US66585A - haeyey - Google Patents

Description

En vo @eine g; tette gettati @ffice IMPROVMENI IN SGREWAS.

@te tlgthvfle referat tu in these tettert ttmt unt mating putt nf tigt same.

TO ALL WHOM IT MAY CONOERN:

Be it known that I, H. A HARVEY, of the city, county, and State of New York, have invented a new and useful improvement in Wood-Screws and I do hereby declare that-the following is afull, clear, and exact )description thereof', which will enable others skilled in the art to make and use the same, reference lbeing had yte the accompanying drawings, forming part of this specifica-tion. l

The object of this invention is to construct the head of a gimlet-pointed wood-screw of a globular or spherical form, and to provide for driving it without cutting the ordinary nick across its face. And the iuvention consists in boring holes obliquely into the head, the direction of which shall be at about an angle of fortyl'ive degrees with' the shank of the screw, whereby, with a properly constructed' `screw-driver, the screw may be driven without injury to the head. The drawing.-

Figure 1, represents a longitudinal sectional view of a gimlet-pointed screw constructed according to my plan.

Figure 2 is' atop view of the head.

Figure 3 is a longitudinel section of a screw-driver designed for this kind of screw.

Similar letters of reference indicate corresponding parts.

a a represent the holes which are made in the globular head of the screw.

It is well known that although globular-headed screws present a much more neat and handsome appearance than the ordinary fiat-headed screw, they are but little used `from the fact that the nick across the face of the head destroys its otherwise neat appearance, for in order to get a good hold with the common screw-driver, the nick must be very deep, which of course injures its appearance and increases its liability to burst open. These objections are obviated by my method of construction.

The jaws b b yof the screw-driver are springs, and c, in a slide, which, when it is slipped forward, brings the jaws' together sufficiently for the pins d d to enter the holes a a. It will be seen that the screw thus formed can be held, supported, and driven with the greatest facility in all situations. l

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

1. Constructing wood-screws of the globular-head form, with the oblique holes a a in the heads thereof', substantially as shown and described, in combination with the gimlet-pointed screw, as la new article of manufacture.

2. In combination with a screw thus formed, I claim the screw-driver B, constructed substantially as described for the purposes set forth.

. H. A. HARVEY.

Witnesses:

Wn. F. McNAMAnA, ALEX. F. ROBERTS.

Images