JPH06344387A - Injection mold, production thereof and surface treatment device thereof - Google Patents

Abstract

PURPOSE:To enable the adaptation of a light alloy excellent in processability by enhancing the durability of an injection mold for molding a molded product by injecting a molten molding material into the cavity thereof by forming an abrasion-resistant layer on the surface of the mold. CONSTITUTION:An abrasion-resistant layer 17 formed by electroless nickel plating is formed at least on the surfaces coming into contact with a molding material of cores 11', 12' composed of an aluminum alloy and the place where the aluminum alloy being a substrate is exposed by injection molding of the abrasion-resistant layer 17 is irradiated with laser beam (r) by a surface treatment device 21 to be locally heated and the irradiated surface is heat-treated to crystallize the electroless nickel plating layer on the irradiated surface without lowering the mechanical strength of the aluminum alloy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection mold for injection molding with a molding material melted in a cavity to form a molded article, a method for producing the same, and a surface treatment apparatus therefor. TECHNICAL FIELD The present invention relates to an injection molding die in which a wear resistant layer is formed to improve durability, a manufacturing method thereof, and a surface treatment apparatus thereof.

[0002]

2. Description of the Related Art Conventionally, for injection molding, a ferrous material is used as a base material, which is composed of a pair of molds for forming a cavity inside, and is filled with molten resin by injection to form a molded article. The mold is known. In this type of injection molding die (hereinafter, also simply referred to as a die), a JIS 7000-based aluminum alloy (ultra super duralumin) is used as a base material of the die. Since aluminum alloy has good machinability such as cutting, it can reduce the die manufacturing cost and the product development period compared to the conventional injection molding die using the iron-based material as the base material, but it does not cause wear. On the other hand, since it has low durability, it cannot be used as a base material for mass production dies, and is mainly applied to trial production dies and base materials for very small-volume production dies. Particularly, in the molding of a reinforced resin to which an inorganic filler such as glass fiber is added, abrasion is remarkable and several thousand shots are the limit of molding.

Therefore, in order to improve the durability of an injection molding die using an aluminum alloy as a base material, for example, the one described in JP-A-56-115236 has been proposed. This injection molding die (hereinafter referred to as a first conventional example) has improved durability by forming a hard alumite film on the surface of a base material made of an aluminum alloy by an anodic oxidation method.

In Japanese Patent Laid-Open No. 63-188022, an injection molding die having improved durability by forming electroless nickel plating on the surface and then heat-treating the electroless nickel plating. (Hereinafter, referred to as a second conventional example).

[0005]

However, in the first conventional example, the anodic oxidation method does not form the hard alumite film at the boundary of the repaired portion of the die by press fitting, but forms a concave step, so that a molded article is formed. However, there is a problem in that it is not possible to satisfy the required transfer accuracy because it is transferred in a convex shape, and the aesthetic appearance is spoiled. Further, it is difficult for the anodizing method to form a hard alumite film on the surface of a fine shape,
For example, there is a problem that it cannot be applied to a mold for forming a textured surface.

In the second conventional example, the electroless nickel plating has good plating coverage and does not have the problem as in the first conventional example, but the electroless nickel plating is generally about 40%.
It is known that the hardness and wear resistance are dramatically improved by annealing at 0 ° C. for several hours.
Since the S7000-series aluminum alloy is a precipitation hardening type alloy by quenching, it has low heat resistance and its mechanical strength remarkably decreases even when heated to about 200 ° C. Therefore, even if electroless nickel plating is formed on the surface of a mold using this aluminum alloy as the base material, the heat treatment reduces the mechanical strength of the base material and the desired hardness and wear resistance cannot be obtained. Durability cannot be improved.

Therefore, the inventions according to claims 1 and 2 are
By forming a wear-resistant layer in which electroless nickel plating is crystallized at a predetermined position on the surface in contact with the molding material, the durability of the mold made of light alloy is improved and it has excellent workability and can be mass-produced. An object is to provide a molding die. Further, the invention according to claims 3 and 4 forms a wear-resistant layer made of electroless nickel plating on the surface in contact with the molding material, and locally heat-treats the wear-resistant layer to form a metal mold. The electroless nickel plating that composes the wear resistant layer is crystallized without lowering the mechanical strength of the mold to improve the durability of the mold made of light alloy, and it is excellent in workability and can be mass-produced at low cost by injection molding. It is an object of the present invention to provide a method for manufacturing a metal mold.

