IMPROVEMENTS IN ARC REGULATOR LAMPS
Year: 1882

page_text: LETTERS PATENT to Rookes Evelyn Bell Crompton of the Mansion House
Buildings Queen Victoria Street in the City of London Engineer, for an
Invention of "IMPROVEMENTS IN ARC REGULATOR LAMPS”
PROVISIONAL SPECIFICATION left by the said Rookes Evelyn Bell
Crompton at the Office of the Commissioners of Patents on the 14th July
1882.
ROOKES EVELYN BELL CROMPTON of the Mansion House Buildings Queen
Victoria Street in the City of London Engineer IMPROVEMENTS IN ARO
REGULATOR LAMPS
My invention relates more particularly to the improvement in Electric Lamps
described in my Provisional Specification filed with my application for Patent
N° 346. on the 24th of January of the current year and is applicable in cases
where the upper and lower carbon carriers are connected together by cords chains
or other suitable flexible connection passing over pulleys so arranged that the
travel of each carbon is controlled by the other. For convenience I hereafter call
this flexible connection the connecting cord.
In one arrangement I cause one portion of this connecting cord to gear with
a sheave or pulley mounted on the same axis as the first wheel in the train of the
gearing frame described in the above mentioned Provisional Specification; this
gearing frame is connected to an electro magnet or solenoid in such manner that
it rises and falls according to the degree of magnetisation of the armature or of
the core of the solenoid. By this rising and falling it advances or retires the
carbons affixed to the connecting cord and regulates the length of the arc.
I can also utilize a motion of the gearing frame so produced as a means of
actuating a feed mechanism by placing a fixed stop or finger which lifts the break
off its wheel when the gearing frame has moved to the position which it occupies
when the carbons need to advance and the lamp feed. In such case the gearing
frame is suspended on a bight of the connecting cord and the pulleys over which

page_text: the latter passes are so chosen that in the advance of the carbons due to their
consumption the gearing frame maintains its place.
I can apply the same arrangement of gearing the sheave or pulley of the
gearing frame to a cord which is employed as the suspending cord of one carbon
only, in such cases where it is proposed that the lamp mechanism should work by
the advancing motion of one carbon only.
Further I can employ this same contrivance with any of the other arrangements
of lamp mechanism referred to in my Provisional Specification filed with my
application for Patent N° 346 on the 24th of January of the present year.
When the motion of the core of the solenoid regulates the feed in the manner
above described I usually render the action of the solenoid more delicate and
reliable by making the core of an electro magnet with fine wire coil and placing
such coil on a derived circuit or wind the solenoid differentially. or employ two
solenoids acting on opposite ends of the core the one being on the main and the
other on a derived circuit.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Rookes Evelyn Bell Crompton in the Great Soal Patent Office
on the 13th January 1883.
ROOKES EVELYN BELL CROMPTON of the Mansion House Buildings Queen
Victoria Street in the City of London Engineer "IMPROVEMENTS IN ARO
REGULATOR LAMPS'
"
My Invention relates more particularly to the improvement in electric lamps
described in the Specification filed in pursuance of Letters Patent granted to me
bearing date the 24th day of January 1882 N° 346 and is applicable in cases where
the upper and lower carbon carriers are connected together by cords chains or
other suitable flexible connections. passing over pulleys so arranged that the travel
of each carbon is controlled by the other.-For convenience I. hereafter call this
flexible connection the connecting cord.
In one arrangement I cause.one portion of this connecting cord to gear with
a sheave or pulley mounted on the same axis as the first wheel in the train of the
gearing frame described in the before mentioned Specification; this gearing frame
is connected to or influenced by an electro-magnet or solenoid in such manner
that it rises and falls according to the degree of magnetization of the armature
or of the core of the solenoid. By this rising and falling it advances or retires
the carbons affixed to the connecting cord and regulates the length of the arc.
I can also utilize a motion of the gearing frame so produced as a means of
actuating a feed mechanism by placing a fixed stop or finger which lifts the break
off its wheel when the gearing frame has moved to the position which it occupies.
when the carbons need to advance and the lamp feed. In such case the gearing
frame is suspended on a bight of the connecting cord and the pulleys over which
the latter passes are preferably so chosen that in the advance of the carbons due
to their consumption the gearing frame maintains its place. A similar device can
be employed when the movement of the carbons is regulated by other means so
that when the advance of the two is in a certain proportion the gearing frame
which regulates the feed mechanism is stationary.
I can apply the same arrangement of gearing the sheave or pulley of the gearing
frame to a cord which is employed as the suspending cord of one carbon only, in
such cases where it is proposed that the lamp mechanism should work by the
advancing motion of one carbon only. Further I can employ this same contrivance.
with any of the other arrangements of lamp mechanism referred to in the Specifi-
cation filed in pursuance of Letters Patent Ñ° 346 granted to me dated the 24th of:
January 1882.
When the motion of the core of the solenoid, regulates the feed in the manner
above described I usually render the action of the solenoid more delicate and
reliable by winding the core of the electro magnet with fine wire coil and placing
such coil on a derived circuit, or I wind the solenoid differentially or employ two
solenoids acting on opposite ends of the core, the one circuit or solenoid being in
the main and the other in a derived circuit.
But that the nature of the invention may be the better understood I will proceed.
by the aid of the accompanying Drawings to describe the same more in detail.
DESCRIPTION OF THE DRAWINGS
Figures 1 and 2 shew front and side views of this arrangement Figure 3 gives a
separate view of the gearing frame as seen from above.
The framing of the lamp consists of the two side rods B. B¹. which are strong.
metal tubes passing through the top, middle and bottom frame plates respectively

