Abstract:
The present disclosure relates generally to an optical connector kit including parts constituting an optical connector. Certain embodiments relate to an optical connector kit having an optical fiber with a ferrule, a plurality of connector units, and a storage case including an upper and lower housing.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to and the benefit of Japanese Patent Application No. 2010-047875, filed on Mar. 4, 2010, in the Japan Patent Office. The disclosure of the foregoing application is incorporated herein in its entirety by reference. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    The present invention relates to an optical connector kit including parts constituting an optical connector, which facilitates an operation of attaching an optical connector to the distal end of an optical fiber on-site. 
         [0004]    2. Description of the Related Art 
         [0005]    In recent years, to realize construction of access networks, local optical wiring or the like using optical fibers, there has been a demand to attach an optical connector to the distal end of an optical fiber on-site where workability is restricted as compared to manufacturing factories. 
         [0006]    Generally, an optical connector can have a lot of parts. During the attachment of an optical connector to the distal end of an optical fiber, the optical connector parts may need to be first manually passed through the optical fiber one by one. 
         [0007]    Thus, particularly when the attachment operation is performed on-site, operation errors often occur when some of the connector parts are not passed through the optical fiber, or when the connector parts are passed through the optical fiber in a wrong order or a wrong direction. It takes time and care to pass the connector parts through the optical fiber even though it is a simple operation, thereby deteriorating the workability. 
         [0008]    To solve the problem, Japanese Patent Application Publication No. 2005-25132 discloses a case which stores a plurality of connector parts to be passed through an optical fiber in advance when an optical connector is attached to the distal end of the optical fiber, the connector parts being arranged in a line in the order in which the connector parts are passed through the optical fiber. 
         [0009]    Conventional optical connector parts cases attempt to prevent the occurrence of the operation error when some of the connector parts are not passed through the optical fiber or when the connector parts are passed in a wrong order or a wrong direction. 
       SUMMARY 
       [0010]    Conventional optical connector parts case designs can have a problem in that each set of a type of optical connectors requires a corresponding optical connector part case. Thus, a variety of optical connector part cases are required to be kept on hand for various sets of optical connector parts. Accordingly, manufacturing equipment investment increases and inventory control is complicated, thereby contributing to cost increases. 
         [0011]    Accordingly, there is a need for an optical connector kit in which a variety of optical connector parts are stored in one type of case. 
         [0012]    In one embodiment, there is provided an optical connector kit. The optical connector kit comprises a ferrule-with-optical-fiber obtained by mounting a short optical fiber into a ferrule in advance and polishing an end surface of said optical fiber, a plurality of connector parts (insertion parts) to be passed through another optical fiber in advance before a rear end of said short optical fiber and a distal end of said another optical fiber are fusion-spliced, and a storage case for storing all connector parts constituting an optical connector, which include the ferrule-with-optical-fiber and the insertion parts, wherein the insertion parts are arranged in a line in the order in which the insertion parts are passed through said another optical fiber, the storage case comprises a lower housing and an upper housing in an openable and closeable manner, optical fiber insertion ports, through which said another optical fiber can be inserted from outside on one side of the lower housing to outside on the other side of the lower housing through the insertion parts, are provided in both side walls of the lower housing, insertion part storage portions for storing the insertion parts are provided in both the lower housing portion and the upper housing portion, and the insertion parts are stored in the insertion part storage portion, and held by sandwiching between the lower housing portion and the upper housing portion. 
         [0013]    In another embodiment, tapered shapes for guiding said second optical fiber to be inserted are formed between adjacent insertion part storage portions. 
         [0014]    In yet another embodiment, the storage case comprises the lower housing having a bottom surface raised by a surrounding side wall and the upper housing having a lid surface to be coupled together in an openable and closeable manner, wherein the lower housing comprises a flange around a lower portion of the side wall, the upper housing comprises a flange in a surrounding portion, and the upper housing and the lower housing comprise a lower engagement portion and an upper engagement portion engageable with each other. 
         [0015]    In yet another embodiment, the flanges of the lower housing and the flange of the upper housing are not brought into close contact with each other when the storage case is closed, so as to be a tab when the storage case is opened. 
         [0016]    In yet another embodiment, a storage portion for the ferrule with optical fiber and a storage portion for the insertion parts are formed so as to bulge downward in the bottom surface of the lower housing, and wherein a bulging depth of the storage portion for said individual insertion part is smaller than a height of said corresponding insertion part to be stored therein. 
