Patent Publication Number: US-2023150115-A1

Title: Apparatus for assisting muscular strength

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims under 35 U.S.C. § 119(a) the benefit of Korean Patent Application No. 10-2021-0156942 filed on Nov. 15, 2021, the entire contents of which are incorporated herein by reference. 
     BACKGROUND 
     (a) Field 
     The present disclosure relates to an apparatus for assisting muscular strength, and more particularly, an apparatus for assisting muscular strength of a user&#39;s waist muscles. 
     (b) Description of Related Art 
     An apparatus for assisting strength of waist muscles, which is capable of assisting strength of a user&#39;s waist muscles while the user works, generates torque by applying elasticity to body portions in the vicinity of rotatable joints such as hip joints, thereby reducing a load applied to the user&#39;s waist during the work process. 
     In general, such an apparatus for assisting strength of waist muscles often has structures disposed at two left and right sides of the apparatus and configured to generate torque. In this case, the apparatus for assisting muscular strength may broadly have Feature i) in which the two structures are connected to each other and the motions of the two structures are performed in conjunction with each other, or Feature ii) in which the two structures are provided independently of each other and the motions of the two structures are performed independently of each. In the case in which the apparatus for assisting strength of waist muscles has Feature i), the apparatus is sometimes designed such that the apparatus generates torque for assisting muscular strength when the two structures rotate in the same direction (e.g., the user bends his/her waist), whereas the apparatus does not generate torque for assisting muscular strength when the two structures rotate in the opposite directions (e.g., the user walks). 
     Meanwhile, in the related art, the apparatus for assisting strength of waist muscles includes main components positioned to apply torque to the user&#39;s back. However, in this case, because the main components often have structures protruding rearward, the user often cannot easily sit in a chair having a backrest while the user wears the apparatus for assisting strength of waist muscles. 
     SUMMARY 
     In exemplary embodiments, the present disclosure provides for an apparatus for assisting the strength of waist muscles, wherein the structure of the apparatus is configured to enable a user to sit in a chair having a backrest while the user wears the apparatus. 
     An exemplary embodiment of the present disclosure provides an apparatus for assisting muscular strength, the apparatus including: an upper frame configured to be fixed to a user&#39;s upper body; a lower frame disposed below the upper frame and configured to be fixed to the user&#39;s lower body and rotatable relative to the upper frame; a wire disposed across the upper frame and the lower frame; and a force generating unit coupled to one side of the upper frame, whereby when the lower frame rotates in a first direction D 1  relative to the upper frame, the force generating unit applies a force to the lower frame in a second direction D 2  opposite to the first direction D 1 , in which the force generating unit includes: a first movable member configured to be movable in an upward/downward direction H; a second movable member disposed below the first movable member and configured to be movable in the upward/downward direction H; and a main spring part having one side fixed to the first movable member and the other side fixed to the second movable member. 
     The force generating unit may further include first pulley members fixed to one side of the second movable member, and the wire may extend upward from the lower frame, surround upper portions of the first pulley members, and then extend downward toward the lower frame. 
     The lower frame may include second pulley members coupled to be rotatable relative to the upper frame, and ends of the wire may be fixed to the second pulley members. 
     The lower frame may further include: a right lower frame configured to be fixed to the user&#39;s right leg; and a left lower frame configured to be fixed to the user&#39;s left leg, the second pulley members may be respectively disposed on the right and left lower frames, and one end of the wire may be fixed to the second pulley member disposed on the right lower frame, and the other end of the wire, which is opposite to one end of the wire, may be fixed to the second pulley member disposed on the left lower frame. 
     The upper frame may include: an up/down extension region extending in the upward/downward direction H and coupled to the force generating unit; a right extension region extending in a right direction from a lower portion of the up/down extension region and connected to the right lower frame by means of the second pulley member; and a left extension region extending in a left direction from the lower portion of the up/down extension region and connected to the left lower frame by means of the second pulley member. 
     The main spring part may include a first main spring part having one end coupled to an upper end region of the first movable member and the other end coupled to an upper end region of the second movable member. 
     The main spring part may further include a second main spring part having one end coupled to a lower end region of the first movable member and the other end coupled to a lower end region of the second movable member. 
     The lower end region of the first movable member may be disposed between the upper end region of the second movable member and the lower end region of the second movable member. 
