Coating method, die-casting method, and coating apparatus

Abstract

To provide a coating method that is able to increase a range in which coating can be uniformly performed, when spraying and coating an object with a liquid from a spray nozzle.SOLUTION: A coating method according to the present disclosure includes a coating step of spraying air at a speed higher than a flow speed of a liquid, from an air nozzle 12 provided on an outer periphery of a spray nozzle 11, while spraying and coating an object with the liquid from the spray nozzle 11.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a coating method, a die-casting method, and a coating apparatus.

Background Art

[0002] Patent Document 1 describes a technique for applying a release agent to a die-casting mold by spraying it from a spray nozzle in order to improve the release property between aluminum or an aluminum alloy and the mold.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the technique described in Patent Document 1, the flow rate of the release agent decreases at the outer peripheral portion of the spray nozzle, and the range that can be uniformly coated decreases. Such a problem can occur not only in the scene of applying a release agent to a mold but also in the scene of spraying and applying a liquid to an object.

[0005] The present disclosure has been made in view of the above actual situation, and provides a coating method, a die-casting method, and a coating apparatus capable of increasing the range that can be uniformly coated when spraying and applying a liquid to an object with a spray nozzle.

Means for Solving the Problems

[0006] The coating method according to the present disclosure includes a coating step of spraying air from an air nozzle provided on the outer periphery of the spray nozzle at a speed higher than the flow rate of the liquid while spraying and applying the liquid to an object with the spray nozzle.

[0007] The coating apparatus according to this disclosure comprises a spray nozzle for spraying and coating a target with a liquid, and an air nozzle provided on the outer circumference of the spray nozzle for injecting air at a speed faster than the flow velocity of the liquid. [Effects of the Invention]

[0008] According to this disclosure, a coating method, a die-casting method, and a coating apparatus are available that can increase the area over which a liquid can be uniformly applied when spraying and applying a liquid to a target using a spray nozzle. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view showing the mold release agent application process in a die-casting machine according to an embodiment. [Figure 2] This is a schematic cross-sectional view showing the mold release agent application process in a die-casting machine according to a comparative example. [Figure 3] Figures 1 and 2 are schematic diagrams showing the simulation results of the mold release agent application process in a die-casting machine. [Figure 4] This is a schematic diagram showing the simulation results of the mold release agent application process when the air curtain is changed to a trumpet shape in the die-casting machine shown in Figure 1. [Figure 5] This is a schematic diagram showing the flow near the outlet of the air curtain in Figure 3. [Figure 6] Figure 3 is a schematic diagram showing the flow near the mold. [Modes for carrying out the invention]

[0010] The present invention will be described below through embodiments, but the claims are not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential for solving the problem.

[0011] (Embodiment) Using Figures 1 and 2, an example of a die-casting method according to this embodiment (hereinafter referred to as "this casting method") and a die-casting machine used in this casting method will be explained in comparison with a comparative example. Figure 1 is a schematic cross-sectional view showing the mold release agent application process in this die-casting machine. Figure 2 is a schematic cross-sectional view showing the mold release agent application process in a die-casting machine according to a comparative example.

[0012] This casting method is a method for manufacturing castings and includes a mold release agent application step. While the explanation is omitted, this casting method can sequentially perform steps such as mold clamping, molten metal supply, injection forward, mold opening, and casting removal following the mold release agent application step. Furthermore, the die-casting machine used in this casting method has the necessary components for these steps, except for those required for mold release agent application, which will not be explained. Examples of casting materials used in the die-casting machine 1 include, but are not limited to, aluminum, aluminum alloys, zinc alloys, magnesium alloys, copper alloys, lead alloys, and tin alloys.

[0013] As shown in Figure 1, the die-casting machine 1 used in this casting method has a configuration that allows for the application of a release agent to improve the release properties between the casting material and the die-casting mold 10. Specifically, the die-casting machine 1 is equipped with a spray nozzle 11 for spraying and applying the release agent to the die-casting mold 10. The components of the release agent can be any one that can effectively release the casting material, and it may be water-soluble or oil-based.

[0014] In addition, the die-casting machine 1 is equipped with an air nozzle 12 located on the outer circumference of the spray nozzle 11. The air nozzle 12 is a nozzle that sprays air at a speed faster than the flow velocity of the release agent. The air nozzle 12 is preferably provided in a cylindrical shape on the outer circumference of the spray nozzle 11. The air nozzle 12 may, for example, be configured to include multiple nozzles and a ring-shaped opening, with the nozzle openings of each nozzle evenly distributed within the opening. Also, as shown in Figure 1, the spray nozzle 11 and the air nozzle 12 can be mounted on the same base 13.

[0015] The die-casting mold 10 to which the release agent is sprayed along with air from the air nozzle 12 may be at least one of the one or more fixed molds and one or more movable molds that make up the mold. The other molds may be coated with the release agent by other methods. Furthermore, the fixed mold may be composed of a fixed insert and a fixed main mold, and the movable mold may be composed of a movable insert and a movable main mold. In this case, the target of the release agent spraying will be the fixed insert or the movable insert.

