JP2000202840A - Mold for molding lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold for molding a lens without forming a gap between an insert and a slide core even when the mold is opened at an infinitesimal amount during a cooling step to remove a strain of a molding resin compressed in an injecting step. SOLUTION: The mold 1 for molding a lens comprises a pair of angular cams 8a, 8b for opening both slide cores 6a, 6b in association with opening/ closing of the mold 1 in such a manner that ends of the cams 8a, 8b are inserted into through holes 18 formed at the cores 6a, 6b and an oblique surface 20 and a vertical surface 19 are respectively formed in the holes 18. In this case, the cams 8a, 8b are respectively formed with a guide surface 26 slidably brought into contact with the surface 20 to guide the cores 6a, 6b in an opening direction in the case of opening the mold 1, and with a control surface 27 slidably brought into contact with the surface 19 to control movements of the cores 6a, 6b in the opening direction in the case of closing the mold 1 and opening it at an infinitesimal amount S.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for molding a long optical lens.

[0002]

2. Description of the Related Art Conventionally, as this type of lens molding die, for example, as shown in FIGS. 4 and 5, a pair of fixed nests 41 and movable nests 42, and between these two nests 41, 42 are formed. Cavity space 43, a pair of slide cores 45 a and 45 b that can be opened and closed in a direction B orthogonal to the opening and closing direction A of the mold 44, and prevent the slide cores 45 a and 45 b from opening due to the pressure in the cavity space 43. And a pair of locking blocks 46a and 46b
A pair of angular pins 47a, 47b are provided which move the slide cores 45a, 45b in a direction away from each other and open the slide cores 45a, 45b with opening and closing of the slide core 4.

The fixed nest 41 is provided on a fixed-side plate 54, and the movable nest 42 is provided on a movable-side plate 49.
It is provided in. In addition, each of the angular pins 47
a and 47b are locking blocks 46a and 46, respectively.
b. The distal ends of the angular pins 47a, 47b are connected to the respective slide cores 45a, 45a.
The movable side plate 49 is inserted through a slanted hole 48 formed in 5b and further inserted into a hole 50 formed in the movable side plate 49. Further, a first tapered surface 51 is formed on the slide cores 45a, 45b, and the locking blocks 46a, 4
6b is in sliding contact with the first tapered surface 51 and the mold 4
A second tapered surface 52 is formed to move the slide cores 45a and 45b in the closing direction when the cover 4 is closed.

According to this, as shown in FIG.
By closing 4, the movable insert 42 moves in the closing direction together with the movable side plate 49, and the inner peripheral surface of the inclined hole 48 moves in the closing direction while slidingly contacting the outer peripheral surfaces of the two angular pins 47a and 47b. Both slide cores 45a, 4
5b closes, and at this time, the first tapered surface 51 comes into contact with the second tapered surface 52. Thereby, the molding resin (molding material) injected into the cavity space 43 is compressed, and the long optical lens 53 is molded.

Thereafter, in order to remove the distortion of the molding resin compressed in the injection step, the mold 44 is opened by a very small amount S during the cooling step, as shown in FIG. The volume is increasing.

[0006]

However, in the above-mentioned conventional type, as shown in FIG. 5, even when the mold 44 is opened by a minute amount S, the inner peripheral surface of the inclined hole 48 has both the angular pins 47a, 47a. The slide cores 45a and 4b are moved by a small amount S in the opening direction while sliding on the outer peripheral surface of the slide core 45b.
5b are separated and open slightly, so that the fixed nest 41
Between the movable core 42 and the slide cores 45a and 45b, and between the movable insert 42 and the slide cores 45a and 45b, respectively.
There is a problem that a gap W in the opening and closing direction B of the slide cores 45a and 45b is generated, and the molding resin enters the gap W to form burrs.

The present invention provides a lens molding die in which no gap is formed between each insert and the slide core even when the mold is opened by a very small amount in order to remove distortion of the molding material. The purpose is to do.

[0008]

In the molding die for a lens according to the present invention, the tip portions of both angular cams are inserted into through holes formed in both slide cores, and each of the through holes is perpendicular to an inclined surface. A guide surface is formed on each of the angular cams so as to slide in contact with the inclined surface when the mold is opened and to guide both slide cores in the opening direction. In this case, a restricting surface is formed which slides on the vertical surface to restrict the movement of the two slide cores in the opening direction.

