Electric tool and control method thereof

Abstract

The invention discloses an electric tool and a control method thereof. The electric tool includes: a functional member; the operation part is operated by a user to select a currently adopted target working mode; the electric tool has at least two working modes; the motor is used for driving the functional part to work; the power supply device is at least used for supplying power to the motor; the driving device is connected with the motor and the power supply device and used for driving the motor to operate; the controller is connected with the operating part and the driving device and is used for outputting a control signal to the driving device so as to control the driving device; wherein the controller is configured to determine a target switching condition for switching a control mode of the motor in a target working mode according to the target working mode currently adopted by the electric tool; the switching conditions for switching the control modes of the motor in different working modes are different; and under the condition that the target switching condition is met, switching the control mode of the motor from a first target control mode in the target working mode to a second target control mode.

Description

Technical Field

[0001] The present application relates to the technical field of electric tools, and in particular to an electric tool and a control method thereof. Background Art

[0002] Power tools are powered by motors for cutting, grinding, fastening and other operations. They are convenient and efficient, and can help operators significantly reduce labor intensity. They are widely used in many fields such as construction, decoration, gardening, and automobiles. The motors that drive the functional parts of power tools are mostly controlled by controllers in a single control mode. However, in some scenarios, the working conditions faced by power tools are mostly complex. At this time, if the motor is still controlled in a single way, it will not be able to adapt to the changes in working conditions, which will have a negative impact on the working efficiency and user experience of the power tools.

[0003] This section provides background information related to the present application which is not necessarily prior art. Summary of the invention

[0004] One object of the present application is to solve or at least alleviate part or all of the above problems. To this end, one object of the present application is to provide an electric tool and a control method thereof.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] An electric tool comprises: a functional part; an operating part for a user to operate to select a target working mode currently adopted; the electric tool has at least two working modes; a motor for driving the functional part to perform operation;

[0007] A power supply device is at least used to supply power to the motor; a drive device is connected to the motor and the power supply device and is used to drive the motor to operate; a controller is connected to the operating member and the drive device and is used to output a control signal to the drive device to control the drive device; wherein the controller is configured to: determine a target switching condition for switching the control method of the motor under a target working mode according to the target working mode currently adopted by the power tool; the switching conditions for switching the control method of the motor under different working modes are different; when the target switching condition is met, the control method of the motor is switched from the first target control method under the target working mode to the second target control method.

[0008] In some embodiments, the controller is configured to: when the target operating mode is the first operating mode and the first switching condition corresponding to the first operating mode is met, switch the control mode of the motor from the first control mode to the second control mode; when the target operating mode is the second operating mode and the second switching condition corresponding to the second operating mode is met, switch the control mode of the motor from the third control mode to the fourth control mode.

[0009] In some embodiments, the power tool also includes: a parameter detection device, connected to the controller, configured to detect one or more motor parameters of the motor and output the detected motor parameters to the controller; the controller is configured to use the target motor parameter corresponding to the target working mode exceeding the target switching threshold corresponding to the target working mode as the target switching condition under the target working mode.

[0010] In some embodiments, the power tool also includes: a parameter detection device, connected to the controller, configured to detect multiple motor parameters of the motor and output the detected motor parameters to the controller; the controller is configured to use any target motor parameter among the multiple target motor parameters corresponding to the target working mode exceeding the target switching threshold corresponding to the target motor parameter under the target working mode as a target switching condition under the target working mode.

[0011] In some embodiments, the power tool also includes: a parameter detection device, connected to the controller, configured to detect multiple motor parameters of the motor and output the detected motor parameters to the controller; the controller is configured to use the multiple target motor parameters corresponding to the target working mode all exceeding the target switching thresholds corresponding to the target motor parameters under the target working mode as the target switching conditions under the target working mode.

[0012] In some embodiments, the motor parameters used as switching conditions by the controller in different working modes are the same, and the switching thresholds corresponding to the motor parameters are different.

[0013] In some embodiments, the motor parameters used as switching conditions by the controller in different working modes are different, and the switching thresholds corresponding to the motor parameters are different.

[0014] In some embodiments, the motor parameters include one or more of motor speed, bus current, phase current, demagnetization time, MOS temperature, battery pack temperature, and battery pack voltage.

[0015] In some embodiments, the motor is a brushless motor; the first target control mode and the second target control mode are two different control modes among a six-step commutation control mode, a FOC control mode, and a sinusoidal transformation control mode.

[0016] In some embodiments, the operating modes of the power tool include a wood mode and a metal mode.

[0017] In some embodiments, the motor has different speeds and / or torques in different operating modes.

