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Патент USA US2113436

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2,113,436
A. Jl WILLIAMS, JR
ÉEASURING SYSTEM'.
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IN'vENToR `
April 5, 1938.
2,113,436
A. J. WILLIAMS, JR
MEASURING SYSTEM
Filed July 25.,` 1934
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INVENTOR
Apri1z5, 1938.
'
A. J. WILLIAMS, JR
2,113,436
1
MEASURING SYSTEM
Filed July 25, 1934
_
5 Sheets-Sheet 3
INVENTORv
April 5, 1938.
A. J. WILLIAMS, JR
MEASURING SYSTEM
Filed July 25, 1934
2,113,436
`
5 Sheets-Sheet 4
INVENTOR
April 5, 1938.
A; J. w1|_|_|AMs,YJR
2,113,436
MEASURING SYSTEM
Filed July 25, 19:54
.5 Sheets-Sheet 5
~INVENTOR
l
Patented Apr. 5, 1938
2,113,436@ `
UNlrsD STATES PATENT lorifice
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2,113,436
MEASURI'NG SYSTEM
Albert J. Williams, Jr., Philadelphia, ra., assign#
or to Leeds & Northrop Company, Philadel
phia, Pa., a corporation of Pennsylvania
Application July 25, 1934, Serial No. 736,853
az claims. (Olmi-H3191@
Figs. 1a and 1b are detail views, in* side eleva
My invention relates to methods of and appa
ratus for determi-ning ¿the magnitude or changes
tion, of coil suspension systems;
`
shown in Fig. 1 in a network of the Wheatstone
tliermaL. mechanical, ',ïphysical, electrical, etc.,~
bridge type;
5 and more particularlyîto balanced networks or
circuits including a galvanometer, or other de
tector responsive to unbalance.
_
Fig. 2 illustrates a system using apparatus
in magnitude cfa measured condition, such as
5
Fig. 3 ‘schematically illustrates a system -in
which the galvanometer field system is movable;
,
' Figs. 4, 5 and 6_ rare front elevation, side ,eleva
In accordance with my invention. upon change
in magnitude of the measured condition, the
1D movement of the galvanometer coil, or equiva
lent, from a neutral control position initiates op
eration of a driving system for rebalancing ad
tion, and plan views, respectively, of apparatus
shown in Figs. 1 to 3 with parts omitted and parts 10
in section, for clarity;
'
l
,
-
Fig. 7 is a modiñcation in which the ñeld sys
tem and coil-suspension system are stationary; »
justment of the network, and diîxïg-'tlïé'ï’ebal
Figs. 7a and 7b illustrate alternatives of the
_ ancing operation, there is produced an effect,
0 whose magnitude is a function of the speed of
system of Fig. ‘7;
_
'
15
Fig. 8 shows use of the basic elements of Fig.
7 in a Wheatstone bridge network;
the driving system, which limits displacement of
the coil from neutral control position to small
Fig. 9 illustrates use of a multi-coll galvanom
- magnitudes and which jointly with the unbal
eter;
ance due to the change of the measured condi
Fig. 9a illustrates use of another multi-coil de- 20
20 tion produces deflections of the coil for regu
lating the speed of the driving system to obtain I'
Figs. 10 to 14 show further modiñcations of the
rebalance-in _a minimum of time without over
vice;
I
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‘ invention.
shooting.
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_
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.
_
Referring to Fig. 1, there is produced across
More particularly, in some forms of my inven
the terminals- I and 2 of the measuring network 25
25 tion, the elements cooperating with the coil for P, a voltage whose magnitude is determined by,
control of the motor speed are shifted by the i‘e- ~ or varies with, the magnitude of the particularl
balancing motor so that the neutral control po
condition under’ measurement; speciñcally, tlíe
sition is changed at _substantially the same speed » thermocouple T is a device responsive to the va~
as the coil position in responding to unbalance of
30 the network; in-those modifications of this type riations in temperature, or'radiant energy im- 30
pressed upon it, to produce between the terminals
' in which the ñeld magnet for the coil is also
I and 2 a correspondingly varying voltage which
shifted, as well as in other forms of my inven
is balanced by adjustment of the contact C along
' tion in which the neutral position and ñeld mag
the potentiometer slide wire S across whose ter
net is not moved, a small generator driven by the minals is connected a suitable source of current 3
rebalancing motor introduces into the galvanom
B.' So long as the system is in balance, there is
, eter circuit a voltage which is proportional to its
'
tion of the acceleration of the rebalancing oper
no current flowing through the coil G, and conse
quently there is no torque exerted tending to de'
ilect the còil. Upon change in the voltage across
the points I and 2, due to increase or decrease o_f ¿n
.the condition under measurement, current flows
ation.
In other forms of my invention, during the re
through the coil G, and the -resulting reaction
with the magnetic ñeld, produced by the ileld
speed; more specifically, in the last mentioned
forms, the introduced'voltage also preferably has
¿o a component whose magnitude is a direct func
balancing operation, there is introduced into the _ producing device F, which may be a permanent
magnet or a suitable electro-magnet. produces a 45
45 measuring or detector circuit a voltage whose
magnitude varies as a power of the speed of re
torque tending to rotate the coil in one direction ’ '
Y balancing higher than the ñrst power.
or the other depending upon the sense of the un
My invention further resides in thevmethods
and systems hereinafter described and claimed.
For an understanding of my invention and for
' an illustration of various forms thereof, refer
-ence is to be -had to the accompanying drawings,
in which:
balance.
'
As more clearly appears in Fig.v 1a, the coll
suspension system comprises the bracket 3, car- 50
rled by the supporting member I, and the sus
pension strips or springs 5. 5, which may be, as '
usual in galvanometer construction,Y thin ilat
.
