Improvements in Igniting-devices for Cartridges.
Year: 1894

page_text: Date of Application. 7th Mar., 1894-Accepted, 7th Apr., 1894
COMPLETE SPECIFICATION.
[Communicated from abroad by the Firm of FRIED. KRUPP GRUSONWERK,
Magdeburg-Buckau, in the Empire of Germany, Manufacturers.]
Improvements in Igniting-devices for Cartridges.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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 improvements in igniting devices for cartridges.
The object of the said invention is to combine with a cartridge the supple-
mentary charge, necessary for igniting smokeless powder and consisting of loose
gunpowder, and to insert it into the cartridge case, in such a manner, that the
formation of a tight joint between the case and the device containing the said charge
is insured.
According to this invention I construct a device which contains in two different
cavities, separated from each other by an anvil provided with ignition channels,
the percussion cap with the explosive charge, and the aforesaid supplementary
charge necessary for igniting smokeless powder, but which differs from the
igniting appliances heretofore used for the same purpose by the manner in which
the device is applied to the base of the cartridge case and which ensures the
formation of a perfectly gas-tight joint between them..
In order that the said invention may be clearly understood I will now proceed
to describe the same with reference to the accompanying drawings, in which:
Figure 1 is a central longitudinal section, of a cartridge fitted with an improved
igniting-device according to my invention.
Figure is a view similar to Figure 1 shewing an alternative arrangement of
the said igniting-device.
Like letters of reference indicate corresponding parts in both the drawings.
The improved igniting-device consists of a metallic plug provided with a
perfectly smooth, cylindrical or slightly conical outer surface, which plug in
Figure 1 is formed of an outer hollow cylinder or cone a and a smaller co-axial
hollow cylinder connected with the former by the bottom c and carrying the
anvil d with ignition channels therein. The cavity of the inner cylinder b
serving for the reception of the percussion cap e is separated from the cavity of
the outer cylinder or cone a containing the supplementary charge g, by the
anvil d. As the supplementary charge consists generally of loose gunpowder,
it is expedient to prevent its falling from the cavity of the cone or cylinder a
by a layer of shellac h. In the arrangement shown in Figure 2 the thickness
of the bottom c is made equal to the height of the inner cylinder b of Figure 1,
so that the annular space which would otherwise exist within the cylinder a is
avoided.
The plug is pressed axially into a hole of suitable shape in the base of the
cartridge case which is reinforced by a boss f. In order that the outer periphery
of the plug and the inner periphery of the boss may exert considerable pressure
against each other, to ensure a perfectly tight joint, it is necessary to make the
outside diameter of the plug slightly greater than the inside diameter of the
hole which receives it. When the slightly conical or cylindrical plug, the metal
of which is slightly thinned at the front end, is forced axially into its bearing
in the boss fit acts as a round wedge and with considerable force somewhat

page_text: expands the said boss, the latter at the same time slightly compressing the plug..
By the pressure thus produced perpendicularly to the surfaces of contact, a
hermetically tight joint is formed. This is necessary to ensure that in the
explosion of the supplementary charge, the powder gases generated will press
the outer periphery of the plug against its bearing, inasmuch as with the slightest
leakage at the joint the gases would enter and loosen the plug by pressing the
wall from its contact with the aforesaid hole.
Igniting devices constructed according to this invention have the advantage
that they can be cheaply made and easily removed from the cartridge for
re-filling purposes.
Having now particularly described and ascertained, the nature of the said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondents, I declare that what I claim is :-
1. An igniting device for, cartridges in which the percussion cap and the
supplementary charge are contained in a cylindrical or slightly conical plug and
are separated by an anvil, for the purpose specified.
2. The combination of an igniting-device or plug such as that hereinbefore
described, with a cartridge the base of which is specially constructed to receive
and retain the said plug, substantially as hereinbefore described, and for the
purpose specified.
3. An igniting-device substantially as herein before described with reference to
Figure 1 or to Figure 2 of the accompanying drawings, for the purposes specified.
Dated this 7th day of March 1894.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.