Multi-fuel electronic control fuel injector with nested double needle valves connected in parallel with single needle valve

Abstract

The invention aims to provide a multi-fuel electronic control fuel injector with nested double needle valves connected in parallel with a single needle valve, and belongs to the field of internal combustion engines. Comprising different fuel connectors, a pressure storage cavity, a needle valve, a control assembly and the like. According to the structure, the diesel pressure storage cavity and other components are installed in a specific connection mode, the methanol needle valve is embedded in a spraying hole, and the double-electromagnetic-valve control assembly and the pilot control assembly work cooperatively. The needle valves are accurately controlled through the double-electromagnetic-valve control assembly, independent injection of diesel oil, methyl alcohol and ammonia fuel is achieved, multi-fuel combined injection or pre-main injection is conducted through mode combination, the problems that methyl alcohol and ammonia fuel are not prone to being ignited and multi-fuel injection control is difficult are solved, and the fuel injector can be applied to the field of internal combustion engine fuel injection and has a wide application prospect. The fuel utilization efficiency and the environmental protection performance of the engine are improved.

Description

Technical Field

[0001] The present invention relates to an internal combustion engine, in particular to a fuel injector of the internal combustion engine. Background Art

[0002] With increasingly stringent environmental protection requirements, the use of traditional fossil fuels faces huge challenges. Diesel is a commonly used internal combustion engine fuel, and the pollutants produced by its combustion have a certain impact on the environment. Methanol and ammonia fuels have become potential alternative fuels due to their advantages such as low emissions and renewability. However, the physical and chemical properties of methanol and ammonia fuels are quite different from those of diesel. For example, methanol has a large latent heat of vaporization and a high ignition temperature, and ammonia has a slow combustion rate and difficulty in ignition, which makes their application in engines face many problems, such as difficulty in ignition and unstable combustion. At the same time, achieving precise injection and flexible control of multiple fuels is also a technical challenge. Summary of the invention

[0003] The object of the present invention is to provide a multi-fuel electronically controlled fuel injector having a nested double needle valve in parallel with a single needle valve, which can solve the problems of poor ignition of methanol and ammonia fuels and difficulty in controlling multi-fuel injection.

[0004] The object of the present invention is achieved in that:

[0005] The multi-fuel electronically controlled fuel injector of the present invention with nested double needle valves and a single needle valve in parallel is characterized in that it comprises a fastening cap and an upper fastening cap, wherein the fastening cap is fixed to the outside of the upper fastening cap, and the upper fastening cap is provided with a pressure storage chamber wall, an oil circuit adjustment block, a solenoid valve control component fastening block, an upper orifice plate, a middle orifice plate, a lower orifice plate, and a nozzle in sequence from top to bottom, a double solenoid valve control component is installed in the solenoid valve control component fastening block, and a pilot control component is installed in the middle orifice plate, the lower orifice plate, and the nozzle; a diesel interface, a methanol interface, and an ammonia fuel interface are respectively provided in the fastening cap, and a diesel pressure storage chamber, a methanol pressure storage chamber, and an ammonia fuel pressure storage chamber are respectively provided in the pressure storage chamber wall. The diesel pressure accumulation chamber is connected to the diesel interface, the methanol pressure accumulation chamber is connected to the methanol interface, and the ammonia fuel pressure accumulation 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 storage chamber, the diesel needle valve and the methanol needle valve form a diesel needle valve oil storage chamber, the ammonia fuel needle valve and the nozzle form an ammonia fuel oil storage chamber, the methanol needle valve oil storage chamber is connected to the methanol pressure accumulation chamber through the methanol supply pipeline, the diesel needle valve oil storage chamber is connected to the diesel pressure accumulation chamber through the diesel supply pipeline, and the ammonia fuel oil storage chamber is connected to the ammonia fuel pressure accumulation chamber through the ammonia fuel supply pipeline.

[0006] The present invention may also include:

