Improvements relating to Electric Incandescence Lamps.
Year: 1889

page_text: Date of Application, 16th Apr., 1889
Complete Specification Left, 17th Feb., 1890-Accepted, 22nd Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements relating to Electric Incandescence Lamps.
I, ALBERT AUGUSTUS GOLDSTON, of Post Office Buildings, Middlesborough, in the
county of York, Electrical Engineer, do hereby declare the nature of this invention
to be as follows:
My invention relates to electric incandescence lamps for use in a series circuit and
especially to such lamps as are provided with carbons or light giving conductors in
the form of a circle or segment of a circle.
The object of my said invention is to provide such lamps with improved cut-outs
adapted to operate automatically when the carbons or light giving conductors become
destroyed..
According to my said invention each of the leading in wires has a contact piece
attached to it and between the two contact pieces is arranged a cone or wedge of
insulating material.
To the large end of the cone or wedge is attached a metal piece which is adapted
to complete the electric circuit through the contact pieces, and to the small end of
the latter is attached one end of a spring, the other end of which is connected to the
head of the lamp. This spring normally tends to draw the metal piece on the cone
or wedge into contact with the contact pieces but is prevented from doing so while
the carbon or light giving conductor is intact owing to the fact that the said carbon
or conductor is sufficiently strong to prevent the leading-in wires from expanding to
allow the cone or wedge, to be drawn towards the contacts. Should, however, the
carbon or light giving conductor be destroyed the cone or wedge and metal piece
are moved under the action of the spring and so make the desired contact.
In some cases I modify the- construction herein before described by bending the
lower ends of the leading in wires to a suitable angle and placing between them a
plate of insulating material the edges of which are inclined or wedge shaped. In
such cases however the metal piece adapted to complete the short circuit is arranged
upon the top
of the said plate.
As the additional weight of the cut-out device may tend to cause the carbon with
the leading in wires and other parts to fall over towards the bulb of the lamp when
the latter is placed upon its side, I preferably attach light stems to the leading in
wires which.stems will touch the bulb upon the carbon and other parts becoming very
much out of a perpendicular or normal position. Or these stems may be fitted to the
bottom of a guide stem which can be employed for guiding the cones and contact
piece.
I sometimes dispense with the use of a spring the cutting out device in this case
being operated by gravity and in such case, in order to enable the cut-out to operate
when the position of the lamp is reversed (turned upside down), I employ a double
cone or wedge of insulating material with the metal piece placed between their two
larger ends, the cones or wedges and the metal piece being, in this case, placed
between four contact pieces, two on each of the leading-in wires. With this con-
struction, should the metal piece between the cones be required to be larger (in
order to give the desired weight) than will pass between the two leading-in wires,
portions of the metal piece are cut away so that normally there is no short circuiting
between it and the leading-in wires.
In the above form a hole is also preferably made vertically through the centres of
the cones, wedges and metal piece which enables the cones to travel centrally upon a
suitable pin or guiding stem attached to the head of the lamp.
In preparing the carbons in light giving conductors for this lamp they may be

page_text: made by cutting sections from carefully prepared tubes of carbon, a portion of each
ring being afterwards cut away, or carbons may be moulded in the form of a ring and
after being dried may be suitably cut to the forms required.
Dated the 16th day of April 1889
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to Electric Incandescence Lamps.
I, ALBERT AUGUSTUS GOLDSTON, of Post Office Buildings, Middlesborough, in the
county of York, Electrical Engineer, 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:-
My invention relates to electric incandescence lamps for use in a series circuit and
especially to such lamps as are provided with carbons or light giving conductors in
the form of a circle or segment of a circle.
According to my said invention I provide such lamps with improved cut-outs
adapted to operate automatically when the carbons or light giving conductors become
destroyed, and for this purpose each of the leading-in wires has a contact piece
attached to or formed upon it; and in conjunction with these two contact pieces is
arranged a movable contact piece in such a manner that, when the circuit through the
light giving conductor is interrupted, by reason of the breakage of such conductor, the
said movable contact piece, either under the action of a spring or owing to gravity,
will make contact with the fixed contacts, and so complete the circuit through the
lamp and thus preserve the continuity of the series circuit. I also provide for
laterally supporting such cut-out mechanism, and for the manufacture of carbons for
use in the said lamps.
To enable my invention to be fully understood I will describe the same with
reference to the accompanying drawing, in which―
Figure 1 is an elevation of a lamp provided with a cut-out constructed according
to my invention, and
Figures 2, 3 and 4 are views illustrating modifications.
Figure 5 is a section on the line
supporting the cnt-out laterally.
figure 1 showing the arrangement for
Similar letters of reference indicate corresponding parts in the several figures.
a is the lamp globe or bulb, b is the head of the lamp, c, c are the leading in wires,
and d is the light giving conductor secured to the ends of the latter.
fixed contacts, and fis the movable contact.
e, e are the
As shown in figure 1 this contact f is affixed to the large end of a supporting
piece 9, of insulating material in the shape of a cone located between the fixed
contacts e, e, which latter are shaped as shown in figure 1* to prevent the cone from
slipping laterally from between them. To the small end of the cone g is attached
one end of a spring h, the other end of which is connected to the head of the lamp.
This spring normally tends to draw the contact piece f on the cone g into contact
with the contact pieces e, e but is prevented from doing so, while the carbon or light
giving conductor d is intact, owing to the fact that the said carbon or conductor is
sufficiently strong to prevent the leading in wires from expanding to allow the cone
to be moved by the spring h. Should, however, the carbon or light giving conductor
be destroyed the cone g and contact fare moved under the action of the said spring
and so complete the circuit through the cut-out. I sometimes make the contact
piece longer than shown and form holes therein through which the leading in wires
can pass without contact, the object of this arrangement being to hold the said
leading in wires in their proper position in case of the rupture of the carbon, thereby
preventing the shunt circuit being accidentally broken after the cut-out has acted.

