DE102004035645A1 - Fuel supply for a direct injection internal combustion engine - Google Patents

Abstract

The fuel supply (1) has a supply pipe (3) comprising a plurality of pipe sections (2). In the joint region (10) of two pipe sections (2), a branch (4) which can be secured to the motor housing is provided, in which connection channels (5, 6) are formed for transferring fuel from the supply line (3) to form an injection unit. The branch (4) forms an integral part of the pipe section (2) at a first end (6). Here, the pipe section (2) has a neck (8) drawn in the diameter, the outer diameter (AD) of which is adapted to the inner diameter (ID) of the pipe section (2) at the other second end (9). Pipe section (2) and branch (4) are made in one piece by stainless steel casting.

Description

The The invention relates to a fuel supply for an internal combustion engine with Direct injection according to the characteristics in the preamble of claim 1.

Such a fuel supply forms by the disclosure of the DE 199 53 942 C2 State of the art. It comprises a supply line, which consists of several pipe sections. Adjacent end faces of successive pipe sections are arranged at a distance from each other. These areas are overlapped by sleeve-like branches, which may consist of light metal, such as aluminum, or also of plastic. The pipe sections are made of aluminum, steel or plastic.

At each branch are end-to-end diagonally opposite one another eyelets provided, with mutually parallel through holes are provided. about these eyelets can the branches on the motor housing be determined. additionally to the two eyelets is in the middle range each branch a lateral boom provided in which a blind hole is located. This blind hole is over one Slanted bore connected to the area located within the branch between two end faces of adjacent pipe sections is located. About the Blind hole and the oblique hole is the supply line coupled to an injection unit. The oblique bore extends in a transverse plane that is offset by 90 ° to one the longitudinal axis the supply line cutting plane is arranged.

The Number of branches corresponds to the number of cylinders of the internal combustion engine. The free ends of the supply line can closed by caps, these end caps with connections, For example, with a high pressure line for the fuel or for a High pressure sensor, can be provided.

The known fuel supply is multi-part and relatively large in the branches designed as the ends of the pipe sections of the supply into the branches. It therefore requires a relatively high Production expense. Also each branch has at its ends two each other diagonally opposite lying eyelets, whereby an even larger installation volume to take into account is.

Of the Invention is - starting from the prior art - the Task is based, a fuel supply for an internal combustion engine with Direct injection, which is more compact and simpler can be produced without this, the fuel content in the supply line to lower.

These The object is achieved with the features specified in claim 1.

After that each pipe section has a diameter at a 1st end retracted neck. The outer diameter the nozzle is the inner diameter of the pipe section at the other 2. Adjusted to the end. Consequently, the nozzle grips on a pipe section in the 2nd end of another pipe section tightly, if two Pipe sections are coupled together. The front sides of the pipe sections at the 2nd end come on annular end surfaces on the circumference of the nozzle to the plant. In this way, the entire receives feed a steady, almost non-protruding outer contour. Another advantage of the invention results from the fact that now exclusively via the branch both the transfer of the under high pressure fuel to the injection unit takes place as well as the definition of the branch on the motor housing. This is the compactness while maintaining the highest possible Flow area for the Fuel further increased. The number of items is the one-piece piece of a pipe section and a branch significantly lowered. Thus, the tolerance problems are also reduces and reduces the risk of leakage.

Around to prevent the gap between them due to the pressure of the fuel a stub and a second end of a pipe section widened is is according to claim 2, the wall thickness of the nozzle is smaller than the wall thickness of the second end sized. It then appears appropriate, the overlap region of the nozzle with the 2nd end by brazing connect to. It can However, other suitable compounds are provided which the tightness in the joint area ensure two pipe sections.

The flow of the fuel from one pipe section to the next pipe section is improved according to claim 3, characterized in that the longitudinal channel in the neck over a conically widening mouth leaking into the front of the nozzle. The flow resistance due to the engaging in the second end of a pipe section neck therefore not noticeably increased.

Each pipe section is still kompak in accordance with the features of claim 4 designed that the branch is designed as a lateral connection console, in which both the connecting channels and a fixing hole for attachment of the branch to the motor housing are formed.

