WO1996000348A1 - Valve needle with filter element - Google Patents

Valve needle with filter element Download PDF

Info

Publication number
WO1996000348A1
WO1996000348A1 PCT/DE1995/000742 DE9500742W WO9600348A1 WO 1996000348 A1 WO1996000348 A1 WO 1996000348A1 DE 9500742 W DE9500742 W DE 9500742W WO 9600348 A1 WO9600348 A1 WO 9600348A1
Authority
WO
WIPO (PCT)
Prior art keywords
valve
valve needle
filter element
fuel
section
Prior art date
Application number
PCT/DE1995/000742
Other languages
German (de)
French (fr)
Inventor
Peter Romann
Ferdinand Reiter
Martin Maier
Manfred Dreyer
Original Assignee
Robert Bosch Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Publication of WO1996000348A1 publication Critical patent/WO1996000348A1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/02—Actuating devices; Operating means; Releasing devices electric; magnetic
    • F16K31/06—Actuating devices; Operating means; Releasing devices electric; magnetic using a magnet, e.g. diaphragm valves, cutting off by means of a liquid
    • F16K31/0644—One-way valve
    • F16K31/0655—Lift 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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/06—Injectors peculiar thereto with means directly operating the valve needle
    • F02M51/061—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means
    • F02M51/0625—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures
    • F02M51/0664—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding
    • F02M51/0667—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding the armature acting as a valve or having a short valve body attached 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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/06—Injectors peculiar thereto with means directly operating the valve needle
    • F02M51/061—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means
    • F02M51/0625—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures
    • F02M51/0664—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding
    • F02M51/0671—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding the armature having an elongated valve body attached 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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/06—Injectors peculiar thereto with means directly operating the valve needle
    • F02M51/061—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means
    • F02M51/0625—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures
    • F02M51/0664—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding
    • F02M51/0671—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding the armature having an elongated valve body attached thereto
    • F02M51/0682—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding the armature having an elongated valve body attached thereto the body being hollow and its interior communicating with the fuel flow
    • 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
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/165—Filtering elements specially adapted in fuel inlets to injector
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/02—Actuating devices; Operating means; Releasing devices electric; magnetic
    • F16K31/06—Actuating devices; Operating means; Releasing devices electric; magnetic using a magnet, e.g. diaphragm valves, cutting off by means of a liquid
    • F16K31/0644—One-way valve
    • F16K31/0651—One-way valve the fluid passing through the solenoid coil

