GB2444727A

GB2444727A - Vehicle tyre deflating device

Info

Publication number: GB2444727A
Application number: GB0624948A
Authority: GB
Inventors: Kevin Mcclean
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-12-14
Filing date: 2006-12-14
Publication date: 2008-06-18
Anticipated expiration: 2026-12-14
Also published as: GB2444727B; GB0624948D0; WO2008071954A1

Abstract

A vehicle tyre deflating device 1 comprising extendable support means 2 and one or more arms 3, 4 mounted thereon, in which a first end of the support means 2 is mounted to a carrier vehicle in use, in which the one or more arms 3, 4 are mounted to a second end of the support means 2, in which the one or more arms 3, 4 have a first position in which they are disposed in front of the support means 2 in the direction of extension, and a second position in which they are disposed substantially laterally to the second end of the support means 2, in which the one or more arms 3, 4 move from the first position to the second position at a predetermined point of extension of the support means 2, and in which the one or more arms carry tyre deflation means 7.

Description

VEHICLE lYRE DEFLATING DEVICE This invention relates to a vehicle tyre

deflating device for use particularly, but not exclusively, to prevent vehicles escaping from law enforcement officers.

The puncturing of a vehicle's tyres is an effective way to disable it. A vehicle with deflated tyres can only travel at slow speed, and is difficult to control. Therefore, some law enforcement agencies now use a manually operated device for puncturing a passing vehicle's tyres. These devices comprise an extendable base which carries a plurality of spikes. The user travels to a point ahead of a pursued vehicle's position, and deploys the device in its path.

These devices are veiy effective in bringing vehicles to a stop, but unfortunately they can be very dangerous to use. Criminals are now aware of these devices, and often attempt to swerve around them if they are used, which puts the officer who deployed it at very high risk. This practice has resulted in the death of at least one police officer in the UK.

An alternative approach is to mount a tyre puncturing device to a chasing vehicle, and to deploy it into the path of a pursued vehicle whilst on the move. For example, US 6527475 discloses a tyre deflator as described above, mounted to the side of a vehicle. It extends laterally from the rear quarter flank of the law enforcement vehicle, into the path of an overtaking vehicle.

A more dynamic approach is suggested in US 6623205 and US 5611408, which both disclose a device for puncturing the rear wheels of a pursued vehicle from behind. An extendable support extends from the front of a chasing vehicle, and has two spike carrying arms at its outer end. The arms are folded alongside the support as they pass between the rear wheels of the pursued vehicle, then whilst underneath the pursued vehicle they unfurl to be perpendicular to the support. The chasing -2..

vehicle then slows down, with the result that the pursued vehicle runs over the spikes.

However, the known versions of this arrangement suffer from a number of drawbacks. The principal problem is that in order to allow enough space for the arms to unfurl into the path of the rear wheels of the pursued vehicle, the outer end of the support has to be situated some distance in front of those rear wheels. If this is not achieved the arms strike the side or rear part of the rear wheels, which may not result in a puncture.

Another problem with the prior art is ensuring that the chasing vehicle does not suffer a puncture. In US 5611408 for example the puncturing structure is only connected to the chasing vehicle with a wire or the like, so once it is deployed the chasing vehicle must swerve out of the way to avoid running over it.

In addition, the mechanisms by which the arms are unfurled in prior art arrangements is quite complex, in US 6623205 in particular. This means the devices are more expensive to manufacture and to purchase, and there is a greater likelihood of failure.

The present invention is intended to overcome some of the above problems.

Therefore, according to the present invention a vehicle tyre deflating device comprises extendable support means and one or more arms mounted thereon, in which a first end of the support means is mounted to a carrier vehicle in use, in which the one or more arms are mounted to a second end of the support means, in which the one or more arms have a first position in which they are disposed in front of the support means in the direction of extension, and a second position in which they are disposed substantially laterally to the second end of the support means, in which the one or more arms move from the first position to the second position at a predetermined point of extension of the support means, and in which the one or more arms carry tyre deflation means.

Thus, with the arrangement of the present invention, the arms pivot at their trailing end, not their leading end. This prevents the problem of the arms deploying into the sides or rear parts of the tyres, and means that they are more likely to strike the front part of the rear wheels of the pursued vehicle first. It also means that the chasing vehicle does not need to be so close to the pursued vehicle for the device to be used.

In a preferred embodiment two arms can be provided. In the first position the two arms can be arranged substantially parallel to one another, and substantially parallel to an axis of extension of the support means. In the second position a first of the two arms can be arranged substantially perpendicular to the second end of the support means, and a second of the two arms can also be arranged substantially perpendicular to the second end of the support means, but in the opposite direction.

Thus, the device forms a "r shape when the arms are in the second position.

Preferably the means by which the arms unfold can be automatic. The arms can be spring loaded, and be biased into the second position, and a locking means can holds the two arms In the first position until said pre-determined point of extension of the support means.

