GB2255554A

GB2255554A - Vehicle fuel tank feed pipe with vent pipe

Info

Publication number: GB2255554A
Application number: GB9209422A
Authority: GB
Inventors: Palu Attilio Dal
Original assignee: Fabbrica Italiana Serrature Torino FIST SpA
Current assignee: Fabbrica Italiana Serrature Torino FIST SpA
Priority date: 1991-05-03
Filing date: 1992-04-29
Publication date: 1992-11-11
Anticipated expiration: 2012-04-29
Also published as: FR2676026B3; GB2255554B; ITTO910332A0; FR2676026A1; ITTO910332A1; DE4214076A1; GB9209422D0; IT1245524B

Description

2 z-3 55 54 VEHICLE FUEL FEED MEMBER The present invention relates to a

fuel feed member between the filler and fuel tank of a motor vehicle.

Feed members of the aforementioned type currently comprise a feed pipe, and a vent pipe inside or outside the feed pipe, for directing any air inside the tank to the filler.

Feed members in which both pipes are made of plastic. e.g. nylon. have already been proposed and manufactured, and present improved characteristics in terms of working life, cost and reliability as compared with metal pipes. A major drawback of plastic, however, is that the fuel fed into the filler may produce electrostatic charges which, in extreme circumstances, may spark off an explosion. Though this is highly unlikely. for safety reasons, feed members with plastic pipes are banned in several countries, so that metal pipes are still predominantly employed.

It is an object of the present invention to provide a fuel feed member designed to overcome the 2 - CIP above drawback, i.e. which entirely eliminates any risk of sparking or explosion, while at the same time providing for all the advantages afforded by the use of plastic pipes.

According to the present invention, there is provided a vehicle fuel feed member comprising a fuel feed pipe connecting the filler to the fuel tank on the vehicle; and a vent pipe for directing the air inside the tank to the filler; said feed and vent pipes being made of plastic material; characterized by the fact that it comprises means defining an electrically conductive path extending inside said feed pipe for eliminating electrostatic charges.

A number of preferred, non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which:

Fig.1 shows a partially sectioned side view of a first embodiment of the fuel feed member according to the present invention; Fig.s 2 and 3 show the same view as in Fig.1 of a further two embodiments of the fuel feed member according to the present invention; Fig.8 4 to 6 show enlarged partially sectioned details of the members in fig.s 1 to 3.

Number 1 in Fig.1 indicates a fuel feed member extending from a filler 2 to a tank 3, the latter both being shown only partially for the sake of simplicity.

- 3 -C L Member 1 comprises a feed pipe 4 along which fuel is fed from filler 2 to tank 3; and a vent pipe 5 which, in the Fig.1 embodiment, is fitted inside pipe 4, and provides for feeding the air in tank 3 towards filler 2.

Pipe 4 presents a main central portion 6 undulated both internally and externally; and two substantially smooth end portions 7, 8. In known manner not shown in detail, portion 8 surrounds a first sleeve (not shown) to which one end of pipe 5 is connected by means of coupling 10 (shown partially), and which in turn is connected to a second sleeve 9 extending from tank 3. The connection of portion 8 and the two sleeves is ensured by an annular element 11, possibly also with the aid of metal rings (not shown). The other end portion 7 of pipe 4 engages a tubular portion 12 of filler 2. to which the other end 14 of pipe 5 is connected by a coupling 13 formed in one piece with tubular portion 12. As with end portion 8, an annular element 15 is provided for ensuring the connection of end portion 7 and tubular portion 12.

According to the present invention, plastic pipes 4 and 5 present means constituting a conductive path for grounding the electrostatic charges produced by the fuel fed through the filler.

More specifically. according to a first embodiment, vent pipe 5 is made of conductive plastic material, e.g. acetal resin containing conductive particles such as carbon black, graphite or powdered fo aluminium- or copper-based metal, as shown schematically in the partially sectioned detail in Fig.4, in which the dotted portions indicate the conductive particles.

