Patent Publication Number: US-9415262-B2

Title: Handgrip

Description:
TECHNICAL FIELD 
     The present invention relates to a handgrip, and more particularly, to a handgrip having a structure capable of considerably increasing a resilient force acting between right and left arms, and being easily manufactured. 
     BACKGROUND ART 
     A handgrip is a kind of exercise equipment used to train muscle strength of a hand or a forearm, and includes one pair of arms and a spring which applies a force in a direction disturbing an approaching motion of the arms. 
     Using the handgrip, a user repeatedly performs a motion which applies a force and approaches the arms while overcoming the resilient force provided by the spring, and a motion which releases the force and turns the arms to their original positions, thereby increasing the muscle strength of his/her hand or forearm. 
     There has been disclosed a conventional handgrip which includes one pair of arms and a spring of which both ends are fixed to the right and left arms, respectively, and a center portion is formed in a coil shape. However, since the conventional handgrip has a constant intensity of the resilient force provided by the spring, it is impossible to change strength of the handgrip, i.e., the intensity of the resilient force provided by the spring. 
     To solve such a disadvantage of the conventional handgrip, in Korean Patent No. 0760083 granted to the applicant of the present invention, there has been disclosed a handgrip capable of controlling the intensity of the resilient force. 
     The handgrip capable of controlling the intensity of the resilient force includes one pair of first and second arms of which upper portions are rotatably coupled to each other by a rotating shaft, a spring guide having a first guide supported by a pin so as to rotate toward an inside of the first arm and a second guide coupled to the first guide so as to move in a lengthwise direction, and a spring which is disposed between the first and second guides of the spring guide. The second guide is formed so that a position of an end thereof may move up and down in an inside of the second arm, and thus a position of the spring may be changed, and the intensity of the resilient force may be controlled. 
     The handgrip capable of controlling the intensity of the resilient force, as described above, has an advantage that a user can adjust the intensity of the resilient force in accordance with his/her muscle strength, but also has a disadvantage that it is limited in providing a high intensity for an athlete. 
     First, since the spring is located between insides of the one pair of arms, there is a limitation in adding a spring or increasing a size of the spring. 
     Second, the arms are formed of a plastic material using a mold, and, as the strength of the spring is increased, the arms formed of the plastic material may not sufficiently support the resilient force. To solve such disadvantages, a metallic material may be used, but there is another problem that a manufacturing cost is increased. 
     That is, the metallic material may ensure a sufficient supporting force due to its own strength, even when it has a simple shape, and thus a simple manufacturing method other than a method using the mold, which can reduce a cost, is required. 
     Due to such disadvantages, the handgrip used for an ordinary person&#39;s casual exercise may control the intensity of the resilient force. However, in the case of the handgrip having the high intensity for the athlete, the center portion thereof still includes the coil-shaped spring. 
     However, since the handgrip having the high intensity may not control the intensity of the resilient force, separate handgrips should be used according to their intensities, and also as a thickness of a spring wire is increased, the right and left arms are not arranged on the same plane, but may be twisted from each other, and thus a grip feeling may be deteriorated. 
     DISCLOSURE 
     Technical Problem 
     The present invention is directed to providing a handgrip in which spring members are installed on front and back sides of right and left arms, respectively, so as to provide a high intensity of a resilient force, and a design thereof is easily changed to increase the resilient force of the spring members, and also which is easily manufactured. 
     Technical Solution 
     One aspect of the present invention provides a handgrip including right and left arms in which upper portions thereof are coupled to each other by a rotating shaft so as to rotate around the rotating shaft, thereby approaching each other and being spaced apart from each other, and lower portions thereof are held by a user&#39;s hand, and a resilient means for providing a resilient force in the direction obstructing the approaching of the right and left arms, wherein the resilient means includes spring members symmetrically installed on front and back sides of the upper portions of the right and left arms, respectively, and each of the front and back side spring members includes a compression spring, and right and left spring support portions in which the compression spring is interposed therebetween to be supported in a compressible manner, and each of the left spring support portions and the right spring support portions of the front and back side spring members is connected to each other by left and right spring member coupling shafts, while the upper portion of the left arm or the upper portion of the right arm is interposed therebetween, and is operated in an integrated manner. 
