Patent Publication Number: US-2023144959-A1

Title: Holder for exercise assistance device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of International Application No. PCT/KR2021/001349 designating the United States, filed on Feb. 2, 2021, in the Korean Intellectual Property Receiving Office and claiming priority to Korean Patent Application No. 10-2020-0078491, filed on Jun. 26, 2020, and Korean Patent Application No. 10-2020-0160035, filed on Nov. 25, 2020, in the Korean Intellectual Property Office, the disclosures of which are all hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     1. Field 
     Certain example embodiments relate to a holder for an exercise assistance device. 
     2. Description of Related Art 
     An exercise assistance device may be a mechanism and/or a device that helps patients or other users, unable to easily walk on their own due to any of various diseases, accidents, and the like, exercise for rehabilitation treatment. In a rapidly aging society, a growing number of people have experienced difficulty exercising normally or inconvenience in exercising, and there is an increasing interest in exercise assistance devices. An exercise assistance device may be worn on a body of a user to help the user exercise by providing a necessary muscular strength that allows the user to walk so that the user may exercise normally. 
     SUMMARY 
     Generally, people who wear an exercise assistance device may have physical disabilities. For these people, the process of putting on an exercise assistance device itself may be difficult. There is need for a holder that holds an exercise assistance device so that a user, e.g., with physical disabilities, may put on the exercise assistance device alone, possibly without the help of other people. 
     The above description is information the inventor(s) acquired during the course of conceiving the present disclosure, or already possessed at the time, and is not necessarily art publicly known before the present application was filed. 
     In an example embodiment, a holder for an exercise assistance device for holding an exercise assistance device may be provided, and the holder may include a main rod, a sliding rod slidable with respect to the main rod, a gripper including a gripper base connected, directly or indirectly, to the sliding rod and configured to support the exercise assistance device, a gripper head connected, directly or indirectly, to an upper side of the gripper base and facing a rear surface of the exercise assistance device, and a gripper arm rotatably connected, directly or indirectly, to the gripper head, and a controller configured to control an operation of the gripper, wherein, when the exercise assistance device is disposed on the gripper base, the gripper base may rotate with respect to the sliding rod and tilt forward, and the controller may move the gripper arm such that at least a portion of the gripper arm may cover a front surface of the exercise assistance device. The holder may include a switch installed on the sliding rod, provided to be in contact with the gripper base when the gripper forms a predetermined angle with respect to the sliding rod, and configured to transmit an on-off signal to the controller, wherein the controller may control an operation of the gripper arm based on the on-off signal. 
     The gripper base may include a base body rotatably connected, directly or indirectly, to the sliding rod and a protruding part protruding from the base body. 
     The gripper may include a gripper spring having one end fixed to the sliding rod and another end fixed to the gripper base and configured to provide a restoring force to the gripper base. 
     The gripper spring may be a torsion spring. 
     The holder may include an angle sensor configured to measure an angle formed by the gripper base with respect to the sliding rod, and the controller may be configured to control an operation of the gripper arm based on angle information measured by the angle sensor. 
     According to an example embodiment, a holder for an exercise assistance device for holding an exercise assistance device may be provided, and the holder may include a main rod, a sliding rod slidable with respect to the main rod, a gripper connected, directly or indirectly, to the sliding rod and configured to support the exercise assistance device, a gravity compensation part provided inside the main rod and slidable along the main rod while supporting the sliding rod, and a gravity compensation spring having an upper end fixed to the main rod and a lower end fixed to the gravity compensation part. 
     The gravity compensation part may be in close contact with an inner side surface of the main rod such that the gravity compensation spring may remain in a deformed state. 
     The gravity compensation part may include a slider configured to support the sliding rod and having an accommodation space therein, a core part provided in the accommodation space of the slider, a moving part movable with respect to the slider in a direction perpendicular to a longitudinal direction of the main rod and provided to be in close contact with an inner side surface of the main rod, and a sub-spring configured to connect the core part and the moving part. 
     The slider may include a slider hole penetrating in a direction perpendicular to the longitudinal direction of the main rod, and the moving part may be movable along the slider hole. 
     The moving part may include a moving body connected, directly or indirectly, to the sub-spring and one or more of moving wheels rotatably installed on the moving body and provided to be in contact with the inner side surface of the main rod. 
     One or more of the moving wheel(s) may include a first moving wheel and a second moving wheel, and the sub-spring may be connected, directly or indirectly, to the moving body between the first moving wheel and the second moving wheel. 
