Apparatus and method for casting metallic materials

Abstract

Apparatus for casting metallic materials, includes a processing device for preparing metallic material in free-flowing form and a storage container in communication with the processing device for receiving a continuous flow of prepared metallic material. An injection unit including a piston and cylinder arrangement is arranged separately from and connected to the storage container by a flow connection which includes a flow regulating device to control a flow therethrough. The storage container and the piston and cylinder arrangement are heated separately by a heating assembly, thereby ensuring short cycle times and establishment of great variability during a casting operation.

What is claimed is:  
     
         1 . Apparatus for casting metallic materials, comprising: 
 a processing device for preparing metallic material in free-flowing form;    a storage container in communication with the processing device for receiving a continuous flow of prepared metallic material;    an injection unit including a piston and cylinder arrangement arranged separately from the storage container;    a flow connection for linking the storage container with the injection unit, said flow connection having a flow regulating device to close and open the flow connection; and    a heating assembly including a first heating device for the storage container and a second heating device for the piston and cylinder arrangement.    
     
     
         2 . The apparatus of  claim 1 , wherein the metallic material is processed in the processing device at a temperature above a liquidus temperature to effect a homogenous, completely liquid phase.  
     
     
         3 . The apparatus of  claim 1 , wherein the metallic material is processed in the processing device at a temperature above a solidus temperature but not exceeding a liquidus temperature so as to realize a material with liquid and solid phases.  
     
     
         4 . The apparatus of  claim 1 , and further comprising an agitating device for stirring the metallic material in the storage container.  
     
     
         5 . The apparatus of  claim 4 , wherein the agitating device is a mechanical agitating device.  
     
     
         6 . The apparatus of  claim 4 , wherein the agitating device is an electromagnetic agitating device.  
     
     
         7 . The apparatus of  claim 4 , and further comprising a static mixer disposed in the flow connection between the storage container and the injection unit.  
     
     
         8 . The apparatus of  claim 1 , wherein the storage container is constructed for operation with a variable fill level of processed metallic material.  
     
     
         9 . The apparatus of  claim 8 , wherein the storage container includes a variable gas volume above the fill level of prepared metallic material.  
     
     
         10 . The apparatus of  claim 8 , wherein the flow connection enters the storage container at an area below a minimum fill level of prepared metallic material.  
     
     
         11 . The apparatus of  claim 8 , wherein the flow connection enters the storage container at an area above a maximum fill level of prepared metallic material.  
     
     
         12 . The apparatus of  claim 8 , wherein the gas volume has a pressure which is controlled at a substantially constant pressure value.  
     
     
         13 . The apparatus of  claim 8 , wherein the gas volume includes inert gas.  
     
     
         14 . The apparatus of  claim 8 , wherein the gas volume is part of a through-flow system.  
     
     
         15 . The apparatus of  claim 14 , wherein the gas volume is part of a closed through-flow system.  
     
     
         16 . The apparatus of  claim 1 , wherein the piston and cylinder arrangement has a cylinder in a substantially vertical disposition.  
     
     
         17 . The apparatus of  claim 1 , wherein the piston and cylinder arrangement includes a cylinder in a substantially horizontal disposition.  
     
     
         18 . The apparatus of  claim 1 , wherein the piston and cylinder arrangement includes a piston having a circumference, which is formed with at least one groove, and a sealing ring received in the groove, said piston having an end face formed with an orifice connected to the groove by at least one channel at the circumference of the piston.  
     
     
         19 . The apparatus of  claim 1 , wherein the flow regulating device includes a check valve disposed in the flow connection between the storage container and the injection unit.  
     
     
         20 . The apparatus of  claim 1 , wherein the flow regulating device includes an actively closeable valve disposed in the flow connection between the storage container and the injection unit.  
     
     
         21 . The apparatus of  claim 1 , wherein the processing device includes an extruder.  
     
     
         22 . The apparatus of  claim 21 , wherein the extruder moves the metallic material in a transport direction and defines a longitudinal axis which is inclined downwards in the transport direction relative to a horizontal at an angle of 0° to 45°, said extruder having a discharge end for directly introducing the metallic material into the storage container at a level below a minimum fill level of the prepared metallic material.  
     
     
         23 . The apparatus of  claim 21 , wherein the extruder has a discharge end for introducing the metallic material into the storage container at a level above a maximum fill level of the prepared metallic material.  
     
     
         24 . The apparatus of  claim 21 , wherein the processing device includes a feed unit for supply of metallic starting material into the extruder in controlled doses.  
     
     
         25 . The apparatus of  claim 24 , wherein the feed unit is operated to supply a reduced amount of starting material to the extruder.  
     
     
         26 . The apparatus of  claim 24 , wherein the starting material is a solid material, said heating assembly including a third heating device for the feed unit for heating the solid material.  
     
     
         27 . A method of molding a metallic material, comprising the steps of: 
 continuously preparing metallic material in free-flowing form;    feeding the metallic material to a storage container with constant volume and variable fill level;    periodically transferring the metallic material into an injection unit with a piston and cylinder arrangement; and    injecting the metallic material by the injecting unit into a molding tool, wherein the piston and cylinder arrangement of the injection unit and the storage container are heated separately and independently from one another.    
     
     
         28 . The method of  claim 27 , wherein the preparing step includes the step of heating a starting material to a temperature above a solidus temperature but not exceeding a liquidus temperature so that the thus-prepared metallic material has liquid and solid phases.  
     
     
         29 . The method of  claim 28 , wherein the preparing step includes the step of heating a starting material to a temperature above a liquidus temperature so that the thus-prepared metallic material has a completely liquid phase.  
     
     
         30 . The method of  claim 27 , wherein the prepared metallic material in the storage container is subject to a shearing action to reduce forming dendritic structures.  
     
     
         31 . The method of  claim 27 , wherein the prepared metallic material in the storage container is maintained under an inert gas volume.  
     
     
         32 . The method of  claim 27 , wherein the piston and cylinder arrangement has a piston which is actively moved independently on the introduction of metallic material into the injection unit.  
     
     
         33 . The method of  claim 28 , wherein the starting material is a solid material.  
     
     
         34 . The method of  claim 28 , wherein the starting material is pre-heated.