US2348021A - Electric switch - Google Patents

Electric switch Download PDF

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US2348021A
US2348021A US483978A US48397843A US2348021A US 2348021 A US2348021 A US 2348021A US 483978 A US483978 A US 483978A US 48397843 A US48397843 A US 48397843A US 2348021 A US2348021 A US 2348021A
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toggle
switch member
switch
coil
arm
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US483978A
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John A Oppel
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General Electric Co
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General Electric Co
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H50/00Details of electromagnetic relays
    • H01H50/16Magnetic circuit arrangements
    • H01H50/18Movable parts of magnetic circuits, e.g. armature
    • H01H50/30Mechanical arrangements for preventing or damping vibration or shock, e.g. by balancing of armature

Definitions

  • My Invention relates to switches, more particularly to electromagnetically operated switches, such as contactors, and has for its object a simple and reliable contactor which is automatically locked in both its open and closed circuit positions against operation by severe shocks.
  • I utilize two toggle mechanisms, one of which is closed when the switch is open thereby to lock the circuit breaker in its open circuit position, and the other of which is closed to lock the circuit breaker when in its closed circuit position.
  • I provide an operating electromagnet having a two-part plunger armature, together with two bell crank arms mounted on stationary central pivots and each having an end pivotally connected to an outerend of one of the plunger armatures, as described and claimed in a copending application, Serial No. 432,724, filed by John E. Lake on February 28, 1942, assigned to the same assignee as this application, and of which my invention is an improvement.
  • the aforementioned application issued as Patent No. 2,336,871 on December 14, 1943.
  • a pivotal connection is provided between the other ends of the bell cranks, which connection is connected through a link to an arm connected to operate the switch mechanism.
  • this link and one arm of one of the bell cranks forms a closed toggle locking the circuit breaker in its closed position
  • a second toggle is provided having one end connected to the circuit breaker operating arm and its other end connected to a stationary pivot.
  • FIG. 1 is an elevation view showing a circuit breaker embodying my invention in its open circuit position; while Fig. 2 is a view similar to Fig. 1 but showing the circuit breaker in its closed circuit position.
  • the circuit breaker or contactor in one Aform of my invention is operated by a magnet coil Il) having two plunger armatures II and I2 movable axially with respect to the coil toward and away from each other.
  • the outer ends of these plungers are connected by pivotal connections I3 and I 4 to the ends of bell crank arms I5 and I6 having stationary central pivots I'I and I8.
  • the other ends of the bell cranks are connected pivotally together by means of a pivot pin I9, the arm I6 having a slot for the pivot pin extending lengthwise of this arm of the bell crank and providing a loose connection betweenthe bell crank I6 and the pivot pin to provide for movement of the bell' open circuit position, as shown in Fig.
  • a toggle l5 21 is provided having its upper end connected by means of a pivot 28 to an extension 29 on the armr 24, This extension is on the side of the ,f shaft 25 opposite ,the pivot 23, At its lower end the toggle 21 is connected to a stationary pvot 30.
  • coiled around the movable pivot 32 of this toggle biases the toggle to its broken position, as shown in Fig. 2.
  • the two plungers II and I2 are drawn magnetically ⁇ toward each other into the interior oi the coil, the two ends of the plungers preferably engaging each Yother when the plungers are in their fully attracted positions, as shown in Fig. 2.
  • the bell cranks I5 and I6 are turned, respectively, in clockwise and counterclockwise directions about the stationary pivotsll and I8 to the positions shown in Fig. 2, and the toggle 21 is broken toward the left by the spring 3
  • the pivot I 9 moves toward the left hand. as seenin the drawing, and
  • the toggle formed by the link 22 and the upper arm of the bell crank I8 is in its closed or made position with the pivot pin It engaging the lower wall of the slot 20, whereby the arm 2
  • may be 'suitably secured to the shaft 25.n As shown, it is pivotally mounted in a U-shaped member 31 which, in turn, is secured by a. bracket 38 to the shaft. AA helical spring 39 is secured between the contact 2
  • the arrangement is such that the contact 2
  • the slot 40 provides for a small amount of movement of the pin I9 toward the left hand when the coil is energized whereby the member 33 is moved toward the left to provide for breaking of the toggle 21 by the spring 3l.
