JP3194357B2 - Optical fiber connector plug - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plug for an optical fiber connector used for an optical fiber connector for mechanically connecting a pair of optical fibers to each other.

[0002]

2. Description of the Related Art Recently, optical communication has been used in various communication systems, and accordingly, an optical fiber connector for mechanically connecting a pair of optical fibers to each other has been developed. Usually, such an optical fiber connector has a pair of plugs and an adapter for connecting these plugs to each other.

FIG. 12 shows such an optical fiber connector plug, which comprises a ferrule 1, a fitting portion 3, a frame 5, a spring 7, and a fixture 9. The optical fiber 11 is inserted through the center axis of the ferrule 1, and the tip of the element wire 11 a of the optical fiber 11 is located at the tip of the ferrule 1.

In this state, the ferrule 1, the optical fiber 11, and the strand 11a are bonded and fixed. A flange-shaped fitting portion 3 is fixed to the outer periphery of the ferrule 1, and the fitting portion 3 has two recesses 3 a in the axial length direction of the ferrule 1.
Are formed. Then, as shown in FIG. 13, the ferrule 1 is inserted into the frame 5 and the recess 3a of the fitting portion 3 is formed.
Is a projection 5b formed on the inner wall of the through hole 5a of the frame 5.
Is fitted to.

A spring 7 and a fixing metal 9 are arranged in a direction opposite to the tip of the ferrule 1. And
The fixing metal 9 is inserted into the ferrule 1 together with the spring 7, and the spring 7 abuts on the flange 3 of the ferrule 1. Further, the ferrule 1 is pressed by the fixing metal 9 via the spring 7, and the claw 9 a of the fixing metal 9 is
Is engaged.

As shown in FIG. 14, the ferrule 1 is fixed to the frame 5 in a state where the ferrule 1 is pressed toward the distal end. In such an optical fiber connector plug, it is measured in advance which direction the axis of the wire 11a exposed at the tip of the ferrule 1 is eccentric with respect to the center line connecting the two concave portions 3a, and the eccentric side is measured. Fitting part 3
Is provided with an eccentric mark 3b on the outer periphery of.

[0007] The eccentric mark 3b is always in the frame 5
The eccentricity is adjusted by fitting the ferrule 1 to the frame 5 so as to be positioned on one side of the ferrule 1. FIG.
The figure shows a state in which the two optical fiber connector plugs assembled in this way are mechanically connected by the adapter 13. In this state, the eccentric marks 3b of the fitting portions 3 of the respective optical fiber connector plugs are directed to the same side, so that the connection loss of the optical fiber 11 is reduced.

[0008] Then, the respective plugs for the optical fiber connectors are inserted into the adapter 13, and the tips of the ferrules 1 are pressed together until the projection 5 d of the frame 5 is locked by the locking portion 13 a of the adapter 13. I have. On this occasion,
The ferrule 1 is pressed against each other by the action of the spring 7, and the wire 11a exposed at the tip of the ferrule 1 is connected to the PC (Ph).
ysical Contact) Connected.

[0009]

However, in such a conventional plug for an optical fiber connector, the fitting portion 3 is required.
Since only two recesses 3a are formed in the optical fiber connector, only two types of eccentricity adjustment can be performed, and it is difficult to always obtain an optimal adjustment state. In addition, there is a problem in that it is difficult to minimize the axis deviation and reduce the connection loss.

Further, since the outer diameter of the fitting portion 3 is as small as about 5 mm, it is difficult to form a large number of recesses 3a, and there is a problem that the eccentricity cannot be adjusted in multiple stages. Further, the pressing of the ferrule 1 in the distal direction is performed by the spring 7 and the fixture 9, so that the number of components constituting the plug for the optical fiber connector increases, and a large amount of work is required for assembling the plug for the optical fiber connector. There was a problem that it required man-hours.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem. An optical fiber connector capable of performing eccentricity adjustment with high accuracy and greatly reducing the number of parts compared to the conventional art. It is intended to provide a plug for use.

