Biomedical finger assembly with ratcheting lock

Abstract

This disclosure provides systems, apparatuses, and devices for a prosthetic digit usable with persons with amputations at or proximal to the metacarpophalangeal joint. The device restores prehension in a person with missing fingers or thumb by providing opposition to forces in the extension direction via a spring-loaded pawl and locking rack ratchet mechanism, thereby allowing an individual to manipulate or stabilize objects. The digit may be spring-loaded in the extension direction by a torsion spring or other biasing member. The pawl may be automatically disengaged from the rack when the digit reaches full flexion, and the full flexion disengage stop may be adjustable. The pawl may be automatically engaged with the rack when the digit reaches full extension, and the extension stop may be adjustable. The pawl may contain a lateral feature that creates interference with the anchoring linkage under load and limits deflection of the structure.

Dependencies are inferred from the claim text.