| 摘要 |
PROBLEM TO BE SOLVED: To surely restrain generation of an erroneous detection of holding-in of a window pane by compensating a pulse width through the comparison between a signal logic when a pulse signal is changed and a pulse logic after the lapse of a specified time, thereby obtaining a pulse cycle. SOLUTION: A relay drive circuit 8 and a relay circuit 8a normally and reversely drives a motor M to move a window pane up and down. A pulse sensor 10 outputs a pulse signal Sp having a pulse cycle proportional to the motor M speed. A controller 2 moves the motor M to a direction where the window pane is opened by a specified amount when a sum of cycle difference between an average pulse cycle and the pulse cycle exceeds a threshold value. The controller 2 determines that a normal pulse signal Sp change has occured when a signal logic after the lapse of mask period after the pulse signal Sp is changed differes from the preceeding one. Accordingly, chattering in the pulse signal Sp can be corrected, thereby surely detecting the existence of holding-in of window pane. |
