Extruder system for extruding cord reinforced extrudate

Abstract

The invention relates to an extruder system and a method for extruding cord reinforced extrudate, wherein the extruder system comprises an extruder head with a die for receiving extrusion material and a cord guide for guiding cords in a common cord plane in a cord direction into the die, wherein the extruder system comprises a first extruder and a second extruder, wherein the extruder head comprises a first flow channel and a second flow channel, wherein the extruder system further comprises a first pump and a second pump for receiving the extrusion material from the first extruder and the second extruder and for directing said extrusion material into the first flow channel and the second flow channel.

1 . An extruder system for extruding cord reinforced extrudate, wherein the extruder system comprises:
 an extruder head with a die for receiving extrusion material and a cord guide for guiding cords side by side in a common cord plane in a cord direction into the die so that, in use, the cords are embedded in the extrusion material in the die;   wherein the extruder system comprises a first extruder and a second extruder external to the extruder head, wherein the extruder head comprises a first flow channel that debouches into the die from a first side of the cord plane and a second flow channel that debouches into the die from a second side of the cord plane opposite to the first side;   wherein the extruder system further comprises a first pump between the first extruder and the first flow channel and a second pump between the second extruder and the second flow channel, wherein the first pump and the second pump are arranged for receiving the extrusion material from the first extruder and the second extruder and for directing said extrusion material into the first flow channel and the second flow channel, respectively;   wherein the extruder system is provided with a first pressure sensor and a second pressure sensor at or near the output side of the first pump and the second pump, respectively, and upstream of or at the entrance of the first flow channel and the second flow channel, respectively, for measuring the pressures of the flows of extrusion material flowing from the first pump and the second pump into the first flow channel and the second flow channel, wherein the extruder system further comprises a control unit that is operationally connected to the first pump and the second pump and the first pressure sensor and the second pressure sensor for controlling the speeds of the first pump and the second pump based on the measurements from the first pressure sensor and the second pressure sensor.   
     
     
         2 . The extruder system according to  claim 1 , wherein the extruder head has a feeding plane that extends orthogonal to the cord plane and parallel to the cord direction, wherein the first extruder and the second extruder are arranged for supplying the extrusion material in a first supply direction and a second supply direction, respectively, wherein the first supply direction and the second supply direction are oblique with respect to the feeding plane, wherein the first pump and the second pump are arranged for receiving the extrusion material from the first extruder and the second extruder in the first supply direction and the second supply direction, respectively, and for directing said extrusion material in or parallel to the feeding plane into the first flow channel and the second flow channel, respectively. 
     
     
         3 . The extruder system according to  claim 2 , wherein the first supply direction and the second supply direction are each offset with respect to the feeding plane over an angle of at least fifteen degrees. 
     
     
         4 . The extruder system according to  claim 2 , wherein the first supply direction and the second supply direction are offset with respect to the cord direction in the same direction. 
     
     
         5 . The extruder system according to  claim 1 , wherein the extruder head has a feeding plane that extends orthogonal to the cord plane and parallel to the cord direction, wherein the first extruder and the second extruder are arranged for supplying the extrusion material in a first supply direction and a second supply direction, respectively, wherein the first supply direction and the second supply direction extend parallel to or in the feeding plane, wherein the first pump and the second pump are arranged for receiving the extrusion material from the first extruder and the second extruder in the first supply direction and the second supply direction, respectively, and for directing said extrusion material in or parallel to the feeding plane into the first flow channel and the second flow channel, respectively. 
     
     
         6 . The extruder system according to  claim 1 , wherein the first extruder is arranged for supplying a first compound of the extrusion material into the die via the first flow channel and wherein the second extruder is arranged for supplying a second compound of the extrusion material into the die via the second flow channel. 
     
     
         7 . The extruder system according to  claim 6 , wherein the first compound is chemically different from the second compound. 
     
     
         8 . The extruder system according to  claim 1 , wherein the first pump and the second pump are a first gear pump and a second gear pump, respectively. 
     
     
         9 . A method for extruding cord reinforced extrudate, with the use of an extruder system, wherein the extruder system comprises an extruder head and a first extruder and a second extruder external to the extruder head, wherein the extruder head comprises a die for receiving extrusion material, a cord guide for guiding cords side by side in a common cord plane in a cord direction into the die, a first flow channel that debouches into the die from a first side of the cord plane and a second flow channel debouches into the die from a second side of the cord plane opposite to the first side, wherein the method comprises the steps of:
 guiding cords side by side in the common cord plane in the cord direction into the extruder head, supplying extrusion material from the first extruder and the second extruder to the extruder head;   providing a first pump between the first extruder and the first flow channel and a second pump between the second extruder and the second flow channel, wherein the first pump and the second pump receive the extrusion material from the first extruder and the second extruder and direct said extrusion material into the first flow channel and the second flow channel, respectively;   measuring the pressure of the first compound at or near the output side of the first pump and upstream of or at the entrance to the first flow channel;   measuring the pressure of the second compound at or near the output side of the second pump and upstream of or at the entrance to the second flow channel; and   controlling the speeds of the first pump and the second pump based on the measurements of the pressures of the first compound and the second compound.   
     
     
         10 . The method according to  claim 9 , wherein the extruder head has a feeding plane that extends orthogonal to the cord plane and parallel to the cord direction, wherein the extrusion material is supplied from the first extruder and the second extruder to the extruder head in a first supply direction and a second supply direction which are oblique to the feeding plane, wherein the first pump and the second pump receive the extrusion material from the first extruder and the second extruder in the first supply direction and the second supply direction, respectively, and direct said extrusion material in or parallel to the feeding plane into the first flow channel and the second flow channel, respectively. 
     
     
         11 . The method according to  claim 9 , wherein the extruder head has a feeding plane that extends orthogonal to the cord plane and parallel to the cord direction, wherein the extrusion material is supplied from the first extruder and the second extruder to the extruder head in a first supply direction and a second supply direction which extend parallel to or in the feeding plane, wherein the first pump and the second pump receive the extrusion material from the first extruder and the second extruder in the first supply direction and the second supply direction, respectively, and direct said extrusion material in or parallel to the feeding plane into the first flow channel and the second flow channel, respectively. 
     
     
         12 . The method according to  claim 9 , wherein the first extruder supplies a first compound of the extrusion material and wherein the second extruder supplies a second compound of the extrusion material. 
     
     
         13 . The method according to  claim 12 , wherein the first compound is chemically different from the second compound. 
     
     
         14 . The method according to  claim 9 , wherein the compounds are identical, wherein the speeds of the first pump and the second pump are controlled to supply the first compound and the second compound into the first flow channel and the second flow channel at substantially the same pressure. 
     
     
         15 . The method according to  claim 9 , wherein the first compound and the second compound are different, wherein the speeds of the first pump and the second pump are controlled based on data about the ratios between the pressure and the flow rate for each of the first compound and the second compound, such that the first compound and the second compound at different pressures flow at the same flow rate through or out of the die.