Year: 1886

page_text: I, HENRY COOPER SEDDON, of Her Majesty's Dockyard, Portsmouth, in the County
of Hants, Lieutenant Colonel in the Royal Engineers and Colonel in the Army, do
hereby declare the nature of this invention to be as follows
The object of my invention is to produce a safety percussion fuze that shall be very
sensitive, but shall nevertheless not be liable to accidental discharge. For this purpose
I employ a series of loose balls within a chamber in the fuze that has to be traversed
by the firing pin or by the cylinder or part of the fuze that carries the detonator in
order that the latter may be discharged the arrangement being such that the longi-
tudinal movement of the firing pin or of the detonator necessary to effect the discharge
shall be prevented by the said balls except when they are, by centrifugal force due
to rapid rotation of the projectile, thrown outward so as to assume an annular arrange-
ment against the wall of the chamber that contains them thus leaving a central space
just sufficient to allow of the passage of the cylinder or part that carries the pin or
the detonator as the case may be. The said cylinder or part in one arrangement, is
at that part thereof which serves to close one end of the chamber containing the balls
made slightly concave so that the balls may tend to assemble near the longitudinal
axis of the fuze when its axis is vertical or approximately so. The other end of the
ball containing chamber may be similarly formed for the same purpose.
When the axis of the fuze is not vertical or approximately so, the balls will
accumulate in the part of the chamber that is for the time being lowest. Fuzes in
various forms may he made to operate on the principle of my invention as set
forth above..
W. LLOYD WISE.
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Percussion Fuzes for Projectiles.
I, HENRY COOPER SEDDON, of Her Majesty's Dockyard, Portsmouth, in the County
of Hants, Lieutenant Colonel in the Royal Engineers and Colonel in the Army, 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 object of my invention is to produce a safety percussion fuze that shall be very
sensitive, but shall nevertheless not be liable to accidental discharge. For this purpose
employ a series of loose balls within a chamber in the fuze that has to be traversed
by the cylinder or part of the fuze that carries the firing pin or-the detonator-as
the case may be in order that the latter may be discharged, the arrangement being
such that the longitudinal movement of the firing pin or of the detonator necessary to
effect the discharge shall be prevented by the said balls except when they are, by
centrifugal force due to rapid rotation of the projectile, thrown outward so as to
assume an annular arrangement against the wall of the chamber that contains them
thus leaving a clear central space for the passage of the cylinder or part that carries
the pin or the detonator as the case may be. The said cylinder or part in one arrange-
ment, may be at that part thereof which serves to close one end of the chamber
containing the balls made slightly concave so that the balls may tend to assemble near
the longitudinal axis of the fuze when its axis is vertical or approximately so. The
other end of the ball containing chamber may be similarly formed for the same
purpose. When the axis of the fuze is not vertical or approximately so, the balls will
accumulate in the part of the chamber that is for the time being lowest. Fuzes in
various forms may be made to operate on the principle of my invention as set
forth above.
In the accompanying drawings which illustrate percussion fuzes according to my
invention double full size, of the British general service fuze.
Fig. 1 shows in longitudinal section a fuze with the firing pin or striker attached
to a movable hollow cylinder through which the flame passes to the firing charge.
Fig. 2 is a plan of the cylinder with the firing pin or striker.
Figs. 3 are detached views of the striker.
Fig. 4 is a section in the line A B of Fig. 2.
Fig. 5 is a section in the line CD of Fig. 2.
Fig. 6 shows in longitudinal section a fuze with the firing pin or striker attached to
a movable solid cylinder and arranged for the base of a shell.
Fig. 7 shows in longitudinal section a fuze with the firing pin or striker fixed and
the detonator attached to a movable hollow cylinder partly through which the flame
passes to the firing charge, the parts being shown in the relative positions they occupy
during flight of the projectile.
Fig. 8 is a plan of the top.

page_text: Fig. 13 is a section in the line CD of Fig. 8.
Fig. 14 is a section in the line E F of Fig. 8.
Figs. 15 are detailed views of the locking key and firing pin or striker.
