A control board for a small vacuum packaging machine

Abstract

This utility model discloses a control board for a small vacuum packaging machine. Key technical features include a circuit board on which are mounted: a main control chip powered by a switching power supply circuit; a power drive module whose signal input terminal is electrically connected to the control signal output terminal of the main control chip; and a high-frequency sealing transformer whose primary coil is electrically connected to the drive output terminal of the power drive module, and whose secondary coil is used to connect to the sealing heating strip of the vacuum packaging machine. The power drive module receives the sealing control signal from the main control chip and drives the high-frequency sealing transformer. This utility model, employing a high-frequency sealing transformer and a reasonable circuit module layout, significantly reduces the size and weight of the circuit board, making it suitable for use in small vacuum packaging machines.

Description

Technical Field

[0001] This utility model relates to the field of vacuum packaging machine technology, and more specifically to a control board for a small vacuum packaging machine. Background Technology

[0002] Traditional vacuum packaging machines primarily rely on power frequency (50 / 60Hz) transformers for their sealing function. These transformers convert mains power (220V AC) into low voltage, high current through their core and coils, providing energy to the sealing heating strip. While this technology is structurally simple, the transformer's output power is directly related to the core cross-sectional area and the number of coil turns. To achieve sufficient sealing power, the transformer's size is difficult to reduce, making it unsuitable for miniaturized vacuum packaging machines. Furthermore, the high energy consumption and heat generation of power frequency transformers during prolonged operation can damage other electronic components on the control board, hindering miniaturization of the control board and making it difficult to integrate various functional modules. Utility Model Content

[0003] In view of the shortcomings of the existing technology, the present invention provides a control board for a small vacuum packaging machine, which adopts a high-frequency sealing transformer and a reasonable circuit module layout, greatly reducing the size and weight of the circuit board, making it suitable for use in small vacuum packaging machines.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a control board for a small vacuum packaging machine, comprising a circuit board, wherein the circuit board is provided with:

[0005] The main control chip is powered by a switching power supply circuit mounted on the circuit board.

[0006] The power drive module has its signal input terminal electrically connected to the control signal output terminal of the main control chip;

[0007] The primary coil of the high-frequency sealing transformer is electrically connected to the drive output terminal of the power drive module, and the secondary coil is used to connect to the sealing heating strip of the vacuum packaging machine.

[0008] The power drive module is used to receive the sealing control signal sent by the main control chip and drive the high-frequency sealing transformer to work.

[0009] The present invention is further configured such that the power drive module includes an isolated IGBT power supply module, an isolated IGBT drive circuit, and an IGBT half-bridge drive circuit;

[0010] The input terminal of the isolated IGBT power supply module is electrically connected to the switching power supply circuit, and the output terminal is powered by the isolated IGBT drive circuit.

[0011] The isolated IGBT drive circuit receives the control signal from the main control chip and processes and amplifies the signal to drive the IGBT half-bridge drive circuit.

[0012] The IGBT half-bridge drive circuit receives drive signals from the isolated IGBT drive circuit and drives the high-frequency sealing transformer.

[0013] The present invention is further configured to include a rectifier and filter module, wherein the input end of the rectifier and filter module is used to connect to an external AC power supply, and its output end provides the working voltage for the IGBT half-bridge drive circuit.

[0014] The present invention is further configured to include a protection control module for monitoring the IGBT half-bridge drive circuit. The protection control module obtains the operating current of the IGBT half-bridge drive circuit through a sampling resistor. When the current exceeds a safety threshold, it sends a fault signal to the main control chip so that the main control chip shuts down the drive signal of the IGBT.

[0015] The present invention is further configured to include:

[0016] The display operation control panel is connected to the main control chip and is used for human-computer interaction and sending signals to the main control chip.

[0017] The present invention is further configured such that: the display operation control panel is also connected to:

[0018] Vacuum pump control module, used to connect and control the start and stop of the vacuum pump;

[0019] The sealing valve control module is used to connect to and control the start and stop of the sealing valve;

[0020] The vent valve control module is used to connect to and control the start and stop of the vent valve.

[0021] The present invention is further configured to include an AC input protection module and an EMI filter. The AC input protection module includes at least an overcurrent protection unit. An external AC power supply is connected to a rectifier and filter module after passing through the AC input protection module. The EMI filter is disposed between the rectifier and filter module and the AC input protection module.

[0022] The present invention is further configured such that the input terminal of the rectifier and filter module is connected to the input terminal of the switching power supply circuit.

[0023] In summary, this utility model has the following beneficial effects:

[0024] This invention utilizes a high-frequency sealing transformer in conjunction with an IGBT half-bridge drive circuit to replace the bulky and inefficient power frequency transformer in traditional vacuum packaging machines. This significantly reduces the size and weight of the control board, meeting the requirements of miniaturization. Simultaneously, the energy conversion efficiency of the high-frequency solution is significantly higher than that of the power frequency solution, resulting in faster sealing and heating speeds, thereby significantly improving sealing efficiency and reducing energy consumption.

