Aug. 19, 1947.
w, E, PAKALA
2,426,046
VAPOR ELECTRIC DEVICE
Filed Aug. 11, 1942
é‘IN 4 Poten ml
7Po'l‘entia
Time
WITNESSES:
8-.
.
’
INVENTOR
William
E. Paka la.
4
I
“3M 1M
ATTORNEY
2,426,046
Patented Aug. 19, 1947
UNlTED STATES PATENT OFFICE
2,426,046
VAPOR ELECTRIC DEVICE
to
Hills, Pa., assignor
William E. Pakala, ForestCorporation,
East Pitts
Electric
Westinghouse
burgh, Pa., a corporation‘ of Pennsylvania
Application August 11, 1942, Serial No. 454,372
10 Claims. (01. 315-166)
' the component currents and resulting excitation
1
My invention relates to a vapor-electric device
and particularly to an excitation system for im
proving the operating characteristics of a vapor
current secured by my excitation system.
In the illustrative embodiment of my inven
arc valve device.
of a suitable transformer means l2 and the flow
of current through the transformer I2 is con
tion, an alternating-current circuit 10 is con
nected to a direct-current circuit II by means
In the operation of vapor-arc valve devices,
two types of excitation have heretofore been
utilized. The ?rst, and for many years, the
standard excitation system, has been a system
'
substantially constant, continu
ous excitation of a value su?icient to secure pick
up of the arc to any positive anode. Usually the
actual time of pickup was controlled by means
of a suitable shield and grid system. The sec
trolled by means of a plurality of vapor-electric
valves 13. Each of the vapor-electric valves l3
comprises a main anode l4 and cathode IS with
The anode I4 is
10 in an evacuated container IS.
ond method of excitation is the recently invented
make-alive type in which the cathode spot is not
maintained but reinitiated at the beginning of
each conducting half cycle.
preferably surrounded by a suitable shield l1.
Also each valve I3 is provided with a starting
electrode
With the first method of excitation, it was nec
essary to maintain a heavy protective grid sys
tem in order to reduce the probabilities of are
back during
'
20
herein
'
‘
'
resistant make-alive type and a suitable keep
alive electrode 2!. The starting electrode 20 and
the keep-alive electrode 2| are preferably con
This heavy
nected in parallel to a suitable source of con
tinuous exciting current herein shown as a full
wave recti?er 22 fed from a suitable alternat
ing-current source such as the alternating cur
rent line H].
While any suitable number of valves l3 may
be utilized, I have herein shown a pair of alter
grid system resulted in excessive arc drop losses
in the valve device. When the make-alive sys
tem is utilized, the shielding could be reduced 25
to a minimum but the requirements of striking
the cathode spot and producing vthe necessary
vapor to insure pickup required excessive im
pulse energy.
In the excitation system according to my in 30
vention, a continuous excitation current is pro
vided of su?icient intensity to maintain a cath
of too low intensity to maintain
nately conducting valves 13, while it is apparent
that any number of pairs of valves l3 may be
utilized each pair having a similar excitation
system. In order to divide the direct-current
between the pairs of exciting electrodes 2|, a high
reactance 23, preferably of the coil type, is in
serted between the pair of exciting electrodes
2|, the positive side of the direct-current source
22 being connected to a mid tap 24 of the re
actor 23 the other side of the direct-current
periodic current impulse is superimposed on the 35 source 22 being connected to the cathodes 15
of the valves l3. In order to secure a periodic
continuous excitation to produce the necessary
alternating current impulse, I have provided a
ionization to secure pickup at the beginning of
‘
produce pickup, and a
wave distorter impulsmg system herein shown as
of the reactor type, while it is obvious that any
provide an excitation circuit having improved 40 suitable impulsing device may be utilized. The
preferred wave distorter system comprises a
operating
characteristics.
source 25 of alternating current having a capac
. It is a further object of my invention to pro
itor 26 connected across its terminals and a suit
vide an exciting system requiring the mini
able impedance 21 for controlling the ?ow of
mum of excitation energy to secure reliable op
45 current from the alternating-current source 25
to the capacitor 26. A voltage sensitive vari
eration.
It is a further object of my invention to pro
each conducting half-cycle.
It is accordingly an object of my invention to
vide a direct-current excitation system having
an alternating-current impulse superimposed
thereon.
Other objects and advantages of my invention
will be apparent from the following detailed de
scription taken in conjunction with the accom
panying drawing, in which:
I Figure 1 is a schematic illustration of a vapor
.electricsystem according to my invention.
' Figs. 2,3“ and dare graphical illustrations of
able reactor 28 is inserted between the alternat
ing-current source 25 including the capacitor
26 and the excitation electrodes, 26 and 2| to
control the flow of current from the source 25
to the electrodes 20
This voltage sen
sitive impedance 28 is usually in the form of a
saturable reactor which, at low voltages, offers
a very high impedance to the flow of current,
but when saturating potential is supplied a sat
23,426,646
urating current ?oWs
duces its impedance to in the reactor and re
keep-alive electrode 2| and the flow of current
a
to the keep-alive electrode 2| will open the cir
cuit interrupting device 35 in series with the
starting electrode 20. The other half-cycle from
or if the circuit interrupters 35
are closed between the starting electrodes 20,
and returns through the cathode connection to 7
While I have shown and described a speci?c
embodiment of my invention, it will be apparent
Then at the instant
I claim as my invention:
1. An electric current translating system in
_ on right-hand valve
l3. » Unless the negative'impulse is bypassed it 20 terconnecting a direct-current circuit and an
attempts toflow through‘ the electrodes 2'0-2!
alternating-current circuit comprising-at-least a
of the right-hand valve I3, and reduces the total
current tov such a value as to interrupt current
flow ‘to electrode 2|~of the right-hand valve I 3.
In order to prevent reverse current ?ow through 25
the exciting electrodes Zlland 2| which receives
7
polarity sensitive circuit
isprovided in shunt with the exciting electrodes
,
Preferably this polarity sensitive
shunt 30 is in the form of a unidirectional con
30'
ductor such as a dry recti?er.
In,v order to control the time instant of the
application of the ionizing impulse, I prefer to
providea suitable phase shifting device 3| in
current -be—
tween the mid-point vof said reactor-and the
series With the alternating-current source 25. I 35 cathodes of said valves.
also prefer to provide
'
‘
'
2. An electric current translating ‘system in
terconnecting a direct-current circuit and an
40
alive electrode 2|. In this
electrode 2!] will operate only until such time as
valve, a keep-alive velectrode in each ‘valve-a
source of alternating potential, circuit means
including a saturable reactor for connecting said
source of alternating-current potential to said
starting electrodes. and said keep-alive =elec
in open position.
The
onlyoperates at initial starting of the valve, or
restarting in the event of current interruption
through keep-alive electrode 21. -
It is sometimes desirable to provide a control 55 3. An ignition system fora vapor-electric valve
potential to the anode shield 11.
comprising a, starting electrode in-said valve, an
mum positive potentialat the time of the ioniz
60.
ing impulse as shown in Cox et al., Patent
2,259,293.
starting electrode.
"
65
4. An electric current translating systemi-for
interconnecting a direct-current ‘circuitand-an
alternating-current circuit
‘
pair ‘of valves ‘l3, and at ,the proper interval a 70
current impulse 4| 'will bedelivered to ‘one of
the starting electrodes 20. ‘This current impulse
4| ‘will be su?iciently high tolinitiate 'a cathode
opposite terminals of -said-alternating~current
spot after which the current will pickup to the 75 source to the exciting electrodes of the-respective
‘valves, a source ‘of direct current; a reactor-con
2,426,046
said exciting electrode, the potential of said
source of direct current potential being suf?cient
nected across the output terminals of said cir
cuit, a tap intermediate the ends of said reactor
and circuit means for impressing the potential
of said source of direct current between said tap
and the cathodes of said valves.
