Drying device for producing a coated kraft paper

Abstract

The utility model relates to paper processing technical field especially relates to a kind of drying device for production of coated kraft paper, including frame and drying cabinet, drying cabinet is fixedly installed in the upper end of frame, the inside of frame is provided with first conveyor belt, the side of frame is fixedly installed with first motor, the surface of first conveyor belt is provided with several array arrangement's through-hole, the inside of first conveyor belt is provided with negative pressure tank, the side of frame is fixedly installed with air duct, air duct is through with negative pressure tank, the upper end of air duct is provided with hot blast machine, and the output of hot blast machine is provided with air supply mechanism;The utility model is dried by hot blast machine cooperation air supply mechanism to the drying cabinet inside conveying hot air blowing paper web and carries out drying operation, while hot blast machine runs and continuously generates negative pressure in negative pressure tank by air duct intercommunication, and the even adsorption of upper coated paper is formed by the through-hole on the surface of first conveyor belt, can be applied to paper web Perpendicular downward constraint force, offset curling tendency due to thermal shrinkage and thermoplastic deformation.

Description

Technical Field

[0001] This utility model relates to the field of paper processing technology, and in particular to a drying device for producing coated kraft paper. Background Technology

[0002] Laminated kraft paper is a composite material made by laminating a layer of polyethylene, polypropylene, or biodegradable polylactic acid plastic film onto a high-strength kraft paper substrate through a hot melt extrusion coating process. This greatly improves the moisture-proof, oil-proof, sealing, and heat-sealing properties of kraft paper, making it widely used in food packaging, electronic product packaging, shopping bags, and various industrial packaging fields. After lamination, drying is required to ensure that the plastic film is firmly bonded to the paper base and forms a smooth and flat surface. This is a key process to ensure the quality of the finished product.

[0003] Currently, the drying equipment commonly used in the industry is the hot air circulating oven. Its basic working principle is to deliver hot air into the oven through a hot air blower and blow the hot air onto the surface of the coated paper conveyed by the conveyor belt. The moisture is evaporated and the film is cured through convection heat transfer. However, kraft paper itself will generate shrinkage stress during the process of heating and water loss, and the plastic film exhibits thermoplasticity at high temperatures. The combined effect of the two causes the paper web to be very easy to curl during the drying process, which affects the quality of the finished paper.

[0004] Therefore, to address the aforementioned issues, a drying device for producing coated kraft paper can be designed. This device transports the kraft paper inside the drying oven via a conveyor belt with perforated surfaces. Inside the conveyor belt is a negative pressure box connected to the air inlet of a hot air blower. During hot air blower operation, a continuous and stable negative pressure environment is generated inside the negative pressure box. This creates a uniform adsorption force on the coated paper above through the perforations on the conveyor belt surface. This not only effectively improves the stability of the paper web transport but also counteracts the curling tendency caused by thermal shrinkage and thermoplastic deformation by applying a vertically downward constraint force to the paper web, ensuring the flatness and quality stability of the finished paper. Utility Model Content

[0005] To overcome the problem that during the drying process, kraft paper itself will generate shrinkage stress during heating and water loss, and plastic film will exhibit thermoplasticity at high temperatures. The combined effect of these two factors makes the paper web very prone to curling during the drying process, which affects the quality of the finished paper.

[0006] The technical solution of this utility model is as follows: a drying device for producing coated kraft paper, including a base frame, a machine frame, and a drying box. The machine frame is fixedly installed on the upper end of the base frame, and the drying box is fixedly installed on the upper end of the machine frame. It also includes a first conveyor belt disposed inside the machine frame. A first motor is fixedly installed on one side of the machine frame. A plurality of arrayed through holes are opened on the surface of the first conveyor belt. A negative pressure box is disposed inside the first conveyor belt. An air duct is fixedly installed on one side of the machine frame. The air duct is connected to the negative pressure box. A hot air fan is disposed at the upper end of the air duct. The input end of the hot air fan is connected to the air duct. An air supply mechanism is disposed at the output end of the hot air fan. A set of conveying mechanisms is disposed on both sides of the first conveyor belt, and a set of buffer mechanisms is disposed on both sides of the drying box.

