Abstract: A motor control device according to an embodiment includes a hardware processor configured to: calculate a first torsion torque generated by a motor shaft according to fluctuation of an engine torque based on a difference between a motor angle as a rotation angle of the motor shaft and a shaft angle as a rotation angle of a transmission shaft of a transmission on the downstream side of a damper; calculate a first vibration damping torque to be output by a motor generator to damp vibration of the motor shaft based on the first torsion torque and a drive state value indicating a drive state of an engine; and output a motor torque command value to be provided to the motor generator based on the first vibration damping torque.

Abstract: Rotary hook drive device for a sewing machine includes: a rotary hook rotatably provided on a rotary hook support; a cylindrical grooved cam provided on a drive shaft drivable to rotate in one direction; a cam follower engaged in a cam groove of the cylindrical grooved cam and capable of making reciprocative movement about a support shaft in response to rotation of the cylindrical grooved cam; and a transmission mechanism that transmits the reciprocative movement of the cam follower to the rotary hook to cause the rotary hook to make reciprocative pivoting movement. Such arrangements can prevent deviation in driving timing of the rotary hook and simplify the construction of the rotary hook drive device.

Abstract: Rotary hook drive device for a sewing machine includes: a rotary hook rotatably provided on a rotary hook support; a cylindrical grooved cam provided on a drive shaft drivable to rotate in one direction; a cam follower engaged in a cam groove of the cylindrical grooved cam and capable of making reciprocative movement about a support shaft in response to rotation of the cylindrical grooved cam; and a transmission mechanism that transmits the reciprocative movement of the cam follower to the rotary hook to cause the rotary hook to make reciprocative pivoting movement. Such arrangements can prevent deviation in driving timing of the rotary hook and simplify the construction of the rotary hook drive device.

Abstract: A thread cutter for a chain stitch sewing machine which performs chain stitch sewing by cooperation of a needle driven up and down and a looper arranged under a needle plate, including: a movable knife arranged so that it can advance into or retract from a gap between a top surface of the looper and an under surface of the needle plate; a knife driving mechanism for advancing and retracting the movable knife; a stationary knife arranged under the needle plate for cutting a sewing thread in cooperation with the movable knife when the movable knife is retracted; and a thread holding plate for holding a cut end of the sewing thread on the side of the looper in a predetermined position by a further retracting operation of the movable knife after the sewing thread is cut and a drive unit for a multi-sewing machine.

Abstract: In a chain stitch sewing machine which performs a required chain stitch sewing with respect to a cloth to be processed, by cooperation of a needle reciprocable up and down and a looper arranged under a needle plate, the chain stitch sewing machine comprises: (1) a large diameter drive gear rotatably provided in a base, (2) a looper support supported by the base so that it can slide in a lateral direction, (3) two or more loopers arranged on the looper support at intervals of a predetermined pitch along the lateral direction and freely rotatable on their own axes, (4) small diameter driven gears respectively provided in the two or more loopers and each engageable with the drive gear, and (5) a lock mechanism for non-rotatably locking the two or more loopers at a required timing.