Common rail pump of ammonia fuel engine

Abstract

The invention provides a common rail pump of an ammonia fuel engine. The common rail pump comprises a pump body assembly, a pump cover assembly, a pressure control valve, a safety valve, a plunger and barrel assembly, an ammonia inlet and outlet valve assembly, a guide piston assembly and a cam shaft. The pump cover assembly is mounted at the upper part of the pump body assembly and is connected with the pump body assembly into a whole through a bolt; the pressure control valve is fixed on the pump cover through a screw; the safety valve is installed on the pump cover, and a plunger and barrel assembly, an ammonia inlet and outlet valve assembly, a plunger spring, a plunger spring seat and a guide piston assembly are sequentially installed in a vertical middle hole of the pump body from top to bottom. The cam shaft is installed in the horizontal center hole of the pump body and provided with a plurality of cams corresponding to the guide piston assemblies arranged in the vertical center holes of the pump body respectively. According to the technical scheme, the method can adapt to the characteristics of ammonia fuel, overcomes the technical difficulties of gas-liquid phase change conversion, frictional wear, safety design and the like, meets the development requirements of an ammonia fuel engine, and has good safety, stability and reliability.

Description

Technical Field

[0001] The invention belongs to the technical field of engines, and in particular relates to a common rail pump for an ammonia fuel engine. Background Art

[0002] Global warming is becoming increasingly serious, and annual carbon emissions remain high. The strategies of "carbon peak" and "carbon neutrality" have become the themes of development in today's world. As the dominant position of fossil energy such as oil and natural gas gradually weakens, it is the consensus of countries around the world to develop and utilize alternative energy sources to transition the global energy structure system to a sustainable development and renewable energy era. Ammonia, as a fuel, has become increasingly popular with its many advantages such as zero carbon and strong availability. It has fully demonstrated its potential to become a future marine fuel and has attracted a large number of researchers at home and abroad to conduct research on ammonia fuel internal combustion engines, among which high-pressure direct injection in the cylinder is a very important technical route. It can be seen that it is imperative to develop an ammonia fuel high-pressure injection system to promote the research and development of ammonia fuel internal combustion engines.

[0003] The common rail system has the advantages of flexible injection mode and is widely used in engines. It is also one of the current development directions of ammonia engine fuel injection system. The common rail pump is one of the important components of the common rail system, and its performance directly affects the working condition of the common rail system. Ammonia fuel is quite different from diesel fuel. The viscosity of ammonia fuel is lower, and the friction and wear of moving parts in contact with ammonia in the common rail system will be more serious; ammonia fuel is corrosive, and many metals and non-metallic materials are not resistant to ammonia corrosion; ammonia fuel is toxic and flammable and explosive, and it cannot leak. Before maintenance, it is also necessary to empty the residual ammonia fuel in the common rail system; ammonia fuel is prone to gas-liquid phase change, and the latent heat of vaporization of ammonia fuel is large. Ammonia fuel needs to remain in liquid state in the common rail system during operation. If vaporization occurs, it will cause cavitation, gas blockage, heat absorption and icing and other problems.

[0004] Therefore, how to provide an ammonia fuel engine common rail pump that can adapt to the characteristics of ammonia fuel, overcome technical difficulties such as gas-liquid phase change, friction and wear, and safety design, and meet the development needs of ammonia fuel engines has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] The embodiment of the present invention provides an ammonia fuel engine common rail pump, which can adapt to the characteristics of ammonia fuel, overcome technical difficulties such as gas-liquid phase change conversion, friction and wear, and safety design, meet the development needs of ammonia fuel engines, and has good safety, stability and reliability.

[0006] In an embodiment of the present invention, an ammonia fuel engine common rail pump is provided, comprising: a pump body assembly 1, a pump cover assembly 2, a pressure control valve 3, a safety valve 4, a plunger pair 5, an ammonia inlet and outlet valve assembly 6, a guide piston assembly 7 and a camshaft 8.

[0007] The pump body group 1 includes: a pump body 11 with a horizontal center hole and a plurality of vertical center holes connected to the horizontal center hole, a bearing 12 installed in the horizontal center hole of the pump body 11, an ammonia inlet connector 13 fixedly connected to the pump body 11 by screws, and an oil inlet connector 14 installed on the pump body 11.

[0008] The pump cover assembly 2 is installed on the upper part of the pump body assembly 1 and connected to the pump body assembly 1 as a whole by bolts; the pump cover assembly 2 includes: a pump cover 21, a first plug 22, a second plug 23, a third plug 24, an ammonia outlet joint 25 and an abnormal leakage joint 26;

[0009] The pressure control valve 3 comprises: a valve body 31 , a sliding valve pair 32 , a spring 33 , a spring seat 34 , an adjusting screw 35 , a nut 36 and a proportional solenoid 37 , which is fixed to the pump cover 21 by screws; the sliding valve pair 32 comprises a valve core 321 and a valve sleeve 322 .

[0010] The safety valve 4 is installed on the pump cover 21, and includes: a safety valve body 41, a safety valve core 42, a safety valve spring 43, a pressure regulating gasket 44 and a safety valve connector 45;

[0011] The plunger pair 5, the ammonia inlet and outlet valve assembly 6, the plunger spring, the plunger spring seat and the guide piston assembly 7 are installed in the vertical middle hole of the pump body 11 from top to bottom in sequence; the plunger pair 5 includes: a plunger sleeve 51 and a plunger 52 in the plunger sleeve 51; the ammonia inlet and outlet valve assembly 6 includes: an ammonia inlet valve spring seat 61, an ammonia inlet valve spring 62, an ammonia inlet valve 63, a valve seat 64, an ammonia outlet valve 65, an ammonia outlet valve spring 66, and an ammonia outlet valve spring seat 67;

[0012] The camshaft 8 is installed in the horizontal center hole of the pump body 11, and the camshaft 8 is provided with a plurality of cams corresponding to the guide piston assemblies 7 provided in the vertical center holes of the pump body 11;

[0013] The plunger pair 5, the inlet and outlet ammonia valve assembly 6 and the pump cover assembly 2 are connected as a whole by bolts; the plunger pair 5 and the inlet and outlet ammonia valve assembly 6, and the inlet and outlet ammonia valve assembly 6 and the pump cover assembly 2 are positioned by positioning pins.

[0014] Furthermore, the common rail pump comprises:

[0015] The ammonia inlet joint 13 is designed with an ammonia fuel inlet A1, an ammonia fuel hole A2, a sealing boss A3 and an abnormal leakage fuel collection annular groove A4; the pump body 11 is designed with an ammonia fuel hole B1, and each vertical center hole of the pump body 11 is designed with an ammonia fuel annular groove B2 connected to the ammonia fuel hole B1, the pump body 11 is designed with a sealing oil hole B3 connected to the oil inlet joint 14, the pump body 11 is designed with an air hole B4 to connect multiple vertical center holes inside the pump body 11, the pump body 11 is designed with a lubricating oil inlet B5 and a lubricating oil hole B6, the upper end surface of the pump body 11 is designed with an abnormal leakage fuel collection groove B7, and the pump body 11 is designed with an abnormal leakage fuel collection hole B8 connecting the abnormal leakage fuel collection annular groove A4 and the abnormal leakage fuel collection groove B7;

[0016] The outer circle of the valve seat 64 is designed with an ammonia fuel annular groove C1, and the end of the valve seat 64 that contacts the plunger pair 5 is designed with an ammonia fuel annular groove C2. The valve seat 64 is designed with multiple ammonia fuel holes C3 that connect the ammonia fuel annular groove C1 and the ammonia fuel annular groove C2. The valve seat 64 is designed with a cavity C4 that accommodates the ammonia outlet valve 65. The valve seat 64 is designed with an ammonia fuel hole C5 that is connected to the cavity C4. The valve seat 64 is designed with an ammonia fuel hole C6, an abnormal leakage fuel collection hole C7, and an ammonia fuel reflux hole C8. The abnormal leakage fuel collection hole C7 is connected to the abnormal leakage fuel collection groove B7; the ammonia inlet valve 63 is designed with an ammonia fuel hole D1 and a cavity D2 that accommodates the ammonia inlet valve spring 62; the ammonia outlet valve 65 is designed with an ammonia fuel hole E1 and a cavity E2 that accommodates the ammonia outlet valve spring 66; the ammonia outlet valve spring seat 67 is designed with an ammonia fuel hole F1 and a cavity F2 that accommodates the ammonia outlet valve spring 66;

