Patent ID: 7232533

Claim:
An apparatus comprising a hollow shaft having a first end, a second end, a mid-section and at least one opening in said mid-section; a separator member centrally attached to said hollow shaft proximal to said mid-section; said separator member having a first surface, a second surface located opposite said first surface, a peripheral region in contact with both said first and second surfaces and a central region, wherein said peripheral region forms a taper from said central region; a webbed portion in said central region of said separator member configured to form at least one annular cavity around said at least one opening in said mid-section of said hollow shaft; a first cover member centrally attached to said hollow shaft proximal to and separated from said first surface of said separator member; a second cover member centrally attached to said hollow shaft proximal to and separated from said second surface of said separator member; and a spindle that is connected to said hollow shaft.