Variably controllable bobbin thread pull-off mechanism

摘要

A variable pull-off mechanism for a sewing machine is provided with a thread pull-off disc on a rotatably mounted shaft which is concentric with the drive shaft of a vertical axis looptaker. The disc is formed with thread catching edges which engage and pull-off thread from a bobbin as the disc is oscillated between a fixed and a controllable position in accordance with the operation of a servomotor responsive to various control signals.