To Claim 5, the connecting channels of a blind hole in Branch and one of the blind bore with the longitudinal channel in the nozzle connecting oblique bore educated. Here is one the axis of the blind bore intersecting transverse plane immediately adjacent the neck. The oblique hole extends from the blind bore through an inclined transition section between the branch and the neck. This also gives the branch an even more compact design. The axis of the oblique hole extends both to the axis of the blind bore and to the axis of the longitudinal channel in the pipe section or nozzle at an angle other than 90 °.

The Compactness of the branch area is further developed according to claim 6 support that the axes of the blind bore and the fixing hole in one Plane extending parallel to one through the axis of the pipe section extending level is arranged.

In order to the oblique hole between the longitudinal channel in the nozzle and the blind hole in the branch perfectly and easily can be produced, provide the features of claim 7, that the axis of the tangential bore in the blind bore oblique bore the estuary of the neck cuts.

in the In view of the facts that the production of the oblique bore appropriate by drilling done, runs according to claim 8, the oblique bore in one in the longitudinal channel of the neck projecting projection whose front is vertical to the axis of the oblique bore extends and the mouth facing the neck. In this way, there are no difficulties when applying a drill for producing the oblique bore. Also, the flow conditions at the crossing of the fuel in the oblique bore improved.

A another embodiment of the branch area is seen in the features of claim 9. After that are the connection channels from a blind hole in the branch and from a blind hole with one to the longitudinal channel connecting in the pipe section open internal chamber of the branch oblique bore educated. Through the inner chamber is the receiving volume for fuel in the supply line elevated.

Corresponding Claim 10 is the axis of the oblique bore between the blind bore and the mouth aligned with the pipe section at the 2nd end. In this embodiment extends the flow direction in the supply line preferably from the second end of a pipe section in the direction of the nozzle on 1st end.

It proves to be further according to the invention advantageous if according to claim 11 the mouths the blind bore and the fixing hole opposite surface of the Branches approximately in a plane, which also through the Axle of the pipe section extends.

Around unnecessary material accumulations to avoid is in accordance with claim 12 provided that the fixing hole in a sleeve-like extension the branch continued is.

Of Furthermore, it constitutes an essential feature of the invention that according to claim 13 of the pipe section and the one piece connected, designed as a connection console designed branch made of cast stainless steel are. When stainless steel casting can very accurate tolerances are met. Also, it is possible here, the embodiment a pipe section with an inner chamber in the branch by a produce lost core. With this lost core can at the same time also the oblique hole be formed between the blind bore and the inner chamber.

The Anti-rotation device according to claim 14, in particular in the form of a molded projection in the area between the blind bore and the fixing hole, acts with a Recess on the injection unit (injector) together to the injector to hold in his position. Ensures the rotation, that - in particular SGDI (Spray Guided Direct Injection) - the spray pattern of the injector is at a fixed angle to a spark plug.

The Invention is illustrated below with reference to the drawings embodiments explained in more detail. It demonstrate:

1 in a horizontal longitudinal section a portion of a supply line for fuel to an injection unit of a direct injection internal combustion engine;

2 an end view on the representation of 1 , seen in the direction of arrow II;

3 a side view of the representation of 1 , seen in the direction of arrow III and

4 a representation similar to the 1 according to a further embodiment.

With 1 is in the 1 a longitudinal section of a fuel supply for an otherwise not shown internal combustion engine with direct injection.

The fuel supply 1 has a multiple pipe sections 2 comprehensive supply line 3 on ( 1 to 3 ). This is traversed by the fuel in the direction of the arrow STR. Every pipe section 2 is a fixable on the housing of the internal combustion engine branch 4 in the form of a connection console assigned in one piece. pipe section 2 and branch 4 are made of cast stainless steel. In the branch 4 are connection channels 5 . 6 for transferring fuel from the supply line 3 provided to an injection unit. The number of branches 4 on the pipe sections 2 corresponds to the number of cylinders of the internal combustion engine.

Every pipe section 2 indicates a 1st end 7 a diameter drawn neck 8th on. Its outer diameter AD is the inner diameter ID of the pipe section 2 at the other 2nd end 9 customized. In this way, two pipe sections 2 in the joint area 10 be plugged directly axially tight. Here then summarizes the 2nd end 9 a pipe section 2 over the neck 8th at the 1st end 7 of the following pipe section 2 , The front side 11 of the 2nd end 9 of the pipe section 2 comes on an annular end surface 12 circumference of the neck 8th to the plant.

