Patent ID: 8550583
Filing Date: 2013-10-08
Classification: B41J

Abstract:
1. An image forming apparatus, comprising: a carriage configured to travel with a recording head configured to eject liquid droplets being mounted thereon; a first encoder including a first encoder scale placed along a traveling direction of the carriage and a first encoder sensor configured to read the first encoder scale; an antiphase member configured to travel in opposite phase from the carriage; a second encoder including a second encoder scale placed along a traveling direction of the antiphase member and a second encoder sensor configured to read the second encoder scale; and a control part configured to control a travel of the carriage in accordance with a detection result of the first encoder and a detection result of the second encoder; wherein said image forming apparatus is configured to count a first detection pulse and a second detection pulse said first detection pulse being from said first encoder and obtained at an acceleration and deceleration region of said carriage, and said second detection pulse being from said second encoder and obtained at a uniform-speed region of said carriage; and wherein said image forming apparatus is configured to switch from using one of said first encoder and said second encoder to using the other of said first encoder and said second encoder.