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CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2013-0133758 filed in the Korean Intellectual Property Office on Nov. 5, 2013, the entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to a knob structure of a glove box for a vehicle, and more particularly, to a knob structure of a glove box for a vehicle which has two types of knobs including a pull-type knob and a push-type knob on a glove box so as to improve convenience for a user. 
     BACKGROUND ART 
     Recently, as the supply of vehicles rapidly grows and comfort of vehicles is rapidly developed, various devices for convenience, which may provide convenience and comfort to occupants, are considered important as much as technical issues of vehicles such as traveling stability or ride quality. 
     As one of the devices for convenience provided in the vehicle, a glove box, which accommodates and stores items which a driver needs, is installed at an instrument panel positioned in front of a front passenger seat. 
     As a knob of the glove box for a vehicle, there currently are a push-type knob and a pull-type knob. 
     The two types of knobs of the glove box have advantages and disadvantages in terms of convenience for the user, respectively. The push-type knob has an advantage in that it is convenient for a male driver seated on the driver seat to operate the push-type knob while maintaining a direction in which the push-type knob is moved, but has a disadvantage in that an old or weak person or a female driver, who has a relatively short arm, needs to forcibly and deeply push the push-type knob in order to open the glove box. The pull-type knob has a problem in that the driver needs to inconveniently pull the pull-type knob while bending the hand on the basis of the front passenger seat. 
     LITERATURE OF RELATED ART 
     Korean Patent No. 10-0568723 
     SUMMARY OF THE INVENTION 
     The present invention has been made in an effort to provide a knob structure of a glove box for a vehicle which has two types of knobs including a pull-type knob and a push-type knob on a glove box so as to improve convenience for a user. 
     An exemplary embodiment of the present invention provides a knob structure of a glove box for a vehicle including: a push-type knob unit which is coupled to a glove box by a first fixed hinge, and operated by being pushed; a pull-type knob unit which is coupled to the glove box by a second fixed hinge, and operated by being pulled; and a rod unit which is connected to the push-type knob unit and the pull-type knob unit, and converts rotational motion by an operation of the push-type knob unit or the pull-type knob unit into rectilinear motion so as to open and close the glove box. 
     The push-type knob unit may have a first catching member which protrudes inward from one region of the push-type knob unit, the pull-type knob unit may have a second catching member which protrudes inward from one end of the pull-type knob unit, the rod unit may have a first supporting member and a second supporting member which are provided to protrude vertically from a rod that opens and closes the glove box by rectilinear motion, the first catching member may be connected with the first supporting member, and the second catching member may be connected with the second supporting member, such that the rotational motion by the operation of the push-type knob unit or the pull-type knob unit is converted into the rectilinear motion so as to open and close the glove box. 
     The push-type knob unit may have a projection that protrudes inward, and the knob structure may further include a first supporting hinge which is provided in the glove box, and comes into contact with the projection when the push-type knob unit is rotated, so as to control the rotation of the push-type knob unit. 
     The knob structure may further include a second supporting hinge which is provided between the first catching member and the second catching member, and comes into contact with the second catching member when the pull-type knob unit is rotated, so as to control the rotation of the pull-type knob. 
     The second catching member may have a ‘           ’ shape, and the push-type knob unit may be moved inside a ‘         ’-shaped internal space by the ‘         ’ shape when the push-type knob unit is operated, such that the push-type knob unit and the pull-type knob unit are separately operated.
     The push-type knob unit and the pull-type knob unit may be positioned on the same plane, and surfaces where the push-type knob unit is in contact with the pull-type knob unit may be chamfered or rounded in order to prevent the push-type knob unit and the pull-type knob unit from interfering with each other when the push-type knob unit and the pull-type knob unit are operated. 
     When the first catching member may be connected with the first supporting member, and the second catching member may be connected with the second supporting member, elastic materials may be attached to contact surfaces so as to prevent abrasion or noise. 
     According to the dual structure of the glove box for a vehicle of the present invention, both the pull-type knob and the push-type knob are provided on the glove box, thereby improving convenience for a user. 