page_text: marked A A' A² and firmly secured to them by suitable screws, pins or other means
adapted to the purpose. The middle frame plate A¹ consists of a strong casting
into which is rivetted a copper or brass pan shaped shield C which serves 1** to
support the lower ends of the guide rods E. E'. 2nd to hold the insulating porcelain
washer C, 3rd to prevent the fumes from the arc from rising into the body of the
lamp.
The upper carbon c is carried by a holder c' sliding freely between the guide
rods E. E The lower carbon d, is carried in a holder d¹. which is free to rise and
fall in the guide tube D...
The two carbon holders are connected together by a cord band or chain i. i. i.
terminating at I passing into the guide tube at J thence passing successively round
the pulleys h. h¹: h³. h h h thence down to the carbon holder c¹. to which it is
connected by a link of silk cord or other suitable insulating material.
The upper carbon holder c'. is insulated from the body of the lamp. Connection
is made to it from the terminal by an insulated flexible conductor r. The lower end
of the carbon holder d'. is similarly connected to the body of the lamp by the spiral
flexible conductor r.
The connecting cord i. is of suitable length to allow of the two carbon holders
being drawn back to the full extent of their stroke.
The separation of the carbons for the object of forming the arc is effected by the
pulley h. which is mounted in a vibrating gearing frame e. This pulley h*. has its
periphery covered with rubber or other suitable substance adapted to prevent the
connecting cord slipping on it and to cause such cord to gear with it.
The gearing frame carries a train of 8 toothed wheels ƒfƒ³. The first wheel f
is a brake wheel and is controlled by the brake g in a similar manner to the
arrangement described in the Specification of Letters Patent granted to me bearing
date January 24 1882. The last wheel f. is mounted fast on the same axle as the
pulley h. and revolves with it.
The gearing frame e. is mounted on a double or forked lever k. k. bent so as to
pass round the carbon holders and guide rods. This lever k. k. is pivotted at K and
supported by being connected to the side rod B¹.
"
The soft iron core m is attached to the gearing frame e by the link p.
The solenoid M. N has its lower half M wound with thick wire coupled in series
with the parts connected with the carbons. The upper half N is wound with a
large number of turns of fine wire and forms a shunt of high resistance to the arc
and is coupled parallel to it.
•
The upper carbon is guided at its lower end as near as possible to the arc by the
porcelain washer C¹ the lower carbon d. being correspondingly guided by a similar
washer D¹.
A removeable hinged cover o. o. to protect the working parts, a conical reflector P
for out of door use and a globe or glass: Q for protecting the are are shewn in
Figures 6 and 7. This globe or glass Q can be slid down on the lower guide
tube D when desired so as to give access to the carbons within.
The action of the lamp is as follows.-
The current on first entering the lamp by way of the main coil M. draws down
the core m and with it the gearing frame e thus separating the carbons c and d
and forming the arc.
As the resistance of the arc increases from the consumption of carbon the current
in the shunt coil N increases and tends to raise the core m and gearing frame e.
until the free end of the brake lever g. comes in contact with the fixed stop G, and
in so doing releases the wheel f. the carbons c and d. being therefore set free to
approach one another and thus make a feed movement which continues until the
balance between the pull of the two solenoids on the core m being restored the
gearing frame e: rests in its normal position.
.
This arrangement provides 1t very steady and equable feed movements 2nd a
good focus keeping arrangement 3rd facility for the use of carbons of great length
without unduly lengthening the lamp. 4th means for ensuring the effective guidance

