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RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/416,954 entitled “Lightweight Portable Stage”, filed Oct. 7, 2002, hereby fully incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention is directed to a portable stage, and more particularly to a lightweight mobile trailer based stage that is towable with a light vehicle and that can be deployed and used by one individual.  
         DESCRIPTION OF THE RELATED ART  
         [0003]    Outdoor speeches, concerts, and other public performances are commonplace in everyday life. Often, these performances are by an individual performer, or a small group of performers, before a small audience. It is usually advantageous for the performer to be positioned higher than the audience on a platform or stage for better visibility and sound quality.  
           [0004]    Numerous examples of portable stage assemblies have been previously disclosed in the art. One example of a previous portable stage assembly is disclosed in U.S. Pat. No. 6,006,680 to Quam. The portable stage platform disclosed therein has a performance platform with a plurality of collapsible legs coupled to the underside of the platform. This device may be relatively difficult to use on uneven ground such as may be encountered at some outdoor venues, however, because it rolls on casters and does not have provisions for towing by a motor vehicle.  
           [0005]    In U.S. Pat. No. 5,848,501, a modular portable stage system is disclosed. U.S. Pat. No. 5,848,501 is commonly owned by the owners of the present invention and is hereby fully incorporated herein by reference. This portable stage system includes a number of standardized modular components that can be used to construct a platform that is easily adaptable to a wide variety of designs. The components, although collapsible or capable of disassembly, must be individually set-up and are not packaged so as to be easily deployable by an individual.  
           [0006]    Some prior devices have been built on a trailer, towable by a motor vehicle. One example of such a prior device is disclosed in U.S. Pat. No. 3,620,564 to Wenger, et. al., which patent is commonly owned by the owner of the present invention and hereby fully incorporated herein by reference. Other examples are disclosed in U.S. Pat. No. 5,078,442 to Rau, et. al., reissued as U.S. Reissue Pat. No. RE34,468, U.S. Pat. No. 5,152,109 to Boers, U.S. Pat. No. 5,546,709 to Decker et. al., U.S. Pat. No. 6,176,495 to Decker, each commonly owned by the owner of the present invention and likewise fully incorporated herein by reference. Yet another example is the portable stage disclosed in U.S. Pat. No. 6,393,769 to Mertik, et. al. These are generally large and heavy devices, however, and typically require relatively heavy vehicles for towing and transport. Also, their large size and weight makes deployment by an individual difficult.  
           [0007]    Previous smaller scale trailer based mobile stages have likewise not been entirely satisfactory. Even with a small stage, it is typically desirable to carry accessory items for use with the stage, such as railings, access stairs, skirting and the like. Musical performances may require bulky or heavy items such as large audio amplifiers and lights. Exhibits, such as for art fairs and festivals, may involve significant amounts of merchandise and bulky display structures. Previous small mobile stages typically have had no, or very limited, ability to carry these items, requiring them to be transported in the tow vehicle or separately.  
           [0008]    What is still needed is a small-scale self-contained mobile stage system for outdoor performances transportable with a light tow vehicle, with features for easy deployment by one person alone.  
         SUMMARY OF THE INVENTION  
         [0009]    The present invention substantially meets the needs of the industry by providing a small-scale self-contained mobile stage system for outdoor performances transportable with a light tow vehicle, with features for easy deployment by one person alone. In the invention, a mobile stage trailer adapted for towing by a light tow vehicle includes a chassis having a pair of decks including an upper deck and a lower deck vertically spaced apart from the upper deck. A hitch assembly is operably coupled with the chassis for selectively coupling the trailer with the tow vehicle. A wing deck is operably coupled with the chassis at each lateral edge of the chassis. The wing decks are selectively positionable in a first favored position proximate the upper deck of the chassis portion so that the upper deck and the wing decks together present an upwardly directed surface for performances. The wing decks are further selectively positionable in a second favored position for towing wherein the system presents a system width dimension generally equal to the width of the chassis alone.  
