Switching signal logic and module and high temperature protection system

Abstract

The application relates to a switching signal logic and module and a high-temperature protection system, and relates to the field of circuit and electronic technology. The switching signal logic and module comprises M input circuits and a logic and chip; the output end of each input circuit is connected with the input end of the logic and chip; each input circuit is connected with a high-temperature protection switch and comprises an indicating lamp for indicating the on-off state of the corresponding high-temperature protection switch. The input circuit is configured to light the indicating lamp and output a high-level signal when the high-temperature protection switch is turned on, and to extinguish the indicating lamp and output a low-level signal when the high-temperature protection switch is turned off; the logic and chip is configured to output a high-level control signal when all the input ends receive the high-level signal, and to output a low-level control signal when at least one input end receives the low-level signal. Thus, the state of the corresponding high-temperature protection switch can be directly determined according to the state of the indicating lamp, and the position of the faulty high-temperature protection switch can be quickly identified.

Description

Technical Field

[0001] This utility model relates to the field of circuit electronics technology, and in particular to a switching signal logic and module and a high-temperature protection system. Background Technology

[0002] In industrial machinery, high-temperature protection switches are a common safety device. These switches detect the machine's temperature and cut off power to heating elements when the temperature becomes too high. Currently, multiple high-temperature protection switches are typically connected in series in a circuit; when any one switch trips due to overheating, the entire circuit is disconnected. This simple and direct method of high-temperature protection effectively prevents damage to industrial machinery or safety accidents caused by localized overheating.

[0003] However, once the entire circuit is disconnected, technicians need to check the status of each high-temperature protection switch one by one to determine which area has overheated. This not only reduces the inspection efficiency and recovery speed of industrial equipment, but may also lead to recurring faults going undetected in a timely manner, increasing the operational risks of industrial equipment. Utility Model Content

[0004] Based on the above problems, this utility model provides a switch signal logic module and a high temperature protection system, which can directly determine the corresponding high temperature protection switch status according to the indicator light status, and thus quickly identify the location of the faulty high temperature protection switch.

[0005] The present invention discloses the following technical solutions:

[0006] In a first aspect, this application discloses a switch signal logic AND module, comprising: M input circuits and a logic AND chip, wherein M is an integer greater than or equal to 2;

[0007] Each input circuit is used to connect to a high-temperature protection switch, and the output terminal of each input circuit is connected to the input terminal of the logic AND chip; each input circuit includes an indicator light, which is used to indicate the on / off state of the corresponding high-temperature protection switch;

[0008] The input circuit is configured to: illuminate the indicator light and output a high-level signal to the logic AND chip when the corresponding high-temperature protection switch is turned on; and extinguish the indicator light and output a low-level signal to the logic AND chip when the corresponding high-temperature protection switch is turned off.

[0009] The logic AND chip is configured to output a high-level control signal when all inputs of the logic AND chip receive a high-level signal, and to output a low-level control signal when at least one input of the logic AND chip receives a low-level signal.

[0010] Optionally, it further includes: a first alarm unit; the first alarm unit is connected to an indicator light of each of the input circuits;

[0011] The first alarm unit is configured to trigger an alarm indication when it detects that the indicator light is in an off state.

[0012] Optionally, the logic and chip includes a first-level AND gate structure and a second-level AND gate structure;

[0013] The first-level AND gate structure includes A first AND gates, each of which includes B input terminals, where A and B are both positive integers, and the product of A and B is M. The second-level AND gate structure includes one second AND gate, which includes A input terminals.

[0014] Each first AND gate in the first-level AND gate structure is configured to: output an intermediate high-level control signal to the second AND gate when all B inputs of the first AND gate receive a high-level signal; and output an intermediate low-level control signal to the second AND gate when at least one of the B inputs of the first AND gate receives a low-level signal.

[0015] The second AND gate is configured to output a high-level control signal when all A inputs of the second AND gate receive the intermediate high-level control signal, and to output a low-level control signal when at least one of the A inputs of the second AND gate receives the intermediate low-level control signal.

