Patent ID: 7024729

Claim:
A rotation apparatus for connecting a first body to a second body, comprising: a sleeve having one end including a stopper and an outer wall including screw threads; a retaining means for engaging with said sleeve; a first base connected to the first body above the retaining means, wherein the first base has a first opening; a second base connected to the second body above the first base, wherein the second base has a second opening, the second opening has a shape that matches the outer wall of the sleeve; and a rotation-limiting ring located between the first base and the second base, the first base furthermore comprises a protruding pin, the outer edge of the rotation-limiting ring has a pair of engaging means for engaging with the protruding pin, the inner edge of the rotation-limiting ring has a profile that matches the outer wall of the sleeve, and the sleeve passes through the rotation-limiting ring so that the rotation-limiting ring can rotate when driven by the angular movement is limited by the engaging means, wherein the sleeve passes through the first opening of the first base and the second opening of the second base and screws into the retaining means so that the sleeve is able to rotate by moving the second base.