It will be appreciated that the support means can comprise any device which can extend, however, in a preferred embodiment the support means can comprise a pair of overlying multi-pivoted bars, joined together at a number of hinge points alternately spaced between pivot points. Such an arrangement is generally referred to a "lazy tongs". The arms can be hinged to the support means at a leading hinge point.

The use of lazy tongs" allows a very simple and expedient automatic arrangement for deploying the arms into the second position. This is because parts of the support means move relative to each another when it is extended, and these relative movements can be employed to facilitate the deployment of the arms.

In particular the two pivoted sections of each of the overlying bars nearest to the arms are arranged almost perpendicular to the leading hinge point when the device is folded up, but rotate away from the leading hinge point when the support extends. In addition the leading hinge point and hinge points behind it move apart when the device is extended. These relative movements are used to deploy the arms in a powerful and precise manner.

In particular, each arm can be spring loaded by means of a coil spring mounted in extension between the arm and a point on one of said bars set back from said leading hinge point. Thus, when the device is folded up, the amount of extension on the spring can be low, because said point wIll be near the arms, but when the support is extended, and said point rotates away from the arms, the springs are subjected to a far greater extension loading. This is used to power the movement of the arms from the first position to the second.

The locking means can comprise a rod, a first end of which is mounted to one of the hinge points of the support means other than the leading hinge point, and connector means mounted on each of said arms. The connector means can be mounted on said rod when the arms are in the first position, and the rod can release the connector means at said pre-determined point of extension. This is achieved because the hinge point at which the first end of the rod is mounted moves away from the arms when the support means is extended, and therefore the rod will slide out from the connector means at a particular point, thereby releasing the arms. It will be appreciated that the exact point when the arms are deployed can be controlled by changing the length of the rod. The shorter it is the sooner the arms will deploy.

The connector means can comprise substantially C-shaped clips provided with openable closure means. This arrangement allows the device to be more readily folded up because the arms can be returned to the first position regardless of the extent of extension of the support means, and therefore the position of the rod.

In a preferred embodiment of the invention the arms can each be provided with a telescoping section, which can be housed within the arms in the first position, and can be fully extended from the arms in the second position.

Again, a simple arrangement can be employed to operate the telescoping sections in an expedient manner. They can be spring loaded, and be biased towards the arms, but their inner ends can be connected by a wire which is threaded around pulley wheels mounted at outer ends of the arms. With this arrangement, the inner ends of the telescoping sections are pulled towards said pulley wheels -which forces the telescoping sections out -when the arms are in the second position.

The Lyre deflation means can comprise a plurality of spikes. The spikes can be of the known hollow construction which pierce a Lyre, and rapidly deflate it.

In one version of the invention the spikes can be mounted on a body with a substantially right-angle triangle shaped cross-section, and the spike can extend from the hypotenuse side of the cross-section and be substantially perpendicular thereto.

The bodies can be mounted on the arms with said hypotenuse sides facing opposite to the direction of travel of the carrier vehicle -in other words with the spikes facing the rear wheels of the pursued vehicle.

The arms can be provided with mounting rods, and said bodies can be mounted thereon with resilient C-clips extending from their upright sides. Such an arrangement allows for the bodies to be securely fixed to the arms during deployment of the device, but readily removed if a Lyre runs over them.

The support means described above can be moved from a folded position to an extended position by moving the pivot points of each bar closer together. This is most readily done by moving together the inner ends of the bars, which are not joined at a hinge point.

In a preferred construction the inner ends of the bars of the support means can be mounted on a screw, such that rotation of the screw in a first direction forces the inner ends together, thereby to extend the support means, and rotation of the screw in the opposite direction forces the inner ends apart, thereby to fold the support means up.

In order to deploy the support means quickly and effectively, the screw can be powered. In one embodiment the screw can be rotated by an electric motor.

In a preferred arrangement each end of the screw can be supported by the sides of a tray, which can be mounted to the underside of the carrier vehicle. The tray can be dimensioned to support the support means when it is folded up.

In one version of the invention the first end of the support means can be mounted to the carrier vehicle in a sliding relationship. To facilitate this, the first end of the support means can be provided with a slide means adapted to allow it to move backwards and forwards in relation to the carrier vehicle. Biasing means can be provided to bias the first end of the support means towards the front the carrier vehicle. The feature is intended to prevent the device from being damaged in use, and is explained in greater detail below.

As referred to above, the main purpose of this device is to puncture the tyres of vehicles which are being pursued. Therefore, in a preferred embodiment the device can be adapted to be mounted to the front of the carrier vehicle SUCh that the device is employed in such a way.

However, it is also possible to use the device of the invention to puncture the tyres of a following vehicle. Therefore, in an alternative arrangement the device can be adapted to be mounted to the rear of the carrier vehicle such that the device is employed in use to stop pursuing vehicles.

