DE102007035695A1 - Fuel injection valve device for internal combustion engine, has valve needle, which controls injection opening by its longitudinal movement of opening and with control chamber, whose pressure indirectly affects valve needle - Google Patents

Abstract

The fuel injection valve device has a valve needle (10), which controls an injection opening (12) by its longitudinal movement of the opening and with a control chamber (20), whose pressure indirectly affects the valve needle. A discharge channel mouth is averted from the control chamber, which is arranged outside the guide pin in the control valve body.

Description

The The invention relates to a fuel injection valve device according to Preamble of claim 1.

State of the art

From the European patent application EP 1 612 403 A1 a fuel injection valve device with a valve body is known, from which a guide pin, which serves to guide a control sleeve. Through the control valve body, a flow channel extends into the guide pin.

task The invention is a fuel injection valve device to provide according to the preamble of claim 1 which is inexpensive to produce and, in particular in Area of the control valve body, a higher strength has as conventional fuel injection valve devices.

The Task is by a fuel injection valve device with the features of claim 1 solved. Special embodiments of the Invention are disclosed in the subclaims.

Advantages of the invention

The laying of the drainage channel opening out of the guide pin or away from the guide pin provides the advantage that the guide pin not, as in the from EP 1 612 403 A1 known fuel injection valve device is weakened by the flow channel, which is advantageous for strength reasons. Therefore, the diameter of the guide pin can be reduced.

One preferred embodiment of the fuel injection valve device is characterized in that the flow chamber mouth facing away from the control chamber, at least partially, radially outside the seat diameter is arranged. Preferably, the drain port is arranged on a diameter that is slightly larger as the seat diameter is.

One Another preferred embodiment of the fuel injection valve device is characterized in that the sealing seat for the control sleeve is provided on a seat plate through which the Guide pin extends. Preferably, the seat plate a through hole through which the guide pin extends through. The guide pin can with a preferably be provided ground leadership. In selecting of the material of the seat plate is to pay attention that the material is suitable for forming a valve seat on the seat plate.

One Another preferred embodiment of the fuel injection valve device is characterized in that the seat plate integral with a housing body of the fuel injection valve device is executed. When selecting the material of the case body make sure that the material to form a valve seat to the seat plate is suitable.

One Another preferred embodiment of the fuel injection valve device is characterized in that the drainage channel at the drainage channel mouth opens into an annular space between the seat plate and the control valve body is formed. Preferably the annulus between a substantially frustoconical connection region, through which the control valve body integral with the guide pin is connected, and one of them spaced apart Reduction at the control valve body end facing formed of the through hole of the seat plate.

One Another preferred embodiment of the fuel injection valve device is characterized in that an inlet channel into the annulus empties. The inlet channel is from the high pressure inlet, is equipped with a throttle and allows a faster Filling the annulus and the control room.

One Another preferred embodiment of the fuel injection valve device is characterized in that the guide pin in the area the seat plate is designed as multi-flat. The multi-flat allows the passage of fuel from the annulus between the guide pin and the seat plate to the sealing seat. In addition, the multi-flat serves as a guide.

One Another preferred embodiment of the fuel injection valve device Is characterized in that the seat plate together with the Control valve body by means of a clamping nut with the Injector body is clamped or screwed. Preferably, in this embodiment, between the valve needle, which is also referred to as a nozzle needle, and a valve piston formed a pressure stage. In fuel injection valve devices without such a pressure stage, the seat plate and the control valve body need not to be screwed.

A further preferred embodiment of the fuel injection valve device is characterized in that on the control sleeve radially inward a circumferential sealing edge or a sealing lip is provided, which comes to rest on the seat plate. This allows a conical seat, at the sealing edge provided on the control sleeve preferably comes to bear radially on the inside in a sealing manner on a diameter of the seat plate. Due to the width of the alternative sealing lip, the maximum sealing width can be specified.

One Another preferred embodiment of the fuel injection valve device is characterized in that the control sleeve one of the seat plate facing end face, which at an angle to the seat plate is arranged. This allows a flat seat. The angle, which is also referred to as seat angle difference, can be ground in the seat plate.

drawing

In the drawing are various embodiments of the illustrated fuel injection valve according to the invention. Show it:

1 a longitudinal section through a fuel injection valve with schematically shown supply components;

2 an enlarged section 1 according to a first embodiment of the invention with a provided on a valve seat plate valve seat;

3 to 5 three different embodiments of a valve seat;

6 a section from 2 with an additional inlet channel;

7 a similar representation as in 2 according to a further embodiment and

8th a section from 7 according to a further embodiment.

