Power tool

Abstract

A control method for a power tool, and the power tool, which are applied to the field of power tools. The control method comprises: acquiring a current change rate of the power tool during operation, and determining whether a fastener has begun to seat; and upon seating of the fastener, acquiring current parameters within a preset time period, and generating a control instruction on the basis of the current parameters, such that the tool automatically enters a first operating mode or a second operating mode. The type of a workpiece is automatically identified, and a corresponding operating mode is executed, thereby avoiding the inconvenience of frequent switching between tool modes and improving the use efficiency of the tool.

Description

power tools Technical Field

[0001] This application relates to the field of power tools, and in particular to a power tool and a control method thereof. Background Technology

[0002] When using torque output tools such as electric drills and screwdrivers, users face many inconveniences. For example, when operating power tools, the user must manually detect when the bottom of the screw has touched the surface of the workpiece (hereinafter referred to as "seat") before turning on the switch to stop the torque output of the power tool. Since the screw seat time is very short, users often do not have enough time to react and control the operation of the tool in time, so it is easy to drive the screw too deep into the workpiece, or even damage the workpiece.

[0003] In existing technologies, some designs automatically control the tool to stop rotating when the screw bottoms out, depending on different working conditions. For example, Chinese invention patent application CN111775117B sets up metal mode and woodworking mode, so that the tool's automatic stop control can adapt to various working conditions. However, this method requires users to frequently switch operating modes when facing complex working conditions, which actually reduces work efficiency.

[0004] Therefore, it is necessary to design an electric tool and its control method that can automatically identify the type of workpiece and automatically perform different operations according to the type of workpiece in order to solve the above-mentioned technical problems. Summary of the Invention

[0005] In view of the above, this application provides a control method for an electric tool and an electric tool in order to solve the technical problems existing in the background art.

[0006] The control method for the power tool includes:

[0007] Obtain the rate of change of current during tool operation;

[0008] The current change rate is used to determine whether the fastener being acted upon by the power tool has begun to sit; when it is determined that the fastener has begun to sit, the current parameters within a preset time period are obtained.

[0009] A control command is generated based on the current parameters, and the control command is used to put the power tool into a first operating mode or a second operating mode.

[0010] In one alternative embodiment, determining whether the fastener operated by the power tool has begun to settle based on the rate of change of current includes:

[0011] If the current change rate is greater than or equal to the current change rate threshold, then it is determined that the fastener operated by the power tool has begun to sit.

[0012] In one optional implementation, the preset time period is a period of time starting from the moment the fastener begins to be seated; the current parameter is the average current value within the preset time period.

[0013] In an optional implementation, generating control commands based on the current parameters includes:

[0014] If the average current is less than the average current threshold, a first control command is output to cause the power tool to enter a first operating mode, which is a wooden board operating mode.

[0015] In an optional implementation, generating control commands based on the current parameters includes:

[0016] If the average current is greater than or equal to the average current threshold, a second control command is output to cause the power tool to enter a second operating mode, which is a metal operating mode.

[0017] The average current threshold is between the average current of the power tool when it is applied to the wooden board during the preset time period and the average current of the power tool when it is applied to the metal plate during the preset time period.

[0018] In an alternative implementation, the step of when the fastener begins to sit includes:

[0019] The power tool slows down and acquires the peak current generated by the slowdown within a preset time period; the preset time period is a period of time starting from the beginning of the fastener being seated and ending at a point in time after the power tool slows down.

[0020] In an optional implementation, generating control commands based on the current parameters includes:

[0021] If the peak current is less than the peak current threshold, a first control command is output to cause the power tool to enter a first operating mode, which is a wooden board operating mode.

[0022] In an optional implementation, generating control commands based on the current parameters includes:

[0023] If the peak current is greater than or equal to the peak current threshold, a second control command is output to cause the power tool to enter a second operating mode, which is a metal operating mode.

[0024] The peak current threshold is between the peak current of the power tool when the fastener is placed on the wooden board and the peak current of the power tool when the fastener is placed on the metal plate.

[0025] In one optional implementation, when the power tool enters the first operating mode, a third control command is executed to reduce the speed of the power tool; when the power tool enters the second operating mode, a fourth control command is executed to stop the power tool.

[0026] In one alternative embodiment, the power tool includes:

[0027] The output shaft is used to output torque.