     While being in surface contact with the inner side surface of the main rod, one or more of the moving wheels may move along the inner side surface of the main rod. 
     A plurality of moving parts may be provided, and the plurality of moving parts may be spaced apart from each other at regular intervals in a circumferential direction of the core part. 
     The holder for the exercise assistance device may include a contact ring provided on an upper end of the main rod and contacting a sliding rod. 
     According to an example embodiment, a holder for an exercise assistance device for holding an exercise assistance device may be provided, and the holder may include a main rod, a sliding rod slidable with respect to the main rod, a gripper connected, directly or indirectly, to the sliding rod and configured to support the exercise assistance device, and a mounting guider including a guider body installed on the sliding rod, a damper connected, directly or indirectly, to the guider body, a damper gear rotatably connected, directly or indirectly, to the damper, a driving gear engaging with the damper gear, a first rod connected, directly or indirectly, to the driving gear in parallel with a rotation axis of the driving gear, and a second rod extending from the first rod in a direction intersecting with a longitudinal direction of the first rod. 
     The driving gear may include an engaging part in which gear teeth that engage with the damper gear are formed and an idling part that does not engage with the damper gear. 
     In a state in which no external force is applied to the second rod, the second rod may face vertically downward, and the driving gear may engage with the damper gear. 
     While the second rod rotates in a direction toward the exercise assistance device, a part of the driving gear that faces the damper gear may be switched from the engaging part to the idling part. 
     The mounting guider may further include a guider housing configured to accommodate the damper gear and the driving gear, and the holder for the exercise assistance device may further include a guider spring having one end fixed to the guider housing and another end fixed to the driving gear. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the present disclosure will be more apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    is a front view of a holder for an exercise assistance device according to an example embodiment. 
         FIG.  2    is a side view of a holder for an exercise assistance device according to an example embodiment. 
         FIG.  3    is a side view illustrating an exercise assistance device that is disposed on a gripper according to an example embodiment. 
         FIG.  4    is a block diagram of a switch, a controller, and a gripper arm according to an example embodiment. 
         FIG.  5    is a plan view of a cradle and an exercise assistance device of  FIG.  3    viewed from above. 
         FIG.  6    is a side view schematically illustrating a user wearing an exercise assistance device that is disposed on a gripper according to an example embodiment. 
         FIG.  7    is a plan view of a cradle and an exercise assistance device of  FIG.  7    viewed from above. 
         FIG.  8    is a side view illustrating an exercise assistance device that is disposed on a gripper according to an example embodiment. 
         FIG.  9    is a cross-sectional view and a partially enlarged view of a holder for an exercise assistance device according to an example embodiment. 
         FIG.  10    is a cross-sectional view of a gravity compensation part according to an example embodiment. 
         FIG.  11    is a cross-sectional view of a gravity compensation part that is cut at an angle different from an angle of  FIG.  10    according to an example embodiment. 
         FIG.  12    is a front view schematically illustrating a mounting guider that is partially cut according to an example embodiment. 
         FIGS.  13 - 15    are side views and partially enlarged views schematically illustrating a user wearing an exercise assistance device that is disposed on a holder for an exercise assistance device and moving forward according to an example embodiment(s). 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed structural or functional description is provided as an example only and various alterations and modifications may be made to the examples. Here, example embodiments are not to be construed as limited to the disclosure and should be understood as including all changes, equivalents, and replacements within the idea and the technical scope. 
     Terms, such as first, second, and the like, may be used herein to describe various components. Each of these terms is not used to define an essence, order or sequence of a corresponding component but is used merely to distinguish the corresponding component from other component(s). For example, a “first” component may be referred to as a “second” component, and similarly, the “second” component may be referred to as the “first” component. 
     It should be noted that if one component is described as being “connected”, “coupled”, or “joined” to another component, a third component(s) may be “connected”, “coupled”, and “joined” between the first and second components, although the first component may be directly connected, coupled, or joined to the second component. 
     The singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises/comprising” and/or “includes/including” when used herein, 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. 
     The same name may be used to describe an element included in the example embodiments described above and an element having a function in common. Unless otherwise mentioned, the descriptions of the example embodiments may be applicable to the following example embodiments and thus, duplicated descriptions will be omitted for conciseness. 
