US87389A - Improved scaffold - Google Patents

Description

ILPETERS, PHOTOYLITHDGRAPHER, WASHINGTON. D. C.

Massara-W- FREDERlCK APP, 'OF

TO HIMSELFAND SELlNS GROVE, PENNSYLVANIA;A SSIGNOR J. S. BURKHART, OF THE SAME.- PLACE.

Leners Patent No. 87,389, aan March 2, 1869.

To all whom 'it may concern:

Be it known that I, Fnnnneicx APP, of Selins Grove, in the county of Snyder, and State of I` enn Sylvania, have invented a new and useful Improvement in Scaffolds ;v and I do hereby declare that the following is a full, clear,

and exact description thereof, which will enable others skilled in the art to make and Ause the same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure `1 is a side elevation of my improved scaffold.

Figure 2 is an end elevation of the same.

Similar letters of reference indicate .like parts.`

The object of this invention is to vprovide a scaffold for house-painters and other persons employed in work ing on the-walls of buildings.

It consists, in general terms,of scaEolds, or platforms, arranged to raise agd lower between two pairs of uprights forming -the corner-posts of a frame, and

provided with a winch or crank-windlass, and its accessory ropes and pulleys, arranged in such a manner, that a'person or persons on the scaffold can raise or lower the same without leaving it.

In the drawings- I A are the corner-posts of the frame. These rise from the bed-frame B, and are surmounted by' crosstimbers, C, 'to the upper sides, of which arealixed the sheave-blocks D.

E is a movable scalold, arranged between the posts A, in the manner shown'. A

The scaffold bears a winch, or hand-windlass, G, having bearings in a suitable frame, H, affixed to the scaffold, as shown.

.There is a sheave, or grooved pulley, arranged in the frame H, and another one in a similar frame, I, at the opposite end of the platform. v

lhere are three sheaves-in one of the blocks D, and two in the other, and the rope working in the several sheaves is rove or arranged in the following manner:

One end of the-rope is tied to some part of the platform, as the hook a.' It then passes over 'one of the sheaves in the blockD, then down and under the sheave in the frame I, thence up and over the second sheave in the first block D, and passes from that to the irst sheave in the block D at the other end of the frame. It then descends to the winch-drum, and, passing through it, ascends again to the third sheave in the block. Thence assinc down and underthe sheave in the frame H and p C' 7 up and over the middlesheave of the block, and from thence down to a second hook, b.

The red arrows indicate the direction in which the several parts move `when the scaffold is being raised.

In order to hold the scaffold at different heights, I employ two cross-bars, J J, suspended below `the scaffold by rods d, connectingthe said cross-bars with the guidebars e, ahxed. to the upper side of the scaifold, asshown.

ifIhe rods d are attached loosely tothe guide-bars', so

as to allow the cross-bars to swing clear of the rest-plate v K, when the platform is being raised.

Springs, M, attached to the cross-bars and scalfold,

, as shown, act to draw the former toward the posts aftenpassing the rest-plates K, which latter have oblique edges, as shown, to bear oli` the cross-bars when the scaiiold rises.

L are guard-plates, pivoted to the posts, in such relation to the rest-plates, that they will rest upon the said rest-plates in the manner shown, ,thus presenting curved or oblique edges, which operate to bear oli the cross-bars of the scaffold, when the latter is descending from above the said guard-plates.

The object of this contrivance is to enable the scaffold to be lodged on the rest-plates, or lowered past them to any point below, without handling the said contrivances, for it will be seen that when the cross-bars are supported by the rest-plates, the guard-plates are lifted therefrom and rest on the cross-bars, but when the cross-bars lise clear ofthe guard-plates, the latter fall again in contact with the rest-plates and present obliqe or curved edges, which guard or bear olf the descending cross-bars, and thus prevent them from lodging on the rest-plates.

The lower corners ofthe guard-plates project slightly beyond the ends of the rest-plates, so that the crossbars will encounter the guard-plates when the scaffold is ascending.

Pairs of rest and guard-plates are arranged at suitable intervals along the posts.

In order to lower the scaffold to any of the lower Y rest-plates,`it is first raised, to clear it ofthe guardplates then resting on the cross-bars, which plates will fall upon the rest-plates, as before described, and cnaf ble the cross-bars to pass down. rIhe cross-bars must be lowered past the rest-plates, where they are designed to be lodged, and again raised, to bring the said bars underthe guard-plates of the new position.

These contrivances enable the scaffold to be held at any point, in a stable and secure manner, by simply turning the winch, and are far superior to the ratchetrack and catches heretofore employed in like situations.

O O are diagonal braces ofthe frame.

P is a step-ladder for ascending to the platform.

By the arrangement of the rope and pulleys Ainthe manner set forth, the scaiold is made to raise or lower parallel to itself, and afford'the means for painters or others working on the walls of buildings, to work from the top of the wall downward, or from the bottom upward, as may be desired, without the usual delay in shifting the scaffold.

The springs M may be substituted by cords and weights, as will be obvious.

Having thus described my invention,

I claim as new, and desire to secure by Letters Patent- 1. The arrangement of the Winch G, platforms H and I, and-the rope and pulleys, with reference to the frarne the movable cross-bars J of the sealold, and spring M, and the platform E, lwhereby the centre of said platform (or its equivalent all as and for the purpose set forth. is left unobstructed, both ends being raised and lowered FREDERICK APP. simultaneously by the wmeh Gr, outside of one of the upright-s, es herein shown and described. Wlmesses:

2. The rest-plates K and guard-plates L, arranged, A. B. HEISTANI, on the frame-posts A, as described, in combination with JONTH. FISHER.

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