     The left arm may include a cylindrical left grip disposed at a lower portion thereof, and a left plate body disposed at an upper portion thereof and configured in a plate coupled with the left grip, and the right arm may include a cylindrical right grip disposed at a lower portion thereof, and a right plate body disposed at an upper portion thereof and configured in a plate coupled with the right grip. 
     The right arm may further include front and back side connecting plates which are coupled to front and back sides of the right plate body, respectively, and of which upper ends extend left so as to interpose an upper end of the left plate body therebetween, and the left plate body is interposed between the front and back side connecting plates and then rotatably coupled therewith by the rotating shaft installed to pass therethrough. And an arc-shaped sliding surface centering on the rotating shaft may be formed at a right upper end surface of the left plate body, and a corresponding sliding surface having a corresponding shape and engaged with the sliding surface to be slidably rotated may be formed at a left upper end surface of the right plate body. 
     The left and right plate bodies and the front and back side connecting plates may be manufactured by cutting a plate material formed of a metallic material, and the left and right grips may be formed of a metal rod. 
     The left spring member coupling shaft configured to connect the left spring support portions of the front and back side spring members may be rotatably installed through a coupling shaft through-hole formed at the left plate body, and the right spring member coupling shaft configured to connect the right spring support portions of the front and back side spring members may be installed at a left surface of the right plate body to be movable in a lengthwise direction. 
     A plurality of resilient force control grooves may be formed at a left surface of the upper portion of the right arm in the lengthwise direction, and a middle portion of the right spring member coupling shaft may be coupled to one of the resilient force control grooves so as to control an intensity of the resilient force. 
     A stop member disposed between the front and back side connecting plates coupled to the front and back sides of the right plate body, respectively, and rotatably coupled to the front and back side connecting plates to be rotated around a hinge shaft, and having a left end contact surface which is in contact with a contact part formed at a left end thereof to be directed to an upper end of the left plate body may be disposed at an upper surface of the right plate body, and the stop member may have a restriction position in which the left end contact surface is disposed to be in contact with the contact part and thus to restrict a rotation between the left and right arms within a predetermined range, and a control position in which the stop member is deviated from the restriction position by rotating around the hinge shaft, and the left and right arms are allowed to be rotated with respect to each other to a position in which the resilient force of the spring members is not applied. 
     An elastic pressing part configured to press a lower surface of the stop member may be further formed at the upper surface of the right plate body, such that the stop member is prevented from being freely rotated by its own weight. And the elastic pressing part may include a spring installed at an inside of a spring installing groove formed at the upper surface of the right plate body, and a bead-shaped locking ball elastically supported by the spring so as to press the lower surface of the stop member, and a plurality of catching grooves to which the locking ball is coupled may be formed at the lower surface of the stop member. 
     Advantageous Effects 
     According to the handgrip of the present invention having the above-described structure, since the spring members are provided on the front and back sides of the right and left arms, respectively, and thus at least one pair of spring members are installed, it is possible to provide the high intensity of the resilient force. Further, since the spring members are disposed at an outside, and are not interfered with other structures, a thickness and a wound diameter of a spring wire can be controlled according to design strength, and thus it is advantageous in providing the handgrip having the high intensity. 
     Also, according to the present invention, since plate members manufactured in a cutting manner of a plate material formed of a metallic material through laser processing or press processing are used as main elements, the main elements can be easily manufactured, and also since the grip part formed of the metal rod can be easily manufactured, a manufacturing cost is low, compared with a molding manner using a mold, and the handgrip can be easily manufactured. 
     Therefore, according to the present invention, the handgrip which has the low manufacturing cost and the high intensity and in which the resilient force can be controlled can be provided. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a handgrip according to one embodiment of the present invention. 
