US2985253A - Scaffold structure - Google Patents

Description

M 1961 G. P. HOLLINGSWORTH 2,985,253

SCAFFOLD STRUCTURE Filed Sept. 22, 1958 2 Sheets-Sheet 2 INVENTOR ATTORNEK SCAFFOLD STRUCTURE George P. Hollingsworth, 1205 W. 47th St., Kansas City, Mo.

Filed Sept. 22, 1958, Ser. No. 762,567

3 Claims. (Cl. 182-17) This invention relates broadly to the field of'building repair operations, and refers more specifically to novel scaffold structure which obviates the need for a space consuming multitude of expensive units that must be placed in position prior to the beginning of the repair operation.

In the past when it has been necessary to carry out repair or constructions at a substantial distance above the ground floor, it has been common to erect or fabricate expensive and space consuming scaffold structures to provide a platform for the workmen so that they may reach various areas at relatively high levels. Such scaffold structures have been necessary in work which is conducted within a high ceilinged building, or on the outside of such buildings when it is desired to work on the outside of the building at relatively high points on the Walls thereof. The problem is especially acute in the repair or construction of areas Within a high ceilinged building because of the fact that substantially the entire fioor area of the building must be. filled with the scaffold structure in order that the workmen may have access to and freedom of movement with respect to the entire ceiling and areas of the walls adjacent thereto. Scaffolds of this type are quite expensive to purchase or lease and require considerable manpower and time to erect.

It is one of the important objects of the present invention to provide scaffold structure which can be placed in position either within a building or adjacent the outside wall thereof in a minimum of time and with a very small number of components being required, and which is universally adapted for all conditions which require a scaffold by virtue of the fact that it is provided with movable stages whereby it is necessary to provide upright scaffolding only along two opposed longitudinal walls of the room, or adjacent one external wall of the building, thus leaving the central portion of the room or the lower areas of the external wall completely free for other operations.

The invention contemplates the provision of scaffold construction wherein the upright scatfolding along opposed walls of the room is constructed to receive longitudinal shiftable carriages which are in turn constructed to support and firmly secure thereto an elongated stage extending across the width of the room under construction or repair to the end that the stage may be shifted across the roomalong the scaffold assemblies, thus to permit a workman on a stage to reach any portion of the ceiling or wall surrounding the ceiling without. intricate intermediate scaffold structures being necessary, and without requiring replacement of or shifting of the upright scaffolding.

A further important object of the, invention issto provide a stage construction which can beused interchangeablyas a carriage supporting structure .or stage, thus adding materially to, theuniversality of application of, the systern and reducing the number of components which must: be purchased orleasedfor any given job; i Still another object of the invention is to provide scaf- Stfltes Patent fold construction of the character described wherein the stage supporting carriages include releasable means for fixing the carriages in a selected position relative-the upright scaffolding or the carriage supporting members whereby to eliminate the danger of the stage shifting while a workman is standing or moving about on the stage.

Other important objects of the invention relate to the provision of a construction wherein the connection between the carriages and the supporting members therefor is one in which there is no danger of the carriages accidentally tipping free therefrom, but in which shifting of the carriages is accomplished with speed and facility; and to the provision of means on each of the carriages for releasably attaching thereto the stage so the accidental displacement of the stage from the carriage is effectively prevented, yet which permits ready disassembly when desired.

Other and further objects of the invention together with the features of novelty appurtenant thereto will appear in the course of the following description.

In the accompanying drawings which form a part of the instant specificationand are to be read in conjunction therewith, and in which like reference numerals indicate like parts in the various views:

Fig. l is a plan view of a preferred form of the instant invention illustrating three interconnected stages, one stage transverse to the other two and movably supportedthereon by the carriages of the invention;

Fig. 2 is a fragmentary side elevation of the embodimerit of the structure illustrated in Fig. 1; a I

Fig. 3 is an enlarged fragmentaryview taken generally along the line 33 of Fig. 1 in the direction of the arrows; I

Fig. 4 is an enlarged fragmentary view taken generally along the line 44 of Fig. 1 in the direction of the arrows; I

Fig. 5 is-an enlarged fragmentary and partially sectional view of the brake mechanism from a similar position as resulted in Fig. 4;

Fig. 6 is a view taken along the line 6-6 of Fig. 5 in.

the direction of the arrows;

Fig.7 is an end elevation of a scaffold construction embodying the concepts of the invention and illustrating a modified form of stage, including means for supporting workers at different levels from the same carriages;

Fig. 8 is a view taken generally along the line 8-8 of Fig. 7 in the direction of the arrows, and

Fig.9 is a perspective view of the clamping bar disassociated from the carriage.

