Fuel injection system

A fuel injection system is proposed for internal combustion engines having a plurality of injection valves for supplying fuel to the engine. Each injection valve is connected by a yieldable support bracket with a rigid fuel distributor line. The bracket is mounted pivotally with an annular coller secured to the injection valve. The fuel distributor line is arranged to engage rib-like carrier members connected with the internal combustion engine and is held against the carrier member by yielding clamp elements. After the valves are engaged in the sockets of the fuel distributor line and the bore of the cylinder head, then the support brackets are swung upwardly to tension the seal elements that are disposed in proximity to the opposite ends of the valve. As a result, not only a more secure connection between the fuel distributor line and the injection valves is obtained, but also rapid assembly or disassembly of the fuel injection system.

BACKGROUND OF THE INVENTION 
The invention relates to a fuel injection system of the type described 
herein and finally claimed. A fuel injection system is already known in 
which the injection valves are inserted into appropriate openings in the 
intake pipes, and where the injection valves are firmly held by means of a 
fuel distributor line provided with appropriate socket elements. In this 
system, however, there is the danger that under sufficient mechanical 
stress these socket elements may loosen and the fuel may spray into the 
engine area and thereby cause a fire. A further disadvantage of this known 
fuel injection system is that all the injection valves must be inserted 
seriatim into the connection socket before the support means for the fuel 
distributor line can be tightened. 
OBJECT AND SUMMARY OF THE INVENTION 
The fuel injection system in accordance with the invention as claimed 
herein has the advantage over the prior art that beyond the increased 
security against loosening of the socket and plug connection provided for 
between the fuel distributor line and the injection valves, more rapid 
mounting is also possible, because the injection valves, which are coupled 
with the fuel distributor line via the yielding support bracket can now be 
inserted and mounted in the engine as a separately accessible element 
which can be individually examined and assembled. 
Advantageous further embodiments and improvements of the fuel injection 
system disclosed in the main claim can be attained by means of the 
features of the dependent claims. Thus, it is of particular advantage to 
embody the support bracket in the form of a loop and to support it 
pivotably on the injection valve. In this manner pressure is brought to 
bear against the injection valve and the fuel distributor line and 
ultimately the looped portion is received in a depressed area in the fuel 
distributor line. As a result, there is a secure connection provided 
between the injection valve and the fuel distributor line, and one which 
may be quickly established as well as quickly releasable. 
It is also advantageous to support the fuel distributor line in a 
form-locking manner on the carrier members that are connected to the 
internal combustion engine and to press the fuel distributor line by means 
of clamps against these carrier members, as a result of which a more 
secure supporting arrangement is established and rapid assembly and 
disassembly become possible. 
The invention will be better understood as well as further objects and 
advantages thereof become more apparent from the ensuing detailed 
description of preferred embodiments taken in conjunction with the 
drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In the fuel injection system shown in FIG. 1, intended for the operation of 
an internal combustion engine which is not shown, reference numeral 1 
indicates a fuel distributor line which is of rigid construction and made, 
for example, of metal. The fuel distributor line 1 is connected first with 
the pressure side of a fuel supply pump, not shown, and second, via a 
pressure controller, which is also not shown, with the intake side of the 
fuel supply pump or with the fuel tank. The distributor line 1 is provided 
with a plurality of openings into which sockets 2 are arranged to be 
seated and in this way fuel from the fuel distributor line 1 can flow 
through the bore 3 of each of the sockets 2. A connecting plug 4 of an 
injection valve 5 is insertable into the internal bore 3 of the socket 2, 
as shown. In this exemplary embodiment, by way of example, there is shown 
an electromagnetically actuatable injection valve 5 which is triggerable 
in a known manner by an electronic control device, not shown, in 
accordance with operating conditions of the internal combustion engine. 
One end of the injection valves 5 is guided via a guide portion 6 within a 
bore 7 of each of the sockets 2. The seal between the socket 2 and the 
injection valve 5 may be effected in a known manner by means of one or 
more elastic sealing elements 8, such as an O-ring or other sealing means. 
An annular bearing member 10, which is made of suitably rigid sheet metal, 
for instance, is supported on a flanged area remote from the connecting 
socket 4 in such a manner that it cannot be displaced in the direction of 
the connecting socket 4. The annular cup-shaped bearing member 10 is 
provided with two opposed means defining openings 11 in its upstanding 
wall which lies in a plane spaced from but parallel to the injection valve 
5. A support bracket 13 is provided with a pair of dependent leg members, 
as shown, each of which have a terminal end portion 12 that is bent at 
right angles and then inserted into the openings 11 of the annular collar 
10. It will be readily understood that the support bracket 13 is pivotably 
supported relative to the injection valve 5 by the end portions 12. The 
support bracket 13, which is embodied of spring steel wire, for instance, 
has a looped portion 15 in the upper area thereof remote from the bearing 
ends 12. In the assembled condition of the injection valve 5, as shown in 
FIGS. 1 and 2, this looped portion 15 extends at least half-way around the 
fuel distributor line 1 and its dependent protrusion or nose portion 16 
that is formed by shaping the looped portion 15 is arranged to be received 
within a detent area of the fuel distributor line 1 embodied as a groove 
17. 
