An electronically controlled common rail fuel injection system with a single solenoid valve

Abstract

The present invention relates to the technical field of engine fuel injection systems, and specifically to an electronically controlled common rail fuel injection system with a single solenoid valve, comprising a high-pressure fuel supply pump, a fuel separator component, a fuel tank, a mechanical fuel injector, and a rail pipe solenoid valve component. The high-pressure fuel supply pump draws fuel from the fuel tank, boosts the pressure, and supplies it to the rail pipe solenoid valve component. Under the control of an engine ECU, the rail pipe solenoid valve component supplies a certain amount of fuel to the fuel separator component at a certain time. The electronically controlled common rail fuel injection system with a single solenoid valve of the present invention uses a single solenoid valve component in combination with a fuel separator component to supply fuel to multiple mechanical fuel injectors, making the system cost much lower than a traditional electronically controlled common rail fuel injection system that requires a set of solenoid valve components for each injector.

Description

Technical Field

[0001] The present invention relates to the technical field of engine fuel injection systems, in particular to an electronically controlled common rail fuel injection system with a single solenoid valve. Background Art

[0002] The electronically controlled common rail injection system is a fuel injection technology used in diesel engines. Its core principle is to separate the generation of fuel pressure from the injection process. High-pressure fuel is stored in a "common rail" system, and the injection timing and quantity are precisely controlled by an electronic control system. A high-pressure fuel pump pressurizes the fuel and delivers it to the common rail, where it is stabilized and filtered to maintain a stable pressure. The engine ECU controls the solenoid valves based on operating conditions, ensuring that the injectors spray a fixed amount of fuel at fixed times into the combustion chamber to drive the engine. Traditional electronically controlled common rail injection systems require a set of solenoid valve components for each injector, resulting in high costs and challenges in cost control. Furthermore, individual differences among the multiple solenoid valve components can affect the consistency of injection from each injector. Summary of the Invention

[0003] The object of the present invention is to provide an electronically controlled common rail fuel injection system with a single solenoid valve to solve the problems raised in the above background technology.

[0004] To achieve the above objectives, the present invention provides the following technical solutions: a single-solenoid valve electronically controlled common rail injection system, comprising a high-pressure fuel supply pump, a fuel distributor assembly, a fuel tank, mechanical fuel injectors, and a rail pipe solenoid valve assembly. The high-pressure fuel supply pump draws fuel from the fuel tank, boosts the pressure, and supplies it to the rail pipe solenoid valve assembly. Under the control of the engine ECU, the rail pipe solenoid valve assembly supplies a certain amount of fuel to the fuel distributor assembly at a certain time. The fuel distributor assembly distributes the fuel to the mechanical fuel injectors of each cylinder of the diesel engine.

[0005] The rail pipe solenoid valve component includes a solenoid valve part and a common rail pipe. An oil storage chamber is opened in the common rail pipe. The fuel pressurized by the high-pressure fuel supply pump is input into the oil storage chamber. The communication state between the oil storage chamber and the oil separator component is controlled by the solenoid valve part.

[0006] A control valve core is installed on the solenoid valve part, and both the solenoid valve part and the control valve core are arranged at the end of the common rail pipe.

[0007] The rail tube solenoid valve component is also provided with an oil drain channel, a main oil channel, a capillary channel, a pressure balance chamber and a balance valve core;

[0008] The control valve core is used to control the opening and closing of the oil drain channel. The main oil channel is connected to the oil storage chamber. The pressure balance chamber is connected to the main oil channel through a capillary channel. One end of the oil drain channel is connected to the pressure balance chamber. The position of the balance valve core is controlled by the pressure balance of the pressure balance chamber and the main oil channel, thereby realizing the control of the connection state of the oil storage chamber and the oil distributor component. A spring is provided in the pressure balance chamber to support the balance valve core.

[0009] When the diesel engine does not need fuel, part of the fuel in the oil storage chamber enters the main oil channel, and part enters the pressure balance chamber through the capillary channel. At this time, the pressure at both ends of the balancing valve core is balanced, and the oil supply path is closed under the action of the spring force. At this time, the oil storage chamber and the oil separator components are not connected.

