Foam plastic and its molding equipment, production method, and insulation device

Abstract

The present invention relates to a foam plastic and its molding equipment, production method and heat preservation device. The foam plastic molding equipment and foam plastic molding method are provided with a circulation cavity in the molding die. During foam molding, a circulating high-temperature liquid is introduced into the circulation cavity through a liquid circulation device to quickly heat the molding die, so that the surface of the plastic particles is quickly plasticized and molded at high temperature. In addition, since the surface of the molding cavity is smooth, the surface of the foam plastic crust can form a mirror-smooth effect.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic foaming, in particular to a foam plastic and its molding equipment, manufacturing method and heat-insulating device. Background Art

[0002] Currently, takeout thermal boxes often use foam plastics, such as EPP (expanded polypropylene), as insulation. However, the sidewalls of these boxes have a visible foam plastic particle structure, resulting in an uneven surface that can retain dirt after prolonged use. Gaps between the particles within the boxes can easily trap moisture, which can transfer the temperature inside the box to the outside world, reducing insulation effectiveness and hindering internal cleaning. Summary of the Invention

[0003] Based on this, it is necessary to provide a foam plastic and its molding equipment, production method, and insulation device to solve the problem of the uneven surface of the foam plastic.

[0004] A foam plastic molding device includes a molding mold and a liquid circulation device. The molding mold has a molding cavity and a circulation cavity. The surface of the molding cavity for foam plastic skinning is smooth. The liquid circulation device includes a circulation pipe and a liquid storage tank, a circulation pump and a heater connected to the circulation pipe. The circulation pipe is connected to the circulation cavity to form a liquid circulation loop.

[0005] In one embodiment, the forming mold includes a male mold and a female mold, the male mold and the female mold cooperate with each other to form the forming cavity, and the flow cavity is provided in the female mold.

[0006] In one embodiment, the male mold is made of a breathable metal, and the surface of the male mold used for the foam plastic skin is smooth.

[0007] In one embodiment, the pore size of the permeable metal is 10 μm to 1000 μm.

[0008] In one embodiment, the material of the die is aluminum or aluminum alloy.

[0009] In one embodiment, the foam plastic molding equipment further includes an air extraction device, which is connected to the molding cavity.

[0010] In one embodiment, the foam plastic molding equipment also includes a material tank and a feeding mechanism, the feeding mechanism includes a feeding pipe, a material gun and a boosting component, one end of the feeding pipe is connected to the discharge port of the material tank, the other end of the feeding pipe is connected to the material gun, the material gun is connected to the molding chamber, and the boosting component is arranged near the discharge port of the material tank and is connected to the feeding pipe.

[0011] A method for producing foam plastics, using the foam plastics molding equipment of any of the above embodiments, the method comprising the following steps:

[0012] adding raw materials of foam plastic into the molding cavity;

[0013] Steam is introduced into the molding cavity to pressurize and heat it, and a high-temperature liquid is circulated in the circulation cavity through the liquid circulation device to further heat the molding die, so that the raw material of the foam plastic is foamed and molded, wherein the temperature of the high-temperature liquid is 180° C. to 200° C.;

[0014] Cool and demould.

[0015] In one embodiment, during the foaming process, the air pressure in the molding cavity is controlled to be 10 kg / cm. 2 ~14kg / cm 2 .

[0016] In one embodiment, the thermal conductivity of the high-temperature liquid is 0.3 W / mK to 0.6 W / mK.

[0017] A foam plastic, characterized in that it is produced by the production method of any of the above embodiments.

[0018] A heat-insulating device is characterized by comprising the above-mentioned foam plastic.

[0019] Compared with the existing solutions, the present invention has the following beneficial effects:

[0020] The above-mentioned foam plastic molding equipment and foam plastic molding method are provided with a circulation cavity in the molding mold. When foaming molding is carried out, a circulating high-temperature liquid is introduced into the circulation cavity through a liquid circulation device to quickly heat the molding mold, so that the surface of the plastic particles is quickly plasticized and molded at high temperature. In addition, since the surface of the molding cavity is smooth, the surface of the foam plastic crust can form a mirror-smooth effect.

[0021] At the same time, the surface of the foam plastic products is smooth and seamless, which is stronger than ordinary foam plastics, more effectively avoids the accumulation of dust and the breeding of bacteria, and is more beautiful. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of a partial structure of a foam plastic molding device according to an embodiment;

[0023] Figure 2 for Figure 1 Another partial structural schematic diagram of the foam plastic molding equipment shown. DETAILED DESCRIPTION

[0024] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0025] It should be noted that when an element is referred to as being “disposed on” another element, it may be directly on the other element or there may be an intermediate element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] like Figure 1 As shown, a foam plastic molding device 100 according to an embodiment of the present invention includes a molding die and a liquid circulation device.

