Sewing machine with means for synchronizing drive of needle and loop taker motors

Abstract

A sewing machine including a head portion including a needle bar, the needle bar being for mounting a needle threaded with a needle thread; a principal shaft; a sewing machine motor for driving the needle bar via the principal shaft; a bed portion including a loop taker for taking a thread loop of the needle thread in cooperative operation with the needle; a loop taker drive shaft connected to move in association with the loop taker; a loop taker drive unit including a loop taker drive motor for driving the loop taker drive shaft independently of the principal shaft; a synchronization control unit for controlling at least one of the loop taker drive motor and the sewing machine drive motor so that the loop taker and the principal shaft rotate in synchronization; and an offset adjustment unit provided to the synchronization control unit and for adjusting an amount that the phase of the loop taker is offset from a reference phase offset amount preset for the loop taker with respect to the principal shaft.

Dependencies are inferred from the claim text.