JP7255233B2 - mold - Google Patents

Description

TECHNICAL FIELD The present invention relates to a mold used for injection molding of resin products, and more particularly to a mold having a insert made of synthetic resin.

A mold is usually used in injection molding for molding a resin product by injection molding. However, this mold is costly to manufacture and is expensive. Therefore, in some cases, the cavity is configured with a synthetic resin insert manufactured by a three-dimensional molding method, and the insert is mounted on the mold main body to perform injection molding (Patent Document 1). According to this three-dimensional modeling method, even inserts with complicated shapes can be formed in a short period of time at low cost. Therefore, the injection molding cost of small-lot products can be considerably reduced.

However, since the insert made of synthetic resin has low strength and rigidity, it is likely to adhere to the mold body due to the injection molding pressure, which is strongly pressed against the surrounding mold body after repeated injection molding. If the insert made of synthetic resin adheres to the mold main body, it takes a considerable amount of time and effort to remove the insert from the mold main body when replacing the insert.

Japanese Patent Application Laid-Open No. 2017-1220

SUMMARY OF THE INVENTION An object of the present invention is to provide a molding die from which a synthetic resin insert can be easily removed even after repeated injection molding, and a method for manufacturing the same.

The gist of the present invention is as follows.

[1] In a mold having a mold body having an insert mounting part and a synthetic resin insert mounted on the insert mounting part, at least one part between the insert mounting part and the insert A mold, characterized in that a metal interposition is provided in the part.

[2] The insert mounting part has an insert mounting hole that is recessed from the front surface of the mold body, and the metal interposition is arranged entirely between the inner surface of the insert mounting hole and the insert. The mold of [1], characterized in that

[3] The metal interposition includes: a bottom plate disposed between the bottom surface of the insert mounting hole and the rear surface of the insert; side peripheral surfaces of the insert mounting hole; The mold of [2], characterized in that it has a side plate arranged between the surface and the side plate.

[4] The mold according to [3], wherein the side plate has a frame shape surrounding the insert.

[5] The mold according to [3] or [4], wherein a plurality of the bottom plates are superimposed.

[6] The mold according to any one of [1] to [5], which has a cooling mechanism for the insert.

[7] The mold according to [6], wherein the cooling mechanism includes cooling water passage holes provided in the metal interposed body.

[8] The cooling mechanism includes a cooling water flow hole provided in the metal interposition, and cooling heat of the metal interposition cooled by cooling water flowing through the cooling water flow hole. The mold of [6], characterized by having a member that transmits to the child.

[9] The mold according to any one of [1] to [8], which has an ejector pin penetrating the insert.

[10] The mold according to [9], wherein the insert is provided with an insertion hole for the ejector pin, and a metal sleeve is provided on the inner peripheral surface of the insertion hole.

[11] The method for manufacturing a mold according to any one of [1] to [10], comprising: molding the insert by a three-dimensional molding method; A method of manufacturing a molding die, comprising a step of mounting the mold on the main body.

In the mold of the present invention, since the metal insert is arranged between the mold main body and the synthetic resin insert, even if the insert adheres to the metal insert, the metal insert Since the body is not affixed to the mold body, the core and the metal interposer can be easily removed from the mold body.

It is a cross-sectional view of the mold according to the embodiment before the mold is closed. FIG. 2 is a view taken along line II-II of FIG. 1; FIG. 2 is a view taken along line III-III in FIG. 1; FIG. 4 is a cross-sectional view of the mold according to the embodiment after the mold is closed; FIG. 4 is a cross-sectional view of the mold according to the embodiment after the mold is closed; FIG. 4 is a cross-sectional view of the mold according to the embodiment after the mold is closed; It is a cross-sectional view of part of the mold according to the embodiment. It is a cross-sectional view of part of the mold according to the embodiment. It is a cross-sectional view of part of the mold according to the embodiment. It is sectional drawing after mold closing of the shaping|molding die which concerns on another embodiment.

Embodiments will be described below with reference to the drawings.

1 to 4 show a mold 1 according to a first embodiment. This mold 1 has a fixed mold 2 and a movable mold 3 .

The fixed mold 2 includes a mold body having a base plate 4 and a base block 5 attached to the base plate 4 on the movable mold 3 side. The fixed mold 2 also has an insert mounting hole 5a as a insert mounting portion recessed in the vicinity of the center of the surface of the base block 5 facing the movable mold 3, and the insert mounting hole 5a is arranged in the insert mounting hole 5a. It has a bottom plate 6 made of metal, a side plate 7 made of metal, and an insert 10 made of synthetic resin. In this embodiment, the bottom plate 6 and the side plate 7 constitute a metal interposed body.

