A method for implementing a pressure-sensitive key on a power tool by means of a pressure-sensitive device

Abstract

This application relates to a control method for pressure-sensitive buttons on power tools using a pressure-sensitive device. It is applied to power tools equipped with a pressure sensor, which is fixedly mounted on the first side of a PCB board. The PCB board has a force conduction opening in the pressing area corresponding to the pressure sensor. The method includes: receiving a pressure signal collected by the pressure sensor; determining whether the pressure signal is greater than a dynamic reference value; if so, the pressure signal is valid; calculating the difference between the pressure signal and the dynamic reference value; and determining the button state based on a comparison of the difference with a press threshold, a release threshold, and a preset confirmation time; generating and outputting power tool control commands based on the button state. The dynamic reference value is iteratively updated according to a preset update cycle based on the pressure signal. This method achieves stable recognition of pressing actions, reduces the probability of false triggering, and improves control reliability.

Description

Technical Field

[0001] This application relates to a method for implementing pressure-sensitive buttons, and more particularly to a method for implementing pressure-sensitive buttons on power tools using a pressure-sensitive device. Background Technology

[0002] Power tools typically have operation buttons on the surface of the housing for control functions such as start / stop, mode switching, and gear selection. Traditional solutions often use mechanical switches or push-button microswitches. The button travel is transmitted to the internal switch contacts through a button cap or lever at an opening in the housing to achieve on / off control. Under long-term high-frequency operation, vibration, impact, and dust splashing, this type of structure is prone to contact wear, rebound attenuation, jamming, and malfunction. The opening in the housing can also become a potential channel for dust and water ingress. Power tools operate under conditions such as motor start / stop, stall, and heavy load, often accompanied by power fluctuations, surge interference, and strong electromagnetic noise. Especially under light triggering requirements, without stable reference calibration and an effective press or release determination mechanism, incorrect button status judgments can easily occur under vibration, impact, or power supply disturbances, affecting the reliability and safety of power tool control. Summary of the Invention

[0003] The purpose of this application is to solve the problems mentioned above, such as the reliability of the button structure of power tools being easily affected by mechanical wear, environmental dust and vibration, and the pressure detection signal being prone to misjudgment, reference drift and trigger instability in complex electromagnetic and power interference environments.

[0004] According to one aspect of this application, a method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device is provided, comprising: S10, Receive the pressure signal collected by the pressure sensor; The pressure sensor is fixedly installed on the first side of the PCB board, and the PCB board has a force conduction opening in the pressing area corresponding to the pressure sensor; S20. Determine whether the pressure signal is greater than the dynamic reference value; S30. If so, determine that the pressure signal is valid, and calculate the difference between the pressure signal and the dynamic reference value; S40. Determine the button state based on the comparison result between the difference and the pressed threshold and released threshold; When the difference exceeds the press threshold and continues for a preset confirmation time, it is determined that the button has been pressed. When the difference is lower than the release threshold and continues to reach the preset confirmation time, it is determined to be released; S50. Generate and output power tool control commands based on the button states; The dynamic reference value is updated iteratively based on the pressure signal according to a preset update cycle to suppress reference drift caused by transient interference.

[0005] Preferably, if the pressure signal in step S20 is greater than the dynamic reference value, and the pressure signal is determined to be valid, then the dynamic reference value is iteratively updated based on the pressure signal according to a preset update cycle, including: S60. Calculate the difference between the pressure signal and the reference value, and determine whether the difference exceeds a preset threshold. S61. If the value exceeds the limit, the reference value is updated to the value of the current pressure signal. S62. If it does not exceed the preset step size, the reference value is adjusted step by step. The reference value is updated according to a preset update cycle and is cumulatively updated based on multiple changes in the received pressure signal. Specifically, if the pressure signal value is greater than the reference value, the reference value is increased by the preset step size; if the pressure signal value is less than the reference value, the reference value is decreased by the preset step size.

[0006] Preferably, if in step S20 the pressure signal is determined to be less than the dynamic reference value, and the pressure signal is deemed invalid, then the dynamic reference value is iteratively updated based on the pressure signal according to a preset update cycle, further comprising: S70. Determine whether the pressure signal changes according to the preset number of times it conforms to the set regularity standard. S71. If the condition is met, the invalid signal is determined to be a deliberate trigger, and the baseline value is adjusted according to the preset update cycle. S72. If it does not meet the requirements, it is determined to be a false trigger signal.

[0007] Preferably, the regularity standard in S70 includes: Receive the preset number of pressure signals within a preset time window; The difference between the pressure signal of the preset number of times and the dynamic reference value is calculated to obtain the difference sequence of the preset number of times; Determine whether the difference between adjacent differences in the difference sequence falls within a preset range of variation; Determine whether the sampling time intervals of the pressure signals for the preset number of times all fall within the preset interval range; Determine whether the dispersion of the difference sequence is less than a preset dispersion threshold; When the preset variation range, the preset interval range, and the preset dispersion threshold are all satisfied simultaneously, the pressure signal of the preset number of times is determined to conform to the regularity standard. Accordingly, adjusting the baseline value according to a preset update cycle in S71 includes: Within the preset time window, statistical calculations are performed on the pressure signals of the preset number of times to obtain representative values ​​of the pressure signals of the preset number of times. The baseline value is updated to the representative value, which includes: average, weighted average, or median.

