EP1797315A2

EP1797315A2 - Retainer for a fuel injection device, and fuel injection device

Info

Publication number: EP1797315A2
Application number: EP05794675A
Authority: EP
Inventors: Thomas Fuerst; Thilo Bolz
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2004-10-01
Filing date: 2005-09-20
Publication date: 2007-06-20
Anticipated expiration: 2025-09-20
Also published as: DE102004048401A1; JP4532559B2; DE502005004836D1; DE502005007594D1; JP5032610B2; JP2010112385A; EP1953381B1; US20090056674A1; EP1953381A1; JP5032609B2; EP1906005B1; EP1906005A1; WO2006037726A3; US7802559B2; JP2010112384A; EP1797315B1; WO2006037726A2; JP2008514861A

Abstract

Disclosed is a retainer for a fuel injection device, which is characterized by a particularly simple design that allows the fuel injection valve (1) to be held down very effectively. Said fuel injection device comprises at least one fuel injection valve (1), a locating bore for the fuel injection valve (1), and a connecting branch (6) of a fuel distribution pipe (4). The retainer (10) is braced between a shoulder (12) of the fuel injection valve (1) and a final area (14) of the connecting branch (6). The inventive retainer (10) is provided with a partly annular basic element (11) from which an axially resilient retaining clip (13) extends in a curved manner. The retaining clip (13) is equipped with at least two webs (21), two inclined sections (22), and two support sections (23). The fuel injection valve (1) is particularly suitable for use in fuel injection systems of mixture-compressing spark-ignited internal combustion engines.

Description

Downholder for a fuel injection device and

Fuel injection device

State of the art

The invention is based on a hold-down for a

Fuel injection device according to the preamble of claim 1 and of a fuel injection device according to the preamble of claim 14.

It is already known from DE 29 26 490 Al a fastening device for a

Fuel injection valve for attachment to a suction pipe, in which the axial fixation of the fuel injection valve on the fuel distributor line or on a plug-in nipple by a fastener which is designed as a U-shaped securing clip, which is provided with two resiliently resilient legs. The

Securing bracket engages in the assembled state by corresponding recesses of the plug-in nipple and can be latched into a recess formed as an annular groove in a connecting piece of the fuel injection valve. The axial clearance between the recesses and the securing clip as well as between the annular groove and the securing clip should be kept small in order to achieve an exact fixation of the fuel injection valve without tension of the seal.

A disadvantage of the known from DE 29 26 490 Al fastening device is in particular the bracing effect of the various support parts the fuel injector. The force flow generated in the fuel injection valve leads to deformations and thus to changes in the stroke of the valve needle to jamming and to a pressure or bending load of the housing parts, which are generally thin-walled and welded together at several points. In addition, each attachment measure, for example, by a

Support collar to increase the radial extent of the fuel injection valve and thus to an increased space requirement during installation.

Already known from DE 101 08 193 Al a fastening device for the mutual attachment of a fuel injection valve in one

Cylinder head of an internal combustion engine and the fuel injection valve to a fuel rail. The fastening device comprises a sleeve which is clamped between a shoulder of the fuel rail and a shoulder of the fuel injection valve and is formed of an elastic material. The sleeve can due to their tubular structure the

Holddown forces only partially effectively transferred to the fuel injector. The claimed by the shoulders of the fuel injector and fuel rail surfaces of serving as hold down sleeve represent the manufacturing edges resulting in the production of the blank of the sleeve cutting edges.

Advantages of the invention

The hold-down device according to the invention for a fuel injection device with the characterizing features of claim 1 has the advantage that it has a particularly simple design, is very simple and inexpensive to produce and still a very effective holddown of a

Fuel injection valve in a receiving bore of a cylinder head or an intake pipe is achieved. With conventional manufacturing processes, such as punching, EDM or laser cutting blanks can be removed from sheets of spring steel or stainless steel for the subsequent hold-down and by

Bend into numerous, quite complex desired shapes. With the hold-down device according to the invention without means for Verdrehfixierung a more accurate alignment of the fuel injector over known holddowns with integrated Verdrehfixierungen is possible, since the component tolerances of the holddown for Verdrehfixierung entiallen by the inventive design. The hold-down device can also compensate for larger axial tolerances than is possible with known hold-downs. Above all, in conjunction with the fuel injection device specified in claim 14, which has a simple Verdrehfixierung, the above-mentioned advantages.

The measures listed in the dependent claims advantageous refinements and improvements of the claim 1 hold-down are possible.

