High Vessel Outlet

Abstract

Embodiments of an outlet tube assembly for use with a dispensing vessel are disclosed. The dispensing vessel has a side wall defining a chamber; the side wall has an upper portion and has a lower portion that tapers downwardly to an outlet. The outlet tube assembly facilitates accurate measurement of a particulate material level within the dispensing vessel and/or reduces contamination of the particulate material.

We claim: 
     
         1 . A dispensing assembly, comprising:
 a dispensing vessel comprising a side wall that defines a chamber suitable to contain particulate material, wherein the side wall has an upper portion and has a lower portion that tapers downwardly to an outlet; and   an outlet tube assembly connected to the dispensing vessel, the outlet tube assembly comprising a tube having an inlet and an outlet in fluid communication with the inlet, wherein the tube extends upwardly through the outlet of the dispensing vessel, and wherein the tube has a sufficient length that the tube inlet is positioned to receive particulate material at or above the top of the lower portion of the side wall.   
     
     
         2 . The dispensing assembly of  claim 1 , wherein the upper portion of the side wall is substantially vertical. 
     
     
         3 . The dispensing assembly of  claim 1 , further comprising a level sensor located in the chamber. 
     
     
         4 . The dispensing assembly of  claim 3 , wherein the level sensor has a lower end positioned at a height below the tube inlet. 
     
     
         5 . The dispensing assembly of  claim 1 , wherein the outlet tube assembly further comprises a base having an aperture therethrough that is dimensioned to receive the tube, wherein the aperture is in fluid communication with the outlet of the tube and the tube outlet is located within the aperture. 
     
     
         6 . The dispensing assembly of  claim 5 , wherein the base has an outer horizontal dimension greater than or equal to an inner horizontal dimension of the outlet of the dispensing vessel. 
     
     
         7 . The dispensing assembly of  claim 5 , wherein the tube is removably coupled to the base. 
     
     
         8 . The dispensing assembly of  claim 5 , wherein the outlet tube assembly has a unitary construction. 
     
     
         9 . The dispensing assembly of  claim 5 , wherein the base is attached to the dispensing vessel outlet. 
     
     
         10 . The dispensing assembly of  claim 9 , wherein the base is removably attached to the dispensing vessel outlet. 
     
     
         11 . The dispensing assembly of  claim 1 , wherein the dispensing vessel has a dispensing vessel inlet. 
     
     
         12 . The dispensing assembly of  claim 11 , wherein the dispensing vessel inlet is coupled to a particulate material source such that particulate material can be transferred into the chamber via the dispensing vessel inlet. 
     
     
         13 . The dispensing assembly of  claim 12 , further comprising a stagnant bed of the particulate material in the chamber. 
     
     
         14 . The dispensing assembly of  claim 1 , wherein at least a portion of an inner surface of the tube comprises a ceramic, graphite, glass, a martensitic stainless steel alloy, or a microcellular elastomeric polyurethane. 
     
     
         15 . The dispensing assembly of  claim 1 , wherein the tube comprises an upper tube portion coupled to a lower tube portion. 
     
     
         16 . The dispensing assembly of  claim 15 , wherein the upper tube portion and the lower tube portion are constructed of different materials. 
     
     
         17 . The dispensing assembly of  claim 15 , wherein the upper tube portion comprises a ceramic, graphite, glass, or a martensitic steel alloy. 
     
     
         18 . The dispensing assembly of  claim 15 , wherein at least a portion of an inner surface of the upper tube portion, an inner surface of the lower tube portion, or an inner surface of the upper tube portion and an inner surface of the lower tube portion is coated with a microcellular elastomeric polyurethane. 
     
     
         19 . A dispensing assembly for dispensing particulate polysilicon with mitigation of polysilicon contamination, comprising:
 a dispensing vessel comprising a side wall that defines a chamber suitable to contain particulate polysilicon, wherein the side wall has an upper portion and has a lower portion that tapers downwardly to an outlet; and   an outlet tube assembly comprising a tube having an inlet and an outlet in fluid communication with the inlet, wherein the tube extends upwardly through the outlet of the dispensing vessel, wherein the tube has a sufficient length that the tube inlet is positioned to receive particulate material at or above the top of the lower portion of the wall, and wherein at least a portion of an inner surface of the tube comprises a ceramic, graphite, glass, a martensitic steel alloy, or a microcellular elastomeric polyurethane coating.   
     
     
         20 . The dispensing assembly of  claim 19 , wherein the outlet tube assembly further comprises a base having an aperture therethrough that is dimensioned to receive the tube, wherein the aperture is in fluid communication with the outlet of the tube and the tube outlet is located within the aperture. 
     
     
         21 . The dispensing assembly of  claim 20 , wherein at least a portion of the inner surface of the tube comprises silicon carbide, silicon nitride, graphite, quartz, a martensitic stainless steel alloy, or a microcellular elastomeric polyurethane. 
     
     
         22 . The dispensing assembly of  claim 19 , further comprising a level sensor located in the chamber, wherein the level sensor has a lower end positioned at a height below the tube inlet.