Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M47/00—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure
  • F02M47/02—Fuel-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
  • F02M47/027—Electrically actuated valves draining the chamber to release the closing pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M47/00—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure
  • F02M47/02—Fuel-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
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
  • F02M55/02—Conduits between injection pumps and injectors, e.g. conduits between pump and common-rail or conduits between common-rail and injectors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
  • F02M59/02—Pumps 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
  • F02M59/10—Pumps 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
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
  • F02M59/02—Pumps 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
  • F02M59/10—Pumps 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
  • F02M59/105—Pumps 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
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
  • F02M63/0012—Valves
  • F02M63/0014—Valves characterised by the valve actuating means
  • F02M63/0015—Valves characterised by the valve actuating means electrical, e.g. using solenoid
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
  • F02M63/0012—Valves
  • F02M63/0014—Valves characterised by the valve actuating means
  • F02M63/0028—Valves characterised by the valve actuating means hydraulic
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
  • F02M63/0012—Valves
  • F02M63/0031—Valves characterized by the type of valves, e.g. special valve member details, valve seat details, valve housing details
  • F02M63/0049—Combined valve units, e.g. for controlling pumping chamber and injection valve

Definitions

• the invention relates to a fuel injector for injecting in a fuel storage under high pressure held fuel into the combustion chamber of an internal combustion engine according to the preamble of claim 1.
• a pressure-intensified fuel injector which contains a hydraulic pressure booster piston, which communicates with the injection nozzle communicating delivery volume with a first, smaller cross section and an optionally acted upon by the fuel pressure working volume with a second, larger cross section having.
• the working volume is by an electrically controlled 3/2 -way valve either to trigger the power stroke with the fuel pressure of the stored in the fuel tank under high pressure fuel or Return of the pressure booster piston to its original position for pressure relief with a leakage line connectable.
• the electrically actuated control valve means additional effort and requires its own electrical control.
• Another pressure-translated fuel injector is known from DE 100 60 089 A1.
• the control of a pressure booster piston which is constructed similar to the previously described known pressure-translated Kraftstoffinj ector, by depressurizing a differential space, which corresponds to the difference of the cross sections of working volume and flow, via an electrically controlled 2/2-way valve.
• a pressure-intensified fuel injector is known to be known, in which for the control of the differential space of the pressure booster piston with low pressure or the fuel pressure can be applied.
• the control piston coupled to the nozzle needle has a dual function. Depending on the position of the control piston, which forms a slide valve, a line leading to the differential space is connected to low pressure or the low pressure connection is blocked. In the blocking position, the differential space is acted upon by another, throttled line connection to the fuel pressure.
• the object of the invention is to provide an improved fuel injector of the presumed kind.
• a pressurized Kraftstoffinj is to be created ector, which is controlled with little effort and ensures reliable operation.
• the object is achieved by a fuel injector with the features of claim 1.
• the invention provides a fuel injector for injecting fuel stored in a fuel reservoir under high pressure into the combustion chamber of an internal combustion engine under at least two different injection pressures, comprising an injector housing, a longitudinally displaceably arranged nozzle needle in the housing and an injector nozzle to be selectively opened by the nozzle needle , by which the fuel is injectable into the combustion chamber of the internal combustion engine, a cooperating with the nozzle needle, acted upon by the fuel pressure control chamber which is depressurable in the sense of opening the injector by means of a first control valve and a pressure booster for conveying fuel to be injected under elevated pressure, said the pressure booster is controllable by a second control valve which is hydraulically connected to the control chamber for actuation by the pressure of the fuel in the control chamber.
• the second control valve (8) is designed as a 3/2-way valve which has a valve body (8a) acted upon by a fuel pressure prevailing in the control chamber (12) on a control piston surface (8b).
• the fuel injector according to the invention is advantageously suitable for injecting fuel, in particular also of heavy oil into the combustion chamber of an internal combustion engine with different pressure levels, in particular for a pre- and / or post-injection of fuel with the pressure in the fuel reservoir (common rail) below high pressure held fuel, as well as for a main injection with a maximum pressure caused by the pressure booster.
• valve body of the control valve is expediently acted upon with a delay in time with the fuel pressure prevailing in the control chamber.
• a pre-injection and post-injection and the beginning of the main injection at a lower pressure level than the main injection is possible, since the pressure ratio responds with a time delay.
• the pressure booster comprises a pressure booster piston having at its front a communicating with the injection nozzle, a first, smaller cross-section having promotional volume and on its back a second, larger cross-section having working volume , wherein the working volume via the second control valve in the sense of conveying fuel through the pressure booster piston under increased pressure optionally acted upon with the fuel pressure.
• the pressure booster includes a pressure booster piston having at its front a communicating with the injection nozzle, a first, smaller cross-section having promotional volume and on its back a second, larger cross-section having working volume in which a differential volume, which has a third cross section and which corresponds to a difference between the cross sections of the working volume and delivery volume and which is still present on the front side of the pressure booster piston, is conveyed via the second control valve in the sense of Conveying fuel through the pressure booster piston under elevated pressure is optionally pressure relieved.
• control valve (8) connects a line leading from the control valve (18) to the pressure booster piston (9) either with a leakage line (3) or with a fuel line (15) in communication with the fuel reservoir (1).
• control piston surface is coupled via a line connection to the control chamber, which contains a throttle which determines the temporal response of the second control valve.
• the throttle is connected in parallel in the flow direction from the control chamber to the control piston surface of the second control valve non-return valve.
• temporal response of the second control valve is dimensioned such that at a short pressure relief of the control chamber for a pre-injection and / or post-injection of fuel with non-elevated pressure release of the injector without effective control of the pressure booster and at a longer pressure relief of the control chamber for a main injection of fuel with increased pressure, a release of the nozzle needle with effective control of the pressure booster takes place.
• Figure 1 is a schematic representation of a pressure translated Kraftstoffinj injector according to an embodiment of the invention
• FIG. 1 shows a fuel injector which is provided for injecting fuel stored in a fuel reservoir 1 (common rail) under high pressure.
• the fuel injector comprises an injector housing 11, which is shown only partially, in which a nozzle needle 6 is arranged so as to be displaceable in the longitudinal direction and selectively releases an injection nozzle 7 provided at its front end for injecting the fuel.
• a control chamber 12 is provided, which is acted upon by an inlet throttle 4 of the fuel stored in the fuel tank 1 under high pressure fuel and a first control valve 2 is optionally pressure relieved.
• the held in the fuel tank 1 under high pressure fuel is a tip of the nozzle needle 6 annularly surrounding the nozzle front chamber 14 via a fuel passage 15.
• Rothbar contains the fuel injector a Druckbergerset ⁇ zer 19, which comprises a pressure transmission piston 9, a first, smaller cross section exhibiting Air flow 16 is provided and on its rear side a second, larger cross section exhibiting the working volume 17 at the front thereof.
• the delivery volume 16 of the pressure booster piston 9 is also connected in the course of the fuel passage 15 to the nozzle front chamber 14, wherein upstream of the delivery volume 16 in the fuel passage 15 is a check valve 10 which prevents a return flow of fuel from the delivery volume 16 to the upstream.
• a further provided second control valve 8 is provided in the form of a 3/2 -way valve, which connects the provided at the rear of the pressure booster piston 9 working volume 17 optionally with the fuel passage 15 or depressurized via a leakage line 3.
• the second control valve 8 includes a valve body 8a, on which a control piston surface 8b is provided, which is acted upon via a control line 12a of the pressure prevailing in the control chamber 12 fuel pressure.
• a control piston surface 8b fuel pressure of the control chamber 12
