Improvements in and Apparatus for Igniting Blasting Charges.
Year: 1893

page_text: Date of Application, 5th Dec., 1893
Complete Specification Left, 16th Feb., 1894-Accepted, 7th Apr., 1894
PROVISIONAL SPECIFICATION.
Improvements in and Apparatus for Igniting Blasting Charges.
I, CARL ROTH of Villa Roth, Hennickendorf in the Empire of Germany,
Chemist, do hereby declare the nature of this invention to be as follows:-
This invention relates to an improved process and apparatus "Roth's Flameless
Igniter," for igniting blasting charges without danger of producing explosions of
fire damp as hereinafter described.
The principle forming the basis of this invention can be applied in practice under
all conditions under which a slowly burning fuse has heretofore been employed for
The
igniting or firing a blasting cartridge or charge of explosive material.
advantage attending this improved method of firing the charge compared with
firing by means of an ordinary burning fuse is of great importance when the charge
has to be fired in a mine where fire damp is present. The danger which attends
the employment of a burning fuse under these conditions is by means of my
invention entirely obviated as all manipulations and apparatus involving the
production of a flame outside the hole are absolutely dispensed with.
According to my invention I cause certain gases or liquids to pass through a tube
or passage whereby they are brought into contact with substances or chemicals of
such a nature that by the action of the said gases or liquids upon the said substances
sufficient heat or a detonation is produced so as to bring about the explosion of the
cartridge or charge of blasting material. In like manner I employ the mechanical
pressure of a gas so that by compressing or exhausting the same certain fluids are
caused to pass into the interior of a specially constructed detonator where they are
brought in contact with substances which react upon them with the effect of
producing the required heat or detonation. The employment of a detonator
depends on whether the blasting powder or explosive employed is or is not of such
a nature as to admit of its being exploded by the direct action of the substances
hereinafter described in contact with the gaseous or liquid agents brought in contact
therewith. In case the gases or liquids are not by themselves capable of exploding
the mass in the detonator or blasting charge the detonator must be provided with
a substance which is heated sufficiently by the action of the materials introduced
and in this condition effects the explosive decomposition of the detonator which in
turn explodes the blasting charge.
The method of igniting herein before described in general terms may be carried
out in practice in various ways with regard to the nature of the materials employed
and to the mechanical devices provided (for the purpose of causing the said
materials or chemicals to react upon one another in the manner required) without
affecting the essential principle of the invention. I will now proceed to describe
by way of example arrangements by which my invention can be carried into effect
but I do not limit myself to the precise details of these examples. In order to
ignite a powerful explosive of the roburite dynamite or gun cotton types a detonator
primed with fulminate of mercury is provided the front end of which above the

page_text: fulminate is filled to about one third of the space above the fulminate with finely
pulverised dry peroxide of lead. This peroxide is in contact with the open end of
a thin lead, rubber or papier mache tube of sufficient length to ensure the safety
of the person firing the charge and communicating at its other extremity with a
gas generating apparatus. This apparatus is charged with dilute sulphuric acid
and hyposulphite of soda. When the outlet cock of this apparatus is opened
sulphurous acid is set free owing to the action of these two materials upon one
another. This acid is caused to pass through a washing vessel containing
concentrated sulphuric acid in order to completely deprive it of moisture. It then
drives out the air in the detonator through a small tube or passage provided in the
material employed for tamping the bore hole and causes the peroxide of lead to
become heated to incandescense in forming sulphate of lead thus producing the
explosion of the detonator which explosion is communicated to the charge of
explosive or blasting material.
According to another arrangement a glass bottle about half full of concentrated
hydrochloric acid is connected with pulverised metallic antimony in the cartridge
or detonator by a thin lead pipe (of from about 1 to 15 millimetres internal
diameter) passed through the cork and ending immediately under the lower end of
the cork or above the surface of the liquid. To explode the charge a ball or lump
of permanganate of potash or other salt capable of generating chlorine by acting
on a corresponding acid being coated with a suitably thick coating of oxide of zinc
or other passive or neutral substance is introduced into the bottle the cork and
flexible tube being afterwards replaced tightly in the mouth of the bottle. When
the hydrochloric acid and permanganate of potash or other equivalent substances
come in contact, chlorine is generated and passes through the lead pipe to the
metallic antimony and produces fire in the process of combining therewith to form
chloride of antimony. This operation has the result of exploding the detonator
and producing the explosion of the entire charge. In order to cause sufficient time
to clapse between the introduction of the lump into the bottle and the com-
mencement of the generation of chlorine to enable the operator to retire to a place
of safety it is necessary to provide the solid substance forming the said lump with
a covering or coating of suitable thickness of a substance such as zinc oxide for
example which dissolves in mineral acid without generating any objectionable
amount of gas. By these means the acid is prevented from liberating the chlorine
from the materials for a period corresponding with the time required to dissolve
the coating of the lump or proportionate to the thickness of the said coating.
