IMPROVEMENTS IN SCREW CUTTING MACHINERY to be as follows:-
Year: 1884

page_text: I FREDERICK FOSTER of Niagara Works Eagle Wharf Road Hoxton in the
County of Middlesex Engineer do hereby declare the nature of my invention for
"IMPROVEMENTS IN SCREW CUTTING MACHINERY to be as follows:-
"
This invention relates to a means of cutting screw threads on hard woods such
as is required for wood stoppers that screw into bottles or any wooden article that
requires to have a short length of screw thread upon it. For this purpose I make
a circular cutter the teeth of which take the form of part of the top and part of
the base of the thread the form being made to agree with the form of screw thread
to be produced either a fine or coarse thread. This circular cutter I mount in a
frame similar to a lathe head as shewn in the accompanying drawings Fig 1 and 2
marked A the circular cutter being marked B. The stopper or other article to be
screwed is held in a self centreing chuck C fixed at the extremity of a spindle with
hand wheel D having a screw thread cut upon the spindle of a pitch corresponding
with the pitch of the screw it is required to produce and engaging in a corre-
sponding screw thread within the boss of the standard E. The boss of this
standard E is inclined more or less according to the pitch of the screw thread in
order to give the required "rake" to the cutter to provide against injuring the
screw thread as it is being produced This standard E is mounted in a transverse
slide F and its position in the slide F can be controlled by the lever G so as to
bring the work in contact with the cutter B and remove it from contact when
required. H represents a stop which can be regulated by means of the two set
nuts II' in order to control the depth to which the screw thread shall be cut and
consequently the diameter of the screw produced.

page_text: COMPLETE SPECIFICATION.
I FREDERICK FOSTER of 26 Eagle Wharf Road Hoxton in the County of
Middlesex Engineer do hereby declare the nature of my invention for IMPROVE
MENTS IN SCREW CUTTING MACHINERY and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
This invention relates to a means of cutting screw threads on hard woods such
as is required for wood stoppers that screw into bottles or any wooden article that
requires to have a short length of screw thread upon it. For this purpose I make
a circular cutter the teeth of which take the form of part of the top and part of
the base of the thread the form being made to agree with the form of screw thread
to be produced either a fine or coarse thread.
This circular cutter I mount in a frame similar to a lathe head as shewn in the
drawings (accompanying the provisional specification) Figs 1 and 2 marked A the
circular cutter being marked B. The stopper or other article to be screwed is held
in a self centering chuck C fixed at the extremity of a spindle with hand wheel D
having a screw thread cut upon the spindle of a pitch corresponding with the pitch
of the screw it is required to produce and engaging in a corresponding screw
thread within the boss of the standard E. The boss of this standard E is inclined
more or less according to the. pitch of the screw thread in order to give the
required "rake" to the cutter to provide against injuring the screw thread as it is
being produced. This standard E is mounted in a transverse slide F and its
position in the slide F can be controlled by the lever G so as to bring the work in
contact with the cutter B and remove it from contact when required. Or in place
of the lever G a cord may be used running over pullies, carrying at one end a
heavy weight to bring the work in contact with the cutter B and a trendle at the
other end by means of which the work can be removed from contact when required.
H represents a stop which can be regulated by means of the two set nuts I. I' in
order to control the depth to which the screw thread shall be cut and consequently
the diameter of the screw produced.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
The apparatus for cutting screw threads on short articles such as screw stoppers
by bringing the work while revolving and travelling forward at, the saine time, in
contact with the cutter, in a line inclined more or less to the axis of revolution of
the cutter, according to the greater or lesser inclination of the coarse or fine screw
thread required to be produced all substantially as described and illustrated and i
operating by means of a treadle and balance weight for withdrawing the work from
contact with the cutter in the manner described.
Dated this fourth day of June 1885.