Definitions

  • the invention is based on a valve needle according to the main claim. It is already known from DE-OS 40 03 228 a valve needle formed from an armature, a valve needle section and a valve closing body as an actuating part for opening and closing a fuel injection valve, in which, among other things, a fuel filter at the inlet end of the fuel injection valve valve is pressed into the fuel inlet connector.
  • the fuel filter ensures that those fuel components are filtered out which, because of their size, could cause blockages or damage in the injection valve.
  • This fuel filter is provided on the circumference, for example with a brass ring, which forms the pairing with the wall of the fuel inlet connection when the fuel filter is pressed in.
  • a disadvantage of this method is the occurrence of abrasion and shavings, which can be detached when pressed in due to the interference fit between the fuel filter and the fuel inlet connector, which simultaneously serves as a core, and then cause contamination in the injection valve.
  • Contamination inside the injection valve can also occur when inserting an adjusting sleeve into the flow bore of the core, due to wear of the abutment surfaces of the core and armature, or due to production-related burrs on various components of the injection valve arise.
  • This built-in or shaken-off dirt inside the injection valve cannot be prevented by the fuel filter at the inlet end of the fuel injection valve. As a result, in the most extreme case, blockages or leaks at the valve seat can occur, so that the injection valve is no longer fully functional.
  • valve needle according to the invention with the characterizing features of the main claim has the advantage that dirt which has been built in or formed in the interior of the injection valve is kept away from the valve seat, so that no effects of these particles on the
  • Leakage of the injection valve occurs in the area of the valve seat and blockages on the valve seat are excluded.
  • This is advantageously achieved in that a filter element integrated in or on the valve needle is provided in the injection valve, which keeps all particles and contaminants upstream of the valve seat in the interior of the injection valve away from the valve seat by being deposited on the filter element and thus the mentioned blockage ⁇ prevents valve seat.
  • FIG. 1 shows a fuel injection valve with a valve needle according to the invention
  • FIG. 2 shows a first exemplary embodiment of this valve needle
  • FIG. 3 4 shows a section along the line IV-IV in FIG. 3
  • FIG. 5 shows a third embodiment of a valve needle
  • FIG. 6 shows a section along the line VI-VI in FIG. 5
  • FIG. 7 shows a plan view of a valve needle according to FIG a fourth
  • FIG. 8 shows a section along the line VIII-VIII in FIG. 7
  • FIG. 9 shows a section along the line IX-IX in FIG. 8
  • FIG. 10 shows a section along the line XX in FIG. 8
  • FIG. 11 shows a fifth exemplary embodiment of a Valve needle.
  • the electromagnetic actuatable valve shown in FIG. 1, for example, in the form of an injection valve for fuel injection systems of mixture-compressing, spark-ignited internal combustion engines has a tubular core 2, which is surrounded by a magnetic coil 1 and serves as a fuel inlet connection and has a constant outer diameter, for example, over its entire length having.
  • a coil body 3 which is stepped in the radial direction, receives a winding of the magnetic coil 1 and, in conjunction with the core 2, enables a compact construction of the injection valve in the area of the magnetic coil 1.
  • a tubular metal intermediate part 12 is tightly connected concentrically to a longitudinal valve axis 10, for example by welding, and thereby partially surrounds the core end 9 axially.
  • the stepped coil body 3 overlaps the core 2 and the intermediate part 12 at least partially axially.
  • a tubular valve seat carrier 16 extends downstream of the coil body 3 and the intermediate part 12 and is, for example, firmly connected to the intermediate part 12.
  • a longitudinal bore 17 runs in the valve seat support 16 and is formed concentrically with the valve longitudinal axis 10.
  • a valve needle 18 according to the invention is arranged with, for example, tubular valve needle section 19, which is designed together with a filter element 20, for example in the form of a sieve stocking.
  • a spherical valve closing body 24 is provided, on the circumference of which, for example, five flats 25 are provided for the fuel to flow past and which is connected, for example by welding, to the tubular valve needle section 19.
  • the injection valve is actuated in a known manner, for example electromagnetically.
  • the electromagnetic circuit with the magnetic coil 1, the core 2 and an armature 27 is used for the axial movement of the valve needle 18 and thus for opening against the spring force of a return spring 26 or closing the injection valve.
  • the armature 27 is at the end facing away from the valve closing body 24 of the valve needle section 19 connected by a weld seam and aligned with the core 2.
  • a cylinder-shaped valve seat body 29, which has a fixed valve seat 30, is tightly mounted by welding.
  • a guide opening 32 of the valve seat body 29 serves to guide the valve closing body 24 during the axial movement of the valve needle 18 with the armature 27 along the valve longitudinal axis 10 together.
  • the valve seat body 29 On its end face remote from the valve closing body 24, the valve seat body 29 is provided with, for example Cup-shaped spray hole disk 34 is connected concentrically and firmly, for example by an all-round tight weld seam, for example formed by a laser. At least one, for example four, spray openings 39 formed by erosion or stamping are provided in the, for example, pot-shaped spray perforated disk 34.
  • a protective cap 43 is arranged on the periphery of the valve seat carrier 16 at its downstream end facing away from the core 2 and is connected to the valve seat carrier 16, for example, by means of a catch.
  • the insertion depth of the valve seat body 29 with the spray orifice plate 34 determines the presetting of the stroke of the valve needle 18.
  • the one end position of the valve needle 18 when the solenoid coil 1 is not excited is due to the contact of the
  • Valve closing body 24 fixed to the valve seat 30 of the valve seat body 29, while the other end position of the valve needle 18 results when the solenoid coil 1 is excited due to the armature 27 resting on the core end 9.
  • the magnet coil 1 is surrounded by at least one guide element 45, for example designed as a bracket and serving as a ferromagnetic element, which at least partially surrounds the magnet coil 1 in the circumferential direction and rests with its one end on the core 2 and its other end on the valve seat support 16 and can be connected to it, for example, by welding, soldering or gluing.
  • at least one guide element 45 for example designed as a bracket and serving as a ferromagnetic element, which at least partially surrounds the magnet coil 1 in the circumferential direction and rests with its one end on the core 2 and its other end on the valve seat support 16 and can be connected to it, for example, by welding, soldering or gluing.
  • An adjusting sleeve 48 inserted into a flow bore 46 of the core 2 concentric to the longitudinal valve axis 10 serves to adjust the spring preload of the return spring 26 resting on the adjusting sleeve 48, which in turn is supported with its opposite side on the valve needle section 19.
  • the injection valve is largely enclosed with a plastic encapsulation 50, which extends from the core 2 in the axial direction via the magnet coil 1 and the at least one guide element 45 to the valve seat support 16, the at least one guide element 45 being completely covered axially and in the circumferential direction .
  • This plastic encapsulation 50 includes, for example, an injection molded electrical connector 52.
  • the injection valve can have a fuel filter 55.
  • the fuel filter 55 then protrudes into the flow bore 46 of the core 2 at its inlet side, the end 56 facing away from the spray orifice plate 34. The one entering the fuel injector
  • the fuel filter 55 ensures that particles carried in the fuel are filtered out which, because of their size or chemical composition, could cause blockages or damage in the injection valve.
  • the fuel filter 55 can be mounted, and in the assembled state it rests, for example, with a retaining ring 58 with a slight radial pressure on the wall of the flow bore 46.
  • the filter fabric of the fuel filter 55 is fastened in a cup-shaped carrier part 60 made of plastic with, for example, three axial webs 61.
  • the filter element 20 is provided on the valve needle 18 designed according to the invention.
  • the filter element 20 In the assembled state of the injection valve, the filter element 20 is integrated in or on the valve needle 18. From a manufacturing point of view, however, it makes sense to to produce element 20 separately from the individual components of valve needle 18. The pushing on, inserting or other options for attaching the filter element 20 in or on the valve needle 18 are explained in more detail below.
  • the filter element 20 arranged in or on the valve needle 18 has the function of keeping all particles and contaminants upstream of the valve seat 30 in the interior of the injection valve away from the valve seat 30 and thus preventing blockages or leaks at the valve seat 30.
  • Contamination in the interior of the injection valve can occur, for example, when inserting the adjusting sleeve 48, when the fuel filter 55 is pressed in, due to wear on the abutment surfaces of the core 2 and armature 27 or as a result of production-related burrs on various components of the injection valve.
  • the filter element 20 for example made of a conventional polyamide fabric as a screen fabric 62, is drawn in the form of a screen stocking without a plastic reinforcement over the valve needle section 19 and completely surrounds it radially over the entire axial extension length.
  • the sieve stocking is, for example, with an axially running seam 63 on the
  • FIGS. 2 to 11 show different exemplary embodiments of filter elements 20 integrated in or on valve needle 18. The representation of the entire injection valve is omitted in these figures, since this is shown in FIG. 1 Fuel injection valve is intended only as an example for possible uses of filter elements 20 and therefore other series of valves, especially injection valves, can also be equipped with the valve needles 18 according to the invention. Compared to the embodiment shown in FIG. Example of the same or equivalent parts of the valve needle 18 are also identified in FIGS. 2 to 11 by the same reference numerals.
  • Filter element 20 according to the exemplary embodiment shown in FIG. 1 is shown again in FIG. 2. Without a plastic reinforcement in the form of a carrier body, the filter element 20 is pulled over the valve needle section 19 and surrounds it completely radially. In addition to the welding (seam 63) already mentioned, slipping of the filter element 20 is also ruled out in that the armature 27, as a part firmly connected to the valve needle section 19, for example by welding, also engages around the screen fabric 62 and between it and the valve needle section 19 clamps.
  • FIGS. 3 and 4 show a second exemplary embodiment of a valve needle 18 with a filter element 20 attached to the outer circumference of the valve needle section 19.
  • the sleeve-shaped filter element 20, which is shown in section in FIG. 3, is now similar to the fuel filter 55 det, ie consisting of a carrier body 64 made, for example, of plastic and the actual screen fabric 62, for example a polyamide fabric.
  • the screen fabric 62 is also molded, for example, during the manufacture of the carrier body 64.
  • the carrier body 64 is surrounded by a circumferential ring section 67, which extends away from the valve closing body 24, and by, for example, three axial webs 65 which run in the axial direction and are offset by 120 ° on the circumference of the filter element 20 and which serve as the sieve fabric 62 minimal cover, formed.
  • the axial webs 65 thus extend from the ring section 67 to directly to the valve closing body 24.
  • FIG. 4 as a sectional illustration of a section along the line IV-IV in FIG. 3 again illustrates the arrangement of the axial webs.
  • ge 65 which have only a small width and thus only cover the fuel outlet openings in the valve needle section 19 to a small extent even in an unfavorable position.
  • the ring section 67 is designed such that it can overlap a collar 70 existing at the downstream end of the armature 27 and thus there is a latching between the carrier body 64 and the armature 27, which prevents the filter element 20 from slipping.
  • the filter element 20 is therefore completely outside of the actual valve needle 18.
  • the filter element 20 is pushed into the tubular valve needle section 19.
  • the filter element 20 has a largely similar shape to the filter element 20 shown in FIGS. 3 and 4. It therefore also consists of a carrier body 64 made of plastic and the sieve fabric 62.
  • the carrier body 64 has a bottom 72 facing the valve closing body 24, a circumferential ring section 67 facing away from the valve closing body 24 and two or three axially extending between the ring section 67 and the bottom 72 and 180 ° or 120 ° on the circumference of the filter element 20 offset axial webs 65.
  • Screen fabric 62 is, for example, also molded on during the manufacture of the carrier body 64. While the bottom 72 completely closes the inner diameter of the valve needle section 19 between the fuel outlet openings and the valve closing body 24 and can thus serve to deposit the particles and impurities, the ring section 67 represents an open cross section so that the fuel is unhindered can flow into the valve needle section 19.
  • the filter element 20 is thus cup-shaped.
  • the ring portion 67 has, for example, such an outer diameter that an interference fit in Valve needle section 19 is present, so that a very simple type of fastening is guaranteed, the force of a human finger being completely sufficient to insert the filter element 20.
  • FIG. 6, which shows a section along the line VI-VI in FIG. 5, illustrates the arrangement of the, for example, three axial webs in the interior of the valve needle section 19.
  • an actuating part consisting of the valve needle section 19 and the armature 27, which is produced in one piece by the so-called metal injection molding method (MIM), is shown in section.
  • the method already known, inter alia, from DE-PS 42 30 376 comprises the production of molded parts from a metal powder with a binder, for example a plastic binder, for example on conventional plastic injection molding machines and the subsequent removal of the binder and sintering remaining metal powder structure.
  • the valve closing body 24 is then firmly and tightly connected to the valve needle section 19, for example by means of a welded connection at the downstream end of the actuating part.
  • a valve needle 18, in which at least the actuating part consisting of valve section 19 and armature 27 is formed in one piece as a MIM part and valve needle section 19 represents a solid part, has already been proposed in German patent application DE-P 44 15 850.5.
  • FIG. 7 shows a plan view of the valve needle 18 or the armature 27 from an upstream end face 74 facing the core 2.
  • a holding shoulder 75 which is axially lower than the end face 74 and has a smaller diameter than the end face 74, for supporting the return spring 26 by, for example, three or four axial grooves running in the direction of the valve longitudinal axis 10 76 is interrupted.
  • the axial grooves 76 extend over the entire remaining length of the armature 27 and serve to allow the fuel coming from the flow bore 46 of the core 2 to flow unhindered in the direction of the valve seat 30.
  • FIG. 8 is an illustration of a section along the line VIII-VIII in FIG. 7, the section being carried out in such a way that it runs both through the solid material from the holding shoulder 30 in the axial direction of the armature 27 and through an axial groove 76 in the armature 27.
  • the valve needle section 19 projects partially into the armature 27, that is to say that an upstream end face 77 of the valve needle section 19 facing the holding shoulder 30 lies further upstream than a shoulder 78 resulting on the outer contour of the actuating part from armature 27 to valve needle section 19, at which the axial grooves 76 end.
  • the axial grooves 76 no longer represent grooves, but instead, due to the complete encapsulation of the material, axial flow channels 80 adjoining one another in alignment.
  • the fuel occurs in the area of the shoulder 78 from the flow channels 80 at least partially as a wall film of the valve needle section 19, since the inner boundary of each flow channel 80 is given by the valve needle section 19.
  • paragraph 78 the
  • the sleeve-shaped filter element 20 is fastened to the valve needle section 19, for example, in a manner similar to the embodiment shown in FIGS. 3 and 4.
  • the valve needle section 19 as a section of the actuating part produced by means of the MIM method has, for example, four latching lugs 82 on its circumference axially close to the shoulder 78, which are each offset on the valve needle section 19 by 90 °.
  • These latches 82 can now encompass a carrier body 64 made of plastic of the filter element 20, with which a secure fixation of the filter element 20 on the valve needle 18 is guaranteed.
  • Flow spaces 83 remain in the circumferential direction between the locking lugs 82 for the fuel flowing in via the flow channels 80, since the carrier body 64 with its upper ring section 85 has a larger inner diameter than the diameter of the valve needle section 19 between the locking lugs 82.
  • a lower ring section 86 also belongs to the carrier body 64, which forms the downstream end of the filter element 20.
  • the screen fabric 62 through which the fuel flows radially outward between the two ring sections 85 and 86, has also been molded on, for example, during the manufacture of the carrier body 64.
  • the two ring sections 85 and 86 can be connected to one another by axial webs or can also be separate from one another if only the screen fabric 62 is to be present between the two ring sections 85 and 86.
  • FIGS. 9 and 10 are representations of sections along lines IX-IX and XX in FIG. 8 through the upper ring section 85 of the carrier body 64 of the filter element 20.
  • the formation of the latching lugs 82 which are in each case, becomes particularly clear Extend radially outwards from the circumference of the valve needle section 19 by 90 ° and thus offer the possibility of locking the carrier body 64.
  • the inner opening of the ring section 85 of the carrier body 64 is not circular, but with different areas of larger and smaller opening width.
  • four recesses 88 are provided in the ring section 85, for example, into which the locking lugs 82 engage.
  • the flow spaces 83 formed between two locking lugs 82 have their greatest width exactly in the middle between two locking lugs 82, since the valve needle section 19 has a circular cross section and the inner opening of the ring section 85 has a largely square cross section.
  • a circle arranged centrally in a square always has the greatest distance from the corner points of the square, which are therefore exactly in the middle between two locking lugs 82.
  • the fuel comes from the axial grooves 76 via the flow channels 80 in the armature 27 directly into the flow spaces 83 and then exits the filter element 20 radially through the screen fabric 62 in the direction of the valve seat 30. Particles entrained in the fuel can be deposited in a wedge opening 89 of the lower ring section 86, which is slightly wedge-shaped toward the valve needle 18.
  • a filter element 20 in the form of a plate spring.
  • the actuating part consisting of armature 27 and valve needle section 19 is, for example, formed in one piece and has at least one flow channel 80 running in armature 27, which ends at armature 27 from armature 27 to valve needle section 19, resulting on the outer contour of the actuating part, with which the fuel can reach valve seat 30 directly.
  • the filter element 20 is therefore located between the end of the flow channel 80 at the shoulder 78 and the valve seat 30.
  • the filter element 20 therefore has only two circumferential retaining rings 90, 91, which have a very small cross-section and are made of plastic or metal, which have a different diameter and clamp the screen fabric 62 between them.
  • the sieve fabric 62 tapers downstream in the shape of a truncated cone, since the retaining ring 91 facing the valve closing body 24 has a smaller one The diameter is that of the retaining ring 90 facing away from the valve closing body 24.
  • the retaining rings 90 and 91 of the filter element 20 are accommodated in ring receiving grooves 92 provided for this purpose on the shoulder 78 of the armature 27 and on the valve needle section 19. By clipping or pressing in the retaining rings 90 in the ring receiving grooves 92 (press fit) a sufficiently secure fit is guaranteed.
  • filter elements 20 can be used on a wide variety of valve needles 18 of valves, especially of injection valves, also on valve needles which are not explained in more detail here.

Abstract

In prior art fuel-injection valves, fuel filters are inserted into the fuel-inlet pipe where they are secured in place. These fuel filters ensure that certain constituants which could, by virtue of their particle size, block or damage the valve are filtered out of the fuel fed to the valve. Foreign bodies inside the valve which originate from components inserted into the valve, from wear of stop surfaces or from production-related burring are not filtered out however, resulting in the danger of blockages or leakage at the valve seat. The valve needle (18) proposed, for a fuel-injection valve for instance, has a filter element (20) integrated in or on it. The function of this filter element (20) is to keep any particles or other impurities inside the valve upstream of the valve seat (30) away from the valve seat (30) and hence avoid blockages or leakage at the valve seat (30). The valve needle proposed is particularly suitable for use in injection valves in fuel-injection systems for mixture-compression external-ignition-combustion engines.