` _ _-Fig. 1 schematically illustrates a potentiometer
u system utilizing the invention;
_
-
strips of gold, silver, or other metal; ores shown
lullig. 1b,the eoilmaybesuppcrtcdbytheplv- ß
2
_ 5
2,113,436
oted shaft 5a. Either type of suspension may be
used for the galvanometer coil of any of the sys
tems herein described. The strip suspension is
cell receives the beam of light to eil’ect energiza
tion of the other winding of the motor to provide
preferred as it avoids pivot friction.
one cell to the other, remaining for longer peri
ods cn the cell giving braking impulses as bal
ance is approached. The entire action, the re
sponse _to unbalance and rebalancing, is com
a braking impulse. The beam rapidly shifts from _
The support 4, Fig. la, as schematically illus
. Ätrated by gear 6 and dotted line ,'I, is adapted to
be swung in either direction by the motor 8 in ac
âcordance with the sense of deñection of the coil
En
pleted 'in> a veryv short interval of time, as one
second, even for maximum change of the meas
ured condition within the range of the instru-- 10
G. 'I'his may be effected by attaching a switch
lo, arm to the galvanometer coil G which will engage
_ Í one contact or the other of a reversing switch
A S when the needle deiiects from a position between .
ment.’
The system' shown in Fig. 2 is generally the
the contacts which are mounted on the support.
same as that of Fig. 1, ~except that the measuring
However, I prefer to use the arrangement shown network is of the Wheatstone bridge type instead
15 which comprises the photo-cells 9, 9a carried by _of the potentiometer type. Bricily, when the
the support 4, a source of light or lamp- I0, also bridge W is unbalanced because of change in the .
carried by the support, and a small mirror or re
condition, as temperature, measured by .the re
flector-II carried by the movable coil.
sponsive device TI, which in this_case is specifi
_ When the potentiometer circuit is balanced, the
20 ,beam of light reilected by the mirror II does not
impinge upon either photo-cell or equivalent de
vice, e. g. the coil is in a neutral control position;
when the galvanometer. deilects in one direction,
_ the beam is received by one cell 9 or 9a, and’upon
deilection of the coil in opposite direction, the
cally illustrated as a coil of material having a
substantial temperature coefiicient of resistance, 20
the galvanometer G deiiects in _one position or
the other from neutral control position, depend
ing upon the sense of unbalance of the bridge,
whereupon the motor 8 eiîects actuation of the
support 4 in such direction that the actuating
force, or torque, on the coil system produced by
beam is received by the other cell. By a relay~
arrangement'which is more specifically herein ' the change of the measured condition is reduced,
lafter described, when oneof the photo-cells re
and concurrently there is effected relative adjust-`
ceives the reilected beaxn,-one of the field wind
ings‘Fo of motor 8 is energized to drive the sup
ment of the contact C and slide wire S in proper
direction to rebalance the bridge. The system
port 4 in one direction, and when the other _ comes to balance with the coil displaced in space
photo-cell receives the beam, the other ñeld wind , from its original position but in the same neutral
ing FI' is energized to effect> movement of the control position with respect to the photo-cells,
support 4 in a reverse direction. _
or _alternative motor circuit-control elements. _
v The motor and its connections are such that
the slide-wire support can be accelerated at a
rate- preferably at least as great as the maximum
acceleration of the coil G.
'
ad
'
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In the arrangements described, because the 35
iield magnet of the galvanometer is iìxed in space.
for every diiferent magnitude of -the condition"
the coil G occupies a different position in the ,
The direction in which the support 4 is move
40 by the motor 8 is always such that the torque
magnetic field. For highly precise measurements
T is reduced;-that is, the support is moved in the
this is not desirable since it is practically irn 40
possible to produce a 'iield which'is absolutely
symmetrical; even minute particles of magnetic
same direction as the deflection of the coil.
dust are sufñciént to introduce error.
,due to change in voltage of the responsive device
`
'
concurrently with this torque-reducing move
Therefore, I prefer,- as shown in Fig. 3, to mount Y
ment of the support 4, the circuit is being rebal
the iield magnet F, or equivalent, upon- the _sup
_anced by adjustment of the contact C by opera-l port 4, so that for all positions o_f balance of the
tion of the moto'r 8. As appears in Fig. 1, the network, whatever may be the position of the »
slide wire S is adjusted concurrently with the coil G in space, it will have the same position rela
movement ‘of the support 4, the relative move
tive to the field magnet. With this arrangement
ment between the contact C and slide wire S as thus far described, since the ñeld magnet tends :
being in the proper~` sense to restore balance of to follow the coil, there is a substantial reduction
the network. Accordingly, in the arrangement or elimination of the generator' action' which in
- described, after the coil G defiects in`__response to the system of Fig. 1 tends to oppose. the deflec
unbalance of the network it does not return to tion of the galvanometer coil G in response to
its previous position when the network is rebal
the unbalance of the network, and which there
anced but remains in _its new position.
fore gives desirable damping to the coil move
¿~ The pointer or marker I, which may be generi
cally termed “controlled structure" of the meas- ,
ment.
_
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"
.
In the system of Fig. 3, the point 2 may be
directly connected to the terminal I4 of the slide
ì uring system, is coupled to the movable support,
«j i or to _the slide wire, for movement in unls`6n there - wire~ by a conductor of low or negligible resist
,"with so that its position with respect to the scale ance, but with such connection, due to the small
I2, or to the recorder sheet I3 driven by the con
or negligible counter E. M. F. induced in the
A _ stant speed motor I3a, is uniquely determinedI
coil G, there will be a tendency for the system
_ _by the magnitude of the voltage produced by the „_ to hunt or overshoot the position of balance. To
65 lresponsive device T. Specifically the` cord 29 for overcome this, there is produced a torque acting 65
4,moving the element I passes over the driving pul
on the coil system counter to the torque resulting
jley 28 which rotates with support 4, as shown in from the changeof the measured condition, which
counter-torque is a function of the speed of _re
balancing; more specifically, there is introduced
70 ducing a high torque so that the support 4 will into the network P, during rebalance, a voltage
very closely follow the pointer in its deñecting which is inopposition to the unbalanced voltage.' 70'
movement. When~ the support overtakes the gal
and whose magnitude is a directiunction of the
vanometer coil moving toward its ñnal position, speed of rebalancing. As shown, this can be con
the motor is deenerglzed, and when thesupport` veniently effected by mechanically' connecting a
`Fig. 1a.
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The motor 8 is preferably one capable of pro
75 4 passes the neutral position, the other photo
Asmall.generator I5 to the motor 8 to' produce at
_
2,113,436
' the generator terminals' a voltage which is pro
,
3
no anode current iiows in either of tubes V, VI,
portional to the speed of the motor 8. The cur
rent through the resistance R, and therefore the
when neither of the photo-cells receives light
from source I0.
