JPS56163459A - Pipetting apparatus - Google Patents

Abstract

PURPOSE:To change the contact position between the sample tube inner wall and the pipet suction/discharge port in the circumferential direction and prevent a reagent or sample from being contaminated, by rotating the facing position between the pipet suction/discharge port and a sample tube about the vertical axis of said sample tube. CONSTITUTION:When a gear motor rotates simultaneously with the suction operation of the pipet and a machine table sliding cam 25 rotates 60 deg., a machine table 8 is slid forward from a main body 26 by the energization of a coiled spring 27. When the motor rotates 15 deg. further, arm parts 6 and 6' are twisted outward respectively through rocking pieces 14 and 14 by means of cams 16 and cam followers 15. Consequently, the gap between the lower end parts of holding plates 4 is narrowed, so that a sample tube is held between the holding plates 4 through pads 5. When the motor rotates 30 deg. further, sliding pieces 9 and 9' move forward and backward respectively, so that the holding plates make the sample tube 2 rotate on its own vertical axis by means of a frictional force through the pads 5. The hold on the sample tube 2 is released by the subsequent 15 deg. rotation of the motor. The sample tube 2 is brought into the initial state by the subsequent 60 deg. rotation. Thereby, the contact point between the sample tube and the pipet is moved in the circumferential direction by given angles.