[0016] Optionally, the switching signal logic AND module includes multiple logic AND chips, which include C first-level logic AND chips and one second-level logic AND chip;

[0017] Each first-level logic AND chip includes D input terminals, where C and D are both positive integers, and the product of C and D is M. The second-level logic AND chip includes C input terminals, and the output terminal of each input circuit is connected to the input terminal of the first-level logic AND chip.

[0018] Each of the first-stage logic and AND chips is configured to: output an intermediate high-level control signal to the second-stage logic and AND chip when all D inputs of the first-stage logic and AND chip receive a high-level signal; and output an intermediate low-level control signal to the second-stage logic and AND chip when at least one of the D inputs of the first-stage logic and AND chip receives a low-level signal.

[0019] The second-stage logic AND chip is configured to: output a high-level control signal when all C inputs of the second-stage logic AND chip receive the intermediate high-level control signal; and output a low-level control signal when at least one of the C inputs of the second-stage logic AND chip receives the intermediate low-level control signal.

[0020] Optionally, the logic AND chip is a 74HC21D logic AND chip.

[0021] Optionally, the circuit connection of each input circuit is as follows:

[0022] The input terminal of the input circuit is connected to the first terminal of the first resistor, the first terminal of the pull-down resistor, and the first terminal of the current-limiting resistor, respectively. The second terminal of the first resistor is connected to the anode of the indicator light. The second terminal of the current-limiting resistor is connected to the first terminal of the filter capacitor and the cathode of the Zener diode, respectively. The first terminal of the filter capacitor is also used to connect to the output terminal of the input circuit. The cathode of the indicator light, the second terminal of the pull-down resistor, the second terminal of the filter capacitor, and the anode of the Zener diode are all grounded.

[0023] Optionally, the input circuit is specifically configured as follows:

[0024] When the corresponding high-temperature protection switch is turned on, the current flowing through the indicator light is limited by the first resistor, so that the indicator light is lit within the corresponding preset current range;

[0025] By using the current-limiting resistor and the Zener diode, the voltage across the filter capacitor is limited, and the input voltage is converted into an input voltage corresponding to the logic AND chip.

[0026] The input signal is filtered by the current-limiting resistor and the filter capacitor, and a high-level signal after step-down filtering is output to the logic AND chip.

[0027] Optionally, it also includes: a relay;

[0028] The input terminal of the relay is connected to the output terminal of the logic AND chip, and the output terminal of the relay is connected to the heater power supply circuit.

[0029] The relay is configured to: control the heater power supply circuit to conduct when the high-level control signal is received; and control the heater power supply circuit to cut off when the low-level control signal is received.

[0030] Optionally, it further includes: a second alarm unit; the second alarm unit is connected to the output terminal of the logic AND chip;

[0031] The second alarm unit is configured to trigger an alarm indication when the low-level control signal is received.

[0032] Secondly, this application discloses a high-temperature protection system, comprising: M high-temperature protection switches and a switch signal logic AND module as described in the first aspect, wherein the M high-temperature protection switches are respectively connected to the M input circuits of the switch signal logic AND module.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] This utility model discloses a switch signal logic AND module and a high-temperature protection system, comprising: M input circuits and an AND chip, where M is an integer greater than or equal to 2; each input circuit is used to connect to a high-temperature protection switch, and the output terminal of each input circuit is connected to the input terminal of the AND chip; each input circuit includes an indicator light, which indicates the on / off state of the corresponding high-temperature protection switch; the input circuit is configured to: illuminate the indicator light and output a high-level signal to the AND chip when the corresponding high-temperature protection switch is on; extinguish the indicator light and output a low-level signal to the AND chip when the corresponding high-temperature protection switch is off; the AND chip is configured to: output a high-level control signal when all input terminals of the AND chip receive a high-level signal; and output a low-level control signal when at least one input terminal of the AND chip receives a low-level signal. Therefore, through the independently configured indicator light of each input circuit, the on / off state of the corresponding high-temperature protection switch can be intuitively displayed. When any high-temperature protection switch is abnormally disconnected, the fault point can be accurately located immediately through the extinguished indicator light, significantly improving troubleshooting efficiency. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 A schematic diagram of a switch signal logic and module provided by this utility model;

