Automatic stop method and device for can opener

An automatic stop device for a can opener, comprising a control module, a photo-interrupter, a grating wheel, a power supply module, a bearing drive module provided with a bearing, and a can opener blade, wherein:

• the control module is electrically connected to the power supply module, the bearing drive module and the photo-interrupter, the power supply module is electrically connected to the bearing drive module and the photo-interrupter, the grating wheel is disposed around the bearing, a moving track of the grating wheel passes through a photoelectric detection region of the photo-interrupter, and the bearing is fixedly connected to the can opener blade;
• the bearing drives the grating wheel to rotate, and the control module is configured to:
• start the can opener, acquire multiple rotation frequencies of the bearing within a first preset time, calculate a mean value of the multiple rotation frequencies, and regard the mean value as a first frequency, wherein the bearing is used for driving the can opener blade to rotate;
• acquire multiple rotation frequencies of the bearing within each second preset time after the first preset time, calculate a mean value of the multiple rotation frequencies, and regard the mean value as a second frequency;
• and
• determine whether or not a difference between the second frequency and the first frequency is greater than a preset value;
• if so, stop the can opener blade;
• or if not, acquire multiple rotation frequencies of the bearing within each second preset time after the first preset time, calculate the mean value of the multiple rotation frequencies, and regard the mean value as the second frequency.