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
  • F02M47/06—Other fuel injectors peculiar thereto
• • 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
  • F02M63/004—Sliding valves, e.g. spool valves, i.e. whereby the closing member has a sliding movement along a seat for opening and closing
  • F02M63/0042—Sliding valves, e.g. spool valves, i.e. whereby the closing member has a sliding movement along a seat for opening and closing combined with valve seats of the lift valve type
• • 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
  • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
  • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
  • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
• • 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
  • F02M63/0003—Fuel-injection apparatus having a cyclically-operated valve for connecting a pressure source, e.g. constant pressure pump or accumulator, to an injection valve held closed mechanically, e.g. by springs, and automatically opened by fuel 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
  • 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
  • F02M63/0003—Fuel-injection apparatus having a cyclically-operated valve for connecting a pressure source, e.g. constant pressure pump or accumulator, to an injection valve held closed mechanically, e.g. by springs, and automatically opened by fuel pressure
  • F02M63/0005—Fuel-injection apparatus having a cyclically-operated valve for connecting a pressure source, e.g. constant pressure pump or accumulator, to an injection valve held closed mechanically, e.g. by springs, and automatically opened by fuel pressure using valves actuated by fluid 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
  • 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
  • F02M63/0003—Fuel-injection apparatus having a cyclically-operated valve for connecting a pressure source, e.g. constant pressure pump or accumulator, to an injection valve held closed mechanically, e.g. by springs, and automatically opened by fuel pressure
  • F02M63/0007—Fuel-injection apparatus having a cyclically-operated valve for connecting a pressure source, e.g. constant pressure pump or accumulator, to an injection valve held closed mechanically, e.g. by springs, and automatically opened by fuel pressure using electrically actuated valves
• • 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
  • F02M63/0047—Four-way valves or valves with more than four ways

Definitions

• the invention relates to a double-switching high pressure injector, the z. B. is provided for injecting fuel under high pressure into the combustion chambers of a combustion engine.
• pre-injection phases or post-injection phases may be required on direct-injection internal combustion machines with a large displacement.
• the pre-injection phase or the post-injection phase places high demands on the accuracy of the controllability of a control part which controls the injection phases in an injector housing, in particular on its manufacturing tolerances, in order to implement the specified injection profiles.
• the control valve member consists of a valve stem, which forms a guide sleeve and slides into a channel, and a valve head connected to it and facing the actuating device.
• the sealing surface of the valve head interacts with a surface of the control bore that forms the valve seat.
• the circumference of the valve stem has a recess, the axial extent of which extends from the confluence of the fuel supply line to the beginning of the sealing surface on the valve head which interacts with the valve seat.
• a surface exposed to the pressure of the fuel supply line is formed in the recess and is equal to a surface of the valve head exposed to the pressure of the fuel supply line in the closed state of the control valve.
• a main injection phase and a pre-injection phase for example for injecting fuel into the combustion chambers of an internal combustion engine, are possible when using an externally actuatable actuator which realizes two switching positions of the control part. Since there is no need for balistic operation of the control part, the control part can be manufactured much more precisely in terms of its guide and seat diameters.
• valve chamber which can be supplied with fuel under high pressure via a high-pressure plenum inlet (common rail inlet), can be used as a throttle gap if the ratio of the valve chamber diameter to the control valve to diameter is appropriately interpreted.
• the nozzle system When using an actuator providing the control part in two switching stages, i. H. when the control part is switched through as in the case of a centrally positioned control part, the nozzle system is relieved of the fuel under high pressure by means of control elements arranged on one and the same control part.
• the injection nozzle system in particular the nozzle inlet and the nozzle chamber that surrounds the nozzle needle, is relieved of the fuel under high pressure, which considerably reduces the mechanical stress on these components and considerably extends the service life of the injector that realizes two states of a control surface.
• the control part of the injector proposed according to the invention can be designed to be force-balanced since all the guide and seat diameters have the same diameter. Unevenly distributed mechanical loads on the control part are thus avoided.
• the leakage oil flow into the leakage oil line of the housing of the injector proposed according to the invention can be limited, so that the efficiency of the invention according to the proposed multi-stage switching injector is not affected negatively '. drawing
• FIG 1 shows the longitudinal section through the injector proposed according to the invention and realizing different injection phases
• Fig. 2 is an enlarged view of the valve chamber on the control part of the injector and
• Fig. 3 shows the time courses of the control valve stroke or the injection phases, each plotted over the time axis.
• FIG. 1 shows the illustration of a longitudinal section through the injector proposed according to the invention and realizing different injection phases for high-pressure collecting space (common rail) use.
• a control part 4 is accommodated in the housing 2 of the injector 1, a bore 3 which extends essentially in the vertical direction.
• the control part 1 can be moved up and down in the bore 3 of the housing 2 by means of an actuator, not shown here, which realizes several switching states, for example an electromagnet, a piezo actuator or a mechanical / hydraulic actuator.
• an inlet 5 is provided, coming from the high-pressure collection chamber, which opens into the bore 3 in the housing 2 of the injector 1 in the region of a constriction point on the control part 4.
• a valve chamber 8 is provided in the housing 2 of the injector 1 below the mouth of the inlet 5 from the high-pressure collector chamber.
• the valve chamber 8 is designed with a valve chamber diameter 9.
• a head area 6 of the control part 4 is formed with a diameter.
• control edges 36 and 37 on the control part are formed at the upper end of the head region 6 and at its lower end (cf. illustration according to FIG. 2).
• the seat diameters and the guide diameters are all made in the same diameter 7.
• a nozzle inlet opening 10 branches off from the approximately diamond-shaped configured in the housing 2, to which is connected a nozzle inlet 11 which extends through the injector housing 2 and which opens into a nozzle chamber 12.
• the nozzle inlet 12 is provided in the front area of an injection nozzle system and, with its nozzle tip 33, opens into the combustion chamber of a direct-injection internal combustion engine.
• the first slide element 13 is surrounded by a leakage oil ring space 14 which extends around it in an annular manner and is formed in the housing 2 of the injector 1.
• a leak oil hole branches off from the leak oil ring space 14 and opens into a leak oil line 16 on the outflow side. Excess fuel that flows out of the high pressure during the nozzle discharge can be returned to the fuel tank of the motor vehicle via the leak oil line 16.
• a first branch from the nozzle inlet 11 also opens into the leak oil ring chamber 14, via which the injection nozzle system consisting of the nozzle inlet 11, the nozzle chamber 12 and the injector 34 can be relieved of pressure after an injection phase 41 or 42 (cf. FIG. 3).
• the first slide element 13 is followed by a constriction, seen in the axial direction of the control part 4, to which a second slide element 21 is connected in the end region of the control part 4.
• This second slide element 21 is also designed with the diameter 7 of the control part 4, with which it is guided in the bore 3 of the housing 2 of the injector 1.
• the second slide element 21 is also enclosed on the housing side by an annular space 22 assigned to it, which is also connected via an opening to the nozzle feed line 11 in the housing 2.
• a sealing spring 25 is arranged below an end face 26 of the second slide element 21.
• the sealing spring 25, designed as a compression spring, is received in a cavity 27 in the housing 2.
• a cavity is formed separately therefrom, in which a spring element 31 is accommodated.
• the spring element 31 received in this cavity acts on an end face 30 of a nozzle needle 29 and presses the nozzle needle 29 into its nozzle seat 34.
• a pressure stage 35 is formed on the nozzle needle 29 in the area which is surrounded by the nozzle chamber 12.
• the nozzle tip moves 33 back from their seat 34, so that the injection of an injection quantity of fuel under high pressure can take place either during a pre-injection phase, during the main injection phase or during a post-injection phase into the combustion chamber of a direct-injection combustion engine.
• the cavity in which the spring element 31, which acts on the nozzle needle 29, is received, is connected via an outlet line 32 to the already mentioned leak oil line 16, which already has a branch 15 for the discharge of the leak oil from the annular spaces provided in the injector 2 14 or 22 provides.
