Multi-fuel electronically controlled injector with nested double needle valve and parallel single needle valve

Abstract

The application aims to provide a multi-fuel electric control injector with nested double needle valve and parallel single needle valve, belonging to the field of internal combustion engine. It comprises different fuel interfaces, pressure accumulation cavities, needle valves, control assemblies and the like. The diesel pressure accumulation cavity and other components are installed through specific connection mode, the methanol needle valve is nested in the injection hole, the double electromagnetic valve control assembly and the pilot control assembly work in coordination. The application accurately controls each needle valve through the double electromagnetic valve control assembly, realizes independent injection of diesel, methanol and ammonia fuel, and multi-fuel combined injection or pre-main injection through mode combination, solves the problems of difficult ignition of methanol and ammonia fuel and difficult control of multi-fuel injection, and can be applied to the field of internal combustion engine fuel injection, and improves fuel utilization efficiency and environmental protection performance of the engine.

Description

TECHNICAL FIELD

[0001] The present application relates to an internal combustion engine, in particular, an oil injector of the internal combustion engine. BACKGROUND

[0002] With the increasingly stringent environmental requirements, the use of traditional fossil fuels is facing great challenges. Diesel, as a commonly used fuel for internal combustion engines, produces pollutants during combustion, which has a certain impact on the environment. Methanol and ammonia fuels have become potential alternative fuels due to their low emissions and renewable advantages. However, the physical and chemical properties of methanol and ammonia fuels are quite different from those of diesel, such as high latent heat of vaporization and high ignition temperature of methanol, slow combustion speed and difficult ignition of ammonia, etc., which makes their application in engines face many problems, such as difficulty in ignition and unstable combustion, etc. At the same time, it is also a technical difficulty to achieve precise injection and flexible control of multiple fuels. SUMMARY

[0003] The purpose of the present application is to provide a nested double needle valve and parallel single needle valve multi-fuel electric control injector that can solve the problems of methanol and ammonia fuel not being easy to ignite and difficult control of multi-fuel injection.

[0004] The purpose of the present application is achieved in that:

[0005] The nested double needle valve and parallel single needle valve multi-fuel electric control injector of the present application is characterized in that: it comprises a fastening cap and an upper fastening cap, the fastening cap is fixed outside the upper fastening cap, and the upper fastening cap is sequentially provided with a pressure accumulation cavity wall, an oil path adjustment fast, an electromagnetic valve control assembly fastening block, an upper quantity orifice plate, a middle quantity orifice plate, a lower quantity orifice plate and a nozzle from top to bottom. The electromagnetic valve control assembly fastening block is installed with a double electromagnetic valve control assembly. The middle quantity orifice plate, the lower quantity orifice plate and the nozzle are installed with a pilot control assembly. The fastening cap is respectively provided with a diesel interface, a methanol interface and an ammonia fuel interface. The pressure accumulation cavity wall is respectively provided with a diesel pressure accumulation cavity, a methanol pressure accumulation cavity and an ammonia fuel pressure accumulation cavity. The diesel pressure accumulation cavity is connected with the diesel interface, the methanol pressure accumulation cavity is connected with the methanol interface, and the ammonia fuel pressure accumulation cavity is connected with the ammonia fuel interface. The pilot control assembly comprises a diesel needle valve, a methanol needle valve and an ammonia fuel needle valve. The diesel needle valve is located inside the methanol needle valve. The methanol needle valve and the nozzle form a methanol needle valve oil storage cavity. The diesel needle valve and the methanol needle valve form a diesel needle valve oil storage cavity. The ammonia fuel needle valve and the nozzle form an ammonia fuel oil storage cavity. The methanol needle valve oil storage cavity is connected with the methanol pressure accumulation cavity through a methanol supply pipeline. The diesel needle valve oil storage cavity is connected with the diesel pressure accumulation cavity through a diesel supply pipeline. The ammonia fuel oil storage cavity is connected with the ammonia fuel pressure accumulation cavity through an ammonia fuel supply pipeline.

[0006] The present application can also include:

[0007] 1. The dual solenoid valve control assembly includes a housing, an upper solenoid valve, and a lower solenoid valve. The upper solenoid valve includes an upper solenoid valve armature, an upper section of a control valve core, and an upper solenoid valve return spring. The lower solenoid valve includes a lower solenoid valve armature, a lower section of a control valve core, and a lower solenoid valve return spring. The upper and lower sections of the control valve core are symmetrically installed inside the housing of the dual solenoid valve control assembly. The upper solenoid valve return spring is fitted onto the upper section of the control valve core, and the upper solenoid valve armature is installed on the top of the upper section of the control valve core. The lower section of the control valve core is fitted with a lower solenoid valve return spring, and the lower solenoid valve armature is installed at the bottom of the lower section of the control valve core. The housing of the dual solenoid valve control assembly is respectively provided with an upper chamber of the control valve core, a lower chamber of the control valve core, an upper oil return hole, and a lower oil return hole. The lower section of the control valve core is provided with an internal oil passage. The upper section of the control valve core and the housing of the dual solenoid valve control assembly form an upper oil return chamber, and the lower section of the control valve core and the housing of the dual solenoid valve control assembly form a lower oil return chamber. The upper oil return chamber is connected to the upper oil return hole, and the lower oil return chamber is connected to the lower oil return hole.

