Improvements in Apparatus for Regulating and Controlling Dynamos.
Year: 1894

page_text: Date of Application, 6th Feb., 1894
Complete Specification Left. 6th Nov., 1894-Accepted, 8th Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Regulating and Controlling
Dynamos.
I, WILLIAM MORRIS MORDEY, of 49 Queen Victoria Street, in the City
of London, Electrician, do hereby declare the nature of this invention to be as
follows:-
In dynamos, especially in those of the series type as used for the generation of
constant direct currents, one method of keeping the current constant when the
speed or external circuit is altered, is by a variable shunt on the field magnet
winding controlled either by hand or by some automatic device. In thus regulating
the current it is necessary to vary the position of the collecting brushes on the
commutator in order to avoid destructive sparking and improper working of the
machine. The object of this invention is to provide means for effecting this move-
ment of the brushes automatically such means being used in combination with
automatic field shunting devices.
In an arrangement for this purpose, the brushes which bear on the commutator,..
are mounted on a rocker or frame which is capable of movement about the same
centre as the commutator, such movement being sufficient to include the required
range of motion of the brushes. The rocker is attached to the movable part of"
an electro-magnet or solenoid and core, (hereinafter included in the expression
electro-magnet) the winding of which is in series with the resistance used as a shunt
on the field circuit of the dynamo. The position of the movable part of the said
electro-magnet and of the rocker is such that when no current is being shunted
from the field, the rocker is at the "backward" position on the commutator, or at
that position required for full excitation and full armature current.
When a
portion of the current is shunted from the field through a circuit comprising the
regulating resistance and the electro-magnet, the latter pulls the rocker round till
the brushes occupy the "forward" position required by the new conditions. The
variations in the current shunted from the field by the pull exerted by the electro-
magnet cause the rocker and brushes to assume the proper position for all
conditions within the range of output. The brushes assume the "backward"
position when no current is being generated, or when the full current is being
generated with a fully excited field.
The rocker and the electro-magnet may be connected by a suitably shaped cam
controlled by a weight or spring to give the required proportionality of movement,
the "forward" pull of the electro-magnet being exerted against the opposition of
the said weight or spring. The arrangement is such that the brushes assume the
most "backward" position when no current is being generated or when the full
current is being generated in a fully excited field-that is in a field from which no
current is shunted, and the "forward" pull taking place when the field is shunted,
and varying with the amount of current shunted.
Automatic regulators for the regulation of the fields of series dynamos are known
and the automatic shunting of the fields may be carried out by any of such
regulators. But the arrangement I prefer and which constitutes a part of this.
invention comprises a form of automatic regulator having a water resistance
arranged between electrodes of material such as carbon, platinum or lead and
forming a shunt on the field.
The variation of this resistance is effected by altering the distance between the
electrodes, the shunt circuit being broken by the withdrawal from the water of i
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1

