EP0725215B1 - Fuel injection device working according to the solid energy accumulator principle, for internal combustion engines - Google Patents

Abstract

The fuel injection system has a unit for producing increase in pressure which includes an impingement device (25), e.g. a rear wall or a piston type stop. The impingement device is provided in a fuel storage element (6) arranged outside an injection pump (1), connected at a pressure line (2) between the injection pump and the injection nozzle (3). The storage element (6) includes a fuel storage chamber (22), in which a spring preloaded diaphragm (23) is arranged. One side of the chamber is arranged at a specified distance to the diaphragm.

Description

The invention relates to a device for injecting Fuel for internal combustion engines in the preamble of the claim 1 specified Art.

Injection devices, their electrically operated reciprocating pumps according to the so-called solid-state energy storage principle work, have a delivery piston or cylinder on accelerated along a certain path almost without resistance, usually fuel is moved before the delivery pressure is built up to spray the fuel through the injector is required. That way before the actual pressure build-up required for injection kinetic energy absorbed or stored, which then suddenly converted into a pressure increase in the fuel becomes.

In a so-called pump-nozzle element known from DD-PS 120 514, that according to the solid-state energy storage principle works, the housing is formed from a cylindrical block, which has a central bore in which the delivery piston the injection pump slides and the fuel delivery chamber forms. Concentric to this central hole is one deep narrow groove for receiving the coil driving the armature brought in. This unit injector is on the back completed by a closure piece, one as an inlet channel serving bore. There is a nozzle on the front attached, which is in communication with the fuel delivery chamber.

In the more recent DD-PS 213 472 this is a further development Pump-nozzle system described, with a housing, an excitation coil, an accelerator and a compression spring existing drive part that by means of a conveyor line is connected to an injection nozzle. With this unit injector the excitation coil immediately limits the space in which the accelerator body is moved back and forth so that no partition between the accelerator and the coil located. This ensures optimal energy input achieved by the coil on the accelerator. Such Training, however, is in pump-nozzle systems, which involve Fuel is in the space delimited by the coil as it is with a compact design based on the solid-state energy storage principle working injectors is not possible. There is also an immediate limitation of the range of motion of the accelerator or a corresponding one Anchors due to a coil are not practical because they are long-lasting Usages lead through the one sliding back and forth on the coil Body to wear on the inner coil wall, causing the Functionality of the entire device affected is pulled.

The invention has for its object a fuel injection device, those based on the solid-state energy storage principle works to create the very compact, simple can be produced and assembled.

The task is performed using a fuel injector solved the features of claim 1. Advantageous configurations the invention are specified in the subclaims.

Through a structural design of the injection nozzle device and the injection pump on the one hand and by the provision a housing cylinder located inside a common housing on the other hand, by a magnetic ring element in a section is divided which is an injection pump armature encloses both a very compact design of the Fuel injector achieved in which the Injection and nozzle device integrated in one housing is, as well as a very good energy input from the coil causes the anchor.

The injection device according to the invention consists of a few cylindrical parts that are easy to manufacture and assemble are.

Fig. 1 bis Fig. 3 schematisch im Längsschnitt nach dem Kraftstoff-Energiespeicher-Prinzip arbeitende Einspritzvorrichtungen,

Fig. 4 und Fig. 5 schematisch im Längsschnitt zwei Ausführungsbeispiele der erfindungsgemäßen Einspritzvorrichtung,

Fig. 6, 7 und 8 schematisch eine der erfindungsgemäßen Einspritzvorrichtung zuarbeitende Kraftstoffzuführeinrichtung für einen Motorstart und einen Motor-Notlauf ohne Batterie,

Fig. 9 bis 12b schematisch im Längsschnitt Dämpfungseinrichtungen für den Anker der Hubkolbenpumpe,

Fig. 13, 14 und 15 bevorzugte Ausführungsformen eines Einspritzventils der erfindungsgemäßen Einspritzvorrichtung im Längsschnitt, und

Fig. 16 eine Kraftstoffversorgungseinrichtung ohne Rückleitung zum Tank,

Fig. 17 schematisch eine bevorzugte Schaltung zur Ansteuerung der Spule der erfindungsgemäßen Einspritzvorrichtung.

The invention is explained in more detail by way of example with reference to the drawing. Show it:

1 to 3 schematically, in longitudinal section, injection devices working according to the fuel-energy storage principle,

4 and FIG. 5 schematically in longitudinal section two exemplary embodiments of the injection device according to the invention,

6, 7 and 8 schematically a fuel supply device for the injection device according to the invention for an engine start and an engine emergency operation without a battery,

9 to 12b schematically in longitudinal section damping devices for the armature of the reciprocating pump,

13, 14 and 15 preferred embodiments of an injection valve of the injection device according to the invention in longitudinal section, and

16 a fuel supply device without return line to the tank,

17 schematically shows a preferred circuit for controlling the coil of the injection device according to the invention.

With injection devices operating according to the solid-state energy storage principle is an initial almost resilient Partial stroke of the impact body of the injection pump is provided in the if necessary, fuel is displaced.

1 has an electromagnetic driven reciprocating pump 1 on a delivery line 2 is connected to a spray nozzle device 3. From the delivery line 2 branches off an intake line 4, which with a fuel reservoir 5 (tank) is connected.

The pump 1 is designed as a piston pump and has a housing 8, in which a magnet coil 9 is mounted, one in the area of the coil passage arranged anchor 10, which as a cylindrical body formed and in a housing bore or a cylindrical Housing interior 11 is guided, which is in the area the central longitudinal axis of the ring coil 9, and by means of a compression spring 12 is pressed into an initial position, in which it bears on the floor 11a of the interior 11. Supported is the compression spring 12 on the end face on the injection nozzle side of the armature 10 and one opposite this end face Ring step 13 of the interior 11. The spring 12 includes with play a delivery piston 14 which is connected to the armature 10 by the spring 12 loaded anchor face, e.g. in one piece, connected is. The delivery piston 14 plunges relatively deep into one cylindrical fuel delivery chamber 15, which is coaxial in axial Extension of the housing bore 11 is formed in the pump housing 8 and is in transmission connection with the pressure line 2 stands. Due to the immersion depth, pressure drops can occur during of the sudden pressure rise can be avoided, the Manufacturing tolerances between the piston 14 and cylinder 15 even can be relatively large, e.g. only in hundredths Millimeter range need to be, so that the manufacturing cost is low.

A check valve 16 is arranged in the intake line 4. In the housing 17 of the valve 16 is, for example, as a valve element a ball 18 arranged by in its rest position a spring 19 against its valve seat 20 on the reservoir side End of the valve housing 17 is pressed. To this end the spring 19 is supported on the one hand on the ball 18 and on the other hand on the wall of the valve seat 20 opposite Housing 17 in the area of the mouth 21 of the intake line 4th

The coil 9 of the pump 1 is connected to a control device 26, that as electronic control for the injector serves.

