A load short circuit protection circuit and a noodle making machine device

Abstract

The application relates to the technical field of electronic circuits, and discloses a load short-circuit protection circuit and a noodle pressing machine device, which comprise a driving control module and a protection control module. The protection control module controls the driving control module to be controlled by a second target signal sent by a controller according to a first target signal received by the controller, so as to drive a load. The protection control module generates a protection trigger signal according to an electrical signal of the load. When the protection trigger signal is used to indicate that the load is short-circuited, the protection control module is turned on and the driving control module is turned off according to the protection trigger signal. It can be seen that the load short-circuit protection efficiency and accuracy can be improved by implementing the application.

Description

Technical Field

[0001] This invention relates to the field of electronic circuit technology, and in particular to a load short-circuit protection circuit and a noodle pressing machine. Background Technology

[0002] In the motor drive circuits of small household appliances (such as pasta makers and juicers), the motor is the core load, and the reliability of its drive circuit is crucial. Especially during production assembly or user use, the load (motor) leads may short-circuit unexpectedly. Such a short circuit will generate a large current far exceeding the rated value. If the power supply is not cut off in time, it can easily burn out the core switching devices (such as MOSFETs) in the circuit within a very short time, leading to product failure or even a safety accident.

[0003] In existing technologies, short-circuit protection solutions primarily monitor the load current in real time using a current sampling resistor and sample it via an analog-to-digital converter (ADC) of a microcontroller (MCU). When the MCU program determines that the current value exceeds a preset threshold, the MCU outputs a signal to actively shut down the drive transistor. However, this solution has inherent drawbacks: First, its response speed is limited by the software sampling period and program execution time, typically in the millisecond (ms) range. For instantaneous large currents that can cause damage within microseconds (μs), protection is often untimely, resulting in a protection blind zone. Second, the current sampling signal is susceptible to electromagnetic noise interference, which may lead to MCU misjudgment, causing false protection of the system and affecting normal operation.

[0004] Therefore, it is particularly important to propose a technical solution to improve the efficiency and accuracy of load short-circuit protection. Summary of the Invention

[0005] This invention provides a load short-circuit protection circuit and a dough press machine, which can improve the efficiency and accuracy of load short-circuit protection.

[0006] To address the aforementioned technical problems, the first aspect of this invention discloses a load short-circuit protection circuit, the circuit comprising a drive control module and a protection control module, wherein: The first terminal of the drive control module is electrically connected to the first terminal of the protection control module, the second terminal of the drive control module and the second terminal of the protection control module are used to electrically connect to the load, and the third terminal of the drive control module and the third terminal of the protection control module are used to electrically connect to the controller. The protection control module is used to control the drive control module to be controlled by the second target signal sent by the controller, based on the first target signal received from the controller, so as to drive the load; The protection control module is further configured to generate a protection trigger signal based on the detected electrical signal of the load; when the protection trigger signal indicates that the load is short-circuited, the protection control module is turned on and the drive control module is turned off based on the protection trigger signal.

[0007] As an optional implementation, in the first aspect of the present invention, the protection control module includes a short-circuit control module and a detection and analysis module, wherein: The first terminal of the short-circuit control module is electrically connected to the first terminal of the detection and analysis module, the second terminal of the short-circuit control module is electrically connected to the first terminal of the drive control module, the third terminal of the short-circuit control module is used to electrically connect to the controller, and the second terminal of the detection and analysis module is electrically connected to the second terminal of the drive control module and is also used to electrically connect to the load. The short-circuit control module is used to control the drive control module to be controlled by the second target signal sent by the controller, based on the first target signal received from the controller, so as to drive the load; The detection and analysis module is used to generate a protection trigger signal based on the detected electrical signal of the load; and to determine whether the protection trigger signal is used to indicate that the load is short-circuited. The short-circuit control module is further configured to, when the detection and analysis module determines that the protection trigger signal indicates that the load is short-circuited, turn on the protection control module and turn off the drive control module according to the protection trigger signal.

[0008] As an optional implementation, in the first aspect of the present invention, the drive control module includes a switch control module and a drive protection module, wherein: The first terminal of the switch control module is electrically connected to the first terminal of the drive protection module, the second terminal of the switch control module is electrically connected to the second terminal of the protection control module and is used to electrically connect to the load, the second terminal of the drive protection module is electrically connected to the first terminal of the protection control module, and the third terminal of the drive protection module is used to electrically connect to the controller. The drive protection module is configured to, in response to the second target signal, turn on the switch control module to drive the load; and, in response to the protection trigger signal, turn off the switch control module.

[0009] As an optional implementation, in the first aspect of the present invention, the short-circuit control module includes a switching transistor Q8 and a current-limiting resistor R38; the detection and analysis module includes a voltage divider resistor R34 and a voltage divider resistor R37, wherein: The first terminal of the switching transistor Q8 is electrically connected to one end of the voltage divider resistor R34, one end of the voltage divider resistor R37, and one end of the current limiting resistor R38. The second terminal of the switching transistor Q8 is electrically connected to the other end of the voltage divider resistor R37 and is used for grounding. The third terminal of the switching transistor Q8 is electrically connected to the first terminal of the drive control module. The other end of the voltage divider resistor R34 is electrically connected to the second terminal of the drive control module and is used for electrical connection to the load. The other end of the current limiting resistor R38 is used for electrical connection to the controller.

[0010] As an optional implementation, in the first aspect of the present invention, the switch control module includes a switch transistor Q7; the drive protection module includes a drive pull-up resistor R32, a drive and current-limiting resistor R33, and a gate pull-down resistor R35, wherein: The first terminal of the switching transistor Q7 is electrically connected to one end of the gate pull-down resistor R35 and one end of the drive and current limiting resistor R33. The second terminal of the switching transistor Q7 is electrically connected to the second terminal of the protection control module and is used to electrically connect to the load. The third terminal of the switching transistor Q7 and the other end of the gate pull-down resistor R35 are used to ground. The other end of the drive and current limiting resistor R33 is electrically connected to the first terminal of the protection control module and one end of the drive pull-up resistor R32. The other end of the drive pull-up resistor R32 is used to electrically connect to the controller.