[0018] A control method for an electric tool, comprising: a controller determines a target switching condition for switching the control mode of a motor under a target working mode according to a target working mode currently adopted by the electric tool; the electric tool has at least two working modes; and when the target switching condition is met, the controller switches the control mode of the motor from a first target control mode under the target working mode to a second target control mode.

[0019] The benefit of the present application lies in that the controller determines the switching conditions of the motor control method corresponding to the working mode based on the working mode currently adopted by the power tool. It not only switches the control method of the motor based on whether the switching conditions are met, but also switches the control method of the motor based on different switching conditions in different working modes. This allows the power tool to face different working conditions and operate in different working modes. It can drive the motor to operate in a control method that is suitable for the working conditions and working mode characteristics, effectively improving the efficiency of the motor and the tool and enhancing the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a three-dimensional diagram of a power tool as an embodiment of the present application;

[0021] Figure 2 yes Figure 1 The electrical control schematic diagram of the controller, drive device and motor in the electric tool shown;

[0022] Figure 3 yes Figure 1 The controller in the electric tool shown adopts a six-step phase-commutation control method to drive the electric control principle diagram of the motor;

[0023] Figure 4 yes Figure 1 The controller in the electric tool shown adopts FOC control method to drive the electric control principle diagram of the motor;

[0024] Figure 5 yes Figure 2 The flowchart of the controller switching the motor control mode shown;

[0025] Figure 6 yes Figure 2 Another flow chart of the controller switching the motor control mode;

[0026] Figure 7 yes Figure 2 Another flow chart of the controller switching the motor control mode shown;

[0027] Figure 8 yes Figure 2 Another flow chart of the controller switching the motor control mode shown;

[0028] Fig. 9 yes Figure 2 Another flow chart of the controller switching the motor control mode shown;

[0029] Fig.10 is a three-dimensional diagram of an electric drill used as an embodiment of the present application;

[0030] Fig.11 is a three-dimensional diagram of an electric wrench as an embodiment of the present application;

[0031] Fig.12 is a perspective view of a jigsaw used as an embodiment of the present application;

[0032] Fig.13 It is a flow chart of a control method of an electric tool as an embodiment of the present application. DETAILED DESCRIPTION

[0033] Before any embodiments of the application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the above drawings.

[0034] In this application, the terms "comprises", "includes", "has" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0035] In this application, the term "and / or" is a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects before and after are in an "and / or" relationship.

[0036] In the present application, the terms "connect", "combine", "couple", and "install" may refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, direct connection refers to two parts or components being connected together without the need for an intermediate piece, and indirect connection refers to two parts or components being connected to at least one intermediate piece respectively, and the two parts or components being connected via the intermediate piece. In addition, "connect" and "couple" are not limited to physical or mechanical connections or couplings, and may include electrical connections or couplings.

[0037] In the present application, it will be understood by those of ordinary skill in the art that relative terms (e.g., "about," "approximately," "substantially," etc.) used in conjunction with quantities or conditions include the values ​​and have the meaning indicated by the context. For example, the relative terms include at least the degree of error associated with the measurement of a specific value, the tolerances caused by manufacturing, assembly, and use associated with a specific value, and the like. Such terms should also be considered to disclose a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to plus or minus a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​that do not use relative terms should also be disclosed as specific values ​​with tolerances. In addition, "substantially" may refer to plus or minus a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) on the basis of the indicated angle when expressing a relative angular position relationship (e.g., substantially parallel, substantially perpendicular).

[0038] In this application, it will be understood by those skilled in the art that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0039] In the present application, the terms "upper", "lower", "left", "right", "front", "back" and other directional words are described based on the orientation and positional relationship shown in the accompanying drawings, and should not be understood as limiting the embodiments of the present application. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element. It should also be understood that directional words such as upper side, lower side, left side, right side, front side, back side, etc. not only represent the positive orientation, but can also be understood as the lateral orientation. For example, the bottom can include directly below, lower left, lower right, lower front, and lower back, etc.

[0040] In this application, the terms "controller", "processor", "central processing unit", "CPU", and "MCU" are interchangeable. When a unit "controller", "processor", "central processing unit", "CPU", or "MCU" is used to perform a specific function, unless otherwise specified, these functions can be performed by a single unit or multiple units.

[0041] In the present application, the terms “device”, “module” or “unit” may be implemented in the form of hardware or software to achieve specific functions.

[0042] In this application, the terms "calculate", "judge", "control", "determine", "identify", etc. refer to the operations and processes of a computer system or similar electronic computing device (e.g., controller, processor, etc.).