[0012]

According to a first aspect of the present invention, there is provided a plug for an optical fiber connector, wherein a ferrule is inserted through a through-hole having a circular cross section formed in an axial direction at the center of a frame member. In the through hole, while forming a truncated conical tapered portion having a large-diameter portion side toward the tip of the ferrule, concentrically with the through hole, and pressing the tapered portion on the outer periphery of the ferrule. abut in a state, the movement of the counter-distal direction of the ferrule
While maintaining the contact state with the small diameter portion of the tapered portion.
A rotation adjusting elastic member having a contact portion moving to the side is fixed.

According to a second aspect of the present invention, there is provided the plug for an optical fiber connector according to the first aspect, wherein an end of the ferrule is formed at an opening end of the tapered portion of the frame member on the large diameter side. An insertion hole to be inserted is formed, and a fixing member to which the flange portion of the ferrule is abutted is detachably fixed.

According to a third aspect of the present invention, in the plug for an optical fiber connector according to the second aspect, the fixing member is screwed to the frame member. The plug for an optical fiber connector according to a fourth aspect is the plug for an optical fiber connector according to any one of the first to third aspects, wherein the abutting portion of the rotation adjusting elastic member has the tapered portion. A convex portion that engages with a concave groove formed at a predetermined angle along the circumferential direction.

According to a fifth aspect of the present invention, in the optical fiber connector plug according to the fourth aspect, the rotation adjusting elastic member projects obliquely toward a tip of the ferrule, and has A plurality of elastic projections having contact portions are formed. The plug for an optical fiber connector according to claim 6 is the plug for an optical fiber connector according to claim 4 or 5,
An insertion hole through which the ferrule is inserted is formed at an opening end of the tapered portion of the frame member on the small-diameter portion side, and the engagement state of the projection with the concave groove of the tapered portion is formed at the opening end. An engagement holding member that enables the ferrule to move to a side opposite to the tip end to a position where the ferrule is not released is detachably fixed.

According to a seventh aspect of the present invention, in the optical fiber connector plug according to the sixth aspect, the engagement holding member is screwed to the frame member.

(Function) In the plug for an optical fiber connector according to the first aspect, a truncated cone-shaped tapered portion is formed in the through hole of the frame member, and the rotation adjusting elastic member is fixed to the outer periphery of the ferrule.

Further, the ferrule is inserted into the frame member, and the contact portion formed on the rotation adjusting elastic member is brought into contact with the tapered portion in a pressed state, and the ferrule is pressed toward the distal end while the frame member is pressed. Fixed to And
The eccentricity of the ferrule is adjusted by rotating the rotation adjusting elastic member inserted into the frame member. Fell
When the tool is pressed from the tip direction, the contact part is tapered.
Because it can be elastically moved to the smaller inside diameter of the part,
Without disengagement of the taper and
The ferrule is rotated while maintaining the contact state
It can be held without.

In the plug for an optical fiber connector according to the second aspect, the ferrule is inserted from the large-diameter portion side of the tapered portion of the frame member, and the fixing member is detachably attached to the opening end of the large-diameter portion of the tapered portion of the frame member. Fixed. In addition, the flange portion of the ferrule abuts on the fixing member, and the protrusion length of the ferrule in the tip direction is kept constant.

In the plug for an optical fiber connector according to the third aspect, the fixing member is easily detachably attached by being screwed to the frame member. In the plug for an optical fiber connector according to the fourth aspect, a plurality of concave grooves are formed in the tapered portion at a predetermined angle along the circumferential direction, and the concave grooves engage with the contact portions of the rotation adjusting elastic member. A projection is formed.

The engagement between the groove and the projection prevents the ferrule from rotating with respect to the frame member. Also, by rotating the rotation adjusting elastic member,
The eccentricity adjustment of the ferrule is performed at predetermined angle intervals. In the plug for an optical fiber connector according to the fifth aspect, a plurality of elastic projections projecting obliquely are formed on the rotation adjusting elastic member.

A contact portion is formed at the tip of the elastic projection, and the ferrule is fixed to the frame member. And
By moving the rotation adjusting elastic member to the side opposite to the tip of the ferrule, the contact of the elastic projection with the tapered portion is released, the rotation adjusting elastic member is rotatable, and the eccentric adjustment of the ferrule is performed. Is performed.

In the plug for an optical fiber connector according to the sixth aspect, an engagement holding member having an insertion hole formed at the opening end of the tapered portion of the frame member on the small diameter side is detachably fixed.
Then, the ferrule is elastically fixed in the axial direction by the engagement holding member fixed to the frame member, and the engagement between the concave groove of the tapered portion and the convex portion is prevented from being released.

