US3005073A - High speed circuit breaker - Google Patents
High speed circuit breaker Download PDFInfo
- Publication number
- US3005073A US3005073A US829358A US82935859A US3005073A US 3005073 A US3005073 A US 3005073A US 829358 A US829358 A US 829358A US 82935859 A US82935859 A US 82935859A US 3005073 A US3005073 A US 3005073A
- Authority
- US
- United States
- Prior art keywords
- contact
- contacts
- circuit
- breaker
- spring
- 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
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H77/00—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting
- H01H77/02—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting in which the excess current itself provides the energy for opening the contacts, and having a separate reset mechanism
- H01H77/10—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting in which the excess current itself provides the energy for opening the contacts, and having a separate reset mechanism with electrodynamic opening
- H01H77/102—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting in which the excess current itself provides the energy for opening the contacts, and having a separate reset mechanism with electrodynamic opening characterised by special mounting of contact arm, allowing blow-off movement
- H01H77/104—Protective overload circuit-breaking switches operated by excess current and requiring separate action for resetting in which the excess current itself provides the energy for opening the contacts, and having a separate reset mechanism with electrodynamic opening characterised by special mounting of contact arm, allowing blow-off movement with a stable blow-off position
Definitions
- the present invention relates to circuit-breakers. More in particular, the present invention relates to highspeed automatic circuit-breakers particularly adapted for high voltages which are electro-magnetically or thermally operated, and more particularly still to circuit-breakers of the type referred to, wherein the contacts of the circuit-breaker are kept in closed position under normal operating conditions against the electro-dynamic force of the current passing through the switch.
- Circuit-breakers of the aforementioned type are subject to considerable thermic andv dynamic stress whenever there arise high overload currents, as, for example, in case of a short circuit.
- the greatest strain occurs at the respective peak value of alternating current.
- This strain is particularly great where the time for response of the circuit-breakers is comparatively long and the contacts need a predetermined period of time after the overload current has set in, to separate and to break the current circuit. It is, therefore, very important that the time elapsing between the first circuit-breaking impulse and the actual separation of the contacts of the circuit-breaker is reduced to a minimum.
- a further reduction of this lapse of tirne is, however, limited by the construction of the circuit-breaker mechanism and its inertia.
- circuit-breaker wherein the contacts perform a two-stage separating movement, the first stage comprising a comparatively small displacement just sufficient to bodily separate the contacts, and the second stage comprising a greater displacement sufficient for extinguishing the electric are between the contacts, thus separating the latter electrically.
- the circuit-breakers of this type are however extremely com- 3,005,071; Patented Oct.
- circuit-breaker particularly adapted for high curtents of the type wherein contact is normally maintained against the influence of the electro-dynamic force produced by the current fiow through the switch, which comprises means capable of accomplishing the aforementioned objectives, which actuate the contacts much faster than, and entirely independent from, the circuit-breaking action of the electro-magnetically 0r thermally operated contact actuating mechanisms known per se.
- circuit-breaker of the present invention which is of the type comprising a pair of relatively moveable contacts, and an electro-magnetically or thermally operated contact actuating mechanism.
- the circuitbreaker has an energy storing member tending to keep the,
- FIGURE 1 is a partial, side elevational view of the circuit-breaker of the invention with the contacts in closed position;
- FIGURE 2 is a partial, side clevational' view of the circuit-breaker 0f the invention with the contacts in opened position, the conventional contact-actuating mechanism still being in closed position;
- FIGURE 2 is a partial, side elevational view of the circuit-breaker of the invention with the contacts in opened position, and the conventional contact-actuating meehanism'now also having been moved into opened position;
- t 7 FIGURE 4 is a top view of a preferred embodiment of the contact-breaker of the invention;
- FIGURE 5 is a partial, side elevational View of a modification of the contact-breaker of the present invention, with the contacts in opened position;
- FIGURE 6 is a partial, side elevational view of a modification of the contact-breaker of the present invention, with the contacts in opened position;
- the circuit-breaker of the invention comprises a pair of relatively moveable contacts, such as a fixed contact 1 with a contact point In, and a mo-veable contact '2 having a contact point 2a.