[0028] The forming mold has a forming cavity 112 and a flow cavity (not shown in the figure), and the surface of the forming cavity 112 for the foam plastic skin is smooth.

[0029] The liquid circulation device includes a circulation pipe 151, a liquid storage tank 152 connected to the circulation pipe 151, a circulation pump 153, and a heater 154. The liquid storage tank 152 stores liquid and supplies it to the circulation pipe 151. The circulation pump 153, serving as a power source for the liquid flow, circulates the liquid in the circulation pipe 151. The heater 154 heats the liquid in the circulation pipe 151, for example, to a temperature of 180°C to 200°C.

[0030] The circulation pipe 151 is connected to the circulation cavity to form a liquid circulation loop. Through the liquid circulation device, a circulating high-temperature liquid can be introduced into the circulation cavity of the forming mold.

[0031] like Figure 1 As shown, in one example, a control valve 155 is provided on the circulation pipe 151 , and the control valve 155 controls the flow between the molding cavity 112 and the circulation pipe 151 .

[0032] In one example, the liquid tank 152 is provided with a liquid level detector 156 for detecting the liquid level in the liquid tank 152 .

[0033] In one example, the forming mold includes a male mold 120 and a female mold 110 . The male mold 120 and the female mold 110 cooperate with each other to form a forming cavity 112 . The flow cavity is provided in the female mold 110 .

[0034] In one example, the liquid circulation device further includes a controller (not shown) and a temperature sensor 157. The temperature sensor 157 is used to detect the temperature of the liquid in the circulation pipe 151. The controller is electrically connected to the heater 154 and the temperature sensor 157. The controller controls the liquid in the circulation pipe 151 to maintain a set temperature. When the temperature sensor 157 detects that the temperature of the liquid in the circulation pipe 151 exceeds the preset temperature, the controller controls the heater 154 to stop heating, ensuring the safety and stability of the device.

[0035] Furthermore, in one example, the liquid circulation device further includes a pressure sensor 158 for detecting the hydraulic pressure in the circulation pipe 151 .

[0036] In one example, the male mold 120 is made of a permeable metal and the surface of the mold for the foam skin is smooth.

[0037] In this embodiment, the punch 120 is made of a breathable metal. No air holes or other features are added to the mold surface during the mold manufacturing process. The breathable metal itself is naturally permeable, so air suffocation does not occur during the foam molding process. Therefore, air holes or other features are not required within the punch 120. The foam can be heated and cured effectively during the heat molding process even without air holes or other features. After molding, the contact surface between the foam and the punch 120 is smooth.

[0038] Furthermore, the surface of the convex mold 120 made of breathable metal for forming the foam plastic skin is polished to achieve a mirror effect on the surface of the breathable metal, thereby achieving a plasticized and smooth effect on the surface of the molded foam plastic.

[0039] In one example, the permeable metal used to make the male mold 120 can be, but is not limited to, a microporous ternary alloy. More specifically, an electroformed microporous ternary alloy can be used.

[0040] The permeable metal itself has numerous pores, allowing gas to escape between the plastic particles and between the plastic particles and the punch 120. In one example, the pores of the permeable metal used to make the punch 120 range from 10 μm to 1000 μm. Furthermore, in another example, the pores of the permeable metal used to make the punch 120 range from 100 μm to 500 μm, ensuring that all gas can escape. This prevents the foam product from becoming trapped due to the inability to escape gas, thus maintaining a smooth surface.

[0041] In one example, the material of the die 110 is aluminum or aluminum alloy, preferably high thermal conductivity aluminum, which is conducive to the high-temperature liquid quickly transferring heat to the die 110, increasing the speed of plasticization of the foam plastic surface, thereby improving the smoothness of the foam plastic surface.

[0042] In one example, the roughness of the surface of the female mold 110 for forming the foam skin is Ra0.6 to Ra0.8.

[0043] In one example, the foam plastic molding apparatus 100 further includes an exhaust device connected to the molding cavity 112, and the air pressure in the molding cavity 112 is controlled by the exhaust device connected to the molding cavity 112. An exhaust valve 113 is provided on the pipe connecting the exhaust device and the molding cavity 112. In one example, the foam plastic molding apparatus 100 further includes a drainage device connected to the molding cavity 112, and moisture in the molding cavity 112 is drained by the drainage device connected to the molding cavity 112. A drainage valve 114 is provided on the pipe connecting the drainage device and the molding cavity 112. This ensures that there is no air or moisture between the particles, thereby effectively combining them, preventing the formation of material gaps between the particles, and promoting the smoothness of the product surface.