[0008] Preferably, step S10 further includes amplifying the pressure signal, specifically by: amplifying the pressure signal through an operational amplifier inside the microcontroller, amplifying the pressure signal through an external operational amplifier, or amplifying the pressure signal through a high-precision analog-to-digital converter.

[0009] Preferably, after S10, the method further includes: Collect the maximum and minimum voltage values ​​of the motor of the power tool within a preset time period, and determine whether the difference between the maximum and minimum values ​​exceeds a preset difference threshold. If so, it is determined that there is an interference signal, and the press detection algorithm is turned off within the set time range, or the press threshold is increased; The press judgment algorithm analyzes the pressure signal collected by the pressure sensor and compares the pressure signal with the dynamic reference value and pressure threshold to confirm the trigger operation.

[0010] Preferably, after S10, the method further includes: Collect the current signal of the motor of the power tool and determine whether the operating current is greater than the set no-load current threshold. If the value is greater than the threshold, the power tool is determined to be in use. The press detection algorithm is then turned off within the set time range, or the press threshold is increased. The press judgment algorithm analyzes the pressure signal collected by the pressure sensor and compares the pressure signal with the dynamic reference value and pressure threshold to confirm the trigger operation.

[0011] Preferably, after S10, the method further includes: The current speed of the motor of the power tool is detected, and it is determined whether the current speed of the motor exceeds a preset speed range. If so, it is determined that there is a high load or stall situation, and the press detection algorithm is turned off within the set time range, or the press threshold is increased; The press judgment algorithm analyzes the pressure signal collected by the pressure sensor, compares the pressure signal with the dynamic reference value and the pressure threshold, and confirms the trigger operation.

[0012] Preferably, the pressure sensor in S10 is fixedly installed in either a downward pressing type or a rocker type. The downward type involves fixing the pressure sensor to the housing of the power tool, with the bottom of the pressure sensor being a cavity; The rocker type includes forming a C-shaped cutout in the housing or PCB board of the power tool. The C-shaped cutout forms a non-closed opening outline, so that a rocker is formed inside the C-shaped cutout by the housing material or PCB board. The rocker is integrally connected to the housing through a connecting part located at the cutout of the C-shaped cutout. The rocker arm has a touch area, and the pressure sensor is located on one side inside the PCB board; When pressure is applied to the touch area, the rocker body flexes relative to the connecting portion and transmits the pressure to the pressure sensor.

[0013] Preferably, the touch area is fitted with conductive silicone.

[0014] This application offers the following advantages: By comparing the pressure signal with a dynamic reference value and calculating the difference, the difference is jointly determined with the pressed threshold, released threshold, and preset confirmation time. This ensures that button status recognition is not dependent on instantaneous peak values ​​but is based on continuous and effective force changes, suppressing false triggering caused by transient fluctuations due to motor vibration, impact loads, and electromagnetic interference. The dynamic reference value is iteratively updated according to a preset update cycle based on the pressure signal. This automatically compensates for chronic offsets caused by sensor zero-point drift, structural stress changes, and environmental temperature changes during long-term use, avoiding sensitivity reduction or misjudgment due to reference drift in traditional fixed reference methods. This method achieves highly stable recognition of pressure-sensitive button signals without relying on complex mechanical stroke structures, improving the control reliability and safety of power tools under complex working conditions, while also contributing to the sealing and durability of the overall machine structure. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a flowchart illustrating a method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device, as described in this application. Figure 2A schematic diagram of the PCB board, pressure sensor, and force transmission opening; Figure 3 This is a schematic diagram of a C-shaped cutout.

[0017] The following are the reference numerals: 10, PCB board; 20, pressure sensor; 30, force transmission opening; 40, C-shaped cutout; 50, rocker arm; 60, connecting part. Detailed Implementation

[0018] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0019] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] Please refer to Figure 1 - Figure 3 This application provides a method for implementing pressure-sensitive buttons on power tools using pressure-sensitive devices, characterized by comprising: S10. Receive the pressure signal collected by the pressure sensor 20. The pressure sensor 20 is fixedly mounted on the first side of the PCB board 10. The PCB board 10 has a force conduction opening 30 in the pressing area corresponding to the pressure sensor 20. In this step, it should be noted that the pressure sensor 20 converts the external force acting on the pressing area of ​​the power tool housing into an electrical signal output. The pressure signal can be a change in voltage, resistance, or capacitance corresponding to the pressure magnitude, and is collected by the circuit to form a data signal that can be processed subsequently. The force conduction opening 30 in the pressing area of ​​the PCB board 10 corresponding to the pressure sensor 20 allows the deformation or pressure generated in the pressing area of ​​the housing to be transmitted along a predetermined path to the force-bearing surface of the pressure sensor 20, avoiding pressure dispersion by the local rigid structure of the PCB board 10, and improving pressure transmission efficiency and signal response consistency. Through this structural arrangement, effective sensing of pressure changes in the pressing area can be achieved within a limited space, providing a stable input for subsequent threshold determination.

