Arc Lamps
Year: 1886

page_text: Date of Application, 27th Oct., 1886.
Complete Left, 25th July, 1887.
Complete Accepted, 9th Sept., 1887.
Arc Lamps.
WALTER ROWBOTHAM and FREDERIC STANHOPE WORSLEY both Electrical Engineers
of 39 Lever Street Manchester do hereby declare the nature of this invention to be
as follows:-
In this invention we employ two solenoid coils fixed one on each side of the body
of the lamp, the first wound with thick wire, connected in the main circuit of the
lamp, and known hereinafter as the series solenoid, and the second of fine wire,
connected in a by-pass to the lamp circuit, and known hereinafter as the shunt
solenoid. In the Series solenoid we fit a brass tube, with a determined freedom of
movement, enclosing a fixed iron core; more particularly referred to hereinafter.
At the top of the said core we attach a chain, which passing over a grooved wheel,
has at its opposite end another core, fitted in the shunt solenoid, in a similar manner
to the above series core, composed of brass tubing enclosing two metals, one iron and
the other lead, or any known non magnetic metal; more particularly referred to
hereinafter. The aforesaid chain has, at a determined position on the shunt solenoid
side, any known suitable brake attached in a moveable holder to permit of adjust-
ment. The aforesaid grooved wheel either is fixed rigidly at a short distance from
the centre of and on a spindle supported in brass bearings by brackets on the body
of the lamp, or fitted loosely on the said spindle, between two pulleys which are fixed
rigidly on the spindle at a short distance from its centre, as above mentioned; and
about the centre of the spindle we place a toothed wheel, over which passes a flexible
rack, one end of which passing down a tube, which serves as a guide, fitted on to the
body of the lamp, supports the upper or positive carbon holder, whilst the other end
of the flexible rack passing over a guide pulley through a hole in the body of the
lamp is fixed on to the lower or negative carbon holder, but is insulated therefrom in
the usual manner. The Negative carbon holder being guided by the usual guide rods.
And as we more heavily weight the upper carbon holder, the two holders are brought
together by the preponderance of this weight.

page_text: We so proportion the aforesaid series core, that when a current of known quantity
is passing through its solenoid, we get the predetermined lift of the weight or upper
carbon holder, and by decreasing the current to half the quantity we get a lift of
approximately half the distance, and so on; the aforesaid series core being about one
half of its length out of its solenoid when the carbons are together. The above
mentioned shunt core which is the same length as the series core is composed of
about one half of iron and one half of lead, the magnetic body being at the upper
end, and is about one quarter of its total length out of its solenoid when the carbons
are together.
Or, in another method, we have the series core the same as above mentioned, but
the shunt core has the non magnetic body at the top and the iron at the bottom, but
in other respects is similar to the above mentioned shunt core.
The action of the lamp when working is as follows.
When a current of known quantity is passed, through the lamp it flows also through
the series solenoid, and causes the said solenoid to exert a magnetic force, drawing
down the series core and with it the chain and brake which turns the grooved pulley,
thereby separating the carbons to the predetermined distance by means of the toothed
wheel and flexible rack, but as a portion of the current is flowing through the shunt
solenoid, this in its turn exerts a slight determined opposing magnetic pull and so
prevents the series core from separating the carbons with too great rapidity, until the
magnetic part of the shunt core is drawn nearly out of the solenoid to the determined
distance where the pull on the core is practically nil; therefore the current flowing
through the series solenoid causes the lower carbon holder to balance the upper, the
shunt solenoid and core, as hereinafter described, being simply used as a balance
weight to the series core, and also to increase the delicacy of the movement of the
series core.
Then as the Voltaic arc increases in length by the consumption of carbons, less
current passes through the said lamp circuit and the current diminishes in the series
solenoid, thereby allowing the balanced weight in the positive carbon holder to
descend and pull round the grooved pulley, and at the same time also permitting the
, magnetic part of the shunt core to reenter its solenoid, by reason of its weight. The
said shunt core then commences to exert a slight magnetic pull which increases
the delicacy of the movement of the series core. This motion still continues until the
shunt core is down low enough for the series core to release the brake, thereby letting
the wheel rotate under control of the balancing forces of the said proportioned
series core and the balanced weight; so maintaining a constant distance between the
points of the carbons.
The working of the second above mentioned method is as follows.
The action of the series solenoid in separating the carbons is the same as above;
also checked in a similar manner by the slight magnetic pull of the shunt solenoid,
as herein described for our first method; and a similar action to the first method goes
on until the shunt core is let down to the predetermined feeding position, then the
down progress
of the shunt core is arrested by reason of the magnetic part of the
said core being in the neutral part of the said shunt solenoid; then as the Voltaic Arc
increases in length by the consumption of carbons, less current passes through the
said lamp circuit, and the current diminishes in the series solenoid, and at the same
time, as the shunt core is suspended as above mentioned in the neutral part of the
said shunt solenoid, less pressure is brought to bear on the grooved pulley, thereby
letting the wheel rotate under control of the balancing forces of the said proportioned
series core and the balanced weight; so maintaining a constant distance between the
carbon points.