According to the optical fiber connector plug of the present invention, the engagement holding member is screwed to the frame member,
It is easily detachable.

[0025]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment (corresponding to claims 1 to 7) of a plug for an optical fiber connector according to the present invention. It comprises a ferrule 23, a rotation adjusting elastic member 25, a fixing member 27 and an engagement holding member 29. The frame member 21 is made of a resin such as nylon 66, for example, and is formed in a cylindrical shape having a through hole 21a.

Openings 21b, 21c of frame member 21
Are formed on the inner circumference. In the vicinity of the center of the through hole 21a, the through hole 21 is formed.
A conical tapered portion 21g is formed concentrically with a, with the large diameter portion 21f facing the opening 21b. A plurality of concave grooves 21h are formed in the tapered portion 21g at a predetermined angle along the circumferential direction.

On the outer periphery of the opening 21b, a projection 21i for indicating the eccentric direction of the ferrule 23 and engaging with an adapter (not shown) is formed. Further, the ferrule 23 is made of a ceramic such as zirconia, for example, and has a flange 23a. Ferrule 2
The optical fiber 31 is inserted through the central axis of the optical fiber 3, and the tip of the element wire 31 a of the optical fiber 31 is located at the tip of the ferrule 23.

Then, in this state, the ferrule 23, the optical fiber 31, and the strand 31a are bonded and fixed.
A rotation adjusting elastic member 25 is fixed to the outer periphery of the ferrule 23 on the rear end side from the flange 23a. The rotation adjusting elastic member 25 is made of a resin such as nylon 66, for example, and has a cylindrical main body 25a.

An elastic projection 25b is formed at the end of the main body 25a in the direction of the tip of the ferrule 23 so as to project obliquely toward the tip of the ferrule 23. At the tip of the elastic projection 25b, a contact portion 25c that is in contact with the tapered portion 21g of the frame member 21 is formed, and the contact portion 25c has a projection 25d that engages with the concave groove 21h of the tapered portion 21g. are doing.

The fixing member 27 is made of a resin such as nylon 66, for example, and is formed in the shape of a flange having an insertion hole 27a at the center where the tip of the ferrule 23 is inserted. A locking hole 2 around which the tool is locked when the fixing member 27 is screwed into the frame member 21 around the insertion hole 27a.
7b are formed at two places. Further, on the outer periphery of the fixing member 27, the female screw portion 2 of the opening 21b of the frame member 21 is provided.
A male screw portion 27c screwed to 1d is formed.

Further, the engagement holding member 29 is made of a resin such as nylon 66, for example, and is formed in a flange shape having an insertion hole 29a in the center where the ferrule 23 is inserted.
A locking hole 2 around which the tool is locked when the engagement holding member 29 is screwed into the frame member 21 around the insertion hole 29a.
9b are formed at two places. Further, the engagement holding member 29
A male screw portion 29c that is screwed into the female screw portion 21e on the inner periphery of the opening 21c of the frame member 21 is formed on the outer periphery of the frame member 21.

The plug for an optical fiber connector configured as described above is assembled as described below. First, the engagement holding member 29 is screwed into the opening 21c of the frame member 21. Then, the ferrule 2 is joined together with the optical fiber 31 from the opening 21b side of the frame member 21.
3 is inserted, and the insertion hole 29 of the engagement holding member 29 is further inserted.
a.

Next, the fixing member 27 is screwed into the opening 21b of the frame member 21, and the insertion hole 27a of the fixing member 27 is inserted.
The ferrule 23 is positioned at the end. By screwing the fixing member 27, the ferrule 23 is moved in the direction opposite to the tip via the flange portion 23a of the ferrule 23, and the contact portion 25c of the rotation adjusting elastic member 25 is connected to the tapered portion 21g. It is abutted in a pressed state.

Then, the convex portion 2 formed on the contact portion 25c is formed.
5d is engaged with the concave groove 21h of the tapered portion 21g, and the ferrule 23 is fixed to the frame member 21 without being rotated. Further, the ferrule 23 is pressed toward the distal end by the elastic action of the elastic protrusion 25b, and the protrusion length of the ferrule 23 in the distal direction is kept constant through the flange 23a.

