Classification device and shot processing device

A classification device comprising:

• a sorter configured to sort a group of powder particles using an airflow;
• a duster configured to generate the airflow;
• a sensor configured to measure a measurement value related to a speed of the airflow;
• and
• a controller configured to perform wind speed control that controls the speed of the airflow so that the measurement value is maintained within a control range,
• wherein the controller determines whether or not an abnormal state, in which a plurality of measurement values measured by the sensor are out of the control range, is continuously maintained over a detection time period, and performs the wind speed control in response to it being determined that the abnormal state is continuously maintained over the detection time period, and
• wherein the controller measures an elapsed time that elapses from a time at which the wind speed control ends, and maintains stopping of the wind speed control until the elapsed time reaches a waiting time from the time at which the wind speed control ends.