An Improvement in Electric Arc Lamps.
Year: 1897

page_text: An Improvement in Electric Arc Lamps.
I, JAMES BROCKIE, of No. 12, Tyson Road, Forest Hill, in the County of Kent,
Engineer, do hereby declare the nature of this invention to be as follows:
My invention relates to the construction of the regulating and feeding apparatus
of an electric arc lamp in such a manner that a single solenoid having its coil in
the lamp circuit determines the position of the carbon and its feed when required.
For this purpose, I provide the upper carbon or a rod to which the carbon is
attached with notches at intervals, such for instance an inch apart, and I enclose
the carbon or rod in the tubular iron core of a solenoid having its coil in the
lamp circuit. On the core I pivot a pawl in such a position as to engage in any
notch of the carbon or rod. When the carbons are in contact, the lamp being
put in circuit, the solenoid attracts its core upwards raising the carbon and striking
the arc.
As the carbons become consumed the increasing resistance of the arc
weakens the solenoid so that the core and carbon gradually descend maintaining
the arc approximately constant. When the carbon has thus descended a certain
distance the pawl meeting a stop becomes disengaged and the carbon descends
towards the lower carbon whereupon the solenoid raises its core with the pawl
which engages in the next higher notch, and the action is then repeated. The
carbon or its rod may be attached to a plunger working more or less tightly within
the core so as to damp the movement of the carbon.
Instead of enclosing the carbon or its rod within a tubular core, it may be
guided at the side of a core which has the pawl pivotted on it or on a lever con-
nected to it.
Cantambor 1807
ABEL & IMRAY,
Agents for the Applicant.
An Improvement in Electric Arc Lamps.
I, JAMES BROCKIE, of No. 12, Tyson Road, Forest Hill, in the County of Kent,
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 the construction of the regulating and feeding apparatus
of an electric arc lamp in such a manner that a single solenoid having its coil
in the lamp circuit determines the position of the carbon and its feed when required,

page_text: which I will describe referring to the accompanying drawing which is a vertical
section of a lamp according to my invention.
In the rod B, to which the upper carbon C is attached is provided a series of
notches B, at intervals of, say, an inch apart, and the said rod is enclosed in the
tubular iron core A¹ of a solenoid A which is in the lamp circuit. Upon a bracket
projecting from the core A¹ is pivotted a pawl D adapted to engage in the notches B¹
of the rod B. When the carbons are in contact, and the lamp is
put in circuit, the solenoid attracts. the
core upwards, raising the car-
bon C and striking the arc. As the carbons become consumed the increasing
resistance of the arc weakens the solenoid, so that the core A¹ with the rod B and
carbon C gradually descends and maintains the arc approximately constant until
the arm D¹ of the pawl D comes in contact with a pin E fixed to any part of the
frame F, and then the pawl is disengaged from the notch of the rod B which
descends so as to bring the carbons together whereupon the solenoid again raises
its core striking the arc and the pawl again engages in the next higher notch so
that the action is repeated.
The core A is provided with any ordinary dashpot arrangement such as that
shewn at A and a similar device is provided at B³, between the said rod and the
core A¹.
Instead of enclosing the rod B within the core A¹, the said rod may work in
guides at the side of a core which has the pawl pivotted on it, or on a lever con-
nected to it. It will be seen that according to this invention the regulation of
the arc is determined by the direct action of the solenoid core.
In cases where the arc is enclosed the carbons consume so slowly that the
momentary flicker which takes place when the withdrawal of the pawl lets the
carbons meet is not objectionable as it only takes place once in several hours.
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:-
An electric arc lamp wherein the arc is regulated by the direct action of the
solenoid, substantially as described with reference to the drawing.
Dated this 7th day of June 1898