Patent ID: 8235610
Filing Date: 2012-08-07
Classification: B41J

Abstract:
1. A printing apparatus for printing on a printing medium using a printhead comprising: a first conveyance roller for conveying the printing medium; a second conveyance roller, provided at a downstream side from said first conveyance roller with respect to a conveyance direction of the printing medium, for conveying the printing medium; a first encoder configured to output a first signal in accordance with a rotation of said first conveyance roller for obtaining conveyance information based on the first signal; a second encoder configured to output a second signal in accordance with a rotation of said second conveyance roller for obtaining conveyance information based on the second signal; and a control unit, having a first counter for counting pulses included in the first signal and a second counter for counting pulses included in the second signal, configured to control conveyance of the printing medium on the basis of the count value of the first counter or the count value of the second counter, wherein in a case where the printing medium is conveyed in a direction from said first conveyance roller to said second conveyance roller, said control unit switches from the count value of the first counter to the count value of the second counter for conveyance control, based on a position of a trailing edge of the printing medium, and said control unit takes over the count value of the first counter, based on a phase difference between the first signal and the second signal, for subsequent conveyance control for which the count value of the second counter is used.