US2773154A - Electric switch - Google Patents

Electric switch Download PDF

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Publication number
US2773154A
US2773154A US535150A US53515055A US2773154A US 2773154 A US2773154 A US 2773154A US 535150 A US535150 A US 535150A US 53515055 A US53515055 A US 53515055A US 2773154 A US2773154 A US 2773154A
Authority
US
United States
Prior art keywords
switch
cam
arm
shunt
main
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US535150A
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English (en)
Inventor
Williams Ernest
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Priority to US535150A priority Critical patent/US2773154A/en
Priority to DEG20494A priority patent/DE1059534B/de
Priority to FR1159798D priority patent/FR1159798A/fr
Priority to CH345679D priority patent/CH345679A/de
Priority to JP2411856A priority patent/JPS33523B1/ja
Priority to GB28678/56A priority patent/GB812992A/en
Application granted granted Critical
Publication of US2773154A publication Critical patent/US2773154A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
    • H01H33/66—Vacuum switches
    • H01H33/666—Operating arrangements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/02—Details
    • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
    • H01H33/12—Auxiliary contacts on to which the arc is transferred from the main contacts
    • H01H33/121—Load break switches
    • H01H33/125—Load break switches comprising a separate circuit breaker
    • H01H33/126—Load break switches comprising a separate circuit breaker being operated by the distal end of a sectionalising contact arm
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
    • H01H33/66—Vacuum switches
    • H01H33/666—Operating arrangements
    • H01H33/6661—Combination with other type of switch, e.g. for load break switches

