EP1520099B1 - Boosted fuel injector with rapid pressure reduction at end of injection - Google Patents

Boosted fuel injector with rapid pressure reduction at end of injection Download PDF

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Publication number
EP1520099B1
EP1520099B1 EP20030722254 EP03722254A EP1520099B1 EP 1520099 B1 EP1520099 B1 EP 1520099B1 EP 20030722254 EP20030722254 EP 20030722254 EP 03722254 A EP03722254 A EP 03722254A EP 1520099 B1 EP1520099 B1 EP 1520099B1
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EP
European Patent Office
Prior art keywords
pressure
valve
space
characterized
device according
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EP20030722254
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German (de)
French (fr)
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EP1520099A1 (en
Inventor
Hans-Christoph Magel
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Robert Bosch GmbH
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Robert Bosch GmbH
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Priority to DE10229419 priority Critical
Priority to DE2002129419 priority patent/DE10229419A1/en
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Priority to PCT/DE2003/001098 priority patent/WO2004003376A1/en
Publication of EP1520099A1 publication Critical patent/EP1520099A1/en
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Publication of EP1520099B1 publication Critical patent/EP1520099B1/en
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M57/00Fuel-injectors combined or associated with other devices
    • F02M57/02Injectors structurally combined with fuel-injection pumps
    • F02M57/022Injectors structurally combined with fuel-injection pumps characterised by the pump drive
    • F02M57/025Injectors structurally combined with fuel-injection pumps characterised by the pump drive hydraulic, e.g. with pressure amplification
    • F02M57/026Construction details of pressure amplifiers, e.g. fuel passages or check valves arranged in the intensifier piston or head, particular diameter relationships, stop members, arrangement of ports or conduits
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M45/00Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M47/00Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure
    • F02M47/02Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure of accumulator-injector type, i.e. having fuel pressure of accumulator tending to open, and fuel pressure in other chamber tending to close, injection valves and having means for periodically releasing that closing pressure
    • F02M47/027Electrically actuated valves draining the chamber to release the closing pressure
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M57/00Fuel-injectors combined or associated with other devices
    • F02M57/02Injectors structurally combined with fuel-injection pumps
    • F02M57/022Injectors structurally combined with fuel-injection pumps characterised by the pump drive
    • F02M57/025Injectors structurally combined with fuel-injection pumps characterised by the pump drive hydraulic, e.g. with pressure amplification
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/02Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type
    • F02M59/10Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by the piston-drive
    • F02M59/105Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by the piston-drive hydraulic drive

