An Improvement in Percussion Fuses for Shells.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
An Improvement in Percussion Fuses for Shells.
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Chancery Lane, in the County
of London, Chartered Patent Agent, do hereby declare the nature of this inven-
tion (as communicated to me from abroad by Arthur Basil Markham, at present
of Hotel de Flandre, Calais, France) to be as follows:-
When a shell is intended for penetrating armour, the percussion fuse cannot
be arranged in the head which requires to be strong hard metal integral with the
body of the shell, and when the percussion fuse is inserted in the base of the
shell there is great risk of premature explosion. This invention relates to the
construction of a percussion fuse and its arrangement in the side of the shell,
such as to avoid interference with strength and solidity of a head suited for pene-
tration, and also to avoid the risk of premature explosion, which results from
placing the fuse in the base.
For this purpose the case of the percussion fuse is made of cylindrical form and
is screwed into the side of the shell just in front of the driving band by which
it is protected from the flame of the fired gun charge. The interior of the case
is divided into three compartments, in front, the magazine containing the
igniting charge, immediately behind it the detonator, and behind this, the pellet
or striker which is held back by a spring and through the rear part of which
passes a bolt engaged in a recess in that side of the case which is next the inside
of the shell, this bolt being pressed into the recess by a light spring. There is
also through the pellet a hole through which is inserted a safety pin having
attached to its outer end a ring by which it can be pulled out. The fuse is sunk
in the side of the shell leaving outside of it a shallow recess in which the ring
lies flat, and is covered by paper or fabric cemented on the shell. Thus, while
the shell is being stored or transported, the striker is held by the safety pin so
that it cannot move to strike the detonator.
When the shell is to be put into the gun, the cemented cover of the ring is
removed and the safety pin is pulled out, but the striker is still held in position
by the internal bolt.
When the shell is fired the centrifugal force resulting from the rotation im-
parted by the rifling causes the bolt to move outwards out of the recess in which
it was engaged, and the striker is then held back only by the spring in front of
it. When the shell is arrested in its flight the striker in virtue of its momentum,
shoots forward striking the detonator and firing the fuse charge, which in its turn
fires the charge of the shell.
Dated this 31st day of May 1808

page_text: I, OLIVER IMRAY, of Birkbeck Bank Chambers, Chancery Lane, in the County
of London, Chartered Patent Agent, do hereby declare the nature of this inven-
tion (as communicated to me from abroad by Arthur Basil Markham, at present
of Hotel de Flandre, Calais, France) and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
When a shell is intended for penetrating armour, the percussion fuse cannot
be arranged in the head which requires to be strong hard metal integral with the
body of the shell, and when the percussion fuse is inserted in the base of the
shell there is great risk of premature explosion.
This invention relates to the construction of a percussion fuse and its arrange-
ment in the side of the shell, so as to avoid interference with strength and solid-
ity of a head suited for penetration, and also to avoid the risk of premature
explosion, which results from placing the fuse in the base.
For this purpose the shell and its fuse are arranged as I shall describe refer-
ring to the accompanying drawings. Figure 1 is a longitudinal section of the
shell, Figure 2 shews to an enlarged scale a part of the section with the fuse
according to my invention in position. Figure 3 is a transverse section of the
fuse on the line 3-3 of Figure 2.
As shewn in Figure 1 the shell A has in its base a charging hole closed by a screw
plug B over which is a safety disc C of lead having its edges forced by pressure
on the disc into an annular dovetail formed in the base. Dis the usual driving
band, at some height above which the wall of the shell is thickened at E so as to
give sufficient depth for screwing the fuse F into a hole in the thickened part and
also to make up for the weakening due to the hole. The fuse is bored to receive
a cylindrical pellet striker G within which is fitted to slide a spring bolt H.
Near one side of the fuse is a cavity or magazine I containing the ignition fuse,
and this communicates with the bore of the fuse by an opening in which is fixed
a detonating cap and anvil J. The sides of the fuse and the pellet are bored to
receive a safety pin K to which is hinged a ring L that lies in a recess formed
in the side of the fuse, and is usually covered by paper or fabric cemented on the
face of the fuse. Q is a filling ring through which and the pellet G a hole is
bored to receive a safety wire R. The magazine I being charged the pellet G
with its spring bolt and filling ring Q being introduced into the bore of the fuse
and held by the safety pin K and wire R, the bottom M is screwed in, a segmen-
tal filling piece N is fixed by a screw, the fuse F is screwed into the side of the
shell with a packing washer interposed and prevented from turning by a screw P,
and the shell is ready for use. Before loading it into the gun, the paper or fabric
covering the ring L is torn off and the ring is pulled so as to withdraw the safety
pin K. When the gun is fired and the shell is caused to rotate by the rifling, the
spring bolt H is caused by centrifugal force to move outwards in opposition to the
spring, its end being thus withdrawn from a recess in the bore of the fuse, leaving
the pellet G free. On the shell striking any object, the pellet G, owing to its
momentum, breaks the wire R and flies forward, its pin point striking the deton-
ating cap and so firing the ignition fuse I, which fires the explosive charge in
the shell.
Although I have shewn an ignition fuse fired by a cap, obviously' other known
percussion fuses may be employed.

page_text: Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I claim is: -
1. A shell having a percussion fuse fixed in its side beyond the driving band,
substantially as described.
2. A percussion fuse adapted to be fixed in the side of a shell, constructed and
operating substantially as described with reference to the drawings.
Dated this 23rd day of February 1899.
ABEL & IMRAY,
Agents for the Applicant.