A power tool firing depth adjustment method and system

Abstract

The application belongs to the technical field of electric tool firing depth adjustment, and specifically discloses an electric tool firing depth adjustment method and system, which comprises the following steps: obtaining a target firing depth parameter, searching for an initial control parameter set from a multi-dimensional parameter mapping table associated with workpiece hardness, battery state of charge and other working conditions; collecting multi-source signals in real time, calculating output torque, actual compression amount of an energy storage mechanism and the moment when a striking head contacts a workpiece; dynamically correcting the initial parameters based on the above data to generate a corrected control instruction; adjusting the power supply period of a driving motor and the activation timing of an electromagnetic brake, and synchronously monitoring the speed response to prevent abnormalities; comparing the depth deviation after a single firing, and updating the mapping table if the deviation exceeds a threshold. Through multi-source sensing, dynamic correction and self-learning optimization, the application solves the problems of poor adaptability and insufficient precision in the prior art, and improves the control stability and safety under complex working conditions.

Description

Technical Field

[0001] This invention belongs to the field of firing depth adjustment of electric striking tools, and relates to a method and system for adjusting firing depth of electric tools. Background Technology

[0002] Electric striking tools, as indispensable power equipment in construction, assembly, and maintenance operations, are widely used in processes requiring instantaneous high impact force, such as riveting, splicing, and punching. Their core function lies in using electrical energy to drive an internal energy storage mechanism, releasing kinetic energy in a very short time to complete a precise striking action on fasteners or workpieces. With the increasing demands of modern manufacturing for assembly precision, operational efficiency, and human-machine collaborative safety, electric striking tools not only need stable output performance but are also endowed with the ability to precisely control the striking depth to adapt to workpieces of different materials, thicknesses, and structural strengths. In this context, the controllability of striking depth has become a key technical indicator for measuring the intelligence and adaptability of such tools.

[0003] Under current technology, mainstream electric striking tools generally use mechanical limiters or stroke feedback control to adjust the striking depth. Traditional solutions often rely on adjustable mechanical stops or limit bolts located between the drive mechanism and the striking head. By manually turning these bolts to change their axial position, the maximum stroke of the striking piston is physically limited, indirectly controlling the striking depth. Some high-end models have introduced a closed-loop control system based on position sensors. This system monitors the displacement of the striking components in real time and dynamically adjusts the motor power supply timing or the timing of electromagnetic braking intervention based on preset parameters, aiming to achieve more precise depth control.

[0004] The above-mentioned solutions improve the flexibility of adjustment and the accuracy of repeatability to some extent. However, some inherent characteristics of the above-mentioned technical solutions at the principle level mean that they still have limitations.

[0005] On the one hand, mechanical adjustment methods cannot achieve dynamic self-adaptation during operation, making it difficult to meet the requirements of micron-level precision assembly. On the other hand, although sensor-dependent electronic control has the potential for high precision, its high hardware cost, weak anti-interference ability, and oversimplification of models result in insufficient dynamic response and poor environmental adaptability. Especially under non-calibrated working conditions, simply relying on preset strokes or fixed control parameters can easily lead to firing depth deviations, affecting assembly quality and even damaging the workpiece.

[0006] Therefore, without significantly increasing system complexity, constructing a firing depth adjustment method that integrates multi-source state perception, dynamic parameter correction, and self-learning optimization mechanisms to achieve high-precision, robust, and adaptive depth control has become a pressing technical challenge in this field. Summary of the Invention

[0007] Therefore, the present invention aims to provide a method and system for adjusting the firing depth of power tools. By monitoring the output torque and the dynamics of the striking head in real time, and correcting key control parameters online according to a preset algorithm, the method aims to improve the control accuracy and stability of the firing depth under different working conditions.

[0008] The objective of this invention can be achieved through the following technical solution: The first aspect of this invention provides a method for adjusting the firing depth of an electric tool, comprising:

[0009] Obtain the target firing depth parameter and retrieve the corresponding initial control parameter set from the preset multidimensional parameter mapping table, including the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, and the triggering sequence of the electromagnetic brake.

[0010] The current signal of the drive motor, the displacement signal of the energy storage mechanism, and the acceleration signal of the striking head are collected in real time. The current output torque is calculated to determine the actual compression of the energy storage mechanism and the contact time between the striking head and the workpiece.

[0011] Based on the current output torque, contact time, and actual compression, the initial control parameter set is dynamically corrected to generate the corrected control command.

[0012] The modified control command is sent to the drive motor controller and the electromagnetic brake controller to adjust the power supply cycle of the drive motor and the activation timing of the electromagnetic brake.

[0013] After a single firing action is completed, the actual firing depth feedback value is recorded, and the absolute value of the deviation is calculated by comparing it with the target firing depth parameter. If the absolute value of the deviation is greater than the preset tolerance threshold, the control parameter set for the corresponding working condition in the multidimensional parameter mapping table is updated.

[0014] A second aspect of the present invention provides a power tool firing depth adjustment system, comprising:

[0015] The parameter acquisition and retrieval module acquires the target firing depth parameter and retrieves the corresponding initial control parameter set from the preset multi-dimensional parameter mapping table, including the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, and the triggering sequence of the electromagnetic brake.

