Abstract: A joint having two-axis construction having a distal member and a main member joined in co-linear pivotal relation that provides enhanced joint strength and compactness. Hydraulics further provide variable extension assist and an infinite number of flexion stops for controlled flexion flow, and two gears provide a functional gear ratio that also promotes compact construction by reducing the amount of hydraulic piston travel required for maximum joint extension. A drive gear associated with the main member is positioned between the distal end of the piston and a transfer gear partially press-fit into a cut-out in the distal member, to provide needed radial hydraulic force transfer. Although it is contemplated for joint use to be primarily in orthotic devices that assist the movement of an inadequately functioning body limb, any application for which the mechanical joint's compact configuration would provide assistance or technical advantage is considered to be within its scope.

Abstract: A compact and efficient stop for establishing the position of maximum extension in a mechanical joint, which comprises a free-floating piston, a piston-retaining pin, and a resilient bumper positioned to engage one end of the piston. The piston, retaining pin, and bumper are located on one side of the joint. A cross stop bushing on the opposing side of the mechanical joint is positioned to engage the exposed end of the piston when the joint is in its position of maximum extension. Applications may include, but are not limited to, use in orthotic and prosthetic devices wherein a larger tolerance in the range of motion is provided for a locking mechanism to engage as the joint reaches maximum extension, while any unwanted feeling of free movement in the joint at full extension is concurrently dampened. A secondary advantage is a softer extension stop for a user.

Abstract: A compact and efficient stop for establishing the position of maximum extension in a mechanical joint, which comprises a free-floating piston, a piston-retaining pin, and a resilient bumper positioned to engage one end of the piston. The piston, retaining pin, and bumper are located on one side of the joint. A cross stop bushing on the opposing side of the mechanical joint is positioned to engage the exposed end of the piston when the joint is in its position of maximum extension. Applications may include, but are not limited to, use in orthotic and prosthetic devices wherein a larger tolerance in the range of motion is provided for a locking mechanism to engage as the joint reaches maximum extension, while any unwanted feeling of free movement in the joint at full extension is concurrently dampened. A secondary advantage is a softer extension stop for a user.

Abstract: A joint using a combination of hydraulics and ball bearings to convert liner motion into a radial motion and thereby provide both variable extension assist, as well as an infinite number of flexion stops for controlled flexion flow. Applications may include, but are not limited to, orthotic devices which facilitate the extension and flexion of human joint, such as a knee. The compact configuration of the present invention would provide the cosmetic advantage of allowing such orthotic devices to fit more easily under clothing wherein they would be less noticeable during use.