GB2299614A

GB2299614A - Hydraulic or pneumatic gear, steering and brake locking system actuated by cam studs on the lock barrel causing rocker arms to open or close valves.

Info

Publication number: GB2299614A
Application number: GB9606459A
Authority: GB
Inventors: John Harris
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-04-05
Filing date: 1996-03-27
Publication date: 1996-10-09
Anticipated expiration: 2016-03-27
Also published as: GB2299614B; GB9606459D0

Abstract

The anti-theft device comprises an ignition switch in the form of a radial pin lock which has camming studs 14, 15 mounted at 90{ to each other on a rotatable barrel 12. The studs operate pilot valves 20, 21 through rocker arms 16, 17 which act as cam followers, and are arranged such that only one rocker arm is engaged at a time as the barrel rotates. When valve 20 is actuated, hydraulic or pneumatic pressure is applied to one side of the steering ram 29 and to cylinders 32, 33 operating a pneumatic gear selector, thereby preventing steering and gear selection. A parking brake lock is biased to be engaged when the ignition is switched off and no pressure is applied from valve 21.

Description

IGNITION SECURITY DEVICE This invention relates to an ignition security device, principally but not exclusively for use with commercial goods vehicles and public service vehicles.

A wide range of security devices have been proposed, and many of them put into use, for preventing the theft, or taking and driving away of motor vehicles, from private automobiles to heavy goods vehicles. These range from mechanical devices which are lockable into place to obstruct the operation of controls such as any one or more of the vehicle handbrake, clutch pedal, or steering wheel. Also used are electronic overrides for door and ignition locks. Generally speaking, such devices suffice to deter opportunistic theft, but can be overcome given time and a suitable lock-pick, or a metal saw to cut through metal parts.

Other types of eg steering lock, which lock the steering wheels in the straight ahead position, can be overcome by hitching the vehicle to tow-truck to run on the steering wheels, which are usually underdrive and thus free-wheel even if the geartrain to the drive wheels is locked into gear.

An object of this invention is to provide an ignition security device which by means of a simple lockable switch serves to immobilise at least the vehicle gear train, and the braking mechanism.

The present invention provides and ignition security device comprising a rotatable member arranged to be turned through a predetermined arc by operation of an ignition lock, said spindle carrying a radially extending cam member which is rotated through said predetermined arc by turning of the spindle, a control means being located at each end of arch turned by the member, each control means having an actuator means operable by the cam member, whereby one control means is actuated and the other unactuated, in each of the respective end positions of the cam member.

The control means preferably comprise hydraulic or pneumatic pilot valves, or electrical switches connected to in turn control valves or other slaved controls.

The lock is preferably a radial pin lock, which uses a tubular key with inwardly directed lock operating detents. Copies of such keys are not obtainable from locksmiths or other retailers.

The control means have actuators, such as rocking levers be located respectively at the ends of a 90 degree or quadrant arc, for example 9 o'clock and 12 o'clock positions, to be alternatively engaged by the cam members, one in the lock 'on' position and the other, after turning the lock through a right angle in the lock 'ofF position.

It will be appreciated that further cam means, at 180 degrees to the cam means, can be mounted in the barrel, for cooperation with further control means, such as a further pair occupying the other two quadrants (3 o'clock and 6 o'clock). These may be pilot valves or electrical switches as desired.

In a preferred embodiment one of the control means may be arranged to control a pneumatic braking circuit, and is embodied as a pilot valve, having a valve closure member operable against a spring, by a push button which is depressed by a rocking lever when the associated cam means is in the ignition off position (ie locked to immobilise the vehicle) to open the pilot valve and thereby lock the steering in position under fluid pressure, in the extreme right or left lock, with the pressure acting to maintain the steering rams in the full lock position.

The circuit controlled by the said one of the control means may also be connected to the gearbox, with pressure being applied to the auto-select so that gears cannot be selected, gear selection signals being blocked by the application of maximum pressure to the autoselector.

The other of said control means is preferably also a pilot valve which is operated by a rocking arm/cam means of the lock barrel is in the alternative (unlocked) position.

This pilot valve is held open by pressure of the rocking arm on the respective actuator, to apply pressure to a parking brake release device, which acts against a spring to release the brake to allow it to be operated normally.

The ignition switch operated by the lock barrel also preferably actuates an automatic vehicle security alarm. This preferably includes a motion sensor which senses the presence of a person on the control area, and arms the alarm when motion has ceased.

