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Патент USA US3023300

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Feb. 27, 1962
o. H. SOLES ETAL
3,023,291
COMPRESSED GAS CIRCUIT INTERRUPTER
Filed Aug. 31. 1959
5 Sheets-Sheet 1
Feb. 27, 1962
o. H. sou-:s ETAL
3,023,291
COMPRESSED GAS CIRCUIT INTERRUPTER
Filed Aug. 31, 1959
5 Sheets-Sheet 2
Feb. 27, 1962
o. H. SOLES ETAL
3,023,291
COMPRESSED GAS CIRCUIT INTERRUPTER
Filed Aug. 31, 1959
5 Sheets-Sheet 3
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Feb. 27, 1962
o. H. soLEs ETAL
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3,023,291
COMPRESSED GAS CIRCUIT INTERRUPTER
Filed Aug. 31, 1959
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Feb. 27, 1962
o. H. SOLES ETAL
3,023,291
COMPRESSED GAS CIRCUIT INTERRUPTER
Filed Aug. 51, 1959
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United States Patent 0 ” 1C6
3,623,291
‘Patented Feb. 27, 1962
1
2
3,023,291
described, means for reclosing the interrupter contacts
COMPRESSED GAS CIRCUIT INTERRUPTER
Otto H. Soles, East Pittsburgh, and Richard E. Kane,
Monroeville, Pa., assignors to Westinghouse Electric
Corporation, East Pittsburgh, Pa., a corporation of
Pennsylvania
Filed Aug. 31, 1959, Ser. No. 837,227
6 Claims. (Cl. 200—148)
and the impedance contacts substantially simultaneously
rather than sequentially.
More speci?cally, it is an object of this invention to
provide in a compressed gas circuit interrupter of the
type described, a reclosing valve attachment for effect
ing reclosing of the impedance contacts in direct re
sponse to reclosing of the dumping means after a circuit
interruption.
This invention relates generally to compressed gas 10
Still more speci?cally, it is an object of this invention
circuit interrupters, and, more particularly to compressed
to provide in a compressed gas circuit interrupter of the
gas circuit interrupters particularly adaptable for auto
type described, a reclosing valve responsive to an open
matic reclosing operation.
ing operation of the ?rst dumping means to set up the
This invention is an improvement upon the compressed
impedance contacts for opening only after the main con
gas circuit interrupter as disclosed and claimed in co
pending application Serial No. 590,066, ?led on June 7,
1956, by Benjamin P. Baker, now Patent No. 2,965,735,
issued December 20, 1960, and which is assigned to the
15 tacts have opened, and which valve responds to a clos
ing operation of the main dumping means to effect re
closing of the impedance contacts independently of the
main contacts.
same assignee as the present application. Therein is dis
Other objects will, in part, be obvious and will, in
closed for each pole of a three-phase interrupter a pres 20 part, be explained hereinafter.
surized tank containing an interrupter assembly, each
For a better understanding of the nature and objects
assembly comprising a main current interrupter unit hav
of the invention, reference may be had to the following
ing a movable contact mounted on a piston and an im
detailed description, taken in conjunction with the ac
pedance interrupting unit having a movable contact on
companying drawings, in which:
a piston and connected in parallel with the main current 25
FIGURE 1 is a vertical sectional View taken through
interrupter. A ?rst dumping means is operable to eX~
one pole of a three pole interrupter;
haust gas from the pressurized back side of the current
FIG. 2 is an enlarged vertical sectional view taken
interrupter piston to eilect opening movement of the mov
through the right-hand interrupting assembly of the
able main contact, thus forcing the current through the
parallel disposed impedance interrupting unit. A valve
responsive to movement of the interrupter piston operates
to exhaust the gas from the pressurized back side of the
impedance piston to effect opening of the impedance con
tact only after the opening operation of the main con
pole unit illustrated in FIG. 1, taken substantially along
30 the line II——II of FIG. 1;
FIG. 3 is an inverted plan view of the interrupter
assembly of FIG. 2;
FIG. 4 is an enlarged view of the dump-valve mecha
nism and the latch therefor, which is operated by the
tact, thus maintaining the impedance in the circuit for 35 conducting bridging member, the dumpmalve being illus
a particular time after an opening operation of the inter
trated in the closed circuit position;
rupter contacts to control the rate of rise of recovery
voltage to‘ prevent voltage build-up across the interrupter
FIG. 5 is a top plan view of the dump-valve of FIG. 4;
FIG. 6 is a cross sectional view of the reclosing valve
as connected in the compressed air system of the circuit
unit. The operation ‘of the ?rst dumping means is ef
fected by a conducting cross-arm which moves down 40 interrupter of FIGS. 1 through 5;
wardly through lap-type sliding contacts until open
ing of the contacts has been obtained whereafter con
tinued downward motion of the cross-arm releases the
main dumping means which returns to its original con
FIG. 7 diagrammatically illustrates the current flow
through one interrupter assembly in the closed-circuit
position of the interrupter;
‘
FIG. 8 diagrammatically illustrates the initial opening
dition, and whereafter the cross-arm disengages the sliding 45 of the main contacts associated with the main current
contacts and moves to full open position. The reseat
interrupting unit, during the initial portion of the open
ing of the main dump-valve restores pressure behind the
ing operation;
main interrupter contact piston which closes the main
FIG. 9 diagrammatically represents the interruption
contacts and recloses the valve, whereafter incidental leak
of the current through the impedance interrupting unit
age of gas into the valve chamber restores pressure be 50 at a subsequent stage in the opening operation;
hind the movable impedance piston to reclose the mov
FIG. 10 diagrammatically represents the conditions
able impedance contact.
which take place following a separation of the lower
Where it is desired to utilize the system of the above
bridging member from the disconnecting contacts of the
described apparatus of the copending application on
interrupting assembly, while the continuing gas blast
automatic reclosing duty, the relatively large amount of
maintains the circuit open at the main current interrupt
time consumed in reclosing the contacts and the imped
ing unit and at the impedance interrupting unit; and
ance contacts in the described sequence provides a dis
FIG. 11 diagrammatically illustrates the fully opened
advantage in that the connection of the cross-arm for
circuit position of the interrupter wherein there is a re
opening and closing operation in response to automatic
closure of the contacts in the main current and impedance
reclosing apparatus may effect reclosing of the circuit to
interrupting
units and the disconnecting gap is provided
begin another interruption operation before the impedance
by the bridging member.
contacts have had time to reclose, thus eliminating the
The basic compressed gas circuit interrupter of this
protection against voltage build-up as normally provided
application is identical to that disclosed and described in
by the impedance.