- the moveable contact 2 is hingedly mounted on a shaft 3 about which it is simultaneously fulcrumed.
- the circuit-breaker comprises a conventional contact actuating mechanism for mechanically opening and closing contacts 1 and 2 which is known per se and, therefore, not shown in the drawings.
- This mechanism may be electromagnetically and/or thermally tripped, in a manner known per se.
- the circuit-breaker of the present invention further comprises a spring, such as tension spring 4, connected with one of its ends to a pin 14 on the switch traverse plate 7 and with its other end to a pin bolt 6 connected with the moveable contact 2.
- the traverse plate 7 is provided with a longitudinal guide recess 9 receiving the pin bolt 6 which is adapted to slide therein. Accordingly, plate 7 with recess 9 is a guide member for pin bolt 6 permitting a limited pivot motion of moveable contact 2. It is thus possible to open the contacts by the conventional contact actuating mechanism via shaft 8 and traverse plate 7 actuating moveable contact 2. via one of the edges of guide recess 9 and pin bolt 6.
- circuit-breaker of the present invention there are provided, associated with contacts 21 and 22, not one but two tension springs 24 and 24a, as well as two switch traverse plates 27 and 27a bearing a pin bolt 26a to which there are attached the springs 24 and 24a with one of their respective ends, and a pin bolt 26 adapted to slide in a recess of the traverse plates, to which there are attached the other respective ends of the springs 24- and 24a.
- the traverse plates are mounted and fulcrumed about a shaft 28 connected with the conventional spring actuating mechanism, not shown.
- a pressure spring instead of a tension spring.
- 31 designates the fixed contact having a contact point 31a, 32 the moveable contact having a contact point 3112, the moveable contact 32 being hinged- 1y mounted on and fulcrunied about a pin bolt 33 attached to the switch traverse plate 37 which latter is hingedly mounted on shaft 38 connected with the conventional contact actuating mechanism, not shown.
- the pressure spring 33 is fixed with one of its ends to a pin 40 mounted on the traverse plate 37, and with its other end to the pin bolt 36 mounted at the lowermost end of moveable contact 32 and adapted to travel in the guide recess 39 of the switch traverse plate 37.
- the circuitbreaker shown in FIGURES 5 and 6 thus substantially corresponds to the device shown and described with reference to FIGURE 1, with the exception that in the last described device there is provided a pressure spring and, accordingly, the moveable contact is fulcrumed differently, i.e., in the device shown in FIGURES 1 to 3 the fulcrum is situated below the point of attachment of the spring to the moveable contact via the pin bolt 6, Whereas in the circuit-breaker shown in FEGURES 5 and 6 the moveable contact 32 is fulcrumed about the fixing point of pressure spring 34 to the contact via pin bolt 36.
- the contact members of the circuit-breaker are preferably composed of a material having a low welding capacity; this will prevent the welding-together of the contacts under the influence of the electro-dynamic force produced by a short-circuit, and the resulting decrease of the contact pressure.
- the circuit-breaker of the present invention operates in the following manner, as described with reference to mined overload current occurs, for example in case of a short-circuit, the current loop and the narrow current passage and the contact points la, 2a, produce an electrodynamic force, based on the well-known fact that the current loop tends to widen itself, which force tends to push the two contacts apart, i.e., the moveahle contact 2 away from fixed contact 1 so as to separate the contact points 1a, 2a.
- the moveable contact is thus displaced in the direction of arrow 5 moving about shaft 3 on the traverse plate 7 as a fulcrum.
- the moveable contact can also be opened independently by the conventional contact actuating mechanism via traverse plate '7 which then takes along mo-veable contact 2 via the lent-hand edge of recess 9.
