Yarn monitor, for weft yarns at a loom, has guides to lead the yarn through a deflected path with a converter to generate signals for yarn movement and tension from mechanical loading to an electronic evaluation unit

摘要

The yarn monitor (F), to detect whether the yarn is running or stopped and/or register the yarn tension, imposes a deflection in the yarn movement path where the yarn applies a mechanical force to a converter (W), with a piezo electric converter unit (20) integrated into a film chip which generates corresponding signals. At least one electronic evaluation unit (6) takes off the output signals (i1,i2). The yarn path is defined by yarn guides (8), upstream and downstream of the deflectors (D1,D2), where one registers the yarn movement and the other measures the yarn tension. Deflection surfaces (9,10) are aligned across the yarn axis, forming an included angle ( beta ) between them of = 180 in the direction of the yarn axis, dividing the deflection surfaces.