Fork-lift trucks which are required to work outdoors need means to protect the driver from adverse weather.

Many fork-lift trucks are provided with a full cab including an automotive type door on at least the driver's side. The doors are usually hinged at the front with an adjustable window in the doorframe. Such doors are costly to build and require considerable space to open and shut the door which can be a problem, particularly in congested stock yards.

It is also well known to provide enclosures consisting of flexible woven or plastic material with transparent panels and incorporating material such as Velcro and fasteners to secure to the truck body. Generally the access door of such enclosures is opened and secured by zip fasteners, which are generally inconvenient. When the door is to be kept open, the door usually has to be rolled up and secured at the roof. This type of enclosure generally restricts driver visibility.

The present invention has been made from a consideration of the above mentioned disadvantages and, in particular, in order to provide an improved screen assembly and enclosure assembly for a fork-lift truck which overcomes one or more of the problems associated with known enclosures.

Thus, the present invention aims to provide a simple, low cost screen assembly and enclosure assembly, which can be added to new fork-lift trucks at manufacture or can be retrofitted to existing fork-lift trucks and which do not restrict driver visibility.

Advantageously, the screen assembly of the invention provides weather protection for the driver.

According to the present invention there is provided a screen assembly for a fork-lift truck comprising first and second mutually spaced apart rail members; at least one protective panel member provided between the first and second rail members, the at least one panel member and the first and second rail members together defining a doorway ; and at least two interengagable doors slidably coupled between the first and second rail members and arranged for slidable movement between an open state, in which the doorway is open; and a closed state, in which the doorway is closed.

Preferably, the sliding doors are arranged in side by side relationship on one side of the protective panel.

Thus, preferably, the doors comprise a side door located adjacent one side of the screen assembly and a central door located between the protective panel and the side door.

Preferably, the doors are assembled such that, when the side door is moved to the closed position, it engages the central door, causing the central door to close and thereby fully closing the doorway. Similarly, preferably when the side door is moved to the open

position, it engages the central door, causing the central door to open and thereby fully opening the doorway. Preferably, engagement means is provided on one of said doors for engaging an abutment on the other of said doors.

Preferably, the or each door is coupled to at least one of the first and second rail members by a roller and roller guide assembly. Preferably, the door is coupled to at least one of the first and second rail members by a runner and runner guide assembly.

Preferably, the protective panel and doors are releasably connected to the first and second rails to facilitate replacement of damaged panels. The protective panel may comprise a frame carrying a sheet of protective material.

Alternatively, in order to reduce the effective width, the protective panel may comprise a single sheet of protective material. Typically, the sheet comprises a transparent, plastics material.

Preferably, the screen assembly comprises means for pivotally securing the screen assembly to a fork-lift truck. Preferably, the screen assembly comprises means for releasably securing the screen assembly to a fork- lift truck. Preferably, such pivotal and/or releasable securing means is provided on said protective panel member.

The invention further provides an enclosure assembly for a fork-lift truck comprising a screen assembly of

the invention and a corresponding opposite side wall section, each adapted for connection to a fork-lift truck and arranged so that, when so connected, the enclosure assembly serves to shield the cabin area of the fork-lift truck from the external environment. The corresponding opposite side wall section may comprise a screen assembly of the invention or a series of fixed panels.

A front windscreen may be provided and a transparent panel may be bolted or screwed to the rear of the overhead driver protection structures of the fork-lift truck. Similarly, a roof panel may be attached above or under the overhead protection grill. Thus, the enclosure assembly of the invention may fully enclose the cabin area of a fork-lift truck.

The invention will now be described further by way of example only with reference to the accompanying drawings in which: Fig. 1 is a side view of a screen assembly of the invention as applied to a fork-lift truck; Fig. 2 (a) is a side view of the screen assembly of Figure 1 fitted to a fork-lift truck, with the doors in the fully closed state; Fig. 2 (b) is a side view of the screen assembly of Figure 1 fitted to a fork-lift truck, with the doors in the fully open state;

Fig. 3 is a cross-sectional view of the screen assembly of Figure 1, showing the door suspension arrangement; Fig. 4 is a side view of the screen assembly of Figure 1 fitted to a fork-lift truck, with the assembly in the hinged open position; Fig. 5 (a) is a plan view of the sliding door arrangement of the screen assembly of Figure 1, with the doors in the fully closed state; Fig. 5 (b) is a plan view of the sliding door arrangement of the screen assembly of Figure 1, with the doors in the partially open state; and Fig. 6 is a cross-sectional view of the screen assembly of Figure 1, showing the lower rail arrangement.

