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. 30, 2002
Filed:
Nov. 06, 2000
Noboru Tamura, Nagano, JP;
Hiroaki Tojyo, Nagano, JP;
Atsushi Kobayashi, Nagano, JP;
Hitotoshi Kimura, Nagano, JP;
Yoshiharu Aruga, Nagano, JP;
Takashi Mano, Nagano, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
An ink storage chamber has an indicator formed from magnetic material. A float member whose upper position is limited is housed in the ink storage chamber. Two magnetic-field detection system are provided at a position on the exterior of a sub-tank at which the detection system can detect a magnetic flux of the indicator simultaneously, such that the longitudinal direction of the detection system is oriented vertically with a specified ink level of the sub-tank sandwiched between the detection system. On the basis of signals output from the magnetic-field detection system, it is determined whether the ink level is in any one of an excessively low ink level state, a state in which injection of ink must be started, a state in which injection of ink must be stopped, and an excessively supplied state. Thus, an ink level in the sub-tank can be controlled within a specific range without involvement of an undesired increase in the number of sensors.