Murata Manufacturing Co., Ltd.

Masahiko Kawase

Norimitsu Kitoh

Hidenobu Kimoto

Yukiko Ueda

Norimitsu Kito

Ikuya Taniguchi

Noboru Furukawa

Yoshiyuki Yamashita

Yasunori Ito

Takehiko Ishii

Satoshi Fujita

Toshiharu Hirota

Minoru Shimada

Kiyohiro Koto

Shuji Tsubaki

Yoichi Kawase

Kingo Ohmura

Atsuo Yokota

Satoshi Kakihara

Kenji Nagareda

Makoto Matsubara

Ryoichi Urahara

Mitsuaki Fujimoto

Shiro Tsuji

A thermistor includes a thermistor body and terminal electrodes disposed at both ends of the thermistor body. A first lead is longer than a second lead. The first and second leads include tips having inclined shapes that are cut such that metal lines are surface-exposed, respectively. The thermistor body is attached at a predetermined side position of the first lead such that the first lead and a side folding portion of the terminal electrode form a predetermined angle &#x3b8;. The terminal electrode and the first lead are connected to each other through solder, and the second lead and the terminal electrode are connected to each other through solder. This can prevent the occurrence of damage even if an excessive thermal stress is applied. The temperature sensor with leads having stable electric connection with the temperature sensor that has satisfactory detection sensitivity and high reliability is achieved.

Temperature sensor with leads

A lamination-type resistance element includes a laminated sinter having internal electrodes of a first group and internal electrodes of a second group, the first internal electrode group including a plurality of internal electrodes facing each other through a ceramic resistance layer and defining a resistance unit at the portion where the plurality of internal electrodes face each other. A first end of the resistance unit is connected to a first external electrode and the second end is connected to a second external electrode. The second internal electrode group includes a plurality of pairs of internal electrodes in which the inner ends face each other through a gap on the same plane inside the laminated sinter, and a plurality of pairs of gaps in the plurality of internal electrodes are arranged at the same location when seen from one end of the lamination direction of the laminated sinter. Thereby, fine adjustment of a resistance value can be performed.

Lamination-type resistance element

A method of manufacturing a chip-type ceramic electronic component having stable electrical properties and excellent mechanical strength includes the steps of providing a plurality of green sheets having predetermined cutting positions, coating inorganic paste including the same ceramic material as that included in ceramic green sheets, and an inorganic material having higher resistivity than that of the ceramic material, on a region of each ceramic green sheet, and laminating a predetermined number of the ceramic green sheets to form a ceramic laminated product. Then, the ceramic laminated product is cut into a chip at the predetermined cutting positions and sintered to form a ceramic sintered compact, and external electrodes are formed at both ends of the ceramic sintered compact.

Method of manufacturing chip-type ceramic electronic component

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

Thermistor chips are produced by preparing thermistor bodies each having outer electrodes formed on its end parts and dipping them in a solvent so as to melt away exposed surface portions of the thermistor body. In order to efficiently adjust their resistance values so as to produce thermistor chips with resistance values having only small variations from a target value, the resistance value between the outer electrodes are measured for each and they are divided into ranks according to the measured resistance values, and the dipping process is carried out differently for different ranks such that different amounts of the thermistor body material will be melted away.

Method of producing thermistor chips

A negative temperature coefficient thermistor includes a thermistor element containing a transition metal oxide as a main component; internal electrodes disposed in the thermistor element; and external electrodes, electrically connected to the internal electrodes. A method for manufacturing such a thermistor includes providing green ceramic sheets for forming the thermistor element; applying a conductive paste for forming the internal electrodes onto some of the green ceramic sheets to form internal electrode layers; stacking the green ceramic sheets and the green ceramic sheets with the paste to form a green compact; firing the green compact to obtain a fired compact; and forming the external electrodes.

Negative temperature coefficient thermistor and method for manufacturing the same

An inductor obtained by laminating a plurality of ceramic layers having an internal coil conductor, and a thermistor obtained by laminating a plurality of ceramic layers having internal electrodes and having a predetermined resistance-temperature characteristic are laminated via an intermediate insulating layer. Both ends of the internal coil conductor of the inductor and the internal electrodes of the thermistor are connected to a pair of external electrodes. Thus, the inductor and the thermistor are connected in parallel.

Chip-type composite electronic component and manufacturing method thereof

A chip thermistor has a pair of outer electrodes opposite each other with a specified distance in between on one of the surfaces of a thermistor element and an inner electrode extending inside the thermistor element so as to overlap these outer electrodes in the direction perpendicular to the surface on which the outer electrodes are formed. An electrically insulating layer is preferably formed on the same surface as and between the pair of outer electrodes. Each of the outer electrodes may be formed with two or more layers, the outermost of the layers being of gold. The resistance value of such a chip thermistor can be adjusted by abrading at least a portion of the edges of the thermistor element together with portions of the outer electrodes.

Method of producing chip thermistors

A resistor element has a ceramic body with a first outer electrode and a second outer electrode formed on its mutually opposite externally facing end surfaces and a plurality of mutually oppositely facing pairs of inner electrodes inside the ceramic body. Each of these pairs has a first inner electrode extending horizontally from the first outer electrode and a second inner electrode extending horizontally from the second outer electrode towards the first outer electrode and having a front end opposite and separated from the first inner electrode by a gap of a specified width, these plurality of pairs forming layers in a vertical direction. The gap of at least one of these plurality of pairs of inner electrodes is horizontally displaced from but overlapping with the gaps between the other pairs of inner electrodes. For producing such a resistor element, the distance of displacement is set according to a given target resistance value intended to be had by the resistor element. Alternatively, the thickness of those portions of the ceramic body between at least one of mutually adjacent pairs of the inner electrodes is different from the thickness of the portions of the ceramic body between the other mutually adjacent pairs of the inner electrodes.

Thermister chips

Thermistor chips are produced by preparing ceramic green sheets, applying an inorganic material such as a glass paste on these green sheets in areas including lines along which they are to be later cut, stacking a plurality of these green sheets one on top of another to obtain a stacked body, obtaining chips by cutting this stacked body along those pre-specified lines and subjecting these chips to a firing process to obtain sintered bodies, and forming outer electrodes on mutually opposite end surfaces of these sintered bodies. A thermistor chip thus produced has a thermistor element having outer electrodes on its mutually opposite end surfaces, and diffused layers of an inorganic material having a higher specific resistance than material of the thermistor element. These diffused layers are formed proximally to externally exposed surfaces of the thermistor element.

The present invention is to provide a chip type electronic part without the risk of generating a tombstone at the time of soldering on a circuit substrate. External electrodes are formed at both end parts of an electronic part element, with the external electrodes comprising electrodes at the base layer formed as a thin film and solders at the outermost layer, with the solders at the outermost layer containing Sn and Pb as the main component and 0.1 to 0.4% by weight of Ag.

Chip type electronic part

Methods of producing resistor elements

A chip thermistor is produced by first preparing green sheets containing a thermistor ceramic material and an organic binder, then applying a resistor paste on one or more of these green sheets and an inner electrode paste on some others, and forming a layered structure by stacking and compressing together specified numbers of these green sheets. The layered structure is then subjected to a firing process and outer electrodes are formed on oppositely facing pair of outer end surfaces of the layered structure. The chip thermistor thus produced has a main body of a thermistor ceramic material having a specified resistance-temperature characteristic, a pair of outer electrodes on its end surfaces, at least one resistor having resistance greater than 1&OHgr;, and at least one pair of inner electrodes opposite each other and separated from each other with the thermistor ceramic material in between. The resistor and the pair of inner electrodes are connected in series or in parallel between the pair of outer electrodes.

Chip thermistors

A semiconductive ceramic is produced by sintering a semiconductive ceramic material containing a mixed powder of a lanthanum compound and a cobalt compound. The mixed powder has a specific surface area of about 3 m /g or more, an average primary particle size of about 2.0 &mgr;m or less, and an average secondary particle size of about 10 &mgr;m or less.

Growing community of inventors

Yokaichi, Japan

Masahiko Kawase