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
  • F02M57/00—Fuel-injectors combined or associated with other devices
  • F02M57/02—Injectors structurally combined with fuel-injection pumps
  • F02M57/022—Injectors structurally combined with fuel-injection pumps characterised by the pump drive
  • F02M57/023—Injectors structurally combined with fuel-injection pumps characterised by the pump drive mechanical
• • 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
  • F02M55/04—Means for damping vibrations or pressure fluctuations in injection pump inlets or outlets
• • 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
  • F02M59/20—Varying fuel delivery in quantity or timing
  • F02M59/36—Varying fuel delivery in quantity or timing by variably-timed valves controlling fuel passages to pumping elements or overflow passages
  • F02M59/366—Valves being actuated electrically
• • 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
  • F02M59/44—Details, components parts, or accessories not provided for in, or of interest apart from, the apparatus of groups F02M59/02 - F02M59/42; Pumps having transducers, e.g. to measure displacement of pump rack or piston
  • F02M59/46—Valves
  • F02M59/466—Electrically operated valves, e.g. using electromagnetic or piezoelectric operating means
  • F02M59/468—Electrically operated valves, e.g. using electromagnetic or piezoelectric operating means using piezoelectric operating means

Definitions

• the present invention relates to a pump-valve-nozzle unit (PVD) in a stretched arrangement with hydraulic-mechanical transmission.
• PVD pump-valve-nozzle unit
• DE 39 10 793 A1 relates to a fuel injection device for diesel internal combustion engines with at least one pump piston. This is sealingly guided in a sleeve and, together with the pump body, forms a delivery chamber which is connected to a suction chamber by a control element during the downward movement of the pump piston, the delivery chamber being in flow communication with an injection valve via an injection line.
• the invention has for its object to keep the harmful space of the fuel injector as small as possible in order to be able to achieve high injection pressures. This is achieved in that there is a permanently open flow connection between the delivery chamber and the injection valve.
• DE 198 09 627 A1 relates to a fuel injection device for internal combustion engines.
• This includes a high-pressure fuel pump which is connected on the suction side to a low-pressure fuel supply system and on the high pressure side to a fuel injection valve which projects into the combustion chamber in the internal combustion engine.
• the high-pressure delivery in a high-pressure channel provided between the high-pressure fuel pump and the fuel injection valve can be controlled by means of an electrical control valve, which has an electrically actuatable, displaceable valve member with a valve sealing surface. With the valve sealing surface, it interacts with a stationary valve seat to form a sealing cross section.
• the control valve member and / or a sleeve guiding it are made of ceramic.
• the L-shaped arrangement from the valve to the injection nozzle can lead to pressure pulsations in the system.
• No. 4,782,807 shows a cam-operated pump-nozzle fuel injection device, in which a pump piston can be moved into a pump chamber, from which a bore branches off.
• the bore branching off from the pump work space opens at a constriction point of a valve element which can be moved by an actuator.
• Another bore branches off below the valve element, via which fuel flows to the nozzle part of the pump-nozzle fuel injection device according to US Pat. No. 4,782,807.
• the pump unit consisting of pump piston and pump working space, that this valve member, which can be actuated by the actuator, and the nozzle body according to this solution, are hydraulically connected one behind the other in relation to the fuel flow.
• an essentially vertical arrangement of a pump part, a valve part adjoining this and a nozzle part of an injection arrangement adjoining the valve part can be ensured.
• a largely flow-free pressure build-up can be achieved.
• the components PVD are hydraulically seen, all in a row.
• the straight arrangement of the PVD units allows one Flange on the side of a hydraulic-mechanical translator. Due to the essentially vertical arrangement of the pump part, valve part and nozzle part, an aspect ratio between the pump chamber and the control valve chamber and the control valve chamber to the nozzle chamber of 1: 5 can be optimally realized between these parts.
