Rapid cooling device for film production

Abstract

The invention provides a rapid cooling device for film production, and belongs to the technical field of medical material manufacturing equipment.The rapid cooling device comprises an outer shell, an inner shell and an inner shell, the multi-temperature-zone air outlet machine comprises independent air ducts of a high-temperature zone, a normal-temperature zone and a low-temperature zone; the protective gas main pipeline is connected with an external protective gas supply source and the high-temperature area, and a heating wire is arranged at an inlet section of the high-temperature area; the shunting pipeline is connected to an upstream unheated section of the heating wire of the protective gas main pipeline, is connected to the normal-temperature area through a first flow regulating valve and is connected to the low-temperature area through a second flow regulating valve; the heat exchanger is used for cooling the protective gas entering the low-temperature area, and a cold source connector of the heat exchanger penetrates out of the outer shell to be connected with external refrigeration equipment. The device has the advantages that through the segmented independent air duct design, the progressive gradient cooling of the film is realized in combination with the differentiated air duct sectional area proportion and the heat insulation isolation structure; and uneven shrinkage of the coating is effectively avoided, and the thermal stress damage risk of the silver halide coating is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical material manufacturing equipment, and particularly relates to a rapid cooling device for film production. Background Art

[0002] The core of a medical film is the uniform coating of a photosensitive emulsion (such as a silver halide coating). During the coating process, the emulsion needs to maintain fluidity at a certain temperature. After coating, it needs to undergo a gradient cooling process to prevent microcracks or bubble defects from occurring in the coating due to thermal stress.

[0003] Existing equipment mostly adopts an open-air cooling combined with natural cooling method. Its cooling rate is greatly restricted by the environmental temperature and humidity. At the outlet section of the drying oven, the surface temperature of the film is as high as 60 - 70°C. If directly exposed to an oxygen-containing environment, it will cause the silver halide crystals to undergo an oxidation blackening reaction, reducing the photosensitivity of the film.

[0004] The currently widely used cooling solutions in the industry have the following technical defects: 1. The single-temperature zone air supply system cannot achieve precise control of the temperature curve, and the rapid cooling process is prone to uneven shrinkage of the coating; 2. The air cooling medium contains 21% oxygen, which will accelerate the oxidation and deterioration of the photosensitive emulsion at high temperatures. Therefore, the applicant proposes a rapid cooling device for film production. Summary of the Invention

[0005] In view of this, in order to address the deficiencies of the prior art, the present invention provides a rapid cooling device for film production. To solve the above technical problems, the technical solution adopted by the present invention is as follows: It includes: an external housing with a film transmission channel running through it horizontally, and the film is arranged in the film transmission channel; a multi-temperature zone air blower installed inside the external housing, including independent air ducts for the high-temperature zone, normal-temperature zone, and low-temperature zone; a main protection gas pipeline connecting an external protection gas supply source to the high-temperature zone. The protection gas is an inert gas or a non-oxidizing gas, and a heating wire is provided at the inlet section of the high-temperature zone; a shunt pipeline connected to the unheated section upstream of the heating wire of the main protection gas pipeline, and connected to the normal-temperature zone through a first flow regulating valve and to the low-temperature zone through a second flow regulating valve; a heat exchanger arranged between the second flow regulating valve and the low-temperature zone for cooling the protection gas entering the low-temperature zone, and its cold source interface passes through the external housing and is connected to an external refrigeration device; a microporous flow guiding plate covering the air outlet of the multi-temperature zone air blower for evenly supplying air to the film transmission channel.

[0006] Further, the cross-sectional area ratio of the air ducts in the high-temperature zone, normal-temperature zone, and low-temperature zone of the multi-temperature zone air blower is 1:0.8:0.6, and heat insulation plates are provided between the zones.

[0007] Further, the heat exchanger is of a plate-fin structure, the fin pitch is 3 - 5 mm, the material is aluminum or copper, and the cold source is 5 - 15°C cold water.

[0008] Furthermore, the microporous flow guiding plate is a porous ceramic plate, with a polytetrafluoroethylene anti-sticking layer coated on its surface, and the thickness is 0.1 - 0.3 μm.