page_text: of the carbon rods at points very close to the arc ends thereof 5th the prevention
of the fumes from the arc or combustion of the carbons entering the lamp.
Figure 4 shews another modification of the parts. In this arrangement the two.
solenoids are side by side and the main coil M draws its core m. downwards whilst
the shunt coil draws its core upwards in other respects the arrangements are
similar to those shewn in Figures 1 and 2.
Figure 5 shews a modification of a portion of the apparatus in which the
vibrating gearing frame e. is operated by electro magnets instead of by solenoids
the keeper m². passes across the face of the magnets M which magnets are wound
O differentially i.e. the thick coils coupled in series with the arc and the fine wire
coils coupled as a shunt to the arc as above described.
I can in certain cases if found desirable dispense with the main coil M so
controlling the gearing frame by a spring or otherwise that it naturally rests in its
lowest position, thus keeping the carbons a short distance apart, the high resistance
5 shunt coil being coupled parallel to the arc as before As soon as a current is sent
through the lamp it can pass at first only by way of the shunt which therefore is
powerfully affected and the core is drawn up. This allows the carbons to come
together and establish the current by way of the carbons, this somewhat reduces
the current in the shunt which therefore allows the carbons to spring apart
sufficient to form the arc, after this the feed movement continues as in the
arrangement first described.
This plan however can only be adopted when the current is provided by a
-battery or a magneto electric machine or by a machine separately excited or by a
machine with magnets on the shunt circuit.
I am enabled to meet this difficulty by the use of the arrangement described at
length in the Specification of my said former Letters Patent N° 346 1882, the
thick wire coils M being only in circuit so long as the-current is not passing by
way of the carbons, as soon however as the current commences to pass and the arc
is formed these thick wire coils M are automatically cut out of the circuit by the
cut out or relay therein described.
The before described arrangements of lamp mechanism may be placed below the
are instead of above it as may be found more convenient for such purposes as
light house illumination, naval or other uses-The changes in the mechanism which ⚫
will be necessary to effect this will be so obvious to any person practically
acquainted with such apparatus that further description is not necessary. And in
the case of the apparatus being thus modified so as to enable it to be used for a
non-focussing lamp (that is to say when motion is given to the upper carbon
only) that the pulley h. should be exchanged for a drum on which a sufficient
length of cord can be coiled to allow of the required travel of the upper carbon,
this drum being geared to the train of wheels and controlled by them as herein
before described, the cord will pass direct from this drum over the pulley h³. to the
carbon holder c¹. as before described. The lower frame A2, and tube D will be
exchanged for a simple cross head to hold the lower ends of the tubes B. B'. and
arranged so as to form a suitable support or holder for the fixed lower.carbon or
some other equivalent mechanical arrangement must be used.
Having thus described the nature of my said Invention and the means I adopt
in carrying the same into practical operation I would have it understood that what
I claim is
First. The vibrating gearing frame with one of its wheels gearing with the
connecting cord connecting the two carbon holders, together with the electro-
magnetic arrangements for controlling the same and causing the feed mechanism to
operate when necessary substantially as herein described.
Second The modification of the above suitable for the case in which one carbon
is fixed or when they both move but so as not to keep the arc in one place
substantially as herein described.
Third. The combination of parts forming the electric lamps herein described
viz. the guided carbon holder B which renders rack or clutch rod unnecessary the
.

page_text: pan shaped middle frame C'the focussing and feed arrangements all substantially.
as described and for the purposes set forth herein.
:
In-witness whereof I the said Rookes Evelyn Bell Crompton have hereunto
set my hand and seal this thirteenth day of January One thousand eight .
hundred and eighty three.
Witness
ALFRED & BROOKES.
59 Chancery Lane
London
ROOKES EVELYN BELL CROMPTON (L.S.)
ུ ,