Improvements in Electric Firing Apparatus for Ordnance.
Year: 1897

page_text: Date of Application, 20th Oct., 1897
Complete Specification Left, 20th July, 1898-Accepted, 20th Dec., 1898
PROVISIONAL SPECIFICATION.
Improvements in Electric Firing Apparatus for Ordnance.
We, VICKERS SONS & Co. LIMITED, of River Don Works, Sheffield, in the
County of York, Steel Manufacturers, ARTHUR TREVOR DAWSON, of 28, Victoria
Street, Westminster, London, Superintendent of Ordnance Works, and GEORGE
THOMAS BUCKHAM, of 28, Victoria Street, Westminster aforesaid, Engineer, do
hereby declare the nature of this invention to be as follows:-
Our invention relates to electric firing apparatus for ordnance so arranged that
firing is automatically prevented unless the gun is in firing position, and that
electrical contact for firing cannot take place accidentally. In order to prevent
firing when the gun is not in firing position, we introduce in the electric circuit
a switch, which is normally kept by a weight or spring from completing the
circuit, but, which, when the gun is run out to firing position, has a slide or
pivotted arm acted on by a tappet on the gun, so as to make contact, closing the
circuit, in condition to pass the firing current. This current is transmitted from
the source of electricity by the action of a firing switch which is in the form of
a pistol that can be held in the hand.
In the case of the pistol there is a loaded lever attached to the trigger, and
having on its unloaded arm an insulated piece of conducting metal, which is
pressed by a spring plunger, co-operating with the load on the other arm of the
lever, away from a contact stud. One of the conducting wires being connected
to the spring plunger and the other to the contact stud, on pulling the trigger in
opposition to the weight and spring, the piece of metal is brought to bear on the
stud thus forming a conducting bridge connecting the plunger and stud and thus
closing the electric circuit.
Dated this 20th day of October 1807
Improvements in Electric Firing Apparatus for Ordnance.
We, VICKERS SONS & Co. LIMITED, of River Don Works, Sheffield, in the
County of York, Steel Manufacturers, ARTHUR TREVOR DAWSON, of 28, Victoria
Street, Westminster, London, Superintendent of Ordnance Works, and GEORGE
THOMAS BUCKHAM, of 28, Victoria Street, Westminster aforesaid, Engineer, 'do
Price R71

page_text: 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 follow-
ing statement;
Our invention relates to electric firing apparatus for ordnance so arranged that
firing is automatically prevented unless the gun is in the firing position, and that
electrical contact for firing cannot take place accidentally. In order to prevent
firing when the gun is not in the firing position, we introduce in the electric circuit
a switch which is kept by a spring from completing the circuit, but which when
the gun is run out to firing position, is moved so as to make contacts, closing
the circuit.
The current is transmitted from the source of electricity by the action of a
firing switch which is in the form of a pistol, suitable to be held by hand. In
the case of the pistol there is a loaded lever attached to the trigger, and having
on its unloaded arm an insulated piece of conducting metal which is pressed by a
spring plunger, co-operating with the load on the other arm of the lever, away
from a contact stud.
One of the conducting wires being connected to the spring plunger, and the
other to the contact stud, on pulling the trigger, in opposition to the weight and
spring, the piece of metal is brought to bear on the stud, thus forming a con-
ducting bridge connecting the plunger and stud, and closing the electric circuit.
In order that the construction and action of the apparatus may be more clearly
understood we shall describe it in detail referring to the accompanying drawings.
Figure 1 is a vertical section and Figure 2 is a sectional plan of the firing
pistol. Figure 3 is a vertical section, and Figure 4 is a sectional plan of the
switch which is shewn in its two different positions in Figures 5 and 6.
A is the hollow pistol case in which is pivotted a lever having a heavy rear
arm B, a trigger arm B and a third arm B2 on the underside of which is fixed
an insulated plate of metal. One of the conducting wires W is attached to a
spring urged plunger Con which rests the lever arm B2, the other wire W' is
attached to a piece of metal C: C2 is a block of insulating material in which the
metallic piece C' is held and in which the spring plunger C is fitted to slide.
A bracket D¹ fixed on the cradle D in which the gun slides is made with side
recesses into which the casing E of the switch is fitted and held in position by a
spring bolt E. Within the casing is fitted to revolve a plug F having two opposite
segments made of insulating material and a hole through it also lined with insu-
lating material. Through this hole and the segments, passes a rod of metal G
secured by nuts on its ends. The plug F has an arm F which terminates in a
projecting pin F2 and on the axis of the plug is a spring F3 which urges the plug
against a stop to the position shewn in Figure 6. The two conducting wires Wi
and W2 are connected to spring plungers which bear against the plug F on opposite
sides of it. R is the breech ring of the gun between which and the cradle D the
pin F projects. When the gun has recoiled, the breech ring R, being at some
distance behind the cradle D as shewn in Figure 6, the pin F3 being free, the
switch plug F is urged by its spring to take the position in which the ends of the
rod are not in contact with the spring plungers (Figure 6). But when the
gun is run out to firing position bringing its ring R nearly up to the cradle, as
shewn in Figure 5, then the pin F and arm F¹ are moved so as to turn the plug F
into the position when the ends of the rod G are in contact with the spring
plungers, so that there is a conducting connection of the wire W to the wire W2
When the parts are in this condition, and the wire W is in connection with a
source of electricity, while the wire We is in connection with the firing fuse, the
gun can be fired by pulling the trigger B¹ thus bringing the plate on the arm B
down on the piece of metal C¹ so as to form a conducting bridge from the wire W
through the plunger C to the piece C¹ and the wire W When the recoils.
gun
the switch plug F is urged by the spring to take the position shewn in Figure 6
opening the circuit, so that the gun cannot be fired electrically until the gun is

page_text: again run up to firing position. When the trigger B₁ is let go, the heavy arm B
and the spring plunger C cause the plate on the arm B2 to leave the piece C¹ thus
opening the circuit until the trigger is pulled again.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed, we declare that what
we claim is:-
1. Safety electrical firing apparatus for ordnance consisting of a switch in form
of a pistol held in the hand, and a switch on the gun cradle closing circuit only
when the gun is in firing position wires connecting a source of electricity to the
pistol, the switch and the firing fuse, substantially as described.
2. The firing pistol comprising a spring plunger, a trigger lever having an arm
adapted to form a conducting bridge between pieces of metal, connected respectively
to a source of electricity and to the switch on the gun cradle, substantially as
described.
3. The rotating switch on the gun cradle comprising a spring and lever arm
having a pin in the path of the breech ring of the gun, substantially as described.
Dated this 20th day of July 1898.
ABEL & IMRAY,
Agents for the Applicants.