Improvements in Electric Arc Lamps.
Year: 1891

page_text: Date of Application, 7th Mar., 1891
Complete Specification Left, 12th May, 1891-Accepted, 13th June, 1891
PROVISIONAL SPECIFICATION.
Improvements in Electric Arc Lamps.
I, WILLIAM HOPKIN AKESTER, of No. 15, Munster Road, Fulham, in the
County of Middlesex, Electrician, do hereby declare the nature of this invention
to be as follows :—
This invention relates to improvements in the construction of electric arc lamps
whereby the striking of the arc, the maintaining of the carbons at the required
distance from each other and the feeding of the same, are effected in a more regular
and reliable manner than is the case with similar lamps as ordinarily constructed,
whilst, at the same time, the mechanism for effecting those objects is greatly
simplified and less liable to get out of order.
The runners which carry the carbon holders are constructed in the ordinary
manner, that carrying the positive or upper carbon being heavier than the other.
The said runners are arranged in the usual manner to slide up and down on the two
vertical side rods of the lamp. A chain which passes over a sprocket or other
similar wheel or pulley at the upper part of the lamp, has its ends respectively
connected to the two runners. At the upper part of the lamp. in close proximity
to the before mentioned wheel or pulley, is arranged a solenoid provided with a
moveable soft iron core in connection with the lower end of which is an eccentric
block mounted on an arm which is loose on the wheel spindle, so that on the
upward movement of the said core, the eccentric block will be turned on its centre
and brought into contact with the periphery of the wheel or pulley and will partially
revolve the same in a direction contrary to that in which it is revolved, when free,
by the weight of the runner carrying the positive carbon holder. The said arm is
retained at any predetermined normal position by means of a spring or weight and
a suitable stop.
The current is passed by means of suitable connections from a terminal to and
through the positive and negative carbons through the frame and the coil of the
solenoid and out.
When the current is first admitted to the lamp, the soft iron core is drawn into
the solenoid, and, by its movement, brings the eccentric block into contact with the
periphery of the wheel or pulley and revolves the same to such an extent that the
points of the carbons are sufficiently separated to produce an arc of the desired
length. As the intensity of the current in the solenoid is reduced, the core
gradually regains its former position, and the eccentric block is moved out of
contact with the wheel or pulley which is left fee to be revolved, by the weight of
the runner carrying the positive carbon holder, in the opposite direction to that
hereinbefore referred to, thus effecting the requisite feeding of the carbons.
If, during the process of burning, the carbons are fed too quickly, the current
through the solenoid is intensified, and the soft iron core is again drawn into the
same, and the eccentric block is thereby brought into contact with the wheel, as
above stated.
Dated this 7th day of March 1891.
VAUGHAN & SON,
Agents for the Applicant.

page_text: Improvements in Electric Arc Lamps.
I, WILLIAM HOPKIN AKESTER, of 15, Munster Road, Fulham, in the County
of Middlesex, Electrician, do hereby declare the nature of the said invention and
in what manuer the same is to be performed to be particularly described and
ascertained in and by the following statement:-
This invention relates to an improved arrangement of arc lamp, whereby the
lamp is simplified and rendered more compact, handy, and less weighty, and also
less costly than are lamps as ordinarily constructed. The invention also has special
reference to improved means of automatically ensuring the necessary regulation of
the carbon conductors, whereby the separating of the carbons to form the arc, the
maintaining of the arc of the required length, and the feeding of the carbons
according to their relative consumption are effected in a more efficient and reliable
manner than is the case in arc lamps as ordinarily constructed, the mechanism for
effecting such regulating operations being materially simplified and rendered less
liable to get out of order.
On the accompanying drawings,
Fig. 1 represents a sectional elevation of an arc lamp constructed in accordance
with the present improvements, and
Fig. 2, represents an elevation, partly in section, at right angles to the plane
upon which Fig. is taken.
3, represents the holder or frame to which the glass globe (not shown) is
attached, and from which depend the usual side rods 4, fitted with a connecting
cross piece 5, secured by nuts 6, or the like, at a distance below the holder 3,
determined by the required fall of the upper or positive carbon holder 7.
The runner 8, carrying such carbon holder 7, is arranged in an ordinary manner
to slide up and down the rods 4, its traverse being limited by the frame 3, and
crosspiece 5. It is weighted with a series of lead discs 9, secured thereto and
between top and bottom plates 10, by screws pins 11, or with or by other suitable
means of rendering it sufficiently heavier than the negative carbon holder 12, (to
which it is connected as hereinafter described) to ensure the approach and feeding
of the carbons by gravitation.
The runner 13, which carries the negative carbon-holder 12, is secured by nuts 14
or the like, to a rod 15, which slides with metallic contact in and is guided in its
vertical movements by the frame 3, and crosspiece 5; each of which, at that part
through which the rod 15, passes, is cut away and fitted with a crossing tongue
piece 16, to prevent accumulation of any matter likely to cause undue friction
between the rod and the said fiame and crosspiece.
The traverse of the holder 12, is limited by stops 17, 18, fast on the rod 15, and
which respectively engage with the top side of the frame 3, and the underside of
the crosspiece 5, or by the stop 17, engaging in the downward movement of the rod
with the top side of the frame 3, and in the upward movement of the rod, with a
lateral extension 19, projecting from a top guide rod 20, rising from the frame 3,
the extension 19, being screwed or otherwise suitably secured to the top plate 21,
of a solenoid 22, which latter is supported by a suitable bracket 23, secured to the
top side of the frame 3.
Both of such runners (8, 13,) are connected by a chain or other suitable flexible
connection 24, one end of which is connected to the top end of the rod 15,
carrying the negative carbon holder, the other end being connected to the top
end of a rod 25, rising from the positive carbon holder, the latter rod extending
through the solenoid 22, and also through a hollow soft iron core 26, working in
connection therewith as hereinafter described. The chain or other flexible con-
nection 24, is supported by a sprocket, grooved, frictional or other suitable wheel