[0017] The plunger sleeve 51 is designed with a sealing oil ring groove G1 on its outer circle, a sealing oil ring groove G2 and an ammonia fuel ring groove G3 are designed in the middle hole of the plunger sleeve 51, a sealing oil hole G4 is designed on the plunger sleeve 51 to connect the sealing oil ring groove G1 and the sealing oil ring groove G2, an ammonia inlet hole G5 is designed on the plunger sleeve 51 to connect the ammonia fuel hole C6 and the ammonia fuel ring groove G3, and an ammonia fuel return hole G6 is designed on the plunger sleeve 51 to connect the ammonia fuel return hole C8 and the ammonia fuel ring groove G3; a plurality of tiny ring grooves H1 are designed on the outer circle of the plunger 52, and a coating with good self-lubricating property is plated on the outer circle surface of the plunger 52, and the plunger sleeve 51, the plunger 52 and the ammonia outlet valve 65 cooperate to form a plunger cavity H2;

[0018] The pump cover 21 is designed with an ammonia fuel volume cavity K1, the pump cover 21 is designed with an ammonia fuel hole K2 connecting the ammonia fuel hole F1 and the ammonia fuel volume cavity K1, the pump cover 21 is designed with an ammonia fuel reflux outlet K3, the pump cover 21 is designed with an ammonia fuel reflux hole K4 connecting the ammonia fuel reflux hole C8 and the ammonia fuel reflux outlet K3, the pump cover 21 is designed with a sealing boss K5, the pump cover 21 is designed with an abnormal leakage fuel outlet K6, the pump cover 21 is designed with an abnormal leakage fuel collection hole K7 connecting the abnormal leakage collection ring groove L1 and the abnormal leakage fuel outlet K6, the pump cover 21 is designed with an abnormal leakage fuel collection hole K8 connecting the abnormal leakage fuel collection hole K8 The leaking fuel collection groove B7 and the abnormal leaking fuel outlet K6, the pump cover 21 is designed with an abnormal leaking fuel collection hole K9, and the ammonia fuel leaking from the sealing surface between the ammonia outlet connector 25 and the pump cover 21 is introduced into the abnormal leaking fuel collection groove B7, the pump cover 21 is designed with abnormal leaking fuel collection holes K10, abnormal leaking fuel collection holes K11, abnormal leaking fuel collection holes K12, abnormal leaking fuel collection holes K13, abnormal leaking fuel collection holes K14, and the pump cover 21 is designed with a pressure sensor interface K15. If it is necessary to monitor the pressure in the ammonia fuel volume cavity of the pump cover, remove the plug 22 and replace it with a pressure sensor;

[0019] The pressure control valve 3 is designed with an abnormal leakage fuel collection ring groove L1, a sealing boss L2, and an ammonia fuel volume chamber L3. The pressure control valve 3 is designed with an ammonia fuel hole L4 connecting the ammonia fuel volume chamber L3 and the ammonia fuel volume chamber K1. The pressure control valve 3 is designed with a flow control window L5, an ammonia fuel volume chamber L6, and an ammonia fuel volume chamber L7. The pressure control valve 3 is designed with an ammonia fuel hole L8 connecting the ammonia fuel volume chamber L6 and the ammonia fuel volume chamber L7. The pressure control valve 3 is designed with an ammonia fuel outlet L9 , an ammonia fuel hole L10 is designed to connect the ammonia fuel volume chamber L7 and the ammonia fuel outlet L9, the pressure control valve 3 is designed with a leakage fuel collection chamber L11, a leakage fuel collection chamber L12, and a leakage fuel outlet L13, the pressure control valve 3 is designed with an ammonia fuel hole L14 to connect the leakage fuel collection chamber L11 and the leakage fuel collection chamber L12, and an ammonia fuel hole L15 is designed to connect the leakage fuel collection chamber L12 and the leakage fuel outlet L13, and the proportional solenoid 37 adopts an explosion-proof design;

[0020] The safety valve body 41 is designed with an ammonia fuel hole M1 ; the safety valve core 42 is designed with an ammonia fuel hole M2 ; and the safety valve connector 45 is designed with an ammonia fuel hole M3 .

[0021] Furthermore, the ammonia fuel inlet A1, the ammonia fuel hole A2, the ammonia fuel hole B1, the ammonia fuel annular groove B2, the ammonia fuel annular groove C1, the ammonia fuel hole C3 and the ammonia fuel annular groove C2 form a low-pressure ammonia fuel supply flow channel N. The low-pressure ammonia fuel flows from the ammonia fuel inlet A1 through the low-pressure ammonia fuel supply flow channel N to the ammonia fuel annular groove C2, and then enters the plunger cavity H2 through the ammonia inlet valve 63;

[0022] The ammonia fuel hole C6, the ammonia inlet hole G5, the ammonia fuel ring groove G3, the ammonia fuel reflux hole G6, the ammonia fuel reflux hole C8, the ammonia fuel reflux hole K4 and the ammonia fuel reflux outlet K3 constitute a low-pressure ammonia fuel reflux flow channel P. The low-pressure ammonia fuel in the channel formed by the ammonia fuel ring groove B2 and the ammonia fuel ring groove C1 enters the ammonia fuel ring groove G3 through the ammonia fuel hole C6 and the ammonia inlet hole G5, merges with the ammonia fuel leaking from the plunger cavity H2 through the gap of the plunger couple 5 to the ammonia fuel ring groove G3, and finally enters the ammonia fuel tank through the ammonia fuel reflux hole G6, the ammonia fuel reflux hole C8, the ammonia fuel reflux hole K4 and the ammonia fuel reflux outlet K3.

[0023] Further, the ammonia fuel hole D1, the ammonia fuel hole C5, the ammonia fuel hole E1, the ammonia fuel hole F1, the ammonia fuel hole K2 and the ammonia fuel volume cavity K1 constitute a high-pressure ammonia fuel flow channel Q. After the ammonia fuel is pressurized by the plunger 52, it enters the ammonia fuel volume cavity K1 through the high-pressure ammonia fuel flow channel Q; the high-pressure ammonia fuel in the ammonia fuel volume cavity K1 is delivered to the common rail pipe through the ammonia outlet joint 25 on the one hand, and on the other hand, it passes through the ammonia fuel discharge flow channel R composed of the ammonia fuel hole L4, the ammonia fuel volume cavity L3, the flow control window L5, the ammonia fuel volume cavity L6, the ammonia fuel hole L8, the ammonia fuel volume cavity L7, the ammonia fuel hole L10 and the ammonia fuel outlet L9, and finally flows back to the ammonia fuel collection tank, and the discharge ammonia fuel flow rate is adjusted by the pressure control valve 3;

[0024] The leakage fuel collection chamber L11, the ammonia fuel hole L14, the leakage fuel collection chamber L12, the ammonia fuel hole L15 and the leakage fuel outlet L13 constitute an ammonia fuel leakage collection flow channel S, which collects the ammonia fuel leaking from the gap of the sliding valve pair 32. The ammonia fuel in the ammonia fuel leakage collection flow channel S is designed with back pressure to ensure that the liquid ammonia does not vaporize.

[0025] Furthermore, the oil inlet joint 14, the sealing oil hole B3, the sealing oil ring groove G1, the sealing oil hole G4 and the sealing oil ring groove G2 constitute a sealing oil passage T for introducing the sealing oil into the sealing oil ring groove G2, and the sealing oil pressure is greater than the low-pressure ammonia fuel pressure at the inlet of the common rail pump to prevent leakage of ammonia fuel.