[0008] 2. The main body of the diesel needle valve is located inside the nozzle, with its top passing through the lower orifice plate and positioned within the middle orifice plate; the methanol needle valve is located inside the nozzle; the main body of the ammonia fuel needle valve is located inside the nozzle, with its top passing through the lower orifice plate and positioned within the middle orifice plate; a diesel needle valve return spring is fitted on the top of the diesel needle valve, forming the diesel needle valve control chamber; a methanol needle valve return spring is fitted on the top of the methanol needle valve, forming the methanol needle valve control chamber; the top of the ammonia fuel needle valve and the middle orifice plate form the ammonia fuel needle valve control chamber. The feed needle valve has a protrusion located inside the nozzle. An ammonia fuel needle valve return spring is fitted above the protrusion, with its upper end resting against the bottom of the intermediate orifice plate. The location of the return spring forms the ammonia fuel needle valve chamber. The upper orifice plate is equipped with a first servo oil supply circuit, a second servo oil supply circuit, and a third servo oil supply circuit. The first servo oil supply circuit connects to the methanol needle valve control chamber via an inlet throttle orifice. The second servo oil supply circuit connects to the diesel needle valve control chamber. The inlet throttle orifice connects to the diesel needle valve control chamber. The third servo oil supply circuit connects to the ammonia fuel needle valve control chamber via the inlet throttle orifice. The intermediate orifice plate contains throttle orifices for the diesel needle valve's reservoir and the ammonia fuel needle valve's reservoir. The lower orifice plate contains a throttle orifice for the methanol needle valve's reservoir. The diesel needle valve's reservoir outlet throttle orifice connects to the diesel needle valve control chamber and its return oil circuit. The return oil circuit of the diesel needle valve control chamber is coordinated with the internal oil circuit of the control valve core. The methanol needle valve control chamber outlet throttles... The orifices are respectively connected to the methanol needle valve control chamber and the methanol needle valve control chamber return oil line. The methanol control chamber return oil line is connected to the lower chamber of the control valve core. The ammonia fuel needle valve control chamber oil outlet throttling orifice is respectively connected to the ammonia fuel needle valve control chamber and the ammonia fuel needle valve control chamber return oil line. The ammonia fuel needle valve control chamber return oil line is connected to the upper chamber of the control valve core. The nozzle at the bottom of the methanol needle valve is equipped with a methanol needle valve spray orifice. The nozzle at the bottom of the diesel needle valve is equipped with a diesel needle valve spray orifice. The nozzle at the bottom of the ammonia fuel needle valve is equipped with an ammonia fuel needle valve spray orifice.

[0009] 3. In the initial state, in the dual solenoid valve control assembly, the coils of the upper solenoid valve and the lower solenoid valve are both de-energized. The upper and lower sections of the control valve core are placed in the middle position of the dual solenoid valve control assembly housing due to the action of the upper and lower solenoid valve return springs. The upper and lower chambers of the control valve core are sealed, and the return oil line of the diesel needle valve control chamber is not connected to the internal oil line of the control valve core.

[0010] In the pilot control assembly, the high-pressure servo oil in the diesel needle valve control chamber, methanol needle valve control chamber, and ammonia fuel needle valve control chamber provides downward pressure to the upper surface of the needle valve. This pressure, combined with the return springs of the ammonia fuel needle valve, methanol needle valve, and diesel needle valve, causes the diesel needle valve, methanol needle valve, and ammonia fuel needle valve to sit down, thus completing the sealing of the diesel injection port, methanol injection port, and ammonia fuel injection port.

[0011] 4. In methanol injection mode, the upper solenoid valve coil is energized and the lower solenoid valve coil is de-energized. The upper solenoid valve coil exerts an upward attraction on the armature of the upper solenoid valve, causing the upper section of the control valve core to move upward. The lower section of the control valve core moves upward due to the action of the lower solenoid valve return spring. During this process, the upward displacement limit of the upper section of the control valve core is limited by the flange on the top surface of the large end of the upper section of the control valve core housing of the dual solenoid valve control assembly. The seal formed by the top recess of the lower section of the control valve core and the bottom protrusion of the upper section of the control valve core is not released because the seal length is greater than the displacement of a single solenoid valve. The seal length of the lower chamber of the control valve core is less than the displacement, so the seal is released. The methanol needle valve control chamber is connected to the lower return oil chamber through the methanol needle valve control chamber return oil pipeline. Servo oil is discharged from the lower return oil hole. The hydraulic pressure in the methanol needle valve control chamber gradually reduces the downward pressure on the methanol needle valve. When the resultant force of this downward pressure and the methanol needle valve return spring is less than the upward force of the high-pressure methanol on the methanol needle valve, the methanol needle valve is lifted, and methanol is sprayed out from the methanol injection hole through the methanol needle valve pressure chamber, and injection begins.

[0012] When closed, the upper solenoid valve coil is de-energized, and its upward attraction on the upper solenoid valve armature disappears. The upper section of the control valve core is driven by the upper solenoid valve return spring to move the lower section of the control valve core downward. When it moves to the force balance point between the upper section of the control valve core and the lower solenoid valve return spring, the lower section of the control valve core stops at the initial position, the lower chamber of the control valve core is sealed, the oil discharge process of the methanol needle valve control chamber ends, and the servo oil re-pressurizes the methanol needle valve control chamber through the first servo oil inlet circuit and the methanol needle valve control chamber inlet throttle orifice. When the downward pressure generated by the servo oil and the methanol needle valve return spring is greater than the upward force of the high-pressure methanol on the methanol needle valve, the methanol needle valve sits down, and the oil injection process ends.

