High-efficiency film coating device for food packaging bag production

Abstract

The utility model relates to the field of high -efficient membrane installation of food packaging bag production, especially a kind of high -efficient membrane device of food packaging bag production, including cylinder and apron, sealing ring, setting down cooling mechanism for the quick cooling of packaging bag on it in cylinder, cooling mechanism includes the cooling cavity for cooling cylinder and the reflux cavity for recycling heating hot water, water delivery hole for conveying cold water and water outlet hole for extracting reflux water are provided on apron, centrifugal mechanism that prevents sealing ring from falling off when cylinder high -speed rotation is provided on water delivery hole and water outlet hole.The utility model cooling cavity and reflux cavity adopt reverse spiral design, and are connected with 180 ° U-shaped cavity, constitute a complete counterflow heat exchange system, so that the water inlet with lower temperature and the return water with higher temperature are always in adjacent flow channel, flow reversely, continuously carry out heat exchange, so that the overall heat exchange efficiency reaches maximization.

Description

Technical Field

[0001] This utility model relates to the field of high-efficiency coating packaging in the production of food packaging bags, and in particular to a high-efficiency coating device for the production of food packaging bags. Background Technology

[0002] In the production of food packaging bags, lamination is a key process that involves coating the surface of the packaging bag with molten plastic material (such as PE) to enhance its sealing, moisture resistance, and mechanical strength.

[0003] Existing high-efficiency coating equipment for food packaging bags, such as the one disclosed in CN212528894U, uses a bonding component to limit and clean the packaging bag before coating, and a cooling assembly consisting of a fan and coolant for subsequent cooling. However, it still has many limitations: the cooling method of this device relies only on surface convection and simple liquid cooling, resulting in low heat exchange efficiency and slow cooling speed, making it difficult to meet the needs of high-speed continuous production. Especially when processing large-area or thick film layers, uneven cooling can easily lead to deformation of the coating layer or a decrease in adhesion, affecting product quality. Utility Model Content

[0004] The purpose of this invention is to solve the problems of low efficiency and slow cooling speed in the prior art, and to propose a high-efficiency coating device for the production of food packaging bags.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A high-efficiency coating device for producing food packaging bags includes a roller, a cover plate, and a sealing ring. The roller is equipped with a cooling mechanism for rapidly cooling the packaging bags on it. The cooling mechanism includes a cooling chamber for cooling the roller and a return chamber for recovering heated hot water. The cover plate is equipped with a water inlet for conveying cold water and a water outlet for extracting return water. Both the water inlet and the water outlet are equipped with centrifugal mechanisms to prevent the sealing ring from falling off when the roller rotates at high speed.

[0006] Preferably, the cover plate is fixedly installed on both sides of the drum, and four of them are provided. The cooling mechanism is provided in two sets on the upper and lower sides of the drum.

[0007] Preferably, the cooling mechanism includes a threaded cavity formed inside the drum for meshing and connecting the outer wall of the cooling cavity with the outer wall of the reflux cavity. Both the cooling cavity and the reflux cavity are spiral channels, and the cooling cavity and the reflux cavity are spirals in opposite directions.

[0008] Preferably, a U-shaped cavity is formed at the end of the cooling cavity and the end of the reflux cavity, a water pump is fixedly installed between the end of the cooling cavity and the U-shaped cavity, and a water pipe is fixedly installed between the reflux cavity and the U-shaped cavity.

[0009] Preferably, both the cooling chamber and the reflux chamber are fixedly equipped with guide fins for periodically disturbing the water flow and changing it from laminar flow to turbulent flow. The guide fins cause the cold water at the center to continuously impact the inner walls of the hot cooling chamber and the reflux chamber.

[0010] Preferably, the guide fins are semi-elliptical with a smooth leading edge and a sharp trailing edge. The guide fins are arranged in a crisscross pattern, and the ratio of the flow length of the guide fins to their spacing is controlled between : and :. A pressurizing cavity for increasing the water flow velocity is provided in the middle of the guide fins, and the pressurizing cavity is a pressurizing structure with a large opening and a small outlet.

[0011] Preferably, the centrifugal mechanism includes a circular sleeve fixedly installed at the water inlet and outlet for fixing the sealing ring. The sealing ring has four rectangular cavities circumferentially open, and a weight block is slidably fitted on the rectangular cavity to prevent the sealing ring from falling off during high-speed rotation.

