Improvements in the Means for Blasting by Explosives.
Year: 1892

page_text: Date of Application, 23rd June, 1892
Complete Specification Left, 23rd July, 1892-Accepted, 27th Aug., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Means for Blasting by Explosives.
I, FRIEDRICH PFEIFFER of Goslar am Harz in the German Empire, Public
Official, do hereby declare the nature of this invention to be as follows:-
This invention relates to a process or means for exploding charges of explosive
material in bore holes. The object of the invention is to insure the explosion of
the whole of the charge, that is to say, without any residual unexploded portion of
the explosive to simplify the operation of tamping and to enable such operation
to be performed without danger.
It. has hitherto been customary in blasting by means of bore holes charged with
an explosive to effect the ignition of the explosive direct, underneath the tamping.
According to this invention the explosive having been placed at the bottom of
the bore hole, water contained in a vessel open at top and fitting the bore hole is
placed in the same to serve as the tamping. The bore hole and water vessel is
then closed at top by a priming cartridge which may be exploded by electric spark,
fuze, or other suitable means. The gases evolved upon the explosion of the
cartridge force the water with such force against the explosive charge as to cause
complete explosion of the same.
The priming cartridge is formed of a casing having a small orifice at top for the
percussion cap or its equivalent. An explosive charge is placed in the upper
separated part of the casing underneath the orifice and the lower open end of the
same fits on to the water vessel in the borehole.
In cases where it is desired to prevent the issue of any flame from the cartridge
when this is exploded as for instance in mines where inflammable air or dust is
present, the cartridge is constructed with an additional compartment at top for
containing water or other flame preventive the means for effecting explosion passing
through the same to the explosive charge of the cartridge.
Dated this 23rd day of June 1892.
T. R. SHILLITO,
89, Chancery Lane, London, W.C., Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Means for Blasting by Explosives.
I, FRIEDRICH PFEIFFER of Goslar am Harz in the German Empire, Public
Official, 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 relates to a process or means for exploding charges of explosive
material in bore holes. The object of the invention is to insure the explosion of
the whole of the charge, that is to say, without any residual unexploded portion of
the explosive.;. to simplify the operation of tamping; and to enable such operation
and also the explosion to be effected without danger.
It has hitherto been customary in blasting by means of bore holes charged with
an explosive, to effect the ignition of the explosive direct, underneath the tamping.
According to this invention the explosive having been placed at the bottom of
the bore hole, water is poured into the same and above the water an exploding
cartridge, or preferably, water contained in a vessel open at top into which an
exploding cartridge is fitted the whole fitting the bore hole into which it is placed.
The cartridge may be exploded by electric spark, fuze or other suitable known

page_text: means. The gases evolved upon the explosion of the cartridge force the water
with such force against the explosive charge at the bottom of the bore hole as to
cause complete explosion of the same.
In the accompanying drawing
Fig. 1. shews a slanting bore hole charged in accordance with this invention,
Fig. 2 a water vessel,
Figs. 3 and 4 constructions of exploding cartridges.
a is the explosive blasting charge, & the water taiping, e the exploding cartridge,
d a water vessel.
The cartridge (Fig. 3) is formed of a casing e having at one end a small orifice f
for the reception of a firing cap or its equivalent. This end of the cartridge is
charged with an explosive e¹ the other end separated therefrom serving to take on
to the end of the water vessel d when this is used as is preferred. The water
vessel may be constructed of any suitable material of sufficient strength.
The cartridge shewn in Fig. 4 is for use where it is desired to prevent the issue
of any flame into the surrounding air when the explosion is effected, as for instance
in mines where inflammable air or dust is present. e is the casing, e' the explosive,
the firing cap of the cartridge in this case fitting hermetically or nearly so into
orifice and extension of the same, the other end of the firing cap extending to
the explosive past an outer compartment g filled with a flame preventing substance
or liquid, water for instance and the inner end of the cartridge may be formed to
take on to the end of water vessel d.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :
1. The process of exploding the explosive charge of bore holes in the manner
that the explosion of the charge placed underneath water tamping is effected from
above the said water tamping by the action of gases evolved. from an explosive
substantially as described and shewn.
2. In the process referred to the application of a water vessel closed at one end
and serving to contain the water tamping, substantially as described and shewn...
3. In the process referred to the application of an exploding cartridge consisting
of a casing e provided at one end with an orifice for the reception of a firing cap
and at this end charged with an explosive whilst the other end is formed to fit on
the end of water vessel d, substantially as described with reference to Fig. 3 of the
drawing.
4. In the process referred to the application of an exploding cartridge consisting
of a casing e provided at one end with an orifice and extension of same which
closes tightly round a firing cap; the outer compartment of the casing serving for
the reception of a flame destroying substance or liquid, the central portion of the
casing for the explosive and the inner end thereof to fit on the open end of water
vessel d, substantially as described and shewn with reference to Fig. 4 of the
drawing.
Dated this 23rd day of July 1899
T. R. SHILLITO,
89, Chancery Lane, London, W.C., Agent for the Applicant.