'I‘here is no flow of anode cur
voltage drop produced thereby across the termi
rent because the grid and anode voltages are
nais of the resistance, is proportional to the speed ._,out of phase with the re'sult that when each of support 4. 4The introduction of this voltage into lanode is in turn positive, the voltage of the asso
-the network produces a damping torque substan
ciated grid is below the critical voltage and the
tially eliminating the tendency for the system anode-cathode path within the tube is of ex
to overshoot the point of- balance while permitting tremely high resistance. When, however, either
lrapid rebalancing, e. g. by design or adjustment, of the photo-cells receives light, the grid of the 10
the system may be given a critically damped char
acteristic affording a minimum time for rebal
ancíng for any lextent. of unbalance without over.
‘ corresponding tube becomes positive while its
plate. is positive, allowing full plate current to
flow through the corresponding motor winding
F0 or FI for each -positive half wave to apply
It is characteristic of thè operation of the sys, either driving impulses or braking impulses de 15
tem that n__o matter'how great. the torque due to _ pending upon immediately priorvconditions of op
change of the measured condition, the angle of eration. .
l
deflection of _coil G with respect .to the median
This control system has theA advantage `that
line> between the photo-cells is always small or full torq'ue is applied to the motor for _the slight
est deñection _of the coil G; coil G is not required 20
Figs. 4.,“'5 and 6 illustrate details of construc
to perform any work in actuating switch con
tion of'a high- spe'ed recording and indicating tacts; the use of contacts involving inertia, spark-.
mechanism s_uitableffor usein the systems thus ing', variable contact resistance, is avoided, etc.
far described. Upo'n the support 4 is mounted However, my invention is not limited to use of
shooting.'-
zero.
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y
f;
_
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a bracket fòr- the’alamp-_iil from whichl light
passes through the s‘lot 22 in the member 23 to
the mirror ii which reflects the beam, when the
this type of control system.
wire."
~
^
25
In the several modifications already described,
the galvanometer coil has no fixed neutral posi
coil G is in deñected position,'on to one or the> tion in space,- but has a different neutral position
other of the mirrors 24> within the photo-cell ' for every different position of balance of the slide
housing 25 depending upon the sense of the de
30
flection. The photo-cells- 9, 9a. respectively; are
In- the system shown in Fig. 7, the galvanom
preferably at the focal points of the mirrors.
eter ñeld magnet, the galvanometer support; and
` The galvanometer coil G is held by its suspen
the photo~cells, or equivalent control means,
-` sions 5, Sabetween the pole pieces 26, 26a. When remain stationary and the ~neutral position _of the
35 the practice of the modiilcation shown in Fig. 3
galvanometer coil is fixed in space. .As in the
is to be followed, the 1field magnet F,-Fig. 1, .is other modifications, deflection of coil G in re
attached to and moves with‘these pole pieces, for sponse to change of the measured condition ef
movement with the support 4. As more clearly fects rotation of motor "8 in onedirection or the
shown in Fig. 4, the support 4 is rotatable with other to adjust slide-wire S or equivalent to re-`
the shaft la which is driven from gear 6 of motor balance -the-measuring network. ¿To effect ref.
8. Upon thebsame shaft is mounted the disk 21 lbalancing in‘a minimum of time without over
which carries the slide wire S for movement with shoot, there is utilized an arrangement including
-respect to a fixed contact C. Upon the shaft 'la the direct-current generator 'I5 driven by motor
is also mounted the` pulley 28 whichthrough the 8. The transformer l1 having its primary I6 in
cord 29, or equivalent, 4ei’fectslmovement of the the generator circuit and its secondary in the '„
indicator of pointer I.
~
measuring -circuit. introduces into the galvanom
When the practice of the modification of Fig. eter _circuit a voltage proportional tothe acceler
lis to be followed the’con'struction may be the ation of the motor; otherwise expressed, the
same, except that the magnet F is secured to a voltage introduced into the primary network by
50 back board 30 which is held stationary.
^ transformer I] is an infinitesimal calculus func
As clearly shown in Fig. 5„it is desirable that’ tion of the rate of rebalancing of the measuring
the axis of rotation of the supporti be concentric network. Ignoring for the moment other torques
with the axis of deflection of the galvanometer on the coil system. the acceleration of'the gal- ‘
vanometer is therefore, at all times proportional
'A preferred control system for the- motor 8 is to the acceleration of the motor I5, and in start
shown in Figs. 1, 3 ,and subsequent ñgures. One ingfrom rest, both _the coil and motor i5 move
terminal of a source of alternating current, as a as if geared together. With no other torque
commercial power or light line,\ is connected to on the galvanometer, this control keeps the'av
the _tapped winding TH which supplies current erage acceleration of the motor zero. For any
coil
G..
,
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for heating the cathodes C0, Ci of the two tubes ' other torque applied to the galvanometer, _the il()
V, VI, preferably grid controlled rectifying tubes,
such as “thyratrons." The other terminal of the
source is connectedto one amature terminal of
the motor 8. 'I‘he field windings F0, Fl are con
-nected between-the other armature> terminal of
, motor 8 ,and the anodes a, ai, of the two thyra#
trons whose grids g, `g|, are connected' respec’
tively to the cathodes of_ the photo-cells 9, .9a.
'I'he'anodes of the photo-cells are connected to .
a suitable point afforded, for example, by the volt-f
age dividing impedances DI, DIa. The winding
BV, which may be a coil of an autotransformer
including coils DI, DIa and TH, through the ccnl
- densers Po, PI , applies to the grids g, gi ,an alter
nating voltage of such magnitude and phase that l
control system above described applies .a propor»
tional acceleration tothe motor; therefore, the
greater the applied torque, the greater the coun
ter-torque due to the generator I5 and trans
former i1." Of these other torques, the one due
to the unbalance in voltage between the thermo- -
couple '_I' and' the slide-wire S is the one of most,
importance.
.
.
As thus far described, the slide-wire would tend
to oscillate about the position of'rebalance like
an undamped galvanome'ter about its zero; the
inertia involved is that of the-motor armature `
and'moving parts-driven thereby, and the stiñ'
ness factor is the relation between accelera or.
(net torque) applied to’ the motor and -imbalance
4.
'
2,113,436
I of the slide-wire expressed as the angular rela
the voltage drop due to this second component
tion of the motor shaft, e. g. the angle through
which the shaft should rotate to effect balance.