The wall thickness WD of the neck 8th is smaller than the wall thickness WD1 at the 2nd end 9 of the pipe section 2 sized.

The longitudinal channel 13 in the neck 8th runs over a conically expanding mouth 14 in the front side 15 of the neck 8th out.

The connection channels 5 . 6 are from a blind hole 5 in the branch 4 and from one the blind hole 5 with the longitudinal channel 13 in the neck 8th connecting oblique hole 6 educated. This is where the axis cuts 16 the tangential in the blind hole 5 incoming inclined bore 6 the estuary 14 of the neck 8th , The axis 16 the oblique hole 6 runs both to the axis 17 the blind hole 5 as well as to the axis 18 of the pipe section 2 at an angle other than 90 °.

The oblique hole 6 runs in one in the longitudinal channel 13 of the neck 8th protruding projection 19 out. Its front page 20 extends perpendicular to the axis 16 the oblique hole 6 and is the mouth 14 of the neck 8th facing.

In the branch 4 is a fixing hole 22 introduced, whose axis 21 parallel to the axis 17 the blind hole 5 runs.

The axes 17 . 21 the blind hole 5 and the fixing hole 22 extend in a common plane EE parallel to one through the axis 18 of the pipe section 2 extending plane E ₁ -E _{1 is} arranged.

The mouths 23 . 24 the blind hole 5 and the fixing hole 22 opposite surface 25 of the branch 4 runs approximately in a plane E ₂ -E ₂ , which also extends through the axis 18 of the pipe section 2 extends.

The fixing hole 22 is in a sleeve-like extension 26 of the branch 4 continued.

In the 4 is an embodiment of a pipe section 2a represented, from the principle of the embodiment of the 1 to 3 equivalent. That means, two pipe sections each 2a can over a spigot 8th at the 1st end 7 and the 2nd end 9 be tightly plugged together. Also is with the pipe section 2a a branch 4a connected in the form of an integrally attached terminal console. pipe section 2a and branch 4a are made by stainless steel casting.

The connection channels 5 . 6a consist in this embodiment of a blind hole 5 in the branch 4a and from one the blind hole 5 with one to the longitudinal channel 27 in the pipe section 2a towards open inner chamber 28 of the branch 4a connecting oblique hole 6a , The axis 29 the oblique hole 6a is between the blind hole 5 and the mouth 30 of the pipe section 2a at the 2nd end 9 aligned. The flow direction in this case runs according to the arrow STR1.

Both in the design of the 1 to 3 as well as those of 4 is at the junction 4 . 4a in the area between the blind hole 5 and the fixing hole 22 an anti-twist device 31 provided in the form of a molded-on projection. The anti-rotation device cooperates with a recess on an injection unit (injector) in order to always keep it in its position. In this way it can be ensured that - especially in the case of SGDI (Spray Guided Direct Injection) - the spray pattern of the injector is at a fixed angle to a spark plug.

1

Fuel supply

2

pipe sections

2a

pipe section

3

feed

4

junction

4a

junction

5

blind hole

6

oblique bore

6a

oblique bore

7

1st end of v. 2

8th

Neck on 7

9

2nd end of v. 2

10

Impact area v. 2

11

Front side v. 9

12

end face

13

Longitudinal channel in 8th

14

Estuary v. 8th

15

Front side v. 8th

16

Axis v. 6

17

Axis v. 5

18

Axis v. 2

19

Lead in 13

20

Front side v. 19

21

Axis v. 22

22

Fixing hole in 4 . 4a

23

Estuary v. 5

24

Estuary v. 22

25

Surface v. 4

26

Extension v. 4 . 4a

27

Longitudinal channel in 2a

28

inner chamber in 4a

29

Axis v. 6a

30

Estuary v. 9

31

twist

AD

Outside diameter v. 8th

ID

Inner diameter v. 2 . 2a

E-E

Level through 17 . 21

E ₁ -E ₁

Level through 18

STR

flow direction

STR ₁

flow direction

WD

Wall thickness v. 8th

WD ₁

Wall thickness v. 2 . 2a

Claims (14)