page_text: WALTER ROWBOTHAM of 39 Lever Street Manchester and FREDERIC STANHOPE
WORSLEY of 39 Lever Street Manchester Electrical Engineers 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 :-
In this invention as in Fig. 1, we employ two solenoid coils fixed, one on each side
of the body, A, of the lamp, the first wound with thick wire, a, connected in the
main circuit of the lamp, and known hereafter as the series solenoid, and the second
of fine wire, a', connected in a by pass to the lamp circuit and known hereafter as the
shunt solenoid.
In the series solenoid we fit a brass tube, b, with a determined freedom of movement,
enclosing a fixed iron core, c, more particularly referred to hereinafter.
At the top end of the said core we attach a chain, d, which passing over a grooved
wheel, e, and fastened thereto by a pin, t, as in Fig. 3, has at its opposite end another
Core, C, composed of brass tubing, 61, enclosing two metals one iron, c¹, and the
other lead, c², or any known non magnetic metal, hereinafter referred to more
particularly. The aforesaid chain has at a determined position on the shunt solenoid
side any known suitable brake, g, attached in a moveable holder to permit of
adjustment.
The aforesaid grooved wheel, e, is either fixed rigidly at a short distance from the
centre of and on a spindle, h, Fig. 2. supported in brass bearings i and j, by brackets
on the body of the lamp, or fitted loosely on the said spindle between two pulleys, k
and k¹, Fig. 4, which are fixed rigidly on the spindle at a short distance from its
centre as above mentioned, and about the centre of the spindle, h, we place a toothed
wheel, l, over which passes a flexible rack, m, Fig. 1. one end of which passing down
a tube, n, which serves as a guide, fitted on to the body of the lamp supports the
upper or positive carbon holder, o, whilst the other end of the flexible rack passing
over a guide pulley, p, through a hole in the body of the lamp is fixed on to the
lower or negative carbon holder, q, but is insulated therefrom in the usual manner.
The negative carbon holder being guided by the usual guide rods, r, and r¹.
And as we more heavily weight the upper carbon holder, o, the two holders are
brought together by the preponderence of this weight.
We so proportion the aforesaid series core, B, that when a current of known

