JP2002036303A - Injection molding die for optical connector ferrule - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide such an injection molding die for an optical connector ferrule that the same is constituted so as to regulate the position of a core holding a core pin. SOLUTION: The injection molding die for the optical connector ferrule is equipped with the first die parts 5 constituting the outside diameter of the insertion part 22 of the optical connector ferrule 2, the second die parts 6 constituting both the outside diameter of the base part 20 of the optical connector ferrule 2 and the outside diameter of a flange part 21, a core pin 7 constituting both the inside diameter of an optical fiber-inserting hole 24 of the optical connector ferrule 2 and the inside diameter of a bare optical fiber-inserting fiber 223 together with the first die parts 5 and the second die part 6 and a core pin aligning device driving a core 4 into which the tip of the core pin 7 is inserted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection mold for an optical connector ferrule, and more particularly to an injection mold for an optical connector ferrule having a structure for adjusting a position of a core holding a core pin.

[0002]

2. Description of the Related Art A conventional example will be described with reference to FIGS. FIG. 4 shows the optical connector ferrule holding the optical fiber, and FIG. 5 shows the optical connector ferrule injection mold. In order to optically interconnect one optical fiber 1 and the other optical fiber 1 ′, the coatings at the tips of both optical fibers are stripped off, and the bare optical fiber 11 is exposed. One end of the optical fiber 1 is inserted into the optical fiber insertion hole 24 of the one optical connector ferrule 2 from the side of the bare optical fiber 11, and the leading end of the bare optical fiber 11 is formed on the leading end surface of the insertion portion 22. Fiber insertion hole 223
And one of the optical connector ferrules 2
To join. Similarly, the other optical fiber 1 ′ is connected from the bare optical fiber 11 side to the other optical connector ferrule 2 ′.
Is inserted into the optical fiber insertion hole 24, and the distal end of the bare optical fiber 11 is fitted into the bare optical fiber insertion hole 223 formed on the distal end surface of the insertion portion 22, and is connected to the other optical connector ferrule 2 '. I do. Here, the distal ends of the insertion sections 22 of the two optical connector ferrules are fitted and opposed to the alignment sleeve 23, thereby aligning the optical fibers with high accuracy. That is, the bare optical fiber 1 fitted into the bare optical fiber fitting hole 223 formed on the distal end surface of the insertion portion 22 of the one optical connector ferrule 2.
1 and a bare optical fiber insertion hole 223 formed on the distal end surface of the insertion portion 22 of the other optical connector ferrule 2 '.
The leading end surfaces of the bare optical fibers 11 fitted in are aligned on a straight line. Reference numeral 20 denotes a base of the optical connector ferrule, and reference numeral 21 denotes a flange.

In the optical connector ferrules 2 and 2 ', the concentricity between the outer diameter of the insertion portion 22 and the bare optical fiber insertion hole 223 formed on the distal end surface greatly affects the performance of optical coupling. Therefore, it is necessary to prepare an optical connector ferrule injection molding die which is manufactured with high accuracy to secure this concentricity. A conventional example of an optical connector ferrule injection mold will be described with reference to FIG. FIG. 4 is an exploded perspective view of a conventional example.

In FIG. 5, reference numeral 3 denotes a first base, 4 denotes a core, 5 denotes a first mold part, 6 denotes a second mold part, 7 denotes a core pin, and 8 denotes a second base. When the first mold part 5 is engaged with the second mold part 6, an outer mold corresponding to the outer shape of the optical connector ferrule 2 is formed in the second mold part 6. The core pin 7 includes an insertion hole corresponding pin 71 corresponding to the bare optical fiber insertion hole 223 during injection molding, an insertion hole corresponding pin 72 corresponding to the optical fiber insertion hole 24 for holding the insertion hole corresponding pin 71 and performing injection molding. A pin supporting portion 73 for holding the pin 72 corresponding to the insertion hole.
The core pin 7 is connected to the second base 8 via the pin support 73.
Attached to.

