JP3245248B2 - Die casting apparatus and material supply nozzle used for the apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die casting apparatus for press-fitting a molten material into a mold to form a metal product, and a material supply nozzle suitable for implementing the apparatus.

[0002]

2. Description of the Related Art When a metal product is formed by die casting, a molten metal material such as zinc or magnesium melted in a melting furnace A is plunged into a plunger B as shown in FIG.
Pressing (injecting) into the mold E from the nozzle D by the pressure of the piston C reciprocating inside. The mold E is composed of a fixed mold E1 and a movable mold E2. The molten metal press-fitted from the nozzle D is supplied to the product section G of the movable mold E2 through the spool F of the fixed mold E1. After supplying the molten metal material to the product part G, the nozzle D is separated from the fixed mold E1, and further, after the metal material in the product part G is solidified, the movable mold E2 is separated from the fixed mold E1 to take out the product. Done.

[0003]

In the above-mentioned conventional die casting apparatus, the product O is taken out of the mold E integrally with the spool portion P as shown in FIG. As a finished product, the spool portion P must be removed from the product O, but removing the spool portion P from all the products O that are continuously formed in large numbers is a difficult operation. The removed spool portion P is put into the melting furnace A and is used again as a molten metal material. However, since the molten metal material is once again melted, heat energy is consumed excessively and operating costs are high. Price. In addition, in order to smoothly remove the spool portion P from the mold E, it is necessary to periodically (usually every 25 to 50 shots) apply a release agent to the spool F of the mold E, which lowers operating efficiency. Was the cause. Further, when the molten metal material is pressed into the mold E, the air accumulated in the spool F flows into the product part G and mixes with the molten metal, and the quality is poor such as so-called blistering, bumping, and hot water. Was liable to occur, causing a reduction in product yield. SUMMARY OF THE INVENTION The present invention has been made to solve such problems of the prior art, and it is possible to mold a product having no spool portion, thereby applying a release agent to a mold spool and removing the product spool portion. An object of the present invention is to provide a die casting apparatus capable of eliminating work and remelting work, improving workability, saving labor, improving operation efficiency, and improving yield, and a material supply nozzle used in the apparatus.

[0004]

In order to achieve the above object, a die casting apparatus according to the present invention comprises a fixed die and a movable die, and a die in which a product forming part is formed on a joining surface of each die. , Provided in the mold , extending radially from the center
A runner having an opening formed of a slit or a ring-shaped slit opened in the product molding section and a supply port for the molding material opened outside the mold, and the molding material supplied into the runner is kept in a molten state. A material supply nozzle having a heating means, and a material supply source for melting and sending out the molding material,
Means for communicating the material supply source with a molding material supply port of the material supply nozzle.

[0005] The material supply nozzle of the present invention is a material supply nozzle provided in a die of a die-casting molding apparatus, which has a runner inside, and the product forming of the die is formed at the tip of the runner. Slits that extend radially from the center opening to the part
Alternatively, a nozzle body in which an injection port formed of a ring-shaped slit is formed, and a rear end of the runner opens to the outside as a material supply port, and a heating unit provided along the runner of the nozzle body, Is provided.

[0006]

In the die casting apparatus of the present invention having the above-described structure, the spool existing in the conventional mold is deleted, and the molten material is passed through a material supply nozzle provided in the mold to form a product in the mold of the mold. To supply. That is, the material supply nozzle holds the molding material supplied into the runner in a molten state by the heating means, and press-fits this molten molding material from the injection port into the product molding portion of the mold. When the mold is opened, the product formed by the product forming section of the mold is separated and taken out from the injection port of the material supply nozzle. Therefore, a product having no spool is completed.

[0007]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional side view showing an embodiment of the die casting apparatus of the present invention, FIG. 2 is a sectional side view of a material supply nozzle used in the apparatus, and FIG.
It is a line sectional view. As shown in FIG. 1, the die casting apparatus according to the present embodiment includes a mold 10 having a fixed mold 11 and a movable mold 12, a material supply nozzle 20 embedded in the fixed mold 11, and a melting as a material supply source. Furnace 30 and melting furnace 3
A main part is constituted by a nozzle 40 which communicates the nozzle with the material supply nozzle 20. In the present embodiment, the melting furnace 30
The nozzle 40 and the nozzle 40 have the same structure in order to have compatibility with a conventional die casting apparatus.

