Improvements relating to the Manufacture of Illuminating Con- ductors for Electric Lamps, and to Solutions and Apparatus for use in such Manufacture.
Year: 1889

page_text: Date of Application, 13th July, 1889
Complete Specification Left, 9th Oct., 1889-Accepted, 7th Dec., 1839
PROVISIONAL SPECIFICATION.
[Communicated from abroad by SILVANUS FREDERICK VAN CHOATE, of the City and
State of New York, but now residing in Boston, Massachusetts, United States of
America, Electrical Engineer.]
Improvements relating to the Manufacture of Illuminating Con-
ductors for Electric Lamps, and to Solutions and Apparatus for
use in such Manufacture.
1, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, in the County of Middlesex, do hereby declare the nature of
this invention to be as follows:-
This invention relates to the manufacture of improved filaments or illuminating
conductors for electric lamps and to solutions and apparatus for use in such
manufacture.
The main object of my said invention is to produce filaments that will have a
greater efficiency as well as give a more agreeable light, than filament as heretofore
made, while their manufacture and use will be attended with a higher mathematical
precision.
To this end my said invention comprises various improvements hereinafter
mentioned.
In carrying out my invention different metallic substances and materials may be
employed, and the nature of the apparatus and processes may be varied, but I prefer
the following
-:
I employ as the base or foundation of my filament or illuminating conductor
any suitable fibre or material of suitable form, size and properties for the purposes
desired.
This fibre or material is subjected to a treatment in an iodine solution, or any
iodate or iodic compound or any ioduret or iodyretic compound or combined with
aluminium or any sulphate of aluminium or of aluminium and potassium or of
potassium, or any oxide of potassium or either or any of the above combined with
any alkaline metallic compound, or 1 may use vanadium or compounds of it and
other metals and substances; or other substances or metals combined with vanadie or
iodic or aluminium compounds.
In preparing and using the above substances or reagents or any of them, alcohol of
a high degree of proof or of such quality and strength as may be convenient, may be
employed and either with or without the application of heat or evaporation, as may
be required to produce the results sought.
In the preparation of the iodine solution the aluminium or vanadium may be
granulated or pulverized or it may be in very thin sheets or small particles dissolved
in iodine or alcohol, or in a combination of them, and if desired, inay be submitted
to evaporation to increase the strength or mix and assimilate the same to any required
extent.
After the solution has been brought into the required condition the filament or the
material or base of the filament is subjected to treatment by the solution by passing it
through or by submerging it in the same, or otherwise.
If the filament or illuminating conductor is in the shape of a thread or attenuated
fibre it should be passed through a bath of the solution and dried or baked a number
of times sufficient to produce the effects desired, in some instances being pussed through
the solution as many as twenty to thirty times.
The filament has now become thoroughly impregnated and combined with the sub-
tance of the solution.
The filament or base is now subjected to a baking or roasting process with

page_text: plumbago in a closed retort or crucible being submitted to an intense heat in a
furnace having a temperature of from 1000° to 2000° Fahrenheit. It is then allowed
to cool down.
The filaments are now made into the desired lengths and treated by a process
of electro-metallurgy, the filament during this last process being enclosed in a her-
metically sealed glass flask or bottle containing a supply of the iodine and aluminium
solution above described the air being exhausted therefrom by means of an air force-
pump or otherwise; while the filament is thus enclosedțin the flask and subjected to
the vapors of the solution a current of electricity is passed through it causing a
deposition of a metallic nature from the solution to be combined with the substance of
the base, and also causing a homogeneous metallic surface to be formed upon its
exterior by the iodide of aluminium or other metallic substances in the solution.
The desired amount and perfection of this metallic or semi-metallic coating upon
the filament is mathematically determined while under treatment by an electrical
apparatus designed for the purpose; and when filaments have been passed through
these processes they attain or possess the quality of a metallic or semi-metallic sub-
stance or conductor of electricity, and are ready for use by insertion in hermetically
scaled cases, in vacuo or otherwise as may be desired.
Dated this 13th day of July 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to the Manufacture of Illuminating Con-
ductors for Electric Lamps, and to Solutions and Apparatus for
use in such Manufacture.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, in the County of Middlesex, do hereby declare the nature
of this invention and in what manner the same is to bo performed, to be particularly
described and ascertained in and by the following statement :-
This invention relates to improved filaments or burners for electric lighting (lamps)
and the modes or methods used in the manufacture or production of such filaments or
burners; and the objects of my invention are to produce filaments that will give a
greater efficiency in light for a given expenditure of electrical energy, as wellas a more
desirable light while their manufacture and use will be attended with a higher mathe-
matical precision than las heretofore been attained.