A sprue bushing 11 is provided so as to penetrate the base block 5 , the bottom plate 6 and the insert 10 . A rear end surface of the sprue bushing 11 faces an injection nozzle inlet 8 provided in the base plate 4 .

As shown in FIG. 2, the base block 5 has a square shape in front view in this embodiment, and guide pin insertion holes 13 are provided at four corners thereof. A guide bush 14 is provided on the inlet side of the guide pin insertion hole 13, that is, on the inner peripheral surface of the movable die 3 side.

As shown in FIG. 2, the insert mounting hole 5a has a square shape in front view in this embodiment, but is not limited to this.

The bottom plate 6 is in contact with the hole bottom portion of the insert mounting hole 5a.

The side plate 7 has a rectangular frame shape overlapping the inner peripheral surface (side peripheral surface) of the insert mounting hole 5a. The side plate 7 has an integral frame shape, but may be a combination of two or more parts. The same applies to the side plate 24 of the movable mold 3, which will be described later.

The insert 10 abuts on the side plate 7 at its side surface and abuts on the bottom plate 6 at its rear surface. In this embodiment, the insert 10 is provided with a projection 10b that forms the shape of the molded product at the center of the front surface (the surface on the side of the movable mold 3). The hole 10a opens at the center of the front surface of the projection 10b.

The sprue bushing 11 is inserted through the large-diameter hole portion 5b and the small-diameter hole portion 5c of the base block 5, the hole 6a of the bottom plate 6, and the hole 10a of the insert 10. As shown in FIG.

As in the embodiment shown in FIG. 10, the bottom plate 6 may have no hole 6a and the insert 10 may have no hole 10a. 10, the sprue bushing 11 is arranged between the inserts 10. As shown in FIG. Other configurations in FIG. 10 are similar to those in FIG. 4, and the same reference numerals denote the same parts.

The movable mold 3 has a base plate 20 for the movable mold 3, a cylinder block 21 fixed to the fixed mold 2 side of the base plate 4, and a base block 22 attached to the fixed mold 2 side of the cylinder block 21. . A mold body of the movable mold 3 is composed of the cylinder block 21 and the base block 22 .

The movable mold 3 further includes an insert mounting hole 22a as an insert mounting portion recessed in the center of the surface of the base block 22 facing the fixed mold 2, and an insert disposed in the insert mounting hole 22a. It has a bottom plate 23 and a side plate 24 made of metal for holding an element, an insert 30 made of synthetic resin, an ejector plate 25, an ejector pin 26 projecting from the ejector plate 25, and the like. The bottom plate 23 and the side plate 24 constitute a metal interposed body.

As shown in FIG. 3, in this embodiment, the base block 22 has a square shape when viewed from the front, and guide pins 27 protruding toward the fixed die 2 are provided at the four corners of the base block 22 . The pin 27 can be inserted into the guide pin insertion hole 13 .

The insert mounting hole 22a has a square shape when viewed from the front, but is not limited to this. The bottom plate 23 is in contact with the hole bottom surface of the insert mounting hole 22a. The side plate 24 has a rectangular frame shape overlapping the inner peripheral surface (side peripheral surface) of the insert mounting hole 22a. The insert 30 is in contact with the bottom plate 23 and the side plate 24 .

In this embodiment, the insert 30 is provided with a concave portion 30a for forming the shape of the molded product, and the convex portion 10a of the insert 10 is fitted into the concave portion 30a. Note that the concave portion 30a of the insert 30 and the convex portion 10a of the insert 10 are shapes determined by the shape of the molded product, and therefore are not limited to this. In some cases, the recesses and protrusions are reversed, and in other cases, the recesses and protrusions are mixed.

The ejector plate 25 is arranged within a bore 28 within the cylinder block 21 . In the cylinder block 21, an ejector projection hole of the molding machine and a return spring (not shown) are provided in the base plate 20 and the bore 28, respectively, so as to move the ejector plate 25 forward and backward.

The ejector pin 26 is inserted through holes 22b, 23b and 30b provided in the base block 22, the bottom plate 23 and the insert 30, respectively. The ejector pin 26 has a length such that the tip surface of the ejector pin 26 is flush with the inner surface (cavity surface) of the recess 30a when the ejector plate 25 is at the retraction limit.

The inserts 10 and 30 are manufactured by a three-dimensional modeling method. As a three-dimensional modeling method, any of the powder lamination method in which a light beam such as a laser is irradiated to a layer of resin powder, the photocurable resin method in which a liquid photocurable resin is irradiated with a light beam, and the resin melt extrusion lamination method. method may be adopted.