     Unless otherwise defined, all terms, including technical and scientific terms, used herein have the same meaning as is commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms, such as those defined in commonly used dictionaries, are to be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art, and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     Hereinafter, example embodiments will be described in detail with reference to the accompanying drawings. When the example embodiments are being described with reference to the accompanying drawings, like reference numerals refer to like elements and any repeated description related thereto has been omitted. 
       FIG.  1    is a front view of a holder for an exercise assistance device according to an example embodiment, and  FIG.  2    is a side view of a holder for an exercise assistance device according to an example embodiment. 
     Referring to  FIGS.  1  and  2   , a holder  100  for an exercise assistance device may support an exercise assistance device (not shown) for assisting a user in exercising. For example, the exercise assistance device may be a walking assistance device that may assist the user in walking. For example, the holder  100  for the exercise assistance device may support the exercise assistance device that assists the user in walking. For example, the holder  100  for the exercise assistance device may support the exercise assistance device by separating the exercise assistance device upward from a ground, for example, by separating the exercise assistance device from the ground to a proper extent such that the exercise assistance device is positioned at a right height for a height of the user. 
     The holder  100  for the exercise assistance device may include a main base  190  seated on the ground, a main rod  110  extending upward from the main base  190 , a sliding rod  120  slidably connected, directly or indirectly, to the main rod  110 , a gripper  1  installed on an upper end of the sliding rod  120 , a gravity compensation part (not shown) provided inside the main rod  110  and supporting the sliding rod  120 , and a mounting guider  3  installed on the sliding rod  120  and positioned below the gripper  1 . 
     An area on which the main base  190  is seated may be larger than an area on which the main rod  110  is seated such that the holder  100  for the exercise assistance device may remain in its pose while supporting the exercise assistance device. Although the drawings illustrate that the main base  190  is a square-shaped plate, the shape of the main base  190  is not limited thereto. For example, the main base  190  may have different shapes, for example, circular or oval, or may be a plurality of branched rods. 
     The sliding rod  120  may slide in a longitudinal direction, that is, a z-axis direction, of the main rod  110 . Although the drawings illustrate that the main rod  110  has a sliding space therein and that the sliding rod  120  is slidably inserted into the main rod  110 , examples are not limited thereto. For example, the sliding rod  120  may have a sliding space therein, and the main rod  110  may be slidably inserted into the sliding rod  120 . 
     The gripper  1  may support a part of the wearable device (e.g., exercise assistance device) that supports a back of the user. The mounting guider  3  may be inserted into an inner space of a thigh band of the exercise assistance device that encloses a thigh of the user and may set a position of the thigh band. 
     The gripper  1  may include a gripper base  11  rotatably connected, directly or indirectly, to the sliding rod  120 , a gripper head  12  connected, directly or indirectly, to an upper side of the gripper base  11  and facing a rear surface of the exercise assistance device, a gripper arm  13  rotatably connected, directly or indirectly, to the gripper head  12 , and a controller  17  that controls an operation of the gripper arm  13 . The controller  17  may be provided on the gripper head  12 , but examples are not limited thereto. For example, the controller  17  may be provided on the sliding rod  120  or the main rod  110 . 
     When the exercise assistance device is disposed on the gripper base  11 , the gripper base  11  may rotate with respect to the sliding rod  120  and tilt forward. In other words, the gripper base  11  may rotate around a y-axis in a counterclockwise direction. The controller  17  may recognize the gripper base  11  is tilting and move the gripper arm  13  such that at least a portion of the gripper arm  13  may cover a front surface of the exercise assistance device. 
     The gripper arm  13  may prevent or reduce the chance of the wearable device (e.g., exercise assistance device) from falling forward (e.g., in a +x direction). Even if the holder  100  for the exercise assistance device receives an impact, since the gripper arm  13  may cover the front surface of the exercise assistance device, separation of the exercise assistance device from the holder  100  for the exercise assistance device may be prevented or reduced. 
       FIG.  3    is a side view illustrating an exercise assistance device that is disposed on a gripper according to an example embodiment,  FIG.  4    is a block diagram of a switch, a controller, and a gripper arm according to an example embodiment, and  FIG.  5    is a plan view of a cradle and an exercise assistance device of  FIG.  3    viewed from above. 
     Referring to  FIGS.  3  through  5   , a holder for an exercise assistance device may further include a switch  130  installed on the sliding rod  120 . The switch  130  may contact the gripper base  11  while the gripper base  11  rotates. The switch  130  may transmit an electrical signal to the controller  17 . For example, the switch  130  may include a button and transmit an on-off signal to the controller  17  according to whether the button is pressed. 