[0007] 1. The dual solenoid valve control assembly includes a dual solenoid valve control assembly 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 reset spring. The lower solenoid valve includes a lower solenoid valve armature, a lower section of a control valve core, and a lower solenoid valve reset spring. The upper section of the control valve core and the lower section of the control valve core are symmetrically installed in the dual solenoid valve control assembly housing. The upper section of the control valve core is covered with an upper solenoid valve reset spring. 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 sleeved with a lower solenoid valve reset spring, and the lower solenoid valve armature is installed at the bottom of the lower section of the control valve core; the upper chamber of the control valve core, the lower chamber of the control valve core, the upper oil return hole and the lower oil return hole are respectively arranged in the outer shell of the double solenoid valve control component, and the lower section of the control valve core is arranged with an internal oil circuit of the control valve core. The upper section of the control valve core and the outer shell of the double solenoid valve control component form an upper oil return chamber, and the lower section of the control valve core and the outer shell of the double solenoid valve control component 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 in the nozzle, and its top passes through the lower orifice plate and is located in the middle orifice plate; the methanol needle valve is located in the nozzle; the main body of the ammonia fuel needle valve is located in the nozzle, and its top passes through the lower orifice plate and is located in the middle orifice plate; the top of the diesel needle valve is covered with a diesel needle valve return spring, and its position forms a diesel needle valve control cavity; the diesel needle valve is located at the top of the methanol needle valve. The position of the methanol needle valve return spring forms a methanol needle valve control cavity, and the top of the ammonia fuel needle valve and the middle orifice plate form an ammonia fuel needle valve control cavity, and the ammonia fuel A protrusion is arranged on the material needle valve, and the position of the protrusion is located in the nozzle. The ammonia fuel needle valve sleeve above the protrusion is provided with an ammonia fuel needle valve reset spring. The upper end of the ammonia fuel needle valve reset spring is pressed against the bottom of the middle orifice plate, and the position where the ammonia fuel needle valve reset spring is located forms an ammonia fuel needle valve cavity. The upper orifice plate is respectively provided with a first servo oil supply oil circuit, a second servo oil supply oil circuit, and a third servo oil supply oil circuit. The first servo oil supply oil circuit is connected to the methanol needle valve control cavity through the methanol needle valve control cavity oil inlet throttling hole, and the second servo oil supply oil circuit is connected to the diesel needle valve control cavity through the diesel needle valve control cavity The oil inlet throttle hole is connected to the diesel needle valve control chamber, and the third servo oil supply oil circuit is connected to the ammonia fuel needle valve control chamber through the ammonia fuel needle valve control chamber oil inlet throttle hole; the diesel needle valve oil holding chamber oil outlet throttle hole and the ammonia fuel needle valve oil holding chamber oil outlet throttle hole are respectively arranged in the middle orifice plate, and the methanol needle valve oil holding chamber oil outlet throttle hole is arranged in the lower orifice plate. The diesel needle valve oil holding chamber oil outlet throttle hole is connected to the diesel needle valve control chamber and the diesel needle valve control chamber oil return oil circuit. The diesel needle valve control chamber oil return pipeline cooperates with the internal oil circuit of the control valve core, and the methanol needle valve control chamber oil outlet throttle hole The holes are respectively connected to the methanol needle valve control chamber and the methanol needle valve control chamber oil return pipeline, the methanol control chamber oil return pipeline is connected to the lower chamber of the control valve core, the ammonia fuel needle valve control chamber oil outlet throttling hole is respectively connected to the ammonia fuel needle valve control chamber and the ammonia fuel needle valve control chamber oil return pipeline, the ammonia fuel needle valve control chamber oil return pipeline is connected to the upper chamber of the control valve core; the nozzle at the bottom of the methanol needle valve is provided with a methanol needle valve spray hole, the nozzle at the bottom of the diesel needle valve is provided with a diesel needle valve spray hole, and the nozzle at the bottom of the ammonia fuel needle valve is provided with an ammonia fuel needle valve spray hole.

[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 in a de-energized state, the upper section of the control valve core and the lower section 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 solenoid valve return spring and the lower solenoid valve return spring, the upper chamber of the control valve core and the lower chamber of the control valve core are sealed, and the return oil pipeline of the diesel needle valve control chamber and the internal oil circuit of the control valve core are also in a disconnected state;

[0010] In the pilot control assembly, the high-pressure servo oil in the diesel needle valve control chamber, the methanol needle valve control chamber, and the ammonia fuel needle valve control chamber provides downward pressure to the upper top surface of the needle valve, and cooperates with the ammonia fuel needle valve return spring, the methanol needle valve return spring, and the diesel needle valve return spring to make the diesel needle valve, the methanol needle valve, and the ammonia fuel needle valve seated, completing the sealing of the diesel spray hole, the methanol spray hole, and the ammonia fuel spray hole.

[0011] 4. When the methanol injection mode is in progress, the upper solenoid valve coil is energized, and the lower solenoid valve coil is de-energized. The upper solenoid valve coil generates an upward attraction force on the upper solenoid valve armature, driving the upper section of the control valve core to move upward, and the lower section of the control valve core moves upward due to the action of the lower solenoid valve reset spring. In this process, the upward displacement limit of the upper section of the control valve core is limited by the flange of the double solenoid valve control component housing at the upper top surface of the large end of the upper section of the control valve core. The seal formed by the top depression of the lower section of the control valve core and the protruding part of the bottom of the upper section of the control valve core is not released because the sealing length is greater than the displacement of a single solenoid valve. The sealing length of the lower chamber of the control valve core is less than the displacement, the seal is released, and the methanol needle valve control chamber is connected to the lower return oil chamber through the methanol needle valve control chamber return oil pipeline. The servo oil leaks from the lower return oil hole, and the liquid pressure in the methanol needle valve control chamber gradually reduces the downward pressure on the methanol needle valve. When the combined force of the downward pressure and the methanol needle valve reset 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 from the methanol spray hole through the methanol needle valve pressure chamber, and the injection begins.

