摘要 |
PURPOSE:To make it possible to surely wind up or off a film at a high speed, by controlling the rotational speed of a servo-motor irespective of the specific rotational speed of a pulse generator. CONSTITUTION:A speed detecting circuit 40 receives and counts pulse signals PS transmitted from a pulse generator 3 to obtain the rotational speed of a servo- motor 1, and issues a switching signal SW to a switching circuit 41 in accordance with the value of the rotational speed with respect to a set value which is determined in accordance with the specific speed of a pulse generator 8. That is, when the rotational speed of the servo-motor 1 is below a predetermined value, the switching signal SW turns on a contact 41A so that belts 4, 11 are transferred and pressed to the outer surface of a rolled film 20 to wind up the latter onto a reel 21. When the rotational speed of the servo-motor 1 is above the predetermined value, the switching signal SW turns off the contact 41A to stop the introduction of the pulse signals so that erroneous operation due to irregular pulse trains is prevented, thereby the search of the film is surely made at a high speed. |