# US 5,344,446 A · Teaching playback swing-phase controlled above-knee prosthesis > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,344,446 A - Document ID: US5344446A - Status: Granted - Kind: A - Application number: 07/867,505 - Filed: 1992-04-13 - Granted: 1994-09-06 - Earliest claimed: 1988-03-25 - Assignees: Kabushiki Kaisha Kobe Seiko Sho; Hyogo-ken Shakaifukushijigyodan - Inventors: Seishi Sawamura; Sakuya Nakajima; Kunio Amemori; Hidehisa Oku; Akio Nakagawa; Ichiro Kitayama; Hiromu Matsuda; Katsuhiko Yoshida; Masaru Takeda; Toshio Nakane; Shiro Horiguchi; Shigeru Yuki - Web page: https://patentgrep.com/patent/US5344446A ## CPC - A61F 2/68: Operating or control means - A61F 2/64: Knee joints - A61F 2/74: fluid {, i.e. hydraulic or pneumatic} - A61F 2/748: {Valve systems} - A61F 2002/6818: {for braking} - A61F 2002/704: {computer-controlled, e.g. robotic control} - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) ## Abstract A teaching playback swing-phase-controlled above-knee prosthesis comprises a thigh frame, a leg frame, an air cylinder interconnecting the thigh and leg frames and provided with adjusting means for adjusting the degree of opening the valve of the air cylinder to a plurality of degrees respectively for a plurality of walking speeds selected during trial walking, a mode selecting switch having positions respectively for setting degrees of opening of the valve of the air cylinder in a teaching mode and for a playback mode in which one of the degrees of opening is selected according to an actual walking speed, an opening detector for detecting the degree of opening of the valve of the air cylinder, an opening storage device for storing a plurality of set degrees of opening of the valve of the air cylinder, a phase detector for detecting swing phases and stance phases, walking speed detector for detecting an actual walking speed, and control unit for adjusting the degree of opening of the valve of the air cylinder to one of the set degrees of opening corresponding to the actual walking speed. The teaching playback swing-phase-controlled above-knee prosthesis is capable of automatically controlling the speed of swing motion of the leg frame according to the actual walking speed of the prosthesis wearer. ## Claims ### Claim 1 A teaching playback swing-phase-controlled above-knee prosthesis adapted for mounting to a thigh of a wearer, comprising: a thigh frame; a leg frame pivotally joined to the thigh frame via at least one knee joint pin, a cylinder interconnecting the thigh and leg frames; phase detecting means for detecting at least one of swing phases and stance phases of walking in a teaching mode and a playback mode; opening storage means configured to store a plurality of degrees of opening of an air valve of the cylinder set respectively for a plurality of walking speeds in response to the phase detecting means in the teaching mode; walking speed determining means for determining an actual walking speed during the playback mode on the basis of the lengths of at least one of said swing phases and stance phases detected by the phase detecting means; and control means responsive to the walking speed determining means for selecting one of the stored degrees of opening of the air valve of the cylinder during the playback mode. ### Claim 2 (depends on 1) The prosthesis of claim 1 wherein said control means further comprises means for comparing the at least one of swing phases and stance phases in the teaching mode with the at least one of swing phases and stance phases in the playback mode. ### Claim 3 (depends on 2) The prosthesis of claim 2 wherein said control means further comprise means for selecting one of the stored degrees of opening based on the comparison made by said comparing means. ### Claim 4 (depends on 3) The prosthesis of claim 3 wherein said opening storage means stores three degrees of opening of the air valve. ### Claim 5 (depends on 4) The prosthesis of claim 4 wherein said three degrees of opening S.sub.T are S.sub.SLOW, S.sub.MID and S.sub.FAST, and T is the period of at least one of swing phases and stance phases, wherein: S.sub.SLOW is selected when T.gtoreq.(T.sub.SLOW +T.sub.MID)/2, S.sub.MID is selected when (T.sub.MID +T.sub.FAST)/2.ltoreq.T<(T.sub.SLOW +T.sub.MID)/2, S.sub.FAST is selected when T<(T.sub.MID +T.sub.FAST)/2. ### Claim 6 (depends on 1) The prosthesis of claim 1 wherein said phase detecting means comprise a detector for detecting an angle between said leg frame and said thigh frame. ### Claim 7 (depends on 2) The prosthesis of claim 2 wherein said phase detecting means comprise a detector for detecting an angle between said leg frame and said thigh frame. ### Claim 8 (depends on 3) The prosthesis of claim 3 wherein said phase detecting means comprise a detector for detecting an angle between said leg frame and said thigh frame. ### Claim 9 (depends on 4) The prosthesis of claim 4 wherein said phase detecting means comprise a detector for detecting an angle between said leg frame and said thigh frame. ### Claim 10 (depends on 5) The prosthesis of claim 5 wherein said phase detecting means comprise a detector for detecting an angle between said leg frame and said thigh frame. ### Claim 11 (depends on 1) The prosthesis of claim 1 including a braking device.