Extendable arm and structure using the same

摘要

An extendable arm (30) is formed by a plurality of cross units (31) arranged in one direction and pivotally coupled to each other, and each of the cross units is formed by two rigid members (31a, 31b) that are pivotally coupled at a central coupling point (c) so as to cross over each other to form an X-shape. In order for the extendable arm (30) to follow a curved-line path when being extended and contracted, each of the rigid members (31a, 31b) has such a curved shape that coupling points (d, e) at both ends of the rigid member are shifted toward one side from a longitudinal axis passing through the central coupling point (c).

主权项

1. An extendable arm comprising:
a plurality of cross units arranged in one direction and pivotally coupled to each other, each of said cross units comprising two rigid members that are pivotally coupled at a central coupling point so as to cross over each other to form an X-shape, wherein in order for said extendable arm to follow a curved-line path when being extended and contracted, each of said rigid members has such a curved shape that coupling points at both ends of said rigid member are shifted toward one side from a longitudinal axis passing through said central coupling point, and said rigid member has a linear shape in its central region in a longitudinal direction of said rigid member.