[0011] As an optional implementation, in the first aspect of the present invention, the circuit further includes a data acquisition and feedback module, wherein: The first terminal of the acquisition and feedback module is electrically connected to the fourth terminal of the drive control module and the fourth terminal of the protection control module, and the second terminal of the acquisition and feedback module is used to electrically connect to the controller; The acquisition and feedback module is used to sample the current flowing through the load and generate a corresponding current feedback signal to feed back to the controller.

[0012] As an optional implementation, in the first aspect of the present invention, the acquisition feedback module includes a sampling resistor R39, a bias resistor R36, and a filter capacitor C12, wherein: One end of the sampling resistor R39 is electrically connected to one end of the bias resistor R36 and the fourth terminal of the drive control module. The other end of the sampling resistor R39 is electrically connected to the fourth terminal of the protection control module and is used for grounding. The other end of the bias resistor R36 is electrically connected to one end of the filter capacitor C12 and is used for electrical connection to the controller. The other end of the filter capacitor C12 is used for grounding.

[0013] As an optional implementation, in the first aspect of the present invention, the circuit further includes a power input and filtering module, wherein: The first terminal of the power input and filtering module is electrically connected to the second terminal of the drive control module and the second terminal of the protection control module. The second terminal of the power input and filtering module is used to electrically connect to the load. The third terminal of the power input and filtering module is used to electrically connect to the power supply. The power input and filtering module is used to receive the external power supply, and after performing reverse connection protection and filtering on the power supply, it supplies power to the circuit.

[0014] As an optional implementation, in the first aspect of the present invention, the power input and filtering module includes a reverse connection protection diode D3 and a filtering / decoupling capacitor C5, wherein: One end of the reverse polarity protection diode D3 is electrically connected to one end of the filter / decoupling capacitor C5, the second end of the drive control module, and the second end of the protection control module, and is used to electrically connect to the negative potential end of the load. The other end of the reverse polarity protection diode D3 is electrically connected to the other end of the filter / decoupling capacitor C5, and is used to electrically connect to the positive potential end of the power supply and the load.

[0015] The second aspect of the present invention discloses a dough pressing machine, which includes the load short-circuit protection circuit described in the first aspect of the present invention.

[0016] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: In this embodiment of the invention, the load short-circuit protection circuit includes a drive control module and a protection control module. The protection control module controls the drive control module to be controlled by a second target signal sent by the controller, so as to drive the load, according to the first target signal received from the controller. The protection control module generates a protection trigger signal according to the detected electrical signal of the load. When the protection trigger signal is used to indicate a load short circuit, the protection control module is turned on and the drive control module is turned off according to the protection trigger signal. As can be seen, implementing this invention enables the protection control module to receive the first target signal as a primary controller to initialize the circuit, thereby improving the controllability and stability of the load short-circuit protection circuit. This helps ensure that the hardware protection logic of the load short-circuit protection circuit is in a non-intervention state before the load drive starts, preventing malfunctions, improving the accuracy of load short-circuit protection, and enhancing the startup safety of subsequent hardware-based load short-circuit protection logic. After the protection control module controls the drive control module as a secondary controller, controlled by the second target signal sent by the controller, to drive the load based on the first target signal, the protection control module can determine whether the load is short-circuited based on the detected electrical signal of the load, without any intervention from the controller software program. At the instant the load short circuit occurs, the protection control module is turned on and the drive control module is turned off according to the protection trigger signal. This ensures that the load short-circuit protection action is completed by the interlocking relationship between the drive control module and the protection control module at the instant the load short circuit occurs, improving the efficiency of load short-circuit protection, timely cutting off the fault current, and preventing damage to sensitive power switching devices due to instantaneous large currents. This, in turn, helps improve the safety and lifespan of the entire drive circuit, achieving fast and self-consistent hardware-level safety protection. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a load short-circuit protection circuit disclosed in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a protection control module disclosed in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a drive control module disclosed in an embodiment of the present invention; Figure 4 This is a schematic diagram of another load short-circuit protection circuit disclosed in an embodiment of the present invention. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0020] It should be noted that, unless otherwise explicitly specified and limited, the term "electrical connection" in the specification, claims, and accompanying drawings of this invention should be interpreted broadly. For example, it can refer to a fixed electrical connection, a detachable electrical connection, or an integral electrical connection; it can be a mechanical electrical connection, an electrical-electrical connection, or a connection capable of communication; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection of two elements or the interaction between two elements. Furthermore, the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order. The terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0021] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] This invention discloses a load short-circuit protection circuit and a dough press machine. The circuit can receive a first target signal as a primary controller to initialize the circuit, improving the controllability and stability of the load short-circuit protection circuit's startup. This helps ensure that the hardware protection logic of the load short-circuit protection circuit is in a non-intervention state before the load is driven to start, preventing malfunctions, improving the accuracy of load short-circuit protection, and enhancing the startup security of subsequent hardware-based load short-circuit protection logic. After the protection control module controls the drive control module as a secondary controller, controlled by a second target signal sent by the controller, to drive the load, it can... The protection control module determines whether the load is short-circuited based on the detected electrical signal of the load, without any intervention from the controller software. At the instant a short circuit occurs, the protection control module is activated and the drive control module is deactivated by a protection trigger signal. This ensures that the load short-circuit protection action is completed instantly through the interlocking relationship between the drive control module and the protection control module, improving the efficiency of load short-circuit protection, promptly cutting off fault current, and preventing damage to sensitive power switching devices due to instantaneous high current. This, in turn, enhances the safety and lifespan of the entire drive circuit, achieving fast and self-consistent hardware-level safety protection. Detailed explanations follow.