The armature 10 is in the de-energized state of the coil 9 Pump 1 by the bias of the spring 12 on the bottom 11a. The Fuel feed valve 16 is closed.

When the coil 9 is activated via the control device 26 the armature 10 against the force of the spring 12 in the direction of the injection valve 3 moves. The spring force of the spring 12 is relatively soft formed so that the armature 10 during the first partial stroke is accelerated almost without resistance. During the second Partial stroke takes place the pressure build-up and the spraying of Fuel instead, with armature 10 and piston 14 together move.

For the end of the delivery, the coil 9 is switched off. Of the Armature 10 is moved back to floor 11a by spring 12. At the same time, the fuel supply valve 16 opens, so that fuel is sucked out of the tank 5.

It is expedient in the pressure line 2 between the injection valve 3 and the branch 4 a valve 16a arranged, a stand pressure in the injector side space which e.g. is higher than the vapor pressure of the liquid at maximum temperature, so that bubbles form is prevented. The parking pressure valve can e.g. as the Valve 16 may be formed.

The delivery piston 14 is axially displaceable in the Anchor 10 stored. For this purpose, there is a graduated armature 10 Center longitudinal bore 108a in the manner of a blind hole formed, the blind hole end region of the bore 108a a has a smaller diameter than a central section and forms a stop ring step 108, in the central part the delivery piston 14 is guided by an integral with this trained guide ring 105, which has a larger diameter has as the delivery piston 14 and the expanded central bore area is adapted. The guide ring 105 of the delivery piston 14 is acted upon by a compression spring 106, which is relatively softly lined up and deals with her the other end at the bottom of the blind hole end portion of the bore 108a supported in the anchor 10. The guide ring is in the rest position 105 with its ring face on the delivery piston side by action the spring 106 on an annular stop surface 107 of the central Subrange, which acts as a step between that in diameter larger central bore section and that in diameter smaller bore portion is formed with the opening that the delivery piston 14 passes through.

1 works like follows. The anchor 10 is due during its first partial stroke accelerates the soft design of the spring 106 almost without resistance, the piston 14 remains at rest. After replacement of path "X" the ring step 108 of the bore 108a meets the Guide ring 105, which stores the stored kinetic energy of the armature 10 suddenly and suddenly transferred to the piston 14 which is this energy to the fuel in the pressure chamber 15, 2 emits, an increase in pressure being brought about in the fuel, that for spraying fuel through the nozzle device 3 leads.

The injection device shown in Fig. 2 has in the pressure line 2 also a check valve 16a, the structure of which corresponds to the check valve 16 and accordingly with a spherical valve element 117 and a return spring 118 is equipped. The purpose of this check valve is primarily in that in line 2 between nozzle 3 and Valve 16a maintains a static pressure in the fuel that e.g. higher than the vapor pressure of the liquid at the maximum occurring Temperature is.

Delivery piston 14 and armature 10 are relative to one another as in FIG. 1 slidably designed. For this purpose, anchor 10 a through bore 10a penetrated by the delivery piston 14 is formed. On the delivery piston 14 is at the free end that from the Armature 10 protrudes rearward, an annular stop 14a attached. Another stop ring 14b is located in the pressure chamber 15 of the delivery piston 14, the armature 10 between the two Stop rings 14a and 14b on the piston 14 with a gap "X" sits, indicating the possible acceleration stroke of the armature 10 marked. The armature return spring 12 engages over the stop ring 14b so that it is not disturbed by the ring 14b becomes.

The function of this embodiment of the injector corresponds to that of the injection device according to FIG. 1, the Armature 10 in this case the piston 14 via the rings 14a and 14b acted upon.

In those described above with reference to Figures 1 and 2 Embodiments of the injector will promote the fuel to the injector 3 by electromagnetic Generates power and the necessary for fuel intake Return movement of the conveyor element 14 and the armature 10 by the spring 12 causes. Can be used for special applications however, prove advantageous to reverse this principle, i.e. the delivery movement to the injector by spring force and To achieve suction motion electromagnetically against the spring force, with the electromagnetic force simultaneously for re-tensioning the spring ensures. A corresponding one preferred embodiment of the injection device according to the invention is shown in Fig. 3.

Regarding the system arrangement, that is shown in FIG. 3 Injector designed similar to the injector in FIG. 2. The injection pump 1 is connected to a pressure line 2 connected to the injector 3, in the pressure line 2 a check valve to prevent air bubbles 16a is arranged, which has the same structure as the check valve 16. The injection pump 1 becomes electromagnetic operated. For this purpose there is a coil 9 in the pump housing 8 arranged, and in the interior 11 of the housing 8 is axially movable the armature 10 arranged, the peripheral axially parallel has extending grooves 10b over which the areas of the interior 11 communicate with each other in front of and behind the anchor 10.

The armature 10 is relative to the delivery piston 14, the delivery piston axially movable penetrates a bore 10a in the armature 10. The delivery piston 14 faces away from the pressure chamber 15 End of the stop ring 14a which, as described in more detail below, a stop surface forms an active connection with an adjustable in the housing 8, and for example adjustable by a Baudenzug stop bolt 8a. At the other At the end, the delivery piston 14 projects into the delivery cylinder 15, the part of the delivery piston located in the interior 11 14 the stop ring 14b sits in the direction of the anchor 10 has an annular space 14c. There is a spring in the annular space 14c 14d mounted on the one hand on anchor 10 and on the other in the bottom of the annular space 14c.

The armature 10 is on its back by the return spring 12 applied, which is supported on the floor 11a of the interior 11, so that the armature 10 presses against the ring 14b and this against the ring line 13 of the interior 11 on the pressure line side presses. So that the rest position of the delivery piston 14 and Anchor 10 defined. The armature 10 is on the delivery piston 14 the path "X" is freely movable axially.

When the coil 9 is excited, the armature 10 is initially only against the spring 12 moves; after the path "X", the delivery piston 14 included in the armature movement and the suction stroke carried out. During the suction stroke, the inlet valve 16 and fuel open flows into the pump chamber 2, 15. The spring 14d ensures that the delivery piston 14 and the armature 10 no undesirable relative movements run against each other. Depending on the amount offered electrical energy arises at different Suction strokes a balance of forces between the spring 12 and the electromagnetic force. So that can be hosed down Amount of fuel over the amount of electrical energy supplied being controlled.

If the power supply is interrupted after a successful suction stroke, accelerates the spring 12 the anchor 10 initially without resistance on the path "X" towards the stop ring 14b. If the Anchor 10 hits the stop ring 14b, the kinetic Energy of the armature 10 on the delivery piston 14 and from here as Pressure energy on the fuel column in the delivery cylinder 15 and the subsequent pressure line 2 transmitted. It will Inlet valve 16 closed in the intake line 4, and that Pressure maintaining or check valve 16a begins to open.

