Improvements in and relating to the Use of Electricity as a Source of Explosive Power.
Year: 1887

page_text: Date of Application, 14th Nov., 1887
Complete Specification Left, 4th Aug., 1888
Complete Specification Accepted, 21st Sept., 1888
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Use of Electricity as a Source
of Explosive Power.
SAMUEL JOYCE Junr. Electrician, 113 Richmond Road, Dalston, London. I do
hereby declare the nature of this invention to be as follows:-
-
The Electric Explosive consists of a vessel of any suitable material, such as glass or
metal, wholly or partially filled with water, which is heated by the passage of an
electric current through a coil of wire inserted in it; thus steam is generated and the
vessel exploded when sufficient pressure has been attained. Or the before-mentioned
vessel may be wholly or partially filled with some decomposable liquid, such as dilute
sulphuric acid, which liquid is decomposed by passing through it an electric current
by means of two electrodes inserted in it. The mixed gases thus obtained are then
caused to re-unite by the passage of an electric spark, thus producing an explosion.
Dated this 12th day of November 1887.
SAMUEL JOYCE, JUNR.

page_text: Improvements in and relating to the Use of Electricity as a Source
of Explosive Power.
SAMUEL JOYCE Junr. of 113 Richmond Road, Dalston, Electrical Engineer. I 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:
This invention consists;-In the utilization, as an explosive agent, of the pressure
and expansive force of steam, or other vapour; and of water, or other liquid, in a
closed shell, heated by the passage of an electric current through a wire, or wires,
inserted in it.
And of apparatus, such as tamping arrangements to be used therewith.
22
The steam shell consists as shown, in elevation and plan, in figures 1 & 2, of an
outer case A of thin metal, or other material, of such thickness as to burst at or near
a fixed pressure, having screwed in at one end an insulating bung B, which may be of
ebonite or any other suitable insulator of electricity. This bung B is "backed up
by the nut D, as shown, to prevent its expulsion when the pressure rises. Through
this bung are inserted screwed conductors C. C. preferably of copper, having the
steam-tight heads N, as shown, so as to produce steam-tight joints with the bung B." The
conductors or terminals C. C. are connected inside the shell A by a length of wire W,
or by lengths of wire in parallel, which may be cotton or silk covered, coated with paraffin
wax or other suitable insulator, to prevent their making contacts one with another
at points along their lengths; and to protect them from corrosion by the water, or
other liquid in the shell. These wires may be of metal, or carbon, and are preferably
of high specific resistance. The diameter, if circular, or sectional area if flat; the
length; and the electrical resistance of the wire or wires may be varied to suit the
shape and power of the shells, or the mode of electrical distribution at the place where
they are to be used. The quantity of water, or other liquid, in the shell may be varied
to suit the explosive power required, it being found that when the liquid is small in
quantity the explosion is less powerful than when the shell is nearly full. Thus, by
varying the quantity of liquid in a shell the explosive power of it may be varied while
the size and bursting pressure remain unaltered. The shell A may be made of various
metals, or materials, of various thicknesses having different tensile strengths so as to
permit of the explosion taking place at various pressures. Or the shell may be
constructed of metals of various melting points so that the explosion shall take place
owing to the weakening of the metal as the temperature due to the pressure approaches
the melting point of the particular metal used.
Or the shell may be made, as shown in Figure 3 in which A is a tube of metal, or
other material, too stout for explosion by the pressure allowed for, having the

page_text: insulating bung B with the conductors C. C. passing through it, as here-in-before
described, the case A being spun over it, as shown, to prevent its expulsion. The
conductors C. C. are connected to two or more wires W the other ends of which are
connected by two rods or conductors F. F. fixed into, and electrically connected
with, the bung D which is of lead or some fusible alloy. The action of this shell is
that, when explosion occurs due to the melting or weakening of the bung D, the
circuit between the wires or terminals C. C. is broken; either by the wires becoming
torn by the pull on them when the rods F F are blown out; or by the disconnection
of one or both of the wires from the rods F. F. or from the bung D. The main part
of this shell, viz.; the case A with the insulating bung B and conductors C. C. may be
used again, if uninjured by the explosion.