[0016] The multi-source state sensing module collects the current signal of the drive motor, the displacement signal of the energy storage mechanism, and the acceleration signal of the striking head in real time, calculates the current output torque, and determines the actual compression of the energy storage mechanism and the contact time between the striking head and the workpiece.

[0017] The dynamic parameter correction module dynamically corrects the initial control parameter set based on the current output torque, contact time, and actual compression, and generates the corrected control command.

[0018] The actuator correction module sends the corrected control commands to the drive motor controller and the electromagnetic brake controller to adjust the power supply cycle of the drive motor and the activation timing of the electromagnetic brake.

[0019] The feedback learning and optimization module records the actual firing depth feedback value after a single firing action is completed, compares it with the target firing depth parameter to calculate the absolute value of the deviation, and updates the control parameter set for the corresponding working condition in the multidimensional parameter mapping table if the absolute value of the deviation is greater than the preset tolerance threshold.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention introduces a dynamic parameter correction mechanism based on real-time torque and compression sensing, which can respond to load changes and help improve the energy consistency of firing action.

[0021] This invention designs actuator control logic that includes real-time speed tracking and emergency braking triggering. It can monitor online whether the drive motor response matches the theoretical trajectory and terminate the action in time when the energy output is abnormal. This prevents loss of firing depth, workpiece damage or tool jamming caused by insufficient or excessive energy, and enhances the robustness and safety of the system.

[0022] By introducing a feedback learning and optimization mechanism, this invention can continuously iterate and update the multi-dimensional parameter mapping table, enabling the system to have self-learning and self-adaptive capabilities, continuously optimize control performance under non-calibrated operating conditions, and reduce the dependence on preset parameters for long-term use. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the 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.

[0024] Figure 1 This is a schematic diagram of the method steps of the present invention.

[0025] Figure 2 This is a schematic diagram of the system module connections of the present invention.

[0026] Figure 3 This is a flowchart illustrating the logic flow for generating the initial control parameter set of this invention.

[0027] Figure 4 This is a logical flowchart of the feedback learning and parameter optimization mechanism in this invention. Detailed Implementation

[0028] 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.

[0029] Please see Figure 1 As shown, the first aspect of the present invention provides a method for adjusting the firing depth of a power tool, the specific steps of which are as follows:

[0030] Obtain the target firing depth parameter and retrieve the corresponding initial control parameter set from the preset multidimensional parameter mapping table, including the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, and the triggering sequence of the electromagnetic brake.

[0031] For a preferred embodiment of the present invention, please refer to Figure 3 As shown, the specific steps for retrieving the corresponding initial control parameter set are as follows:

[0032] Receive the target firing depth parameter input by the user and verify whether the target firing depth parameter is within the allowable range of the physical stroke of the electric striking tool.

[0033] It should be noted that verifying whether the target firing depth parameter is within the allowable range of the electric striking tool's physical stroke is to ensure operational safety, equipment integrity, and operational effectiveness. The tool's mechanical structure has minimum and maximum stroke limits; exceeding these limits can cause problems: exceeding the maximum stroke may lead to motor overload, mechanical component jamming, or breakage; falling below the minimum safe stroke can easily result in dry firing, tool rebound, and other abnormalities. Simultaneously, this verification eliminates unachievable parameters, preventing invalid firing or workpiece damage due to parameter inaccuracies. It lays the foundation for subsequent retrieval of initial control parameters and precise adjustment of the firing depth, serving as a crucial preliminary step to ensure a compliant and orderly adjustment process.

[0034] If it is within the allowable range, the multidimensional parameter mapping table is queried according to the target firing depth parameter. The multidimensional parameter mapping table uses firing depth as the index dimension and stores control parameter combinations under different workpiece hardness grades, battery state of charge and ambient temperature conditions.

[0035] Select the combination of control parameters that matches the current operating conditions as the initial control parameter set.

[0036] It should be noted that the criteria for matching the current working condition are as follows: when a combination of control parameters stored in the multidimensional parameter mapping table has a firing depth dimension that is consistent with the target firing depth parameter set by the user, and the corresponding workpiece hardness grade, battery state of charge range, and ambient temperature range are completely consistent with the actual workpiece hardness, the current battery state of charge of the tool, and the ambient temperature of the operation, respectively, then the combination of control parameters can be determined to match the current working condition.

[0037] If no working condition combination matching the current working condition is found, an interpolation method is used to generate approximate control parameters between adjacent working condition points, and these approximate control parameters are used as the initial control parameter set for this firing action.

[0038] Furthermore, the method for generating approximate control parameters is as follows: based on the two sets of adjacent working condition points that are closest to each dimension of the current working condition in the multidimensional parameter mapping table, the control parameters such as the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, and the triggering sequence of the electromagnetic brake corresponding to these two sets of working condition points are extracted, and a set of intermediate values ​​is calculated based on the interpolation method. These intermediate values ​​are the approximate control parameters adapted to this firing action and are used as the initial control parameter set.

[0039] In a preferred embodiment of the present invention, the specific construction process of the multidimensional parameter mapping table is as follows:

[0040] When using the electric striking tool for the first time, the calibration mode is executed. In this mode, multiple standard firing depth values ​​are set sequentially, and for each standard firing depth value, multiple firing experiments are conducted under a variety of preset typical working condition combinations. The typical working condition combinations include test workpieces with different hardness levels, different battery state of charge ranges, and different ambient temperature ranges.