         [0017]    For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described above and as further described below. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. 
         [0018]    All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    These and other aspects of the invention will be readily apparent from the following description and from the appended drawings (not to scale), which are meant to illustrate and not to limit embodiments of the invention, and in which: 
           [0020]      FIG. 1  is a plan view illustrating a state in which a storage case storing all connector parts constituting an optical connector is closed according to one embodiment of an optical connector kit; 
           [0021]      FIG. 2  is a plan view illustrating a state in which the optical connector kit in  FIG. 1  is opened to a partially open state; 
           [0022]      FIG. 3  is a plan view illustrating a state in which the optical connector kit in  FIG. 1  is opened to a fully open state; 
           [0023]      FIG. 4  is a plan view illustrating a state in which an empty storage case storing no connector parts is opened to a fully open state; 
           [0024]      FIG. 5  is a right side view of the storage case in  FIG. 4 ; 
           [0025]      FIG. 6  is a sectional view illustrating one embodiment of a ferrule-with-optical-fiber used for the optical connector kit; 
           [0026]      FIG. 7  is a sectional view illustrating the length of each portion of a short optical fiber used for the ferrule-with-optical-fiber in  FIG. 6 ; and 
           [0027]      FIG. 8  is a sectional view illustrating one embodiment of an optical connector obtained by assembling the optical connector kit. 
       
    
    
     EXPLANATION OF NUMERICAL REFERENCES 
       [0000]    
       
           1 : optical connector kit 
           5 : storage case 
           10 : ferrule-with-optical-fiber 
           11 : ferrule 
           12 : capillary 
           13 : micro hole 
           15 : flange portion 
           16 : coated portion passage hole 
           18 : short optical fiber 
           18   a:  bare optical fiber portion 
           18   b:  coated optical fiber 
           18   c:  splicing extra length (extended optical fiber portion) 
           20 : connector part (insertion part) 
           21 : boot 
           22 : sleeve 
           23 : stop ring 
           24 : clip 
           25 : spring 
           28 : reinforcement sleeve 
           30 : other connector part (other part) 
           31 : plug frame 
           32 : cap 
           40 : holding member 
           41 : cap 
           42 : pulling portion 
           50 : lower housing 
           51 : bottom surface 
           52 : side wall 
           53 : flange 
           54 : tab 
           55 : upper housing 
           56 : lid surface 
           57 : flange 
           58 : tab 
           60 : ferrule-with-optical-fiber storage portion 
           61 : ferrule storage portion (the lower portion) 
           61 ′: ferrule storage portion (the upper portion) 
           62 : optical fiber protection portion 
           65 : holding member storage portion (the lower portion) 
           65 ′: holding member storage portion (the upper portion) 
           66 : cap storage portion 
           67 : pulling portion storage portion 
           68 : finger hooking portion 
           70 : insertion part storage portion (the lower portion) 
           70 ′: insertion part storage portion (the upper portion) 
           71 : boot storage portion (the lower portion) 
           71 ′: boot storage portion (the upper portion) 
           72 : sleeve storage portion (the lower portion) 
           72 ′: sleeve storage portion (the upper portion) 
           73 : stop ring storage portion (the lower portion) 
           73 ′: stop ring storage portion (the upper portion) 
           74 : clip storage portion (the lower portion) 
           74 ′ : clip storage portion (the upper portion) 
           75 : spring storage portion (the lower portion) 
           75 ′: spring storage portion (the upper portion) 
           76   a,   76   b:  optical fiber insertion port 
           78 : reinforcement sleeve storage portion (the lower portion) 
           78 ′: reinforcement sleeve storage portion (the upper portion) 
           79 : finger hooking portion 
           80 : other part storage portion 
           81 : plug frame storage portion 
           82 : finger hooking portion 
           85 : cap storage portion 
           86 : finger hooking portion 
           91 : first region 
           92 : second region 
           94 : a plurality of small holes 
           95 , 97 : lower engagement portion 
           96 , 98 : upper engagement portion 
           100 : optical connector 
           101 : optical fiber 
           111 , 111 ′: tapered portion 
       
     
       DETAILED DESCRIPTION OF EMBODIMENTS 
       [0100]    The embodiments according to the present invention will now be explained in detail with reference to the drawings, but the present invention is not intended to be limited to these embodiments and many different embodiments can be implemented. 
         [0101]    In some embodiments, an optical connector kit can include a ferrule-with-optical-fiber obtained by mounting a short optical fiber into a ferrule in advance and polishing an end surface, a plurality of connector parts (insertion parts) to be passed through another optical fiber in advance before a rear end of said short optical fiber and a distal end of said another optical fiber can be fusion-spliced, and a storage case for storing all connector parts constituting an optical connector, which can include the ferrule-with-optical-fiber and the insertion parts. While connector parts used for the fusion splicing (parts for use in fusion splicing) including the ferrule-with-optical-fiber and the insertion parts can be removed from the storage case, the storage case can hold other connector parts in a stored state. Thus, the storage case can be easily carried to a site. There is also a reduced possibility that a user will forget to carry some of the connector parts constituting the optical connector. 
         [0102]    The storage case for storing all the connector parts constituting the optical connector allows a variety of optical connector parts to be stored in one type of storage case. Thus, equipment investment decreases and inventory control is simplified, so that the optical connector kit can be provided at a lower price. 
         [0103]    Since the ferrule-with-optical-fiber obtained by mounting the short optical fiber into the ferrule in advance and polishing the end surface is employed, an operation of fusion-splicing the rear end of the short optical fiber and the distal end of said another optical fiber on-site is facilitated. 
         [0104]    Moreover, the storage case can hold the other connector parts in a stored state while the parts for use in fusion splicing can be removed therefrom. Thus, the other connector parts used after the fusion-splicing operation are not possibly missing from the storage case during the fusion-splicing operation. 
         [0105]      FIG. 1  is a plan view of an embodiment of an optical connector kit illustrating a state in which a storage case storing all connector parts is closed.  FIG. 2  is a plan view illustrating a state in which the storage case is opened to a partially open state.  FIG. 3  is a plan view illustrating a state in which the storage case is opened to a fully open state.  FIG. 4  is a plan view illustrating a state in which an empty storage case storing no connector part is opened to a fully open state. 
         [0106]    In the optical connector kit  1 , all the connector parts which can constitute an optical connector, which can include a ferrule-with-optical-fiber  10  obtained by mounting a short optical fiber into a ferrule in advance and polishing an end surface, can be stored in a storage case  5 . 
         [0107]    As shown in  FIG. 6 , the ferrule-with-optical-fiber  10  can include a ferrule  11  having a capillary  12  and a flange portion  15  for holding a rear end portion of the capillary  12 . A short optical fiber  18  having a bare optical fiber portion  18   a,  from which a coating is removed, at the distal end can be mounted into the ferrule  11 , and the end surface can be polished. 
         [0108]    A micro hole  13  can be formed throughout the capillary  12  from the distal end to the rear end to store the bare optical fiber portion  18   a  of the short optical fiber  18 . 
         [0109]    A coated portion passage hole  16  can be formed in the flange portion  15  to store a coated optical fiber  18   b.    
         [0110]    When the bare optical fiber portion  18   a  is stored in and secured to the micro hole  13  of the capillary  12 , and the coated optical fiber  18   b  leading from the bare optical fiber  18   a  is stored in and secured to the coated portion passage hole  16 , the short optical fiber  18  can extend backward by a required splicing extra length  18   c  from the coated portion passage hole  16  of the flange portion  15 . 
         [0111]    The splicing extra length  18   c  extending backward from the flange portion  15  can have at least a length required by an unillustrated fusion splicing apparatus which optically connects the rear end of the splicing extra length  18   c  and the distal end of another optical fiber  101  (see  FIG. 1 ) to which the rear end can be optically connected. 
         [0112]    Although the splicing extra length  18   c  of the short optical fiber  18  may be left as the coated optical fiber  18   b,  a coating in the rear end portion may be removed as shown in  FIGS. 6 and 7 . 
         [0113]    As a countermeasure against strength deterioration occurring when the short optical fiber  18  is kept for a long period at normal temperature and normal humidity when stored in the optical connector kit  1 , and to improve static fatigue characteristics, a coating of metal or carbon, that is, a hermetic coating such as a metal or carbon coating can preferably be applied to the outer periphery of the short optical fiber  18 . 
         [0114]    In addition to the ferrule-with-optical-fiber  10 , the connector parts constituting the optical connector include a plurality of connector parts (insertion parts)  20  to be passed through the optical fiber  101  in advance before the rear end of the short optical fiber  18  and the distal end of the optical fiber  101  can be fusion-spliced as shown in  FIG. 3 . 
