FIELD OF THE INVENTION

The present invention relates to a mobile or travelling stage and more particularly, relates to improvements in mobile stages and a method of erecting a mobile stage.

BACKGROUND OF THE INVENTION

A variety of stage structures are known in the art. These stages are intended to be temporary structures, usually for periods of time ranging from 1 day to several months. The stages may be used for many different purposes and typically are utilized for artistic performances of a limited duration.

Originally, temporary stages were erected manually and was a very labour intensive process, particularly if a stage of substantial size was needed. Frequently, the stages were without protection from the weather elements as the erection of a cover or roof was deemed to be too expensive.

More recently, so called mobile stages have been utilized for many artistic events. These mobile stages are mounted on a vehicle chassis and then various components of the stage are either erected or folded into position. Usually, these stages are of a limited size.

There remains a need for more elaborate stages for staging larger events.,

SUMMARY OF THE INVENTION

According to one aspect of the present invention, there is provided a mobile stage comprising a trailer having a base and wheels, a plurality of floor panels hingedly connected to each other, the panels forming a wall of the trailer, first and second floor support members pivotably connected to the base, the floor support members each having a plurality of legs secured thereto, four support masts designed to fit at corners of the panels, first and second primary trusses extending longitudinally of the trailer, a plurality of secondary trusses contained between the first and second primary trusses, and a roof membrane secured to the secondary trusses.

According to a further aspect of the present invention there is also provided a method of forming a stage comprising the steps of supplying a trailer having a longitudinally extending chassis and wheels, a plurality of panels hingedly connected to each other, the panels forming a wall about the trailer, first and second floor support members pivotably connected to the base, the first and second floor support members each having a plurality of legs secured thereto, first and second primary trusses extending longitudinally of the trailer, a plurality of secondary trusses contained between the first and second primary trusses, a roofing membrane secured to the secondary trusses, moving the first and second floor support members to extend perpendicularly to the longitudinally extending chassis, adjusting the plurality of legs secured to the floor support member to thereby level the floor support members, moving the plurality of panels to rest on the floor support members to thereby form a stage floor, erecting four support masts and securing the support masts to a respective corner of the stage floor, moving the primary trusses to extend perpendicular to the trailer floor, moving the secondary trusses between the primary trusses, and raising the primary and secondary trusses.

The mobile stage of the present invention is designed such that it can be erected with a minimal use of manpower compared to conventional arrangements. A substantial portion of the components of the mobile stage are hauled on a single truck or van, the van becoming a portion of the mobile stage. As used herein, the terms 'van' and 'trailer' are used interchangeably with it being understood that any suitable mobile structure may be utilized. Typically, the van is hauled by a tractor unit which then places the trailer in the desired position.

Initially, the trailer is levelled using jacks on the underside of the chassis of the trailer. Typically, hydraulic jacks would be utilized though any suitable type may be employed. The jacks will raise the chassis to the desired level and the wheels will be situated off the ground.

The first and second floor support members are pivotably connected to the chassis and they are moved outwardly to extend perpendicularly to the chassis. Each of the first and second floor support members will have a plurality of adjustable legs thereon. Initially, the further most leg would be adjusted to a level position with the remaining legs being adjusted to be in a ground contact position.

It is within the scope of the present to utilize an arrangement wherein the first and second floor support members are utilized to support a relatively small mobile stage. In most instances, a plurality of intermediate floor support members are deployed to provide support to the stage floor. Similarly, third and fourth floor support members may be utilized on an opposite side of the chassis to provide a larger stage. Again, intermediate floor support members would be employed.

Floor panels which are hingedly connected together form a side wall of the trailer. These floor panels may be unfolded to form the floor of the mobile stage. Again, a second set of floor panels may be provided on the opposite side of the chassis and deployed in a similar manner.

Four support masts are then placed in position at the four corners of the stage floor. These support masts may have been transported on the trailer or alternatively, a second trailer or other vehicle may be utilized. Typically, the support masts have a telescoping structure and may be placed in position by means of a crane or the like.

The support masts, as previously mentioned are connected to the stage floor and they also support the roof of the mobile stage. The roof structure will be formed from first and second primary trusses which are pivotably connected. Again, depending on the size of the stage floor, third and fourth primary trusses may also be utilized. The chassis of the vehicle functions as a major structural component of the stage and the support masts may be connected to the chassis by means of cables or other suitable connections.

A plurality of secondary trusses are mounted on the primary trusses and can move along the primary trusses by means of rollers as will be described in the illustrated embodiment. The secondary trusses are secured in place by any suitable means.

A roof is deployed and supported by the secondary trusses. The roof is preferably of a membrane type. The roof is preferably permanently secured to the secondary trusses and will unfold as the secondary trusses are placed in position. Naturally, if one desired, a separate roof membrane can be employed and secured in position though this will involve extra labour. Preferably, the roof fabric is one which has the capability of carrying in excess of 25 pounds per square foot and can be walked on by technicians during installation if required.

