Improvements in Methods and Means for Electric Regulation of Power.
Year: 1896

page_text: Date of Application, 4th Aug., 1896-Accepted, 7th Nov., 1396
COMPLETE SPECIFICATION.
Improvements in Methods and Means for Electric Regulation of
Power.
We, HORACE BIGELOW GALE, of No. 12 West Thirty-first Street, in the
City of New York, State of New York, United States of America, Electrical
Engineer, and CHARLES TROTTER THOMPSON, of No. 2116 Spruce Street, in
the City of Philadelphia aforesaid, Mechanical 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 :-
The following is a specification of our said invention, reference being had to the
accompanying drawings.
The invention relates to the regulation of the speed and power of prime-movers,
such as steam, gas and oil engines, water-wheels, windmills, and the like, in cases
where either the work or the source of power or both may be variable, and in
which a dynamo-electric machine is employed to adjust the net load on the prime
mover to correspond with the supply of working fluid,-this system of regulation
being the opposite of the usual system, in which the supply of working fluid is
adjusted to correspond with the load.
:
The present invention constitutes especially an improvement on that covered by
British Patent No. 7119, dated April 10th, 1894, entitled "Speed and power
regulators for motors," though the new method is applicable also to certain cases
not covered by that patent..
In previous applications of the system of regulation to which the improvements
relate, various methods of compound-winding on the regulating dynamo have been
employed, in order to produce the changes in electromotive-force required to
compensate for the variations of the current in its armature and external circuit;
and it has been found that, while such a method is capable of compensating
perfectly for extreme fluctuations in the working load, and for the changes of
voltage on the regulating circuit which arise from and accompany such
fluctuations, there are also in ordinary practice variations of voltage, on the
regulating circuit which arise from other and independent causes, and which.
cannot be perfectly compensated for by a compound-winding. Such variations of
voltage may result, for example, from chemical changes in the storage battery due
to long continued charging or discharging, or from changes in the working rate
of other dynamos which may be connected to the same battery; and their
effect, unless compensated for, is to produce corresponding variations in the speed
of the regulating dynamo and the connected machinery, and in the rate of work of
the prime-mover.
The main objects of the present improvements are to compensate automatically
for all such variations of voltage, from whatever cause they arise, by producing
similar variations in the electromotive force of the regulating dynamo, and thus to
secure more perfect regulation of load and speed in the prime-mover than is
generally possible without these improvements.
To accomplish these objects we employ a field rheostat, adjustable brushes, or
equivalent adjustable mechanism adapted to vary the electromotive-force of the
regulating dynamo, and the mode of operation consists in shifting this mechanism
automatically in response to .fluctuations in the load on the prime-mover, so as to
vary the rate of work of the regulating dynamo in such a way as to again equalize
the load. By this method, the resultant load on the prime-mover is continuously

page_text: adjusted to equilibrium with its driving effort, independently of the operation of
the compound-winding, and irrespective of normal fluctuations either in the load
or the driven machinery, in the source of power; or in the voltage of the regulating
circuit and consequently 'the desired speed of the connected machinery is
maintained under all working conditions.
The accompanying drawings illustrate diagrammatically suitable means by
which the improved method of regulation may be applied to prime-movers of
various types and under various conditions of work.
Fig. 1 illustrates the general case of a piston engine applied to any variable
work, and in which fluctuations in the working load, in the source of power, and in
the voltage of the regulating circuit, are all to be provided for;
Fig. 2 shows a similar case for a water-wheel used to drive an electric-lighting
plant;
Fig. 3 represents an electrical-power-transmission plant, with a water-wheel as a
prime motor, and illustrates an application of the method to a case where the
source of power and the voltage of the regulating circuit are nearly constant, and
the only fluctuations to be provided for are in the working load; and
Fig. 4 illustrates the preferred method of applying the invention; namely, in a
combination including an independent governing mechanism adapted to control
the supply of working fluid to the prime-motor, a storage. battery, and a special
device adapted to vary the rate of work of the prime-motor according to the state
of the charge in the battery.
Similar characters indicate corresponding parts in the different figures.
P indicates the prime-mover, W the shaft which drives the working load, A the
armature of the regulating dynamo, and R the group of automatic mechanism for
varying the electromotive-force thereof.
