| 摘要 |
1,049,594. Automatic speed control. RANK BUSH MURPHY Ltd. April 29, 1965 [April 29, 1964], No. 17691/64. Heading G3R. A transducer 2 yields a train of pulses which, when member 1 is moving in a desired manner, have the same frequency and phase as a train of reference pulses from source 4. Comparator 3 provides a phase-error signal which is applied to delay device 5 in which the signal is stored until the error signal resulting from the next subsequent measurement is available. The delayed and undelayed signals are applied to difference circuit 6 to develop an error difference signal which is combined with a delayed feedback signal in adder 7. The latter develops a velocity error signal proportional to the sum of one-half the error difference signal added to the delayed feedback signal. In adder circuit 8, the velocity error signal is combined with the phase error signal to develop a first control potential proportional to the sum of one-half the velocity error signal and the phase error signal. The first control potential is then applied to a non-linear circuit 9 which has a linear response to signals of either polarity within a predetermined range of magnitude, and, for signals exceeding this range, has an incremental gain which continuously diminishes as the magnitude of the signal increases. The output from circuit 9 forms a second control potential which is added to the velocity error signal in circuit 10 to yield a final control potential. The latter is applied to motor 11 which drives the member 1, a device 13 being responsive to the force in transmission 12. The signal from the device 13 is delayed until the next measurement period by device 14 and is then applied as the delayed feedback signal to the circuit 7. The transducer 2 may be magnetic or photo-electric, and the force in transmission 12 may be detected by a load cell or by means responsive to the armature current of the motor. |
