Patent ID: 8220555

Claim:
A downhole shifting mechanism comprising: a. an inner tubular member; b. an outer tubular member disposed about the inner tubular member; c. a piston disposed between the inner tubular member and the outer tubular member; d. a first set of teeth disposed about an outer diameter of the inner tubular member; e. a sliding block connected to the piston, wherein the piston moves the sliding block about the first set of teeth, wherein the sliding block comprises a second set of teeth configured to slide about the first set of teeth when moving in a first direction, wherein the second set of teeth engage the first set of teeth when traveling in a second direction, and wherein the sliding block moves the inner tubular member when the first set of teeth are engaged with the second set of teeth; f. a body lock ring disposed between an inner diameter of the outer tubular member and the first set of teeth, wherein the body lock ring is fixed relative to the outer tubular member, wherein the body lock ring comprises a third set of teeth configured to slide about the first set of teeth when the sliding block moves the inner tubular member, and wherein the third set of teeth engage the first set of teeth when the second set of teeth are sliding about the first set of teeth; g. a first flow path to provide fluid communication between an inner bore of the inner tubular member and a piston first end; and h. a second flow path to provide fluid communication between an outer diameter of the outer tubular member and a piston second end, wherein the second flow path and the first flow path are isolated from one another.