[0028] Housing for accommodating the motor;

[0029] An electric motor is used to drive the output shaft to rotate;

[0030] A transmission assembly, which connects the motor and the output shaft;

[0031] A current detection unit is used at least to detect the current during operation of the power tool;

[0032] The power tool is characterized in that it further includes:

[0033] Controller; the controller includes a processing unit and a storage unit;

[0034] The aforementioned storage unit is used to store control instructions;

[0035] The processing unit is configured to execute the control instructions to implement the power tool control method as described in any one of claims 1 to 9.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0037] (1) This invention determines whether a fastener is seated by monitoring the rate of change of load current during tool operation. Then, it compares the current parameters after the fastener begins to be seated with the current threshold to determine the workpiece type. This enables the tool to automatically identify the workpiece type and execute the corresponding operation mode. This avoids the problem of frequently switching tool modes when facing complex working conditions and can effectively improve the efficiency of tool use.

[0038] (2) This invention determines the workpiece type and adopts the corresponding operation mode based on the current parameters after the workpiece is initially seated, rather than using the current parameters during the screwing-in process. During screwing-in, the uneven material of the workpiece causes significant fluctuations in the current, which can easily affect the result of workpiece type determination. In contrast, the current parameter value when the workpiece first contacts the fastener can more accurately reflect the workpiece's hardness. Therefore, using the current parameter value at the initial seating stage for workpiece type determination can effectively improve the accuracy of workpiece type identification.

[0039] (3) The present invention further identifies the workpiece type by immediately controlling the power tool to perform a speed reduction operation after the fastener begins to be seated, and obtaining the peak current value generated by the reduction in tool power after the fastener begins to be seated; comparing the peak current value with a current threshold. Based on the workpiece type, the corresponding operation mode is executed on the basis of the speed reduction operation. Controlling the power tool to reduce speed before determining the workpiece type avoids the situation where the power tool breaks through the workpiece before it can perform the next step due to excessive speed. At the same time, the peak current generated by the speed reduction operation can be directly used to determine the workpiece type, reducing the impact of sudden current changes and making the identification result more accurate. Additional aspects and advantages of the embodiments of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the embodiments of this application. Attached Figure Description

[0040] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, are provided. The drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show details of those features. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0041] Figure 1 is a schematic diagram of the power tool in an embodiment of this application;

[0042] Figure 2 is a schematic block diagram of a specific example of a power tool in the embodiments of this application.

[0043] Figure 3 is a schematic diagram of the steps of a power tool control method in one embodiment of this application;

[0044] Figure 4 is a logical schematic diagram of a power tool control method in one embodiment of this application;

[0045] Figure 5 is a current change diagram of a specific example of the control method being executed on a wooden board in the embodiments of this application;

[0046] Figure 6 is a current variation diagram of a specific example of the control method being executed on a metal plate in the embodiments of this application;

[0047] Figure 7 is a schematic diagram of the steps of a power tool control method in another embodiment of this application;

[0048] Figure 8 is a logical schematic diagram of a power tool control method in another embodiment of this application;

[0049] Figure 9 is a current change diagram of another specific example of the control method being applied to a wooden board in the embodiments of this application;

[0050] Figure 10 is a current variation diagram of another specific example when the control method in the embodiments of this application is executed on a metal plate;

[0051] Figure 11 is a schematic block diagram of a specific example of the controller in an embodiment of this application. Detailed Implementation

[0052] To make the technical solution and beneficial effects of the present invention more apparent and understandable, a detailed description is provided below by listing specific embodiments. The accompanying drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which this application pertains.

[0053] The embodiments described in this application are not exhaustive, but merely illustrative of some embodiments, and are not intended to limit the scope of protection of this application. Unless otherwise specified, each step in a particular embodiment can be implemented as an independent embodiment, and the steps can be arbitrarily combined. For example, a solution after removing some steps in a particular embodiment can also be implemented as an independent embodiment, and the order of the steps in a particular embodiment can be arbitrarily interchanged. Furthermore, the optional implementation methods in a particular embodiment can be arbitrarily combined; moreover, the embodiments can be arbitrarily combined with each other. For example, some or all steps of different embodiments can be arbitrarily combined, and a particular embodiment can be arbitrarily combined with the optional implementation methods of other embodiments.

