UN DISPOSITIVO PARA SINCRONIZAR EL AFLOJAMIENTO DE LA TEN- SION DEL HILO DE LA AGUJA CON LA OPERACION DE CORTE, CON TEMPORIZACION DEL AFLOJAMIENTO DE LA TENSION DEL HILO, EN MAQUINAS DE COSER.

摘要

A device is disclosed for synchronizing the slackening of the needle-thread tension with the cutting of the thread in a sewing machine, especially a sewing machine of the overcast stitch type. The device comprises a pneumatic assembly controlled by magnetic valves and a characteristic pneumatic delay mechanism is provided in order to provide an exceptionally accurate adjustment of the time during which the discs of the thread-tensioning device are kept open. The whole assembly is constructionally simple and cheap and is fully reliable in service.