Accordingly, it is an object of this invention to pro
vide in a compressed gas circuit interrupter of the type
the hereinbefore mentioned copending application by
Benjamin P. Baker, and will now be described as the en
vironmental apparatus for the present invention.
described, means for rapidly reinserting the impedance
Referring to the drawings, and more particularly to
means in the circuit after a circuit interruption operation
FIG. 1 thereof, the reference numeral 2 refers to one
to thus adapt the compressed gas circuit interrupter for
of three pressurized tanks or enclosures, each tank relat
use on automatic reclosing duty.
70 ing to one pole of a three pole interrupter. A pneumatic
More speci?cally, it is an object of this invention to
operating mechanism (not shown) is provided to effect
provide in a. compressed gas circuit interrupter of the type
longitudinal, horizontal motion of an operating rod 18,
8,023,291
9
I)
which moves to simultaneously actuate the interrupting
asemblies within each of the tanks 2. Associated with
each tank 2 is a pair of hollow terminal bushings 27 each
topped by an exhaust muf?er 218 including a bushing
type current transformer 28 for connection to a relay
mechanism (not shown) associated with the previously
described pneumatic mechanism. It will be observed that
each hollow terminal bushing 27 has a hollow terminal
stud 32 associated therewith constituting an exhaust con
10
duit leading out of the pressurized tank 2.
Referring next to the pole unit 33, illustrated in PEG.
1, which may be the middle pole unit of the three-phase
compressed-gas circuit interrupter. It will be observed
that disposed interiorly within the enclosure or tank 2
are a pair of interrupting assemblies 34, which are elec
trically interconnected by a conducting bridging member
36. The conducting bridging member 36 is vertically
4
the bridging member 36 and the disconnecting ?ngers 56
is suf?cient to hold the voltage and to maintain the circuit
open. It will be obvious that during a closing operation
the bridging member 36 will move upwardly, and the
moment it contacts the disconnecting ?ngers 56 there will
be an immediate re-establishment of the circuit through
the interrupting asembly 34, since the relatively movable
contact structures 49, 50 associated respectively with the
main current interrupting unit 4d and the impedance inter
rupting unit 45 will already have been closed.
Referring more particularly to FIGS. 1, 2 and 3, it
will be noted, referring particularly to FIG. 2, that the
contact foot 43 is ?xed to a hollow exhaust chamber 53.
The hollow exhaust chamber 58 is'in free communication
with the region interiorly of the hollow terminal bushing
27. Secured to the lower end of the hollow exhaust
chamber 58 is a relatively stationary ori?ce contact 59
constituting a part of the relatively movable contact
structure 49 of the main current interrupting unit 44.
actuated in a reciprocal manner by an insulating lift rod
37, which may be connected to a straight line linkage 38,
which may be of the type illustrated in United States 20 The relatively stationary ori?ce contact 59 is provided
by an ori?ce plate 6%, which is bolted as at 61 to the
Patent 2,743,337. The linkage 38 is, in turn, connected
lower end 62. of the exhaust chamber 58. This lower
to the previously mentioned horizontally movable operat
ing rod 18.
Secured to the left-hand side of the tank 2, as viewed
in FIG. 1, is a potential device 39 having a connection
41 with a suitable potential tap 42 provided by the ter~
minal bushing 27.
It will be observed that associated with the inner end
end of the exhaust chamber 53 has one or more ribs 63
integrally formed therewith, which serve to hold ?xedly
in position an arc terminal 64, the function of which will
be described hereinafter. Preferably the arc terminal 64
has a bore 66 passing therethrough to assist in are ex
tinction and to provide less resistance to the exhaust of
gas.
of each hollow terminal bushing 27 is a contact foot 43,
Associated with the other side of the exhaust chamber
30
which serves to support the interrupting assembly
58, as viewed in FIG. 2, is a relatively stationary ori?ce
As shown in detail in FIG. 2, the main current inter
contact 67, constituting a part of the relatively movable
rupting unit 44 and the impedance interrupting unit 45
contact structure 56' of the impedance interrupting unit
are in electrical parallel relationship. The reason for
45. This relatively stationary ori?ce contact 67 is pro
this is more apparent from an inspection of FIGS. 7-11
35 vided by an ori?ce plate 69' bolted by bolts 76 to an aper
of the drawings.
tured Wall 71 of the exhaust chamber 58. As shown,
Referring to FIG. 7, it will be observed that the bridging
gaskets 72 and 73 associated with the ori?ce plates 69
member 36 makes contact with the lower end of the in
terrupting assembly 34. The relatively movable contact
structure 49 of the main current interrupting unit M» is
closed. Also the relatively movable contact structure 50
of the impedance interrupting unit 45 is also closed. It is
obvious, therefore, that in the closed-circuit position of
the interrupter that the current passes through the main
current interrupting unit 44- in he manner indicated by
the arrows 52.
FIG. 8 shows the state of affairs during the initial por
tion of the opening operation, when the bridging member
36 moves downward slightly to e?ect opening of the mov
able contact structure 49 in a manner described herein~
after, and thereby causes a blast of gas to ?ow through
the contact structure 49 and extinguish the main current
arc. This action forces the current to flow through the
impedance interrupting unit 45 in a manner indicated by
the arrows 53. However, because of the presence of the
impedance 54, the amperage of the current is considerably
reduced and the power factor is improved.
FIG. 9 illustrates the conditions arising when the rela
tively movable contact structure '50 of the impedance in
terrupting unit 45 opens, by means hereinafter described,
and 6t}, respectively, insure a gas-tight connection. As
mentioned previously, the pressure within the tank 2, and
consequently in the region around the interrupting as
semblies 34-, is at
relatively high pressure, say 250
pounds per square inch. The pressure within the region
74 of the hollow exhaust chamber 58 and in the region
within the hollow terminal stud is at a considerably lower
pressure, say two or three atmospheres gauge, as con
trolled by a control valve (not shown). As mentioned
heretofore, there is a free communication from the region
7!; within the exhaust chamber 58 through the contact
foot
and into the interior of the hollow terminal
stud. It is, therefore, necessary to insure a gas-tight seal
between the region 77 within the tank 2 and the region
74 within the hollow exhaust chamber 58.