The delivery piston 14 leads on its way to the possible Stop 13 from the actual delivery stroke, which for hosing of fuel passes through the injector 3 until the delivery piston with the front face in the conveying direction its annular extension 14b abuts the stop 13, which stops fuel delivery.

This type of construction enables one in particular over time short pressure surge caused by a defined delivery end is marked. This has significant advantages in two-stroke engines due to their particularly high speed allow only short mixture preparation times. Furthermore enables this type of operation with little modification Motors that have no defined electrical energy supply Provide how this is necessary for electronic control is. For example, an electromagnetic Coil, e.g. for simple ignition systems of small engines is common to be excited once per revolution and one Deliver current impulse, in its weakest form just that enables full anchor stroke. Used for quantity dosing in In this case, the stop 8a which adjusts the suction stroke and which this purpose in the simplest case with the throttle valve Motor is in mechanical connection.

The principle of solid-state energy storage for a fuel injection device has the main advantage that the Pressure increase in the pump system independent of the one to be sprayed Amount of fuel is very steep. This allows a small nozzle opening pressure because with the nozzle open, it's always a good thing Atomization of sufficiently high fuel pressure at the nozzle. This advantage is optimally exploited in that in FIG. 4 illustrated embodiment of the injection device according to the invention, where the delivery piston by hitting on a nozzle needle simultaneously opening and closing the Injector controls. It is also advantageous that the Height of the nozzle opening pressure and thus, for example, the usage-related No decrease in the spring force of the nozzle spring Influence on the amount of fuel sprayed.

The injection device shown in FIG. 4 sees a constructionally uniform Formation of the injector 3 and the injection pump 1 before. The common housing of the device is formed in several parts and consists essentially of one tubular internal housing cylinder 300, which in one Section that encloses the injection pump anchor 10 by a non-magnetic ring member 301 is divided so that on the armature 10 can be exerted by a coil 9. The two housing areas of the housing cylinder 300 are in the Area of the ring element 301 hydraulically tightly connected to one another, and the coil 9 is seated on the outer circumference of the housing cylinder 300, overlapping the ring element 301 in the axial direction.

There is also a cylindrical housing part 302 which surrounds the housing cylinder 300 and encloses the coil 9 from the outside. At the tank end is in the housing cylinder 300 a connector 303 screwed. The connector 303 has a through hole 305, which acts as a feed line for the Serves fuel, which is symbolized by the arrow in front of bore 305 becomes.

At the other pressure-side axial end of the housing cylinder 300 the injector 3 is inserted into a thread. Between nozzle 3 and connector 303 is a passage in the housing cylinder 300 provided with areas of different diameters. Subsequently the passage has its connection part 303 Area of greatest diameter on which the working space 306 for forms the armature 10 of the injection pump 1. This work space 306 is delimited on the tank side by an annular bottom surface 11a, which serves as a stop surface for the armature 10 when it is through the spring 12 is pushed into its rest position. In the direction The tank follows the bottom surface 11a of an enlarged diameter Bore 305, in which the inlet valve 16 is seated, the function of the feed valve 16 in Fig. 1 comes. The inlet valve 16 has a disk-shaped valve element 307, which by a Spring 308 is urged against its valve seat by the Annular surface is formed as a step between the through hole 305 and their diameter-enlarged area is. The spring 308 is supported at the other end on the armature 10.

The armature 10 is penetrated by a through hole 309, which is axially aligned with the bore 305 of the connecting part 303. The armature 10 has a reduced diameter area in the end area on the pressure side. The armature return spring 12 supports on the anchor 10 on the ring surface, which in the step area between the smaller diameter and larger diameter range the armature 10 is formed. The other supports Spring 12 on an annular surface in the housing cylinder 300th is formed on an inwardly projecting ring 300a the larger diameter working space 306 and in the direction of Nozzle 3 following smaller diameter pressure chamber 11 of the passage of the housing cylinder 300. The reduced diameter end region the armature 10 is designed so that it the ring 300a can take hold. The delivery piston 14 is seated in the pressure chamber 11 separate from the anchor. The delivery piston 14 is cylindrical Hollow body formed and has a cylindrical cavity 14e on, through axial bores 312, 313 with the pressure chamber 11 communicates. A pressure valve is located in the cavity 14e, that of a valve plate 310 and a valve plate 310 acting spring 311, the valve plate 310th is pressed against the bore 312. The valve plate 310 of the Pressure valve thus closes inlet 312 under spring force, wherein edge recesses 310a are made in the valve plate are.

The injection nozzle device 3 is in the housing cylinder 300 inserted at the end and includes a screwed plug-shaped Body 314 with central through bore 314a, the the tappet stem 315 of a valve tappet 317 passes through, the Ram plate 316 closes the exit of bore 314a. Of the Tappet plate 316 can thus be inserted into plug 314 Valve seat engage and under action a spring 318, which is on the one hand on an internal annular end face of the plug 314 and on the other a spring washer 315a supports the inner end of the plunger stem 317 is fixed.

The nozzle tappet stem 317 protrudes into the pressure chamber 11 of the housing cylinder 300 in which the delivery plunger 14 is located on the stopper 314 supporting spring 320 in its rest position against the Ring 300a is pushed, in which he with the anchor facing End face on a stop surface 321 of the ring 300a is present. With injector 3 closed and in the rest position conveyor piston 14 is left an axial distance "H" between the inner end of the plunger 317 and the opposite end face of the axially movable delivery piston 14.

The injector shown in Fig. 4 works like follows. The armature 10 is in the magnetic field generated via the coil 9 accelerated against the force of its return spring 12. During the acceleration stroke "X" (this is the axial one Distance between delivery piston 14 and armature 10, if these two Elements are in the rest position), can be in the pump work room 306 located fuel through the bore 309 flow the back of the armature. The anchor 10 strikes at the end of its Acceleration stroke "X" on the delivery piston 14, so the fuel in the pressure chamber 11 is suddenly compressed. Due to this pressure increase and the fact that the Delivery piston 14 strikes piston rod 315 after a stroke "H", the nozzle 3 is opened and fuel is sprayed off.

During the piston displacement phase, this opens on the back Anchor 10 located inlet valve 16 and fuel is from the Refueled fuel tank, not shown.

After the end of the spraying process, the delivery piston 14 by its return spring 320 in turn against its anchor side Stop 321 moves. At the same time, the nozzle needle closes 317 through their plate 316 the nozzle bore. With the return movement of the delivery piston 14 opens that arranged in it Pressure valve 310, 311 and fuel flow from armature space 306 in the pressure chamber 11 after.

