Abstract: An artificial knee comprises first and second pivotally interconnected knee components and first and second interengaging brake components for locking the knee components together. The first and second brake components are associated respectively with the first and second knee components, respectively. The second brake component is made of a resiliently deformable material. The arrangement is such that, when the artificial knee is subjected to a first load condition, the brake components are substantially free to slide against one another, and when the artificial knee is under a second, higher load condition, the second brake component is resiliently deformed against the first brake component to lock the two brake components together, thereby locking the two knee components together.

Abstract: The invention relates to a device producing a stance flexion. This goal is achieved according to the invention by virtue of the fact that in the initial position of the multi-element joint system one element (joint element) can execute two movements with respect to the other elements (joint elements) connected to it, with at least one movement, after its initiation, at least predominantly blocking the other possible movement.

Abstract: A knee prosthesis has two pivotally interconnected members (10,11) carrying a locking device (17) and a first end a second axle (20,21). The first axle (20) forms a bearing axle for the locking device and the second axle (21) cooperates with the locking device for activation thereof. The second axle (21) is located at a distance behind the first axle (20) and is arranged to act upon the locking device in such a way that when the line of action (26) from a load on the knee prosthesis passes through the second axle (21) or between the first (20) and the second axle, said second axle will act upon the locking device to activate it, while when said line of action (26) passes through the first axle or in front of it the second axle (21) will be unloaded and the locking device (17) inactivated.

Abstract: The invention relates to a brake joint for a prosthesis, in particular, to a brake-action knee joint for a leg prosthesis. There is an upper joint part, a lower joint part, and a joint shaft for pivotally connecting the upper and lower joint parts. The joint shaft is connected to the lower joint part in a rotatably fixed manner and is designed as a brake shaft. The joint shaft is surrounded by a brake arrangement, which bears upon the joint shaft it and is arranged in a cylindrical recess, which, together with the joint shaft, forms an annular chamber in a clamping part forming a central joint part. The upper joint part is mounted to the clamping part in an articulated manner via a pivot pin in such a way that the upper joint part, when loaded, impacts on the clamping part and thus the brake arrangement and thereby exerts a braking action on the joint shaft.

Abstract: An artificial knee joint includes a hollow cylinder (5) in which a piston member (62) is disposed movably. The piston divides the cylinder (5) into upper and lower chambers (51, 52). The swing phase control member (8) has first and second channels (80, 81), a fulcrumed lever member (82) bridging the first and second channels (80, 81). The second channel (81) is communicated with the upper and lower chambers (51, 52). The first end of the lever member (82) extends into the first channel (80) for movement in response to an air pressure in the first channel (80). The second end of the lever member (82) has a first throttle valve unit (83) for regulating the air flow through the second channel (81) in response to a movement of the lever member (82). A pump unit (7) is associated operatively with the piston member (62) for pumping air from the ambient to the first channel (80) in response to a movement of the piston member (62).

Abstract: A computer controlled hydraulic resistance device for apparatus such as a prosthetic knee for above knee amputees, includes a two stage pilot operated solenoid valve connected to control the flow of hydraulic fluid to and from a hydraulic actuator which applies resistance to the prosthetic knee or other apparatus through a coupling. Hydraulic pressure is sensed on the high and low side of the actuator by a spring biased magnet and a magnetically actuated electronic sensor and is used by a micro-controller in a closed-loop manner to compensate automatically for variations in the device and in the hydraulic fluid viscosity. The device also has magnetically actuated electronic sensors which sense positions of the apparatus and feed back to the micro-controller for applying a predetermined resistance profile to the apparatus.

Abstract: A patient-weight-activated hydraulic knee joint in which flow between hydraulic chambers is controlled by a valve operated by hydraulic pressure and by a force transmission system which transmits the force of a patient's weight, such that the valve is only closed when the patient's weight acts on the knee joint. Closure of the valve locks the knee joint, so hence undesirable locking does not occur during the swing phase of the patient's gait. A damped hydraulic trip valve can also be provided to give improved operation of the knee joint.