Definitions

  • This invention relates to an electric switch, and more particularly, to an electric switch having a shunt path around the switch whereby the switching duty is transferred from the contacts of the switch to an auxiliary switching device.
  • the shunt path comprises a vacuum switch device at which the load circuit is made and broken.
  • this form of electrical switch has the disadvantage in that the vacuum switch device continues to carry part of the load current after the contacts of the switch are fuily closed. That is, the vacuum switch device is subjected to the additional duty of carrying part of the load current after the contacts of the switch are fully ciosed aside from the duty of making and breaking the load. This additional duty requires that the vacuum switch device be larger and more costly than would be the case if it carried no load current after full closure of the contacts of the switch and performed the duty of only making or breaking load current.
  • it is a further object of this invention to provide an uncomplicated, reliable, and low cost switching arrangement comprising a main switch and an auxiliary switch and an operating mechanism for transferring the duty of making and breaking the load current from said main switch to said auxiliary switch.
  • My invention comprises an electrical apparatus having a main electrical switch and a switching duty shunt switch together with an operating mechanism for said switches for automatically opening said shunt switch when said main switch is in closed position.
  • My invention further comprises a switch operating mechanism including a switch arm having one end thereof movable through an arc, a pivoted cam having a notch formed therein, said notch disposed in said are and adapted to receive a portion of said arms one end to cause rotation of said cam as said arm is moved, said cam having two spaced concave surfaces separated by a convex surface, and a cam follower engageahle with said concave and convex surfaces to impart closing and opening movement to a movable contact member as said arm is moved.
  • a switch operating mechanism including a switch arm having one end thereof movable through an arc, a pivoted cam having a notch formed therein, said notch disposed in said are and adapted to receive a portion of said arms one end to cause rotation of said cam as said arm is moved, said cam having two spaced concave surfaces separated by a convex surface, and a cam follower engageahle with said concave and convex surfaces to impart closing and opening movement to a movable
  • Fig. 1 is a partly broken away side elevation view of a preferred form of my invention in the full open position.
  • Fig. 2 is a partly broken away bottom view of part of the operating mechanism of Fig. 1 when viewed in the direction of arrow 2 of Fig. 1.
  • Fig. 3 is a partly broken away front view of another part of the operating mechanism of Fig. 1 when viewed in the direction of arrow 3 of Fig. 1.
  • Fig. 4 is a partly broken away side elevation view similar to that of Fig. 1 except in an intermediate position wherein the auxiliary shunt contacts are closed while the main contacts are open.
  • Like reference numerals will be used throughout the various figures to indicate like parts.
  • a main electrical switch comprising a fixed main contact 1 and a movable switch blade or arm 2 carrying movable main contacts 3.
  • blade or arm 2 comprises a pair of identical oppositely positioned and spaced elongated strips 4. At their lower ends the strips 4 are interconnected by a bridge 5 having a terminal connected thereto for connecting a line 6 thereto. At their upper ends the strips 4 are interconnected by a pair of spaced pins 7 and 8.
  • the contacts 3 are formed on the inner facing sides of the strips 4 between the pins 7v and 8 and a pair of spring elements 9 cooperate with the pin 8 to permit the upper ends of strips 4 to be spread somewhat when receiving the fixed main contact 1 therebetween.
  • the arm 2 is pivotally mounted adjacent its lower end through a pair of insulating coupling members 10 and operating rods 11 between a pair of support brackets 12.
  • the upper ends of support brackets 12 are connected together by a bridge 13 and fixed contact 1 is insulatingly mounted on said bridge 13 by virtue of an insulating bushing 14.
  • the right-hand end of bushing 14 has a terminal thereon for connection of a conducting strip 15 thereto.
  • a shunt or auxiliary switch such as a vacuum switch device.
  • the vacuum switch per se constitutes no part of my invention andcomprises a movable spring urged lower contact or rod 21 and a relatively fixed spring urged upper contact or rod 22.
  • the opposite ends of rods 21 and 22- are positioned in a movable vacuum chamber 23 defined in part by an insulating material jacket 23' which in turn is enclosed in an outer support jacket 24.
  • the lower contact 21 is slidable within a bushing 41 threaded into the lower end of jacket 24, and is biased toward bushing 41 by a spring 42. Also, the lower contact 21 is sealed to an end closure cap 43 of jacket 23 as by brazing.
  • the upper contact 22 is sealed to a collar 44 as by brazing, and sealed or brazed to the collar 44 and an apertured cap 45 of the upper end of jacket 23' is an accordion or bellows-like metallic member 46.
  • the lower end of jacket 23' is made vacuum tight by brazed parts 21 and 43
  • the upper end of jacket 23 is made vacuum tight by brazed parts 45, 46, 44 and 22.
  • Another apertured cap 47 is superposed over cap 45, and is slidable with respect to the contact 22 while contact 22 is biased to its Fig. l illustrated position by a spring 48.
  • the upper end of jacket 24 has a terminal thereon which is in electrical contact with rod 22 as well as a conducting strip 25 which is electrically connected to conducting strip 15.
  • the lower end of jacket 2 has a hollow cylindrical cam carrying n ember 2s protruding therefrom.
  • the lower end of rod 21 extends into the cylinder 26 and has a slot 2'7 formed therein. In the slot is positioned a circular rotary can] follower 23.
  • Cam fol-lower 28 is rotatable about a pin 29 passing through opposite sides of rod 21 across slot 27. The extreme outer ends of pin 29 are guided in a pair of lengthwise extending slots 30 formed in the upper end of cylinder 25.
  • a pin 32 extending parallel to the pin 29 and disposed in the same plane as the two slots 3tpasses through opposite sides of the cylinder 2s adjacent the lower end thereof.
  • a rotary cam .33 is mounted on pin 32 between opposite sides of cylinder 26 within slots 31.
  • the pin 32 has a pair of collars 34 thereon which abut the opposite inner surfaces of the opposite sides of cylinder 26 and between collars 34 and cam 33 are positioned a pair of spring elements 35.
  • cam 33 protrudes beyond the lower end of cylinder 2s and has notch or slot 36 formed therein, and in the rear and bottom edges of cam 33 are formed generally semicircular concave notches or slots 37 and 32 ⁇ respectively which have radii generally equal to the radius of circular cam 23.
  • the central portion of notches 37 and 38 are removed from each other by about 90 and are separated from each other by a convex curved edge 39.
  • the prior practice has been to leave the shunt arcing duty switch in the closed position after the main switch has been closed.
  • Apparatus of the type illustrated in the drawing has been constructed wherein the main switch had a current carrying capacity or rating of 600 amperes, and the vacuum switch had a continuous current carrying capacity or rating of 160 amperes, and a current interrupting capacity or rating of 600 amperes. At such ratings, assuming that the full load current is just under 600 amperes and that the vacuum switch is not opened after the main switch is closed, the ratio of the resistance of the vacuum switch to the resistance of the main switch should not be less than 5:1.
  • the vacuum switch is continuously carrying just less than amperes, and at a ratio of less than 5:1 the vacuum switch would be required to continuously carry more than 100 amperes which is greater than its continuous current carrying rating.
  • the vacuum switch becomes overheated which causes destruction of or damage to the brazed seals thereof whereby the high vacuum is lost.
  • the ratio of the resistance of the vacuum switch to the resistance of the main switch can drop below 5:1 due to accumulation of dirt on the main switch or looseness between the contacts thereof.
  • the ratio of the resistance of the vacuum switch to the resistance of the main switch was about 10:1 whereby at full load current of just under 600 amperes the vacuum switch continuously carries about 55 amperes of current, assuming the vacuum switch is not opened after the main switch is closed.
  • the resistance of the main switch may increase to more than twice its initial value. This means that the ratio of the resistance of the vacuum switch to the resistance of the main switch will drop to below 5:1 whereby the vacuum switch continuously carries more than lOO amperes and becomes overheated.
  • the shunt arcing duty switch is opened after the main switch is closed so as to avoid the possibility of overloading of the shunt switch in the event a fault develops in the main switch.
  • the vacuum switch is required to carry part of the load current since two parallel paths for the load current are provided at said instant.
  • the current therethrough will be substantially greater than the continuous current carrying rating of the shunt switch.
  • these instances are of such short durations that insufficient time elapses for the shunt switch to become overheated.
  • An operating mechanism for an electrical apparatus comprising a pivotally mounted switch arm, one end of said arm having a pin thereon movable through an are when said arm is pivoted, a pivotally mounted cam, an open sided slot in said cam, the open side of said slot disposed in said arc, said pin engageable with said slot to cause pivotal movement of said cam, and two concave surfaces in said cam separated by a convex surface for imparting reciprocating motion to another member.
  • a switch operating mechanism comprising a pivotally mounted arm, an outer end of said arm movable through an are when said arm is pivoted, a fiat pivotally mounted cam having a notch formed in a peripheral edge portion thereof, said notch disposed in said are and adapted to receive a portion of said arm outer end to cause pivotal movement of said cam, another peripheral edge portion of said earn having a pair of concave surfaces formed therein separated by a convex surface, and a cam follower engageable with said concave and convex surfaces for imparting reciprocating motion to another member as said arm is pivoted.
  • mechanism for first closing said shunt switch as said main switch is actuated to closed position but before said main switch has reached closed position and then opening said shunt switch after said main switch has reached closed position comprising a pivotally mounted switch arm of said main swtich, an outer end of said arm movable through an arc as said arm is pivoted, a pivotally mounted cam having a notch formed in a peripheral edge portion thereof, a portion of said notch disposed in said are and adapted to receive a portion of said arm outer end as said arm is pivoted to cause pivotal movement of said cam, a pair of spaced concave surfaces formed in another peripheral edge portion of said cam separated by a convex surface of said another peripheral edge portion, and a cam follower engagcable with said concave and convex surfaces for imparting closing and opening movement to a movable contact member of said shunt switch as said arm is pivoted from open to closed position.

