US3761735A

US3761735A - Power apparatus for operating electric disconnect switches

Info

Publication number: US3761735A
Application number: US00269467A
Authority: US
Inventors: J Turner; F Diener
Original assignee: Turner Electric Corp
Current assignee: Turner Electric Corp
Priority date: 1972-07-06
Filing date: 1972-07-06
Publication date: 1973-09-25
Anticipated expiration: 1990-09-25
Also published as: CA975080A

Abstract

Power apparatus for operating electric transmission line disconnect switches includes an hydraulic motor normally mechanically coupled to the switch, an electrically driven hydraulic pump, an hydraulic pressure accumulator to provide hydraulic pressure in the event of electric power failure, solenoid-actuated valves controlling the admission of hydraulic pressure to the hydraulic motor, and selectively locally or remotely controlled relays for controlling the solenoid-actuated hydraulic motor control valves. Means is provided for uncoupling the switch from the hydraulic actuator to permit manual operation of the switch or remote testing of the power apparatus.

Description

United States Patent [1 Turner et al.

[ POWER APPARATUS FOR OPERATING ELECTRIC DISCONNECT SWITCHES [75] Inventors: John L. Turner; Fred L. Diener, both of Fairview Heights, Ill.

[73] Assignee: Turner Electric Corporation, East St.

Louis, Ill.

[22] Filed: July 6, 1972 [21] Appl. No.: 269,467

[521 U.S. Cl 307/112, ZOO/48 P [51] .Int. Cl. H01h 3 1/00 [58] Field of Search 307/112; 200/48 P, '200/48 R; 335/68 [56] References Cited UNITED STATES PATENTS 3,043,924 8/1962 Johnson 200/48 R 3,126,756 3/1964 Bertling 335/68 X Sept. 25, 1973 Primary Examiner-Robert K. Schaefer Assistant Examiner-M. Ginsburg Attorney-F. Travers Burgess et a].

[ 5 7 ABSTRACT Power apparatus for operating electric transmission line disconnect switches includes an hydraulic motor normally mechanically coupled to the switch, an electrically driven hydraulic pump, an hydraulic pressure accumulator to provide hydraulic pressure in the event of electric power failure, solenoid-actuatedvalves controlling the admission of hydraulic pressure to the hydraulic motor, and selectively locally or remotely controlled relays for controlling the solenoid-actuated hydraulic motor control valves. Means is provided for uncoupling the switch from the hydraulic actuator to permit manual operation of the switch or remote testing of the power apparatus.

35 Claims, 11 Drawing Figures PATENTEB SEP25 I973 SHEET '4 [1F 7 1 Powsn APPARATUS FOR (Immune ELECTRIC DISCONNECT SWITCHES FIELD OF THE INVENTION SUMMARY OF THE INVENTION Among the objects and advantages of the invention, the following are significant: Y

Hydraulic pressure for operating the switch-actuating hydraulic motors is always available, even though the electric pump motor is inoperative.

Programmed. speed control is provided for both opening and closing the switches, and is adjustable in the field. Provision is made for higher switch blade speed during the final portion of the closing cycle so as to minimize arcing onclosure. This blade velocity is also important should the switch blade be closed on a fault. The switch blades would then be well into their respective contacts where the switch momentary rating is at its best and the over current relay, at the OCR breaker source would interrupt the line without damaging any of the switch blades. Blade velocity can be field adjusted to meet the conditions of any airbreaker switch without damage.

The actuator hydraulic circuits are at zero pressure while not in operation.

When manual control of the switches is desired, decoupling the switches from the hydraulic actuators is simple, direct effective manual operation without cranks or pump is provided, the operating lever is at a comfortable and convenient height and is arranged not to hang up on locking tangs. Both d cou ling and manual operation may be effected without removing any covers from housings, the handle may be padlocked in either open or closed positions and need not be removed during hydraulic operation, but remains in full sight.

The operating rod is arranged to accommodate to thermal contraction and expansion to avoid unnecessary weight on the actuator assembly and consequent increase in torque necessary for, manual operation.

The hydraulic actuating circuits and electrical control circuits are wholly independent on the AC line voltage. I v

The control system will not initiate opening or closing movement unless hydraulic pressure sufficient to complete the movements is present.

The control circuit is interlocked to insure operation of only one air break switch at a time.

Each actuator mounts sensing 'cams which sense the actual position of the switch and thereby insures full operation, so that the air break switch may not be stopped in partially open or'closed position.

During travel time of an air break switch from closed to open position, or vice versa, local and remote operation is blocked.

Operating. circuits of an air break switch are automatically disabled when the switch has been fully opened, to prevent initiation of another opening operation. I

The actual position of the air break switch is sensed to terminate closing and opening movements, rather than relying on sensing of excessive pressure buildups in the hydraulic circuit.

A push and hold switch for local operation assures that the system will return to remote control operation when the local operation is completed, making it unnecessary for the man performing the local operation to return the system manually to remote control.

Maintenance is facilitated by the fact that the hydraulic actuator .can be removed without affecting manual operation and locking, easy access to the parts, absence of gear trains, and few moving parts.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view of an air break switch installation incorporating a switch operator constructed in accordance with the invention.

FIG. 2 is a side elevation view of the installation illustrated in FIG. 1.

FIG. 3 is a front elevation view of the hydraulic actuator with cover removed.

FIG. 4 is a horizontal sectional view along line 44 of FIG. 3.

FIG. 5 is a side view of the manual operating lever showing manual operating and uncoupled locking positions.

FIG. 6 is a top view of the manual operating lever, taken from line 6-6 of FIG. 5.

FIG. 7 is a front elevation view of the control cabinet with outer door open.

FIG. 8 is a front elevation view of the control cabinet with the control panel opened.

