IMPROVEMENTS IN THE MANUFACTURE OF INCANDESCENT ELECTRIC LAMPS
Year: 1882

page_text: LETTERS PATENT to The Honorable Reginald Brougham and Frederic
Aldridge Ormiston both of Heddon Street Regent Street in the County
of Middlesex, for an invention of "IMPROVEMENTS IN THE MANUFACTURE
OF INCANDESCENT ELECTRIC LAMPS
13
PROVISIONAL SPECIFICATION left by the said Reginald Brougham and
Frederic Aldridge Ormiston at the Office of the Commissioners of Patents
on the 8th April 1882.
"
The Honorable REGINALD BROUGHAM and FREDERIC ALDRIDGE ORMISTON
both of Heddon Street Regent Street in the County of Middlesex.
MENTS IN THE MANUFACTURE OF INCANDESCENT ELECTRIC LAMPS "
IMPROVE-
At the present time incandescent electric lamps are commonly made of a hollow
glass globe or sphere with a hollow cylindrical stem standing out from it and
closed at its outer end. The conducting wires pass through this closed end and
inside the globe carry a carbon filament one end of the carbon filament being
connected to one wire the other to the end of the other wire. These glass spheres
have been exhausted of air and the exhaustion has been effected through a small
tube attached to them. By reason of the way in which the ends of the cylindrical
stems have been closed and the way in which the conducting wires have been
passed through them the small tube through which the globe has been exhausted
has necessarily been sealed on to some part of the globe itself and not to the end
of the cylinder By our system of manufacture we avoid this necessity and are
able to attach the small tube used for exhausting the globe to the closed end of
the cylindrical stem thereby improving the appearance of the lamp as well as
attaining other advantages.
Our improvements also relate to improved means of sealing in the wires where
they pass in through the closed end of the cylindrical stem and also to improved
ineans of securing the extremities of a carbon filament to the extremities of the
conducting wires.

page_text: We first take a glass tube and after sealing over one of its ends blow out the
closed end to form it into a globe or sphere and cut off the tube near to the sphere
so as to leave the sphere with a short length of tube projecting from it. We then
take another length of the same sized tube and draw down its two ends-one of
the drawn down ends is flattened so as to make it of an oblong form in cross
section with two flat sides parallel and near to one another. The end of the 'tube
is then cut off at a point where the tube is thus reduced to an oblong form. The
two conducting wires are now passed through the oblong opening at the end of the
tube and this end is heated and whilst heated the two flattened sides of the oblong
end are closed together by a pair of tongs to weld them together whilst at the
same time a perfect sealing of the joint is effected by blowing through the opposite
end of the tube. Where the wires are to be enclosed between the two flat sides
of the oblong end of the tube the wires have previously given to them a coating
of glass which will weld to the flat sides of the glass tube when they are heated
and pressed together. A small tube is now sealed on to the closed end of the tubo
near to one or other side of the closed flattened oblong portion above mentioned.
The glass tube is cut to the requisite length and the carbon filament is attached
to the ends of the conducting wires. The cut end of the tube is placed against the
end of the cylindrical stem projecting from the hollow sphere and the two are
welded or blown together. The interior of the sphere is then exhausted through
the small tube and when exhaustod this tube is sealed off close to the end of the
cylindrical glass sphere.
To connect the ends of the carbon filament to the ends of the conducting wires
we form a flattened surface on one side of each wire near its end and slip on to
each wire conductor a small coil of thin wire which will clip and embrace it, we
then place one end of the carbon filament against the side of one of the conducting
wires where it is flattened and reduced in thickness and then slip the wire coil
over the end of the filament so that it embraces and nips both the wire and the
filament and holds them together-The other ond of the filament is then similarly
connected to the other conducting wire.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Reginald Brougham and Frederic Aldridge Ormiston in the Great
Seal Patent Office on the 7th October 1882.
The Honorable REGINALD BROUGHAM and FREDERIC ALDRIDGE ORMISTON both
of Heddon Street Regent Street in the County of Middlesex IMPROVEMENTS IN
THE MANUFACTURE OF INCANDESCENT ELECTRIC LAMPS
"
At the present time incandescent electric lamps are commonly made of a hollow
glass globe or sphere with a hollow cylindrical stem standing out from it and
closed at its outer end. The conducting wires pass through this closed end and
inside the globe carry a carbon filament one end of the carbon filament being
connected to one wire the other to the end of the other wire. These glass spheres
have been exhausted of air and the exhaustion has been effected through a small
tube attached to them. By reason of the way in which the ends of the cylindrical
stems have been closed and the way in which the conducting wires have been
passed through them the small tube through which the globe has been exhausted
has necessarily been sealed on to some part of the globe itself and not to the end
of the cylinder. By our system of manufacture we avoid this necessity and are
able to attach the small tube used for exhausting the globe to the closed end of the
cylindrical stem thereby improving the appearance of the lamp as well as attaining
other advantages.
Our improvements also relate to improved means of sealing in the wires where
they pass in through the closed end of the cylindrical stem and also to improved
means of securing the extremities of a carbon filament to the extremities of the
conducting wires.
We first take a glass tube and after scaling over one of its ends blow out the
closed end to form it into a globe or sphere and cut off the tube near to the sphere
so as to leave the sphere with a short length of tube projecting from it, or what is
better we at once blow a globe or sphere with a tubular neck projecting from it
and cut this neck to the length required. We then take another length of the
samé sized tube and draw down its two ends one of the drawn down ends is
flattened so as to make it of an oblong form in cross section with two flat sides.
parallel and near to one another. The end of the tube is then cut off at a point
where the tube is thus reduced to an oblong form. The two conducting wires are
now passed through the oblong opening at the end of the tube and this end is
heated and whilst heated the two flattened sides of the oblong end are closed
together by a pair of tongs to weld them together whilst at the same time a perfect
sealing of the joint is effected by blowing through the opposite end of the tube.
Where the wires are to be enclosed between the two flat sides of the oblong end of
the tube the wires have previously given to them a coating of glass which will
weld to the flat sides of the glass tube when they are heated and pressed together.
A small tube is now sealed on to the closed end of the tube near to one or other
side of the closed flattened oblong portion above mentioned. The glass tube is cut
to the requisite length and the carbon filament is attached to the ends of the
conducting wires. The cut end of the tube is placed against the end of the
cylindrical stem projecting from the hollow sphere and the two are welded or
blown together. The interior of the sphere is then exhausted through the small
tube and when exhausted this tube is sealed off close to the end of the cylindrical
glass sphere.
To connect the ends of the carbon filament to the ends of the conducting wires
we form a flattened surface on one side of each wire near its end and slip on to

