APPARATUS FOR MEASURING THE LENGTH OF WEFT YARN FOR A LOOM AND A LOOM INCLUDING SUCH APPARATUS

摘要

An apparatus for measuring the weft yarn length for a loom constructed in accordance with the present invention comprises at least two weft yarn supply units each having a weft yarn length measurement element presenting a yarn winding surface, an equal number of electric motors each adapted for winding weft yarn around said yarn winding surface of the measurement element, and weft yarn latching mechanisms for controlling the amount of the weft yarn wound on each winding surface and the transfer of the wound yarn in the weft inserting direction. Each of the rotational speeds of the respective motors and the operation of the respective weft yarn latching mechanisms may be controlled by a control unit in accordance with a preset weft yarn selection program. Each yarn length measurement element may be associated with a sensor for sensing the number of times the weft yarn is wound on the element. Sensor signals are introduced into the control means from said sensors and speed commands are outputted from said control means to respective motors for compensating for any fluctuations that may be caused in the measured lengths of the weft yarn.