To prevent this oscillation, damping is effected
`by applying a counter-torque to the galvanometer
which is proportional to the speed of motor 8.
Specifically, the resistance R in the circuit of
generator l5 is included in the galvanometer cir
erator current is that determined by the direct
current resistance in the coil, and is therefore
constant. Practically, however, this condition
does not exist during condition of operation as
, cuit to introduce a Voltage proportional to the
ordinarily the motor speed is always increasing
will be enhanced. So long as the speed of the
generator remains constant the only voltage
across the terminals of the coil due to the gen
or decreasing. The voltage across R due to the
iiow of the generator current is continuously pro
acceleration (component) proportional to its own portional to the speed of the generator and there
fore the speed of rebalancing.
speed, which is the desired damping effect. I
The system shown in Fig. '7b is also suitable
Assuming that the 'system is balanced, e. g.
that the thermocouple voltage equals the effec- > for introducing into the network a voltage pro
tive slide-wire voltage, and the motor 8 is at rest, portional to speed and acceleration of the coil
10 speed of motor 8. VThe net effect is a modification
of the control of motor 8 so that it has an added
_and that the thermocouple voltage abruptly
changes to a new value. the slide-wire will rapidly
move toits new position of balance in accordance
'20 with the same law asl the needle of a critically
suspension support during the rebalancing oper
ation, The more rapid the change of current,
the less the reactance offered by the condenser
|8a; consequently, more current from the gen- .
damped galvanometer if connected across the
thermocouple, would follow in moving to a new
erator l5 passes through the resistance R to in
crease the voltage drop across the terminals o
deiiection; e. g. this system, as well as others dis
this resistance.
closed, involving a null method of measurement.
with all its advantages, procures a measurement
When a Wheatstone bridge or like network is
used with this modification or that of Fig. 3 in
`
_»
which the ñeld magnet follows the deflection of
Contrasted with other high-speed recorders the coil, the voltage produced by the generator I5,
using balanced networks, my systems have a ‘ or equivalent is introduced into the arm of the
bridge which includes the galvanometer coil, as
small dead range or great per cent sensitivity;
~ 220 with my arrangements can-be used a galvanom-l „ shown in Fig. 8.v Though I have illustrated the
eter of such high sensitivity that a very minute particular arrangement shown in Fig. 7, which
unbalance will cause sufficient deflection to start ~ utilizes a series arrangement of resistance and
rebalance, whereas of other recorders it is gen
mutual inductance, either of the other arrangements of Figs. 7a or 7b may be used.
erally true that the sensitivity cannot be in
creased beyond a certain point for then the gal
. It is not essential' that the counter-torques
vanometer, for» large unbalances, goes off scale, result from introduction of an electromotive force
its coil and suspension system being subjected to into the galvanometer circuit. As shown in Fig.
the shock of engagement with stops, etc. In my ' 9, the coil system of the galvanometer may com
prise two coils movable as a unit but electrically
arrangements, no matter how large the unbal
separate. One-of them, Ga, is traversed by the
40 ance, the angle of deiiection of the galvanometer
coil is always small since the counter-turques. unbalance current of the measuring network _N,
immediately applied and eiïective during rebal
.and the other Gb receives current from the' gen
= ancing, keep the galvanometer coil at or near
erator l5. As in the other modifications motor
zero at all times, e'. g. the net torque acting on 8, or other driving system, is responsive to de
l4.5 the galvanometer coil is always small.. The ratio -i‘lection of the coil system to actuate the slide
of the length of the. recorder chart, or length of _ wire and generator l5 for rebalancing in a mini
the slide-wire, to the smallest distance through> mum time without overshooting. The measuring
which the’coil must deñect to initiate rebalance network specifically shown in Fig. 9 is a Wheat
' (the per cent sensitivity) can be made practically vstone bridge circuit for making conductivity
as high as desired; for example, the chart may be I measurements. The conductivity cell T3 is in
.ten inches long and yet the system will respond ~ one arm of the bridge which, as shown, is .pref
to a change in magnitude corresponding to as erably supplied from an alternating current
source which also supplies the ñeld coil GF -of
little as .025 inch on the chart. In my systems,
the extent of movement of the slide-wire'is not . coil Ga. Coil Gb has its own field', for example,
proportional to the deñection of thegalvanometer. a permanent magnet, or a field coil energized by
coil occurring upon change of the measured con
dition, but is proportional to the torque which , . Referring to Fig. 9a, the coil Ga is'of a deñec
the unbelance produces on the galvanometer coil. tion instrument. One end of the spring 5c which
Figs. 7a and 7b show alternative methods` of >opposes the torque eiîecting defiection _of coil Ga
introducing into the galvanometer vnetwork a is fast to the coil shaft 5d and the other end of
counter voltage having components proportional. the spring is secured to an abutment 3a, adjust
to speed and acceleration or whose magnitude is ' able by the motor 8, or other driving system, con
dependent upon diiîerent functions of the rate trolled by the contacts- llc, 9c, or other circuit
of rebalancing of the primary or measuring net- controlling arrangement. Upon change in the
as rapidly as a deflection instrument.
direct current.
65
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60
work. Referring to‘ Fig. 7a’. the voltage drop
current through Ga. the coil deilects in one direc- '
across >the inductance I8', due to the current > tionor the other depending upon the sense of
from the generator, will have as one component
a voltage due to the direct current resistance lof
the winding, which is proportional to the speed
70 of the generator, and another component which
is dependent upon the rate of change of speed
of the generator. Upon rapid increase, for ex
ample, of the generator current, the coil will oiîer
an impedance which is the greater the greater
75 the rate of increase of the current; consequently,`
the‘current change whereupon the driving sys
tem changes the position of abutment 3a until
the torque of spring 5c again balances the elec
trical torque, concurrently changing the posi- -
tion of controlled structure, as indicator Ia,
and/or a recorder pen, etc.
The magneto l5
driven during the rebalancing adjustment by the
driving system produces in the coil Gb, movable
with coil Ga, a torque of magnitude determined 75
2,118,439
by the speed of rebalancing and in opposition to
the 'electrical torque of coil Ga, to eil’ect rebalnnc-A
ing in minimum of time without overshoot. _In
addition, a torque proportional to acceleration
may be produced in Gb by any one of the various
expedients shown in Figs. 7, '1a or 7b.
