Patent Publication Number: US-2011051976-A1

Title: Headphone

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority of Taiwanese application no. 098215672, filed on Aug. 25, 2009. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a headphone. 
     2. Description of the Related Art 
     A conventional headphone, such as that disclosed in Taiwanese Utility Model Publication No. M326307, includes a headband, first and second pivot joints, and first and second ear cups. The headband includes left and right frames, and an intermediate frame. Each of the first and second pivot joints includes a seat and a post. The seat of the first pivot joint is coupled rotatably to an end of the intermediate frame of the headband and is formed with a groove. The post of the first pivot joint is formed on an end of the left frame of the headband, extends into the groove in the seat of the first pivot joint, and is coupled rotatably to the seat of the first pivot joint with the use of a screw, thereby permitting rotation of the left frame of the headband relative to the seat of the first pivot joint. The seat of the second pivot joint is coupled rotatably to another end of the intermediate frame of the headband and is formed with a groove. The post of the second pivot joint is formed on an end of the right frame of the headband, extends into the groove in the seat of the second pivot joint, and is coupled rotatably to the seat of the second pivot joint with the use of a screw, thereby permitting rotation of the right frame of the headband relative to the seat of the second pivot joint. Each of the first and second ear cups is coupled to a respective one of the left and right frames of the headband. 
     The aforementioned conventional headphone is disadvantageous in that the seat and the post of each of the first and second pivot joints are made from plastic and therefore wear easily. 
     SUMMARY OF THE INVENTION 
     Therefore, the object of the present invention is to provide a headphone that can overcome the aforesaid drawback of the prior art. 
     According to the present invention, a headphone comprises a headband, a pivot joint, and an ear cup. The pivot joint includes a first rod that is coupled rotatably to the headband and that defines a first axis, a second rod that defines a second axis, and an intermediate rod that interconnects the first and second rods. The pivot joint is rotatable relative to the headband about the first axis. The ear cup is coupled rotatably to the second rod of the pivot joint, and is rotatable relative to the pivot joint about the second axis. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which: 
         FIG. 1  is a perspective view of the preferred embodiment of a headphone according to this invention; 
         FIG. 2  is an exploded perspective view illustrating a left frame of a headband, a first pivot joint, and a first ear cup of the preferred embodiment; 
         FIG. 3  is an exploded perspective view illustrating a right frame of the headband, a second pivot joint, and a second ear cup of the preferred embodiment; 
         FIG. 4  is a partial sectional view illustrating left frame of the headband, the first pivot joint, and the first ear cup of the preferred embodiment in an assembled state; 
         FIG. 5  is a perspective view illustrating a transmission wire unit and the first/second pivot joint of the preferred embodiment in an assembled state; 
         FIG. 6  is a sectional view of the preferred embodiment in an assembled state; 
         FIG. 7  is a schematic view illustrating a shell of the first/second ear cups of the preferred embodiment; 
         FIGS. 8 and 9  are sectional views illustrating assembling of the first/second pivot joint on the first/second ear cup of the preferred embodiment; 
         FIGS. 10 and 11  are schematic view illustrating assembling of the first/second pivot joint on the first/second ear cup of the preferred embodiment; 
         FIG. 12  is a perspective view illustrating a first rod of the first/second pivot joint of the preferred embodiment; 
         FIG. 13  is a perspective view illustrating an abutting piece of the first/second ear cup of the preferred embodiment; 
         FIG. 14  is a perspective view of a modified first/second pivot joint of the preferred embodiment; 
         FIG. 15  is an exploded perspective view of the modified first/second pivot joint of the preferred embodiment in  FIG. 14 ; 
         FIG. 16  is a perspective view of another modified first/second pivot joint of the preferred embodiment; 
         FIGS. 17 and 18  are sectional views illustrating the first and second ear cups when rotated relative to the first and second pivot joints of the preferred embodiment, respectively; 
         FIG. 19  is a schematic view of the preferred embodiment illustrating the first and second ear cups when rotated to a rear side of the headband; and 
         FIG. 20  is a partial sectional view of the preferred embodiment taken on line  20 -- 20  of  FIG. 19 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , the preferred embodiment of a headphone  100  according to this invention is shown to include a headband  1 , first and second pivot joints  2 , and first and second ear cups  3 . 
