US Patent 7207890 Tubular telescoping drive shaft

A tubular telescoping drive shaft for transmitting rotation from a rotating power source to an element to be rotated thereby, including at least one inner member or shaft telescopically receivable in an outer tubular shaft and including a universal joint such as a Hooke's joint having pivotal yokes connected with a cross link, all of which are at least substantially received within the outer tubular shaft in a fully retracted position and are rotatably pivotable therein for accommodating misalignment of the rotating power source and element rotated thereby.