According to a second embodiment, vent pipe 5 is made of normal nonconductive plastic material (nylon) and surrounded by a braid of electrically conductive material, suchas copper or aluminium. This solution is shown in the partially sectioned detail in Fig.5, in which 17 indicates the actual body of pipe 5,, and 18 the braid surrounding body 17.

According to a third embodiment, vent pipe 5 is coated externally with conductive (e.g. nickel-based) paint, or metallized (silver plated) in the same way as a mirror. In this case, the main central portion of the vent pipe is also preferably smooth, as shown in Fig.2, which shows a feed member 11 identical to that of Fig.1, except for the design of the main portion of vent pipe 51. A detail of vent pipe 51 is shown in Fig.6. in which 19 indicates the actual body of vent pipe 51 made of normal plastic material (e.g. nylon),, and 20 the painted, silver plated, or co- extruded conductive layer.

In all the above embodiments, the outer surface of tubular portion 12 of filler 2 is grounded, e.g. connected to the vehicle body (as shown schematically by 21 in Fig.s 1 and 2), and a conductive path is formed between end 14 of vent pipe 5, 51 and said outer surface. Said path is preferably defined by tubular k t - 5 !h portion 12 itself, which is made of conductive plastic material of the type indicated above.

In the case of a vent pipe extending outside pipe 4, as shown by 511 in Fig.3, wherein ends 22 and 23 of the vent pipe are fitted through the wall of pipe 4 close to end portions 7 and 8, the conductive path for the electrostatic charges is formed on pipe 4, which, for this purpose, may be made of conductive plastic material in exactly the same way as described for vent pipe 5 and shown in detail in Fig.4. Alternatively, pipe 4 may present a conductive lining consisting of a braid of copper or other highly conductive metal, or a painted, silver plated, or co- extruded inner surface layer, as provided externally on vent pipes 5, 51 and shown in Fig.s 5 and 6. The latter solution, however, is less recommendable, due to the elasticity required of pipe 4 and consequently also of the lining. If made of conductive plastic material, pipe 4 may be grounded directly close to filler 2 (or via conductive plastic tubular portion 12). otherwise, a conductive path must be formed, e.g. by making tubular portion 12 of filler 2 of conductive material, and providing electrical connecting elements between the inside of pipe 4 and tubular portion 12.

In actual use, the electrostatic charges on pipes 5, 51 and 4 are grounded by the conductive path formed as described above, thus eliminating any risk of sparking or explosion, while at the same time providing - 6 fir for all the advantages afforded by manufacturing the pipes from plastic material.

To those skilled in the art it will be clear that changes may be made to the feed member as described and illustrated herein without, howeverf departing from the scope of the present invention. In particular, an internal vent pipe 5 with a metal braid covering may also present a smooth outer surface, just as pipe 4 may present a smooth silver plated, painted or co-extruded inner surface, providing it is sufficiently elastic. Moreover, when vent pipe 5 is fitted inside feed pipe 4, though it is simpler and cheaper to form the conductive path on vent pipe 5, in some cases, it may be formed alternatively or additionally on pipe 4. Regardless of which solution is adopted, however, the conductive material need not necessarily cover the entire outer surface of the vent pipe or the entire inner surface of the feed pipe, but may simply consist of a conductive strip extending along the full length of the pipe. The conductive path inside pipe 4 may be grounded differently, e.g. by means of a conductive portion through the walls of pipe 4 and/or filler 2, providing this does not affect the fuel sealing capacity of the feed member. Finally, the conductive path may be formed in any number of different ways using the technology and materials currently available.

g ri h.