Description of the embodiments

In 1 a fuel injection valve according to the invention with the fuel-supplying components is shown schematically in longitudinal section. The fuel injection valve comprises a holding body 1 and a nozzle body 2 passing through a clamping nut 3 be pressed against each other. In the nozzle body 2 is a nozzle needle 10 arranged longitudinally displaceable, the opening of at least one injection opening for their longitudinal movement 12 controls. The fuel becomes the injection ports 12 over a pressure room 14 supplied to the valve needle 10 surrounds and the via an inlet channel 15 can be filled with fuel under high pressure. Moves the valve needle 10 from the injection ports 12 away and thus moves into its open position, fuel is from the pressure chamber 14 over the injection openings 12 injected into a (not shown) combustion chamber of the internal combustion engine. Is the valve needle located 10 in contrast, in its closed position, that is in contact with a valve seat, so are the injection openings 12 through the valve needle 10 locked.

In the holding body 1 is a longitudinal bore 5 formed coaxially with the valve needle 10 runs and in which a valve piston 7 is arranged longitudinally displaceable. The valve piston 7 lies over a pressure piece 19 at the valve needle 10 on, so that it synchronizes with the valve needle 10 moved in the longitudinal direction. At the nozzle body 2 facing end is the valve piston 7 from a spring 17 surrounded on the one hand in a paragraph in the holding body 1 supported and on the other hand on the pressure piece 19 , so by the force of the spring 17 the pressure piece 19 in the direction of the nozzle and thus the valve needle 10 is pressed into its closed position.

To supply the fuel under high pressure is a high pressure pump 6 provided the fuel from a fuel tank 4 compressed and a high-pressure accumulator 11 feeds, in which the fuel is kept under high pressure. Via a high pressure line 9 and a high pressure connection 8th , which is formed on the fuel injection valve, the high-pressure fuel is supplied to the fuel injection valve and in the manner described on the injection openings 12 injected into the combustion chamber of the internal combustion engine.

With his the nozzle 2 opposite end of the control piston limited 7 a control room 20 that has an inlet hole 21 in which there is an inlet throttle 22 located, with the inlet channel 15 connected is. The control room 20 is beyond a longitudinal bore 28 in the holding body 1 and in a control valve body 27 is formed, with a leakage oil chamber 32 connectable. For this purpose, the longitudinal bore opens 28 in a transverse bore 29 , in turn, in an annular groove 34 ends. In the longitudinal bore is an outlet throttle 24 intended.

For lowering the fuel pressure in the control room 20 serves a control valve 25 , The control valve 25 comprises a control valve member in the form of a control sleeve 30 comprising a piston-shaped portion of the control valve body 27 surrounds and is guided on this. The control sleeve 30 is in this case longitudinally movable and is in its closed position on a sealing seat, so that the annular groove 34 against the leak oil room 32 is sealed. The control sleeve 30 is from a closing spring 31 subjected to a closing force on the sealing sleeve 30 exercises and pushes against the seal seat. About an electromagnet 35 can the sealing sleeve 30 be lifted off the sealing seat, leaving the annular groove 34 and thus over the cross hole 29 and the longitudinal bore 28 also the control room 20 be connected to the leakage oil room.

The operation of the fuel injection valve is well known from the prior art and will be touched here only briefly. For an injection, the electromagnet 35 energized and thereby pulls the sealing sleeve 30 away from the seal seat. This will cause the annular groove 34 with the leakage oil room 32 connected, in which there is always a low fuel pressure. About the cross hole 29 and the longitudinal bore 28 becomes the control room 20 relieved of pressure, allowing the hydraulic force on the valve piston 7 lowered and the nozzle needle 10 caused by the fuel pressure in the pressure chamber 14 experiences a force in the opening direction, lifts off the valve seat and the injection openings 12 releases. To terminate the injection, the electromagnet is in turn de-energized, so that the sealing sleeve 30 , driven by the closing spring 31 , gliding back into contact with the sealing seat. Due to the inflowing fuel via the inlet bore 21 the pressure in the control room increases 20 again and thus the hydraulic force on the valve piston 7 so that it eventually moves towards the nozzle and thereby the nozzle needle 10 pushes back to its closed position.

At the control valve 25 the in 1 shown fuel injection valve device is a pressure balanced 2/2-way solenoid valve. The guide of the control sleeve 30 is directly part of the control valve body 27 , which is also referred to as a valve piece. A similar fuel injection valve device is in the European patent application EP 1 612 403 A1 described. This design has the disadvantage that the high pressure supply takes place within the seat line to the valve seat via a bore in the guide pin.

