Abstract:
An optical connector assembly includes: an optical connector having a connection portion at a top end thereof, the connection portion being connected to an optical module, the optical connector having a latch and a lever disposed on a side surface thereof, the latch securing connection between the optical connector and the optical module, the lever releasing the latch; a housing having a through-hole that incorporates the optical connector therein and an opening that is formed at a position at which part of the lever of the optical connector protrudes through the opening, the opening communicating with the through-hole; and a cover having the housing disposed therein, the cover having a plate-like protruding portion on an inner wall thereof, the protruding portion protruding toward the housing; wherein when the protruding portion is located at a position of the opening, the protruding portion presses the lever.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2010-214356 filed on Sep. 24, 2010, the entire contents of which are incorporated herein by reference. 
     FIELD 
     The embodiments disclosed herein are relates to a connector of an optical cable with a cover. 
     BACKGROUND 
     With the increase in transmission speed from wireless base station apparatuses to switching systems, an optical transmission method has been used for cell phones and wireless systems. Since, in general, a wireless base station apparatus is installed outdoors, a connector portion of an optical cable connected to the apparatus needs to be waterproof. In some cases, in order to change a connector portion into a dedicated waterproof connector, a conversion cable is employed. However, since such a conversion cable is costly, a technique for directly making a connection portion between an optical module of an apparatus and an optical connector connected to the optical module waterproof is described below. 
       FIGS. 1A to 1D  illustrate an example of an optical connector and an optical module widely used for optical transmission.  FIG. 1A  is a side view of the optical connector and the optical module.  FIG. 1B  is a top view of the optical connector and the optical module. As illustrated in  FIG. 1A , an optical connector  1  is provided at the top end of an optical cable  5  in order to connect the optical cable  5  to an optical module  50  of an apparatus. As a general-purpose optical connector, an LC optical connector having a specification defined by the IEC61754-20 standard is widely used. A latch  2  having a protruding portion  6  in the middle of the upper surface thereof and a trigger lever  3  used to release the latch  2  by pressing the latch  2  are provided in the middle of the LC optical connector  1 . The latch  2  and the trigger lever  3  are made of resin. The latch  2  and the trigger lever  3  are flexible. Even when the trigger lever  3  is being pressed and, thus, the latch  2  is also being pressed, the trigger lever  3  and the latch  2  return to their original shapes after the trigger lever  3  is released. 
     A jack  51  used for connecting the LC optical connector  1  is formed at the top end of the optical module  50 . As illustrated in  FIG. 1B , an opening  52  is formed in the top surface of the optical module  50 .  FIG. 1C  is a side view of the LC optical connector  1  connected to the optical module  50 .  FIG. 1D  is a top view of the LC optical connector  1  connected to the optical module  50 . When the LC optical connector  1  is plugged into the optical module  50 , the latch  2  is temporarily pressed towards the body of the LC optical connector  1  by a protruding portion  6  in the jack  51 . Subsequently, if the LC optical connector  1  is further plugged into the optical module  50 , the protruding portion  6  of the latch  2  reaches the position of the opening  52  formed in the upper surface of the optical module  50 . At that time, the pressure that is applied to the protruding portion  6  disappears. Accordingly, the latch  2  returns to its original shape. Therefore, the protruding portion  6  of the latch  2  protrudes through the opening  52 . At that time, since the protruding portion  6  of the latch  2  protrudes through the opening  52  and is caught on the edge of the opening  52 , the LC optical connector  1  may not be removed from the optical module  50 . In order to remove the LC optical connector  1  from the optical module  50 , the trigger lever  3  has to be pressed. By doing so, the latch  2  is pressed downward, and the protruding portion  6  caught by the opening  52  is released. 
       FIG. 2A  illustrates the LC optical connector  1  with a waterproof cover  30 . A portion of the LC optical connector  1  to which the optical cable  5  is attached is made waterproof by using a housing  10 . Furthermore, the housing  10  is made waterproof by using the waterproof cover  30 . Thus, the connecting portion of the optical connector  1  with the apparatus is made waterproof.  FIG. 2B  illustrates the LC optical connector  1  with a waterproof cover illustrated in  FIG. 2A  connected to the optical module  50  of the apparatus with a waterproof cover. 
     By fitting a waterproof cover  40  provided on the outer side of the apparatus so as to surround the optical module  50  with the waterproof cover  30  provided on the optical module side, the connection portion between the optical module  50  and the LC optical connector  1  is completely covered and, therefore, is made waterproof. However, after the LC optical connector  1  with the waterproof cover  30  has been connected to the apparatus, the optical cable may not be removed in order to maintain or repair a board of the apparatus. That is, since the latch  2  and the trigger lever  3  are completely covered by the waterproof cover  30 , the latch may not be released. Therefore, in the case where a waterproof cover is attached, a general-purpose LC connector needs to be configured so that a latch and a trigger lever are removable by scraping, or an LC connector without a latch needs to be prepared. 
