Patent Publication Number: US-7584575-B2

Title: Variable height fold and roll staging and method of assembling same

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to portable equipment for forming a staging platform. In particular, the present invention is directed to a portable platform assembly having a first platform panel pivotally connected to a second platform panel and with the second platform panel pivotally connected to a base assembly. When assembled as a staging platform, the first platform panel has at least one ground engaging support and also is supported by the second platform panel which is supported by its own ground engaging supports. All ground engaging supports may provide a single platform height or may be adjustable in length to attain various platform heights. The portable platform assembly is capable of use alone or together with similar assemblies to create a larger staging platform. In general, this type of staging equipment is referred to as fold and roll staging because it has a position for use, where it is substantially parallel to a ground surface, and may be folded to an upright position for storage, where the platform panels are substantially perpendicular to the ground surface and the assembly may be moved on a base having wheels. The present invention further includes a method of assembling the portable platform assembly for use as a staging platform. 
     2. Discussion of the Prior Art 
     Portable platform assemblies are widely used, such as for staging equipment in auditoriums, gymnasiums, and event halls to accommodate performers or spectators on an as-needed basis. Depending on the intended use, a facility may require such equipment to be moved between use and storage positions on a repeated basis. Despite the frequent need for staging in their activities, many organizations do not have access to facilities with permanent staging platforms. Because of the temporary nature of the staging used by some organizations, it is desirable to have staging that is, among other desirable properties, easy to set-up, stable during use, easy to transport, and easy to store. However, portable staging having two platform panels typically has the same type and number of ground engaging supports to support each of the platform panels when in use, with each of the panels also connected to a base having wheels. Unfortunately, it is common for these assemblies to be constructed in a way whereby when one attempts to lower a first platform panel onto its ground engaging supports, the second panel is toppled from its upright position, and unless restrained by personnel, will fall toward the ground. Thus, set-up of prior art fold and roll portable staging is not intuitive and may be awkward. 
     Manufacturers often incorporate wheels on such equipment, usually of the caster type, for use in moving the equipment from a storage location to a position for use as a platform. Sometimes each wheel has a break mechanism to park the equipment in one position for use. 
     In addition, portable staging often is made to have only a single platform height. Therefore, it also is desirable to have staging that may provide a single height, or that is adjustable to more than one height, thereby eliminating the need for having multiple units each capable of forming only a single stage height. 
     In view of the above, there remains a need for staging that is easy to transport and store, is simple and intuitive to assemble, and stable during storage, assembly and use. It also is desirable to have portable staging that has the added benefit of being adjustable to a variety of platform heights. Ease of set-up may reduce the number of personnel needed to assemble a platform and increase safety, while greater flexibility in height increases the number and variety of performances that can be executed using the same portable staging assemblies. 
     SUMMARY OF THE INVENTION 
     The purpose and advantages of the invention will be set forth in and apparent from the description and drawings that follow, as well as will be learned by practice of the invention. 
     The present invention is generally embodied in a portable staging assembly. In a first aspect, the invention provides a portable staging assembly having a first platform panel pivotally connected to a second platform panel. The second platform panel further is pivotally connected to a base assembly. When the first and second platform panels are in position for use substantially parallel to a ground surface, the second platform panel is supported by a plurality of ground engaging supports and the first platform panel is supported by at least one ground engaging support and by the second platform panel. In another aspect of the invention, all of the ground engaging supports are adjustable in length to provide variable height staging. 
     By placing the at least one ground engaging support for the first platform panel at a distance from the pivotal connection between the first and second platform panels, the first platform panel may be pivoted to a position at an acute angle or parallel to the ground surface without causing the base assembly or second platform panel to be lifted or otherwise moved relative to the ground surface. Thus, uncontrolled toppling of the second platform panel is avoided and a single person may safely and swiftly form a portable stage. In addition, fewer ground engaging supports may be used for the first platform panel than for the second platform panel because the first platform panel is supported in part by the second platform panel. 
