US2689895A - Electric circuit breaker with spark sealed casing - Google Patents

Electric circuit breaker with spark sealed casing Download PDF

Info

Publication number
US2689895A
US2689895A US331769A US33176953A US2689895A US 2689895 A US2689895 A US 2689895A US 331769 A US331769 A US 331769A US 33176953 A US33176953 A US 33176953A US 2689895 A US2689895 A US 2689895A
Authority
US
United States
Prior art keywords
casing
contacts
portions
plunger
circuit breaker
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
US331769A
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English (en)
Inventor
Richard C Ingwersen
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.)
Mechanical Products Inc
Original Assignee
Mechanical Products Inc
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
Priority to NL90626D priority Critical patent/NL90626C/xx
Priority to NLAANVRAGE7608169,A priority patent/NL181352B/xx
Application filed by Mechanical Products Inc filed Critical Mechanical Products Inc
Priority to US331769A priority patent/US2689895A/en
Priority to FR1086464D priority patent/FR1086464A/fr
Priority to DEM19518A priority patent/DE1017695B/de
Priority to GB21522/53A priority patent/GB735549A/en
Priority to ES0210942A priority patent/ES210942A1/es
Priority to CH313048D priority patent/CH313048A/fr
Application granted granted Critical
Publication of US2689895A publication Critical patent/US2689895A/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
    • H01H73/00—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism
    • H01H73/60—Protective overload circuit-breaking switches in which excess current opens the contacts by automatic release of mechanical energy stored by previous operation of a hand reset mechanism cartridge type, e.g. screw-in cartridge

