| 摘要 |
PURPOSE:To prevent wrong detection of presence of paper due to an influence of external light incident from an insertion port when a paper accommodating means is removed from a paper feed part, in the captioned device detecting presence of paper in the paper accommodating means removably provided in the paper feed part. CONSTITUTION:If paper P in a paper cassette 2 mounted to a paper feed part 1a is all fed out, emitted light from a light emitting element 5a is not reflected by the paper P and not received by a light receiving element 5b to turn off a switching transistor 20. In consequence, an input line 22 holds a level H and a control unit 23 decides no presence of paper to output a control signal to a display device 24 and copying mechanism 25. While if the operator extracts the cassette 2, a swinging lever 11 is turned by a spring 12 to displace a paper feed roller 3 diagonally upward. Further a crank lever 16 is simultaneously turned, and a sensor 5 mounted to said lever 16 is tilted to prevent reception of external light incident from an insertion port 1b. |
