Patent ID: 7135080
Filing Date: 2006-11-14
Classification: B29D

Abstract:
1. A method of winding a strip member on a drum of a tire building machine in a winding operation building a tire, comprising: providing a first strip end sensor directed at said drum at a first position along a path of rotational advance of a surface of said drum which is angularly displaced along said path of rotational advance from an angular position along said path of rotational advance whereat said strip member is brought into initial contact with said drum in order to detect a first detection position on said surface of said drum whereat said strip member is brought into initial contact with said drum; providing a second strip end sensor directed at a second position along said path of rotational advance of said surface of said drum which is angularly displaced from said first position along said path of rotational advance at which said first strip end sensor is directed; providing an angle detector to detect an angle of rotation of said drum; rotating said drum in a drum rotational direction while delivering a front end of said strip member to said drum to begin wrapping said strip member on said drum; detecting said front end of said strip member at said first detection position using said first strip end sensor and initiating a first angular measurement using said angle detector; detecting arrival of said front end of said strip member at said second strip end sensor; completing said first angular measurement using said angle detector and initiating a second angular measurement when said front end of said strip member is detected by said second strip end sensor and continuing to rotate said drum in said drum rotational direction; calculating a first angle representing angular displacement from said second strip end sensor to said first strip end sensor in the drum rotational direction based on output from said angle detector; detecting arrival of a trailing end of said strip member at said first strip end sensor brought about by rotating said drum in said drum rotational direction; completing said second angular measurement using said angle detector when said trailing end of said strip member is detected by said first strip end sensor to yield a second angle; and calculating an overlap length if said second angle is greater than said first angle and calculating a gap length if said second angle is less than said first angle.