Whether the device is forward or rearward facing, it can also be used when the carrier vehicle is stationary. In other words, the carrier vehicle can park behind a suspect vehicle and deploy the device. If the suspect vehicle attempts to flee it will run over the spikes. The use of the "lazy tongs" arrangement makes it a simple matter to deploy the device very quickly when on the move, or more SI owly and discretely when stationary. The electric motor referred to above can be adapted to rotate the screw as fast as possible and slower in order to facilitate this use.

The invention also includes a vehicle fitted with the above described device.

Therefore, according to a second aspect of the present invention a vehicle is provided with a vehicle tyre deflating device comprising extendable support means and one or more arms mounted thereon, in which a first end of the support means is mounted to the vehicle, in which the one or more arms are mounted to a second end of the support means, in which me one or more arms have a first position in which they are disposed in front of the support means in the direction of extension, and a second position in which they are disposed substantially laterally to the second end of the support means, in which the one or more arms move from the first position to the second position at a predetermined point of extension of the support means, and in which the one or more arms carry tyre deflation means.

The invention can be performed in various ways, but one embodiments will now be described by way of example and with reference to the accompanying drawings in which: Figure 1 is a top view of a vehicle tyre deflating device according to the present invention in an extended arrangement; Figure 2 is a top view of the vehicle tyre deflating device as shown in Figure 1 in a folded up position; Figure 3 is a partial top view of the vehicle tyre deflating device as shown in Figure 1; and Figure 4 is a cross-sectional side view of components of the vehicle tyre deflating device as shown in Figure 1.

As shown in Figure 1, a vehicle lyre deflating device 1 comprises extendable support means 2 and one or more arms mounted thereon, in the form of arms 3 and 4. A first end 5 of the support means 2 Is mounted to a camer vehicle (not Shown) in use as described below, and the one or more arms (3,4) are mounted to a second end 6 of the support means 2.

As is clear from Figures 1 and 2, the one or more arms (3,4) have a first position, as shown in Figure 2, in which they are disposed in front of the support means 2 in the direction of extension, as indicated by arrow A, and a second position, as shown in Figure 1, in which they are disposed substantially laterally to the second end 6 of the support means 2. As is further described below, the one or more arms (3, 4) move from the first position to the second position at a predetermined point of extension of the support means 2. The one or more arms (3, 4) carry tyre deflation means, in the form of spikes 7.

(The following description refers to Figures 1 and 2, however for ease of understanding Figure 3 shows arm 3 In greater detail.) The support means 2 comprises a "lazy tongs" extender made up of a pair of overlying multi-pivoted bars 8 and 9, which are joined together at a number of hinge points 10 alternately spaced between pivot points 11.

The arms 3 and 4 are hinged to the second end 6 of the support means 2 at a leading hinge point 12. Coil springs 13 and 14 are mounted in extension between the arms 3 and 4 and the support means 2, such that the arms 3 and 4 are forced to rotate about the hinge point 12 and assume the second position.

The arms 3 and 4 are rigid bodies with a leading edge 15 and a trailing edge 16. These edges are "leading" and "trailing" when the arms 3 and 4 are in their second position as shown in Figure 1. The arms 3 and 4 are hinged to the leading hinge point 12 at their Inner leading corner 17. An inner edge 18 contacts the leading section 19 of the bars 8,9 when the arms 3 and 4 are in the second position shown in Figure 1, and the inner edge 18 is angled such that when this occurs, the arms are perpendicular to the support means 2, as shown in Figure 1.

The device 1 is provided with a locking means adapted to lock the arms 3 and 4 in the position shown in Figure 2. The arms 3 and 4 are provided with connector clips 20 and 21, and a rod 22 is mounted on the support means 2, at a second hinge point 23. An eyelet 22a (indicated in Figure 3) is provided on the leading hinge point 12, through which the rod 22 passes, Such that it always extends in the direction of extension of the support means 2, as indicated by arrow A. As shown in Figure 2, the connector clips 20 and 21 can be connected to the rod 22, thereby locking the arms 3 and 4 in the first position. The connector clips 20 and 21 comprise C-shaped slips with openable closure means, in the form of spring loaded catches (not visible). The catches are arranged to allow access into the clip, but not exit. Thus, the arms 3 and 4 can be manually forced into the first position, and the clips 20 and 21 can be applied to the rod 22, such that the rod 22 is captured therein.

It will be appreciated that the leading hinge point 12 and the second hinge point 23 move apart when the support means 2 is extended, and it is this movement which is used to release the arms 3 and 4 and allow them to move from the first position to the second position.

When the support means 2 extends in use, the rod 22 moves back from the clips 20 and 21 because the hinge points 12 and 23 move apart. At a point of extension just prior to that shown in Figure 1, the rod 22 slides out from clip 21 releasing arm 4, which is rotated into the second position by spring 14. Just after that the rod 22 slides out from clip 20, releasing arm 3, which is rotated into the second position by spring 13.