In Fig. 1, the prime-mover, P, is symbolized as a steam engine, connected to
drive the shaft, W, by means of the pulleys, p, and a belt, b. The shaft, W, in
this figure, may be taken to represent, for example, the main shaft of a mill or
factory, subjected to a variable working load of driven machinery. The regulating
dynamo, A, also, is belted to the work-shaft, W, and is electrically connected to
the regulating circuit, C, in which is an external source of electromotive-force, S,
-for example, a storage battery.
The main field-magnetizing coil of the regulating dynamo which, in Fig. 1, is
in a shunt from the armature circuit, indicated by f; and r indicates a resistance
in the field-circuit, which is variable by means of the rocking contact-arm, l. The
latter forms an armature for the two electro magnets, m', and m², whose exciting
circuits, e¹, and e², are normally kept open but may be respectively closed by the
contact-maker, c, operated by the centrifugal governor, g, connected with the
. engine.
The governor, g, may be taken to represent, either the governor regularly
applied to the steam engine for the purpose of controlling the steam supply, and
to which the contact-maker, c, is attached, or it may be a special governor whose
sole function is to operate the contact-maker, c.
f¹, indicates an auxiliary field-coil, which, in Fig. 1, is in series with the
armature A.
.
The method of operation of the apparatus may be explained as follows:
Referring to Fig. 1, suppose the load applied to the shaft, W, for the time being
to be just sufficient to balance the effort exerted by the prime-motor, P, when
running at its normal speed and power, and that the rheostat-arm, l, is adjusted so
that the electromotive-force generated in the armature, A, is just sufficient to
balance the counter-electromotive-force on the external circuit, C. Under these
circumstances, no current will flow in the armature, A, and no work will be done
thereby. If the load, or a portion of it, is suddenly thrown off the shaft, W, the
speed of the prime-motor and the connected machinery will tend to increase; but
the slightest increase in the speed of the armature, A, will overbalance the
counter-electromotive-force of the circuit, G, and the armature will begin to

page_text: generate a current, thus applying a load to the prime motor in compensation for
that thrown off. Similarly, if a load beyond the normal capacity of the prime-
motor is thrown on the shaft, W, the momentary diminution of speed, which
follows, will cause the external electromotive-force on the circuit, C, to
predominate, and a current will flow in the reverse direction through the
armature, A, causing it to act as a motor, assisting the prime-mover to carry
the increased load.
The operation of the apparatus, in so far as it has been described, is the same
as that set forth in the patent already cited. The series field-coil, f, also, is
arranged to operate in the manner therein set forth, being preferably so wound and
proportioned that the variations in speed required to restore the equilibrium of
load and power in the prime-mover, after such changes in work as have been
described, are extremely small.
But, as before explained, the compound-winding will not compensate for
variations in the voltage of the circuit, C, which may occur independently of a
change in the current on that circuit; for example, on account of gradual changes
in the electromotive-force of the battery, or other source, S. Such a variation in
the voltage of the external circuit, C, will disturb the equilibrium between that
and the armature, A, and, unless the electromotive-force of the latter is given an
artificial variation to correspond with that on the circuit, its rate of work will be
altered, so as to change the resultant load on the prime-mover.
To produce this required variation in the electromotive-force of the regulating
dynamo, automatically, every such slight variation in the load on the prime-mover
is made to set in motion a shifting mechanism, R, which raises or lowers the
electromotive-force of the armature, A, so as to correspond with the altered
voltage on the circuit, C, thus restoring the equilibrium of load and power in the
prime-mover.
The automatic mechanism, R, may be made directly responsive to changes of
load, or indirectly responsive, through one or other of the effects which usually
accompany such changes. Thus, Fig. 3, to be hereafter explained, illustrates a
case in which the changes of load act directly on the mechanism, R; Fig. 2,
a case in which the effect is produced by resulting changes of voltage; while, in
Fig. 1, the small changes of speed which follow changes in load are utilized to
control the mechanism for varying the electromotive-force of the regulating
armature.