[0043] The technical solution proposed in this application is described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] Figure 1 An electric tool 100 is shown as one embodiment in the present application. Figure 1 The electric tool 100 shown may be a reciprocating saw 100a, and the electric tool 100 in other embodiments may also be other types of handheld electric tools 100b such as an electric drill, an electric circular saw, an impact wrench, or a bench-type tool 100c such as a miter saw or a table saw, or a walking garden tool 100d such as a lawn mower. It is understandable that the electric tool is not limited to the categories described above, and any electric tool that is driven by a motor and has at least two working modes can apply the technical solution proposed in this application, such as a blender.

[0045] The power tool 100 in the present application has at least two working modes. Different working modes can be artificially set and distinguished. For example, the two different working modes can be a first working mode belonging to user A and adapted to the use habits of user A, and a second working mode belonging to user B and adapted to the use habits of user B. Different working modes can also be set and distinguished based on the difference in relevant physical properties. For example, considering the different characteristics of the motor speed, torque, etc. when facing different cutting materials, saw tools can be set with wood mode and metal mode, or the power tool 100 can simply be set with a low-speed high-torque saw and a high-speed low-torque mode.

[0046] refer to Figure 1 The electric tool 100 includes a housing 10, an operating member 20, a functional member 30 and a power supply device 40. The housing 10 constitutes the main body of the electric tool 100, which connects or supports the operating member 20, the functional member 30 and the power supply device 40, and forms a receiving space. The motor 50 and the drive device 60 and the controller 70 to be described later are received in the receiving space of the housing 10. The operating member 20 can be operated by the user to start or stop the electric tool 100, and can be operated by the user to select the working mode of the electric tool 100 described above. The working mode selected by the user operating the operating member 20 is the target working mode currently adopted by the electric tool 100, which is one of the multiple working modes of the electric tool 100. The operating member 20 is structurally connected to the housing 10, and can be a mechanical switch or a signal switch, etc. In some embodiments, after being operated by the user, the operating member 20 can transmit a mode signal corresponding to the target working mode selected by the user to the controller 70 to be described later, so that the controller 70 can identify the target working mode currently adopted by the electric tool 100.

[0047] The functional part 30 is a part of the power tool 100 that actually works. It can be a cutting part such as a saw blade, or a fastener, a grinding part, an impact part, etc. It is structurally connected to the output shaft of the power tool 100. When the motor 50 shaft rotates, it can directly or indirectly drive the output shaft to rotate through a transmission component to drive the functional part 30 connected to the output shaft to complete related operations such as cutting, fastening, and grinding. The power supply device 40 at least supplies electrical energy to the motor 50 to be described later to drive its operation. Of course, the power supply of the drive device 60 and the controller 70 can also be undertaken by the power supply device 40. In some embodiments, the power supply device 40 can be a battery pack, which is detachably connected to the housing 10. In other embodiments, the power supply of the power tool 100 can also be achieved using AC power or AC power, in conjunction with a power adapter or related circuits such as transformer, rectifier, and voltage regulator.

[0048] refer to Figure 2 , the electric tool 100 also includes a motor 50, a drive device 60 and a controller 70. The motor 50 is a prime mover in the electric tool 100 that provides power for the operation of the functional part 30. The specific operation process of the motor 50 is controlled by the controller 70. The motor 50 is electrically connected to the drive device 60 and the controller 70, so that the control signal from the controller 70 is transmitted to the motor 50 through the drive device 60 to drive the motor 50 to operate. The control signal output by the controller 70 corresponds to the control method it adopts. In the present application, the controller 70 has at least two control methods for driving the motor 50. In some cases, the specific control method adopted by the controller 70 is also related to the presence or absence of a position sensor for locating the rotor position of the motor 50 in the electric tool 100.

[0049] In some embodiments, the motor 50 is a brushless motor 50, specifically, a three-phase brushless DC motor 50, and its control method includes but is not limited to a six-step commutation control method, a FOC control method, and a sine conversion control method. The drive device 60 may include a drive circuit such as a three-phase inverter bridge, and in some cases, it may also be an integrated drive chip. Taking the drive circuit with a three-phase inverter bridge as the core as an example, the drive device 60 can receive six control signals from the controller 70 and output corresponding three-phase signals to the motor 50. The three-phase signals are sinusoidal wave signals of the same frequency and amplitude with phase angles that differ by 120°.

