Patent Publication Number: US-2023152528-A1

Title: Tool for plug, slider, plug, and cable with plug

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 16/806,074, filed on Mar. 2, 2020, which claims the benefit of priority to Japanese Patent Application No. 2019-038956, filed on Mar. 4, 2019, the entire contents of which are hereby incorporated by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a tool for a plug, a slider, a plug, and a cable with plug. 
     2. Description of the Background 
     An optical fiber cable and an optical module such as a receiver or a transmitter, or other optical fiber cable, are connected to each other via an adapter (including a so-called receptacle). A plug configured to be fitted to the adapter is provided at a terminal part of the optical fiber cable. In a device such as a communication device on which optical modules are mounted or a plugboard connecting between optical fiber cables, a plurality of adapters may be densely disposed so as to implement a compact device. There is a known tool and a plug with a tool which facilitate fitting and/or removing the plug to/from densely disposed adapters (for example, see Japanese Patent Unexamined Patent Application No. 2002-350677, which is hereinafter referred to as “Patent Literature 1”, and Japanese Patent Unexamined Patent Application No. 2005-17602, which is hereinafter referred to as “Patent Literature 2”). 
     The plug disclosed in Patent Literature  1  includes: a plug body configured to be inserted into (fitted to) an adapter, and a knob shiftably supported on the plug body. By the knob being shifted in the removal direction relative to the plug body which is inserted into (fitted to) the adapter, the fitting between the adapter and the plug body is canceled, and the plug body is pulled out from the adapter. The plug insert-remove tool disclosed in Patent Literature  1  includes: a grip part; an insert tool provided at one end in the longitudinal direction of the grip part; and a remove tool provided at the other end. 
     The insert tool includes: a knob retaining part configured to embracingly retain a knob; and a boot retaining part configured to embracingly retain a boot provided adjacent to the rear edge of the knob. The knob retaining part is provided with a projection part configured to abut on the rear end of the knob. By the grip part being pushed in while the projection part is abutting on the rear end of the knob, the plug body is inserted into the adapter. The remove tool includes: a boot retaining part configured to embracingly retain the boot; and an engaging projection part extending from the boot retaining part and configured to cover the knob. By the grip part being pulled while the engaging projection part is engaging with the knob, the knob is shifted in the removal direction. This cancels the insertion (fitting) between the adapter and the plug body, and the plug body is pulled out from the adapter. 
     The plug with a remove tool disclosed in Patent Literature  2  includes a plug body configured to be fitted to an adapter, and a knob shiftably supported on the plug body. By the knob being shifted in the removal direction relative to the plug body which is fitted to the adapter, the fitting between the adapter and the plug body is canceled, and the plug body is pulled out from the adapter. The plug with a remove tool disclosed in Patent Literature 2 further includes a pull-tab. 
     The pull-tab includes: a cover part configured to embracingly retain the knob and the boot on its leading side; and a pull part on its trailing side. The cover part is provided with a catch projection configured to engage with the knob. By the pull part being pulled while the catch projection is engaging with the knob, the knob is shifted in the removal direction. This cancels the fitting between the adapter and the plug body, and the plug body is pulled out from the adapter. 
     In the plug insert tool disclosed in Patent Literature 1, the knob retaining part configured to embracingly retain the knob is disposed on the outer side of the plug. In the plug extraction tool, the engaging projection part configured to cover the knob is disposed on the outer side of the plug. That is, while a plurality of adapters may be densely disposed, Patent Literature  1  needs space for accommodating the knob retaining parts and the engaging projection parts between the plugs fitted to the adapters. Thus, Patent Literature  1  is not applicable to densely disposed adapters. 
     In the pull-tab of the plug with a remove tool disclosed in Patent Literature 2 also, the cover part configured to embracingly retain the knob is disposed on the outer side of the plug. Thus, Patent Literature 2 is not applicable to densely disposed adapters. 
     BRIEF SUMMARY 
     An object of the present invention is to provide a tool for a plug, a slider, a plug, and a cable with a plug which contribute to implementing a compact device which supports densely disposed adapters. 
     An aspect of the present invention is a tool for a plug including a plug body fitted to an adapter and a slider supported on the plug body. The tool includes an insertion portion and a handle. The insertion portion is configured to catch the slider. The handle extends in a direction opposite to the insertion portion. The handle includes a fragile part having a locally small cross-sectional area perpendicular to the direction in which the handle extends. 
     Another aspect of the present invention is a slider supported on a plug body configured to be fitted to an adapter. The slider includes a handle extending integrally from the slider in a direction opposite to the plug body. The handle includes a fragile part having a locally small cross-sectional area perpendicular to the direction in which the handle extends. 
     The present invention provides a tool for a plug, a slider, a plug, and a cable with a plug which contribute to implementing a compact device which supports densely disposed adapters. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a perspective view of a cable with a plug according to a first embodiment. 
         FIG.  2    is an exploded perspective view of the plug. 
         FIG.  3    is a rear view of a slider. 
         FIG.  4 A  is a cross-sectional view showing an operation of the parts of the plug in removing the plug from the adapter. 
         FIG.  4 B  is a cross-sectional view showing an operation of the parts of the plug in removing the plug from the adapter. 
         FIG.  4 C  is a cross-sectional view showing an operation of the parts of the plug in removing the plug from the adapter. 
         FIG.  5 A  is a side view of a tool for a plug. 
         FIG.  5 B  is a plan view of the tool for a plug. 
         FIG.  5 C  is a rear view of the tool for a plug. 
         FIG.  6 A  is a cross-sectional view showing an operation of the parts of the plug in fitting the adapter and the plug to each other using the tool for a plug. 
         FIG.  6 B  is a cross-sectional view showing an operation of the parts of the plug in fitting the adapter and the plug to each other using the tool for a plug. 
         FIG.  6 C  is a cross-sectional view showing an operation of the parts of the plug in fitting the adapter and the plug to each other using the tool for a plug. 
         FIG.  7 A  is a cross-sectional view showing an operation of the parts of the plug in removing the plug from the adapter using the tool for a plug. 
