JP2003103570A - Mold equipment for injection molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a closing movement smooth in mold equipment conducting multy-cavity molding of molded articles. SOLUTION: The mold equipment 100 is composed of a fixed mold 110 and a movable mold 120 which have a plurality of sets of fixed-side insert dies A supplying a molding material and movable-side insert dies B supplied with the material. First, the fixed mold 110 and the movable mold 120 are aligned in position with each other by a first positioning means composed of a pin 48 of the fixed mold 110 and an insertion hole of the movable mold 120, and then the fixed-side insert die A and the movable-side insert die B are aligned in position with each other by second positioning means composed of pins 38 of the fixed-side insert dies A and insert holes of the movable-side insert dies B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding die device, and particularly preferably, it can be used for injection molding to obtain a highly accurate molded product such as a ceramic ferrule used for a connector for connecting an optical fiber. Regarding mold equipment.

[0002]

2. Description of the Related Art With the development of optical communication networks, optical fiber cables have been laid and the opportunities for using optical fiber cords have increased, and along with this, optical connectors used for connecting optical fiber cords have been developed. Although there are various types of optical connectors, in FC type connectors, an optical fiber of an optical fiber cord is inserted into a center through hole of a ferrule used as a plug of the optical connector. This ferrule is produced by injection molding a mixture of zirconia powder and an organic binder using a mold device.

The applicant of the present invention has filed an invention relating to a method and apparatus for manufacturing a ferrule in Japanese Patent Application No. 2000-28809.
Filed as No. 1 (application date: September 22, 2000). The mold apparatus according to this application is roughly as follows. FIG. 5 is a sectional view of a main part of a mold device for injection molding a ferrule. In the mold device 100, the right half 110 is a fixed mold and the left half 120 is a movable mold.

In the fixed die 110, the core pin 9
The fixed-side insert 7 fixed to the fixed-side insert 7, the fixed-side mold plate 5 to which the fixed-side insert 7 is fixed, and the fixed-side attachment plate 1 to which the fixed-side mold plate 5 is fixed via the manifold spacer 3. A guide pin 18 that guides the reciprocating movement of the movable mold plate 17 is fixed to the fixed mold plate 5. Further, the manifold spacer 3 is connected to a member forming a material supply path, that is, a sprue 2 for introducing and flowing a molten molding material melted by a heating cylinder (not shown), and a downstream side of the sprue 2, A manifold 4 for flowing the molten molding material introduced from the sprue 2,
A hot runner nozzle 6 that is connected to the downstream side of the manifold 4 and that causes the molten molding material introduced from the manifold 4 to flow is fixed. The nozzle 6 penetrates through the fixed-side mold plate 5, and its tip portion communicates with the starting end of a runner that communicates with the cavity 30 provided in the movable-side insert 10 in the mold closed state, and causes the molten molding material to flow into the runner. .

A coil heater 40 as heating means is provided around each of the sprue 2, the manifold 4 and the nozzle 6.
Are arranged in a spiral.

The core pin 9 is a member for forming an inner peripheral surface of the ferrule, that is, an optical fiber insertion hole, and is fitted and fixed to the fixed side insert 7 so as to face the cavity 30 from one end side (right side) of the cavity 30. Has been done. The core pin 9 includes a large diameter portion and a small diameter portion for forming an optical fiber through hole and a guide hole thereof in the ferrule. The diameter of the large diameter portion is 2 mm and the diameter of the small diameter portion is 0.134 mm.

Further, the movable die 120 is provided with a movable die plate 17 which fixedly supports the movable nest 10 and is guided along the guide pins 18, and spacer blocks 20a and 20b for the movable die plate 17. The movable side mounting plate 24 fixed via the ejector guide pin 23 fixed between the movable side template 17 and the movable side mounting plate 24 is movable relative to the movable side template 17. A pair of plate-shaped ejector plate right 21 and ejector plate left 22 are provided. The ejector plate right 21 is provided with a return pin 19, a first ejector pin 15, and a second ejector pin 16. The ejector plate left 22
Moves to the right against the return pin spring 19a when driven by a drive source (not shown) by the push rod 208.

