Mechanical lock with triple anti-theft function

The utility model relates to the field of locksets and particularly relates to a mechanical lock with a triple anti-theft function. The mechanical lock comprises a lock shell, a shifting tail and a lock liner, wherein a lock liner hole and a shifting tail mounting part are arranged on the lock shell; a key hole is formed in the lock liner; a plurality of arc-shaped grooves are formed in the inner side wall of the lock liner hole; two rows of lock pin sliding grooves which are mutually symmetrical and mutually penetrate through the key hole are formed in two sides of the key hole of the lock liner; the mechanical lock also comprises lock pins which are mounted in the lock pin sliding grooves; transverse tongues are arranged at the middle parts of the lock pins; a pair of convex ribs are arranged at the tail of the lock liner; symmetrically-arranged circular bosses are arranged at two ends of the shifting tail in a protruding manner; at least two pairs of symmetrically-arranged clamping slots formed by extending inwards along the peripheral edges of the circular bosses are arranged on the circular bosses; the two pairs of clamping slots are selectively to be in mutual match with the pair of convex ribs at the tail of the lock liner. By virtue of the mechanical lock, the problems of various parts, complexity in assembly and difficulty in processing of parts of a conventional mechanical lock can be solved; the inner structure is simplified; the mechanical lock has the triple protection function; the safety is improved.