[0023] Example 1 Please see Figure 1 , Figure 1 This is a schematic diagram of a load short-circuit protection circuit disclosed in an embodiment of the present invention. Figure 1 The described load short-circuit protection circuit can be applied to small household appliances such as noodle presses and juicers, and also to smart devices associated with these appliances. These smart devices include, but are not limited to, one or more of the following: smart home devices, switching devices, cloud devices, edge computing devices, relay devices, base station devices, urban management devices, and smart connected devices. This invention is not limited in its embodiments. Figure 1 As shown, the load short-circuit protection circuit may include a drive control module 10 and a protection control module 20, wherein: The first end of the drive control module 10 is electrically connected to the first end of the protection control module 20, the second end of the drive control module 10 and the second end of the protection control module 20 are used to electrically connect to the load, and the third end of the drive control module 10 and the third end of the protection control module 20 are used to electrically connect to the controller. The protection control module 20 is used to control the drive control module 10 to drive the load by being controlled by the second target signal sent by the controller, based on the first target signal received from the controller. The protection control module 20 is also used to generate a protection trigger signal based on the detected electrical signal of the load; when the protection trigger signal is used to indicate a load short circuit, the protection control module 20 is turned on and the drive control module 10 is turned off according to the protection trigger signal.

[0024] It should be noted that the first end, second end, etc. described in the embodiments of the present invention are not limited to having only one electrically connected lead in actual applications. They may contain one or more leads. For the sake of simplification, the connection relationship is uniformly described by end. The specific connection relationship is subject to the actual application circuit. The same applies to the subsequent embodiments. The embodiments of the present invention will not elaborate further on this.

[0025] Optionally, in this embodiment of the invention, the above embodiments may include a load drive control logic for initializing a load short-circuit protection circuit. Specifically, after receiving a first target signal from the controller (such as a level enable signal or a specific logic level), the protection control module will release the blockade on the drive control module 10 or provide it with operating conditions. At this time, the drive control module 10 will be able to be controlled by a second target signal sent by the controller, such as a PWM wave or a switching level signal, thereby turning on or off its internal power switch to drive the load to operate normally. In this mode, the protection control module 20 is in a high-impedance state or an unaffected state.

[0026] Optionally, the above embodiments may further include a short-circuit detection and protection control logic, i.e., a protection control module, which can continuously or periodically analyze the detected electrical signals of the load, such as voltage, current, or power signals obtained through voltage division or other methods. When the detected electrical signal exceeds or falls below a preset safety threshold range, it indicates that the load is malfunctioning, and the protection control module will generate a protection trigger signal accordingly. The aforementioned protection trigger signal can be used to represent the detection result, such as a level transition signal. When the protection trigger signal is determined to indicate a load short circuit, the protection control module 20 will immediately execute a protection action: on the one hand, it will conduct its own internal path according to the trigger signal, such as turning on a pull-down switch to forcibly pull down the relevant node potential; on the other hand, this action will directly or indirectly cause the drive control module 10 to shut down, such as pulling down its gate drive voltage, thereby quickly cutting off the current flowing to the load, preventing the fault from spreading, and protecting the drive transistor and power supply.

[0027] As can be seen, implementing this invention enables the protection control module to receive the first target signal as a primary controller to initialize the circuit, thereby improving the controllability and stability of the load short-circuit protection circuit. This helps ensure that the hardware protection logic of the load short-circuit protection circuit is in a non-intervention state before the load drive starts, preventing malfunctions, improving the accuracy of load short-circuit protection, and enhancing the startup safety of subsequent hardware-based load short-circuit protection logic. After the protection control module controls the drive control module as a secondary controller, controlled by the second target signal sent by the controller, to drive the load based on the first target signal, the protection control module can determine whether the load is short-circuited based on the detected electrical signal of the load, without any intervention from the controller software program. At the instant the load short circuit occurs, the protection control module is turned on and the drive control module is turned off according to the protection trigger signal. This ensures that the load short-circuit protection action is completed by the interlocking relationship between the drive control module and the protection control module at the instant the load short circuit occurs, improving the efficiency of load short-circuit protection, timely cutting off the fault current, and preventing damage to sensitive power switching devices due to instantaneous large currents. This, in turn, helps improve the safety and lifespan of the entire drive circuit, achieving fast and self-consistent hardware-level safety protection.

[0028] In this embodiment of the invention, as an optional implementation, such as Figure 2 As shown, the protection control module 20 mentioned above includes a short-circuit control module 201 and a detection and analysis module 202, wherein: The first end of the short circuit control module 201 is electrically connected to the first end of the detection and analysis module 202, the second end of the short circuit control module 201 is electrically connected to the first end of the drive control module 10, the third end of the short circuit control module 201 is used to electrically connect to the controller, and the second end of the detection and analysis module 202 is electrically connected to the second end of the drive control module 10 and is also used to electrically connect to the load. The short-circuit control module 201 is used to control the drive control module 10 to be controlled by the second target signal sent by the controller, so as to drive the load, according to the first target signal received from the controller; The detection and analysis module 202 is used to generate a protection trigger signal based on the detected electrical signal of the load, and to determine whether the protection trigger signal is used to indicate a load short circuit. The short-circuit control module 201 is also used to turn on the protection control module 20 and turn off the drive control module 10 according to the protection trigger signal when the detection and analysis module 202 determines that the protection trigger signal is used to indicate a load short circuit.

[0029] In this embodiment of the invention, optionally, the core function of the short-circuit control module is as a "gating" mechanism for drive enable. Under normal conditions, upon receiving the first target signal (such as level enable) from the controller, the module's internal logic (e.g., through a switching transistor) allows the gate drive circuit of the drive control module 10 to operate normally, thereby enabling the drive control module 10 to respond to the controller's second target signal.

