IMPROVEMENTS IN THE METHOD OR PROCESS OF MANUFACTURING INCANDESCENT LAMPS AND IN TOOLS OR APPARATUS THEREFOR 33
Year: 1882

page_text: LETTERS PATENT to Alexander Ritchie Leask of 15 Holborn Viaduct in the
City of London for an invention of "IMPROVEMENTS IN THE METHOD OR
PROCESS OF MANUFACTURING INCANDESCENT LAMPS AND IN TOOLS OR
APPARATUS THEREFOR
33
PROVISIONAL SPECIFICATION left by the said Alexander Ritchie Leask
at the Office of the Commissioners of Patents on the 15th April 1882.
ALEXANDER RITCHIE LEASK of 15 Holborn Viaduct in the City of London;
"IMPROVEMENTS IN THE METHOD OR PROCESS OF MANUFACTURING INCANDESCENT
LAMPS AND IN TOOLS OR APPARATUS THEREFOR
"J
I construct what I call a gauge as follows, though I do not bind myself to the
precise materials and forms hereinafter set forth, which merely serve to illustrate
the invention. Two tubes one capable of sliding inside the other may be used and
a block inserted in the free end of each, each block is pierced with a small hole in
the direction of the length of the tubes and binding screws are provided, one to
each block and one to fix the sliding tube at the requisite position There is a
suitable stop in the inner tube between which and the block at its end is a helical
spring. A slot is formed near the end of the inner tube to permit of the binding
screw and block being pushed in, the spring having a tendency to force them out.
An ordinary needle or equivalent is inserted in the hole in each block and block
and needle secured by the binding screw.
The manner of manipulating is as follows: The gauge is adjusted so that its
length exclusive of the needles or points is equal to the length of wire required
for both terminals of a lamp and fixed by the binding screw. The diameter of the
needles should be slightly in excess of that of the filament to be used and the
gauge is now secured in a vice or in some other suitable manner. A coil of soft
platinum or other suitable wire is now taken and one end of it is wound say five
times round the needle, preferably the sliding one which can be moved in against
the spring. The wire is now drawn along the top of the gauge and wound round
the other needle twice the number of times, say in this case ten times. The

page_text: adjustable needle is now pushed in leaving its coil clear which is lifted up and the
other coil withdrawn from its needle and the first needle allowed to spring out
again. The coil of ten is now placed upon the sliding needle the the wire drawn
along the gauge as before and another coil of ten wound upon the fixed needle the
coils again released and the process repeated as often as required. The coils of ten
are now divided in half, the result being a number of lengths of wire with a coil
of five at each end. I now take each wire separately straighten it, bend it to the
required shape hold the spirals in a gas flame until they are red hot and then lay
them aside to cool. I lay the wire upon a flat or grooved surface and insert one
end of a filament into each spiral and with a suitable tool I gently draw on the
spiral lengthwise thereby causing its interior diameter to diminish and grip the
filament, I repeat this with the other spiral and the wire and filament being now
united I call then the "Mounting '
ון
I now take a glass bulb having a neck at one end and an exhausting tube at the
other, place the neck in a blowpipe flame and when sufficiently heated I mould it
to a suitable shape and insert the mounting. 1 again bring the neck into the
flame and compress the sides thereby enclosing both sides of the "Mounting" in
the glass but leaving a central opening between the wires; whilst being enclosed
the Mounting may be adjusted to a central position in the globe The projecting
wire of the Mounting is now severed at the centre and each end is bent round
and inserted in the central opening, the neck again heated and the opening closed
and the glass carefully compressed round the wires of the Mounting leaving two
loops exposed and the lamp is now ready for being exhausted and finished off in
the usual way.
One gauge I have made is of square brass tubing but it may be round or
otherwise if preferred and of any suitable material.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Ritchie Leask in the Great Seal Patent Office on
the 14th October 1882.