[0044] In one example, a steam device is also included, which is connected to the molding chamber 112. Furthermore, the steam outlet of the molding chamber 112 is located on at least two sidewalls of the molding chamber 112. A steam control valve 115 is provided on the pipe connecting the steam device and the molding chamber 112. When molding begins, the steam device can input steam into the molding chamber 112 to provide a heat source.

[0045] In one example, the foam molding apparatus 100 further includes a spray device, the water outlet of which is in communication with the molding cavity 112. After molding is completed, the spray device sprays cooling water into the molding cavity 112 to accelerate the reduction of the product temperature. Furthermore, in one example, there are multiple spray devices, which are arranged around the molding cavity 112.

[0046] like Figure 2 As shown, in one example, the foam molding apparatus 100 further includes a material tank 130 and a feed mechanism. More specifically, the material tank 130 is equipped with a feed valve 131 and a pressure-maintaining valve 132. The feed mechanism includes a feed pipe 141, a material gun 142, and a pressurizing component 143. One end of the feed pipe 141 is connected to the discharge port of the material tank 130, and the other end is connected to the material gun 142. The material gun 142 is connected to the molding cavity 112. The pressurizing component 143 is positioned near the discharge port of the material tank 130 and is connected to the feed pipe 141 to ensure smooth passage of the raw material. In one example, the feed mechanism further includes a material gun wind control component 144, which is connected to the material gun 142 to control the spraying speed of the material gun 142.

[0047] Furthermore, the present invention also provides a method for producing foam plastics, using any of the foam plastic molding devices 100 described above, the method comprising the following steps:

[0048] Adding the raw materials of the foam plastic into the molding cavity 112;

[0049] Steam is introduced into the molding cavity 112 to pressurize and heat it, and a high-temperature liquid is circulated in the circulation cavity through a liquid circulation device to further heat the molding die, so that the raw material of the foam plastic is foamed and formed. The temperature of the high-temperature liquid is 180°C to 200°C.

[0050] Cool and demould.

[0051] The above-mentioned foam plastic molding equipment 100 and method are provided with a circulation cavity in the molding mold. When foaming molding is performed, a circulating high-temperature liquid is introduced into the circulation cavity through a liquid circulation device to quickly heat the molding mold, so that the surface of the plastic particles is quickly plasticized and molded at high temperature. In addition, since the surface of the molding cavity 112 is smooth, the surface of the foam plastic crust can form a mirror-smooth effect.

[0052] At the same time, the surface of the foam plastic products is smooth and seamless, which is stronger than ordinary foam plastics, more effectively avoids the accumulation of dust and the breeding of bacteria, and is more beautiful.

[0053] The outer surface of the foam plastic insulation box has a smooth mirror effect, and the logo can be directly pasted without the need for secondary processing cloth bags, which saves costs, is easy to operate, and is more beautiful.

[0054] In one example, the heating time is 15s to 20s.

[0055] In one example, during the foaming process, the air pressure in the molding cavity 112 is controlled to be 10 kg / cm. 2 ~14kg / cm 2 .

[0056] The high-temperature liquid preferably has a high thermal conductivity to quickly transfer heat for heating. In one example, the thermal conductivity of the high-temperature liquid is 0.3 W / mK to 0.6 W / mK. Furthermore, in one example, the thermal conductivity of the high-temperature liquid is 0.5 W / mK to 0.6 W / mK.

[0057] During the foam plastic molding process, the air pressure in the molding cavity 112 is controlled by an air extraction device connected to the molding cavity 112, and the moisture in the molding cavity 112 is drained by a drainage device connected to the molding cavity 112. This ensures that there is no air or moisture between the particles, thereby effectively combining the particles, preventing the formation of material gaps between the particles, and promoting the smoothness of the product surface.

[0058] During the molding process, while water cooling is in progress, an exhaust device simultaneously extracts air. Because the permeable metal punch 120 has numerous apertures, convection airflow within the molding cavity 112 rapidly dissipates the heat generated by the steam generated by the water cooling within the cavity. Specifically, during cooling, water cooling is employed: cold water at approximately 20°C is sprayed onto the product, which is approximately 100°C, generating steam. This steam is then extracted by an exhaust device, and the apertures of the punch 120 cooperate with the vacuum airflow to extract the generated steam. This improves cooling efficiency and shortens the cooling time.

