US1100777A - Scaffold. - Google Patents

Description

UNITED STATES PATENT OFFICE.

SAMUEL RASHKOVSKY, OF ST. LOUIS, MISSOURI.

SGAFFOLD.

To all whom it may concern:

Be it known that I, SAMUEL RAsnKovsKY, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Scaifolds, of which the following is a full, clear, and exact description, such as will enable-others skilled in the art to which it appertains to make and use the same.

This invention relates to scaffolds such as are erected on the outside of a building to form a supporting platform for workmen who are engaged in work on the exterior of the building.

One object of my invention is to provide an adjustable scaffold in which the vertically-disposed member or members that sustain the platform or staging are each made up of a plurality of rack-toothed bars that are connected together in a novel manner.

Another object is to provide a strong and substantial adjustable scaffold that can be changed easily for use on high or low buildings, and which can be stored compactly when it is not in use. And still another object is to provide a safe scaffold which is so designed that the platform or staging can be raised and lowered easily and locked securely in adjusted position by the workmen on the platform.

Other objects and desirable features of my invention will be hereinafter pointed out.

Figure 1 of the drawings is a side elevational view of an adjustable scaffold constructed in accordance with my invention; Fig. 2 is a front elevational view of one of the vertically-disposed sectional tracks and the adjustable carriage on same which supports one end of the platform or staging; Fig. 3 is a detail horizontal sectional view taken on the line 3-8 of Fig. 2; and Fig. 4 is a detail horizontal sectional view taken on the line l-4 of Fig. 1.

Referring to the drawings which illustrate the preferred form of my invention, A designates a plurality of rack-toothed bars that are connected together so as to form a vertically-disposed track which is suspended in some suitable manner from the roof or cornice of the building, as, for example, by means of hooks 1. I have herein shown only one of said tracks and the traveling carriage on said track that supports the staging or platform; but it will of course be understood, that, in practice, two of said tracks and carriages are used whenever a compara:

Specification of Letters Patent.

Application filed March 1, 1913.

Patented June 23, 1914. Serial No. 751,439.

tively long staging or platform is provided for the workmen to stand on. The racktoo-thed bars or members A preferably consist of thin strips of steel provided on one edge with teeth 2 and having their ends joined together by means of C-links 3 that pass through holes in said bars and which are disposed at approximately right angles to the bars so that they project laterally from the sides of same, as shown clearly in Fig. 1, thus forming a long sectional track on which the platform-sustaining carriage travels. The links 3 are preferably provided with openings, as shown in Fig. 1, so as to permit the bars and links to be connected and disconnected easily. The platform-sustaining carriage herein shown is composed of two angle bars 1 that are tied together by transversely-disposed braces which are so designed that they act as guides for the vertically-disposed track on which the carriage travels. The brace or tie member at the upper ends of the bars 4 preferably consists of a casting 5 in which a pinion 6 is journaled, as shown in Figs. 2 and 3, so as to mesh with the teeth 2 on the rack-bars A and thus cause the carriage to move vertically on the track when the pinion 6 is rotated, said pinion being provided with a crank arm or handle 7 that can be actuated by a workman standing on the platform or staging B, indicated. by broken lines in Figs. 1 and 2. The tie member 5 is provided with a guiding portion 8 through which the racktoothed bars A pass, and said guiding portion 8 is so formed that the C-links 3 that connect the rack-bars A together can travel through same, the guiding portion 8 of the casting 5 at the upper end of the carriage being provided at one side with a slot 8 and at its opposite side with a recess 8 which is arranged diametrically opposite the slot 8 as shown in Fig. 3. The transversely-disposed brace or tie member 9 that is connected to the angle bars 1 intermediate the ends of same, is provided with a similar guiding portion 9 for the rack-toothed bars A and C-links 3, and the lower ends of the angle-bars 4 are tied together by a transversly-disposed brace or tie member 10 of similar construction to the members 5 and 9 previously described, the tie member 10 being shown clearly in Fig. 4E.

The vertically-disposed track and the carriage that travels thereon are held away from the side of the building by means of a brace C at the lower end of the carriage which is provided with one or more rollers 11 that bear against the outer face of the Wall of the building, as shown in Figs. 1 and at. The brace C herein shown is adjustably connected to the platform-sustaining carriage, and preferably consists of a bar, bent to form two side legs 01' portions 12 that embrace the tie member 10 at the lower end of the carriage, said tie member 10 being preferably provided with guides 10 through which the side legs 12 of the brace O pass. Any suitable means may be employed for securing the brace C to the carriage, the means herein shown consisting of wing-bolts 18 on the guides 10 that pass through holes 14 in the side legs 12 of the brace. As shown in Figs. 1 and a the side legs of the brace C have a plurality of holes 14 so as to provide for the lateral adjustment of said brace, and said side legs 12 are made long enough so that they will project a sufiicient distance beyond the opposite side of the carriage to form a substantial support for the staging or platform B on which the workmen stand.

