US-12616626-B2 - Motion assist device

US12616626B2US 12616626 B2US12616626 B2US 12616626B2US-12616626-B2

Abstract

This motion assist device 100 assists with flexing and extending of fingers F 1 , F 2 of a user, the motion assist device 100 comprising: at least one arm 10 ; at least one connection member 20 configured so as to be capable of connecting the at least on arm 10 to each of the fingers F 1 , F 2 ; an arm support mechanism 30 that turnably supports the at least one arm 10 , the arm support mechanism 30 being configured so as to be mountable on the back Hb of the hand H of the user; an arm drive means 40 that causes the at least one arm 10 to turn; and a stopper 50 that extends from the arm support mechanism 30 , the stopper 50 being configured so as to restrict movement of the proximal phalanges of the fingers of the user by being in contact with the proximal phalanges. The at least one arm 10 is configured so as to turn while the distance Dr between the at least one connection member 20 and the turning center Cr of the at least one arm 10 is kept fixed.

Inventors

Kazunari Hatazaki
Masahiro KASUYA
Tatsuya Seki

Assignees

FRONTACT CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20210122
Priority Date: 20200206

Claims (19)

1 . A motion assistive device for assisting bending/stretching of fingers of a user, comprising: at least one arm; at least one connective member configured to be able to connect the at least one arm to the respective fingers, the at least one connective member being rotatably attached to the at least one arm; a base member that can be mounted on a back of a hand of the user; at least one attachment member for pivotably supporting the at least one arm on the base member; and a motor and/or at least one wire for causing the at least one arm to pivot; wherein the at least one arm is configured to pivot about a center of pivot while maintaining a constant distance between the at least one connective member and the center of pivot of the at least one arm; wherein the at least one arm has a shape that is bent in a direction of enveloping a hand side; wherein the base member and the at least one attachment member are configured so that the center of pivot of the at least one arm is disposed above an MP joint or towards a wrist side relative to the MP joint of the fingers; and wherein the at least one connective member is configured to connect the at least one arm between a DIP joint and a PIP joint, to a DIP joint, or to a portion distal to a DIP joint of the fingers.
2 . The motion assistive device of claim 1 , wherein the base member and the at least one attachment member are configured so that a position and/or orientation of the base member with respect to the back of the hand can be adjusted.
3 . The motion assistive device of claim 1 , wherein the at least one attachment member is configured so that a position where the at least one arm is fixed to the at least one attachment member can be adjusted in a longitudinal direction of the fingers.
4 . The motion assistive device of claim 1 , further comprising: at least one ball joint for adjusting a position and/or orientation of the center of pivot of the at least one arm.
5 . The motion assistive device of claim 1 , wherein the at least one connective member is configured to connect the at least one arm to the fingers such that a tip of the fingers is exposed.
6 . The motion assistive device of claim 1 , wherein the at least one connective member is made of a first material having a first rigidity and a second material having a second rigidity that is greater than the first rigidity.
7 . The motion assistive device of claim 1 , wherein the at least one arm is configured to have a structure without a joint between the center of pivot and the connective member.
8 . The motion assistive device of claim 1 , wherein the motion assistive device further comprises: a sensor for detecting a myoelectric signal that is generated when the user attempts to move a finger; and vibration generator that generates vibrations when the sensor has detected the myoelectric signal.
9 . The motion assistive device of claim 8 , wherein the motion assistive device comprises the at least one wire and the motor, wherein the at least one wire is connected to the respective at least one arm, and the motor is connected to the at least one wire, and wherein the motion assistive device further comprises: a first encoder for detecting a rotation angle of the at least one arm, and a second encoder for detecting a rotation angle of the motor, wherein the motion assistive device is configured to calculate tension of the at least one wire based on the rotation angle detected by the first encoder and the rotation angle detected by the second encoder.
10 . The motion assistive device of claim 9 , wherein the at least one wire and the motor are configured to drive the at least one arm so as not to interfere with a movement of the fingers of the user based on the calculated tension.
11 . The motion assistive device of claim 1 , wherein the motion assistive device comprises the at least one wire, and the at least one wire comprises: at least one first wire connected to the respective at least one arm; and at least one second wire connected to the respective at least one arm; and the fingers are bent by pulling the at least one first wire to pivot the at least one arm in one direction, and the fingers are stretched by pulling the at least one second wire to pivot the at least one arm in the opposite direction from the pivot in one direction.
12 . The motion assistive device of claim 1 , wherein the at least one arm is a plurality of arms, the at least one connective member is a plurality of connective members, and each of the plurality of arms is attached to corresponding one finger by each of the plurality of connective members.
13 . The motion assistive device of claim 1 , the base member and the at least one attachment member are configured so that a position of the center of pivot of the at least one arm can be adjusted in a direction of width of the hand.
14 . The motion assistive device of claim 1 further comprising a stopper configured to extend from a bottom of the at least one attachment member and restrict movement of a proximal phalanx of the fingers of the user by abutting the proximal phalanx.
15 . The motion assistive device of claim 1 , wherein the base member and the at least one attachment member are configured so that a position of attaching the at least one arm to the base member can be adjusted in a longitudinal direction of the fingers.
16 . The motion assistive device of claim 15 , wherein the base member is configured so that a position where the at least one attachment member is fixed to the base member can be adjusted in a longitudinal direction of the fingers.
17 . The motion assistive device of claim 4 , wherein the at least one arm comprises a plurality of arms, the plurality of arms comprising: a first arm connected to the base member via the at least one ball joint; and a second arm connected to the base member without the at least one ball joint interposed therebetween.
18 . The motion assistive device of claim 4 , wherein the at least one ball joint is configured to be selectively attachable to both a first side and a second side of the base member.
19 . The motion assistive device of claim 14 , wherein the base member has an anterior side, which is a side towards which the at least one arm extends, and a posterior side, which is the opposite side from the anterior side, wherein the base member has a flat surface that is substantially parallel to the back of the hand, and wherein the stopper is configured to be substantially parallel to the flat surface and extend towards the anterior side.