[0050] For example, if Figure 3As shown, the controller 70 in the power tool 100 can use a six-step commutation control method to control the motor 50. The controller 70 can output six control signals to the drive device 60. The control signal output by the controller 70 in the six-step commutation method is a square wave signal or a trapezoidal wave signal, which can sequentially connect the two switch tube elements in the three-phase inverter bridge so that the drive device 60 finally outputs an approximate three-phase signal. The six-step commutation control method has the advantages of being convenient, easy to control, and having low heat consumption. For example, Figure 4 As shown, the controller 70 in the power tool 100 can also use FOC (Field-Oriented Control, also known as vector control) control mode to control the motor 50. The controller 70 can still output six control signals to the drive device 60. The control signal output by the controller 70 in the FOC mode is a sine wave signal. The drive device 60 can output a more accurate three-phase signal in the FOC control mode. The FOC control method has the advantages of precision, high efficiency and high torque. It is understandable that the control method of the motor 50 may also include other control methods not shown above depending on the application scenario of the power tool 100 and the requirements of specific working conditions.

[0051] The controller 70 includes a processor 71 and a memory 72. The processor 71 may be an MCU (Microcontroller Unit), an ARM (Advanced Reduced Instruction Set Computing Machine), a DSP (Digital Signal Processor), etc., and the memory 72 may be a ROM (Read-Only Memory), a RAM (Random Access Memory), a FLASH (FLASH EEPROM), and a combination thereof. The memory 72 stores a control program executable by the processor 71, and the processor 71 may read and run the control program in the memory 72 to control the motor 50.

[0052] The controller 70 is electrically connected to the driving device 60 and can output a control signal corresponding to the current control mode to the driving device 60 after running the control program. The controller 70 can also be electrically connected to the operating member 20 to determine the target working mode currently adopted by the power tool 100 by receiving a mode signal from the operating member 20 or the like.

[0053] In order to ensure that the power tool 100 always adopts a suitable control method to control the motor 50, so that the motor 50 can meet the mode requirements and operate efficiently under different working modes and different working conditions, the controller 70 will first determine the target working mode currently adopted by the power tool 100 before controlling the motor 50 to start operating. In some cases, the controller 70 determines the target working mode selected by the user by receiving a mode signal from the operating part 20. In other cases, the target working mode currently adopted by the power tool 100 is detected and switched by the controller 70, and the controller 70 can directly or indirectly determine the current target working mode through relevant parameters.

[0054] After determining the target working mode, the controller 70 will determine the first target control mode and the second target control mode that can be used when controlling the motor 50 under the target working mode according to the target working mode, as well as the target switching condition for switching the control mode of the motor 50 under the target working mode. In some embodiments, the controller 70 can run the same set of control programs to control the motor 50, and it will query the corresponding target switching conditions and the first and second target control modes according to the target working mode, and change the switching conditions currently used in the control program to the target switching conditions when running the control program, and use the first and second target control modes respectively depending on whether the switching conditions are met. The memory 72 can store the mapping relationship between the working mode, the switching conditions and the control mode, wherein the switching conditions corresponding to different working modes are different, or the switching conditions and control modes corresponding to different working modes are different. In other embodiments, the controller 70 runs different control programs under different working modes to control the motor 50, and it will call the corresponding control program according to the target working mode, and the switching conditions in the control programs corresponding to different working modes are different, or the switching conditions and control modes in the control programs corresponding to different working modes are different.

[0055] When the target switching condition is met, the controller 70 switches the control mode of the motor 50 from the first target control mode under the target working mode to the second target control mode. In other words, when the target switching condition is not met, the controller 70 will use the first target control mode under the target working mode to control the motor 50; and when the target switching condition is met, the controller 70 will use the second target control mode under the target working mode to control the motor 50. Specifically, Figure 5As shown, assuming that the electric tool 100 has a first working mode and a second working mode, the controller 70, when determining that the working mode currently adopted by the electric tool 100 is the first working mode, if the first switching condition corresponding to the first working mode is not satisfied, then the motor 50 is controlled by the first control mode; if the first switching condition is satisfied, then the motor 50 is controlled by the second control mode. When the controller 70 determines that the working mode currently adopted by the electric tool 100 is the second working mode, if the second switching condition corresponding to the second working mode is not satisfied, then the motor 50 is controlled by the third control mode; if the second switching condition is satisfied, then the motor 50 is controlled by the third control mode. Among them, the first switching condition is different from the second switching condition, the first control mode is different from the second control mode, and the third control mode is different from the fourth control mode. However, whether the first control mode is the same as the third control mode or the fourth control mode, and whether the second control mode is the same as the third control mode or the fourth control mode is not specifically limited. In addition, the electric tool 100 may also have more working modes, and the implementation method of the controller 70 controlling the motor 50 in more working modes can be obtained by analogy based on the above description, and will not be repeated here.

