US1481884A - Circuit-interrupter interlock - Google Patents

Circuit-interrupter interlock Download PDF

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US1481884A
US1481884A US468556A US46855621A US1481884A US 1481884 A US1481884 A US 1481884A US 468556 A US468556 A US 468556A US 46855621 A US46855621 A US 46855621A US 1481884 A US1481884 A US 1481884A
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lever
switch
starting
running
pin
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US468556A
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Andrew H Bakken
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H9/00Details of switching devices, not covered by groups H01H1/00 - H01H7/00
    • H01H9/20Interlocking, locking, or latching mechanisms
    • H01H9/26Interlocking, locking, or latching mechanisms for interlocking two or more switches
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/20Control lever and linkage systems
    • Y10T74/20207Multiple controlling elements for single controlled element
    • Y10T74/20238Interlocked

Definitions

  • My invention relates to mechanical interlocking devices that are adapted to insure the proper relative movements of a plurality ot levers, such as are employed in connection with the operation o electric switches.
  • My invention is designed especially for use in connection with electric motors that require a relatively low voltage when being started to bring them up to, and a higher voltage to maintain them at, their normal running speeds.
  • One object ot my invent-ion is,V to provide a construction wherein the switch that con trols the low-voltage circuit must be moved to closed position and then completely opened beiore the switch that controls the high-voltage circuit can be closed and wherein each switch is held against closing movement while the other switch is in closed po sition.
  • Another object is to provide means whereby the switch that controls the high-voltage circuit cannot be moved to closed position except within a limited time after the lowroltage circuithas been opened.
  • Figure 1 is a view, inside elevation, of a 1921. Serial No. 468,556.
  • circuit breaker having a device embodying my invention applied thereto;
  • Fig. 2 is a side elevation,partially in section
  • Fig 3 is an elevational view, looking from the lright of Figs. 1 and 2;
  • Fig. il is a plan view of the supporting bracket which forms part of my device.: 1. 1 i l* ig. 5 shows side and front elevational views of a portion of my device;
  • Fig. 6 comprises views, in side ⁇ and in Y front elevation, ot another portion of my device, and o Figs. 7 and 8 are views showing the positions occupied by certain of the apparatus at one stage oitv operation.
  • The' invention is shown -as applied to oill circuit breaker 9 of an ordinary type that is provided with a supportingV frame 10 and a tank 11.
  • the operating lever 12 is pivoted to the trame 10 and is connected-to a cross-bar lever ⁇ 13, through a toggle link 14.
  • the crossbar lever 13 carries a cross-bar 15 lwhich has operating rods 15a that aie arranged to operate the circuit-closing contact members of alow-voltage switch, in the usual manner, to close a low-voltage circuit through a motor (not shown).
  • an operating lever 16 is provided for controlling, through a toggle link 17, a cross-bar lever 1S, a crossbar 19 and operating rods "19a, a high volt- K age circuit through they motor.
  • the toggle link 14 is connected to the lever 13 by a pin 2() the ends'of which-are extendedin the vmanner shown more clearly in Fig. 3, and the toggle lever 17 is connected to the lever 18 by apin 21 that also has its ends extended as shown inFig. 3.
  • fi bracket '24 which is securedV to the Y 'frameworkl by means of a bolt 25, is provided with a pair of projections 26 and 27 through which a. pin 28 extends, and is also provided w-itlia pair of ears 29 through which a pin 30 extends. 1 f
  • a latch member 31 is plivotally supported on the pin 30, while a locking. lever 32 is pivotally supported bythe pin 28.
  • the pin 28 serves also as a pivot for an idler lever 33.
  • rilhelocking lever 32 is provided with Vsov four depending arms 35, 36, 37 and 38 that are adapted to cooperate with the pins 20 and 2l, while the idler lever 33 is provided with a depending arm 39 that is adapted to cooperatewvi'th ⁇ the pin 21.; andan armdO whiclrserves merely to increase the weight of the idler lever.
  • the locking lever 32 is returned to'locked ⁇ engagement with the latch 31 and the idler lever 33again bars the pin 21 against movement to closed'positiom while'the pin 20ct the starting-switch lever has an unobstructedl path for movement to its closed position.
  • the operating lever 12 is movedfto its Htheleg 39 of such lever out of closed position, as illustrated in Figs. 1, 2 and 3, thus bringing the pin 20 into engagement with the latch 31 to trip the same and permitting the locking lever 32 to swing downwardly about the pivot 28.?
