GB2288451A

GB2288451A - A lockable valve

Info

Publication number: GB2288451A
Application number: GB9407390A
Authority: GB
Inventors: Benjamin Beveridge
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-04-14
Filing date: 1994-04-14
Publication date: 1995-10-18
Also published as: GB9407390D0

Abstract

Flow of a material through a valve is stopped by an electrical signal from outside the valve which operates a solenoid controlled trigger mechanism to disengage a plunger 14. Flow through the valve can only be resumed by actuating a key operated cam 13 which acts upon the plunger 14 to lift an obstruction 11, typically a ball, from an orifice seat 12 within the flow path of the material passing through the valve. The act of moving the plunger and displacing the flow obstruction, automatically engages the trigger mechanism to retain the valve in the open position until such time as a further electrical signal is sent to the solenoid to close the valve flow. The plunger 14 operates an electric switch 23 to provide a visual indication of when the valve is closed. The valve is particularly for use as a fuel cut-off device in a motor vehicle. <IMAGE>

Description

A VALVE CONTROL SYSTEM This invention relates to a valve control system and particularly, but not exclusively, to a lockable fuel valve.

According to one aspect of the present invention there is provided a valve control system for use in controlling a flow of fluid, having first means for causing actuation of a valve shutter thereof in a sense such as to inhibit flow of fluid through the valve, and second means for causing actuation of said valve shutter in a sense such as to allow flow of fluid through the valve, the said second means being operable only by an authorisation code or key.

A valve control system as defined above simplifies operation by a user since, in a first and preferred embodiment of the invention, the said first means may be located remotely from the valve itself. If, in a typical application, for example in which the valve is applied as a fuel cut-off valve in a motor vehicle, the said first means may be fitted on or near the dashboard to be accessible to the driver whereas the fuel cut-off valve may be located beneath the vehicle at an otherwise inaccessible location.

The said first means may be electrically, hydraulically or pneumatically operated and this is particularly convenient in the case of a remote operation as outlined above.

For use as a fuel cut-off valve in motor vehicles, it is preferable that the valve remains in its closed state after actuation and is designed so that it is physically impossible to open the valve without either a mechanical key or, if the valve may be opened electrically, hydraulically or pneumatically, the requirement for a suitable authorisation code. Mechanical operation is preferred, however, since it is considered to be more secure and less likely to be the subject of attempts to bypass the valve.

Preferably the system includes electrical switching means operable to cause energisation of an appropriate valvedisplacement member when an electrical circuit is either completed or opened. The valve-displacement member is preferably mechanically interconnected with a resiliently biased member associated with the lock such that, upon energisation of the valve-displacement member, the resiliently biased lock member is able to move from an inactive to an active position in which latter position it retains the valve in the closed state. The valve is now held closed mechanically, and only mechanical displacement of the resiliently biased member from its active towards its inactive position can result in opening of the valve: preferably the valve is resiliently biased to an open position.

In order to avoid inadvertent obstruction of the fuel supply line when the engine is in operation the electrical valve displacement means is preferably incorporated in a circuit with the ignition switch such that, when the ignition switch is closed the electrical valve-operation circuit is isolated.

One advantage of the control system of this invention is that it allows complete isolation of a vehicle engine from the source of fuel by means of an electro/mechanically operated lockable valve inserted into the fuel line which typically runs under the floor of the vehicle from the fuel tank to the engine. The fuel valve can only be closed by means of an electrically operated solenoid within the fuel valve and triggered by a remote switch and can only be opened by means of a key which is inserted into the fuel valve, typically into the body of the lock which projects through the floor of the vehicle to activate the fuel lock which is secured outside the vehicle under the floor.

One embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a schematic view illustrating a typical installation on a passenger car; Figure 2 is a sectioned plan view of the fuel valve in the closed position; Figure 3 is a sectioned plan view of the fuel valve in the open position; Figure 4 is a sectioned side view of the fuel valve in the opened position; Figure 5 is a schematic diagram of a typical electrical operating circuit for the fuel valve operation; Figure 6 is an enlarged detail of the embodiment illustrated in Figures 2, 3 and 4 showing the working parts in a first working position; and Figure 7 is an enlarged detail, similar to Figure 6, showing the compound parts in a second working position.

Referring to the drawings, Figure 1 shows a typical installation on a motor vehicle where 1 is the fuel tank, 2 represents the engine fuel injection system or carburettor and 3 shows the fuel line connecting the fuel tank to the engine. 4 represents the lockable fuel valve located under the floor 5 where it can be opened by the key 6 and closed by the electrical switch 7.

Figures 2 and 6 show a sectioned plan view of the fuel valve where 8 is the body of the valve into which fuel enters at 9 and leaves, when the valve is in the open position, at 10. Fuel is prevented from passing through the body of the valve from 9 to 10 by a spring-loaded ball 11 forced against a sear 12. The only means of lifting the spring-loaded ball from the seat, is for the cam 13, which is spring-loaded to return to the closed position as shown, to be rotated clock-wise (as seen in the drawing) from the closed position and thus bearing against the plunger 14 which will, in turn, lift the ball from the seat 12 and allow fuel to flow through the valve. The plunger 14 is equipped with a seal to prevent fuel from leaking from the passage from the entry 9 to the exit 10.

