Patent Publication Number: US-2022221654-A1

Title: Optical connector

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Taiwan Patent Application No. 110101410, filed on Jan. 14, 2021, in the Taiwan Intellectual Property Office of the R.O.C, the disclosure of which is incorporated herein in its entirety by reference. 
     FIELD OF INVENTION 
     The present invention relates to an optical connector. In particular, it relates to an optical connector having a coil structure with an elastic coil and a fixing coil to position a coupling terminal to produce shift in the radial direction. 
     BACKGROUND OF THE INVENTION 
     Due to the advantages of high frequency bandwidth and low loss, optical fibers have been widely used as signal transmission media in recent years. The use of optical fiber has already had a major revolutionary impact in the communications industry. Nowadays, 100G optical module communication is not enough, and the future will be expected to move towards the era of 400G optical module communications. 
     In the field of 400G optical communications, there are also many designs for the packaging design of optical fiber modules, one of which is called Quad Small Form Factor Pluggable-Double Density (QSFF-DD). The specification, with a downward compatible design, has attracted the attention of many large manufacturers, and has launched corresponding specifications of optical communication module products. 
       FIG. 1  is a schematic diagram of a conventional optical connector. The optical connector in  FIG. 1  is an LC optical connector. In the prior art, an elastic coil  10  is disposed in the inner space of the optical connector  1 , one end of the elastic coil  10  is leaned against the end surface of the inner housing  11  of the optical connector  1 , and another end is sleeved into the end of the coupling terminal  12 , and leaned against the end surface  13  on the coupling terminal  12 . In the prior art, the entire elastic coil  10  is used as an elastic structure, except for the end being leaned against the inner end surface of the optical connector  1 , and is used to extend or compress to adjust the position of the coupling terminal  12  in the axial direction. In the prior art, because the end of the elastic coil  1  is leaned against the end surface of the internal structure of the optical connector  1 , although it has the positioning effect in the axial direction, there is no proper fixing mechanism in the radial direction perpendicular to the axial direction. In the prior art, because the end of the elastic coil  1  is leaned against the end surface of the internal structure of the optical connector  1 , although it has the positioning effect in the axial direction, there is no proper fixing mechanism in the radial direction perpendicular to the axial direction. As a result, the coupling terminal  12  of the optical connector  1  is prone to lateral displacement due to lateral or radial force when it is coupled to the optical receptacle, thereby affecting the electrical connection effect. In addition, the conventional LC optical connector  1  also has the problem that the length L of the connector body is too long, which limits its application. 
     In summary, it&#39;s necessary for an optical connector to solve the problem of conventional optical connectors. 
     The above information disclosed in this section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. 
     SUMMARY OF THE INVENTION 
     The present invention provides an optical connector, which utilizes elastic elements for fixing the position of the optical connector in the axial and radial directions, so as to prevent the optical connector from a lateral or radial force to cause the displacement of the coupling terminal when the optical connector is inserted into the optical receptacle. The present invention stabilizes the position of the coupling terminal of the optical connector to ensure the effect of signal connection. 
     The present invention provides an optical connector. The coil structure achieves the effect of fixing the elastic coil through a positioning structure arranged inside or outside the housing and integrally formed with the housing. Therefore, it&#39;s not necessary to provide an additional supporting structure for the stop coil structure, thereby shortening the length of the housing, to achieve the effect of saving space. 
     The present invention provides an optical connector, comprising: a housing, having a positioning structure, an accommodation space disposed into the housing; a coupling terminal, disposed into the accommodation space; and a coil structure, having an elastic coil and a first fixing coil, the elastic coil sleeved on the coupling terminal, and the first fixing coil sleeved on the positioning structure. 
     In one embodiment, the positioning structure is disposed into the accommodation space, and has an accommodation groove and a plurality of leaning structures, the accommodation groove is disposed on a wall surface of the accommodation space, the plurality of leaning structures are connected to a wall surface of the housing and correspond to the accommodation groove, and the first fixing coil is disposed into the accommodation groove and restrained by the plurality of leaning structures. 
