Extrusion press, in particular a short stroke extrusion press, for producing metal extrudates by extruding a billet

Abstract

An extrusion press for producing metal extrudates by extruding a billet, the extrusion press comprising:a punch holder crosspiece which carries a punch and is adapted to be translated in two opposite senses of translation along a first extrusion direction;a billet holder loader adapted to be alternately positioned between a resting position and a loading position;wherein said punch holder crosspiece is translatable along a second direction, perpendicular to said first extrusion direction, between a first position thereof and a second position thereof;wherein when the billet holder loader is in said resting position and said punch holder crosspiece is in the first position thereof, the translation of the punch holder crosspiece along said first extrusion direction in a first sense of translation, or sense of extrusion, causes a push by said punch against said billet and the extrusion of said billet;characterized in that said extrusion press comprises restraining means adapted to mutually restrain said punch holder crosspiece and said billet holder loader; and in that when the punch holder crosspiece is in the first position, it is restrained to the billet holder loader by means of said restraining means so that the translation of said punch holder crosspiece from the first position to the second position causes the movement of the billet holder loader from said resting position to said loading position.

1 . An extrusion press for producing metal extrudates by extruding a billet, the extrusion press comprising:
 a punch holder crosspiece which carries a punch and is adapted to be translated in two opposite senses of translation along a first extrusion direction;   a billet holder loader adapted to be alternately positioned between a resting position and a loading position, the loading position in particular being a position wherein the billet is arranged on the billet holder loader along the first extrusion direction;
 wherein said punch holder crosspiece is translatable along a second direction, perpendicular to said first extrusion direction, between a first position thereof and a second position thereof; 
 wherein when the billet holder loader is in said resting position and said punch holder crosspiece is in the first position thereof, the translation of the punch holder crosspiece along said first extrusion direction in a first sense of translation, or sense of extrusion, causes a push by said punch against said billet and the extrusion of said billet; 
 wherein said extrusion press comprises restraining means adapted to mutually restrain said punch holder crosspiece and said billet holder loader; 
 wherein when the punch holder crosspiece is in the first position, it is restrained to the billet holder loader by means of said restraining means so that the translation of said punch holder crosspiece from the first position to the second position causes the movement of the billet holder loader from said resting position to said loading position; 
 wherein when said billet holder loader is in said resting position, the translation of said punch holder crosspiece along said first extrusion direction in said sense of extrusion, in particular to extrude the billet, causes the mutual release of said punch holder crosspiece and said billet holder loader. 
   
     
     
         2 . The press according to  claim 1 , wherein the punch holder crosspiece can take on a third position wherein the punch is at least partially inserted into a container adapted to at least partially contain said billet during the extrusion of said billet;
 and wherein by passing from the first position to the third position, the punch holder crosspiece ( 20 ) is released from the billet holder loader.   
     
     
         3 . The press according to  claim 1 , configured so that the billet holder loader moves from the resting position to the loading position by being dragged by the punch holder crosspiece which moves from the first position thereof to the second position thereof. 
     
     
         4 . The press according to  claim 1 , wherein when the punch holder crosspiece is in the second position, it is restrained to the billet holder loader by means of said restraining means so that the translation of said punch holder crosspiece from the second position to first position causes the movement of the billet holder loader from said loading position to said resting position; the extrusion press in particular being configured so that the billet holder loader moves from the loading position to the resting position by being pushed by the punch holder crosspiece which moves from the second position thereof to the first position thereof. 
     
     
         5 . The press according to  claim 1 , configured so that when said billet holder loader is in said resting position, a translation of said punch holder crosspiece along said first extrusion direction in sense opposite to said sense of extrusion causes the mutual restraint of said punch holder crosspiece-and said billet holder loader. 
     
     
         6 . The press according to  claim 1 , comprising a container adapted to at least partially contain said billet during the extrusion of said billet; in particular wherein the press is configured so that when the punch is outside the container, the punch holder crosspiece and the billet holder loader ( 24 ) are restrained to each other by means of said restraining means. 
     
     
         7 . The press according to  claim 1 , wherein, in particular in use, said punch holder crosspiece and said billet holder loader are restrainable to each other by means of said restraining means and are releasable from each other according to the position along the extrusion direction of the punch holder crosspiece. 
     
     
         8 . The press according to  claim 1 , wherein said restraining means comprise a first restraining element which is integral with said punch holder crosspiece, and a second restraining element which is integral with said billet holder loader. 
     
     
         9 . The press according to  claim 8 , wherein said restraining means are configured, in use, to restrain and release said punch holder crosspiece and said billet holder loader to/from each other when the punch holder crosspiece is translated along the extrusion direction. 
     
     
         10 . The press according to  claim 8 , wherein said first restraining element comprises a first surface and second surface distinct from each other, and the second restraining element comprises a first surface and second surface distinct from each other, the first surface of the first restraining element facing the first surface of the second restraining element, and the second surface of the first restraining element facing the second surface of the second restraining element when the first restraining element and the second restraining element are restrained to each other. 
     
     
         11 . The press according to  claim 8 , wherein said first restraining element is a hook or is hook-shaped, and said second restraining element is a tooth. 
     
     
         12 . An extrusion plant for producing metal extrudates by extruding a billet, comprising an extrusion press according to  claim 1 . 
     
     
         13 . An extrusion method for producing metal extrudates by extruding a billet by means of an extrusion press according to  claim 1 , wherein there is provided a step in which the punch holder crosspiece is translated from the first position to the second position, and wherein the translation of said punch holder crosspiece from the first position to the second position causes the movement of the billet holder loader from said resting position to said loading position; in particular, wherein the billet holder loader is moved from the resting position to the loading position by being dragged by the punch holder crosspiece which moves from the first position thereof to the second position thereof; wherein there is provided a step in which the punch holder crosspiece and the billet holder loader are released from each other by translating the punch holder crosspiece along said first extrusion direction in the sense of extrusion. 
     
     
         14 . The method according to  claim 13 , wherein there is provided a step in which the punch holder crosspiece is translated from the second position to the first position, and wherein the translation of said punch holder crosspiece from the second position to the first position causes the movement of the billet holder loader from said loading position to said resting position; in particular wherein the billet holder loader moves from the loading position to the resting position by being pushed by the punch holder crosspiece-which moves from the second position thereof to the first position thereof. 
     
     
         15 . The method according to  claim 13 , wherein there is provided a mutual restraining step between the billet holder loader and the punch holder crosspiece by means of said restraining means; in particular wherein said restraining step provides the translation of the punch holder crosspiece along said first extrusion direction in sense opposite to the sense of extrusion.