This enables the explosion to be timed in the same way as with a time fuse (but
without the danger attending the use of the latter) this result being obtained with
the aid of a tube that need not project more than about 6 inches from the
bore hole.
In the same way as sulphurous acid and chlorine it is possible to employ in
accordance with my invention on the one hand hydrogen and on the other spongy
platinum or platinised asbestos and the gases required to ignite the several solid
or liquid substances employed may be stored ready for. use in gas holders or in a
compressed form being conveyed to the corresponding contents of the cartridges
by means of tubes of suitable length.
The following description is given as another example of a method of operating
according to my invention. In this case a bottle or leaden jar containing sulphuric
acid is employed. A lead tube of from about 1 to 15 millimetres internal diameter
projects into this bottle as far as the bottom the other extremity being placed in a
mixture of chlorate of potash and sugar in the cartridge placed in the interior of
the bore hole. When the charge consists of black powder no detonator is required.
The mixture of chlorate of potash and sugar is preferably in the form of a cinder
several millimetres thick imbedded in the powder. Now when a lump of
bicarbonate of soda or other carbonate is introduced into the vessel containing the
sulphuric acid and the cork tightly pressed in (or in case a cylinder .o: tube of
lead closed at the lower end) is substituted for the glass vessel the upper edges

page_text: of this cylinder, or tube are compressed by a circular tool around the small
ascending pipe so as to make an air tight joint) the carbonate is decomposed
and the carbonic acid generated drives the excess of sulphuric acid up the pipe
until it mixes with the chlorate of potash and sugar with the result of exploding
the charge. By regulating the pressure to which the lump is subjected or the
proportion of the active ingredient which it contains namely the carbonate to the
inert matter such as sulphates, kieselguhr, clay and the like the rate at which
the acid is forced up the tube can be controlled. By these means the explosion may
be timed to take place on the expiration of any desired period of time after the
introduction of the lump into the bottle.
When a gas previously prepared or generated is employed to produce the
explosion it is most convenient to use an air pump worked by hand or a bellows or
cylinder with compressed air or carbonic acid combined with a Woolf's bottle so
that when the gas enters the latter it causes the sulphuric acid contained therein
to ascend the tube communicating with the cartridge and to be discharged on to a
mixture placed in the end of the cartridge and capable of being ignited by the
action of the sulphuric acid.
The sulphuric acid may be caused to ascend the pipe leading to the inflammable
mixture of chlorate of potash and sugar or a mixture of chlorate of potash and
metallic antimony by an exhausting action produced by means of the air pump.
In this case the cap containing the said mixture or the case of the cartridge is
connected by an air tight joint with a tube leading to the air pump and with a tube
communicating with an open vessel containing the sulphuric acid. As the air is
pumped out of the cap or case containing the explosive materials the atmospheric
pressure causes the sulphuric acid or other liquid employed for the same purpose
to ascend the tube and come in contact with the said materials thereby producing
the required explosion.
The property of certain liquids of absorbing gases combined with the surface
attraction of solid bodies may also be utilised in carrying out my invention. With
this object a lead tube of from about 15 to 2 millimetres bore is filled with well
burned wood charcoal in minute pieces measuring say about 0-25 millimetres taking
care to allow as little time as possible to elapse between the burning and the
operation of placing the charcoal in the tube and the tube with its contents are
maintained for about half an hour at a temperature of about 200 degrees centigrade.
The pipe being wound in coils a stream of dry gaseous ammonia is caused to
pass through it and after cooling but whilst yet full of gas the two ends of the pipe
are tightly closed by pinching the sides together. When a tube thus prepared
having its contents protected from contact with the air and consequently capable
of retaining its properties for any length of time is employed for the purposes of
my invention it is opened at one end which is immediately connected by means of
a short rubber tube (capable of excluding the air) with a detonating cap containing
a mixture of chlorate of potash and sugar. The other end is likewise opened and
at the same tine immersed in concentrated sulphuric acid contained in an open
vessel. By the absorbing action of the gaseous ammonia and of the surfaces of
the pieces of charcoal the sulphuric acid contained in the said vessel is caused to
ascend the tube in the same way as it ascends under atmospheric pressure and pass
into the detonator where it comes in contact with the igniting mixture. The rate
at which the liquid ascends the tube can be regulated by packing the charcoal more
o tightly in the tube.
