GB2256176A

GB2256176A - A rotatable mechanism for preventing semi trailer theft

Info

Publication number: GB2256176A
Application number: GB9111543A
Authority: GB
Inventors: Michael Peter Johnson; Malcolm Lowe
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-05-29
Filing date: 1991-05-29
Publication date: 1992-12-02
Anticipated expiration: 2011-05-29
Also published as: GB2256176B; GB9111543D0

Abstract

The mechanism comprises a support 3 which can be fitted to the underside of a vehicle trailer in line with a projection 12, by which the trailer is connected to a tractor unit, on the fore-aft axis of the trailer. A part spherical member 1 may be pivoted between a first position in which the plain face of the member is substantially flush with the undersize of the trailer and a second position in which the member 1 obstructs access to the projection 12. A lever 10 is provided for pivoting the member 1 and a lock 11 is provided for locking the lever in position. <IMAGE>

Description

AN ADJUSTABLE MECHANISM The present invention relates to an adjustable mechanism.

The mechanism is intended particularly, but not exclusively as a security device. It may be used for example as a security device to prevent unauthorised removal to lorry trailers. At the present time such trailers may be left, often loaded with valuable goods, at a particular location ready for subsequent removal.

The trailer incorporates a downwardly dependent projection which may be received by and locked into a corresponding complementary slot in a plate carried on a tractor unit. The trailer and tractor unit are locked together in this way allowing the tractor unit to pull the trailer. If access to this projection is not prevented an unauthorised tractor unit may lock onto the trailer and remove it to another location for unauthorised removal of the goods in the trailer.

According to the present invention, there is provided a mechanism comprising a support, a movable member mounted in the support for movement between a first inoperative position and a second operative position in which the member provides an bbstruction and means for preventing movement of the member from the second position.

In a preferred embodiment in which the mechanism is to be fixed to a trailer, the support comprises a circular plate to be fixed, for example by welding, to the undersurface of the trailer. This plate defines a circular aperture in which the member, which is part spherical in shape, is pivotally mounted. The pivotal mounting comprises two projections extending from the support into the trailer body on opposite sides respectively of the member. A pivot pin extends through the member and respective projections. The shape of the member is such that in the first inoperative position a plain face of the member lies flush with the undersurface of the trailer and the spherical surface of the member lies wholly within the trailer body. In the second operative position the spherical surface of the member depends below the trailer undersurface.The mechanism is fixed to the trailer in front of the projection onto which the tractor unit locks. In the second operative position, the member prevents access to the projection.

An attempt to displace the member is resisted by the spherical shape which deflects blows from any direction.

Similarly, the spherical shape presents no surface on which purchase may be gained in an attempt to use the member as a tow connection itself. A lever may be provided for pivoting the member and a locking member may be disposed on that lever locking the lever and therefore the member in a desired position. A stop may be provided on the member to facilitate pivoting of the member to the correct position relative to the support. The stop which abuts the support in the two positions may be adjustable.

The mechanism may be made from any suitable material such as metal or synthetic plastics material.

In order that the invention may be more clearly understood, one embodiment thereof will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevational view of a mechanism according to the invention, Figure 2 is a plan view of the mechanism of Figure 1 and Figure 3 is a partial view of the mechanism of Figures 1 and 2 shown in position in a trailer.

Referring to the drawings, the mechanism comprises a part spherical member 1. The member 1 is mounted for pivotal movement in the circular aperture 2 of a support 3. The member 1 is solid and made of metal and the support 3 is a metal plate which is formed with a shoulder 4 which fits into a complementary aperture 5 in the undersurface of the trailer body 6. To secure the plate 3 in position, it is welded to the trailer body 6 at 7. The pivotal mounting of the member 1 comprises two projections 8, which each define an aperture, and which extend into the trailer body on opposite sides of the member 1. A pivot pin 9 extends through the member 1 and the two projections 8 to provide the pivotal axis of the member. A lever 10 is connected to the pivot 9 to rotate the member 1 in the support 3.This lever is accessible from inside the trailer and is locked in position either by a lock 11 or by a padlock connecting the lever to a fixed.point on the trailer.

The mechanism is disposed forward of the downwardly dependant projection 12 which provides the fixing for locking a trailer to a tractor unit. The mechanism and projection are substantially in line on the forward-aft axis of the trailer. To prevent unauthorised access to the projection, the member 1 is pivotted from the position shown in Figure 1, in which the plain face 13 of the member 1 lies substantially flush with the undersurface of the trailer body 6, to a position in which the spherical envelop of the member 1 coincides with the dashed line 14. In this position, the member obstructs any attempt to lock onto the projection 12.

Furthermore its spherical surface deflects any attempt to displace it by force and also presents no surface which itself can be locked onto. Adjustable stops comprising two screwthreaded bolts 15 and 16 screwed into complementary nuts 17 and 18 fixed to bracket 19 fixed in turn to the spherical member are provided to facilitate positioning the member 3 in the correct position relative to support 1. In the operative position just described stop 15 would abut the support 3 on the other side of the member i to the side in which it is shown on Figure 1.

It will be appreciated that the above embodiment has been described by way of example only and that many variations are possible without departing from the scope of the invention. For example, although the mechanism has been described for use as a security device on a trailer it could also be used as a stop for a door for example. Also although the spherical shape of the member 1 is preferred other shapes could be employed. Further, the pivotal axis of the member 1 could be differently orientated.

Claims

1. A mechanism comprising a support, a movable member mounted in the support for movement between a first inoperative position and a second operative position in which the member provides an obstruction and means for preventing movement of the member rnrom the second position.

2. A mechanism as claimed in claim 1a in which the support comprises a circular plate to be Bed to the underside of a vehicle trailer.

3. A mechanism as claimed in claim 1 or 2, in which the support defines a circular aperture in wich Buzz the member is pivotally mounted.

4. A mechanism as claimed in claim 111 2 or 3, in which the member is part spherical.

5. A mechanism as claimed in claim 3, in which the pivotal mounting comprises two projections extending from the support on opposite sides respectively of the member.

6. A mechanism as claimed in any preceding claim in which a lever is provided for moving the member between the first and second positions.

7. A mechanism as claimed in any preceding claim, in which the means for preventing movement comprises a locking member.

8. A mechanism as claimed in any preceding claim, in which a stop is provided to facilitate moving of the member to the correct position relative to the support.

9. A mechanism as claimed in claim 8, in which the stop abuts the support in the first and second positions.

10. A mechanism as claimed in claim 9, in which the stop is adjustable.

11. A mechanism as claimed in any preceding claim made from metal.

12. A mechanism as claimed in any of claims 1 to 10 made from synthetic plastics material.

13. A mechanism substantially as hereinbefore described with reference to the accompanying drawings.

14. A vehicle trailer for use with a tractor unit comprising a projection for locking the trailer to the tractor unit and a mechanism as claimed in any preceding claim in which the mechanism and projection are substantially in line on the forward aft axis of the trailer.

15. A vehicle trailer as claimed in claim lik in which the support is fixed to the underside of the trailler and the member in the second position prevents access to projection.