Passive knee joint flexible power assisting device

The utility model relates to a passive knee joint flexible power assisting device which comprises a leg component which comprises a thigh component and a shank component, and the thigh component and the shank component are connected and supported through a connecting piece and an elastic piece and can rotate relatively. The contact ends of the thigh assembly and the shank assembly are contacted through an elastic piece. The thigh assembly and the shank assembly are connected with the two fixing assemblies in a one-to-one correspondence mode and are detachable, and the fixing assemblies serve as connecting and fixing pieces for wearing; an energy storage adjusting mechanism is detachably arranged on the thigh assembly and located on the inner side of the thigh assembly. The energy storage adjusting mechanism can manually change energy initially stored by the device. A manual adjustable energy storage adjusting mechanism is adopted to provide assistance energy, and the function of adjusting the initial energy o