IMPROVEMENTS IN PERCUSSION CAPS AND DETONATORS
Year: 1879

page_text: LETTERS PATENT to Frank Wirth, of the Firm of Wirth and Company,
A
Patent Solicitors, at Frankfort-on-the-Main, in the Empire of Germany, for
the Invention of "IMPROVEMENTS IN PERCUSSION CAPS AND DETONATORS.”
communication from Gustav Bloem, trading under the Firm of Braun & Bloem,
of Düsseldorf, in the Empire of Germany.
Sealed the 1st August 1879, and dated the 6th February 1879.
PROVISIONAL SPECIFICATION left by the said Frank Wirth at the Office
of the Commissioners of Patents on the 6th February 1879.
FRANK WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at Frank-
fort on the Main, in the Empire of Germany. "IMPROVEMENTS IN PERCUSSION
CAPS AND DETONATORS." [A communication from Gustav Bloem, trading under
the Firm of Braun & Bloem, of Düsseldorf, in the Empire of Germany.]
The said improvements consist,-
First. In weakening the bottom of the cap by a ring or cross.
Secondly. In closing the cap as firmly as possible at the top, which is effected
by placing a conical copper cap within the same, provided with a hole in its
bottom.
Thirdly. In strengthening the sides of the cap as much as possible.
Detonating caps, as is well known, serve to explode dynamite and similar sub-
stances by a strong shock and great heat.
By concentrating these as much as possible towards the centre of the exploding
cartridge or blasting hole charge, the latter are rendered the more reliable.
The aforesaid conical copper cap can also be held within the outer cap by
narrowing the mouth of the latter.
The manner of applying the above named principles of construction may be
varied as desired according to circumstances.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frank Wirth in the Great Seal Patent Office on the 6th August.
1879.
FRANK WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at Frank-
fort-on-the-Main, in the Empire of Germany. " IMPROVEMENTS IN PERCUSSION

page_text: CAPS AND DETONATORS." A communication from Gustav Bloem, trading under the
Firm of Braun and Bloem, of Düsseldorf, in the Empire of Germany.
The said improvements consist, first, in weakening the bottom of the cap by ring
or cross.
Secondly.-In-closing the cap.as firmly as possible at the top, which is effected
by placing a conical copper cap within the same, provided with a hole in its
=bottom=
Thirdly. In strengthening the sides of the cap as much as possible.
Detonating caps, as is well known, serve to explode dynamite and similar sub-
stances by a strong shock and great heat.
By concentrating these as much as possible towards the centre of the exploding
cartridge or blasting hole charge, the latter is rendered the more reliable.
The aforesaid conical copper cap can also be held within the outer cap by
narrowing the mouth of the latter.
In the accompany Drawing,-
Figure 1 represents in section an ordinary detonating cap provided with an
explosive filling A and a fusee B.
Figure 2 is a sectional view of an ordinary cap without a fusee.
Figure 3 shews in section my improved cap complete; and
Figure 4 is a similar view of the said cap without the fusec.
Figure 5 shews one of my improved caps, whose bottom is weakened by a ring-
shaped groove being pressed in the same, and also shewing the sides strengthened;
and
Figure 5ª is a bottom view of the same;
Figure 6 shews an improved cap with a weakened bottom and ordinary sides;
and
Figure. Ga is a bottom view of the same.
Figure 7 shews an improved cap with the bottom weakened by a + shaped
and
groove being pressed in the same, and with ordinary sides;
Figure 7a is a bottom view of the same.
Figure 8 shews an improved cap with its bottom weakened by a cross being
impressed in the same, and with the sides strengthened; and
Figure 80 is a bottom view of the same.
Figure 9 represents the inside cap, which is inserted in my improved caps;
and
Figure 9a is a plan of the same.
Figure 10 is a sectional view through one of my improved caps, the bottom being
weakened by impressing the same with a ring-shaped groove, and the sides
strengthened by being thickened and the top contracted.
Having thus fully described the said Invention, and the manner of performing
the same, I wish it understood that I claim, the improvements in percussion caps
and detonators, substantially as set forth.
☐ In; witness whereof, I, the said Frank Wirth, have hereunto set my hand
and seal, this Twenty ninth day of July, in the year of our Lord One
thousand eight hundred and seventy-nine.