GB2272194A - Vehicle coupling apparatus with locking device. - Google Patents

Abstract

A vehicle coupling apparatus 1 for vehicle couplings of the ball-and-socket type includes a body 2 having a socket 6 adapted to receive a ball member. The body 2 is provided with an integral locking mechanism which is in the locked configuration prevents the insertion of a ball member in the socket. The locking mechanism 30 may cooperate with and immobilise the catch 19, or may include a locking member which is insertable into the socket. The coupling prevents unauthorised hitching of the towed vehicle and does not require a separate locking means to be provided. <IMAGE>

Description

Vehicle Coupling Apparatus with Locking Device The invention relates to a security means for a vehicle coupling apparatus of the ball-and-socket type.

Caravans, trailers and other towable vehicles (hereinafter referred to generally as trailers) are vulnerable to theft, in part owing to the fact that they are inherently mobile. It is a simple matter to disconnect a trailer, or to take a free-standing trailer, and reconnect it to a second vehicle for removal; once the trailer is on the road it is hardly possible to identify whether the towing vehicle is legitimate or not. Consequently trailer thefts are a problem both in the private leisure sector but in particular to owners of commercial trailers, plants etc. which often have to be left on site overnight.

It is therefore essential to immobilise trailers in order to provide a measure of protection against theft, such immobilisation having effect whether the trailer is standing alone or is coupled to a stationary vehicle. Known methods include wheel clamps and other means of preventing actual movement of the trailer, for example by interfering with the ground if towing is attempted. However, such devices are cumbersome and time-consuming in application and therefore inappropriate where the trailer may need to be moved around by hand. Consequently, security apparatuses have been devised which act on the coupling apparatus so as to protect trailers from either removal from a coupled vehicle if already attached or reattachment to the towbar of another vehicle. In the latter case, minor relocation by hand is still possible while vehicular towing is prevented.

In the main, coupling apparatuses fall into two categories; the bolt and eye type (used on heavy duty commercial trailers and equipment) and the ball-andsocket type which is commonly found in use with leisure trailers, caravans etc. It is this latter type which is of concern to the present invention.

The ball-and-socket coupling is extremely simple in design. The towing vehicle is provided with a semipermanent towbar fixture having an upward facing ball attachment which is matable with a downward facing socket arrangement on the trailer. In a simple form, the socket arrangement comprises a sturdy metal body or frame having a moulded or otherwise formed socket section or coupling head. In use, the weight of the trailer tends to maintain the connection of the ball and the socket, but a spring-loaded catch mechanism is included which in its closed state acts to prevent the ball from becoming removed from the socket by engaging in the neck of the ball. Equally, when the trailer is uncoupled, this catch, when closed, prevents entry of the ball into the socket. The catch mechanism is released via a lever mechanism in order to allow connection and disconnection of the coupling.A further safety feature may be incorporated in order to prevent inadvertent operation of the lever mechanism, for example in the form of a clasp which clips over a part of the lever mechanism so as to prevent the release of the catch mechanism. Designs of ball-andsocket couplings vary principally in the arrangement of the lever and catch mechanism.

A security device is known which may be adapted to secure any design of coupling and takes the form of a lockable box which fits around and encloses the coupling regardless of type. In other words the thief is prevented from accessing the coupling. However, the box is inconvenient for the user since it must be removed and put somewhere when the coupling is to be engaged or disengaged.

Some more complex designs of ball-and-socket couplings have security devices specifically designed for them and act in the main by locking the lever mechanism used to open the catch mechanism of the socket arrangement. In more simple arrangements, this effect is most commonly achieved by using a padlock. A hole is machined through the frame of the socket arrangement and through a part of the lever mechanism so as to be continuous when the catch is in its closed position. The pin of a padlock may then be inserted through the hole so as to immobilise the lever mechanism, thereby preventing the release of the catch mechanism. However, even this presents some inconvenience to the user since while the catch is to be withdrawn the padlock must be taken off and put somewhere, with the consequent risk that it is lost in the process.

An aim of the present invention is therefore to provide an alternative to the above arrangements in providing an efficient and convenient way of immobilising a coupling apparatus for vehicles.

According to the present invention there is provided a coupling apparatus for vehicle couplings of the ball-and-socket type, including a body member having a socket adapted to receive the ball member and a catch movable so that at one limit of movement it partially obstructs the head opening in order to engage the neck of the ball member and close the coupling; wherein the coupling apparatus is provided with an integral locking mechanism to prevent the insertion of the ball member into the socket.

