US530682A - Adjustable bracket-scaffold - Google Patents

Description

(No Model.)-

B, 0. DAVIS. ADJUSTABLE JBRAGKET'SGAFFOLD.

No. 530,682. Paien ted Dec. 11, 1394.

NITED STATES PATENT OFFICE.

REES OQDAVIS, OF SAN FRANCISCO, CALIFORNIA.

ADJUSTABLE BRACKET-SCAFFOLD.

SPECIFICATION forming part of Letters Patent No. 530,682, dated December 11, 1894.

Application filed March 16, 1894- Serial No. 503,935. (No model.)

To all whom it may concern.-

Be itknown that I, REES O. DAVIS, a citizen 4 of the United States, residing in the city and county of San Francisco, State ofOalifornia,

. floor of the scafiolding, the outer ends of the frame-work being suspended by pulley-blocks and ropes whereby the scaffolding may be raised or lowered at will, and in conjunction therewith of braces attached and arranged with relation to the scaifold, so that it will be held in contact with the side of the building and retained in a level and firm position without other attachment.

Referring to the accompanying drawings for a more complete explanation of my invention,-Figure 1 is a side view of my invention, showing its construction. Figs. 2 and 3 are end views of thesame.

A A are the end timbers or frames of the scaffolding, each being composed of two parallel timbers, suitably bolted together and having clamped and secured between them, the ends of the brace bars or timbers B. These bars B are firmly fixed between the outer ends of the timbers A and extend downwardly and inwardly at such an inclination that the lower ends come in contact with the side of the building and are beveled 01f so as to stand parallel therewith. The bars B are each composed of two pieces which lie close together where they are fastened between the timbers A. Just below this they are separated by means of an interposed wedge or plug 0 and stand sufliciently far apart to allow the bar D to pass between them, and be adjustably secured. The upper end of this bar D is pivoted between the inner ends of the timbers A as shown at D, and the lower end has journaled in it a pulley E fora purpose to be hereinafter specified.

Between the lower ends of the barsB are journaled rollers F which project slightly from the beveled ends of the bars B lying in these rollers thus projecting, travel against the building when the scaifolding is raised or lowered, and thus relieve the friction which would otherwise be caused by the rubbing, of these parts. The bars B are also supported by braces G which connect the inner ends of the timbers A with the bars B at a point near their lower ends. 1

Upon the top of the timbers A, the horizontal floor planks H H are fixed by bolts,'or otherwise, secured to the timbers ateach end. To the outer ends of the timbers A are fixed the pulley'block's I, and corresponding blocks J are suspended from a projecting beam or timber K which is either fixed to the upper plates or walls of the building, or if the roof is in'place, these timbers may be-fixed upon the roof so-as to project a proper distance beyond its edge.

By means of the rope L passing around the sheavesin the pulley blocks, the outer ends of the timbers A are suspended, and the rope, after passing around the pulley blocks, passes down between the timbers A and around a pulley M which is journaled at that point, and

thence it passes outwardlyaround the pulley E in the end of the bar D. Thence the rope is carried down to a suitable point N either near the ground, or window, or opening, or other suitable point, where it is fastened. The action of this rope, forming an angle as it does between the points M, E and 'N, is to force the inner ends of the timbers A, and the lower ends of the braces B against the side of the building, thus forming a base of considerable length which supports the platform of the scaifolding in a. level and firm position, preventing it from swinging out away from the building,or in other ways being unsteady. The angle atE is changed to suit conditions, by moving the bar D around its pivot point D so as to slide it up or down between the bars B. It is fixed at any desired point bya pin or pins passing through one of the holes 0 made in the bars B and the corresponding hole in the bar D, the pin locking them at either point where it is passed through them. These movements of the barD will throwthe end E farther out or nearer to the building, as may be desired, and thus regulate the pressure which is applied to hold the scaffold in place.

On the inner ends of the timbers A are antifriction rollers P which are adapted to travel against the side of the building in the same manner as described for the rollers F which are journaled in the ends of the bars B.

The rollers P and F are sufiiciently far apart so that one of them will always rest upon the smooth surface of the building front if the other is passing over some irregularity, such as rustic, with which ordinary wooden buildings are often covered, and which has horizontal channels of considerable width at the joints where the rustic overlaps.

It will be manifest that the platform A may be raised or lowered by means of the rope L and the pulley blocks, and in moving it up or down, the rollers F and P will travel in contact with the front of the building and relieve the parts of friction, and when the rope is secured at N the scafiolding will always be firmly held in place.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. A scafiolding consisting of timbers projecting away from the front of the building having a platform secured thereon, brace bars B fixed to the outer ends of the timbers, extending downwardly and inwardly to form contact with the building front, other bars D having their upper ends attached to the in ner ends of the timbers A and crossing the timbers B, pulley blocks and hoisting ropes passing around said blocks, thence around the outer ends of the bars D to a point of attachment upon the building front below the horizontal plane of the brace bars and scaffolding as described.

2. An adjustable bracket scalfold consisting of horizontal timbers projecting away from the building front and having the platform secured thereto, brace bars having their outer ends fixed to the outer ends of the scaffold timbers, and the lower ends in contact with the building front at a point below the scaffolding, other bars having their upper ends pivoted to the inner ends of the scaffold timbers, and the outer ends projecting downwardly and outwardly beyond and below the front of the scafiold, devices by which these brace bars are adjustably united together where they cross each other, pulley blocks at tached respectively to suspending timbers above and to the outer edge of the scafiold timbers, and a rope passing around said pulley blocks, thence around a pulley in the outer end of timbers A and the lower ends of the depending brace timbers D, and thence to a point of fastening upon the building front below the scaifolding as described.

3. The suspended scafiolding with the ropes and pulley blocks, diagonal braces attached respectively to the outer and inner ends of the scaffold timbers crossing and adj ustably united with each other, anti-friction rollers in the inner ends of the scaffold timbers, and the diagonal braces which incline inwardly from their outer ends, whereby the friction of said contact ends with the building wall is relieved, and a pulley in thelower outer end of the diagonal bars D over which the pulley rope passes after leaving the scaffolding, and a fastening for the end of said rope below and interior to said pulley, substantially as described.

t. A scaffolding consisting of a frame work, pulleys and ropes passing around the pulleys whereby the scaffolding is suspended and adjusted, bars secured to the frame work and extending downwardly to form contact with the building front, other bars secured at one end and crossing the first named'bars, and adj ustably connected to the latter at the point of crossing, said second arm projecting beyond the edges of the scafiolding, and over which projecting arms the ropes are passed from the lower part of the scafiolding, and attachments for the ropes interior to the vertical plane of the suspension of the scafifold, whereby the rope acts to retain the scaffold against the side of the building.

In witness whereof I have hereunto set my hand.

REES O. DAVIS.

Witnesses:

S. H. NOURSE, H. F. ASCHECK.

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