US3400502A

US3400502A - Telescoping platform structure

Info

Publication number: US3400502A
Application number: US581243A
Authority: US
Inventors: Robert T Scaggs; Henry A Meares; Lloyd D Lindsey
Original assignee: American Seating Co
Current assignee: American Seating Co
Priority date: 1966-09-22
Filing date: 1966-09-22
Publication date: 1968-09-10
Anticipated expiration: 1985-09-10

Description

Sept. 10, 1968 R. T. SCAGGS ETAL 3,400,502

TELESCOPING PLATFORM STRUCTURE Filed Sept. 22, 1966 z Sheets-Sheet 1 v JNVENTORS Robert 12 Scdqgs Henry A. Meqres Lloyd D. Lindsey ATTORNEYS R. T. SCAGGS ETAL 3,400,502

TELESCOPING PLATFORM STRUCTURE Sept. 10, 1 968 2 Sheets-Sheet 2 Filed Sept. 22, 1966 a I. nun- 0,. I I:

Ia mm m I: 0 03 F M I: H 1 4 .h. 3

INVENTORS Robert T. Sccggs Henry A Meares Lloyd D. Lindsey BY Q In Ji'tolbl la'zczvl 6 MAW ATTORNEYS United States Patent TELESCOPING PLATFORM STRUCTURE Robert T. Scaggs, Urbana, Henry A. Meares, Champaign, and Lloyd D. Lindsey, St. Joseph, IiL, assignors, by mesne assignments, to American Seating Company,

Grand Rapids, Mich, a corporation of Delaware Filed Sept. 22, 1966, Ser. No. 581,243 9 Claims. (Cl. 52-9) ABSTRACT OF THE DISCLOSURE Horizontal platforms in sections are arranged one over the other in telescoping relation for movement to expanded position or inwardly to contracted position, a first section having at its rear a pair of spaced pulleys on opposite sides thereof mounted for rotation in a horizontal plane and in the plane of the second section a pair of cables, each secured to the rear of the second section adjacent a side thereof and extending along said side and about the front portion of the pulley adjacent said side and about the rear portion of the pulley at the other side of said section, each cable being secured to the front portion of said second section. With this structure, the mobile sections which are free of outside support are individually guided in their parallel travel to the expanded and contracted positions.

This invention relates to a telescoping platform or bleacher structure, and is particularly useful in connection with sectional telescoping platforms used in auditoriums, athletic fields, stadiums, and the like.

Telescoping sectional platforms are highly useful in fields of sports, stadiums, and other areas in that the platform sections can be readily folded so as to occupy little space and thus afford larger free areas in the fields while, in times of exhibitions, the platform sections can be drawn forwardly to provide areas for receiving chairs, benches, etc. for seating spectators. In the operation of such sectional telescoping platforms which are usually of relatively large area, it is found that the sections tend to zigzag and bind in operation, thus requiring the services of several people and often damages the equipment and causing excessive wear in areas.

We have discovered that by the use of inexpensive pulley and cable means, it is possible to guide the platform sections so that they move accurately in alignment without binding, and further enable a person or persons to effectively open the sections or close them.

A primary object, therefore, is to provide ,a sectional telescoping platform structure in which the sections are guided for parallel movement toward open or folded positions. A further object is to provide in a telescoping platform structure having sections of varying heights, cable and elevated pulley means whereby the sections are guided for parallel movement without binding. Yet another object is to provide means for tightening the cables to provide taut cable sections for aligning and guiding the platform section. A still further object is to provide in a sectional platform structure cable and pulley guiding means permitting any selected platform section to be moved to any desired degree with respect to the other sections. Other specific objects and advantages will appear as the specification proceeds.

Summary By the use of inexpensive pulley and cable means, it is possible to guide the horizontal platform sections which are mounted one over the other for movement to and fro-m expanded positions without binding and without requiring support fro-m outside frame structures. On a first section 3,400,502 Patented Sept. 10, 1968 is mounted a pair of spaced cables on opposite sides thereof and at a point in the plane of a second section and a pair of cables each secured to the rear of the second section extend about the pulleys and engage opposite sides of the second section at the front thereof.