[0009] Furthermore, it also includes a controller. A temperature sensor and a humidity sensor are arranged inside the outer shell. The controller is used to receive the signals of the temperature sensor and the humidity sensor in real time, and dynamically adjust the power of the heating wire and the opening degrees of the first flow regulating valve and the second flow regulating valve.

[0010] Furthermore, arc-shaped guiding plates are arranged on both sides of the film inside the outer shell. The arc-shaped guiding plates guide the protective gas output from the high-temperature area to the bottom of the film, forming a surrounding airflow, and an air extraction pipeline is arranged below the film.

[0011] Furthermore, one end of the air extraction pipeline passes through the inside of the outer shell and is connected to an air extractor, and its rotation speed is adjustable within 500 - 1500 rpm.

[0012] An application method of the protective gas for film production, realized based on the rapid cooling device for film production, includes: Transport the protective gas with an oxygen concentration < 50 ppm to the high-temperature area through the main pipeline of the protective gas, and adjust the gas temperature to 45 - 55 °C through the heating wire; Allocate part of the unheated protective gas to the normal-temperature area and the low-temperature area through the shunt pipeline. Among them, the gas transported to the low-temperature area is cooled to 5 - 15 °C through the heat exchanger; The gases in the high-temperature area, normal-temperature area and low-temperature area take away the heat of the film, causing the film to gradually cool down; The gases in the high-temperature area, normal-temperature area and low-temperature area apply a laminar air film to the surface of the medical film through the microporous flow guiding plate, so that the oxygen concentration on the film surface ≤ 30 ppm; The protective gas inhibits the oxidation of the coating on the film surface.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Through the segmented independent air duct design of the high-temperature area, normal-temperature area and low-temperature area, combined with the differential air duct cross-sectional area ratio and the heat insulation and isolation structure, the progressive gradient cooling of the film is realized; this design effectively avoids the problem of uneven coating shrinkage caused by the traditional rapid cooling process, and reduces the risk of thermal stress damage to the silver halide coating.

[0014] 2. Using an inert gas as the cooling medium, through the synergistic effect of the pre-heated high-temperature gas and the heat-exchanged low-temperature gas, a laminar protective gas film that isolates oxygen is formed on the film surface. This technology fundamentally blocks the oxidation reaction path of the silver halide coating in the high-temperature section, and greatly improves the photosensitive stability of the film.

[0015] 3. An integrated sensor and control system that monitors in real time and dynamically adjusts the gas temperature, flow rate, and humidity parameters in each temperature zone. In combination with an exhaust system with adjustable speed, a closed-loop control mechanism is formed to ensure the cooling efficiency and oxidation inhibition effect under different production processes.

[0016] 4. A porous ceramic deflector plate treated by surface modification actively repels the adhesive droplets carried in the air flow through its low surface energy characteristics. This design is less likely to be contaminated compared to traditional metal deflector plates, ensuring the continuous and uniform distribution of the air flow, while reducing the frequency of equipment cleaning and maintenance; 5. Through the coordinated layout of the arc-shaped deflector plate and the bottom exhaust duct, a surrounding air flow channel covering the upper and lower surfaces of the film is constructed. Combining with the enhanced heat dissipation ability of the plate-fin heat exchanger, the heat exchange efficiency of the cooling medium is significantly improved, realizing a fast and uniform cooling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described in detail below with reference to the accompanying drawings.

[0018] Figure 1 : The three-dimensional structural schematic diagram of the present invention; Figure 2 : The structural schematic diagram of the cross-section under the left view of the present invention; Figure 3 : The structural schematic diagram of the cross-section under the front view of the present invention; Figure 4 : The structural schematic diagram of the air outlet fan of the present invention; Among them, 1. External housing; 2. Transmission channel; 3. Multi-temperature zone air outlet fan; 4. Main protection gas pipeline; 5. Shunt pipeline; 6. Heat exchanger; 7. Micro-hole deflector plate; 8. Controller; 9. Arc-shaped guiding plate; 11. Exhaust duct; 12. Exhaust fan; 31. High-temperature zone; 32. Normal-temperature zone; 33. Low-temperature zone; 34. Heat insulation plate; 41. Heating wire; 51. First flow regulating valve; 52. Second flow regulating valve; 61. Cold source interface; 81. Temperature sensor; 82. Humidity sensor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] In order to better understand the present invention, the content of the present invention will be further clearly elaborated below in combination with the embodiments and the drawings. However, the protected content of the present invention is not limited to the following embodiments only. In the following description, a large number of specific details are given to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details.