           [0010]    The portable stage of the present invention may be capable of deployment in outdoor locations having uneven or soft ground. The apparatus includes a lightweight chassis having a structural frame and deck with high load-bearing capacity and low deflection. The stage has a deck for transporting cargo and another deck that forms a portion of the performance surface of the stage. The stage may have one or more fold-out wing decks that may be alternately configured in an position for towing, and in a performance position substantially co-planar with the upper deck of the chassis. The fold-out wing deck portions may also be optimized for light weight, high strength and low deflection. In the performance position, the wing portions enlarge the performance surface of the stage. The lower deck provides cargo space to securely store and transport accessories and other items that may be needed for a performance.  
           [0011]    The portable stage of the present invention is easily deployed and used by an individual. The stage is lightweight, making it easily maneuverable by an individual by hand, and may be towed with a light duty vehicle such as an automobile or light truck. Lift assist means are provided to assist an individual in raising and lowering the wing portions. All supports and jacks for leveling and stabilization of the stage apparatus may be operable by an individual without assistance from others.  
           [0012]    The stage may be used with other portable stage assemblies to form larger performance surfaces and may also be used with modular portable stage components. The hitch assembly is removable or retractable to facilitate attachment of the stage to other portable stages or components. In addition, a variety of accessories, such as a lightweight overhead weather covering, access stairs, and guardrails may be used with the stage.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a side elevation view of the lightweight portable stage of the present invention with the stage configured for towing;  
         [0014]    [0014]FIG. 2 is a perspective view of the stage configured for towing;  
         [0015]    [0015]FIG. 3 is a perspective view depicting a selectively positionable stage leveling jack positioned in a stage transport position;  
         [0016]    [0016]FIG. 4 is a perspective view of the stage leveling jack of FIG. 3, with the jack positioned for leveling the stage;  
         [0017]    [0017]FIG. 5 is a perspective view of a front portion of the portable stage depicting a retractable hitch assembly in the extended position;  
         [0018]    [0018]FIG. 6 is a perspective view of the retractable hitch assembly of FIG. 5, depicting the hitch in a disassembled and retracted condition;  
         [0019]    [0019]FIG. 7 is a top cutaway plan view of the retractable hitch assembly in the extended position;  
         [0020]    [0020]FIG. 8 is a top cutaway plan view of the retractable hitch assembly in the retracted position;  
         [0021]    [0021]FIG. 9 is a rear elevation view of the stage depicting deployment of the wings from a folded-up towing or transport position to a folded-down performance position;  
         [0022]    [0022]FIG. 10 is a side elevation view of an adjustable length leg assembly according to the invention;  
         [0023]    [0023]FIG. 11 is a cut-away cross section view of a portion of the adjustable length leg assembly depicted in FIG. 10;  
         [0024]    [0024]FIG. 12 is a perspective view of a cargo tie-down track and tie-down ring assembly;  
         [0025]    [0025]FIG. 13 is a perspective view of tie down track cover strips fitted into the cargo track of FIG. 12;  
         [0026]    [0026]FIG. 14 is a perspective view of the chassis portion with the wings in the folded-out position;  
         [0027]    [0027]FIG. 15 is an view of a corner portion of the stage;  
         [0028]    [0028]FIG. 16 is a side elevation view of the clamp portion of a detachable railing in an initial stage of installation on an edge of the stage;  
         [0029]    [0029]FIG. 17 is a side elevation view of the clamp portion of the detachable railing in intermediate and final stages of installation on an edge of the stage;  
         [0030]    [0030]FIG. 18 is a partial perspective view of the portable stage assembly and accessories in a fully deployed configuration; and  
         [0031]    [0031]FIG. 19 is a view of the stage with a weather protective canopy installed thereover. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0032]    Portable stage  20  according to the present invention generally includes main portion  22 , and a pair of wing portions  24 ,  26  connected to main portion  22  with hinges  28 . Main portion  22  generally includes chassis  30  and wheel assembly  32 . Chassis  30  generally includes upper frame  34  and lower frame  36 , which are spaced apart and secured together by uprights  38 . Upper frame  34  and lower frame  36  may be constructed from hollow metal shape stock, preferably rectangular tube stock. Each frame  34 ,  36 , has a pair of side rails  40 , which are spaced apart at opposite sides of the frame  34 ,  36 . Lateral support members  42  span between the pair of side rails  40 . Purlins  44  stabilize and provide bracing for lateral support members  42 . Upper frame  34  supports upper deck  46 , which presents a portion of performance surface  48 . Lower frame  36  supports lower deck  50 , which presents cargo surface  52 . Cargo area  54  is defined between upper deck  46  and lower deck  50 . It is most preferred that upper deck  46  be positioned at about 36 inches above ground level when stage  20  is deployed.  