[0030] Optionally, the core function of the detection and analysis module is to detect the electrical signals of the load in real time, such as the voltage between the load and ground. It can also perform calculations using other electrical signals to characterize whether the load is short-circuited. Internally, it can include comparison circuits, such as a resistor divider network comparing with a reference, or a logic judgment unit to process the detection signal and generate a protection trigger signal. It determines whether the level or logic state of the trigger signal indicates a load short circuit. For example, when the voltage at the detection point is higher or lower than a set short-circuit threshold, it is determined to be a short circuit, and it outputs a valid protection trigger signal (such as a high level), or immediately uses the high voltage to trigger the short-circuit control module to further activate the protection control module and deactivate the drive control module.

[0031] Optionally, regarding the execution of protection actions: when the detection and analysis module determines a short circuit and outputs a valid protection trigger signal (or immediately utilizes this electrical signal), this signal will act on the short-circuit control module 201. In response to this signal, the short-circuit control module 201 quickly changes its internal state, opening the path between its first and second terminals, such as pulling down the node connected to the gate of the drive control module, thereby turning off the drive control module. Simultaneously, it can also enter a low-resistance on-state, ensuring the protection state is locked.

[0032] As can be seen, implementing this optional embodiment can improve the accuracy and efficiency of the load short-circuit protection logic by subdividing the protection control module into a short-circuit control module and a detection and analysis module. This facilitates the separation of detection and judgment functions from protection execution functions, allowing each part to be optimized independently. Consequently, it further enhances the accuracy and response speed of protection, enabling more refined fault management. Furthermore, by having the detection and analysis module dedicated to signal detection and judgment, it improves the accuracy and anti-interference capability of short-circuit judgment, thereby reducing false protection caused by signal noise or normal transient processes. This, in turn, improves the stability and continuity of system operation, achieving reliable and intelligent fault identification. Finally, by having the short-circuit control module dedicated to receiving control signals and executing shutdown operations, it enhances the driving capability and reliability of the protection execution stage. This ensures that a sufficiently strong control signal can be generated to quickly shut down the main circuit when protection is needed, thus guaranteeing the thoroughness and effectiveness of protection actions and achieving robust safety isolation.

[0033] In this embodiment of the invention, as another optional implementation, such as Figure 3 As shown, the drive control module 10 described above includes a switch control module 101 and a drive protection module 102, wherein: The first end of the switch control module 101 is electrically connected to the first end of the drive protection module 102, the second end of the switch control module 101 is electrically connected to the second end of the protection control module 20 and is used to electrically connect to the load, the second end of the drive protection module 102 is electrically connected to the first end of the protection control module 20, and the third end of the drive protection module 102 is used to electrically connect to the controller. The drive protection module 102 is used to turn on the switch control module 101 to drive the load in response to a second target signal; and to turn off the switch control module 101 in response to a protection trigger signal.

[0034] In this embodiment of the invention, optionally, the switching control module can be composed of a power switching transistor, such as an NMOS transistor, with its source grounded and its drain connected to the load. It is the final actuator controlling the on / off state of the load current.

[0035] Optionally, the drive protection module may include integrated drive circuitry and logic functions. In normal operation mode, when the protection control module fails to activate, the drive protection module responds to the second target signal. At this time, the drive protection module provides a suitable drive voltage to the control terminal (gate) of the switch control module through its internal pull-up and current-limiting network, thereby turning on the switch control module and driving the load. In protection mode, when the drive protection module receives a valid protection trigger signal (e.g., a pull-down signal) from the protection control module, it immediately cuts off the drive current supplied to the gate of the switch control module and quickly pulls its gate potential low through a pull-down resistor, ensuring that the switch control module is reliably turned off.

[0036] As can be seen, implementing this optional embodiment can improve the flexibility and safety of drive control by subdividing the drive control module into a switch control module and a drive protection module. This facilitates the separation of the power switch execution from the interface of drive signal conditioning and protection logic, which in turn allows for circuit optimization for drive and protection requirements, achieving efficient and safe power drive. Furthermore, the drive protection module can respond to the second target signal and protection trigger signal, improving the intelligence and robustness of the drive channel. This facilitates the integration of normal drive and emergency shutdown control logic into one, simplifying the main controller's control strategy. Ultimately, this helps ensure effective control of the power switch under any circumstances, realizing an intelligent interface that integrates drive and protection.

[0037] In this optional embodiment, as an optional implementation method, such as Figure 4As shown, the short-circuit control module 201 includes a switching transistor Q8 and a current-limiting resistor R38; the detection and analysis module 202 includes a voltage divider resistor R34 and a voltage divider resistor R37, wherein: The first terminal of the switching transistor Q8 is electrically connected to one end of the voltage divider resistor R34, one end of the voltage divider resistor R37, and one end of the current limiting resistor R38. The second terminal of the switching transistor Q8 is electrically connected to the other end of the voltage divider resistor R37 and is used for grounding. The third terminal of the switching transistor Q8 is electrically connected to the first terminal of the drive control module 10. The other end of the voltage divider resistor R34 is electrically connected to the second terminal of the drive control module 10 and is used for electrical connection to the load. The other end of the current limiting resistor R38 is used for electrical connection to the controller.