[0013] 5. During ammonia fuel injection mode, the upper solenoid valve coil is de-energized, and the lower solenoid valve coil is energized. The lower solenoid valve coil exerts a downward attraction on the lower solenoid valve return spring, causing the lower section of the control valve core to move downward. The upper section of the control valve core moves downward due to the action of the upper solenoid valve return spring. During this process, the downward displacement limit of the lower section of the control valve core is limited by the flange on the lower top surface of the large end of the lower section of the control valve core housing. The seal formed by the top recess of the lower section of the control valve core and the bottom protrusion of the upper section of the control valve core has a sealing length greater than that of a single solenoid valve. The solenoid valve is displaced but not released. The sealing length of the upper chamber of the control valve core is less than the displacement, the seal is released, the ammonia fuel needle valve control chamber is connected to the upper return oil chamber through the ammonia fuel needle valve control chamber return oil pipeline, the servo oil is discharged from the upper return oil hole, the hydraulic pressure in the ammonia fuel needle valve control chamber 3 gradually decreases the downward pressure on the ammonia fuel needle valve, when the resultant force of the downward pressure and the ammonia fuel needle valve reset spring is less than the upward force of the high pressure ammonia fuel on the ammonia fuel needle valve, the ammonia fuel needle valve is lifted, and the high pressure ammonia fuel is sprayed out from the ammonia fuel injection hole through the ammonia fuel needle valve pressure chamber, and the injection begins;

[0014] When closed, the lower solenoid valve coil is de-energized, and its downward attraction on the lower solenoid valve return spring disappears. The lower section of the control valve core is driven by the lower solenoid valve return spring to move the upper section of the control valve core upward. When it moves to the force balance point between the upper and lower solenoid valve return springs, the upper section of the control valve core stops at the initial position, the upper chamber of the control valve core is sealed, the oil discharge process of the ammonia fuel needle valve control chamber ends, and the servo oil re-pressurizes the ammonia fuel needle valve control chamber through the third servo oil inlet circuit and the ammonia fuel needle valve control chamber inlet throttle orifice. When the downward pressure generated by the servo oil and the ammonia fuel needle valve return spring is greater than the upward force of the high-pressure ammonia fuel on the ammonia fuel needle valve, the ammonia fuel needle valve sits down, and the fuel injection process ends.

[0015] 6. When in diesel fuel injection mode, the coils of the upper and lower solenoid valves are energized simultaneously. The resulting attraction causes the armature of the upper solenoid valve to move the upper section of the control valve core upward, and the armature of the lower solenoid valve to move the lower section of the control valve core downward. The total displacement of the two solenoid valves causes the seal formed by the concave top of the lower section of the control valve core and the protruding bottom part of the upper section of the control valve core to be released. The servo oil in the diesel needle valve control chamber reaches the lower return oil chamber through the return oil pipeline of the diesel needle valve control chamber and the oil circuit inside the control valve core, and then is discharged from the lower return oil hole. The hydraulic pressure in the diesel needle valve control chamber gradually reduces the downward pressure on the diesel needle valve. When the resultant force of this downward pressure and the return spring of the diesel needle valve is less than the upward force of the diesel fuel on the diesel needle valve, the diesel needle valve is lifted, and the diesel fuel is injected from the diesel injection hole through the diesel needle valve pressure chamber, and the injection begins.

[0016] When closed, both the lower and upper solenoid valves are de-energized. The upward attraction of the upper solenoid valve on its armature disappears, and the downward attraction of the lower solenoid valve on its armature disappears. The upper section of the control valve core moves downward under the action of the upper solenoid valve's return spring, and the lower section of the control valve core moves upward under the action of the lower solenoid valve's return spring. When they reach the force balance point of the upper and lower solenoid valve's return springs, the upper and lower sections of the control valve core stop at their initial positions. The seal between the top recess of the lower section of the control valve core and the bottom protrusion of the upper section of the control valve core is re-established, and the oil discharge process of the diesel needle valve control chamber terminates. Servo oil from the first servo oil inlet path passes through the diesel needle valve control chamber inlet throttle orifice to re-pressurize the diesel needle valve control chamber. When the downward pressure generated by the servo oil and the diesel needle valve return spring is greater than the upward force of the diesel fuel on the diesel needle valve, the diesel needle valve sits down, and the fuel injection process ends.

[0017] The advantages of this invention are as follows: This invention precisely controls each needle valve through a dual solenoid valve control component, realizing independent injection of diesel, methanol and ammonia fuels, as well as multi-fuel combined injection or pre-main injection through mode combination, solving the problems of difficult ignition of methanol and ammonia fuels and multi-fuel injection control, and can be applied to the field of internal combustion engine fuel injection, improving engine fuel utilization efficiency and environmental performance. Attached Figure Description

[0018] Fig. 1 This is a schematic diagram of the structure of the present invention;

[0019] Fig. 2 This is a schematic diagram of the dual solenoid valve control assembly.

[0020] Fig. 3 This is a schematic diagram of the pilot control component. Detailed Implementation

[0021] The invention will now be described in more detail with reference to the accompanying drawings:

[0022] Combination Figs. 1-3The multi-fuel electronically controlled fuel injector of the present invention, which consists of a nested double needle valve and a parallel single needle valve, comprises a diesel interface 1, a methanol interface 2, a methanol accumulator chamber 3, an outer wall of the accumulator chamber 4, an oil circuit regulating block 5, a diesel supply pipeline 6, a methanol supply pipeline 7, a tightening cap 8, a diesel needle valve control chamber return oil circuit 9, a first servo oil inlet oil circuit 10, a second servo oil inlet oil circuit 11, a pilot control component 12, a diesel needle valve 13, a methanol needle valve 14, a methanol needle valve oil holding chamber 15, a diesel needle valve oil holding chamber 16, a methanol needle valve nozzle 17, a methanol needle valve pressure chamber 18, and an ammonia... The system comprises a fuel inlet 19, a fastening cap 20, a diesel fuel accumulator chamber 21, an ammonia fuel accumulator chamber 22, a dual solenoid valve control assembly 23, a dual solenoid valve control assembly fastening block 24, an ammonia fuel supply line 25, an ammonia fuel needle valve control chamber return line 26, a methanol needle valve control chamber return line 27, an upper metering orifice plate 28, a third servo oil supply line 29, a nozzle 30, an ammonia fuel needle valve oil holding chamber 31, an ammonia fuel needle valve 32, an ammonia fuel needle valve pressure chamber 33, an ammonia fuel needle valve nozzle 34, a diesel fuel needle valve pressure chamber 35, and a diesel fuel needle valve nozzle 36.

