Nitrogen drying oven capable of keeping clean for long time and control method of nitrogen drying oven

Abstract

The invention provides a nitrogen oven capable of keeping clean for a long time and a control method thereof. The nitrogen oven comprises an oven body, a top frame fixed to the top of the oven body, a pollution discharge device, a cooling device, a nitrogen injection device and a monitoring device. And a control device electrically connected with the pollution discharge device, the cooling device, the nitrogen injection device and the monitoring device is embedded in the outer surface of the box body. According to the nitrogen consumption saving measure, the intelligent controller determines to open one path of nitrogen or multiple paths of nitrogen according to the configuration of multiple paths of nitrogen and the judgment of the oxygen concentration value obtained by the intelligent controller and the oxygen concentration analyzer, the multiple paths of nitrogen are configured according to different flow rates, and a large-flow nitrogen channel is closed in the constant-temperature stage. The temperature and the oxygen concentration in the box are kept at the right appropriate flow, the performance of equipment and the required oxygen concentration range during baking are guaranteed, and the nitrogen consumption is also saved.

Description

Technical Field

[0001] The invention relates to the field of nitrogen ovens, and in particular to a nitrogen oven capable of maintaining long-term cleanliness and a control method thereof. Background Art

[0002] Nitrogen oven equipment is used for special process requirements such as high-temperature curing and baking of precision electronic components, PI, BCB glue, photoresist curing, and dust-free drying of electronic ceramic materials. It is suitable for touch screens, wafers, LEDs, PCB boards, ITO glass and other precision electronics, solar energy, new materials and other industries. When users use nitrogen ovens for high-temperature curing and baking of precision electronic components, PI, BCB glue, photoresist curing and other process treatments, the resin or other adhesive materials contained in the user's product itself will volatilize a large amount of sticky volatiles after high-temperature baking.

[0003] However, similar nitrogen ovens on the market currently have the following problems: None of them have a good volatile matter emission treatment design. Basically, a large amount of sticky matter will be generated on the inner wall of the oven after a short period of use, and it cannot be treated, which shortens the service life and replacement cycle of the oven equipment.

[0004] The loss of nitrogen is particularly large because there is no good nitrogen dosage allocation mechanism design. During use, nitrogen is delivered at no cost to ensure a low oxygen concentration in the inner cavity.

[0005] Therefore, for the above two problems, a nitrogen oven is needed to solve the emission problem of volatiles during baking, as well as a nitrogen oven product with the ability to save nitrogen usage, so that users can extend the equipment replacement and maintenance cycle, reduce energy consumption and thus reduce users' long-term use costs. Summary of the invention

[0006] In view of the technical defects existing in the background technology, the present invention proposes a nitrogen oven capable of maintaining long-term cleanliness and a control method thereof, which solves the above technical problems and meets the actual needs. The specific technical solution is as follows: A nitrogen oven capable of maintaining long-term cleanliness comprises a box body, a top frame fixed on the top of the box body, a sewage discharge device, a cooling device, a nitrogen injection device and a monitoring device, wherein the outer surface of the box body is inlaid with a control device electrically connected to the sewage discharge device, the cooling device, the nitrogen injection device and the monitoring device respectively, the sewage discharge device comprises a circulation fan installed inside the box body, a sewage discharge port and a sewage discharge fan provided on the upper surface of the top frame, the nitrogen injection device comprises a plurality of nitrogen injection ports, a flow meter and a gas source pressure monitoring device, the input end of the flow meter is externally connected to a nitrogen source and the output end is connected to the nitrogen injection port, the gas source pressure monitoring device is used to detect the pressure of nitrogen, a balancing port for balancing the pressure is provided on the top of the box body, and an oxygen concentration analyzer is provided on the outer surface of the box body.

[0007] Furthermore, the cooling device includes a cooling fan installed on the upper surface of the top frame and a cooling pipe laid inside the box.

[0008] Furthermore, the monitoring device includes an over-temperature protector and a pressure monitoring switch. The over-temperature protector is provided with several temperature monitoring points inside the box to prevent the temperature from exceeding the upper limit. The pressure monitoring switch is provided with several pressure monitoring points inside the box to monitor the air pressure inside the box.

[0009] Furthermore, the box body includes an inner box and an aluminum outer box, and two rows of corresponding card slots are arranged in the inner box.