It is advantageous to carry out the hold-down as a stamped and bent part and shape and obstruct in a fuel injector that the stress of bending stress surfaces of the inclined portions and abutment portions of the blank perpendicular to the cutting edges, the release of the blank for the Hold-downs from the corresponding sheet arise. In this way, the permanent load capacity of the

Increase bending stressed portions of the hold-down bracket of the hold-down and achieve an optimal hold-down force on the fuel injection valve for secure fixation in the receiving bore.

The fuel injection device according to the invention with the characterizing

Features of claim 14 has the advantage that a direct and thus very accurate Verdrehfixierung between fuel injector and connecting piece is created by simple measures on the fuel injector and the connection piece. For this purpose, a pin-shaped raised pin is provided on the fuel injection valve, which corresponds to a groove-like recess or recess on the connection piece of the fuel distribution line. The protruding into the recess pin of the fuel injection valve ensures regardless of the hold-down for a rotation of the fuel injection valve over the Fuel distribution line and for a reliable assignment of the rotational position of the blank holder to the fuel injection valve.

The measures listed in the dependent claims advantageous refinements and improvements of claim 14 are given

Fuel injection device possible.

It is particularly advantageous to provide the hold-down in the circumferential direction with an open area in such a way that it is penetrated by the connection plug of the fuel injection valve, so that a clear installation position is defined for the hold-down. A Verdrehfixierung the blank holder relative to the connection piece is eliminated by the mating pin / recess on the fuel injector / nozzle. The hold-down is mounted on the fuel injector in such a way that a hold-down clamp, which is subject to bending stress, comes from the connector of the

Fuel injector is directed away.

drawing

Ausiührungsbeispiele of the invention are shown in simplified form in the drawing and explained in more detail in the following description. FIG. 2 is a perspective view of the fuel injection device according to FIG. 1, FIG. 3 is a perspective view of a second embodiment of a fuel injection device, FIG 3 used hold-down as a single component, Figure 5 shows a second embodiment of a hold-down invention and Figure 6 shows a third embodiment of a hold-down invention.

Description of the embodiments

In Fig. 1, as an embodiment, a valve in the form of an injection valve 1 for fuel injection systems of mixture compressing spark-ignition internal combustion engines shown in a side view. The fuel injection valve 1 is part of a fuel injection device. With a downstream end, the fuel injection valve 1, which is designed in the form of a direct-injection injector for injecting fuel directly into a combustion chamber of the internal combustion engine, into a

Built-in bore of a cylinder head, not shown installed. A sealing ring 2, in particular of Teflon®, ensures optimum sealing of the fuel injection valve 1 with respect to the wall of the cylinder head. The valve receptacle can also be provided on a receiving neck of a suction pipe, not shown.

The fuel injection valve 1 has at its inlet-side end 3 a plug connection to a fuel distributor line 4, which is represented by a sealing ring 5 between a connecting piece 6 of the fuel distributor line 4, which is shown in section, and an inlet connection 7 of

Fuel injection valve 1 is sealed. The fuel injection valve 1 has an electrical connection plug 8 for the electrical contacting for actuating the fuel injection valve 1.

In order to space the fuel injection valve 1 and the fuel distributor line 4 radially from one another and to hold down the fuel injection valve 1 securely in the receiving bore of the cylinder head or intake pipe, a hold-down device 10 is provided according to the invention between the fuel injection valve 1 and the connecting piece 6. The hold-down 10 is designed as a bow-shaped component, e.g. as a punching bend

Part. The hold-down 10 has a part-ring-shaped base element 11, wherein this base element 11, which does not rotate through 360 °, but e.g. only an extension of about 250 ° to 320 °, is supported on a shoulder 12 of the fuel injection valve 1. With a bent from the flat base member 11, axially resilient hold-down 13 is the

Hold-down 10 at a downstream end surface 14 of the connecting piece 6 to the fuel rail 4 in the installed state. In the area of the electrical connector 8, the hold-down 10 is interrupted, the hold-down 10 forms a closed bracket element, in particular Figures 2 to 4 illustrate. In this way, the hold-down 10 can surround the fuel injector 1 and still allows the passage of the electrical connector plug 8. The hold-down bar 13 protrudes with its resilient brackets from the connector 8 away.

In the transition region of the electrical connector 8 to the fuel injection valve 1 at least partially in the region of the inlet nozzle 7 enveloping Kunststoffumspritzung a pin-shaped raised pin 15 is provided on the fuel injector 1, with a groove-like recess or recess 16 on the connecting piece 6 of

Fuel distribution line 4 corresponds. The protruding into the recess 16 pin 15 of the fuel injector 1 provides a direct and thus very secure rotation of the fuel injector 1 relative to the fuel rail 4 and for a reliable assignment of the rotational position of the blank holder 10 to the fuel injector 1. On the other hand, with the downholder 10 according to the invention a more accurate Alignment of the fuel injection valve 1 compared to known downholders with integrated Verdrehfixierungen possible because the component tolerances of the blank holder 10 entiallen for Verdrehfixierung by the inventive design. The hold-down 10 can also compensate for larger axial tolerances, as is possible with known holders.