page_text: each wire conductor a small coil of thin wire which will clip and embrace it, we
then place one end of the carbon filament against the side of one of the conducting
wires where it is flattened and reduced in thickness and then slip the wire coil
over the end of the filament so that it embraces and nips both the wire and the
filament and holds them together. The other end of the filament is then similarly
connected to the other conducting wire. We may in addition further secure the
joint by applying around it a cement composed of a mixture of iron filings sulphur
and salamoniac such as is commonly used as a cement for filling spaces in iron
work constructions and the composition of which is well understood.
In order that our invention may be fully understood wo have illustrated in the
Drawings hereunto annexed the various stages of the above described process of
manufacture of an incandescent electric lamp..
Figure 1 shews a glass globe or sphere with a short neck which may be blown
in the ordinary manner with a long neck and the neck can then be cut to the
length required.
Figure 2 shews a length of glass tube of the same diameter as the neck which
has been drawn down at two points A. B. at a distance from one another. One of
the drawn down ends say the end A is flattened to an oval form in cross section as
shewn at Figure 3 and the end is cut across where it is thus flattened say on the
line a. b.
Two conducting wires C which have each been coated for part of their length
with a coating of glass O', are passed into the oval end and their outer coating of
glass is made to adhere to the oval end so as to hold them in the position shewn
at Figure 4. The end is then heated and closed by nipping together its flattened
sides. It is then again heated and its end effectually sealed by wind pressure
applied through the drawn down end B. The end A will then appear as shown in
section at Figure 5, afterwards a small glass tube D is sealed to the rounded
portion of the end as shown at Figure 6. The tube might then be cut say at the
line c. d. and when a carbon filament had been attached to the ends of the con-
ducting wires in any suitable manner the tube might be joined on to the end of
the tubular neck of the globe or sphere shewn at Figure 1. The lamp would then
have the appearance shewn at Figures 7 and 8.
In place however of at once cutting the tube on the line o. d. we prefer to flatten
the drawn down end B and cut it off where so flattened then seal two conducting
wires into it as proviously described with reference to the end A and also seal on
to it a tube D. In this way two necks or ends with conducting wires sealed into
them are obtained each suitable for being joined on to the end of the tubular neck
of a globe or sphere, such as shown at Figure 1.
The next operation is to exhaust air from the interior of the spheres through the
tubes D-this is effected in the ordinary way and when the operation has been
carried on long enough the tube D is sealed off close to the end of the tubular
stem and the portion of tube shewn by dotted lines in Figures 7 and 8 is removed
leaving the lamp completed in the forin shewn by the full lines in these Figures.
At Figures 9 and 10 we have shewn how we connect the ends of a carbon
Bilament to the ends of the conducting wires. Each wire near its end is filed away
on one side and a small coil of thin wire E is slipped onto the conducting wire as
shewn on an enlarged scale at Figure 9.
An end F of the carbon filament is then held against the side of the conducting
wire where it has been filed away and the small coil E is slipped over it as shewn
at Figure 10 it then clips and holds the filament to the conducting wire.
The small coil E where it embraces the filament and wire is then coated with a
composition consisting of a mixture of iron filings, sulphur and salamoniac for the
purpose of filling the interstices contained in the coil and the spaco surrounding
the filament and wire at that point so that a more intimate union and consequently
better electrical contact may be made between the said filament and wire. It is
not essential to use an outer coating of iron cement at the joint but by its use a
more perfect joint is made.

page_text: Having thus described the nature of our Invention and the manner of performing
the same we would have it understood that we claim :—
First. The manufacture of incandescent electric lamps substantially in the
manner herein before described.
Second. Connecting the ends of a carbon filament to the ends of conducting
wires in the manner herein before described.
In witness whereof I the said Frederick Aldrige Ormiston have hereunto set
my hand and seal this seventh day of October in the year of our Lord One
thousand eight hundred and eighty two.
FRED. ORMISTON. (L.S.)