Coil Patents (Class 218/129)
  • Patent number: 11811213
    Abstract: A transformer assembly including a transformer that is part of an underground residential power distribution circuit and that provides fault isolation and restoration. The transformer assembly includes an enclosure enclosing a primary winding and a secondary winding. The transformer assembly also includes first and second switching devices mounted to a panel of the enclosure, where each switching device includes an outer housing, a transformer interface electrically coupled to the primary winding, a connector interface electrically coupled to a first connector and a vacuum interrupter having a fixed contact and a movable contact. The fixed contact is electrically coupled to the connector interface or the transformer interface and the movable terminal is electrically coupled to the other connector interface or the transformer interface.
    Type: Grant
    Filed: August 12, 2021
    Date of Patent: November 7, 2023
    Assignee: S&C Electric Company
    Inventors: Nicholas Seng, Michael R Maroney, Alejandro Montenegro, Goran Djogo
  • Patent number: 11676778
    Abstract: A system for isolating a fault in a direct current (DC) grid using thermionic arc extinction. The system includes a DC grid that includes a transmission line. The DC grid also includes a plurality of current interrupters disposed on the transmission line. Each of the plurality of current interrupters on the transmission line are electrically coupled to one another in series. At least one of the current interrupters includes a fixed terminal end and a moveable terminal end. Further, at least one of the current interrupters has an arc shield housing at least two arcing contacts. At least one of the arcing contacts comprises a first conducting material that has a first vaporizing point.
    Type: Grant
    Filed: November 11, 2021
    Date of Patent: June 13, 2023
    Assignee: Stacom Engineering Company
    Inventor: Frank P Stacom
  • Patent number: 10643808
    Abstract: A vacuum switching device may have at least one cup-shaped contact closed by a disc of contact material and a conical mechanical support, which acts to prevent the contact disc from becoming concave. The cup-shaped contact may include a plurality of slots in the sidewalk that extend into the base of the cup, the slots oriented to produce an axial magnetic field when current flows through the contacts. The support may be made of a metal that is a poor conductor of electricity. The narrow end of the cone may be capped by a circular ring or disc, and the wide end may be formed with a flange. The flange may be circular and may be sized and formed to locate the cone centrally in the base of the contact cup. The cone may have apertures to facilitate the evacuation of gas inside the cone.
    Type: Grant
    Filed: October 9, 2018
    Date of Patent: May 5, 2020
    Assignee: S&C Electric Company
    Inventor: Leslie Thomas Falkingham
  • Patent number: 10410813
    Abstract: An electrical contact is for a vacuum switching apparatus. The electrical contact includes a hub portion and a plurality of petal portions extending radially outwardly from the hub portion. The electrical contact is made from conductive materials and insulating materials.
    Type: Grant
    Filed: April 3, 2018
    Date of Patent: September 10, 2019
    Assignee: EATON INTELLIGENT POWER LIMITED
    Inventors: Koustubh Dnyandeo Ashtekar, Steven Z. Chen, Geraldo Nojima, Robert Patton Griffin
  • Patent number: 10128070
    Abstract: The invention provides a contact for a high-voltage vacuum arc extinguishing chamber. The contact of the invention includes a conductive connecting piece, an annular outer contact and an inner contact which is located within the ring of the outer contact and does not contact with the outer contact. The conductive connecting piece, inner contact and outer contact are coaxial and the contact surface of the inner contact is on the same plane as that of the outer contact. The outer contact is fixed on the conductive connecting piece. An axial magnetic field means is covered outside of the conductive connecting piece for generating an axial magnetic field. The axial magnetic field means is fixedly connected with the conductive connecting piece. The inner contact is fixed on the conductive connecting piece. A circumferential magnetic field means is covered outside of the conductive connecting piece for generating a circumferential magnetic field.
    Type: Grant
    Filed: March 18, 2014
    Date of Patent: November 13, 2018
    Assignee: Zhejiang Ziguang Electric Appliance Co., Ltd.
