GB2251604A

GB2251604A - Venting device which prevents overfilling and spillage of fuel tank

Info

Publication number: GB2251604A
Application number: GB9123973A
Authority: GB
Inventors: Eric Deparis; Serge Percebois
Original assignee: TRANSFORMAT MAT PLASTIQUES; TRANSFORMATION DES MATIERES PLASTIQUES Ste
Current assignee: TRANSFORMAT MAT PLASTIQUES; TRANSFORMATION DES MATIERES PLASTIQUES Ste
Priority date: 1990-11-14
Filing date: 1991-11-12
Publication date: 1992-07-15
Anticipated expiration: 2011-11-12
Also published as: KR100233924B1; ES2049615B1; FR2668987A1; GB2251604B; FR2668987B1; ITMI913020A1; ITMI913020A0; NL9101891A; DE4137523A1; JPH0692151A; JP3238173B2; ES2049615R; ES2049615A2; GB9123973D0; IT1252394B; KR920009628A

Description

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Description

Fuel Supply System Safety Device This invention relates to a safety device for the system supplying the tank of a motor vehicle with fuel, simultaneously performing the functions of prevention of overfilling and of venting during use while preventing the discharge of fuel in use or in the case of an incident or accident in which the vehicle were to find itself in an inclined position.

At present, motor vehicle fuel tanks have to be fitted with a set of pipes and devices fulfilling separate functions, in particular an overfill prevention function and a function of venting during periods of use to allow air to enter and excess fuel vapour to escape. In addition, it is essential for the devices used to these ends to guarantee complete safety and, in particiilar. to prevent or minimise any discharge of fuel not only during normal use but also in the case of incidents or accidents involving a steep inclination or even overturning of the vehicle.

To achieve such a result. it is generally necessary to resort to a set of separate special devices. Thus, in European patent application EP 0 333 549, a device is disclosed for venting and for protecting against the overfilling of a tank which involves, on the one hand, the use of a vent pipe closing valve, and, on the other hand, the use of an independent safety valve providing ventilation and protection in the case of excessive inclination.

A single device has now been developed which performs the various functions necessary in order to guarantee correct operation and complete safety of the system for the supply of fuel to a motor vehicle tank.

This invention therefore relates to a safety device for the system supplying the tank of a motor is vehicle with fuel performing the functions of prevention of overfilling and of venting during use while preventing any discharge of fuel particularly in the case of an incident or accident comprising a closed chamber fitted with:

an inlet aperture set in its lower wall and connected by a pipe to a high point of a tank, an outlet aperture set in its upper wall and connected to a vent pipe, the two apertures being arranged on a single vertical axisi which Is characterised in that the closed chamber comprises a first control system enabling the inlet aperture to be sealed, during the filling of the tank, and a second control system enabling the outlet aperture to be sealed particularly in cases where the vehicle is inclined excessively.

According to a preferred embodiment, the first control system is constituted by a lever pivoting about a spindle, arranged inside the closed chamber, one end of which, onto which bears a control rod stressed by the tank sealing device, is provided with a compression spring tending to hold the control rod in a raised position and the other end of which supports by an appropriate circular opening a ball arranged in line with the inlet aperture, and the second control system is constituted, on the one hand, by a seating of tapered profile arranged inside the closed chamber in line with the inlet aperture and capable of receiving the ball and, on the other hand, by a valve needle also arranged inside the closed chamber and capable of sealing the output aperture, said valve needle being fitted with an attachment imprisoning the ball.

In the device according to the invention. the atta chment imprisoning the ball is preferably of rectangular section and its base comprises a circular opening, of diameter less than the diameter of the ball. arranged in line with the inlet aperture and designed to accommodate said ball.

A cutaway provided in the lateral wall of the is attachment allows the pivoting lever to pass through. In general. the lever arm comprising the circular opening is situated above the base of the attachment and the diameter of the circular opening provided in this lever arm is such that, with the lever arm and the attachment in the lowered position.. the wall of the ball is in simultaneous contact with the edge of this opening and with the edge of the circular opening provided in the base of the attachment.

Preferably, the diameter of the ball and the height of the attachment are dimensioned so that, with the lever arm supporting the ball in the raised position and with the attachment in the lowered position, the top of the ball is in contact with the upper wall of the attachment.

In the device according to the invention, when the tank is being filled, removal of the sealing device or any other mechanism releases the pressure normally exerted on the control rod and so leads to pivoting of the lever under the action of the compression spring with the result that the ball comes to rest, by gravity. on the inlet aperture which is thus sealed. The tightness of this seal is maintained so long as the pressure in the pipe connected to this aperture is insufficient to raise the ball. The weight of the ball,, generally of metal, should therefore be selected to be sufficient to prevent overfilling of the tank.

After filling of the tank, replacement of the sealing device or any other mechanism once again exerts a pressure on the control rod and so leads to pivoting of the lever in the opposite direction and compression of the compression spring resulting in raising of the ball which comes away from the inlet aperture and comes into contact with the upper wall of the attachment.