The invention is shown, in specific embodiments, by the accompanying drawings, in which FIG. 1 is a side view in elevation of a sectional platform structure shown in closed or folded position; FIG. 2, a broken perspective view of the sections shown in open or extended position; FIG. 3, a view similar to FIG. 2 but with the top of each platform section removed; FIG. 4, a perspective view taken from the front of the structure shown in FIG. 3; FIG. 5, a broken perspective view of the pulleys and cable portions attached thereto; FIG. 6, a broken top plan view of the third section equipped with cables and a rear portion of the second section equipped with pulleys mounted for rotation in a horizontal plane; FIG. 7, a sectional detail view, the section being taken as indicated at line 7--7 of FIG. 6; FIG. 8, a detail view, the view being taken as indicated at line S8 of FIG. 7; FIG. 9, a view similar to FIG. 6 but showing a modified form of structure in which the rear ends of the cables are secured to guide rails of the third section; FIG. 10, a sectional detail view, the section being taken as indicated at line 10-10 of FIG. 9; and FIG. 11, a sectional detail View, the section being taken as indicated at line 1111 of FIG. 10.

In the illustration given in FIGS. 18 inclusive A designates the lowermost or front platform section, B a second section thereabove, C a section above section B, and D the uppermost section. It will be understood that the platform structure may have any desired number of sections, but for the purpose of illustration here only four sections are shown. Each of the sections is provided with a top upon which chairs or seats may be placed, the tops being indicated by the letters A, B, C and D'.

As shown best in FIGS. 2 and 4, the front section A has side beams 10 supported on rollers 11 and equipped at its front with a depending member 12. At a point spaced from the rear of each beam 10 is mounted a verticallyextending crossbar 13 carrying at its top antifriction pad 14. The pads 14 support the upper beams 15 of the second section B, beam 15 being supported by the vertical standard 16 mounted on the lower beam 17 of section B. The lower beam 17 is likewise equipped with antifriction means 11 for supporting it together'with the standard 16, crossbeam 18 and the forwardly extending upper beams 15.

Section C is similar to section B having a lower beam 19 and an upper beam 20 and having a high mast 21 supporting the crossbeam 22.

Rails 15 of section B are provided at their front with a depending crossbar 23, and rails 20 of section C are provided at their front with a crossbar 24. Since the sections B, C and D are substantially the same in structure except for the varying heights of the masts carrying the crossbars, it is believed unnecessary to describe these structures in further detail. Telescoping structures of this type are well known in the art.

In accordance with our invention, we provide a lower section at its rear with a pair of double-grooved pulleys supported in alignment with a succeeding upper section, and the upper section is provided with cables secured to the front and rear portions thereof and extending about the pulleys to provide taut, parallel portions for guiding the upper section in its movement with respect to the lower section. For example, in FIGS. 6, 7 and 8, sections B and C are shown in assembled relation, with pulleys carried at the rear of section B and cables engaging the pulleys and secured to the front and rear portions of section C.

As shown best in FIGS. 6, 7 and 8,

pulleys

25 and 26 are supported on section B for rotation in a horizontal plane and they are engaged by

cables

27 and 28 carried by section C. The

pulleys

25 and 26 are supported upon brackets 29 by pivot pins 30, as shown in FIG. 7, the standard 16 being provided on its front side with the cross rail or beam 18 and on its rear side with the rail 18a to which cable 27 is attached.

Referring to FIG. 6, a cable 27 is secured to the rear rail 22a of section C and its extends forwardly around the front portion of pulley 25 and thence around the rear portion of pulley 26, and the end of the cable 27 is secured to the front rail 24 of section C by a threaded bolt 31 engaging a nut 32. Similarly, cable 28 is secured by an eye bolt to the rear rail 22a and it extends forwardly around the front portion of pulley 26 and thence around the rear portion of pulley 25, and the end of the cable terminates in a threaded member passing through an opening in rail 24 and engaged by nut 33. The

nuts

32 and 33 permit tightening of the

cables

27 and 28 to maintain them in taut condition. If desired, the adjustment bolts may extend through the rear rail 22a, instead of the front rail 24, so that nuts at the rear of rail 22a may be used to tighten the cables.

The arrangement of the pulleys and cables is illustrated in FIG. 5. Cable 27 passes around the front portion of the double-grooved pulley 25 and thence around the rear portion of pulley 26 and extends forward for attachment to the front rail 24 of section C. Similarly, cable 28 passes around the front portion of pulley 26 and thence around the rear portion of pulley 25 and extends forwardly for adjustable attachment to the front rail 24. In the preferred arrangement shown, the

cables

27 and 28 provide parallel portions extending from the rear of section C to the pulley aligned therewith so that as the lower section B is moved rearwardly, the pulleys engage such parallel portions of the cable and maintain the sections B and C in alignment.