Landscapes

  • High-Tension Arc-Extinguishing Switches Without Spraying Means (AREA)
  • Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
US535150A 1955-09-19 1955-09-19 Electric switch Expired - Lifetime US2773154A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US535150A US2773154A (en) 1955-09-19 1955-09-19 Electric switch
DEG20494A DE1059534B (de) 1955-09-19 1956-09-07 Aus einem Hauptschalter und einem Nebenschalter bestehende elektrische Schalteinrichtung
FR1159798D FR1159798A (fr) 1955-09-19 1956-09-12 Interrupteur électrique
CH345679D CH345679A (de) 1955-09-19 1956-09-12 Elektrischer Last-Trennschalter mit einem Hilfsschalter
JP2411856A JPS33523B1 (de) 1955-09-19 1956-09-19
GB28678/56A GB812992A (en) 1955-09-19 1956-09-19 Improvements relating to electric switching devices

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US535150A US2773154A (en) 1955-09-19 1955-09-19 Electric switch

Publications (1)

Publication Number Publication Date
US2773154A true US2773154A (en) 1956-12-04

Family

ID=24133047

Family Applications (1)

Application Number Title Priority Date Filing Date
US535150A Expired - Lifetime US2773154A (en) 1955-09-19 1955-09-19 Electric switch

Country Status (6)

Country Link
US (1) US2773154A (de)
JP (1) JPS33523B1 (de)
CH (1) CH345679A (de)
DE (1) DE1059534B (de)
FR (1) FR1159798A (de)
GB (1) GB812992A (de)