  • the projection 35 of the locking lever 32 is advancement of the sition, whether the lever 32 occupies the position of Fig. 1, or whether it is in latched engagement with the member 31, but the projection 39 of the idler lever 33 extends made wide enough at its lower end to bar pin 21 to advanced poi slightly farther than does the projection* 35.
  • the idler lever 33 may be dispensed with, in which case the pin 21 would be normally barred against advancement directly by the projection 35, but. the idler lever 33 Serves the additional function of sopositioning the pin 21 that it may; be readily snapped' into position when brought downwardly to release thegpin 21. Vith the'leve'r '33 removed and the-'pin 21 projection' 35, the lever-'32 wouldnot-swing as readilyto the position of Figs. 20 is swung downwardly.
  • sequence interlockv comprising a lever pivoted eccentrically of its center of gravity and normallyrestrained Jfrom movementvto its lovvermost position, a projection on the pivoted lever adapted tov bar movement of the running-switch lever to closed position when .the said pivoted lever occupies its normal position, a second projection adapted to bar movement of the starting-switch lever When the iirst-named projection has freed the running-switch lever, and means operated by tlie starting-switch lever durling its movement to open position for movy ing ⁇ the iirst projection out of the path of ,the running-switch lever.
  • ystartingy a pivoted lever normally positioned so that gravity lies in a substantially its center of horizontal Vdirection to its point of pivotal support, means fory releasably holding the pivoted lever in its normal position, a projection on the pivoted lever adapted, when in normal position, to bar advancement of the running-switch lever to closed position, a second projection on the-said pivoted lever adapted to bar advancement of the startingswitch lever to closed position when the pivoted lever is in released position with respect to the running-switch lever, means actuated by the starting-switch lever, during its closing movement, for releasingthe pivoted lever, a ⁇ cam member carried by the pivoted lever in position to swing under the starting-switch lever when such lever is being moved to its closed position, means lactuated by the starting-switch lever durtor releasably lioldf lever: and a running-switch lever, .ofrapivoted member adapted, when in.4 normal position, to bar advance-ment

Description

Jan; 29, 1924.
1,481,884 v A. H. BAKKEN CIRCUIT INTERRUPTER INTELoc'K Filed may 11, 1921 2 Sheets-:Shreetl O wnNEssEs: v xNvENToR 117091911015?czkf'verl,
. l; ATTRNEY Patented Jan., 29, 1924.
is arts ANDREW' II. BAKKEN, OF EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC @c MANUFACTURING VANIA.
COMPNY, A CORPORATION 0F PENNSYL- CIRCUIT-INTERR-UPTER INTERLDCK.
Application filed May 11,
[o @ZZ whom t may concern.
Be it known that I, ANDREW H. BAKKEN, a citizen of the United States, and a resident ot' Edgewood Park, in the county of Allegheny and State of Pennsylvania, have invented a new and useful. Improvement in Circuitflnterrupter Interlocks, of which the following is a specification.
My invention relates to mechanical interlocking devices that are adapted to insure the proper relative movements of a plurality ot levers, such as are employed in connection with the operation o electric switches.
My invention is designed especially for use in connection with electric motors that require a relatively low voltage when being started to bring them up to, and a higher voltage to maintain them at, their normal running speeds.
One object ot my invent-ion is,V to provide a construction wherein the switch that con trols the low-voltage circuit must be moved to closed position and then completely opened beiore the switch that controls the high-voltage circuit can be closed and wherein each switch is held against closing movement while the other switch is in closed po sition. Y
Another object is to provide means whereby the switch that controls the high-voltage circuit cannot be moved to closed position except within a limited time after the lowroltage circuithas been opened.
Various types ot apparatus have been designed to automatically provide for the proper sequence of operation, as between Va starting switch and a running, or high-voltage, switch, but diiiiculty has been experienced in designing a structure wherein provision is madeY to insure the closing of the running switch before the motor has lost the momentum set up therein through the operation of the starting switch.
l provide a construction wherein the iunning switch must be closed, if at all7 at substantially the instant that the starting switch lever reaches'its Vopen position, and one wherein the use of springs, with the difficulties incident thereto, are avoided.
In the accompanying drawings:
Figure 1 is a view, inside elevation, of a 1921. Serial No. 468,556.
circuit breaker having a device embodying my invention applied thereto;
Fig. 2 is a side elevation,partially in section; y
Fig 3 is an elevational view, looking from the lright of Figs. 1 and 2;
Fig. il is a plan view of the supporting bracket which forms part of my device.: 1. 1 i l* ig. 5 shows side and front elevational views of a portion of my device;
Fig. 6 comprises views, in side `and in Y front elevation, ot another portion of my device, and o Figs. 7 and 8 are views showing the positions occupied by certain of the apparatus at one stage oitv operation.
