Automatic pencil with function of avoiding core breaking and clamping

The utility model discloses an automatic pencil with a function of avoiding core breaking and clamping. The automatic pencil is characterized by comprising a core guide tube (6) and a core storage tube (17), wherein a left semi-opened ladder-shaped groove (27) and a right semi-opened ladder-shaped groove (28) are formed in the two sides of an outer profile body (24) of the core guide tube (6); the left semi-opened ladder-shaped groove (27) and the right semi-opened ladder-shaped groove (28) are formed in the two sides of the outer profile of the core storage tube (17); and the width of an inner groove opening (37) of the ladder-shaped groove is smaller than the diameter of a lead core (1). The utility model further provides a core conveying mechanism and a core locking mechanism as well as a rubber eraser (11) matched with a pencil cap (12), wherein a lining tube (10) is embedded in the center of the rubber eraser and provided with a central hole (34). The automatic pencil has the benefits as follows: the cor