Abstract:
A plug-in module ( 100 ) includes a pair of opposite sidewalls ( 11, 21 ) parallel to each other and a latch mechanism ( 8 ). The latch mechanism includes a pair of sliders ( 4 ), a bail ( 3 ) and a pair of ejectors ( 5 ). The sliders are sliderably attached to the sidewalls and are configured and arranged to linerear move relative to the sidewalls. The bail is attached to the sidewalls and one ends of the sliders and is configured and arranged such that the rotate motion of the bail results in the linerear movement of the sliders. The ejectors are pivotally attached to the sidewalls and cooperate with the sliders. The ejectors are configured and arranged such that the rotation of the bail results in the linerear movement of the sliders to actuate the ejectors to outwardly rotate relative to the sidewalls adapted for deflecting the latch tab of the module receptacle to separate the plug-in module from the module receptacle.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention generally relates to a plug-in module, and more particularly to a plug-in module used for high-speed transmission. 
   2. Description of Related Art 
   SFP (Small Form-factor Pluggable), X-SFP and QSFP are all modules for fiber optic transmission or signal transmission. All of the modules are of small size or form factor which is important. The smaller the form factor of the module, the less space taken on a printed circuit board to which it couples. A smaller form factor allows a greater number of modules to be coupled onto a printed circuit board to support additional communication channels. However, the smaller form factor makes it more difficult for a user to handle. 
   When such a module embedded in a system fails, it is desirable to replace it, particularly when other communication channels are supported by other modules. To replace a failed module, it needs to be pluggable into a module receptacle. While, plugging in a new module is usually easy, it is more difficult to remove the failed module because of other components surrounding it. Additionally, a user should not attempt to pull on cables of the module in order to try and remove a failed module or else the user might cause damage thereto. 
   A typical release method for a pluggable module is to push in on the module itself and then pull out on the module to release it from a cage assembly or module receptacle. It has been determined than this method is not very reliable with users complaining of the difficulty in removing pluggable modules in such manner. Users often complain that traditional methods offer little leverage in getting a sufficient grip on the module when attempting to pull it out of a module receptacle. Another complaint is that traditional actuators used to remove modules are inaccessible or invisible. Other users complain than once released by the traditional method, it is difficult to withdraw the module out of its cage or module receptacle. 
   Therefore, designers developed different solutions to solve above problems accounted by the users, such as disclosed by U.S. Pat. Nos. 6,851,867, 6,749,448, 6,884,097, 6,908,323, 7,052,306, 6,824,416 and 7090523. The theories of theses patents are substantially the same, that is each module is received in corresponding cage or module receptacle and comprises a pair of sliders with forward ends engaging with tabs of the cage, and a bail or lever capable of rotating to actuate the sliders linearly to separate forward ends of the sliders from the tabs. The action theory of theses patents successfully solve the problems mentioned above. The present invention provides a plug-in module with an improved latch mechanism operating in a theory different from that of these patents while still successfully solving the problems. 
   BRIEF SUMMARY OF THE INVENTION 
   Accordingly, an object of the present invention is to provide a plug-in module with improved latch mechanism for unplugging the plug-in module conveniently. 
   In order to achieve the above-mentioned object, a plug-in module configured for latching engagement with a module receptacle adapted for mounting to a printed circuit board comprises a pair of opposite sidewalls parallel to each other and a latch mechanism. The latch mechanism comprises a pair of sliders, a bail and a pair of ejectors. The sliders are sliderably attached to the sidewalls and are configured and arranged to linerear move relative to the sidewalls. The bail is attached to the sidewalls and one ends of the sliders and is configured and arranged such that the rotate motion of the bail results in the linerear movement of the sliders. The ejectors are pivotally attached to the sidewalls and cooperate with the sliders. The ejectors are configured and arranged such that the rotation of the bail results in the linerear movement of the sliders to actuate the ejectors to outwardly rotate relative to the sidewalls adapted for deflecting the latch tab of the module receptacle to separate the plug-in module from the module receptacle. 
   Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIGS. 1-3  are exploded, perspective views of a plug-in module in accordance with the present invention and viewed from different aspects; 
       FIGS. 4-5  are partially assembled views of  FIGS. 2-3 ; 
       FIGS. 6-7  are assembled views of the plug-in module of  FIGS. 1 and 3 ; and 
       FIGS. 8-12  are cross-section views of the plug-in module taken along lines  8 - 8  to  12 - 12  of  FIG. 6 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Reference will now be made to the drawing figures to describe the present invention in detail. 