     The headphone  100  converts electric signals into sounds. 
     The first and second ear cups  3  are held in place over the user&#39;s ears by the headband  1 . 
     The headband  1  is generally C-shaped, and includes left and right frames  12 , and an intermediate frame  11  that interconnects the left and right frames  12  thereof. As illustrated in  FIGS. 2 ,  4 , and  6 , the left frame  12  of the headband  1  includes outer and inner shells  121 ,  122 . The inner shell  122  of the left frame  12  of the headband  1  is fastened on the outer shell  121  of the left frame  12  of the headband  1  with the use of a screw (not shown). The outer and inner shells  121 ,  122  of the left frame  12  of the headband  1  cooperatively define a receiving space  123  therebetween. The inner shell  122  of the left frame  12  of the headband  1  has front and read sides, and an inner side that interconnects the front and read sides thereof. The inner shell  122  of the left frame  12  of the headband  1  is formed with a guide hole  124  therethrough that is in spatial communication with the receiving space  123  in the left frame  12  of the headband  1  and that extends from the inner side to the rear side thereof. 
     As illustrated in  FIGS. 3 and 6 , the right frame  12  of the headband  1  includes outer and inner shells  121 ,  122 . The inner shell  122  of the right frame  12  of the headband  1  is fastened on the outer shell  121  of the right frame  12  of the headband  1  with the use of a screw (not shown). The outer and inner shells  121 ,  122  of the right frame  12  of the headband  1  cooperatively define a receiving space  123  therebetween. The inner shell  122  of the right frame  12  of the headband  1  has front and read sides, and an inner side that interconnects the front and read sides thereof. The inner shell  122  of the right frame  12  of the headband  1  is formed with a guide hole  124  therethrough that is in spatial communication with the receiving space  123  in the right frame  12  of the headband  1  and that extends from the inner side to the rear side thereof. 
     The headband  1  further includes left and right abutting pieces  13 . The left abutting piece  13  of the headband  1  is disposed in the receiving space  123  in the left frame  12  of the headband  1 , and has opposite ends that are fastened on the inner shell  122  of the left frame  12  of the headband  1  with the use of a pair of screws (not shown). The right abutting piece  13  of the headband  1  is disposed in the receiving space  123  in the right frame  12  of the headband  1 , and has opposite ends that are fastened on the inner shell  122  of the right frame  12  of the headband  1  with the use of a pair of screws (not shown). 
     The first pivot joint  2  includes first and second rods  22 ,  23 , and an intermediate rod  21  that interconnects the first and second rods  22 ,  23  thereof. The first and second rods  22 ,  23  and the intermediate rod  21  of the first pivot joint  2  are transverse to each other. The first rod  22  and the intermediate rod  21  of the first pivot joint  2  form a T-shape. Likewise, the second rod  23  and the intermediate rod  21  of the first pivot joint  2  form a T-shape. The first rod  22  of the first pivot joint  2  is disposed in the receiving space  123  in the left frame  12  of the headband  1 , abuts against the left abutting piece  13  of the headband  1 , and defines a first axis. The intermediate rod  21  of the first pivot joint  2  extends into the guide hole  124  in the inner shell  122  of the left frame  12  of the headband  1 . The construction as such permits rotation of the first pivot joint  2  relative to the headband  1  about the first axis. 
     In this embodiment, the left abutting piece  13  of the headband  1  has an arcuate surface  131 . The first rod  22  of the first pivot joint  2  abuts against the arcuate surface  131  of the left abutting piece  13  of the headband  1 . This facilitates smooth rotation of the first pivot joint  2  about the first axis and prevents the first pivot joint  2  from wobbling. 
     The first ear cup  3  includes a shell  31 , and a cover  32  mounted on the shell  31  thereof. The shell  31  and the cover  32  of the first ear cup  3  cooperatively define a receiving space  34  therebetween for receiving a left speaker (not shown) and electronic components (not shown). The first ear cup  3  further includes an abutting piece  33  disposed in the receiving space  34  therein and fastened on the shell  31  thereof with the use of screws (not shown). The shell  31  of the first ear cup  3  is formed with a guide hole  311  therethrough that is in spatial communication with the receiving space  34  in the first ear cup  3 . 