    Inventors: Heming Zhou, Zhiyuan Liu, Haiyong Lin
  • Patent number: 9640353
    Abstract: A contact assembly for use in a vacuum interrupter includes a contact disc of a first electrically conductive material, a coil, and a contact support. The coil is made from a second electrically conductive material and includes multiple helical sections that are oriented axially with respect to a common central axis. Each of the helical sections includes a proximal end and a distal end such that each of the helical sections is connected at the proximal end to a base made from the second electrically conductive material and is connected at the distal end to the contact disc. The contact support is centered axially within the coil and extends from the base to the contact disc.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: May 2, 2017
    Assignee: Thomas & Betts International LLC
    Inventor: Bryce Franklin Sollazzi
  • Patent number: 9330869
    Abstract: A coil electrode has a ring section provided on a plane perpendicular to the axis line of fixed-side and movable-side electrode rods on which the coil electrodes are mounted and concentrically with the axis line, a plurality of arm sections extended outward from the outer circumference of the ring section, circular-arc-shaped coil sections that are formed in such a way as to be bent in the circumferential direction from the respective front ends of the arm sections, and slits that separate the coil sections; the arm section of the coil electrode and the arm section of the coil electrode are arranged in the same direction so as to be superimposed on each other when viewed along the axis direction of the fixe-side electrode rod and the movable-side electrode rod.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: May 3, 2016
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Takakazu Harada
  • Patent number: 9040862
    Abstract: An electrode assembly for a vacuum interrupter is configured such that supporting members can support most of a contact electrode plate and a supporting electrode plate in an axial direction with coil conductors interposed therebetween. Accordingly, an impact generated between electrode assemblies upon a closing operation of the vacuum interrupter may be evenly distributed onto the supporting members, which may result in preventing each of the electrode plates and the coil conductors from being deformed. Also, the supporting members are inserted into the electrode plates and the coil conductors, thereby effectively preventing a current from flowing via the supporting members. In addition, the supporting member may be wide and large so as to simplify an assembly operation and reduce an assembly time.
    Type: Grant
    Filed: June 19, 2012
    Date of Patent: May 26, 2015
    Assignee: LSIS Co., Ltd.
    Inventor: Jae Seop Ryu
  • Patent number: 8835790
    Abstract: A design for a winding is based on a material of low electrical resistance, such as copper, and of a diameter typically greater than 90 mm, intended to generate a magnetic field in an electrical contact for a medium voltage vacuum circuit-breaker. The winding includes a hollow cylinder including helical slots that are empty of material, arranged in parallel around its longitudinal axis, and that open out both to the hollow and to the outside of the cylinder. The angular length of each helical slot is equal to at least 360°. The design makes it possible to increase the level of the axial magnetic field (AMF) obtained by the winding(s) incorporated into an electrical contact of a vacuum circuit-breaker while improving uniformity, symmetry of the field, and production cost.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: September 16, 2014
    Assignee: Schneider Electric Energy France
    Inventor: Said Kantas
  • Patent number: 8450630
    Abstract: Exemplary contact backings for vacuum interrupters are described.
    Type: Grant
    Filed: July 30, 2007
    Date of Patent: May 28, 2013
    Assignee: Cooper Technologies Company
    Inventor: Paul N. Stoving
  • Patent number: 8350175
    Abstract: A device for diverting energy away from an arc flash occurring within an electrical power system is provided. The device comprising an arc source configured to create a second arc flash, a plasma gun configured and disposed to inject plasma in proximity of said arc source in response to the arc flash, an arc containment device configured and disposed to house said arc source and said plasma gun, said arc containment device comprising a cover configured and disposed to cover said arc source and said plasma gun, said cover comprising an inner surface and an outer surface, said inner surface being proximal to said arc source and said plasma gun, said inner surface including an insulative ceramic plasma spray coating.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: January 8, 2013
    Assignee: General Electric Company
    Inventors: Daniel Edward Delfino, David Vincent Bucci, Aaron Engel, William Ladner
  • Patent number: 8274007
    Abstract: A magnetic interrupter consisting of a stationary and moving butt contacts that open an electric circuit in dielectric gas (e.g., SF6) contained in a sealed, pressurized insulating housing. One or both of the contacts contain a magnet with poles spaced apart in a radial plane perpendicular to the axial direction to spin the arc in the radial plane about the center of the contacts. Permanent magnets may be used to spin the arc so that the magnetic field is not affected by the magnitude of the arcing current, which makes the magnetic interrupter suitable for interrupting currents below fault level currents. One or both of the magnets may also be a field coil and a permanent magnet may be used in combination with a field coil.
