A Centrifugal Percussion Fuze for Igniting the Bursting Charges of Shells.
Year: 1887

page_text: Date of Application, 10th May, 1887
Complete Left, 20th Jan., 1888
Complete Accepted, 10th May, 1888
A Centrifugal Percussion Fuze for Igniting the Bursting Charges
of Shells.
We, JAMES HENRY BURKE Catherington Villa, Campbell Road Southsea, Lieutenant
in the Royal Navy, and ALFRED LEATHER, of North Ground Villa, Portsmouth, do
hereby declare the nature of this invention to be as follows
This fuze consists of the following parts, namely; The Body containing two
chambers; Top Cap with needle point and automatic spring shutter; Safety pin ;
Three segmental guards with springs attached ; Pellet with detonator and priming ;
Base Cap.
The segmental guards, when in the ordinary position, form a hollow cylinder inter-
posed between the pellet and top cap thus preventing any movement of the pellet and
so making the fuze safe to handle.
Each of these segmental guards is held in this position by a spring attached to it,
the heel of which spring presses against and lightly clips the lower part of the pellet
so as to prevent it from creeping forward towards the needle point during flight. As
a further means of obtaining safety in handling the fuze a safety pin is provided
which is pushed through a hole in the top cap and between one of the segmental guards
and the side of the fuze. A spring shutter is fitted on the outside of the top cap which
automatically flies into position on the removal of the safety pin so as to close the hole
through the top cap.
Before putting the shell into the gun, this safety pin must be removed; on the gun
being fired the rotation of the shell causes the three segmental guards to fly outwards
against the side of the fuze and so leave a free passage for the pellet towards the
needle point; when the shell experiences a sudden check in its velocity, either from
graze or impact, the pellet flies forward against the needle point and so fires the
detonator and priming.
Dated this Ninth day of May 1887.
JAMES HENRY BURKE,
Lieutenant Royal Navy.

page_text: We JAMES HENRY BURKE of Catherington Villa, Campbell Road, Southsea,
Commander in the Royal Navy and ALFRED LEATHER of North Ground Villa
Portsmouth 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:
The invention consists in a shell fuze in which the pellet, carrying the detonating cap,
is prevented from moving forward to strike the needle point by the interposition of
guards which are kept in position by springs under all circumstances except when the
fuze is made to spin.
Further, a spring arrangement is fitted to the side of the pellet to prevent the
same from creeping forward during flight but sufficiently weak to permit of the
pellet moving against the needle point when the shell experiences a suddon check
in its velocity.
Also a spring automatic shutter is fitted to close the hole through which the safety
pin passes on the latter being removed.
Fig. 1 is a section shewing the internal arrangements of the fuze wherein A is
the pellet and B are the guards kept pushed towards the centro of the fuze by
springs.
When the gun is fired the rotation of the shell causes these guards B to be thrust
outwards against the side of the fuze by centrifugal force and so leave a passage clear
for the pellet to move forward towards the needle point on the shell losing its velocity
suddenly by graze or impact.
The guards need not necessarily be three in number.
The spring C on the side of the pellet permits of a small forward movement
of the latter until the end of this spring bears against the stud, shown, which prevents
any further forward movement during flight unless a sudden loss of velocity is
experienced, when, the energy of the pellet would overcome the strength of the
spring C.
Fig. 2 shews a section through the guards B and their springs.
Fig. 3 is a plan of the upper side of the top cap of the fuze showing the automatic
spring shutter D for closing the safety pin hole.
Fig. 4 shows another application of the principle, the guards B¹ are kept pushed
inwards in front of the rim on the pellet by springs, as shown, until the fuze is spun
with sufficient rapidity to cause them to fly outwards.

page_text: said
Having now particularly described and ascertained the nature of my
Invention and in what manner the same is performed I declare that what I claim is :
1. A shell fuze having a safety arrangement of guards kept in position by
springs which guards can only be removed by centrifugal force due to the rotation
of the fuze.
2. A spring arrangement for preventing the pellet from creeping forward towards
the needle point during flight.
3. An automatic spring shutter for closing the safety pin hole after the removal of
the safety pin.
Dated this Nineteenth day of Jonny 1888