A coupling apparatus incorporating a security device in accordance with the present invention presents a number of advantages over the known combinations of devices currently available for preventing an unattached trailer from being attached to an unauthorised vehicle for towing. A robust heavyduty lock is provided, which is permanently attached to the trailer and is therefore both convenient and safe.

Furthermore, the lock itself is more secure than an external attachment such as a padlock because there are no obvious sites at which a forced entry might be attempted.

It is intended that reference to an integral locking mechanism implies that the mechanism is effectively permanently attached to the coupling apparatus. It is envisaged that the locking mechanism might be cast in the body of the apparatus or in other embodiments might be welded on or even securely bolted on to the body.

One possibility for making the lock operable to prevent the ball member from entering the socket would provide the locking mechanism with a locking member or pin which is extendable into the socket so as to prevent entry of the ball. In this case, the mechanism might be located in the socket region.

It is envisaged that in an advantageous embodiment the locking mechanism, including a locking member or pin, might be operable to disable the catch of the coupling apparatus so that the socket is blocked; most simply this could be effected by retaining the catch in its obstructed position so as to either prevent removal from or entry into the socket of a ball member. In such an arrangement the coupling apparatus might be constructed so that apertures are formed in the body member and the catch so as to be continuous when the catch is in its obstructing position. The locking mechanism is located so that the locking member enters the aperture, thereby preventing the release of the catch. This has the advantage of preventing both disconnection from and reattachment to a towing vehicle. Additionally, the locking pin of the locking mechanism might be springloaded or otherwise biased so as to rest in the unlocked position. However other versions might have no biasing or indeed might be biased into the locked position.

The invention will be illustrated further in the following description of an embodiment with reference to the accompanying drawings, in which; Fig. 1 shows a sectional side view of a coupling apparatus in accordance with the present invention, Fig. 2 shows a section through the line A-A in the direction shown in Fig. 2.

With reference to Figs. 1 and 2, a specific embodiment in accordance with the present invention of a trailer attachment of a vehicle coupling apparatus having a security means is shown, most parts of which are of conventional construction.

The coupling apparatus (trailer section), shown generally at 1, essentially comprises a body 2 constructed from steel, or possibly another rigid and durable material, and adapted to be secured, for example by bolts, to the frame or chassis of a trailer.

At the end of the coupling apparatus 1 remote from the trailer, the body 2 has a coupling head 4 in which a substantially spherical socket 6 is defined. The socket 6 is of such dimensions as to receive the ball connector of a conventional towbar.

The upper part of the coupling head 4 is provided with raised longitudinal bar sections 8, 9 which extend in parallel with the axis of the coupling apparatus 1 and which define a channel 11. The channel 11 communicates with the socket 6 via a connecting passage 13. The raised sections 8, 9 are provided at one end with co-axial bores 10 and are each further provided with apertures in the form of co-axial through-bores 15.

The coupling apparatus is further provided with a catch mechanism, shown generally at 17, which comprises a handle 19 and an arm 24. The handle 19 is provided with a grip 20 by which the catch may be actuated and rests in the channel 11 so that the grip 20 is accessible. The handle 19 has a bore 21 which is continuous with the bores 10 in the raised sections 8, 9 when the coupling apparatus is assembled so that on application of a bolt through the bores 10, 21, a pivot point is formed around which the catch mechanism may turn.

The arm 24 of the catch mechanism 17 extends from the end of the handle remote from the pivot point, through the connecting passage 13 and into the socket 6 to form a lip 26.

The dimensions of the arm 24 and the connecting passage 13 are such that the catch mechanism 17 may be rotated around the pivot point between two limits of movement. At one limit, i.e. when the handle 19 rests in channel 11, the lip 26 extends into the opening 7 so as to prevent entry or removal of a ball. In the resting or closed state of the catch mechanism the handle 19 sits in channel 11 by virtue of the influence of gravity. However in conventional coupling apparatuses the catch mechanism normally will include a biasing means (not shown), for example in the form of a spring which tends to retain the catch mechanism in its obstructing position. When the handle 19 is lifted against the resistance of such a biasing means so as to rotate the catch mechanism 17, the lip 26 is retracted sufficiently to allow passage of the ball.

The handle 19 also has an aperture 22 which in the resting or closed state of the catch mechanism corresponds to and lines up with the apertures 15 in the raised sections 8, 9 of the coupling head 4.