According to the present invention, the surface of the injection molding die is locally heated without being oxidized and the mechanical strength of the base material constituting the die is lowered and the surface thereof is reduced. Enables local heat treatment without oxidation of
An object of the present invention is to provide a surface treatment device for an injection molding die that improves the durability of the die.

[0009]

In order to achieve the above object, the invention according to claim 1 forms an internal cavity, and injection molding is performed by injection-filling a molten molding material into the cavity to form a molded article. A mold for use in which a base material of the mold is made of a light alloy, and a wear resistant layer made of electroless nickel plating is provided on at least a surface of the base material in contact with the molding material. The electroless nickel plating at a predetermined position is crystallized.

The invention according to claim 2 is characterized in that electroless nickel plating in which wear-resistant fine particles are dispersed is formed as the wear-resistant layer. According to a third aspect of the present invention, a base material of an injection-molding die made of a light alloy having a cavity for injection-filling a molten molding material is prepared, and at least the molding material of the base material is prepared. A wear-resistant layer made of electroless nickel plating is formed on the surface in contact with the material, and then a predetermined position of the wear-resistant layer is locally heated to crystallize the electroless nickel plating. .

According to a fourth aspect of the present invention, the wear-resistant layer is locally heated, and nitrogen or an inert gas is blown to a heated portion of the wear-resistant layer. In the invention according to claim 5, a laser beam source for emitting a laser beam, a bendable transmission medium for transmitting the laser beam, and a laser beam emitted from the laser beam source are condensed to form a transmission medium. A condensing unit introduced from one end side, an irradiation head provided on the other end side of the transmission medium for irradiating the surface of a mold for injection molding with a laser beam transmitted by the transmission medium, and a laser beam by the irradiation head. And a gas injection nozzle that blows nitrogen or an inert gas onto the irradiation surface of the injection molding die that is irradiated with.

The invention according to claim 6 is characterized in that the gas injection nozzle is provided integrally with the irradiation head, and the invention according to claim 7 is the laser transmitted by the transmission medium. 9. A collimating means for converting a beam into a parallel beam is provided.
The invention described above includes a visible light emitting means for emitting visible light, and a visible light emitting means for emitting visible light emitted from the visible light emitting means onto an irradiation surface of the injection molding die which is irradiated with a laser beam. It is characterized by being provided.

Here, the light alloy is an aluminum alloy, and the wear resistant particles are particles of SiC, Al ₂ O ₃ , BN, diamond or the like.

[0014]

According to the first aspect of the present invention, a wear resistant layer made of electroless nickel plating is formed on at least the surface of the base material made of a light alloy that is in contact with the molding material, and the electroless nickel plating is crystallized at a predetermined position. It Therefore, the wear resistance is improved by the electroless nickel plating, and the wear resistance of the wear resistant layer at a predetermined position is further improved by the crystallized electroless nickel plating.

In the second aspect of the invention, electroless nickel plating in which wear-resistant fine particles are dispersed is formed as the wear-resistant layer. Therefore, the wear resistance is further improved by the wear resistant fine particles. In the invention according to claim 3,
A wear-resistant layer made of electroless nickel plating is formed on at least the surface of the base material made of light alloy that is in contact with the molding material, and then the heating portion of the wear-resistant layer at a predetermined position is locally heated to cause electroless nickel plating. Is crystallized. Therefore, the electroless nickel plating in the heating portion is locally heat-treated and crystallized without lowering the mechanical strength of the base material.

According to the fourth aspect of the present invention, the abrasion resistant layer is locally heated, and nitrogen or an inert gas is blown to the heated portion of the abrasion resistant layer which is heated. Therefore, the electroless nickel plating is crystallized without being oxidized. In the invention according to claim 5, the laser beam emitted from the laser beam source is condensed by the condensing unit, transmitted by the bendable transmission medium, and irradiated by the irradiation head onto the irradiation surface of the die surface. Further, nitrogen or an inert gas is blown onto the irradiation surface by the gas injection nozzle. Therefore, the irradiation surface of the laser beam is locally heated without being oxidized, the mechanical strength of the base material is not reduced, and the irradiation surface is not oxidized. Heat-treated locally. Further, the position and the irradiation angle of the irradiation surface of the laser beam can be easily changed by the bendable transmission medium.