[0005] The core 4 has a pin 7 corresponding to the insertion hole of the core pin 7.
It has a core pin holding cylinder 41 in which an insertion hole 411 into which the first pin 1 is inserted is formed. The core 4 is attached to the first mold part 5 with the core pin holding cylinder 41 facing the center hole 51. Here, in order to conceptually explain the molding of the optical connector ferrule 2, the first base 3, the first mold part 5, the second mold part 6, and the second base 8 are driven to interact with each other. Then, the core pin 7 is inserted into the center hole 6 in the second mold part 6.
1, and a part of the insertion hole corresponding pin 71 of the core pin 7 and a part of the insertion hole corresponding pin 72 are inserted through the center hole 51 of the first mold part 5, and the insertion hole corresponding pin 71 is inserted.
Into the insertion hole 411 of the core 4. In this state, the first
The core pin 7 corresponding to the bare optical fiber insertion hole 223 and the optical fiber insertion hole 24 penetrates through the outer mold formed by the mold part 5 and the second mold part 6. A mold corresponding to the optical connector ferrule 2 is formed therebetween. Next, from the second base 8 to the second mold part 6
The optical connector ferrule 2 can be formed by supplying a synthetic resin to the previous mold through the injection hole 62 of the first mold part 5 and the injection hole 52 of the first mold part 5.

[0006]

In the above conventional example, the concentricity between the center line of the bare optical fiber insertion hole 223 formed on the distal end surface of the insertion portion 22 and the surface of the insertion portion 22 is precisely secured. It is important to be done. If this concentricity is not guaranteed, the insertion portion 22 of the optical fiber 1, 1 '
Even if the two members are fitted and opposed to the alignment sleeve 23, the two bare optical fiber insertion holes 223 are not completely aligned, and sufficient optical transmission is not performed between the bare optical fibers 11 inserted therein.

The above-described conventional example of the optical connector ferrule injection molding die includes an inner diameter of the center hole 51 of the first die part 5 corresponding to an outer diameter of the insertion portion 22 of the optical connector ferrule 2, and a bare optical fiber insertion hole 223. The outer diameter of the insertion hole corresponding pin 71 of the core pin 7 corresponding to the
The insertion hole 411 of the core pin holding cylinder 41 for holding the
Clearance between the inner diameter of the center hole 51 of the first mold part 5, the outer diameter of the pin 72 corresponding to the optical fiber insertion hole, and the inner diameter of the center hole 51 of the first mold part 5 The concentricity of the mold part 6 itself affects the accuracy of the optical connector ferrule to be molded.

In order to manufacture a mold for injection molding of an optical connector ferrule that eliminates the above factors affecting accuracy, first, ultra-high-precision processing technology is required to manufacture a mold part. It is necessary to evaluate whether or not the obtained mold parts are satisfactory with a super-high-precision measuring instrument.
The present invention has a configuration for adjusting the position of the core that holds the core pin, and easily sets the pin corresponding to the insertion hole of the core pin at the center of the inner diameter of the mold corresponding to the insertion portion without disassembling the mold. An object of the present invention is to provide an optical connector ferrule injection molding die which can solve the above-mentioned problems.

[0009]

According to the present invention, there is provided an injection molding die for an optical connector ferrule, wherein the molding die comprises a first die part (5) constituting an outer diameter of an insertion portion (22) of the optical connector ferrule (2). The light of the optical connector ferrule 2 together with the second mold part 6, the first mold part 5, and the second mold part 6 constituting the outer diameter of the base part 20 and the outer diameter of the flange part 21 of the optical connector ferrule 2 are shown. Optical connector ferrule injection molding metal having a core pin 7 constituting the inner diameter of the fiber insertion hole 24 and the inner diameter of the bare optical fiber insertion hole 223, and including a core pin alignment device for driving the core 4 into which the tip of the core pin 7 is inserted. Configured mold.

[0010] Claim 2: In the optical connector ferrule injection mold according to claim 1, the core pin centering device comprises laminated piezoelectric element rods 42, 43 for driving the core 4.
An optical connector ferrule injection molding die having the following configuration was constructed. Claim 3: In the optical connector ferrule injection mold according to claim 2, the laminated piezoelectric element rods 42 and 43 are formed in horizontal and vertical biaxial directions, respectively. Was configured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is an exploded perspective view of an embodiment of an injection mold for an optical connector ferrule. FIG. 2 is a diagram illustrating a mold. In the embodiments, members common to the conventional example are assigned the same reference numerals. When the first mold part 5 is engaged with the second mold part 6, an outer mold corresponding to the outer shape of the optical connector ferrule 2 is formed in the second mold part 6, as in the conventional example. You.