The movable side insert 10 has an annular shape as shown in FIG. 6 and a main runner 5 arranged so as to cross the center thereof.
2B and a runner composed of a sub-runner 52A, a ring gate reservoir 53A, and a ring gate 54A, which are connected to both sides of the main runner 52B with a central straight line portion therebetween, and a ferrule 55 (cavity 30) is formed at the tip thereof. . The ferrule molded body 60 is molded by the runner and the cavity 30.

The first ejector pin 15 is formed in a cylindrical shape, and is slidably inserted into a hole provided to connect the movable mold plate 17 and the movable insert 10 to each other. When the mold of the mold device is closed, a mold member that forms the end face of the ferrule is formed. Further, in the ejecting step after mold opening, it has a function of moving in the axial direction (right direction) of the cavity 30 to release the ferrule molded body 60 from the movable side insert 10. The outer diameter of the first ejector pin 15 is
It is formed to have the same outer diameter as the ferrule.

Similarly, the left end of the second ejector pin 16 is fixed to the ejector plate right 21 and the ejector plate left 22, and the second ejector pin 16 operates left and right together with these. The second ejector pin 16 causes the runner portion of the ferrule molded body 60 to be ejected and released by performing the same operation as the first ejector pin 15.

In order to carry out injection molding of a ferrule by using this mold device, pelletized material of a mixture obtained by mixing and kneading zirconia powder and an organic binder in advance is heated and melted by a heating cylinder, and then moved. Side nesting 1
In the mold closed state in which 0 and the fixed side insert 7 are closed, first, (1) the molten molding material is pressurized on the heating cylinder side, and the sprue 2, the manifold 4, and the hot runner nozzle 6 are directed toward the movable side insert 10. To flow.
At this time, the molten molding material is heated and maintained at a molding temperature of about 150 ° C. to 220 ° C. by the coil heater 40. (2) In this state, the melt molding material is injected into the cavity 30 under pressure through the runner composed of the main runner 52B, the sub-runner 52, the ring gate reservoir 53, and the ring gate 54 to be filled.

(3) After filling, the material is cooled once, (4) After cooling, (5) the mold is opened. That is, when the movable frame 204 of the molding machine 200 is driven to the left by the motor, the movable side mounting plate 24 fixed to the movable frame 204 moves to the left, and the movable die 120 integrally moves to the left. It moves and separates from the fixed mold 110. At this time, the ferrule molded body 60 filled in the injection molding die device 100 is released from the core pin 9 and remains in the movable side insert 10.

Next, (6) the ejecting rod 208 is driven by the motor to move to the right, thereby moving the ejector plate right 21 and the ejector plate left 22 to the right (toward the fixed side). First ejector pin 1 fixed to the ejector plate right 21 and the ejector plate left 22
5. By moving the second ejector pin 16 to the right by 10 to 20 mm, the ferrule molded body 60 is released from the movable side insert 10. That is, the ferrule molded body 60 is released by the first ejector pin 15 protruding the ferrule 55 and the second ejector pin 16 protruding the molded body by the runner to the right. At this time, the return pins 19 fixed to the ejector plate right 21 and the ejector plate left 22 also move to the right at the same time.

After this, (7) when the protruding rod 208 returns to the left, the ejector plate right 21 and the ejector plate left 22 are returned by the return pin spring 19a until they are pressed against the movable side mounting plate 24. At this time, if the return pin spring 19a does not return due to the spring force of the return pin spring 19a, the return pin 19 is fixed when the mold is closed.
The ejector plate right 21 and the ejector plate left 22 are pushed back to the predetermined positions shown in FIG.