In the invention according to claim 6, the gas injection nozzle is provided integrally with the irradiation head. Therefore, even if the irradiation head is moved and the irradiation surface of the laser beam is moved, the gas injection nozzle is also moved integrally, so that the irradiation surface of the laser beam is reliably sprayed with nitrogen or an inert gas. According to the invention described in claim 7, collimating means for converting the laser beam transmitted by the transmission medium into a parallel beam is provided. Therefore, since the collimating means collimates the laser beam, the distance to the irradiation surface of the laser beam is not restricted by the focal length of the optical system.

According to the eighth aspect of the present invention, visible light is emitted from the visible light emitting means, and the visible surface of the laser beam is irradiated with the visible light. Therefore,
The irradiation surface of the laser beam is confirmed by visible light.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. 1 to 3 are views showing a first embodiment of an injection molding die, a method for manufacturing the same, and a surface treatment apparatus therefor according to the present invention. This embodiment corresponds to the invention according to claim 1 or 3. ing.

First, the structure of the injection molding die will be described. In FIG. 1, 11 and 12 are nests, and nests 11 and 12 are JIS.
The insert 11 is made of a 7000 series aluminum alloy (light alloy), and has a recess 13 formed in a predetermined concave shape and a groove 14 facing the recess 13, and the insert 12 has a recess 13 of the insert 11 and An opposing surface 15 that faces the groove 14 and has a predetermined surface roughness, and a spool portion 16 that injects the molten resin are provided.
Although not shown, the inserts 11 and 12 are mounted on movable and fixed bases and clamped by an injection molding machine. The cavity (molding space) is defined and the groove
14 and opposing surface 15 define a runner communicating with the cavity.

The inserts 11 and 12 are made by injecting a molten resin (molding material) from the back surface side of the facing surface 14 of the insert 12 into the spool portion 16 by the injection molding machine and inserting the molten resin (molding material) into the cavity through the runner. After the molten resin is injected and filled and cooled to solidify the molten resin, the molten resin is opened by the injection molding machine to form the recess 13
The molded product is taken out from the. That is, the nests 11 and 12 and the movable and fixed bases form a nesting type injection molding die.

The thickness of the plating on the surfaces of the nests 11 and 12 is 5 μm.
Wear-resistant layer 17 (shown in FIG. 3) made of electroless nickel plating is formed.
The durability of 12 is improved. In addition, this wear resistant layer 17
The electroless nickel plating in the portion corresponding to the wear mark B (described later) shown in FIG. 2 is crystallized by locally heating and annealing (heat treatment) by the surface treatment device described later, and the mother of the nests 11 and 12 is crystallized. The durability is further improved without lowering the mechanical strength of the aluminum alloy as a material.

The wear mark B is formed, for example, by using the inserts 11 ', 12' which are not crystallized by the electroless nickel plating forming the wear resistant layer 17 formed on the surfaces of the inserts 11, 12, for example. This is a scratch that is generated along with the wear mark A when the cavity 15 is injection-filled with a polycarbonate resin containing 30 wt% of glass fiber, and as shown in FIG. The wear marks A of fine scratches of 1 μm or less corresponding to the glass fiber diameter and the wear marks B in which the electroless nickel plating of the wear-resistant layer 17 is completely removed and the aluminum alloy as the base material is exposed are found in 15 Will be available. The wear marks A spread radially from the runner facing surface 14 'of the facing surface 15 that faces the groove 14 defining the runner, and the wear marks B correspond to the side ends of the groove 14 and the ends of the wear marks A. A large number of parts, especially wear marks A, are generated at the portions intersecting the side surface of the concave portion 13 at an angle close to a right angle.
Although not shown, the wear marks A and B similarly occur at the portions corresponding to the insert 11 '. Then, if this injection molding is continued, the width of the wear mark B becomes particularly large, and burrs are generated on the molded product after about 6,000 shots, and it is judged that the mold has reached the end of its life.