[0012] When closed, the upper solenoid valve coil loses power, and its upward attraction to the upper solenoid valve armature disappears. The upper section of the control valve core is driven by the upper solenoid valve reset 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 reset spring, the lower section of the control valve core stops at the initial position, the lower chamber of the control valve core is sealed, and the oil leakage process of the methanol needle valve control chamber is completed. The servo oil re-builds pressure in the methanol needle valve control chamber through the first servo oil inlet oil circuit and the methanol needle valve control chamber oil inlet throttle hole. When the downward pressure generated by it and the methanol needle valve reset spring is greater than the upward force of the high-pressure methanol on the methanol needle valve, the methanol needle valve falls into its seat, and the injection process is completed.

[0013] 5. When the ammonia fuel injection mode is in progress, the upper solenoid valve coil loses power, while the lower solenoid valve coil gains power. The lower solenoid valve coil exerts downward attraction on the lower solenoid valve reset spring, driving 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 reset spring. In this process, the downward displacement limit of the lower section of the control valve core is limited by the flange of the housing of the double solenoid valve control assembly at the lower top surface of the large end of the lower section of the control valve core. The seal formed by the concave top of the lower section of the control valve core and the protruding part of the bottom of the upper section of the control valve core has a longer sealing length than that of the single solenoid valve control assembly. When 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 with the upper return oil chamber through the ammonia fuel needle valve control chamber oil return pipeline, and the servo oil leaks out from the upper return oil hole. The downward pressure of the ammonia fuel needle valve on the liquid pressure in the ammonia fuel needle valve control chamber 3 gradually decreases. When the combined force of the downward pressure and the ammonia fuel needle valve return 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 spray hole through the ammonia fuel needle valve pressure chamber, and the injection begins;

[0014] When closed, the lower solenoid valve coil loses power, and its downward attraction to 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 solenoid valve return spring and the lower solenoid valve return spring, the upper section of the control valve core stops at the initial position, and the upper chamber of the control valve core is sealed. The oil leakage process of the ammonia fuel needle valve control chamber is completed, and the servo oil re-builds pressure in the ammonia fuel needle valve control chamber through the third servo oil inlet oil circuit and the ammonia fuel needle valve control chamber oil inlet throttle hole. When the downward pressure generated by it 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 falls into its seat, and the injection process is completed.

[0015] 6. When the diesel fuel injection mode is in progress, the upper solenoid valve and the lower solenoid valve coils are energized at the same time, and the generated attraction forces the upper solenoid valve armature to drive the upper section of the control valve core to move upward, and the lower solenoid valve armature to drive the lower section of the control valve core to move downward. The sum of the displacements generated by the two solenoid valves releases 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. The servo oil in the diesel needle valve control chamber passes through the diesel needle valve control chamber return oil pipeline and the internal oil circuit of the control valve core to reach the lower return oil chamber, and then leaks out from the lower return oil hole; the downward pressure of the diesel needle valve on the diesel needle valve by the liquid pressure in the diesel needle valve control chamber gradually decreases. When the combined force of the downward pressure and the diesel needle valve return spring 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 sprayed out from the diesel spray hole through the diesel needle valve pressure chamber, and the injection begins;

[0016] When closed, the lower solenoid valve and the upper solenoid valve lose power at the same time, the upward attraction of the upper solenoid valve on the upper solenoid valve armature disappears, and the downward attraction of the lower solenoid valve on the lower solenoid valve armature disappears. The upper section of the control valve core moves downward under the action of the upper solenoid valve return spring, and the lower section of the control valve core moves upward under the action of the lower solenoid valve return spring. When it moves to the force balance point of the upper solenoid valve return spring and the lower solenoid valve return spring, the upper section of the control valve core and the lower section of the control valve core stop at the initial position, and the seal between the top depression of the lower section of the control valve core and the bottom protrusion of the upper section of the control valve core is established again, and the oil leakage process of the diesel needle valve control chamber is terminated. The servo oil from the first servo oil inlet oil path passes through the diesel needle valve control chamber oil inlet throttle hole to re-build the pressure of the diesel needle valve control chamber. When the downward pressure generated by it 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 falls and the injection process ends.

[0017] The advantages of the present invention are as follows: the present invention uses a dual solenoid valve control assembly to accurately control each needle valve, thereby achieving independent injection of diesel, methanol and ammonia fuels, and performing multi-fuel combined injection or pre-main injection through mode combination, thereby solving the problem 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 to improve the engine's fuel utilization efficiency and environmental performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention;

[0019] Figure 2 It is a schematic diagram of the structure of a dual solenoid valve control component;

[0020] Figure 3 This is a schematic diagram of the pilot control component structure. DETAILED DESCRIPTION

[0021] The present invention is described in more detail below with reference to the accompanying drawings:

[0022] Combination Figure 1-3The multi-fuel electronically controlled fuel injector of the present invention is composed of a diesel interface 1, a methanol interface 2, a methanol pressure storage chamber 3, an outer wall of the pressure storage 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 storage chamber 15, a diesel needle valve oil storage chamber 16, a methanol needle valve spray hole 17, a methanol needle valve pressure chamber 18, and an ammonia The fuel interface 19, the fastening cap 20, the diesel pressure accumulation chamber 21, the ammonia fuel pressure accumulation chamber 22, the dual solenoid valve control assembly 23, the dual solenoid valve control assembly fastening block 24, the ammonia fuel supply pipeline 25, the ammonia fuel needle valve control chamber oil return pipeline 26, the methanol needle valve control chamber oil return pipeline 27, the upper orifice plate 28, the third servo oil supply pipeline 29, the nozzle 30, the ammonia fuel needle valve oil storage chamber 31, the ammonia fuel needle valve 32, the ammonia fuel needle valve pressure chamber 33, the ammonia fuel needle valve spray hole 34, the diesel needle valve pressure chamber 35 and the diesel needle valve spray hole 36 are composed.