It is not- necessary, however. to provide `sepa
ratecolls .when the measuring circuit uses al
ternating current for as shown in Fig. 10, both
-10 direct current from generator -IE» and alternating
f..
5
toward the new position of balance. Concur
rently, the piston HP having a small aperture 0.
or other leak, is moved to the right, the difference
in-pressure on opposite sides of the piston being
proportional to the square of the speed of the
movement of the piston relative to the Ahousing
or cylinder H, vwhich is connected to the slide
wire contact C. The pressure diiferential effect
ing movement of the housing is opposed by the
spring SP. As a result, the displacement of con l0,
tact C in space from its neutral position dur
ing rebalancing is a function of the square of
current from the unbalanced network may
'traverse one rand the vsaine coil G. The par
ticular network shown is a frequency-responsive
bridge such as more specifically described and
the speed of rebalancing. The control system
claimed> in IWunsch Patent 1,751,538. A-change
in frequency of the current supplied by the source
the condition until the network is balanced and
contact Chas returned to its neutral position.
connected to terminals i, 2 of the network pro
duces a diil’erencef-in voltage between the con
tacts C, Ci of the Aslide-wires S, Si which is im
system uses contacts actuated mechanically by
the galvanometer instead of an optical system.
-pressed through balanced bridge G, G', G', G'
'I‘he use of butt contacts is not always possible 20
does not come to rest at the new magnitude of
1.5
. As noted above, the control for the driving
due to the limited torque available; when they '
upon the galvanometer coil G which is in one arm
of the bridge. »Alternating current is supplied to ' are used in this or- any of the other modìiications,
the field coil F9’ of the galvanorneter through the
they prevent the coil,~ or equivalent, from mov
transformer FT.
ing far from its neutral position and so afford
rapid response of the driving system, under which
»if
i.
_
‘
25 ¿ Deflection of the coil effects energization of
motor 8 in proper _direction to adjust the slide l circumstance the introduction of a torque which
wires S, Si for rebalanceíof the network. Direct is a function of acceleration may be omitted. In
~current from the generator i5 'which is driven by general, in cases where the detector has a slow
motor 8 is ~also impressed upon coil G, through the speed of response, itis more desirable that a
torque proportional to acceleration b'e e intro
network G, G', G', G', which introduces a volt
age component which is a direct function of the duced into the rebala'ncing than in systems us
slide-wire speed. The-battery BG supplies the, ing a detector with a high speed of response.
direct current component of the galvanometer
-The modification shown in Fig. 12 is similar
to that of Fig. l1 in that during the rebalancing
~-field for. reactionwith the direct current com
there is introducedinto the galvanometerfcir 35
35 ponent. of the coil current to produce'a counter
torque having the same purpose'and following cuit. a voltage proportional to thesquare of the
speed of rebalancing in opposition to the unbal
» the same law of variation as inl the prior modiñca
tions.' '
40
anced voltage due to change of .the measured con
'
In the system shown in Fig. 1l, the slide-wire
device SA may be, for example, an attenuator
dition? The ñyball F, or equivalent centrifugal
voltage. 'I'he voltage En: to be measured is ap
device driven by motor 8, is mechanically con 40
nected to the contact C2, whose position, there
fore, is proportional to the square of the speed of
plied to the terminals I, 2, the resistance between
rebalancin'g. The reversely poled voltage-divid
network giving logarithmic variation of output
ing or potentiometer resistances R3, vFM are selec'
tiveiy connected through switch 40 in circuit with
_ the constant voltage of B is balanced. The de
the galvanometer.l The switch 4I! is operated as
_tector system responsive _to unbalance may in
clude a contact-controlling galvanometer, as in
by slip- clutch Il so that when motor 8 is ener-dicated; or it may include an optical system as in _gized in one direction, resistance R3 is con
prior modiñcations; or it may be of the chopper
nected in circuit, and when energized in reverse
ampliñer type „disclosed and claimed in my co-_ -direction resistance R4 is connected _in circuit. 50
which is constant, and contact C is adjusted until
'pending application Serial No.l634,425 ñled Sep
tember 22, .1932, which can also be used with the
systems of Figs. 12 to 14.
_
The centrifugal device by >adiustrnent of contact
C2 therefore provides for voltages proportional'
to the square Aof the speed of rebaiancing and
. The driving system for effecting the'rebalance switch 40 selects the one of proper 'polarity'.
During rebalancing, the galvanometer coil sys 55
. may-be a reversible motor, as in the prior modifi
cations, or it may, as shown, comprise a selectivel ' tem is, therefore, subject to a torque varying as
clutch device SC. When> the network N is un
balanced in one direction, coil fi eñects driving
.engagement between driven gear 6c 'and driving
the square ofV the speed of rebalancing ~and the
control of motor 8 is accordingly modified.
A somewhat simpler arrangement for obtain
gear 6a, and for opposite sense of unbalance of ing the same result and using the same method 60
the network gear 6c is moved by coll fo into enf is sh wn in Fig. 13. In this modification, _the
gagemeht with the other Idriving'gear 6b for .excit tion forA the field i5! of generator i5 is
movement in opposite direction. The driving supplied by a second generator IIB also driven
motor 8a is constantly rotating in one direction. by motor 8 -so that the output voltage of generator
This type of driving system may be substituted I5 varies as the square of the speed of rebaianc 05
for the reversible motor of other modifications.
To obtain proper polarity of the voltage of
' 'I‘he motion ofl gear 6c is transmitted to gear generator I5 for both directions of rotation, the
1c by a belt 1b. or equivalent friction device. per
current in its field is cause'd to flow always in‘the
mitting slip. Other limited torque transmission same direction. This is conveniently effected by
arrangements may alternatively be used between connecting a bridge rectifier BR. between the field 70
iBf and the output terminais oi' generator lli.
motoria and gear 1c.
