JPH08262271A - Dustproof cap for optical fiber connector - Google Patents

Abstract

PURPOSE: To enhance dustproofness, to eliminate the need for cleaning at the time of connection after preservation and make a dustproof cap usable for multiplex adapters as well by providing this cap with a main body to be inserted into an adapter from its opposite side and a recessed part formed at the front end of the main body. CONSTITUTION: This dustproof cap 40 has a cap body 41 approximately similar to a plug body and a slider member 42 which is completely identical with the slider. A front end contact surface 50 of a contact part 49 is formed as a slope fitting to the inclination at the front end face of a ferrule. The recessed part 51 positioned between both hole parts 48 is formed at the contact surface 50. The recessed part 51 parts the dummy ferrule 45 from optical fiber ends 4 and is therefore formed to such a position and size that the optical fiber ends 4 are integrally housed. The front end contact surface 50 is brought into surface- to-surface contact with the front end face of the ferrule without contact with the optical fiber ends at all when the dustproof cap 40 is inserted. The dustproof cap is so formed that the cap body 41 is inserted into the insertion port of the adapter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dustproof cap for protecting a push-on fastening type multi-fiber optical fiber connector used for optical communication.

[0002]

2. Description of the Related Art A push-on fastening type multi-fiber optical fiber connector is generally constructed as shown in FIG. As shown, the optical fiber connector 1 includes a plug body 2 and
The slider 3 is attached to the outer peripheral portion thereof. An optical fiber ferrule 6 is housed in the plug body 2,
A plurality of optical fibers are exposed flush with the front end surface of the ferrule 6 to form an optical fiber end 4. The slider 3 is attached to the plug body 2 via an elastic body (not shown), and is normally positioned on the front end side in the longitudinal direction of the plug body 2 due to its urging force.

The connectors 1 are connected to each other via an adapter 10. This adapter 10 is multiple (4 in the illustrated example
The adapters 10 are arranged vertically on a common body a. Adapter 10 formed in a tubular shape
Inside the connector 1 from the one side and the other side, respectively.
Is inserted and the front end surfaces of the ferrules 6 are butted against each other in the adapter 10 so that the optical fiber ends 4 are brought into contact with each other without displacement and connected. Here, a claw 21a that engages with the groove of the plug body 2 (usually hidden by the slider 3) is provided on the inner peripheral portion of the adapter 10, and the claw 21a engages with the groove to allow the connector Lock 1 In the process of inserting the connector 1, first the claw 2
1a abuts the slider 3, and moves the slider 3 to the base end side against the biasing force of the elastic body. And the nail 21a
After engaging in the groove, the slider 3 returns to its original position and covers the claw 21a to maintain the engaged state and prevent the connector 1 from coming off.

The connector may be stored for a long period of time while being inserted into one side of the adapter. In this case, the dustproof cap shown in FIGS. Protect the fiber end. First, in FIG. 8, the connector 1 is inserted from one side into a single type adapter 10 which is not multiple. The dustproof cap b is covered on the other side from the outside, and after mounting, the other side is closed as shown in FIG. The dustproof cap b is made of rubber, and prevents dust and the like from entering the connector 1 after being covered, and protects the optical fiber end 4 on the end face of the ferrule 6.

[0005]

By the way, such a dustproof cap is mounted on the other side of the adapter to protect the end of the optical fiber when the connector is inserted only on one side and the other side is vacant. It is a thing.

However, the conventional dustproof cap described above has the following problems.

The hermeticity is not always good, and dust or the like may enter when stored for a long time. This causes dust and the like to adhere to the end of the optical fiber, which requires cleaning when connecting after storage.

In some of the multiple adapters described above, the connectors are inserted from the opposite side, but the remaining adapters may be inserted only on one side. In this case, the dustproof cap cannot be attached to the empty portion, and the optical fiber end cannot be protected.

Therefore, the present invention was devised in order to solve the above-mentioned problems, and its purpose is to improve dustproofness, eliminate the need for cleaning when connecting after storage, and also for a multiple adapter. An object is to provide a dustproof cap for an optical fiber connector that can be used.

[0010]

In order to achieve the above object, a dustproof cap for an optical fiber connector according to a first aspect of the present invention is provided with an optical fiber connector inserted from one side from an opposite side thereof. Body to be inserted,
A recess is formed at the tip of the main body and is separated from the optical fiber end of the optical fiber connector.

The present invention according to claim 2 is the same as claim 1
In the dustproof cap for an optical fiber connector described above, the tip has an abutting portion that comes into close contact with the tip of the ferrule around the optical fiber end.

