US2219971A - Scaffolding jack - Google Patents

Description

Oct. 29, 1940. ALLARD 2,219,971

- SCAFFOLDINGIJACK Filed July 6, 1939 2 Sheets-Sheet 1 I b I f )6 Inventor HE. MY/hard B9 Magma 5% A tiorneys Oct.- 29, 1940. 5 ALLARD 2,219,971

' SCAFFOLDING JACK Filed July 6, l939 2 Sheets-Sheet 2 Inventor Patented Oct. 29, 1940 UNITED STATES PATENT OFFICE SCAFFOLDING JACK Hugh E. Allard, Matfield Green, Kans.

Application July 6, 1939, Serial No. 283,091

1 Claim.

This invention relates to scaffolding jacks, and has for the primary object the provision of a device of this character which will permit a scaffold to be easily and quickly secured on a shingled 5 roof without the use of nails and like fasteners and which may be conveniently shifted from one place on the roof to another place and when applied will be prevented from accidentally shifting its position thereby assuring against freeing of 10 the scaffold when the latter is supporting persons engaged in work on the roof.

With these and other objects in view, the invention consists in certain novel features of construction, combination and arrangement of parts 16 to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawings, in which 20 Figure 1 is a top plan view illustrating a scaffold jack constructed in accordance with my invention and showing the same applied to a fragmentary portion of a shingled roof.

Figure 2 is a sectional view taken on the line 25 2-2 of Figure 1.

Figure 3 is an end view showing the device when removed from the roof.

Figure 4 is a bottom plan view illustrating the device.

Figure 5 is a detail sectional view showing one of the calks or tines of the device.

Referring in detail to the drawings, the numeral 5 indicates a base plate of substantially rectangular shape and has one end beveled, as

5 shoWn at 6, to faciltate the insertion of the base plate under shingles l at a roof 8.

The base plate adjacent one end has struck therefrom an ear 9 which extends at right angles to the top face of the base plate and when the 40 device is in use is adapted to extend vertically between adjacent edges of shingles so as to prevent the base plate from shifting sideways on the roof.

A lever 10 has one end thereof pivotally and 45 detachably connected to the ear 9 andits opposite end terminates in a hook-shaped portion II to receive and support a part of a scaffold of a conventional construction. The length of the lever I0 is such that it will project a distance 5() beyond one end of the base plate, as clearly shown in Figure 2, and has formed on opposite-edges thereof arms I 2 lying in the same plane with the lever. Calks l3 are carried by the arms [2 and during the use of the device are adapted to bite 5 into the shingles between which the ear 9 extends. The calks I3 biting into the shingles will prevent the base plate from sliding endwise on the roof.

The calks are constructed as shown in Figure 5, that is, each includes a pointed portion l5, a 5 screw threaded shank l6 integral therewith and a screw type head H, the latter being countersunk in the arm. This construction permits the calks to be readily removed when necessary for repair or replacement. The base plate directly 10 under the arms 12 is provided with openings l8 to receive the pointed portions l5 of the calks when the device is not in use, and into which the caulks may be fitted when in use to anchor said plate and lever together against relative twisting 16 edgewise under sudden twisting strains imposed sidewise against said lever.

It is to be understood that after the base plate has been properly applied to the roof, the lever I0 is brought into engagement with the shingles 20 and if desired may be struck a blow for the purpose of drivin the calks into the shingles thereby firmly anchoring the lever to the shingles which in turn prevents the base plate from sliding endwise on the roof and the ear 9 prevents the base plate, by being positioned between a pair of singles, from shifting sidewise.

Thus it will be seen that a very efficient, durable and compact jack has been provided which can be easily and quickly adapted to a shingled roof for the purpose of supporting a scaffold and may be conveniently adjusted from one place to another on the roof. Further, it is to be understood that this device will be utilized in sets for the support of the scaffold on the roof and can be manufactured and sold at a low cost.

It is believed that the foregoing description, when taken in connection with the drawings, will fully set forth the construction and advantages of this invention to those skilled in the art to 0 which such a device relates, so that further detailed description will not be required.

Having thus described my invention, what I claim is:

A scaffold jack for use on a shingle roof comprising an elongated base plate for insertion one end foremost under a pair of side by side shingles, an ear upstanding from said plate to extend upwardly between said pair of shingles, a lever pivoted at one end on said ear for vertical swinging movement above said plate and shingles in the longitudinal center of the plate and having an upturned terminal hook at its opposite end for supporting a scaffold bar, whereby said lever is depressed toward said shingles under the weight of said bar, and means on said lever for anchoring the same to said shingles under such depression thereof, said means comprising a pair of arms extending laterally from opposite sides of said lever, and a pair of caulks on the outer ends of said arms, respectively, for biting into said shingles, said base plate having apertures therein for the passage of said caulks therethrough, and said caulks being tapered to fit in said apertures and anchor the base plate and. lever together against relative twisting edgewise. t

HUGH E. ALLARD.

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