Murata Manufacturing Co., Ltd.

Kingo Ohmura

Minoru Shimada

Asami Wakabayashi

Tetsuya Kawamoto

Hiroyuki Kobayashi

Hideki Yamada

Masahiko Kawase

Shuji Tsubaki

Yoshiyuki Yamashita

Atsuo Yokota

Temperature sensors are produced by first producing temperature sensing elements each having electrodes on its mutually oppositely facing main surfaces, next forming a lead frame comprising a linearly elongated base part and a plurality of pairs of planar lead parts extending perpendicularly from said base part, twisting each of these planar lead parts such that each of the pairs has top end parts which face each other with a gap therebetween, inserting one of the temperature sensing elements between the mutually facing top end parts of each pair in the corresponding gap and electrically connecting the electrodes on the inserted temperature sensing element individually to the top end parts of the corresponding pair, and cutting each of the planar lead parts from said base part to form lead terminals of specified lengths for the temperature sensors. Each of the planar lead parts is provided with a semicircular kinked part distal from the top end part such that the kinked parts of each of the pairs of planar lead parts are bent in a same direction with respect to each other and in a side-by-side relationship.

Method of producing temperature sensor and mounting same to a circuit board

A temperature sensor has lead lines made of an elastic material each attached to a corresponding one of electrodes on a temperature sensing element such as an NTC thermistor element. The lead lines may each have a non-straight part where they are bent or deformed into a semi-circular shape such that, when these lead lines are inserted into throughholes prepared through a circuit board, the non-straight parts are hooked at the throughholes and the portions of the lead lines above the circuit board will stand up obliquely. Instead of lead lines, a pair of elongated planar lead terminals each with a twisted top end part may be connected to the electrodes such that the top end parts of the pair of lead terminals face each other and can support the temperature sensing element more securely in between.

Temperature sensor

A fluorescent lamp lighting device includes a fluorescent light bulb having an electrode filament and an electronic lighting circuit substrate for lighting the fluorescent light bulb, wherein a capacitor connected in parallel with the fluorescent light bulb, a positive characteristic thermistor connected in parallel with the capacitor, and a negative characteristic thermistor connected in parallel with the electrode filament are mounted on the electronic lighting circuit substrate, and wherein the negative characteristic thermistor, having a mounting surface, is mounted in such a manner that the mounting surface is in abutment with the electronic lighting circuit substrate. The positive characteristic thermistor and the negative characteristic thermistor are preferably mounted on mutually different mounting surfaces among the two mounting surfaces of the obverse and reverse surfaces of the electronic lighting circuit substrate.

Fluorescent lamp lighting device

It is an object of the present invention to provide an improved negative temperature coefficient thermistor capable of increasing an adhesion strength between a negative temperature coefficient thermistor element consisting of LaCoO.sub.3 rare earth transition element oxide on one hand and electrodes on the other, thereby improving a reliability of the thermistor product. The negative temperature coefficient thermistor of the present invention is obtained by forming electrodes on the surface of a negative temperature coefficient thermistor element consisting of LaCoO.sub.3 rear earth transition element oxide. Such electrodes are formed by adding one or more kinds of oxide powders of Ni, Cr, Mn and Fe in a metal powder, with the content of the oxide powders in the metal powder being 1.0 wt % or less (however, not including 0 wt %).

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Shiga, Japan

Kingo Ohmura