[0023] The fastening cap 20, the outer wall of the accumulator chamber 4, the oil circuit adjusting block 5, the upper measuring orifice plate 28, the pilot control assembly 12, and the nozzle 30 are installed from top to bottom via positioning pins, and are entirely encased in the return oil circuit 8 of the diesel needle valve control chamber. The upper part is threaded to the fastening cap 20, and the lower part is connected to the nozzle 30 via a bayonet. The dual solenoid valve control assembly 23 is encased in the dual solenoid valve control assembly fastening block 24, forming a single unit. The methanol needle valve 13 is nested within the methanol needle valve 14 and placed together with the ammonia fuel 32 in the pre-reserved gap in the nozzle 30. The bottom of the nozzle 30 is machined with the corresponding pressure chambers (ammonia fuel needle valve pressure chamber 33, diesel needle valve pressure chamber 35, methanol needle valve pressure chamber 18) and nozzles (ammonia fuel needle valve nozzle 34, diesel needle valve nozzle 36, methanol needle valve nozzle 17) for each needle valve. Diesel fuel is pressurized in the methanol accumulator chamber 3 via the methanol interface 2, and then reaches the diesel needle valve accumulator chamber 16 via the methanol supply pipeline 6, completing the diesel fuel supply. Methanol is pressurized in methanol accumulator chamber 3 via diesel interface 1, and then reaches methanol needle valve oil chamber 15 via methanol supply pipeline 6, completing methanol supply. Ammonia fuel is pressurized in ammonia fuel accumulator chamber 21 via fastening cap 19, and then reaches ammonia fuel needle valve oil chamber 31 via ammonia fuel supply pipeline 25, completing ammonia fuel supply.

[0024] The dual solenoid valve control assembly 23 includes an upper solenoid valve reset spring 37, an upper section of the control valve core 38, a lower solenoid valve reset spring 39, a lower section of the control valve core 40, a lower solenoid valve armature 41, a lower solenoid valve 42, an upper solenoid valve 43, an upper solenoid valve armature 44, an upper return oil chamber 45, an upper return oil hole 46, an upper chamber of the control valve core 47, an internal oil passage of the control valve core 48, a lower return oil hole 49, a lower chamber of the control valve core 50, a lower return oil chamber 51, and a dual solenoid valve control assembly housing 52.

[0025] The upper solenoid valve 43 consists of an upper solenoid valve armature 44, an upper section of the control valve core 38, and an upper solenoid valve return spring 37. The lower solenoid valve 42 consists of a lower section of the control valve core 40, a lower solenoid valve armature 41, and a lower solenoid valve return spring 39. The upper solenoid valve 43 and the lower solenoid valve 42 are symmetrically installed in the control valve housing 52.

[0026] The dual solenoid valve control assembly housing 52 has flanges machined on both the top and bottom to house the upper solenoid valve return spring 37 and the lower solenoid valve return spring 39, respectively. These two return springs press the upper section 38 and lower section 40 of the control valve core into a single unit, confining them to the middle of the housing 52. The bottom of the upper section 38 has a protrusion that mates with the top groove of the lower section 40 to form a seal. The lower section 40 also contains an internal oil passage 48, which connects to the return oil line 38 of the diesel needle valve control chamber after the top seal is released. The upper section 38 and the housing 52 seal together to form an upper return oil chamber 45, and the lower section 40 and the housing 52 seal together to form a lower return oil chamber 51, both connecting to the servo oil tank via upper return oil holes 46 and lower return oil holes 49, respectively. The housing 52 of the dual solenoid valve control assembly also includes an upper control valve core chamber 47 and a lower control valve core chamber 50, which are sealed by the upper control valve core section 38 and the lower control valve core section 40, respectively.

[0027] The pilot control assembly 12 includes a diesel needle valve control chamber outlet throttle orifice 53, a diesel needle valve control chamber inlet throttle orifice 54, a diesel needle valve control chamber 55, a diesel needle valve return spring 56, a methanol needle valve control chamber inlet throttle orifice 57, a methanol needle valve control chamber 58, a methanol needle valve control chamber outlet throttle orifice 59, a methanol needle valve return spring 60, an ammonia fuel needle valve control chamber inlet throttle orifice 61, an ammonia fuel needle valve control chamber outlet throttle orifice 62, an ammonia fuel needle valve control chamber 63, a medium-meter orifice plate 64, a lower-meter orifice plate 65, an ammonia fuel needle valve return spring 66, and an ammonia fuel needle valve needle valve chamber 67.

[0028] The upper orifice plate 28 is machined with servo oil injection holes (second servo oil inlet line 10, pilot control component 11, nozzle 29) corresponding to each needle valve control chamber (diesel needle valve control chamber 52, methanol needle valve control chamber 57, ammonia fuel needle valve control chamber 67). Oil is supplied through the corresponding fuel throttling orifices (diesel needle valve control chamber inlet throttling orifice 51, methanol needle valve control chamber inlet throttling orifice 56, ammonia fuel needle valve control chamber inlet throttling orifice 60). The control chambers (diesel needle valve control chamber 52, ammonia fuel needle valve control chamber 63) of the methanol needle valve 17 and the third servo oil supply line 32 are sealed by their tops to the intermediate orifice plate 64. In the process of forming a seal, the control chamber 57 of the methanol needle valve 18 utilizes not only its top, nozzle 30, and lower orifice plate 64, but also a portion of the outer wall of the methanol needle valve 17. The methanol needle valve 18 and the needle valve chambers (methanol needle valve oil-holding chamber 17 and diesel needle valve accumulator chamber 18) of the third servo oil supply line 32 are formed by their cooperation with the nozzle 30. The diesel needle valve accumulator chamber 18 of the methanol needle valve 17 is formed by its outer wall cooperating with the inner wall of the methanol needle valve 18. The return springs (diesel needle valve return spring 53 and methanol needle valve return spring 59) of the methanol needle valve 17 and methanol needle valve 18 are placed in their corresponding needle valve control chambers (diesel needle valve control chamber 52 and methanol needle valve control chamber 57) to fit the isolation design of the nested arrangement of needle valves. The ammonia fuel needle valve return spring 65 of the third servo oil supply line 32 is placed in the ammonia fuel needle valve needle valve chamber 67.