The wear marks A and B are scratches caused by the abrasive wear caused by the glass fibers scratching the surface under a high molding pressure, and the wear marks B rapidly change the flow direction of the molten resin during injection molding. Because
Occurs where the pressure momentarily rises above the apparent injection molding pressure. Therefore, the abrasion marks A and B are generated in the same place regardless of the density of the glass fiber and the type of the resin material, and the higher the injection molding pressure and the glass fiber density, and the higher the injection molding temperature, the faster the growth. , The mold life will be shortened.

Next, the structure of the surface treatment apparatus will be described. In FIG. 3, reference numeral 21 denotes a surface treatment apparatus. The surface treatment apparatus 21 is, for example, a YAG laser oscillator (wavelength λ = 1.06 μm) that oscillates when excited by a xenon flash lamp and emits a laser beam r (laser beam) of φ4 mm. A laser beam source 22 and a beam expander for converting a thin laser beam r emitted from the laser beam source 22 into a thick parallel beam.
23, a reflection mirror 24 for reflecting the laser light r converted by the beam expander 23 downward, and a condenser lens 25 for condensing the laser light r reflected by the reflection mirror 24. This surface treatment device 21 is, for example, X-
A laser beam r is locally irradiated to a place where a wear mark B of the insert 11 or the insert 12 placed on a Y table (not shown) is generated, and electroless electrolysis is performed at a predetermined position of the wear resistant layer 17. The nickel plating is instantaneously heated to 600 ° C. or more and annealed to crystallize the aluminum alloy, which is the base material of the inserts 11 and 12, without lowering the mechanical strength. That is, the portion where the abrasion mark B is generated becomes the irradiation surface (heating portion) of the laser beam.

The YAG laser oscillator of the laser beam source 22 uniformly irradiates the abrasion resistant layer 17 on the surface with the laser beam r having a high output energy density so as to prevent the aluminum alloy as the base material from being affected by heat. Q of multimode to do
The switch oscillates. The laser beam source 22 is also a CO ₂ gas laser (wavelength λ = 10.6 μ).
m) may be used, but due to the light absorption characteristics of nickel, YA
The G laser is more energy efficient.

Next, the operation will be described. First, the nest 11 in which the recess 13 and the groove 14 are formed and the wear resistant layer 17 is not formed.
Base material 11 "(not shown) and the insert 12 with the facing surface 15 and the spool portion 16 and without the wear-resistant layer 17 formed thereon.
Of the base material 12 "(not shown) are prepared, injection-filled with the polycarbonate resin, and temporary molding is performed to mold the molded product for about 50 shots. Identify the location (irradiated surface) where the mark B occurs,
Record the position. It should be noted that, in the temporary molding for about 50 shots, a portion that is largely scraped does not occur and does not impair the appearance of the molded product, but the location where the wear mark B is generated is the side surface of the concave portion 13 of the scratch of the wear mark A. Can be specified by the angle intersecting with.

Then, the base materials 11 "and 12" are immersed in a nickel chloride bath containing sodium hypophosphite as a reducing agent to deposit nickel, thereby forming a wear resistant layer 17 made of electroless nickel plating on the surface. Create the nested 11'12 '. Then, the insert 11'12 'is placed on the XY table, and the surface treatment device 21 irradiates a laser beam r to the place where the wear mark B of the wear-resistant layer 17 recorded in advance is generated. The inserts 11 and 12 are produced by locally annealing and crystallizing the electroless nickel plating on the irradiation surface.

When the injection molding of the polycarbonate resin was performed using the inserts 11 and 12, the abrasion mark B was obtained even if the number of moldings exceeded 30,000 shots.
No occurrence of scratches was observed, and the aluminum alloy as the base of the wear-resistant layer 17 was exposed at the place where the wear scar A had been generated after the number of shots exceeded 40,000.
Transferred to a molded product with 0 shots. Therefore, the life of the nests 11 and 12 was determined to be 50,000 shots. Therefore, the electroless nickel plating is formed on the surface of the base material 11 "12", and the wear-resistant layer 17 is formed by crystallizing the place where the abrasion mark B of the electroless nickel plating is generated, so that the life of the die is increased. It can be more than doubled.