Description

    Technical area
  • To supply combustion chambers of self-igniting internal combustion engines with fuel, both pressure-controlled and stroke-controlled injection systems can be used. As fuel injection systems come next pump-injector units, pump-line-nozzle units and storage injection systems are used. Storage injection systems (common rail injection systems) advantageously make it possible to adapt the injection pressure to the load and speed of the internal combustion engine in each case. In order to achieve high specific performance and to reduce the emissions of the internal combustion engine, the highest possible injection pressure is generally required.
  • State of the art
  • For reasons of strength, the achievable pressure level is currently limited to about 1600 bar in today used storage injection systems. To further increase the pressure on accumulator injection systems, pressure amplifiers are used on Commen Rail systems.
  • EP 0 562 046 B1 discloses a control and valve arrangement with damping for an electronically controlled injection unit. The actuation and valve assembly for a hydraulic unit comprises an electrically energizable electromagnet having a fixed stator and a movable armature. The anchor has a first and a second surface. The first and second surfaces of the armature define first and second cavities, with the first surface of the armature facing the stator. It is provided a valve which is connected to the armature. The valve is capable of delivering a hydraulic actuating fluid to the injector from a sump. A damping fluid may be collected therefrom with respect to one of the cavities of the solenoid assembly. By means of a projecting into a central bore portion of a valve, the flow connection of the damping fluid can be selectively released or closed proportional to its viscosity.
  • WO 02/092997 A1 relates to a fuel injection device. This is used on an internal combustion engine. The combustion chambers of the internal combustion engine are each supplied with fuel via fuel injectors. The fuel injectors are acted upon by a high pressure source; Furthermore, the fuel injection device according to WO 02/092997 A1 comprises a pressure booster, which contains a movable pressure booster piston, which separates a connectable to the high pressure source chamber from a connected to the fuel injector high-pressure chamber. The fuel pressure in the high pressure chamber can be varied by filling a back space of the pressure booster with fuel or by emptying this back space of fuel.
  • The fuel injector comprises a movable closing piston for opening or closing the injection openings facing the combustion chamber. The closing piston protrudes into a closing pressure chamber so that it can be pressurized with fuel. This achieves a force acting on the closing piston in the closing direction. The closing pressure chamber and another space are formed by a common working space, wherein all portions of the working space are permanently connected to each other for the exchange of fuel.
  • With this solution can be achieved by controlling the pressure booster on the back space that the drive losses in the high-pressure fuel system compared to a control of a temporarily connected to the high-pressure fuel source working space can be kept low. Furthermore, the high-pressure chamber is relieved only up to the pressure level of the high pressure accumulator and not up to leak pressure level. On the one hand this improves the hydraulic efficiency of the fuel injector, on the other hand, a faster pressure build-up can take place up to the system pressure level, so that the time intervals lying between the injection phases can be shortened.
  • With this solution, a variable hydraulic closing force acting on the nozzle needle of the fuel injector can be achieved. As a result, a variable nozzle opening pressure is achieved, which increases with the pressure prevailing in the high-pressure reservoir, so that even with small amounts, a high injection pressure is achieved and the needle closing can be improved. In order to realize this hydraulic closing force with little design effort, the pressure prevailing in the high-pressure reservoir pressure is applied directly to the back of the nozzle needle. To increase the efficiency of the pressure booster is controlled according to this solution on the back space, which then acts as a pressure booster control chamber. As a result, only the smaller rear space and not the large working space of the pressure intensifier is relieved; In addition, the high pressure area is only up to the pressure prevailing in the high pressure accumulator space and not up to leakage pressure level relieved, whereby the hydraulic efficiency of such an arrangement can be significantly improved. This leads to an injection system for self-igniting internal combustion engines with high achievable injection pressure and at the same time increased efficiency. For the control, however, a 3/2-way valve is necessary to ensure a rapid pressure reduction at the injection end. However, a 3/2-way valve is fenigungstechnisch very expensive to produce and costly. The required tolerances are currently not controllable in mass production.
  • In principle, it is possible to control a pressure-translating fuel injector according to the solution known from WO 02/092997 A1 with a 2/2-way valve in conjunction with a filling throttle. To accelerate the resetting and to reduce the amount lost through the filling throttle can be used advantageously a filling valve. When using a filling valve, however, results in a slow pressure drop at the injection end except for the pressure prevailing in the high-pressure reservoir pressure level, which leads to poor emission results. A rapid pressure drop (rapid spill) is therefore imperative to meet future exhaust emission limits. Furthermore, the disadvantage is associated with a slow pressure reduction towards the end of an injection phase, that the average injection pressure level is significantly reduced.
  • Presentation of the invention
  • The proposed solution according to the invention avoids both the use of a designed as a 312-way valve control valve and the disadvantages associated with the use of a 2/2-way valve with Fülldrossel or filling valve, d. H. a slower pressure drop towards the end of the injection. With the proposed solution according to the invention, the filling throttle and the filling valve are replaced by a pressure relief valve, via which, however, a very rapid pressure reduction can be achieved at the end of an injection process. The rapid pressure reduction (rapid spill) at the end of the injection phase in turn significantly improves the emission levels of the exhaust gas of self-igniting internal combustion engines.
  • The pressure relief valve is integrated in the control line to relieve the control chamber of the pressure booster. The valve body of the Druckentlasungsventils can be formed both as a cylindrical body and include an area which can be formed in a reduced diameter, for example as a constriction. The end faces of the valve body of the pressure relief valve can both be the same hydraulically effective surfaces and have different diameters. At the pressure relief valve, two opposing hydraulic chambers may be formed, which pass through a through hole in the valve body of the pressure relief valve communicate with each other. The flow cross section of the through bore within the valve body of the pressure relief valve is selected so that a pressure difference builds up between the hydraulic chambers of the pressure relief valve, so that the pressure relief valve can be kept closed.
  • By using a metering valve designed as a 2/2-way valve, it is possible to avoid the use of a 3/2-way valve that is expensive to produce and therefore expensive in terms of the required tolerance. The use of a pressure relief valve in the control line of the pressure booster allows a rapid pressure drop at the end of the injection, which can achieve a rapid closing of an example designed as a nozzle needle injection valve member.