[0026] Furthermore, the abnormal leakage fuel collecting hole C7, the abnormal leakage fuel collecting hole B8, the abnormal leakage fuel collecting groove B7, the abnormal leakage fuel collecting hole K7, the abnormal leakage fuel collecting hole K8, the abnormal leakage fuel collecting hole K9, the abnormal leakage fuel collecting hole K10, the abnormal leakage fuel collecting hole K11, the abnormal leakage fuel collecting hole K12, the abnormal leakage fuel collecting hole K13, the abnormal leakage fuel collecting hole K14 and the abnormal leakage fuel outlet K6 constitute the abnormal leakage fuel collecting channel U, and the fuel abnormally leaked inside the common rail pump is discharged from the abnormal leakage fuel outlet K6 and finally flows into the ammonia fuel collection tank.

[0027] Furthermore, the common rail pump adopts a two-seal design to prevent leakage of ammonia fuel. An abnormal leakage fuel collection flow channel U is designed between the first seal and the second seal. If the first seal fails, the leaked ammonia fuel is discharged to the ammonia fuel collection tank through the abnormal leakage fuel collection flow channel U; the inner side of the abnormal leakage fuel collection annular groove A4 is a first seal formed by the sealing boss A3 and the sealing plane of the pump body 11, and a sealing ring is arranged on the outer side as a second seal; the inner side of the leakage fuel collection annular groove L1 is a first seal formed by the sealing boss L2 and the sealing boss K5, and a sealing ring is arranged on the outer side as a second seal;

[0028] The first plug 22, the second plug 23 and the third plug 24 are all provided with sealing rings as the second seal, and the sealing cone surface of the steel ball and the pump cover 21 constitute the first seal; the sealing spherical surface of the safety valve 4 and the sealing cone surface of the pump cover 21 constitute the first seal, and a sealing ring is provided between the safety valve 4 and the pump cover 21 as the second seal; a sealing ring is designed on the outer circle of the valve seat 64 as the first seal, and a sealing ring is designed on the upper end surface of the pump body 11 as the second seal; a sealing ring is provided in the gap between the plunger and the pair 5 as the second seal, and the sealing oil in the gap between the pair serves as the first seal.

[0029] Furthermore, the lubricating oil hole B6 connects the lubricating oil inlet B5 with the guide piston assembly 7 and the bearing bush 12 respectively, so that the lubricating oil can reach the guide piston assembly 7 and the bearing bush 12 to lubricate them;

[0030] The ammonia fuel hole M1, the ammonia fuel hole M2, and the ammonia fuel hole M3 constitute an ammonia fuel discharge flow channel V. When the pressure in the ammonia fuel volume chamber K1 is higher than the set opening pressure of the safety valve 4, the high-pressure ammonia fuel can be discharged through the ammonia fuel discharge flow channel V and finally flow into the ammonia fuel collection tank; wherein, the ammonia fuel in the ammonia fuel discharge flow channel V is designed with back pressure to prevent the ammonia fuel from vaporizing.

[0031] Furthermore, the common rail pump is a metering pump, and a pressure control valve 3 is installed on the pump cover assembly 2. The pressure control valve 3 controls the discharge flow of the high-pressure ammonia fuel pressurized by the common rail pump to adjust the rail pressure of each working condition, and the low-pressure ammonia fuel before entering the common rail pump needs to have a pressure of 3MPa to 10MPa and a temperature of -10°C to 30°C.

[0032] Furthermore, the common rail pump is designed with a flow channel for inert gas purging or diesel flushing. When the residual ammonia fuel in the common rail pump needs to be emptied, the pressure control valve 3 is adjusted to a fully open state, and an inert gas or diesel is introduced from the ammonia fuel inlet A1. A mixture of ammonia fuel and inert gas or a mixture of ammonia fuel and diesel will be discharged from the ammonia outlet connector 25, the ammonia fuel outlet L9, and the ammonia fuel reflux outlet K3, thereby achieving the removal of the residual ammonia fuel in the common rail pump.

[0033] The beneficial effects brought by the present invention are as follows:

[0034] It can be seen from the above scheme that the embodiment of the present invention provides a common rail pump for an ammonia fuel engine, including: a pump body assembly, a pump cover assembly, a pressure control valve, a safety valve, a plunger pair, an ammonia inlet and outlet valve assembly, a guide piston assembly and a camshaft. The pump cover assembly is installed on the upper part of the pump body assembly and is connected to the pump body assembly as a whole by bolts; the pressure control valve is fixed to the pump cover by screws; the safety valve is installed on the pump cover, and the plunger pair, the ammonia inlet and outlet valve assembly, the plunger spring, the plunger spring seat and the guide piston assembly are installed in the vertical middle hole of the pump body from top to bottom in sequence; the camshaft is installed in the horizontal middle hole of the pump body, and the camshaft is provided with a plurality of cams corresponding to the guide piston assemblies arranged in each vertical middle hole of the pump body. The technical scheme of the present invention can adapt to the characteristics of ammonia fuel, overcome technical difficulties such as gas-liquid phase change conversion, friction and wear, and safety design, meet the development needs of ammonia fuel engines, and has good safety, stability and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A first structural schematic diagram showing an ammonia fuel common rail pump according to an embodiment of the present invention;

[0036] Figure 2 This is a second structural schematic diagram of an ammonia fuel common rail pump according to an embodiment of the present invention;

[0037] Figure 3 A third structural schematic diagram of an ammonia fuel common rail pump according to an embodiment of the present invention;

[0038] Figure 4 This is a fourth structural schematic diagram of an ammonia fuel common rail pump according to an embodiment of the present invention;

[0039] Figure 5This is a schematic diagram of the structure of an ammonia inlet and outlet valve assembly according to an embodiment of the present invention;

[0040] Figure 6 A schematic diagram of the structure of a plunger pair according to an embodiment of the present invention;

[0041] Figure 7 This is a schematic diagram of the structure of a safety valve according to an embodiment of the present invention;

[0042] Figure 8 This is a schematic diagram of the structure of a pump cover assembly according to an embodiment of the present invention;

[0043] Fig. 9 This is a schematic diagram of the structure of a sliding valve pair according to an embodiment of the present invention;

[0044] Fig.10 This is a schematic diagram of the structure of a pressure control valve according to an embodiment of the present invention;