The electroless nickel plating is an amorphous film, and the hardness after deposition is about Hv500. However, if the deposited amorphous film is annealed at about 400 ° C. (at least 300 ° C. is required) for several hours, nickel is deposited. It is known that a small amount of Ni ₃ -P compound is co-deposited in the crystal phase of and the hardness increases to around Hv 1,000 and the wear resistance is improved. The surface treatment of the wear resistant layer 17 is performed by the X-ray diffraction method. When the electroless nickel plating on the irradiation surface irradiated with the laser beam r was analyzed by the apparatus 21, diffraction lines of Ni and Ni ₃ -P were observed, and it was confirmed that the electroless nickel plating was crystallized.

As described above, according to this embodiment, the wear resistance of the inserts 11 and 12 is improved by the wear resistant layer 17 made of electroless nickel plating formed on the surface of the base material made of the aluminum alloy. The wear resistance of the inserts 11 and 12 is further improved by the crystallized electroless nickel plating on the irradiation surface of the laser beam r corresponding to the wear mark B of the wear resistant layer 17. Therefore, the life of the inserts 11 and 12 can be extended. Therefore, it is possible to provide a low-cost injection molding die that can be mass-produced using the aluminum alloy having excellent workability.

Further, the surface treatment device 21 irradiates the portion corresponding to the wear mark B of the wear resistant layer 17 made of electroless nickel plating formed on the surface of the base material with the laser beam r,
The irradiated surface is locally heated and instantaneously annealed to be crystallized. Therefore, the electroless nickel plating is crystallized and the wear resistance of the wear resistant layer 17 is further improved without lowering the mechanical strength of the base material made of the aluminum alloy, which is the base of the wear resistant layer 17. Therefore, the life of the inserts 11 and 12 can be easily improved in a short time.
Therefore, it is possible to provide a manufacturing method capable of producing an injection molding die which can be mass-produced using the aluminum alloy having excellent workability in a short time at low cost.

In this embodiment, the electroless nickel plating is crystallized only at a predetermined position of the wear resistant layer, but the wear resistant layer having a predetermined area is sequentially heated so that the base material is not thermally affected. The entire wear resistant layer may be crystallized. Next, FIG. 4 is a view showing a second embodiment of the injection molding die according to the present invention, and this embodiment corresponds to the invention described in claim 1 or 2. In this embodiment, the same components as those in the above-mentioned embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the figure, 31 and 32 are nests, and nests are
31 and 32 are configured in the same manner as the inserts 11 and 12 described in the above-mentioned embodiment, and the SiC particles (wear-resistant fine particles) are dispersed on the surfaces of the inserts 31 and 32 and correspond to the wear marks B. A wear resistant layer (not shown) made of crystallized electroless nickel plating is formed. And this nest 31, 32
Molding was carried out by injection-filling the above-mentioned polycarbonate resin using No. 1, but even if the number of moldings exceeded 50,000 shots, no scratches that would deteriorate the quality of the molded product were observed.

In this embodiment, in addition to the effects of the above-mentioned embodiment, the wear resistance is further improved by dispersing the SiC particles in the wear resistant layer. Therefore, the nest 31, 32
The mold life can be extended. In this example, the wear resistance is improved and the die life is extended by dispersing the SiC particles in the electroless nickel plating forming the wear resistant layer. The same effect can be obtained by dispersing particles such as Al ₂ O ₃ , BN or diamond.

Next, FIGS. 5 and 6 are views showing a second embodiment of a method for manufacturing an injection molding die and a surface treatment apparatus therefor according to the present invention. 7
The invention corresponds to any one of the above. In this embodiment, the same components as those in the above-mentioned embodiment are designated by the same reference numerals and the description thereof will be omitted. In FIG. 5, reference numeral 41 denotes a surface treatment apparatus. The surface treatment apparatus 41 is a laser beam source of a YAG laser oscillator that oscillates by, for example, xenon flash lamp excitation and emits a laser beam r (laser beam) of φ6 mm.
42, a bendable quartz optical fiber (transmission medium) 43 having a core diameter of φ8 mm for transmitting a laser beam r, and a laser beam source
A condensing unit 44 that condenses the laser light r emitted from 42 and introduces the laser light r from one end of a quartz optical fiber (hereinafter also simply referred to as an optical fiber) 43, and the other end that is transmitted by the optical fiber 43. The laser beam r emitted from the side
For example, a collimating means 45 which combines a collimating lens and a reduction optical system of a Kepler type composed of two convex lenses and a collimating means 45 for converting into a parallel beam of mm.
The laser beam r converted into a parallel beam by holding
Irradiation head for irradiating the place (irradiation surface) where the wear mark B of the insert 11 or the insert 12 placed on the Y table occurs
46 and a nest that is irradiated with laser light r by the irradiation head 46.
The gas injection nozzle 47 that blows nitrogen gas supplied from a nitrogen gas supply device (not shown) on the irradiation surface of 11 or the insert 12, the output of the laser beam r oscillated by the laser beam source 42 and the gas injection nozzle 47 Control means (not shown) for synchronizing the timing with the injection of the nitrogen gas.