[0022] S20. Determine whether the pressure signal is greater than the dynamic reference value. In this step, it should be noted that the dynamic reference value represents the reference level of the pressure signal in the current non-pressed state. It reflects the basic output of the sensor under the influence of factors such as assembly pre-tightening, static stress on the housing, and temperature changes. By comparing the real-time collected pressure signal with the dynamic reference value, a preliminary screening is performed to determine if there are significant press changes. When the pressure signal does not exceed the dynamic reference value, it indicates that the current pressure change has not met the recognition conditions for effective pressing; when the pressure signal is greater than the dynamic reference value, it indicates that the pressing area has undergone a positive change relative to the reference, making further confirmation of the button status necessary.

[0023] S30. If so, determine that the pressure signal is valid, and calculate the difference between the pressure signal and the dynamic reference value. In this step, it should be noted that the pressure signal is valid. By calculating the difference between the pressure signal and the dynamic reference value, the judgment object is converted from an absolute value to a relative change, making button recognition focus more on the incremental change caused by pressing.

[0024] S40. Based on the comparison result between the difference and the press threshold and release threshold, the button state is determined. When the difference exceeds the press threshold and continues for a preset confirmation time, it is determined as a press; when the difference is lower than the release threshold and continues for a preset confirmation time, it is determined as a release. In this step, it should be noted that when the difference exceeds the press threshold, it indicates that the pressing force has reached the required intensity; when the difference is lower than the release threshold, it indicates that the press has been released and returned to the release range. By distinguishing between the press threshold and the release threshold, a hysteresis-like determination effect can be formed, giving a clear boundary between pressing and releasing.

[0025] S50. Generate and output power tool control commands based on the button states. In this step, it should be noted that when a button state is determined to be pressed or released, the control logic generates control commands corresponding to the power tool's function based on the button state and outputs these control commands to the execution unit to control the power tool's operating state. The control commands may include start / stop control, working mode switching, gear changes, or other preset function trigger commands, with the specific command type matching the power tool's functional configuration.

[0026] The dynamic reference value is updated iteratively based on the pressure signal according to a preset update cycle to suppress reference drift caused by transient interference.

[0027] The technical solution implemented in this embodiment enables stable and accurate recognition of pressure-sensitive button operations even in working environments with strong vibrations, frequent impacts, and complex electromagnetic interference from power tools. By setting force transmission openings 30 in the corresponding pressing areas of the PCB board 10 and fixing the pressure sensor 20 to one side of the PCB board 10, external pressing pressure is transmitted to the sensor along a controllable path. By comparing the real-time pressure signal with a dynamic reference value, and making a comprehensive judgment based on the difference between the two, combined with the press threshold, release threshold, and confirmation time, button recognition is established on a continuous and effective basis of force change, rather than instantaneous fluctuations. This effectively suppresses transient interference caused by motor start-stop, sudden load changes, and external vibrations, significantly reducing the probability of false triggering and false release. The dynamic reference value's iterative update mechanism can adapt to the chronic offset caused by sensor zero-point drift, structural stress changes, and environmental temperature fluctuations, avoiding the problem of decreased button sensitivity or inaccurate judgment thresholds after long-term use, thus improving the long-term stability and consistency of the system.

[0028] In one specific embodiment, if the pressure signal in step S20 is greater than the dynamic reference value, and the pressure signal is determined to be valid, then the dynamic reference value is iteratively updated based on the pressure signal according to a preset update cycle, including: S60. Calculate the difference between the pressure signal and the reference value, and determine whether the difference exceeds a preset threshold. In this step, it should be noted that the difference between the current pressure signal and the current reference value is first calculated, and this difference is compared with a preset threshold to distinguish between significant offsets, slow offsets, and small fluctuations. When the difference exceeds the preset threshold, it indicates that the pressure signal has changed significantly relative to the reference value, which may correspond to a significant shift in the external environment, structural stress state, or sensor output baseline, requiring a more direct update strategy. When the difference does not exceed the preset threshold, it indicates that the current offset is within a controllable range, and a gradual adjustment method is more suitable to maintain the smoothness and stability of the reference update and suppress short-term disturbances from being mistakenly incorporated into the reference.

[0029] S61. If the difference exceeds the threshold, the reference value is updated to the current pressure signal value. In this step, it should be noted that when the difference exceeds a preset threshold, the reference value is updated to the current pressure signal value, allowing the reference value to quickly follow the current signal level and avoiding systematic deviations in subsequent difference calculations due to long-term lag in the reference value. The direct update action is triggered under the premise that the pressure signal is greater than the dynamic reference value and the signal is valid, reducing reference point jumps caused by invalid fluctuations.

[0030] S62. If the difference does not exceed the preset threshold, the reference value is adjusted gradually according to a preset step size. In this step, it should be noted that when the difference does not exceed the preset threshold, it indicates that the current pressure signal only has a small offset or slow drift relative to the reference value. The preset step size can be understood as the minimum increment allowed for the reference value to change during each update.

[0031] The reference value is updated according to a preset update cycle and is cumulatively updated based on multiple changes in the received pressure signal. Specifically, if the pressure signal value is greater than the reference value, the reference value is increased by the preset step size; if the pressure signal value is less than the reference value, the reference value is decreased by the preset step size.

