Plant for Manufacturing Tyres and Manufacturing Method Related Thereto

Abstract

Within tyre manufacturing, a reinforcing structure of the tyre, such as a zero-degree layer of the belt structure, is made by an apparatus including devices for guiding a continuous elongated element toward a forming drum; devices for applying the elongated element against a laying surface of the drum; and a cutting unit to cut off the continuous elongated element when application has been completed. Once the cutting operation has been carried out, the free end of the continuous elongated element is set to a grip position downstream of the cutting unit through a reciprocating slider and a threading element blocking the continuous elongated element with respect to the slider when the latter moves toward the forming drum.

1 - 52 . (canceled) 
     
     
         53 . A plant for manufacturing tyres, comprising:
 devices to make a carcass structure;   devices to make a belt structure; and   devices to apply the belt structure to the carcass structure at a radially external position thereof,   
       wherein the devices to make the belt structure comprise at least one apparatus for forming a reinforcing structure, comprising:
 a forming drum drivable in rotation; 
 devices to guide a continuous elongated element comprising at least one reinforcing cord toward the forming drum; 
 devices for application of the continuous elongated element against a laying surface externally carried by the forming drum; 
 at least one unit for cutting the continuous elongated element on a length thereof between the guide devices and the application devices; and 
 feeding devices operating on the continuous elongated element to set one free end of the continuous elongated element to a grip position downstream of the cutting unit, 
 
       wherein the feeding devices comprise a slider movable with a reciprocating motion in a longitudinal feed direction of the continuous elongated element and at least one threading element carried by the slider and operating on the continuous elongated element to block it with respect to the slider when the slider moves toward the forming drum. 
     
     
         54 . The plant as claimed in  claim 53 , wherein the cutting unit is operatively mounted on said slider. 
     
     
         55 . The plant as claimed in  claim 53 , wherein the cutting unit comprises a first cutting edge and a second cutting edge that are mutually movable toward a cutting position and before reaching the cutting position, define a passage clearance enclosing the continuous elongated element at least partly. 
     
     
         56 . The plant as claimed in  claim 55 , wherein the passage clearance is defined by an opening formed in the second cutting edge. 
     
     
         57 . The plant as claimed in  claim 55 , wherein the first cutting edge is movable upon command of a linear actuator operating on the first cutting edge through an inclined plane. 
     
     
         58 . The plant as claimed in  claim 57 , wherein the inclined plane is carried by a thrust block connected to the linear actuator and co-operating with an abutment connected to the first cutting edge of the cutting unit. 
     
     
         59 . The plant as claimed in  claim 58 , wherein the thrust block has a return extension carrying an auxiliary inclined plane operating on the abutment on the opposite side from said inclined plane, to bring the first cutting edge back to a rest position. 
     
     
         60 . The plant as claimed in  claim 53 , wherein the feeding devices operate on the continuous elongated element upstream of the cutting unit to cause longitudinal translation of the continuous elongated element to the grip position. 
     
     
         61 . The plant as claimed in  claim 53 , wherein said threading element slides relative to the continuous elongated element during movement of the slider away from the forming drum. 
     
     
         62 . The plant as claimed in  claim 53 , wherein said threading element has one free end acting against the continuous elongated element at a contact point aligned with an oscillation axis of the threading element in a direction that, with the longitudinal feed direction of the continuous elongated element, forms an acute angle facing the cutting unit. 
     
     
         63 . The plant as claimed in  claim 53 , further comprising return-preventing devices operating on the continuous elongated element upstream of the cutting unit to hinder sliding of the continuous elongated element away from the cutting unit. 
     
     
         64 . The plant as claimed in  claim 63 , wherein said return-preventing devices comprise at least one auxiliary grip element having one free end acting against the continuous elongated element at a contact point aligned with an oscillation axis of the auxiliary grip element in a direction that, with the longitudinal feed direction of the continuous elongated element, forms an acute angle facing the cutting unit. 
     
     
         65 . The plant as claimed in  claim 60 , further comprising at least one guide duct longitudinally passed through by the continuous elongated element to hinder side deflections of the continuous elongated element on a length thereof upstream of the cutting unit. 
     
     
         66 . The plant as claimed in  claim 65 , wherein the guide duct comprises a movable section fixed with respect to the slider and a fixed section integral with the cutting unit and telescopically in engagement with the movable section. 
     
     
         67 . The plant as claimed in  claim 53 , wherein the application devices comprise at least one presser roller operatively carried by an arm oscillating between a rest position at which the presser roller is spaced apart from the forming drum and a work position at which the presser roller operates in thrust relationship on the continuous elongated element to urge it against the laying surface of the forming drum. 
     
     
         68 . The plant as claimed in  claim 53 , wherein said guide devices, application devices and cutting unit are carried by a carriage that is movable in parallel to a geometric axis of the forming drum to distribute the continuous elongated element into coils disposed in side by side relationship on the laying surface of the forming drum driven in rotation. 
     
