Patent ID: 6799641
Filing Date: 2004-10-05
Classification: E21B

Abstract:
A fluid channeling device for a percussive drill, the drill including a casing having an interior space, a drive chamber and a valve chamber each being defined within the casing interior space, a piston movably disposed within the casing and having an upper end disposeable within the drive chamber and a longitudinal through-bore, a valve configured to control flow into the drive chamber and having a surface bounding a section of the valve chamber, the channeling device comprising:a first member disposed at least partially within the drive chamber so as to extend into the piston bore when the piston upper end is located within the drive chamber, the first member having an outer surface, an interior space and at least one port extending between the outer surface and the interior space and fluidly connectable with the drive chamber; and a second member disposed at least partially within the first member interior space and having a passage fluidly connected with the valve chamber and fluidly connectable with the port so as to establish fluid communication between the drive chamber and the valve chamber.