[0041] It should be noted that the preset tolerance threshold is set based on the following criteria: the depth control accuracy requirements required for the application scenarios of electric striking tools, the manufacturing tolerances of the tool's mechanical structure, the sensor sampling error, and the response error of the drive system, while also taking into account the firing stability under different working conditions. The maximum acceptable depth deviation in actual operation is used as the core benchmark, and the threshold is determined after multiple calibration experiments. This ensures that the selected set of control parameters can keep the deviation between the actual firing depth and the target value within the engineering allowable range, thus meeting the operational quality requirements while avoiding insufficient selection of effective parameter sets due to overly strict thresholds.

[0042] During each firing experiment, the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, the triggering sequence of the electromagnetic brake, and the actual firing depth feedback value were recorded simultaneously.

[0043] Cluster analysis was performed on the control parameters required to achieve the target firing depth under each combination of working conditions to select a set of control parameters that ensures the absolute value of the deviation between the actual firing depth feedback value and the target firing depth is less than a preset tolerance threshold.

[0044] The selected set of control parameters is structured and stored according to the corresponding firing depth, workpiece hardness grade, battery state of charge and ambient temperature to form an initial multidimensional parameter mapping table.

[0045] During subsequent use, the control parameter set for the corresponding operating condition in the multidimensional parameter mapping table is updated synchronously.

[0046] It should be noted that the purpose of retrieving the corresponding initial control parameter set is as follows: the firing depth is affected by multiple parameters, including the drive motor speed, the pre-compression of the energy storage mechanism, and the triggering sequence of the electromagnetic brake. Furthermore, these parameters need to be adapted to complex operating conditions such as the target firing depth, workpiece hardness, battery state of charge, and ambient temperature. A pre-set multi-dimensional parameter mapping table stores calibrated and verified combinations of suitable parameters. Retrieving this set directly provides a basic control basis that fits the current operating conditions, avoiding firing depth deviations caused by blindly setting parameters. Simultaneously, it provides a reliable benchmark for subsequent dynamic correction based on real-time signals, ensuring efficient and precise initiation of the adjustment process.

[0047] The current signal of the drive motor, the displacement signal of the energy storage mechanism, and the acceleration signal of the striking head are collected in real time. The current output torque is calculated to determine the actual compression of the energy storage mechanism and the contact time between the striking head and the workpiece.

[0048] It is important to explain the purpose of calculating the current output torque, determining the actual compression of the energy storage mechanism, and the contact moment between the striking head and the workpiece: The current output torque reflects the energy output state of the drive motor, and by comparing it with a standard torque curve, the impact of load changes on the firing energy can be assessed; the actual compression of the energy storage mechanism is directly related to the stored energy, and the difference between it and the pre-compression threshold can clarify the energy deviation; the contact moment between the striking head and the workpiece is a key node for dividing the effective work phase. These three factors together provide real-time basis for dynamically correcting initial control parameters, adjusting the motor acceleration slope and the electromagnetic brake triggering sequence, ensuring that the energy output adapts to the current working conditions, avoiding firing depth deviations caused by parameter inaccuracies, and guaranteeing adjustment accuracy and operational stability.

[0049] In a preferred embodiment of the present invention, the specific steps for calculating the current output torque and determining the actual compression of the energy storage mechanism and the contact time between the striking head and the workpiece are as follows:

[0050] The current signal of the drive motor is acquired by a current sensor at a sampling frequency no lower than a preset first sampling frequency, and the current output torque is calculated based on the current signal and the motor back electromotive force model.

[0051] The actual compression amount of the energy storage mechanism is determined by monitoring the compression displacement of the elastic element in the energy storage mechanism with a displacement sensor at a second sampling frequency not lower than a preset value.

[0052] Acceleration timing data of the striking head is collected by a pre-installed accelerometer at a third sampling frequency no less than the preset one, and the contact moment between the striking head and the workpiece is identified based on the amplitude and duration of the sudden change in the acceleration signal.

[0053] Furthermore, by analyzing the accelerometer signal, if a sudden change in the acceleration value is detected that exceeds a preset threshold, and this sudden change continues for more than a preset time threshold, it is determined to be the moment of contact.

[0054] The current output torque, the actual compression of the energy storage mechanism, and the contact time between the striking head and the workpiece are timestamped and then input to the control unit.

[0055] It should be noted that the purpose of using different sampling frequencies is to adapt to the characteristics and adjustment requirements of the three types of signals, ensuring the accuracy and practicality of data acquisition. The drive motor current signal changes rapidly, requiring a higher first sampling frequency to accurately calculate the output torque; the compression displacement of the energy storage mechanism changes relatively smoothly, and a suitable second sampling frequency is sufficient to accurately obtain the actual compression amount; the impact head acceleration signal needs to capture the abrupt changes at the moment of contact, requiring a sufficient third sampling frequency to ensure that the contact moment is not missed. Setting different sampling frequencies avoids signal distortion or resource waste caused by a single frequency, and provides high-quality, multi-source data support that adapts to the requirements for subsequent parameter correction.

