Improvements relating to the Firing of Blasting Charges in Mining and other Operations and to Means therefor.
Year: 1886

page_text: Date of Application, 10th Dec., 1886
Complete Left, 8th Sept., 1887
Complete Accepted, 28th Oct., 1887
Improvements relating to the Firing of Blasting Charges in Mining
and other Operations and to Means therefor.
I, JOHANN LAUER of Vienna in the Empire of Austria, Lieutenant Colonel in the
Corps of Engineers, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improved means for firing the blasting charges used in
mining and similar operations.
According to the said invention charges of mining powder or dynamite instead of
being fired by match cords or electricity as heretofore, are fired by means of friction
fuzes of similar construction to the friction priming-tubes commonly used for firing
ordnance.
The outer shell of each fuze consists of a tube of metal, wood, mill-board or other
suitable material and has a length corresponding to the depth of the bore hole. Near
one end of the said tube is inserted a quantity of priming composition preferably in
the form of a pellet, through which passes a wire projecting outwards from the other
end of the tube. The outwardly extending end of the said wire on one side of the
pellet is formed into a loop or eye, and its short end, on the opposite side of the
primary pellet, is flattened and provided with toothed edges.
The end of the fuze, near which the priming pellet is fixed is tightly closed by
means of a plug of wax, pitch or other suitable material.
In fuzes intended for firing powder charges the space between the priming com-
position and the said plug is filled with powder, while in fuzes for firing dynamite
this space contains a large copper-cap filled with fulminate and held in place by a
tuft of wool or cotton interposed between the cap and the said flattened end of the
wire.
After the charge has been introduced into the bore hole a fuze is inserted close to
the side of the said hole which is then tamped with clay. Before inserting a
dynamite fuze into a hole, the said fuze has a small dynamite cartridge fixed to its
front end.

page_text: When several charges are to be fired simultaneously they are first connected by
pairs, by means of cords, wires, chains, ropes or other similar means having each end
fixed to the wire loop of a fuze. Then each two of these primary cords are connected
by secondary cords, having their ends formed into or provided with loops or eyes or
spring hooks, which are freely movable along the primary cords. In the same
manner, two secondary cords may be connected by a tertiary cord, to which the
firing-cord proper, which may be, say, 60 feet long, is attached by means of a freely
movable spring hook.
By this arrangement it is made possible to stretch all the cords of the system by
drawing backward the firing-cord. As soon as the cords are stretched a sudden pull
of the firing cord will cause the wires of all the fuzes to pass through the priming
pellets, and thus fire the charges.
Dated this 10th day of December 1986
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.

page_text: Improvements relating to the Firing of Blasting Charges in Mining
and other Operations and to Means therefor.
I, JOHANN LAUER, of Vienna, in the Empire of Austria, Lieutenant-Colonel in the
Corps of Engineers 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 improved means for firing the blasting charges used in
mining and similar operations. According to the said invention blasting charges
instead of being fired by means of match cords or by electricity as heretofore, are
fired by means of friction priming tubes which are set in action in the known manner
by a firing cord. In order to enable the friction wires of several priming tubes
inserted in the blasting cartridges to be partially torn out at the same time the loops
of two adjoining wires according to the said invention, are first connected by a wire,
cord or the like, then every two such primary cords by a secondary cord, the terminal
loops of which can be freely displaced upon the primary cords, until finally, on the
last connecting cord is displaceably fastened the loop arranged at the front end of the
firing cord. This arrangement permits of all the cords fastened to the loops of
the friction wires being stretched simultaneously. The cords can be replaced by
chains or wire ropes if desired.
In the accompanying drawing
Figure 1 represents a friction fuze for blasting powder, constructed according to
the present invention.
Figure 2 shows such a fuze as used for dynamite.
Figure 3 shows a bore hole charged with powder.
Figure 4 shows a bore hole charged with dynamite; and
Figure 5 is a diagram illustrating the arrangement of the firing cord:
b
The outer casings of the friction fuzes are composed of a small metal, wood or
pasteboard tube a, the length of which must correspond to the greatest depth of the
bore hole. This small tube contains near the front end the priming 6 through which
passes the friction wire c, and enclosed in a narrow tube 6 or in any other casing
filling up the small tube a. The friction wire c is provided in front of the priming b
with a flattened and toothed part c¹, and behind the priming bit extends to the
outside to the small tube a in order to form on the outside thereof an eye or loop c*
for inserting the firing cord. In the fuze Figure 1 for firing blasting powder the
foremost end of the tube a contains as usual a bouncing charge e of gun powder, in
front of which and in the end of the tube a is fixed a plug of pitch, wax or other
suitable material.
The friction fuze Figure 2 for dynamite cartridges contains behind the plug fa
fulminating mercury cap 9; the space between the latter and the priming b, is filled
up with a small tuft h of sheeps wool or the like in order to keep the cap securely in
position.
Either perforated wooden plugs i are inserted at several points in the tube a as in
Figure 1, in order to constitute a guide for the friction wire, or the entire tube a is
filled up with a guide socket ; Figure 2.