Abstract: There is provided a prosthetic leg with an extension auxiliary mechanism 1100 capable of generating an extension torque only when an angle of bending of the knee is small. A knee joint 80 of a thigh prosthesis 170 is of a multi-axis structure, and a front and a rear link 130, 150 together with an upper thigh member 110 and a lower thigh member 120 constitutes a constrained chain. An extension auxiliary mechanism 1100 having a compression spring is supported between the lower thigh member 120 and the rear link 150. An extension torque generated by the extension auxiliary mechanism 1100 is determined by a product of a force caused by biasing of the compression spring and a distance from a line of action of the force to the center of rotation of the rear link 150. Here, at a stage where the bending angle of the knee exceeds, for example, 15 degrees, an axis of the compression spring is brought generally into alignment with a connecting portion 170O between the rear link 150 and the lower thigh member 120.

Abstract: A hydraulic cylinder control unit for gait control of a prosthetic limb which features two cylindrical tubes that are eccentric with respect to each other. The inner tube houses hydraulic fluid and the gap between the two tubes serves as a displacement chamber as a piston, mounted on a piston rod, moves through the fluid in the inner tube. When the outer tube is rotated about the inner tube, the gap between the tubes changes which either increases or decreases the flow allowed between the tubes. This changes the resistance which controls the rate of swing of an artificial limb. The resistance is easily adjustable by a simple rotation of the outer cylindrical tube. A floating sealed piston is additionally provided at the bottom of the inner tube. The sealed piston moves upwards or downwards depending on the balance of forces between the fluid force above the piston and the stored energy force below the sealed piston.

Abstract: A rotation damper for toggle joints prosthesis (1) that is arranged for swing phase control of the prosthesis, and incorporates a housing having at least one clamber (13) with a damping medium disposed therein is disclosed. The chamber is arranged so that the damping medium is displaced through a restriction (14a) with a swing motion of at least one pivot axle (6) in the prosthesis. The damping medium is a visco-elastic compound, having an ability to exert a bigger resistance at rapid motion processes as compared to slower processes.

Abstract: A prosthetic component with a pneumatic device for knee articulation formed of an upper part adapted to support a socket element for a stump of a thigh, and a lower part intended to receive a tube extended by an ankle and foot. The two parts are connected to each other by an assembly of pivoted links forming a deformable prism. Movement of the two parts between two stable positions of complete extension and flexure, about the variable axis of rotation defined by these connections, is controlled by a pneumatic cylinder having an upper chamber and a lower chamber separated by a piston and communicating with each other by an air duct with adjustable flow. In each of the stable positions, the pressure of air in the chambers is greater than 1 bar and is preferably between 4 and 7 bar.

Abstract: Paying attention to the mechanical play between the first and second support members for supporting opposite end portions of a knee axis and a brake block located between the support members, the present invention chiefly aims at removing the play in the direction of an axis of the knee axis in an effective and a reliable manner. In order to achieve this object, according to the present invention, a plurality of spacer members are inserted between each support member and the brake block such that the spacer members may slide on the mutual abutment surface. Each spacer member is of a ring type. The spacer members are fitted to and supported by the knee axis in a state that the spacer members are overlaid one upon another in the axial direction of the knee axis. In order to enhance the smooth sliding on the abutment surface, the spacer members are preferably made of resin material.

Abstract: The invention relates to a prosthesis comprising first and second prosthesis parts connected for mutual movement which are characterized by a locking element for locking respectively releasing the prosthesis parts relative to each other. The parts are preferably connected for mutual movement by an artificial joint comprising a first and a second joint part. The locking element is spring biased and co-acts in a locked position with a recess in one of the joint parts, whereby tilting of the locking element is bounded, and which in the released position is substantially freely tiltable. The prosthesis can be further provided with a pin for actively placing the locking element out of the active reach of the recess. One of the two prosthesis parts connected for mutual movement is formed with a cup so that the prosthesis can be fixed to the remaining part of an amputated extremity.