Definitions

  • T-his invention relates to electriecircuit breakers of the kindv which comprise a split .casing structure enclosingxed; and movable contacts, with-.the movable contacts being electrically connectedfwith a thermal latch device, which device is operative toA release the movablecontacts.to4 InoveV rapidly andgtutomatically toopen position ⁇ upon the occurrence of.'Gulf-:rentv overload or a short circuit. More ⁇ particularly, the invei'itionA relates to plug type thermalcircuit pro,tectorSfy foruse in a standard, Edison base iguseholder to,
  • the present invention is concerned withk acircuit breaker of. the above kind in. which the iixed and; movable contacts are located within a portion of the split casing. interior so that the electrical. arc: lecon.- centrated in such interior casing portion and comesinto contact with such. portion ot the. metal contactsv and their conductor strips as it; is not practically possible to. shieldk from the electrical arc.
  • arcing Voccursthisfgiveszrise to internal pressure Ywhich .tends to' ⁇ burst openthesplit casing so thatythe arcevolved gases/tend to flow towards the casing splits and carryzwitgh.
  • Fig. 1 isf a. perspective View of an electric cir-V cuit breaker. in accordance with the invention.
  • lig ⁇ - 2 isan. elevational view looking upon the;
  • Fig. 3 is a Alongitudinal. section of. a. circuit breaker and .casing assembly accordingto Fig. 2 but with. the parts completely assembled and taken ina plane corresponding to the line rtf-a in Fig. 2, the ⁇ contacts, thermal latch andl plunger partsfbeing shown in elevation,
  • Fig. 4 ⁇ is atransverse section on the line b-b OfEig: 2.,.
  • Figs.. 5; andl 6 are. transverse sections on the lines-cf-c and tif-lt,,respectivelys ofyEig. 2, with the thermal latch and l associated parts removed,
  • Fig. '7 is a detail view, illustrating the sealing washer with diametral side split sealing iinger portions
  • Fig. 8 is a perspective cut-away View of this circuit breaker, with the contacts closed, and
  • Fig. 9 is a similar View to Fig. 8 but with the contacts open.
  • the casing construction is shown composed of two similar semi-cylindrical casing sections I and 2 of insulating material, which sections when the casing sections are assembled together represente diametrically opposite longitudinally extending splits 3 on the opposite sides o1 the cylindrical casing, the casing sections being held in assembled relationship by a pair of end caps, indicated generally at 4 and 5.
  • the casing sections combine to form an enclosed interior chamber indicated generally at 6, in which there are mounted a pair of diametrically spaced fixed contacts l, and in which chamber there is also mounted a thermal latch and movable contact unit, indicated generally at 8, and an actuator plunger 9.
  • the unit comprises a thermal latch assembly presenting oppositely disposed substantially U-shaped bimetallic latch parts II) united by integral bridge portions II, upon which portions the movable contacts I2 are mounted for engagement with their companion iixed contacts l.
  • the fixed contacts 'I and movable contacts I2 are located within an end portion 3a of the chamber E disposed adjacent the casing end wall 23 having the central opening 22 through which the actuator plunger 9 extends.
  • An opening ib in the end cap Il provides for the passage oi the plunger with all round clearance, as seen in Figs. 1 and 3.
  • the unit Il is slidable relatively to the plunger 9, with the latch parts Ii] being located upon opposite sides of the plunger and being adapted to have releasable latching engagement with abutment ledges I3 (Figs. 2, 8 and 9) secured ⁇ upon the plunger.
  • abutment ledges I3 Figs. 2, 8 and 9 secured ⁇ upon the plunger.
  • These ledges are preferably provided by separate metal L.shaped parts secured upon the plunger 9, as by a rivet I4.
  • the unit 8 is held stressed into engagement with the abutment ledges I3 by the action of a pair of coil springs I5 connected between the bridge portions II and laterally protruding ears I6 at the inner end of the plunger. These springs are stressed when the unit 8 is moved relatively to the plunger 9 to engage the bimetallic latch parts I0 with their abutment ledges I3 as seen in Figs. 2, 3 and 8. It is to be noted that the parts Ill are electrically conductive. ⁇ When the contacts II and I2 are closed, and the circuit breaker is in circuit, the current ilow takes piace between the contacts, in series along the limbs of the U -shaped latch parts I0.
  • the plunger 9 is itself biased by a coil spring I8, which spring is compressed when'the latch parts Ill are engaged with their abutment ledges I3, but acts immediately to project the end I9 of the plunger farther out of the corresponding casing end when the latch parts I0 are disengaged from the ledges I3 as seen in Fig. 9..
  • Such disengagement takes place automatically, due to the bimetallic nature of the latch parts I0 and their distortion under the influence of the heat of the conducted current, and will oc- 4 cur when the current reaches a predetermined value, above that for which the bimetallic parts I0 have been calibrated, which calibration may be, for example, 15, 20, 25 or 30 amperes.
  • the plunger is provided with a band portion 20, which extends outside the casing when the plunger end I9 is projected, as stated, and by being distinctively colored, for example, serves to give a visible indication that the circuit, controlled by the circuit breaker, has been broken.
  • Fixedly mounted upon the plunger there is a washer 2
  • An additional seal is provided by a washer 24 retained between the casing end wall 23 and the end cap 4.
  • a further seal is provided by a second sealing washer 25 having a disc portion mounted upon the washer 24 and formed with integral diametral finger portions 21 which are deformed to extend along and cover the portions of the longitudinal casing splits 3 which lie within the confines of the side flange 4a of the end cap 4. It is important to note that the flange 4a of the end cap 4 completely embraces that portion-of the casing which contains the chamber 6a in which the fixed and movable contacts are located and in which'arcing occurs.
  • the diametral linger portions 21 of the sealing washer 25 extend the entire extent of the inside of the end cap flange 4a and are deformed by this flange into firm and sealing engagement with respect to the portions of the longtiudinal casing splits 3 embraced by said cap flange.
  • These finger portions 25 seal the casing slits against the possible egress of gases, resulting from arcing, and thereby prevent these gases, with metal particles carried thereby, from forming an electrically conductive path with the end cap 4.
  • the sealing washers 24 and 25 could be formed in one, if desired, and are conveniently formed from vulcanized fibre material. When formed in one the disc portion of the washer may be relatively rigid, the finger portions 21, however, being capable of deformation into their required sealing position over the said portions of the casing splits 3 when the end cap 4 is applied, as will be understood.