     The followings are reference documents.
     [Document 1] Japanese Laid-open Patent Publication No. 04-208904.   

     SUMMARY 
     According to an aspect of the embodiment, an optical connector assembly includes: an optical connector having a connection portion at a top end thereof, the connection portion being connected to an optical module, the optical connector having a latch and a lever disposed on a side surface thereof, the latch securing connection between the optical connector and the optical module, the lever releasing the latch; a housing having a through-hole that incorporates the optical connector therein and an opening that is formed at a position at which part of the lever of the optical connector protrudes through the opening, the opening communicating with the through-hole; and a cover having the housing disposed therein, the cover having a plate-like protruding portion on an inner wall thereof, the protruding portion protruding toward the housing; wherein the cover is attached to the housing in a relatively movable manner, and wherein when the protruding portion is located at a position of the opening, the protruding portion presses the lever. 
     The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIGS. 1A to 1D  illustrate connection between an optical module and an optical connector; 
         FIGS. 2A and 2B  illustrate an existing optical connector with a waterproof cover; 
         FIGS. 3A and 3B  illustrate an optical connector with a waterproof cover according to an embodiment of the present disclosed technology; 
         FIG. 4  illustrates an optical connector with a waterproof cover before the optical connector is fitted to an optical module according to the embodiment; 
         FIG. 5  illustrates the optical connector connected to an optical module according to the embodiment; 
         FIG. 6  illustrates the optical connector with a waterproof cover and an optical module that are fitted to each other; 
         FIGS. 7A and 7B  illustrate an optical module of an apparatus and a waterproof cover of the apparatus; 
         FIGS. 8A to 8C  illustrate the mechanism of the optical connector according to the embodiment; 
         FIGS. 9A to 9C  illustrate the steps of manufacturing an optical connector according to the embodiment; 
         FIGS. 10A to 10C  illustrate the steps of manufacturing an optical connector according to the embodiment; and 
         FIGS. 11A to 11C  illustrate the steps of manufacturing an optical connector according to the embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments of the present disclosed technology are described in detail below with reference to the accompanying drawings.  FIGS. 3A and 3B  illustrate an optical connector with a waterproof cover according to an embodiment of the present disclosed technology.  FIG. 3A  is a transparent side view of the optical connector with the waterproof cover.  FIG. 3B  is a view of the optical connector with the waterproof cover when viewed from the fitting plane. 
     According to the embodiment, an LC connector  1  is joined to the top end of an optical cable  5  in order to connect the optical cable  5  to an optical module of an apparatus (refer to the LC optical connector  1  illustrated in  FIGS. 1A to 1D ). A ferrule  4  is attached to the top end of the optical connector  1  in order to support an optical fiber in the optical connector  1 . In addition, a ferrule is attached to the optical module connected to the optical connector  1 . By disposing the ferrule  4  of the optical connector  1  so as to face the ferrule of the optical module, optical communication is performed. 
     A latch  2  that engages with the optical module  50  is provided on the upper surface of the LC optical connector  1 . By pressing a trigger lever  3 , the latch  2  is pressed and, therefore, engagement of a protruding portion  6  with an opening  52  of the optical module  50  is released. Thus, by pulling the LC optical connector  1 , the optical cable may be removed from the optical module  50 . A rear housing  12  having a cylindrical shape is integrated into the LC optical connector  1  on the side on which the optical cable  5  is connected. An outlet  14  of the optical cable  5  is made waterproof by using a flexible packing  13 . 
     In addition, the LC optical connector  1  has a front housing  20  integrated therein. The front housing  20  has a cylindrical shape. The front housing  20  is fitted to the rear housing  12  so as to surround the body of the LC optical connector  1 . The front housing  20  has a through-hole at the center thereof. The body of the LC optical connector  1  is located inside of the through-hole. Furthermore, the LC optical connector  1  has an opening  22  in the side surface of the front housing  20  (on the upper side in the drawings). The opening  22  communicates with the through-hole. When the body of the LC optical connector  1  is located inside of the through-hole, the opening  22  is located at the position of the trigger lever  3  of the LC optical connector  1  so that the top end of the trigger lever  3  protrudes through the opening  22 . 
