US 12,012,139 B2
Folding cart with high load-bearing chassis structure
Yuanru Sun, Zhejiang (CN); and Jian He, Zhejiang (CN)
Assigned to ZHEJIANG JIANSHENG LEISURE PRODUCTS CO., LTD, Zhejiang (CN)
Filed by ZHEJIANG JIANSHENG LEISURE PRODUCTS CO., LTD, Zhejiang (CN)
Filed on May 31, 2021, as Appl. No. 17/334,825.
Application 17/334,825 is a continuation in part of application No. 17/137,367, filed on Dec. 30, 2020.
Application 17/137,367 is a continuation in part of application No. PCT/CN2020/116444, filed on Sep. 21, 2020.
Claims priority of application No. 201921755041.6 (CN), filed on Oct. 18, 2019.
Prior Publication US 2021/0284216 A1, Sep. 16, 2021
Int. Cl. B62B 3/02 (2006.01); B62B 5/06 (2006.01)
CPC B62B 3/02 (2013.01) [B62B 5/067 (2013.01); B62B 2205/02 (2013.01); B62B 2205/06 (2013.01); B62B 2205/26 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A folding cart with a high load-bearing chassis structure, comprising a frame body, the frame body comprises: a chassis, four lower hinge seats at four corners of the chassis, a front folding mechanism at a front of the chassis, a rear folding mechanism at a back of the chassis and two side-folding mechanisms on both sides of the chassis,
wherein each of the side-folding mechanisms comprises at least one X-shaped crossed hinge rod group, upper ends of both sides of each of the side-folding mechanisms are respectively hinged with two corresponding upper hinge seats, lower ends of both sides of each of the side-folding mechanisms are respectively hinged with two corresponding lower hinge seats;
the front folding mechanism comprises at least one X-shaped crossed hinge rod group, upper ends of both sides of the X-shaped crossed hinge rod group of the front folding mechanism are respectively hinged with two corresponding upper hinge seats, lower ends of both sides of the X-shaped crossed hinge rod group of the front folding mechanism are respectively hinged with two corresponding lower hinge seats;
the rear folding mechanism comprises at least one X-shaped crossed hinge rod group, upper ends of both sides of the X-shaped crossed hinge rod group of the rear folding mechanism are respectively hinged with two corresponding upper hinge seats, and lower ends of both sides of the X-shaped crossed hinge rod group of the rear folding mechanism are respectively hinged with two corresponding lower hinge seat;
the chassis comprises two X-shaped crossed hinge structures, inner ends of a left side and inner ends of a right side of the X-shaped crossed hinge structures are respectively hinged together with a first connector, a middle part of each of the side-folding mechanisms has a second connector, outer ends of each of the X-shaped crossed hinge structures are respectively and universally hinged with two corresponding lower hinge seats,
when the folding cart is transformed from an unfolded state to a folded state, the X-shaped crossed hinge structures are able to tilt and swing relative to the lower hinge seats, so as to promote the two X-shaped crossed hinge structures to transform from a horizontal state to a collapsed state, the first connectors and the second connectors are transformed from a buckled state to an unbuckled state;
each of the X-shaped crossed hinge structures comprises a first bottom rod and a second bottom rod assembly, the second bottom rod assembly comprises a bottom rod connecting seat hinged with a middle part of the first bottom rod and two second bottom rod bodies respectively provided at both ends of the bottom rod connecting seat.