DETAILED DESCRIPTION The numeral 1 indicates a pole, mounting on suitable brackets 3 three three-way air break disconnect switches "each comprising three

rotatable insulators

5a, 5b and 50, three switch blades 7a, 7b and 7c secured respectively to insulators 5a, 5b and 5c for rotation there-. with, and a central fixed insulator 9 supporting switch jaws 11a, 11b and lie. Each switch blade 7a, 7b or is selectively swingable into and out of engagement with jaws 11a, 11b or 1-10 by rotation of the

respective insulator

5a, 5b or 50 about its axis. To permit operation of the switches from the ground,

vertical operating shafts

13a, 13b and 130 are journaled in suitable brackets 15 on pole l, and are connected by

suitable linkages

17a, 17b and 17c to rotatable insulators 5a, 5b and 5c of the three switches so that, upon rotation of

shafts

13a, 13b or 130 in one direction, the respective switch blades 7a, 7b or 70 will be swung approximately from the closed position shown in FIG. 1 to an open position, and upon counterclockwise rotation of

shafts

13a, 13b or 130, blades 7a, 7b or 70 will be returned to the closed position.

For rotating

shafts

13a, 13b and 13c between their switch open and switch closed positions, separate hydraulic actuators, generally indicated at 19a, 19b and 19c, are mounted on the lower end of pole 1. Since all the hydraulic actuators are identical, only actuator 19a will be described in detail, it being understood that similar numbers, followed by the letters b and c refer to corresponding parts of the other actuators. Hydraulic actuator 19a comprises a housing 21a secured to the pole. Within housing 21a, an oscillating hydraulic motor 250 is rigidly mounted and its output shaft 29a is vertical and extends upwardly through an aperture in the housing top wall 31a for selective coupling to shaft 130.

At its lower end, shaft 13a is connected by a universal joint 33a to a coupling member 35a which consists of a sleeve 37a rotatably and axially slidably receiving the upper end of hydraulic motor shaft 29a.

A handle mount comprising a bifurcated radial handle-bracket 39a, positioned between radial upper and lower locking arms 41a and 43a, issecured to sleeve 37a by U-bolts 45a or other secure clamping means. A handle comprising a section of pipe 47a has an end fitting 49a pivotally secured at 510 to the outer end of handle bracket 39a on an axis transverse of the latter. Fitting 49a is bifurcated at 53a with its tines 54a adapted to embrace upper and lower locking arms 41a and 430 respectively when the

handle

47a, 49a is swung upwardly or downwardly about pivot 51a, and arms 41a and 43a are perforated at their outer ends at 420 and 44a to permit locking of the handle in the selected position. t

From the foregoing, it will be evident that sleeve 37a and shaft 130 will rotate in unison with

handle

47a, 49a

by virtue of the rigid securement of handle mount 39a,

41a, 43a to sleeve 37a. To provide for the transmission of rotational movements from hydraulic motor 25a to shaft 13a, sleeve 37a and motor shaft 29a are formed with radially alignable apertures or

slots

55a, 57a above I handle

mount

39a, 41a, 43a and a projection 59a extending radially upwardly from handle end fitting 49a is adapted to pass through sleeve slot 55a and into motor shaft slot 57a when

handle

47a, 49a is swung to its uppermost position generally parallel'with shaft 13a, thereby preventing relative rotation between motor shaft 290 and sleeve 37a and causing the direct transmission of rotary movements from hydraulic motor 25a to shaft 130.

Thus, when it is desired to provide hydraulic actuation for disconnect switch 70,

arm

47a, 49a issecured in its uppermost position (FIG. 3) with projection 59a projecting into

slots

55a and 57a. If manual operation is desired,

arm

47a, 49a is swung about its pivot 51a to a convenient generally horizontal position. Slot 57a is vertically elongated as best seen in FIG. to accommodate vertical movement of sleeve 370 on shaft 29a and thereby allow for expansion and contraction of shah4 13a without application of excessive axial forces to hydraulic motor shaft 29a and possible damage to the motor.

For locking the handle in any desired switch open or closed position, a pair of stop plates 610 are adjustably secured to top wall 310 of the hydraulic actuator housing, and are formed with radially slotted radial projections 63a, into which a radial rib 65a on handle end fitting 49a is selectively receivable when the

handle

47a, 49a is swung downwardly. The handle maY be retained in the upturned hydraulic actuator position, or in either of the manual locked positions by padlocks in

perforations

420 or 44a of handle locking tangs 41a and 43a respectively,

A source of hydraulic pressure and electrical means for controlling its admission to hydraulic motors a, 25b and 25c (see FIG. 9) are located in a cabinet 67 mounted on the lower end of an adjoining stub pole 69.

Cabinet 67 has a vertically hinged door 71, immediately within which is a similarly vertically hinged con- 4 trol panel 73, enclosing the upper portion of the cabinet.

The cabinet contains reservoir of hydraulic fluid, which is connected by conduit 77 to a hydraulic pump 79 driven by electric motor 81. Pump 79 is connected by a conduit-83 containing a check valve 85 to hydraulic accumulator 87, which contains a quantity of inert gas, such as nitrogen, under predetermined pressure so as to maintain the fluid in line 83 posterior to check valve 85 under pressure even if pump 79 is rendered inoperative due to power failure or other causes.

From accumulator 87, conduit 83 leads to a normally closed shut-off valve 88, controlled by a solenoid 89 and thence to velocity control valve 90 which has a normally restricted variable orifice 86 controlled by a solenoid 91 so as to be enlarged when the solenoid is energized. A conduit 92 containing a manually controlled fast speed adjustment valve 94 leads from valve 90 to

directional valves

93a, 93b and 93c. A return line 95 leads from

directional valves

93a, 93b, 930 to reservoir 75. Each

directional valve

93a, 93b, 930 has a slider 101a, l01b or 10lc formed with crossed passages 92a and parallel passages 94a alignable respectively with the valve parts, and a pair of

solenoids

96a and 98a are connected to slider 1010 to move it to the respective switch-open and switch-closed positions. Sliders l0lb and l0lc are similar to slider 101a, with corresponding passages 92b and 920, parallel passages 94b and 940, and solenoids 96b, 96c, 98b and 98c.

