Improvements in the Manufacture of Explosive Projectiles.
Year: 1890

page_text: Date of Application, 24th July, 1890
Complete Specification Left, 24th Apr., 1891-Accepted, 24th July, 1891
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Explosive Projectiles.
I ABRAHAM MARTIN of 177 Aston Lane, Birmingham in the County of Warwick,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to the manufacture of explosive projectiles or shells having
the fuse fixed in the base, and the invention has for its object to provide an efficient
means of closing the base of the shell and to afford a sufficient length of screwthread
to prevent the blowing out of the fuse and the consequent failure of the shell to
burst under the force of the explosion.
According to my invention the base of the shell is formed by closing in or con-
tracting the cylindrical rear end of the shell behind or around a ring or bushing
which has been previously screwed into the body of the shell which is thus wholly
or partially imprisoned by the contracted end of the shell, the ring and the closed
in base of the shell, or the bushing only, as the case may be, being tapped to receive
the fuse. In either case the open rear end of the shell is first cut with an internal
screwthread in which the ring or bushing is then screwed. In the case of a ring,
it is screwed in a sufficient distance to admit of the end of the shell being turned in
entirely behind it by the action of suitable dies, a central hole being preserved in
the inwardly turned end by a suitable mandrel, and this hole, and that in the ring
being afterwards tapped to receive the fuse, the inwardly turned end and the ring
together affording a sufficient length of thread to prevent stripping.
In the case of a bushing, it is screwed in as before but is made of conical or
contracted form towards the rear, the end of the shell being afterwards closed in
around the part of lesser diameter so as to imprison it sufficiently to assist the
screw thread to retain it in place, this bushing having a through hole tapped in it
to receive the fuse.
Dated this 24th deveof July 1890
A. MARTIN.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Explosive Projectiles.
I, ABRAHAM MARTIN of 177, Aston Lane, Birmingham, in the County of
Warwick, Engineer, 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 :-
My invention relates to the manufacture of explosive projectiles or shells; and
the invention has for its object to efficiently close the base of the shell and provide
a screwed socket therein for the fuse, of sufficient length to prevent the blowing
out of the fuse and the consequent failure of the shell to burst under the force of
the explosion.
According to my invention, the base of the shell is formed by closing in or
contracting the internally screw threaded rear end of the shell behind or around an
externally screw threaded ring or bushing after the same has been screwed into the
body of the shell. The ring or bushing is thus wholly or partially imprisoned by
the contracted end of the shell, the fuse being screwed into a tapped hole passing
through both the closed-in base of the shell and the internal ring, or through the
bushing only, as the case may be.

page_text: Specification, wherein
one accompanying drawings, forming part of this
Figures 1, 2, and 3, illustrate, by central sections of a shell, successive stages of
closing in the base over an internal ring.
Figures 4 and 5 shew the same as applied to a conical bushing.
In either case the open cylindrical rear end of the shell A is first cut with an
internal screw-thread a in which the externally threaded ring B or bushing B' is
then screwed.
In the case of a ring it is screwed in a sufficient distance, as shewn in Figure 1,
to admit of the end of the shell being turned in entirely behind the ring, as shewn
in Figure 3. This is done by the action of suitable dies, the shell being previously
re-heated and brought first to the form shewn in Figure 2 and then to the final
form, Figure 3, a central hole C being preserved in the inwardly turned end A' by
a suitable mandrel or core carried by the die. This hole, extending through the
turned-in end of the shell and also through the ring, is afterwards tapped to receive
the fuse, the total length of screw threaded socket thus formed being sufficient to
prevent stripping.
In Figure 3 is represented, at D, the form of die used to bring the base of the
shell to the final form. The form of the other dies will be sufficiently evident.
In the case of a bushing, as shown in Figures 4 and 5, its cylindrical part is
screwed into the shell as before, but it is made of conical or contracted form towards
the rear, the conical part being preferably screw-threaded like the rest. After the
bushing has been screwed into position, the shell is heated and its rear end closed
in around the conical part of the bushing so as to imprison it sufficiently to assist
the screw-thread to retain it in place. The screw-thread of the closed-in part of
the shell engages with that of the conical part of the bushing, if it be threaded as
above mentioned, the whole length of the threaded part thus being effective for
retaining the bushing in place. The conical part might, however, be plain, in which
case the thread of the closed-in portion of the shell would be crushed against it.
This bushing has a through hole C in it, which is afterwards tapped to receive
the fuse.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what
I claim is
1. In the manufacture of shells or explosive projectiles, forming the base of the
shell by closing in or contracting the internally-threaded rear end of the shell
behind or around an externally-threaded ring or bushing screwed into the body of
the shell, substantially as, and for the purpose, specified.
2. In an explosive projectile or shell, the combination of the internally-threaded
body portion, an externally-threaded ring screwed therein, an inwardly-turned base
in rear of the ring, a screw-threaded socket passing through both, and a fuse screwed
therein, substantially as specified.
3. In an explosive projectile or shell, the combination of the internally-threaded
body portion, an externally-screwed bushing of partly cylindrical and partly conical
form screwed therein, and the rear end of the body portion contracted around the
conical part of the bushing, as described.
Dated this 23rd day of April 1901.
A. MARTIN.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.