Horseshoe-shaped lock

An anti-theft lock, comprising:

• a lock pin provided with a retaining groove and configured to realize unlocking or locking through movement of the lock pin;
• a tongue configured to be able to enter the retaining groove to stop the movement of the lock pin or move out of the retaining groove to release the lock pin to allow the lock pin to move, a driving hole being formed in the tongue and arranged with a stopper;
• and
• a tongue driving member configured to convert a rotational driving force of the motor into a driving force allowing the tongue to move out of the retaining groove, one end of the tongue driving member being connected to an output shaft of a motor in such a way that the tongue driving member is rotated with the motor, and another end of the tongue driving member being formed as a projection in such a way that when the tongue driving member is rotated, the projection is rotated along a circular trace taking an eccentric distance as a radius thereof,
• wherein:
• the projection extends into the driving hole and is configured to rotate against the stopper so as to drive the tongue to move in a direction of moving out of the retaining groove,
• when the projection continues to rotate and then goes beyond the stopper, the tongue loses a force allowing the tongue to move out of the retaining groove, and
• the driving hole is b-shaped through which an unlocking and a locking of the lock are realized.