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
  • 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
  • F02M45/08—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
  • 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
  • F02M45/08—Injectors peculiar thereto
  • F02M45/083—Having two or more closing springs acting on injection-valve
• • 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
  • F02M45/08—Injectors peculiar thereto
  • F02M45/086—Having more than one injection-valve controlling discharge orifices
• • 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
  • F02M47/06—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
  • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
  • F02M2200/46—Valves, e.g. injectors, with concentric valve bodies
• • 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
  • F02M63/0026—Valves characterised by the valve actuating means electrical, e.g. using solenoid using piezoelectric or magnetostrictive actuators

Definitions

• the present invention relates to an injection nozzle for internal combustion engines with the features of the preamble of claim 1.
• Such an injection nozzle is known for example from DE 100 58 153 AI and has a nozzle body on which at least one first spray hole and at least one second spray hole are formed.
• a first nozzle guide designed as a hollow needle, is guided in a first needle guide of the nozzle body and can be used to control the injection of fuel through the at least one first spray hole.
• a second nozzle needle is arranged coaxially in the first nozzle needle, with which the injection of fuel through the at least one second spray hole can be controlled.
• the second nozzle needle is drive-connected to a drive piston which, in a control chamber, has a control surface which is effective when pressure is applied in the closing direction.
• the injection nozzle according to the invention with the features of the independent claim has the advantage over the fact that there is no need to control a separate control chamber with regard to the pressure therein in order to actuate the second nozzle needle.
• the invention is based on the general idea to provide a mechanical driver for actuating the second nozzle needle, which the
• Stroke movement of the first nozzle needle couples with a stroke movement of the second nozzle needle from a predetermined forward stroke of the first nozzle needle.
• the opening of the second nozzle needle is thus controlled as a function of the opening stroke of the first nozzle needle.
• the second nozzle needle can be designed in such a way that it has no pressure stage.
• the cross-sectional area in the sealing seat of the second nozzle needle corresponds to the cross-sectional area of a second needle guide provided for the second nozzle needle.
• the result of this design is that the pressure forces acting on the second nozzle needle in the opening direction do not change when the first nozzle needle is opened.
• This design supports a simplified structure for the injection nozzle.
• the end of the second nozzle needle remote from the spray holes can be arranged in a first leakage space, the second nozzle needle then being biased in the closing direction by a second spring.
• the leakage space is usually relatively depressurized, so that essentially only the second spring acts on the second nozzle needle in the closing direction.
• the second nozzle needle can thus be closed or opened with comparatively small forces.
• driver contours formed on the nozzle needles which generate the desired mechanical positive coupling between the nozzle needles when the advance stroke is reached, can be arranged such that they interact with one another in the first leakage space. Accordingly, there is a relatively low ambient pressure in the vicinity of the driver contours, which supports the proper function of the driver contours.
• Fig. 1 to 3 greatly simplified longitudinal sections through injection nozzles at different
• Injection nozzle 1 on a nozzle body 2 is equipped with at least one first spray hole 3 and with at least one second spray hole 4, which usually open into a combustion chamber or premixing chamber 5 of an internal combustion engine (not shown) several first spray holes 3 and / or several second spray holes 4 are provided.
• the nozzle body 2 contains a first needle guide 6 in which a first nozzle needle 7 is adjustably mounted in a stroke-movable manner.
• the first nozzle needle 7 is designed as a hollow needle and contains a second needle guide 8, in which a second nozzle needle 9 is mounted such that it can be moved in a stroke-movable manner.
• the second nozzle needle 9 is arranged coaxially with the first nozzle needle 7.
• An annular first sealing seat 12 which is arranged upstream of the first spray hole 3, is formed between a first needle tip 10 facing the spray holes 3, 4 and a nozzle tip 11 containing the injection holes 3, 4.
• the cross-sectional area 13 in the first sealing seat 12 is smaller than the cross-sectional area 14 of the first needle guide 6, as a result of which the first nozzle needle 7 has a pressure stage.
• the respective cross sections 13, 14 are symbolized by arrows.
• the first nozzle needle 7 is at least a first one Spray hole 3 controllable, while with the second nozzle needle 9 the at least one second spray hole 4 is controllable.
• a first driver contour 19 is now formed on the first nozzle needle 7, which is designed here in the form of a ring step.
