There is provided a range switching device that can switch the shift ranges by use of a mechanical driving force source even when the motor does not normally function. The range switching device includes an output axle coupled with the shift shaft of an automatic transmission, a motor, an elastic driving device whose driving force source is elastic energy of an elastic member, and a coupling mechanism that couples the output axle, the motor, and the elastic driving device with one another; the elastic driving device has a holding mechanism in which there can be performed switching between a holding state where accumulated elastic energy is held and a releasing state where the elastic energy is released so as to drive the output axle.

An example rotary actuator includes a cam that is to be coupled to a valve. The cam is rotatable about an axis. The example rotary actuator also includes a linear actuator having a stem movable along a path offset from and perpendicular to the axis and a chain having a first end and a second end opposite the first end. The first end of the chain is coupled to the stem and the second end of the chain coupled to the cam. The chain is disposed around at least a portion of an outer edge of the cam, and movement of the stem along the path rotates the cam about the axis.

Aspects of the disclosure provide an electric actuator including a first driving source coupled to an output through a first pathway created by a transmission, a second driving source coupled to the output though a second pathway created by the transmission that, upon the electric actuator losses electrical power to the electric actuator, causes the output to be positioned at a fail-safe position, a differential coupled to the first driving source and the second driving source through a third pathway created by the transmission to store energy from the first driving source in the second driving source, and a switching controller that is configured to control switching the transmission between the first pathway, the second pathway, and the third pathway.

A linkage rod including a limited-displacement flexible mechanism has structural robustness and allows easy reduction in weight and size, simple production and easy operation. The linkage rod including at least one limited-displacement flexible mechanism, wherein the limited-displacement flexible mechanism comprises at least one limited-displacement flexible joint which comprises: a flexible member; and at least one bend limitation section which is arranged in parallel with the flexible member so that the bend limitation section limits a bend of the flexible member.