Abstract: The service characteristics of a prosthesis shaft for a limb stump projecting from a pivotal articulation of a patient are determined by first fitting the shaft while engaged over the limb stump into a holder pivotal about a holder axis and then aligning the holder axis so that it generally traverses the articulation. The shaft and holder are then moved by the stump pivotally about the axis to establish extreme positions of the holder that cause discomfort to the patient. Movement within the extreme positions is established as an actual-value range and compared with a desired-value range. Then the fit of the shaft on the stump is adjusted and the first three steps are repeated until the actual-value range generally corresponds to the desired-value range. Normally the holder is pivotal about two generally perpendicular and coplanar holder axes and the intersection of the axes being set generally at the articulation.

Abstract: A planetary friction transmission, especially for miniature application as in prosthetic joints and the like, has cylindrical periphery planet wheels pressed by a stationary ring against a conical portion of the drive shaft, the ring being axially shiftable relative to the shaft and on a support. The planet carrier is connected to the planet wheels by pins which extend into the holes of the planet wheels with play.

Abstract: An artificial hand has its finger gripper swingable about an axis which includes an angle of 30.degree. to 70.degree. with a plane normal to axis of a prosthesis connector and its fingers inclined at an acute angle to the finger carrier to provide a more natural orientation of the hand for picking up objects at pick-up surfaces located above a support surface for the object.

Abstract: A prosthesis drive, especially for a hand prosthesis, can rapidly approach the grippers until resistance is sensed and then apply an increased force to the object. For this purpose, two electric motors drive selectively the respective planetary gearing in an arrangement in which the planet wheels of the two gearings engage a common gear between the sun and ring gear of one planetary gearing or the sun and ring gear of the other planetary gearing, the gearings being coaxial with one another and with the motors. A circuit responding to an increase in the current of the high speed motor above a threshold value is provided to control the switchover.

Abstract: A control valve for controlling the flow of a liquid, especially liquid of hydraulic damping unit with a hydraulic piston-and-cylinder arrangement, has a pressure chamber defined by lamellae extending along generatrices of a cylindrical housing wall and an end wall juxtaposed with this cylindrical wall. Since the lamellae are flexible, when there is a pressure increase in the chamber, the lamellae are deflected outwardly to reduce the free cross section of the throttle gap.

Abstract: A double-acting hydraulic piston-and-cylinder unit adapted to constitute a damper for movements in a human joint prosthesis has a boot sealingly connected to the cylinder and the piston rod to receive the hydraulic fluid under pressure as the hydraulic fluid is displaced from one or the other of two cylinder chambers upon displacement of the piston rod. The boot has a conically widening region or segment sealingly secured to the rod and adjoining the cylindrical segment of the boot surrounding the cylinder in a transition segment formed as an outwardly convex bulge and designed to ensure that initial inward movement of the piston rod will give rise to a plate membrane deformation of the elastic boot while only further displacement will result in a rolling action of the membrane. This ensures a generally cylindrical uniform configuration of the boot in all positions of the rod as is essential for effective use in a prosthesis.

Abstract: A rotary joint, especially for a prosthesis, e.g. to allow a user to assume the lotus position, as a pair of relatively rotating parts including an outer part and an inner part braced at coaxial bosses by tapered rollers forming a play-eliminating tapered roller bearing. An inclined roller bearing is provided between outer peripheries of disk portions of these parts. A housing enclosing the parts contains a locking device in which a locking element is spring biased to engage the parts with teeth of the locking element engaging in teeth of the two parts. A push-button can be depressed to retract the locking element and permit relative rotation.

Abstract: This hand is provided with two clamping jaws (1,2) movable toward or respectively apart from each other, each of which is mounted in each case to a hinge quadrangle (3, 4). At each clamping jaw (1, 2) there is supported a gripping plate (8, 9) tiltable around an axis (5, 6) vertical to the jaw axis. The two hinge quadrangles (3, 4) can be rotatably supported jointly by an axis running parallel to the hinge axes of the hinge quadrangles (3, 4), however, also the two hinge quadrangles can be jointly tiltable around one axis, which runs vertical to the hinge axes (FIG. 3).

Abstract: A swivel joint for a leg prosthesis has its relatively rotatable members urged into a neutral position by a multiple-disk compound axial compression spring bearing upon balls which ride along inclined ramps upon relative rotation of the members.

Abstract: The artificial wrist serves to connect an arm prosthesis shaft to an implement and comprises distal retaining means, a proximal retaining member adapted to extend into said prosthesis shaft and formed with first and second engaging surfaces, locking means interlocking with said distal retaining means and said first engaging surface to hold said distal retaining means and said proximal retaining member axially together, a sliding surface bearing adapted to rotatably connect an implement to said distal retaining means, and rotatable coupling means which engage said second engaging surface and are adapted to engage said prothesis shaft.

Abstract: An epicyclic transmission between a stationary member and a rotatable section of a prosthesis comprises a fixed ring gear secured to the stationary member, a driven ring gear of smaller diameter, and an annular planet pinion in mesh with both ring gears. The planet pinion is set in motion by a multiplicity of angularly spaced thrust-transmitting bodies, such as balls or pins, which are independently guided in apertures of an annular extension of the stationary member and bear upon an eccentric rigid with a drive shaft. The solid guide portions of this stationary extension can be used to accommodate energy-supply lines.