         [0033]    Cargo surface  52  may be fitted with suitable tie-down points  56  for securing items of cargo. For example, as depicted best in FIG. 12, one or more slotted tie down strips  58 , commonly known as “airliner tracks” may be fastened to cargo surface  52 . One or more ring assemblies  60 , which are adapted to cooperate with tie down strips  58 , may be inserted as depicted in FIG. 12. Tie down straps  61  may then be looped through the ring assemblies  60  and around the cargo to be secured, which may be accessories such as railing section  214 . A layer  62  of a high-friction material such as rubberized polymer may be provided on all or selected portions of cargo surface  52  to frictionally contact and inhibit sliding of items placed on cargo surface  52 .  
         [0034]    Removable or hinged enclosure panels  64 , as depicted in FIG. 2, may be provided to partially or completely enclose cargo area  54 . Panels  64  may be provided with a latch handle  66  to enable securing of the panels  64  in place. Additionally, panels  64  may be equipped with a lock  68  integral with latch handle  66  as depicted, or as a separate assembly.  
         [0035]    Each wing portion  24 ,  26 , has a wing frame  70  constructed from a pair of longitudinal members  72  and a number of spanning lateral members  74 . Purlins  76  are again provided for stabilization and support of the lateral members  74 . Each wing portion  24 ,  26 , has a deck  78 , that forms a portion of performance surface  48 .  
         [0036]    The lightweight character of portable stage  20  is obtained, in part, by the selection of materials for chassis  30  and wing portions  24 ,  26 . It is preferred that rectangular or square aluminum tubing be used for upper frame  34 , lower frame  36 , and the wing frames  70 . Although the various component members can be fastened together in any suitable manner, all-welded construction is preferred for cost, strength, durability and weight purposes. The preferred sizes of each member may be selected using standard structural engineering methods. The structural components of the stage are preferably designed so that the performance surface has a design load bearing capacity of at least about 150 pounds per square foot with a design deflection of no greater than L/240.  
         [0037]    Also in keeping with the lightweight character and relatively low cost of the device, it is preferred that upper deck  46 , lower deck  50 , and wing decks  78  be formed from aluminum sheet material of suitable thickness so as to have appropriate load and deflection characteristics. Other metal, polymer or composite sheet materials having the appropriate strength and weight properties may also be used for decks  46 ,  50 ,  78 . A layer  80  of a high-friction material such as rubberized polymer may be provided on all or selected portions of performance surface  48  to frictionally contact and inhibit sliding of items on performance surface  52  and to prevent slips and falls. Again, one or more slotted tie down strips  58 , such as airliner tracks may be fastened to performance surface  48  to facilitate securing cargo for transport. Removable covers  58   a  may be provided as depicted in FIG. 13 to cover tie down strips  58  when stage  20  is used for performances, so as to alleviate any tripping hazard.  
         [0038]    The hinged connection of wing portions  24 ,  26 , with main portion  22  enables the wings to be folded in an upright towing position as depicted best in FIG. 2, or deployed in a performance position as depicted in FIG. 14. Hinge  28  may be a continuous hinge fastened to the outer lateral surface of upper frame  34  and the inner lateral surface of each wing portion  24 ,  26 . Alternatively, any other arrangement that enables hinging motion of wing portions  24 ,  26 , with respect to main portion  22 , including a number of smaller, separate hinges or one or more strips of flexible, resilient material, may be used.  