page_text: quantity is passing through its solenoid, a, we get a predetermined lift on the weight
or upper carbon holder, o, and by decreasing the current to half the quantity we get
a lift of approximately half the distance and so on, the aforesaid series core, B,
being about one half of its length out of the solenoid, a, when the carbons are
together.
The above mentioned shunt core, C, which is the same length as the series core, B,
is composed of about one half of iron, c¹, and one of lead, c, the magnetic body, c',
being at the upper end, and is about one quarter of its total length out of the solenoid
when the carbons are together.
Or, in another method we have the series core, B, the same as above mentioned, but
the shunt core, C, has the non-magnetic body, c², at the top and the iron, c¹, at the
bottom, and in other respects is similar to the above mentioned shunt core, C, there
being only one wheel, e, Fig. 6. fixed on to the spindle, h, which is free to move under
the controlling forces of the chain, d, (which is loose in this case) and the magnetic
. pull of the two solenoids.
The action of the lamp when working is as follows.
When a current of known quantity is passed through the lamp it flows also through
the series solenoid, a, and causes the said solenoid to exert a magnetic force, drawing
down the series core, B, and with it the chain, d, and brake, g, which turns the
grooved pulley, e, thereby separating the carbons to the predetermined distance by
means of the toothed wheel, 7, and flexible rack, m, but as a portion of the current
is flowing through the shunt solenoid, a', that in its turn exerts a slight determined
opposing magnetic pull and so prevents the series core, B, from separating the carbons
with too great rapidity, until the magnetic part, c', of the shunt core, C, is drawn
nearly out of the solenoid, a¹, to the determined distance where the pull on the
core, C, is practically nil; therefore the current flowing through the series solenoid, a,
causes the lower carbon holder, q, to balance the upper, o, the shunt solenoid, a¹,
core, C, as hereinafter described being simply used as a balance weight to the
series core, B, and also to increase the delicacy of the movement of the series core
when feeding.
and
Then as the Voltaic Arc increases in length by the consumption of carbons, less
current passes through the said lamp circuit, and the current diminishes in the series
solenoid, a, thereby allowing the balanced weight, s, in the positive carbon holder, o,
to descend and pull round the grooved pulley, e, and at the same time also permitting
the magnetic part, c, of the shunt core, C, to reenter its solenoid, a', by reason of its
weight.
The aforesaid shunt solenoid core, C, then commences to exert a slight magnetic
pull which increases the delicacy of the movement of the series core, B. This motion
still continues until the shunt core is down low enough for the series core, B, to
release the brake, g, thereby letting the wheel, k, or wheels, as in Fig. 4., k, and, k¹,
Fig. 5, k, rotate under control of the balancing forces of the said proportioned series
core, B, and the balanced weight, s, so maintaining a constant distance between the
carbon points.
The working of our second above mentioned method is as follows.
The action of the series solenoid in separating the carbons is the same as above,
also checked in a similar manner by the slight magnetic pull of the shunt solenoid, a¹,
as herein described for our first method; and also similar action to our first method
goes on until the shunt core, C, is let down into the predetermined feeding position,
then the down progress of the shunt core, C, is arrested by reason of the magnetic
part, c', of the said core being in the neutral point of the said shunt solenoid, a.
Then as the Voltaic arc increases in length by the consumption of carbons, less
current passes through the said lamp circuit and the current diminishes in the series
solenoid, a, and at the same time as the shunt core, C, is suspended as above
mentioned in the neutral part of the said shunt solenoid, a¹, less pressure is brought
to bear on the grooved pulley, e, thereby letting the wheel rotate under control of
the balancing forces of the said proportioned series core, B, and the balanced weight, s,
so maintaining a constant distance between the carbon points.

page_text: Having now particularly described and ascertained the nature of our said invention,
and in what manner the same is to be performed, we declare that what we claim is
1. The herein described method of regulating the arc of an arc lamp by the
attractive influence of two solenoid coils on two determined proportioned cores of the
same length, one being all iron in a brass tube and the other about half iron and
half lead or any other nonmagnetic body in a brass tube, arranged in such a manner
that when the current passes through the lamp circuit both cores are affected by the
attractive influence of the solenoid coils, but just before the full arc is established the
core composed of iron and lead is not affected by the attraction of the solenoid,
the magnetic body being out of range of the attractive force. So enabling the full
are to be struck independently to its full extent with great promptitude by the
attractive force of the series solenoid on its core.
2. The herein described method of regulating the arc of an arc lamp by two
solenoids and cores arranged in such a manner that the shunt core is in the neutral
part of its solenoid at time of feed and so allowing the series core to regulate
the arc.
3. The construction of Electric Arc lamps with regulating solenoids having tight
fitting cores of equal length, the one being wholly of iron, the other being half iron
half lead, both enclosed in brass tubes, attached to each other by means of a chain
over a grooved pulley, fixed on a spindle having a pinion over which passes a flexible
rack, or free to move on a spindle controlling by means of a brake a fixed wheel or
wheels on said spindle having a pinion over which passes the said flexible rack, having
positive and negative carbon holder attached one at each end substantially as herein
described.