Hoses

97a, 97b and 97c and 99a, 99b and 990 connect

directional valves

93a, 93b, 93c with opposite sides respectively of hydraulic motors 25a, 25b and 250. Between control cabinet 67 and the respective hydraulic actuator cabinets,

hoses

97a and 99a, 97b and 99b and 97c and 990 respectively, are carried in

flexible conduits

100a, 10% and 100a.

For energizing pump motor 81 when pressure in the system declines below a predetermined value, a pressure take-off conduit 103 connects conduit 83, intermediate check valve 85 and accumulator 87, with a pressure-responsive switch 105 and pressure gauge 107, and has a drain extension 109, including a normally closed manual shut-ofi valve 111, leading to reservoir 75.

With the hydraulic systems described above, it will be evident that when solenoid 89 is energized to open valve 88, pressurized fluid will flow through the restricted orifice of valve 90 and conduit 92 to

directional valves

93a,93b and 930, and when any of the latter is opened, and its desired

outlet conduits

97a ,97b or 97c, or 99a, 99b or 990 connected to

hydraulic motor

25a, 25b or 25c, the fluid will flow to the desired side of the respective oscillating hydraulic motor 25a, 25b or 250, to rotate the respective motor shaft in the direction necessary for swinging the respective switch blade 7a, 7b or 70 toward the desired open or closed position, and during the latter part of the closing cycle, e.g., the final 30 per cent, when solenoid 91 is energized to fully open the orifice of valve 90, the latter will increase the velocity of the fluid through conduit 92, correspondingly increasing the closing velocity of the hydraulic motor 25a, 25b or 250 causing the switch to close fast, thereby minimizing arcing time and eliminating a circuit breaker operation.

The electrical control circuit for the electric motor, the power and directional switches and the solenoids of the hydraulic system are shown schematically in FIGS. A and 10B. I

The electrical system comprises a low voltage, e.g.,

direct current 24 V, control and pump motor circuit which is connected by wire 135 to pump motor 81 and a wire 129 connects wire 121 to contacts 105U of hydraulic pressure-responsive switch 105, which is calibrated to open when hydraulic pressure rises above 1,400 p.s.i. and to close when pressure falls below 1,300 p.s.i. in the hydraulic circuit illustrated in FIG. 9. Wire 12S connects pressure switch contacts 105U to the motor relay coil 127, which is accordingly ener gized whenever pressure switch 105 isclosed, so that when pressure switch contacts 105U energize motor relay coil 127, the latter closes motor relay armature 133 to complete the circuit to motor 81 which operates until hydraulic pressure reaches 1,400 p.s.i. When this occurs, pressure switch contact 105U opens, deenergizing motor relay coil 127, which permits motOr relay armature 133 to open, thus deenergizing pump motor 81. Thus pressure in the hydraulicsystem is maintained constantly at approximately 1,400 p.s.i.

Motor relay coil 127 and pump motor 81 are connected respectively by

wires

137 and 139 to a common negative wire 141 to complete their respective circuits.

For remotely or locally controlling power valve89 and

directional valves

93a,93b and 93, a command circuit is provided in which a wire 143 connects low voltage positive wire 115 to a terminal 144, from which a wire 145 leads to contacts 105L of pressure switch 105 which closes when pressure rises to 1,400 p.s.i. and opens when pressure declines below 1,350 p.s.i., thus preventing energization of the control circuits except when the pressure is within this range. This effecitvely prevents initiation of any opening or closing movement of the air break disconnect switches while any other movement is taking place. Pressure switch contacts 105L, are connected by a wire to contact 153 of a push-type double-pole double-throw switch l55.-The other corresponding contact 157 of switch 155 is connected by wire 159 to terminals 161a, 161b and 16k through which connections are made to circuits 163a, 163b and 163C respectively, including remotely'controlled relays 165a, 165b and 1650, for remotely controlling respectively air break switches 7a, 7b and 7c.

Push-type switch 155 includes another pair of

contacts

169 and 171 and wire 151 is connected to contact 169 as well as contact 153. The switch has a plunger 173 equipped with a button and a pair of spaced contact members 177 and 179 and is resiliently biased so that the latter normally conductively engages

contacts

153 and 157 and is disengaged from

contacts

169 and 171, thus leaving the remote control wire 159 normally connected to the 24 V power source.

Normally open push-type switch contact 171 is connected in parallel by wire 181 to the single pole terminals 183a, 1831: and 183c of manually operable singlepole double-throw switches 185a, 1851: and 185:, for manually controlling switch blades 7a, 7b and 7c.

From the foregoing it will be evident that normally the system will be set for remote control, and that local operation can take place only while the operator holds button 175 of switch 155 depressed to release contactor 177 from:

contacts

153 and 157 and to cause contactor 179 to engage contacts 169 and-171.

The individual control circuits for each of the air break switches are identical, and accordingly only that for switch 7a will be described in detail, with the understanding that the same reference numerals followed respectively by the letters a, b, or 0 refer to corresponding elements of all three circuits.

Manual operator single-pole double-throw switch 185a has opening and closing contacts 195a and 197a with

respective terminals

199a and 2010.