  • the pin I9 engages the upper wall of the slot 40 so that the link 22 forms with the upper arm of the bell crank I6 a solid toggle in its closed position.
  • the double plunger armature arrangement is in itself shockproof since the two plungers and I2 have equal masses and move in opposite directions.
  • the coil and magnet frame in the closed position with the inner ends of the two plungers in engagement with each other as shown in Fig. 2, and the outer heads of the plungers spaced from the coil and its magnet frame, the coil and magnet frame have considerable freedom of movement during a shock with respect to the plungers themselves and without transmitting this shock movement to the plungers.
  • a switch comprising a switch member movable between open and closed circuit positions, operating means for said switch member, a linkage operating connection including two bell cranks operatively connecting said 4operating means with said switch member whereby said switch member is moved between open and closed circuit lpositions by said operating means,l said linkage including a toggle having one end connected pivotally to be movable in accordance with the movements of said switch member and itsother end mounted on a stationary pivot, and y a second toggle having one end connectetLpivotally to said switch member for movement in accordance with the movements of said switch member and its other end mounted on a stationary pivot, said toggles being arranged to be moved between made and broken positions upon movement of said switch member between its open and closed circuit positions and one of said toggles being in its made position in each of said switch member positions thereby to secure said switch member in said position.
  • a switch comprising a switch member movable b tween open and closed circuit positions, coil, a pair of armatures movable usly by said coil, a linkage operating connection including two bell cranks operatively connecting said armatures with said switch member whereby said switch member is moved between open and closed circuit positions by said coil, said linkage including a toggle having one end vconnected pivotally to be movable in accordance with ⁇ the Vmovements of said switch member, and asecond toggle having one end connected pivotally to said switch member for movement in accordance withfthe movements oi' said switch member and its other end mounted on a stationary pivot, said toggles being arranged to be moved between made and broken positions upon movement of said switch member between its open and closed circuit positions and one of e said toggles being in its made position in each of said switch member positions thereby to secure said switch member in said positions.
  • 3,'An velectromagnetically operated switch comprising a movably mounted switch member, an operating coil, a pair of armatures for said coil, a pair oi' bell crankl arms mounted on stationary pivots, a pivotal connection between one end of each oi' said bell cranks and one of said armatures, va pivotal connection between the other endsof said bell cranks, means connectinga't ⁇ least one of said bell cranks with said switch member, a toggle having one end conne cted to said switch member and its other end connected to a'xed pivot, and means for holding ⁇ said toggle in its made position when said switch memberis in one position.
  • An elcctromagnetically operated switch comprising amovably mounted switch member, an operating coil, a pair of armatures for said coil extending into said coil and moving axially of said coil, a'pair of bell crank arms mounted on stationary pivots, a pivotal connection between one end of each of said bell cranks and one ci said armatures, a pivotal connection between the other ends of said 'bell cranks, a link connecting said pivotal connection with said switch member, a toggle having one end connected to said switch member and its other end connected to a iixed pivot, means operated by said bell cranks for holding said toggle in its made position when said switch member is in one position.
  • An electromagnetically operated switch comprising a movably mounted switch member, an operating coil, a pair of armatures for said coil extending into opposite ends of said coil and moving axially of said coil, a pair of bell crank arms mounted on stationary pivots, an operating connection between one end of each of said bell cranks and one of said armatures, an operating connection between the other ends of said bell cranks for causing said bell cranks to move in. unison upon energization oi' said coil, means biasing said armatures and bell cranks to their unattracted positions, and a link forming an operating connection between one arm of one of said bell crank arms and said switch member,
  • said link being in substantial alignment with said one arm when said switch member is in one position thereby to form a closed toggle with said one bell crank arm and secure said switch member in said position.
