Teaching playback swing-phase-controlled above-knee prosthesis

• US 5,062,856 A
• Filed: 03/23/1989
• Issued: 11/05/1991
• Est. Priority Date: 03/25/1988
• Status: Expired due to Term

• Current Assignee: Klaus Schmidt
• Original Assignee: Klaus Schmidt
• Inventors: Horiguchi, Shiro, Yuki, Shigeru, Nakagawa, Akio, Nakane, Toshio, Yoshida, Katsuhiko, Matsuda, Hiromu, Takeda, Masaru, Kitayama, Ichiro, Amemori, Kunio, Sawamura, Seishi, Nakajima, Sakuya, Oku, Hidehisa
• Primary Examiner(s): Shay, Randy Citrin
• Assistant Examiner(s): Willse, David H.
• Application Number:
  US07/327,894
• Time in Patent Office: 957 Days
• Field of Search: 623/27-46, 623/24-25
• US Class Current: 623/24
• CPC Class Codes: A61F 2/64 Knee joints
• CPC Class Codes: A61F 2/68 Operating or control means
• CPC Class Codes: A61F 2/74 fluid , i.e. hydraulic or pneumatic
• CPC Class Codes: A61F 2/748 Valve systems
• CPC Class Codes: A61F 2002/6818 for braking
• CPC Class Codes: A61F 2002/704 computer-controlled, e.g. robotic control

Abstract

A teaching playback swing-phase-controlled above-knee prosthesis has 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 has 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 detects the degree of opening of the valve of the air cylinder. An opening storage device for stores a plurality of set degrees of opening of the valve of the air cylinder. A phase detector detects swing phases and stance phases, walking speed detector determines an actual walking speed, and control unit adjusts 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

1. A teaching playback swing-phase-controlled above-knee prosthesis 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, said cylinder being provided with upper and lower chambers, an air valve and means for adjusting the degree of opening of the air valve of the cylinder to a plurality of values for a plurality of walking speeds which may be selected during trial walking in a teaching mode of operation;

mode selecting means having a plurality of positions including positions which may be selected in the teaching mode for setting degrees of opening of the air valve of the cylinder for the plurality of walking speeds and a position to be selected for a playback mode;

opening detecting means for detecting a degree of opening of the air valve of the cylinder during the teaching mode;

opening storage means for storing a plurality of degrees of opening of the air valve of the cylinder set respectively for the plurality of walking speeds in the teaching mode;

phase detecting means for detecting swing phases and stance phases of walking int h teaching mode and the playback mode and comprising a detector capable of detecting an angle between said leg and thigh frames;

walking speed determining means for determining an actual walking speed during the playback mode on the basis of the lengths of said swing phases and stance phases detected by the phase detecting means;

control means for adjusting the degree of opening of the air valve of the cylinder during the playback mode to one of said values of opening corresponding to the actual walking speed determined by the walking speed determining means; and

a braking device for braking a drop-off of said leg frame, said braking device comprising;

a brake disk and a movable brake shoe respectively mounted to alternate ones of said thigh and leg frames;

resilient means for biasing the brake shoe away from the brake disk;

a pneumatic actuator having a hermetic chamber and operatively connected to the brake shoe;

an air passage connecting the upper chamber of said air cylinder to the hermetic chamber of the pneumatic actuator and provided with a check valve;

an air passage connecting the hermetic chamber of the pneumatic actuator to the lower chamber of said air cylinder and provided with a check valve and a metering valve; and

an air passage connecting upper and lower chambers of said air cylinder and provided with a check valve and a metering valve.

2. A teaching playback swing-phase-controlled above-knee prosthesis according to claim 1 wherein said pneumatic actuator comprises a rubber tube capable of diminishing in length as the pressure therein increases.