[0056] Preferably, the settings of the first, second, and third sampling frequencies need to be determined comprehensively based on signal characteristics, adjustment accuracy, and hardware computing power: referring to the rapid change characteristics of motor current signals and the accuracy requirements of torque calculation, the first sampling frequency is set to 1-2kHz; based on the smooth characteristics of the displacement signal of the energy storage mechanism, the second sampling frequency is set to 100-500Hz; according to the requirements for capturing sudden changes in the acceleration signal of the impact head and following the Nyquist sampling theorem, the third sampling frequency is set to 2-5kHz, and all three need to be verified by calibration experiments to match the upper limit of hardware computing power while meeting data accuracy requirements and avoiding sampling overload.

[0057] Based on the current output torque, the contact time, and the actual compression, the initial control parameter set is dynamically corrected to generate the corrected control command.

[0058] In a preferred embodiment of the present invention, the specific steps for generating the modified control command are as follows:

[0059] The starting point for the striking head to enter the effective work phase is determined based on the contact time.

[0060] It should be noted that the determination of the effective work phase is based on the contact moment between the striking head and the workpiece: the acceleration timing data of the striking head is collected by an accelerometer at a preset third sampling frequency. When a sudden change in the acceleration signal that meets the preset threshold amplitude and the duration meets the judgment criteria is detected, the moment can be identified as the contact moment between the striking head and the workpiece. With this contact moment as the dividing point, before which the striking head is in the no-load idle stroke stage, the striking head begins to contact the workpiece and transmit impact force. This contact moment is defined as the start time of the effective work phase. The subsequent striking energy will directly act on the workpiece to achieve the target striking depth.

[0061] The energy storage deviation is calculated based on the difference between the actual compression amount and the pre-compression threshold.

[0062] Based on the degree of deviation between the current output torque and the standard torque curve, the influence coefficient of load change on firing energy is evaluated.

[0063] It should be noted that a standard torque-speed curve database is established during the calibration phase. This database contains the theoretical torque output trajectory of the drive motor during the acceleration phase under no-load and different standard load conditions. During firing, the current output torque, calculated in real time based on the motor current signal and the back EMF model, is compared point by point with the standard torque value in the database at the corresponding speed. The relative deviation rate between the two is calculated at each point, and then the relative deviation rate is integrated to quantify the overall deviation of the torque output from the standard curve under the current operating condition. This provides a core basis for the subsequent evaluation of the impact coefficient of load changes on firing energy.

[0064] By combining the energy storage deviation and the influence coefficient, the acceleration slope parameter of the drive motor is adjusted to compensate for the energy output deviation.

[0065] It should be noted that the method for adjusting the acceleration slope parameter of the drive motor is as follows: the energy storage deviation is calculated by the difference between the actual compression amount of the energy storage mechanism and the preset compression threshold; then, the influence coefficient of the load change on the firing energy is quantified by integrating the relative deviation rate of the current output torque and the standard torque curve point by point; subsequently, the energy storage deviation and the influence coefficient are weighted and fused according to preset weights. If the fusion result shows that the energy output is insufficient, the acceleration slope parameter is increased to improve the energy supply rate of the motor; if the energy output is excessive, the acceleration slope parameter is decreased to reduce the energy supply. This dynamic adjustment achieves precise compensation for the energy output deviation.

[0066] Furthermore, by weighting and fusing the energy storage deviation and load influence coefficient according to preset weights, a comprehensive energy demand deviation value is obtained. If this value is positive, it indicates that the current energy storage is insufficient or the load resistance is increased, resulting in the actual energy output failing to meet the target firing requirement. If this value is negative, it indicates that the energy output is excessive or the load resistance is reduced, posing a risk of overshoot in firing depth. Based on this, dynamic adjustments are made according to a preset deviation-slope adjustment coefficient mapping relationship: when the fusion result is positive, the acceleration slope parameter is increased proportionally to the deviation value, increasing the rate of change of the motor voltage duty cycle, thereby accelerating the energy supply rhythm and compensating for energy losses caused by insufficient energy storage or load. When the fusion result is negative, the acceleration slope parameter is decreased proportionally, slowing down the increase rate of the voltage duty cycle and reducing the motor energy output rate to avoid excessive energy leading to overshoot. If the fusion result is within a preset small deviation range, the original acceleration slope parameter is maintained unchanged to ensure the stability of energy output. The entire adjustment process is based on real-time operating data, achieving precise matching between energy output and actual demand through quantitative proportional adjustment.

[0067] Based on the adjusted acceleration slope parameters and the starting time point, the optimal triggering sequence of the electromagnetic brake is recalculated, and a corrected control command containing the updated acceleration slope parameters and the optimal triggering sequence is generated.

[0068] In a preferred embodiment of the present invention, the specific steps for evaluating the influence coefficient of load change on firing energy are as follows:

[0069] A standard torque-speed curve database is established in advance during the calibration phase. The database contains the theoretical torque output trajectory of the drive motor during the acceleration phase under no-load and different standard load conditions.