FIG. 2 shows the plug for an optical fiber connector assembled in this manner. In this state, as shown in FIG. 3, the main body 25a of the elastic projection 25b
A between the side and the end of the small diameter portion 21j of the tapered portion 21g
Is formed, and a gap B smaller than the gap A is formed between the main body 25a of the rotation adjusting elastic member 25 and the engagement holding member 29.

Then, as shown in FIG.
When 3 is pressed from the front end of the ferrule 23, the ferrule 3 is elastically moved by the gap A (not shown). At this time, since the contact portion 25c moves to the side of the inner diameter of the tapered portion 21g where the inner diameter is smaller, the elastic protrusion 25b is tilted down in the axial direction of the ferrule 23, but the elastic protrusion 25b is moved to the small diameter portion 21j of the tapered portion 21g. Never touch the edge of the

Therefore, the engagement between the not-shown convex portion 25d of the contact portion 25c and the concave groove 21h of the tapered portion 21g is not released, and the ferrule 23 is held without being rotated. On the other hand, when turning the ferrule 23 to adjust the eccentricity of the ferrule 23, the engagement holding member 29 is slightly loosened from the frame member 21, as shown in FIG.

As shown in FIG. 6, the gap B 'between the main body 25a of the rotation adjusting elastic member 25 and the engagement holding member 29 is formed between the main body 25a of the elastic projection 25b and the tapered portion. It is made larger than the gap A between the end of the small diameter portion 21j of 21g. In this state, as shown in FIG.
3 is moved in the direction opposite to the tip of the ferrule 23, so that the elastic projection 25b becomes a small diameter portion 21g of the tapered portion 21g.
abuts on the end of j.

Further, by moving the ferrule 23, the projection 25d (not shown) of the contact portion 25c and the tapered portion 2 are formed.
The engagement with the 1 g groove 21 h is released, and the ferrule 23 is released.
Is rotatable. When the ferrule 23 is released,
Due to the spring action of the elastic projection 25b, the ferrule 23 is moved in the distal direction, the projection 25d of the contact portion 25c and the concave groove 21h of the tapered portion 21g are engaged, and the original state shown in FIG. 2 is returned. .

Then, the connection loss is measured, the engagement between the projection 25d and the groove 21h is released, and the eccentric direction of the strand 31a of the optical fiber 31 is set to the side of the projection 21i of the frame member 21. By repeating the rotation of the ferrule 23 and the engagement between the convex portion 25d and the concave groove 21h, the ferrule 23 is rotated.
Eccentricity adjustment is performed. In this embodiment, the tapered portion 2
36 concave grooves 21h are formed in 1g, and the eccentricity of the ferrule 23 can be adjusted in increments of 10 degrees.

In the optical fiber connector plug configured as described above, since the ferrule 23 is rotatably fixed to the frame member 21 by using the rotation adjusting elastic member 25, the eccentricity can be adjusted with high accuracy. Can be done,
The number of parts can be greatly reduced as compared with the conventional case. Also, since the eccentricity adjustment can be performed after the optical fiber connector plug is assembled, it is not necessary to handle small components and perform the eccentricity adjustment, and the eccentricity adjustment can be easily performed.

The tapered portion 21 of the frame member 21
Since the fixing member 27 is detachably formed at the opening end 21b on the large diameter portion 21f side of g, the ferrule 23 can be easily inserted from the opening end 21b of the frame member 21.
In addition, by contacting the flange 23a of the ferrule 23 with the fixing member 27, the length of the ferrule 23 projecting in the tip direction can be kept constant.

Further, the fixing member 27 is
The fixing member 27 can be easily attached to and detached from the frame member 21 by being screwed into the fixing member 27. Since a plurality of grooves 21h are formed at a predetermined angle in the tapered portion 21g of the frame member 21, the protrusion 25d formed in the contact portion 25c of the rotation adjusting elastic member 25 and the groove 2d are formed.
By engaging with 1h, the ferrule 23 can be securely fixed to the frame member 21.