It will also be appreciated that the coil springs 13 and 14 are forced into greater extension as the support means 2 extends, because the leading sections 19 of the bars 8 and 9 rotate away from the arms 3 and 4. Thus, at the point of release described above, the springs 13 and 14 are subjected to a high degree of extension, and thus a high force is employed to move the arms 3 and 4 from the first position to the second.

The arms 3 and 4 are provided with telescoping sections 24 and 25 respectively. The arms 3 and 4 are provided with channels 26 in their bodies, in which the telescoping sections 24 and 25 can slide in and out. As is clear from Figures 1 and 2, in the first position the telescoping sections 24 and 25 are housed completely within the arms 3 and 4, and in the second position they are extended to their greatest extent.

Coil springs 27 (visible only in Figure 3) are mounted between the telescoping sections 24 and 25 and the arms 3 and 4, and bias the sections 24 and 25 into the arms 3 and 4. However, the inner ends of each section 24 and 25 are connected by a wire 28 which is threaded around pulley wheels (not visible) mounted at outer ends of the channels 26.

Thus, when the arms 3 and 4 are in the first position shown in Figure 2, the wire (not visible in Figure 2) extends from the Inner ends of the sections 24 and 25, through the channels 26, and around the pulley wheels (not visible).

However, when the arms 3 and 4 are released into the second position, as described above, the pulley wheels (not visible) are forced apart, forcing the wire 28 to pull the telescoping sections 24 and 25 out of their channels 26.

When the arms 3 and 4 are forced back into the first position the springs 27 force the telescoping sections 24 and 25 back into the arms 3 and 4.

Both the arms 3 and 4, and the telescoping sections 24 and 25, carry spikes 7. Each spike 7 is removably mounted in position, such that if it punctures a tyre in use, it is pulled free from the device 1. In order to facilitate this, the spikes 7 are mounted on bodies 29, as shown in Figure 4, which are themselves mounted to the arms 3 and 4. Referring to Figure 4, the bodies 29 comprise right-angle triangle shaped members, which carry the spikes 7 extending from the hypotenuse side 30.

The spikes 7 are hollow, and extend through the bodies 29, such that if they puncture a tyre an open path is created for the air in the lyre to escape.

The bodies are provided with C-clips 31 on a rear side 32, which resiliently mount to rods 33. whIch are provided on the arms 3 and 4 and the telescoping sections 24 and 25. The rods 33 extend along the length of the arms 3 and 4 and the sections 24 and 25, such that a large number of spikes 7 are provided, as is clear from Figure 3.

The resilient clips 31 are adapted to safely secure the bodies 29 to the rods 33 during extension of the device 2, but are adapted to allow the bodies 29 to be pulled from the rods 33 if they puncture a lyre.

It wifl be appreciated that the hypotenuse side 30 of the bodies 29 face opposite to the direction of travel of the carrier vehicle (not shown). Thus, the hypotenuse sides 30 are presented to the rear wheels of the pursued vehicle, and that vehicle rides over the hypotenuse sides in use. With this arrangement the full weight of the pursued vehicle is forced down onto the spikes 7, ensuring a puncture.

Referring back to Figure 1, the inner end 5 of the support means 2 ends at two free "pivot points" 34. The movement of these points 34 towards and away from each other extends and retracts the support means 2. In order to facilitate this, the points 34 are mounted on screw bodies (not visible), which are themselves mounted on screw 35. The screw 35 has two threaded sections, which are threaded in opposite directions, such that rotation of the screw 35 in one direction brings the screw bodies together, and in the other direction moves them apart. The screw 35 is rotated by an electric motor (not shown).

The ends of the screw 35 are supported by the side walls (not visible) of tray 36. The tray 36 comprises a base 37, said side walls, and flanges 38 which extend laterally from the top of said side walls. The flanges 38 can be attached to the underside of a carrier vehicle (not shown) in any suitable manner, for example with screws. As is clear from Figure 2. the tray 36 is dimensioned to support the support means 2 when it is folded up.

In use, the device 1 functions as follows. The tray 36 is secured to the underside of a carrier vehicle (not shown), so the device can travel between the front wheels when it deploys. Preferably it is positioned so the ends of the arms 3 and 4 do not protrude further than the front bumper.

Prior to deployment the bodies 29 are mounted on the rods 33. The device is flexible, in that it can carry a maximum quantity of bodies 29, as shown in the Figures, or a smaller number if desired. Clearly, the more bodies 29, the greater the chance of puncturing a pursued vehicle's tyres. The device I is then folded up into the first position as shown in Figure 2. The support means 2 is pushed back towards the tray 36. and the points 34 are forced apart on the screw 35. At the same time the arms 3 and 4 are rotated towards each other until they are parallel. As this is done the pulley wheels (not visible) come together, and the wire 28 allows the telescoping sections 24 and 25 to be pulled back into the arms 3 and 4 by the springs 27.

