公开(公告)号：JPH02290260A

公开(公告)日：1990-11-30

申请号：JP2035390

申请日：1990-01-30

Applicant: LABSYSTEMS OY

Inventor： KARI JIABIMEEKI ,  YUUA KOIBISUTO ,  MAUNO HEINOONEN

IPC: G01N1/10 ,  B01L3/02 ,  G01N1/00

Abstract: PURPOSE: To make a piston in a pippette cylinder move within a definite range and thereby to enable sucking and discharging a prescribed quantity of liquid by limiting reciprocating motion of a rack by an electric motor via a pinion by means of a limiter. CONSTITUTION: A gear 15 is driven by the motor 10 to move the rack 17 in a main body in an axial direction and the moving of the rack 17 is limited by a fixed limiter 18 at a lower end and by an adjustable limiter 19 at an upper end. A nut knob 21 of the adjustable limiter 19 is connected with a screw 20, a gear of the adjusting knob 21 rotates an axis of a liquid level detector 31 via a gear 30, the liquid level detector 31 is connected with an electronic card and signals are digitized and are converted to liquid crystal display and simultaneously a liquid level range set by a liquid level selecting switch 28 is judged. Limiters 18, 19 and a ram 57 are made of an electric conductor and are connected with the electronic card. When the ram 57 moves and are abutted to the limiter 18 or the limiter 19, moving of the rack 17 is surely stopped and simultaneously the motor 10 is switched-off.