Stroller frame structure

A stroller frame structure, comprising at least:

• a front wheel rack coupling with front wheels of a stroller;
• a rear wheel rack coupling with rear wheels of the stroller and also pivotally coupling with a first linkage assembly and a coupling dock between two ends thereof, the first linkage assembly having a free end pivotally coupling with the front wheel rack so that the front wheel rack and the rear wheel rack are movable relative to each other;
• a handle tube for moving the stroller pivotally coupled with a connection element between two ends thereof to serve as an armrest of the stroller, the armrest having one end pivotally coupled with the front wheel rack and the rear wheel rack, the handle tube being latchable on the coupling dock to form a releasable interlocking condition among the rear wheel rack, the armrest and the handle tube;
• and
• a second linkage assembly coupling with the handle tube and the first linkage assembly to drive the first linkage assembly when a lower end of the handle tube is moved to move the front wheel rack and the rear wheel rack close to each other in the middle for folding or extending the front wheel rack and the rear wheel rack,
• wherein the first linkage assembly includes a front seat rack bar and a rear seat rack bar, one end of the front seat rack bar and the rear seat rack bar being pivotally coupled with a pivot coupler, the front seat rack bar being pivotally coupled with the front wheel rack, the rear seat rack bar being pivotally coupled with the rear wheel rack, and the front seat rack bar and the rear seat rack bar forming a straight line when extended, and forming a V-shape when driven by the second linkage assembly and folded towards each other.