33
1
T
1
1000

page_text: Improvements in and Apparatus for Igniting Blasting Charges.
I CARL ROTH of Villa Roth, Hennickendorf in the Empire of Germany Chemist
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:-
-
My invention relates to an improved process and apparatus (which I term
"Roth's Flameless Igniter") for igniting blasting charges without danger of
producing explosions of fire damp as hereinafter described.
The principle forming the basis of my invention can be applied in practice under
all conditions under which a slowly burning fuse has heretofore been employed for
igniting, or firing a blasting cartridge or charge of explosive material. The
advantage attending my improved method of igniting or firing the charge as
compared with igniting or firing by means of an ordinary burning fuse is of great
importance when the charge has to be ignited or fired in a mine where fire damp is
present as the danger which attends the employment of a burning fuse under these
conditions is, by means of my invention, entirely obviated all mar,
pulations and
apparatus involving the production of a flame outside the hole bug absolutely
dispensed with.
My invention consists essentially in causing certain gases or liquids to move in
tubes or passages either by their own pressure or by pressure applied to them in
order to react either with the contents of a cartridge as such, or with a part of the
said cartridge constituting a detonator so as to produce ignition of the charge.
In carrying my invention into effect I may employ a gas or liquid so that by
compressing or exhausting it certain fluids are caused to pass into the interior of a
detonator where they are brought into contact with substances which react upon
them with the effect of producing the required heat or detonation ignition. The
employment of a detonator depends on whether the blasting powder or explosive
employed is, or is not, of such a nature as to admit of its being exploded with-or
without-the-generation-of-hent by the direct action of substances such as those
hereinafter described when brought into contact with the gaseous or liquid agents.
In case the gases or liquids are not by themselves capable of exploding the mass in
the detonator or blasting charge the detonator must be provided with a substance
which is either heated sufficiently by the action of the materials introduced or
which by this nation-will be decomposed or disintegrated by detonation without-the
generation of heat-and-in either-ease to effect the explosive decomposition ignition
of the detonator which in turn explodes the blasting charge.
The method of igniting hereinbefore described in general terms may be carried
out in practice in various ways with regard to the nature of the materials or
chemicals employed and to the mechanical devices provided (for the purpose of
causing the said materials or chemicals to react upon one another in the manne
required) without departing from the nature of my invention. I will now procee!
to describe by way of example arrangements by which my invention can be carrie.
into effect but I do not limit myself to the precise details of these examples provided
that the arrangements and materials employed be such as to cause ignition of the explosive
charge. In order to ignite a powerful explosive of the roburite, dynamite, or gun
cotton types a detonator D Figure 1 primed with fulminate of mercury F is provided
the front end of which detonator contains to say about one third of the space to
the rear of the fulminate finely pulverized dry peroxide of lead P which is against
or opposite the open end of a tube L which may be of thin lead, rubber, or papier-
maché and is of sufficient length to ensure the safety of the person firing the charge
the said tube communicating at its other extremity with a gas generating apparatus G.
This apparatus G is charged with diluté sulphuric acid and hyposulphite of soda.

page_text: When the outlet cock H of this apparatus G is opened sulphurous acid is set free
owing to the action of these two materials upon one another. This acid is caused
to pass through a washing vessel W containing concentrated sulphuric acid in order
to completely deprive it of moisture. It then drives out the air in the detonator
through a small tube or passage R which with the tube L passes through the
material employed for tamping the bore hole and causes the peroxide of lead to
become heated to incandescence in forming sulphate of lead thus producing the
explosion of the detonator which explosion is communicated to the charge of
explosive or blasting material.
According to another arrangement a bottle A Figure 2 (which bottle may be of
glass) say about half full of concentrated hydrochloric acid is connected with a
material which is inflammable when brought into contact with chlorine (such as
pulverised metallic antimony) in the cartridge or detonator by a thin lead pipe L
(of say from about 1 to 15 millimetres internal diameter) passed through the
cork K and terminating immediately under the lower end of the cork or
above the surface of the hydrochloric acid. To explode the charge a ball or
picce of permanganate of potash P, or other salt capable of generating chlorine
by acting on a corresponding acid is introduced into the bottle the cork K
and tube L being afterwards replaced tightly in the mouth of the bottle. When
the bydrochloric acid and permanganate of potash (or equivalent salt) come in
contact, chlorine is generated and this passes through the lead pipe L to the
metallic antimony and produces fire in the process of combining therewith to form
chloride of antimony. This operation has the result of exploding the detonator
and this causes the explosion of the entire charge. In order to cause sufficient
time to elapse, between the introduction of the ball or piece of the salt into the bottle
and the commencement of the generation of chlorine, to enable the operator to
retire to a place of safety it is necessary to provide the said ball or piece with a
covering or coating of a passive or neutral substance such as zinc oxide for
example which dissolves in mineral acid without generating any objectionable
amount of gas. By this means the acid is prevented from liberating the chlorine
from the materials for a period corresponding with the time required to dissolve
the coating of the said ball or piece and proportionate to the thickness of the said
coating. This enables the explosion to be timed in the same way as with a time
fuse (but without the danger attending the use of the latter) this result being
obtained with the aid of a tube that need not project more than about 6 inches
from the bore hole.