[0010] When the diesel engine needs fuel, the engine ECU sends a signal to the solenoid valve unit, causing the solenoid valve unit to generate electromagnetic force to open the control valve core. At this time, the oil drain channel is connected to the outside, and the fuel in the pressure balance chamber is leaked through the oil drain channel. Since the aperture of the oil drain channel is larger than the aperture of the capillary channel, the capillary channel cannot replenish fuel to the pressure balance chamber in time, causing the pressure in the pressure balance chamber to decrease. Under the action of the pressure difference, the balancing valve core overcomes the elastic force of the spring and moves open. The oil storage chamber is connected to the oil separator component through the main oil channel, allowing the fuel to enter the oil separator component.

[0011] A variable capacity component is installed at the end of the common rail pipe, and the volume change of the oil storage chamber is controlled by the variable capacity component.

[0012] The variable capacity assembly includes a threaded tube and a hexagonal cavity. Both the threaded tube and the hexagonal cavity have cavities therein and are fixedly connected to each other. The internal cavity of the threaded tube is connected to the oil storage cavity.

[0013] An inner convex annular rim is fixedly provided on the inner wall surface of the threaded tube, and a one-way sealing disk is provided on one side of the inner convex annular rim. When the one-way sealing disk contacts and cooperates with the inner convex annular rim, the threaded tube can be separated and closed, thereby reducing the volume of the oil storage chamber. When the one-way sealing disk is separated from the inner convex annular rim and opened, the threaded tube and the hexagonal cavity are connected to the oil storage chamber, thereby increasing the volume of the oil storage chamber.

[0014] A regulating shaft is fixedly provided on one side of the one-way sealing disk, and a sealing end sleeve is provided on the hexagonal cavity. The regulating shaft passes through the sealing end sleeve and is sealed with the sealing end sleeve.

[0015] An external driving part is fixedly provided at the end of the hexagonal cavity, and an air-controlled piston is provided in sealing contact with the inner portion of the external driving part. The air-controlled piston is fixedly connected to the regulating shaft, and a piston spring is provided on the side of the air-controlled piston facing the regulating shaft. By controlling the air pressure on the side of the air-controlled piston away from the regulating shaft, the position of the air-controlled piston is changed, thereby controlling the movement of the one-way blocking disk;

[0016] An air window is provided through the surface of the external driving part, through which the air pressure when the air-controlled piston moves is balanced; a positive-pressure air nozzle is provided on the outside of the external driving part, and a main valve is installed on the positive-pressure air nozzle. The positive-pressure air nozzle is connected to the side of the air-controlled piston away from the regulating shaft, and the main valve is used to control the on and off of the positive-pressure air nozzle.

[0017] The external drive part is also provided with a negative pressure acceleration module. When the one-way sealing disk moves toward the inner convex ring eaves to control the reduction of the volume of the oil storage chamber, the negative pressure acceleration module can accelerate the movement of the air control piston, thereby accelerating the movement of the one-way sealing disk, so that the volume of the oil storage chamber is reduced and the control delay is reduced.

[0018] The negative pressure acceleration module includes a conversion chamber provided inside the external drive unit and an active piston disposed inside the conversion chamber; the active piston and the conversion chamber are in sealed contact; a branch air pipe is provided between the positive pressure air nozzle and the conversion chamber, and a branch air pipe is installed on the branch air pipe, and the branch air pipe is not affected by the control of the main valve;

[0019] A beam microhole is opened through the active piston, a push-back spring is set on one side of the active piston, and a negative pressure chamber is opened inside the external driving part on the other side of the active piston, and a negative pressure piston is set in the negative pressure chamber. The negative pressure piston and the active piston are fixedly connected by a shaft.

[0020] The outer drive part is further provided with a negative pressure storage chamber, an air pumping path and an air exhaust path;

[0021] The negative pressure storage chamber is connected to the negative pressure chamber through an exhaust air path, and the negative pressure chamber is connected to the outside atmosphere through an exhaust air path. A first one-way valve is provided in the exhaust air path, and a second one-way valve is provided in the exhaust air path. The first one-way valve allows the gas in the negative pressure storage chamber to flow unidirectionally into the negative pressure chamber, and the second one-way valve allows the gas in the negative pressure chamber to flow unidirectionally toward the outside atmosphere.

