US1807020A - Operating meckanism - Google Patents

Operating meckanism Download PDF

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US1807020A
US1807020A US1807020DA US1807020A US 1807020 A US1807020 A US 1807020A US 1807020D A US1807020D A US 1807020DA US 1807020 A US1807020 A US 1807020A
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link
lever
solenoid
pin
members
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H3/00Mechanisms for operating contacts
    • H01H3/22Power arrangements internal to the switch for operating the driving mechanism
    • H01H3/30Power arrangements internal to the switch for operating the driving mechanism using spring motor

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  • V E NTORS Eosrvel/G Van SirK/e fi SfQn/ey TSqhof/e/d AT'i'ORNEY May 26, 1931.
  • Our invention relates to circuit interrupters and particularly to operating mechanisms therefor.
  • One object of our invention is to provide an operating mechanism for circuit interrupters which shall be trip-free in all its positions.
  • Another object of our invention is to provide an actuating mechanism for a circuit interrupter that shall employ a latch and a magnetically-operated trigger that are in separate fixed pivoted positions.
  • a further object of our invention isto provide an operating mechanism for a circuit interrupter that shall be reset after the release of the interrupter.
  • a still further object of our invention is to provide an actuating mechanism wherein the maximum. fierce exerted shall be efiective at the time of the maximum magnetic repulsion between the movable and stationary contact members.
  • Figure 1 is a view, partly in section and partly in elevation, of the particular embodiment of our invention in closed position.
  • Fig. 2 is a similar view, in elevation, in
  • Fig. 3 is a view similar to that in Figs. 1 and 2 but showing the breaker in complete open position.
  • Our invention is embodied in an operating mechanism 1 which comprises an actuating solenoid 2 and a tripping solenoid 3, thellatch 4 and the tri ger 5 of which are pivotally supported in iixed positions.
  • the solenoid 2 is mounted upon a bracket 6 that is the means for pivotally supporting an actuating member 7 on pin 8.
  • the actuating member 7 is connected by pin 9 and link 10 to the pin 11 that is pivoted to the moving core 12 of the solenoid mechanism 2.
  • the floating link 14 has latching means 15 and 16 at its opposite ends for retaining it in fixed position, as will be described more fully hereinafter.
  • the rocker lever 23 is rotatably supported on 7 the extension 24 of the casing of the member 2 by a pin 25.
  • the pin 26 reduces a downward pull, while pin 27, pro uces an upward pull.
  • the apparatus is so arranged that either of such pulls may be utilized to close it.
  • a spring member 28 is connected to the rocker lever 23 by a pin 29.
  • the member 28 is tensioned when the operating mechanism is in closed position and is employed to accelerate the rocker lever 23 to increase the speed of movement of the mechanism controlled thereby.
  • a bracket 31 on the solenoid mechanism 2 is the means for supporting the latch 4 in fixed pivotable position about a pin 32.
  • a spring 33 is employed to bias the latch 4 in clockwise rotation.
  • the latehin means 16, on the end of the floating lie 14 opposite to the latching means 15, comprises-a pin 35, a link 36 and a bell crank
  • the bell crank 37 is pivotally W0 supported on the bracket 6 by. a. pin 38 and is connected, at itsupper end, to link 36 by pin 39.
  • a spring member 40 coo rates with one arm of the bell crank 37 to bias it in a clockwise direction.
  • the tri ger 5 is pivoted to the trippingsolenoid 3 y a pin 44 and is biased in a counter-clockwise d rection by the spring mechanism 45.
  • a projection 46 on the trigger 5 cooperates with a rod 47 on the moving core of the said solenoid 3 and is the means, when the solenoid 3 is energized, for moving the trigger in a clockwise directiontorelease the latch 16.
  • a pin 48 on the actuating lever 7 supports one end of a link 49, the other end 0% which is pivotally supported on the pivotal member 51 by pin 54 and is the means for operating the mechanism 1 by hand.
