Dust boot and ball joint structure

A ball joint structure, comprising:

• a ball socket comprising a ball socket space;
• a ball pin comprising a spherical portion and a shafting portion, wherein the spherical portion is connected to the shafting portion, and when the ball pin is inserted into the ball socket, the spherical portion is accommodated in the ball socket space;
• and
• a dust boot encasing on the shafting portion and an upper end of the ball socket, the dust boot comprising:
• a covering body comprising a covering space, a first annular edge and a second annular edge, wherein the shafting portion is disposed through the covering space, and the upper end of the ball socket is accommodated in the covering space, the second annular edge is opposite to the first annular edge, a diameter of the second annular edge is greater than a diameter of the first annular edge;
• an inner bundling body disposed on the covering body, being adjacent to the first annular edge and abutting against the shafting portion, the inner bundling body protruding radially toward the covering space;
• an inner bundling ring located inside the inner bundling body and covered by the inner bundling body, the inner bundling ring comprising a ring portion and a bundle portion, wherein the bundle portion protrudes downwardly along an axis from an inner edge of the ring portion;
• a channel disposed in the inner bundling body and communicating with the covering space, the channel located in a bottom of the ring portion and an outside of the bundle portion;
• and
• an oil draining hole passing through the covering body and communicating with the channel, wherein the oil draining hole allows an oil to drain from the covering space.