[0038] In this embodiment of the invention, optionally, the specific circuit of the short-circuit control module may include: the module mainly consists of a switching transistor Q8 (e.g., an NPN transistor or an N-channel MOSFET) and a current-limiting resistor R38. The first terminal (e.g., base or gate) of the switching transistor Q8 is connected to the controller's moto_mos pin through the current-limiting resistor R38 to receive the first target signal (enable signal EN). The second terminal (e.g., emitter or source) of the switching transistor Q8 is grounded. The third terminal (e.g., collector or drain) of the switching transistor Q8 is connected to the first terminal of the drive control module (e.g., the controlled input terminal of the drive protection module). When the controller outputs a low-level enable signal, the current is limited by R38, preventing Q8 from conducting and pulling up the potential of its collector or drain (third terminal), i.e. Figure 4 Point A is left floating, allowing it to be controlled by the controller's MOS-driver pin, thus enabling the drive control module to operate. This high-level setting is one of the logic conditions for normal enable.

[0039] Optionally, the specific circuit of the detection and analysis module is as follows: This module mainly consists of voltage divider resistors R34 and R37. One end of R34 is connected to the second terminal of the drive control module (i.e., the drain of the switch control module 101, which is the load voltage point M-), and the other end is connected to one end of R37 and the first terminal of the switching transistor Q8. The other end of R37 is grounded. These two resistors form a voltage divider network. The voltage at point M- (i.e., the voltage to ground across the load) is divided by R34 and R37, forming a detection voltage V_DET at their connection point B (i.e., the intersection of R34, R37, and the base of Q8). When the load is working normally, M- is low, and the voltage at point B is low enough to turn on Q8. When a short circuit to ground occurs in the load, M- is forced high, causing the voltage at point B to increase significantly, i.e., become high. This high-level signal constitutes the protection trigger signal. Since this point is directly connected to the base of Q8, a high level will turn on Q8, thereby disabling the drive control module. When point A is low, Q7 is off, disconnecting the load and protecting the circuit. Here, the resistance ratio of resistors R34 and R37 determines the voltage threshold for short-circuit detection. Further optionally, when the load enters normal operation, i.e., when Q8 is not conducting and Q7 is conducting, the controller moto_mos pin can be set to the input state, so that the controller detects the level state of this IO port pin. That is, in the embodiment of the invention, in addition to the above-mentioned hardware characteristics detecting the level state of point B, the controller can also synchronously detect the level state of point B.

[0040] As can be seen, implementing this optional embodiment can achieve short-circuit control and detection analysis functions by using discrete components such as switching transistor Q8 and resistors R34, R37, and R38, improving the circuit's implementation efficiency and economy. This facilitates the construction of reliable protection circuits using discrete components, reduces hardware costs, and promotes the application of this technology in mass-produced products, achieving cost-effective short-circuit protection. The protection point can be set through a threshold network composed of voltage divider resistors R34 and R37, improving the settling ability and stability of the short-circuit judgment threshold. This allows for flexible adjustment of protection sensitivity by selecting resistors of different values ​​to adapt to different application scenarios, thereby improving the circuit's adaptability and customizability, and achieving flexible and reliable voltage detection and threshold judgment. The controller can be connected via a current-limiting resistor R38, improving the safety of the controller interface. This helps limit the current flowing into the controller pins, preventing damage to the interface circuit due to abnormal voltage or current, thus improving the reliability and durability of the entire control system and achieving effective protection for the microcontroller.

[0041] In this optional embodiment, as another alternative implementation, such as Figure 4As shown, the switch control module 101 includes a switch transistor Q7; the drive protection module 102 includes a drive pull-up resistor R32, a drive and current limiting resistor R33, and a gate pull-down resistor R35, wherein: The first terminal of the switching transistor Q7 is electrically connected to one end of the gate pull-down resistor R35 and one end of the drive and current limiting resistor R33. The second terminal of the switching transistor Q7 is electrically connected to the second terminal of the protection control module 20 and is used to electrically connect to the load. The third terminal of the switching transistor Q7 and the other end of the gate pull-down resistor R35 are used for grounding. The other end of the drive and current limiting resistor R33 is electrically connected to the first terminal of the protection control module 20 and one end of the drive pull-up resistor R32. The other end of the drive pull-up resistor R32 is used to electrically connect to the controller.

[0042] In this embodiment of the invention, optionally, the specific circuit of the switch control module is as follows: the module mainly consists of a switching transistor Q7 (e.g., a power MOSFET). The first terminal (gate G) of Q7 receives the drive signal. The second terminal (drain D) of Q7 is connected to the second terminal of the protection control module 20 and the load, serving as the power output terminal. The third terminal (source S) of Q7 is grounded.

[0043] Further optional, the specific circuitry of the drive protection module includes a drive pull-up resistor R32, a drive and current-limiting resistor R33, and a gate pull-down resistor R35. One end of R32 is connected to the controller to receive the second target signal. The other end of R32 is connected to one end of R33 and the first terminal of the protection control module 20. The other end of R33 is connected to the gate (G) of the switching transistor Q7. R35 is connected between the gate (G) of Q7 and ground.

[0044] Optionally, during normal operation, the first terminal of the protection control module 20 is in a high-impedance state or an ineffective protection state, which can be controlled by the controller's MOSFET pin. Pulling the MOSFET high turns on Q7, allowing the load to operate. When the controller outputs a high-level PWM signal, current flows through R32 and R33, charging the gate of Q7 and turning it on. R32 acts as a pull-up and current limiter, while R33 further limits the current and may adjust the drive speed. R35 ensures that the gate of Q7 is reliably pulled down to ground when there is no drive signal, preventing false turn-on. When the protection control module 20 activates (its first terminal outputs a valid pull-down protection signal), this point is forcibly pulled low. Therefore, regardless of the controller's MOSFET pin signal, the current through R32 and R33 is bypassed, preventing sufficient voltage from being supplied to the gate of Q7. Simultaneously, R35 ensures rapid gate discharge, achieving rapid turn-off.

