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
  • F02M47/025—Hydraulically 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
  • 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
  • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
  • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
• • 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
  • F02M63/0029—Valves characterised by the valve actuating means hydraulic using a pilot valve controlling a hydraulic chamber
• • 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
  • F02M63/02—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
  • F02M63/0225—Fuel-injection apparatus having a common rail feeding several injectors ; Means for varying pressure in common rails; Pumps feeding common rails
• • 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
  • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
  • F02M2200/70—Linkage between actuator and actuated element, e.g. between piezoelectric actuator and needle valve or pump plunger
  • F02M2200/703—Linkage between actuator and actuated element, e.g. between piezoelectric actuator and needle valve or pump plunger 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
  • F02M2547/00—Special features for fuel-injection valves actuated by fluid pressure
  • F02M2547/001—Control chambers formed by movable sleeves

Definitions

• the invention relates to a fuel injection device for an internal combustion engine with direct fuel injection according to the preamble of claim 1.
• a valve element is arranged in a housing, which in the region of a fuel outlet opening has a total acting in the opening direction of the valve element pressure surface.
• a control surface acting in the closing direction is present, which delimits a control chamber.
• the control surface acting in the closing direction is larger than the pressure surface acting in the opening direction when the valve element is open.
• a prerequisite for the operation of this fuel injection device is a seal between that region in which the comparatively small pressure acting in the opening direction pressure surface is present, and that region of the valve element in which the comparatively large acting in the closing direction control surface is present.
• Leakage fluid is discharged in the known fuel injection device from the region of the seal via a leakage line.
• Object of the present invention is to develop a fuel injection device of the type mentioned so that it is as simple and inexpensive builds and can be used at a very high operating pressure.
• the freedom of design of the fuel injection device is significantly increased by the hydraulic coupling of two separate parts of the valve element, because it can the respective parts of the valve element respectively optimally adjust the location within the fuel injector.
• the elastic properties of the valve element can be optimally adapted to the intended area of use by an appropriate choice of the material used and the dimensions.
• the manufacture of the valve element as a whole is considerably simplified, since it is also possible to use parts of constant diameter. This allows a simpler structure of the fuel injection device with simpler parts, which on the one hand facilitates the production and on the other hand allows a smaller design.
• numerous components of previous devices can continue to be used for realizing the present invention.
• Another advantage of the hydraulic coupler is the compensation of tolerances, which simplifies the manufacture and assembly.
• the coupling of two parts of the valve element by means of a hydraulic coupler also allows the realization of a certain motion damping.
• the hydraulic coupler can be realized very easily.
• valve element Surrounding the valve element during operation at least temporarily and at least approximately prevails at the high-pressure connection high fuel pressure prevails (the valve element "floats" in the high pressure), and when the valve element has a closing in the direction acting hydraulic control surface and acting in the opening direction hydraulic pressure surface. This means nothing else than that in such a device on the valve element between the pressure surface and the control surface a previously required pressure level is no longer present.
• a high pressure "floating" Valve element can be realized, for example, that the recess in which the valve element is received in total, is connected to the high-pressure port.
• the fuel injection device according to the invention operates with a high efficiency, since the existing in earlier devices leakage between the valve element and the housing is no longer available. A return line can be made smaller in the sequence.
• valve element is pressure balanced overall with correspondingly high dynamics.