Abstract: An adaptive control system for an artificial limb has a piston and cylinder assembly for controlling knee joint flexion, an electronically driven motorised valve for varying the damping effect of the assembly, a proximity sensor for sensing knee flexion, and a processor circuit for mounting on the limb. The system also has a radio receiver connected to the processor circuit and an operator control unit for remote transmission of command signals to the receiver. In a teach mode, the system allows an operator to increment the valve opening by remote control to optimise operation of the limb, and to cause the processor circuit to record selected valve openings in conjunction with average step period values which are produced automatically by the system during use of the limb. Recording a new selected valve opening causes the processor circuit on the limb automatically to calculate a set of control data relating valve openings to walking speed ranges.

Abstract: The invention relates to a device producing a stance flexion. This goal is achieved according to the invention by virtue of the fact that in the initial position of the multi-element joint system one element (joint element) can execute two movements with respect to the other elements (joint elements) connected to it, with at least one movement, after its initiation, at least predominantly blocking the other possible movement.

Abstract: An artificial limb provides for positional relation between a first pin for rotatably connecting one end of an air cylinder device to a lower member and a second pin for rotatably connecting the other end of the air cylinder device to an upper member. The attaching position of the second pin is set to satisfy certain predetermined conditions when an artificial limb is in a completely extended state. The position of an air cylinder device (particularly, the attaching position of the second pin) is changed in conformity with a walking speed which is variable in phase such as normal walking, quick walking, and running with small steps. The artificial limb further comprises a pin position change capable of changing the position of a second pin rotatably connected to an upper member in conformity with variation of walking speed.

Abstract: A computer controlled hydraulic resistance device for apparatus such as a prosthetic knee for above knee amputees, includes a solenoid actuated valve connected to control the flow of hydraulic fluid to and from a hydraulic actuator which applies resistance to the prosthetic knee or other apparatus through a coupling. Hydraulic pressure is sensed on the high and low side of the actuator and is used by a micro-controller in a closed-loop manner to compensate automatically for variations in the device and in the hydraulic fluid viscosity. The device also senses the position of the apparatus and feedsback to the micro-controller for applying a predetermined resistance profile to the apparatus.

Abstract: A device for damping of the turning movement of a joint such as an artificial knee joint is built into a bearing bridge of a joint. The joint can be a seven pivot point joint with a shaft of one of the pivot points being provided with a gear-wheel. The damping device includes a hydraulic cylinder with a piston connected to the gear-wheel. Channels with chokes and back valves connect the two sides of the piston of the hydraulic cylinder whereby adjustable damping in several steps can be achieved. A compact design for a joint and damping cylinder is achieved.

Abstract: A test prosthesis comprising a thigh member (6), a lower leg member (7), a joint (4) connecting both members and a knee part (1) is provided. The knee part (1) is connected to the thigh member (6) or to the lower leg member (7), respectively, through a connection unit (8) allowing a relative movement of the connected members in a direction inclined with respect to the leg axis. This allows a relative adjustment of the position of the members, whereby a selection of the correct prosthesis for a thigh amputated person is easily possible by testing different members.

Abstract: A knee unit for an above-knee prosthetic leg includes a piston arrangement, a valve arrangement and a bladder arrangement for achieving swing and stance control of the prosthetic leg. For swing control the piston arrangement displaces a fluid through the valve arrangement to compress the bladder arrangement for storing the energy required to drive an extension cycle of the prosthetic leg and to provide bias and flexion resistance for the knee unit. For stance control the valve arrangement is such that when weight is applied to the heel of a prosthetic foot at various stages of the gait cycle of the prosthetic leg, the knee unit is permitted to flex or is prevented from flexing via compression of the bladder to provide stability during the various phases of the gait cycle.

Abstract: A prosthetic brake joint includes an upper joint portion, a lower joint portion, and a joint shaft which pivotably connects the two joint portions together. The joint shaft, designed as a brake shaft, is connected to the lower joint portion for fixed rotation with the lower joint portion. A brake bushing surrounds and rotates about the joint shaft and operates as a bearing. The brake bushing is connected to a clamping or support portion for fixed rotation with the clamping or support portion. The upper joint portion is mounted to the clamping or support portion in an articulated manner via a pivot axle. Under loading, the upper joint portion impacts the clamping or support portion and thus the brake bushing, and thereby exerts a braking force on the joint shaft. The brake bushing is surrounded by an annular brake chamber which is filled with an incompressible medium.

