Improvements in Apparatus for Regulating Electric Currents or Electric Potential.
Year: 1890

page_text: Date of Application, 22nd Dec., 1890
Complete Specification Left, 22nd Sept., 1891-Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION,
Improvements in Apparatus for Regulating Electric Currents or
Electric Potential.
We,
ALBERT GAY of 47 Gloucester Road, Brighton, in the County of Sussex,
Electrical Engineer, and ROBERT HAMMOND of 117 Bishopsgate Street Within,
n the County of London, Electrical Engineer do hereby declare the nature of this
nvention to be as follows:-
This invention has reference to regulating apparatus designed to maintain a
constant current or a constant potential between any two points of an electric
circuit, as for example between the terminals of a dynamo, transformer, or other
electric generator; and to means for rendering such apparatus dead beat in its action
and thereby prevent hunting of certain parts thereof.
The regulating apparatus comprises a resistance that is connected at its ends to
the two points between which a constant current, or constant potential is to be
maintained in the case of alternating currents this resistance may be inserted in
the exciter circuit, or as a shunt to the exciter field magucts; a contact arm or lever
(hereinafter called the regulator arm capable of cutting out or putting in circuit
more or less of the resistance according to the direction in which it is moved;
two electro magnetic devices for actuating the said regulator arm in opposite
directions and a relay adapted to bring one or other of these devices into action,
the relay being operated by a third electro-magnetic device the winding of which
is arranged either in parallel with the electric generator, or in series therewith
according as the apparatus is intended to maintain a constant potential, or a constant
current. The arrangement is such that when the current or potential between the
two points rises above the normal, the relay will operate to close the circuit of one
of the two first mentioned electro-magnetic devices, which will cause the regulator
arm to move and introduce more of the resistance into circuit, and when the current
or potential falls below the normal the relay will break the circuit of the first
mentioned device and complete that of the second which will then move the
regulator arm in the opposite direction so as to cut out or short circuit a part of
the resistance, thereby maintaining a constant or approximately constant current
or potential, as the case may be, between the two points desired. To make
the apparatus dead beat, a brake operated by another electró-magnetic device is
provided to arrest the regulator arm after that arm has been moved to cut out or
put in resistance.
According to one construction the resistance is made as a series of coils connected
to contact blocks after the manner of a regulator switch, and the regulator arm is
fixed to a spindle that is electrically connected to one end of the set of resistance
coils and carries two curved pieces of iron that serve as movable cores to two
solenoids. One end of each of these solenoids is connected to one of the
hereinbefore mentioned points or terminals, and the other ends of the solenoids are
each connected to one of two mercury cups. The relay comprises a horizontal
pivoted bar in electrical connection with the other point or terminal and, having
bent ends adapted to enter one or other of the mercury cups when the bar is inclined
in one direction or the other and to then complete the circuit of that solenoid the
one end of which is in connection with the mercury cup entered by the lowerniost
of the bent ends. To the bar is fixed a piece of iron that is bent to form part of
a ring the centre of which is at the centre of motion of the bar. This bent piece
of iron serves as a core to a similarly shaped fixed solenoid that is placed either in
a shunt between the hereinbefore mentioned points or terminal so as to be in parallel
with the electric generator, or is placed in series with the generator according as it

page_text: is desired to maintain a constant potential or a constant current. The pivoted bar
is provided with means such as an adjustable weight whereby it can be caused to
assume a horizontal position when the current strength or potential as the case may
be is at the desired normal; in this position it breaks the circuit of each of the
solenoids that operate the regulator arm.
A pivoted bar or stop operated in one direction by the movable core of a solenoid,
and in the other direction by a spring, serves, by being brought into the path of
one or other of a number of spring arms or blades on a spindle geared to the spindle
carrying the regulator arm, to bring this arm to rest after the same has been moved
to cut out or to put in resistance. The spindle carrying the spring arms or blades
may also be provided with a fan or fly to retard its motion.
To reduce the number of contact blocks connected to the resistance coils, the
outer end of the regulator arm may be made in two parts one of which is connected
to the other through a resistance.
Dated this 22nd day of December 1890.
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Regulating Electric Currents or
Electric Potential.
