GB2240076A

GB2240076A - Security device for an articulated lorry

Info

Publication number: GB2240076A
Application number: GB9101269A
Authority: GB
Inventors: Archibald Grant
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-01-19
Filing date: 1991-01-21
Publication date: 1991-07-24
Also published as: GB9101269D0

Abstract

A king pin 3, 4, 5 is normally fixed to the underside of an articulated lorry carriage for locking with a fifth wheel coupling of the corresponding lorry cab. The lorry carriage could be stolen if the fifth wheel coupling of a third party's lorry cab is locked onto the king pin 3, 4, 5 of the carriage. To prevent this a lockable annular clamp of the invention hinged into two halves is clamped round the king pin 3, 4, 5, with a narrower waist portion 11a clamping onto the waist of the king pin 3 while the upper and lower enlarged ends of the clamp 9a, 10a respectively clamp round the upper bearing plate 4 and lower flange 5 of the king pin. In this way the waist of the king pin 3 is larger and can no longer fit into the key hole formation of a fifth wheel coupling. <IMAGE>

Description

Security Device for an Articulated Lorrv This invention relates to a security device preventing coupling of the king pin of an articulated lorry carriage with a lorry cab. More particularly the security device is used to deter theft or illegal parking of the lorry carriage.

On long goods hauls the driver of an articulated lorry will often unhitch his locked carriage and leave it in a lay-by or parking lot over night while he takes the lorry cab to a hotel.

Even though the lorry carriage is bolted up, unscrupulous persons will still hitch up the carriage up to another lorry cab and drive it to a secluded spot where they can then break open the carriage and pilfer its contents.

It is an object of the present invention to obviate or mitigate this problem.

The invention has approached the solution to this problem by looking at the king pin and fifth wheel coupling which connect the carriage of the articulated lorry to the cab thereof. The king pin, which is bolted to the front underside of the carriage has a narrow waist with an upper bearing plate bolted to the carriage and a flanged lower end. The fifth wheel coupling is a circular type plate and has a key-hole shaped slot cut therefrom into which the waist of the king pin slides to lock the lorry carriage and cab together.

The present invention lies in a security device connectable to the king pin of an articulated lorry carriage to disfigure the waist thereof and thereby prevent insertion of said waist into the fifth wheel coupling of a lorry cab.

The disfigurement of the king pin could be realised in a number of ways, as long as the definite shape required for insertion into the fifth wheel coupling is disrupted. For example a clamp/lockable vice could be clamped onto the bottom flange of the king pin thereby extending towards the waist and preventing said coupling operation. Other clamp designs fixed to the flanged ends of the pin may be hinged to pivot symmetrically and close round the circumference of the king pin. Another embodiment of the invention is a device (one piece or lockably hinged in eg. two parts) having an annular core into which pawls are extendable radially. The device would be pushed axially over the lower flange of the king pin and then the pawls extended to prevent coupling as aforesaid with the waist of the king pin.

Most preferably the security device is in the form of a clamp hinged into at least two parts and which when closed define by their inner walls a through extending opening, said device including a waist portion having an inner diameter opening substantially corresponding to that of the king pin and locatable between the lower flange and the upper bearing plate of the king pin.

Advantageously the waist portion is locatable neatly between said lower flange and upper bearing plate of the king pin.

In one embodiment the inner walls of the waist portion are sprung radially inwardly and are pushed up over the lower flange of the king pin to locate at the waist of the king pin. The waist portion of the device once sprung inwardly cannot then be pulled back over the larger lower flange, but would be hinged in say two parts to allow removal.

In a preferred embodiment the hinged parts thereof are separable to locate onto the king pin.

Preferably also, the security device includes enlarged ends adjacent either end of the waist portion of said device for locating over the upper bearing plate and lower flange of the king pin.

The clamp could either grip the waist and be supported frictionally, or could be sufficiently slack to rotate on the waist and be supported by the lower flange of the king pin, so long as it cannot be pulled thereover. There could therefore be a range of sizes for the inner diameter of the clamp.

The invention will now be described by way of example only with reference to the accompanying drawings in which: Fig. 1 - is a schematic drawing of an articulated lorry carriage and cab connected by a king pin and fifth wheel coupling; Fig. 2 - is an enlarged schematic drawing of the king pin and fifth wheel coupling shown in Fig. 1; Fig. 3 - is a front view of an upright clamp in accordance with the invention; Fig. 4 - is a plan view of the clamp shown in Fig. 2; and Fig. 5 - is a section through A - A of Fig. 4.

The carriage 1 of an articulated lorry is attached to the cab 2 of the lorry by a standard fixing: a king pin 3, 4 and 5 and fifth wheel coupling 6. This king pin is I-shaped viewed from the side, and comprises a vertical rod like waist 3 connecting a top bearing, and bottom flange 4 and 5, and is bolted onto the front underside of the carriage 1 via the top bearing flange 4. The fifth wheel coupling 6 which, is in the form of a circular platewith a key-holed shaped opening cut therefrom, extends from the rear upper surface of the lorry cab 2 and receives the waist of the king pin 3 into the centre of keyholed shaped opening thereby coupling the lorry carriage 1 and cab 2 together.