A slightly modified injection device of the in Fig. The injection device shown in FIG. 4 is shown in FIG. 5, essentially only the reference numbers are entered are related to or related to the variation. The modification is that the plunger handle 315 in the Bore 313 passes through and into the interior 14e of the Delivery piston 14 projects, at the end of the plunger stem 315 Ring 322 is formed, which is a bearing of the spring in space 14e 311 of the pressure valve 311, 310 forms. In the bore 313 are edge grooves 313a introduced for the flow possibility of fuel.

In this embodiment of the invention, the tappet valve return spring 318 are dropped. When the delivery piston starts to move 14 takes place against the inertia of the nozzle needle 317 by the pressure in the fuel and the spring force of the spring 311 opening the nozzle 3. Otherwise, the function corresponds to 5 of that of FIG. 4th

With the help of the injection device according to the invention an engine start without battery and an engine emergency run without battery operate. 6, 7, 8, this possibility is in following described in more detail.

The electrically driven or electronically controlled injection requires sufficient electrical power to start and run Energy. In the event that the electrical energy is not in sufficient size is available should according to the invention the possibility to be created engines with the invention To start injection without electrical energy, for example using a hand crank drive. The fuel required is, as explained in more detail below, by an auxiliary device made available. If the engine reaches one Speed at which the generator provides sufficient energy, the fuel auxiliary device according to the invention switched off and the injection takes place electrically or electronically controlled, according to the normal case.

There are engines that start without electrical energy e.g. by hand or kick start device. This includes small ones Motors for hand tools, two-wheel vehicles or outboards. This starting device is required because none There is a battery for starting and / or running. About that In addition, engines should, for example, even when the battery is flat be bootable without electrical energy.

According to the invention, the possibility of motors without electrical To start energy by auxiliary means that the fueling condition present on each engine, e.g. the inlet gradient or the pressure of the fuel delivery pump Starting speed is used. The fuel becomes the intake manifold or the overflow in two-stroke engines or a metering device fed directly. Then the engine reaches one Speed at which the generator has sufficient energy for the Provides injection, a valve blocks the direct fuel supply to the engine, the fuel becomes the injector fed and this then takes over the fuel supply of the motor.

6 shows an arrangement for supplying fuel according to the invention of an engine 500. This is after a fuel back pressure pump 501, the intake side with a fuel tank 502 is connected, a branch of the fuel feed provided for the engine. One is on when de-energized a generator 503 connected injector 504, the constructed according to one of the above embodiments is inactive, and for example electromagnetic actuated control valve 505 is closed for the fuel supply an atomizer 506 on the engine 500 opened.

When the engine 500 starts, that of the pre-pressure pump 501 delivered fuel pressure via the opened control valve 505 to the atomizer 506 located on the motor 500. Of the Flow resistance of the control valve 505 and / or the atomizer 506 is dimensioned so that with the print offer the Admission pressure pump 501 at start speed the one required for the start Fuel requirements are met. Reaches that with the engine coupled generator 503 a speed at which the for Injector 504 meets required energy requirements is an injection control 507 active, which is also from Generator 503 is fed and via a control line to the Injector 504 is connected. To do this, use of a current signal, the control valve 505 closed, so that no More fuel can be fed directly to the engine. At the same time takes over the injector 504, controlled by the injection control 507, the injection via the injection nozzle 508.

A hand pump 509 present on many motors can optionally additionally during the starting process for the direct fuel supply can be used for the motor via the atomizer 506. The Hand pump 509 is in the connecting line 511 from the pump 501 arranged to the control valve 505. Actuation of the control valve 505 is carried out by the injection control 507 via a Control line 510.

Fig. 7 shows a modification of the arrangement of FIG. 6, in which the control valve 505 in the injection line 511 between the Injector 504 and the injector 508 arranged is. The function of stormless starting corresponds to that Function explained above with reference to FIG. 6.

In order for the fuel to flow through without pump support To ensure injector 504 is the flow resistance injector 504 is kept small. Advantageous is in the process of venting injector 504 and the injection line 511 is easily possible. Should the Injector 504 are vented, so the control valve 505 via an off switch 512 in the line from the Injection control 507 to control valve 505 de-energized, unless this has already been done by the injection control 507 is. As a result, the control valve 505 is in the direction of the atomizer 506 opened, and the air in the system can at simultaneous pumping, for example with the pre-pressure pump 501 or the hand pump 509.

8, the one provided according to the invention is described below Engine emergency running without battery are described in more detail.

The arrangement shown in FIGS. 6 and 7 can also for the Emergency operation of the engine can be used, for example insufficient power supply due to generator failure available for the injection control and the injection device is. According to the invention, this is done by a metering device, for example by an adjustable, with the Throttle valve in the air intake pipe coupled throttle in the control valve a quantity variation of the fuel, which is a control the engine load allowed makeshift.

Fig. 8 shows a suitable embodiment of the Control valve or the metering valve 505 in FIGS. 6 and 7. The control valve 505 has a housing 520 into which one Coil 521 is used to drive an armature 522 serves, which is displaceable in a bore 523 of the housing 520 is stored and in its rest position by a return spring 524 against an adjustable one arranged in the housing 520 Stop 525 is pushed to the outside of the housing Cable 526 is connected. Longitudinal grooves are peripheral in armature 522 527 formed which is a communication from in the bore 523 fuel present between the front and rear of anchor 522. The piston-shaped stop 525 passes through the housing end wall 520b and is in the Housing 520 by means of a spring 528 opposite the housing end wall 520b biased.

Uniformly formed with the one opposite the stop 525 The end face of the armature 522 is a metering piston 527. This The end face is also acted upon by the return spring 524, which is against the end wall 520a of the housing 520 supports. The dosing piston 527 protrudes with a tapered Spigot end in the delivery line 511, one of which is also Connection line 511a branches off to the atomizer 506.

The cable pull 526, which on the spring force against the armature 522nd preloaded stop 525 is connected to the throttle valve 530 (see Fig. 7, 8). The throttle position is thereby transferred directly to the stop 525.

The function of the control valve 505 is as follows. Im de-excited The state of the coil 521 is armature 522 and metering piston 527 by the return spring 524 on the stop 525. The fuel can come from the feed pump 501 through the feed line 511 flow to the atomizer 506. If the control valve 505 When excited by the controller, armature 522 pushes the Dosing piston 527 against the force of spring 524 as far as Direction of delivery until the inlet cross section 531 of the delivery line 511 is closed.

If the engine is operated in emergency mode without injection, the control valve 505 is de-energized and thus the inlet cross-section 531 released in line 511 to atomizer 506. Corresponding the conical metering piston becomes the throttle valve position 527 over the anchor 522 through the stop 525 more or pressed less far into the bore of the inlet cross section 531. The coupling to the throttle valve 530 is chosen so that with the opening of the throttle valve 530 of the cross section 531 more is opened. In the idle position of the throttle valve 530, a minimal gap remains on cross section 531, which is the Passes the idle amount of fuel to the atomizer 506.

