spray device

Abstract

To provide a spray apparatus which can uniformly and securely spray a liquid on the inside of a mold in a die cast machine.SOLUTION: A spray apparatus comprises: a spray nozzle 4 for spraying a liquid on a mold; and an outer fitting member 5 fitted therewith. The spray nozzle is provided with: a liquid jet passage 6 having an opened tip to allow the passage of a liquid pumped from a liquid feed passage 1; and a first gas jet passage 7 having an opened tip to allow the passage of a gas pumped from a first gas feed passage 2. The outer fitting member is provided with a second gas jet passage 8 having an opened tip to allow the passage of the gas pumped from a second gas feed passage 3, ensuring the gas jetted from the second gas jet passage collides against a mist flow released from the spray nozzle.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a spray device that sprays atomized liquid onto a mold of a die casting machine.

Background Art

[0002] Casting performed by a die casting machine, in which a molten aluminum alloy or the like is injected into a mold at high speed and high pressure for molding, is widely used in the production of various industrial products because of its excellent productivity and dimensional accuracy. When using such a die casting machine, in order to facilitate mold release when taking out a molded product from the mold, it is necessary to spray a release agent on the inner surface of the mold before molding in advance, or to temporarily cool the mold that has become high temperature during molding, so cooling water is sprayed on the inner surface of the mold before molding.

[0003] When spraying a liquid such as a release agent or cooling water onto the inner surface of the mold as described above, for example, as disclosed in Patent Documents 1 and 2, a method is used in which a liquid supplied from a liquid supply source and a gas supplied from a gas supply source are pressure-fed to a spray nozzle, and the liquid and the gas are mixed and sprayed.

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Patent Document 2

[0005] However, when using a spray nozzle that simply mixes and sprays a liquid and a gas, as shown in Patent Documents 1 and 2, the following problems may occur. One is that when spraying liquid onto a mold that has reached a high temperature, if the particle size of the sprayed mist is large relative to the temperature of the mold, the liquid in contact with the surface of the mold will form a vapor film, resulting in the so-called Leidenfrost phenomenon, which hinders heat conduction to the mold surface and ultimately prevents the mold from being properly cooled. Conversely, if the particle size of the sprayed mist is small relative to the temperature of the mold, the liquid may evaporate before reaching the mold, or the spray stream may diffuse, preventing an appropriate amount of liquid from reaching the mold, and ultimately preventing the mold from being properly cooled. Another problem with spray nozzles that simply mix and spray liquid and a gas is that, for example, if there are protruding parts such as weight-reducing cutouts or casting pins on the inner surface of the mold, the sprayed liquid may not hit these protruding parts uniformly, which may result in the release agent not being properly applied or the cooling by the cooling water being insufficient. [Overview of the project] [Problems that the invention aims to solve]

[0006] Therefore, the present invention aims to provide a spray device that can uniformly spray liquid onto a mold, regardless of the particle size of the liquid sprayed onto the mold, and even when there are protruding parts on the inner surface of the mold, in order to solve the above problems. [Means for solving the problem]

[0007] To solve the aforementioned problems, the present invention provides a spray device for spraying atomized fluid onto a die of a die-casting machine, wherein the spray device comprises a liquid supply passage for pressurizing a liquid supplied from a liquid supply source, a first gas supply passage and a second gas supply passage for separately pressurizing gases supplied from a gas supply source, a spray nozzle for mixing the liquid pressurized from the liquid supply passage and the gas pressurized from the first gas supply passage and spraying the mixture, and a second gas supply passage provided so as to cover at least the outer circumference of the tip of the spray nozzle and pressurized from the second gas supply passage. The spray nozzle is provided with an outer fitting member that ejects gas to the outside, and the spray nozzle has a liquid ejection passage with an open tip that allows liquid pumped from the liquid supply passage to pass through, and a first gas ejection passage with an open tip that allows gas pumped from the first gas supply passage to pass through, and the outer fitting member has a second gas ejection passage with an open tip that allows gas pumped from the second gas supply passage to pass through, and the gas ejected from the second gas ejection passage is made capable of colliding with the spray stream released from the spray nozzle.