page_text: Figures 3 and 4 show that the fuze z for powder, and ¹ for dynamite is inserted in
the charge of the wall of the bore hole, after the blasting charge of powder P or of
dynamite D has been introduced to the bottom of the said bore hole. The end of the
dynamite fuze z¹ being previously fitted with the small firing cartridge D¹ of dynamite.
The charge is now moderately compressed, and the bore hole is tamped with clay.
The rear end of the fuze z or z¹ protruding too far can be cut off.
The firing cord represented in Figure 5 is now applied in the following manner
viz. one of the loops or hooks k which are arranged at both ends of the primary cord s
is hooked to one of the friction wire loops of a pair of bore holes 1 and 2, 3 and 4,
5 and 6 and so on. Of every two adjoining primary cords s hooked in this manner,
one is then drawn through one of the rings which are arranged at the ends of the
secondary cords whereupon also the second loops or hooks k₁ of the cord s drawn
through is hooked to the corresponding friction wire loop, and after the ring r of
another cord & has eventually been drawn over the cord s', the same mode of operation
is performed as regards the cords of the second pair of bore holes and the second
ring of the cord s.
In this manner both ends of the cord to which finally the firing cord S of about
20 metres in length is hooked act each upon a cord, either end of which acts again
upon a cord and so forth until the last or primary cords act each upon two friction
wires. By reason of the capability of displacement of all the connections. All the
cords of the system can be stretched simultaneously by pulling the firing cord S at
different angles. This is done first by a moderately strong and gradual pull, where-
upon by a short powerful jerk all the friction wires c are pulled through the
priming cap.
If, instead of four fuzes only three fuzes are to be connected by the three cords 8, 8¹, s³
in one group, both loops or hooks k and k¹ of one of the cords s are of course hooked
in one friction wire loop.
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-
First. The improved means of firing the blasting charges used in mining and similar
operations, which consists in operating the friction fuzes inserted in the charge, by
means of firing cords, thereby avoiding the use of a firing flame or of an incandescent
body as above specified.
Second. The firing of a number of blasting charges simultaneously by means of
fuzes similar to friction priming tubes, with a firing cord.
Third. The friction fuzes as above described for the firing of dynamite, consisting
of a fuze similar to a friction priming tube, which however, instead of a bouncing
charge, contains a fulminating mercury cap and is provided with a small dynamite
firing cartridge.
Fourth. For the purpose of simultaneously firing several blasting charges by means
of the above described friction fuzes the connection in pairs of the wire eyes or loops
by primary cords and the further connection of every two of the said cords by a
secondary cord, the end rings of which can be displaced upon the former, the secondary
cords are again displacibly connected with a similar cord which is finally connected to
the firing cord proper so as to be displaceable thereon as above described.