Murata Manufacturing Co., Ltd.

Haruo Takahata

Yoshihiro Yamada

Norihiro Mochida

Katsuyuki Uchida

Takayo Katsuki

Shyoji Asida

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

A PTC thermistor including ceramic body having a positive temperature coefficient of resistivity, a pair of electrode layers provided on both major surfaces of the ceramic body so as to be opposed to each other with the ceramic body interposed therebetween, a ceramic reinforcing plate provided on at least one of the major surfaces of the ceramic body, and an output electrode having a connecting portion for making electrical connection with the electrode layer on an inner major surface of the ceramic reinforcing plate and extending to an outer major surface of the reinforcing plate from the connecting portion.

PTC thermistor

In an organic positive temperature coefficient thermistor first and second power supplying portions are arranged spaced apart from each other by a predetermined distance on a sheet made of a material exhibiting a positive temperature characteristic of resistance. A respective plurality of branch-shaped electrodes is connected to each of the first and second power supplying portions. The plurality of branch-shaped electrodes connected to each of the power supplying portions is arranged so as to extend toward the side of the other power supplying portion. The branch-shaped electrodes connected to each of the power supplying portions are arranged so as to be interdigitated with the branch-shaped electrodes connected to the other power supplying portion. The organic positive temperature coefficient thermistor is characterized in that at least one of the first and second power supplying portions is constituted by a plurality of power supplying electrodes which are insulated from each other. A plurality of branch-shaped electrodes is connected to each of the plurality of power supplying electrodes, and they are distributed along the power supplying electrodes with a predetermined spacing and with a predetermined ratio between the respective members of branch-shaped electrodes on each of the power supplying electrodes.

Organic positive temperature coefficient thermistor

An organic positive temperature coefficient thermistor in which a plurality of spaced, substantially parallel conductive portions extend between first and second opposed side edges of a sheet made of a material, exhibiting a positive temperature characteristic of resistance, which is composed of conductive particles disposed in an organic polymer material. The conductive portions may also extend between the vicinities of the side edges. A plurality of insulating layers are formed so as to alternately coat the vicinities of respective first ends of the conductive portions at the first or second side edges or in the vicinity of the side edge. First and second power feeding electrodes are respectively formed along the first and second side edges so as to extend on the insulating layers and on the conductive portions located between the insulating layers to electrically connect the respective ends of the conductive portions.

Growing community of inventors

Nagaokakyo, Japan

Haruo Takahata