  • An electromagnetically operated switch comprising a movably mounted switch member, an
  • An electromagnetically operated switch comprising an operating shai't, a switch arm secured to said shaft, an operating arm secured to said shaft at an intermediate point of said arm, an operating coil, a pair of plunger armatures for said coil extending into opposite ends ofI said coil, a.
  • a switch comprising a switch member movable between open and closed circuit positions.
  • two toggles each having one end connected to said switch member to be movable in accordance with the movements of said switch member, and pivots iixad with reference to said switch member' for the other ends of said toggles, said toggles being arranged to be moved between made $0 and broken positions upon movement of said switch member between its open and closed circuit positions, and one of said toggles being in its made position in each of said switch member y positions thereby to secure said switch member 85 in said position.
  • a switch comprising a switch member movable between open and closed circuit positions. operating means for said switch member, a linkiage operatively connecting said operating means 40 with said switch member whereby said switch member is moved between open and closed circuit positions by said operating means, said linkage including a toggle having one end connected pivotally to be movable in accordance with the movements of salti switch member, and a second toggle having one end connected pivotally to said witch member for movement in accordance wl h the movements of said switch member and its other end mounted on a stationary pivot, the rst of said toggles being movable as part of said linkage for operation of said first toggle between its made and broken positions to move said switch member, and the second of said toggles being arranged to be in its made position when said rst toggle is in its broken position and in its broken position when said ⁇ first toggle is in its made position whereby said l 'switch member is secured in said positions.

Description

May 2, 1944. J. A. oPPEL ELECTRIC SWITCH Filed April 22, 1943 FIZ.
i I l I l l Inventor: John A.Oppel, 7vm7 -Iis Atborn.
Patented May 2, 1944 2,348,021 ELECTRIC SWITCH John A. Oppel, Upper Darby Township, Delaware County, Pa., assignor to General Electric Com pany, a corporation of New York Application April 22, 1943,'serial No. 483,978
(Cl. zoo-103) 9 Claims.
My Invention relates to switches, more particularly to electromagnetically operated switches, such as contactors, and has for its object a simple and reliable contactor which is automatically locked in both its open and closed circuit positions against operation by severe shocks.
In carrying out my invention `in one form, I utilize two toggle mechanisms, one of which is closed when the switch is open thereby to lock the circuit breaker in its open circuit position, and the other of which is closed to lock the circuit breaker when in its closed circuit position.
More specifically, I provide an operating electromagnet having a two-part plunger armature, together with two bell crank arms mounted on stationary central pivots and each having an end pivotally connected to an outerend of one of the plunger armatures, as described and claimed in a copending application, Serial No. 432,724, filed by John E. Lake on February 28, 1942, assigned to the same assignee as this application, and of which my invention is an improvement. The aforementioned application issued as Patent No. 2,336,871 on December 14, 1943. Also, a pivotal connection is provided between the other ends of the bell cranks, which connection is connected through a link to an arm connected to operate the switch mechanism. When the circuit breaker is closed, this link and one arm of one of the bell cranks forms a closed toggle locking the circuit breaker in its closed position, For locking the circuit breaker in its open position, a second toggle is provided having one end connected to the circuit breaker operating arm and its other end connected to a stationary pivot.
For a more complete understanding of my invention, reference should be had to the accompanying drawing, Fig. 1 of which is an elevation view showing a circuit breaker embodying my invention in its open circuit position; while Fig. 2 is a view similar to Fig. 1 but showing the circuit breaker in its closed circuit position.