„
`
~
'
'
_. Assuming that the impressed voltage Ex de
The rectiñer elements are .preferably ofthe solid
type. using copper copper-oxide plates. `
creases the driving system responding to the de
tector G rotates‘gear 'ic in such direction that thel \» The system of Fig. 14 .also provides for intro
netvirork- durin? the
75 support for the attenuator SA moves to the left duction, into the
6 1
2,113,436
rebalancing, of a voltage whose magnitude varies ’ ing system, producingV4 an eiîect substantially pro
as a power higher than the ñrst power of the portional to the acceleration of said driving sys
speed of rebalancing. The output circuit of the tem, and controlling the position of said member
magneto or generator I 5 driven during the rebal
ancing operation includes a resistance TR. and `a
resistance CR having the characteristic of exhib
by said effects and the imbalance jointly for reg
ulating the speed of the driving system.
4. In a system unbalanced by change in mag
nitude of a condition under measurement, in
cluding a member deñecting in response to the
unbalance, and a motor responsive to deflection of
said member from neutral position to eñect re 10~
balancing adjustment of an element of said sys
tem, the method which comprises during the re
balancing adjustment producing an effect sub
stantially proportional tot the speed of said ele
iting lesser resistance at higher current densities;
for example, as shown CR may comprise oppo
sitely poled solid rectiñers, of the copper copper
10 oxide type for example, whose forward resistance
decreases the higher the forward current, the
variation following a law higher than the ñrst
power, or it may comprise anuntreated carbon
ñlament lamp which has a generally similar cur
15 rent-resistance characteristic. In both cases, the
ment, and controlling the position of saidxmem 15
higher the speed of rebalancing, the greater the
ber by the unbalancev and said effect jointly for
' proportion of the voltage generated by magneto
l5 is developed between the points z, :c for intro
regulating the speed of the motor. '
5. In an electrical network unbalanced by
change in magnitude of a condition under meas'
urement including a- member, deflecting in re 20
sponse to the unbalance, for controlling a driving
duction into the measuring circuit.
20
A like result may be obtained by using an ordi
4nary resistance at CR. and a metallic iilament
. lamp, as a tungsten lamp, at TR, since the re
system which eiïeots rebalancing adjustment of ~
sistance of such a lamp increases with increase of the'network, the method which comprises pro-'
current. «Again, the higher the speed of rebal- ~ ducing a voltage whose magnitude is substantially
ance the higher the voltage generated by the mag
proportional to the speed of said driving system, 25
neto, and the greater the proportion of total gen
and introducing said voltage into the network to
erated voltage developed across the points œ, m, control the deflection of said member jointly in
thereby to obtain rapid unbalancingwithout over
accordance with the extent of unbalance and the
shooting.
>
speed of rebalancing for regulation of the speed
-
The law of variation of the generated voltage
of said driving system. '
between points œ, :z: may be made to follow a still
higher power law Aby 'utilizing a carbon lamp
si
'
30
6. In an electrical network -~ unbalanced by
change in magnitude of a condition under meas
urement including a member, deñecting in re-_»
resistance or copper oxide rectiñers at CR and
a tungsten or other metallic filament lamp re
sponse to the unbalance, for controlling a driving '
sistance at TR.
system which eiîects rebalancing adjustment of 35
'
While I‘have described `and explained varioust the network, the method which comprises pro
ducing a voltage whose magnitude is substantially
systems, it is to be understood that my invention
.is not limited thereto but is co-extensive in scope
with the _appended claims.
What I claim is:
-
proportional to the rate of change of the speed >
of said driving system, and introducing said
.
voltage into the network to control thedcñec 40
tion of said member jointly `in accordance with
_
1. In a system unbalanced by change in magni
tude of acondition under'measurement, includ
the extent of unbala?ce and the rate of change
of -the -speed of rebalancing for regulation of
the speed of said driving system.
'7. In ’an electrical network unbalanced by 45
ing a member deiieoting in response to the un
balance, and a driving system responsive to de
45 tlection of said member from neutral position t'o
effect rebalancing'adjustment of an element of
change in magnitude of a condition under meas
said system, the method which" comprises during
the rebalancing adjustment producing an eñect
urement including a member, deilecting in re- l
sponse to the unbalance, for -controlling a driv
whose magnitude is a direct function of the speed
ing system which effects rebalancing adjustment
of said element, and controllingl the position oi
said member from neutral position by the un
balance and said effect jointly for regulating the
of the network, the method which comprises pro- -
ducing a _voltage whose magnitude is substan
tially proportional to the 'speed of said driving
system, producing a voltage whose magnitude is
substantially proportional to the acceleration oi
` speed of said driving system.'
2. In a system unbalanced by change in magni
said driving system, and introducing said voltages ~
into the network to control the deflection of
said member jointly. in accordance with the extent
of unbalance and the speed and the rate of
tude of a, condition under measurement, includ
ing a in mber deilecting in response to the unbal
ance, and a driving system responsive to deñec
tion of said member from neutral position to ef
~i'ect rebalancing adjustment of an element of
'60" said system, the method which comprises during
change of speed of rebalancingfor regulation
- the rebalancing adjustment producing an effect _
substantially proportional t'o the rate of change
of the speed of said element, and controlling the
position of said member by the unbalance and
said effect jointly for regulating the speed of the
driving system.
’
r
of the speed of said driving system.
60
8. In a system including a member deiiecting
in response to a torque resulting from a change
in magnitude of a measured condition, and a
driving system responsive to deñection of said
member from neutral position to effect an ad
' justment of an element of said system for causing
3. In a system unbalanced by change in mag ‘ said member to move toward neutral control po
sition, the method which comprises, during said
. -nitude of a condition under measurement, in
adjustment, producing an eiïect whose magni
_ cluding a member deiiecting in response to the un
tude is a direct function of the speed o1- said 70
balance, and a driving _system- responsive’ to deflec
v tion of said member from neutral position to effect driving system, and controlling the' position of
said member from neutral position by said torque
rebalancing adjustment of an element of said sys
tem, the method which comprises during the re-` and ‘said effect jointly to vary thespeed of ad
balancing adjustment producing an eilîect sub- « justment of said, element as a function of said
torque _and said effect.’ - ~
_ ' stantially proportional to the speed of said driv
75
2,113,436 _
'
7
in response to a torque resulting from a change
in magnitude of a measured condition, and a
function of the speed of said driving system and
which jointly with said iirst torque controls the
position of said member for regulation of the
driving system responsive to deflection of said
speed of said driving system. `
member from neutral position to effect an ad
justment of an element of said system for causing
said member to move toward neutral control
change in magnitude of a measured condition, a
member deflecting from neutral position in re
` ' A9. In a system including a member deilecting
14. An electrical network unbalanced upon
position, the method which comprises, during
said adjustment, producing an effect of magni
10 tude substantially proportional to the speed of
sponse to application of atorque produced by
unbalance of the network, an impedance ad»
said motor, utilizing said effect to produce -a
justable to rebalance said network, a driving 10
systemresponsive to deflection of said member
counter-torque» oi proportional magnitude upon
from neutral position, and means for producing
said member,._ said torque and counter-torque »on said member a torque which is a direct
jointly determining the position of said member,
15 and varying the speed of adjustment of said ele
ment in_accordance with the position of said
member.