The alarm may when triggered initiate a low level response which allows a legitimate user a limited period to neutralise the alarm by turning the ignition, before moving to a full alarm condition, with audible and visual signals.

The cam means may preferably comprise a pair of risers located on a rotatable barrel member, and disposed at 90" intervals, to engage with first ends of rocker arms, the other ends of which can depress respective valve actuators.

When the pilot valve is closed, as the lock is changed over to the lockable position the pressure is released, and the spring locks the parking brake closed against release.

The lock barrel itself also locks the vehicle ignition switch.

A preferred embodiment of ignition security device according to the invention will now be described, by way of example, with reference to the accompanying drawings wherein: - Fig 1 is a block diagram of the ignition lock system, and the circuits controlled by associated control means; Fig 2 is a view from above of a lock-and-valve assembly which forms an important part of the ignition security device; Fig 3 is a vertical sectional view, on line III-III of Fig 2 of the assembly of Fig 2; Fig 4 is an end view of the assembly of Figs 2 and 3, from the right, as viewed in the drawings; Fig 5 is an end view of the assembly of Figs 2 and 3, from the left, as viewed in the drawings;; Fig 6 a-6 are a sequence of diagrammatic views showing the operation of a rotatable barrel and rocker bars operating pneumatic control valves, forming part of the apparatus, and Fig 7 is a cross-sectional view of a pneumatic coaxial tubing used in the ignition lock system according to the invention.

An ignition security lock according lock according to the invention includes a lock barrel 10, with an annular slot 11, for a key and is constituted by a radial ten-pin lock.

The operation of the lock turns a barrel 12 through 90 degrees (a quadrant) between locked and unlocked positions, and operated an ignition switch 13 (Figs 2 and 3). the barrell 12 carries a pair of cams, 14, 15, in the form of two risers, such as rivit or bolt heads, disposed at 90" angle on the barrel, which when the barrel 12 is rotated by turning the key, moves through an arc of 90 degrees, eg from a locked position to an unlocked position.

A pair of rocker bars 16, 17, pivoted mid-way along their length, act as cam-followers and their respective other ends engage on push button type operating members 18, 19 of pilot valves 20, 21, the members 18, 19 being biased into an extended position by spring means (not shown) and are adapted to be pushed inwardly when the respective rocker bar 16 or 17 is tilted by the respective cam 14, 15.

The pilot valves 20, 21 are of the normally closed type, the valves being closed when the members 18, 19 are extended, and opened by depression of the respective member by the respective rocker bar.

In the 'on' or locked state of the ignition lock, the bar 16 is as shown in Fig 1, maintaining pilot valve 20 open. At the same time pilot valve 21 is closed, since rocker bar 17 is not shown in a position to depress the operating member 17. In the locked state, the reverse is true and whilst valve 20 is closed, no pneumatic pressure is admitted to lines 22, 23 and the steering and gear selection are operable as normal. At the same time, valve 21 is open, and pressure is applied via line 24 to a cylinder 25, with a plunger 26. Whilst pressure is applied, plunger 26 is depressed against a spring 27, and a brake lock 28 is kept disengaged. this pneumatic circuit could be replaced by an electrical circuit, controlled by a switch in place of valve 20, operating a solenoid the plunger of which replaces plunger 26.

When lock 10 is applied and the barrel 12 turned 90 degrees anticlockwise, the cams 14, 15 rotate through 90 degrees. Valve 20 allows pressure to be introduced to steering apparatus, eg a ram 29, via line 22, and if tull right or left steering is first applied, the pressure of this fluid behind the ram plunger, which is in the extreme position as shown, prevents actuation of the steering ram by the normal fluid connections 30, 31. Pressure in also applied via line 23 to operate a master cylinder 32, which operates a slave valve 33 in a pneumatic airline 34 connected to both sides of a cylinder 35 which operates a gear selector. The pressure applied via line 34 is sufficiently high to prevent operation of cylinder 35 by the normal inlets 36, 37 by overriding and buffering out any signals applied.Figs 6a-6d illustrate a sequence of operations of the valves 20, 21 as the rotated.

The simultaneous closure of valve 21 cuts off the supply of pressure medium to cylinder 25, and the spring 27 moves the plunger 26 upwards, applying the brake lock 28.

Fig 7 shows a cross-section through a co-axial pneumatic tubing which can be used for simultaneous transmission of fluid pressure signals to and from the valves of two signals in opposite directions, which thereby increases flexibility, and reduces the number of tubes needed in a pneumatic system.