         FIG.  7 B  is a cross-sectional view showing an operation of the parts of the plug in removing the plug from the adapter using the tool for a plug. 
         FIG.  7 C  is a cross-sectional view showing an operation of the parts of the plug in removing the plug from the adapter using the tool for a plug. 
         FIG.  8    is a schematic illustration for describing the operation of the tool for a plug shown in  FIGS.  5 A to  5 C . 
         FIG.  9 A  is a cross-sectional view showing an operation of the parts of the plug in removing the tool for a plug. 
         FIG.  9 B  is a cross-sectional view showing an operation of the parts of the plug in removing the tool for a plug. 
         FIG.  9 C  is a cross-sectional view showing an operation of the parts of the plug in removing the tool for a plug. 
         FIG.  10    is an enlarged view of a portion encircled by broken-line circle X in  FIG.  7 A . 
         FIG.  11    is an enlarged view of a portion encircled by broken-line circle XI in  FIG.  9 B . 
         FIG.  12 A  is a side view of a tool for a plug according to a second embodiment. 
         FIG.  12 B  is a plan view of the tool for a plug according to the second embodiment. 
         FIG.  12 C  is a rear view of the tool for a plug according to the second embodiment. 
         FIG.  13    is a schematic illustration for describing the operation of the tool for a plug shown in  FIGS.  12 A to  12 C . 
     
    
    
     DETAILED DESCRIPTION 
     First Embodiment 
     In the following, with reference to the drawings, a description will be given of a first embodiment. 
     As shown in  FIG.  1   , a plug  2  is attached to a terminal part of an optical fiber cable  1 . The plug  2  is fitted to an adapter  5  provided at a panel  4  of a device  3 . The device  3  is, for example, a communication device or a plugboard. The optical fiber cable  1  is connected to, for example, an optical module installed in the communication device, or other optical fiber cable housed in the plugboard via an adapter  5 . 
     The adapter  5  includes an adapter so-called receptacle of which fitting holes are provided just on the front side of the panel  4 , and an adapter of which the fitting holes are provided at a front side and a back side of the panel  4 . The adapter  5  of which the fitting holes are provided just on the front side of the panel  4  is representatively used in connecting between the optical fiber cable  1  and an optical module. The adapter  5  having fitting holes provided on both the front side and the back side of the panel  4  is representatively used in connecting between the optical fiber cable  1  and other optical fiber cable. 
       FIGS.  2  and  3    show the structure of the plug  2 . 
     The plug  2  includes a plug body  10 , a slider  11 , and a tool  12 . 
     The plug body  10  includes ferrules  20 , plug frames  21 , and a latch frame  22 . Each ferrule  20  retains the terminal part of the optical fibers of the optical fiber cable  1 . The plug frame  21  supports the ferrule  20 . The latch frame  22  supports the plug frame  21 . 
     The optical fiber cable  1  may be a single optical fiber cable, or may be a multi optical fiber cable including two or more optical fibers. The ferrule  20  according to the present embodiment is provided for each optical fiber. The number of the ferrule  20  is changed as appropriate according to the number of optical fibers of the optical fiber cable  1 . Note that, each ferrule  20  may be a multi optical fiber ferrule configured to retain a plurality of optical fibers. 
     The latch frame  22  has a sleeve-like shape. The optical fiber cable  1  is inserted into the latch frame  22 , and drawn out from an opening on the one axial end (first end) of the latch frame  22 . The basal end of the optical fiber cable  1  drawn out from the latch frame  22  is covered with a boot  23  for preventing the cable from bending. The boot  23  is tapered from the basal end on the latch frame  22  side toward the other end. 
     The plug frame  21  is inserted into the latch frame  22  from the opening on the other axial end (second end) side of the latch frame  22 , and removably caught by the latch frame  22 . The tip of the plug frame  21  covering the ferrule  20  is disposed so as to project from the opening on the other axial end (second end) side of the latch frame  22 . The tip of the plug frame  21  is fitted to the adapter  5 . Hereinafter, the direction in which the plug frame  21  projects from the latch frame  22  is defined as the front side in the plug  2 , and the opposite direction is defined as the rear side. By the plug body  10  being pulled rearward, the plug frame  21  is pulled out from the adapter  5 . 
     On one surface (outer surface)  22   a  of the outer circumference of the latch frame  22 , latches  25  configured to be caught by the adapter  5  are provided. Hereinafter, in the plane of the outer surface  22   a , the direction perpendicular to the front-rear direction and parallel to the outer surface  22   a  is defined as the width direction in the plug  2 . The direction perpendicular to the outer surface  22   a  is defined as the top-bottom direction in the plug  2 , and the outer surface  22   a  side is defined as the upper side. Note that, while two latches  25  are disposed so as to be spaced apart from each other in the width direction, at least one latch  25  will suffice. 
     Each latch  25  extends frontward from a support part  26  fixed to the outer surface  22   a  of the latch frame  22 . The front end  27  of the latch  25  is disposed above the plug frame  21 . The latch  25  and the outer surface  22   a  of the latch frame  22  and the outer surface  21   a  of the plug frame  21  are spaced apart from each other, except for at the support part  26 . The elastically bent latch  25  allows the front end  27  to displace from the position above the outer surface  21   a  of the plug frame  21  toward the outer surface  21   a . The front end  27  is accommodated together with the plug frame  21  in the adapter  5 . The front end  27  is provided with a catch projection  28  configured to be caught by the adapter  5 . 
     The slider  11  includes a cover part  30  and a grip part  31 . The cover part  30  is disposed above the latch  25 . The grip part  31  is disposed behind the latch frame  22 . The outer surface  22   a  of the latch frame  22  and the cover part  30  oppose to each other having the latch  25  interposed between them. The outer surface  22   a  of the latch frame  22  is provided with an engaging part  40 . The cover part  30  is provided with an engaging part  41  configured to engage with the engaging part  40 . The engaging parts  40 ,  41  support the slider  11  so as to be slidably rearward, in other words, so as to be shiftable in the removal direction in which the plug frame  21  is pulled out from the adapter  5 . 