         FIG. 2  is an exploded view of the handgrip illustrated in  FIG. 1 . 
         FIG. 3  is a view illustrating a front and back side connecting plate of the handgrip according to one embodiment of the present invention. 
         FIG. 4  is a view illustrating a stop member of the handgrip according to one embodiment of the present invention. 
         FIG. 5  is a perspective view illustrating a coupled state of a spring member of the handgrip according to one embodiment of the present invention. 
         FIG. 6  is a cross-sectional view taken along line A-A′ of the spring member illustrated in  FIG. 5 . 
         FIG. 7  is a cross-sectional view of the assembled handgrip according to one embodiment of the present invention. 
         FIG. 8  is a partial cross-sectional view illustrating a handgrip according to another embodiment of the present invention, in which a structure related to the stop member is modified. 
         FIG. 9  is an exploded view illustrating still another embodiment of the present invention, in which left and right arms are modified. 
         FIG. 10  is a view illustrating a coupled state of the handgrip illustrated in  FIG. 9 . 
         FIG. 11  is a cross-sectional view illustrating an operation of the stop member for adjusting a resilient force in the handgrip according to one embodiment of the present invention. 
         FIG. 12  is a cross-sectional view illustrating an operation of controlling the resilient force by controlling a position of the spring member in the handgrip according to one embodiment of the present invention. 
     
    
    
     MODES OF THE INVENTION 
     Hereinafter, exemplary embodiments of a handgrip according to the present invention will be described in detail with reference to the accompanying drawings. 
     Referring to  FIGS. 1 to 7 , the handgrip according to the present invention includes one pair of arms  10  and  20  including a left arm  10  and a right arm  20 , and one pair of spring members  50   a  and  50   b  symmetrically installed on front and back sides of the left and right arms  10  and  20 , respectively and connected to each other. 
     Upper portions of the left and right arms  10  and  20  are coupled to each other by a rotating shaft  35  so as to rotate around the rotating shaft  35 , thereby approaching each other and being spaced apart from each other. 
     The left arm  10  includes a left grip  12  configured to form a lower portion thereof, and a left plate body  14 . 
     The left grip  12  is formed of a cylindrical metal rod in which a coupling hole  13  is formed at a center of an upper end thereof in a lengthwise direction. 
     The left plate body  14  is manufactured of a plate material formed of a metallic material which is machined through laser processing, press processing, or the like, and a coupling part  15  inserted and coupled into the coupling hole  13  of the left grip  12  is formed at a lower end thereof. Also, the left plate body  14  has a shape which is bent and extends in a right-upward direction. 
     A rotating shaft coupling hole  19  is formed to pass through an upper portion of the left plate body  14  in a front and rear direction, and a sliding surface  16  having an arc shape centering on the rotating shaft coupling hole  19  is formed at an right upper end surface of the left plate body  14 , and a contact part  17  which is in contact with a stop member  40  is formed so as to protrude upward toward an upper side of the sliding surface  16 . 
     The left plate body  14  is disposed between the spring members  50   a  and  50   b , and a coupling shaft through-hole  18  is formed at a left surface of a lower portion thereof. Left spring support portions  51   a  of the front and back side spring members  50   a  and  50   b  are connected with each other by a left spring member coupling shaft  57  passing through the coupling shaft through-hole  18 , while the left plate body  14  is interposed therebetween. 
     The right arm  20  includes a right grip  22  configured to form a lower portion thereof, a right plate body  24 , and front and back side connecting plates  30   a  and  30   b.    
     Like the left grip  12 , the right grip  22  is formed of a cylindrical metal rod in which a coupling hole  23  is formed at a center of an upper end thereof in a lengthwise direction. 
     Like the left plate body  14 , the right plate body  24  is manufactured of a plate material formed of a metallic material which is machined through the laser processing, the press processing, or the like, and a coupling part  25  inserted and coupled into the coupling hole  23  of the right grip  22  is formed at a lower end thereof. Also, the right plate body  24  has a shape which is bent and extends upward. 