The recess 16 on the connecting piece 6 of the fuel distributor line 4 extends from the end face 14 and extends in slot-like or groove-like manner in the axial direction. The recess 16, e.g. introduced by machining, it has such an axial extent that the pin 15 of the fuel injection valve 1 can be taken in full length. FIG. 2 shows the fuel injection device according to FIG. 1 in a perspective view. Particularly clarified by this illustration, the mounting position of the blank holder 10 between the shoulder 12 and the

End surface 14 and the engagement of the pin 15 in the recess 16th

The second exemplary embodiment of a fuel injection device shown in a perspective illustration in FIG. 3 differs from FIG The connection piece 6 of the fuel distribution line 4 has at its downstream end an annular projecting collar 19, on which the end face 14 for conditioning the blank holder 10 with his Hold-down bracket 13 is formed and in which the recess 16 is formed. The groove-like recess 16 is in the installed state of the

Fuel injection valve 1 completely penetrated by the pin 15. In the e.g. deep-drawn connection piece 6, the recess 16 is introduced by means of punching or by machining.

FIGS. 4 to 6 show three embodiments of hold-downs 10 according to the invention, wherein the hold-down 10 shown in FIG. 4 as a single component corresponds to the hold-downs 10 used in the fuel injection devices of FIGS. 1 to 3. All embodiments are characterized in that, starting from a planar part-ring-shaped base element 11, at least one bent, axially resilient hold-down bracket 13 extends out of the plane of the base element 11.

The base member 11 is formed spangenförmig and surrounds the

As already described, the connection plug 8 of the fuel injection valve 1 extends through the open area 20 of the base element 11 of the hold-down 10. The base element 11 can largely circular (Figures 4 and 5) or in dependence of the shape of the fuel injection valve 1 also eg Pear-shaped (Figure 6) or similar in cross-section. In the example shown in Figure 4, the base 11 is flat, e.g. made with a thickness of about 1.5 mm, so that there is a large contact surface on the shoulder 12. In contrast, the basic elements 11 of the downholders 10 of Figures 5 and 6 are edgewise, e.g. again with a wall thickness of approx.

1.5 mm, but thus also dictates the small width of the support surface of the respective base member 11 on the shoulder 12. The hold-down device 10 according to FIG. 4 represents a closed stirrup element, since the hold-down stirrup 13 is connected endlessly to the base element 11. From the base member 11, two webs 21 extend with increased width largely in the axial direction and thus substantially perpendicular to the extension plane of the base member 11. These webs 21 go kinked into the actual axially resilient holddown 13, wherein the hold-down bracket 13 composed of three essential sections. The hold-down bar 13 has, starting from the webs 21, only a small axial extent, which results from two uniform oblique sections 22. The oblique sections 22 merge into slightly curved contact sections 23 which, in the installed state, ultimately have touching contact with the end face 14 of the connecting piece 6. Between the abutment portions 23, a connecting portion 24 is provided, which is carried out slightly lowered relative to the abutment portions 23 and ensures that the entire hold-down device 10 is closed. The circumferential extent of the hold-down strap 13 with its sections 22, 23 and 24 corresponds largely to that of the base element 11, but in a different axial plane, caused by the height of the webs 21st

In contrast to the hold-down 10 described above, the hold-down

10 according to Figures 5 and 6, no connecting portion 24, so that an overall open down device 10 is present. From the base element 11 in turn two webs 21 extend substantially in the axial direction and thus substantially perpendicular to the plane of extension of the base member 11. The webs 21 are twisted with respect to their wall thickness relative to the base member 11, wherein the transition region 25 inwardly (Figure 6) or outside (Figure 5) can be turned. As Figure 6 shows, the webs 21 may have a curved, for example S-shaped configuration. The webs 21 go over bent into the actual axially resilient hold-down bar 13, wherein the hold-down bar 13 composed of two sections. The hold-down bar 13, starting from the webs 21 only a small axial extent, resulting in two uniform oblique sections 22. The oblique sections 22 merge into slightly curved contact sections 23, which ultimately come into contact with the end face 14 of the contact-making contact in the installed state Have connecting piece 6. The two abutment sections 23 of each hold-down 10 terminate the two-part hold-down bar 13 in this way.

The entire hold-down bar 13 with its inclined sections 22 and abutment sections 23 and the connecting section 24 in turn has a

Wall thickness of about 1.5 mm, while the width of the hold-down bracket 13, in particular the abutment portions 23 is greater.