     While a main body D of the exercise assistance device is disposed on the gripper base  11 , the gripper base  11  may tilt forward. In other words, the gripper base  11  may rotate around an axis provided at the sliding rod  120 . Here, the main body D may be a part of the exercise assistance device that faces a back portion of the user. 
     While the main body D of the exercise assistance device is disposed on the gripper base  11 , the switch  130  may contact the gripper base  11  and transmit an on signal to the controller  17 . Meanwhile, while the main body D of the exercise assistance device is disposed on the gripper base  11 , the switch  130  may be spaced apart from the gripper base  11  and transmit an off signal to the controller  17 . In response to a signal transmitted from the switch  130  being switched, the controller  17  may control an operation of the gripper arm  13 . 
     For example, the gripper base  11  may include a base body  111  rotatably connected, directly or indirectly, to the sliding rod  120 , a protruding part  112  protruding from the base body  111 , and a finger  113  connected, directly or indirectly, to a lower end of the base body  111 . 
     The protruding part  112  may interfere with the switch  130  while the base body  111  rotates. The switch  130  is illustrated positioned in front (a +x direction) of the protruding part  112 , but examples are not limited thereto. For example, the switch  130  may be positioned behind (a −x direction) the protruding part  112 . 
     The finger  113  may be installed on a lower side of the base body  111  to have an adjustable angle. For example, an angle of the finger  113  may be adjusted based on an axis parallel to a rotation axis of the base body  111 . The angle of the finger  113  may be adjusted according to a size of the main body D of the exercise assistance device. 
     The gripper arm  13  may include an arm body  131  rotatably connected to the gripper head  12  and an arm head  132  formed on an end of the arm body  131 . The arm head  132  may be rounded and may directly contact the main body D of the exercise assistance device. The arm head  132  may be positioned in front (the +x direction) of the main body D and support the main body D to prevent or reduce the chance of the main body D from falling outwards. 
     The gripper may include a gripper spring  15  having one end fixed to the sliding rod  120  and another end fixed to the gripper base  11  and providing a restoring force to the gripper base  11 . The gripper spring  15  may be, for example, a torsion spring. The gripper spring  15  may assist in restoring the gripper base  11  to its initial state when an external force is removed. 
       FIG.  6    is a side view schematically illustrating a user wearing an exercise assistance device that is disposed on a gripper according to an example embodiment, and  FIG.  7    is a plan view of a cradle and an exercise assistance device of  FIG.  7    viewed from above. 
     Referring to  FIGS.  6  and  7   , when a user puts on an exercise assistance device mounted on a holder for the exercise assistance device, the main body D of the exercise assistance device may be pushed backward (in a −x direction) by a back U of the user. In this example, the gripper base  11  may rotate around a rotation axis in a clockwise direction, and the protruding part  112  of the gripper base  11  may contact the switch  130 . The switch  130  may transmit an on signal to the controller  17 , and the controller  17  may control an operation of the gripper arm  13  such that the gripper arm  13  moves outward. As a result, the gripper arm  13  may no longer cover the front face of the main body D. The user may move forward while wearing the exercise assistance device. 
     The switch  130  is previously described as being positioned in front of the protruding part  112 , but the position of the switch  130  is not limited thereto. For example, the switch  130  may be positioned behind the protruding part  112 , and in this case, the switch  130  may contact the protruding part  112  and transmit an on signal to the controller  17  while the main body D of the exercise assistance device is disposed on the gripper base  11 . 
       FIG.  8    is a side view illustrating an exercise assistance device that is disposed on a gripper according to an example embodiment. 
     Referring to  FIG.  8   , a gripper may include an angle sensor  18  that may measure an angle formed by the gripper base  11  with respect to the sliding rod  120 . The angle sensor  18  may transmit angle information to the controller  17 , and the controller  17  (comprising processing circuitry) may control an operation of the gripper arm  13  based on the angle information sensed by the angle sensor  18 . 
       FIG.  9    is a cross-sectional view and a partially enlarged view of a holder for an exercise assistance device according to an example embodiment.  FIG.  10    is a cross-sectional view of a gravity compensation part according to an example embodiment, and 
       FIG.  11    is a cross-sectional view of a gravity compensation part that is cut at an angle different from an angle of  FIG.  10   . 
     Each embodiment herein may be used in combination with any other embodiment(s) described herein. 