     A correspondingly shaped, i.e., concave arc-shaped corresponding sliding surface  26  which is engaged with the arc-shaped sliding surface  16  so as to be slidably rotated is formed at a left upper end surface of the right plate body  24 . Therefore, when the left arm  10  and the right arm  20  are rotated around the rotating shaft  35 , a sliding motion occurs between the sliding surface  16  and the corresponding sliding surface  26 , and thus an action force is dispersed. Therefore, unlike a manner supported by only the rotating shaft  35 , there is no risk to be damaged, even when a high intensity of the resilient force is applied. 
     A plurality of resilient force control grooves  27  formed to have semicircular cross sections in a lengthwise direction are formed at a left surface of the right plate body  24  which faces the left plate body  14 . Connecting plate fixing holes  28  through which a fixing member  34  for fixing the front and back side connecting plates  30   a  and  30   b  passes to be inserted therein are formed at surfaces of upper and lower sides thereof. 
     The front side connecting plate  30   a  and the back side connecting plate  30   b  are disposed and fixed to front and back sides of the right plate body  24 , respectively. The front side connecting plate  30   a  and the back side connecting plate  30   b  are manufactured of a plate material formed of a metallic material machined by the laser processing, the pressing processing or the like, and formed to be symmetric to each other. 
     The front and back side connecting plates  30   a  and  30   b  are fixed together to the right plate body  24  by the fixing member  34  which passes through the connecting plate fixing holes  28  of the right plate body  24  so as to fix the front and back side connecting plates  30   a  and  30   b , and fixing holes  32  are formed at positions corresponding to the connecting plate fixing holes  28 . 
     Upper ends of the front and back side connecting plates  30   a  and  30   b  extend left so that an upper end of the left plate body  14  is interposed therebetween, and have a corresponding rotating shaft coupling hole  31  corresponding to the rotating shaft coupling hole  19 , and thus the left plate body  14  is rotatably coupled by the rotating shaft  35  fastened while the rotating shaft coupling hole  19  and the corresponding rotating shaft coupling hole  31  coincide with each other. That is, the left arm  10  and the right arm  20  are coupled so as to be rotated around the rotating shaft  35 . 
     According to the present invention, since the left and right plate bodies  14  and  24  forming the left and right arms  10  and  20 , and the front and back side connecting plates  30   a  and  30   b  are manufactured in a manner in which the plate material formed of a metallic material is cut through the laser processing, the pressing processing or the like and then assembled, it is not necessary to manufacture a mold, and thus the manufacturing cost may be reduced, and also it may be easily manufactured. Also, since the construction elements are manufactured by the metallic material, a supporting force required in the handgrip having the high intensity may be provided. Furthermore, the left and right plate bodies  14  and  24  may be easily coupled with the left and right grips  12  and  22  formed of the metal rod. 
     Therefore, according to the present invention, the left and right arms  10  and  20  may be prevented from being damaged by the resilient force provided by the spring members  50   a  and  50   b  while accomplishing ease of manufacture. 
     According to the present invention, the stop member  40  is disposed on an upper surface of the right plate body  24 . The stop member  40  is disposed between the front and back side connecting plates  30   a  and  30   b , and coupled so as to be rotated around a hinge shaft  38 . To this end, hinge holes  37  and  42  in which the hinge shaft  38  is inserted are formed at the front and back side connecting plates  30   a  and  30   b  and the stop member  40 . 
     A control piece  44  is formed to protrude from a right end of the stop member  40 . The control piece  44  is used when the stop member  40  is pushed and then rotated to a right side around the hinge shaft  38 . 