As heretofore pointed out, the present invention has particular applicability to use within high ceilinged rooms or areas and consequently I haveshown in Figs. 1 and-2 portions of an arrangement designed for this purpose. The general arrangement encompasses a pair of elongated members broadly designated by reference numeral 10 which .are disposed in spacedparallel relationship and at some distance from one another as indicated by the break lines.

Each of the members 10 is supported in turn in an elevated. position by upright scaffolding towers 122 which maybe conventional inform, it being necessary only that towers 12 be so located as to support the elongate members 10 in parallel and equally spaced relationship. Each of the members it) includes a pair of equally spaced substantially parallel channels 13 and 14, each provided witha pair of parallel flanges 1'5 and 16 and a web 17 interconnecting the flanges.

shown in Figs. 1 and 4, spaced cross braces 18 rigidly interconnect corresponding webs 17 of the spaced channel members and serve to maintain the channels in correct parallel relationship. In order to provide sup- RD port for workmen permitting movement along and directly upon the members a floor is provided between the channels of the members 10 in the form of planks 19 which may be constructed of wood or light metals or other suitable materials. These planks are preferably screwed to the cross braces by metal screws 20, although obviously other connecting means may be employed.

Bridging across and supported at its respective ends upon the members 10 is a third stage member S, preferably identical to members 19. However, it may be any conventional stage having the requisite physical strength to support workmen intermediate its ends when supported only at the ends.

It will be observed that the transverse stage S is actually supported on the parallel stages by means of intervening carriages 21, one of said carriages mounted on each of the members 10 for longitudinal movement therealong. Each of the carriages Z1 is substantially U-shaped in transverse section, as is clearly illustrated in Fig. 4, having a pair of spaced parallel normally upright side frames 22 and 23 and an upper frame 24 interconnecting side frames at their upper ends; Upper frame 24 presents a substantially flat surface adapted for receiving the transverse stage member 10.

Each of the side frames 23 and 24 includes a pair of substantially triangular truss sections, each of which is provided with a roller or wheel 26 rotatably mounted on the lower apex thereof by means of stub axles 27. Thus, it will be observed that there are at least four rollers or wheels 26 which are rotatably mounted by the axles 27 on corresponding corner portions of the side frames. As illustrated in Fig. 4, axles 27 extend inwardly from the side frames 23 and 24 so that the rollers 26 are located between the side frames and are disposed within the channels 13 and 14 between the flanges thereof. The members 10 are thus track members for the carriages.

The transverse stage member S is clamped firmly to the respective carriages 21, in each case by a clamping bar 30. Each bar 30 is pivoted about one vertical post 32 rising from the carriage. Post 32 is threaded over a considerable portion of length and the bar is retained in one selected position on the post by retaining nuts 33 and 34 which sandwich the bar therebetween and which are, of course, adjustable upwardly and downwardly on the post to accommodate the bar to different levels above the carriage. Preferably post 32 is also pivoted about a horizontal axis as by bolt 35 which connects it to the carriage.

A second post 36, identical in all respects to post 32, is located on the opposite side of the carriage and is likewise pivoted at its lower end to the carriage as at 37. The resistance to rotation provided in the pivotal connection should be sufiicient that post 36 will normally stand upright unaided. The bar 30 is releasably connected with post 36 by means of a lateral notch or recess 36a in the bar (see Fig. 9). Clamping nuts 38 and 39 lie on opposite sides of the bar and ordinarily firmly secure the bar to the post. However, it will be evident that the bar can be disconnected from post 36 by simply loosening the upper nut 38 and swinging the bar away from the post.

The pivotal mounting of post 32 on the carriage has an important object in that when the bar 30 is disconnected from post 36 as above described, the bar can be pivoted upwardly away from the stage S as shown in broken lines in Fig. 2, thus making it considerably easier to handle the stage S, place it in position on the carriage and remove it therefrom.

