close

Вход

Забыли?

вход по аккаунту

?

код для вставки
Jan. 18, 1949.
R, w, ENGSmOM
GOMPARI SON CONTROL SYSTEM
Filed Dec. 26, 1947
_
2,459,632
Patented Jan. 18, 1949
2,459,632
UNITED STATES PATENT OFFICE
2,459,632
COMPARISON CONTROL SYSTEM
Ralph W. Engstrom, East Petersburg, Pa., as
signor to Radio Corporation of America, a cor
poration 'of Delaware
Application December 26, 1947, Serial N 0. 794,006
1
14 Claims.
(Cl. 250—41.5)
‘My invention relates to improvements in energy
Still another object of my invention is'to pro
comparators and more particularly to a circuit
v'for comparing'a plurality ‘of energy sources to a
standard source for purposes of control.
“It is known in the prior art that energy dif-'
.feren'ces'may be measured or may be used to con
vide a circuit means characterized by two or
more electrical storage devices which are, one
after another, connected to the same energy
'trol various switching operations by means of
energy translating devices. There are at least
three general classi?cations of such energy-con
trol equipment: Static controls which function 10
under conditions of full'exposure or no exposure;
translating device, receiving from ‘its action a
change of their stored energies while said device
is correspondingly under the influence of a dif
ferent one of several sources of energy to'be com
pared with each other.
A further object of my invention‘ls to provide
circuit means for utilizing a comparison of
charge conditions'derived from a comparison of
dynamic ‘controls which are’ responsive'to changes
in degree only; and arrangements which are used
any energy source with a standard energy source
for ‘comparison purposes, it being necessary to
to control the operation of an electro-responsive
"take special precautions in'the latter class to in 15 device.
‘sure' measuring accuracy. My invention relates
A still further object of my invention is to pro
‘more particularly to devices within the last class.
vide an energy translating device for furnishing
Certain types of prior art apparatus utilize
strong currents to charge condensers for ‘com
either a plurality‘of energy translating devices in
a balanced circuit for establishing a center scale 20 parison of such charge conditions ‘to terminate
the ‘exposure or to control any switching opera
‘reading of a meter, or apply a balanced circuit
tion.
vto only one of such devices and ‘utilize equalizing
currents as manifestations of deviations deter
"mined ' by comparison.
Other types utilize a
In accordance with one embodiment of my in
vention a circuit is provided which utilizes a
known quantity of energy to charge or to delay 25 plurality of capacitors arranged to be sequentially
connected to an energy translating device and
the discharge of a ‘condenser through an energy
which receive from the action of such device a
translating device acting as a switch, presup
posing a predetermined knowledge of the con
change of their charge condition while the
energy translating device is correspondingly un
trolling quantity of energy and also being de
pendent 'uponthe sensitivity of the energy trans
der the in?uence of a different one of several
sources of energy for comparison of such charge
conditions. A qualitative comparison is made
when the condensers, which are connected to an
lating device.
It is ‘known that the sensitivity of most of the
usual energy translating devices is variable with
time. This fact is particularly troublesome in
electro-responsive device, attain the desired
charge conditions to initiate the operation-of the
those arrangements mentioned which depend ‘on i
vthe sensitivity of the device for their operation.
electro-responsive device.
A further di?iculty experienced in prior art ar
rangements is the lack of ‘certainty in operation
'due'to the relatively‘weak currents furnished by
‘the usual translating device of the light sensitive
‘and only by way of illustration, together with
other‘and further objects and advantages there
of, reference is made to the following descrip
ntype'unless coupled to'an amplifying system.
~A'cc'ordingly, itiis an object of my invention to
For a better understanding of my invention
tion taken in connection with the accompanying
drawings, ‘in which:
Figure 1 represents a schematic diagram of one
embodiment of my invention for comparing an
cuit acts as a comparator between a ‘standard 45 unknown light pulse't-o a standard light pulse.
‘gure 21s ‘a schematic diagram of another
pulse :of energy and an unknown pulse vof energy
embodiment of my invention for comparing an
independent .of the sensitivity of the energy
unknown light source to a steady standard light
translating device.
source.
‘Another‘object of ‘my invention is to provide
Referring to Figure 1 of the drawings, several
a-circuit means ‘of utilizing an energy translating 50
di?erent light sources I, are arranged with. a
devicerin such manner‘that the ‘circuit acts as a
suitable focusing means 2, so that the resultant
comparator between. a steady standard source
light will be directed‘ on the photo-emissive
ofenergy and'an unknownsource of energy inde
provide a circuit means of utilizing an energy
translating device in such manner thatthe cir
pendent 'of thesensitivity ofthe energy translat
in; device.
cathode 5. of assuitable photo-multiplier tube 3.
