Follow-up air supplement device

The utility model relates to a follow-up air supplement device which is applied to a laboratory, an air exhaust cabinet communicated with the outside is arranged in the laboratory, the air exhaust cabinet is provided with an air exhaust adjusting valve used for air exhaust, and the air exhaust cabinet is provided with a movable sliding door which is convenient for experiment operation and is used for adjusting the opening height; the follow-up air supplement device comprises a sensing element, an air supplement machine and an air supplement pipeline, and the follow-up air supplement device is arranged corresponding to the exhaust cabinet; the sensing element is arranged corresponding to the movable sliding door and is used for sensing the height of the movable sliding door; the air supplement machine is communicated with the interior of the laboratory through an air supplement pipeline and is used for supplementing air for the exhaust cabinet and the laboratory; the sensing element is in signal connection wit