Underactuated prosthetic hand

Patent metadata

Field	Value
Publication number	US-11278432-B2
Application number	US-201917053503-A
Country	US
Kind code	B2
Filing date	May 6, 2019
Priority date	May 9, 2018
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

Underactuated prosthetic hand including base body; first and second prosthetic fingers each hinged to the base body; first control cable; actuator to move the first control cable; and for each pair of fingers second control cable having control ends associated with the first and second fingers; and transmission block to allow first control cable to control second control cable; transmission block includes guide integral with base body and defining sliding axis; movable element sliding along guide; first pulley for sliding first control cable hinged to movable element and second pulley for sliding second control cable hinged to the movable element so actuator, when moving first cable, determines moveable element translational movement to displace second control cable and the fingers; and elastic means opposing moveable element translational movement so the moveable element translational movement opposes elastic means allowing them to facilitate return to moveable element initial position.

First claim

The invention claimed is:

1. An underactuated prosthetic hand comprising
a base body;
at least a pair of prosthetic fingers comprising a first prosthetic finger and a second prosthetic finger; each of said prosthetic fingers being hinged to said base body;
a first control cable;
an actuator adapted to move said first control cable;
and for each one of said pair of prosthetic fingers
a second control cable having a first control end associated with said first prosthetic finger and a second control end associated with said second prosthetic finger; and
a transmission block adapted to allow said first control cable to control said second control cable;

wherein said transmission block comprises
a guide integral with said base body and defining a sliding axis;
a movable element sliding along said guide; and
a first pulley for the sliding of said first control cable hinged to said movable element and
a second pulley for the sliding of said second control cable hinged to said movable element so that said actuator, when it moves said first control cable, brings about a translational movement of said movable element along said guide, causing a displacement of said second control cable and therefore of said prosthetic fingers; and
elastic means suitable to work in opposition to a translational movement of said movable element so that said translational movement of said movable element is performed in opposition to said elastic means, allowing said elastic means to command the return to the initial position of said movable element when said actuator is deactivated, so as to facilitate the return to the initial position of said main fingers; and
wherein said underactuated prosthetic hand comprises two of said at least one pair of prosthetic fingers; one said first control cable, two of said second control cable and two transmission blocks, each of which adapted to allow said first control cable to simultaneously control both said second control cables and thus both said pairs of prosthetic fingers.

2. The underactuated prosthetic hand according to claim 1 , wherein said two transmission blocks comprise guides substantially parallel to each other.

3. The underactuated prosthetic hand according to claim 1 , wherein each transmission block comprises two of said guide substantially parallel to each other; and wherein said movable element slides along said two guides.

4. The underactuated prosthetic hand according to claim 1 , wherein each of said prosthetic fingers comprises a return block adapted to work in opposition to a rotation of said prosthetic finger controlled by said second control cable.

5. The underactuated prosthetic hand according to claim 1 , comprising an additional finger adapted to work in opposition to said prosthetic fingers; and wherein said first control cable is adapted to control said additional finger.

6. The underactuated prosthetic hand according to claim 5 , wherein said additional finger comprises one said return block adapted to work in opposition to a rotation of said additional finger controlled by said first control cable.

7. The underactuated prosthetic hand according to claim 1 , wherein said pulleys define rotation axes substantially parallel to each other and substantially perpendicular to said sliding axis.

8. The underactuated prosthetic hand according to claim 1 , which is mono-actuated and comprises a single actuator.

9. The underactuated prosthetic hand according to claim 1 , wherein said elastic means comprise at least one compression coil spring extending coaxially with said sliding axis.

10. The underactuated prosthetic hand according to claim 9 , wherein each transmission block comprises two of said guide substantially parallel to each other; and wherein said movable element slides along said two guides.

11. The underactuated prosthetic hand according to claim 10 , wherein each of said prosthetic fingers comprises a return block adapted to work in opposition to a rotation of said prosthetic finger controlled by said second control cable.

Assignees

• Fondazione St Italiano Tecnologia
• Inail Istituto Naz Per Lassicurazione Contro Gli Infortuni

Inventors

• Traverso Simone
• Lince Andrea
• Laffranchi Matteo
• De Michieli Lorenzo
• Boccardo Nicolò

Classifications

• A61F2002/5072

  having spring elements · CPC title

• A61F2002/5038

  Hinged joint, e.g. with transverse axle restricting the movement · CPC title

• A61F2/583 Primary

  Hands; Wrist joints · CPC title

• A61F2/586 Primary

  Fingers · CPC title

• A61F2002/587

  Thumbs · CPC title