     The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of a knob structure of a glove box for a vehicle according to an exemplary embodiment of the present invention. 
         FIG. 2  is a rear perspective view of the knob structure of the glove box for a vehicle of  FIG. 1 . 
         FIG. 3  is an exploded perspective view of a knob of the glove box for a vehicle of  FIG. 1 . 
         FIG. 4  is a top plan view illustrating a stationary state of the knob of the glove box for a vehicle of  FIG. 1 . 
         FIG. 5  is a front perspective view when a push-type knob of  FIG. 1  is operated. 
         FIG. 6  is a rear perspective view when the push-type knob of  FIG. 1  is operated. 
         FIG. 7  is a front perspective view when a pull-type knob of  FIG. 1  is operated. 
         FIG. 8  is a rear perspective view when the pull-type knob of  FIG. 1  is operated. 
     
    
    
     It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. 
     In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. 
     DETAILED DESCRIPTION 
     Hereinafter, a knob structure of a glove box for a vehicle according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, in denoting reference numerals to constituent elements of respective drawings, it should be noted that the same elements will be designated by the same reference numerals although they are shown in different drawings. Hereinafter, an exemplary embodiment of the present invention will be described, but, of course, the technical spirit of the present invention is not restricted or limited thereto, but the exemplary embodiment of the present invention may be modified by a person with ordinary skill in the art to be variously performed. 
       FIG. 1  is a front perspective view of a knob structure of a glove box for a vehicle according to an exemplary embodiment of the present invention,  FIG. 2  is a rear perspective view of the knob structure of the glove box for a vehicle according to the exemplary embodiment of the present invention, and  FIG. 3  is an exploded perspective view of a knob of the glove box for a vehicle according to the exemplary embodiment of the present invention. 
     Referring to  FIGS. 1 to 3 , a knob structure of a glove box for a vehicle according to an exemplary embodiment of the present invention includes a push-type knob unit  10 , a pull-type knob unit  20 , and a rod unit  30 . 
     The push-type knob unit  10  includes a push-type knob cover  11 , a first catching member  16  which protrudes from an inner surface of the push-type knob cover  11  in an approximately vertical direction, and first fixed hinges  14  which protrude at one end of the push-type knob cover  11  in upward and downward directions. The push-type knob cover  11  has a rectangular recessed portion  11   a , and the first fixed hinges  14  are provided at an end of the recessed portion  11   a . Since the first fixed hinges  14  need to be positioned inward from a front surface of the push-type knob cover  11 , the first fixed hinges  14  may be positioned on upper and lower portions of a protruding portion  18  that protrudes inward from the end of the recessed portion  11   a.    
     The pull-type knob unit  20  includes a pull-type knob cover  21  which has a recessed portion coupling space  21   a  to which the recessed portion  11   a  formed on the push-type knob cover  11  of the push-type knob unit  10  is coupled, a ‘           ’-shaped second catching member  24  which protrudes inward from one end of the pull-type knob cover  21 , and second fixed hinges  22  which protrude on a connection portion between the pull-type knob cover  21  and the second catching member  24  in the upward and downward directions.
     The rod unit  30  includes a rod  31  which opens and closes the glove box, and a first transmission member  34  and a second transmission member  32  which protrude from the rod  31  in a direction toward the knob of the glove box. 
     The pull-type knob cover  21  and the push-type knob cover  11  are coupled to each other, and positioned on the same plane. The aforementioned coupling shape of the pull-type knob cover  21  and the push-type knob cover  11  is merely an exemplary embodiment, and the coupling shape may be variously modified and used. 
     The push-type knob unit  10  and the pull-type knob unit  20  are separately coupled to the glove box (not illustrated), and the push-type knob unit  10  is moved in a ‘           ’-shaped internal space of the second catching member  24  when the push-type knob unit  10  is operated, such that the push-type knob unit  10  and the pull-type knob unit  20  are separately operated.
     Since the push-type knob cover  11  and the pull-type knob cover  21  need not interfere with each other when the push-type knob cover  11  and the pull-type knob cover  21  are operated, surfaces where the push-type knob cover  11  comes into contact with the pull-type knob cover  21  are chamfered or rounded so that the push-type knob cover  11  and the pull-type knob cover  21  do not interfere with each other. 