Figures 3 and 7 show a sectioned plan view of the fuel valve in the open position where fuel is free to flow from the entry 9, through the body f the valve 8, past the ball 11 and leave the valve at the exit 10. When the cam 13, which is operated by the key and lock, is rotated to bear against the plunger 14 and thus lift the ball 11 from the seat 12, a trigger pin 16 is forced into a groove 17 machined into the plunger 14 by the action of a spring 18 pulling the piston 19 from the solenoid housing 20.

The action of the piston being pulled from the housing reacts on the trigger pin 16 by way of a pivoted link 21 which is connected to the trigger pin 16 by way of a pivoted link 21 which is connected to the trigger pin 16 which has roller wheels 22 at each end to allow a rolling contact between the trigger pin 16 and the body of the lock as the trigger pin is moved relative to the plunger 14 by the action of the solenoid 20 or the spring 18.

When the solenoid piston 19 is withdrawn from the solenoid 20 by the action of the spring 18 and the trigger pin is engaged with the groove 17 in the plunger 14, the valve is held in the open position allowing the free flow of fuel through the valve.

When the solenoid 20 is energised, the pistol 19 is drawn into the solenoid housing which, in turn, draws the trigger pin 16 out of the plunger groove 17 and allows the spring-loaded plunger 14 to retract toward the cam 13 and the ball 11 to be forced against the seat 12 so stopping the flow of fuel. the plunger, when retracted allowing the valve to close, also acts on a probe connected to a switch 23 which can complete a circuit to permit a warning light to be illuminated to warn that the valve is closed.

Figure 4 shows a sectioned side view of the fuel valve where the lock 24, which is operated by the key 25, is directly connected to the cam 13 which in turn bears against the plunger 14 to open the valve by pushing the closing ball 11 off its sear 12 and so allows the trigger pin 16 to engage with the groove 17 in the plunger to hold the valve open after the spring loaded cam has returned to the start position. The body of the valve 8 is secured to the underside of the vehicle floor, or similar concealed location, by bolts 26 and by a nut 27 threaded to the outside of the lock body 24.

Figure 5 shows a schematic circuit diagram of the operating functions of the fuel valve where 20 is the solenoid which can only be energised by the push-button switch 7 when the vehicle ignition or master switch 28 is in the 'OFF' position. when the switch 28 is closed the relay 29 disconnects power to the solenoid preventing accidental closing of the fuel valve while the vehicle is in motion. The switch 23 is linked to the position of the plunger 14 so that it will only be closed when the plunger is in the valve closed position which allows a warning light 30 to be illuminated to indicate that the fuel valve is shut off and the engine will not run. This circuit can also be integrated with any other alarm systems.

In other embodiments of the invention (not shown) there may be incorporated a timer circuit to allow a delay from the moment the switch 7 is engaged until the operation of the solenoid which shuts off the valve.

In another embodiment (not shown) a further circuit (that is in addition to the delay circuit) may be provided which intercepts the signal to the fuel gage to show "empty" when the valve is closed. In order further to confuse a potential vehicle thief into believing that the vehicle is out of fuel when the engine stops.

Claims

CLAIMS.

1. A valve control system incorporated within a housing or body such that the flow of material through the body of the valve can be stopped by means of.an electrically operated trigger mechanism allowing the valve to close but so arranged that the only way of allowing the flow of material to resume through the valve is by means of a lock protected mechanical operation.

2. A valve control system as claimed in Claim 1 wherein the flow of material through the valve is stopped by spring operated ball or other device seating into an orifice within the material flow path.

3. A valve control system as claimed in Claims 1 & 2 wherein the spring operated ball or other device can only be lifted from the orifice by means of a cam or lever operating through a rod or plunger thereby allowing the flow of material through the valve to continue.

4. A valve control system as previously claimed wherein the cam operated rod or plunger may be retained in the valve open position by means of a mechanical trigger mechanism such that the cam is no longer required to maintain the valve in the open position once the trigger mechanism has engaged with the rod or plunger to keep the spring operated ball or other device lifted from the orifice seat within material flow path.

5. A valve control system as claimed within Claims 1 to 4 wherein the only way of operating the cam which is the only way to open the valve is by way of a removeable key inserted from outside the valve control system into a lock within the valve control system and directly connected to the cam.

6. A valve control system as claimed in Claims 1 to 5 wherein the trigger mechanism which engages with the cam operated rod or plunger to maintain the valve in the open position can only be tripped to allow the valve to close by means of an electrically operated solenoid within the body of the valve.

7. A valve control system as claimed in Claim 6 wherein the means for closing the valve are completely contained within the body or housing of the valve except for the necessary electrical connections to an outside switch and power source.

8- A valve control system as claimed in Claim 5 wherein the means of opening the valve to allow flow through the valve are entirely mechanical and contained within the secure casing of the valve and valve lock except for an external key which is required to operate the valve opening mechanism.

9. A valve control system as claimed in Claims 1, 6 & 7 wherein the position of the rod or plunger can be described by means of an electrical contact which can be incorporated into the external electrical circuit to indicate whether the valve control system is open or closed.

10. A valve control system as claimed in Claim 9 wherein the external operating electrical circuit can incorporate warning lights,.alarm systems, time delays, operating switches and other electrical systems as required.

A valve control system substantially as described herein with reference to Figures 1 to 7 of the accompanying drawings