Thereafter, (8) when the movable frame 204 is driven by the motor to move to the right, the movable frame 2
The movable side mounting plate 24 fixed to 04 moves to the right, the movable die 120 integrally moves to the right, and the guide pin 8 is inserted into the insertion hole of the guide pin 8 provided in the movable side insert 10. Is inserted, and further abuts against the fixed mold 110 to form the mold closed state again. In this way, the molding cycle described above is repeated.

The molded ferrule 55 is further degreased and sintered. At this time, the binder contained in the ceramic compound material is removed. The sintered ferrule becomes a finished product after processing such as polishing.

The above-mentioned mold device is a device provided with one set of a movable-side insert having two cavities and a fixed-side insert, and when the mold is closed, the guide pin 8 and the movable-side insert provided on the fixed-side insert are attached. The position of the guide pin 8 and the insertion hole was smoothly adjusted only by setting the position of the insertion hole of the provided guide pin.

[0018]

For the efficient production of ferrules, a mold apparatus is provided with four sets of movable-side inserts having two cavities and fixed-side inserts, and eight ferrules are molded at the same time. Alternatively, a so-called multi-cavity mold apparatus has been developed in which four sets of movable-side inserts having four cavities and fixed-side inserts are provided, and 16 injection moldings are performed at the same time. However, in a multi-cavity large-sized mold device, after molding and releasing the ferrule, when forming a mold closed state for the next molding, there are multiple alignment points, so this can be done smoothly all at once. It is difficult to do so that the mold device could not be opened and closed smoothly. If this is forcibly performed, the guide pin may be deformed, the positional relationship between the cavity and the core pin may be broken, and the position of the center through hole of the ferrule may be displaced, resulting in poor dimensional accuracy of the product.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a fixed-side insert and a movable-side insert when forming a mold closed state in a mold apparatus for performing a large number of molds. The mold closing operation can be performed smoothly at the same time, and the opening / closing operation of the entire mold apparatus can be smoothly performed.

[0020]

According to a first aspect of the present invention, there is provided a fixed mold having a plurality of fixed-side inserts, and a movable mold having a plurality of movable-side inserts to which a molding material is supplied via the fixed-side inserts. In a mold apparatus including a mold and a mold including a fixed-side insert and a movable-side insert, a first positioning unit that positions the fixed mold and the movable mold, and a first positioning unit. Positioning means that operates after positioning has been provided, and second positioning means for aligning the fixed side insert and the movable side insert for each set of the fixed side insert and the movable side insert. It is a mold device for injection molding.

According to a second aspect of the present invention, the first positioning means comprises a first pin installed on one of a fixed mold and a movable mold and an insertion hole for receiving the first pin installed on the other, The second positioning means includes a second pin installed on one of the fixed-side insert and the movable-side insert, and an insertion hole that receives the second pin installed on the other, and has a length of the first pin. The mold apparatus for injection molding according to claim 1, wherein the length is longer than the length of the second pin.

According to a third aspect of the present invention, the plurality of fixed-side or movable-side nests are movably arranged on the fixed mold or the movable mold in a direction intersecting with a mold opening / closing direction. It is a mold device for injection molding according to Item 1 or 2.

According to a fourth aspect of the present invention, the fixed mold or the movable mold comprises a mold and a plurality of recesses provided in the mold for accommodating the nests. 4. The injection molding die apparatus according to claim 3, wherein the nest accommodating portion is provided so that a gap is formed between the nest accommodating portion and the accommodated nest in a direction intersecting a mold opening / closing direction. is there.

[0024]

DETAILED DESCRIPTION OF THE INVENTION One embodiment of the present invention will be described below. An embodiment of the present invention is characterized in that in a 16-piece mold apparatus having four nest sets having four cavities, all of the four nest sets can be smoothly aligned when the mold is closed. FIG. 1 is a layout explanatory view of a nest set in a mold apparatus according to an embodiment of the present invention, and FIG. 2 is a spread view of a fixed side nest and a movable side nest of the mold apparatus. The same components as those in FIG. 5 are designated by the same reference numerals.