  • the end cap 4 is deformed inwardly at its inner end to permanently embrace the casing shoulder 25, as indicated at 26, this shoulder being located on the casing beyond the said chamber portion 6a.
  • the other end cap 5 is shown formed with a screw threaded skirt portion 21, screwed into position upon the corresponding screw threaded end portion 28 of the combined casing sections, and adapted for screwing into operative position with respect to a socket (not shown) containing the main electric supply terminals of the circuit to which the circuit breaker is required to be applied, and with which supply terminals electrical connection is maintained by a terminal end cap 29.
  • the casing sections I and 2 along their longitudinally opposed edge surfaces, are formed with complementary, elongated recesses 30, which define longitudinally extending channels 3l in which electrical conductor vstri-ps 32 and 433 I are :ac-v commodated, the conductor .33 being 'in -electrical conducting -relationship tothe terminal end cap 29, and the other conductor strip 3.2 'bei-ng in electrical conducting relationship with-respect to ⁇ the screwed cap portion 21.
  • the fixed contacts .1 vare carried upon Aend portions 3d of rthe conductor strips which are bent inwardly in opposite 4directions into substantially arcuate form, as shown in Figs. 4, 8 vand 9 to dispose their xed contacts 'I in diametrically spaced relationship and AVas remotely as possible from the casing split 13. It is also to be noted with respect vto Figs. 4 land. '5, in particular, that the casing interior is formed with inwardly projected wall portions 35 which present wall surfaces 36 in proximity to the curvedly bent portions 31 of the conductor strip portions 34.
  • casing wall portions S35 and their wall surfaces 36 are of particular importance and serve the purpose of protecting the portions 31 of ⁇ the conductor strips from the direct eect of the arc which occurs when the circuit is suddenly interrupted at the contacts 1 and I2.
  • this varc will tend to follow a substantially circular or magnetic loop-like path in which the conductor strip portions (t1 are located.
  • the wall surfaces Sii are Yalso located in said path, immediately ahead of their respective conductor strip portions 31 and, accordingly, said wall surfaces serve as baffles to prevent the arc name or flash from striking against the otherwise exposed conductor strip portions and causing erosion thereof. That this is so has been proven in practice, by observing the occurrence of fscorching upon these wall surfaces upon arcing occurring.
  • the disc portions of the sealing washers24 and 25., or the single .disc portion if the separate washer: 24 is dispensedwith, are formed with central openings 2.9 through which the plunger e9 is able to have a sliding t. These washers, however, extend completely over the :diametral splits formed in the casing end wall 2.2i and thus seal these splits upon the outside of said end wall.
  • , on the plunger t is shownin Fig. 4 as being of substantially.rectangularshape and as providing surface portionswhich will cornpletely cover the inner end lof the Aopening 22 provided for the passage of the plunger 9. and presented to the interior of said casing lchamber portion Ea.
  • this washer 2l will be spaced inwardly from the said opening 22.
  • the action ofthe springs Yi5 upondisengagement of the thermal latch parts IB is so rapid that the washer 2 I lreaches the opening 22 to seal the same at the time'when arcing occurs due to breaking of the controlled circuit yat the ⁇ contacts 1 and I2.
  • an electric circuit breaker having a hollow casing formed by separate casing sections held assembled together by exteriorly applied end cap means, and including fixed and movable electrical contacts enclosed within a portion of said casing interior and circuit breaker mechanism operative to suddenly open the controlled circuit at said contacts upon the occurrence of current overload, whereby arcing occurs within the said casing portion at said contacts, the provision of means for sealing the end cap means with respect to the arc flame and evolved gases, said casing portion including an end wall with a diametral split and longitudinal splits on opposite sides of the casing portion and said end cap means including an end cap with a side flange completely embracing said casing portion and with an end wall covering said casing end wall, said sealing means including a portion covering said longttudinal casing splits, said sealing means being held enclosed upon the said casing portion by said end cap.
  • said sealing means comprising an end portion mounted upon the outside surface of said casing end Wall and covering the diametral split in said end Wall and iinger portions extending from the outer periphery of said disc portions at diametrically opposite portions thereof, said iinger portions closing the portions of the longitudinal casing splits included within said end cap iiange, said nger portions being deformed into sealing engagement over said longitudinal casing splits by the application of said end cap to the said casing,
  • an electric circuit breaker comprising a hollow cylindrical casing formed by separate casing sections forming the casing with a diametral split across one end wall thereof and longitudinal splits extending along opposite sides of the casing, and including fixed and movable contacts enclosed Within a chamber portion of said casing which includes said casing splits, and circuit breaker mechanism connected to suddenly open the controlled circuit at said contacts upon the occurrence of current overload, whereby arcing occurs Within said chamber portion at the contacts, said casing having an end cap retaining portion defined on its exterior surface and including an end cap firmly embracing the end portion of the casing which includes said chamber portion, said end cap having an end wall covering the said casing end wall and a side ange which completely embraces the portion of said casing containing said chamber portion and is held secured upon the outside of the casing by the engagement of the flange with said dened end cap retaining casing portion, the provision of means sealing said casing splits with respect to the interior of said chamber portion, said sealing means being conned upon the exterior of said casing
  • an electric circuit breaker including a split casing with xed and movable contacts mounted within the casing and thermal means connected with the movable contacts so as to break the circuit at said contacts upon the occurrence of current overload or a short circuit, said casing having an exteriorly applied metal end cap holding the split casing together, the provision of insulating means over the casing splits and between the casing and said end cap, said insulating means preventing the end cap from forming an electrically conductive path with gases evolved within the casing upon arcing occurring when the current is suddenly interrupted at said contacts.

