Arrangement for feeding of fuel from supply tank to internal combustion engine of power vehicle

An arrangement for feeding of fuel to an internal combustion engine of a power vehicle comprises a supply tank having a tank bottom, a feeding aggregate arranged in the supply tank, a receiving part holding the feeding aggregate, a holder mounted on the tank bottom, and vibration damping unit through which the receiving part is connected with the holding ring, the vibration damping unit including a metal spring and a rubber elastic buffer through which the metal spring is mounted on at least one of the receiving part and the holder.

BACKGROUND OF THE INVENTION 
The present invention relates to an arrangement for feeding fuel from a 
supply tank to an internal combustion engine of a power vehicle. 
Arrangements of the above mentioned general type are known in the art. One 
of such arrangements is disclosed for example in the German document DE-PS 
3, 602, 135. In this arrangement a receiving part for the feeding 
aggregate is supported on a holder of the tank bottom through a vibrations 
damping means which include a plurality of elastic webs. The webs extend 
tangentially to the axis of the roll-shaped aggregate and their ends are 
connected with the feeding aggregate receiving part on the one hand and 
with the tank bottom holder on the other hand. The thusly formed and 
arranged damping means are, however, incapable of dampening the low 
frequencies. Therefore, such frequencies reach the tank bottom undampened, 
and the tank bottom acts as a resonance body producing undesirable noise. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide an 
arrangement for feeding fuel from a supply tank to an internal combustion 
engine of a power vehicle which avoids the disadvantages of the prior art. 
In keeping with these objects and with others which will become apparent 
hereafter, one feature of the present invention resides, briefly stated, 
in an arrangement for feeding of fuel to an internal combustion engine of 
a power vehicle, which comprises a supply tank having a tank bottom, a 
feeding aggregate arranged in said supply tank, a receiving part holding 
said feeding aggregate, a holder mounted on said tank bottom, and 
vibration damping means through which said receiving part is connected 
with said holder, said vibration damping means including a metal spring 
and a rubber elastic buffer through which said metal spring is mounted on 
at least one of said receiving part and said holder. 
When the arrangement is designed in accordance with the present invention, 
the vibration damping means has two different operating dampers which 
efficiently dampen both the high frequencies by the buffer, and the low 
frequencies by the metal spring, so that the undesirable body sounds are 
prevented. 
Still another feature of the invention is that the cup has a cup wall and 
the bowl has a bowl wall, the one end of the metal spring being connected 
with the cup wall and the other end of the metal spring being connected 
with the bowl wall. 
The metal spring can be formed as a spiral spring. The spiral spring has an 
inner end held on said receiving part and an outer end connected with said 
holder. The receiving part can be cup-shaped and has a cup wall provided 
with a radial projection, and the spiral spring is fixed on an outer 
surface of said cup wall. The buffer can be hat shaped and arranged on 
said projection, and the spiral spring can have an inner winding 
surrounding said buffer. The holder can have a recess, and the outer end 
of said spiral spring engages in said recess and is fixed in it. The 
projection of the receiving part and the radial projection of the holder 
can form means for limiting of vibrations of the receiving part relative 
to the holder. 
In accordance with another feature, said receiving part is cup-shaped and 
has a cup in which said feeding aggregate is arranged, the said holder is 
bowl-shaped and having a bowl bottom connected to the tank bottom, and the 
metal spring having one end connected with the cup and another end 
connected with the bowl. 
The novel features of the present invention are set forth in particular in 
the appended claims. The invention itself however both as to its 
construction and its manner of operation can be best understood from the 
following description of preferred embodiments which is accompanied by the 
following drawings.