[0007] Preferably, the first conveyor belt is driven by the first motor to transport the paper web. The conveying mechanism can transport or output the paper web via the first conveyor belt. During operation, the hot air blower is started, and the air supply mechanism blows hot air into the drying chamber to dry the paper web. At the same time, negative pressure is continuously generated in the negative pressure chamber through the through-holes on the surface of the first conveyor belt to form a uniform adsorption force on the coated paper above. This not only effectively improves the stability of the paper web transport, but also counteracts the curling tendency caused by thermal shrinkage and thermoplastic deformation by applying a vertically downward constraint force to the paper web, ensuring the flatness and quality stability of the finished paper. The paper web passes through a buffer mechanism when entering and leaving the drying chamber, which can effectively alleviate the temperature shock caused by the sudden exposure of the paper web to an excessively cold or hot environment, and avoid physical damage to the coated layer caused by sudden temperature changes.

[0008] Preferably, the air supply mechanism includes an insulated pipe and a diffuser. The diffuser is fixedly installed inside the drying oven, and the insulated pipe runs through and connects the hot air blower and the diffuser to form a directional hot air delivery channel.

[0009] Preferably, the conveying mechanism includes a second conveyor belt, a second motor, and a transmission component. The second conveyor belt is disposed inside the frame, the second motor is fixedly installed at the lower end of the frame, and a transmission component is provided between the second motor and the second conveyor belt to establish a driving connection.

[0010] Preferably, the buffer mechanism includes a mounting box and a heating plate. The mounting box is fixedly installed on the upper end of the frame and is connected to the drying box. The heating plate is fixedly installed on the lower end of the top surface of the inner cavity of the mounting box.

[0011] Preferably, the output temperature of the electric heating plate is lower than the output temperature of the hot air from the hot air blower.

[0012] Preferably, a guide frame is fixedly mounted at one end of the frame by fasteners, and the guide frame is located at the input end of a set of second conveyor belts (701).

[0013] Preferably, an electrical control box is fixedly installed inside the base frame.

[0014] The beneficial effects of this utility model are:

[0015] 1. During operation, the hot air blower is started, and the hot air conveying mechanism blows hot air into the drying box to dry the paper web. At the same time, negative pressure is continuously generated in the negative pressure box through the through-hole of the first conveyor belt, which forms a uniform adsorption force on the coated paper above. This not only effectively improves the stability of paper web conveying, but also counteracts the curling tendency caused by heat shrinkage and thermoplastic deformation by applying a vertically downward constraint force to the paper web, ensuring the flatness and quality stability of the finished paper.

[0016] 2. When the paper web enters or exits the drying chamber, it passes through a set of mounting boxes. The electric heating plates inside the mounting boxes can maintain the temperature of the drying chamber and the drying chamber. This not only ensures the drying quality, but also effectively mitigates the temperature shock caused by the sudden exposure of the paper web to excessively cold or hot environments. It also avoids physical damage to the coating layer of the paper web caused by sudden temperature changes, thereby further improving the yield and quality reliability of the product. Attached Figure Description

[0017] Figure 1 The diagram shown is a first three-dimensional structural schematic of the drying device for producing coated kraft paper according to this utility model.

[0018] Figure 2 The diagram shown is a second three-dimensional structural schematic of the drying device for producing coated kraft paper according to this utility model.

[0019] Figure 3 The diagram shown is a third-dimensional structural schematic of the drying device for producing coated kraft paper according to this utility model.

[0020] Figure 4 The diagram shown is a three-dimensional structural schematic of the pressing component of the drying device for producing coated kraft paper according to this utility model.

