аци Igniting appa Charges without Danger from the Presence of Fire Damp.
Year: 1888

page_text: Safety-use
"
аци Igniting appa
Charges without Danger from the Presence of Fire Damp.
I, HERMAN MULLER, Manufacturer, of Clermont, in the kingdom of Belgium, do
hereby declare the nature of my invention to be as follows:-
My invention has for its object to prevent dangerous jets of flame and burning
gases at the time of igniting the safety fuse or during its combustion in the presence
of fire damp.
For this purpose the fuse (or slow match) is enveloped in wire gauze or
other metallic fabric which will prevent the passage of flame from the said fuse.
For igniting safety fuses I have designed a special instrument which allows the
fuse to be ignited at one of its extremities, while the fuse is placed in a tube of wire
gauze or other metal, and from which the gases of combustion may escape,
without producing outside a flame which would be capable of igniting the fire
damp.
When the fuse has been consumed for a length of a few centimetres, and the
combustion of the powder continues in the interior, the gases escaping at the extremity
can no longer offer any danger.
This instrument comprises a metallic tube or sleeve perforated at its upper end
and enclosing in the centre a thin tube the inner diameter of which is equal to the
diameter of the fuse. The upper part of the outer tube is surmounted by a metallic
cylinder of perforated sheet metal closed at both ends, one extremity being perforated
in the centre for the introduction of the fuse or wick and carrying the wick tube
which extends from the said extremity downward.
To the lower end of the outer tube or sleeve mentioned above and in immediate
proximity to the lower end of the safety fuse is secured an instrument for holding
and striking the explosive caps or pills which serve to ignite the safety fuse. The
spark produced by the detonation, and the burning gases emanating from the fuse
escape into the annular space left between the inner or wick-tube and the outer tube
or sleeve, and then pass through the perforated cylinder whereby their temperature
is reduced to such a degree, that they cannot ignite the fire damp.

page_text: When the fuse has burnt down to the upper end of the wick tube or of the sleeve, no
further sparks are produced, and there is no longer any danger. The apparatus is
now withdrawn from the fuse, so as to disengage the latter, which continues to burn
and thereby explodes the mine.
The instrument for igniting the fuse may be constructed as follows:-
Facing the lower end of the wick-tube and in the continuation of its axis, is
situated a sleeve, the head or upper end of which is screwed to the outer tube
surrounding the fuse, and has in the centre a flat horizontal recess or crosscut open
ou three sides.
In the said recess or crosscut is pivoted a horizontal movable lever, the total width
of which corresponds to the maximum height of a percussion cap. This lever has in
the centre a recess for the reception of the percussion cap.
The sleeve or tube of the detonating instrument encloses a spindle pointed at its
upper end and provided at the lower end with a knob situated outside the sleeve,
The middle part of the said spindle is surrounded by a helical spring resting at the
top against a collar formed on the spindle and at the lower end against a loose ring,
which may be fixed to the sleeve by means of a set screw.
The knob has a vertical arm guided in a slot formed in the lower end of the sleeve.
When using this instrument the knob with the spindle attached to it is pulled outwards
so as to compress the spring, after which the knob is turned sideways into a position
of rest, the percussion cap lever is turned outside, charged with a cap and then turned
back. The knob is now turned back into its original position and released,
whereupon the spring will throw the spindle against the percussion cap and
ignite it.
Unted this 4th dor of April 1888.
FAIRFAX & WETTER,
433, Strand, London,
Agents for the Applicant.