[0054] In each embodiment of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of the embodiments are consistent and can be referenced by each other. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0055] The terminology used in the embodiments of this application is for the purpose of describing specific embodiments only and is not intended to limit the scope of this application.

[0056] In the embodiments of this application, unless otherwise stated, elements expressed in the singular form, such as "a," "an," "the," "the," "the," "the," "the," "the," "this," etc., can mean "one and only one," or "one or more," "at least one," etc. For example, when using articles such as "a," "an," "the," etc. in translation, the noun after the article can be understood as either a singular expression or a plural expression.

[0057] In the embodiments of this application, "multiple" refers to two or more. In some embodiments, the terms "at least one of", "one or more", "a plurality of", "multiple" and the like can be used interchangeably.

[0058] The prefixes "first," "second," etc., used in the embodiments of this application are merely for distinguishing different descriptive objects and do not impose restrictions on the position, order, priority, value, or content of the descriptive objects. The description of the descriptive objects is based on the claims or the context of the embodiments, and the use of prefixes should not constitute unnecessary restrictions. For example, the numerical value of the descriptive object is not limited by ordinal numbers and can be one or more. Taking "first device" as an example, the numerical value of "device" can be one or more. Furthermore, the objects modified by different prefixes can be the same or different. For example, if the descriptive object is "device," then "first device" and "second device" can be the same device or different devices, and their types can be the same or different.

[0059] In some embodiments, the term "connection" can refer to the transmission of electrical signals or data between the connected end and the connected end, and can be understood as "electrical connection," "communication connection," etc. A "connection" can be a direct connection between two components, an indirect connection established through other components, a connection within two components, or any other possible form of connection.

[0060] In modern construction and industrial fields, electric impact screwdrivers are widely used as efficient fastening tools in various working environments. To adapt to different operational needs, existing impact screwdrivers are designed with multiple control modes, such as metal operation mode and wood operation mode, to improve work efficiency and ensure work quality.

[0061] The metal operation mode is a control mode specifically designed for rigid materials such as corrugated steel sheets and steel plates. In this mode, the screwdriver can automatically stop operating after the fastener reaches the predetermined position, thereby preventing damage to the material or affecting the stability of the structure due to overtightening.

[0062] The wood panel operation mode is designed to accommodate more fragile materials such as wood panels and drywall. During the tightening process, it allows for more precise control as the fastener approaches its seat, preventing unnecessary damage to the material.

[0063] While the two modes mentioned above can provide effective solutions in specific working environments, manually switching between them is still necessary when using an impact screwdriver. This not only increases operational complexity but can also lead to reduced efficiency or compromised work quality due to improper operation. Furthermore, the manual mode switching process can distract the operator, increasing safety hazards during operation. In fast-paced work environments, this manual switching method clearly cannot meet the requirements of high efficiency and high precision.

[0064] Therefore, there is an urgent need for a power tool that can automatically identify the working environment and intelligently switch control modes to improve the level of automation, reduce human intervention, and enhance the user experience and work safety.

[0065] This application provides an electric tool and its control method to improve upon the problems in related technologies where tools require pre-switching to a corresponding control mode during operation, resulting in high operational complexity and low work efficiency. The electric tool may include an electric drill, impact drill, screwdriver, etc. As shown in Figure 1, the electric tool may include:

[0066] Output shaft 1 is used to output torque;

[0067] Housing 2, used to house the motor;

[0068] Motor 3 is used to drive the output shaft to rotate;

[0069] A transmission assembly (not shown in the figure) is used to connect the motor and the output shaft;

[0070] A current detection unit, used at least to detect the current when the power tool is running.

[0071] In an alternative embodiment, the current sensing unit can be configured as a current sensing resistor, a current sensor, etc.

[0072] The controller includes a processing unit and a storage unit;

[0073] Storage unit, used to store control instructions;

[0074] The processing unit is used to execute control commands to implement the control method of the power tool.

[0075] Figure 2 shows a schematic block diagram of a specific example of a power tool according to an embodiment of this application. As shown, the controller 303 is connected to the start button 302 and the current sensor 301 to acquire the power tool start signal and operating current parameters.

[0076] The execution steps of the power tool control method mentioned in this embodiment are shown in Figure 3, including the following steps:

[0077] S101, acquire the current value during the operation of the power tool;

[0078] As shown in the control method logic diagram in Figure 4, when the controller detects that the tool switch is closed, the controller controls the current detection unit to start acquiring the load current when the power tool is working. In this embodiment, the controller uses the current detection unit to sample the working current of the tool to obtain the load current data I.