"
22
Or the shell may be constructed on the plan shown in figure 4 in which A is the
outer case consisting of a tube, which may be solid-drawn or formed of sheet metal, as
tinned iron, rolled into a tube of the required diameter and having a sean made steam-
tight with solder. The end marked E is spun over so as to form a neck or
shoulder. The conductors C. C. are screwed and fitted into a disk of insulating
material H and passed in from the end K; the space B is then packed or filled with
Plaster of Paris, Portland, Roman or other cement as may be convenient. The end K
is then closed with a lid, soldered in, as shown.
"spun
"
Or a shell may be made as shown in figure 8 in which A is the outer case
over, as shown, and forced into the under side of the head of the bung B by the nut O,
thus forming a steam-tight joint. The bung B is of ebonite or other suitable insulator
of electricity and has the conductors C. C. as here-in-before described.
Or a ball-cartridge may be constructed, for use in a suitable gun, as shown in
figure 5 where the case A, with insulating bung B, terminals or conductors C. C. and
wires Wall as hereinbefore described, are fitted to a projectile P, as shown. For
the projectile P may be substituted a charge of dynamite, or other explosive, fitted
with its own separate detonator or fuse.
Or a shell may be made as shown in figure 7 in which A is a tube of flexible
material, such as Indian rubber, fixed to the metal bung E and to the insulating
bung B. These two bungs are fixed together by the rod which is covered by the
insulating tube G, as shown. The bung B is provided with the conductors C. C,
steam-tight heads N. N. and wire W as hereinbefore described. This shell is filled
full, or nearly full, of water or other liquid, and when the current is passed through
the wire W, the liquid grows hot and expands, exerting a great pressure on the bore-
hole into which the shell is placed, thus causing a fissure of the coal or other material,
and allowing the elastic tube to burst, the fragments of coal &c. being dislodged by
the expansion of the vapour given off by the hot liquid. Or, for the flexible case A as
described, a case of ductile metal, as lead, may be substituted. Or, for the flexible
case A as described, a corrugated or fluted metal case may be substituted, constructed
in such a way as to unfold or expand when the pressure rises.
Or the bore-hole itself may be used instead of the outer shell, and a combination
tamping and heating arrangement may be used. Such apparatus is shown in figure 10
in which T is a tube of strong metal, such as steel, having recesses cut in it to admit
of the levers L. L being pivotted therein on the centres as shown at P. P. These
levers may be two or more in number as is convenient. Into the tube T slides the
tube D having a head, as shown at H, fitted with the insulating bung B, with
conductors C. C. as hereinbefore described. Between the end of the tube T and the
head H is a piece of elastic tubing R which may be Indian rubber. The tube D has
recesses cut in it, corresponding with the recesses in the tube T, and bevelled in such
a way, as shown, so as to ongage with the inside ends of the levers L. L. The other
end of the tube D is screwed, and fitted with the nut N on turning which the tube D
(being provided with pegs to prevent its rotation) is drawn into the tube T, thus
raising the levers L. L. and causing their points to project above the surface of the
tube T and compressing the elastic tube R longitudinally so as to expand it
diametrically. The conductors C. C., which may be screwed or otherwise fastened in,
are connected with the before described wire at their ends marked C. C.; and to the

page_text: other ends X. X. are connected the leads, from the source of electricity, which pass
out through the tube D. This combined tamping and beating arrangement works in
the following manner. The bore-hole being filled with water, or other liquid, the
apparatus is inserted, the end H being introduced first or inwards. Then the nut N
is turned and the elastic tube expands as before described in such a way as to make a
tight joint in the bore-hole at R. At the same time the levers L. L. rise and are
forced into the coal or other material, thus completely preventing the expulsion of the
apparatus for, the levers L. L., being free to move upwards, the greater the
expulsive pressure, the more they are forced upwards and into the coal. Or, in this
apparatus, the head H may be fitted with a case containing the water or other liquid,
such case may be similar to any of those hereinbefore described.
Any possible combinations of these different moles of construction shown in
figures 1 & 2, 3, 4, 5, 7 & 8 may be used. Thus the cement plug or bung shown in
figure 4 at B, may be substituted for the bungs respectively illustrated and described
in figures 1 & 2, 3, 5, and 8. Or the backing up nut D shown in figures 1 & 2 may
be used instead of the "spinning" over of the case A as described in figures 3 & 5.