Fig. 16 shows in section the head of a fuze in which the details of construction are
somewhat modified.
Figs. 17 are details of the locking key and firing pin or striker illustrated in
Fig. 16.
Referring to the arrangement illustrated in Figs. 1 to 5 inclusive-1 is the outer
body (the outside screw thread on which is not shown). In this outer body there
are four interior divisions or chambers, viz: a chamber containing the detonating
powder 2 in a chamber 3 within a removable screw plug 4; the ball chamber 5
containing the balls 6, and through which chamber the end of the metal cylinder 7 with
firing pin or striker 8 has to pass; the bolt chamber 9 containing the hollow metal
cylinder 7 fitted with the firing pin 8, the said cylinder being hollow down the
centre to allow of the flame from the detonating powder passing to the priming
charge 10 (the projections 11 at the sides of the cylinder 7 work in slots 12 in
the side of the chamber 9, but I do not consider these projections and slots essen-
tial); and a chamber for the priming charge 10 in a chamber 13 within a removable
screw plug 14.
The use of a removable chamber 13 as described for the priming charge presents
important advantages; it admits of readily inserting a fresh charge of powder when-
ever it may for any reason be desirable to do so; also it will enable the fuzes to be
stored with greater safety by using, whilst they are in store, plugs which can be
removed, and for which the charged powder chambers can be substituted when the
fuzes are required to be used.
In making fuzes according to my invention, the number of the balls and their size
should be such that, when the fuze is on its side, the balls shall extend above the lower
half or centre of the chamber containing them.
It will be seen that the form of the chamber 5 and the number and size of the balls
are such that when a projectile containing such a fuze is in rapid rotation during its
flight the balls will be caused by centrifugal force to assume an annular arrangement
within the chamber 5 so as to leave a clear central space just sufficient for the free passage
of the end of the cylinder that carries (in the arrangement just described) the firing
pin or striker, or (as in arrangements to be hereinafter described,) the detonator, as
the case may be, and that, with such an arrangement, while guarding against impedi-
ment to the relative forward movement at the proper time of the firing pin or striker,
or of the detonator, as the case may be, I at the same time effectually prevent all risk
of accidental explosion arising from the occurrence of such relative forward movement
when the fuze is at rest. The annular recess for the balls in the body of the fuze may
be of any depth, at right angles to the axis of the fuze, of from about one to two
diameters of the balls used.
Referring to the modification illustrated in Fig. 6, it will be seen that in this case
the chamber containing the priming charge, instead of being situated at the same side
of the ball chamber as the cylinder that carries the firing pin or striker, is placed at
the other end of the fuze, and the detonator is interposed between the firing pin or
striker and the priming chamber.
The cylinder 7 is solid, and the firing pin 8 is screwed into it. The cylinder can
be readily withdrawn in this case by unscrewing the plug 15. Parts corresponding
to those comprised in the previously described arrangement are marked with the
same numbers.
I will now describe the modification illustrated in Figs. 7 to 15 inclusive, in which

page_text: again the same reference numbers are used to denote parts corresponding to those
illustrated in the previously described arrangements. In this case the chamber 3
containing the detonating powder 2 is carried in a hollow cylinder 7, and as an
additional safeguard against the firing pin or striker and the detonator coming into
contact, the firing pin or striker is formed with flanges or projections 16 which, when
turned in one direction, serve to lock (that is to say, prevent the longitudinal move-
ment of the cylinder 7 containing the detonator, and, when turned in another
direction, leave the said cylinder with the detonator free to move longitudinally when
not otherwise impeded.
On reference to Fig. 10, it will be seen that there is formed in the end of the
cylinder 7 a transverse narrow chamber or slot 17 sufficiently wide to receive the
parts 16 and 18 of or connected with the firing pin or striker when it is turned into
the position shown in Fig. 7, but when the firing pin or striker is turned so that its
parts 16 and 18 are at a sufficient angle with the chamber or slot 17, endwise move-
ment of the cylinder 7 will be arrested by the metal thereof coming into contact with
the shoulders or projections 16.