The core pin 7 includes an insertion hole corresponding pin 71 corresponding to the bare optical fiber insertion hole 223 during injection molding, and an insertion hole corresponding pin corresponding to the optical fiber insertion hole 24 during injection molding. 72,
A pin supporting portion 73 for holding the pin 72 corresponding to the insertion hole. The core pin 7 is attached to the second base 8 via a pin support 73. The core 4 has an insertion hole 411 into which the pin 71 corresponding to the insertion hole of the core pin 7 is inserted. The inner diameter of the insertion hole 411 is formed slightly larger than the outer diameter of the insertion hole corresponding pin 71 having an outer diameter slightly larger than the outer diameter of the bare optical fiber. This core 4 is a core holding member 4
It is assembled into the first mold part 5 while being held at zero. At the center of the upper part of the core holding member 40, the core loose fitting concave portion 40 is provided.
1 is formed. Reference numeral 42 denotes a laminated piezoelectric element rod in the horizontal axis direction, and reference numeral 43 denotes a laminated piezoelectric element rod in the vertical axis direction. 44 is a horizontal plunger. 402 is a horizontal through hole, 4
03 denotes a vertical through hole, and 404 denotes a horizontal screw hole. The horizontal through hole 402, the vertical through hole 403, and the plunger hole 404 all communicate with the core loose fitting recess 401.

The first mold part 5 has a notch 53 in which the core holding member 40 in a state where the core 4 is held by the core holding member 40 is notched downward. A central hole 51 having an inner diameter corresponding to the outer diameter of the insertion portion 22 of the optical connector ferrule 2 is formed in the center of the first mold part 5 on the side of the second mold part 6. The core 4, the core holding member 40, the horizontal axis direction laminated piezoelectric element rod 42, the vertical axis direction laminated piezoelectric element rod 43, the horizontal plunger 44, and the vertical direction plunger 55 constitute a core pin centering device.

Here, the order of molding the optical connector ferrule 2 will be described. The core holding member 40 holding the core 4 in the core loose fitting concave portion 401 is prepared. The core 4 has a horizontal screw hole 40 in the core loose fitting recess 401 of the core holding member 40.
4 is resiliently biased from one direction by a horizontal plunger 44 screwed into the horizontal screw hole 404.
The horizontal axially laminated piezoelectric element rod 42 inserted into the horizontal through hole 402 formed opposite to the front side abuts from the other direction. The core 4 has a first mold part 5 in the vertical direction.
The vertical plunger 55 screwed into the vertical screw hole 54 is elastically biased from above, and the vertical through hole 4 formed opposite the vertical screw hole 54.
The vertical axially laminated piezoelectric element rod 43 inserted into the element 03 is abutted from below. The core holding member 40 is positioned and fixed in a notch 53 formed below the first mold part 5, and the first base 3, the first mold part 5, the second mold part 6, and the second The base pins 8 are driven and engaged with each other, and the core pin 7 is inserted into the second mold part 6 through the center hole 61,
Then, a part of the insertion hole corresponding pin 71 of the core pin 7 and a part of the insertion hole corresponding pin 72 are inserted through the center hole 51 of the first mold component 5, and the insertion hole corresponding pin 71 is inserted into the insertion hole 41 of the core 4.
Insert into 1. Here, the core pin 7 corresponding to the bare optical fiber insertion hole 223 and the optical fiber insertion hole 24 penetrates through the outer die constituted by the first die part 5 and the second die part 6, and A mold corresponding to the optical connector ferrule 2 is formed between the mold and the core pin 7.

When the optical connector ferrule injection molding die is assembled as described above, first, the injection hole 62 of the second die part 6 and the injection hole of the first die part 5 from the second base 8. The optical connector ferrule 2 is prototyped by supplying a synthetic resin through 52. FIG. 4 (b),
Referring to FIG. 4 (c), the molded product of the optical connector ferrule 2 manufactured as a trial is less likely to be molded to satisfy the concentricity as shown in FIG. It is expected to be.

Therefore, the concentricity of the molded optical connector ferrule is measured. That is, the amount of deviation of the center of the bare optical fiber insertion hole 223 from the center of the outer diameter of the insertion portion 22 of the optical connector ferrule 2 is separately measured by a measuring device (not shown). Here, the pin 71 corresponding to the insertion hole of the core pin 7 is used.
Is driven to drive the core 4 of the core pin centering device so that the insertion hole corresponding pin 71 coincides with the center of the outer diameter of the insertion portion 22. In this drive, a voltage is applied to the horizontal-axis laminated piezoelectric element rod 42 and the vertical-axis laminated piezoelectric element rod 43, and these are electrostricted and displaced against the bias of the horizontal plunger 44 and the vertical plunger 55. It is implemented by doing. The pin 71 corresponding to the insertion hole of the core pin 7 is
By displacing the core 4 inserted in 1 as described above, the insertion hole corresponding pin 71 can be aligned with high accuracy. An example of the relationship between the applied voltage and the displacement is shown in FIG.

By arranging the laminated piezoelectric element rods in two horizontal and vertical directions with respect to the core 4 holding the core pin 7, the core 4 holding the core pin 7 is adjusted two-dimensionally.
The pin 71 corresponding to the insertion hole of the core pin 7 can be easily and accurately centered on the center of the inner diameter of the mold corresponding to the insertion portion 22 without disassembling the mold.

[0018]

As described above, according to the present invention, the parts of the injection mold for the optical connector ferrule can be manufactured with the conventional accuracy, and the optical connector can be manufactured without being evaluated by an ultra-high precision measuring instrument. The concentricity, which is an important dimension as a ferrule, can be obtained with high accuracy.

[Brief description of the drawings]

FIG. 1 illustrates an embodiment.

FIG. 2 is a diagram showing a partial cross section of the embodiment.

FIG. 3 is a view showing displacement characteristics of a laminated piezoelectric element rod.

FIG. 4 is a diagram illustrating a connection state of an optical fiber.

FIG. 5 is a diagram illustrating a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 One optical fiber 1 'The other optical fiber 11 Bare optical fiber 22 Insertion part 223 Bare optical fiber insertion hole 2 One optical connector ferrule 2' The other optical connector ferrule 23 Alignment sleeve 24 Optical fiber insertion hole 3 First base 4 core 40 core holding member 401 core fitting concave portion 402 horizontal through hole 403 vertical through hole 404 horizontal screw hole 41 core pin holding tube 411 insertion hole 42 horizontal axis laminated piezoelectric element rod 43 vertical axis laminated piezoelectric element rod 44 horizontal Directional plunger 5 First mold part 51 Center hole 52 Injection hole 53 Notch 55 Vertical plunger 6 Second mold part 62 Injection hole 7 Core pin 71 Insertion hole corresponding pin 72 Insertion hole corresponding pin 73 Pin support 8 2 base

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shigehiro Nagaya 1-21-2 Dogenzaka, Shibuya-ku, Tokyo Japan Aviation Electronics Industry Co., Ltd. F-term (reference) 2H036 MA05 QA18 QA20 4F202 AH34 CA11 CB01 CK11 CK25 CK42 CM03 CM17

Claims (3)

[Claims] 1. An injection molding die for an optical connector ferrule, wherein the molding die is a first die part constituting an outer diameter of an insertion portion of the optical connector ferrule, an outer diameter of a base of the optical connector ferrule and a flange portion. The second mold part constituting the outer diameter, the first mold part
A core pin that defines the inner diameter of the optical fiber insertion hole and the inner diameter of the bare optical fiber insertion hole of the optical connector ferrule together with the mold part and the second mold part, and drives the core into which the tip of the core pin is inserted. An optical connector ferrule injection molding die comprising a centering device. 2. The optical connector ferrule injection molding die according to claim 1, wherein the core pin alignment device has a laminated piezoelectric element rod for driving the core. Type. 3. The optical connector ferrule injection molding die according to claim 2, wherein the laminated piezoelectric element rod is formed in each of two horizontal and vertical axial directions. Type.