ACTUATUNG MECHANISM WITH INTEGRAL BATTERY

The present invention describes a motor driven actuator device comprising an actuator motor; a control module; an input for receiving an external power supply; and a battery pack. The battery pack is electrically connected to selectively drive the actuator motor, and is electrically connectable to the external power supply for charging. During charging of the battery pack, the control module is configured to: receive data representative of the measured charge level of the battery pack; compare the measured charge level with a pre-determined charge level required to complete at least two battery shutdown events under battery power alone, wherein a battery shutdown event involves moving the actuator device to a failsafe position; and, if the measured charge level is equal to or greater than the pre-determined charge level, indicate the battery status to other internal components associated with the actuator device. During subsequent actuator device operation, the control module is configured to: detect and determine the validity of the external power supply, and if the external power supply is determined to be invalid, instruct a battery shutdown event causing the battery to be discharged, such that there will still be enough charge in the battery to complete at least one further battery shutdown event; and, subsequently detect when the external power supply becomes valid, and resume actuator device operation under the external power supply, whilst simultaneously recharging the battery pack to at least the pre-determined charge level.