To ensure the shoulders or projections 16 entering the chamber or slot 17, the
cylinder 7 is shown as being formed with projections working in slots 12 in the body
of the fuse.
The firing pin or striker 8 is fixed to the cap or plate 19, there being a square
part 20 that enters a corresponding hole in 19 to which the firing pin or striker is
fastened by a screw 21.
22 and 22ª are recesses in the screw plug 31, and 23, 23ª are notches cut through
the top plate 19, so arranged that the latter can be turned through a 4 of a circle by
inserting a key in the notches 23, 23. The recess 22ª is wider than 22 in order to
admit a stop 23 on the underside of plate 19, which prevents the possibility of the
latter, with the shouldered striker attached, being turned beyond the necessary of a
circle, to ensure the shoulders of the striker exactly coinciding with the slot in the
cylinder 7 through which they have to pass to allow of the firing pin striking the
detonator.
24 and 25 are recesses in the underside of the cap or plate 19 to receive a knob 26
carried by a spring 27. When the position of the cap is such that the knob 26 enters
the recess 25, the cylinder 7 carrying the detonator is (so far as respects the locking
action of the firing pin or striker) free to move longitudinally; but when the cap or
plate 19 is turned so that the knob 26 enters the recess 24, the position of the firing
pin or striker is such as to lock the cylinder 7 containing the detonator.
28 and 29 are nicks or marks on the outer surface of the body of the fuze to
indicate at a glance whether the cylinder and detonator are locked or unlocked. By
removing the screw 21 the cap or plate 19 can be taken off, screw 30 taken out, the
plug 31 unscrewed, and thus access to the ball chamber and other interior parts can
be gained. The priming chamber can be screwed from the other end of the fuze, and
access to its interior can be gained by removing the plug 32.
By lengthening fuzes such as described the powder chambers can be increased in
size if desired, the fuzes being still suitable for the service sockets.
In the modification represented in Figs. 16 and 17, an additional safeguard is
provided against the possibility of the dropping of the firing pin or striker when
unscrewing the cap or plate 19. In this case the steel pin or striker 8 is screwed
into a small cylinder 33 formed with a flange or projections 34 and with a hole and
female screw thread to receive the screw 21, so that when the said screw is removed
the firing pin or striker will still be securely held by the cylinder 33. Also the firing
pin is fitted with a collar 35 sunk into and bearing against the underside of the screw
plug 31, and the locking shoulders 36 sunk into a circular recess in the cylinder 7,
in order to leave more space in the ball chamber for the free movement of the balls.
In this arrangement also the spring carrying the knob 26 instead of being made to
surround the extension of the firing pin or striker as in the preceding arrangement,
may be formed with a bend or angular part that enters a recess in the plug 31.

page_text: Having now particularly described and ascertained the nature of the said invention,
and in what manner it is to be performed, I declare that I am aware balls have been
used for the purpose of preventing contact of the firing pin or striker with the
detonator, and therefore I do not claim broadly the use of balls for this purpose, but
what I do claim is :-
1. In a percussion fuze, providing a number of loose balls within a common chamber
in the fuze, the arrangement being such that the longitudinal movement of the firing
pin or striker, or of the detonator necessary to effect a discharge shall be prevented
by the said balls or some of them, except when they are by centrifugal force due to
rapid rotation of the projectile to which the fuze is applied thrown outward and caused
to assume an annular arrangement against the wall or circumference of the chamber
that contains them, thus leaving a central space sufficient to allow of the passage
of the cylinder or part that carries the pin or the detonator, as the case may be,
substantially as hereinabove described.
2. The improved percussion fuze substantially as hereinabove described with
reference to Figs. 1 to 5 inclusive of the drawings annexed.
3. The improved percussion fuze substantially as hereinabove described with
reference to Fig. 6 of the drawings annexed.
4. The improved percussion fuze substantially as hereinabove described with
reference to Figs. 7 to 15 inclusive of the drawings annexed or modified as described
with reference to Figs. 16 and 17.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.