| 摘要 |
<p>PURPOSE:To obtain a mechanism for advancing and retreating a head base for recording and reproducing to and from a tape surface of a cassette tape without using a solenoid by providing the mechanism for advancing and retreating the head base to and from the tape surface of the cassette tape and a lock mechanism to the head base. CONSTITUTION:When a motor 2 is rotated in the forward direction, its driving power is transmitted in turn to a small diameter pulley 5 which is coaxial with the motor, a belt 6, a fly-pulley 8 and a fixed gear 9. Then, when a turning cover 10 which is coaxial with the fixed gear 9 is turned, an idle gear 11 which is always meshed with said fixed gear is meshed along an internal gear 13, so that the idle gear is given strong driving force. Consequently, a play arm 17 is pushed up around its fitting axis 18 by a protrusion 12 of the turning lever 10, the protrusion 12 pushing up a tip part 171 of the arm, which catches the protrusion, to pass through. Then, a recess 192 of the head base 16 is pushed up by a protrusion 191 of the play arm 17 in some overstroke to be caught, so that the lock mechanism is locked up. By this method, magnetic heads 161 and 162 are advanced until their positions of abutting the tape surface C1 of the cassette tape C to be fixed there.</p> |