_.
-
`
10. In a system including a member defiecting'
»in response to a torque resulting .from a change
function of the speed of said driving system and
which jointly with said unbalance torque controls
the position of said member for regulating the
rate of adjustment of said impedance by said
driving system.
.
15. An electrical network unbalanced upon
change in magnitude of a measured condition, _a
driving system responsive to deilection of said member deiiecting from neutral position in re
memberg'from neutral position to eil'ect an ad sponse to application of a torque produced by
Y justment of an element of said system for causing unbalance of the network, an impedance adjust
able to rebalance said network, a driving system
said member _to move toward neutral control po
20 in magnitude of'a measured'condition, and a
sition, the method E_which comprises, during said
adjustment] producing an effect of magnitude
responsive> to deflection of said member from __
neutral position, and means including means op
erated by said driving system for introducing
said driving system, and utilizing said effect vto into said network a voltage of magnitude varying
produce a counter-torque of proportional mag _ as direct function " of the speed of said driving
system.
.
»
nitude
upon said member, -said torque and coun
80
16. A s'ystem comprising a member deilecting
ter-torque jointly determining the position. of
said member for regulation of the speed of ad-4 from neutral position in response to application
of a torque resulting from change in magnitude
justment of said element.
`
substantiallypropo?tional to the acceleration of
11. In a system including a member deiiecting ' oi' a measured condition, means adjustable to
movement of said member to neutral posi
35 in response to a torque resulting from a change effect
in magnitude of a measured condition, and a tion, a driving system ~responsive to deflection of
.driving system responsive to deñection -of said
said, member from neutral position for adjusting
member from neutral position to effect an' ad
said means, means including means operated by
justment of an element of said system for caus
40 -ing said member to move toward neutral control
position, the method which comprises, during said
adjustment, producing an eiîect of magnitude
substantially proportional to the second power of
the speed of said driving system, and utilizing
. said driving system to produce a current .of mag
'nitude substantially proportional to the speed of 40
said driving system, and means _for applying to
said _member a torque of magnitude substantially
proportional to the rate of change of said current.
17. An electrical network unbalanced upon
change in magnitude' of a measured condition, a
member deilecting from neutral position in re
- torque and counter-torque jointly determining* sponse to -application of a torqueproduced by un
the position of said member for regulation of the balance of the network, an impedance adjustable
to rebalance said network, a driving system re
speed of_-adjustment of said element.
12. In a system including a member defiecting sponsive to- deflection of said member from
50- in response to a torque resulting from a 'change -neutral position, means including means operated
Lsaid effect to produce a counter-torque of -pro
portional »magnitude upon said member, said
in magnitude of a measured condition, and a driv
by said driving system to produce a current of
ing system responsive to deflection of said mem- - magnitude substantially proportional _to the speed
ber from neutral position to effect an adjustment of said driving system. and means for deriving`
of an- element of said system for causing said from said current and introducing into'said net
55
member to move toward neutral control position, . work a voltage having a component proportional
the method which,A comprises, during said adjust
ment, producing aneffect of .magnitude substan
tially proportional to the speed of said driving>
to the speed of said driving system and a com
ponent proportional to the acceleration of said
. driving system. _
18, An _electrical network unbalanced upon
60 system, producing an veffect of magnitude `sub- _
-stantially proportional ~to the acceleration of said ' change in magnitude of a measured condition, a
driving system. and utilizing said effects to pro
' duce counter-tongues _upon ‘said member, said.
member deflecting from neutral position in re
sponse to application of a -torque produced by «
torque and said counter-torques jointly determin- ' -unbalance of the network, an impedance ad
.
justableto rebalance said network, a driving
system responsive to deflection of said member
13. A system comprising a member deñecting .from neutral position, and means including
ircm neutral position in- response to application ’ means operated by said driving system for in
65 ing the position of said member for regulation of _
the speed of adjustment of said element.- .
of a torque resulting from change in magnitude
of a measured condition.‘means adjustable to
effect movement ofA said member to neutral posi
tion, .a driving system responsive to deñection of
said member from neutral position for adjusting
75
said means, and means for producing on said
member a torqlie of magnitude which is a direct
troducing into said network a voltage substan
tially proportional to thesecond power of the 70
speed of said .driving system.
_
19. A system comprising a member deflecting
from neutral position in response- to changes in
magnitude of a measured condition, photo-electric
cells selectively'energized for opposite deflections4
8
_
2,113,436
of said member from neutral position,- la pair of ‘ for moving said member to a predetermined point
grid-controlled rectiñers Yha'ving said photo i under the control oi’ said amplifier, and means in
electric cells in their respective grid circuits, a cluding a magneto generator driven by said motor
reversible motor having windings connected re
and serving to reduce the current through said
spectively in the anode circuits of said rectiñers, galvanometer to zero as said member approaches
a source oi' alternating current for supplying said said predetermined point whereby the decelera 5
rectiiiers and photo-electric cells, a direct-current ltion of said motor is- completed when said prede
generator driven by said motor for producing a
current of magnitude which is a direct function of
the speed of said motor, and means for applying
to said> member a torque proportional to said
_ current to control the actuation _of said photo
electric cells.
20. In a system including meansior producingl
a standard electrical eiîect, means for producing
an opposing- electrical effect of magnitude deter
mined by the magnitude of a condition under
measurement, a detector energized in accordance'
with the resultant of said effect-s, and a driving
means controlled by the detector to effect bal
ance oi said effects by adjustment of an ele
` ment of said system, the method which com
prises producing, during the balancing adjust
ment, an eiîect varying as a power higher than
l5 Cl the ñrst power of the speed of said driving means,
termined point is reached.
