Improvements in Fuses for Projectiles.
Year: 1890

page_text: Date of Application, 22nd Feb., 1890
Complete Specification Left 22nd Dec. 1590-Accented. 24th Jan. 1891
PROVISIONAL SPECIFICATION.
Improvements in Fuses for Projectiles.
I DAVID DUNCAN ESSON of 9 Crawthew Grove East Dulwich London S.E.
Engineer do hereby declare the nature of this invention to be as follows:-
It is a known fact that up to this date there has not been a really good and
reliable fuze in use. The faults attending fuzes are of different kinds. Some are apt
to fire prematurely while others totally miss fire.
To overcome these faults and others I construct a fuze, at the base end of which
I fit a flexible disc or a piston or both, and place under or above the one or the
other or between them a liquid or semi-liquid substance, such for instance as vaseline.
In firing the gun the powder-gases act upon this disc or piston forcing it forward,
the soft substance serving to prevent the powder gases from entering the interior of
the fuze
The disc or piston is combined with the pellet directly or indirectly so as to release
it and set it ready for action to ignite the charge of the shell when the gun is
fired.
DAVID DUNCAN ESSON,
9, Crawthew Grove, East Dulwich, London, S.E., Engineer.
COMPLETE SPECIFICATION.
Improvements in Fuses for Projectiles.
I, DAVID DUNCAN ESSON, of 47, Clapham Road, London, S.E., 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:-
It is a known fact that fuses as hitherto constructed have been found to be very
unreliable in their action, some being apt to fire prematurely while others totally
misfire.
.
The object of my invention is to provide a fuse which shall be thoroughly reliable
when subjected to falls or other violent shocks and so that the explosion cannot take
place until after the projectile has left the gun.
To overcome the defects common to fuses hitherto employed 1 construct a fuse, at
the base end of which I fit a flexible disc or piston, or both, and place under or above
the one or the other or between them, a liquid or semi-liquid substance such for
instance as vaseline, or preferably a plastic compound or mixture such as plumbago
and wax.
In firing the gun, the powder gases act upon the above mentioned disc and piston,
forcing it forward, the soft or plastic substance enclosed between the disc and piston
serving to prevent the powder gases from entering the interior of the fuse.
The disc or piston is combined directly or indirectly with the pellet and striking
pin, so as to release it and set it free to ignite the charge of the shell upon the impact
of the projectile with any obstructing object.
In the accompanying sheet of drawings,
Fig. 1 is a central longitudinal section of a fuse constructed in accordance with this
invention; the pellet with its striking or firing pin being shown in its normal or
safe position.
Fig. 2 is a similar view, showing the pellet and striking pin in the positions they
are caused to assume by the discharge of the gun.
Figs. 3 and 4 are details.

page_text: a, is the case of the fuse. b, is a screwed plug fitted within the outer or base end of
the fuse case and is provided with a central prolongation projecting into the interior
thereof, such prolongation being bored out centrally to receive a cylindrical piston or
plunger, c, which is free to move longitudinally therein. The outer or rear end of
said plug is formed with a slightly recessed or concave space for the reception of
the semi-fluid or plastic substance or other compound d, which is kept enclosed
therein by the thin flexible disc of metal e; the flexible disc e, being held in place by
the outer screwed plug f, in which there is a central opening g, through which the
powder gases can act upon the disc e, and piston c, where the gun is fired.
Another thin disc of metal h, is inserted within the opening of the hollow portion
of the plug b, between the end of the piston c, and the plastic substance or com-
pound d, which disc h, is rivetted in place by a slight projection formed around the
outside of the orifice for that purpose.
, is the pellet proper, carrying the striker or firing pin k; the pellet i, being hoid
securely in its normal or retracted position by the small cylindrical pellet or locking
bolt l, which is carried in the transverse openings m, formed in the pellet proper and
in corresponding openings formed through the prolongation of the screwed plug b.
This locking pellet 1, for a portion of its length centrally between the two ends, is
reduced in substance to a thin strip or bar of metal n, (see Fig. 3), so as to allow of
its being easily divided and cut away from the thicker portions l. 1, by the forward
passage of the piston c, which at its inner end, is formed with a cutting face c¹, or
chisel edge c, for that purpose, as more clearly shown in Fig. 4.
The gases generated upon the discharge of the gun, force the thin metal disc e,
inwards and press the enclosed plastic material d, together with the smaller disc h,
against the piston c, which on its forward movement within the plug b, by means of
its cutting face c¹ c², severs the pellet 1, thereby forcing the reduced central portion n,
thereof into the position shown in Fig. 2; where it then remains stationary, and so
leaving the two severed ends of the pellet 1, free.
The centrifugal force generated by the rotation of the projectile causes the freed
and severed ends of the pellet 1, to fly outwards within the openings m, in the pellet
roper, which is thus set free to strike the detonator o, and fire the charge upon
he impact of the projectile with any obstructing object.
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
claim is:-
Firstly. In a fuse for explosive projectiles, the use of a liquid, semi-liquid or com
pound plastic mixture or material, contained and confined between a yielding or
flexible disc or diaphragm and a piston or plunger, substantially as and for the
purposes herein described and shown by the drawings.
Secondly. In a fuse for explosive projectiles the use of a liquid, semi-liquid or com-
pound plastic mixture or material contained and confined between a yielding or
flexible disc or diaphragm and a piston, or plunger combined and operating with the
pellet, the striking pin, k, and a locking pellet 1, substantially as and for the
purposes herein set forth and shown by the drawings.
Dated this 22nd December 1890..
DAVID DUNCAN ESSON.