Abstract: An improved four-bar knee joint mechanism for use in knee disarticulation prosthesis is shown, including a coupler link forming a negative angle with the horizontal when said knee joint mechanism is in its stance position, an anterior link, a fixed link in a horizontal position when said knee joint is in the extended or stance position, and a posterior link, the dimensions of the links and the angle the coupler link makes with the horizontal being chosen to optimize the instant center of the mechanism.

Abstract: An artificial knee joint includes a shank formed with a pair of upwardly extending first lugs and a pair of radially extending second lugs, and a thigh support formed with a pair of downwardly extending third lugs which are connected pivotally to the first lugs. A connector has a first portion which extends between and which is mounted pivotally to the third lugs, a second portion which extends from the first portion and which extends between the first lugs, and a connecting portion formed at a junction of the first and second portions. A biasing unit on the shank biases the second portion of the connector upwardly. The connecting portion of the connector extends between and is connected pivotally to a spaced pair of pivot blocks on an upper end of an actuating member. The actuating member further has a lower end which extends between and which is connected pivotally to the second lugs.

Abstract: The invention relates to a hinge joint or swivel coupling in orthopaedic sthesis and ortheses, with an upper joint component (1), a lower joint component (2) and, if applicable, interposed control arms (9, 10) (hereinafter designated collectively as "hinge joint members") and a control element (4), that effectively engages both sides of a hinge joint member (1; 1, 2) (hereinafter "articulated joint member") each via one hinge point (7, 8) distanced from a pivot (3; 20, 21; 25, 26). To effect an improvement, the invention proposes that at least one of the above-mentioned hinge points (7, 8) is kinematically connected to at least one other hinge joint member (2; 9, 10; 9) via a mechanical geared coupling (11, 12, 13, 14; 15, 16, 17; 18, 24; 30, 31) and is arranged in such a way that it can change position in relation to its articulated joint member (1; 1, 2). FIG. 17.

Abstract: A brake-action knee joint for a leg prosthesis includes a closed displacer chamber which concentrically surrounds the joint pin over its circumference, at least partially, is preferably filled with hydraulic oil, and is arranged in the associated end of the central part of the joint. The joint pin is designed as a rotary piston and is connected in torsionally rigid fashion to the upper part of the joint. The joint pin divides the closed displacer chamber into an extension chamber and a flexion chamber, which are connected to one another by way of an oil line which can be completely or partially closed by a valve plunger.

Abstract: A prosthetic knee component for an above knee prosthesis having a frame member and a bracket member pivotally connected to the frame member, thereby creating a center of rotation for the knee component. The knee component further including a gait control unit pivotally positioned between the frame member and the bracket member by flanges extending from a rear portion of the bracket member. A flexion bumper is positioned through the frame member away from the center of rotation and is sufficiently compressible in a flexion phase of the knee component to provide controlled energy absorbing compliance under force exerted on the bumper by the rear flanges. The knee component further includes an optional running gait flexion limiter positioned on an interior surface of the frame member for limiting flexion and providing inertia to the lower leg component during a running gait.

Abstract: The invention relates to a device producing a stance flexion. This goal is achieved according to the invention by virtue of the fact that in the initial position of the multi-element joint system one element (joint element) can execute two movements with respect to the other elements (joint elements) connected to it, with at least one movement, after its initiation, at least predominantly blocking the other possible movement.

Abstract: Disclosed is an orthotic joint for an orthotic knee, hip or other similar brace that would eliminate the use of sidebars and would automatically lock upon full extension. The locking mechanism could also be fixed in an unlocked position if desired. Instead of a lock, one of a series of barrels of different diameters could be used as stops. The diameter of the barrel would determine the degree of stop. The locking mechanism or barrel would be vacuum-formed into the knee section of a typical custom-made knee orthosis or knee ankle foot orthosis. A round disk with a range-of-motion cutout and a locking hole is positioned between the thigh and calf portions of the brace. In one embodiment, a plunger mounted through the locking mechanism would roll on a cutout in the disk until reaching the tapered hole and then be forced in by a spring to lock the joint. Barrels, instead of a plunger, could be used if a stop, instead of lock, is desired. The locking mechanism could be unlocked by pulling or turning the plunger.

