Title: Tank for a system for supplying liquid fuel, particularly LPG, to the engine of a motor vehicle
Abstract: An LPG fuel tank for motor vehicles is provided, inside, with a support, on which there can be installed in a rapid way a pump assembly including a supply pump and the corresponding electric actuating motor. Preferably, the support is also used for installing a level-sensor assembly within the tank.
Patent Number: 6,904,896 Issued on 06/14/2005 to Ricco, et al.
| Inventors:
|
Ricco; Mario (Casamassima, IT);
De Matthaeis; Sisto Luigi (Modugno, IT);
Amorese; Claudio (Corato, IT);
De Michele; Onofrio (Castellana Grotte, IT);
Satriano; Annunziata Anna (Orbassano, IT)
|
| Assignee:
|
C.R.F. Societa Consortile per Azioni (Orbassano, IT)
|
| Appl. No.:
|
773310 |
| Filed:
|
February 9, 2004 |
Foreign Application Priority Data
| Feb 11, 2003[IT] | TO2003A0096 |
| Current U.S. Class: |
123/509; 123/514 |
| Intern'l Class: |
F02M 037/04 |
| Field of Search: |
123/509,495,497,446,514
137/565,34,576
220/562-564
|
References Cited [Referenced By]
U.S. Patent Documents
Primary Examiner: Gimie; Mahmoud
Attorney, Agent or Firm: Sughrue Mion, PLLC
Claims
1. A tank for a system for supplying liquid fuel, particularly LPG, to the engine
of a motor vehicle, comprising a pump assembly set within the tank, including a
pump for suctioning the liquid fuel contained within the tank and feeding it to
a pipe for supply of the fuel, and an electric motor for actuating the pump,
wherein the pump assembly is installed by fast-connection means on a support
fixed within the tank,
wherein said support defines a seat for receiving the pump assembly and is provided
with fast-clamping means for clamping the pump assembly within said seat.
2. The tank according to claim 1, wherein said support is also used for supporting
a level-sensor assembly within the tank.
3. The tank according to claim 1, wherein said support comprises one or more
bottom surfaces, which define a bottom supporting surface for the pump assembly,
one or more vertical walls extending from said bottom surfaces to define the seat
of the pump assembly, and one or more top surfaces for containing the pump assembly
at the top.
4. The tank according to claim 3, wherein said support has a central vertical
wall and two side vertical walls provided with means for hooking an elastic retention
member for holding the pump assembly in its seat.
5. The tank according to claim 1, wherein said pump assembly is set within a
cylindrical container positioned within the seat of the support.
6. The tank according to claim 4, wherein said central vertical wall has, on
the outside, supporting appendages for a level-sensor assembly.
7. The tank according to claim 1, wherein the aforesaid support consists of a
single element of stamped and bent metal plate.
Description
BACKGROUND OF THE INVENTION
The present invention relates to systems for supplying liquid fuel, in particular
LPG, to the engines of motor vehicles.
The systems of the type specified above typically comprise a liquid-fuel tank,
a plurality of injectors associated to the cylinders of the engine for injecting
the fuel in the liquid state into said cylinders, a manifold or rail for supplying
the liquid fuel to said injectors, a pipe for the supply of the liquid fuel from
the tank to the aforesaid rail, a return pipe for taking the LPG supplied in excess
to the injectors back to the tank, a pump submersed in the liquid fuel present
in the tank for supplying the liquid fuel through the delivery pipe, and an electric
motor for controlling the pump.
LPG supply systems of the type referred to above are, for example, described
in the European patent No. EP-B-0 725 205 and in the European patent No. EP-B-0
922 851 in the name of the present applicant, as well as in the corresponding U.S.
Pat. No. 5,592,924 and U.S. Pat. No. 6,050,237.
SUMMARY OF THE INVENTION
The purpose of the present invention is to provide a tank for a supply system
of the type specified above that may be assembled and installed with simple and
rapid operations and that will moreover enable operations of maintenance and/or
replacement of the components arranged within the tank to be carried out in a simple
and rapid way.
With a view to achieving said purpose, the subject of the present invention
is a tank for a system for supplying liquid fuel, particularly LPG, to the engine
of a motor vehicle, comprising a pump assembly set within the tank, including a
pump for suctioning the liquid fuel contained within the tank and feeding it to
a pipe for supply of the liquid fuel, and an electric motor for actuating the pump,
characterized in that the pump assembly is installed by means of fast-connection
means on a support fixed within the tank.
According to a further characteristic, the aforesaid support defines a
seat for receiving the pump assembly and is provided with fast-clamping means for
clamping the assembly within said seat.
