| 摘要 |
PURPOSE:To enable execution of a highly precise control in a wide range by providing two means which change liquid discharge amounts by a change in a speed of repetition of increase and decrease of a capacity by a motor torque and by a change in the length of a stroke, respectively, and by executing a control by the latter means in a sphere of insufficient torque. CONSTITUTION:A first means which changes a liquid discharge amount by a control of the reciprocating motion of a plunger of a pump 3a by an inverter 2a, and a second means which changes the liquid discharge amount by a change in the length of a stroke of the plunger of the pum 3a by a pump stroke regulator 5a, are provided. The same constitution is provided also in regard to a pump 3b, and the two means are controlled by a controller 1. Controlled liquids A and B are discharged from these pumps 3a and 3b in a pair, mixed in a merging pipe 9 and made to flow downstream. Thereby a concentration gradient of high precision can be prepared. |