Landscapes

  • Breakers (AREA)
  • Thermally Actuated Switches (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
US331769A 1953-01-19 1953-01-19 Electric circuit breaker with spark sealed casing Expired - Lifetime US2689895A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
NL90626D NL90626C (enrdf_load_stackoverflow) 1953-01-19
NLAANVRAGE7608169,A NL181352B (nl) 1953-01-19 Heugellier.
US331769A US2689895A (en) 1953-01-19 1953-01-19 Electric circuit breaker with spark sealed casing
FR1086464D FR1086464A (fr) 1953-01-19 1953-07-24 Disjoncteur électrique avec verrou à commande thermique
DEM19518A DE1017695B (de) 1953-01-19 1953-07-28 Elektrischer Selbstschalter
GB21522/53A GB735549A (en) 1953-01-19 1953-08-04 Improvements in and relating to electric circuit breakers
ES0210942A ES210942A1 (es) 1953-01-19 1953-08-21 Un interruptor de circuito eléctrico
CH313048D CH313048A (fr) 1953-01-19 1953-11-05 Disjoncteur électrique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US331769A US2689895A (en) 1953-01-19 1953-01-19 Electric circuit breaker with spark sealed casing

Publications (1)

Publication Number Publication Date
US2689895A true US2689895A (en) 1954-09-21

Family

ID=23295297

Family Applications (1)

Application Number Title Priority Date Filing Date
US331769A Expired - Lifetime US2689895A (en) 1953-01-19 1953-01-19 Electric circuit breaker with spark sealed casing

Country Status (7)