In the installed condition, the injection valve 5 is therefore pressed 
under tension against the sealing element 8 by the yielding support 
bracket 13. Thus, the support bracket 13 provides an easily assemblable 
support means between the fuel distributor line 1 and each injection valve 
5. 
In FIG. 4, by way of example, four injection valves 5 are shown, which are 
secured to the fuel distributor line 1 by means of the holding means 
described in connection with FIG. 1; that is, by means of the support 
bracket 13 via sockets 2. The fuel distributor line 1 with the injection 
valves 5 secured thereon by the support brackets 13 thus represents an 
element which is individually accessible, examinable and mountable, and 
which in this assembled state is directly mountable on the engine. 
Referring again to FIG. 1, openings or bored areas 20 are provided either 
in the intake pipe 19 or in the cylinders 19 of an internal combustion 
engine, into which openings 20 the nozzles 21 of the injection valves 5 
can be inserted. The fuel can be injected into the intake pipe 19 or the 
cylinders of the engine via these nozzles 21. At least one elastic sealing 
element 22 and one insulating element 23 are disposed about the nozzle 21 
of each injection valve 5. These elements 22 and 23 are supported on 
corresponding ledges in each of the openings 20 in the wall of the intake 
pipe 19 or the wall of the cylinder 19. The insulating element 23 is 
intended to prevent the transmittal of noises which result from pressure 
fluctuations from the engine into the fuel injection system. 
FIG. 2 illustrates the position of the injection valve 5 on the fuel 
distributor line 1 in accordance with the section taken along the lines 
II--II of FIG. 1. In particular, the contour of the looped portion 15 of 
the support bracket 13 is shown by way of example. The electric plug of 
the injection valve is marked with reference numeral 24. 
The embodiment of the support bracket 13 which is shown is to be considered 
only as an example. The support bracket 13 could be supported equally well 
on the fuel distributor line 1, and could be arranged to engage the 
injection valve 5 with an appropriately embodied looped portion on 
suitably embodied steps, for example. The support bracket could also be 
embodied in such a manner that it is not sustained pivotably on one end, 
but rather that, being partially arranged to surround the injection valve 
5 and the fuel distributor line 1, it engages suitably embodied detent 
areas on the injection valve or the fuel distributor line. 
Referring at this time to FIGS. 1, 3 and 4, there it is shown that in an 
advantageous manner, the fuel distributor line 1 is supported in a 
form-locking assembly on perpendicularly disposed carriers 26 that are 
associated with the intake pipe 19. These carrier members are integrated 
into the cylinder construction or the cylinders 19 of the internal 
combustion engine in the form of ribs, as clearly shown in the drawings 
denoted. The carrier members 26 partially surround the lower portion of 
the fuel distributor line 1 with a concave portion 27 which is oriented 
toward the fuel distributor line 1. The carrier members 26 each include an 
aperture 28, into which is inserted an angular leg element 29 of a clamp 
30 bent at an angle, as shown. This element is constructed out of spring 
steel wire. 
Thus, from an examination of FIG. 1 the clamp 30 includes parallel spaced 
portions, one leg of which is arranged to be bent and extend through the 
aperture 28 in the carrier member with the other end of the leg being bent 
and provided with a looped zone through which the leg element 29 is 
adapted to project. Also, as seen in FIGS. 1 and 3, the parallel spaced 
portions are integrated at the upper area, having been formed from a 
sturdy spring member with the looped integrated portions arranged to snap 
around the fuel distributor line 1. (FIG. 3). To prevent the transmission 
of noise from the internal combustion engine into the fuel injection 
system and therefrom into the body of the motor vehicle, all the securing 
points may be insulated from one another by insulating material, which 
may, for instance, be a plastic coating. 
In the exemplary embodiment of FIG. 5, the socket 34 is integrated into the 
fuel distributor line 1 and disposed at an angle relative thereto. The 
axis of the injection valve 5 thus does not extend through the 
longitudinal axis of the fuel distributor line 1. The support bracket 13, 
pivotably supported in the ring bearing 10 on the injection valve 5, 
surrounds the socket 34 with its looped portion 15 and engages a depressed 
area 35. The fuel distributor line 1 may also be secured on the carrier 
member 26 by means of a clamping element 36 and a screw connection 37. 
The foregoing relates to preferred embodiments of the invention, it being 
understood that other embodiments and variants thereof are possible within 
the spirit and scope of the invention, the latter being defined by the 
appended claims.