Opening-and-closing device and robot device

摘要

One embodiment of the invention provides an opening-and-closing unit which can open and close with respect to a base unit. When the opening-and-closing unit is pushed toward the base unit as if making them close such that the facing surfaces of the rotational body pinching units cover the outer surfaces of the rotational body to attach the opening-and-closing unit to the rotational body, the shaft end sections and the angle reference sections fit in the shaft supporting sections and the angle adjustment sections respectively, and thereby hold the rotational body so as to align the rotational range with the opening-and-closing range.