ALEXANDER RITCHIE LEASK of 15 Holborn Viaduct, in the city of London
"IMPROVEMENTS IN THE METHOD OR PROCESS OF MANUFACTURING INCANDESCENT
LAMPS AND IN TOOLS OR APPARATUS THEREFOR
This Invention consists of an improved process and tools for the manufacture
of Incandescent Electric Lamps and may be described as follows, taking the tool
first, viz.
I I construct a tool or Guage Fig 1 in the following manner; O is a square
brass tube, K* is a block of brass fitting into O and has a hole drilled through it
parallel to, and at a suitable distance from its upper surface. This hole is drilled
large enough to receive an ordinary sewing needle or its equivalent such as a fine
steel wire as shewn at P. B³ is a binding screw which passes through a hole in
the underside of O, through the screwed hole shown in K and serves both to
retain the block K2 in its place, and to secure the needle P2 in any desired position
I is also a square brass tube fitted to slide easily in O. K' is a block of brass
similar to K fitted to slide easily in I, and has a holo drilled through it in like
manner as shown at P¹. The spiral spring A made of brass wire, and inserted in
tube I presses against block K' at the one ond and against a stop or pin D fastened
in the tube I at the other end. B' is a binding screw which passes through a
longitudinal slit I as shewn in under surface of tube I and through the screwed
hole shown in K¹, and serves both to keep the block K' from being forced out of I
by the spring H, and to secure the needle P¹ in any desired position. The slit in
under surface of tube I is th of an inch, more or less according to circumstances,
in length and its width is sufficient to allow free movement of the screw B¹. By
pushing the screw B' along the slit towards B2 the block K¹ is drawn into the
tube I carrying with it the needle P¹ and by releasing B¹, the spring H forces the
block K' and needle P' outwards into their former positions. B is a binding
screw passing through the screw hole shown in A which is a piece of brass
soldered on to the under surface of tube O or part of the tube itself if thick
enough and serves to secure the tube I in any desired position
III adjust the guage (Fig 1) so that its length from X to Y is equal to the
length of wire required for both terminals (exclusive of the spirals presently to bo
described) of a lanp, and having secured it by the screw B² I insert at each end or
they may be previously inserted as at P1 and P (Fig 1) an ordinary sewing needle
or its equivalent of a diameter slightly larger than that of the filament to he used,
and allowing their ends to project a suitable distance, secure them by the screws B¹
and B. The Guage being now ready for use is securely fastened in a vice, or in
some other convenient manner.
III I take a coil of soft platinum, or other suitable wire and twist one end of it
around the left hand needle P¹ (Fig 1) say five times in a spiral fashion and leave
it there 1 then draw the wire along the top of Guage from X to Y and twist it
around the right hand needle P, say ten times in a spiral fashion as before; I push
the screw B towards the right in the drawing whereby the needle P is with drawn
and the spiral form on the end of the wire is released. I then draw the spiral
formed at P off its needle, and releasing the scrow B', the spring H sends the
block K' and needle P' into their former positions. I place the spiral which was
formed at P upon the needle Pl. I draw the wire along the top of Guage from X
to Y and twist it around the right band needle P' ten times as before. I again

page_text: push along the screw B' release the spiral on needle P withdraw that on P³, and
place it on P¹ ns before, and continue in the like manner forming spirals of the
wire upon the right hand needle P until the wire is used up or the required
number of terminals made, As the last spiral will not need to bo cut it inny
have only five turns the exact number of turns in the spirals may vary, as 5
4 and 8, and 12 el catera but in ordinary cases 5 and 10 aro suitable.
IV The wire being now measured off and spirals formed upon it at equal
distances I cut the first spiral of ten turns and every subsequent spiral except the
last of all through the centre. This cuts up the wire into pieces of equal length,
each piece having at each of its ends a spiral of five turns. These pieces I call the 1
"wires."
VI take each "Wire "separately-straighten it—bend it into the form shown at
Fig 2 or other suitable form and hold the spirals in a gas flame until they are red
hot then lay them aside to cool.
