Patent ID: 8201672

Claim:
An enhanced structure for base with roller and belt of hardshell zipper case, comprising: a hardshell zipper case main body, designed as a monolithic piece, further comprising a plurality of roller housing trenches, a belt housing trench and at least an auxiliary wheel trench, said roller housing trenches and said belt housing trench being located respectively at a main body bottom of said hardshell zipper case main body, an auxiliary wheel set being placed inside said auxiliary wheel trench, located at said main body bottom, outer rim of said auxiliary wheel set being convex above surface of back of main body; a plurality of hidden roller units, fastened to inside of said roller housing trenches, said auxiliary wheel set placed inside auxiliary wheel trench being located between said hidden roller units and said main body back, each said hidden roller unit having a roller exposed above surface of said main body bottom when moving, and hidden below surface of said main body bottom when parking; a retractable belt unit, fastened to inside of said belt housing trench; a hardshell lid; and an expanding unit, said expanding unit being connected between said hardshell zipper case main body and said hardshell lid, further comprising an expanding zipper and an expanding part.