[0037] Figure 2 A schematic diagram of an input circuit provided by this utility model;

[0038] Figure 3 A schematic diagram of another input circuit provided by this utility model;

[0039] Figure 4A schematic diagram of a logic chip provided by this utility model;

[0040] Figure 5 A schematic diagram of another logic and chip provided by this utility model;

[0041] Figure 6 A schematic diagram of a 74HC21D logic chip provided for this utility model;

[0042] Figure 7 A schematic diagram of another switching signal logic and module provided by this utility model;

[0043] Figure 8 This is a schematic diagram of a switch signal logic and module provided in an embodiment of this application. Detailed Implementation

[0044] In industrial machinery, high-temperature protection switches are a common safety device. These switches detect the machine's temperature and cut off power to heating elements when the temperature becomes too high. Currently, multiple high-temperature protection switches are typically connected in series in a circuit; when any one switch trips due to overheating, the entire circuit is disconnected. This simple and direct method of high-temperature protection effectively prevents damage to industrial machinery or safety accidents caused by localized overheating.

[0045] However, once the entire circuit is disconnected, technicians need to check the status of each high-temperature protection switch one by one to determine which area has overheated. This not only reduces the inspection efficiency and recovery speed of industrial equipment, but may also lead to recurring faults going undetected in a timely manner, increasing the operational risks of industrial equipment.

[0046] In view of this, the present invention discloses a switch signal logic AND module and a high-temperature protection system, comprising: M input circuits and an AND chip, wherein M is an integer greater than or equal to 2; each input circuit is used to connect to a high-temperature protection switch, and the output terminal of each input circuit is connected to the input terminal of the AND chip; each input circuit includes an indicator light, which is used to indicate the on / off state of the corresponding high-temperature protection switch; the input circuit is configured to: illuminate the indicator light and output a high-level signal to the AND chip when the corresponding high-temperature protection switch is on; extinguish the indicator light and output a low-level signal to the AND chip when the corresponding high-temperature protection switch is off; the AND chip is configured to: output a high-level control signal when all input terminals of the AND chip receive a high-level signal; and output a low-level control signal when at least one input terminal of the AND chip receives a low-level signal. Thus, through the independently configured indicator light of each input circuit, the on / off state of the corresponding high-temperature protection switch can be intuitively displayed. When any high-temperature protection switch is abnormally disconnected, the fault point can be accurately located immediately through the extinguished indicator light, significantly improving troubleshooting efficiency.

[0047] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] See Figure 1 This figure is a schematic diagram of a switch signal logic and module provided by this utility model. Figure 1 As shown, the switch signal logic AND module includes M input circuits and an AND chip, where M is an integer greater than or equal to 2.

[0049] Each input circuit connects to a high-temperature protection switch (such as a thermal switch). The output of each input circuit connects to the input of a logic AND chip. Each input circuit includes an indicator light (such as an LED) to indicate the on / off state of the corresponding high-temperature protection switch.

[0050] Specifically, the input circuit is configured to: illuminate the indicator light (indicating normal temperature) and output a high-level signal to the logic and AND chip when the corresponding high-temperature protection switch is turned on; and extinguish the indicator light (warning of potential overheating risk) and output a low-level signal to the logic and AND chip when the corresponding high-temperature protection switch is turned off.

[0051] The AND chip is configured such that when all inputs receive a high-level signal, all high-temperature protection switches are on, and the AND chip outputs a high-level control signal to allow power to the heater. When at least one input receives a low-level signal, at least one high-temperature protection switch is off, and the AND chip outputs a low-level control signal to immediately cut off the heater power supply, preventing potential safety hazards.

[0052] Understandably, in actual deployment, different methods can be chosen to distinguish the status of the high-temperature protection switch as needed. Besides the aforementioned "indicator light on - indicator light off" method, different colored indicator lights (e.g., green for conduction, red for cutoff) can also be used to reflect status changes. This application does not limit this approach.