According to the present invention, a gap in the opening and closing direction of the slide core is formed between each insert and the slide core even if the mold is opened by a very small amount in order to remove distortion of the molding material. There is no.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is characterized in that a pair of fixed nests and movable nests, a cavity space formed between the two nests, and a direction perpendicular to the opening and closing direction of the mold. A cooling step for removing distortion of the molding material compressed in the injection step, comprising a pair of openable and closable slide cores and a pair of locking blocks for preventing the two slide cores from being opened by pressure in the cavity space; A pair of angular cams are provided in a locking block for moving the slide cores in a direction away from each other with the opening and closing of the mold. The tip of the angular cam is inserted into the through holes formed in both slide cores,
In each of the through holes, an inclined surface and a vertical surface orthogonal to the opening / closing direction of the slide core are formed, and each of the angular cams slides on the inclined surface when a mold is opened to slide both slide cores. A guide surface for guiding in the opening direction, and a regulating surface for regulating the movement of the slide cores in the opening direction by slidingly contacting the vertical surface when the mold is closed and when the mold is opened by a minute amount. It is.

According to this, the following operations are provided.

That is, when the mold is completely opened, the inclined surfaces of the through holes are in sliding contact with the guide surfaces of the angular cam, and both slide cores are guided in the opening direction. When the mold is closed, the vertical surface of the through-hole slides on the regulating surface of the angular cam, and the movement of both slide cores in the opening direction is regulated. Furthermore, even when the mold is opened from the closed state by a small amount to remove the distortion of the molding material, the vertical surface of the through hole is restricted by the angular cam regulating surface as in the case of the closed mold. , The movement of both slide cores in the opening direction is regulated, so that no gap is formed between each insert and the slide core in the opening and closing direction of the slide core.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

As shown in FIGS. 2 and 3, reference numeral 1 denotes a molding die for molding a long optical lens 2, and a pair of fixed nests 3 and movable nests 4, and between these two nests 3 and 4. The formed cavity space 5 and a pair of slide cores 6 a and 6 b that can be opened and closed in a direction B orthogonal to the opening and closing direction A of the mold 1.
A pair of locking blocks 7a, 7b for preventing the slide cores 6a, 6b from opening due to the pressure in the cavity space 5, and separating the slide cores 6a, 6b from each other as the mold 1 is opened and closed. And a pair of angular cams 8a and 8b which are moved and opened.

The fixed nest 3 is provided on the fixed side plate 10, and the movable nest 4 is provided on the movable side plate 11. Also, at the tip of each of the nests 3 and 4, a convex portion 12 projecting between the slide cores 6a and 6b,
13 are formed.

A first tapered surface 14 is formed on the outer surface of each of the slide cores 6a and 6b. The first tapered surface 14 is closer to the movable side plate 11 in the opening direction of the slide cores 6a and 6b. It has spread. Each of the locking blocks 7a and 7b is inclined in the same direction as the first taper surface 14 so as to be slidable on the first taper surface 14 and to close the slide cores 6a and 6b when the mold 1 is closed. A second tapered surface 15 that moves in the direction is formed. In addition, as shown in FIG. 2, the inclination angles α of the first and second tapered surfaces 14 and 15 are each set in a range of 1 ° to 5 °.

The two slide cores 6a, 6b have flange portions 1 projecting in the opening direction of the slide cores 6a, 6b.
7, and a through hole 18 is formed in the flange portion 17. Further, each of the angular cams 8a,
8b are bolts 22 for locking blocks 7a,
7b. Angular cams 8a, 8b
Is inserted into the through hole 18 and further inserted into the hole 23 formed in the movable plate 11. The cross sections of the angular cams 8a and 8b are formed in a rectangular shape, and the shapes of the through holes 18 and the holes 23 are also formed in a rectangular shape according to the angular cams 8a and 8b.

Each of the through holes 18 has a slide core 6
A vertical surface 19 orthogonal to the opening / closing direction B of a and 6b and an inclined surface 20 inclined with respect to the vertical surface 19 are formed. The inside of the inclined surface 20 is the slide core 6a,
6b are inclined in the closing direction and the outer sides are slide cores 6a, 6b.
b is inclined in the opening direction.

Each of the angular cams 8a and 8b is composed of a vertical portion 24 and an inclined portion 25 formed at the tip of the vertical portion 24. The inclined portion 25 has the same direction and the same direction as the inclined surface 20. It is inclined at an angle. As shown in FIG. 2, when the mold 1 is opened, the slide cores 6 a and 6 are in sliding contact with the inclined surface 20 inside and outside the inclined portion 25, respectively.
A guide surface 26 for guiding b in the opening direction is formed.
As shown in FIGS. 1 and 3, when the mold 1 is closed and when the mold 1 is opened by a small amount S, the slide core 6a slides on the vertical surface 19 inside the vertical portion 24. , 6
A regulating surface 27 for regulating the movement of b in the opening direction is formed.

The operation of the above configuration will be described below.