[0045] In the figure, 1-pump body assembly, 11-pump body, 12-bearing, 13-ammonia inlet joint, 14-oil inlet joint, 2-pump cover assembly, 21-pump cover, 22-first plug, 23-second plug, 24-third plug, 25-ammonia outlet joint, 26-abnormal leakage joint, 3-pressure control valve, 31-valve body, 32-sliding valve pair, 321-valve core, 322-valve sleeve, 33-spring, 34-spring seat, 35-adjusting screw, 36-nut, 37-proportional solenoid, 4-safety valve, 41-safety valve body, 42-safety valve core, 43-safety valve spring, 44-pressure regulating gasket, 45-safety valve joint, 5-plunger pair, 51-plunger sleeve, 52-plunger, 6-ammonia inlet and outlet valve assembly, 61- Ammonia inlet valve spring seat, 62-ammonia inlet valve spring, 63-ammonia inlet valve, 64-valve seat, 65-ammonia outlet valve, 66-ammonia outlet valve spring, 67-ammonia outlet valve spring seat, 7-guide piston assembly, 8-camshaft, A1-ammonia fuel inlet, A2-ammonia fuel hole, A3-sealing boss, A4-abnormal leakage fuel collection ring groove, B1-ammonia fuel hole, B2-ammonia fuel ring groove, B3-sealing oil hole, B4-air hole, B5-lubricating oil inlet, B6-lubricating oil hole, B7-abnormal leakage fuel collection groove, B8-abnormal leakage fuel collection hole, C1-ammonia fuel ring groove, C2-ammonia fuel ring groove, C3-ammonia fuel hole, C4-cavity for accommodating the ammonia outlet valve, C5-ammonia fuel hole, C6-ammonia fuel hole, C7-abnormal leakage fuel collection hole, C8-ammonia fuel return hole, D1-ammonia fuel hole, D2-cavity for accommodating ammonia inlet valve spring, E1-ammonia fuel hole, E2-cavity for accommodating ammonia outlet valve spring, F1-ammonia fuel hole, F2-cavity for accommodating ammonia outlet valve spring, G1-sealing oil ring groove, G2-sealing oil ring groove, G3-ammonia fuel ring groove, G4-sealing oil hole, G5-ammonia inlet hole, G6-ammonia fuel return hole, H1-micro ring groove, H2-plunger cavity, K1-ammonia fuel volume cavity, K2-ammonia fuel hole, K3-ammonia fuel return outlet, K4-ammonia fuel return hole, K5-sealing boss, K6-abnormal leakage fuel outlet, K7-abnormal leakage fuel collection hole, K8-abnormal leakage fuel collection hole, K9-abnormal leakage fuel collection hole, K10-abnormal leakage Leakage fuel collection hole, K11-abnormal leakage fuel collection hole, K12-abnormal leakage fuel collection hole, K13-abnormal leakage fuel collection hole, K14-abnormal leakage fuel collection hole, K15-pressure sensor interface, L1-abnormal leakage fuel collection ring groove, L2-sealing boss, L3-ammonia fuel volume cavity, L4-ammonia fuel hole, L5-flow control window, L6-ammonia fuel volume cavity, L7-ammonia fuel volume cavity, L8-ammonia fuel hole, L9-ammonia fuel outlet, L10-ammonia fuel hole, L11-leakage fuel collection cavity, L12-leakage fuel collection cavity, L13-leakage fuel outlet, L14-ammonia fuel hole, L15-ammonia fuel hole, M1-ammonia fuel hole, M2-ammonia fuel hole, M3-ammonia fuel hole. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] like Figures 1 to 10 As shown, Figure 1 This is a first structural schematic diagram of an ammonia fuel common rail pump according to an embodiment of the present invention. Figure 2 This is a second structural schematic diagram of an ammonia fuel common rail pump according to an embodiment of the present invention. Figure 3 is a third structural schematic diagram of an ammonia fuel common rail pump according to an embodiment of the present invention, Figure 4 is a fourth structural schematic diagram of an ammonia fuel common rail pump according to an embodiment of the present invention, Figure 5 This is a schematic diagram of the structure of an ammonia inlet and outlet valve assembly according to an embodiment of the present invention. Figure 6 Schematic diagram of the structure of a plunger pair according to an embodiment of the present invention. Figure 7 Schematic diagram of a safety valve structure according to an embodiment of the present invention. Figure 8 Schematic diagram of the structure of a pump cover assembly according to an embodiment of the present invention. Fig. 9 Schematic diagram of the structure of a sliding valve pair according to an embodiment of the present invention. Fig.10 The figure is a schematic diagram of the structure of a pressure control valve according to an embodiment of the present invention.

[0048] Figure 1 In the invention, a common rail pump for an ammonia fuel engine includes: a pump body assembly 1, a pump cover assembly 2, a pressure control valve 3, a safety valve 4, a plunger pair 5, an ammonia inlet and outlet valve assembly 6, a guide piston assembly 7 and a camshaft 8.

[0049] The pump body group 1 includes: a pump body 11 with a horizontal center hole and a plurality of vertical center holes connected to the horizontal center hole, a bearing 12 installed in the horizontal center hole of the pump body 11, an ammonia inlet connector 13 fixedly connected to the pump body 11 by screws, and an oil inlet connector 14 installed on the pump body 11.

[0050] The pump cover assembly 2 is installed on the upper part of the pump body assembly 1 and connected to the pump body assembly 1 as a whole by bolts; the pump cover assembly 2 includes: a pump cover 21, a first plug 22, a second plug 23, a third plug 24, an ammonia outlet joint 25 and an abnormal leakage joint 26;

[0051] The pressure control valve 3 comprises: a valve body 31 , a sliding valve pair 32 , a spring 33 , a spring seat 34 , an adjusting screw 35 , a nut 36 and a proportional solenoid 37 , which is fixed to the pump cover 21 by screws; the sliding valve pair 32 comprises a valve core 321 and a valve sleeve 322 .

[0052] The safety valve 4 is installed on the pump cover 21, and includes: a safety valve body 41, a safety valve core 42, a safety valve spring 43, a pressure regulating gasket 44 and a safety valve connector 45;

[0053] The plunger pair 5, the ammonia inlet and outlet valve assembly 6, the plunger spring, the plunger spring seat and the guide piston assembly 7 are installed in the vertical middle hole of the pump body 11 from top to bottom in sequence; the plunger pair 5 includes: a plunger sleeve 51 and a plunger 52 in the plunger sleeve 51; the ammonia inlet and outlet valve assembly 6 includes: an ammonia inlet valve spring seat 61, an ammonia inlet valve spring 62, an ammonia inlet valve 63, a valve seat 64, an ammonia outlet valve 65, an ammonia outlet valve spring 66, and an ammonia outlet valve spring seat 67;

[0054] The camshaft 8 is installed in the horizontal center hole of the pump body 11, and the camshaft 8 is provided with a plurality of cams corresponding to the guide piston assemblies 7 provided in the vertical center holes of the pump body 11;

[0055] The plunger pair 5, the inlet and outlet ammonia valve assembly 6 and the pump cover assembly 2 are connected as a whole by bolts; the plunger pair 5 and the inlet and outlet ammonia valve assembly 6, and the inlet and outlet ammonia valve assembly 6 and the pump cover assembly 2 are positioned by positioning pins.

[0056] Figure 2 In the invention, the common rail pump comprises:

[0057] The ammonia inlet joint 13 is designed with an ammonia fuel inlet A1, an ammonia fuel hole A2, a sealing boss A3 and an abnormal leakage fuel collection annular groove A4; the pump body 11 is designed with an ammonia fuel hole B1, and each vertical center hole of the pump body 11 is designed with an ammonia fuel annular groove B2 connected to the ammonia fuel hole B1, the pump body 11 is designed with a sealing oil hole B3 connected to the oil inlet joint 14, the pump body 11 is designed with an air hole B4 to connect multiple vertical center holes inside the pump body 11, the pump body 11 is designed with a lubricating oil inlet B5 and a lubricating oil hole B6, the upper end surface of the pump body 11 is designed with an abnormal leakage fuel collection groove B7, and the pump body 11 is designed with an abnormal leakage fuel collection hole B8 connecting the abnormal leakage fuel collection annular groove A4 and the abnormal leakage fuel collection groove B7;

[0058] Figure 3 and Figure 5In the figure, the outer circle of the valve seat 64 is designed with an ammonia fuel ring groove C1, the end of the valve seat 64 that contacts the plunger pair 5 is designed with an ammonia fuel ring groove C2, the valve seat 64 is designed with multiple ammonia fuel holes C3 connecting the ammonia fuel ring groove C1 and the ammonia fuel ring groove C2, the valve seat 64 is designed with a cavity C4 for accommodating the ammonia outlet valve 65, the valve seat 64 is designed with an ammonia fuel hole C5 connected to the cavity C4, the valve seat 64 is designed with an ammonia fuel hole C6, an abnormal leakage fuel collection hole C7, and an ammonia fuel reflux hole C8, and the abnormal leakage fuel collection hole C7 is connected to the abnormal leakage fuel collection groove B7; the ammonia inlet valve 63 is designed with an ammonia fuel hole D1 and a cavity D2 for accommodating the ammonia inlet valve spring 62; the ammonia outlet valve 65 is designed with an ammonia fuel hole E1 and a cavity E2 for accommodating the ammonia outlet valve spring 66; the ammonia outlet valve spring seat 67 is designed with an ammonia fuel hole F1 and a cavity F2 for accommodating the ammonia outlet valve spring 66.

