Patent ID: 7188853

Claim:
A tricycle comprising: a frame having a frame body and a front fork fixed to a front section of said frame body; a seat cushion fixedly mounted on said frame body; a front wheel rotatably mounted to said front fork; a transmission mechanism including a crank set having two cranks and rotatably mounted to said frame, two pedals rotatably mounted respectively on said two cranks, a first chain gear fixedly mounted on said crank set, a second chain gear mounted on said front wheel, and a chain running on said first and second chain gears; a parallel four-bar linkage having a front bar, a rear bar, and two side bars each pivotally connected respectively with said front and rear bars, said front and rear bars being parallel to each other, said side bars being parallel to each other, said rear bar being fixedly mounted at a rear section of said frame body, a distance between said front bar and said front wheel being smaller than that between said rear bar and said front wheel, an elevation of said front bar being larger than that of said rear bar; two handlebars fixedly mounted respectively on said linkage and located respectively beside bilateral sides of said seat cushion; and two rear wheels rotatably mounted on said two side bars; wherein said frame body comprises a first strut and a second strut, said second strut being welded with said first strut and leaning backward and abutting a rear end of said first strut; said front fork being fixedly welded to a front end of said first strut; said seat cushion being fixedly mounted on said first strut; said crank set being rotatably mounted at the front end of said first strut; said rear bar being fixedly mounted at the rear end of said first strut; and a back cushion being mounted on said second strut.