[0056] In some embodiments, the power tool 100 also includes a parameter detection module, and the parameter detection device 80 is electrically connected to the motor 50 and the controller 70, and can detect the motor parameters such as the voltage, current, power, speed, torque, etc. of the motor 50, and transmit the detected motor parameters to the controller 70. In different embodiments, the types and quantities of motor parameters detected and transmitted by the parameter detection device 80 can be the same or different. In some embodiments, the parameter detection device 80 can also detect only one or more motor parameters corresponding to the target working mode currently adopted by the power tool 100 based on the target working mode.

[0057] In the controller 70, the motor parameters and their corresponding switching thresholds can be used to represent the switching conditions for switching the control mode of the motor 50. When the motor parameters exceed the corresponding switching thresholds, the switching conditions are considered to be met. In the controller 70, there is a mapping relationship between the working mode, motor parameters, switching thresholds, and control modes. The motor parameters and / or switching thresholds corresponding to different working modes are different, and the switching thresholds corresponding to different motor parameters are different. The control modes corresponding to different working modes can be the same or different. The motor parameters used as switching conditions include, but are not limited to, the bus current, phase current, motor speed, demagnetization time, and MOS temperature of the motor 50, as well as the battery pack temperature and battery pack voltage of the battery pack 40 and other related parameters related to the battery pack information. It can be understood that, depending on the type of power tool and the changes in actual scene requirements, the motor parameters used as switching conditions may also include other types of motor parameters not shown.

[0058] In some embodiments, Figure 6 As shown, a single motor parameter and its corresponding switching threshold can be used in the controller 70 to characterize the switching condition. The controller 70 can determine the target motor parameter corresponding to the target working mode and the target switching threshold corresponding to the target motor parameter in the current target working mode according to the target working mode currently adopted by the power tool 100. When the target motor parameter currently detected and transmitted by the parameter detection device 80 does not exceed the preset corresponding target switching threshold, the controller 70 can control the motor 50 in the first target control mode under the target working mode; when the target motor parameter exceeds the preset corresponding target switching threshold, the controller 70 can control the motor 50 in the second target control mode under the target working mode.

[0059] In one case, the types of motor parameters used as switching conditions in different working modes are the same, but the switching threshold values ​​corresponding to the motor parameters used as switching conditions in different working modes are different. For example, the bus current motor parameter can be used as a switching condition in different working modes, but the bus current has different values ​​when switching the control mode in different working modes. In another case, the types of motor parameters used as switching conditions in different working modes are different, and the switching threshold values ​​corresponding to each motor parameter used as switching conditions in different working modes are also different. For example, the bus current can be used as a switching condition in the first working mode, and the motor 50 speed can be used as a switching condition in the second working mode. Naturally, the bus current value when switching the control mode in the first working mode is different from the motor 50 speed value when switching the control mode in the second working mode.

[0060] In some embodiments, Figure 7 As shown, the controller 70 may also use multiple motor parameters and their corresponding switching thresholds to characterize the switching conditions. The controller 70 may also determine one or more target motor parameters corresponding to the target working mode and the target switching thresholds corresponding to each target motor parameter in the current target working mode according to the target working mode currently adopted by the power tool 100. When the multiple target motor parameters currently detected by the parameter detection device 80 do not exceed the preset corresponding target switching thresholds, the controller 70 may control the motor 50 using the first target control method under the target working mode; when any of the multiple target motor parameters exceeds the preset corresponding target switching threshold, the controller 70 may control the motor 50 using the second target control method under the target working mode.

[0061] In other embodiments, Figure 8As shown, when any target motor parameter among the multiple target motor parameters currently detected by the parameter detection device 80 still does not exceed the preset target switching threshold corresponding to it, the controller 70 can adopt the first target control method to control the motor 50; when multiple target motor parameters all exceed the preset target switching threshold corresponding to them, the controller 70 can adopt the second target control method to control the motor 50.

[0062] In some other embodiments, Fig. 9 As shown, when the number of target motor parameters that exceed the preset target switching threshold corresponding to them among the multiple target motor parameters currently detected by the parameter detection device 80 does not exceed the quantity threshold, the controller 70 can adopt the first target control method to control the motor 50; when the number of target motor parameters that exceed the preset target switching threshold corresponding to them among the multiple target motor parameters exceeds the quantity threshold, the controller 70 can adopt the second target control method to control the motor 50.

[0063] In one case, the types of multiple motor parameters used as switching conditions in different working modes are the same, but at least one of the values ​​of the switching thresholds corresponding to the multiple motor parameters used as switching conditions in different working modes is different. In another case, the types and / or quantities of motor parameters used as switching conditions in different working modes are different, and the switching thresholds corresponding to different types of motor parameters are different whether in the same working mode or in different working modes, and the switching thresholds corresponding to the same type of motor parameters in different working modes can be the same or different.

