Batch mixer

The utility model relates to a batch mixer, which belongs to the technical field of sample detection and comprises a machine table, a horizontal sample seat plate is rotatably connected in the machine table, and a control component for driving the sample seat plate to rotate is arranged outside the machine table; a plurality of groups of through holes are formed in the sample seat plate, a plurality of groups of placing cylinders are arranged on the sample seat plate, and openings of the placing cylinders are communicated with the through holes; the placing cylinder comprises a first sub-cylinder and a second sub-cylinder, the first sub-cylinder is connected with the sample seat plate, the second sub-cylinder is connected in the first sub-cylinder in a sliding manner, and one end, far away from the sample seat plate, of the first sub-cylinder is provided with an open hole for the second sub-cylinder to partially extend out; the sample seat plate is provided with a cover plate, and the cover plate is provided