Abstract: A one pick weft inserting, a defective weft determination method and method and a one pick weft inserting control system in a jet loom are provided wherein, in restarting the operation of the jet loom, one pick of weft is inserted and the weft is held securely to permit a smooth start-up of the jet loom. A weft length measuring device and a weft inserting nozzle are operated by a one pick command section provided in the control system to ensure one pick weft inserting into a warp shed, and after completion of the weft inserting operation, the warp shed is closed by a shed closing control section provided in the control system to hold the one pick weft securely, thereby preventing breaking, etc. of the weft.

Abstract: The present invention relates to a control system for an engagement pin employed in a drum-type weft storage unit which is mainly employed in a jet-loom for storing the weft and for measuring the same in length. A novel control system for an engagment pin employed in a drum-type weft storage unit is provided. An engagement-time is compensated on the basis of a difference in time between a target-time later than the engagement-time of the engagement pin by a normal time-lag, to make it possible that the engagement-time is always set to be optimum in spite of the existanece of variation in shuttling speed of the weft, so that it is possible to keep the variation in length of the delivered weft minimum while the weft feeler is employed in place of the disengagement sensor.

Abstract: A weft yarn feed device (1) comprises a measuring and storing drum (7) for storing a predetermined length of a weft yarn (4) thereon for picking operation, a rotary yarn guide (6) for winding the weft yarn (4) on the measuring and storing drum (7), a feed motor (8) for rotating the rotary yarn guide (6), a drive control unit (3) for controlling the operation of the feed motor (8), and a command control unit (2) which gives commands to the drive control unit (3). The length of the weft yarn (4) wound on the measuring and storing drum (7) is detected accurately on the basis of the relation between the number of rotation of the rotary yarn guide (6) and that of the crankshaft of the loom, and a detection signal indicating the length of the weft yarn (4) wound on the measuring and storing drum (7) is fed back to the command control unit (2) to control the feed motor ( 8) properly for winding a predetermined length of the weft yarn (4) on the measuring and storing drum.