Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Takao Mitsuhashi

Shinji Yamagata

Mitsugu Takahashi

Kazunori Fukuya

Kenichi Nishina

Hiroshi Adachi

Fumiaki Baba

Yoshiaki Kobayashi

Kazuharu Kato

Shunichi Katsube

Itsuo Nishiyama

Shoji Yamaguchi

Mitsuru Tsukima

Osamu Hiroi

Masahiro Fushimi

Tadaki Murakami

Mitugu Takahasi

Naoshi Yamada

Takashi Inaguchi

Shiro Murata

Satoru Yamasaki

Takeshi Ohi

Tosikazu Uemoto

Katsuhiko Fukuhara

Yoshitsugu Inaba

A semiconductor device accurately monitoring temperature of a semiconductor chip even in a noisy environment, while not requiring a highly accurate detection circuit. A PTC element is bonded onto an IGBT chip. Then, a constant current flows from a constant current source through the PTC element, and an output voltage of the PTC element is detected by a voltage monitor. When output voltage increases, a voltage applied to a gate electrode by a detection circuit is decreased. Since the PTC element is directly arranged on the IGBT chip, the temperature of the IGBT chip can be monitored with high accuracy. Further, since the change in output voltage of the PTC element per 1&#xb0; C. is large, a highly accurate detection circuit is not necessary, thereby allowing accurate monitoring of the temperature of the IGBT chip even in a noisy environment.

Semiconductor device

The circuit breaker includes a stationary contact member having a stationary contact, a movable contact member having at one end a movable contact contacting and separating from the stationary contact and having at the other end a rotational center, a case surrounding the stationary contact and the movable contact and defining a pressure accumulating space at one side of an arc generation position at which an electric arc is generated for temporarily storing a pressurized gas pressurized by the arc generated between the stationary and the movable contact upon a current interruption, and an exhaust port disposed at the other end of the arc generation position in the case so that the pressurized gas stored within the accumulation space upon the current interruption is exhausted by passing between the stationary contact and the movable contact.

Circuit breaker

A current limiting device includes first and second contact members, each contact member having, at a first end, contacts defining a contact pair; a contacting pressure is applied to said contact pair; and a cylindrical insulator cylindrically surrounding the contacts when the contacts are closed. The device is arranged such that at least one of the first and second contact members is rotatably supported at a second end. Also, an electrical path is defined through which currents flow in substantial opposition to the first and second contact members and in opposite directions to each other. The first ends of the first and second contact members are positioned within the space defined by the cylindrical insulator in the closed contact state. The contact of at least one of the rotatably supported contact members is positioned outside of the space defined by the cylindrical insulator when the contacts are open.

Current limiting device and circuit interrupter having a current limiting function

A switch having a molded article of which the entirety or a part is composed of an organic and inorganic complex composition is provided, wherein the base inside of the base of a box is composed of for example an organic and inorganic complex composition with the resin content at 15 to 70 wt % and the content of one or more inorganic compounds capable of dehydration at 150&deg; C. or more at 80 to 30 wt %.

Organic and inorganic complex compound and switch using same

A switch containing a switch case, contacts adapted to be opened and closed, an arc extinguishing chamber disposed in the vicinity of the contacts, and an arc extinguishing material capable of reducing the amount of metal particles and free carbons to be scattered from components disposed within the switch by an arc generated when the contacts are opened or closed or capable of insulating the metal particles and the free carbons to convert into an insulator, thereby inhibiting a decrease in arc resistance expected to occur upon the generation and extinction of the arc and a decrease in insulation resistance expected to occur within and around the arc extinguishing chamber and at inner wall surfaces of the switch case upon and after the extinction of the arc. The switch is applicable to a switch expected to generate an arc upon interruption of electric current flowing therethrough such as a circuit breaker, current-limiting device or electromagnetic contactor and is capable of immediately extinguishing the arc and inhibiting the decrease in insulation resistance within and around the arc extinguishing chamber and at inner wall surfaces of the switch case.

