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
  • F02M65/00—Testing fuel-injection apparatus, e.g. testing injection timing ; Cleaning of fuel-injection apparatus
  • F02M65/005—Measuring or detecting injection-valve lift, e.g. to determine injection timing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B3/00—Engines characterised by air compression and subsequent fuel addition
  • F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition

Definitions

• the invention is based on a fuel injection nozzle according to the preamble of claim 1.
• a known injection nozzle of this type EP-Bl 99 991
• the chamber formed in the nozzle holder for receiving the closing spring and the induction coil is provided with an annular shoulder which supports the closing spring with its end facing away from the valve needle and at which the chamber merges into a section with a smaller diameter, which receives the induction coil.
• there is a diameter for the induction coil which is smaller than it should be with regard to the minimum wall thickness of the nozzle holder and which in some cases forces compromises in the design of the induction coil and the evaluation circuit.
• the arrangement according to the invention with the characterizing features of claim 1 has the advantage that the upstream of the support for the closing spring in the nozzle holder is present. whose space can be optimally used to house the induction coil. To a certain extent, the lying support bolt divides the continuous chamber into a spring chamber and a chamber of approximately the same diameter for the induction coil and forms the spring chamber floor with its support surface.
• FIG. 1 An embodiment of the invention is shown in the drawing and explained in more detail in the following description.
• the single figure shows the injection nozzle according to the embodiment, partly in longitudinal section and partly in side view.
• the injection nozzle has a nozzle holder 10 against which an intermediate plate 11 and a nozzle body 12 are clamped by a union nut 13.
• a valve needle 14 is displaceably mounted in the nozzle body 12, on which a closing spring 16 acts via a pressure piece 15 and is accommodated in a chamber 17 of the nozzle holder 10.
• the valve needle 14 cooperates with an inward-facing valve seat in the nozzle body 12 and executes its opening stroke against the direction of flow of the fuel.
• the guide bore of the valve needle 14 is expanded at one point to a pressure chamber, in the area of which the valve needle 14 has a pressure shoulder and via channels in the intermediate disk 11 and the nozzle holder 10, and via a filter 19 with a fuel connection piece 20 of the nozzle senhalters 10 is connected.
• valve Needle 14 attacking fuel pressure pushes the valve needle 14 upward against the force of the closing spring 16 until a shoulder 21 on the valve needle 14 abuts the lower end face of the intermediate plate 11 and limits the further upward stroke of the valve needle 14.
• the closing spring 16 is supported by a spring washer 24 on the flat bottom surface 25 of a recess 26 of a support bolt 27 which is rotatably mounted in a blind bore 28 of the nozzle holder 10.
• the blind bore 28 is sealed to the outside by an O-ring which is embedded in an annular groove of the support bolt 27.
• the chamber 17 of the nozzle holder 10 continues, crossing the blind bore 28, with a slightly reduced diameter up to a housing shoulder 29.
• an induction coil 30 which is part of a needle movement sensor, which is used to detect the start of injection and / or the injection stroke or the injection duration.
• the induction coil 30 has a coil body 31 which is connected to a flange part 32 made of magnetically conductive material and touching the wall of the chamber 17.
• the flange part 32 is provided with a central bore through which an anchor bolt 33, which dips into the coil former 31, is guided with a slight radial play.
• the anchor bolt 33 can be connected to the pressure piece 15 in one piece or via an elongated connecting member 34, so that it moves with the valve needle 14 in both directions.
• a coil core 36 dips into the coil body 31 from above, which is frictionally engaged in a bore 37 of the nozzle holder 10 is seated and its axial position can be adjusted by a screw 38 accessible from the outside.
• the anchor bolt 33 is passed through a central bore 40 in the transverse support bolt 27 and is surrounded there by a helical spring 41 which is supported on the spring washer 24 at the bottom and engages on the flange part 32 at the top.
• the helical spring 41 presses the induction coil 30 against the housing shoulder 29 in a shake-proof manner.
• the induction coil 30 is provided with connection contacts 42, which are located in a lateral recess 43 in the nozzle holder 10.
• a leak oil bore 44 is passed through the coil core 36 and is connected to a leak oil connection bore 46 via a channel 45 in the nozzle holder 10.
• the magnetic field of the induction coil 30 leads over the surrounding area of the nozzle holder 10, the flange part 32, the coil core 36, the armature bolt 33 and the air gap which is formed between the coil core 36 and the armature bolt 33.
• the anchor bolt 33 moves back and forth with the valve needle 14 while constantly changing the air gap to the coil core 36, as a result of which the desired signals of the needle movement are generated.
• the diameter of the induction coil 30 is approximately equal to the outer diameter of the closing spring 16, so that more space is available for the formation and accommodation of the induction coil 30 than in the known designs with a stepped chamber in the nozzle holder 10.

Landscapes

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

Applications Claiming Priority (2)

Publications (1)

Family

ID=6367433

Family Applications (1)

Country Status (4)

Cited By (2)

Families Citing this family (2)

Citations (4)

• 1988
  • 1988-11-18 DE DE19883839036 patent/DE3839036A1/de not_active Withdrawn
• 1989
  • 1989-10-20 WO PCT/EP1989/001252 patent/WO1990005847A1/de not_active Application Discontinuation
  • 1989-10-20 JP JP51115889A patent/JPH04501755A/ja active Pending
  • 1989-10-20 EP EP19890912099 patent/EP0444057A1/de not_active Withdrawn

Patent Citations (4)

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