Description

Ventilnadel mit Filter.Valve needle with filter.
Stand der TechnikState of the art
Die Erfindung geht aus von einer Ventilnadel nach der Gat¬ tung des Hauptanspruchs. Es ist schon aus der DE-OS 40 03 228 eine aus einem Anker, einem Ventilnadelab¬ schnitt und einem Ventilschließkörper gebildete Ventilnadel als Betätigungsteil zum Öffnen und Schließen eines Brenn¬ stoffeinspritzventiles bekannt, bei dem u.a. ein Brenn¬ stoffilter am zulaufseitigen Ende des Brennstoffeinspritz- ventils in den Brennstoffeinlaßstutzen gepreßt ist. Der Brennstoffilter sorgt für die Herausfiltrierung solcher Brennstoffbestandteile, die aufgrund ihrer Größe im Ein¬ spritzventil Verstopfungen oder Beschädigungen verursachen könnten. Dieser Brennstoffilter ist am Umfang beispielsweise mit einem Messingring versehen, der mit der Wandung des Brennstoffeinlaßstutzens die Paarung beim Einpressen des Brennstoffilters bildet. Als nachteilig bei diesem Verfahren erweist sich ein eventuelles Entstehen von Abrieb und Spä¬ nen, die beim Einpressen aufgrund der Preßpassung zwischen Brennstoffilter und Brennstoffeinlaßstutzen, der gleichzei¬ tig als Kern dient, abgelöst werden können und dann für Ver¬ schmutzungen im Einspritzventil sorgen. Verunreinigungen im Inneren des Einspritzventils können ebenso beim Einschieben einer Einstellhülse in die Strömungsbohrung des Kerns, durch Verschleiß der Anschlagflächen von Kern und Anker bezie¬ hungsweise durch fertigungsbedingten Grat an verschiedenen Bauteilen des Einspritzventils auftreten beziehungsweise entstehen. Dieser eingebaute beziehungsweise losgeschüttelte Schmutz im Inneren des Einspritzventils kann durch den Brennstoffilter am zulaufseitigen Ende des Brennstoffein¬ spritzventils nicht verhindert werden. Als Folge dessen kann es im extremsten Fall zu Verstopfungen beziehungsweise Undichtheiten am Ventilsitz kommen, so daß das Einspritzven¬ til nicht mehr voll funktionstüchtig ist.The invention is based on a valve needle according to the main claim. It is already known from DE-OS 40 03 228 a valve needle formed from an armature, a valve needle section and a valve closing body as an actuating part for opening and closing a fuel injection valve, in which, among other things, a fuel filter at the inlet end of the fuel injection valve valve is pressed into the fuel inlet connector. The fuel filter ensures that those fuel components are filtered out which, because of their size, could cause blockages or damage in the injection valve. This fuel filter is provided on the circumference, for example with a brass ring, which forms the pairing with the wall of the fuel inlet connection when the fuel filter is pressed in. A disadvantage of this method is the occurrence of abrasion and shavings, which can be detached when pressed in due to the interference fit between the fuel filter and the fuel inlet connector, which simultaneously serves as a core, and then cause contamination in the injection valve. Contamination inside the injection valve can also occur when inserting an adjusting sleeve into the flow bore of the core, due to wear of the abutment surfaces of the core and armature, or due to production-related burrs on various components of the injection valve arise. This built-in or shaken-off dirt inside the injection valve cannot be prevented by the fuel filter at the inlet end of the fuel injection valve. As a result, in the most extreme case, blockages or leaks at the valve seat can occur, so that the injection valve is no longer fully functional.
Vorteile der ErfindungAdvantages of the invention
Die erfindungsgemäße Ventilnadel mit den kennzeichnenden Merkmalen des Hauptanspruchε hat demgegenüber den Vorteil, daß im Inneren des Einspritzventils eingebauter beziehungs¬ weise entstandener Schmutz vom Ventilsitz ferngehalten wird, so daß keinerlei Auswirkungen dieser Partikel auf dieIn contrast, the valve needle according to the invention with the characterizing features of the main claim has the advantage that dirt which has been built in or formed in the interior of the injection valve is kept away from the valve seat, so that no effects of these particles on the
Dichtheit des Einspritzventils im Bereich des Ventilsitzes auftreten und Verstopfungen am Ventilsitz ausgeschlossen sind. Dies wird in vorteilhafter Weise dadurch erreicht, daß ein in beziehungsweise an der Ventilnadel integriertes Fil- terelement im Einspritzventil vorgesehen ist, das alle Par¬ tikel und Verunreinigungen stromaufwärts des Ventilsitzes im Inneren des Einspritzventils vom Ventilsitz durch Ablagerung am Filterelement fernhält und damit die erwähnten Verstop¬ fungen am Ventilsitz verhindert.Leakage of the injection valve occurs in the area of the valve seat and blockages on the valve seat are excluded. This is advantageously achieved in that a filter element integrated in or on the valve needle is provided in the injection valve, which keeps all particles and contaminants upstream of the valve seat in the interior of the injection valve away from the valve seat by being deposited on the filter element and thus the mentioned blockage ¬ prevents valve seat.
Durch die in den Unteransprüchen aufgeführten Maßnahmen sind vorteilhafte Weiterbildungen und Verbesserungen der im Hauptanspruch angegebenen Ventilnadel möglich.The measures listed in the subclaims permit advantageous developments and improvements of the valve needle specified in the main claim.
Zeichnungdrawing
Ausführungsbeispiele der Erfindung sind in der Zeichnung vereinfacht dargestellt und in der nachfolgenden Beschrei¬ bung näher erläutert. Es zeigen Figur 1 ein Brennstoffein- spritzventil mit einer erfindungsgemäßen Ventilnadel, Figur 2 ein erstes Ausführungsbeispiel dieser Ventilnadel, Figur 3 ein zweites Ausführungsbeispiel einer Ventilnadel, Figur 4 einen Schnitt entlang der Linie IV-IV in Figur 3, Figur 5 ein drittes Ausführungsbeispiel einer Ventilnadel, Figur 6 einen Schnitt entlang der Linie VI-VI in Figur 5, Figur 7 eine Draufsicht auf eine Ventilnadel gemäß einem viertenExemplary embodiments of the invention are shown in simplified form in the drawing and are explained in more detail in the following description. FIG. 1 shows a fuel injection valve with a valve needle according to the invention, FIG. 2 shows a first exemplary embodiment of this valve needle, FIG. 3 4 shows a section along the line IV-IV in FIG. 3, FIG. 5 shows a third embodiment of a valve needle, FIG. 6 shows a section along the line VI-VI in FIG. 5, FIG. 7 shows a plan view of a valve needle according to FIG a fourth
Ausführungsbeispiel, Figur 8 einen Schnitt entlang der Linie VIII-VIII in Figur 7, Figur 9 einen Schnitt entlang der Linie IX-IX in Figur 8, Figur 10 einen Schnitt entlang der Linie X-X in Figur 8 und Figur 11 ein fünftes Ausführungs- beispiel einer Ventilnadel.8 shows a section along the line VIII-VIII in FIG. 7, FIG. 9 shows a section along the line IX-IX in FIG. 8, FIG. 10 shows a section along the line XX in FIG. 8, and FIG. 11 shows a fifth exemplary embodiment of a Valve needle.
Beschreibung der AusführungsbeispieleDescription of the embodiments
Das in der Figur 1 beispielsweise dargestellte elektromagne- tisch betätigbare Ventil in der Form eines Einspritzventils für Brennstoffeinspritzanlagen von gemischverdichtenden, fremdgezündeten Brennkraftmaschinen hat einen von einer Magnetspule 1 umgebenen, als Brennstoffeinlaßstutzen dienen¬ den rohrförmigen Kern 2, der beispielsweise über seine gesamte Länge einen konstanten Außendurchmesser aufweist.The electromagnetic actuatable valve shown in FIG. 1, for example, in the form of an injection valve for fuel injection systems of mixture-compressing, spark-ignited internal combustion engines has a tubular core 2, which is surrounded by a magnetic coil 1 and serves as a fuel inlet connection and has a constant outer diameter, for example, over its entire length having.
Ein in radialer Richtung gestufter Spulenkörper 3 nimmt eine Bewicklung der Magnetspule 1 auf und ermöglicht in Verbin¬ dung mit dem Kern 2 einen kompakten Aufbau des Einspritzven¬ tils im Bereich der Magnetspule 1.A coil body 3, which is stepped in the radial direction, receives a winding of the magnetic coil 1 and, in conjunction with the core 2, enables a compact construction of the injection valve in the area of the magnetic coil 1.
Mit einem unteren Kernende 9 des Kerns 2 ist konzentrisch zu einer Ventillängsachse 10 dicht ein rohrförmiges metallenes Zwischenteil 12 beispielsweise durch Schweißen verbunden und umgibt dabei das Kernende 9 teilweise axial. Der gestufte Spulenkδrper 3 übergreift den Kern 2 und das Zwischenteil 12 zumindest teilweise axial. Stromabwärts des Spulenkδrpers 3 und des Zwischenteils 12 erstreckt sich ein rohrförmiger Ventilsitzträger 16, der beispielsweise fest mit dem Zwi¬ schenteil 12 verbunden ist. In dem Ventilsitzträger 16 ver- läuft eine Längsbohrung 17, die konzentrisch zu der Ventil- längsachse 10 ausgebildet ist. In der Längsbohrung 17 ist eine erfindungsgemäße Ventilnadel 18 mit einem zum Beispiel rohrförmigen Ventilnadelabschnitt 19 angeordnet, der zusam¬ men mit einem Filterelement 20 zum Beispiel in der Form eines Siebstrumpfes ausgeführt ist. Am stromabwärtigen Ende 23 des Ventilnadelabschnitts 19 ist ein kugelförmiger Ven- tilschließkörper 24 vorgesehen, an dessen Umfang beispiels¬ weise fünf Abflachungen 25 zum Vorbeiströmen des Brennstoffs vorgesehen sind und der beispielsweise durch Schweißen mit dem rohrförmigen Ventilnadelabschnitt 19 verbunden ist.With a lower core end 9 of the core 2, a tubular metal intermediate part 12 is tightly connected concentrically to a longitudinal valve axis 10, for example by welding, and thereby partially surrounds the core end 9 axially. The stepped coil body 3 overlaps the core 2 and the intermediate part 12 at least partially axially. A tubular valve seat carrier 16 extends downstream of the coil body 3 and the intermediate part 12 and is, for example, firmly connected to the intermediate part 12. A longitudinal bore 17 runs in the valve seat support 16 and is formed concentrically with the valve longitudinal axis 10. In the longitudinal bore 17 a valve needle 18 according to the invention is arranged with, for example, tubular valve needle section 19, which is designed together with a filter element 20, for example in the form of a sieve stocking. At the downstream end 23 of the valve needle section 19, a spherical valve closing body 24 is provided, on the circumference of which, for example, five flats 25 are provided for the fuel to flow past and which is connected, for example by welding, to the tubular valve needle section 19.
Die Betätigung des Einspritzventils erfolgt in bekannter Weise zum Beispiel elektromagnetisch. Zur axialen Bewegung der Ventilnadel 18 und damit zum Öffnen entgegen der Feder¬ kraft einer Rückstellfeder 26 beziehungsweise Schließen des Einspritzventils dient der elektromagnetische Kreis mit der Magnetspule 1, dem Kern 2 und einem Anker 27. Der Anker 27 ist mit dem dem Ventilschließkörper 24 abgewandten Ende des Ventilnadelabschnitts 19 durch eine Schweißnaht verbunden und auf den Kern 2 ausgerichtet. Der den Anker 27 und den Ventilschließkörper 24 verbindende Ventilnadelabschnitt 19 bildet zusammen mit diesen beiden am stromaufwartigen und am stromabwärtigen Ende des Ventilnadelabschnitts 19 angeordne¬ ten Bauteilen beziehungsweise Abschnitten die Ventilnadel 18. In das stromabwärts liegende, dem Kern 2 abgewandte Ende des Ventilsitzträgers 16 ist in der Längsbohrung 17 ein zylinderfδrmiger Ventilsitzkörper 29, der einen festen Ven¬ tilsitz 30 aufweist, durch Schweißen dicht montiert.The injection valve is actuated in a known manner, for example electromagnetically. The electromagnetic circuit with the magnetic coil 1, the core 2 and an armature 27 is used for the axial movement of the valve needle 18 and thus for opening against the spring force of a return spring 26 or closing the injection valve. The armature 27 is at the end facing away from the valve closing body 24 of the valve needle section 19 connected by a weld seam and aligned with the core 2. The valve needle section 19 connecting the armature 27 and the valve closing body 24, together with these two components or sections arranged at the upstream and downstream ends of the valve needle section 19, forms the valve needle 18. In the downstream end of the valve seat carrier 16 facing away from the core 2 is shown in FIG the longitudinal bore 17, a cylinder-shaped valve seat body 29, which has a fixed valve seat 30, is tightly mounted by welding.