[0020] Example 1: Refer to Figures 1-4 , A rapid cooling device for film production in this embodiment includes: An external housing 1 is provided with a film transmission channel 2 running through it horizontally. The film transmission channel 2 arranged inside the external housing 1 adopts a horizontally penetrating structure, and the film is arranged inside the film transmission channel 2; A multi-temperature zone air blower 3 is installed inside the external housing 1 and above the film transmission channel 2, and includes independent air ducts for a high-temperature zone 31, a normal-temperature zone 32, and a low-temperature zone 33; the high-temperature zone 31, the normal-temperature zone 32, and the low-temperature zone 33 of the multi-temperature zone air blower 3 achieve temperature isolation through independent air ducts; A main protection gas pipeline 4 connects an external protection gas supply source to the high-temperature zone 31; the protection gas is an inert gas or a non-oxidizing gas, which is used to inhibit the oxidation of the silver halide coating. The protection gas needs to meet the requirement that it does not chemically react with silver halide at the operating temperature. The protection gas is selected from at least one of nitrogen, argon, helium, or carbon dioxide; a heating wire 41 is provided at the inlet section of its high-temperature zone 31, and the heating wire 41 connected to the main protection gas pipeline 4 pre-heats the gas in the high-temperature zone; A shunt pipeline 5 is connected to the unheated section upstream of the heating wire 41 of the main protection gas pipeline 4, and is connected to the normal-temperature zone 32 through a first flow regulating valve 51 and to the low-temperature zone 33 through a second flow regulating valve 52; the shunt pipeline 5 distributes gas to different temperature zones through the first flow regulating valve 51 and the second flow regulating valve 52; A heat exchanger 6 is arranged between the second flow regulating valve 52 and the low-temperature zone 33, and is used to cool the protection gas entering the low-temperature zone 33. Its cold source interface 61 passes through the external housing 1 and is connected to an external refrigeration device; A microporous flow guide plate 7 covers the air outlet of the multi-temperature zone air blower 3 and is used to evenly supply air to the film transmission channel 2. The heat exchanger 6 and the microporous flow guide plate 7 cooperate to complete gas temperature regulation and uniform air supply.

[0021] Refer to Figure 3 , the cross-sectional area ratios of the air ducts of the high-temperature zone 31, the normal-temperature zone 32, and the low-temperature zone 33 of the multi-temperature zone air blower 3 are 1:0.8:0.6, and heat insulation plates 34 are provided between the zones. The cross-sectional area ratios of the air ducts of the high-temperature zone 31, the normal-temperature zone 32, and the low-temperature zone 33 of the multi-temperature zone air blower 3 are optimized, and the heat insulation plates 34 provided between the zones are made of high-temperature resistant composite materials, effectively blocking heat transfer between the temperature zones.

[0022] Refer to Figures 3-4 , the heat exchanger 6 is of a plate-fin structure, the fin pitch is 3 - 5 mm, the material is aluminum or copper, the cold source is 5 - 15 °C cold water, the fin pitch of the plate-fin heat exchanger is verified by fluid simulation, and its cold source interface 61 is connected to an external refrigeration system. The preferably metal fin material reduces the gas flow pressure loss while ensuring the heat conduction efficiency.

[0023] Refer to Figures 2-3, the micro-porous flow guide plate 7 is a porous ceramic plate, with a polytetrafluoroethylene anti-sticking layer coated on its surface, having a thickness of 0.1 - 0.3 μm. During the drying process of the medical film, acrylate adhesives will be released. When air flow disturbances cause tiny droplets to splash, it reduces the adhesion force of the small droplets on the porous ceramic plate, and can still maintain the porosity unobstructed in an air flow disturbance environment, preventing the deposition of adhesives.

[0024] Refer to Figure 3 , it further includes a controller 8. A temperature sensor 81 and a humidity sensor 82 are provided inside the external housing 1. The controller 8 is used to receive the signals of the temperature sensor 81 and the humidity sensor 82 in real time, and dynamically adjust the power of the heating wire 41 and the opening degrees of the first flow regulating valve 51 and the second flow regulating valve 52. By adjusting the power of the heating wire 41 and the opening degrees of the flow regulating valves, a multi-temperature zone dynamic balance is achieved.

[0025] Refer to Figures 2-3 , arc-shaped guide plates 9 are provided on both sides of the film inside the external housing 1. The arc-shaped guide plates 9 direct the protective gas output from the high-temperature zone 31 to the bottom of the film, forming a circumferential air flow. An exhaust duct 11 is provided below the film. The curved surface of the arc-shaped guide plate 9 guides the air flow in the high-temperature zone 31 to the bottom of the film. The exhaust duct 11 and the arc-shaped guide plate 9 form a convection channel to enhance the heat dissipation effect.

[0026] Refer to Figure 1 , one end of the exhaust duct 11 passes through the inside of the external housing 1 and is connected to an exhaust fan 12, whose rotational speed is adjustable at 500 - 1500 rpm. The exhaust fan 12 connected to the end of the exhaust duct 11 adopts a variable frequency speed regulation design. The controller 8 can also adjust the gas circulation rate according to the process requirements to maintain the system pressure balance.

[0027] Technical effects of this embodiment: 1. The inert gas is transported to the high-temperature zone 31 through the main protective gas pipeline 4, and the heating wire 41 pre-heats the gas. At this stage, a high-temperature inert gas barrier is formed, which immediately isolates the contact with oxygen when the film enters the cooling zone, blocking the silver halide oxidation reaction from the source.

[0028] 2. The shunt pipeline 5 transports the unheated gas to the normal-temperature zone 32 and the low-temperature zone 33 cooled by the heat exchanger 6 respectively through the flow regulating valves. This staged temperature control mechanism enables the film to experience a gradient cooling, avoiding the sudden change of coating stress caused by traditional single-temperature zone cooling.

[0029] 3. Through the uniform flow action of the micro-porous flow guide plate 7, the gas in each temperature zone covers the surface of the film in a stable laminar flow form. The anti-sticking property of the porous ceramic plate simultaneously blocks the reverse adhesion pollution of the adhesive, ensures the continuous unobstructedness of the air flow channel, and maintains a constant oxygen concentration inhibition environment.

[0030] 4. The air flow in the high-temperature zone 31 passes through the arc-shaped guide plate 9 to the bottom of the film, and forms a two-way convection with the negative pressure area formed by the exhaust duct 11. In cooperation with the adjustable speed of the exhaust fan 12, the directional circulation of the air flow in the transmission channel 2 is realized, and the heat exchange efficiency is improved.

[0031] 5. The temperature sensor 81 and the humidity sensor 82 monitor the status of each temperature zone in real time, and the controller 8 dynamically coordinates the power of the heating wire 41, the first flow regulating valve 51, the second flow regulating valve 52 and the speed of the exhaust fan 12 through algorithms. This closed-loop control ensures that the temperature drop curve is precisely controllable under different production conditions, and at the same time maintains the stability of the oxygen concentration of the protective gas.

[0032] Embodiment 2: The application method of the protective gas for film production is realized based on the rapid cooling device for film production, and it includes: The protective gas with an oxygen concentration < 50 ppm is transported to the high-temperature zone 31 through the main protective gas pipeline 4, and the gas temperature is adjusted to 45 - 55 °C through the heating wire 41; Part of the unheated protective gas is distributed to the normal-temperature zone 32 and the low-temperature zone 33 through the shunt pipeline 5, and the gas transported to the low-temperature zone 33 is cooled to 5 - 15 °C through the heat exchanger 6; The gas in the high-temperature zone 31, the normal-temperature zone 32 and the low-temperature zone 33 takes away the heat of the film to gradually cool the film; The gas in the high-temperature zone 31, the normal-temperature zone 32 and the low-temperature zone 33 applies a laminar gas film to the surface of the medical film through the microporous flow guide plate 7, so that the oxygen concentration on the film surface ≤ 30 ppm, The protective gas inhibits the oxidation of the coating on the film surface.

[0033] The technical effects of this embodiment: The protective gas enters the high-temperature zone 31 after being heated by the main protective gas pipeline 4, and the shunt pipeline 5 distributes the unheated gas to the normal-temperature zone 32 and the low-temperature zone 33 processed by the heat exchanger 6. The laminar gas film formed by the microporous flow guide plate 7 realizes the full-process inert gas protection.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Any other modifications or equivalent replacements made by those of ordinary skill in the art to the technical solutions of the present invention shall be covered within the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solutions of the present invention.