The injection pump armature is reset in the Rule using the provided return spring. To great Achieving spray frequencies is the reset time of the armature to keep small. This can be done, for example, by a corresponding Realize the spring force of the return spring. With however, a reduction in the reset time increases the speed of impact of the anchor at the anchor stop. Disadvantageous the associated wear and / or that Bouncing the anchor on the anchor stop, reducing the total working time is enlarged. An object of the invention is therefore in the fall time of the anchor to the rest position to keep small. According to the invention, this goal is achieved by e.g. hydraulic damping of the armature return movement in the reached the last part of this movement.

Fig. 9 shows an embodiment of the injection pump, which in essentially has the structure of the injection pump 1 according to FIG. 1. For the hydraulic damping is like a piston cylinder arrangement at the back of the anchor 10 centrally cylindrical projection 10a formed in the last section the armature return movement in a blind cylinder bore 11b suitably enters the floor 11a, which on the stop surface 11a is formed for the armature 10 in the housing 8. Anchor 10 are longitudinal grooves 10b formed, the anchor back space 11 with the anchor front space 11 connect. There is a medium in room 11, e.g. Air or Oil flowing through the grooves 10b when the armature 10 moves can. The depth of the blind cylinder bore 11b corresponds approximately the length of the protrusion 10a (dimension Y in Fig. 12). Thereby, that the projection 10a immerse in the blind cylinder bore 11b the armature return movement becomes strong in the last section delayed, which results in the desired hydraulic damping of the Armature return movement is effected.

10a shows a variant of the hydraulic damping. Also in this embodiment, that of the delivery piston 14 penetrated pump chamber 11 in front of the Koblen 10 connected to the the anchor back adjacent space 11, through holes 10d that in the area of the back of the anchor in a central Overflow channel 10c open. A central pin 8a of a shock absorber 8b protrudes with its cone tip 8c towards the mouth of the overflow channel 10c, a hole 8d passes through in the rear Floor 11a, which opens into a damping space 8e, and ends in Insulation room with a ring 8f, which has a larger diameter has than the hole 8d. One on the floor of the damping room supporting spring 8g presses against the ring 8f and thus the Pin 8a in its rest position (Fig. 10a). A channel 8h connects the insulation space 8e with the rear anchor space 11. Die Channels 10c and 10d allow the armature 10 to be almost resistance-free Movement during the acceleration phase.

The damping device 8b is in the acceleration movement of the anchor 10 ineffective, so that no impairment of the Lifting phase. The mouth hits during the return movement the overflow channel to the cone tip 8c and is closed, so that the flow through the channels 10c and 10d is interrupted becomes. The armature 10 presses the pin 8a against the spring force and against the medium in room 8e, which is also in the Room 11 is located and flows out via channel 8h into room 11. The flows are chosen so that optimal damping is guaranteed:

Instead of the channel 8h, a displacement hole can be used according to FIG. 10b 8i be arranged centrally in the pin 8a, through the damping medium can be pressed into the overflow channel 10c.

According to a further advantageous embodiment of the invention Injector is provided in the return spring 12 of the armature 10 stored energy during the return movement of the anchor 10 to be used to advantage. This can According to the invention, for example, take place in that the anchor operated at the reset a pumping device for the Fuel supply to the injector for stabilization of the system and to prevent blistering or as a separate oil pump can be used for engine lubrication can. 11 shows a corresponding exemplary embodiment of a Oil pump 260 connected to fuel injection pump 1.

The fuel injector shown in Fig. 11 is in the 4 are designed according to FIG. and drain control element for controlling the first partial stroke of the delivery piston 14. The oil pump 260 is at the rear Bottom 11a of the pump housing 8 connected. In detail Oil pump 260 includes a housing 261 that mates with the housing 8 of the injection pump is connected, and in its pump chamber 261b a pump piston 262 is arranged, the piston rod 262a protrudes into the working space 11 of the armature 10, the Piston 262 is acted upon by a return spring 263 is supported on the housing base 261a in the region of an outlet 264.

In addition, the pump chamber 261b of the housing is over an oil supply pipe 265 in conjunction with an oil reservoir 266. A check valve 267 is inserted in the oil supply line 265, the structure of which is similar to that of valve 16 in FIG. 1.

The oil pump 260 works as follows. If the anchor 10 of the Injection pump 1 during its working stroke towards the Injector 3 moves, the pump chamber 11 in the housing 8th behind the armature 10 increased in volume, whereby the oil pump piston 262 is moved in the direction of the armature 10 and finally by the action of the return spring 263 in it Rest position is transferred. The storage container becomes 266 Via valve 267 oil into the working space 261b of the oil pump 260 sucked in. During the return movement of the armature 10 of the Pump 1 towards its stop 11a becomes the oil pump piston 262 at least on part of the return path of the armature 10 pushed into the oil pump chamber 261b. It is by the Pump pressure closed the valve 267 and there is oil over the Outlet 264 is discharged from the oil pump in the direction of arrow 264a and pressed to the parts of the engine to be supplied with oil.

The oil pump 260 can alternatively also be used as a fuel pressure pump are used, the fuel of the valve device 70 can be supplied. It is advantageous that the pump 260 can generate a static pressure in the fuel supply system, vapor bubble formation e.g. when the entire system heats up counteracts.

In addition, the formation of the additional effect according to the invention Pump 260 on pump 1 quick damping of the armature 10, so that the armature 10 does not rebound against the stop 11a.

Figures 12a and 12b show a particularly effective and simple Damping device. The structure of the pump device 1 is the same that shown in Figure 9. The blind cylinder bore 11b after Figure 12a is larger in diameter than the diameter of the cylindrical projection 10a. The projection 10a is from a sealing lip ring projecting in the direction of the blind cylinder bore 11b 10e surrounded by an elastic material which in the blind cylinder bore 11b fits. An insertion slope on the Mouth of the blind cylinder bore 11b facilitates the entry of the Lips the sealing lip ring 10e into the blind cylinder bore 11b. This damping device provides good damping when Stop of the armature 10 and hampers the acceleration stroke of the Anchor not. The elastic damping element 10e with axially parallel protruding sealing lips appear during the return stroke of the armature 10 in the blind cylinder bore 11b and lies against the outside of the inner wall of the blind cylinder bore 11b.

The blind cylinder bore 11b according to FIG. 12b has a diameter also larger than the cylindrical projection 10a. A sealing ring 10f made of elastic material sits on the Wall of the blind cylinder bore 11b and points in the area of Mouth inward-facing sealing lips 10g. In the elastic Sealing element 10f dips the cylindrical projection 10a a piston-like, the sealing lips 10g due to the outflowing Damping medium against the cylindrical projection 10a be pressed so that a particularly good damping of the armature 10 is reached.