[0022] A bridge tube is provided between the cavity on one side of the air-controlled piston away from the regulating shaft and the negative pressure storage cavity. A bridge tube solenoid valve is installed on the bridge tube to control the on and off of the bridge tube.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The single-solenoid valve electronically controlled common rail injection system of the present invention uses a single solenoid valve unit in combination with an oil distributor to supply fuel to multiple mechanical injectors, making the system cost much lower than a conventional electronically controlled common rail injection system that requires a set of solenoid valve components for each injector. The system eliminates the drawback of individual differences among the multiple solenoid valve components in conventional electronically controlled common rail injection systems, resulting in better injection consistency among the injectors. Furthermore, the electronically controlled common rail injection system can use conventional mechanical injectors, retaining the advantages of the common rail system of high injection pressure, precise control, and flexible and adjustable injection pattern, while taking into account the advantages of conventional mechanical injectors of mature technology and low cost.

[0025] 2. The variable volume component in the present invention cooperates with the common rail pipe, which can instantly reduce the volume of the oil storage chamber in the common rail pipe when the vehicle accelerates suddenly. As the volume decreases, the compressible space of the fuel in the common rail pipe becomes smaller. When the engine control unit issues an acceleration command, the pressure in the common rail pipe can rise more quickly, allowing the injector to reach the required injection pressure more quickly, thereby injecting fuel into the cylinder more timely, thereby improving the acceleration response performance of the engine; when the vehicle is idling or driving at low load, the volume of the oil storage chamber in the common rail pipe is actively increased, and the fuel pressure is better stabilized by the increase in volume, so that the fuel pressure fluctuation is smoother, providing stable fuel pressure for the injector, and reducing energy loss; and through the internal convex annular eaves and one-way sealing disk structure, under sudden acceleration conditions, when the internal pressure of the oil storage chamber doubles, the volume of the oil storage chamber can be reduced by cooperating with the inner convex annular eaves and the one-way sealing disk, and a one-way sealing effect is achieved at the same time, so that the greatly increased pressure will not act between the sealing end sleeve and the regulating shaft, and the sealing requirements for the regulating shaft are smaller.

[0026] 3. The present invention can control the movement of the one-way sealing disk through the cooperation of the external drive part and the air-controlled piston and other structures, and can accumulate negative pressure under idle and low-load conditions through the negative pressure acceleration module. During sudden acceleration, the closing speed of the one-way sealing disk is accelerated by the negative pressure, so that the system response delay under sudden acceleration conditions is lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a system block diagram of the electronically controlled common rail fuel injection system with a single solenoid valve according to the present invention.

[0028] Figure 2 This is a cross-sectional view of the rail pipe solenoid valve component of the present invention.

[0029] Figure 3 It is a cross-sectional view of the oil separator component of the present invention.

[0030] Figure 4 Schematic diagram of the variable capacitance component of the present invention.

[0031] Figure 5 This is the front view of the variable capacitance component of the present invention.

[0032] Figure 6 This is a top view of the variable capacitance component of the present invention.

[0033] Figure 7 This is a three-dimensional half-section diagram of the variable capacitance component of the present invention.

[0034] Figure 8 This is a partial three-dimensional half-section front view of the variable capacitance component of the present invention.

