A food sterilizer control system

Abstract

The present invention discloses a food sterilizer control system, comprising: a sensor unit for detecting the water injection volume information, internal water vapor temperature information, and real-time pressure information inside the sterilizer tank when in operation; a controller for receiving data information transmitted by the sensor unit, and for performing real-time control of the heating, sterilization, cooling, and drainage stages of the sterilizer tank based on the received temperature and pressure information; and a valve assembly for receiving instruction information transmitted by the controller, and for controlling the opening and closing of the gas discharge pipeline and the liquid discharge pipeline on the sterilizer tank. This sterilizer sterilizes using high-temperature steam, and the high-temperature steam has no contact with the actual object, which can achieve high-temperature sterilization while avoiding bacterial contact contamination. Therefore, the color, flavor, and texture of the food in the package are not damaged, and the corrosion of the packaged food is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of food sterilizers, and in particular to a food sterilizer control system. Background Art

[0002] Vacuum-packed food is a process where all the air in the packaging container is completely removed and sealed, maintaining a highly decompressed state inside the bag. The lack of air is equivalent to a low oxygen level, making it impossible for microorganisms to survive, thus ensuring that the fruit is fresh and free of disease and rot. Sterilization, on the other hand, uses physical or chemical methods to kill all microorganisms, including pathogenic microorganisms, non-pathogenic microorganisms, and spores.

[0003] Ultrahigh-pressure processing requires very specialized equipment. For example, orange juice may be processed in a pressure chamber and then aseptically filled into pre-sterilized packaging. Furthermore, ultrahigh-pressure processing must consider the type of microorganism, product characteristics, the desired process (pasteurization or commercial sterilization), and the product's distribution method. While ultrahigh-pressure processing is very effective against growing bacteria, yeast, and mold, spores are not inactivated by high pressure and require additional heating or other treatments to achieve high levels of kill. Another existing method for sterilizing canned food is flame sterilization, which involves high-temperature flame burning. However, this method can be difficult to control the sterilization temperature. Summary of the Invention

[0004] In view of the problems existing in the prior art, the present invention discloses a food sterilizer control system, comprising:

[0005] A sensor unit for detecting water injection information, internal water vapor temperature information, and real-time pressure information in the sterilizer tank when in operation;

[0006] a controller that receives data information transmitted by the sensor unit, and that performs real-time control of the heating, sterilization, cooling, and drainage stages of the sterilizer tank based on the received temperature and pressure information;

[0007] The valve assembly receives the instruction information transmitted by the controller, and controls the opening and closing of the gas discharge pipeline and the liquid discharge pipeline on the sterilizer tank.

[0008] Furthermore, the sensor unit includes at least a flow sensor for detecting the amount of water injected into the sterilizer tank, a bottom temperature sensor for detecting the temperature information around the heating wire, an exhaust temperature sensor for measuring the internal temperature information of the exhaust pipe, a pressure sensor for detecting the internal pressure information of the sterilizer tank, and a steam temperature sensor for detecting the steam temperature information in the tank during the sterilization process.

[0009] Furthermore, the valve assembly includes at least a safety valve assembly, an air intake solenoid valve, a drain valve, an exhaust valve and a water injection solenoid valve. The safety valve assembly and the air intake solenoid valve are installed on the gas delivery pipeline on the sterilizer tank, the drain valve is installed on the liquid discharge pipeline, and the exhaust valve is installed on the gas discharge pipeline, wherein the liquid discharge pipeline where the drain valve is located is connected to the gas discharge pipeline where the exhaust valve is located, and a sterilizer drain port is provided at the connected outlet, and the water injection solenoid valve is installed on the water inlet pipe of the sterilizer tank.

[0010] The system also includes a heating wire arranged inside the sterilizer tank to heat the sterilizer tank and a piston pump for pressurizing the sterilizer tank.

[0011] It also includes a heating thyristor and a heating relay, which are connected to the heating wire, and the controller controls the operation of the heating relay and the heating thyristor.

[0012] It also includes a sudden jump temperature controller, which controls the heating wire to stop working when the temperature of the tank bottom exceeds the sudden jump temperature threshold when the sterilizer is heating.

[0013] The device also includes a cooling fan connected to the controller.

[0014] It also includes a pressure gauge for displaying the internal pressure information of the sterilizer tank; the pressure gauge is arranged on the gas exhaust pipeline.