     The stop member  40  is disposed so that a left end contact surface  41  is in contact with the contact part  17  of the left plate body  14 . The stop member  40  controls a spacing degree of the left arm  10  with respect to the right arm  20 . That is, when a user applies a strain to his/her hand such that the left and right arms  10  and  20  approach each other, and then releases the strain, the left and right arms  10  and  20  are rotated around the rotating shaft  35  by the resilient force in a spacing direction. When the left and right arms  10  and  20  are spaced a predetermined range or more, the contact part  17  of the left arm  10  is in contact with the left end contact surface  41  of the stop member  40 , and thus an additional rotation of the left arm  10  respect to the right arm  20  is restricted. The left and right arms  10  and  20  may be rotated with respect to each other to only a position in which the contact part  17  of the left arm  10  is in contact with the left end contact surface  41  of the stop member  40 . The position (referring to  FIG. 7 ) in which the left end contact surface  41  of the stop member  40  is disposed to be in contact with the contact part  17  of the left arm  10  is a restriction position of the stop member  40 . 
     Meanwhile, the stop member  40  may push the control piece  44  and may rotate the stop member  40  to a right side around the hinge shaft  38  (referring to  FIG. 11 ). In this case, since the left end contact surface  41  of the stop member  40  strays from its original position, and thus does not restrict a movement of the left arm  10  within the predetermined range, the left arm  10  and the right arm  20  may be allowed to be spaced to a position in which the resilient force is not applied by the spring members  50   a  and  50   b . A position of the stop member  40  at this time is a control position of the stop member  40 . When the stop member  40  is disposed at the control position, the spring members  50   a  and  50   b  is in a no-load state, and thus an intensity of the resilient force can be controlled by moving the position of the spring members  50   a  and  50   b  (this will be described again in detail with reference to  FIG. 12 ). When a control of the resilient force is completed, the stop member  40  is returned to its original position, while the left and right arms  10  and  20  approach each other. 
     According to the present invention, one pair of spring members  50   a  and  50   b  which are installed at the front and back sides of the upper portions of the left and right arms  10  and  20  to be symmetric to each other and connected with each other are installed. 
     Each of the spring members  50   a  and  50   b  includes a compression spring  59 , and left and right spring support portions  51   a  and  51   b  which are disposed at both ends of the compression spring  59  so that the compression spring  59  is interposed therebetween so as to be compressibly supported. 
     Each of the left and right spring support portions  51   a  and  51   b  includes a contact support portion  52  which an end of the compression spring  59  is in contact with and also supported by, and a guide  53  which extends toward an inside of each compression spring  59 . The guide  53  has a guide groove  54  which is formed in a lengthwise direction and in which a guide rod  55  is slidably inserted. Therefore, the compression spring  59  may be guided between the left and right spring support portions  51   a  and  51   b  to be compressed and released in the lengthwise direction. In the illustrated embodiment, the guide rod  55  is separately formed, and both ends of the guide rod  55  are inserted into the guide grooves  54  disposed at both sides. However, the guide rod  55  may be integrally formed with one guide  53 . Alternatively, the guide  53  may be formed so that the guide rod  55  is connected to one spring supporting part, and the guide groove  54  is provided at the other spring supporting part. 
     According to the present invention, the front and back side spring members  50   a  and  50   b  are connected with each other and integrally operated. To this end, through-holes  56   a  and  56   b  are formed at the left and right spring support portions  51   a  and  51   b  of each of the front and back side spring members  50   a  and  50   b , respectively. 
     In the front and back side spring members  50   a  and  50   b , the left spring support portions  51   a  are connected with each other by the left spring member coupling shaft  57 , and the right spring support portions  51   b  are connected with each other by a right spring member coupling shaft  58 . 
     First, in coupling of the left spring support portions  51   a , while the left spring support portions  51   a  are disposed at the front and back sides of the left plate body  14  of the left arm  10 , respectively, and the coupling shaft through-hole  18  of the left plate body  14  coincides with the through-holes  56   a  of the left spring support portions  51   a , the left spring member coupling shaft  57  is inserted and fixed therein. Therefore, the front and back side spring members  50   a  and  50   b  are coupled so as to be integrally rotated around the left spring member coupling shaft  57 . 
