JP5387359B2 - Optical cable connector and optical cable connector and optical cable assembly method - Google Patents

Description

  The present invention relates to an optical cable connector, an optical cable connector and an optical cable assembling method, and more particularly, an optical cable connector structure for optically connecting optical fibers of an optical cable for transmitting an optical signal, and an optical cable connector of this type. The present invention relates to an assembling method.

  In general, an optical cable using an optical fiber (also referred to as an optical fiber cable) is widely used for home and industrial information communication because it enables high-speed communication of a large amount of information. In addition, for example, automobiles are equipped with various electrical components (for example, a car navigation system), and are often used for optical communication of these electrical components. The optical fiber ends are optically connected to each other (connectable so that optical signals can be transmitted), and a connector to which one optical cable is attached and a connector to which the other optical cable is attached are detachably fitted. Various optical cable connectors (also referred to as optical connectors or optical fiber connectors) have been proposed (see, for example, Patent Document 1).

  An example of this type of optical cable connector is shown in FIG. FIG. 9 shows only one connector (female connector). The optical cable connector 101 includes a connector housing 102, a ferrule 104 housed in the connector housing 102, and a coil spring 106 that biases the ferrule 104. Specifically, the optical fiber 109 exposed for a predetermined length from the end of the optical cable 108 is fixed to the ferrule 104, and the ferrule 104 is housed in the connector housing 102 in a state of being biased toward the distal end side by the coil spring 106. The On the other hand, the optical cable 108 is fixed to the connector housing 102 by a method described later. When a pair of male and female connectors are fitted in this state, the front end surfaces of the ferrule 104 urged by the coil spring 106 (which are mirror-finished to reduce connection loss) are brought into contact with each other, so that the male and female connectors The optical fiber 109 is optically connected.

  The optical cable 108 is fixed to the connector housing 102 of the optical cable connector 101 by the following method. As a simple method, for example, as shown in FIG. 9A, a configuration in which an optical cable 108 is fixed to a connector housing 102 with an adhesive S is known (see, for example, Patent Document 2).

  On the other hand, as shown in FIGS. 9B and 9C, a cable holding member having a predetermined shape is inserted from the mounting hole 102a provided in the connector housing 102, and the optical cable 108 is sandwiched by the cable holding member H1. For example, a method of fixing the optical cable 108 to the connector housing 102 by piercing the optical cable 108 with the cable holding member H2 is known. That is, the connector housing 102 and the optical cable 108 are mechanically connected via the cable holding members H1 and H2 (see, for example, Patent Document 3). As another example of a connection method using such a cable holding member, a configuration using a sleeve fixed to the end portion of an optical cable as a cable holding member as described in Patent Document 4 is also known. .

Japanese Patent Laid-Open No. 2002-169061 JP 2003-149446 A JP 2000-147317 A JP 2008-241729 A

  However, the method of fixing the optical cable to the connector housing using an adhesive is difficult to handle the adhesive and has poor workability. Further, since the application state of the adhesive varies depending on the operator, the reliability of fixing the optical cable to the connector housing is low. In particular, when used in a high-temperature environment, there is a problem that the reliability of fixing is further lowered unless an adhesive corresponding to that is selected. On the other hand, in the case of the connection method using the cable holding member, there is a problem that the process of attaching the cable holding member to the connector housing becomes a burden (labor), and the assembly cost (manufacturing cost) increases.

  In any of the above fixing methods, it is necessary to pass the connector housing through the optical cable at the beginning of the assembly process. In other words, since the ferrule urged toward the tip side and the coil spring that urges the ferrule cannot be accommodated from the rear of the connector housing, the coil spring or ferrule must be connected to the connector unless the optical cable is first passed through the connector housing. It cannot be accommodated in the housing. That is, a coil spring or a ferrule must be assembled to the optical cable with the connector housing being passed through the optical cable. In such an assembly process, the connector housing that is first passed through the optical cable obstructs the subsequent assembly work of the coil spring and ferrule and the mirror surface treatment work of the tip surface of the ferrule. It contributed to the decline.

  The problem to be solved by the present invention is to provide an optical cable connector that is excellent in assembling workability and can securely fix an optical cable to a connector housing, and an optical cable connector and an optical cable assembling method.