Or the systein of construction shown in figure 8 may be substituted for that shown
in figures 1 & 2, 3 & 5.
"
23
Having now described the steam explosive and modes of constructing shells or
cartridges, both ball and blank, it remains to show the manner of application of this
invention and the mode of supplying a separate shell, or a number of shells, with the
necessary energy in the shape of an electric current. The shell having had suitable
cables or leads connected to it, is placed in the bore-hole and tightly tamped therein
as may be required. Or in the case of the shell shown in figures 7 & 10 no tamping
may be necessary. Then connection with the source of electricity is made, through
some form of switch hereinafter described. In the case of more than one shell being
fired at one and the same time, they are all connected together electrically,
either in parallel or in series, and are joined, through the switch hereinafter described,
to the source of electricity. The current may be generated, on a small scale by a
primary battery, or, on a large scale by a Dynamo actuated by a steam-engine or
other prime-mover. In the latter case the mains may be run down the mine, or
other scene of action; or the current may be stored in accumulators or Storage
Batteries. Such battery may be placed on a trolly and run from place to place as
may be required. When the current is to be used in a mine, or other place where
fire-damp or other explosive mixture may be, all electrical connections must be made
with, and by the aid of the switch above mentioned and now fully described. This
switch is automatic or otherwise, is enclosed in an air-tight case, and has the handle
passing through a stuffing box, thus preventing the communication, of the sparks
produced on making, or breaking, circuit, with the outside air. Also the whole
battery may be provided with an air-tight cover for the same purpose; and also to
prevent the escape of any objectionable gases which may be given off. In cases
where connections are necessary at promiscuous places along the mains, to the battery or
otherwise, they may be made with the aid of the connector shown in figure 6 where L
is a terminal or clamp which may be connected to any part of the circuit. The other
end of L forms a socket S into which fits the plug Q provided with a similar clamp R.
This plug and socket are coupled together by, and inside of, the flexible bulb I which
may be of Indian rubber or other close textured, flexible material and which is of
such size as to admit of the plug hanging quite free from the socket S while
connection is being made with R. & L. Thus, owing to the flexibility of the bulb I,
Q can be forced into S and connection made, or broken, without any danger arising
from the spark at any time produced. Or, for the flexible bulb in the figure may be
substituted a telescopic system of tubes forming a case over the plug and socket and
capable of being lengthened to admit of the withdrawing of the plug from the
socket. This is shown in figure 9 in which the clamp L with the socket S is joined
to the clamp R & plug Q by the telescopic tubes X & Y which are insulated from L
and R as shown at Z. Z. Packing may be placed in the space M to prevent the
communication of sparks produced at S and with the outside air.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I hereby state that
I do not limit myself to the precise construction of shells as shown in the
figures for the better illustration of the descriptions given; but that what I
claim is :-
(1) The use of a shell or cartridge, substantially as described and shown in
figures 1 & 2, 3, 4 5, 7, 8 & 10, which, on being supplied with a current of
electricity becomes explosive in proportion to the power supplied to it by the electric
current.
(2) The use of a shell or cartridge substantially as described and shown in figure 7
for the purpose of producing a pressure on the bore-hole due to the expansion of the
liquid when heated by a current of electricity as particularly described.
(3) The use of a shell or cartridge as substantially described, combined with the
tamping arrangement as substantially described and shown in figure 10.
(4) The use of the compound tamping and heating arrangement shown in figure 10,
for the purpose substantially as described.
(5) The use of the ball-cartridge substantially as described and shown in
figure 5.
(6) The use of cartridge shown in figure 5 having substituted for the projectile as
shown a charge of dynamite or other explosive fitted with its separate detonator or
fuse, substantially as described.
(7) The use of the construction of shell as shown in figure 3 for the purpose
of automatically breaking circuit at the moment of explosion, substantially as
described.
In witness of the above, I, the said Samuel Joyce have hereunto set my hand
and seal the 4th day of August 1888.
SAMUEL JOYCE, JUNR.