Method of and Means for Renewing or Repairing the Filaments of Incandescent Electric Lamps.
Year: 1891

page_text: Date of Application, 7th Apr., 1891
Complete Specification Left, 5th Jan., 1892—Accepted, 27th Feb., 1892
PROVISIONAL SPECIFICATION.
Method of and Means for Renewing or Repairing the Filaments of
Incandescent Electric Lamps.
I, HARRY CHAPMAN, of Green Mount, Morley, near Leeds, Electrician, do
hereby declare the nature of this invention to be as follows:-
The object of my invention is to renew or repair the filaments of incandescent
electric lamps.
Hitherto on the disintegration of the filaments the lamps have been discarded or
regarded as useless, but by my invention the lamps are rendered as good as new,
and can consequently be used again.
In carrying out my said object I open the end of the bulb by removing (by filing
or otherwise) the end of the nipple, or I may form an opening at any other suitable
part of the bulb. I then withdraw the filament, clean the inside of the bulb by
heating it to nearly or about a red heat, then cut off the bad or unnecessary part of
the filament and replace the filament in the bulb again and join it to the conducting
wires. I then exhaust the air by means of the mercurial air pump or other such
means, and seal the opening or end of the bulb by a gas jet or the like heating
means.
Or in lieu of withdrawing the filament from the bulb, I may join a piece of
carbon on at the broken place and so effect the continuity of the filament.
For the purpose of making the joint of the filament and the wires I may use a
composition or carbon paste, which is applied in a soft state, and afterwards
hardened or carbonized by the application of heat.
Dated this 3rd day of April 1891
JOHN E. WALSH,
Royal Exchange Chambers, Boar Lane, Leeds,
Agent for the Applicant.

page_text: Fig. 5. shews an appliance for baking or carbonizing the joint between the
conducting wires and filament.
In carrying out my object I open the end of the bulb A forming by preference in
the end of the nipple B at C a slight opening of such size as will prevent too great
a current of air entering and shattering the filament, the opening being after-
wards widened by heating the nipple and opening such out by means of a wire.
In case a new filament is required withdraw the old filainent D and clean the
inside of the bulb A by heating it, say in an oven to about a red heat, and when
cool, place a new filament in the bulb A. and join it to the conducting wires E as
hereinafter set forth.
For the purpose of making the joint of the filament D with the wires E I use a
composition or carbon paste in a soft state which is applied to the end of wires and
filament, through the hole C, by means of an instrument as shewn at Fig. 3, the
paste being afterwards hardened and carbonized by connecting a suitable instrument
insulated along the stem S and such as shewn in Fig. 5. to one pole of a battery or
dynamo and the conducting wires in lamp to the other pole of battery or dynamo,
the instrument being then brought in contact with the pasted joint, it is carbonized
by a current of electricity arcing" across, thus perfecting the joint.
The carbon paste may consist of tar, powdered carbon, and turpentine or in lieu
thereof other carbon compositions well known to electricians may be utilised.
In lieu of withdrawing the filament D from the bulb A I may apply the paste to
the broken place and so effect the continuity of the filament D by carbonizing the
paste so applied.
Or I may break off the unbroken leg of the filament D by the means of an instru-
ment such as shewn at Fig. 4 and make both legs of the filament D the same length
by bringing them outside the opening C by means of the said instrument, then
nipping off the portion of the filament D to the required extent, then turning the
filament round and joining in the manner as hereinbefore described.
I exhaust the air from the bulb A by means of a mercurial air pump or other
known means and seal the opening C or end of the bulb A by a gas jet or the like.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
(1.) The method of renewing the filament of an incandescent electric lamp which
consists of introducing the filament through a hole in the lamp and cementing or
joining such filament to the conducting wires by means of carbon paste afterwards
hardened and carbonized by the application of an electric current made to "are
between the joint and the end of the insulated wire inserted through a hole in the
globe, all substantially in the manner as described.
**
(2) The method of repairing the filament of an incandescent electric lamp which
consists in cementing or reuniting such filament at the breakage by applying a
carbon paste through a hole in the lamp to the breakage and carbonizing same by
a current of electricity made to "are" between the carbon joint and insulated wire
applied through a hole in the lamp all substantially in the manner as described.
(3.) The method of repairing the filament of an incandescent electric lamp which
consists in making the legs of the filament the same length and cementing such
filament direct on to the conducting wires by the application of carbon paste to the
joints which joints are afterwards carbonized by a current of electricity made to
arc "between the carbon joints and insulated wire applied through the hole in the
lamp, substantially in the manner described.
Dated this 4th day of January 1809
JOHN E. WALSH,
Royal Exchange Chambers, Boar Lane, Leeds,
Agent for the Applicant.