From

terminals

199a and 201a,

wires

207a and 209a lead respectively to opening and

closing circuit terminals

211a and 213a, from which wires 223a and 225a lead to cam switches 227a and 2290 (FIG. 10B) respectively. For remotely controlling the switch movements by radio or carrier circuit, relays 165a may include opening and

closing contacts

187a and 189a, connected by wires 188a and 190a to terminals 191a and 193a in wires 223a and 225a. Cam switches 227a and 229a are actuated by

cams

231a and 233a mounted on hydraulic motor output shaft 290 so that their positions reflect the actual position of air break switch 7a. CAm 2310 is arranged to maintain its switch 227a closed as long as air break switch 7a is closed and to open switch 227a whenever air break switch 7a is open whereby to insure that the opening circuit for switch 7a cannot be energized while switch 7a is open. Correspondingly, cam 233a is arranged so that its switch 229a is open whenever air break switch 7a is closed so that the closing circuit cannot be energized when air break switch is closed; conversely, cam 233a maintains its switch 229a closed when air break switch 7a is openso as to permit the closing circuit-to be energized when air break switch 7a is open.

The fixed

contacts

235a and 237a of

cam switches

227a and 229a are connected by wires 239a and 241a respectively to terminals 243a and 245a and thence by wires 244a and 246a to directional valve opening and

closing solenoids

96a and 98a respectively, which are connected respectively by

wires

247a, 249a to a common negative wire 251. The latter is connected via terminal 253 to common negative lead 141, thus completing the circuits through

solenoids

96a and 98a when they are selectively energized either by manual operator switches 185a or remote control relays 165a. To maintain the

directional valve solenoids

96a and 98a energized throughout the respective opening or closing movements of the air break switches, holding means are provided comprising opening directional relay coil 219a and closing directional relay coil 221a connected by wires 255a and 257a to terminals 243a and 245a and their respective armature contactors 259a and 261a (FIG. 10A) are connected by wires 263, and 143 to the power source and by their respective fixed contacts 215a and 217a to wires 223a and 225a leading to

solenoids

96a and 98a and relay coils 219a and 223a.

With this arrangement upon energization of the respective opening, or

closing solenoids

96a or 98a, either by manual operator switch 185a or remote control relay a the corresponding relay coils 21911 or 221a will be energized thereby closing the corresponding armature 2590 or 2610 and the power source will be connected via

wires

143, 145 and 263 and the appropriate armatures 259a or 2610, wires 223a or 2250, cam

switch 2270 or 229a, and wires 239a or 241a to the

respective relay coils

219a and 221a, keeping them energized and their armature contactors closed and to

directional valve solenoids

96a or 98a keeping the latter energized and the corresponding valves open after the momentarily closed local switches 185a or the remote control relays 165a have returned to their open positions. Open and

close relay coils

219a, 221a, 219b, 221b and 2190, 2210 are connected by a common negative wire 265 to common negative lead 141, thus completing the circuits through the open and close relays.

For opening shut-off valve 88 so as to permit hydraulic fluid to pass from accumulator 87 through conduit 92 to the respective

directional valves

93a, 93b or 930,

. a wire 267 is connected via terminal 144 to positive lead 143 and at its other end is connected in parallel to

armatures

269a, 271a,- 269b, 271b and 2690, 2710 off opening and closing relays of each of the switch control circuits and the corresponding fixed

contacts

273a, 275a, 273b, 275b, and'2730, 2750 are connected by wire 2 77to the one terminal of shut-off valve relay coil 279, the other terminal of which'is conected by wire 281 to opening and closing relay coils return wire 265. Armature 283 of the shut-off valve relay is connected to wire 267 described above, the fixed contact 285 of the shut-off relay armature 283 being connected by wire 287 to shut-off valve solenoid 89, the negative side of which is connected by wire 291 to return wire 141.

With the shut-off valve relay circuit just described, upon closure of either of the opening or closing

relay armatures

269a or 271a, relay coil 279 will be energized, thereby closing its armature 283 and energizing shut-off valve solenoid 89 to open the'shut-off valve (FIG. 9) and permit pressurized fluid to flow at the relatively low velocity permitted by the restricted orifice of velocity control valve 90 through the selected open or closed side of the directional valves and therefrom to the appropriate side of hydraulic motors 25a, 25b or 250 to initiate movement of the corresponding air break disconnect switch 7a, 7b or 70 to the selected open or closed position.

To insure that the control circuits will be broken in case of malfunction, a time delay relay coil 293 is connected by wires 295 and 297 in parallel with shut-off relay'coil 279, and normally closed armature 299 of the time delay relay is connected into wire 263 which supplies current to each of the holding circuits, the time delay relay being calibrated so that holding circuit 263 (FIG. 10A) supply wire is deenergized a predetermined period, e.g., seconds, in excess of the normal time necessary to open or close an air break switch after any of the control circuits have been energized, thus prevenging continuous flow of current through the control circuits. I

With the arrangement described thus far, closing movements of each of the air break switches 7a, 7b or 70 would be initiated at slow speed as governed by the low velocity of fluid passed by the variably restricted orifice of close fast valve 90. To minimize arcing time and eliminate a breaker operation on the air break switches, means is provided for accelerating the closure of the air break switches during approximately the final 30 percent of their closure movement. To this end, a third cam 301a, 301b or 3010 is mounted on the respective hydraulic

motor output shaft

29a,29b and 290 and the respective cam actuated switches 3030, 303b and 3030 are connected respectively by wires 305a,

spectively supply closing relay coils 221a, 221b and 2210 and the fixed

contacts

307a, 307b and 3070 are connected by a common wire 309 to the positive terminal of velocity control relay coil 311, the negative terminal of which is grounded by wire 265. The armature 313 of velocity control relay coil 311 is connected to a line 315 which in turn is connected to positive lead 143 and the fixed contactor 317 of the velocity control relay is connected by a wire 319 to one terminal of velocity control valve solenoid 91, the other terminal of which is connected to negative lead 141 by wire 321. Cams 301a, 301b and 3010 and the corresponding switches 303a, 303b 3030 are calibrated such that the switches close when the corresponding air break switches have completed approximately half of their closing cycles, thereby energizing the velocity control.

valve solenoids 91 to fully open the velocity control valves and thereby increase the velocity of hydraulic fluid through passage 92 to the appropriate

directional valves

93a, 93b or 93c and thence to the appropriate hydraulic motors 25a, 25b or 250 where the increased velocity of the fluid causes an accelerated closure movement of the hydraulic motor. and of the corresponding air break switch 7a, 7b or 7c through approximately the final 30 percent of its closure, thus preventing damaging arcing.