     The engaging part  40  includes a rib  42  and a pair of wings  43 . The rib  42  is fixed to the outer surface  22   a  of the latch frame  22 . The wings  43  project on the opposite sides in the width direction from the upper end of the rib  42 . The engaging part  40  has a substantially T-shaped cross-sectional shape as a whole, and extends in the front-rear direction. 
     As shown in  FIG.  3   , the engaging part  41  of the cover part  30  includes a pair of arms  44 , which arms  44  are spaced apart from each other in the width direction. The pair of arms  44  has the rib  42  and the pair of wings  43  interposed in the width direction. By the engagement between the rib  42  and the pair of wings  43  and the pair of arms  44 , the cover part  30  is guided in the front-rear direction. Each arm  44  is provided with an engaging tab  45  which is accommodated between the outer surface  22   a  of the latch frame  22  and corresponding wing  43 . The engagement between the wings  43  and the engaging tabs  45  restricts loosening of the cover part  30 . Thus, the slider  11  is supported so as to be shiftable in the removal direction. Note that, the grip part  31  of the slider  11  disposed behind the latch frame  22  is provided with an insert hole  32  into which the boot  23  is inserted. The engagement between the inner circumference of the insert hole  32  and the boot  23  contributes to the supporting the slider  11 . 
     The engaging part  41  includes a stopper  46  configured to fill up the space between respective front ends of the arms  44 . The movable range in the removal direction of the slider  11  is defined by the stopper  46  and the grip part  31 . When the slider  11  shifts in the removal direction by a predetermined amount, the stopper  46  abuts on the front edge of the rib  42 , to prevent shifting of the slider  11  in the removal direction. When the slider  11  shifts by a predetermined amount in the direction opposite to the removal direction, the grip part  31  abuts on the rear edge of the latch frame  22 , to prevent shifting of the slider  11  in the direction opposite to the removal direction. 
     Note that, the structure of the engaging part  40  and the engaging part  41  is not limited to that described above. For example, the engaging part  41  of the cover part  30  may have the rib  42  and the pair of wings  43 , and the engaging part  40  of the latch frame  22  may have the pair of arms  44 . 
     The slider  11  includes push-down parts  33  configured to push down the latches  25  according to shifting in the removal direction. The push-down parts  33  are provided at the cover part  30 . Between the outer surface  22   a  of the latch frame  22  and the cover part  30 , the latches  25  are interposed. Each latch  25  includes a slide surface  25   a  which is inclined so as to be increasingly spaced apart from the outer surface  22   a  in the removal direction. When the slider  11  shifts in the removal direction, each push-down part  33  slides along the slide surface  25   a  in the removal direction, to push down corresponding latch  25  toward the outer surface  22   a . The pushed down latch  25  elastically bents, and the front end  27  is displaced toward the outer surface  21   a  of the plug frame  21 . 
       FIGS.  4 A to  4 C  each show an operation of the parts of the plug  2  in canceling fitting between the adapter  5  and the plug body  10 . 
     As shown in  FIG.  4 A , the plug frame  21  is fitted to the adapter  5 . The front end  27  of each latch  25  is also accommodated in the adapter  5 . The catch projection  28  provided at the front end  27  is caught by a catch part  6  of the adapter  5 . 
     As shown in  FIG.  4 B , when the slider  11  is pulled in the removal direction, the slider  11  shifts in the removal direction relative to the plug body  10  fixed to the adapter  5 . Then, each push-down part  33  of the slider  11  slides along the slide surface  25   a  of corresponding latch  25 , to push down the latch  25 . The pushed down latch  25  elastically bents, and the front end  27  is displaced toward the outer surface  21   a  of the plug frame  21 . In accordance with the displacement of the front end  27 , the engagement between the catch part  6  and the catch projection  28  is canceled, allowing the fitting between the adapter  5  and the plug frame  21  to be canceled. 
     As shown in  FIG.  4 C , when the slider  11  is continuously pulled in the removal direction, the slider  11  reaches one end in the removal direction in the movable range. Then, the plug body  10  also is pulled in the removal direction integrally with the slider  11 , whereby the engagement between the adapter  5  and the plug frame  21  is canceled. Thus, the plug frame  21  is pulled out from the adapter  5 . 
     In this manner, by the slider  11  shifting in the removal direction, the fitting between the adapter  5  and the plug frame  21  is canceled, and the plug frame  21  is pulled out from the adapter  5 . 
     The tool  12  is used for pulling the slider  11  in the removal direction, thereby removing the plug body  10  from the adapter  5 . For example, as shown in  FIG.  1   , in the case where a plurality of adapters  5  are densely disposed at the panel  4  of the device  3  and a plurality of optical fiber cables  1  connected to the device  3  are also densely disposed and therefore it is difficult for the user to manipulate any slider  11 , the tool  12  is attached to the slider  11 . The slider  11  is pulled in the removal direction via the tool  12 . The tool  12  according to the present embodiment is used also for fitting the adapter  5  to the plug body  10 . 
     As shown in  FIGS.  2  and  3   , the grip part  31  of the slider  11  includes a slot  50  into which the tool  12  is inserted. The slot  50  opens at the rear surface of the grip part  31 . The tool  12  is inserted into the slot  50  in the direction opposite to the removal direction. The slot  50  includes a catch part  51  which is caught by the inserted tool  12 . 
     The slot  50  is continuous to a gap between the latch frame  22  of the plug body  10  and the cover part  30  of the slider  11 . At the outer surface  22   a  of the latch frame  22 , a pressed part  52  configured to abut on the tool  12  inserted into the slot  50  is provided. While the structure of the pressed part  52  is not particularly specified, the pressed part  52  may be a rib which extends in the front-rear direction. 