[0032] The technical solution implemented in this embodiment achieves adaptive and controllable updates to the reference value, provided that the pressure signal is valid and greater than the dynamic reference value. When the pressure signal deviates significantly from the reference point, a direct update mechanism triggered by the difference threshold quickly aligns the reference point with the current signal level, avoiding systematic misjudgments caused by reference point lag. When the pressure signal only exhibits small fluctuations or slow drift, a gradual cumulative update at preset steps smoothly approaches the true baseline, reducing the drift risk caused by transient interference being incorporated into the reference point and providing a more reliable reference baseline for subsequent press and release threshold determination.

[0033] In one specific embodiment, if in step S20 it is determined that the pressure signal is not greater than the dynamic reference value, then the pressure signal is determined to be invalid. The dynamic reference value is then iteratively updated based on the pressure signal according to a preset update cycle, further comprising: S70. Determine whether the pressure signal changes according to the preset number of times it conforms to the set regularity standard. In this step, it should be noted that pressure signals that have been determined in the previous judgment not to exceed the dynamic reference value are invalid signals at the amplitude level, but such signals may still contain regular fluctuations with a certain trend. When the pressure signal does not exceed the dynamic reference value, the data from a single pressure signal is insufficient to distinguish between actual operation and random disturbance. Therefore, this step introduces a preset number of continuous pressure signals as the basis for judgment. The changes are used to determine whether the trend, fluctuation direction, and amplitude of the pressure signal relative to the reference value within multiple sampling points or multiple update cycles exhibit repeatable and predictable characteristics. For example, it may show continuous, unidirectional gradual increases or decreases within the preset number of times, or exhibit relatively consistent periodic fluctuations within an allowable range. This allows the system to determine multiple changes in the pressure signal as accidental touches and ignore user touch or slow triggering scenarios even when the pressure signal amplitude has not reached the current reference value.

[0034] S71. If the conditions are met, the invalid signal is determined to be a deliberate trigger, and the reference value is adjusted according to a preset update cycle. In this step, it should be noted that when the pressure signal meets the regularity standard within a preset number of times, it indicates that the signal change is more likely caused by continuous force application or rhythmic triggering by the user. Although its amplitude does not exceed the dynamic reference value, it still possesses identifiable intent. In this case, the invalid signal is determined to be a deliberate trigger, and the reference value is adjusted within the preset update cycle so that the reference value can be updated to the signal level corresponding to the deliberate trigger.

[0035] S72. If it does not meet the requirements, it is determined to be a false trigger signal. In this step, it should be noted that when the pressure signal does not meet the regularity standard within the preset number of times, it indicates that its change lacks consistency or repeatability. It is usually more consistent with random fluctuations caused by power tool vibration, impact, structural rebound, or noise coupling, so it is determined to be a false trigger signal.

[0036] The technical solution implemented in this embodiment, when the pressure signal does not exceed the dynamic reference value, achieves the differentiation and identification of light touch or slow triggering intentions by introducing a preset number of trend analysis and regularity standard judgment mechanism. When the signal change shows regularity, it is identified as a conscious trigger, and the reference value is adjusted in a controlled manner within a preset update cycle, improving the recognizability and interaction consistency in light touch scenarios; when the signal change is irregular, it is identified as a false touch signal and isolated, reducing the probability of false triggering and maintaining the stability of the reference value.

[0037] In one specific embodiment, the regularity standard in S60 includes: The pressure signals are received a preset number of times within a preset time window. It should be noted that the preset time window is used to limit the time range of signal acquisition, ensuring that the determination of multiple pressure signals is based on a relatively continuous operation phase.

[0038] The pressure signals from the preset number of times are compared with the dynamic reference value to calculate the difference, resulting in a sequence of differences for the preset number of times. It should be noted that by comparing each collected pressure signal with the current dynamic reference value to obtain the corresponding difference, the analysis object can be uniformly converted into a relative change, reducing the deviation caused by the influence of temperature, assembly stress, and long-term drift on the absolute value.

[0039] The step involves determining whether the differences between adjacent values ​​in the difference sequence all fall within a preset range. It should be noted that the difference between adjacent values ​​represents the amplitude of pressure signal variation between adjacent sampling points. When the difference between adjacent values ​​is too large or changes drastically, it often corresponds to transient impacts or noise interference; when it stably falls within a reasonable range, it is more likely to correspond to continuous force or rhythmic manual operation.

[0040] The step involves determining whether the sampling time intervals of the pressure signals for the preset number of times all fall within a preset interval range. It should be noted that the sampling time interval reflects the uniformity of signal acquisition over time. If the sampling intervals are stable and fall within the preset interval range, it indicates that the changes corresponding to the difference sequence are formed under a regular time rhythm. If the sampling intervals are unstable or have significant jumps, it may mean that there is interference or system abnormality during the sampling process, making it difficult to determine as a regular operation.

[0041] Determine whether the dispersion of the difference sequence is less than a preset dispersion threshold. In this step, it should be noted that the dispersion of the difference sequence represents the degree of concentration of the overall fluctuations of the sequence, and can be reflected by variance, range, or other statistical indicators. A smaller dispersion indicates that the difference sequence is concentrated around a certain trend, the fluctuation amplitude is controlled, and it is more consistent with the signal characteristics generated by continuous force application; a larger dispersion indicates that the signal fluctuations are scattered and highly random, and it is more likely to originate from vibration or noise.