For the assistance of persons manually operating or inspecting the equipment,

green signal lights

3230, 323b and 3230 are provided in the control cabinet to indicate that the respective switches are open, and

red lights

325a, 325b and 3250 are similarly provided to indicate that the corresponding air break switches are closed. For energizing

lights

323a, 323b and 3230 and 3250, 32511 and 3250, cams 327a, 327b and 3270 are mounted on the corresponding hydraulic

motor output shafts

29a, 29b and 290 and are provided with singlepole double-throw switches 329a, 329b and 3290 respectively, all connected by positive wire 331 to positive lead 143. One of the fixed contacts 333a, 333b and 3330 of each switch is connected by wire 335a, 335b and 3350 to the corresponding

green lights

323a, 323b or 3230 while the other fixed contacts 337a, 33b or 3370 are connected by wires 339a, 339b and 3390 to the corresponding red lights, all of which are grounded through wire 341 connected to negative lead 141. Cams 3270, 327b, 3270 and their corresponding switches are calibrated so that when their corresponding air break switches 7a, 7b or 70 are opened, cam switches 329a, 329b and 3290 will be in contact respectively with fixed contacts 3330, 333b and 3330 to energize the corresponding green lights, whereas when the corresponding air break switches are closed the cam switch 329a, 329b or 3290 will be in contact respectively with their fixed contacts 337a, 3371: or 3370 to energize the corresponding red lights.

To prevent useless energization of the lights when the cabinet door is closed, and thereby increase the life of the lights, wire 331 includes a normally open doorcontrolled switch 343 which prevents the light from being illuminated when the door is closed, and which is closed by opening movement of the door to energize the light circuits.

If desired, as an additional means to prevent energization of any of the command circuits while air break switch movements are being made, wire leading to terminal 169 of local/remote control push button switch 175 may include a normally closed interlock switch 339 controlled by shut-off valve relay 279 so as to be opened when the latter is energized as described above and thereby isolate the control circuits from further commands, either local via switches 185a, 185b and 185C, or remote via radio or carrier circuit through wire 163, during operation of any of the air break switches.

Operation of the device is as follows: Upon receipt of an operational command from one of the remotely controlledrelays, e.g., 1650 moved to the open position with its armature in engagement with contact 187a, current flows from the source through

wires

143 and 145, pressure switch control 1051s, interlock switch 339 (if provided) and contact 153, push-type switch move the directional valve slider 101a so that crossed passages 920 are in registry with the valve ports, causing fluid to flow through conduit 99a into the switch opening side of hydraulic motor 250.

Upon energization of opening relay coil 219a it closes contactors 259a and 269a, causing current to flow through wire 263 and time delay relay armature 299, contactor 259a, wire 223a, cam switch 227a,

' wires 239a and wire 2550 to opening relay coil 219a and directional valve opening solenoid 96a, thereby maintaining both of these elements energized after the remote control relay 1650 is opened. Simultaneously, closure of opening relay contactor 269a, permits current to flow from lead 143, through wires 267, contactor 269a and wires 277 to velocity control valve relay coil 279, which whereby closes its armature 283, causing current to flow from the power source through

wires

143 and 267 to shut-off valve solenoid 89 with return through terminal 235, wire 237 and common negative wire 141, thereby opening shut-off valve 88 to permit pressurized hydraulic fluid to flow at low velocity through the restricted orifice 86 of valve 90 and conduit 92 into directional valve 93a, and thence through hose 9711 into hydraulic motor 25a, which it moves toward open position at low speed, opening switch 270 at the same speed.

Upon closure of opening relay contactor 269a by opening relay coil 219a when it was energized as described above, time delay relay 293 is also energized to open'its armature 299 (FIG. 10A) after a predetermined period, e.g. 15 seconds, and thereby break the circuit if due to some malfunction the circuit has not already been broken by cam switch 227a.

Normally when air break switch 70 reaches its full open position, cam 231a permits switch 227a to open, breaking the circuit from the power source to directional valve open solenoid 96a, and thereby closing directional valve 93a. This also breaks the circuit through wire 255a to opening relay coil 21911, which opens its armature contactors 259a and 269a, thereby breaking the circuit through shut-off valve relay coil 279, the armature 285 of which thereupon opens the circuit through

wires

267 and 287 to deenergize solenoid 89 and thereby shut off the flow of fluid through hydraulic conduit 92 and at the same time close the circuit through interlock switch 339 (if provided) toremote control relays 1650, b and 165c to enable them again to energize the command circuits as may be desired.

If it is desired to operate the switches locally, the operator depresses button of push and hold switch 155 to break the circuit through remote

control circuit contacts

153 and 157, and to connect

local control contacts

169 and 171, and then moves the selected local control switch a, 185b or 185a to the desired open or close position. For example, to close switch 7a, with button 175 of switch 155 held down, the operator manually throws switch 1850 to close contact 197a. Current then flows from power lead 143, through wire 145, pressure switch contact 105]. (if hydraulic pressureis within the prescribed range), interlock switch 339 (if provided) contactor 179, wire 181, manual switch 185a, contactor 197a,

wires

209a and 225a, closed cam switch 229a (closed when air break switch 7a is open), and wires 2411a to directional valve closing solenoid 98a via wire 246a, and to closing relay coil 221a via wire 257a. When thisoccurs, solenoid 98a moves directional valve slider 101a to connect conduit 92 with hose 99a leading to the closing side of motor 25a, and closing relay 221a closes its

armatures

261a and 271a.