     The right spring support portions  51   b  on the front and back sides are also coupled to each other by the right spring member coupling shaft  58  inserted through the through-hole  56   b . The right spring support portions  51   b  on the front and back sides are also coupled, while the right plate body  24  is interposed therebetween. However, a middle portion of the right spring member coupling shaft  58  is disposed at the resilient force control groove  27 , and thus the right spring support portions  51   b  may be movable so as to control the resilient force. 
     A character (not shown) may be installed at the front and back side connecting plates  30   a  and  30   b  so as to indicate the intensity of the resilient force according to positions of the resilient force control grooves  27 , and a protrusion may be installed at portions of the front and back side connecting plates  30   a  and  30   b  and the left surface corresponding to the positions of the resilient force control grooves  27 . 
       FIG. 8  is a partial cross-sectional view illustrating a handgrip according to another embodiment of the present invention, in which a structure related to the stop member is modified, compared with the handgrip according to one embodiment of the present invention. In  FIG. 8 , the same components as those of the one embodiment of the present invention are designated by the same reference numerals. 
     Referring to  FIG. 8 , the handgrip according to the present invention further includes an elastic pressing part which is formed at an upper surface of the right plate body  24  so as to press a lower surface of the stop member  40  and thus to restrict a free rotation of the stop member  40 . A plurality of catching grooves  45  are formed at the lower surface of the stop member  40 . 
     The elastic pressing part serves to restrict the free rotation of the stop member  40 , and includes a spring installing groove  29  formed at the upper surface of the right plate body  24 , a spring  29   a  and a locking ball  29   b.    
     The spring installing groove  29  is formed at a position corresponding to a position of a hinge shaft  38  of the stop member  40 . The spring  29   a  elastically supports the locking ball  29   b  in the spring installing groove  29 , and provides a force which presses the locking ball  29   b  upward, and thus the stop member  40  may be prevented from being freely rotated at the restriction position. According to the present invention, the locking ball  29   b  is formed in a bead shape, and the plurality of catching grooves  45  in which the locking ball  29   b  is partly inserted and coupled are formed at the lower surface of the stop member  40 . 
     Both side edges of an upper end of the spring installing groove  29  are formed to be cupped slightly inward and thus to prevent separation of the bead-shaped locking ball  29   b . Front and back sides of the spring installing groove  29  are closed by the front and back side connecting plates  30   a  and  30   b . Since the locking ball  29   b  has the bead shape, the locking ball  29   b  is rotated and moved between the catching grooves  45 , when the stop member  40  is operated. Therefore, an operation of the stop member  40  may be performed smoothly. 
     As described above, the stop member  40  controls the spacing degree of the left arm  10  with respect to the right arm  20  at the restriction position, and serves to push the control piece  44  and thus to rotate the stop member  40  to the right side around the hinge shaft  38 , when the user wants to move the positions of the spring members  50   a  and  50   b , and thus to control the intensity of the resilient force. 
     However, since there is not a means for maintaining the stop member  40  at the restriction position, the stop member  40  may be deviated from the restriction position according to a motion of the user, regardless of the user&#39;s intention, when the handgrip is used. That is, when the user uses the handgrip while stretching his/her hand downward, an upper portion of the handgrip may be directed to the ground, and the stop member  40  may be freely rotated to the control position by its own weight. 
     However, as illustrated in  FIG. 8 , when the elastic pressing part is provided at the upper surface of the right plate body  24  so as to restrict the free rotation of the stop member at the restriction position, the locking ball  29   b  pressed upward by the spring  29   a  presses the lower surface of the stop member  40 , and thus the stop member  40  is maintained at the restriction position. Therefore, the stop member  40  may be prevented from being rotated without a pushing operation of the control piece  44 . 
     When the catching grooves  45  are formed at the lower surface of the stop member  40 , the locking ball  29   b  is coupled to the catching grooves  45  so as to support the stop member  40 , and thus the stop member  40  may be further stably supported. 
