Abstract: A pipette controller comprising a coil spring arranged in a cylinder between the bottom of the cylinder and the piston for biasing said piston to a predetermined position in which a graduate reading plunger in thread engagement with a threaded rod mounted on a piston projects through a hole in the top of a cylinder cap, and a double-sealing means adapted to be engaged with a port formed on the bottom of the cylinder for sealing the end of a pipette to the controller with the interior of the pipette in communication with the chamber defined by the piston and cylinder.A lever assembly is provided which vents the interior of the cylinder to facilitate gravity drainage of the pipette. Both the plunger and the lever assembly can be operated easily with one hand.

Abstract: This invention provides a pipette controller comprising a cylinder-piston assembly with facilities of graduate reading device for presetting the volume of liquid to be pipetted, a hand control for natural drainage of liquid and heat barrier for preventing quick penetration of ambient temperature or operator's body temperature, such that convenient operation and excellent control of pipetting may be obtained.