| 摘要 |
PURPOSE:To freely vary the stroke and speed of a piston of a pipetting device employing a cylinder, by driving the piston of the cylinder by means of a motor, and controlling the speed and rotational angle of the motor. CONSTITUTION:A pinion 7 is rotated by means of a pulse motor 8 to move a rack 6 downward. At the same time, a piston 2 is moved downward to suck a diluting liquid from a cylinder mouth 1a. After a given amount of the diluting liquid has been sucked, the pulse motor 8 is stopped. Then, the cylinder mouth 1a is separated from the diluting liquid, and the motor 8 is rotated again for a short period of time to move the piston 2 slightly downward in order to suck air. Then, the motor 8 is rotated again to suck a smaple from the cylinder mouth 1a, and after a given amount of the sample has been sucked, the motor 8 is stopped. The sample and the diluting liquid thus sucked in the cylinder 1 are discharged by reversing the pulse motor 8. |