The present invention according to claim 3 provides the invention according to claim 1.
Alternatively, in the dustproof cap for an optical fiber connector described in either one of the above, the recess is formed so as to cover the positioning pin protruding from the tip of the ferrule and the end of the optical fiber.

[0013]

According to the first aspect of the present invention, the main body is inserted into the adapter to close the adapter. And the recess is
The body is spaced from the optical fiber end so that it does not contact the optical fiber end.

According to the second aspect of the present invention, the contact portion is in close contact with the tip of the ferrule around the end of the optical fiber to block dust.

According to the present invention of claim 3, the recess is
It also covers the positioning pins to prevent contact with the end of the optical fiber.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

First, an optical fiber connector and an adapter into which the optical fiber connector is inserted (fastened) and detached will be described with reference to FIGS. 2, 3, 7, and 8. 2A is a cross-sectional plan view in a detached state, FIG. 2B is a vertical cross-sectional front view, FIG. 3A is a cross-sectional plan view in an inserted state, and FIG.
These are the same as the conventional ones, the parts that can be seen in appearance are shown in FIGS. 7 and 8, and the internal structure is shown in FIGS.
Please refer mainly to.

As shown in FIG. 7, the optical fiber connector 1
Has a plug body 2 extending in one direction and a slider 3 attached to the outer peripheral portion thereof. Plug body 2
Is a molded product made of resin or a plastic material, in which a tape fiber (or tape fiber cord) 5 having a plurality of optical fibers is embedded. Inside the plug body 2, the optical fiber ferrule 6 provided at the tip of the tape fiber 5 contains the optical fiber. The tip of this ferrule 6 is projected from the plug body 2, and the end face of each optical fiber, that is, the fiber end 4 is exposed flush with the end face 7. The optical fiber end 4 has a ferrule 6
Are arranged side by side along the width direction.

The plug body 2 comprises an insertion portion 8 on the distal end side in the longitudinal direction and a hand-holding portion 9 on the proximal end side in the longitudinal direction. The slider 3 is attached at an intermediate position of the insertion portion 8 and is slidable along the longitudinal direction of the plug body 2 by a predetermined stroke.

As shown in FIG. 2, the optical fiber connector 1
The insertion part 8 is formed in a wide rectangular tube shape, and the tape fiber 5 and the ferrule 6 are accommodated in the hole 11 along the longitudinal direction. The ferrule 6 is slidable in the hole 11, and the step 12 of the ferrule 6 contacts the step 13 of the hole 11 to restrict movement in the distal direction. Ferrule 6
The guide pins 14 are inserted into both widthwise end portions of the guide pins 14 and these guide pins 14 are spacers (pin clamps).
It is integrated into 15. The spacer 15 is fitted to the base end portion 16 of the ferrule 6 and fills the gap with the inner wall of the hole 11. A pressing spring 17 composed of a rectangular or elliptical coil spring is provided on the outside of the tape fiber 5, and the tip surface of the ferrule 6 abuts on the tip surface of the mating ferrule (not shown) when the connectors are connected to each other. At that time, the ferrule 6 is compressed and deformed by the reaction force, and plays a role of pressing the ferrule 6 against the other party through the spacer 15. The movement of the ferrule 6 toward the base end side is restricted by a fixed sleeve 18 provided on the outer peripheral side of the pressing spring 17.

Referring also to FIG. 7, in the outer peripheral portion of the insertion portion 8,
Guide grooves 19 are formed on both side portions in the width direction, and convex portions 20 are formed on the upper side portion in the height direction along the longitudinal direction. These are for guiding the insertion / removal of the insertion portion 8 into / from the adapter 10, and therefore, even in the inner peripheral portion of the adapter 10,
A claw 21a for sliding the guide groove 19 and a guide groove 21b for sliding the convex portion 20 are formed. The guide groove 19 of the insertion portion 8 is partitioned by a riding portion 22 having a substantially trapezoidal cross section provided in the middle of the guide groove 19.
A hole-shaped groove 23 is formed at the base end of the. The convex portion 20 and the guide groove 21b are provided only on the upper side to prevent the connector 1 from being inverted and inserted.

The slider 3 surrounds the insertion portion 8 from the outside, and has slider pushing springs 24 extending to the insertion portion 8 on the inner surface portions on both sides in the width direction thereof. Slider push spring 24
Is composed of a large number of leaf springs that are attached at an angle, and biases the slider 3 toward the tip side. The slider 3 urged by this is arranged so that the upper and lower step portions 25 contact the convex portion 20 and the lower protruding portion 26 of the insertion portion 8 and stop. At this time, the tip projection 3a of the slider 3 covers the hole-shaped groove 23.

