Improvements in or connected with Electric Arc Lamps.
Year: 1897

page_text: Improvements in or connected with Electric Arc Lamps.
I, FREDERIC STANHOPE WORSLEY, of 119, Church Lane, Charlton, in the County
of Kent, Electrical Engineer, do hereby declare the nature of my invention to be
as follows:-
-
My invention relates to electric are lamps in which the feeding of the carbons
is effected by a differential system of coils and particularly to lamps which are
used upon a circuit in series with other are lamps, or other translating devices; and
my said invention has for its object to provide a simple and efficient means for
short circuiting the arc of the lamp if, from any cause, the proper feeding of the
carbons be interrupted to a dangerous extent. For this purpose I utilize the
main coil of the lamp to effect and maintain the said short circuiting of the lamp
by causing the core of the said main coil to short circuit the current across the
carbons so that the lamp is cut out. The following is a convenient arrangement
according to my invention:-
I will presume in this description for the sake of brevity that the main coil is
at the positive terminal of the lamp but it will be readily understood that the
arrangement can also be applied to cases where the main coil is at the negative
terminal. I provide on the frame of the lamp and insulated from it, and beneath
the core of the main coil, a piece of iron which is electrically connected to a part
of the circuit after it leaves the main coil and before it reaches the carbons.
When the conditions are such that the shunt coil has acted to a predeterminal
limit at which the lamp is to be cut out, the core of the main coil comes into
contact with the aforesaid piece of iron and is magnetically held thereby and, as
this iron is connected to a part of the circuit before it reaches the carbons and the
said core is, through the frame and mechanism of the lamp, or otherwise, in
electric connection with the circuit in advance of the carbons, the carbons are
short circuited. The core of the main coil may normally be held out of contact
with the piece of iron by means of a spring or its equivalent.
ampoof commected with Blectric Arc Lamps.
1, FREDERIC STANHOPE WORSLEY, of 119, Church Lane, Charlton, in the County
of Kent, Electrical Engineer, do hereby declare the nature of this invention and
[Price 8d.]

page_text: 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. are lamps in which the feeding of the carbons
is effected by a differential system of coils, and particularly to lamps which are
used upon a circuit in series with other arc lamps, or other translating devices and
my said invention has for its object to provide a simple and efficient means for
short-circuiting the lamp if, from any cause, the proper feeding of the carbons be
interrupted to a dangerous extent. For this purpose I utilize the main coil of the
lamp to maintain the said short-circuiting of the lamp by causing the core of the
said main coil to effect the short-circuiting of the current across the carbons so
that the lamp is cut out. The following are convenient arrangements according
to my invention, which I will describe with reference to the accompanying draw-
ings which shew so much of two different forms of the lamp as is necessary to
explain my invention.
I will presume, in this description, for the sake of brevity, that the main coil is
at the positive terminal of the lamp; but it will be readily understood that the
arrangement can also be applied to cases where the main coil is at the negative
terminal.
e
In the arrangement shewn in Figure 1 I provide on the frame A of the lamp
and insulated from it and beneath the core b, of the main coil B, a piece or block C,
of iron or other magnetisable material (hereinafter referred to as the block C)
which is electrically connected to a part of the circuit after the current leaves the
main coil and before it reaches the carbons. The main coil B is electrically con-
nected to the carbons by its end being pinched between the binding screws
on a conducting piece E to which the lead to one of the carbons is connected. To
prevent the core b from coming into contact with the block C when the lamp is
not in operation I provide a spring y or its equivalent which at one end bears upon
the frame A and at the other end upon a projection on the core b. When the
conditions are such that the shunt coil I) has acted to a predetermined limit at
which the lamp is to be cut out, the core of the main coil has been thereby
caused to overcome the influence of the spring g and come into contact with the
aforesaid block C, and is magnetically held thereby and, as this block is electrically
connected to a part of the circuit after the current has gone through the main
coil B and before it reaches the carbons and as the said core is then, through the
frame, or mechanism of the lamp, or otherwise in any suitable way, in electric
connection with the circuit beyond the carbons, the lamp is short circuited, the
current then passing through the coil B, block C, core band thence through the
lamp frame A.
In the second arrangement as shown in Figure 2 the short circuiting of the lamp
is effected by providing the core with a conducting connection F and spring
contact piece f which makes contact with the top binding screw e at, or
immediately before, the time the core reaches the block C which, in this case,
is not necessarily insulated from the frame A and is not connected electrically
with the circuit except after the current has passed through the carbons, the short
circuiting of the lamp being effected by the current being caused to pass through
the said binding screws e, contact piece f, connection and core and out by
the frame of the lamp. When the lamp is not in operation the core 6 of the
main coil B is held out of contact with the block C, by the spring g, which acts
against the underside of the connection F.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. In electric arc lamps provided with short circuiting devices the utilization of
the main coil of the lamp to maintain the short circuiting of the lamp, by causing
the core of the said main coil, when the proper feeding of the carbons is inter-

page_text: rupted, to come in contact with, and be magnetically retained by, a piece or block
of iron or other magnetisable material and short circuit the carbons; substantially
as herein before described.
2. The arrangement and combination of parts constituting means for short
circuiting the carbons of an electric arc lamp when the proper feeding of the
carbons is interrupted, substantially as hereinbefore described and illustrated in
Figure 1 of the accompanying drawings.
3. The arrangement and combination of parts constituting means for short cir-
cuiting the carbons of an electric arc lamp when the proper feeding of the carbons
is interrupted substantially as hereinbefore described and illustrated in Figure 2
of the accompanying drawings.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.