Operation In the operation of the structure shown in FIGS. 1-8 inclusive, the sections A, B, C and D may be moved together or separately, and in such. movement the engagement of the pulleys carried by the lower section with the parallel cables carried by the upper section maintains the sections in alignment. As shown best in FIGS. 6-8, inclusive, each section A and B carries at its rear spaced double pulleys engaging parallel portions of the cable sections, and as one section moves with respect to the other, the pulleys traverse the parallel cable portions. To maintain the cables in taut condition, the threaded and attachments of the cables may be adjusted by

nuts

32 and 33, as shown in FIG. 6.

In the modification shown in FIGS. 9, and 11, the cable 28a is attached at its rear to a side rail a and it extends forwardly around the front portion of pulley 26a and thence about the rear portion of pulley a and is secured to the depending flange 34 of the platform member 35. Similarly, cable 27a is secured to the opposite side wall 20a and the cable extends forwardly along the side wall about the front portion of pulley 25a and thence around the rear portion of pulley 26a and is secured to the depending fiange 34 of the platform member 35. The

pulleys

26a and 25a are supported upon brackets 36 and carried by the section pulley.

While the

pulleys

25 and 26 and 25a and 26a may be supported at any desired elevation,'we prefer to support them by the use of brackets, as shown, at an elevated position in general alignment with the upper side rails of the succeeding section. For example, as shown in FIGS. 68, the pulleys are supported by brackets so that they are in alignment with the top rail 20 of section C, with the result that the pulleys are aligned with the cables which engage the rail 22a and front rail 24 of section C.

While in the specific illustrations given, we have shown the structures in considerable detail for the purpose of illustrating embodiments of the invention, it will be understood that such details may be varied widely by those skilled in the art without departing from the spirit of our invention.

We claim:

1. In a sectional telescoping platform structure, a plurality of telescoping platform sections including a first section and a second section in telescoping relation over said first section, said sections lying in a horizontal plane and spaced vertically from each other, said first section having at its rear a pair of spaced pulleys on opposite sides thereof mounted for rotation in a horizontal plane and in the plane of said second section, a pair of taut cables each secured at the rear of the second section adjacent a side thereof and extending along said side and about the front portion of the pulley adjacent said side and about the rear side of the pulley at the other side of said section, each cable being secured to the front portion of said second section.

2. The structure of claim 1 in which said cables extend in parallel from the rear of the second section and in alignment with the first-engaged pulley.

3. The structure of claim 1 in which said second section is provided at its front with a crossbar and said cables are secured to said crossbar.

4. The structure of claim 1 in which means are provided for adjusting the length of said cables to maintain them in taut condition.

5. The structure of claim 1 in which each cable extends from a rear corner portion of said second section to a diagonally opposite front corner portion of the said section but is looped about said pulleys to provide a guide portion substantially parallel to a side of said section.

6. In a sectional telescoping platform structure, a plurality of horizontal platform sections in telescoping superposed relation mounted on rollers for travel relative to each other, certain of said sections having on their rear portions spaced pulleys mounted on pivots for rotation in a horizontal plane, and parallel cables carried by sections over said pulley-equipped sections and anchored to the front and rear portions of said sections for engagement with said pulleys to maintain said sections in parallel paths during telescoping travel.

7. The structure of claim 6 in which the pulleys are double-grooved pulleys.

8. In combination, a first platform section, a second platform section supported for telescoping movement over said first platform section, said first section having at the rear thereof spaced elevated pulleys supported on vertical pivots in alignment with the front and rear portions of said second section, and cables secured near either side of said second section at the rear thereof, each of said cables extending around the forward side of the adjacent pulley and around the rear side of the opposite pulley and secured in taut condition to the adjacent front portion of said second section whereby when said second section is moved it is held in parallel relation to said first section.

9. The structure of claim 8 in which each section has lower and upper parallel sides and the pulleys of said first section are supported by brackets in elevated position aligned with the upper sides of said second platform section.

References Cited UNITED STATES PATENTS 1,519,355 12/1924 Brubaker 18752 2,849,085 8/1958 Hopfeld 18717 3,222,827 12/1965 Smith 52-9 3,279,131 10/1966 Curra 52-9 3,341,986 9/1967 Brosig 52-67 HENRY C. SUTHERLAND, Primary Examiner.