Abstract: This invention relates to an above knee prosthesis which employs a hydraulic damper to passively regulate the angular velocity or rotation of the artificial knee joint. A programmed microprocessor recognizes common gait patterns from information received from bending moment strain and knee angle sensors on the prosthesis. The microprocessor, under the control of a rule-based program, reacts at various transition points in the gait by activating a motor which in turn adjusts a valve assembly in the damper. The valve assembly is capable of variably and separately damping the knee joint motion in each of flexion and extension at the same time. Gait is improved because of the improved extent of control of knee action. In addition, distinct routines such as stair descending and sitting down can also be practised.

Abstract: The invention relates to a device for mutual pivoting connection of parts of an orthopaedic apparatus, such as in particular a knee prosthesis for leg amputees, comprising a kinematic multiple linkage system with at least four rods, adjoining rods of which have a common pivot axis and the pivot axes extend substantially mutually parallel.

Abstract: A knee brace for aiding in rehabilitation of damaged leg muscles includes upper and lower housings normally pivotable one relative to the other about the knee joint axis of a patient. The upper housing is attachable to the thigh of the patient above the knee joint while the lower housing is secured to a stirrup which extends downwardly along the patient's leg and is attached to the patient's shoe. An actuation rod is carried within the lower housing and is coupled to a cable. The upper and lower housings carry cooperative clutch/brake elements which normally are disengaged to permit relative movement between the upper and lower housings. When the cable is extended the clutch/brake elements engage and lock the housings together. A heel strike mechanism fastened to the stirrup and the heel of the shoe is connected to the cable to selectively extend the cable and lock the brace in substantially any position when the patient places weight on the heel.

Abstract: A controlled-brake orthosis for providing controlled limb movement includes a stimulator for stimulating an individual's leg muscles which causes the legs to move. An orthosis worn on the legs to support the legs include lower links rotatably coupled to upper links with lower rotatable joints. Brackets are rotatably coupled to the upper links with upper rotatable joints. The joints are located adjacent to the hip and knee joints of the individual and brakes are coupled to the joints for controlling the rotation of the joints. By controlling the stimulator and brakes with a computer, movement of the legs can be controlled to produce walking.

Abstract: The present invention is intended to provide a teaching playback swing-phase-controlled above knee prosthesis which enables an external data setting to set the mechanism of the teaching playback swing-phase-controlled above knee prosthesis for conditions that enable the mechanism to operate for motions according to a walking speed. The teaching playback swing-phase-controlled above knee prosthesis includes a structural body having a thigh frame and a leg frame pivotally joined to the thigh frame for swing motion relative to the thigh frame, an air cylinder having a cylinder body, a piston axially slidably fitted in the cylinder body and provided with a valve, and a piston rod having one end fixed to the piston and the other end pivotally joined to the thigh frame, and a stepping motor for adjusting the opening of the valve of the cylinder.

Abstract: A prosthetic leg has a pivotal knee joint and a hydraulic fluid control unit connected to provide variable forces which dampen flexion and extension of the knee and also bias the leg to its extended position. The unit includes an aluminum housing lined with an axially adjustable sleeve and control bushing defining a cylindrical operating chamber which receives a piston mounted on a tubular piston rod. The housing and operating chamber receive hydraulic fluid or oil which flows during movement of the piston through fluid control ports, channels and adjustable gaps defined by the sleeve and bushing for damping the movement of the rod. The piston rod encloses a preferably sealed gas pressurized flexible bladder which forms an oil accumulator during inward movement of the piston rod into a displacement chamber and also produces variable forces for moving the piston rod outwardly to its extended position.