[0008] Furthermore, the present invention relates to a spray device for spraying atomized liquid onto a die-casting machine mold, wherein the spray device comprises a liquid supply passage for pressurizing liquid supplied from a liquid supply source, a first gas supply passage and a second gas supply passage for separately pressurizing gases supplied from a gas supply source, a spray nozzle for mixing the liquid pressurized from the liquid supply passage and the gas pressurized from the first gas supply passage and spraying it, and an outer fitting member provided to cover at least the outer circumference of the tip of the spray nozzle, wherein the spray nozzle The spray nozzle is characterized by having a liquid ejection passage with an open tip through which liquid pumped from the liquid transport passage passes, and a first gas ejection passage with an open tip through which gas pumped from the first gas transport passage passes, and a second gas ejection passage with an open tip through which gas pumped from the second gas transport passage passes, in a (circumferential) gap formed between the spray nozzle and the outer fitting member, and by being able to cause the gas ejected from the second gas ejection passage to collide with the spray stream released from the spray nozzle.

[0009] Furthermore, it is desirable that the second gas ejection passage in the present invention has its opening end formed in an inclined shape toward the inside. [Effects of the Invention]

[0010] According to the present invention, by making it possible to collide the spray stream released from the spray nozzle with gas ejected from a second gas ejection passage, the spread of the spray stream is suppressed, and the spray stream can be delivered appropriately and precisely to the targeted area of ​​the mold. Therefore, for example, if the sprayed liquid is a release agent, the release agent can be uniformly applied to the mold, and if the sprayed liquid is cooling water, the mold can be reliably cooled. Furthermore, even if there are protruding parts on the inner surface of the mold, the liquid can be sprayed evenly onto the mold. [Brief explanation of the drawing]

[0011] [Figure 1] Side view of a die-casting machine. [Figure 2] A schematic diagram illustrating the installation of the spraying device. [Figure 3] Side cross-sectional view of the spray nozzle and outer fitting member. [Figure 4] Plan view of the spray nozzle and outer fitting component. [Figure 5] A schematic diagram illustrating the collision of a second gas with a spray stream. [Figure 6] A side cross-sectional view of the spray nozzle and outer fitting member according to the second embodiment. [Modes for carrying out the invention]

[0012] Embodiments of the present invention will be described below with reference to the drawings. The present invention relates to a spray device for spraying atomized liquid onto a die-casting machine mold. This spray device is generally composed of a liquid supply passage 1 for pressurizing liquid W supplied from a liquid supply source, a first gas supply passage 2 and a second gas supply passage 3 for separately pressurizing gas A supplied from a gas supply source, a spray nozzle 4 for mixing and spraying the liquid W pressurized from the liquid supply passage 1 and the gas A1 pressurized from the first gas supply passage 2, and an outer fitting member 5 provided so as to cover at least the outer circumference of the tip of the spray nozzle 4 and for ejecting the gas W2 pressurized from the second gas supply passage to the outside. Furthermore, the spray nozzle 4 of the spray device in this embodiment has a liquid ejection passage 6 with an open tip that allows liquid W supplied under pressure from the liquid supply passage 1 to pass through, and a first gas ejection passage 7 with an open tip that allows gas A1 supplied under pressure from the first gas supply passage 2 to pass through, and the outer fitting member 5 has a second gas ejection passage 8 with an open tip that allows gas A2 supplied under pressure from the second gas supply passage 3 to pass through. Since the spray device according to the present invention is assumed to be installed in a die-casting machine, the configuration of the die-casting machine M in this embodiment will be briefly described first.

