Heating element of continuous hot press molding device

Abstract

The invention relates to a heating element of a continuous hot press molding device, which mainly comprises a resistor, the outer surface of the resistor is coated with an insulated airtight protective layer, and the two ends of the resistor are exposed out of the two ends of the protective layer and form wiring ends; the continuous hot press molding device is provided with an airtight cavity, an insulating layer is arranged at the position, corresponding to the penetrating position of the airtight cavity, of the resistor, and the resistor is connected with the airtight cavity through the insulating layer. The resistance body may be made of silicon carbide, the protective layer may be made of high-purity aluminum oxide or silicon carbide, and the insulating layer may be made of a ceramic insulating material. The contact part of the heating element and the airtight cavity of the continuous hot-press forming device is not affected by high-temperature oxidation, damage and the like, and the heating element is particularly suitable for the high-temperature airtight type continuous hot-press forming device.

Description

Technical Field

[0001] The invention belongs to the technical field of heaters, in particular to a heating element suitable for an airtight continuous hot pressing forming device. Background Art

[0002] Today, thermoforming is a method for processing polymer materials. It involves placing a material of a certain thickness in a mold, heating the mold or the environment to soften the material and coat the mold surface. The material is then squeezed by a machine and solidified after a cooling stage to obtain a thermoformed product.

[0003] Taking glass as an example of a material that can be thermoformed, due to its high light transmittance, it is often chosen as the outer shell of the window portion of display devices (such as mobile phones, watches, and other electronic products). As you can see, handheld electronic products often have a glass shell on the surface to protect the display module inside. Currently, most glass shells have a flat surface, resulting in a seam on the top surface of the electronic product. Furthermore, since a certain width of mechanical portion must be retained around the perimeter of the electronic product to hold the flat glass, the top surface of the electronic product cannot be fully utilized. Therefore, three-dimensional or curved glass has gradually been used in the glass shells of electronic products.

[0004] Flat glass housings are relatively easy to manufacture, while glass housings with three-dimensional shapes are more challenging. Currently, there are two common methods for manufacturing three-dimensional glass housings. The first involves fabricating multiple flat glass units and then gluing their edges together to form a three-dimensional glass housing. The second involves manufacturing a rectangular glass block of a certain thickness and then repeatedly grinding it to create a multi-sided three-dimensional shape. However, both methods are time-consuming and labor-intensive, resulting in very slow production rates. Generally speaking, since glass material is flat, the preferred method for producing shaped glass is to place the flat glass material between an upper mold and a lower mold. The upper and lower molds, along with the glass material, are then heated to soften the glass material. Once the glass material has softened, the upper and lower molds can be closed, allowing the upper mold to work with the lower mold along a closing direction to shape the glass material's shape, thereby producing the corresponding molded glass.

[0005] The prior art discloses an "airtight molded three-dimensional glass continuous forming device", which is a new design of a continuous forming device designed for molded three-dimensional glass products. It is mainly composed of a furnace body, which is a closed type. Exchange systems are provided at both ends of the exterior of the furnace body, and an airtight cavity is provided inside the furnace body; the exchange system is provided at both ends of the furnace body, and an external conveying channel is provided between the exchange systems at both ends of the furnace body. Each exchange system includes an inner airtight door provided on the side of the furnace body and an outer airtight door provided on the side of the external conveying channel. An airtight space is formed between the inner airtight door and the outer airtight door, and a displacement device is provided to push the carrier into or out of the furnace body; the airtight cavity is provided inside the furnace body, including an airtight cavity, and an inner conveying channel is provided in the airtight cavity. The inner conveying channel connects the inner airtight doors of the exchange systems at both ends of the furnace body, and is provided with a slide rail to serve as a track for the movement of the carrier. The airtight cavity is airtight, and protective gas is introduced, and according to the working The process area is divided into a heating zone), a high-temperature forming zone and a cooling zone. The heating zone and the high-temperature forming zone are provided with at least one thermal insulation layer, and a heat field is formed in the center of the thermal insulation layer. The heat field is provided with a heating element of a temperature required by the process procedure. The cooling zone has a cooling device, and the high-pressure forming zone is provided with a pressurizing system; an external conveying channel connects the exchange system at both ends of the furnace body; the pressurizing system is mainly composed of a pressure cylinder, a pressurizing shaft and a pressurizing column; the present invention is constructed in this way, the flat glass to be formed is placed on the forming surface of the mold, and the mold is placed on the carrier, and the carrier enters the airtight cavity through the exchange system, and is preheated in the heating zone and the high temperature in the high-temperature forming zone, so that the glass in the mold is softened and formed by the pressurization of the pressurizing system, and then cooled in the cooling zone, sent out of the furnace body through the exchange system, and then demolded, which can indeed achieve the effect of continuous, high-efficiency and high-quality molding of three-dimensional glass.