[0042] When the preset variation range, the preset interval range, and the preset dispersion threshold are all satisfied simultaneously, the pressure signal of the preset number of times is determined to conform to the regularity standard. In this step, it should be noted that by comprehensively constraining the continuity of the variation amplitude, the stability of the time interval, and the overall dispersion, only when the pressure signal exhibits a consistent trend in amplitude variation, time rhythm, and statistical stability is it considered a regular change with operational intent.

[0043] Accordingly, adjusting the baseline value according to a preset update cycle in S71 includes: Within the preset time window, statistical calculations are performed on the pressure signals of the preset number of times to obtain representative values ​​for the pressure signals of the preset number of times. It should be noted in this step that after determining that the pressure signals conform to a regularity standard, statistical calculations need to be performed on multiple pressure signals within this time window to extract statistical results that can represent the overall level.

[0044] The baseline value is updated to the representative value, which includes the average, weighted average, or median. It should be noted that the average is suitable for scenarios with relatively smooth changes, the weighted average can highlight the influence of recent signals, and the median has a stronger ability to suppress outliers.

[0045] The technical solution implemented in this embodiment comprehensively judges multiple pressure signals within a preset time window based on multi-dimensional characteristics such as amplitude variation trends, sampling time rhythm, and statistical dispersion. It accurately identifies regular light touches or slow force applications and smoothly updates the reference value based on statistically obtained representative values, enabling the reference to adaptively conform to actual operating conditions. This maintains good recognition sensitivity even with small pressure signal amplitudes and preserves the stability and long-term consistency of the reference value under complex operating conditions, improving the anti-interference capability and judgment reliability of pressure-sensitive buttons.

[0046] In one specific embodiment, S10 further includes amplifying the pressure signal, specifically including: amplifying the pressure signal through an operational amplifier inside the microcontroller, amplifying the pressure signal through an external operational amplifier, or amplifying the pressure signal through a high-precision analog-to-digital converter. In this embodiment, it should be noted that the amplification method can employ at least one of the following implementation paths: First, amplifying the pressure signal through an operational amplifier inside the microcontroller. This method utilizes the analog front-end resources integrated into the microcontroller, enabling the pressure signal to complete gain setting and amplification output within the chip. Second, amplifying the pressure signal through an external operational amplifier. This method involves setting an independent operational amplifier outside the microcontroller, adapting the gain, bandwidth, and input / output range. Third, amplifying the pressure signal through a high-precision analog-to-digital converter. This method focuses on improving the effective resolution at the signal conversion stage, enabling the pressure signal to have finer quantization steps after digitization.

[0047] The technical solution of this embodiment improves the effective amplitude range and sampling resolution of the pressure signal when the pressure signal amplitude is small or changes slightly. This enhances the sensitivity and consistency of subsequent dynamic reference value comparison, difference calculation, and press and release state determination, reduces the risk of misjudgment caused by quantization error, and improves the recognition stability of pressure-sensitive buttons and the control reliability of power tools under vibration, shock, and electromagnetic interference environments.

[0048] In one specific embodiment, the process further includes the following after S10: The maximum and minimum voltage values ​​of the motor of the power tool are collected within a preset time period, and it is determined whether the difference between the maximum and minimum values ​​exceeds a preset difference threshold. It should be noted that during start-up, shutdown, stall, and heavy load switching, the motor power supply voltage may experience significant fluctuations or transient drops and rebounds. Such voltage fluctuations can easily be superimposed on the signal link of pressure sensor 20 through the power supply circuit, ground circuit, or electromagnetic coupling, forming interference components unrelated to the pressing behavior. The motor voltage is collected within the preset time period, and the maximum and minimum voltage values ​​are extracted. The difference between the two values ​​is calculated to quantify the voltage fluctuation intensity within that time period. When the difference exceeds the preset difference threshold, it can be considered that there is a significant power supply disturbance or surge change on the motor side, thus presuming an increased probability of interference to the pressure signal during that time period. By introducing motor voltage fluctuations as a basis for interference discrimination, external operating condition disturbances can be bypassed and identified without relying on the pressure signal itself, providing a reliable trigger condition for switching subsequent pressing judgment strategies.

[0049] If so, interference is detected, and the press detection algorithm is either disabled within a set time range or the press threshold is increased. It's important to note that when a motor voltage fluctuation exceeds the threshold, the system marks that time period as a high-interference zone and implements suppression strategies to prevent false triggering. Disabling the press detection algorithm within the set time range means pausing the key status determination and trigger confirmation of the pressure signal during the high-interference zone, preventing the pressure signal from participating in key recognition during the interference period, and resuming judgment after the interference ends. Alternatively, increasing the press threshold means temporarily raising the threshold condition used to determine the press action during the high-interference zone, so that the press detection is only triggered when there is a larger difference or a stronger press input, thus resisting signal rise or spikes caused by interference by increasing the trigger threshold.

[0050] The press judgment algorithm analyzes the pressure signal collected by the pressure sensor 20 and compares the pressure signal with the dynamic reference value and pressure threshold to confirm the trigger operation.