Zur Führung des Ventilschließkörpers 24 während der Axialbe- wegung der Ventilnadel 18 mit dem Anker 27 entlang der Ven¬ tillängsachse 10 dient eine Führungsδffnung 32 des Ventil¬ sitzkörpers 29. Der kugelförmige Ventilschließkörper 24 wirkt mit dem sich in Strömungsrichtung kegelstumpfförmig verjüngenden Ventilsitz 30 des Ventilsitzkörpers 29 zusam- men. An seiner dem Ventilschließkörper 24 abgewandten Stirn¬ seite ist der Ventilsitzkörper 29 mit einer beispielsweise topfförmig ausgebildeten Spritzlochscheibe 34 konzentrisch und fest, beispielsweise durch eine umlaufende dichte, zum Beispiel mittels eines Lasers ausgebildete Schweißnaht ver¬ bunden. In der zum Beispiel topfförmigen Spritzlochscheibe 34 sind wenigstens eine, beispielsweise vier durch Erodieren oder Stanzen ausgeformte Abspritzöffnungen 39 vorgesehen. Am Umfang des Ventilsitzträgers 16 ist an seinem stromabwärts liegenden, dem Kern 2 abgewandten Ende eine Schutzkappe 43 angeordnet und beispielsweise mittels einer Rastung mit dem Ventilsitzträger 16 verbunden.A guide opening 32 of the valve seat body 29 serves to guide the valve closing body 24 during the axial movement of the valve needle 18 with the armature 27 along the valve longitudinal axis 10 together. On its end face remote from the valve closing body 24, the valve seat body 29 is provided with, for example Cup-shaped spray hole disk 34 is connected concentrically and firmly, for example by an all-round tight weld seam, for example formed by a laser. At least one, for example four, spray openings 39 formed by erosion or stamping are provided in the, for example, pot-shaped spray perforated disk 34. A protective cap 43 is arranged on the periphery of the valve seat carrier 16 at its downstream end facing away from the core 2 and is connected to the valve seat carrier 16, for example, by means of a catch.
Die Einschubtiefe des Ventilsitzkörpers 29 mit der Spritz¬ lochscheibe 34 bestimmt die Voreinstellung des Hubs der Ven¬ tilnadel 18. Dabei ist die eine Endstellung der Ventilnadel 18 bei nicht erregter Magnetspule 1 durch die Anlage desThe insertion depth of the valve seat body 29 with the spray orifice plate 34 determines the presetting of the stroke of the valve needle 18. The one end position of the valve needle 18 when the solenoid coil 1 is not excited is due to the contact of the
Ventilschließkörpers 24 am Ventilsitz 30 des Ventilsitzkδr- pers 29 festgelegt, während sich die andere Endstellung der Ventilnadel 18 bei erregter Magnetspule 1 durch die Anlage des Ankers 27 am Kernende 9 ergibt.Valve closing body 24 fixed to the valve seat 30 of the valve seat body 29, while the other end position of the valve needle 18 results when the solenoid coil 1 is excited due to the armature 27 resting on the core end 9.
Die Magnetεpule 1 ist von wenigstens einem, beispielsweise als Bügel ausgebildeten und als ferromagnetisches Element dienenden Leitelement 45 umgeben, das die Magnetspule 1 in Umfangsrichtung wenigstens teilweise umgibt sowie mit seinem einen Ende an dem Kern 2 und seinem anderen Ende an dem Ven¬ tilsitzträger 16 anliegt und mit diesem zum Beispiel durch Schweißen, Löten beziehungsweise Kleben verbindbar ist.The magnet coil 1 is surrounded by at least one guide element 45, for example designed as a bracket and serving as a ferromagnetic element, which at least partially surrounds the magnet coil 1 in the circumferential direction and rests with its one end on the core 2 and its other end on the valve seat support 16 and can be connected to it, for example, by welding, soldering or gluing.
Eine in eine konzentrisch zur Ventillängsachse 10 verlaufen- de Strömungsbohrung 46 des Kerns 2 eingeschobene Einstell¬ hülse 48 dient zur Einstellung der Federvorspannung der an der Einstellhülse 48 anliegenden Rückstellfeder 26, die sich wiederum mit ihrer gegenüberliegenden Seite an dem Ventilna¬ delabschnitt 19 abstützt. Das Einspritzventil ist weitgehend mit einer Kunststoffum- spritzung 50 umschlossen, die sich vom Kern 2 ausgehend in axialer Richtung über die Magnetspule 1 und das wenigstens eine Leitelement 45 bis zum Ventilsitzträger 16 erstreckt, wobei das wenigstens eine Leitelement 45 vollständig axial und in Umfangsrichtung überdeckt ist. Zu dieser Kunststoff- umspritzung 50 gehört beispielsweise ein mitangespritzter elektrischer Anschlußstecker 52.An adjusting sleeve 48 inserted into a flow bore 46 of the core 2 concentric to the longitudinal valve axis 10 serves to adjust the spring preload of the return spring 26 resting on the adjusting sleeve 48, which in turn is supported with its opposite side on the valve needle section 19. The injection valve is largely enclosed with a plastic encapsulation 50, which extends from the core 2 in the axial direction via the magnet coil 1 and the at least one guide element 45 to the valve seat support 16, the at least one guide element 45 being completely covered axially and in the circumferential direction . This plastic encapsulation 50 includes, for example, an injection molded electrical connector 52.
Zusätzlich zu dem erfindungsgemäß an der Ventilnadel 18 vor¬ gesehenen Filterelement 20 kann das Einspritzventil einen Brennstoffilter 55 aufweisen. Der Brennstoffilter 55 ragt dann in die Strömungsbohrung 46 des Kerns 2 an dessen Zulaufseitigem, der Spritzlochscheibe 34 abgewandten Ende 56 hinein. Der in das Brennstoffeinspritzventil eintretendeIn addition to the filter element 20 provided according to the invention on the valve needle 18, the injection valve can have a fuel filter 55. The fuel filter 55 then protrudes into the flow bore 46 of the core 2 at its inlet side, the end 56 facing away from the spray orifice plate 34. The one entering the fuel injector
Brennstoff durchströmt den Brennstoffilter 55 in bekannter Weise und tritt in radialer Richtung aus dem Brennstoffilter 55 aus. Der Brennstoffilter 55 sorgt für die Herausfiltrie- rung solcher im Brennstoff mitgeführter Partikel, die auf- grund ihrer Größe oder chemischen Zusammensetzung im Ein¬ spritzventil Verstopfungen oder Beschädigungen verursachen könnten. Beispielsweise durch Einschieben in die gestufte Strδmungsbohrung 46 des Kerns 2 ist der Brennstoffilter 55 montierbar, wobei er im montierten Zustand zum Beispiel mit einem Haltering 58 mit einer leichten radialen Pressung an der Wandung der Strömungsbohrung 46 anliegt. Das Filterge¬ webe des Brennstoffilters 55 ist in einem aus Kunststoff gefertigten, becherförmigen Trägerteil 60 mit zum Beispiel drei Axialstegen 61 befestigt.Fuel flows through the fuel filter 55 in a known manner and exits the fuel filter 55 in the radial direction. The fuel filter 55 ensures that particles carried in the fuel are filtered out which, because of their size or chemical composition, could cause blockages or damage in the injection valve. For example, by pushing it into the stepped flow bore 46 of the core 2, the fuel filter 55 can be mounted, and in the assembled state it rests, for example, with a retaining ring 58 with a slight radial pressure on the wall of the flow bore 46. The filter fabric of the fuel filter 55 is fastened in a cup-shaped carrier part 60 made of plastic with, for example, three axial webs 61.
Neben dem Brennstoffilter 55 am zulaufseitigen Ende 56 des Kerns 2 oder statt dessen ist das Filterelement 20 an der erfindungsgemäß ausgebildeten Ventilnadel 18 vorgesehen. Im montierten Zustand des Einspritzventils ist das Filterele- ment 20 in beziehungsweise an der Ventilnadel 18 integriert. Fertigungstechnisch ist es allerdings sinnvoll, das Filter- element 20 getrennt von den einzelnen Komponenten der Ven¬ tilnadel 18 herzustellen. Das Aufschieben, Einsetzen oder andere Möglichkeiten des Anbringens des Filterelements 20 in beziehungsweise an der Ventilnadel 18 werden nachfolgend näher erläutert. Das in beziehungsweise an der Ventilnadel 18 angeordnete Filterelement 20 hat die Funktion, alle Par¬ tikel und Verunreinigungen stromaufwärts des Ventilsitzes 30 im Inneren des Einspritzventils vom Ventilsitz 30 fernzuhal¬ ten und damit Verstopfungen beziehungsweise Undichtheiten am Ventilsitz 30 zu vermeiden. Verunreinigungen im Inneren des Einspritzventils können zum Beispiel beim Einschieben der Einstellhülse 48, beim Einpressen des Brennstoffilters 55, durch Verschleiß der Anschlagflächen von Kern 2 und Anker 27 beziehungsweise durch fertigungsbedingte Grate an verschie- denen Bauteilen des Einspritzventils auftreten beziehungs¬ weise entstehen.In addition to the fuel filter 55 at the inlet end 56 of the core 2 or instead, the filter element 20 is provided on the valve needle 18 designed according to the invention. In the assembled state of the injection valve, the filter element 20 is integrated in or on the valve needle 18. From a manufacturing point of view, however, it makes sense to to produce element 20 separately from the individual components of valve needle 18. The pushing on, inserting or other options for attaching the filter element 20 in or on the valve needle 18 are explained in more detail below. The filter element 20 arranged in or on the valve needle 18 has the function of keeping all particles and contaminants upstream of the valve seat 30 in the interior of the injection valve away from the valve seat 30 and thus preventing blockages or leaks at the valve seat 30. Contamination in the interior of the injection valve can occur, for example, when inserting the adjusting sleeve 48, when the fuel filter 55 is pressed in, due to wear on the abutment surfaces of the core 2 and armature 27 or as a result of production-related burrs on various components of the injection valve.
In der Figur 1 ist eine sehr einfache Kombination des Fil¬ terelements 20 mit der Ventilnadel 18 dargestellt. Das Fil- terelement 20 zum Beispiel aus einem üblichen Polyamidgewebe als Siebgewebe 62 ist in der Form eines Siebstrumpfes ohne eine Kunststoffverstärkung über den Ventilnadelabschnitt 19 gezogen und umgibt diesen radial über die gesamte axiale Erstreckungslänge vollständig. Der Siebstrumpf ist bei- spielsweise mit einer axial verlaufenden Naht 63 auf dem1 shows a very simple combination of the filter element 20 with the valve needle 18. The filter element 20, for example made of a conventional polyamide fabric as a screen fabric 62, is drawn in the form of a screen stocking without a plastic reinforcement over the valve needle section 19 and completely surrounds it radially over the entire axial extension length. The sieve stocking is, for example, with an axially running seam 63 on the
Ventilnadelabschnitt 19 verschweißt und sitzt somit straff auf dem Ventilnadelabschnitt 19. Die Figuren 2 bis 11 zeigen verschiedene Ausführungsbeispiele von in beziehungsweise an der Ventilnadel 18 integrierten Filterelementen 20. Auf die Darstellung des gesamten Einspritzventils wird in diesen Figuren verzichtet, da das in der Figur 1 dargestellte Brennstoffeinspritzventil nur beispielhaft für Einsatzmög¬ lichkeiten von Filterelementen 20 stehen soll und also ande¬ re Baureihen von Ventilen, speziell von Einspritzventilen auch mit den erfindungsgemäßen Ventilnadeln 18 bestückbar sind. Die gegenüber dem in der Figur 1 dargestellten Ausfüh- rungsbeispiel der Ventilnadel 18 gleichbleibenden bezie¬ hungsweise gleichwirkenden Teile sind auch in den Figuren 2 bis 11 durch die gleichen Bezugszeichen gekennzeichnet.Valve needle section 19 is welded and thus sits tightly on valve needle section 19. FIGS. 2 to 11 show different exemplary embodiments of filter elements 20 integrated in or on valve needle 18. The representation of the entire injection valve is omitted in these figures, since this is shown in FIG. 1 Fuel injection valve is intended only as an example for possible uses of filter elements 20 and therefore other series of valves, especially injection valves, can also be equipped with the valve needles 18 according to the invention. Compared to the embodiment shown in FIG. Example of the same or equivalent parts of the valve needle 18 are also identified in FIGS. 2 to 11 by the same reference numerals.