In the in the 2 to 8th illustrated embodiments of the invention is the valve seat 58 laid in a separate component. This has the advantage that the high-pressure inlet or the outlet channel mouth to the valve seat can no longer be arranged within the seat line, but on a slightly larger diameter. This provides the advantage that the diameter of the guide pin can be reduced. In addition, the guide pin must not be weakened by the outlet throttle, which is advantageous for strength reasons.

In 2 is a section of 1 shown enlarged according to a first embodiment. From the longitudinal bore 28 , which is designed as a blind hole, extends a sloping drain channel 41 with a drain throttle 42 in an annulus 44 between a frusto-conical connecting portion of a valve piece 45 a control valve body 46 from which a guide pin 48 goes out, and a seat plate 50 is trained. The seat plate 50 includes a central through hole through which the guide pin 48 extends through. Radial outside is the seat plate 50 between a clamping nut 51 that with the holding body 1 is bolted, and a paragraph 52 of the holding body 1 screwed. Between the seat plate 50 and the paragraph 52 is a covenant 53 clamped by the valve piece 45 of the control valve body 46 emanates.

On the guide pin 48 is in the area of the seat plate 50 a triple flat 55 formed, on the one hand for guiding or positioning of the seat plate 50 on the guide pin and on the other hand, the passage of fuel from the annulus 44 to a valve seat 58 allows, on the seat plate 50 is trained. The valve seat 58 on the seat plate 50 cooperates with a sealing edge, which at the combustion chamber near the end of a control sleeve 59 is provided.

At the combustion chamber remote end of the control sleeve 59 is a covenant 60 formed, which forms an anchor and with an electromagnet 61 interacts. When the electromagnet 61 energized, then becomes the anchor 60 to the electromagnet 61 tightened so that the at the combustion chamber near the end of the control sleeve 59 formed sealing edge of the sealing seat 58 takes off. The anchor 60 is by an anchor spring 62 from the electromagnet 61 biased away, so that at the combustion chamber near the end of the control sleeve 59 formed sealing edge in the de-energized state of the electromagnet 61 in contact with the sealing seat 58 on the seat plate 50 is held. The armature stroke of the anchor 60 is by a stroke stop 64 limited.

In the 1 shown plastic injection valve device, which is also referred to as an injector, is on the channel to run 15 filled with fuel under high pressure. About the inlet throttle 22 the fuel enters the control room 20 , From the control room 20 the fuel passes over the longitudinal bore 28 and the drainage channel 41 with the outlet throttle 42 in the annulus 44 , The exit point of the outlet throttle 42 or the drainage channel mouth into the annulus 44 is according to an essential aspect of the invention outside the seat diameter of the valve seat 58 , This has the advantage that the outlet throttle 42 can be installed in an area where there is sufficient space for production and a reasonable throttle geometry with diffuser. From the annulus 44 the fuel passes between the preferably ground triflate 55 of the guide pin 48 and the seat plate 50 to the valve seat 58 ,

As long as the control valve is not activated, that is as long as the solenoid 61 not be is energized, becomes the anchor 60 over the anchor spring 62 in the valve seat 58 pressed. As the guide pin 48 of the valve piece 45 from below through the seat plate 50 pushed, and the anchor 60 a very close leadership 56 to the guide pin 48 has, the hole must be in the seat plate 50 depending on the production cost either equal to the diameter of the guide 56 or slightly larger. That means for the valve seat 58 that is not sealed exactly edge to edge, but that under certain circumstances, a slight offset of a few micrometers must be accepted. When designing the seat geometry, this must be taken into account. A small diameter difference between the hole in the seat plate 50 and the guide diameter 56 can also be used as an easy-opening pressure stage.

In 3 is shown that the valve seat ( 58 in 2 ) as a conical seat on the control sleeve 59 may be executed, the inside sealing on the diameter of the seat plate 50 rests.

In 4 is the valve seat ( 58 in 2 ) as a flat seat with a seat angle difference 66 executed in the seat plate 50 is ground.

In 5 is the valve seat ( 58 in 2 ) as a flat seat without seat angle difference with a sealing lip 68 executed. Through the width of the sealing lip 68 the maximum sealing width can be specified.

If the in 2 With 61 designated solenoid is driven, then the anchor 60 against the spring force of the armature spring 62 Pulled up and hits on his upper stroke stop 64 at. The fuel can through the open valve seat 58 escape, causing the control room 20 relieved of pressure. By the pressure relief in the control room 20 raises the nozzle needle 10 with its tip off the associated nozzle needle seat and fuel is injected. When the valve ( 25 in 1 ) is closed again, pressure builds up again in the control room 20 on and the injector or the fuel injection valve closes.