         [0115]    That is, the insertion parts  20  can include a boot  21 , a sleeve  22 , a stop ring  23 , a clip  24  and a spring  25  as shown in  FIG. 3 . The ferrule-with-optical-fiber  10 , the insertion parts  20 , and a reinforcement sleeve  28  constitute connector parts that can be used for fusion splicing (parts for use in fusion splicing). 
         [0116]    The reinforcement sleeve  28  can reinforce a fusion-spliced portion obtained when the rear end of the short optical fiber  18  and the distal end of the optical fiber  101  are fusion-spliced. A heat-shrinkable tube including a reinforcement member of metal or the like and thermoplastic resin can constitute the reinforcement sleeve  28 . 
         [0117]    The connector parts constituting the optical connector can also include other connector parts (other parts)  30  in addition to the parts for use in fusion splicing  10 ,  20  and  28 . To be more specific, the other connector parts (the other parts)  30  can include a plug frame  31  and a cap  32  as shown in  FIG. 3 . 
         [0118]    The storage case  5  in which all the connector parts constituting the optical connector as described above are stored can also store a holding member  40  for holding the ferrule-with-optical-fiber  10  during fusion splicing. 
         [0119]    The holding member  40  can include a cap  41  where the ferrule  11  of the ferrule-with-optical-fiber  10  can be inserted from the distal end, and a pulling portion  42  extending from a bottom portion of the cap  41 . The holding member  40  can be integrated with the ferrule-with-optical-fiber  10  when the ferrule  11  is inserted into the cap  41 . The rear end of the short optical fiber  18  of the ferrule-with-optical-fiber  10  and the distal end of the optical fiber  101  can be fusion-spliced in this state. After that, the holding member  40  can be detached from the ferrule  11 . 
         [0120]    As shown in  FIG. 5 , the storage case  5  can include a lower housing  50  having a bottom surface  51  raised by a surrounding side wall  52 , and an upper housing  55  having a lid surface  56 , which are coupled together in an openable and closeable manner. 
         [0121]    The lower housing  50  can include a flange  53  around a lower portion of the side wall  52 . The upper housing  55  can include a flange  57  at the lid surface  56 . Lower engagement portions  95  and  97  of the lower housing  50 , and upper engagement portions  96  and  98  of the upper housing  55  can engage with each other. 
         [0122]    The storage case  5  also can include tabs  54  and  58  which can be gripped when the storage case  5  is opened, by the flange  53  of the lower housing  50  and the flange  57  of the upper housing  55  not being brought into close contact with each other when the storage case  5  is closed. 
         [0123]    In the storage case  5 , a ferrule-with-optical-fiber storage portion  60  for storing the ferrule-with-optical-fiber  10 , a holding member storage portion (the lower portion)  65  for storing the holding member  40  mounted on the ferrule-with-optical-fiber storage portion  60 , an insertion part storage portion (the lower portion)  70  for storing the insertion parts  20  in a line in the order in which the insertion parts  20  are passed through the optical fiber, a reinforcement sleeve storage portion (the lower portion)  78  for storing the reinforcement sleeve  28 , and an other part storage portion  80  for storing the other connector parts (the other parts)  30  can be formed so as to bulge downward in the bottom surface  51  of the lower housing  50 . 
         [0124]    The ferrule-with-optical-fiber storage portion  60  can include a ferrule storage portion (the lower portion)  61  where the ferrule  11  of the ferrule-with-optical-fiber  10  can be stored, and an optical fiber protection portion  62  for forming a space around the optical fiber portion (the splicing extra length)  18   c  extending from the rear end of the ferrule  11  when the ferrule  11  is stored in the ferrule storage portion (the lower portion)  61 . 
         [0125]    The optical fiber protection portion  62  protects, with the space as a barrier, the splicing extra length  18   c  which may have lower strength since the splicing extra length  18   c  extends from the rear end of the ferrule  11  when the ferrule-with-optical-fiber  10  is stored in the ferrule-with-optical-fiber storage portion  60 . 
         [0126]    The holding member storage portion (the lower portion)  65  can include a cap storage portion  66  where the cap  41  of the holding member  40  into which the ferrule  11  of the ferrule-with-optical-fiber  10  is inserted can be stored, and a pulling portion storage portion  67  where the pulling portion  42  extending from the bottom portion of the cap  41  can be stored. 