DESCRIPTION OF A PREFERRED EMBODIMENT 
FIG. 1 shows a fuel supply tank 10, in which a fuel feeding unit 12 is 
arranged. A pressure conduit 16 is connected with a pressure pipe 14 of 
the fuel feeding unit 12 and leads to an internal combustion engine 18. 
During the operation of the internal combustion engine the fuel feeding 
unit 12 supplies the fuel from the supply tank 10 to the internal 
combustion engine 18. 
As can be seen specifically from FIG. 2, a fuel feeding aggregate of the 
fuel feeding unit 12 is roller shaped and sits in a cup-shaped receiving 
part 20. The receiving part 20 is inserted in its lower region provided 
with a cup bottom 22, in a bowl-shaped holder 24. The bowl-shaped holder 
24 is fixedly connected with the bottom 26 of the fuel supply tank 10. For 
this purpose, the holder 24 has a mounting ring 28 which is for example 
welded with the tank bottom 26. The wall of the bowl-shaped holder 24 in 
turn is connected by a plug-rotary connection which is known as a bayonet 
connection, with the mounting ring 28. 
The fuel feeding aggregate 32 is supported in the receiving part 20 in its 
lower region through a centering sleeve 34 and a filling ring 36. In its 
upper region the fuel feeding aggregate 32 is centered in the cup-shaped 
receiving part 20 by a centering ring 38 and a compensating ring 40. A 
substantially vertical rising pipe 42 is formed on the centering sleeve 
34. The medium supplied from a first pump stage of the feeding aggregate 
32 is pumped through the rising pipe 42 in direction of the arrow 44 to 
the cup-shaped receiving part 20. From there, it is aspirated by a 
pressure stage of the feeding aggregate 32 and supplied through the 
pressure pipe 14 to the pressure and feeding conduit 16 and to the 
internal combustion engine 18. 
The fuel feeding unit 12 includes, in addition to the fuel feeding 
aggregate 32, the receiving part 20 and the holder 24. The feeding 
aggregate 32 has a suction filter 46 extending in the opening of the 
mounting ring 28. The mounting ring 28 has throughgoing openings not 
shown, so that the fuel to be fed can flow from the supply tank 10 to the 
suction filter 46. 
The connection between the receiving part 20 and the holder 24 is performed 
by the following structure. The cup-shaped receiving part 20 has a radial 
projection 48 provided on its outer surface and shown in FIG. 2. A rubber 
elastic buffer 50 is arranged on the projection 48. The rubber elastic 
buffer 50 is hat shaped. An inner winding 51 of a spiral spring 52 engages 
with the projection 48 or the buffer 50. Several windings of the spiral 
spring 52 surround the projection 48 of the cup-shaped receiving part 20. 
The outer free end 54 of the spiral spring 52 is fixed to the bowl-shaped 
holder 24. For this purpose, the outer end 54 which is curved 
substantially in radial direction of the spiral spring 52, engages in a 
groove-shaped recess of the holder 24 arranged on a radial projection 56 
of the holder. Thereby, a supporting connection between the holder 24 and 
receiving part 20 is produced. Since the above arrangement on the 
periphery of the holder 24 and the receiving part 20 in this example is 
provided in triplicate, a secure supporting connection is obtained. 
The spiral spring 52 made of metal, preferably spring steel is especially 
suitable to dampen low frequencies generated from the feeding aggregate 
32. The hat-shaped rubber buffer 50 in contrast absorbs preferably the 
high frequencies of the feeding aggregate 32. These two dampers which 
operate counter to one another form therefore a reliable vibration damping 
means 60 which efficiently dampen the frequencies within a broad spectrum. 
A further special feature of the present invention is that the projection 
48 of the receiving part 20 and the radial projection 56 of the holder 24 
are arranged relative to one another so that the projection 56 forms an 
abutment cooperating with the projection 48 or with the surrounding spring 
convolutions to provide a limit. It must absorb the vertical movements of 
the receiving part 20 relative to the holder 24, before the suction filter 
46 abuts against the tank bottom 26. 
What is important is that the feeding device has vibration damping means 60 
including a metal spring 52 and a rubber elastic buffer. It is recommended 
that both ends 51 and 54 of the spiral spring 52 are supported in the 
rubber elastic buffers, also when in the respective embodiment the inner 
winding 51 of the spiral spring 52 is fixed on a rubber buffer 50. 
It will be understood that each of the elements described above, or two or 
more together, may also find a useful application in other types of 
constructions differing from the types described above. 
While the invention has been illustrated and described as embodied in an 
arrangement for feeding of fuel from a supply tank to an internal 
combustion engine of a power vehicle, it is not intended to be limited to 
the details shown, since various modifications and structural changes may 
be made without departing in any way from the spirit of the present 
invention. 
Without further analysis, the foregoing will so fully reveal the gist of 
the present invention that others can, by applying current knowledge, 
readily adapt it for various applications without omitting features that, 
from the standpoint of prior art, fairly constitute essential 
characteristics of the generic or specific aspects of this invention.