Patent Publication Number: US-2012027511-A1

Title: Fastening device and object having the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority of Taiwanese Application No. 099124902, filed on Jul. 28, 2010. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a fastening device and an object having the same, and more particularly to a non-threaded fastening device and an object having the same, the fastening device being convenient to assemble and disassemble quickly. 
     2. Description of the Related Art 
     Referring to  FIGS. 1 and 2 , a fastening device  1  disclosed in Taiwanese Patent No. M288756 (Application No. 094216081) is used to interconnect a first housing  21  and a second housing  22 . The fastening device  1  includes two retaining hooks  11  disposed on the first housing  21  and spaced apart from each other in a left-to-right direction, and two retaining members  12  disposed on the second housing  22  and spaced apart from each other in the left-to-right direction. Each of the retaining hooks  11  has an arm  111  connected to the first housing  21 , and a hook portion  112  disposed on a bottom end of the arm  111 . The hook portions  111  extend respectively from the arms  111  in opposite directions. Each of the retaining members  12  has a retaining groove  121  engageable with the hook portion  112  of the corresponding retaining hook  11 . 
     When it is desired to fasten the first housing  21  to the second housing  22 , the retaining hooks  11  are pressed respectively toward the retaining members  12 . When downwardly facing inclined surfaces  113  of the hook portions  112  come into contact with upwardly facing inclined surfaces  122  of the retaining members  12 , the hook portions  112  and, thus, the arms  111  are pushed outwardly to thereby deform the arms  111 . As soon as the hook portions  112  are aligned respectively with the retaining grooves  121 , the former are biased into the latter due to the returning force of the deformed arms  111 . Hence, the hook portions  112  abut respectively against stop walls  123  to thereby prevent removal of the first housing  21  from the second housing  22 . 
     Since the arms  111  of the retaining hooks  11  are connected fixedly to the first housing  21 , if a force is applied improperly to either of the retaining hooks  11  during assembly or disassembly of the fastening device  1 , breakage may occur at the junction between the first housing  21  and the corresponding arm  111 . Therefore, it is desirable to assemble and disassemble the fastening device quickly, in such a manner to prevent breakage of the fastening device. 
     SUMMARY OF THE INVENTION 
     An object of this invention is to provide a fastening device that is convenient to interconnect two articles quickly and that can be prevented from breakage during operation. 
     Another object of this invention is to provide an object that includes a fastening device, which is convenient to interconnect two articles quickly and which can be prevented from breakage during operation. 
     According to an aspect of this invention, there is provided a fastening device adapted to fasten a first article to a second article, the second article being disposed on and above the first article, the fastening device comprising: 
     a first hook adapted to be disposed on the first article and having a first hook portion disposed at a top end thereof; 
     a stopper member adapted to be disposed on the first article and spaced apart from the first hook in a left-to-right direction, the stopper member having a stop surface facing the first hook portion; 
     two fixed plates adapted to be disposed on the second article and spaced apart from each other in a front-to-rear direction, each of the fixed plates having a pivot groove, and a first positioning portion spaced apart from and disposed under the pivot groove; and 
     a second hook connected pivotally between the fixed plates and extending between the first hook portion and the stop surface of the stopper member, the second hook having a second hook portion disposed at a bottom end thereof and engaging removably the first hook portion, two pivot shafts disposed respectively at two opposite sides thereof, and two second positioning portions disposed respectively at the two opposite sides thereof, one of the first and second hook portions having a first guiding inclined surface that faces upwardly, and a second guiding inclined surface that faces downwardly, the other of the first and second hook portions being contactable with one of the first and second guiding inclined surfaces, the pivot shafts being disposed respectively and rotatably within the pivot grooves, each of the second positioning portions being spaced apart from a corresponding one of the pivot shafts and engaging a corresponding one of the first positioning portions. 
     According to another aspect of this invention, there is provided an object comprising: 
     a first article; 
     a second article disposed on and above said first article; and 
     a fastening device including
         a first hook disposed on the first article and having a first hook portion disposed at a top end thereof,   a stopper member disposed on the first article and spaced apart from the first hook in a left-to-right direction, the stopper member having a stop surface facing the first hook portion,   two fixed plates disposed on the second article and spaced apart from each other in a front-to-rear direction, each of the fixed plates having a pivot groove, and a first positioning portion spaced apart from and disposed under the pivot groove, and   a second hook connected pivotally between the fixed plates and extending between the first hook portion and the stop surface of the stopper member, the second hook having a second hook portion disposed at a bottom end thereof and engaging removably the first hook portion, two pivot shafts disposed respectively at two opposite sides thereof, and two second positioning portions disposed respectively at the two opposite sides thereof, one of the first and second hook portions having a first guiding inclined surface that faces upwardly, and a second guiding inclined surface that faces downwardly, the other of the first and second hook portions being contactable with one of the first and second guiding inclined surfaces, the pivot shafts being disposed respectively and rotatably within the pivot grooves, each of the second positioning portions being spaced apart from a corresponding one of the pivot shafts and engaging a corresponding one of the first positioning portions.       

