STRENGTH ASSIST DEVICE

A strength assist device includes: a base frame; a plurality of rotating bodies provided on left and right sides of the base frame, and rotatably connected to the base frame; a plurality of actuators rotatably connected to the respective rotating bodies, and forming respective restoring torques according to rotation angles with respect to the rotating bodies; and a cable connecting the rotating bodies. In particular, rotational motions of the rotating bodies with respect to the base frame are restricted against each other by a tension of the cable.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2020-0156932, filed on Nov. 20, 2020, the entire contents of which are incorporated herein by reference.

FIELD

The present disclosure relates to a strength assist device, and more particularly, to a strength assist device designed to assist users' (pedestrians' or operators') activities or tasks.

BACKGROUND

A strength assist device designed to support a user's activities or tasks may reduce a load applied to part of the user's body such as the waist during the activities or tasks by generating a torque by elasticity in the vicinity of a rotatable joint such as the hip joint.

Such a strength assist device is usually provided with structures generating torque, which are formed on both left and right sides thereof, respectively. The strength assist device may be divided into: i) a device in which the two structures are connected to each other so that the two structures may move in an interlocking manner; and ii) a device in which the two structures are provided  independently of each other so that the two structures may move independently.

However, we have discovered that the size of the strength assist device cannot be adjusted according to the user's body size and shape, and that the two structures generating torque in the strength assist device operate independently such that the user feels uncomfortable when the user wearing the strength assist device is walking.

SUMMARY

An aspect of the present disclosure provides a strength assist device capable of adjusting its size by taking a user's body type into consideration, and significantly reducing an uncomfortable feeling that may occur in a walking process or the like.

According to an aspect of the present disclosure, a strength assist device may include: a base frame; a first rotating body provided on a left side of the base frame, and rotatably connected to the base frame; a second rotating body provided on a right side of the base frame, and rotatably connected to the base frame; a first actuator rotatably connected to one side of the first rotating body, and forming a first restoring torque according to a rotation angle with respect to the first rotating body; a second actuator rotatably connected to one side of the second rotating body, and forming a second restoring torque according to a rotation angle with respect to the second rotating body; and a cable connecting the first rotating body to the second rotating body, wherein a rotational motion of the first rotating body with respect to the base frame and a rotational  motion of the second rotating body with respect to the base frame may be restricted against each other by a tension of the cable.

The base frame may include: a first frame to which the first rotating body is rotatably connected; and a second frame to which the second rotating body is rotatably connected. The first frame and the second frame may be movable relative to each other.

The cable may surround at least a portion of an outer circumference of the first rotating body and at least a portion of an outer circumference of the second rotating body.

When the first actuator and the second actuator rotate with respect to the base frame in the same direction, the first actuator may rotate with respect to the first rotating body so that the first restoring torque may be formed, and the second actuator may rotate with respect to the second rotating body so that the second restoring torque may be formed.

When the first actuator and the second actuator rotate with respect to the base frame in opposite directions, the first actuator may be fixed to the first rotating body so that the first restoring torque may not be formed, and the second actuator may be fixed to the second rotating body so that the second restoring torque may not be formed.

The actuator may include: an actuator body part forming a body of the actuator; and a plate rotatably connected to the actuator body part, and fixedly connected to the rotating body.

The rotating body may include: a rotating body part forming a body of the rotating body; and a locking portion protruding from the rotating body part.

The plate may include a recessed portion which is recessed inwardly from an outer peripheral edge of the plate, and the locking portion may be engaged with the recessed portion.

The rotating body may further include a latch portion engaged with the locking portion, and the latch portion may move the locking portion to allow the locking portion to be engaged with the recessed portion or be disengaged from the recessed portion.

When the locking portion is engaged with the recessed portion, the plate may be fixedly connected to the rotating body.

The restoring torque may be formed when the actuator body part rotates with respect to the rotating body and the plate in a state in which the plate is fixedly connected to the rotating body.

The actuator may further include a linkage structure provided inside the actuator body part and including a plurality of links and a plurality of elastic bodies, and the restoring torque may be formed by a position change between the links and the elastic bodies which is made when the actuator body part rotates with respect to the plate.