[0045] As can be seen, implementing this optional embodiment enables main switch control using a switching transistor Q7, and combines it with resistors R32, R33, and R35 to form drive protection, improving the efficiency and reliability of the power drive stage. This facilitates the utilization of the high efficiency and low loss characteristics of switching transistors such as MOSFETs, and the resistor network ensures the quality of the gate drive signal, thereby reducing power loss, improving system efficiency, and achieving efficient and reliable power switching. The pull-up resistor R32 and the drive and current-limiting resistor R33 enhance the drive capability and switching speed controllability of the gate drive signal, providing a fast and sufficient charging current to the gate of switching transistor Q7 and suppressing gate oscillation. This optimizes the switching characteristics of the transistor, reduces switching losses and electromagnetic interference, and achieves clean and efficient switching action. The pull-down resistor R35 improves the turn-off reliability of switching transistor Q7 in static conditions, allowing the gate potential to be explicitly pulled low in the absence of a valid drive signal, preventing false turn-on due to interference or leakage. This enhances the static stability and safety of the system, achieving a reliable fail-safe mechanism.

[0046] In this embodiment of the invention, as another optional implementation, such as Figure 4 As shown, the load short-circuit protection circuit also includes a data acquisition and feedback module 30, wherein: The first end of the data acquisition and feedback module 30 is electrically connected to the fourth end of the drive control module 10 and the fourth end of the protection control module 20, and the second end of the data acquisition and feedback module 30 is used to electrically connect to the controller. The data acquisition and feedback module 30 is used to sample the current flowing through the load and generate a corresponding current feedback signal to feed back to the controller.

[0047] In this embodiment of the invention, optionally, the first terminal of the acquisition feedback module is electrically connected to the fourth terminal of the drive control module (such as the source of the power switch or the current sampling point) and the fourth terminal of the protection control module (such as the common ground terminal or the current loop point). Its second terminal is connected to the Moto_Current pin of the controller. The core function of this module is to sample the current flowing through the load. Specifically, it obtains current information by measuring the voltage drop across a known-value sampling resistor. Subsequently, the module processes this voltage drop signal (possibly including amplification, level shifting, and filtering) to generate a corresponding current feedback signal (such as a voltage signal proportional to the current) and feeds it back to the controller. Based on this feedback signal, the controller can monitor the load current in real time, enabling advanced functions such as overcurrent warning and speed / torque closed-loop control, and providing additional judgment criteria for short-circuit protection.

[0048] As can be seen, implementing this optional embodiment can improve the observability and intelligent management level of the system status by sampling the load current through the addition of a data acquisition and feedback module. This is beneficial for providing the controller with real-time load current data, realizing overcurrent and stall protection and status monitoring at the software level, and thus helping to form a dual protection mechanism that complements hardware protection, achieving comprehensive safety monitoring. The data acquisition and feedback module can provide current feedback signals, improving the accuracy and adaptability of control, which is beneficial for realizing advanced functions such as closed-loop control, efficiency optimization or fault diagnosis based on actual load current. This, in turn, helps to improve the overall performance and intelligence level of the product, and achieve more refined energy management and fault early warning.

[0049] In this optional embodiment, as an optional implementation method, such as Figure 4 As shown, the aforementioned acquisition feedback module 30 includes a sampling resistor R39, a bias resistor R36, and a filter capacitor C12, wherein: One end of the sampling resistor R39 is electrically connected to one end of the bias resistor R36 and the fourth terminal of the drive control module 10. The other end of the sampling resistor R39 is electrically connected to the fourth terminal of the protection control module 20 and is used for grounding. The other end of the bias resistor R36 is electrically connected to one end of the filter capacitor C12 and is used for electrical connection to the controller. The other end of the filter capacitor C12 is used for grounding.

[0050] In this embodiment of the invention, optionally, the acquisition feedback module may include a sampling resistor R39, a bias resistor R36, and a filter capacitor C12. The sampling resistor R39 is connected in series in the main circuit of the load current. Specifically, one end is connected to the fourth terminal of the drive control module (such as the source of the switching transistor Q7), and the other end is connected to the fourth terminal of the protection control module 20 and grounded. Thus, all the load current flows through R39. One end of the bias resistor R36 is connected to the connection point between the sampling resistor R39 and the fourth terminal of the drive control module 10, and the other end is connected to an ADC (analog-to-digital converter) input pin of the controller, providing bias. The filter capacitor C12 is connected between the ADC input pin and ground.

[0051] Optionally, when the load current I_LOAD flows through the sampling resistor R39, a voltage drop V_SENSE = I_LOAD * R39 is generated across it. This voltage signal (negative or a small voltage relative to ground) is transmitted to the controller's ADC pin through the bias resistor R36. The ADC pin typically requires a positive voltage input; therefore, in practical applications, a pull-up bias voltage can be provided at the other end of R36, or the controller's internal ADC can be configured as a differential input or have negative voltage detection capability to correctly read this voltage. The filter capacitor C12 is used to filter out high-frequency noise in the sampling signal, providing a stable ADC input. The controller reads this voltage value and calculates the real-time load current value.

[0052] As can be seen, implementing this optional embodiment enables current sampling through sampling resistor R39, bias resistor R36, and filter capacitor C12, improving the accuracy and signal-to-noise ratio of the current sampling signal. This facilitates the linear conversion of the load current into a clean voltage signal, enabling precise sampling by the controller. Consequently, it improves the accuracy and reliability of the software protection algorithm, achieving high-precision current feedback. Furthermore, the filter capacitor C12 filters out high-frequency noise in the sampling signal, improving the stability of the current feedback signal. This helps avoid controller misjudgments caused by noise interference, reducing system malfunctions. Ultimately, it enhances the system's operational stability in complex electromagnetic environments, achieving robust and reliable signal acquisition.

[0053] In an optional embodiment, such as Figure 4 As shown, the load short-circuit protection circuit also includes a power input and filtering module 40, wherein: The first end of the power input and filtering module 40 is electrically connected to the second end of the drive control module 10 and the second end of the protection control module 20. The second end of the power input and filtering module 40 is used to electrically connect to the load, and the third end of the power input and filtering module 40 is used to electrically connect to the power supply. The power input and filtering module 40 is used to receive external power, and after performing reverse connection protection and filtering, it supplies power to the circuit.