page_text: Instead of making the supporting piece g in the shape of a cone it may have the
form of a wedge, in which case the contact pieces e, e are correspondingly shaped as
shown in figure 1.
In the modification shown in figure 2 the lower ends of the leading-in wires c, c are
bent to an angle, and the piece upon which the contact fis supported is a plate of
insulating material of the form shown in figure 2. This plate is placed between the
bent portions of the wires c, c and its edges are inclined or wedge-shaped, so that
when the carbon d breaks it will, under the action of the spring, force the said wires
apart thus allowing the contact to make contact with the contacts e, e.
In the modification shown in figure 3, which is substantially the same as that
shown in figure 2, the supporting piece g is dispensed with, the contact being
provided with openings f¹, f¹, as shown in figure 3ª, through which the leading-in
wires pass.
Insulating pieces or collars c¹, el are fixed upon the wires c, c to prevent the contact
piece from making contact therewith.
As shown in figure 4 the use of a spring is dispensed with, the cut-out device in
this case being operated by gravity. In order to enable the cut-out to operate when
the position of the lamp is reversed (turned upside down) 1 employ an insulating
supporting piece in the form of a double cone or wedge, the contact piece ƒ being
placed between them. I also employ two pairs of contact pieces e, e as shown; should
the contact be required to be larger (in order to give the desired weight) than will
pass between the two leading-in wires, portions of the said contact are cut away or holes
are formed therein, as shown at f³, f in figure 4, so that normally there shall be no
short circuiting between it and the leading-in wires.
In the above form the cones or wedges and contact piece fare arranged to slide
upon a pin or guiding stem i attached to the head of the lamp.
In all the above modifications the contacts e, e are represented as being attached to
the leading-in wires, but it is to be understood that such contacts may be formed out
of the leading-in wires themselves.
As the additional weight of the cut-out device may tend to cause the carbon with
the leading-in wires and other parts to fall over towards the bulb of the lamp when
the latter is placed upon its side, I preferably attach light stems or arms j, j to the
leading-in wires, as shown in figures 1 and 5, which stems will touch the bulb upon
the carbon and other parts becoming very much out of their normal position.
Steadying arms may, if desired, be fitted to the bottom of a guide stem such as i
figure 4, which can be employed for guiding the supporting pieces g and contact
pieces fin each of the modifications described.
In preparing the carbons in light giving conductors for this lamp they may be made
by cutting sections from specially prepared tubes of carbon, a portion of each ring
being afterwards cut away; or carbons may be moulded in the form of a ring, and
may be suitably cut to the forms required.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. In an electric incandescence lamp having a light emitting conductor of the kind
herein before described, the employment, in combination with contacts fixed to or formed
integral with the leading-in wires within the bulb, of an independent movable short
circuiting or contact piece attached to or formed integral with a piece for exerting a
wedge like action upon the leading-in wires, but incapable of movement so long as
the light emitting conductor is intact, but which piece when the conductor is ruptured
is free to move under the action of a spring or weight, substantially as, and for the
purpose, set forth.
2. In an electric incandescence lamp of the kind provided with cut-out mechanism,
the employment of steadying arms, substantially in the manner set forth.
3. The manufacture of light emitting conductors for electric incandescence lamps,
substantially as set forth, and the use of the same when so manufactured.

page_text: 4. In an incandescence lamp provided with cut-out mechanism of the kind
described, a guide stem upon which the movable contact piece slides, substantially as
set forth.
5. The manufacture and use of electric incandescence lamps having the improved
cut-out mechanism hereinbefore described and illustrated in figures 1, 2, 3 and 4 of
the accompanying drawing.
Dated the 17th day of Eshen 1800
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.