[0016] In a die-casting machine 1 with this configuration, the following release agent application process (hereinafter referred to as "this application process") is performed. This application process involves spraying a release agent onto the die-casting mold 10 using a spray nozzle 11, while simultaneously injecting air from an air nozzle 12 located on the outer circumference of the spray nozzle 11 at a speed faster than the flow velocity of the release agent. In other words, this application process involves spraying a release agent onto the die-casting mold 10 using a spray nozzle 11, while injecting air from an air nozzle 12 located on the outer circumference of the spray nozzle 11 at a speed faster than the flow velocity of the release agent.

[0017] To explain the effects of this coating process, a comparative example will be described. As shown in Figure 2, in the die-casting machine 100 of the comparative example, the application of the release agent is simply done by spraying the release agent from the spray nozzle 11 onto the die-casting mold 10. As a result, in the die-casting machine 100, the kinetic energy decreases due to the nozzle spray characteristics at the outer periphery of the spray area 111r, the flow velocity slows down, and the area over which uniform coating can be achieved decreases. In addition, in the die-casting machine 100, as indicated by the arrows near the outer periphery of the spray area 111r, the release agent eventually spreads out along the die-casting mold 10, resulting in a large amount of wasted release agent.

[0018] In contrast, in this coating process, when spraying and applying a mold release agent to the die-cast mold 10 with the spray nozzle 11, a region 12a of air flowing faster than the flow rate of the mold release agent is generated on the outer peripheral portion of the spray nozzle 11. As a result, in this coating process, a new flow rate can be imparted to the mist of the mold release agent that escaped in the comparative example, and the spray region 11r is made to fit inside the region 12a, that is, the mist is redirected so as to suppress the mist from escaping to the outside. Therefore, in this coating process, the adhesion amount outside the central portion increases compared to the comparative example, and the range in which uniform coating is possible can be expanded, that is, the uniform coating property can be improved.

[0019] And in this casting method, since the mold release agent is uniformly applied in this way, the mold release property is improved, and casting defects such as poor mold release, that is, sticking defects, can be prevented in advance.

[0020] Furthermore, in this coating process, since the adhesion rate of the mold release agent can be improved by the air nozzle 12 as described above, the injection amount required for coating can also be reduced, which also leads to a reduction in the coating time.

[0021] Also, in this coating process, since only air for obtaining the above-described effects is used, it can be said that the running cost in the coating process of the mold release agent hardly increases even when compared with the comparative example. The air nozzle 12 that exhibits the above-described effects can also be referred to as an auxiliary air nozzle for assisting the application of the mold release agent.

[0022] In particular, in this coating process, as illustrated in Figure 1, it is preferable for the air nozzle 12 to spray air parallel to the direction in which the release agent is sprayed from the spray nozzle 11. The direction in which the release agent is sprayed can refer to the direction perpendicular to the spray surface at the tip of the spray nozzle 11, that is, the center of the direction in which the release agent is to be sprayed. In other words, it is preferable for the air nozzle 12 to be arranged to spray air parallel to the direction in which the release agent is sprayed from the spray nozzle 11. As a result, the spray angle of the air nozzle 12 becomes parallel to the direction in which the release agent is sprayed from the spray nozzle 11, and thus it is possible to achieve a flow like the one illustrated in Figure 1, that is, a flow that enables the uniform coating described above. Note that the above spray angle is not limited to this example, and may be any other angle that improves uniform coating performance in relation to other conditions such as the flow rate of the release agent spray.

[0023] Furthermore, in this embodiment, the amount of release agent applied can also be controlled by adjusting the size of the air curtain, that is, the radius of the ring of the air nozzle 12, or by adjusting the airflow velocity within a range faster than the spray velocity of the release agent.

[0024] Next, we will explain the simulation results of the mold release agent application process using fluid analysis software, using Figures 3 to 5. Figure 3 is a schematic diagram showing the simulation results of the mold release agent application process in die casting machine 1 in Figure 1 and die casting machine 100 in Figure 2. Figure 4 is a schematic diagram showing the simulation results of the mold release agent application process when the air curtain is changed to a trumpet shape in die casting machine 1 in Figure 1. Figures 5 and 6 are schematic diagrams showing the flow near the air curtain outlet and near the mold in Figure 3, respectively, as vector representations. However, for convenience, in Figures 5 and 6, the magnitude of the flow velocity is represented by the thickness of the arrows. The direction of the arrows indicates the direction of the flow.

[0025] Figure 3 shows the simulation results for the flow in the die-casting machine 100 without an air curtain, as shown in Figure 2, with the flow velocity A of the spray nozzle 11 set to 30 m / s. Also in Figure 3, the simulation results for the flow in the die-casting machine 1 with a cylindrical air curtain that injects air with flow velocity B (> flow velocity A), with flow velocity A set to 30 m / s and flow velocity B set to 50 m / s. Here, flow velocity B refers to the flow velocity of the air nozzle 12. Furthermore, Figure 3 shows the simulation results for the flow in the die-casting machine 1a, where the speed conditions of the die-casting machine 1 are changed so that flow velocity A > flow velocity B, with flow velocity A set to 50 m / s and flow velocity B set to 30 m / s.

