IMPROVEMENTS IN FUZES
Year: 1884

page_text: I THORSTEN NORDENFELT of 53 Parliament Street in the City of Westminster
Civil Engineer do hereby declare the nature of my invention for "IMPROVEMENTS
IN FUZES" to be as follows:-
The object of my invention is to produce fuzes for use in all kinds of shell
projectiles which shall be more simple in construction more reliable in action and
safer in transport than the fuzes of many kinds now employed.
In most percussion fuzes hitherto adopted the parts which control the ignition
and at the proper time cause the fulminate to be struck consist of a hammer and a
mantlet. The latter is held in position to prevent the hammer from moving
forwards usually by means of a brass suspending wire or lead feathers or a cup
shaped support of thin brass or steel. On the discharge the fuze is "armed" by
the inertia of the mantlet shearing off the suspending wire or other support so
as to leave the hammer free to strike forwards on impact against the object
fired at.
I consider the support given to the mantlet by such brass wire, lead feather or
cup not to be as safe as might be, as during transport over rough roads and by
constant shaking the wire or lead may be worn away. The shell might then easily
be exploded so as to cause accidents more especially when it is not convenient to
have an additional safety pin to be drawn out before the projectile is put into the
gun.
In my improved fuze I support the mantlet by forming the hammer with a larger
diameter or shoulder at one end against which shoulder the mantlet rests and thus
holds the hammer in position-I make the mantlet of drawn brass or of other metal
having suitable elasticity and split or divide it on one side from end to end so that
pressure will cause the mantlet to open out sufficiently for its edge to pass the
shoulder on the hammer and glide over the entire length of the hammer and thus
leaving the bammer free to run forwards on impact. The elasticity of the mantlet
also ensures its adhesion to the hammer so that the stroke against the cap or
fulminate is given by the aggregate weight of the hammer and mantlet.
This fuze can be used in the point of the projectile as well as in its base in the
former case the flash passes through a hole in the hammer-in the latter case I have
one or more openings through the screwed cover of the fuze.
I can place the cap or detonating cap composition either in the hammer, in which
case a needle hard point is fixed in the cover-or I can place the cap or fulminate in

page_text: the cover and then the pointed hammer or a needle inserted into it strikes the cap
or composition.
By this method I also produce a very simple and effective time fuze which I can
easily combine with a percussion fuze.
When making a separate time fuze I place the hammer in front of the mantlet so
that on the discharge of the cartridge the inertia of the hammer overcomes the
resistance of the split mantlet and a blow is struck upon the fulminate with
sufficient energy to ignite it and the ignition passes to the usual fuze ring and
thence to the bursting charge. The time for the burst is regulated in the usual
manner by turning a moveable collar.
"
When making a combined percussion and time fuze I place the mantlet in front
of the hammer so that the fuze for percussion is "armed' on discharge by the split
mantlet gliding back over the thicker portion of the hammer.
Also at the moment of discharge the receding mantlet at or near the last part of
its rearward movement strikes and ignites a detonating composition which
communicates the flash through a circular channel and an orifice to the usual ring
fuze which is placed in a moveable collar. When the ring fuze has burnt until the
flame reaches the hole leading into the shell the bursting charge is exploded.
The moveable collar will of course be adjusted as usual for the ring fuze to burn
the required time for the range fired at.
The space between the bammer and the cover before the fuze is "armed " enables
me to put in a light spiral spring as sometimes used in other fuzes for holding the
hammer in position before impact to secure the full length of stroke.
The construction of the single fuze is simpler than that of my other fuze which
is arined on discharge and the combined percussion and time fuze is much simpler
than those generally used.
The safety of the fuze is gained by the fact that no shaking to which the fuze
may be exposed in transport however long continued can overcome the elasticity of
the mantlet or cause. it to move back the full length of the hammer without which
the fuze is not "armed."
It will also be found easier in manufacture on a large scale to secure the same
elasticity to split tubes than to apply suspending wires of very small dimensions so
as always to offer the same support to the mantlet.
•