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2870298A (en) * 1956-08-27 1959-01-20 Schwager Wood Corp Encapsulated vacuum insulated circuit breaker
US2872550A (en) * 1956-09-20 1959-02-03 Schwager Wood Corp High voltage circuit interrupting and isolating apparatus
US2920169A (en) * 1957-02-11 1960-01-05 Jennings Radio Mfg Corp Vacuumized electric switch
US2965734A (en) * 1958-08-07 1960-12-20 Allis Chalmers Mfg Co Current conductive spring bearing for vacuum switch contacts
US2966569A (en) * 1957-04-29 1960-12-27 Jennings Radio Mfg Corp Vacuum switch
US2975254A (en) * 1958-06-25 1961-03-14 Allis Chalmers Mfg Co Spring bearing for vacuumized electric devices
US2979588A (en) * 1958-12-09 1961-04-11 Jennings Radio Mfg Corp Vacuum switch
US2981813A (en) * 1958-07-21 1961-04-25 Jennings Radio Mfg Corp Vacuum switch
US2985737A (en) * 1959-09-21 1961-05-23 S & C Electric Co Circuit interrupter construction
US3021407A (en) * 1958-09-16 1962-02-13 Jennings Radio Mfg Corp Vacuumized electric switch
US3025375A (en) * 1960-04-04 1962-03-13 Gen Electric Electric circuit breaker having a sealed interrupting unit
US3163736A (en) * 1961-05-23 1964-12-29 S & C Electric Co High voltage gas type circuit interrupter
US3571543A (en) * 1968-09-30 1971-03-23 G & W Electric Speciality Co Multiple position vacuum interrupter switching device
US3646294A (en) * 1970-12-31 1972-02-29 Itt Switch
DE2934776A1 (de) * 1979-08-28 1981-03-12 Siemens AG, 1000 Berlin und 8000 München Mittelspannungslasttrennschalter.
US4757166A (en) * 1987-06-15 1988-07-12 Westinghouse Electric Corp. Vacuum interrupter with ceramic enclosure
WO2010136424A1 (fr) * 2009-05-26 2010-12-02 Areva T&D Sas Dispositif d'accrochage et de verrouillage interne a un interrupteur ou a un disjoncteur
RU2534757C2 (ru) * 2009-12-29 2014-12-10 Абб Текнолоджи Аг Выключатель среднего напряжения
US9679724B2 (en) * 2015-07-13 2017-06-13 Eaton Corporation Component for electric power system, and contact assembly and open air arcing elimination method therefor
FR3122283A1 (fr) * 2021-04-26 2022-10-28 Schneider Electric Industries Sas Système de coupure d’un appareil électrique
EP4195229A1 (de) * 2021-12-13 2023-06-14 Schneider Electric Industries SAS Stromunterbrechungsvorrichtung auf einer stromleitung mit einer vakuumlampe
US12293888B2 (en) * 2022-05-12 2025-05-06 Abb Schweiz Ag Medium voltage switching apparatus
EP4675659A1 (de) 2024-07-02 2026-01-07 Efacec Energia - Máquinas e Equipamentos Eléctricos S.A. Lasttrennschalter

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8318697D0 (en) * 1983-07-11 1983-08-10 Ass Elect Ind Interrupter/isolator assembly

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2341931A (en) * 1941-04-24 1944-02-15 Gen Electric Circuit maker and breaker
US2427792A (en) * 1942-02-25 1947-09-23 Lear Inc Preselection control device
US2469203A (en) * 1945-12-04 1949-05-03 Gen Electric Electric switch
US2480622A (en) * 1945-12-04 1949-08-30 Gen Electric Electric switch
US2514839A (en) * 1944-06-17 1950-07-11 Ite Circuit Breaker Ltd Broken back circuit breaker contact

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2341931A (en) * 1941-04-24 1944-02-15 Gen Electric Circuit maker and breaker
US2427792A (en) * 1942-02-25 1947-09-23 Lear Inc Preselection control device
US2514839A (en) * 1944-06-17 1950-07-11 Ite Circuit Breaker Ltd Broken back circuit breaker contact
US2469203A (en) * 1945-12-04 1949-05-03 Gen Electric Electric switch
US2480622A (en) * 1945-12-04 1949-08-30 Gen Electric Electric switch