When the locking portion is disengaged from the recessed portion, the plate may be rotatable with respect to the rotating body and be fixed to the actuator body part.

The base frame may further include a third frame between the first frame and the second frame, each of the first frame and the second frame may include a horizontal guide hole which is a through hole formed in the first frame and the second frame and extending in a horizontal direction, the third frame may include a fixing portion inserted into the horizontal guide hole, and the fixing portion may  move along the horizontal guide hole in the horizontal direction so that a gap between the first frame and the second frame may be adjusted.

The cable may be a bowden cable.

The first frame may include a first pulley, the second frame may include a second pulley, the third frame may include a third pulley, and the third pulley may move vertically with respect to the first pulley and the second pulley.

The third frame may further include a vertical guide hole which is a through hole formed in the third frame and extending in a vertical direction, and the third pulley may be inserted into the vertical guide hole.

The cable may be provided between the first pulley and the third pulley, and the cable may be provided between the second pulley and the third pulley.

DETAILED DESCRIPTION

Hereinafter, the structure and operation principle of a strength assist device according to exemplary forms of the present disclosure will be described in detail with reference to the accompanying drawings.

FIG. 1illustrates a perspective view of a strength assist device according to an exemplary form of the present disclosure, which is worn by a user, andFIG. 2illustrates an enlarged perspective view of the strength assist device illustrated inFIG. 1. In addition,FIG. 3illustrates an enlarged perspective view of an actuator and a rotating body in a strength assist device according to an exemplary form of the present disclosure.

As illustrated inFIG. 1, a strength assist device10may include a base frame300. The base frame300may form a body of the  strength assist device10, and may surround a part of a user's body so that the strength assist device10may be worn by the user. As illustrated inFIGS. 1 and 2, the base frame300may surround the user's waist. In addition, the strength assist device10may reduce a load applied to the user's waist.

The base frame300may be an assembly of a plurality or components. For example, as illustrated inFIGS. 1 and 2, the base frame300may include a first frame310provided on the left side and a second frame320provided on the right side. Here, the first frame310and the second frame320may be able to move relative to each other. In one form, when the user wears the strength assist device10, the first frame310and the second frame320may move relative to each other in a horizontal direction. Thus, by moving the first frame310and the second frame320according to the user's body type, a transverse length of the strength assist device10may be adjusted.

Meanwhile, the strength assist device10according to an exemplary form of the present disclosure may further include a rotating body200provided on a side of the base frame300and rotatably connected to the base frame300. More specifically, the rotating body200may include a first rotating body210provided on the left side of the base frame300and rotatably connected to the base frame300, and a second rotating body220provided on the right side of the base frame300and rotatably connected to the base frame300. In one form, the first rotating body210may be connected to the left side of the first frame310and rotatably connected to the first frame310, and the second rotating body220may be connected to the right side of the second frame320and rotatably connected to the  second frame320.

In addition, the strength assist device10according to an exemplary form of the present disclosure may further include an actuator100rotatably connected to one side of the rotating body200. The actuator100may form a restoring torque according to a rotation angle of the actuator100with respect to the rotating body200. Thus, the restoring torque formed by the actuator100may help reduce a load applied to the user.

FIG. 4illustrates various side views of the rotation of an actuator with respect to a rotating body in a strength assist device according to an exemplary form of the present disclosure.

Referring toFIG. 4, the rightmost reference view illustrates a state in which a restoring torque is not formed as the actuator100does not rotate with respect to the rotating body200, and the other views illustrate a state in which a restoring torque is formed as the actuator100rotates with respect to the rotating body200. In particular, a rotation angle at which the actuator100rotates with respect to the rotating body200is illustrated as gradually increasing in the views provided to the left of the reference view inFIG. 4. As the rotation angle increases, the restoring torque may increase. InFIG. 4, when the actuator100rotates with respect to the rotating body200in a clockwise direction, the restoring torque generated by the actuator100may be formed in a counterclockwise direction.