[0015] Furthermore, under working conditions: the sterilizer tank first performs a heating and temperature-raising stage: the drain valve and the air inlet solenoid valve are closed, the exhaust valve and the water injection solenoid valve are opened, and the flow sensor detects that the water added has reached the set value, then the controller controls the water injection solenoid valve and the exhaust valve to close, and at the same time controls the heating wire to start full-power heating; when the pressure in the sterilizer tank increases to the upper limit value, the controller regulates the exhaust valve to open, while maintaining the high temperature in the sterilizer tank and reducing the pressure in the tank; when the pressure sensor detects that the pressure drops to the set threshold, the exhaust valve is closed again to enter the temperature-raising and pressure-raising process, during which the pressure in the sterilizer tank is controlled within the set range, and the steam temperature rises to the sterilization temperature;

[0016] Sterilization stage: The controller uses PID regulation to control the heating of the heating wire, and at the same time controls the opening and closing of the exhaust valve to control the current pressure between the pressure relief set value and the pressure holding set value, and at the same time controls the temperature within the sterilization temperature range. The sterilization stage ends and the heating wire stops heating;

[0017] During the cooling stage, the water injection solenoid valve starts to spray cooling water. When the pressure value detected by the pressure sensor drops to the set lower limit, the water injection stops. The piston pump and the air inlet solenoid valve are turned on, and the pressure in the sterilizer tank rises again and is kept equal to the pressure in the packaging bag. In this control process, the water injection control is circulated to reduce the temperature in the tank and maintain the pressure balance, finally completing the cooling stage.

[0018] Drainage stage:

[0019] When the cooling water is drained out, the pressure in the sterilizer tank drops to the set value, the air inlet solenoid valve is closed, the piston pump is turned off, and when the pressure drops to 0MPa, the controller controls the drain valve to close and the exhaust valve to open, and the entire sterilization process is completed.

[0020] Due to the adoption of the above technical solution, the present invention provides a food sterilizer control system, which can detect and control the water injection volume to ensure that the water volume in the sterilizer tank is appropriate; at the same time, in the heating stage, the temperature is ensured to rise steadily and the pressure is constant; the installed exhaust valve can ensure that the tank is always within the safe pressure range and increase the service life of the tank; in the sterilization stage, the sterilization temperature is ensured to be accurate through a high-precision temperature control algorithm, and thorough sterilization can be achieved; in the cooling stage, rapid cooling can be ensured and the packaged food can be maintained by spraying cooling water and adding air; the pressure inside and outside the packaging belt is balanced to prevent the packaging bag from bursting; the sterilization method of this sterilizer is to sterilize by high-temperature steam, and the high-temperature steam has no contact with the actual object, which can not only achieve high-temperature sterilization but also avoid bacterial contact contamination, thereby ensuring that the color, flavor, and tissue structure of the food in the package are not damaged, and reducing the corrosion of the packaged food. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a structural block diagram of the food sterilizer control system of the present invention;

[0023] Figure 2 This is a control block diagram of the electrical control part of the food sterilizer of the present invention;

[0024] Figure 3 It is a flow chart of the working process of the food sterilizer control system of the present invention.

[0025] In the figure: 1. Exhaust temperature sensor, 2. Pressure gauge, 3. Pressure sensor, 4. Safety valve, 5. Safety valve assembly, 6. Air intake solenoid valve, 7. Piston pump, 8. Drain valve, 9. Exhaust valve, 10. Sterilizer drain port, 11. Steam temperature sensor, 12. Heating wire, 13. Bottom temperature sensor, 14. Water inlet pipe, 15. Snap-action thermostat, 16. Flow sensor, 17. Water injection solenoid valve, 19. Controller, 21. Heating thyristor, 22. Heating relay, 23. Cooling fan, 100. Gas delivery pipeline, 200. Gas discharge pipeline, 300. Liquid discharge pipeline. DETAILED DESCRIPTION

[0026] To make the technical solutions and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention:

[0027] like Figure 1 and Figure 2 The food sterilizer control system shown in the figure includes an exhaust temperature sensor 1 for measuring the internal temperature of the exhaust pipeline, a pressure sensor 3 for detecting the pressure information inside the sterilizer, the pressure sensor 3 feeds the detected information back to the controller 19 through a 4-20ma signal, a safety valve 4 that automatically opens to exhaust when the pressure in the sterilizer tank is greater than the safety valve limit, a safety valve assembly 5 installed on the sterilizer tank pipeline, an air intake solenoid valve 6 that maintains the pressure balance of the sterilizer tank when the sterilization process is in the cooling stage, a pneumatic piston pump 7 that maintains the pressure balance in the tank when the sterilization process is in the cooling stage, and a drainage control system for the sterilizer tank when the sterilization is completed and enters the drainage stage. Drain valve 8, exhaust valve 9 for balancing the pressure state in the tank when the sterilization stage is the heating stage, sterilizer drain port 10 for draining and exhausting the sterilizer tank, steam temperature sensor 11 for detecting the temperature information of steam in the sterilizer tank during sterilization, heating wire 12 for heating during sterilization, bottom temperature sensor 13 for detecting the temperature around the heating wire, sudden jump thermostat 15 for disconnecting the heating circuit and stopping heating for protection when the tank bottom temperature exceeds the sudden jump thermostat limit when the sterilizer is heated, flow sensor 16 for calculating the amount of water added to the sterilizer tank when starting the sterilization program, water inlet solenoid valve 17 for controlling the opening and closing of water injection in the sterilizer tank.

