Improvements in Electric Arc Lamps.
Year: 1890

page_text: Date of Application, 17th Mar., 1890
Complete Specification Left, 29th July, 1890-Accepted, 30th Aug., 1890
PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lamps.
I, JAMES CAMPBELL of 5 Tillie Street Glasgow, in the County of Lanark,
Scotland Electrical Engineer, do hereby declare the nature of this invention to be
as follows:-
My invention relates to Double or Multiple-carbon Electric Arc Lamps, and consists
in the arrangement, combination and construction of parts.
A double carbon are lamp as constructed according to my invention comprises, an
electro magnet in the main circuit which upon the current passing it attracts an
armature on one end of what may be terined the striking lover, to the other end of
which levor is attached springs connected respectively to one end of the lever grips
to which same end of grips are attached connecting rods connected at other ends to
what may be termed the feed lever provided with an armature actuated by a high
resistance coil which is in shunt to the lamp circuit. The lever grips before referred
to consist each of an ordinarily flanged socket, on one side of which is fulcrumed the
grip consisting of an angled lever, one arm of which acts on the carbon rod, which,
when the compression caused by the shunt coil is on, releases said grip and allows the
carbon rod to feed down. The springs before referred to each suspend a carbon rod
and keep the are always formed, and thus prevents the upper carbon from falling on
lower while current is flowing.
D. F. MASON,
Patent Agent.
COMPLETE SPECIFICATION.
Improvements in Electric Arc Lamps.
I, JAMES CAMPBELL of No. 5 Tillie Street Glasgow, in the County of Lanark,
Scotland, 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 ascer-
tained in and by the following statement :-
My said invention relates to Double Carbon Lamps, and consists in the improved
arrangement and construction of parts set forth; whereby the sure action of the lamp
is attained, the arc made constant and simple in striking, no extra power being
absorbed in lifting the carbon to strike the arc, it being done by the current passing
through the lamp, which may be run any number in series and from either shunt or
series wound dynamos, and in circuit with nearly every make of arc lamp in present
use.
And in order that my invention may be properly understood I have appended an
explanatory sheet of drawings whereon Fig. is a sectional elevation of the main
plate with working parts of lamp thereon. The section is taken partly through the
standard Fig. 3 Fig. 3 is a plan thereof. Fig. 2 is a sectional elevation at right
angles to Fig. 1, and showing an ordinary bottom carbon holder which is fixed to und
depends from plate n by rod z; which is shown detached as it does not constit::te
part of invention, being only for explanation.
The lamp as constructed according to my said invention comprises on the round
plate n an ordinary electro magnet m in the main circuit, which upon the electric
current passing it attracts an ordinary armature o on one end of what I term the
striking lever p, which is formed as shown more clearly in plan Fig. 3, and which is
pivoted to and between the two hollow standards r. r fixed rigidly on plate n. To
the other projecting ends p' of lever p. are connected by adjusting screws t³ shown at
[Price Gal

page_text: Fig. 1, springs t. t whose other ends are hooked to the lever grips u consisting of a
small angled lever or bell crank pivoted as shown at Fig. 1 in a socket ², a piece of
side of said socket being slotted or cut out as shown at u Fig. 2, to admit grip.
The sockets ut slide over the upper carbon rods or holders v. v unless when held
thereto by the grips u acted on by springs. The grips u at point where springs t t
are hooked to, have also connected thereto (for the purpose of releasing the grips)
rods w, the upper ends of which rods are fixed to projecting arms a' of what I term
the feed lever a, of somewhat similar form to lever p but reversed in direction as
more clearly shown at Fig. 3, and which said lever a is also pivoted between
the standards r. by the pins s.s; the other end of lever a being provided with an
ordinary armature c actuated by an ordinary high resistance coil or electro-magnet b
which is in shunt to the lamp circuit.
The other necessary parts of lamp such as the case, terminals, &c. &c., being
common to all such lamps are not shown, as being well known to electricians.
The lamp operates as follows. The main current passes first through the magnet m
to the upper carbons and returns by the lower carbons, as well known to electricians.
When the are has become long enough to send part of the current through the shunt
coil the armature c on feeding lever a is attracted, and by this movement sufficient
pressure is brought to bear by means of the strut rod w, on the grip u, to release
said grip and allow the upper carbon rod with carbon in bottom thereof to feed as
required to compensate for the burning away of the carbon. When the carbons
approach each other at feeding, the current being diverted from coil b the lever a is
raised by and allows springs tt' respectively to press the grips against, and hold
suspended, the carbon rods v. ' in sockets . The current now passing throngh
magnet mattracts armature-o and lifts lever end pl and also thereby springs t t and
carbon rods v v², and thus strikes the arc. The upper carbon is thus suspended and
prevented from falling on lower carbon while the current is flowing. The are may
be lengthened or shortened by means of the adjusting screws
spring t, t.
on top of each
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the sume is to be performed I declare that what I
claim is.
1st. The arrangement and construction of mechanism (except the magnets m, b,
and armatures o, e) for operating the upper carbons of double carbon are lamps, as
hereinbefore described and shown on drawings.
2nd. The arrangement or combination of grips u, springs t, t¹, rods w, and levers a p.
whereby the releasing, locking and lifting of upper carbon rods », v¹, is effected, as
described and shown.
3rd. The particular combination and construction in the particular manner, of the
grip u and socket u', as and for the purpose described and shown.
Dated this 26th day of July 1890.
DAVID F. MASON,
Glasgow, Patent Agent.