     The second rod  23  of the first pivot joint  2  is disposed in the receiving space  34  in the first ear cup  3 , abuts against the abutting piece  33  of the first ear cup  3 , and defines a second axis. The intermediate rod  21  of the first pivot joint  2  extends into the guide hole  311  in the shell  31  of the first ear cup  3 . The construction as such permits rotation of the first ear cup  3  relative to the first pivot joint  2  about the second axis. 
     In this embodiment, the abutting piece  33  of the first ear cup  3  has an arcuate surface  331 . The second rod  23  of the first pivot joint  2  abuts against the arcuate surface  331  of the abutting piece  33  of the first ear cup  3 . This facilitates smooth rotation of the first ear cup  3  about the second axis and prevents the first ear cup  3  from wobbling. 
     The second pivot joint  2  includes first and second rods  22 ,  23 , and an intermediate rod  21  that interconnects the first and second rods  22 ,  23  thereof. The first and second rods  22 ,  23  and the intermediate rod  21  of the second pivot joint  2  are transverse to each other. The first rod  22  and the intermediate rod  21  of the second pivot joint  2  form a T-shape. Likewise, the second rod  23  and the intermediate rod  21  of the second pivot joint  2  form a T-shape. The first rod  22  of the second pivot joint  2  is disposed in the receiving space  123  in the right frame  12  of the headband  1 , abuts against the right abutting piece  13  of the headband  1 , and defines a third axis. The intermediate rod  21  of the second pivot joint  2  extends into the guide hole  124  in the inner shell  122  of the right frame  12  of the headband  1 . The construction as such permits rotation of the second pivot joint  2  relative to the headband  1  about the third axis. 
     In this embodiment, the right abutting piece  13  of the headband  1  has an arcuate surface  131 . The first rod  22  of the second pivot joint  2  abuts against the arcuate surface  131  of the right abutting piece  13  of the headband  1 . This facilitates smooth rotation of the second pivot joint  2  about the third axis and prevents the second pivot joint  2  from wobbling. 
     The second ear cup  3  includes a shell  31 , and a cover  32  mounted on the shell  31  thereof. The shell  31  and the cover  32  of the second ear cup  3  cooperatively define a receiving space  34  therebetween for receiving a right speaker (not shown) and electronic components (not shown). The second ear cup  3  further includes an abutting piece  33  disposed in the receiving space  34  therein and fastened on the shell  31  thereof with the use of screws (not shown). The shell  31  of the second ear cup  3  is formed with a guide hole  311  therethrough that is in spatial communication with the receiving space  34  in the second ear cup  3 . 
     The second rod  23  of the second pivot joint  2  is disposed in the receiving space  34  in the second ear cup  3 , abuts against the abutting piece  33  of the second ear cup  3 , and defines a fourth axis. The intermediate rod  21  of the second pivot joint  2  extends into the guide hole  311  in the shell  31  of the second ear cup  3 . The construction as such permits rotation of the second ear cup  3  relative to the second pivot joint  2  about the fourth axis. 
     In this embodiment, the abutting piece  33  of the second ear cup  3  has an arcuate surface  331 . The second rod  23  of the second pivot joint  2  abuts against the arcuate surface  331  of the abutting piece  33  of the second ear cup  3 . This facilitates smooth rotation of the second ear cup  3  about the fourth axis and prevents the second ear cup  3  from wobbling. 
     Each of the first and second ear cups  3  further includes an ear cup cushion  35  provided on the cover  32  thereof for making the headphone  100  more comfortable to use. 
     In this embodiment, the first and second pivot joints  2 , the left and right abutting pieces  13  of the headband  1 , and the abutting pieces  33  of the first and second ear cups  3  are made from metal. As such, wearing of the first and second pivot joints  2 , the left and right abutting pieces  13  of the headband  1 , and the abutting pieces  33  of the first and second ear cups  3  due to repetitive rotations of the first and second pivot joints  2  and the first and second ear cups  3  can be prevented. 
     It is noted that each of the first and second pivot joints  2  is hollow. That is, each of the first and second rods  22 ,  23  and the intermediate rod  21  of each of the first and second pivot joints  2  defines an axially extending channel  221 ,  231 ,  211 . 
