Patent ID: 7138574

Claim:
A drum tuning system comprised of: a cylindrical drum body; an annular member, a circular ring where the inside diameter of said annular member is slightly larger in diameter than the outside diameter of said cylindrical drum body, which when attached encircles said cylindrical drum body just below the top of the open end of said cylindrical drum body, said annular member incorporating a single continuous spiraling groove track that starts at the top of said annular member along it's outside diameter continuing in a spiral fashion around the outer circumference of said annular member eventually exiting at the bottom of said annular member, said spiral grooved track forming a single large cam surface; a larger circular ring assembly made up of two components that fit over and encompass said annular member, the first component being a rotating actuator ring retainer having a larger diameter than the outside diameter of said annular member, and a second component having a smaller inner ring with nearly the same diameter as the rim of the drum head; said rotating actuator ring retainer overlaps and rotates on said inner ring, said inner ring does not rotate but rides on and exerts pressure on the rim of said drum head when fitted over the open end of said cylindrical drum body; said rotating actuator ring retainer incorporating inward facing projections or rollers on the inside diameter located at opposing intervals and mounted at varied heights to compensate for the angle or pitch of said spiral groove cam track of said annular member, said angle or pitch of said spiral groove cam track being responsible for the camming action created as said projections or rollers on said rotating actuator ring retainer engage said annular member's spiral groove cam track during rotation, the compensating height of said projections or rollers constructed to keep said rotating actuator ring retainer aligned perpendicular to said drum head rim and open end of said cylindrical drum body; clockwise or counterclockwise rotation of said rotating actuator ring retainer simultaneously and evenly varies the tension or stretching of said drum head, which thereby tunes the drum.