The closure of armature 261a completes the holding circuit from wire 263 to directional valve closing solenoid 98a, and the closure of armature 271a energizes velocity control relay coil 279 to close its armature 283 and switch 339 (if provided). Closure of the former energizes valve solenoid 89 to open shut-off valve 88 permitting fluid to flow slowly through the restricted orifree 86 of valve 91), through conduit 92, directional valve 93a and hose 97a into the closing side of hydraulic operator 25a, thereby slowly moving air break switch 7a toward the closed position.

When switch 7a is approximately half way toward closed position, cam 391a closes switch 3030, to cause current to flow through wire 305a and 3119 to velocity control relay coil 311, which closes its armature 313, thereby causing current to flow from power lead 143, through wires 315 and 319 to velocity control valve solenoid 91.'The latter when energized fully opens velocity control valve 99, to permit fluid to flow at full speed through conduit 92, directional valve 93a and hose 97a, into hydraulic motor 25a, causing the latter to 7 complete closure of switch 7a at high speed, thereby minimizing arcing. Upon completion of the closing movement, cam 233a opens its switch 229a to break the circuits through directional valve solenoid 98a, thereby permitting directional valve 93a to close, and through close relay coil 221a, causing its

armatures

261a and 271a to open. The latter deenergizes flow control valve relay coil 279, whose armature 285 deenergizes flow control solenoid 99, permitting flow control valve 83 to close. At the same time, velocity control valve relay coil 311 is correspondingly deenergized, acting through its armature 313 to deenergize velocity control solenoid 91 and permit valve 90 to return to its normal restricted orifice position.

Attention is directed to the fact that because of the action of shut-off relay coil 279, all the local and remote command circuits are deenergized by its interlock armature 339 whenever any of the circuits is executing a command, so that only one command can be executed at a time. Also, the command to open or to close 1 cannot be executed unless the respective air break switch is closed or open respectively at the time the command is given, because of the operation of

cam valve switches

227a and 229a, 2271: and 229b, and

zontally to complete the desired opening or closing movement of the air break switch. If it is desired, upon completion of the movement, to lock the switch in this position, the handle can be swung vertically downwardly, and padlocked in the selected position.

For manual hydraulic operation of the air break switches, handle 47a, 49a will bepadlocked in the upright position with tooth 59a fitting into aligned

slots

55a and 57a.

The detailsof the apparatus disclosed herein may be modified substantially without departing from the spirit of the invention and the exclusiveuse of any modifications as come within the scope of the appended claims is contemplated.-

We claim:

1. Power apparatus for opening and closing an electric disconnect switch comprising a reversible fluid motor, means for mechanically connecting said fluid motor to the disconnect switch, a source of fluid pressure, normally closed fluid conduit means connecting said source of fluid pressure and said fluid motor and including electrically actuated means for opening said conduit means and for reversing the direction of said fluid motor, an electric power source, a pair of parallel selectively energizable electric control circuits for selectively energizing said electrically actuated means and thereby operating the disconnect switch in a desired direction to open or closed position, and means for preventing initial energization of either of said electrical control circuits during opening or closing move ments of the disconnect switch so that, once initiated, such movements of the disconnect switch will be completed to the fully-open or fully-closed positions without interruption.

2. Power apparatus according to claim 1 wherein said pressure source includes an electric motor and said conduit means includes a pressure-responsive electric switch electrically connected to said motor to start said motor when fluid pressure drops below a predetermined value and to stop said motor when pressure exceeds a higher predetermined value. I

3. Power apparatus according to claim 2 wherein a pressure accumulator is connected to said conduit means whereby to provide stored pressure in the event said electric motor becomes inoperable.

4. Power apparatus according to claim 1 in which said fluid motor has an output shaft, there being switch operating shaft means connected to the disconnect switch, means selectively releasably coupling said fluid motor output shaft and said shaft means, and an operating handle secured to said shaft means for rotation therewith.

5. Power apparatus according to claim 4 wherein said operating handle is swingable between an upright coupling position generally parallel with said shaft means, to a radial uncoupled position for manual operation, to a depending uncoupled position.

6. Power apparatus according to claim 4 wherein said coupling means includes a sleeve fixedly secured to said-operating shaft means and rotatably receiving said fluid motor shaft, said sleeve and said motor shaft having radially alignable apertures, said handle having a projection insertible into said apertures when both are aligned and said handle is in the upright position, for holding said motor shaft and said shaft means coupled to each other in rotation transmitting relation.

7. Power apparatus according to claim 6 wherein said motor shaft is axially slidable relative to said sleeve whereby to accommodate thermal contraction and expansion of said shaft means without affecting said motor.

8. Power apparatus according to claim 7 wherein said motor shaft aperture is longer axially of said shaft than the width of said handle projection whereby to accommodate axial sliding of said sleeve with respect to said motor shaft when said handle projection is inserted in said apertures.

9. Power apparatus according to claim 6 including means for locking said operating handle in the upright coupling position whereby to render said shaft rotatable only by said fluid motor and in the depending uncoupling position whereby to prevent any rotation of said shaft.

10. Power apparatus according to claim 1 wherein said means for opening said conduit means comprises an electrically actuated shut-off valve and said preventing means comprises a relay having a coil energizable upon energization of either of said control circuits and an armature normally connecting said control circuits with said electric power source, said armature being actuable when said relay coil is energized to disconnect said control circuits from said power source and connect said shut-off valve with said power source.

11. Power apparatus according to claim 1 wherein said preventing means comprises a fluid pressureresponsive switch controlling the supply of current from said power source to said control circuits, said switch being closed only when fluid pressure is above a predeterminedminimum value.

12. Power apparatus according to claim 2 wherein said preventing means comprises a set of contacts on said pressure-responsive switch, said set of contacts controlling the supply of current from said power source to said control circuits, said contacts being closed only when pressure is above a predetermined minimum value.