VII lay the wire upon a flat surface, the ends pointing towards the right and 1
hold it securely with the left hand. With the right hand 1 take up a filament,
and insert one end of it into each of the spirals and leave it there. I then take a
thin blunt instrument in the right hand and inserting it between the outer and
second coil of one spiral by gently moving the blade towards the right, I stretch
the spiral in that direction thereby causing its internal diameter to diminish until
the filament is securely grasped by it; I repeat this with the other spiral and the
Wire" and filament being now united 1 call them the "Mounting" (See enlarged
View Fig 6)
"1
VIII now take a glass bulb. preferably, though not necessarily, of the form
shewn at Fig 3 in which B is the bulb, N the neck, and X the tube for exhausting
and holding it by the tube X I bring the neck N into a blow pipe flame and when
sufficiently heated I mould it with a pair of forceps into the form shewn at M. H
Fig 3 withdraw the neck N from the flame and insert the "Mounting" into the
bulb allowing it to rest there as shown at F. S. W Fig 3.
41
VIII I bring the neck N again into the flame and heating it sufficiently I 3
compress each side of it with forceps thereby enclosing both sides of the
Mounting" in the glass, but leaving an opening in the centre of it between the
two enclosed wires of the "Mounting." By the same application of the forceps
while being enclosed in the neck, tho" Mounting" is brought into a central position
in the bulb, and is then as shown in Fig 4.
IX The wire of the 1
Mounting" is sovered at W Fig 4 and with a pair of
round nosed plyers each end is bent round and inserted in the central opening left
in neck N as shown in Fig 5. The neck being again sufficiently heated the forcops
are used to close the opening and compress the glass carefully around the now
separate terminal wires. When this has been done the lamp is ready for being
exhausted and finished off in the usual way.
I have so far described one way of carrying out my invention but it will be
understood that reasonable modifications may be made without departing from the
spirit of it. For instance the size shape and materials of the guage Fig 1 the
exact form of the "Wire" Fig 2 or the bulb Fig 3 or the movements described 4
in VI can all be varied as found desirable to suit circumstances. In Fig 5 the
ends T of the divided wire are turned inwards towards each other, but it is
evident that they can be turned outwards from each other if required In ordinary
practice howevor I prefer to turn them inwards as shown. Again, in contracting
the internal diameter of the spirals I have described the method which I have by
experience found to be most satisfactory but other means might be adopted such
as opening out the coils by the use of a pair of plyers or compressing them bodily
in suitable dies
Having now described my invention and the method of performing the same
I wish it to be understood that I am aware that the use of a spiral for joining the 5
wires to the filament is not now and I make no claim thereto separately.
Heretofore spirals have however been used as tubes or sockets into which the

page_text: ends of the filament were placed and secured therein by electro plating Indian or
Chinese Inks, wedges and so forth and in fact in most cases a solid shelled tube
would have done just as well-In some cases independent spirals have been used
ns sockets into which both the filament and the wire were inserted and secured
What I claim and desire to protect under the hereinbefore in part recited Letters
Patent is ;
First In the manufacture of terminals for Incandescent electric lamps the
employment of a tool or guage shown in Fig 1 of the accompanying drawings
constructed and used substantially as and for the purposes herein before described.
Second-The construction and mode of manufacture of Incandescent electric
lamps wherein a single piece of wire is employed to form both terminals being
subsequently divided and forming two separate and independent terminals
substantially as and for the purposes herein before described
Third As a means of connecting the terminal and filament of Incandescent
electric lamps the formation of the end of the terminal wire into a spiral which by
the elongation of the said spiral or separation of its coils or otherwise contracting
its internal diameter is caused to grip the filament substantially as and for the
purposes herein before described.
In witness whereof I the said Alexander Ritchie Leask havo hereunto set
my hand and seal this fourteenth day of October in the Year of Our
Lord One thousand eight hundred and eighty two.