An Improved Method of and Apparatus for Regulating the Difference of Potential at the Terminals of Dynamo-electric and like Machines.
Year: 1898

page_text: Date of Application (in United Kingdom), 12th Dec., 1898
Complete Specification Left, 8th Sept., 1899-Accepted, 14th Oct., 1899
PROVISIONAL SPECIFICATION.
An Improved Method of and Apparatus for Regulating the Difference
of Potential at the Terminals of Dynamo-electric and like Machines.
I, LÉON DE COINCY, of 9, Avenue de l'Opéra, Paris, in the Republic of France,
Electrical Engineer, do hereby declare the nature of this invention to be as
follows:
The variations of energy, in a circuit utilised for the transmission of power,
or in the production of light, are generally obtained by means of apparatus such
as rheostats in the field-magnet circuit, resistances, etc., which consume energy
and which offer, in a large number of cases, numerous inconveniences and some-
times serious difficulties.
This invention relates to an improved method of and apparatus for regulating
the difference of potential at the armature terminals of dynamo-electric and
like machines, this being effected by the displacement of the armature on its
axis, thus obviating all the inconveniences and the difficulties which are pre-
sented by the other apparatus.
.
My improved method of regulation consists essentially as follows:-
Consider, for example, a receiving dynamo or motor mechanically operating
a generating dynamo for lighting, and having a ring armature. The armature
of the said generating dynamo is mounted on a hollow shaft capable of being
displaced longitudinally on the ordinary shaft whilst participating in the rotary
motion of the latter, this being effected by means of a feather or cams and a
groove.
This displacement is effected either by hand or by any suitable means,
electrical or mechanical; the arrangement adopted should moreover retain the
armature in a fixed position during its normal motion.
As long as the armature turns in its normal position, between the pole-pieces
of the field-magnet, the difference of potential at its terminals is that permitted
by the construction of the dynamo and the intensity of the current which results
therefrom corresponds to the resistance of the circuit, but accordingly as the
armature is displaced on the shaft, in moving out from the pole-pieces, the
difference of potential and the intensity diminish to become practically zero
when it is completely outside the said pole-pieces, whatever be the permanent
magnetism.
During the displacement of the armature, the dynamo-motor turns at its

page_text: constant velocity; but its expenditure of energy is proportional to the work
developed in the armature of the lighting dynamo (excepting of course the
constant expenditure necessitated by the passive resistances).
One thus obtains, when the variations of energy are frequent and consider-
able, an, important economy in the expenditure of energy, and an easy means of
proportioning it to the work done.
The armature can be displaced as above mentioned, either by hand, or by
or by any suitable means, electrical or mechanical.
I have shown, in the accompanying drawing, in principle, by way of example
only, two arrangements whereby, my said, invention may be carried conveniently
and advantageously into practice.
In the arrangement shown in Figure 1, I have supposed a receiving dynamo
or motor a mechanically driving a generating lighting dynamo b; the arma-
ture c of the latter is mounted, as mentioned above, on a hollow shaft d capable
of being displaced longitudinally on the motor-shaft e, whilst being capable of
turning therewith.
The hollow shaft d bears at its free end a soft iron sleeve f which is likewise
hollow, extending into the interior of a solenoid g, concentric with this shaft.
A current of suitable intensity (regulated by a liquid or solid resistance) can
be sent, at will, through the solenoid, which then attracts the soft iron sleeve f,
the hollow shaft d which is connected thereto, and the armature c.
An opposing spring h retains the armature in its normal position, when the
solenoid does not act.
In the arrangement shown in Figure 2, one of the ends of the hollow shaft d
can be connected to a centrifugal governor or regulator, the axis of rotation of
which coincides with that of the shaft.
This governor consists of four jointed arms, of which two are jointed to the
end of the shaft d and the other two to a fixed piece i.
The speed of rotation of the armature keeps the centrifugal pieces ; separated
from the shaft and, consequently, the armature c'is retained in its normal posi-
tion.
This governor or regulator carries between its arms, by means of springs k,
a solenoid g and two soft iron cores f.
A current of suitable intensity sent through the solenoid by means of a brush,
brings together as desired the cores f and, consequently, the centrifugal pieces j.
The arms of the regulator then approach the shaft, pushing away the hollow
shaft d, and the armature c is moved partially or entirely out from between
the pole-pieces.
The motion of translation of the armature can also be effected in the follow-
ing manner:
The armature-shaft bears a ring, capable of being actuated by a finger fixed
to the rod of a piston which operates parallel to the armature shaft in a closed
cylinder.
Into each end of the cylinder opens a pipe; cocks permit these two pipes
to be put alternately into communication, either with a reservoir containing
any suitable fluid under pressure (compressed air, water under pressure), or
with the external air.
A graduated motion of the piston is thus easily obtained and, consequently,
a graduated displacement of the armature on its axis. The speed of this motion
can be as rapid or as slow as is desired, since it depends only on the rate of
operating the cocks.
In cases where the operator has to control a number of dynamos, it will be
seen that the regulating board reduces itself to a simple panel on which are
fixed the distributing cocks.
This system of regulation by the displacement of the armature is not applic-
able to all forms of armatures, as for example, to disc armatures, but when the
form of the armature permits, it is applicable to alternate current dynamos,

