Patent ID: 8333526

Claim:
A three-degree-of-freedom universal joint, comprising: a first connecting base comprising a base body and two first hinge blocks formed on the base body and spaced from each other, wherein a first axis passes through the two first hinge blocks; a second connecting base comprising a baseboard and two second hinge blocks formed on the baseboard and spaced from each other, wherein a second axis passes through the two second hinge blocks; wherein in an assembled state, the first axis is perpendicular to the second axis, and the first axis intersects the second axis at an assembly space formed between the first hinge blocks and second hinge blocks; a two-way hinged member disposed within the assembly space and connected to the first and second hinge blocks for hinging the second connecting base relative to the first connecting base about the first axis and the second axis; and a third connecting base rotatably assembled to the baseboard of the second connecting base on a side of the baseboard opposite the second hinge blocks, wherein the third connecting base is rotatable about a third axis that is substantially perpendicular to the first and second axes; wherein the third connecting base comprises: a hollow main body, the main body having an assembly end adjacent the baseboard of the second connecting base, and a connecting end opposite the assembly end, said connecting end being adapted to connect to an external device; a rotary shaft, the rotary shaft having opposite first and second ends, with the first end disposed within the main body and the second end extending outwardly from the assembly end and secured to the baseboard of the second connecting base; and a tapered roller bearing, an inner peripheral wall of the roller bearing being rotatably engaged with the rotary shaft adjacent the first end of the rotary shaft, and an outer peripheral wall of the roller bearing being engaged with an inner wall of the main body.