US2446372A - Metal tubular scaffolding - Google Patents

Description

9 W48 w. c. JONES EI'AL METAL TUBULAR SCAFFOLDING Filed Sept. 18, 1945 2 Sheets-Sheet 1 a a I INVQNTOR v Aug. 3, 1948; w. c. JONES ETAL METAL TUBULAR SCAFFOLDING 2 Sheets-Sheet 2 Filed Sept. 18, 1945 Patented Aug. 3, 1948 METAL TUBULAR SCAFFOLDING William Clifford Jones, London, and Leonard Sydney Richards, Soiihull, near England,

assignors to Scaflolding Birmingham, (Great Britain) Limited, Saunderton, England Application September 18, 1945, Serial No. 616,982

In Great Britain October 10, 1944 4 Claims. i

Since the introduction of metal tubular scaffolding for use in the erection of buildings it has been customary to transport to the site a quantity of loose tubes of various lengths, together with a supply of inter-tube couplers and other ancillary fittings, and there to construct the requisite framework piecemeal from the individual members at hand. Each stanchion or column has had to be constituted the requisite length, e. g. by coupling an appropriate number of tubes end to end, and the position of each coupler connecting two intersection members has had to be ascertained by trial and error during the course of erection. It will readily be apparent that a very large proportion of the cost of erection of a scaffolding by the aforesaid existing technique has been represented by the disproportionate amount of time which is occupied by the performance of the work, an amount of time which is frequently quite unwarranted by the simplicity of the completed structure, and the present invention is concerned with proposing a novel and improved method of and means for erecting scaffolding of the class referred to, whereby a notable economy in labour costs may be effected, and which will in general be more efiicient than the existing method of erection.

According to this invention a scaffold structure is composed of a series of prefabricated H- frames spaced apart in parallel relationship, so that each constitutes a pair of vertical columns tied by a cross-member, a pair of brackets incorporated in each H-frame, ledger members connecting adjacent H-frames and resting on and secured to said brackets, with or without putlogs carried across and fixed to the ledger members, the arrangement being such that the structure may beextended upwardly to form successive upper stages by erecting additional prefabricated H-frames with their uprights spigotted or similarly mounted in or on the upper extremities of the lower stage of H-frames.

The manner of erection of a scaffold, and the means employed therefor, in accordance with the said invention, are hereinafter more fully described with reference to the embodiments shown by way of example in the accompanying drawings. In said drawings, Fig. 1 is a general perspective view of a portion of a scaffold. Fig. 2 is a fragmentary side elevation, and Fig. 3 is a fragmentary perspective view, of a part of an H- frame, depicting the arrangement of the ledger bracket in relation thereto. Fig. 4 is a fragmentary section illustrating one method of mounting the upright of one H-frame in that of the corresponding H-frame of the next lower stage. Fig. 5 is a fragmentary section showing the adjustable foot of one of the uprights of an H-frame in the lowest stage.

.As will be seen by reference to Fig. 1, the scaffolding there shown is constituted by a, plurality of superposed stages each of which is composed of a number of H-frames disposed at right angles to the building-line and connected in spaced relationship by the ledger members. Putlogs, laid across the ledger members, and the cross-members of the H-frames, collectively serve to support the planks of a working platform. After erection of one stage of the scaffolding, the next stage may be constructed immediately above it, the H- frames of the two stages lying in the same vertical plane and with the feet of the H-frames of the upper stage spigotted in the upper extremities of the H-frames of the lower stage.

Each H-frame is conveniently fabricated from high tensile steel tubing or other suitable tubular stock, the length of the upright Hi and of the cross-member ll being standardized throughout. The uprights Ill and cross-member H may be attached by welding or, if desired, by hinged couplers (not shown) arranged so as to permit the frames to be collapsed into a small volume for ease of transport and economy of storage space. The H-frames are provided with integral brackets i2 by which the ledger members l3 are attached to the uprights of the H-frames and which are preferably welded in position as shown at it in Fig. 2. Said brackets l2 conveniently consist of a stamped plate bent and profiled to form a recessed support for a ledger member (Fig. 2), and a setscrew l5 carried in the plate is arranged so that when tightened (as by the aid of a tommybar) it cramps the ledger member is against the underside of the cross-member II and the profiled edges I21 of the bracket.- The brackets l2 are located immediately below the cross-member ll thereof, so that putlogs l6 laid across the ledgers I 3 will be in the same horizontal plane as the cross-member H, thus ensuring that the platform boards I7 supported upon the putlogs l6 and said cross-members II will be uniformly horizontal.

The ground surface upon which the scaflold is erected is rarely level. In order to take account of unevenness of the ground surface we may provide a separate set of H-frames for the lowermost stage. The tubular stock from which the uprights ll) of this particular set of frames is fabricated is preferably of greater diameter than the uprights ll) of the upper stage frames, and each upright it of the lower stage frames houses a telescopic leg 18 (Fig. capable of being slid endwise into or out of the lower end of the same. Means, e. g. pegs l9, are provided for adjustably fixing the sliding legs ii in relation to the uprights it! at any one of a wide range of alternative settings, at say three inches apart. A baseplate 20 screwed upon the foot of the telescopic leg 18 may be adapted for a fine adjustment in relation thereto.

The upper stage H-frame uprights are furnished with expanding spigots 2|, preferably of the known type described in British Patent Specification No. 368,474, so that they may be mounted in the upper extremities of the lower stage H- frame uprights in the manner depicted in Figs. 1 and 4. The lower stage H-frame uprights are fitted with welded sockets 22 of a size appropriate to receive the shank of the spigot 2 I.

The putlogs 16 used to support the ledger members l3 are preferably provided with slldable brackets IBI which can be adjusted to suit the spacing of the members [3.

The dimensions of the H-frames and the weight of these and the other members of the structure are preferably such that each component unit can comfortably be lifted and handled by one man. For example, H-frames six feet high and four feet wide, made from two-inch tubing for the upper stages and two-and-a-half inch tubing for the lowest stage, are found to satisfy this condition, so that one man can erect a two-stage scaffold unaided.

What we claim as our invention and desire to secure by Letters Patent is:

1. A scaffold structure composed of a series of prefabricated H-frames arranged in alignment in spaced parallel planes, each H-frame constituting a pair of vertical columns of tubular metal tied by a single cross-member permanently connected therebetween, a pair of brackets incorporated in each H-frame, and ledger members connecting adjacent H-frames and resting on and securec to said brackets, the arrangement being such that the structure may be extended upwardly to form successive upper stages by erecting additional prefabricated H-frames with their uprights mountedon the upper extremities of the lower stage of H-frames.

2. A scafiold structure as claimed in claim 1, comprising putlogs carried across and fixed to the ledger members.

3. For use in constructing a scaffold structure, a unit composedof two spaced parallel tubular metal uprights, a single cross-member of tubular metal integrally welded thereto to form an H- frame, and brackets integrally attached to the REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Heberling Jan. 8, 1907 Coplan Oct. 29, 1929 Anderson Nov. 27, 1934 Jones Apr. 5, 1938 Beatty et al Aug, 16, 1938 Uecker et a1 Aug. 16, 1938 Reiner u Mar. 26,1940 Causey Aug. 18, 1942 Attwood Nov. 21, 1944 FOREIGN PATENTS Country Date Great Britain Aug. 4, 1938 Sweden Aug. 22, 1939 Number Number

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