page_text: or pulley 27, which is free to rotate on a pin 28, carried by a bracket 29, supported
by and rising from the top plate 21, of the solenoid.
The core 26, of the solenoid is, as aforesaid, made hollow to permit of the passage
of the rod 25, and of the flexible connection 24. It has a limited movement
within the solenoid (depending upon the required length of arc, and effected in a
usual manner by the magnetism developed in the solenoid by the current feeding
the lamp) the limitation of its movement being effected by studs 30, projecting
therefrom and engaging with guiding slots 31, made in the frame 23, one of such
studs 30, being also connected to the casing 32, of a pneumatic cushion the inner
pheripherally grooved part 33, of which is supported by the frame 3.
On the pin 28, is also loosely mounted, a lever-arm 34, which, in its normal
inoperative position, is caused, by a spring 35, to rest on a stop 36, rising from the
plate 21; the arm 34, carries a stud 37, on which is loosely mounted a snail or cam
piece 38, formed with a bifurcated extension 39.
From the upper end of the core projects an extension 40, carrying a pin 41,
which engages with the extension 39, projecting from the snail or cam piece 38, and
is operative in actuating the latter in the manner and with the effect hereinafter
described.
The current enters the lamp at the terminal 42, (which is supported by but is
insulated from the frame 3,) and passes to the inside coil of the solenoid 22, and
from the outside coil thereof by an insulated flexible connection 43, passing through
an opening 44, in the frame 3, to the positive carbon (the holder of which is
insulated, as at 45, from its runner 8), thence through the negative carbon and the
metallic connections and framing 13, 15, 5, 4 and 3. to the terminal 46, where it
emerges.
The
When the current first passes to the lamp, the core 26, is more or less drawn
within the solenoid by the magnetism developed in the latter by the current
supplying the lamp, and as the core rises, its extension 40, causes the snail or
cam-piece 38, to be gradually turned about its pivottal connection 37, to the lever
arm 34, until the snail is caused to nip the flexible connection 24, connecting the
cai bon holders between itself and the adjacent periphery of the wheel 27.
continued rising of the core thereupon causes the wheel 27, to be gradually rotated
about its centre pin 28, in a direction contrary to that in which, when free, it is
rotated by the gravitating effect of the runner carrying the positive carbon holder,
and so causes the meeting ends of the carbons to be sufficiently separated to form
an arc of the required length, as the current through the solenoid decreases as the
resistance due to the increasing length of are increases the core, by gravitation,
gradually regains its zero position, (any sudden or irregular movement of the core
being prevented by the said attached pneumatic cushion), during which, it con-
sequently allows of the spring 35, returning the lever-arm 34, to its normally
supported position, and then frees the snail or cam-piece 38, from the wheel 27,
which is thereupon left free to be rotated, by the aforesaid surplus weight of the
runner carrying the positive carbon holder, in such a direction as to ensure the
requisite feeding of the carbons. If the carbons should be fed too quickly the con-
sequently increased current through the solenoid causes the core to be again drawn
more or less thereinto with the effect herein before described.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1The improved arc lamp, consisting of the supporting frame 3, the runners
carrying the carbon conductors connected and supported as described, the supported
and supporting solenoid with its contained hollow core, and the means described
(consisting of the parts 24, 27, 34, 38, 40, and their respective attachments) for
automatically operating and regulating the carbon conductors, combined and
arranged in the improved manner hereinbefore described with reference to the
accompanying drawings.

page_text: 2: The application to arc lamps, of the means hereinbefore described, consisting
of the parts 24, 27, 34, 38, 40, and their respective attachments, for automatically
operating and regulating the carbon conductors of such lamps.
Dated the 14th day of April 1891.
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C., Agents for the Applicant.