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Publication numberUS3748798 A
Publication typeGrant
Publication dateJul 31, 1973
Filing dateMay 11, 1972
Priority dateMay 11, 1972
Publication numberUS 3748798 A, US 3748798A, US-A-3748798, US3748798 A, US3748798A
InventorsMackintosh C
Original AssigneeMackintosh C
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Foldable grandstand
US 3748798 A
A grandstand arrangement capable of being completely folded by means of a powered winch mechanism and cable entrained about pulleys staggered between the front and rear ends of the grandstand to effect an upward lift at each level and a complete folding of the arrangement. Spacers are also provided near the floor level to maintain a uniform folding between tiers thereby increasing its stability.
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Claims  available in
Description  (OCR text may contain errors)

United States Patent [1 1 Mackintosh FOLDABLE GRANDSTAND [21] Appl. No.: 252,260

[52] U.S. Cl 52/10, 52/109, 52/121 [51] Int. Cl E04h 3/14 [58] Field of Search 52/64, 67, 8, 9,

52/10, 109, 121; 160/84 R, 84 H, 84 V; 182/69, 152; 14/45; 74/521 [56] References Cited UNITED STATES PATENTS 1,460,597 7/1923 Maurer 160/84 R 2,147,564 2/1939 Vance v l 52/10 3,373,844 3/1968 Schafer... 182/69 X 1,708,113 4/1929 Allen 14/45 [451 July 31, 1973 2,205,624 6/1940 Horn .1 52/9 FOREIGN PATENTS OR APPLICATIONS 849,002 7/1952 Germany [82/152 775,760 5/1957 Great Britain 52]) 613,392 12/1960 ltaly 182/152 Primary Examiner-John E. Murtagh Attorney-Aubrey Hummer 6 Claims, 10 Drawing Figures PAIENIEnJum ma SHEET 1 0F 5 ma mj Nmw PAIENIED JUL 31 I973 SHEEI 2 OF 5 1 FOLDABLE GRANDSTAND This invention relates generally to a foldable grandstand and more particularly to such a grandstand capable of being easily folded into a collapsed condition with the use of a power actuated means.

In accordance with the present design, a grandstand has been devised to be folded into a compact space with the use of a power actuated cable means which causes the various platform sections at each level of the grandstand to be lifted upwardly during folding, in a simple, efficient and highly economical manner. Moreover, the cable is so arranged as to render the grandstand more stable during its folding operation; and, moreover, spacers are provided near the floor level of the grandstand arrangement to prevent the bottom thereof from folding too closely together and possibly causing the grandstand to be too bulky and top heavy.

To this end, the principal object of the present invention is to provide such a foldable grandstand for auditorium or similar uses wherein intermediate vertical frames are disposed between vertical frames which support the grandstand and are movable upwardly therealong by means of a cable which, when actuated by a powered winch mechanism, causes such upward movement during collapse of the grandstand.

Another object of this invention is to provide such a grandstand wherein the cable is entrained about pulleys arranged in a zig-zag manner at the lower end of these intermediate frames and on the support frames at an elevation higher than said lower ends, whereby the cable effects an upward movement of the intermediate frames during a collapse of the arrangement.

A further object of this invention is to provide such a grandstand wherein a pair of such pulleys are vertically spaced on the rearmost end of such supporting frames so as to more evently distribute the force applied by the cable during movement of the various support frames together during the collapse of the arrangement. I v

A still further object of this invention is to provide horizontal bracing means between the intermediate frames and the support frames near the floor level so that, when pivoted during collapse of the grandstand, these bracing means serve as spacers to prevent the bottom of the unit from folding together too closely and, possibly, causing the grandstand to be too top heavy.

Other objects, advantages and other features of the invention will become apparent. from the following description of the invention when considered in conjunction with the accompanying drawings, wherein:

FIGS. 1 (a) and l (b) are side elevational views showing a part of the grandstand arrangement in accordance with the present invention;

FIG. 2 is a side elevational view showing the grandstand arrangement in its folded or collapsed condition.

FIG. 3 is a front elevational view of one of the support frames taken along line 3-3 of FIG. 1 (b);

FIG. 4 is a front elevational view of an intermediate frame taken along the line 4-4 of FIG. 1 (a);

FIGS. 5, 6 and 7 are detailed views showing various details of the arrangement of FIGS. 1 (a) and l (b);

FIG. 8 is a top view of the FIG. 7 detail, taken along the line 8-8 thereof; and,

FIG. 9 is a detailed view, taken along the line 99 of FIG. I (a).

Referring now to the drawings, wherein like reference characters referred to like and corresponding parts throughout the several views, there is shown a grandstand arrangement generally designated 10 in FIGS. 1 a and l b which discloses six complete rows of a multi-tiered grandstand, it being understood that several additional rows may be included for the arrangement as shown in FIG. 2.

The grandstand comprises a plurality of vertical frames 11 the forward one of which 11 a being a rail structure for the occupants seated in row I on chairs of a design as, for example, shown in my related application, entitled Collapsible Chair.

