| 摘要 |
PURPOSE:To accurately detect various kinds of papers, by using a reflective type photosensor and discriminating the kind of paper by comparing the output thereof with data preliminarily stored corresponding to the kind of the paper. CONSTITUTION:The paper of an upper cassette is fed to the position of a sensor by the rotation of a call-out roll 10 and an upper paper feeder CL is once turned OFF at said position to stop paper. At this time, the terminal of a light emitting part LED1a is fallen to a LOW level to emit light from an upper sensor LED and, in order to stabilize the light emission of LED and to suppress the curling of the paper at the leading end thereof, slight timing is taken to enter paper detection processing. Herein, the output of the sensor is subjected to A/D conversion and the converted data is compared with the threshold value of paper quality guided from the output characteristic of the paper to perform the judgement of the paper while this judge result is saved in the buffer for the upper cassette of data memory. The judgement of paper quality is performed by comparing the reference value (the output of a light receiving part by said paper) at every sheet of paper and actual data. |