[0051] The technical solution implemented in this embodiment uses the difference between the maximum and minimum values ​​of the motor voltage within a preset time as the basis for judging the intensity of interference under operating conditions. When power fluctuations, surge impacts, or sudden load changes increase the probability of interference, the press judgment strategy is switched in a timely manner. By pausing press judgment or temporarily increasing the press threshold within a set time range, the risk of false triggering caused by abnormal fluctuations in pressure signals during interference is significantly reduced, thereby improving the anti-interference capability, judgment stability, and safety and reliability of the pressure-sensitive button in complex operating conditions and the power tool control process.

[0052] In one specific embodiment, the process further includes the following after S10: The current signal of the motor of the power tool is collected to determine whether the operating current exceeds a set no-load current threshold. It should be noted that the motor operating current of the power tool varies significantly under different operating conditions, such as no-load, light-load, and heavy-load. The no-load current threshold represents the typical upper limit of the current when the motor is not in operation or under no significant load. When the collected operating current exceeds this threshold, it usually means that the power tool is performing cutting, grinding, drilling, or other operations, or at least is under significant load. Because the power tool is in use, vibration, impact, and electromagnetic noise are often more intense and may affect the output of the pressure sensor 20 through structural transmission or electrical coupling, increasing the risk of false pressure readings.

[0053] If the current exceeds the threshold, the power tool is determined to be in use. In this case, the press detection algorithm is either disabled within a set time range or the press threshold is increased. It's important to note that when the operating current exceeds the no-load current threshold, the power tool is considered to be in use, and the press triggering strategy is suppressed to address the high vibration and interference characteristics of this state. Disabling the press detection algorithm within the set time range means pausing the determination of the button status and trigger confirmation of the pressure signal within a specified time interval after detecting the use state, preventing misidentification due to fluctuations in the pressure signal resembling a press caused by continuous vibration or impact during operation. Alternatively, increasing the press threshold means temporarily raising the press detection threshold during the use state, allowing the system to trigger only when there is a more obvious and stronger press input, thus enhancing anti-interference capabilities by raising the trigger threshold. The choice between these two methods can be made based on the power tool's interaction requirements and safety strategy, prioritizing prevention of accidental touches during operation while maintaining high trigger sensitivity during non-operational periods.

[0054] The press judgment algorithm analyzes the pressure signal collected by the pressure sensor 20 and compares the pressure signal with the dynamic reference value and pressure threshold to confirm the trigger operation.

[0055] The technical solution of this embodiment achieves rapid identification of whether the power tool is in operation by collecting the motor current and comparing it with the no-load current threshold. When in operation, it suppresses pressure signal fluctuations caused by vibration, impact and electromagnetic noise from entering the trigger path by pausing the pressing judgment or temporarily increasing the pressing threshold. This significantly reduces the probability of false triggering during operation, thereby improving the anti-interference ability and judgment stability of the pressure-sensitive button under complex working conditions, and enhancing the reliability and safety of power tool control.

[0056] In one specific embodiment, the process further includes the following after S10: The current speed of the power tool's motor is detected, and its speed is assessed to determine if it exceeds a preset speed range. It's important to note that motor speed directly reflects the power tool's operating condition. When the power tool is unloaded or in normal cutting mode, the motor speed typically fluctuates within a relatively stable range. However, under high load, jamming, or stalling conditions, the motor speed often deviates significantly, such as experiencing a rapid drop, violent fluctuations, or falling into an abnormally low speed range. The preset speed range defines the permissible speed range for the motor under normal operating conditions. By real-time detection of the motor's current speed and determination of whether it exceeds this range, abnormal operating conditions that may cause strong vibrations, strong electromagnetic interference, or power supply disturbances can be identified without relying on the pressure signal itself, providing trigger conditions for subsequent pressure judgment strategies.

[0057] If so, a high load or stall condition is identified, and the press detection algorithm is either disabled within a set time range or the press threshold is increased. It's important to note that when the motor's current speed exceeds the preset range, it indicates a possible high load or stall-related abnormal state. In this case, the power tool experiences increased vibration and more frequent impacts, and the drive system may generate more significant electromagnetic noise and power fluctuations, potentially causing unintended fluctuations in the pressure sensor 20 output. To prevent false triggering under these abnormal conditions, this step employs a trigger suppression control strategy after identifying a high load or stall condition. The press detection algorithm is disabled within a set time range, preventing the pressure signal from participating in button trigger confirmation during that period, thus directly blocking the false trigger path. Alternatively, the press threshold is increased, requiring a larger effective pressure change to trigger the press action, reducing the probability of random fluctuations exceeding the threshold under abnormal conditions.

[0058] The press judgment algorithm analyzes the pressure signal collected by the pressure sensor 20, compares the pressure signal with the dynamic reference value and the pressure threshold, and confirms the trigger operation.

[0059] The technical solution of this embodiment quickly identifies abnormal working conditions such as high load or stall by detecting the current speed of the motor in real time and comparing it with a preset speed range. During the abnormal working conditions, it suppresses abnormal fluctuations in pressure signals caused by strong vibration, impact and electromagnetic noise from entering the triggering process by pausing the pressing judgment or temporarily increasing the pressing threshold. This significantly reduces the probability of false triggering, thereby improving the anti-interference ability and judgment stability of the pressure-sensitive button under complex working conditions, and enhancing the reliability and safety of power tool control.

