Power supply module and electric tool

Abstract

The utility model provides a power supply module and an electric tool. The power supply module comprises a power supply processing circuit, a current acquisition circuit and a master control circuit. The input end of the power processing circuit is connected with the output end of the motor; the input end of the current acquisition circuit is connected with the output end of the power supply processing circuit; the first output end of the current acquisition circuit is connected with the input end of the motor; the input end of the main control circuit is connected with the second output end of the current acquisition circuit. The power supply processing circuit is used for processing a working power supply of the motor and then outputting corresponding electric energy; the current acquisition circuit is used for acquiring electric energy output by the power supply processing circuit and outputting a corresponding current acquisition signal according to the electric energy; the main control circuit is used for determining the current parameter of the motor according to the current acquisition signal of the current acquisition circuit. According to the utility model, peripheral circuits such as a current transformer and an operational amplifier in the prior art are replaced by the current acquisition circuit, so that a current acquisition function with higher efficiency, higher safety and lower cost is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of power modules, in particular to a power module and an electric tool. Background Art

[0002] AC speed switches have long been used in handheld industrial power tools, including wrenches, drills, and screwdrivers. These switches consist of a housing with a push-button switch, a gear adjustment knob, a speed control panel, a motor, and a vibrating contact. During operation, the gear adjustment knob changes the resistance value, and the control panel detects the gear position to control the speed motor, which then drives the transmission mechanism to achieve speed regulation. Conventional speed switches only provide a fixed output based on the gear position. When the load and gear position do not match, the current rises sharply, causing the motor to vibrate rapidly, resulting in low efficiency, poor performance, and potential injury to technicians. To avoid safety hazards, a control system that automatically adjusts the output is required. However, such a control system requires an internal power supply system, which typically utilizes peripheral circuits such as current transformers and operational amplifiers. This is not only bulky but also expensive to design. Utility Model Content

[0003] The main purpose of the utility model is to provide a power supply module and an electric tool, aiming to achieve a current acquisition function with higher efficiency, greater safety and lower cost.

[0004] The utility model proposes a power supply module, which includes: a power supply processing circuit, wherein the input end of the power supply processing circuit is used to connect to the output end of the motor; the power supply processing circuit is used to process the working power supply of the motor and output corresponding electric energy; a current acquisition circuit, wherein the input end of the current acquisition circuit is connected to the output end of the power supply processing circuit, and the first output end of the current acquisition circuit is used to connect to the input end of the motor; the current acquisition circuit is used to acquire the electric energy output by the power supply processing circuit and output a corresponding current acquisition signal according to the electric energy; a main control circuit, wherein the input end of the main control circuit is connected to the second output end of the current acquisition circuit; the main control circuit is used to determine the current parameters of the motor according to the current acquisition signal of the current acquisition circuit.

[0005] In one embodiment, the current acquisition circuit includes: a sampling resistor and a voltage divider resistor; the first end of the sampling resistor is the input end of the current acquisition circuit, the second end of the sampling resistor is connected to the first end of the voltage divider resistor, the connection point between the sampling resistor and the voltage divider resistor is the first output end of the current acquisition circuit, and the second end of the voltage divider resistor is the second output end of the current acquisition circuit.

[0006] In one embodiment, the power supply module further includes: a drive circuit, wherein a controlled end of the drive circuit is used to connect to the main control circuit, an input end of the drive circuit is connected to an output end of the current acquisition circuit, and an output end of the drive circuit is connected to an input end of the motor; the drive circuit is used to receive a PWM signal from the main control circuit and to open / close the path between the current acquisition circuit and the motor according to the PWM signal to regulate the current of the motor.

[0007] In one embodiment, the drive circuit includes: a first switching tube, wherein the input end of the first switching tube is the input end of the drive circuit, and the input end of the first switching tube is connected to the controlled end of the first switching tube, and the output end of the first switching tube is the output end of the drive circuit; a second switching tube, wherein the input end of the second switching tube is connected to the controlled end of the first switching tube, the controlled end of the second switching tube is the controlled end of the drive circuit, and the output end of the second switching tube is used to be connected to the ground end; the second switching tube is used to receive a PWM signal from the main control circuit and to open / close the path between the current acquisition circuit and the ground end according to the PWM signal; and the first switching tube is used to open the path between the current acquisition circuit and the motor when the path between the current acquisition circuit and the ground end is connected.

