US Patent 9764754 Push cart

A push cart, including: a frame, a rear wheel assembly, a front wheel assembly, a connection rod linkage. The frame includes an upper frame and a lower frame, and the upper frame is disposed on the lower frame. The rear wheel assembly is movably disposed on the lower frame or the upper frame. The front wheel assembly is disposed on the lower frame. The frame is connected to the rear wheel assembly via the connection rod linkage. The rotation of the upper frame or the lower frame drives the connection rod linkage to flatten the rear wheel assembly with the upper frame or the lower frame, or to unfold the rear wheel assembly.