Confined pencil blasting apparatus

Abstract

A blasting apparatus includes a first conduit for directing an abrasive stream to a workpiece, and a second conduit for providing a suction force at an outlet of the first conduit and for sucking away particles, the second conduit being disposed substantially surrounding and in parallel to the first conduit.

What is claimed is: 
     
         1 . A blasting apparatus comprising:
 a first conduit for directing an abrasive stream to a workpiece; and   a second conduit for providing a suction force at an outlet of the first conduit and for sucking away particles, the second conduit being disposed substantially surrounding and in parallel to the first conduit.   
     
     
         2 . The blasting apparatus of  claim 1 , wherein an opening of the second conduit at an end thereof is circumferential to the outlet of the first conduit. 
     
     
         3 . The blasting apparatus of  claim 2 , wherein the outlet of the first conduit is withdrawn from the opening of the second conduit by a predetermined distance. 
     
     
         4 . The blasting apparatus of  claim 2 , wherein the opening of the second conduit is an elastic material. 
     
     
         5 . The blasting apparatus of  claim 1 , wherein the second conduit is concentric to the first conduit. 
     
     
         6 . The blasting apparatus of  claim 1 , wherein the second conduit has an elongated portion configured for handheld operation. 
     
     
         7 . The blasting apparatus of  claim 1 , further comprising:
 a stream generator connected to the first conduit for generating the abrasive stream; and   a dust collector external to the workpiece for providing the suction force to the second conduit and for collecting the particles sucked in by the second conduit.   
     
     
         8 . The blasting apparatus of  claim 7 , further comprising a valve for adjusting the abrasive stream, so that an in-flow of the abrasive stream is substantially equivalent to an out-flow of collected particles. 
     
     
         9 . The blasting apparatus of  claim 7 , further comprising a valve for adjusting the suction force of the dust collector, so that an in-flow of the abrasive stream is substantially equivalent to an out-flow of collected particles. 
     
     
         10 . The blasting apparatus of  claim 1 , further comprising a switch for controlling the abrasive stream. 
     
     
         11 . A blasting apparatus comprising:
 a first conduit for directing an abrasive stream to a workpiece; and   a second conduit for providing a suction force at an outlet of the first conduit and for sucking away particles,   wherein the first conduit is disposed inside the second conduit with an opening of the second conduit at an end thereof being circumferential to the outlet of the first conduit, and the first conduit and the second conduit run substantially parallel to each other.   
     
     
         12 . The blasting apparatus of  claim 11 , wherein the outlet of the first conduit is withdrawn from the opening of the second conduit by a predetermined distance. 
     
     
         13 . The blasting apparatus of  claim 11 , wherein the opening of the second conduit is an elastic material. 
     
     
         14 . The blasting apparatus of  claim 11 , wherein the second conduit is concentric to the first conduit. 
     
     
         15 . The blasting apparatus of  claim 11 , wherein second conduit has an elongated portion configured for handheld operation. 
     
     
         16 . The blasting apparatus of  claim 11 , further comprising:
 a stream generator connected to the first conduit for generating the abrasive stream; and   a dust collector for providing the suction force to the second conduit and for collecting the particles sucked in by the second conduit, wherein the dust collector does not enclose the workpiece.   
     
     
         17 . The blasting apparatus of  claim 16 , further comprising a valve for adjusting the abrasive stream, so that an in-flow of the abrasive stream is substantially equivalent to an out-flow of collected particles. 
     
     
         18 . The blasting apparatus of  claim 16 , further comprising a valve for adjusting the suction force of the dust collector, so that an in-flow of the abrasive stream is substantially equivalent to an out-flow of collected particles. 
     
     
         19 . The blasting apparatus of  claim 11 , further comprising a switch for controlling the abrasive stream.