Further, the eccentricity of the ferrule 23 can be adjusted in multiple steps at predetermined angle intervals. In this embodiment, since 36 concave grooves 21h are formed in the tapered portion 21g, the eccentricity of the ferrule 23 can be adjusted in increments of 10 degrees. Further, since the eccentric direction of the strand 31a of the optical fiber 31 is aligned with the side of the projection 21i of the frame member 21, when the optical fiber connector plugs are mutually connected via the adapter, the projection 21i is on the same side. The eccentric direction can be easily adjusted by locking the eccentric direction.

Further, the eccentric direction of the wire 31a is changed to the protrusion 21i.
Therefore, the eccentricity adjustment can be performed without causing a problem such as a mistake in attaching the eccentric mark and forgetting to attach the eccentric mark, which has conventionally occurred. Since the elastic protrusion 25b is formed on the rotation adjusting elastic member 25, a spring and a fixing member for pressing the spring are not required, and a plug for an optical fiber connector that can be connected to a PC with a simple structure can be configured.

That is, the number of components constituting the optical fiber connector plug can be reduced, and the number of assembly steps for the optical fiber connector plug can be greatly reduced. Then, by moving the rotation adjusting elastic member 25 to the side opposite to the tip of the ferrule 23, the contact of the elastic protrusion 25b with the tapered portion 21g is released, so that the ferrule 2 can be easily formed.
3 can be made rotatable.

The tapered portion 21g of the frame member 21
Since the engagement holding member 29 is detachably fixed to the opening end 21c of the small diameter portion 21j side, the ferrule 23 can be elastically fixed in the axial direction and the concave groove 21 of the tapered portion 21g.
Since the engagement state between h and the projection 25d of the contact portion 25c can be maintained, the rotation of the ferrule 23 can be prevented.

Further, since the engagement holding member 29 can be fixed by being screwed to the frame member 21, the engagement holding member 2 can be fixed.
9 can be easily attached to and detached from the frame member 21. FIG. 8 shows a second embodiment (corresponding to claims 1, 4 and 5) of an optical fiber connector plug according to the present invention. , Ferrule 23 and elastic member 43 for rotation adjustment.

The frame member 41 is made of, for example, nylon 66
And is formed in a cylindrical shape having an insertion hole 41a at one end into which the tip of the ferrule 23 is inserted.
A frustoconical tapered portion 41c is formed near the center of the frame member 41 in the axial direction with the large-diameter portion 41b facing the insertion hole 41a. Further, a frusto-conical taper introduction part 41f in which the large diameter part 41d is arranged in the opening part 41e of the frame member 41 is formed concentrically with the taper part 41c, and a surface where the taper part 41c and the taper introduction part 41f are in contact. Is formed with a constricted portion 41g.

The tapered portion 41c is formed with a plurality of grooves 41h at a predetermined angle along the circumferential direction. A projection 41i is formed on the outer periphery of the frame member 41 on the side where the insertion hole 41a is formed. The ferrule 23 is the same as the ferrule 23 of the first embodiment. The optical fiber 11 is inserted through the central axis, and the tip of the element wire 11a is located at the tip.

Further, a rotation adjusting elastic member 43 is fixed to the outer periphery of the ferrule 23 on the rear end side from the flange 23a. The rotation adjusting elastic member 43 is made of a resin such as nylon 66, for example, and has a cylindrical main body 43a. At the end of the main body 43a in the direction of the tip of the ferrule 23, an elastic projection 43b that projects obliquely toward the tip of the ferrule 23 is formed.

A contact portion 43c is formed in the distal end direction of the elastic projection 43b so as to contact the tapered portion 41c of the frame member 41. The contact portion 43c is formed by a concave groove 41h of the tapered portion 41c.
And has a not-shown convex portion that engages with. Further, a flange-shaped holding portion 43d is formed at the end of the main body 43a opposite to the tip of the ferrule 23.

In the optical fiber connector plug configured as described above, first, the opening 41 of the frame member 41 is used.
The ferrule 23 is inserted from the e side. Next, the tip of the elastic projection 43b is brought into contact with the tapered introduction portion 41f, and the elastic projection 43b is tilted in the axial direction of the ferrule 23 along the slope of the tapered introduction portion 41f.

Then, as shown in FIG.
The tip of b is tilted down until it comes into contact with the constricted portion 41g of the frame member 41, and the elastic protrusion 43b is moved to the tapered portion 41c. Further, as shown in FIG.
Along c, the elastic projection 43b is raised by the elastic force,
The contact portion 43c contacts the tapered portion 41c, and the tapered portion 4
The notch 41h of the contact part 43c is engaged with the concave groove 41h of 1c.

