Dry mixing device for preparing blended fertilizer

The utility model belongs to the field of mixed fertilizer mixing, and particularly relates to a dry mixing device for preparing a mixed fertilizer, which comprises a shell, a clamping block and a smashing box, a second smashing gear is arranged in the smashing box, and a rotating shaft is movably connected in the second smashing gear. A first smashing gear is movably connected to one side of the second smashing gear, a protective sleeve is fixedly connected to the interior of the first smashing gear, a transmission shaft is movably connected to the interior of the protective sleeve, a user pours a mixed material into the feeding opening, the mixed material falls onto the two smashing gears, the user starts a servo motor, and the servo motor drives the first smashing gear to rotate; according to the present invention, the mixing device is arranged in the crushing box, the transmission shaft is driven to rotate, the first crushing gear is driven to rotate, the second crushing gear is driven to rotate on the ro