An Improved Tool Holder for Screw Cutting Lathes.
Year: 1898

page_text: Date of Application, 12th Oct., 1898
Complete Specification Left, 8th July, 1899-Accepted, 19th Aug., 1899
An Improved Tool Holder for Screw Cutting Lathes.
We, WILLIAM COPLEY and ARTHUR RAMSDEN COPLEY, of the Firm of Copley
and Son, of Exmoor Street, Halifax, in the County of York, Machine Tool Makers,
do hereby declare the nature of this invention to be as follows:-
The object of our invention is to construct a tool holder for screw cutting
lathes in which the tool may be capable of being made to swivel or cant from one
side to the other according to the character or formation of the screw to be cut,
the said tool holder being also capable of being employed to cut either right or
left hand screws.
In constructing a tool holder for purposes above described, the tool itself is
inserted into a groove formed in the head of a semicircular split bush made with
a split bolt which is secured in position by a washer and nut. In order to swivel
or cant tlie tool which is held in this semicircular split bush, a radial slot is
formed in the tool holder, proper, the head of which tool holder is curved to cor-
respond with the semicircular bush, and through said radial slot the screwed
bolt of the semicircular bush passes, and by unslackening the nut securing said
bolt, the semicircular bush, and with it the tool can be canted or swivelled as
before stated to suit the formation of the screw being cut.
By splitting the semicircular bush as before stated, the tool is, when the nut
is tightened up, firmly gripped and prevented from sliding or being forced away
from its work when in use.
The tool, which is made with a cutting edge at each end can be reversed in the
holder and then can be employed for cutting a left hand screw, in addition to
which the tool holder can be placed much nearer to its work than hitherto.
Dated this 11th day of October 1898
An improved Tool Holder for Screw Cutting Lathes.
We, WILLIAM COPLEY, and ARTHUR RAMSDEN COPLEY, of the Firm of Copley
and Son, of Exmoor Street, Halifax, in the County of York, Machine Tool Makers,
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 fol-
lowing statement:-
The object of our invention is to construct a tool holder for screwcutting lathes
in which the tool may be capable of being made to swivel or
cant"
from one

page_text: side to the other according to the character or formation of the screw to be cut,
the said tool holder being also capable of being employed to cut either right or
lefthand screws. In constructing a tool holder for purposes above described, the
tool itself is inserted into a groove formed in the head of a semicircular split
bush made with a split bolt which is secured in position by a washer and nut.
In order to swivel or "cant" the tool which is held in this semicircular split
bush, a radial slot is formed in the tool holder proper, the head of which tool
holder is curved to correspond with the semi-circular bush, and through said
radial slot the screwed bolt of the semicircular bush passes, and by unslackening
the nut securing said bolt, the semi-circular bush, and with it the tool can be
canted or swivelled as before stated to suit the formation of the screw being cut.
In the accompanying drawings Fig. 1 is end view, and Fig. 2 front view of
my improved tool holder. Fig. 3 is sectional end view shewing how the tool may
be "canted" or swivelled. Fig. 4 is side elevation.
Referring to the drawings 1 represents the tool. which is inserted into a
groove 2 cut in the semicircular split boss 3 provided with a screwed portion 3¹,
the curved surface of said split boss 3 being adapted to work against a corre-
sponding surface on the head 4' of the tool holder 4.
In order to permit of the canting or swivelling of the tool, to suit the varying
formations of screws of different characters, the head 41 of the tool holder 4. is
provided with a radial slot 5 through which the split bolt 31 of the bush 3 carry-
ing the tool 1 passes, said bolt being secured therein by nut 6 and washer 7 at
the angle required see Fig. 3.
The action of screwing up the nut 6 on the screwed bolt 3 securely fastens
the tool 1 in the semicircular bush 3, and prevents the tool from being forced
away from its work when in use.
The tool 1 is made with a cutting edge or surface at each end, and can thus be
reversed in the holder, whereby the same holder can be employed for cutting both
right and left handed screws, in addition to which the tool holder can be brought
much nearer to its work, and further, there is a great saving in tool metal.'
66
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
The combination, with a tool holder, of a curved head 4, a semicircular split
bush 3 adapted to work therein, and having a groove 2 to receive and grip the
tool, and a screwed projection 31 on said split bush passing through a radial
slot 5 in the curved head of the holder, and adapted to be secured therein by
washer and nut all substantially as herein shewn and for purposes set forth.
Dotad this 7th day of July 1899
TASKER & CROSSLEY,
Patent Agents, Halifax, Agents for the Applicants.