Further, the elastic force of the elastic projection 43b causes the flange 23a of the ferrule 23 and the rotation adjusting elastic member 4 to rotate.
The three holding portions 43d are pressed around the insertion hole 41a of the frame member 41 and the opening 41e, respectively, to form an optical fiber connector plug. On the other hand, when the ferrule 23 is rotated to adjust the eccentricity of the ferrule 23, the convex portion (not shown) of the contact portion 43c and the tapered portion 41
The ferrule 23 may be moved in the direction opposite to the tip until the engagement of the c with the concave groove 41h is released.

In the plug for an optical fiber connector according to this embodiment, substantially the same effects as those of the first embodiment can be obtained. However, in this embodiment, the frame member 41 serves as both the fixing member and the engagement holding member. Therefore, a plug for an optical fiber connector having a smaller number of components can be formed, and the number of steps required for assembling the plug for an optical fiber connector can be greatly reduced.

Further, since the ferrule 23 can be rotated only by moving the ferrule 23 to the side opposite to the distal end, the eccentricity can be easily adjusted. In the above-described embodiment, an example has been described in which the frame members 21 and 41 are formed of nylon 66. However, the frame members 21 and 41 may be formed of a metal such as stainless steel. Also, the frame member 2
Although an example has been described in which the cylindrical members 1 and 41 are formed in a cylindrical shape, for example, the outer periphery of the frame members 21 and 41 may be formed in a square shape.

The example in which the rotation adjusting elastic members 25 and 43 are formed of nylon 66 has been described.
It may be formed of a metal such as stainless steel or a shape memory alloy. Furthermore, the example in which the number of the elastic protrusions 25b and 43b of the rotation adjusting elastic members 25 and 43 is four has been described, but the number of the elastic protrusions 25b and 43b may be two or more. Also,
The number of the concave grooves 21h and 41h of the tapered portions 21g and 41c is 3
The example in which the number is six is described.
The number of 1h may be 72 and the ferrule 23 may be rotatable in increments of 5 degrees, or the number of the concave grooves 21h and 41h may be 18 and the ferrule 23 may be rotatable in increments of 20 degrees.

In the above-described embodiment, the example in which the flange 23a is formed on the ferrule 23 has been described. For example, as shown in FIG. 11, the flange 25e is formed on the rotation adjusting elastic member 25. Is also good.

[0061]

As described above, in the plug for an optical fiber connector according to the first aspect, the ferrule is rotatably fixed to the frame member using the rotation adjusting elastic member.
The eccentricity adjustment can be performed with high accuracy, and the number of parts can be significantly reduced as compared with the related art. Fell
When the tool is pressed from the tip direction, the contact part is tapered.
Because it can be elastically moved to the smaller inside diameter of the part,
Without disengagement of the taper and
The ferrule is rotated while maintaining the contact state
It can be held without.

In the plug for an optical fiber connector according to the second aspect, since the fixing member is detachably formed at the opening end on the large diameter side of the tapered portion of the frame member, the ferrule is easily inserted from the opening end of the frame member. be able to. In the optical fiber connector plug according to the third aspect, since the fixing member can be fixed by screwing the fixing member to the frame member, the fixing member can be easily attached to and detached from the frame member.

In the plug for an optical fiber connector according to the fourth aspect, the plurality of concave grooves are formed at a predetermined angle in the tapered portion of the frame member. The ferrule can be reliably fixed to the frame member by engaging with the concave groove. Further, the eccentricity adjustment of the ferrule can be performed in multiple stages at predetermined angle intervals.

In the optical fiber connector plug according to the fifth aspect, since the elastic projection for the rotation adjusting elastic member is formed, there is no need for a spring and a fixing member for holding the spring. A connector plug can be configured. That is, the number of components constituting the optical fiber connector plug can be reduced, and the man-hour for assembling the optical fiber connector plug can be reduced.

