Patent ReferencesTracking control circuit using a delayed tach signal Speed and phase control system VTR Tape drive system Digital servo circuit Slow or still mode video signal reproducing apparatus with incremented tape movement Method of positioning reproducing elements and device for carrying out the method Patent #: 4303953 InventorsAssigneeApplicationNo. 06/422711 filed on 09/24/1982US Classes:318/258, And braking318/763Reversal of power to primary windingExaminersPrimary: Truhe, J. V.Assistant: Ro, Bentsu Attorney, Agent or FirmInternational ClassesG11B 15/18 (20060101)G11B 15/20 (20060101) H02P 7/06 (20060101) H02P 3/06 (20060101) H02P 3/08 (20060101) H02P 23/00 (20060101) G11B 15/467 (20060101) G11B 15/46 (20060101) G11B 15/54 (20060101) G11B 15/48 (20060101) Foreign Application Priority Data1981-09-25 JPAbstractA control circuit for a DC capstan motor used for driving a tape having control signals thereon is adapted for accurate stopping of the tape during intermittent-motion operation. A frequency generator coupled to the motor generates a frequency signal whose frequency is proportional to the motor's speed. A position signal generating circuit generates a position value that increments by steps upon occurrences of the frequency signal. A clamp circuit clamps the position value to a clamping level upon detection of the control signals. A brake start signal generator provides a brake start pulse signal when the position value exceeds a predetermined threshold, and this brake start pulse signal is used to commence braking of the motor. In order to permit accurate stopping in both forward and reverse directions, the clamping circuit provides one clamping level when a forward mode is selected and another clamping level when a reverse mode is selected. | |