         [0039]    Chassis  30  presents a maximum width dimension, annotated W1 in the Figures. To optimize the available width of performance surface  48  while enabling legal towing of stage  20  over public roads, it is generally preferred that chassis  30  present a maximum width dimension W1 close to the maximum legal width dimension for trailers in the locations where stage  20  will be used. Consequently, it is also generally preferred that the overall width W2 of stage  20 , when wing portions  24 ,  26 , are positioned in the towing position, be no greater than the width W1 of chassis  30 .  
         [0040]    The folding motion of wing portions  24 ,  26 , may be assisted by a lifting device  86 , such as gas cylinder  88 . Gas cylinder  88  is pivotally attached to an upper cylinder mount  90  on wing frame  70 , and pivotally attached to a lower cylinder mount  92  on chassis  30 . Gas cylinders  88  bias wing portions  24 ,  26 , toward the towing position depicted best in FIG. 9. The biasing force supplied by gas cylinders  88  works to assist a user in raising and lowering the wing portions  24 ,  26 . For best results, it is currently preferred that gas cylinders  88  be selected, based on the weight and size of the wing portion, so that a force of no more than 100 pounds applied to the outer edge of the wing portion is necessary for either raising or lowering the wing. To resist movement of wings  24 ,  26 , from wind or shock forces during transport, removable wing braces  94  may be installed to brace and support the wings in the towing position as depicted in FIGS.  5  and  13 . Wing braces  94  may be held in place with threaded fasteners or with any other suitable means.  
         [0041]    Each wing portion  24 ,  26 , when deployed as depicted in FIG. 3, is supported by hinge  28  at inner edge  96  and by folding wing support legs  98  at outer edge  100 . Each wing support leg  98 , depicted best in FIGS. 10 and 11, generally includes a hollow upper leg  102  and a hollow lower leg  104 . The inner cross-section of upper leg  102  is dimensioned so as to slidingly receive lower leg  104  axially within. At the bottom end  106  of lower leg  104  is foot assembly  108 , which generally includes an attachment portion  110  in the form of a web  112  and a ground-engaging plate  114 . Foot assembly  108  is pivotally attached to lower leg  104  at pivot  115 , enabling foot assembly  108  to be folded so that the plane formed by ground-engaging plate  114  parallels the longitudinal axis presented by lower leg  104 , designated a-a in the Figures. In a preferred embodiment ground-engaging plate  114  has an area of at least about 35 square inches to enable appropriate load spreading and prevent the leg from sinking into soft ground. At the top end  116  of upper leg  102  is upper leg bracket  118 , which is attached to wing frame  70 . Upper leg bracket  118  is pivotally attached to upper leg  102  at pivot  120 , so that wing support leg  98  may be folded substantially parallel with the wing frame  70 . Latches, clips or other fastening devices, such as straps  119 , may be provided to secure the wing support legs  98  against wing frame  70  when the stage  20  is in transport.  
         [0042]    The length of each wing support leg  98  may be adjustable. Lower leg  104  has a series of regularly-spaced apertures  122  formed therethrough. It is preferred that apertures  122  be formed approximately ¼″ apart so as to enable a sufficiently fine degree of adjustment. Upper leg  102  has a single corresponding aperture  124 . Apertures  122  and aperture  124  are dimensioned so as to receive a pin  126 , and enable its insertion therethrough. Pin  126  has a handle  130 . In use, lower leg  104  may be slid in and out of upper leg portion  102  until the desired length is reached. The nearest aperture  122  may then be aligned with aperture  124 , and pin  126  may be inserted though the apertures  124 ,  126 , so that distal end  128  of pin  126  projects through the opposite side of wing support leg  98  from which it was inserted. When it is desired to readjust the length of the wing support leg  98 , pin  126  may be withdrawn by pulling handle  130  away from leg  98 . The length of each wing support leg  98  may thereby be adjusted to accommodate ground of varying elevation, while still maintaining the wing portion  24 ,  26 , in a stable, level condition.  
