Abstract: A device for monitoring the tension on a thread comprises a frame for retaining the thread; a leaf spring on the frame for bearing against the thread and being displaced thereby as a function of such tension; a generator, such as a permanent magnet on the leaf spring, for generating an electromagnetic field between the frame and the leaf spring which varies as a function of such displacement; a Hall effect sensor which senses such field and generates an output signal indicative of such tension; and an electronic system for receiving said output signal and indicating whether said output signal and thereby said thread tension is within a predetermined desirable range. The indication is made at least at a location in the vicinity of the frame where it can be seen by persons who are responsible for maintaining the correct thread tension, and may comprise a plurality of LEDs for indicating respectively when the thread tension is too high, too low, and at the correct level.

Abstract: The jacket enclosing a motor driven textile spindle of the type wherein the spindle is driven by a separate motor which is mounted on a common base with the spindle is modified to include air inlet and air exit openings. The motor is located in proximity to the spindle and is coupled to it by a toothed belt or the like. As the spindle is rotated by the motor air is drawn in through the inlet opening of the spindle and exits through the exit openings in the form of a strong stream of air which blows on and cools the motor. In this manner the spindle doubles as a fan for the motor and the necessity of providing a separate fan for the motor is avoided, resulting in savings in space and energy for driving a fan.

Abstract: A device for measuring the tensile force on a thread includes a housing having thread guides at the points of inlet and outlet of the thread. A spring plate is mounted on the housing intermediate the thread guides and has a dumbbell-shaped guide member at its end for engaging the thread. The spring plate is so mounted that the tension on the thread displaces the spring plate from its initial unflexed position. Adjacent the guide member on the movable spring plate is a permanent magnet which moves with the spring plate as it displaces. A sensor employing the Hall effect is fixed to the housing at a given distance from the magnet. Movements by the magnet are detected by the Hall sensor, which produces an output signal indicative of the displacement of the spring plate, which signal is processed to give an indication of the thread tension.