Referring to the drawing, the circuit breaker or contactor in one Aform of my invention is operated by a magnet coil Il) having two plunger armatures II and I2 movable axially with respect to the coil toward and away from each other. The outer ends of these plungers are connected by pivotal connections I3 and I 4 to the ends of bell crank arms I5 and I6 having stationary central pivots I'I and I8. The other ends of the bell cranks are connected pivotally together by means of a pivot pin I9, the arm I6 having a slot for the pivot pin extending lengthwise of this arm of the bell crank and providing a loose connection betweenthe bell crank I6 and the pivot pin to provide for movement of the bell' open circuit position, as shown in Fig. 1, a toggle l5 21 is provided having its upper end connected by means of a pivot 28 to an extension 29 on the armr 24, This extension is on the side of the ,f shaft 25 opposite ,the pivot 23, At its lower end the toggle 21 is connected to a stationary pvot 30. A spring 3| coiled around the movable pivot 32 of this toggle biases the toggle to its broken position, as shown in Fig. 2.
Thus with the circuit breaker in its open circuit position, as shown in Fig. 1, a projection or operating'member 33 on the upper arm of the bell crank I6 has engaged the lower link of the toggle 21 and moved the toggle against its bias to its closed or made position, as shown in the drawing. This toggle 21, therefore, rigidly secures the arm 21 and the shaft 24 against turning movement and thereby secures the circuit breaker in its open circuit position.
When the coil I0 is energized to close the cir-f cuit breaker, the two plungers II and I2 are drawn magnetically` toward each other into the interior oi the coil, the two ends of the plungers preferably engaging each Yother when the plungers are in their fully attracted positions, as shown in Fig. 2. As the plungers are pulled toward each other, the bell cranks I5 and I6 are turned, respectively, in clockwise and counterclockwise directions about the stationary pivotsll and I8 to the positions shown in Fig. 2, and the toggle 21 is broken toward the left by the spring 3|. During this movement the pivot I 9 moves toward the left hand. as seenin the drawing, and
Stralghtens trie toggle formed by the link 22 and the upper arm of the bell crank I6, whereby the operating arm 24 and the shaft 25 are turned in a clockwise direction thereby to bring the movable contact into engagement with the stationary contact in the circuit breaker closed position. In this position the toggle formed by the link 22 and the upper arm of the bell crank I8 is in its closed or made position with the pivot pin It engaging the lower wall of the slot 20, whereby the arm 2| and the shaft 25 are rigidly locked or secured in this position. f
When the coil I is deenergized, the bell cranks are moved about their pivots to their open circuit positions, as shown in Fig. 2, by means of biasing springs 3| and 35 coiled around the pivots l1 and IB. During this movement the operating projection 33 engagesthe toggle 21 and straightens it to its made position against the bias of its spring 3|,as shown'inFig. 1. y
The movable contact 2| may be 'suitably secured to the shaft 25.n As shown, it is pivotally mounted in a U-shaped member 31 which, in turn, is secured by a. bracket 38 to the shaft. AA helical spring 39 is secured between the contact 2| and one side of the U-shaped support -whereby the contact nonally is biased against the other side of the support, as shown in Fig. 1. Preferably, the arrangement is such that the contact 2| engages the contact 26 before the plungers are in their fully attracted positions so that the final movement of the Iplungers moves the contact arm counterclockwise about its pivot on the support 31 thereby compressing somewhat the spring 33. This provides for wiping together of the contacts and assures that the contacts are held together even after substantial wear.
Pmi ably, s sh wn in Fig. 1 in dotted lines, I0 through est.; o i t for the puro assuring that the operating member 33 is held by the springs 3l and 35, which overpower the spring 3|, in position toward the right hand to hold the toggle 21 in its made or straightened position. In other words, this slot provides for movement if necessary of the upper arm of the bell crank I6 toward the right, as seen in Fig. 2,v
to straighten the toggle 21 after the arm 24 and shaft 25 have been moved to their open circuit positions. Suitable stops (not shown) are provided to aimit the movement of the toggle 21 to its fully madeposition, the stops preferably being on the toggle itself. Moreover,l the slot 40 provides for a small amount of movement of the pin I9 toward the left hand when the coil is energized whereby the member 33 is moved toward the left to provide for breaking of the toggle 21 by the spring 3l. In the closed position shown in Fig. 1, the pin I9 engages the upper wall of the slot 40 so that the link 22 forms with the upper arm of the bell crank I6 a solid toggle in its closed position.
