The Beating-up Motion PDF

Textile Institute of Pakistan, Karachi. TEXT312 (Weaving Mechanisms) The Beating-up Motion Beating-up is the third and the final primary motion of the loom. The process of pushing the newly inserted weft yarn into the fell of the cloth is called as beatin...

Textile Institute of Pakistan, Karachi. TEXT312 (Weaving Mechanisms) The Beating-up Motion Beating-up is the third and the final primary motion of the loom. The process of pushing the newly inserted weft yarn into the fell of the cloth is called as beating-up or beating-in. The fell of the cloth is the line that divides the warp yarns and the cloth. The beating-up motion is performed by a loom accessory called as the reed. Reed is a wooden, plastic or metallic frame having vertically held metallic wires placed at a fixed pre-determined distance. Reeds are specified by their reed number or count indicating number of dents present in the reed per unit length. The Reed Beating-up on Shuttle Looms Prepared By: Shakeel Ahmad Paracha Page 1 of 5  Textile Institute of Pakistan, Karachi. TEXT312 (Weaving Mechanisms) Prepared By: Shakeel Ahmad Paracha Page 2 of 5  Textile Institute of Pakistan, Karachi. TEXT312 (Weaving Mechanisms) The beating up mechanism is connected with crank shaft. Here, crank shaft is connected with machine pulley. The crank shaft contains crank. Each crank connected with crank arm by crank pin and it contain bearing for smooth operation. Crank arm and sley sword are attached with sword pin. Position of the reed is top of the sley race board. Reed cap placed on the top of the reed. The whole parts of the beating up mechanism are mounted on rocking shaft. Crank shaft achieved motion from machine pulley. When crank shaft rotate due to the structure of the crank it moves forward and backward. Each crank connected with crank arm which is connected with reed. So, when crank shaft rotates reed move forward and backward for beat-up. (1) (2) (3) (4) Prepared By: Shakeel Ahmad Paracha Page 3 of 5  Textile Institute of Pakistan, Karachi. TEXT312 (Weaving Mechanisms) (5) Eccentricity The motion of the sley and the reed deviates from the simple harmonic motion (SHM) because of the cranks. This deviation from the SHM is called as eccentricity which is found out as: Eccentricity = e = Crank radius / Crank arm length Because of eccentricity, the sley moves faster when it approaches the front position to beat-up and moves slower as it reaches the back position where picking is done. The value of eccentricity ranges from 0.25 to 0.40. Greater the value of (e) greater will be the eccentricity and so as the force of beat-up. Beating-up on Shuttle-less Looms Prepared By: Shakeel Ahmad Paracha Page 4 of 5  Textile Institute of Pakistan, Karachi. TEXT312 (Weaving Mechanisms) (1) (2) (3) (4) Forces Acting on Yarns in Beat-Up Prepared By: Shakeel Ahmad Paracha Page 5 of 5