JPH09300362A - Mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an inclined hole and to perform mold opening and mold release after an inclined pin is pulled out of a molded product by allowing the inclined pin to obliquely pierce through a cavity space to arrange the same and differnetialing timing allowing a second mold member to advance and retreat from timing allowing the inclined pin to advance and retreat. SOLUTION: A core pin 42 (inclined pin) is allowed to retreat until the front end thereof reaches the position facing to a cavity space 40 and extracted from a molded product 71 to form an inclined hole 72a in the molded product 71. Mold opening is started and a movable core 31 and a fixed core 30 are separated. When mold opening is completed in such a state that the molded product 71 and the resin piece 72 solidified within a runner 23 are left on the side of the movable core 31, an ejector pin is advanced in a mold release state and the molded product 71 and the resin piece 72 are projected. At this time, since the front end of the core pin 42 is detached from the molded product 71, the undercut of the molded product can be extracted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding die for molding a molded product having an oblique hole.

[0002]

2. Description of the Related Art Conventionally, in an injection molding machine, resin is filled in a cavity space of a molding die, the resin is solidified in the cavity space, and then the molding die is opened to form a molded product. It is designed to be taken out. And depending on the shape of the molded product, if the molding die has an undercut that cannot be taken out only by opening the molding die to one side, the angular pin should be used to remove the undercut. Has become.

FIG. 2 is a diagram showing a closed state of a conventional molding die, and FIG.
[Fig. 4] is a mold open state diagram of a conventional molding die. In the figure, 1
Reference numeral 2 denotes a fixed-side template, 13 denotes a movable-side template that is arranged so as to be movable back and forth with respect to the fixed-side template 12, and the fixed-side template 1
2 has a cavity 12a, and the movable mold plate 13 has a core 13a.
Are respectively attached, and in the mold closed state, a cavity space 61 is formed between the cavity 12a and the core 13a.

The cavity space 61 is filled with, for example, a resin melted in a heating cylinder (not shown), and the molded product 62 is obtained by cooling and solidifying the resin in the cavity space 61. You can In this case, the molded product 62 is formed with a hole 63 that extends in a direction different from the mold opening / closing direction as an undercut. And the fixed side template 1
2, an angular pin 15 extending obliquely with respect to the mold opening / closing direction is attached, and the movable side mold plate 13 is provided with the hole 6
Slide piece 14 that can slide in the direction in which 3 extends
Is arranged. Further, the slide piece 14 has a pin guide hole 14a extending obliquely corresponding to the angular pin 15.
Is formed. A play is formed between the angular pin 15 and the pin guide hole 14a.

The slide piece 14 has a lateral hole core pin 1 extending with its front end facing the cavity space 61.
1, and a lateral hole core pin guide piece 16 that guides the lateral hole core pin 11 and defines the forward limit position of the lateral hole core pin 11 when the slide piece 14 is moved to the cavity space 61 side. In the molding die having the above structure, when the movable side mold plate 13 is retracted (moved downward in the figure) when the mold closed state shown in FIG. 2 is changed to the mold opened state shown in FIG. The slide piece 14 moves in the direction of arrow A because it tries to come out while being guided by the pin guide hole 14a. As a result, the lateral hole core pin 11 is also moved in the direction of arrow A and comes out of the hole 63 of the molded product 62.

When the undercut is removed in this manner, the ejector pin (not shown) provided on the core 13a is advanced, and the molded product 62 is ejected to release the mold. In addition, by using the signal of the injection molding machine to operate the hydraulic system etc., to remove the undercut, at the time of mold release,
The undercut can be removed by ejecting the molded product 62 and the placing piece at the same time by the ejector pin and then separating the molded article 62 and the placing piece.

[0007]

However, in the conventional molding die described above, when a wire guide plate of a dot print head or the like is molded, an extremely fine oblique hole for guiding the print wire is formed in the molded product 62. Although it is necessary, since the play between the angular pin 15 and the pin guide hole 14a is large with respect to the diameter (about 0.2 [mm]) of the diagonal hole core pin used to form the diagonal hole, , The accuracy of the diagonal hole becomes low.