It
will be understood thatthis photo-multiplier
55 tube is merely one type of photo-sensitive device,
3
and that my invention is not restricted to the
use of such a tube, since any of the various well
known types of vacuum or gas-?lled cells with a
suitable ampli?er system could be employed.
The preferred type photo-sensitive device may
4
the equivalent of the comparison of the unknown
to the standard light source will manifest itself
in the form of some switching operation.
In order to complete the thyratron control cir
cuit so that current may ?ow through the thyra
tron after ?ring and yet prevent the condensers
be any type of electrostatically focused photo
l0 and H, from discharging before ?ring, the
multiplier.‘ tube 3, comprising a plurality of
cathode I4, is connected through a recti?er ll,
multiplier elements known as “dynodes” 4, a
to the mutual connection of the condensers l9
photo-emissive cathode 5, and an anode 6, and
and
H, at the ?xed reference point 29. Al
10
suitably connected to a power supply, not formthough other types of recti?ers may be used, I
ing part of this invention and not shown, where
prefer to use a diode ll’. The cathode Hi, of the
by a graduated voltage impressed across the tube
thyratron is connected to the anode iii, of said
elements will result in multiplication of the
diode, and the cathode it, of the diode completes
anode or output current.
circuit to the reference point 2&3.
The anode 6, of the photo-multiplier tube is 15 thethyratron
The described arrangement operates in the fol
connected to a switching arrangement 2!, which
lowing manner: With the switch arm '5, of switch
may be any type of selector that would produce
2|, connected to the pole member 8, a standard
the desired result when used with my system.
light pulse is ?ashed ‘from a light source at i
In accordance with the embodiment of my inven
illuminate the cathode 5, of the photo-mul
‘tion shown in Figure 1,1 prefer to use the single 20 to
tiplier tube 3. Illumination of the cathode re
pole, double-throw switch 2|, having pole mem
leases electrons which are directed by positive
bers 8 and 9, and a switch arm ‘I, connected to
electric ?elds to the ?rst dynode where they cause
the anode 5, of the photo-multiplier tube.
secondary emission which adds to the original
The pole members are connected to a compari
son circuit comprising a symmetrical arrange 25 electron stream. In this Way, the signal is multi
plied until it reaches the collector anode 6, which
ment of condensers l0 and l l, coupled to an elec
is coupled to the side of the symmetrical arrange
tro-responsive circuit using a thyratron l2, the
ment of the condensers l0 and H, which is con
operating level of which is established by the
nected to the pole member 8, of switch 2!. The
charge conditions of the condensers.
current output of the photo-multiplier tube flows
30
The pole member 8, is connected to one side
through the condenser Hi, to ground thereby
of a condenser I0, and the pole member 9, is con
charging said condenser and impressing a nega
nected to one side of a second condenser H, so
tive voltage on the control grid l3, of the thyra
that the switch arm 1, may connect either of the
tron, which voltage is equivalent to the quantity
condensers l0 and H, to the anode 6, of the
of the standard light reaching the cathode of the
photo-multiplier tube 3, in order to receive from
photo-multiplier tube and which serves to ?x one
its action a quantity of charge which is equivalent
of the parameters for establishing the desired
to the quantity of light to which the said photo
operating level for the thyratron.
multiplier tube is being subjected. The con
densers l0 and II, need not be equal in capacity 40 The switch arm '1, of switch 2!, is then con
nected to pole member 9, and light from some
and may vary in size depending on the applica
unknown light source as l is allowed to illuminate
tion and desired result. The other sides of the
the photo-multiplier tube cathode. The method
condensers are mutually connected to a point of
of alternately allowing the standard and unknown
?xed reference potential 20.
light sources to illuminate the photo-multiplier
In the relay control circuit which is coupled
tube cathode is not a part of this invention, and
"to the‘above described symmetrical condenser ar- ‘ any suitable means known to the art may be
rangement, I prefer to use an inert gas-?lled thy
used. The last mentioned illumination manifests
ratron I2, having a hot cathode M, which may
itself in the form of an electric current, in ‘the
be indirectly heated by a suitable ?lament (not
shown), a control grid l3, a shield grid 15, and _
an anode I 6. The control grid I3, is connected
to the mutual connection of the condenser 66,
' and the switch pole member 8, so that the charge
condition of the condenser In, which was derived
from the current ?ow resulting from the eXposure
of the photo-multiplier tube to a standard light
source, will impose a bias voltage on the control
grid thus establishing one of the conditions of the
. operating level for the thyratron.