[0010] Furthermore, a sealing door is provided at the front end of the inner box, one end of the sealing door is hinged to one end of the inner box and the other end is movably connected to the inner box through a double door lock, and the double door lock is electrically connected to the control device.

[0011] Furthermore, a three-color light is arranged on the top of the top frame, and a buzzer cooperating with the three-color light is installed inside the box.

[0012] Furthermore, a control cabinet is installed on one side of the inner box, an emergency stop switch is arranged at the front end of the control cabinet, and a heater is arranged at the bottom of the inner box.

[0013] Furthermore, a plurality of universal wheels are arranged at the bottom of the box.

[0014] A control method, comprising: Step S1, placing the product to be baked into the inner box, locking the sealing door, and starting the control device; Step S2, the control device controls the flow meter to connect to the nitrogen source to input a fixed flow of nitrogen into the inner box through the nitrogen injection port, starts the heater to heat the inner box, starts the over-temperature protector, the pressure monitoring switch and the oxygen concentration analyzer, wherein the nitrogen from the nitrogen source will be pre-pressurized by the pressure regulating component before being sent into the flow meter; Step S3, when the average value of all temperature monitoring points in the over-temperature protector reaches a preset threshold, the sewage discharge device is turned on, and when the oxygen concentration monitored by the oxygen concentration analyzer reaches a preset threshold, a portion of the nitrogen injection port channels are closed to reduce the amount of nitrogen injected; Step S4, when the sewage discharge device starts to reach the set time, the sewage discharge device is closed, and the heater keeps the products in the inner box at a certain temperature and bakes for a certain time. The control device controls the three-color light to change color, the buzzer to turn on, and the sealed door to open. At this point, the product is baked, and the cooling device is turned on to quickly reduce the temperature in the box to facilitate the baking of the next batch of products.

[0015] Compared with the prior art, the nitrogen oven capable of maintaining long-term cleanliness and the control method thereof provided by the present invention have the following beneficial effects: 1. During the baking stage, the present invention uses a specially designed sewage discharge structure and a control device to open the sewage discharge at the temperature where the volatiles of the user's baking materials are the most, and discharge most of the volatile substances out of the box in time. Through comparative testing with ordinary nitrogen ovens, this function can keep the interior of the equipment clean for a long time, and the cycle of replacing the equipment due to internal dirtiness caused by volatiles in the oven is extended by more than double.

[0016] 2. The nitrogen consumption saving measure of the present invention is to configure multiple nitrogen channels, and judge the oxygen concentration value obtained by intelligent control and oxygen concentration analyzer. The intelligent controller decides to open one nitrogen channel or multiple nitrogen channels. The multiple nitrogen channels are configured with different flow rates. The nitrogen channel with large flow rate is closed in the constant temperature stage, and the temperature and oxygen concentration in the box are maintained at a just appropriate flow rate, which ensures the performance of the equipment and the oxygen concentration range required for baking, and also saves the nitrogen consumption. After the same baking process is completed, the oven can save 1 / 2 of the nitrogen consumption compared with ordinary nitrogen ovens. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure is a schematic diagram of the structure of a nitrogen oven capable of maintaining long-term cleanliness in the present invention.

[0018] Figure 2 The figure is a front view of a nitrogen oven capable of maintaining long-term cleanliness in the present invention.

[0019] Figure 3 The present invention is a schematic diagram of a nitrogen oven capable of maintaining long-term cleanliness with its sealed door opened.

[0020] Figure 4 It is a structural schematic diagram of the sewage discharge device in the present invention.

[0021] Figure 5 It is a schematic structural diagram of the sewage discharge device in the present invention from another angle.

[0022] Figure 6 This is a schematic structural diagram of another angle of a nitrogen oven capable of maintaining long-term cleanliness according to the present invention with its sealed door opened.