• the valve chamber can be designed in an optimal manner with regard to the aspect ratios of the line systems.
• the mechanical stroke paths required to actuate the control valve can be easily adjusted.
• the actuating unit contains a mechanical transmission in the form of a lever which can be pivoted about an axis of rotation, the hydraulic Translation volume can be kept small, which can be operated with very low pressures (only 6 bar).
• the vertical arrangement of the PVE units of an injector proposed according to the invention is accompanied by the advantage that, instead of the three to four high-pressure bore intersections in the injector body previously required, only two high-pressure bore intersections in the injector body are now necessary.
• the high-pressure bore intersections In order to ensure a pressure threshold strength of up to approx. 2000 bar of an injector body for high-pressure diesel injection systems, the high-pressure bore intersections must be minimized, since these impair the mechanical strength of the injector body.
• the high-pressure bore intersections define the limit of the mechanical stress on an injector body, which limits the pressure level that can be achieved in the high-pressure collecting space (common rail).
• FIG. 1 shows the Y or L-shaped arrangements of the components which have arisen in previous solutions on PVD systems.
• FIG. 2 schematically shows the arrangement of the components of a pump-valve-nozzle system of an injector proposed according to the invention.
• the essential components of the fuel injection device 1 are arranged in the vertical direction. With regard to the fluid direction of the fuel coming from the pump part P under high fuel, the components P, V and D are hydraulically arranged one behind the other. With this configuration, on the one hand, construction space is saved, which is only very scarce available on the cylinder head of an internal combustion engine, and the supply line connecting the individual parts P, V and D of the fuel injection device can be designed in the optimum length. This is an optimal behavior with regard to the build-up of pressure fluctuations of the fuel under high pressure in the Supply lines can be achieved if the length ratio of the supply lines 5 or 8, ie 1 : 1 2 is in the range between 1: 4 and 1: 6. The length ratio of the two inlet bores 5 and 8 (cf.
• FIG. 3 is preferably 1: 5.
• This selected length ratio of the inlet and connection lines between the components of the pump-valve-nozzle system of a fuel injection device 1 a largely vibration-free pressure build-up in the fuel injection device 1 can be achieved.
• Vibration-free pressure build-up within a pump-valve-nozzle system offers the possibility, in further development of the injection systems, to achieve a boat pre-injection, which is very difficult to achieve in the injection system which is subject to considerable pressure pulsations, the precision of the pre-injection or Boat quantities left something to be desired
• FIG. 3 shows the optimal spacing relationships of the pump part, valve part and nozzle part of a fuel injection device with regard to the pressure oscillation structure.
• the pump part P consisting of the pump piston 3, which dips into the pump chamber 4, is connected to the valve chamber 6.1 via the inlet bore 5.
• the length of the inlet bore 5 connecting the pump chamber 4 to the valve chamber 6.1 is denoted by l 1 .
• the inlet bore 8 extends from the valve chamber 6.1 through the injector body to the nozzle chamber, denoted by reference numeral 12.
• the length of the axial extension of the inlet bore 8 between the valve chamber 6.1 and the nozzle chamber 12 of the injector body is denoted by l 2 .
• the ratio of the lengths l 1 , l 2 of the inlet bore 5 to the inlet bore 8 is advantageously in the range between 1: 4 and 1: 6, the length ratio l is preferably 1 : l 2 , 1: 5. With these length ratios of the inlet bores 5 and 8 in the interior of the injector body of the fuel injection device 1, the structure of Avoid pressure pulsations in the high pressure fuel fluid effectively.
• FIG. 4 shows an embodiment variant of the PVD unit proposed according to the invention with hydraulic, mechanical translators flanged to the side in the area of the valve part V.
• the injector 1 contains in its upper region a pump part P. This receives a pump piston 3 provided coaxially to the line of symmetry of the injector body 1 in a bore 2, which is acted upon by a cover together with a compression spring enclosed by the cover.
• the pump piston 3 plunges into a pump chamber 4 and in this way pressurizes an existing fuel supply there.
• a bore 5 extends from the pump chamber 4 into a valve chamber 6.1 of a control valve 6, which is received in a valve part V of the injector of the fuel injection device 1.
• the length of the inlet bore 5 between the pump chamber 4 and the valve chamber 6.1 is denoted by I 1 .
• the control part 6 closes the connection between the inlet bores 5 and 8 with the seat surface 6.5.
• a push rod 6.4 is also formed on the control part 6, the rounded head of which protrudes laterally from the injector body 1. In the position of the control part 6 shown in FIG.
• an inlet bore 8 extends, which runs essentially parallel to the axis of symmetry of the valve body 1, to the nozzle chamber 12.
• the nozzle chamber 12 is penetrated by a nozzle needle 11, the nozzle seat 13 of which is formed at the tip of the injector body 1 and one Nozzle opening 14, which projects into the combustion chamber of an internal combustion engine, either closes or releases it.
• a pressure piece 10 is reproduced, which can be acted upon by a plate with a compression spring 9, which is completely enclosed by the injector body housing.
• the nozzle part D of the fuel injection device is located at a distance l 2 from the valve part of the pump-valve-nozzle unit of the fuel injection device 1.
• the ratio of the lengths l 1 of the inlet bore 5 to the length of the inlet bore 8 between the valve chamber 6.1 of the valve part V and the Nozzle space 12 of the nozzle part D is advantageously essentially 1: 5 in accordance with the explanations given above.
• the nozzle part D is connected to the injector body 1 by means of a screw connection 15.
• the centering of the nozzle part D to ensure the alignment of the inlet bore 8 in the nozzle chamber 12 is made possible by the centering pin 16 or 17, which are provided between the components to be assembled with one another.
• a translator flange 7 is arranged on the side surface of the injector, in which a translator lever 18 which can be pivoted about an axis is received.
• the translator lever 18 is acted upon on the one hand by a return spring 19 and, on the other hand, is connected with its lower end to the rounded end of the push rod 6.4 of the control part 6.
• the rotatably mounted translator lever 18 is moved about its pivot point via the secondary piston 20 provided in the flange 7, 27.
• the secondary piston 20 is connected via a gap-shaped connection through the booster flange 27 to a leak oil reservoir 22 which can be acted upon by a primary piston 23 and which results in actuation of the secondary piston 20.
• a contact plate 24 is provided above the primary piston 23, which in turn can be actuated via a piezo actuator 25.
• the piezo actuator 25 is screwed to the translator flange 27 on an actuator screw connection 26.
• the hydraulic translation volume can be kept low, which means that the refill via the leakage oil pressure with small pressures , for example 6 bar can be driven.
• the mechanical wear that occurs between components 20, 18 and 6.4 of the valve actuation can be very easily compensated for via the leakage gap between primary piston 23 and secondary piston 20 by means of a trailing volume.
• the injector body of the fuel injection device according to FIG. 4 has a pressure threshold strength of pressures of up to at least 2000 bar and advantageously avoids a further high-pressure sealing surface by integrating the compression spring 9 acting on the nozzle needle 11. Sealing surfaces represent potential weak points at the pressures of 2000 bar and more required in injection systems and should therefore be avoided wherever possible.

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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)
• Electromagnetism (AREA)
• Fuel-Injection Apparatus (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=7641758

Family Applications (1)

Country Status (7)

Family Cites Families (13)

• 2000
  • 2000-05-12 DE DE10023236A patent/DE10023236A1/de not_active Withdrawn
• 2001
  • 2001-05-03 BR BR0106421-5A patent/BR0106421A/pt not_active Application Discontinuation
  • 2001-05-03 US US10/030,707 patent/US6659084B2/en not_active Expired - Fee Related
  • 2001-05-03 EP EP01943011A patent/EP1283955B1/de not_active Expired - Lifetime
  • 2001-05-03 CZ CZ20020029A patent/CZ298184B6/cs not_active IP Right Cessation
  • 2001-05-03 WO PCT/DE2001/001682 patent/WO2001086137A1/de active IP Right Grant
  • 2001-05-03 DE DE50101853T patent/DE50101853D1/de not_active Expired - Fee Related
  • 2001-05-03 JP JP2001582710A patent/JP2003532832A/ja active Pending

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