[0079] In some alternative implementations, the current during tool operation can be sampled at fixed time intervals, such as storing a current data point every 5ms.

[0080] In some possible implementations, the initial current data can be further processed using averaging algorithms. Averaging algorithms include arithmetic average, moving average, and weighted average algorithms. Averaging the load current parameters and storing them at appropriate time intervals helps eliminate sudden current changes, thus providing more reliable current parameters. It also facilitates the storage of current values ​​in the controller and the subsequent calculation of current parameters.

[0081] S102, calculate the rate of change of current based on the current value;

[0082] In this embodiment, the rate of change of current is calculated using the method of successive differences. Specifically, the formula for the rate of change of current with respect to time is: ΔI=(I n -I m ) / (nm)

[0083] Where n and m are the current sampling time points at two fixed time intervals, I n and I m These are the current values ​​collected at times n and m, respectively; in this embodiment, 50ms is taken as a fixed time interval, and the formula for calculating the rate of change of current is: ΔI=(I n -I n-50 ) / 50

[0084] In some alternative implementations, other time intervals can be used to calculate the rate of change of current; at the same time, the method for calculating the rate of change of current can also be other methods such as slope formulas and derivative formulas.

[0085] S103, when the current change rate is greater than or equal to the current change rate threshold, the fastener is determined to begin to be seated;

[0086] In this embodiment, the current change curve of the power tool when screwing the fastener into the wooden board is shown in Figure 5. The time period t1 in the figure corresponds to the start-up phase of the power tool. As the workpiece begins to be screwed into the metal plate, the power tool enters the t2 time period, and the working current of the tool stabilizes at 11A. During this time period, the fastener is continuously screwed into the workpiece. Then, in the t3 time period, the fastener begins to settle into the wooden board. Due to the rapid increase in load torque, the working current increases to about 20A. The current rises by about 9A in less than 50ms, and the current change rate exceeds 0.18.

[0087] Figure 6 shows the current variation curve when the screw is screwed into the metal plate. The time period t1 in the figure corresponds to the start-up phase of the power tool. As the workpiece begins to be screwed into the metal plate, the power tool enters the t2 time period, and the tool's operating current stabilizes at 11.6A. During this time period, the fastener is continuously screwed into the workpiece. Then, in the t3 time period, the fastener begins to settle into the metal plate. Due to the rapid increase in load torque, the operating current rapidly increases to about 27A. The current rises by about 15A in less than 50ms, and the current change rate exceeds 0.3.

[0088] Considering the rate of change of current when the fastener begins to settle under both operating conditions, a preset current rate of change threshold is required to ensure that the fastener settling can be detected under both conditions. Therefore, in this embodiment, the current rate of change threshold a = 0.15 is set.

[0089] In some possible implementations, the current change rate threshold condition can be set to other values ​​or forms. For example, the current change rate threshold can be set as a threshold range, and when the current change rate is within the threshold range, the fastener seating condition is considered to be met.

[0090] As shown in the control method logic diagram in Figure 4, the current current change rate ΔI is compared with the change rate threshold a. When a = 0.15, if ΔI < 0.15, it is considered that the fastener has not yet been seated, and the controller continues to monitor the load current; if ΔI ≥ 0.15, it is determined that the fastener has begun to be seated.

[0091] When the fastener begins to settle, the resistance to the workpiece suddenly increases, causing the load current of the tool to rise rapidly. Therefore, judging the fastener's settling by calculating the rate of change of current is less affected by fluctuations in the magnitude of the current and can further improve the accuracy of judging the fastener's settling.

[0092] S104 detects the average current within a preset time after the fastener is seated, compares the average current with the current threshold, and determines the workpiece type based on the comparison result.

[0093] The preset time period after the fastener begins to be seated is a time period starting from the moment the fastener begins to be seated. In this embodiment, a 5ms time period starting from the moment t when the fastener begins to be seated is used as the preset time period. The average current I within the preset time period is calculated and obtained. t .

[0094] In some possible implementations, the current parameter within the preset time period can also be other parameter values ​​such as the maximum current value or the median current value.

