Improvements in Stocks and Dies for Cutting Screw Threads.
Year: 1891

page_text: Date of Application, 9th Apr., 1891
Complete Specification Left, 7th Jan., 1892-Accepted, 20th Feb., 1892
PROVISIONAL SPECIFICATION.
Improvements in Stocks and Dies for Cutting Screw Threads.
We HENRI Wyss of 44 Rue Marcadet HENRI BALLUET of 38 Rue Sorbier
Engineers and AUGUSTE QUENTIN of 13 Rue Berger Draughtsman all of Paris
in the Republic of France do hereby declare the nature of this invention to be as
follows
The object of this invention is to provide a screwing cutting apparatus which can
be readily adapted for cutting screws of various diameters.
In an apparatus, constructed according to this invention the stock or holder is
made in parts hinged so that they can be closed together or opened out. These
parts have at their inward parts squared or equivalently formed recesses and also
rounded recesses in which recesses the correspondingly formed sides of the dies fit
the said dies being formed of two cylindrical parts separated by a squared cr
equivalently formed part on the periphery of which cylindrical parts are formed a
number of semi-circular or partly circular recesses which when the corresponding
recesses in the two dies are brought opposite each other form the different sized
dies for cutting the various sizes of screws for which the apparatus is adapted so
that with the same apparatus a number of different sized screws may be cut the
size being altered by opening out the parts of the stock, readjusting the dies, so as
to bring opposite each other the screwed recesses of the size requisite to cut the
required screw, and resecuring the parts of the stock. The meeting parts of
the stock may also have in them recesses for taking screw taps, for cutting internal
screw threads.
When the apparatus is closed the two parts are held firmly together by means
of a locking screw, which passes through a strap jointed to the stock. A regulating
screw is employed for accurately adjusting the relative positions of the two parts
of the stock.
The apparatus thus constructed is simple and durable and the dies can be readily
removed to be sharpened.
The changing of size is very simple being obtained by merely placing the corre-
sponding numbers of the screwed recesses on the two dies opposite each other and
clamping them together by means of the screw carried by the stock.
Costly fitting is not required and detached pieces such as pins and keys for
locking the dies in position are unnecessary.
Special wrenches are also unnecessary when the apparatus is arranged so as to
receive screw taps as aforesaid.
Very accurate size of screw can be obtained by means of the before mentioned
adjusting screw.
Dated this 9th day of April 1891.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Stocks and Dies for Cutting Screw Threads.
We, HENRI WYss of 44 Rue Marcadet, Mechanical Engineer, HENRI
BALLUET Locksmith, of 38 Rue Sorbier and AUGUSTE QUENTIN, Draughtsman,
of 34 Rue des Halles, all of Paris in the Republic of France, do hereby declare
Price 8d.1

page_text: the nature of this invention and in what manner the same
is to be per-
formed, to be particularly described and ascertained.in and by the following
statement :-
This improved screw cutting tool or combined stock and dies is represented in
the accompanying drawings in which
Fig. 1 is an inverted plan of the open.tool.the revolving dies being removed.
Fig. 2 is a plan thereof when closed, with the dies in position and ready
for use.
Fig. 3 shows one of the dies in section.
The tool consists of two arms forming a stock hinged at O and provided each
with a recess the inner surface or wall of which is of a hexagonal or other similar
shape which the similarly shaped dies are adapted to fit, and they are further
provided with a countersunk portion G which fits the rounded external edge
of the dies.
The dies FF" F, as will be seen from Figs. 2 and 3, are formed of two
cylindrical portions separated by a polygonal part. In the periphery of their
flanged edges are formed screw-threaded recesses 3, 4, 5, 6, etc. varying in size and
pitch. In the example shown there are six of these notches though their number
may be varied at will there being two dies at a time in the tool.
It will be understood however that by exchanging dies the pitch of the screw-
thread cut by the same tool may be varied indefinitely.
The stocks are provided with square slots or recesses D for the reception. of taps
for cutting internal screw-threads.
When the tool is closed its two arms may be screwed tightly together by means
of the thumb-screw C passing through a yoke. E pivotted at O'.
Before completing the junction of the two parts by means of the screw.C.the
proximity of the dies within those parts is precisely determined by means of the
set-screw B.
This improved screw-cutting tool offers many important advantages.
It is exceedingly simple and will remain fit for use for an almost indefinite period
of time the dies being removable and interchangeable so that they may at any time
be sharpened and always kept in the proper condition for producing clean threads.
Both the handling, or operation of the tool and the substitution of one set of dies
for another or of one pitch for another are exceedingly easy, this latter result. being
obtained simply by turning the dies in the tool in such a manner as to bring the
semi-circular recesses corresponding to the required, pitch opposite.to each other.
The cost of manufacture of this tool is greatly reduced inasmuch as.it.requires
no complicated adjustment or fitting together of parts and enables, all separate
devices such as pins and keys for tightening the guard-plates of the dies.to be
dispensed with.
There being special slots for the reception of taps no wrench.or key is necessary
and the special shape of the dies (Fig. 3) enables -very. short screw-threads to be
cut. The metal cuttings drop out of the tool of their own accord which.conse-
quently is never spoiled or damaged by them. Owing to the adjusting screw great
precision is ensured.
Having now particularly described.and.ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what
we claim is
1
1. A screw cutting tool with roller shaped rdies capable of adjustment as
required having six or any suitable number of sides and a flanged edge both of
which the stocks are adapted to fit "substantially as described and illustrated in the
accompanying drawings.
2. In a screw cutting tool the employment of adjusting and itightening screws
the latter of which is fitted within a pivotted yoke substantially as, described and
illustrated in the accompanying drawings.

page_text: 3. The combination and arrangement of parts constituting the improved screw
cutting tool substantially as described and illustrated in the accompanying
drawings.
Dated this 7th day of January 180°
W. P. THOMPSON & BOULT,
Agents for the Applicant.