In accordance with the invention a circular clamp 7a ad 7b is provided comprising two symmetrical halves connected by hinges 8 to open and close around the waist 3 of the king pin thereby to prevent the carriage 1 coupling with the lorry cab 2 as aforesaid.

Each half 7a or 7b of the clamp as shown in Fig. 5 is semicircular having a planar inner surface and a clamping recess extending from the top to the bottom along the middle lines of said inner surface. The clamping recess has enlarged first upper and lower ends 9a and 10a having a radius slightly larger than that of the respective upper and lower flanges of the king pin, and a narrower waist lia recess communicating with said first upper and lower recesses and defined by an inwardly extending first semi-circular ridge 12a having first upper and lower shoulders 13a and 14a. The waist recess 11 has a radius corresponding to that of the king pin waist 3.Two other through extending recesses which are provided symmetrically about the centre line of each half, are semi-bolt shaped and have respective second upper, lower enlarged ends 15a and 16a communicating with a middle recess 17a for receiving the locking nut, head and shank of a bolt (not shown). Second upper and lower shoulders 18a and 19a spaced by a second inwardly extending ridge 20a similarly define the base of the second enlarged ends 18a and 19a.

When the two halves 7a and 7b are closed as shown in Fig. 4, the two clamping recesses define a through extending annular opening 9a, 10a, lia and 9b, 10b lib having an upper/lower, and middle diameter corresponding respectively to that of the flanges 4 and 5, and waist 3 of the king pin. Two bolts receiving through openings 15a, 16a, 17a and 15b, 16b, 17b are also defined on either side of this clamping opening.

In use the clamp 7a, 7b is opened and closed around the king pin in a similar fashion to that of a female mould whereby the respective inner and outer surfaces of the clamp 7a, 7b and king pin conform with one another. The clamp 7a and 7b is thereby supported by the first lower shoulders 14a, 14b of the first ridges 12a, 12b and which in turn rest on the lower flange 5 of the king pin.

In this way the ridges 12a, 12b of the clamp 7a, 7b disfigures the waist 3 of the king pin preventing it from being inserted into the key-hole opening of the fifth wheel coupling 6 and thereby preventing the lorry carriage from being hitched up and stolen.

Bolts (not shown) are then inserted into the bolt shaped through opening 15a, 16a, 17a and 15b, 16b, 17b and the two halves of the clamp 7a and 7b locked together by a nut (not shown) which locks down against the second upper shoulders 18a and 19b and tensions the bolt head against the second lower shoulders 19a and 19b of the second ridge 20a and 20b.

Alternatively locking means, for example a barrel lock, could be used in place of the bolts described hereabove.

Finally, as best shown in Fig. 3, an annular groove 21a, 21b is provided on the outer periheral surface of each half of the clamp 7a, 7b. This groove 21a, 21b provides a finger grip for closing the clamp round the king pin. The groove 21a 21b can also act to receive a steel band or chain (not shown) which can then be padlocked at its free end to provide.further security.

Although the security device 7a, 7b of the invention has been described hereabove as an anti-theft device, it could also act in a similar way to a wheel clamp, to clamp illegally parked lorry carriages.

Claims

1. A security device connectable to the king pin of an articulated lorry carriage to disfigure the waist thereof and thereby prevent insertion of said waist into the fifth wheel coupling of a lorry cab.

2. A security device as claimed in claim 1 which is in the form of a lockable clamp hinged into at least two parts, and which when closed define by their inner walls an through extending opening, said device including a waist portion having an inner diameter opening substantially corresponding to that of the king pin, and locatable between the lower flange and upper bearing plate of the king pin.

3. A security device as claimed in claim 2 wherein the waist portion is locatable neatly between said lower flange and upper bearing plate of the king pin.

4. A security device as claimed in claims 2 or 3 wherein the inner walls of the waist portion are sprung radially inwardly and are pushed up over the lower flange of the king pin to locate at the waist of the king pin.

5. A security device as claimed in claim 2 or 3 wherein the hinged parts thereof are separable to locate onto the king pin.

6. A security device as claimed in any preceding claim which includes enlarged ends adjacent either end of the waist portion of said device for locating over the upper bearing plate and lower flange of the king pin.

7. A security device as claimed in any preceding claim which has an annular groove on its outer surface, sufficiently large to receive a band or chain.

8. A security device as claimed in any preceding claim wherein adjacent the waist portion is provided two locking bolt holes, each bolt hole having a symmetrical portion on each part of the security device.

9. A security device substantially as described with particular reference to Figs. 3 to 5.