The' invention is shown -as applied to oill circuit breaker 9 of an ordinary type that is provided with a supportingV frame 10 and a tank 11.
The operating lever 12 is pivoted to the trame 10 and is connected-to a cross-bar lever` 13, through a toggle link 14. The crossbar lever 13 carries a cross-bar 15 lwhich has operating rods 15a that aie arranged to operate the circuit-closing contact members of alow-voltage switch, in the usual manner, to close a low-voltage circuit through a motor (not shown). Y
vIn a similar manner, an operating lever 16 is provided for controlling, through a toggle link 17, a cross-bar lever 1S, a crossbar 19 and operating rods "19a, a high volt- K age circuit through they motor.
The toggle link 14 is connected to the lever 13 by a pin 2() the ends'of which-are extendedin the vmanner shown more clearly in Fig. 3, and the toggle lever 17 is connected to the lever 18 by apin 21 that also has its ends extended as shown inFig. 3.
fi bracket '24 which is securedV to the Y 'frameworkl by means of a bolt 25, is provided with a pair of projections 26 and 27 through which a. pin 28 extends, and is also provided w-itlia pair of ears 29 through which a pin 30 extends. 1 f
A latch member 31 is plivotally supported on the pin 30, while a locking. lever 32 is pivotally supported bythe pin 28. The pin 28 serves also as a pivot for an idler lever 33.
rilhelocking lever 32 is provided with Vsov four depending arms 35, 36, 37 and 38 that are adapted to cooperate with the pins 20 and 2l, while the idler lever 33 is provided with a depending arm 39 that is adapted to cooperatewvi'th `the pin 21.; andan armdO whiclrserves merely to increase the weight of the idler lever.
Vhen-v the switch-operatingy levers=f12 Iand 16,1 arerin neutral-position, the pins 20 and 21 are both in the horizontal plane occupied by the pin 21 in Fig. 1, andithe locking lever 32 is engaged by the latch 31. This engagement occurs when the locking lever 32occupies a position intermediate those of Figs. 1 andA 7.
When the locking lever 32 is in latched position, the movement of the pin 21 is unobstructed by the arm 36, and the pin 20 is free to be moved upwardly between the arms 37 and 38. However, the depending arm' 39 of the idlerlever 33 normally blocks the passage4 of the pin 21 to its upper or closed position.
If now the' operating lever 12 be moved 'to its closed position, as illust-rated in Figs. 1 and 3, the pin`20 will trip the latch 31 and permit the .locking ,lever 32 to swing to the position illustrated in Figs. 1 and 2, under the acti-on of gravity., This movement of the locking lever 32"`causes the arm 37 to swing into position under the pin 20 F ig.y v2) If the starting-switch lever 12 be then raised quickly, the pin 2O will descendrapidly to its loweror open position, imparting a cam action to the arm 37 and causing thel locking` lever 32 to swing tothe position illustrated Vin` Figs. 7 and 8. While the locking lever is moving to this position, the pin'21 of the running-switch lever 16 is unn `covered by the arm 35. and the pin 21 may be moved to closed position, provided it has. in the meantime, been unlocked from its engagement with thearm 39 ofthe lever 33. When the pin 21 has reached its closed position, as indicated in Figs. 7 and 8, the arm-38 of the lever 32will lie in the path of the pin 20 o f the startingfswiteh lever 12 to prevent movement thereof to closed posi- V tion and, so long as the running-switch lever remains closed, the starting-switch lever cannot be closed. When the running-switch lever 16 is returned to open position ,(Fig. 1), the locking lever 32 is returned to'locked `engagement with the latch 31 and the idler lever 33again bars the pin 21 against movement to closed'positiom while'the pin 20ct the starting-switch lever has an unobstructedl path for movement to its closed position.
Starting with the operating levers 12' and 16 int-heir uppermost or open positions and thepins 2O `andA 21, consequently, in their lowermost positions, the operation of the device is as follows:
The operating lever 12 is movedfto its Htheleg 39 of such lever out of closed position, as illustrated in Figs. 1, 2 and 3, thus bringing the pin 20 into engagement with the latch 31 to trip the same and permitting the locking lever 32 to swing downwardly about the pivot 28.?