[0029] The diesel / methanol / ammonia tri-fuel electronically controlled injector of the present invention, which is a nested dual needle valve and a parallel single needle valve, can achieve precise control of each needle valve through a dual solenoid valve control component, and complete the independent injection of each needle valve. It has three basic injection modes: diesel independent injection, methanol independent injection and ammonia fuel independent injection.

[0030] In the initial state, in the dual solenoid valve control assembly 12, the coils of the upper solenoid valve 43 and the lower solenoid valve 42 are both de-energized. The upper section 38 and the lower section 40 of the control valve core are placed in the middle position of the dual solenoid valve control assembly housing 52 due to the action of the upper solenoid valve return spring 33 and the lower solenoid valve return spring 39. The upper chamber 47 and the lower chamber 50 of the control valve core are sealed. The return oil line 38 of the diesel needle valve control chamber and the internal oil line 48 of the control valve core are also not connected.

[0031] Simultaneously, in the pilot control assembly 12, the high-pressure servo oil in each needle valve control chamber (diesel needle valve control chamber 55, methanol needle valve control chamber 58, ammonia fuel needle valve control chamber 63) provides downward pressure to the upper surface of the needle valve. This, in conjunction with the needle valve return springs (ammonia fuel needle valve return spring 63, methanol needle valve return spring 57, diesel needle valve return spring 53), causes each needle valve (diesel needle valve 16, methanol needle valve 17, ammonia fuel needle valve 33) to sit down, completing the sealing of each nozzle (diesel injection hole 37, methanol injection hole 20, ammonia fuel injection hole 34).

[0032] When the injector is in methanol injection mode, the coil of the upper solenoid valve 43 is energized and the coil of the lower solenoid valve 42 is de-energized. The coil of the upper solenoid valve 43 generates an upward attraction on the armature 44 of the upper solenoid valve, which drives the upper section 38 of the control valve core to move upward. The lower section 40 of the control valve core moves upward due to the action of the lower solenoid valve reset spring 39. During this process, the upward displacement limit of the upper section 38 of the control valve core is limited by the flange of the housing 52 of the dual solenoid valve control assembly at the top surface of the large end of the upper section 38 of the control valve core. The seal formed by the top recess of the lower section 40 of the control valve core and the bottom protrusion of the upper section 38 of the control valve core is not released because the seal length is greater than the displacement of a single solenoid valve. The seal length of the lower chamber 50 of the control valve core is less than the displacement, so the seal is released. The methanol needle valve control chamber 58 is connected to the lower return oil chamber 51 through the methanol needle valve control chamber return oil pipeline 27. Servo oil is discharged from the lower return oil hole 49. The hydraulic pressure in the methanol needle valve control chamber 58 gradually reduces the downward pressure on the methanol needle valve 19. When the resultant force of the downward pressure and the methanol needle valve reset spring 57 is less than the upward force of the high-pressure methanol on the methanol needle valve 19, the methanol needle valve 19 is lifted, and methanol is sprayed out from the methanol spray hole 20 through the methanol needle valve pressure chamber 21, and the injection begins.

[0033] When closed, the coil of the upper solenoid valve 43 is de-energized, and its upward attraction on the armature 44 of the upper solenoid valve disappears. The upper section 38 of the control valve core is driven by the return spring 33 of the upper solenoid valve to move the lower section 40 of the control valve core downward. When it moves to the force balance point between the upper section 38 of the control valve core and the return spring 39 of the lower solenoid valve, the lower section 40 of the control valve core stops at the initial position, the lower chamber 50 of the control valve core is sealed, the oil discharge process of the methanol needle valve control chamber 58 ends, and the servo oil re-pressurizes the methanol needle valve control chamber 58 through the first servo oil inlet oil passage 13 and the methanol needle valve control chamber inlet throttle hole 51. When the downward pressure generated by it and the return spring 57 of the methanol needle valve is greater than the upward force of the high-pressure methanol on the methanol needle valve 16, the methanol needle valve 16 sits down, and the oil injection process ends.

[0034] When the injector is in ammonia fuel injection mode, the coil of the upper solenoid valve 43 is de-energized and the coil of the lower solenoid valve 42 is energized. The coil of the lower solenoid valve 42 generates a downward attraction force on the lower solenoid valve return spring 39, which drives the lower section 40 of the control valve core to move downward. The upper section 38 of the control valve core moves downward due to the action of the upper solenoid valve return spring 33. During this process, the downward displacement limit of the lower section 40 of the control valve core is limited by the flange of the housing 52 of the dual solenoid valve control assembly at the lower top surface of the large end of the lower section 40 of the control valve core. The seal formed by the top recess of the lower section 40 of the control valve core and the bottom protrusion of the upper section 38 of the control valve core is not released because the seal length is greater than the displacement of a single solenoid valve. The seal length of the upper chamber 47 of the control valve core is less than the displacement, so the seal is released. The ammonia fuel needle valve control chamber 63 is connected to the upper return oil chamber 45 through the ammonia fuel needle valve control chamber return oil pipeline 29. Servo oil is discharged from the upper return oil hole 46. The pressure of the hydraulic pressure in the ammonia fuel needle valve control chamber 63 on the downward pressure of the ammonia fuel needle valve 35 gradually decreases. When the resultant force of the downward pressure and the ammonia fuel needle valve reset spring 63 is less than the upward force of the high-pressure ammonia fuel on the ammonia fuel needle valve 35, the ammonia fuel needle valve 35 is lifted, and the high-pressure ammonia fuel is ejected from the ammonia fuel injection hole 36 through the ammonia fuel needle valve pressure chamber 36, and the injection begins.

