Abstract: A device for automatic tension release in an upper thread tension adjusting assembly which includes a drive shaft, actuating the detachment of the tension disks of said adjusting device, characterized in that said drive member is built in the thread tension adjusting device and is made by an electromagnet placed in a circular crown arranged between the tension disks and the adjusting knob.

Abstract: An automatic sewing unit formed by a loading station, a mounting table, a transfer mechanism, two preparing stations, two sewing stations and a stacking station for sewn pieces in which the transfer mechanism is made from a mounting member sliding on a guide driven by a pneumatic motor and whereon are positioned a first group of kinematic members and their relative pneumatic actuators to obtain the lifting and lowering movements of a series of pressers provided for the intermittent conveyance of the fabric pieces to be sewn and a second group of kinematic members and their relative pneumatic actuators to vertically draw displacement of the fabric piece from a stack placed in the loading station. Progressive movement of the fabric pieces toward the following stations are made by the displacement of the mounting member along the guide.

Abstract: A sewing threads trimming device for sewing machines provided with a blade adapted to make, at the end of a sewing operation and in a suitable timing relation with the hook and needle movements, a first displacement over the hook during which a thread loop closes over the blade and thereafter a second movement in the opposite direction to bring the sewing threads into contact with a counterblade and cut them, including a cam of magnetizable material deriving its motion from the sewing machine main shaft and having a portion of little thickness and an arc-shaped front contour and a second portion diametrically opposed to the first having a particular contour to impart prescribed motion to the threads trimming blade and a cam follower comprised of a U-shaped member closed by a cylindrical portion adapted to couple with the cam and connected to a blade carrying shaft through a plate and crank mechanism.