         [0043]    It is currently anticipated that the entire lightweight portable stage apparatus will preferably have an empty weight of from about 1,800 pounds to about 3,200 pounds, dependent on the number of axles and the area of the performance surface provided. The gross vehicle weight for the stage, fully loaded with cargo, is anticipated to preferably be from about 3,000 pounds to about 7,000 pounds. It is anticipated that the size of the performance surface  48  may range up to about 400 square feet in area. Stage  20  is capable of being towed by a light tow vehicle, generally including half-ton or even quarter-ton pickup trucks and vans.  
         [0044]    Main portion  22  may be stabilized in place and leveled using jacks  132  disposed at each of the four corners  134  of main portion  22 , as is best depicted in FIGS.  2 - 4  and  14 . Jacks  132  may be any type of jack as are well-known in the art and commonly used for trailer leveling applications. Each jack  132  includes an upper body portion  136 , and a lower body portion  138  axially movable within upper body portion  136 . Crank handle  140  is attached at the upper end of upper body portion  136 . Rotary cranking motion applied to crank handle  140  causes lower body portion  138  to move longitudinally in and out of upper body portion  136 , depending on the direction of rotary motion. Ground engaging plate  142  is attached to lower body portion  138 . Moreover, upper body portion  136  is attached to stage main portion  22  with mounting bracket  146 . Pivot  148  is provided to enable the entire jack  132  to be pivoted up to ninety degrees in the direction of the arrow, as depicted in FIGS. 2 and 4. Jack  132  may be secured to pivot  148  with a removable pin  150 . Leveling indicators  152 , which may be common spirit type levels, are provided at each corner  134  of chassis  30 , so as to provide a reference enabling a user to easily level the stage using jacks  132 .  
         [0045]    Stage  20  has features enabling it to be towed over public roads by a light duty vehicle, such as an automobile or light truck. An axle assembly  154  is provided, and generally includes a pair of wheel assemblies  156  disposed at each end of an axle  158 . Each wheel assembly  156  includes a pneumatic tire  160  mounted on a wheel  162 . Tire  160  may be any suitably sized standard tire manufactured for use with a utility trailer, automobile, or light truck. Similarly, wheel  162  may be any automotive type wheel of suitable size and that is compatible with tire  160 , such as for example, a standard steel or aluminum automobile wheel with a 4, 5, or 6 bolt pattern. A fender  164  is provided over each wheel assembly  156  to deflect road spray and rocks that may be thrown by the tires.  
         [0046]    Each wheel assembly  156  is bolted or otherwise attached to a hub  166 . The hubs  166  are fastened to opposite ends of axle assembly  158 . Axle  158 , which may be any axle assembly of a type commonly used for trailers, is secured with U-bolts  168  to a pair of leaf springs  170 . Leaf springs  170  are, in turn, attached to the underside of chassis  30 , and provide a spring suspension for absorbing road shock and vibration during towing. Although not depicted, shock absorbers may also be added to provide dampening for the springs and a smoother ride quality. Of course, it will be appreciated that any other suitable known suspension arrangement may be used. For example, coil springs, coil-over shock absorbers, struts, torsion bars, or any other resilient suspension element may be used in place of leaf springs  170 . Axle assembly  158  may also be rigidly mounted to chassis  30 , although ride quality would be severely degraded. Moreover, axle assembly  158  may be replaced, for example, by a differential assembly, or hubs  166  may be independently suspended. Electric or hydraulic brakes may be provided in hubs  166  to provide suitable stopping ability for the device. A second, tandem, axle assembly  172  may also be provided to increase the load capacity of the device, as depicted in FIG. 1.  