Means is provided for locking the carriage in adjusted position, and in the embodiment of my invention herein shown said means consists of a dog 15 pivotally connected to the intermediate tie member 9 on the carriage and provided with a tooth 15"* that cooperates with the teeth of the rack-bars A. A leaf-spring 16 that is connected to the carriage tends to force said locking dog into engagement with the rackbars, and a catch 17 is provided for holding said locking dog either in an operative or inoperative position, the catch 17 being pivotally mounted on a bracket 18 on the carriage and adapted to cooperate with one of a pair of notches 19 in a laterally projecting arm on the locking dog 15, as shown in Fig. 2.

l/Vhen it is desired to raise or lower the platform B on which the workmen are standing the workmen move the locking dogs 15 of both carriages into an inoperative position and then rotate the pinions 6 on said carriages in the proper direction, the rotary movement of said pinions causing the carriages to move vertically with relation to the rack-toothed bars A that form the tracks for the carriages. The bars A can be connected together easily so as to lengthen or shorten the tracks, and when the scaffold is not in use it can be stored in a small space owing to the compactness of the carriage and of the flat bars A that form the track.

Such a scaffold can be modified easily so as to enable it to be used on either a high or a low building; the supporting platform B on which the'workmen rest can be adjusted toward or away from the wall of the building by simply changing the adjustment of the brace C; the scaffold is perfectly safe and is capable of supporting a great load, and on account of its simple construction it can be manufactured and marketed at a low cost.

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

1. In a scaffold, a vertically disposed track suspended from a sustaining member and made up of a plurality of flat metal bars having rack teeth formed on one edge of same, substantially C-shaped links for connecting said bars together, said links being disposed at approximately right angles to said bars and having openings which permit the bars and links to be connected and disconnected easily, a carriage arranged to travel vertically on said track and provided with guides which emb ace the opposite sides of the track, said guides having openings or spaces so as to provide a clearance for the links that connect the bars together, a manually-operated pinion 011 said carriage that meshes with the rack teeth on said track bars and thus causes the carriage to travel vertically when the pinion is rotated, and means on said carriage for sustaining a platform and for holding the carriage and track spaced away from the wall of the building on which the scaffold is used.

2. In a scaffold, a vertically disposed track suspended from a sustaining member and made up of a plurality of flat metal bars having rack teeth formed on one edge of the same, substantially C-shaped links for connecting said bars together, said links being disposed at approximately right angles to said bars and having openings which permit the bars and links to be connected and disconnected easily, a carriage arranged to travel vertically on said track and provided with guides which embrace the opposite sides of the track, said guides having openings or spaces so as to provide a clearance for the links that connect the bars together, a manually-operated pinion on said carriage that meshes with the rack teeth on said track bars and thus causes the carriage to travel vertically when the pinion is rotated, means on said carriage for sustaining a platform and for holding the carriage and track spaced away from the wall of the building on which the scaffold is used, means on the carriage for locking the carriage to the track, and means for enabling the carriage and track to be adjusted toward and away from the wall of the building.

3. In a scaffold, a relatively long and narrow vertically-disposed carriage provided on one side with guides, a vertically disposed track passing through said guides and having its upper ends suspended from a sustaining member, said track being made up of a plurality of flat strips of metal joined together by links that are disposed at right angles to the strips, rack teeth formed in one edge of said strips, a housing on the guide at the upper end of the carriage, a manually-operated pinion journaled in said housing and meshing with the teeth on the strips that constitute the track, and a wallengaging brace at the lower end of the carriage provided with an outwardly projecting portion for sustaining a platform.

4. In a scaffold, a relatively long and narrow vertically disposed carriage which is substantially channel-shaped in cross section, guides extending transversely of the web of said carriage, a vertically disposed track passing through said guides and having its upper ends suspended from a sustaining member, said track being made up of a plurality of flat metal bars arranged parallel to the web of the carriage and detachably connected together by substantially C- shaped links disposed at right angles to the bars, the guides on the carriage being so shaped that said links can pass through same easily, a pinion on said carriage that meshes with rack teeth formed in the edges of said track bars, a locking device on the carriage that cooperates with said rack teeth to hold the carriage in adjusted position, a wall brace at the lower end of the carriage that embraces same and projects forwardly from the carriage so as to sustain the platform of the scaffold, guides on the carriage through which the side portions of said wall brace pass, and means for adjustably-connecting said wall brace to the carriage.

In testimony whereof I hereunto affix my signature in the presence of two witnesses, this twenty fifth day of February 1913.

SAMUEL RASHKOVSKY.

.lVitnesses WELLS L. CHURCH, GEORGE BAKEWELL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of I'atents. Washington, D. G.

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