As shown in FIG. 7, on the outer peripheral portion of the slider 3, annular convex portions 27 are formed around the slider 3 at equal intervals in the longitudinal direction. This improves the adhesion to the slider 3 of the hand,
It functions to facilitate the movement of the slider 3 when it is detached.

On the other hand, as shown in FIG.
Has a substantially rectangular tubular shape whose outer shape is larger than that of the slider 3, and allows the optical fiber connector 1 to be inserted from the insertion port 10a on the opposite side. However, in this embodiment, the connector 1 is inserted into the insertion opening 10a on one side, and the dustproof cap 40 according to the present invention is inserted into the insertion opening 10a on the other side. The dustproof cap 40 will be described later in detail. The adapter 10 is the one shown in FIG. 8 (FIG. 9) from which the mounting flange portion c is removed.
The adapter 10 has a symmetrical structure with the middle position in the longitudinal direction as a boundary.

The adapter 10 is formed by integrating a pair of adapter halves 29 made of resin, plastic material or the like in opposite directions, and each of the adapter halves 29 has the claw 21a and the guide groove 21b. Have. Nail 21
The a is formed at the tip of the adapter half body 29 so as to project inward while forming a gap 31. The cross-sectional shape of the claw 21a is
It has a substantially trapezoidal shape that fits into the hole-shaped groove 23 of the plug body 2. On the base end side of the claw 21a, the split portion 30 is formed by being separated by a predetermined distance in the longitudinal direction, and the leaf spring portion 32 of the adapter half body 29 is elastically deformed by the split portion 30.
Allow movement of 1a.

Here, how the connector 1 is fastened and unfastened from the adapter 10 will be described. First, at the time of fastening, the tip of the insertion portion 8 of the plug body 2 is inserted into one side of the adapter 10. This insertion is performed by holding the hand holding portion 9 by hand. When the insertion is continued, the claw 21a rides on the riding portion 22 and abuts on the tip end protruding portion 3a of the slider 3 to move the slider 3 to the base end side or rearward. Further, as shown in FIG.
When a is set in the hole groove 23, the slider 3 is pushed by the spring 2.
The urging force of No. 4 returns to the original position, and the tip end protruding portion 3a becomes the claw 21.
The claw 21 a is held in the hole-shaped groove 23 by covering the outer side of a. This completes the fastening and the connector 1 becomes the adapter 1
Fully locked to 0. At this time, the tip protrusion 3
The a enters the gap 31 and is covered by the outer cylinder member 30. In this way, push-on fastening is performed only by pushing the connector 1.

If another connector (not shown) is inserted into the other side of the adapter 10, the connectors are connected to each other. Here, the tip surface 7 of the ferrule 6 is an inclined surface in which the lower side is pulled toward the base end side as compared with the upper side. Therefore, the front end surface of the ferrule of the other connector is an opposite inclined surface that comes into surface contact with this. As a result, the front end surfaces of the optical fibers come into surface contact with each other, and the optical fiber ends 4 come into complete contact with each other. The ferrule of another connector is provided with a hole to replace the guide pin 14, and insertion of the pin 14 into the hole achieves more accurate positioning. The ferrules are pressed against each other by the action of the pressing spring 17.

On the other hand, when detaching, the slider 3 is held by hand and pulled to the base end side. In this way, the tip protrusion 3a
The claw 21a is released from the holding state, and by continuing to pull the claw 21a, the claw 21a comes out of the hole-like groove 23, and the connector 1 is detached. At this time, the stopper 33 (see FIG. 7) formed on the insertion portion 8 restricts the movement of the slider 3 and transmits the pulling force thereof to the plug body 2. In this way, even when detached, pull-off detachment is achieved by only pulling the slider 3.

When the connector 1 fastened to one side of the adapter 10 is stored for a long period of time, the dustproof cap 40 is inserted into the other side to protect the connector 1.

FIG. 1 is a perspective view showing a dustproof cap for an optical fiber connector according to the present invention, and FIGS. 2 and 3 are sectional views showing a detached and fastened (inserted) state, respectively.

