GB2305967A

GB2305967A - Lockable vehicle exhaust pipe closure

Info

Publication number: GB2305967A
Application number: GB9509908A
Authority: GB
Inventors: Hubert Joseph Flynn
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-05-16
Filing date: 1995-05-16
Publication date: 1997-04-23
Also published as: GB9509908D0

Abstract

A tube 1 fits over the end of the exhaust pipe 10 and locks onto a pin 9 fixed through the exhaust pipe. A rod 5 is rotated by a spring 11 due to engagement of a pin 12 in a channel in a guide sleeve 6, when a barrel lock 2 is operated, to engage the pin 9 in a channel in the rod. The device is stored on a bracket (14, Figs. 2 and 3) which mounts a pipe of similiar diameter to the exhaust pipe associated with a switch (15, 16) in the vehicle's ignition system which is closed when the device is stored.

Description

VEHICLE IMMOBILISATION DMICE This invention relates to a device which can immobilise a motor vehicle by causing an obstruction to the flow of combustion products when one attempts to start the engine but, in particular,it is a bifunctional device in that once it is fitted to the end of an engine's exhaust pipe the very act of removing the device from its stowed position in the vehicle immediately switches off the power to the ignition system. Various examples of devices which have been developed to immobilise vehicles by exhaust pipe obstruction are to be found in the prior art but all suffer fro the disadvantage that some sort of skilled work has to be done to the end srf- aces of the vehicle's existing exhaust pipe before the choking device can be fitted.

or example in G.B.S,186,911 there is taught a device which can only be fitted by having the existing exhaust pipe end rolled to produce one or more inwardly locating fortnations and this is certainly a machine shop operation. Again in G.3.2,193,531 device is described which fits over the end of the existing exhaust pipe and fixes to it with an exhaust clamp which is held by a hig:r tensile bolt with a dished end which shears off en fully tightened. This device also contains an internal seal ing member which does not seal until gases flow ir the system.In PCT/G393/00307 a device is described which can only be fitted to n exhaust pipe once a collier is fitted and this entails the use of threaded grub screws in the exhaust pipe itself.

inally in S. TJ. 1652135 a device can only be fitted once a collar is welded to the end of the exhaust pipe. There is a need therefore for a device to immobilise a vehicle which can be easily fitted to,and easily removed from, the end of an exhaust pipe without the requirement of any implement other than those to be found in the home garage. Such a device is the subject of the present invention and it excells over the prior art in that it is bifunctional and not only chokes the exhaust system but the act of removing it from its stowage holder in the vehicle actually cuts-out the power to the engine's ignition system.According to the present invention there is provided a vehicle imnobilisation device comprising a cylinderical body which fits over the end of the vehicle's exhaust pipe and locks to a diametrically disposed metal rod which has previously been passed through the exhaust pipe and which thereafter can only be removed by the use of a barrel lock member,with key, situated at the end of the cylinderical body and where the internal locking member which engages the rod is spring loaded so that with the key in position in the lock the device is set so that when the unit is pushed over the exhaust pipe the internal locking member irpacts the metal rod and rotates,under the action of the spring,to embrace the rod in a locking mode and where such a mode is only reversed by the use of the key in the barrel lock which back-rotates the locking member,re-sets the s r- ing,and allows the device to be withdrawn from the end of the exhaust pl?e ,afterwhlch it can be pushed into a stow-aay holrsing,located anywhere in the vehicle,where the act of pushing it into the housing and removing the key locks it in position and at the same time actuates a micro-switch whichrestores the power to the vehicle's ignition system. A specific embodrent of the invention will now be described bv way of example with reference to the accompanying drawings in which: Figure.l. is a diagramatic sectional side elevation of the vehicle immobilisation device.

Figure.2. is a diagramatic sectional side elevation of the device's stowage housing with the end of the device proceeding into place and pushing forward the plunger of a microswitch.

Figure.3. is a diagramatic sectional side elevation of the device's stowage housing with the end of the device proceeding into place and pushing upwards the toggle of the microswitch.

Figure.4. is a diagram of the front insertion end of the device showing how the mouth has been shaped so as to align the device for correct contact with the exhaust pin and how cover domes are provided to protect the emergent ends of the exhaust pin from knock-out by would-be thieves.

Figure.5. is a diagramatic sectional side elevation of a second embodiment of the vehicle immobilisation device which has no externally visible screws or rivets and supports the locking mechanism within a shaped solid block of material at the key end of the device.

Referring to the drawings the vehicle immobilisation device comprises a hollow cylindrical bosy 1 which is closed at one end by a locking mechanism 2,with its key 3,and open at the other end so as to present a pipr-like orifice 4 which can be slipped over ,in a telescopic manner, the metal end of a vehicle's exhaust pipe.

