Patent ID: 8096251

Claim:
A multi-head sewing machine comprising: a plurality of sewing heads, each of the sewing heads having a needle bar caused to move up and down for carrying out a sewing operation, each of the plurality of sewing heads including: a needle bar drive source provided independently of each of the sewing heads; a crank mechanism for converting rotary drive of the needle bar drive source to up-and-down motion of the needle bar; and a balancer fixedly attached to a rotary input shaft of the crank mechanism, the balancer rotating at substantially an opposite phase with respect to the up-and-down motion of the needle bar in order to reduce vibration generated due to the up-and-down motion of the needle bar; and a control device for controlling each pair sewing heads that are paired with each other by arbitrarily combining the plurality of sewing heads so that each pair of sewing heads is rotationally driven to cause rotational directions of the needle bar drive sources thereof to become opposite directions to each other.