same manner as indicated for the standard light
with the exception that the condenser H, is
charged and impresses a negative voltage on the
. .cathode I4, of the thyratron which again is equiv
alent to the quantity of the unknown light reach
ing the cathode of the photo-multiplier tube and
which serves to ?x another parameter for estab
lishing the desired operating level for the thyra
tron. A third control parameter is established
by the shield grid I5, and associated biasing bat
Another conditionv incident to establishing the 60 tery 22. Proper selection of a voltage for the thy
ratron anode 16, from a suitable power supply
aforementioned operating level is provided for
will ?x the boundary conditions at the desired
by connecting the shield grid l5, to the negative
operating level.
.pole of a biasing battery 22, whose positive pole
In the preferred embodiment of my invention,
is connected to the mutual connection of the con
denser l I, and the switch pole member 9. A third 65 the operating level established by the above-men
tioned parameters has been so chosen, that when
condition in establishing the thyratron operat
the voltage impressed on the control grid lit, by
ing level is provided for by connecting the cath
the charge on condenser Iii, which is derived from
ode M, to the mutual connection of battery 22,
the action of the standard light reaching the
'condenser H, and pole member 9. Finally, the
photo--multiplier tube, is equal to the voltage
thyratron anode I6, is shown returning through
impressed on the cathode M, by the charge on
relay operating coil 23, to a suitable power supply,
condenser II, which is likewise derived from the
not form'ing‘part of this invention and not shown,
action
of the unknown light reaching the phcto
'to further ?x the desired operating level where
multiplier tube, the thyratron will ?re and cur
by equal charge conditions on the condensers i0
rent will through the coil 23, of a relay'to actu
and l I, will initiate a ?ring of the thyratron, and
mama
fate‘ an“ armature '24. for ' closing or opening the
‘ relay. "The nring'of the 'thyratron is-independent
*of‘the'sensitivityof‘the photo-multiplier tube for
all'practical purposes; since such ?ring depends
"only on a comparison of-energy quantities stored - -
iii-condensers l0 "and -! Lwhich are derived from
the quantity of light illuminating» 'the photo
‘multiplier " tube ’ ~cathode regardless
of
time.
" Therefore‘,- any ’ variations ‘oi-sensitivity with age,
or tube changes,» will have ‘no-‘effect on the/com!
vparison, ' and vin the above-illustrated embodiment
ofmy’invention, likequantities ‘of energy will ‘?re
~the thyratron.
"The net result is tolcornpare the light energy
*of-‘thestandard light ‘pulse to that of the‘relay'
"terminated unknown light-‘pulse independently
"or ‘the sensitivity "of the photo-multiplier tube
-without~ amplifying its output/and to perform
suitable switching operations without the neces
sity ‘of previously determining the desired quan
tity of‘ a controlling light source._ This-may be
of particular interest in cases where ‘the photo
"multiplier' sensitivity changesiwith age or where
"it is-desired to ‘interchange thephoto-multiplier
tubes.
25
6
‘mutual connection'between the control grid“,
of the thyratron and condenser l0, and whose
cathode 21,'is"connected to a mutual connection
of'the resistance '28, and pole member 8, of the
switch 2|.
‘In ‘the above-described modi?ed embodiment
of my‘invention a steady illumination standard
I, is‘allowed to‘illuminate the cathode of‘ the pho
to-multiplier tube whose action charges the con
denser 10, ‘across resistance 28, in essentially the
'same manner as described for Fig. 1, except that
"theyalue of resistance 28, is chosen so that the
'condenser'will receive'only the desired quantity
of (energy from the steady illumination standard.
‘The recti?er 25, acts to prevent the discharge of
condenser-l0, through resistance 28, before con
denser I l, attains ‘an equal charge condition to
‘?re vthe 'thyratron essentially as described for
vFig. 1.