Claims

CLAIMS (Or 1) - A vehicle fuel feed member (1) comprising a fuel feed pipe

(4) connecting the filler (2) to the fuel tank (3) on the vehicle; and a vent pipe (5; V; 5u) for directing the air inside the tank (3) to the filler (2); said feed (4) and vent (5; 59; 511) pipes being made of plastic material; characterized by the fact that it comprises means (4; 5; 18; 20, 121 21) defining an electrically conductive path extending inside said feed pipe (4) for eliminating electrostatic charges.
2) - A member as claimed in Claim 1, characterized by the fact that said conductive path (4; 5; 18; 20r 12r 21) extends along the entire feed member (1) and is grounded (21) at said filler (2).
3) - A member as claimed in claim 1 or 2, characterized by the fact that said conductive path (4; 5; 18; 20l 12r 21) is connected electrically to said filler (2), and by the fact that said filler (2) is grounded (21).
4) - A member as claimed in Claim 3. wherein said vent pipe (5; 51) extends inside said feed pipe (4); characterized by the fact that said conductive path (4; 5; 18; 20, 12, 21) is formed on said vent pipe (5; 51)r and by the fact that said filler (2) defines means (12. 13) for mechanically and electrically connecting said vent pipe (5; 51).
c 5) A member as claimed in Claim 3. wherein said vent pipe (511) extends outside said feed pipe (4); cha racterized by the fact that said conductive path (4; 5; 18; 20, 12, 21) is formed on said feed pipe (4), and by the fact that said filler (2) defines means for mechanically and electrically connecting said feed pipe (4).
6) - A member as claimed in one of the foregoing claims from 1 to 5. characterized by the fact that said filler (2) is made of electrically conductive plastic material.
7) - A member as claimed in one of the foregoing Claims from 1 to 6, characterized by the fact that at least one of said feed and vent pipes (4, 5) is made of electrically conductive plastic material.
8) - A member as claimed in one of the foregoing Claims 1-4, 6 and 7, wherein said vent pipe (5) extends inside said feed pipe (4); characterized by the fact that said vent pipe (5) is made of electrically conductive plastic material.
9) - A member as claimed in one o the foregoing Claims from 1 to 3 and 5 to 7. wherein said vent pipe (511) extends outside said feed pipe (4); characterized by the fact that said feed pipe (4) is made of electrically conductive plastic material.
10) - A member as claimed in one of the foregoing Claims from 6 to 9. characterized by the fact that said R G plastic material consists of acetal resin containing conductive particles.
11) - A member as claimed in Claim 10, characterized by the fact that said conductive particles consist selectively of carbon black, graphite and powdered metal.
12) - A member as claimed in one of the foregoing Claims from 1 to 6, characterized by the fact that at least one of said feed and vent pipes (4, 5) presents a covering (18; 20) of electrically conductive material on the surface facing the other (5, 4) of said feed and vent pipes.
13) A member as claimed in Claim 12,, characterized by the fact that said covering comprises a metal braid (18).
14) - A member as claimed in claim 13, characterized by the fact that said braid (18) is made of copper or aluminium.
15) - A member as claimed in Claim 12.. characterized by the fact that said.covering comprises a metal coating (20).
16) - A member as claimed in claim 12.. characterized by the fact that said covering comprises a strip of metal material.
17) - A member as claimed in Claim 12j, characterized by the fact that said covering comprises a coating of electrically conductive paint (20).
- 10 ro 18) - A member as claimed in claim 171 characterized by the fact that said paint coating (20) comprises metal, preferably nickel, pigments.
19) - A member as claimed in one of the foregoing Claims from 12 to.18, wherein said vent pipe (5; 51) extends inside said feed pipe (4); characterized by the fact that said covering (18; 20) is applied on the outer surface of said'vent pipe (5; 51).
20) A member as claimed in one of the foregoing Claims from 12 to 19, characterized by the fact that said vent pipe (51) presents a smooth outer surface.

21) - A member as claimed in one of the foregoing Claims from 12 to 18, wherein said vent pipe (511) extends outside said feed pipe (4); characterized by the fact that said covering 818; 20) is applied to the inner surface of said feed pipe (4).

22) - A vehicle fuel feed member, substantially as described and illustrated herein with reference to the accompanying drawings ts