The vessel A Figure 2 may be advantageously replaced by a U shaped tube say
of lead and of 1 centimetre diameter having legs of say six centimetres long
(or the one leg may be slightly longer than the other) as shewn in Figure 3.
Into the open leg W of the vessel concentrated hydrochloric acid is introduced
and at the bottom or bend the tube is reduced as shewn to a diameter of say about
0.5 millimetre so that the acid will take a predetermined period (necessary to
enable the operator to get out of the way) to rise in the other leg and reach the
piece P of the salt say bleaching lime or permanganate of potash which is
supported on the contracted part of the leg as shewn. In this arrangement the
covering or coating of the said piece P with a neutral substance is unnecessary.
As soon as the acid reaches the piece P the gas given off is conducted by the
tube L to the detonator in the cartridge the said tube L being connected gas
tightly into the leg at Z and as the tube L communicates with the detonator, and.
this with a tube as at DR Figure. 1 when gas is generated at P it passes to the
detonator without causing back pressure sufficient to expel the liquid from the
leg W.
In place of sulphurous acid and chlorine there can be employed in accordance
with my invention hydrogen on the one hand and on the other hand spongy
platinum or platinised asbestos and the gases, required to ignite the solid or liquid
substances employed, may be stored ready for use in gas holders or in a compressed

page_text: form and conveyed to the corresponding contents of the cartridges or detonators
by means of tubes of suitable length.
Gases compressed and stored up in this manner may also be used when instead
of a single cartridge a number of cartridges are to be exploded simultaneously.
In this case a Woolf's bottle having as many outlet tubes.or passages as there are
cartridges to be simultaneously exploded, is connected by means of a single main
pipe or tube with the gas holder. A pipe X (Figure 4) say of about 3 centimetres
internal diameter and having as many branches Y attached to it as there are
cartridges to be simultaneously fired may be employed with the same effect.
these branches Y the individual tubes which conduct the gas to the cartridges are
connected by means of gas-tight joints. The gas from the holder is conducted to
the main pipe X by a single pipe Z the said gas being reduced to the required
pressure by means of a reducing valve V arranged in the desired position on the
.holder.
With
The following is another example of a method of operating according to my
invention. In this case a bottle or leaden jar A (Figure 5) containing sulphuric
acid is employed. A lead tube L of from say about 1 millimetre to 1-5 millimetres
internal diameter projects to the bottom or near to the bottom of this bottle the
other extremity being placed in a mixture of chlorate of potash and sugar in the
cartridge placed in the interior of the bore hole. When the charge consists of
black powder or any other blasting material which can be ignited by an ordinary
flame no detonator is required. The mixture of chlorate of potash and sugar is
preferably in the form of a cylinder several millimetres thick embedded in the
powder. When a piece of bicarbonate of soda P² or other carbonate is
introduced into the vessel A containing the sulphuric acid, and the cork K is
tightly pressed in (or in case a cylinder or tube of lead closed at the lower end
is substituted for the glass vessel, when the upper edges of this cylinder, or tube
are compressed around the small ascending pipe so as to make an air tight joint)
the carbonate is decomposed and the carbonic acid generated drives the excess of
sulphuric acid up and along the tube L until it mixes with the chlorate of potash
and sugar with the result of exploding the charge. By regulating the pressure to
which the piece of bicarbonate is subjected or by proportioning the active
ingredient (the carbonate) to inert matter such as sulphates kieselgühr kieselguhr,
clay or the like, the rate at which the acid is forced up and along the tube can be
controlled. By these means the explosion may be timed to take place on the
expiration of any desired period of time after the introduction of the aforesaid
picce into the bottle.