[0060] In one specific embodiment, the pressure sensor 20 in S10 is fixedly installed in either a downward pressing type or a rocker type. The downward type involves fixing the pressure sensor 20 to the housing of the power tool, with the bottom of the pressure sensor 20 being a cavity; The rocker type includes a C-shaped cutout 40 formed on the housing or PCB board 10 of the power tool. The C-shaped cutout 40 forms a non-closed opening outline, so that a rocker 50 is formed inside the C-shaped cutout 40 by the housing material or PCB board 10. The rocker 50 is integrally connected to the housing through a connecting part 60 located at the cutout of the C-shaped cutout 40. The rocker arm 50 has a touch area, and the pressure sensor 20 is located on one side inside the PCB board 10; When pressure is applied to the touch area, the rocker body 50 flexes relative to the connecting portion 60 and transmits the pressure to the pressure sensor 20.

[0061] In this embodiment, it should be noted that the pressure sensor 20 is directly fixed to the outer shell, allowing the force generated in the pressing area to act on the sensor's force-bearing surface along a shorter path. The hollow structure at the bottom provides space for the sensor to deform under stress, enabling the sensor to produce measurable deformation or stress changes when pressed, without being restricted by the rigid support structure below, thus maintaining high sensitivity and linear response. The connecting part 60 acts as a flexible fulcrum, and the rocker 50 undergoes predictable flexural deformation around this part when subjected to force, rather than overall rigid displacement. The rocker 50 has a touch area to limit the user's force application position, concentrating the external force on the designed effective deformation area. The pressure sensor 20 is located on one side inside the PCB board 10, keeping the sensor away from the external direct contact environment, reducing the impact of dust, impact, and liquid intrusion on the sensor's stability, and facilitating integration with the circuit system. When pressure is applied to the touch area, the rocker 50 body flexes relative to the connecting part 60 and transmits the pressure to the pressure sensor 20. This transmission process can be achieved by displacement, pressing or contact change of the lower surface of the rocker 50, so that the pressure sensor 20 obtains continuous and repeatable signal changes corresponding to the pressing action.

[0062] The technical solution implemented in this embodiment establishes a stable and predictable mechanical force transmission path through either a pressure-type or a rocker-type structure, thereby improving the repeatability and anti-interference capability of the pressure signal from the source. The pressure-type structure provides effective deformation space for the pressure sensor 20 through a bottom cavity, allowing for noticeable signal changes even with slight pressure, while reducing sensitivity attenuation caused by assembly deviations and rigid supports. The rocker-type structure utilizes a C-shaped cutout to form an integrated elastic rocker 50, providing controllable flexibility while ensuring structural strength. This allows for stable pressure transmission to the pressure sensor 20 inside the PCB after force is applied to the touch area, effectively isolating external environmental influences. Both methods improve the consistency, long-term stability, and environmental adaptability of pressure detection, providing a solid structural foundation for reliable identification of pressure-sensitive buttons under vibration, shock, and complex working conditions, enhancing the reliability and safety of power tool control.

[0063] In one specific embodiment, conductive silicone is adhered to the touch area. In this embodiment, it should be noted that a functional layer with elastic cushioning and conductive properties is formed between the user's finger and the touch area. The conductive silicone can be tightly adhered to the surface of the touch area or embedded in a local groove within the touch area, undergoing elastic deformation under external force and distributing the pressure more evenly to the underlying structure. The conductive silicone possesses certain conductivity, and in the complex electromagnetic environment of power tools, it can serve as a static discharge channel or shielding coupling path for the touch area, reducing the possibility of static electricity from the human body or external electromagnetic interference directly coupling to the pressure sensor 20 and its signal lines.

[0064] The technical solution implemented in this embodiment introduces a functional layer with elastic and conductive properties between the touch area and the internal force transmission structure. This makes the pressure transmission more uniform and smooth, reducing structural fatigue and signal fluctuations caused by local stress concentration, and improving the stability and repeatability of the pressure sensor 20 output. The conductive properties form a buffer and discharge path for electrostatic and electromagnetic interference, reducing the impact of complex electrical environments on pressure signal acquisition and enhancing the system's anti-interference capability. Furthermore, the elastic recovery properties of the conductive silicone help maintain consistent pressing feel over long-term use and, to some extent, improve the sealing and durability of the touch area, thereby comprehensively improving the reliability of the pressure-sensitive button structure, its environmental adaptability, and the stability and safety during the use of power tools.

[0065] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device, characterized in that, include: S10, Receive the pressure signal collected by the pressure sensor; The pressure sensor is fixedly installed on the first side of the PCB board, and the PCB board has a force conduction opening in the pressing area corresponding to the pressure sensor; S20. Determine whether the pressure signal is greater than the dynamic reference value; S30. If so, determine that the pressure signal is valid, and calculate the difference between the pressure signal and the dynamic reference value; S40. Determine the button state based on the comparison result between the difference and the pressed threshold and released threshold; When the difference exceeds the press threshold and continues for a preset confirmation time, it is determined that the button has been pressed. When the difference is lower than the release threshold and continues to reach the preset confirmation time, it is determined to be released; S50. Generate and output power tool control commands based on the button states; The dynamic reference value is updated iteratively based on the pressure signal according to a preset update cycle to suppress reference drift caused by transient interference.