As shown in FIG. 6, the control means inputs the output command signal 51 to the laser beam source 42 and delays Q ₂ by t ₂ seconds.
A laser beam r is emitted by an on signal 52 of the switch, and at the same time as the output command signal 51 of the laser beam r, the gas jet nozzle 47 is controlled to jet nitrogen gas for t ₁ seconds. While the laser light r is irradiating the irradiation surface with the laser light r, nitrogen gas is blown onto the irradiation surface.

In this embodiment, in addition to the effects of the above-mentioned embodiment, the irradiation surface of the abrasion resistant layer 17 corresponding to the abrasion mark B is irradiated with the laser beam r, and the gas ejecting nozzle is ejected by the control means. Since the nitrogen gas is blown onto the irradiation surface in synchronization with the output of the laser light r, the vicinity of the irradiation surface of the laser light r is easily made into an antioxidant atmosphere and locally heated to be heat-treated. Therefore, the electroless nickel plating forming the wear resistant layer 17 can be crystallized without being oxidized. Further, since the emission of the laser light r and the injection of the nitrogen gas are synchronized by the control means, it is not necessary to manually blow the nitrogen gas onto the irradiation surface, and the work is simplified, and the laser light r is irradiated onto the irradiation surface. When it is irradiated, it is surely placed in an antioxidant atmosphere.

Further, since the laser light r is transmitted by the bendable optical fiber 43, the irradiation position and the irradiation angle of the laser light r can be easily changed in accordance with the uneven shape of the recess 13 of the insert 11. . Further, the collimating means 45 collimates the laser light r into a parallel beam, and the wear resistant layer 17 is not focused.
Since it is irradiated on the irradiation surface of, the laser beam is not restricted by the focal length of the laser beam r. Therefore, a wide range of electroless nickel plating forming the wear resistant layer 17 is heat-treated in a short time without adjusting according to the shape of the recess 13 of the insert 11, and is crystallized without accumulating unnecessary heat. .

In this embodiment, nitrogen gas is blown onto the laser light irradiation surface of the abrasion resistant layer, but an inert gas such as He gas may be blown. Next, FIG. 7 is a diagram showing a third embodiment of a surface treatment apparatus for an injection molding die according to the present invention, and this embodiment corresponds to the invention described in any one of claims 4 to 7. There is. In this embodiment, the same components as those in the above-mentioned embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the figure, 61 is a coaxial tube,
The coaxial tube 61 has the optical fiber 43 and the irradiation head 46 interposed therein, and a gas injection nozzle 67 formed in a cylindrical shape so as to blow nitrogen gas from the periphery of the irradiation head 46 onto the irradiation surface of the abrasion resistant layer 17. The irradiation head 46 and the gas injection nozzle 67 that are arranged are formed so as to be integrated. Nitrogen gas is supplied to the gas injection nozzle 67 from a gas supply device (not shown).

In the present embodiment, in addition to the effects of the above-described embodiment, a gas injection nozzle 67 for blowing nitrogen gas onto the irradiation surface of the abrasion resistant layer 17 is arranged around the irradiation head 46, and therefore the irradiation head 46. Even if the laser beam is moved to move the irradiation surface of the laser light r, the gas injection nozzle 67 also moves integrally, and the nitrogen gas is surely blown to the irradiation surface of the laser light r. Therefore, when the irradiation surface is irradiated with the laser light r, the atmosphere is surely kept in the oxidation preventive atmosphere.

