Dissolution tester easy for protection operation

The dissolution tester comprises a box body, the upper surface of the top of the box body is connected with a placing disc in a penetrating and sliding mode, the middle positions, away from any two side walls of the center, of the placing disc are connected with fixing mechanisms in a penetrating and sliding mode, and the fixing mechanisms comprise limiting rods; moving blocks are fixedly connected to the ends, away from the placing disc, of the two limiting rods, first springs are fixedly connected to the symmetrical positions of the sides, close to the limiting rods, of the two moving blocks, protruding blocks are fixedly connected to the middle positions of the upper surfaces of the tops of the two limiting rods, and moving rods are slidably connected to the ends, away from the limiting rods, of the two protruding blocks. By arranging the fixing mechanism, the placing disc can be stably placed on the box body through limiting and fixing of the limiting rod and the placing plate, so that the stirring qualit