       FIGS.  5 A to  5 C  each show the structure of the tool  12 . The tool  12  includes an insertion portion  53 , a boot surrounding part  70 , and a handle  71 . The insertion portion  53  is inserted into the slot  50  of the slider  11 . The boot surrounding part  70  is adjacent to the insertion portion  53 . The tool  12  is formed of a resin material. The insertion portion  53 , the boot surrounding part  70 , and the handle  71  are integrally formed. 
     The insertion portion  53  includes a taper part  55  and a basal part  56 . The taper part  55  has its thickness gradually reduced toward the tip of the insertion portion  53 . The basal part  56  is provided adjacent to the taper part  55  on the boot surrounding part  70  side. The taper part  55  includes an inclined surface  55   a  on a first surface  53   a  side, which first surface  53   a  is one of surfaces on the opposite sides of the insertion portion  53  in the thickness direction. The inclined surface  55   a  is inclined relative to a second surface  53   b , which is the other surface. The basal part  56  has a constant thickness. The basal part  56  includes, on the first surface  53   a  side of the insertion portion  53 , a surface  56   a  which is parallel to the second surface  53   b . The insertion portion  53  is inserted into the slot  50  having the second surface  53   b  oriented upward in the plug  2 . 
     The insertion portion  53  includes a catch projection  57 , a pressing projection  58 , and a pressing part  59 . The catch projection  57  catches the catch part  51  of the slider  11 . The pressing projection  58  presses the catch part  51 . The pressing part  59  abuts on the pressed part  52  of the plug body  10 . 
     The catch projection  57  is provided in the outer circumferential surface of the insertion portion  53  (the first surface  53   a , the second surface  53   b , and side surfaces  53   c ,  53   d  on the opposite sides in the width direction) excluding the first surface  53   a  where the inclined surface  55   a  of the taper part  55  is provided. The catch projection  57  according to the present embodiment is provided at the second surface  53   b.    
     As shown in  FIG.  2   , the catch part  51  of the slider  11  is provided at, out of four walls surrounding the slot  50 , the upper wall  60  which opposes to the second surface  53   b  of the insertion portion  53  inserted into the slot  50 . The catch part  51  according to the present embodiment includes a through hole  61  and an inner wall  62 . The through hole  61  is formed at the upper wall  60 . The inner wall  62  is formed on the slot opening side of the through hole  61 . The catch projection  57  is accommodated in the through hole  61 , and caught by the inner wall  62 . 
     A front surface  57   a  of the catch projection  57  positioned on the tip side of the insertion portion  53  abuts on the catch part  51  when the insertion portion  53  is inserted into the slot  50 . The front surface  57   a  is an inclined surface inclined toward the handle  54  relative to the direction perpendicular to the second surface  53   b  of the insertion portion  53 . When the insertion portion  53  is inserted into the slot  50 , the catch part  51  passes over the catch projection  57 . By virtue of the front surface  57   a  being an inclined surface, the catch part  51  smoothly passes over the catch projection  57 , and the inserting the insertion portion  53  into the slot  50  is facilitated. 
     In the state where the insertion portion  53  is inserted into the slot  50 , a rear surface  57   b  on the side opposite to the front surface  57   a  engages with the inner wall  62  of the catch part  51 . The rear surface  57   b  is substantially perpendicular to the second surface  53   b . The rear surface  57   b  may be disposed on the taper part  55  of the insertion portion  53 . The rear surface  57   b  according to the present embodiment is disposed on the basal part  56 . 
     The pressing projection  58  is provided at the second surface  53   b  of the insertion portion  53  on the handle  54  side than the catch projection  57  is. A height H 2  from the second surface  53   b  of the pressing projection  58  is smaller than a height H 1  of the catch projection  57 . In the state where the insertion portion  53  is inserted into the slot  50 , the pressing projection  58  is in contact with the catch part  51 , or disposed below the catch part  51  having a slight clearance set between the pressing projection  58  and the catch part  51 . 
     The pressing part  59  is provided at the tip of the insertion portion  53 . When the insertion portion  53  is inserted into the slot  50 , the pressing part  59  abuts on the pressed part  52  of the plug body  10 . The pressing part  59  may be the tip surface of the insertion portion  53 . The pressing part  59  is formed as a recess capable of accommodating the pressed part  52 . Therefore, the pressing part  59  accommodates the pressed part  52  and also functions as a guide for the insertion portion  53  being inserted into the slot  50 . 
     The boot surrounding part  70  has a sleeve-like shape into which the optical fiber cable  1  and the boot  23  can be inserted. The boot surrounding part  70  includes a slit  72  which extends over the entire length in the axial direction. A width W of the slit  72  is greater than the diameter of the optical fiber cable  1 , and smaller than the maximum diameter (the outer diameter of the basal end) of the boot  23 . An arbitrary portion of the optical fiber cable  1  excluding the basal end covered with the boot  23  is capable of entering the boot surrounding part  70  through the slit  72 , and capable of leaving the boot surrounding part  70  through the slit  72 . The boot  23  cannot pass through the slit  72 . Accordingly, the boot  23  and the boot surrounding part  70  accommodating the boot  23  restrain each other in the diameter direction of the boot  23 . 
     The outer circumference of the boot surrounding part  70  in the cross section perpendicular to the axial direction has a quadrangular shape. A handle  71  is provided at a pair of side surfaces of the boot surrounding part  70 . As shown in  FIG.  5 B , a recessed surface is provided at the axial central part in each side surface of the boot surrounding part  70 . The recessed surfaces form the handle  71 . 
     As shown in  FIG.  5 C , when the tool  12  is seen from the removal direction, the boot surrounding part  70  is positioned inner than an outermost shape line OL of the plug  2 . The outermost shape line OL of the plug  2  is, when the plug  2  without the tool  12  is parallel-projected so that the projection line is perpendicular to the projection plane, the contour line of the projection of the plug  2  on the projection plane. 
     The tool  12  is attached to the plug  2  as follows. Firstly, a portion of the optical fiber cable  1  excluding the basal end covered with the boot  23  is accommodated in the boot surrounding part  70  through the slit  72 . Then, the tool  12  accommodating the optical fiber cable  1  in the boot surrounding part  70  is shifted toward the basal end side of the optical fiber cable  1  along the optical fiber cable  1 , to accommodate the boot  23  in the boot surrounding part  70 . The insertion portion  53  is inserted into the slot  50  of the slider  11 , so that the catch projection  57  catches the catch part  51  of the slider  11 . 