[0064] It is understandable that the controller 70 can also determine which control method should be used to control the motor 50 at the current moment based on multiple target motor parameters based on other more complex preset rules. For example, the controller 70 can calculate multiple target motor parameters based on a preset function, and compare them with a preset calculation threshold to determine which motor control method to use, wherein the calculation thresholds in different working modes can be different, or the operation functions and their calculation thresholds in different working modes can be different.

[0065] In the electric tool described above, the controller determines the switching conditions of the motor control method corresponding to the working mode based on the current working mode of the electric tool. The controller will not only switch the control method of the motor based on whether the switching conditions are met, but also switch the control method of the motor based on different switching conditions in different working modes. This allows the electric tool to drive the motor to operate in a control method that is suitable for the working conditions and the characteristics of the working mode when facing different working conditions and working modes, effectively improving the efficiency of the motor and the tool and enhancing the user experience.

[0066] In order to clarify the technical solution proposed in this application, a reciprocating saw 100a is introduced below.

[0067] by Figure 1 Taking the reciprocating saw 100a shown as an example, the reciprocating saw 100a has two working modes: wood mode and metal mode. The wood mode is used when cutting wood, and requires the motor 50 to have a high speed and strong anti-stall ability, while the metal mode is used when cutting metal, and requires the motor 50 to have a stable, low speed and a large torque. The user can operate the operating member 20 connected to the housing 10 of the reciprocating saw 100a to select one of the above two working modes.

[0068]

[0069] Table 1

[0070] When the controller 70 in the reciprocating saw 100a receives the mode signal from the operating member 20 and determines that the current working mode is the wood mode, Table 1 can be queried to determine whether the bus current exceeds 60A in the wood mode to switch between the FOC control mode and the six-step commutation control mode. When the bus current of the motor 50 is detected to be 15A, it means that it is currently in a light load state, and the controller 70 controls the motor 50 using the FOC control mode to increase the speed of the motor 50; when the bus current is detected to be 65A, it means that the motor 50 is currently in a heavy load state, and the controller 70 controls the motor 50 using the six-step commutation control mode to reduce the stall current and improve the anti-stall capability.

[0071] When the controller 70 in the reciprocating saw 100a determines that the current working mode is the metal mode, it can query Table 1 to determine whether the motor speed exceeds 1800RPM in the metal mode and switch between the FOC control mode and the six-step commutation control mode. When the current speed of the motor 50 is detected to be 1500RPM, it means that it is currently in a low-speed state, and the controller 70 uses the FOC control mode to control the motor 50 to increase the torque; when the motor speed is detected to be 2200RPM, it means that the motor 50 is currently in a high-speed state, and the controller 70 uses the six-step commutation control mode to control the motor 50 to reduce heat.

[0072] Next, another electric drill 100b will be introduced.

[0073] refer to Fig.10 Take the electric drill 100b shown as an example. The electric drill 100b has a screw mode and a steel plate drilling mode. The screw mode is used when tightening screws, while the steel plate drilling mode is used when drilling holes in metal sheets. The user can operate the operating member 20 connected to the housing 10 of the electric drill 100b to select one of the above two working modes.

[0074]

[0075] Table 2

[0076] When the controller 70 in the electric drill 100b receives the mode signal from the operating member 20 and determines that the current working mode is the screw mode, Table 2 can be queried to determine whether the bus current exceeds 40A in the screw mode to switch between the FOC control mode and the six-step commutation control mode. When the current bus current of the motor 50 is detected to be 30A, the controller 70 controls the motor 50 using the FOC control mode; when the bus current is detected to be 45A, the controller 70 controls the motor 50 using the six-step commutation control mode.

[0077] When the controller 70 in the electric drill 100b determines that the current working mode is the steel plate drilling mode, Table 2 can be queried to determine whether the motor speed exceeds 25000RPM in the steel plate drilling mode and whether to switch between the FOC control mode and the six-step commutation control mode. When the current motor speed of the motor 50 is detected to be 18000RPM, the controller 70 controls the motor 50 using the FOC control mode; when the motor speed is detected to be 28000RPM, the controller 70 controls the motor 50 using the six-step commutation control mode.

[0078] Next, an electric wrench 100c will be introduced.

[0079] by Fig.11 Taking the electric wrench 100c shown as an example, the electric wrench 100c has two working modes: a tightening mode and a loosening mode. The tightening mode is used when tightening a workpiece, while the loosening mode is used when loosening a workpiece. The user can operate the operating member 20 connected to the housing 10 of the electric wrench 100c to select one of the above two working modes.

