US 2024/0299192 A1 · PROSTHETIC THUMB WITH ROTATION AND COMPOUND FLEXION

Abstract

A prosthetic thumb having a rotation drive and articulation mechanism for causing rotation and flexion of metacarpal and phalange segments. A rotational mounting arrangement with angular contact bearing is preloaded axially. A flexion drive has a motor and gearbox adjacent and coplanar to each other, and mechanically coupled to a worm drive having a worm wheel on a second, parallel plane. A rigid linkage rotationally connects with the phalange and the worm wheel and causes flexion of the phalange segment. The thumb rotation drive rotates a metacarpal rotation wheel to cause rotation. A fixation plate supports the mechanism, such that a single structure takes all forces applied to the thumb digit, such as the plate and/or wrist, and not to a prosthetic hand structure. A potentiometer detects rotational position of the thumb digit. Some embodiments have a hollow worm gear with threaded shaft therethrough for high torque pressing states.

Claims24

Dependent claims

A prosthetic thumb comprising:

a fixation plate;
a thumb rotation drive supported by the fixation plate;
and
a thumb articulation mechanism supported by the fixation plate, the thumb articulation mechanism comprising:
a metacarpal rotation wheel configured to be rotated about a rotation axis by the thumb rotation drive to cause rotation of a metacarpal segment about the rotation axis;
a flexion drive inside a housing supported by the metacarpal segment and in mechanical communication with the metacarpal rotation wheel, the flexion drive configured to cause rotation of the metacarpal segment about a flexion axis;
and
an angular contact bearing assembly rotationally supporting the metacarpal rotation wheel about the rotation axis, the angular contact bearing assembly comprising:
a bolt supported by the fixation plate;
an angular contact bearing disposed about the bolt;
and
a nut attached to and preloading the angular contact bearing assembly.

9 more elements

A prosthetic thumb comprising:

a thumb rotation drive comprising a rotation motor, the thumb rotation drive configured to cause rotation of a metacarpal segment of the prosthetic thumb about a rotation axis;
and
a thumb articulation mechanism in mechanical communication with the thumb rotation drive and comprising a flexion motor, the thumb articulation mechanism configured to cause rotation of the metacarpal segment about a first flexion axis that is perpendicular to the rotation axis, the thumb articulation mechanism comprising:
a metacarpal rotation wheel configured to be rotated by the thumb rotation drive about the rotation axis, the metacarpal rotation wheel rotationally supporting the metacarpal segment about the first flexion axis;
a phalange segment having a proximal end rotatably coupled with a distal end of the metacarpal segment at a second flexion axis;
and
a rigid linkage having a proximal end rotatably coupled to the metacarpal rotation wheel at a first fulcrum offset from the first flexion axis, and a distal end of the rigid linkage rotatably coupled to the proximal end of the phalange segment at a second fulcrum that is offset from the second flexion axis,
wherein rotation of the metacarpal segment about the first flexion axis causes rotation of the phalange segment about the second flexion axis.

5 more elements

Dependencies are inferred from the claim text.

Prosthetic thumb with rotation and compound flexion

Life of this patent

Prosthetic thumb with rotation and compound flexion

Life of this patent

Abstract

Claims24