When the roof is deployed in position, it may be secured to the support mass. The system preferably includes winches located within each column and which winches may be utilized to lift the roof into position. Once the roof is in position, conventional cables and cross bracing may be utilized to fully stabilize the assembly. BRIEF DESCRIPTION OF THE DRAWINGS

Having thus generally described the invention, reference will be made to the accompanying drawings illustrating an embodiment thereof, in which:

Figure 1 is a perspective view of an erected mobile stage according to one

embodiment of the present invention;

Figure 2 is a side elevational view of a trailer for transporting the mobile stage;

Figure 3 is a side elevational view illustrating the levelling of the trailer;

Figure 4a is an end elevational view of the trailer carrying the trailer carrying the mobile stage;

Figure 4b is a cross-sectional view through the bed or chassis of the truck;

Figure 5 is a perspective view of the base of one of the support masts;

Figure 6 is a perspective view illustrating the commencement of the erection process;

Figure 7 illustrates the deployment of the floor support members;

Figure 8 is an end elevational view illustrating placement of the floor on the floor support members;

Figure 9 illustrates the assembly of the primary roof trusses;

Figure 10 is a side elevational view of the floor and roof trusses;

Figure 11 is a perspective view illustrating partial assembly of the secondary roof trusses;

Figure 12 is a side elevational view showing the bottom of the support masts;

Figure 13 and 14 illustrate the securement of the support masts to the floor;

Figure 15 is a top elevational view of the connection of the floor and support masts; Figure 16 is a side elevational view of the lifting of the roof structure; Figure 17 is an enlarged top view of the support masts; and

Figure 18 is a perspective view of a wind wall which may be utilized in the practice of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings in greater detail and by reference characters thereto, the mobile stage generally designated by reference numeral 10 is shown in an erected condition in Figure 1 and in the stored mobile position in Figure 2.

After being transported to the desired location, the van or trailer generally designated by reference 12 is detached from a tractor unit as shown in Figure 2. Subsequently, hydraulic jacks 18 are deployed to raise the chassis 16 off the ground. Foot pads or pedestals 22 and braces 20 are utilized as is conventional. Subsequently, a plurality of manually adjusted supporting legs 24 are deployed. Braces 26 may be utilized in

conjunction with supporting legs 24. Naturally, it will be understood that other

arrangements may be utilized including various combinations of hydraulic, electric, manual, pneumatic, etc. Naturally, a levelling process will be utilized.

Initially, and as shown in Figure 6, outer floor support members 28 are pivoted outwardly from the chassis 16 of van 12. As seen in the drawings, there may be four such outer floor support members 28; naturally, if a smaller stage were desired, only two such outer floor support members 28 on a single side of chassis 16 could be deployed. Each floor support member 28 has a plurality of legs 30 extending downwardly therefrom.

Preferably, all the legs are length adjustable.

A plurality of inner floor support members 32 are then connected by suitable means to outer floor support members 28. In a manner similar to outer floor support members 28, inner floor support members 32 each have a plurality of legs 34 which are preferably length adjustable.

With floor support members 28, 32 in position, a plurality of floor panels 36 connected by a hinge arrangement 38 are moved into position as shown in Figure 8. Floor panels 36 on the other side of van 12 would be similarly unfolded.

The roof structure is then opened up. In this respect, as shown in Figure 9, four primary trusses which are hingedly connected, are opened up to form to parallel primary trusses extending perpendicular to the length of chassis 16. As may be seen, each of primary trusses 50 is in the form of a ladder truss having perpendicular members 52 and diagonal members 54 extending between rails 56, three of which are shown.

After securement in the desired position, secondary trusses 58 are then moved into position. As shown in Figure 1 1 , each of the secondary trusses 58 has guide rollers 60 so that they are moveable along primary trusses 50 to their desired position where they may be secured in place by any suitable means.

A roof 62 of a membrane type is secured to secondary trusses 58 by means of roof retaining bars 64.

The invention utilizes four telescopic support masts 42, one of which is placed at each of the four corners. They are secured to floor panels 36 as will be discussed in greater detail hereinbelow. Each of the telescopic support masts 42 comprises four vertical members 44 interconnected by a plurality of horizontal members 46. At the lower end of each of telescopic masts 42, there are provided adjustable pads 48. As seen in Figure 5, preferably four such foot pads 48 are provided for each support mast 42. Braces 45 are used as required. A plurality of mast interface units 66 are provided having a first member 68 secured to floor panels 36. There are provided a pair of lock pins 70 and 72. A second member 74 is secured to support mast 42 and has a recess 76 and a pair of apertures 78, 79 each designed to receive one of lock pins 70, 72 while bar 81 fits within recess 76.

Mounted in the top of each telescopic member 42 is a winch 86. A motor 88 is mounted at the top of each support mast 42 and a cable 90 extends therefrom. Cable 90 engages with a hook 92 on primary truss 50 to lift the same to position.

The illustrated embodiment also provides for roof extension 94 which are moveable outwardly by means of a motor 96 although other means including manual means could be utilized. A rod 98 will engage through eye 100.

A mast holding from 104 is a U-shaped member designed to support mast 42 as seen in Figure 17.

Turning to Figure 18, it will be seen that there may be provided a wind wall 1 10 extending between support masts 42. A rail or track 106 will extend between support masts 42 on the floor panels 36. Wind wall 1 10 which is pleated, may move between open and closed positions. In this respect, the process may be automated whereby a wind speed device 1 12 will indicate what the wind load is or will be and act accordingly to put in place or retract wind wall 110. Suitable known drive means may be utilized in conjunction with release pin 1 14.

The movement of wind wall 110 may be either manual or automated. It can also be operated by remote control if so desired.