As can be seen from the figure, the dustproof cap 40 has substantially the same structure as the connector 1 and is constructed by using the same parts. That is, the dustproof cap 40 includes a cap body 41 that is substantially the same as the plug body 2,
It has a slider member 42 which is completely the same as the slider 3.
The base end 41 a of the cap body 41 is closed because the tape fiber 5 is not inserted. Cap body 4
A hole portion 44 having the same shape as the hole 11 is formed inside the insertion portion 43 of No. 1, and the dummy ferrule 45 that projects from the cap body 41 and forms the tip 41b thereof is formed inside the hole portion 44.
And a spacer member 46 located on the base end side thereof are slidably accommodated. The dummy ferrule 45 is the step 4
7, the spacer member 46 abuts on the base end surface of the step portion 47. The dummy ferrule 45 has holes 48 at both ends in the width direction for inserting the guide pins 14 of the ferrule 6 therein. The tip of the dummy ferrule 45 protruding from the cap body 41 forms an abutting portion 49 that abuts or is in close contact with the ferrule tip surface 7 around the optical fiber end 4. The pressing spring 17 is diverted to the outside of the fiber pseudo portion 48 of the spacer member 46. The other parts or the same parts are given the same reference numerals and the description thereof will be omitted.

The tip end contact surface 50 of the contact portion 49 is an inclined surface that conforms to the inclination of the ferrule front end surface 7, that is, the lower portion protrudes toward the distal end side as compared with the upper portion. And contact surface 5
At 0, a concave portion 51 located between both hole portions 48 is formed. The recess 51 is formed in such a position and size as to collectively house the optical fiber ends 4 so as to separate the dummy ferrule 45 from the optical fiber ends 4, and here, it is formed in a rectangular shape which is long in the width direction and abuts. It is formed to a depth equal to the protruding length of the contact portion 49. As a result, the contact portion 49 is formed in a frame shape that collectively surrounds the optical fiber end 4. Then, as shown in FIG. 3, when the dustproof cap 40 is inserted,
The tip abutting surface 50 makes surface contact with the ferrule tip surface 7 without making any contact with the optical fiber end 4. This prevents the optical fiber end 4 from being scratched. These surfaces 50,
The 7 springs are pressed against each other by the action of the pressing spring 17 to be in close contact with each other. Here, vertical surfaces 52 and 53 are formed above the ferrule tip surface 7 and the tip contact surface 50, respectively. In the present embodiment, these vertical surfaces 52 and 53 are also in close contact with each other. The 52 and 53 may be slightly separated from each other to enhance the adhesion between the ferrule tip surface 7 and the tip contact surface 50.

The dustproof cap 40 having the above structure has the following advantages.

First, since the cap body 41 is inserted into the insertion opening 10a of the adapter 10, the insertion opening 10a can be closed. Although most of the dust is blocked by this, even if it is stored for a long period of time, fine dust may still enter. However, in the dustproof cap 40, since the abutting portion 49 abuts the ferrule tip surface 7 around the optical fiber end 4, such fine dust is completely blocked, and the ferrule tip surface 7 and particularly the optical fiber end 4 is blocked. Can be completely prevented. Also, moisture and the like can be blocked, and the optical fiber end 4 can be prevented from becoming dirty. As described above, the dustproof property and the hermeticity are extremely good, the optical fiber end 4 can be surely protected during storage, and cleaning can be unnecessary when connecting after storage. The connection after storage can be immediately made by removing the dustproof cap 40.

As a second advantage, the dustproof cap 40 can be attached to an empty portion of the multiple adapter. This is not something that is worn from the outside as in the past,
This is because it is configured to be inserted inside the adapter.

As a further advantage, the dustproof cap 40
Since the connector 1 is configured in the same manner as the connector 1 and parts are diverted, the manufacturing cost can be greatly reduced. For example,
The cap body 41 can be manufactured by partially modifying the mold for manufacturing the plug body 2 (closing the base end portion 41a), and can be used as it is for the slider member 42.

Since the slider member 42 is provided,
Push-on engagement / pull-off disengagement, which is the same as the connector 1, is possible, and the advantages such as ease of engagement / disengagement can be inherited. And the slider member 42
However, since the dustproof cap 40 is securely locked at the time of insertion, it can be prevented from coming off during vibration or impact. Further, at the time of fastening, since the tip end protruding portion 42a of the slider member 42 enters the gap 31 of the adapter 10, the dustproof property can be further improved.

Next, a modified embodiment will be described.