In order to solve the above-mentioned problems, an optical cable connector according to the present invention includes a ferrule to which a terminal portion of an optical fiber exposed for a predetermined length from the tip of an optical cable in which the optical fiber is covered with a sheath is fixed, An optical cable connector having a coil spring urging the ferrule, wherein a ferrule housing part for housing the ferrule, a coil spring housing part for housing the coil spring, and a fixing member housing part for housing a terminal portion of the sheath A connector housing having a housing body formed so as to open toward the outside and a housing cover that is attached to the housing body so as to cover the openings of the housing portions, and a terminal portion of the sheath. The barrel portion to be caulked and the fixing member provided on the tip side from the barrel portion Comprising a cable fixing member having a fixing portion fixed to volume unit, on the inner side of the fixed portion of the cable fixing member, the spring entry allowance space to permit entry of the coil spring is formed, Nature of the coil spring The gist is that the length is shorter than the length from the rear end surface of the ferrule in the axial direction of the optical cable to the front end surface of the fixing portion of the cable fixing member plus the length of the spring entry allowable space. Is.

The concrete structure, the spring entry allowance space, structure provided on the inner side of the fixed portion of the cable fixing member formed in a substantially U-shaped cross section can be exemplified.

  And the spring latching part which latches the said coil spring should just be provided in the rear end of the said ferrule.

The optical cable connector and the optical cable assembling method according to the present invention include exposing the optical fiber by peeling a predetermined length from the tip of the optical cable sheath in which the optical fiber is covered with the sheath. A cable fixing member having a fixing portion formed on the distal end side, a cable fixing member fixing step for fixing the barrel portion to the optical cable by caulking the barrel portion to the end portion of the sheath; and an exposure on the distal end side of the optical cable. A coil spring insertion step for inserting a coil spring into the optical fiber, a ferrule fixing step for fixing a ferrule to the tip portion of the optical fiber through which the coil spring is inserted, and a housing main body formed to open outward To open the ferrule in the ferrule housing part, also toward the outside A ferrule and a coil spring housing process for housing the coil spring so that the ferrule is urged toward the distal end side in a coil spring housing portion formed in the Uzing body, and the cable fixing member fixed to the optical cable. A cable fixing step for fixing the fixed portion of the fixed portion to a fixing member accommodating portion formed in the housing body so as to open outward, a ferrule accommodating portion in which the ferrule is accommodated, and a coil in which the coil spring is accommodated spring accommodating portion, and the housing cover deposition step of fixing portions of the cable fixing member is adhered to the housing cover to the housing body so as to cover the opening of the fixing member accommodation portion fixed, only contains the cable fixing Inside the fixed portion of the member, a spring entry allowance space that allows entry of the coil spring is formed. In the ferrule fixing step, the natural length of the coil spring is longer than the length from the rear end surface of the ferrule to the tip of the cable fixing member in the axial direction of the optical cable plus the length of the entry allowable space. The gist of the invention is to fix the ferrule at a position to be shortened .

The concrete structure, the spring entry allowance space, structure provided on the inner side of the fixed portion of the cable fixing member formed in a substantially U-shaped cross section can be exemplified.

  Further, a spring locking portion for locking the coil spring is provided at the rear end of the ferrule, and a coil spring locking step for locking the coil spring to the coil spring locking portion after the ferrule fixing step. It should be included.

  In the optical cable connector (an assembly method of the optical cable connector and the optical cable) according to the present invention, the optical cable can be securely fixed to the connector housing by fixing the cable fixing member fixed to the end portion of the sheath to the housing body. it can. The cable fixing member can be fixed to the optical cable by caulking its barrel portion to the end portion of the sheath (it can be fixed by a method and apparatus similar to the case of caulking a generally known crimp terminal to an electric wire). Therefore, assembly work is easy. The connector housing is divided into a housing main body and a housing cover. The housing main body includes a ferrule housing portion for housing a ferrule, a coil spring housing portion for housing a coil spring, and a terminal portion of the sheath. Since the fixing member housing portion for housing the housing is formed so as to open toward the outside, it is not necessary to pass the connector housing through the optical cable in advance as in the prior art. That is, after fixing the cable fixing member to the sheath, inserting the coil spring into the optical fiber, and fixing the optical fiber to the ferrule first, these members can be stored and fixed in the connector housing. Excellent assembly workability. For example, the workability of the mirror surface processing operation on the tip surface of the ferrule is greatly improved as compared with the conventional case.

  The cable fixing member has a predetermined length that allows the coil spring to enter inside by fixing the fixing portion of the cable fixing member to a substantially U-shaped cross section (specifically, the natural length of the coil spring is the axial direction of the optical cable). If a spring entry allowance space having a length shorter than the length from the rear end face of the ferrule to the tip end face of the fixing portion of the cable fixing member plus the length of the spring entry allowance space is provided, In a state before the ferrule or coil spring is stored in the main body, the biasing force of the coil spring does not act on the ferrule. That is, since the mirror surface processing operation of the tip surface of the ferrule can be performed in a state where the spring biasing force does not contribute to the ferrule, the assembling workability is further improved. Furthermore, since the spring entry allowance space is provided inside the fixing portion of the cable fixing member, the increase in size of the connector in the axial direction of the optical cable due to the provision of the spring entry allowance space is not caused. That is, according to such a configuration, assembly workability can be improved without causing an increase in size of the connector.