     Still furthermore, the LC optical connector  1  has a waterproof cover  32  integrated therein so that the waterproof cover  32  surrounds the front housing  20  and the rear housing  12 . A plate-like protruding pressure portion  34  is formed on the inner wall of the waterproof cover  32 . The protruding pressure portion  34  protrudes towards the front housing  20  located on the inner side. The protruding pressure portion  34  is secured to the inner wall of the waterproof cover  32 . An opening  38  is formed in the bottom of the inner surface of the waterproof cover  32 . The rear housing  12  is fitted into the opening  38 . A spiral groove is formed on the inner wall of the opening  38  (i.e., an internal screw thread  35  is formed). The internal screw thread  35  engages with an external screw thread  15  formed on the outer wall of the rear housing  12 . By rotating the waterproof cover  32  with respect to the rear housing  12 , the position of the waterproof cover  32  may be changed with respect to the rear housing  12  in the left-right direction of the drawing. The engagement of the internal screw thread  35  of the waterproof cover  32  with the external screw thread  15  of the rear housing  12  effectively makes the connecting portion of the rear housing  12  and the waterproof cover  32  waterproof. 
     According to the present embodiment, in order to increase the waterproof effect, the external screw thread  15  and the internal screw thread  35  are provided on the connecting portion of the rear housing  12  and on the connecting portion of the waterproof cover  32 , respectively. Alternatively, in order to simplify the mechanism, a concave portion and a convex portion may be formed on the fitting portion of the rear housing  12  and on the fitting portion of the waterproof cover  32 , and the rear housing  12  may be slid so as to fit into the waterproof cover  32 . 
       FIG. 4  illustrates the LC optical connector  1  before the LC optical connector  1  is connected to the optical module  50 . As illustrated in  FIG. 4 , a spiral groove (i.e., an internal screw thread  36 ) is formed on the inner wall of a fitting portion of the waterproof cover  32  to the waterproof cover  40  of the apparatus. In addition, a spiral groove (i.e., an external screw thread  46 ) is formed on the outer walls of a fitting portion  44  of the waterproof cover  40  to the waterproof cover  32 . 
       FIG. 5  illustrates the LC optical connector  1  connected to the optical module  50 . In this state, the waterproof cover  40  surrounding the optical module  50  has not yet been fitted to the waterproof cover  32  of the LC optical connector  1 . When, in the state illustrated in  FIG. 5 , the internal screw thread  36  of the waterproof cover  32  is engaged with the external screw thread  46  of the waterproof cover  40  and if the waterproof cover  32  is rotated in the counterclockwise direction when viewed from the apparatus, the screws are tightened up. In contrast, if the waterproof cover  32  is rotated in the clockwise direction, the screws are loosened. At that time, the position of the protruding pressure portion  34  is changed relative to the LC optical connector  1 . 
       FIG. 6  illustrates the waterproof cover  32  and the waterproof cover  40  that are completely joined to each other.  FIGS. 7A and 7B  illustrate the optical module  50  and the waterproof cover  40  of the apparatus.  FIG. 7A  is a transparent view of the optical module  50  and the waterproof cover  40  when viewed from the apparatus.  FIG. 7B  is a perspective view of the waterproof cover  40  of the apparatus when viewed at an angle from the outside of the apparatus. As illustrated in  FIG. 7B , the waterproof cover  40  of the apparatus has a shape in which a low-profile cylinder is stacked on another low-profile cylinder. A waterproof elastic member  48  is attached to the peripheral portion that is close to the chassis. In this way, a waterproof effect is increased. 
     Referring back to  FIG. 5 ,  FIG. 5  also illustrates the LC optical connector  1  removed from the optical module  50  after the waterproof cover  32  is rotated and removed from the apparatus. In this state, the protruding pressure portion  34  of the inner wall of the waterproof cover  32  is located so as to press the trigger lever  3  of the LC optical connector  1  downward. At that time, the latch  2  is also pressed downward, and the protruding portion  6  of the latch  2  that hangs from the opening  52  is removed from the opening  52 . If the LC optical connector  1  is continuously pulled together with the waterproof cover  32 , the LC optical connector  1  may be removed from the optical module  50 . 
       FIGS. 8A to 8C  are schematic illustrations of the mechanism of the optical connector according to the present embodiment. A positional relationship between the protruding pressure portion  34  and the trigger lever  3  in accordance with rotation of the waterproof cover  32  is illustrated in  FIGS. 8A to 8C . The left sections of  FIGS. 8A to 8C  illustrate an LC optical connector with a waterproof cover when viewed from the connecting plane of the apparatus. The right sections of  FIGS. 8A to 8C  illustrate a relative positional relationship between the protruding pressure portion  34  of the waterproof cover  32  and the LC optical connector  1 . If, as illustrated in  FIGS. 8A to 8C , the waterproof cover  32  is rotated in the clockwise direction when viewed from the apparatus, the screws of the waterproof cover  32  and the waterproof cover  40  are loosened. 