[0026] In die-casting machine 1, when comparing the flow with that of die-casting machine 100, it can be seen that, despite having the same flow velocity A, the flow near the mold 22 is reinforced and the flow velocity increases, resulting in an improved adhesion rate of the release agent to the die-casting mold 10.

[0027] Furthermore, comparing the flow in die-casting machine 1 with that of die-casting machine 1a, it can be seen that the adhesion rate of the release agent to the die-casting mold 10 has improved despite the lower flow velocity A of the release agent. This is presumed to be because, in the outer peripheral area 21 of the release agent flow in die-casting machine 1, outward diffusion is prevented by the airflow compared to the outer peripheral area 21 of the release agent flow in die-casting machine 1a.

[0028] In fact, in die-casting machine 1, as shown by the flow in region 23 near the triangle enclosed by the dashed line in Figure 5, the release agent flows through the area surrounded by the air curtain, indicating that the release agent does not escape to the outside. This shows that the amount of release agent used can be reduced.

[0029] Furthermore, in Figure 6, the central area 24 enclosed by the dashed line shows a uniform flow toward the die-casting mold 10, indicating no turbulence. The area near the mold 22 in Figure 6 also shows no turbulence, suggesting that an improvement in the adhesion rate of the release agent can be expected.

[0030] Furthermore, in order to verify the effect of the cylindrical shape in the air curtain, we also investigated the case in which an air nozzle 12r, which forms a trumpet-shaped air curtain, was applied. A trumpet-shaped air curtain refers to a cone-shaped air curtain in which the outer circumference widens towards the die-casting mold 10.

[0031] Figure 4 shows the simulation results for the flow in die casting machine 1r, where the shape of the air curtain of die casting machine 1 has been changed to a trumpet shape, with flow velocity A set to 30 m / s and flow velocity B set to 50 m / s. Also in Figure 4, the simulation results for the flow in die casting machine 1ra, where the speed conditions of die casting machine 1r have been changed so that flow velocity A > flow velocity B, with flow velocity A set to 50 m / s and flow velocity B set to 30 m / s.

[0032] Comparing the results for die-casting machines 1r and 1ra in Figure 4 with the results for die-casting machines 1 and 1a in Figure 3, it can be seen that using a cylindrical air curtain improves the adhesion rate of the release agent compared to using a trumpet-shaped air curtain.

[0033] <Alternative examples, etc.> The above describes an example of this casting method, but the die-casting machine, the shape of the casting, and the casting material (i.e., the material of the casting) used in this method are not limited to those exemplified. Furthermore, an example was given in which one spray nozzle 11 is arranged on the inner circumference of one air nozzle 12. However, depending on the size of the die-casting mold 10 and the area to be sprayed, such sets of spray nozzles 11 and air nozzles 12 may be arranged side by side. Alternatively, multiple spray nozzles 11 may be arranged on the inner circumference of one air nozzle 12. In addition, an example was given in which air is sprayed from the air nozzle 12, but gases other than air may also be sprayed from the air nozzle 12.

[0034] Furthermore, the embodiments and alternative examples described above can be applied not only to die-casting molds but also to situations where a liquid is sprayed onto an object. In this case, the application method includes a coating step in which, while spraying the liquid onto the object with a spray nozzle, air is injected from an air nozzle located on the outer circumference of the spray nozzle at a speed faster than the flow velocity of the liquid. The coating apparatus used in this case comprises a spray nozzle for spraying the liquid onto the object and an air nozzle located on the outer circumference of the spray nozzle for injecting air at a speed faster than the flow velocity of the liquid. Even in this case, the coating step is more effective if the air nozzle injects air parallel to the direction in which the liquid is sprayed from the spray nozzle.

[0035] It should be noted that the present invention is not limited to the embodiments or alternative examples described above, and can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0036] 1 die-casting machine, 10 die-casting molds, 11 spray nozzles, 12 air nozzles, 13 base

Claims

1. The coating process includes spraying a liquid onto the target using a spray nozzle, while simultaneously injecting air from an air nozzle located on the outer circumference of the spray nozzle at a speed faster than the flow velocity of the liquid. In the coating step, the air nozzle sprays the air parallel to the direction in which the liquid is sprayed from the spray nozzle. Application method.

2. The subject is a die-casting mold, and the liquid is a mold release agent. The coating method according to claim 1.

3. A die-casting method comprising the coating method described in claim 2.

4. A spray nozzle for spraying and applying liquid to a target, An air nozzle is provided on the outer circumference of the spray nozzle, which sprays air at a speed faster than the flow velocity of the liquid, Equipped with, The air nozzle is a coating device that sprays air parallel to the direction in which the liquid is sprayed from the spray nozzle.

5. The object is a die-casting mold, and the liquid is a mold release agent. The coating apparatus according to claim 4.

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