Automatic protector

The utility model relates to an automatic protector, which belongs to the protection technical field of over-current of electricity and electric circuits. The technical problem that if a fuse is fused to be broken, the replacement of the fuse is operated manually in general is solved. The upper part of an insulating plastic box is provided with a spring compressing device and an insulating washer-protecting sheet group is connected with the spring compressing device. The insulating washer-protecting sheet group is contacted with supporting wire connection plates on the bottom. When the protecting sheet is fused to be broken because of over-current, one of the protecting sheet is fell off automatically. Under the action of the spring, the other protecting sheet is pressed on the two supporting wire connection plates automatically and thus the purpose of power on can be achieved. The utility model has the advantages of no manual change, simplicity and safety.