US1712942A

US1712942A - Collapsible ladder

Info

Publication number: US1712942A
Application number: US243296A
Authority: US
Inventors: Hiram K Smith
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-12-29
Filing date: 1927-12-29
Publication date: 1929-05-14
Anticipated expiration: 1946-05-14

Description

H. K. SMITH COLLAPSIBLE LADDER Filed Dec. 29, 1927 May 14, 1929.

llatented May 14, 1929.

entre sra'rs Hman ir. sieren, or nnrnorr, ivricncrean".

COLLAPSIBLE LADDER.

Application filed December 939, 1927.

This invention relates to an extensible and collapsible ladder, and its object is to provide a construction which is such that the same may be so collapsed as to take up a minimum space, may be quickly manipulated, light in Weight, rigid in construction and cheap to manufacture. A further object is to provide an ellicient locking` means for locking the relatively movable parts in the position to Which they are adjusted and which locking means is concealed and readily adjustable, and so positioned as to permit et a maximum extension and collaps ine; movement ot the ladder section.

ldith the above and other ends in vie'vv, the invention consists in the matters hereinafter set forth and more particularly pointed out in the appended clair-n, reference being; had to the accompanying dran/'ingl in which- Figure l is a liront elevation of the ladder in extended position with parts broken away to shorten the figure;

lille". 2 is a similar vieiv showing the ladder in collapsed condition, and

3 is an enlarged sectional vievv of a portion et the ladder showing)` the locking means in elevation.

it ladder embodying?)1 the present invention comprises a series olf sections the side mem bers ol which are preferably olf tubular con struction, these members of each section bei oi'i a diameter to lit and slide Within the tubular members et the section below. 'lhc tubular side members o l' each section are connected by a single transverse member or rung` and it is the particular positioning` or connection olf this rung,` to the side members ci: each section Which permits olf a maximum p sing),I movement et the sections.

Els shown in the drawing` a bottom section l comprises tubular side members 2 olf the desired diameter and length and these side members are connected by transverse tubes il and d, the ends ol' which are rigidly secured te the side members, preferably by Welding the ends et the tubes 3 and l to the adjacent sides of the tubes 2. The overall lengrth of the side members 2 is such that the ladder "when collapsed may be easily handled and will not be of such a length as to be unwieldy. The members 3 and l form rungs coimectinp,` the side members 2 and the upper rung t is positioned at the extreme upper ends of the members 2. The lower ends of the side members 2 are provided with caps 5 which may be of rubber or other suitable Serial No. $343,296.

material adapted to prot-ect the surlfaco upon which the ladder is set and cover the lower ends ol" the members 2 to prevent them from injuring,- that surl'ace and also to prevent: the foot el the ladder from slippingivvl en it is set up. i

The section G ol'i the ladder directly above the loot section comprises tubular side members 7 oit a diameter to lit and slide `l-reely Within the members 2 and these side members 7 are (connected together at their oxtreme upper ends by means ot' a transverse tubular rung corresponding to the rung` Ll. The section 6 may therefore telescope Within the section l to nearly its lfull length, or until the rung;` l strikes the upper ends el? the tubes 2.

Sections similar to the section t3 are providedthereabove, each section having side members 7 et tubular term which are et an external diameter to lit and slide freely Within the tubular side members ot the next sect-ion below and the ladder is thus made of a series of sections, each arranged to tele scope Within the section belovv and the number of sections is such as to provide the desired length for the ladder7 the single ruim or transverse member which connects the side members of each section being positioned at the extreme upper end oi said side members to that section so that the maximum olf tele scopie movemciit olf the several sections is secured.

'llhe upper ends oit the extreme upper scction may also be provided with knobs t3 simin lar to the knobs to prevent injury to the surface against which the ladder is when the same is in use.

