An Improved Process of Manufacturing Electric Incandescent Lamps.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
An Improved Process of Manufacturing Electric Incandescent Lamps.
We, CHARLES HOWARD, Gentleman, of VII Lerchenfelderstrasse 67, and
Dr. RICHARD MAYER, Engineer, of II Taborstrasse, 18, both of Vienna, in the
Empire of Austria, do hereby declare the nature of this invention to be as
follows:-
Hitherto used or spent incandescent lamps have been practically useless, and
this invention relates to a process of manufacturing lamps of this kind which are
in every respect equal to those hitherto made and have the additional advantage
that after they have been used only the filaments require renewal, the remaining
portions of the lamp being capable of further employment.
The method of carrying out the invention is as follows;
A wire frame not yet provided with a filament is fixed into a glass tube, which
is about 3 to 5 centimetres long. To one of the ordinary filaments two pieces of
wire are fastened in the known manner, such wire being of platinum or nickel
for example; these pieces of wire are then connected with the ends of the fused-
in frame, this connection being made by soldering with copper, by means of
binding screws or in any other appropriate manner, although we have found the
following to be a ready and advantageous manner of effecting this. Closely coiled
spirals of spring wire are taken and these are stretched out either by means of
two pliers or by hand until the ends of the wire can be inserted therein whereupon
the spring is allowed to resume its initial position, thereby automatically clamping
and holding the ends of wire.
The bulb is then fused on to the free end of the glass tube, or this connection
may be effected by means of cement or in any other suitable manner. The
lamp is exhausted in the customary manner, then removed from the pump and
provided with a base.
A further object of this invention is the provision of a specially suitable base.
A base made in the usual manner is provided with slots and the neck of the
lamp is formed with projections, which, when the base is passed upon the neck of
the lamp fit into such slots. In order to fix the bulb immovably to the base a wire
or band is placed upon the upper edge of the neck, whereupon by drawing together
the wire or band the base is pressed against the neck, so that the said base remains
fixed. The base may instead of course be provided with recesses or indentations
in which case the neck must also be provided with corresponding indentations and
the base may if desired be larger than the neck so that by pressing the base into
an oval form, bringing the indentations in the base over those in the glass neck and
then releasing the base so that the projections formed by the said indentations
spring into the indentations on the glass; in this case likewise a wire or band
may be used in order to press the base upon the glass.

page_text: If, when the filaments of such a lamp has been broken, it is desired to re-fit it
with a new one, it is only necessary to take the lamp to pieces, preferably at the
neck; for example the old filament is detached, a new one inserted and the parts
again assembled. It should however be pointed out that these lamps require a
longer neck than is usual, because on fusing the bulb to the glass tube, the glass
becomes heated, and if the neck were short the base or its solder or cement might
be injuriously affected by the heat. Our method of constructing the base above
described is especially adapted for commercial or business purposes as it is not so
liable to become damaged as the forms of base hitherto employed.
This process likewise has special advantages from a manufacturing point of
view, because the waste arising during the manufacture itself, which is frequently
very considerable, may be utilised by merely detaching the bulb, so that only the
filament is lost.
Dated this 13th day of Octabon 1807
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
improvements in Electric Incandescent Lamps.
We, CHARLES HOWARD, of 345, Fulham Road, S.W., in the County of London,
late of VII Lerchenfelderstrasse 67, Vienna, in the Empire of Austria, Gentle-
man, and Dr. RICHARD MAYER, Engineer, of II Taborstrasse 18, Vienna, in the
Empire of Austria, 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 electric incandescent lamps and has for its chief object
to construct such lamps so that they can be repaired in a very simple and inax-
pensive manner after the filaments become broken.
A further object is to provide caps of a kind which can be effectually secured
to the lamp without the use of cement.
According to the said invention the bulbs are provided with elongated or tubular
necks which instead of being blown in one piece with the bulb are connected
thereto by fusing or otherwise, so that the said neck can be readily cut or divided
along the line of contact to enable a broken filament to be removed and replaced
by a fresh one.
The said filament instead of being secured directly to the terminal wires, is
attached to two short lengths of wire distinct from the said terminal wires, and
means are provided whereby these short lengths of wire can be readily connected
to or detached from the corresponding terminal wires, thus securing the advantage
of a wire to wire connection only being required when the filament is to be secured.
in place and obviating the use of paste, cement or the like.
The caps above referred to are formed substantially in the manner usual with
caps having a central terminal but are adapted to be secured in position by wires,
bands or the like tied tightly around them and engaging small projections or
bosses of the neck of the lamp.
In order that the invention may be clearly understood and readily carried into
effect I will proceed to describe the same fully by aid of the accompanying
drawings in which:
Figure 1 is a vertical central section of one construction of lamp according
to the invention.

