GB2306605A

GB2306605A - Longitudinally flexible pipe

Info

Publication number: GB2306605A
Application number: GB9522488A
Authority: GB
Inventors: Bernard Renzo; Michel Robinault
Original assignee: Draftex Industries Ltd
Current assignee: Laird Holdings Ltd
Priority date: 1995-11-02
Filing date: 1995-11-02
Publication date: 1997-05-07
Also published as: GB9522488D0

Abstract

The pipe, e.g. for connecting a vehicle fuel tank to the vehicle fuel filling inlet, has end connectors and a wall which is longitudinally flexible, e.g. of bellows form. The pipe is manufactured by blow-moulding from a thermoplastics material which is impermeable to fuel, and is provided with a fire- resistant layer, e.g. of rubber or foam. The connectors may be male or female and releasable.

Description

PIPES The invention relates generally to pipes. More specifically but not exclusively it relates to fuel carrying pipes or the like in motor vehicles.

According to the invention there is provided a pipe comprising a longitudinally extending, generally tubular section, each end of which is provided with releasable fixing means in which the wall of the tubular section is longitudinally flexible.

According to the invention there is further provided a fuel pipe for a motor vehicle and for connecting a fuel-filling inlet on the vehicle body with a fuel tank of the vehicle, the pipe comprising a longitudinally flexible tubular section made of material substantially impermeable to fuel, an envelope of fire-resistant material around the outside of the tubular section which substantially does not interfere with the latter's longitudinal flexibility, and fixture means for fixing the ends of the pipe to the fuel-filling inlet and the fuel tank respectively.

Fuel carrying pipes embodying the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings in which: Figure 1 is a longitudinal cross-sectional view of one of the pipes; Figure 2 is a longitudinal cross-section view of male and female connectors used to secure the pipe of Figure 1 in position in use; and Figure 3 is a longitudinal cross-sectional view of a modified one of the pipes.

Figure 1 shows a fuel carrying pipe 1 for connection between a fuel tank and the fuel filling inlet in a motor vehicle. The fuel pipe 1 comprises two sections, a generally tubular pipe section 3 and mounting sections 5,6 disposed at opposite ends of the tubular pipe section 3.

The tubular pipe section 3 is provided with one or more bellows turns 7 at spaced apart intervals along its length. In addition, the pipe section 3 is covered with an envelope 9 of fire-resistant material such as rubber.

The envelope 9 is fitted to the pipe 3 by means of integrally formed clips 11 which locate and lock in place in grooves 13 integrally formed on the pipe 3. Instead, the envelope 9 can be fitted in position by any other suitable means.

The fuel carrying pipe 1 is attached to the motor vehicle by lockable connectors disposed at opposite ends of the pipe 1. Figure 1 shows a female type connector 5 at the end of the pipe 3 to be attached to the fuel tank and a male type connector 5 at the end of the pipe to be attached to the fuel filling inlet. Using this configuration, it will be appreciated that the connectors on the fuel tank and the fuel filling inlet will be male and female respectively.

Figure 2 shows the male connector 5 of the fuel carrying pipe 3 attached to a female connector 14 at the fuel filling inlet. Connector 14 in this case is similarly shaped to the female connector 6 of the pipe 3 (see Figure 1). At the opposite end of the pipe 3, its female connector 6 would be attached to a male connector connected to the fuel tank.

The geometry of the connectors shown provides good sealing and impermeability to fuel, whilst being quick and easy to mount on the motor vehicle.

The male and female connectors 5,6 are integrally formed on the fuel carrying pipe.

It will be appreciated that the male-female configuration may be reversed, with the male connector 5 being disposed at the end of the pipe 1 to be connected to the fuel tank and the female connector 6 being disposed at the end of the piep 1 to be connected to the fuel filling inlet.

Additionally, any other suitable geometry may be used for the connectors which will allow easy removal and reconnection should the pipe 1 need to be removed from the motor vehicle.

The fuel carrying pipe 3 is formed from a thermoplastics material impermeable to fuel in a single step blow-moulding process. However, it will be appreciated that any plastics material possessing suitable impermeability to fuels may be used. The fire-resistant envelope 9 is formed from rubber which is mounted on the pipe 3 subsequent to the blow-moulding process. Again, it will be appreciated that any suitable fire-resistant material may be used to form the envelope 9.

In position on the motor vehicle, the bellows turns 7 will deform to absorb any shocks or vibrations induced by vehicle motion. In the event of an accident, the bellows turns 7 will, again, deform to absorb the shock and the pipe 1 will not catastrophically fracture. Any risk of fire will be reduced by the fire-resistant envelope 9.

The rubber envelope 9 is sufficiently flexible so that it does not interfere with the shock-absorbing capability of the bellows turns 7.

The improved fuel carrying pipe 1 is therefore impermeable to fuel and resistant to fire and will absorb shocks and vibrations without fracturing. In addition, the pipe 1 is both simple and quick to produce and fit to the motor vehicle.

In a modified version shown in Figure 3, the fire-resistant envelope 9 is replaced by a covering of foam 15. This foam is also fire-resistant. The foam 15 is injected onto the pipe during the blow-moulding process, thereby making the manufacture of the fuel carrying pipe a single step process. Again, the foam 15 does not interfere with the longitudinal flexibility of the bellows turns 7.

It will be appreciated that the pipe 1 need not be a fuel carrying pipe on a motor vehicle but may be any other pipe which must resist shocks and vibrations or be fireresistant.

Claims

1. A pipe, comprising a longitudinally extending, generally tubular section, each end of which is provided with releasable fixing means in which the wall of the tubular section is longitudinally flexible.

2. A pipe according to claim 1, in which the wall of the tubular section is provided with one or more bellows turns.

3 A pipe according to claim 1 or 2, in which the tubular section is formed from a material impermeable to fuel.

4. A pipe according to claim 3, in which the material is a thermoplastics material.

5. A pipe according to any preceding claim, in which the fixing means are formed from thermoplastics material.

6. A pipe according to any preceding claim, in which the fixing means are integrally formed with the tubular section.

7. A pipe according to any preceding claim, in which the tubular section is covered with a fire-resistant material.

8. A pipe according to claim 7, in which the fireresistant material is rubber.

9. A pipe according to claim 7, in which the fireresistant material is foam.

10. A pipe according to any preceding claim, formed by blow moulding.

11. A pipe according to any one of claims 1 to 9, formed by injection moulding.

12. A pipe according to any preceding claim, which is a fuel carrying pipe in a motor vehicle.

13. A pipe according to claim 12, adapted to connect a fuel filling inlet to a fuel tank on the motor vehicle.

14. A pipe according to any preceding claim, in which the fixing means are male and female type connectors.

15. A fuel pipe for a motor vehicle and for connecting fuel-filling inlet on the vehicle body with a fuel tank of the vehicle, the pipe comprising a longitudinally flexible tubular section made of material substantially impermeable to fuel, an envelope of fire-resistant material around the outside of the tubular section which substantially does not interfere with the latter's longitudinal flexibility, and fixture means for fixing the ends of the pipe to the fuel-filling inlet and the fuel tank respectively.

16. A pipe according to claim 15, in which the tubular section is at least partially of bellows form to render it longitudinally flexible.

17. A pipe according to claim 15 or 16, in which each fixture means is a releasable clip-type fitting.

18. A pipe according to any one of claims 15 to 17, in which the material of the tubular section is thermoplastic material.

19. A pipe according to any one of claims 15 to 18, in which the fire-resistant material is rubber.

20. A pipe substantially as herein described with reference to the accompanying diagrammatic drawings.