[0059] Figure 1 , Figure 3 and Figure 6 In the embodiment, a sealing oil ring groove G1 is designed on the outer circle of the plunger sleeve 51, a sealing oil ring groove G2 and an ammonia fuel ring groove G3 are designed in the middle hole of the plunger sleeve 51, a sealing oil hole G4 is designed on the plunger sleeve 51 to connect the sealing oil ring groove G1 and the sealing oil ring groove G2, an ammonia inlet hole G5 is designed on the plunger sleeve 51 to connect the ammonia fuel hole C6 and the ammonia fuel ring groove G3, and an ammonia fuel return hole G6 is designed on the plunger sleeve 51 to connect the ammonia fuel return hole C8 and the ammonia fuel ring groove G3; a plurality of tiny ring grooves H1 are designed on the outer circle of the plunger 52, and a coating with good self-lubricating property is plated on the outer circle surface of the plunger 52, and the plunger sleeve 51, the plunger 52 and the ammonia outlet valve 65 cooperate to form a plunger cavity H2;

[0060] Figure 1 , Figure 2 , Figure 3 and Figure 8The pump cover 21 is designed with an ammonia fuel volume cavity K1, the pump cover 21 is designed with an ammonia fuel hole K2 connecting the ammonia fuel hole F1 and the ammonia fuel volume cavity K1, the pump cover 21 is designed with an ammonia fuel reflux outlet K3, the pump cover 21 is designed with an ammonia fuel reflux hole K4 connecting the ammonia fuel reflux hole C8 and the ammonia fuel reflux outlet K3, the pump cover 21 is designed with a sealing boss K5, the pump cover 21 is designed with an abnormal leakage fuel outlet K6, the pump cover 21 is designed with an abnormal leakage fuel collection hole K7 connecting the abnormal leakage collection ring groove L1 and the abnormal leakage fuel outlet K6, the pump cover 21 is designed with an abnormal leakage fuel collection hole K8 connecting the abnormal leakage fuel collection ring groove L1 and the abnormal leakage fuel outlet K6, and the pump cover 21 is designed with an abnormal leakage fuel collection hole K8 connecting the abnormal leakage fuel collection ring groove L1 and the abnormal leakage fuel outlet K6. The normally leaking fuel collecting groove B7 and the abnormal leaking fuel outlet K6, the pump cover 21 is designed with an abnormal leaking fuel collecting hole K9, and the ammonia fuel leaking from the sealing surface between the ammonia outlet connector 25 and the pump cover 21 is introduced into the abnormal leaking fuel collecting groove B7, the pump cover 21 is designed with abnormal leaking fuel collecting hole K10, abnormal leaking fuel collecting hole K11, abnormal leaking fuel collecting hole K12, abnormal leaking fuel collecting hole K13, abnormal leaking fuel collecting hole K14, the pump cover 21 is designed with a pressure sensor interface K15, if it is necessary to monitor the pressure in the ammonia fuel volume cavity of the pump cover, remove the plug 22 and replace it with a pressure sensor.

[0061] Figure 2 , Figure 4 , Fig.10 In the embodiment, the pressure control valve 3 is designed with an abnormal leakage fuel collection annular groove L1, a sealing boss L2, and an ammonia fuel volume chamber L3. The pressure control valve 3 is designed with an ammonia fuel hole L4 connecting the ammonia fuel volume chamber L3 and the ammonia fuel volume chamber K1. The pressure control valve 3 is designed with a flow control window L5, an ammonia fuel volume chamber L6, and an ammonia fuel volume chamber L7. The pressure control valve 3 is designed with an ammonia fuel hole L8 connecting the ammonia fuel volume chamber L6 and the ammonia fuel volume chamber L7. The pressure control valve 3 is designed with an ammonia fuel outlet L 9, an ammonia fuel hole L10 is designed to connect the ammonia fuel volume chamber L7 and the ammonia fuel outlet L9, the pressure control valve 3 is designed with a leakage fuel collecting chamber L11, a leakage fuel collecting chamber L12, and a leakage fuel outlet L13, the pressure control valve 3 is designed with an ammonia fuel hole L14 to connect the leakage fuel collecting chamber L11 and the leakage fuel collecting chamber L12, and an ammonia fuel hole L15 to connect the leakage fuel collecting chamber L12 and the leakage fuel outlet L13, and the proportional solenoid 37 adopts an explosion-proof design;.

[0062] Figure 7 In the embodiment, the safety valve body 41 is designed with an ammonia fuel hole M1; the safety valve core 42 is designed with an ammonia fuel hole M2; and the safety valve connector 45 is designed with an ammonia fuel hole M3.

[0063] In another embodiment of the present invention, the ammonia fuel inlet A1, the ammonia fuel hole A2, the ammonia fuel hole B1, the ammonia fuel annular groove B2, the ammonia fuel annular groove C1, the ammonia fuel hole C3 and the ammonia fuel annular groove C2 constitute a low-pressure ammonia fuel supply flow channel N, and the low-pressure ammonia fuel reaches the ammonia fuel annular groove C2 from the ammonia fuel inlet A1 through the low-pressure ammonia fuel supply flow channel N, and then enters the plunger cavity H2 through the ammonia inlet valve 63;

[0064] The ammonia fuel hole C6, the ammonia inlet hole G5, the ammonia fuel ring groove G3, the ammonia fuel reflux hole G6, the ammonia fuel reflux hole C8, the ammonia fuel reflux hole K4 and the ammonia fuel reflux outlet K3 constitute a low-pressure ammonia fuel reflux flow channel P. The low-pressure ammonia fuel in the channel formed by the ammonia fuel ring groove B2 and the ammonia fuel ring groove C1 enters the ammonia fuel ring groove G3 through the ammonia fuel hole C6 and the ammonia inlet hole G5, merges with the ammonia fuel leaking from the plunger cavity H2 through the gap of the plunger couple 5 to the ammonia fuel ring groove G3, and finally enters the ammonia fuel tank through the ammonia fuel reflux hole G6, the ammonia fuel reflux hole C8, the ammonia fuel reflux hole K4 and the ammonia fuel reflux outlet K3.

[0065] In yet another embodiment of the present invention, Figure 1 , Figure 4 , Figure 5 , Figure 8 , Fig.10 In the embodiment, the ammonia fuel hole D1, the ammonia fuel hole C5, the ammonia fuel hole E1, the ammonia fuel hole F1, the ammonia fuel hole K2 and the ammonia fuel volume cavity K1 constitute a high-pressure ammonia fuel flow channel Q. After the ammonia fuel is pressurized by the plunger 52, it enters the ammonia fuel volume cavity K1 through the high-pressure ammonia fuel flow channel Q; the high-pressure ammonia fuel in the ammonia fuel volume cavity K1 is delivered to the common rail pipe through the ammonia outlet joint 25 on the one hand, and on the other hand, it passes through the ammonia fuel discharge flow channel R composed of the ammonia fuel hole L4, the ammonia fuel volume cavity L3, the flow control window L5, the ammonia fuel volume cavity L6, the ammonia fuel hole L8, the ammonia fuel volume cavity L7, the ammonia fuel hole L10 and the ammonia fuel outlet L9, and finally flows back to the ammonia fuel collection tank, and the discharge ammonia fuel flow is adjusted by the pressure control valve 3;

[0066] The leakage fuel collection chamber L11, the ammonia fuel hole L14, the leakage fuel collection chamber L12, the ammonia fuel hole L15 and the leakage fuel outlet L13 constitute an ammonia fuel leakage collection flow channel S, which collects the ammonia fuel leaking from the gap of the sliding valve pair 32. The ammonia fuel in the ammonia fuel leakage collection flow channel S is designed with back pressure to ensure that the liquid ammonia does not vaporize.

[0067] In another embodiment of the present invention, the oil inlet connector 14, the sealing oil hole B3, the sealing oil ring groove G1, the sealing oil hole G4 and the sealing oil ring groove G2 form a sealing oil passage T for introducing the sealing oil into the sealing oil ring groove G2, and the sealing oil pressure is greater than the low-pressure ammonia fuel pressure at the inlet of the common rail pump to prevent leakage of the ammonia fuel. At the same time, the sealing oil also plays a lubricating role on the plunger pair (5).

