| 摘要 |
PROBLEM TO BE SOLVED: To provide a detection sensor capable performing of coarse/fine adjustment for detection sensitivity, without need to have a plurality of volumes. SOLUTION: The detection sensor according to the present invention can change its detection sensitivity by operation of a sensitivity volume 20 to change a threshold level. A trigger interval of a pulse signal outputted from an encoder 21 by rotating the sensitivity volume 20 is measured by a CPU50. When the interval t of the measured trigger signal (t=t1, t2, t3, t4,...) is shorter than a predetermined intervals t', it is considered that operation of the sensitivity volume 20 should be coarse control, and the CPU50 changes a threshold whenever it detects a trigger signal from the encoder 21. On the other hand, when the interval t of the measured trigger signal (t=t1, t2, t3, t4,...) is longer than the predetermined intervals t', the CPU50 changes the threshold whenever it detects a predetermined number of trigger signals from the encoder 21. COPYRIGHT: (C)2006,JPO&NCIPI |