'I'his contactor is completely shockproof in either its open circuit or closed circuit position by reason of the two toggles which securely hold it in each position. Moreover, the double plunger armature arrangement is in itself shockproof since the two plungers and I2 have equal masses and move in opposite directions. Moreover, in the closed position with the inner ends of the two plungers in engagement with each other as shown in Fig. 2, and the outer heads of the plungers spaced from the coil and its magnet frame, the coil and magnet frame have considerable freedom of movement during a shock with respect to the plungers themselves and without transmitting this shock movement to the plungers.
While I have shown a particular embodiment ci? my invention, it will be understood, of course, that I do not wish to be limited thereto since .many modifications may be made, and I therefore contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.
' What I claim as new and desire to secure by Letters Patent of the United States is:
1. A switch comprising a switch member movable between open and closed circuit positions, operating means for said switch member, a linkage operating connection including two bell cranks operatively connecting said 4operating means with said switch member whereby said switch member is moved between open and closed circuit lpositions by said operating means,l said linkage including a toggle having one end connected pivotally to be movable in accordance with the movements of said switch member and itsother end mounted on a stationary pivot, and y a second toggle having one end connectetLpivotally to said switch member for movement in accordance with the movements of said switch member and its other end mounted on a stationary pivot, said toggles being arranged to be moved between made and broken positions upon movement of said switch member between its open and closed circuit positions and one of said toggles being in its made position in each of said switch member positions thereby to secure said switch member in said position.
2. A switch comprising a switch member movable b tween open and closed circuit positions, coil, a pair of armatures movable usly by said coil, a linkage operating connection including two bell cranks operatively connecting said armatures with said switch member whereby said switch member is moved between open and closed circuit positions by said coil, said linkage including a toggle having one end vconnected pivotally to be movable in accordance with `the Vmovements of said switch member, and asecond toggle having one end connected pivotally to said switch member for movement in accordance withfthe movements oi' said switch member and its other end mounted on a stationary pivot, said toggles being arranged to be moved between made and broken positions upon movement of said switch member between its open and closed circuit positions and one of e said toggles being in its made position in each of said switch member positions thereby to secure said switch member in said positions.
3,'An velectromagnetically operated switch comprising a movably mounted switch member, an operating coil, a pair of armatures for said coil, a pair oi' bell crankl arms mounted on stationary pivots, a pivotal connection between one end of each oi' said bell cranks and one of said armatures, va pivotal connection between the other endsof said bell cranks, means connectinga't` least one of said bell cranks with said switch member, a toggle having one end conne cted to said switch member and its other end connected to a'xed pivot, and means for holding` said toggle in its made position when said switch memberis in one position.
4.. An elcctromagnetically operated switch comprising amovably mounted switch member, an operating coil, a pair of armatures for said coil extending into said coil and moving axially of said coil, a'pair of bell crank arms mounted on stationary pivots, a pivotal connection between one end of each of said bell cranks and one ci said armatures, a pivotal connection between the other ends of said 'bell cranks, a link connecting said pivotal connection with said switch member, a toggle having one end connected to said switch member and its other end connected to a iixed pivot, means operated by said bell cranks for holding said toggle in its made position when said switch member is in one position.
5. An electromagnetically operated switch comprising a movably mounted switch member, an operating coil, a pair of armatures for said coil extending into opposite ends of said coil and moving axially of said coil, a pair of bell crank arms mounted on stationary pivots, an operating connection between one end of each of said bell cranks and one of said armatures, an operating connection between the other ends of said bell cranks for causing said bell cranks to move in. unison upon energization oi' said coil, means biasing said armatures and bell cranks to their unattracted positions, and a link forming an operating connection between one arm of one of said bell crank arms and said switch member,
said link being in substantial alignment with said one arm when said switch member is in one position thereby to form a closed toggle with said one bell crank arm and secure said switch member in said position.