Country Link
US (1) US2689895A (enrdf_load_stackoverflow)
CH (1) CH313048A (enrdf_load_stackoverflow)
DE (1) DE1017695B (enrdf_load_stackoverflow)
ES (1) ES210942A1 (enrdf_load_stackoverflow)
FR (1) FR1086464A (enrdf_load_stackoverflow)
GB (1) GB735549A (enrdf_load_stackoverflow)
NL (2) NL181352B (enrdf_load_stackoverflow)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3014105A (en) * 1959-06-29 1961-12-19 Therm O Disc Inc Thermostatic controls
US3023292A (en) * 1958-10-01 1962-02-27 Gen Electric Electric circuit interrupter
US3868614A (en) * 1971-07-06 1975-02-25 Aiken Ind Inc Improved circuit breaker trip mechanism
US20060109073A1 (en) * 2004-11-23 2006-05-25 Mechanical Products Circuit breaker
US20100305565A1 (en) * 2000-08-01 2010-12-02 Arqos Surgical, Inc. Voltage threshold ablation apparatus
US8323280B2 (en) 2011-03-21 2012-12-04 Arqos Surgical, Inc. Medical ablation system and method of use
US9204918B2 (en) 2011-09-28 2015-12-08 RELIGN Corporation Medical ablation system and method of use
US9247983B2 (en) 2011-11-14 2016-02-02 Arqos Surgical, Inc. Medical instrument and method of use
US9585675B1 (en) 2015-10-23 2017-03-07 RELIGN Corporation Arthroscopic devices and methods
US9603656B1 (en) 2015-10-23 2017-03-28 RELIGN Corporation Arthroscopic devices and methods
US9681913B2 (en) 2015-04-21 2017-06-20 RELIGN Corporation Arthroscopic devices and methods
US10004556B2 (en) 2013-05-10 2018-06-26 Corinth MedTech, Inc. Tissue resecting devices and methods
US10022140B2 (en) 2016-02-04 2018-07-17 RELIGN Corporation Arthroscopic devices and methods
US10595889B2 (en) 2016-04-11 2020-03-24 RELIGN Corporation Arthroscopic devices and methods
US11065023B2 (en) 2017-03-17 2021-07-20 RELIGN Corporation Arthroscopic devices and methods
US11172953B2 (en) 2016-04-11 2021-11-16 RELIGN Corporation Arthroscopic devices and methods
US11207119B2 (en) 2016-03-11 2021-12-28 RELIGN Corporation Arthroscopic devices and methods
US11426231B2 (en) 2017-01-11 2022-08-30 RELIGN Corporation Arthroscopic devices and methods
US12167888B2 (en) 2016-03-10 2024-12-17 RELIGN Corporation Arthroscopic devices and methods

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2912546A (en) * 1958-05-02 1959-11-10 Texas Instruments Inc Electrical switch structures

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2585068A (en) * 1947-02-28 1952-02-12 Morris B Wood Electrical circuit breaker

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2476648A (en) * 1945-06-04 1949-07-19 Square D Co Circuit breaker
US2514545A (en) * 1946-07-11 1950-07-11 Mechanical Products Inc Circuit breaker
NL79693C (enrdf_load_stackoverflow) * 1952-05-24

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2585068A (en) * 1947-02-28 1952-02-12 Morris B Wood Electrical circuit breaker