    Type: Grant
    Filed: August 19, 2010
    Date of Patent: September 25, 2012
    Inventors: Frank Clay Blalock, Joseph R. Rostron, Jeremy Andrew Stone
  • Patent number: 8269586
    Abstract: A large-capacity vacuum circuit breaker that can increase a current shutdown capacity and enables its rated current to be increased includes at least two vacuum circuit breaker units placed side by side and connected in parallel. The two vacuum circuit breaker units are operated by a single common operating unit to concurrently perform current shutdown operations. Each vacuum circuit breaker unit has a vertical magnetic field generating means for generating a vertical magnetic field when an operation to shut down current is performed. The vertical magnetic field generating means is formed by vertical magnetic field electrodes provided in a vacuum container of each of the vacuum circuit breaker unit units or by an external coil provided on the outer circumference of each vacuum container.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: September 18, 2012
    Assignee: Japan AE Power Systems Corporation
    Inventors: Yoshihiko Matsui, Mitsuyasu Shiozaki
  • Patent number: 8263894
    Abstract: Disclosed is an electrode for a vacuum interrupter, capable of reducing damage of contacts due to heat concentration to the center of the contacts, by reducing magnetic flux concentration to the center of the electrode, and capable of rapidly extinguishing an arc by diffusing the arc by forming a wide range of magnetic flux.
    Type: Grant
    Filed: January 4, 2010
    Date of Patent: September 11, 2012
    Assignee: LS Industrial Systems Co., Ltd.
    Inventors: Sung Jun Tak, Jae Seop Ryu
  • Patent number: 8168910
    Abstract: A vacuum circuit-breaker wherein at least in one of the contacts at least one stud is used as a spacer, and is disposed between the mechanical connection portion and the circular plate of the contact body in such a manner as to avoid the collapse thereof during a closing operation of the vacuum circuit-breaker, and in the closed position the contacts can withstand very high compression forces, typically greater than 700 kg-force or 2 t-force.
    Type: Grant
    Filed: June 2, 2010
    Date of Patent: May 1, 2012
    Assignee: Areva T&D SAS
    Inventors: Martin Schlaug, Uwe Ernst, Saïd Kantas, Xavier Godechot, Laëtita Dalmazio, Pierre Newinger
  • Patent number: 8164019
    Abstract: A vacuum circuit-breaker wherein one contact body is made with two windings implanted concentric with one another and connected electrically in parallel. The second winding is in the form of an solid part with an annular ring. The circuit-breaker increases the axial magnetic field (AMF) and distributes it uniformly over the contact surface so that arc extinction is improved for high short-circuit currents, typically greater than 63 kA.
    Type: Grant
    Filed: June 2, 2010
    Date of Patent: April 24, 2012
    Assignee: Areva T&D SAS
    Inventors: Martin Schlaug, Uwe Ernst, Saïd Kantas, Xavier Godechot, Laëtita Dalmazio, Rama Shanker Parashar
  • Patent number: 7721428
    Abstract: An electrode assembly for use in a vacuum interrupter is made by joining a first side of a substantially disk-shaped structure to an end of a substantially cylindrical coil segment, and joining an electrical contact to a second side of the disk-shaped structure. The disk-shaped structure has a higher resistivity than a resistivity of the coil segment.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: May 25, 2010
    Assignee: Cooper Technologies Company
    Inventors: Paul N. Stoving, E. Fred Bestel
  • Publication number: 20080302764
    Abstract: Exemplary contact backings for vacuum interrupters are described.