[0023] Among them, 1. box body, 2. top frame, 3. circulation fan, 4. sewage outlet, 5. sewage fan, 6. flow meter, 7. balance port, 8. oxygen concentration analyzer, 9. cooling fan, 10. cooling pipe, 11. over-temperature protector, 12. pressure monitoring switch, 13. inner box, 14. outer shell, 15. card slot, 16. sealed door, 17. double door lock, 18. control device, 19. three-color light, 20. control cabinet, 21. emergency stop switch, 22. heater, 23. universal wheel. DETAILED DESCRIPTION

[0024] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "middle", "inside", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, it should be noted that, unless otherwise clearly specified and defined, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0025] The implementation modes of the present invention are described below in conjunction with the accompanying drawings and relevant embodiments. The implementation modes of the present invention are not limited to the following embodiments, and the present invention relates to relevant necessary components in the technical field, which should be regarded as the known technology in the technical field and can be known and mastered by the technical personnel in the technical field.

[0026] See also Figure 1-6A nitrogen oven capable of maintaining long-term cleanliness comprises a box body 1, a top frame 2 fixed on the top of the box body 1, a sewage discharge device, a cooling device, a nitrogen injection device and a monitoring device. The outer surface of the box body 1 is inlaid with a control device 18 electrically connected to the sewage discharge device, the cooling device, the nitrogen injection device and the monitoring device respectively. The control device 18 comprises an intelligent controller and a display screen and a button switch inlaid on the box body 1. The sewage discharge device comprises a circulation fan 3 installed inside the box body 1, a sewage discharge port 4 and a sewage discharge fan 5 provided on the upper surface of the top frame 2. The nitrogen injection device comprises a plurality of nitrogen injection ports, a flow meter 6 and a gas source pressure monitoring device. The input end of the flow meter 6 is externally connected to a nitrogen source and the output end is connected to the nitrogen injection port. The gas source pressure monitoring device is used to detect the pressure of nitrogen. A balancing port 7 for balancing the pressure is provided on the top of the box body 1. An oxygen concentration analyzer 8 is provided on the outer surface of the box body 1.

[0027] In one embodiment of the present invention, the cooling device includes a cooling fan 9 installed on the upper surface of the top frame 2 and a cooling pipe 10 laid inside the box 1. The cooling fan 9 can quickly reduce the temperature inside the box 1 through the cooling pipe 10 after baking is completed, so as to facilitate baking of the next batch of products.

[0028] In one embodiment of the present invention, the monitoring device includes an over-temperature protector 11 and a pressure monitoring switch 12. The over-temperature protector 11 is provided with a plurality of temperature monitoring points inside the box 1 to prevent the temperature from exceeding the upper limit, and the pressure monitoring switch 12 is provided with a plurality of pressure monitoring points inside the box 1 to monitor the air pressure inside the box 1. The over-temperature protector 11 is used to monitor the temperature inside the box 1 in real time, and the pressure monitoring switch 12 can monitor the pressure value inside the box 1 in real time.

[0029] In one embodiment of the present invention, the box body 1 includes an inner box 13 and an aluminum outer shell 14. Two rows of corresponding slots 15 are arranged in the inner box 13. The slots 15 can be used to place baking plates, and the products to be baked can be placed on the baking plates.

[0030] In one embodiment of the present invention, a sealed door 16 is provided at the front end of the inner box 13, one end of the sealed door 16 is hinged to one end of the inner box 13 and the other end is movably connected to the inner box 13 through a double door lock 17, and the double door lock 17 is electrically connected to a control device 18. The double door lock 17 includes an electronic lock fixed to the inner box 13, and can be automatically closed and opened through the control device 18.

[0031] In one embodiment of the present invention, a three-color light 19 is disposed on the top of the top frame 2 , and a buzzer cooperating with the three-color light 19 is installed inside the box body 1 .

[0032] In one embodiment of the present invention, a control cabinet 20 is installed on one side of the inner box 13, and the control cabinet 20 is used to install the main circuit of the oven and the control device 18. An emergency stop switch 21 is provided at the front end of the control cabinet 20, and the device can be immediately shut down by the emergency stop switch 21. A heater 22 is provided at the bottom of the inner box 13, and the heater 22 is used to heat the material in the box body 1.

[0033] In one embodiment of the present invention, a plurality of universal wheels 23 are provided at the bottom of the box body 1 for easy movement.

