Roll shaft mixer for powder mixing

The utility model discloses a roll shaft mixer for powder mixing, relates to the technical field of powder mixing equipment, and aims to solve the problem that a sample mixing bottle is easy to fall off through a simple structure. The sample mixing device comprises a base, at least two roll shafts which are in transmission connection with each other are arranged on the base, a sample mixing bottle is placed between the adjacent roll shafts, the distance between the adjacent roll shafts is smaller than the diameter of the sample mixing bottle, a driving device is fixedly arranged in the base or on one side of the base, and the driving device is in transmission connection with one roll shaft and used for driving all the roll shafts to rotate. The upper end of the base is also provided with two baffle plates which can be fixed in position, and the two baffle plates are respectively positioned on two outer sides of all the roll shafts and are used for blocking a path from which the sample mixing bottle falls to t