page_text: I THORSTEN NORDENFELT of 53 Parliament Street in the City of Westminster
Civil Engineer do hereby declare the nature of my invention for "IMPROVEMENTS
IN FUZES "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 fuzes for use in all kinds of shell
projectiles which shall be more simple in construction more reliable in action and
safer in transport than the fuzes of many kinds now. employed.
In most percussion fuzes hitherto adopted the parts which control the ignition
and at the proper time cause the fulminate to be struck consist of a hammer and a
mantlet. The latter is held in position to prevent the hammer from moving
forwards usually by means of a brass suspending wire or lend feathers or a cup
shaped support of thin brass or steel. On the discharge the fuze is "armed" by
the inertia of the mantlet shearing off the suspending wire or other support so
as to leave the hammer free to strike forwards on impact against the object
fired at.
I consider the support given to the mantlet by such brass wire lead feather
or cup not to be as safe as might be as during transport over rough roads and
by constant shaking the wire or lead may be worn away. The shell might then
easily be exploded so as to cause accidents more especially when it is not convenient
to have an additional safety pin to be drawn out before the projectile is put into
the gun.
In my improved fuze I support the mantlet by forming the hammer with a
larger diameter or shoulder at one end against which shoulder the mantlet rests.
and thus holds the hammer in position. I make the mantlet of drawn brass or
of other metal having suitable elasticity and split or divide it on one side from
end to end so that pressure will cause the mantlet to open out sufficiently for its
edge to pass the shoulder on the hammer and glide over the entire length of the
hammer and thus leaving the hammer free to run forwards on impact. The
elasticity of the mantlet also ensures its adhesion to the hammer so that the stroke
against the cap or fulminate is given by the aggregate weight of the hammer and
mantlet.
This fuze can be used in the point of the projectile as well as in its base-in the
former case the flash passes through a hole in the hammer-in the latter case I have
one or more openings through the screwed cover of the fuze.
I can place the cap or detonating cap composition either in the hammer in which
case a needle hard point is fixed in the cover or I can place the cap or fulminate
in the cover and then the pointed hammer or a needle inserted into it strikes the
cap or composition.
By this method I also produce a very simple and effective time fuze which I can
easily combine with a percussion fuze.
When making a separate time fuze I place the hammer in front of the mantlet
so that on the discharge of the cartridge the inertia of the hammer overcomes the
resistance of the split mantlet and a blow is struck upon the fulminate with
sufficient energy to ignite it and the ignition passes to the usual fuze ring and
thence to the bursting charge. The time for the burst is regulated in the usual
manner by turning a moveable collar,

page_text: "
When making a combined percussion and time fuze I place the mantlet in front
of the hammer so that the fuze for percussion is "armed on discharge by the
split mantlet gliding back over the thicker portion of the hammer.
Also at the moment of discharge the receding mantlet at or near the last part of
its rearward movement strikes and ignites a detonating composition which
communicates the flash through a circular channel and an orifice to the usual ring
fuze which is placed in a moveable collar. When the ring fuze has burnt until
the flame reaches the hole leading into the shell the bursting charge is exploded.
The moveable collar will of course be adjusted as usual for the ring fuze to burn
the required time for the range fired at.
The space between the hammer and the cover before the fuze is "armed" enables
me to put in a light spiral spring as sometimes used in other fuzes for holding.
the hammer in position before impact to secure the full length of stroke.
The construction of the single fuze is simpler than that of any other fuze which
is armed on discharge and the combined percussion and time fuze is much simpler
than those generally used.
The safety of the fuze is gained by the fact that no shaking to which the fuze
may be exposed in transport however long continued can overcome the elasticity
of the mantlet or cause it to move back the full length of the hammer without
which the fuze is not "armed."
It will also be found easier in manufacture on a large scale to secure the same
elasticity to split tubes than to apply suspending wires of very small dimensions
so as always to offer the same support to the mantlet.
In order that my said invention may be most fully understood and readily
carried into effect I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figures 1 show an end view and also a vertical section of a percussion fuze
constructed in accordance with my invention and adapted to be screwed into the
base of a shell. A is the body of the fuze which enters and is screwed into the fuze
passage in the base of the shell. B is a hammer C is the mantlet and D is the $
cover. The cover when screwed into the body of the fuze keeps the hammer and
mantlet in place. D¹ D¹ are passages through the cover to permit the fire from the
fuze to pass to the charge. B' is the patch of fulminate upon the hammer and D*
is the pin upon the cover with which the fulminate is brought in contact at the
time of impact.
Figures 2 show the hammer to a larger scale, and
Figures 3 represent the mantlet to the same enlarged scale.
B
The hammer as will be seen has a conical surface upon it at B and the mantlet
has a corresponding surface at C. The mantlet is split from end to end at C² and
it may be grooved longitudinally at C³ C³ to adjust its elasticity. Its internal 4
diameter is such as to fit upon the upper end of the hammer but when the gun is
fired the inertia of the mantlet causes the hammer to be thrust into its interior,
⚫ the slit C³ in the mantlet opening to admit of this taking place.
When the forward movement of the shell is checked on its striking an object
then the momentum of the hammer and mantlet causes the patch of fulminate B¹
to strike against the pin D³ it explodes and the flash passes to the charge in the
shell.
Figures 4 represent a percussion fuze similar to that already described except
that a light spring E is here inserted to insure that the hammer shall remain in
place until the instant when the shell strikes.
Figures 5 represent a percussion fuze of like construction but adapted to be
screwed into the nose or forepart of a shell. The cover D in this case is without
perforations but a passage is bored through the hammer B and also through the
inner end of the body A. The hole in the hammer may be charged with priming