[0028] Furthermore, the controller 19 is used to receive data information such as temperature and pressure transmitted by the above-mentioned multiple sensors, such as the exhaust temperature sensor 1, the pressure sensor 3, the steam temperature sensor 11, the bottom temperature sensor 13, and the flow sensor 16, and then control the electrical components of the sterilizer according to the detected data information to realize the sterilizer function.

[0029] Furthermore, the function of the heating thyristor 21 is to power the heating wire 12 by high-speed pulse output. When the sterilizer program is started, the heating relay 22 is first started to connect the heating wire circuit.

[0030] Furthermore, during the heating stage, when the pressure inside the sterilizer tank is high, the exhaust valve 9 is opened to reduce the pressure. During the cooling stage, when the pressure inside the sterilizer tank is reduced, the air inlet solenoid valve 6 is opened to increase the pressure. During the cooling stage, the piston pump 7 is opened to increase the pressure inside the tank. Before the sterilization program is started, the water injection solenoid valve 17 is opened to inject water into the tank. When the sterilization program is started, the electronic lock is closed to prevent the tank cover from being opened. During cooling, the cooling fan 23 is turned on to increase the cooling speed.

[0031] like Figure 3 As shown, the sterilizer tank has the following processes in working state:

[0032] 1. Heating stage:

[0033] Close the upper cover, set the parameters, and click Start. The solenoid pops up, the drain valve 8 closes, the air inlet solenoid valve 6 closes, the exhaust valve 9 opens, and the water injection solenoid valve 17 opens. When the flow sensor 16 detects that the added water has reached the set value, for example, 3L (heating water volume), the water injection solenoid valve 17 closes, the exhaust valve 9 closes, and the heating wire 12 starts heating at full power.

[0034] As the heating wire 12 heats, the internal temperature of the sterilizer tank increases, and the pressure within the tank also increases. When the pressure reaches the limit of 0.05 MPa, the exhaust valve 9 opens, reducing the pressure while maintaining the high temperature inside the tank. When the pressure sensor 3 detects that the pressure has dropped to 0.045 MPa, the exhaust valve 9 closes again, and the temperature and pressure increase process continues. This control process ultimately achieves a pressure between 0.045 MPa and 0.05 MPa, while the steam temperature within the tank rises to the sterilization temperature.

[0035] 2. Sterilization stage:

[0036] When the steam temperature reaches the set sterilization temperature, the heating wire 12 is controlled by PID regulation for PWM control; by opening and closing the exhaust valve 9, the pressure is controlled between the pressure relief setting value (saturated water vapor pressure + 0.05MPa) and the pressure holding setting value (0.045MPa), and finally the pressure is stably controlled at (saturated water vapor pressure + 0.045MPa), and the temperature is controlled within the sterilization temperature range. After the sterilization countdown, the sterilization stage ends, the heating wire 12 stops heating, and enters the cooling stage.

[0037] 3. Cooling stage:

[0038] When the sterilizer completes the sterilization process, it enters the cooling stage to lower the temperature inside the tank. After the sterilization stage is completed, the heating wire 12 stops heating, the piston pump 7 is turned on, and then the air inlet solenoid valve 6 is turned on, and the pressure inside the container begins to rise. In order to increase the cooling speed, water is injected into the tank body to achieve rapid cooling. However, while injecting water, the pressure inside the tank will drop rapidly. Since the food is vacuum-packed, the pressure inside the package is maintained at the pressure value before cooling, so there will be a pressure difference, causing the packaging bag to burst. Therefore, before injecting water, the circulation pump is turned on in advance. When the water injection solenoid valve 17 sprays cooling water, the pressure drops sharply. When it drops to the set lower limit, the water injection is stopped. Due to the opening of the circulation pump 7 and the air inlet solenoid valve 6, the pressure inside the tank will rise again and maintain the same pressure inside the package. According to this control process, the water injection control is cyclically carried out to reduce the temperature inside the tank, maintain the pressure balance, and finally complete the cooling stage.

[0039] 4. Drainage stage

[0040] When the cooling water in the container is drained out, the pressure will drop. When the pressure drops to 0.04MPa, the air inlet solenoid valve 6 is closed and the piston pump 7 is closed. When the pressure drops to 0MPa, after a delay of 45 seconds, the drain valve 8 is closed and the exhaust valve 9 is opened, and the entire sterilization process is completed.