  • drawing
  • With reference to the drawing, the invention will be described below in more detail.
  • It shows:
  • FIG. 1
    a known pressure-translated fuel injector with parallel-connected filling valve and filling throttle with slow pressure reduction behavior,
    FIG. 2
    an inventive, pressure-translated fuel injector with 2/2-way metering valve and relief valve in the control line of the control chamber of the pressure booster,
    FIG. 3
    the pressure-translated fuel injector according to Figure 2 in the activated state,
    FIG. 4
    the pressure-translated fuel injector according to FIG. 2 with a relief valve with a sealing seat,
    FIG. 5
    the pressure-translated fuel injector as shown in Figure 2 with relief valve with a cylindrically shaped valve body.
    variants
  • FIG. 1 shows a known pressure-intensified fuel injector with a parallel-connected filling valve and filling throttle, which has a slow pressure reduction behavior.
  • The fuel injection device shown in Figure 1 comprises a fuel injector 1, and a high-pressure accumulator chamber 2 (common rail). The fuel injector 1 contains an injector body 3, a nozzle body 4, wherein a pressure booster 5 is received in the injector body 3 and a metering valve 6, which is formed in the arrangement shown in Figure 1 as a 2/2-way valve. By means of the fuel injector 1 high-pressure fuel is injected into a combustion chamber 7 of a self-igniting internal combustion engine.
  • From the metering valve 6 from a low-pressure side return 8 extends into a fuel tank, not shown, for. B. the fuel tank of a motor vehicle.
  • From high-pressure accumulator 2 (common rail) under high pressure fuel flows via a supply line 9 into a working space 10 of the pressure booster 5 a. The pressure booster 5 further comprises a control chamber 11 which is separated by a piston 12 from the working space 10 of the pressure booster 5. The piston 12 of the pressure booster 5 may be formed in one piece as well as in several parts. In the embodiment according to FIG. 1, the piston 12 of the pressure booster comprises a first partial piston 13 and a second partial piston 14. The first partial piston 13 is formed in a first diameter, while the second partial piston 14, which interposes a return spring stop surface 18 on the first partial piston 13 is applied, is formed in a reduced diameter. Within the control chamber 11 of the pressure booster 5, a return spring 17 is received, which is supported on the one hand on an abutment 16 which is formed by the bottom of the control chamber 11 in the injector body 3, and on the other hand rests against the aforementioned return spring stop 18. The lower end face of the second partial piston 14 of the piston 12 acts on a compression chamber 15 of the pressure booster 5, which in turn passes through a fuel inlet 21 under high pressure fuel into a nozzle chamber 22 within the nozzle body 4 of the fuel injector 1.
  • In the from the high-pressure accumulator 2 to the working chamber 10 of the pressure booster 5 extending supply line 9, a throttle body 19 may be added, which serves to dampen when closing or opening of the fuel injector 1 adjusting pressure pulsations in the supply line 9, their unattenuated reaction in the interior the high pressure accumulator 2 there would have unacceptably high pressure peaks result. From the supply line 9, which opens at an outlet point 38 in the working space 10 of the pressure booster 5, a throttle branch 36 extends to the working space 11 of the pressure booster 5, in which a Fülldrossel 35 is added. Parallel to the throttle branch 35 with integrated Fülldrossel 35, a filling valve 37 is connected, which in the illustrated in Figure 1 Embodiment variant of a fuel injection device is designed as a ball valve with an opening spring. The filling valve 37 is parallel to the throttle point 35 in the throttle branch 36 and opens into the same line as the throttle branch 36, which in turn opens into the working space 11 of the pressure booster 5
  • The control chamber 11 of the pressure booster 5 is connected via a control line 20 with the metering valve 6 in connection. From the control room 11 branches off beyond a connecting line 25, which in turn opens into a nozzle control chamber 24. A recorded in the nozzle control chamber 24 closing spring element 28 acts on an upper end face 27 of an injection valve member 26, which z. B. may be formed as a nozzle needle. Within the nozzle control chamber 24, a stop 29 is received, which is surrounded by the formed as a spiral spring closing spring element 28. From the nozzle control chamber 24 branches off a filling line 23, in which a check valve 34 is received. About the filling line 23 of the compression chamber 15 of the pressure booster 5 is filled with fuel.
  • The nozzle body 4 of the fuel injector 1 according to the arrangement in Figure 1 receives a nozzle chamber 22 which is supplied via the aforementioned fuel inlet 21 from the compression chamber 15 with fuel under high pressure. The injection valve member 26 includes a pressure shoulder 30 which, when a high pressure is present within the nozzle chamber 22, moves the injection valve member 26 against the action of the closing spring 28 in the opening direction. From the nozzle chamber 22 extends within the nozzle body 4, an annular gap 32 in the direction of the tip 31 of the injection valve member 26. About the annular gap 32, the fuel flows to injection ports 33. About the injection openings 33 of the fuel at the open, d. H. From its combustion chamber side seat moving injection valve member 26 injected into the combustion chamber 7 of the self-igniting internal combustion engine. The variant of a fuel injection device shown in Figure 1 sets as a metering valve 6 a 2/2-way valve, which is provided to accelerate the return and to reduce the outflowing loss amount with a filling throttle 35 parallel valve 37. However, the arrangement shown in Figure 1 has the disadvantage that at the end of the injection process, a slow pressure drop to the pressure in the high-pressure reservoir 2 (common rail) present pressure level This leads to unsatisfactory emissions results, also by a slowly settling pressure reduction achievable average injection pressure decreases.
  • Figure 2 shows an inventively designed, pressure-translated fuel injector with 2/2-way metering valve and a relief valve in the control line for controlling the pressure in the control chamber of the pressure booster.
  • In the embodiment of a fuel injection device according to the invention shown in Figure 2, a pressure-intensified fuel injector 1 is shown, the metering valve 6 can be configured as 2/2-way valve, in the control line 20 to the control chamber 11 of the pressure booster 5 an additional, the filling throttle and the filling valve 37 replacing pressure relief valve 40 is integrated. With this configuration, a rapid spill can be achieved at the end of an injection process.
  • In the state shown in Figure 2 is the means for injecting fuel in its idle state. The designed as a 2/2-way valve metering valve 6 is set in its closed position. The metering valve 6 can be designed as a directly operated valve or as a servo valve. Furthermore, the metering valve 6 can be actuated both by a magnetic actuator and by a piezoactuator.
