IMPROVEMENTS IN ELECTRIC LAMPS OR LIGHTING APPARATUS
Year: 1881

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for an Invention
of "IMPROVEMENTS IN ELECTRIC LAMPS OR LIGHTING APPARATUS." A com-
munication from abroad by Joseph V. Nichols, of Brooklyn, New York,
United States of America.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at
the Office of the Commissioners of Patents on the 21st July 1881.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent
"IMPROVEMENTS IN ELECTRIC LAMPS
Agents, Southampton Buildings, London.
OR LIGHTING APPARATUS." [A communication from abroad by Joseph V. Nichols,
of Brooklyn, New York, United States of America.]
This Invention relates to electric lighting apparatus of that class known as
incandescent lamps, and comprises improvements in the manner of forming the
enclosing globe, sealing the metallic conductors into the same, and attaching the
carbons to the end of the wires.
As usually constructed the enclosing globe or receiver containing the incandescent
carbon conductors has a projecting neck or a solid mass of glass containing the
conducting wires and sealed into an opening in the globe. The shape of the
lamps is thus rendered very uneven, the lamps themselves are expensive and very
liable to be broken. It is the object of the present Invention to do away with
these necks entirely, and for this purpose the wires are first embedded in a small
circular disc of a vitreous cement, or in other words, a composition of potash,
silica, and oxide of iron and copper. This disc is sealed directly into the opening
of the main globe by the aid of a blow-pipe, and the exterior surfaces of the two
made smooth and even, so that no projections are left which are liable to be
broken in handling or in transportation, while a perfect union and air-tight joint
is secured between the glass and the conducting wires, even when the latter are of
copper.
The joint will be rendered more durable and perfect by causing the vitreous

page_text: cement to cover the wires for a short distance above the main mass or interior
surface of the disc.
A lamp made according to this Invention is constructed as follows, that is to
sayThe metal conductors are embedded in a mass of vitreous cement, the wires
being also coated with the same material for some distance above the main mass.
The conductor of carbon is then mounted on the projecting ends of the wires, and
the whole inserted in an opening in the globe and welded to the edge of the said
opening and the exterior surface rounded off and made even.
It has heretofore been customary in the manufacture of this kind of lamp to
blow out a globe spherical or approximately so in shape, which operation requires
the highest skill and produces a very delicate and fragile globe. In order to avoid
these objections in the formation of the lamps, I take an ordinary tube of glass
and form therefrom the receiver by heating and mouldings over one end to unite
it to the vitreous material surrounding the wires, and pressing in the edges of the
other end in the same manner until they nearly mect, when they are drawn out
into a tube by which the cylinder is exhausted and sealed up. Instead of a
spherical globe a cylinder with rounded ends is thus formed, which possesses many
advantages over other forms from the fact that it is stronger and more compact,
and that its shape allows a great number to be conveniently packed for trans-
portation without danger of breaking. A lamp thus made has also the advantage
from its peculiar shape of being better able to withstand the atmospheric pressure
when the air has been exhausted from its interior.
To connect the carbon conductor to the ends of the metal wires clamps are
employed. The carbon conducting strip is made in the usual manner. with
widened ends. These strips are by preference prepared by carbonizing blanks cut
from a sheet of paper, the form of the blank being approximately that of the
finished conductor. This method is not essential, however, as other may be
employed in the preparation of the carbons as by bending and twisting straight
strips of wood or paper either before or after carbonization.
Through the ends, square or rectangular perforations are made before carbon-
ization, and through these perforations the flattened ends of the wires or conductors
are passed and bent over by pincers to firmly clamp the carbon. In order to secure
a more perfect electrical contact between the carbons and the wires, the ends of
the former may be previously coated with copper or platinum, or after being
clamped together the joints may be perfected by immersing them in an electro-
plating bath, and depositing copper or nickel on and around the same. With this
form of clamp all nuts, screws, or pins and similar accessories are dispensed with.
The-conductors.make.contact-with-the-carbons-at-considerable-distance-from-the-
incandescent portion, so that the permanency of the connections is ensured, and as
the wires are by this means protected in great measure from the heat developed
they may be of copper, whereby the cost of the lamp is greatly reduced.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the
20th January 1882.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent
Agents, Southampton Buildings, London. "IMPROVEMENTS IN ELECTRIC LAMPS
OR LIGHTING APPARATUS." A communication from abroad by Joseph V. Nichols,
of Brooklyn, New York, United States of America.
This Invention relates to incandescent electric lamps, and comprises improve-
ments in the manner of forming the enclosing globe, sealing the metallic
conductors into the same, and attaching the carbons to the end of the wires.
As usually constructed the enclosing globe or receiver containing the incan-
descent carbon conductors has a projecting neck or a solid mass of glass containing
the conducting wires, and sealed into an opening in the globe. The shape of the
lamps is thus rendered very uneven, while the lamps themselves are expensive and
very liable. to be broken. It is the object of the present Invention to dispense with
these necks entirely, and for this purpose the wires are first embedded in a small
circular disc of a vitreous cement, or in other words a composition of potash, silica,
and oxide of iron and copper. This disc is sealed directly into the opening of the
main globe by the aid of a blow-pipe, and the exterior surfaces of the two parts
are made smooth and even, so that no projections are left which are liable to be
broken in handling or in transportation, while a perfect union and air-tight joint
are secured between the glass and the conducting wires even when the latter are
of copper.
The joint will be rendered more durable and more nearly perfect by causing the
vitreous cement to cover the wires for a short distance above the main mass or
interior surface of the disc.
The said Invention is illustrated in the accompanying Drawing, in which
Figure 1 is an exterior view of one of my improved lamps mounted in a holder
ready for use, and
Figure 2 is a central section of the said lamp.
Figure 3 is a central section shewing the conductors connected with the carbon
enclosed in a mass of vitreous cement, as hereinafter described.
.
Figure 4 is a vertical section of an ordinary form of lamp hereinafter
referred to.
Figure 5 is a face view.
Figure 6, an edge view, and
Figure 7 a perspective view representing a method, hereinafter described, for
connecting the carbon conductor to the ends of the metal conductors or wires by
clamps.
Referring to Figures 1, 2, and 3; C, C, are the metal conductors, which are
shown embedded in a flat circular mass B of vitreous cement, the wires being also
coated with the same material for some distance above the main mass. The
conductor D of carbon is then mounted on the projecting ends of the wires, and the
whole is inserted in an opening in the globe A and welded to the edge of the said
opening, and the exterior surface is rounded off and made even.
It has heretofore been customary in the manufacture of this kind of lamp to
blow out a globe spherical or approximately so in shape, which operation requires
the highest skill and produces a very delicate and fragile globe. In order to avoid
these objections in the formation of the lamps, I take an ordinary tube of glass
and form therefrom the receiver by heating and moulding over one end to unite
it to the vitreous material surrounding the wires, and pressing in the edges of the
other end in the same manner until they nearly meet; they are then drawn out
into a tube by which the cylinder is exhausted and sealed up. Instead of a
spherical chamber or globe, a cylinder with rounded ends is thus formed, which
possesses many advantages over other forms for the reasons that it is stronger and