'
>
»
25. In a device of the class described,_ a de
tector comprising an electrical network having a l0.
condition-responsive element and a galvanometer
~ connected therein, an ampliñer including two low
inertia- relays controlled by said galvanometer,
a movable member, a motor for moving said mem
ber to a predetermined point under the control 15
of said amplifier, and means cooperating with
said motor to reduce the current through said
element to zero as said member approaches said
predetermined point whereby the deceleration
of said .motor is completed when said predeter
mined point is reached.
‘
’
26. In a device of the class described,- a de
tector comprising an electrical 4network having
a thermo-responsive element and a galvanometer‘
and controlling the energization of the detector
by said last eiïect and said resultant eiïect jointly
for regulation of the speed of~ said driving' means.
connected therein, said network being normally
electrically balanced, said element being _respon-v
sive to a changing condition for disturbing the
ducing an opposing electrical effect of magnitude
determined by the magnitude of a condition under
said galvanometer, a movable member, a motor 30
for progressively moving said member underthe
21. In a system including means for produc- ,_ electrical balance of said network, an ampliñe'r
30 ing a standard~ electrical effect, means for pro- _ including two low inertia relays controlled by
measurement, a detector energized in accordance
v
~with the resultant of said effects, and a driving
means controlled by the detector to effect bal
ance of said eiïects by adjustment of an ele
ment of said system, the method which comprises
producing, during the balancing adjustment, an
effect substantially proportional to the square
of the speed of said driving means, and control
control of said amplifier to a predetermined point
as indicated by the lack of balance of said net
work, and anticipating means responsive' to the
action and direction of action oi said movable
member for -decelerating said motor.
-
27. In a device of the class described,‘a n`or- ‘
mally balanced primary network including an
_ elementresponsive to changing conditions to un
ling the energization of the detector by said _last balance said network and deñectable means hav
.ing an active and an inactivev condition, said
eiîect and said resultant effect jointly for regu
lmeans being responsive to the lack of balance
lation of the speed of said driving means.
22. A system comprising means for producing of said primary network to establish its» active
- ' a standard electrical eiîect, means for producing
condition, a _ member movable to restore the
an electrical effect of magnitude determined by ~ balance of said network and thereby -cause said
the magnitude of a condition under measurement,
- a network in which'said eiîects are brought into
opposition, a detector energized by unbalance of
_ said network, an impedance in said network ad
justable to rebalance it, adriving system con
trolled by said detector for eñecting adjustment .
of said impedance, and means for introducing
into said' network an electrical effect substan
tially proportional to a power- higher than the
first power of the speed of said driving system.
A
23. A system comprising means for producing
a standard electrical effect, means for producing
an electrical eii'e'ct 'of magnitude determined by
e the magnitude of a condition under measurement,
a network in which said effects are brought into
opposition, a detector energized by unbalance of
said network, an impedance in- said network ad
justable to rebalance it, a driving system con
trolled by said detector for effecting adjustment
of said impedance, and means for introducing
into said network an electrical effect substantial-_
ly proportional to the square of the speed of said
driving system.
^
24. In a device of the-class described, a` de
.tector comprising an electrical network havinga condition-responsive element and a galvanom
eter connected therein, an ampliñer including
two low inertia relays respectively controlled by
75 said galvanometer, a movable member, a motor
l
means to return to its inactive condition, af
motor controlled 4by said4 means in its active
condition for operating said member, and means '
cooperating with said motor to reduce the cur
rent through said element to zero as said mem'
ber approaches said predetermined point whereby
the deceleration of said motor is completed when_said predetermined point is reached.
28. The method of restoring the balance oi’> an
electrical system which comprises effecting ~an
adjustment for rebalance of the system in re~
sponse to an unbalanced electrical effect, and in
such manner as to decrease the unbalance until
balance is reestablished, and during the re
balancing adjustment opposing said unbalanced
electrical effect by ian electrical eifect whose
magnitude is a function of the rate of balancing
and an inñnitesimal calculus function of that
rate.
29. A systéin comprising a balanceable net
work, means in said network for producing an _
unbalanced electrical'effect, means‘adjustable to
effect rebalance of said network, _means respon
sive to said'unbalanced electrical e'iïect, driving
means controlled vby said responsive means to
effect adjustment of said adjustable means, and'
means operative during said adjustment to op
pose said unbalanced electrical eiïect by an elec
trical effect whose magnitude is a function of the
'
‘
2,113,436
rate of adjustment and an in?nitesimal calculus
function of that rate.
‘
_
30. ì A system comprising a balanceable network,
f'
ì means for producing an unbalanced electromotive
force in said network, an impedance adjustable
s
'to eñ'ectrebalance of said network, means re
i
.sponsive to'unbalance of said network, driving
` I
means controlled by said responsive means to
è
eiiect adjustment of said impedance, and a sec
‘
10 ondary network comprising a source _of electro
'
"
'
9
ondary network comprising a) generator, oper
ative during adjustment of said impedance, re
sistance and reactance for producing an elect-ro
motive force, in opposition to-said unbalanced
electromotive force, whose magnitude is a func
tion of the rate of adjustment of said impedance
and an inñnitesimal calculus function of that
rate.
«
»32. A system comprising a balanceable net
work, means for producing an unbalanced elec
tromotive force in said`network, an impedance
adjustable to _effect-rebalance df said network,
means responsive to unbalance of said network,
said unbalanced electromotive force, whose inag
nitude is a function- of the rate of adjustment of driving means controlled by said responsive
15 said impedance _and an inñnitesimal calculus func ',means to effect adjustment of said impedance,
motive force, resistance and reactance for pro
ducing an electromotive force, in opposition to
_
tion of that rate.
V
_
.
‘
31. A. system comprising a balanceable net
work, means forfproducing an unbalanced elec
tromotive force in said network, an impedance ad
20 justable to eiie'ct rebalance of said network,-means
,
'
-responsive to unbalance of said network', driving
'and a secondary network comprising a generator,
operative during adjustment of said impedance.
resistance and inductance for producing an elec
tromotive force, in opposition to said unbalanced
electromotive force, whose magnitude is depend w
ent upon different functions of the rate of said
means controlled‘by said responsive means to. l, adjustment.
efiect adjustment-_pi said‘impedance, and a sec
ALBERT J. WILLIAMS, JR.
Í)
I
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