US3021575A

US3021575A - Foldable stage

Info

Publication number: US3021575A
Application number: US753318A
Authority: US
Inventors: Heisler Harold
Original assignee: MIDWEST FOLDING PRODUCTS Mfg C
Current assignee: MIDWEST FOLDING PRODUCTS Mfg CORP; MIDWEST FOLDING PRODUCTS Mfg C
Priority date: 1958-08-05
Filing date: 1958-08-05
Publication date: 1962-02-20
Anticipated expiration: 1979-02-20

Description

Feb. 20, 1962 H. HEISLER 3,021,575

FOLDABLE STAGE Filed Aug. 5, 1958 2 Sheets-Sheet l /IO 2 /Q 12 INVENTOR. HAROLD HEISLER JOHN w GRAHAM ATTORNEY Feb. 20, 1962 H. HEISLER 3,021,575

FOLDABLE STAGE Filed Aug. 5, 1958 2 Sheets-Sheet 2 INVENTOR. HAROL D HEISLER JOH N W. GRAHAM AT TO RN EY United States, Patent Ofifice 3,021,575 Patented Feb. 20, 1962 This invention relates to a platform structure, and more particularly to a foldable stage which affords portability thereof.

This application constitutes a continuation-in-part of my copending patent application, Serial No. 568,386, filed February 28, 1956, now Patent No. 2,860,383.

In this prior application, a foldable platform or stage is disclosed which comprises a plurality of platform sections hingedly secured together along the respectively adjacent edges thefEDf for movement between an extended position wherein such sections define a generally horizontal plane, and a folded position defining a plurality of vertically disposed planes oriented in facing, parallel relation. To afford movement between these positions, the platform sections are supported centrally by a frame. Four elongated side rails or supports are pivotally secured to the frame, and in one position thereof support the horizontally disposed platform sections; and when the platform sections are folded, the elongated supports may be folded inwardly along the platform sections so as to compact the platform assembly.

Since the stage is intended to support a considerable weight thereon, it is desirable to effect an interconnection of the horizontal platform sections and elongated supports to rigidity the unit. A latching mechanism capable of achieving this result is disclosed in the prior application, and while it satisfactorily performs the function intended therefor, I have now developed a latching assembly which constitutes an improvement thereover in that the structural composition thereof is simplified. Consequently, an object of the present invention is in the provision of such an improved latching mechanism.

Another object of the invention is that of providing a stage having foldahle platform sections and elongated side rails, and in which a support assembly is provided for rigidifying the platform sections and side rails by defining a support connection therebetween. Still another object is to provide a stage of the character described, in which the support assembly is structurally simple, economical, and is readily manipulated so as to establish and release the support connection between the platform sections and'side rails.

A further object is in the provision of support linkage that is bodily movable between a retracted position wherein it is related in a generally contiguous planar sense to the respective side rails, and an extended position at substantially right angles to such side rails to define a support connection thereof with the foldable platform sections. Additional objects and advantages of the invention will become apparent as the specification develops.

An embodiment of the invention is illustrated in the accompanying drawing, in which- FIGURE 1 is an isometric view showing a foldable stage equipped with the invention, with the platform sections thereof intermediate their folded and extended position; FIGURE 2 is an isometric view similar to that of FIGURE 1, but showing the structure in the extended or open condition thereof; FIGURE 3 is an enlarged, broken perspective view of an end portion of one of the side rails; FIGURE 4 is an enlarged, broken side view in elevation of one of the side rails; FIGURE 5 is a further enlarged, exploded perspective view of the latchingcomponents of the support linkage; FIGURE 6 is a broken vertical sectional view illustrating the components shown in FIGURE 5 in the latching position thereof; and FIG-. I

URE 7 is an enlarged, broken perspective view of one of the hinge elements of the support assembly.

The stage shown in its entirety in FIGURES 1 and 2 is denoted with the numeral 3%, and comprises a generally rectangular frarne 11 having frame elements or

support panels

12, 13, 14 and 15 pivotally connected to the respective corners thereof. Carried by the frame 11 intermediate the side rails are a plurality of platform sectionsrespective ly identified with the numerals i6, 17,

18 and 19-that are movable between an open or extended position defining a horizontal, planar relation shown in FIGURE 2, and a folded or closed position in which the platform sections are oriented in vertical, facing relation. In FIGURE 1, the platform sections are shown intermediate the extended and folded positions thereof; and when they are fully folded, the panels 12 through 15 are swingable into positions disposed along the vertical planes of the sections to provide a compact structure that may be rolled on castors 20. It will be apparent that four castors are providedtwo on each end of the frame 11.