Claims

1. A rapid cooling device for film production, characterized in that, Comprising: An outer housing (1) with a film transmission channel (2) running horizontally through it internally, and the film is disposed within the film transmission channel (2); A multi-temperature zone air blower (3) installed inside the outer housing (1), including independent air ducts for a high-temperature zone (31), a normal-temperature zone (32), and a low-temperature zone (33); A main protective gas pipeline (4) connecting an external protective gas supply source to the high-temperature zone (31), the protective gas being an inert gas or a non-oxidizing gas, and a heating wire (41) being provided at the inlet section of the high-temperature zone (31); A shunt pipeline (5) connected to the unheated section upstream of the heating wire (41) of the main protective gas pipeline (4), and accessing the normal-temperature zone (32) through a first flow regulating valve (51) and accessing the low-temperature zone (33) through a second flow regulating valve (52); A heat exchanger (6) disposed between the second flow regulating valve (52) and the low-temperature zone (33) for cooling the protective gas entering the low-temperature zone (33), and its cold source interface (61) passing through the outer housing (1) to connect to an external refrigeration device; A microporous flow guiding plate (7) covering the air outlet of the multi-temperature zone air blower (3) for evenly supplying air to the film transmission channel (2).

2. The rapid cooling device for film production according to claim 1, characterized in that, The air duct cross-sectional area ratio of the high-temperature zone (31), the normal-temperature zone (32), and the low-temperature zone (33) of the multi-temperature zone air blower (3) is 1:0.8:0.6, and heat insulation plates (34) are provided between the zones.

3. The rapid cooling device for film production according to claim 1, characterized in that The heat exchanger (6) is of a plate-fin structure, with a fin pitch of 3 - 5 mm, made of aluminum or copper, and the cold source is 5 - 15 °C cold water.

4. The rapid cooling device for film production according to claim 1, characterized in that, The microporous flow guiding plate (7) is a porous ceramic plate with a polytetrafluoroethylene anti-sticking layer coated on its surface, and the thickness is 0.1 - 0.3 μm.

5. The rapid cooling device for film production according to claim 1, characterized in that, It further includes a controller (8), a temperature sensor (81) and a humidity sensor (82) are provided inside the outer housing (1), and the controller (8) is used to receive the signals of the temperature sensor (81) and the humidity sensor (82) in real time and dynamically adjust the power of the heating wire (41) and the opening degrees of the first flow regulating valve (51) and the second flow regulating valve (52).

6. The rapid cooling device for film production according to claim 1, wherein Arc-shaped guiding plates (9) are provided on both sides of the film inside the outer housing (1), and the arc-shaped guiding plates (9) guide the protective gas output from the high-temperature zone (31) to the bottom of the film to form a surrounding airflow, and an air extraction pipeline (11) is provided below the film.

7. The rapid cooling device for film production according to claim 6, characterized in that, One end of the air extraction pipeline (11) passes through the inside of the outer housing (1) and is connected to an air extraction fan (12), and its rotational speed is adjustable between 500 - 1500 rpm.

8. Application method of protective gas for film production, realized based on the rapid cooling device for film production according to any one of claims 1-7, characterized in that, Comprising: Transporting a protective gas with an oxygen concentration < 50 ppm through the main protective gas pipeline (4) to the high-temperature zone (31), and adjusting the gas temperature to 45 - 55 °C through the heating wire (41); Allocating part of the unheated protective gas to the normal-temperature zone (32) and the low-temperature zone (33) through the shunt pipeline (5), and the gas transported to the low-temperature zone (33) is cooled to 5 - 15 °C through the heat exchanger (6); The gas in the high-temperature zone (31), normal-temperature zone (32) and low-temperature zone (33) takes away the heat of the film to gradually cool the film; The gas in the high-temperature zone (31), normal-temperature zone (32) and low-temperature zone (33) applies a laminar gas film to the surface of the medical film through the microporous flow guide plate (7), so that the oxygen concentration on the film surface is ≤ 30 ppm, The protective gas inhibits the oxidation of the coating on the film surface.

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