Fuel supply for a direct injection engine, comprising a plurality of pipe sections ( 2 . 2a ) comprehensive supply line ( 3 ), wherein in the joint area ( 10 ) of two pipe sections ( 2 . 2a ) a fixable on the motor housing branch ( 4 . 4a ), in which connection channels ( 5 . 6 ; 6a ) for transferring fuel from the supply line ( 3 ) are formed into an injection unit, characterized in that each pipe section ( 2 . 2a ) at a first end ( 7 ) a necked in diameter neck ( 8th ) whose outer diameter (AD) the inner diameter (ID) of the pipe section ( 2 . 2a ) at the other 2 nd end ( 9 ), the branch ( 4 . 4a ) an integral part of the pipe section ( 2 . 2a ) at the with the neck ( 8th ) 1. end ( 7 ). Fuel feed according to claim 1, characterized in that the wall thickness (WD) of the nozzle (WD) ( 8th ) smaller than the wall thickness (WD ₁ ) at the 2nd end ( 9 ) of the pipe section ( 2 . 2a ) is dimensioned. Fuel supply according to claim 1 or 2, characterized in that the longitudinal channel ( 13 ) in the neck ( 8th ) via a conically widening mouth ( ^ 14 ) in the front ( 15 ) of the neck ( 8th ) expires. Fuel supply according to one of claims 1 to 3, characterized in that the branch ( 4 . 4a ) in the form of a lateral connection console, in which both the connection channels ( 5 . 6 ; 6a ) as well as a fixing hole ( 22 ) are provided. Fuel supply according to claim 4, characterized in that the connecting channels ( 5 . 6 ) from a blind bore ( 5 ) in the branch ( 4 ) and from a blind hole ( 5 ) with the longitudinal channel ( 13 ) in the neck ( 8th ) connecting oblique bore ( 6 ) are formed. Fuel supply according to claim 5, characterized in that the axes ( 17 . 21 ) of the blind bore ( 5 ) and the fixing hole ( 22 ) extend in a common plane (EE) parallel to one through the axis ( 18 ) of the pipe section ( 2 . 2a ) extending plane (E ₁ -E ₁ ) is arranged. Fuel supply according to claim 5 or 6, characterized in that the axis ( 16 ) of the tangential in the blind bore ( 5 ) incoming oblique bore ( 6 ) the mouth ( 14 ) of the neck ( 8th ) cuts. Fuel supply according to one of claims 5 to 7, characterized in that the oblique bore ( 6 ) in one in the longitudinal channel ( 13 ) of the neck ( 8th ) protruding projection ( 19 ), whose front side ( 20 ) perpendicular to the axis ( 16 ) of the oblique bore ( 6 ) and the mouth ( 14 ) of the neck ( 8th ) is facing. Fuel supply according to one of claims 1 to 4, characterized in that the connecting channels ( 5 . 6a ) from a blind bore ( 5 ) in the branch ( 4a ) and from a blind hole ( 5 ) with one to the longitudinal channel ( 27 ) in the pipe section ( 2a ) open internal chamber ( 28 ) of the branch ( 4a ) connecting oblique bore ( 6a ) are formed. Fuel supply according to claim 9, since characterized in that the axis ( 29 ) of the oblique bore ( 6a ) between the blind bore ( 5 ) and the mouth ( 30 ) of the pipe section ( 2a ) on the 2nd end ( 9 ) is aligned. Fuel supply according to one of claims 5 to 10, characterized in that the mouths ( 23 . 24 ) of the blind bore ( 5 ) and the fixing hole ( 22 ) opposite surface ( 25 ) of the branch ( 4 . 4a ) runs approximately in a plane (E ₂ -E ₂ ), which also extends through the axis ( 18 ) of the pipe section ( 2 . 2a ). Fuel supply according to one of claims 4 to 11, characterized in that the fixing bore ( 22 ) in a sleeve-like extension ( 26 ) of the branch ( 4 . 4a ) is continued. Fuel supply according to one of claims 4 to 11, characterized in that the pipe section ( 2 . 2a ) and the branch ( 4 . 4a ) are made of cast stainless steel. Fuel supply according to one of claims 1 to 13, characterized in that at the branch ( 4 . 4a ) an anti-twist device ( 31 ) is provided.