To these ends my invention consists in a novel employment and combination of
materials, and forming a compound of vegetable and metallic substances; the latter
substances being brought to a fluid state by dissolvents and then consolidated into a
semi-metallic compound, the combination being aided by heat, electro-metallurgy,
electro-chemistry and thermo-electricity, all substantially as hereinafter described and
set forth.
In my provisional specification of October 31st 1878, No. 4388, I mention the use
and employment of "asbestos, mica, platinum, or carbon, or any combination of them,
and such other materials as may be required to give the proper affinity and homo-
geneousness to the material. These materials are mixed and prepared to form a
metallic or semi-metallic material which becomes incandescent under the influence of
electricity and gives or forms the illumination." And it is further stated in said
specification, that "this metallic or semi-metallic substance or material is, preferably,
made into wire or ribbon of proper size and formed into arcs, spirals or spiral globe-
siaped illuminators or burnors, or the material may be formed into discs, or globes,
or spirals wound around a central wire or body or into other shapes required to form
the light."
In my present invention and improvements it will be observed that I do not use
ether, ethylate, mothylate or wood spirit in any form; nor acid or acetate; nor
sulphates or sulphur in any form; nor oxide or oxides; nor salt or any form of soda;

page_text: nor chlorides or chlorine in any shape; nor any oxydizing substance. These substances
would be deleterious to my filament. The chemicals I use in preparing my filament
are used as dissolvents only.
Neither do I use the electric current as a drying agent, but I use it for electro-
plating purposes.
In carrying out my invention other metallic compounds, substances and materials
may be employed, and various machines and apparatus and processes may
be used besides those herein specifically named that is to say; I may use any
solution of either iodine, alcohol, ammonia, potassium, or any alkalino or alcoholic
substance acting as a dissolvent in combination with any substance or material; or
combinedly forming any iodine solution, or any ioduret or iodic compound, or com-
bined with either aluminium or vanadium in any shape, in forming compounds and
solutions for dipping, impregnating or electro-plating filaments or the base or bases
for filaments or burners for electric lighting; but more specifically speaking, I prefer
the materials and processes hereinafter named.
In describing my invention and the mode, materials and apparatus employed in
carrying it out, I find it convenient to arrange it numerically into nine different
parts or steps; viz. :-
Step 1st is the base, foundation or material;
Step 2nd is the preparation of the material or base ;
Step 3rd is the solution and its component parts;
Step 4th is the treatment of the filament or base by the solution or otherwise ;
Step 5th is the fusing process;
Step 6th is the first or preliminary plating process;
Step 7th is the jointing, connecting and electro-metallic cementing process;
Step 8th is the electro-metallurgy and final plating process, and
Step 9th is the finishing and measurement of the filament or burner;
Step (1). Referring to the above, the base or foundation of my filament or burner
may bo composed of any suitable fibre or material and may be of any required
form or size for the purpose desired; any attenuated fibre or thread will answer;
but the most convenient and practical is a fibre or thread made of the best Soa
Island or Egyptian cotton.
(2). The material or base of the filament is first soaked in a solution of ammonia
(say three parts of water to two parts of ammonia) for an hour or more; after which
it is washed or rinsed in clean water, then boiled in water for an hour or more, then
taken out and dried on a drum, reel or other suitable device, when it is ready for
treatment by the solution herein described.
(3). The solution is composed substantially of the proportions and substances as
follows, namely:-One pound of absolute (or say 99-6) alcohol and three grains of
crystalized iodine and two grains chemically pure aluminium, the latter being in the
shape of thin sheets, filings, chips or grains. The alcohol, iodine and aluminium are
put into an air-tight (Liebig) retort and their temperature slowly raised to say,
170° Fahrenheit and kept so for an hour or more, or until the iodine and aluminium
are entirely dissolved; after which the mixture is allowed to cool, when it should be
placed in an air-tight bottle and kept well scaled from air and moisture, so as to
exclude it from the presence of oxygen. After the solution has cooled down to
15° Fahrenheit, it should have a specific gravity of about 977, and then it is ready
for use.
(4). A portion of the solution is placed in a suitable vessel and the filament or base
5 passed through it slowly; or it may bo immersed or dipped in the solution and then
Iried by the atmosphere or by artificial beat. This process of dipping and drying is
epeated from one to thirty times, or until the desired result is attained; that is, until
he filament or base has become thoroughly impregnated with the substances contained
n the solution; next the filament or base is passed quickly through a strong solution
of chemically pure or practically pure, ammonia, and then immediately the filament or
base must be passed through a weak solution of starch or dextrine and water; aftor
his, and before the filament or base dries, it is passed through a die-plate preferably-

page_text: of sapphire or other hard polished stone. This latter process gives the filament or
base its desired size and forms it into a smooth compact filament, when it is ready for
the fifth step or fusing process.