[0095] In this embodiment, as shown in Figures 5 and 6, after the fastening process enters stage t3 and the fastener begins to settle, the operating current of the power tool rises rapidly and is significantly higher than the operating current under normal tightening conditions. In Figure 5, when the fastener acts on the wooden board, entering stage t3, the operating current rises to approximately 20A. In Figure 6, when the fastener acts on the metal plate, entering stage t3, the operating current rises to approximately 27A. It can be seen that the current during settling is related to the hardness or softness of the workpiece.

[0096] The following are the current data for the number of fasteners initially seated on the workpiece, obtained from multiple tests conducted by the user using a standardized screwdriver on wooden and metal plates:

[0097] Combining Figures 5 and 6 with the current data in the table above, it can be seen that when the workpiece type is a wooden board, the current generally rises and remains below 20A after the fastener begins to sit; when the workpiece type is a metal plate, the current rises to over 25A after the fastener begins to sit. Therefore, the current threshold in this embodiment must at least be greater than 20A and less than 25A. Preferably, in this embodiment, the current threshold b = 23.

[0098] Based on this, as shown in Figure 4, I t Compare with the current threshold b, since b = 23. If I t If the value is less than or equal to 23, the workpiece type is determined to be a wooden board, and the wooden board operation mode is executed; if I t If the value is greater than or equal to 23A, the workpiece type is determined to be a metal plate, and the metal operation mode is executed.

[0099] S105, depending on the workpiece type, execute either the metal operation mode or the wooden board operation mode.

[0100] As shown in logic diagram 4, if the workpiece type is determined to be a wooden board, the wooden board operation mode is executed, and the control tool runs at a lower duty cycle to maintain the tool at a low speed. In this embodiment, in the wooden board operation mode, the controller controls the power tool to run at a 15% duty cycle;

[0101] In some possible implementations, when the controller executes the board operation mode, the rotation method controlled by the power tool can also be other methods that help the fastener to be placed smoothly and accurately, including: constant speed control; intermittent forward rotation at arbitrary time intervals, i.e., there is an arbitrary time interval between each two forward rotations, etc.

[0102] As shown in logic diagram 4, if the workpiece type is determined to be a metal sheet, the metal operation mode is executed, and the power tool is immediately stopped. The methods for controlling the immediate stop include power cut-off and braking.

[0103] In this embodiment, when the user drives the fastener into the wooden or plasterboard, due to the softness of the workpiece material, if the tool is not stopped in time, the screw can easily be driven too deeply into the wooden / plasterboard, or even damaged by penetration. Using the control method described above can effectively avoid this problem. Simultaneously, to ensure the fastener is roughly flush with the workpiece surface, it needs to continue rotating for a period of time after the fastener begins to settle on the wooden / plasterboard surface, ensuring complete settling. Therefore, in wooden board operation mode, the controller controls the tool to continue running at a low speed / low duty cycle after the fastener begins to settle, making it easier to drive the fastener into the appropriate position in the wooden / plasterboard while preventing damage to the workpiece. In metal operation mode, due to the higher hardness of the metal plate, the controller controls the tool to stop immediately after settling to prevent overtightening, screw stripping, or damage to the workpiece.

[0104] In one optional embodiment, the power tool housing is provided with a user display interface, which displays the currently activated operating mode after the wood or metal operating mode is activated. The user interface can be an LED light, a liquid crystal display (LCD), an LED display, or an OLED display, etc.

[0105] The power tool and its control method provided in this invention first determine whether the fastener is seated by calculating the current slope value, then distinguish the workpiece type by comparing the current magnitude after initial seating, avoiding the inaccuracy of judging the workpiece type solely by the current slope, and finally execute different operation modes according to the workpiece type, avoiding the problem of users needing to frequently manually switch tool modes when facing complex working conditions.

[0106] This application also provides a control method for power tools. Figure 7 shows a schematic diagram of another specific example of the control method for power tools in this application. As shown in the figure, the control method may include the following steps:

[0107] S201, Obtain the current value during the operation of the power tool;

[0108] S202, calculate the rate of change of current based on the current value;

[0109] S203, when the rate of change of current is greater than or equal to the threshold of the rate of change of current, the fastener is determined to begin to be seated;

[0110] In this embodiment, the specific details of steps S201-S203 can be referred to steps S101-S103 in the control method described above, and will not be repeated here.

