GB2277308A

GB2277308A - A trailer towing hitch locking device

Info

Publication number: GB2277308A
Application number: GB9308089A
Authority: GB
Inventors: Barry Higginson
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-04-20
Filing date: 1993-04-20
Publication date: 1994-10-26
Also published as: GB9308089D0

Abstract

A towing hitch locking device for preventing the theft of a trailer having a towing bar (10) and towing the device ring (11), comprising a sleeve (14) slidably engageable loosely over the towing bar (10), and a housing member (15) having a central boss welded thereto and capable of being screwed down onto a threaded rod on the top of the post (12). By engaging the towing ring (11) of the trailer on the boss (16) within the housing member (15) and then sliding sleeve (14) over housing member (15) and finally actuating a push button lock on the base of sleeve (14) thus to engage within an aperture in the base of housing member (15), the entire device is locked, and access to the towing ring (11) is prevented until the push button lock is released. By locating the housing member (15) on the top of the upright post (12) the trailer may be locked and maintained in a level condition. <IMAGE>

Description

A TRAILER TOWING HITCH LOCKING DEVICE THIS INVENTION concerns a locking device for the towing hitch of a trailer and is particularly, though not exclusively, concerned with the kind of towing hitch usually provided on mechanical plant and comprising, on the end of a towing bar forming part of the trailer, a ring of generally toroidal shape usually arranged such that its central aperture has its axis vertical thus to be located upon a vertical pin fixed to the rear of a towing vehicle.

When mechanical plant is left unattended it must be secured to prevent it from being moved by unauthorised personnel, and in many case such plant is mounted on a single axle and requires jacks to maintain it level. Preferably therefore the locking device of the present invention is intended to enable the trailer to be fixed to a hitching post of appropriate height.

An object of the present invention is to provide a towing hitch locking device for trailers, which may be applied with or without the use of a hitching post in order to secure the equipment against theft or unauthorised use.

According to the present invention there is provided a towing hitch locking device for trailers, comprising a first housing member slidably engageable as a loose sleeve onto a towing bar, a second housing member for engagement with the towing hitch and adapted to receive the first housing member, and locking means to prevent separation of said first and second housing members, and consequently of said second housing member from the towing hitch.

An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings, in which:- Fig. 1 is a vertical part-sectional elevation of the device made in accordance with the invention; Fig. 2 is a vertical section taken on line II-II of Fig. 1; and Fig. 3 is an isometric view of the device when opened.

The locking device to be described is intended to be applied to the towing hitch of a trailer, for example, an item of mechanical plant mounted on a wheeled axle for transportation. Such equipment may comprise a towing bar 10 upon the free end of which is welded a ring ii of generally toroidal form and arranged with its central aperture axially vertical to be located, for towing, on a vertical pin fixed to the rear of a vehicle.

A locking device is provided, in accordance with the invention, to mount the towing bar 10, in a locked condition, on an upright post 12. For this purpose, the top of the post 12 is provided with an upright threaded rod 13.

The locking device comprises a first housing member in the form of a generally rectilinear open-ended sleeve 14 which is slidably engageable as a loose fit over the towing bar 10. A second housing member 15 has a base, three side walls and an open end, and has welded within the base an internally threaded boss 16. The aperture in the boss 16 is aligned with a slightly larger aperture 17 in the base of the housing member 15. Therefore, the housing member 15 may be screwed down onto the post 12 by engagement of the boss 16 onto the rod 13.

Once the second housing member 15 is fixed onto the post 12, the trailer may be advanced to locate the ring 11 over the boss 16 as can be seen clearly in Fig. 3. Finally, the first housing member 14 is advanced along bar 10 into position over the second housing member 15 to the position illustrated in Fig. 1.

A push button lock 18 is provided on the base of the first housing member 14 and has a pin 19 which locates within an aligned aperture 20 in the base of the second housing member 15.

It will be seen from Fig. 1 that the base 21 of the first housing member 14 extends only part way along the latter thus to provide a clearance with the adjacent face of post 12.

Once the device is locked there can be no separation of the housing members 14 and 15 or of the housing member 15 from the towing hitch. This locked condition prevails whether or not the device is mounted on the post 12. Therefore, the device may be used with or without the post to prevent access to the towing hitch until the push button lock 19 is released. However, when used with the post 12 the trailer is locked to the latter and maintained in a level condition.

Preferably, the major parts of the device are constructed from welded steel or aluminium plate or from a rigid plastics material.

Claims

1. A towing hitch locking device for trailers, comprising a first housing member slidably engageable as a loose sleeve over a towing bar of a trailer, a second housing member for engagement with the trailer towing hitch and adapted for engagement with the first housing member, and locking means to prevent separation of the first and second housing members, and consequently of said second housing member from the trailer towing hitch.

2. A towing hitch locking device according to Claim 1, wherein the first housing member is provided in the form of a generally rectilinear open-ended sleeve and the second housing member includes a base plate having an upstanding boss fixed thereto to become engaged with the trailer towing ring, the locking means enabling the first and second housing members to be secured together to prevent separation of the towing ring and the boss.

3. A towing hitch locking device according to Claim 1, wherein the second housing member has a base plate, three side walls and an open end and has welded to the base plate an internally threaded boss 16, there being aligned bores in the boss and in the second housing member, adapted to receive a threaded rod on a fixed post such that the second housing member may be screwed down onto the post by engagement of the boss onto the threaded rod.

4. A towing hitch locking device according to Claim 1, wherein said locking means is a push button lock mounted on the first housing member and having a pin which when the lock is actuated, engages within an aperture in the second housing member.

5. A towing hitch locking device according to Claim 1, wherein said first housing member has a base extending only part way along the latter to provide clearance between the base and the adjacent face of a post to which the second housing member is attached.

6. A towing hitch locking device for trailers, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.