Next, FIG. 8 is a diagram showing a fourth embodiment of a surface treatment apparatus for an injection molding die according to the present invention. This embodiment is the invention according to any one of claims 4 to 8. It corresponds.
In this embodiment, the same components as those in the above-mentioned embodiment are designated by the same reference numerals and the description thereof will be omitted. In the figure, 72 is a visible laser beam source, 74 is a dichroic mirror,
The dichroic mirror 74 is a visible laser beam source (eg,
(He-Ne laser oscillator with wavelength λ = 632.8 nm) 72
The laser beam r ′ (visible light) in the visible range emitted from the laser beam source 22 is mixed with the laser beam r emitted from the laser beam source 22, and the laser beam r ′ in the visible range is the laser beam r ′.
At the same time, the irradiation surface of the abrasion resistant layer 17 is irradiated. That is, the visible laser beam source 72 constitutes a visible light emitting means, and the dichroic mirror 74, the optical fiber 43, the condensing unit 44, the irradiation head 46, etc. constitute a visible light irradiation means.

It should be noted that gas injection nozzles 47 and 67 may be provided so as to spray nitrogen gas onto the irradiation surface of the abrasion resistant layer 17. In this embodiment, in addition to the effects of the above embodiment,
As in the third embodiment, the laser light r emitted from the laser beam sources 22 and 42 is collimated by the collimating means 45 so as not to be imaged on the irradiation surface of the abrasion resistant layer 17, so that the irradiation position of the laser light r should be confirmed. However, the irradiation surface can be confirmed by mixing the laser light r ′ in the visible region emitted from the visible laser beam source 72. Therefore, the irradiation position can be easily probed by, for example, a CCD or the like.

[0045]

According to the invention of claim 1, since the wear resistant layer made of electroless nickel plating crystallized at a predetermined position is formed on the surface in contact with the molding material, wear resistance is achieved by the electroless nickel plating. Can improve the
Further, the crystallized electroless nickel plating can further improve the wear resistance of the wear resistant layer at a predetermined position. Therefore, the durability of the mold made of the light alloy can be improved. As a result, it is possible to provide an injection molding die which is excellent in workability and can be mass-produced.

According to the invention of claim 2, since the electroless nickel plating in which the wear-resistant fine particles are dispersed is formed as the wear-resistant layer, the wear resistance can be further improved by the wear-resistant fine particles. The durability can be improved. According to the invention of claim 3, a wear resistant layer made of electroless nickel plating is formed on the surface in contact with the molding material, and then the heating portion at a predetermined position of the wear resistant layer is locally heated. Since the electroless nickel plating is crystallized by using the electroless nickel plating, the wear resistance can be improved by the wear resistant layer made of the electroless nickel plating. It is possible to further improve the wear resistance of the wear resistant layer by crystallizing the electroless nickel plating of the heating portion at a predetermined position without lowering the mechanical strength of the base material. Therefore, the durability of the mold made of a light alloy can be improved in a short time. As a result, it is possible to provide a manufacturing method capable of producing an injection molding die which is excellent in workability and can be mass-produced in a short time at low cost.

According to the invention described in claim 4, since nitrogen or an inert gas is blown to the locally heated heating portion of the wear resistant layer, a gas atmosphere that does not easily oxidize can be obtained, and electroless nickel is used. It can be crystallized at low cost without oxidizing the plating. According to the invention of claim 5, the irradiation surface of the die surface is irradiated with the laser beam, and the gas injection nozzle blows nitrogen or an inert gas onto the irradiation surface. It can be locally heated in an anti-oxidation atmosphere, and can be heat-treated without oxidizing the laser beam irradiation surface to improve durability without lowering the mechanical strength of the light alloy mold. . As a result, it is possible to provide a low-cost surface treatment apparatus for an injection molding die that does not require a vacuum tank or the like. Moreover, since the bendable transmission medium transmits the laser beam, the irradiation position and the irradiation angle of the laser beam can be easily changed in accordance with the uneven shape of the mold surface. As a result, it is possible to provide a surface treatment apparatus for an injection molding die which has a high degree of freedom and can be easily automated.

According to the sixth aspect of the present invention, even if the irradiation head is moved to move the irradiation surface of the laser beam, the gas injection nozzle also moves integrally. An active gas can be blown and an antioxidation atmosphere can be maintained. According to the invention described in claim 7, since the collimating means collimates the laser beam and irradiates it on the irradiation surface, the distance to the irradiation surface of the laser beam is not restricted by the focal length of the optical system. Therefore, the electroless nickel plating formed on the surface of the mold having a complicated uneven shape can be easily crystallized. Moreover, since the irradiation surface is irradiated without squeezing the laser beam, a wide range can be heat-treated in a short time,
It does not reduce the mechanical strength of the die base material without accumulating unnecessary heat.

According to the invention described in claim 8, since the irradiation surface of the laser beam is irradiated with visible light, the irradiation surface of the laser beam can be confirmed by the visible light, and the laser beam is irradiated to a desired position. can do.

[Brief description of drawings]

FIG. 1 is a view showing a first embodiment of an injection molding die according to the present invention, and (a) and (b) are plan views when the die is opened.

FIG. 2 is a partial plan view illustrating the first embodiment.

FIG. 3 is a schematic configuration diagram showing a first embodiment of a surface treatment apparatus for carrying out the method of manufacturing an injection molding die according to the present invention.

FIG. 4 is a view showing a second embodiment of the injection molding die according to the present invention, and (a) and (b) are plan views when the die is opened.

FIG. 5 is a schematic configuration diagram showing a second embodiment of the surface treatment apparatus for carrying out the method of manufacturing an injection molding die according to the present invention.

FIG. 6 is a timing chart for explaining the second embodiment.

FIG. 7 is a configuration diagram of essential parts showing a third embodiment of a surface treatment apparatus for carrying out the method of manufacturing an injection molding die according to the present invention.

FIG. 8 is a schematic configuration diagram showing a fourth embodiment of a surface treatment apparatus for carrying out the method for manufacturing an injection molding die according to the present invention.

[Explanation of symbols]

 11, 12, 31, 32 Insert (mold for injection molding) 13 Recess (cavity) 17 Wear resistant layer (electroless nickel plating) 21, 41 Surface treatment device 22, 42 Laser beam source 43 Quartz optical fiber (transmission medium) ) 44 Condensing unit 45 Collimating means 46 Irradiation head 47, 67 Gas injection nozzle 72 Visible laser beam source (visible light emitting means) 74 Dichroic mirror (visible light irradiating means) B Abrasion mark (irradiated surface) r Laser light (laser) Beam) r'laser light (visible light)

Claims (8)

[Claims] 1. A mold for injection molding in which a cavity is formed and a molding material melted in the cavity is injection-filled to mold a molded article, wherein a base material of the mold is a light alloy. An injection having a wear resistant layer made of electroless nickel plating on at least a surface of the base material in contact with the molding material, and the electroless nickel plating at a predetermined position of the wear resistant layer is crystallized Mold for molding. 2. The injection molding die according to claim 1, wherein electroless nickel plating in which wear-resistant fine particles are dispersed is formed as the wear-resistant layer. 3. A base material of an injection-molding die made of a light alloy having a cavity for injection-filling a molten molding material therein is prepared, and at least a surface of the base material in contact with the molding material is prepared. A mold for injection molding, characterized in that a wear resistant layer made of electroless nickel plating is formed, and then a heating portion at a predetermined position of the wear resistant layer is locally heated to crystallize the electroless nickel plating. Manufacturing method. 4. The injection-molding die according to claim 3, wherein the wear-resistant layer is locally heated and nitrogen or an inert gas is blown to a heated portion of the wear-resistant layer. Manufacturing method. 5. A laser beam source for emitting a laser beam, a bendable transmission medium for transmitting the laser beam, and a laser beam emitted from the laser beam source is condensed and introduced into the transmission medium from one end side. A condensing unit; an irradiation head provided on the other end side of the transmission medium for irradiating the surface of a mold for injection molding with a laser beam transmitted by the transmission medium; and a laser beam irradiated by the irradiation head. A surface treatment apparatus for an injection molding die, comprising: a gas injection nozzle that blows nitrogen or an inert gas onto an irradiation surface of the injection molding die. 6. A surface treatment apparatus for an injection molding die according to claim 5, wherein the gas injection nozzle is provided integrally with the irradiation head. 7. A surface treatment apparatus for an injection molding die according to claim 5, further comprising collimating means for collimating a laser beam transmitted by said transmission medium. 8. A visible light emitting means for emitting visible light, and a visible light emitting means for emitting visible light emitted from the visible light emitting means onto an irradiation surface of the injection molding die irradiated with the laser beam. The surface treatment apparatus for an injection molding die according to claim 5, wherein the surface treatment apparatus is provided.