Abstract: A prosthetic leg has a pivotal knee joint and a hydraulic fluid control unit connected to provide variable forces which dampen flexion and extension of the knee and also bias the leg to its extended position. The unit includes an aluminum housing lined with an axially adjustable sleeve and control bushing defining a cylindrical operating chamber which receives a piston mounted on a tubular piston rod. The housing and operating chamber receive hydraulic fluid or oil which flows during movement of the piston through fluid control ports, channels and adjustable gaps defined by the sleeve and bushing for damping the movement of the rod. The piston rod encloses a gas filled flexible bladder which forms an oil accumulator during inward movement of the piston rod into a displacement chamber and also produces variable forces for moving the piston rod outwardly to its extended position.

Abstract: In an artificial leg for a person having an upper thigh cut and a knee joint lost, a cylinder disposed between upper and lower leg members, which are coupled through a pivotable joint, for controlling bending and straightening of the joint by an air cushion for convenience of walking. The cylinder includes a cylindrical sleeve closed at both ends and a piston having a piston rod and sliding in the sleeve, and has its structure improved by using as a cushion one of two inner cavities separated by the piston, which encloses the piston rod, thereby buffering butting between the upper and lower leg members to remove unpleasant shock resulting at the end of straightening the joint.

Abstract: An artificial knee having a dual flexion action during locomotion is disclosed. The knee comprises a femur part and a tibia part capable of rolling over each other in two different ways depending on whether or not the artificial leg is loaded. Pressure exerted on a cam surface of the femur part flattens the curvature of the cam surface, limiting the angle of rotation of the artificial knee when the knee is loaded. The parts are connected by elastic ties which are fixedly connected to the femur part and movably connected to the tibia part. When the knee is loaded, depending arms from the femur part contact the movable tibia connection and increase the elongation of the elastic ties, thereby additionally resisting rotation.

Abstract: This invention relates to an above knee prosthesis which employs a hydraulic damper to passively regulate the angular velocity or rotation of the artificial knee joint. A programmed microprocessor recognizes common gait patterns from information received from bending moment strain and knee angle sensors on the prosthesis. The microprocessor, under the control of a rule-based program, reacts at various transition points in the gait by activating a motor which in turn adjusts a valve assembly in the damper. The valve assembly is capable of variably and separately damping the knee joint motion in each of flexion and extension at the same time. Gait is improved because of the improved extent of control of knee action. In addition, distinct routines such as stair descending and sitting down can also be practiced.

Abstract: An artificial leg has a femoral member (1); a lower-leg member (2) articulated to the femoral member about a knee joint axis (3') and adapted for connection to a prosthetic foot; and a hydraulic device (4) for controlling the knee joint functions of the artificial leg. The hydraulic device comprises a cylinder member (4a) which is articulated to the lower-leg member, and a piston rod (4b) which is articulated to the femoral member. The hydraulic device (4) is operated by an operating rod (11). The lower-leg member consists of an upper part (2a) which is articulated to the femoral member (1) and supports the hydraulic device (4) whose cylinder member (4a) is articulated to the upper part, and a lower part (2b) which is adapted for connection to the prosthetic foot and to which the operating rod (11) is connected. The upper part (2a) is articulated to the lower part (2b) about a pivot pin (13) located in front of the knee joint axis (3') to which it is parallel, to be pivoted relative to the lower member.

Abstract: An artificial leg includes a knee mechanism having means for restricting knee flexing movement during the stance phase of the walking cycle. The restricting means includes a piston and cylinder assembly so coupled in the mechanism that the piston is movable in the cylinder with knee flexion and extension. The knee mechanism includes two chassis parts arranged to move relatively to each other when an axial load is applied to the limb. One end of the piston and cylinder assembly is connected to one of the chassis parts while the other chassis part engages a control member coupled to a valve inside the piston and cylinder assembly so that the valve is operated in response to relative load-dependent movements of the chassis parts in order to restrict the flow of fluid and thereby create resistance to knee flexion during the stance phase. The chassis parts are connected together by an anterior pivot joint and are resiliently moveable relative to each other according to applied load.

Abstract: A device has a valve (21) activated by hydraulic fluid in opposition to a resilient restoring element (27) and blocking off an outlet in the bottom of a cylinder ( 3 ) when the fluid, responsive to being compressed by a piston (5), exerts a specified pressure subsequent to an involuntary movement on the part of a femoral amputee wearing the device so as to correct the gait of the amputee.