As shown in FIG. 3, when the mold 1 is closed, the two slide cores 6a and 6b close to each other, and the molding resin (an example of molding material) injected into the cavity space 5 is compressed. The long optical lens 2 is formed.
At this time, the movable plate 11 moves in the closing direction,
The distal end of each of the angular cams 8a and 8b
And further inserted into the hole 23. In this state, the vertical surface 19 of the through hole 18 is
8b, the first tapered surface 14 and the second tapered surface 15 abut, so that the movement of the slide cores 6a, 6b in the opening direction is restricted. still,
At this time, the pressure in the cavity space 5 is increased via the first and second tapered surfaces 14 and 15 to both the locking blocks 7 a and 7.
Accepted by b.

Thereafter, in order to remove the distortion of the molding resin compressed in the injection step, the mold 1 is opened by a very small amount S during the cooling step, as shown in FIG. Increase volume. In this case, the movable plate 1
The movement of the minute amount S in the opening direction of the slide core 6 causes the slide core 6 to move.
The first tapered surface 14a of the locking block 7
a, slightly separated from the second tapered surface 15 of 7b,
A gap is formed between the tapered surfaces 14 and 15, and the angular cams 8a and 8b relatively shift in the removal direction by the minute amount S.
Since the vertical surface 19 of 8 is in contact with the regulating surface 27 of the angular cams 8a, 8b, the movement of the slide cores 6a, 6b in the opening direction is regulated.

As a result, the space between the convex portion 12 of the fixed insert 3 and the two slide cores 6a, 6b is kept closed, and the slide cores 6a, 6b are provided between the convex portion 12 and the two slide cores 6a, 6b. Is not formed in the opening / closing direction B. Similarly, the space between the protrusion 13 of the movable nest 4 and the slide cores 6a and 6b is also closed,
A gap in the opening / closing direction B of the slide cores 6a, 6b is not formed between the protrusion 13 and the slide cores 6a, 6b. Therefore, it is possible to prevent a problem that the molding resin enters the gap and becomes a burr.

As shown in FIG. 2, when the mold 1 is completely opened, the vertical portions 24 of the angular cams 8a and 8b are disengaged from the through holes 18 by moving the movable side plate 11 in the opening direction. The inclined portion 25 is pulled out from the hole portion 23 to the through hole 1.
8 relatively. At this time, the slide cores 6a,
The first tapered surface 14 of 6b is used as the locking block 7a,
7b, the inclined surface 20 of the through hole 18 slides on the guide surface 26 of the angular cams 8a, 8b, and the slide cores 6a, 6b are guided in the opening direction. Thereby, both slide cores 6a, 6
b are opened apart from the projections 12, 13 of the nests 3, 4.

[0025]

As described above, according to the present invention, even if the mold is opened by a very small amount in order to remove the distortion of the molding material, the opening and closing direction of the slide core is set between each nest and the slide core. No gap is formed. Therefore, it is possible to prevent a problem that the molding material enters the gap to form burrs.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a molding die according to an embodiment of the present invention, showing a state where the die is opened by a minute amount.

FIG. 2 is a sectional view of the molding die, showing a state in which the die is completely opened.

FIG. 3 is a cross-sectional view of the molding die, showing a state in which the die is closed.

FIG. 4 is a cross-sectional view of a conventional molding die, showing a state in which the die is closed.

FIG. 5 is a cross-sectional view of a conventional molding die, showing a state where the die is opened by a minute amount.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Molding die 3 Fixed nest 4 Movable nest 5 Cavity space 6a, 6b Slide core 7a, 7b Locking block 8a, 8b Angular cam 18 Through hole 19 Vertical surface 20 Inclined surface 26 Guide surface 27 Regulatory surface A Mold opening / closing direction B Opening / closing direction of slide core S Small amount

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masashi Tokumori 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 4F202 AH74 AM33 CA01 CA11 CB01 CK00 CK55

Claims (1)

[Claims] 1. A pair of fixed nests and a movable nest, a cavity space formed between these nests, a pair of slide cores openable and closable in a direction orthogonal to the opening and closing direction of a mold, A pair of locking blocks that prevent both slide cores from opening due to pressure, and in order to remove distortion of the molding material compressed in the injection process, a lens molding die that opens the mold by a small amount during the cooling process. A pair of angular cams, which open by moving the slide cores in a direction away from each other with the opening and closing of the mold, are provided in a locking block, and the tip ends of the angular cams are formed on the slide cores. An inclined surface and a vertical surface perpendicular to the opening / closing direction of the slide core are formed in each of the through holes, and a die is formed in each of the angular cams. A guide surface that slides on the inclined surface when opened and guides both slide cores in an opening direction, and a sliding direction that slides on the vertical surface when the mold is closed and when the mold is opened by a small amount, and the opening direction of both slide cores. A molding die for a lens, wherein a regulating surface for regulating movement to the lens is formed.