page_text: powder. The fulminate is exploded in the same way as before, it communicates
the fire to the priming powder and so to the charge within the shell.
Figure 6 is a side elevation. Figure 7 an end elevation and Figure 8 a vertical
section of a time fuze constructed in accordance with my invention. F F is the
body of the fuze adapted to be screwed into the nose or fore part of the projectile ;
it has also a a passage formed through it centrally and into this the piece G is
screwed. The parts F and G confine between them the ring H of which an under
side view is shown at Figure 9. This ring has a groove H' formed in it on its
under side passing nearly but not quite around the ring. The groove is filled with
time fuze composition such that if the composition be ignited at one end it will
take many seconds to burn out to the other end. The part F of the body also has
a passage F' bored in it which is charged with priming powder. The outer end of
this passage F coincides with the groove H¹ in which the fuze composition is.
contained.
The part G. receives within it the hammer B and mantlet C as before and these
parts are kept in place by the cover D.
In the manner already described when the shell is fired from the gun the
hammer enters the mantlet. At the same time the hammer strikes the patch of
fulminate at K and explodes it. The fire passes out by the apertures & Q' in
the piece G and by the passage H' in the ring H and so it reaches the commence-
ment of the fuze composition. The fuze composition commences to burn and it
continues to do so until the passage F' is reached when the priming powder therein
is fired and the bursting of the shell ensues. The ring H is capable of being
turned in the usual way to adjust the time between the firing of the shell from the
gun and the bursting which is done by placing a greater or less length of the fuze
composition in the groove H¹ between the point where the composition is ignited
in the passage H³ and the vent F¹ in the piece F by which the flame passes to the
charge.
The ring H is graduated externally to seconds and fractions of seconds to
facilitate adjustment Figure 10 is a vertical section of a combined time and
percussion fuze; it is similar in many of its features to the fuze last described.
In this case however it is the mantlet which by its inertia fires the fulminate by
which the fuse composition in the groove H¹ is ignited L L are caps containing
fulminate inserted into radial holes in the part G. These are struck by the
mantlet C when it slides on to the hammer at the time when the shell is fired
from the gun. The fire passes out by the passage H and ignites the composition
in the groove H. The fuze then operates as a time fuze in the manner already
described but if before the end of the time to which the fuze has been set the shell
should strike an object then immediately the momentum of the hammer and
mantlet B and C carry them forward, the patch of fulminate B' on the hammer
comes into contact with the pin D' on the cover the flash from the explosion passes
through the hole in the hammer to the charge and the shell bursts independently
of the time arranged.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :-
(1). The combination in a percussion fuze of a hammer and a split ring mantlet
in such manner that the mantlet retains the hammer and so ensures safety in
handling the shell whilst on firing from the gun the fuze is "armed" and on
impact is exploded by the continued forward movement of the hammer and mantlet
substantially as described.
(2). The combination in a time fuze of a hammer and a split ring mantlet in
such manner that the mantlet retains the hammer and so ensures safety in handling
the shell but allows the hammer to operate on the discharge of the projectile from
the gun substantially as described.

page_text: (3). The combination in a time and percussion fuze of a hammer and a split
ring mantlet in such manner that the mantlet retains the hammer until the
moment of the discharge of the projectile from the gun that then one of these
parts operates to ignite the time composition and on impact both operate to effect
the immediate ignition of the bursting charge substantially as described.
(4). My improved fuzes substantially as described and represented in the
annexed drawings.
Dated this 10th day of Novemba 1001