   Referring to  FIGS. 1-3 , a plug-in module  100  in accordance with the present invention comprises a base  2 , a cover  1  assembled with the base  2  to form a die case housing  7 , and a latch mechanism  8  assembled to the base  2  and the cover  1  for unplugging the plug-in module  100  from a module receptacle (not shown) conveniently. The latch mechanism  8  comprises a pair of die-cast sliders  4  assembled to the base  2  and the cover  1 , a pair of die-cast ejectors  5  assembled to the base  2  and the cover  1  and capable of being actuated by the sliders  4 , a bail  3  stamped from metal sheet and assembled to the cover  1  and the sliders  4  capable of rotating to actuate the sliders  4  linearly move, and a pair of bias elements  6  assembled to the base  2  and the sliders  4  for providing elastic restoring force to the sliders  4 . In the preferred embodiment, the plug-in module  100  is a QSFP (Quad Small Form-factor Pluggable) module in accordance with Revision 1.0 of the QSFP Transceiver specification released on Dec. 1, 2006. However, the plug-in module  100  also can be other types of modules without betray the spirit of the present invention. 
   The cover  1  comprises a step-shape main upper wall  10 , a pair of first sidewalls  11  extending downwardly from opposite side edges of the upper wall  10 , opposite first front and rear walls  11 ,  12  with different heights downwardly extending from front and rear edges of the upper wall  10  and connecting with the pair of first sidewalls  11 . The upper wall  10  extends forwardly beyond the first front wall  13  to form a first front flange  14  with a pair of elliptical holes  140  laterally arranged. An L-shape cutout  141  recesses downwardly from upper surface of the upper wall  10  and locates at a left corner of the upper wall  10 . A flange  101  is formed on the upper wall  10  to divide the cover  1  into a front first mating section  102  and a rear first installation section  103  which is higher and shorter than the first mating section  102  but lower than the flange  101 . The flange  101  indicates the final insertion position of the plug-in module  100 . 
   The opposite first sidewalls  11  are partially cut inwardly to form a pair of first accommodating spaces  110  which extend from a position adjacent to the first rear wall  12  till a middle position of the first mating section  102  corresponding to contours of the sliders  4 . The rear section of the first accommodating space  110  before the flange  101  is formed by completely cutting through the first sidewall  11  along up-to-down direction. The front section of the first accommodating space  110  at and after the flange  101  is formed by partially cut the first sidewall  11  along up-to-down direction with upper flange of the first sidewall  11  left and a first sliding slit  112  recessed in the upper flange. A first cooperating recess  113  is recessed inwardly from forward end of the first accommodating space  110  and opens toward outside. A circular first pivot hole  114  recesses upwardly from the first sidewall  11  and communicating with the first cooperating recess  113 . The first cooperating recess  113  is of L-shape and communicates with the first pivot hole  114 , the first accommodating space  110  and the first sliding slit  112 . The first cooperating recess  113  forms an inner first step  1130  and an L-shape outer second step  1132  respectively corresponding to the contours of the sliders  4  and the actuators  5 . A pair of rods  104  extend outwardly from outer periphery of the upper wall  10  and locate adjacent to the first rear wall  12 . Each rod  104  extends into corresponding first accommodating space  110  for cooperating with the bail  3 . 
   The first rear wall  12  has a relatively large thickness along mating direction and defines a first semicircular exit opening  120  for the exist of a cable (not shown). A plurality of teeth  121  are formed on inner periphery of the first exit opening  120  for interferentially engaging with the cable. A pair of first fastening holes  122  are defined at opposite sides of the exit opening  120 . Another pair of first fastening holes  122  are formed in a pair of standoffs formed adjacent to the first pivot holes  114  all for fastening to the base  2 . A pair of tips  130  are formed at two corners of the first front wall  13  and below the first front wall  13  to form a pair of spaces  131  between the bottom surfaces of the first sidewalls  11 . A continuous slot  15  recesses upwardly from inner edges of the first sidewalls  11  and the first rear wall  12 . 
   The base  2  comprises a step-shape bottom wall  20 , a pair of second sidewalls  21  extending upwardly from opposite side edges of the bottom wall  20 , opposite second front and rear walls  22 ,  23  upwardly extending from front and rear edges of the bottom wall  20  and connecting with the pair of second sidewalls  21 . 
   The bottom wall  20  comprises a front second mating section  202  and a rear second installation section  203  lower than the second mating section  202  to form a second flange  201  therebetween for indicating the final insertion position of the plug-in module  100  together with the first flange  101 . The second rear wall  22  has a relatively large thickness along the mating direction and partially cut to form a semicircular second exit opening  220  which cooperates with the first exit opening  120  to form an exit channel  70  ( FIG. 7 ) for the exist of the cable (no shown). The second rear wall  22  also defines a pair of circular second fastening holes  222  at opposite sides of the second exit opening  220  corresponding to the first fastening holes  122  for a pair of screws  9  protruding therethrough to fasten the base  2  with the cover  1 . The bottom wall  20  extends beyond the second front wall  23  to form a second front flange  24  parallel spaced from the first front flange  14  with a front end of a printed circuit board (not shown), which is accommodated between the base  2  and the cover  1 , exposed between the front flanges  14 ,  24 . 
   Each second sidewall  21  has different thicknesses along the mating direction of the plug-in module  100 . The middle and rear sections of the sidewall  21  are thicker than front section of the sidewall  21  and form the thicker section of the sidewall  21  and the front section is a thinner section of the sidewall  21 . The thicker section is partially cut to form a second accommodating space  210  which opens toward outside corresponding to the first accommodating space  110  of the cover  1  to corporately form an accommodating channel  71  of the plug-in module  100  to receive the sliders  4 . A protruding block  215  protrudes outwardly from middle section of the inner part of the sidewall  21  to divide the second accommodating space  210  into a rear wider receiving section, a middle second sliding slit  212  corresponding to the first sliding slit  112  and a front second cooperating recess  213  corresponding to the first cooperating recess  113 . A second pivot hole  214  is defined in a front end of the thicker section of the second sidewall  21  corresponding to the first pivot hole  114  and communicates with the second cooperating recess  213 . Corresponding to the first and second steps  1130 ,  1132 , the second cooperating recess  230  forms an inner first step  2130  on inner part of the second sidewall  21  and an outer second step  2132  on outer part of the second sidewall  21 . A continuous rib  25  forms on inner periphery of the pair of second sidewalls  21  and the second rear wall  22  for being received in the continuous slot  15 . A pair of tips  231  extends forwardly from forward ends of the pair of second sidewalls  21  and locates above the second front wall  23 . A deeper bias receiving slot  2160  ( FIG. 12 ) recesses downwardly from the second accommodating space  210  before the protruding block  215  with a pair of restriction ribs  216  formed at opposite sides of the bias receiving slot  2160  to restrict the movement of the bias element  6 . Particularly, the restriction rib  216  adjacent to the second rear wall  22  is divided into two parts by an aligning slit (not shown) for cooperating with the slider  4 . 
   The pair of sliders  4  are arranged face-to-face to be assembled to the base  2  and the cover  1 . Each slider  4  comprises a rear mounting portion  41 , a middle main body  42  and a front leading end  43 . The mounting portion  41  is partially cut to define a cutout  410  on interior surface thereof and forms a pin  412  in the cutout  410 . A lower supporter  413  is formed below the cutout  410  and part of the main body  42  with a foot portion  414  downwardly extending therefrom and adjacent to a rear end of the slider  4 . The main body  42  is a rectangular body with two pairs of guiding portions  420  formed on upper and lower edges thereof adjacent to interior surface thereof. One pair of guiding portions  420  aligning with each other along vertical direction is in a middle position of the main body  42  and the other pair locates adjacent to the leading end  43 . The leading end  43  forms an actuating surface  430  on outer surface thereof and a step-shape latch  431  on inner surface thereof. 
   The pair of ejectors  5  are assembled to the base  2  and the cover  1  to be actuated by the sliders  4  for releasing the plug-in module  100  from the module receptacle. Each ejector  5  comprises a front pivot  51  vertically arranged for being received in the first and second pivot holes  114 ,  214 , and a main portion  52  extending rearwardly from the pivot  51  with an inclined surface  53  formed at distal end of the main portion  52 . The main portion  52  comprises an inner surface and an opposite outer surface. A first block rib  520  is formed on the inner surface of the main portion  52  and adjacent to the pivot  51  and a pair of wedge-shape cutouts  523  is defined at upper and lower sections of the main portion  52  to form a bridge  521  and a pair of bottom second block ribs  522 . 