page_text: one or both of the electrodes. As the liquid will become heated and vaporised,
means are provided for the purpose of maintaining its level constant. Suitable
means for this purpose is a water vessel closed at the top, communicating at the
bottom with the main vessel containing the electrodes, and acting after the manner
of the well known bird fountain.
Where decomposable electrodes are employed, a switch is provided for the
purpose of reversing the connections from time to time in order to equalise the
wearing away of the two electrodes.
The movement of the electrode or electrodes is effected by an electro-magnet in
the main circuit preferably controlled by a sensitive relay as described in the
Specification of Letters Patent No. 7953 of 1886.
Dated this 6th day of February 1804
COMPLETE SPECIFICATION.
Improvements in Apparatus for Regulating and Controlling
Dynamos.
I, WILLIAM MORRIS MORDEY, of 49 Queen Victoria Street, London E.C.,
Electrician, 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 dynamos, especially in those of the series type as used for the generation of
constant direct currents, one method of keeping the current constant when the
speed or external circuit is altered, is by a variable shunt on the field magnet
winding, controlled either by hand or by some automatic device. In thus regulating
the current it is necessary to vary the position of the collecting brushes on the
commutator in order to avoid destructive sparking and improper working of the
machine. The object of this invention is to provide improved means for effecting
this movement of the brushes automatically and in combination with automatic
field shunting devices.
In the accompanying drawings,
Fig. 1 is an end elevation showing the improved automatic rocker; and
Fig. 2 is a diagram showing the rocker in combination with an automatic field
shunting device.
Fig. 3 is an elevation to a larger scale showing a construction of regulator
according to this invention.
The brushes a which bear on the commutator are mounted on a rocker or
frame e which is capable of movement about the same centre as the said commutator,
such movement being sufficient to include the required range of motion of the
brushes. The rocker c is attached to the movable part d of an electro-magnet or
solenoid e the winding of which is in series with the resistance g used as a shunt.
on the field circuit h of the dynamo D. The position of the movable part d of the
said electro-magnet or solenoid and of the rocker c is such that when no current is
being shunted from the field the rocker is at the "backward" position on the
commutator, or at that position required for full excitation and full armature current.
When a portion of the current is shunted from the field h through a circuit
comprising the regulating resistance and the winding the latter pulls the rocker c
round till the brushes a occupy the "forward" position required by the new
conditions. The variations in the current thus shunted from the field, by varying.
the pull exerted by the electro-magnet, cause the rocker and brushes to assume the
proper position for all conditions within the range of output. The brushes assume.

page_text: the "backward" position when no current is being generated or when the full
current is being generated with a fully excited field.
The rocker and the electro-magnet are connected by a cam j that turns about a
centre and is provided with a prolongation that is suitably shaped, as shown,
and controlled by a weight K (or spring) to give the required proportionality of
movement, the "forward" pull of the electro-magnet being exerted against the
opposition of the said weight or spring. The arrangement is such that the brushes
assume the extreme "backward" position when no current is being generated or
when the full current is being generated in a fully excited field-that is in a field
from which no current is shunted, the "forward "pull taking place when the field
is shunted and varying with the amount of current shunted.
Automatic regulators for the regulation of the fields of series dynamos are known
and the automatic shunting of the fields may be carried out by any of such
regulators. But the arrangement I prefer and which constitutes a part of this
invention comprises a form of automatic regulator having a water resistance
arranged between carbon or platinum or lead electrodes forming a shunt on the
field. An arrangement of this kind is shown diagrammatically in Fig. 2 and to a
larger scale in elevation in Fig. 3.
The variation of this resistance is effected by altering the distance between the
electrodes or their depth of immersion, the shunt circuit being broken by the
withdrawal from the water of one or both of the electrodes. As the liquid will
become heated and vaporised, means are provided for the purpose of maintaining
its level constant. Suitable means for this purpose is shown in Fig. 3 and
comprises a water vessel m closed at the top, communicating at the bottom with the
main vessel M containing the electrodes and acting after the manner of the well
known bird fountain.
Where decomposable electrodes are employed I provide a switch n for the
purpose of reversing the connections from time to time in order to equalise the
wearing away of the two electrodes.
The movement of the electrode or electrodes is effected by an electro-magnet o
in the main circuit through the intervention of a lever p provided with dash
pots q and a counterbalance weight r, the said electro-magnet being preferably
controlled by a sensitive relays as described in Geipel's Specification No. 7953
of 1886.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. Apparatus for regulating and controlling a dynamo wherein the rocker
carrying the brushes is automatically operated by an electro-magnetic device the
winding of which is in series with the resistance used as a shunt on the field circuit
of the dynamo substantially as herein described.
2. Apparatus for regulating and controlling a dynamo comprising a rocker, an
electro-magnetic device for automatically operating the same, and an automatic
water regulator for controlling the field excitation, the whole constructed arranged
and operating substantially as described and shown.
Dated this 6th day of November 1894.
Аррисаць,
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.