Eine Ventilnadel 18 mit dem als Siebstrumpf ausgebildetenA valve needle 18 with the sieve stocking
Filterelement 20 gemäß dem in der Figur 1 dargestellten Aus¬ führungsbeispiel ist nochmals in der Figur 2 gezeigt. Ohne eine Kunststoffverstärkung in der Form eines Trägerkörpers ist das Filterelement 20 über den Ventilnadelabschnitt 19 gezogen und umgibt diesen vollständig radial. Neben der bereits genannten Verschweißung (Naht 63) ist ein Verrut¬ schen des Filterelements 20 auch dadurch ausgeschlossen, daß der Anker 27 als mit dem Ventilnadelabschnitt 19 zum Bei¬ spiel durch Schweißen fest verbundenes Teil auch das Siebge- webe 62 umgreift und zwischen sich und dem Ventilnadelab¬ schnitt 19 einspannt.Filter element 20 according to the exemplary embodiment shown in FIG. 1 is shown again in FIG. 2. Without a plastic reinforcement in the form of a carrier body, the filter element 20 is pulled over the valve needle section 19 and surrounds it completely radially. In addition to the welding (seam 63) already mentioned, slipping of the filter element 20 is also ruled out in that the armature 27, as a part firmly connected to the valve needle section 19, for example by welding, also engages around the screen fabric 62 and between it and the valve needle section 19 clamps.
Ein zweites Ausführungsbeispiel einer Ventilnadel 18 mit am äußeren Umfang des Ventilnadelabschnitts 19 angebrachtem Filterelement 20 zeigen die Figuren 3 und 4. Das hülsenför- mige Filterelement 20, das in der Figur 3 im Schnitt darge¬ stellt ist, ist nun ähnlich dem Brennstoffilter 55 ausgebil¬ det, also bestehend aus einem zum Beispiel aus Kunststoff gefertigten Trägerkörper 64 und dem eigentlichen Siebgewebe 62, zum Beispiel einem Polyamidgewebe. Das Siebgewebe 62 wird beispielsweise bei der Herstellung des Trägerkorpers 64 mitangespritzt. Der Trägerkδrper 64 wird von einem umlaufen¬ den Ringabschnitt 67, der sich dem Ventilschiießkδrper 24 abgewandt erstreckt, und von beispielsweise drei in Axial- richtung verlaufenden und um 120° am Umfang des Filterele¬ ments 20 versetzt liegenden Axialstegen 65, die das Siebge¬ webe 62 minimal überdecken, gebildet. Die Axialstege 65 erstrecken sich also ausgehend von dem Ringabschnitt 67 bis unmittelbar zum Ventilschließkörper 24. Die Figur 4 als Schnittdarstellung eines Schnittes entlang der Linie IV-IV in Figur 3 verdeutlicht nochmals die Anordnung der Axialste- ge 65, die nur eine geringe Breite aufweisen und somit die Brennstoffaustrittsöffnungen im Ventilnadelabschnitt 19 auch in ungünstiger Stellung nur in geringem Maße abdecken. Der Ringabschnitt 67 ist so ausgebildet, daß er einen am strom- abwärtigen Ende des Ankers 27 existierenden Bund 70 über¬ greifen kann und somit eine Verrastung zwischen Trägerkörper 64 und Anker 27 vorliegt, wodurch ein Verrutschen des Fil¬ terelements 20 ausgeschlossen ist. Das Filterelement 20 liegt also bei diesem Ausführungsbeispiel vollständig außer- halb der eigentlichen Ventilnadel 18 vor.FIGS. 3 and 4 show a second exemplary embodiment of a valve needle 18 with a filter element 20 attached to the outer circumference of the valve needle section 19. The sleeve-shaped filter element 20, which is shown in section in FIG. 3, is now similar to the fuel filter 55 det, ie consisting of a carrier body 64 made, for example, of plastic and the actual screen fabric 62, for example a polyamide fabric. The screen fabric 62 is also molded, for example, during the manufacture of the carrier body 64. The carrier body 64 is surrounded by a circumferential ring section 67, which extends away from the valve closing body 24, and by, for example, three axial webs 65 which run in the axial direction and are offset by 120 ° on the circumference of the filter element 20 and which serve as the sieve fabric 62 minimal cover, formed. The axial webs 65 thus extend from the ring section 67 to directly to the valve closing body 24. FIG. 4 as a sectional illustration of a section along the line IV-IV in FIG. 3 again illustrates the arrangement of the axial webs. ge 65, which have only a small width and thus only cover the fuel outlet openings in the valve needle section 19 to a small extent even in an unfavorable position. The ring section 67 is designed such that it can overlap a collar 70 existing at the downstream end of the armature 27 and thus there is a latching between the carrier body 64 and the armature 27, which prevents the filter element 20 from slipping. In this exemplary embodiment, the filter element 20 is therefore completely outside of the actual valve needle 18.
Im Gegensatz dazu wird das Filterelement 20 im folgenden Ausführungsbeispiel, das in den Figuren 5 und 6 dargestellt ist, in den rohrförmigen Ventilnadelabschnitt 19 eingescho- ben. Das Filterelement 20 besitzt dabei eine weitgehend ähn¬ liche Gestalt wie das in den Figuren 3 und 4 gezeigte Fil¬ terelement 20. Es besteht also ebenfalls aus einem aus Kunststoff gefertigten Trägerkörper 64 und dem Siebgewebe 62. Um eine ausreichende Stabilität des Filterelements 20 zu erhalten, weist der Trägerkδrper 64 einen dem Ventilschlie߬ körper 24 zugewandten Boden 72, einen umlaufenden, dem Ven- tilschließkδrper 24 abgewandten Ringabschnitt 67 und zwei oder drei zwischen Ringabschnitt 67 und Boden 72 axial ver¬ laufende und um 180° beziehungsweise um 120° am Umfang des Filterelements 20 versetzt liegende Axialstege 65 auf. DasIn contrast to this, in the following exemplary embodiment, which is shown in FIGS. 5 and 6, the filter element 20 is pushed into the tubular valve needle section 19. The filter element 20 has a largely similar shape to the filter element 20 shown in FIGS. 3 and 4. It therefore also consists of a carrier body 64 made of plastic and the sieve fabric 62. In order to maintain sufficient stability of the filter element 20 , the carrier body 64 has a bottom 72 facing the valve closing body 24, a circumferential ring section 67 facing away from the valve closing body 24 and two or three axially extending between the ring section 67 and the bottom 72 and 180 ° or 120 ° on the circumference of the filter element 20 offset axial webs 65. The
Siebgewebe 62 wird zum Beispiel wiederum bei der Herstellung des Trägerkörpers 64 mitangespritzt. Während der Boden 72 den inneren Durchmesser des Ventilnadelabschnitts 19 zwi¬ schen den Brennstoffaustrittsδffnungen und dem Ventil- schließkörper 24 vollständig schließt und somit zur Ablage¬ rung der Partikel und Verunreinigungen dienen kann, stellt der Ringabschnitt 67 einen offenen Querschnitt dar, so daß der Brennstoff ungehindert in den Ventilnadelabschnitt 19 einströmen kann. Das Filterelement 20 ist also becherförmig ausgebildet. Der Ringabschnitt 67 besitzt beispielsweise einen solchen äußeren Durchmesser, daß eine Preßpassung im Ventilnadelabschnitt 19 vorliegt, so daß eine sehr einfache Befestigungsart garantiert ist, wobei zum Einschieben des Filterelements 20 die Kraft eines menschlichen Fingers völ¬ lig ausreichend ist. Die Figur 6, die einen Schnitt entlang der Linie VI-VI in Figur 5 zeigt, verdeutlicht die Anordnung der beispielsweise drei Axialstege im Inneren des Ventilna¬ delabschnitts 19.Screen fabric 62 is, for example, also molded on during the manufacture of the carrier body 64. While the bottom 72 completely closes the inner diameter of the valve needle section 19 between the fuel outlet openings and the valve closing body 24 and can thus serve to deposit the particles and impurities, the ring section 67 represents an open cross section so that the fuel is unhindered can flow into the valve needle section 19. The filter element 20 is thus cup-shaped. The ring portion 67 has, for example, such an outer diameter that an interference fit in Valve needle section 19 is present, so that a very simple type of fastening is guaranteed, the force of a human finger being completely sufficient to insert the filter element 20. FIG. 6, which shows a section along the line VI-VI in FIG. 5, illustrates the arrangement of the, for example, three axial webs in the interior of the valve needle section 19.
In der Figur 8 ist ein Betätigungsteil bestehend aus dem Ventilnadelabschnitt 19 und dem Anker 27, das einteilig nach dem sogenannten Metal-Injection-Molding-Verfahren (MIM) her¬ gestellt ist, im Schnitt dargestellt. Das unter anderem aus der DE-PS 42 30 376 bereits bekannte Verfahren umfaßt die Herstellung von Formteilen aus einem Metallpulver mit einem Bindemittel, zum Beispiel einem Kunststoffbindemittel, bei¬ spielsweise auf konventionellen Kunststoffspritzgießmaschi- nen und das nachfolgende Entfernen des Bindemittels und Sin¬ tern des verbleibenden Metallpulvergerüsts. Der Ventil- schließkδrper 24 wird anschließend beispielsweise mittels einer Schweißverbindung am stromabwärtigen Ende des Betäti¬ gungsteils mit dem Ventilnadelabschnitt 19 fest und dicht verbunden. Eine Ventilnadel 18, bei der wenigstens das Betä¬ tigungsteil aus Ventilabschnitt 19 und Anker 27 einteilig als MIM-Teil ausgebildet ist und der Ventilnadelabschnitt 19 ein massives Teil darstellt, wurde bereits in der deutschen Patentanmeldung DE-P 44 15 850.5 vorgeschlagen.In FIG. 8, an actuating part consisting of the valve needle section 19 and the armature 27, which is produced in one piece by the so-called metal injection molding method (MIM), is shown in section. The method already known, inter alia, from DE-PS 42 30 376 comprises the production of molded parts from a metal powder with a binder, for example a plastic binder, for example on conventional plastic injection molding machines and the subsequent removal of the binder and sintering remaining metal powder structure. The valve closing body 24 is then firmly and tightly connected to the valve needle section 19, for example by means of a welded connection at the downstream end of the actuating part. A valve needle 18, in which at least the actuating part consisting of valve section 19 and armature 27 is formed in one piece as a MIM part and valve needle section 19 represents a solid part, has already been proposed in German patent application DE-P 44 15 850.5.
Die Figur 7 zeigt eine Draufsicht auf die Ventilnadel 18 beziehungsweise den Anker 27 von einer stromaufwartigen, dem Kern 2 zugewandten Stirnseite 74 aus. In dieser Draufsicht ist gut zu erkennen, daß ein axial gegenüber der Stirnseite 74 tiefer liegender und einen geringeren Durchmesser als die Stirnseite 74 aufweisender Halteabsatz 75 zum Abstützen der Rückstellfeder 26 durch beispielsweise drei oder vier axial, also in Richtung der Ventillängsachse 10 verlaufende Axial¬ nuten 76 unterbrochen ist. Die Axialnuten 76 erstrecken sich über die gesamte verbleibende Länge des Ankers 27 und dienen dazu, den aus der Strömungsbohrung 46 des Kerns 2 kommenden Brennstoff ungehindert in Richtung zum Ventilsitz 30 strömen zu lassen.FIG. 7 shows a plan view of the valve needle 18 or the armature 27 from an upstream end face 74 facing the core 2. In this plan view it can be clearly seen that a holding shoulder 75, which is axially lower than the end face 74 and has a smaller diameter than the end face 74, for supporting the return spring 26 by, for example, three or four axial grooves running in the direction of the valve longitudinal axis 10 76 is interrupted. The axial grooves 76 extend over the entire remaining length of the armature 27 and serve to allow the fuel coming from the flow bore 46 of the core 2 to flow unhindered in the direction of the valve seat 30.