Within the cylinderical body 1 there is fitted a rod 5 which is rotatable within a metal sleeve 6 which is held in a central position by being welded to a disc 7 which is held in place within the cylinderical body 1 by means of the screws or rivets 8. This rod 5 has two Shaped channels machined out of its front end and it is these channels which impact and engage the solid rod 9 of the exhaust pipe 10 and wrap around it under the rwisting action of the helical spring 11 in order to achieve a locking bond. One end of the rotatable rod 5 carries a stud 12 which runs in an Shaped channel cut in the sleeve 6 and this gives a movement to the rod which is similiar to the forward and rotating movement which occurs when an electric lamp is inserted into a bayonet cap fitting.When the device is held in one hand and the key 3 is turned and pushed inwards with the other,in a manner of a lamp being inserted into a bayonet cap bulb holder,the spring's forward action throws the stud 12 into its most forward position in its Shaped channel and this puts the rod 5 into its "set" position and the key 3 cannot now be removed from the lock 2. When the "set" device is now pushed over an exhaust pipe end,which had previously been fitted with a solid through-rod 9,the rod 9 and the rod 5 impact and the rod 5 is forced inwards and at the same time rotates because its stud 12 moves to the top of one limb of the Shaped channel and immediately rotates to the end of the other Climb under the twisting action of the spring 11. This impact, with twisting,locks the two rods together and with the spring 11 now out of tension the key 3 can be removed from the lock 2 and the vehicle's exhaust system will be isolated from direct contact with the atmosphere because of the sealing ring 13 so the vehicle is therefore now immobilised. In order to facilitate the exact mating of the rods 9 and 5 the front of the device is shaped,as in Figure 4,and the channels(one shown dotted)lead the device into alignment with the emergent ends of the exhaust rod 9 and domes can be placed as part 17 to accomodate the emergent ends of the rod 9 and shield it from being knocked-out by would-be thieves.When the vehicle is not being immobilised by exhaust choking the device is stowed in a housing 14 in a convenient position within the vehicle where it is not conspicious and this housing, see Figures 2 and 3,receives the device in the same locking manner as is used when locking it to an exhaust pipe but in this case the action of stowing closes a microswitch 15 or 16 which is connected in series with the power line of the vehivle's ignition system. When the device is to be used to immobilise the vehicle it is withdrawn from its housing 14 by the use of the key 3 and this action firstly "sets" the device ready to be pushed over the end of the exhaust pipe and secondly the microswitch falls to its break mode and power is cut-off from the ignition syatem. The device therefore has a bifunctional protective role. Persons skilled in the art will realise that it is possible to vary the hardware necessary to choke the car's exhaust,for example,as in Figure 5 it is a simple matter to eliminate all external fixtures such as screws and rivets by fitting the key and spring loaded mechanism into a moulded or shaped block 18 which is permanently fixed in the cover 1 by pressure deformed dimples 19. Irrespective of these variations the basic innovation which will run through all versions is the locking of the device to an exhaust contained pin at an engine state where the ignition system is in open-circuit and the subsequent restoration of the ignition power when the device is later locked into its storage position.

Claims

ClAIMS

1.A vehicle immobilisation device comprises a cylinderical body which fits over the end of a vehicle's exhaust pipe and locks onto a diametrically disposed rod which has previously been fixed through the exhaust pipe and after which can only be removed using the key of a barrel lock member situated at the end of the cylinderical body and where the internal locking member,which engages the exhaust rod is spring loaded so that with the key in position in the lock the device is set so that when the unit is pushed over the end of the exhaust pipe the internal locking member impacts the rod and rotates,under the action of the spring,to embrace the rod in a locking mode and where such a mode is only reversed by the use of the key in the barrel lock which back-rotates the locking member,re-sets the spring,and allows the device to be withdrawn from the end of the exhaust pipe.

2.A vehicle immobilisation device according to Claim 1 wherein the spring-set device is pushed over a stow-away housing located in the vehicle where the action of pushing it into the housing,and thereafter removing the key, locks it in a safe position and at the same time actuates a microswitch which has been wired into the car's ignition system so that when in use with an empty stow-away bracket the ignition system is in open circuit as well as the exhaust being chocked.

3.A vehicle immobilisation device according to Claim 1 wherein the front of the device is shaped and pressed into channels which guide the internal mechanim to the exhaust pin and also cover the ends of the exhaust pin thus preventing a thief from punching it through and out.

4,A vehicle immobilisation device according to Claim 1 where the internal spring locking mechanism can either be fixed within the middle part of the cylinderical body of the device by means of screws or rivets or alternatively housed at the keyend of the body in a shaped or moulded block of material which is retained in the body by means of pressed indentations.

5.A vehicle immobilisation device substantially as described herein with reference to Figures 1 to 5 of the accompanying drawings.