So long as the lock is in the locked position, the steering will be positively locked in either of the tull-lock positions, the gear train will be immobilised by the gear selector being inoperative and the park brake will be locked on by the fail safe spring 27 and the ignition switch will be locked in the off position.

The ignition switch operated by the ignition lock also controls an automatic vehicle alarm circuit, so that switching the ignition off, and initiating the locks will also set the alarm. The alarm apparatus includes a sensor which can detect movement in the control cab area, and will arm the alarm when no motion has been detected, thus allowing the driver to leave the vehicle, or retire to a sleeping compartment. When an intrusion is detected a warning signal is given for a short period to allow the legitimate driver to operate the ignition switch, and turn the alarm off At the end of this period the alarm will initiate a full alarm with visual and audible signals. This will enable a driver to use the sleeping compartment with the alarm active. Also windows may be left open with this arrangement.

The above description is an outline only, and in practice the hydraulic and pneumatic circuits will contain all the normally required safety and regulatory features, and other means may be adopted within the scope of the invention. For example, the cam could actuate electrical switches arranged to control the steering and gear selector circuits, and the parking brake, without bringing hydraulic lines into the control area, using for example solenoid or electromagnetic valves to control fluid circuits.

By providing more cams on the lock spindle, more functions may be controlled by the operation of the ignition lock and the control means operable by the cams may be a combination of electrical switches and hydraulic or pneumatic valves.

Such possible further functions include the locking of power steering using the switch, in cars and other light vehicles as well as in trucks and the like, also the operation of the clutch may be controlled by the apparatus.

The supply of pressurised air to buffer out gear change signals is suitable for one type of gear change mechanism, exemplified by the Volvo 'Geartronic' gear box. Other types of gearbox may require other measures to block their operation such as the removal of fluid or air pressure, and the operation of the control switches or circuits can be adjusted as required within the scope of the invention.

Further it is preferred that the fuel supply - such as an electronic diesel control - (or the fuel injection pump in the case of a light vehicle) be cut off by locking the ignition switch lock according to the invention.

The ignition switch and its associated pilot valves and pneumatic coaxial tubing is securely mounted in a tamper proof housing in a vehicle control panel, so that access is only possible through using the correct key. Unlike yale or mortice keys, radial pin keys cannot be copied by retail locksmiths and are very secure against picking.

Claims

1. An ignition security device comprising a rotatable member arranged to be turned through a predetermined arc by operation of an ignition lock, said spindle carrying a radially extending cam member which is rotated through said predetermined arc by turning of the spindle, a control means being located at each end of the arc turned by the cam members, each control means having an actuator means operable by the cam member whereby one control means is actuated and the other unactuated, in each of the respective end positions of the cam member.

2. A device according to claim 1 wherein the control means comprise hydraulic or pneumatic pilot valves, or electrical switches connected to in turn control valves or other slaved controls.

3. A device according to claim 1 or 2 wherein the lock is a radial pin lock with a tubular key with inwardly directed lock operating detents.

4. A device according to claim 1, 2 or 3 wherein the control means have actuations which are spaced through 90 with respect to the rotatable member to be alternatively engaged by cam members, one in the lock 'on' position and the other after turning the lock through a right angle in the lock 'off position.

5. A devise according to any preceding claim wherein one of the control means is arranged to control a hydraulic steering circuit, and comprises a pilot valve having a valve member operable against a spring by a push button which is depressed by a rocking lever when the associated cam means is in the ignition off position, to open the pilot valve and thereby lock the steering in position under fluid pressure.

6. Advise according to claim 5 wherein one of the control means is also connected to the gearbox with pressure being applied to the autoselect so that gears cannot be selected, gear selection signals being blocked by the application of maximum pressure to the autoselecter.

7. A device according to claim 5 wherein the other of said control means is preferably also a pilot valve which is operated by a rocking arm when the cam means of the lock barrel is in the alternative unlocked position, and is held open by the pressure of the rocking arm in the respective actuator, to apply pressure to a parking brake release devise, which acts against a spring to release the brake to allow it to be operated normally.

8. A device according to any preceding claim wherein the ignition switch operated by the lock barrel also actuates an automatic vehicle security alarm, which includes a motion sensor which senses the presence of a person in the control area to arm the alarm when motion has ceased.

9. An ignition security device substantially as here before described, with reference to and as illustrated in the accompanying drawings.