[0025] Meanwhile, by isolating the IGBT power supply module and the IGBT drive circuit, a safe electrical isolation barrier is established between the main control chip and high-frequency components such as the IGBT half-bridge and high-frequency transformer, which avoids interference to the main control chip and improves the system's anti-interference capability and safety reliability. Attached Figure Description

[0026] Figure 1 This is a block diagram showing the connections of the various circuit modules on the control board.

[0027] Reference numerals in the attached diagram: 1. Main control chip; 2. Power drive module; 3. High-frequency sealing transformer. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to the accompanying drawings.

[0029] like Figure 1 As shown, this embodiment discloses a control board for a small vacuum packaging machine, including a circuit board on which the following are disposed:

[0030] The main control chip is powered by a switching power supply circuit mounted on the circuit board.

[0031] The power drive module has its signal input terminal electrically connected to the control signal output terminal of the main control chip;

[0032] The primary coil of the high-frequency sealing transformer is electrically connected to the drive output terminal of the power drive module, and the secondary coil is used to connect to the sealing heating strip of the vacuum packaging machine.

[0033] The power drive module receives the sealing control signal from the main control chip and drives the high-frequency sealing transformer. Through this structure, the power drive module amplifies the signal from the main control chip to form the subsequent drive signal. Simultaneously, the power drive module electrically isolates the low-voltage control circuit and the high-voltage power circuit to a certain extent, preventing high-voltage interference from damaging the main control chip. Finally, a high-frequency sealing transformer is used, replacing the traditional power frequency transformer. According to electromagnetic principles, the higher the operating frequency of the transformer, the smaller its core cross-sectional area can be, effectively reducing the transformer's size and weight. This achieves miniaturization and portability of the control board, making it suitable for small vacuum packaging machines.

[0034] Furthermore, the power drive module includes an isolated IGBT power supply module, an isolated IGBT drive circuit, and an IGBT half-bridge drive circuit;

[0035] The input terminal of the isolated IGBT power supply module is electrically connected to the switching power supply circuit, and the output terminal is connected to the isolated IGBT drive circuit. The isolated IGBT power supply module provides a stable drive power supply that is electrically isolated from the control system, establishing a safe electrical isolation barrier between the control section and the power section, ensuring the stability and reliability of the system.

[0036] The isolated IGBT driver circuit receives the control signal from the main control chip and processes and amplifies the signal to drive the IGBT half-bridge driver circuit. The isolated IGBT driver circuit receives the control signal from the main control chip and then performs electrical isolation through optocouplers or isolation transformers to achieve electrical isolation transmission of the signal. At the same time, it can provide a sufficiently large drive current so that the IGBT can be turned on and off quickly, significantly reducing the switching loss of the IGBT and preventing it from overheating and burning out due to slow switching.

[0037] The IGBT half-bridge driver circuit receives the drive signal from the isolated IGBT driver circuit and drives the high-frequency sealed transformer. It can be composed of two IGBTs arranged in a half-bridge topology. Under the control of the drive signal, the two IGBTs alternately turn on and off, converting the DC power from the rectified and filtered circuit into a high-frequency AC square wave voltage. Furthermore, compared to full-bridge topologies, the half-bridge structure is relatively simple, cost-effective, and highly efficient in low-to-medium power applications.

[0038] Furthermore, it also includes a rectifier and filter module. The input of the rectifier and filter module is used to connect to an external AC power supply, and its output provides the operating voltage for the IGBT half-bridge drive circuit. The rectifier and filter module outputs a relatively smooth and stable high-voltage DC power, providing the high-voltage DC power supply necessary for the operation of the IGBT half-bridge circuit, which is a prerequisite for replacing the traditional power frequency transformer.

[0039] Furthermore, a protection control module is included to monitor the IGBT half-bridge drive circuit. This module obtains the operating current of the IGBT half-bridge drive circuit through a sampling resistor. When the current exceeds a safety threshold, it sends a fault signal to the main control chip, causing the main control chip to shut down the IGBT drive signal. The specific safety threshold is adaptively selected based on the actual electronic components used. Thus, by continuously monitoring the operating current of the IGBT half-bridge drive circuit through the protection control module, once the current exceeds the safety threshold (i.e., overcurrent or short circuit occurs), the main control chip reacts quickly, ensuring that the IGBT is shut down before it overheats and is damaged due to overcurrent. This prevents the fault from spreading and damaging other parts of the power supply circuit, greatly improving the product's reliability and lifespan.

[0040] Furthermore, this includes a display operation control panel, which connects to the main control chip for human-machine interaction and sends signals to the main control chip. The display panel shows various working statuses, providing intuitive feedback to the user, including but not limited to displaying the current working status (in progress, completed, or faulty), working progress (sealing time, etc.), and parameter settings (setting vacuum time, sealing time, etc.). Simultaneously, the display operation control panel receives user operation commands and sends them to the main control chip, informing the main control chip of the operation the user wants to perform, such as starting sealing.