     
         69 . The plant as claimed in  claim 68 , comprising at least two of said carriages carrying respective guide devices, application devices and cutting units, said carriages being movable symmetrically with respect to an equatorial plane of the forming drum to simultaneously form two portions of said reinforcing structure that are disposed symmetric to the equatorial plane. 
     
     
         70 . An apparatus for making reinforcing structures for tyres, comprising:
 a forming drum drivable in rotation;   devices to guide a continuous elongated element comprising at least one reinforcing cord, toward the forming drum;   devices for application of the continuous elongated element against a laying surface externally carried by the forming drum; and   feeding devices operating on the continuous elongated element to arrange one free end of the continuous elongated element to a grip position downstream of the cutting unit,   
       wherein the feeding devices comprise a slider movable with a reciprocating motion in a longitudinal feed direction of the continuous elongated element, and at least one threading element carried by the slider and operating on the continuous elongated element to block it with respect to the slider when the latter moves toward the forming drum. 
     
     
         71 . The apparatus as claimed in  claim 70 , wherein the cutting unit is operatively mounted on said slider. 
     
     
         72 . The apparatus as claimed in  claim 70 , wherein the cutting unit comprises a first cutting edge and a second cutting edge that are mutually movable to a cutting position and before reaching the cutting position, define a passage clearance enclosing the continuous elongated element at least partly. 
     
     
         73 . The apparatus as claimed in  claim 70 , wherein said threading element slides with respect to the continuous elongated element during movement of the slider away from the forming drum. 
     
     
         74 . The apparatus as claimed in  claim 70 , further comprising return-preventing devices operating on the continuous elongated element upstream of the cutting unit to hinder sliding movements of the continuous elongated element away from the cutting unit. 
     
     
         75 . The apparatus as claimed in  claim 73 , further comprising at least one guide duct longitudinally passed through by the continuous elongated element to hinder slide deflections of the continuous elongated element on a length thereof upstream of the cutting unit. 
     
     
         76 . The apparatus as claimed in  claim 70 , wherein said guide devices, application devices and cutting unit are carried by a carriage that is movable in parallel to a geometric axis of the forming drum to distribute the continuous elongated element into coils disposed mutually in side by side relationship on the laying surface of the forming drum driven in rotation. 
     
     
         77 . The apparatus as claimed in  claim 76 , comprising at least two of said carriages carrying respective guide devices, application devices and cutting units, said carriages being symmetrically movable with respect to an equatorial plane of the forming drum to simultaneously form two portions of said reinforcing structure disposed symmetric to the equatorial plane. 
     
     
         78 . A method of manufacturing tyres, comprising the steps of:
 making a carcass structure;   making a belt structure; and   applying the belt structure to the carcass structure at a radially external position thereof,   
       wherein the step of making the belt structure comprises formation of at least one reinforcing structure through winding on the forming drum of at least one continuous elongated element comprising at least one reinforcing cord, to form circumferential coils disposed consecutively in side by side relationship, wherein winding comprises the following steps:
 guiding the continuous elongated element toward the forming drum drivable in rotation; 
 applying the continuous elongated element against a laying surface externally carried by the forming drum; 
 cutting the continuous elongated element upon the action of a cutting unit; and 
 setting one free end of the continuous elongated element to a grip position downstream of the cutting unit, 
 
       wherein the step of setting one free end of the continuous elongated element to a grip position comprises the steps of driving a slider movable with a reciprocating motion in a longitudinal feed direction of the continuous elongated element and blocking the continuous elongated element with respect to the slider when the latter moves toward the forming drum. 
     
     
         79 . The method as claimed in  claim 78 , wherein the cutting unit is operatively mounted on said slider and carries out a translation together with said slider. 
     
     
         80 . The method as claimed in  claim 78 , wherein, in the cutting unit, a first cutting edge and a second cutting edge carry out a mutual movement toward a cutting position, said first and second cutting edges before reaching the cutting position, defining a passage clearance enclosing the continuous elongated element at least partly. 
     
     
         81 . The method as claimed in  claim 80 , wherein the passage clearance is defined by an opening arranged in the second cutting edge. 
     
     
         82 . The method as claimed in  claim 80 , wherein the cutting step is carried out by translation of the first cutting edge upon command of a linear actuator operating on the first cutting edge through an inclined plane. 
     
     
         83 . The method as claimed in  claim 82 , wherein the inclined plane is arranged on a thrust block connected to the linear actuator and co-operating with an abutment connected to the first cutting edge of the cutting unit. 
     
     
         84 . The method as claimed in  claim 83 , wherein the cutting operation further comprises the step of bringing the first cutting edge back to the rest position through an auxiliary inclined plane arranged in a return extension carried by the thrust block and operating on the abutment on the opposite side from said inclined plane. 
     