[0068] In another embodiment of the present invention, the abnormal leakage fuel collecting hole C7, the abnormal leakage fuel collecting hole B8, the abnormal leakage fuel collecting groove B7, the abnormal leakage fuel collecting hole K7, the abnormal leakage fuel collecting hole K8, the abnormal leakage fuel collecting hole K9, the abnormal leakage fuel collecting hole K10, the abnormal leakage fuel collecting hole K11, the abnormal leakage fuel collecting hole K12, the abnormal leakage fuel collecting hole K13, the abnormal leakage fuel collecting hole K14 and the abnormal leakage fuel outlet K6 constitute the abnormal leakage fuel collecting channel U, the fuel abnormally leaked inside the common rail pump is discharged from the abnormal leakage fuel outlet K6 and finally flows into the ammonia fuel collection tank.

[0069] In another embodiment of the present invention, the common rail pump adopts a two-seal design to prevent leakage of ammonia fuel, and an abnormal leakage fuel collection flow channel U is designed between the first seal and the second seal. If the first seal fails, the leaked ammonia fuel is discharged to the ammonia fuel collection tank through the abnormal leakage fuel collection flow channel U; the inner side of the abnormal leakage fuel collection annular groove A4 is a first seal composed of the sealing boss A3 and the sealing plane of the pump body 11, and a sealing ring is arranged on the outer side as a second seal; the inner side of the leakage fuel collection annular groove L1 is a first seal composed of the sealing boss L2 and the sealing boss K5, and a sealing ring is arranged on the outer side as a second seal;

[0070] The first plug 22, the second plug 23 and the third plug 24 are all provided with sealing rings as the second seal, and the sealing cone surface of the steel ball and the pump cover 21 constitute the first seal; the sealing spherical surface of the safety valve 4 and the sealing cone surface of the pump cover 21 constitute the first seal, and a sealing ring is provided between the safety valve 4 and the pump cover 21 as the second seal; a sealing ring is designed on the outer circle of the valve seat 64 as the first seal, and a sealing ring is designed on the upper end surface of the pump body 11 as the second seal; a sealing ring is provided in the gap between the plunger and the pair 5 as the second seal, and the sealing oil in the gap between the pair serves as the first seal.

[0071] In another embodiment of the present invention, the lubricating oil hole B6 connects the lubricating oil inlet B5 with the guide piston assembly 7 and the bearing bush 12 respectively, so that the lubricating oil can reach the guide piston assembly 7 and the bearing bush 12 to lubricate them;

[0072] The ammonia fuel hole M1, the ammonia fuel hole M2, and the ammonia fuel hole M3 constitute an ammonia fuel discharge flow channel V. When the pressure in the ammonia fuel volume chamber K1 is higher than the set opening pressure of the safety valve 4, the high-pressure ammonia fuel can be discharged through the ammonia fuel discharge flow channel V and finally flow into the ammonia fuel collection tank; wherein, the ammonia fuel in the ammonia fuel discharge flow channel V is designed with back pressure to prevent the ammonia fuel from vaporizing.

[0073] In another embodiment of the present invention, the common rail pump is a metering pump, and a pressure control valve 3 is installed on the pump cover assembly 2. The pressure control valve 3 controls the discharge flow rate of the high-pressure ammonia fuel pressurized by the common rail pump to adjust the rail pressure of each working condition, and the low-pressure ammonia fuel before entering the common rail pump needs to have a pressure of 3MPa to 10MPa and a temperature of -10°C to 30°C.

[0074] In another embodiment of the present invention, the common rail pump is designed with a flow channel for inert gas purging or diesel flushing. When it is necessary to clear the residual ammonia fuel in the common rail pump, the pressure control valve 3 is adjusted to a fully open state, and an inert gas or diesel is introduced from the ammonia fuel inlet A1. A mixture of ammonia fuel and inert gas or a mixture of ammonia fuel and diesel will be discharged from the ammonia outlet connector 25, the ammonia fuel outlet L9, and the ammonia fuel reflux outlet K3, thereby achieving the removal of the residual ammonia fuel in the common rail pump.

[0075] In the embodiment of the present invention, the common rail pump is designed as a metering pump. The pressure control valve controls the discharge flow of the high-pressure ammonia fuel after pressurization by the common rail pump to adjust the rail pressure of each working condition. There is no proportional valve to control the flow of the low-pressure ammonia fuel entering the common rail pump. At the same time, the pressure of the low-pressure ammonia fuel before entering the common rail pump is 3MPa~10MPa, and the temperature is -10℃~30℃, thereby ensuring that the ammonia fuel always remains in a liquid state and avoiding problems such as cavitation and air resistance. A low-pressure ammonia fuel reflux flow channel is designed. After the low-pressure ammonia fuel enters the common rail pump, in addition to the pressurized part of the ammonia fuel entering the plunger cavity, the remaining ammonia fuel will return to the ammonia fuel tank through the low-pressure ammonia fuel reflux flow channel. The low-pressure ammonia fuel forms a circulation loop, which can take away the heat generated by the operation of the plunger pair and improve the reliability of the plunger pair. The sealing oil flow channel is designed to seal the ammonia fuel in the plunger pair to prevent the ammonia fuel from leaking from the gap between the pairs. At the same time, the sealing oil also lubricates the plunger pair.

[0076] In the embodiment of the present invention, an abnormal leakage fuel collection flow channel is designed. If there is a seal failure in the common rail pump, the leaked ammonia fuel will be discharged from the abnormal leakage fuel collection flow channel and eventually enter the ammonia fuel collection tank. The sealing of the ammonia fuel in the common rail pump adopts a two-seal design. An abnormal leakage fuel collection flow channel is designed between the first seal and the second seal. If the first seal fails, the leaked ammonia fuel will be discharged to the ammonia fuel collection tank through the abnormal leakage fuel collection flow channel. At the same time, the second seal can ensure that the ammonia fuel in the abnormal leakage fuel collection flow channel does not leak. Sealing oil is used as the first seal in the gap between the plunger and the pair, and the sealing ring is used as the second seal. The safety valve is designed with back pressure. When the safety valve is opened, it ensures that the high-pressure ammonia fuel in the pump cover does not vaporize after flowing out of the pump cover, and keeps flowing into the ammonia fuel collection tank in liquid form. The ammonia fuel outlet and the leakage fuel outlet on the pressure control valve are also designed with back pressure, which can ensure that the ammonia fuel does not vaporize and keeps flowing into the ammonia fuel collection tank in liquid form.

[0077] The common rail pump is designed with inert gas purging or diesel flushing functions. Adjust the pressure control valve to the fully open state, and then introduce inert gas or diesel from the same inlet as the low-pressure ammonia fuel. The mixture of ammonia fuel and inert gas or ammonia fuel and diesel will be discharged from the ammonia outlet joint, the ammonia fuel outlet on the pressure control valve, and the ammonia fuel reflux outlet on the pump cover, which can achieve the removal of residual ammonia fuel in the common rail pump. The common rail pump abnormal leakage fuel collection flow channel is separated from the ammonia fuel leakage collection flow channel in the pressure control valve. An independent design is adopted, and the two flow channels are not connected to each other. Because under normal circumstances, there is no ammonia fuel in the abnormal leakage fuel collection flow channel. Only when the seal fails will there be ammonia fuel, and there will always be a small amount of ammonia fuel leaking from the gap between the sliding valve pair in the pressure control valve. Separating the two flow channels is convenient for judging whether the seal of the common rail pump has failed. The plunger is plated with a coating DLC ​​with good self-lubricating properties, and multiple micro-ring grooves are designed on the outer circle of the plunger, which is conducive to improving the reliability of the plunger pair. The pressure control valve is designed as a normally closed valve, which can drive the valve core to move through the proportional solenoid to adjust the opening of the flow control window, thereby controlling the flow of high-pressure ammonia fuel, and finally achieving the regulation of rail pressure. The pump cover is equipped with a pressure sensor interface. By removing the plug and replacing it with a pressure sensor, the pressure in the ammonia fuel volume chamber of the pump cover can be monitored.