13, 14 and 15 show particularly advantageous embodiments the injection nozzle (e.g. nozzle 3) for the invention Injector.

This injector includes a valve seat tube 701 on the other the free lower end of the membrane 704 is arranged, if necessary, a jet-forming pin insert 702 (which is shown in a central hole of membrane 704), a nozzle holder 703, a membrane plate 704 prestressed in the direction of the valve seat, a snap ring 705, a pressure line 706, the valve seat side into an open to the membrane 704 from the membrane covered ring channel 708 opens, a pressure screw 707, one Seal 709 for the nozzle holder 703 and a receptacle 710 for the nozzle holder 703.

With the membrane flat seat nozzle shown in FIGS. 13, 14 and 15 with nozzle spigot 702 (FIG. 14) and without nozzle spigot 702 (FIG. 15) will have a good atomization of fuel on the surface of an arched cone shell. The shape and dimensions of this coat include of the dimensions and design dependent on the outlet opening in the membrane (Fig. 14) and can if necessary with the help of a directional pin or throttle pin with the known functional advantages the requirements the engine operation can also be adjusted.

The valve works almost without moving masses and is through a specially designed metal membrane marked with a fixed flat valve seat works together. The Diaphragm - at the same time because of the preload valve spring - can through suitable, defined and permanent deformation against the Direction of opening (e.g. by arching). This allows fuel atomization at low pressures the nozzle opening through the central hole in membrane 704 is formed, e.g. at low speeds and small Injections (in low part load operation), improved will. Machining the nozzle hole (rounding the edges etc.) is easily possible from both directions.

To the good closing effect on the valve of the outward opening Reinforcing the injector can increase the seat ring width of the flat seat (Fig. 14) matched with the bias of the membrane plate will. The right choice of dimensions contributes to this of the lower ring groove in the valve seat, which results in given pressure of the fuel in front of the valve seat on the Membrane acting force results. On the other hand, the membrane due to the one in the ring groove or the one flowing through here Efficiently cooled fuel.

The nozzle requires no lubrication and is therefore for gasoline, Alcohol and its mixtures are particularly suitable. Due to the How it works - it is not downstream of the valve seat Volume available - are comparatively lower in this nozzle Hydrocarbon emissions from the engine are to be expected as with inward opening nozzles.

The nozzle consists of a few parts, their manufacture in mass production, Maintenance, checking and parts replacement is therefore very simple and inexpensive.

Fuel supply systems for fuel injection systems are used to cool and remove steam bubbles during flushed with fuel during operation. That is, the Fuel feed pump provides a larger amount of fuel ready than is needed by the engine. This extra amount is about a line is returned to the tank and is used for heat dissipation and for the removal of fuel vapor bubbles. Steam bubbles arise in engine operation due to heat and can affect the function disrupt or even prevent the injection system. Another one The still warm engine can be started by steam bubbles difficult or even prevented.

In certain engine applications, e.g. as an outboard motor Booting, however, is a return line to the tank for safety reasons not approved by law.

A fuel supply device with an inventive Fuel injector is after another Embodiment of the invention therefore without return line to the tank trained, while still heat and steam bubbles are removed can.

The invention solves this problem by using a second one Fuel pump, a gas separation chamber with a floating valve and a cooler. This arrangement can be attached directly to the engine and thus avoids pressurized fuel lines outside the engine compartment or the engine capsule. So that is the legal safety regulations are satisfied.

16, this fuel supply device explained in more detail below as an example.

A pump 801 sucks the fuel 802 from the tank 803 and guides it through a fuel line 804 to a gas separation chamber 805 to. The gas separation chamber 805 has a float 806, which operates a vent valve 807, which operates on a Ceiling area arranged above the liquid level 805a Gas discharge line 808 acts.

From the bottom of the gas separation chamber 805 is a fuel line 809 branched, which is connected to a pump 810 and leads to an injection valve 811 according to the invention, which via a fuel line 812 with the gas separation tank 805 connected above the liquid level 805a in the Gas separation container 805 opens. In the fuel line 812 As a result, a pressure regulator is located starting from the injector 811 813 and a cooler 814.

The new fuel supply device for an inventive Fuel injector works as follows: Pump 801 sucks fuel 802 from tanks 803 and feeds it to the gas separation chamber 805 until the vent valve 807 is closed by float 806. The pump 810 takes the fuel and at the bottom of the gas separation chamber 805 builds upstream of the 813 pressure regulator for the respective injection system required pressure on. In their funding characteristics is the pump 810 is designed to be used for cooling and flushing of the injector 811 required amount of fuel applies and over the cooler 814 of the gas separation chamber 805 feeds. Now vapor bubbles 805b are placed in the gas separation chamber 805 discharged, the fuel level 805a will decrease, the Float 806 opens the vent valve 807 until the Pump 801 has advanced to the original level 805a. The Vent valve 807 is connected to the air intake pipe 808 of the engine, so that the withdrawn from the air intake pipe Fuel vapors cannot get into the environment unburned.

Fig. 17 shows a preferred circuit for driving the Armature excitation coil of the injection pumps according to the invention, the ensures an optimal acceleration of the anchor.

It is known to meter the amount of fuel to be sprayed for example, time-controlled. A purely temporal Control, however, has proven to be disadvantageous because of that Time window, which is between minimum and maximum to be sprayed Fuel quantity is too small to be in the Differentiated and required engine range reproducible enough to master. About the invention however, pure intensity control of the current flow can be achieve a sufficiently differentiable quantity dosage.

In the case of the electromagnetic drive of the invention Fuel injectors is particularly excitation i.e. the product of the number of turns of the coil and the current of the Current that passes through the coil, determining for the electromechanical Energy conversion. That is, an exclusive one Controlling the current amplitude allows that Switching behavior of the drive magnet regardless of influences the coil heating and a fluctuating supply voltage to be clearly defined. So it bears one Control especially strong in engines fluctuating electrical voltage conditions and the different Temperature conditions bill.

17 shows a two-point control circuit according to the invention for the current amplitude of the pump drive coil 600 controlling Current. The drive coil 600 is connected to a power transistor 601 connected to a measuring resistor 602 Mass lies. At the control input of transistor 601, for example to the transistor base, is a comparator 603 with created its exit. The non-inverting input of the Comparator is acted upon by a current setpoint, for example is obtained by means of a microcomputer, and the inverting input of comparator 603 is on the side of the Measuring resistor connected, which is connected to the transistor 601 is.

To the energy flow in the drive coil 600 regardless of the To control the supply voltage is that recorded by the coil 600 Current measured through the measuring resistor 602. Reached this current is the current setpoint from a microprocessor predetermined limit value, the comparator switches over the power transistor 601 the current for the coil 600. Once the Current actual value falls below the current setpoint, the transistor switches the coil current again via the comparator. By the inductance of the coil 600 due to the current rise delay prevents the maximum permissible from being exceeded too quickly Current.