    Type: Application
    Filed: July 30, 2007
    Publication date: December 11, 2008
    Applicant: Cooper Technologies Company
    Inventor: Paul N. Stoving
  • Patent number: 6870118
    Abstract: A contact for a vacuum interrupter, includes: 1) a contact plate; and 2) a contact carrier. The contact carrier includes: a first end face which is fitted with the contact plate, and a peripheral face which is formed with a slit portion in such a manner as to form a coil part. The coil part flows a current such that a longitudinal magnetic field is formed in an axial direction of the contact carrier. The first end face fitted with the contact plate is formed with a circumferential slit portion which connects to the slit portion.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: March 22, 2005
    Assignee: Kabushiki Kaisha Meidensha
    Inventors: Akira Nishijima, Hidemitsu Takebuchi, Yoshihiko Matsui, Takaaki Furuhata
  • Patent number: 6762388
    Abstract: The present invention relates to a vacuum cartridge for an electrical protection apparatus such as a switch or a circuit breaker, said cartridge comprising an enclosure of substantially cylindrical shape closed by two end plates, two contacts extending axially inside the enclosure, at least one whereof, called the movable contact, is connected to an operating mechanism and is mounted sliding between a closed position of the contacts enabling the current to flow and a position wherein the contacts are separated and form an electric arc between them, and a means for producing an axial magnetic field in the arc formation zone. This cartridge comprises at least one conducting shield fitted around the periphery of at least one of the contacts, said shield being shaped and arranged in such a way as to withstand the electric field arising from the recovery voltage imposed by the power system after breaking and to thus considerably reduce the electric field at the edge of said contact.
    Type: Grant
    Filed: June 10, 2003
    Date of Patent: July 13, 2004
    Assignee: Schneider Electric Industries SAS
    Inventors: Hans Schellekens, Serge Olive
  • Patent number: 6686552
    Abstract: A contact for a vacuum interrupter, includes: 1) a contact plate; and 2) a contact carrier. The contact carrier includes: a first end face which is fitted with the contact plate, and a peripheral face which is formed with a slit portion in such a manner as to form a coil part. The coil part flows a current such that a longitudinal magnetic field is formed in an axial direction of the contact carrier. The first end face fitted with the contact plate is formed with a circumferential slit portion which connects to the slit portion.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: February 3, 2004
    Assignee: Kabushiki Kaisha Meidensha
    Inventors: Akira Nishijima, Hidemitsu Takebuchi, Yoshihiko Matsui, Takaaki Furuhata
  • Patent number: 6649855
    Abstract: In a contact arrangement and a vacuum interrupter using the contact arrangement, the contact arrangement includes: a hollow cylindrical contact carrier on one end surface of which a contact plate is attached; a plurality of first slits formed on the contact carrier from the one end surface of the contact carrier; and a plurality of second slits formed on the contact carrier from each predetermined point of midway through an axial direction of the contact carrier, each of the first and second slits being tilted with respect to the axial direction of the contact carrier, a coil portion being formed on a portion of the hollow cylindrical contact carrier between each of the first and second slits and an adjacent one of the first and second slits and a longitudinal magnetic field being formed along the axial direction of the contact carrier by a current flowing on the coil portion.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: November 18, 2003
    Assignee: Kabushiki Kaisha Meidensha
    Inventors: Akira Nishijima, Hidemitsu Takebuchi, Yoshihiko Matsui
  • Patent number: 5804788
    Abstract: A vacuum interrupter includes a pair of separable electrode assemblies within a vacuum envelope, each electrode assembly including a contact confronting the contact of the other electrode assembly and an electrode coil assembly located behind the contact for generating a magnetic field in a region between the contacts. The electrode coil assembly, which is energized by an a.c. current in the interrupter, includes a generally annular-shaped member having a plurality of slots extending radially between a peripheral surface and an interior surface, the slots defining a substantially circumferential current path. The slots include an axially extending slot and a circumferentially extending slot that define a coil. The electrode coil member is connected in series between a terminal post and the contact of the electrode assembly. The electrode coil assembly also can include a tubular support for the contact.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: September 8, 1998
    Assignee: Eaton Corporation
    Inventor: Robert Kirkland Smith
  • Patent number: 5793008