[0041] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A working method of a food sterilizer control system, characterized in that: Food sterilizer control system includes: A sensor unit for detecting water injection information, internal water vapor temperature information, and real-time pressure information in the sterilizer tank when in operation; a controller that receives data information transmitted by the sensor unit, and that performs real-time control of the heating, sterilization, cooling, and drainage stages of the sterilizer tank based on the received temperature and pressure information; A valve assembly that receives instruction information transmitted by the controller, wherein the valve assembly controls the opening and closing of a gas discharge pipeline and a liquid discharge pipeline on the sterilizer tank; The sensor unit comprises at least a flow sensor (16) for detecting the amount of water injected into the sterilizer tank, a bottom temperature sensor (13) for detecting the temperature around the heating wire, an exhaust temperature sensor (1) for measuring the internal temperature of the exhaust pipe, a pressure sensor (3) for detecting the internal pressure of the sterilizer tank, and a steam temperature sensor (11) for detecting the temperature of the steam in the tank during the sterilization process. The valve assembly at least comprises a safety valve assembly (5), an air intake solenoid valve (6), a drain valve (8), an exhaust valve (9) and a water injection solenoid valve (17), wherein the safety valve assembly (5) and the air intake solenoid valve (6) are mounted on the gas delivery pipeline on the sterilizer tank, the drain valve (8) is mounted on the liquid discharge pipeline, and the exhaust valve (9) is mounted on the gas discharge pipeline, wherein the liquid discharge pipeline where the drain valve (8) is located is communicated with the gas discharge pipeline where the exhaust valve (9) is located, and a sterilizer drain port (10) is provided at the communicated outlet, and the water injection solenoid valve (17) is mounted on the water inlet pipe of the sterilizer tank; The system also includes a heating wire (12) arranged inside the sterilizer tank to heat it and a piston pump (7) to pressurize the sterilizer tank; The sterilizer tank has the following process in the working state: the sterilizer tank first performs a heating and temperature rising stage: the drain valve (8) and the air inlet solenoid valve (6) are closed, the exhaust valve (9) and the water injection solenoid valve (17) are opened, and the flow sensor (16) detects that the amount of water added has reached the set value, then the controller (19) controls the water injection solenoid valve (17) and the exhaust valve (9) to close, and at the same time controls the heating wire (12) to start full-power heating; when the pressure in the sterilizer tank increases to the upper limit value, the controller (19) controls the exhaust valve (9) to open, and reduces the pressure in the tank while maintaining the high temperature in the sterilizer tank; when the pressure sensor (3) detects that the pressure drops to the set threshold, the exhaust valve (9) is closed again to enter the heating and pressure rising process, during which the steam temperature rises to the sterilization temperature within the set range of the pressure control in the sterilizer tank; Sterilization stage: the controller (19) uses a PID regulation method to control the heating of the heating wire (12), and at the same time controls the opening and closing of the exhaust valve (9) to control the current pressure between the pressure relief set value and the pressure holding set value, and at the same time controls the temperature within the sterilization temperature range, then the sterilization stage ends and the heating wire (12) stops heating; Cooling stage: the water injection solenoid valve (17) starts to spray cooling water. When the pressure value detected by the pressure sensor (3) drops to the set lower limit, the water injection stops. The piston pump (7) and the air inlet solenoid valve (6) are turned on, and the pressure in the sterilizer tank rises again to be consistent with the pressure in the packaging bag. In this control process, the water injection control is circulated to reduce the temperature in the tank and maintain the pressure balance, finally completing the cooling stage. Drainage stage: When the cooling water is drained out, the pressure in the sterilizer tank drops to the set value, the air inlet solenoid valve (6) is closed, the piston pump (7) is closed, and when the pressure drops to 0 MPa, the controller (19) controls the drain valve (8) to close and the exhaust valve (9) to open, and the entire sterilization process is completed.

2. The operating method of a food sterilizer control system according to claim 1, characterized in that: It also includes a heating thyristor (21) and a heating relay (22), wherein the heating thyristor (21) and the heating relay (22) are connected to the heating wire (12), and the controller (19) controls the operation of the heating relay (22) and the heating thyristor (21).

3. The operating method of a food sterilizer control system according to claim 1, characterized in that: It also includes a sudden jump temperature controller (15), which controls the heating wire (12) to stop working when the temperature of the tank bottom exceeds the sudden jump temperature threshold during heating in the sterilizer.

4. The operating method of a food sterilizer control system according to claim 1, characterized in that: It also includes a cooling fan (23), which is connected to the controller (19).

5. The operating method of a food sterilizer control system according to claim 1, characterized in that: It also includes a pressure gauge (2) for displaying pressure information inside the sterilizer tank; the pressure gauge (2) is arranged on the gas exhaust pipeline (200).

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