Patent ID: 7169355

Claim:
An apparatus for thermally cycling biological samples, comprising: a sample block having a plurality of openings for receiving samples of a sample well tray therein, the sample wells having closed sample well bottoms configured to contain a sample, the plurality of openings for receiving sample wells being configured to contact an outer surface of a corresponding sample well; a sample well tray holder for holding the sample well tray therein, said sample well tray being movable relative to the sample well tray holder; and a plurality of leaf springs interposed between the sample block and the sample well tray holder, the plurality of leaf springs configured to impart an urging force on the sample well tray via the sample well tray holder, said plurality of leaf springs creating an urging force to urge the sample wells away from the openings in the sample block upon removal of a pressing force imparted on the top of the sample well tray for pressing the sample wells into the openings of the sample block.