     In another embodiment, the positioning structure is disposed on an end of the housing, and has an accommodation groove and a leaning structure connected to a side of the accommodation groove, the first fixing coil is disposed into the accommodation groove, and an end section of the first fixing coil is leaned against the positioning structure. 
     Many of the attendant features and advantages of the present invention will become better understood with reference to the following detailed description considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The detailed structure, operating principle and effects of the present invention will now be described in more details hereinafter with reference to the accompanying drawings that show various embodiments of the present invention as follows. 
         FIG. 1  is a schematic diagram of a conventional optical connector. 
         FIG. 2A  is a three-dimensional diagram of an embodiment of the optical connector of the present invention. 
         FIG. 2B  is an exploded schematic diagram of the optical connector of  FIG. 2A . 
         FIG. 2C  is a schematic cross-sectional view of the optical connector of  FIG. 2A . 
         FIG. 3A  is a three-dimensional diagram of another embodiment of the optical connector of the present invention. 
         FIG. 3B  is a schematic cross-sectional view of the optical connector shown in  FIG. 3A . 
         FIG. 3C  is a schematic diagram of connecting the first fixing coil and the housing. 
         FIG. 3D  is a three-dimensional schematic diagram of the coil structure in the optical connector of  FIG. 3A . 
         FIG. 4A  is a three-dimensional exploded schematic view of an embodiment of the optical connector module. 
         FIG. 4B  is a schematic cross-sectional view of an embodiment of an optical connector of the present invention. 
         FIG. 4C  is a schematic diagram of coupling the optical connector and the optical receptacle. 
         FIG. 5A  is an exploded schematic diagram of another embodiment of the optical connector module in the present invention. 
         FIG. 5B  is a schematic cross-sectional view of another embodiment of the optical connector in the present invention. 
         FIG. 6A  is an exploded schematic diagram of another embodiment of the optical connector module of the present invention. 
         FIG. 6B  is a three-dimensional schematic diagram of the optical connector of  FIG. 6A  from different viewing angles. 
         FIG. 6C  is a schematic partial cross-sectional view of the coupling position between the optical connector and the optical receptacle of the present invention. 
         FIG. 6D  is a three-dimensional schematic diagram of the optical connector from different viewing angles in the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Therefore, it is to be understood that the foregoing is illustrative of exemplary embodiments and is not to be construed as limited to the specific embodiments disclosed, and that modifications to the disclosed exemplary embodiments, as well as other exemplary embodiments, are intended to be included within the scope of the appended claims. These embodiments are provided so that this invention will be thorough and complete, and will fully convey the inventive concept to those skilled in the art. The relative proportions and ratios of elements in the drawings may be exaggerated or diminished in size for the sake of clarity and convenience in the drawings, and such arbitrary proportions are only illustrative and not limiting in any way. 
     For convenience, certain terms employed in the specification, examples and appended claims are collected here. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of the ordinary skill in the art to which this invention belongs. 
     Various embodiments will now be described more fully with reference to the accompanying drawings, in which illustrative embodiments are shown. The inventive concept, however, may be embodied in various different forms, and should not be construed as being limited only to the illustrated embodiments. Rather, these embodiments are provided as examples, to convey the inventive concept to one skilled in the art. Accordingly, known processes, elements, and techniques are not described with respect to some of the embodiments. 
     The singular forms “a”, “and”, and “the” are used herein to include plural referents unless the context clearly dictates otherwise. 
     The following descriptions are provided to elucidate a latch structure and optical receptacle thereof and to aid it of skilled in the art in practicing this invention. These embodiments are merely exemplary embodiments and in no way to be considered to limit the scope of the invention in any manner. 
     Please refer to  FIGS. 2A to 2C , in which  FIG. 2A  is a three-dimensional diagram of an embodiment of the optical connector of the present invention,  FIG. 2B  is an exploded schematic diagram of the optical connector of  FIG. 2A , and  FIG. 2C  is a schematic cross-sectional view of the optical connector of  FIG. 2A . In this embodiment, the optical connector  2  includes a housing  20 , a coupling terminal  21  and a coil structure  22 . The housing  20  has a positioning structure  23  and a pressing rod  24 , and the housing  20  has an accommodation space  200 . In this embodiment, the pressing rod  24  located on an outer surface of the housing  20  is used for releasing the coupling state between the optical connector  2  and the connector receptacle, which belongs to the conventional technology and would not be repeated here. In addition, the positioning structure  23  is disposed on the first side A of the accommodation space  200 . The positioning structure  23  further has an accommodation groove  230  and a plurality of leaning structures  231 . The accommodation groove  230  is disposed on the wall surface of the accommodation space  200 , and the plurality of leaning structures  231  are connected to the inner wall surface of the housing  20  and located on a side of the accommodation groove  230  for restraining the coil structure  22  fixed into the accommodation groove  230 . 
     The coupling terminal  21  is disposed into the accommodation space  200 . The coil structure  22  has an elastic coil  220  and a first fixing coil  221 . In this embodiment, the outer diameter of the first fixing coil  221  is larger than the outer diameter of the elastic coil  220 . The elastic coil  220  is sleeved on the coupling terminal  21 , and the elastic coil  220  has a plurality of coils to generate elastic compression and stretching effects. The outermost coil of the elastic coil  220  is leaned against the wall surface of the second side B of the accommodation space  200 . The first fixing coil  221  is sleeved on the positioning structure  23 . In this embodiment, one coil of the first fixing coil  221  is accommodated into the accommodation groove  230  and is restrained by the plurality of leaning structures  231 . It should be noted that, in this embodiment, a second fixing coil  222  is further connected between the elastic coil  220  and the first fixing coil  221 , and sleeved on the coupling terminal  21 . In this embodiment, the first fixing coil  221  and the second fixing coil  222  do not have a compression or stretching spring effect. Moreover, the first fixing coil  221  is a space of the fixing coil structure  22  in the axial direction  90 , the coil structure  22  is avoided being shifted or separated from the housing  20  by the positioning structure  23  in the axial direction  90  and the radial direction  91 , and the second fixing coil  222  is used to fix the coupling terminal  21  to prevent lateral or radial displacement of the coupling terminal  21 . 
     Next, the working principle of the coil structure  22  of this embodiment would be explained. Since the positioning structure  23  restrains the first fixing coil  221 , it may be ensured that when the elastic coil  220  in the coil structure  22  can be stretched and compressed in the central axis  90  of the optical connector  2 , the coil structure  22  would not be separated from the housing  20 . In addition, the second fixing coil  222  is extended and sleeved on the periphery of the coupling terminal  21  by the first fixing coil  221  and does not have the effect of compression or stretching. Therefore, when the coupling terminal  21  is coupled with the optical receptacle, the shift of the coil structure  22  due to the lateral or radial force  91  (shown in  FIG. 2C ) may be avoided, the stability of coupling terminal  21  may be maintained, and the position of the coupling terminal  21  of the optical connector  2  in the axial direction  90  may be stabilized to ensure the effect of signal connection. 
     Please refer to  FIGS. 3A to 3D , in which  FIG. 3A  is a three-dimensional diagram of another embodiment of the optical connector,  FIG. 3A  is a schematic cross-sectional view of the optical connector shown in  FIG. 3A ,  FIG. 3C  is a schematic diagram of connecting the first fixing coil and the housing, and  FIG. 3D  is a three-dimensional schematic diagram of the coil structure in the optical connector of  FIG. 3A . Basically, the optical connector  2   a  is similar to the aforementioned optical connector  2 . The difference is that the positioning structure  23   a  in this embodiment is disposed on the outer wall surface of the housing  20 , and the positioning structure  23   a  further has an accommodation groove  230   a  and a leaning structure  231   a . The leaning structure  231   a  is disposed on one side of the accommodation groove  230   a , and the leaning structure  231   a  has an opening  2300  extending toward the accommodation groove  230   a . The first fixing coil  221   a  of the coil structure  22   a  is located in the accommodation groove  230   a , and the end section  2210  of the first fixing coil  221   a  is bent at a predetermined angle for leaning against the positioning structure  23   a . In this embodiment, the positioning structure  23   a  further has a positioning groove  233   a , which is formed at a side of the opening  2300 , on the wall surface of the accommodation groove  230   a , and leaned against the end section  2210 . A second fixing coil  222   a  is further connected between the elastic coil  220   a  and the first fixing coil  221   a , and is sleeved on the coupling terminal  21 . In this embodiment, the outer diameter of the second fixing coil  222   a  is equal to the outer diameter of the elastic coil  220   a , and is smaller than the outer diameter of the first fixing coil  221   a.    
     When assembling the coil structure  22   a , as shown in  FIGS. 3A and 3B , the end section  2210  of the first fixing coil  221   a  and the extending section  2220  of the second fixing coil  222   a  are compressed toward the central axis of the optical connector  2   a  to allow the first fixing coil  221   a  expand to fit into the accommodation groove  230   a  of the positioning structure  23   a , the end section  2210  is leaned against the leaning structure  231   a  by the elastic pressure, and the positioning effect is generated by an interaction force between the end section  2210  and the positioning groove  233   a . In this embodiment, since the accommodation groove  230   a  restrains the first fixing coil  221   a , it may be ensured that when the elastic coil  220   a  in the coil structure  22   a  is stretched and compressed along the central axis  90  of the optical connector  2   a , the coil structure  22   a  is not separated from the housing. In addition, an end of the coupling terminal  21  would be located between the end section  2210  and the extending section  2220 , and the second fixing coil  222   a  extended by the first fixing coil  221   a  is sleeved on the periphery of the coupling terminal  21 . Therefore, when the coupling terminal  21  is coupled to the optical receptacle, the shift of the coil structure  22   a  due to the lateral or radial force may be avoided, the stability of the coupling terminal  21  is maintained, and the position of the coupling terminal  21  of the optical connector  2  may be stabilized to ensure the effect of signal connection. 
     Please refer to  FIGS. 4A to 4C , in which  FIG. 4A  is a three-dimensional exploded schematic view of an embodiment of the optical connector module,  FIG. 4B  is a schematic cross-sectional view of an embodiment of an optical connector, and  FIG. 4C  is a schematic diagram of coupling the optical connector and the optical receptacle. In this embodiment, the optical connector module  3  includes an optical receptacle  30  and an optical connector  2   b . The optical receptacle  30  is the receptacle of the LC optical connector, but is not limited herein. The optical receptacle  30  includes a receptacle body  300  and a plurality of coupling terminals  301 , which are respectively coupled to the optical connector  2   b . Two sides of each coupling terminal  301  have buckle grooves  302 . 
     The optical connector  2   b  in this embodiment includes a housing  20   b , a coupling terminal  21   b , and a coil structure  22   b . The housing  20   b  has an accommodation space  200   b  for accommodating the coupling terminal  21   b  and a part of the coil structure  22   b . In this embodiment, a buckle arm  201   b  is extended from the housing  20   b . In this embodiment, the buckle arms  201   b  are arranged in pairs. In addition, a positioning structure  23   b  is disposed at an end of the housing  20   b . In this embodiment, the positioning structure  23   b  further has an accommodation groove  230   b  and a leaning structure  231   b , wherein the leaning structure  231   b  is disposed on the periphery of the accommodation groove  230   b , and an opening  232   b  is disposed in a predetermined area of the leaning structure  231   b . A positioning groove  233   b  is arranged on a side wall of the opening  232   b.    
     The coupling terminal  21   b  is accommodated in the accommodation space  200   b  of the housing  20   b  for coupling with one of the coupling terminals  301  on the optical receptacle  30 . The coil structure  22   b  has an elastic coil  220   b , a first fixing coil  221   b , and a second fixing coil  222   b . The outer diameter of the second fixing coil  222   b  is equal to the outer diameter of the elastic coil  220   b  and smaller than the outer diameter of the first fixing coil  221   b . The second fixing coil  222   b  further has an extending section  2220 , which is extended from the accommodation space  200   b  to the opening  232   b  of the accommodation groove  230   b , is connected to the winding section  2211  of the first fixing coil  221   b , and is wound around the accommodation groove  230   b . Another end of the winding section  2211  is connected to the end section  2210 , and the end section  2210  extends toward the side wall of the opening  232   b  and is leaned against the positioning structure  23   b . In this embodiment, the positioning structure  23   b  further has a positioning groove  233   b  formed on the accommodation groove  230   b  and on a side of the opening  232   b . Because the end section  2210  is bent at a predetermined angle by the first fixing coil  221   b  and leaned against the positioning groove  233   b  of the side wall of the opening  232   b , the winding section  2211  and the end section  2210  are respectively clamped on the periphery of the first terminal portion  211  of the coupling terminal  21   b  to produce the effect of fixing the coupling terminal  21   b.    
     When assembling the coil structure  22   b , an end of the elastic coil  220   b  is clamped against the stopping wall  210  on the coupling terminal  21   b , and the entire coil structure  22   b  and the coupling terminal  21   b  are inserted into the accommodation space  200   b  of the housing  20   b . After that, the first fixing coil  221   b  is sleeved into the accommodation groove  230   b  of the positioning structure  23   b , and the end section  2210  is slightly internally pressed and clamped on the positioning groove  233   b  of the leaning structure  231   b . The positioning effect is produced by the force between the end section  2210  and the leaning structure  231   b . After that, the optical connector  2   b  is coupled to the coupling terminal  301  of the optical receptacle  30 , and the buckle arm  201   b  of the optical connector  2   b  is inserted into the buckle groove  302  during coupling, so that the second terminal portion  212  of the coupling terminal  21   b  is coupled with the coupling terminal  301  of the optical receptacle  30 . Eventually, the housing  20   b  is rotated clockwise in a predetermined angle to fix the optical connector  2   b  on the optical receptacle  30 . 
     Since the accommodation groove  230   b  and the leaning structure  231   b  restrain the first fixing coil  221   b , it can be ensured that when the elastic coil  220   b  in the coil structure  22   b  is stretched and compressed along the central axis of the optical connector  2   b , the coil structure  22   b  is not separated from the housing. In addition, since the second fixing coil  222   b  is extended from the first fixing coil  221   b  and arranged in the accommodation space  200   b , the periphery of the first terminal portion  211  of the coupling terminal  21   b  would be restrained by the second fixing coil  222   b . The second fixing coil  222   b  does not have compression or stretching effect. Therefore, when the coupling terminal  21   b  is coupled with the optical receptacle  30 , the shift of the coil structure  22   b  due to the lateral or radial force may be avoided, the stability of coupling terminal  21   b  may be maintained, and the position of the coupling terminal  21   b  of the optical connector  2   b  may be stabilized to ensure the effect of signal connection. 
     Please refer to  FIGS. 5A and 5B , in which  FIG. 5A  is an exploded schematic diagram of another embodiment of the optical connector module,  FIG. 5B  is a schematic cross-sectional view of another embodiment of the optical connector. In this embodiment, the optical connector module  3   a  includes an optical receptacle  30   a  and an optical connector  2   c . The optical receptacle  30   a  is the receptacle of the LC optical connector, but is not limited herein. The optical receptacle  30   a  includes a receptacle body  300   a  and a plurality of coupling terminals  301   a , which are respectively coupled to the optical connector  2   c . Each coupling terminal  301   a  has a buckle groove  302 . 
     In this embodiment, the optical connector  2   c  includes a housing  20   c , a coupling terminal  21   c , and a coil structure  22   c . The housing  20   c  has an accommodation space  200   c  for accommodating the coupling terminal  21   c  and a part of the coil structure  22   c . In this embodiment, a buckle block  24   c  is disposed on the wall surface of the accommodation space  200   c  of the housing  20   c . In this embodiment, the buckle blocks  24   c  are arranged in pairs. In addition, a positioning structure  23   c  is disposed at an end of the housing  20   c . In this embodiment, the positioning structure  23   c  further has an accommodation groove  230   c  and a leaning structure  231   c , wherein the leaning structure  231   c  is disposed on the periphery of the accommodation groove  230   c , and an opening  232   c  is disposed in a predetermined area of the leaning structure  231   c . A positioning groove  233   c  is arranged on a side wall of the opening  232   c.    
     The coupling terminal  21   c  is accommodated in the accommodation space  200   c  of the housing  20   c  for coupling with one of the coupling terminals  301   a  on the optical receptacle  30   a . The coil structure  22   c  has an elastic coil  220   c , a first fixing coil  221   c , and a second fixing coil  222   c . The outer diameter of the second fixing coil  222   c  is equal to the outer diameter of the elastic coil  220   c  and smaller than the outer diameter of the first fixing coil  221   c . The second fixing coil  222   c  further has an extending section  2220 , which is extended from the accommodation space  200   c  to the opening  232   c  of the accommodation groove  230   c , is connected to the winding section  2211  of the first fixing coil  221   c , and is wound around the accommodation groove  230   c . Another end of the winding section  2211  is connected to the end section  2210 , and the end section  2210  extends toward the side wall of the opening  232   c  and is leaned against the positioning structure  23   c . In this embodiment, the positioning structure  23   c  further has a positioning groove  233   c  formed on the accommodation groove  230   c  and on a side of the opening  232   c . Because the end section  2210  is bent in a predetermined angle by the first fixing coil  221   c  and leaned against the positioning groove  233   c  on the side wall of the opening  232   c , the winding section  2211  and the end section  2210  are respectively clamped on the periphery of the first terminal portion  211  of the coupling terminal  21   c  to produce the effect of fixing the coupling terminal  21   c.    
     When assembling the coil structure  22   c , an end of the elastic coil  220   c  is clamped against the stopping wall  210  of the coupling terminal  21   c , and the entire coil structure  22   c  and the coupling terminal  21   c  are inserted into the accommodation space  200   c  of the housing  20   c . After that, the first fixing coil  221   c  is sleeved into the accommodation groove  230   c  of the positioning structure  23   c , and the end section  2210  is slightly internally pressed and clamped on the positioning groove  233   c  of the leaning structure  231   c . The positioning effect is produced by the force between the end section  2210  and the leaning structure  231   c . After that, the optical connector  2   b  is coupled to the coupling terminal  301   a  of the optical receptacle  30   a , and the buckle block  24   c  of the optical connector  2   b  is inserted into the buckle groove  302  during coupling, so that the second terminal portion  212  of the coupling terminal  21   c  is coupled with the coupling terminal  301   a  of the optical receptacle  30   a . Eventually, the housing  20   c  is rotated clockwise in a predetermined angle to make the buckle arm  24   c  engage with the buckle groove  302   a , so that the optical connector  2   c  is fixed on the optical receptacle  30   a.    
     Since the accommodation groove  230   c  and the leaning structure  231   c  restrain the first fixing coil  221   c , it may be ensured that when the elastic coil  220   c  in the coil structure  22   c  is stretched and compressed along the central axis of the optical connector  2   c , the coil structure  22   c  is not separated from the housing. In addition, since the second fixing coil  222   c  is extended from the first fixing coil  221   c  and arranged in the accommodation space  200   c , the periphery of the first terminal portion  211  of the coupling terminal  21   c  would be restrained by the second fixing coil  222   c . The second fixing coil  222   c  does not have compression or stretching effect. Therefore, when the coupling terminal  21   c  is coupled with the optical receptacle  30   a , the shift of the coil structure  22   b  due to the lateral or radial force may be avoided, the stability of coupling terminal  21   b  may be maintained, and the position of the coupling terminal  21   c  of the optical connector  2   c  may be stabilized to ensure the effect of signal connection. 
     Please refer to  FIG. 6A to 6D , in which  FIG. 6A  is an exploded schematic diagram of another embodiment of the optical connector module,  FIG. 6B  is a three-dimensional schematic diagram of the optical connector of  FIG. 6A  from different viewing angles,  FIG. 6C  is a schematic partial cross-sectional view of the coupling position between the optical connector and the optical receptacle, and  FIG. 6D  is a three-dimensional schematic diagram of the optical connector from different viewing angles in the present invention. In this embodiment, the optical connector module  3   b  includes an optical receptacle  30   b  and an optical connector  2   d . The optical receptacle  30   b  includes a receptacle body  300   b  and a plurality of coupling terminals  301   b , which are respectively coupled to the optical connector  2   d . Each coupling terminal  301   b  has a first buckle structure  304   b , which includes a buckle convex portion  302   b  and a buckle concave portion  303   b.    
     In this embodiment, the optical connector  2   d  includes a housing  20   d , a coupling terminal  21   d , and a coil structure  22   d . The housing  20   d  has an accommodation space for accommodating the coupling terminal  21   d  and a part of the coil structure  22   d . It is similar to the aforementioned housing  20   c , and would not be repeated here. In this embodiment, a positioning structure  23   d  is disposed on an end of the housing  20   d . In this embodiment, the positioning structure  23   d  further has an accommodation groove  230   d  and a leaning structure  231   d , wherein the leaning structure  231   d  is disposed on the periphery of the accommodation groove  230   d , and an opening  232   d  is disposed in a predetermined area of the leaning structure  231   d . A positioning groove  233   d  is arranged on a side wall of the opening  232   d.    
     The coupling terminal  21   d  is accommodated in the accommodation space of the housing  20   d  for coupling with one of the coupling terminals  301   b  on the optical receptacle  30   b . The coil structure  22   d  has an elastic coil  220   d , a first fixing coil  221   d , and a second fixing coil  222   d . The outer diameter of the second fixing coil  222   d  is equal to the outer diameter of the elastic coil  220   d  and smaller than the outer diameter of the first fixing coil  221   d . The second fixing coil  222   d  further has an extending section  2220 , which is extended to the opening  232   d  of the accommodation groove  230   d , is connected to the winding section  2211  of the first fixing coil  221   d , and is wound around the accommodation groove  230   d . Another end of the winding section  2211  is connected to the end section  2210 , and the end section  2210  extends toward the side wall of the opening  232   d  and is leaned against the positioning structure  23   d . In this embodiment, the positioning structure  23   d  further has a positioning groove  233   d  formed on the accommodation groove  230   d  on a side of the opening  232   d . Because the end section  2210  is bent in a predetermined angle by the first fixing coil  221   d  and leaned against the positioning groove  233   d  on the side wall of the opening  232   d , the winding section  2211  and the end section  2210  are respectively clamped on the periphery of the first terminal portion  211  of the coupling terminal  21   d  to produce the effect of fixing the coupling terminal  21   d . The first terminal portion  211  is used for coupling with fiber  90 . 
     When assembling the coil structure  22   d , an end of the elastic coil  220   d  is clamped against the stopping wall  210  of the coupling terminal  21   d , and the entire coil structure  22   d  and the coupling terminal  21   d  are inserted into the accommodation space of the housing  20   d . After that, the first fixing coil  221   d  is sleeved into the accommodation groove  230   d  of the positioning structure  23   d , and the end section  2210  is slightly internally pressed and clamped on the positioning groove  233   d  of the leaning structure  231   d . The positioning effect is produced by the force between the end section  2210  and the leaning structure  231   d.    
     After that, the optical connector  2   d  is coupled to the coupling terminal  301   b  of the optical receptacle  30   b , and the second buckle structure  210   d  of the optical connector  2   d  is inserted into the first buckle groove  304  during coupling, so that the second terminal portion  212  of the coupling terminal  21   d  is coupled with the coupling terminal  301   b  of the optical receptacle  30   b . Eventually, the housing  20   d  is rotated clockwise in a predetermined angle to make the second buckle structure  210   d  move into the buckle concave portion  303   b . Since the second buckle structure  201   d  is a convex block, after being embedded in the buckle concave portion  303   b , it would be blocked by the buckle convex portion  302   b  in the rotation direction (or radial direction), and would be blocked by the stopping block  305  in the axial direction, so that the optical connector  2   d  is avoided being separated from the optical connector receptacle  30   b , and the optical connector  2   d  is fixed on the optical receptacle  30   b . It should be noted that if it is to be separated, take  FIG. 6C  as an example, the housing  20   d  shall be rotated by an external force, so that the second buckle structure  201   d  is released from the buckle convex portion  302   b . At this time, the second buckle structure  201   d  is also separated from the stopping block  305   b  in the axial direction, and the optical connector  2   d  may be taken away from the optical receptacle  30   b.    
     Since the accommodation groove  230   d  and the leaning structure  231   d  restrain the first fixing coil  221   d , it may be ensured that when the elastic coil  220   d  in the coil structure  22   d  is stretched and compressed along the central axis of the optical connector  2   d , the coil structure  22   d  is not separated from the housing. In addition, since the second fixing coil  222   d  is extended from the first fixing coil  221   d  and arranged in the housing  20   d , the periphery of the first terminal portion  211  of the coupling terminal  21   d  would be restrained by the second fixing coil  222   d . The second fixing coil  222   d  does not have compression or stretching effect. Therefore, when the coupling terminal  21   d  is coupled with the optical receptacle  30   b , the shift of the coil structure  22   d  due to the lateral or radial force may be avoided, the stability of coupling terminal  21   d  may be maintained, and the position of the coupling terminal  21   d  of the optical connector  2   d  may be stabilized to ensure the effect of signal connection. 
     It should be noted that the coil structure  22 ,  22   a ,  22   b ,  22   c ,  22   d  of the present invention is achieved through the positioning structure  23 ,  23   a  and  23   b ,  23   c ,  23   d  being integrally formed with the housing  20 ,  20   a ,  20   b ,  20   c ,  22   d  to achieve the effect of fixing the elastic coil, so that it&#39;s not necessary to additionally provide a supporting structure of the stopping coil. Therefore, the length of the housing  20 ,  20   a ,  20   b ,  20   c ,  20   d  may be shortened to achieve the effect of saving space. 
     In summary, through the arrangement of the elastic element in the optical connector of the present invention, one end of the elastic element may be axially positioned and the coupling terminal may be positioned radially. It may avoid the problem that the coupling terminal is shift due to the lateral force when inserted into the optical receptacle, and ensure that the elastic element may only be elastically compressed or stretched in the central axis, so as to ensure the position of the coupling terminal in the axial direction and the electrical connection between the coupling terminal and the optical receptacle. 
     It will be understood that the above description of embodiments is given by way of example only and that various modifications may be made by those with ordinary skill in the art. The above specification, examples, and data provide a complete description of the present invention and use of exemplary embodiments of the invention. Although various embodiments of the invention have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those with ordinary skill in the art could make numerous alterations or modifications to the disclosed embodiments without departing from the spirit or scope of this invention.