[0078] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An ammonia fuel engine common rail pump, characterized in that: The common rail pump comprises: a pump body assembly (1), a pump cover assembly (2), a pressure control valve (3), a safety valve (4), a plunger pair (5), an ammonia inlet and outlet valve assembly (6), a guide piston assembly (7) and a camshaft (8); The pump body assembly (1) comprises: a pump body (11) having a horizontal center hole and a plurality of vertical center holes connected to the horizontal center hole, a bearing bush (12) installed in the horizontal center hole of the pump body (11), an ammonia inlet joint (13) fixedly connected to the pump body (11) by screws, and an oil inlet joint (14) installed on the pump body (11); The pump cover assembly (2) is mounted on the upper part of the pump body assembly (1) and connected to the pump body assembly (1) as a whole by bolts; the pump cover assembly (2) comprises: a pump cover (21), a first plug (22), a second plug (23), a third plug (24), an ammonia outlet joint (25) and an abnormal leakage joint (26); The pressure control valve (3) comprises: a valve body (31), a sliding valve pair (32), a spring (33), a spring seat (34), an adjusting screw (35), a nut (36) and a proportional electromagnet (37), which are fixed to the pump cover (21) by screws; the sliding valve pair (32) comprises a valve core (321) and a valve sleeve (322); The safety valve (4) is installed on the pump cover (21), and comprises: a safety valve body (41), a safety valve core (42), a safety valve spring (43), a pressure regulating gasket (44) and a safety valve connector (45); The plunger pair (5), the ammonia inlet and outlet valve assembly (6), the plunger spring, the plunger spring seat and the guide piston assembly (7) are installed in the vertical center hole of the pump body (11) from top to bottom in sequence; the plunger pair (5) comprises: a plunger sleeve (51) and a plunger (52) in the plunger sleeve (51); the ammonia inlet and outlet valve assembly (6) comprises: an ammonia inlet valve spring seat (61), an ammonia inlet valve spring (62), an ammonia inlet valve (63), a valve seat (64), an ammonia outlet valve (65), an ammonia outlet valve spring (66) and an ammonia outlet valve spring seat (67); The camshaft (8) is installed in the horizontal center hole of the pump body (11), and the camshaft (8) is provided with a plurality of cams respectively corresponding to the guide piston assemblies (7) arranged in the vertical center holes of the pump body (11); The plunger pair (5), the inlet and outlet ammonia valve assembly (6) and the pump cover assembly (2) are connected as a whole by bolts; the plunger pair (5) and the inlet and outlet ammonia valve assembly (6), and the inlet and outlet ammonia valve assembly (6) and the pump cover assembly (2) are positioned by positioning pins.

2. The ammonia fuel engine common rail pump according to claim 1, characterized in that: The common rail pump comprises: The ammonia inlet joint (13) is designed with an ammonia fuel inlet A1, an ammonia fuel hole A2, a sealing boss A3 and an abnormal leakage fuel collection annular groove A4; the pump body (11) is designed with an ammonia fuel hole B1, and each vertical center hole of the pump body (11) is designed with an ammonia fuel annular groove B2 connected to the ammonia fuel hole B1; the pump body (11) is designed with a sealing oil hole B3 connected to the oil inlet joint (14); the pump body (11) is designed with an air hole B4 connecting multiple vertical center holes inside the pump body (11); the pump body (11) is designed with a lubricating oil inlet B5 and a lubricating oil hole B6; the upper end surface of the pump body (11) is designed with an abnormal leakage fuel collection groove B7; the pump body (11) is designed with an abnormal leakage fuel collection hole B8 connected to the abnormal leakage fuel collection annular groove A4 and the abnormal leakage fuel collection groove B7; The outer circle of the valve seat (64) is designed with an ammonia fuel annular groove C1, the end of the valve seat (64) in contact with the plunger pair (5) is designed with an ammonia fuel annular groove C2, the valve seat (64) is designed with a plurality of ammonia fuel holes C3 connecting the ammonia fuel annular groove C1 and the ammonia fuel annular groove C2, the valve seat (64) is designed with a cavity C4 for accommodating the ammonia outlet valve (65), the valve seat (64) is designed with an ammonia fuel hole C5 connected to the cavity C4, and the valve seat (64) is designed with an ammonia fuel hole C6. , an abnormal leakage fuel collection hole C7, an ammonia fuel reflux hole C8, the abnormal leakage fuel collection hole C7 is connected to the abnormal leakage fuel collection groove B7; the ammonia inlet valve (63) is designed with an ammonia fuel hole D1 and a cavity D2 for accommodating the ammonia inlet valve spring (62); the ammonia outlet valve (65) is designed with an ammonia fuel hole E1 and a cavity E2 for accommodating the ammonia outlet valve spring (66); the ammonia outlet valve spring seat (67) is designed with an ammonia fuel hole F1 and a cavity F2 for accommodating the ammonia outlet valve spring (66); The plunger sleeve (51) is provided with a sealing oil ring groove G1 on its outer circumference, a sealing oil ring groove G2 and an ammonia fuel ring groove G3 are provided in the middle hole of the plunger sleeve (51), the plunger sleeve (51) is provided with a sealing oil hole G4 connecting the sealing oil ring groove G1 and the sealing oil ring groove G2, the plunger sleeve (51) is provided with an ammonia inlet hole G5 connecting the ammonia fuel hole C6 and the ammonia fuel ring groove G3, and the plunger sleeve (51) is provided with an ammonia fuel return hole G6 connecting the ammonia fuel return hole C8 and the ammonia fuel ring groove G3; a plurality of tiny ring grooves H1 are provided on the outer circumference of the plunger (52), the outer circumferential surface of the plunger (52) is plated with a coating with good self-lubricating properties, and the plunger sleeve (51), the plunger (52) and the ammonia outlet valve (65) cooperate to form a plunger cavity H2; The pump cover (21) is designed with an ammonia fuel volume cavity K1, the pump cover (21) is designed with an ammonia fuel hole K2 connecting the ammonia fuel hole F1 and the ammonia fuel volume cavity K1, the pump cover (21) is designed with an ammonia fuel reflux outlet K3, the pump cover (21) is designed with an ammonia fuel reflux hole K4 connecting the ammonia fuel reflux hole C8 and the ammonia fuel reflux outlet K3, the pump cover (21) is designed with a sealing boss K5, the pump cover (21) is designed with an abnormal leakage fuel outlet K6, the pump cover (21) is designed with an abnormal leakage fuel collection hole K7 connecting the abnormal leakage collection ring groove L1 and the abnormal leakage fuel outlet K6, the pump cover (21) is designed with an abnormal leakage fuel collection hole K8 connecting The abnormal leakage fuel collection groove B7 and the abnormal leakage fuel outlet K6 are connected, and the pump cover (21) is designed with an abnormal leakage fuel collection hole K9, and the ammonia fuel leaking from the sealing surface between the ammonia outlet joint (25) and the pump cover (21) is introduced into the abnormal leakage fuel collection groove B7. The pump cover (21) is designed with abnormal leakage fuel collection holes K10, abnormal leakage fuel collection holes K11, abnormal leakage fuel collection holes K12, abnormal leakage fuel collection holes K13, and abnormal leakage fuel collection holes K14. The pump cover (21) is designed with a pressure sensor interface K15. If it is necessary to monitor the pressure in the ammonia fuel volume cavity of the pump cover, the plug (22) is removed and replaced with a pressure sensor; The pressure control valve (3) is designed with an abnormal leakage fuel collection annular groove L1, a sealing boss L2, and an ammonia fuel volume chamber L3. The pressure control valve (3) is designed with an ammonia fuel hole L4 connecting the ammonia fuel volume chamber L3 and the ammonia fuel volume chamber K1. The pressure control valve (3) is designed with a flow control window L5, an ammonia fuel volume chamber L6, and an ammonia fuel volume chamber L7. The pressure control valve (3) is designed with an ammonia fuel hole L8 connecting the ammonia fuel volume chamber L6 and the ammonia fuel volume chamber L7. The pressure control valve (3) is designed with an ammonia fuel The outlet L9 is designed with an ammonia fuel hole L10 connecting the ammonia fuel volume chamber L7 and the ammonia fuel outlet L9, the pressure control valve (3) is designed with a leakage fuel collection chamber L11, a leakage fuel collection chamber L12, and a leakage fuel outlet L13, the pressure control valve (3) is designed with an ammonia fuel hole L14 connecting the leakage fuel collection chamber L11 and the leakage fuel collection chamber L12, and is designed with an ammonia fuel hole L15 connecting the leakage fuel collection chamber L12 and the leakage fuel outlet L13, and the proportional solenoid (37) adopts an explosion-proof design; The safety valve body (41) is designed with an ammonia fuel hole M1; the safety valve core (42) is designed with an ammonia fuel hole M2; and the safety valve connector (45) is designed with an ammonia fuel hole M3.

