Murata Manufacturing Co., Ltd.

Yoshihiro Yamada

Haruo Takahata

Norihiro Mochida

Yuichi Takaoka

Takashi Shikama

Hisao Enomoto

Masahito Mihara

Shigehiro Ichida

A positive thermistor device used in a motor activating circuit device of a refrigerator for example includes a positive thermistor element having a pair of opposed electrodes, each of which receives compressive force elastically applied from a corresponding one of spring contact members to hold the thermistor element at a predefined position in the device. When the thermistor device is destroyed, the element breaks into fragments, some of which remain in contact with the spring contact members. The remaining fragments deviate in position to ensure that they do not conduct electricity, resulting in an open state, wherein any current flow is inhibited through such fragments. More specifically, a positive thermistor disk is held within the device so that it is interposed between conductive spring contact pieces and insulative position-alignment projections, which are cross-diagonally situated with respect to each other. The spring contact pieces are located further toward the periphery of the disk than the position-alignment projections, causing a spring force to extend in a direction generally outward relative to a direction perpendicular to the planes of the electrodes. In one embodiment, the position-alignment projections have cut-away portions at outer tip ends thereof respectively to further promote the formation of an open circuit state upon the occurrence of malfunction.

Motor activating circuit device and refrigerator

A positive thermistor device includes a positive thermistor element having a pair of opposed electrodes, each of which receives compressive force elastically applied from a corresponding one of spring contact members to hold the thermistor element at a predefined position in the device. When the thermistor device is destroyed, the element breaks into fragments, some of which remain in contact with the spring contact members. The remaining fragments deviate in position to ensure that they do not conduct electricity, resulting in an open state, wherein any current flow is inhibited through such fragments. More specifically, a positive thermistor disk is held within the device so that it is interposed between conductive spring contact pieces and insulative position-alignment projections, which are cross-diagonally situated with respect to each other. The spring contact pieces are located further toward the periphery of the disk than the position-alignment projections, causing a spring force to extend in a direction generally outward relative to a direction perpendicular to the planes of the electrodes. In one embodiment, the position-alignment projections have cut-away portions at outer tip ends thereof respectively to further promote the formation of an open circuit state upon the occurrence of malfunction.

Electronic component

Electronic devices having reduced destruction of internal elements upon

In a positive temperature coefficient thermistor, a terminal holding member is provided between an outer casing and an elastic terminal electrically connected to the semiconductor ceramic element. The terminal holding member is formed of a thermoplastic resin having a low softening point. Consequently, when an abnormally large amount of heat is generated in the semiconductor ceramic element, the terminal holding member melts and deforms, causing the semiconductor ceramic element to be separated and thereby electrically disconnected from the terminal.

Electronic part such as PTC thermistor and casing for the same with a

A circuit for starting a single-phase AC induction motor 11 having a main winding 12 and an auxiliary winding 13, which is so constructed that a PTC element 16 and a triac 17 are connected in series with the auxiliary winding 13 and a gate voltage of the triac 17 is reduced to turn a portion between main terminals of the triac 17 off after a predetermined time period has elapsed since the motor 11 was started, and can effectively lower the power consumption without degrading starting characteristics and can shorten return time required until the motor 11 is restarted and lengthen the life of the PTC element 16.

Circuit for starting single-phase AC induction motor

A PTC thermistor device includes a case in which a holding plate made of metallic material is vertically arranged; and on each of both main surfaces of the holding plate, an electrode from a respective one of two PTC thermistor units is fixed. Therefore, the two PTC thermistor units are thermally coupled with each other through the holding plate. A terminal is integrally formed at the lower end of the holding plate, which is exposed outside the case. A throughhole for reducing an area of a section of a heat conduction path from the holding plate to the terminal is formed in the heat conduction path.

PTC thermistor device with PTC thermistor unit housed in case

A positive temperature coefficient thermistor device has a case, a positive temperature coefficient thermistor element which is disposed in the case, a pair of first terminals which is disposed in the case to be in contact with corresponding electrodes of the thermistor element, a pair of second terminals which is disposed on the case and is associated with the first terminals, and pin members electrically and mechanically connecting the first terminals with the second terminals through an outer wall of the case.

Growing community of inventors

Nagaokakyo, Japan

Yoshihiro Yamada