         [0127]    The holding member storage portion (the lower portion)  65  can also include a finger hooking portion  68  for allowing a user to hook his finger around the holding member  40 , to remove the holding member  40  stored in the holding member storage portion (the lower portion)  65 . That is, a user can insert his finger into the finger hooking portion  68  to pull up the pulling portion  42  of the holding member  40 , so that the holding member  40  and the ferrule-with-optical-fiber  10  integrated therewith are removed from the storage case  5 . 
         [0128]    The insertion part storage portion (the lower portion)  70  can include a boot storage portion (the lower portion)  71  where the boot  21  can be stored, a sleeve storage portion (the lower portion)  72  where the sleeve  22  can be stored, a stop ring storage portion (the lower portion)  73  where the stop ring  23  can be stored, a clip storage portion (the lower portion)  74  where the clip  24  can be stored, and a spring storage portion (the lower portion)  75  where the spring  25  can be stored. 
         [0129]    The storage case  5  can include optical fiber insertion ports  76   a  and  76   b,  through which the optical fiber  101  can be inserted from outside on one side of the storage case  5  to outside on the other side of the storage case  5  through the connector parts (the insertion parts)  20  (the boot  21 , the sleeve  22 , the stop ring  23 , the clip  24 , the spring  25 ) stored in a line, in the both side walls of the storage case  5  on an extension of the insertion part storage portion  70 . 
         [0130]    The reinforcement sleeve  28  can be stored in the reinforcement sleeve storage portion (the lower portion)  78 . The reinforcement sleeve storage portion (the lower portion)  78  can include a finger hooking portion  79  for allowing a user to hook his finger around the reinforcement sleeve  28 , to remove the reinforcement sleeve  28  stored in the reinforcement sleeve storage portion (the lower portion)  78 . That is, a user inserts his finger into the finger hooking portion  79  to pull up the reinforcement sleeve  28 , so that the reinforcement sleeve  28  can be removed from the storage case  5 . 
         [0131]    The other part storage portion  80  can include a plug frame storage portion  81  where the plug frame  31  can be stored, and a cap storage portion  85  where the cap  32  can be stored. The plug frame storage portion  81  can include a finger hooking portion  82  for allowing a user to hook his finger around the plug frame  31 , to remove the plug frame  31  stored in the plug frame storage portion  81 . That is, a user inserts his finger into the finger hooking portion  82  to pull up the plug frame  31 , so that the plug frame  31  can be removed from the storage case  5 . 
         [0132]    The cap storage portion  85  can include a finger hooking portion  86  for allowing a user to hook his finger around the cap  32 , to remove the cap  32  stored in the cap storage portion  85 . That is, a user can insert his finger into the finger hooking portion  86  to pull up the cap  32 , so that the cap  32  can be removed from the storage case  5 . 
         [0133]    The storage case  5  as described above can be molded of appropriate synthetic resin such as PET (polyethylene terephthalate) resin. In this case, by making the storage case  5  transparent, all the connector parts  10 ,  20 ,  28  and  30  stored therein can be confirmed from outside the storage case  5  without opening the storage case  5 . 
         [0134]    The storage case  5  also can include a first region  91  for storing the parts for use in fusion splicing  10 ,  20  and  28  on a side apart from a coupled portion between the lower housing  50  and the upper housing  55 , and a second region  92  for storing the other connector parts  30  on a side close to the coupled portion as shown in  FIGS. 1 to 3 . 
         [0135]    The upper housing  55  of the storage case  5  can be bent at a border portion between the first region  91  and the second region  92 . That is, a plurality of small holes  94  can be formed at a predetermined position of the upper housing  55  including a portion of the lid surface  56 . 
         [0136]    Accordingly, when the upper housing  55  of the storage case  5  is bent along the plurality of small holes  94 , only the first region  91  can be opened. In the storage case  5 , the lower housing  50  and the upper housing  55  can be opened and closed, and the upper housing  55  can be switched between a partially open state in which the storage region for the parts for use in fusion splicing of the lower housing  50  (the first region  91 ) is opened, and a fully open state in which the entire region of the lower housing  50  is opened. 
         [0137]    The storage case  5  further can include the lower engagement portions  95  and the upper engagement portions  96  engageable with each other in the second region  92  of the lower housing  50 , and the second region  92  of the upper housing  55  (see  FIGS. 1 ,  2  and  4 ). 