Encircling the relatively stationary ori?ce contact 59 is‘
a gasket 78 serving as a blast-valve seat, which is re
tained in place by a retaining ring
Cooperating with
the blast valve seat 78 is a movable blast-valve 31. The
movable blast-valve S1 constitutes the upper portion of
'a ?rst piston member 82, which slides within an oper
ating cylinder 83. The ?rst piston member 82 is adapted
to thereby effect a blasting of the residual current are 60 to strike a plurality of shock washers 35 at the end of
the opening stroke. The operating cylinder 83 is bolted,
drawn at the contact structure 56 effecting its extinction.
by one or more bolts 86, to a dump-valve casting 87. The
It will be noted that the bridging member 36 still continues
to make contact with the disconnecting ?ngers ‘56 of the
dump-valve casting 87 is provided with a plurality of
upstanding ?ngers 38, which bear against a side wall por
interrupting assembly, but current ?ow through the inter
65 tion 89 of the ?rst piston member 32 to collect current
rupting assembly 34 has ceased.
therefrom. Disposed interiorly of the ?rst piston mem
FIG. 10 illustrates a subsequent step in the opening
ber 82 is an annular segmental main contact 90, having
operation where the bridging member 36 has parted con
?ngers $41 which in the closed-circuit position of the intertact with the disconnecting ?ngers 56, but during this
rupter contact a vertical wall surface 91E of the ori?ce‘
time the gas blast, indicated by the arrows 57, continues
plate 64.}. Thus the main current, which passes through
to prevent any are reignition and to maintain the circuit 70
open.
FIG. 11 illustrates the fully open-circuit position of the
interrupter when, by means hereinafter described, the gas
the relatively movable contact structure 49 of the main
current interrupting unit 44-, passes between the annular
main contact git comprising resilient ?ngers
and the
vertical wall portion 91 of the ori?ce plate 6%.
blast has ceased, and the contact structure 4%, Sill has
Disposed concentrically within the annular main con:
reclosed. However, the isolating gap between the end of 75
5
‘3,023,291
tact 90 is a rod-shaped arcing contact, or stud 92 having
an upper arc-resisting portion 93. The arc-resisting por
tion 93 cooperates with the aforementioned arcing termi
nal 64 to locate the main current are axially through the
ori?ce of the ori?ce contact 59.
the upper plate 148 of the resistor assembly 54 has a ter
minal stud 149, to which is secured a ?exible connector
150. The other end of the ?exible connector 150 is
clamped to the lower threaded end of the contact stud 151
of movable impedance contact 126 which passes through
an aperture 152 of an upstanding guide portion 153 of
Biasing the main movable contact 915, comprising the
annular main contact 919 and the arcing contact 92,, in an
the casting 136.
upward closing direction is a battery of compression
At the upper end of the movable impedance contact 126
springs 96, having their lower ends seated within a recess
is an arc-resisting tip portion 154, which serves as an arc
97 of the dump-valve casting 87. The springs 96 con 10 terminal during the opening operation.
stitute a biasing means to maintain the relatively mov
The dump-valve means for exhausting high-pressure
able contact structure 49 closed except when compressed
gas is dumped from the rear side of the ?rst piston mem
ber 82 by operation of a ?rst dump-valve means, here
inafter described.
The rod-shaped arcing contact 92 has a reduced ex
tension 98 which passes through an aperture in a slotted
gas from the region 122 below the ?rst piston member 82
will now be described. As mentioned previously, a con
ducting bridging member 36 electrically interconnects
15 the two interrupting assemblies 34.
cup-shaped member 191, and which also passes through
an aperture provided at the lower end of the ?rst piston
member 82. A nut 196 is threaded along a threaded
portion of the reduced stem 98. The lower end of the
stem 98 has a recess 103 interiorly provided with threads,
which may accommodate a threaded tool utilized in the
assembly process to compress the springs 96.
During the actual operation of the interrupter, the
cavity 198 in the stem 93 may strike a valve stem 113 of
a second drum-valve 115 biased to its closed position
against a valve seat 116 by a compression spring 117.
The second dump-valve 115 has a lower guide stem por
The outer extremity
of the bridging member 36 has a vertical hole provided
therein. A latching pin 158 shown in FIG. 1 is ?xedly
secured diametrically across the hole and is used to latch
onto a latch member 159, the con?guration of which is
more readily ‘apparent from an inspection of FIG. 4 of the
drawings. The latch member 159 is pivotally secured by
a pivot pm 160 to a lower ?attened portion 162 of a dump
valve stem 163. The upper end of the dump-valve stem
163 actuates a ?rst dump-valve 164, comprising an annular
gasket member retained in place by a washer 165 and a
nut 166 threaded about an upper threaded extension 167
of the valve body ‘168. The ?rst dump-valve 164 slides
within a valve casing 169 having a lateral outlet opening
171. The opening 171 communicates with a connector
tion 118, which is guided through an aperture 119 pro 30 172 bolted, as at 173, to the valve casing 169. The con
vided in a lower cap 121}, as shown more clearly in FIGS.
nector 172 has an opening 174, within which is secured
2 and 3 of the drawings. The lower cap 129 is secured
a dump-valve pipe 175, more clearly shown in FIG. 3 of
by bolts 121 (FIG. 2) to the durnp—valve casting 87.
The actuation of the second dump~valve 115 by open
ing movement of the main movable contact 95 effects an
intercommunication between the region 122 under the
?rst piston 82 and the region 123 under a second piston
member 125 associated with a movable impedance con
tact 126, more clearly shown in FIG. 2 of the drawings.
This is brought about by an exhaust pipe 127 which con
nects through a connector 127’ with a second pipe 129
(FIG. 3) which communicates through an aperture (not
shown) of the dump-valve casting 87.
The movable impedance contact 126 also includes an
annular blast-valve portion 131, which cooperates with a
blast-valve seat 132 provided by a gasket and inserted
within the ori?ce plate 69.
The movable impedance contact 126 is biased upwardly
toward its closed position by a compression spring 133
having its lower end seated within a cavity 134 provided
in an operating cylinder casting 136. This casting 136 is 50
secured by clamp lugs (not shown) to a semi-cylindn'cally
shaped insulating support plate (not shown). The lower
end of the latter support plate is secured by similar clamp
lugs (not shown), to the lower base casting plate 139 as
shown in detail in U.S. Patent 2,965,735, previously men
tioned. Disposed between the operating cylinder casting
the drawings.
The dump-valve pipe 175 is secured into an opening
176 of the dump-valve casting 87, and hence communi
cates with the region 122 below the ?rst piston member
8
Referring again to FIG. 4, the ?rst dump-valve 164 co
operates with a valve seat 177 provided by a cap 178
having a recess 180, within which is a packing 181 com
pressed by a gland 182. The gland 182 is bolted into place
by bolts 133. The gland 182 and the cap 178 surround
the lower end of a conduit ‘184, which extends upwardly
between the main current interrupting unit 44 and the
impedance interrupting unit 45 and leads into the hollow
exhaust chamber 58. Referring to FIG. 2 in this connec
tion, it will be observed that the upper end of the conduit
184 extends through an aperture 135 of the exhaust cham
ber casting 58, and a packing 186 and a gland 187 se
cured by bolts 18% insures a gas-tight connection thereat.
As mentioned previously, the latching pin 158 associ
ated with the extremity of the conducting bridging mem
ber 36 latches to a nose 189 of a latching member 159
and forces the ?rst dump-valve member 164 downwardly
against the upward biasing action exterted by a battery of
compression springs 191 disposed within the valve casing
169. The latching member 159 has an upper bifurcated
portion 192, the legs of which 193 straddle the reduced
54, in this particular instance including a plurality of
section 162 of the dump<valve stem 163. Also, the bi
resistor grids 141. These resistor grids 141 are stacked
furcated portion 192 has a pair of integrally formed hook
in superimposed relation upon a pair of insulating tie rods 60 members 194, which engage a cross-pin 195 supported by
142 and ‘are maintained in the compressed condition by
a pair of bracket members 196 integrally formed with a
a spring plate ‘143 which slides upon the tie rods 14-2, and
lower cap 197. The hook members 194 have extending
which serves as an upper seat for a plurality of compres
thereacross a pivot pin 199, to which is pivotally con
sion springs 14-4. The lower ends of the compression
nected a spring guide rod 200. A washer 201 encircles
springs 144 seat in a plurality of recesses 146 provided 65 the spring guide rod 260 and bears against the upper ends
of the hook members 194.
in a base casting 147, to which is secured the lower ends
of the tie rods 142.
‘During the opening operation, the latch member 159 is
pulled downwardly by the latch pin 158 movable with the
Each resistor grid 141 is in a zigzag shape, and the
conducting bridging member 36 against the opposition
general method of interconnecting. the resistor grids 141
is described and illustrated in United States Patent 2,632, 70 a?orded by the compression springs 191. This opens the
?rst dump-valve 164 away from its seat 177 to permit
078. Reference may be had to this patent for a detailed
the region 202, which is initially at high pressure to com
knowledge of the method of assembly and construction of
municate
with the region 203, the latter being in free
the resistor grids 141, which construction forms no part
communication with the region 74 within the exhaust
of the present invention. It will be noted, however, that 75 chamber 58.
136 and the bottom casting 139 is an impedance assembly
3,023,291
1
The compression spring 2%, encircling the spring guide
rod 2%, insures that the stop pin 295 disposed trans
versely between the legs 193 will be maintained against the
valve stem 163 insuring that the nose 189 will remain
under the latch pin 158 until the hook members 19-45
strike the cross-pin 195. When this occurs, the latch
member 159 ‘will pivot in a clockwise direction about the
cross-pin 195 releasing the pin 15$. The compression
O
Q
ment of the latch members 159 effects opening of the
?rst dump-valves 164 to open the connection between
the region 2% (FIG. 4) and the region 232, which com~
municates directly with the region 122, on the lower
side of the ?rst piston 82‘. Because high pressure exists
within the region 7'7 within the tanl; structure 2, and
because there is now a low pressure within the region 122,
the ?rst piston member 82 will be forced downwardly
to open the movable blast-valve 31 away from its cooper
springs 191 will, at this time, attempt to immediately re
turn the ?rst dump-valve 1645 to the closed position against 10 ating blast-valve seat '73. This will provide a radially
inward blast of gas through the ori?ce contact 59 the
the valve seat 177, but this upward motion will be re
moment
the annular segmental main contact 9%} sepa
tarded because of high pressure gas which has entered
rates away from the vertical main contacting surface 91
through an opening 2% in the valve casing 169 and into
of the relatively stationary ori?ce contact 59. The radi
a region 207 above a piston ring 299. The high pressure
ally inward blast of gas wiil then carry the are, which
gas, which is entrapped within the region 207 during the
is initially established between the annular main contact
opening movement of the ?rst dump-valve 164, will re
Q5} and the lower edge of the vertical surface 91, inwardly
tard the return closing movement of the ?rst dump-valve
through the ori?ce contact 52 so that the upper end of
164, and this action is desirable to insure that the blast
the arc terminates at the arcing terminal 64, whereas
adjacent the movable contact structures will be continued
the lower end of the arc is blown onto the arc-resisting
long enough to insure arc interruption and to prevent sub
tip portion $3 of the main movable contact ‘)5. The
sequent arc reignition until the bridging member 36 has
region '74, which is at a much lower pressure than the
separated an adequate isolating distance away from the
tank pressure, will receive the exhaust gases and will
disconnecting ?ngers S6 to insure that the ‘circuit will be
permit them to exhaust upwardly through the hollow ter
open.
In general, it will be noted that there is provided an [9 Cr minal bushing 27.
actuating means, ‘generally designated by the reference
numeral 21%) associated with each interrupting assembly
34.
The cross-arm or bridging member 36 constitutes
“Then the main current are has been extinguished in
the main current interrupting unit 415, the current through
the interrupter is forced to take the parallel path through
the impedance interrupting unit 45, which path includes
an actuating member, which initiates the opening opera
tion by opening the ?rst dump-valve member 164. In 30 the relatively stationary ori?ce contact 67 and the mov
able impedance contact 125. The circuit through the
addition, the actuating means 2% for each interrupting
impedance interrupting unit then includes the ?exible
assembly
comprises a ?rst operating means 211 for
connector 15th, terminal
of resistor assembly 54 and,
opening the movable main contact 95 of the main inter
by way of the compression springs 144, through the base
rupting unit 44 and a second operating means 212 for
casting 147 to the lower casting 139, and hence to the
causing the opening of the movable impedance contact
disconnecting ?ngers 56 to the cross-bar 36.
13.26 associated with the impedance interrupting unit 45.
However, this parallel electrical path. including the
The ?rst operating means 211 includes a ?rst piston 32
impedance
5d is soon interrupted, since, near the end
and a ?rst dump-valve means 213, the latter including
of the opening stroke of the movable main contact 95,
the ?rst dump-valve 164. The second operating means
the valve stem 113 of the second dump-valve 115 is struck
2'12 includes a second piston member 125 and a second
by the lower extension m7, and this opens the second
dump-valve means 214, which includes a second dump
dump-valve ill-,5 away from its seat 1116 thereby permit
valve 115.
ting communicaticn between the region 122 and the
From the foregoing description, it will be apparent
region 123 by way of the conduit pipe 129 and the verti
that in the closed-circuit position, illustrated in FIG. 1,
cal conduit 127. Thus, the region 123 below the second
the electrical circuit through the pole unit 33 includes
piston member 125‘, associated with the movable imped
the hollow terminal stud 32 of one terminal bushing 27,
ance contact 126, is exhausted, thereby permitting the
conducting contact foot 43, exhaust chamber 58, ori?ce
high-pressure gas within the tank 2 to force the second
plate ?ll, conducting surface 91, annular main contact 90,
piston member 125 downwardly against the upper bias
vertical side wall portion 89‘ of ?rst piston member 82,
ing action exerted by the compression spring 133. This
and through the ?ngers 88‘ to the dump-valve casting 87.
action ?rst breaks the seal between the movable blast
The circuit then extends through a plurality of support
valve 131 and its seat 132, thereby permitting a radially
feet 215, which secure the casting 37 to the bottom
inward blast of gas to take place through the ori?ce
casting 11.729. The circuit then extends through the dis
contact 67‘ and causing the extinction of the are drawn
connecting ?ngers 56 to the conducting bridging member
Because of the resistance 54 practically no current 55 thereat. This residual current are has its lower end ter
minating at the tip portion £54 of the movable imped
ance contact 126, whereas the upper end of the residual
The circuit extends through the other interrupting as
current are is blown into the hollow exhaust chamber 58
sembly 34 of the pole unit 33 in a similar manner and _
to be extinguished.
through the other hollow terminal bushing 27 to the
When the residual current are, (not shown), is ex
upper end thereof, to which a line connection is made. 60
tinguished, the circuit through the entire pole unit 33
When it is desired to open the electrical circuit passing
is interrupted, and continued downward opening travel
through the interrupter, suitable means (not shown) are
36.
?ows through the parallel impedance interrupting unit 45.
provided to actuate the pneumatic mechanism. This will
release or unlatch the mechanism to permit accelerating
springs (not shown) associated with each interrupting
of the conducting actuating member 36 will bring about
the interposition of two isolating gaps between the dis
connecting ?ngers 56 and the upper side of the conduct
assembly 34, at the outer end of the operating rod 18,
to force the several conducting bridging members 36
ing bridging member 36.
downwardly. This initial downward motion is quite
rapid, but the design of the several shock absorbers 23
is such that the initial downward opening motion is
quickly slowed down. During this initial rapid downward
opening motion of the several cross-bars 36, the latch
the hook portions 194 engaging the stop pin 1%, thereby
releasing the latch pin 158. However, rapid return
pins 158 engaging the noses 189 of the several latch
members 159 eifect opening of the several ?rst dump
In the meantime, of course, the latch 15% associated
with the ?rst dump-valve means ‘213 has been rotated by
movement of the ?rst dump-valve 164i- is not achieved
because of the previous entrapment of compressed gas
through the opening 2% and into the region 207 (FIG.
4) above the piston ring 2%. When this entrapped gas
has leaked out sufficiently, the ?rst dump-valve 164 re
valve means 213. in other words, the downward move— 75
3,023,291
closes over its seat 177, thereby sealing off the regions
202 and 203. Ordinarily, this will permit high-pressure
gas to leak from the region 217 below the valve body 168
to pass by means of the opening 218 (FIG. 4) into the
region 202. This will raise the pressure within the region
122 and permit the compression springs 96 to eilect re
closure of the movable main contact 95'. The increase
of pressure within the region 122 will act through the
of valve 164 is determined :by the velocity of the bridging
member 36, as well as by the dashpot action exerted
by the air or gas entrapped ‘within the region 207 above
the piston ring 209, as shown in FIG. 17. Upon the re
seating of the ?rst dump-valve 164, the regions 122 and
123 return to high pressure, and the valves ‘81 and 13d
together with their associated contacts move to the closed
position after all arcs are interrupted, but before the
second dump-valve 115 and through the exhaust tube 127
contacts reclose, cross-arm 36 has previously disengaged
to raise the pressure ‘within the region ‘I123, thereby per 10 disconnecting ?ngers 56, thus removing voltage from the
mitting the spring 133 to effect reclosure of the removable
entire interrupter and resistor assemblies 34.
impedance contact 126. Aswill be presently described,
During the closing operation, the pneumatic mechanism
a reclosing valve may be added to the basic interrupter
11 is actuated by the admittance of gas through the clos
whereby the impedance contact 126 may be reclosed in
ing valve 211 to force the piston 13 downwardly within
direct response to pressure increase in region 202.
the operating cylinder 12, moving the link 16 and operat
Thus, in the fully open-circuit position of the interrupter,
ing rod 15 in the closing direction charging the accelerat
both movable contact structures 49, 50 have reclosed,
ing springs. This will effect an upward movement of
and the isolating gaps between the disconnecting ?ngers
the several conducting cross-arms 36 within the tank
56 and the conducting cross-bar 56 are su?icient to hold
structures 2, bringing the bridging members 36 into en
the voltage and thereby maintain the circuit open through
gagement with the disconnecting ?ngers 56. Since this
the interrupter.
From the foregoing description, it ‘will be apparent
closing occurs in a 250‘ pounds per square inch atmos
phere, disconnecting ?ngers 56 and conducting cross
that the external dimensions and general outline of the
arm 36 are very close before an arc is established. Thus,
compressed-gas circuit interrupter are similar in size and
?rm metallic engagement is made is made before the
shape relative to that of a comparable oil breaker. The 25 crest fault current is reached.
basic interrupter includes steel tanks 2, normally in?ated
In accordance with the present invention, a reclosing
to approximately 250 pounds per square inch, pairs of
valve attachment 25% (FIGS. 3 and 6) may be provided
condenser bushings 27 associated with the tanks 2, to
on the previously described compressed gas circuit inter
gether with their associated current transformers ‘28 and
rupter to automatically provide a more rapid reclosing
potential devices 39. The interrupting assemblies 34 are
action of the movable impedance contact 126 after a
carried at the lower ends of the bushings 27, and the cross
circuit interruption operation, as previously described, so
arm 36 not only operates the interrupting assemblies 34,
that both the interrupter contact 95 and the movable
but also carries the current from one assembly 34 to the
impedance contact 126 will close within a predetermined
other. In addition, the conducting cross-bar 36 serves
minimum
time, approximately 20 cycles, thus adapting
to establish two isolating gaps in the fully open-circuit U
the circuit interrupter for operation on automatic re
position of the interrupter.
closing duty.
I
The moving parts of the main interrupter 44 consist
The reclosing valve 250 is comprised of a valve body
of the blast-valve 81, the ?nger contacts 94% and the cen
251 attached as by bolts 252 (FIG. 3) over an aperture
trally disposed arcing contact 92, all rigidly attached to
gether and biased towards the closed position by com 40 253 tapped in the previously described connector 127’,
which aperture 253 connects with the conduits 127 and
pression springs 96.
129. The valve body 251 includes a piston cavity 254
The moving parts of the resistor current interrupter
connected through a port 255 in the body 251 to com
45 consist of the blast-valve ‘131 and the arcing contact
municate with the aperture 253 when the valve body
154, both of which are biased toward the closed position
by compression spring 133.
251 is bolted to the connector 127’ as previously indi
cated.
The cross-arm 36 forms the isolating switch, as in a
The cavity 254 contains a piston 256 slidably ?tted
conventional oil breaker, and makes electrical engage
therein. The piston 256 comprises an open-ended hol~
ment with disconnecting ?ngers 56. In the closed posi<
low upper portion 257 having side walls 253, a con
tion, it also engages a latch 159, which, in turn, operates
stricted neck portion 259 aligned with the port 255 when
50
?rst dump~valve 164 through the valve stem 163.
the valve is in the extreme upper position in the cavity
During the opening of the breaker, the cross-arm 36,
254, and having a lower open-ended hollow portion 260
moving downwardly in a conventional manner, ?rst opens
dump-valve 164 by means of the latch 159. This con
nects the space 122 under the blast-valve 81 to atmospheric
having side walls 261. A port 262 on the upper end of
the body 251 provides connection between the hollow
55 upper portion 257 and the pressurized atmosphere exter
pressure through the terminal bushing 27, conservator 53
nally of the piston, the aperture being smaller than the
and the connecting tubing 175. As a result of this reduced
cavity 254 to provide a ?anged end for abutting the walls
pressure, a high pressure on the blast-valve area at 219
258 on upper end portion 257 to establish the upper
forces it open against the compression springs 96. The
terminal position of piston 256. A port 263 is provided
?rst motion unseats the valve at 73, then disengages the
in body 251 in transverse alignment with the port 255
?ngers 94, from which the arc is immediately blown upon
to provide communication between conduit 12? and the
the arcing contacts 64, 93, where it is extinguished.
pressurized atmosphere through port 263 and around
Paralleling this contact is the resistor 54 and its in
neck 259 and through port 255 when the piston 256 is
terrupter 45. As the base of the valve 81 approaches
the end of its travel, it engages valve stem 113 unseating 65 in the extreme upper end of the cavity 254 as illustrated
the valve 115 and connecting space 122 with the region
in FIG. 6. A cap 264 closes the open lower end of valve
123 through the interconnecting exhaust tubes 127, 129.
body 251 and is attached to the valve body 251 as by
By thus connecting space 123 to atmospheric pressure, or
bolts 255 (FIG. 3). A depression 266 is provided in
at least to a relatively low pressure, valve 131 is opened
the cap 264 to axially align with the longitudinal axis of
in a manner similar to Valve 811. When this valve 131 70 cavity 254 to serve as a seat for one end of a compres
opens, the resistor current is drawn in an are between
contacts 67 and 154 and is extinguished.
As the conducting cross~bar 36 moves downwardly,
the latch 159 releases latch pin 158 thereby allowing
?rst dump-valve member ‘164- to reseat. The open period
sion spring 267 situated longitudinally of the cavity 254,
which spring extends upwardly within the lower hollow
portion 265 of piston 256 to normally bias the piston
in the uppermost position within piston chamber cavity
254, as illustrated in FIG- 6. The cap 264 includes an
12
ll 1
lower extension 197, and this opens the second dump
valve 13.5 away from its seat 116 thereby permitting com
munication between the region 122 and the region 123
by way of the conduit pipe 129', connector 127’ and the
vertical conduit 127. Thus, the region 1.23 below the
second piston member 125, associated with the movable
open cavity 267 having a threaded portion around the
lip portion to receive the threaded end of a conduit 26%.
A port 269 is provided centrally of the depression 266
in the cap 264 to provide communication between the
cavity 267 and the hollow lower portion
256.
The other end of the conduit
of piston
is threadedly
impedance contact ll26, is exhausted, thereby permitting
connected to one end of a hollow plug 269 (FIGS. 3
the high pressure gas within the tank 2 to force the sec
and 4) composed of insulating material. The other end
of the hollow plug 2839 is threadedly received through
the wall of connector 172 to provide direct communi
cation between the space 262 within connector 172 and
10
the lower hollow portion are of the piston 256.
When the reclosing valve
and the attending con
duit 368 are provided on the basic compressed gas cir
cuit interrupter in the manner hereinbefore described,
the resistor circuit may be reclosed within a much
shorter time than that normally required, to thus adapt
the basic circuit interrupter for automatic reclosing cir
cuit interrupter duty, which requires that the resistor be
ond piston member 125 downwardly against the upper
biasing action exerted by the compression spring 133.
When the residual current are (not shown) is extin
guished, the circuit through the entire pole unit 33 is
interrupted, and continued downward opening travel of
the conducting actuating member 36 will bring about the
interposition of two isolating gaps between the discon
necting ?ngers es and the upper side of the conducting
bridge member 36.
in the meantime, the latch 159 associated with the
?rst dump-valve means 213 has been rotated by the hook
inserted in the circuit prior to a 20 cycle limit.
portions 194- engaging the stop pin 395, thereby releasing
The operation of the basic compressed gas circuit
interrupter, with the reclosing valve
and the con
the latch pin 158. However, rapid return movement of
the ?rst dump-valve 164 is not achieved because of the
previous entrapment of compressed gas through the open
ing 2% and into the region 2527 (FIG. 4) above the piston
ring 269. When this entrapped gas has leaked sufficiently,
duit Z68 attached will now be described.
