An Arc Electric Lamp.
Year: 1890

page_text: Date of Application, 29th Sept., 1890
Complete Specification Left, 3rd Feb., 1891-Accepted, 7th Mar., 1891
PROVISIONAL SPECIFICATION.
An Arc Electric Lamp.
I, THOMAS BARNET GRANT, of No. 5, Selborne Road, Wood Green, in the
County of Middlesex, Electrician, do hereby declare the nature of this invention
to be as follows:
:-
My invention relates to an arc electric lamp with automatic regulator which is
constructed as follows. The upper carbon is attached to a tube or holder which
has on it freely fitting it a short iron tube and above that, more closely fitting it, a
second short iron tube. These two iron tubes are kept apart by a short stud and
a spring so adjusted that the upper tube is held in such a position that the carbon
holder can slide freely through it. Both the iron tubes are free to slide up and
down within a non-magnetic tube on which there is wound a solenoid coil in the
lamp circuit. The two carbons being in contact when the lamp is put in circuit,
the solenoid coil is strongly excited and attracts the two short iron tubes upwards,
while these two tubes at the same time attract each other. Owing to this attraction
the upper tube resting on the lower by the stud at one side becomes so far canted
that it acts as a clamp of the carbon holder, which is consequently raised by the
action of the solenoid until the lower iron tube meets a stop adjusted to the desired
length of arc, which is thus struck. Afterwards, owing to the resistance of the arc,
the solenoid becomes weaker and the carbon holder becomes unclamped and can
slip down feeding the carbon as it becomes consumed. In order to damp the action
of the regulating parts, the tube which holds the carbon may be charged with oil or
other liquid and have within it a stationary piston nearly fitting the tube, the liquid
thus acting as a cataract brake.
Dated this 29th day of September 1890.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Arc Electric Lamp.
I, THOMAS BARNET GRANT, of No. 5, Selborne Road, Wood Green, 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 invention relates to an arc electric lamp with automatic regulator which is
constructed as I shall describe referring to the accompanying drawings. Fig. 1 is a
side elevation partly in section of the upper part of the lamp. The upper carbon A
is attached to a tube or holder B which has on it, freely fitting it, an iron tube C
and above that, more closely fitting it, a second iron tube D. These two iron tubes
are kept apart by a short stud E at one side, but the upper tube D can stand in
such a position that the carbon holder B can slide freely through it. Both the
iron tubes C and D are free to slide up and down within a non-magnetic tube F on
which there is wound a solenoid coil G in the lamp circuit. The two carbons being
in contact, when the lamp is put in circuit, the solenoid coil G is strongly excited
and attracts the iron tube C upwards, while the two tubes C and D at the same
time attract each other. Owing to this attraction the upper tube D, resting on the
lower C by the stud E at one side, becomes so far canted that it acts as a clamp of
the carbon holder B, which is consequently raised by the attraction of the solenoid G
until ears H projecting from C meet the base or stops adjusted to the desired length
which is thus struck. Afterwards owing to the increased resistance of the
of
arc,
1 Price Bit 1

page_text: arc, due to the consumption of carbon, the solenoid G becomes weaker and the
tube D, being attracted to the tube C with less force allows the carbon holder B to
slip down, feeding the carbon as it becomes consumed. As shown in Figs. 2 and 3,
instead of the tube D, two rings K K' connected by two or more columns L may
be used as a clamp. And instead of making the lower ring K with stud E it may
be sloped off as shown in Fig. 3. In order to prevent the too rapid descent of the
tube B when released by the clamp D, it may be charged with oil or other liquid
and have within. it a stationary piston nearly fitting the tube, the liquid. thus
acting as a cataract brake, but to such a brake I make no claim.
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 :-
In an arc electric lamp, in combination with a solenoid coil in the lamp circuit
a tubular iron core and above it an iron tube resting on the core at one side, so
arranged that when the solenoid is excited the carbon holder is clamped by the tube
and moves with the core substantially as described.
Dated this 3rd day of February 1891.
ABEL & IMRAY,
Agents for the Applicant.