Improvements in and relating to Lathes for Turning Carbon and other Hard Materials.
Year: 1891

page_text: Date claimed for Patent under Sect. 103 of Act,
being date of first Foreign Application (in
United States of America),
}
22nd Sept.,
1890
Date of Application (in United Kingdom), 13th Apr., 1891
Complete Specification Left. 13th Apr. 1891-Accepted, 13th June. 1891
COMPLETE SPECIFICATION.
Improvements in and relating to Lathes for Turning Carbon and
other Hard Materials.
I, NATHAN PAGE STEVENS, of Concord, in the County of Merrimack and State
of New Hampshire, United States of America, Gentleman, do hereby declare the
nature of my invention for IMPROVEMENTS IN AND RELATING TO LATHES FOR
TURNING CARBON AND OTHER HARD MATERIALS, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the following
statement :-
My invention relates to plug and socket cutters and a chuck for centreing and
holding the same upon a lathe spindle.
My object is to provide a cutter for use upon very hard materials-such, for
instance, as carbons and to make them so cheaply that the cutters may be
discarded after becoming dulled and replaced by new ones.
The invention consists in two or more cutters (male and female) stamped by a
suitable die from sheet-steel, and a suitable chuck, in which the same may be
clamped and centred upon a lathe, all of which will be fully set forth in the
following Specification and claims, and clearly illustrated in the accompanying
drawings, forming a part of same, of which-
Fig. 1 represents a double-ended lathe provided with guide-rests for the work
and one of my improved chucks at each end, each carrying one of my improved
cutters.
Fig. 2 is an elevation of one of my improved female cutters, and
Fig. 3 is a similar view of one of the male cutters.
Fig. 4 is an end view of one of the adjustable guides, which attaches to either
end of the lathe.
Fig. 5 represents the chuck in end elevation.
Figs. 6 and 7 are each a sectional elevation of the chuck in different positions.
Corresponding letters designate similar parts throughout the various views.
A represents a lathe having a single spindle B, mounted in two bearings a a and
carrying between said bearings a driving-pulley C. At each end of the lathe a
vertically-adjustable centreing-rest a' is mounted, upon which the work will
automatically centre itself by resting in the V-groove a while being fed up against
the cutters by an operator.
After numerous and various experiments I am convinced that no ordinary tools,
drills, &c., can be made to do service upon such material as carbon with any
degree of economy, as they will require constant care and attention to keep their
cutting-edge within a required scale, and for such work as joining electric-light
carbons by cutting them, as seen at F, Figs. 2 and 3, the expense of the necessary
tools is a serious item to be con-idered. Cutting-tools for this purpose must be
made quickly, else the expense of joining together the waste pieces of carbon will
be as great or greater than their original cost when whole. Hence 1 cut with

page_text: suitable dies the pieces D E from sheet-steel, each containing two or more of the
cutters, as will be seen by reference to Figs. 2 and 3. The piece D has slots d
which form the plug upon a piece of carbon F, and cutting-edges d', which form
the shoulder of said carbon, while the piece E is provided with projections e for
cutting a socket in a piece of carbon and the cutting-edges face off the end of
same, as at These edges d dee of the pieces D E are all brought to a cutting-
edge by a file, as indicated by the double lines in Figs. 2 and 3.
A simple and convenient chuck which use for these cutters consists of a
stationary and detachable jaw or clamp, respectively (II, held together by means
of an outer collar I, which may be rigidly secured to the former by a screw or pin
and provided with a set-screw i, which will bear upon the latter. The inside
diameter of the collar I equals the width between opposite cutters of the pieces DE,
which are inserted between the jaws GH, and thus readily centre themselves, the
shoulder g of the jaw G serving as a stop for the cutters. The larger or stationary
jaw G is provided with a tapering spindle g', which is forced into a socket in the
end of the lathe-spindle B. Two hands may work at this lathe at the same time,
one cutting the sockets at one end and the other turning the plugs of the carbons
at the other end. When a cutter becomes dull, the lathe is stopped, the chuck
opened, and the cutter turned around or reversed, and when all have been used
until dull the piece D or E is removed and another inserted.
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 combination of a chuck comprising two diametrically-divided jaws, an
exterior ring or collar rigidly fixed to one of said jaws, and reversible cutters
stamped by a die from sheet metal, the diameter of which equals the interior of
said collar, and a set-screw threaded to said collar for clamping said cutter between
the jaws.
2. The pieces D. E, stamped from sheet metal, provided with two or more cutters
arranged diametrically opposite, combined with a chuck divided diametrically and
provided with an exterior collar and set-screw threaded therein for clamping the
cutter between said jaws.
3. The pieces D E, stamped from sheet metal, provided with two or more cutters
arranged diametrically opposite, combined with a chuck divided diametrically and
provided with an exterior collar and set-screw threaded therein for clamping the
cutter between said jaws, and a vertically-adjustable guide-rest having a V-groove
therein formed horizontally and in line with the lathe-spindle for supporting and
centreing the carbons.
Dated this 13th day of April 1891
F. W. BARKER,
Applicant's Agent.