US1437088A - Steel scaffolding ladder - Google Patents

Description

F. BRANDT. STEEL SCAFFOLDING LADDER. APPLICATION FILED JUNEZB. 1920.

Patented Nov. 28, 1922 Patented Nov. 2%, 1922.

I fur. a.

FOKKO BRANDT, OF KANSAS CITY, KANSAS, ASSIGNOB TO THE BRANDT 5c KRELL ENGINEERING COMPANY, OF. KANSAS CITY, KANSAS, A. CORPORATION OF 7 KANSAS.

STEEL SCAFEOLDING LADDER.

. Application filed June 28,

To'aZZ whom it may concern: I Be it known that I, FOKKO BRANDT, a cit Zen of the Republic of Germany, and resident of Kansas City,- in the county of W} andotte and State of Kansas, have invented a certain new and useful Improvement in Steel Scaffolding Ladders, of which the following is a complete specification.

This invention relates to adjustable-ladder step clamps, and more especially to a ladder construction for towers, derricks and scaffolds, the object being to provide steps and clampswhich can be applied to or removed from a standard or upright of such structures quickly economically, and which, in conjunction with .the standard, constitutes an eflicient and safev ladder step or round. y

A furtherobject is to provide steps and clamps. which can be secured to or removed from the standard by one standing on a lower step, and thus provide for an increase or reduction in the length of the ladder as needed.

A still further object is toprovide a-lad- 'der step which can be secured safely in position at any desired points on a tubular standard of metal.

To these ends the invention consists in certain novel and useful features of construction and combinations of parts as hereinafter described and claimed; and in order that it may be fully understood reference is to be had to the accompanying drawing, in which Figure 1 is a fragmentary edge View of a ladder embodying the invention.

Figure 2 is a similar View with the clamp elements in inclined position preliminary to securing the step firmly against the standard or ren'ioving it therefrom.

Figure 3 is a top view of the construction as shown by Figure 1.

Figure 1 shows a portion of a tower or derrick equipped with a ladder embodying the invention.

Referring to the drawing in detail, 1 indicates the standard shown in this instance in the form of a tubular metal pipe, a plurality of these standards in conjunction with horizontal pipes 2, constituting a scaffold, derrick or tower, as disclosed by Figure 4:. In said figure the standards 1 are preferably in the form of superposed see- 1920. Serial No. 392,383.

jecting lugs 6 which act as guards to prevent ones feet from slipping from the steps in a sidewise direction, and cast or otherwise rigidly formed about the center of each step is a lug 7, which lug ifthe step is to be applied to a metal pipe standard, is formed with a concaved rear face 8, conforming to and adapted to fit against the standard, as

shown most clearly by Figure 3.

A U-shaped clamp v9 terminates at the ends of its arms in upwardly and rearwardly facing hooks 10, and the lower portion of the saddle parts of the clamps constitute a concave internal face 11 conforming approximately to the standard, and merging into an upper inclined face 12 which, when the clamp is in operative position, diverges upwardly with respect to the standard, as indicated most clearly by dotted lines in Figure 1. The upper portion of the saddle parts of the clamp is formed with a rearward projection 13 and mounted therein is a clamping screw 14 which is withdrawn to substantiate a position shown by Figure 2,

when the clamp is to be applied in operative position or removed from such position, as indicated in Figure 2.

In securing a step in position, the same is fitted against the standard with the concave face 8 of the block in direct contact with the standard. The clamp is then fitted astride the standard and tilted so that its inclined face 12 shall engage the standard and its hooks shall underlie and engage the step at opposite sides of the lug 7, as shown by Figure 2. The clamping screw is then turned to advance it and cause it to bear against the standard, this action tending to retilt the clamp and slide the step upwardly on the standard until the block is opposite the clamping screw, by which time the lower or vertical face 11 of the clamp is approximately parallel with and engaging the standard, and the ends of the hook are overard.

Assuming that the clamping screw is properly adjusted, it will be obvious that it is impossible for the step to shift its position in any direction, and hence it constitutes a safe and strong support for a person ascending or descending the ladder, as any increase in load upon the step tends to cause the lug to clamp more firmly against the standard because the relation of the parts is such that the clamp and step can not slide downward without first effecting tilting action of the former. It is also obvious that as the arms of the clamp fit snugly against opposite sides of the standard no lateral shifting of the latter can occur.

I claim:

1. In a ladder, a standard, a step fitted against the standard, a clamp engaging the standard at the opposite side thereof from said step, and a clamping screw mounted in the clamp and engaging the standard and tending to tilt the clamp to cause the same to'press forwardly against the standard and rearwardly against the step to clamp the latter firmly against the standard.

2. In a ladder, a standard, a step fitted against the standard, a U-shaped clamp engaging the rear face of and projecting forwardly at the side of the standard and terminating in upwardly and rearwardly facing hooks engaging the step, and means tending to tilt the clamp to cause the same to press against the standard in a forward direction and the step to press against the standard in a rearward direction.

3. In a ladder, astandard, a step fitted nae-rose against the front side of the standard, a if shaped clamp fitting astride the standard and terminating at the front ends of its arms in hooks underlying and engaging the front and upper sides of the step; said clamp comprising a lower Vertical portion and an upper inclined portion, and a clamping screw extending through the inclined portion and engaging the standard and tending to tilt the clamp to clamp the lower portion thereof against the standard and cause the hooks thereof to clamp the step against the standard.

4:. In a ladder, a standard, a step fitted against the front side of the standard, a U-shaped clamp fitting astride the standard and terminating at the front end of its arms in hooks underlying and engaging the front and upper sides of the step; said clamp comprising a lower vertical portion and. an upper inclined portion, and a clamping screw extending through the inclined portion and engaging the standard and tending to tilt the clamp to clamp the lower portion thereof against the standard and cause the hooks thereof to clamp the step against the standard; said step terminating at its ends in upwardly projecting lugs.

5. In a ladder, a standard, a member fitted against the standard and forming a step, clamp engaging the step member, and a clamping element mounted in the clamp and engaging the standard and tending to cause relative tilting movement of the step member and clamp to clamp them in position on said standard.

In testimony whereof I hereunto aflix my signature.

FOKKO BRANDT.

Images