     The invention also provides a new method of assembling a portable stage. The method includes rolling across a ground surface a portable staging assembly having first and second platform panels pivotally connected to each other with the platform panels in a storage position substantially perpendicular to the ground surface, and further having the second platform panel pivotally connected to a base assembly having wheels. While maintaining the second platform panel in the storage position, the first platform panel is pivoted from the storage position to a position at an acute angle or parallel to the ground surface wherein the first platform panel is supported by at least one ground engaging support connected to the first platform panel and by the second platform panel. The method further involves pivoting the second platform panel to a position substantially parallel to the ground surface to rest on a plurality of ground engaging supports connected to the second platform panel while simultaneously locating the first platform panel in a position substantially parallel to the ground surface. 
     In another aspect of the method provided, a first platform panel restraint may be disengaged to permit pivoting of the first platform panel from the storage position to the position at an acute angle or parallel to the ground surface. In yet a further aspect of the method, a second platform panel restraint is automatically disengaged when the first platform panel is pivoted to the position at an acute angle or parallel to the ground surface, so as to then permit the second platform panel to be moved to a position substantially parallel to the ground surface. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary, provided for purposes of explanation only, and are not restrictive of the invention as claimed. Further features and objects of the present invention will become more fully apparent in the following description of the preferred embodiment and from the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In describing the preferred embodiment, reference is made to the accompanying drawing figures wherein like parts have like reference numerals and wherein; 
         FIG. 1  is a perspective view of a preferred embodiment of a portable staging assembly having first and second platform panels in a storage position substantially perpendicular to a ground surface. 
         FIG. 2  is a perspective view of the preferred embodiment with a first platform panel pivoted to be supported by a pair of ground engaging supports and by the second platform panel. 
         FIG. 3  is a perspective view of the preferred embodiment in a position for use, with both the first and second platform panels positioned substantially parallel to the ground surface and supported by ground engaging supports. 
         FIG. 4  is a side view of the preferred embodiment in a position for use as in  FIG. 3  but having the ground engaging supports extended to provide a raised height staging platform. 
         FIGS. 5A-5E  are a series of side views showing the first and second platform panels of the preferred embodiment in successive positions between a storage position substantially perpendicular to the ground surface and a position for use wherein the first and second platform panels are substantially parallel to the ground surface. 
     
    
    
     It should be understood that the drawings are not to scale. While considerable mechanical details of the portable staging assembly, including details of fastening means and other plan and section views of the preferred embodiment depicting the invention have been omitted, such details are not per se part of the present invention and are considered well within the comprehension of those skilled in the art in light of the present disclosure. It also should be understood that the present invention is not limited to the preferred embodiment illustrated. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring generally to  FIGS. 1-4  and  5 A- 5 E, it will be appreciated that a portable platform assembly  10  of the present invention generally may be embodied in numerous configurations. The assembly  10  may stand alone, or may be grouped together with similar assemblies to form a larger platform or stage configuration. 
     The portable platform assembly  10  has a first platform panel  12  pivotally connected to a second platform panel  14  at pivot  16 . Second platform panel  14  also is pivotally connected to base  20  at pivot  22 . Base  20  has wheels  24  to permit assembly  10  to be easily transported when in a storage position with first and second platform panels  12 ,  14  in a position substantially perpendicular to the ground surface. Wheels  24  may be of the typical swivel caster type and for safety purposes, wheels  24  may be provided with locking mechanisms by which the swivel caster wheels  24  can be locked to prevent rolling. 
     First platform panel  12  generally includes an understructure or frame  30  to which is mounted a deck  32 . Also connected to first platform panel  12  are ground engaging supports  40 , shown as leg structures. Ground engaging supports  40  may be in a fixed position perpendicular to first platform panel  12 , or may be capable of being folded to a position parallel to first platform panel  12  for storage, and to a position perpendicular to platform panel  12  for use. 
     As best seen in  FIG. 4 , ground engaging supports  40  include a first tube  42  and may include a second tube  44  to form a telescopic leg. Second tube  44  further has a series of spaced apart holes  46  therethreough. Second tube  44  may be locked in various height positions by locking mechanism  48 . Locking mechanism  48  includes a pin  50  which extends through an outer first tube  42  as well as one of the series of holes  46  through second tube  44 . Within the scope of the invention, alternatively well known ground engaging supports or various structures for adjustable telescopic legs may be used. Also, to facilitate a more compact storage configuration, any one of a number of folding structures may be utilized for ground engaging supports  40 , such as the sliding gusset  52 , shown in  FIG. 1 , or the folding gusset  54  shown in  FIG. 4 . Moreover, first platform panel  12  may simply have a single wide ground engaging support spaced from the pivotal connection  16  to second platform panel  14 . 