     If, as may be seen from comparison of the left sections of  FIGS. 8A and 8B , the waterproof cover  32  is rotated by an angle of θ 1  in the clockwise direction when viewed from the apparatus, the position of the protruding pressure portion  34  is moved towards the trigger lever  3  in the rightward direction by a distance of Y 1  as may be seen from comparison of the right sections of  FIGS. 8A and 8B . Thereafter, if, as may be seen from comparison of the left sections of  FIGS. 8B and 8C , the waterproof cover  32  is further rotated by an angle of θ 2  in the clockwise direction when viewed from the apparatus, the position of the protruding pressure portion  34  is further moved towards the trigger lever  3  in the rightward direction by a distance of Y 2  as may be seen from comparison of the right sections of  FIGS. 8B and 8C . In addition, the protruding pressure portion  34  presses the trigger lever  3  downward while contacting the trigger lever  3 . 
     By rotating the waterproof cover  32  about the axis of the LC optical connector  1  in this manner, the protruding pressure portion  34  is moved with respect to the trigger lever  3  in the rotational direction and the rotation axis direction (i.e., in the rightward direction in  FIGS. 8A to 8C ). Finally, the protruding pressure portion  34  reaches the position of the trigger lever  3 , and the trigger lever  3  is pressed downward by the protruding pressure portion  34 . As a result, the latch  2  is also pressed downward, and the hook of the protruding portion  6  of the latch  2  is released. The design is such that, in this case, the internal screw thread  36  of the waterproof cover  32  is removed from the external screw thread  46  of the waterproof cover  40 . Since the protruding pressure portion  34  is moved towards the trigger lever  3  in the rotational direction and the rotation axis direction in this manner, the surface of the protruding pressure portion  34  has a curved shape so that the protruding pressure portion  34  is in smooth contact with the top end of the trigger lever  3 . In addition, in order to increase the contact area of the protruding pressure portion  34  with the trigger lever  3 , it is desirable that the shape be elliptical rather than generally circular. 
     The manufacturing steps of the LC optical connector with a waterproof cover according to the present embodiment are described next with reference to  FIGS. 9A to 9C ,  FIGS. 10A to 10C , and  FIGS. 11A to 11C . First, as illustrated in  FIG. 9A , the optical cable  5  is inserted into a hole of the packing  13  in the rear housing  12 . Thereafter, the optical cable  5  is inserted into the waterproof cover  32 . If an LC optical connector with a waterproof cover is attached to the other end of the optical cable  5 , a rear housing  12  and the waterproof cover  32  are disposed so as to face in the opposite direction and the optical cable  5  is inserted in a similar manner. As illustrated in  FIG. 9B , the LC optical connector  1  is connected to the top end of the optical cable  5 . As illustrated in  FIG. 9C , a removal prevention ring  7  is fitted into the body of the LC optical connector  1  and is secured to the body. 
     As illustrated in  FIG. 10A , the optical cable  5  is pulled until the removal prevention ring  7  reaches the position of a stopper  16  of the rear housing  12 . In this way, the LC optical connector  1  is fitted into the rear housing  12 . As illustrated in  FIGS. 10B and 10C , the body of the LC optical connector  1  is inserted into a through-hole  24  located at the center of the front housing  20 , and the front housing  20  is fitted into the rear housing  12  so that a positioning hole  26  formed in the front housing  20  is fitted into a positioning protrusion  17  formed on an inner peripheral surface of the rear housing  12 . At that time, the orientations are aligned so that the top end of the trigger lever  3  of the LC optical connector  1  protrudes through the opening  22  formed in the side surface of the front housing  20 . 
       FIGS. 11A to 11C  illustrate the steps of fitting the waterproof cover  32 . As illustrated in  FIGS. 11A and 11B , the body of the rear housing  12  is inserted into the opening  38  that corresponds to the inner bottom portion of the waterproof cover  32  having the optical cable  5  disposed therein. Thereafter, the internal screw thread  35  formed in the inner wall of the opening  38  is engaged with the external screw thread  15  formed in the outer wall of the rear housing  12 , and the waterproof cover  32  is rotated with respect to the rear housing  12 . Thus, the waterproof cover  32  is moved to the position of a ring  18  and a packing  19  disposed in the middle of the body of the rear housing  12 . Subsequently, as illustrated in  FIG. 11C , the protruding pressure portion  34  is inserted and secured to a groove formed in the inner wall of the waterproof cover  32 . In this way, the LC optical connector  1  is produced. 
     Note that while the present embodiment has been described with reference to an LC optical connector having a latch, the present embodiment is applicable to another type of communication cable having a connector with a latch. 
     All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.