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2870298A (en) * 1956-08-27 1959-01-20 Schwager Wood Corp Encapsulated vacuum insulated circuit breaker
US2872550A (en) * 1956-09-20 1959-02-03 Schwager Wood Corp High voltage circuit interrupting and isolating apparatus
US2920169A (en) * 1957-02-11 1960-01-05 Jennings Radio Mfg Corp Vacuumized electric switch
US2966569A (en) * 1957-04-29 1960-12-27 Jennings Radio Mfg Corp Vacuum switch
US2975254A (en) * 1958-06-25 1961-03-14 Allis Chalmers Mfg Co Spring bearing for vacuumized electric devices
US2981813A (en) * 1958-07-21 1961-04-25 Jennings Radio Mfg Corp Vacuum switch
US2965734A (en) * 1958-08-07 1960-12-20 Allis Chalmers Mfg Co Current conductive spring bearing for vacuum switch contacts
US3021407A (en) * 1958-09-16 1962-02-13 Jennings Radio Mfg Corp Vacuumized electric switch
US2979588A (en) * 1958-12-09 1961-04-11 Jennings Radio Mfg Corp Vacuum switch
US2985737A (en) * 1959-09-21 1961-05-23 S & C Electric Co Circuit interrupter construction
US3025375A (en) * 1960-04-04 1962-03-13 Gen Electric Electric circuit breaker having a sealed interrupting unit
US3163736A (en) * 1961-05-23 1964-12-29 S & C Electric Co High voltage gas type circuit interrupter
US3571543A (en) * 1968-09-30 1971-03-23 G & W Electric Speciality Co Multiple position vacuum interrupter switching device
US3646294A (en) * 1970-12-31 1972-02-29 Itt Switch
DE2934776A1 (de) * 1979-08-28 1981-03-12 Siemens AG, 1000 Berlin und 8000 München Mittelspannungslasttrennschalter.
US4757166A (en) * 1987-06-15 1988-07-12 Westinghouse Electric Corp. Vacuum interrupter with ceramic enclosure
WO2010136424A1 (fr) * 2009-05-26 2010-12-02 Areva T&D Sas Dispositif d'accrochage et de verrouillage interne a un interrupteur ou a un disjoncteur
FR2946180A1 (fr) * 2009-05-26 2010-12-03 Areva T & D Sa Dispositif d'accorchage et de verrouillage interne a un interrupteur ou a un disjoncteur.
US8581135B2 (en) 2009-05-26 2013-11-12 Schneider Electric Energy France Latching and locking device inside a switch or a circuit breaker
RU2529010C2 (ru) * 2009-05-26 2014-09-27 Шнейдер Электрик Энерджи Фрэнс Внутреннее захватное и блокирующее устройство для выключателя или прерывателя
RU2534757C2 (ru) * 2009-12-29 2014-12-10 Абб Текнолоджи Аг Выключатель среднего напряжения
US9679724B2 (en) * 2015-07-13 2017-06-13 Eaton Corporation Component for electric power system, and contact assembly and open air arcing elimination method therefor
FR3122283A1 (fr) * 2021-04-26 2022-10-28 Schneider Electric Industries Sas Système de coupure d’un appareil électrique
WO2022229553A1 (fr) * 2021-04-26 2022-11-03 Schneider Electric Industries Sas Système de coupure d'un appareil électrique
CN117256037A (zh) * 2021-04-26 2023-12-19 施耐德电气工业公司 用于中断电气器具的系统
EP4531068A3 (de) * 2021-04-26 2025-06-11 Schneider Electric Industries Sas Abschaltsystem für ein elektrisches gerät
US12658387B2 (en) 2021-04-26 2026-06-16 Schneider Electric Industries Sas Switching system of an electrical device
EP4195229A1 (de) * 2021-12-13 2023-06-14 Schneider Electric Industries SAS Stromunterbrechungsvorrichtung auf einer stromleitung mit einer vakuumlampe
US12293888B2 (en) * 2022-05-12 2025-05-06 Abb Schweiz Ag Medium voltage switching apparatus
EP4675659A1 (de) 2024-07-02 2026-01-07 Efacec Energia - Máquinas e Equipamentos Eléctricos S.A. Lasttrennschalter

Also Published As

Publication number Publication date
GB812992A (en) 1959-05-06
FR1159798A (fr) 1958-07-02
JPS33523B1 (de) 1958-01-31
DE1059534B (de) 1959-06-18
CH345679A (de) 1960-04-15

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