Abstract: A circuit breaker having a thermal tripping device comprising a bimetal element and a heater has a holding member attached to the stationary part of the bimetal element, for holding the bimetal element and the heater at respective first end parts thereof. The holding member has an arm connected to a flexible copper wire and generates heat when an over-current flows through it, the arm conducting this heat to the attached end part of the bimetal element to cause the bimetal element to bend and deflect a second end thereof to provide circuit breaking action.

Abstract: The present invention relates to a circuit breaker comprising at least a pair of electrical contactors formed of conductors and contacts secured to the conductors for opening or closing an electric circuit in a container, light absorbers having opposed surfaces disposed oppositely to each other from both sides of an arc produced between the contacts at the isolating time, a thermal absorber disposed oppositely to the openings of the opposed surfaces of the light absorbers except the moving trace portion of the electrical contactors, the light absorbers being formed of a composite material having one or more of fiber, net and porous material having more than 35% of apparent porosity selected from composite materials having inorganic series, organic series and composites of the inorganic series and the organic series, and the thermal absorber being formed of a composite material having one or more of an assembly of fine metal wires, porous metals, and a metal plate having a number of pores.

Abstract: A circuit interrupter which comprises, in a compartment defined in an electrically insulating housing, a pair of separable contacts defining, when separated, an arcing region therebetween, and an operating mechanism, including a tripping unit and an operating handle, for opening and closing the separable contacts. The housing which includes an electrically insulating bottom wall has a gas exhaust passage having an inlet opening in the inner surface of the housing. The inlet of the gas exhaust passage is located in the bottom wall at a position effective for exhausting an arced gas generated in the arcing region without contacting the operating mechanism.

Abstract: The present invention relates to a circuit breaker with an arc light absorber comprising: a pair of electric contactors contained in an insulating container for opening or closing an electric circuit, electric conductors forming said electric contactors and contacts provided at said conductors, an arc extinguishing plate for extinguishing an arc produced between said contacts when said electric contactors are opened, and a pair of side walls confronting the portion except the locuses drawn by said contacts when said contactors are opened and closed at the position of the arc extinguishing plate side of said locuses to form an arc light absorber, said side walls formed of a composite material having one or more of fiber, net or porous material having more than 35% of porosity and the arc produced between said contacts being discharged through between said pair of confronting side walls.

Abstract: The present invention relates to a circuit breaker with an arc light absorber comprising: a pair of contactors contained in an insulating container for opening or closing an electric circuit, electric conductors forming said electric contactors and contacts and arc runners provided at said conductors, and arc light absorbing side walls provided at both sides of said arc runners for absorbing the arc light energy irradiated directly to the arc produced between said contactors, said side walls being formed of a composite material having one or more of fiber, net or porous material having more than 35% of apparent porosity.

Abstract: A circuit breaker with an arc light absorber comprising: a pair of electric contactors contained in an insulating container for opening or closing an electric circuit, and having electric conductors and contacts provided on said conductors, and a pair of side walls on both sides of said contactors at positions for covering all the locuses of said contacts when said contactors are opened or closed, said side walls being formed of a composite material having one or more of fiber, net or porous material having more than 35% apparent porosity.

Abstract: The present invention consists in a circuit breaker wherein a pair of rigid conductors which are disposed therein and at least one of which has a movable portion that separates a pair of contacts on the basis of the electromagnetic force of an excess current flowing through the contacts adapted to come into and out of contact with and from each other, are provided with arc shields in a manner to surround the contacts, thereby to bring forth the effects of increasing the arc voltage of an electric arc struck across the contacts and raising the separating speed of the contacts.

Abstract: A circuit breaker in which arc shielding members are provided for predetermined contacts among a plurality of contact pairs arrayed in parallel, so that the arc will take place between predetermined contacts when the contacts are opened. The arc shielding members are made of a material having resistivity greater than that of the conductors to which the contacts are attached. The arc shielding members work to effectively inject metallic particles of contact material into the arc, so that the arcing voltage is rapidly raised and so that feet of the arc will not spread to the conductors in the vicinities of the contacts.

Abstract: A circuit breaker having means for quickly opening a pair of contacts, a U-shaped flux board which surrounds the conductors that have contacts attached to the end portions thereof, so that the electromagnetic repulsive force produced by the electric current that flows through the opposing conductors in opposite directions relative to each other, will be added to the operation of the contact-opening means. The circuit breaker of the invention is further equipped with arc shielding members surrounding the contacts, so that the arc established across the contacts will not stretch to the conductors in the vicinities of the contacts, and so that the arcing voltage is greatly increased.

Abstract: The present invention relates to a circuit breaker comprising a pair of contactors each comprising a rigid conductor with a contact secured thereon, wherein at least one of the contactors is also provided with an electrically conductive projection secured on the rigid conductor in proximity to the contact, the contact and the projection having their peripheries surrounded by a high resistivity arc shield of a resistivity higher than the rigid conductors. An arc extinguishing plate assembly is also provided to cool and extinguish an arc drawn across the gap between the contacts. With this arrangement, the arc is confined and has its voltage raised by the effects of the arc shield, and the size of the foot of the arc is limited such that it does not spread to the surface of the conductor in the vicinity of the contact.

Abstract: The present invention combines the provision of arc shields surrounding the contacts of a circuit breaker with a magnetic driving means to raise the arc voltage of an arc drawn across the contacts and to effectively drive the arc, whereby the performance of the circuit breaker is improved.

Abstract: The present invention provides a circuit breaker of improved performance by providing arc shields and arc runways together with the contacts on the rigid conductors of the contactors of a circuit breaker, and disposing said arc runways on the stationary contactor side is a predetermined relationship to the arc extinguishing plates such that a portion of the cut-out in at least one of said arc extinguishing plates substantially overlaps said arc runway.

Abstract: This invention provides a novel circuit breaker which is good in terms of both its current-limiting performance and its interrupting performance. The contactors of the circuit breaker for opening and closing an electric circuit are equipped with are shields of a high resistivity material, disposed in a manner to surround the contacts thereof, and arc runways of higher conductivity than the arc shields, and of predetermined heights and directions, are further provided in a manner so as to adjoin to the contacts.

Abstract: This invention provides a novel circuit breaker which is good in terms of both its current-limiting performance and its interrupting performance. The contactors of the circuit breaker for opening and closing an electric circuit are provided with arc shields of a high resistivity material, disposed in a manner to surround the contacts thereof, and arc runways of higher conductivity than the arc shields, and of predetermined dimensions and directions are further provided adjacent to the contacts.