When a gas previously prepared or generated is employed to produce the
explosion it is most convenient to use an air pump S (Figure 6) worked by hand
or a bellows (or a cylinder with compressed air or carbonic acid) and combined
with a Woolf's bottle B so that when the gas enters the said bottle it causes the
sulphuric acid contained therein to ascend and pass along the tube L com-
municating with the cartridge and to be discharged onto a mixture placed in
the end of the cartridge and capable of being ignited by the action of the
sulphuric acid.
The sulphuric acid may be caused to ascend and pass along the tube L leading
to the inflammable mixture (such as one of chlorate of potash and sugar or a
mixture of chlorate of potash and metallic antimony) by an exhausting action
produced by means of the air pump S (Figure 7). In this case the cap containing
the said mixture or the case of the cartridge is connected by an air tight joint
with a tube a leading to the air pump S and with the tube L communicating with
an open vessel B' containing the sulphuric acid. As the air is pumped out of the
cap or case containing the explosive materials the atmospheric pressure causes the
sulphuric acid (or other liquid employed for the same purpose) to ascend and pass
along the tube L and come into contact with the said materials thereby producing
the required explosion.

page_text: It is evident from the description of my invention that in place of the materials.
hereiubefore mentioned which produce the desired action inside the cartridge or
casing any other suitable materials may be used which ignite and explode when in
contact with the gas or liquid introduced or cause the ignition and explosion of
another material. For example chlorate of potash may be replaced by any
other substance, which reacts in the presence of a combustible substance with.
sulphuric acid and results in the evolution of sufficient heat to cause ignition and
explosion. Sugar or metallic antimony can also be replaced by other substances
which react with oxygen and chlorine respectively giving off heat sufficient to cause
ignition or explosion; for instance in conformity with the principle of my invention
oxygen may be admitted into a detonator the front end of which contains platinum
black moistened with alcohol. The admission of concentrated nitric acid into a.
detonator case wholly or partly filled with sodium will also have the desired effect.
The property of certain liquids of absorbing gases combined with the surface
attraction of solid bodies may also be utilised in carrying out my invention.
With.
this object a lead tube of from about 15 to 2 millimetres bore is filled with well
burned wood charcoal in minute pieces measuring say about 0.25 millimetre taking.
care to allow as little time as possible to elapse between the burning and the
operation of placing the charcoal in the tube and the tube and its contents are
maintained for about half an hour at a temperature of about 200 degrees centi-
grade. The pipe being wound in coils a stream of dry gaseous ammonia is cause.
to pass through it and, after cooling, but whilst yet full of gas, the two ends of the-
pipe are tightly closed by pinching the sides together. When a tube thus prepared
having its contents protected from contact with the air and consequently capable-
of retaining its properties for any length of time is employed for the purposes of my
invention it is opened at one end which is immediately connected by means of
a short rubber tube (capable of excluding the air) with a detonating cap containing
a mixture of chlorate of potash and sugar. The other end is likewise opened and
at the same time immersed in concentrated sulphuric acid contained in an open.
vessel. By the absorbing action of the gaseous ammonia and of the surfaces of the
pieces of charcoal the sulphuric acid contained in the said vessel is caused to ascend
and pass along the tube (in the same way as it ascends and passes along under-
atmospheric pressure) and pass into the detonator where it comes in contact with
the igniting mixture. The rate at which the liquid ascends and passes along the
tube can be regulated by packing the charcoal more or less tightly in the tube.
I am aware that it has been before proposed to expand a charge of lime by means of u
liquid and I make no claim to such a mode of expansion.
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. Igniting blasting charges by causing gases or liquids to pass along conduits.
under the direct or indirect action of pressure, exhaust, attraction or absorption
(produced either mechanically or chemically) and to come into contact with
substances which are already themselves blasting agents or which by the influence
of the said-action become blasting agents or which are employed in addition to the
explosive or blasting charge or detonator for the purpose of reacting with the said
gases or liquids to cause an ignition and explosion (with or without the generation
of heat) of the blasting charge substantially as hereinbefore explained.
2. Means for igniting blasting charges consisting of the combination in or with.
the charge of substances such for example as peroxide of lead, spongy platinum.
platinised asbestos, metallic antimony or sodium or mixtures of chlorate of potash.
and sugar or antimony and means for passing into contact therewith from the outside.
gases (such for example as sulphurous acid hydrogen, oxygen, or chlorine or gases
capable of a similar action) or liquids (such for example as concentrated sulphuric
acid or concentrated nitric acid or liquids capable of a similar action) so as to.

page_text: cause ignition combustion or detonation of the explosive charge substantially
as hereinbefore described.
3. Means or apparatus arranged substantially as hereinbefore described and
illustrated under several examples in the accompanying drawings for the purpose
described.
JOHNSONS & WILLCOX.