[0013] Figure 1 is a schematic diagram of the die-casting machine M according to this embodiment, and the die-casting machine M is generally configured as follows. For the sake of clarity regarding the positional relationship, the left side of Figure 1 will be described as the front side of the die-casting machine M, and the right side of Figure 1 will be described as the rear side of the die-casting machine M. In this die-casting machine M, a fixed platen 11, a movable platen 12, and a rear platen 13 are erected on a base 10 at predetermined intervals. Specifically, the fixed platen 11 is positioned towards the front of the die-casting machine M, the movable platen 12 is positioned approximately in the center of the die-casting machine M, and the rear platen 13 is positioned towards the rear end of the die-casting machine M. Tie bars 14 are stretched between the four corners of the fixed platen 11 and the movable platen 12 to connect them, and tie bars 15 are stretched between the four corners of the movable platen 12 and the rear platen 13 to connect them. Furthermore, a sliding plate 16 is interposed between the lower ends of the fixed platen 11 and the movable platen 12 and the base 10 to slidably support the movable platen 12. In addition, a fixed mold 17 is fixed to the inner surface of the fixed platen 11, and a movable mold 18 is fixed to the inner surface of the movable platen 12. A toggle link 19 is provided between the movable platen 12 and the rear platen 13, and this toggle link 19 is capable of moving the movable platen 12 closer to or further away from the fixed platen 11 by a hydraulic cylinder. In other words, this toggle link 19 allows the movable mold 18 fixed to the movable platen 12 to be moved, thereby enabling so-called mold clamping and mold opening.

[0014] On the other hand, an injection mechanism 20 is formed from the fixed mold 17 to the front of the die-casting machine M. Specifically, a molten metal sleeve 21 is formed to penetrate the lower end of the fixed platen 11 and the fixed mold 17, in the center in the left-right direction. The front end of the molten metal sleeve 21 protrudes forward of the fixed platen 11, and a hot water inlet 21a is opened on its upper surface. Furthermore, an injection cylinder 22 is connected to the front end of the injection sleeve 20, and a plunger rod 24 with an injection plunger 23 at its tip is provided inside the injection cylinder 22. The injection plunger 23 is slidable inside the injection cylinder 22, pressurizing molten metal such as aluminum alloy supplied into the injection sleeve 22 from the hot water inlet 21a of the injection sleeve 22, and injecting it between the fixed mold 17 and the movable mold 18, which are in a clamped state.

[0015] Furthermore, a robot 30 is positioned at the upper end of the fixed platen 11. This robot 30 is provided with a link member 32 that is rotatably connected to a support part 31, and a spray holder 34 is attached to this link member 32 via an arm 33. Multiple spray devices S, which will be described later, are fixed to the tip of the spray holder 34. When the movable mold 15 is open relative to the fixed mold 14, the link member 32 and arm 33 of the robot 30 move the spray holder 34 to a predetermined position between the fixed mold 14 and the movable mold 15, thereby allowing the spray devices to spray liquid onto appropriate locations on the inner surfaces of the fixed mold 14 and the movable mold 15.

[0016] Next, the spray device S provided in the die-casting machine M described above will be explained. Figure 2 is a schematic diagram of the installation of the spray device according to this embodiment. As shown in Figure 2, the liquid supply passage 1 for pressurizing liquid, the first gas supply passage 2 for pressurizing the first gas, and the second gas supply passage 3 for pressurizing the second gas exist separately and independently, and each supplyes its respective liquid and gas. Specifically, the liquid supply passage 1 is connected to a tank 40 as a liquid supply source on its upstream side and to a spray nozzle 5 on its downstream side. The tank 40 contains liquids such as mold release agents and cooling water. The liquid supply passage 1 is also equipped with a flow meter 41, a solenoid valve 42, and a needle valve 43, in that order from the upstream side. On the other hand, the gas flow path 44 is connected to the factory air 45, which serves as a gas supply source, on its upstream side. This is then branched into a first gas delivery path 2 and a second gas delivery path 3. The first gas delivery path 2 is connected to a spray nozzle 4 on its downstream side, and the second gas delivery path 3 is connected to an external fitting member 5 on its downstream side. A pressure regulator 46, a flow rate detection device 47, and a solenoid valve 48 are provided in order from the upstream side of each of the first gas delivery path 2 and the second gas delivery path 3. In this embodiment, the second gas delivery path 3 is further branched into two flow paths on its downstream side and connected to the external fitting member 5. Incidentally, by making the liquid delivery path 1, the first gas delivery path 2, and the second gas delivery path 3 independent, there is the advantage that the flow rate and pressure of the liquid and gas in each delivery path can be set independently.