A typical frame 11 is shown in FIG. 3, in front elevation, setting forth the details of the forward frame in row V. It should be understood, however, that the remaining vertical frames 11 throughout the arrangement are similar to that shown in FIG. 3, except that the type and number of cross-bracing members may vary depending on the specific frame height.

In FIG. 3, frame 11 comprises a pair of spaced vertical support members 12 having casters or other type wheels 13 mounted at their lower ends and being supported, when the grandstand is occupied, by means of blocks, such as 14. Vertical, horizontal and diagonal brace members l5, l6, 17, respectively, are interconnected in any normal manner to effect a stable and unitary support frame 11.

Horizontal support panels 18 are provided for each of the tiers and, as can be seen in FIGS. 1a and lb, the panels together extend between adjacent frames 11 and are hingedly interconnected therewith as at 19 for movement of each panel at each level toward their respective frames 11. Each pair of support panels 18 are also hingedly interconnected as at 21 with a transverse support member 22, as shown most clearly in FIG. 4, as comprising an element of an intermediate frame 23. As can be seen, such intermediate frame 23 is provided for each of the multi-level rows of the grandstand and is disposed centrally between adjacent support frames 11. Intermediate frame 23 further includes vertical members 24, the height of which depends on the row at which such frame is located. Each member 24 has a pulley 25 mounted at its lower end with the exception of members 24 in rows I and II, which are merely provided with a rounded end of rubber or some other similar type material. Vertical, horizontal and diagonal strut members 26, 27, 28, respectively, make up the remainder of each intermediate frame 23 as a structural unit, it being understood that fewer or more than the number of struts disclosed in FIG. 4 are used to provide a strong intermediate frame unit depending on the height of each tier of the grandstand in which it is used.

Diagonal bracing members 29 arev provided at each row of the grandstand and are each hingedly secured to a vertical support member 12 at one end and at its other end are hingedly secured as at 31 to a movable sleeve member 32 secured to each vertical member 24, as clearly shown in FIGS. 4 and 5. A sleeve 33, secured as by welding to the vertical member 24 is provided to act as a stop member for the movable sleeve 32 in the extended condition of the grandstand as shown in FIGS la and lb.

In addition to pulleys 25, another series of pulleys 34 are provided on each of the vertical support members I 12 at an elevation higher than the pulleys 25. Moreover, an additional pulley 34a is mounted on the member 12 for the first tier I at a level slightly lower than the pulley 24 thereon, while yet another pulley 34b is provided at a high elevation on the vertical support member 12 for the last tier as shown in FIG. 2. Each of the pulleys 34 is mounted on a rod, as shown in FIG. 9, which is bolted in place as at 37 on support member 12. The pulley is permitted to move slightly along its rod within a peripheral groove thereon, as shown, thereby being capable of moving a small degree relative to their supports 12 during collapse of the grandstand.

A cable 38 is provided for moving the vertical frames 11 toward one another to effect a full collapse of the grandstand as shown in FIG. 2. To this end, the cable 38 is secured at one end to frame 11a and is entrained about each of the pulleys 25, 34 and about the lower ends of the uprights 34 tiers I and II, with the opposite end of the cable being secured to a cable drum 39. The drum is driven by means of a motor 41 mounted in any convenient location on the grandstand and through belts 42, as clearly shown in FIGS. 2 and 3.

Horizontal brace members 43 are provided between adjacent pairs of frames 11, in a manner whereby each of the braces 43 is pivotally secured at one end to a vertical support member 12 and, at its other end, to the lower end of a vertical upright 24. The pivotal connection for the members 43 with the vertical members 12 is shown in detail in FIGS. 7 and 8. Also, horizontal brace members 43a are provided for additional horizontal support for those tiers of relatively high elevation, such as V through X. Members 43a are pivotally secured at their opposite ends to members and uprights 24 in a manner similar to that described for members 43.

As partially shown in both FIGS. lb and 2, it may become necessary for stability purposes to provide more than a single set of diagonal bracing members 29, for the higher grandstand tiers. Accordingly, two sets of bracing members 29 are shown for row VII, as well as for row X.

Turning to FIG. 2, it can be seen that the manner of collapsing the grandstand so as to move the frames 11 toward one another, may be carried out by actuating the motor 41 for rotating drum 39 in a counterclockwise direction thereby moving the opposite ends of cable 38 toward one another. It should be pointed out that, in the interest of clarity, only several of the horizontal braces 43 and diagonal bracings 29 are shown since such bracing members function in a similar manner for each of the grandstand tiers. As the opposite ends of the cable are moved toward one another, each of the grandstand tiers are made to collapse, as the pairs of support panels 18 thereof begin to fold upon one another during an upward movement of vertical members 24. This upward movement of each member 24 is effected at relatively the same time by means of the force exerted by the cable in an upward direction as its length begins to shorten between adjacent frames I I. It can be seen that the staggered location of the pulleys 25, 34, for each of the grandstand tiers, permits the cable at each level to exert an upward force against the bottom of each vertical upright 24 which thereby lifts the transverse member 22 and causes a folding of the pairs of support panels in the manner as shown in FIG. 2. The free floating pulleys 34 are able to move along their respective bolts 37 during the collapsing operation of the grandstand thereby avoiding any possibility of misalignment between the cable and these pulleys.