[0070] It should be noted that the calibration process of the standard torque-speed curve database is as follows: First, a bench test system including a high-precision dynamometer, a dynamic torque sensor, and a high-speed data acquisition card is built; then, the electric impact tool is fixed, and the drive motor is controlled to run in the acceleration phase under no-load and gradually increasing standard load conditions; the motor current, voltage, real-time speed, and output torque data are collected synchronously using sensors; the theoretical torque value corresponding to each speed point is calculated by combining the motor back electromotive force model, abnormal noise points are eliminated, and a smooth curve is fitted; finally, these theoretical torque output trajectories representing different load characteristics are stored in the memory to form the standard torque-speed curve database.

[0071] During the firing action, the current output torque calculated in real time is compared point by point with the standard torque value at the corresponding speed, and the relative deviation rate between the two is calculated.

[0072] Based on the integral value of the relative deviation rate, the degree of suppression of the load on the motor energy output under the current operating condition is quantified, and the load influence coefficient is obtained.

[0073] Preferably, the degree of suppression is mapped to a load influence coefficient between 0.8 and 1.2, where 1.0 indicates no load deviation, less than 1.0 indicates that the load resistance increases, resulting in insufficient energy output, and greater than 1.0 indicates that the load resistance decreases, resulting in excessive energy output.

[0074] The load impact coefficient is weighted and integrated with the energy storage deviation.

[0075] It should be noted that the weighting is based on a comprehensive consideration of the mechanical characteristics and energy transfer laws of the electric striking tool, and is determined according to the actual contribution of the stored energy deviation and the load influence coefficient to the final firing depth and response sensitivity. Typically, the stored energy deviation is given a higher weight, as it directly determines the upper limit of work done in a single firing. The weighting of the load influence coefficient is set based on the hysteresis characteristics of the motor output to load changes and correlation analysis in historical calibration data, ensuring that the weighted fusion of the two accurately reflects the actual energy demand under the current operating conditions, avoiding overshoot or insufficient compensation caused by adjusting a single parameter.

[0076] The modified control command is sent to the drive motor controller and the electromagnetic brake controller to adjust the power supply cycle of the drive motor and the activation timing of the electromagnetic brake.

[0077] In a preferred embodiment of the present invention, the specific steps for adjusting the power supply cycle of the drive motor and the activation timing of the electromagnetic brake are as follows:

[0078] The modified control command is analyzed, and the acceleration slope parameter and optimal trigger timing are extracted.

[0079] A pulse width modulation signal configuration command containing the acceleration slope parameter is sent to the drive motor controller to dynamically adjust the voltage duty cycle of the drive motor.

[0080] A timing control signal containing the optimal trigger timing is sent synchronously to the electromagnetic brake controller, so that the electromagnetic brake is activated within a preset time window before the striking head reaches the target stroke position.

[0081] Monitor whether the actual speed response of the drive motor matches the theoretical speed trajectory corresponding to the acceleration slope parameter.

[0082] It should be noted that the method for determining whether the actual speed response matches the theoretical speed trajectory is as follows: taking the start time of the drive motor as the zero point of time, the real-time collected actual speed data is dynamically compared with the theoretical speed trajectory derived from the acceleration slope parameters at each moment; the speed deviation value of the two at the same time node is calculated. If the absolute value of the deviation value is always less than the preset speed deviation threshold throughout the entire acceleration phase, and the trend of the actual speed change is consistent with the theoretical trajectory, then it is determined to be a match; if there is a continuous deviation exceeding the limit or a trend deviation, it is determined to be a mismatch, and subsequent parameter correction or fault protection mechanisms need to be triggered.

[0083] If the actual speed response lags behind the theoretical speed trajectory by more than a set threshold, an emergency braking signal is triggered to activate the electromagnetic brake in advance to terminate the firing action.

[0084] It should be noted that the reason for triggering emergency braking and activating the electromagnetic brake in advance is that the actual speed response lags significantly behind the theoretical trajectory, meaning that the drive motor cannot reach the energy level required for the preset compression within the specified time, causing the energy storage mechanism to fail to complete effective energy storage. Forcing firing may not only fail to achieve the target firing depth, resulting in operation failure, but may also cause the tool to jam or parts to be damaged due to insufficient energy. Therefore, the operation must be terminated immediately to ensure equipment safety.

[0085] In a preferred embodiment of the present invention, the specific steps for monitoring whether the actual speed response of the drive motor matches the theoretical speed trajectory corresponding to the acceleration slope parameter are as follows:

[0086] After sending a pulse width modulation signal configuration command containing acceleration slope parameters, the speed tracking unit is activated. This unit obtains the actual speed of the drive motor at a frequency not lower than the preset execution frequency based on encoder or back EMF estimation.

[0087] The actual rotational speed is compared in real time with the theoretical rotational speed trajectory derived from the acceleration slope parameter, and the rotational speed deviation between the two is calculated in each control cycle.

[0088] If the speed deviation value exceeds the preset speed tolerance threshold for three consecutive control cycles, it is determined that the actual speed response is lagging.

[0089] It should be noted that the speed tolerance threshold is set based on the following: taking into account the mechanical friction fluctuations of the drive motor during actual operation, the inherent noise of current sampling, and the minor impact of battery voltage fluctuations on the speed, an allowable normal fluctuation range is set. The purpose is to filter out random errors from single sampling, avoid misjudgments due to instantaneous interference, and ensure that when the speed deviation exceeds this range for three consecutive control cycles, the true lag phenomenon caused by load abnormalities or system faults can be accurately identified, thus ensuring both accuracy and system robustness.

