GB2221881A

GB2221881A - Security device

Info

Publication number: GB2221881A
Application number: GB8816040A
Authority: GB
Inventors: Graham Stokes; Carolyn Ann Stokes
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-07-06
Filing date: 1988-07-06
Publication date: 1990-02-21
Also published as: GB8816040D0

Abstract

A security device comprising a rigid metal housing 15 open at one face 16 to permit introduction into the housing of the coupling hitch component 11 of a towable unit, such that while the component is retained within the housing 15 access to the component for coupling to a mating component is prevented, releasable locking means (25) for preventing withdrawal of the coupling component from the housing, and internal guide means (23, 24) in the housing for co-operation with the coupling hitch component introduced therein to achieve a predetermined alignment of the housing relative to the coupling component. <IMAGE>

Description

" SEC URI TY DEVICE" This invention relates to a security device for use with towable units including caravans and trailers.

A towable unit includes one component of a coupling hitch the mating component of which is secured to the towing vehicle. Theft of towable units, notably caravans, is becoming much more prevalent, and it will be recognised that it is a relatively simple matter for an unauthorised person to couple the towable unit to his own towing vehicle and then to tow the unit away.

It is an object of the present invention to provide a security device whereby, in a simple and convenient form, the risk of an unauthorised person coupling his own towing vehicle to the coupling component of the towable units, is minimised.

In accordance with the present invention there is provided a security device comprising a rigid metal housing open at one face to permit introduction into the housing of the coupling hitch component of a towable unit, such that while the component is retained within the housing access to the component for coupling to a mating component is prevented, releasable locking means for preventing withdrawal of the coupling component from the housing, and internal guide means in the housing for co-operation with the coupling hitch component introduced therein to achieve a predetermined alignment of the housing relative to the coupling component.

Preferably said releasable locking means includes an elongate metal pin which, in an operative position, extends transverse to the direction of alignment of the coupling member and the housing, the ends of the pin, in the operative position, co-operating with opposite walls of the housing and the pin, intermediate its ends, co-operating with the coupling hitch component to prevent withdrawal of the coupling hitch component from the housing.

Preferably the releasable locking means also includes a key operated locking mechanism for retaining said pin in its operation position relative to the housing.

Desirably said guide means includes a channel formation within the housing, said channel formation extending at right angles to said pin and co-operating, in use, with a part of said coupling hitch component to ensure that said coupling hitch component is disposed, in use, at right angles to said pin.

One example of the invention is illustrated in the accompanying drawings wherein Figure 1 is a perspective view, partly broken away, of a security device, and Figure 2 is a side elevational view, partly in section, of the device fitted to a coupling hitch component.

Referring to the drawings, the security device which is illustrated is intended for use with a ball hitch coupling of the wBradleyw type although it will be appreciated that with minor dimensional changes a device could be produced for co-operation with a variety of different coupling hitch components. As is apparent from Figure 2 the wBradleyw type ball hitch comprises a casting 11 adapted at one end 12 to be bolted to the draw-bar of a towable unit, for example a caravan or a trailer. At its opposite end the casting 11 defines an aperture 13 for receiving the towing ball of a towing vehicle.Associated with the recess 13 is a latch mechanism for retaining the towing ball within the recess and pivotally mounted on the casting is a metal handle 14 movable relative to the casting to release said latch mechanism and permit disengagement of the coupling hitch component defined by the casting 11 from the mating coupling hitch component constituted by the towing ball of the towing vehicle. The handle 14 is, as can be seen from Figure 2, a closed loop.

The handle is spring urged to a rest position, and can be retained in the rest position by a releasable retainer. Such a ball hitch arrangement is well known and is customarily referred as a wBradley"-type ball hitch.

The security device comprises a rigid metal housing 15 in the form of a rectangular box having one end wall omitted. Thus the housing has an open end 16, an opposite, closed end 17, a top wall 18 and an opposite base wall 19, and opposite side walls 21, 22. Rigidly secured to the inner surface of the top wall 18, and extending along the centre line of the top wall 18 from the open end 16 towards the closedend 17 is guide member 23 in the form of a rigid metal channel having its base secured to the top wall 18 of the housing. The open face of the channel is presented towards the base wall 19 of the housing and the inner end of the channel is closed by an abutment 24 welded to or integral with the member 23. The width of the channel constituting the guide member 23 is such that the handle 14 of the ball hitch coupling component can be received therein.Thus engagement of the housing with a coupling involves introducing the free end of the coupling component into the open end 16 of the housing such that the handle 14 is received within the guide 23. The housing is then slid onto the coupling component until the abutment 24 abuts the handle 14 and/or the casting 11. In this position of the housing relative to the coupling component access to the recess 13 is prevented as is manipulation of the handle 14 relative to the casting 11. Thus provided that the housing remains in place on the coupling component the coupling component cannot be engaged with a mating towing ball.