All described downholders 10 are used e.g. separated by punching, eroding or laser cutting from sheets of spring steel or stainless steel (with a thickness of about 1.5 mm) and then brought by bending in the desired shape. All embodiments of the blank holder 10 according to the invention have in common that the stressed by bending stress surfaces of the blank holder 10, in particular the inclined portions 22 and the abutment portions 23 perpendicular to the cut edges 27, which in the dissolution of the

Blanks are defined for the hold-10 from the corresponding sheet.

The individual features of the hold-down device 10 shown in FIGS. 4 to 6 can also lead to different hold-down devices 10 according to the invention in various combinations (not shown).

Claims

claims

1. hold-down iür a fuel injection device comprising at least one fuel injection valve (1), a receiving bore for the fuel injection valve (1) and a connecting piece (6) of a fuel distributor line (4), wherein the hold-down (10) between a

Shoulder (12) of the fuel injection valve (1) and an end face (14) of the connecting piece (6) is clamped, characterized in that the hold-down (10) has a part-annular base member (11), bent from which an axially compliant Niederhaltebügel ( 13), the at least two webs (21), two inclined sections (22) and two

Has investment sections (23).

2. Down device according to claim 1, characterized in that the base element (11) of the hold-down (10) on the shoulder (12) of the fuel injection valve (1) can be placed.

3. hold-down according to claim 1 or 2, characterized in that the contact portions (23) of the hold-down bracket (13) to the end face (14) of the connecting piece (6) can be applied.

4. hold-down according to one of the preceding claims, characterized in that the bending stress-loaded surfaces of the inclined sections (22) and contact sections (23) perpendicular to the cut edges (27) extending during the extraction of the blank for the hold-down (10) from the corresponding sheet arise.

5. Down device according to one of the preceding claims, characterized in that it is designed as a stamped and bent part.

6. Down device according to one of the preceding claims, characterized in that the sheet used for the hold-down (10) consists of spring steel or stainless steel.

7. hold-down according to claim 4 or 6, characterized in that the holding-down device (10) has a wall thickness of about 1.5 mm corresponding to the sheet thickness used.

8. Down device according to one of the preceding claims, characterized in that the base element (11) is designed as a flat part ring according to the sheet thickness used.

9. down device according to one of claims 1 to 7, characterized in that the base element (11) is designed as upright part ring standing, whose wall thickness corresponds to the sheet thickness used.

10. Down device according to one of the preceding claims, characterized in that the two abutment portions (23) of the hold-down bracket (13) via a connecting portion (24) are directly connected to each other, so that the entire down-holder (10) forms a closed bracket element.

11. Hold-down device according to claim 10, characterized in that the circumferential extent of the hold-down strap (13) largely corresponds to that of the base element (11).

12. Down device according to one of claims 1 to 9, characterized in that the two abutment sections (23) of the hold-down bar (13) terminate this, so that the hold-down (10) is open.

13. Down device according to claim 12, characterized in that the webs (21) with respect to their wall thickness twisted relative to the base element (11) extend.

14. Fuel injection device for fuel injection systems of

Internal combustion engine having at least one fuel injection valve (1), a receiving bore for the fuel injection valve (1), a connecting piece (6) of a fuel distributor line (4) and a hold-down device (10) between a shoulder (12) of the fuel injection valve (1) and an end face (14 ) of the connecting piece (6), characterized in that regardless of

Downholder (10) on the fuel injection valve (1) a raised pin (15) is provided, which engages in a recess (16) on the connecting piece (6).

15. Fuel injection device according to claim 14, characterized in that the pin (15) in a transition region of an electric

Connection plug (8) is provided to a fuel injection valve (1) at least partially enveloping Kunststoffumspritzung.

16. Fuel injection device according to claim 14 or 15, characterized in that the recess (16) extends slit-like or groove-like manner on the connecting piece (6).

17. Fuel injection device according to one of claims 14 to 16, characterized in that the connecting piece (6) has at its downstream end an annular projecting collar (19).

18. Fuel injection device according to one of claims 14 to 17, characterized in that the hold-down device (10) has a part-ring-shaped base element (11), from which an axially compliant hold-down bracket (13) extends, which has at least two webs (21), two

Has oblique sections (22) and two abutment sections (23).

19. Fuel injection device according to claim 15, characterized in that the hold-down device (10) seen in the circumferential direction an open area (20), which is penetrated by the connector (8) of the fuel injection valve (1).

20. Fuel injection device according to claim 15 or 19, characterized in that the holding-down device (10) is mounted on the fuel injection valve (1) such that a hold-down bar (13) is directed away from the connection plug (8) of the fuel injection valve (1).