Picking controller for an air jet loom

A picking controller for an air jet loom having a main picking nozzle which jets air to pick a weft yarn into a shed, and groups of subnozzles which jet air to help the picked weft yarn run along a picking path, which comprises:

• a phase angle detector for detecting the phase angle of the air jet loom;
• a weft yarn arrival detector for detecting the arrival of the free end of the picked weft yarn at an arrival position;
• a memory for storing actual arrival phase angles of the picked weft yarns in relation to the phase angle of the air jet loom;
• a variation detector for determining arrival phase angle variations on the basis of the actual arrival phase angles detected in a predetermined period of time or in a predetermined number of picking cycles;
• a comparator which compares the phase angle variations with a predetermined target phase angle variation and provides a signal representing the result of comparison;
• a picking condition setting unit for sequentially varying a picking condition of the groups of subnozzles according to the signal representing the result of comparison given thereto from the comparator;
• a control unit which controls the picking condition of the groups of subnozzles according to a command given thereto from the picking condition setting unit;
• and
• an arithmetic unit which determines the correlation between picking condition and arrival phase angle on the basis of the actual arrival phase angle variations, and then determines a picking condition corresponding to the target arrival phase angle variation on the basis of the correlation between picking condition and arrival phase angle.