[0008] In one embodiment, the power processing circuit includes: a filter circuit, the input end of the voltage stabilizing circuit is used to connect to the input end of the motor; the filter circuit is used to filter the voltage of the working power supply of the motor and output a corresponding filter signal.

[0009] In one embodiment, the power processing circuit further includes: a voltage stabilizing circuit, wherein the input end of the voltage stabilizing circuit is connected to the output end of the filtering circuit, and the output end of the voltage stabilizing circuit is connected to the input end of the current acquisition circuit; the voltage stabilizing circuit is used to stabilize the voltage of the filtered signal and then output a corresponding voltage signal to the current acquisition circuit.

[0010] In one embodiment, the power processing circuit further includes: a rectifier circuit, wherein the input end of the rectifier circuit is connected to the output end of the voltage stabilizing circuit; the rectifier circuit is used to perform AC-DC conversion on the voltage of the voltage signal and output a corresponding DC signal.

[0011] In one embodiment, the power processing circuit also includes: an overcurrent protection circuit, the controlled end of the overcurrent protection circuit is connected to the output end of the rectifier circuit, the input end of the overcurrent protection circuit is used to connect to the power end, and the connection point between the input end of the overcurrent protection circuit and the power end is used to connect to the main control circuit, and the output end of the overcurrent protection circuit is used to connect to the ground end; the overcurrent protection circuit is used to disconnect the path between the power end and the ground end when the current of the rectifier circuit exceeds a preset current, and output a shutdown signal to the main control circuit.

[0012] In one embodiment, the power processing circuit further includes: a load interface, the input end of the load interface is used to connect to the motor, and the output end of the load interface is connected to the input end of the filter circuit; the load interface is used to establish a connection relationship between the filter circuit and the motor.

[0013] The utility model also provides an electric tool, comprising an electric motor and the power module.

[0014] The utility model provides a power supply module and an electric tool. The power supply module includes a power supply processing circuit, a current acquisition circuit, and a main control circuit. The input end of the power supply processing circuit is used to connect to the output end of the motor; the input end of the current acquisition circuit is connected to the output end of the power supply processing circuit, and the first output end of the current acquisition circuit is used to connect to the input end of the motor; the input end of the main control circuit is connected to the second output end of the current acquisition circuit. The power supply processing circuit is used to process the working power of the motor and output corresponding electrical energy; the current acquisition circuit is used to collect the electrical energy output by the power supply processing circuit and output a corresponding current acquisition signal based on the electrical energy; the main control circuit is used to determine the current parameters of the motor based on the current acquisition signal of the current acquisition circuit. The utility model replaces the existing current transformer, operational amplifier and other peripheral circuits with a current acquisition circuit, collects the current of the motor through the current acquisition circuit, and intelligently adjusts the speed of the motor according to the collected current, so that the motor maintains a stable and good working state, thereby extending the service life of the power tool, meeting the low cost and high performance requirements of the power tool, reducing the design cost of the power tool and reducing the size of the power tool, and achieving a more efficient, safer and lower-cost current acquisition function. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0016] Figure 1 This is a circuit flow chart of the power module of the utility model;

[0017] Figure 2 This is a circuit flow chart of another embodiment of the power module of the present utility model;

[0018] Figure 3 This is a specific circuit structure diagram of the power module of the utility model.

[0019] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0022] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if the meaning of "and / or" appearing in the full text is to include three parallel schemes, taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0023] AC speed switches have long been used in handheld industrial power tools, including wrenches, drills, and screwdrivers. These switches consist of a housing with a push-button switch, a gear adjustment knob, a speed control panel, a motor, and a vibrating contact. During operation, the gear adjustment knob changes the resistance value, and the control panel detects the gear position to control the speed motor, which then drives the transmission mechanism to achieve speed regulation. Conventional speed switches only provide a fixed output based on the gear position. When the load and gear position do not match, the current rises sharply, causing the motor to vibrate rapidly, resulting in low efficiency, poor performance, and potential injury to technicians. To avoid safety hazards, a control system that automatically adjusts the output is required. However, such a control system requires an internal power supply system, which typically utilizes peripheral circuits such as current transformers and operational amplifiers. This is not only bulky but also expensive to design.

