| 摘要 |
<p>Provided is a liquid delivery device in which pressure fluctuations are small, regardless of the type of liquid being delivered and the temperature thereof. When an inlet-side check valve (12a) and an outlet-side check valve (13a) of a first cylinder (7a) are both closed, and compression of an eluent inside the first cylinder (7a) is started by means of a first plunger (6a) inside the first cylinder (7a), a control unit (15) doubles the rotational speed of a step motor (15a), and measures the amount of change in the pressure inside the first cylinder (7a) which changes for a prescribed time by means of a first cylinder internal pressure detector (18a). The time elapsed until the pressure inside the first cylinder is the same as the pressure inside a discharge-side flow passage is predicted using the rate of change over time of the pressure of the eluent, calculated on the basis of the abovementioned amount of change in pressure. When the predicted elapsed time has elapsed, the rotational speed of the step motor (15a) is returned to the original speed, and the compression of the eluent inside the first cylinder (7a) is completed.</p> |
