Electric actuator and module for supplying power during a power failure

An electric actuator system, comprising:

• an electric actuator, wherein the electric actuator comprises a rotatable shaft responsive to a first signal that is generated based at least in part on a second signal received from outside the electric actuator, the first signal being generated based at least in part on the desired position for the rotatable shaft indicated by the second signal;
• and
• a module detachably connected to the electric actuator, wherein the module comprises:
• a detection circuit generating a third signal;
• a power supply storing primary power supplied to the electric actuator, the power supply providing secondary power of a similar type as the primary power;
• a first switching circuit outputting, in response to the third signal, one of the second signal or a fourth signal;
• and
• a second switching circuit outputting, in response to the third signal, one of the primary power or the secondary power.

A method for providing an electric actuator with a shutoff function, the method comprising the steps of:

• detecting whether primary power is available to the electric actuator, the detecting step being performed external to the electric actuator;
• providing primary power to the electric actuator when the detecting step indicates that primary power is available to the electric actuator;
• switching to secondary power when the detecting step indicates that primary power is not available to the electric actuator;
• providing a first signal that specifies an output condition for the electric actuator in response to the detecting step indicating that primary power is available to the electric actuator;
• and
• switching to a second signal that specifies another output condition for the electric actuator in response to the detecting step indicating that primary power is not available to the electric actuator.

A method for providing an electric actuator with a shutoff function, the method comprising the steps of:

• generating first and second signals external to the actuator;
• switching between the first and second signals to select one of the first and second signals to supply to the electric actuator;
• and
• generating a third signal internal to the electric actuator based at least in part on the selected one of the first and second signals.