[0111] S204, control tools immediately reduce speed;

[0112] As shown in logic diagram 8, after determining that the fastener has begun to settle, the controller immediately controls the tool to reduce its speed. In this embodiment, the current variation curves of the power tool driving the fastener into the wooden board and metal plate are shown in Figures 9 and 10, respectively. During the t1-t3 stages in Figures 9 and 10, the tool gradually screws the fastener into the workpiece. Until the t3 stage, the controller recognizes that the fastener has begun to settle into the workpiece and then immediately controls the tool to reduce its speed. In this embodiment, the voltage duty cycle is reduced to 10%, causing the power tool to slow down. Therefore, during the t4 stage in Figures 9 and 10, the tool's operating current is low.

[0113] In an alternative implementation, the method for immediately reducing the speed of the tool can also be any other way of reducing the tool output, such as braking or constant speed control; it should be noted that the above-described speed reduction method will not cause the tool to stop completely in steps S204 and S205.

[0114] S205: While performing the deceleration operation, detect the peak current generated after the tool decelerates, compare the detected peak current with the peak current threshold, and determine the workpiece type based on the comparison result.

[0115] Because the tool speed decreases after stage t3 in Figures 9 and 10, the current, which was increasing in stage t3, suddenly drops, resulting in a current spike between stages t3 and t4. In Figure 9, the spike current value is 18A when the workpiece is a wooden board; when the workpiece material is a metal plate, as shown in Figure 10, the spike current value is 26A. The following are the spike current test data obtained by repeatedly tightening screws on wooden and metal plates using a screwdriver of uniform specifications:

[0116] As can be seen from the above, the magnitude of the peak current also mainly depends on the hardness of the workpiece. When the workpiece is a wooden board, the measured peak current does not exceed 19A; when the workpiece is a metal plate, the measured peak current exceeds 25A. Therefore, the peak current threshold in this embodiment must be at least greater than 19A and less than 25A. Preferably, the current threshold b of this invention is 22A.

[0117] S206, depending on the workpiece type, execute either the metal operation mode or the wooden board operation mode.

[0118] As shown in logic diagram 8, if the workpiece type is determined to be a wooden board, the wooden board operation mode is executed, and the control tool runs at a low duty cycle to maintain the tool at a low speed. In this embodiment, in the wooden board operation mode, the controller controls the power tool to run continuously at a 15% duty cycle;

[0119] In one alternative implementation, the controller can control the rotation mode performed by the power tool in the plank operation mode, as well as other modes that help the fastener to be placed more smoothly and accurately, including: constant speed control; intermittent forward rotation at arbitrary time intervals, i.e., there is an arbitrary time interval between every two forward rotations; and reversal at arbitrary time intervals between every two forward rotations, with the total forward rotation time being greater than the total reversal time.

[0120] As shown in flowchart 8, if the workpiece type is determined to be a metal plate, the tool output duty cycle is reduced to 0, or a control method such as braking is adopted to stop the motor immediately.

[0121] Figure 11 shows a schematic block diagram of a specific example of the controller in an embodiment of this application. As shown, the controller may include a processor and a memory, the processor being connected to the memory, the memory storing control instructions, and the processor calling the control instructions stored in the memory to implement at least one control method for a power tool as described in the above embodiments and / or other desired functions.

[0122] A processor can be a circuit with signal processing capabilities. In one implementation, a processor can be a circuit with instruction read and execute capabilities, such as a Central Processing Unit (CPU), a microprocessor, a graphics processing unit (GPU) (which can be understood as a type of microprocessor), or a digital signal processor (DSP). In another implementation, a processor can implement certain functions through the logical relationships of hardware circuits. These logical relationships of hardware circuits are fixed or reconfigurable. For example, a processor is a hardware circuit implemented using an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), such as an FPGA. In a reconfigurable hardware circuit, the process of the processor loading a configuration document and configuring the hardware circuit can be understood as the processor loading instructions to implement the functions described by those instructions. Furthermore, it can also be a hardware circuit designed for artificial intelligence, which can be understood as a type of ASIC, such as a Neural Network Processing Unit (NPU), a Tensor Processing Unit (TPU), or a Deep Learning Processing Unit (DPU). The controller can be implemented entirely through processor-invoked software, entirely through hardware circuitry, or partially through processor-invoked software with the remainder implemented through hardware circuitry.