Die Figur 8 ist eine Darstellung eines Schnittes entlang der Linie VIII-VIII in Figur 7, wobei der Schnitt so geführt ist, daß er sowohl durch das massive Material vom Halteab¬ satz 30 ausgehend in axialer Richtung des Ankers 27 verläuft als auch durch eine Axialnut 76 im Anker 27. Der Ventilna¬ delabschnitt 19 ragt teilweise in den Anker 27 hinein, das heißt, eine stromaufwärtige, dem Halteabsatz 30 zugewandte Stirnfläche 77 des Ventilnadelabschnitts 19 liegt weiter stromaufwärts als ein sich an der äußeren Kontur des Betäti- gungsteils ergebender Absatz 78 von Anker 27 zu Ventilnadel¬ abschnitt 19, an dem die Axialnuten 76 enden. Die Axialnuten 76 stellen jedoch in ihrem unteren Abschnitt, nämlich genau ab der Stirnfläche 77 des Ventilnadelabschnitts 19 keine Nu¬ ten mehr dar, sondern durch die vollständige Materialum- Schließung sich fluchtend anschließende, axiale Strömungska¬ näle 80. Der Brennstoff tritt im Bereich des Absatzes 78 aus den Strömungskanälen 80 zumindest teilweise als Wandfilm des Ventilnadelabschnitts 19 aus, da die innere Begrenzung jedes Strömungskanals 80 durch den Ventilnadelabschnitt 19 gegeben ist. Unmittelbar stromabwärts des Absatzes 78 kann derFIG. 8 is an illustration of a section along the line VIII-VIII in FIG. 7, the section being carried out in such a way that it runs both through the solid material from the holding shoulder 30 in the axial direction of the armature 27 and through an axial groove 76 in the armature 27. The valve needle section 19 projects partially into the armature 27, that is to say that an upstream end face 77 of the valve needle section 19 facing the holding shoulder 30 lies further upstream than a shoulder 78 resulting on the outer contour of the actuating part from armature 27 to valve needle section 19, at which the axial grooves 76 end. However, in its lower section, namely exactly from the end face 77 of the valve needle section 19, the axial grooves 76 no longer represent grooves, but instead, due to the complete encapsulation of the material, axial flow channels 80 adjoining one another in alignment. The fuel occurs in the area of the shoulder 78 from the flow channels 80 at least partially as a wall film of the valve needle section 19, since the inner boundary of each flow channel 80 is given by the valve needle section 19. Immediately downstream of paragraph 78, the
Brennstoff in ein den Ventilnadelabschnitt 19 umgebendes Filterelement 20 eintreten.Fuel enter a filter element 20 surrounding the valve needle section 19.
Das hülsenförmige Filterelement 20 wird beispielsweise ähn- lieh dem in den Figuren 3 und 4 dargestellten Ausführungs¬ beispiel durch eine Verrastung an dem Ventilnadelabschnitt 19 befestigt. Der Ventilnadelabschnitt 19 als ein Abschnitt des mittels MIM-Verfahren hergestellten Betätigungsteils weist dazu an seinem Umfang axial nahe des Absatzes 78 zum Beispiel vier Rastnasen 82 auf, die jeweils um 90° versetzt am Ventilnadelabschnitt 19 ausgebildet sind. Diese Rastnasen 82 kann nun ein aus Kunststoff gefertigter Trägerkörper 64 des Filterelements 20 umgreifen, womit eine sichere Fixie¬ rung des Filterelements 20 an der Ventilnadel 18 garantiert ist. In Umfangsrichtung zwischen den Rastnasen 82 verbleiben Strömungsräume 83 für den über die Strδmungskanäle 80 zu¬ strömenden Brennstoff, da der Trägerkörper 64 mit seinem oberen Ringabschnitt 85 einen größeren Innendurchmesser besitzt als der Durchmesser des Ventilnadelabschnitts 19 zwischen den Rastnasen 82. Um eine ausreichende Stabilität zu gewährleisten, gehört neben dem oberen Ringabschnitt 85 auch ein unterer Ringabschnitt 86 zum Trägerkörper 64, der den stromabwärtigen Abschluß des Filterelements 20 bildet. Das Siebgewebe 62, über das zwischen den beiden Ringab¬ schnitten 85 und 86 der Brennstoff radial nach außen strömt, ist beispielsweise ebenfalls bei der Herstellung des Träger¬ körpers 64 mitangespritzt worden. Die beiden Ringabschnitte 85 und 86 können durch Axialstege miteinander verbunden sein oder auch getrennt voneinander vorliegen, wenn nur das Sieb¬ gewebe 62 zwischen beiden Ringabschnitten 85 und 86 vorhan- den sein soll.The sleeve-shaped filter element 20 is fastened to the valve needle section 19, for example, in a manner similar to the embodiment shown in FIGS. 3 and 4. For this purpose, the valve needle section 19 as a section of the actuating part produced by means of the MIM method has, for example, four latching lugs 82 on its circumference axially close to the shoulder 78, which are each offset on the valve needle section 19 by 90 °. These latches 82 can now encompass a carrier body 64 made of plastic of the filter element 20, with which a secure fixation of the filter element 20 on the valve needle 18 is guaranteed. Flow spaces 83 remain in the circumferential direction between the locking lugs 82 for the fuel flowing in via the flow channels 80, since the carrier body 64 with its upper ring section 85 has a larger inner diameter than the diameter of the valve needle section 19 between the locking lugs 82. In order to ensure sufficient stability , in addition to the upper ring section 85, a lower ring section 86 also belongs to the carrier body 64, which forms the downstream end of the filter element 20. The screen fabric 62, through which the fuel flows radially outward between the two ring sections 85 and 86, has also been molded on, for example, during the manufacture of the carrier body 64. The two ring sections 85 and 86 can be connected to one another by axial webs or can also be separate from one another if only the screen fabric 62 is to be present between the two ring sections 85 and 86.
Die Figuren 9 und 10 sind Darstellungen von Schnitten ent¬ lang der Linien IX-IX beziehungsweise X-X in Figur 8 durch den oberen Ringabschnitt 85 des Trägerkörpers 64 des Filter- elements 20. Besonders deutlich wird nun die Ausbildung der Rastnasen 82, die sich um jeweils 90° versetzt vom Umfang des Ventilnadelabschnitts 19 radial nach außen erstrecken und somit die Möglichkeit der Verrastung des Trägerkörpers 64 bieten. Die innere Öffnung des Ringabschnitts 85 des Trä- gerkörpers 64 ist nicht kreisförmig ausgeführt, sondern mit verschiedenen Bereichen größerer und kleinerer Öffnungs- weite. Zur Aufnahme der vier Rastnasen 82 sind beispielswei¬ se im Ringabschnitt 85 auch vier Ausnehmungen 88 vorgesehen, in die die Rastnasen 82 eingreifen. Die zwischen jeweils zwei Rastnasen 82 gebildeten Strömungsräume 83 besitzen ihre größte Weite genau in der Mitte zwischen zwei Rastnasen 82, da der Ventilnadelabschnitt 19 einen kreisförmigen Quer¬ schnitt und die innere Öffnung des Ringabschnitts 85 einen weitgehend quadratischen Querschnitt hat. Ein zentral in einem Quadrat angeordneter Kreis hat den größten Abstand immer zu den Eckpunkten des Quadrates, die hier also genau mittig zwischen zwei Rastnasen 82 liegen. Der Brennstoff ge¬ langt von den Axialnuten 76 kommend über die Strömungskanäle 80 im Anker 27 direkt in die Strömungsräume 83 und tritt dann radial durch das Siebgewebe 62 aus dem Filterelement 20 in Richtung zum Ventilsitz 30 aus. Im Brennstoff mitgeführte Partikel können sich in einer Keilöffnung 89 des leicht keilförmig zu der Ventilnadel 18 hin ausgeführten unteren Ringabschnittε 86 ablagern.FIGS. 9 and 10 are representations of sections along lines IX-IX and XX in FIG. 8 through the upper ring section 85 of the carrier body 64 of the filter element 20. The formation of the latching lugs 82, which are in each case, becomes particularly clear Extend radially outwards from the circumference of the valve needle section 19 by 90 ° and thus offer the possibility of locking the carrier body 64. The inner opening of the ring section 85 of the carrier body 64 is not circular, but with different areas of larger and smaller opening width. To accommodate the four locking lugs 82, four recesses 88 are provided in the ring section 85, for example, into which the locking lugs 82 engage. The flow spaces 83 formed between two locking lugs 82 have their greatest width exactly in the middle between two locking lugs 82, since the valve needle section 19 has a circular cross section and the inner opening of the ring section 85 has a largely square cross section. A circle arranged centrally in a square always has the greatest distance from the corner points of the square, which are therefore exactly in the middle between two locking lugs 82. The fuel comes from the axial grooves 76 via the flow channels 80 in the armature 27 directly into the flow spaces 83 and then exits the filter element 20 radially through the screen fabric 62 in the direction of the valve seat 30. Particles entrained in the fuel can be deposited in a wedge opening 89 of the lower ring section 86, which is slightly wedge-shaped toward the valve needle 18.
Bei einer sehr kurzen Ventilnadel 18, die bereits in der deutschen Patentanmeldung DE-P 43 10 819.9 vorgeschlagen wurde und in der Figur 11 dargestellt ist, bietet es sich an, ein tellerfederfδrmiges Filterelement 20 einzusetzen. Das Betätigungsteil aus Anker 27 und Ventilnadelabschnitt 19 • ist beispielsweise einteilig ausgebildet und besitzt wenig¬ stens einen im Anker 27 verlaufenden Strömungskanal 80, der an dem sich an der äußeren Kontur des Betätigungsteils erge¬ benden Absatz 78 von Anker 27 zu Ventilnadelabschnitt 19 endet, womit der Brennstoff unmittelbar zum Ventilsitz 30 gelangen kann. Das Filterelement 20 befindet sich deshalb zwischen dem Ende des Strömungskanals 80 am Absatz 78 und dem Ventilsitz 30. Bei dem sehr kleinen Bauraum, der sich durch die kurze Ventilnadel 18 ergibt, ist es nur möglich, ein Filterelement 20 mit geringen Abmessungen zu verwenden. Das Filterelement 20 weist darum nur zwei, einen sehr klei¬ nen Querschnitt besitzende, umlaufende, aus Kunststoff oder Metall gefertigte Halteringe 90, 91 auf, die einen unter¬ schiedlichen Durchmesser besitzen und das Siebgewebe 62 zwi¬ schen sich einspannen. Das Siebgewebe 62 verläuft εtromab- wärts sich kegelstumpfförmig verjüngend, da der dem Ventil- εchließkörper 24 zugewandte Haltering 91 einen kleineren Durchmesser hat als der dem Ventilschließkörper 24 abgewan¬ dte Haltering 90. Die Halteringe 90 und 91 des Filterele¬ ments 20 finden Aufnahme in dafür am Absatz 78 des Ankers 27 und an dem Ventilnadelabschnitt 19 vorgesehenen Ringaufnah- menuten 92. Durch Einclipsen beziehungsweise Einpresεen der Halteringe 90 in die Ringaufnahmenuten 92 (Preßpaεεung) ist ein ausreichend sicherer Sitz garantiert.In the case of a very short valve needle 18, which was already proposed in German patent application DE-P 43 10 819.9 and is shown in FIG. 11, it is advisable to use a filter element 20 in the form of a plate spring. The actuating part consisting of armature 27 and valve needle section 19 is, for example, formed in one piece and has at least one flow channel 80 running in armature 27, which ends at armature 27 from armature 27 to valve needle section 19, resulting on the outer contour of the actuating part, with which the fuel can reach valve seat 30 directly. The filter element 20 is therefore located between the end of the flow channel 80 at the shoulder 78 and the valve seat 30. With the very small space that results from the short valve needle 18, it is only possible to use a filter element 20 with small dimensions. The filter element 20 therefore has only two circumferential retaining rings 90, 91, which have a very small cross-section and are made of plastic or metal, which have a different diameter and clamp the screen fabric 62 between them. The sieve fabric 62 tapers downstream in the shape of a truncated cone, since the retaining ring 91 facing the valve closing body 24 has a smaller one The diameter is that of the retaining ring 90 facing away from the valve closing body 24. The retaining rings 90 and 91 of the filter element 20 are accommodated in ring receiving grooves 92 provided for this purpose on the shoulder 78 of the armature 27 and on the valve needle section 19. By clipping or pressing in the retaining rings 90 in the ring receiving grooves 92 (press fit) a sufficiently secure fit is guaranteed.
Die beschriebenen und auch weitere ähnliche Formen von Fil- terelementen 20 können an den verschiedensten Ventilnadeln 18 von Ventilen, speziell von Einεpritzventilen, auch an hier nicht näher erläuterten Ventilnadeln, zum Einsatz kom¬ men. The described and also other similar forms of filter elements 20 can be used on a wide variety of valve needles 18 of valves, especially of injection valves, also on valve needles which are not explained in more detail here.

