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. 29, 2003
Filed:
Oct. 02, 1997
Jiro Moriyama, Kawasaki, JP;
Yoshio Uchikata, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A liquid detection method and a liquid discharging device to detect whether or not a liquid can be supplied in a state in which a liquid channel from a tank for accommodating the liquid to each discharging port of a recording head is not disconnected by a bubble. A detection-signal input terminal is provided at a position where it contacts the liquid. A detection terminal is provided at a position where it does not electrically contact the liquid and is isolated from the liquid within the tank via a lower wall of the tank, made of an insulating plastic material, and the air. An electrical signal is input from a recording apparatus to the detection-signal input terminal via a connection terminal. The input electrical signal is transmitted through the ink within the recording head, the liquid channel within a joint, and the liquid within the tank. The detection terminal, comprising a conductive metal plate provided at a position corresponding to the entire lower surface of the tank, detects the waveform of a voltage. By comparing the detected voltage with a predetermined threshold, it is determined whether or not the liquid can be normally supplied.