  • the pivotal member 51 is supported, by pin 52 on the solenoid mechanism 2 and contains projections for pivotal pins 53 and 54, to-either of which the link 49 may be attached, depending upon the location of the'operating mechanism 1 below or above the circuit interrupter supporting structure.
  • a tensioned spring 55 is suspended between a projection '56 on the solenoid mechanism 2 and the end 57 of the actuating member toimpart a counter-clockwise movement to' the member 7 when the latch mechanism 15 is released.
  • a further clockwise movement of the floating link 14 releases the latching means 15, whereby the pin 13 becomes a floating pivot that permits the link 7 to move in a clockwise direction because of the tension in the spring member 55.
  • This movement causes the free end of the floating link 14 that supports the in ,5; to move downward,
  • an operat ing mechanism for a circuit interrupter that is trip-free in operation in all positions, and that employs a stationary pivotally supported latch and electrically actuated trigger so designed as to produce a high speed separation of the contact members.
  • a circuit-closing device the combination with two pivotally mounted members, of a floating link hingedly supported at one of its ends to one end of a pivotal member, latching means for-each end of the said floating link and a link member for uniting the floating member to the other said pivotal member.
  • a circuit-closing device the combination with two pivotally mounted members, of a floating link hingedly supportedat one of its ends to one end of a pivotal member and a pair of stationary pivoted latches for retaining theabove said members in fixed positionf Y 3.
  • a circuit-closing device the combination with two pivotally mounted members, of a floating link hingedly supported at one of its ends to one end of a pivotal member and a pair of latches in fixed pivotal position, one for releasably engaging one end of the said floating link in all positions except during tripping operation and the other to retain the entire mechanism in latched position.
  • a solenoid having pivotal means of support for a contact-carrying lever and for an actuating lever, of means for uniting the levers comprising a link and a floating lever and latching means for retaining the said floating lever in fixed relation with the actuating lever and with the solenoid.
  • a solenoid having pivotal means of support for a contact-carrying lever and for an actuating lever, of means for unit ing the levers comprising a link and a floa.t ing lever and latching means in fixed position on the solenoid for retaining the floating lever in fixed relation with the actuating lever and with the solenoid.
  • a solenoid having separate means of support for a contact-carrying lever and an actuating lever, of means for uniting the levers comprising a link and a floating lever and latching means for retaining the floating lever in fixed relation with the actuating lever and with the solenoid.
  • a circuit interrupter the combina-- tion with a solenoid having separate means of support for a contact-carrying lever and an actuating lever, of means for uniting the levers comprising a pair of hinged link members, the one link member having an extension, and a pair of fixed pivotal latch members, one of which engages the said extension retaining it in fixed position while the actuating lever is operated to move the other end of the said link into engagement with the other said latch.
  • a switching equipment inwhieli large .f currents are present resulting in a blow-out efiect produced when a circuit is be' completed by the bridging member coming incontact with the contact members; an operating mechanismcooperating therewith and a i system of levers so associatedwith the operating mechanism-that a maximum force is 'the said blow-out efiect.
  • ble contact members designed to carry heavy current and in which a blow-out eflect is producedwhen the said contact members touch on closing
  • an actuating mechanism for opmating the separable contact member a lever system cooperating with the actuating mechanism esigne to be trip free in all 0 its positions
  • lever system being char- 7 acterized by means to move the contact memher in a manner such as to provide a varying -meehanism, the combination with two -80 force that increases to a maximum substantially at the instant the contacts come into engagement and that decrease thereafter.
  • circuit-interrupter operating ivotally. mounted members, of a system of links for interconnecting-the said members and a supports for engaglingthe sai members whenw I inapredetermine I I p 18.
  • a circu t-interrupter operating:

Description

y ,6, 1931. R. C. VAN SICKLE ET AL 1,807,020
OPERATING MECHANISM FOR OIL CIRCUIT INTERRUPTERS Filed Dec. 9, 1927 3 Sheets-Sheet l.