[0035] When closed, the coil of the lower solenoid valve 42 is de-energized, and its downward attraction to the lower solenoid valve return spring 39 disappears. The lower section 40 of the control valve core is driven by the lower solenoid valve return spring 39 to move the upper section 38 of the control valve core upward. When it moves to the force balance point between the upper solenoid valve return spring 33 and the lower solenoid valve return spring 39, the upper section 38 of the control valve core stops at the initial position, the upper chamber 47 of the control valve core is sealed, the oil discharge process of the ammonia fuel needle valve control chamber 63 ends, and the servo oil re-pressurizes the ammonia fuel needle valve control chamber 63 through the third servo oil inlet oil passage 32 and the ammonia fuel needle valve control chamber inlet throttle hole 63. When the downward pressure generated by it and the ammonia fuel needle valve return spring 63 is greater than the upward force of the high-pressure ammonia fuel on the ammonia fuel needle valve 35, the ammonia fuel needle valve 35 sits down, and the fuel injection process ends.

[0036] When the injector is in diesel fuel injection mode, the coils of the upper solenoid valve 43 and the lower solenoid valve 42 are simultaneously energized. The resulting attraction causes the armature 44 of the upper solenoid valve to move the upper section 38 of the control valve core upward, and the armature 41 of the lower solenoid valve to move the lower section 40 of the control valve core downward. The total displacement of the two solenoid valves causes the seal formed between the concave top of the lower section 40 of the control valve core and the protruding bottom of the upper section 38 of the control valve core to be released. The servo oil in the diesel needle valve control chamber 55 reaches the lower return oil chamber 51 through the diesel needle valve control chamber return oil line 38 and the internal oil line 48 of the control valve core, and then is discharged through the lower return oil hole 49. The hydraulic pressure in the diesel needle valve control chamber 55 gradually reduces the downward pressure on the diesel needle valve 16. When the resultant force of this downward pressure and the diesel needle valve return spring 54 is less than the upward force of the diesel fuel on the diesel needle valve 16, the diesel needle valve 16 is lifted, and the diesel fuel is injected from the diesel injection hole 20 through the diesel needle valve pressure chamber 21, and injection begins.

[0037] When closed, both solenoid valves (lower solenoid valve 42 and upper solenoid valve 43) are simultaneously de-energized. The upward attraction of upper solenoid valve 43 on upper solenoid valve armature 44 disappears, and the downward attraction of lower solenoid valve 42 on lower solenoid valve armature 41 disappears. The upper section 38 of the control valve core moves downward under the action of upper solenoid valve return spring 33, and the lower section 40 of the control valve core moves upward under the action of lower solenoid valve return spring 39. When it moves to the force balance point of upper solenoid valve return spring 33 and lower solenoid valve return spring 39, the upper section 38 and lower solenoid valve return spring 40... The lower section 40 of the control valve core stops at the initial position, and the seal between the top recess of the lower section 40 of the control valve core and the bottom protrusion of the upper section 38 of the control valve core is re-established. The oil discharge process of the diesel needle valve control chamber 55 is terminated. The servo oil from the first servo oil inlet 13 passes through the diesel needle valve control chamber inlet throttle hole 51 to re-pressurize the diesel needle valve control chamber 55. When the downward pressure generated by it and the diesel needle valve return spring 54 is greater than the upward force of the diesel fuel on the diesel needle valve 16, the diesel needle valve 16 sits down, and the fuel injection process ends.

[0038] By combining these three basic modes, the multi-needle valve parallel diesel / methanol / ammonia multi-fuel electronically controlled injector of the present invention can also perform combined injection or pre-main injection of diesel-methanol and diesel-ammonia fuels in a single injection process, solving the problem that methanol and ammonia fuels are not easy to ignite.

[0039] During diesel-methanol combined injection, both the upper solenoid valve 43 and the lower solenoid valve 42 are energized simultaneously. At this time, the injector is in diesel injection mode. The upper solenoid valve 43 remains energized, while the lower solenoid valve 42 switches from energized to de-energized. At this point, the lower solenoid valve stem 40 moves upward due to the action of the lower solenoid valve return spring 39. The seal formed by the top recess of the lower section 40 of the control valve core and the bottom protrusion of the upper section 38 of the control valve core is re-established, and the seal in the lower chamber 50 of the control valve core is released. The injector then skips the initial state from diesel injection mode and directly enters methanol injection mode. The process is similar during diesel-ammonia fuel combined injection.