In order to secure the housing to the coupling component there is provided a locking arrangement including a cylindrical, hardened steel, locking pin 25 of substantial thickness. The pin 25 is conveniently attached to the housing 15 by means of a chain 26 so that the pin 25 is not lost when in an inoperative position. The side walls 21, 22 of the housing are each formed with an aperture 27 through which the pin 25 can extend, the apertures 27 being aligned so that when the pin 25 is received thereby, the axis of the pin 25 lies at right angles to and intersects the elongate guide member 23. As is apparent from Figure 1 the side walls of the guide member 23 are formed with apertures 28 to accommodate the pin 25.A short cylindrical collar 29 is welded to the exterior of the wall 22 around the aperture 27 and has an internal diameter equal to that of the aperture 27 so as to be capable of slidably receiving the pin 25.

Welded to the outer face of the wall 21 and overlying the aperture 27 in the wall 21 is a lock housing 31. The lock housing 31 is a rigid structure which receives a key operated locking mechanism for retaining the pin 25 in an operative position. Adjacent one end the pin 25 has a circumferentially extending groove 32 and the axial length of the pin 25 is so arranged that when the pin is inserted through the apertures 27 so that the end of the pin remote from the groove 32 lies flush with the end of the collar 29 then the end region of the pin 25 carrying the groove 32 is received within the lock housing 31 so that a locking element, operated by the key operated mechanism within the housing 31, can engage in the groove 32 to prevent withdrawal of the pin 25.As is apparent from Figure 2 the pin 25, in its operative position, passes through the loop handle 14 of the coupling component adjacent the end thereof and thus prevents withdrawal of the coupling component from the housing.

When it is desired to free the coupling component for use the key operated lock is released by means of the appropriate key so freeing the pin 25 for transverse withdrawal from the apertures 27.

Thereafter the coupling component can be withdrawn longitudinally from the housing 15. The guide means 23 ensures that the housing is engaged on the coupling component in a predetermined alignment such that the longitudinal axis of the coupling component is transverse to the axis of alignment of the apertures 27.

It will be recognised that when the housing 15 is locked in position on the coupling component it is virtually impossible to remove the housing without access to the appropriate key. The pin 25 is wholly protected by the housing 15, the collar 29 and the lock housing 31 and the only access to the interior of the housing is obstructed by the coupling component itself. Even if a saw or similar cutting tool could be introduced through the end 16 of the housing then it would be virtually impossible to saw through the hardened pin 25 since by virtue of the circumferential nature of the groove 32, the pin 25 is free to rotate while locked axially in position.

It is convenient to manufacture the housing 15 by cutting a predetermined length from an elongate, rectangular, steel tube, the end 17 of the housing 15 then being provided by welding a steel blanking plate to one end of the cut length of tube.

Claims

CLAIMS.

1. A security device comprising a rigid metal housing open at one face to permit introduction into the housing of the coupling hitch component of a towable unit, such that while the component is retained within the housing access to the component for coupling to a mating component is prevented, releasable locking means for preventing withdrawal of the coupling component from the housing, and internal guide means in the housing for co-operation with the coupling hitch component introduced therein to achieve a predetermined alignment of the housing relative to the coupling component.

2. A device as claimed in claim 1 wherein said releasable locking means includes an elongate metal pin which, in an operative position, extends transverse to the direction of alignment of the coupling member and the housing, the ends of the pin, in the operative position, co-operating with opposite walls of the housing and the pin, intermediate its ends, co-operating with the coupling hitch component to prevent withdrawal of the coupling hitch component from the housing.

3. A device as claimed in claim 2 wherein the releasable locking means also includes a key operated locking mechanism for retaining said pin in its operation position relative to the housing.

4. A device as claimed in any one of claims 1 to 3 wherein said guide means includes a channel formation within the housing, said channel formation extending at right angles to said pin and co-operating, in use, with a part of said coupling hitch component to ensure that said coupling hitch component is disposed, in use, at right angles to said pin.

5. A device as claimed in any one of claims 1 to 4 wherein said pin, in its operative position, intersects said guide means.

6. A security device substantially as hereinbefore described with reference to the accompanying drawings.