IN V E NTORS Eosrvel/G Van SirK/e fi SfQn/ey TSqhof/e/d AT'i'ORNEY May 26, 1931. R. c. VAN SICKLE ET AL 1,807,020
OPERATING MECHANISM FOR OIL CIRCUIT INTERRUPTERS Filed Dec. 9, 1927 3 Sheets-Sheet 2 [NV E NTO R5 Eoswe/l 6. ha Sic/(l8 & S/vn/ey TSchof/e ld AT'ToRNEY May 26, 1931-. R. c. VAN SICKLE'ET AL 1,807,020
OPERATING MECHANISM FOR OIL CIRCUIT INTERRUPTERS Filed Dec. 9, 1927 5 Sheets-Sheet 3 INVENTORS. Boswel/ (2 [6n Sic/(la k Sfan/ey TSc/wf/e/d ATTORNEY Patented May 26, 1931 UNITED STATES PATENT OFFICE ROSWELL C. VAN SICKLE AND STANLEY T. SCHOFIELD, OF WILKINSBURG, PENNSYL- VANIA, ASSIGNORS TO WESTINGHOUSE ELECTRIC AND PANY, A CORPORATION OF PENNSYLVANIA MANUFACTURING COM- OPERATING MECHANISM FOR- OIL CIRCUIT INTERRUPTEBS Application filed December 9, 1927. Serial No. 238,756.
Our invention relates to circuit interrupters and particularly to operating mechanisms therefor.
One object of our invention is to provide an operating mechanism for circuit interrupters which shall be trip-free in all its positions.
- Another object of our invention is to provide an actuating mechanism for a circuit interrupter that shall employ a latch and a magnetically-operated trigger that are in separate fixed pivoted positions.
A further object of our invention isto provide an operating mechanism for a circuit interrupter that shall be reset after the release of the interrupter.
A still further object of our invention is to provide an actuating mechanism wherein the maximum. fierce exerted shall be efiective at the time of the maximum magnetic repulsion between the movable and stationary contact members.
In designing circuit interrupters, in the past, attention has always been paid to ebtaining some specific mechanical construction, such as trip-free protection, high speed of operation or strength of the various assembled levers.
According to our invention, we have proso vided a lever system for an operating mechanism that is trip-free, in. operation, throughout its entire movement and, at the same time, that produces a structure that will open with a high speed and that may be operated to close the circuit interrupter in an efficient manner in accordance with the following description.
Referring to the drawings, Figure 1 is a view, partly in section and partly in elevation, of the particular embodiment of our invention in closed position.
Fig. 2 is a similar view, in elevation, in
trip position immediately before the resetting of the trigger by gravity. 7
Fig. 3 is a view similar to that in Figs. 1 and 2 but showing the breaker in complete open position.
Our invention is embodied in an operating mechanism 1 which comprises an actuating solenoid 2 and a tripping solenoid 3, thellatch 4 and the tri ger 5 of which are pivotally supported in iixed positions.
1 The solenoid 2 is mounted upon a bracket 6 that is the means for pivotally supporting an actuating member 7 on pin 8. The actuating member 7 is connected by pin 9 and link 10 to the pin 11 that is pivoted to the moving core 12 of the solenoid mechanism 2.
A pin 13 on the end of the actuating mem ber 7 opposite to the end pivoted to the pin 8, supports a floating lever 14 that is pivoted thereon. The floating link 14: has latching means 15 and 16 at its opposite ends for retaining it in fixed position, as will be described more fully hereinafter.
A pin 18, located near the mid section of the floating link 14, pivotally supports the con necting link 21, the other end of this link being connected by pin} 22 to a rocker lever 23. The rocker lever 23 is rotatably supported on 7 the extension 24 of the casing of the member 2 by a pin 25. Pine 26 and 27, at the ends of the operating lever 23, are the means of applying the force produced by the mechanism 1 to the apparatus to be operated. The pin 26 reduces a downward pull, while pin 27, pro uces an upward pull. The apparatus is so arranged that either of such pulls may be utilized to close it.
