Patent ID: 7434843

Claim:
An apparatus comprising a coaxial fluid rotary joint, the coaxial fluid rotary joint comprising: a first generally annular structure; a second generally annular structure surrounded by the first annular structure and coaxially aligned with the first annular structure; a bearing disposed between the first and second annular structures to enable at least one of the annular structures to rotate relative to the other annular structure about a common axis; an internal fluid channel formed between an outer surface of the second annular structure and an inner surface of the first annular structure; an input port in fluid communication with the fluid channel; and an output port in fluid communication with the fluid channel, wherein the first generally annular structure comprises a first wall and a second wall that is perpendicular to the first wall, wherein the second wall extends from the first wall towards the second generally annular structure, the second generally annular structure comprises a first wall and a second wall that is perpendicular to the first wall, wherein the second wall extends from the first wall towards the first generally annular structure, and the second wall of the first generally annular structure contacts the second wall of the second generally annular structure.