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:
Oct. 16, 2007
Filed:
Jul. 12, 2005
Sadao Omata, Tokyo, JP;
Sadao Omata, Tokyo, JP;
Nihon University, Tokyo, JP;
Abstract
To be able to detect a displacement amount of a moving object by a resolution of from micrometer to nanometer by a simple structure. An excitation coiland a detection coilare arranged to align and a magnetic body probein a conical shape a sectional area of which is change in a longitudinal direction is arranged in a state of being inserted into an air core portion of the excitation coil. An output terminal from the detection coilis connected to an amplifierand a phase shifting circuitis provided between the amplifierand an input terminal of the excitation coil. When the probeof the magnetic body is moved at inside of the air core portion of the excitation coil, inductance of the excitation coilis changed, a phase difference is produced between an input signal inputted to the excitation coiland an output signal outputted from the detection coiland the phase shifting circuitchanges a frequency to nullify the phase difference. The displacement amount is detected from the frequency deviation at this occasion.