I-have mentioned hereinabove the application
*of my invention generally to various switching
operations and particularly in conjunction with
alight sensitive device for comparing a plural
ity' or light sources to control such switching
operations. However, my invention may be ap
pliedto any operation that can be controlled by
I It will» be obvious from'the above description
a comparison of energies or energy devices such
and operationthat‘ the-switch '2 I, may be man
as ‘antennas, thermoecouples, etc. In fact, it
ually, mechanically, or electrically controlled and
‘may be applied to any type of apparatus incor
- operatedior maybedrequency modulated, to at
~tain certain desired results. vIt may'also be de-' 80 porating a plurality of energy sources to be
compared ‘wherein the comparison in an inter
sirable,~dcpending on the magnitude of the charge
ruption or modi?cation of the exposure of one
"imparted to the two condensers duringoperation,
‘source‘as a result of its-action on an energy sen
to use va-three-way switch with a'third' position
sitive means manifesting itself as the equivalent
rfor'rfreturning "the ‘condenser to the initial "un
charged condition before each test. It will be ob- - 35 of its ‘exposure in an electro~responsive compar
ison Circuit.
yious ‘that although the "preferred novel system
lWhile I have shown and described what I con
illustrated in‘IFig. 1 and 'hereinbefore described
sider to-be the preferred embodiment of my in
.isprimarily-adaptedto be employed when it is
vention, it will be obvious to those skilled in the
desired to utilize a vcomparison-of light pulses, it
art that various changes and modi?cations may
- may'also‘beadaptedto comparisonwith a steady
"bemadewithout departing from my invention.
villumination standard as shownv in Fig.2.
and I therefore aim in the appended claims to
The system ‘shown'in Fig‘. '2 and in which‘ like
‘cover-all such changes and modi?cations as fall
numbers ‘refer to'likeparts functions in essen~
within'the'true spirit and scope of my invention.
tially the same manner and is basically the same
as the system illustrated in "Fig. '1.‘ ' The only dif 45 fiWhat I claim as new and desire to secure by
‘Letters Patent is:
~.ference between these 'twoisystems is the ‘addition
v~1. A comparison system comprising in com
in Fig. 2 of resistances 28 and*28;.and a diode 25,
in the condenser arrangement. illustrated by Fig.
1, so that thetim-e constant represented by the
product of the resistance 28. and capacity 10,
giR'zs Cm) will be less thanareasonable time for
the voltageldrop IRzs to :be established where I
isl‘the anode current vof: the'photo-multiplier tube
when illuminated with the standard calibration
light. ‘This is presumedin general to be lessz'than
one second. A resistance 29,--may also beladded
.in:the second charge circuit of=the condenser ‘I I.
but this is not necessary and it added must be
(of such a value that thetime-constantiRzs' Cu
Jbinatlon a plurality of symmetrically arranged
‘electrical storage devices, an energy translating
rdevice sequentially energizing each of said stor—
:age devices, and‘an electro-responsive device con
-'ne'cted between said symmetrical arrangement of
electricalstorage devices.
.2.‘ In a comparison system, a network compris
ing 'in combination a plurality of branch circuits
symmetrically connected about a point of ?xed
reference potential, an electrical storage device
in each oftsaid branch circuits, an energy trans
lating device ‘sequentially energizing each of said
will be greater than the time of the expected M) storage devices, and an electro-responsive device
connected between said symmetrical arrangement
light pulse to be measured or controlled to per
of electrical storage devices.
mit linear charging of the condenser H. An
3. In a comparison system, a network compris
other resistance 30, may be added in the thy
ing in combination a plurality of branch circuits
ratron plate circuit to limit high. currents after
?ring and its value will depend on the character 65 symmetrically connected about a point of ?xed
reference potential, a condenser in each of said
istics of the thyratron.
branch circuits, an energy translating device se
It will be obvious from the above description
quentially energizing each of said condensers, and
and operation that some means must be added
an electro-responsive device connected between
in the branch comprising the resistance 28, and
condenser H), to prevent the discharge of con 70 said symmetrical arrangement of condensers.
4. In a, comparison system, a network compris~
denser lll, before the comparison to- the charge
ing in combination a plurality of symmetrically
condition of condenser II, can be made. Here
arranged electrical storage devices, a light sensi
again, other types of recti?ers or unidirectional
tive device sequentially energizing each of said
current devices may be used, but I prefer to use
the diode 25, ‘whose anode 26, is connected to the 0 storage devices, and an electro-responsive device
7
connected between saidv symmetrical arrangement
of electrical storage devices.