[0024] Therefore, in order to achieve a more intelligent, more efficient, safer and lower-cost current acquisition function, the present invention proposes a power supply module, which includes:

[0025] A power processing circuit 10, wherein the input end of the power processing circuit 10 is connected to the output end of the motor; the power processing circuit 10 is used to process the working power of the motor and output corresponding electric energy;

[0026] a current acquisition circuit 20, wherein the input end of the current acquisition circuit 20 is connected to the output end of the power processing circuit 10, and the first output end of the current acquisition circuit 20 is used to connect to the input end of the motor; the current acquisition circuit 20 is used to collect the electric energy output by the power processing circuit and output a corresponding current acquisition signal based on the electric energy;

[0027] The main control circuit 30 has an input end connected to the second output end of the current acquisition circuit 20 ; the main control circuit 30 is used to determine the current parameters of the motor according to the current acquisition signal of the current acquisition circuit 20 .

[0028] It is understood that when a power module is used in an electric tool, it can automatically adjust the output current acquisition control circuit of the motor according to the working current acquisition control circuit of the motor in the electric tool, so that the working current acquisition control circuit of the motor matches the output current acquisition control circuit of the power module, thereby improving the operating efficiency of the motor and the safety of the motor. However, existing power modules are usually implemented using peripheral circuits such as current transformers and operational amplifiers, which are not only bulky but also have high design costs. In order to reduce the design cost and size of the electric tool while increasing the service life of the electric tool, the utility model proposes a power module that replaces the existing peripheral circuits such as current transformers and operational amplifiers with a current acquisition circuit 20. The current acquisition circuit 20 acquires the current of the motor in real time, and the main control circuit 30 intelligently adjusts the speed of the motor according to the acquired current, so that the motor maintains a stable and good working state, thereby extending the service life of the electric tool, meeting the low cost and high performance requirements of the electric tool, and realizing a more efficient, safer and lower cost current acquisition function.

[0029] In this embodiment, the power module mainly includes a power processing circuit 10, a current acquisition circuit 20, and a main control circuit 30. Optionally, the main control circuit 30 can be implemented using a main control chip, such as an MCU, a DSP (Digital Signal Processing) chip, or an FPGA (Field Programmable Gate Array). In this embodiment, the main control circuit 30 is implemented using a main control chip.

[0030] The power module also includes a load interface LIN and a load interface LOUT, wherein the load interface LOUT is specifically the live wire output terminal. The input terminal of the power processing circuit 10 is connected to the output terminal of the motor via the load interface LIN; the input terminal of the current acquisition circuit 20 is connected to the output terminal of the power processing circuit 10, and the first output terminal of the current acquisition circuit 20 is connected to the input terminal of the motor via the load interface LOUT; the input terminal of the main control circuit 30 is connected to the second output terminal of the current acquisition circuit 20. In addition, the power module also includes interfaces H1, H2, H4, H5, and H6. Interface H1 is a power input interface for connecting to the power input and providing the operating voltage required by the circuit; interface H2 is a 5V power input interface; interface H4 is used to detect the potentiometer as the basis for gear input; interface H5 is used to connect to an external load to output a PWM signal to the external load; interface H6 is the neutral wire input terminal.