[0054] In this embodiment of the invention, optionally, the first terminal of the power input and filtering module is connected to the second terminal of the drive control module and the second terminal of the protection control module. The second terminal is used to connect to the load, and the connection point is as follows: Figure 4The circuit consists of a positive M+ pin for the load and a negative M- pin for the load. The third pin is used to connect to an external power supply (BAT+, such as a +12V or +24V DC power supply). Its main functions are: 1. To receive external power and provide energy to the circuit. 2. To provide reverse connection protection, preventing damage to semiconductor devices in the circuit due to reversed power polarity. 3. To perform filtering / decoupling, suppressing noise and ripple on the power line, and providing energy storage for the instantaneous current demand of the load, ensuring the stability of the circuit's operating voltage.

[0055] As can be seen, implementing this optional embodiment can improve the purity and stability of power supply quality by adding a power input and filtering module, which is conducive to providing low-noise and stable operating voltage for subsequent drive and protection circuits, reducing the impact of power supply interference on sensitive circuits, and thus helping to ensure the accuracy of protection logic and drive control, and achieving high reliability of the circuit's basic power supply environment.

[0056] In this optional embodiment, as an optional implementation method, such as Figure 4 As shown, the power input and filtering module 40 mentioned above includes a reverse connection protection diode D3 and a filter / decoupling capacitor C5, wherein: One end of the reverse polarity protection diode D3 is electrically connected to one end of the filter / decoupling capacitor C5, the second end of the drive control module 10, and the second end of the protection control module 20, and is used to electrically connect to the negative potential end of the load. The other end of the reverse polarity protection diode D3 is electrically connected to the other end of the filter / decoupling capacitor C5, and is used to electrically connect to the positive potential end of the power supply and the load.

[0057] As can be seen, implementing this optional embodiment can improve the circuit's tolerance to power supply polarity errors through the reverse connection protection diode D3, thereby facilitating the automatic disconnection of the power supply circuit in the event of an accidental reverse connection, protecting subsequent circuit components from damage, and thus reducing the failure rate during production assembly and user use, improving the product's robustness and durability; it can also improve the power supply's transient response and anti-interference capability through the filter / decoupling capacitor C5, thereby providing energy buffer for instantaneous high current demands such as motor startup, and suppressing voltage fluctuations and noise on the power line, thus ensuring stable operation of the circuit under dynamic load changes and achieving stable and reliable power supply support.

[0058] Example 2 This invention discloses a dough pressing machine, which includes the load short-circuit protection circuit described in Embodiment 1.

[0059] In this embodiment of the invention, optionally, the load in the dough press machine can be a motor driving the dough rollers. The load short-circuit protection circuit is integrated into the motor drive control board of the dough press machine. The controller of the circuit is the main control MCU of the dough press machine. The load (motor) is connected to the load output terminal of the above circuit. The power input and filtering module is connected to the internal DC power supply of the dough press machine (such as a 24VDC output from a switching power supply). The first target signal (enable signal) and the second target signal (PWM speed control signal) of the controller are generated by the main control MCU according to user operation or a preset program.

[0060] When the user starts the dough press, the MCU first outputs a first target signal (low level) to enable the protection control module, and then outputs a second target signal (PWM wave) to control the drive control module to drive the motor. The detection and analysis module monitors the motor terminal voltage in real time. In the event of a short circuit in the motor coil or driver, the detection and analysis module immediately triggers protection, shutting down the drive through the short-circuit control module to protect the power switching transistors and the power supply system. Simultaneously, the acquisition and feedback module (if equipped) can feed the motor current back to the MCU for overload protection or torque control. The power input and filtering module ensures a stable, reverse-connection-protected power supply to the entire drive circuit.

[0061] By applying this load short-circuit protection circuit, the reliability and safety of the motor drive system of the dough press equipment are significantly improved, preventing equipment damage or safety accidents caused by short-circuit faults.

[0062] As can be seen, implementing the embodiments of the present invention can improve the safety and reliability of the noodle press motor drive system by integrating the above-mentioned load short-circuit protection circuit. This facilitates rapid power cut-off in extreme fault situations such as motor wiring harness short circuits, protecting the core control board and significantly reducing after-sales repair rates and safety risks, thus achieving a high safety and long lifespan design for the noodle press product. The fast and reliable short-circuit protection mechanism improves the continuity of noodle press operation and user experience, helping to avoid serious consequences such as machine burnout due to minor faults and shortening fault recovery time (e.g., normal operation is restored after the short circuit is cleared). This, in turn, enhances the product's market competitiveness and user satisfaction, resulting in a safe and durable kitchen appliance.

[0063] The above provides a detailed description of a load short-circuit protection circuit and a dough press machine according to embodiments of the present invention. Specific embodiments have been used to illustrate the principles and implementation methods of the present invention. However, the above preferred embodiments are not intended to limit the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention is determined by the scope defined in the claims.

Claims

1. A load short-circuit protection circuit, characterized in that, The circuit includes a drive control module (10) and a protection control module (20), wherein: The first end of the drive control module (10) is electrically connected to the first end of the protection control module (20), the second end of the drive control module (10) and the second end of the protection control module (20) are used to electrically connect to the load, and the third end of the drive control module (10) and the third end of the protection control module (20) are used to electrically connect to the controller. The protection control module (20) is used to control the drive control module (10) to be controlled by the second target signal sent by the controller according to the first target signal received from the controller, so as to drive the load; The protection control module (20) is also used to generate a protection trigger signal based on the detected electrical signal of the load; when the protection trigger signal is used to indicate that the load is short-circuited, the protection control module (20) is turned on and the drive control module (10) is turned off based on the protection trigger signal.