[0034] A control method for a nitrogen oven capable of maintaining long-term cleanliness comprises: Step S1, put the product to be baked into the inner box 13, lock the sealing door 16, and start the control device 18; Step S2, the control device 18 controls the flow meter 6 to connect to the nitrogen source to input a fixed flow of nitrogen into the inner box 13 through the nitrogen injection port, starts the heater 22 to heat the inner box 13, starts the over-temperature protector 11, the pressure monitoring switch 12 and the oxygen concentration analyzer 8, wherein the nitrogen from the nitrogen source will be preliminarily sent to the flow meter 6 after being subjected to a constant pressure through the pressure regulating component; Step S3, when the average value of all temperature monitoring points in the over-temperature protector 11 reaches a preset threshold, the sewage discharge device is turned on, and when the oxygen concentration monitored by the oxygen concentration analyzer 8 reaches a preset threshold, a part of the nitrogen injection port channels are closed to reduce the injection amount of nitrogen; Step S4, when the sewage discharge device starts to reach the set time, the sewage discharge device is closed, and the heater 22 keeps the product in the inner box 13 at a certain temperature for a certain time. The control device 18 controls the three-color light 19 to change color, the buzzer to turn on, and the sealing door 16 to open. At this point, the product is baked, and the cooling device is turned on to quickly reduce the temperature in the box 1 to facilitate the baking of the next batch of products.

[0035] Working principle of the oven: Heated air is extracted from the air duct at the heater 22 at the bottom of the inner box 13 through the circulating fan 3, and high-purity nitrogen is sprayed into the nitrogen inlet, blown out from the right side through the fan blades, and then refluxed from the left side. The top sewage outlet 4 discharges the sticky volatile substances produced by the baked items during baking from the inner box 13 in a timely manner through logical control. The balance port 7 ensures that the pressure in the box is constant when nitrogen is introduced. The multi-point temperature monitoring 12 arranges 6 to 9 temperature monitoring points in various places in the box to monitor the uniform temperature distribution in the box in real time.

[0036] The main operation and general operation flow of the oven when working: open the oven sealed door 16, put in the baked product, close the oven sealed door 16 and lock the oven door with the double door lock 17 device, operate our controller to start the operation, at this time, the oven's safety electronic door lock will lock the oven sealed door 16 to prevent accidental opening. At the same time, after the nitrogen is constant pressure by the pressure regulating component, it will be adjusted to a fixed flow rate by the flow meter 6 and then introduced into the box through the nitrogen injection port, and the excess air in the box will be gradually discharged from the balance port 7 by the nitrogen introduced. The heater 22 also heats the circulating gas in the box at the same time. When the required baking temperature is reached, it is maintained for a period of time. The pressure switch will detect the pressure in the box in real time. The over-temperature protector 11 detects the temperature in the box in real time to see if it is within the specified temperature range to prevent the temperature from exceeding the upper limit. The gas source pressure detection will monitor the pressure of the nitrogen source in real time to prevent the nitrogen supply from being unstable and affecting the baking process requirements. After the baking constant time is completed, it enters the cooling and material taking stage. At this time, the top cooling fan 9 starts to exhaust and cool down. When the temperature drops to a value that can take and put the baking materials, the door safety lock device will be unlocked, and the door will be opened manually to take and put the materials. After the entire baking, the three-color light 19 begins to change from green to yellow, and the buzzer sounds to remind you to take the materials.

[0037] During the baking stage, the present invention uses a specially designed sewage discharge structure to open the sewage discharge at the temperature where the volatiles of the user's baking materials are the most through the control device 18, and discharges most of the volatile substances out of the oven in time. Through comparative testing with ordinary nitrogen ovens, this function can keep the interior of the equipment clean for a long time, and the cycle of replacing the equipment due to internal dirtiness caused by volatiles in the oven is extended by more than double.

