Murata Manufacturing Co., Ltd.

Shinichi Madokoro

Yukio Sakamoto

Shingo Okuyama

A chip-like LC filter which comprises a cylindrical magnetic element having a through hole. A cylindrical capacitor element has a through hole and terminal electrodes formed on inner and outer peripheral surfaces thereof. A central conductor is inserted in the through holes of the magnetic element and the capacitor element, which through holes are aligned along an axial direction. The terminal electrode on the inner peripheral side of the capacitor element is electrically connected with the central conductor. Cap-shaped external terminal members are respectively provided on both end portions of the central conductor, so that the magnetic element and the capacitor element are located between the external terminal members. The central conductor is obtained by cylindrically rolling a metal plate, so that a portion located on the outer periphery of the rolled metal plate defines an elastic contact portion which elastically comes into pressure contact with the terminal electrode on the inner peripheral surface of the capacitor element.

Chip-like LC filter

A chip-like LC filter which comprises a cylindrical magnetic element having a through hole, a cylindrical capacitor element having a through hole and terminal electrodes formed on inner and outer peripheral surfaces thereof, and a central conductor inserted in the through holes of the magnetic element and the capacitor element aligned in the axial direction. The terminal electrode on the inner peripheral side of the capacitor element is electrically connected with the central conductor. Flange-shaped external terminal members are respectively provided on both end portions of the central conductor, so that the magnetic element and the capacitor element are located between the external terminal members.

A manufacturing method for a LC filter (an inductive filter) suitable for use as a noise filter, constituted by the steps of: inserting a central conductor into a cylindrical magnetic substance having electrodes on at least the end faces; dipping the central conductor and magnetic substance into molten solder to solder the electrodes to the central conductor; thereafter inserting the magnetic substance and central conductor into a cylindrical capacitor of a cylindrical dielectric which is provided on the inside and the outside with electrodes and on the outer peripheral surface a cylindrical eyelet member fitted thereon; sealing openings at both ends of the cylindrical capacitor by use of sealing members fitted onto the central conductor after the magnetic substance through which the central conductor passes is inserted into the cylindrical capacitor; then dipping the cylindrical capacitor into molten solder to solder the external electrode and the eyelet member; and remelting the solder for connecting the electrodes on the magnetic substance with the central conductor by the heat applied thereto when the capacitor is dipped into the molten solder, thereby connecting the electrodes on the magnetic substance with the internal electrodes on the cylindrical capacitor to complete the LC filter.

LC filter manufacturing method

A noise filter wherein a glass plate is fixedly provided in hermetic condition in a metal casing through which a central conductive member passes, a magnetic core is inserted into said central conductive member at one side of said glass plate, a pair of capacitors are respectively passing through the central conductive member at the side of said magnetic core and at the other side of said glass plate, and an insulative resin is filled at least in the opening side of the metal casing.

Growing community of inventors

Kyoto, Japan

Shinichi Madokoro