[0031] In practical applications, the input of the power processing circuit 10 is connected to the motor, and the circuit processes the motor's operating power before outputting corresponding electrical energy. The specific processing may include filtering, rectification, and voltage stabilization. When the power processing circuit 10, current acquisition circuit 20, and main control chip form a closed loop, the current acquisition circuit 20 collects the electrical energy output by the power processing circuit and outputs a corresponding current acquisition signal to the main control chip based on the electrical energy. It should be understood that if the power processing circuit 10, current acquisition circuit 20, and main control chip cannot form a closed loop, the current acquisition circuit 20 cannot collect the electrical energy output by the power processing circuit 10. The main control chip controls the sampling frequency of the current acquisition signal, collects multiple current acquisition signals output by the current acquisition circuit 20, and performs analog-to-digital conversion on the multiple current acquisition signals to obtain multiple current values. The average of the multiple current values is then calculated, and the average value is ultimately used as the current parameter of the motor. The main control chip detects whether the motor's operating state is abnormal based on the motor's current and adjusts the motor's current to adjust the motor's speed. This prevents the motor's current from fluctuating and the tool from shaking, enhancing the user experience. When the motor's feedback current is high, the main control chip increases the output conduction angle, making the motor run faster and more energy-efficient, thereby improving the efficiency of the power tool.

[0032] The present invention provides a power supply module comprising a power processing circuit 10, a current acquisition circuit 20, and a main control circuit 30. The input of the power processing circuit 10 is connected to the output of the motor via a load interface LIN; the input of the current acquisition circuit 20 is connected to the output of the power processing circuit 10, and the first output of the current acquisition circuit 20 is connected to the input of the motor via a load interface LOUT; and the input of the main control circuit 30 is connected to the second output of the current acquisition circuit 20. The power processing circuit 10 processes the working power of the motor and outputs corresponding electrical energy; the current acquisition circuit 20 collects the electrical energy processed by the power supply and outputs a corresponding current acquisition signal based on the electrical energy; and the main control circuit 30 determines the current parameters of the motor based on the current acquisition signal from the current acquisition circuit 20. The present utility model proposes a power supply module, which replaces existing peripheral circuits such as current transformers and operational amplifiers with a current acquisition circuit 20. The current acquisition circuit 20 acquires the current of the motor and intelligently adjusts the speed of the motor according to the acquired current, so that the motor maintains a stable and good working state, thereby extending the service life of the power tool, meeting the low cost and high performance requirements of the power tool, reducing the design cost of the power tool and reducing the size of the power tool, and achieving a more efficient, safer and lower-cost current acquisition function.

[0033] In one embodiment, the current acquisition circuit 20 includes:

[0034] Sampling resistor R1 and voltage divider resistor R2;

[0035] The first end of the sampling resistor R1 is the input end of the current acquisition circuit 20, the second end of the sampling resistor R1 is connected to the first end of the voltage divider resistor R2, the connection point between the sampling resistor R1 and the voltage divider resistor R2 is the first output end of the current acquisition circuit 20, and the second end of the voltage divider resistor R2 is the second output end of the current acquisition circuit 20.

[0036] It will be appreciated that, in this embodiment, the current acquisition circuit 20 is implemented using a sampling resistor R1 and a voltage-divider resistor R2. The connection point between the sampling resistor R1 and the voltage-divider resistor R2 is connected to the input terminal of the motor. In actual applications, when the power processing circuit 10, the sampling resistor R1, and the motor form a closed loop, the electric energy output by the power processing circuit 10 passes through the sampling resistor R1 and the voltage-divider resistor R2. After the electric energy is collected and processed by the sampling resistor R1 and the voltage-divider resistor R2, the corresponding current sampling signal is output to the main control circuit 30. The main control circuit 30 receives multiple current sampling signals by controlling the sampling frequency of the current sampling signals and determines the current parameters of the motor based on the multiple current sampling signals.

[0037] In one embodiment, the power module further includes:

[0038] A drive circuit 40, wherein a controlled end of the drive circuit 40 is connected to the main control circuit 30, an input end of the drive circuit 40 is connected to an output end of the current acquisition circuit 20, and an output end of the drive circuit 40 is connected to an input end of the motor;

[0039] The driving circuit 40 is configured to receive the PWM signal from the main control circuit 30 and switch on / off the path between the current acquisition circuit 20 and the motor according to the PWM signal, so as to adjust the current of the motor.

