| 摘要 |
<p>PURPOSE:To adjust the positioning speed of an information retrieving device freely with the pushing force of an operator by varying the driving state of a driving means according to the pushing force to a switch which is is turned on and off by depression. CONSTITUTION:A film F is clamped and necessary key pads 21-24 on the keyboard of a controller are pressed so that a desired frame is projected on a screen 11. Variation in the resistance value of a pressure sensor 27 for them is detected as a voltage value, which is amplified by amplifiers 431-434 to a necessary voltage level. This voltage value is converted by an A/D converter 45 into a digital value, which is read in a CPU41. The CPU41 supplies a motor driving circuit 46 with a short-period pulse when outputs from the respective pressure sensors 271-274 are large or a long-period pulse output when small according to a program written previously in a ROM42 to drive corresponding pulse motors MX, MY, thereby moving the film F to a desired position at a specific speed.</p> |
