IMPROVEMENTS IN SCREW HEADS AND IN DRIVERS OR TOOLS FOR THE SAME
Year: 1875

page_text: LETTERS PATENT to Robert Steers, of No 127, Grosvenor Park,
Camberwell, in the County of Surrey, Gentleman, for the In-
vention of "IMPROVEMENTS IN SCREW HEADS AND IN DRIVERS OR TOOLS
FOR THE SAME
"
Sealed the 6th October 1875, and dated the 12th April 1875.
PROVISIONAL SPECIFICATION left by the said Robert Steers at the
Office of the Commissioners of Patents, with his Petition, on the
12th April 1875.
I, ROBERT STEERS, of No 127, Grosvenor Park, Camberwell, in the
County of Surrey, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SCREW HEADS, AND IN DRIVERS OR TOOLS
FOR THE SAME," to be as follows :-
-
This Invention relates to improvements in screw heads and in drivers
or tools for the same, and consists in forming by stamping or otherwise
a six-sided aperture in or down the central part of the head, three of
which sides are of less or of greater area or width than the other three,

page_text: so that a fair bite of a driver or tool may be had for turning the screw
without fear of the tool shipping from the aperture during the turning to
screw up or to unscrew, as the case may be.
The tool or driver I use for the heads of the screws above mentioned
has corresponding sides, and has preferably a tapering end so that it {
may be available for screw heads of different diameters.
The inner surfaces of the aperture in the screw head may be tapered
or approach a point in the shank or shoulder, so that the strength of
the head at that part is not reduced.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Steers in the Great Seal Patent Office
on the 12th October 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
STEERS, of 127, Grosvenor Park, Camberwell, in the County of
Surrey, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Ier
Letters Patent, bearing date the Twelfth day of April, in the year
of our Lord One thousand cight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Robert Steers, Her special
license that I, the said Robert Steers, my executors, administrators,
and assigns, or such others as I, the said Robert Steers, my exċ-
cutors, administrators, and assigns, should at any time agree with, and
no others, from time to time and at all times thercafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ircland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN SCREW HEADS, AND IN DRIVERS OR TOOLS FOR THE SAME," upon the condition
(amongst others) that I, the said Robert Steers, my executors or admi-
nistrators, by an instrument in writing under my, or their, or one of
their hands and scals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to

page_text: Figure 4 shows a slightly modified form of tapered driver, and
Figure 5, a plan of a screw head with a central recess therein of a form
corresponding to that of the driver. In this modification the narrow
sides of the recess and driver are rounded off in lieu of being left flat, as
in the previously described Figures.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion, that I am aware
that parallel sided recesses of rectangular form sunk into the heads of
scrows in substitution for the ordinary nick have been proposed or
employed in conjunction with correspondingly shaped drivers, and that
screw heads have also been made or proposed with three-sided, acuto
angled, pyramidal recesses terminating in a point and actuated by a
driver of like form thereto, but owing to the defective form and broad
taper of the recess and driver the recess tended to weaken the screw
head by the presence of acute re-entering angles, whilst the driver
having a tendency to slip out of the recess when turned was incapable
of taking a firm bite or hold upon the scrow head, and was morcover
extremely liable to injury by the breaking or wearing away of the sharp
angles and point thereof, and therefore I do not claim such forms of
recesses and drivers for screws as constituting any part of my said In-
vention; but what I consider to be novel and original, and therefore
claim as the Invention secured to me by the hercin-before in part recited
Letters Patent is,―
First. The special form of tapered recess in a screw head, shown in
Figures 1 and 2 of the accompanying Drawings, such recess having six
side walls of broad and narrow widths alternately, and a flat bottom, as
and for the purposes herein-before described.
Secondly. The special form of tool or driver for the above having
six sides of broad and narrow widths, arranged alternately, and a flat
end, as and for the purposes herein-before described and illustrated by
Figuro 3 of my Drawings.
Thirdly. The construction and use of the peculiar tapered screwdriver
made with three broad sides and a flat end, and with the angles formed
by the junctions of the sides rounded off, as herein-before described and
illustrated by Figure 4 of my Drawings.
Fourthly. The special form of tapered recess in a screw head, such

page_text: recess being made with three broad sides and a flat bottom, and with the
angles formed by the junctions of the sides rounded off, as and for
the purpose herein-before described and illustrated by Figure 5 of my
Drawings.
In witness whercof, I, the said Robert Steers, have hereunto set 5
my hand and scal, this Eleventh day of October, in the year of
our Lord One thousand eight hundred and seventy-five.
ROBERT STEERS. (L.S)
Witness,
EDWIN P. ALEXANDER,
Consulting Engineer and Patent Agent,
14, Southampton Buildings,
W.C.