[0021] Explanation of reference numerals in the attached drawings: 1. Base frame; 2. Machine frame; 201. Negative pressure box; 202. Guide frame; 3. Drying box; 4. First conveyor belt; 401. Through hole; 402. First motor; 5. Air duct; 6. Hot air blower; 601. Insulation pipe; 602. Diffuser; 701. Second conveyor belt; 702. Second motor; 703. Transmission component; 801. Mounting box; 802. Heating plate; 9. Electrical control box. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] Please see Figure 1 , Figure 3 and Figure 4This utility model provides an embodiment: a drying device for producing coated kraft paper, including a base frame 1, a machine frame 2, and a drying chamber 3. The machine frame 2 is fixedly installed on the upper end of the base frame 1, and the drying chamber 3 is fixedly installed on the upper end of the machine frame 2. It also includes a first conveyor belt 4 disposed inside the machine frame 2. A first motor 402 is fixedly installed on one side of the machine frame 2. The surface of the first conveyor belt 4 has several arrayed through holes 401. A negative pressure box 201 is disposed inside the first conveyor belt 4. An air duct 5 is fixedly installed on one side of the machine frame 2, communicating with the negative pressure box 201. A hot air blower 6 is disposed at the upper end of the air duct 5, with its input end communicating with the air duct 5. An air supply mechanism is disposed at the output end of the hot air blower 6. A set of conveying mechanisms is disposed on both sides of the first conveyor belt 4, and a set of buffer mechanisms is disposed on both sides of the drying chamber 3. The device is powered by the first motor 402. 2 drives the first conveyor belt 4 to operate and transport the paper web. The conveying mechanism can transport or output the paper web on the first conveyor belt 4. During operation, the hot air blower 6 is started and the air supply mechanism delivers hot air to the drying box 3 to dry the paper web. At the same time, the through-flow air duct 5 continuously generates negative pressure in the negative pressure box 201. The through holes 401 on the surface of the first conveyor belt 4 form a uniform adsorption force on the coated paper above. This not only effectively improves the stability of the paper web transport, but also applies a vertically downward constraint force to the paper web to counteract the curling tendency caused by heat shrinkage and thermoplastic deformation, ensuring the flatness and quality stability of the finished paper. The paper web passes through a set of buffer mechanisms when entering and leaving the drying box 3, which can effectively alleviate the temperature shock caused by the sudden exposure of the paper web to an excessively cold or hot environment and avoid physical damage to the coated layer caused by sudden temperature changes.

[0024] Please see Figure 3 and Figure 4 In this embodiment, the air supply mechanism includes an insulation pipe 601 and a diffuser 602. The diffuser 602 is fixedly installed inside the drying chamber 3, and the insulation pipe 601 connects the hot air blower 6 and the diffuser 602 to form a directional hot air delivery channel. The hot air output from the hot air blower 6 is delivered to the diffuser 602 through the insulation pipe 601. The diffuser 602 ensures that the hot air is evenly distributed and effectively blows onto the paper web surface, improving drying efficiency and temperature field uniformity. The buffer mechanism includes a mounting box 8. 01 and heating plate 802, mounting box 801 is fixedly installed on the upper end of frame 2, mounting box 801 is connected to drying box 3, heating plate 802 is fixedly installed on the lower end of the top surface of the inner cavity of mounting box 801; the output temperature of heating plate 802 is lower than the hot air output temperature of hot air blower 6; by heating plate 802, the temperature inside mounting box 801 is increased, forming a temperature buffer zone when paper web enters and exits drying box 3, effectively alleviating stress changes in coating layer caused by sudden changes in ambient temperature, and avoiding physical damage.

[0025] Please see Figure 1 and Figure 2In this embodiment, the conveying mechanism includes a second conveyor belt 701, a second motor 702, and a transmission component 703. The second conveyor belt 701 is disposed inside the frame 2, and the second motor 702 is fixedly installed at the lower end of the frame 2. A transmission component 703 is provided between the second motor 702 and the second conveyor belt 701 to establish a driving connection. A guide frame 202 is fixedly installed at one end of the frame 2 by fasteners. The guide frame 202 is located at the input end of a set of second conveyor belts 701. The guide frame 202 guides and positions the paper web to ensure that it is smoothly conveyed onto the second conveyor belt 701. An electrical control box 9 is fixedly installed inside the base frame 1. The electrical control box 9 serves as the core of electrical control and integrates intelligent control modules such as temperature control, speed adjustment, and negative pressure monitoring to achieve precise control and real-time monitoring of drying process parameters, ensuring the safety and stability of equipment operation.

[0026] During operation, the paper web passes through the inside of the guide frame 202, is conveyed by the second conveyor belt 701, and then transported to the first conveyor belt 4. The paper web is first preheated inside a set of mounting boxes 801 to form a temperature transition zone, reducing the risk of thermal shock caused by direct contact with high-temperature hot air. Then it enters the drying chamber 3, where hot air is delivered to the diffuser 602 through the hot air blower 6 via the heat insulation pipe 601. After passing through the diffuser 602, the hot air is evenly blown onto the surface of the paper web that has passed through the drying chamber 3 for efficient drying.