[0080]

[0081]

[0082] Table 3

[0083] When the controller 70 in the electric wrench 100c receives the mode signal from the operating member 20 and determines that the current working mode is the tightening mode, Table 3 can be queried to determine whether the bus current exceeds 20A in the tightening mode to switch between the FOC control mode and the six-step commutation control mode. When the current bus current of the motor 50 is detected to be 15A, the controller 70 controls the motor 50 using the FOC control mode; when the bus current is detected to be 25A, the controller 70 controls the motor 50 using the six-step commutation control mode.

[0084] When the controller 70 in the electric wrench 100c determines that the current working mode is the loosening mode, Table 3 can be queried to determine whether to switch between the FOC control mode and the six-step commutation control mode in the loosening mode based on whether the motor speed exceeds 28000RPM. When the current motor speed of the motor 50 is detected to be 18000RPM, the controller 70 controls the motor 50 using the FOC control mode; when the motor speed is detected to be 30000RPM, the controller 70 controls the motor 50 using the six-step commutation control mode.

[0085] Next, another jigsaw 100d will be introduced.

[0086] refer to Fig.12 Taking the jigsaw 100d as an example, the jigsaw 100d has 6 working modes from 1 to 6. When using the 1st gear, the motor 50 is required to have a stable and low speed and a large torque, and less heat; when using the 6th gear, the motor 50 is required to have a high speed and strong anti-stalling ability. In addition, it is also required to extend the tool use time when the power is low. The user can operate the operating member 20 connected to the housing 10 of the jigsaw 100d to select any of the above gears.

[0087]

[0088] Table 4

[0089] When the controller 70 in the jigsaw 100d receives the mode signal from the operating member 20 and determines that the current working mode is gear 1, Table 4 can be consulted to determine whether to switch between the FOC control mode and the six-step commutation control mode in gear 1 based on whether the bus current exceeds 60A. When the current bus current of the motor 50 is detected to be 35A, the controller 70 controls the motor 50 using the FOC control mode; when the current bus current is detected to be 75A, the controller 70 controls the motor 50 using the six-step commutation control mode.

[0090] When the controller 70 in the jigsaw 100d determines that the current working mode is the 6th gear, it can query Table 4 to determine whether to switch between the FOC control mode and the six-step commutation control mode in the 6th gear mode based on whether the motor speed exceeds 2000RPM and whether the battery pack voltage exceeds 17V. When it is detected that the current motor speed of the motor 50 is 1500RPM and the battery pack voltage is 15V, the controller 70 controls the motor 50 using the FOC control mode; when it is detected that the motor speed is 2050RPM and the battery pack voltage is 16.8V, the controller 70 controls the motor 50 using the FOC control mode; when it is detected that the motor speed is 2200RPM and the battery pack voltage is 18V, the controller 70 controls the motor 50 using the six-step commutation control mode.

[0091] Correspondingly, Fig.13A flow chart of a method for controlling an electric tool as an embodiment of the present application is shown. Fig.13 The control method of the electric tool shown can be applied to any electric tool 100 described above, and the control method includes the following steps:

[0092] S1302, the controller 70 determines a target switching condition for switching the control method of the motor 50 in the target working mode according to the target working mode currently adopted by the power tool 100; the power tool 100 has at least two working modes;

[0093] S1304: When the target switching condition is satisfied, the controller 70 switches the control mode of the motor 50 from the first target control mode in the target working mode to the second target control mode.

[0094] In some embodiments, when the target operating mode is the first operating mode and the first switching condition corresponding to the first operating mode is met, the controller 70 switches the control mode of the motor 50 from the first control mode to the second control mode; when the target operating mode is the second operating mode and the second switching condition corresponding to the second operating mode is met, the controller 70 switches the control mode of the motor 50 from the third control mode to the fourth control mode.

[0095] In some embodiments, the parameter detection device 80 detects one or more motor parameters of the motor 50 and outputs the detected motor parameters to the controller 70; the controller 70 uses the target motor parameter corresponding to the target operating mode exceeding the target switching threshold corresponding to the target operating mode as the target switching condition under the target operating mode.

[0096] In some embodiments, the controller 70 uses the fact that any target motor parameter among a plurality of target motor parameters corresponding to the target operating mode exceeds a target switching threshold corresponding to the target motor parameter in the target operating mode as a target switching condition in the target operating mode.