         [0138]    The lower engagement portions  95  and the upper engagement portions  96  engage with each other when the storage case  5  is closed (see  FIG. 1 ). When the upper housing  55  is opened to the partially open state, the lower engagement portions  95  and the upper engagement portions  96  still maintain the engagement state (see  FIG. 2 ). When the upper housing  55  is opened to the fully open state, the engagement state is released to enable the fully open state. 
         [0139]    The storage case  5  may be switched not only between the partially open state in which only the first region  91  is opened and the fully open state in which both the first region  91  and the second region  92  are opened as described above, but among three or more open states including the partially open state and the fully open state. 
         [0140]    The upper housing  55  of the storage case  5  can include an insertion part storage portion (the upper portion)  70 ′, a reinforcement sleeve storage portion (the upper portion)  78 ′, a ferrule storage portion (the upper portion)  61 ′, and a holding member storage portion (the upper portion)  65 ′. 
         [0141]    The insertion part storage portion (the upper portion)  70 ′ can include a boot storage portion (the upper portion)  71 ′ where the boot  21  can be stored, a sleeve storage portion (the upper portion)  72 ′ where the sleeve  22  can be stored, a stop ring storage portion (the upper portion)  73 ′ where the stop ring  23  can be stored, a clip storage portion (the upper portion)  74 ′ where the clip  24  can be stored, and a spring storage portion (the upper portion)  75 ′ where the spring  25  can be stored. 
         [0142]    A variety of optical connectors are used on-site. For example, an optical connector for a fusion length of 5 mm has a stop ring outermost diameter of, e.g., φ4.5 mm, and an optical connector for a fusion length of 10 mm has a stop ring outermost diameter of, e.g., φ6.3 mm. The two stop ring outermost diameters have a difference of 1.8 mm. For example, if a storage portion having an appropriate shape for the stop ring having the outermost diameter of φ6.3 mm is used, the optical fiber can be difficult to insert into the stop ring having the outermost diameter of φ4.5 mm. In some embodiments, however, the parts are held by the storage portion of the lower housing and the storage portion of the upper housing, so that the misalignment difference is reduced by half to 0.9 mm. Also, the center to insert the optical fiber is maintained. Thus, even when two parts having different outer diameters are stored in the same storage portion, the optical fiber can be easily inserted into the parts. 
         [0143]    When the upper housing is in an open state, each insertion part in the insertion part pressing portion of the upper housing is exposed above the lower housing. Thus, each insertion part can be easily removed even when no finger hooking portion is provided in each insertion part storage portion. 
         [0144]    A tapered portion  111  can be provided on the both sides of each part storage portion of the insertion part storage portion (the lower portion)  70  to guide said another optical fiber  101  to be inserted. A tapered portion  111 ′ can be provided on the both sides of each part pressing portion of the insertion part storage portion (the upper portion)  70 ′ to guide said another optical fiber  101  to be inserted. The structure to sandwich the insertion parts, and the structure to guide said another optical fiber  101  to be inserted allows a variety of optical connector kits to be stored in one type of storage case  5 , so that the optical connector kit can be provided at a lower price. 
         [0145]    Next, an optical connector assembling method for assembling an optical connector using the above optical connector kit  1  will be described. 
         [0146]    First, in the optical connector kit  1 , the ferrule-with-optical-fiber  10  can be stored in the ferrule-with-optical-fiber storage portion  60 . The holding member  40  integrated with the ferrule-with-optical-fiber  10  can be stored in the holding member storage portion (the lower portion)  65 . The insertion parts  20  (the boot  21 , the sleeve  22 , the stop ring  23 , the clip  24 , the spring  25 ) can be stored in the insertion part storage portion (the lower portion)  70 . The reinforcement sleeve  28  can be stored in the reinforcement sleeve storage portion (the lower portion)  78 . The other connector parts (the other parts)  30  (the plug frame  31 , the cap  32 ) can be stored in the other part storage portion  80  (see  FIGS. 3 and 4 ). 
         [0147]    The lower engagement portions  95  and  97  of the lower housing  50 , and the upper engagement portions  96  and  98  of the upper housing  55  can be engageable with each other (see  FIG. 1 ). 
         [0148]    The lower engagement portions  95  provided in the second region  92  of the lower housing  50 , and the upper engagement portions  96  provided in the second region  92  of the upper housing  55  can engage with each other at this point. 
