JPH1177741A - Mold for optical connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the irregularity of the positions of the fiber holes of a molded product by notching a part of a piece so that the upper end parts of small round holes are notched and protruding the core pins partially inserted into the small round holes above the piece and pressing the protruded parts by a press material. SOLUTION: The piece 16 of a lower mold 12 is constituted of a main body 160 and a press material 164. The main body 160 has such a shape that the upper part of the piece 16 is cut off by an imaginary xz surface notching the upper ends of small and large round holes 18, 20. The press material 164 is the square bar shape superposed on the main body 160 and has the projected part 166 corresponding to a recessed part 162. Core pins 26 are inserted in the small round holes 18 and guide hole molding pins 28 are inserted in the large round holes 20 and a core 22 is superposed on the lower mold 12. The upper end bow-shaped cross-sectional parts of the core pins 26 and the guide hole molding pins 28 protrude to the surface of the main body 160 and the protruded parts of them are pressed from above by the press material 164.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for manufacturing a ferrule of an MT type optical connector (F12 type multi-core optical fiber connector specified in JIS C5981). (To be described).

[0002]

2. Description of the Related Art FIG. 3 shows a ferrule 10 of an MT type multi-core optical connector. 11 is a fiber hole and 13 is a guide pin hole.

FIG. 4 schematically shows a mold for manufacturing the ferrule 10. 12 is the entire lower die, 14 is its main body, 16 is a round hole type piece, and it has a small round hole 18 and a large round hole 2.
Has zero.

[0004] 22 is the whole core, 24 is its body, 26
Is a core pin (for molding the fiber hole 11), and 28 is a molding pin for a guide hole. Reference numeral 30 denotes an entire upper mold having a resin inlet 32.

[Mold assembly] The core pin 26 is inserted into the small round hole 18.
The guide hole forming pin 28 is inserted into the large round hole 20, and the core 22 is stacked on the lower mold 12, and the upper mold 30 is stacked thereon.

Then, a ferrule 10 is obtained by resin molding.

[Advantage of Round Hole Type Piece 16] In a normal ferrule molding die, a small round hole 18 and a large round hole 20 are V-grooves. However, if this V-groove type piece is used, the resin protrudes into the V-groove at the time of molding, and the V-groove must be cleaned each time molding is performed. On the other hand, when the round hole type is used, there is an advantage that the resin does not protrude at the time of molding, and the labor for cleaning can be greatly reduced.

[0008]

As shown exaggeratedly in FIG. 5, a clearance 34 occurs between the small round hole 18 and the core pin 26. Further, the position where the clearance 34 occurs is not fixed. For this reason, even if the precision of the position of the small round hole 18 is high, the position of the fiber hole 11 of the molded product varies due to the clearance 34.

[0009]

The present invention (see FIG. 1) comprises:
At least the top of the small round hole 18 is chipped,
Is cut out, a part of the core pin 26 inserted into the small round hole 18 protrudes above the piece 16, and the protruding part is pressed by the pressing member 164. I do.

[0010] The phrase "a part of the piece 16 is cut off so that at least the upper end of the small round hole 18 is chipped" means that not only the small round hole 18 but also the large round hole 20 may be included. That is.

The "part of the piece 16 is notched" means that the entire upper end of the piece 16 is removed as shown in FIG. 1 or as shown in FIG. The piece 16 may be cut out like a slit.

[Operation] As shown in FIG.
The core pin 26 is pressed against the bottom of the small round hole 18 by the pressing member 164. In all the small round holes 18, the center of the small round hole 18 and the center of the core pin 26 are on the same y-axis. Therefore, the accuracy of the position of the small round hole 18 becomes the accuracy of the position of the fiber hole 11 of the molded product as it is (accuracy similar to that of the conventional V-groove type piece is obtained).

[0013]

First Embodiment FIG. 1 shows the case of FIG. [Structure of Piece 16] The piece 16 of the lower die 12 is composed of a main body 160 and a pressing member 164. The main body 160 has a small round hole 18.
And the virtual xz plane in which the upper end of the large round hole 20 is cut out,
6 is a cutaway top view. However, since the large round hole 20 and the small round hole 18 have different sizes (diameters), the main body 1
On the upper surface of 60, a shallow concave portion 162 based on the step is formed. The holding member 164 is a square member that is superimposed on the main body 160 and has a convex portion 166 corresponding to the concave portion 162. Portions other than the piece 16 are the same as the conventional mold.

[Mold Assembly] As in the conventional case, the core pin 26 is inserted into the small round hole 18, the guide hole forming pin 28 is inserted into the large round hole 20,
Each is inserted, and the core 22 is placed on the lower mold 12.
A part of the core pin 26 and the guide hole forming pin 28 (the upper end arc-shaped cross section) protrudes onto the main body 160 (FIG. 1).
(B)). The protruding portion is pressed down from above by a pressing member 164.

The parts other than the piece 16 are assembled in the same manner as in the prior art.

[Molding] A resin is press-fitted into the metal mold assembled as described above to form a ferrule 10.

[0017]

[Embodiment 2] This is the case of FIG. A groove 168 is provided in the piece 16, and the bottom surface (FIG.
Like the upper surface of the piece 16, the upper ends of the small round hole 18 and the large round hole 20 are cut out. In this case, the holding material 1
64 has a thin plate shape.

In this case, assembling and forming of the mold are performed in accordance with the case of FIG.

[0019]

According to the present invention, the variation in the position of the fiber hole 11 of the molded product due to the gap between the core pin 26 and the small round hole 18 can be reduced.

[Brief description of the drawings]

FIG. 1A is an explanatory view of a mold according to an embodiment of the present invention, and FIG. 1B is an explanatory view of a state in which a pressing member 164 is overlaid on a main body 160 of a bridge.

FIGS. 2A and 2B are explanatory views of a lower mold, and FIG. 2B is a cross-sectional view taken along line BB of FIG. 2A according to another embodiment of the present invention.

FIG. 3 is an explanatory view of a ferrule to be manufactured.

FIG. 4 is an explanatory view of a conventional mold.

FIG. 5 is an explanatory view of a problem of a conventional mold.

DESCRIPTION OF SYMBOLS 10 Ferrule 11 Fiber hole 12 Lower mold 13 Guide pin hole 14 Lower mold main body 16 pieces 160 pieces Main body 162 Concave part 164 Pressing material 166 Convex part 168 Groove 18 Small round hole 20 Large round hole 22 Core 24 Core body 26 Core pin 28 Guide hole forming pin 30 Upper die 32 Resin entrance 34 Clearance

Claims (1)

[Claims] 1. A round hole type piece 16 having a small round hole 18 and a large round hole 20. A core pin 26 is inserted into the small round hole 18, and a guide hole forming pin 28 is inserted into the large round hole 20. In the optical connector mold, the fiber hole 11 of the ferrule is formed by the core pin 26 and the guide pin hole 13 is formed by the guide hole forming pin 28 by resin molding.
A part of the piece 16 is cut out so that at least the upper end of the small round hole 18 is chipped, and a part of the core pin 26 inserted into the small round hole 18 protrudes above the piece 16. A mold for an optical connector, wherein a protruding portion is pressed by a pressing member 164.