The platform sections are hingedly connected along the adjacent edges thereof, and each section is supported by the panels 12 through 15 on rollers (not shown) which ride on rails 21 with which each of the side panels is equipped. It will be noted by referring to FIGURE 4 that each of the side panels is equipped at the inner end thereof with a tubular hinge element 22 that defines a pivotal connection thereof with the frame 11. each of the panels at the opposite ends thereof is provided with a depending leg 23 that affords a support therefor. FIGURE 6 makes it clear that each of the foldable platform sections 16 through 19 is reinforced along the underside thereof with a U-shaped frame 24 which may be secured thereto by cap screws 25. For further details concerning the structural and functional characteristics of the foldable stage, reference may be made to my copending application identified hereinbefore.

By referring to FIGURE 4, it will be seen that the frame element or side panel 14 is provided at longitudinally spaced intervals with a plurality of support elements in the form of

hinges

26, 27 and 2.3, there being three in number in the specific illustration. Each of the hinge elements has a fixed component 29 welded or otherwise rigidly secured to the side panel 14, and a movable component 3d pivotally secured to the fixed component 29 by means of a pin 31. Secured to the forward face of each movable hinge component 30 is a generally L-shaped bracket 32 having a leg or ear 33 extending laterally from such component in a generally normal orientation with respect thereto. Pivotally secured to the bracket leglifi by a pivot pin 34 is an elongated link or lever 35.

The link 35 adjacent the outermost end thereof (as is shown most clearly in FIGURE 5) is pivotally connected by a pin 36 to an arm or bracket 37, fixedly carried by the web 38 of a gusset 3? of generally triangular configuration and which is provided with a tubular edge portion 4b. The tubular edge 40 defines a pivotal mounting for the gusset 39 about a shaft or pin 41 which extends through ears 42 and 43 provided by the side panel 14. The gusset 39 is swingable between the position thereof shown in FIGURES 1 and 4 whereat it extends along the plane of the side panel, and the position shown in FIGURES 3 and 6 whereat it is at generally right angles to the plane of such side panel.

It will be evident that such swinging of the gusset enforces movement of the link 35 along the longitudinal axis thereof, and necessarily moves the end thereof which Further,

is pivotally connected to the bracket 37 between positions of adjacency and spaced relation with the plane of the side panel. Since the link is also pivotally connected to each of the movable components 3% of the various hinge supports, these components must also be shifted thereby between the position shown in FIGURE 4 in which they are in substantially parallel juxtaposition with the side panel, and a position extending laterally therefrom and at generally right angles thereto. In t .is latter position, each of the components Stl is disposed beneath the lower flange of a platform frame 2 and abuts the same, whereby the platform sections are supported thereon.

In order to lock this linkage in the support position thereof, the gusset 39 is provided with a laterally turned edge or lip 44, and is notched or recessed as shown at 45 intermediate the ends of this lip. The recess pr ojects downwardly into the web 38 of the gusset and has a latch bar or receiver 46 extending thereacross which is adapted to seat within an arcuate channel 47 provided by a latching finger 48 secured to the web of the platform frame 24. The latching finger has a forwardly extending tongue 49 that moves through the recess 45 beneath the latch bar 46 extending thereacross when the gusset is swung outwardly from the side panel to seat the latching bar within the groove 47, as shown in FlGURE 6. It will be evident that a frictional interlock is defined by the latching finger 48 and latch bar 46 so as to maintain the gusset in its extended position.

Each of the side panels 12 through 15 is provided with a support linkage comprising hinge elements 26, link 35 and gusset 39, and the support linkage in each instance is identical. While each of the platform sections 16 through 19 is equipped with a support frame 24, only those frames for the outer sections 16 and 19' are equipped with latching fingers 48, and there will be a total of four such fingersone for each of the side panels 12 through 15 and, more specifically, for the respective gussets 339 provided thereby.

in use of the platform or foldable stage structure, and assuming first the completely folded position thereof which is not shown herein but may be seen in my copending application referred to hereinbefore, the side panels 12 through 15 are extended outwardly as shown in FIGURE 1 and the platform sections 16 through 19 opened (also as shown in FlGURE 1) to the horizontal planar position thereof illustrated in FIGURE 2. Next, the gusset 39 provided by each of the side panels is pivoted outwardly so as to extend laterally at right angles from the plane of the respective side panels to the position shown in FIGURE 6, wherein an interlock is established between the latching finger 4.8 and latch bar 46. Such movement draws the link 35 toward the left as shown in FIGURE 4; and since it is a rigid element which cannot be lengthened, the movable component 30 of each hinge support is swung outwardly into substantial parallel relation with the latched gusset. Thus, in being disposed beneath the frame of each platform section and in substantial abutment therewith, the hinge components define a support linkage between the platform sections and side panels. The stage may be folded simply by swinging each of the gussets inwardly to dispose the same in contiguous parallel relation with the side panels therefor, which then frees the platform sections and permits the same to be folded.