         [0149]    When the storage case  5  is in a closed state as described above, the optical fiber  101  can be inserted into the storage case  5  from the optical fiber insertion port  76   a  near the rear end of the boot  21 , and can project to outside the storage case  5  from the optical fiber insertion port  76   b  on the other side. Accordingly, the insertion parts  20  stored in a line in the storage case  5  can be passed through the optical fiber  101  in the order of the line (in the order of the boot  21 , the sleeve  22 , the stop ring  23 , the clip  24  and the spring  25 ). 
         [0150]    Subsequently, a user can hook his finger around the tabs  54  and  58  of the storage case  5  to pull up the upper housing  55 . Since the upper engagement portions  96  provided in the second region  92  of the upper housing  55  engage with the lower engagement portions  95  provided in the second region  92  of the lower housing  50 , the portion of the second region  92  can be held so as not to be pulled up. 
         [0151]    The upper housing  55  can be thereby bent along the plurality of small holes  94  in the border portion between the first region  91  and the second region  92  due to the force to pull up the upper housing  55  by the finger hooked around the tab  58 , and the force to hold the upper housing  55  so as not to be pulled up by the upper and lower engagement portions  96  and  95 . Accordingly, in the storage case  5 , only the first region  91  is opened while the second region  92  is maintained in a closed state (see  FIG. 2 ). 
         [0152]    The parts for use in fusion splicing  10 ,  20 , and  28  arranged in the first region  91  can be thereby removed from the storage case  5 . The other connector parts  30  arranged in the second region  92  are still held in the storage case  5  in a closed state. 
         [0153]    The ferrule-with-optical-fiber  10  integrated with the holding member  40  can be removed from the storage case  5 . The rear end of the short optical fiber  18  of the ferrule-with-optical-fiber  10 , and the distal end of the optical fiber  101  can be fusion-spliced by using an appropriate fusion splicing apparatus. 
         [0154]    To perform the fusion splicing, the coating in a portion with required length at the rear end of the splicing extra length  18   c  of the short optical fiber  18 , and the coating in a portion with required length at the distal end of the optical fiber  101  are first removed. Subsequently, the rear end of the short optical fiber  18 , and the distal end of the optical fiber  101  are disposed facing each other. The short optical fiber  18  and the optical fiber  101  are aligned based on the position of a core or a clad. Thereafter, the fusion splicing is performed. 
         [0155]    In this case, if the coating in the rear end portion of the splicing extra length  18   c  of the short optical fiber  18  has been removed in advance, it can save time to remove the coating. Thus, the operation time can be reduced. The reinforcement sleeve  28  constituted by the heat-shrinkable tube including a reinforcement member of metal or the like and thermoplastic resin can be attached to the fusion-spliced portion to reinforce the fusion-spliced portion. 
         [0156]    The upper housing  55  of the storage case  5  can be further pulled up to release the engagement of the upper and lower engagement portions  96  and  95 , so that the second region  92  can be opened (see  FIG. 3 ). Accordingly, the other connector parts (the other parts)  30  arranged in the second region  92  can be removed from the storage case  5 . 
         [0157]    The insertion parts  20  passed through the optical fiber  101  (the boot  21 , the sleeve  22 , the stop ring  23 , the clip  24 , the spring  25 ) and the other connector parts (the other parts)  30  (the plug frame  31 , the cap  32 ) are assembled in a predetermined assembling order. Accordingly, an optical connector  100  as shown in  FIG. 8  is obtained. 
         [0158]    The optical connector kit according to some embodiments has been specifically described above along with the optical connector assembling method using the optical connector kit. However, it should be noted that some embodiments are not limited to the aforementioned embodiment, and various design changes may be made therein. 
         [0159]    For example, although not shown in the drawings, an opening and closing mechanism for the lower housing  50  and the upper housing  55  of the storage case  5  may employ any conventionally-known mechanism such as a hinge type mechanism or a fitting type mechanism. In this case, the storage case  5  may be also opened to the partially open state or the fully open state as needed. 
         [0160]    Although the embodiments described herein are based on an LC type connector part, the embodiments may be adapted for any of an MU type, SC type, FC type connector parts or the like. Also, the embodiments can be adapted for other optical connectors not listed herein, but having similar structure. 
         [0161]    Although this invention has been disclosed in the context of certain embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications thereof. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.