In a preferred embodiment, the aforesaid support is also used for supporting a
level-sensor device that is also set within the tank.
Thanks to the characteristics described above, the pump assembly, after being
pre-assembled, can be installed, with simple and rapid operations, within the tank.
Tanks of this type typically have an opening that is closed by a flange carrying
the various connectors for electrical and hydraulic connection of the components
arranged within the tank to the external electrical and hydraulic circuits. The
aforesaid opening can be used for inserting the pump assembly within the tank.
Thanks to the invention, the assembly can be anchored to the tank in a simple and
rapid way, without any need for laborious operations of connection. Said simplicity
of assembly is reflected also in an ease and rapidity of removal of the pump assembly
from the tank, for possible replacement or maintenance.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the invention will emerge from
the ensuing description with reference to the annexed drawings, which are provided
purely by way of non-limiting example and in which:
FIG. 1 is a schematic view of a system for supplying LPG to the engine of a
motor vehicle;
FIG. 2 is a sectioned perspective view of an embodiment of the tank according
to the invention;
FIG. 3 is a cross-sectional view of the tank of FIG. 2; and
FIGS. 4 and 5 are two perspective views of a detail of FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, the reference number
1 designates as a whole an LPG fuel tank
built according to the known art, for supplying the LPG to a plurality of injectors
I associated to the various cylinders of the engine. The tank
1 has a hollow
structure
2 built so as to guarantee tightness at the working pressures
expected for a system of the type in question. The hollow structure
2 has
a top opening closed by a service flange
3 carrying the various fitting
and connection elements for connection of the tank to the supply system. For this
purpose, the tank
1 has a first through opening
4, through which
there is installed the structure of an assembly
5 connected to a line
6
for delivery of the LPG to a distribution manifold or rail
7, which distributes
the LPG between the various injectors I. The assembly
5 includes a shut-off
solenoid valve
8 designed to close, interrupting communication of the tank
with the outside environment in pre-determined emergency conditions, as well as
a flow-limiting valve
9. The assembly
5 receives the LPG through
the line
10 from the pump
11 driven by an electric motor
11a,
the structure of which is connected by means of a connection element
12
to the service flange
3. The assembly of the pump
11 may in any case
be obtained in any other way, as will be indicated also in what follows. To the
structure of the pump
11 there is moreover connected the structure of a
sensor device
13 for detecting the level of LPG. The electrical supply of
the solenoid valve
8, of the pump
11, and of the sensor
13
is guaranteed by an electrical connector
14 that is mounted through a through
opening
15 of the service flange
3. The latter moreover has a further
through opening
16, within which there is installed an assembly
17
including two valves
18 and
19. The valve
18 is a return valve,
which is connected to a line
20 for flow back into the tank of the LPG supplied
in excess to the rail
7. The valve
19 is the valve used for filling
the tank and is associated to a further level-sensor
21. Associated to the
flange
3 is moreover a safety valve
22, which prevents the pressure
within the tank from exceeding a pre-determined threshold value.
FIG. 1 shows a traditional embodiment of tank, in which the flange
3
has through holes traversed by the various components described above. The present
invention could also be made with a tank having an innovative structure that has
formed the subject of the preceding Italian patent application No. TO2001A000360
in the name of the present applicant, in which at least some of the aforesaid components
are fixed to the bottom surface of the plate, without passing through it. Furthermore,
as already mentioned, in the case of the invention operation of the electric motor
11a is not controlled by a level-sensor
13, but rather by
the innovative means that will be described in what follows. Finally, also installation
of the engine-pump assembly, in the preferred embodiment of the invention, is different
from what is indicated purely by way of example in FIG. 1, with reference to the
known art.
FIGS. 2 to
5 illustrates a preferred embodiment of an LPG tank according
to the invention. In FIG. 2, the parts corresponding to the ones illustrated in
FIG. 1 are designated by the same reference numbers. In the case of the tank according
to the invention, the pump assembly, comprising the supply pump
11 for delivering
the LPG and the corresponding electric actuating motor
11a, is set
within a cylindrical container
30. Said container guarantees that the part
of liquid in which the pump assembly is submersed is as little as possible subject
to shaking when the motor vehicle on which the tank is installed is in motion.
The said pump assembly is in itself of a known type and is not therefore illustrated
in detail in the annexed drawings. It can be built according to any conventional
technique. The basic idea of the invention lies in the fact that the pump assembly
can be installed and removed rapidly for the reason that it is received in a seat
31 (see, for example, FIG. 4) defined by a support made of metal plate
32,
which is welded on the bottom of the tank
1.