Description

This application is a national phase of International Application No. PCT/JP2021/002265 filed 22 Jan. 2021, which claims priority to Japan Application No. 2020-018898 filed 6 Feb. 2020, the entireties of which are hereby incorporated by reference. TECHNICAL FIELD The present invention relates to a motion assistive device. The present invention particularly relates to a device for assisting the bending/stretching of a finger of a hand. BACKGROUND ART A device that assists the bending/stretching of a finger of a hand that no longer moves as intended has been available. For example, Patent Literature 1 discloses a wearable motion assistive device having pivoting mechanisms corresponding to joints of each finger and an actuator for driving each pivoting mechanism as such a device for assisting finger joint movement. CITATION LIST Patent Literature [PTL 1] Japanese Laid-Open Publication No. 2002-345861 SUMMARY OF INVENTION Technical Problem However, the conventional wearable motion assistive device described above is provided with a pivoting mechanism for each joint of each finger of a human hand. Thus, the device has problems in terms of having a large number of parts and being heavy which imposes a significant burden on users. The objective of the present invention is to provide a motion assistive device, which has a mechanism for moving a finger that is simple and light weight with low burden on users. Solution to Problem The present invention provides, for example, the following items. Item 1 A motion assistive device for assisting bending/stretching of fingers of a user, comprising: at least one arm;at least one connective member configured to be able to connect the at least one arm to the respective fingers;an arm supporting mechanism for pivotably supporting the at least one arm, wherein the arm supporting mechanism is configured to be mountable on a back of a hand of the user;arm driving means for causing the at least one arm to pivot; anda stopper configured to extend from the arm supporting mechanism and restrict movement of a proximal phalanx of the fingers of the user by abutting the proximal phalanx;wherein the at least one arm is configured to pivot while maintaining a constant distance between the at least one connective member and a center of pivot of the at least one arm. Item 2 The motion assistive device of item 1, wherein the at least one connective member is configured to connect the at least one arm to a DIP joint or a middle phalanx of the fingers. Item 3 The motion assistive device of item 1 or 2, wherein the arm supporting mechanism comprises a base member that can be mounted on the back of the hand of the user, wherein the base member has an anterior side, which is a side towards which the at least one arm extends, and a posterior side, which is the opposite side from the anterior side, wherein the base member has a flat surface that is substantially parallel to the back of the hand, and wherein the stopper is configured to be substantially parallel to the flat surface and extend towards the anterior side. Item 4 The motion assistive device of any one of items 1 to 3, wherein the arm supporting mechanism is configured so that the center of pivot of the at least one arm is disposed on an MP joint or towards a wrist side relative to the MP joint of the fingers. Item 5 The motion assistive device of any one of items 1 to 4, wherein the arm supporting mechanism has: a base member that can be mounted on the back of the hand; andat least one attachment member, which supports the at least one arm pivotably about the center of pivot on the base member; and the attachment member is disposed on the base member. Item 6 The motion assistive device of item 5, wherein the arm supporting mechanism is configured so that a position and/or orientation of the base member with respect to the back of the hand can be adjusted. Item 7 The motion assistive device of item 5 or 6, wherein the arm supporting mechanism is configured so that a position of attaching the at least one arm to the base member can be adjusted in a longitudinal direction of the fingers. Item 8 The motion assistive device of item 7, wherein the at least one attachment member is configured so that a position where the at least one arm is fixed to the at least one attachment member can be adjusted in a longitudinal direction of the fingers. Item 9 The motion assistive device of item 7 or 8, wherein the base member is configured so that a position where the at least one attachment is fixed to the base member can be adjusted in a longitudinal direction of the fingers. Item 10 The motion assistive device of any one of items 5 to 9, wherein the arm supporting mechanism comprises: an adjustment mechanism for adjusting a position and/or orientation of the center of pivot of the at least one arm. Item 11 The motion assistive device of item 10, wherein the at least one arm comprises a plurality of arms, the plurality of arms comprisi