IMPROVEMENTS IN CENTRAL-FIRE CARTRIDGES
Year: 1881

page_text: LETTERS PATENT to Frank Wirth, of the Firm of Wirth and Company, Patent
Solicitors, at Frankfort-on-the-Main, in the Empire of Germany, for an
Invention of "IMPROVEMENTS IN CENTRAL-FIRE CARTRIDGES."
A com-
` munication from Gustav Bloem, trading under the Firm of Braun & Bloem,
PROVISIONAL SPECIFICATION 'left by the said Frank Wirth at the Office
of the Commissioners of Patents on the 1st January 1881.
:
FRANK WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at Frankfort
on the Main, in the Empire of Germany. "IMPROVEMENTS IN CENTRAL-FIRE
CARTRIDGES." A communication from Gustav Bloem, trading under the Firm of
Braun & Bloem, of Düsseldorf, in the Empire of Germany.
This Invention relates more particularly to anvils for central fire cartridges, and
has for its object to ensure a correct position of the anvil with regard to the
percussion cap, to offer a solid and safe resistance to the impact of the hammer, and
to facilitate the manufacture of good cartridges.
The anvil consists of a short metal pin provided in the centre with a shoulder,
serving as an abutment against the base of the anvil cap, through which the pin or
nipple partly passes, and holding the latter exactly in the centre of the cup.
The anvil cup is perforated in the centre for the reception of the pin or nipple,
which fits with a slight clearance in order to allow the passage of the igniting
spark.
The upper face of the anvil is either slightly hollowed out, or it is provided
with a rounded point or with radial ribs or projections for the purpose of increasing
the sensitiveness of the inflammation. The face of the shoulder which comes in
contact with the base of the anvil cup is either quite plain, or it is provided with
recesses or hollowed, or provided with projections to facilitate the passage of the
igniting spark.
Where anvils with solid shoulders are used two or more openings may be
applied in the base of the anvil cup to provide a passage for the spark from the
percussion cap. The anvil extends sufficiently below the base of the anvil cup that
the spent percussion cap can be ejected after the cartridge has-been exploded.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frank Wirth in the Great Seal Patent Office on the 28th June
1881,
Frank WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at Frankfort
on the Main, in the Empire of Germany. "IMPROVEMENTS IN CENTRAL-FIRE
CARTRIDGES." A communication from Gustav Bloem, trading under the Firm of
Braun and Bloem, of Düsseldorf, in the Empire of Germany.
This Invention relates more particularly to anvils for central fire cartridges, and
has for its object to ensure a correct position of the anvil with regard to the
percussion-cap, to offer a solid and safe resistance to the impact of the hammer,
and to facilitate the manufacture of good cartridges, and consists in the following
improvements :-
The accompanying Drawing will serve to illustrate the Invention. The anvil,
Figs. 1, 2, and 3, consists of a short metal pin provided in the centre with a
shoulder, serving as an abutment against the base of the anvil cup, through which
the pin or nipple partly passes, and holding the latter exactly in the centre of the
cup. The anvil cup is perforated in the centre for the reception of the pin or
nipple, which fits with a slight clearance in order to allow the passage of the igniting
spark.
The upper face of the anvil is either slightly hollowed out, as in Fig. 1a, or it is.
provided with a rounded point, as in Fig. 1b, or with radial ribs or projections, as
in Fig. 10, for the purpose of increasing the sensitiveness of the inflammation. The
face of the shoulder, which comes in contact with the base of the anvil cup, is
either quite plane, as in Figs. 1ª, 1b, 1° (solid shoulder), or it is provided with
recesses or hollowed, as in Fig, 2, or provided with projections, as in Fig. 3, to
facilitate the passage of the igniting sparks, as indicated by arrows in Figs. 5 and 6.
Where anvils with solid shoulders are used two or more openings may be applied
in the base of the anvil cup to provide a passage for the spark from the percussion
cap, as shown in Fig. 4. The anvil extends sufficiently below the base of the anvil
cup that the spent percussion cap can be ejected after the cartridge has been
exploded. The following advantages arise from this Invention:-The anvil with
its shoulder is always placed accurately in the centre of the anvil cup, and therefore
of the percussion cap, and offers a solid and safe resistance to the impact of the
hammer, which is not the case with the nipples or anvils at present in general use.
The ignition of the cartridges is thereby assured, and the many failures avoided.
For metallic cartridges, in which hitherto the percussion cap has been pressed on
to the anvil cup, this Invention provides likewise a considerable improvement in
the manufacture as well as in the reliability of ignition (see Fig. 6). The manu-
facture of fixed percussion-caps is difficult; it requires many steel dies, which
moreover are frequently bursting, and thereby interrupting the manufacture.
Many otherwise faultless metallic cartridges cannot be used, solely in consequence
of the use of faulty percussion-caps, but most frequently after they have been once
used. All these difficulties and losses are obviated by means of the new nipple
with shoulder. The anvil cup without the percussion cap can be manufactured
very easily and in the exact dimensions required.
The nipples can be pressed with facility and in the exact length without. waste
of material.
The nipples can easily be replaced by new ones in case they have been deformed
by use, and the expensive metallic shell of the cartridge may be used again,

page_text: Moreover the bottom of the metallic cartridge requires no great thickness if only
the anvil cup without percussion cap is stamped therein.
The metallic cartridge may be made of much lighter material, and therefore
cheaper.
In witness whereof, I, the said Frank Wirth, have hereunto set my hand and
seal, this Eighteenth day of June, A.D. 1881.