As the arms 3 and 4 are brought together, the connector clips 20 and 21 are brought into contact with the rod 22, and secure themselves to it, thereby locking the arms 3 and 4 in the fist position.

It will be appreciated that it will be easier to rotate the arms 3 and 4 together the lesser the support means 2 is extended, because the springs 13 and 14 wilt need to be placed under less extension force.

The device 1 is now ready for deployment. The device 1 can be used in a number of ways, and in a number of circumstances. However, the prime aim of the device 1 is to bring fleeing vehicles to a stop. To do this most effectively, the carrier vehicle (not shown) positions itself directly behind the pursued vehicle, and close enough such that the distance between the screw 35 and the front side of the rear tyres of the pursued vehicle is the same as or less than the length of the support means 2 when fully extended.

Once in position, the device 1 is deployed by operating a switch in the cabin of the carrier vehicle (not shown), which operates the electric motor (not shown). The electric motor rotates the screw 35 at a high velocity, such that the points 34 are brought together and the support means 2 is forced into extension at high speed.

It is important that the device extends down to the ground, and does not lift up in use. It will be appreciated that the lazy tongsR arrangement is prone to dipping along its length, and that is what occurs here due to the weight of the arms 3 and 4 at the outer end 6. As the support means 2 extends it dips down towards the ground.

The underside of the arms 3 and 4 and the leading hinge point 12 are provided with a hardened skid (not visible) adapted to slide along a road at high speed.

As the support means 2 extends, the leading hinge point 12 and the second hinge point 23 move apart, and the rod 22 moves back. Just prior to the point of full extension, the rod 22 slips free from the connector clips 20 and 21, releasing the arms 3 and 4. Once released from the first position, the arms 3 and 4 are pulled into the second position by the springs 13 and 14, and the telescoping sections 24 and are simultaneously pulled out by virtue of being connected together by the wire 28.

Once the arms 3 and 4 are in the second position, the chasing vehicle brakes, thereby putting the arms 3 and 4 in the path of the rear wheels of the pursued vehicle.

When the tyres of the rear wheels of the pursued vehicle run over the spikes 7, the bodies 29 are pulled free from the rods 33 and the tyres are impaled on the spikes 7 and deflated.

(It will be appreciated that the shorter the support means 2 when fully extended, the closer the chasing vehicle will have to be. Clearly, the closer it has to be the higher the risk of collision. The device 1 shown In the Figures is relatively short in length, but it will be appreciated that it can readily be lengthened by adding more sections to the bars 8 and 9, or by making the sections longer.) The device 1 has a number of advantages over prior art arrangements. The first is that the arms are carried in front of the support means 2, and unfold back towards it. This means that the leading hinge point 12 need only draw level with the rear wheels of the pursued vehicle. This is advantageous over prior art devices in which the arms unfold from the sides of the support means in the opposite direction to in the present case, because with such systems the leading point of the support means must be some distance further ahead than the rear wheels of the pursued vehicle to allow the arms space to unfold in front of them.

In addition, the present device 1 can also be effective if the leading hinge point 12 has not drawn level with the rear wheels of the pursued vehicle, although it works best in such circumstances. Provided the arms 3 and 4 have drawn level with the rear tyres of the pursued vehicle when they are released, they may come into contact with the tyres at some point between the first and the second position because they fold back towards the tyres. In such circumstances the arms 3 and 4 contact with the rear tyres of the pursued vehicle at some angle between 0 and 90 degrees, but if so the spikes 7 may still puncture the tyre and be effective.

This advantageous feature is enhanced by the use of the telescoping sections 24 and 25, which unfurl out towards the rear tyres of the pursued vehicle when the arms 3 and 4 are released, thereby providing a greater chance of some contact being made between the device 1 and the tyres.

It will be appreciated that when a moving tyre runs over a moving object, that object is momentarily stopped because it becomes trapped between the tyre and the road. If the arms 3 and 4 are travelling forwards in use, and were then momentarily stopped dead, then there would be a risk of breakage as the chasing vehicle continued to move forwards. This does not occur because the bodies 29 are removable from the rods 33. When the device I is deployed at speed and a tyre runs onto the bodies 29, the bodies 29 momentarily stop dead. At this point the C-clips 31 separatefrom the rods 33, which continue to move forwards with the rest of the device 1. The shape of the bodies 29 acts like a mini ramp lifting the tyres over the rods 33 so that they can continue traveling forwards underneath the tyres running over them, without being damaged.

Another advantage of the device 1 is that it is a simple mechanism with few moving parts, in particular the locking and releasing mechanism of the rod 22. which utilises the physical characteristics of the "lazy tongs" arrangement to operate. In addition the whole "lazy tongs" arrangement is also very simple and easy to deploy, as it only requires that the two free ends 34 are brought together.

