| 摘要 |
<p>High speed contact duplicating of a magnetic copy tape from a magnetic master tape is effected by a pair of pinch rollers for pressing the tapes together and into adhesion contact such that the air is squeezed from between the tapes and they adhere together until forcibly separated, and transfer excitation means immediately downstream from the pinch rollers to cause printing of the copy tape with minimum opportunity for shearing motion of the tapes relative to one another. The path of the tape downstream from the pinch rollers is also kept straight to minimize shearing motion, and tape cleaning means are provided upstream from the pinch rollers to augment the effectiveness of the adhesion contact. For television tapes, the audio and cue tracks may be separately read from the master and the control track from the copy and re-recorded on the copy downstream from the transfer excitation means. The tapes are separated during rewind mode. A multiple tape loop vacuum column storage bin is also provided for operation of the master tape in endless form, and the vacuum supply to the bin is servoed to control the feeding of tape from the bin to the pinch rollers. Means are also provided to make repeated copies of any selected portion of the master as by automatically stopping the copy tape at the end of the selected portion of the master, and rewinding the master to the beginning of the selected portion.</p> |