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

Abstract: An artificial knee-joint provided with linkage mechanisms, where a thigh part and a lower-leg part are mutually connected by tow base linkage arms, each of which is pivotally connected at respective ends with both the lower-leg part and the thigh part, wherein the pivotal attachment points of the lower-leg part are disposed in moveable attachment elements which mutually coact in a manner such that the knee-joint will automatically either adopt a substantially locked or a moveable position, depending on the direction of the load acting on the knee-joint. The first attachment element is pivotally connected to the two base linkage arms extending from the thigh part and has three pivot points, whereas the second attachment element has two pivot points. The back base linkage arm extending from the thigh part is pivotally connected to both attachment elements. The second attachment element is provided with a lock-stop device which limits movement of the attachment element.

Abstract: A novel form of crutch is provided which can be used, particularly by paraplegics, to move between sitting and standing positions. The crutch includes a unique foot mechanism which gives added stability to the user of a pair of the crutches during such sitting/standing transitions, and which can be retracted so as to avoid interference with normal crutch-aided walking. A set of such powered crutches, incorporating both power extension/retraction and power foot adjustment, are capable of extended powered operation with on-board electrical power, and use power only for adjustment and are self-locking into adjusted positions. The power assist of the crutches are controllable from switches strategically located by the crutch handles so the user can manipulate the control switches without releasing his/her hold on the crutch handles. Also disclosed is a unique method of assisting disabled persons, using such crutches, to move between seated and standing positions without further assistance.

Abstract: An articulated tang in clevis joint for incorporation in newly manufactured conventional strap-on orthotic knee devices or for replacing such joints in conventional strap-on orthotic knee devices. The instant tang in clevis joint allows the user the freedom to extend and bend the knee normally when no load (weight) is applied to the knee and to automatically lock the knee when the user transfers weight (load) to the knee, thus preventing a damaged knee from bending uncontrollably when weight (load) is applied to the knee.The tang in clevis joint of the present invention includes first and second clevis plates, a tang assembly and a spacer plate sandwiched and secured between the clevis plates. Each clevis plate includes a bevelled serrated upper section. A bevelled shoe is secured to the tang in close proximity to the bevelled serrated upper section of the clevis plates.

Abstract: A robotic knee for mounting on an upper leg stump of an allows movement from a standing position to a normal walking position and then to a kneeling position and return to a standing position. A mounting plate receives the upper leg stump of an amputee. The knee includes a housing having a drive motor which can be rotated in one direction to bend the knee and then reversed to straighten the knee. The drive motor turns a worm gear which engages a main drive gear. A pair of extension pulleys is mounted on a main drive gear shaft attached to the main drive gear. A pair of extension cables is attached at a first end to the extension pulleys and wrapped thereon. A second end of the extension cables is attached to a front portion of a mounting plate. A pair of flexion pulleys is also attached to the main drive gear. A pair of flexion cables is attached at a first end to the flexion pulleys and wrapped thereon. A second end of the flexion cables is attached to a rear portion of the mounting plate.

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 gait selecting switch having positions respectively for setting degrees of opening of the valve of the air cylinder in a teaching mode and for 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 acutal walking speed, and control unit for adjusting the degree of opening of the valve of the air cylinder in

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 degreess of opening of the valve of the air cylinder, a phase detector for detecing 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

Abstract: A prosthetic leg has a pivotal knee joint and a hydraulic fluid control unit connected to provide variable forces which dampen flexion and extension of the knee and also bias the leg to its extended position. The unit includes an aluminum housing lined with an axially adjustable sleeve and control bushing defining a cylindrical chamber which receives a piston mounted on a tubular piston rod. The housing and chamber receive hydraulic fluid or oil which flows during movement of the piston through fluid control ports, channel and adjustable gaps defined by the sleeve and bushing for damping the movement of the rod. The piston rod encloses a gas filled flexible bladder which forms an oil accumulator during inward movement of the piston rod and also produces variable forces for moving the piston rod outwardly to its extended position. The housing confines a gap defining ring which compensates for changes in oil viscosity with heat.

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.