CERTAIN IMPROVEMENTS IN THE METHOD OR METHODS OF MAKING SCREWS OF IRON, BRASS, STEEL, OR OTHER METALS, FOR THE USE OF ALL KINDS OF WOOD WORK
Year: 1817

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GERARD COLBERT, of Winsley Street, in the Parish of St. Marylebone, in the
County of Middlesex, Mechanical Watchmaker, do send greeting.
WHEREAS His most Excellent Majesty King George the Third, by Llis
Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Thirteenth day of
May, in the fifty-seventh year of His reign, did give and grant unto me,
the said John Gerard Colbert, my executors, administrators, and assigns,
His special licence, full power, sole privilege and authority, that I, the said
John Gerard Colbert, my executors, administrators, and assigns, during the
term of years therein expressed, should and lawfully might make, use,
exercise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, an Invention communicated to me by a certain foreigner residing
abroad, of "CERTAIN IMPROVEMENTS IN THE METHOD OR METHODS OF MAKING
SCREWS OF IRON, BRASS, STEEL, OR OTHER METALS, FOR THE USE OF ALL KINDS OF
WOOD WORK;" in which Letters Patent there is contained a proviso, obliging
me, the said John Gerard Colbert, under my hand and seal, to cause a
particular description or explanation or communication of the said discovery or
Invention, and in what manner the same is to be used, to be inrolled in His
Majesty's High Court of Chancery within two months next and immediately
after the date of the said recited Letters Patent, as in and by the same
(relation being thereunto had) may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the
said John Gerard Colbert, do hereby specify and describe and ascertain the
nature of the said Invention, and the manner of effecting and performing the
same in manner following, that is to say:-

page_text: The nature and intent of the said Invention is the construction and arrange-
ment, use and application, of certain implements, machines, and tools herein-after
described, for the purpose and to the effect of producing screws of metal (for
screwing into wood for the usual purposes and uses of carpentry, joinery, &c.)
with more facility and accuracy of workmanship, and of superior fabric, than
those heretofore made for the same purposes. And I do declare that my
manner of effecting and performing the same is fully described and set forth
in the following Specification, having reference to the annexed explanatory
Drawings.
Figures 1 and 2 respectively represent side and perpendicular geometrical
views of my method of cutting the required lengths of wire for screws of the
various lengths required. Figure 1 is the side view of the same; a, a, a, is
the lower piece of a pair of cutting shears; this is fixed to a work bench or other
solid frame; the upper part b, b, works on a centre d, by the handle c; e, e,
is the face of a plate used to regulate the lengths of wire, to be cut adjustible
by apparatus shewn in Fig. 2.
Fig. 2 is a perpendicular geometrical view of the same, in which the same
letters of reference are affixed respectively to the same parts; e, e, is the upper
cdge of the plato e, e; and 9, 9, an horizontal face of the same plate; this
plate is adjustible as to its distance from the cutters a and b, by a sliding
motion on the two bars h, h, on sockets i, i. To cut the wires, I elevate the
upper arm of the shears, and introduce the wires horizontally and at right
angles to the face of the shears, and as far between the cutters as the vertical
plate e, e, will allow. I then work the shears in the usual manner of shears,
and similar cutting instruments; the required length of the wires being cut,
they are placed between the cheeks of a vice, Fig. 3, in a groove or cavity of
suitable dimensions to the size required, and the cheeks of the vice being closed,
the head of the intended screw is formed by the spreading of the metal by
strokes of a hammer; the solid form of the intended screw thus obtained, there
remains the thread to be cut on the cylinder of the length, and the nick or cut
to be made across the head; the thread is cut and the head of the screw
turned ready for the making of the nick, or cut by the machinery represented
in Figures 4, 5, 6, and 7. a, a, a, is a steel axis working in supports
or uprights b, c, d, on a frame D, D; at the extremity e of the axis
a piece crosses it at right angles, to which is affixed, by screws and nuts,
the two bent arms, f, f, f, f, which move on the screws 9, 9, as centers;
each is furnished with a strong spring h, which bears against the axis and
presses the corresponding extremity i strongly towards each other; in each of
these extremities i, i, is fixed by dovetailed slides and screws a steel cutter k; m

