Abstract:
The present invention generally relates to a method for manufacturing a one-piece LC type optical fiber adapter, more particularly to a method that is simpler and easier to assemble the LC type optical fiber adapter.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of a co-pending U.S. patent application Ser. No. 12/199,581 for “ONE-PIECE LC TYPE OPTICAL FIBER ADAPTER” filed Aug. 27, 2008. The content of which is incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to a method for manufacturing a one-piece LC type optical fiber adapter, more particularly to a method that is simpler and easier to assemble the LC type optical fiber adapter. 
     2. Description of the Prior Art 
     Fiber optics has revolutionized communication through out the world. With the increased used of fiber optics it has become increasingly important to be able to connect and disconnect fiber optic cables from various sources. Two fiber optic cables can be optically coupled so that they are in communication with each other by using connectors and an adapter, thereby putting each fiber optic cable in communication with the other. The connectors are placed on the end of each cable and then plugged into the adapter. The adapter has two openings each one designed to receive a connector. 
     The conventional LC type adapter consists of two halves, each halve being identical. Each half consists generally of a rectangular cylinder having a flange at one end. Inside each half would be placed half of an inner housing. The inner housing is generally a round cylinder with a flange at one end. Each adapter half has a ridge located just inside from its flange so that the inner housing could be placed in the adapter through the opening proximate to the flange on the adapter half. Once the inner housing is inserted into each adapter half, the two halves are connected by ultrasonically welding the two flanges of the adapter halves together. 
     However, the above design presents serious problems. The cables are naturally flexed in use when the adapter remains fixed. The related stress of this situation can cause the two halves of the adapter to separate from each other after time. In the prior art, this problem can be solved by constructing the adapter halves from metal which gives the adapter enough strength to withstand these stresses. However, this too presented a problem as metal is much more expensive to purchase and mold than the plastic one. 
     Accordingly, there exists a need to provide an LC type optical fiber adapter so as to develop a method for manufacturing the LC type optical fiber adapter for solving the aforesaid problems. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a method for manufacturing a one-piece LC type optical fiber adapter that has fewer parts than a conventional one. The method is simpler and easier to assemble the LC type adapter of the present invention. In addition, the main body of the LC type adapter is unitary thereby avoiding the prior art problem that the stresses cause the two halves of the adapter to separate from each other after time. 
     In order to achieve the above object, the method for manufacturing the one-piece LC type optical fiber adapter comprises the steps of:
         (1) providing a main body having an axial cavity, which is defined by a top side-wall, a bottom side-wall, a right side-wall, and a left side-wall;   (2) dividing the axial cavity into two halves through a compartment wall, which is parallel to the right side-wall and left side-wall and connected with the top side-wall and bottom side-wall and has a surface;   (3) forming the half of the axial cavity, a right axial cavity, through the top side-wall, bottom side-wall, compartment wall, and right side-wall, wherein a first right opening and a second right opening are formed at the two ends of the right axial cavity respectively;   (4) forming the other half of the axial cavity, a left axial cavity, through the top side-wall, bottom side-wall, compartment wall, and left side-wall, wherein a first left opening and a second left opening are formed at the two ends of the left axial cavity respectively;   (5) forming a pair of tabs on the exterior of the main body, wherein the one tab is on the right side-wall and the other tab is on the left side-wall;   (6) forming a pair of parallel ridges on the inner surface of the bottom side-wall of the axial cavity of the main body so as to define a groove, wherein the ridges and the groove are perpendicular to the bottom side-wall and divide the compartment wall into two halves, the groove being located at the middle between the first openings and the other middle between second openings of the main body;   (7) forming two grooves on the right side-wall and left side-wall respectively, wherein the two grooves are collinear with the groove;   (8) forming four pairs of protrusions, wherein the first pair of protrusions are at the locations near the right opening on the joint of the right side-wall with the bottom side-wall and on the joint of the compartment wall with the bottom side-wall, the second pair of protrusions being at the locations near the left opening on the joint of the left side-wall with the bottom side-wall and on the joint of the compartment wall with the bottom side-wall, the third pair of protrusions being at the locations near the right opening on the joint of the right side-wall with the bottom side-wall and on the joint of the compartment wall with the bottom side-wall, and the fourth pair of protrusions being at the locations near the left opening on the joint of the left side-wall with the bottom side-wall and on the joint of the compartment wall with the bottom side-wall;   (9) forming an access opening on the top side-wall, wherein the location of the access opening is corresponding to the two tabs;   (10) providing two inner housing halves that can be inserted into the axial cavity of the main body through the access opening, wherein the two inner housing halves are identical, each half comprising at least two hollow cylinders, a flange located at the two ends of the same side of the cylinders, the thickness of the two flanges of combining the two inner housing halves being equal to the widths of the grooves;   (11) providing two sleeves, wherein the two cylinders of each of the inner housing halves are coaxial in the main body and define two cylinders, and the two hollow sleeves being accommodated in the cylinders respectively;   (12) combining the inner housing halves;   (13) disposing the combined inner housing halves in the main body through aligning the flange of the inner housing half with collinear grooves; and   (14) integrating a cover to the access opening of the main body, wherein the cover comprises a bottom surface, the surface of the compartment wall being firmly attached to the bottom surface.       