According to the optical fiber connector plug of the present invention, since the engagement holding member is detachably fixed to the opening end of the tapered portion of the frame member on the small diameter side, the ferrule can be elastically fixed in the axial direction. In both cases, the engagement between the concave groove of the tapered portion and the convex portion of the contact portion can be maintained, so that the rotation of the ferrule can be prevented. In the optical fiber connector plug according to the seventh aspect, since the engagement holding member can be fixed by screwing the engagement holding member to the frame member, the engagement holding member can be easily attached to and detached from the frame member.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of an optical fiber connector plug of the present invention.

FIG. 2 is a cross-sectional view showing a first embodiment of the optical fiber connector plug of the present invention.

FIG. 3 is a sectional view showing details of the optical fiber connector plug of FIG. 2;

FIG. 4 is a cross-sectional view showing a state in which the ferrule of the optical fiber connector plug of FIG. 2 is pressed from the front end direction.

FIG. 5 is a cross-sectional view showing a state where an engagement holding member of the optical fiber connector plug of FIG. 2 is loosened.

FIG. 6 is a sectional view showing details of FIG. 5;

FIG. 7 is a cross-sectional view showing a state where a ferrule of the optical fiber connector plug of FIG. 2 is rotated.

FIG. 8 is a sectional view showing a second embodiment of the optical fiber connector plug of the present invention.

9 is a cross-sectional view showing a state in which the ferrule of the optical fiber connector plug of FIG. 8 is inserted into a frame member.

FIG. 10 is a cross-sectional view showing a state where the optical fiber connector plug of FIG. 8 is assembled.

FIG. 11 is a cross-sectional view showing a state in which a collar portion is formed on the rotation adjusting elastic member.

FIG. 12 is a sectional view showing a conventional optical fiber connector plug.

FIG. 13 is an explanatory diagram showing details of a fitting state between the fitting portion and the frame in FIG. 12;

FIG. 14 is a cross-sectional view showing a state where the optical fiber connector plug of FIG. 12 is assembled.

FIG. 15 is a cross-sectional view showing a state where a conventional optical fiber connector plug is connected via an adapter.

[Explanation of symbols]

 21 frame member 21a through hole 21f large diameter portion 21g taper portion 21h concave groove 21j small diameter portion 23 ferrule 23a flange 25 rotation adjusting elastic member 25b elastic protrusion 25c contact portion 25d convex portion 27 fixing member 27a insertion hole 29 Joint holding member

Claims (7)

(57) [Claims] 1. A plug for an optical fiber connector, wherein a ferrule is inserted through a through hole having a circular cross section formed in the axial direction at the center of a frame member, wherein the through hole is concentric with the through hole. with the large diameter portion to form a frustoconical tapered portion positioned toward the distal end of the ferrule, the outer circumference of the ferrule, and contact with the pressing state to the tapered portion, the anti-tip side of the ferrule
While maintaining the contact state with the movement in the
A plug for an optical fiber connector, wherein a rotation adjusting elastic member having a contact portion moving toward the small diameter portion side of the portion is fixed. 2. The plug for an optical fiber connector according to claim 1, wherein an insertion hole through which a tip of the ferrule is inserted is formed at an opening end of the tapered portion of the frame member on the large diameter portion side. A plug for an optical fiber connector, wherein a fixing member to which the flange portion of the ferrule abuts is fixed detachably. 3. The plug for an optical fiber connector according to claim 2, wherein said fixing member is screwed to said frame member. 4. The optical fiber connector plug according to claim 1, wherein the abutting portion of the rotation adjusting elastic member is formed along the circumferential direction of the tapered portion. A plug for an optical fiber connector, wherein a projection is formed to engage with a concave groove formed at a predetermined angle. 5. The plug for an optical fiber connector according to claim 4, wherein the rotation adjusting elastic member projects obliquely toward a tip of the ferrule and has a plurality of elastic projections having the contact portion at the tip. A plug for an optical fiber connector, wherein a plug is formed. 6. The plug for an optical fiber connector according to claim 4, wherein an insertion hole through which the ferrule is inserted is formed at an opening end of the tapered portion of the frame member on the small diameter side. At this open end, an engagement holding member that enables movement of the ferrule to the side opposite to the tip end to a position where the engagement of the convex portion with the concave groove of the tapered portion is not released is detachably fixed. A plug for an optical fiber connector. 7. The plug for an optical fiber connector according to claim 6, wherein said engagement holding member is screwed to said frame member.