Once the device has been used as described above, it can be folded back up into the first position as described above. If spikes 7 have been released from the device 1, further bodies 29 can be added to the rods 33 to replenish the supply. If none are available, and the device 1 is to be used again, the user can position the remaining spikes 7 in the most likely part of the arms 3 and 4 to run under a pursued vehicle's rear tyres, which are on the telescoping sections 24 and 25.

In addition to the manner of use described above, the device 1 can also be used in other ways. The device 1 may still be effective if the chasing vehicle is not directly behind the pursued vehicle. All that is necessary is to be in a position such that one of the arms 3 or 4 will be disposed in front of one of the tyres of the pursued vehicle when the device 1 is unfolded. This can be achieved if the chasing vehicle is behind the pursued vehicle, but to one side. The device I can be deployed outside the nearest rear wheel of the pursued vehicle, and one arm can be presented to that rear wheel.

Further, the device I shown in the Figures is dimensioned such that when the arms 3 and 4 are in the second position shown in Figure 1, the span of the arms 3 and 4 is generally slightly more than the width of the largest cars the device may be used on. As a result, the outer part of the telescoping sections 24 and 25 may extend laterally further than the side of the carrier vehicle. Thus, the device 1 may be effective If the chasing vehicle is right along side the pursued vehicle. The device 1 can be deployed, and the chasing vehicle can break, such that the front and/or the rear wheels on one side of the pursued vehicle run over the outer edge of one of the telescoping sections 24, 25.

It will be appreciated that the arms 3 and 4 could be dimensioned such that their span is significantly greater than the width of the carrier vehicle, so the above manner of use is more possible.

In addition to using the device I to stop a pursued vehicle, it can also be used to prevent a parked vehicle from escaping. The carrier vehicle parks directly behind the subject vehicle and the device is deployed, such that the arms are disposed underneath it. If any attempt is made to escape, the fleeing vehicle will run over the arms 3 and 4 and its tyres wilt be punctured. This manner of use could be very useful to law enforcement agents who pull over a suspicious or law breaking vehicle, and are worried that it may try to escape once they exit their vehicle.

Further, it is also possible to fit the device 1 to parts of the carrier vehicle other than the front. In particular, it could be rear mounted. In such circumstances the advantages of having the arms 3 and 4 fold back towards the support means 2 rather than away from it are lost The invention also includes a vehicle provided with a vehicle tyre deflating device as described above. Such a vehicle is not shown in the Figures, but it will be appreciated how such a vehicle can be constructed by fitting the device as described above to an existing vehicle.

The above described embodiment can be altered without departing from the scope of Claim 1. In particular, in an alternative embodiment (not shown) a device like device 1 is provided with a further feature adapted to prevent potential damage in use. The tray component is mountable to the underside of the vehicle in a sliding arrangement, such that if the arms of the device are momentarily stopped dead in use, as referred to above. the tray slides back as the chasing vehicle continues to move forwards. This prevents the arms from breaking off the support means if they stop dead and the support means carries on. In such an arrangement the flanges of the tray component can be attached to a runner" or slide" arrangement of any known type. Return springs can be used to bias the tray into its forward position.

This arrangement allows the alternative embodiment to be used with spikes which are fixed to the arms, as there may be no need to provide the releasable spikes feature to prevent damage, although both of these features can be incorporated if desired.

In another alternative embodiment (not shown) a device is like device 1, except that its arms are not provided with telescoping sections.

Therefore, a vehicle tyre deflating device is provided with arms which fold back towards the tyres of a pursued vehicle, which significantly increases its effectiveness. In addition, an arrangement is provided with is simple and inexpensive to construct, and therefore to purchase and use. Further, a vehicle tyre deflating device is provided which ensures that the carrier vehicle is never attached to the subject vehicle.

Claims

Claims 1. A vehicle tyre deflating device comprising extendable support

means and one or more arms mounted thereon, in which a first end of the support means is mounted to a carrier vehicle in use, in which the one or more arms are mounted to a second end of the support means, in which the one or more arms have a first position In which they are disposed in front of the support means in the direction of extension, and a second position in which they are disposed substantially laterally to the second end of the support means, in which the one or more arms move from the first position to the second position at a predetermined point of extension of the support means, and in which the one or more arms carry tyre deflation means.
2. A vehicle tyre deflating device as claimed in Claim 1 in which two arms are provided, and in which in the first position the two arms are arranged substantially parallel to one another, and substantially parallel to an axis of extension of the support means, and in which in the second position a first of the two arms is arranged substantially perpendicular to the second end of the support means, and a second of the two arms is arranged substantially perpendicular to the second end of the support means in the opposite direction.
3. A vehicle tyre deflating device as claimed in Claim 2 in which the arms are spring loaded, and are biased into the second position, and in which a locking means holds the arms in the first position until said pre-determined point of extension of the support means.
4. A vehicle tyre deflating device as claimed in Claim 3 in which the support means comprises a pair of overlying multi-pivoted bars, joined together at a number of hinge points alternately spaced between pivot points, and in which the arms are hinged to the support means at a leading hinge point.
5. A vehicle tyre deflating device as claimed in Claim 4 in which each arm is spring loaded by means of a coil spring mounted in extension between the arm and a point on one of said bars set back from said leading hinge point.
6. A vehicle tyre deflating device as claimed in Claim 5 in which the locking means comprises a rod, a first end of which is mounted at a hinge point of the support means, and connector means mounted on each of said arms, in which the connector means are mounted on said rod when the arms are in the first position, and in which the rod releases the connector means at said pre-determined point of extension.
7. A vehicle tyre deflating device as claimed in Claim 6 in which the connector means comprise substantially C-shaped clips provided with openable closure means.
8. A vehicle tyre deflating device as claimed in Claim 7 in which the arms are each provided with a telescoping section, in which the telescoping section is housed within the arms in the first position, and in which the telescoping section is fully extended from the arms in the second position.
9. A vehicle tyre deflating device as claimed in Claim 8 in which the telescoping sections are spring loaded, and are biased towards the arms, in which inner ends of the two telescoping sections are connected by a wire which is threaded around pulley wheels mounted at outer ends of the arms, such that when the arms are in the second position, the inner ends of the telescoping sections are pulled towards said pulley wheels.
10. A vehicle tyre deflating device as claimed in any of the preceding Claims in which the tyre deflation means comprise a plurality of spikes.
11. A vehicle tyre deflating device as claimed in Claim 10 in which the plurality of spikes are removably mounted to the arms.
12. A vehicle tyre deflating device as claimed in Claim 11 in which each spike Is mounted on a body with a substantially right-angle triangle shaped cross-section, in which the spike extends from the hypotenuse side and is perpendicular thereto, and in which said bodies are mounted on said arms with said hypotenuse sides facing opposite to the direction of travel of the carrier vehicle.
13. A vehicle tyre deflating device as claimed in Claim 12 in which the arms are provided with spike body mounting rods, and in which the spike bodies are mounted thereon with resilient C-clips extending from their upright sides.
14. A vehicle tyre deflating device as claimed in any of Claims 4 to 13 in which inner ends of the bars of the support means are mounted on a screw, such that rotation of the screw in a first direction forces the inner ends together, thereby to extend the support means, and rotation of the screw in the opposite direction forces the inner ends apart, thereby to fold the support means up.
15. A vehicle tyre deflating device as claimed in Claim 14 in which the screw is rotated by an electric motor.
16. A vehicle tyre deflating device as claimed In Claim 15 in which the screw is supported by the sides of a tray, which tray is mounted to the underside of the carrier vehicle, and in which the tray is dimensioned to support the support means when it IS folded up.
17. A vehicle tyre deflating device as claimed in any of the preceding Claims in which the first end of the support means is mounted to the carrier vehicle in a sliding relationship.
18. A vehicle lyre deflating device as claimed in Claim 17 in which the first end of the support means is provided with a slide means adapted to allow the first end of the support means to move in relation to the carrier vehicle in a rearward direction of the carrier vehicle and in a forward direction of the carrier vehicle, and in which biasing means are provided which are adapted to bias the first end of the support means towards a front end of the carrier vehicle.
19. A vehicle tyre deflating device as claimed in any of the preceding Claims in which the device is adapted to be mounted to the front of the carrier vehicle such that the device is employed in use to stop vehicles being pursued.
20. A vehicle tyre deflating device as claimed in any of Claims 1 to 17 in which the device is adapted to be mounted to the rear of the carrier vehicle such that the device is employed in use to stop pursuing vehicles.
21. A vehicle lyre deflating device substantially as described herein and as shown in the accompanying Figures.
22. A vehicle provided with a vehicle tyre deflating device comprising extendable support means and one or more arms mounted thereon, In which a first end of the support means is mounted to the vehicle, in which the one or more arms are mounted to a second end of the support means, in which the one or more arms have a first position in which they are disposed in front of the support means in the direction of extension, and a second position in which they are disposed substantially laterally to the second end of the support means, in which the one or more arms move from the first position to the second position at a predetermined point of extension of the support means, and in which the one or more arms carry tyre deflation means.
23. A vehicle substantially as described herein.

23. A vehicle substantially as described herein.

Amendments to the claims have been filed as follows 1. A vehicle tyre deflating device comprising extendable support means and one or more arms mounted thereon, in which a first end of the support means is mounted to a carrier vehicle in use, in which the one or more arms are mounted to a second end of the support means, in which the one or more arms have a first position In which they are disposed in front of the support means in the direction of extension, and a second position in which they are disposed substantially laterally to the second end of the support means, in which the one or more arms move from the first position to the second position at a predetermined point of extension of the support means, and in which the one or more arms carry tyre deflation means.

2. A vehicle tyre deflating device as claimed in Claim I in which two arms are provided, and in which in the first position the two arms are arranged substantially parallel to one another, and substantially parallel to an axis of extension of the support means, and in which in the second position a first of the two arms is arranged substantially perpendicular to the second end of the support means, and a second of the two arms is arranged substantially perpendicular to the second end of the support means in the opposite direction.

