| 摘要 |
A process for building a tyre, comprising : - energizing a resonant circuit (31) of an electromagnetic sensor (30; 30'; 30"), in such a way that the resonant circuit (31) generates an electromagnetic field in a region comprising a head (23) of an extruder (20), - measuring a parameter (V) of the resonant circuit, produced in response to the energizing of the resonant circuit, this parameter being a function of the electrical permittivity characteristics of the region, - starting to extrude a continuous elongated element (21) made of elastomeric material through an aperture (24) formed in the head (23) of the extruder, in such a way that the electrical permittivity characteristics of the region are modified, - detecting a variation of the parameter (V) caused by the modification of the electrical permittivity characteristics, thus determining the presence of the continuous elongated element (21) outgoing from the aperture, - putting a forming drum (2) into rotation about its axis of rotation (X), at the end of a predetermined time interval after the detection of the variation of the parameter, - distributing the continuous elongated element (21) along a radially outer surface (3) of the forming drum (2), thereby forming at least a portion of a component of a tyre by winding on turns which are in side by side relationship and/or at least partially overlapping. An apparatus arranged to operate according to this process is also described. |