Meantime, the lever l'has been depressed to bring the pin 21 into engagement with the arm 39 of the lidler lever 33 and pressure is maintained on the lever 16, so that, when the arm 39 shall have been tripped out of engagement-with the pin 21. the pin 21 will advance upwardly with a snap movement, If now the lever 12 be raised quickly. the cam action imparted by the pin 21 to the arm 37 will cause the locking lever 32 to swing slightly past the position shown in F ilgs. 7 and 8 and, during suclrswinging movement, the' lever 32 will abut against a projection 40 on the idler lever 33 and trip y engagement with the pin 21 and asv the leg 35 of the lockingl lever 32 swings clear of the path of the pin A21, the pin 21, being under stress, will snap up into its closed position, as shown in 1g. Because of the fact that, when in this position, the pm 21 maintains the locking lever 32 in such relation tothe pin 20 that the pin is heldagainst upward movement, the starting-switch lever cannot be advanced until the running-switch lever and the pin 21 carried'thereby have been returned to neutral position, and it is equally apparentthat the.
running-switch closed position until the starting switch lever has completed a cycle of movement and that, even under that condition, the runlever cannot be moved to ning-switch lever must be advanced, if at.. all, before the locking member 32 returned to its normal or locked position, under the action of gravity.
The projection 35 of the locking lever 32 is advancement of the sition, whether the lever 32 occupies the position of Fig. 1, or whether it is in latched engagement with the member 31, but the projection 39 of the idler lever 33 extends made wide enough at its lower end to bar pin 21 to advanced poi slightly farther than does the projection* 35.
as shown in Fig. 3, and the pin-31 nornialy cgi-operates with the projection 33, if desired, the idler lever 33 may be dispensed with, in which case the pin 21 would be normally barred against advancement directly by the projection 35, but. the idler lever 33 Serves the additional function of sopositioning the pin 21 that it may; be readily snapped' into position when brought downwardly to release thegpin 21. Vith the'leve'r '33 removed and the-'pin 21 projection' 35, the lever-'32 wouldnot-swing as readilyto the position of Figs. 20 is swung downwardly.
Various other changes in the details of the pin-21l is i svvitch lever and construction might be made without avoiding the spirit of the invention, as defined in the accompanying` claims.
I claim as my invention:
l. The vcombination With a startingsvvitch'lever and a running-switch lever, of a sequence interlock comprising a lever pivoted eccentrically of its center of gravity and normally restrained from movement to its lovvermost` position, a projection on the pivoted lever adapted to bar movement of the running-switch lever to closed position when the said pivoted lever occupies its normal position, a second projection adapted to bar movement of the starting-switch lever` When the first-named projection has freed the running-switch lever, and means Vvoperated by the starting-switch lever during its cycle of movement for moving fthe first projection out of the path of the runningfor moving the second projection into the path of movement of the starting-switch lever.
i 2. The combination vvitli.` a starting- Yswitch lever and-a running-switch lever, of
a. sequence interlockv comprising a lever pivoted eccentrically of its center of gravity and normallyrestrained Jfrom movementvto its lovvermost position, a projection on the pivoted lever adapted tov bar movement of the running-switch lever to closed position when .the said pivoted lever occupies its normal position, a second projection adapted to bar movement of the starting-switch lever When the iirst-named projection has freed the running-switch lever, and means operated by tlie starting-switch lever durling its movement to open position for movy ing` the iirst projection out of the path of ,the running-switch lever.
3. The combination with a lstartingsvvitch lever and a running-switch lever', of apivoted lever normally positioned so that its center' of gravity lies in a substantially horizontal directionv from its point ot pivotal support, means for releasably holding the pivoted lever in its normal position,
a projectionon the pivoted lever adapted, ivlien in normal position,.to -bar advancement of the Vrunning-,switch lever to closed position, av second projection on the said pivoted lever adapted to bar advancement ofthe kstarting-switchl lever to closed position When the pivoted lever is in released position With respect to the running-switch lever, means actuated by the starting-switch lever during its closing` movement for releasing the pivoted lever, and means actuated by the starting lever during its opening movement for moving the pivoted lever to released position and in locked position with respect to the starting-switch lever.
et. The combination With a startingsvvitch lever and a running-switch lever, of a pivoted lever normally positioned so'that its center of. gravity lies in a substantially horizontal direction from its point ot pivotal support, means ing the pivotal lever in its normal position, a projection on the pivoted lever adapted, When in normal position, to bar advancement ot the running-switch lever to closed position, Va second projection on the said pivoted lever adapted to bar advancement of the starting-switch lever to closed position when the pivoted lever is in released position with respect to the running-switch lever, means actuated by the starting-switch lever during its closing movement Jfor releasing tlie pivoted lever, a cam member carried by the pivoted lever in position to swing under the starting-switch lever when such lever is being moved to its closed position, means actuated by the starting-switch lever during its closing movement toreleasetlie pivoted lever, and a member carried by the starting-switch lever for engaging' said cam memberl to swing the pivoted lever to released position With respect to the running-switch lever and to locked position With respectto thestarting-svvitch lever during a rapid movement ot the starting-switch lever to open position.