Preferably the upper retaining nuts 33 and 38 on posts 30 and 36, respectively, are of a diameter sutficient to facilitate hand manipulation and may be knurled or fluted so that a good grip can be obtained and maintained.

Each carriage is provided with at least one locking mechanism (generally indicated at 40) which is operable to lock the carriage against further movement along its track member at any selected position therealong. The locking mechanism illustrated comprises a pair of jaws 41 and 42 forming a part of a scissors-like clamping arrangement. The jaws are arranged to lie respectively above and below the upper flange 17 of the track and are pivoted about a shaft 43 extending from and firmly secured to the carriage. To alternately cause the jaws to firmly clamp the flange or release it as desired by the workmen, there is provided a thrust screw 44 having threaded connection with jaw 41 and extending freely through a smooth and slightly tapered aperture 42a in the jaw 42. A collar 44a below jaw 41 and an enlarged head 44b above the jaw 41 cooperate to prevent longitudinal movement of the thrust screw relative thereto. The head 44b is apertured to receive a lever bar 45 which provides a means for rotating the screw to open and close the jaws as desired.

Preferably the pitch of the threads on thrust screw 44 is high enough that the jaws can be firmly clamped and released within the scope of less than one complete revolution of the lever 45. a

The operation and manner of use of the invention as described thus far is believed evident from the foregoing description. In the case of repair operations being conducted in a room, the towers 12 are located on opposite sides of the room and the track members 10 placed in position thereon adjacent the walls and at substantially the same elevation. Thereupon a carriage 21 is placed upon each of the-track members by running rollers 25 into the open ends of the channels 13 and 14, and the carriages are fixed in position by the manipulation of the locking mechanism 40 previously described. The transverse stage S is placed in position upon the carriages and tied thereto by bars 30.

It is obvious that the stage S can be moved to any position desired from one end of the track members to the other, thus making it possible to locate the stage at any intermediate position between the walls. The flooring on the tracks 10 provides standing space for workmen while working on those walls or when releasing the carriages for movement along the track members. The great advantage in the arrangement is that the center area of the room is left completely free of any scaffolding structures and yet the workmen may, by shifting stage S, have access to any portion of the ceiling.

A modification of the invention is illustrated in Figs.

7 and 8 wherein it can be seen that a stepped bracket,

broadly designated 101, is suitably secured to the lowermost space of the stage S. Stepped bracket 101 is preferably constructed of a single length of bar material which is bent to present a series of steps 192 interconnected by risers 103. Steps 102 are preferably positioned so as to be horizontal with the ground or floor when stage S is disposed'upon carriages 21. There are actually two brackets 101 secured to stage S and depending therefrom. Preferably the steps 101 of the bracket are of suficient width to receive a supplemental stage plank S which is in transverse relationship to the main stage S. In this manner either one or a number of secondary stages S may be placed in position upon steps 102 in transverse relation to the main stage S and at any one of predetermined elevations relative to stage S.

I Thus a workman may work on various portions of the ceilingor the like, which are normally lower at the corners thereof, without the necessity of lowering the elevation of the track members and Without the necessity of his bending over during the time it is necessary for him to work on the lower area. The invention as modified is particularly suitable for repair work 'on pitched It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim:

1. In a scaffold system providing elevated working surfaces, the combination of two pairs of spaced towers, a pair of elongate platform members bridging the upper ends of the respective pairs of towers, the platform members being disposed in spaced parallel relation and each providing a walkway between the towers which it bridges, track members carried by each platform member and running lengthwise thereof, a pair of mobile carriages on each platform member, each carriage having wheels engaging the track members and movable longitudinally thereof to different positions relative the towers, an elongate stage, and means for releasably securing the stage to the carriages in transversely extending relationship with said platform members.

2. In a scaffold system as in claim 1, the inclusion of means on each carriage for releasably securing the same to its platform member at any location therealong.

3. In a scaffold system as in claim 1, said track members being disposed below the level of the upper surfaces of said platform members whereby to provide a level working and walking surface on the platform members.

References Cited in the file of this patent UNITED STATES PATENTS 1,593,945 Macklem July 27, 1926 1,740,117 Pinckey Dec. 17, 1929 1,863,984 Hoelfeldt-Lund June 21, 1932 1,918,905 Grimm July 18, 1933 2,072,354- Biebel Mar. 2, 1937 2,623,614 Herr Dec. 30, 1952

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