摘要 |
A control arrangement for vibratory conveyors, including bowl and linear types, in which the vibration frequency is set by the behavior of the conveyor and not by an applied frequency. A sensor, SC, senses the behavior of the conveyor and a frequency, of controlled amplitude and phase, is derived from the sensor output to energize conveyor drive means, AV and AH1 to AH3. User controls (HA, VA, PA) for amplitude and phase can be mark/space adjusters (HMS, VMS, DMS) effective on the base circuits of transistors connected to electromagnetic actuators. Low voltage operation (less than 50v) is provided without proportionally increased current, partly by energy recovery from the inductors in the actuators. Two levels of protection against supply ripple are included (RT, RLA) and the actuator drive can be stabilized against supply variation (MSC). The low-voltage operation provided is both safer and more efficient than mains voltage operation.
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