PROBLEM TO BE SOLVED: To provide a knee joint which has a bending angle limited in a stance phase subject to floor reaction, because a maximum bending angle becomes smaller according to an increase in the floor reaction, which can prevent instability of prosthetic knee, and which enables a user to naturally ascend stairs.SOLUTION: A knee joint includes: a thigh-side member 10 a leg-side member 20 which is rotatably coupled to the thigh-side member 10 and a maximum bending angle adjusting means 30 for decreasing the maximum bending angle of the leg-side member 20 with respect to the thigh-side member 10 according to an increase in floor reaction and increasing the maximum bending angle according to a decrease in the floor reaction. Since the maximum bending angle becomes smaller according to the increase of the floor reaction, the bending angle is limited in a stance phase subject to the floor reaction, and the instability of prosthetic knee can be prevented. Extension moment is generated according to a transfer of body weight to the knee joint 1, and a stairs ascending motion can be assisted. Thus, a user can naturally ascend stairs.COPYRIGHT: (C)2013,JPO&INPIT【課題】自然な昇段を可能とする膝継手を提供する。【解決手段】大腿側部材10と、大腿側部材10に対して回動可能に連結された下腿側部材20と、大腿側部材10に対する下腿側部材20の最大屈曲角度を、床反力の増加に従い小さくし、床反力の減少に従い大きくする最大屈曲角度調整手段30とを備える。床反力の増加に従い最大屈曲角度が小さくなるので、床反力がかかる立脚期において屈曲角度が制限され、膝折れを防止できる。膝継手1に体重が移るに従い伸展モーメントが発生し、昇段を補助できる。これにより、自然な昇段が可能となる。【選択図】図1