[0090] The rotational speed tolerance threshold is dynamically adjusted based on the current battery voltage state. When the battery voltage is lower than a preset percentage of the rated value, the tolerance threshold is relaxed.

[0091] It should be noted that when the battery voltage drops below a preset percentage of its rated value, the output power and torque capacity of the drive motor will naturally decrease due to insufficient power supply, inevitably causing the actual speed response to lag behind the standard theoretical trajectory. If a strict speed tolerance threshold is maintained at this time, the system is highly prone to misjudgment and triggering unnecessary emergency braking. Therefore, to adapt to the physical characteristics of the battery under low power conditions and ensure that the tool can still maintain basic operating capabilities in low power mode, the tolerance threshold needs to be adjusted proportionally according to the magnitude of the voltage drop, allowing for a larger speed deviation, thereby preventing false triggering and maintaining the continuous operation of the system.

[0092] It should be noted that the tolerance threshold is adjusted as follows: a mapping table between battery voltage and tolerance amplification factor is pre-established. When the battery voltage is detected to be lower than the preset percentage of the rated value, the system reads the current voltage value in real time and looks up the corresponding amplification factor in the table. Then, the factor is multiplied by the basic speed tolerance threshold to calculate the dynamic tolerance threshold adapted to the current low battery condition. This allows for a larger speed deviation without changing the core control logic, preventing false triggering caused by voltage drop.

[0093] When the actual speed response is determined to be lagging, an emergency braking signal is generated and sent to the electromagnetic brake controller to forcibly terminate the firing action.

[0094] After a single firing action is completed, the actual firing depth feedback value is recorded, and the absolute value of the deviation is calculated by comparing it with the target firing depth parameter. If the absolute value of the deviation is greater than the preset tolerance threshold, the control parameter set for the corresponding working condition in the multidimensional parameter mapping table is updated.

[0095] For a preferred embodiment of the present invention, please refer to Figure 4 As shown, the specific steps for updating the control parameter set under the corresponding operating condition in the multidimensional parameter mapping table are as follows:

[0096] The actual displacement relative to the reference plane after the impact is obtained by a displacement sensor, and this displacement is used as the actual impact depth feedback value.

[0097] The actual firing depth feedback value is compared with the target firing depth parameter, and the absolute deviation between the two is calculated.

[0098] Determine whether the absolute deviation value is greater than a preset tolerance threshold. If it is, extract the workpiece material type, ambient temperature data, and battery voltage status used in this firing process as working condition identification information.

[0099] It should be noted that the preset tolerance threshold is set based on a comprehensive consideration of the tool's inherent mechanical structure frequency, sensor noise level, and test data from a large number of typical operating conditions. For example, by analyzing hundreds of impact test data, it was determined that when the acceleration exceeds 5g and lasts for 2ms, contact events can be reliably identified with a false positive rate of less than 1%. Operators can fine-tune the threshold within ±20% of the above-mentioned baseline value in the system debugging interface, depending on the specific tool model and working environment.

[0100] Based on the operating condition identification information, the corresponding subset of control parameters is located in the multidimensional parameter mapping table.

[0101] The gradient descent algorithm is used to iteratively correct the target speed of the drive motor, the pre-compression threshold and the trigger timing in the subset of control parameters until the actual firing depth feedback value of the next firing action falls within the tolerance range. The corrected parameters are then written into a multi-dimensional parameter mapping table.

[0102] In a preferred embodiment of the present invention, a safety interlock mechanism is also provided, which performs the following operations during the firing depth adjustment process: after obtaining the target firing depth parameter, it verifies whether the parameter exceeds the maximum stroke limit or minimum safe stroke limit allowed by the tool's mechanical structure; if the target firing depth parameter is less than the minimum safe stroke limit, it is automatically corrected to the standard depth value corresponding to the minimum safe stroke, and a prompt message is issued to the user; during the firing action, if the impact head acceleration signal is detected to have no effective contact characteristics within a preset contact time window, it is determined to be an abnormal dry firing condition, the power supply to the drive motor is immediately interrupted, and the electromagnetic brake is activated; after a single firing is completed, if the actual firing depth feedback value is zero or negative, the action is marked as an invalid firing, and the update of the multidimensional parameter mapping table is prohibited to avoid polluting the parameter database due to abnormal data; all safety interlock judgments are executed in an independent safety monitoring coprocessor to ensure the safety of operators and equipment even if the main control unit fails.

[0103] Please see Figure 2 As shown, a second aspect of the present invention provides a power tool firing depth adjustment system, including a parameter acquisition and retrieval module, a multi-source state perception module, a dynamic parameter correction module, an actuator correction module, and a feedback learning and optimization module. The parameter acquisition and retrieval module is connected to the multi-source state perception module, the multi-source state perception module is connected to the dynamic parameter correction module, the dynamic parameter correction module is connected to the actuator correction module, the actuator correction module is connected to the feedback learning and optimization module, and the feedback learning and optimization module is connected to the parameter acquisition and retrieval module.