Then the next switching cycle can begin, and this clocking of the coil current of coil 600 takes place as long as that the reference voltage supplying the current setpoint at the non-inverting Input of the comparator 603 is present.

The circuit represents a clocked current source, the Clocking only after reaching the one provided by the microprocessor Current setpoint. The energy and therefore the Quantity control of the pump device 1 can be done with this circuit in combination of the duration and / or amount of that of the microprocessor provided reference voltage.

Claims (39)

1. Fuel injection device which works according to the solid-body energy storage principle, in which an armature element (10) guided in a pump housing of an electromagnetically driven reciprocating piston pump (1) is accelerated almost without resistance, such that the armature element (10) accumulates kinetic energy and then comes up against a piston element (14) so that a pressure pulse is produced in the fuel present in a closed pressure chamber ahead of the piston element (14), inasmuch as the stored kinetic energy of the armature element (10) is transferred via the piston element (14) to the fuel present in the pressure chamber, and the pressure pulse is used to eject fuel through an injection nozzle device (3), the injection nozzle device (3) and the injection pump (1) being constructed as an individual unit,
   characterized in that
   a housing cylinder (300) located inside a common housing, which encloses the injection pump armature (10) in one section, is divided by a non-magnetic ring element (301) so that a force can be exerted on the armature (10) by a coil (9) positioned on the outer circumference of the housing cylinder (300).
2. Mechanism according to Claim 1,
   characterized in that
   the two housing sections of the housing cylinder (300) (301) are hydraulically connected to one another in a leak-proof way in the area of the ring element and the coil (9) extends across the ring element (301) in the axial direction.
3. Mechanism according to Claim 1 and/or Claim 2,
   characterized in that
   it comprises a cylindrical housing component (302) which surrounds the housing cylinder (300) and encloses the coil (9) from the outside.
4. Mechanism according to one or more of Claims 1 to 3,
   characterized in that
   at the tank-side end in the housing cylinder (300) a connection piece (303) is screwed in, which has a through-bore (305) that serves as an inlet pipe for the fuel.
5. Mechanism according to one or more of Claims 1 to 4,
   characterized in that
   at the axial end of the housing cylinder (300) on the pressure side, the injection nozzle device (3) is fitted in a screw-thread.
6. Mechanism according to one or more of Claims 1 to 5,
   characterized in that
   between the nozzle device (3) and the connection piece (303) in the housing cylinder (300) a passage with sections of different diameters is provided, the section of largest diameter being adjacent to the connection piece (303) and forming the working space (306) for the armature (10) of the injection pump (1).
7. Mechanism according to Claim 6,
   characterized in that
   the working space (306) is bounded on the tank side by an annular bottom surface (11a) which serves as an end-stop surface for the armature (10) when the latter is pushed by the spring (12) to its rest position, and in the tank direction of the bottom surface (11a) the diameter of the bore (305) increases to accommodate an inlet valve (16).
8. Mechanism according to Claim 6 and/or Claim 7,
   characterized in that
   the armature (10) is penetrated by a through-hole (309) axially aligned with the bore (305) of the connection piece (303), the armature has a section of reduced diameter at its end on the pressure side, the armature return spring (12) rests on the armature (10) against the annular surface formed by the step between the parts of the armature with smaller and larger diameters, and at its other end the spring (12) rests against an annular surface formed in the housing cylinder (300), on an inwards-projecting ring (300a) between the working space (306) of larger diameter and the pressure chamber (11) of smaller diameter beyond it along the through-passage of the housing cylinder (300) in the direction of the nozzle device (3).
9. Mechanism according to Claim 8,
   characterized in that
   the end section of the armature (10) having reduced diameter is designed so that it can pass through the ring (300a).
10. Mechanism according to Claim 9,
    characterized in that
    in the compression chamber (11) the delivery piston (14) is located separately from the armature (10), it is constructed as a cylindrical hollow body, and it comprises a cylindrical hollow space (14e) which communicates via axial holes (312, 313) with the pressure chamber (11), a pressure valve being located in the hollow space (14e), the said valve consisting of a valve disc (310) and a spring (311) that acts on the valve disc (310).
11. Mechanism according to one or more of Claims 1 to 10,
    characterized in that
    the injection nozzle device (3) is located in the housing cylinder (300) at the front end and comprises a screwed-in stopper-shaped body (314) with a central through-hole (314a), through which passes the tappet rod (315) of a valve tappet (317) whose tappet disc (316) closes off the outlet of the hole (314a).
12. Mechanism according to Claim 11,
    characterized in that
    a spring (318) acts on the valve tappet (317), which rests at one end against an inwards projecting annular front surface of the stopper (314) and at the other end against a spring disc (315a) located on the inwards-directed end of the tappet rod (317).
13. Mechanism according to Claim 12,
    characterized in that
    the nozzle tappet rod (315) projects into the pressure chamber (11) of the housing cylinder (300) in which the delivery piston (14) is pushed against the ring (300a) by the spring (320) resting against the stopper (314), where it rests with its end surface facing towards the armature against a contact surface (321) of the ring (300a).
14. Mechanism according to one or more of Claims 1 to 13,
    characterized in that
    the tappet rod (315) passes through the hole (313) and projects into the inside space (14a) of the delivery piston (14), and a ring (322) is formed at the end of the tappet rod (315), which in the space (14e) forms a contact surface for the spring (311) of the pressure valve (311, 310).
15. Mechanism according to Claim 14,
    characterized in that
    grooves (313a) are formed around the rim of the hole (313).
16. Mechanism according to one or more of Claims 1 to 15,
    characterized in that
    it comprises an auxiliary starting device which comprises a control valve connected to an atomizer (506) of the engine (500) and supplied with fuel from the fuel tank (502), the flow resistance of the said valve together with that of the atomizer (506) being determined such that, with the pressure produced by a pre-pressurizing pump (501) at the starting speed of revolution, the fuel required for starting can be supplied to the injection device (504) even without any input of electrical energy.
17. Mechanism according to Claim 16,
    characterized in that
    downstream from the fuel pre-pressurizing pump (501), which on the suction side is connected to the fuel tank (502), the fuel line to the engine comprises a branching point, such that when no current is connected an injection device (504) constructed according to the invention and in particular as an example embodiment thereof, is inactive and the - for example - electromagnetically activated control valve (505) for the supply of fuel to the atomizer (506) on the engine (500) is open.
18. Mechanism according to Claim 16 and/or Claim 17,
    characterized in that
    a hand pump (509) present on the engine is additionally used during the starting process for the direct supply of fuel to the engine via the atomizer (506), the said pump being fitted in the connection line (511) from the pump (501) to the control valve (505), such that the regulation of the control valve (505) by the injection control device (507) takes place via a control line (510).
