摘要 |
In a vacuum pressure control system, the vacuum pressure in a reaction chamber 10 is measured by vacuum pressure sensors 14 and 15 (S22), the measured value is changed at a set vacuum pressure changing speed commanded from the exterior or determined and stored in advance in a controller of the system (S24). The changed value is sequentially generated as an internal command. In response to the sequentially generated internal commands, a desired value of the feedback control is changed in sequence (S26), so that the feedback control is executed as follow-up control (S27). Accordingly, the vacuum pressure in the reaction chamber 10 can be uniformly changed to a desired vacuum at a set vacuum pressure changing speed. |