[0035] In the figure: 1. High-pressure fuel supply pump; 2. Oil distributor component; 3. Fuel tank; 4. Mechanical fuel injector; 5. Rail solenoid valve component; 6. Solenoid valve part; 7. Control valve core; 8. Oil drain channel; 9. Oil storage chamber; 10. Common rail pipe; 11. Main oil channel; 12. Capillary channel; 13. Pressure balance chamber; 14. Balance valve core; 15. Oil distribution plunger; 16. Oil distribution groove; 17. Oil outlet valve seat component; 18. Variable capacity component; 101. Threaded pipe; 102. Hexagonal cavity; 103. Inner convex ring; 104. One-way blocking disk; 105. Control shaft; 106. Sealing End sleeve; 107, external drive unit; 108, air-controlled piston; 109, piston spring; 110, air window; 111, positive-pressure air nozzle; 112, main valve; 113, conversion chamber; 114, active piston; 115, branch air pipe; 116, branch valve; 117, beam micropore; 118, push-back spring; 119, negative-pressure chamber; 120, negative-pressure piston; 121, negative-pressure storage chamber; 122, exhaust air path; 123, exhaust air path; 124, first one-way valve; 125, second one-way valve; 126, bridge pipe; 127, bridge solenoid valve. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] See also Figures 1 to 8 The present invention provides a technical solution: a single-solenoid valve electronically controlled common rail injection system, comprising a high-pressure fuel supply pump 1, a fuel distributor component 2, a fuel tank 3, a mechanical fuel injector 4, and a rail pipe solenoid valve component 5. The high-pressure fuel supply pump 1 draws fuel from the fuel tank 3, boosts the pressure, and supplies it to the rail pipe solenoid valve component 5. Under the control of the engine ECU, the rail pipe solenoid valve component 5 supplies a certain amount of fuel to the fuel distributor component 2 at a certain time. The fuel distributor component 2 distributes the fuel to the mechanical fuel injectors 4 of each cylinder of the diesel engine; Figure 3As shown in FIG, the oil distributor component 2 is provided with an oil distribution plunger 15, an oil distribution groove 16, and an oil outlet valve seat component 17. The camshaft of the high-pressure oil supply pump 1 drives the oil distribution plunger 15 in the oil distributor component 2 to rotate. The high-pressure oil enters the corresponding oil channel through the oil distribution groove 16, passes through the corresponding oil outlet valve seat component 17, and then reaches the corresponding mechanical injector 4 through the high-pressure oil pipe, spraying the high-pressure fuel into the corresponding combustion chamber of the diesel engine for combustion and power generation. When the fuel injection amount reaches the diesel engine combustion requirement, the pulse signal of the electronic control unit ECU is terminated, the rail pipe solenoid valve component 5 is closed, and the oil circuit is no longer supplied with fuel. The oil distribution plunger 15 of the oil distributor component 2 rotates synchronously under the drive of the camshaft, and the oil distribution groove 16 is disconnected from the corresponding oil channel and rotates to the next oil channel that needs oil supply. This cycle repeats itself. According to the ignition sequence of each cylinder of the diesel engine, the electronically controlled common rail injection system of the single solenoid valve of the present invention continuously injects diesel into the corresponding cylinder of the diesel engine for combustion and power generation.

[0038] The rail pipe solenoid valve component 5 includes a solenoid valve part 6 and a common rail pipe 10. An oil storage chamber 9 is opened in the common rail pipe 10. The fuel pressurized by the high-pressure fuel supply pump 1 is input into the oil storage chamber 9. The communication state between the oil storage chamber 9 and the oil separator component 2 is controlled by the solenoid valve part 6.

[0039] A control valve core 7 is mounted on the solenoid valve portion 6 , and both the solenoid valve portion 6 and the control valve core 7 are disposed at the end of the common rail pipe 10 .

[0040] The rail pipe solenoid valve component 5 is also provided with an oil drain channel 8, a main oil channel 11, a capillary channel 12, a pressure balance chamber 13 and a balance valve core 14; the control valve core 7 is used to control the opening and closing of the oil drain channel 8, the main oil channel 11 is connected to the oil storage chamber 9, the pressure balance chamber 13 is connected to the main oil channel 11 through the capillary channel 12, and one end of the oil drain channel 8 is connected to the pressure balance chamber 13. The position of the balance valve core 14 is controlled by the pressure balance of the pressure balance chamber 13 and the main oil channel 11, thereby realizing the control of the communication state of the oil storage chamber 9 and the oil distributor component 2. A spring is provided in the pressure balance chamber 13 to support the balance valve core 14.

[0041] When the diesel engine does not need fuel, some of the fuel in the oil reservoir 9 flows into the main oil gallery 11, and some flows into the pressure balance chamber 13 through the capillary passage 12. At this point, the pressure at both ends of the balancing valve core 14 is balanced, and the spring force closes the oil supply path. This disconnects the oil reservoir 9 from the oil separator 2. When the diesel engine needs fuel, the engine ECU sends a signal to the solenoid valve 6, causing it to generate electromagnetic force to open the control valve core 7. This opens the drain passage 8, allowing the fuel in the pressure balance chamber 13 to drain through it. Because the diameter of the drain passage 8 is larger than that of the capillary passage 12, the capillary passage 12 cannot replenish the fuel in the pressure balance chamber 13 in a timely manner, causing the pressure in the pressure balance chamber 13 to drop. Under the pressure differential, the balancing valve core 14 overcomes the spring force and moves open, connecting the oil reservoir 9 to the oil separator 2 through the main oil gallery 11, allowing fuel to enter the oil separator 2.

[0042] A variable capacity assembly 18 is installed at the end of the common rail pipe 10 , and the volume change of the oil storage chamber 9 is controlled by the variable capacity assembly 18 .