To loch the several sections in, their eX- tended or collapsed position, locking means is housed within each upper rune' el each section said lockingmeans comprisinp,l a rod 9 adapted to telescope Within a sleeve or tube l0, said rod and tube being positioned and held axially Within the rung` l by means ot bearing disks ll Welded or otherwise secured Within the tubular rung adjacent each end thereof and sleeved upon the rod 9 is coiled spring l2 interposed between a laterally eX- tending linger piece 18 on the rod and the adjacent end et the sleeve l0, said sleeve l0 is also provided with a nger piece la at its inner end and these finger pieces project laterally through a slot in 'the lovver side of the tubular rung. The outer ends et the rod 9 and sleeve l() are adapted to engage lOO within openings 16 in the tubular side members 7 of the section above, the Wall of the tubular side members of this section below to which the rung 4 is Welded at its ends, beingl cut away at the end of the rung so that the ends of the rod 9 and sleeve l0 may engage freely Within these openings 1G and prevent further relative movement of the sections. When the several sections collapsed or telescoped, to the position shown in Fig. 2, the ends of the locking rods and sleeves engage Within the openings in the side members of the sections and thus locl; the several sections in the position to which they have been adjusted. VWhen the la -is extended to the position shown in Fig. l rthe rods 9 and sleeves l() of the several loci;-

ing members positioned .vithinthe several rungs, engage other openings in the side members of the sections and thus hold these sections in the position to which they are extended.

With this construction and arrangement a very strong ladder is provided which may be collapsed into a small space and which is constructed entirely ci: thin tubing, making it very strong and rigid, yet light to handle. Such a ladder is particularly adapted for use by electricians and others Working Within a building Where it is necessary to move the ladder trom place to place and where it is desirable that such a. ladder may be collapsedl into a small space, further .facilitating its convenient handling. By welding the tubular rungs to the tubular side members, the ladder may be cheaply constructed and by locking these rungs at the extreme upper ends of the several sliding sections the maximum of telescopic movement is secured. Further by locking the locking means Within the several rungs, such locking means is concealed and protected against injury, at the same time facilitating the adjustment thereof and permitting of a maximum ot' collapsing movement, said locking means because of its location Within each rung being out of the Way of the adjacent sections where it dees not interfere with the full collapsing movement of the sections. The only portion of the locking means Which projects from cach tubular rung, are the ingers 13 and la and these fingers extend downwardly through a slot in the rung in such a position that they do `not interfere with the full collapsingmovement of the section above, the rung of that section lying parallel With and close to the rung of the section below when said sect-ions are iully collapsed. These iinger Ypieces are alivays in a position Where they ma be readily grasped by thc operator to Witidraw the ends of the rod S) and .sleeve 10 from the opening 1G and the spring lil exerts torce tending to move the rod and sleeve relatively in opposite directions so that their ends will snap into the openings when the sections are moved to brine' the opening 16 into position to be enV thereby.

)bviously the side membeiw: of each avec. tion of the ladder may be other than cylindrical in cross section and the rungs oil die ladder may have any desired cross sectional configuration but preferably all et diese members forming the ladder are tubular. (he side members for tclescoping` niovennini, and the runef members for receiving and concealA ing the roel-:ing means. Other changes may be made Within the .scope ol the apprnded claim Without departing troni the spirit oi the invention and l do not theretori` limit myseliI to the particular construction shown.

Having thus fully described my inveniiou what I claim is A ladder comprising a toot section having tubular side members connected by a plurality of rungs, the upper of said rangs being tubular and secured at its ends io the side members at the extreme upper end oilt said side members, a series of sections each coniprising tubular side members oi a diameter to iit and slide within the tubular side nie1nbers of the adjacent section below, and said side members being` connected at their extreme upper ends by a single tubular rung, locking means housed within each of the tubular rungs and comprising a locking;` rod and a locking sleeve to receive the :uljacent end of said rod, said rod and sleeve having laterally projeetinggf iingers and a coiled spring sleeved upon the rod between the iinger thereon and the end ot the sleeve, said tubular rung` being formed with a longitudinal slide intermediate its ends through which the fingers proj ect laterally and doivn- Wardly from the sleeve and rod, said tubular side members ot each section being` iormcd With openings to receive the ends ot the locking rod and sleeve. and caps on the lower ends of the side men'ibers of the .lower sections.

In testimony whereo't` I ailix my signature.

HIRAM l. SMITH.

lill) liifi