[0012] Compared with the prior art, the present invention has the following advantages: 1. This utility model employs a reverse spiral design for the cooling chamber and the return chamber, which are connected to a 180° U-shaped cavity, forming a complete counter-current heat exchange system. This ensures that the lower-temperature inlet water and the higher-temperature return water are always in adjacent flow channels, flowing in opposite directions and continuously exchanging heat. This keeps the temperature of the cold water entering the high-temperature zone lower than in traditional methods, while the return water also carries away more heat, maximizing the overall heat exchange efficiency.

[0013] 2. This utility model uses cross-arranged guide fins to periodically and actively disturb the water flow, transforming it from inefficient laminar flow to efficient turbulent flow. At the same time, the pressurized cavity can locally accelerate the water flow, further enhancing the turbulence effect and impact force, thereby achieving rapid, powerful and uniform cooling of the roller. This allows the equipment to operate at a higher speed, producing coating products with more stable quality, and directly improving production efficiency.

[0014] 3. This utility model uses weight blocks, which have no effect on the sealing ring when the drum is stationary. When the drum rotates at high speed, centrifugal force drives the weight blocks to slide outward. The four circumferential weight blocks work together, like an expansion ring, to squeeze the sealing ring from the inside out, making it fit more tightly with the circular sleeve. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a high-efficiency coating device for producing food packaging bags according to the present invention; Figure 2 This is a schematic diagram of the cooling mechanism of a high-efficiency coating device for food packaging bag production proposed in this utility model. Figure 3This is a cross-sectional view of the U-shaped cavity of a high-efficiency coating device for producing food packaging bags according to this utility model; Figure 4 This is a cross-sectional view of the cooling chamber of a high-efficiency coating device for food packaging bag production proposed in this utility model; Figure 5 This is a cross-sectional view of the guide fins of a high-efficiency coating device for producing food packaging bags according to this utility model; Figure 6 This is a schematic diagram of the sealing ring of a high-efficiency coating device for producing food packaging bags according to this utility model.

[0016] In the diagram: 1. Roller; 2. Cover plate; 3. Water inlet; 31. Sealing ring; 32. Circular sleeve; 33. Rectangular cavity; 34. Weight block; 4. Water outlet; 5. Cooling mechanism; 51. Cooling chamber; 52. Return chamber; 53. Threaded chamber; 54. U-shaped cavity; 55. Water pump; 56. Water pipe; 57. Guide fins; 58. Pressurization cavity. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0018] Reference Figures 1-6 A high-efficiency coating device for producing food packaging bags includes a roller 1, a cover plate 2, and a sealing ring 31. The roller 1 is provided with a cooling mechanism 5 for rapidly cooling the packaging bags on it. The cooling mechanism 5 includes a cooling chamber 51 for cooling the roller 1 and a return chamber 52 for recovering heated hot water.

[0019] The cooling mechanism 5 also includes a threaded cavity 53 formed inside the drum 1 for meshing and connecting the outer wall of the cooling cavity 51 with the outer wall of the return cavity 52. ​​Both the cooling cavity 51 and the return cavity 52 are spiral channels, and the cooling cavity 51 and the return cavity 52 are opposite spirals.

[0020] A positioning step is provided at the meshing end of the cooling chamber 51 and the return chamber 52. The flatness error of the step surface is controlled within 0.01mm to ensure that the flow channels of the cooling chamber 51 and the return chamber 52 are aligned after meshing, avoiding increased water flow resistance or local eddy problems caused by flow channel misalignment. A torque wrench is used to control the tightening torque during assembly to ensure tight meshing while facilitating subsequent disassembly and maintenance.

[0021] A 180° U-shaped cavity 54 is formed at the end of the cooling chamber 51 and the end of the return chamber 52. A water pump 55 is fixedly installed between the end of the cooling chamber 51 and the U-shaped cavity 54. The connection between the water pump 55 and the cooling chamber 51 and the U-shaped cavity 54 adopts a flange structure. The flange end face is machined with a sealing water line and has an internal fluororubber sealing gasket. It is fastened with four circumferentially distributed bolts to ensure no leakage under high-pressure water flow conditions. The base of the water pump 55 is connected to the bracket on the inner wall of the roller 1 through a shock-absorbing pad to reduce the vibration transmission during the operation of the water pump 55 and avoid affecting the stability of the flow channel. A water pipe 56 is fixedly installed between the return chamber 52 and the U-shaped cavity 54. The interface between the water pipe 56 and the flow channel is welded by argon arc welding. The weld joint is a V-shaped bevel. After welding, X-ray flaw detection is performed to ensure that there are no defects such as pores or cracks.

