ImprovemenTS IN ELECTRIC LAMPS
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by the said Edgar Paul Ward at the
Office of the Commissioners of Patents on the 5th July 1881.
_EDGAR PAUL WARD, of 1, Lillyville Road, Fulham, in the County of Middlesex.
“ImprovemenTS IN ELECTRIC LAMPS."
My Invention relating to improvements in electric lamps has reference to the
conveyance of the electric current into the lamp.
Heretofore in lamps of the type known as the Swan lamp it has been customary
to employ platinum wire, connected at one end to the glass bulb by the fusion of
the glass on to it, and connected at the other end to the carbons either directly or
through the intervention of intermediate conductors.
According to my Invention I substitute for the platinum wires iron or steel
wires, which are by preference connected directly to the carbons in the manner
hereinafter described, and are connected to the glass bulb in the following
manner-Each wire is first enclosed in an envelope of glass, and the two envelopes
are connected together by fusion at a suitable distance from one end. The
combined envelope thus produced containing the wires is then united by fusion to
the glass bulb for the latter to be exhausted, the glass envelopes forming a
protection against any chemical action to which they might be subjected during
manufacture.
In lieu of employing glass a protective envelope for the wires of plaster, metal,
or any other suitable material may be employed, the object being to protect the
the iron or steel against chemical action during the manufacture of the lamp.
The inner ends of the wires are connected to the carbons, by means of single
spirals formed on the wires, and so arranged as to grip the ends of the carbons
by their own elastic action without the intervention of any auxiliary binding
material.
By the use of my Invention considerable economy is effected both in the cost of
material and labour over the arrangements heretofore employed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edgar Paul Ward in the Great Seal Patent Office on the 2nd
January 1882.
EDGAR PAUL WARD, of 1, Lillyville Road, Fulham, in the County of Middlesex.
"IMPROVEMENTS IN ELECTRIC LAMPS."
My said Invention relating to improvements in electric lamps has reference to
the conductors for the conveyance of the electric current into the lamp.
Heretofore in incandescent lamps of the type known as the Swan lamp it has
been customary to employ platinum wire, connected at one end to the glass bulb
by the fusion of the glass on to it, and connected at the other end to the carbons
either directly or through the intervention of intermediate conductors.
According to my said Invention I am enabled to substitute for the platinum
wires iron or steel wires, which are by preference connected directly to the carbons,
and are connected to the glass bulb in the following manner :-Each wire is first
coated or enclosed in an envelope of glass to the required extent, and the two
envelopes thus formed are then connected together by fusion at a suitable distance
from one end. The envelopes containing the wires are then united to the glass
stem of the bulb by fusion ready for the bulb to be exhausted, the glass envelopes
by extending outside the lamp to a considerable distance beyond the point of
attachment to the stem of the bulb forming a protection against oxidation or any
other chemical action to which the wires might be subjected during fusion or other
parts of the manufacture.
After the glass envelope has been attached to the bulb the portion of the
envelope projecting outside the lamp may be broken away if desired.
If found desirable as an extra safe guard against leakage, I may afterwards
apply to the point of junction of the wires with the stem of the bulb any suitable
'cement, such, for example, as borax, silicate of potash, and the like.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the hereinbefore in part
recited Letters Patent is,-
The use of a glass coating or envelope for protecting iron or steel wire con-
ductors in incandescent lamps against chemical action during their manufacture,
substantially as herein before described.
In witness whereof, I, the said Edgar Paul Ward, have to this my Speci-
fication set my hand and seal, this Second day of January, One thousand
eight hundred and eighty two.
EDGAR PAUL WARD. (L.S.)