    Abstract: A vacuum circuit interrupter has a coil for generating an axially oriented magnetic field to maintain an electric arc in a diffuse rather than columnar mode upon opening of the interrupter. At least one of two electrodes having abuttable disc shaped contacts is movable along an axis relative to the other and can be forced by an external mechanism to open. The electrodes are carried in a housing with an electrical insulator between opposite end mountings that support the electrodes with the contacts in an evacuated enclosure. One of the electrodes is an assembly including a rigid supporting member attached to one of the contacts and extending a length along the axis. A coil is wrapped circumferentially around the supporting member along this length, providing a conductive path to generate the axial magnetic field. The supporting member comprises a less-conductive path (e.g., a stainless steel sleeve) and the coil is more conductive (e.g., copper), providing a durable and inexpensive structure.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: August 11, 1998
    Assignee: Eaton Corporation
    Inventors: Stephen David Mayo, Paul Graham Slade, Michael Bruce Schulman
  • Patent number: 5777287
    Abstract: An electrode assembly for a vacuum interrupter is disclosed having a coil structure that produces an axial magnetic field during operation of the assembly. The electrode coil includes at least one arcuate arm having a radial cross section which provides more material adjacent to a base of the coil than adjacent to a contact plate of the assembly. In a preferred embodiment, the cross sectional area of the arcuate arm has a trapezoidal shape. The electrode assembly provides improved heat transfer during operation of the vacuum interrupter while maintaining a sufficient axial magnetic field. As a result, the electrode assembly may be operated at higher continuous currents than conventional designs.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: July 7, 1998
    Assignee: Eaton Corporation
    Inventor: Stephen D. Mayo
  • Patent number: 5726406
    Abstract: An elongated vacuum cartridge having a cylindrical enclosure blanked off by two end-plates and housing a stationary arcing contact securedly united to one of the end-plates and a movable arcing contact mounted axially and slidingly inside the cartridge thereby providing a closed position and a separated position of the arcing contacts. An axial magnetic field in the arc formation zone is provided by a horizontal component of arcing current having an inclined trajectory with resect to the plane of the contact surfaces of the arcing contacts, the inclined trajectory being provided by angularly offset and alternating conductive and non-conductive sectors on the ends of each of the arcing contacts.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: March 10, 1998
    Assignee: Schneider Electric SA
    Inventors: Roger Bolongeat-Mobleu, Hans Schellekens
  • Patent number: 5697150
    Abstract: According to the present invention there are provided a highly reliable electrode of high strength which undergoes little change even with the lapse of time, and a method for making the same, as well as a vacuum valve using such electrode and a vacuum circuit breaker using such vacuum valve. The vacuum circuit breaker has a fixed electrode and a movable electrode, each comprising an arc electrode, an arc electrode support member for supporting the arc electrode, and a coil electrode contiguous to the arc electrode support member, the arc electrode, the arc electrode support member and the coil electrode being formed as an integral structure by melting, not by bonding, particularly the arc electrode support member and the coil electrode being constituted by a Cu alloy containing 0.05-2.5% by weight of at least one of Cr, Ag, W, V and Zr.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: December 16, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiro Komuro, Yoshitaka Kojima, Yukio Kurosawa, Yoshio Koguchi, Toru Tanimizu, Yoshimi Hakamata, Shunkichi Endo
  • Patent number: 5691522
    Abstract: An axial magnetic field vacuum interrupter includes a field producing structure associated with only one of two opposing electrode assemblies. The field producing structure is characterized in that when the instantaneous peak arc current is I.sub.m, measured in kiloamperes, and the electrode assemblies are in the open circuit position, the instantaneous component of the axial magnetic filed (AMF) B in the axial direction B.sub.a, measured in milliteslas, imposed on the majority of each electrode contact surface is given by the analytical expression.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 25, 1997
    Assignee: Eaton Corporation
    Inventors: Michael Bruce Schulman, Paul G. Slade
  • Patent number: 5691521