[0123] The memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor may execute the program instructions to implement the functions of the controller and / or other desired functions.

[0124] The controller may also include a network interface, a display, and input devices connected via a system bus. The network interface can be used to communicate with external terminals via a network connection. The display can be an LCD or an e-ink display. The input devices can be a touch layer covering the display, buttons, a trackball, or a touchpad, or an external keyboard, touchpad, or mouse, etc.

[0125] This specification provides method operation steps as shown in the embodiments or flowcharts, but based on conventional or non-inventive labor, more or fewer operation steps may be included. The order of steps listed in the embodiments is merely one possible execution order among many and does not represent the only execution order. In actual devices, systems, or server products, the methods shown in the embodiments or drawings can be executed sequentially or in parallel (e.g., in a parallel processor or multi-threaded processing environment).

[0126] It should be understood that the above embodiments are exemplary and are not intended to encompass all possible implementations included in the claims. Various modifications and changes can be made to the above embodiments without departing from the scope of this disclosure. Similarly, the various technical features of the above embodiments can be arbitrarily combined to form other embodiments of this application that may not be explicitly described. Therefore, the above embodiments only illustrate several implementations of this application and do not limit the scope of protection of this patent application.

Claims

1. A control method for an electric tool, characterized in that, The control method includes: Obtain the rate of change of current during tool operation; The current change rate is used to determine whether the fastener being acted upon by the power tool has begun to sit; when it is determined that the fastener has begun to sit, the current parameters within a preset time period are obtained. A control command is generated based on the current parameters, and the control command is used to put the power tool into a first operating mode or a second operating mode.

2. The control method for power tools according to claim 1, characterized in that, The step of determining whether the fastener operated by the power tool has begun to settle based on the rate of change of current includes: If the current change rate is greater than or equal to the current change rate threshold, then it is determined that the fastener operated by the power tool has begun to sit.

3. The control method for power tools according to claim 2, characterized in that, The preset time period is a period of time starting from the moment the fastener begins to be seated; the current parameter is the average current value within the preset time period.

4. The control method for power tools according to claim 3, characterized in that, The step of generating control commands based on the current parameters includes: If the average current is less than the average current threshold, a first control command is output to cause the power tool to enter a first operating mode, which is a wooden board operating mode.

5. The control method for power tools according to claim 4, characterized in that, The step of generating control commands based on the current parameters includes: If the average current is greater than or equal to the average current threshold, a second control command is output to cause the power tool to enter a second operating mode, which is a metal operating mode. The average current threshold is between the average current of the power tool when it is applied to the wooden board during the preset time period and the average current of the power tool when it is applied to the metal plate during the preset time period.

6. The control method for power tools according to claim 2, characterized in that, The step of the fastener starting to sit includes: The power tool slows down and acquires the peak current generated by the slowdown within a preset time period; the preset time period is a period of time starting from the beginning of the fastener being seated and ending at a point in time after the power tool slows down.

7. The control method for power tools according to claim 6, characterized in that, The step of generating control commands based on the current parameters includes: If the peak current is less than the peak current threshold, a first control command is output to cause the power tool to enter a first operating mode, which is a wooden board operating mode.

8. The control method for power tools according to claim 7, characterized in that, The step of generating control commands based on the current parameters includes: If the peak current is greater than or equal to the peak current threshold, a second control command is output to cause the power tool to enter a second operating mode, which is a metal operating mode. The peak current threshold is between the peak current of the power tool when the fastener is placed on the wooden board and the peak current of the power tool when the fastener is placed on the metal plate.

9. The control method for an electric tool according to any one of claims 1-8, wherein when the electric tool enters the first operating mode, a third control command is executed, the third control command being used to reduce the speed of the electric tool; and when the electric tool enters the second operating mode, a fourth control command is executed, the fourth control command being used to stop the electric tool.

10. A power tool for driving fasteners into a workpiece, the power tool comprising: The output shaft is used to output torque. Housing for accommodating the motor; An electric motor is used to drive the output shaft to rotate; A transmission assembly, which connects the motor and the output shaft; A current detection unit is used at least to detect the current during operation of the power tool; The power tool is characterized in that it further includes: Controller; the controller includes a processing unit and a storage unit; The aforementioned storage unit is used to store control instructions; The processing unit is configured to execute the control instructions to implement the power tool control method as described in any one of claims 1 to 9.

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