US2399436A - Scaffold construction - Google Patents

Description

April 1 J. H. HENDERSON 2,399,436

SCAFFOLD CONSTRUCTION Filed April 9, 1945 3 Sheets-Sheet l s N fill Inventor April 30, 1946. v J, H. HENDERSON S CAFFOLD CONS TRUCTION 3 Sheets-Sheet 2 Filed April 9, 1945 l/DE S OIV Inventor April 30, 1946.

J. H. HENDERSON SCAFFOLD CONSTRUCTION Filed April 9, 1945 3 Sheets-Sheet 5 QR wN 6,27 5% Hen/056 4;

9 Am a Patented Apr. 30, 1946 UNITED STATES PATENT OFFICE SCAFFOLD CONSTRUCTION Jude H. Henderson, Clearfield, Utah Application April 9, 1945, Serial No. 587,300 7 2 Claims. I (01. 304-45) This invention relates to an improved scaffold construction, and one of the objects of the invention is to provide a plurality of hinged uprights and a suspended supporting member, on which the work platform bar is supported, and means for adjusting the position of the platform bar or cross piece on the suspended supporting member.

Another object of the invention is to provide a scaiiold unit, consisting of a group of three legs hinged at their upper ends to a connecting piece, with a pair of angle members which are sup ported at their upper ends on the connecting piece or plate, and a work bar supporting device which is arranged to slide on the depending angle members, and which is provided with means for positively clamping the device to the angle members, to raise and lower the position of the work bar relative to the floor or ground.

Another object of the invention is to provide a clamping device for the work supporting unit, which utilizes a wedge for producing maximum clamping pressure and a screw for tightening or operating the wedge.

With the above and other objects in view the invention consists in certain new and useful combinations, constructions and arrangements of parts, clearly described in the following specification, and fully illustrated in the drawings, in which:

Fig. 1 is a perspective view, showing two of the improved scafiold units in upright positions supporting a platform work bar.

Fig. 2 is a side elevation of the adjustable work bar support.

Fig. 3 is a horizontal sectional view, taken on line 3-3 of Fig. 2, looking in the direction of the arrows.

Fig. 4 is a vertical sectional view through the work bar holding device.

Fig. 5 is a transverse sectional vew taken on line 5-5 of Fig. 4, looking iri the direction of the arrows.

Fig. 6 is a detail vertical sectional view through an extension leg attachment.

Fig. 7 is a detail view of a chain connecting hook.

Fig. 8 is a detail vertical sectional view, showing the pivot connection of the supporting legs with the top cross piece and also the connection of the depending work supporting bars therewith.

Referring to the accompanying drawings, which illustrate the practical applicaton of my invention, 5 designates a top cross piece, which may be a casting or a steel or metal plate, and Which is provided with bearing lugs 6 and I, to which the upper ends of the legs 8, 9 and Ill are pivotally connected. Each of these legs is constructed of steel angles, and the lower end of each leg is cut diagonally so that it will have the required flush engagement with the floor.

To the top cross piece or plate 5 the upper ends of the steel angles II and I2 are connected, in any suitable manner as by welding. On the steel angles II and I2 a plate I3 is fixed to the lower ends thereof. This plate is equipped with three flexible metal chains I4, I5 and I5 the inner ends of which are pinned to the edges of the plate, or connected through small openings I3a, and the outer portions of the chains are adjustably connected wih steelhooks I'I, I8 and I9, which are mounted on the legs 8, 9 and I0, respectively.

On the suspended steel angles I I and 12 a work or platform bar supporting device 28 is vertically slidable. This device or rest includes the top plate 2|, the bottom plate 22, and side plate 23 and which are welded or otherwise united to the plates 2| and 22. The plates 2I and 22 are formed with openings through which the steel angles II and I2 extend. Between the side plates 23 and 24 the clamping members 25 and 26 are supported by the pivot bolt 21, which extends through the side plates 23 and 24 The outer edge of each clamping member is formed convex and the inner vertical edge thereof is formed straight. A Wedge 28 is arranged to work between the inner edges of the clamping members 25 and 26, and the upper end of the screw 29 is swivelled on this Wedge, while the screw has threaded engagement with the bottom plate 22.

The point of engagement of the wedge with the plates or clamping members 25 and 26 is well below the pivotal connection of the same with the bolt 21, which may be a rivet, and when screw pressure is established against the members 25 and 26, the outer arcuate edges of these members will be forced against the inner faces of the suspended steel angles II and I2, as shown in Figs. 4 and 5. When reverse action is applied by the screw, the wedge will be lowered from pressure engagement with the clamping members, thus permitting the entire work bar rest to be adjusted. When pressure is applied through the screw, the wedge, and the swinging clamping members 25 and 26, the steel angles will be forced against the top and bottom plates of the adjustable rest.

Two assemblies are arranged to support the ends of the platform work bar or beam-30, the ends of which are placed on the plate of the rest 20. By adjusting the screw and wedge operated clamping jaws or members 25 and 26 the vertical positions of the companion bar rests may be raised or lowered.

The spread of the scaffold legs is controlled by means of the adjustment of the chains with the hooks of these legs, By connecting links of the chains to the hooks the legs may be held closer to each other, and by making these connections on the chains; with outer links the legs. may be spread wider-apart, and the elevation of the platform or work bar may be influenced.

In work carried on in rooms or quarters with low ceilings or roofs, it is important that a widev spread of the scaifold legs be made, and in work under high roofs or ceilings, or over head struce ture, it may be useful to secure the legs for maximum elevation.

To increase the length of the legs, each leg may be equipped with a clamp 3|, which is connected by the rivet or screw 32 to the lower end of the leg, This clamp is provided with a passage 33 through which the, extension steel angle 34 extends, anda screw 35- is threaded through the clamp 3| against the extension steel angle 34 to hold the same under pressure against the outer portion 3 la of the clamp, as shown in Fig. 6. It is understood that various changes in the details of construction, their combination and arrangement, may be made, within the scope of the invention, as defined by the claims hereof.

Having described my invention I claim as new:

1. A scafiold consisting of a group of three legs, a plate having hinge connection with the upper ends of the legs, bars connected at their upper ends to the plate and depending therefrom, a rest having a top and bottom plate slidable on the bars, said rest also having side plates, a pair of members. hinged at their upper ends to the side plates, a wedge for forcing said members apart against the bars to clamp the same against the top and bottom plates, and a screw threaded through the bottom plate and having swivel connection, with the wedge.

2.. The construction set forth in claim 1, each of the legs having a hook, and a chain connected at itsinner end to the rest and adapted to en gage each hook, whereby the spread of the legs may be regulated.

J-UDE H. HENDERSON.

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