     The first main spring part or the second main spring part may include a plurality of spring members. 
     An elastic modulus of the first main spring part may correspond to an elastic modulus of the second main spring part. 
     The up/down extension region may further include a latch member having a lower region configured to be rotatable about an upper region of the latch member, and the lower region of the latch member may be coupled to or separated from the first movable member according to a rotation of the latch member. 
     The first movable member may include a recessed portion recessed in a forward/rearward direction, and the latch member may include a protrusion configured to be inserted into the recessed portion or separated from the recessed portion according to the rotation of the latch member. 
     The force generating unit may further include an auxiliary spring part having one end coupled to the up/down extension region and the other end coupled to the first movable member. 
     An elastic modulus of the auxiliary spring part may be smaller than an elastic modulus of the first main spring part. 
     One end of the auxiliary spring part may be coupled to an upper end of the latch member, and the other end of the auxiliary spring part may be coupled to an upper end of the first movable member. 
     The wire may surround a lower region of the second pulley member disposed on the right lower frame and surround a lower region of the second pulley member disposed on the left lower frame. 
     The apparatus may further include: a harness coupled to one side of the upper frame, in which the harness includes: a first surrounding member configured to surround the user&#39;s chest; a plurality of second surrounding members configured to surround the user&#39;s shoulders; and a handle member having one side configured to extend forward across the user&#39;s the shoulders and the other side connected to the upper region of the latch member, and when one side of the handle member is pulled forward, the upper region of the latch member may be rotated, such that the lower region of the latch member is rotated rearward. 
     The upper frame may further include third pulley members respectively fixed to the right and left extension regions, and the wire may surround lower regions of the third pulley members and then extend upward toward the first pulley members. 
     The first and second movable members may each have a shape having a penetrated central region. 
     Embodiments of the present disclosure are directed to an apparatus for assisting strength of waist muscles that has a structure configured to enable a user to sit in a chair having a backrest while the user wears the apparatus. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated herein and constitute part of this specification, are illustrative of particular embodiments of the present disclosure and do not limit the scope of the present disclosure. 
         FIG.  1    is a rear view illustrating a state in which a user wears an apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  2    is a side view illustrating a state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  3    is a view illustrating a structure for coupling an upper frame and a force generating unit of the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  4    is an enlarged view of a harness of the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  5    is a perspective view illustrating a state in which the upper frame is connected to the force generating unit by means of a latch member in the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  6    is a perspective view illustrating a state in which the upper frame and the force generating unit, which have been connected by means of the latch member, are disconnected from each other in the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  7    is a view illustrating the relative positional relationships between components of the force generating unit and the apparatus for assisting muscular strength before the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  8    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength immediately after the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  9    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength when the user bends his/her waist in the state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
         FIG.  10    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength in the state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure and in which the latch member and the force generating unit are disconnected from each other. 
         FIG.  11    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength when the user bends the waist in the state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure and in which the latch member and the force generating unit are disconnected from each other. 
     
    
    
     DETAILED DESCRIPTION 
     The above and other objects, features and advantages of embodiments of the present disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. These terms are merely intended to distinguish one component from another component, and the terms do not limit the nature, sequence or order of the constituent components. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Throughout the specification, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. In addition, the terms “unit”, “-er”, “-or”, and “module” described in the specification mean units for processing at least one function and operation, and can be implemented by hardware components or software components and combinations thereof. 
     Although exemplary embodiment is described as using a plurality of units to perform the exemplary process, it is understood that the exemplary processes may also be performed by one or plurality of modules. 
     Unless specifically stated or obvious from context, as used herein, the term “about” is understood as within a range of normal tolerance in the art, for example within 2 standard deviations of the mean. “About” can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear from the context, all numerical values provided herein are modified by the term “about”. 
     Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the exemplary drawings. In the drawings, the same reference numerals will be used throughout to designate the same or equivalent elements. In addition, a detailed description of well-known features or functions will be ruled out in order not to unnecessarily obscure the gist of the present disclosure. 
     according to an example embodiment of the present disclosure Apparatus for Assisting Muscular Strength 
       FIG.  1    is a rear view illustrating a state in which a user wears an apparatus for assisting muscular strength according to an example embodiment of the present disclosure, and  FIG.  2    is a side view illustrating a state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure.  FIG.  3    is a view illustrating a structure for coupling an upper frame and a force generating unit of the apparatus for assisting muscular strength according to an example embodiment of the present disclosure, and  FIG.  4    is an enlarged view of a harness of the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. In addition,  FIG.  5    is a perspective view illustrating a state in which the upper frame is connected to the force generating unit by means of a latch member in the apparatus for assisting muscular strength according to an example embodiment of the present disclosure, and  FIG.  6    is a perspective view illustrating a state in which the upper frame and the force generating unit, which have been connected by means of the latch member, are disconnected from each other in the apparatus for assisting muscular strength according to an example embodiment of the present disclosure. 