       FIG. 4  is a top plan view of the knob structure of the glove box for a vehicle according to the exemplary embodiment of the present invention when the knob is not operated. 
     Referring to  FIG. 4 , the first catching member  16  of the push-type knob unit  10  is in contact with the first transmission member  34  of the rod unit  30 , and the second catching member  24  of the pull-type knob unit  20  is in contact with the second transmission member  32  of the rod unit  30 . 
     A projection  17 , which protrudes from the inner surface of the push-type knob cover  11 , is formed on the push-type knob cover  11 , and a first supporting hinge  40 , which limits a radius of rotation in a predetermined range when the push-type knob cover  11  is rotated, and a second supporting hinge  42 , which is positioned in the internal space of the glove box between the first catching member  16  and the second catching member  24 , and limits a radius of rotation in a predetermined range when the pull-type knob cover  21  is rotated, are formed in an internal space of the glove box. 
     The first and second catching members  16  and  24 , and the first and second transmission members  34  and  32  are injection molded bodies, such that there is a risk that abrasion and noise may occur when these components are operated while being in contact with each other. Therefore, elastic materials may be coupled to contact surfaces so as to prevent the occurrence of abrasion and noise. In an exemplary embodiment, silicone, rubber or the like may be used as the elastic material. 
       FIG. 5  is a front perspective view when the push-type knob of the knob structure of the glove box for a vehicle according to the exemplary embodiment of the present invention is operated.  FIG. 6  is a rear perspective view when the push-type knob of the knob structure of the glove box for a vehicle according to the exemplary embodiment of the present invention is operated. 
     Referring to  FIGS. 5 and 6 , when the push-type knob cover  11  is pushed inward when the push-type knob is operated, the first catching member  16  is rotated in a clockwise direction about a rotation axis a-a formed by coupling the first fixed hinges  14  and the glove box (not illustrated), and the first transmission member  34  of the rod unit  30 , which is in contact with the first catching member  16 , is rectilinearly moved such that the rod  31  opens the glove box. In this case, when the push-type knob cover  11  is rotated, the projection  17  formed on the push-type knob cover  11  comes into contact with the first supporting hinge  40  so as to adjust the rotation. 
       FIG. 7  is a front perspective view when the pull-type knob of the knob structure of the glove box for a vehicle according to the exemplary embodiment of the present invention is operated, and  FIG. 8  is a rear perspective view when the pull-type knob of the knob structure of the glove box for a vehicle according to the exemplary embodiment of the present invention is operated. 
     Referring to  FIGS. 7 and 8 , when the pull-type knob cover  21  is pulled outward when the pull-type knob is operated, the second catching member  24  is rotated in a clockwise direction about a rotation axis b-b formed by coupling the second fixed hinge  22  and the glove box (not illustrated), and the second transmission member  32  of the rod unit  30 , which is in contact with the second catching member  24 , is rectilinearly moved such that the rod  31  opens the glove box (not illustrated). In this case, when the second catching member  24  is rotated, the second catching member  24  comes into contact with the second supporting hinge  42  so as to adjust the rotation. 
     As described above, according to the knob structure of the glove box for a vehicle of the present invention, both the pull-type knob and the push-type knob are provided on the glove box, such that the knob structure may be applied to vehicles being developed while maintaining the existing operation mechanism, thereby improving convenience for a user. 
     As described above, the exemplary embodiments have been described and illustrated in the drawings and the specification. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.

Summary:
A knob structure of a glove box for a vehicle according to an exemplary embodiment of the present invention includes: a push-type knob unit which is coupled to a glove box by a first fixed hinge, and operated by being pushed; a pull-type knob unit which is coupled to the glove box by a second fixed hinge, and operated by being pulled; and a rod unit which is connected to the push-type knob unit and the pull-type knob unit, and converts rotational motion by an operation of the push-type knob unit or the pull-type knob unit into rectilinear motion so as to open and close the glove box.