Claims

Patentansprüche claims
1. Ventilnadel, insbeεondere für elektromagnetisch betätig- bare Brennstoffeinspritzventile für Brennstoffeinspritzanla¬ gen von Brennkraftmaschinen, mit einem Ventilnadelabschnitt und einem Ventilschließkörper, dadurch gekennzeichnet, daß die Ventilnadel (18) ein Filterelement (20) aufweist.1. Valve needle, in particular for electromagnetically actuated fuel injection valves for fuel injection systems of internal combustion engines, with a valve needle section and a valve closing body, characterized in that the valve needle (18) has a filter element (20).
2. Ventilnadel nach Anspruch 1, dadurch gekennzeichnet, daß das Filterelement (20) in der Form eines Siebstrumpfeε nur aus einem Siebgewebe (62) besteht.2. Valve needle according to claim 1, characterized in that the filter element (20) in the form of a Siebstrumpfeε consists only of a screen fabric (62).
3. Ventilnadel nach Anspruch 1, dadurch gekennzeichnet, daß das Filterelement (20) von einem Trägerkδrper (64) und einem3. Valve needle according to claim 1, characterized in that the filter element (20) by a Trägerkδrper (64) and one
Siebgewebe (62) gebildet wird.Screen fabric (62) is formed.
4. Ventilnadel nach Anspruch 2 oder 3, dadurch gekennzeich¬ net, daß das Siebgewebe (62) des Filterelements (20) ein Polyamidgewebe ist.4. Valve needle according to claim 2 or 3, characterized gekennzeich¬ net that the screen fabric (62) of the filter element (20) is a polyamide fabric.
5. Ventilnadel nach Anspruch 1, dadurch gekennzeichnet, daß das Filterelement (20) den Ventilnadelabschnitt (19) der Ventilnadel (18) äußerlich umgibt.5. Valve needle according to claim 1, characterized in that the filter element (20) surrounds the valve needle portion (19) of the valve needle (18) externally.
6. Ventilnadel nach Anspruch 1, dadurch gekennzeichnet, daß daε Filterelement (20) im Inneren des rohrförmig ausgebilde¬ ten Ventilnadelabεchnittε (19) der Ventilnadel (18) angeord¬ net ist. - 16 -6. Valve needle according to claim 1, characterized in that daε filter element (20) in the interior of the tube-shaped valve valve section (19) of the valve needle (18) is angeord¬ net. - 16 -
7. Ventilnadel nach Anεpruch 1, dadurch gekennzeichnet, daß daε Filterelement (20) durch eine Rastverbindung (67, 70; 82, 85) an der Ventilnadel (18) fixiert ist.7. Valve needle according to claim 1, characterized in that the filter element (20) is fixed to the valve needle (18) by a latching connection (67, 70; 82, 85).
8. Ventilnadel nach Anspruch 1, dadurch gekennzeichnet, daß das Filterelement (20) eine hülsenförmige, becherförmige oder kegelstumpfförmige Gestalt besitzt.8. Valve needle according to claim 1, characterized in that the filter element (20) has a sleeve-shaped, cup-shaped or frustoconical shape.
9. Ventilnadel nach Anspruch 1, dadurch gekennzeichnet, daß der Ventilnadelabεchnitt (19) an εeiner dem Ventilschlie߬ körper (24) abgewandten Seite mit einem Anker (27) verbunden ist und sich daε Siebgewebe (62) wenigstens axial zwiεchen dem Ventilschließkδrper (24) und dem Anker (27) erstreckt.9. Valve needle according to claim 1, characterized in that the valve needle section (19) is connected to an armature (27) on its side facing away from the valve closing body (24) and the sieve fabric (62) is at least axially between the valve closing body (24). and extends the anchor (27).
10. Ventilnadel nach Anspruch 1, dadurch gekennzeichnet, daß der Ventilnadelabschnitt (19) an seiner dem Ventilschlie߬ körper (24) abgewandten Seite mit einem Anker (27) verbunden ist und daε Filterelement (20) durch eine Verrastung (67, 70) an dem Anker (27) befestigt ist. 10. Valve needle according to claim 1, characterized in that the valve needle section (19) on its the valve closing body (24) facing away from an armature (27) is connected and daε filter element (20) by a latch (67, 70) the anchor (27) is attached.
PCT/DE1995/000742 1994-06-23 1995-06-07 Valve needle with filter element WO1996000348A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19944421881 DE4421881A1 (en) 1994-06-23 1994-06-23 Valve needle
DEP4421881.8 1994-06-23