Further, in the method of operating the hydraulic system or the like by using the signal of the injection molding machine to remove the undercut, the cost of the injection molding machine increases due to the provision of the hydraulic system or the like. Further, in the method of removing the undercut by ejecting the molded product 62 and the placement piece at the same time with the ejector pin at the time of release, it is necessary to separate the molded article 62 and the placement piece for each shot, which is troublesome. , Productivity will decrease.

According to the present invention, the problems of the conventional molding die can be solved, and the precision of the ultrafine diagonal hole can be increased.
An object of the present invention is to provide a molding die that is low in cost and can improve productivity.

[0010]

To this end, in the molding die of the present invention, the first die member is disposed so as to be movable back and forth with the first die member, and the first die member is in the mold closed state and the mold clamped state. A second mold member that forms a cavity space between the member, a tilting pin that is arranged so as to be able to move forward and backward, and that is arranged so as to obliquely penetrate the cavity space, and the second mold member. And a timing adjusting means for making the timing of advancing and retracting the tilt pin different from the timing of advancing and retracting the tilt pin.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 4 is a perspective view of the wire guide plate according to the embodiment of the present invention, and FIG. 5 is a sectional view taken along line BB of FIG. In the figure, 65 is a wire guide plate for guiding a print wire (not shown),
Reference numeral 66 is an oblique hole formed by penetrating the wire guide plate 65. The diameter d of the diagonal hole 66 is 0.2
The angle θ formed with respect to the normal line extending from the surface of the wire guide plate 65 is about 6 [mm] and 1 [°] 3
It is set to about 8 ['].

Next, the molding die used in this embodiment will be described. 6 is a first diagram showing the operation of the molding die in the embodiment of the present invention, FIG. 7 is a second diagram showing the operation of the molding die in the embodiment of the present invention, and FIG. It is a 3rd figure which shows operation | movement of the shaping die in embodiment. For convenience of explanation, the shape of the molded product 71 is different from the shape of the wire guide plate 65 (FIG. 4).

In the figure, reference numeral 20 denotes a molding die, and the molding die 20 is a movable side which is fixed to a fixed side mold assembly 68 and movable toward and away from the fixed side mold assembly 68. It comprises a mold assembly 69. Further, the fixed side mold assembly 68
Includes a fixed side mounting plate 43 mounted on a fixed platen (not shown), a fixed side template 44 mounted on the fixed side mounting plate 43, and the like. On the other hand, the movable side mold assembly 69
Is disposed so as to face the movable side attachment plate 51 attached to a movable platen (not shown) and the fixed side template 44,
A movable mold plate 39 that forms a cavity space 40 between the movable mold plate 39 and the fixed mold plate 44 in the mold clamping state, and the movable mold plate 39 is supported by the pressure of a resin (not shown).
Plate 37 for preventing the deformation of the plate, a spacer block 49 for mounting the plate 37 on the movable side mounting plate 51,
Ejector plates 47, 48 disposed between the receiving plate 37 and the movable side mounting plate 51 so as to be movable back and forth with respect to the movable side mounting plate 51, and the ejector plates 47, 4
The ejector pins 53, 70 and the like are supported at their rear ends (the left end in the figure) by 8. The ejector pin 53
Passes through the receiving plate 37 and the movable side mold plate 39, and
(Rightward in the drawing), and the front end (right end in the drawing) faces the cavity space 40. Further, the ejector pin 70 penetrates the receiving plate 37 and the movable-side mold plate 39 and extends forward, so that the front end faces the sprue 22.

Further, 21 is arranged at the front end of an injection device (not shown), an injection nozzle for injecting resin, 23 is a runner, 54 is connected to an ejector cylinder (not shown),
An ejector rod that is disposed so as to come into contact with the ejector plate 48, P. L. Is the parting line. In the molding die having the above structure, the movable platen is moved forward (moved to the right in the figure) by a driving means (not shown) such as a hydraulic cylinder or an electric motor, and the movable side mold plate 39 is fixed side as shown in FIG. It is pressed against the mold plate 44 and placed in a mold clamped state. Then, the injection device is moved forward (moved to the left in the figure), and the injection nozzle 21 is brought into contact with the sprue 22. Then, the resin is injected from the injection nozzle 21, and the injected resin passes through the sprue 22 and the runner 23 and is filled in the cavity space 40.