5. An electric current translating system for
interconnecting a direct-current circuit and an
alternating current circuit comprising a pair or‘
to normally maintain a keep-alive arc in said
valve, a source of periodic potential and means
for impressing the potential of said source of
periodic potential on said exciting electrode for
periodically re-enforcing the excitation in said
valve, a starting electrode in said valve and means
responsive to current flow to said exciting elec
trode to determine the energization of said start
10
valve including a main anode and cathode and
ing9.electrode.
An exciting system for a vapor-electric valve
exciting electrodes including an electrode in con
comprising a. source of substantially constant di
tact with the cathode and an electrode spaced
rect current, a source of alternating current,
from the anode and cathode, a source of alter
wave distorter means energized from said source
nating-current potential, a circuit for connecting
alternately conducting vapor-electric valves, each
opposite terminals of said alternating-current
source to the exciting electrodes of the respective
valves, a source or direct current, a reactor con
nected across the output terminals of said cir
cuit, a tap intermediate the ends of said reactor
and circuit means for impressing the potential of
or direct current between said tap
or said valves, circuit inter
rupting means in series with the electrodes in
contact with the cathodes and means energized
by current flow to the associated spaced elec
trode for actuating said circuit interrupting
of alternating current for producing periodic im
pulses of short duration, a starting electrode in
said valve, means for impressing the impulses
of short duration on said starting electrode for
initiating exci ation in said valve, an exciting
20 electrode in said valve, connections for impressing
the potential of said source of direct current on
said exciting electrode for maintaining a keep
alive arc of low intensity in said valve and
means for impressing the output of said wave
25 distorter means on said exciting electrode for
means.
6. An exciting system for a vapor-electric valve
comprising a source of substantially constant di
rect current, a source of alternating current, wave
distorter means for producing periodic current
impulses of short duration from said alternating
periodically increasing the intensity of excita
tion in said valve.
10. An exciting
valve comprising a source of substantially con
stant direct current, a source of alternating cur
rent, wave distorter means energized from said
source of alternating current for producing peri
odic impulses of short duration, an exciting elec
current source, a starting electrode in said valve,
an exciting electrode in said valve, and connec 35 trode in said valve, connections for impressing
the potential of said source of direct current on
tions for impressing said direct current and said
said exciting electrode for maintaining a low de
gree of excitation in said valve and means for im
pressing the output of said wave distorter means
on said exciting electrode for periodically in
40 creasing the degree of excitation in said valve,
means.
.
'7 . An ignition
system for a vapor-electric valve
a starting electrode in said valve and switching
comprising a keep-alive electrode in said valve,
means responsive to current flow to said excit
a source of direct current exciting potential,
current impulse in parallel on said electrodes,
and phase shifting means between said source of
alternating current and said wave distorter
ing electrode for controlling the energization of
rent to said keep-alive electrode, the potential of 45 said starting electrode. WILLIAM E. PAKALA.
said source of direct current potential being suffi
means for connecting said source of direct cur
cient to normally maintain a keep-alive arc in
said valve, a source of periodic potential, a make
alive electrode in said valve, means for connect
ing at least said source of periodic potential to
said make-alive electrode for initiating excitation
REFERENCES CITED
The following references are of record in the
5° ?le of this patent:
UNITED STATES PATENTS
in said valve and means for impressing the po
tential of said source of periodic potential on said
keep-alive electrode for periodically re-enforcing
Number
1,694,244
55 2,246,181
the excitation in said valve.
2,291,092
8. An ignition system for a vapor-electric valve
2,300,872
comprising an exciting electrode in said valve, a
source of direct current exciting potential, means
for connecting said source of direct current to
Name
Date
Alexanderson ______ __ Dec. 4,
Morton __________ __ June 17,
Cox et a . __________. July 28,
Cox ______________ __ Nov. 3,
1928
1941
1942
1942