19. Mechanism according to Claim 16,
    characterized in that
    the control valve (505) is positioned in the injection line (511) between the injection device (504) and the injection nozzle (508).
20. Mechanism according to Claim 19,
    characterized in that
    it comprises a cut-out switch in the line from the injection control device (507) to the control valve (505).
21. Mechanism according to Claim 19 and/or Claim 20,
    characterized in that
    the auxiliary starting device according to the invention is used for emergency starting of the engine, whereby a metering valve (505) varies the quantity of fuel.
22. Mechanism according to one or more of Claims 16 to 21,
    characterized in that
    the metering valve (505) comprises a housing (520) in which there is a coil (521) which drives an armature (522) that can slide within a bore (523) of the housing (520) and in its rest position is pressed by a restoring spring (524) against an adjustable end-stop (525) in the housing (520), to which a cable pull (526) is connected outside the housing, and peripheral longitudinal grooves (527) are formed in the armature (522) which allow communication of the fuel present in the bore (523) between the front side and the rear side of the armature (522), and the piston-shaped end-stop (525) passes through the end wall of the housing (520b) and in the housing is pressed against the end wall of the housing (520b) by a spring (528), and a metering piston (527) is formed as one unit with the end of the armature (522) opposite the end-stop (525), and this end is also acted upon by the restoring spring (524), whose other end rests against the end wall (520a) of the housing (520), and the metering piston (527) projects with a conical tip into the delivery line (511), from which in addition a connection line (511a) branches off to the atomizer (506), and the cable pull (526), which is connected to the end-stop (525) held under spring force against the armature (522), is connected to the throttle valve (530).
23. Mechanism according to one or more of Claims 1 to 22,
    characterized in that
    it comprises a hydraulic damping device for the armature element (10) of the reciprocating piston pump.
24. Mechanism according to Claim 23,
    characterized in that
    the hydraulic damping device is constructed as a piston and cylinder arrangement, such that on the armature (10) a central cylindrical projection (10a) is formed, which moves into a blind cylinder bore (11b) in the bottom (11a) of the cylinder during the last section of the armature's return movement, and the armature (10) has longitudinal grooves (10b) which connect the space behind the armature with the space in front of the armature in the pump cylinder.
25. Mechanism according to Claim 23,
    characterized in that
    the pump space (11) through which the delivery piston (14) passes ahead of the piston (10) is connected to the space (11) adjacent to the back of the armature by holes (10d), which open into a central overflow channel (10c) in the area at the back of the armature, and a central pin (8a) of a shock-absorber (8b) with a conical tip (8c) projects in the direction of the mouth of the overflow channel (10c).
26. Mechanism according to Claim 25,
    characterized in that
    at its back end the central pin (8a) passes through a hole (8d) in the bottom (11a), the said hole opening into a damping space (8e), and inside the damping space the pin (8a) ends in a ring (8f) whose diameter is larger than that of the hole (8d), and a spring (8g) rests against the bottom of the damping space, which presses against the ring (8f), and a channel (8h) connects the damping space (8e) with the space (11) at the back of the armature.
27. Mechanism according to Claim 25,
    characterized in that
    a displacement hole (8i) is formed centrally in the pin (8a), through which the damping medium can be pressed into the overflow channel (10c).
28. Mechanism according to Claim 23,
    characterized in that
    during its return movement the armature (10) acts as a pump device which at the same time constitutes a damping device for the armature (10).
29. Mechanism according to Claim 28,
    characterized in that
    an oil pump is connected to the bottom (11a) at the back of the pump housing (8), which comprises a housing (261) in whose pump space (261b) is located a pump piston (262) whose piston rod (262a) projects into the working space (11) of the armature (10), and the piston (262) is acted upon by a restoring spring (263) which rests against the bottom of the housing (261a) in the area of an outlet (264).
30. Mechanism according to Claim 29,
    characterized in that
    the pump space (261b) is connected via an oil supply line (265) to an oil reservoir (266), and a non-return valve (267) is fitted in the oil supply line (265).
31. Mechanism according to Claim 23 and/or Claim 24,
    characterized in that
    the blind cylinder bore (11b) has a diameter larger than that of the cylindrical projection (10a) and the projection (10a) or the blind cylinder bore (11b) comprises a sealing lip ring (10e), such that the sealing lip rings form the piston seal for the projection (10a).
32. Mechanism according to one or more of Claims 1 to 31,
    characterized in that
    it comprises an injection nozzle with a valve seat tube (701) having an annular channel (708) at its end, a membrane plate (704) with a central hole prestressed in the direction of the valve seat, the said membrane plate covering the annular channel (708), if needs be with a pin insert (702) in the hole of the membrane (704), a clip-ring (705) and a pressure pipe (706).
33. Mechanism according to one or more of Claims 1 to 32,
    characterized in that
    it comprises a fuel supply device without a return line to the tank, such that a second fuel pump, a gas separation chamber with a float valve and a cooler are used.
34. Mechanism according to Claim 33,
    characterized in that
    it comprises a gas separation chamber (805) into which fuel is pumped from a tank (803) by a pump (801) via a pipe (804), from which by means of a pump (810) and via a fuel line (809) fuel is supplied to an injection valve (811), and from the injection valve (811) a pipe (812) leads back into the gas separation chamber (805), in which a pressure regulator (813) and a cooler (814) are arranged, and a float (806) is provided in the gas separator (805), which operates a venting valve (807) fitted in an outlet pipe (808) that opens into the gas separation chamber (805).
35. Mechanism according to Claim 33,
    characterized in that
    the fuel pipe (812) opens into the gas separator chamber (805) above the liquid level (805a).
36. Mechanism according to Claim 34 and/or Claim 35,
    characterized in that
    the vent pipe (808) opens into the gas separation chamber (805) above the liquid level (805a).
37. Mechanism according to one or more of Claims 33 to 36,
    characterized in that
    the fuel line (804) opens into the gas separation chamber (805) above the liquid level (805a).
38. Mechanism according to one or more of Claims 33 to 37,
    characterized in that
    apart from the tank (803) all the components of the fuel injection system are located inside the engine compartment (815).
39. Mechanism according to one or more of Claims 1 to 38,
    characterized in that
    it comprises a circuit to control the armature activating coil (9, 600), which is connected to a power transistor (601 in turn connected to earth via a measurement resistance (602), such that the output of a comparator (603) is connected to the control input of the transistor (601), for example to the transistor base, and the non-inverting input of the comparator (603) is fed with a current of nominal value, for example derived from a microprocessor, while the inverting input of the comparator (603) is connected to the side of the measurement resistance that is connected to the transistor (601).

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