[0038] The nitrogen consumption saving measure of the present invention is to configure multiple nitrogen channels, and judge the oxygen concentration value obtained by intelligent control and oxygen concentration analyzer 8. The intelligent controller decides to open one nitrogen channel or multiple nitrogen channels. The multiple nitrogen channels are configured with different flow rates. The nitrogen channel with large flow rate is closed in the constant temperature stage, and the temperature and oxygen concentration in the box are maintained at a just appropriate flow rate, which ensures the performance of the equipment and the oxygen concentration range required during baking, and also saves the nitrogen consumption. After the same baking process is completed, the oven can save 1 / 2 of the nitrogen consumption compared with the ordinary nitrogen oven.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A nitrogen oven capable of maintaining long-term cleanliness, characterized in that: The invention comprises a box body (1), a top frame (2) fixed on the top of the box body (1), a sewage discharge device, a cooling device, a nitrogen injection device and a monitoring device. The outer surface of the box body (1) is inlaid with a control device (18) which is electrically connected to the sewage discharge device, the cooling device, the nitrogen injection device and the monitoring device respectively. The sewage discharge device comprises a circulation fan (3) installed inside the box body (1), a sewage discharge port (4) and a sewage discharge fan (5) provided on the upper surface of the top frame (2). The nitrogen injection device comprises a plurality of nitrogen injection ports, a flow meter (6) and a gas source pressure monitoring device. The input end of the flow meter (6) is externally connected to a nitrogen source and the output end is connected to the nitrogen injection port. The gas source pressure monitoring device is used to detect the pressure of nitrogen. The top of the box body (1) is provided with a balancing port (7) for balancing the pressure. The outer surface of the box body (1) is provided with an oxygen concentration analyzer (8).

2. A nitrogen oven capable of maintaining long-term cleanliness according to claim 1, characterized in that: The cooling device comprises a cooling fan (9) installed on the upper surface of the top frame (2) and a cooling pipe (10) laid inside the box body (1).

3. A nitrogen oven capable of maintaining long-term cleanliness according to claim 1, characterized in that: The monitoring device comprises an over-temperature protector (11) and a pressure monitoring switch (12); the over-temperature protector (11) is provided with a plurality of temperature monitoring points inside the box (1) to prevent the temperature from exceeding an upper limit; the pressure monitoring switch (12) is provided with a plurality of pressure monitoring points inside the box (1) to monitor the air pressure inside the box (1).

4. A nitrogen oven capable of maintaining long-term cleanliness according to claim 1, characterized in that: The box body (1) comprises an inner box (13) and an aluminum outer shell (14), and two rows of corresponding card slots (15) are arranged in the inner box (13).

5. A nitrogen oven capable of maintaining long-term cleanliness according to claim 4, characterized in that: A sealing door (16) is provided at the front end of the inner box (13); one end of the sealing door (16) is hinged to one end of the inner box (13) and the other end is movably connected to the inner box (13) via a double door lock (17); the double door lock (17) is electrically connected to a control device (18).

6. A nitrogen oven capable of maintaining long-term cleanliness according to claim 1, characterized in that: A three-color light (19) is provided on the top of the top frame (2), and a buzzer that cooperates with the three-color light (19) is installed inside the box (1).

7. A nitrogen oven capable of maintaining long-term cleanliness according to claim 4, characterized in that: A control cabinet (20) is installed on one side of the inner box (13), an emergency stop switch (21) is provided at the front end of the control cabinet (20), and a heater (22) is provided at the bottom of the inner box (13).

8. A nitrogen oven capable of maintaining long-term cleanliness according to claim 1, characterized in that: A plurality of universal wheels (23) are arranged at the bottom of the box body (1).

9. A control method, applicable to a nitrogen oven capable of maintaining long-term cleanliness as claimed in any one of claims 1 to 8, characterized in that: include: Step S1, placing the product to be baked into the inner box (13), locking the sealing door (16), and starting the control device (18); Step S2, the control device (18) controls the flow meter (6) to connect to the nitrogen source to input a fixed flow of nitrogen into the inner box (13) through the nitrogen injection port, starts the heater (22) to heat the inner box (13), starts the over-temperature protector (11), the pressure monitoring switch (12) and the oxygen concentration analyzer (8), wherein the nitrogen from the nitrogen source is preliminarily sent to the flow meter (6) after being subjected to a constant pressure by a pressure regulating component; Step S3, when the average value of all temperature monitoring points in the over-temperature protector (11) reaches a preset threshold value, the sewage discharge device is turned on, and when the oxygen concentration monitored by the oxygen concentration analyzer (8) reaches a preset threshold value, a portion of the nitrogen injection port channels are closed to reduce the amount of nitrogen injected; Step S4, when the sewage discharge device reaches the set time, the sewage discharge device is closed, and the heater (22) keeps the products in the inner box (13) at a certain temperature for a certain time. The control device (18) controls the three-color light (19) to change color, the buzzer to turn on, and the sealing door (16) to open. At this point, the baking of the products is completed, and the cooling device is turned on to quickly reduce the temperature in the box (1) to facilitate the baking of the next batch of products.

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