2. The method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 1, characterized in that, If the pressure signal in step S20 is greater than the dynamic reference value, and the pressure signal is deemed valid, then the dynamic reference value is iteratively updated based on the pressure signal according to a preset update cycle, including: S60. Calculate the difference between the pressure signal and the reference value, and determine whether the difference exceeds a preset threshold. S61. If the value exceeds the limit, the reference value is updated to the value of the current pressure signal. S62. If it does not exceed the preset step size, the reference value is adjusted step by step. The reference value is updated according to a preset update cycle and is cumulatively updated based on multiple changes in the received pressure signal. Specifically, if the pressure signal value is greater than the reference value, the reference value is increased by the preset step size; if the pressure signal value is less than the reference value, the reference value is decreased by the preset step size.

3. The method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 2, characterized in that, If, in step S20, it is determined that the pressure signal is not greater than the dynamic reference value, then the pressure signal is deemed invalid. The dynamic reference value is then iteratively updated based on the pressure signal according to a preset update cycle, further including: S70. Determine whether the pressure signal changes according to the preset number of times it conforms to the set regularity standard. S71. If the condition is met, the invalid signal is determined to be a deliberate trigger, and the baseline value is adjusted according to the preset update cycle. S72. If it does not meet the requirements, it is determined to be a false trigger signal.

4. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 3, characterized in that, The regularity criteria in S70 include: Receive the preset number of pressure signals within a preset time window; The difference between the pressure signal of the preset number of times and the dynamic reference value is calculated to obtain the difference sequence of the preset number of times; Determine whether the difference between adjacent differences in the difference sequence falls within a preset range of variation; Determine whether the sampling time intervals of the pressure signals for the preset number of times all fall within the preset interval range; Determine whether the dispersion of the difference sequence is less than a preset dispersion threshold; When the preset variation range, the preset interval range, and the preset dispersion threshold are all satisfied simultaneously, the pressure signal of the preset number of times is determined to conform to the regularity standard. Accordingly, adjusting the baseline value according to a preset update cycle in S71 includes: Within the preset time window, statistical calculations are performed on the pressure signals of the preset number of times to obtain representative values ​​of the pressure signals of the preset number of times. The baseline value is updated to the representative value, which includes: average, weighted average, or median.

5. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 1, characterized in that, S10 further includes amplifying the pressure signal, specifically by: amplifying the pressure signal through an operational amplifier inside the microcontroller, amplifying the pressure signal through an external operational amplifier, or amplifying the pressure signal through a high-precision analog-to-digital converter.

6. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 1, characterized in that, Following S10, the following is also included: Collect the maximum and minimum voltage values ​​of the motor of the power tool within a preset time period, and determine whether the difference between the maximum and minimum values ​​exceeds a preset difference threshold. If so, it is determined that there is an interference signal, and the press detection algorithm is turned off within the set time range, or the press threshold is increased; The press judgment algorithm analyzes the pressure signal collected by the pressure sensor and compares the pressure signal with the dynamic reference value and pressure threshold to confirm the trigger operation.

7. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 1, characterized in that, Following S10, the following is also included: Collect the current signal of the motor of the power tool and determine whether the operating current is greater than the set no-load current threshold. If the value is greater than the threshold, the power tool is determined to be in use. The press detection algorithm is then turned off within the set time range, or the press threshold is increased. The press judgment algorithm analyzes the pressure signal collected by the pressure sensor and compares the pressure signal with the dynamic reference value and pressure threshold to confirm the trigger operation.

8. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 1, characterized in that, Following S10, the following is also included: The current speed of the motor of the power tool is detected, and it is determined whether the current speed of the motor exceeds a preset speed range. If so, it is determined that there is a high load or stall situation, and the press detection algorithm is turned off within the set time range, or the press threshold is increased; The press judgment algorithm analyzes the pressure signal collected by the pressure sensor, compares the pressure signal with the dynamic reference value and the pressure threshold, and confirms the trigger operation.

9. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 1, characterized in that, The pressure sensor in S10 can be fixed in either a downward pressing type or a rocker type. The downward type involves fixing the pressure sensor to the housing of the power tool, with the bottom of the pressure sensor being a cavity; The rocker type includes forming a C-shaped cutout in the housing or PCB board of the power tool. The C-shaped cutout forms a non-closed opening outline, so that a rocker is formed inside the C-shaped cutout by the housing material or PCB board. The rocker is integrally connected to the housing through a connecting part located at the cutout of the C-shaped cutout. The rocker arm has a touch area, and the pressure sensor is located on one side inside the PCB board; When pressure is applied to the touch area, the rocker body flexes relative to the connecting portion and transmits the pressure to the pressure sensor.

10. A method for implementing pressure-sensitive buttons on a power tool using a pressure-sensitive device according to claim 9, characterized in that, The touch area is fitted with conductive silicone.

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