- the moveable contact 2 can be moved away from contact 1, both by the switch traverse plate '7 as well as independently from the latter under the influence of a predetermined overload current passing through contacts 1 and 2.
- the latter opening operation initiated by the electro-mechanical force produced by the ove'load current passing through contacts 1 and 2 is enhanced and greatly speeded up by the toggle-like action or" spring 4.
- the circuibbreakcr of the present invention as heretotore described and shown in the drawings has great advantages over the art, ;as the contacts are separated by accepts two mutually entirely independent operations, namely the electro-magnetically or thermally operated contact-actuating mechanism, on the one hand, and the electrodynamic force produced by the current flow through the contactelements, in conjunction with the energy storing member as its force component is reversed, on the other hand.
- the latter switching operation becomes effective where the current increases by a predetermined rate and there occurs a certain minimum overload current, e.g. a short-circuit current.
- the first-mentioned, conventiona1 contact-opening operation becomes effective in the case of predetermined smaller overload currents and is entirely sulficient for that purpose.
- the circuit-breaker of the invention ensures an early and quick opening of the contacts and safely extinguishes the electric are between the contacts independently from the much slower, following action of the conventional contact-actuating mechanism.
- An automatic circuit-breaker comprising a fixed contact and a movable contact, a contact-actuating mechanism keeping said contacts in closed position under predetermined normal current conditions while allowing for the opening of said contacts under the influence of the electro-dynarnic force produced by a predetermined overload current, and additional contact-actuating means connected with said contact-actuating mechanism producing a force component tending to keep said contacts in their respective end positions, which force component is reversed whenever said predetermined overload current has thereby, a guide recess in said traverse, an unstable spring,
- a bolt connected with said movable contact and to one end of said unstable spring, said bolt being guided in said guide recess and having a first end position in which said contacts are closed and a second end position in which said contacts are opened, said bolt being movable from said first end position to said second end position and vice versa by said traverse and also independently from said traverse and said contacoactuating mechanism by the influence of the electro-dynamic force of a predetermincdoverload current passing through said contacts.
- An electric switching device comprising: a first stationary contact; a second movable contact for engaging said first contact, said contacts being subjected to electrodynamic repelling force when closed and conduct electric current; spring means biasing said second contact in a direction urging said second contact towards said first contact; and a movable guide member engaging said second contact for moving said spring and said second contact between a closed and an open position whereby the direction of the force of said spring means remains the same, said member permitting limited relative movement of said second contact under the influence of an excessive electrodynamic repelling force, so that the bias force exerted by said spring upon said second contact be reversed.
- An electric switching device comprising: a stationary contact; a pivotable contact capable of engaging said stationary contact, there being an electrodynamic force exerted upon said contacts when an electric current flows therethrough urging said contacts apart from each other; apivotally mounted switch traverse; a spring secured with one end to said traverse at location displaced from the pivot point thereof, and secured with the other end to said pivotable contact arm whereby the line between the connections of said spring is located on one side of the pivot point of said pivotable contact and a force component urges the latter towards the stationary contact when the contacts are closed, said line passing over said pivot point when said pivotable contact opens under excessive electrodynamic forces; and means for engaging said traverse and said pivotab'le contact for common pivot motion to a contact-open position whereby the side relationship of said line and said pivot point of said contact remain the same.
- An electric switching device comprising: a station ary contact; a pivotable contact capable of engaging said stationary contact, there being an electrodynamic force exerted upon said contacts when an electric current flows therethrough urging said contacts apart; a spring connected to and urging said pivotable contact towards said stationary contact in opposition to said force; a switch traverse supporting said pivotable contact and permitting relative movement in a limited range for opening and closing said contacts substantially independent from and without substantially altering the urging force exerted by said spring; and means for connecting said spring to said traverse at such a location, that excessive electrodynamic forces overcome said spring force and reverse its direction whereby the position of said traverse is unchanged.