[0040] It will be appreciated that in this embodiment, the power module further includes a drive circuit 40. The drive circuit 40 is primarily used to drive the motor and regulate the motor's current and power by receiving the PWM signal output by the main control circuit 30, thereby maintaining a stable and stable operating state. Specifically, the drive circuit 40 receives the PWM signal output by the main control circuit 30 and, based on the level of the PWM signal, opens and closes the path between the current acquisition circuit 20 and the motor. For example, when the PWM signal is in a high-level state, the path between the current acquisition circuit 20 and the motor is opened; when the PWM signal is in a low-level state, the path between the current acquisition circuit 20 and the motor is closed. When the path between the current acquisition circuit 20 and the motor is open, the power processing circuit 10, sampling resistor R1, drive circuit 40, and motor form a closed loop, preventing current from being output to the motor through the power processing circuit 10, sampling resistor R1, and drive circuit 40. When the path between the current acquisition circuit 20 and the motor is closed, the power processing circuit 10, sampling resistor R1, drive circuit 40, and motor form a closed loop, preventing current from being output to the motor through the power processing circuit 10, sampling resistor R1, and drive circuit 40. Thus, by opening and closing the path between the current acquisition circuit 20 and the motor, the frequency of the output motor current can be adjusted, thereby achieving motor current regulation.

[0041] In one embodiment, the driving circuit 40 includes:

[0042] a first switching transistor, wherein the input end of the first switching transistor is the input end of the driving circuit 40 , the input end of the first switching transistor is connected to the controlled end of the first switching transistor, and the output end of the first switching transistor is the output end of the driving circuit 40 ;

[0043] a second switch tube, wherein an input end of the second switch tube is connected to a controlled end of the first switch tube, the controlled end of the second switch tube is a controlled end of the drive circuit 40, and an output end of the second switch tube is connected to a ground end;

[0044] The second switch tube is used to receive the PWM signal of the main control circuit 30 and switch on / off the path between the current acquisition circuit 20 and the ground terminal according to the PWM signal;

[0045] The first switch tube is used to connect the path between the current collection circuit 20 and the motor when the path between the current collection circuit 20 and the ground terminal is connected.

[0046] It is understood that in this embodiment, the first switching tube is implemented by sampling the bidirectional thyristor Q1, and the second switching tube is implemented by the first transistor Q2. The connection point of the sampling resistor R1 and the voltage divider resistor R2 is connected to the input terminal of the bidirectional thyristor Q1 and the controlled terminal of the bidirectional thyristor Q1, respectively. In actual application, the main control circuit 30 collects the current of the motor through the connection point of the sampling resistor R1 and the voltage divider resistor R2, and detects whether the operating state of the motor is abnormal based on the current of the motor, and outputs a PWM signal based on the detection result to further adjust the speed of the motor. The first transistor Q2 receives the PWM signal from the main control circuit 30, and when it is determined to be in a high level state based on the level state of the PWM signal, it turns on the path between the connection point of the sampling resistor R1 and the voltage divider resistor R2 and the ground terminal. At this point, current is output from the connection point between the sampling resistor R1 and the voltage-dividing resistor R2 to the input and controlled terminals of the bidirectional thyristor Q1. The bidirectional thyristor Q1 then conducts a path between the connection point between the sampling resistor R1 and the voltage-dividing resistor R2 and the motor, forming a closed loop among the power processing circuit 10, the sampling resistor R1, the bidirectional thyristor Q1, and the motor. Current is output to the motor through the power processing circuit 10, the sampling resistor R1, the bidirectional thyristor Q1, and the motor. Furthermore, when the first transistor Q2 determines that the level of the PWM signal is low, it disconnects the path between the connection point between the sampling resistor R1 and the voltage-dividing resistor R2 and the ground terminal. At this point, no current is output from the connection point between the sampling resistor R1 and the voltage-dividing resistor R2 to the bidirectional thyristor Q1. The bidirectional thyristor Q1 disconnects the path between the connection point between the sampling resistor R1 and the voltage-dividing resistor R2 and the motor. Consequently, the power processing circuit 10, the sampling resistor R1, the bidirectional thyristor Q1, and the motor fail to form a closed loop, and current cannot be output to the motor through the power processing circuit 10, the sampling resistor R1, and the bidirectional thyristor Q1. Therefore, by turning on / off the bidirectional thyristor Q1, the frequency of the output motor current can be adjusted, thereby achieving current regulation of the motor.

