Patent ID: 6883958

Claim:
An apparatus for engaging and moving a mixer disposed in an uncovered, upstanding specimen container, the top of the mixer having a cavity defined by an upstanding annular wall, the apparatus comprising: a holder adapted to releasably engage the annular wall of the mixer, the holder mounted above the container for vertical movement relative thereto and comprising a collet having flexible fingers that fit within the cavity of the mixer and are expandable to engage the inner surface of the annular wall; a clamping actuator for selectively causing the holder to engage or release the annular wall of the mixer by selectively moving the fingers radially to expand or contract the collet into or out of engagement with the inner surface of the annular wall of the mixer, wherein the clamping actuator comprises an axially movable central plunger within the collet interior, at least one of the plunger and the interior having a tapered surface, whereby axial movement of the plunger causes radial movement of the fingers; and a vertical actuator for moving the holder along a vertical axis.