[0053] Next, we will introduce the input circuit of the switch signal logic module:

[0054] See Figure 2 This figure is a schematic diagram of an input circuit provided in an embodiment of this application. Figure 2 As shown, each of the input circuits adopts a two-stage processing architecture of voltage regulation and filtering, and the specific connection relationship is as follows:

[0055] The input terminal EX_IN1 of the input circuit is used to connect an external high-temperature protection switch and receives a 12-24V DC input. The input terminal EX_IN1 is connected to the first terminal of the first resistor R160, the first terminal of the pull-down resistor R49, and the first terminal of the current-limiting resistor R161. The second terminal of the first resistor R160 is connected to the anode of the indicator LED39. The second terminal of the current-limiting resistor R161 is connected to the first terminal of the filter capacitor C44 and the cathode of the Zener diode D42. The Zener diode D42 limits the voltage applied to the filter capacitor C44 to prevent excessive voltage from damaging the logic chips connected later. The first terminal of the filter capacitor C44 is also used to connect to the output terminal IN1 of the input circuit. The cathode of the indicator LED39, the second terminal of the pull-down resistor R49, the second terminal of the filter capacitor C44, and the anode of the Zener diode D42 are all grounded.

[0056] Indicator LED39 is a light-emitting diode (LED) used to visually display the status of the corresponding high-temperature protection switch. When the high-temperature protection switch is on, indicator LED39 will light up; when the high-temperature protection switch is off, indicator LED39 will turn off, indicating a possible fault or overheating.

[0057] Specifically, when the corresponding high-temperature protection switch is turned on, the input voltage limits the current flowing through indicator LED39 via the first resistor R160, ensuring that LED39 is lit within the preset current range, indicating that the high-temperature protection switch is in the on state. Furthermore, the voltage regulation circuit composed of current-limiting resistor R161 and Zener diode D42 limits the voltage across filter capacitor C44, converting the input voltage into the input voltage corresponding to the logic AND chip. Additionally, the RC filter circuit composed of current-limiting resistor R161 and filter capacitor C44 filters the input signal, ultimately outputting a stepped-down filtered high-level signal to the logic AND chip, indicating that the corresponding part of the input circuit is working normally.

[0058] When the corresponding high-temperature protection switch is turned off, indicator LED39 goes out, indicating that the high-temperature protection switch has been turned off. The input circuit no longer outputs a high-level signal to the logic AND chip, but instead outputs a low-level signal.

[0059] It is understood that this application does not limit the specific resistance and capacitance values.

[0060] See Figure 3 The figure is a schematic diagram of another input circuit provided by this utility model. Figure 3 Taking a circuit with four inputs as an example, each input circuit employs a two-stage processing architecture of voltage regulation and filtering.

[0061] Next, we will introduce the logic and chip of the switching signal logic and module:

[0062] In one specific implementation, see Figure 4 This figure is a schematic diagram of a logic chip provided by this utility model. Figure 4 As shown, the logic chip includes a first-level AND gate structure and a second-level AND gate structure. The first-level AND gate structure includes A first-level AND gates, each with B input terminals, where A and B are both positive integers, and their product is the number of input circuits, M. The second-level AND gate structure includes one second-level AND gate, which has A input terminals.

[0063] Understandable Figure 4 The example uses A=3, B=4, and M=12 for illustration. This application does not limit the specific values.

[0064] Specifically, each first AND gate in the first-level AND gate structure is configured to: when all B inputs of the first AND gate receive a high-level signal, output an intermediate high-level control signal (high-level signal) to the second AND gate; when at least one of the B inputs of the first AND gate receives a low-level signal, output an intermediate low-level control signal (low-level signal) to the second AND gate. For example, as shown... Figure 3 As shown, each first AND gate processes 4 input signals (B=4). The first AND gate will output a middle high-level control signal only when all 4 input signals are high; otherwise, the first AND gate will output a middle low-level control signal as long as one input signal is low.