The mold 10 has a movable mold 1 with respect to a fixed mold 11.
2 in the direction of the arrow a in the drawing to obtain
12 join and separate. These molds 11 and 12
A product forming portion 13 is formed on the joining surface of the above, and a molten molding material is press-fitted into the product forming portion 13 to form a product having a required shape. The material supply nozzle 20 has a cylindrical nozzle body 21 as shown in FIG. The nozzle body 21 is a cylindrical body 22 embedded in the fixed mold 11.
And the body 23 screwed to the base end of the tubular body 22 are integrally formed. As shown in FIG. 3, a runner 24 having a ring-shaped cross section is formed in the inside of the nozzle main body 21 in the axial direction.
As shown in FIG.

The width D ₁ of the runner 24 in the radial direction is arbitrarily set according to the type of molding material, the overall size of the material supply nozzle 20, and the like, but is preferably set to a size of 2 mm or less. The width D ₁ in the case of a larger dimension than it causes a variation in the temperature distribution in the molding material runner 24, since it may be impossible to maintain uniformity per properties such as viscosity. FIG. 4 is a diagram illustrating an example of the shape of the injection port in the material supply nozzle. The shape of the injection port 24a may be circular in cross section, but is preferably a narrow shape such as a cross shape in cross section as shown in FIG. 5A or a ring shape as shown in FIG. You can prevent dripping. Kinds of the width D ₂ also molding of the injection port 24a, is set arbitrarily based on the injection pressure and the like, preferably 0.15mm~
It is effective to set the range to 0.25 mm. In order to adjust the injection amount, in the case of FIG. 4A, a number of slits extending radially from the center, such as six directions and eight directions from a cross shape, are formed, and in the case of FIG. , The opening area may be increased. On the other hand, the rear end of the runner 24 is a supply port 24 of the molten molding material.
The block 25 is attached to the supply port 24b. The opening surface 25a of the block 25 is formed in a shape corresponding to the shape of the tip of the nozzle 40, and the tip of the nozzle 40 contacts the opening surface 25a to communicate the supply port 24b with the melting furnace 30.

A housing 26 made of a heat insulating material is provided on the outer periphery of the cylindrical body 22 in the nozzle body 21. A hollow portion 26a is formed between the housing 26 and the outer peripheral surface of the tubular body 22, and a coil-shaped external heater 27 is disposed along the runner 24 in the hollow portion 26a. On the other hand, a hollow portion 21 a is also formed in the central shaft portion of the nozzle body 21, and a coil-shaped internal heater 28 is disposed along the runner 24 in this hollow portion 21 a. These heaters 27 and 28 are connected to a power supply 50 provided outside the apparatus, and generate heat by the power from the power supply 50. This heat value can be changed by adjusting the value of the power supplied from the power supply. In the present embodiment, in order to properly control the temperature, the thermocouples 51 and 26 are provided at the distal ends of the hollow portions 21a and 26a (that is, in the vicinity of the injection port 24a).
A power supply 50 is controlled by a control device 52 based on the temperature of the portion.

The tip of the nozzle body 21, that is, the periphery of the injection port 24a is in contact with the product forming portion 13 of the mold 10. Since the product molding section 13 is cooled after being filled with the molding material, heat is exposed from the peripheral portion of the injection port 24a, and the molten molding material in the runner 24 may be solidified. Therefore, in the present embodiment, a heat insulating bush 29 is attached to this portion, and the tip of the nozzle body 21 and the mold 1
The heat insulation performance of the runner 24 is improved by interposing the heat insulating bush 29 between the product forming portion 13 and the zero. The heat insulating bush 29 is formed of a heat insulating material such as ceramic. As shown in FIG. 5, the heat-insulating bush 29 is divided into two bush pieces 29a and 29b, and one heat-insulating bush 29 is completed by overlapping these bush pieces 29a and 29b.
With this configuration, expansion and contraction due to heating or cooling are allowed in the overlapped portion 29c, and damage to the heat insulating bush 29 is prevented. In addition, the shape of the heat insulating bush 29 is arbitrary, and can be divided into three or more bush pieces.

Next, the operation and operation of the die casting apparatus having the above-described configuration will be described. The molten molding material such as zinc and magnesium melted in the melting furnace 30 is supplied to the plunger 3.
The pressure is fed to the nozzle 40 by the pressure of the piston 32 which reciprocates within 1. The nozzle 40 contacts the block 25 of the material supply nozzle 20 and communicates with the runner 24 formed in the material supply nozzle 20. Therefore, the nozzle 40
Is supplied from the supply port 24b of the material supply nozzle 20 to the runner 24 and reaches the injection port 24a. Here, since the runner 24 is heated by the heat from each of the heaters 27 and 28, the molding material can be passed in a molten state without a temperature drop.