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Breakers (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEL30935A DE1079176B (de) | 1958-07-30 | 1958-07-30 | Fuer vorzugsweise hoehere Stromstaerken geeigneter Selbstschalter mit elektromagnetischen und/oder thermischen Ausloesern |
Publications (1)
Publication Number | Publication Date |
---|---|
US3005073A true US3005073A (en) | 1961-10-17 |
Family
ID=7265385
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US829358A Expired - Lifetime US3005073A (en) | 1958-07-30 | 1959-07-24 | High speed circuit breaker |
Country Status (6)
Country | Link |
---|---|
US (1) | US3005073A (zh) |
CH (1) | CH377431A (zh) |
DE (1) | DE1079176B (zh) |
FR (1) | FR1232636A (zh) |
GB (1) | GB909165A (zh) |
NL (2) | NL241741A (zh) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3118032A (en) * | 1960-04-26 | 1964-01-14 | Gen Electric | Bypass disconnect type switch |
US3192344A (en) * | 1961-08-28 | 1965-06-29 | Fed Pacific Electric Co | High interrupting capacity circuit breakers with electrodynamic latch release |
US3215796A (en) * | 1960-12-19 | 1965-11-02 | Siemens Ag | Electrodynamic drive for synchronous circuit interrupters |
US3277407A (en) * | 1964-03-16 | 1966-10-04 | Terasaki Denki Sangyo Kk | Circuit interrupter |
US3315189A (en) * | 1965-09-30 | 1967-04-18 | Gen Electric | Circuit breaker assembly |
US3317866A (en) * | 1963-02-07 | 1967-05-02 | Terasaki Denki Sangyo Kk | Automatic circuit interrupter having magnetic blowoff means |
US3359485A (en) * | 1963-09-27 | 1967-12-19 | Bbc Brown Boveri & Cie | Tap changing device for transformer windings without interrupting the load current |
US4488133A (en) * | 1983-03-28 | 1984-12-11 | Siemens-Allis, Inc. | Contact assembly including spring loaded cam follower overcenter means |
US4550299A (en) * | 1983-07-04 | 1985-10-29 | Asea Aktiebolag | Electric switch with protective function |
US4855549A (en) * | 1986-07-24 | 1989-08-08 | Mitsubishi Denki Kabushiki Kaisha | Circuit breaker |
US5310971A (en) * | 1992-03-13 | 1994-05-10 | Merlin Gerin | Molded case circuit breaker with contact bridge slowed down at the end of repulsion travel |
DE29505890U1 (de) * | 1995-04-05 | 1995-06-01 | Heinrich Kopp Ag, 63796 Kahl | Kontaktanordnung |
US20090072933A1 (en) * | 2004-11-19 | 2009-03-19 | Abb Services S.R.I | Automatic circuit breaker with tripping device activated by a movable contact |
Families Citing this family (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1127452B (de) * | 1960-02-16 | 1962-04-12 | Elektro App Werke J W Stalin V | Elektrischer UEberstromselbstschalter |
DE1128009B (de) * | 1960-07-27 | 1962-04-19 | Licentia Gmbh | Gleichstromschnellschalter |
DE1125057B (de) * | 1960-08-19 | 1962-03-08 | Elektro App Werke J W Stalin V | Schnellschalter |
DE1282776B (de) * | 1960-09-08 | 1968-11-14 | Siemens Ag | Elektrischer Schalter |
DE1194956B (de) * | 1961-07-06 | 1965-06-16 | Licentia Gmbh | Elektromagnetisches Schaltschuetz |
DE1183584B (de) * | 1962-01-25 | 1964-12-17 | Siemens Ag | Einrichtung zur Kontakttrennung bei grossen UEberstroemen |
GB1052519A (zh) * | 1963-04-11 | 1900-01-01 | ||
DE1463311B2 (de) * | 1963-05-16 | 1970-03-19 | Licentia Gmbh | Selbstschalter mit strombegrenzender OEffnung des Kontaktsystems |
DE1663047B1 (de) * | 1964-03-04 | 1970-02-26 | Starkstrom Schaltgeraetefabrik | Ein- oder mehrpoliger Selbstschalter |
DE1293310B (de) * | 1965-07-28 | 1969-04-24 | Siemens Ag | Einrichtung zur unmittelbaren Kontaktoeffnung bei UEberstroemen |
JPS4838365U (zh) * | 1971-09-09 | 1973-05-11 | ||
US4259651A (en) * | 1978-10-16 | 1981-03-31 | Westinghouse Electric Corp. | Current limiting circuit interrupter with improved operating mechanism |
JPS56122246U (zh) * | 1980-02-19 | 1981-09-17 | ||
US4513267A (en) * | 1983-03-28 | 1985-04-23 | Siemens-Allis, Inc. | Stationary contact strap to achieve a current limiting blow-off effect |
DE3347120A1 (de) * | 1983-12-22 | 1985-07-11 | Siemens AG, 1000 Berlin und 8000 München | Elektro-dynamisch oeffnendes kontaktsystem |
US4680562A (en) * | 1985-07-29 | 1987-07-14 | Westinghouse Electric Corp. | Integral circuit interrupter with separable modules |
US4660009A (en) * | 1985-07-29 | 1987-04-21 | Westinghouse Electric Corp. | Modular integral circuit interrupter |
IT206253Z2 (it) * | 1985-10-18 | 1987-07-13 | Sace Spa | Interruttore elettrico limitatore di corrente ad apertura dei contatti per repulsione elettrodinamica. |
JPS6320342U (zh) * | 1986-07-24 | 1988-02-10 | ||
DE3708807A1 (de) * | 1987-03-18 | 1988-10-06 | Licentia Gmbh | Elektrischer leistungsschalter mit einem elektro-dynamisch oeffnenden kontaktsystem |
DE3736013A1 (de) * | 1987-10-23 | 1989-05-11 | Kloeckner Moeller Elektrizit | Kontaktsystem fuer einen leistungsschalter |
DE4222965C1 (de) * | 1992-07-13 | 1993-11-25 | Kloeckner Moeller Gmbh | Kontaktsystem für einen Schalter, insbesondere für einen Leistungs- bzw. Schutzschalter |
US5504291A (en) * | 1994-02-14 | 1996-04-02 | Square D Company | Contact blade assembly for a circuit breaker |
DE102005050705B4 (de) * | 2005-10-05 | 2008-07-31 | Moeller Gmbh | Kontaktsystem für einen Niederspannungsschalter |
FR2987162B1 (fr) * | 2012-02-16 | 2016-04-15 | Hager-Electro Sas | Contact mobile bistable |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1724840A (en) * | 1926-03-26 | 1929-08-13 | Gen Electric | Circuit maker and interrupter |
US2514839A (en) * | 1944-06-17 | 1950-07-11 | Ite Circuit Breaker Ltd | Broken back circuit breaker contact |
US2769049A (en) * | 1951-08-09 | 1956-10-30 | Ite Circuit Breaker Ltd | Quick-break circuit breaker |
US2800558A (en) * | 1956-05-07 | 1957-07-23 | Gen Electric | Electric circuit breaker |
US2839632A (en) * | 1954-11-18 | 1958-06-17 | Comp Generale Electricite | Circuit breaker |
US2840671A (en) * | 1954-08-30 | 1958-06-24 | Siemens Ag | Circuit interrupter |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH109564A (de) * | 1924-04-24 | 1925-04-01 | Oerlikon Maschf | Elektrischer Schnellschalter. |
US2037570A (en) * | 1935-02-01 | 1936-04-14 | Gen Electric | High speed circuit breaker |
CH235663A (de) * | 1943-07-09 | 1944-12-15 | Landis & Gyr Ag | Kontaktanordnung. |
GB580701A (en) * | 1944-07-18 | 1946-09-17 | William Sharp | Improvements in snap-action electric switches |
-
0
- NL NL112822D patent/NL112822C/xx active
- NL NL241741D patent/NL241741A/xx unknown
-
1958
- 1958-07-30 DE DEL30935A patent/DE1079176B/de active Pending
-
1959
- 1959-07-11 CH CH7570959A patent/CH377431A/de unknown
- 1959-07-24 US US829358A patent/US3005073A/en not_active Expired - Lifetime
- 1959-07-27 FR FR801246A patent/FR1232636A/fr not_active Expired
- 1959-07-29 GB GB26030/59A patent/GB909165A/en not_active Expired
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1724840A (en) * | 1926-03-26 | 1929-08-13 | Gen Electric | Circuit maker and interrupter |
US2514839A (en) * | 1944-06-17 | 1950-07-11 | Ite Circuit Breaker Ltd | Broken back circuit breaker contact |
US2769049A (en) * | 1951-08-09 | 1956-10-30 | Ite Circuit Breaker Ltd | Quick-break circuit breaker |
US2840671A (en) * | 1954-08-30 | 1958-06-24 | Siemens Ag | Circuit interrupter |
US2839632A (en) * | 1954-11-18 | 1958-06-17 | Comp Generale Electricite | Circuit breaker |
US2800558A (en) * | 1956-05-07 | 1957-07-23 | Gen Electric | Electric circuit breaker |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3118032A (en) * | 1960-04-26 | 1964-01-14 | Gen Electric | Bypass disconnect type switch |
US3215796A (en) * | 1960-12-19 | 1965-11-02 | Siemens Ag | Electrodynamic drive for synchronous circuit interrupters |
US3192344A (en) * | 1961-08-28 | 1965-06-29 | Fed Pacific Electric Co | High interrupting capacity circuit breakers with electrodynamic latch release |
US3317866A (en) * | 1963-02-07 | 1967-05-02 | Terasaki Denki Sangyo Kk | Automatic circuit interrupter having magnetic blowoff means |
US3359485A (en) * | 1963-09-27 | 1967-12-19 | Bbc Brown Boveri & Cie | Tap changing device for transformer windings without interrupting the load current |
US3277407A (en) * | 1964-03-16 | 1966-10-04 | Terasaki Denki Sangyo Kk | Circuit interrupter |
US3315189A (en) * | 1965-09-30 | 1967-04-18 | Gen Electric | Circuit breaker assembly |
US4488133A (en) * | 1983-03-28 | 1984-12-11 | Siemens-Allis, Inc. | Contact assembly including spring loaded cam follower overcenter means |
US4550299A (en) * | 1983-07-04 | 1985-10-29 | Asea Aktiebolag | Electric switch with protective function |
US4855549A (en) * | 1986-07-24 | 1989-08-08 | Mitsubishi Denki Kabushiki Kaisha | Circuit breaker |
US5310971A (en) * | 1992-03-13 | 1994-05-10 | Merlin Gerin | Molded case circuit breaker with contact bridge slowed down at the end of repulsion travel |
DE29505890U1 (de) * | 1995-04-05 | 1995-06-01 | Heinrich Kopp Ag, 63796 Kahl | Kontaktanordnung |
US20090072933A1 (en) * | 2004-11-19 | 2009-03-19 | Abb Services S.R.I | Automatic circuit breaker with tripping device activated by a movable contact |
US7750766B2 (en) * | 2004-11-19 | 2010-07-06 | Abb S.P.A. | Automatic circuit breaker with tripping device activated by a movable contact |
Also Published As
Publication number | Publication date |
---|---|
DE1079176B (de) | 1960-04-07 |
GB909165A (en) | 1962-10-24 |
NL112822C (zh) | |
CH377431A (de) | 1964-05-15 |
NL241741A (zh) | |
FR1232636A (fr) | 1960-10-11 |
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