  • The hydraulic circuit diagram shown in FIG. 2 shows that the device for injecting fuel comprises a high-pressure reservoir 2 (common rail), which is supplied with fuel via a high-pressure pump (not shown in FIG. 2) which compresses the fuel to a high pressure level , In the high-pressure accumulator 2, which is under system pressure, this is stored so that the fuel system pressure, d. H. the pressure prevailing in the interior of the high-pressure accumulator 2 pressure all fuel injectors 1, which are present in one of the number of cylinders of a self-igniting internal combustion engine corresponding number, can be supplied. The fuel injector 1 comprises the above-mentioned 2/2-way valve metering valve 6, a relief valve 40, received in the control line 20 between the control chamber 11 of the pressure booster 5 and the metering valve 6, the pressure booster 5 and an injection valve member. In the embodiment shown in Figure 2, the pressure booster 5 is formed as an axially displaceable Kobeneinheit, a piston 12 formed by the piston 12, which may be formed integrally or in several parts, a working space 10 and a pressure relief or druckbeaufschlagbarer control chamber eleventh separated from each other. The piston 12 of the pressure booster 5 may comprise a first partial piston 13 and a second partial piston 14. The first sub-piston 13 may be formed in a larger diameter, while the second sub-piston 14 is formed in a contrast reduced diameter and applied to its lower end face a compression space 15 of the pressure booster.
  • From the high pressure accumulator 2, a supply line 9 extends to the working space 10 of the pressure booster 5, wherein in the supply line 9, a throttle point 19 may be formed to attenuate in the supply line 9 forming pressure pulsations or pressure wave reflections and their retroactive effect in the interior of the high-pressure accumulator 2. Im in 2 illustrated rest state of the device for injecting fuel is the metering valve 6, which is preferably designed as a 2/2-way valve, not activated and there is no injection instead. The pressure relief valve 40, received in the control line 20, 49 of the control chamber 11 of the pressure booster 5 is in its open initial state. In the illustrated in Figure 2 switching state of the device for injecting fuel is pending in the interior of the high-pressure accumulator 2 pressure level in the working space 10 of the pressure booster 5, starting from this via an overflow 47 in a second space 42 of the pressure relief valve 40, via a in a valve body 43rd the pressure relief valve 40 formed overflow 44 in a first space 41 of the pressure relief valve 40 at. From the second space 42 of the pressure relief valve 40, the prevailing pressure in the high-pressure reservoir 2 pressure level beyond the control line 20 in the control chamber 11 of the pressure booster 5, of this via the connecting line 25 in a nozzle control chamber 24 in the injector body 4 and a filling line 23 (filling path) is the in the interior of the high pressure accumulator 2 pending pressure in the compression chamber 15 of the pressure booster 5 at.
  • In the idle state of the device for injecting fuel are therefore all the pressure chambers of the pressure booster 5, the working space 10, the control chamber 11 and the compression chamber 15 is acted upon by the pressure prevailing in the high-pressure reservoir 2 pressure level. As a result, the piston 12 of the pressure booster 5 is pressure balanced. The pressure booster 5 is deactivated in the idle state of the device for injecting fuel according to Figure 2 and there is no pressure gain instead. In this state, the piston 12 of the pressure booster 5, which may include a first part piston 13 and a second part piston 14, placed over a arranged in the control chamber 11 return spring element 17 in its initial position, the filling of the compression chamber 15 via the filling line 23, which differs from Nozzle control chamber 24, a check valve 34 containing the compression space 15 extends.
  • By the pending in the nozzle control chamber 24, the pressure level within the high-pressure accumulator 2 corresponding pressure level, a hydraulic closing force is exerted on an end face 27 of the injection valve member 26, which is additionally supported by the closing force of a also recorded in the nozzle control chamber 24 closing spring 28. According to this arrangement, a constant queuing of the prevailing in the high-pressure accumulator 2 pressure levels in the nozzle chamber 22 is possible without the injection valve member 26 unintentionally opens and the injection ports 33 releases to the combustion chamber 7
  • In the position of the piston 12 of the pressure booster 5 shown in FIG. 2, ie in its deactivated state, the compression space 15 of the pressure booster 5 is not is acted upon by the second sub-piston 14 of the piston 12, so that the fuel inlet 21 is acted upon to the nozzle chamber 22 within the injector body 4 of the nozzle body 4 of the fuel injector 1 only with the pressure prevailing in the high-pressure accumulator 2 pressure level This is not sufficient to the injection valve member 26 by generating a hydraulic force at the pressure shoulder 30 to open from its combustion chamber side seat and trigger injection of fuel through the injection ports 33 into the combustion chamber 7 of the self-igniting internal combustion engine.
  • The pressure relief valve 40 integrated in the control line 20, 49 between the metering valve 6 and the control chamber 11 comprises a substantially cylindrically shaped valve body 43. The cylindrical valve body 43 is penetrated by a through-bore 44. The through hole 44 connects the first space 41 with the second space 42 of the pressure relief valve 40. In the position shown in Figure 2 of the valve body 43 of the pressure relief valve 40 whose valve member 45 is released by a slide portion 46 which is retracted into the second space 42. The substantially cylindrical valve body 46 may include a constriction 50. In the first space 41 of the pressure relief valve 40, a valve spring 48 is received, which acts on an upper end face of the valve body 43. By the open slide seat 46 of the valve body 43 of the pressure relief valve 40, the working space 10, the second space 42 of the pressure relief valve 40 via the control line 20 with the control chamber 11 of the pressure booster 5 in conjunction; the same level of pressure prevails in these rooms.
  • FIG. 3 shows the pressure-translating fuel injector according to FIG. 2 in the activated state, that is to say in the activated state. H. with controlled 2/2-way valve.
  • The metering of the fuel is effected by a control of the preferably designed as a 2/2-way valve metering valve 6. This can be controlled either via a piezoelectric actuator or a magnetic actuator; In addition, the metering valve 6 can also be designed as a servo valve or as a directly controlled valve. By controlling the metering valve 6, the first space 41 of the pressure relief valve 40 is connected to the low-pressure side return 8. The valve body 43 of the pressure relief valve 40 closes with its slide portion 46, the valve cross section 45 by retracting against the action of the valve spring 48 in the direction of the first space 41. Thus, the overflow 47 between the working space 10 of the pressure booster 5 and the second space 42 of the pressure relief valve 40th locked. This results in a separation of the control chamber 11 of the pressure booster 5 of the system pressure supply, ie from the high-pressure accumulator chamber 2 (common rail).
  • The pressure relief of the control chamber 11 is now via the control line 20 in the second space 42 of the pressure relief valve 40 and the formed in the valve body 43 through hole 44 in the low-pressure side return 8. By reducing the pressure level in the control chamber 11 of the pressure booster 5 of the pressure booster 5 is activated, since the two-part piston 12 here now moves into the compression space 15 of the pressure booster 5 due to the higher pressure level prevailing in the working space 10. Due to the flow connection between the compression chamber 15 and the nozzle chamber 22 in the nozzle body 4 via the fuel inlet 21, the pressure also increases in the nozzle chamber 22, which surrounds the injection valve member 26 at. Thus, an acting in the opening direction of the injection valve member 26 pressing force on the pressure shoulder 30 of the injection valve member 26 a. At the same time, upon actuation of the metering valve 6, the pressure in the nozzle control chamber 24 is reduced, as a result of which the pressure force acting in the closing direction on the end face 26 of the injection valve member 26 is reduced. The injection valve member 26, which is designed, for example, as a nozzle needle, opens in the nozzle chamber 22 by the hydraulic force applied to the pressure shoulder 30. The opening is thus pressure-controlled, so that fuel flows from the nozzle chamber 22 via the annular gap 32 surrounding the injection valve member 26 in the direction of the tip 31 of the injection valve member 26 flows and passes from there via the injection openings 33 into the combustion chamber 7 of the self-igniting internal combustion engine.
