Abstract: A two-needle overlock sewing machine comprises a throat plate and a middle tongue. The throat plate has an opening needle hole and an outer tongue. The middle tongue is disposed parallel to the outer tongue, a thread chain is formed so as to envelop both tongues. The presser foot is disposed so as to press the cloth to the throat plate by a spring. A push-up lever lifts up the presser foot by handling. The push-up lever and the middle tongue are coupled together by a transmission mechanism. By raising the presser foot by manipulation of the push-up lever at the finish of sewing operation, the middle tongue draws back simultaneously and retreats from the needle hole. As a result, the manipulation for drawing back the middle tongue during the process of thread chain handling is not needed, and the operation is simplified.

Abstract: A two-needle overlock sewing machine comprises a throat plate and a middle tongue. The throat plate has an opening needle hole and an outer tongue. The middle tongue is disposed parallel to the outer tongue, a thread chain is formed so as to envelop both tongues. The presser foot is disposed so as to press the cloth to the throat plate by a spring. A push-up lever lifts up the presser foot by handling. The push-up lever and the middle tongue are coupled together by a transmission mechanism. By raising the presser foot by manipulation of the push-up lever at the finish of sewing operation, the middle tongue draws back simultaneously and retreats from the needle hole. As a result, the manipulation for drawing back the middle tongue during the process of thread chain handling is not needed, and the operation is simplified.

Abstract: A thread cutter for an interlock sewing machine wherein the sewing machine has a small diameter cylindrical arm and the cloth being sewn is fed along the axis of the arm. A plurality of needles are disposed along a line orthogonal to the axis of the arm and an arcuated, movable member having a hook at its tip is pivotably supported ahead of feed dogs on the sewing machine relative to the line of feed. The arcuated, movable member is turned by means of an operative plate disposed along the axis of the arm and, in cooperation with a fixed blade, cuts threads after the cloth has been sewn.