     The apparatus  10  for assisting muscular strength may be configured to generate a force for assisting strength of a user&#39;s waist muscles. For example, when the user bends his/her waist, the apparatus  10  for assisting muscular strength may be configured to reduce a load applied to the user&#39;s waist by generating the force in the direction in which the user&#39;s waist is stretched. In addition, the user may optionally operate the apparatus for assisting muscular strength so that the apparatus does not generate the force even though the user bends his/her waist while the user wears the apparatus. Thus, the user may take postures, for example, sitting in a chair or on a floor without taking off the apparatus for assisting muscular strength. 
     Referring to  FIGS.  1  and  2   , the apparatus  10  for assisting muscular strength according to an example embodiment of the present disclosure may include: an upper frame  100  configured to be fixed to the user&#39;s upper body; a lower frame  200  disposed below the upper frame  100  and configured to be fixed to the user&#39;s lower body and rotatable relative to the upper frame  100 ; and a wire  300  disposed across the upper frame  100  and the lower frame  200 . Since the lower frame  200  is rotatable relative to the upper frame  100 , the user may walk or bend his/her waist while the user wears the apparatus  10  for assisting muscular strength. Meanwhile, as described below, according to an example embodiment of the present disclosure tension may be applied to the wire  300 , such that the apparatus  10  for assisting muscular strength provides the force for assisting the strength of the user&#39;s waist muscles. Meanwhile, in the present specification and the drawings, for the convenience of description, the relative rotational motions between the upper frame  100  and the lower frame  200  will be described on the basis of a direction in which the lower frame  200  rotates relative to the upper frame  100 . 
     Referring to  FIGS.  1  to  3   , the apparatus  10  for assisting muscular strength according to an example embodiment of the present disclosure may further include a force generating unit  400  coupled to one side of the upper frame  100  and configured to generate the force for assisting the strength of the user&#39;s waist muscles. In more detail, when the lower frame  200  rotates in a first direction D 1  (see  FIGS.  7  to  11   ) relative to the upper frame  100 , the force generating unit  400  may be configured to apply the force to the lower frame  200  in a second direction D 2  (see  FIGS.  7  to  11   ) opposite to the first direction. This configuration may mean that when the user bends his/her waist in the state in which the user wears the apparatus  10  for assisting muscular strength, the force generating unit  400  applies the force in a direction in which the waist is stretched. Therefore, when the user bends his/her waist in the state in which the user wears the apparatus  10  for assisting muscular strength, the user may supplementarily receive the force in the direction in which the waist is stretched. 
     The force generating unit  400  may have a structure in which at least some components of the force generating unit  400  may be configured to be moved in an upward/downward direction H, and the tension of the wire  300  may be changed, thereby changing the force capable of assisting the strength of the waist muscles. 
     Referring to  FIG.  3   , the force generating unit  400  may include: a first movable member  410  configured to be movable in the upward/downward direction H; a second movable member  420  disposed below the first movable member  410  and configured to be movable in the upward/downward direction H; and a main spring part  430  having one side fixed to the first movable member  410  and the other side fixed to the second movable member  420 . Therefore, according to an example embodiment of the present disclosure, as the first and second movable members  410  and  420  are moved in the upward/downward direction H, the deformation amount of the main spring part  430  may be changed, such that the tension of the wire  300  may also be changed. 
     For example, the first and second movable members  410  and  420  may each have a shape having a penetrated central region. Therefore, it is possible to minimize weights of the first and second movable members  410  and  420 .  FIG.  3    illustrates the first and second movable members  410  and  420  each have an approximately quadrangular shape and a penetrated central region. 