[0043] The variable capacity assembly 18 includes a threaded tube 101 and a hexagonal cavity 102. Both the threaded tube 101 and the hexagonal cavity 102 have cavities therein and are fixedly connected to each other. The internal cavity of the threaded tube 101 is connected to the oil storage chamber 9.

[0044] An inner convex annular rim 103 is fixedly provided on the inner wall surface of the threaded tube 101, and a one-way sealing disk 104 is provided on one side of the inner convex annular rim 103. When the one-way sealing disk 104 contacts and cooperates with the inner convex annular rim 103, the threaded tube 101 can be separated and closed, thereby reducing the volume of the oil storage chamber 9. When the one-way sealing disk 104 is separated from the inner convex annular rim 103 and opened, the threaded tube 101 and the hexagonal cavity 102 are connected with the oil storage chamber 9, so that the volume of the oil storage chamber 9 increases.

[0045] A regulating shaft 105 is fixedly provided on one side of the one-way sealing disk 104 , and a sealing end sleeve 106 is provided on the hexagonal cavity 102 . The regulating shaft 105 passes through the sealing end sleeve 106 and is sealed with the sealing end sleeve 106 .

[0046] An external drive portion 107 is fixedly provided at the end of the hexagonal cavity 102. An air-controlled piston 108 is provided in sealing contact with the interior of the external drive portion 107. The air-controlled piston 108 is fixedly connected to the regulating shaft 105. A piston spring 109 is provided on the side of the air-controlled piston 108 facing the regulating shaft 105. By controlling the air pressure on the side of the air-controlled piston 108 away from the regulating shaft 105, the position of the air-controlled piston 108 is changed, thereby controlling the movement of the one-way blocking disk 104.

[0047] An air window 110 is provided through the surface of the external driving part 107, and the air pressure when the air control piston 108 moves is balanced through the air window 110; a positive pressure air nozzle 111 is provided on the outside of the external driving part 107, and a main valve 112 is installed on the positive pressure air nozzle 111. The positive pressure air nozzle 111 is connected to the side of the air control piston 108 away from the regulating shaft 105, and the main valve 112 is used to control the on and off of the positive pressure air nozzle 111.

[0048] A negative pressure acceleration module is also provided on the external driving part 107. When the one-way sealing disk 104 moves toward the inner convex annular eave 103 to control the reduction of the volume of the oil storage chamber 9, the negative pressure acceleration module can accelerate the movement of the air control piston 108, thereby accelerating the movement of the one-way sealing disk 104, so that the volume reduction control delay of the oil storage chamber 9 is reduced.

[0049] The negative pressure acceleration module includes a conversion chamber 113 provided within the external drive unit 107 and an active piston 114 disposed within the conversion chamber 113. The active piston 114 and the conversion chamber 113 are in sealed contact with each other. A branch air pipe 115 is provided between the positive pressure air nozzle 111 and the conversion chamber 113. A branch air pipe 115 is installed on the branch air pipe 115, and the branch air pipe 115 is not affected by the control of the main valve 112.

[0050] A beam microhole 117 is provided through the active piston 114, and a push-back spring 118 is provided on one side of the active piston 114. A negative pressure chamber 119 is provided inside the external driving part 107 on the other side of the active piston 114, and a negative pressure piston 120 is provided in the negative pressure chamber 119. The negative pressure piston 120 and the active piston 114 are fixedly connected by a shaft.

[0051] The outer driving part 107 is further provided with a negative pressure storage chamber 121, an air extraction path 122 and an air exhaust path 123;

[0052] The negative pressure storage chamber 121 is connected to the negative pressure chamber 119 through the exhaust air path 122, and the negative pressure chamber 119 is connected to the outside atmosphere through the exhaust air path 123. A first one-way valve 124 is provided in the exhaust air path 122, and a second one-way valve 125 is provided in the exhaust air path 123. The first one-way valve 124 allows the gas in the negative pressure storage chamber 121 to flow unidirectionally toward the negative pressure chamber 119, and the second one-way valve 125 allows the gas in the negative pressure chamber 119 to flow unidirectionally toward the outside atmosphere.

[0053] A bridge tube 126 is provided between the cavity on the side of the air control piston 108 away from the regulating shaft 105 and the negative pressure storage chamber 121. A bridge tube solenoid valve 127 is installed on the bridge tube 126 to control the opening and closing of the bridge tube 126 through the bridge tube solenoid valve 127.