Although not shown in FIGS. 1 to 4, the bottom plates 6 and 23 and the side plates 7 and 24 are connected by bolts. The assembly of inserts 10, 30, bottom plates 6, 23 and side plates 7, 24 is fixed to base blocks 5, 22 with bolts.

In order to perform injection molding using this mold 1, the mold is closed as shown in FIG. and take out the molded product.

In this molding die 1, metal bottom plates 6, 23 and side plates 7, 24 are provided between synthetic resin inserts 10, 30 and the inner surfaces of mounting holes 5a, 22a of base blocks 5, 22. is interposed therebetween, even if the inserts 10 and 30 are fixed to the bottom plates 6 and 23 and the side plates 7 and 24 by injection molding a number of times, the inserts 10 and 30 are attached to the bottom plates 6 and 24. 23 and the side plates 7, 24 can be smoothly removed from the mounting holes 5a, 22a.

In addition, in this embodiment, bottom plates 6, 23 and side plates 7, 7, 7, 7, 7, 7, 7, 7, 8 are provided as metal interposed bodies between the inserts 10, 30 and the entire inner surfaces of the mounting holes 5a, 22a, ie, all side peripheral surfaces and bottom surfaces. 24 is interposed, the inserts 10, 30 can be made sufficiently smaller than the mounting holes 5a, 22a.

In addition, since the metal interposed body is composed of the bottom plates 6 and 23 and the frame-shaped side plates 7 and 24, the assembly and separation of the two are easy. After removing the bottom plates 6, 23 and the side plates 7, 24 including the inserts 10, 30 from the mounting holes 5a, 22a, the bottom plates 6, 23 and the side plates 7, 24 and the inserts 10, 30 are separated from each other. Separation can also be easily performed.

Although one bottom plate 6 and one bottom plate 23 are used in the above embodiment, two or more bottom plates may be arranged when the thickness of the insert is small. An example is shown in FIG.

In the mold 1A shown in FIG. 5, inserts 10A and 30A are thinner than inserts 10 and 30 shown in FIGS. The size (opening area and depth) of the mounting holes 5a and 22a is the same between the molds 1 and 1A.

In this mold 1A, second bottom plates 6A, 23A are interposed between inserts 10A, 30A and bottom plates 6, 23 (the ejector pin 26 also penetrates the bottom plate 23A). . The total thickness of the insert 10A and the bottom plate 6A is the same as the thickness of the insert 10 (excluding the convex portion 10b), and the total thickness of the insert 30A and the bottom plate 23A is the same as the thickness of the insert 30. are identical.

Other configurations in FIG. 5 are similar to those in FIGS. 1 to 4, and the same reference numerals denote the same parts.

In this way, even if the size of the insert is changed, by increasing or decreasing the number of intervening bodies such as bottom plates and side plates, or by using bottom plates and side plates with different thicknesses (not shown), the , inserts can be attached to the same mold body. In addition, since the thickness of the inserts 10 and 30 can be reduced according to the shape of the molded product, the modeling time in the three-dimensional modeling method can be shortened.

In the present invention, a core cooling mechanism may be provided. One aspect thereof is shown in FIGS.

In the mold 1B of FIG. 6, cooling water passage holes 10w and 30w are provided in inserts 10 and 30, respectively, and water passage holes 6w and 23w are formed in bottom plates 6 and 23 and communicate with the water passage holes 10w and 30w. is provided. The side plates 7 and 24 are also provided with water passage holes 7w and 24w for passage of cooling water, respectively. The base blocks 5 and 22 are provided with water passage holes (not shown) for passing cooling water to the water passage holes 6w, 7w, 23w and 24w of the bottom plate and the side plates. Other configurations in FIG. 6 are the same as in FIG. 4, and the same reference numerals denote the same parts.

In FIG. 7 , cooling water passage holes 33 are provided in the bottom plate 23 , and cooling water is passed through the water passage holes 33 by water passage pipes 34 and 35 passing through the base block 22 and the side plate 24 . In order to cool the insert 30 , a water passage hole 31 extending from the water passage hole 33 to the middle of the thickness direction of the insert 30 is provided so as to communicate with the water passage hole 33 . A partition plate 32 is arranged in the water passage hole 31 to form a U-shaped flow path in the water passage hole 31 . The base end side of the partition plate 32 crosses the inside of the water passage hole 33 . After the cooling water from the water passage pipe 34 hits the partition plate 32 and flows through the water passage hole 31 to the tip side, it makes a U-turn and returns to the water passage hole 33, and from the water passage hole 33 to the water passage pipe 35. leak.

