Improvements in Screws and Tools for Inserting same.
Year: 1891

page_text: Date of Application, 13th Juno, 1891
Complete Specification Left, 18th July, 1891-Accepted, 22nd Aug. 1891
PROVISIONAL SPECIFICATION.
Improvements in Screws and Tools for Inserting same.
I, WILLIAM RUNDELL of Lanescott Par Station Cornwall Joiner, do hereby
declare the nature of this invention to be as follows:-
The object of this invention is to form a screw that shall be invisible when
inserted.
For this purpose I construct my screws double, that is with a screw thread cut on
each end, & the head in any required position in its length but preferably in the
centre. The screws may be constructed with either left or right hand threads as
required. The heads are formed in various shapes and of dimensions most suitable
for the purposes for which they are used, they may also be bevelled on one or both
sides.
For the insertion of the smaller types of screws the usual slots or cuts are formed
on one or both sides of the head, and they are turned by means of a screw driver of
the usual shape, but having a slot of any required dimensions cut up into the length
of its blade forming two prongs, between which the upper end of the screw extends
while the lower end is being turned into its position.
For the larger types of screws, a square may be formed on each side of the head,
& the screw turned in by means of a hollow square hole centre bit in a brace.
Where it is found necessary to drive one end of the screw into a rod or bar of wood
or other material, the second end of the screw may be driven in by turning the rod
of wood itself by means of a brace formed of two handles of suitable dimensions and
material hinged at one end and having bevelled apertures cut in any part of their
length in which wood or other blocks are fitted their inner surfaces being formed so
that they shall give a good grip without damaging the surface of the material held.
These blocks may be made interchangeable to fit various shapes.
The screws may be made in any suitable metal or of wood, & when inserted &
screwed home on both sides are invisible.
Dated this 13th day of June 1891
GRAHAM & GRAHAM,
Agents for Applicant.
COMPLETE SPECIFICATION.
Improvements in Screws and Tools for Inserting same.
I, WILLIAM RUNDELL of Lanescott Par Station Cornwall, Joiner, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
The object of this invention is to form screws that shall be invisible when inserted,
specially useful in all descriptions of cabinet work.
The
For this purpose I construct my screws of either metal or wood, and of any
dimensions and with either right or left hand threads as required. The head of the
screw may be formed in any position in the length of the screw, but preferably in
the centre and threads are cut on each end thus forming a double screw.
threads of the two ends may be of the same, or of varying pitches, but must both be
either right or left hand threads. The head may be formed of any size and shape
as required for the purpose for which it is to be used, and may be bevelled on either
one or both sides.
On the heads of the lighter types of screws slots are cut on either one or both
[Pmce d

page_text: sides for driving them into position, this is done by the aid of a screw driver of some-
what the usual form with the exception that it has a slot of any suitable length and
width cut up into the length of its blade forming two prongs between which the
upper end of the screw extends while the lower end is being driven into position.
On the larger and heavier types of screws requiring more power to drive them I
form a square on either one or both sides of the head, and drive the screws into
position preferably by means of a hollow square hole bit fitted in a brace, but they
may be inserted by other means if found more convenient. Where one end of the
screw is driven into a bar or rod of wood or other material it may be convenient to
drive the second end of the screw into position by turning the rod or bar itself, for
this purpose I construct a brace formed of two parallel handles hinged or pivotted
at one end and having bevelled apertures cut in any part of their length, such
apertures being opposite to each other.
In these apertures wood or other blocks are fitted of any dimensions, the opposing
faces of which are formed to give a good grip without damaging the surfaces to
which they are applied. These blocks should be made interchangeable and of
various shapes as required. When my screws are driven home on both sides they
are quite invisible and the heads being counter sunk in one or both surfaces of the
material held together gives them a firmer grip and great sustaining power.
For the better illustration of this my invention, I have hereunto annexed a sheet
of drawings in which,
Figs. 1 & 2 are two forms of the lighter screws showing the head C, bevelled or
tapered on one side in Fig. 1 and on both sides in Fig. 2, slots for driving the same
being marked A in both figures.
Fig. 3 is one of the heavier screws with the squares B B formed on each side of
the head C on which the hollow square hole bit Fig. 5 fits, this figure is shown in
section to illustrate the hollow form of the bit at D in which one end of the screw
extends to allow the end of the bit to fit on the square B (Fig. 3).
Fig. 4 shows the form of brace suitable for turning a rod or bar in which, one
end of the screw is already inserted. The rod is held between the two blocks E E
by pressure on the two handles or levere F F hinged or otherwise pivotted as
shown at G.
Fig. 6 shows a portion of the blade of a screw driver adapted for the insertion of
the screws, the upper end of the screw projecting in the slot H between the prongs
or blades I, I.
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 I
claim is :-
1. The construction of screws having heads in any part of their length such
heads being of any required forms as herein set forth described and illustrated.
2. The improved form of screwdriver and centre bit for the insertion of the
aforesaid screws as herein set forth described and illustrated.
3. The brace with interchangeable blocks for turning rods or bars in which one
end of the aforesaid screws have been inserted as herein set forth, described, and
illustrated.
Dated this 10th 3 of T... 1001
GRAHAM & GRAHAM,
Agents for Applicant.