  And if the spring latching part which latches a coil spring is provided in the rear end of a ferrule, the coil located between the cable fixing member fixed to the terminal part of a sheath, and the ferrule fixed to the optical fiber The spring can be locked to the ferrule. As a result, the coil spring inserted into the optical fiber does not interfere with the assembling work (particularly, the mirror surface finishing work on the tip surface of the ferrule), and a load due to the weight of the coil spring is applied to the ultrafine optical fiber. This prevents the possibility of disconnection of the optical fiber.

It is a disassembled perspective view of the optical cable connector concerning one Embodiment of this invention. It is sectional drawing of the optical cable connector concerning one Embodiment of this invention. It is the figure which expanded and showed the housing main body of the male connector with which the optical cable connector shown to FIG. 1 and FIG. 2 is provided. It is the figure which expanded and showed the housing main body of the female connector with which the optical cable connector shown to FIG. 1 and FIG. 2 is provided. It is an external view of the cable fixing member with which the optical cable connector shown in FIG.1 and FIG.2 is equipped, (a) from the front end side, (b) from the downward direction, (c) The top view seen from the side ((c ) Is a partial cross-sectional view). It is the external appearance perspective view which showed the state which fixed the cable fixing member shown in FIG. 5 to the optical cable. (A) is an external appearance perspective view of the assembly which assembles an optical cable, a cable fixing member, a ferrule, and a coil spring, (b) is an external appearance perspective view of this assembly assembled in a housing body (male connector). FIG. It is sectional drawing of the assembly formed by assembling an optical cable, a cable fixing member, a ferrule, and a coil spring. It is the schematic for demonstrating the attachment structure to the connector housing of the conventional optical cable, (a) shows fixation by an adhesive agent, (b) (c) shows fixation using a cable holding member.

  An optical cable connector 1 according to an embodiment of the present invention will be described in detail with reference to the drawings. Here, FIG. 1 is an exploded perspective view of the optical cable connector 1 according to the present embodiment, and FIG. 2 is an exploded sectional view of the optical cable connector 1. In these drawings, the optical cable 90 assembled to the optical cable connector 1 is also shown. In the following description, unless otherwise specified, the distal end side refers to the fitting side of the male connector 20 and the female connector 30 and the proximal end side refers to the opposite side. Further, the term “axial direction” simply refers to the axis of the optical cable 90, that is, the horizontal direction in FIG. 2, and the term “vertical direction” refers to the vertical direction in FIG.

  The optical cable connector 1 includes a pair of male connector 20 and female connector 30, a cable fixing member 40 fixed to the optical cable 90, a ferrule 50 and a coil spring housed in each of the male connector 20 and the female connector 30. 60.

  The optical cable 90 to which each of the male connector 20 and the female connector 30 is fixed is an optical fiber 92 that transmits an optical signal (in this embodiment, two optical fibers 92 (one for transmission and one for reception)). And a tension member 94 for securing the strength of the cable (preventing disconnection of the optical fiber 92 due to bending of the cable or the like) is covered with a sheath 96. The optical cable 90 connected to the optical cable connector 1 has an optical fiber 92 of a predetermined length exposed from the tip, and the fitting of the male connector 20 and the female connector 30 results in the optical cable 90 connected to each connector. The optical fibers 92 are in an optically connected state.

  Hereinafter, the configuration of the optical cable connector 1 will be described in detail. Both the male connector 20 and the female connector 30 (connector housing) have housing bodies 22 and 32 and housing covers 24 and 34. The housing main bodies 22 and 32 have a structure that is notched from the position of a predetermined length (parts that become the hood portions 228 and 328) from the distal end to the proximal end. FIG. 3 shows an enlarged view of the housing body 22 of the male connector 20 and FIG. 4 shows an enlarged view of the housing body 32 of the female connector 30. The male connector 20 and the female connector 30 included in the optical cable connector 1 are not significantly different from each other in the characteristic portions of the present embodiment. Therefore, in the following description, the configuration of the male connector 20 will be mainly described.

  A ferrule housing part 222 for housing the ferrule 50, a coil spring housing part 224 for housing the coil spring 60, and the cable fixing member 40 are fixed to the housing main body 22 of the male connector 20 along the notched portion. The fixed member accommodating portion 226 to be formed is formed in a predetermined size. These housing portions are opened outward (in a direction orthogonal to the axial direction) by cutting out a part of the housing.

  Among these accommodating portions, the ferrule accommodating portion 222 formed at the most distal end side is formed in a shape that allows the ferrule 50 to move in the axial direction, and will be described later, specifically a ferrule 50 (specifically, a main body portion of the ferrule 50). The ferrule 50 is held so as to surround a part of the peripheral surface (both side surfaces and the lower end surface). As shown in the figure, the ferrule housing part 222 is formed such that the distal end side (width detail 222a) is slightly smaller in width than the proximal end side (wide width part 222b).

  The coil spring housing part 224 is provided between the ferrule housing part 222 and the fixing member housing part 226 and is formed such that its axial length is smaller than the natural length of the coil spring 60. Further, the depth of the recess is formed to a depth that prevents the coil spring 60 from popping out carelessly (for example, a depth of 2/3 or more of the diameter of the coil spring 60).

  The fixing member accommodating portion 226 is formed in a shape that allows the fixing portion 42 of the cable fixing member 40 to be described later to be mounted, and a part of the fixing member accommodating portion 226 has a tapered shape that gradually increases in width toward the tip. Further, two press-fit holes 226a elongated in the axial direction (only one press-fit hole 226a is shown in FIG. 3 on the inner bottom surface of the fixing member accommodating portion 226. The other press-fit hole 226a is the shown press-fit hole. 226a and the target positional relationship).

  A hood portion 228 having a substantially rectangular cross section is formed on the distal end side of the housing body 22. When the ferrule 50 is housed in the ferrule housing portion 222 of the housing main body 22, the front end surface 52 a of the ferrule 50 is protected by the hood portion 228. Specifically, when mating with the female connector 30 that is the mating counterpart, even if the female connector 30 is inclined, the female connector 30 may abut against the tip surface 52a of the ferrule 50. There is no shape (the tip surface 52a of the ferrule 50 is not damaged by the female connector 30).

  The housing cover 24 is attached to the notched portion of the housing main body 22 so as to cover the openings of the three accommodating portions formed in the housing main body 22. As described later, the housing cover 24 prevents the ferrule 50, the coil spring 60, and the cable fixing member 40 that are housed in the housing portions from dropping off. A method of attaching the housing cover 24 to the housing main body 22 is not particularly limited. In the present embodiment, four locking holes 242 provided in the housing cover 24 (only two locking holes 242 are shown in FIG. 1. The remaining two are opposed to the illustrated locking holes 242, respectively. Each of which is in a positional relationship is locked with four locking protrusions 229 provided on the housing body 22 (only two locking protrusions 229 are shown in FIGS. 1 and 3, and the remaining two are illustrated). Each of the locking protrusions 229 to be opposed to each other).

  The cable fixing member 40 is a metal member formed by pressing. The external view is shown in FIG. As shown in FIG. 5, the cable fixing member 40 has a fixing portion 42 and a barrel portion 44.

  The fixing portion 42 is a portion that is accommodated in the fixing member accommodating portion 226 of the housing body 22, and is formed on the distal end side from the barrel portion 44. The cross section (cross section cut by a plane orthogonal to the axial direction) is formed in a substantially U shape (see FIG. 5A), and the shape seen from above is substantially the same as the shape of the fixing member accommodating portion 226 (strictly Is formed so that the size of the fixing member housing portion 226 is slightly larger (see FIG. 5B). That is, like the fixing member housing portion 226, a part of the taper shape gradually increases in width toward the tip when viewed from above. And the front-end | tip part (upper end part of the fixing | fixed part 42 in FIG. 5 (a), FIG.5 (c)) of this fixing | fixed part 42 is press-fitted in the press-fit hole 226a formed in the inner bottom face of the fixing member accommodating part 226. It is a press-fit portion 421. By press-fitting the press-fitting portion 421 into the press-fitting hole 226a, the cable fixing member 40 is fixed to the fixing member accommodating portion 226, that is, the optical cable 90 is fixed to the housing body 22.

  Thus, since the fixed part 42 is formed in a substantially U-shaped cross section, a space of a predetermined size exists inside thereof. In the present embodiment, this space is referred to as a spring entry allowance space 46 (dotted cross-hatching region shown in FIGS. 5B and 5C). The spring entry allowance space 46 is a space for allowing entry of the coil spring 60 and allowing the fixing portion 42 and the coil spring 60 to be positioned to overlap each other in the axial direction. The length Hs of the illustrated spring entry allowable space 46 in the direction orthogonal to the axial direction is larger than the diameter of the coil spring 60. The axial length Ls of the spring entry allowance space 46 is set according to the natural length of the coil spring 60 and the like. Details of this point will be described later.

  The barrel portion 44 is formed in a substantially U-shaped cross section like the fixed portion 42 (see FIG. 5A), and the size thereof is smaller than the fixed portion 42. As shown in FIG. 6, the cable fixing member 40 is fixed to the optical cable 90 by caulking the barrel portion 44 to the end portion of the sheath 96. The caulking method of the cable fixing member 40 is not particularly limited. In the present embodiment, as shown in the drawing, a configuration is adopted in which the barrel portion 44 is bent inward, and the tip of the barrel portion 44 is bitten into the center of the sheath 96. Further, as shown in FIG. 5, a protrusion 441 is formed on the inner surface of the barrel portion 44. When the barrel portion 44 is caulked, the protrusion 441 bites into the sheath 96, so that the connection strength of the cable fixing member 40 to the optical cable 90 is improved.

  The ferrule 50 is a member integrally formed of a synthetic resin material. As shown in FIGS. 1, 2, 7, and 8, a relatively narrow main body 52 and a relatively thick body are provided. The hook part 54 is provided. The ferrule 50 is housed in the housing body 22 such that the main body 52 is fitted into the width detail 222a (front end side) of the ferrule housing section 222, and the hook portion 54 is fitted into the wide width part 222b (rear end side). The ferrule 50 accommodated in this manner is slidable in the axial direction, but the hooking portion 54 is caught on the step portion of the ferrule accommodating portion 222 (the boundary between the width detail 222a and the width thick portion 222b). Does not move to the tip side.

  Further, the ferrule 50 is formed with two through holes 56 penetrating from the front end surface 52a to the rear end surface 54a. In each of the two through holes 56, one optical fiber 92 for transmission and reception of the optical cable 90 is fixed. Specifically, after the optical fiber 92 is inserted into each of the through holes 56, an adhesive is poured from an adhesive injection port 52 b formed on the side surface (upper surface) of the ferrule 50, so that the optical fiber 92 is connected to the ferrule 50. It is fixed to. After the optical fiber 92 is fixed in this way, the front end surface 52a of the ferrule 50 is subjected to mirror surface treatment in order to enhance the close contact with the front end surface 52a of the ferrule 50 accommodated in the mating connector and suppress increase in connection loss. Applied.

  Further, a spring locking portion 541 for locking the coil spring 60 is formed at the rear end of the ferrule 50 so as to protrude from the rear end surface 54a. The spring locking portion 541 is a cylindrical protrusion, and the outer diameter thereof is formed substantially the same as the inner diameter of the coil spring 60. Specifically, once the coil spring 60 is inserted into the spring locking portion 541, the coil spring 60 does not leave the rear end surface 54a of the ferrule 50 (light press-fit state) even if the rear end surface 54a is downward. It is formed in such an outer diameter.

  The coil spring 60 is inserted through the optical fiber 92 of the optical cable 90. Specifically, after fixing the cable fixing member 40 to the end portion of the sheath 96 of the optical cable 90, the coil spring 60 is inserted into the two optical fibers 92. Thereafter, since the tip of the optical fiber 92 is fixed to the ferrule 50, the coil spring 60 is positioned between the cable fixing member 40 and the ferrule 50. FIGS. 7 and 8 show an external perspective view and a cross-sectional view of an assembly including the optical cable 90, the cable fixing member 40, the ferrule 50, and the coil spring 60. FIG. A state (b) in which the assembly is incorporated in the housing main body 22 of the male connector 20 is shown together with the assembly (a). In the present embodiment, since the two optical fibers 92 included in the optical cable 90 are fixed to the common ferrule 50, the number of the coil springs 60 that urge the ferrule 50 is one. If one ferrule 50 is used for one optical fiber 92, the ferrule 50 that urges each ferrule 50 toward the tip side is necessary. In that case, the coil spring 60 is inserted into each optical fiber 92.

  As shown in FIG. 7, the natural length Lc of the coil spring 60 is formed to be longer than the axial length Lh of the coil spring accommodating portion 224 formed in the housing body 22. Therefore, when the coil spring 60 is accommodated in the coil spring accommodating portion 224, the coil spring 60 is in a compressed state, and the ferrule 50 is urged toward the distal end side with a force for returning to the original state.

  8, the natural length Lc of the coil spring 60 is equal to the length Ld from the rear end surface 54a of the ferrule 50 to the front end surface of the fixing portion 42 of the cable fixing member 40 in the axial direction. A length shorter than the length Ls of the spring entry allowance space 46 (dotted cross-hatching region shown in FIG. 8) provided inside the fixing portion 42 of the fixing member 40, that is, a relationship of “Lc ≦ Ld + Ls” is established. Is set to With this setting, the coil spring 60 is not contracted before the cable fixing member 40, the ferrule 50, and the coil spring 60 are housed in the housing body 22. The biasing force does not act on the ferrule 50.

  On the other hand, the female connector 30 has a housing body 32 and a housing cover 34, similar to the male connector 20. The ferrule housing part 322, the coil spring housing part 324, the fixing member housing part 326, and the hood part 328 are also formed in the housing body 32 of the female connector 30 shown in FIG. Has been. The cable fixing member 40, the ferrule 50, and the coil spring 60 having the same structure as that applied to the male connector 20 can also be applied to the female connector 30. Further, the housing body 32 is provided with a ferrule housing portion 322, a coil spring housing portion 324, and a fixing member housing portion 326 having a predetermined shape, and a housing cover 34 is attached to the notched portion of the housing body 32. (The four locking holes 342 provided in the housing cover 34 are fixedly attached to the four locking projections 329 provided in the housing main body 32), and the openings of the housing portions are covered. Since the point and the point 52a of the accommodated ferrule 50 are protected by the hood portion 328 are the same as those of the male connector 20, description thereof is omitted.

  As shown in FIG. 2, the male connector 20 and the female connector 30 having such a configuration have a fitting protrusion 227 provided on the housing main body 22 of the male connector 20, and the housing main body 32 of the female connector 30. It engages by being engaged with the fitting hole 327 formed in this. By fitting the two, the front end surfaces 52a of the ferrule 50 biased to the front end side by the coil spring 60 are abutted with each other, and the optical fiber 92 of the optical cable 90 is optically connected.

  Next, a method for assembling the optical cable connector 1 and the optical cable 90 will be described in detail although partially overlapping with the above description. In this embodiment, since there is no difference in the basic configuration of the male connector 20 and the female connector 30, a method for assembling the male connector 20 and the optical cable 90 will be described.

  The assembly method of the optical cable connector 1 (male connector 20) and the optical cable 90 according to the present embodiment includes a cable fixing member fixing step, a coil spring insertion step, a ferrule fixing step, a coil spring locking step, a ferrule and a coil. A spring housing step, a cable fixing step, and a housing cover attaching step;

  In the “cable fixing member fixing step”, first, the optical fiber 92 is exposed by peeling the sheath 96 of the optical cable 90 from the tip by a predetermined length. The tension member 94 exposed by the peeling of the sheath 96 is cut. Then, the cable fixing member 40 is fixed by caulking to the terminal portion of the sheath 96 on the peeled side. Specifically, the barrel portion 44 of the cable fixing member 40 is bent inward and fixed by being pierced into the sheath 96. Thereby, an assembly of the optical cable 90 and the cable fixing member 40 as shown in FIG. 6 is obtained. Note that the fixing by caulking is a common caulking device (for example, caulking device described in JP-A-2003-217784) including a crimper and an anvil, which is commonly used when caulking a crimp terminal to an electric wire. A caulking device can be applied.

  In the “coil spring insertion process”, the coil springs 60 are inserted from the tips of the two optical fibers 92 exposed. At this time, since the cable fixing member 40 is already fixed to the end portion of the sheath 96 in the “cable fixing member fixing step”, the coil spring 60 cannot be moved to the position where it is hooked on the sheath 96. That is, the coil spring 60 is always held while being caught by the optical fiber 92.

  In the “ferrule fixing step”, the ferrule 50 is fixed to the tips of the two optical fibers 92 through which the coil springs 60 are inserted. Specifically, first, the optical fiber 92 is inserted through the through hole 56 of the ferrule 50. Then, an adhesive is injected from the adhesive injection hole 52 b to fix the optical fiber 92 to the ferrule 50. The fixing position of the ferrule 50 is such that the natural length Lc of the coil spring 60 is the length Ld from the rear end surface 54a of the ferrule 50 to the front end surface of the fixing portion 42 of the cable fixing member 40 in the axial direction. It is a position that is shorter than the length Ls of the spring entry allowance space 46 provided inside the fixed portion 42 of 40, that is, the relationship of “Lc ≦ Ld + Ls” is established. When the optical fiber 92 is fixed to the ferrule 50 in this way, an assembly of the optical cable 90, the cable fixing member 40, the ferrule 50, and the coil spring 60 as shown in FIGS. 7A and 8 is obtained.

  If the ferrule 50 is fixed in such a position, the coil spring 60 inserted through the optical fiber 92 is in a natural length state, so that the biasing force does not act on the ferrule 50. That is, since the ferrule 50 is not biased to the tip side by the coil spring 60, the workability of the mirror surface treatment of the tip surface 52a of the ferrule 50 performed after the “ferrule fixing step” is improved.

  Further, in the assembling method according to the present embodiment, after the “ferrule fixing step”, the “coil spring” is configured to lock the coil spring 60 on the columnar spring locking portion 541 formed to protrude from the rear end surface 54a of the ferrule 50. "Locking step" is performed. As a result, the coil spring 60 inserted through the optical fiber 92 does not interfere with the assembly work such as the mirror finishing work on the tip surface of the ferrule 50. Further, since the load due to the weight of the coil spring 60 is not applied to the ultrafine optical fiber 92, the possibility of disconnection of the optical fiber 92 is reduced.

  In the “ferrule and coil spring housing step”, the ferrule 50 and the coil spring 60 are housed in the ferrule housing portion 222 and the coil spring housing portion 224 formed in the housing body 22. As shown in FIG. 7, the natural length Lc of the coil spring 60 is formed to be longer than the axial length Lh of the coil spring accommodating portion 224 formed in the housing body 22. When the spring 60 is accommodated in the coil spring accommodating portion 224, the ferrule 50 is biased toward the distal end side.

  In the “cable fixing step”, the fixing portion 42 of the cable fixing member 40 is fixed to the fixing member accommodating portion 226 formed in the housing main body 22. Specifically, the press-fitting part 421 provided in the fixing part 42 is press-fitted into a press-fitting hole 226 a formed on the bottom surface of the fixing member accommodating part 226. Thereby, as shown in FIG. 7B, the optical cable 90 is fixed to the housing body 22.

  In the “housing cover attaching step”, the housing cover 24 is attached to the notched portion of the housing main body 22. Thereby, the openings of the ferrule housing part 222, the coil spring housing part 224, and the fixing member housing part 226 formed in the housing body 22 are covered. Specifically, each of the four locking holes 242 provided in the housing cover 24 is attached to the four locking projections 229 provided in the housing main body 22.

  The assembly of the male connector 20 and the optical cable 90 is completed through the above steps. Since the female connector 30 and the optical cable 90 can be assembled in the same process, the description thereof is omitted. In this way, the assembly of the optical cable connector 1 and the optical cable 90 is completed.

  The configuration of the optical cable connector 1 and the method for assembling the optical cable connector 1 and the optical cable 90 according to one embodiment of the present invention have been described above. According to the optical cable connector 1, the following operational effects can be achieved.

  In the present embodiment, the fixing portion 42 of the cable fixing member 40 fixed to the terminal portion of the sheath 96 is fixed to the fixing member receiving portions 226 and 326 of the housing main bodies 22 and 32, so that the male connector 20 and the female connector 20. The optical cable 90 is securely fixed to the mold connector 30. Since the cable fixing member 40 can be fixed by caulking the barrel portion 44 to the end portion of the sheath 96, the cable fixing member 40 is easy to assemble and does not increase the work process.

  The male connector 20 and the female connector 30 are divided into housing bodies 22 and 32 and housing covers 24 and 34, and the housing bodies 22 and 34 include a ferrule housing portion in which the ferrule 50 is housed. 222, 322, coil spring accommodating portions 224, 324 in which the coil spring 60 is accommodated, and fixing member accommodating portions 226, 326 in which the terminal portions of the sheath 96 are accommodated are formed to open outward. Therefore, unlike the prior art, it is not necessary to advance the assembly after passing the connector housing through the optical cable in advance. That is, after the cable fixing member 40 is fixed to the sheath 96, the coil spring 60 is inserted into the optical fiber 92, and the optical fiber 92 is fixed to the ferrule 50 (the assembly shown in FIG. 7A). After being obtained), these members (assemblies) can be stored and fixed in the connector housing. Therefore, the assembly workability is greatly improved as compared with the case where the assembly is advanced in a state where the connector housing is passed through the optical cable in advance.

  Further, the fixing portion 42 of the cable fixing member 40 is formed in a substantially U-shaped cross section, and a spring entry allowing space 46 having a predetermined length that allows the coil spring 60 to enter is provided inside thereof. The spring entry allowance space 46 has a length obtained by adding a length Ld from the rear end face 54 a of the ferrule 50 to the tip end face of the cable fixing member 40 to the length Ls of the spring entry allowance space 46. The size is formed so as to be longer than the length Lc (in other words, the ferrule 50 is fixed at a position having such a relationship). Therefore, in a state before the ferrule 50 and the coil spring 60 are housed in the housing body 22, the urging force of the coil spring 60 does not act on the ferrule 50. That is, since the mirror surface processing operation of the front end surface 52a of the ferrule 50 can be performed in a state where the urging force of the coil spring 60 does not contribute to the ferrule 50, the assembling workability is further improved. Further, the spring entry allowing space 46 is provided inside the fixing portion 42 of the cable fixing member 40. In other words, in the present embodiment, by providing the fixed portion 42 and the spring entry allowance space 46 so as to overlap in the axial direction, an increase in the size of the connector in the axial direction due to the provision of the spring entry allowance space 46 is prevented. . Thus, by providing the spring entry allowance space 46 of a predetermined size inside the fixing portion 42 of the cable fixing member 40, the assembly workability can be greatly improved without increasing the size of the connector.

  If the spring locking portion 541 for locking the coil spring 60 is provided on the rear end surface 54 a of the ferrule 50, the coil spring 60 positioned between the cable fixing member 40 and the ferrule 50 is locked to the ferrule 50. I can leave it to you. Thereby, the coil spring 60 inserted through the optical fiber 92 does not interfere with the assembly work. Further, since the load due to the weight of the coil spring 60 is not applied to the ultrafine optical fiber 92, the possibility of the optical fiber 92 being disconnected is reduced.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

  For example, in the above-described embodiment, it has been described that each of the male connector 20 and the female connector 30 is a split connector including the housing main bodies 22 and 32 and the housing covers 24 and 34. It is also possible to adopt a configuration in which such a technical idea is adopted for only one of the 20 and the female connectors 30.

DESCRIPTION OF SYMBOLS 1 Optical cable connector 20 Male connector 22 Housing main body 222 Ferrule accommodating part 224 Coil spring accommodating part 226 Fixed member accommodating part 24 Housing cover 30 Female connector 32 Housing main body 322 Ferrule accommodating part 324 Coil spring accommodating part 326 Fixed member accommodating part 40 Cable Fixing member 42 Fixing part 44 Barrel part 46 Spring entry allowable space 50 Ferrule 52a Tip surface 541 Spring locking part 60 Coil spring 90 Optical cable 92 Optical fiber 96 Sheath

Claims (6)

An optical cable connector having a ferrule to which a terminal portion of an optical fiber exposed for a predetermined length from the tip of an optical cable in which an optical fiber is covered with a sheath is fixed, and a coil spring that biases the ferrule toward the tip,
A housing main body formed such that a ferrule housing portion for housing the ferrule, a coil spring housing portion for housing the coil spring, and a fixing member housing portion for housing a terminal portion of the sheath open outward. A connector housing having a housing cover that is attached to the housing body so as to cover the openings of the housing portions, a barrel portion that is crimped to a terminal portion of the sheath, and a distal end side of the barrel portion. A cable fixing member having a fixing portion fixed to the fixing member receiving portion ,
A spring entry allowing space for allowing the coil spring to enter is formed inside the fixing portion of the cable fixing member, and the natural length of the coil spring is determined from the rear end surface of the ferrule in the axial direction of the optical cable. An optical cable connector characterized by being shorter than a length obtained by adding the length of the spring entry allowance space to the length of the fixing portion of the fixing member to the tip end surface . The optical cable connector according to claim 1 , wherein the spring entry allowable space is provided inside a fixing portion of the cable fixing member formed in a substantially U-shaped cross section. 3. The optical cable connector according to claim 1, wherein a spring locking portion for locking the coil spring is provided at a rear end of the ferrule. A cable fixing member having a barrel portion and a fixing portion provided on the distal end side from the barrel portion is exposed by peeling off the sheath of the optical cable having the optical fiber covered with the sheath by a predetermined length from the distal end. A cable fixing member fixing step for fixing the barrel portion to the optical cable by caulking the end portion of the sheath;
A coil spring insertion step of inserting a coil spring into the optical fiber exposed on the tip side of the optical cable;
A ferrule fixing step of fixing a ferrule to a tip portion of the optical fiber through which the coil spring is inserted;
The ferrule is biased toward the distal end side of the ferrule in the ferrule housing portion formed in the housing body so as to open outward, and the coil spring housing portion formed in the housing body so as to open outward as well. A ferrule that accommodates the coil spring so as to be in a closed state and a coil spring housing step;
A cable fixing step of fixing a fixing portion of the cable fixing member fixed to the optical cable to a fixing member accommodating portion formed in the housing body so as to open outward;
A housing cover on the housing body so as to cover an opening of the ferrule housing portion in which the ferrule is housed, the coil spring housing portion in which the coil spring is housed, and the fixing member housing portion to which the fixing portion of the cable fixing member is fixed. A housing cover deposition process for depositing;
Only including,
A spring entry allowance space that allows entry of the coil spring is formed inside the fixing portion of the cable fixing member, and in the ferrule fixing step, the natural length of the coil spring is in the axial direction of the optical cable. An assembly of an optical cable connector and an optical cable , wherein the ferrule is fixed at a position shorter than a length obtained by adding a length of the entry allowable space to a length from a rear end surface of the ferrule to a front end of the cable fixing member. Method. 5. The method of assembling an optical cable connector and an optical cable according to claim 4 , wherein the spring entry allowable space is provided inside a fixing portion of the cable fixing member formed in a substantially U-shaped cross section. A spring locking portion for locking the coil spring is provided at the rear end of the ferrule, and includes a coil spring locking step for locking the coil spring to the coil spring locking portion after the ferrule fixing step. 6. The method of assembling an optical cable connector and an optical cable according to claim 4 or 5 .

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