Also, the horizontal brace members 43 pivot at their opposite ends during folding into a position shown in FIG. 2. These horizontal braces thereby serve as spacers for each tier of the grandstand to prevent the bottom of the grandstand arrangement from folding together too closely and causing the arrangement to be too clumsy and top heavy when completely folded. Moreover, the use of a pair of spaced pulleys 34, 34b on the rearmost vertical member 12, increases the stability of the grandstand during the collapsing operation since the force exerted by the cable is distributed between high and low elevations on the grandstand, thereby minimizing a toppling-over of the unit during its collapsing operation.

In order for the vertical frames to move without impairment during the collapsing operation, swivel caster wheels 13 at the lower ends of members 12 may be provided to avoid any slight misalignment between the grandstand tiers during the collapsing operation. In the alternative, guides or tracks may be provided on the floor to assure that the grandstand arrangement will not move from side to side during the collapsing operation.

From the foregoing, it can be seen that a grandstand arrangement has been devised which is relatively uncomplicated in its construction, yet is capable of being collapsed with the use of a power actuated cable which causes an upward lifting of intermediate frames and a folding of horizontal panel pairs between support frames, in an efficient, economical and highly effective manner.

Obviously, many alterations and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appendent claims, the inventioned may be practiced otherwise than specifically described.

What is claimed is:

l. A grandstand arrangement comprising a plurality of vertical frames resting on the ground at their lower ends between an extended and a collapsed position, a pair of horizontal support panels extending between adjacent frames and being hingedly connected thereto and to one another to permit a folding of said panels on one another during grandstand collapse, said panels lying in a different horizontal planes between adjacent frames thereby defining a multi-tiered grandstand, vertical support frames intermediate said vertical frames, horizontal bracing means and diagonal bracing means extending between said intermediate said vertical frames, means for moving said vertical frames toward one another comprising a pulley mounted at the lower end of each said intermediate frame and mounted also on said vertical frames at an elevation higher than at said lower ends, a cable secured at one end to the fore most one of said vertical frames and at its opposite end to a power operated winch, mounted on one of said vertical frames, the cable intermediate said ends being guided by and entrained about said pulleys, whereby, upon movement of said cable ends toward one another by means of said winch, said intermediate frames are moved upwardly with respect to said vertical frames as said panels are folded.

2. The grandstand arrangement according to claim 1, wherein said vertical support frames each include vertical support members and wherein said diagonal bracing means include diagonal brace members hingedly secured at one end to said vertical frames and at their opposite end to said vertical support members, and said wherein each said intermediate frame includes a transverse support member, each said pair of panels being hingedly secured to each other through their respective transverse support members.

6. The grandstand arrangement according to claim 2, wherein said horizontal bracing means comprise horizontal brace members pivotably secured at opposite ends to the lower ends of said vertical support members and to said lower end of said intermediate frames, respectively.

Patent Citations
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US1460597 *Aug 16, 1921Jul 3, 1923Maurer Herman WCollapsible wall
US1708113 *Jun 29, 1927Apr 9, 1929Allen Alvah KCollapsible tower
US2147564 *Aug 11, 1937Feb 14, 1939Vance Ella MFoldable structure
US2205624 *Apr 2, 1938Jun 25, 1940Horn Paul EFolding bleacher seats
US3373844 *May 16, 1966Mar 19, 1968George F. SchaferCompact motorized scaffold arrangement
*DE849002A Title not available
GB775760A * Title not available
IT613392A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5018452 *Dec 15, 1988May 28, 1991Henri ChauvetDrive system for track mounted undercarriages and method for use thereof
US5379556 *Jun 17, 1993Jan 10, 1995Macintyre; James R.Folding grandstand
US5467840 *Aug 18, 1993Nov 21, 1995Charron Sports Services, Inc.Drive unit for movement of telescopic seating system
US5787647 *Jun 7, 1996Aug 4, 1998Wenger CorporationPortable riser
US5901505 *Apr 3, 1998May 11, 1999Wenger CorporationPortable riser
US6625932 *Mar 3, 1999Sep 30, 2003Dexter LittlefieldVariable rise vertically retractable arena seating assembly
US7703257 *Nov 7, 2006Apr 27, 2010Jorge Tomas Cueli LopezMobile structure for adapting surfaces
US7900402 *Oct 4, 2006Mar 8, 2011Stageright CorporationPowered dual level telescopic seating riser assembly
US8782959May 22, 2013Jul 22, 2014Stageright CorporationPowered telescopic seating riser assembly
U.S. Classification52/10, 52/121, 52/109
International ClassificationE04H3/12
Cooperative ClassificationE04H3/126
European ClassificationE04H3/12C