[0104] The parameter acquisition and retrieval module acquires the target firing depth parameter and retrieves the corresponding initial control parameter set from the preset multi-dimensional parameter mapping table, including the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, and the triggering sequence of the electromagnetic brake.

[0105] The multi-source state sensing module collects the current signal of the drive motor, the displacement signal of the energy storage mechanism, and the acceleration signal of the striking head in real time, calculates the current output torque, and determines the actual compression of the energy storage mechanism and the contact time between the striking head and the workpiece.

[0106] The dynamic parameter correction module dynamically corrects the initial control parameter set based on the current output torque, the contact time, and the actual compression, and generates the corrected control command.

[0107] The actuator correction module sends the corrected control commands to the drive motor controller and the electromagnetic brake controller to adjust the power supply cycle of the drive motor and the activation timing of the electromagnetic brake.

[0108] The feedback learning and optimization module records the actual firing depth feedback value after a single firing action is completed, compares it with the target firing depth parameter to calculate the absolute value of the deviation, and updates the control parameter set for the corresponding working condition in the multidimensional parameter mapping table if the absolute value of the deviation is greater than the preset tolerance threshold.

[0109] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined by the present invention, and all such modifications and additions should fall within the protection scope of the present invention.

Claims

1. A method for adjusting the firing depth of a power tool, characterized in that: include: Obtain the target firing depth parameter and retrieve the corresponding initial control parameter set from the preset multi-dimensional parameter mapping table, including the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, and the triggering sequence of the electromagnetic brake; The current signal of the drive motor, the displacement signal of the energy storage mechanism, and the acceleration signal of the striking head are collected in real time to calculate the current output torque and determine the actual compression of the energy storage mechanism and the contact time between the striking head and the workpiece. Based on the current output torque, contact time, and actual compression, the initial control parameter set is dynamically corrected to generate the corrected control command. The modified control command is sent to the drive motor controller and the electromagnetic brake controller to adjust the power supply cycle of the drive motor and the activation timing of the electromagnetic brake. After a single firing action is completed, the actual firing depth feedback value is recorded, and the absolute value of the deviation is calculated by comparing it with the target firing depth parameter. If the absolute value of the deviation is greater than the preset tolerance threshold, the control parameter set under the corresponding working condition in the multidimensional parameter mapping table is updated. The specific steps for calculating the current output torque and determining the actual compression of the energy storage mechanism and the contact moment between the striking head and the workpiece are as follows: The current signal of the drive motor is acquired by a current sensor at a sampling frequency no lower than a preset first sampling frequency, and the current output torque is calculated based on the current signal and the motor back electromotive force model. The actual compression amount of the energy storage mechanism is determined by monitoring the compression displacement of the elastic element in the energy storage mechanism with a displacement sensor at a second sampling frequency not lower than the preset one. Acceleration timing data of the striking head is collected by a pre-installed accelerometer at a third sampling frequency no less than the preset one, and the contact moment between the striking head and the workpiece is identified based on the amplitude and duration of the sudden change in the acceleration signal. The current output torque, the actual compression of the energy storage mechanism, and the contact time between the impact head and the workpiece are timestamped and then input to the control unit. The specific steps for generating the corrected control commands are as follows: The starting point for the striking head to enter the effective work phase is determined based on the contact time. The energy storage deviation is calculated based on the difference between the actual compression amount and the pre-compression threshold. Based on the degree of deviation between the current output torque and the standard torque curve, evaluate the impact coefficient of load change on firing energy; Based on the energy storage deviation and the influence coefficient, adjust the acceleration slope parameter of the drive motor; Based on the adjusted acceleration slope parameters and the starting time point, the optimal triggering sequence of the electromagnetic brake is recalculated, and a corrected control command containing the updated acceleration slope parameters and the optimal triggering sequence is generated.

2. The method for adjusting the firing depth of a power tool according to claim 1, characterized in that: The specific steps for retrieving the corresponding initial control parameter set are as follows: Receive the target firing depth parameter input by the user and verify whether the target firing depth parameter is within the allowable range of the physical stroke of the electric striking tool; If it is within the allowable range, the multidimensional parameter mapping table is queried according to the target firing depth parameter. The multidimensional parameter mapping table uses firing depth as the index dimension and stores control parameter combinations under different workpiece hardness grades, battery charge state and ambient temperature conditions. Select a combination of control parameters that matches the current operating conditions as the initial control parameter set; If no working condition combination matching the current working condition is found, an interpolation method is used to generate approximate control parameters between adjacent working condition points, and these approximate control parameters are used as the initial control parameter set for this firing action.

3. The method for adjusting the firing depth of a power tool according to claim 1, characterized in that: The specific steps for evaluating the impact coefficient of load variation on firing energy are as follows: A standard torque-speed curve database is established in advance during the calibration phase. The database contains the theoretical torque output trajectory of the drive motor during the acceleration phase under no-load and different standard load conditions. During the firing action, the current output torque calculated in real time is compared with the standard torque value at the corresponding speed point by point, and the relative deviation rate between the two is calculated. Based on the integral value of the relative deviation rate, the degree of suppression of the load on the motor energy output under the current operating condition is quantified, and this degree of suppression is mapped to the influence coefficient of load change on the firing energy.