Referring to Fig. 1, if a working load in excess of the power of the prime-
mover, P, is kept on the shaft, W, so as to cause the battery, S, to discharge
steadily for a considerable time, there will be a gradual fall in the electromotive-
force of the battery, which will tend to diminish the motor work of the armature, A,
and to throw a correspondingly increasing load upon the prime-mover P. This
increase in the resultant load will tend to diminish the speed of the prime-mover;
but an extremely slight diminution in the speed will cause the governor, g, to lower
the contact-maker, c, sufficiently to close the circuit, e', energizing the magnet, m',
and moving the rheostat-arm, 7, toward the left. This operation increases the
resistance in circuit with the field coil, f, and thus weakens the field and diminishes
the electromotive-force of the armature, A, to correspond with the diminishing
voltage of the circuit, C, so as to cause an increase in the motor current of
the armature, A. The rheostat-arm, Z, will continue to move toward the left,
diminishing the electromotive-force of the armature, A, until the increasing motor
work of that armature removes the excess of load from the prime-mover, allowing
it to resume its normal speed and rate of work. The contact-maker, c, is then
held in an intermediate position between the contacts, 1 and 2, as shown, and the
rheostat-arm, l, remaining stationary.
It is evident that a rise in the electromotive-force of the source, S, would tend,
on the contrary, at first to increase the motor work of the armature, A, (or to
diminish its work as a generator, as the case may be,) and thus to lighten the load
on the prime-mover, causing an increase of speed; and that a slight increase would

page_text: bring the contact-maker, c, to close the circuit, e, energizing the magnet, m³, and
thus producing the reverse compensating effect from that previously described on
the mechanism, R, and again restoring the normal load on the prime-motor.
The speed of the connected machinery is thus maintained, not by adjusting the
supply of working-fluid in the prime-mover to correspond with the load, but by
adjusting the net load on the prime-mover to equilibrium with its normal effort-
thus maintaining a uniform, or nearly uniform, rate of work in the prime-mover.
If the governor, g, also controls the point of cut-off in the steam cylinder, the
effect is to maintain a fixed point of cut-off, determined by the normal position of
the contact-maker, c, between the contacts 1 and 2. The latter may be made
adjustable by a screw, 3, by means of which the point of cut-off may be set to any
desired part of the engine stroke.
A dash-piston, d, is carried by the arm, 4, attached to 1, to prevent too rapid or
extreme movements of the rheostat. It is apparent that the principle of operation
of the mechanism, R, makes it capable of compensating for variations in the net
load of the prime-motor, from whatever cause they arise, whether from changes in
the voltage of the external circuit, C, as just described, or from changes in the
working load on the shaft, W. The automatic regulator, R, therefore may be
employed either with or without the series coil, fi; but we prefer to employ it in
combination therewith, as a supplementary device, whereby the errors incident to
the older method of regulation are corrected.
The best results are attained by the latter arrangement, because it is difficult to
make a shifting mechanism sufficiently quick in action to compensate for sudden
and violent fluctuations of the working load, and at the same time sufficiently
steady, and sensitive to small variations; but, by the use of the compound-winding
and the shifting mechanism in combination, as illustrated in Fig. 1, all these
qualities are secured. The series coil, f, in its effect upon the field of the
dynamo, A, responds instantly to sudden changes of load, however great; while
the shifting mechanism, R, following more slowly, secures accuracy of adjustment,
by correcting any small remaining variations in the resultant load on the prime-
mover, P, from whatever cause arising.
This method of regulation is applicable to cases in which not only the working
load, but also the source of power, is subject to variations, as in the case of a
windmill, the mode of operation in such a case being the same as has been
described.
We do not restrict our claims herein to the use of the compound-winding and
shifting mechanism in combination, because, in certain cases, where the fluctuations
of load are not too sudden or violent, the series field-coil, f', may be safely
omitted.
It is apparent also, that instead of a rheostat, r, in the field circuit as a means of
varying the electromotive-force of the regulating dynamo, A, any known equivalent
device, operable in a similar manner by a shifting mechanism, such as commutable
field-coils, shifting brushes, or other equivalent means known in the art-may be
substituted without departing from the principle of the invention. Thus, for
example, in Fig. 1, by prolonging the arm, 4, and connecting it by a link, 5, with
the brush quadrant, 6, (as indicated by dotted lines,) the same mechanism, R, may
be made to shift the position of the brushes, 7 and 8, and thus vary the electro-
motive-force of the armature, A.
Figs. 2 and 3 illustrate some of the possible variations in the detailed devices by
which this method of regulation may be applied in different cases.