• the valve body 8a of the second control valve 8 is forced to a first, closed position in which an influx of the high-pressure fuel from the fuel passage 15 to-working volume 17 of the pressure booster piston 9 locked and on the other hand, the connection of the working volume 17 is released to the leakage line 3.
• a throttle 5 is arranged, through which the temporal response of the second control valve 8 to pressure changes in the control chamber 12 in response to opening and closing of the first control valve 2 is determined.
• This throttle 5 is a check valve 5a connected in parallel, which is continuous in the direction of the control chamber 12 to the control piston surface 8b.
• the pressure booster 19 is thus controlled in response to the pressure prevailing in the control chamber 12 pressure by the second Steuerven ⁇ til 8.
• FIG. 2a shows the initial state in which the first control valve 12 is not actuated electromagnetically.
• the nozzle needle 6 keeps the injection nozzle 7 closed and the second control valve 8 is in the closed position shown in Figure 1, in which the working volume 17 of the pressure booster piston 9 is shut off from the voltage applied in the fuel passage 15 fuel pressure and instead connected to the leakage line 3 ,
• the first control valve 2 is now actuated electromagnetically and causes a pressure drop in the control chamber 12 above the nozzle needle 6, which leads to the opening of the injection nozzle 7.
• the fuel present in the nozzle front chamber 14 at the tip of the nozzle needle 6 is injected into the combustion chamber of the internal combustion engine under the pressure supplied by the fuel reservoir 1.
• the second control valve 8 is not yet actuated, that is, the pressure drop caused by the opening of the first control valve 2 in the control chamber 12 does not yet arrive at the control piston surface 8b of the valve body 8a of the second control valve 8 Effect.
• the first control valve 2 is closed by the end of the energization, whereby a re-increase of the pressure of the control chamber 12 is accompanied by subsequent flow of fuel from the fuel channel 15 via the inlet throttle 4.
• This increase in the fuel pressure in the control chamber 12 is planted via the throttle 5 located in the control line 12a after a short time Time to the control piston surface 8b on the valve body 8a of the second control valve 8 on, so that this closed and the working volume 17 of the pressure booster piston 9 is separated from the fuel passage 15.
• the second control valve 8 opens the flow of the working volume 17 to the leakage line 3, whereby the pressure booster piston 9 is returned to its initial position.
• the pressure drop occurring in the nozzle antechamber 14 causes a closing of the nozzle needle 6 and thus an end of the injection process.
• Figures 3a) to f) show the time course of various pressures on Kraftstoffinj ector and piston movement and injection rate during the phases described with reference to Figures 2a) to d) during the injection process.
• FIG. 3 a shows the time-constant pressure in the fuel accumulator 1, that is to say the pressure of the common rail.
• FIG. 3b) shows the pressure in the control chamber 12 at the rear side of the nozzle needle 6.
• FIG. 3c shows the pressure on the control piston surface 8b of the valve body 8a of the second control valve 8.
• FIG. 3d shows the movement of the pressure booster piston 9.
• FIG. 3 e shows the pressure in the nozzle front chamber 14 in front of the injection nozzle 7.
• FIG. 3f shows the course of the injection rate of the fuel injected by the injection nozzle 7 into the combustion chamber of the internal combustion engine.
• a post-injection is effected at low pressure, similar to the pre-injection described above.
• Fuel reservoir First control valve (common rail) Leakage line Inlet restrictor Throttle a Check valve Nozzle needle Injector second control valve a Valve body b Spool area Pressure transfer piston 0 Check valve 1 Injector housing 2 Control chamber 2a Control line 3 Spring 4 Nozzle vestibule 5 Fuel channel 6 Delivery volume 7 Working volume 8 Differential volume 9 Compressor

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Fuel-Injection Apparatus (AREA)

Applications Claiming Priority (2)

Publications (2)

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ID=36993341

Family Applications (1)

Country Status (6)

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Family Cites Families (5)

• 2005
  • 2005-07-15 DE DE102005033123A patent/DE102005033123B3/de not_active Expired - Fee Related
• 2006
  • 2006-07-12 WO PCT/EP2006/006796 patent/WO2007009641A1/fr active Application Filing
  • 2006-07-12 AT AT06762543T patent/ATE431901T1/de active
  • 2006-07-12 KR KR1020077030330A patent/KR101001002B1/ko not_active IP Right Cessation
  • 2006-07-12 EP EP06762543A patent/EP1907686B1/fr not_active Not-in-force
  • 2006-07-12 JP JP2008520786A patent/JP4869342B2/ja not_active Expired - Fee Related
  • 2006-07-12 DE DE502006003778T patent/DE502006003778D1/de active Active

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