[0017] As shown in Figures 3 and 4, the spray nozzle 4 is a cylindrical member made of metal, with a narrower diameter at its tip (a narrow-diameter section 50) and an end fitting member 51 with the same diameter as the central section fixed to the other end (upstream end). A through-type liquid ejection passage 6 is formed in the axial center of the spray nozzle 4. Furthermore, the liquid ejection passage 6 has an opening at its tip (downstream end), which serves as the liquid discharge port 52, while the other end (upstream end) of the liquid ejection passage 6, the end fitting member 51, has a connecting portion 53 for connecting to the aforementioned liquid supply passage 1. The downstream end of the liquid supply passage 1 is connected to the connecting portion 53, and the liquid pumped from the tank 40 is supplied to the liquid ejection passage 6 via the liquid supply passage 1, and finally ejected from the liquid discharge port 52. Furthermore, a first gas ejection passage 7 is formed in a circular shape, that is, surrounding the outer circumference of the liquid ejection passage 6, at a position slightly outward from the liquid ejection passage 6. In addition, the tip (downstream end) of the first gas ejection passage 7 is open, and this opening portion serves as the first gas discharge port 54. On the other hand, the other end (upstream end) of the first gas ejection passage 7 is interrupted in front of the end fitting member 51. Furthermore, a connecting portion 55 is formed on the outer surface of the spray nozzle 4, slightly upstream from the axial center, for connecting to the aforementioned first gas supply passage 2. The downstream end of the first gas supply passage 2 is connected to the connecting portion 55, and air A1 pressurized from the factory air 45 is supplied to the first gas ejection passage 6 via the first gas supply passage 2, and then ejected from the first gas discharge port 54. The liquid ejected from the liquid outlet 52 and the air A1 ejected from the first gas outlet 54 mix together immediately after ejection to form a mist, which is then sprayed in a roughly conical shape that spreads in the direction of ejection.

[0018] The externally fitted member 5 is a cylindrical member formed of the same metal as the spray nozzle 4, and is fixed to the small-diameter portion 50 of the spray nozzle 4. Specifically, the externally fitted member 5 is formed in a donut shape with a penetrating circular hole drilled in the central portion, and the circular hole is fitted onto the small-diameter portion 50 of the spray nozzle 4. Further, a second annular gas ejection passage 8 is formed at a position slightly inward from the outer circumference of the externally fitted member 5. Furthermore, the tip (downstream end) of the second gas ejection passage 8 is open over the entire circumference, and this opening serves as a discharge port 60 for the second air A2. On the other hand, connecting portions 61 for connecting to the aforementioned second gas feed passage 3 are formed at two locations on the other end side (upstream end) of the second gas ejection passage 8. The downstream end of the second gas feed passage 3 is connected to the connecting portions 61, so that the air A2 pressure-fed from the factory air 45 is supplied to the second gas ejection passage 8 via the second gas feed passage 3 and ejected from the gas discharge port 60. In this embodiment, the tip side of the second gas ejection passage 8 is inclined inward, so that the air A2 is ejected slightly inward from the gas discharge port 60. In addition, the upper surface of the externally fitted member 5 and the upper surface of the aforementioned spray nozzle 4 are substantially flush, that is, substantially coplanar.

[0019] As shown in Figure 5, with the spray device configured as described above, the liquid ejected from the liquid outlet 52 of the spray nozzle 4 and the air A1 ejected from the first gas outlet 54 mix together to form a spray stream. This spray stream is then sprayed in a roughly conical shape that expands as it moves in the discharge direction. At this time, air A2 is also ejected simultaneously from the second gas outlet 54 of the outer fitting member 5. Since the second gas ejection passage 8 is inclined, the air A2 is ejected inward and collides with the outer circumference of the spray stream ejected from the spray nozzle 4. Therefore, even if the particle size of the sprayed mist is large relative to the mold temperature, the particle size of the mist is further refined by bombarding it with air A2 again, thus eliminating the problem caused by the so-called Leidenfrost phenomenon. Furthermore, the air A2 that collides with the spray stream continues to travel in a straight line, acting as a wall of air. Additionally, because the second gas outlet 54 of the outer fitting member 5 is circumferential, the air A2 ejected from it surrounds the entire circumference of the spray stream after the collision. Therefore, this spray device suppresses the unnecessary spread of the spray stream and ensures that the required amount of liquid with the appropriate particle size is reliably sprayed onto the mold. In other words, if the sprayed liquid is a release agent, it can be uniformly applied to the mold. If the sprayed liquid is cooling water, it can reliably cool the mold. Moreover, even if there are protruding parts on the inner surface of the mold, the liquid can be sprayed evenly onto the mold.