In Fig. 2 the prime-motor, P, is symbolized as a water-wheel, and the variable
working load is furnished by a dynamo, D, driven from the work-shaft, W, and
supplying current to electric lamps, L.
Here the variations in the working load are made to act upon the shaft
mechanism, R, by means of the accompanying changes in the voltage of the lamp
circuit, 9. Connected between the mains of that circuit, is a high resistance
solenoid, g', having a movable core, 11, operatively connected to the lever, l,

page_text: which is applied to vary the electromotive-force of the regulating armature, A, by
rotating the brushes 7 and 8. A weight, 12, balances the pull of the solenoid, g',
at the normal voltage, and acts also as a dash-piston to prevent sudden and
extreme movements of the brushes.
An addition to the load causes a drop of voltage in the mains, 9, weakening the
solenoid, g', and permitting the weight 12 to move the brushes backward, which
diminishes the electromotive-force of the regulating armature, A. The electro-
motive-force on the circuit, C, (which is shown as connected to the same source as
in Fig. 1) is thus allowed to predominate, and the increased motor current through
the armature, A, assists in driving the dynamo, D, and thus removes the excessive
load from the prime-motor, P. When the resultant load on the prime-motor is
again brought into equilibrium with its driving effort, and the voltage is brought
up to the point where the pull of the solenoid again balances the weight, further
movement of the brushes is stopped, and the equilibrium between load and power-
in the prime motor is maintained.
The regulation of the load in that case does not involve the maintenance of
uniformity either in speed or in voltage, the control of the former depending upon
the construction of the dynamo, D, and the latter upon the winding of the
solenoid, g', and the form of the core, 11.
In Fig. 2, the compound field-coil, f, which assists the shifting mechanism, R,
in compensating for changes in the working load, is shown connected in the work
circuit, 9, instead of the regulating circuit, C, as in Fig. 1. Its office and effect
are however substantially the same in both cases, as the variations of current are
practically simultaneous in the two circuits. Through the influence of the coil, f',
which in the arrangement of Fig. 2, is wound in opposition to the coil, f, any
change in the working current on the lamp circuit, 9, has an instantaneous com-
pensating effect on the field of the regulating dynamo, A, and the shifting
mechanism, R, has only a corrective function to perform in adjusting the electro-
motive force of the said dynamo to compensate for any remaining sources of
variation, as previously explained.
The combination of a compound-winding with the shifting mechanism has here
an additional advantage, as the necessary movement of the brushes in this
arrangement is much less than would be required if the entire regulation devolved
upon the mechanism, R, and the sparking which would accompany excessive
movement of the brushes is thus avoided. In Fig. 3, the prime-motor, P, is
represented as a water-wheel, from which power is transmitted by means of a
dynamo, D', and the circuit, 13, to a number of electric motors, M, which do a
variable work. The regulating dynamo, A, is here symbolized as a separately
excited machine, having its field-winding, f, energized by the dynamo, D', and
without any series winding, the entire regulation being accomplished by the
shifting mechanism, R, which here operates by varying the resistance, r, in the
field circuit.
The rheostat-arm, 2, turns on a fixed pivot at the point 10, and is operated by a
solenoid, g, which is connected in series with the working circuit, 13, so that
changes in the load act directly upon the shifting mechanism, without the
intervention of secondary effect, such as changes in speed or voltage.
The pull of the solenoid, g, is here opposed by a spring, 15, the arrangement of
the parts being such that the greater the current flowing in the circuit, 13, the
greater is the resistance inserted in the field circuit of the regulating dynamo, A.
By this means a definite relation is maintained between the working load on the
dynamo, D', and the electromotive-force of the regulating armature, A; and by
properly graduating the resistance, r, the relation is made such as to maintain a
nearly constant load on the prime motor.
This arrangement is especially adapted to cases where the electromotive-force
on the regulating circuit, C, and the driving effort of the prime-mover are
approximately constant, the working load being the only variable factor. This is

page_text: the case, for example, when the circuit, C, is a constant potential lighting circuit,
the energizing source, S, being a central station, and when the head of water
acting on the prime-motor, P, is also constant. The result of slight variations in
the head, or in the voltage on the circuit, C, in this arrangement would be to cause
slight variations in the speed; which might, however, be corrected, if desired, by
occasional small hand adjustments in the gate, 14, controlling the supply of working
fluid to the prime-motor.
