| 摘要 |
<p>APPARATUS AND METHOD FOR CONTROLLING THE POSITION OF A ROTARY HEAD The position of a rotary head which is mounted on a deflection device is controlled as the head scans successive tracks on a record medium. Tracking drive signals are generated as a function of the deviation of the head relative to a track scanned thereby, such tracking drive signals representing the configuration of that track relative to a trace scanned by the head. The tracking drive signal is sampled at successive locations along the trace to produce successive samples as the head scans the track. Previously stored samples are compared to the successively produced samples, and any difference between compared samples is used to correct the stored sample by a predetermined amount irrespective of the actual difference between the produced and stored samples. Thus, the stored samples are successively corrected; and the corrected samples are returned to the storage device from whence they came. Hence, the stored samples gradually are corrected to represent the configuration of the tracks scanned by the rotary head. When the head reproduces signals from the record medium, the generated tracking drive signals are used to control the deflection device so as to make the head coincident with the track being scanned thereby. When the head is used to record signals, the stored samples are used to control the deflection device before such samples are corrected. In one embodiment wherein the head is used for recording, the stored samples are compared to reference samples, whereby the stored samples gradually are corrected to conform to the reference samples, and the stored samples also are used to control the deflection device so that the traces scanned by the head gradually conform to the configuration represented by the reference samples. -ii-</p> |