We, ALBERT GAY formerly of 47 Gloucester Road, Brighton in the County of
Sussex, but now of Kensington Central Electric Lighting Station, Richmond
Road, S. W. in the County of London, Electrical Engineer, and ROBERT HAMMOND
of 117 Bishopsgate Street Within, in the County of London, 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 ascertained in and by the following
statement :-
This invention has reference to an improved construction of regulating apparatus
designed to maintain a constant current, or a constant potential, between any two
points of an electric circuit, as for éxample between the terminals of a dynamo,
transformer, or other electric generator, and-to-means-for-rendering such apparatus
dead beat in its action and thereby prevent hunting of certain parts thereof.
The regulating apparatus comprises a resistance that forms part of a circuit in
which it is desired to maintain a constant current, or between sonie two points of
which it is desired to maintain a constant potential; in the case of alternating
currents this resistance may be inserted in the exciter circuit, or as a shunt to the
exciter field magnets; a contact arm or lever (hereinafter called the regulator arm)
capable of cutting out or putting in circuit more or less of the resistance according
to the direction in which it is moved; two electro magnetic devices for actuating
the said regulator arm in opposite directions; and a relay adapted to bring one or
other of these devices into action, the relay being operated by a third electro-
magnetic device the winding of which is arranged either in parallel with the electric
generator,-or-in-series-therewith-according as the apparatus is intended to maintain
a constant potential or a constant current. To make the apparatus dead beat, a
brake operated by another electro-magnetic device or by a thermo-electric device
is provided to arrest the regulator arm after that arm has been moved to cut out
or put.in resistance. The arrangement is such that when the current or potential
between the two points rises above the normal, the relay will operate to close the
circuit of one of the two first mentioned electro-magnetic devices, which will cause
the regulator arm to move and introduce more of the resistance into circuit, and
when the current or potential falls below the normal the relay will break the circuit
of the first mentioned device and complete that of the second which will then move

page_text: the regulator arm in the opposite direction so as to cut out or short-circuit a part
of the resistance, thereby maintaining a constant or approximately constant current
oi potential, as the case may be, between the two points desired.
According to one construction the resistance is niade as a series of coils connected
to contact blocks after the manner of a regulator switch, and the regulator arm is
fixed to a spindle that is electrically connected to one end of the set of resistance
coils and carries two curved pieces of iron that serve as movable cores to two
solenoids. One end of each of these solenoids is connected to one of the herein-
before mentioned points or terminals, and the other ends of the solenoids are
cach connected to one of two mercury cups. The relay comprises a horizontal
pivoted bar in electrical connection with the other point or terminal and having
bent ends adapted to enter one or other of the mercury cups when the bar is
inclined in one direction or the other, and to then complete the circuit of that
solenoid the one end of which is in connection with the mercury cup entered by
the lowermost of the bent ends. To the bar is fixed a piece of iron that is bent to
form part of a ring the centre of which is at the centre of motion of the bar. This
bent piece of iron serves as a core to a similarly shaped fixed solenoid that is placed
either in a shunt between the hereinbefore mentioned points or terminals so as to be
in parallel with the electric generator, or is placed in series with the generator
according, as it is desired to maintain a constant potential or a constant current.
The pivoted bar is provided with means such as an adjustable weight whereby
it can be caused to assume a horizontal position when the current strength or
potential, as the case may be, is at the desired normal; in this position it breaks
the circuit of each of the solenoids that operate the regulator arm.
A. pivoted bar or stop operated in one direction by the movable core of a solenoid,
and in the other direction by a spring, serves, by being brought into the path of one
or other of a number of spring arms or blades on a spindle geared to the spindle
carrying the regulator arm, to bring this arm to rest after the same has been moved
to cut out or to put in resistance. The pivoted bar or stop may also be moved in
one direction by the expansion of a wire heated by an electric current, and in the
other direction by the contraction of the wire. The spindle carrying the spring
arms or blades may also be provided with a fan or fly to retard its motion.
Referring to the accompanying drawings,
Fig. 1 is a diagrammatic view of the apparatus arranged for regulating electric
potential according to this invention.
Figs. 2 and 3 are respectively elevation and plan of the relay.
Fig. 4 is a plan of a resistance with a regulator forming part of this invention.
Fig. 5 is a side elevation of the same;
Fig. 6 is a perspective view of the electro magnetic brake, and a fan or fly; and
Fig. 7 shews a modification of the contact arm or lever.
a, b, are the poles of an electric generator or other source of electric energy to
which are connected the leads a, a, b, b¹, respectively in which it is desired to
maintain a constant current; or between any two points such as 1, 1 of which it
is desired to maintain a constant potential. In shunt with these leads between the
points 1, 1 there is a solenoid 2 in which there moves a curved core 3.