Claims

1. A multi-fuel electronically controlled fuel injector with nested dual needle valves and a single needle valve in parallel, characterized by: The system includes a fastening cap and a tightening cap. The fastening cap is fixed to the outside of the tightening cap. Inside the tightening cap, from top to bottom, are arranged the accumulator chamber wall, oil circuit adjusting block, solenoid valve control component fastening block, upper orifice plate, middle orifice plate, lower orifice plate, and nozzle. The solenoid valve control component fastening block houses the dual solenoid valve control component. Pilot control components are installed in the middle orifice plate, lower orifice plate, and nozzle. The fastening cap contains diesel, methanol, and ammonia fuel interfaces. The accumulator chamber wall contains diesel, methanol, and ammonia fuel accumulator chambers. The diesel accumulator chamber is connected to the diesel interface. The alcohol accumulator chamber is connected to the methanol interface, and the ammonia fuel accumulator chamber is connected to the ammonia fuel interface. The pilot control component includes a diesel needle valve, a methanol needle valve, and an ammonia fuel needle valve. The diesel needle valve is located inside the methanol needle valve. The methanol needle valve and the nozzle form a methanol needle valve oil chamber, and the ammonia fuel needle valve and the nozzle form an ammonia fuel oil chamber. The methanol needle valve oil chamber is connected to the methanol accumulator chamber through a methanol supply pipeline. The diesel needle valve oil chamber is connected to the diesel accumulator chamber through a diesel supply pipeline, and the ammonia fuel oil chamber is connected to the ammonia fuel accumulator chamber through an ammonia fuel supply pipeline. The dual solenoid valve control assembly includes a housing, an upper solenoid valve, and a lower solenoid valve. The upper solenoid valve includes an upper solenoid valve armature, an upper section of a control valve core, and an upper solenoid valve return spring. The lower solenoid valve includes a lower solenoid valve armature, a lower section of a control valve core, and a lower solenoid valve return spring. The upper and lower sections of the control valve core are symmetrically mounted inside the housing. The upper section of the control valve core is fitted with the upper solenoid valve return spring, and the upper solenoid valve armature is mounted on the top of the upper section of the control valve core. The lower section of the control valve core is fitted with a lower solenoid valve return spring, and the lower solenoid valve armature is installed at the bottom of the lower section of the control valve core; the housing of the dual solenoid valve control assembly is respectively provided with an upper chamber of the control valve core, a lower chamber of the control valve core, an upper oil return hole, and a lower oil return hole. The lower section of the control valve core is provided with an internal oil passage of the control valve core. The upper section of the control valve core and the housing of the dual solenoid valve control assembly form an upper oil return chamber, and the lower section of the control valve core and the housing of the dual solenoid valve control assembly form a lower oil return chamber. The upper oil return chamber is connected to the upper oil return hole, and the lower oil return chamber is connected to the lower oil return hole. The main body of the diesel needle valve is located inside the nozzle, with its top passing through the lower orifice plate and situated within the middle orifice plate; the methanol needle valve is located inside the nozzle; the main body of the ammonia fuel needle valve is located inside the nozzle, with its top passing through the lower orifice plate and situated within the middle orifice plate; a diesel needle valve return spring is fitted on the top of the diesel needle valve, forming the diesel needle valve control chamber; a methanol needle valve return spring is fitted on the top of the methanol needle valve, forming the methanol needle valve control chamber; the top of the ammonia fuel needle valve and the middle orifice plate form the ammonia fuel needle valve control chamber; the ammonia fuel needle valve... The valve has a protrusion located inside the nozzle. An ammonia fuel needle valve with a return spring is fitted above the protrusion. The upper end of the return spring rests against the bottom of the intermediate orifice plate, forming the ammonia fuel needle valve chamber. The upper orifice plate has three servo oil supply lines: a first servo oil supply line, a second servo oil supply line, and a third servo oil supply line. The first servo oil supply line connects to the methanol needle valve control chamber via an inlet throttle orifice. The second servo oil supply line connects to the diesel needle valve control chamber via an inlet throttle orifice. The oil throttle orifice connects to the diesel needle valve control chamber. The third servo oil supply circuit connects to the ammonia fuel needle valve control chamber via the inlet throttle orifice. The intermediate orifice plate contains throttle orifices for the diesel needle valve's oil chamber and the ammonia fuel needle valve's oil chamber, respectively. The lower orifice plate contains a throttle orifice for the methanol needle valve's oil chamber. The diesel needle valve's oil chamber outlet throttle orifice connects to the diesel needle valve control chamber and its return oil circuit. The return oil circuit of the diesel needle valve control chamber is coordinated with the internal oil circuit of the control valve core. The methanol needle valve control chamber outlet throttles... The orifices are respectively connected to the methanol needle valve control chamber and the methanol needle valve control chamber return oil line. The methanol control chamber return oil line is connected to the lower chamber of the control valve core. The ammonia fuel needle valve control chamber oil outlet throttling orifice is respectively connected to the ammonia fuel needle valve control chamber and the ammonia fuel needle valve control chamber return oil line. The ammonia fuel needle valve control chamber return oil line is connected to the upper chamber of the control valve core. The nozzle at the bottom of the methanol needle valve is equipped with a methanol needle valve spray orifice. The nozzle at the bottom of the diesel needle valve is equipped with a diesel needle valve spray orifice. The nozzle at the bottom of the ammonia fuel needle valve is equipped with an ammonia fuel needle valve spray orifice.

2. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valves according to claim 1, characterized in that: In the initial state, in the dual solenoid valve control assembly, the coils of the upper and lower solenoid valves are de-energized. The upper and lower sections of the control valve core are placed in the middle of the dual solenoid valve control assembly housing due to the action of the upper and lower solenoid valve return springs. The upper and lower chambers of the control valve core are sealed, and the return oil line of the diesel needle valve control chamber is not connected to the internal oil line of the control valve core. In the pilot control assembly, the high-pressure servo oil in the diesel needle valve control chamber, methanol needle valve control chamber, and ammonia fuel needle valve control chamber provides downward pressure to the upper surface of the needle valve. This pressure, combined with the return springs of the ammonia fuel needle valve, methanol needle valve, and diesel needle valve, causes the diesel needle valve, methanol needle valve, and ammonia fuel needle valve to sit down, thus completing the sealing of the diesel injection port, methanol injection port, and ammonia fuel injection port.

3. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valves according to claim 1, characterized in that: In methanol injection mode, the upper solenoid valve coil is energized and the lower solenoid valve coil is de-energized. The upper solenoid valve coil exerts an upward attraction on the armature of the upper solenoid valve, causing the upper section of the control valve core to move upward. The lower section of the control valve core moves upward due to the action of the lower solenoid valve return spring. During this process, the upward displacement limit of the upper section of the control valve core is limited by the flange on the top surface of the large end of the upper section of the control valve core housing of the dual solenoid valve control assembly. The seal formed by the top recess of the lower section of the control valve core and the bottom protrusion of the upper section of the control valve core is not released because the seal length is greater than the displacement of a single solenoid valve. The seal length of the lower chamber of the control valve core is less than the displacement, so the seal is released. The methanol needle valve control chamber is connected to the lower return oil chamber through the methanol needle valve control chamber return oil pipeline. Servo oil is discharged from the lower return oil hole. The hydraulic pressure in the methanol needle valve control chamber gradually reduces the downward pressure on the methanol needle valve. When the resultant force of this downward pressure and the methanol needle valve return spring is less than the upward force of the high-pressure methanol on the methanol needle valve, the methanol needle valve is lifted, and methanol is injected from the methanol injection hole through the methanol needle valve pressure chamber, thus starting the injection process. When closed, the upper solenoid valve coil is de-energized, and its upward attraction on the upper solenoid valve armature disappears. The upper section of the control valve core is driven by the upper solenoid valve return spring to move the lower section of the control valve core downward. When it moves to the force balance point between the upper section of the control valve core and the lower solenoid valve return spring, the lower section of the control valve core stops at the initial position, the lower chamber of the control valve core is sealed, the oil discharge process of the methanol needle valve control chamber ends, and the servo oil re-pressurizes the methanol needle valve control chamber through the first servo oil inlet circuit and the methanol needle valve control chamber inlet throttle orifice. When the downward pressure generated by the servo oil and the methanol needle valve return spring is greater than the upward force of the high-pressure methanol on the methanol needle valve, the methanol needle valve sits down, and the oil injection process ends.

4. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valves according to claim 1, characterized in that: During ammonia fuel injection, the upper solenoid valve coil is de-energized, while the lower solenoid valve coil is energized. The lower solenoid valve coil exerts a downward force on the lower solenoid valve return spring, causing the lower section of the control valve core to move downward. The upper section of the control valve core also moves downward due to the force of the upper solenoid valve return spring. During this process, the downward displacement limit of the lower section of the control valve core is restricted by the flange on the lower top surface of the large end of the lower section of the control valve core, located on the housing of the dual solenoid valve control assembly. The seal formed by the recessed top of the lower section of the control valve core and the protruding bottom of the upper section of the control valve core has a sealing length greater than that of a single solenoid valve. The solenoid valve is displaced but not released. The sealing length of the upper chamber of the control valve core is less than the displacement, the seal is released, the ammonia fuel needle valve control chamber is connected to the upper return oil chamber through the ammonia fuel needle valve control chamber return oil pipeline, the servo oil is discharged from the upper return oil hole, the hydraulic pressure in the ammonia fuel needle valve control chamber gradually decreases the downward pressure on the ammonia fuel needle valve, when the resultant force of the downward pressure and the ammonia fuel needle valve reset spring is less than the upward force of the high pressure ammonia fuel on the ammonia fuel needle valve, the ammonia fuel needle valve is lifted, and the high pressure ammonia fuel is ejected from the ammonia fuel injection hole through the ammonia fuel needle valve pressure chamber, and injection begins; When closed, the lower solenoid valve coil is de-energized, and its downward attraction on the lower solenoid valve return spring disappears. The lower section of the control valve core is driven by the lower solenoid valve return spring to move the upper section of the control valve core upward. When it moves to the force balance point between the upper and lower solenoid valve return springs, the upper section of the control valve core stops at the initial position, the upper chamber of the control valve core is sealed, the oil discharge process of the ammonia fuel needle valve control chamber ends, and the servo oil re-pressurizes the ammonia fuel needle valve control chamber through the third servo oil inlet circuit and the ammonia fuel needle valve control chamber inlet throttle orifice. When the downward pressure generated by the servo oil and the ammonia fuel needle valve return spring is greater than the upward force of the high-pressure ammonia fuel on the ammonia fuel needle valve, the ammonia fuel needle valve sits down, and the fuel injection process ends.

5. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valves according to claim 1, characterized in that: When diesel fuel injection mode is activated, the coils of the upper and lower solenoid valves are energized simultaneously. The resulting attraction causes the armature of the upper solenoid valve to move the upper section of the control valve core upward, and the armature of the lower solenoid valve to move the lower section of the control valve core downward. The total displacement of the two solenoid valves causes the seal formed by the concave top of the lower section of the control valve core and the protruding bottom of the upper section of the control valve core to be released. The servo oil in the diesel needle valve control chamber reaches the lower return oil chamber through the return oil pipeline of the diesel needle valve control chamber and the oil circuit inside the control valve core, and then is discharged from the lower return oil hole. The hydraulic pressure in the diesel needle valve control chamber gradually reduces the downward pressure on the diesel needle valve. When the resultant force of this downward pressure and the return spring of the diesel needle valve is less than the upward force of the diesel fuel on the diesel needle valve, the diesel needle valve is lifted, and the diesel fuel is injected from the diesel injection hole through the diesel needle valve pressure chamber, thus starting the injection process. When closed, both the lower and upper solenoid valves are de-energized. The upward attraction of the upper solenoid valve on its armature disappears, and the downward attraction of the lower solenoid valve on its armature disappears. The upper section of the control valve core moves downward under the action of the upper solenoid valve's return spring, and the lower section of the control valve core moves upward under the action of the lower solenoid valve's return spring. When they reach the force balance point of the upper and lower solenoid valve's return springs, the upper and lower sections of the control valve core stop at their initial positions. The seal between the top recess of the lower section of the control valve core and the bottom protrusion of the upper section of the control valve core is re-established, and the oil discharge process of the diesel needle valve control chamber terminates. Servo oil from the first servo oil inlet path passes through the diesel needle valve control chamber inlet throttle orifice to re-pressurize the diesel needle valve control chamber. When the downward pressure generated by the servo oil and the diesel needle valve return spring is greater than the upward force of the diesel fuel on the diesel needle valve, the diesel needle valve sits down, and the fuel injection process ends.

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