Year: 1886

page_text: I ALEXANDER BERNSTEIN, of No 9ª Commercial Road, Pimlico, in the county
of Middlesex, Electrician do hereby declare the nature of this invention to be as
follows:-
My improvements relate to that type of incandescent electric lamps in which the
light-giving carbon is straight or slightly curved and the conducting wires are
sealed into the opposite ends of the glass bulb. In lamps of this kind there has
always been a certain difficulty on account of the strain produced by the expansion
and contraction of the different parts which strain caused the filaments to.
give out.
The glass bulb tends to expand outwards, the conducting wire inwards and the
carbón tends to lengthen itself as soon as the lamp becomes heated by the current.
These different actions are detrimental to the lamp unless their effect on the
carbon is counteracted by suitable means. I find that this can be done by the
interposition of a flexible conductor between two different parts of the rigid
conductor inside the lamp. For this purpose I make the conducting wires of
platinum where they pass through the glass and where they are attached to the
carbon. These two pieces of platinum are connected to each other by means of a
flexible strip of metal preferably copper which is bent on itself and placed at right
angles to the direction of the conducting wires. In this way I obtain the required
rigid fixing of the carbon and at the same time a sufficient flexibility to avoid the
hurtful effects of the expansion and contraction above named.
ווי מ
"
G. F. REDFERN,
Agent for the Applicant.

page_text: +
i
Improvements in Incandescent Electric Lamps.
1 ALEXANDER BERNSTEIN of N° 9ª Commercial Road, Pimlico, in the county of
Middlesex, Electrician, 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 improvements relate to that type of incandescent electric lamps in which
the light-giving carbon is straight or slightly curved and the conducting wires
are sealed into the opposite ends of the glass bulb. In lamps of this kind there
has always been a certain difficulty on account of the strain produced by the
expansion and contraction of the different parts which strain caused the carbon or
light giving body to give out.
The glass bulb tends to expand outwards, the conducting wires inwards and the
carbon or light-giving body tends to lengthen itself as soon as the lamp becomes
heated by the current. These different actions are detrimental to the lamp unless
their effect on the carbon or light-giving body is counteracted by suitable means.
I find that this can be done by the interposition of a flexible conductor between
two different parts of the rigid conductor inside the lamp. For this purpose
I make the conducting wires of platinum where they pass through the glass and
where they are attached to the carbon. These two pieces of platinum are
connected to each other by means of a flexible strip of metal, preferably copper,
which is bent on itself and placed at right angles to the direction of the conducting
wires. In this way I obtain the required rigid fixing of the carbon or light-giving
body and at the same time a sufficient flexibility to avoid the hurtful effects of the
expansion and contraction above named.
In order to enable my invention to be fully understood I will proceed to describe
the same by reference to the accompanying drawing in which figure 1 is a sectional
elevation and figure 2 a horizontal section of an incandescent electric lamp made
according to my invention. Similar letters in both figures represent similar parts.
at, is the light-giving body preferably made of carbon and held at each end in
suitable metal sockets a¹; b is the glass bulb; c, c, are two pieces of enamel which
are welded together with the glass and through which the platinum conducting or
leading-in wires d, d, are passed, the ends of these wires d, d, are connected to the
thin and flat copper strips e, e, bent into the form shewn. These copper strips e, e,
which are also connected to the sockets a', act as springs for the purpose explained
above. It will be obvious that other forms of flexible connection can be employed
instead of the one shewn in the drawing.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :
1. In incandescent electric lamps of low resistance connecting the ends of the
carbon or light-giving body with the conducting or leading-in wires by means of
conductors which are flexible in the direction of the carbon as and for the purpose
set forth.
2. The manufacture and use of the improved incandescent electric lamp herein-
before described and illustrated in the accompanying drawing.
G. F. REDFERN,
Agent for the Applicant.