In addition to the inclusion of a spring means adapted to resist retraction of the lip of the catch mechanism, additional security devices such as clasps may be provided which can be clipped over the handle when the coupling apparatus is coupled with a ball member so as to prevent inadvertent lifting of the handle.

The coupling apparatus in accordance with the invention includes a locking device 30 (shown in a half-way position in Fig.2) which is housed in an extension 32 in one side of body 2. The locking device 30 comprises a locking mechanism including a lock pin or bar 34 which is located in and slidable in the aperture 15 in the one raised section 8 (on one side of the body 2) and through the corresponding aperture 22 in the handle means 19. The pin 34 can travel between a position in which it is retracted into the raised section 8 and extension 32, and a position in which it passes through the aperture 22 in the handle 19 into the bore 15 in the raised section 9. In the unlocked state, the pin 34 is held in the retracted position so as to be retracted from the aperture 22 in the handle 19 in order that the catch mechanism 17 may move freely between its limits of movement.In the locked state, the pin 34 is held in position so as to extend through the aperture 15 of the raised section 8 and into the handle aperture 22 and the aperture 15 of the raised section 9, thereby preventing movement of the handle 19 and retaining the catch mechanism 17 in a position where the lip 26 of the arm 24 partially obstructs the opening 7 of the socket 6 and prevents entry or removal of a towbar ball.

The above coupling apparatus has been described with the locking device 30 housed within an integral extension 32 of the frame 2. It is envisaged that the locking device 16 might equally be contained in a unit which is welded or otherwise permanently attached to the basic body 2. A replaceable lock would be acceptable if proof against theft when in the locked state.

In the present embodiment the coupling apparatus has been described as having apertures 15 in both raised sections 8 and 9. It would be possible to provide an aperture only on the side of the frame bearing the lock. In such an arrangement the use of a locking mechanism having a shorter pin might be appropriate, the pin in such an apparatus extending only through the raised section 8 and the handle means 19 in the locked position. Alternatively an aperture might be provided in the raised section on the side of the frame bearing the lock, and a blind hole in the other raised section. In this arrangement the locking member in the locked position might extend through the apertures in the one raised section, the catch and into the blind hole in the other raised section.Both arrangements offer a more secure means of preventing theft of a trailer in that the locking member at no time extends beyond the confines of the lock housing or the body of the coupling apparatus and therefore is not vulnerable to forcing.

It is envisaged that, in one embodiment, in the unlocked state of the locking device the pin might protrude outside the locking device 30 as an indication that the apparatus is not secured. Actuation of the locking device might be effected in a number of ways.

In one embodiment, where in the unlocked state the pin extends outside the locking device, actuation of the lock might involve physically pushing the pin into the housing of the device. Alternatively, the turning of a key might be used to physically insert the pin whereupon the pin is held in the locked position by a releasable catch. Preferably the pin of the locking device is springloaded so as to rest in the unlocked position, a positive closing action being required in order to lock it. In other embodiments however it might be advantageous to provide a pin springloaded so as to rest in the locking position.

The pin 34 may be locked in position in any conventional way, for instance by the use of a conventional key or even a combination code.

Claims (8)

Claims:

1. A coupling apparatus for vehicle couplings of the ball-and-socket type including a body having a socket adapted to receive a ball member and a catch movable so that at one limit of movement it partially obstructs the socket in order to engage the neck of the ball member and close the coupling, wherein the body of the coupling apparatus is provided with an integral locking mechanism which in the locked configuration prevents the insertion of the ball member into the socket.

2 A coupling apparatus according to claim 1 wherein the locking mechanism is permanently attached to the outside of the body.

3. A coupling apparatus according to claim 1 wherein the locking mechanism is housed within the body member.

4. A coupling apparatus according to any preceding claim wherein the locking mechanism includes a locking member which is insertable into the socket so as to prevent movement of a ball member into or out of the socket.

5. A coupling apparatus according to any one of claims 1, 2 or 3 in which the locking mechanism includes a locking member which is adapted to interact with and immobilise the catch.

6 A coupling apparatus according to claim 5 in which the locking member is adapted to project through an aperture formed in the catch and through a corresponding aperture formed in the body member.

7. A coupling apparatus according to any one of claims 4, 5 or 6 in which the locking member is spring loaded.

8. A coupling apparatus substantially as described herein with reference to the accompanying Figures 1 and 2.