Next, when the resin in the cavity space 40 is solidified, the movable platen is retracted (moved to the left in the figure), and the movable side mold plate 39 is moved as shown in FIG.
Moves away from the fixed-side template 44. At this time, the resin solidified in the cavity space 40, that is, the molded product 71.
Remains attached to the movable side template 39. The resin piece 72 formed by solidifying the resin in the sprue 22 and the runner 23 also remains attached to the movable side mold plate 39.

Subsequently, the ejector cylinder is actuated to move the ejector rod 5 as shown in FIG.
4 and the ejector plates 47 and 48 are moved forward (moved to the right in the figure), the ejector pins 53 and 70 are moved forward, and the molded product 71 and the resin piece 72 are projected and fall. Further, 45 is a positioning guide bush for positioning between the fixed side mold plate 44 and the movable side mold plate 39, and 52 is a front end (right end in the figure) disposed inside the positioning guide bush 45 and a rear end ( (Left edge in the figure)
Is a positioning guide pin which is fixed by the receiving plate 37 and the movable side mold plate 39 and is slidably guided by the positioning guide bush 45. In this embodiment, a thermoplastic resin is used as the resin, but a thermosetting resin can also be used.

Next, when molding the molded product 71,
At the same time, a method of forming the diagonal hole 66 will be described. FIG. 9 shows the first undercut in the embodiment of the present invention.
FIG. 10 is a second explanatory diagram of undercut in the embodiment of the present invention, and FIG. 11 is a third explanatory diagram of undercut in the embodiment of the present invention.

In the figure, 30 is the fixed side mold plate 44.
(FIG. 6) fixed side insert (cavity) as a first mold member, 31 is a movable side insert as a second mold member provided on the movable side mold plate 39. (Core), and the movable side template 39 is a parting line P.P. L.
When the mold is pressed against the fixed-side mold plate 44 and placed in the mold clamping state, a cavity space 40 is formed between the fixed-side insert 30 and the movable-side insert 31.

By the way, a molded product 71 is obtained by filling the cavity space 40 with a resin (not shown) and solidifying the resin.
9 is formed, as shown in FIG.
The cavity space 40 is penetrated at an angle θ corresponding to (FIG. 5), and the core pin 42 as an inclined pin is arranged. Both ends of the core pin 42 are supported by the fixed side insert 30 and the movable side insert 31 so that the core pin 42 is not bent by the pressure of the resin filled in the cavity space 40. ing.

However, the core pin 42 has an oblique hole 66.
Since it is tilted at an angle θ corresponding to, it is also necessary to tilt the bracing part 26 for supporting the core pin 42 on the fixed side insert 30 side, as shown in FIG. Therefore, both ends of the core pin 42 are fixed to the fixed side insert 3
0 and the movable side insert 31 are supported while the mold is opened, the fixed insert 30 is undercut P1.
Will be formed. Further, since the oblique hole 66 formed in the molded product 71 is also inclined, as shown in FIG. 11, when the molded product 71 is ejected by the ejector pin 53 while the core pin 42 is still penetrating the cavity space 40. The undercut P2 is formed on the molded product 71.

Therefore, when the mold is opened, the undercut P1
The core pin 42 so that the undercuts P2 can be removed at the time of mold release.
It is arranged so that it can be inserted and removed freely. FIG. 1 is an enlarged view of a main part showing a mold closed state of a molding die according to an embodiment of the present invention, FIG. 12 is a schematic view showing a mold closed state of a molding die according to an embodiment of the present invention, and FIG. FIG. 15 is an enlarged view of an essential part showing a first mold open state of the molding die in the embodiment of the invention, FIG. 14 is a schematic view showing a second mold open state of the molding die in the embodiment of the invention, FIG. FIG. 6 is an enlarged view of a main part showing a second mold open state of the molding die in the embodiment of the present invention. Note that FIGS. 1 and 15 are enlarged views of the portion C of FIGS. 12 and 14.