[0097] In some embodiments, the controller 70 uses the fact that multiple target motor parameters corresponding to the target working mode all exceed the target switching thresholds corresponding to the target motor parameters in the target working mode as the target switching condition in the target working mode.

[0098] In some embodiments, the motor parameters used as switching conditions by the controller 70 in different working modes are the same, but the switching thresholds corresponding to the motor parameters are different.

[0099] In some embodiments, the controller 70 uses different motor parameters as switching conditions in different working modes, and the switching thresholds corresponding to the motor parameters are different.

[0100] In some embodiments, the motor parameters include one or more of motor speed, bus current, demagnetization time, MOS temperature, battery pack temperature, battery pack voltage, etc.

[0101] In some embodiments, the motor 50 is a brushless motor; the first target control mode and the second target control mode are two different control modes among a six-step commutation control mode, a FOC control mode, and a sinusoidal transformation control mode.

[0102] In some embodiments, the operating modes of the power tool 100 include a wood mode and a metal mode.

[0103] In some embodiments, the rotation speed and / or torque of the motor 50 is different in different operating modes.

[0104] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the above embodiments do not limit the present application in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present application.

Claims

1. An electric tool comprising: Functional parts; An operating element for the user to operate to select the currently used target working mode; The electric tool has at least two working modes; A motor, used to drive the functional parts to operate; A power supply device, at least used to supply power to the motor; A driving device, connected to the motor and the power supply device, and used to drive the motor to operate; A controller, connected to the operating member and the driving device, and configured to output a control signal to the driving device to control the driving device; Wherein, the controller is configured as: Determining a target switching condition for switching the control mode of the motor in the target working mode according to the target working mode currently adopted by the electric tool; the switching conditions for switching the control mode of the motor in different working modes are different; When the target switching condition is met, the control mode of the motor is switched from the first target control mode in the target working mode to the second target control mode.

2. The electric tool according to claim 1, wherein: The controller is configured to: when the target operating mode is the first operating mode and a first switching condition corresponding to the first operating mode is satisfied, switch the control mode of the motor from the first control mode to the second control mode; When the target operating mode is the second operating mode and a second switching condition corresponding to the second operating mode is satisfied, the control mode of the motor is switched from the third control mode to the fourth control mode.

3. The electric tool according to claim 1, wherein: The electric tool also includes: a parameter detection device, connected to the motor and the controller, configured to detect one or more motor parameters of the motor and output the detected motor parameters to the controller; the controller is configured to use the target motor parameter corresponding to the target working mode exceeding the target switching threshold corresponding to the target working mode as the target switching condition under the target working mode.

4. The electric tool according to claim 1, wherein: The electric tool also includes: a parameter detection device, connected to the motor and the controller, configured to detect multiple motor parameters of the motor and output the detected motor parameters to the controller; the controller is configured to use any target motor parameter among the multiple target motor parameters corresponding to the target working mode exceeding a target switching threshold corresponding to the target motor parameter under the target working mode as the target switching condition under the target working mode.

5. The electric tool according to claim 1, wherein: The electric tool also includes: a parameter detection device, connected to the motor and the controller, configured to detect multiple motor parameters of the motor and output the detected motor parameters to the controller; the controller is configured to use the multiple target motor parameters corresponding to the target working mode all exceeding the target switching thresholds corresponding to the target motor parameters under the target working mode as the target switching conditions under the target working mode.

6. The electric tool according to any one of claims 3 to 5, wherein: The motor parameters used as switching conditions of the controller in different working modes are the same, and the switching thresholds corresponding to the motor parameters are different.

7. The electric tool according to any one of claims 3 to 5, wherein: The controller uses different motor parameters as switching conditions in different working modes, and the motor parameters respectively correspond to different switching thresholds.

8. The electric tool according to any one of claims 3 to 5, wherein: The motor parameters include one or more of motor speed, bus current, phase current, demagnetization time, MOS temperature, battery pack temperature, and battery pack voltage.

9. The electric tool according to claim 1, wherein: The motor is a brushless motor; the first target control mode and the second target control mode are two different control modes among a six-step commutation control mode, a FOC control mode, and a sinusoidal transformation control mode.

10. The electric tool according to claim 1, wherein: The working modes of the electric tool include a wood mode and a metal mode.

11. The electric tool according to claim 1, wherein: The motor has different rotation speeds and / or torques in different working modes.

12. A method for controlling an electric tool, wherein: The method comprises: The controller determines a target switching condition for switching the control mode of the motor under the target working mode according to the target working mode currently adopted by the electric tool; the electric tool has at least two working modes; The controller switches the control mode of the motor from a first target control mode in the target working mode to a second target control mode when the target switching condition is met.

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