Pump device for casting processes

Abstract

A pump device includes a drive unit, a pump unit and a transport unit. The drive unit includes a base frame, and a variable-speed drive device disposed on the base frame. The pump unit includes a rotating shaft driven by the drive device, a fan blade co-rotatably mounted to the rotating shaft, a drain housing receiving the fan blade, and a suction housing in fluid communication with the drain housing. The transport unit includes a plurality of transport tubes in fluid communication with the drain housing.

What is claimed is: 
     
         1 . A pump device comprising:
 a drive unit including a base frame, and a variable-speed drive device that is disposed on said base frame;   a pump unit including a rotating shaft that is driven by an output shaft of said drive device and that extends downwardly from said drive device, a fan blade that is co-rotatably mounted to a bottom portion of said rotating shaft, a drain housing that receives said fan blade therein and that has a drain opening and an inlet opening, and a suction housing that defines a suction space in fluid communication with said inlet opening of said drain housing, and a plurality of suction holes in fluid communication with said suction space; and   a transport unit including a plurality of transport tubes that are connected in series and that are in fluid communication with said drain opening of said drain housing;   wherein, when said drain housing and said suction housing of said pump unit are immersed in a melted material, said drive device is operable to rotate said rotating shaft and said fan blade, so that the melted material in said drain housing is impelled by said fan blade to flow into said transport tubes via said drain opening, and that the melted material surrounds said suction housing flows into said drain housing via said suction holes, said suction space and said inlet opening.   
     
     
         2 . The pump device as claimed in  claim 1 , wherein the sum of the areas of said suction holes is equal to or greater than the area of said drain opening. 
     
     
         3 . The pump device as claimed in  claim 2 , wherein the sum of the areas of said suction holes is no more than 10 percent greater than the area of said drain opening. 
     
     
         4 . The pump device as claimed in  claim 1 , wherein said drive device is configured as a six-pole motor. 
     
     
         5 . The pump device as claimed in  claim 1 , wherein said drive device has a rated power of 2 horsepower and a maximum rotational speed of 1500 rpm. 
     
     
         6 . The pump device as claimed in  claim 1 , wherein said transport unit further includes a plurality of electroplated layers each of which is formed on an inner surface of a respective one of said transport tubes, and is made of one of Teflon and a mixture of nickel and phosphorus. 
     
     
         7 . The pump device as claimed in  claim 1 , wherein said transport unit further includes a plurality of heat-insulation sleeves that are respectively sleeved on said transport tubes. 
     
     
         8 . The pump device as claimed in  claim 7 , wherein said transport unit further includes a plurality of heat-insulation cotton layers each of which is disposed between a respective one of said transport tubes and a corresponding one of said heat-insulation sleeves. 
     
     
         9 . The pump device as claimed in  claim 8 , wherein said transport unit further includes a handle that is fixedly mounted on a distal one of said transport tubes distal from said drain opening. 
     
     
         10 . The pump device as claimed in  claim 1 , wherein said base frame of said drive unit includes a plurality of support rods, a heat-insulation plate that is fixedly mounted to top ends of said support rods, and a carrier plate that is fixedly mounted to a top surface of said heat-insulation plate and that permits said drive device to be fixedly mounted thereon, said rotating shaft extending downwardly through said carrier plate and said heat-insulation plate. 
     
     
         11 . The pump device as claimed in  claim 10 , wherein said drive unit further includes a connecting frame that is fixedly mounted to said carrier plate, said connecting frame being adapted to be connected to a casting machine.