Switch and arc extinguishing material for use therein

A switch comprising a switch case, contacts adapted to be opened and closed, an arc extinguishing chamber disposed in the vicinity of the contacts, and an arc extinguishing material capable of reducing the amount of metal particles and free carbons to be scattered from components disposed within the switch by an arc generated when the contacts are opened or closed or capable of insulating the metal particles and the free carbons to convert into an insulator, thereby inhibiting a decrease in arc resistance expected to occur upon the generation and extinction of the arc and a decrease in insulation resistance expected to occur within and around the arc extinguishing chamber and at inner wall surfaces of the switch case upon and after the extinction of the arc. The switch according to the present invention is applicable to a switch expected to generate an arc upon interruption of electric current flowing therethrough such as a circuit breaker, current-limiting device or electromagnetic contactor and is capable of immediately extinguishing the arc and inhibiting the decrease in insulation resistance within and around the arc extinguishing chamber and at inner wall surfaces of the switch case.

A switch includes a moving element having a traveling contact at one end thereof, and a repelling element having a repelling contact at one end thereof and extending substantially parallel to the moving element, and the repelling contact capable of making and breaking contact with the traveling contact, and the switch further comprising a conductor connecting the repelling element to the side of a power source system, and the conductor including a first conductor portion positioned within the limits of the traveling contact and said repelling contact when said moving element and the repelling element are opened so as to be connected to the side of the power source system, and a second conductor portion connecting the first conductor portion to the repelling element at an end on the side opposed to the repelling contact.

Switch including a moving element, a repelling element and a conductor

A switch includes a fixed contact having a first conductor portion connected to a terminal, a second conductor portion having a stationary contact, and a third conductor portion. The third conductor portion is disposed on the side of the other end of a moving contact to which a traveling contact is not mounted with respect to a position of the stationary contact, and on the side opposed to the terminal. The first conductor portion is disposed above a contact surface of contacts at a contact closing time, and is disposed below a contact surface of the traveling contact at a contact opening time. A position of the first conductor portion which can be surveyed from a surface of the traveling contact at an opening time of the contacts is coated with an insulator. Thereby, it is possible to provide an excellent current-limiting performance since an entire current path of the fixed contact generates electromagnetic force to stretch an arc on the side of the terminal, and since the arc is cooled by vapor generated from the insulator.

High voltage switch including U-shaped, slitted stationary contact

A switch is configured that: in the closed-circuit state, at least part of its movable contact arm enters into a oblong generally hexahedral space defined by its elongated stationary conductor in its closed circuit position. Both contacting and breaking of the moving contact and the fixed contact occur in the space. Overall electromagnetic forces generated by the current flowing through the stationary conductor, movable contact arm and the arc induced at the time of breaking effectively act to extend the arc toward a terminal section of the stationary conductor and to increase the arc resistance at the time just after the breaking of both the contacts.

Electric switch gear with improved stationary contact configuration

The current limiting circuit breaker comprises a circuit breaker (1A) and at least one current limiting unit (1B); the circuit breaker (1A) has load side terminals (12) and power-source-side or connection terminals (2a), and the current limiting unit (1B) is unitized to be simply connected to the circuit breaker (1A) or to another current limiting unit (1B) at their power source side terminals; the current limiting unit (1B) has current limiting connection terminals (25a) which ride on the circuit breaker connection terminals (2a) or power-source-side terminals (20a) of another current limiting unit (1B) for connection, to the circuit breaker (1A) or another current limiting unit (1B).

Current limiting circuit breaker

In a circuit breaker of double break type, a first moving contact arm and a second moving contact arm are pivoted on a common pin shaft in a manner to move mechanically independent from each other and are electrically connected at the parts near the pivoted ends by a flexible conductor, such as a braided wires, and thereby stable and reliable contacts of the moving contacts on the stationary contacts are assured.

In a twin-contact type current limiting apparatus in which two contacts are electrically connected in series with each other, each of movable contact arms (23a, 23b) is extended in substantially parallel with and along each of stationary contact arms (21a, 18a), thereby obtaining balanced electromagnetic repulsions when an excessive current flows.

Growing community of inventors

Amagasaki, Japan

Takao Mitsuhashi