3. A vehicle tyre deflating device as claimed in Claim 2 in which the arms are spring loaded, and are biased into the second position, and in which a locking means holds the arms in the first position until said pre-determined point of extension of the support means.

4. A vehicle tyre deflating device as claimed in Claim 3 in which the support means comprises a pair of overlying multi-pivoted bars, joined together at a number of hinge points alternately spaced between pivot points, and in which the arms are hinged to the support means at a leading hinge point. 2.M-

5. A vehicle tyre deflating device as claimed in Claim 4 in which each arm s spring loaded by means of a coil spring mounted in extension between the arm and a point on one of said bars set back from said leading hinge point.

6. A vehicle tyre deflating device as claimed in Claim 5 in which the locking means comprises a rod, a first end of which is mounted at a hinge point of the support means other than the leading hinge point, and connector means mounted on each of said arms, in which the connector means are mounted on said rod when the arms are in the first position, and in which the rod releases the connector means at said predetermined point of extension.

7. A vehicle tyre deflating device as claimed in Claim 6 in which the connector means comprise substantially C-shaped clips provided with openable closure means. * *

8. A vehicle tyre deflating device as claimed in Claim 7 in which the arms are * *** each provided with a telescoping section, in which the telescoping section is housed within the arms in the first position, and in which the telescoping section is fully *. extended from the arms in the second position. S...

: 9. A vehicle tyre deflating device as claimed in Claim 8 in which the telescoping * * sections are spring loaded, and are biased towards the arms, in which inner ends of the two telescoping sections are connected by a wire which is threaded around pulley wheels mounted at outer ends of the arms, such that when the arms are in the second position, the inner ends of the telescoping sections are pulled towards said pulley wheels.

10. A vehicle tyre deflating device as claimed in any of the preceding Claims in which the tyre deflation means comprise a plurality of spikes.

11. A vehicle tyre deflating device as claimed in Claim 10 in which the plurality of spikes are removably mounted to the arms.

I z5

12. A vehicle tyre deflating device as claimed in Claim 11 in which each spike is mounted on a body with a substantially right-angle triangle shaped cross-section, in which the spike extends from the hypotenuse side and is perpendicular thereto, and in which said bodies are mounted on said arms with said hypotenuse sides facing opposite to the direction of travel of the carrier vehicle.

13. A vehicle tyre deflating device as claimed in Claim 12 in which the arms are provided with spike body mounting rods, and in which the spike bodies are mounted thereon with resilient C-clips extending from their upright sides.

14. A vehicle tyre deflating device as claimed in any of Claims 4 to 9 or 10 to 13 when dependent on Claim 4, in which inner ends of the bars of the support means are mounted on a screw, such that rotation of the screw in a first direction forces the inner ends together, thereby to extend the support means, and rotation of the screw :. in the opposite direction forces the inner ends apart, thereby to fold the support * **.

means up. * S *55*

:. 15. A vehicle tyre deflating device as claImed in Claim 14 in which the screw is

J

* rotated by an electric motor. ***

16. A vehicle tyre deflating device as claimed in Claim 15 in which the screw is *. : supported by the sides of a tray, which tray is mounted to the underside of the carrier * S. vehicle, and in which the tray is dimensioned to support the support means when it is folded up.

17. A vehicle tyre deflating device as claimed in any of the preceding Claims in which the first end of the support means is mounted to the carrier vehicle in a sliding relationship.

18. A vehicle tyre deflating device as claimed in Claim 17 in which the first end of the support means is provided with a slide means adapted to allow the first end of the support means to move in relation to the carrier vehicle in a rearward direction of ZL' the carrier vehicle and in a forward direction of the carrier vehicle, and in which biasing means are provided which are adapted to bias the first end of the support means towards a front end of the carrier vehicle.

19. A vehicle lyre deflating device as claimed in any of the preceding Claims in which the device is adapted to be mounted to the front of the carrier vehicle such that the device is employed in use to stop vehicles being pursued.

20. A vehicle lyre deflating device as claimed in any of Claims 1 to 17 in which the device Is adapted to be mounted to the rear of the carrier vehicle such that the device is employed in use to stop pursuing vehicles.

21. A vehicle lyre deflating device substantially as described herein and as shown in the accompanying Figures.

22. A vehicle provided with a vehicle lyre deflating device comprising extendable support means and one or more arms mounted thereon, in which a first end of the support means is mounted to the vehicle, in which the one or more arms are mounted to a second end of the support means, in which the one or more arms have a first position in which they are disposed in front of the support means in the direction of extension, and a second position in which they are disposed substantially laterally to the second end of the support means, in which the one or more arms move from the first position to the second position at a predetermined point of extension of the support means, and in which the one or more arms carry lyre deflation means.