EP0619425A1

EP0619425A1 - Suction system arrangement in a motor vehicle tank

Info

Publication number: EP0619425A1
Application number: EP94200868A
Authority: EP
Inventors: Giovanni Bianco
Original assignee: Bitron B SpA
Current assignee: Bitron B SpA
Priority date: 1993-04-06
Filing date: 1994-04-01
Publication date: 1994-10-12
Also published as: IT229778Y1; ITMI930263V0; BR9401403A; ITMI930263U1

Abstract

A suction system arrangement in a motor vehicle tank, comprising a pump (11) connected to a filter (12) located in proximity to the tank base (10) within a calming chamber (13), in which the filter (12) and pump (11) are connected together by a variable-length conduit (21). Preferably the pump (11) is connected to the tank by elastic conduit elements (15).

Description

This invention relates to a suction system arrangement in a motor vehicle tank which enables tank base deformation to be absorbed.
In known fuel suction systems, the fuel pump is positioned within a calming chamber and is connected to it via elastic antivibration elements. The calming chamber rests on the tank base and consequently moves as a result of variations in the tank height due to deformation caused by pressure in its interior and the weight of the fuel.
With such suction system arrangements the fuel pump moves with the calming chamber and its distance from the base remains constant, allowing all the fuel contained in the tank to be drawn in, independently of its deformation.
This arrangement can lead to drawbacks in that the pump is subjected to continuous movement and its connection to the tank roof undergoes stressing. On the other hand with such an arrangement it would be impossible to fix the pump relative to the tank while at the same time achieving complete intake of the fuel contained in the tank.
The object of the present invention is to provide a new arrangement of the suction system, and in particular of the pump, which by overcoming the aforesaid drawbacks enables complete intake to be achieved in all cases independently of the deformation of the tank base.
This object is attained according to the present invention by a suction system arrangement in a motor vehicle tank, comprising a pump connected to a filter located in proximity to the tank base within a calming chamber, characterised in that said filter and said pump are connected together by a variable-length conduit.
Preferably said pump is connected to said tank by elastic conduit elements.
The characteristics and advantages of the present invention will be more apparent from the detailed description given hereinafter with reference to the accompanying schematic drawings, in which:

Figure 1 is a schematic elevational section through a first embodiment of the suction system arrangement according to the present invention; and
Figure 2 is a schematic elevational section through a second embodiment of the suction system arrangement according to the present invention.

Figure 1 schematically shows a suction system arrangement according to the invention within a tank, partially shown by its base 10. The arrangement comprises a pump 11 connected to a filter 12 located in proximity to the tank base 10 within a calming chamber 13.
The pump 11 is connected via a first port 14, inserted into an elastic conduit element 15, to the tank roof 16.
In this respect, the second end of the conduit element 15 is mounted on a pipe piece 17 extending from the tank roof 16 and connected to the fuel delivery pipe, partially shown schematically at 18.
The conduit element 15 is clamped at its two ends to the pipe piece 17 and to the pump port 14 by fixing collars 19.
The lower second port 20 of the pump 11 is connected to the filter 12 via a variable-length conduit. In the illustrated embodiment the variable-length conduit consists of a tubular bellows element 21, a first end 22 of which is fixed to the second pump port 20 by a fixing collar 19.
The second end 23 of the tubular bellows element 21 is mounted over a pipe piece 24 emerging from the filter 12 and is clamped by a further fixing collar 19.
In the embodiment shown in Figure 1, those ends 22 and 23 of the tubular bellows element 21 used for the fixing are provided with a radially outward projecting flange 25 in the region in which the bellows portion commences. These mutually opposite flanges 25 are used for locating the opposing ends of an elastic element 26, such as a compression spring, which acts to force apart the parts against which it abuts, ie it tends to maintain the bellows in its extended position.
Figure 2 shows a second embodiment of a suction system arrangement according to the invention in which the same reference numerals are used for identical elements.
It will be noted that the second port 20 of the pump 11 is connected to the pipe piece 24 emerging from the filter 12 by a different type of variable-length conduit.
The variable-length conduit consists in this embodiment of a pair of telescopic tubular elements 27 and 28, of which the outwardly facing ends are also fixed to the second port 20 of the pump 11 and to the filter pipe piece 24 by fixing collars 19.
It will be seen that between the free end of the second port 20 of the pump 11 and the free end of the pipe piece 24 there can again be interposed an elastic element 26, such as a compression spring, which acts to force apart the parts against which it abuts, ie to maintain the elements in its extended position.
In both the embodiments the pump 11 is fixed to the roof 16 by the conduit element 15 which can consist of a rubber tube acting as the antivibration element and the passage for the fuel leaving the pump. In this case the distance of the pump port from the tank base varies in accordance with the deformation of the tank base.
The arrangement according to the present invention, consisting of mounting on the suction port 20 of the pump 11 an extendable element such as the tubular bellows element 21 or the pair of tubular telescopic elements 27 and 28, solves the problem of correctly positioning the filter 12 on the base independently of tank deformation.
The possible presence of the spring 26 ensures constant adherence of the filter 12 to the inside of the base of the calming chamber 13, ie on the tank base 10.
In an alternative embodiment, both the tubular bellows element 21 and the pair of tubular telescopic elements 27 and 28 can be formed either rigid or integral with the filter pipe piece 24 .

Claims

A suction system arrangement in a motor vehicle tank, comprising a pump connected to a filter located in proximity to the tank base within a calming chamber, characterised in that said filter and said pump are connected together by a variable-length conduit.
An arrangement as claimed in claim 1, characterised in that said pump is connected to said tank by elastic conduit elements.
An arrangement as claimed in claim 2, characterised in that said elastic conduit elements are connected to the tank roof.
An arrangement as claimed in claim 1, characterised in that said variable-length conduit consists of a tubular bellows element, the ends of which are removably fixed to said filter and to said pump.
An arrangement as claimed in claim 1, characterised in that said variable-length conduit consists of a tubular bellows element formed integrally with said filter.
An arrangement as claimed in claim 1, characterised in that said variable-length conduit consists of tubular telescopic elements, the ends of which are removably fixed to said filter and to said pump.
An arrangement as claimed in claim 6, characterised in that said tubular telescopic elements consist of at least one pair of tubes, the facing ends of which are slidable one within the other, a seal gasket being provided between them.
An arrangement as claimed in claim 7, characterised in that a compression spring is positioned between said tube connected to said pump and said tube connected to said filter, and acts to force them apart.
An arrangement as claimed in claim 1, characterised in that an elastic compression element is associated with said variable-length conduit and acts to force said pump and said filter apart.