(5). The filament or base is now formed into the desired shape by winding on
a form or otherwise; it is then placed in a (preferably plumbago) retort with pulverized
plumbago, and the retort cemented or luted air-tight with clay or cement, and the
whole heated in a furnace gradually to from one to four thousand degrees
Fahrenheit, say from three to four hours. This process completoly fuses the iodine
and aluminium into a tenacious filament of iodide of aluminium, while the cotton or
other vegetable fibre or material, having acted as a carrier, former or matrix for the
metallic substances, is partly burnt out and turned into carbon dust, thus leaving a
fibrous skeleton or filament of the metallic compounds as a base for the electro-
deposition in the futuro processes. The furnace and crucible are now allowed to cool
down in their own heat until entirely cool. The filaments or bases may now be taken
out of the crucible and kept in air-tight boxes, excluding the air and moisture until
they are subjected to the 6th step of the process. The filament or base is now mostly
deprived of carbon, being substantially a concentrated fibre of the metallic substances
of the solution, or in the form of an iodide of aluminium, or a metallic fibre of
aluminium and iodine, and is in a proper state or condition to further receive and
combine with the iodine and aluminium in the processes of electro-metallurgy.
(6). This step is a preliminary plating process. After the filament or base has
been cut or formed to the proper length, it is placed in a vessel or bottle con-
taining a portion of the iodine and aluminium solution and a fairly strong current
of electricity passed through it for a few seconds, after which the filament is cut
to the definite length for the size of lamp required and placed or fixed or held in
tongs by the stems or connecting wires; thus the filament is strengthened suffi-
ciently to allow of the handling in the next step.
(7). This is a process of connecting and securing the filament to the terminal or
exterior wires or connections by electro-plating or cementing the joints between
the filament and the metallic conductors by a metallic cement or a metallic deposition
upon the joints from a liquid solution, instead of a cementing by carbon as in the
case of others. When these joints are connected with carbon, or hydro-carbon
compounds, a deposition of carbon is deposited in the joints; this the electric
current soon disintegrates and the lamp-case or bulb is soon blackened inside by
this carbon. This is prevented by my invention, as a metallic cementing is formed
instead of carbon cement. In making this joint, the metal connections at the ends
of the filament are joined together temporarily; the filament having been joined
to the other ends of the wire terminals or tips by holes, tubes or otherwise, the
filament is held by suitable tongs at a distance from the joint desired to be plated
or cemented with the metallic cement; when electrical contact between the source
of the current and the filament has thus been completed, the current is turned on
gently at first, and increased until the joint has been satisfactorily plated over so
as to secure proper contact and officiency in service. The filament is now taken
out and the upper or terminal ends are separated, when it is ready for the next step.
(S). This is a final electro-metallurgy process. The filament is now secured or
held by proper tongs at points just above the cementing point above described,
and proper connections made through the filament and connecting wires to the
electrical source and the current turned on, the filament being enclosed in a vessel
or Blask containing a portion of the iodine and aluminium solution, the air being
exhausted from the flask by means of an air-pump or otherwise, to a barometric
pressure of from 20 to 29 inches. This is for the purpose of excluding the oxygen
in the air during the plating process. The filament is kept in circuit in this
electro-plating bath until the resistance required to give the desired candle-power
is mathematically determined by any suitable apparatus arranged for the purpose;
after which, the current is discontinued, and the filament, after being tested and
regulated for resistance, is ready for use by enclosing in a case in vacuo, or
otherwise.

page_text: (9). This is the finishing and testing process. After the filament has been sub-
mitted to the various steps or processes above described, it is tested carefully to
the standard or unit resistance set for the type of lamp or candle-power desired ;
and should it not come up to this gauge it is returned to the bath and again treated
until it is correct. Then the filament is finished.
It must be understood that the objects for electro-plating in this invention are
entirely different from the objects in other processes heretofore employed, inasmuch
as the others have had for their objects the filling up and hardening of a carbon
filament with carbon from a hydro-carbon liquid; whereas, in this invention, the
object is not that at all; my filament being in a smooth compact form after being
passed through the sapphire die; but the electro-metallurgy is for the purpose of
thoroughly coating the surface of the filament with the metallic substances from the
solution to give endurance to the filament and to reduce a high resistance to a com-
paratively low resistance by means of the coating from the iodine and metallic
compounds taken up by the filament from the solution; a deposition of carbon from
the solution or otherwise, in this case, is positively not desired, as carbon would add
to the resistance I desire to destroy. My filament is comparatively a filament of
low resistance, which is attained by the method and process of electro-plating herein
set forth. My filament is not a carbon filament, as it will be observed that the
various processes it passes through brings it to the state of an iodide of aluminium,
and that the current of electricity passing through the filament causes a further
deposition of a similar metallic nature from the solution to he combined with the
substance of the base and also causes a homogeneous metallic surface to be formed
upon its exterior by the iodide and aluminium or other metallic substances in the
solution.
As have before intimated, various metallic compounds and substances may be
used, and other modes may be employed in producing filaments besides those speci-
fically mentioned herein, and perhaps with some degree of success, but after a very
long and tedious experience in perfecting my present invention, I have arrived at the
best results in the manner and by the methods have fully set forth in this speci-
fication; but I do not confine myself to the proportions and quality stated, nor to the
exact details of treatment, as slight variations might not make very great differences
in practical results.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to
me by my foreign Correspondent I wish it understood that I claim :-
First. In electric lighting, a filament or base, such as described in the first two
notations above stated, when treated and combined according to the processes named
and described in the said two notations, for the purposes stated.
Second. In electric lighting, a filament or base, such as described, when treated and
combined in the manner set forth and described in the several notations above stated,
for the purposes described.
Third. In electric lighting, a filament or base when treated and built up in the
manner described, for the purposes stated.
Fourth. In electric lighting, a filament or base when built up in the manner stated,
said filament or base being composed of the compounds herein before named.
Fifth. In electric lighting, a filament or base built up and composed of aluminium
and iodine in the manner and proportions herein stated.
Sixth. In electric lighting, a filament or base such as described, and built up by
electro-metallurgy in the manner herein set forth.
Seventh. In electric lighting, a filament or base built up by electro-plating from
metallic or semi-metallic substances contained in a liquid solution, substantially as
stated.
Eighth. In electric lighting, a filament or base when formed from metallic sub-
stances in a liquid state and deposited or combined with the base by means of a
process of electro-metallurgy, as, and for the purposes, stated.

page_text: Ninth. In electric lighting, a filament or base built up by electro-plating from a
liquid solution composed of alcohol, iodine and aluminium, substantially in the
proportions stated.
Tenth. In electric lighting, a filament or base when built up from a liquid solution
containing iodine and aluminium, the metallic substances being dissolved by alcohol,
ammonia, or other desirable dissolvent.
Eleventh. In electric lighting, a filament or base built up from a liquid solution of
metallic substances by a process of electro-metallurgy for the purposes of decreasing
the resistance of the said filament.
Twelfth. In electric lighting, a filament or baso built up by metallic substances con-
tained in solution by electro-metallurgy until the electrical resistance of said filament
is brought to the desired mathematical point, as, and for the purposes, stated.
Thirteenth. In electric lighting, a filament or base built up from a liquid compound
of metallic substances by electro-deposition of the metallic substances upon the
filament for increasing its efficiency and durability.
Fourteenth. In electric lighting, a filament or base built up and treated with
metallic substances in a fluid state by impregnation and processes of electro-metallurgy,
substantially as described.
Fifteenth. In electric lighting, a filament or base jointed and cemented to metallic
wires or terminals by a process of electro-metallurgy, by a metallic deposition upon
the joints from a liquid solution, as, and for the purposes, stated.
Sixteenth. In electric lighting, a liquid solution for treating, building up and
cementing filaments, said solution being composed of iodine and aluminium dissolved
in alcohol, ammonia or other dissolvent and deposited on said filament by a process of
electro-metallurgy, for the purposes stated.
Seventeenth. In electric lighting, a liquid solution composed substantially in the
proportion of one pound of alcohol, three grains of crystalized iodine and two grains
of aluminium, the iodine and aluminium being dissolved in the alcohol, thus forming
a metallic compound in solution for the treatment of filaments, as, and for the purposes,
stated.
Eighteenth. The process of forming and building up filaments for electric lighting
by the method and combinations of materials and substances as stated, for the purposes
set forth.
Nineteenth. The process of forming and building up filaments for electric lighting
by the methods and combinations of materials and substances and reducing the
resistance of the filament from a comparatively high to a comparatively low resistance
and mathematically determining the same in the manner specified.
Dated this Sth day of October 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.