     Referring to  FIGS.  9  through  11   , a holder for an exercise assistance device may include the main rod  110 , the sliding rod  120  that may slide with respect to the main rod  110 , a gripper (not shown) that is connected to the sliding rod  120  and may support the exercise assistance device, a gravity compensation part  2  that is provided inside the main rod  110  and may slide along the main rod  110  while supporting the sliding rod  120 , a gravity compensation spring  170  having an upper end fixed to the main rod and a lower end fixed to the gravity compensation part  2 , and a contact ring  180  that is provided on an upper end of the main rod  110  and contacts the sliding rod  120 . The contact ring  180  may include, for example, polytetrafluoroethylene (PTFE), also known as Teflon, and the like. 
     The gravity compensation spring  170  may remain stretched while the exercise assistance device is disposed on the gripper (not shown) and help the user lift up the exercise assistance device that is disposed on the gripper using a small force by providing a restoring force to the gravity compensation part  2 . 
     The gravity compensation part  2  may include a slider  21  that supports the sliding rod  120  and has an accommodation space S therein, a core part  24  that is provided in the accommodation space of the slider  21 , a moving part  22  that may move with respect to the slider  21  and be in close contact with an inner side surface of the main rod  110 , and a sub-spring  25  that connects the core part  24  and the moving part  22 . The moving part  22  may move with respect to the slider  21  in a direction perpendicular to a longitudinal direction of the main rod  110 . A plurality of moving parts  22  and sub-springs  25  may be provided to enclose the core part  24 . The sub-spring  25  in a compressed state may be provided between the core part  24  and the moving part  22 . 
     The moving parts  22  may be spaced apart from each other at a predetermined interval in a circumferential direction of the core part  24 . For example, as illustrated in the drawings, four moving parts  22  may be provided and spaced apart from each other at 90-degree intervals in the circumferential direction of the core part  24 . As another example, two, three, or five or more moving parts  22  may be provided. Based on such a structure, the gravity compensation part  2  may be stably in close contact with an inner side surface of the main rod  110 . 
     The slider  21  may include a slider hole  21   a  penetrating in a direction perpendicular to a longitudinal direction of the main rod  110 , and the moving part  22  may move along the slider hole  21   a.    
     The moving part  22  may include a moving body  221  that is connected, directly or indirectly, to the sub-spring  25  and one or more of moving wheels  222  that are rotatably installed on the moving body  221  and contact the inner side surface of the main rod  110 . One or more of the moving wheels  222  may include a first moving wheel and a second moving wheel that are spaced apart in a longitudinal direction of the moving body  221 , and the sub-spring  25  may be connected to the moving body  221  between the first moving wheel and the second moving wheel. Based on such a structure, an elastic force transmitted from the sub-spring  25  may be evenly distributed to the first moving wheel and the second moving wheel. 
     The moving wheel  222  may move along the inner side surface of the main rod  110  while being in surface contact with the inner side surface of the main rod  110 . For example, a part of the inner side surface of the main rod  110  that faces the moving wheel  222  may be flat. As another example, when an inner side hollow space of the main rod  110  is completely cylindrical, the moving wheel  222  may be curved, the curvature corresponding to the inner side surface of the main rod  110  to be in surface contact with the inner side surface of the main rod  110 . For example, the moving wheel  222  may have a rubber pad on an outer surface to increase a contact area. 
       FIG.  12    is a front view schematically illustrating a mounting guider that is partially cut according to an example embodiment.  FIGS.  13  through  15    are side views and partially enlarged views schematically illustrating a user putting on an exercise assistance device that is disposed on a holder for an exercise assistance device and moving forward according to an example embodiment. 
     Referring to  FIGS.  12  and  13   , a holder for an exercise assistance device may be mounted on or include the sliding rod  120  and include a mounting guider  3  that helps a user easily put a thigh band B of the exercise assistance device around his or her thigh, the thigh band B having elasticity. 
     The mounting guider  3  may provide a relatively rigid support to the thigh band B for a predetermined period from a time point at which the user starts to move forward while putting on the exercise assistance device. Through such a mechanism, the mounting guider  3  may assist the user who is moving forward while putting on the exercise assistance device causing the thigh band B to stretch. Meanwhile, when the user moves forward farther than a predetermined point, the mounting guider  3  may separate from the thigh band B, and a restoring force may provide the thigh band B with the ability to wind around the thigh of the user. 
     The exercise assistance device may include the main body D that supports a back of the user, a torso frame F 1  worn on a torso of the user, an actuator A disposed on the torso frame F 1 , a thigh frame F 2  that rotates by receiving power from the actuator A, and the thigh band B connected to the thigh frame F 2  and worn around the thigh of the user. 