Cited By (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3023292A (en) * 1958-10-01 1962-02-27 Gen Electric Electric circuit interrupter
US3014105A (en) * 1959-06-29 1961-12-19 Therm O Disc Inc Thermostatic controls
US3868614A (en) * 1971-07-06 1975-02-25 Aiken Ind Inc Improved circuit breaker trip mechanism
US20100305565A1 (en) * 2000-08-01 2010-12-02 Arqos Surgical, Inc. Voltage threshold ablation apparatus
US8333763B2 (en) 2000-08-01 2012-12-18 Arqos Surgical, Inc. Voltage threshold ablation apparatus
US20060109073A1 (en) * 2004-11-23 2006-05-25 Mechanical Products Circuit breaker
US7310041B2 (en) 2004-11-23 2007-12-18 Mp Hollywood Llc Circuit breaker
US8323280B2 (en) 2011-03-21 2012-12-04 Arqos Surgical, Inc. Medical ablation system and method of use
US10292751B2 (en) 2011-03-21 2019-05-21 RELIGN Corporation Medical ablation system and method of use
US11712282B2 (en) 2011-03-21 2023-08-01 RELIGN Corporation Medical ablation system and method of use
US9277954B2 (en) 2011-03-21 2016-03-08 Arqos Surgical, Inc. Medical ablation system and method of use
US9204918B2 (en) 2011-09-28 2015-12-08 RELIGN Corporation Medical ablation system and method of use
US9592085B2 (en) 2011-09-28 2017-03-14 RELIGN Corporation Medical ablation system and method of use
US11229477B2 (en) 2011-09-28 2022-01-25 RELIGN Corporation Medical ablation system and method of use
US11672586B2 (en) 2011-09-28 2023-06-13 RELIGN Corporation Medical ablation system and method of use
US9795434B2 (en) 2011-09-28 2017-10-24 RELIGN Corporation Medical ablation system and method of use
US10342603B2 (en) 2011-11-14 2019-07-09 RELIGN Corporation Medical instrument and method of use
US9247983B2 (en) 2011-11-14 2016-02-02 Arqos Surgical, Inc. Medical instrument and method of use
US10004556B2 (en) 2013-05-10 2018-06-26 Corinth MedTech, Inc. Tissue resecting devices and methods
US10582966B2 (en) 2015-04-21 2020-03-10 RELIGN Corporation Arthroscopic devices and methods
US9681913B2 (en) 2015-04-21 2017-06-20 RELIGN Corporation Arthroscopic devices and methods
US9603656B1 (en) 2015-10-23 2017-03-28 RELIGN Corporation Arthroscopic devices and methods
US9585675B1 (en) 2015-10-23 2017-03-07 RELIGN Corporation Arthroscopic devices and methods
US12023090B2 (en) 2015-10-23 2024-07-02 RELIGN Corporation Arthroscopic devices and methods
US10568685B2 (en) 2015-10-23 2020-02-25 RELIGN Corporation Arthroscopic devices and methods
US11234759B2 (en) 2015-10-23 2022-02-01 RELIGN Corporation Arthroscopic devices and methods
US11419670B2 (en) 2015-10-23 2022-08-23 RELIGN Corporation Arthroscopic devices and methods
US10327842B2 (en) 2015-10-23 2019-06-25 RELIGN Corporation Arthroscopic devices and methods
US11771456B2 (en) 2016-02-04 2023-10-03 RELIGN Corporation Arthroscopic devices and methods
US10022140B2 (en) 2016-02-04 2018-07-17 RELIGN Corporation Arthroscopic devices and methods
US12167888B2 (en) 2016-03-10 2024-12-17 RELIGN Corporation Arthroscopic devices and methods
US11207119B2 (en) 2016-03-11 2021-12-28 RELIGN Corporation Arthroscopic devices and methods
US12096969B2 (en) 2016-03-11 2024-09-24 RELIGN Corporation Arthroscopic devices and methods
US11622784B2 (en) 2016-04-11 2023-04-11 RELIGN Corporation Arthroscopic devices and methods
US11172953B2 (en) 2016-04-11 2021-11-16 RELIGN Corporation Arthroscopic devices and methods
US12042167B2 (en) 2016-04-11 2024-07-23 RELIGN Corporation Arthroscopic devices and methods
US10595889B2 (en) 2016-04-11 2020-03-24 RELIGN Corporation Arthroscopic devices and methods
US11426231B2 (en) 2017-01-11 2022-08-30 RELIGN Corporation Arthroscopic devices and methods
US12004765B2 (en) 2017-03-17 2024-06-11 RELIGN Corporation Arthroscopic devices and methods
US11065023B2 (en) 2017-03-17 2021-07-20 RELIGN Corporation Arthroscopic devices and methods

Also Published As

Publication number Publication date
GB735549A (en) 1955-08-24
CH313048A (fr) 1956-03-15
ES210942A1 (es) 1953-12-16
NL181352B (nl)
DE1017695B (de) 1957-10-17
FR1086464A (fr) 1955-02-14
NL90626C (enrdf_load_stackoverflow)

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