5. In a comparison system, a network compris
ing in combination a plurality of symmetrically
arranged electrical storage devices, a photo-mul- -:
tiplier tube sequentially energizing each of said
storage devices, and an electro-responsive device
connected between said symmetrical arrangement
forapplying the charge of one of said condensers
to said control grid and the charge of the other
of said condensers to said cathode and a biasing
battery connecting said shield grid to said cath
ode, a recti?er connecting, said cathode to a point
of ?xed reference potential, and a source of power
connected to said anode.
12. A comparison system, comprising in com
- of electrical storage devices.
bination a plurality of symmetrically arranged
condensers, an energy translating device sequen
tially energizing each of said condensers, an elec
tron discharge device provided with an anode, a
cathode, a control grid, and a shield grid, means
for applying the charge of one of said condensers"
to said cathode and a ‘biasing battery connecting
device connected between said symmetrical ar
said shield grid to said cathode, a recti?er con
rangement of electrical storage devices,
necting said cathode to a point of ?xed reference
'7. In a comparison system, a network compris
potential, a relay operating coil, and a source of
ing in combination a plurality of symmetrically
power, said relay operating coil connecting the
arranged electrical storage devices, an energy,‘ 20 anode of said electron discharge device to said
6. In a comparison system, a networkcompr1s-. <10
ing in combination a plurality of symmetrically
arranged electrical storage devices, an energy
translating device, a switch sequentially con
meeting said energy translating device to each of
said storage devices, and an electro-responsive; :15
translating device sequentially energizing each of
source of power.
said storage devices, and an electro-responsive de
vice connected betWeen said symmetrical ar
rangement of electrical storage devices thereby
indicating a comparison of their stored energies
independent of the sensitivity of said energy
translating device.
'
13. he comparison system, a network com
prising in combination a plurality of branch cir
cuits symmetrically connected about a point of
?xed reference potential; a resistance, a recti?er,
and a condenser in one of said branch circuits,
and a second condenser in another of said branch
.
8. In a comparison system, a network compris
circuits; an energy translating device sequentially
ing in combination a plurality of symmetrically
charging each of said branch circuits, and an
arranged electrical storage devices, an energy, 30 electro-responsive device connected between said
translating device sequentially energizing each of
symmetrical arrangement of condensers.
said storage devices, and an electron discharge
14. In a comparison system, a network com
device connected between said symmetrical ar
prising in combination a plurality of branch cir
rangement of electrical storage devices. cuits symmetrically connected about a. point of
9. In a comparison system, a network compris
?xed
reference potential; a resistance, a recti?er,
ing in combination a plurality of symmetrically
and a condenser in one of said branch circuits,
arranged electrical storage devices, an energy
a second resistance and a second condenser in
translating device sequentially energizing each
another one of said branch circuits; an energy
of said storage devices, and a grid-controlled elec
tron discharge device connected between said,
symmetrical arrangement of electrical storage de
40
vices.
10. A comparison system, comprising in com~
bination a plurality of symmetrically arranged
condensers, an energy translating device se
translating device sequentially charging each of
said condensers through said resistances, and an
electro-responsive device connected between said
symmetrical arrangement of condensers.
‘
'
RALPH W.
ENGSTROM.
I REFERENCES CITED‘.
45
quentially energizing each of said condensers, an
The following references are of record in the
electron discharge device provided with a plu~
?le of this patent:
' ‘
rality of electrodes, means applying the charge
conditions of each of said condensers to different
UNITED STATES PA'I’ENTS
ones of said electrodes, and a biasing battery 50
Number
Name
Date
connected to another of said electrodes whereby
1,721,216
Hardy et a1. ______ _.'July 16, 1929
equal charge conditions of said condensers will
1,812,764
Story, Jr. _____;____ June 30, 1931
render said electron discharge device conductive.
1,840,500
' Ge?cken et a1 _____ __ Jan. 12, 1932
11. A comparison system, comprising in com
bination a plurality of symmetrically arranged 55 1,877,279 ' Dawson _________ __ Sept. 13, 1932
1,898,046
Ge?cken et a1 _____ __ Feb, 21, 1933
condensers, an energy translating device sequen
2,037,925
Rentschler _______ __ Apr. 21, 1936
tially energizing each of said condensers, anelec
2,069,505
Roberts ___________ .__ Feb. 2, 1937
tron discharge device provided with an anode, a
cathode, a control grid, and a shield ‘grid, means
2,225,353
vScheldorf ________ __ Dec. 17, 1940
2,417,023
_SWeet ________ _‘_____ Mar. 4, 1947
Документ
Категория
Без категории
Просмотров
0
Размер файла
694 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа