JPS6261923B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical fiber connector used in optical communications.

The fastening methods for optical fiber connectors can be roughly classified into rotary fastening methods such as screw fastening and non-rotary fastening methods. Non-rotating fastening methods are superior to rotary fastening methods in terms of operability, vibration resistance, etc., and are expected to be widely used in the future as a simple fastening method not only for electrical connectors but also for optical fiber connectors. Ru.

FIG. 1 shows one row of optical connector plugs used in a conventional non-rotating fastening method. In the figure, the tip of the optical fiber cord 5 has a cylindrical ferrule 3.
is fixed. On the outside of this ferrule is the spring 4
and a spring stopper 11 are arranged. The stopper 11 is glued or screwed around the ferrule. The spring 4 abuts the stopper 11 on one side and the inner wall of the housing 1 on the other end. Housing 1 has ferrule 3 inside
It accommodates the tip of the optical fiber cord 5 and has a rectangular outer diameter. Furthermore, grooves 1c, 1c', 1d, and 1d' are formed on the two outer side surfaces of the housing 1. Housing 2 is in contact with the outside of housing 1,
Cantilever beams 2a, 2a' are formed at the rear end. Furthermore, protrusions 2b and 2b' that engage with the grooves 1d and 1d' are formed at their tips, thereby preventing movement of the housing 2 in the optical axis direction. Cantilever beams 1b and 1b' protrude from the left side of the housing 1,
Protrusions 1a and 1a' are formed at the tips of the beams.

When connecting the plug to the adapter, while inserting the tip of the ferrule 3 into the adapter 6 as shown in FIG.
The protrusions 1a and 1a' are fitted into the grooves 6a of the plug. Next, as shown in FIG.
1d' and move the housing 2 in the direction of the arrow A, the protrusions 2b and 2b' are fitted into the grooves 1c and 1c' on the outside of the housing 1, respectively. Thereby, the connection part is pressed down by the housing 2 from the outside.

However, in the above conventional example, when the plug is connected to the adapter, the tip of the housing 2 on the adapter side only covers the outside of the cantilever beams 1c and 1c'.
Do not touch the adapter 6. As a result, the plug is easily deformed when bent in a direction perpendicular to the optical axis. In order to prevent this deformation, it is conceivable to increase the length of the housing 2 in the direction toward the adapter so that the tip of the housing 2 on the adapter side comes into contact with the flange of the adapter 6 during connection. However, if the length is increased in this way, the cantilever beams 1b, 1b' of the housing 1 are pressed down from the outside by the housing 2 during connection, making it difficult to expand the cantilever beams. It is also conceivable to increase the length of the contact portion between the housing 1 and the housing 2 in FIG. 1, but this would result in an increase in the size of the plug. Furthermore, cantilever beams 2a, 2
Since a' is largely deformed in the direction of the arrow B shown in FIG. 3, there is a drawback that the cantilever beam 2a is easily damaged. Furthermore, since the outside of the housing 2 is grabbed and pressed during the fastening operation, there is also a drawback that the housing 2 becomes difficult to slide on the outside of the housing 1.

An object of the present invention is to provide an optical fiber connector that has a large fastening force between a plug and an adapter, is easy to connect and disconnect, and has high durability against external forces such as bending of the plug.

According to the present invention, a housing that accommodates a ferrule with an optical fiber fixed on the central axis, a spring coaxially arranged on the outer periphery of the ferrule, and a member for preventing the spring from coming off is fitted into the adapter. In the optical fiber connector to be connected, the housing includes a first cantilever beam that protrudes along a direction parallel to the central axis of the ferrule and has a protrusion extending in the central axis direction at the tip thereof, and a first cantilever beam formed on a part of the outer periphery. a first housing having a groove, a hollow member slidably engaged with the first housing, a pair of second cantilevers extending from an inner wall of the hollow member parallel to the inner wall of the hollow member; a second housing having a protrusion protruding in the direction of the central axis at the tip of a second cantilever; the adapter has a hollow part in its center that receives the ferrule; a fitting groove for locking a protrusion of a support beam, the ferrule is fitted in the hollow part of the adapter, the protrusion of the first cantilever is fitted in the fitting groove, and the second An optical fiber connector is obtained in which the housing is slid toward the adapter and the protrusion of the second cantilever is fitted into the groove of the first housing for connection.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIGS. 4a and 4b show an embodiment of the present invention, where a is a side sectional view and b is a front view of the plug.

In the figure, a cylindrical sleeve 13 is attached to the outer sheath of the tip portion of the optical fiber cord 5 and fixed with adhesive. A rubber pipe 14 is arranged around the outer periphery of the metal sleeve 13 and the optical fiber cord 5, and absorbs the tension applied to the optical fiber cord. The inner diameter of the distal end of the metal sleeve 13 is larger than the inner diameter of the portion bonded to the optical fiber cord, and a thread is formed on the inner wall of the large inner diameter. A cylindrical ferrule 9 is inserted into the tip of the optical fiber cord from which the outer sheath has been removed, and the ferrule is inserted into the metal sleeve 13.
Kevlar (tension member) 5a of the optical fiber cord 5 and the optical fiber coating 5
b and the side surface of the optical fiber wire 5c with an adhesive or resin. The optical fiber wire 5c is located on the central axis of the ferrule 9.

The ferrule 9 is housed in a first plastic housing 7, and a spring 10 is arranged between the housing 7 and the ferrule 9;
Movement is restricted by a ring-shaped set screw 12 via a metal stopper 11 having a square outer diameter and a pair of protrusions on opposite sides. Stoppa 11
The inner diameter of the stopper is square, and the outer diameter of the cylindrical ferrule 9 in contact with the inner diameter of the stopper is also square, thereby preventing rotation of the cylindrical ferrule 9.
The first housing 7 has a circular inner side and a rectangular outer shape in the A-A' cross section, and has a pair of cantilever beams 7 facing each other parallel to each other beyond the region in contact with the spring 10.
a, 7a'. Protrusions 7b and 7b' are formed at the tips of the cantilevers, respectively, in the direction of the central axis of the fiber. Openings 7d, 7d' are provided at the center of the cantilever beams 7a, 7a'.
The protrusion of the stopper 11 is located at d'. opening 7
Grooves 7c and 7c' are formed adjacent to grooves d and 7d', respectively. The first housing containing the ferrule etc. is further housed in a second plastic housing 8. The second housing 8 has a rectangular cross section both inside and outside on the left side of the line B-B', and on the right side of the line B-B' has a pair of cantilevers 8a and 8a' extending parallel to each other and facing each other. A cross section that continues directly to the left side of the second housing consists of a rectangular portion that is larger than the left side portion both on the inside and outside. Protrusions 8b, 8b' are formed at the tips of the cantilevers 8a, 8a' in the direction of the central axis of the fiber. The inner wall of the housing 8 can slide against the outer wall of the first housing, in particular its cantilevers 7a, 7a'.

FIG. 5 is a side view, partially in cross section, of the plug shown in FIG. 4 connected to the adapter.

The adapter 6 has a hollow hole on its central axis into which the cylindrical ferrule 9 is inserted, and cantilevers 7a and 7 of the plug.
Grooves 6a, 6 that fit into protrusions 7b, 7b' at the tip of a'
a′ is formed, and the outside is rectangular. Also, a rectangular outer surface 7 inserted into the second housing 8
b, which prevents the housing 8 from rotating when the plug is inserted. Further, the tip of the housing 8 is in contact with the flange of the adapter 6, and the protrusions 8b, 8b' at the tips of the cantilevers 8a, 8a' are fitted and locked in the grooves 7c, 7c', and the optical axis Directional movement is restricted. The cantilever beams 7a, 7a' of the housing 7 are held at their tips between the housing 8 and the grooves 6a, 6a' of the adapter 6.

The method of connecting the plug to the adapter is as shown in FIG.
7b' into the grooves 6a, 6a' of the adapter 6, then move the housing 8 in the direction of the arrow as shown in FIG.
Slide the outer periphery of the housing 7 until the grooves 7c, 7c' of the housing 7 fit into the grooves 7c, 7c' of the housing 7. In this state, the protrusions 7b, 7b' of the cantilevers 7a, 7a' are pressed inward by the housing 8, and the protrusions 8b, 8 of the cantilevers 8a, 8a' of the housing 8 are pressed inward by the housing 8.
b' fits into the grooves 7c, 7c' of the housing 7. Therefore, the housing 8 will not move due to vibration or impact, and the connection will not become incomplete.

According to the above embodiment, since the cantilevers 8a, 8a' having the protrusions 8b, 8b' for fixing the housing 8 to the housing 7 are provided inside the housing 8, the protrusions 8b, 8b' can be fixed to the housing 7. Deformation of the cantilever beams 8a, 8a' when fitting into the groove 7c is restricted, and the cantilever beams are difficult to break. In addition, when sliding the outside of the housing 7 toward the tip of the plug while grasping the outside of the housing 8 in FIG. I won't join. Therefore, the housing 8 can easily slide, improving the connection workability. Furthermore, at the time of connection, the tip of the housing 8 fits into the adapter 6, so the connecting part between the plug and the adapter is firmly held by the housing 8, and the housing 8 moves in response to an external force in the direction of the central axis of the plug. Never. Therefore, there is almost no external force applied to the ferrule 9 due to bending, and the ferrule is unlikely to be damaged.

[Brief explanation of the drawing]

Figure 1 is a side view of a plug of an optical fiber connector with a conventional non-rotating fastening mechanism, Figures 2 and 3
The figure is a side view showing the method of fastening the plug shown in FIG. 1 to the adapter, FIGS. 6 is a plan view showing a partial sectional view of the optical connector according to the present invention, and FIGS. 6a and 6b are side views showing a method of fastening the optical connector in FIG. 5. 1, 2, 7, 8... Housing, 3, 9... Ferrule, 4, 10... Spring, 5... Fiber cord, 6... Adapter, 11... Stopper, 12
...Natsuto, 13...sleeve, 14...rubber holder.

Claims (1)

[Scope of Claims] 1. An optical fiber connector having an optical fiber plug and an adapter for receiving the optical fiber plug, wherein the optical fiber plug includes: a ferrule with an optical fiber fixed on a central axis; and a ferrule on the outer periphery of the ferrule. a spring disposed coaxially; a fall-off prevention member for preventing the spring from coming off from the outer periphery of the ferrule; and a spring that accommodates the ferrule, the spring, and the fall-off prevention member, and faces parallel to the central axis of the ferrule. a first housing having a pair of first cantilever beams extending in the direction of the center axis, a projection protruding in the direction of the central axis at the tip of the first cantilever beam, and a groove formed in a part of the outer periphery; A hollow member slidably engaged with the outer periphery of the first housing, a pair of second cantilevers extending from the inner wall of the hollow member in parallel to the inner wall, and a tip of the second cantilever. the adapter includes a second housing having a protrusion protruding in the direction of the central axis and an extension portion extending to form a double structure with the second cantilever; and a pair of mutually opposing fitting grooves provided on the outer periphery and locking the protrusion of the first cantilever, the ferrule is placed in the hollow part of the adapter, and the ferrule is placed in the fitting groove. The second housing is moved forward until the projections of the first cantilever are engaged, and the second housing is slid toward the adapter until it covers the first cantilever, and the projection of the second cantilever is moved forward until the projection of the second cantilever is engaged with the second housing. An optical fiber connector that connects by fitting into the groove of the housing of No. 1.