6. An electromagnetically operated switch comprising a movably mounted switch member, an
operating coil, a pair of armatures for said coil extending into opposite ends of said coil and moving axially of said coil, a pair of belllcrank arms mounted on stationary piv'ots, a pivotal connection between one end of each of said bell cranks and one of said armatures, a pivotal connection between the other ends of said bell cranks for causing said bell cranks to move in unison upon energization oi.' said coil. means biasing said armatures and bell cranks to their unattracted positions, a link forming an operating connection 'between one arm oi' one of said bell cranks and said switch member, said link being in substantial alignment with said one arm when said switch member is in one circuit controlling position thereby to form a closed toggle with said one arm and secure said switch members in said position, and a toggle having one end connected to said switch member and lits other end connected to a fixed pivot arranged to be in a substantially closed position when said switch member is in another circuit controlling position.
'1. An electromagnetically operated switch comprising an operating shai't, a switch arm secured to said shaft, an operating arm secured to said shaft at an intermediate point of said arm, an operating coil, a pair of plunger armatures for said coil extending into opposite ends ofI said coil, a. pair of bell crank arms mounted on stationary pivots adjacent opposite ends of said l coil, a pivotal connection between one end of each of said bell cranks and one of said armatures, a pivotal connection between the other ends of said bell cranks for causing said bell' cranks to move in unison upon ener-gization of said coll, means biasing said armatures and said bell cranks to their unattracted positions, a link forming an operating connection between one end of said operating arm and said pivotal connection between said bell cranks, said link beingsin alignment with said one arm of one of said bell cranks when said switch arm is in a closed circuit position thereby to form a substantially closed toggle with said one arm to secure said switch arm in said position, a toggle having one end connected to the other end of said operating arm, a fixed pivot for the other end of said toggle, spring means for biasing said toggle to a broken 1'5 position to provide for movement of said switch arm to its closed circuit position, and a member carried by one of said bell cranks for engaging said toggle when said bell cranks move to their unattracted positions thereby to substantially 2o close said toggle to secure said switch arm in its open circuit position. i
8. A switch comprising a switch member movable between open and closed circuit positions. two toggles each having one end connected to said switch member to be movable in accordance with the movements of said switch member, and pivots iixad with reference to said switch member' for the other ends of said toggles, said toggles being arranged to be moved between made $0 and broken positions upon movement of said switch member between its open and closed circuit positions, and one of said toggles being in its made position in each of said switch member y positions thereby to secure said switch member 85 in said position. i
9. A switch comprising a switch member movable between open and closed circuit positions. operating means for said switch member, a linkiage operatively connecting said operating means 40 with said switch member whereby said switch member is moved between open and closed circuit positions by said operating means, said linkage including a toggle having one end connected pivotally to be movable in accordance with the movements of salti switch member, and a second toggle having one end connected pivotally to said witch member for movement in accordance wl h the movements of said switch member and its other end mounted on a stationary pivot, the rst of said toggles being movable as part of said linkage for operation of said first toggle between its made and broken positions to move said switch member, and the second of said toggles being arranged to be in its made position when said rst toggle is in its broken position and in its broken position when said `first toggle is in its made position whereby said l 'switch member is secured in said positions.
,o JOHN a oPPEL.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2484358A (en) * 1945-12-22 1949-10-11 Ward Leonard Electric Co Relay
US2492762A (en) * 1944-08-23 1949-12-27 Gen Electric Electric switch
US2546053A (en) * 1948-09-01 1951-03-20 Gen Electric Electromagnet control device
US2778226A (en) * 1954-08-04 1957-01-22 Mclean Dev Lab Inc Electromagnetic trip

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2492762A (en) * 1944-08-23 1949-12-27 Gen Electric Electric switch
US2484358A (en) * 1945-12-22 1949-10-11 Ward Leonard Electric Co Relay
US2546053A (en) * 1948-09-01 1951-03-20 Gen Electric Electromagnet control device
US2778226A (en) * 1954-08-04 1957-01-22 Mclean Dev Lab Inc Electromagnetic trip

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