     As such, the second article can be quickly assembled to and disassembled from the first article, thereby resulting in convenience during use of the object. Furthermore, when an excessive force is applied to separate the second article from the first article, the second positioning portions are removed respectively from the first positioning portions to allow for rotation of the second hook about the pivot shafts to thereby prevent breakage of the second hook. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of this invention will become apparent in the following detailed description of a preferred embodiment of this invention, with reference to the accompanying drawings, in which: 
         FIG. 1  is an exploded perspective view of a conventional fastening device disclosed in Taiwanese Patent No. M288756; 
         FIG. 2  is an assembled perspective view of the conventional fastening device; 
         FIG. 3  is a partly exploded perspective view of the preferred embodiment of an object according to this invention; 
         FIG. 4  is a fragmentary, partly exploded perspective view of the preferred embodiment, illustrating that a second hook is removed from two fixed plates; 
         FIG. 5  is a fragmentary, partly exploded perspective view of the preferred embodiment, illustrating modifications to first and second positioning portions; 
         FIG. 6  is a fragmentary schematic view of the preferred embodiment, illustrating that a first hook portion is pushed outwardly by a second hook portion during assembly of first and second articles; 
         FIG. 7  is a fragmentary schematic side view of the preferred embodiment, illustrating that the second hook portion is confined between the first hook portion and a stopper member; 
         FIG. 8  is a fragmentary perspective view of the preferred embodiment, illustrating that the second hook portion is confined between the first hook portion and the stopper member; 
         FIG. 9  is a fragmentary schematic side view of the preferred embodiment, illustrating that the first hook portion is pushed outwardly by the second hook portion during separation of the first and second articles; 
         FIG. 10  is a fragmentary schematic side view of the preferred embodiment, illustrating that movement of the second hook portion in a first or second direction results in separation of the first and second positioning portions and clockwise rotation of the second hook; and 
         FIG. 11  is a fragmentary schematic side view of the preferred embodiment, illustrating that movement of the second hook portion in a third direction results in separation of the first and second positioning portions and counterclockwise rotation of the second hook. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Before the present invention is described in greater detail in connection with the preferred embodiments, it should be noted that similar elements and structures are designated by like reference numerals throughout the entire disclosure. 
     Referring to  FIG. 3 , the preferred embodiment of an object  300  according to this invention includes a first article  3 , a second article  4 , and a fastening device  5  for fastening the first and second articles  3 ,  4  to each other. In this embodiment, the object  300  is exemplified using a mainframe housing of a notebook computer. The first article  3  is an upper housing portion. The second article  4  is a lower housing portion. Alternatively, the object  300  may be a housing of a planet computer, a personal digital assistant, or a mobile phone, or any other similar product having two articles that are interconnected removably. 
     With further reference to  FIG. 4 , the fastening device  5  includes a first hook  51 , a stopper member  52 , two fixed plates  53 , and a second hook  54 . The first hook  51  is disposed on the first article  3 , and has a first hook portion  512 . The stopper member  52  is disposed on the first article  3 , is spaced apart from the first hook  51  in a left-to-right direction, and has a stop surface  520  facing the first hook portion  512 . The fixed plates  53  are disposed on the second article  4 , and are spaced apart from each other in a front-to-rear direction. Each of the fixed plates  53  has a pivot groove  531 , and a first positioning portion  532  disposed under the pivot groove  531 . The second hook  54  is connected pivotally between the fixed plates  53 , and extends between the first hook portion  512  and the stopper member  52 . The second hook  54  has a second hook portion  542  disposed at a bottom end thereof and engaging removably the first hook portion  512 , two pivot shafts  543  disposed respectively at two opposite sides thereof, and two second positioning portions  544  disposed respectively at the two opposite sides thereof. The first hook portion  512  has a first guiding inclined surface  513  that faces upwardly, and a second guiding inclined surface  514  (see  FIG. 6 ) that faces downwardly. The second hook portion  542  is movable to contact the first or second guiding inclined surface  513 ,  514 . The pivot shafts  543  are disposed respectively and rotatably within the pivot grooves  531 . Each of the second positioning portions  544  is spaced apart from and disposed under the corresponding pivot shaft  543 , and engages the corresponding first positioning portion  532 . As such, the second article  4  can be assembled to and disassembled from the first article  3  conveniently and quickly. 
     The detailed structures of the components as well as assembly and disassembly thereof will be described. The first hook  51  further has an arm portion  511  connected integrally to the first article  3 . The first hook portion  512  is disposed at a top end of the arm portion  511 . The second hook  54  further has an arm portion  541 . The second hook portion  542  is disposed at a bottom end of the arm portion  541 . The stopper member  52  further has a stop block  521  connected integrally to the first article  3 . The stop block  521  has the stop surface  520 . The distance between the stop block  521  and the first hook portion  512  is slightly greater than the width of the arm portion  541  of the second hook  54  so as to allow for extension of the arm portion  541  of the second hook  54  between the stop block  521  and the first hook portion  512 . The distance between the stop block  521  and the first hook portion  512  is smaller than the width of the second hook portion  542  so as to confine the second hook portion  542  between the first hook  51  and the stop block  521 . 
     In this embodiment, the first hook  51  is made of a plastic material such that, when the first hook portion  512  is pushed by the second hook portion  542  of the second hook  54 , that arm portion  511  of the first hook  51  deforms to have a returning force. The stopper member  52  is also connected integrally to the first article  3 , as described above, so that the stop block  521  is deformed easily. To diminish the deformation of the stop block  521 , the stopper member  52  further has an upright reinforcing plate  522  connected between the first article  3  and an outer side surface  520 ′ of the stop block  521  opposite to the stop surface  520 . 
     Each of the fixed plates  53  is connected integrally to the second article  4 . The pivot shafts  543  extend respectively from front and rear sides of the arm portion  541 . Since the pivot shafts  543  are disposed respectively and rotatably within the pivot grooves  531 , as described above, the second hook  54  is rotatable about the pivot shafts  543  between the fixed plates  53 . In this embodiment, each of the pivot grooves  531  has a curved engaging groove portion  533  that receives rotatably the corresponding pivot shaft  543 , and a guiding groove portion  534  that is open in the left-to-right direction and that guides movement of the corresponding pivot shaft  543  into the engaging groove portion  533 . As such, the second hook  54  can be assembled quickly to the fixed plates  53 . 
     In this embodiment, each of the first positioning portions  532  is a circular groove, and each of the second positioning portions  544  is a cylindrical tongue engaging removably the corresponding circular groove. Since the first positioning portions  532  engage respectively the second positioning portions  544 , the arm portion  541  of the second hook  54  is held at a vertical position, and rotation of the second hook  54  about the pivot shafts  543  is prevented. In an alternative arrangement shown in  FIG. 5 , each of the first positioning portions  532  is a cylindrical tongue, and each of the second positioning portions  544  is a circular groove. 
     Referring to  FIGS. 6 ,  7 , and  8 , when it is desired to fasten the second article  4  to the first article  3 , the second article  4  is moved relative to the first article  3  to align the second hook  54  with the space between the first hook  51  and the stop block  521  of the stopper member  52 . Subsequently, the second article  4  is moved toward the first article  3 , so that a first contact inclined surface  545  of the second hook portion  542  comes into contact with the first guiding inclined surface  513 . Hence, a horizontal force component is applied to the first guiding inclined surface  513  to push the first hook portion  512  outwardly to thereby deform the arm portion  511  of the first hook  51 . As soon as the second hook portion  542  moves downwardly past the first hook portion  512 , the second article  4  comes into contact with the first article  3  to thereby prevent further downward movement of the second hook portion  542  relative to the first hook portion  512 , and the first hook portion  512  is biased to its original position due to the returning force of the arm portion  511 . Hence, the second guiding inclined surface  514  of the first hook portion  512  abuts against a second contact inclined surface  546  of the second hook portion  542 , as shown in  FIG. 7 . At this time, the fastening device  5  is in a locking state, and the second article  4  is fastened to the first article  3 . 
     Preferably, the stopper member  52  further has a third guiding inclined surface  523  that faces upwardly and that is aligned with the first guiding inclined surface  513 . The second hook portion  542  further has a contact curve surface  547  contactable with the third guiding inclined surface  523 . During downward movement of the second hook  54 , when the contact curve surface  547  comes into contact with the third guiding inclined surface  523 , since the rigidity of the stop block  521  of the stopper member  52  is increased by the reinforcing plate  522 , the stop block  521  cannot deform. As a consequence, the second hook portion  542  is guided by the third guiding inclined surface  523  to contact the first guiding inclined surface  513  of the first hook portion  512 , so as to facilitate movement of the second hook portion  542  to a position under the first hook portion  512 , thereby allowing for easy assembly of the fastening device  5 . 
     Referring to  FIGS. 7 and 9 , during disassembly of the second article  4  from the first article  3 , when the second article  4  is pulled upwardly in a first direction (I) or upwardly and rightwardly in a second direction (II), the second contact inclined surface  546  of the second hook portion  542  comes into contact with the second guiding inclined surface  514  of the first hook portion  512 . At this time, a force component is applied to the second guiding inclined surface  514  by the second hook portion  542  to push the first hook portion  512  outwardly to thereby deform the arm portion  511 . Upon contact of the second hook portion  542  with the first hook portion  512 , a reaction force occurs so that a clockwise torque (T) is applied to the second hook portion  542 . If the torque (T) is smaller than a torque value so that the first positioning portions  532  cannot be removed from the second positioning portions  544 , the arm portion  541  of the second hook  54  will remain in the vertical position. Also during disassembly of the second article  4  from the first article  3 , the second article  4  may be pulled upwardly and leftwardly in a third direction (III). When the arm portion  541  of the second hook  54  comes into contact with the stop block  521  of the stopper member  52 , a reaction force occurs so that a lateral force (F) is applied to the arm portion  541 . If the lateral force (F) is smaller than a force value so that the first positioning portions  532  cannot be removed from the second positioning portions  544 , the arm portion  541  of the second hook  54  will remain in the vertical position. It should be noted that, the torque value and the force value are determined according to the sizes of the first and second positioning portions  532 ,  544 . 
     When the second hook portion  542  moves upwardly past the first hook portion  512 , the fastening device  5  is in a release state, and the second article  4  can be separated from the first article  3 . 
     Referring to  FIG. 10 , when the second article  4  is moved in the first or second directions (I, II), if the clockwise torque (T) is greater than the torque value so that the first positioning portions  532  are separated from the second positioning portions  544 , the second hook  54  will rotate clockwise about the pivot shafts  543  relative to the fixed plates  53 . As such, breakage of the arm portion  541  of the second hook  54  resulting from excessive clockwise torque can be prevented. Since the second hook  54  further has a first stop inclined surface  548  disposed at a top end thereof and extending downwardly and leftwardly, as soon as the first stop inclined surface  548  rotates to contact a bottom surface of the second article  4 , further clockwise rotation of the second hook  54  is prevented, thereby limiting the clockwise rotational angle of the second hook  54 . 
     Referring to  FIG. 11 , when the second article  4  is moved in the third directions (III), if the lateral force (F) is greater than the force value so that the first positioning portions  532  is separated from the second positioning portions  544 , the second hook  54  will rotate counterclockwise about the pivot shafts  543  relative to the fixed plates  53 . As such, breakage of the arm portion  541  of the second hook  54  resulting from excessive lateral force can be prevented. Since the second hook  54  further has a second stop inclined surface  549  disposed at the top end thereof and extending downwardly and rightwardly, as soon as the second stop inclined surface  549  rotates to contact the bottom surface of the second article  4 , further counterclockwise rotation of the second hook  54  is prevented, thereby limiting the counterclockwise rotational angle of the second hook  54 . 
     In view of the above, due to the design of the fastening device  5 , the second article  4  can be quickly assembled to and disassembled from the first article  3 , thereby resulting in convenience during use of the object  300 . Furthermore, since the pivot shafts  543  of the second hook  54  are disposed respectively and rotatably within the engaging groove portions  533  in the fixed plates  53 , and since the second positioning portions  544  of the second hook  54  engage respectively and removably the first positioning portions  532  of the fixed plates  53 , when the second hook  54  is subjected to an excessive torque or force, the second positioning portions  544  are separated respectively from the first positioning portions  532  to allow for rotation of the second hook  54  about the pivot shafts  543 , thereby preventing the breakage of the second hook  54 . Thus, the object of this invention is achieved. 
     With this invention thus explained, it is apparent that numerous modifications and variations can be made without departing from the scope and spirit of this invention. It is therefore intended that this invention be limited only as indicated by the appended claims.