The details of the connections between the various governing devices, I, I', 9³,
and their respective shifting levers, 1, 1, and 12, are unessential to the invention,
and may be readily varied. Thus, it is obvious that any of these types of
governing devices may be connected to operate the shifting mechanism either
directly, as in the case of the solenoids, g' and g2, or indirectly, through a contact-
maker and electro-magnets, as in the case of the governor, g, in Fig. 1, the
arrangements shown being selected as illustrative of the variety of connecting
devices that may be employed.
Fig. 4 illustrates in detail the devices which we prefer to use in most cases in
applying this method of regulation to prime-inotors doing general work. The
prime-motor, P, is symbolized as a jet water-wheel or impulse engine, supplied with
working fluid through the pipe, 16, and connected by pulleys, p, and belts, b, to
the work-shaft, W, which may carry a variable load of any kind. A indicates
the regulating armature, having a shunt field-winding, f, in circuit with
a variable resistance, r, which conveys the main field exciting current, and an
auxiliary winding, f, in series with the armature, A, and arranged to compensate
for changes of load, as before described. A rheostat, r, in shunt with the series
coil, f, may be used to adjust the effect of the latter.
In the supply pipe, 16, is a throttle-valve, 17, controlled by a centrifugal
governor, H, operated in the manner usual in such governors; that is, the balls, 18,
will stand at a certain height corresponding to a certain rate of speed, and at
different speeds will stand at different heights,-a certain range of speed-variation
being required to open and close the valve, 17.
At R, in Fig. 4, is indicated the preferred construction of the automatic
mechanism for controlling the electromotive-force of the regulating armature, A.
The shaft, 19, is mechanically connected with the prime-motor (being in this case
driven by a belt, &, from the work-shaft, W,) so as to revolve at a proportional
rate of speed therewith. The shaft, 19, is geared also to the wheel, 20, which
carries an eccentric pin, 21. The latter engages the forked lever, 22, which is
loosely mounted on the shaft, 23, and imparts to the lever, 22, an oscillating
motion about that shaft as an axis. The lever, 22, carries on its two upper
branches a pair of pawls, 24, 25, capable of engaging the ratchet-wheel, 26, by
which motion may be imparted to the shaft, 23. The shaft, 23, is connected so as
to move the rheostat-arm, l, or equivalent device used to vary the electromotive-
force of the armature, A. We generally arrange the rheostat-arm to be carried
directly on the shaft, 23, but to avoid confusion in the diagram, it is here represented
as connected therewith by a band, 27, and pulleys, 28 and 29. Either arrangement
may be used in practice, according to convenience.
The pawls, 24 and 25, are normally supported out of contact with the teeth of
the wheel, 26, by the pins, 30 and 31, carried by the double-armed lever, 32,
which is pivoted on the axis, 33. By rocking this lever to the right or left, one or
other of the pawls will be lowered into engagement with the ratchet-wheel, 26, so
that the shaft, 23, and the rheostat-arm, l, will be moved step by step in one or the
other direction, as the lever, 22, oscillates.
The engagement and disengagement of the pawls, 24 and 25, are controlled by a
special centrifugal governor, g. This comprises the weights, 34 and 35, which are
pivotally hung from the revolving head, 36, driven by the bevel gears, 37 and 38,
from the shaft, 19. The arms, 39 and 40, which support the revolving weights, 34
and 35, bave inwardly projecting ends, which engage the slots, 41 and 42, in the

page_text: cylindrical dash-piston, 43. The latter is connected with the tappet-lever, 32, by
means of the rod, 44, which passes through the hollow centre of the revolving
head, 36.
The mechanism is enclosed in a cylindrical case, 45, which is filled with oil to
about the level of the gear, 38, so that the governor, g, revolves in a bath
of oil.
When the electromotive-force of the regulating armature, A, is so adjusted that
the resultant load on the prime-motor, P, exactly balances the driving effort
exerted thereon by the working fluid at the normal speed, the speed will remain
constant, the weights, 34 and 35, taking such position that the pawls, 24 and 25,
are both supported clear from the wheel, 26, so that no motion is imparted to the
rheostat-arm, !. The slightest variation in the load on the prime-motor will
however produce a variation of speed sufficient to slightly change the position of
the weights, 34 and 35, thus throwing into action one of the pawls, 24 and 25, and
moving the rheostat-arm, l, until the lost equilibrium is restored.