[0065] The second AND gate is configured to: when all A inputs of the second AND gate receive a mid-level high-level control signal, output a high-level control signal (high-level signal), allowing power to the heater. When at least one of the A inputs of the second AND gate receives a mid-level low-level control signal, output a low-level control signal (low-level signal), immediately cutting off the heater power. For example, as shown... Figure 3 As shown, the second AND gate receives control signals from three first AND gates (A=3). The second AND gate will output a high-level control signal only when all three control signals are high; otherwise, the second AND gate will output a low-level control signal as long as one control signal is low.

[0066] In another specific implementation, see Figure 5 This figure is a schematic diagram of another logic and chip provided by this utility model. Figure 5 As shown, the switching signal logic AND module can also include multiple logic AND chips, specifically C first-level logic AND chips and one second-level logic AND chip. The output of each input circuit is connected to the input of one of the first-level logic AND chips. Each first-level logic AND chip includes D inputs, where C and D are both positive integers, and the product of C and D is the number of input circuits, M. The second-level logic AND chip includes C inputs.

[0067] Understandable Figure 5 The example uses C=3, D=4, and M=12 for illustration. This application does not limit the specific values.

[0068] Each first-stage logic AND chip is configured to: when all D inputs of the first-stage logic AND chip receive a high-level signal, output an intermediate high-level control signal (high-level signal) to the second-stage logic AND chip; and when at least one of the D inputs of the first-stage logic AND chip receives a low-level signal, output an intermediate low-level control signal (low-level signal) to the second-stage logic AND chip.

[0069] The second-stage logic AND chip is configured to: when all C inputs of the second-stage logic AND chip receive a mid-level high-level conduction control signal, output a high-level control signal (high-level signal) to enable power supply to the heater. When at least one of the C inputs of the second-stage logic AND chip receives a mid-level low-level control signal, output a low-level control signal (low-level signal) to immediately cut off the heater power supply.

[0070] See Figure 6 This figure is a schematic diagram of a 74HC21D logic AND chip provided in an embodiment of this application. In the switch signal logic AND module provided in this embodiment, the logic AND chip can be a 74HC21D logic AND chip.

[0071] In one specific implementation, in order to further enhance the reliability and security of the switching signal logic and module, in addition to the indicator lights configured independently for each input circuit, a first alarm unit and a second alarm unit can also be set.

[0072] Specifically, the first alarm unit is connected to the indicator light of each input circuit. Its main function is to immediately trigger an alarm indication when any indicator light is detected to be off (i.e., the corresponding high-temperature protection switch is open). The second alarm unit is connected to the output of the logic AND chip. Its main function is to trigger an alarm indication when a low-level control signal is received (i.e., the high-temperature protection switch is open).

[0073] Understandably, alarm indications can be provided by flashing warning lights or color changes (such as from green to red) to alert relevant technical personnel. Alternatively, alarms can be triggered by buzzers or other sound devices to alert relevant technical personnel. In the future, alarm information can be sent to a remote monitoring center or the mobile devices of relevant technical personnel via the network to ensure that they receive alarms in a timely manner even when they are not on-site.

[0074] Therefore, in addition to the indicator lights configured independently for each input circuit, the switch signal logic and module can quickly issue an alarm when the high temperature protection switch is disconnected through the dual monitoring of the first alarm unit and the second alarm unit, ensuring that timely measures are taken to prevent the fault from escalating or causing more serious consequences.

[0075] See Figure 7 The figure is a schematic diagram of another switching signal logic and module provided by this utility model. Figure 7 The switching signal logic and module in Figure 1Compared to the previous module, this new module incorporates a relay to control the heater power supply circuit. The relay's input is connected to the logic chip's output, and its output is connected to the heater power supply circuit. The relay is configured to: turn on the heater power supply circuit when a high-level control signal is received; and turn off the heater power supply circuit when a low-level control signal is received.