[0006] Furthermore, for existing heating elements please refer to Figure 1As shown, the heater primarily comprises an electric heating element A and a protective tube B (typically a quartz tube) surrounding the outer edge of the heating element A. The heating element A is exposed at the two open ends of the protective tube B, forming terminal D. The open ends of the protective tube B are secured to the entire structure with fixings C. This type of conventional heater is widely used in household appliances and other heating machinery. However, when this heater is used in an airtight continuous molding device for three-dimensional glass, the lack of an airtight seal on both sides of the protective tube allows ambient gases (such as nitrogen, hydrogen, argon, and chlorine, some of which are corrosive) to penetrate through the sides of the protective tube and enter the interior. This can corrode and damage the heating element within the protective tube, or even lead to its failure. Furthermore, as the softening temperature of glass continues to rise (especially for aluminum-containing glass), the hot-pressing of materials other than glass, such as metals, ceramics, or metal-ceramic heterogeneous composites, requires even higher temperatures within the airtight cavity. Existing quartz protective tubes for heating elements cannot meet these high-temperature requirements. Furthermore, the heating elements within the hot-pressing cavity of existing continuous hot-pressing apparatuses are placed in direct contact with the hot-pressing cavity, which can easily lead to adverse effects such as oxidation and damage at the contact point between the heating element and the airtight cavity. Summary of the Invention

[0007] The object of the present invention is to provide a heating element suitable for a high-temperature airtight continuous hot pressing forming device.

[0008] The heating element of the continuous hot pressing forming device of the present invention mainly includes an impedance body, the outer surface of which is covered with an insulating and airtight protective layer. The two ends of the impedance body are exposed at the two ends of the protective layer and form wiring terminals; the continuous hot pressing forming device has an airtight cavity, and the impedance body is provided with an insulating layer at a relative position where it passes through the airtight cavity, and is connected to the airtight cavity through the insulating layer.

[0009] The resistor of the present invention is made of silicon carbide.

[0010] The protective layer of the present invention is made of an inorganic insulating material, such as high-purity aluminum oxide or silicon carbide.

[0011] The insulating layer of the present invention is made of ceramic insulating material.

[0012] In addition to protecting the resistor from corrosion or adverse reactions, the present invention also has the effect of preventing the contact between the heating element and the airtight cavity of the continuous hot pressing molding device from adverse effects such as high-temperature oxidation and damage. It is particularly suitable for high-temperature airtight continuous hot pressing molding devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a plan view of the existing heating element installation;

[0014] Figure 2 This is a front cross-sectional view of the airtight continuous hot pressing molding device of the present invention;

[0015] Figure 3 This is a cross-sectional view of the upper end of the airtight continuous hot pressing molding device of the present invention;

[0016] Figure 4 This is a cross-sectional view of the temperature rising zone of the airtight continuous hot pressing forming device of the present invention;

[0017] Figure 5 This is a cross-sectional view of the high-temperature forming area of ​​the airtight continuous hot pressing forming device of the present invention;

[0018] Figure 6 This is a cross-sectional view of a heating element according to an embodiment of the present invention.