The molten molding material reaching the injection port 24a is pressed into the product molding section 13 of the mold 10 to form a product having a predetermined shape. Since the molten molding material is heated in the material supply nozzle 20 until immediately before being pressed into the product molding section 13, it can be smoothly injected at a low injection pressure without an increase in viscosity. Thereafter, the movable mold 12 moves in the direction of the arrow a in the figure, the mold 10 is opened, and the product is taken out. At this time, since the product is separated from the injection port 24a of the material supply nozzle 20, there is no spool P as in the conventional product (see FIG. 8). FIG. 6 shows an example of a product formed by the apparatus of this embodiment. Since the product O thus formed does not have the spool portion P, the operation of removing the spool portion is not required, and the heat energy required for the re-melting process of the spool portion can be reduced. Further, the operation of applying the release agent to the mold spool F in the conventional apparatus (see FIG. 7) is not required, and the product O without the spool portion P can be quickly taken out of the mold 10 and the moving efficiency is remarkably improved. Improved.

The nozzle 40 is kept fixed in contact with the block 25 of the material supply nozzle 20 during operation of the apparatus. The runner 24 of the material supply nozzle 20 is filled with the molding material supplied in the previous cycle, and the molding material is maintained in a molten state by the heat of the heaters 27 and 28. The molten molding material in the runner 24 is pressed into the product molding section 13 of the mold 10 in the next cycle. For this reason, air does not mix into the runner 24 during operation, and a high-quality product can be formed stably. According to experiments by the present inventors, as a result of molding a product having the same shape and dimensions by using the conventional apparatus and the apparatus according to the present embodiment, the apparatus according to the present embodiment has about 1.5 times the hardness and about 1.5 times the hardness of the conventional apparatus. 2.1
Double the tensile strength, increase the weight by 3-5% (i.e., increase the density by 3-5%), and reduce the surface grain size by 1/3
１ ／ 1/5 fine product could be obtained. It should be noted that the present invention is not limited to the above-described embodiment, and various modifications or applications are possible without changing the gist. For example, as the heating means, an electromagnetic induction heater may be used in addition to the heating wire heater.

[0015]

As described above, according to the present invention, a product having no spool portion is formed, thereby making it possible to apply a release agent to a mold spool, remove the product spool portion, and re-dissolve the product. Thus, workability can be improved, labor can be saved, operation efficiency can be improved, and product yield can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional side view of an embodiment according to a die casting apparatus of the present invention.

FIG. 2 is a sectional side view of a material supply nozzle used in the apparatus.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a front view showing an example of a shape of an injection port in a material supply nozzle.

FIG. 5 is a front view showing a configuration of a heat insulating bush.

FIG. 6 is a diagram showing an example of a product formed by the apparatus of the present invention.

FIG. 7 is a cross-sectional side view showing a conventional die casting apparatus.

FIG. 8 is a view showing an example of a product formed by a conventional apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Die 11 Fixed mold 12 Movable mold 13 Product forming part 20 Material supply nozzle 21 Nozzle body 22 Cylindrical body 23 Body 24 Runner 24a Injection port 24b Supply port 25 Block 26 Housing 27 External heater 28 Internal heater 29 Heat insulating bush 30 melting furnace 40 nozzle

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akio Yamazaki 4-51-7, Midori-ku, Midori-ku, Yokohama-shi, Kanagawa Prefecture (72) Inventor Takeshi Yamazaki 5-34-3, Higashihongo, Midori-ku, Yokohama-shi, Kanagawa (56) Reference Literature Jpn. 4-66090 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B22D 17/02

Claims (2)

(57) [Claims] 1. A mold comprising a fixed mold and a movable mold, wherein a product molding portion is formed on a joining surface of each mold, and a slit provided in the mold and extending radially from a center.
A runner having an injection port formed of a slit or a ring-shaped slit opened to the product molding section and a supply port of the molding material opened outside the mold, and a heating device for maintaining the molding material supplied in the runner in a molten state. A material supply nozzle having means, a material supply source for melting and sending out a molding material, and a means for communicating the material supply source with a molding material supply port of the material supply nozzle. Die casting equipment. 2. A material supply nozzle provided in a mold of a die-casting molding apparatus, having a runner therein, the tip of the runner being radiated from a center opening to a product molding portion of the mold. A slit that extends
A nozzle body in which an injection port formed of a ring-shaped slit is formed, and a rear end of the runner opens to the outside as a material supply port, and a heating means provided along the runner of the nozzle body, A material supply nozzle in a die casting apparatus, comprising: