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
  • 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
• • 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
  • 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
  • F02M47/027—Electrically actuated valves draining the chamber to release the closing pressure

Definitions

• the present invention relates to a
• Fuel injection valves of this type are generally known and are disclosed, for example, in EP-A-0 426 205, EP-A-0 603 616, EP-A-0 824 190, EP-A-1 273 791. They have a pilot valve pin which is controlled by means of an electromagnetic actuator and which, in the closed position, separates an outlet duct of a control chamber provided with a throttle restriction from a low-pressure outlet. When the pilot valve pin is lifted from the pilot valve seat, fuel flows from the outlet duct directly to the low-pressure outlet. An injection process is initiated by opening the pilot valve and the closing movement of the injection valve member is caused to end the injection process by closing the pilot valve.
• a fuel injection valve When opening the pilot valve. of a fuel injection valve according to the invention, fuel flows into a relief chamber, from which it can only continue to flow through a throttle passage to the low-pressure outlet. A minimization of the fuel valve through the low pressure outlet is achieved during the injection process.
• the throttle passage can be formed by a slide fit for the pilot valve pin, but preferably the pilot valve pin is guided in a narrow slide fit and is.
• the relief chamber is connected to the low-pressure outlet via a separately designed throttle passage.
• the pilot valve pin is moved into the relief chamber at high speed until it rests on the pilot valve seat. Since the throttle passage prevents the fuel from being quickly removed from the relief chamber, the movement of the pilot valve pin and the associated displacement of fuel result in a very rapid increase in pressure in the relief chamber and in a discharge chamber adjoining it upstream of the pilot valve seat, which results in a very fast closing movement of the Injector member caused. This can further support this closing movement that the movement of the pilot valve pin is mechanically exploited.
• FIG. 1 shows a longitudinal section of a first embodiment of a fuel injector according to the invention, in which a relief chamber is formed on a retaining nut;
• FIG. 2 likewise shows an enlarged detail of a section of the fuel injector shown in FIG. 1;
• FIG. 3 shows, in the same representation as FIG. 2, a section from a second embodiment of a fuel injector according to the invention with a throttle passage in the pilot valve pin having two throttle constrictions;
• FIG. 4 shows, in the same representation as FIG. 2, a section from a third embodiment of a fuel injector according to the invention, in which the relief chamber is arranged entirely in a drain chamber body on which the pilot valve pin is also mounted;
• FIG. 5 in the same representation as FIG. 2, a section of a fourth embodiment of the fuel injector according to the invention, Similar to that of Figure 3, but with only a single throttle restriction in the throttle passage.
• FIG. 7 a section of a sixth embodiment of the fuel injector according to the invention with a leaf spring valve, similar to that known from EP-A-1 273 791;
• FIG. 8 shows, in the same representation as FIG. 2, a detail from a seventh embodiment of the fuel injection valve according to the invention, in which a control body is mushroom-shaped and is displaceably mounted in the injection valve member;
• Fig. 9 in the same representation as Fig. 2, a section of a. eighth embodiment of the fuel injector according to the invention, in which a transmission pin transmits the movement of the pilot valve pin to a control body.
• FIG. 1 shows in longitudinal section a fuel injection valve 10 according to the invention with an essentially cylindrical valve housing 14, which has a lateral high-pressure inlet 12.
• This has a continuous, stepped bore 17 running in the direction of the longitudinal axis 16, in which an electrical Actuated actuator 18, a control device 20 actuated by the latter and a needle-shaped injection valve member 22 with a closing spring 24 are arranged.
• the injection valve member 22 is held by means of the closing spring 24 on an injection valve seat 26, which is formed on an injection valve seat body 28.
• This is essentially rotationally symmetrical with respect to the longitudinal axis 16, rests on the end face of the valve housing 14 and is held in a sealing manner on the valve housing 14 by means of a union nut 30.
• injection valve nozzles 32 are formed in a known manner, through which fuel is injected under very high pressure into a combustion chamber (not shown) of an internal combustion engine when the injection valve member 22 is directed in the direction by means of the hydraulic control device 20 controlled by the actuator 18 the longitudinal axis 16 is lifted off the injection valve seat 26.
• the injection valve seat 26 delimits a high-pressure space 34, in which the injection valve member 22 is arranged and which on the other hand is delimited by the control device 20 and on the circumferential side by the injection valve seat body 28 and valve housing 14.
• High-pressure chamber 34 is connected to high-pressure inlet 12, through which fuel is fed to high-pressure chamber 34 for injection into the combustion chamber of the internal combustion engine and for controlling injection valve member 22 under very high pressure of up to 1000 bar or even 1800 bar or more.
• the injection valve member 22 delimits a control chamber 36 with its end area facing away from the injection valve seat 26, which on the other hand is bounded by a control body 38 is limited in which an outlet passage 40 equipped with a throttle constriction 40 ′ is formed concentrically to the longitudinal axis 16; see in particular also FIG. 2, which shows a detail of the fuel injector 10 from FIG. 1 with the control device 20 enlarged.
• the control body 38 With its end face 42 facing away from the control chamber 36, the control body 38, with the support of a compression spring 44, which is supported on the one hand on the control body 38 and on the other hand on the injection valve member 22, bears sealingly on an end face 46 'of a mushroom-shaped drain chamber body 46 facing it.
• a relief chamber 48 is formed in the drain chamber body 46 through a longitudinal bore that is coaxial with the longitudinal axis 16 - without throttling constriction - which is aligned with the outlet passage 40 and is directly flow-connected to it.
• the essentially circular cylindrical control body 38 is mounted with radial play of about 0.02 mm to 0.1 mm or 0.2 mm in a control sleeve 50 in the direction of the longitudinal axis 16 and forms as a valve member together with the drain chamber body 46, the end face 46 'acts as a valve seat, an intermediate valve 52.
• the control sleeve 50 at whose end facing the injection valve seat 26, the closing spring 24 is supported, is from the. Force of this closing spring 24 on, drain chamber body 46 held in sealing contact.
• the injection valve member 22 is guided in a close sliding fit with a play of approximately 2 ⁇ m to 10 ⁇ m.
• the mushroom-shaped drain chamber body 46 is sealed against one with its hat part by means of a retaining nut 54 which is threaded into an internal thread on the valve housing 14 Contact shoulder 56 of the valve housing 14 pressed. Furthermore, the retaining nut 54 and the drain chamber body 46 lie against one another in a sealing manner. Distributed in the circumferential direction, at least 2 high-pressure channels 58 are formed in the trunk part of the mushroom-shaped drain chamber body 46, which are in flow connection on the one hand with an annular space 60 delimited by the valve housing 14, the trunk and the head part of the drain chamber body 46 and the control sleeve 50 and which are on the other of the end face 46 'forming the valve seat of the intermediate valve 52.
• the annular space 60 is connected to the high-pressure space 34 and thus to the high-pressure inlet 12 by a longitudinal groove 62 which extends in the axial direction and is formed on the radially outer side of the control sleeve 50.
• the high-pressure channels 58 can, as shown in FIGS. 1 and 2 on the right of the longitudinal axis 16, be produced by oblique bores in the drain space body 46 or, as shown in FIG. 2 on the left of the longitudinal axis 16, by angled bores.
• the orifices of the high-pressure channels 58 on the end face 46 ′ are closed by the control body 38 when the latter lies against the drain chamber body 46.
• a recess 64 can be formed on the drain chamber body 46, which ensures that the contact surface as a relatively narrow, band-shaped area along the outer circumference of the control body 38 and around the mouths of the high pressure channels 58 runs around. Corresponding recesses can of course be formed on the control body 38.
• a pilot valve pin 66 is mounted on the retaining nut 54 concentrically to the longitudinal axis 16 and can be displaced in the direction of the longitudinal axis 16 in a close sliding fit of approximately 2 ⁇ m to 10 ⁇ m. In its closed position shown in FIGS. 1 and 2, the pilot valve pin 66 lies against the drain chamber body 46 and thereby closes the relief chamber 48.
• the drain chamber body 46 forms an annular pilot valve seat 68 which, together with the pilot valve pin 66 as a valve member forms a pilot valve 70.
• the pilot valve seat 68 is designed as a flat seat.
• An annular relief chamber 72 is directly connected to the pilot valve seat 68 on the low pressure side and is formed on the retaining nut 54 serving as the relief chamber body as a recess extending around the pilot valve pin 66.
• This otherwise closed relief chamber 72 is continuously flow-connected via a throttle passage 74 with a low-pressure outlet 76 of the valve housing 14. Fuel flowing out through the low-pressure outlet 76 is fed back to a fuel storage container in a known manner.
• throttle passage 74 can be designed as an oblique bore in the pilot valve pin 66 or, as indicated by dashed lines, on the holding nut 54.
• the diameter of the throttle point 74 'of the otherwise having a larger diameter • throttle passage 74th is, for example, about ten times smaller than the diameter of the pilot valve pin 66 and about five times smaller than the inside diameter of the drainage space 48. However, these ratios can be different. From Another advantage is that the pilot valve pin 66, when it is lifted from the pilot valve seat 68, very quickly releases a substantially larger flow cross-section than is defined by the throttle point 74 '.
• the pilot valve pin 66 is held in contact with the pilot valve seat 68 by means of the actuator 18.
• an actuator shaft 78 rests with its spherically shaped end on the front side of the pilot valve pin 66 facing away from the pilot valve seat 68.
• the actuator 18 is preferably a piezoelectric or magnetostrictive actuator. Such actuators 18 allow only a relatively small stroke of the actuator shaft 78 and thus of the pilot valve pin 66, for example 0.03 mm. However, they have the advantage that they move the pilot valve pin 66 with great speed and great force.
• the actuator 18 is arranged in an actuator housing 80 which projects into the valve housing 14 and is fastened to the latter by means of a fastening screw 82.
• the game between the control body 38 and the control sleeve 50 ensures that through this game and the outlet passage 40, the control chamber 36 is filled with fuel very quickly as soon as - to end an injection process by closing the pilot valve 70, the control body 38 from its system on Drain chamber body 46 is moved away.
• the possible stroke of the control body 38 is preferably less; a stroke limiting shoulder 84 on the control sleeve 50 limits the maximum possible distance between the outlet space body 46 and the control body 38 to, for example, approximately 0.05-0.2 mm or 0.02-0.2 mm.
• the intermediate disk 86 can be exchanged in order to coordinate the behavior of the fuel injection valve 10 by selecting the desired thickness.
• FIGS. 3 to 6 the same reference numerals are used for the embodiment according to FIGS. 1 and 2 as in FIGS. 1 and 2. Only the differences between the embodiment shown in the figure and that according to the figures are shown below 1 and 2 explained.
• the high-pressure channel 58 In the embodiment shown in FIG. 3, only a single high-pressure channel 58 is provided, which is designed as an angular bore and opens coaxially to the longitudinal axis 16 from the drain chamber body 46.
• the high-pressure duct 58 As in the embodiment shown in FIGS. 2 and 3, opens into the annular space 60, which is connected to the high-pressure space 34.
• the recess 64 in the drain body 46 is annular formed so that a sealing surface running around the mouth of the high-pressure channel 58 and radially outside an annular sealing surface for cooperation with the control body 38 remains radially on the inside.
• the outlet passage 40 runs obliquely with respect to the longitudinal axis 16, so that it opens into the annular space formed by the recess 64.
• the drainage space 48 is also formed through a bore which is oblique with respect to the longitudinal axis 16 through the discharge space body 46, the drainage space 48 opening into the recess 64 on the one hand and the mouth of the drainage space 48 being arranged centrally on the side of the pilot valve 70 to the longitudinal axis 16.
• the pilot valve pin 76 is in turn mounted in the holding nut 54, on which the discharge space 72 is excluded, in a close sliding fit.
• the throttle passage 74 is formed on the pilot valve pin 66 by a blind hole made from the actuator side, which - instead of a single throttle point 9 '- by means of a radial first throttle bore 90 with the relief chamber 72 and a radial second throttle bore 90' with the low pressure outlet 76 in Flow connection is established.
• the diameter of these two throttle bores 90, 90 'can compared to the single throttle constriction 74' in the throttle passage 74 according to FIGS. 1 and 2, be chosen somewhat larger and thus somewhat less precise in order to achieve a corresponding throttling effect .mu.m.
• the cooperating with the pilot valve pin 66 end face of the Aktuatorschafts "78 is formed flat to to seal the blind hole in the pilot valve pin 68.
• control body 38 is designed similarly to that according to FIG. 2, but the throttle restriction 40 ′ of the outlet passage 40 is located in the end region facing the drainage space 48.
• the otherwise circular-cylindrical outlet passage 40 has a conical shape in its end area on the control chamber, in which the opposite end area of the injection valve member 22 engages when the injection valve member 22 is in the maximum open position. This leads to a very good sealing of the outlet passage 40 and, upon completion of the injection process, contributes to a very rapid lifting of the control body 38 from the injection valve body 28 and thus a very fast closing movement of the injection valve member 22.
• 4 left and right of the longitudinal axis 16, two further possible embodiments for the high-pressure duct 58 are shown.
• the drain chamber body 46 in this embodiment is no longer mushroom-shaped but pill-shaped and is pressed by means of the holding nut 54 in sealing contact against the contact shoulder 56 of the valve housing 14. Furthermore, the relief space 72 is arranged inside the drain space body 46, on which the pilot valve pin 66 is also guided in a close sliding fit. In this case, the drain space body 46 also serves as a relief space body.
• the high-pressure chamber 34 is thus sealed off from the low-pressure outlet 76 by the sealing abutment of the discharge chamber body 46 against the contact shoulder 56.
• only these two interacting surfaces are to be designed with high precision, in contrast to the forms of embodiment according to FIGS. 1-3 , where the abutting end faces of the drain body 46 and the retaining nut 54 are to be formed as sealing surfaces.
• the pilot valve seat 68 and, subsequently, the relief chamber 72 are formed by a conical enlargement - seen from the control body 38 - of the bore forming the drain chamber 48. Is accordingly opposite that part of the pilot valve pin 66 which cooperates with the pilot valve seat 68 is conical.
• the relief space 72 in turn runs as an annular space around the pilot valve pin 66 and the throttle passage 74 is designed as an oblique bore in the pilot valve pin 66 with respect to the longitudinal axis 16, but now - in contrast to the embodiment according to FIGS. 1 and 2 - the throttle restriction 74 'is in the End region of the throttle passage 44 facing the low-pressure outlet 76. From a hydraulic point of view, the volume of the throttle passage 74 upstream of the throttle restriction 74 ′ is therefore part of the relief space 72.
• the retaining nut 54 is designed to be tightened with a hexagon socket, which at the same time surrounds the pilot valve pin 66 at a distance in order to form the flow connection between the throttle passage 74 and the low-pressure outlet 76.
• FIG. 5 shows an embodiment very similar to that of FIG. 3, the drain chamber body 46 no longer being mushroom-shaped but pill-shaped.
• the annular space 60 extends around the upper end region of the control sleeve 50.
• the high-pressure duct 58 is formed by two bores running obliquely to one another and to the longitudinal axis 16. One opens into the annular space 60 and the other into the center of the end face 46 'of the discharge space body 46.
• the throttle restriction 40' of the outlet passage 40 is located at the recess 64, which is integrally formed on the control body 38 is.
• Drain chamber body 46 is pill-shaped and does not have a high pressure channel 58 in the center of the drain chamber 48 running in the axial direction.
• the pilot valve pin 66 which is designed as shown in FIGS. 1 and 2, interacts with the drain chamber body 46.
• the control body 38 is in the form of a spool valve body 'in the control sleeve 50 microns in a close sliding fit of approximately 2 out microns to 10th
• the annular space 60 which is recessed radially on the inside of the control sleeve 50 and which is connected to the high-pressure space 34 via a radial passage and the longitudinal groove 62, runs around its end region facing the drain space body 46.
• the outlet passage 40 runs through the control body 38 concentrically to the longitudinal axis 16.
• Throttle restriction 40 'at the end facing the control chamber 36. Parallel to this, but radially offset with respect to the longitudinal axis 16, a connecting channel 94 runs through the control body 38 and is closed when the control body 38 abuts the drain chamber body 46.
• the connecting channel 94 connects the control chamber 36 to the high-pressure chamber 34.
• the connecting channel 94 has the same function as the radial play between the control body 38 and the control sleeve 50 in the embodiments shown above formed on the control body 38, on its end face 42, inner and outer recesses 64, which serve to make the surface with which the control body 38 lies sealingly against the discharge chamber body 46, in order to achieve a high surface pressure. Furthermore, through a more or less large radially outer recess 64 the dynamic behavior of the control body 38 with respect to lifting off from contact with the discharge space body 46 can be varied.
• FIG. 7 shows an embodiment of the fuel injection valve 10 according to the invention, in which the control body 38 is replaced by a leaf spring 96.
• the leaf spring 96 is similar to that of the leaf spring known from EP-A-1 273 791.
• a C or U-shaped slot is cut out of a spring steel disk and separates a radially inner leaf spring tongue 98 from a retaining ring 100.
• the leaf spring 96 is held with its retaining ring 100 between the control sleeve 50 and the drain chamber body 46.
• the retaining ring 100 and the control sleeve 50 are jointly encompassed by a centering ring 102.
• the throttle constriction 40 ′ is formed on the leaf spring tongue 98, concentrically to the longitudinal axis 16, as a through hole.
• the leaf spring tongue 98 when it bears against the drain chamber body 46, closes off both the high-pressure channel 58 formed therein and the drain chamber 48 running centrally to the longitudinal axis 16.
• a throttle inlet 92 which connects the high-pressure chamber 34 to the outlet chamber 48, can be excluded on the leaf spring 96.
• the effect of this throttle approval 92 is the same as that of the throttle passage 92 of the embodiment according to FIGS. 3 and 8, namely especially when using an electromagnetic
• the drain chamber body 46, the holding nut 54 with the relief chamber 72 and the pilot valve pin 66 with the first and second throttle bores 90, 90 ', and the actuator 18 with its actuator shaft 78 are of the same design as in the embodiment 3.
• the control body 38 is now mushroom-shaped and its trunk is guided in a blind hole-like recess of the injection valve member 22 in the direction of the longitudinal axis 16.
• the compression spring 44 is supported on the one hand on the bottom of this blind hole and on the other hand on the stem of the control body 38.
• the control sleeve 50 delimits the control chamber 36, engages around the hat of the control body 38 at a radial distance and lies with its end face sealingly against the end face 46 'of the drain chamber body 46.
• the throttle restriction 40 ′ is formed on the hat of the mushroom-shaped control body 38. It communicates with the annular recess 64 on the discharge chamber body 46 and is thus in flow communication with the drain chamber 48. For the sake of completeness, it should be added that there is a radial play between the stem of the mushroom-shaped control body 38 and the injection valve member 22 in order to achieve rapid pressure equalization between the control chamber 36 and the space in which the compression spring 44 is arranged.
• the actuator 18 pulls the actuator shaft 78 upward in the axial direction, that is to say in the direction away from the pilot valve seat 68. Since there is high pressure in the discharge space 48, the pilot valve pin .66 is lifted off the pilot valve seat 68 in accordance with the movement of the actuator shaft 78. This leads to a very rapid pressure increase in the relief space 72 and a correspondingly rapid pressure reduction in the discharge space 48 and in the outlet passage 40 downstream of the throttle restriction 40 '.
• the fuel flows from the relief chamber 72 through the throttle passage 74 to the low-pressure outlet 76 in a damped manner.
• the throttled constriction 40 ′ dampens the fuel from the control chamber 36. This leads to a pressure reduction in the control chamber 36, as a result of which the injection valve member 22 is known is lifted off the injection valve seat 26.
• the pilot valve pin 66 is moved very quickly downward into contact with the pilot valve pin 66 by means of the actuator 18, and the pilot valve 70 is thereby closed. Since the pilot valve seat 68 dips very quickly into the relief space 72, there is an increase in pressure Generated, which propagates through the drain chamber 48 and leads to the lifting of the control body 38, or the leaf spring tongue 98, from the drain chamber body 46, since a rapid pressure equalization in the control chamber 36 can not take place because of the throttle restriction 40 '. By lifting the control body 38, the entire end face 42 of the control body 38 is immediately subjected to fuel under high pressure, since the high-pressure channel 58 or the high-pressure channels 58 are opened.
• the fuel injection valve 10 according to the invention has a pilot valve 70, the losses in fuel caused thereby are small, since during the period in which the pilot valve 70 is open, in the embodiment according to FIGS. 1, 2, 4, 5 and 6 there is no hydraulic Connection between the drainage space 48 and the high pressure chamber 34.
• a throttle passage 92 is present; however, because of the very small cross section, the throttle passage 92 prevents a large amount of fuel from being drained off quickly.
• Piezoelectric and magnetostrictive actuators are therefore particularly suitable for fuel injection valves 10 according to the invention because they can exert very large forces, so that the pressure increase mentioned practically does not delay the movement of the pilot valve pin 66.
• the aforementioned actuators 18 have a faster switching behavior than electromagnets, they can also be used. The desired pressure increase can thus be achieved by designing the diameter and the stroke of the pilot valve pin 66.
• FIG. 9 has, in addition to the advantages shown in connection with the embodiments according to FIGS. 1 to 8, an increased ability for multiple injections in very short time intervals.
• the same reference numerals are used for parts having the same effect in the description of FIG. 9 as in connection with FIGS. 1 to 8.
• the pilot valve pin 66 is guided in the holding nut 54 in a close sliding fit.
• the discharge space 72 is formed by a recess on the holding nut 54 and it is through the throttle point 74 'and the throttle passage 74 in the retaining nut 54 permanently connected to the low-pressure chamber, in the same way as indicated in dashed lines in FIG. 2.
• the pill-shaped drain chamber body 46 lies sealingly. It has a central axial passage, which forms the discharge space 48.
• the end face of the discharge space body 46 facing the retaining nut 54 forms the planar pilot valve seat 68 which interacts with the pilot valve pin 66.
• the pilot valve pin 66 and the pilot valve seat 68 form the pilot valve controlled by an actuator 18 70, which separates the discharge space 48 from the discharge space 72 in the closed state.
• the drainage space 48 is formed by a central bore which widens in a funnel shape in the direction of the control body 38.
• This drain chamber 48 is penetrated by a transmission pin 104 whose diameter is smaller than the diameter of the cylindrical part of the drain chamber 48 and whose length is greater than the thickness of the drain chamber body 46 measured in the direction of the longitudinal axis 16.
• the transmission pin 104 thus projects the drain chamber body 46 on the side facing away from the holding nut 54 and facing the control body 38.
• the high-pressure channel 58 is formed on the drain chamber body 46, which has a radial blind hole and one from the end face 46 'of the drain chamber body 46 in Axial direction in the blind hole leading through hole is formed.
• the high-pressure channel 58 opens at the end face 46 'at a distance from ⁇ brawraum 48 so that the control body 38, when in contact with the end face 46', closes the mouth of the high-pressure channel 58th
• the drain chamber body 46, with its end face 46 ′ and the control body 38 in turn forms an intermediate valve 52.
• the intermediate body 50' is cup-shaped, the bottom facing the drain chamber body 46, and a pressure spring 44 being located inside the control body 38, which holds the control body 38 in contact with the bottom of the transmission pin 104 when the pilot valve 70 is open.
• the outlet passage 40 runs through the bottom of the control body 38 and is designed without a throttle restriction 40 ′ and communicates with the drainage space 48 when the control body 38 bears against the end face 46 ′. If the control body 38 rests on the end face 46 ', it closes the mouth of the high-pressure duct 58.
• the bottom of the control body 38 is at a distance from the end face 46 ′, which is given by the difference in length between the transmission pin 104 and the thickness of the drain chamber body 46.
• the stroke of the pilot valve pin. 66 is at least as large> • but preferably larger than this distance.