     The force generating unit  400  may further include first pulley members  440  fixed to one side of the second movable member  420 . For example, as illustrated in  FIG.  3   , the first pulley members  440  may be fixed to an end of a lower portion of the second movable member  420 . In this case, the wire  300  may extend upward from the lower frame  200 , surround upper portions of the first pulley members  440 , and then extend downward toward the lower frame  200 . 
     According to an example embodiment of the present disclosure, when the second movable member  420  moves downward, the first pulley members  440  may also move downward, such that the wire  300  may also move downward. On the contrary, when the second movable member  420  moves upward, the first pulley members  440  and the wire  300  may also move upward. The upward or downward movement of the second movable member  420  may be initiated by a force of the wire  300  that pulls the second movable member  420  downward. That is, the upward or downward movement of the second movable member  420  may be initiated by the tension of the wire  300 . 
     Meanwhile, referring to  FIG.  3   , the lower frame  200  may include second pulley members  230  coupled to be rotatable relative to the upper frame  100 , and the ends of the wire  300  may be fixed to the second pulley members  230 . 
     According to an example embodiment of the present disclosure, when the lower frame  200  rotates relative to the upper frame  100 , the wire  300  may be wound around or unwound from the second pulley members  230 . Therefore, the first pulley members  440  are moved upward or downward by interference between the wire  300  and the first pulley members  440 . When the first pulley members  440  are moved upward or downward, the second movable member  420  connected to the first pulley members  440  is also moved in the upward/downward direction H, and the first movable member  410  connected to the second movable member  420  by means of the main spring part  430  is also moved in the upward/downward direction H. In this case, when a distance in the upward/downward direction H between the first movable member  410  and the second movable member  420  is changed, the deformation amount of the main spring part  430  is changed, and the tension applied to the wire  300  is changed depending on a change in elastic force of the main spring part  430 . Therefore, according to an example embodiment of the present disclosure, the torque, which is applied by the wire  300  to rotate the second pulley members  230 , is changed by the change in tension applied to the wire  300 , which generates the force for assisting the strength of the user&#39;s waist muscles. 
     Referring to  FIG.  3   , the lower frame  200  may further include a right lower frame  210  configured to be fixed to the user&#39;s right leg, and a left lower frame  220  configured to be fixed to the user&#39;s left leg. In this case, the second pulley members  230  may be respectively disposed on the right and left lower frames  210  and  220 . In addition, the wire  300  may surround a lower region of the second pulley member  230  disposed on the right lower frame  210 , and a lower region of the second pulley member  230  disposed on the left lower frame  220 . This is to allow the wire  300  to be wound around the second pulley members  230  when the right and left lower frames  210  and  220  rotate in a direction toward the upper frame  100 , i.e., when the second pulley members  230  rotate in the first direction D 1 . In this case, as the wire  300  is wound around the second pulley members  230 , the wire  300  pulls the second movable member  420  downward, such that the deformation amount of the main spring part  430  is increased, and thus the tension applied to the wire  300  is increased. Therefore, the wire  300  pulls the second pulley members  230  in the second direction D 2 . 
     In addition, one end of the wire  300  may be fixed to the second pulley member  230  disposed on the right lower frame  210 , and the other end of the wire  300 , which is opposite to one end of the wire  300 , may be fixed to the second pulley member  230  disposed on the left lower frame  220 . Therefore, when both the right and left lower frames  210  and  220  rotate in the direction toward the upper frame  100 , i.e., when the second pulley members  230  rotate in the first direction D 1 , the wire  300  is wound around the second pulley members  230  while the second pulley members  230  rotate, such that the tension of the wire  300  increases. The wire  300  with the increased tension pulls the force generating unit  400  downward by means of the first pulley members  440 , and the deformation amount of the main spring part  430  also increases. Therefore, the force for assisting the strength of the user&#39;s waist muscles, i.e., the force, which rotates the user&#39;s waist in a direction in which the user&#39;s waist is stretched, is increased. As will be described below, this configuration may indicate that when the user bends his/her waist, the force for assisting the strength of the user&#39;s waist muscles, i.e., the force, which is applied in the direction opposite to the direction in which the waist is bent, is increased. 
     Meanwhile, as illustrated in  FIG.  3   , the upper frame  100  may include: an up/down extension region  110  extending in the upward/downward direction H and coupled to the force generating unit  400 ; a right extension region  120  extending in a right direction from a lower portion of the up/down extension region  110  and connected to the right lower frame  210  by means of the second pulley member  230 ; and a left extension region  130  extending in a left direction from the lower portion of the up/down extension region  110  and connected to the left lower frame  220  by means of the second pulley member  230 . In this case, the upper frame  100  may be understood as having an approximately upside-down T shape. 