A spring member 28 is connected to the rocker lever 23 by a pin 29. The member 28 is tensioned when the operating mechanism is in closed position and is employed to accelerate the rocker lever 23 to increase the speed of movement of the mechanism controlled thereby. I
A bracket 31 on the solenoid mechanism 2 is the means for supporting the latch 4 in fixed pivotable position about a pin 32. A spring 33 is employed to bias the latch 4 in clockwise rotation. The latchin means 15, comprising a projection on the oating link 14, engages a. projection 34 on the latch 4 and is the means for retaining the operating mechanism 1 in closed position when the solenoid mechanism 2 is operated.
The latehin means 16, on the end of the floating lie 14 opposite to the latching means 15, comprises-a pin 35, a link 36 and a bell crank The bell crank 37 is pivotally W0 supported on the bracket 6 by. a. pin 38 and is connected, at itsupper end, to link 36 by pin 39. A spring member 40 coo rates with one arm of the bell crank 37 to bias it in a clockwise direction. Arm 41 of the bell crank 37,
opposite to the one pivoted to the pin39,
supports, at itsend, a roller 42 that is designed to engage the re-entrant surface 43 of the magnetically-actuated trigger 5. By employing the bell crank 37 and the link 36, instead of directly latching the trigger 5 to the pin' 35, we are able to obtain a very light latching load which will require a very smal force to release. The tri ger 5 is pivoted to the trippingsolenoid 3 y a pin 44 and is biased in a counter-clockwise d rection by the spring mechanism 45. A projection 46 on the trigger 5 cooperates with a rod 47 on the moving core of the said solenoid 3 and is the means, when the solenoid 3 is energized, for moving the trigger in a clockwise directiontorelease the latch 16.
A pin 48 on the actuating lever 7 supports one end of a link 49, the other end 0% which is pivotally supported on the pivotal member 51 by pin 54 and is the means for operating the mechanism 1 by hand. The pivotal member 51 is supported, by pin 52 on the solenoid mechanism 2 and contains projections for pivotal pins 53 and 54, to-either of which the link 49 may be attached, depending upon the location of the'operating mechanism 1 below or above the circuit interrupter supporting structure.
A tensioned spring 55 is suspended between a projection '56 on the solenoid mechanism 2 and the end 57 of the actuating member toimpart a counter-clockwise movement to' the member 7 when the latch mechanism 15 is released.
Assuming the circuit interrupter to be in its closed position, asshown in Fig. 1', with the lug of the latching means 15 engaging .the
projection 34 of latch 4, and the roller 42 engaging the re-entrant surface 43 on 'the trigger 5, upon energizingthe solenoid 3, the upward movement of the rod 47 strikes against the projection 46 of the trigger 5, thereby turnmgit in a clockwise direction. The reentrant surface-'43 of the trigger 5 1s disengaged from the roller 42 and permits the bell crank 37 to turn in a counterclockwise direction, thus permitting the floatlng link 14 to move upward, rotating in a counterclockwise direction about the pin 13 and permit-- ting the rockerlever 23 to move because of the action of the spring 28, to open the circuit interrupter. A further clockwise movement of the floating link 14 releases the latching means 15, whereby the pin 13 becomes a floating pivot that permits the link 7 to move in a clockwise direction because of the tension in the spring member 55. This movement causes the free end of the floating link 14 that supports the in ,5; to move downward,
moving the be crank 37 first counterclockwise, then clockwise until such time as the roller onv arm 41 thereof engages the re-entrant surface 43 of the latch 5, as shown in Fig.3, at which time the mechanism is in its full-open position. s
In closing the circuit interrupter,-when the solenoid mechanism 2 is energized, as shown in Fig. 3, the moving core 12 is moved in a a downward direction carrying with it the actuating lever 7, the floating link 14 and the link 21, which movement causes a clockwise rotation of the operating lever 23.. The final movementof the'moving core member 12 will move the lug of the latching means 15 into cause the floating link 14 to be released and permit the circuit interrupter to open, even though the energization of the solenoid 2 continued. This protection during closingis known in the art as a trip-free feature and the mechanism is known as a. trip-free mech- I anism.