[0023] The fastening cap 20, the outer wall of the pressure accumulator chamber 4, the oil circuit adjustment block 5, the upper orifice plate 28, the pilot control assembly 12 and the nozzle 30 are installed from top to bottom through the positioning pins, and the whole is wrapped in the diesel needle valve control chamber oil return oil circuit 8. The upper part is connected to the fastening cap 20 by threads, and the lower part is connected to the nozzle 30 by a bayonet. The dual solenoid valve control assembly 23 is wrapped in the dual solenoid valve control assembly fastening block 24 to form a whole. The methanol needle valve 13 is nested in the methanol needle valve 14 and placed in the reserved gap of the nozzle 30 together with the ammonia fuel 32. The pressure chambers (ammonia fuel needle valve pressure chamber 33, diesel needle valve pressure chamber 35, methanol needle valve pressure chamber 18) and spray holes (ammonia fuel needle valve spray hole 34, diesel needle valve spray hole 36, methanol needle valve spray hole 17) corresponding to each needle valve are processed at the bottom of the nozzle 30. Diesel is stored in the methanol pressure accumulator chamber 3 through the methanol interface 2, and then reaches the diesel needle valve pressure accumulator chamber 16 through the methanol supply pipeline 6 to complete the diesel supply. Methanol is pressurized in the methanol pressure storage chamber 3 through the diesel interface 1, and reaches the methanol needle valve oil storage chamber 15 through the methanol supply pipeline 6, completing the methanol supply. Ammonia fuel is pressurized in the ammonia fuel pressure storage chamber 21 through the fastening cap 19, and then reaches the ammonia fuel needle valve oil storage chamber 31 through the ammonia fuel supply pipeline 25, completing the ammonia fuel supply.

[0024] The dual solenoid valve control assembly 23 includes an upper solenoid valve return spring 37, an upper section of the control valve core 38, a lower solenoid valve return 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 oil return chamber 45, an upper oil return hole 46, an upper chamber of the control valve core 47, an internal oil circuit of the control valve core 48, a lower oil return hole 49, a lower chamber of the control valve core 50, a lower oil return chamber 51 and a dual solenoid valve control assembly housing 52.

[0025] The upper solenoid valve 43 is composed of an upper solenoid valve armature 44, an upper section of the control valve core 38 and an upper solenoid valve return spring 37, and the lower solenoid valve 42 is composed 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 double solenoid valve control assembly housing 52 is processed with flanges on the upper and lower parts to place the upper solenoid valve return spring 37 and the lower solenoid valve return spring 39 respectively. The two return springs press the control valve core upper section 38 and the control valve core lower section 40 into a whole and limit them in the middle of the double solenoid valve control assembly housing 52. The control valve core upper section 38 is processed with a protrusion at the bottom, which cooperates with the top groove of the control valve core lower section 40 to form a seal. The control valve core internal oil circuit 48 is also processed in the control valve core lower section 40, which is connected to the diesel needle valve control chamber oil return pipeline 38 after the top seal is released. The control valve core upper section 38 and the double solenoid valve control assembly housing 52 are sealed to form an upper oil return chamber 45, and the control valve core lower section 40 and the double solenoid valve control assembly housing 52 are sealed to form a lower oil return chamber 51, which are connected to the servo oil tank through the upper oil return hole 46 and the lower oil return hole 49 respectively. The housing 52 of the dual solenoid valve control assembly is also processed with a control valve core upper chamber 47 and a control valve core lower chamber 50, which are sealed by the control valve core upper section 38 and the control valve core lower section 40 respectively.