     According to an example embodiment of the present disclosure, the main spring part  430  may include a plurality of main spring parts. In more detail, as illustrated in  FIG.  3   , the main spring part  430  may include a first main spring part  431  having one end coupled to an upper end region of the first movable member  410 , and the other end coupled to an upper end region of the second movable member  420 . The main spring part  430  may further include a second main spring part  432  having one end coupled to a lower end region of the first movable member  410 , and the other end coupled to a lower end region of the second movable member  420 . 
     In this case, as illustrated in  FIG.  3   , according to an example embodiment of the present disclosure, the lower end region of the first movable member  410  may be disposed between the upper end region of the second movable member  420  and the lower end region of the second movable member  420 . It may be understood that the first movable member  410  is disposed above the second movable member  420  and the first movable member  410  and the second movable member  420  partially overlap each other in the upward/downward direction H. In this case, a length, which is occupied by the first and second movable members  410  and  420  in the upward/downward direction H, may be minimized, which makes it possible to minimize a size of the apparatus  10  for assisting muscular strength. 
     Meanwhile, according to an example embodiment of the present disclosure, the first main spring part  431  or the second main spring part  432  may include a plurality of spring members  430   a . In more detail, the first and second main spring parts  431  and  432  may each include the plurality of spring members  430   a  connected in parallel with each other. 
     In this case, an elastic modulus of the first main spring part  431  and an elastic modulus of the second main spring part  432  may correspond to each other. In this case, the configuration in which the two elastic moduli correspond to each other may be interpreted not only as a configuration in which the two elastic moduli are equal to each other, but also as a configuration in which the two elastic moduli are different from each other to the extent that there is no substantially significant difference, in terms of the performance of the apparatus  10  for assisting muscular strength, from the configuration in which the two elastic moduli are equal to each other. 
     Referring to  FIG.  3   , the upper frame  100  may further include third pulley members  140  respectively fixed to the right and left extension regions  120  and  130 . In this case, the wire  300  may surround lower regions of the third pulley members  140  and then extend upward toward the first pulley members  440 . That is, according to an example embodiment of the present disclosure, the wire  300  may be shaped to i) extend from the second pulley member  230  disposed on the right lower frame  210  to the third pulley member  140  disposed on the right extension region  120 , ii) surround the lower region of the third pulley member  140  disposed on the right extension region  120  and then extend upward, iii) surround upper regions of the first pulley members  440  and then extend downward, and iv) surround the lower region of the third pulley member  140  disposed on the left extension region  130  and then extend to the second pulley member  230  disposed on the left lower frame  220 . 
     Meanwhile, according to an example embodiment of the present disclosure, the upper frame  100  and the force generating unit  400  may be selectively connected or disconnected by the user&#39;s manipulation. To this end, according to an example embodiment of the present disclosure, a latch structure may be rotatably provided. 
     In more detail, referring to  FIG.  3   , the up/down extension region  110  of the upper frame  100  may further include a latch member  112  having a lower region rotatable about an upper region of the latch member  112 . The latch member  112  may face the first movable member  410 . In more detail, the apparatus  10  for assisting muscular strength may be configured such that the lower region of the latch member  112  may be coupled to or separated from the first movable member  410  according to the rotation of the latch member  112 . 
     More particularly, the first movable member  410  may include a recessed portion  412  recessed in a forward/rearward direction. In this case, the recessed portion  412  may be a hole having a penetrated shape or a groove having a recessed shape. For example,  FIG.  3    illustrates that the recessed portion  412  has a penetrated hole shape. 
     In addition, the latch member  112  may include a protrusion  112   a  protruding forward, and the protrusion  112   a  may be inserted into the recessed portion  412  or separated from the recessed portion  412  according to the rotation of the latch member  112 . Therefore, according to an example embodiment of the present disclosure, the up/down extension region  110  and the first movable member  410  may be coupled to each other by the interference between the protrusion  112   a  and the recessed portion  412  when the protrusion  112   a  is inserted into the recessed portion  412 . The up/down extension region  110  and the first movable member  410  may be disconnected from each other when the protrusion  112   a  is separated from the recessed portion  412 . Meanwhile,  FIGS.  5  and  6    illustrate an example in which the protrusion  112   a  protrudes forward from the latch member  112  and the latch member  112  is able to be separated rearward from the first movable member  410  by rotating. In this case, the term “forward” means a direction in which the user is looking when the user wears the apparatus  10  for assisting muscular strength, and the term “rearward” means a direction opposite to the forward direction. 
