Improvements in Lathes for Manufacturing Bullets and like articles.
Year: 1897

page_text: Date of Application, 2nd Oct., 1897-Accepted 26th Feb.,
1898
COMPLETE SPECIFICATION.
Improvements in Lathes for Manufacturing Bullets and like articles.
We, CARL ROBERT KAPPLER, Architect, of Gochsheim, near Schweinfurt, and
FRIEDRICH SCHUNK, Engineer, of 9, Schanzen, Schweinfurt, both in the Empire
of Germany, 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 following statement:-
This invention relates to that class of machine tool known as the hollow spindle
lathe where the rod or bar to be operated on is passed through or placed in the
axial centre of the lathe spindle.
This invention consists of an automatic machine tool for manufacturing bullets
and like articles where the rod of metal or other material from which the articles
are made is passed through a hollow revolving spindle and there fixed, the spindle
head carrying forward the protruding bar through a stationary tool head carrying
cutters so arranged and operated that the article is accurately profiled and
detached from the bar rapidly and correctly.
The method of carrying this invention into effect in the manufacture of bullets
is illustrated in the accompanying drawings as follows:-
Figure 1 is a side elevation partly in section of the machine.
Figure 2 is an end elevation.
Upon a bed plate A there is mounted a sliding pedestal d carrying a hollow
spindle e and this hollow spindle has placed upon it the fast and loose pulleys g, h,
Rigidly connected to or forming part of the spindle e is a gripping chuck so
that when the bar a from which the bullets are manufactured is placed in the
position shown the chuck is tightened and causes the bar a to rotate with the
spindle when the machine is operated. Any of the types of well known feed
mechanism in use on machine tools is arranged in conjunction with the sliding
pedestal to move it forward in the direction of the tool head c at regular
intervals distances equal to the length of the bullets.
The tool head e consists of two co-axial discs r and m mounted upon a bracket /
which is securely attached to the bed plate A. Upon the larger disc m three
0 levers n are pivotted at their outer ends, while at their inner ends they are
attached by suitable pins n² to three short angle levers o; the said angle levers
at their other extremity being attached to pins p. The pins p work in slots q
arranged on the disc m eccentrically to the centre of that disc, and the inner ends
of the pins project through in the path of the driving devices placed upon the
5 disc r.
The said driving devices may consist of radial grooves in the face of the
disc embracing the ends of the pins p although any equivalent device may be
employed. The disc m is fixed against rotation by the sleeve m¹ while the disc r
is partially rotated at suitable intervals by the cam x acting upon the tail of the
weighted lever y which is attached to the disc r.
10
The cutting tools are arranged in pairs t and u upon the pins n² and as shown
in side elevation on Figure the first tool t is profiled so that the point of the
bullet is formed and almost detached from the bar a at one operation, while the
tool is a thin cutting one whose function is to finish and sever the bullets from

page_text: the bar when the bar is moved forward. The side elevation of both tools t and u
as shown in Figure 2 is precisely similar,-and is of a circular form with a section v
removed so as to form a cutting edge and by this formation the tools can be
ground on this cut away portion without touching the profile and thus a uniform
result in turning be always obtained.
The operation of the herein before described mechanism is as follows,―The bar a
is fixed in the sliding pedestal d and the feed mechanism carries it forward through
the cutter-head c into the path of the three pairs of cutters & and u, then the cam
through the lever y partially rotates the disc r a sufficient distance to drive the
The cutting
pins slowly along the eccentric slot q in the stationary disc m.
edges of the tools thus gradually bear in upon the bar a and the profiling tools t
nearly complete the bullet. Upon the next forward movement of the pedestal d
the bullet is finished and cut off by the tools u while simultaneously with this
operation the cutters are operating on another. It must be clearly understood
that the bar to be operated on may be gripped and centred by any automatic self
centreing chuck; that to effect the radial displacement of the cutting tools both
or either of the discs may be oppositely rotated by any suitable mechanism, and
that the eccentric slots may be placed upon either of the discs, all without depart-
ing from the subject of the present.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is:-
1. In machine tools for manufacturing bullets and like articles the arrangement
in combination of a hollow spindle pedestal upon a lathe bed gripping the bar
to be operated upon, rotating it and travelling it forward automatically at
periodic intervals in the path of a stationary tool head upon which, are fixed
concentric cutters, and suitable feed mechanism operating these cutters to form
the article required during the periodic rests of the spindle pedestal feed
mechanism all substantially as and for the purposes hereinbefore described.
2. In machine tools for manufacturing bullets and like articles, the tool head c
with co-axial discs, three sets of cutters u and t all constructed and operated sub-
stantially as herein before described, with reference to Figures 1 and 2 of the
accompanying drawings.
3. In machine tools for manufacturing bullets constructed substantially as
herein before described with reference to the drawings the provision of cutting
tools with a circular elevation and a removed section, as a means for leaving
'the cutting profile intact when grinding the tool upon the removed section to form
the cutting edge all substantially as and for the purpose herein before described.
4. An improved machine tool for manufacturing bullets and like articles sub-
stantially as and for the purpose hereinbefore described with reference to the
accompanying drawings.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.