WO1989003330A1

WO1989003330A1 - Vehicle antitheft fuel valve lock

Info

Publication number: WO1989003330A1
Application number: PCT/AU1988/000399
Authority: WO
Inventors: Barry Penfold; Raymond Coward
Original assignee: PETROLOK ENTERPRISES Pty Ltd
Current assignee: PETROLOK ENTERPRISES Pty Ltd
Priority date: 1987-10-14
Filing date: 1988-10-14
Publication date: 1989-04-20
Anticipated expiration: 1990-04-14

Abstract

A lockable fuel valve with a body (1), fuel inlet port (14), fuel outlet port (15), fuel return port (2), all entering a blind bore hole (11) of the body (1), and a piston valve (5) telescopically sliding within the bore hole (11). The bore hole (11) and piston valve (5) have respective cut away portions and ''O''-ring seals (25) so that in a closed position the fluid flow path from the inlet port (14) extends to the return port (2) and is closed off from the outlet port (15) while in an open position the flow path extends from the inlet port (14) to the outlet port (15). The piston valve (5) is moved in one direction by the resilient spring (17) and into the opposite locked position by a lockable plunger (18). The plunger (18) is screwed to the body (1) and attached to the underside of the floor of the vehicle proximate the driver's seat so that the plunger (18) can be depressed by the driver's foot so as to be locked in the ''off'' position without the need to insert the key. The plunger (18) is then unlocked by the normal insertion and turning of the key. The inlet port (14) is connected to the fuel supply line from the petrol tank, the outlet port (15) to the fuel supply line leading to the engine and the return port (2), in the case of fuel injection vehicles, is connected to a return line to the fuel tank and, in the case of non-fuel injected vehicles, is plugged off.

Description

"VEHICLE ANTI THEFT FUEL VALVE LOCK" BACKGROUND ART This invention relates to devices for combatting motor vehicle theft. In particular this invention provides a lockable fuel valve for use in vehicles in order to reduce the possibility of theft of the vehicle.

PRIOR ART Certainly many different types of theft deterrents and/or theft preventive devices have been used in the past. Although most of the previously known devices have worked at least to some degree, none are perfect.

This invention therefore provides a further alternative theft prevention device.

BROAD DESCRIPTION OF THE INVENTION In one broad form the present invention can be said to consist in a lockable fuel valve comprising : a body with a bore hole therein; an inlet port and an outlet port each entering the bore hole from the exterior of the body and each including a respective attachment means adapted to sealingly receive a respective fuel line; a piston valve within the bore hole being moveable between a first position and a second position wherein the piston being in the first position allows fluid flow from the inlet to the outlet ports while the piston being in the second position substantially prevents said fluid flow; and a lockable plunger actuable so as to move the piston from the first position into the second position and provide automatic locking of the piston in the second position and being unlockable so as to allow the return of the piston into the first position.

Preferably the bore hole and piston valve are cylindrical and of close sliding telescopic fit, the piston entering one open end of the bore hole opposite a second blind end. It is further preferred that the piston valve is biased away from the blind end of the bore hole and that the lockable plunger is coaxial with the bore hole and attached to the body at the open end of the bore hole, the plunger also being biased away from the blind end of the bore hole.

Preferably the body includes a fuel return port entering the bore hole from the exterior, the inlet port being positioned longitudinally of the bore hole intermediate the outlet port and the return port and therebeing annular seals between the piston valve and the bore hole periphery such that when the piston valve is in the closed positioned the inlet port and return port are in fluid communication. This preferred feature is well adapted for units used in fuel injection vehicles which pump fuel to an injector unit and return surplus to the fuel tank. Thus, the fuel lock must allow for the circulation of fuel whenever the rear fuel pump of the vehicle is actuated.

Preferably the attachment means of the inlet and outlet ports are threaded holes.

BRIEF DESCRIPTION OF THE DRAWINGS By way of example only, two preferred embodiments of the invention will now be described with reference to the accompanying drawings which show: Pig« being a partially sectioned exploded perspective view of a valve embodying the invention;

Fig. 2 being a similar view of another valve embodying the invention in an alternative arrangement; Fig. 3 is a sectional elevation of the embodiment when in one configuration; and

Fig. 4 is similar to Fig. 3 but with the device in an alternative configuration.

DESCRIPTION OF PREFERRED EMBODIMENTS The valve of Fig. 1 includes a body 10 of generally cylindrical shape and including a coaxial cylindrical bore hole 11. The bore hole 11 is open at one end and blind at the opposite end. Proximate the blind end of the bore hole 11 is an annular step 12, at which the diameter of the bore hole 11 reduces. An "0"-ring 13 is lightly frictionally positioned at the step 12. On one axial side of the step 12 an inlet port 14, formed as a tapped hole through the body 10, enters the bore hole 11. A similar outlet port 15 enters the bore hole 11 on the opposite axial side of the step 12. A cylindrical piston valve 16 is provided for a close but sliding fit within the bore hole 11 and includes an annular seal between the piston 16 and bore hole 11. When the piston 16 is slid fully home towards the step 12, the annular outer surface of the proximate end face of the piston 16 seals against the "0"-ring 13 which in turn seals against the step 12. Thus when the piston 16 is fully home there is provided a positive fluid seal between the inlet and outlet ports 14 and 15 respectively. The seal 25 is positioned axially on the side of the inlet port 14 opposite the step 12 so as to seal off the fluid path from the exterior of the valve. A resilient spring 17 is positioned within the smaller diametric portion of the bore hole 11. Spring 17 is of sufficient length to urge the piston 16 away from the step 12 and substantially clear of the inlet port 14, thus providing clear fluid flow from the inlet port 14 to the outlet port 15.