   The bail  3  is of U-shape and comprises a transverse handle portion  30  formed with a curved grasp section  300  thereon, and a pair of drive arms  31  extending downwardly from opposite sides of the handle portion  30  for cooperating with the cover  1  and actuating the sliders  4  to forwardly move and cause the ejectors  5  outwardly move to separate the plug-in module  100  from the module receptacle. Each drive arm  31  defines a circular hole  310  in an upper section thereof and a U-shape railway  312  communicating with bottom edge thereof. 
   In assembly, referring to  FIGS. 4-5  in conjunction with  FIGS. 1-3 , the bail  3 , the sliders  4  and the ejectors  5  are firstly assembled to the cover  1 . The bail  3  is firstly assembled to the cover  1  with the pair of rods  104  of the cover  1  inserting into the circular holes  310  of the drive arms  31  and the railways  312  extend into the first accommodating spaces  110 . Then, the sliders  4  are assembled to the cover  1  along down-to-up direction. The upper portions of the sliders  4  occupy the first accommodating spaces  110  with outer surfaces of the sliders  4  substantially coplanar with the outer surfaces of the first sidewalls  11 . The pair of pins  412  of the mounting portions  41  of the sliders  4  protrude into the railways  312  and the upper pair of guiding portions  420  are received into the first sliding slit  112  and capable sliding along the first sliding slit  112 . The upper sections of the leading ends  43  are received in the first cooperating recess  113  with the latches  431  latching with the first step  1130 . The ejectors  5  are assembled to the cover  1  with the pivots  51  inserted into the first pivot holes  114  and the main portion  52  occupying the left spaces of the first cooperating recesses  113 . In such circumstances, the actuating surfaces  430  of the sliders  4  attach to the inclined surfaces  53  of the ejectors  5  in the first cooperating recess  113  without clearance. The L-shape second step  1132  abuts against the bridge  521  and the second block rib  522 . 
   Referring to  FIGS. 6-7  in conjunction with  FIGS. 1-3  and  8 - 12 , the pair of bias elements  6  are firstly assembled to the base  2  and received in the bias receiving slots  2160  with opposite ends elastically abutting against the pair of restriction ribs  216 . The base  2  is then assembled to the cover  1 , the sliders  4  and the ejectors  5  together with the pair of bias elements  6  with the pair of tips  231  inserted into the spaces  131  of the cover  1  then rotating the base  2  a certain angle to combine the base  2  and the cover  1  into the housing  7 . The lower sections of the sliders  4  and the ejectors  5  occupy the second accommodating space  210 , the second cooperating recess  213  and the second pivot hole  214  in a manner similar to the assembly described above. The foot portion  414  of the mounting portion  51  is received in the slit (not shown) to abut against one end of the bias element  6  for compressing the bias element  6  and the pair of guiding portions  420  are received in the second sliding slit  212  and capable of sliding along the second sliding slit  212 . The remaining portions of the leading end  423  and the main portion  52  of the ejector  5  are corporately received in the second cooperating recess  213  and the remaining portion of the pivot  51  is received in the second pivot hole  214 . 
   After the above assembly, the plug module  100  is achieved. The first and second accommodating spaces  110 ,  210  corporately form the accommodating channel  71  of the housing  7  to receive the sliders  4 , and the first and second cooperating recesses  113 ,  213  corporately form a cooperating space  72  of the housing  7  which is commonly used by the sliders  4  and the ejectors  5 . The bail  3  is located in a vertical first position when the plug-in module  100  mates with the module receptacle. When removing the plug-in module  100  from the module receptacle, operator may grasp the handle portion  30  of the bail  3  and exerts a rearward force to the bail  3  till to a second position. The bail  3  rotates around the rods  104  along counter-clockwise direction, while the pins  412  received in the railways  312  together with the sliders  4  move forwardly with the guiding portions  420  sliding along the first and second sliding slits  112 ,  212  and the foot portions  414  compressing the bias elements  6 . Thus, the actuating surface  430  slides along the inclined surface  53  of the ejector  5  to actuate the main portion  52  of the ejector  5  outwardly move with the pivots  51  rotating in the first and second pivot holes  114 ,  214 . The outwardly moving main portions  52  push tabs of the module receptacle then escape from the latch condition with the tabs, operator may pull the bail  3  rearwardly to pull the plug-in module  100  from the module receptacle. When release the pulling force to the bail  3 , the compressed bias elements  6  resume to their original statement, thus, providing elastic restore force to the sliders  4  and the ejectors  5 . 
   It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.