When it is desired to open the electrical circuit pass
ing through the interrupter, suitable means (not shown)
are provided to actuate a pneumatic mechanism (not
shown). This will release or unlatch the pneumatic
mechanism to permit accelerating springs associated with
the ?rst dump-valve 1-64 will reclose over its seat 177,
thereby sealing oil the regions 2&2 and 293. This will
permit high pressure gas to leak from the region 217
below the valve body 168 to pass by means of the opening
each interrupting assembly
to operate the rod 18 to
force the several conducting bridging members 3:? down 30 215 (FIG. 4) into the region 2%. This will raise the
pressure within the region 122 and permit the compression
wardly. During this initial rapid downward opening
springs 96 to effect reclosure of the movable main con
motion of the several cross-bars as, the latch pins 158
engaging the noses
of the several latch members
15? e?fect opening of the several ?rst dump-valve means
tact 95.
At the same time, the increased pressure in
213. in other words, the downward movement of the
latch member\) 159 effects opening of the ?rst dump-valve
region 2% extends through conduit 26?» of the present
invention to the lower hollow portion 260 of the piston
256 in the reclosing valve 253 of the present invention
1643 to open the connection between the regions 2%
to equalize the downward pressure on the upper hollow
(FIG. 4) and the region 2%, which communicates di
portion 257 of piston 2S6, whereupon the compressed
rectly with the region 122, on the lower side of the ?rst
biasing spring 267 operates to return the piston 256 to
piston 82., and which also communicates directly through 40 the upper position as illustrated, thus opening the ports
the added conduit
to the lower hollow portion 266
of piston 256 in reclosing valve 256 of the present in
vention. Because high pressure xists within the region
77 within the tank structure 2, and because there is now
a low pressure within the region lli‘, , the ?rst piston
member
will be forced downwardly to open the
movable blast-valve Ell away from its cooperating blast
valve seat 78 providing an inward blast of gas from the
pressurized area 77 to extinguish the arc in the manner
previously described.
Because high pressure exists in
the area surrounding reclosing valve 25% applying pres
sure through port 262 against the inside of upper hollow
portion 257 of the piston ass, the low pressure within
region 2&2 arising out of operation of dump-valve 164
263 and 255. The high pressure condition of the at
mosphere externally of the reclosing valve 256 now ex
tends through ports 263, 255, 253, connector 127' and
conduit 127 to immediately raise the pressure within re
gion 123, thereby permitting spring 133 to reclose mov
able impedance contact 1.26.
Thus, the presence of reclosing valve 250 and its con
duit 268 provides rapid enclosing or" the movable im
pedance contact 126 in direct response to reclosing of
the main dump-valve 164, whereas, as previously de
scribed in the description of the basic compressed gas
interrupter, the movable impedance contact 126 could
not reclose until after the movable main contact was
extends through conduit 268 to the lower hollow portion 55 closed by the dump-valve 115.
When an automatic reclosing mechanism (not shown)
260 of piston 25d providing a pressure diiierential which
actuates the operating rod 18 in the closing direction,
forces the piston 25o downwardly to compress the spring
the conducting cross-arms 36 are moved upwardly within
267 and close the ports 2:53 and 253} to isolate the con
the tank 2, bringing the bridging members 36 into en
duits 127 and 325‘ from the pressurized area through
60 gagement with the ?ngers 56.
these ports.
From the foregoing it is apparent that this invention
Vhen the main current are has been extinguished in
provides a simple unitary reclosing valve attachment
the main current interrupting unit
the current through
the interrupter is forced to take the parallel path through
which, when added to the basic compressed gas circuit in
the impedance interrupting unit 45, which path includes
terrupter as described, adapts the circuit interrupter for
the relatively stationary ori?ce contact 67 and the mov
operation on automatic reclosing duty. The attachment
able impedance contact
The circuit through the
is simple and may be readily added to the basic circuit
impedance interrupting unit then includes the ?exible
connector 15%, terminal 14% of resistor assembly 54- and,
by way of the compression springs 114d, through the base
interrupter in the field, the only required modi?cation of
the basic interrupter being the addition of three taps in
the connector 127’ for the port 253, the addition of two
casting 147 to the lower casting 139, and hence to the 70 bolts 252, and the addition of a tap in connector 172
disconnecting ?ngers 55 to the cross-bar 3-5.
to receive the plug 2% for the added conduit 268.
However, this parallel electrical path including the im
Although there is shown and described speci?c struc
pedance 5d is soon interrupted, since, near the end of the
tures, it is to be understood that changes and modi?ca
opening stroke of the movable main contact 95, the valve
stem 113 of the second dump-valve 115 is struck by the 75 tions therein may be readily made by those skilled in the
13‘
3,023,291
art without departing from the spirit and scope of the
present invention.
We claim as our invention:
1. A compressed gas circuit interrupter including means
de?ning an enclosure containing pressurized gas, an in
terrupting assembly disposed interiorly within the en
closure and including a main current interrupter unit and
an impedance interrupting unit connected in electrical
14
therewith, ?rst operating means including a piston mov
able with said movable main contact and also including
?rst dumping means for exhausting gas from the back
side of said piston to effect opening movement of said
movable main contact to force current to ?ow through
the parallel disposed impedance interrupting unit, second
operating means including a piston movable with said
movable impedance contact and also including second
parallel with each other, said main current interrupting
dumping means for exhausting the gas from in back of
unit having a movable main contact associated therewith, 10 said last-mentioned piston to effect opening movement of
?rst operating means including a piston movable with said
said movable impedance contact, means responsive to
movable main contact and also including ?rst dumping
operation of the ?rst operating means for actuating said
means for exhausing gas from the back side of said piston
second operating means subsequent to the actuation of
to effect opening movement of said movable main con
said ?rst operating means to effect opening movement of
tact to force current to ?ow through the parallel disposed 15 the impedance contact only after the opening of the mov
impedance interrupting unit, second operating means in
able main contact, a port connecting the gas chamber to
cluding a piston movable with said movable impedance
the back side of the second operating means to effect re
contact and also including second dumping means for
closing of the impedance contacts, reclosing valve means
exhausing the gas from in back of said last-mentioned
operable in response to an exhaust operation of the ?rst
piston to effect opening movement of said movable im
dumping means to close the port and operable in re
pedance contact, means responsive to operation of the
sponse to reclosing operation of the main dumping means
?rst operating means for actuating said second operating
to open the port.
means subsequent to the actuation of said ?rst operating
4. A compressed gas circuit interrupter including an
means to effect opening movement of the impedance
enclosure containing pressurized gas, an interrupter as
contact only after the opening of the movable main con 25 sembly disposed within the enclosure and including a
tact, and reclosing valve means operable in response to
main interrupter unit and an impedance interrupting unit
reclosing of the ?rst dumping means to directly connect
connected in parallel, each unit having a relatively mov
the back of the movable impedance piston to the pres
able contact mechanism and an operating means includ
surized gas enclosure to- effect rapid reclosing of the
ing a piston for e?‘ecting opening and closing movement
movable impedance contact.
30 of the contact mechanism, ?rst dumping means for ex
2. A compressed gas circuit interrupter including
hausting gas from the back side of said main interrupter
means de?ning an enclosure containing pressurized gas,
piston to effect opening movement of said movable main
an interrupting assembly disposed interiorly within the
contact, second dumping means for exhausting gas from
enclosure and including a main current interrupter unit
in back of the impedance unit piston to effect opening
and an impedance interrupting unit connected in electrical
movement of said movable impedance contact, means
parallel with each other, said main current interrupting
responsive to operation of said ?rst operating means for
unit having a movable main contact associated therewith,
effecting operation of the impedance interrupter operat
?rst operating means including a piston movable with said
ing means subsequent to the operation of the main inter
movable main contact and also including ?rst dumping
rupting operating means, a switch operable to be opened
means for exhausting gas from the back side of said pis
and closed in response to operation of an automatic re
ton to effect opening movement of said movable main
closing mechanism, said switch means ‘having separable
contact to force current to flow through the parallel dis
contacts and connected in series with the parallel con
posed impedance interrupting unit, second operating
nected main interrupter and impedance interrupter, means
means including a piston movable with said movable im
releasably connecting the switch to open the ?rst dump
pedance contact and also including second dumping 45 ing means during initial opening movement of the switch
means for exhausting the gas from in back of said last
and including means for releasing the connecting means
rnentioned piston to e?ect opening movement of said
subsequent to the opening of the interrupter contacts and
movable impedance contact, means responsive to opera
the impedance contacts to effect reclosing of the dump
tion of the ?rst operating means for actuating said second
ing means, and reclosing valve means operable in re
operating means subsequent to the actuation of said ?rst
sponse to reclosing of the ?rst dumping means to directly
operating means to effect opening movement of the im
connect the back of the movable impedance piston to the
pedance contact only after the opening of the movable
pressurized enclosure to effect rapid reclosing of the mov
main contact, a channel directly connecting the back of
able impedance contact.
°
the movable impedance piston to the pressurized gas en
5. In an automatic reclosing circuit breaker system:
closure, a reclosing valve in the pressurized enclosure and
a main circuit interrupter unit and an impedance interrup
including a piston operable to open and close the chan
ter unit connected in parallel; contact means for each
nel, and conduit means connecting the back of the re
interrupter unit, a switch operable to be opened and
closing valve piston to said ?rst dumping means whereby
closed in response to operation of an automatic recloser
an opening operation of the ?rst dumping means ex
mechanism and connected in series with said parallel con
hausts gas from in back of the reclosing piston to effect 60 nected interrupter means; interrupter operating means
closing of the channel to maintain a normal opening
responsive to the initial portion of an opening operation
sequence of the main interrupter contact followed by
of said switch to open the main interrupter contacts; means
opening of the impedance contact, and whereby reclos
responsive to opening of the main interrupter contacts
ing of the ?rst dumping means etfects restoration of
to subsequently open the impedance interrupter contacts;
gas pressure in back of the reclosing valve piston for open 65 means for automatically closing the main interrupter con
ing the channel to effect restoration of gas pressure in
tacts and the impedance interrupter contacts independent
back of the movable impedance piston for rapidly reclos
ing the impedance contacts.
3. A compressed gas circuit interrupter including
ly and substantially simultaneously after the switch is
opened to effect reinsertion of the impedance interrupter
unit in circuit with the main interrupter unit before the
means de?ning an enclosure containing pressurized gas, 70 switch is reclosed by a reclosing operation of the auto
an interrupting assembly disposed interiorly within the
matic recloser apparatus.
6. In an automatic reclosing circuit breaker system:
a main circuit interrupter unit and an impedance inter
trical parallel with each other, said main current inter
rupter unit connected in parallel; each interrupter unit
rupting unit having a movable main contact associated 75 having contacts and means for opening and closing the
enclosure and including a main current interrupter unit
and an impedance interrupting unit connected in elec
5,023,291
reclosing operation of the impedance operating means
contacts; a switch operable to be opened and closed in
response to the operation of an automatic reclosing mecha
whereby the main contacts and the impedance contacts
reclose substantially simultaneously to reinsert the im
pedance unit in circuit with the main interrupter unit be
fore the switch is reclosed by a reclosing operation of
the automatic reoloser mechanism.
nism and connected in series with said parallel connected
interrupter means; main operating means actuated in re
sponse to the initial portion of a switch opening opera
tion to effect and maintain a contact opening operation
of the main contact operating means until the main op
erating means is deactuated; means responsive to an open
ing operation of the main contacts to effect a contact
opening operation or" the impedance contact operating
References Cited in the ?le of this patent
UNITED STATES PATENTS
10
means subsequent to the opening operation of the main
contacts but before the switch is opened and to main
tain the opening operation until the main contacts re
close; means operable to deactuate the main operating
means after the switch is opened; and means responsive 15
to deactuation of the main operating means to override
the means effecting and maintaining operation of the im
pedance contact operating means to effect an immediate
2,470,628
Ludwig _____________ __ May 17, 1949
2,903,788
Forwald ____________ .__ Oct. 13, 1959
FOREIGN PATENTS
582,599
151,019
1,063,682
Great Britain _________ __ Nov. 21, 1946
Sweden ______________ __ Aug. 9, 1955
Germany ____________ __ Aug. 20, 1959
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