13. Power apparatus according to claim 1 wherein said fluid conduit means includes a fluid velocity control valve with a normally restricted orifice enlargeable responsive to partial movement of the disconnect switch toward closed position.

14. Power apparatus according to claim 1 wherein said fluid conduit means includes a normally restricted variable orifice and said electric control circuits include means for enlarging said orifice during the latter portion of the closing cycle of the disconnect switch and thereby accelerating movement of the disconnect switch to closed position.

15. Power apparatus according to claim 14 wherein said enlarging means is energized responsive directly to move-ment of said disconnect switch through a predetermined portion of its closing cycle.

16. Power apparatus according to claim 1 wherein said means for reversing the direction of said fluid motor comprises a directional valve in said fluid conduit means, there being switch means for selectively connecting either of said control circuits momentarily to said power source, one of said control circuits including electrical means for operating said directional valve in the opening direction and the other of said control circuits including electrical means for operating said directional valve in the closing direction, and means for maintaining the respective circuit energized after said switch means opens and until completion of the disconnect switch movement in the desired direction. i

17. Power apparatus according to claim 16 wherein said maintaining means in each said control circuit comprises a relay having its coil in said circuit and a normally open armature, a connection between said power source and said circuit including said normally open armature of said relay whereby when said circuit is initially energized by said switch means, said armature closes to complete said second connection to said power source.

18. Power apparatus according to claim 17 wherein each said control circuit includes breaking means responsive to completion of the disconnect switch movement caused by said circuit.

19. Power apparatus according to claim 18 wherein said fluid motor has an output shaft and said breaking means comprises switches operable by the movement of said fluid motor output shaft, the output shaft operable switch in the opening circuit being closed while the disconnect switch is open and open while the disconnect switch is closed, and the output shaft in the closing circuit being open while the disconnect switch is closed and closed while the disconnect switch is open whereby to prevent admission of fluid to either side of said fluid motor when the disconnect switch movement in the respective direction has been completed.

20. Power apparatus according to claim 18 in which said means for opening said fluid conduit means comprises a shut-off valve therein, there being electrical means responsive to energization of both said opening and closing control circuits for opening and closing said fluid shut-off valve.

21. Power apparatus according to claim 20 wherein said last named electrical means comprises a shut-off relay coil, means connecting said power source to said coil and including in parallel normally open additional armatures on the directional control circuit relays, whereby during energization of any of the directional control circuit relay coils the corresponding additional armature is closed to energize said shut-off relay coil.

22. Power apparatus according to claim 20 including a normally closed time delay switch in said second connection between said power'source and said control circuit operable responsive to energization of said control circuit a predetermined period after either of said control circuits is initially energized.

' 23. Power apparatus according to claim 20 wherein said fluid conduit means includes a normally restricted orifice, and said closing control circuits include electrical means for enlarging said orifice, said electrical means including a normally open switch connected to the respective control circuit and closable responsive to partial movement of the disconnect switch toward closed position.

24. Power apparatus according to claim 23 wherein said electrical orifice enlarging means includes a relay having its coil connected to said last-named normally open switch.

25. Power apparatus according to claim 24 wherein said orifice enlarging means comprises a solenoid operated valve containing said orifice, a connection between said power source and the solenoid, said enlarging means relay having. a normally open armature in said last-named connection.

26. Power apparatus according to claim 25 including electrical circuit means containing indicator lights of different colors to denote the open and closed condition of the disconnect switch, and normally open switches in said electrical circuit means closable responsive to movements of the disconnect switch to open or closed position for energizing the respective indicator lights.

27. Power apparatus according to claim 26 wherein a cabinet encloses said control circuits, said cabinet having a door, there being an additional normally open switch in said circuit means closable-responsive to opening of said door to keep said electrical circuit means containing said indicator lights broken when said door is closed.

'28. Power apparatus for opening and closing a plurality of electric disconnect switches, comprising for each disconnect switch a reversible fluid motor, means for mechanically connecting said fluid motor to the disconnect switch, a source of fluid pressure, nonnally closed fluid conduit means connecting said source of fluid pressure and said fluid motor and including electrically actuated means for opening said conduit means and for reversing the direction of said fluid motor, an electric power source, a pair of parallel selectively energizable electric control circuits for selectively energizing said electrically actuated means and thereby operating the associated disconnect switch in a desired direction to open or closed position, and means for preventing initial energization of any of said electrical control circuits during opening or closing movements of any of thedisconnect switches so that, once initiated, such movements of any of the disconnect switches will be completed to the fully-open or fully-closed positions without interruption.

29. Power apparatus for operating an electric disconnect switch comprising a motor having an output shaft, switch operating shaft means operably connected to the switch, said output shaft and operating shaft means having adjacent portions in axial alignment with each other, a releasable coupling connecting said output shaft and said switch operating shaft means, said coupling including a sleeve rigidly connected to said operating shaft means and rotatably surrounding said output shaft, said sleeve and said output shaft having radially alignable apertures, a handle pivotally mounted on said sleeve for movement between positions parallel with said aligned portions of said output shaft and said operating shaft means, said handle having a projection insertible in said radially alignable apertures when said apertures are aligned and said handle is generally parallel to said aligned portions of said output shaft and said operating shaft means for holding said output shaft and said shaft means in rotation transmitting relation with each other.

30. Power apparatus according to claim 21 wherein said motor shaft is axially slidable in said sleeve whereby to accommodate thermal contraction and expansion of said shaft means without affecting said mo- 31. Power apparatus according to claim 30 wherein said motor shaft aperture is longer axially of said shaft than the width of said handle projection whereby to accommodate axial sliding of said sleeve with respect to said motor shaft when said handle projection is inserted in said apertures.

32. Power apparatus according to claim 29 wherein said aligned apertures are above the pivotal-mounting of said handle to said sleeve and said handle projection is on top of said handle when said handle is radially extended.