         [0047]    At the front of chassis  30 , hitch assembly  174  is provided as a means of attaching the stage  20  to a tow vehicle  208  for purposes of towing. Hitch assembly  174  generally includes a tongue  178  and a ball receiver  180 . As depicted in FIG. 3, ball receiver  180  is a standard component as is commonly used with utility trailers, and is adapted to fit over a ball  182  attached to the towing vehicle. Although any suitably sized ball may be used, it is currently anticipated that a 2{fraction (5/16)}″ inch ball will provide the best results. Latch  184  secures ball receiver  180  over ball  182 . A hitch jack  185  may be provided on tongue  178  to elevate and support hitch assembly  174  during hitching and unhitching operations. Hitch jack  185  has a ground engaging wheel  186 , which has a suitable ground contact patch so as to spread the tongue weight and prevent the jack from sinking into soft ground. The hitch jack  185  operates in a similar fashion to screw jacks  132  as previously described, and is raised and lowered by rotary motion imparted to crank  188 . Hitch jack  185  may be detachable to enable hitch assembly  174  to be retractable as depicted in FIGS.  5 - 8 .  
         [0048]    Hitch assembly  174  may be retractable to a position underneath chassis  30 , as depicted best in FIGS.  5 - 8 , so as to enable the attachment of additional platform sections as will be further described herein below, and to facilitate access around the perimeter of stage  20 . In this embodiment, hitch housing  190  is attached to chassis  30  below lower deck  50 . Hitch housing  190  has sides  192 , bottom panel  194 , and an open front  196 . Hitch assembly  174  is received in hitch housing  190 , extending through open front  196 , and is slidable fore-and aft as depicted in FIG. 7. Hitch assembly  174  is selectively positionable in a first extended towing position wherein hitch assembly  174  extends forwardly from chassis  30  as depicted in FIG. 7, and a second retracted or stowed position wherein all or a substantial portion of hitch assembly  174  is within housing  190  beneath lower deck  50  as depicted in FIG. 8. Pins  198  extend through apertures  200  in housing  190  on each side  192 , engaging corresponding apertures (not depicted) in hitch assembly  174  to secure it in place when hitch assembly  174  is positioned in the extended position as depicted in FIG. 7. Cutout  202  may be provided to facilitate access to hitch assembly  174  for positioning.  
         [0049]    Hitch assembly  174  may also include a suitable electrical connection cable  204  for connection with a vehicle electrical system to provide power and signals for running lights  205  and the brakes. Safety chains may also be included.  
         [0050]    It will be appreciated that a variety of alternatives to the described ball hitch arrangement exist for attaching the lightweight portable stage to a vehicle. For example, a pintle hitch or gooseneck arrangement could be used, with a suitably equipped towing vehicle.  
         [0051]    The operation and use of stage  20  may now be understood with reference to FIGS.  1 - 19 . With the stage  20  configured for towing as depicted in FIGS. 1 and 2, an individual user may hitch the stage  20  to a suitably equipped vehicle  208  by elevating hitch jack  185  to a sufficient height so as to clear the vehicle ball  182 , positioning the vehicle  208  so that the ball  182  is under ball receiver  180 , lowering hitch jack  185  so that ball receiver  180  engages ball  182 , and closing latch  184  to secure ball  182  in place. Stage  20  may then be towed to a desired location using vehicle  208 . Once in location, stage  20  may be unhitched from vehicle  208  by the user using the reverse of the procedure described above. Jacks  132  are lowered so as to engage the ground surface, and the stage is leveled using jacks  132  and with reference to leveling indicators  152 . Once main portion  22  is leveled, wing portions  24 ,  26 , may then be unlatched and lowered into a position generally coplanar with upper deck  46  of main portion  22 , forming performance surface  48 . Wing portions  24 ,  26 , are lowered by grasping outer edge  210  and pulling downward. Gas cylinders  88  provide a resisting force so as to support a portion of the weight of wing portions  24 ,  26 , and enable an individual user to easily support wing  24 ,  26 , as it lowers. Once each wing portion  24 ,  26 , is lowered, wing support legs  98  may be pivoted downward and adjusted for length so that plate  114  of each leg engages the ground and the wing portion is substantially level with upper deck  46 .  