3. The ammonia fuel engine common rail pump according to claim 2, characterized in that: The ammonia fuel inlet A1, the ammonia fuel hole A2, the ammonia fuel hole B1, the ammonia fuel annular groove B2, the ammonia fuel annular groove C1, the ammonia fuel hole C3 and the ammonia fuel annular groove C2 form a low-pressure ammonia fuel supply flow channel N. The low-pressure ammonia fuel flows from the ammonia fuel inlet A1 through the low-pressure ammonia fuel supply flow channel N to the ammonia fuel annular groove C2, and then enters the plunger cavity H2 through the ammonia inlet valve (63); The ammonia fuel hole C6, the ammonia inlet hole G5, the ammonia fuel ring groove G3, the ammonia fuel reflux hole G6, the ammonia fuel reflux hole C8, the ammonia fuel reflux hole K4 and the ammonia fuel reflux outlet K3 constitute a low-pressure ammonia fuel reflux flow channel P. The low-pressure ammonia fuel in the channel formed by the ammonia fuel ring groove B2 and the ammonia fuel ring groove C1 enters the ammonia fuel ring groove G3 through the ammonia fuel hole C6 and the ammonia inlet hole G5, merges with the ammonia fuel leaking from the plunger cavity H2 through the gap of the plunger couple (5) to the ammonia fuel ring groove G3, and finally enters the ammonia fuel tank through the ammonia fuel reflux hole G6, the ammonia fuel reflux hole C8, the ammonia fuel reflux hole K4 and the ammonia fuel reflux outlet K3.

4. The ammonia fuel engine common rail pump according to claim 2, characterized in that: The ammonia fuel hole D1, the ammonia fuel hole C5, the ammonia fuel hole E1, the ammonia fuel hole F1, the ammonia fuel hole K2 and the ammonia fuel volume cavity K1 form a high-pressure ammonia fuel flow channel Q. After the ammonia fuel is pressurized by the plunger (52), it enters the ammonia fuel volume cavity K1 through the high-pressure ammonia fuel flow channel Q; the high-pressure ammonia fuel in the ammonia fuel volume cavity K1 is delivered to the common rail pipe through the ammonia outlet joint (25) on the one hand, and on the other hand, it passes through the ammonia fuel discharge flow channel R composed of the ammonia fuel hole L4, the ammonia fuel volume cavity L3, the flow control window L5, the ammonia fuel volume cavity L6, the ammonia fuel hole L8, the ammonia fuel volume cavity L7, the ammonia fuel hole L10 and the ammonia fuel outlet L9, and finally flows back to the ammonia fuel collection tank, and the discharge ammonia fuel flow rate is adjusted by the pressure control valve (3); The leakage fuel collection chamber L11, the ammonia fuel hole L14, the leakage fuel collection chamber L12, the ammonia fuel hole L15 and the leakage fuel outlet L13 constitute an ammonia fuel leakage collection flow channel S, which collects the ammonia fuel leaking from the gap of the sliding valve pair (32). The ammonia fuel in the ammonia fuel leakage collection flow channel S is designed with back pressure to ensure that the liquid ammonia does not vaporize.

5. The ammonia fuel engine common rail pump according to claim 1, characterized in that: The oil inlet joint (14), the sealing oil hole B3, the sealing oil ring groove G1, the sealing oil hole G4 and the sealing oil ring groove G2 form a sealing oil passage T for introducing sealing oil into the sealing oil ring groove G2, and the sealing oil pressure is greater than the low-pressure ammonia fuel pressure at the inlet of the common rail pump, thereby preventing leakage of ammonia fuel.

6. The ammonia fuel engine common rail pump according to claim 2, characterized in that: The abnormal leakage fuel collecting hole C7, the abnormal leakage fuel collecting hole B8, the abnormal leakage fuel collecting groove B7, the abnormal leakage fuel collecting hole K7, the abnormal leakage fuel collecting hole K8, the abnormal leakage fuel collecting hole K9, the abnormal leakage fuel collecting hole K10, the abnormal leakage fuel collecting hole K11, the abnormal leakage fuel collecting hole K12, the abnormal leakage fuel collecting hole K13, the abnormal leakage fuel collecting hole K14 and the abnormal leakage fuel outlet K6 constitute the abnormal leakage fuel collecting channel U, and the fuel abnormally leaked inside the common rail pump is discharged from the abnormal leakage fuel outlet K6 and finally flows into the ammonia fuel collection tank.

7. The ammonia fuel engine common rail pump according to claim 2, characterized in that: The common rail pump adopts a two-seal design to prevent ammonia fuel leakage. An abnormal leakage fuel collection flow channel U is designed between the first seal and the second seal. If the first seal fails, the leaked ammonia fuel is discharged to the ammonia fuel collection tank through the abnormal leakage fuel collection flow channel U; the inner side of the abnormal leakage fuel collection annular groove A4 is a first seal formed by the sealing boss A3 and the sealing plane of the pump body 11, and a sealing ring is arranged on the outer side as a second seal; the inner side of the leakage fuel collection annular groove L1 is a first seal formed by the sealing boss L2 and the sealing boss K5, and a sealing ring is arranged on the outer side as a second seal; The first plug (22), the second plug (23) and the third plug (24) are all provided with sealing rings as the second seal, and the steel ball and the sealing cone surface of the pump cover (21) constitute the first seal; the sealing spherical surface of the safety valve (4) and the sealing cone surface of the pump cover (21) constitute the first seal, and a sealing ring is provided between the safety valve (4) and the pump cover (21) as the second seal; a sealing ring is designed on the outer circle of the valve seat (64) as the first seal, and a sealing ring is designed on the upper end surface of the pump body (11) as the second seal; a sealing ring is provided in the gap between the plunger and the piston pair (5) as the second seal, and the sealing oil in the gap between the pair serves as the first seal.

8. The ammonia fuel engine common rail pump according to claim 2, characterized in that: The lubricating oil hole B6 connects the lubricating oil inlet B5 to the guide piston assembly (7) and the bearing bush (12) respectively, so that the lubricating oil can reach the guide piston assembly (7) and the bearing bush (12) to lubricate them; The ammonia fuel hole M1, the ammonia fuel hole M2, and the ammonia fuel hole M3 form an ammonia fuel discharge flow channel V. When the pressure in the ammonia fuel volume chamber K1 is higher than the set opening pressure of the safety valve (4), the high-pressure ammonia fuel can be discharged through the ammonia fuel discharge flow channel V and finally flow into the ammonia fuel collection tank; wherein, the ammonia fuel in the ammonia fuel discharge flow channel V is designed with back pressure to prevent the ammonia fuel from vaporizing.

9. The ammonia fuel engine common rail pump according to claim 1, characterized in that: The common rail pump is a metering pump. The pressure control valve (3) is installed on the pump cover assembly (2). The pressure control valve (3) controls the discharge flow of the high-pressure ammonia fuel pressurized by the common rail pump to adjust the rail pressure of each working condition. The low-pressure ammonia fuel before entering the common rail pump needs to have a pressure of 3MPa to 10MPa and a temperature of -10°C to 30°C.

10. The ammonia fuel engine common rail pump according to claim 1, characterized in that: The common rail pump is designed with a flow channel for inert gas purging or diesel flushing. When it is necessary to clear the residual ammonia fuel in the common rail pump, the pressure control valve (3) is adjusted to a fully open state, and inert gas or diesel is introduced from the ammonia fuel inlet A1. A mixture of ammonia fuel and inert gas or a mixture of ammonia fuel and diesel is discharged from the ammonia outlet connector (25), the ammonia fuel outlet L9, and the ammonia fuel reflux outlet K3, thereby clearing the residual ammonia fuel in the common rail pump.

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