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

[0028] The upper orifice plate 28 is processed with servo oil filling holes (second servo oil inlet oil circuit 10, pilot control assembly 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 needle valve chamber 67), and the oil supply is completed through the fuel throttle holes (diesel needle valve control chamber oil inlet throttle hole 51, methanol needle valve control chamber oil inlet throttle hole 56, ammonia fuel needle valve control chamber oil inlet throttle hole 60) corresponding to each needle valve control chamber. 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 pipeline 32 are sealed by their tops and the middle orifice plate 64. In the process of forming a seal, the control chamber 57 of the methanol needle valve 18 not only uses its top, nozzle 30 and lower orifice plate 64, but also uses a part of the outer wall of the methanol needle valve 17. The needle valve chambers (methanol needle valve oil storage chamber 17, diesel needle valve pressure storage chamber 18) of the methanol needle valve 18 and the third servo oil supply pipeline 32 are obtained by cooperating with the nozzle 30, and the diesel needle valve pressure storage chamber 18 of the methanol needle valve 17 is obtained by cooperating with its outer wall and the inner wall of the methanol needle valve 18. The return springs (diesel needle valve return spring 53, methanol needle valve return spring 59) of the methanol needle valve 17 and the methanol needle valve 18 are placed in the corresponding needle valve control chambers (diesel needle valve control chamber 52, methanol needle valve control chamber 57) to match the isolation design of the needle valve nesting arrangement, and the ammonia fuel needle valve return spring 65 of the third servo oil supply pipeline 32 is placed in the ammonia fuel needle valve needle valve chamber 67.

[0029] The diesel / methanol / ammonia three-fuel electronically controlled injector with nested double needle valves and a single needle valve in parallel of the present invention can achieve precise control of each needle valve through a dual solenoid valve control component, complete independent injection of each needle valve, and has three basic injection modes: independent diesel injection, independent methanol injection, and independent ammonia fuel 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 in a de-energized state, the upper section 38 of the control valve core 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 of the control valve core and the lower chamber 50 of the control valve core are sealed, and the diesel needle valve control chamber return oil pipeline 38 and the internal oil circuit 48 of the control valve core are also in a disconnected state.

[0031] At the same time, 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 top surface of the needle valve, and cooperates with each needle valve return spring (ammonia fuel needle valve return spring 63, methanol needle valve return spring 57, diesel needle valve return spring 53) to make each needle valve (diesel needle valve 16, methanol needle valve 17, ammonia fuel needle valve 33) seated, completing the sealing of each nozzle (diesel spray hole 37, methanol spray hole 20, ammonia fuel spray 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 force on the upper solenoid valve armature 44, driving 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 return spring 39. During this process, the upward displacement limit of the control valve core upper section 38 is limited by the flange of the double solenoid valve control component housing 52 on the upper top surface of the large end of the control valve core upper section 38. The seal formed by the top depression of the control valve core lower section 40 and the bottom protrusion of the control valve core upper section 38 is not released because the sealing length is greater than the displacement of a single solenoid valve. The sealing length of the control valve core lower chamber 50 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 oil return line 27, and the servo oil leaks from the lower return oil hole 49. The liquid pressure in the methanol needle valve control chamber 58 gradually reduces the downward pressure on the methanol needle valve 19. When the combined 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 from the methanol spray hole 20 through the methanol needle valve pressure chamber 21 to start spraying.

[0033] When closed, the coil of the upper solenoid valve 43 loses power, and its upward attraction to the upper solenoid valve armature 44 disappears. The upper section 38 of the control valve core is driven by the upper solenoid valve reset spring 33 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 lower solenoid valve reset spring 39, the lower section 40 of the control valve core stops at the initial position, and the lower chamber 50 of the control valve core is sealed. The oil leakage process of the methanol needle valve control chamber 58 ends, and the servo oil re-builds pressure in the methanol needle valve control chamber 58 through the first servo oil inlet oil circuit 13 and the methanol needle valve control chamber oil inlet throttle hole 51. When the downward pressure generated by it and the methanol needle valve reset spring 57 is greater than the upward force of the high-pressure methanol on the methanol needle valve 16, the methanol needle valve 16 is seated, and the injection process ends.

[0034] When the injector performs ammonia fuel injection mode, the coil of the upper solenoid valve 43 loses power, while the coil of the lower solenoid valve 42 gains power. The coil of the lower solenoid valve 42 generates a downward attraction force on the lower solenoid valve return spring 39, driving 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. In this process, the downward displacement limit of the control valve core lower section 40 is limited by the flange of the dual solenoid valve control assembly housing 52 at the lower top surface of the large end of the control valve core lower section 40. The seal formed by the top depression of the control valve core lower section 40 and the protruding part of the bottom of the control valve core upper section 38 is not released because the sealing length is greater than the displacement of a single solenoid valve. The sealing length of the control valve core upper chamber 47 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 oil return pipeline 29, and the servo oil leaks from the upper return oil hole 46. The liquid pressure in the ammonia fuel needle valve control chamber 63 gradually reduces the downward pressure on the ammonia fuel needle valve 35. When the combined force of the downward pressure and the ammonia fuel needle valve return 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 sprayed from the ammonia fuel spray hole 36 through the ammonia fuel needle valve pressure chamber 36 to start spraying.

