An Improved Screw-nail.
Year: 1894

page_text: Date of Application, 22nd May, 1894-Accepted 30th June, 1894
An Improved Screw-nail.
I, CHARLES JAMES POLAIN, of "The Olderfleet" 475 Collins Street,
Melbourne, in the Colony of Victoria, Australia, Patent Agent, do hereby declare
"and in what
the nature of my invention for "AN IMPROVED SCREW-NAIL
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :—
The object of my invention is to provide a screwnail with the advantages of a .
nail needing no boring, combined with the facilities and advantages of being
withdrawn as a screw. The saving trouble of carrying the tools necessarily in the
turning screws also the avoidance of destruction usually attending the withdrawing
of common nails,
Screws (ordinary) although intended to be prepared for by boring and screwed
in are invariably driven in thereby destroying the fibres of wood in the whole
circumference. This in a great measure applies to the securing of corrugated iron
for roofing.
It is proposed that the screwnail be made of either square polygonal or
triangular iron or other metal with threads stamped cut or wrought on edges only;
leaving 4 or 3 or more plain faces respectively representing in reality in one case as
if you filed 4 flat sides on a common screw at right angles leaving threads on each
edge uninterfered with.
But in order that my invention may be better understood, I will now refer to the
accompanying drawings.
Figure 1 is an elevation of a screw-nail as prepared from square wire. A is its
shank A the part thread wrought on angles of same to a helical plane. The
screwnail is provided with a circular collar A³ so as to admit of the turning of
screwnail without damage to the material; and is mounted with a square head.
A³ is a head square in shape so as to admit where practicable of being withdrawn
by the claw of a common hammer, pinchers or like tools.
A' is a stopped slot cut in head for facility in withdrawing, or tightening by an
ordinary screw-driver, when the screwnail is forced in beyond the reach of a
"hammer claw."
The position of slot being diagonal and stopped at ends gives additional strength
than if placed at right angles.
It is advantageous that the screwnail be driven home within one fourth turn of a
screwdriver, which will ensure additional hold by the position of projecting thread
5 as before referred to.
Figure 2 is a plan of head as referred to in Figure 1, and exhibits A" the circular
collar, A³ a head surmounting same, and A* the stopped slot.
Figure 3 is an end view of screw.
Figures 4 & 5 respectively show a design of a head which I intend to adopt for
O use in securing corrugated iron, or similar heavy work A' is a collar, formed upon
said shank A, A³ a square head, A* the stopped slot. As a detachable bead washer
preferably shaped with concave one way so that when driven firm it will close over
the corrugation.
Figures 6, 7, 8 & 9 with their relative letters of reference are illustrations of
5 the ordinary heads, which I may adopt in combination with my screw nail,
according to circumstances.
Figure 10 is a section of a screwnail wrought out of triangular wire. A is the
chonk and Al the part threads.

page_text: Figure 11 is a section representing the manner of applying a wire of polygonal
shape.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what 1
claim is
The screwnail formed of iron or other metal triangular, square, or polygonal in
section with the edges or angles having part screw thread stamped cut or wrought
thereon. The same nail being provided with solid collar or separate washer and
having a square head with diagonal slot.
Dated Oth day of A l 100
W. D. ROWLINGSON,
Agent for Applicant.