page_text: is a conical tube, which may be moved forward along the axis a, a, a, (towards
the end to which the bent arms f, f, are fixed) for the purpose hercin-after
described, to cut the thread of the screw, and turn the head of it. I place the
piece of wire of which the screw is intended to be made between the holding
pieces ff, the head of the intended screw between and just within the
extremities of the two cutters k, k, as shewn in Figure 5.
the
The Figure 6 represents a side elevation of a motal frame of two parts a and b,
opening from each other on the joint at c, by the handle or stem d, the upper or
moveable piece a moving between two check pieces, of which one is seen at e;
into each of these pieces a and and in a direction at right angles to their
length, is placed in dovetailed grooves, and there secured by screws, a steel
cutter having teeth or being serrated in the usual way for the purpose of cutting
a screw thread on a metal cylinder introduced between them; these pieces are
shewn in the Figure at g and h, and they are sufficiently held together for that
purpose by the action of the lever and weight shewn in the Figure at m and n;
this part of the machinery is placed, when in use, in a direction at right angles
to the direction of the piece shewn at Figure 4. The cutters gand h being
directly opposite to the extremities of the cutters k, k, of the Figure 4, and
within a small distance of it, so that the wire introduced and held by one
extremity by the cutters h, k, may by the other extremity introduce itself between
the serrated or toothed cutters g, h, of Figure 6. The position here described
for the piece represented in Figure 6 is shewn in the Drawing of Figure 4, at
a, y, z, which represents a perpendicular geometrical view of the same;
same parts of it being respectively marked with the same letters of reference as
in the side elevation of the same piece, shewn at Fig. 6. To work the said
machinery, I proceed thus: the Figure 7 is a front elevation of the upright
piece d of Figure 4, shewing an apeture o, a thin steel edge piece 2, %,
moveable on a center r. It has a suspended weight W at a little distance beyond
the center, and a treadle S afixed to the other extremity. A steel screw R is
fixed to the extremity of the axis a, a, Figure 4, and secured by a small screw T;
this screw R. passes through the aperture o of Figure 4 without touching it;
when the treadle is not pressed, the steel edge z, z, remains clear of the screw R,
but when the treadle is pressed the steel edge is forced to enter one of the threads
of the screw R; this being done, and the axis a, a, made to revolve by the box
B, B, or any other well-known method of turning an axis, the axis being cylin-
drical through its whole length, will, by the action of the screw R on the fixed
edge z, make a forward progress, viz., towards that part of the machinery
marked a, y, z, and the rate of that progressive advance will be always regulated
and be adjustible by the fineness of the screw R. If the screw R be coarser,

page_text: the progress will be quicker, and vice versa; for this purpose of regulation and
adjustment the screw R may be changed at pleasure; the aforesaid progressive
advance of the axis a, a, will thus force the wire placed as already described at
k, k, into the small space between the screw cutters g, h, of Figure 6, and will
thus produce the thread of the screw. I now move forward the conical piece m
of Figure 4 over the bent arms f,f,f,f, so as by means of the rollers 7, 7, and
the springs h, h, the extremities i, i, are separated a little, and with them the
cutters, k; the new screw which was before held by the cutters k, k, is thus
released from them, and is now held between the screw cutters g and h of
Figure 6, but is still at liberty to turn on its thread; a pressure on the handle t,
such as to bring the screw k, Figure 5, to bear on the spring a, will hold the
screw more firmly, so that it cannot be turned, and now if the conical piece m
be moved back on the axis a, a, to its former situation, so that the cutters k, k,
may again approach each other, I then cause the axis a, a, to revolve, on which
the cutters k, k, turn and form the level of the head of the screw. I then slide
the conical piece a little distance over the bent arms f, f.f.f, as before, so
as to detach the cutters k, k, from the screw. I then release the pressure
on the treadle S, of Figure 7, and thus cause the steel edge z to leave the
thread of the screw R, Fig. 4. I then again cause the axis a, a, to revolve,
and the small cutter marked *, Figure 3, at the extremity of the axis will turn
the flat surface of the head of the screw; the screw is now compleated except
the nick or cut in the head. I now by means of the handle t of the picce
a, y, z, move the upper part of the said piece on its lower part by the joint
or center at C (Figure 6), and I then lift the axis a, a, a little way upwards
by that extremity of it which has the cutters fixed to it, and the screw so far
formed as described, will drop out and clear of the machinery. The axis a, a,
Figure 4, may be lifted as described by means of a contrivance shewn in
Figure 8, in which Figure, is a front elevation of the upright piece also
marked b, in Fig. 4; in this upright the part of it in which is the aperture y,
through which the axis passes, has a sliding motion up or down sufficient to
allow the lifting of the axis as described. I form the nick or cut in the head of
the screw by means of the machinery described as follows:-Fig. 9 is a geome-
trical plan of a rectangular box or frame, of which A, B, C, D, is the lower
part, and E, E, two lids or covers, which are in this Figure shown as opened and
thrown back to shew the interior of the frame; the pieces G, G, and M, M,
form a channel or groove, in which may be introduced the metal slide I, I,
which passes on through the whole length of the frame; it passes under the
projections of the screw heads h, h, h, h, which thus confine it to its intende
place; the plate I, I, is perforated, as shown in the Drawing, to receive the

page_text: screws on which the machine is intended to operate. They are placed in it,
as shewn at Figure 10, in which I, I, represents a part of the slide; and S, S,
the heads of screws placed in it. The plate I, I, being passed entirely into
the frame as far as the projecting pink allows, the unfinished screws are placed
in it, and the covers E, E, are shut down and fastened, as represented in
Figure 11, by the levers P, P. The covers E, E, when they are shut down,
do not quite meet, but leave a narrow open space (shewn in Figure 11,
at N, N,) through which the blade of a steel saw is introduced, and with which
the heads of all the screws placed in the machine have their nicks or cuts
made at the same time. Figure 12 is a side elevation of the saw; and
Figure 13, a cross or transverse section; Figure 14 is a cross section of the
piece shewn in Figures 9 and 10, with the introduction of the saw k to the
space left between the covers E, E, Figure 11. I also arrange the frame,
Figure 11, in a lathe or similar machine, so as to direct the action of a circular
revolving steel saw through the open space N, N, Figure 11, for the purpose
of cutting the nicks or cuts in the heads of the screws.
I further declare that I have set forth in this descriptive Specification my
arrangements and contrivances for the effecting the aforesaid purposes, and
that the same may be modified according to the scale and extent of the manu-
factory, and that they are capable of receiving all such auxiliary assistance
which the application of powerful movers and their necessary apparatus can
give them. I also use any of the suitable metals which my aforesaid purposes
require.
In witness whereof, I, the said John Gerard Colbert, have hereunto set