A method of weft picking on a weaving machine and a picking device for carrying out the method

摘要

The invention relates to a method of weft (2) picking on a weaving machine comprising the shaping of the weft (2) to a U-shaped loop with two straight sections and a bend (20) situated transversely to the pick direction and to the directing of the weft (2) into pick means whereupon the weft (2) is set in motion in the pick direction and during its motion through the pick channel (30) one of its straight sections is stopped and the U-shaped loop weft (2) is continuously evolved due to the shortening of the other of its straight sections while the weft (2) in the shed (41) gets straighter and straighter until it is completely straight and its free end is situated outside the shed (41) whereupon the straightened weft (2) is beaten-up to the edge of the fabric being produced. The weft (2) adapted to a U-loop shape is acted upon by at least one stream of a picking medium oriented into the pick channel (30) and acting in particular on the bend (20) of the U-loop shaped weft (2) which is under this action carried through the pick channel (30) and carries with itself also the two straight sections of the U-loop shaped weft (2) as far as the stop of one of the straight sections of the U-loop shaped weft (2) whereupon the bend (20) of the U-loop shaped weft (2) shifts along the other, free straight section of the U-loop shaped weft (2) in the direction of (towards) the free end of the U-loop shaped weft (2), thus obtaining the increase in the weft (2) pick speed and improving the acceleration stage of the weft (2) pick.;The invention relates also to a picking device for carrying out the method on a jet loom comprising a chief picking jet (1) and related thereto a weft (2) metering member (6) with a weft supply (60) for the weft thread, the pick outlet (10) of the chief picking jet (1) being oriented in the pick direction. In parallel with the chief picking jet (1) there is arranged an auxiliary picking jet (7) with reversible operation and the picking device contains a reversing member (71) for the weft (2) whose weft (2) reversing channel (710) is adapted to be related with one of its ends to the pick outlet (10) of the chief picking jet (1), and with the other of its ends, to the suction inlet - pick outlet (70) of the auxiliary picking jet (7).