The governor, g, is so proportioned as to operate with a very much smaller
range of speed-variation than is required to operate the governor, H, so that the
latter is held in a nearly fixed position; thus maintaining practically a constant
opening of the supply valve, 17, and a nearly uniform rate of work in the
prime-mover, whatever the load thrown upon the work-shaft, W. The surplus
power is absorbed by the storage battery, S, when the load on the shaft, W, is
below the average, and restored through the motor action of the armature, A,
when the load exceeds the normal capacity of the prime-motor, as previously
explained.
The governor, H, serves also as a safe-guard to the machinery, in case of any
failure of the electrical load-regulating apparatus.
For the economical regulation of this system of regulation, where a storage-
battery is employed as the external source of electromotive-force, the prime-mover
must supply continuously an amount of power sufficient to meet the average
demand; otherwise the battery would ultimately become completely discharged;
or, if the power supplied were ou the average excessive, the surplus would be
wasted in overcharging. This requirement may be met by a hand adjustment of
the supply of working fluid at intervals, according to the state of charge of the
storage-battery; but it is desirable to make this adjustment automatic,-a result
which is accomplished, in the arrangement shown in Fig. 4, by the combination of
the two governors, g and H, operative with different ranges of speed variation, an
auxiliary spring, 46, connected with the governor, g, and automatic means for
varying the tension of that spring, according to the position of the rheostat-arm, l..
The tension-spring, 46, is held at one end by an arın, 47, attached to the tappet.
lever, 32, in such a manner as to exert an upward force on the rod, 44, and thus
opposes the centrifugal, force of the weights, 34 and 35, which is exerted down-
ward on the dash-piston, 43. The other end of the spring is attached to a cord,
which is wound on the cam, 49, carried by the arm . The effect is to increase
the tension of the spring, 46, as the arm, l, is turned in the direction required to
diminish the resistance in the circuit with the field, f, and to relieve the tension in
the spring as that resistance is increased. The governor, g, will therefore attain
equilibrium at slightly different speeds, according to the position of the arm Z.
with
For example, as the battery, S, approaches the economic limit of discharging,
its voltage rapidly falls, and the resistance, r, in the field-circuit, f, is increased,
so as to bring down the electromotive-force in the regulating armature, A, to
correspond with the voltage of the battery, as previously explained in connection
1. This diminishes the tension of the spring, 46, so that equilibrium is
attained at a speed slightly below the normal rate. This lower speed causes the
weights of the governor, H, to stand in a lower position, thus increasing the
supply of working fluid to the motor, and diminishing the draft on the battery, so
that it will not be discharged beyond its economic limit. If, on the other hand,
the tendency is to overcharge the battery, the rheostat-arm l, will be carried to

page_text: near its extreme lower position, which produces an opposite effect on the spring. 46,
and governor, H, diminishing the work of the prime-mover, and preventing over-
charging of the battery.
When the battery and prime-motor are properly proportioned to the work, these
extreme conditions are seldom approached, the effect of the combination being to
maintain automatically a nearly uniform rate of work in the prime-motor, P,
corresponding to the average demand for power, unaffected by the temporary
variations in the work on either side of the average. Sudden and violent
fluctuations in the working load are provided for by the compound-winding of
the regulating dynamo, and the slower variations in voltage on the circuit, C,
due to changes in the electromotive-force of the battery, or other source, S, are
compensated for by the automatic mechanism, R,-the entire combination forming
a completely automatic system of power regulation.
From the examples that have been shown, (which are typical and not restrictive,)
it is apparent that the details of the devices, by which this method of regulating
the load and speed of prime-movers may be applied in different cases, are capable
of numerous variations, without departing from the essential method involved in
the invention, and therefore we do not confine the claims to the particular
einbcdiments shown and described.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The method of maintaining a substantially uniform load on a prime-mover
applied to variable work, which method consists in augmenting or opposing the
driving effort, as may be required, by the torque of an auxiliary dynamo-electric
machine in circuit with an external source of electromotive-force, and automatically
shifting a controlling mechanism to vary the electromotive-force of the auxiliary
dynamo, in response to, and inversely with, slight fluctuations in the load of the
prime-mover, thereby adjusting the torque of the said dynamo so as to compensate
for such fluctuations, substantially as set forth.