• the force excess required in the closing direction in the closing direction can be realized in this case by a slight throttling in the area of the pressure surface, and / or by a throttling of the fuel flow reaching the pressure surface.
• the assembly of the fuel injection device is simplified if the valve element is accommodated in total in a high-pressure connection connected to the high-pressure port. This can also work as a damping volume, are reduced by which pressure waves and consequent wear on a valve seat. In addition, the accuracy of injection quantities increases with multiple injection. In addition, the production is simplified, since a separate high-pressure bore for connecting the pressure chamber to the high pressure port can be omitted.
• Figure 1 is a schematic representation of a
• Figure 2 is a schematic and partially sectioned view of a first embodiment of the fuel injection device of Figure 1;
• Figure 3 is a view similar to Figure 2 of a second embodiment
• Figure 4 is a view similar to Figure 2 of a third embodiment
• Figure 5 is a view similar to Figure 2 of a fourth embodiment
• Figure 6 is a view similar to Figure 2 of a fifth embodiment
• Figure 7 is a representation similar to Figure 2 of a sixth
• Figure 8 is a view similar to Figure 2 of a seventh
• FIG. 9 shows a section of FIG. 8 designated by IX in a spatial representation.
• an internal combustion engine carries a total of the reference numeral 10. It is used to drive a motor vehicle, not shown.
• a high-pressure conveyor 12 conveys fuel from a fuel reservoir 14 into a fuel pressure accumulator 16 ("rail"). In this fuel - diesel or gasoline - is stored under very high pressure.
• To the rail 16 are by means of each a high pressure port 17 a plurality of fuel injectors 18 are connected, which inject the fuel directly into them associated combustion chambers 20.
• the fuel injection devices 18 each also have a low-pressure connection 21, via which they are connected to a low-pressure region, in the present case to the fuel reservoir 14.
• the fuel injection device 18 may be formed in a first embodiment according to Figure 2:
• the fuel injection device 18 shown therein comprises a housing 22 having a nozzle body 24, a main body 26 and an end body 28.
• a stepped recess 30 is present, in which a needle-like valve element 32 is received. This is formed in two parts with a control piston 34 and a nozzle needle 36.
• the nozzle needle 36 has at its lower end in Figure 2, a conical pressure surface 38 a, which limits a pressure chamber 40.
• the nozzle needle 36 operates in the region of the pressure surface 38a in a manner not shown in Figure 2 with a housing-side valve seat together. In this way, fuel outlet openings 42 are separated from the pressure chamber 40 or connected thereto.
• the nozzle needle 36 when the nozzle needle 36 abuts the pressure surface 38a on the housing-side valve seat, only one lying upstream of the valve seat portion of the pressure surface 38a is acted upon by the pressure prevailing in the pressure chamber 40 pressure. Only then, when the nozzle needle 36 lifts off the valve seat, is located at a downstream of the valve seat area of the pressure surface 38a to an increased pressure. However, this is not shown in the figure for reasons of clarity.
• the nozzle needle 36 has a smaller diameter portion 44 and a larger diameter portion 46. Between these there is a shoulder, which also forms a pressure surface acting in the opening direction of the valve element 32, which bears the reference numeral 38b. With the section 46, the nozzle needle 36 is guided longitudinally displaceable in the nozzle body 24.
• the control piston 34 is guided in the main body 26. Its lower end is enough with one in the present
• An upper axial end face 51 of the nozzle needle 36 protrudes into the coupling space 50.
• the upper end of the control piston 34 extends into an enlarged region of the recess 30, so that in this area between the valve element 32 and the wall of the recess 30, an annular space 52 is formed.
• a sleeve 54 is pushed, which is pressed by a spring 55 which is supported via an annular collar 56 on the control piston 34, with a sealing edge (without reference numeral) against the end body 28.
• the upper axial end face of the control piston 34 in FIG. 2 forms a hydraulic control surface 58 acting in the closing direction of the valve element 32. It delimits, together with the sleeve 54 and the end body 28, a control chamber 60. This is via an inlet throttle 62 provided in the sleeve 54 is connected to the annulus 52. Furthermore, the control chamber 60 is connected by a combined inlet and outlet throttle 64, which is present in the end body 28, with a 3/2-way switching valve 66. Depending on the switching position this connects the inlet and Outlet throttle 64 either with the high pressure port 17 or with the low pressure port 21.
• the annular space 52 is also constantly via a channel 68 with the
• High-pressure port 17 connected as the pressure chamber 40 via a channel 70th
