초록 ▼

An expandable and contractable arm is constituted by a plurality of expandable and contractable units and connecting devices including universal joints for serially interconnecting the units into the arm. Each unit includes at least three expandable and contractable operating members in the form of

An expandable and contractable arm is constituted by a plurality of expandable and contractable units and connecting devices including universal joints for serially interconnecting the units into the arm. Each unit includes at least three expandable and contractable operating members in the form of link mechanisms or double thread type expandable and contractable rods, and actuating devices for equally or unequally expanding and contracting the operating members so as to increase or decrease distances between the connecting members while maintaining them in parallel or inclined with respect to each other.

대표청구항 ▼

An expandable and contractable arm comprising: a plurality of independently expandable and contractable units; and connecting means including universal joints for serially interconnecting said units into said arm; each of said units comprising a pair of disc members disposed at opposite ends of said

An expandable and contractable arm comprising: a plurality of independently expandable and contractable units; and connecting means including universal joints for serially interconnecting said units into said arm; each of said units comprising a pair of disc members disposed at opposite ends of said unit, at least three link mechanisms each comprising two links, the inner ends of said links being connected together by a pin and the outer ends of said links being connected to said pair of disc members through said universal joints and means for relatively rotating said two links about said pin independently from the other said link mechanisms within said unit thereby expanding and contracting each unit independently from another unit when said at least three link mechanisms are operated equally, and bending each unit independently from another unit when said at least three link mechanisms are operated unequally.