2. The herein described method of regulating the load on a prime-mover and
the speed of its driven machinery, when the power or work is subject to
fluctuations, which method consists essentially in augmenting or opposing the
effort of the prime-mover, according to the requirements of the work, by the torque
of an auxiliary dynamo-electric machine in circuit with an external source of
electiomotive-force, and automatically shifting a controlling device in response to
such fluctuations, so as to vary the electromotive-force of the said dynamo in
compensation for changes in the load or power of the prime-mover and in the
electromotive-force of said external source, substantially in the manner described,
thereby regulating the speed of the connected machinery by adjusting the torque
of the auxiliary dynamo to maintain the requisite equilibrium betweeen the net
load on the prime-mover and its driving effort.
3. In an electric load-regulating apparatus, the combination, with a prime-motor
and its driven machinery, of a regulating dynamo operatively connected therewith,
and automatic controlling mechanisin adapted to increase the electromotive-force
of the said dynamo when the load on the prime-motor is diminished, and to
diminish its electromotive-force when the load is increased, whereby the electrical
work of the said dynamo is adjusted to compensate for fluctuations in the work of
the connected machinery, and the resultant load on the prime-motor is regulated,
substantially as set forth.
4. The combination of a prime-motor; the driven machinery constituting its
working load; a regulating dynamo connected therewith by power-transmitting
devices; a storage battery in circuit with the regulating dynamo; a compound
field-winding on the said dynamo adapted to vary its electromotive-force in
compensation for sudden and violent fluctuations in the working load, as described,
and automatic controlling mechanism' adapted to vary the electromotive-force of

page_text: the said dynamo independently of such field-winding, so as to compensate for
fluctuations in the counter-electromotive-force of the battery due to its variable
charge, whereby the rate of work of the said dynamo is adjusted, so as to regulate
the load on the prime-motor, substantially as set forth.
5. The combination of a prime-mover; the driven machinery constituting its
working load; a direct-current regulating dynamo adapted to operate inter-
changeably as a generator and as a motor; power-transmitting connections between
the prime-mover and the regulating dynamo, whereby the latter is enabled to
oppose or assist the prime-mover as may be required; a storage-battery in circuit
with the regulating dynamo, whereby energy is stored when the power exerted by
the prime-mover is in excess of the working load, and restored to the system when
the working load is excessive, as described; adjustable mechanism, such as a field
rheostat, for varying the power of the regulating dynamo; power-operated devices
for shifting the said adjustable mechanism; and automatic means, responsive to
slight changes of speed, controlling the application of power to the said mechanism,
whereby the rate of work of the regulating dynamo is adjusted so as to regulate
the load on the prime-mover and to maintain the normal speed of the connected
machinery, notwithstanding fluctuations in the work or source of power, substantially
as set forth.
6. In a load-regulating apparatus for a prime-mover, the combination, with the
prime-mover and its driven machinery; of a regulating dynamo-electric machine
operatively connected therewith and with an external source of electromotive--
force; a governing mechanism automatically responsive to changes in speed and:
adapted to vary the supply of working fluid to the prime-mover; and a second
automatic mechanism operative by a smaller degree of speed variation than the
first, and adapted to vary the rate of work of the regulating-dynamo, whereby
the operation of the first governing mechanism is limited, and the load and
speed of the prime-mover are simultaneously regulated, substantially in the manner
described.
7. In a load-regulating apparatus for a prime-mover, the combination, with a
prime-mover and its driven machinery; of a direct-current regulating dynamo,
coupled therewith by power-transmitting connections; a storage-battery in circuit
with said dynamo; adjustable mechanism, such as a field rheostat, for varying.
the power of the regulating dynamo; power-operated devices for shifting the said
adjustable mechanism; an automatic governing device controlling the application
of power to the said mechanism; a second governing mechanism adapted to vary
the supply of working fluid to the prime-mover; and automatic means of varying
the operating position of the second governing mechanism, (and thereby the supply
of working Huid to the prime-mover,) according to the state of the charge of the
storage-battery, substantially as set forth.
D Dated thin 4th day of Avant 1806
CARPMAEL & Co.,
Agents for the Applicants.