) connected to the lubrication ring groove (411) at the bottom, the upper side of the third oil passage (412) passes through the protrusion (410), and the upper end surface of the third oil passage (412) and the surface of the protrusion (410) are located at the same horizontal plane, and the third oil passage (412) is connected to the sealing groove (4101).

11. An injection system, characterized in that: A hydrogen fuel injector according to any one of claims 1 to 10, further comprising an oil inlet assembly communicating with the oil inlet portion (1) and an air inlet assembly communicating with the hydrogen inlet portion (3).

12. An injection system according to claim 11, characterized in that: The oil inlet assembly comprises a high-pressure oil pump (7) connected to the oil tank and an oil delivery pump (8) arranged between the high-pressure oil pump (7) and the oil tank, a first high-pressure common rail pipe (11) is arranged between the high-pressure oil pump (7) and the oil inlet part (1), and the oil drain channel (103) and the oil return hole (409) are both connected to the oil tank.

13. An injection system according to claim 11, characterized in that: The air intake assembly comprises a pressure reducing valve (10) connected to a gas storage tank (9) and a second high-pressure common rail pipe (12) arranged between the pressure reducing valve (10) and a hydrogen intake portion (3).

14. An injection system according to claim 12, characterized in that: The air intake assembly comprises a pressure reducing valve (10) connected to a gas storage tank (9) and a second high-pressure common rail pipe (12) arranged between the pressure reducing valve (10) and a hydrogen intake portion (3).

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