     A plurality of contact grooves  17   a  and  17   b  may be formed at the contact part  17  of the left arm  10  so as to correspond to a position of the left end contact surface  41  of the stop member  40  according to a coupling position between the locking ball  29   b  and the catching grooves  45 . The left end contact surface  41  of the stop member  40  may be in contact with one of the contact grooves  17   a  and  17   b  according to the coupling position between the locking ball  29   b  and the catching grooves  45 , and thus may control the spacing degree of the left arm  10  with respect to the right arm  20 . At this time, the spacing degree of the left arm  10  with respect to the right arm  20  may be changed according to positions of the left end contact surface  41  and the contact grooves. 
       FIGS. 9 and 10  are views illustrating a handgrip according to still another embodiment of the present invention, in which the left and right arms are modified. In  FIGS. 9 and 10 , the same components as those of the one embodiment of the present invention are designated by the same reference numerals. 
     Referring to  FIGS. 9 and 10 , the handgrip according to the present invention further includes left and right extending grips  11  and  21 . The left and right extending grips  11  and  21  are coupled to the left and right grips  12  and  22  so as to increase a length of each of the left and right grips  12  and  22 . 
     A coupling hole h is formed at a lower end surface of each of the grips  12  and  22 . The coupling hole h is formed to correspond to shapes of coupling members  12   a.    
     Like the grips  12  and  22 , the extending grips  11  and  21  are formed of a cylindrical metal rod, and includes an insertion supporting part  11   a  formed at an upper end of each thereof to be inserted into the coupling hole h, and an insertion hole  11   b  in which the coupling member  12   a  is inserted so as to pass therethrough. 
     In the handgrip illustrated in  FIGS. 9 and 10 , when the user does not use the extending grips  11  and  21 , the coupling member  12   a  is fastened into the coupling hole h of each of the grips  12  and  22 . 
     However, when the user wants to increase the length of each of the grips  12  and  22 , the coupling member  12   a  is separated, and the insertion supporting part  11   a  of each of the extending grips  11  and  21  is inserted into the coupling hole h so that the extending grips  11  and  21  coincide with the grips  12  and  22 , and the coupling member  12   a  is inserted and fixed into the coupling hole h of each of the grips  12  and  22  through the insertion hole  11   b . Therefore, the grips  12  and  22  are increased by the length of the extending grips  11  and  21 , respectively. 
     In the handgrip, a force required when the left and right arms  10  and  20  approach each other depends on the spring members  50   a  and  50   b  as well as a grasping position when the user grasps the grips  12  and  22 . As the user grasps the grips  12  and  22  at a position distant from the spring members  50   a  and  50   b , the required force is relatively reduced. 
     The handgrip according to the present invention is configured so as to control the intensity of the resilient force. Nevertheless, there is a limitation in a level of the intensity of the resilient force. Even though the handgrip is adjusted to have the smallest intensity of the resilient force, when grasping power of the user does not reach the adjusted resilient force, the user may couple the extending grips  11  and  21  so as to increase the length of each of the grips  12  and  22 , and may use the handgrip while grasping the grips  12  and  22  at a position which is more distant from the spring members  50   a  and  50   b.    
     Also, the left and right extending grips  11  and  21  allow the user to adjust and use the handgrip according to his/her hand size. In the handgrip, the lengths of the grips  12  and  22  of the left and right arms are manufactured according to an average hand size of normal persons. However, a person may have a relatively large hand size. In the case of the person having the relatively large hand size, the lengths of the grips  12  and  22  of the handgrip adjusted to the average hand size are short, and thus it is inconvenient to use the handgrip. 
     However, according to the still another embodiment of the present invention, since the user may extend the lengths of the grips  12  and  22  using the extending grips  11  and  21 , the person having the larger hand size than the average hand size may use the handgrip without any inconvenience. 
     Hereinafter, a process of adjusting the resilient force of the handgrip of the present invention will be described with reference to the handgrip illustrated in  FIGS. 7, 11 and 12  according to the one embodiment of the present invention. 
