Casting furnace

Abstract

A casting furnace for low pressure casting comprises a furnace chamber, an insert disposed within the furnace chamber, a valve in the insert, a riser to expose a much lower surface of a melt to compressed gas, and a channel for supplying and/or discharging gas into and out of the insert.

1 . A casting furnace for low pressure casting comprising a furnace chamber and an insert for receiving a melt, said insert at least partially disposed within the furnace chamber such that a portion of the insert is in contact with the melt, the insert including a valve for controlling a flow of melt from the furnace into the insert, a riser for feeding melt from the insert into a mold, and a channel for supplying and/or discharging gas into and out of the insert, wherein the valve is comprised an elongated body defining a passage and a post disposed in said passage, said post including a top end wider than said passage and a bottom end wider than said passage. 
     
     
         2 . The casting furnace of  claim 1 , wherein the top end includes a distal end wider than the elongated body. 
     
     
         3 . The casting furnace according to  claim 1  wherein the top end includes a curved surface shaped to mate with a curved surface defining an entrance to the passage. 
     
     
         4 . The casting furnace according to  claim 1  wherein the bottom end comprises a removeable pin passing through a hole in the post. 
     
     
         5 . The casting furnace according to  claim 1  wherein the elongated body includes a groove configured to receive cement. 
     
     
         6 . The casting furnace according to  claim 1  wherein the valve is comprised of a ceramic material. 
     
     
         7 . The casting furnace according to  claim 1  wherein the post is at least 10% longer than the elongated body. 
     
     
         8 . The casting furnace according to  claim 1  wherein the top end has a greater molten metal contacting surface area than the bottom end. 
     
     
         9 . The casting furnace according to  claim 1 , wherein the elongated body includes a conical outer surface. 
     
     
         10 . The casting furnace according to  claim 1  wherein the riser is a cylindrical body including an integral ridge disposed between a first and second end, the ridge having rounded corners at an interface with the cylindrical body. 
     
     
         11 . The casting furnace according to  claim 1  including a trough joined to the riser, said trough including a cylindrical depending first end, a cylindrical depending second end, and a open top intermediate section extending between the depending first and second ends. 
     
     
         12 . A casting furnace for low pressure casting comprising a furnace chamber and an insert for receiving a melt, said insert is at least partially disposed within the furnace chamber such that a portion of the insert is in contact with the melt, the insert including a valve for controlling a flow of melt from the furnace into the insert, a riser for feeding melt from the chamber into a mold, and a channel for supplying and/or discharging gas into and out of the insert, wherein the insert includes a rim extending from a cup-shaped body, and wherein the lower most intersection between the rim and cup-shaped body is a curved surface, and wherein a bottom wall of the cup-shaped body includes a curved surface at an intersection of a side-wall of the cup-shaped body and the bottom wall. 
     
     
         13 . The casting furnace of  claim 12  including a metallic frame enclosing a refractory disc forming a lid. 
     
     
         14 . The casting furnace of  claim 13  including at least one gasket between the rim and the furnace chamber. 
     
     
         15 . The casting furnace of  claim 12 , wherein an internal surface of the bottom wall includes a partition wall extending at each end from the side wall and surrounding the valve. 
     
     
         16 . The casting furnace of  claim 13 , wherein the frame includes a first ring above the rim and a second ring below the rim, said rings being coupled by at least one fastener. 
     
     
         17 . The casting furnace of  claim 16 , wherein the first ring includes at least one lifting element.