[0054] The variable capacitance component 18 of the present invention is used as follows Figure 2 As shown in , it is installed at the end of the common rail pipe 10 so that the threaded pipe 101 is connected to the oil storage chamber 9; Figure 7 At this time, the volume of the oil storage chamber 9 includes the internal cavity of the threaded tube 101 and the hexagonal cavity 102, so that the volume of the oil storage chamber 9 increases. When the inner convex ring 103 and the one-way sealing disk 104 are closed together, the oil storage chamber 9 loses the internal cavity of the threaded tube 101 and the hexagonal cavity 102, so that the volume of the oil storage chamber 9 decreases.

[0055] When the diesel engine is idling or at low load, the engine only needs to maintain the minimum operation, the injection volume is small, the common rail pipe 10 only needs to meet the basic injection requirements, and the internal pressure of the oil storage chamber 9 is relatively low; during rapid acceleration, the high-pressure oil pump supplies oil at full speed, the oil volume increases significantly, and the internal pressure of the oil storage chamber 9 increases significantly. When idling or at low load, the inner convex annular rim 103 and the one-way blocking disk 104 separate and open, and the volume of the oil storage chamber 9 increases. During rapid acceleration, the one-way blocking disk 104 fits tightly against the inner convex annular rim 103, and the one-way blocking disk 104 has a one-way sealing effect. When the internal pressure of the oil storage chamber 9 increases significantly, the pressure acts on the end face of the one-way blocking disk 104, thereby preventing the increased pressure from acting between the sealing end sleeve 106 and the regulating shaft 105; the sealing requirement between the sealing end sleeve 106 and the regulating shaft 105 is sufficient to meet the pressure requirements of the oil storage chamber 9 under idling conditions, thereby reducing the probability of diesel leakage at the sealing end sleeve 106 and the regulating shaft 105.

[0056] The high-pressure diesel fuel boosted by the high-pressure fuel pump 1 is input into the fuel storage chamber 9, and then transported to the oil distributor component 2 through the fuel storage chamber 9. Since diesel fuel has a certain compressibility under high pressure, the fuel storage chamber 9 can buffer and filter the fuel, reducing the pulse fluctuations generated by the high-pressure fuel pump 1. During rapid acceleration, the volume of the fuel storage chamber 9 decreases, and the compressible space for fuel in the fuel storage chamber 9 becomes smaller. When the engine control unit issues an acceleration command, the pressure in the fuel storage chamber 9 can rise more quickly, allowing the mechanical injector 4 to reach the required injection pressure more quickly, thereby injecting fuel into the cylinder more promptly and improving the acceleration response performance of the engine. When the vehicle is idling or running at low load, the volume of the fuel storage chamber 9 in the common rail pipe 10 is actively increased. The increase in volume can better stabilize the fuel pressure, making the fuel pressure fluctuation smoother, providing a stable fuel pressure for the mechanical injector 4, and reducing energy loss.

[0057] When in use, the positive pressure gas nozzle 111 is connected to a positive pressure gas source, such as Figure 8As shown in, when the main valve 112 is opened, positive pressure gas enters the interior of the external drive part 107 through the positive pressure gas nozzle 111, driving the air control piston 108 to move to the left, compressing the piston spring 109, and at this time the one-way sealing disk 104 is driven to move to the left by the regulating shaft 105, and the one-way sealing disk 104 is separated from the inner convex ring eaves 103 and opened, and the volume of the oil storage chamber 9 is increased. The increase in the volume of the oil storage chamber 9 is for switching to idle or low load conditions. At this time, a very high response speed is not required, and the low movement speed of the one-way sealing disk 104 will not bring negative effects.

[0058] However, when the one-way blocking disk 104 is closed, facing a rapid acceleration condition, if the response delay is too long, it will affect the acceleration feeling and increase the power hysteresis problem. The negative pressure acceleration module is set to complete the negative pressure charging by controlling the intermittent opening and closing of the branch valve 116.

