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:
Apr. 26, 2016
Filed:
Mar. 07, 2012
Takashi Yamakawa, Ibi-Gun, JP;
Yasuhiro Ishii, Ibi-Gun, JP;
Daisuke Minoura, Ibi-Gun, JP;
IBIDEN CO., LTD., Ogaki-shi, JP;
Abstract
A filter state detection device includes a first pressure detection part, a second pressure detection part, and a filter state determination part. The filter state determination part is configured to include an operation part and a storage part. The operation part is configured to apply Fourier transformation to each of values of first and second pressures to obtain first and second spectral intensities and/or phases at a zero frequency and first and second spectral intensities and/or phases at a predetermined frequency and configured to compare the first spectral intensity and/or phase at a zero frequency and the first spectral intensity and/or phase at the predetermined frequency as a first group against the second spectral intensity and/or phase at a zero frequency and the second spectral intensity and/or phase at the predetermined frequency as a second group to determine a state of a filter.