In the example illustrated, the support made of metal sheet
32 is made
of a single piece by means of bending, starting from a plane metal plate, so as
to define (see FIGS. 3-5) a central vertical wall
32A, two side vertical
walls
32B, two horizontal bottom flanges
32C projecting from the
bottom edges of the side walls
32B and which define a bottom supporting
surface for the pump assembly
11 with the corresponding container
30,
and two top horizontal flanges
32D which project from the top edges of the
vertical walls
32B and define a top plane for containment of the pump assembly.
As may be seen in FIG. 3, the support
32 is fixed on the bottom of a tank
1, which has a substantially cylindrical conformation and is designed to
be set horizontally. The sharp bottom edges of the side walls
32B of the
support
32 are tangential to the internal surface of the tank, which has
a circular cross section, and are joined thereto by means of welded joints
33.
As may be seen in the drawings, the pump assembly
11, including also the
external cylindrical container
30, is received in the seat
31 defined
by the support
32 and clamped in said position by means of a retention member
consisting of a plate made of metal material or plastic material
34, provided
at one end with a buckle
35 hooked on a tooth
36 projecting from
one of the two side walls
32B. The opposite end of the plate
34 is
instead connected by means of a helical spring
37 to the other side wall
32B, in which a notch
38 is formed that receives the corresponding
end of the spring
37.
In the preferred embodiment, the central wall
32A has a bottom portion
32E with a horizontal plane appendage
39. Furthermore, the central
wall
32A has, at the top, a vertical portion
32F terminating in a
horizontal plane appendage
40, in a position set opposite to the appendage
39. The appendages
39,
40 function as supports for a level-sensor
assembly
13, which, in the example illustrated, is built in conformance
with a co-pending patent application in the name of the present applicant. According
to said solution, the level-sensor assembly has a vertical column
41 fixed
at its end to the two appendages
39,
40 and a float, in the form
of an annular body
42, installed in a slidable way, with play, on the vertical
column
41. According to the teachings specified in the co-pending patent
application in the name of the present applicant that has already been cited, within
the column
41 there is provided a vertical aligned series of reed relays
that are activated selectively by permanent magnets incorporated in the float
42
and that consequently are able to issue at output an electrical signal that depends
upon of the position of the float
42 with respect to the column
41.
As already said, the structure and the conformation of the level-sensor form in
themselves a subject of a separate patent application. For the purposes of the
present invention, said device is in any case advantageous in so far as it enables
the same support
32, to which the pump assembly is anchored, to be used
also for supporting the level- sensor assembly. Obviously, it would likewise be
possible to adopt a support for anchorage of the pump assembly, without envisaging
an anchorage thereon also of the level-sensor assembly. Furthermore, for the purposes
of the present invention, the level-sensor assembly could be even altogether different
from what is illustrated herein with reference to the preferred embodiment of the invention.
Once again with reference to said preferred example, the column
41 of
the level-sensor assembly has, at the bottom, an end disk
43, which rests
on the surface of the bottom appendage
39, which has a hole
44 for
centring of the column
41. Likewise, the top end of the column
41
is provided with a top disk
45 with two holes
46 set diametrically
opposite to one another, which are engaged on threaded grub-screws
47 that
project from the appendage
40 and receive lock-nuts
48 (see FIG.
4). Once again with reference to the drawings, the appendage
40 has
a notch
49 for engagement and installation of the column
41 of the
level-sensor assembly.
In installation of the tank according to the invention, the pump assembly is
installed
within the tank after the support
32 has already been welded in the way
described on the bottom of the latter. The pump assembly is introduced through
the opening, which is closed during normal operation by the flange
3. The
pump assembly is set in the seat
31 defined by the support
32 and
clamped there by means of the retention member consisting of the plate
34
with the hook
35 and the spring
37. Also the level-sensor assembly
is installed on the support
32 after the support
32 has been installed
within the tank.
As emerges clearly from the foregoing description, thanks to the characteristics
indicated, the operations of installation, maintenance and/or replacement of the
pump assembly in the tank according to the invention are particularly simple and
rapid. The structure of the tank is moreover particularly simplified, also as regards
the support of the level-sensor assembly. Finally, the pre-arrangement of a support
on which the pump assembly and possibly also the level-sensor assembly can be anchored
in a simple and rapid way enables convenient adaptation of said components to tanks
that have different structures and conformations.
Of course, without prejudice the principle of the invention, the details of construction
and the embodiments may vary widely with respect to what is described and illustrated
herein purely by way of example, without thereby departing from the scope of the
present invention.
*