[0047] It should be understood that when the first transistor Q2 and the bidirectional thyristor Q1 are in the on state, the power processing circuit 10, the sampling resistor R1, the bidirectional thyristor Q1, and the motor form a closed loop, allowing the sampling resistor R1 to collect the electrical energy output by the power processing circuit 10. When the first transistor Q2 and the bidirectional thyristor Q1 are in the off state, the power processing circuit 10, the sampling resistor R1, the bidirectional thyristor Q1, and the motor cannot form a closed loop, resulting in the current collected by the sampling resistor R1 being zero. The main control circuit 30 collects the current signal processed by the sampling resistor R1 and the voltage divider resistor R2 and obtains the corresponding current parameters based on the current collection signal.

[0048] In one embodiment, the power processing circuit 10 includes:

[0049] The filter circuit 11, the input end of the voltage stabilizing circuit 12 is used to connect to the input end of the motor; the filter circuit 11 is used to filter the voltage of the working power supply of the motor and output a corresponding filter signal.

[0050] It will be appreciated that, in this embodiment, the filter circuit 11 is implemented using a first capacitor C1, a second capacitor C2, a third capacitor C3, and a filter resistor R4. The first capacitor C1, the second capacitor C2, and the third capacitor C3 achieve a filtering function through their energy storage and charge-discharge characteristics. For example, when the power supply voltage is higher than the voltage of the first capacitor C1, the second capacitor C2, and the third capacitor C3, the first capacitor C1, the second capacitor C2, and the third capacitor C3 charge; when the power supply voltage is lower than the voltage of the first capacitor C1, the second capacitor C2, and the third capacitor C3, the first capacitor C1, the second capacitor C2, and the third capacitor C3 discharge. The charge and discharge process of the first capacitor C1, the second capacitor C2, and the third capacitor C3 helps stabilize the voltage output by the motor, thereby reducing the fluctuation amplitude of the motor voltage and making the output voltage smoother. After being filtered by the first capacitor C1, the second capacitor C2, the third capacitor C3, and the filter resistor R4, the corresponding filtered signal is output to the voltage stabilization circuit 12 to further achieve voltage stabilization.

[0051] In one embodiment, the power processing circuit 10 further includes:

[0052] A voltage stabilizing circuit 12, wherein the input end of the voltage stabilizing circuit 12 is connected to the output end of the filter circuit 11, and the output end of the voltage stabilizing circuit 12 is connected to the input end of the current acquisition circuit 20;

[0053] The voltage stabilizing circuit 12 is used to stabilize the voltage of the filtered signal and then output a corresponding voltage signal to the current acquisition circuit 20 .

[0054] It will be appreciated that in this embodiment, the voltage stabilization circuit 12 is implemented using a Zener diode A7, a sixth resistor R6, an eighth resistor R8, and a ninth resistor R9. The Zener diode A7 has a PN junction. When the PN junction of the Zener diode A7 is in a reverse breakdown state, the Zener diode A7 is not damaged. The breakdown characteristics of the Zener diode A7 can be utilized to achieve voltage stabilization. For example, when the reverse voltage reaches the regulated value, the reverse current increases sharply. As long as the reverse current does not exceed the maximum allowable current, normal operation can be achieved. This allows the Zener diode A7 to maintain a substantially constant voltage across its terminals despite voltage changes, thereby achieving a voltage stabilization function and ensuring a stable operating voltage for subsequent circuits. After the Zener diode A7 stabilizes the voltage of the filter circuit 11, it outputs the voltage as a voltage signal to the sampling resistor R1 and the voltage divider resistor R2 in the current acquisition circuit 20.

