Information
-
Patent Grant
-
6491026
-
Patent Number
6,491,026
-
Date Filed
Friday, November 17, 200023 years ago
-
Date Issued
Tuesday, December 10, 200221 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 123 456
- 123 470
- 123 469
- 123 468
- 123 509
- 123 467
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International Classifications
-
Abstract
A fuel injection device for an internal combustion engine has a fuel distributor, which has a plurality of connecting pieces for accommodating, in a liquid-tight manner, fuel injectors. First connecting elements are provided on each connecting piece, and second connecting elements are provided on each fuel injector to achieve a secure connection. The first connecting elements on the connecting piece protrude radially inward. The second connecting elements on the fuel injector is designed as a groove-like depression. The connecting piece has a slot-like interruption in its end section having the first connecting elements.
Description
FIELD OF THE INVENTION
The present invention relates to a fuel injection device according to the definition of the species of the main claim.
BACKGROUND OF THE INVENTION
Fuel injection devices having a fuel distributor on which a plurality of connection pieces are provided for mounting fuel injectors are known from a series of documents. In general, additional connecting elements are used for secure and possibly rotation-free installation of the fuel injectors in the connection pieces; these connecting elements function as clamps or clasps in the connection area. Such connecting elements include a U-shaped elastic clamp described in German Published Patent Application No. 34 28 597, a C-shaped plastic clip described in German Published Patent Application No. 39 04 479, a U-shaped elastic clamp described in German Published Patent Application No. 39 18 410, another U-shaped elastic clamp described in German Published Patent Application No. 40 17 875, a two-legged locking plastic clip described in German Published Patent Application No. 44 13 914, a U-shaped bracket described in U.S. Pat. No. 4,823,754, and a U-shaped elastic clamp described in U.S. Pat. No. 5,035,224. All the above-mentioned fuel injection devices are characterized by the fact that the connecting element engages in a depression of the fuel injector and the connecting element engages a catching element extending radially outward in some form on the connection piece of the fuel distributor.
Furthermore, fuel injection devices in which no additional connecting elements are used in the connection area of the fuel injector and the connecting piece of the fuel distributor are known, with either catch springs (German Patent No. 39 19 231) or catch lugs (German Published Patent Application No. 195 46 441) being provided on the peripheries of the fuel injectors for such fuel injection devices. The snap springs engage a lock collar extending radially outward on the connecting piece of the fuel distributor, while the catch lugs engage in the window-like recesses of the extended connecting piece.
SUMMARY OF THE INVENTION
The fuel injection device according to present invention has the advantage that it allows the fuel injectors to be firmly and securely connected in the connecting pieces of the fuel distributors. No additional clamp or latch-type connecting elements are needed to fasten the fuel injectors. In this manner, very simple assembly and disassembly are guaranteed.
In a particularly advantageous manner, the fuel injector can be prevented from rotating using very simple measures in designing the corresponding connecting elements of the connecting piece and the fuel injector. In addition, the desired unique position of the installed injector can be achieved in a very simple manner. For this purpose, only two connecting elements of the connecting piece is designed to have different sizes, for example, which then engage in two corresponding connecting elements of the fuel injector having different sizes.
The fuel injection device is advantageously designed so that the connecting piece presses its connecting elements radially into the corresponding recessed connecting elements under radial stress due to interruptions in the end section of the connecting piece.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
shows a section of a fuel injection device.
FIG. 2
shows a first embodiment of a connecting piece as a section along line II—II in FIG.
1
.
FIG. 3
shows a second embodiment of a connecting piece as a section along line III—III in FIG.
1
.
FIG. 4
shows a third embodiment of a connecting piece as a section along line IV—IV in FIG.
1
.
FIG. 5
shows a schematic and partially sectioned side view of the connecting piece.
Embodiments of the present invention are illustrated in the drawing in a simplified manner and explained in detail in the following description.
FIG. 1
shows a section of a fuel injection device;
FIG. 2
shows a first embodiment of a connecting piece as a section along line II—II in
FIG. 1
;
FIG. 3
shows a second embodiment of a connecting piece as a section along line III—III in
FIG. 1
;
FIG. 4
shows a third embodiment of a connecting piece as a section along line IV—IV in
FIG. 1
, and
FIG. 5
shows a schematic and partially sectioned side view of the connecting piece.
DETAILED DESCRIPTION
The fuel injection device for internal combustion engines partially illustrated in
FIG. 1
has a fuel distributor
10
made of plastic or aluminum, which carries a plurality of connecting pieces
11
. The same number of fuel injectors
12
as connecting pieces
11
are provided, fuel injectors
12
protruding with their inlet-side upper ends into fuel supply openings
13
of connecting pieces
11
. Fuel injectors
12
are therefore designed as top feed injectors.