• the compression spring 44 is supported with its end facing away from the bottom of the control body 38 on an end face of a control chamber body 50 ′′, which with its end face lies sealingly against the intermediate body 50 ′.
• the control chamber body 50 ′′ delimits the control chamber 36 on the circumference, which is also delimited by the injection valve member 22, which is guided on the control chamber body 50 ′′ in a tight sliding fit.
• the injection valve member 22 is desaxed with respect to the common longitudinal axis 16. However, the control chamber 36 is continuously in flow connection with the interior of the cup-shaped control body 38 and the drain chamber 48.
• control chamber body 50 ′′ and the holding nut 54 are braced against one another so that the holding nut 54 bears tightly against the discharge chamber body 46, the latter on the other hand on the intermediate body 50 ′, and this in turn on the control chamber body 50 ′′.
• the intermediate body 50 'and control chamber body 50' can, like the control sleeve 50 in the other exemplary embodiments, be formed in one piece together. It is also conceivable to form the control chamber body 50" together with the injection valve seat body 28 or the valve housing 14 in one piece.
• An annular groove 106 open to the end face 46 ' can be formed in the drain chamber body 46, into which the high pressure channel 58 opens and which is closed by the latter when the control body 38 bears against the end face 46'.
• control body 38 it is also conceivable to make the control body 38 shorter, as seen in the direction of the longitudinal axis 16, so that the
• control body 38 is designed as a disk with an outlet passage 40 and the compression spring 44 designed as a helical spring is replaced by a plate spring or wave spring.
• a coaxial arrangement of the injection valve member 22 with the longitudinal axis 16 is also conceivable, the compression spring 44 being supported, for example, on the end face of the control chamber body 50 ′′ or on a support shoulder formed thereon.
• an annular gap is present between the transmission pin 104 and the drain space body 46.
• mount the transmission pin 104 in a sliding fit on the drain chamber body 46 and to make grindings on the transmission pin 104 in order to ensure the flow connection between the drain chamber 48 and the relief chamber 72 when the pilot valve 70 is open.
• pilot valve pin 66 can have a shoulder which interacts with the holding nut 54 in order to limit the stroke of the pilot valve pin 66 in the opening direction of the pilot valve 70.
• the fuel injection valve 10 shown in FIG. 9 functions as follows.
• the pilot valve 70 is closed.
• the control body 38 is raised from the end face 46 ′ of the drain chamber body 46, as a result of which the drain chamber 48 and the control chamber 46 are connected to the high pressure inlet 12 via the high pressure channel 58.
• the injection valve member 22 is in contact with the injection valve seat 26 in the closed position; see also FIG. 1.
• the actuator 18 pulls back the actuator shaft 78, as a result of which the pilot valve pin 66 moves away from the pilot valve seat 68 and the drain chamber 48 and thus the control chamber 36 are connected to the discharge chamber 72.
• the pilot valve pin 66 is made known by means of the actuator 18
• the transmission pin 104 is moved in the direction against the control body 38, which inevitably lifts off from the end face 46 '.
• the intermediate valve 52 opens and a connection is established between the control chamber 36 and the high pressure channel 58
• Discharge space 72 is supported.
• the injection valve member 22 is thus brought very quickly into contact with the injection valve seat 26, as a result of which the injection process is ended.
• control body 38 moves with the transmission pin 104 and thus with the pilot valve pin 66, the high-pressure channel 58 is closed or opened very quickly by the control body 38, which is the case with several Injections in short to very short time intervals is of great advantage.

Landscapes

• 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 (2)

Publications (2)

Family

ID=34200992

Family Applications (1)

Country Status (4)

Cited By (5)

Families Citing this family (23)

Family Cites Families (3)

• 2004
  • 2004-07-30 DE DE502004008540T patent/DE502004008540D1/de not_active Expired - Lifetime
  • 2004-07-30 EP EP04738118A patent/EP1656498B1/fr not_active Expired - Lifetime
  • 2004-07-30 WO PCT/CH2004/000478 patent/WO2005019637A1/fr not_active Ceased
  • 2004-07-30 AT AT04738118T patent/ATE415554T1/de active

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events