[0055] In one embodiment, the power processing circuit 10 further includes:

[0056] The rectifier circuit 13 has an input end connected to the output end of the voltage stabilizing circuit 12 ; the rectifier circuit 13 is configured to perform AC-DC conversion on the voltage of the voltage signal and output a corresponding DC signal.

[0057] It is understandable that in this embodiment, the rectifier circuit 13 is implemented using a rectifier diode M7 and a twelfth resistor R12. The working principle of the rectifier diode M7 is based on its unidirectional conductive properties, which allows only forward current to pass through in an AC signal, while preventing reverse current from passing through. Specifically, when the forward voltage of the rectifier diode M7 exceeds its threshold voltage, the rectifier diode M7 enters a conducting state, allowing current to pass through; conversely, when the reverse voltage is greater than its threshold voltage, the rectifier diode M7 enters a cutoff state, and current cannot pass through. This characteristic enables the rectifier diode M7 to play a role in the rectifier circuit 13. The rectifier diode M7 converts the voltage of the voltage signal from AC to DC to convert AC into DC, thereby providing a stable DC power supply to other circuits.

[0058] In one embodiment, the power processing circuit 10 further includes:

[0059] an overcurrent protection circuit 50, wherein a controlled terminal of the overcurrent protection circuit 50 is connected to the output terminal of the rectifier circuit 13, an input terminal of the overcurrent protection circuit 50 is used to connect to a power supply terminal, and a connection point between the input terminal of the overcurrent protection circuit 50 and the power supply terminal is used to connect to the main control circuit 30, and an output terminal of the overcurrent protection circuit 50 is used to connect to a ground terminal;

[0060] The overcurrent protection circuit 50 is used to disconnect the path between the power supply terminal and the ground terminal when the current of the rectifier circuit 13 exceeds a preset current, and output a shutdown signal to the main control circuit 30.

[0061] It will be appreciated that in this embodiment, the overcurrent protection circuit 50 is implemented using the eleventh resistor R11, the thirteenth resistor R13, the fourteenth resistor R14, and the second transistor Q3. The controlled terminal of the second transistor Q3 is connected to the output terminal of the rectifier circuit 13, the input terminal of the second transistor Q3 is connected to the power supply terminal VCC, and the connection point between the input terminal of the second transistor Q3 and the power supply terminal VCC is connected to the main control circuit 30. The output terminal of the second transistor Q3 is connected to the ground terminal. In actual application, when the current output by the rectifier circuit 13 exceeds the preset current, the controlled terminal of the second transistor Q3 receives the larger current, damaging the second transistor Q3 and turning it off, thereby shutting off the path between the power supply terminal and the ground terminal. At this point, the current from the power supply terminal VCC cannot flow through the second transistor Q3, and no current flows through the connection point between the input terminal of the second transistor Q3 and the power supply terminal VCC, and a shutdown signal is output to the main control circuit 30. When receiving the shutdown signal, the main control circuit 30 detects that an overcurrent phenomenon is currently occurring, that is, the current of the current motor is too large, and the main control circuit 30 controls the current of the motor to be disconnected by outputting a control signal.

[0062] In one embodiment, the power processing circuit 10 further includes:

[0063] A load interface LIN, wherein the input end of the load interface LIN is used to connect to the motor, and the output end of the load interface LIN is connected to the input end of the filter circuit 11; the load interface LIN is used to establish a connection relationship between the filter circuit 11 and the motor.

[0064] It will be appreciated that, in this embodiment, the power processing circuit 10 also includes a zero-crossing detection circuit, which is disposed between the motor and the load interface LIN. The zero-crossing detection circuit is used to detect the zero points of the motor's AC power signal, accurately mark these zero points with pulse signals, and output the marked zero points to the load interface LIN in the form of working power. The load interface LIN transmits the incoming working power to the power processing circuit 10, which processes the working power and outputs the corresponding electrical energy to the current acquisition circuit 20 and other circuits.

