An Improvement in Electrical Glow Lamps.
Year: 1895

page_text: Date of Application, 24th Jan.. 1895
Complete Specification Left, 3rd Oct., 1895-Accepted, 9th Nov., 1895
[Communicated from abroad by Messrs. SIEMENS & HALSKE, of Berlin, in the
German Empire, Electrical Engineers.]
An Improvement in Electrical Glow Lamps.
We, SIEMENS BROTHERS & Co., LIMITED of 12 Queen Anne's Gate,
Westminster, in the County of Middlesex, Electrical Engineers, do hereby
declare the nature of this invention to be as follows:-
In order to save some of the platinum employed for the leading-in wires of an
electrical glow lamp, wires of less expensive metal have been soldered to the short
pieces of platinum wire which are sealed into the glass, but this construction is
objectionable owing to the want of sufficient stability of the wires when their
junctions are close to the glass. The present invention has for its object to ensure
stability of the wires thus connected. For this purpose, each leading-in wire is
made up of two pieces of comparatively inexpensive wire, such as copper or nickel,
soldered or welded to the ends of a short piece of unoxidisable wire such as
platinum, and this platinum is sealed into the glass in such a manner that its
junctions with the other wires are quite imbedded in the glass.
Dated this 24th day of January 1895.
ABEL & IMRAY,
Agents for the Applicants.
An improvement in Electrical Glow Lamps.
We, SIEMENS BROTHERS & Co. LIMITED, of 12, Queen Anne's Gate,
Westminster, in the County of Middlesex, Electrical 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:
In order to save some of the platinum employed for the leading-in wires of an
electrical glow lamp, wires of less expensive metal, such as nickel or copper, have
been soldered to the short pieces of platinum wire which are sealed into the glass.
It has been found however that this construction suffers from the defect that the
leading-in wires do not possess sufficient stability if the soldered junction is close to
the glass, while on the other hand the object of such a construction, namely the
saving of platinum as much as possible, requires that the shortest possible length of
platinum shall be used.
The present invention has for its object to insure stability of wires thus
connected; for this purpose the leading-in wires are constructed of a very short
piece of suitable non-oxidisable metal such as platinum and two pieces of any
suitable less expensive metal such as copper or nickel welded or soldered together,
such wires being then sealed in the glass in such a manner that both the points of
union of the platinum with the other wires are completely imbedded therein.

page_text: By this means, sufficient stability for the leading-in wires is insured while a
material reduction of the cost of construction is attained.
The accompanying drawing shews a glow-lamp constructed according to the
above described invention. p are the pieces of platinum wire which serve to
hermetically seal the leading-in wires into the glass, Ca are copper wires that
establish the connection with the external leads and Care copper wires that
establish the connection with the incandescence filament R, which is secured to
these wires in the usual manner.
17.7
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed; we declare that what we'
claim is :-
1811
In electrical glow lamps, constructing the leading-in wires of a short length of
non-oxidisable metal wire such as platinum to each end of which is welded or
soldered a length of wire of a less expensive metal, such as copper or nickel, the
platinum wire being sealed in the glass in such manner that both points of union
are completely imbedded in the glass, substantially as described.
Dated this 3rd day of October 1895.
ABEL & IMRAY,
Agents for the Applicants.