While in the foregoing specification an embodiment of the invention has been described in detail for purposes of making an ample disclosure thereof, it will be apparent to those skilled in the art that changes may be made therein without departing from the'spiri-t and principles of the invention.

I claim:

1. In a platform structure having a pluralityof hingedly related platform sections movable between a folded position and an open position defining a generally horizontal planarrelation and havingalsc-a plurality of stee nessfor supporting said sections in the open position thereof, a support assembly for each of said side panels for interconnecting the same with said sections when the sections are in the open position thereof, each of said support assemblies comprising a plurality of hinge elements having a stationary component fixedly secured to the side panel therefor and a movable component swingable between aretracted position along such side panel and an extended position at generally right angles thereto for receiving a platform section thereon, an elongated linkage for each of said side panels and being pivotally connected directly to the respective movable hinge components therefor and being bodily movable relative to the associated side panel both longitudinally therealong and inwardly and outwardly with respect thereto, a gusset for each of said side panels and being hingedly secured thereto for movement correspondingly coordinated with that of the movable hinge components, each of said gus-' sets being pivotally connected with the linkage therefor to enforce movement of said movable hinge components between the retracted and extended positions thereof, and means for latching each of said gussets in the extended position thereof.

2. Thestructure of claim 1 in which said means comprises a latching finger carried by a platform section and an interlocking receiver therefor provided by the gusset.

3. In a stage structure having a plurality of hingedly related platform sections movable between folded and open positions and having also a plurality of side panels adapted to support said sections in the open position thereof, a gusset hingedly secured to one of said side panels adjacent an end thereof for swinging movement between generally parallel and normal positions relative thereto, an elongated linkage pivotally secured at an end thereof to said gusset and extending therefrom longitudinally along said one side panel and being bodily movable relative thereto both longitudinally therealong and inwardly and outwardly with respect thereto, and a plurality of binge elements spaced apart along said linkage, each of said hinge elements being rigidly secured to said one side panel and having a movable component pivotal about an axis generally parallel to the axis of movement of said gusset, each of said movable components being pivotally connected directly to said linkage, whereby movement of said gusset shifts said linkage along the longitudinal axis thereof to enforce movement of each of said components corresponding to that of said gusset.

4. The structure of claim 3 in which latch means are provided for anchoring said gusset in the position thereof generally normal to the aforesaid one side rail.

5. The structure of claim 4 in which said latch means comprises a generally hook-shaped finger carried by one of said platform sections and a latch bar carried by said gusset for releasable interlocking engagement with said finger.

6. The structure of claim 5 in which said gusset is provided with a recess for receiving said finger therein, and

' in which said latch bar extends transversely of said recess.

7. The structure of claim 3 in which a generally L- shaped bracket is fixedly secured to each of said hinge components and defines the pivotal connection thereof with said linkage.

8. In a stage structure having a plurality of hingedly related platform sections movable between folded and open positions and having also a pair of transversely spaced and longitudinally extending side panels adapted to support said sections in the open position thereof, a pair of binge elements respectively associated with said said panels and having a fixed component rigidly secured thereto and a movable component pivotal about an axis generally normal to planes defined by said platform sections when said sections are in'the open position thereof, andalp'air of transversely spaced and longitudinally extending linkage structures respectively associated with said hinge elements and being pivotally connected directly to said movable components, each of said linkage structures being longitudinally reciprocable along the respec tively associated side panels and bodily movable inwardly and outwardly relative thereto and being efiective to swing the respectively associated movable hinge components between a first retracted position wherein such movable components extend along the associated panels and a second extended position wherein said movable hinge components are oriented transversely with respect to said panels and beneath said platform sections for supporting the same.

References Cited in the file of this patent UNITED STATES PATENTS 1,079,057 Meyer Nov. 18, 1913 2,668,331 Horn Feb. 9, 1954 2,841,831 Mackintosh July 8, 1958 2,860,383 Heisler Nov. 18, 1958 2,922,683 Schmertz Jan. 26, 1960