• a second driver contour 20 is formed on the second nozzle needle 9 corresponding to the first driver contour 19.
• the second driver contour 20 can also be formed by an appropriately designed ring step.
• at least two radially projecting webs 21 are provided to form the second driver contour 20, which webs have a transverse bore 22 at an end 23 of the second nozzle needle 9 remote from the second needle tip 15.
• other constructions can also be suitable for the configuration of the driver contours 19, 20.
• both nozzle needles 7, 9 are closed.
• the driver contours 19, 20 are arranged such that a distance 24 between the two drivers 19, 20 is formed in the stroke direction in the closed position of both nozzle needles 7, 9. This distance 24 is also referred to below as the preliminary stroke 24.
• the nozzle body 2 also contains a supply line 25 which serves to supply the spray holes 3, 4 with a fuel under high pressure.
• the feed line 25 usually comes from a high-pressure collection space, not shown here, which is fed with a corresponding high-pressure pump, the so-called “common rail principle”.
• the feed line 25 leads in the nozzle body 2 to a nozzle space 26, from which the spray nozzles 3, 4 be fed with fuel via an annular space 27.
• a translator piston 28 is also mounted in a stroke-adjustable manner in the nozzle body 2.
• This booster piston 28 usually forms part of the first nozzle needle 7, or the booster piston 28 is at least coupled to the first nozzle needle 7 for transmitting tensile and compressive forces in the stroke direction.
• the booster piston 28 has a first surface 29 which is arranged in a compensator chamber 30 and is exposed to the pressure prevailing there.
• the compensator chamber 30 communicates with the supply line 25 via a bore 31, so that the high fuel pressure usually prevails in the compensator chamber 30.
• a first spring 32 which is supported on the one hand on the nozzle body 2 and on the other hand on the booster piston 28, the first spring 32 prestressing the booster piston 28 and thus the first nozzle needle 7 in its closing direction. Since the first surface 29 faces away from the first needle tip 10, the first surface 29 acts in the closing direction of the first nozzle needle 7 when pressure is applied.
• the second control chamber 36 is connected to the supply line 25 via an infeed channel 39, an infeed valve 40 being arranged in the infeed channel 39.
• This feed valve 40 can, for example, as
• the booster piston 28 forms, together with the first nozzle needle 7, a jointly stroke-adjustable unit.
• the first driver contour 19 is the first Nozzle needle 7 formed on the translator piston 28.
• the end 23 of the second nozzle needle 9 remote from the second needle tip 15 is preferably arranged in a first leakage space 45.
• the first leakage space 45 is connected via a leakage line 46 to a relatively unpressurized reservoir.
• a second leakage space 47 is arranged in the stroke direction between the nozzle space 26 and the first control space 34 and communicates with the first leakage space 45 via at least one bore 48. In this second leakage space 47 can leakages between the
• the injection nozzle 1 corresponding to the embodiment according to FIG. 1 works as follows:
• Opening stroke through which takes the first nozzle needle 7 and / or wherein the first nozzle needle 7 is driven by its pressure stage in the opening direction and follows the booster piston 28.
• the force balance prevailing on the unit consisting of first nozzle needle 7 and booster piston 28 leads to a resultant force which is effective in the opening direction.
• the first nozzle needle 7 performs an opening movement in which the first needle tip 10 lifts off the first sealing seat 12, so that the at least one first spray hole 3 with the
• Nozzle chamber 26 is connected and can inject fuel into combustion chamber 5 or premix chamber 5.
• the second nozzle needle 9 remains in its closed position. However, as soon as the opening movement of the first nozzle needle 7 reaches the preliminary stroke 24, the driver contours 19, 20 come into contact or engage.
• the forces to be applied by the first nozzle needle 7 for driving the second nozzle needle 9 are comparatively low, since essentially only the closing force of the second spring 50 has to be overcome.
• the actuator is actuated to retract the actuator piston 38.
• the pressure in the control spaces 34 and 36 drops at least to the pressure in the supply line 25.
• the pressure can also drop lower since the feed valve 40 also generates a pressure drop.
• the first nozzle needle 7 is driven again in the closing direction.
• the second nozzle needle 9 is depressurized at the second needle tip 15, so that the closing force of the second spring 50 closes the second nozzle needle 9 at the latest.
• the stroke of the first nozzle needle 7 can thus be set via the adjustable stroke of the actuator piston 38.
• the second nozzle needle 9 can also be controlled to open via the opening stroke of the first nozzle needle 7.
• the actuation of the two nozzle needles 7, 9 can thus be realized with only a single actuator, as a result of which the injection nozzle 1 according to the invention can be produced particularly inexpensively.
• FIG. 2 shown in a second exemplary embodiment of the inventive injector 1.
• Fig. 2 shown in a second exemplary embodiment of the inventive injector 1.
• the first nozzle needle 7 is also driven in this embodiment by a booster piston 51, which can form part of the first nozzle needle 7 or at least forms a jointly adjustable unit with the latter.
