Apparatus and method for manufacturing a green tyre

Abstract

The invention provides an assembly and a method for manufacturing a green tyre. The assembly comprises a building drum ( 52 ), an extrusion device ( 75 ) for extruding a strip ( 70 ) of an unvulcanized rubber, a transfer drum ( 72 ) for helically winding the strip ( 70 ) of the unvulcanized rubber thereon into a layer of rubber material, and a cutting device ( 76 ) for at least substantially in axial direction severing the layer of rubber material, wherein the transfer drum ( 72 ) is movable between a first position near the extrusion device ( 52 ) and a second position near the building drum ( 52 ) for transferring the layer of rubber material from the transfer drum ( 72 ) to the building drum ( 52 ).

1 - 25 . (canceled) 
     
     
         26 . Method for manufacturing a green tyre, comprising the steps of:
 from an extrusion device extruding a strip of an unvulcanized rubber material;   during extruding helically winding the strip on a transfer drum for forming a layer of rubber material;   at least substantially in axial direction severing the layer of rubber material; and   transferring the cut layer of rubber material from the transfer drum onto a building drum by means of substantially simultaneously unwinding the layer from the transfer drum and winding up the layer onto the building drum.   
     
     
         27 . Method according to  claim 26 , wherein the strip is wound into the layer of rubber material over several revolutions of the transfer drum. 
     
     
         28 . Method according to  claim 26 , wherein the extrusion device and the transfer drum are moved with respect to each other in axial direction of the transfer drum during extruding. 
     
     
         29 . Method according to  claim 26 , wherein the layer of rubber material is arranged on the building drum substantially in one revolution thereof. 
     
     
         30 . Method according to  claim 29 , wherein the layer of rubber material is arranged on the building drum by means of a substantially continuous rotation of the building drum. 
     
     
         31 . Method according to  claim 26 , wherein the layer of rubber material is formed using two, three or more extrusion devices, wherein the various extrusion devices extrude rubber components of different compositions. 
     
     
         32 . Method according to  claim 26 , wherein the transfer drum is movable between a first position near the extrusion device and a second position near the building drum for transferring the layer of rubber material from the transfer drum to the building drum. 
     
     
         33 . Method according to  claim 26 , wherein the transfer drum is rotatable about a first axis of rotation and the building drum is rotatable about a second axis of rotation, wherein the first and the second axis of rotation are placed substantially parallel, at least during transferring the cut layer. 
     
     
         34 . Method according to  claim 26 , wherein the rubber material on the transfer drum is forcedly cooled by means of a cooling device in the transfer drum. 
     
     
         35 . Method according to  claim 26 , wherein the rubber material, at least near a cutting zone thereof where the cutting device is able to sever the layer, is retained on the transfer drum by means of a retaining device, wherein the retaining device is a part of the transfer drum. 
     
     
         36 . Method according to  claim 26 , wherein after cutting the layer of rubber material and during transferring the layer of rubber material from the transfer drum to the building drum the outer ends of the layer formed by cutting are kept spaced apart from one another by means of a separation member, wherein during transferring the layer of rubber material from the transfer drum to the building drum, the separation member keeps the outer ends spaced apart substantially in radial direction of the transfer drum. 
     
     
         37 . Assembly for manufacturing a green tyre, comprising
 a building drum,   an extrusion device for extruding a strip of an unvulcanized rubber,   a transfer drum which is arranged for helically winding the strip of the unvulcanized rubber thereon into a layer of rubber material, and   a cutting device for at least substantially in axial direction severing the layer of rubber material,   wherein the transfer drum is movable between a first position near the extrusion device and a second position near the building drum for transferring the layer of rubber material from the transfer drum to the building drum.   
     
     
         38 . Assembly according to  claim 37 , wherein the layer of rubber material is formed of several revolutions of the strip around the transfer drum. 
     
     
         39 . Assembly according to  claim 37 , wherein the diameter of the transfer drum is at least substantially larger or equal to the diameter of the building drum. 
     
     
         40 . Assembly according to  claim 37 , wherein the diameter of the transfer drum is variable. 
     
     
         41 . Assembly according to  claim 37 , provided with two, three or more extrusion devices adapted for extruding rubber components of different compositions. 
     
     
         42 . Assembly according to  claim 37 , wherein the transfer drum is provided with a cooling device for cooling down the rubber material on the transfer drum. 
     
     
         43 . Assembly according to  claim 37 , wherein the transfer drum, at least near a cutting zone thereof where the cutting device is able to sever the layer, comprises a retaining device for retaining the layer of rubber material. 
     
     
         44 . Assembly according to  claim 37 , wherein the transfer drum, at least near a cutting zone thereof where the cutting device is able to sever the layer, comprises a separation member for keeping the outer ends of the layer, formed by severing the layer of rubber material, spaced apart from one another during transferring the layer of rubber material from the transfer drum to the building drum. 
     
     
         45 . Assembly according to  claim 44 , wherein the separation member is adapted for keeping the outer ends spaced apart substantially in radial direction of the transfer drum, during transferring the layer of rubber material from the transfer drum to the building drum, wherein the separation member comprises a surface part of the transfer drum wherein the surface part is rotatably connected to a circumferential surface of the transfer drum, wherein the axis of rotation is situated near or in the circumferential surface of the transfer drum.