5. The combination With a svvitchlever and a running-switch lever,
ystartingya pivoted lever normally positioned so that gravity lies in a substantially its center of horizontal Vdirection to its point of pivotal support, means fory releasably holding the pivoted lever in its normal position, a projection on the pivoted lever adapted, when in normal position, to bar advancement of the running-switch lever to closed position, a second projection on the-said pivoted lever adapted to bar advancement of the startingswitch lever to closed position when the pivoted lever is in released position with respect to the running-switch lever, means actuated by the starting-switch lever, during its closing movement, for releasingthe pivoted lever, a `cam member carried by the pivoted lever in position to swing under the starting-switch lever when such lever is being moved to its closed position, means lactuated by the starting-switch lever durtor releasably lioldf lever: and a running-switch lever, .ofrapivoted member adapted, when in.4 normal position, to bar advance-ment ofthe runningsvvitch lever to closed position and, wheniiii another' position, tol bar advancement: of the starting-switch lever to closed position, means for releasably maintaining thelrpivoted member in normal position, means actuated by the starting-switch lever for releasing the pivoted member, and other means actua-ted there-by for moving saidy p ivoted lever -to locked position with respect to the starting-switch lever.
7. The combination with ya starting-switch lever and a running-switch lever, or' a pivoted member adapted, when in normal position, to bar advancement of the. runningswiteh lever to closed position and, when in another position, bar advancementl of the starting-switch lever to closed position, means for releasably maintaining' the `pivoteolV member in normal position, means actuated by the starting-switch lever, during its movement to= closed position, for releasing the pivoted lever, and other means actuated thereby'` for moving said pivoted Vlever to locked position with respect to the' starting switch lever. i
8. The combination with a startingswitch lever and a running-switch lever, of a pivoted member adapted, when in'normal position, to bar advancement of the runningswitch level'l to closed position and, When in another position, to bar advancement of the `starting-switch lever to closed position, means for releasably maintaining the pivoted member in normal position, means actuated by the starting-switch lever, during its movementvto closed position, for releasing the pivoted lever, and other means actuated thereby, during its movement to open position, for moving said pivoted lever to locked position with respect to the starting-switch lever.
9. 'The combination With a startingswitch lever and a running-switch lever, of aneccentrically mounted, pivoted member (zo-operating With the running-switch lever, when the running-switch lever is in closed position, to bar movement of the starting-switch lever to closed positionfa positioning member normally in position to lbe engaged by the running-switch levery to bar Malisse advancementthereof to closed position,- a projection on the pivotedv memberl normally lying in the path offmovementaof:thefrunningswitch lever, au secondMpro-ject-ion provided Witlra cani surface adaptedsto, be'vengaged i leverxto permit. the advancement of said lever` to closed position.
10.1Tlie combination Withi twol reciprocably movable sWitchmemberm-O means-'for preventing the advancementorI one member exceptat substantially the instanty that the other member `has tion.
ll. The combination with a. startingswitch lever and a running-switch lever, of a pivoted member co-operating Withithe running-switeh lever is in closedpositionyto bar-movement of the starting-switch l lever `to closed lposition, a second pivoted member normally in position to bar advancement of the' runningswitch lever to closed position, `and means actuated by the starting-switch lever, during its movement -to open position, tomove-the second-named` pivoted member out of the pathv of movement of the yrunning-svvitch lever. f
12. The combination with startingsivitch lever and a running-switch leven-of a pivoteol member co-operatingWitlrithe running-switch lever, when the running-switch lever is in closedposition-,to bar movement of the starting-switch lever to a closed position, a secondf'pivoted member normally in position to bar advancement of the runningswitcli lever to closed position, and means actuated l by the starting-switch leverv atthe completion of a cycle of movement thereof tov move the second pivotedmember and permit advancement of 'the' running-switch lever toclosed position.
In testimony whereof, 'I 'have hereunto subscribed my name this 28th* day of April ANDREW 'H-. BAKKEN;
reached a retractinglposilever, vvhen thel running-switch
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2558070A (en) * 1946-05-07 1951-06-26 Westinghouse Electric Corp Circuit breaker

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2558070A (en) * 1946-05-07 1951-06-26 Westinghouse Electric Corp Circuit breaker

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