In the figure, 30 is a fixed-side insert, 44 is a fixed-side mold plate, 39 is a movable-side mold plate that is disposed so as to be able to come in contact with and separate from the fixed-side mold plate 44. The plate 39 is supported by the receiving plate 37. The reference numeral 31 denotes a movable-side inserter which is arranged to be movable back and forth with respect to the movable-side mold plate 39 and to be brought into contact with and separated from the fixed-side insert 30. The movable-side insert 31 is It is urged toward the fixed side by a spring 33 as a timing adjusting means arranged between the receiving plate 37 and the receiving plate 37.

Reference numeral 52 is a positioning guide pin,
The rear end of the positioning guide pin 52 is fixed to the receiving plate 37, extends through the spring 33 to the front (upward in the drawing), and the front end is slidably arranged in the movable side insert 31. . Therefore, the movable insert 31 is guided by the positioning guide pin 52 and is moved back and forth in the direction perpendicular to the receiving plate 37.

Reference numeral 40 denotes a cavity space formed when the movable insert 31 is brought into contact with the fixed insert 30, and 23 is provided to bring the movable insert 31 into contact with the fixed insert 30. It is a runner that is formed when by the way,
A core pin fixing piece 27 is attached to the receiving plate 37, and a core pin 42 for forming the oblique hole 66 (FIG. 5) is fixed to the core pin fixing piece 27. The rear end 42a of the core pin 42 has the core pin fixing piece 27.
The fixing plate 27a fixes the core pin fixing piece 27 substantially vertically, and extends forward (upward in the drawing) to penetrate the guide portion 29 of the movable side insert 31.

Further, the core pin 42 corresponds to the receiving plate 37.
Is moved back and forth as they move back and forth. Then, the core pin 42 is placed at the forward limit position in the mold clamping state, and at this time, the front end of the core pin 42 extends forward from the guide portion 29, penetrates the cavity space 40, and is further fixed side insert 3.
The zero guide portion 28 can be penetrated. Further, the core pin 42 is placed at the retracted limit position in the mold open state, and at this time, the front end of the core pin 42 faces the cavity space 40.

In this case, the rear end 42a of the core pin 42
Is fixed substantially perpendicularly to the core pin fixing piece 27, while the guide portions 28 and 29 are formed at an angle θ corresponding to the oblique hole 66. Therefore, in the forward limit position, the core pin 42 curves forward from the rear end 42a, extends at the angle θ in the guide portions 28, 29 and the cavity space 40, and the guide portion 28,
Both ends are supported by 29. Therefore, the core pin 42 is formed of, for example, elastic SKH steel having a diameter of about 0.2 mm. Further, a plurality of thin steel materials covered with a pipe can be used as the core pin 42. In that case, the core pin 42 is the molded product 71.
It is possible to prevent sticking to the. In this embodiment, the rear end 42a of the core pin 42 is
Is fixed almost perpendicularly to the core pin fixing piece 27, but it can be slightly inclined.

When the receiving plate 37 is moved forward together with the movable platen (not shown) in the mold closed state, the movable side insert 31 is moved forward together with the receiving plate 37, so that the core pin 42 is placed at the retracted limit position and the cavity is moved. It does not project into the space 40. Next, the movable side insert 31 becomes the fixed side insert 30.
When contacting with, the runner 23 and the cavity space 40 are formed between the movable side insert 31 and the fixed side insert 30, and thereafter, the movable side template 39 is also advanced as the receiving plate 37 is advanced. However, since the movable side insert 31 is in contact with the fixed side insert 30 and does not move forward, the movable side insert 31 is retracted with respect to the movable side mold plate 39 against the biasing force of the spring 33, and the core pin 42 is correspondingly moved. Can be moved forward.