2. The load short-circuit protection circuit according to claim 1, characterized in that, The protection control module (20) includes a short-circuit control module (201) and a detection and analysis module (202), wherein: The first end of the short-circuit control module (201) is electrically connected to the first end of the detection and analysis module (202), the second end of the short-circuit control module (201) is electrically connected to the first end of the drive control module (10), the third end of the short-circuit control module (201) is used to electrically connect to the controller, and the second end of the detection and analysis module (202) is electrically connected to the second end of the drive control module (10) and is also used to electrically connect to the load. The short-circuit control module (201) is used to control the drive control module (10) to be controlled by the second target signal sent by the controller according to the first target signal received from the controller, so as to drive the load; The detection and analysis module (202) is used to generate a protection trigger signal based on the detected electrical signal of the load; and to determine whether the protection trigger signal is used to indicate that the load is short-circuited; The short-circuit control module (201) is also used to turn on the protection control module (20) and turn off the drive control module (10) according to the protection trigger signal when the detection and analysis module (202) determines that the protection trigger signal is used to indicate that the load is short-circuited.

3. The load short-circuit protection circuit according to claim 1, characterized in that, The drive control module (10) includes a switch control module (101) and a drive protection module (102), wherein: The first end of the switch control module (101) is electrically connected to the first end of the drive protection module (102), the second end of the switch control module (101) is electrically connected to the second end of the protection control module (20) and is used to electrically connect the load, the second end of the drive protection module (102) is electrically connected to the first end of the protection control module (20), and the third end of the drive protection module (102) is used to electrically connect the controller; The drive protection module (102) is configured to turn on the switch control module (101) in response to the second target signal to drive the load; and to turn off the switch control module (101) in response to the protection trigger signal.

4. The load short-circuit protection circuit according to claim 2, characterized in that, The short-circuit control module (201) includes a switching transistor Q8 and a current-limiting resistor R38; the detection and analysis module (202) includes a voltage divider resistor R34 and a voltage divider resistor R37, wherein: The first end of the switching transistor Q8 is electrically connected to one end of the voltage divider resistor R34, one end of the voltage divider resistor R37 and one end of the current limiting resistor R38. The second end of the switching transistor Q8 is electrically connected to the other end of the voltage divider resistor R37 and is used for grounding. The third end of the switching transistor Q8 is electrically connected to the first end of the drive control module (10). The other end of the voltage divider resistor R34 is electrically connected to the second end of the drive control module (10) and is used for electrical connection to the load. The other end of the current limiting resistor R38 is used for electrical connection to the controller.

5. The load short-circuit protection circuit according to claim 3, characterized in that, The switch control module (101) includes a switch transistor Q7; the drive protection module (102) includes a drive pull-up resistor R32, a drive and current-limiting resistor R33, and a gate pull-down resistor R35, wherein: The first terminal of the switching transistor Q7 is electrically connected to one end of the gate pull-down resistor R35 and one end of the drive and current limiting resistor R33. The second terminal of the switching transistor Q7 is electrically connected to the second terminal of the protection control module (20) and is used to electrically connect to the load. The third terminal of the switching transistor Q7 and the other end of the gate pull-down resistor R35 are used to ground. The other end of the drive and current limiting resistor R33 is electrically connected to the first terminal of the protection control module (20) and one end of the drive pull-up resistor R32. The other end of the drive pull-up resistor R32 is used to electrically connect to the controller.

6. The load short-circuit protection circuit according to any one of claims 1-5, characterized in that, The circuit also includes a data acquisition and feedback module (30), wherein: The first end of the acquisition feedback module (30) is electrically connected to the fourth end of the drive control module (10) and the fourth end of the protection control module (20), and the second end of the acquisition feedback module (30) is used to electrically connect to the controller; The acquisition and feedback module (30) is used to sample the current flowing through the load and generate a corresponding current feedback signal to feed back to the controller.

7. The load short-circuit protection circuit according to claim 6, characterized in that, The acquisition and feedback module (30) includes a sampling resistor R39, a bias resistor R36, and a filter capacitor C12, wherein: One end of the sampling resistor R39 is electrically connected to one end of the bias resistor R36 and the fourth terminal of the drive control module (10). The other end of the sampling resistor R39 is electrically connected to the fourth terminal of the protection control module (20) and is used for grounding. The other end of the bias resistor R36 is electrically connected to one end of the filter capacitor C12 and is used for electrical connection to the controller. The other end of the filter capacitor C12 is used for grounding.

8. The load short-circuit protection circuit according to any one of claims 1-5, characterized in that, The circuit also includes a power input and filtering module (40), wherein: The first end of the power input and filtering module (40) is electrically connected to the second end of the drive control module (10) and the second end of the protection control module (20). The second end of the power input and filtering module (40) is used to electrically connect to the load. The third end of the power input and filtering module (40) is used to electrically connect to the power supply. The power input and filtering module (40) is used to receive the external power supply, and after performing reverse connection protection and filtering on the power supply, it supplies power to the circuit.

9. The load short-circuit protection circuit according to claim 8, characterized in that, The power input and filtering module (40) includes a reverse connection protection diode D3 and a filter / decoupling capacitor C5, wherein: One end of the reverse polarity protection diode D3 is electrically connected to one end of the filter / decoupling capacitor C5, the second end of the drive control module (10), and the second end of the protection control module (20), and is used to electrically connect to the negative potential end of the load. The other end of the reverse polarity protection diode D3 is electrically connected to the other end of the filter / decoupling capacitor C5, and is used to electrically connect to the positive potential end of the power supply and the load.

10. A dough pressing machine, characterized in that, The noodle pressing machine includes a load short-circuit protection circuit as described in any one of claims 1-9.

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