• the portion 46 of the nozzle needle 36 has the same diameter Dl as the control piston 34 (diameter D2 and D3). It also follows that the two pressure surfaces 38a (upstream and downstream of the valve seat) and 38b, projected onto a plane perpendicular to the longitudinal axis of the valve element 32, in sum form the same hydraulically effective area as the control surface 58 when the valve element is lifted off the valve seat.
• the fuel injection device 18 shown in Figure 2 operates as follows: In the initial state, with de-energized switching valve 66, the control chamber 60 via the combined inlet and outlet throttle 64 and the inlet throttle 62 to the high pressure port 17 and thus connected to the rail 16. In the control chamber 60 thus prevails the high rail pressure. This prevails over the channel 68 also in the annular space 52 and via the channel 70 in the pressure chamber 40. Due to certain unavoidable leaks through the leadership of the nozzle needle 36 in the nozzle body 24 and the control piston 34 in the main body 26 also prevails in the coupling space 50 rail pressure.
• High pressure port 17 is interrupted and this instead connected to the low pressure port 21. Due to the throttle effect of the combined inlet and outlet throttle 64 and the inlet throttle 62, the pressure in the control chamber 60 decreases.
• Annular space 52, the channel 70 and the pressure chamber 40 are injected via the fuel outlet openings 42 into the combustion chamber 20.
• the switching valve 66 is returned to its closed position, in which the inlet and outlet throttle 64 is connected to the high pressure port 17.
• the pressure in the control chamber 60 now rises again to rail pressure.
• the control piston 34 is stopped and moved back in the closing direction, since the pressure in the coupling chamber 50 is initially lower than in the control chamber 60.
• the pressure in the coupling chamber 50 increases due to the reduction in volume up to rail pressure.
• control piston 34 has the same diameter D2 as the portion 46 of the nozzle needle (diameter Dl)
• the control piston 34 is only now again with the end surface 48 on the end face 51 of the nozzle needle 36.
• Valve element 32 hydraulically assisted. As soon as the nozzle needle 36 rests again on the valve seat in the area of the fuel outlet openings 42, the injection is ended.
• the nozzle needle 36 is hydraulically coupled to the control piston 34 through the coupling space 50.
• the end face 48, the coupling space 50 and the end face 51 so far form a total of a hydraulic coupler 71.
• the valve element 32 surrounding spaces available are, in which at least temporarily and at least in about the high-pressure port 17 or in the rail 16 adjacent high rail pressure prevails. The valve element 32 thus "floats" in fuel at high pressure.
• FIG. 3 shows an alternative embodiment of a fuel injection device 18.
• elements and regions which have equivalent functions to previously described elements and regions bear the same reference numerals and are not explained again in detail. For simplicity, not all reference numerals are also entered.
• the switching valve 66 is executed in the fuel injection device shown in Figure 3 as a 2/2-way valve.
• the control chamber 60 can be connected via the device formed in this case only as a drain throttle 64 either with the low pressure port 21 or separated from it.
• the channel 70 which the switching valve 66 is executed in the fuel injection device shown in Figure 3 as a 2/2-way valve.
• a throttle 72 is provided.
• the pressure in the pressure chamber 40 is slightly below the rail pressure when the valve element 32 is open. In this way, the closing operation of the valve element 32 is simplified or accelerated.
• the throttle 72 may be disposed elsewhere between the high-pressure port 17 and the pressure chamber 40, for example in the channel 68th
• the diameter D2 and D3 of the control piston 34 are larger than the diameter Dl of the portion 46 of the nozzle needle 36. This has the consequence that during the opening process, ie with open switching valve 66, the pressure in the coupling chamber 50 decreases and the nozzle needle 36 very quickly back into abutment reaches the control piston 34. In addition, this is tensioned in the opening stroke of the valve element 32 by the hydraulic coupler 71 acting in the closing direction on the control piston 34 "hydraulic spring", which supports the subsequent closing operation even when in the open state in itself pressure balanced valve element 32.
• the coupling space 50 is not formed between valve element 32 and housing 22, but between valve element 32 and an additional sleeve 74. This is acted upon by a spring 76, which is supported on the main body 26, against the nozzle body 24.
• the control piston 34 in Figure 5 above the annular collar 56 has a larger one
• the sleeve 74 allows for a significant increase in the annulus 52, which simplifies the manufacture and configuration of the main body 26.