In designing the above-described operating mechanism, special attention was given to the change in the efiective length of the levers durin operation, in order that the pull ex-- erted y the mechanism 1 shallbe increased to a maximum at substantially the end of two thirds of its closing movement, this being substantially the time at which the bridging member first comes into engagement with the contact members. Thereafter, the change in the effective lengths ofthe levers diminishes the amount of pull exerted by the mechanism 1, thus preventing slamming-of'the moving parts at the end of the closing movement of the circuit interrupter. v a
It is well known in the circuit interrupter art that a magnetic force acts on the brid 'ng member when it engages the contact mem ers, this force being due to the efl'ect of the current traversing the said bridging member. In cirv cuits carrying large currents, this blowout effect becomes quite appreciable. .Heretofore, Y
the operating mechanisms for circuit inter-.- rupters were designed in such a manner that the pull tending to close the circuit interrupter was a maximum at the end of its closing movement. This was undesirable for, if
the solenoid'was of such strength as to insure a closurewhere heavycurrent was flowing in the circult, the final movement to closed position produced a slamming of the moving parts. If the force exerted by the closing mechanism reaches its maximumvalue-when 39 the bridging member comes into engagement with the contact members, suflicient force will be exerted to assure the complete engagement of the said members and the harmful slamming will be eliminated because thereafter the force diminishes in value. 'Our abovedescribed lever system operates to produce such a maximum pull as has just been described by the varying of the efl'ective length of the rocker lever 23 relative to the direction of the applied force through the link 21.
Accordingly, we have invented an operat ing mechanism for a circuit interrupter that is trip-free in operation in all positions, and that employs a stationary pivotally supported latch and electrically actuated trigger so designed as to produce a high speed separation of the contact members.
By employing our present link arrangement, we obtain an operating mechanism in which the maximum force is exerted at the time the maximum magnetic repulsion acts on the bridging member of the circuit interrupter. The bell crank link employed on the tripping lever avoids a direct trigger engagement with the said lever, thus eliminating heavy trigger loads and enabling the operating mechanism to be released at any position without the expenditure of a large amount of energy.
It is to be understood that such changes in the form, arrangement and connection of the component parts of our invention may be made as shall fall within the scope of the appended claims.
We claim as our invention:
1. In a circuit-closing device, the combination with two pivotally mounted members, of a floating link hingedly supported at one of its ends to one end of a pivotal member, latching means for-each end of the said floating link and a link member for uniting the floating member to the other said pivotal member.
2. In a circuit-closing device,the combination with two pivotally mounted members, of a floating link hingedly supportedat one of its ends to one end of a pivotal member and a pair of stationary pivoted latches for retaining theabove said members in fixed positionf Y 3. In a circuit-closing device, the combination with two pivotally mounted members, of a floating link hingedly supported at one of its ends to one end of a pivotal member and a pair of latches invfixed pivotal posi tion for engaging each end of the said floating link.
4. In a circuit-closing device, the combination with two pivotally mounted members, of a floating link hingedly supported at one of its ends to one end of a pivotal member and a pair of latches in fixed pivotal position, one for releasably engaging one end of the said floating link in all positions except during tripping operation and the other to retain the entire mechanism in latched position.
5. In a circuit interrupter, the combination with a solenoid having pivotal means of support for a contact-carrying lever and for an actuating lever, of means for uniting the levers comprising a link and a floating lever and latching means for retaining the said floating lever in fixed relation with the actuating lever and with the solenoid.
6. In a circuit interrupter, the combination with a solenoid having pivotal means of support for a contact-carrying lever and for an actuating lever, of means for unit ing the levers comprising a link and a floa.t ing lever and latching means in fixed position on the solenoid for retaining the floating lever in fixed relation with the actuating lever and with the solenoid.