Referring toFIGS. 1 and 2, the actuator100may include a first actuator110rotatably connected to one side of the first rotating body210and forming a first restoring torque according to a  rotation angle with respect to the first rotating body210, and a second actuator120rotatably connected to one side of the second rotating body220and forming a second restoring torque according to a rotation angle with respect to the second rotating body220.FIGS. 1 and 2illustrate the first actuator110provided on the left side of the first rotating body210and the second actuator120provided on the right side of the second rotating body220.

Referring toFIGS. 1 and 2, the strength assist device10according to an exemplary form of the present disclosure may further include a cable400connecting the first rotating body210to the second rotating body220. As illustrated inFIG. 2, the cable400may surround at least a portion of an outer circumference of the first rotating body210and at least a portion of an outer circumference of the second rotating body220.

The cable400may restrict a rotational motion of the first rotating body210with respect, to the base frame300and a rotational motion of the second rotating body220with respect to the base frame300. More specifically, the rotational motion of the first rotating body210with respect to the base frame300and the rotational motion of the second rotating body220with respect to the base frame300may be restricted against each other by a tension of the cable400. According to an exemplary form of the present disclosure, when the first rotating body210rotates with respect to the base frame300in one direction, the second rotating body220may rotate with respect to the base frame300in the opposite direction due to the tension of the cable400. For example, as indicated by arrows illustrated inFIG 2, when the first rotating body210rotates with respect to the base  frame300in a clockwise direction, the cable400may move in a direction of winding the first rotating body210. In this case, due to the tension of the cable400, the cable400may move in a direction of being unwound from the second rotating body220, and accordingly the second rotating body220may rotate in a counterclockwise direction. Thus, the rotation directions of the first rotating body210and the second rotating body220may be opposite to each other by the tension of the cable400.

More specifically, according to an exemplary form of the present disclosure, when the rotation direction of the first actuator110and the rotation direction of the second actuator120with respect to the base frame300are opposite to each other by the tension of the cable400, the first actuator110may be fixed to the first rotating body210so that the aforementioned first restoring torque may not be formed, and the second actuator120may be fixed to the second rotating body220so that the aforementioned second restoring torque may not be formed.

In one form, when the first actuator110and the second actuator120rotate with respect to the base frame300in the opposite directions, the first rotating body210may rotate together with the first actuator110with respect to the base frame300, and the second rotating body220may rotate together with the second actuator120with respect to the base frame300. In this case, as first actuator110does not rotate with respect to the first rotating body210, the first restoring torque may not be formed, and as the second actuator120does not rotate with respect to the second rotating body220, the second restoring torque may not be formed.

This may be applied to a case in which the user wearing the strength assist device10is walking. For example, the following case may be considered: the user wears the strength assist device10in a manner that allows the base frame300to surround the user's waist, mounts the first actuator110on the user's left leg with the first rotating body210located on the user's left hip joint, and mounts the second actuator120on the user's right leg with the second rotating body220located on the user's right hip joint. For example, in the walking process of the user, when the user's left leg is positioned forward, the user's right leg may be positioned backward, and accordingly, the first actuator110may rotate forward, and the second actuator120may rotate backward.

However, when the user is simply walking, the user does not need to be assisted by the restoring torque generated by the strength assist device10, so the first restoring torque and the second restoring torque of the first actuator110and the second actuator120are not required. According to an exemplary form of the present disclosure, in the user's walking process, the strength assist device10may allow the first rotating body210and the second rotating body220to rotate in the opposite directions by the tension of the cable400, thereby allowing the first rotating body210and the second rotating body220to be fixed to the first actuator110and the second actuator120, respectively. Thus, the aforementioned restoring torque may not be generated when the user is simply walking.

On the other hand, according to an exemplary form of the present disclosure, when the rotation direction of the first actuator110and the rotation direction of the second actuator120with  respect to the base frame300are the same as each other, the first actuator110may rotate with respect to the first rotating body210so that the first restoring torque may be formed, and the second actuator120may rotate with respect to the second rotating body220so that the second restoring torque may be formed.

In another form, when the first actuator110and the second actuator120rotate with respect to the base frame300in the same direction, the first actuator110may rotate with respect to the first rotating body210while the first rotating body210is fixed to the base frame300, and the second actuator120may rotate with respect to the second rotating body220while the second rotating body220is fixed to the base frame300.