[0027] When the hot air blower 6 is started, it continuously generates negative pressure in the negative pressure box 201 through the through air duct 5. It acts evenly on the coated paper web through the array of through holes 401 on the surface of the first conveyor belt 4, generating a vertically downward adsorption force. This not only effectively improves the stability of paper web conveying, but also counteracts the curling tendency caused by heat shrinkage and thermoplastic deformation by applying a vertically downward constraint force to the paper web, ensuring the flatness and quality stability of the finished paper.

[0028] After drying, the paper web is pre-cooled by another set of mounting boxes 801. The temperature buffer layer is formed by the gradient cooling function of the electric heating plate 802 to avoid stress changes caused by sudden cooling of the paper web. Finally, it is smoothly output through the second conveyor belt 701 to complete the entire drying production process.

[0029] Through the above steps, the hot air blower 6, in conjunction with the air supply mechanism, delivers hot air into the drying chamber 3 to dry the paper web. Simultaneously, when the hot air blower 6 is running, it continuously generates negative pressure in the negative pressure chamber 201 through the air duct 5. This negative pressure, through the through holes 401 on the surface of the first conveyor belt 4, forms a uniform adsorption force on the coated paper above, which can apply a vertically downward constraint force to the paper web, counteracting the curling tendency caused by thermal shrinkage and thermoplastic deformation. This solves the problem that during the drying process, kraft paper itself will generate shrinkage stress during heating and water loss, while the plastic film exhibits thermoplasticity at high temperatures. The combined effect of these two factors causes the paper web to curl easily during the drying process, affecting the quality of the finished paper.

[0030] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A drying device for producing coated kraft paper, comprising a base frame (1), a machine frame (2), and a drying chamber (3), wherein the machine frame (2) is fixedly installed on the upper end of the base frame (1), and the drying chamber (3) is fixedly installed on the upper end of the machine frame (2), characterized in that: It also includes a first conveyor belt (4) set inside the frame (2), a first motor (402) fixedly installed on one side of the frame (2), a number of arrayed through holes (401) opened on the surface of the first conveyor belt (4), a negative pressure box (201) is set inside the first conveyor belt (4), an air duct (5) is fixedly installed on one side of the frame (2), the air duct (5) is connected to the negative pressure box (201), a hot air blower (6) is set at the upper end of the air duct (5), the input end of the hot air blower (6) is connected to the air duct (5), an air supply mechanism is set at the output end of the hot air blower (6), a set of conveying mechanisms is set on both sides of the first conveyor belt (4), and a set of buffer mechanisms is set on both sides of the drying box (3).

2. The drying apparatus for producing coated kraft paper according to claim 1, characterized in that: The air supply mechanism includes an insulation pipe (601) and a diffuser (602). The diffuser (602) is fixedly installed inside the drying oven (3). The insulation pipe (601) is connected between the hot air blower (6) and the diffuser (602) to form a directional hot air delivery channel.

3. The drying apparatus for producing coated kraft paper according to claim 1, characterized in that: The buffer mechanism includes a mounting box (801) and an electric heating plate (802). The mounting box (801) is fixedly installed on the upper end of the frame (2). The mounting box (801) is connected to the drying box (3). The electric heating plate (802) is fixedly installed on the lower end of the top surface of the inner cavity of the mounting box (801).

4. The drying apparatus for producing coated kraft paper according to claim 3, characterized in that: The output temperature of the electric heating plate (802) is lower than the output temperature of the hot air from the hot air blower (6).

5. A drying apparatus for producing coated kraft paper according to claim 1, characterized in that: The conveying mechanism includes a second conveyor belt (701), a second motor (702), and a transmission component (703). The second conveyor belt (701) is located inside the frame (2), and the second motor (702) is fixedly installed at the lower end of the frame (2). A transmission component (703) is provided between the second motor (702) and the second conveyor belt (701) to establish a driving connection.

6. A drying apparatus for producing coated kraft paper according to claim 5, characterized in that: One end of the frame (2) is fixedly mounted with a guide frame (202) by fasteners, and the guide frame (202) is located at the input end of a set of second conveyor belts (701).

7. A drying apparatus for producing coated kraft paper according to claim 1, characterized in that: An electrical control box (9) is fixedly installed inside the base frame (1).

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