A heat pipe insertion hole 40 extending from the water passage hole 33 to the middle of the insert 30 in the thickness direction is provided so as to communicate with the water passage hole 33 . Most of the heat pipe 41 is inserted into this heat pipe insertion hole 40 . The rear end of the heat pipe 41 is located inside the water passage hole 33 . The base end of the heat pipe 41 is cooled by the cooling water flowing through the water passage hole 33 , cold heat is transmitted to the tip side of the heat pipe 41 , and the insert 30 is cooled.

On the rear surface of the bottom plate 23, openings 36 and 37 for the partition plate 32 and the heat pipe 41 are provided so as to reach the water passage hole 33, and plugs 38 and 39 are attached to the openings 36 and 37. screwed in a watertight manner.

An O-ring 42 is attached to the rear surface of the insert 30 so as to surround the water passage hole 31 and the heat pipe insertion hole 40 .

Bottom plate 23 and side plate 24 are connected by bolts 45 . The insert 30 and bottom plate 23 are attached to the base block 22 by bolts 46 .

In FIG. 8 , a heat conducting member 50 is provided on the insert 30 so as to transmit the cold heat of the bottom plate 23 cooled by the cooling water flowing through the cooling water passage hole 33 to the insert 30 .

The heat-conducting member 50 includes a back plate 51 arranged flush with the rear surface of the insert 30, and a plurality of sink plates 52 erected from the back plate 51 and extending halfway in the thickness direction of the insert 30. and The insert 30 is formed with a recess into which the back plate 51 is fitted and a recess into which the sink plate 52 is inserted during manufacture by the three-dimensional molding method.
The length of the sink plate 52 extending in the thickness direction is appropriately set according to the shape of the concave portion 30a forming the shape of the molded product.

In FIG. 8, the loading/unloading ports 36 and 37 are unnecessary. Other configurations in FIG. 8 are similar to those in FIG. 7, and the same reference numerals denote the same parts.

6 to 8 show the cooling mechanism for the insert 30, the cooling mechanism for the insert 10 is constructed similarly.

In the present invention, since the insert is made of synthetic resin, sliding against the ejector pin 26 may wear the inner peripheral surface of the ejector pin insertion hole 30b. In order to prevent this abrasion, as shown in FIG. Locked.

The above-described embodiment is an example of the present invention, and the present invention may be in a form other than the above.

Reference Signs List 1, 1A, 1B Mold 2 Fixed mold 3 Movable mold 4, 20 Base plate 5, 22 Base block 6, 23 Bottom plate 6A, 23A Second bottom plate 7, 24 Side plate 10, 30 Insert 11 Sprue bush 25 Ejector Plate 26 Ejector pin 32 Partition plate 33 Cooling water passage hole 41 Heat pipe 50 Thermal conduction member

Claims (9)

In a mold having a mold body having an insert mounting portion and a synthetic resin insert attached to the insert mounting portion,
A molding die provided with a metal interposition at least partly between the insert mounting portion and the insert,
Having a cooling mechanism for the core,
The cooling mechanism includes a cooling water flow hole provided in the metal interposition, and a cooling heat of the metal interposition cooled by cooling water flowing through the cooling water flow hole, and transmits cold heat to the core. A mold characterized by having a member for forming a mold. The insert mounting portion is an insert mounting hole that is recessed from the front surface of the mold body, and the metal insert is disposed entirely between the inner surface of the insert mounting hole and the insert. A mold according to claim 1, characterized in that: The metallic intervening body is
a bottom plate disposed between the bottom surface of the insert mounting hole and the rear surface of the insert;
3. The mold according to claim 2, further comprising a side plate disposed between a side peripheral surface of said insert mounting hole and a side peripheral surface of said insert. 4. The mold according to claim 3, wherein said side plate has a frame shape surrounding said insert. 5. The mold according to claim 3, wherein a plurality of said bottom plates are superimposed and arranged. The mold according to any one of claims 1 to 5, wherein the cooling mechanism includes cooling water passage holes provided in the metal interposed body. The mold according to any one of claims 1 to 6 , which has an ejector pin penetrating through said insert. The insert is provided with an insertion hole for the ejector pin,
8. The mold according to claim 7 , wherein a metal sleeve is provided on the inner peripheral surface of said insertion hole. A method for manufacturing a mold according to any one of claims 1 to 8 ,
a step of molding the insert by a three-dimensional modeling method;
A method for manufacturing a mold, comprising a step of mounting the insert and the metal interposer to the mold main body.

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