SPRING-ASSISTED ROTARY ACTUATOR
The present disclosure may be embodied as a rotary actuator for lifting a load against gravity. The actuator includes a housing and a drive motor attached to the housing. The drive motor has a drive shaft. The driveshaft may be configured to be manually operated. A rotatable output shaft is attached to the housing and in mechanical communication with drive shaft. The actuator includes at least one spring which is configured to act on the output shaft to at least partially offset a weight of the load. The at least one spring may be a torsion spring. The at least one spring may be configured to unwind when the motor is driven to lift the load, and may be configured to be wound when the motor is driven to lower the load. The at least one spring may comprise a plurality of springs, such as torsion springs.