During normal use of the vehicle, the inlet and outlet apertures are therefore clear,, allowing air to enter the tank or fuel vapour to escape.

On the other hand, if the vehicle is inclined excessively, the ball is displaced by gravity along the seating provided in line with the inlet aperture and pushes the attachment upwards resulting in sealing of the outlet aperture by the valve needle. In the device according to the invention, it is additionally possible to dimension the circular openings provided in the base of the attachment and in the lever so as to steady the ball thus avoiding inadvertent sealing of the output aperture.

The safety device according to the invention is further clarified in the description which follows of a preferred embodiment, in which reference will be made to the single figure in the attached drawing which gives a sectional view of a safety device according to the invention.

As the figure shows, the safety device is constituted by a closed chamber 26, constructed in metal or plastic material, comprising, in its lower wall, an inlet aperture 15 connected by a pipe. not shown. to a high point of the tank and, in its upper wall, an outlet aperture 14 connected, by its neck 2, to a vent pipe. not shown, optionally fitted with a recovery canister. the two apertures being situated on a single vertical axis.

The closed chamber 26 is, in addition, fitted internally with a first control system 27 enabling the inlet aperture 15 to be sealed during filling of the tank and with a second control system 28 enabling the outlet aperture 14 to be sealed in particular if the vehicle is inclined excessively.

The first control system 27 comprises a lever 8 pivoting about a spindle 11 one of whose ends, on which rests a control rod 9 stressed by the tank sealing device 1, is provided with a compression spring 10 tending to hold the control rod 9 in a raised position,, and the other of whose ends supports, by a circular opening 13. a metal ball 7 arranged in line with the inlet aperture 15.

The second control device 28 is constituted. on the one hand, by a tapered seating arranged inside the closed chamber 26 in line with the inlet aperture and capable of receiving and guiding the ball 7 and, on the other hand. by a valve needle 4 also arranged inside the closed chamber and capable of sealing the output aperture 14, the said valve needle 4 being fitted with an attachment 5 imprisoning the ball 7. The attachment 5 is of rectangular section and Its lower wall comprises a circular opening 6 adapted to receive the ball 7.

The operation of the device described Is as follows% With the vehicle in normal use. the tank sealing device 1 exerts pressure on the control rod 9 which is communicated to the lever 8 the pivoting of which raises the ball 7 and moves it away from the inlet aperture 15. The raising of the ball 7 is such that the latter comes only into contact with the upper wall 18 of the attachment 5 which remains in the position shown in the f igure. a result of this being that the valve needle 4 remains clear of the outlet aperture 14. As the inlet and outlet apertures are unobstructed, air is allowed to pass into the tank or fuel vapour to escape.

If, on the other hand, in the case of an incident or accident, the vehicle becomes excessively inclined, the ball 7 disengages itself from the circular openings 6 and 13 and moves along the seating 12 consequently propelling the attachment 5 upwards and so sealing the outlet aperture 14 with the valve needle 4. As a result, accidental discharge of fuel is prevented by the closure of the outlet aperture 14.

During filling of the tank, removal of the tank sealing device 1 releases the control rod 9 and, under the action of the compression spring 10, the lever 8 pivots so that the ball 7 comes to seal. by gravity, the inlet aperture 15 and this prevents overfilling of the tank.

6 - It will be understood that the invention has been described above purely by way of example, and that various modifications of detail can be made within the ambit of the invention.

7

Claims

CLAIMS:

1. A fuel supply system safety device suitable for use in a system f or supplying a tank of a motor vehicle with fuel, performing the functions of overfilling prevention and of venting during use, while preventing discharge of fuel in the event of an incident or accident; the device comprising a closed chamber provided with an inlet aperture set in its lower wall and connected by a pipe to a high point of a tank, and also provided with an outlet aperture set in its upper wall and connected to a vent pipe, the two apertures being positioned substantially on a single vertical axis; wherein the closed chamber is additionally provided with a first control system enabling the inlet aperture to be sealed during the filling of the tank and with a second control system enabling the outlet aperture to be sealed in the event of the vehicle being inclined excessively.

2. A device according to Claim 1, wherein the f irst control system comprises a lever pivoting about a spindle mounted within the closed chamber; one end of the lever, against which bears a control rod stressed by a tank sealing device, being provided with a compression spring urging the control rod into a raised position; and the other end of the lever supporting, by means of a circular opening, a ball disposed substantially in line with the inlet aperture.

3. A device according to Claim 2, wherein the second control system comprises a seating of tapered profile disposed inside the closed chamber substantially in line with the inlet aperture and so designed and positioned as to be capable of receiving the ball, and also comprises a valve needle which is also disposed inside the closed chamber and which is so designed and positioned as to be capable of sealing the outlet aperture, said valve needle being provided with an attachment imprisoning the ball.

4. A device according to Claim 1, substantially as described with reference to the accompanying drawing.