As shown in FIGS. 4, 5 and 6, in this modified embodiment, the structure of the cap body 54 is different from that of the above embodiment. The cap body 54 has the hole 4
4 is not formed, but is solidly formed, and an abutting portion 55 is integrally formed at its tip 54a. The contact portion 55 is formed in a rectangular frame shape having a size along the outermost peripheral edge position of the tip portion of the connector 1, that is, the tip surface of the plug body 2, and the tip surface 56 of the contact portion 55 is the plug body 2. It is designed to be in surface contact or close contact with the entire tip surface of the. The inside of the contact portion 49 is a rectangular recess 57. The recess 57 has a larger width, height, and depth than those of the above-described embodiment, and the width and height can accommodate the ferrule 6. And the depth is set so as not to abut the guide pin 14. Therefore, the recess 57 is formed so as to cover the pin 14 and the optical fiber end 4. In addition, like the above,
The slider member 42 is biased and attached by the slider pressing spring 24, and the dummy ferrule 45 and the like are not provided.

With this, the same effect as the above can be exhibited, but in the case of the present embodiment, the concave portion 57 has the pin 14 in particular.
Since it also covers the above, there is an advantage that the positioning by the pin 14 as in the above embodiment is not necessary and the insertion can be easily performed. Further, since it is not in contact with the ferrule tip surface 7, the contact portion 55
Since it is not necessary to make the tip end surface 56 of the sloping surface a surface perpendicular to the longitudinal direction, there is an advantage that manufacturing and processing are easy. Moreover, since the number of parts is reduced, there are advantages that the structure and assembly are simplified and the manufacturing cost can be reduced.

The dust-proof cap according to the above-mentioned embodiment was actually manufactured, and the connector was mounted on one side of the adapter, and the dust-proof cap was inserted on the other side. Even without cleaning the tip surface, low loss connection with connection loss within 1 dB was possible.
For comparison, a conventional rubber dustproof cap was also tested, but it was impossible to achieve a low loss connection of 3 dB at maximum without cleaning. Thus, such a dustproof cap allows a low loss connection without cleaning.

The present invention is not limited to the above embodiment and can be implemented in various modes. For example, in the above embodiment, the slider member may be omitted, and the structure may be simplified to reduce the cost. However, in this case, the dustproof cap may easily come off due to vibration or the like. INDUSTRIAL APPLICABILITY The present invention is applicable to all types of optical communication and optical interconnects that perform optical signal transmission inside and outside a device.

[0043]

The present invention exhibits the following excellent effects.

(1) According to the present invention described in claim 1, it can be used for a multiple adapter.

(2) According to the present invention as set forth in claim 2, the dustproof property can be improved and cleaning can be made unnecessary at the time of connection after storage.

(3) According to the third aspect of the present invention, the positioning by the pin is unnecessary and the insertion can be facilitated.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a dustproof cap for an optical fiber connector according to the present invention.

2A and 2B show detached states of an optical fiber connector, an adapter, and a dustproof cap, FIG. 2A is a cross-sectional plan view, and FIG. 2B is a vertical sectional front view.

3 shows the insertion state of FIG. 2, (a) is a cross-sectional plan view,
(B) is a vertical sectional front view.

FIG. 4 is a perspective view showing a modified embodiment of the dustproof cap for an optical fiber connector according to the present invention.

5A and 5B show a detached state of an optical fiber connector, an adapter and a dustproof cap, FIG. 5A is a transverse plan view, and FIG. 5B is a vertical sectional front view.

6 shows the insertion state of FIG. 5, (a) is a transverse plan view,
(B) is a vertical sectional front view.

FIG. 7 is a perspective view showing an optical fiber connector and a multiple adapter.

FIG. 8 is a perspective view showing a detached state of a conventional dustproof cap.

9 is a perspective view showing an inserted state of FIG.

[Explanation of symbols]

 1 Optical Fiber Connector 4 Optical Fiber End 7 Ferrule Tip Surface 10 Adapter 14 Guide Pin 40 Optical Fiber Connector Dust-Proof Cap 41, 54 Cap Body 41b, 54a Tip 49, 55 Abutment 51, 57 Recess

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Nishiyama 5-5-23 Osaki, Shinagawa-ku, Tokyo Hirose Electric Co., Ltd.

Claims (3)

[Claims] 1. A main body to be inserted from the opposite side into an adapter into which an optical fiber connector is inserted from one side, and a recess formed at the tip of the main body for separating from the optical fiber end of the optical fiber connector. A dustproof cap for an optical fiber connector, which is provided with. 2. The dustproof cap for an optical fiber connector according to claim 1, wherein the tip has an abutting portion that comes into close contact with the tip of the ferrule around the end of the optical fiber. 3. The dustproof cap for an optical fiber connector according to claim 1, wherein the recess is formed so as to cover the positioning pin protruding from the ferrule tip and the optical fiber end.