     According to an example embodiment of the present disclosure, the force generating unit  400  may further include an auxiliary spring part  450  having one end coupled to the up/down extension region  110  and the other end coupled to the first movable member  410 . 
     As described above, the main spring part  430  may be configured to provide the force for assisting the strength of the user&#39;s waist muscles. In contrast, the auxiliary spring part  450  may be configured to provide a predetermined close-contact force that enables the lower frame  200  to come into close contact with the user&#39;s lower body when the user wears the apparatus  10  for assisting muscular strength. In more detail, even when the latch member  112  and the first movable member  410  are decoupled from each other, the auxiliary spring part  450  may be configured to provide a predetermined force that allows the lower frame  200  to rotate away from the upper frame  100 , thereby allowing the lower frame  200  to come into close contact with the user&#39;s lower body. For example, as illustrated in  FIG.  3   , one end of the auxiliary spring part  450  may be fixedly coupled to an upper end of the latch member  112 , and the other end of the auxiliary spring part  450  may be fixedly coupled to an upper end of the first movable member  410 . 
     Meanwhile, since the auxiliary spring part  450  only needs to provide the force for allowing the lower frame  200  to come into close contact with the user&#39;s lower body as described above, an elastic modulus of the auxiliary spring part  450  may be remarkably smaller than an elastic modulus of the first main spring part  431 . 
     Meanwhile, referring to  FIG.  4   , the apparatus  10  for assisting muscular strength according to an example embodiment of the present disclosure may further include a harness  500  coupled to one side of the upper frame  100 . The harness  500  may be configured to surround the user&#39;s chest and shoulders so that the user may more stably wear the apparatus  10  for assisting muscular strength. 
     For example, the harness  500  may include: a first surrounding member  510  configured to surround the user&#39;s chest; a plurality of second surrounding members  520  configured to surround the user&#39;s shoulders; and a handle member  530  having one side extending forward across the user&#39;s shoulders and the other side connected to the upper region of the latch member  112 . 
     The handle member  530  may be configured to couple or decouple latch member  112  to or from the first movable member  410 . In more detail, referring to  FIGS.  5  and  6   , when the user pulls one side of the handle member  530  forward, the upper region of the latch member  112  is rotated, such that the lower region of the latch member  112  may move rearward relative to the upper region which is a rotation axis. When the lower region of the latch member  112  is moved rearward, the first movable member  410  may be moved downward by the tension of the wire  300 , such that the latch member  112  and the first movable member  410  may be moved away from each other in the upward/downward direction. 
       FIG.  7    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength before the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure, and  FIG.  8    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength immediately after the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure.  FIG.  9    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength when the user bends his/her waist in the state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure, and  FIG.  10    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength in the state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure and the latch member and the force generating unit are disconnected from each other. In addition,  FIG.  11    is a view illustrating the relative positional relationships between the components of the force generating unit and the apparatus for assisting muscular strength when the user bends his/her waist in the state in which the user wears the apparatus for assisting muscular strength according to an example embodiment of the present disclosure and the latch member and the force generating unit are disconnected from each other. 
     Hereinafter, a process of operating the apparatus  10  for assisting muscular strength according to an example embodiment of the present disclosure will be described with reference to  FIGS.  7  to  11   . 