33. Power apparatus according to claim 32 including a pair or arcuately spaced radially slotted members fixedly positioned with respect to said motor below said handle and defining the limits of arcuate movement of wardly extending position generally parallel with said aligned portions of said shaft and shaft means with said handle top projection in said aligned apertures in said sleeve and shaft, and in a downwardly extending position.

35. Power apparatus according to claim 33 wherein said operating shaft means includes a universal joint.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 a 761 r 735 Dated September 25, 1.973

Invent0r(s) John L. Turner; Fred L. Diener It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 13, lines 26 and 59, delete "second";

Column 15, line 3, "Power apparatus according to claim 21" should read: "Power apparatus according to claim 29".

Signed and Scaled this eighteenth D ay 0; No vember 1 9 75 [SEAL] A ttesr:

RUTH C. MASON UNITED STATES PATENT OFFICE CERTIFICATE 0E CORRECTION Patent No. 3,761,735 Dated September 25, 1973 Inventor(s) John L. Turneg; Fred L. Diener It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 13, lines 26 and 59, delete "second";

Signed and Scaled this A nest:

RUTH C. MASON .-l!!v.s'!mg Officer C. MARSHALL DANN ('mnmim'mu'r of Parents and Trudemurkx

Claims

1. Power apparatus for opening and closing an electric disconnect switch comprising a reversible fluid motor, means for mechaniCally connecting said fluid motor to the disconnect switch, a source of fluid pressure, normally closed fluid conduit means connecting said source of fluid pressure and said fluid motor and including electrically actuated means for opening said conduit means and for reversing the direction of said fluid motor, an electric power source, a pair of parallel selectively energizable electric control circuits for selectively energizing said electrically actuated means and thereby operating the disconnect switch in a desired direction to open or closed position, and means for preventing initial energization of either of said electrical control circuits during opening or closing movements of the disconnect switch so that, once initiated, such movements of the disconnect switch will be completed to the fully-open or fully-closed positions without interruption.

2. Power apparatus according to claim 1 wherein said pressure source includes an electric motor and said conduit means includes a pressure-responsive electric switch electrically connected to said motor to start said motor when fluid pressure drops below a predetermined value and to stop said motor when pressure exceeds a higher predetermined value.

6. Power apparatus according to claim 4 wherein said coupling means includes a sleeve fixedly secured to said operating shaft means and rotatably receiving said fluid motor shaft, said sleeve and said motor shaft having radially alignable apertures, said handle having a projection insertible into said apertures when both are aligned and said handle is in the upright position, for holding said motor shaft and said shaft means coupled to each other in rotation transmitting relation.

11. Power apparatus according to claim 1 wherein said preventing means comprises a fluid pressure-responsive switch controlling the supply of current from said power source to said control circuits, said switch being closed only when Fluid pressure is above a predetermined minimum value.

16. Power apparatus according to claim 1 wherein said means for reversing the direction of said fluid motor comprises a directional valve in said fluid conduit means, there being switch means for selectively connecting either of said control circuits momentarily to said power source, one of said control circuits including electrical means for operating said directional valve in the opening direction and the other of said control circuits including electrical means for operating said directional valve in the closing direction, and means for maintaining the respective circuit energized after said switch means opens and until completion of the disconnect switch movement in the desired direction.

22. Power apparatus according to claim 20 including a normally closed time delay switch in said second connection between said power source and said control circuit Operable responsive to energization of said control circuit a predetermined period after either of said control circuits is initially energized.

23. Power apparatus according to claim 20 wherein said fluid conduit means includes a normally restricted orifice, and said closing control circuits include electrical means for enlarging said orifice, said electrical means including a normally open switch connected to the respective control circuit and closable responsive to partial movement of the disconnect switch toward closed position.

25. Power apparatus according to claim 24 wherein said orifice enlarging means comprises a solenoid operated valve containing said orifice, a connection between said power source and the solenoid, said enlarging means relay having a normally open armature in said last-named connection.

28. Power apparatus for opening and closing a plurality of electric disconnect switches, comprising for each disconnect switch a reversible fluid motor, means for mechanically connecting said fluid motor to the disconnect switch, a source of fluid pressure, normally closed fluid conduit means connecting said source of fluid pressure and said fluid motor and including electrically actuated means for opening said conduit means and for reversing the direction of said fluid motor, an electric power source, a pair of parallel selectively energizable electric control circuits for selectively energizing said electrically actuated means and thereby operating the associated disconnect switch in a desired direction to open or closed position, and means for preventing initial energization of any of said electrical control circuits during opening or closing movements of any of the disconnect switches so that, once initiated, such movements of any of the disconnect switches will be completed to the fully-open or fully-closed positions without interruption.

30. Power apparatus according to claim 21 wherein said motor shaft is axially slidable in said sleeve whereby to accommodate thermal contraction and expansion of said shaft means without affecting sAid motor.

31. Power apparatus according to claim 30 wherein said motor shaft aperture is longer axially of said shaft than the width of said handle projection whereby to accommodate axial sliding of said sleeve with respect to said motor shaft when said handle projection is inserted in said apertures.

32. Power apparatus according to claim 29 wherein said aligned apertures are above the pivotal mounting of said handle to said sleeve and said handle projection is on top of said handle when said handle is radially extended.

33. Power apparatus according to claim 32 including a pair or arcuately spaced radially slotted members fixedly positioned with respect to said motor below said handle and defining the limits of arcuate movement of said output shaft, said handle being formed with a second projection on the bottom of said handle alternately receivable in said slotted members when said handle is in the downwardly extending generally parallel position.

34. Power apparatus according to claim 33 including means for selectively locking said handle in an upwardly extending position generally parallel with said aligned portions of said shaft and shaft means with said handle top projection in said aligned apertures in said sleeve and shaft, and in a downwardly extending position.