  • As long as the control chamber 11 of the pressure booster 5 remains depressurized, d. H. as long as the pressure booster 5 is activated, there is a very high pressure in its compression space 15. The highly compressed fuel flows from the compression chamber 15 via the fuel inlet 21 to the nozzle chamber 22 and from there via the mentioned annular gap 32 in the direction of the injection openings 33. The by retraction of the piston 12, in the embodiment variant shown in Figure 3 by retraction of the second part piston 14 in the control chamber 11 from this displaced fuel flows via the pressure relief valve 40, d. H. the flow cross-section within the flow channel 44, which passes through the valve body 43 of the pressure relief valve 40 is designed such that a sufficient pressure difference between the first space 41 and the second space 42 of the pressure relief valve 40 sets, the valve body 43 of the pressure relief valve 40 in the closed position, d. H. the sliding portion 46 keeps in overlap with the valve cross-section 45, so that the overflow 47 remains closed in the pressure chamber 10 of the pressure booster.
  • To terminate the injection, the control chamber 11 of the pressure booster 5 is separated from the low-pressure side return 8 by renewed activation of the metering valve 6 designed as a 2/2-way valve and again with the high-pressure reservoir 2 (Common rail) ruling high-pressure level connected. This is done by closing the metering valve designed as a 2/2-way valve 6. The connection to the low-pressure side return 8 is interrupted, whereby the flow of fuel through the flow channel 44 in the valve body 43 of the pressure relief valve 40 comes to a halt This is not effective in the closing direction Pressure difference between the first space 41 and the second space 42 of the pressure relief valve 40 form. By the valve spring 48 arranged in the first space 41, the valve body 43 with its second end face 43 and adjoining slide portion 46 on the valve body 43 is pressed into the second space 42 of the pressure relief valve 40. Thus, the slide portion 46 extends from the valve cross-section 45, so that the pending in the working space 10 of the pressure booster 5, the pressure in the high-pressure accumulator 2 corresponding pressure level on the overflow 47, the second space 42, the control line 20 again at the control chamber 11 of the pressure booster 5 is present , Due to the successful pressure equalization of the piston 12 of the pressure booster 5 moves into the working space 10, wherein its retraction is supported by the arranged in the control chamber 11 return spring element 17. By this retraction, the pressure level within the compression chamber 15 of the pressure booster 5 is lowered rapidly to the pressure prevailing in the high-pressure reservoir 2 pressure level. Since in the nozzle control chamber 24 again the pressure level present in the high-pressure reservoir 2 is present via the connecting line 25, the injection valve member 26 configured as a nozzle needle, for example, is hydraulically balanced, ie the pressure level in the nozzle chamber 22 and in the nozzle control chamber 24 is identical. The closing force, which is exerted by the closing spring element 28 on the end face 27 of the injection valve member 26, outweighs and causes closing of the injection valve member 26, ie its retraction into its combustion chamber side seat. As a result, the injection ports 33 are closed in the region of the tip 31 of the injection valve member 26 and the injection is finished
  • After pressure equalization within the injection system in accordance with the configuration shown in FIG. 3, the pressure booster piston 12 is returned to its initial position by the return spring 17 acting on it. There is a refilling of the compression chamber 15 via the filling line 23 with in this integrated check valve 34 from the nozzle control chamber 24. The compression chamber 15 could also be filled from the hydraulic chambers 11 or 10.
  • The nozzle control chamber 24 in turn is filled via the control chamber 11 of the pressure booster 5 via connecting line 25 with fuel. In the control chamber 11 of the pressure booster 5, in turn, the fuel flows through the working space 10 of the pressure booster 5 via overflow 47, the second space 42 of the pressure relief valve 40 and the control line 20. By refilling, ie the volume compensation in the combustion chamber. 7 via the injection openings 33 at the combustion chamber side seat of the injection valve member 26 injected amount of fuel, the enumerated components are purged and replaced in the combustion chamber 7 of the self-igniting internal combustion engine fuel volume.
  • The metering valve denoted by reference numeral 6 is preferably designed as a 2/2-way valve and can be manufactured particularly easily in the required tolerances manufacturing technology. The preferred as 2/2-way valve metering valve 6 can be performed both as a directly operated valve or as a servo-valve. The control of the 2/2-way metering valve 6 can be done both by a solenoid actuator and piezoelectric actuator. However, it is also possible to use a valve which permits a cross-sectional control of the flow cross section from control line 49 to return 8. The pressure relief valve 40 may advantageously be designed so that no hydraulic pressure surface is present in relation to the pressure prevailing in the overflow line 47. Thus, the valve can be moved by a small spring force and a small pressure difference between the space 42 and the space 41 and only a small throttling of Absteuermenge in the bore 44 is necessary. To optimize the switching behavior, a throttling in the overflow line 47 can also be arranged.
  • In a modification of the structure shown in Figure 3 of the device for injecting fuel into the combustion chamber 7 of a self-igniting internal combustion engine, the nozzle control chamber 24 may be connected instead of the control chamber 11 of the pressure booster 5 via the connecting line 25 with the injector inlet, for example via the working space of the pressure booster. As already mentioned, the piston 12 can be formed within the pressure booster both as a one-part and as a two-part configured component, a first part piston 13 and a second part piston 14 included, which can be formed both one or more parts.
  • FIG. 4 shows the pressure-intensified fuel injector according to the illustration in FIG. 2 with a relief valve with a sealing seat.
  • In contrast to the illustration of the pressure relief valve 40 according to FIGS. 2 and 3, the valve body 43 of the pressure relief valve shown in FIG. 4 comprises a mushroom-shaped shoulder. Instead of a slide portion 45 on the lower end 52 of the valve body 43 with flow channel 44 (see illustration of Figure 3) is at the lower end of the valve body 43 as shown in Figure 4, a mushroom-shaped approach formed, which forms a sealing seat 51 with the valve cross-section 45. An end face 53.1 in the lower region of the valve body 43 is formed in a larger diameter, As the first space 41 of the pressure relief valve 40 opposite end face 52 of the valve body 43. Through the valve body 43 passing through bore 44 can be between the first space 41 and the second space 42 of the pressure relief valve 40 according to the embodiment in Figure 4 reach a pressure difference, which the valve body 43 is held in its closed position when flowing through the flow channel 44, after the designed as a 2/2-way valve metering valve 6 is activated, that is opened. The other components of the fuel injector 1 illustrated in FIG. 4 essentially correspond to the components already described in FIGS. 2 and 3 and will not be explained further in connection with FIG. 4 in order to avoid repetition.
  • FIG. 5 shows the pressure-translated fuel ejector according to the representation in FIG. 2 with a pressure relief valve whose valve body is essentially cylindrical.
  • The device for injecting fuel illustrated in FIG. 5 comprises the fuel injector 1 which contains a metering valve 6 designed as a 2/2-way valve, the pressure booster 5 received in the injector body 3 and the injection valve 26 received in the nozzle body 4. The fuel injector 1 becomes supplied via a high-pressure accumulator 2 (common rail) with fuel under high pressure via the supply line 9 with fuel. The supply line 9 may include a throttle point 19, which serves to dampen pressure pulsations or pressure wave reflections into the interior of the high-pressure fountain space 2, in order to protect it against excessive peak pressure loads. The supply line 9 from the high pressure accumulator 2 (common rail) opens at an outlet point 38 in the working space 10 of the pressure booster 5. The working space 10 and the control chamber 11 of the pressure booster 5 are separated by a piston 12, which has a first part piston 13 and a second Partial piston 14 may include. The piston 12 of the pressure booster 5 may be formed both one or more parts and is acted upon by a arranged in the control chamber 11 spring element 17. The spring element 17 is supported on the one hand on the abutment 16 formed by the bottom of the control chamber 11 and on the other hand on a stop surface 18 in the upper region of the second partial piston 14. The second sub-piston 14 of the piston 12 acts with its lower end face the compression chamber 15 of the pressure booster 5. From the compression chamber 15, the fuel inlet 21 extends to the nozzle chamber 22, which surrounds the injection valve member 26 in the region of a pressure shoulder 30 formed on this From the control chamber 11 of the pressure booster fifth extends a connecting line 25 which opens into the nozzle control chamber 24 of the nozzle body 4 From the nozzle control chamber 24 extends a filling line 23 (filling path) with integrated check valve 34 to the compression chamber 15 of the pressure booster 5, via which the compression space 15th From the nozzle control chamber 24 is filled with fuel. Within the nozzle control chamber 24, a stroke stop 29 is formed, which forms the maximum stroke of the injection valve member 26, for example formed as a nozzle needle, and abuts on the upper end face 27 thereof. Further, a closing spring 28 is received in the nozzle control chamber 24, which acts on the end face 27 of the injection valve member 26. From the nozzle chamber 22 within the nozzle body 4, the annular gap 32, a tapered portion of the injection valve member 26 extends to the tip 31 of the injection valve member 26. In its combustion chamber side seat injection valve member 26 are the injection ports 33, via which the fuel under high pressure is injected into the combustion chamber 7 of the self-igniting internal combustion engine, sealed.
  • From the control chamber 11 of the pressure booster 5, the control line 20 extends to also in this embodiment of the solution proposed by the invention contained pressure relief valve 40. In contrast to the pressure relief valve 40 shown in Figures 2, 3 and 4, the pressure relief valve 40 as shown in Figure 5 is a substantially Cylindrically shaped valve body 54. The cylindrically shaped valve body 54 is penetrated by a flow channel 44 which extends between the first space 41 and the second space 42 of the pressure relief valve 40. The cylindrically shaped valve body 54 moves into the first space 41 with its first end face 52, while the second end face 53 of the cylindrically shaped valve body 54 is associated with the second space 42 of the pressure relief valve 40. In contrast to the embodiments shown in Figures 2, 3 and 4, the overflow line 47 opens between the working space 10 of the pressure booster 5 and the pressure relief valve 40 according to the embodiment of Figure 5 in the first space 41 of the pressure relief valve 40. In the in 5 shows the sealing seat 51, which connects or separates the control chamber 11 of the pressure booster 5 with the working space 10 of the pressure booster, on the side of the Drockentlastungsventiles 40 facing the metering valve 6. The operation of the pressure relief valve shown in Figure 5 40 essentially corresponds to the mode of operation of the device for injecting fuel according to FIG. 2.
  • If the metering valve 6, preferably designed as a 2/2-way valve, opens, closes the pressure relief valve 40. Due to the between the second space 42 and the first space 41 of the pressure relief valve 40 when flowing through the flow channel 44 adjusting pressure difference of cylindrically formed Valve body 54 held when flowing through the flow channel 44 in its closed position. After closing the metering valve 6, however, the pressure relief valve 40 opens, caused by the valve spring 48 arranged in the first space 41 and connects the control chamber 11 of the pressure booster 5 via the control line 20, the second space 42, the flow channel 44 with the first space 41 of the pressure relief valve and from there via the overflow into this overflow 47 with the working space 10 of the pressure booster. As a result, the second part piston 14 moves very quickly out of the compression space 15, the extension being assisted by the return spring 17 arranged in the control space 11. As a result, the pressure in the control chamber 22 falls within the nozzle body 4 very quickly. As a result, the opening force acting on the pressure shoulder 30 of the injection valve member 26 decreases very sharply, so that the injection valve member 26 is pressed into its combustion chamber-side seat via the closing spring 28 arranged in the nozzle control chamber 24, which acts on the end face 27 of the injection valve member 26 and the injection openings 33 in FIG the combustion chamber 7 are closed.
  • LIST OF REFERENCE NUMBERS
  • 1
    fuel injector
    2
    High-pressure storage space (common rail)
    3
    injector
    4
    nozzle body
    5
    Pressure intensifier
    6
    Metering valve (2/2-way valve)
    7
    combustion chamber
    8th
    low-pressure side return
    9
    supply
    10
    working space
    11
    Control room (pressure intensifier)
    12
    piston
    13
    first part piston
    14
    second partial piston
    15
    compression chamber
    16
    abutment
    17
    Return spring
    18
    Return spring stop
    19
    Throttle inlet
    20
    Control line control room
    21
    Fuel inlet nozzle chamber
    22
    nozzle chamber
    23
    Filling line (filling path)
    24
    Nozzle control chamber
    25
    Connecting pipe nozzle control room control room
    26
    Injection valve member
    27
    front
    28
    closing spring
    29
    attack
    30
    pressure shoulder
    31
    top
    32
    annular gap
    33
    Injection ports
    34
    check valve
    35
    filling throttle
    36
    throttle branch
    37
    filling valve
    38
    Mouth point working space
    39
    Mouth point control room
    40
    relief valve
    41
    first room
    42
    second room
    43
    valve body
    44
    flow channel
    45
    Valve cross section
    46
    slide portion
    47
    overflow
    48
    valve spring
    49
    management
    50
    Constriction valve body
    51
    sealing seat
    52
    first end face
    53
    second end face
    53.1
    lower end valve member
    54
    cylindrical valve body

Claims (16)

  1. Device for the injection of fuel into the combustion space (7) of an internal combustion engine, with a high-pressure source (2), with a pressure booster (5) and with a metering valve (6), the pressure booster (5) comprising a working space (10) and a control space (11) which are separated from one another by a movable piston (12; 13, 14), and a pressure change in the control space (11) of the pressure booster (5) resulting in a pressure change in a compression space (15) of the pressure booster (5) which acts via an inflow (21) on a nozzle space (22) surrounding an injection-valve member (26), characterized in that, in a control line (20, 49) between the control space (11) and the pressure booster (5) and a metering valve (6), a pressure relief valve (40) is arranged, with a valve body (43, 54) which acts upon at least one hydraulic space (41, 42) of the pressure relief valve (40), the said hydraulic space being connectable to the pressure prevailing in the high-pressure accumulator space (2),
    - a return (8) located on the low-pressure side extending from the metering valve (6),
    - the control space (11) being connected to the metering valve (6) via a control line (20),
    - with the opening of the metering valve (6) to the return (8) located on the low-pressure side, the valve body (43, 54) closing the connection between the high-pressure source (2) and the control space (11), and
    - with the closing of the metering valve (6), the valve body (43, 54) opening the connection between the high-pressure source (2) and the control space (11).
  2. Device according to Claim 1, characterized in that an overflow line (47) is arranged between the pressure relief valve (40) and the pressure booster (5).
  3. Device according to Claim 2, characterized in that the overflow line (47) issues into the working space (10) of the pressure booster (5).
  4. Device according to Claim 1, characterized in that the valve body (43) of the pressure relief valve (40) has a flow duct (44) which extends essentially parallel to the direction of the control line (20, 49).
  5. Device according to Claim 1, characterized in that the valve body (43) has a slide portion (46) feeding/closing the valve cross section (45) of the pressure relief valve (40).
  6. Device according to Claim 1, characterized in that the valve body (43) has a region (50) of reduced diameter between these end faces (52, 53).
  7. Device according to Claims 2 and 6, characterized in that the overflow line (47) between the pressure booster (5) and the pressure relief valve (40) issues at the latter, on the valve body (43), within the region (50) of reduced diameter.
  8. Device according to Claim 1, characterized in that the valve body (43) of the pressure relief valve (40) is loaded in the opening direction via a valve spring (48).
  9. Device according to Claim 4, characterized in that the flow cross section of the flow duct (44) in the valve body (43, 54) is dimensioned such that a pressure difference of Δp, which keeps the valve body (43, 54) in the closing position, is established between a first space (41) and a second space (42) of the pressure relief valve (40).
  10. Device according to Claim 2, characterized in that the overflow line (47) between the pressure booster (5) and the pressure relief valve (40) issues, at the latter, within a first space (41) which is arranged on that side of the pressure relief valve (40) which points towards the metering valve (6).
  11. Device according to Claim 1, characterized in that the valve body (54) is designed as a cylinder through which a flow duct (44) passes.
  12. Device according to Claim 11, characterized in that one end face (52) of the valve body (54) releases/closes a sealing seat (51) in one of the spaces (41, 42) of the pressure relief valve (40).
  13. Device according to Claims 1, 4 and 9, characterized in that, with the opening of the metering valve (6) to the return (8) located on the low-pressure side, the valve body (43, 54) of the pressure relief valve (40) closes, and the pressure difference Δp established between the first space (41) and the second space (42) via the flow duct (44) keeps the valve body (43, 54) in the closing position.
  14. Device according to Claims 1 and 2, characterized in that, with the closing of the metering valve (6), the valve body (43, 54) of the pressure relief valve (40) opens under spring load, and the control space (11) of the pressure booster (5) is connected via the control line (20), the pressure relief valve (40) and the overflow line (47) to the pressure level prevailing in the high-pressure accumulator space (2) in order to bring about a rapid pressure reduction in the nozzle space (22) of the nozzle body (4).
  15. Device according to Claim 1, characterized in that the compression space (15) of the pressure booster (5) can be filled with fuel via a filling path (23) from the nozzle control space (24) in the nozzle body (4).
  16. Device according to Claim 15, characterized in that a non-return valve (34) is received in the filling path (23) to the compression space (15) of the pressure booster (5).
EP20030722254 2002-06-29 2003-04-03 Boosted fuel injector with rapid pressure reduction at end of injection Expired - Fee Related EP1520099B1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DE10229419 2002-06-29
DE2002129419 DE10229419A1 (en) 2002-06-29 2002-06-29 Pressure-translated fuel injector with rapid pressure reduction at the end of injection
PCT/DE2003/001098 WO2004003376A1 (en) 2002-06-29 2003-04-03 Boosted fuel injector with rapid pressure reduction at end of injection

Publications (2)

Publication Number Publication Date
EP1520099A1 EP1520099A1 (en) 2005-04-06
EP1520099B1 true EP1520099B1 (en) 2006-03-22

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EP20030722254 Expired - Fee Related EP1520099B1 (en) 2002-06-29 2003-04-03 Boosted fuel injector with rapid pressure reduction at end of injection

Country Status (5)

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US (1) US6892703B2 (en)
EP (1) EP1520099B1 (en)
JP (1) JP2005531712A (en)
DE (2) DE10229419A1 (en)
WO (1) WO2004003376A1 (en)

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10229412A1 (en) * 2002-06-29 2004-01-29 Robert Bosch Gmbh Fuel injector with pressure intensifier for multiple injection
WO2004088122A1 (en) * 2003-04-02 2004-10-14 Robert Bosch Gmbh Fuel injector provided with provided with a pressure transmitter controlled by a servo valve
DE10315016A1 (en) 2003-04-02 2004-10-28 Robert Bosch Gmbh Fuel injector with a leak-free servo valve
DE10335340A1 (en) * 2003-08-01 2005-02-24 Robert Bosch Gmbh Control valve for a pressure injector containing fuel injector
JP4196869B2 (en) * 2004-03-31 2008-12-17 三菱ふそうトラック・バス株式会社 Fuel injection device
JP2005315195A (en) * 2004-04-30 2005-11-10 Toyota Motor Corp Fuel injection control method of boosting common rail type fuel injector
DE102004022268A1 (en) * 2004-05-06 2005-12-01 Robert Bosch Gmbh A driving method for influencing the opening speed of a control valve on a fuel injector
DE102004022270A1 (en) * 2004-05-06 2005-12-01 Robert Bosch Gmbh Fuel injector for internal combustion engines with multi-stage control valve
DE102004024527A1 (en) * 2004-05-18 2005-12-15 Robert Bosch Gmbh Fuel injection system
JP3994990B2 (en) * 2004-07-21 2007-10-24 株式会社豊田中央研究所 Fuel injection device
JP4075894B2 (en) * 2004-09-24 2008-04-16 トヨタ自動車株式会社 Fuel injection device
DE102005030220A1 (en) * 2005-06-29 2007-01-04 Robert Bosch Gmbh Injector with switchable pressure intensifier
JP4695453B2 (en) * 2005-07-29 2011-06-08 株式会社デンソー Directional control valve
US7464697B2 (en) * 2005-08-19 2008-12-16 The United States Of America, As Represented By The Administrator Of The U.S. Environmental Protection Agency High-pressure fuel intensifier system
DE102007001363A1 (en) * 2007-01-09 2008-07-10 Robert Bosch Gmbh Injector for injecting fuel into combustion chambers of internal combustion engines
JP4600405B2 (en) * 2007-03-08 2010-12-15 株式会社デンソー Injector
US20100096473A1 (en) * 2008-10-20 2010-04-22 Caterpillar Inc. Variable flow rate valve for mechnically actuated fuel injector
JP6384366B2 (en) * 2015-03-09 2018-09-05 株式会社デンソー Fuel injection device
EP3550136A1 (en) 2016-12-02 2019-10-09 Meiji University Fuel injection device

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6259230B2 (en) * 1981-01-24 1987-12-10 Diesel Kiki Co
JPS6249459B2 (en) * 1981-01-24 1987-10-20 Diesel Kiki Co
JP2885076B2 (en) 1994-07-08 1999-04-19 三菱自動車工業株式会社 Accumulator type fuel injection device
DE19939423A1 (en) * 1999-08-20 2001-03-01 Bosch Gmbh Robert Fuel injection system for an internal combustion engine
DE19939429A1 (en) * 1999-08-20 2001-03-01 Bosch Gmbh Robert Fuel injector
DE19945785B4 (en) * 1999-09-24 2010-10-07 Robert Bosch Gmbh Fuel injection system for internal combustion engines and method for injecting fuel into the combustion chamber of an internal combustion engine
DE19952512A1 (en) * 1999-10-30 2001-05-10 Bosch Gmbh Robert Pressure booster and fuel injection system with a pressure booster
DE10040526A1 (en) * 2000-08-18 2002-03-14 Bosch Gmbh Robert Fuel injection system
DE10060089A1 (en) * 2000-12-02 2002-06-20 Bosch Gmbh Robert Fuel injection system

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DE50302741D1 (en) 2006-05-11
US20040231645A1 (en) 2004-11-25
US6892703B2 (en) 2005-05-17
JP2005531712A (en) 2005-10-20
DE10229419A1 (en) 2004-01-29
EP1520099A1 (en) 2005-04-06
WO2004003376A1 (en) 2004-01-08

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