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:
Sep. 13, 1994
Filed:
Feb. 17, 1993
Applicant:
Inventors:
Assignee:
TDK Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01F / ;
U.S. Cl.
CPC ...
336 83 ; 336134 ; 336136 ;
Abstract
The variable inductance coil device having an outer magnetic member, a bobbin member, a coil member and an inner magnetic member. A female thread (thread portion) is provided in the inner periphery of the tube of the bobbin member, and a male thread (thread portion) which meets with the female thread of the tube is provided in the outer periphery of the inner magnetic member. The inductance varies accurately by rotating and moving the inner magnetic member. Since the outer magnetic member is formed in the closed shape, the leakage flux can be lowered.