Publications (1)

Publication Number Publication Date
WO1996000348A1 true WO1996000348A1 (en) 1996-01-04

Family

ID=6521258

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE1995/000742 WO1996000348A1 (en) 1994-06-23 1995-06-07 Valve needle with filter element

Country Status (2)

Country Link
DE (1) DE4421881A1 (en)
WO (1) WO1996000348A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LT4905B (en) 1998-11-03 2002-04-25 Novabrick International Inc Manually breakable block
US6645717B1 (en) 1999-03-11 2003-11-11 Whatman, Inc. Solid medium and process for the storage and rapid purification of nucleic acid
US6958392B2 (en) 1998-10-09 2005-10-25 Whatman, Inc. Methods for the isolation of nucleic acids and for quantitative DNA extraction and detection for leukocyte evaluation in blood products
US7638099B2 (en) 2004-04-09 2009-12-29 Vivebio, Llc Devices and methods for collection, storage and transportation of biological specimens
WO2011095370A1 (en) * 2010-02-04 2011-08-11 Delphi Technologies Holding S.À.R.L. Needle for needle valve
CN107847830A (en) * 2015-07-16 2018-03-27 卡特彼勒公司 Filter adaptor for fuel injector
WO2019101473A1 (en) * 2017-11-23 2019-05-31 Pierburg Gmbh Sleeve for a fluid valve and fluid valve through which fluid can flow axially

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19603383A1 (en) * 1996-01-31 1997-08-07 Teves Gmbh Alfred Solenoid valve
DE19631280A1 (en) * 1996-08-02 1998-02-05 Bosch Gmbh Robert Fuel injector and manufacturing method
US5967424A (en) * 1998-06-24 1999-10-19 General Motors Corporation Fuel injector filter
DE10130205A1 (en) * 2001-06-22 2003-01-02 Bosch Gmbh Robert Fuel injector
DE102005052256B4 (en) * 2004-11-04 2016-02-04 Robert Bosch Gmbh Injector
DE102004053762B4 (en) * 2004-11-08 2013-10-10 Robert Bosch Gmbh Valve needle for fluid valve
EP1724464B1 (en) * 2005-05-09 2008-07-16 Siemens Aktiengesellschaft Injector and valve group for the injector
DE102005037552B4 (en) 2005-08-09 2018-10-31 Robert Bosch Gmbh Fuel injector
DE102006027614B4 (en) * 2006-06-13 2009-02-05 L'orange Gmbh Injection injector for internal combustion engines
DE102008040843B4 (en) 2008-07-29 2016-10-06 Robert Bosch Gmbh Valve
DE102012201940A1 (en) * 2012-02-09 2013-08-14 Robert Bosch Gmbh Valve for metering a flowing medium
DE102013201897A1 (en) * 2013-02-06 2014-08-07 Robert Bosch Gmbh Valve for metering fluid

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3841489A (en) * 1973-05-02 1974-10-15 Kuss R And Co Inc Fluid filter
US4372491A (en) * 1979-02-26 1983-02-08 Fishgal Semyon I Fuel-feed system
JPS61283760A (en) * 1985-06-07 1986-12-13 Hitachi Ltd Fuel injection valve
US4700891A (en) * 1985-10-02 1987-10-20 Robert Bosch Gmbh Electromagnetically actuatable fuel injection valve
GB2220984A (en) * 1988-07-20 1990-01-24 Lucas Ind Plc Fuel injection nozzle
EP0399640A1 (en) * 1989-05-22 1990-11-28 General Motors Corporation Fuel injection nozzle
JPH0510221A (en) * 1991-07-03 1993-01-19 Nippondenso Co Ltd Solenoid fuel injection valve
US5186882A (en) * 1990-11-29 1993-02-16 Robert Bosch Gmbh Method for mounting a filter on the valve
DE4140070A1 (en) * 1991-12-05 1993-06-09 Mercedes-Benz Aktiengesellschaft, 7000 Stuttgart, De Fuel injection valve esp. for mixture-compressing IC engine - has collection devices for dirt particles in fuel flow path upstream of valve seat
US5238192A (en) * 1991-12-18 1993-08-24 Siemens Automotive L.P. Filter for solenoid operated fluid metering devices
US5335863A (en) * 1993-05-03 1994-08-09 Siemens Automotive L.P. Filter cartridge mounting for a top-feed fuel injector

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3841489A (en) * 1973-05-02 1974-10-15 Kuss R And Co Inc Fluid filter
US4372491A (en) * 1979-02-26 1983-02-08 Fishgal Semyon I Fuel-feed system
JPS61283760A (en) * 1985-06-07 1986-12-13 Hitachi Ltd Fuel injection valve
US4700891A (en) * 1985-10-02 1987-10-20 Robert Bosch Gmbh Electromagnetically actuatable fuel injection valve
GB2220984A (en) * 1988-07-20 1990-01-24 Lucas Ind Plc Fuel injection nozzle
EP0399640A1 (en) * 1989-05-22 1990-11-28 General Motors Corporation Fuel injection nozzle
US5186882A (en) * 1990-11-29 1993-02-16 Robert Bosch Gmbh Method for mounting a filter on the valve
JPH0510221A (en) * 1991-07-03 1993-01-19 Nippondenso Co Ltd Solenoid fuel injection valve
DE4140070A1 (en) * 1991-12-05 1993-06-09 Mercedes-Benz Aktiengesellschaft, 7000 Stuttgart, De Fuel injection valve esp. for mixture-compressing IC engine - has collection devices for dirt particles in fuel flow path upstream of valve seat
US5238192A (en) * 1991-12-18 1993-08-24 Siemens Automotive L.P. Filter for solenoid operated fluid metering devices
US5335863A (en) * 1993-05-03 1994-08-09 Siemens Automotive L.P. Filter cartridge mounting for a top-feed fuel injector

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 011, no. 149 (M - 588) *
PATENT ABSTRACTS OF JAPAN vol. 17, no. 282 (M - 1420) *

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6958392B2 (en) 1998-10-09 2005-10-25 Whatman, Inc. Methods for the isolation of nucleic acids and for quantitative DNA extraction and detection for leukocyte evaluation in blood products
LT4905B (en) 1998-11-03 2002-04-25 Novabrick International Inc Manually breakable block
US6645717B1 (en) 1999-03-11 2003-11-11 Whatman, Inc. Solid medium and process for the storage and rapid purification of nucleic acid
US7638099B2 (en) 2004-04-09 2009-12-29 Vivebio, Llc Devices and methods for collection, storage and transportation of biological specimens
US8685748B2 (en) 2004-04-09 2014-04-01 Vivebio, Llc Devices and methods for collection, storage and transportation of biological specimens
US9359649B2 (en) 2004-04-09 2016-06-07 Vivebio, Llc Methods for collection, storage and transportation of biological specimens
WO2011095370A1 (en) * 2010-02-04 2011-08-11 Delphi Technologies Holding S.À.R.L. Needle for needle valve
US9297343B2 (en) 2010-02-04 2016-03-29 Delphi International Operations Luxembourg S.A.R.L. Needle for needle valve
CN107847830A (en) * 2015-07-16 2018-03-27 卡特彼勒公司 Filter adaptor for fuel injector
CN107847830B (en) * 2015-07-16 2020-04-03 卡特彼勒公司 Filter adapter for fuel injector
WO2019101473A1 (en) * 2017-11-23 2019-05-31 Pierburg Gmbh Sleeve for a fluid valve and fluid valve through which fluid can flow axially

Also Published As

Publication number Publication date
DE4421881A1 (en) 1996-01-04

Similar Documents

Publication Publication Date Title
EP0934459B1 (en) Fuel injection valve
DE19547406B4 (en) Fuel injector
WO1996000348A1 (en) Valve needle with filter element
WO1999043948A2 (en) Electromagnetically controlled valve
DE4325842A1 (en) Fuel injection valve
DE19744739A1 (en) Fuel injection valve for internal combustion engine
EP1114249B1 (en) Fuel injection valve
WO1999010648A1 (en) Fuel injection valve
EP0862781A1 (en) Fuel injection valve
EP1907689A1 (en) Fuel injector
WO2007073964A1 (en) Electromagnetically operated valve
EP3080434A1 (en) Fuel injection valve
EP1370765B1 (en) Fuel injection valve
DE102005061409A1 (en) Electromagnetic fuel injection valve for vehicles is closed by ball whose top fits against curved section at tip of valve needle
WO2009053219A1 (en) Fuel injection valve
DE10049033B4 (en) Fuel injector
DE10055483B4 (en) Fuel injector
EP1399669A1 (en) Fuel injection valve
DE19931822A1 (en) Fuel injector
DE10046306A1 (en) Fuel injector
DE102004010174B4 (en) Pressing composite of a metal part and a plastic part
EP1066468B1 (en) Fuel injection valve
WO2002050426A1 (en) Fuel-injection valve
DE102005037552B4 (en) Fuel injector
EP1309790B1 (en) Fuel injection valve

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): BR CN CZ JP KR RU US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase