METHOD AND APPARATUS FOR OBTAINING DOSES FOR FORMING AN ANNULAR SEAL

An apparatus (1) and a method for obtaining doses (2) intended to form an annular seal (3; 30; 300) in a crown cap (4; 40; 400), the method comprising the steps of: - supplying a total flow of plastics to an exact N number of extrusion outlets (6) through as many supply channels (7) to obtain a partial flow of extruded plastics exiting from each extrusion outlet (6), each supply channel (7) being placed in flowing communication with a respective extrusion outlet (6); - providing for at least N-l adjustment members (10), each adjustment member (10) being operatively associated with a respective supply channel (7); - adjusting each partial flow exiting from each extrusion outlet (6), said adjusting each partial flow exiting from each extrusion outlet (6) comprising adjusting said at least N-l adjustment members (10); - moving a support element (17) that carries N dose separating elements (18) in an advancement direction (A) along a closed loop path so that each dose separating element (18) passes, at each revolution, in front of a respective extrusion outlet (6); during said moving and at each revolution of the support element (17), separating N doses (2) of plastics that are precursors of the annular seal (3; 30; 300), wherein each of the dose separating elements (18) separates a dose (2) of plastics from an extrusion outlet (6), said separating being provided after said adjusting each partial flow exiting from each extrusion outlet (6); - depositing the separate N doses (2) inside a crown cap (4; 40; 400); wherein the N number is equal to three or four or five. L'invention concerne un appareil (1) et un procédé d'obtention de doses (2) destinées à former un joint annulaire (3 ; 30 ; 300) dans une capsule (4 ; 40 ; 400), le procédé comprenant les étapes consistant à : - fournir un flux total de plastiques à un nombre N exact de sorties d'extrusion (6) à travers autant de canaux d'alimentation (7) pour obtenir un flux partiel de plastiques extrudées sortant de chaque sortie d'extrusion (6), chaque canal d'alimentation (7) étant placé en communication fluidique avec une sortie d'extrusion respective (6) ; - fournir au moins N-1 éléments d'ajustement (10), chaque élément d'ajustement (10) étant associé de manière fonctionnelle à un canal d'alimentation respectif (7) ; - ajuster chaque flux partiel sortant de chaque sortie d'extrusion (6), ledit ajustement de chaque flux partiel sortant de chaque sortie d'extrusion (6) comprenant l'ajustement desdits au moins N