Knee joint protection device

The invention belongs to the field of knee joint protection devices, in particular to a knee joint protection device. The knee joint protection device comprises a shin plate, a femoral plate, a bottomplate, a rack A, a spring A, a shaft A, a candan universal joint, a shaft B, an internal thread bushing, a spring J, an elastic rod, a sliding block C and a spring K, wherein the shaft B is connectedwith the shaft A through the candan universal joint. In the knee joint protection device disclosed by the invention, when the foot is put down, through the shin plate and the femoral plate, which aremutually hinged, by use of a transmission structure in the shin plate, energy is released so as to form an effective offset for body weight which needs to be borne by an injured knee joint, small body weight can reduce further injury to the injured knee joint, and the knee joint is effectively protected. In a foot raising process, the transmission structure in the shin plate can store energy again so as to make a preparati