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:
Jan. 08, 1985
Filed:
Jun. 12, 1981
Daishiro Hayakawa, Ashiya, JP;
Masao Akimoto, Neyagawa, JP;
Katsumi Narita, Neyagawa, JP;
Kenroku Tani, Katano, JP;
Matsushita Electric Industrial Co., Ltd., Kadoma, JP;
Abstract
Comb filter having a comb like band pass characteristic curve by using an ultrasonic delay line (9) is improved to reduce its size. An input signal is given through an impedance element 13 to a single terminal 10a of an improved delay line 9, wherein the single terminal serves as the input terminal and at the same time as the output terminal. Signals at both ends of the impedance element 13 are given to a mixing circuit 15 for summing or subtracting thereby. In the improved delay line 9, the ultrasonic wave radiated from the input terminal travels twice the conventional delay line and comes back to the original terminal, and thereby a sufficient propagation distance is obtainable in a small delay line.