[0059] When the branch valve 116 is opened, the positive pressure in the positive pressure nozzle 111 enters the conversion chamber 113 through the branch air pipe 115, pushing the active piston 114 to the right. When the branch valve 116 is closed, the elastic pressure applied by the push-back spring 118 makes the active piston 114 have a tendency to move to the left. In the above process, the beam microhole 117 continues to exhaust the beam. When the active piston 114 moves to the right, since the intake flow rate of the branch air pipe 115 is much greater than the exhaust flow rate of the beam microhole 117, it does not affect the rightward movement of the active piston 114. After the branch valve 116 is closed, as the beam microhole 117 gradually discharges the gas, the elastic force of the push-back spring 118 causes the active piston 114 to move to the left and reset. As a result, the active piston 114 shows a reciprocating movement, and the driving force for the rightward movement is extremely large.

[0060] The negative pressure piston 120 is driven to move back and forth by the active piston 114, and according to the principle of the pressure formula, since the piston area of ​​the negative pressure piston 120 is smaller than the piston area of ​​the active piston 114, the pressure can be increased, so that during the reciprocating movement, the negative pressure piston 120 cooperates with the first one-way valve 124 and the second one-way valve 125 to evacuate the negative pressure storage chamber 121, so that the interior of the negative pressure storage chamber 121 is in a highly negative pressure state.

[0061] When the engine receives a sudden acceleration command and needs to control the one-way sealing disk 104 to close, it only needs to control the bridge solenoid valve 127 to open. The negative pressure storage chamber 121 uses a greater negative pressure suction force to evacuate the interior of the external drive part 107 through the bridge tube 126, so that the air control piston 108 moves quickly to the right to its position, thereby improving the response speed.

[0062] Under frequent rapid acceleration conditions, if the negative pressure in the negative pressure storage chamber 121 does not have time to accumulate, when the bridge solenoid valve 127 is opened, the air pressure on one side of the air control piston 108 will be discharged outward through the bridge tube 126, the negative pressure storage chamber 121, the exhaust air path 122, the negative pressure chamber 119 and the exhaust air path 123 under the elastic thrust of the piston spring 109, so that the air control piston 108 moves right to its full position, ensuring that the one-way blocking disk 104 can be closed, but the corresponding speed will be slowed down. Therefore, under frequent rapid acceleration conditions, it is preferred to switch the engine to the corresponding mode, control the one-way blocking disk 104 to remain closed, and temporarily not switch to the expansion mode of the oil storage chamber 9.

[0063] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An electronically controlled common rail fuel injection system with a single solenoid valve, comprising a high-pressure fuel supply pump, an oil distributor, a fuel tank, a mechanical fuel injector, and a rail pipe solenoid valve component, characterized in that: The high-pressure fuel supply pump draws fuel from the fuel tank, boosts its pressure, and then supplies it to the rail pipe solenoid valve component. Under the control of the engine ECU, the rail pipe solenoid valve component supplies a certain amount of fuel to the oil distributor component at a certain time, and the oil distributor component distributes the fuel to the mechanical injectors of each cylinder of the diesel engine; The rail solenoid valve component includes a solenoid valve portion and a common rail pipe. The common rail pipe is provided with an oil storage chamber. The fuel pressurized by the high-pressure fuel supply pump is input into the oil storage chamber. The solenoid valve portion controls the communication state between the oil storage chamber and the oil distributor component. The solenoid valve part is equipped with a control valve core; the rail tube solenoid valve component is also provided with an oil drain channel, a main oil channel, a capillary channel, a pressure balance chamber and a balance valve core; The control valve core is used to control the opening and closing of the oil drain channel. The main oil channel is connected to the oil storage chamber, and the pressure balance chamber is connected to the main oil channel through a capillary channel. One end of the oil drain channel is connected to the pressure balance chamber. The position of the balance valve core is controlled by the pressure balance of the pressure balance chamber and the main oil channel, thereby realizing the communication state control of the oil storage chamber and the oil separator component. A spring is provided in the pressure balance chamber to support the balance valve core; when the diesel engine does not need fuel, part of the fuel in the oil storage chamber enters the main oil channel, and part enters the pressure balance chamber through the capillary channel. At this time, the pressure at both ends of the balance valve core is balanced, and the oil supply path is closed under the action of the spring force. At this time, the oil storage chamber and the oil separator component are not connected; a variable capacity component is installed at the end of the common rail pipe, and the volume change of the oil storage chamber is controlled by the variable capacity component; the variable capacity component includes a threaded tube and a hexagonal cavity, and the threaded tube and the hexagonal cavity are both provided with cavities, and the two are fixedly connected to each other, and the internal cavity of the threaded tube is connected to the oil storage chamber; An inner convex annular rim is fixedly provided on the inner wall surface of the threaded tube, and a one-way sealing disk is provided on one side of the inner convex annular rim. When the one-way sealing disk contacts and cooperates with the inner convex annular rim, the threaded tube can be separated and closed, thereby reducing the volume of the oil storage chamber. When the one-way sealing disk is separated from the inner convex annular rim and opened, the threaded tube and the hexagonal cavity are connected to the oil storage chamber, thereby increasing the volume of the oil storage chamber.

2. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 1, characterized in that: The solenoid valve portion and the control valve core are both arranged at the end of the common rail pipe.

3. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 2, characterized in that: When the diesel engine needs fuel, the engine ECU sends a signal to the solenoid valve unit, causing the solenoid valve unit to generate electromagnetic force to open the control valve core. At this time, the oil drain channel is connected to the outside, and the fuel in the pressure balance chamber is leaked through the oil drain channel. Since the aperture of the oil drain channel is larger than the aperture of the capillary channel, the capillary channel cannot replenish fuel to the pressure balance chamber in time, causing the pressure in the pressure balance chamber to decrease. Under the action of the pressure difference, the balancing valve core overcomes the elastic force of the spring and moves open. The oil storage chamber is connected to the oil separator component through the main oil channel, allowing the fuel to enter the oil separator component.

4. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 1, characterized in that: A regulating shaft is fixedly provided on one side of the one-way sealing disk, a sealing end sleeve is provided on the hexagonal cavity, and the regulating shaft passes through the sealing end sleeve and is sealed with the sealing end sleeve.

5. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 4, characterized in that: An external driving part is fixedly provided at the end of the hexagonal cavity, and an air-controlled piston is provided in sealing contact with the inner portion of the external driving part. The air-controlled piston is fixedly connected to the regulating shaft, and a piston spring is provided on the side of the air-controlled piston facing the regulating shaft. By controlling the air pressure on the side of the air-controlled piston away from the regulating shaft, the position of the air-controlled piston is changed, thereby controlling the movement of the one-way blocking disk; An air window is provided through the surface of the external driving part, through which the air pressure when the air-controlled piston moves is balanced; a positive-pressure air nozzle is provided on the outside of the external driving part, and a main valve is installed on the positive-pressure air nozzle. The positive-pressure air nozzle is connected to the side of the air-controlled piston away from the regulating shaft, and the main valve is used to control the on and off of the positive-pressure air nozzle.

6. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 5, characterized in that: The external drive part is also provided with a negative pressure acceleration module. When the one-way sealing disk moves toward the inner convex ring eaves to control the reduction of the volume of the oil storage chamber, the negative pressure acceleration module can accelerate the movement of the air control piston, thereby accelerating the movement of the one-way sealing disk, so that the volume of the oil storage chamber is reduced and the control delay is reduced.

7. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 6, characterized in that: The negative pressure acceleration module includes a conversion chamber provided inside the external drive unit and an active piston disposed inside the conversion chamber; the active piston and the conversion chamber are in sealed contact; a branch air pipe is provided between the positive pressure air nozzle and the conversion chamber, and a branch air pipe is installed on the branch air pipe, and the branch air pipe is not affected by the control of the main valve; A beam microhole is opened through the active piston, a push-back spring is set on one side of the active piston, and a negative pressure chamber is opened inside the external driving part on the other side of the active piston, and a negative pressure piston is set in the negative pressure chamber. The negative pressure piston and the active piston are fixedly connected by a shaft.

8. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 7, characterized in that: The outer drive part is further provided with a negative pressure storage chamber, an air pumping path and an air exhaust path; The negative pressure storage chamber is connected to the negative pressure chamber through an exhaust air path, and the negative pressure chamber is connected to the outside atmosphere through an exhaust air path. A first one-way valve is provided in the exhaust air path, and a second one-way valve is provided in the exhaust air path. The first one-way valve allows the gas in the negative pressure storage chamber to flow unidirectionally into the negative pressure chamber, and the second one-way valve allows the gas in the negative pressure chamber to flow unidirectionally toward the outside atmosphere.

9. The electronically controlled common rail fuel injection system with a single solenoid valve according to claim 8, characterized in that: A bridge tube is provided between the cavity on one side of the air-controlled piston away from the regulating shaft and the negative pressure storage cavity. A bridge tube solenoid valve is installed on the bridge tube to control the on and off of the bridge tube.

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