page_text: as well as to continuous current dynamos, to monophase currents as well as to
polyphase currents.
It is applicable as well in cases where the armature is driven by an electric
motor as in cases where it is actuated by a mechanical motor!
F
An Improved Method of and Apparatus for Regulating the Difference
of Potential at the Terminals of Dynamo-electric and like Machines.
123 ...
-
..
:
I, LÉON DE COINCY, of 9, Avenue de l'Opéra, Paris, in the Republic of France,
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 ascer-
tained in and by the following statement:-
+
The variations of energy, in a circuit utilised for the transmission of power,
or in the production of light, are generally obtained by means of apparatus, such
as rheostats in the field-magnet circuit, resistances, etc., which consume energy
and which offer, in a large number of cases, numerous inconveniences and some-
times serious difficulties.
This invention relates to an improved method of and apparatus for regulating
the difference, of potential at the armature terminals of dynamo-electric and
like machines, this being effected by the displacement of the armature on its
axis, thus obviating all the inconveniences and the difficulties which are pre-
sented by the other apparatus.
My improved method of regulation consists essentially as follows:-
Consider, for example, a receiving dynamo or motor mechanically operating
a generating dynamo for lighting, and having a ring armature. The armature
of the said generating dynamo is mounted on a hollow shaft capable of being
displaced longitudinally on the ordinary shaft whilst participating in the rotary
motion of the latter, this being effected by means of a feather or cams and a
groove.
L
This displacement is effected either by hand or by any suitable means,
electrical or mechanical; the arrangement adopted should moreover retain the
armature in a fixed position during its normal motion.
As long as the armature turns in its normal position, between the pole-pieces
of the field-magnet, the difference of potential at its terminals is that permitted
by the construction of the dynamo and the intensity of the current which results
therefrom corresponds to the resistance of the circuit, but accordingly as the
armature is displaced on the shaft, in moving out from the pole-pieces, the
difference of potential and the intensity diminish to become practically zero
when it is completely outside the said pole-pieces, whatever be the permanent
magnetism.
During the displacement of the armature, the dynamo-motor turns at its
constant velocity; but its expenditure of energy is proportional to the work
developed in the armature of the lighting dynamo (excepting of course the
constant expenditure necessitated by the passive resistances).

page_text: One thus obtains, when the variations of energy are frequent and consider-
able, an important economy in the expenditure of energy and an easy means of
proportioning it to the work done.
The armature can be displaced, as above mentioned either by hand, or by
any suitable means, electrical or mechanical.
I have shown, in the drawing accompanying my Provisional Specification,
in principle, by way of example only, two arrangements whereby my said inven-
tion may be conveniently and advantageously carried into practice.
In the arrangement shown in Figure 1, I have supposed a receiving dynamo
or motor a mechanically driving a generating lighting dynamo b; the arma-
ture of the latter is mounted, as mentioned above, on a hollow shaft d capable
of being displaced longitudinally on the motor-shaft e, whilst being capable of
turning therewith.
The hollow shaft d bears at its free end a soft iron sleeve f which is likewise
hollow, extending into the interior of a solenoid g, concentric with this shaft.
A current of suitable intensity (regulated by a liquid or solid resistance) can
be sent, at will, through the solenoid, which then attracts the soft iron sleeve f,
the hollow shaft d which is connected thereto, and the armature c.
An opposing spring h retains the armature in its normal position, when the
solenoid does not act.
In the arrangement shown in Figure 2, one of the ends of the hollow shaft d
can be connected to a centrifugal governor or regulator, the axis of rotation of
which coincides with that of the shaft.
This governor consists of four jointed arms, of which two are jointed to the
end of the shaft d and the other two to a fixed piece i.
The speed of rotation of the armature keeps the centrifugal pieces ; separated
from the shaft and, consequently, the armature c is retained in its normal posi-
tion.
This governor or regulator carries between its arms, by means of springs k,
a solenoid g and two soft iron cores f.
A current of suitable intensity sent through the solenoid by means of a brush,
brings together as desired the cores f and, consequently, the centrifugal pieces j.
The arms of the regulator then approach the shaft, pushing away the hollow
shaft d, and the armature c is moved partially or entirely out from between
the pole-pieces.
The motion of translation of the armature can also be effected in the follow-
ing manner:-
The armature-shaft bears a ring, capable of being actuated by a finger fixed
to the rod of a piston which operates parallel to the armature shaft in a closed
cylinder.
Into each end of the cylinder opens a pipe; cocks permit these two pipes
to be put alternately into communication, either with a reservoir containing
any suitable fluid under pressure (compressed air, water under pressure), or
with the external air.
A graduated motion of the piston is thus easily obtained and, consequently,
a graduated displacement of the armature on its axis. The speed of this motion
can be as rapid or as slow as is desired, since it depends only on the rate of
operating the cocks.
In cases where the operator has to control a number of dynamos, it will be
seen that the regulating board reduces itself to a simple panel on which are
fixed the distributing cocks.
This system of regulation by the displacement of the armature is not applic-
able to all forms of armatures, as for example, to disc armatures, but when the
form of the armature permits, it is applicable to alternate current dynamos,
as well as to continuous current dynamos, to monophase currents as well as to
polyphase currents.

page_text: It is applicable as well in cases where the armature is driven by an electric
motor as in cases where it is actuated by a mechanical motor.
Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. The improved method of regulating the difference of potential at the arma-
ture-terminals of dynamo-electric and like machines, consisting in displacing
the armature axially relatively to the pole-pieces, substantially as and for the
purposes, herein before described.
2. The improved means for displacing the armature of a dynamo-electric or
like machine substantially as described with reference to either of the forms or
modifications shown in the drawing, for the purposes specified.
T
1900
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.
D. YOUNG & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.