page_text: Figure 2 is a part section showing the filament and its connections separate
from each other.
Figure 3 is a detail view in elevation showing the mode of securing the cap
to the lamp.
Figure 4 is a perspective view of the cap detached.
Figures 5 and 6 are detail views in side view and enlarged cross section of a
modified arrangement for connecting the terminal wires and the wires to which
the filament is attached.
Figure 7 is a side view showing another arrangement in which a spring is
employed for effecting this connection.
a is the bulb of the lamp and a is the elongated or tubular neck thereof which
consists of two parts fused together around their line of contact a².
The main purpose of making the neck in this way is so that on account of its
length and comparatively small diameter the two parts thereof can be readily
separated by cracking or cutting the neck on the line a², say by means of a hot
wire, and can afterwards be fused together without injuring the terminal wires
where they pass through the glass.
bb are the terminal wires which constitute the wire frame" referred to in
my Provisional Specification, and c is the filament of the lamp.
It will be seen that this filament instead of being secured directly to the said
terminal wires, is secured to a pair of short wires d of platinum, nickel or other
suitable metal, which are held together by a small bead of glass d', the affixing
of the filament to these short wires being effected prior to the insertion thereof
in the lamp, thus rendering the manipulation much simpler than that required
in cases where the filament has to be secured to the wires whilst inside the bulb
in the ordinary manner. A supply of filaments thus attached to wires d
instance be kept in stock ready for insertion in the lamps.
may for
The means for connecting the wires d to the terminal wires b, in such a manner
that they can be readily detached therefrom comprise, in the example in question,
two capillary tubes e e of copper or other suitable metal. These tubes are adapted
to fit tightly on the ends of the terminal wires, and their free ends serve as sockets
to receive and retain the ends of the short wires carrying the filaments; the
tubes e e thus provide an efficient mechanical and electrical connection without
resorting to any fusing or soldering of the ends together, while such connection
can however be readily detached if desired by simply drawing out the short
wires d.
Supposing the lamp.to have been in use and the filament to have been broken,
it is only necessary to crack the glass around the line a² and to separate the part
carrying the terminal wires and filament from the bulb, thus withdrawing the
filament from the latter. It is then only necessary to withdraw the short wires d
from the capillary tubes and to insert therein the corresponding wires of a new
filament. The two parts of the neck can then be fused together again on the
line a³, and the lamp be re-exhausted, which latter operation can be performed in
a manner which will be readily understood by breaking the tip or point a³ of the
lamp.
f is the cap of the lamp, or rather the outer metallic portion or shell of the
said cap, being the central terminal thereof and the insulating material in
which the said terminal is set. It will be seen 'that the shell f is formed with
a screw-threaded surface so that it can be readily secured in a holder in the
ordinary manner.
In my Provisional Specification I have termed this cap the “base” but it will
be obvious that the term is employed only in the same sense as I now use the term
cap, that is to say, to indicate the part which serves to secure the lamp to its
holder.
The connection between the cap and the lamp is effected by means of a wire f
in the following manner:
In the closed end a of the neek of the lamp are formed two small projections

page_text: or bosses a which are adapted to enter two notches or recesses f in the lower
edge of the cap, so that the said edge extends beyond these projections or bosses
and rests upon a collar or shoulder a
The wire is then passed around the cap and twisted up tightly below the
said projections so as to press the lower edges of the cap tightly against the glass.
The corners f of the notches f* are next turned or bent up over the said wire,
which being thus in engagement both with the projections f and with the cap,
serves to lock the latter securely to the lamp.
It will be seen that with a cap or base of this kind no cementing is required
and that it can be very readily replaced when desired. The importance of using
such a cap or base in combination with a divisible and rejoinable neck in a renew-
able lamp is obvious. If ordinary cemented caps were used there would be a great
danger of the connections or joints being destroyed by the heat employed in
rejoining the neck and of the cement also being injured. Such danger is avoided
in my invention. Further, should the closed end of the neck be accidentally
injured the cap can be readily detached therefrom and placed upon a new neck.
From these points great economy results.
According to the modification shown in Figures 5 and 6, the capillary tubes e
are dispensed with and the connection between the wires d and terminal wires b
is effected by means of a small collar 9 having an approximately oval passage or
opening in which the ends of the wires are placed and wherein they are secured
by means of a tapered pin g¹ passed transversely through the collar and
jammed between the two wires thus providing the desired electrical and
mechanical connection.
Obviously a connecting device consisting of two clamping blocks held tightly
togother by a screw or rivet so as to grip the ends of the wires may be employed
instead of the collar if desired.
In the arrangement shown in Figure 7 the connection between the terminal
wires and the short wires attached to the filament is effected by means of fine
coiled springs which take the place of the capillary tubes above referred to.
The advantage of these springs is that they possess a greater amount of flexibility
than the said tubes. In other respects the arrangement is substantially the
same as those hereinbefore described.
The several means for attaching the terminal wires b, b, to the other or auxiliary
wires d, d, are well known and are here shown merely as being suitable for the
purposes of this invention.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:-
1. The combination in a lamp of the kind referred to viz, an electric incandescent
lamp provided with an elongated or tubular neck consisting of two parts capable
of being disconnected and rejoined, of a cap having slots or recesses
embracing projections on the neck of the lamp, and a wire or the like which
holds it in position thereon, substantially as described.
2. The combination in a lamp of the kind referred to of a cap having slots or
recesses embracing. projections on the neck of the lamp, and a wire which holds it
in position thereon, the said wire acting in conjunction with the turned or bent
up corners f, substantially as described.
3. An incandescent electric lamp constructed substantially as hereinbefore
described with reference to Figures 1 to 4 inclusive.
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.