     With further reference to  FIG. 5 , the headphone  100  further includes a transmission wire unit  4  that extends through the shell  31  of the first ear cup  3 , the channel  221 ,  231 ,  211  in each of the first and second rods  22 ,  23  and the intermediate rod  21  of the first pivot joint  2 , a through-hole  133  in the left abutting piece  13  of the headband  1 , a channel  111  in the intermediate frame  11  of the headband  1 , a through-hole  133  in the right abutting piece  13  of the headband  1 , and the channel  221 ,  231 ,  211  in each of the first and second rods  22 ,  23  and the intermediate rod  21  of the second pivot joint  2 . The transmission wire unit  4  has a first end connected to the right speaker in the second ear cup  3 . 
     The headphone  100  further includes a second transmission wire unit (not shown) that extends into the shell  31  of the first ear cup  3  and that has a first end connected to the speaker in the first ear cup  3 . 
     Each of the transmission wire unit  4  and the second transmission wire unit further has a second end connected to a signal source (not shown), such as a computer or a portable player, for transmission of signals from the signal source to the left and right speakers. 
     When it is desired to assemble the transmission wire unit  4  on the headphone  100 , the first end of the transmission wire unit  4  is first passed through the shell  31  of the first ear cup  3 , the channel  211  in the intermediate rod  21  of the first pivot joint  2 , the through-hole  133  in the left abutting piece  13  of the headband  1 , the channel  111  in the intermediate frame  11  of the headband  1 , the hole  133  in the right abutting piece  13  of the headband  1 , and the channel  211  in the intermediate rod  21  of the second pivot joint  2 . Then, the transmission wire unit  4  is squeezed into the channel  221  in the first rod  22  of the first pivot joint  2  through an opening  222  in the first rod  22  of the first pivot joint  2 , and the channel  231  in the second rod  23  of the first pivot joint  2  through an opening  232  in the second rod  23  of the first pivot joint  2 . Thereafter, the transmission wire unit  4  is squeezed into the channel  221  in the first rod  22  of the second pivot joint  2  through an opening  222  in the first rod  22  of the second pivot joint  2 , and the channel  231  in the second rod  23  of the second pivot joint  2  through an opening  232  in the second rod  23  of the second pivot joint  2 . 
     It is noted that since the transmission wire unit  4  extends through the channels  211  in the intermediate rods  21  of the first and second pivot joints  2 , the transmission wire unit  4  is not exposed at a junction of the left frame  12  of the headband  1  and the first ear cup  3  and a junction of the right frame  12  of the headband  1  and the second ear cup  3 , and is prevented from being tangled or pulled when the first or second ear cups  3  are rotated. Moreover, since the transmission wire unit  4  extends through the first and second rods  22 ,  23  of the first and second pivot joints  2 , bends in the transmission wire unit  4  is protected from being accidentally pressed, which may result in a short circuit or a signal transmission error. 
     In an alternative embodiment, the channels  221  in the first rods  22  of the first and second pivot joints  2  are dispensed with. In this case, the arcuate surface  131  of each of the left and right abutting pieces  13  of the headband  1  defines a channel for extension of the transmission wire unit  4  therethrough. 
     The first rod  22  of each of the first and second pivot joints  2  includes a first rod portion  224  formed on the intermediate rod  21  of a respective one of the first and second pivot joints  2 , and a second rod portion  225  fastened to the first rod portion  224  thereof. 
     The first rod portion  224  of the first rod  22  of the first pivot joint  2  defines the channel  221  and is formed with the opening  222 , and is further formed with an engaging groove  226 . In this embodiment, the first rod portion  224  of the first rod  22  of the first pivot joint  2  has a size less than that of the guide hole  311  in the shell  31  of the first ear cup  3 . The second rod portion  225  of the first rod  22  of the first pivot joint  2  extends into the engaging groove  226  in the first rod portion  224  of the first rod  22  of the first pivot joint  2 . The first and second rod portions  224 ,  225  of the first rod  22  of the first pivot joint  2  have a total size larger than that of the guide hole  311  in the shell  31  of the first ear cup  3 . 
     The first rod portion  224  of the first rod of the second pivot joint  2  defines the channel  221  and is formed with the opening  222 , and is further formed with an engaging groove  226 . In this embodiment, the first rod portion  224  of the first rod  22  of the second pivot joint  2  has a size less than that of the guide hole  311  in the shell  31  of the second ear cup  3 . The second rod portion  225  of the first rod  22  of the second pivot joint  2  extends into the engaging groove  226  in the first rod portion  224  of the first rod  22  of the second pivot joint  2 . The first and second rod portions  224  of the first rod  22  of the second pivot joint  2  has a total size larger than that of the guide hole  311  in the shell  31  of the second ear cup  3 . 