[0076] Understandably, relays, as electrical isolation devices, can provide physical isolation between control signals (including high-level and low-level control signals) and the heater, preventing high-voltage side faults from affecting the low-voltage side heater power supply circuit, and ensuring the safety and reliability of the switching signal logic and modules.

[0077] Specifically, see Figure 8 This figure is a schematic diagram of a switch signal logic and module provided in an embodiment of this application. Figure 8 As shown, when the final output pin of the logic AND chip outputs a high level, resistor R40 limits the current, ensuring that the current flowing through the base of transistor Q1 is within the operating range, allowing transistor Q1 to fully turn on, with its collector and emitter conducting. At this time, the current from power supply VCC splits into two paths: one path flows through resistor R35, indicator LED9, and transistor Q1 to ground, lighting LED9 to indicate the heater's operating status; the other path flows through the relay drive coil and transistor Q1 to ground, closing the relay contacts, connecting the heater's power supply circuit, and starting the heater to operate.

[0078] When the final output pin of the logic AND chip goes low, resistor R41 pulls the base voltage of transistor Q1 down to 0V, completely turning off transistor Q1. At this time, the circuit from power supply VCC to ground is cut off, indicator light LED9 goes out, the relay drive coil is de-energized, the contacts open, the heater power supply circuit is cut off, and the heater stops working. In addition, diode D10 is connected in reverse parallel across the relay drive coil to provide a freewheeling path when the relay is turned off, absorb the reverse electromotive force generated by the coil, and protect other components in the circuit from high-voltage surges.

[0079] It is understood that through the above design, this utility model achieves reliable control of the heater power supply circuit, while also having status indication and electrical isolation functions, further improving safety and stability.

[0080] In summary, this utility model discloses a switch signal logic AND module, comprising: M input circuits and an AND chip, where M is an integer greater than or equal to 2; each input circuit is used to connect to a high-temperature protection switch, and the output terminal of each input circuit is connected to the input terminal of the AND chip; each input circuit includes an indicator light, which indicates the on / off state of the corresponding high-temperature protection switch; the input circuit is configured to: illuminate the indicator light and output a high-level signal to the AND chip when the corresponding high-temperature protection switch is on; extinguish the indicator light and output a low-level signal to the AND chip when the corresponding high-temperature protection switch is off; the AND chip is configured to: output a high-level control signal when all input terminals of the AND chip receive a high-level signal; and output a low-level control signal when at least one input terminal of the AND chip receives a low-level signal. Therefore, through the independently configured indicator light of each input circuit, the on / off state of the corresponding high-temperature protection switch can be intuitively displayed. When any high-temperature protection switch is abnormally disconnected, the fault point can be accurately located immediately through the extinguished indicator light, significantly improving troubleshooting efficiency.

[0081] This application also discloses a high-temperature protection system, comprising: M high-temperature protection switches and a switch signal logic AND module as described in the first aspect, wherein the M high-temperature protection switches are respectively connected to the M input circuits of the switch signal logic AND module.

[0082] The high-temperature protection system disclosed in this application has the same beneficial effects as the switching signal logic and module disclosed in this application.

[0083] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0084] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A switching signal logic and module, characterized by, include: M input circuits and logic AND chips, where M is an integer greater than or equal to 2; Each input circuit is used to connect to a high-temperature protection switch, and the output terminal of each input circuit is connected to the input terminal of the logic AND chip; each input circuit includes an indicator light, which is used to indicate the on / off state of the corresponding high-temperature protection switch; The input circuit is configured to: illuminate the indicator light and output a high-level signal to the logic AND chip when the corresponding high-temperature protection switch is turned on; and extinguish the indicator light and output a low-level signal to the logic AND chip when the corresponding high-temperature protection switch is turned off. The logic AND chip is configured to output a high-level control signal when all inputs of the logic AND chip receive a high-level signal, and to output a low-level control signal when at least one input of the logic AND chip receives a low-level signal.

2. The switch signal logic and module of claim 1, wherein, Also includes: First alarm unit; The first alarm unit is connected to an indicator light of each of the input circuits; The first alarm unit is configured to trigger an alarm indication when it detects that the indicator light is in an off state.

