The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 1991
Filed:
Aug. 22, 1990
Noboru Takada, Tsurugashima, JP;
Masami Osawa, Tsurugashima, JP;
Toko Kabushiki Kaisha, Tokyo, JP;
Abstract
A helical filter is provided which includes a plurality of coupled helical coils each wound around one of a plurality of substantially parallel elongated bobbins having first and second end portions. Each of the coils has an open end at a first end thereof and a grounded end at a second end thereof. A moving member for adjusting the resonance frequency of the filter is provided at the first end portion of one of the bobbins, and a bandwidth-adjusting screw is provided in the hollow interior region of one of the bobbins at the second side thereof. The screw is accessible from the second end portiion of the bobbin so as to be rotated for adjustment of the bandwidth of the filter. The bandwidth-adjusting screw is disposed at the grounded second end of the helical coil wound around the hollow bobbin.