US522526A - Adjustable scaffold - Google Patents

Description

D L 0 P am NW I Km M MT 8 U J D A (No Model.)

Pate nted July 3, 1894.

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i UNITED STATE-s PATENT OFFIC J MoN oEKING, on PRINCETON, INDIANA.

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SPECIFICATION forming partof "Letters Patent l lo. 522,526, dated July 3,1894. 7

Application filed-Tune 17 11892 Renewed ll'une 7, 1894; s ialN 513,833. (No model.)

To all whom itmay concern: 7

Be it known that I, MONRoE'KING,a citizen of the UnitedStates, residing at Princeton, in the county of Gibson and State of Indiana, have invented certain new and usefullmprovements in Adjustable Scafiolds, of which thefollowingisaspecification,referencebeing had therein to the accompanying drawings.

This invention relates to a new and improved extensible scafiold; and it has for its object to provide a scafiold of simple construction, which may be readily raised or lowered, and extended in length when desired.

In the drawings: Figure 1 is a perspective View of my improved scaffold. Fig. 2 is a transverse vertical sectional view. Fig. 3 is a detail sectional view ofa portion of the extensible operating shaft; and Fig. t is a detail of an extensible side bar.

Referring to thedrawings a--a designate the end frames of my scaffold'which are composed of the posts a'a', connected by the cross-bars a"a". These cross-bars are socured to both sides of said posts, and form guides for the vertically movable frames 13,1).

.These vertically movable frames are composed of the vertical posts b'-b, whose outer sides bear against the inner sides of the posts of the stationary frames, and the upper horizontal cross-piece b" which is secured to the upper ends of the postsb'bsnitablebraces being provided to hold the vertical posts rigid.

The upper ends of the posts a of the stationary frames are recessed as shown in Fig. 1, to receive the extended ends of the crossbars b -b" of the movable frames when said frames are lowered. The object of this is to protect the ends of the cross-bars of the movable frames-when moving the folded scaffold. This construction also renders the end frames more rigid when the scafiold is folded. The stationary end frames are connected and held in an upright positition by the side bars c-c, said side-bars being removably secured to the end post of the stationary frames for a purpose hereinafter described.

To the outer sides of the posts of the stationary frames, at a suitable point thereon, are secured cross-bars d'd, in the center of which is journaled the extensible operating shaft e. This shaft extends lengthwise of the .scafiold and: is formed of two sections of equal length conneetedby a sleeve 6', the-two sections of the shaft being adjustably held in ,said sleeve by means of two set-screws ff tapped through the sleeve, one set-screw bearing on each section of the shaft. On the shaft 6, and near the inner sides of the cross-bars d are rigidly secured drums g, and to these drums are secured cords or chains h whose other ends are removably secured to the under side of the lower ends of the posts of the movable frames.

The operating shaft is extended beyond the cross-bars d and have squared ends over which may be placed the end of a crank for revolving said shaft.

When the operatingshaft is revolved, the

cords h .will be wound on the drums g-g and the movable frames raised as is evident.

To hold the movable frames in their raised position I provide pins i which are passed through holes in the posts of the stationary frames, and extend into corresponding holes or recesses in the adjacent sides of the posts of the movable frames. A series of these holes is provided in order that the movable frame may be held in its various adjusted po-.

sitions. The pins II are secured to the posts a" by means of cords or chains t" in order that they will always be in position for use, and will not become misplaced.

When it is desired to extend the scaffold in length the side-bars c are removed, and bars of a greater length secured to the posts in their stead; or an extensible bar'shown in Fig. 4: formed of two pieces, slotted at their overlapping ends and adj ustably secured together by a bolt, may be used, and adjusted to correspond to the adjustment of the operating shaft. It will thus be seen'that I provide a scaffold of simple construction which may be adjusted in length and height, and which may be securely locked in its adjusted positions. Another advantage of myimprovement is that my scafiold may be readily taken apart, which facilitates the moving of the scafiold from room to room when it is used in buildings for any of the various purposes requiring scaffoldin Asshown inFig. 2 of the drawings the posts of the stationary frames may be provided at centrally in the stationary frames and means for revolving said shaft, cords or chains secured at one of their ends to said shaft, their other ends being secured to the lower ends of the movable frames, means forsecuring the movable frames in their raised position and extensible side-bars connecting the stationary frames, substantially as described.

- 2. An extensible scaffold consisting of a longitudinally adjustable frame, vertically movable frames supported by said stationary frame, an operating shaft journaled in the stationary frame, said shaft consisting of two sections adjustably connected by a sleeve and set screws, cords secured at one of their ends to the shaft at each end thereof, the other ends of said cords being secured to the lower ends of the posts of the movable frames, removable pins adapted to pass through one of a series of holes in the posts of the stationary frame, their inner ends entering one of a series of holes formed in the posts of the movable frames, and means for revolving the operating shaft, substantiallyas described.

In testimony whereof I alfix my signature in presence of two witnesses,

MONROE KING. Witnesses:

GEORGE A. LAND, EDWARD E. SHARPE.

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