     Second platform panel  14  has ground engaging supports  60 . The ground engaging supports  60  are rigidly fixed to second platform panel  14  and may include further lateral members  62  and longitudinal members  64  to fix ground engaging supports  60  in their relative positions spaced from each other. 
     Each ground engaging support  60  includes a first tube  66  and may include a second tube  68  to form a telescopic leg. Second tube  68  may include a series of spaced apart holes  70  (shown in  FIG. 4 ) to permit a plurality of platform height settings. The various height of each support may be selected and locked with a locking mechanism  72  that includes a pin  74  which extends through the first tube  66  and second tube  68 . Once again, alternative support structures, locking mechanisms or pin structures may be used. 
     Ground engaging supports  60  that are closest to pivotal connection  16  include members  80  which extend perpendicularly to ground engaging support  60  and terminate in pivotal connection  22  to base  20 . The positioning of member  80  along the ground engaging support  60 , relative to pivot  22 , helps adjust the center of gravity of the assembly, so as to establish a stable feeling of the platform panels  12 ,  14  when in the upright storage position. Also, the unique structure of the present invention permits both platform panels  12 ,  14  to be relatively close to the ground surface when in the upright storage position, further enhancing the stability of assembly  10 . 
     Second platform panel  14  generally includes an understructure or frame  82  to which is mounted a deck  84 . Mounted adjacent deck  84  and between the structural members of frame  82  is a storage rack  86  for storing the second tubes used in forming the telescopic legs, as shown in  FIG. 2 . 
     The pivotal connection  16  between first platform panel  12  and second platform  14  may be constructed in numerous ways. For instance, as shown, the hinge may be of a flexible material type, such as rubber or a woven fabric, with the material affixed to the edge at the inner end of each of the platform panels  12 ,  14 . Similarly, the pivotal connection  16  may be formed by a series of hinges or an elongated piano hinge affixed to each of the platform panels. 
     One of the advantages of the present invention is that first platform panel  12  may be supported by fewer ground engaging supports than second platform panel  14 . This is because first platform panel  12  is supported by at least one ground engaging support  40  along the outer end and by second platform panel  14  along the inner end. Eliminating the ground engaging supports adjacent the inner end of first platform panel  12 , allows first platform panel  12  to be lowered toward the ground surface to the position at an acute angle or parallel to the ground surface without the tendency to lift base  20  or topple the remaining upright second platform panel  14 . 
     If pivotal connection  16  is of sufficient strength, pivotal connection  16  may be sufficient to transfer loads from first platform panel  12  to second platform panel  14 , and ultimately down through ground engaging supports  60  of second platform panel  14 . However, as an added safety feature, or when pivotal connection  16  is not sufficiently strong to support such loads, a support arm  88  may be connected to second platform panel  14  to support the inner end of first platform panel  12  when platform panels  12 ,  14  are in a position for use, substantially parallel to the ground surface, as shown in FIGS.  4  and  5 C- 5 E. Support arm  88  also is employed as a stop to support second platform panel  14  from pivoting toward first platform panel  12  when platform panels  12 ,  14  are in the upright storage position. In this manner, second platform panel  14  may not pivot past its upright position, substantially perpendicular to the ground surface. 
     For added safety, a first restraint  90 , best seen in  FIG. 1 , is used to lock first platform panel  12  to second platform panel  14  when both platform panels are in the storage position, substantially perpendicular to the ground surface. First restraint  90  may be of any type which can temporarily hold the two platform panels close together at their outer ends when in the storage position. As shown in  FIG. 1 , a second restraint  92  may be employed to prevent platform panels  12 ,  14  from pivoting toward a use position of second platform panel  14  when platform panels  12 ,  14  are both still in a storage position. In this embodiment, second restraint  92  is connected to first platform panel  12  and engages base  20  via a catch  94  mounted to base  20 . As shown in  FIG. 2 , once first platform panel  12  has been pivoted toward the ground surface, restraint  92  releases from catch  94  to permit second platform panel  14  to be pivoted toward the use position, parallel to the ground surface. 