     
         85 . The method as claimed in  claim 78 , wherein the step of arranging one free end of the continuous elongated element to a grip position further comprises the step of longitudinally translating the slider relative to the continuous elongated element when the slider moves away from the forming drum. 
     
     
         86 . The method as claimed in  claim 78 , wherein the continuous elongated element is caused to translate to the grip position by a step-by-step movement. 
     
     
         87 . The method as claimed in  claim 78 , wherein blocking of the continuous elongated element with respect to the slider is carried out by a threading element having one free end acting against the continuous elongated element at a contact point aligned with an oscillation axis of the threading element in a direction that, with the longitudinal feed direction of the continuous elongated element, forms an acute angle facing the cutting unit. 
     
     
         88 . The method as claimed in  claim 78 , further comprising the step of hindering sliding movements of the continuous elongated element away from the cutting unit. 
     
     
         89 . The method as claimed in  claim 78 , wherein sliding of the continuous elongated element away from the cutting unit is hindered by an auxiliary grip element having one free end acting against the continuous elongated element at a contact point aligned with an oscillation axis of the auxiliary grip element in a direction that, with the longitudinal feed direction of the continuous elongated element, forms an acute angle facing the cutting unit. 
     
     
         90 . The method as claimed in  claim 78 , further comprising the step of hindering side deflections of the continuous elongated element at least on a length thereof upstream of the cutting unit. 
     
     
         91 . The method as claimed in  claim 78 , wherein side deflections of the continuous elongated element, at least on a length thereof upstream of the cutting unit, are hindered by guiding the continuous elongated element along at least one guide duct longitudinally passed through by the elongated element itself. 
     
     
         92 . The method as claimed in  claim 91 , wherein the guide duct comprises a movable section that is fixed relative to the slider and a fixed section telescopically in engagement with the movable section, mutual sliding movements between the fixed section and movable section being carried out concurrently with the step-by-step movement of the continuous elongated element. 
     
     
         93 . The method as claimed in  claim 78 , wherein application of the continuous elongated element is carried out by urging the continuous elongated element against the laying surface of the forming drum by means of a presser roller. 
     
     
         94 . The method as claimed in  claim 78 , further comprising the step of simultaneously translating said guide devices, application devices and cutting unit in parallel to a geometric axis of the forming drum to distribute the continuous elongated element into coils disposed in mutual side by side relationship on the laying surface of the forming drum driven in rotation. 
     
     
         95 . The method as claimed in  claim 78 , wherein at least two continuous elongated elements are simultaneously laid on the forming drum to form two portions of said reinforcing structure symmetrically disposed relative to the equatorial plane. 
     
     
         96 . A method of making a reinforcing structure for tyres, comprising the steps of winding at least one continuous elongated element comprising at least one reinforcing cord on a forming drum to form circumferential coils disposed consecutively in side by side relationship, wherein winding takes place by the steps of:
 guiding the continuous elongated element toward the forming drum drivable in rotation;   applying the continuous elongated element against a laying surface externally carried by the forming drum;   cutting off the continuous elongated element upon the action of a cutting unit; and   setting one free end of the continuous elongated element to a grip position downstream of the cutting unit,   
       wherein the step of setting one free end of the continuous elongated element to a grip position comprises the steps of driving a slider movable with a reciprocating motion in a longitudinal feed direction of the continuous elongated element and blocking the continuous elongated element with respect to the slider when the latter moves toward the forming drum. 
     
     
         97 . The method as claimed in  claim 96 , wherein the cutting unit is operatively mounted on said slider and carries out a translation together with the latter. 
     
     
         98 . The method as claimed in  claim 96 , wherein in the cutting unit a first cutting edge and a second cutting edge carry out a mutual movement toward a cutting position, said first and second cutting edges before reaching the cutting position defining a passage clearance enclosing the continuous elongated element at least partly. 
     
     
         99 . The method as claimed in  claim 96 , wherein the step of setting one free end of the continuous elongated element to a grip position further comprises the step of carrying out a longitudinal translation of the slider with respect to the continuous elongated element when the slider moves away from the forming drum. 
     
     
         100 . The method as claimed in  claim 96 , wherein the continuous elongated element is caused to translate to the grip position by a step-by-step movement. 
     
     
         101 . The method as claimed in  claim 96 , further comprising the step of hindering sliding movements of the continuous elongated element away from the cutting unit. 
     
     
         102 . The method as claimed in  claim 96 , further comprising the step of hindering side deflections of the continuous elongated element at least on a length thereof upstream of the cutting unit. 
     
     
         103 . The method as claimed in  claim 96 , further comprising the step of simultaneously translating guide devices, application devices and cutting units in parallel to a geometric axis of the forming drum, to distribute the continuous elongated element into coils disposed in mutual side by side relationship on the laying surface of the forming drum driven in rotation. 
     
     
         104 . The method as claimed in  claim 96  wherein at least two continuous elongated elements are simultaneously laid on the forming drum to form two portions of said reinforcing structure disposed symmetric to the equatorial plane.