Abstract PCT No. PCT/JP79/00043 Sec. 371 Date Oct. 21, 1980 Sec. 102(e) Date Oct. 21, 1980 PCT Filed Feb. 22, 1979 PCT Pub. No. WO80/01774 PCT Pub. Date Sep. 4, 1980.Arm having a gravity-balancing function effective for use in welding robots as well as robots employed in a variety of industrial fields. Projectively provided over the fulcrum of an arm (1) is a rotary sheave (2), whose position is perpendicularly maintained regardless of the vertical swaying of the arm (1). A wire (6) is extended from an action point (A) on a line traced by the center of gravity of the arm (1), to the rotary sheave (2), and is connected to a spring mechanism (3) which may extend by the length of elongation equal to the distance between the action point (A) and the rotary sheave (2), whereby a moment due to the weight of the arm (1) is completely balanced to provide an arm with gravity-balancing.
An arm assembly which functions to balance the weight of an arm by the action of a spring mechanism, wherein said arm assembly comprises: a rotary sheave vertically extending directly over the fulcrum of said arm with said rotary sheave being held in a vertical plane regardless of the vertically oscillating movement of said arm; and a wire extending from an action point on the center of gravity of said arm over said rotary sheave and is connected to said spring mechanism wherein said spring mechanism has a maximum expansion equal to the distance between the action point and said rotary sheave, thereby counterbalancing the moment produced by the weight of said arm.
Claim 2
Dependent Claim
113 words
An arm assembly which functions to balance the weight of an arm by the action of a spring mechanism, wherein said arm assembly comprises: a rotary sheave vertically extending directly over the fulcrum of said arm with said rotary sheave being held in a vertical plane regardless of the vertically oscillating movement of said arm; and a wire extending from an action point on the center of gravity of said arm over said rotary sheave and is connected to said spring mechanism wherein said spring mechanism has a maximum expansion equal to the distance between the action point and said rotary sheave, thereby counterbalancing the moment produced by the weight of said arm.
Claim 3
Dependent Claim
26 words
An arm assembly according to claim 1 wherein said spring mechanism includes a plurality of rotary sheaves fixed therein, a moving sheave and a spring member.