• the booster piston 51 has a first surface 52, which is arranged in a first booster chamber 53 and can be acted upon by a pressure therein.
• the first surface 52 faces away from the first needle tip 10, so that it is at
• the booster piston 51 is biased with a first spring 54 in the opening direction of the first nozzle needle 7.
• the first spring 54 is supported on the outside
• Translator piston 51 arranged second leakage space 55 e at the end of the nozzle body 2 and at the other end at a step 56 on the translator piston 51.
• the second leakage space 55 communicates with the inner first leakage space 45 via at least one bore 57.
• the first booster chamber 53 communicates via a booster channel 58 with a second booster room 59.
• a return stroke surface 60 of a control piston 61 is arranged and can be pressurized.
• the return stroke surface 60 faces away from the spray holes 3, 4.
• the control piston 61 also has a pre-stroke surface 62 which faces the spray holes 3, 4, is arranged in a control chamber 63 and can be acted upon by pressure.
• the control room 63 communicates with the supply line via a bore 64 25. The selected arrangement separates the control piston 61 from the second transmission chamber 59 from the control chamber 63.
• a throttle path 66 is formed radially between the control piston 61 and a control piston guide 65, via which the second transmission chamber 59 with the control chamber 63 (throttled) communicates.
• the throttle path 66 enables a pressure equalization between the control chamber 63 and the second translation chamber 59 in static conditions or in the case of relatively slow movements, so that the same pressure prevails in the second translation room 59 and consequently also in the first translation room 53 as in the control room 63, that is to say, as well Supply line 25.
• the transmission chamber 59 does not take place quickly enough via the throttle path 66, so that the control piston 61 in the second transmission chamber 59 can generate overpressures and depressions relative to the control chamber 63.
• the injector 1 according to the invention corresponds to the embodiment according to F g. 2 works as follows:
• both nozzle needles 7, 9 are closed.
• both nozzle needles 7, 9 are closed.
• the translator chamber 59 and the control chamber 63 have the same pressure as in the supply line 25. In this state, a resulting force acting in the closing direction is established on the first nozzle needle 7.
• the second nozzle needle 9 is in the area of its second
• Needle tip 15 is relatively depressurized, so that the restoring force of the second spring 50 can be dimensioned to be relatively small in order to close the second nozzle needle 9.
• the volume of the second translation chamber 59 increases, as a result of which the pressure drops there.
• This pressure drop propagates to the first translation chamber 53, as a result of which the force balance on the first nozzle needle 7 changes.
• the first nozzle needle 7 lifts off the first sealing seat 12, so that the at least one first spray hole 3 communicates with the nozzle chamber 26 and, accordingly, fuel the combustion chamber / premixing chamber 5 emdusen can.
• the stroke movement 67 of the control piston 61 is dimensioned such that the opening movement of the first nozzle needle 7 does not exceed the preliminary stroke 24.
• the actuator is controlled in such a way that the control piston 61 executes a further stroke movement.
• the first nozzle needle 7 continues to lift off the first sealing seat 12 so that its opening movement exceeds the predetermined preliminary stroke 24.
• the driver contours 19, 20 come into engagement with one another, so that the first nozzle needle 7 takes the second nozzle needle 9 with it as it continues to move. The movement of the second nozzle needle 9 lifts it from the second sealing seat
• the actuator is actuated so that the control piston 61 moves back and the volume of the second translator space 59 is reduced again. Consequently, the pressure there rises again approximately to the pressure prevailing in the supply line 25.
• the force balance on the second nozzle needle 7 is thereby changed again, so that a closing force results which closes the first nozzle needle 7.
• the force balance on the second nozzle needle 9 also changes such that the closing force of the second spring 50 predominates and the second nozzle needle 9 also closes.
• the two nozzle needles 7, 9 can be controlled with only a single actuator.
• FIG. 3 shows a third exemplary embodiment of the injection nozzle 1 according to the invention. Because of the matches with the first two
• a translator piston 68 is also provided in this embodiment for driving the first nozzle needle 7, which piston forms a unit that is stroke-adjustable together with the first nozzle needle 7.
• Booster piston 68 has a first surface 69, which m is arranged in a control room 70 and can be exposed to pressure there.
• the first surface 69 faces away from the spray holes 3, 4, so that it acts in the closing direction when pressure is applied.
• the booster piston 68 contains one inside
• Piston guide 71 in which a control piston 72 is mounted so as to be adjustable in stroke.
• the control piston 72 is arranged coaxially in the booster piston 68.
• the control piston 72 is coupled to an actuator 74 via a coupling rod 73, such that the actuator 74 can exert at least compressive forces on the control piston 72 via the coupling rod 73.
• the control piston 72 has a control surface 75, which is likewise arranged in the control chamber 70 and can be acted upon by pressure. Furthermore, the control piston 72 is driven by means of a first spring 76 and by means of the second spring 51 m in the direction of a reduction in the volume of the control chamber 70.
• the first spring 76 is supported between the nozzle body 2 and a piston 77, which is connected to the actuator 74. If the pressure-rigid coupling between the actuator 74, the coupling rod 73 and the control piston 72 can also transmit tensile forces, the first spring 76 directly biases the control piston 72 in the direction of a volume reduction in the control chamber 70. However, provided the coupling between the actuator
• the first spring 76 only causes the actuator 74 to reset and thus relieves the pressure on the control piston 72, as a result of which the preload of the second spring 51 can act more strongly in the direction of a volume reduction in the control chamber 70.
• the injection nozzle 1 also has a filling space 78 which here surrounds the coupling rod 73 in an annular manner.
• Filling space 78 communicates with the through a bore 79 Supply line 25.
• a coupling rod guide 80 is provided between the filling chamber 78 and the control chamber 70, which guides the coupling rod 73 axially.
• the control room 70 is fed from the filling room 78. For this purpose, is radial between the coupling rod 73 and the
• Coupling rod guide 80 em throttling path 81 formed, which communicates the control chamber 70 with the filling chamber 78, but throttled.
• a pressure equalization between the filling chamber 78 and the control chamber 70 can be established via the throttle path 81, so that the same pressure prevails in the control chamber 70 as in the supply line 25.
• the pressure between the filling chamber 78 and the control chamber 70 cannot be compensated quickly enough, which can be used to control the nozzle needles 7, 9.
• the second spring 51 is not supported directly on the nozzle body 2 but on the control piston 72. Accordingly, the second spring 51 on the one hand biases the second nozzle needle 9 in its closed position and on the other hand e ne
• the injection nozzle 1 according to the embodiment of FIG. 3 operates as follows:
• the actuator 74 is actuated in such a way that it carries out a lifting movement in accordance with the arrow 67.
• the stroke of the actuator 74 is transmitted to a stroke of the control piston 72 via the coupling rod 73.
• the stroke of the control piston 72 causes a displacement of the control surface 75, as a result of which the volume of the control chamber 70 increases. Since this volume change takes place very quickly, fuel cannot flow through the throttle path 81 quickly enough, so that an underpressure arises in the control chamber 70.
• the pressure drop in the control chamber 70 results in a change in the force balance on the first nozzle needle 7, such that the forces of the pressure stage of the first nozzle needle 7 which are effective in the opening direction now predominate.
• a resulting force acting in the opening direction is thus set on the first nozzle needle 7, so that the first nozzle needle 7 lifts off the first sealing seat 12.
• the at least one first injection hole 3 communicates with the nozzle space 26 and can emit fuel into the space 5.
• the actuation of the actuator 74 or the activation of the Control piston 72 so that the opening stroke of the first nozzle needle 7 is smaller than the predetermined preliminary stroke 24.
• the actuator 74 is actuated to a further stroke position, so that the control piston 72 coupled therewith also carries out a further stroke movement.
• the first nozzle needle 7 lifts even further from the first sealing seat and exceeds the predetermined preliminary stroke 24.
• the desired interaction of the two driver contours 19, 20 occurs, so that the opening stroke movement of the second nozzle needle 7 that goes beyond the preliminary stroke 24 takes along the first nozzle needle 9.
• the second nozzle needle 9 lifts off from the second sealing seat 16, so that as a result, the at least one second spray hole 4 likewise communicates with the nozzle chamber 26 and fuel can be emitted into the chamber 5.
• the actuator 74 is actuated to reset the control piston 72, which can be supported by the first spring 76.
• the second spring 51 also supports the restoring movement of the control piston 72.
• the second spring 51 simultaneously drives the second nozzle needle 9 in its closed position.
• only the first nozzle needle 7 or first the first nozzle needle 7 and then the second nozzle needle 9 can be actuated to open with only a single actuator 74.

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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 (1)

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Family Applications (1)

Country Status (6)

Families Citing this family (7)

Family Cites Families (13)

• 2003
  • 2003-06-10 DE DE10326044A patent/DE10326044A1/de not_active Withdrawn
• 2004
  • 2004-05-13 WO PCT/EP2004/050785 patent/WO2004109091A1/de not_active Application Discontinuation
  • 2004-05-13 JP JP2006516109A patent/JP2006527332A/ja active Pending
  • 2004-05-13 US US10/538,031 patent/US20060186226A1/en not_active Abandoned
  • 2004-05-13 KR KR1020057023581A patent/KR20060021351A/ko not_active Application Discontinuation
  • 2004-05-13 EP EP04732617A patent/EP1636482A1/de not_active Withdrawn

Non-Patent Citations (1)

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