Then, when the receiving plate 37 is further moved forward, the movable side insert 31 is retracted with respect to the movable side mold plate 39, and is disposed on the movable side insert 31 as shown in FIG. The stopper 32 abutted against the receiving plate 37, and the movable side mold plate 3
When 9 comes into contact with the fixed side mold plate 44, the mold clamping force is applied to the stopper 3
It is transmitted to the movable side insert 31 via 2 and the mold is clamped. At this time, the front end of the core pin 42 passes through the cavity 40, the fixed side insert 30 is made to penetrate, and the core pin 42 is placed at the forward limit position. Also, the movable side insert 3
A gap (clearance) 26 is formed between the overhanging portion 31a formed in No. 1 and the overhanging portion 39a formed in the movable side template 39. The stroke S set by the gap 26 between the contact of the movable insert 31 with the fixed insert 30 and the contact of the movable mold plate 39 with the fixed mold plate 44.
The movable side insert 31 is retracted by 1 relative to the movable side template 39.
(Moved downward in the figure).

Next, in this mold clamping state, when a resin (not shown) is injected from the injection nozzle 21 (FIG. 6),
The resin fills the cavity space 40 through the sprue 22 and the runner 23, and surrounds the core pin 42. In this case, since both ends of the core pin 42 are supported by the guide portions 28 and 29, the core pin 42 is prevented from being deformed by the pressure of the resin with which the cavity space 40 is filled.

On the other hand, when the receiving plate 37 is retracted together with the movable platen in the mold open state, first the stopper 32 is separated from the receiving plate 37, and then the movable side mold plate 39 is moved from the fixed side mold plate 44. Leave. At this time, the movable side insert 31
Is placed in contact with the fixed-side insert 30.
As shown in FIG. 5, the core pin fixing piece 27 is retracted as the receiving plate 37 is retracted, and the front end of the core pin 42 is disengaged from the stationary insert 30.

Next, as shown in FIGS. 14 and 15, the core pin 4 is moved until the front end faces the cavity space 40.
When 2 is retracted and comes out of the molded product 71, an oblique hole 71a corresponding to the oblique hole 66 is formed in the molded product 71. Then, the mold opening is started, and the movable side insert 31 and the fixed side insert 30 are separated. At this time, the core pin 4
Since the front end of 2 is disengaged from the stationary insert 30, the undercut of the stationary insert 30 can be removed.

In this way, when the mold opening is completed while the molded product 71 and the resin piece 72 solidified in the runner 23 remain on the movable insert 31 side, in the releasing state,
The ejector pins 53 and 70 are advanced, and the molded product 71 and the resin piece 72 are projected. At this time, since the front end of the core pin 42 is separated from the molded product 71, the undercut of the molded product 71 can be removed.

Here, when the depth at which the core pin 42 enters the fixed-side insert 30 at the forward limit position of the core pin 42 is a and the depth of the cavity space 40 is b, the receiving plate 37 of the receiving plate 37 is shown. Before the stroke S1 becomes 0 after the backward movement is started, the front end of the core pin 42 is moved to the cavity space 4
In order to completely remove from 0, S1 ≧ a + b.

As described above, since the oblique hole 66 can be formed without using the angular pin, the accuracy of the oblique hole 66 can be increased. Further, since the undercut can be removed without operating the hydraulic device or the like, the cost can be reduced. further,
Since it is not necessary to simultaneously eject the molded product and the placing piece by the ejector pin at the time of releasing the mold, the work can be simplified and the productivity can be improved.

By the way, as described above, the core pin 42
When in the forward limit position, the cavity space 40
The inside of the guide portion 2 extends at an angle θ corresponding to the diagonal hole 66.
Both ends are supported by 8, 29. In this case, if the precision of forming the guide portions 28 and 29 is low, the core pin 42 cannot be reliably inserted into the guide portion 28 in the mold clamping state. Therefore, the fixed side nest 30
4 are provided with convex portions 30a, and concave portions 31b are formed at positions corresponding to the convex portions 30a of the movable side insert 31. The positions of the movable side insert 31 and the fixed side insert 30 are fixed by brazing. It is possible to make adjustments.

