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:
Jun. 13, 1989
Filed:
Jan. 28, 1988
Wataru Ogura, Nagano, JP;
Chinon Kabushiki Kaisha, Nagano, JP;
Abstract
A serial dot matrix printer is provided with a slit encoder and an optical sensor opposed to the slit encoder. In the slit encoder, firing signal slits each having a fixed width are provided at a fixed pitch, and block signal slits each having a width smaller than that of each firing signal slit are provided in every block composed of a plurality of the firing signal slits. As a carriage moves, the optical sensor moves along the slit encoder to produce a signal at every slit. The signal from the optical sensor is applied to a first control device having a block detector and a firing timing unit. The block detector receives the signal from the optical sensor, measures the passing time between every slit, and detects a block signal according to a difference in passing time between the slits. The firing timing unit produces firing timing signals obtained by equally dividing the passing time of each of the firing signal slits by a predetermined number whenever the passing time of the each firing signal slit is measured. There is further provided a second control device having a carriage controller for controlling a carriage moving motor according to the block signal.