4. The method for adjusting the firing depth of a power tool according to claim 1, characterized in that: The specific steps for adjusting the power supply cycle of the drive motor and the activation timing of the electromagnetic brake are as follows: The corrected control command is analyzed, and the acceleration slope parameter and optimal trigger timing are extracted. Send a pulse width modulation signal configuration command containing the acceleration slope parameter to the drive motor controller to dynamically adjust the voltage duty cycle of the drive motor; A timing control signal containing the optimal trigger timing is sent synchronously to the electromagnetic brake controller, so that the electromagnetic brake is activated within a preset time window before the striking head reaches the target stroke position; Monitor whether the actual speed response of the drive motor matches the theoretical speed trajectory corresponding to the acceleration slope parameter; If the actual speed response lags behind the theoretical speed trajectory by more than a set threshold, an emergency braking signal is triggered to activate the electromagnetic brake in advance to terminate the firing action.

5. The method for adjusting the firing depth of a power tool according to claim 4, characterized in that: The specific steps for monitoring whether the actual speed response of the drive motor matches the theoretical speed trajectory corresponding to the acceleration slope parameter are as follows: After sending a pulse width modulation signal configuration command containing acceleration slope parameters, the speed tracking unit is activated. This unit obtains the actual speed of the drive motor at an execution frequency not lower than the preset frequency based on encoder or back EMF estimation. The actual speed is compared with the theoretical speed trajectory derived from the acceleration slope parameter in real time, and the speed deviation between the two in each control cycle is calculated. If the speed deviation value exceeds the preset speed tolerance threshold in three consecutive control cycles, it is determined that the actual speed response is lagging. The rotational speed tolerance threshold is dynamically adjusted according to the current battery voltage state. When the battery voltage is lower than a preset percentage of the rated value, the tolerance threshold is relaxed. When the actual speed response is determined to be lagging, an emergency braking signal is generated and sent to the electromagnetic brake controller to forcibly terminate the firing action.

6. The method for adjusting the firing depth of a power tool according to claim 1, characterized in that: The specific steps for updating the control parameter set under the corresponding operating condition in the multidimensional parameter mapping table are as follows: The actual displacement relative to the reference plane after the impact is obtained by a displacement sensor and used as the actual impact depth feedback value. The actual firing depth feedback value is compared with the target firing depth parameter, and the absolute deviation between the two is calculated. Determine whether the absolute deviation value is greater than the preset tolerance threshold. If it is greater, extract the workpiece material type, ambient temperature data and battery voltage status used in this firing process as working condition identification information. Based on the operating condition identification information, locate the corresponding subset of control parameters in the multidimensional parameter mapping table; The gradient descent algorithm is used to iteratively correct the target speed of the drive motor, the pre-compression threshold and the trigger timing in the subset of control parameters until the actual firing depth feedback value of the next firing action falls within the tolerance range. The corrected parameters are then written into a multi-dimensional parameter mapping table.

7. The method for adjusting the firing depth of a power tool according to claim 6, characterized in that: The specific construction process of the multidimensional parameter mapping table is as follows: When the electric striking tool is used for the first time, the calibration mode is executed. In this mode, multiple standard firing depth values ​​are set sequentially, and for each standard firing depth value, multiple firing experiments are conducted under a variety of preset typical working condition combinations. The typical working condition combinations include test workpieces with different hardness levels, different battery state of charge ranges, and different ambient temperature ranges. During each firing experiment, the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, the triggering sequence of the electromagnetic brake, and the actual firing depth feedback value were recorded simultaneously. Cluster analysis was performed on the control parameters required to achieve the target firing depth under each combination of working conditions to select the set of control parameters that make the absolute value of the deviation between the actual firing depth feedback value and the target firing depth less than the preset tolerance threshold. The selected set of control parameters is structured and stored according to the corresponding firing depth, workpiece hardness grade, battery state of charge and ambient temperature to form an initial multidimensional parameter mapping table. During subsequent use, the control parameter set for the corresponding operating condition in the multidimensional parameter mapping table is updated synchronously.

8. The adjustment system of the power tool firing depth adjustment method according to claim 1, characterized in that: include: The parameter acquisition and retrieval module acquires the target firing depth parameter and retrieves the corresponding initial control parameter set from the preset multi-dimensional parameter mapping table, including the target speed of the drive motor, the pre-compression threshold of the energy storage mechanism, and the triggering sequence of the electromagnetic brake. The multi-source state sensing module collects the current signal of the drive motor, the displacement signal of the energy storage mechanism, and the acceleration signal of the striking head in real time, calculates the current output torque, and determines the actual compression of the energy storage mechanism and the contact time between the striking head and the workpiece. The dynamic parameter correction module dynamically corrects the initial control parameter set based on the current output torque, contact time, and actual compression, and generates the corrected control command. The actuator correction module sends the corrected control command to the drive motor controller and the electromagnetic brake controller to adjust the power supply cycle of the drive motor and the activation timing of the electromagnetic brake. The feedback learning and optimization module records the actual firing depth feedback value after a single firing action is completed, compares it with the target firing depth parameter to calculate the absolute value of the deviation, and updates the control parameter set for the corresponding working condition in the multidimensional parameter mapping table if the absolute value of the deviation is greater than the preset tolerance threshold.

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