• the overlap of the stroke paths 20 and 24 on the two leakage oil slide elements 13 and 21 provided on the downstream side corresponds to the stroke of the control edges formed on the head region 6 of the control part 4.
• the head region 6 of the control part 4 contains at its upper or lower outlet on the guide diameter 7, in which the guide or seat diameter of the control part 4 is made, two control edges 36 or 37.
• the degree of coverage of the upper control edge 36 or the lower control edge 37 corresponds to that at the Leakage oil slides 13 and 21 adjustable stroke paths 20.
• the valve chamber 8 can be designed as a throttle gap 38, provided that the inside diameter of the valve chamber 38 and the outside diameter of the head region 6 are matched to one another accordingly.
• the outlet of the gap-shaped valve chamber 8 or 38 forms the first leakage oil slide 13, which is designed to move up and down in diameter 7 in the bore 3 of the housing 2 of the injector 1.
• 3 shows the temporal courses of the control part stroke or the injection phases, each plotted over the time axis.
• the stroke of the control part 4 is plotted in the vertical direction over the time axis.
• the control part is moved with its head region 4 to the stop of the housing 2, on which the lower control edge 37 of the. Head area.
• the control part 4 is acted upon by an actuator that realizes at least two control states, such as an electromagnet or a piezo actuator.
• the head region 6 In order to carry out the pilot injection, the head region 6 must therefore carry out its longest travel range until the control edge 37 bears against the corresponding control edge of the housing 2 and switches through the valve chamber 8, 38.
• control part 4 is held approximately centrally in its position with respect to the valve space 8, 38 formed in the housing 2 of the injector 1.
• This state corresponds to the second plateau, which is the first plateau located at a higher level according to the curve in the upper diagram of the two diagrams according to FIG. 3.
• the pre-injection and main injection phases 41 and 42 that are established are shown in the lower diagram.
• the pre-injection phase 41 can assume two courses, as shown in the lower diagram in FIG. 3.
• the first course with a significantly lower injection quantity is shown in solid lines, while alternatively a dashed curve curve shows a pre-injection phase 41, which lasts longer on the one hand and during which a higher injection volume can be injected on the other hand.
• the pre-injection phase 41 is followed by an injection pause, in which the injection nozzle system 11, 12, 34 is relieved of pressure before during the Main injection phase, an essentially triangular injection profile can be implemented in the injection nozzle.
• the mode of operation of the multi-stage switching injector proposed according to the invention is as follows:
• the control part 4 which is displaceably mounted in its housing 2 in FIG. 1, is assigned a piezo-actuator, an electromagnet or a similar externally actuable switching element with which the control part 4 can be moved up and down in its bore 3 in the housing 2 of the injector 1.
• the control part 4 is moved vertically downward by the valve actuation unit, so that the control edge 37 formed on the underside of the head region 6 sits on its seat in the housing 2 and the gap-shaped valve chamber 8, 38 briefly with the inlet 5 from High pressure collection room.
• a fuel quantity corresponding to the pre-injection quantity can enter the nozzle inlet 11 via the mouth 10 and reach the nozzle chamber 12.
• the transverse bores 15 and the further transverse bore located underneath are closed by the leakage oil slides 13 and 21 formed in the outflow region of the control part 4, so that the nozzle inlet is sealed on the leakage oil side during the pre-injection phase.
• This ensures that the metered pre-injection quantity of fuel is present in the nozzle chamber 12 for performing the injection.
• the nozzle needle 29 moves up against the spring force effect of the spring element 31, since the high pressure is present at the pressure stage 35 of the nozzle needle 29.
• the injector tip 33 is retracted from its seat 34 on the combustion chamber of a direct injection spreading machine so that fuel can be injected into the combustion chamber of a direct injection spray machine.
• the control part 4 is moved upwards in the vertical direction, as a result of which the concealed head region 6 is positioned in a central position within the valve chamber 8, 38.
• the annular spaces 14 and 22 in the housing 2, which are provided on the leakage oil side are closed by the two leakage oil slides 13 and 21 provided on the outflow side.
• the area acting as the throttle gap is imid Valve space 8, 38 via the inlet 5 from the high-pressure collecting space from high pressure in the injection nozzle system 11, 12, 34.
• the pressure relief after the main injection phase 42 takes place as indicated in the illustration according to FIG. 1, by moving the thickened head region 6 to its upper stop in the housing 2, by opening the leak oil ring space 14 by opening the control edges 17 and 18 on the first leak oil slide element.
• the injection nozzle system 11, 12, 34 is relieved of pressure on the leakage oil side by opening the control edges 24 and 23 on the annular space 22, so that the high pressure can be reduced in the leakage oil line 16 provided on the housing.
• control part 4 Due to the design of the control part 4 according to the invention and the design of the valve chamber 8 as a throttle-shaped gap with a corresponding adjustment of the diameter 9 or outer diameter of the head region 6, 2/3 directional control valves can be formed on the control part 4.
• the design of the control part with essentially the same diameter in guide areas and in seating areas (diameter 7) allows the force-balanced design of the control part 4 that can be moved in the bore 3 of the injector housing 2.
• the pre-injection stroke and the main injection center position of the head area 6 in the throttle-gap-shaped valve chamber 8, 38 can be realized, so that the injection quantity to be injected during the pre-injection phase can be metered by appropriately fast or slow activation of the lower control edge 37 of the head area 6 is.
• the diameter ratio of the thickened head region 6 on the control part 4 in relation to the inside diameter of the throttle-gap-shaped valve chamber 8, 38 the mean flow into the injection nozzle system 11, 12, 34 from the inlet 5 of the high-pressure collection chamber can be designed accordingly.

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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 (3)

Publications (1)

Family

ID=7647145

Family Applications (1)

Country Status (6)

Families Citing this family (9)

Family Cites Families (11)

• 2000
  • 2000-06-29 DE DE10031574A patent/DE10031574B4/de not_active Expired - Fee Related
• 2001
  • 2001-06-07 KR KR1020027002412A patent/KR20020027576A/ko not_active Application Discontinuation
  • 2001-06-07 US US10/069,729 patent/US6932281B2/en not_active Expired - Fee Related
  • 2001-06-07 JP JP2002506363A patent/JP2004502076A/ja active Pending
  • 2001-06-07 EP EP01949245A patent/EP1299639A1/de not_active Withdrawn
  • 2001-06-07 WO PCT/DE2001/002143 patent/WO2002001067A1/de not_active Application Discontinuation

Non-Patent Citations (1)

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