[0020] Fig. 6 shows a second embodiment of the present invention. The spray device according to the second embodiment differs from the aforementioned embodiment in the configurations of the spray nozzle, the outer fitting member, and the second gas ejection passage. Specifically, the spray nozzle 70 in this embodiment is formed of a cylindrical base end portion 71 and a cylindrical protruding portion 72 that protrudes outward (in a direction perpendicular to the axial direction) from the outer peripheral surface on the distal end side of the base end portion 71. Further, an outer fitting member 73 formed of a cap-shaped cylindrical body is fitted onto the outer peripheral surface of the protruding portion 72 of the spray nozzle 70. It is the same as the aforementioned embodiment that an end fitting member 74 having the same diameter as the base end portion 71 is fixed to the upstream end of the base end portion 71 of the spray nozzle 70, that a liquid ejection passage 75 is formed in the axial center of the spray nozzle 70, the distal (downstream end) opening of the liquid ejection passage 75 serves as a liquid discharge port 76, that a connecting portion 77 for connecting to the liquid supply path 1 is formed on the end fitting member 74, and that an annular first gas ejection passage 78 is formed at a position slightly spaced outward from the liquid ejection passage 75. On the other hand, the outer peripheral surface on the distal end side of the protruding portion 72 of the spray nozzle 70 is formed in a tapered shape, and a connecting portion 79 for connecting to a second gas supply path is formed on the other end side of the protruding portion 72. Further, the inner peripheral surface on the distal end side of the outer fitting member 73 is formed in a tapered shape so as to face the outer peripheral surface of the protruding portion 72 of the spray nozzle 70. A gap, that is, a space is formed between the outer peripheral surface of the protruding portion 72 of the spray nozzle 70 and the inner peripheral surface on the distal end side of the outer fitting member 73, and this space serves as a second gas ejection passage 80 that allows the gas pressure-fed from the second gas supply path 3 to pass through. Further, the distal (downstream) end of the second gas ejection passage 80 is open over the entire circumference, and this opening serves as a discharge port 81 for the second air A2. Forming the second gas ejection passage 80 between the spray nozzle 70 and the outer fitting member in this manner has the advantage that these structures can be simplified.

[0021] In the two embodiments described above, the second gas outlet was shown to be circumferential, that is, open all the way around. However, if a relatively large number of openings are to be formed, it is not necessarily required to be circumferential. Also, in the two embodiments described above, the second gas outlet was shown to be inclined inward. However, if the second gas outlet is located close to the liquid outlet and the first gas outlet, for example, it is not necessarily required to be inclined inward. [Explanation of Symbols]

[0022] 1. Liquid supply path 2. First gas supply path 3. Second gas supply path 4. Spray nozzle 5. External fitting member 6 Liquid spout path 7. First gas outlet 8. Second gas outlet 70 spray nozzles 73 External fitting member 75 Liquid spout path 78 First gas outlet 80 Second gas outlet

Claims

1. In a spray device that sprays atomized liquid onto the mold of a die-casting machine, The spray device comprises a liquid supply passage for pressurizing a liquid supplied from a liquid supply source, a first gas supply passage and a second gas supply passage for separately pressurizing gases supplied from a gas supply source, a spray nozzle for mixing the liquid pressurized from the liquid supply passage and the gas pressurized from the first gas supply passage and spraying it, and an outer fitting member provided to cover at least the outer circumference of the tip portion of the spray nozzle. The spray nozzle has a liquid ejection passage with an open tip through which liquid pumped from the liquid supply passage passes, and a first gas ejection passage with an open tip through which gas pumped from the first gas supply passage passes. A second gas ejection passage is formed in the circumferential gap between the spray nozzle and the outer fitting member, with its tip opening to allow the gas pumped from the second gas supply passage to pass through. A spray device characterized in that the gas ejected from the second gas ejection passage can be made to collide with the spray stream released from the spray nozzle.

2. The spray device according to claim 1, characterized in that the opening end of the second gas ejection passage is formed in an inclined shape toward the inside.

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