This may be applied to a case in which the user wearing the strength assist device10is performing a task. For example, when the user wearing the strength assist device10bends the waist to lift an object, the user's waist may rotate with respect to the user's legs. Accordingly, a relative rotational motion may occur between the actuators110and120mounted on the user's legs and the base frame300.

Here, the rotating bodies210and220connected to the actuators110and120try to rotate in a direction in which the actuators110and120rotate with respect to the base frame300. However, since the first rotating body210and the second rotating body220try to rotate in the same direction, the tension of the cable400may increase, and accordingly, the first rotating body210and the second rotating body220may fail to rotate with respect to the base frame300, but may be fixed to the base frame300. Thus, a  rotation angle may be formed between the first rotating body210and the first actuator110and between the second rotating body220and the second actuator120. As a result, the first restoring torque and the second restoring torque may be formed by the first actuator110and the second actuator120, respectively, and a load applied to the user's waist may be significantly reduced due to the first and second restoring torques.

Meanwhile, referring toFIG. 3, the actuator100may include an actuator body part102forming a body of the actuator100, and a plate104rotatably connected to the actuator body part102and fixedly connected to the rotating body200.

In addition, the rotating body200may include a rotating body part202forming a body of the rotating body200, and a locking portion204protruding from the rotating body part202in one direction.

As described above, the plate104may be fixedly connected to the rotating body200. However, according to an exemplary form of the present disclosure, the plate104and the rotating body200may also be released (disengaged) from each other according to the user's intention.

More specifically, as illustrated inFIG. 3, the plate104may include a recessed portion106which is recessed inwardly from an outer peripheral edge of the plate104. The locking portion204may be engaged with the recessed portion106. When the locking portion204is engaged with the recessed portion106, the plate104may be fixedly connected to the rotating body200, and when the locking portion204is disengaged from the recessed portion106, the plate104and the rotating body200may be released from each other. Meanwhile,FIGS. 5 and 6illustrate the plate104having two recessed portions106. In this case, the locking portion204may be selectively engaged with any one of the two recessed portions106.

FIG. 5illustrates the engagement of a plate of an actuator and a rotating body in a strength assist device according to an exemplary form of the present disclosure, andFIG. 6illustrates the disengagement of a plate of an actuator and a rotating body in a strength assist device according to an exemplary form of the present disclosure.

Referring toFIGS. 5 and 6, the rotating body200may further include a latch portion206engaged with the locking portion204and being movable. According to an exemplary form of the present disclosure, the latch portion206may move the locking portion204to allow the locking portion204to be engaged with the recessed portion106or be disengaged from the recessed portion106. In particular, as illustrated inFIG. 5, when the locking portion204is engaged with the recessed portion106, the plate104may be fixedly connected to the rotating body200as described above.

In particular, the aforementioned restoring torque may be formed when the actuator body part102rotates with respect to the rotating body200and the plate104in a state in which the plate104is fixedly connected to the rotating body200. More specifically, the actuator100may further include a linkage structure (not shown) provided inside the actuator body part102and including a plurality of links and a plurality of elastic bodies. Here, the aforementioned restoring torque may be formed by a position change between the links  and the elastic bodies which is made when the actuator body part102rotates with respect to the plate104.

Meanwhile, as illustrated inFIG. 6, when the latch portion206moves the locking portion204and the locking portion204is disengaged from the recessed portion106, the plate104may freely rotate with respect to the rotating body200and may be fixed to the actuator body part102. The following case may be exemplified: when the locking portion204is disengaged from the recessed portion106, the user wearing the strength assist device10is sitting on a chair to relax. In this case, since the restoring torque is not required, the locking portion204may be disengaged from the recessed portion106so that a rotational motion between the plate104and the actuator body part102may not occur.

FIG. 7illustrates a strength assist device according to an exemplary form of the present disclosure, which is worn by a user in a state in which a transverse length of the strength assist device is increased, andFIG. 8illustrates a strength assist device according to an exemplary form of the present disclosure, which is worn by a user in a state in which a transverse length of the strength assist device is reduced.

Referring toFIGS. 7 and 8, the base frame300may further include a third frame330between the first frame310and the second frame320.

Here, each of the first frame310and the second frame320may include a horizontal guide hole340which is a through hole formed in the first frame310and the second frame320and extending in a horizontal direction, and the third frame330may include a  fixing portion350inserted into the horizontal guide hole340.

The fixing portion350may move along the horizontal guide hole340in the horizontal direction, so that a gap between the first frame310and the second frame320may be adjusted. According to an exemplary form of the present disclosure, by adjusting a horizontal position of the fixing portion350in the horizontal guide hole340, the transverse length of the strength assist device10may be adjusted. For example, when a user with a large body type wears the strength assist device10, the fixing portion350may be positioned in or be adjacent to an inner end portion of the horizontal guide hole340so that the transverse length of the strength assist device10may be increased as illustrated inFIG. 7. When a user with a small body type wears the strength assist device10, the fixing portion350may be positioned in or be adjacent to an outer end portion of the horizontal guide hole340so that the transverse length of the strength assist device10may be reduced as illustrated inFIG. 8.

Meanwhile, according to an exemplary form of the present disclosure, the cable400may be a bowden cable. The bowden cable may be a flexible type cable used to transmit force or energy, and may include a cable housing and an inner cable provided inside the cable housing. The bowden cable may transmit the force or energy by the relative motion of the inner cable with respect to the cable housing. Details of the bowden cable can be understood based on the prior art, and various types of bowden cable structures known in the prior art may be applied to the cable400.

FIG. 9illustrates a strength assist device according to  another exemplary form of the present disclosure, which is worn by a user in a state in which a transverse length of the strength assist device is increased, andFIG. 10illustrates a strength assist device according to another exemplary form of the present disclosure, which is worn by a user in a state in which a transverse length of the strength assist device is reduced. Hereinafter, a strength assist device10according to another exemplary form of the present disclosure will be described by focusing on differences in comparison with the strength assist device10according to the previous exemplary form. Unless otherwise defined, the above-described features of the strength assist device in the previous exemplary form may be equally applied to the following exemplary form of the present disclosure.

According to another exemplary form of the present disclosure, the first frame310may include a first pulley360, the second frame320may include a second pulley370, and the third frame330may include a third pulley332. The third pulley332may move vertically with respect to the first pulley360and the second pulley370.

More specifically, the third frame330may further include a vertical guide hole334which is a through hole formed in the third frame330and extending in a vertical direction. Here, the third pulley332may be inserted into the vertical guide hole334. Thus, the third pulley332may move vertically along the vertical guide hole334.

Meanwhile, as illustrated inFIGS. 9 and 10, the cable400may be provided between the first pulley360and the third pulley332, and be provided between the second pulley370and the third pulley332.

According to another exemplary form of the present disclosure, when a user with a small body type wears the strength assist device10, it may be desired to reduce the transverse length of the strength assist device10as illustrated inFIG. 10. In this case, however, the tension of the cable400may be reduced, and accordingly, the restriction between the first rotating body210and the second rotating body220by the cable400may not be achieved properly.

According to another exemplary form of the present disclosure, the third pulley332may move upwardly so that the tension of the cable400may be maintained even if the transverse length of the strength assist device10is reduced. In this case, a portion of the cable400between the first pulley360and the third pulley332and a portion of the cable400between the second pulley370and the third pulley332may move upwardly by the third pulley332. When a user with a large body type wears the strength assist device10, the third pulley332may move downwardly as illustrated inFIG. 9so that the tension of the cable400may be maintained.

As set forth above, the strength assist device according to exemplary forms of the present disclosure may adjust its size by taking the user's body type into consideration, and significantly reduce an uncomfortable feeling that may occur in the walking process or the like.

Hereinabove, although the present disclosure has been described with reference to exemplary forms and the accompanying drawings, the present disclosure is not limited thereto, but may be variously modified and altered by those skilled in the art to which  the present disclosure pertains without departing from the spirit and scope of the present disclosure.