     Now turning to the method of assembling the portable platform assembly  10  of the present invention (best seen in  FIGS. 5A-5E ), it will be appreciated that when platform panels  12 ,  14  are in the upright storage position, assembly  10  may be rolled across a ground surface on wheels  24  of base  20 . In this manner, assembly  10  may be moved into a desired position for use, as shown in  FIG. 5A . To place the assembly in position for use, if so equipped, at least one of swivel caster wheels  24  may be locked to prevent further rolling. 
     If ground engaging supports  40  on first platform panel  12  are of the folding type, then ground engaging supports  40  are moved to their position for use, perpendicular to first platform panel  12 , as shown in  FIGS. 1 and 5B . If the assembly  10  is equipped with telescopic legs, then second tubes  44  may be inserted in first tubes  42  of ground engaging supports  40  of first platform panel  12 . In a similar manner, second tubes  68  may be inserted in first tubes  66  of ground engaging supports  60  of second platform panel  14 . Once the appropriate height for each leg is selected and the leg tube lengths are locked in place, such as by respective pins  50 ,  74 , then first restraint  90  may be unlocked to permit first platform panel  12  to pivot toward a position more parallel to the ground surface. 
     Second platform panel  14  remains in the upright position while first platform panel  12  is pivoted to a position at an acute angle or parallel to the ground surface, where it is supported by at least one ground engaging support  40  at the outer end and by second platform panel  14  at the inner end, as shown in  FIGS. 2 and 5C . The pivoting of first platform panel  12  releases second restraint  92  from catch  94  to permit second platform panel  14  to be pivoted toward the ground surface. As second platform panel  14  is pivoted toward the use position on the ground surface, ground engaging supports  60  along the inner end of second platform panel  14  will engage the ground surface first, and pivotal connection  16  at the inner ends of platform panels  12 ,  14  is raised, as shown in  FIG. 5D . Then, as the ground engaging supports  60  along the outer end of second platform panel  14  contact the ground, pivotal connection  16  at the inner end of platform panels  12 ,  14  is raised until first and second platform panels  12 ,  14  are in a common plane, substantially parallel to the ground surface, as shown in  FIGS. 3 ,  4  and  5 E. Depending on the chosen length of the ground engaging supports  40 ,  60 , the pivoting of second platform panel  14  to a use position may leave wheels  24  of base  20  relatively adjacent the ground surface, such as shown in  FIG. 5E , or may lift base  20  more substantially above the ground surface, such as shown in  FIG. 4 . Once in position for use, platform assembly  10  is effectively parked on ground engaging supports  40 ,  60 . 
     To move platform assembly  10  to a storage position, the process of assembling platform assembly  10  is reversed. Thus, briefly, platform assembly  14  is pivoted to the upright position, until support arms  88  contact base  20  and platform panel  14  achieves a position substantially perpendicular to the ground surface. This, in turn, brings wheels  24  of base  20  into substantial load-bearing contact with the ground surface. Next, platform panel  12  is pivoted to the upright position. This reengages second restraint  92  on first platform panel  12  with catch  94  on base  20 . First restraint  90  is then reengaged to lock first platform panel  12  to second platform panel  14 . If desired, respective second tubes  44 ,  68  of the telescopic leg assemblies may be removed and stored, such as in rack  86 . If foldable, ground engaging supports  40  of first platform panel  12  may be folded to a storage position, substantially parallel to platform panel  12 . Platform assembly  10  is now ready to be rolled to a position for storage. 
     It will be appreciated that platform assembly  10  of the present invention may be constructed in various configurations. A variety of materials and shapes of components may be used, and may be joined to each other in any number of conventional manners, such as by welding or with suitable fasteners. 
     Finally, it should be understood that while a preferred embodiment has been described herein, any variety of fastening means, suitable materials of construction, and dimensions may be used to satisfy the particular needs and requirements of the end user. It will be apparent to those skilled in the art that various modifications and variations can be made in the design and construction of a platform assembly without departing from the scope or spirit of the present invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed therein.