     The thigh band B may have elasticity. While the main body D is seated on the gripper  1  of a cradle, the mounting guider  3  may be provided inside the thigh band B. When the user moves forward while putting on the torso frame F 1  and positioning a thigh inside the thigh band B, the thigh band B may be stretched while in a state of being engaged with the mounting guider  3 . When the user moves forward farther than a predetermined distance, the thigh band B may separate from the mounting guider  3 , and the restoring force may provide the thigh band B with the ability to wind around the thigh of the user. 
     The mounting guider  3  may include a guider body  31  installed on the sliding rod  120 , a damper  32  connected to the guider body  31 , a damper gear  35  rotatably connected, directly or indirectly, to a drive shaft  34  of the damper  32 , a driving gear  36  engaging with the damper gear  35 , a first rod  37  connected to the driving gear  36  in parallel with a rotation axis of the driving gear  36 , and a second rod  39  extending from the first rod  37 . The mounting guider  3  may include a guider housing  33  that accommodates the damper gear and the driving gear  36  and a guider spring  38  provided between the guider housing  33  and the driving gear  36 . 
     In a state in which no external force is being applied to the second rod  39 , the second rod  39  may face downward due to gravity. 
     The driving gear  36  may include an engaging part  361  in which gear teeth that engage with the damper gear  35  are formed and an idling part  362  that does not engage with the damper gear  35 . Based on a circumference of the driving gear  36 , for example, a sector with a 300-degree central angle may be the engaging part  361 , and a remaining sector with a 60-degree central angle may be the idling part  362 . Meanwhile, gear teeth may be formed around the entire damper gear  35 . 
     While not being pulled by the thigh band B, the second rod  39  may face vertically downward, and the engaging part  361  may engage with the damper gear  35 . In this example, a central angle of a sector Θ 1  formed by two radii and an arc from a point at which the driving gear  36  engages with the damper gear  35  counterclockwise to a point at which the idling part  362  starts may be, for example, 30 degrees. A central angle of a sector Θ 2  formed by the idling part  362  may be, for example, 60 degrees. When the user moves forward while putting on the exercise assistance device, the second rod  39  may be pulled by the thigh band B, and the driving gear  36  may rotate in a clockwise direction. In the sector Θ 1 , the driving gear  36  may rotate while engaging with the damper gear  35 , and resistance to the rotation of the driving gear  36  may be generated by the damper  32 . Based on such a structure, when the user moves forward, the thigh band B may be stretched, and potential energy of the thigh band B may increase. 
     When the user moves forward a distance more than a predetermined distance, a part of the driving gear  36  that faces the damper gear  35  may be switched from the engaging part  361  to the idling part  362 , and the driving gear  36  may rotate quickly without the resistance generated by the damper  32 . In this example, the thigh band B may separate from the second rod  39  and contract in a direction toward the thigh of the user. 
     Even if the second rod  39  rotates in a clockwise direction due to inertia, the part of the driving gear  36  that faces the damper gear  35  may be switched from the idling part  362  to the engaging part  361 , and rotational force of the driving gear  36  may be gradually reduced due to the resistance generated by the damper  32 . 
     The guider spring  38  may assist in restoring the second rod  39  to its initial pose. One end of the guider spring  38  may be fixed to the guider housing  33 , and another end of the guide spring  38  may be fixed to the driving gear  36 . For example, the guider spring  38  may be in an initial state in which it is not deformed while the second rod  39  faces vertically downward and may have minimum or small potential energy. For example, the guider spring  38  may be deformed while the driving gear  36  rotates and provide a restoring force to the driving gear  36  such that the second rod  39  may face vertically downward again and stay in its position. 
     As described above, although the example embodiments have been described with reference to the limited drawings, a person skilled in the art may apply various technical modifications and variations based thereon. For example, suitable results may be achieved if the described techniques are performed in a different order and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents. 
     While the disclosure has been illustrated and described with reference to various embodiments, it will be understood that the various embodiments are intended to be illustrative, not limiting. It will further be understood by those skilled in the art that various changes in form and detail may be made without departing from the true spirit and full scope of the disclosure, including the appended claims and their equivalents. It will also be understood that any of the embodiment(s) described herein may be used in conjunction with any other embodiment(s) described herein. 
     Therefore, other implementations, other example embodiments, and/or equivalents of the claims are within the scope of the following claims.