[0065] The above embodiments are only preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A power module, characterized in that: The power module includes: A power processing circuit, wherein the input end of the power processing circuit is connected to the output end of the motor; the power processing circuit is used to process the working power of the motor and output corresponding electric energy; a current acquisition circuit, wherein the input end of the current acquisition circuit is connected to the output end of the power processing circuit, and the first output end of the current acquisition circuit is used to connect to the input end of the motor; the current acquisition circuit is used to collect electric energy output by the power processing circuit and output a corresponding current acquisition signal based on the electric energy; A main control circuit, wherein the input end of the main control circuit is connected to the second output end of the current acquisition circuit; the main control circuit is used to determine the current parameters of the motor according to the current acquisition signal of the current acquisition circuit.

2. The power module according to claim 1, wherein: The current acquisition circuit includes: Sampling resistor and voltage divider resistor; The first end of the sampling resistor is the input end of the current acquisition circuit, the second end of the sampling resistor is connected to the first end of the voltage divider resistor, the connection point between the sampling resistor and the voltage divider resistor is the first output end of the current acquisition circuit, and the second end of the voltage divider resistor is the second output end of the current acquisition circuit.

3. The power module according to claim 1, wherein: The power module further includes: A drive circuit, wherein a controlled end of the drive circuit is used to connect to the main control circuit, an input end of the drive circuit is connected to an output end of the current acquisition circuit, and an output end of the drive circuit is connected to an input end of the motor; The driving circuit is used to receive the PWM signal of the main control circuit and open / close the path between the current acquisition circuit and the motor according to the PWM signal to adjust the current of the motor.

4. The power module according to claim 3, wherein: The driving circuit includes: a first switching tube, wherein an input end of the first switching tube is an input end of the driving circuit, the input end of the first switching tube is connected to a controlled end of the first switching tube, and an output end of the first switching tube is an output end of the driving circuit; a second switching tube, wherein an input end of the second switching tube is connected to a controlled end of the first switching tube, the controlled end of the second switching tube is a controlled end of the driving circuit, and an output end of the second switching tube is used to be connected to a ground end; The second switch tube is used to receive the PWM signal of the main control circuit and switch on / off the path between the current acquisition circuit and the ground terminal according to the PWM signal; The first switching tube is used to connect the path between the current collection circuit and the motor when the path between the current collection circuit and the ground terminal is connected.

5. The power module according to claim 1, wherein: The power processing circuit includes: The filter circuit has an input end connected to an input end of the motor; the filter circuit is used to filter the voltage of the working power supply of the motor and output a corresponding filter signal.

6. The power module according to claim 5, wherein: The power processing circuit further includes: a voltage stabilizing circuit, wherein an input end of the voltage stabilizing circuit is connected to an output end of the filter circuit, and an output end of the voltage stabilizing circuit is connected to an input end of the current acquisition circuit; The voltage stabilizing circuit is used to stabilize the voltage of the filtered signal and then output a corresponding voltage signal to the current acquisition circuit.

7. The power module according to claim 6, wherein: The power processing circuit further includes: A rectifier circuit, wherein the input end of the rectifier circuit is connected to the output end of the voltage stabilizing circuit; the rectifier circuit is used to perform AC-DC conversion on the voltage of the voltage signal and then output a corresponding DC signal.

8. The power module according to claim 7, wherein: The power processing circuit further includes: an overcurrent protection circuit, wherein a controlled terminal of the overcurrent protection circuit is connected to the output terminal of the rectifier circuit, an input terminal of the overcurrent protection circuit is used to connect to a power supply terminal, and a connection point between the input terminal of the overcurrent protection circuit and the power supply terminal is used to connect to a main control circuit, and an output terminal of the overcurrent protection circuit is used to connect to a ground terminal; The overcurrent protection circuit is used to disconnect the path between the power supply end and the ground end when the current of the rectifier circuit exceeds a preset current, and output a shutdown signal to the main control circuit.

9. The power module according to claim 5, wherein: The power processing circuit further includes: A load interface, wherein the input end of the load interface is used to connect to the motor, and the output end of the load interface is connected to the input end of the filter circuit; the load interface is used to establish a connection relationship between the filter circuit and the motor.

10. An electric tool, characterized in that: The invention comprises an electric motor and a power module according to any one of claims 1 to 9.

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