[0022] Both the cooling chamber 51 and the return chamber 52 are fixedly equipped with guide fins 57 for periodically disturbing the water flow and changing it from laminar to turbulent flow. The guide fins 57 are fixed to the inner walls of the flow channels of the cooling chamber 51 and the return chamber 52 by argon arc welding. The root of the fin is designed with a rounded transition structure to increase the welding contact area and improve the connection strength. A segmented welding process is used during welding to avoid concentrated heating that could cause deformation of the flow channel. The guide fins 57 ensure that the cold water in the center continuously impacts the inner walls of the hot cooling chamber 51 and the return chamber 52.

[0023] The guide fins 57 are semi-elliptical with a smooth leading edge and a sharp trailing edge. The guide fins 57 are arranged in a cross pattern, and the ratio of the flow length of the guide fins 57 to their spacing is controlled between 1:2 and 1:4. A pressurizing cavity 58 is provided in the middle of the guide fins 57 to increase the flow velocity of the water. The pressurizing cavity 58 has a pressurizing structure with a large opening and a small outlet.

[0024] The pressurizing cavity 58 is located in the middle of the guide fin 57 and has a gradually changing trumpet-shaped structure. The inlet diameter is half the width of the guide fin 57, and the outlet diameter is one-third to one-quarter of the inlet diameter. It utilizes the Venturi effect to achieve local acceleration of the water flow. The axis of the pressurizing cavity 58 is consistent with the direction of water flow. The inlet is equipped with a rounded transition to reduce water flow impact loss. The outlet is equipped with an inclined guide edge with an inclination angle of 30°-45° to guide the accelerated water flow to impact the thermal boundary layer of the inner wall of the flow channel at an oblique angle, thereby enhancing the turbulence disturbance effect.

[0025] The cover plate 2 is provided with a water inlet 3 for conveying cold water and a water outlet 4 for extracting backflow water. Both the water inlet 3 and the water outlet 4 are provided with centrifugal mechanisms to prevent the sealing ring 31 from falling off when the roller 1 rotates at high speed.

[0026] The centrifugal mechanism includes a circular sleeve 32 fixedly installed in the water inlet 3 and the water outlet 4 for fixing the sealing ring 31. The sealing ring 31 has four rectangular cavities 33 circumferentially open. A weight block 34 is slidably fitted on the rectangular cavity 33 to prevent the sealing ring 31 from falling off during high-speed rotation.

[0027] The weight block 34 and the rectangular cavity 33 on the sealing ring 31 are fitted with a clearance to ensure that the weight block 34 slides smoothly under centrifugal force. Limiting bosses with a height of 1-2 mm are provided at both ends of the weight block 34 to prevent it from sliding excessively and detaching from the rectangular cavity 33. Meanwhile, the weight block 34 can preferably be made of high-density tungsten alloy to enhance the centrifugal force effect within a limited volume and strengthen the compression effect on the sealing ring 31.

[0028] The cover plate 2 is fixedly installed on both sides of the drum 1, and four of them are provided. The cooling mechanism 5 is provided in two sets on the upper and lower sides of the drum 1. The cover plate 2 adopts a composite fixing method of positioning pins and circumferentially distributed high-strength bolts to achieve rigid connection with the end faces of both sides of the drum 1. Among them, the positioning pins are distributed in a circular array along the center of the cover plate 2, and there are four of them. This precisely controls the coaxiality error between the cover plate 2 and the drum 1 to within 0.02mm, so as to avoid centrifugal vibration caused by eccentricity during high-speed rotation.

[0029] It should be noted that the specific model and specifications of the water pump 55 need to be selected and determined based on the actual specifications of the device. The specific selection calculation method adopts the existing technology in this field, so it will not be elaborated here.

[0030] The functional principle of this utility model can be explained through the following operation methods: First, when the equipment is started, external cooling water is injected into the system through the water inlet 3 fixed on the cover plate 2. The cooling water then enters the cooling mechanism 5 integrated inside the drum 1.

[0031] Subsequently, cooling water first flows into the cooling chamber 51, where it flows in a spiral shape and absorbs heat from the outer wall of the drum 1. When it reaches the end and turns through the U-shaped cavity 54, the heated hot water flows back into the reverse spiral return chamber 52. During this process, the counter-current flow of cold and hot water in adjacent channels creates highly efficient counter-current heat exchange, allowing the cold water to be pre-cooled before entering the high-temperature zone, while the hot water releases heat to the maximum extent before flowing out, thus maximizing the overall heat exchange efficiency.

[0032] Meanwhile, the system actively enhances the heat exchange effect. As the cooling water flows through the cooling chamber 51 and the return chamber 52, it periodically impacts the guide fins 57 fixed to the inner wall of the flow channel. These cross-arranged semi-elliptical guide fins 57 actively disrupt the originally stable laminar flow, transforming it into chaotic turbulence. Turbulence effectively breaks down the stagnant thermal boundary layer near the pipe wall, allowing the cooler water at the center of the flow channel to continuously and violently impact the hot inner wall. Furthermore, the pressurization cavity 58 opened in the middle of the guide fins 57 utilizes the principle of being wider at the top and narrower at the bottom to further accelerate the water flow locally, enhancing the turbulence effect and impact force.

[0033] Furthermore, a water pump 55 is fixedly installed at the connection between the U-shaped cavity 54 and the cooling cavity 51. This water pump 55 provides power for the circulation of cooling water throughout the closed spiral loop. The heated cooling water eventually flows out from the return cavity 52 and is discharged through the water outlet 4 fixed on the other side cover plate 2, completing a complete cooling cycle.

[0034] Finally, the sealing reliability is fundamentally guaranteed throughout the entire high-speed operation. When the roller 1 is stationary or rotating at low speed, the load-bearing blocks 34 do not affect normal installation. Once the equipment enters a high-speed rotation state, centrifugal force will drive the four load-bearing blocks 34 to slide outward. They work together like a continuously expanding ring, continuously and evenly squeezing the sealing ring 31 from the inside out, so that the adhesion between the sealing ring 31 and the circular sleeve 32 continuously increases with the increase of rotation speed, thereby solving the problem of the sealing ring 31 loosening due to centrifugal force under high-speed conditions.

[0035] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A high-efficiency coating device for producing food packaging bags, comprising a roller (1), a cover plate (2), and a sealing ring (31), characterized in that, The drum (1) is provided with a cooling mechanism (5) for rapidly cooling the packaging bags on it. The cooling mechanism (5) includes a cooling chamber (51) for cooling the drum (1) and a return chamber (52) for recovering heated hot water. The cover plate (2) is provided with a water inlet (3) for conveying cold water and a water outlet (4) for extracting return water. Both the water inlet (3) and the water outlet (4) are provided with a centrifugal mechanism to prevent the sealing ring (31) from falling off when the drum (1) rotates at high speed.

2. The high-efficiency coating device for producing food packaging bags according to claim 1, characterized in that, The cover plate (2) is fixedly installed on both sides of the drum (1), and four of them are provided. The cooling mechanism (5) is provided in two sets on the upper and lower sides of the drum (1).

3. The high-efficiency coating device for producing food packaging bags according to claim 2, characterized in that, The cooling mechanism (5) includes a threaded cavity (53) opened in the drum (1) for meshing and connecting the outer wall of the cooling cavity (51) and the outer wall of the return cavity (52). The cooling cavity (51) and the return cavity (52) are both spiral channels, and the cooling cavity (51) and the return cavity (52) are opposite spirals.

4. The high-efficiency coating device for producing food packaging bags according to claim 3, characterized in that, A 180° U-shaped cavity (54) is provided at the end of the cooling cavity (51) and the end of the reflux cavity (52). A water pump (55) is fixedly installed between the end of the cooling cavity (51) and the U-shaped cavity (54). A water pipe (56) is fixedly installed between the reflux cavity (52) and the U-shaped cavity (54).

5. The high-efficiency coating device for producing food packaging bags according to claim 4, characterized in that, Both the cooling chamber (51) and the reflux chamber (52) are fixedly equipped with guide fins (57) for periodically disturbing the water flow and changing it from laminar flow to turbulent flow. The guide fins (57) cause the cold water at the center to continuously impact the inner walls of the hot cooling chamber (51) and the reflux chamber (52).

6. The high-efficiency coating device for producing food packaging bags according to claim 5, characterized in that, The guide fins (57) are semi-elliptical with a smooth front edge and a sharp rear edge. The guide fins (57) are arranged in a cross pattern, and the ratio of the flow length of the guide fins (57) to their spacing is controlled between 1:2 and 1:

4. A pressurizing cavity (58) for increasing the flow velocity is provided in the middle of the guide fins (57), and the pressurizing cavity (58) is a pressurizing structure with a large opening and a small outlet.

7. The high-efficiency coating device for producing food packaging bags according to claim 2, characterized in that, The centrifugal mechanism includes a circular sleeve (32) fixedly installed in the water inlet (3) and water outlet (4) for fixing the sealing ring (31). The sealing ring (31) has four rectangular cavities (33) circumferentially open. A weight block (34) is slidably fitted on the rectangular cavity (33) to prevent the sealing ring (31) from falling off when rotating at high speed.

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