     Other and further features, advantages, and benefits of the invention will become apparent in the following description taken in conjunction with the following drawings. It is to be understood that the foregoing general description and following detailed description are exemplary and explanatory but are not to be restrictive of the invention. The accompanying drawings are incorporated in and constitute a part of this application and, together with the description, serve to explain the principles of the invention in general terms. Like numerals refer to like parts throughout the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The objects, spirits, and advantages of the preferred embodiments of the present invention will be readily understood by the accompanying drawings and detailed descriptions, wherein: 
         FIG. 1  is an elevated perspective view of a conventional LC type fiber adapter; 
         FIG. 2  is an elevated perspective view of the main body of the fiber adapter according to the present invention; 
         FIG. 3  is an exploded view of the fiber adapter of the present invention; 
         FIG. 4  is an elevated perspective view of the fiber adapter of the present invention, wherein the inner housing has been placed in the main body; and 
         FIG. 5A and 5B  (hereinafter referred to as  FIG. 5 ) collectively are a flow chart of a method for manufacturing the one-piece LC type optical fiber adapter of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Following preferred embodiments and figures will be described in detail so as to achieve aforesaid objects. 
     Referring to  FIG. 1 , a conventional LC type fiber connector  100  has a generally rectangular shape with a square cross section. The outer surface of the connector  100  includes a spring latch  120 . The spring latch  120  is molded into the outer housing of the connector and includes a living hinge  125  which allows tab  126  to be moved up and down in a direction perpendicular to the central axis  150 - 150  of the connector  100 . In addition, a ferrule  140  protrudes from the opening Ill of a two-piece assembly comprising housing  110  and cover  130  which have been ultrasonically bonded together. A spring (not shown in the figure) is located inside the two-piece assembly to allow the ferrule  140  to move back and forth through the opening  111 . The spring latch  120  includes a pair of shoulders  121  that are positioned on opposite sides of the tab  126 . 
     Referring to  FIGS. 2 to 4 , the duplex fiber adapter  200  of the present invention includes a unitary molded main body  205  and a cover  300 . In the preferred embodiment, the main body  205  has an axial cavity defined by top side-wall  210 , bottom side-wall  211 , right side-wall  212  and left side-wall  213 . The axial cavity is divided into two halves by a compartment wall  214  that is parallel to the right side-wall  212  and left side-wall  213  and connects with the top side-wall  210  and bottom side-wall  211 . The half of the axial cavity defined by the top side-wall  210 , bottom side-wall  211 , compartment wall  214  and right side-wall  212  is named as the right axial cavity and the other half of the axial cavity defined by the top side-wall  210 , bottom side-wall  211 , compartment wall  214  and left side-wall  213  is named as the left axial cavity. The right axial cavity has opposing first right opening  207   a  and second right opening  208   a  and the left axial cavity has opposing first left opening  207   b  and second left opening  208   b.    
     Located on the exterior of the main body  205  is a pair of tabs  201  and  202 . One tab  202  is located on the right side-wall  212  and the other tab  201  is located on the left side wall  213 . The tabs  201  and  202  are operative in supporting the adapter  100  on a surface. The inner cavity of the main body  205  contains a pair of parallel ridges  235  and  236  located on the inner surface of the bottom side-wall  211 . The ridges  235  and  236  are perpendicular to the axial cavity of the main body  205  and divide the compartment wall  214  into two halves. 
     The ridges  235  and  236  define a groove  238  which is perpendicular to the axial cavity of the main body  205 . The groove  238  is half way between the first openings  207   a ,  207   b  and second openings  208   a ,  208   b  of the main body  205 . The width of the groove  238  is equal to the thickness of combined flanges  450  of the inner housing halves  410  and  420 . The right side-wall  212  and left side-wall  213  each has a groove  239  that is collinear with the groove  238 . 
     Located near the right opening  207   a  on the joint of the right side-wall  212  with the bottom side-wall  211  and on the joint of the compartment wall  214  with the bottom side-wall  211  are protrusions  262 . The protrusions  262  are also located near the left opening  207   b  on the joint of the left side-wall  213  with the bottom side-wall  211  and on the joint of the compartment wall  214  with the bottom side-wall  211 . Similarly, these protrusions  262  are also located near the openings  208   a ,  208   b  on the joints of the bottom side-wall  211  with the right side-wall  212 , compartment wall  214  and left side-wall  213 , respectively. 
     An access opening  250  is located on the top side-wall  210 . The access opening  250  allows inner housing halves  410  and  420  to be inserted into the axial cavity of the main body  205  and also allows the main body  205  to be constructed by injection molding. 
     The inner housing halves  410  and  420  are identical. Each of the inner housing halves  410  and  420  is constructed of plastic by an injection molding process. Each half includes two hollow cylinders  440  and a rectan2ular flange  450  located at one end of the cylinder  440 . Two halves  410  and  420  are connected at their respective flanges  450  respectively so as to define two common cylinders. Two flanges  450  define a thickness which is equal to the widths of the groove  238  and  239 . The inner housing halves  410 ,  420  are placed in the main body  205  by aligning the flange  450  of the inner housing half  410  with collinear grooves  238  and  239  and sliding it into place within the main body  205 . The other inner housing half  420  is inserted into the main body  205  in the same fashion. 
     The cylinders  440  of the inner housing halves  410  and  420  are coaxial in the main body  205  and define two common cylinders. Located in each of the common cylinders is a hollow sleeve  500  with a generally cylindrical shape. The cover  300  covers the access opening  250  and can be ultrasonically welded to the main body  205 . 
     With reference to  FIG. 5 , which is a flow chart of a method for manufacturing the one-piece LC type optical fiber adapter of the present invention. The method includes the steps of: 
     ( 5001 ) providing a main body  205  having an axial cavity, which is defined by a top side-wall  210 , a bottom side-wall  211 , a right side-wall  212 , and a left side-wall  213 , wherein the main body  205  is constructed of plastic by an injection molding process; 
     ( 5002 ) dividing the axial cavity into two halves through a compartment wall  214 , which is parallel to the right side-wall  212  and left side-wall  213  and connected with the top side-wall  210  and bottom side-wall  211  and has a surface  2141 ; 
     ( 5003 ) forming the half of the axial cavity, a right axial cavity, through the top side-wall  210 , bottom side-wall  211 , compartment wall  214 , and right side-wall  212 , wherein a first right opening  207   a  and a second right opening  208   a  are formed at the two ends of the right axial cavity respectively; 
     ( 5004 ) forming the other half of the axial cavity, a left axial cavity, through the top side-wall  210 , bottom side-wall  211 , compartment wall  214 , and left side-wall  213 , wherein a first left opening  207   b  and a second left opening  208   b  are formed at the two ends of the left axial cavity respectively; 
     ( 5005 ) forming a pair of tabs  201  and  202  on the exterior of the main body  205 , wherein the one tab  202  is on the right side-wall  212  and the other tab  201  is on the left side-wall  213 ; 
     ( 5006 ) forming two indentations  2391  on the two tabs  201  and  202  on the joint of the tab  201  with the top side-wall  210  and the joint of the tab  202  with the top side-wall  210  respectively, wherein the two indentations  2391  are collinear with the two grooves  239 ; 
     ( 5007 ) forming a pair of parallel ridges  235  and  236  on the inner surface of the bottom side-wall  211  of the axial cavity of the main body  205  so as to define a groove  238 , wherein the ridges  235  and  236  and the groove  238  are perpendicular to the bottom side-wall  211  and divide the compartment wall  214  into two halves, the groove  238  being located at the middle between the first openings  207   a  and  207   b  and the other middle between second openings  208   a  and  208   b  of the main body  205 ; 
     ( 5008 ) forming two grooves  239  on the right side-wall  212  and left side-wall  213  respectively, wherein the two grooves  239  are collinear with the groove  238 ; 
     ( 5009 ) forming four pairs of protrusions  262 , wherein the first pair of protrusions  262  are at the locations near the right opening  207   a  on the joint of the right side-wall  212  with the bottom side-wall  211  and on the joint of the compartment wall  214  with the bottom side-wall  211 , the second pair of protrusions  262  being at the locations near the left opening  207   b  on the joint of the left side-wall  213  with the bottom side-wall  211  and on the joint of the compartment wall  214  with the bottom side-wall  211 , the third pair of protrusions  262  being at the locations near the right opening  208   a  on the joint of the right side-wall  212  with the bottom side-wall  211  and on the joint of the compartment wall  214  with the bottom side-wall  211 , and the fourth pair of protrusions  262  being at the locations near the left opening  208   b  on the joint of the left side-wall  213  with the bottom side-wall  211  and on the joint of the compartment wall  214  with the bottom side-wall  211 ; 
     ( 5010 ) forming an access opening  250  on the top side-wall  210 , wherein the location of the access opening  250  is corresponding to the two tabs  201  and  202  and constructed by an injection molding process; 
     ( 5011 ) providing two inner housing halves  410  and  420  that can be inserted into the axial cavity of the main body  205  through the access opening  250 , wherein the two inner housing halves  410  and  420  are identical and constructed of plastic by an injection molding process, each half  410 / 420  including at least two hollow cylinders  440 , a flange  450  being located at the two ends of the same side of the cylinders  440  and shaped as a rectangular member, the thickness of the two flanges  450  of combining the two inner housing halves  410  and  420  being equal to the widths of the grooves  238  and  239 ; 
     ( 5012 ) providing two sleeves  500 , wherein the two cylinders  440  of each of the inner housing halves  410  and  420  are coaxial in the main body  205  and define two cylinders, and the two hollow sleeves  500  being accommodated in the cylinders  440  respectively; 
     ( 5013 ) combining the inner housing halves  410  and  420 ; 
     ( 5014 ) disposing the combined inner housing halves  410  and  420  in the main body  205  through aligning the flange  450  of the inner housing half  410  with collinear grooves  238  and  239 ; and 
     ( 5015 ) integrating a cover  300  to the access opening  250  of the main body  205  by way of ultrasonic welding, wherein the cover  300  includes two ribs  3001  and a bottom surface  3002 , the two ribs  3001  being tightly embedded into the two indentations  2391  and the surface  2141  of the compartment wall  214  being firmly attached to the bottom surface  3002 , as shown in  FIG. 4 . 
     In operation the connector  100  is inserted into the main body  205  from, for example, the first right opening  207   a . The shoulders  121  positioned on the opposite sides of the tab  126  of the spring latch  120  are pushed by the protrusions  262  to cause the spring latch  120  to be deflected downward during the insertion into the main body  205 . The ferrule  140  of the connector  100  is inserted into one end of the hollow sleeve  500  in the right axial cavity. When the shoulders  121  pass over the protrusions  262 J the spring latch  120  is then returned to its original position by its own restorative force to have the shoulders  121  moved upward to position behind the protrusions  262 . The protrusions  262  can stop the backward movement of the shoulders  121  to prevent the connector  100  from being pulled out from the adapter  200 . Another connector  100  can be inserted into the main body  205  from the second right opening  208   a  in the same manner to have its ferrule  140  to be inserted into the other end of the sleeve  500  in the right axial cavity. The end face of the ferrule  140  will be brought into contact with that of the previous ferrule  140 . Similarly, two connectors  100  can be inserted into the main body  205  from the first left opening  207   b  and the second left opening  208   b  respectively to optically couple with each other. 
     In addition to duplex fiber adapter, the fiber adapter of the present invention can also be designed to couple four pairs of connectors (not shown in the figure). More specifically, the axial cavity in the main body of the adapter is divided into four parts by three parallel compartment walls. Four connectors can be inserted into the front ends of the four parts of the axial cavity respectively in the above-described manner. Similarly, another four connectors can be inserted into the rear ends of the four parts of the axial cavity to couple with the opposite connectors, respectively. Since the structure of this adapter is substantially identical to that of the adapter  200 , any further illustrations of such adapter are omitted herein. 
     Since the main body of the fiber adapter according to the present invention is unitary, the prior art problem that the stresses cause the two halves of the adapter to separate from each other after time can be avoided. 
     Although the invention has been disclosed and illustrated with reference to particular embodiments, the principles involved are susceptible for use in numerous other embodiments that will be apparent to persons skilled in the art. This invention is, therefore, to be limited only as indicated by the scope of the appended claims.