Referring to FIG. 1, the mold device 100 includes a pair of nests 10 in which a stationary nest and a movable nest are paired.
The form which arrange | positions 1, 102, 103, 104 in 4 places is shown typically. A ceramic compound material is supplied to each set of these nests to form a ferrule molded body. Although FIG. 1 illustrates the movable-side insert placed on the movable template as seen from above, the movable-side insert is separated from and fixed to the fixed-side insert (perpendicular to the plane of FIG. 1). It can move in any direction.

FIG. 2 shows a fixed side nest A and a movable side nest B.
In the mold construction, the pin 38a of the fixed-side insert A is fitted into the insertion hole 38b of the movable-side insert B to form the mold closed state. The pin 38a is a positioning pin for positioning the movable side insert B, and at the same time, the core pin 9 disposed in the fixed side insert A is inserted into the cavity 30 and the tip of the core pin 9 is inserted into the first ejector pin. It has a function as a guide pin to be inserted into a hole 31 a provided at the center of the shaft 31. The pin 38
a is a chamfered or substantially hemispherical guide portion 3 at its tip.
8c is formed. The fixed-side insert A has a ceramic compound material supply hole C communicating with the runner nozzle in the center, and the melted ceramic compound material is supplied from the supply hole C to the central part D of the runner 29 of the movable-side insert B. It Then, through a runner d1 extending in four directions from the central portion D, a semicircular runner d2 that branches further to the left and right is reached, and each tip thereof is a ring gate d3.
Lead to The ceramic compound material is supplied from the ring gate d3 to the cavity 30 (see FIG. 4) to produce a ferrule molded body.

As is apparent from FIG. 2, since four ring gates are formed in the runner 29 and the ceramic compound material is simultaneously supplied from each gate to four cavities, four ferrule molded bodies are simultaneously produced. Further, since the mold apparatus of the present embodiment has such a set of nests at four positions, 16 ferrule molded bodies are simultaneously produced, that is, 1
A six-piece mold device is constructed.

FIG. 3 is a sectional view of the main part of the mold device, and FIG.
It is a partially expanded sectional view. Referring to FIGS. 3 and 4,
The nest alignment will be described. Note that, in FIG. 3, the nest set 101 of FIG. 1 is representatively shown as a fixed side nest A and a movable side nest B.

The injection molding die unit 100 comprises a fixed die 110 fixed to a fixed frame 202 of the molding machine and a movable die 120 fixed to a movable frame 204 of the molding machine 200 which moves in the left-right direction. A positioning pin 48 that guides the movement of the movable die 120 and aligns the movable die 120 with the fixed die 110 is configured to be openable and closable in the left-right direction. These fixed mold 110 and movable mold 120 are shown in FIG.
When the mold is closed, the cavity 30 forming the outer shape of the ferrule and the runner 29 (see FIG. 4) communicating with one end of the cavity 30 are formed between each other. After that, when the movable frame 204 is driven by a motor (not shown) and moves leftward from the state of FIG.
The positioning pin 38a is pulled out from the insertion hole 38b, and then the positioning pin 48 is pulled out from the movable mold plate 17. The moving distance during this is 200 to 250 mm.

In this state, the ferrule molded body filled in the injection molding die device 100 is released from the core pin 9 and remains in the movable side insert B. Next, in the eject step, the ejection rod 20 of the molding machine 200
8 is driven by a motor to operate to the right, and moves the ejector plate right 21 and the ejector plate left 22 to the right (fixed mold direction). Ejector plate right 2
1, the first, second, third, fourth and fifth ejector pins 31, 32 fixed to the ejector plate left 22
By moving 33, 34, and 35 to the right, the ferrule molded body is released from the movable-side insert B. That is, the ejector pins 31, 32, 33, 34, 35 are
The ferrule molded body is released from the movable-side insert B by protruding the ferrule molded body to the right.