In 6 an embodiment is shown in which the annulus 44 via an additional inlet channel 70 with an inlet throttle 71 with the inlet channel 15 communicates. The additional inlet channel 70 allows faster filling of the annulus 44 and the control room 20 ,

In 7 is shown that it may be sufficient depending on the embodiment, if only the seat plate 50 with the help of the clamping nut 51 against the paragraph 52 of the holding body 1 is tense. At the in 7 illustrated embodiment comprises a control valve body 74 a valve piston guide sleeve 75 extending from a valve piece 76 extends to the combustion chamber. In the valve piston guide sleeve 75 is a combustion chamber remote end of a valve piston 7 led the control room 20 in the valve piston guide sleeve 75 limited.

An inlet hole 77 extends through the valve piston guide sleeve 75 and creates a connection between the inlet channel 15 and the control room 20 , In the inlet hole 77 an inlet throttle is provided. Through the valve piece 76 extends a drainage channel 78 having an outlet throttle and outside of the guide pin 48 that of the valve piece 76 goes out, in an annulus 79 empties.

At the combustion chamber near the end of the valve piston guide sleeve 75 is a nozzle needle spring 81 on which the control valve body 74 in sealing contact with a sealing seat 80 holding on to the seat plate 50 is trained. In the starting case, in which the pressure in the injector must first build up, the valve piece 76 from the nozzle needle spring 81 against the seat plate 50 pressed and forms there the sealing seat 80 , During operation of the injector, the valve piece becomes 76 pressed in all operating cases of the prevailing pressure up and remains securely in position.

In 8th is hinted that even a seat plate 85 can be used, which is integral with the holding body 1 connected is.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1612403 A1 [0002, 0005, 0028]

Claims (10)

Fuel injection valve device with a valve needle ( 10 ), which by their longitudinal movement, the opening of at least one injection port ( 12 ) and with a control room ( 20 ), whose pressure is at least indirectly on the valve needle ( 10 ), the control room ( 20 ) through a drainage channel ( 28 ; 41 ) with a pressure relief space ( 41 ; 78 ), which flow channel ( 41 ; 78 ) by means of a control valve ( 25 ) can be opened or closed and a control room ( 20 ) facing away from the drain port, wherein the control valve ( 25 ) a control sleeve ( 30 ; 58 ), which by a closing force in the direction of a sealing seat ( 59 ) is pressed with a seat diameter and on a guide pin ( 48 ) is slidably mounted, of a control valve body ( 46 ; 74 ), characterized in that the control room ( 20 ) facing away from the drain port muzzle ( 48 ) in the control valve body ( 46 ; 74 ) is arranged. Fuel injection valve device according to claim 1, characterized in that the control chamber ( 20 ) facing away from the drain port, at least partially, radially outside the seat diameter is arranged. Fuel injection valve device according to one of the preceding claims, characterized in that the sealing seat ( 58 ) for the control sleeve ( 59 ) on a seat plate ( 50 ; 85 ) is provided, through which the guide pin ( 48 ). Fuel injection valve device according to claim 3, characterized in that the seat plate ( 50 ; 85 ) in one piece with a housing body ( 1 ) of the fuel injection valve device is executed. Fuel injection valve device according to claim 3 or 4, characterized in that the flow channel ( 41 ; 78 ) at the discharge channel mouth into an annular space ( 44 ; 79 ), which between the seat plate ( 50 ; 85 ) and the control valve body ( 46 ; 74 ) is trained. Fuel injection valve device according to claim 5, characterized in that an inlet channel ( 70 ) in the annulus ( 44 ) opens. Fuel injection valve device according to one of claims 3 to 6, characterized in that the guide pin ( 48 ) in the region of the seat plate ( 50 ; 85 ) as multiple flat ( 55 ) is executed. Fuel injection valve device according to one of claims 3 to 7, characterized in that the seat plate ( 50 ) together with the control valve body ( 46 ) with the aid of a clamping nut ( 51 ) with the injector body ( 1 ) is tightened or screwed. Fuel injection valve device according to one of claims 1 to 8, characterized in that on the control sleeve ( 59 ) radially inside a circumferential sealing edge or a sealing lip ( 68 ) provided on the seat plate ( 50 ) comes to the plant. Fuel injection valve device according to one of claims 1 to 8, characterized in that the control sleeve ( 59 ) has a face plate facing the seat plate, which at an angle ( 66 ) to the seat plate ( 50 ) is arranged.