| 摘要 |
<p>Tape recording and playback apparatus (10) including tape head cleaning assembly (80-92) for intermittent cleaning of one or more tape head(s) mounted in the periphery (18) of a helical scanning drum (12) forming part of the apparatus (10). Loading of a cassette (24) carrying the tape, extension of the tape (20) by movable guides (44,46) into contact with the drum periphery (18), and movement of a pinch roller (50) are controlled by a motor-driven cam (40) as described in EP0782136-A1. Instead of also using the prior art cam to control tape tension, this is now done by dynamic braking of the motor (30) for the tape supply reel (26). In accordance with the invention, the fourth control function of the prior art cam is now utilised for selective mechanical actuation of a swinging arm (82) on which is mounted an abrasive cleaning wheel (80). Rotation of the control cam (40) to its "fourth function" position allows the arm (82) to pivot and thus brings the abrasive wheel (80) into temporary contact with the periphery (18) of the helical scanning drum (12) so as to remove debris clogging the tape head(s). High performance of the data recording/playback unit (10) is maintained by the inventive adaptation of existing hardware (40) to effect intermittent operation of a tape head cleaner (80) built-in to the unit (10). <IMAGE></p> |
