Patent ID: 6070619
Filing Date: 2000-06-06
Classification: D03D

Abstract:
A method of controlling an easing roller of a loom, wherein the loom comprises the easing roller, a warp beam, and a servomotor for moving the easing roller in forward and backward directions, wherein satin stripe warp yarns are wound around the warp beam and wound around the easing roller, and ground warp yarns are wound around the warp beam and wound around a roller separate from the easing roller, said method comprising:driving the servomotor during a position control period of a weaving cycle to move the easing roller forward to a predetermined position so as to provide the satin stripe warp yarns with a predetermined first tension, wherein the position control period includes a beating-up moment;driving the servomotor during a tension control period of the weaving cycle to move the easing roller backward so as to provide the satin stripe warp yarns with a predetermined second tension greater than the first tension, wherein the tension control period includes a maximum shed formation moment; andcontrolling said driving of the servomotor during a position control period and said driving of the servomotor during a tension control period, said controlling comprising:(A) measuring periodically an actual position of the easing roller;(B) determining a correction distance based on a difference between a desired easing roller position and the actual position; and(C) correcting a controlled variable based upon the correction distance, wherein the corrected controlled variable is used to control at least one of said driving of the servomotor during a position control period and said driving of the servomotor during a tension control period to move the easing roller such that the actual position of the easing roller at least approaches the desired easing roller position.