US2186484A - Folding scaffold - Google Patents

Description

Jan. 9, 1940. GUNTHER 2,186,484

FOLDING SCAFFOLD Filed Feb. 28, 1939 BY FREDP/CH J. GU/VTHEQ ATTORNEY.

25 selected degree of extension;

Patented Jan. 9,1940

2,18 ,454 FonmN sc FoLn Fredrich J. Gunthe oliv -Calif. p i ti li b al 28, ;1 9E;Q, $erial No. 258,8 2 36. '1. Claim. "(e-1.23044) This invention relates to scaffolds of thefself sustainingtype, and more particularly-to a trestle which canbe folded-to facilitate transportation thereof, and which is adjustable as to heightiso 5- as to adapt it to supportwork and/or workmen at different elevationsa An object-oi my invention is to provide a trestle v of convenient and compact form, which, while I being amply rugged tofserve adequately as a car- Penters horse or work bench, or 'as a scafiold for painters, carpenters, lathers, ,plasterers, or substantially any type of workmen: called upon to work in locations not conveniently'reached from the floor or ground, and yet which is adapted to 9' fold into compact form and is stuficiently light construction tobe readily portable.

.Another objectistoprovide a folding horse or trestle of the character described-the legslof which are extensiblesoasto adapt it :for the 20 performance'of work at several difierenteleva- 'tions. a i

. A further object of thisfinventionisto provide a locking device of novel and highly-cili -cient design, for. releasably' fastening the legs in A still furtherobject of my invention istoj provide a folding and extensible horse or trestle of I the general, character indicated, which is 1 of simple, rugged, and durable design, and which can 30' be produced at low cost even in relatively small quantities, so as to adaptit for production and I sale by a private individual'and/or small organization without requiring the; outlay of any large sum of money l. 35 The invention possesses other objects andad- 'vantageous features, someof which, with those enumerated, will be set forth in the following description of the inventiohs particular embodiment which is illustrated in the drawing accomiO panying and forming' a part of the specification.

Theform of construction herein disclosed, has

in actual useprovento be very: efiicient, amply rigid, capable of facile and rapid'produotion, and generally desirable in" other respects.- For these 45 reasons, the details herein disclosed may be considered as preferred. It should be mentioned,

however; that While these details will hereinafter be specifically described, variations may be effected within the scope of the invention asclaimed. 1 p I "Referring to the drawing: r I .Figurelis a 'view inside elevation of a folding trestle incorporating the principles of the pres-f 55 ent'invention.

i -Figure 2 is aIlhd'e1eVatiOn, the d re t on of view being indicated by the arrow 2 of Fig. 1.

, Figure 3 is an enlarged detail view in horizontal section, the plane ofsection being indicated r bythe line 3-3 of Fig. 2 with the direction of ,5

. view as indicated by the arrows.

Figure {l is an enlarged detail View in vertical section taken upon the line G -Jl of Fig.g-3 with the direction ,oflview as indicated.

Figure 5 is a perspective view of one end of 10 the device, portions of the figure being broken aw-ay'to reduce its sizes t I I'n 'its preferred embodiment, the folding I scafio ld of my'invention comprises a horizontal top member 6, which may be conveniently. formed p of wood, as a board of suitable standard-dimer sions has -been found to fulfill the requirements ofthe ,top member, Associated witheachend of thetop, member Bis a leg assembly 1, each pivot- U ably connected adjacent its upper end to the top memberiin any convenient mannen'as bya'pin 8-extending through eachleg 9 of the upper ladder H (which willbe fully described-,jhereinbelowyand through an angle bracket 52,; one of v a whichis provided adjacent eachof thev fourcor- I ners of the top memberfi onv its under surface. The pins 8 ofjeach of the leg assemblies are axi ally-aligned, so that each leg assembly can optionally be. swung to. top-supporting position, 3

' wherein it-extends-downwardly and outwardly 3o from the topmember 6, as illustrated iniull lines in-Fig. 1, orto folded or retracted position, closely underlyingthe top member 6, ,as illustrated n broken lines inthat figure. Preferably thegparts are so proportioned and arranged that when the leg assemblies! are folded," their lower ends are I disposed closelyadjacent each othenfso as to make *availablethe maximum length of support ingleg members for a given length of top memberG. I A flexible tension membensuch as a' length of cable 13, is attached at; each end to one of the leg assemblies 'l at apoint spaced from the associated pivot'pins 8;" and this cable is of such length that when stretched; taut, it permits the leg assemblies to spread outwards slightly from v the vertical, so as to add stability tothe structure.. A pair of compression members M are also provided, each. comprising a brace pivoted at its lower, end to one of the leg assemblies and adapted to be rer'n'ovably secured to the top member 5 as by a laterally extending finger. l6 rigid wlth' the brace at its upper endandreceivable within aneyleg l l on' the'under side of the top member 6 adjacent its center. A cotter pin l8, or its Each of the leg assemblies comprises an upper ladder member II and a lower ladder member 2| slidably mounted thereon in telescopic arrangement which permits adjustment of the leg assembly to that degree of extension appropriate to the particular work to be performed. Each of the upper ladder members comprises apair;