page_text: Safety-fuse and Igniting Apparatus for Setting Fire to Explosive.
Charges without Danger from the Presence of Fire Damp.
I, HERMAN MÜLLER, Manufacturer, of Clermont, in the Kingdom of Belgium, do
hereby declare the nature of my invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following.
statement:
Many attempts have been made, to invent an explosive, the products of which
will not ignite the firedamp or the dusty atmosphere of coal-mines.
This is not sufficient, because the ordinary safety-fuse or wick produces at the
time of its ignition, and often during its combustion, jets of flame and of burning
gases which are always dangerous in the presence of fire-damp.
To avoid these dangers, I surround the wick or slow-match with a single or double
envelope of wire gauze, or with other metallic fabric which prevents the passage of
flame from the said wick.
In the accompanying drawings Figs. 1 to 3 represent by way of example several
specimens of wick embodying my invention.
For igniting this wick or the ordinary wick, I have designed an instrument by
means of which one of the ends of the wick may be ignited, while the latter is
situated in a tube of sheet metal or of wire-gauze and from which the burning gases.
generated by the wick may escape without producing outside a flame capable of
igniting the firedamp.
When a few centimeters of the wick or fuse have burnt off, and the combustion of
the powder in the interior continues, the gases which escape from the extremity can
no longer offer any danger of ignition.
In the drawings Figs. 4, to 6, illustrate in axial section and side view an apparatus.
embodying my invention and combined with an instrument for igniting the wick. Into.
a metallic sleeve A, the upper part of which is perforated, is introduced a tube a
having an internal diameter equal to the diameter of the wick.
The upper part A' of the sleeve A, is surrounded by a cylinder B, the circum-
ferential surface of which is made of wire gauze or perforated metal and which is
closed by a screw cap b having in the centre an aperture 6¹, and to which the tube a
is fixed in such a manner, that the wick introduced through the opening may be
pushed down into the tube a until it arrives at the edge a¹, beyond which it cannot
go, as shown by the drawing.
At the extremity of the sleeve A and in close proximity to the end of the wick
and its powder core, is secured an instrument for holding and striking an explosive
cap or primer which serves to ignite the safety fuse. The drawing shows such an
instrument which will be described later.
It will be understood without further explanation, that the sparks produced by the
detonation, and the burning gases from the wick, will enter the chamber formed
by the sleeve A, that they will then pass through the perforations A¹ into the hood
or jacket B, and cool down to such a point that when escaping from this jacket, they
can no longer ignite the fire-damp.

page_text: As soon as the wick has been ignited and burnt down to the extremity of the
sleeve A, that is, of the tube a, it will no longer give off sparks and thus act as a
source of danger. The apparatus is now withdrawn from the wick, which continues
to burn with safety and finally causes the explosion of the mine.
The instrument for igniting the fuse or wick is constructed as follows:
A tube C is provided in front with a hollow extension (screwed to the extremity
of the sleeve A. In a recess c formed in this extension is pivoted a lever d, the total
width of which corresponds to the maximum height of a percussion cap.
This lever
has in the centre an aperture equal in diameter to the body of the percussion cap
and provided with an enlargement corresponding to the head of the said cap (see
Fig. 6). The tube C encloses a spindle H having at one end a percussion point, and
at the opposite end a knob g situated outside the tube C. The middle part of the
spindle is surrounded by a helical spring e resting at one end against a shoulder el
formed on the spindle, and secured at the opposite end to a ring f, movable around
The
the spindle H and which may be fixed to the tube by means of a set screw.
knob has a lateral extension which is guided in a groove ¹ formed in the corre-
sponding extremity of the tube C.
The instrument is used as follows:
By means of the knob the spindle H attached to it is pulled outward, and thereby
the spring e compressed. The spindle is then turned sideways until a tongue formed
on the extension / enters a shallow groove f¹ formed in the end of the tube C, and
rests therein while the lever is opened, charged with a percussion cap and turned
back again (see Fig. 5). Subsequently the knob g is turned in the opposite direction
until the tongue enters again the groove h¹, after which the knob is released,
thereby allowing the percussion spindle to strike the cap with the entire force stored
up in the spring.
This arrangement may, however, be replaced by Flobert's percussion apparatus or
any other which may be applied by any competent person. I may also vary the
method of igniting the fuse and employ for this purpose electricity, phosphorous,
tinder or any other known means.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. A fuse or slow match sheathed or enveloped with wire gauze or similar metallic
fabric, to prevent the flame or combustion from penetrating to the outside and igniting
the fire-damp or other explosive atmosphere.
2. An appliance for igniting fuses or wicks, chiefly comprising a metallic tube a
adapted to receive the said wick, one or more concentric casings made of wire gauze
or perforated metal, surrounding the said tube and an igniting instrument so connected
with the said casing or casings, that the extremity of the wick with the inflammable
(powder) core, when introduced into the wick tube, will be situated directly opposite
the igniting instrument, the whole arrangement serving to protect from ignition the
inflammable gases, or the dust contained in the atmosphere, and to cool the gases
of combustion before allowing them to mix with the surrounding air, substantially as
described.