The number of connecting pieces
11
and fuel injectors
12
depends on the number of cylinders of the internal combustion engine to be supplied with fuel. For example, for a four-cylinder internal combustion engine, four fuel injectors
12
are provided, each installed in a fuel-tight manner in one of four connecting pieces
11
of fuel distributor
10
with the help of a top gasket
14
.
Fuel injector
12
protrudes with its injection-side end into a mounting hole
16
of a cylinder head
17
(direct injection) or of a mounting connection piece
17
formed on an intake manifold (intake manifold injection). Fuel-tight installation of fuel injector
12
is guaranteed by a bottom gasket
18
.
Fuel injectors
12
used in the fuel injection device according to the present invention are, for example, electromagnetically actuated injectors or injectors actuated by piezoelectric actuators or magnetostrictive actuators.
Fuel supply opening
13
of connecting piece
11
has a stepped design, for example, supply opening
13
having a smaller diameter near a distributor opening
20
of fuel distributor
10
than in an area
21
of connecting piece
11
surrounding fuel injector
12
. The outer diameter of connecting piece
11
is constant over its entire length. In order to secure fuel injector
12
in fuel supply opening
13
of connecting piece
11
, fuel injector
12
and connecting piece
11
are provided with connecting elements
22
,
23
corresponding to one another.
At least one hook-shaped connecting elements
22
is formed at the end of connecting piece
11
remote from distributor opening
20
. This at least one connecting elements
22
engages into a corresponding connecting elements
23
representing a depression on the outer periphery of fuel injector
12
. This depressed connecting elements
23
is a peripheral groove in the plastic coating of fuel injector
12
, for example. Contrary to all known devices, connecting elements
22
of the fuel injection device according to the present invention formed on connecting piece
11
protrude radially inward into fuel supply opening
13
.
FIG. 2
shows a first embodiment of a connecting piece
11
as a section along line II—II in
FIG. 1
, while
FIG. 3
shows a second and
FIG. 4
shows a third embodiment of a connecting piece
11
as a section along line III—III and line IV—IV, respectively, in FIG.
1
. The sectional drawings are only sectioned connecting pieces
11
without fuel injectors
12
that can be inserted into them.
FIGS. 2 and 3
show two examples of a two-part connecting elements
22
a,
22
b.
Two connecting elements
22
a,
22
b
diametrically opposite one another having hook-shaped cross-sections and extending approximately 80° (
FIG. 2
) in the peripheral direction are provided. Connecting elements
22
a,
22
b
may, however, also extend in an angular range of 20° to 120°. When using such a connecting piece
11
, the corresponding connecting elements
23
of fuel injector
12
can also be made of two parts. Thus, connecting elements
22
a,
22
b
may engage into two groove-like or slot-like, however not peripheral, connecting elements
23
on fuel injector
12
. This design effectively prevents fuel injector
12
from rotating.
The two connecting elements
22
a,
22
b
do not need to have the same dimensions. If connecting elements
22
a,
22
b
and the corresponding connecting elements
23
have different dimensions, as shown in
FIG. 3
, a unique installed position of fuel injector
12
in connecting piece
11
is obtained as is often desired. In this manner it is ensured, without any additional design, that the desired installed position is exactly implemented.
Connecting elements
22
may also have more than two parts; three to eight connecting elements
22
a,
22
b
may also be used. On the other hand, connecting elements
22
′ can also be made of a single piece, as
FIG. 4
shows. Connecting elements
22
′ does not extend 360° in the peripheral direction, but instead, for example, over an angular range of 240° to 320°.
As connecting elements
22
,
22
′ are interrupted at least at one point, i.e., may not extend over 360°,in order to install fuel injector
12
in connecting piece
11
, the latter is not be designed to extend over 360° at least in the area of connecting elements
22
,
22
′. Instead, connecting piece
11
in its end section
25
facing away from fuel distributor
10
and facing connecting elements
22
,
22
′ must be provided with at least one interruption
26
which allows connecting piece
11
to slightly expand radially.
FIGS. 2 and 3
show connecting pieces
11
having two interruptions
26
exactly diametrically opposite one another. In this manner, two segments of end section
25
are obtained having connecting elements
22
arranged in the middle. End section
25
may, however, be also designed with three to eight interruptions
26
, resulting in three to eight segments of end section
25
having in turn three to eight connecting elements
22
. In contrast,
FIG. 4
shows an example of connecting elements
11
having only one interruption
26
.