         [0052]    Suitable accessories, for example steps  210 , and railings  212  may be attached to stage  20  as desired. Each section  214  of railing  212  generally includes a pair of uprights  216  connected by a top rail  218 , a mid-rail  220 , and a lower rail  221 . Each upright  216  has a c-clamp assembly  222  for attaching to stage  20 . C-clamp assembly  222  generally includes upper jaw  224 , which may welded directly to upright  216 , and a lower jaw portion  226  which slides over lower end  228  of upright  216 . Lower jaw portion  226  has notch  230 , which is dimensioned to receive structural member  232  at an edge of stage  20 , which may be part of upper frame  34  of chassis  30  or of wing frame  70 . Lower jaw portion  226  also includes threaded t-handle lever  234 , which is slidable in elongate slot  236 . Once upper jaw  224  and lower jaw portion  226  are engaged around an edge of stage  20 , threaded t-handle lever  234  may be slid under lower jaw portion  226  and tightened to clamp structural member  232  tightly between upper jaw  224  and lower jaw portion  226 , thereby securing railing section  214  on the edge of stage  20 . Accessories, including steps  210  and railing sections  214  may stowed in cargo area  54  or on upper deck  46  and secured with tie down straps to prepare stage  20  for transport.  
         [0053]    As an alternative to railing  212  described above, a railing as is described in U.S. Pat. No. 5,263,550 may be used. U.S. Pat. No. 5,263,550 is commonly owned by the assignee of the present invention, and is hereby fully incorporated herein by reference.  
         [0054]    In addition, a weather protective canopy may be deployed to cover the performance surface  48  as depicted in FIG. 19. As depicted, fabric canopy  242  is supported and secured in tent-like fashion over a lightweight space frame  244 . It is currently preferred that fabric canopy be fashioned from canvas, but other suitable materials such as rip-stop nylon may also be used.  
         [0055]    A fabric towing cover  246  may be provided to cover and protect stage  20  from moisture and road debris when stage  20  is configured for towing. Cover  246  may be secured to chassis  30  with straps  248 .  
         [0056]    Moreover, the available area of performance surface may be increased by positioning one of more stages  20  in proximity to each other, or by using modular stage components such as are disclosed and depicted in U.S. Pat. Nos. 5,848,501 and 6,106,186, both of which are commonly owned by the assignee of the present invention, and both of which are hereby fully incorporated by reference herein. As will be appreciated, the attachment apparatus and methods disclosed therein may be applied to attach multiple lightweight portable stages  20  together, and to attach modular components to the stages.  
         [0057]    As will also be appreciated, a variety of alternative configurations of the lightweight portable stage are possible. Although the embodiments depicted herein include a main portion  22  with a pair of laterally disposed wing portions,  24 ,  26 , embodiments having no wing portions, one wing portion, or any other number of wing portions are also possible. As an alternative, wing portions could also be configured so as to fold outward from the fore and/or aft ends of the chassis if desired.  
         [0058]    The present invention has been described with respect to particular illustrative embodiments. It is to be understood that the invention is not limited to the above-described embodiments and modifications thereto, and that various changes and modifications may be made by those of ordinary skill in the art without departing from the spirit and scope of the appended claims.

Summary:
A self-contained mobile stage system for outdoor performances that is transportable with a light tow vehicle, and with features for easy deployment by one person alone. The mobile stage trailer includes a chassis having a pair of decks, including an upper deck and a lower deck vertically spaced apart from the upper deck. A retractable hitch assembly is coupled with the chassis for coupling the trailer with the tow vehicle. A wing deck is coupled with the chassis at each lateral edge. The wing decks are selectively positionable in a first favored position proximate the upper deck of the chassis portion so that the upper deck and the wing decks together present an upwardly directed surface for performances. The wing decks are further selectively positionable in a second favored position for towing wherein the system presents a system width dimension generally equal to the width of the chassis alone.