Moreover, the movable side insert 31 and the fixed side insert 30
The holes are formed in the guide portions 28 and 29 at the same time in a state where they are aligned with each other, that is, in a mold closed state. In addition, in the present embodiment, nine diagonal holes 66 are formed in one wire guide plate 65 (FIG. 4), so that the guide portions 28 and 29 are drilled at nine positions at the same time. Done.

In the present embodiment, the drive means is actuated to move the movable platen forward to move the receiving plate 37 forward, and the timing at which the core pin 42 starts to move forward and backward and the timing to start mold opening / closing are set. The springs 33 are different from each other, but it is also possible to separately provide a driving means for advancing and retracting the core pin 42 so that both driving means can be operated independently.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and these are not excluded from the scope of the present invention.

[0039]

As described in detail above, according to the present invention, in the molding die, the first die member and the first die member are arranged so as to be movable back and forth, and the molding die is in the closed state and the clamped state. 1
A second mold member that forms a cavity space with the mold member, a tilt pin that is arranged so as to be able to move forward and backward, and that is arranged so as to obliquely penetrate the cavity space, and the second mold member. It has a timing adjusting means for changing the timing of advancing and retracting the die member and the timing of advancing and retracting the tilt pin.

In this case, the inclined hole can be formed by the inclined pin, and the mold opening and the mold release can be performed after the inclined pin is removed from the molded product. Therefore, since the undercut can be removed without using the angular pin, the accuracy of the oblique hole can be increased. Further, since it is not necessary to operate the hydraulic device or the like, the cost can be reduced.

Further, since it is not necessary to eject the molded product and the placing piece at the same time by the ejector pin at the time of releasing the mold,
The work can be simplified and the productivity can be improved.

[Brief description of drawings]

FIG. 1 is an enlarged view of essential parts showing a mold closed state of a molding die according to an embodiment of the present invention.

FIG. 2 is a mold closed state diagram of a conventional molding die.

FIG. 3 is a mold open state diagram of a conventional molding die.

FIG. 4 is a perspective view of the wire guide plate according to the embodiment of the present invention.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

FIG. 6 is a first diagram showing the operation of the molding die according to the embodiment of the present invention.

FIG. 7 is a second diagram showing the operation of the molding die according to the embodiment of the present invention.

FIG. 8 is a third diagram showing the operation of the molding die according to the embodiment of the present invention.

FIG. 9 is a first explanatory diagram of undercut in the embodiment of the present invention.

FIG. 10 is a second explanatory diagram of undercut in the embodiment of the present invention.

FIG. 11 is a third explanatory diagram of undercuts in the embodiment of the present invention.

FIG. 12 is a schematic diagram showing a mold closed state of the molding die in the embodiment of the present invention.

FIG. 13 is a first diagram of a molding die according to the embodiment of the present invention.
FIG. 3 is an enlarged view of a main part showing the mold open state of FIG.

FIG. 14 is a second molding die according to the embodiment of the present invention.
FIG. 3 is a schematic view showing the mold open state of FIG.

FIG. 15 is a second part of the molding die according to the embodiment of the present invention.
FIG. 3 is an enlarged view of a main part showing the mold open state of FIG.

[Explanation of symbols]

 20 Molding die 30 Fixed-side insert 31 Movable-side insert 33 Spring 40 Cavity space 42 Core pin 66, 71a Oblique hole 71 Molded product

Claims (3)

[Claims] 1. A first mold member; and a second mold member, which is so arranged as to be movable back and forth, in the mold closed state and the mold clamped state.
A second mold member that forms a cavity space with the mold member, and (c) an inclined pin that is arranged so as to be movable back and forth and that is arranged so as to obliquely penetrate the cavity space.
(D) timing of advancing and retracting the second mold member,
A molding die, comprising: timing adjusting means for changing the timing of advancing and retracting the inclined pin. 2. The timing adjusting means starts the mold opening after retracting the inclined pin and pulling out the front end from the molded product when shifting from the mold clamping state to the mold opening state. Mold for. 3. The molding die according to claim 1, wherein the inclined pin is supported by the first mold member and the second mold member in a mold clamping state.