US Patent 9974388 Portable folding chair

The folding chair comprises a group of foot pipes, a group of seat frame pipes, a group of rotating connection pipes, a group of locking pipes and fabric. The group of foot pipes comprises a left and a right foot pipes. Armrest fixing pieces are fixedly installed on the upper ends of the foot pipes. A limiting piece is fixed in the middle of the foot pipes. A sliding piece is sleeved below the limiting piece. The upper ends of the four rotating pipes are rotatably connected with the seat frame pipes through a seat frame rotating piece; the other end of the four rotating pipes is rotatably connected with another linkage pipe of the four rotating pipes through a rotating piece fixed thereto; the rotating pipes are symmetrically arranged.