US1593945A - Portable scaffold - Google Patents

Description

July 27 1926. 1,593,945

J. J. MACKLEM PORTABLE'SCAFFOLD Filed March 25 1925 I 0 L o IN V EN TOR. JOHN J. MA CKLEM BY 27M? 9%? ATTORNEYS.

Patented July 27, 1926.

A 1,593,945 PATENT OFFICE.

JOHN J. MACKLEM, OF LOS ANGELES, CALIFORNIA.

PORTABLE SGAI'I'OLID.

Application filed March 25, 1925. Serial No. 18,235.'

My invention relates to portable scaffolds, and the purpose of my invention is the provision of a portable scaffold capable of being readily assembled and" disassembled and movable from place to place without the necessity of disassembling, the invention including a platform or plank and means by which the platform can be effectively supported in any vertically adjusted position and against sagging or swaying, and in rigid I relation to a pair of ladders or other sup ports in such manner that a flat and uninterrupted surface is provided at the upper side of the platform to permit working thereon without fear of encountering projections of any character.

It is also a purpose of my invention to provide a portable s'cafi'old in which trucks or wheeled tables are provided for supporting the ladders for movement over a surface, and simple and eflicient means for detachably securing the ladders in upright position on the tables.

I will describe only one form of portable scaffold embodying my invention and will then point out the novel features thereof in claim.

In the accompanyin drawings,

Figure 1 is a view s owing in perspective one form of portable scaffold embodying my invention;

Figure 2 is an enlarged fragmentary vertical sectional view through one of the ladders shown in Figure 1, with the platform or plank in applied position thereto;

Figure 3 is a vertical sectional view taken on the line 33 of Figure 2.

Referring specifically to the drawings, in which similar reference characters refer to similar parts in each of the views, my invention, in its present embodiment, is shown as comprising a pair of base supports S and S which are in the present instance in the form of trucks'or movable tables and each of which includes a relatively broad body 15 of rectangular outline and provided at its underside with caflers 16 by which the base supports can be freely moved over a surface. Secured to the upper sides of the bodies 15 are strips or ribs 17 which provide elongated projections or heads which are adapted to be received in sockets 18 formed in the lower ends of the side rails 19 of a pair of ladders L and L Fastening members 20, in the form of hooked irons, are extended throu h the bodies 15 of the base supports at opposite plate 22 is a span the hooked end of the iron and thus sides of the strip 17 so that their hooked ends reversely' engage the lowermost rungs of the ladders L and L, strips within the sockets l8 and holding the ladders against sidewise movement on the base supports. 1

The upper ends of the ladders Land L are bridged by a platform or plank P provided at its opposite ends with pairs of fastening members, which fastening members each comprise a-hooked iron 21 and a plate 22. The hooked end of the iron 21 embraces one of the rungs of the ladder andthereby supports the latform on the rung, while the Justable on the hooked iron to confine the rung against displacement from the hook. Between its ends and on the under side of the platform is secured a rib or elongated projection 23 which provides attachlng means for a pair of clamping brackets 24 pivotally connected to plates 25 secured to the upper ends of brace bars 26. These bars 26 may be formed of any suitable material, such as wood, and are provided at their lower ends with fastenin members comprising hooked irons 21 and plates 22 of the same construction as the fastening members on the ends of the latform, these fastening members engaging ower rungs of the ladders L and L, as illustrated in Figure 1, to support the brace bars in inclined position.

The clamping brackets in the present instance are in the form of H-shaped castings so as to receive the rib 23 and to be clamped thereto by set screws 27 with pivotal connection between the brackets and the plates allowing the brace bars to assume the in clined position, while the brackets occupy vertical positions.

From the foregoing'construct'ion, it will be manifest that the platform P can be supported in horizontal position at any height thereby maintaining the on the ladders L and L to form a rigid con- I fl' the nd r "s aeaeeap aam -'"provide-gefieetive means ii iori attaching the p 1 brace bars; am; leaving the, npperj -siirfacei l ets-she" platform {devoidl oiiany -prejections and presenting a smooth and uninterrupted surface for the workmen. The pivotalconmotion between the brace bars andthe latform allows desired adjustment of the ars so that they mav be connected to any one of the ladder rungs and thus firmly held in any inclined position desired. I

The strips 17 of .the bodies 15 effectively co-oper-ate with the socketed ends'of the ladders to prevent sidewise movement-of the ladders on the base supports, the hooked .irons maintaining the .strips in engagement with the sockets to prevent upward movement ofthe ladders on the base supports.

Although I have herein, shown and described only one form of portable scafiold embodying my invention, it is to be undert ps,ei avario sehan esaad modifictitibfls be made yitimat-aaepaam iaromas ps1, scopelqffthe appendediiclaim;

I claim as my invention p In ascafiold, the combination with a; air

of ladders, a platform bridging the lad ers and having hooked membersenibracing one a each of the rungs ofthe ladders, a rib secured to the lower surface of the platform,

clamping brackets having pivotal connection with the rib, brace bars provided with hook members connected to one of the rungs,

plates secured to the upper ends of the brace bars and being pivotally connected to the clamping brackets and members slidably mounted on the brace bars and platform for holding the hook members. in embracing position with respect to the ladder rungs.

JOHN J. MACKLEM,

.,..'the --inventi0n: and the-1 spirit: and I: I I

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