[0019] In the picture:

[0020] 1: furnace body; 2: exchange system; 20: inner airtight door; 21: outer airtight door; 22: airtight space; 23: displacement device; 3: airtight cavity; 30: airtight cavity; 300: air layer; 31: inner conveying channel; 32: heating zone; 33: high-temperature forming zone; 34: cooling zone; 35: thermal insulation layer; 350: lower pressure plate; 351: reflective plate; 36: thermal field; 38: cooling device; 39: slide rail; 4: outer conveying channel; 5: pressurizing system; 50: pressure cylinder; 51: pressurizing shaft; 52: pressurizing column; 53: cooling device; 6: carrier plate; 7: mold; 8: support device; 80: support column; 81: lifting device; 9: heating element; 90: impedance body; 91: protective layer; 92: terminal; 93: insulation layer. DETAILED DESCRIPTION

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0022] The present invention is particularly directed to a novel design of heating elements for an airtight continuous atmosphere sintering molding device for hot press molding products. The hot press molding materials of the present invention include but are not limited to glass, metal, ceramic, or metal-ceramic heterogeneous composite materials. The airtight continuous hot press molding device used in the present invention can be found in Figure 2 、 Figure 3 As shown, it mainly includes:

[0023] The furnace body 1 is a closed type, with an exchange system 2 provided at both ends of the exterior of the furnace body 1 and an airtight cavity 3 provided inside the furnace body 1;

[0024] The exchange systems 2 are provided at both ends of the furnace body 1. An external conveying channel 4 is provided between the exchange systems 2 at both ends of the furnace body 1. Each exchange system 2 includes an inner airtight door 20 provided on one side of the furnace body 1 and an outer airtight door 21 provided on the side of the external conveying channel 4. An airtight space 22 is formed between the inner airtight door 20 and the outer airtight door 21. A displacement device 23 is provided to push the carrier plate 6 into or out of the furnace body 1.

[0025] The airtight chamber 3 is provided inside the furnace body 1 and includes an airtight chamber 30. The airtight chamber 30 has an inner conveying channel 31. The inner conveying channel 31 connects the airtight doors 20 of the exchange system 2 at both ends of the furnace body 1 and is provided with a slide rail 39 (see Figure 4 and Figure 5 ), as a track for the movement of the carrier 6, the airtight chamber 3 is airtight, and a protective gas is introduced (generally an inert gas, such as nitrogen, hydrogen, argon, etc.; the device for providing the protective gas is a prior art and will not be elaborated on), and is divided into a heating zone 32, a high-temperature forming zone 33 and a cooling zone 34 according to the process area, the heating zone 32 and the high-temperature forming zone 33 are provided with at least one thermal insulation layer 35, and a thermal field 36 is formed in the center of the thermal insulation layer 35, and a heating element 9 of a temperature required by the process procedure is provided in the thermal field 36 (the temperature control device and the like are prior art and will not be elaborated on), the cooling zone 34 has a cooling device 38 (the cooling device (38) is a prior art and will not be elaborated on), and the high-pressure forming zone 33 is provided with a pressurizing system 5;

[0026] The external conveyor 4 connects the exchange system 2 at both ends of the furnace body 1;

[0027] Pressurized system 5, see Figure 4 As shown, the pressurizing system 5 is mainly composed of a pressurizing cylinder 50, a pressurizing shaft 51 and a pressurizing column 52;

[0028] In the present invention thus constructed, the object to be hot-pressed is placed on the molding surface of the mold 7, and the mold 7 is placed on the carrier 6. The carrier 6 enters the airtight chamber 3 through the exchange system 2, and is preheated in the temperature rising zone 32 (to avoid damage due to too rapid temperature changes) and the high temperature of the high-temperature molding zone 33, so that the object to be hot-pressed in the mold is softened, and is formed by the pressurization of the pressurization system 5. After cooling in the cooling zone 34, it is sent to the outside of the furnace body 1 through the exchange system 2 and then demolded.

[0029] See also Figure 3As shown, the present invention is provided with an exchange system 2 on both sides of the furnace body 1, each exchange system 2 includes an inner airtight door 20 provided on one side of the furnace body 1 and an outer airtight door 21 provided on the side of the outer conveying channel 4, and an airtight space 22 is formed between the inner airtight door 20 and the outer airtight door 21. Before the carrier 6 is fed into the furnace body 1, the inner airtight door 20 and the outer airtight door 21 at the head end of the furnace body 1 are closed. After the airtight space 22 is evacuated and the protective gas is introduced to the same environment as that in the airtight cavity 3 (the vacuuming process will remove the air on the mold 7 (especially The inner airtight door 20 on the furnace body side is opened to push the carrier plate 6 into the airtight chamber 3. Before the carrier plate 6 is sent out of the airtight chamber 3, the inner airtight door 20 and the outer airtight door 21 at the rear end of the furnace body are closed, and the airtight space 22 has been evacuated and the protective gas is introduced to the same environment as that in the airtight chamber 3. The inner airtight door 20 on the furnace body side is opened to push the carrier plate 6 into the airtight space 22. This prevents the airtight chamber 3 from mixing with the air outside the furnace, thereby improving the molding quality of the object to be hot-pressed.

[0030] See also Figure 6 As shown, the heating element 9 of the present invention mainly includes an impedance body 90 and a protective layer 91 covering the outer edge of the impedance body 90 to form an insulating and airtight layer. The two ends of the impedance body 90 are exposed at the two ends of the protective layer 91 and form terminal 92. The impedance body 90 is provided with an insulating layer 93 at a position relative to the airtight cavity 30 of the continuous hot pressing molding device (see FIG. Figure 4 、 Figure 5 ) The insulating layer 93 is connected to the airtight cavity 30. Since the protective layer 91 and the resistor 90 are insulated and airtight, the gases in the ambient environment cannot penetrate into the protective layer 91. This will not cause the resistor 90 in the protective layer 91 to be corroded or damaged, or to be affected by any adverse reactions. Furthermore, since the resistor 90 is provided with an insulating layer 93 at a position relative to the airtight cavity 30 of the continuous hot pressing molding device, the insulating layer 93 is connected to the airtight cavity 30. That is, the heating element and the airtight cavity 30 are connected by the insulating layer 93, rather than being directly in contact. This will prevent the contact portion between the heating element 9 and the airtight cavity 30 from being oxidized or damaged due to high temperature, and is particularly suitable for high-temperature airtight continuous hot pressing molding devices.

[0031] The resistor 90 of the present invention is made of silicon carbide.

[0032] The protective layer 91 of the present invention is made of an inorganic insulating material, such as high-purity aluminum oxide or silicon carbide, so as to be suitable for a high-temperature airtight continuous hot pressing device.

[0033] The protective layer 91 of the present invention is coated on the outer edge of the resistor 90 in a coating manner.

[0034] The insulating layer 93 of the present invention is made of ceramic insulating material.

[0035] The above embodiments are merely preferred embodiments for the purpose of fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are within the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

Claims

1. A heating element for a continuous hot pressing forming device, characterized in that: include: An impedance body, the outer surface of which is covered with an insulating and airtight protective layer, with two ends of the impedance body exposed at two ends of the protective layer and forming connection terminals; The continuous hot pressing forming device has an airtight cavity. The impedance body is provided with an insulating layer at a position corresponding to the position where the impedance body passes through the airtight cavity, and is connected to the airtight cavity through the insulating layer.

2. The heating element of the continuous hot pressing forming device according to claim 1, characterized in that The resistor is made of silicon carbide.

3. The heating element of the continuous hot pressing forming device according to claim 1, characterized in that The protective layer is made of high-purity aluminum oxide.

4. The heating element of the continuous hot pressing forming device according to claim 1, characterized in that The protective layer is composed of silicon carbide.

5. The heating element of the continuous hot pressing forming device according to claim 1, characterized in that: The insulating layer is made of ceramic insulating material.

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