3. The switch signal logic and module of claim 1, wherein, The logic and chip include a first-level AND gate structure and a second-level AND gate structure; The first-level AND gate structure includes A first AND gates, each of which includes B input terminals, where A and B are both positive integers, and the product of A and B is M. The second-level AND gate structure includes one second AND gate, which includes A input terminals. Each first AND gate in the first-level AND gate structure is configured to: output an intermediate high-level control signal to the second AND gate when all B inputs of the first AND gate receive a high-level signal; and output an intermediate low-level control signal to the second AND gate when at least one of the B inputs of the first AND gate receives a low-level signal. The second AND gate is configured to output a high-level control signal when all A inputs of the second AND gate receive the intermediate high-level control signal, and to output a low-level control signal when at least one of the A inputs of the second AND gate receives the intermediate low-level control signal.

4. The switching signal logic and module of claim 1, wherein, The switching signal logic AND module includes multiple logic AND chips, which include C first-level logic AND chips and one second-level logic AND chip. Each first-level logic AND chip includes D input terminals, where C and D are both positive integers, and the product of C and D is M. The second-level logic AND chip includes C input terminals, and the output terminal of each input circuit is connected to the input terminal of the first-level logic AND chip. Each of the first-stage logic and AND chips is configured to: output an intermediate high-level control signal to the second-stage logic and AND chip when all D inputs of the first-stage logic and AND chip receive a high-level signal; and output an intermediate low-level control signal to the second-stage logic and AND chip when at least one of the D inputs of the first-stage logic and AND chip receives a low-level signal. The second-stage logic AND chip is configured to: output a high-level control signal when all C inputs of the second-stage logic AND chip receive the intermediate high-level control signal; and output a low-level control signal when at least one of the C inputs of the second-stage logic AND chip receives the intermediate low-level control signal.

5. The switching signal logic and module of claim 1, wherein, The logic and AND chip is a 74HC21D logic and AND chip.

6. The switching signal logic and module of claim 1, wherein, The circuit connection of each of the input circuits is as follows: The input terminal of the input circuit is connected to the first terminal of the first resistor, the first terminal of the pull-down resistor, and the first terminal of the current-limiting resistor, respectively. The second terminal of the first resistor is connected to the anode of the indicator light. The second terminal of the current-limiting resistor is connected to the first terminal of the filter capacitor and the cathode of the Zener diode, respectively. The first terminal of the filter capacitor is also used to connect to the output terminal of the input circuit. The cathode of the indicator light, the second terminal of the pull-down resistor, the second terminal of the filter capacitor, and the anode of the Zener diode are all grounded.

7. The switch signal logic and module of claim 6, wherein, The input circuit is specifically configured as follows: When the corresponding high-temperature protection switch is turned on, the current flowing through the indicator light is limited by the first resistor, so that the indicator light is lit within the corresponding preset current range; By using the current-limiting resistor and the Zener diode, the voltage across the filter capacitor is limited, and the input voltage is converted into an input voltage corresponding to the logic AND chip. The input signal is filtered by the current-limiting resistor and the filter capacitor, and a high-level signal after step-down filtering is output to the logic AND chip.

8. The switching signal logic and module of claim 1, wherein, Also includes: Relay; The input terminal of the relay is connected to the output terminal of the logic AND chip, and the output terminal of the relay is connected to the heater power supply circuit. The relay is configured to: control the heater power supply circuit to conduct when the high-level control signal is received; and control the heater power supply circuit to cut off when the low-level control signal is received.

9. A switching signal logic and module according to any of claims 1-8, characterized in that, Also includes: The second alarm unit is connected to the output terminal of the logic and AND chip. The second alarm unit is configured to trigger an alarm indication when the low-level control signal is received.

10. A high temperature protection system, characterized in that include: M high-temperature protection switches and a switch signal logic AND module as described in any one of claims 1-9, wherein the M high-temperature protection switches are respectively connected to the M input circuits of the switch signal logic AND module.

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