[0041] Furthermore, the display control panel is also connected to:

[0042] Vacuum pump control module, used to connect and control the start and stop of the vacuum pump;

[0043] The sealing valve control module is used to connect to and control the start and stop of the sealing valve;

[0044] The vent valve control module is used to connect to and control the start and stop of the vent valve.

[0045] Specifically, after pressing the corresponding button on the user control panel, the display control panel sends a signal to the main control chip. The main control chip then sends back the corresponding execution signal, which is relayed to the execution end via the display control panel to achieve start and stop. It is also important to note that the user control panel should include a forced stop button, which allows for direct hardware control of the execution end to stop urgently without going through the main control chip, enhancing safety in case of malfunctions or other necessary conditions.

[0046] Furthermore, the system includes an AC input protection module and an EMI filter. The AC input protection module includes at least an overcurrent protection unit. External AC power is connected to the rectifier and filter module after passing through the AC input protection module. The EMI filter is positioned between the rectifier and filter module and the AC input protection module. With this structure, the overcurrent protection unit can utilize fuses widely used in existing technologies, which can melt and completely cut off the power supply when the current is too high, preventing damage to internal electronic components. The EMI filter's main function is bidirectional filtering of high-frequency electromagnetic interference. On one hand, it prevents high-frequency noise from the power grid (from other devices) from entering the unit and affecting its operation; on the other hand, it prevents high-frequency noise generated internally (such as from the switching power supply and IGBT high-speed switches) from back-polluting the power grid and interfering with other equipment. Meanwhile, the vacuum pump, sealing valve, and venting valve, requiring mains power, draw power directly from the AC input protection module.

[0047] Furthermore, the input terminal of the rectifier and filter module is connected to the input terminal of the switching power supply circuit. Thus, the switching power supply circuit converts the power, after passing through the AC input protection module and EMI filter, into a low-voltage DC power suitable for the low-voltage devices on the control board. This circuit connection method simplifies the circuit structure, provides a reasonable layout, and also contributes to the miniaturization of the overall control board.

[0048] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the design concept of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A control board for a small vacuum packaging machine, comprising a circuit board, characterized in that: The circuit board is provided with: The main control chip is powered by a switching power supply circuit mounted on the circuit board. The power drive module has its signal input terminal electrically connected to the control signal output terminal of the main control chip; The primary coil of the high-frequency sealing transformer is electrically connected to the drive output terminal of the power drive module, and the secondary coil is used to connect to the sealing heating strip of the vacuum packaging machine. The power drive module is used to receive the sealing control signal sent by the main control chip and drive the high-frequency sealing transformer to work.

2. The control board for a small vacuum packaging machine according to claim 1, characterized in that: The power drive module includes an isolated IGBT power supply module, an isolated IGBT drive circuit, and an IGBT half-bridge drive circuit. The input terminal of the isolated IGBT power supply module is electrically connected to the switching power supply circuit, and the output terminal is powered by the isolated IGBT drive circuit. The isolated IGBT drive circuit receives the control signal from the main control chip and processes and amplifies the signal to drive the IGBT half-bridge drive circuit. The IGBT half-bridge drive circuit receives drive signals from the isolated IGBT drive circuit and drives the high-frequency sealing transformer.

3. The control board for a small vacuum packaging machine according to claim 2, characterized in that: It also includes a rectifier and filter module, whose input terminal is used to connect to an external AC power supply, and whose output terminal provides the operating voltage for the IGBT half-bridge drive circuit.

4. The control board for a small vacuum packaging machine according to claim 2, characterized in that: It includes a protection control module for monitoring the IGBT half-bridge drive circuit. The protection control module obtains the operating current of the IGBT half-bridge drive circuit through a sampling resistor. When the current exceeds the safety threshold, it sends a fault signal to the main control chip so that the main control chip shuts down the IGBT drive signal.

5. The control board for a small vacuum packaging machine according to claim 1, characterized in that: It includes a display operation control panel, which is connected to the main control chip and is used for human-computer interaction and sending signals to the main control chip.

6. The control board for a small vacuum packaging machine according to claim 5, characterized in that: The display and operation control panel is also connected to: Vacuum pump control module, used to connect and control the start and stop of the vacuum pump; The sealing valve control module is used to connect to and control the start and stop of the sealing valve; The vent valve control module is used to connect to and control the start and stop of the vent valve.

7. The control board for a small vacuum packaging machine according to claim 1, characterized in that: It includes an AC input protection module and an EMI filter. The AC input protection module includes at least an overcurrent protection unit. An external AC power supply is connected to a rectifier and filter module after passing through the AC input protection module. The EMI filter is located between the rectifier and filter module and the AC input protection module.

8. The control board for a small vacuum packaging machine according to claim 3, characterized in that: The input terminal of the rectifier and filter module is connected to the input terminal of the switching power supply circuit.

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