Patent ID: 8439117
Filing Date: 2013-05-14
Classification: E21B,F15D,Y10T

Abstract:
1. A variable flow resistance device defining at least one flow path, the flow path comprising: an inlet; a vortex chamber having an outlet; a Y-shaped bi-stable fluidic switch that receives fluid from the inlet and outputs fluid to the vortex chamber alternately along two diverging paths, both of which are tangential to the vortex chamber to produce alternately clockwise and counterclockwise vortices, the switch having first and second control ports; a feedback control circuit that transmits fluid alternately from clockwise and counterclockwise vortices in the vortex chamber to the control ports of the fluidic switch to alternate flow, the feedback control circuit comprising a common section between the first and second control ports through which fluid flows alternately in opposite directions to direct fluid from the vortex chamber alternately to the first and second control ports; and an erosion-resistant liner positioned around the outlet of the vortex chamber.