       FIGS.  6 A to  6 C  each show an operation of the parts of the plug  2  in fitting the adapter  5  and the plug  2  to each other using the tool  12 . As shown in  FIG.  6 A , the insertion portion  53  of the tool  12  is inserted into the slot  50  of the slider  11 . The pressing part  59  of the insertion portion  53  abuts on the pressed part  52  of the plug body  10 . 
     As shown in  FIG.  6 B , the handle  71  of the tool  12  is pressed in the fitting direction in which the plug body  10  is fitted to the adapter  5 . Then, via the pressing part  59  and the pressed part  52 , the plug body  10  also is pressed, to shift the plug body  10  in the fitting direction. In accordance with the shifting of the plug body  10 , the plug frame  21  of the plug body  10  and the front end  27  of each latch  25  are inserted into the adapter  5 . 
     As shown in  FIG.  6 C , until the adapter  5  and the plug frame  21  fit to each other, the plug body  10  shifts in the fitting direction. Then, the catch part  6  of the adapter  5  passes over the catch projection  28  of the latch  25 , and the catch projection  28  is caught by the catch part  6 . 
     Note that, the tool  12  may press the slider  11  in place of the plug body  10 . For example, by causing the end surface of the boot surrounding part  70  on the slider side to abut on the rear end surface of the slider  11 , the slider  11  can be pressed. Note that, preferably, the tool  12  directly presses the plug body  10  fitted to the adapter  5 , because the user feels improved manipulating touch with the tool  12  directly pressing the plug body  10 , as compared to the tool  12  pressing the slider  11  supported on the plug body  10  shiftably in the removal direction and the fitting direction. 
       FIGS.  7 A to  7 C  each show an operation of the parts of the plug  2  in removing the plug  2  from the adapter  5  using the tool  12 . 
     As shown in  FIG.  7 A , the plug frame  21  of the plug body  10  is fitted to the adapter  5 . The front end  27  of each latch  25  is accommodated in the adapter  5 , and the catch projection  28  provided at the front end  27  is caught by the catch part  6  of the adapter  5 . The insertion portion  53  of the tool  12  is inserted into the slot  50  of the slider  11 . The second surface  53   b  of the insertion portion  53  is disposed in parallel to the removal direction of the plug body  10 . Note that, also in the case where the second surface  53   b  is slightly inclined (for example, −5° to +5°) relative to the removal direction, it is regarded that the second surface  53   b  and the removal direction are parallel to each other. 
     As shown in  FIG.  7 B , in the state where the second surface  53   b  of the insertion portion  53  is disposed in parallel to the removal direction of the plug body  10 , the handle  71  of the tool  12  is pulled in the removal direction of the plug body  10 . Then, the catch projection  57  of the insertion portion  53  catches the catch part  51  of the slider  11 , and the slider  11  also is pulled in the removal direction. The slider  11  pulled in the removal direction shifts in the removal direction relative to the plug body  10  fixed to the adapter  5 , and each push-down part  33  of the slider  11  pushes down corresponding latch  25 . The pushed down front end  27  of the latch  25  is displaced toward the outer surface  21   a  of the plug frame  21 . In accordance with the displacement of the front end  27 , the engagement between the catch part  6  of the adapter  5  and the catch projection  28  provided at the front end  27  is canceled, allowing the fitting between the adapter  5  and the plug frame  21  to be canceled. 
     As shown in  FIG.  7 C , as the tool  12  is continuously pulled in the removal direction, the slider  11  reaches one end in the removal direction in the movable range. Subsequently, integrally with the slider  11 , the plug body  10  also is pulled in the removal direction. Thus, the fitting between the adapter  5  and the plug frame  21  is canceled, and the plug frame  21  is pulled out from the adapter  5 . 
       FIG.  8    schematically shows the operation of the tool  12 . In the example shown in  FIG.  8   , to part of a plurality of adapters  5  provided at the panel  4  of the device  3 , the plugs  2  are already fitted. The adapters  5  are densely disposed, and there exists just a slight clearance between adjacent two pieces of plugs  2  fitted to the adapters  5 . In this state, a plug  2  is fitted to a free adapter  5 . Hereinafter, the plugs  2  already fitted to the adapter  5  are referred to as the plugs  2   a  and the plug  2  to be fitted to the free adapter  5  is referred to as the plug  2   b , to be distinguished from each other. 
     To the plug  2   b , the tool  12  is attached. The boot surrounding part  70  of the tool  12  accommodates the boot  23 , and restrains the boot  23  in the diameter direction. The insertion portion  53  of the tool  12  is inserted into the slot  50  of the slider  11 , to catch the slider  11 . Thus, the plug  2   b  is retained on the tool  12  without coming off frontward. This improves workability in fitting the plug  2   b  to the adapter  5 . 
     As shown in  FIG.  5 C , the boot surrounding part  70  of the tool  12  is positioned inner than the outermost shape line OL of the plug  2 . Accordingly, the clearance between the tool  12  attached to the plug  2   b  and the tools  12  attached to the plugs  2   a  around the plug  2   b  is wider than the clearance between the plug  2   b  and the surrounding plugs  2   a . This allows the user to surely grip the handle  71  of the tool  12  attached to the plug  2   b  and facilitates the user&#39;s manipulating the tool  12 . In particular, in the present embodiment, since the handle  71  is formed in a recessed manner at the side surfaces of the boot surrounding part  70 , the clearance around the handle  71  is increasingly widened. 
     The boot  23  and the boot surrounding part  70  accommodating the boot  23  restrain each other in the diameter direction of the boot  23 . This minimizes any tilting of the tool  12  relative to the plug  2   b . Thus, the force applied to the tool  12  is fully used in fitting the plug  2   b  and the adapter  5  to each other. This also minimizes the risk of breakage of the insertion portion  53  and the slot  50  that may otherwise be done by excessively tilted tool  12 . 
     While the foregoing is the operation of the tool  12  is the operation in fitting the plug  2   b  and the adapter  5  to each other, this similarly applies to the operation in removing the plug  2   b  from the adapter  5 . That is, the user is allowed to surely grip the handle  71  of the tool  12  attached to the plug  2   b , to manipulate the tool  12  and easily pull out the plug  2   b  from the adapter  5 . The force applied to the tool  12  is fully used in pulling out the plug  2   b . This also minimizes the risk of breakage of the insertion portion  53  and the slot  50  that may otherwise be done by excessively tilted tool  12 . 
     The length of the boot surrounding part  70  may be set as appropriate in view of workability. The length of the boot surrounding part  70  may be greater than, shorter than, or equal to the length of the boot  23 . 
     The tool  12  attached to the plug  2  is pulled out from the plug  2  in the state where the plug  2  is pulled out from the adapter  5 .  FIGS.  9 A to  9 C  each show an operation of the parts of the plug  2  in removing the tool  12 . 
     As shown in  FIG.  9 A , the insertion portion  53  of the tool  12  is inserted into the slot  50  of the slider  11 . In removing the tool  12  from the plug  2 , firstly, the plug frame  21  of the plug body  10  is pulled out frontward from the latch frame  22 . In accordance with the plug frame  21  being pulled out, the optical fiber cable  1  and the boot  23  are pulled into the latch frame  22 , and the boot surrounding part  70  of the tool  12  accommodates a portion of the optical fiber cable  1  except for the basal end covered with the boot  23 . The width W of the slit  72  of the boot surrounding part  70  (see  FIG.  5 C ) is greater than the outer diameter of the optical fiber cable  1 , and the portion of the optical fiber cable  1  accommodated in the boot surrounding part  70  is capable of leaving the boot surrounding part  70  through the slit  72 . Accordingly, the restrain of the boot surrounding part  70  is canceled, and the tool  12  is allowed to be inclined relative to the plug  2 . 
     As shown in  FIG.  9 B , the boot surrounding part  70  of the tool  12  (the handle  71 ) is shifted, and the tool  12  is inclined relative to the plug  2 . Thus, the inclined surface  55   a  of the taper part  55  is disposed in parallel to the front-rear direction (the fitting or removal direction) of the plug  2 . Note that, in the case where the inclined surface  55   a  is slightly inclined (for example, −5° to +5°) relative to the front-rear direction also, it is regarded that the inclined surface  55   a  and the front-rear direction are parallel to each other. 
     As shown in  FIG.  9 C , in the state where the inclined surface  55   a  of the taper part  55  is disposed in parallel to the front-rear direction of the plug  2 , the tool  12  is pulled rearward from the plug  2 . Thus, the catch projection  57  of the insertion portion  53  cancels the catching between the slider  11  and the catch part  51 , whereby the insertion portion  53  is pulled out from the slot  50  of the slider  11 . Through the foregoing operations, the tool  12  is pulled out from the plug  2 . 
       FIGS.  10  and  11    each show, in detail, the engagement relation between the catch projection  57  of the insertion portion  53  and the catch part  51  of the slider  11 .  FIG.  10    shows the engagement relation in the case where the second surface  53   b  of the insertion portion  53  is disposed in parallel to the front-rear direction of the plug  2 , that is, the case where the insertion portion  53  is inserted into the slot  50  in parallel to the front-rear direction of the plug  2  (the fitting or removal direction).  FIG.  11    shows the engagement relation in the case where the inclined surface  55   a  of the taper part  55  is disposed in parallel to the front-rear direction of the plug  2 , that is, the case where the insertion portion  53  is inserted into the slot  50  as being inclined relative to the front-rear direction of the plug  2 . 
     As shown in  FIG.  10   , in the case where the second surface  53   b  of the insertion portion  53  is disposed in parallel to the front-rear direction of the plug  2 , the rear surface  57   b  of the catch projection  57  is substantially perpendicular to the second surface  53   b . Accordingly, the rear surface  57   b  and the inner wall  62  of the catch part  51  face each other in the front-rear direction of the plug  2 . In this case, when the tool  12  is pulled rearward from the plug  2 , the catch projection  57  catches the catch part  51 , and the slider  11  is pulled rearward integrally with the tool  12  (see  FIGS.  7 B to  7 C ). 
     On the other hand, as shown in  FIG.  11   , in the case where the inclined surface  55   a  of the taper part  55  is disposed in parallel to the front-rear direction of the plug  2 , the rear surface  57   b  of the catch projection  57  falls on the side opposite to the inner wall  62  of the catch part  51 . Accordingly, as compared to the case where the rear surface  57   b  and the inner wall  62  face each other in the front-rear direction of the plug  2 , the engaging force between them is weak. In this case, when the tool  12  is pulled rearward from the plug  2 , the catch part  51  easily passes over the catch projection  57 , and the catch projection  57  cancels the catching of the catch part  51 . Thus, the tool  12  is pulled out from the plug  2  (see  FIGS.  9 B to  9 C ). 
     The insertion portion  53  according to the present embodiment includes the pressing projection  58 . In the state where the insertion portion  53  is inserted into the slot  50 , the pressing projection  58  is in contact with the catch part  51  or disposed beneath the catch part  51  as being slightly spaced apart from the catch part  51 . As shown in  FIG.  11   , when the inclined surface  55   a  of the taper part  55  is disposed in parallel to the front-rear direction of the plug  2 , the catch part  51  is pushed upward by the pressing projection  58  while elastically bending. Thus, an engagement margin Lap 2  between the rear surface  57   b  of the catch projection  57  and the inner wall  62  becomes smaller than an engagement margin Lap 1  in the case where the second surface  53   b  of the insertion portion  53  is disposed in parallel to the front-rear direction of the plug  2 . This further weakens the engagement force between the rear surface  57   b  and the inner wall  62 , and the tool  12  is easily pulled out from the plug  2 . 
     Second Embodiment 
       FIGS.  12 A to  12 C  each show a tool for a plug according to a second embodiment which is applicable to the plug  2  described above. 
     The tool  112  includes an insertion portion  153 , a boot surrounding part  170 , and a handle  171 . The insertion portion  153  is inserted into the slot  50  of the slider  11 . The boot surrounding part  170  is adjacent to the insertion portion  153 . The tool  112  is formed of a resin material. The insertion portion  153 , the boot surrounding part  170 , and the handle  171  are integrally formed. Note that, the insertion portion  153  is identical to the insertion portion  53  of the tool  12  according to the first embodiment. The description of the structure of the insertion portion  53  is incorporated herein by reference, to simplify or omit the description of the insertion portion  153 . 
     The boot surrounding part  170  has a sleeve-like shape into which the optical fiber cable  1  and the boot  23  can be inserted. The boot surrounding part  170  includes a slit  172  which extends over the entire length in the axial direction. A width W 1  of the slit  172  is greater than the diameter of the optical fiber cable  1 , and smaller than the maximum diameter (the outer diameter of the basal end) of the boot  23 . An arbitrary portion of the optical fiber cable  1  excluding the basal end covered with the boot  23  is capable of entering the boot surrounding part  170  through the slit  172 , and capable of leaving the boot surrounding part  170  through the slit  172 . On the other hand, the boot  23  cannot pass through the slit  172 . Accordingly, the boot  23  and the boot surrounding part  170  accommodating the boot  23  restrain each other in the diameter direction of the boot  23 . 
     The handle  171  has a rod-like shape. The handle  171  extends from the boot surrounding part  170  in the axial direction of the boot surrounding part  170  on the side opposite to the insertion portion  153 . A width W 2  of the handle  171  is smaller than a width W 3  of the boot surrounding part  170 . At the tip of the handle  171 , a first grip part  173  is provided. The first grip part  173  includes a pair of convex parts  173   a ,  173   b , which convex parts  173   a ,  173   b  project on the opposite sides in the width direction. Between the end of the boot surrounding part  170  on the handle side and the first grip part  173 , a fragile part  174  is provided. Between the end of the boot surrounding part  170  on the handle side and the fragile part  174 , a second grip part  175  is provided. 
     The fragile part  174  includes a through hole  176  which penetrates through the handle  171  in the thickness direction. Thus, the cross-sectional area of the parts of the handle  171  in the longitudinal direction is locally small at the fragile part  174 . That is, the fragile part  174  is relatively fragile. Note that, the cross-sectional area of the fragile part  174  should just be locally small. The fragile part  174  may include a recessed part or a groove in place of the through hole  176 . 
     Similarly to the first grip part  173 , the second grip part  175  includes a pair of convex parts  175   a ,  175   b , which convex parts  175   a ,  175   b  project on the opposite sides in the width direction. Preferably, the convex parts  175   a ,  175   b  project on the opposite sides in the thickness direction, having a portion of the fragile part  174  interposed between them. When the fragile part  174  is broken, the tip of the handle  171  is implemented by the second grip part  175 . The edge resulting from the breakage of the fragile part  174  is housed in the pair of convex parts  175   a ,  175   b . This avoids contact between the edge resulting from the breakage and the optical fiber cable  1 , thereby minimizing the risk of breakage of the optical fiber cable  1  that may otherwise be done by such a contact with the edge. 
     As shown in  FIG.  12 C , when the tool  112  is seen from the removal direction, the boot surrounding part  170  of the tool  112  is positioned inner than the outermost shape line OL of the plug  2 . As used herein, the outermost shape line OL of the plug  2  is, when the plug  2  without the tool  112  is parallel-projected so that the projection line is perpendicular to the projection plane, the contour line of the projection of the plug  2  on the projection plane. 
     The tool  112  is attached to the plug  2  as follows. Firstly, a portion of the optical fiber cable  1  excluding the basal end covered with the boot  23  is accommodated in the boot surrounding part  170  through the slit  172 . Then, the tool  112  accommodating the optical fiber cable  1  in the boot surrounding part  170  is shifted toward the basal end side of the optical fiber cable  1  along the optical fiber cable  1  so that the boot surrounding part  170  accommodates the boot  23 . The insertion portion  153  is inserted into the slot  50  of the slider  11 , so that the catch projection  157  catches the catch part  51  of the slider  11 . 
     In fitting the adapter  5  and the plug  2  to each other using the tool  112 , the insertion portion  153  of the tool  112  is inserted into the slot  50  of the slider  11 . In the state where the pressing part  159  of the insertion portion  153  abuts on the pressed part  52  of the plug body  10 , the handle  171  of the tool  112  is pressed in the fitting direction. The plug frame  21  of the plug body  10  and the front end  27  of each latch  25  are inserted into the adapter  5 , and the plug body  10  shifts in the fitting direction until the adapter  5  and the plug frame  21  fit to each other. Then, the catch part  6  of the adapter  5  passes over the catch projection  28  of the latch  25 , and the catch projection  28  is caught by the catch part  6  (see  FIGS.  6 A to  6 C ). 
     In removing the plug  2  from the adapter  5  using the tool  112 , the insertion portion  153  of the tool  112  is inserted into the slot  50  of the slider  11 . In the state where the second surface  153   b  of the insertion portion  153  is disposed in parallel to the removal direction of the plug body  10 , the handle  171  of the tool  112  is pulled in the removal direction of the plug body  10 . The catch projection  57  of the insertion portion  53  catches the catch part  51  of the slider  11 , and the slider  11  also is pulled in the removal direction. The slider  11  pulled in the removal direction shifts in the removal direction relative to the plug body  10  fixed to the adapter  5 , and each push-down part  33  of the slider  11  pushes down corresponding latch  25 . The pushed down front end  27  of the latch  25  is displaced toward the outer surface  21   a  of the plug frame  21 . In accordance with the displacement of the front end  27 , the engagement between the catch part  6  of the adapter  5  and the catch projection  28  provided at the front end  27  is canceled, allowing the fitting between the adapter  5  and the plug frame  21  to be canceled. As the tool  112  is continuously pulled in the removal direction, the slider  11  reaches one end in the removal direction in the movable range. Subsequently, integrally with the slider  11 , the plug body  10  also is pulled in the removal direction. Thus, the fitting between the adapter  5  and the plug frame  21  is canceled, and the plug frame  21  is pulled out from the adapter  5 . 
       FIG.  13    schematically shows the operation of the tool  112 . In the example shown in  FIG.  13   , to a part of a plurality of adapters  5  provided at the panel  4  of the device  3 , the plugs  2  are already fitted. The adapters  5  are densely disposed, and there exists just a slight clearance between adjacent two pieces of plugs  2  fitted to the adapters  5 . In this state, a plug  2  is fitted to a free adapter  5 . Hereinafter, the plugs  2  already fitted to the adapters  5  are referred to as the plugs  2   a , and the plug  2  to be fitted to the free adapter  5  is referred as the plug  2   b , to be distinguished from each other. 
     To the plug  2   b , the tool  112  is attached. The boot surrounding part  170  of the tool  112  accommodates the boot  23 , and restrains the boot  23  in the diameter direction. The insertion portion  153  of the tool  112  is inserted into the slot  50  of the slider  11 , to catch the slider  11 . Thus, the plug  2   b  is retained on the tool  112  without coming off frontward. This improves workability in fitting the plug  2   b  to the adapter  5 . 
     As shown in  FIG.  12 C , the boot surrounding part  170  of the tool  112  is positioned inner than the outermost shape line OL of the plug  2 . Accordingly, the clearance between the tool  112  attached to the plug  2   b  and the tools  112  attached to the plugs  2   a  around the plug  2   b  is wider than the clearance between the plug  2   b  and the surrounding plugs  2   a . In particular, the width W 2  of the handle  171  is smaller than the width W 3  of the boot surrounding part  170 , and the clearance around the handle  171  is wider than the clearance around the boot surrounding part  170 . This allows the user to surely grip the handle  171  of the tool  112  attached to the plug  2   b  and facilitates the user&#39;s manipulating the tool  112 . 
     The boot  23  and the boot surrounding part  170  accommodating the boot  23  restrain each other in the diameter direction of the boot  23 . This minimizes any tilting of the tool  112  relative to the plug  2   b . Thus, the force applied to the tool  112  is fully used in fitting the plug  2   b  and the adapter  5  to each other. This also minimizes the risk of breakage of the insertion portion  53  and the slot  50  that may otherwise be done by excessively tilted tool  112 . 
     While the foregoing is the operation of the tool  112  is the operation in fitting the plug  2   b  and the adapter  5  to each other, this similarly applies to the operation in removing the plug  2   b  from the adapter  5 . That is, the user is allowed to surely grip the handle  171  of the tool  112  attached to the plug  2   b , to manipulate the tool  112  and easily pull out the plug  2   b  from the adapter  5 . The force applied to the tool  112  is fully used in pulling out the plug  2   b . This also minimizes the risk of breakage of the insertion portion  53  and the slot  50  that may otherwise be done by excessively tilted tool  112 . 
     By the fragile part  174  of the handle  171  broken in the state where the plug  2   b  is fitted to the adapter  5 , the length of the handle  171  extending in the removal direction from the plug  2   b  is reduced. This facilitates routing the optical fiber cables  1  extending in the removal direction from the plug  2   b  and the surrounding plugs  2   a . After the fragile part  174  is broken, the second grip part  175  remains on the handle  171 . Accordingly, in removing the plug  2   b  from the adapter  5 , the user is allowed to grip the second grip part  175  to easily pull out the plug  2   b  from the adapter  5 . 
     In view of workability in fitting the plug  2  to the adapter  5  and removing from the adapter  5 , a length Ll from the end of the boot surrounding part  170  on the insertion portion side to the tip of the handle  171  is preferably longer than the boot  23 . In view of routing the optical fiber cable  1  in the state where the plug  2  is fitted to the adapter  5 , a length L 2  of the boot surrounding part  170  is preferably shorter than the boot  23 . A length L 3  from the end of the boot surrounding part  170  on the insertion portion side to the tip of the second grip part  175  can be set as appropriate taking into consideration of workability and routing of the optical fiber cable  1 . The length L 3  longer than the boot  23  improves workability; the length L 3  shorter than the boot  23  facilitates routing of the optical fiber cable  1 . 
     The boot surrounding part  170  of the tool  112  according to the present embodiment can be dispensed with. In this case, the handle  171  extends directly from the insertion portion  153  in the axial direction. 
     In the present embodiment, the slider  11  and the tool  112  have been described as separate members. Here, the slider  11  and the tool  112  may be integrated with each other as a single member. In this case, the handle  171  extends directly from the slider  11  in the axial direction. That is, the handle  171  extends oppositely to the plug body  10  and integrally with the slider  11 . 
     In the foregoing, the description has been given of the embodiments of the optical fiber cable  1  and the plug  2  attached to the terminal part. It goes without saying that the embodiments are merely examples, and any change may be made within the scope not deviating from the gist of the present disclosure. For example, the cable may be an electric cable (for example, a LAN (Local Area Network) cable). The cable may be a branch cable including a main line and a plurality of branch lines. When the cable is a branch cable, the terminal part of the cable to which the plug is attached includes the terminal part of the main line and/or the terminal part of each branch line. 
     REFERENCE SIGNS LIST 
     
         
           1  optical fiber cable 
           2  plug 
           5  adapter 
           10  plug body 
           11  slider 
           12  tool 
           50  slot 
           53  insertion portion 
           59  pressing part 
           70  boot surrounding part 
           71  handle 
           72  slit 
           112  tool 
           153  insertion portion 
           159  pressing part 
           170  boot surrounding part 
           171  handle 
           172  slit 
           173  first grip part 
           174  fragile part 
           175  second grip part 
         OL outermost shape line of plug  2