Interruptions
26
have a slot-shaped design, for example, the axial length of interruptions
26
being limited. Ideally, interruptions
26
have the length only sufficient so that they begin, when fuel injector
12
is mounted in connecting piece
11
, downstream from upper gasket
14
and extend up to connecting elements
22
,
22
′. Interruptions
26
are therefore applied only directly in lower end section
25
of connecting piece
11
, thus guaranteeing complete sealing by upper gasket
14
.
FIG. 5
shows this embodiment through a schematic and partially sectioned side view of connecting piece
11
. Internal fuel supply opening
13
in area
21
, i.e., upper gasket
14
, has diameter from which the at least one connecting elements
22
,
22
′ protrudes further inward in the direction toward a longitudinal injector axis
28
, so that connecting elements
22
,
22
′ engage indirectly in gasket
14
from below over a certain axial distance.
Claims
- 1. A fuel injection device for an internal combustion engine, comprising:a fuel distributor including a plurality of connecting pieces for accommodating, in a liquid-tight manner, a plurality of fuel injectors; at least one first connecting element arranged on each one of the plurality of connecting pieces, wherein: on at least one of the plurality of connecting pieces, the at least one first connecting element protrudes radially inward, and the plurality of connecting pieces each include at least one interruption in an end section that includes the at least one first connecting element; and at least one second connecting element arranged on each one of the plurality of fuel injectors, the at least one first connecting element and the at least one second connecting element corresponding to one another to achieve a secure connection, wherein: on at least one of the plurality of fuel injectors, the at least one second connecting element is shaped as a depression.
- 2. The fuel injection device according to claim 1, wherein:the at least one first connecting element has a shape of a catch hook.
- 3. The fuel injection device according to claim 1, wherein:the at least one first connecting element includes a first part and a second part.
- 4. The fuel injection device according to claim 3, wherein:the first part and the second part extend in a peripheral direction over an angular range of between 20° and 120°.
- 5. The fuel injection device according to claim 3, wherein:the first part and the second part have one of the same peripheral dimension and different peripheral dimensions.
- 6. The fuel injection device according to claim 1, wherein:three to eight of the at least one first connecting element are formed on at least one of the plurality of connecting pieces.
- 7. The fuel injection device according to claim 1, wherein:only one of the at least one first connecting element, extending over an angular range of between 240° and 320° in a peripheral direction, is provided on at least one of the plurality of connecting pieces.
- 8. The fuel injection device according to claim 1, wherein:the at least one interruption includes a number of interruptions in at least one of the plurality of connecting pieces that is equal to a number of the at least one first connecting element on the plurality of connecting pieces.
- 9. The fuel injection device according to claim 1, wherein:the at least one interruption includes a slot-like design.
- 10. The fuel injection device according to claim 1, wherein:each fuel injector protrudes with an inlet end thereof into an internal fuel supply opening of a corresponding one of each of the plurality of connecting pieces, each fuel injector includes an upper gasket used for sealing the internal fuel supply opening against the corresponding one of each of the plurality of connecting pieces, and the at least one interruption only runs downstream from the upper gasket.
- 11. The fuel injection device according to claim 1, wherein:each fuel injector protrudes with an inlet end thereof into an internal fuel supply opening of a corresponding one of each of the plurality of connecting pieces, each fuel injector includes an upper gasket used for sealing the internal fuel supply opening against the corresponding one of each of the plurality of connecting pieces, and the internal fuel supply opening and the upper gasket have a diameter from which the at least one first connecting element protrudes further inward in a direction of a longitudinal injector axis.
- 12. The fuel injection device according to claim 1, wherein:the at least one second connecting element has a shape of a peripheral groove.
- 13. The fuel injection device according to claim 1, wherein:a number of the at least one first connecting element on the plurality of connecting pieces is equal to a number of the at least one second connecting element on the plurality of fuel injectors.
Priority Claims (1)
Number |
Date |
Country |
Kind |
199 02 186 |
Jan 1999 |
DE |
|
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/DE99/03450 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO00/43668 |
7/27/2000 |
WO |
A |
US Referenced Citations (12)
Foreign Referenced Citations (7)
Number |
Date |
Country |
34 28 597 |
Feb 1986 |
DE |
39 04 479 |
Aug 1990 |
DE |
39 18 410 |
Dec 1990 |
DE |
39 19 231 |
Dec 1990 |
DE |
40 17 875 |
Dec 1991 |
DE |
44 13 914 |
Oct 1995 |
DE |
195 46 441 |
Jun 1997 |
DE |