       FIG. 11  is a cross-sectional view of the handgrip according to one embodiment of the present invention, which illustrates a state in which the stop member  40  is rotated around the hinge shaft  38 . Compared with  FIG. 7 , it may be understood that the stop member  40  is moved from the restriction position of  FIG. 7  to the control position of  FIG. 11 . 
     As illustrated in  FIG. 11 , in order to adjust the intensity of the resilient force, first, the control piece  44  of the stop member  40  is pushed, and then the stop member  40  is rotated to the right side around the hinge shaft  38 . When the control piece  44  of the stop member  40  is pushed in a state in which the left and right arms  10  and  20  slightly approach each other and the left end contact surface  41  of the stop member  40  is spaced from the contact part  17 , the stop member  40  is easily rotated. 
     While the stop member is in the control position, the left end contact surface  41  of the stop member  40  is deviated from a position which is in contact with the contact part  17  of the left plate body  14 , and thus the left arm  10  may be rotated with respect to the right arm  20  to a position in which the resilient force is not applied. Since the right spring member coupling shaft  58  is deviated from the resilient force control grooves  27  in the no-load state in which the resilient force of the spring members  50   a  and  50   b  is not applied, the spring members  50   a  and  50   b  may be rotated around the left spring member coupling shaft  57 . In this state, the right spring member coupling shaft  58  is moved to one of the resilient force control grooves  27  desired by the user, and the left and right arms  10  and  20  approach each other, and the stop member  40  is returned to its original position, and thus the controlling of the resilient force is completed. 
       FIG. 12  is a cross-sectional view of the handgrip, which illustrates movable positions of the spring members  50   a  and  50   b . As illustrated in  FIG. 12 , the handgrip of the present invention may control the intensity of the resilient force according to the number of the resilient force control grooves  27 . When the right spring member coupling shaft  58  is disposed at the resilient force control grooves  27   a ,  27   b ,  27   c ,  27   d ,  27   e  and  27   f , resilient force operating lines L 1 , L 2 , L 3 , L 4 , L 5  and L 6  by the spring members  50   a  and  50   b  are formed. As positions of the resilient force operating lines L 1 , L 2 , L 3 , L 4 , L 5  and L 6  are changed, distances between the resilient force operating lines L 1 , L 2 , L 3 , L 4 , L 5  and L 6  and the rotating shaft  35  are changed, and thus the intensity of the resilient force is also changed. In the embodiment illustrated in  FIG. 12 , the intensity of the resilient force may be controlled in 6 stages. However, the stages may be increased or reduced depending on the embodiments. 
     Since the handgrip having the above-described structure has the spring members  50   a  and  50   b  at the front and back sides thereof, respectively, the intensity of the resilient force may be considerably increased, compared with the case in which one spring member is disposed between the left and right arms  10  and  20 . Also, since the spring members  50   a  and  50   b  are disposed at outsides of the left and right arms  10  and  20 , instead of insides thereof, a size of each of the spring members  50   a  and  50   b  may be increased without any interference. The resilient force provided by the compression spring  59  depends on a thickness, a wound diameter and a length of a spring wire forming the compression spring  59 . Since the spring members  50   a  and  50   b  are disposed at the outsides and thus have no interference with other elements, the thickness, the wound diameter and the length of the spring wire may be adjusted according to a design thereof. 
     Also, in the handgrip having the above-described structure, since the plate members manufactured in the cutting manner of the plate material formed of a metallic material through the laser processing or the press processing are used as main elements, it is possible to easily manufacture them, and the grip formed of the metal rod is also may be easily manufactured. Therefore, the handgrip may be easily manufactured at a low cost, compared with the method using the mold formed of a metallic material. Also, since each element of the handgrip may be formed of the metallic material, a sufficient supporting force may be ensured, even when the strength of the spring members  50   a  and  50   b  is increased. 
     Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.