[0059] Products produced using ordinary molds use metal conduction cooling during water cooling, which takes a long time to cool down and often results in a large number of defective products due to poor cooling. The manufacturing method of the above embodiment can avoid this problem.

[0060] Similarly, during the heating process, the permeability of the punch 120 is utilized, and the exhaust device accelerates the convection in the molding cavity 112, which can also improve the heating efficiency and achieve energy-saving and efficient production.

[0061] In the molding process, after the raw materials are added, steam is used to pressurize and expand the plastic particles, and at the same time, the exhaust device is opened to extract the air between the particles.

[0062] The method for producing the foam plastic of the present invention can be used for, but not limited to, the molding of expanded polypropylene (EPP).

[0063] At the same time, the surface of the foam plastic products is smooth and seamless, which is stronger than ordinary foam plastics, more effectively avoids the accumulation of dust and the breeding of bacteria, and is more beautiful.

[0064] Furthermore, the present invention also provides a foam plastic, which is produced by the production method of any of the above embodiments.

[0065] Furthermore, the present invention also provides a heat-insulating device comprising the above-mentioned foam plastic.

[0066] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A foam plastic molding device, characterized in that: The invention comprises a forming mold and a liquid circulation device, wherein the forming mold has a forming cavity and a circulation cavity, the surface of the forming cavity for foam plastic skinning is smooth, and the liquid circulation device comprises a circulation pipe and a liquid storage tank, a circulation pump and a heater connected to the circulation pipe, and the circulation pipe is connected to the circulation cavity to form a liquid circulation loop. The forming mold includes a male mold and a female mold, the male mold and the female mold cooperate with each other to form the forming cavity, and the flow cavity is provided in the female mold; The male mold is made of air-permeable metal, and the surface of the male mold used for the foam plastic crust is smooth; The material of the die includes aluminum or aluminum alloy; The foam plastic molding equipment further includes an air extraction device connected to the molding cavity, and the air pressure in the molding cavity is controlled by the air extraction device connected to the molding cavity; The foam plastic molding equipment further includes a drainage device connected to the molding cavity, and the moisture in the molding cavity is discharged through the drainage device connected to the molding cavity; The foam plastic molding apparatus further comprises a steam device, wherein the steam device is in communication with the molding cavity; The foam plastic molding equipment further comprises a spray device, wherein a water spray port of the spray device is in communication with the molding cavity; The pore diameter of the air permeable metal is 10 μm to 1000 μm; The surface roughness of the concave mold used for foam plastic crusting is Ra0.6 to Ra0.8; During the molding process, when water cooling is performed, since the male mold has countless apertures, the exhaust device can form air convection in the molding cavity when exhausting air, and quickly discharge the steam heat generated by the water cooling in the mold cavity; during the heating process, the exhaust device utilizes the air permeability of the male mold to accelerate the convection in the molding cavity, thereby improving the heating efficiency.

2. The foam plastic molding equipment according to claim 1, characterized in that The permeable metal includes a microporous ternary alloy.

3. The foam plastic molding equipment according to claim 1 or 2, characterized in that It also includes a material tank and a feeding mechanism, the feeding mechanism includes a feeding pipe, a material gun and a boosting component, one end of the feeding pipe is connected to the discharge port of the material tank, the other end of the feeding pipe is connected to the material gun, the material gun is connected to the molding chamber, and the boosting component is arranged near the discharge port of the material tank and is connected to the feeding pipe.

4. A method for producing foam plastics, characterized in that: Using the foam plastic molding equipment according to any one of claims 1 to 3, the manufacturing method comprises the following steps: adding raw materials of foam plastic into the molding cavity; Steam is introduced into the molding cavity to pressurize and heat it, and a high-temperature liquid is circulated in the circulation cavity through the liquid circulation device to further heat the molding die, so that the raw material of the foam plastic is foamed and molded, wherein the temperature of the high-temperature liquid is 180° C. to 200° C.; Cool and demould.

5. The method for producing foam plastics according to claim 4, wherein: During the foaming process, the air pressure in the molding cavity is controlled to be 10kg / ㎝²~14kg / ㎝².

6. The method for producing foam plastics according to claim 4 or 5, wherein: The thermal conductivity of the high-temperature liquid is 0.3W / mK to 0.6W / mK.

7. A foam plastic, characterized in that: The method is as described in any one of claims 4 to 6.

8. A heat preservation device, characterized in that: The invention provides a foamed plastic according to claim 7.

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