     When it is desired to assemble the first and second pivot joints  2  on the first and second ear cups  3 , respectively, as illustrated in  FIGS. 8 and 9 , the first rod portion  224  of the first rod  22  is first inserted through the guide hole  311  in the shell  31 . Then, as illustrated in  FIGS. 7 ,  10  and  11 , the second rod  23  is engaged to a pair of engaging grooves  312  in an inner surface of the shell  31 . Subsequently, as illustrated in  FIG. 12 , the second rod portion  225  of the first rod  22  is inserted into the engaging groove  226  in the first rod portion  224  of the first rod  22 . Thereafter, as illustrated in  FIG. 13 , the abutting piece  33  is fastened on the shell  31 , and the transmission wire unit  4  is inserted through a through-hole  341  in the shell  31 . 
     In this embodiment, the second rod portion  225  is fastened to the first rod portion  224  using an adhesive (not shown). 
     In an alternative embodiment, the second rod portion  225  is fastened to the first rod portion  224  using a rivet (not shown). 
     In yet another embodiment, as illustrated in  FIG. 14 , the second rod portion  225  is fastened to the first rod portion  224  using a screw  228 . In particular, as illustrated in  FIG. 15 , the engaging groove  226  in the first rod portion  224  is defined by a hole-defining wall formed with a thread  229 . The second rod portion  225  is formed with a through-hole  227 . The screw  228  extends through the through-hole  227  in the second rod portion  225  and engages threadedly the thread  229  on the hole-defining wall of the first rod portion  224 . 
     It is noted that, as illustrated in  FIG. 16 , the first rod  22  and the intermediate rod  21  may be formed in one piece. In this case, the length of the first rod  22  may be made shorter than that of the guide hole  311  in the shell  31  or the length of the guide hole  311  may be made longer than that of the first rod  22 . 
     When it is desired to assemble the first and second pivot joints  2  on the headband  1 , the first rod  22  is first inserted into the receiving space  123  in a respective one of the left and right frames  12  of the headband  1  through the guide hole  124  in the inner shell  122  of the respective one of the left and right frames  12  of the headband  1 . Then, each of the left and right abutting pieces  13  is fastened on the inner shell  122  of the respective one of the left and right frames  12 . Thereafter, the inner shell  122  of each of the left and right frames  12  of the headband  1  is fastened on the outer shell  122  of the respective one of the left and right frames  12  of the headband  1 . 
     As illustrated in  FIGS. 17 and 18 , when the headphone  100  is worn by the user, since the first and second pivot joints  2  are rotatable relative to the headband  1 , and since the first and second ear cups  3  are rotatable relative to the first and second pivot joints  2 , respectively, the first and second ear cups  3  align correctly with the ears of the users. 
     The arcuate surface  131  of each of the left and right abutting pieces  13  of the headband  1  is formed with a receiving groove  132  (see  FIGS. 2 and 3 ). 
     When the headphone  100  is not in use, as illustrated in  FIGS. 19 and 20 , the first and second ear cups  3  may be rotated to a rear side of the headband  1  such that the intermediate rods  21  of the first and second pivot joints  2  are received in the receiving grooves  132  in the arcuate surfaces  131  of the left and right abutting pieces  13  of the headband  1 , respectively, thereby minimizing space occupied by the headphone  100 . 
     It is noted that the intermediate rod  21  of each of the first and second pivot joints  2  is disposed at a position between opposite ends of the first rod  22  of a respective one of the first and second pivot joints  2 . As such, when each of the first and second pivot joints  2  are rotated relative to the headband  1  via a respective one of the first and second ear cups  3 , the force exerted on each of the first and second pivot joints can be uniformly transmitted to the arcuate surface  131  of a respective one of the left and right abutting pieces  13  of the headband  1 . This results in smoother and more stable rotations of the first and second pivot joints  2 . 
     In an alternative embodiment, the headphone  100  includes only the first pivot joint  2  and the first ear cup  3 . 
     While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.