of legs 9 retained in spaced parallel arrangement by a plurality of horizontal steps 22; and each lower ladder member 2| is similarly comprised of legs 21 retained in spaced parallel arrangement by horizontal steps 24. The steps 24 of the lower ladder member are slightly longer than the steps 22 of the upper ladder member II, with the result that the legs 23 of the lower ladder 2| receive the associated upper ladder member 2| therebetween where it is retained by being slidably engaged between the inner faces of the steps 24 of the lower ladder member 2| and brackets 26 rigid with the lower ladder member 2| and embracing the inner faces of the legs 9 of the upper ladder member H (see Figure 3).

Means are provided for releasably locking each of theleg assemblies in selected degree of extension. A rod 3| is carried by each lower ladder member 2|, preferably adjacent the uppermost step 24 thereof. Each of these rods 3| is bent substantially to U-shape, the ends of the legs 32 of the U being pivoted to the legs 23 of the associated lower ladder and in axial alignment so that the portion 33 joining the legs can optionally be swung under any one of the steps 22' of the upper ladder member to retain the upper ladder in selected raised position with respect to the associated lower ladder, or withdrawn therefrom to permit telescoping of the upper ladder within the lower ladder. Instead of being straight, however, each leg 32 of each of the U- shaped rods comprises three sections angularly disposed with respect to each other. The substantially upright portion 36 is connected at its upper end with a laterally extending portion 31, which in turn is connected with an inwardly extending portion 38, to which the portion 33 of the rod is connected. The upright portion is pivoted at its lower end to the inner face of one of the legs 23 ofthe associated lower ladder 2|, in position for the upright portion to engage the outer face of the associated leg '9 of the upper ladder and the laterally extending portion 31 is of suitable length to offset the inwardly extending portion 38 far enough from the upright portion to extend inwards substantially parallel to the inner face of the associated leg 9 of the upper ladder ll.

Instead of engaging directly against the under face of a step 22, however, I prefer that this inwardly extending portion 38 of each of the rods 33 engage between spaced flanges 4| and 42 which extend inwards from suitable brackets 43, one of which is fastened under eachend of each step 22 of each upper ladder II. A third flange 44 on the upper end of each bracket 43 supports the associated end of the associated step 22.

By raising the upper ladder II of either of the leg assemblies Tslightly higher with respect to the associated lower ladder than desired for any particular extension of that leg assembly, the inwardly extending portions 38 of the associated rod 33 can be interposed between the vertically spaced flanges 4| and 42 by two aligned brackets 43, with the result that when theupper ladder ll subsequently slides downward: upon its lower ladder, the upper flanges 42 bear against the inwardly extending portion 38 of the rod 33. This makes the upright portions 36 swing inward until they engage the outer faces of the legs 9 of the upper ladder H, and when such engagement occurs, further swinging of the rod is prevented, withthe result that the downward movement of the upper ladder is arrested.

Thus it may be seen that each leg assembly can be adjusted independently of the other, to make it any desired length within the limits of its extensibility. Hence, one leg assembly can be made longer than the other to let it rest on the floor while the other rests'on a step or some other support higher than that upon which the longer assembly rests, and still support the top member 6 in substantially horizontal position.

Preferably the rods 33 and the brackets 44 are of such design'that the upper ladder is supported thereby with its steps 22 in alignment with the steps 24 of the associated lower ladder, as this facilitates the use of the leg assemblies as a means of access to the elevated top member 6.

I claim: a

A folding trestle of the character described, comprising a horizontal top member, and a leg assembly pivotally secured adjacenteach end thereof and adapted to be optionally moved to folded position underlying said top member or to top-supporting position extending angularly downwards and outwards therefrom, each of said leg assemblies comprising an upper ladder with which the pivotal connection for that assembly '2:

is associated, a lower ladder slidably mounted thereon for telescopic adjustment with respect thereto, and means for releasably locking said ladders in selected degree of extension comprising a rod bent to present at each end thereof an upright portion, an inwardly extending horizontal portion, and a laterally extending horizontal portion joining the upper end of said upright portion and the outer end of said inwardly extending portion, each of said upright portions being pivotally connected to one leg of one of said ladders and said pivotal connections of said upright portions being axially alignedwhereby said inwardly extending portions andthe central portion of said rod joining them can be dispos 1;,

under a step of the other ladder of the associated leg assembly 'with said upright portions engaging outer faces of one of said ladders to limit downward movement of said inwardly extending portions, and a bracket affixed to each leg of said other ladder under each of said steps thereof, each of said brackets comprising a plate affixed to the inner face of the associated leg, a flange projecting therefrom and supporting one end of one of said steps, and a pair of vertically spaced flanges spaced below said step-supporting flange and adapted to receive one of said inwardly extending'portions of said rod therebetween.

FREDRICH J. GUNTHERl

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