Thereafter, the mold closing operation is started and the movable frame 2
When 04 is driven by the motor and moves to the right, the movable side mounting plate 24 fixed to the movable frame 204 moves to the right and the movable side mold plate 17 fixed to the movable mold 120.
Moves to the right integrally, and first, the positioning pin 48 installed on the fixed-side mold plate 5 of the fixed mold 110 is fitted into the insertion hole 48b of the movable mold to insert the first movable mold 120 and the fixed mold 110 into the first mold.
Stage alignment is performed. By this first-stage alignment, the insertion holes 3 provided in the four movable-side inserts B
The movable die 12 is so large that the positioning pins 38a provided upright on the four fixed-side inserts A can be inserted into each of the 8b.
Positioning between 0 and the fixed die 110 is performed.

When the movement is further continued, the positioning pin 3 of the fixed side insert A7 is inserted into the insertion hole 38b of the movable side insert B next.
8a is fitted and the movable side insert B and the fixed side insert A are aligned in each set. Due to this second-stage alignment, the tips of the core pins 9 erected on the fixed-side inserts A are provided with holes 31a in the first ejector pins 31 in the cavity 30 that function as pin catchers.
The positioning is precise enough to be inserted accurately into the.
In order to perform such stepwise positioning, the positioning pin 38 and the positioning pin 48 have the length of the positioning pin 48 longer than the length of the positioning pin 38.

The stationary mold plate 5 is provided with a nest accommodating portion 5a which is a recess for containing the stationary nest A. At this time, the fixed-side mold plate 5 is fixed by sandwiching the fixed-side mold insert A from both sides of the fixed-side mold plate 5 with the bolts 61 installed on the fixed-side mold plate 5 and the bolts 62 installed on the fixed mold mold A.
A gap 63 (FIG. 4) of about 0.02 mm is formed between the wall surface of the nest accommodating portion 5a and the stationary side nest A. Therefore, even though the positioning pins 48 and the insertion holes 48b are positioned between the movable side mold plate 17 and the fixed side mold plate 5, all of the positioning pins 38a of the fixed side inserts A are movable. Each fixed side insert A is movable within the gap 63 so that it can be smoothly inserted into all of the insertion holes 38b of the side insert B. Therefore, the axial center of the four insertion holes 38b of the movable side insert B and the fixed side insert A
Even if the axial centers of the four positioning pins 38a of FIG. 4 do not coincide with each other before the insertion, the guide portions 38c at the tips of the respective positioning pins 38a are guided by contacting with the openings of the insertion holes 38b. The positions of the fixed-side inserts A are automatically finely adjusted so that all the axis centers of are aligned and all of the four positioning pins 38a are fitted into all of the four insertion holes 38b. Therefore, one set of fixed side nest A and movable side nest B
Therefore, the insertion of all the insertion holes 38b and the positioning pins 38a becomes smooth, and the insertion becomes smooth not only in the nest set but also in another nest set.

The production of the ferrule molded body after performing the mold clamping in this way is the same as the technique of the above-mentioned application by the applicant. That is, the molten molding material is pressurized on the heating cylinder side to flow through the sprue 2, the manifold 4 and the hot runner nozzle 6 toward the movable side insert 10. At this time, the molten molding material is the coil heater 40.
The molding temperature is maintained at about 150 ° C to 220 ° C. Then, this molten molding material is pressure-injected into the cavity 30 through the runner to fill it. After the filling, the mold is once cooled, and after cooling, the mold is opened.

According to the present embodiment, in the 16-piece mold device, when the mold closed state is formed, first, the fixed mold 1 is used.
Since the position of the movable mold 120 is aligned with that of the movable mold 120, the position of the fixed mold and the movable mold of each of the nest sets 101, 102, 103, and 104 are aligned. It can be done smoothly. Therefore, the guide pin 8 is not deformed, the positional relationship between the cavity 30 and the core pin 9 is destroyed, and the position of the center through hole of the ferrule manufactured as a product is not displaced.

The positioning pins 38a provided upright on the plurality of stationary inserts A need not all have uniform lengths. For example, one fixed side insert A may be provided with positioning pins 38a of different lengths, and the length of the plurality of positioning pins 38a on one fixed side insert A may be changed stepwise. Good. Specifically, when the fixed-side insert A is viewed from the mold opening / closing direction, the length of the pin may be changed in the order of clockwise or counterclockwise with respect to the center of the fixed-side insert A, or the center may be sandwiched to form a diagonal line. It is possible to make certain things the same length. Also, the positioning pin 38a
May be erected on the side of the movable-side insert B. The positioning pin 48 is also the same. Further, the nest accommodating portion 17a of the movable side mold plate 17 is configured in the same manner as the nest accommodating portion 5a of the fixed side mold plate 5 in the above embodiment, and the movable side nest B is inside the nest accommodating portion 17a. Similar to the nest A, it may be movable by a minute length so that the position can be automatically adjusted.

[0037]

According to the first and second aspects of the present invention, a metal comprising a fixed template having a stationary insert for supplying a molding material and a movable template having a movable insert for supplying a molding material. In the mold device, first, the mold plate having a plurality of sets of nests is positioned, and then the nests are positioned. Therefore, while the positioning accuracy of the fixed-side nest and the movable-side nest is improved, the mold apparatus as a whole is Opening and closing operations can be performed smoothly.
According to the third and fourth aspects of the present invention, when the fixed side insert and the movable side insert are positioned, when the positioning of one is effective, the other becomes loose, so that the mold closing operation of the fixed side insert and the movable side insert is smooth. You can do it.

[Brief description of drawings]

FIG. 1 is a layout explanatory diagram of a set of nests in a mold device according to an embodiment of the present invention.

FIG. 2 is a spread view of a stationary insert and a movable insert of the mold device according to the embodiment of the present invention.

FIG. 3 is a cross-sectional view of a main part of the mold device according to the embodiment of the present invention.

FIG. 4 is a partially enlarged cross-sectional view of the mold device according to the embodiment of the present invention.

FIG. 5 is a sectional view of a main part of a conventional mold device.

FIG. 6 is an explanatory diagram of a runner portion of the mold device and a molded body released from the runner portion.

[Explanation of symbols]

5 ・ ・ Fixed side template, 6 ・ ・ Hot runner nozzle, 7 ・ ・ Fixed side insert, 10 ・ ・ Movable side insert, 17 ・ ・ Movable side template, 2
9 ... Runner, 30 ... Cavity, 31 ... Ejector pin, 38 ... Positioning pin, 48 ... Positioning pin, 63 ...
Gap, 110 ・ ・ Fixed type, 120 ・ ・ Movable type, A ・ ・ Fixed side insert, B ・ ・ Movable side insert

Claims (4)

[Claims] 1. A fixed die having a plurality of fixed side inserts, and a movable die having a plurality of movable side inserts to which the molding material is supplied via the fixed side inserts. In a mold device that forms a mold with a movable side insert, a first positioning means for aligning a fixed mold and a movable mold, and a positioning means that operates after the positioning by the first positioning means operates. And a second positioning means for aligning the fixed side insert and the movable side insert for each set of the fixed side insert and the movable side insert. 2. The first positioning means comprises a first pin installed on one of a fixed mold and a movable mold and an insertion hole for receiving the first pin installed on the other, and the second positioning device. The means includes a second pin installed on one of the fixed-side nest and the movable-side nest, and the second pin installed on the other side.
2. An injection molding die apparatus according to claim 1, wherein said first pin has a length longer than that of said second pin, said insertion hole receiving said pin. 3. The plurality of fixed side or movable side nests,
The mold apparatus for injection molding according to claim 1 or 2, wherein the mold apparatus is movably arranged on the fixed mold or the movable mold in a direction intersecting a mold opening / closing direction. 4. The fixed mold or the movable mold includes a mold and a plurality of recesses provided in the mold for accommodating the inserts. The mold apparatus for injection molding according to claim 3, wherein the mold is provided so that a gap is formed between the received mold and a direction in which the mold is opened and closed.