• the increased volume of the annulus 52 provides for improved damping characteristics, for example for damping pressure waves.
• the sleeve 54 is integral with the end body 28.
• a fifth embodiment of the fuel injection device is shown, which is substantially the same as in the embodiments according to Figures 2 to 5, but the control piston 34 as the nozzle needle 36 is guided in the nozzle body 24 and not in the main body 26.
• This has the advantage that the guides for the nozzle needle 36 and the control piston 34, which are formed by a bore 25 in the nozzle body 24, with high accuracy can be made.
• the diameter Dl of the nozzle needle 36 and the diameter D2 of the control piston 34 may be the same or different, whereby the volume of the coupling space 50 can be varied.
• the volume of the coupling space 50 can likewise be varied, as a result of which the behavior of the coupler 71 can be influenced.
• FIG. 7 shows a sixth embodiment of the fuel injection device is shown, in which the basic structure is the same as in the embodiment of Figure 5, but in which an additional throttle 86 is provided, which is arranged in the connection of the pressure chamber 40 with the high-pressure port 17 is.
• the additional throttle 86 is arranged in a leading to the pressure chamber 40 branching of the channel 68, wherein the channel 68 upstream of the additional throttle 86, the compound discharges into the control chamber 60, in which
• Inlet throttle 62 is arranged. Between the sleeve 54 and the main body 26 while a sealing element 86 is arranged, through which the annular space 52 is divided into two separate annulus areas 52a and 52b. The connection to the control room 60 leads through the
• annular space 52 is separated into two separate ones by a sealing element 87 clamped between the main body 26 and the sleeve 54
• Annular space regions 52a and 52b is divided.
• the control piston 34 has an enlarged diameter D4 at its end arranged in the sleeve 54, via which the control piston 34 is guided in the sleeve 54.
• the high-pressure connection 17 opens into the annular space region 52a, from which the connection leads into the control chamber 60 with the inlet throttle 62.
• FIG. 9 shows a further embodiment of the fuel injection device, which is suitable in particular for the embodiment according to FIG. 8 but also for all other embodiments explained above.
• the sleeve 54 is shown in which the control piston 34 is guided with its enlarged diameter end.
• the inlet throttle 62 is formed by several, for example, about 4 to 9, in diameter very small holes 63, which are preferably introduced by laser drilling into the sleeve 54.
• the holes 63 are arranged distributed over the circumference of the sleeve 54 and the
• Diameter of the holes 63 may be about 0.1 mm.
• the inlet and / or outlet region of the bores 63 may be rounded, for example by means of a hydroerosive method.
• the holes 63 have in addition to the throttle function and the function of a filter, so that an additional filter in the region of the high-pressure port 17 may optionally be omitted. Clogging of the inlet throttle 62 is unlikely because of the multiple holes 63.
• the additional throttle 86 in the connection to the pressure chamber 40 may be formed by a plurality of bores 88 with a small diameter in the sleeve 54, as shown in Figure 9.
• To form the throttle 86 for example, about 20 to 50 holes 88 may be provided, each of which may have a diameter of about 0.1 mm.
• the holes 88 are distributed over the circumference of the sleeve 54.
• FIG. 9 also shows the sealing element 87, by which the two annulus areas 52a and 52b according to FIG. 8 are separated from one another.

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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)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)

Applications Claiming Priority (3)

Publications (2)

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Family Applications (1)

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• 2006
  • 2006-03-02 DE DE102006009659A patent/DE102006009659A1/de not_active Withdrawn
  • 2006-05-31 JP JP2008523271A patent/JP4714268B2/ja not_active Expired - Fee Related
  • 2006-05-31 WO PCT/EP2006/062779 patent/WO2007012510A1/fr active Application Filing
  • 2006-05-31 KR KR1020087001875A patent/KR101092762B1/ko active IP Right Grant
  • 2006-05-31 EP EP06777252A patent/EP1910663B1/fr active Active
  • 2006-05-31 BR BRPI0613995A patent/BRPI0613995B1/pt not_active IP Right Cessation
  • 2006-05-31 CN CN200680027271XA patent/CN101228347B/zh active Active
  • 2006-05-31 DE DE502006006260T patent/DE502006006260D1/de active Active
  • 2006-05-31 AT AT06777252T patent/ATE458909T1/de active
  • 2006-05-31 US US11/996,558 patent/US8136741B2/en not_active Expired - Fee Related

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