[0035] When closed, the coil of the lower solenoid valve 42 loses power, 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, and the upper chamber 47 of the control valve core is sealed. The oil leakage process of the ammonia fuel needle valve control chamber 63 ends, and the servo oil re-builds the pressure of the ammonia fuel needle valve control chamber 63 through the third servo oil inlet oil circuit 32 and the ammonia fuel needle valve control chamber oil 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 is seated, and the 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 energized at the same time, and the generated attraction forces the upper solenoid valve armature 44 to drive the upper section 38 of the control valve core to move upward, and the lower solenoid valve armature 41 to drive the lower section 40 of the control valve core to move downward. The sum of the displacements generated by the two solenoid valves causes the seal formed by the concave top of the control valve core lower section 40 and the protruding bottom of the control valve core upper section 38 to be released, and the servo oil in the diesel needle valve control chamber 55 reaches the lower oil return chamber 51 through the diesel needle valve control chamber oil return pipeline 38 and the control valve core internal oil circuit 48, and then leaks out from the lower oil return hole 49. The downward pressure of the diesel needle valve 16 by the liquid pressure in the diesel needle valve control chamber 55 gradually decreases. When the combined force of the 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 sprayed from the diesel spray hole 20 through the diesel needle valve pressure chamber 21, and the injection begins.

[0037] When closed, the two solenoid valves (lower solenoid valve 42 and upper solenoid valve 43) lose power at the same time, the upward attraction of the upper solenoid valve 43 on the upper solenoid valve armature 44 disappears, and the downward attraction of the lower solenoid valve 42 on the lower solenoid valve armature 41 disappears. The upper section 38 of the control valve core moves downward under the action of the upper solenoid valve return spring 33, and the lower section 40 of the control valve core moves upward under the action of the lower solenoid valve return spring 39. When moving 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 and The lower section 40 of the control valve core stops at the initial position, and the seal between the top depression 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 established again, and the oil leakage process of the diesel needle valve control chamber 55 is terminated. The servo oil is re-pressurized in the diesel needle valve control chamber 55 through the diesel needle valve control chamber oil inlet throttle hole 51 from the first servo oil inlet oil passage 13. When the downward pressure generated by the servo oil 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 is seated, and the injection process ends.

[0038] Through the combination of these three basic modes, the diesel / methanol / ammonia multi-fuel electronically controlled injector with multiple needle valves in parallel of the present invention can also perform a combined injection of diesel-methanol, diesel-ammonia fuel or a pre-main injection of multiple fuels in a single injection process, thereby solving the problem that methanol and ammonia fuels are difficult to ignite.

[0039] When performing diesel-methanol combined injection, the upper solenoid valve 43 and the lower solenoid valve 42 are energized at the same time, and the injector is in the diesel injection mode. Then the upper solenoid valve 43 remains energized, and the lower solenoid valve 42 changes from the energized state to the de-energized state. At this time, the lower solenoid valve stem 40 moves upward due to the action of the lower solenoid valve reset spring 39, and the seal formed by the top depression of the control valve core lower section 40 and the bottom protrusion of the control valve core upper section 38 is re-established, and the seal of the lower chamber 50 of the control valve core is released, and the injector skips the initial state from the diesel injection mode to the methanol injection mode directly. It is similar when performing diesel-ammonia fuel combined injection.

Claims

1. A multi-fuel electronically controlled fuel injector with nested double needle valves in parallel with a single needle valve, characterized by: It includes a fastening cap and an upper fastening cap. The fastening cap is fixed on the outside of the upper fastening cap. The upper fastening cap is provided with a pressure storage chamber wall, an oil circuit adjustment block, a solenoid valve control assembly fastening block, an upper orifice plate, a middle orifice plate, a lower orifice plate, and a nozzle from top to bottom. A double solenoid valve control assembly is installed in the fastening block of the solenoid valve control assembly. A pilot control assembly is installed in the middle orifice plate, the lower orifice plate, and the nozzle. A diesel interface, a methanol interface, and an ammonia fuel interface are respectively provided in the fastening cap. A diesel pressure storage chamber, a methanol pressure storage chamber, and an ammonia fuel pressure storage chamber are respectively provided in the pressure storage chamber wall. The diesel pressure storage chamber is connected to the diesel interface. The alcohol pressure storage chamber is connected to the methanol interface, and the ammonia fuel pressure storage 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 storage chamber, the diesel needle valve and the methanol needle valve form a diesel needle valve oil storage chamber, the ammonia fuel needle valve and the nozzle form an ammonia fuel oil storage chamber, the methanol needle valve oil storage chamber is connected to the methanol pressure storage chamber through the methanol supply pipeline, the diesel needle valve oil storage chamber is connected to the diesel pressure storage chamber through the diesel supply pipeline, and the ammonia fuel oil storage chamber is connected to the ammonia fuel pressure storage chamber through the ammonia fuel supply pipeline.

2. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valve according to claim 1 is characterized in that: The double solenoid valve control assembly comprises a double solenoid valve control assembly housing, an upper solenoid valve and a lower solenoid valve, wherein the upper solenoid valve comprises an upper solenoid valve armature, an upper section of a control valve core, and an upper solenoid valve reset spring, and the lower solenoid valve comprises a lower solenoid valve armature, a lower section of a control valve core, and a lower solenoid valve reset spring. The upper section of the control valve core and the lower section of the control valve core are symmetrically installed in the double solenoid valve control assembly housing, the upper section of the control valve core is sleeved with an upper solenoid valve reset spring, the upper solenoid valve armature is installed on the top of the upper section of the control valve core, and the control valve core is symmetrically installed in the upper section of the control valve core. The lower section of the control valve core is sleeved with a lower solenoid valve reset spring, and the lower solenoid valve armature is installed at the bottom of the lower section of the control valve core; the upper chamber of the control valve core, the lower chamber of the control valve core, the upper oil return hole and the lower oil return hole are respectively arranged in the shell of the double solenoid valve control component, and the lower section of the control valve core is arranged with an internal oil circuit of the control valve core. The upper section of the control valve core and the shell of the double solenoid valve control component form an upper oil return chamber, and the lower section of the control valve core and the shell of the double solenoid valve control component 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.

3. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valve according to claim 2 is characterized in that: The main body of the diesel needle valve is located in the nozzle, and its top passes through the lower orifice plate and is located in the middle orifice plate; the methanol needle valve is located in the nozzle; the main body of the ammonia fuel needle valve is located in the nozzle, and its top passes through the lower orifice plate and is located in the middle orifice plate; the top of the diesel needle valve is covered with a diesel needle valve return spring, and its position forms a diesel needle valve control cavity; the diesel needle valve is located at the top of the methanol needle valve. The position of the methanol needle valve return spring forms a methanol needle valve control cavity, and the top of the ammonia fuel needle valve and the middle orifice plate form an ammonia fuel needle valve control cavity, and the ammonia fuel needle valve The valve is provided with a protrusion, and the position of the protrusion is located in the nozzle. The ammonia fuel needle valve sleeve above the protrusion is provided with an ammonia fuel needle valve return spring. The upper end of the ammonia fuel needle valve return spring is pressed against the bottom of the middle orifice plate. The position where the ammonia fuel needle valve return spring is located forms an ammonia fuel needle valve cavity. The upper orifice plate is respectively provided with a first servo oil supply oil circuit, a second servo oil supply oil circuit, and a third servo oil supply oil circuit. The first servo oil supply oil circuit is connected to the methanol needle valve control cavity through the methanol needle valve control cavity oil inlet throttling hole, and the second servo oil supply oil circuit is connected to the diesel needle valve control cavity through the diesel needle valve control cavity oil inlet throttling hole. The oil throttle hole is connected to the diesel needle valve control chamber, and the third servo oil supply oil circuit is connected to the ammonia fuel needle valve control chamber through the ammonia fuel needle valve control chamber oil inlet throttle hole; the diesel needle valve oil storage chamber oil outlet throttle hole and the ammonia fuel needle valve oil storage chamber oil outlet throttle hole are respectively arranged in the middle orifice plate, and the methanol needle valve oil storage chamber oil outlet throttle hole is arranged in the lower orifice plate. The diesel needle valve oil storage chamber oil outlet throttle hole connects the diesel needle valve control chamber and the diesel needle valve control chamber oil return oil circuit. The diesel needle valve control chamber oil return pipeline cooperates with the internal oil circuit of the control valve core. The methanol needle valve control chamber oil outlet throttle hole The holes are respectively connected to the methanol needle valve control chamber and the methanol needle valve control chamber oil return pipeline, the methanol control chamber oil return pipeline is connected to the lower chamber of the control valve core, the ammonia fuel needle valve control chamber oil outlet throttling hole is respectively connected to the ammonia fuel needle valve control chamber and the ammonia fuel needle valve control chamber oil return pipeline, the ammonia fuel needle valve control chamber oil return pipeline is connected to the upper chamber of the control valve core; the nozzle at the bottom of the methanol needle valve is provided with a methanol needle valve spray hole, the nozzle at the bottom of the diesel needle valve is provided with a diesel needle valve spray hole, and the nozzle at the bottom of the ammonia fuel needle valve is provided with an ammonia fuel needle valve spray hole.

4. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valve according to claim 3 is characterized by: 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 in a power-off state, the upper section of the control valve core and the lower section 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 solenoid valve return spring and the lower solenoid valve return spring, the upper chamber of the control valve core and the lower chamber of the control valve core are sealed, and the diesel needle valve control chamber oil return pipeline and the internal oil circuit of the control valve core are also in a disconnected state; In the pilot control assembly, the high-pressure servo oil in the diesel needle valve control chamber, the methanol needle valve control chamber, and the ammonia fuel needle valve control chamber provides downward pressure to the upper top surface of the needle valve, and cooperates with the ammonia fuel needle valve return spring, the methanol needle valve return spring, and the diesel needle valve return spring to make the diesel needle valve, the methanol needle valve, and the ammonia fuel needle valve seated, completing the sealing of the diesel spray hole, the methanol spray hole, and the ammonia fuel spray hole.

5. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valve according to claim 3 is characterized by: When the methanol injection mode is in progress, the upper solenoid valve coil is energized, and the lower solenoid valve coil is de-energized. The upper solenoid valve coil generates an upward attraction force on the upper solenoid valve armature, driving the upper section of the control valve core to move upward, and the lower section of the control valve core moves upward due to the action of the lower solenoid valve reset spring; in this process, the upward displacement limit of the upper section of the control valve core is limited by the flange of the double solenoid valve control component housing at the upper top surface of the large end of the upper section of the control valve core, and the seal formed by the top depression of the lower section of the control valve core and the protruding part of the bottom of the upper section of the control valve core is not released because the sealing length is greater than the displacement of a single solenoid valve, and the sealing length of the lower chamber of the control valve core is less than the displacement, the seal is released, and the methanol needle valve control chamber is connected to the lower return oil chamber through the methanol needle valve control chamber return oil pipeline, and the servo oil leaks from the lower return oil hole. The downward pressure of the methanol needle valve on the methanol needle valve by the liquid pressure in the methanol needle valve control chamber gradually decreases. When the combined force of the downward pressure and the methanol needle valve reset 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 from the methanol spray hole through the methanol needle valve pressure chamber, and the injection begins; When closed, the upper solenoid valve coil loses power, and its upward attraction to the upper solenoid valve armature disappears. The upper section of the control valve core is driven by the upper solenoid valve reset 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 reset spring, the lower section of the control valve core stops at the initial position, the lower chamber of the control valve core is sealed, and the oil leakage process of the methanol needle valve control chamber is completed. The servo oil re-builds pressure in the methanol needle valve control chamber through the first servo oil inlet oil circuit and the methanol needle valve control chamber oil inlet throttle hole. When the downward pressure generated by it and the methanol needle valve reset spring is greater than the upward force of the high-pressure methanol on the methanol needle valve, the methanol needle valve falls into its seat, and the injection process is completed.

6. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valve according to claim 3 is characterized by: When the ammonia fuel injection mode is in progress, the upper solenoid valve coil loses power, while the lower solenoid valve coil gains power. The lower solenoid valve coil exerts a downward attraction on the lower solenoid valve return spring, driving 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. In this process, the downward displacement limit of the lower section of the control valve core is limited by the flange of the housing of the dual solenoid valve control assembly at the lower top surface of the large end of the lower section of the control valve core. The seal formed by the concave top of the lower section of the control valve core and the protruding part of the bottom of the upper section of the control valve core has a sealing length greater than that of a single 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 with the upper return oil chamber through the ammonia fuel needle valve control chamber oil return pipeline, the servo oil leaks from the upper return oil hole, and the downward pressure of the ammonia fuel needle valve on the liquid pressure in the ammonia fuel needle valve control chamber 3 gradually decreases. When the combined force of the downward pressure and the ammonia fuel needle valve return 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 from the ammonia fuel spray hole through the ammonia fuel needle valve pressure chamber, and the injection begins; When closed, the lower solenoid valve coil loses power, and its downward attraction to 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 solenoid valve return spring and the lower solenoid valve return spring, the upper section of the control valve core stops at the initial position, and the upper chamber of the control valve core is sealed. The oil leakage process of the ammonia fuel needle valve control chamber is completed, and the servo oil re-builds pressure in the ammonia fuel needle valve control chamber through the third servo oil inlet oil circuit and the ammonia fuel needle valve control chamber oil inlet throttle hole. When the downward pressure generated by it 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 falls into its seat, and the injection process is completed.

7. The multi-fuel electronically controlled fuel injector with nested double needle valves and parallel single needle valve according to claim 3 is characterized by: When the diesel fuel injection mode is in progress, the upper solenoid valve and the lower solenoid valve coils are energized at the same time, and the generated attraction forces the upper solenoid valve armature to drive the upper section of the control valve core to move upward, and the lower solenoid valve armature to drive the lower section of the control valve core to move downward. The sum of the displacements generated by the two solenoid valves releases 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. The servo oil in the diesel needle valve control chamber reaches the lower oil return chamber through the diesel needle valve control chamber return oil pipeline and the internal oil circuit of the control valve core, and then leaks out from the lower oil return hole. The downward pressure of the diesel needle valve on the diesel needle valve by the liquid pressure in the diesel needle valve control chamber gradually decreases. When the combined force of the downward pressure and the diesel needle valve return spring 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 sprayed out from the diesel spray hole through the diesel needle valve pressure chamber, and the injection begins. When closed, the lower solenoid valve and the upper solenoid valve lose power at the same time, the upward attraction of the upper solenoid valve on the upper solenoid valve armature disappears, and the downward attraction of the lower solenoid valve on the lower solenoid valve armature disappears. The upper section of the control valve core moves downward under the action of the upper solenoid valve return spring, and the lower section of the control valve core moves upward under the action of the lower solenoid valve return spring. When it moves to the force balance point of the upper solenoid valve return spring and the lower solenoid valve return spring, the upper section of the control valve core and the lower section of the control valve core stop at the initial position, and the seal between the top depression of the lower section of the control valve core and the bottom protrusion of the upper section of the control valve core is established again, and the oil leakage process of the diesel needle valve control chamber is terminated. The servo oil from the first servo oil inlet oil path passes through the diesel needle valve control chamber oil inlet throttle hole to re-build the pressure of the diesel needle valve control chamber. When the downward pressure generated by it 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 falls and the injection process ends.

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