In order to control the movement of the piston 16 there is provided a lockable plunger 18. The plunger 18 includes an outer sleeve 19, an inner sleeve 20, and a base plate 21 rigidly attached to the outer sleeve 19.

The base plate 21 includes a lower surface which matingly engages a corresponding upper surface of the body 10. These two surfaces sealingly engage by virtue of the "0"-ring 26. The plate 21 is held in place by screws 22 which threadedly engage holes 23 of the body 10. Co-operative with the screws 22 are respective spacers 24 which allow installation of the lock rigidly attached to, but spaced from, any planar surface such as the floor of a motor vehicle. Of course suitable washers are advantageously used between the heads of the screws 22 and the spaces 24.

The inner sleeve 20 includes a suitable locking mechanism which engages when the inner sleeve 20 is depressed fully home within the outer sleeve 19. The inner sleeve 20 extends axially through the outer sleeve 19 sufficiently to engage the piston 16 so that depressing the inner sleeve 20 fully home to the locked position pushes the piston 16 into the above described sealing engagement with the "0"-ring 13 and step 12. The locked plunger 18 is released by using the correct co-operative key, allowing the inner sleeve 20 to retract from the outer sleeve 19, in turn allowing the return of the piston 16 to its first open position distant from the blind end of the bore hole 11. Preferably the lock is positioned in the floor of the vehicle a small distance in front of the driver's seat. When leaving the vehicle the driver merely presses down on the inner sleeve 20 of the plunger, without needing to manipulate the lock with the key, in order to lock the fuel valve. This is conveniently done by the heel of the driver's shoe.

Upon re-entering the car the fuel lock is open by use of the corresponding key.

The materials and clearances in the lock are selected so that it is suitable for petrol, diesel and LPG fuels. Further, the keyed lock is of an "unpickable" design.

An alternative design is shown in Fig. 2. The device is similar to that shown in Fig. 1 in that it includes a piston valve 5 in sliding fit within a bore hole 11 of a valve body 1 so as to control fluid communication between the inlet port 14 and the outlet port 15. The piston valve 5 is biased by spring 17 away from the blind end of the bore hole 11 and the lockable plunger 18 is attached by screws 22 to the body 1 and sealed by the "0"-ring 26 which seats between mating faces of the plunger 18 and the body 1.

However, in addition body 1 includes a return port 2 proximate the blind end of the bore hole 11 and the piston valve 5 includes three "0"-rings 25. The fuel supply line of the vehicle leading from the fuel tank to the engine fuel metering device (perhaps a carburettor or fuel injection unit) is cut at a convenient point proximate the fuel lock. The fuel tank side is connected to the inlet port 14 and the engine side to the outlet port 15. On vehicles with pressured fuel delivery from the fuel tank (such as fuel injected vehicles) the return port 2 is connected into the fuel return line intermediate the engine and the fuel tank, otherwise it is plugged off.

Operation is best described with reference to Figs. 3 and 4. When locked off as shown in Fig. 3 the fuel flow path 27 leads from the inlet port 14 to the return port 2, the outlet port 15 being isolated by the intermediate "0"-ring 25. When the lockable plunger 18 is released the spring 17 moves the piston valve 5 into the "on" position shown in Fig. 4 so as to form a fluid flow path 28 from the inlet port 14 to the outlet port 15. The return port 2 and the open end of the bore hole 11 are sealed by respective "0"-rings 25.

Claims

CLAIMS : -

1. A lockable fuel valve comprising: a body with a bore hole therein; an inlet port and an outlet port, each entering the bore hole from the exterior of the body and each including a respective attachment means adapted to sealingly receive a respective fuel line; a piston valve within the bore hole being movable between a first position and a second position wherein the piston being in the first position allows fluid flow from the inlet to the outlet ports while the piston being in the second position substantially prevents said fluid flow; and a lockable plunger actuable so as to move the piston from the first position into the second position and provide automatic locking of the piston in the second position and being unlockable so as to allow the return of the piston into first position.

2. A lockable fuel valve as in claim 1 wherein the piston valve and bore hole are a close sliding telescopic fit.

3. A lockable fuel valve as in claim 2 wherein the piston valve and bore hole are cylindrical and the piston valve is spring biased away from a blind end of the bore hole towards the lockable plunger being rigidly attached to the body coaxially of the bore hole at an open end thereof opposite the blind end.

4. A lockable fuel valve as in claim 3 wherein the piston valve includes longitudinally spaced apart respective annular "0"-rings about its periphery each being sized and positioned so as to provide a fluid seal between the piston valve and at least portions of the surface of the bore hole.

5. A lockable fuel valve as in claim 4 wherein the

"0" -rings are positioned so as to define fluid flow paths between the inlet port and outlet port when the piston valve is in the first position but not when in the second position .

6. A lockable fuel valve as in claim 3 wherein the body further includes a return port entering the bore hole from the exterior of the body such that the inlet port is positioned longitudinally of the bore hole intermediate the outlet port and return port, and the piston valve further includes longitudinally spaced annular seals providing fluid tight seal between the piston valve and at least parts of the peripheral surface of the bore hole so as to define, when the piston valve is in the first position, a fluid flow path from the inlet port to the outlet port and, when the piston valve is in a second position, a fluid flow path from the inlet port to the return port.

7. A vehicle including a lockable fuel valve as in claim 6 wherein the valve is positioned closely in front of the driver's seat of the vehicle such that the lockable plunger may be actuated by the driver's foot so as to move the piston from the first position into the second position and to automatically lock the piston into the second position.