7. In a circuit interrupter, the combination with a solenoid having separate means of support for a contact-carrying lever and an actuating lever, of means for uniting the levers comprising a link and a floating lever and latching means for retaining the floating lever in fixed relation with the actuating lever and with the solenoid.
8. In a circuit interrupter, the combina-- tion with a solenoid having separate means of support for a contact-carrying lever and an actuating lever, of means for uniting the levers comprising a pair of hinged link members, the one link member having an extension, and a pair of fixed pivotal latch members, one of which engages the said extension retaining it in fixed position while the actuating lever is operated to move the other end of the said link into engagement with the other said latch.
9. The combination with anactuating device, of a pair of levers pivoted thereto, a-
11. The combination with an actuating device, of a pair of levers pivoted thereto on separate supporting members, a pair of connectedlinks joining the said levers, a stationary pivotal latch, and an electrically-actuatedstationary pivotal trigger for releasing the levers in any of their positions.
12. In a circuit interrupter, thecombination with an operating mechanism and sep-,
arable contact-carrying members, of a lever system cooperating with the contact carrying members and actuated by said operating mechanism and means in the said lever sysv duced when the said contact members touch. v: 1'
' a a v plurality of retaining means ivoted to fixed tem to vary the efiective' leng th order that the maximum force exerted b the operating mechanism occurs substantia y at his the time the said contact members touch.
13.. A switching equipment inwhieli large .f currents are present resulting in a blow-out efiect produced when a circuit is be' completed by the bridging member coming incontact with the contact members; an operating mechanismcooperating therewith and a i system of levers so associatedwith the operating mechanism-that a maximum force is 'the said blow-out efiect.
14.- A switching equipment in which large currents'are present resulti in 'a blow-out effect produced when a circuit is being completedby the bridging member coming in contact with the contact members, an operatducingla maximum force su stantially at the v I time t 16. In a switch mechanism-having separa-' ing mechanism cooperatgg system of levers associa ing mechanism that vary in efiective ength with relation to the effort exerted by the operatin therewith, and awith the o eratproduced substantially at the of mechanism for producing a maxiv mum orce substantially at the instant of conf tact between the bridging member and the t said contact members. v
15. .In a switch mechanism having separa- 1 ble contact members. designed to carry heavy current andin which a blow-out efiect is proon closing,an actuating mechanism for operating the separable contact member, a lever system cooperating with the actuating mechanism characterized b means-tor pro e said contact members touch.
. ble contact members designed to carry heavy current and in which a blow-out eflect is producedwhen the said contact members touch on closing, an actuating mechanism for opmating the separable contact member, a lever system cooperating with the actuating mechanism esigne to be trip free in all 0 its positions, and lever system being char- 7 acterized by means to move the contact memher in a manner such as to provide a varying -meehanism, the combination with two -80 force that increases to a maximum substantially at the instant the contacts come into engagement and that decrease thereafter.-
17. In a circuit-interrupter operating ivotally. mounted members, of a system of links for interconnecting-the said members and a supports for engaglingthe sai members whenw I inapredetermine I I p 18. In. a circu t-interrupter operating:
. mechanism, 11116 m ination with twopiv tes osition.
,otally mounted members, of means for inter connecting the said members and 'a pair or, f
' latchespivoted to fixed supports for engagmg the said members when in a predetermined position.
5th day of Decem-
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2523116A (en) * 1944-01-14 1950-09-19 Westinghouse Electric Corp Control mechanism for circuit breakers
US2647182A (en) * 1950-08-05 1953-07-28 Westinghouse Electric Corp Circuit breaker mechanism

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2523116A (en) * 1944-01-14 1950-09-19 Westinghouse Electric Corp Control mechanism for circuit breakers
US2647182A (en) * 1950-08-05 1953-07-28 Westinghouse Electric Corp Circuit breaker mechanism

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