Balancer mechanism for rotating shaft

Abstract

To provide a balancer mechanism where a balancing rotary moment, which offsets at least a part of a rotary moment operating on a rotary shaft, operates on the rotary shaft by a gas spring to reduce the rotary moment simply and reliably. The balancer mechanism for rotary shaft (8) is provided with a cam member (10) fixed to the left end of rotary shaft (3), a cam follow-up member (15) which makes contact with the cam member (10) to follow it up, and a gas spring (20) comprising a gas spring (20) elastically energizing the cam follow-up member (15) toward the cam member (10) and operates a balancing rotary moment offsetting at least a part of the rotary moment of rotary shaft on the rotary shaft (3) via the cam follow-up member (16) and the cam member (10).

Dependencies are inferred from the claim text.