page_text: more compact, and that its shape allows a great number to be conveniently packed
for transportation without danger of breaking. The said lamp has also the
advantage by reason of its peculiar shape of being better able than other lamps to
withstand the atmospheric pressure when the air bas been exhausted from its
interior, the usual form which is illustrated in Figure 4 not possessing this quality
to such a degree.
To connect the carbon conductors to the ends of the metal conductors or wires,
the clamps shown in Figures 5, 6, and 7 are employed.
In these Figures A represents a carbon conducting strip made in the usual
manner with widened ends B, B. These strips are by preference prepared by
carbonizing blanks cut from a sheet of paper, the form of the blanks being
approximately that of the finished conductor. This method of preparation is not
essential, however, as others may be employed in the making of these carbons, such
as bending and twisting straight strips of wood or paper either before or after
carbonization.
Through the ends B, B, square or rectangular perforations are made at c, c,
before carbonization, and through these perforations the flattened ends of the wires
or conductors D, D, are passed, the same being bent over by pincers to firmly
clamp the carbon. In order to secure a more perfect electrical contact between
the carbons and the wires the ends of the former may be previously coated with
copper or platinum, or after being clamped together the joints may be perfected by
immersing them in an electro-plating bath, and depositing copper or nickel on and
around the same. With this form of clamp all nuts, screws or pins, and similar
accessories are dispensed with. The conductors make contact with the carbons
at a considerable distance from the incandescent portion, so that the permanency
of the connections is ensured, and as the wires are by these means protected in a
great measure from the heat developed, they may be of copper, whereby the cost of
the lamp is greatly reduced.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and shown how the same may be conveniently and
advantageously carried into practice, I claim,-
First. An incandescent electric lamp consisting of an exhausted glass cylinder
with rounded ends made as described, and having the metallic conductors sealed
therein, substantially as set forth.
Second. An incandescent electric lamp consisting of an exhausted glass cylinder
with rounded ends, and containing a carbon conductor attached to metallic con-
ductors or wires passing through a mass of vitreous material which is united with
the said cylinder in such a manner as to leave_an_even_external surface, as above
set forth.
Third. The combination in an incandescent lamp with the perforated ends of a
carbon conducting strip of metallic conductors or wires passing through the same
and bent over into close contact with the carbon, as above described.
Fourth. The combination with the carbon conducting strip A, Figures 5, 6, 7,
having the widened portions B, B, and the rectangular perforations at C, C, of the
conducting wires D, D, with flattened ends passing through the perforations and
bent over into close union with the carbon, as and for the purpose set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twentieth day of January, in the year of our Lord
One thousand eight hundred and eighty two.
TIM DODT TT