| 摘要 |
<p>A magnetic-tape apparatus a switching device for actuating the recording switch (52). The magnetic-tape appratus is provided with a head-mounting plate (6) which carries a magnetic head (8,9) and which is movable between at least two positions, two winding spindles (2,3) each coaxially connected at its lower end to an associated reel disc (4,5), and an idler wheel (27) which is driven by a drive means (16,17), and which is pivotally supported between the reel discs (4,5), so as to be displaceable into engagement with either disc to transmit drive thereto in an operating position of the head-mounting plate (6). The head-mounting plate (6) is provided with two abutments (34) which, in a rest position of the head-mounting plate (6), limit the displacement of the idler wheel (27) so as to keep the idler wheel (27) disengaged from the reel discs (4,5). The switching device comprises a guideway (30,31,32) on the head-mounting plate (6) which, in a movement of the head-mounting plate (6), guides an axially displaceable coupling wheel (35) between two positions. In one of these positions, when the head-mounting plate (6) is in the rest position, the coupling wheel (35) is coupled to the idler wheel (27), and in the other position, when the head-mounting plate (6) is in the operating position, the coupling wheel (35) is disengaged from the idler wheel (27). The switching device further comprises a servo wheel (40) which can be driven by the coupling wheel (35) and with which a latching element (42) cooperates to lock the servo wheel (40) against rotation in one direction and which is also cooperable with the recording switch (52) of the switching device via an actuating means (49). </p> |