     Referring to  FIG.  7   , the lower frame  200  may be maintained in a state in which the lower frame  200  is rotated rearward by a predetermined angle in the second direction D 2  before the user wears the apparatus  10  for assisting muscular strength. Then, when the user wears the apparatus  10  for assisting muscular strength, the lower frame  200  may be rotated forward in the first direction D 1 , as illustrated in  FIG.  8   . In this case, the second pulley members  230  may also be rotated in the first direction D 1  by the rotation of the lower frame  200 , such that the wire  300  is wound around the second pulley members  230 . Therefore, according to the exemplary embodiment, the wire  300  moves the second movable member  420  of the force generating unit  400  downward, such that the main spring part  430  is stretched. When the main spring part  430  is stretched, the tension of the wire  300  is increased by the elastic force of the main spring part  430 . Therefore, the second pulley members  230  receive the force that rotates the second pulley members  230  in the second direction D 2 , and the lower frame  200  also receives the force that rotates the lower frame  200  in the second direction D 2 . These forces act as the forces that bring the lower frame  200  into close contact with the user&#39;s lower body. Then, in example embodiments, when the user bends his/her waist while the user wears the apparatus  10  for assisting muscular strength, the lower frame  200  is rotated at a larger angle in the first direction D 1  relative to the upper frame  100 , as illustrated in  FIG.  9   . Therefore, the wire  300  may be further wound around the second pulley members  230 , and the degree to which the main spring part  430  is stretched is also increased. As a result, in exemplary embodiments, the force, which is applied by the wire to rotate the second pulley members  230  and the lower frame  200  in the second direction D 2 , is also increased. This force may be applied in the direction in which the waist is stretched in the state in which the user bends the waist. Therefore, this force may act as the force for assisting the strength of the user&#39;s waist muscles. 
     In an exemplary embodiment, when the user walks while the user wears the apparatus  10  for assisting muscular strength, the direction in which the right lower frame  210  rotates relative to the upper frame  100  is opposite to the direction in which the left lower frame  220  rotates relative to the upper frame  100 . Therefore, in exemplary embodiments, the direction in which the second pulley member  230  disposed on the right lower frame  210  rotates is opposite to the direction in which the second pulley member  230  disposed on the left lower frame  220  rotates. Therefore, in exemplary embodiments, the force, which is applied by the wire  300  to pull the second movable member  420  downward by means of the first pulley members  440 , is not changed, and the main spring part  430  is not stretched. In exemplary embodiments, the force for assisting the strength of the user&#39;s waist muscles is not additionally generated while the user walks. 
     Meanwhile, according to an example embodiment of the present disclosure, as illustrated in  FIGS.  10  and  11   , the lower frame  200  may come into close contact with the user&#39;s lower body even when the latch member  112  and the first movable member  410  are disconnected from each other. 
     That is, referring to the exemplary embodiment illustrated in  FIG.  10   , since the auxiliary spring part  450  is fixedly coupled to the upper region of the latch member  112  and the first movable member  410 , the auxiliary spring part  450  may still maintain the state in which the second movable member  420  and the first pulley members  440  pull the wire  300  upward, even though the latch member  112  and the first movable member  410  are disconnected from each other. Therefore, in exemplary embodiments, the lower frame  200  still receives the force that rotates the lower frame  200  in the second direction D 2 , such that the lower frame  200  may be kept in close contact with the user&#39;s lower body. 
     In addition, as illustrated in the exemplary embodiment of  FIG.  11   , when the user bends his/her waist while the latch member  112  and the first movable member  410  are disconnected from each other, the auxiliary spring part  450  may be stretched by the tension of the wire  300  while the main spring part  430  is not stretched. In this case, since the elastic modulus of the auxiliary spring part  450  is remarkably smaller than the elastic modulus of the main spring part  430 , the remarkably small amount of force may be applied in the second direction D 2  to the second pulley members  230  or the lower frame  200  even though the auxiliary spring part  450  is stretched to a large extent. Therefore, according to an example embodiment of the present disclosure, the user may sit in a chair or on a floor without receiving the force for assisting the strength of the waist muscles in the state in which the latch member  112  and the first movable member  410  are disconnected from each other. 
     Meanwhile, to reconnect the latch member  112  and the first movable member  410  of the apparatus  10  for assisting muscular strength according to an example embodiment of the present disclosure, the user i) rotates the lower frame  200  rearward in the second direction D 2  so that the wire  300  is unwound from the second pulley members  230  and the force, which is applied by the wire  300  to pull the second movable member  420  downward, is decreased, such that ii) the auxiliary spring part  450  is contracted, iii) the first movable member  410  is moved upward toward the latch member  112 , and thus the latch member  112  and the first movable member  410  may be coupled to each other again. 
     The present disclosure has been described with reference to the limited embodiments and the drawings, but the present disclosure is not limited thereto. The present disclosure may be carried out in various forms by those skilled in the art, to which the present disclosure pertains, within the technical spirit of the present disclosure and the scope equivalent to the appended claims.