Referring to the drawings, a conventional fork-lift truck 2 comprises an overhead driver protection structure 4 around the cabin area of the truck. A screen assembly of the invention 1 is adapted to be secured to the fork-lift truck, typically to such overhead protection structure 4.

The screen assembly 1 comprises upper and lower rail members 6,8 and a protective panel member 10 provided between the upper and lower rail members. The panel member 10 and the upper and lower rail members 6,8 together define a doorway 12 which may be spanned by a side door 14 located adjacent one side of the screen assembly and a central door 16 located between the panel member 10 and the side door 14.

Each of the doors and the panel member may comprise a frame carrying a sheet of protective material.

Referring to figure 1, the screen assembly is typically shaped and dimensioned to fit the side of a fork-lift truck cabin area. The panel member 10 extends partway between the upper and lower rails and is fixed relative to the rails. The side door 14 is suitably shaped to correspond to the side of the overhead protection structure 4.

Referring to figure 2, the doors 14,16 are slidable relative to the upper and lower rails 6,8 and the panel member 10, between a fully closed state as shown in figure 2 (a) wherein the doors span the doorway 12 and a fully open state as shown in figure 2 (b) wherein the doors are substantially clear of the doorway 12.

When in the fully open state, the side door 14 overlies the central door 16 which in turn overlies the panel member 10. Typically, suitable means, such as a lock or catch mechanism, is provided to retain the sliding doors in the fully open and fully closed state.

The sliding door suspension arrangement is shown in figure 3. The upper rail 6 is secured to the upper limb of the overhead protection structure 4 and comprises a pair of roller guide assemblies or channels 18 for receiving corresponding rollers 20 provided on each door 14,16.

Thus, each door 14,16 is suspended from the upper rail 6 by a respective roller 20 and the rollers run along channels 18 to enable the doors to slide relative to the upper rail 6.

A protective flange 22 depending from the upper rail 6 protects the roller assemblies. The rollers 20 are releasably secured to the doors 14,16 by means of bolts 24 in order to facilitate replacement of the doors if required. The panel member 10 is located in a channel 26 of the upper rail 6 and lies adjacent the fork-lift truck.

In order to facilitate servicing of the engines of some fork-lift trucks, it is necessary to raise an engine cover or the like. It is therefore preferable that the screen assembly does not interfere with such action.

Accordingly, the screen assembly 1 of the invention is preferably pivotally connected or hinged to the fork- lift truck, typically at the front or at the rear, to facilitate access for servicing.

Such an arrangement is shown in figure 4 where the screen assembly 1 is in the hinged open position to allow access to the engine cover 28. Two hinges 30 are provided on the panel member side of the screen assembly. The hinges 30 may be of the pin type which locate in corresponding sockets provided on the fork- lift truck so that the door can be readily lifted off if required.

A securing or lock mechanism may be provided at the opposite side to the hinges to allow the screen assembly to be secured in the closed position.

Referring to figure 5, the side door 14 carries an engagement means 32 which in use abuts against a portion of the central door 16. The engagement means comprises a projecting member which projects towards the central door 16 and is typically mounted on the frame 34 of the side door 14 so that as the side door 14 is moved, the projecting member 32 contacts the frame 36 of the central door 16.

Thus, when the side door 14 is moved to the closed position, the projecting member 32 engages the frame 36 of the central door, causing the central door to close and thereby fully closing the doorway. Similarly, when the side door 14 is moved to the open position, the projecting member 32 engages the frame 36 of the central door, causing the central door to open and thereby fully opening the doorway.

Fig. 5 (a) shows the side and central doors in the fully closed state and Fig. 5 (b) shows the doors in the partially open state.

The lower rail arrangement of the screen assembly is shown in figure 6. The lower rail comprises respective guides 38 for the doors 14,16. The guides 38 are releasably secured to the body of the fork-lift truck 2 by suitable bolt arrangements 40.

The screen assembly of the invention may be susceptible to damage by careless driving. In order to avoid this a protective bar 42, preferably of steel or the like, may be bolted, welded or otherwise secured to the fork-lift body, typically below the lower rail 8.

Typically, the protective bar 42 is of greater width than the width of the combination of door panels, that is the protective bar 42 extends further from the fork- lift body than the screen assembly 1, as shown in figure 6.

Typically, the screen assembly further comprises spaced apart side rails members 44 connecting the upper and lower rail members 6,8 to form an outer frame of the assembly.

It will be appreciated that the present invention is not intended to be restricted to the details of the above embodiment which is described by way of example only.