    Abstract: A vacuum switch having a fixed side electrode unit and a movable side electrode unit mounted in a vacuum vessel. Each electrode unit includes an arc electrode, an arc electrode supporting member for supporting the arc electrode, a coil electrode and a conducting rod. Joining portions between the arc electrode and the arc electrode supporting member, the coil electrode and the conducting rod are integrally and directly formed metallurgically by solid phase diffusion using a hot isostatic process. A vacuum circuit breaker may be constructed incorporating the vacuum switch.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: November 25, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiro Komuro, Yoshitaka Kojima, Yukio Kurosawa, Shunkichi Endoo, Tooru Tanimizu, Yoshimi Hakamata, Katsumi Kuroda
  • Patent number: 5646386
    Abstract: In a vacuum interrupter comprising a disc-shaped stationary electrode and a disc-shaped movable electrode arranged in an evacuated envelope in opposed relationship. A main electrode is in electrical contact with a coil electrode having arm parts and coil parts to establish predetermined current flows when the stationary and movable electrodes separate.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: July 8, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsumasa Yorita, Hideaki Toya, Hiroshi Hasegawa, Kenichi Koyama
  • Patent number: 5612523
    Abstract: A portion of a highly conductive metal member is infiltrated in voids of a porous high melting point metal member, and both the metal members are integrally joined to each other. An arc electrode portion 13 is formed of a high melting point area 11 in which the highly conductive metal is infiltrated in voids of the high melting point metal member. A coil electrode portion 14 is formed by hollowing out the interior of a highly conductive metal area 12 composed only of highly conductive metal and by forming slits 15 to 17 thereon. A rod 18 is hard-brazed on the rear surface of the coil electrode portion 14. With this electrode, it is possible to reduce the number of parts, and to omit the brazing portion between the arc electrode portion 13 and the coil electrode portion 14 for lowering the electric resistance and thereby the calorific value.
    Type: Grant
    Filed: March 7, 1994
    Date of Patent: March 18, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Yoshimi Hakamata, Toru Tanimizu, Akira Osaka, Katsuhiro Komuro
  • Patent number: 5597993
    Abstract: A vacuum interrupter comprising each electrode assembly of a pair of electrode assemblies having substantially the same structure and arranged in an evacuated envelope in opposed relationship adapted to be connected with or disconnected from each other. Each electrode assembly includes a coil electrode having a plurality of arms extending outwardly from a center ring shaped holding part and a plurality of arc-shaped coil parts formed substantially along the same circumference of the coil electrode and connected to respective ones of the arms, a main electrode including an arc-shaped arm electrically connected to each arc-shaped coil part of the coil electrode, the coil parts being in contact with corresponding ones of the arc-shaped arms along entire surfaces thereof, and a first arm connected to each of the arc-shaped arms of the main electrode and extended substantially toward a center of the main electrode in the radial direction.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 28, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsumasa Yorita, Hideaki Toya, Hiroshi Hasegawa, Kenichi Koyama
  • Patent number: 5557083
    Abstract: According to the present invention there are provided a highly reliable electrode of high strength which undergoes little change even with the lapse of time, and a method for making the same, as well as a vacuum valve using such electrode and a vacuum circuit breaker using such vacuum valve. The vacuum circuit breaker has a fixed electrode and a movable electrode, each comprising an arc electrode, an arc electrode support member for supporting the arc electrode, and a coil electrode contiguous to the arc electrode support member, the arc electrode, the arc electrode support member and the coil electrode being formed as an integral structure by melting, not by bonding, particularly the arc electrode support member and the coil electrode being constituted by a Cu alloy containing 0.05-2.5% by weight of at least one of Cr, Ag, W, V and Zr.
    Type: Grant
    Filed: June 27, 1994
    Date of Patent: September 17, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiro Komuro, Yoshitaka Kojima, Yukio Kurosawa, Yoshio Koguchi, Toru Tanimizu, Yoshimi Hakamata, Shunkichi Endo
  • Patent number: 5495085
    Abstract: In a vacuum interrupter comprising a disc-shaped stationary electrode and a disc-shaped movable electrode arranged in an evacuated envelope in opposed relationship, a slot or a salient part is formed on the surface of both the electrodes and thereby a path of an arc current in disconnection operation of both the electrodes is formed along the circumference of the disc-shaped electrode. The shape and position of the slot is selected so that the arc current flows uniformly along the entire circumference of both the electrodes.
    Type: Grant
    Filed: November 4, 1993
    Date of Patent: February 27, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsumasa Yorita, Hideaki Toya, Hiroshi Hasegawa, Kenichi Koyama