When a
constant current is to be maintained in the circuit, the coil 2 forms part of the
circuit instead of being arranged as a shunt thereto as shewn. The core 3 is connected
by non-magnetic arms with a pivoted bar 4 capable of dipping at its ends into
mercury cups 5 and 5º. The cup 5 is connected through a solenoid 6 to the
terminal of the generator. The cup 5ª is connected through the solenoid 7 to the
same terminal; the bar 4 is connected to the other terminal a of the generator and
consequently when the bar 4 is dipping into either of the mercury cups there is a
complete circuit from one terminal of the generator to the other, through one or
other of the solenoids 6 and 7. 8, 8, 8 are a series of resistances, included in the
circuit between the points 1, 1" of which a constant pressure is to be maintained.
A regulator arm 9, connected electrically to one terminal of the resistance moves
over the contacts of the resistance, and serves to short-circuit some or all of them,

page_text: except when it is at the left hand end of the series. This regulator arm is pivoted
at 10, and is moved or controlled by the cores 6 and 7 of the solenoids 6 and 7
respectively.
Turning now to the detail drawings of the relay it will be seen that the bar 4 bas
the current conveyed to it by a blade 11 moving-in a cup 12, filled with mercury.
The bar itself is carried between centres 13, 13, and moves with very little friction.
It is balanced by an adjustable weight 14 which can be moved by a screw 15, which
16 is a
has a milled head at each end, and is carried in bearings on the bar 4.
non-magnetic semi-circular arm carrying the core 3 which is capable of moving
within the solenoid 2. The motion of this core is thus communicated to the bar 4.
At each end of the bar is a contact piece 4" and 4" which can dip into the mercury
cups 5 and 5ª on the stands 17 and 17, which are connected to the terminal b
through-the solenoids 6 and 7 as already explained.
Each coil of the resistance is connected to a contact block -18. These pieces are
arranged in an arc over which there sweeps the regulator arm 9 having at its end
an elastic contact-making device 9º. This regulator arm is pivotted to a spindle 19
to which are attached arms 20 and 21, carrying the solenoid-cores 6 and 7" moving
within the solenoids 6 and 7 respectively (Figs. 1 and 5). At the lower part of the
spindle is a wheel 22 gearing with a pinion 23 on the spindle 24 of the fan 25. This
fan serves to damp the motions of the regulator arm and render them dead beat.
When great steadiness of action is desired we employ an electro magnetic brake
such as that shewn in Fig. 6. In this arrangement the spindle 24 carries, in
addition to the fan 25, the elastic arms 26 radiating from a boss. A stop or
abutment.27 is provided, and is so arranged that when the current or pressure, as
the case may be, in the circuit to be regulated is normal,-the-stop or abutment
stands in the path of the elastic arms, and opposes itself to their rotation. At
other times it stands out of their path-and-offers-no-resistance. The position of the
stop or abutment is determined by the action-of-the-solenoid-28, in which is a
core 29, guided by a spindle 30, and supported by-a-spring 31. Any change in the
strength of the current, passing through the solenoid alters the position of the
stop 27.
When the pressure in a circuit is being regulated the solenoid 28 is
connected as a shunt to the circuit but when current is to be regulated the solenoid 28
is-included in the circuit.
To reduce the number of contact blocks-18-connected-to-the-resistances 8, the
outer end of the regulator arm 9 may be made in two parts 9, 9b, as shewn in
Fig. 7, one of which viz.-9-is-connected to the other through a resistance 9° and so
shunts each resistance coil 8 before entirely cutting it out or putting it in.-
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what
we claim is :-
1. In apparatus for regulating electric currents, or electric potential, the com
bination with a relay and an adjustable resistance, of an electro-magnetic device
controlled by the said relay and serving to put more or less of the resistance inte
or out of circuit, and a brake (with or without a fan) for controlling the motion o
the said electro-magnetic device substantially-as-described.
2. Apparatus for regulating electric currents or electric potential, constructed
and operating substantially as described with reference to the drawings.
Dated this 21st day of September 1891.
W. Lloyd Wise,
ALBERT GAY,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicants.