Electric tool

Abstract

The utility model relates to an electric tool. The electric tool provided by the embodiment of the utility model comprises a brake mode control switch which is configured to switch and / or adjust the brake mode of a motor of the electric tool; the braking modes comprise at least two of a first mode, a second mode and a third mode; under the condition of the first mode, the motor is controlled by a pulse width modulation signal with a 100% duty ratio to start braking until the motor is braked; under the condition of the second mode, the motor is controlled by the pulse width modulation signal with the first preset duty ratio to start braking until the motor is braked; the first preset duty ratio is smaller than 100% duty ratio; under the condition of the third mode, the motor is subjected to time-sharing control of the pulse width modulation signal with the 100% duty ratio and the pulse width modulation signal with the second preset duty ratio so as to be braked until the motor is braked; the second preset duty ratio is smaller than 100% duty ratio. According to the embodiment, a user can adjust the tool braking mode at will, and the user experience is improved.

Description

Technical Field

[0001] The present application relates to the field of electric tools, and in particular to a control technology for electric tools. Background Art

[0002] At present, some power tools (such as electric drills, etc.) usually have metal chucks, such as Figure 8 As shown, the metal chuck includes cylindrical pins 001 (e.g., 6 pins). When the switch is released and the motor of the power tool stops, the cylindrical pins 001 will continue to rotate for a short distance due to inertia, thereby colliding with the protruding pieces 002 (e.g., 3 pins) on the shaft lock frame and producing a knocking sound. The higher the motor speed, the louder the knocking sound from the metal chuck.

[0003] In terms of user experience, some users like the motor to stop quickly and make a loud impact sound after releasing the switch, and the louder the impact sound, the more "powerful" the user feels the power tool is; while some users prefer a smaller impact sound and a softer braking method. However, current power tools cannot allow users to easily and directly switch to the desired braking method, resulting in a poor user experience. Utility Model Content

[0004] In view of this, an embodiment of the present application provides an electric tool to solve at least one problem existing in the background technology.

[0005] An embodiment of the present application provides an electric tool, the electric tool comprising a brake mode control switch configured to switch and / or adjust the brake mode of the electric tool motor;

[0006] The braking method includes at least two of a first method, a second method and a third method;

[0007] In the case of the first mode, the motor is controlled by a pulse width modulation signal with a 100% duty cycle to start braking until it stops;

[0008] In the case of the second mode, the motor is controlled by a pulse width modulation signal of a first preset duty cycle to start braking until the motor stops; the first preset duty cycle is less than 100% duty cycle;

[0009] In the case of the third mode, the motor is braked by time-sharing control of a pulse width modulation signal with a 100% duty cycle and a pulse width modulation signal with a second preset duty cycle respectively, until it stops; the second preset duty cycle is less than 100% duty cycle.

[0010] In an optional implementation, the brake mode control switch is mounted on the housing of the electric tool.

[0011] In an alternative embodiment, the braking mode control switch includes at least one of a button and a knob.

[0012] In an alternative embodiment, the knob is further configured to adjust at least one of the magnitude of the second preset duty ratio and the slow braking time during which the motor is controlled by a pulse width modulation signal of the second preset duty ratio to perform braking.

[0013] In an alternative embodiment, the knob includes at least one of a stepped knob and a stepless knob.

[0014] In an alternative embodiment, the power tool includes a switching circuit;

[0015] The switching circuit includes a button configured to switch between a high level and a low level of a first control signal provided to the controller, so that the controller generates and outputs a pulse width modulation signal corresponding to the high level to control the braking mode of the motor to be one of the first mode, the second mode, and the third mode; or generates and outputs a pulse width modulation signal corresponding to the low level to control the braking mode of the motor to be another one of the first mode, the second mode, and the third mode.

[0016] In an alternative embodiment, the button is a switch;

[0017] A first end of the switch is connected to the ground terminal, and a second end of the switch is connected to a first input terminal of the controller.

[0018] In an alternative embodiment, the power tool includes an adjustment circuit;

[0019] The adjustment circuit includes a knob configured to adjust the voltage value of a second control signal provided to the controller, so that the controller generates and outputs a pulse width modulation signal corresponding to the voltage value to control the braking mode of the motor to be one of the first mode, the second mode, and the third mode, and to adjust the magnitude of the second preset duty ratio and / or the slow braking time in the case of the third mode.

[0020] In an alternative embodiment, the knob is a variable resistor;

[0021] The adjustment circuit further includes a second capacitor, a first resistor, and a second resistor;

[0022] An adjustable end of the variable resistor is connected to a first end of the first resistor, a second end of the first resistor is connected to a first end of the second capacitor and is configured to receive a first voltage signal, a second end of the second capacitor and a first end of the variable resistor are respectively connected to the ground terminal, a second end of the variable resistor is connected to a first end of the second resistor, and a second end of the second resistor is connected to a second input terminal of the controller.

[0023] In an alternative embodiment, the power tool further includes a controller and a brake control circuit;

[0024] The brake control circuit includes a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, and a sixth transistor;

[0025] The first transistor and the fourth transistor are sequentially connected in series between a first voltage terminal and a second voltage terminal, the second transistor and the fifth transistor are sequentially connected in series between the first voltage terminal and the second voltage terminal, and the third transistor and the sixth transistor are sequentially connected in series between the first voltage terminal and the second voltage terminal; a first phase connection terminal of the motor is connected between the first transistor and the fourth transistor, a second phase connection terminal of the motor is connected between the second transistor and the fifth transistor, and a third phase connection terminal of the motor is connected between the third transistor and the sixth transistor;

[0026] A control terminal of the first transistor is connected to a first output terminal of the controller, a control terminal of the second transistor is connected to a second output terminal of the controller, a control terminal of the third transistor is connected to a third output terminal of the controller, a control terminal of the fourth transistor is connected to a fourth output terminal of the controller, a control terminal of the fifth transistor is connected to a fifth output terminal of the controller, and a control terminal of the sixth transistor is connected to a sixth output terminal of the controller;

[0027] Control terminals of at least two of the fourth transistor, the fifth transistor, and the sixth transistor are respectively configured to input the pulse width modulation signal.

[0028] The beneficial effects brought by the technical solution provided by the embodiments of the present application include: by adding a brake mode control switch to the power tool, a brake mode selection function is added to the power tool, and the brake mode can be selected according to the user's own preference for the impact sound. The user can flexibly operate the brake mode control switch according to his own needs to arbitrarily switch and / or adjust the brake mode of the power tool motor. The brake modes include at least two of a first mode, a second mode, and a third mode, thereby solving the technical problem that the brake mode of the tool cannot be arbitrarily adjusted, making it more convenient and direct for the user to switch the required brake mode, and improving the user experience.

[0029] Additional aspects and advantages of the embodiments of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings described herein are used to provide a further understanding of the present application and form a part of the present application. Among them, 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. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation of the present application. In the accompanying drawings:

[0031] Figure 1 It is a schematic diagram of the whole machine of the first example of the power tool in the embodiment of the present application;

[0032] Figure 2 It is a schematic diagram of the whole machine of the second example of the power tool in the embodiment of the present application;

[0033] Figure 3 It is a schematic diagram of the circuit of the first example of the power tool in the embodiment of the present application;

[0034] Figure 4 It is a schematic diagram of the circuit of the second example of the power tool in the embodiment of the present application;

[0035] Figure 5 It is a waveform schematic diagram of the first example of the pulse width modulation signal in the embodiment of the present application;

[0036] Figure 6 It is a waveform schematic diagram of the second example of the pulse width modulation signal in the embodiment of the present application;

[0037] Figure 7 It is a waveform schematic diagram of the third example of the pulse width modulation signal in the embodiment of the present application;

[0038] Figure 8 It is a schematic diagram of the structure of a specific example of the metal chuck of the power tool. Detailed implementation manners

[0039] To make the technical solutions and beneficial effects of the embodiments of the present application more obvious and understandable, the following is a clear and complete description by way of listing specific embodiments. Obviously, the listed embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0040] It should be noted that terms such as "first" and "second" may be used in this document to describe various components, but these components are not limited by these terms. These terms are only used to distinguish one component from another. When describing the "first", it does not necessarily mean that the "second" exists; and when discussing the "second", it does not indicate that the "first" necessarily exists in this application. The singular forms of "a", "an", and "the" may also be intended to include the plural forms, unless the context clearly indicates otherwise. The term "comprising" is used to determine the existence of the included features, but does not exclude the existence or addition of one or more other features. The term "and / or" includes any and all combinations of the related listed items. The meaning of the term "plural" is two or more. The term "connected" means that there is a transfer of electrical signals or data between the connected end and the end to which it is connected, and can be understood as "electrically connected", "communicatively connected", etc. "Connected" can be a direct connection between two components, an indirect connection established through other components, a connection within two components, or any other possible connection form.

[0041] An embodiment of the present application provides a power tool, such as an electric drill, an electric wrench, a hammer drill, etc. As Figure 1 and Figure 2 shown, the power tool includes a braking mode control switch 100 configured to switch and / or adjust the braking mode of the power tool motor;

[0042] The braking modes include at least two of a first mode, a second mode, and a third mode;

[0043] In the case of the first mode, the motor is controlled by a pulse width modulation signal with a 100% duty cycle to start braking until it stops;

[0044] In the case of the second mode, the motor is controlled by a pulse width modulation signal with a first preset duty cycle to start braking until it stops; the first preset duty cycle is less than the 100% duty cycle;

[0045] In the case of the third mode, the motor is controlled by time-sharing of a pulse width modulation signal with a 100% duty cycle and a pulse width modulation signal with a second preset duty cycle to brake until it stops; the second preset duty cycle is less than the 100% duty cycle.

[0046] In the embodiments of the present application, the braking mode control switch 100 (such as a one-key switching button) can be used to switch the braking mode of the motor. That is, the braking mode control switch 100 can switch the braking mode of the motor back and forth between two of the first mode (direct braking), the second mode (slow braking), and the third mode (direct braking + slow braking). For example, it can switch back and forth between the first mode (direct braking) and the second mode (slow braking), or it can also switch back and forth between the first mode (direct braking) and the third mode (direct braking + slow braking). Those skilled in the art should understand that it can be configured to switch between any two modes, and no further enumeration is provided here.

[0047] The braking mode control switch 100 (such as a braking adjustment knob) can be used to adjust the braking mode of the motor. That is, the braking mode control switch 100 can adjust the braking mode of the motor back and forth between the first mode (direct braking), the second mode (slow braking), and the third mode (slow braking + direct braking). For example, by rotating the knob in one direction, the braking mode of the motor can be sequentially adjusted from the first mode (direct braking) to the third mode (slow braking + direct braking) to the second mode (slow braking); or conversely, it can also be sequentially adjusted from the second mode (slow braking) to the third mode (slow braking + direct braking) to the first mode (direct braking).

[0048] When directly braking, the motor stops quickly and will emit a relatively large impact sound; when slowly braking, the braking mode is softer and the impact sound is smaller.

[0049] The duty cycle of the pulse width modulation (PWM) signal is the percentage of the time that the pulse is at a high voltage in the entire pulse period. A 100% duty cycle means that the time that the pulse is at a high voltage fills the entire pulse period. In the present application, the high voltage and the low voltage are defined as relative values, not absolute values. The magnitude of the first preset duty cycle can be set as a preset fixed value according to actual needs. For example, it can be a 50% duty cycle. When the one-key switching button switches the braking mode of the motor to the second mode (slow braking), braking can start at a fixed duty cycle of 50% until it stops.

[0050] The magnitude of the second preset duty cycle can be configured as a preset fixed value or adjustable according to actual needs. For example, in the third mode, the magnitude of the second preset duty cycle can increase or decrease as the braking adjustment knob is rotated in one direction.

[0051] In the embodiments of the present application, by adding a brake mode control switch to the power tool, a brake mode selection function is added to the power tool, and the brake mode can be selected according to the user's own preference for the impact sound. The user can flexibly operate the brake mode control switch according to their own needs to arbitrarily switch and / or adjust the brake mode of the power tool motor. The brake modes include at least two of the first mode, the second mode, and the third mode, thereby solving the technical problem that the tool brake mode cannot be arbitrarily adjusted, making it more convenient and direct for the user to switch to the required brake mode, and improving the user experience.

[0052] In an alternative embodiment, as Figure 1 and Figure 2 shown, the brake mode control switch 100 is installed on the housing 200 of the power tool.

[0053] In the embodiments of the present application, a brake mode control switch 100 (such as a toggle button or a knob) can be added to the body of the housing 200 of the power tool, facilitating the user to flexibly switch the brake mode according to their own needs.

[0054] In an alternative embodiment, the brake mode control switch 100 includes at least one of a button and a knob.

[0055] In the embodiments of the present application, the button can be used to switch the brake mode of the power tool motor in one key, and the knob can be used to rotate and adjust the brake mode of the power tool motor to improve the user experience. Some switches can also be rotated and adjusted after being pressed, having the functions of a button and a knob, and can also be used as the brake mode control switch 100.

[0056] When the brake mode is switched to the third mode (slow brake + direct brake) in one key through the button, the magnitude of the second preset duty ratio can be a fixed preset value at this time, and the slow brake time (the motor is controlled by the pulse width modulation signal of the second preset duty ratio to brake) can also be a preset fixed time. For example, the motor is first controlled by the pulse width modulation signal of the second preset duty ratio of this fixed preset value to start braking, and after this preset predetermined time, it is then controlled by the pulse width modulation signal of 100% duty ratio to continue braking until it stops.

[0057] In an alternative embodiment, the knob is further configured to adjust at least one of the magnitude of the second preset duty ratio and the slow brake time for which the motor is controlled by the pulse width modulation signal of the second preset duty ratio to brake.

[0058] In the embodiments of the present application, as the knob rotates in one direction, the magnitude of the second preset duty cycle can be correspondingly increased or decreased; the slow braking time can also be correspondingly increased or decreased. For example, when adjusting the braking mode through the knob, the adjustment process can be as follows: at the initial position of the knob, the braking mode is direct braking; when the knob is rotated in one direction, the slow braking time gradually increases, and the magnitude of the second preset duty cycle can gradually increase, or gradually decrease, or remain unchanged, and the braking mode is slow braking + direct braking; when the knob is rotated to the end, the braking mode is slow braking; the maximum slow braking time can be set according to actual needs, for example, it can be 2s. Of course, the adjustment process can also be reversed, which can be: at the initial position of the knob, the braking mode can also be slow braking (the slow braking time is the maximum time); when the knob is rotated in one direction, the slow braking time gradually decreases, and the magnitude of the second preset duty cycle can gradually increase, or gradually decrease, or remain unchanged, and the braking mode is slow braking + direct braking; when the knob is rotated to the end, the braking mode is direct braking.

[0059] In the embodiments of the present application, by configuring the knob to adjust the magnitude of the second preset duty cycle and / or the slow braking time, users can further flexibly operate the braking mode according to their own needs, further improving the user experience.

[0060] In an alternative embodiment, the knob includes at least one of a stepped knob and a stepless knob.

[0061] In the embodiments of the present application, the adjustment of the stepped knob can be a jump-type adjustment method, and compared with the stepped knob, the adjustment of the stepless knob can be a smooth adjustment method, both of which can increase the flexibility of braking mode adjustment.

[0062] In an alternative embodiment, as Figure 3 shown, the power tool includes a switching circuit 300;

[0063] The switching circuit 300 includes a button configured to switch the high level and the low level of the first control signal provided to the controller 400, so that the controller 400 generates and outputs a pulse width modulation signal corresponding to the high level to control the braking mode of the motor 600 to be one of a first mode, a second mode, and a third mode; or generates and outputs a pulse width modulation signal corresponding to the low level to control the braking mode of the motor 600 to be another one of the first mode, the second mode, and the third mode.

[0064] In this application, the high level and the low level are defined as relative values, not absolute values. The button can be the switch SW. When the switch SW is open, the first control signal is at a high level (high impedance state), and the braking mode of the motor is the first type; when the switch SW is closed, the first control signal is at a low level (such as 0V), and the braking mode of the motor is the second type. For example, the first type can be direct braking, and the second type can be slow braking. Or the first type can be direct braking, and the second type can be slow braking + direct braking. Or the first type can be slow braking, and the second type can be slow braking + direct braking, thus improving the flexibility and convenience of the user's choice of braking modes and enhancing the user experience.

[0065] In an alternative embodiment, the button is the switch SW; the first terminal of the switch SW is connected to the ground terminal, and the second terminal of the switch SW is connected to the first input terminal of the controller 400.

[0066] In the embodiment of this application, a first capacitor C1 can be connected in parallel across both ends of the button (switch) SW to improve stability.

[0067] In an alternative embodiment, as Figure 4 shown, the power tool includes an adjustment circuit 700;

[0068] The adjustment circuit 700 includes a knob configured to adjust the voltage value of the second control signal provided to the controller 400, so that the controller 400 generates and outputs a pulse width modulation signal corresponding to the voltage value to control the braking mode of the motor to be one of the first mode, the second mode, and the third mode, and to adjust the size of the second preset duty cycle and / or the slow braking time in the case of the third mode.

[0069] In the embodiment of this application, the knob can adjust the voltage value of the second control signal between a first voltage value and a second voltage value. For example, when the second control signal is at the first voltage value, the braking mode is the first mode (direct braking); when the second control signal is at the second voltage value, the braking mode is the second mode (slow braking); when the second control signal is at any value between the first voltage value and the second voltage value, the braking mode is the third mode (direct braking + slow braking). And the size of the second preset duty cycle and the slow braking time can also be determined according to this value. The first voltage value can be greater than the second voltage value, or vice versa, which is not limited here, thus improving the flexibility and convenience of the user's choice of braking modes and enhancing the user experience.

[0070] In an alternative embodiment, the knob is a variable resistor VR;

[0071] The adjustment circuit 700 further includes a second capacitor C2, a first resistor R1, and a second resistor R2;

[0072] The adjustable terminal of the adjustable resistor VR is connected to the first terminal of the first resistor R1. The second terminal of the first resistor R1 is connected to the first terminal of the second capacitor C2 and configured to receive the first voltage signal V1. The second terminal of the second capacitor C2 and the first terminal of the adjustable resistor VR are respectively connected to the ground terminal. The second terminal of the adjustable resistor VR is connected to the first terminal of the second resistor R2. The second terminal of the second resistor R2 is connected to the second input terminal of the controller.

[0073] In the embodiment of the present application, the adjustable resistor is used to adjust the voltage value of the second control signal. The adjustable resistor can be a stepless or stepped adjustable resistor. The stability is improved by the second capacitor C2.

[0074] Those skilled in the art should understand that the button SW and the adjustable resistor can be integrated into one device on the switching device.

[0075] In an alternative embodiment, as Figure 3 and Figure 4 shown, the power tool further includes a controller 400 and a brake control circuit 500;

[0076] The brake control circuit 500 includes a first transistor Q1, a second transistor Q2, a third transistor Q3, a fourth transistor Q4, a fifth transistor Q5, and a sixth transistor Q6;

[0077] The first transistor Q1 and the fourth transistor Q4 are sequentially connected in series between the first voltage terminal VDD and the second voltage terminal VSS. The second transistor Q2 and the fifth transistor Q5 are sequentially connected in series between the first voltage terminal VDD and the second voltage terminal VSS. The third transistor Q3 and the sixth transistor Q6 are sequentially connected in series between the first voltage terminal VDD and the second voltage terminal VSS. The first phase connection terminal Uu of the motor 600 is connected between the first transistor Q1 and the fourth transistor Q4. The second phase connection terminal Uv of the motor 600 is connected between the second transistor Q2 and the fifth transistor Q5. The third phase connection terminal Uw of the motor 600 is connected between the third transistor Q3 and the sixth transistor Q6;

[0078] The control terminal of the first transistor Q1 is connected to the first output terminal of the controller 400. The control terminal of the second transistor Q2 is connected to the second output terminal of the controller 400. The control terminal of the third transistor Q3 is connected to the third output terminal of the controller 400. The control terminal of the fourth transistor Q4 is connected to the fourth output terminal of the controller 400. The control terminal of the fifth transistor Q5 is connected to the fifth output terminal of the controller 400. The control terminal of the sixth transistor Q6 is connected to the sixth output terminal of the controller 400;

[0079] The control terminals of at least two of the fourth transistor Q4, the fifth transistor Q5, and the sixth transistor Q6 are respectively configured to input pulse width modulation signals.

[0080] In the embodiments of the present application, the first voltage terminal VDD can provide a high level, and the second voltage terminal VSS can provide a low level (such as 0V). The first output terminal, the second output terminal, and the third output terminal of the controller 400 can respectively output a high level to control the first transistor Q1, the second transistor Q2, and the third transistor Q3 to conduct.

[0081] In the case of the first mode (direct braking), the button (switch) SW can be turned on, the first control signal can be in a high-impedance state, or turning the knob can make the adjustable resistor VR have a first resistance value, and the second control signal is a first voltage value. At this time, the fourth output terminal, the fifth output terminal, and the sixth output terminal of the controller 400 can respectively output a pulse-width modulation signal with a 100% duty cycle (as Figure 5 shown), to control the fourth transistor Q4, the fifth transistor Q5, and the sixth transistor Q6 to conduct directly, so as to achieve braking with a 100% duty cycle until the vehicle stops.

[0082] In the case of the second mode (gentle braking), the button (switch) SW can be closed, the first control signal can be 0V, or turning the knob can make the adjustable resistor VR have a second resistance value (turned to the end), and the second control signal is a second voltage value. At this time, at least two of the fourth output terminal, the fifth output terminal, and the sixth output terminal of the controller 400 can respectively output a pulse-width modulation signal with a first preset duty cycle (or a second preset duty cycle, such as a 50% duty cycle) (as Figure 6 shown), to control at least two of the fourth transistor Q4, the fifth transistor Q5, and the sixth transistor Q6 to conduct and cut off intermittently, so as to achieve braking with a fixed duty cycle until the vehicle stops. The maximum gentle braking time can be 2s.

[0083] In the case of the third mode (direct braking + gentle braking), turning the knob can make the adjustable resistor VR have a third resistance value between the first resistance value and the second resistance value, and the second control signal is a third voltage value. At this time, the gentle braking time can be adjusted to a period of time corresponding to the third voltage value (such as 300ms), and the second preset duty cycle can be adjusted to a set value corresponding to the third voltage value. At least two of the fourth output terminal, the fifth output terminal, and the sixth output terminal of the controller 400 can first respectively output a pulse-width modulation signal with the set value duty cycle for a period of time (such as 300ms), and then respectively output a pulse-width modulation signal with a 100% duty cycle (as Figure 7 shown), to control at least two of the fourth transistor Q4, the fifth transistor Q5, and the sixth transistor Q6 to conduct and cut off intermittently for this period of time (such as 300ms), and then all conduct directly until the vehicle stops.

[0084] Those skilled in the art should understand that the specific control methods in the above three cases are only specific examples and are not limited thereto. Other control methods for switching or adjusting the above three braking methods can be set according to actual needs and will not be enumerated here.

[0085] In the embodiments of the present application, by adding a brake mode switching button or knob to the fuselage, users can flexibly switch according to their own needs. For example, one is button-type switching. By detecting the high and low levels at the button (switch), the switching between direct braking and slow braking can be achieved; the other is knob-type switching. When the knob is in the initial position, the tool braking mode can be direct braking. When the knob is rotated, the braking mode of the tool can change from direct braking to slow braking + direct braking. As the knob is turned, the time of slow braking gradually increases, up to 2 s at most. Among them, the knob can be a stepped knob or a stepless knob.

[0086] In the present application, the transistor may include at least one of devices such as BJT (bipolar junction transistor), SCR (silicon controlled rectifier), GTO (gate turn-off thyristor), MOSFET (metal oxide semiconductor field effect transistor, simply referred to as MOS transistor), IGBT (insulated gate bipolar transistor), MCT (MOS controlled thyristor), and SIT (static induction transistor).

[0087] The controller 400 may be a processing unit with data processing capabilities and / or instruction execution capabilities. For example, it may be a microcontroller unit (MCU), etc. The controller 400 may be connected to a memory. The memory may include one or more computer program products. The computer program products 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, etc. 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 controller 400 may run the computer program instructions to implement the above functions configured by the controller 400 and / or other desired functions.

[0088] It should be understood that the above embodiments are all exemplary and do not cover all possible implementation manners included in the claims. Without departing from the scope of the present disclosure, various deformations and changes can be made based on the above embodiments. Similarly, the various technical features of the above embodiments can be arbitrarily combined to form additional embodiments of the present application that may not be clearly described. Therefore, the above embodiments only represent several implementation manners of the present application and do not limit the protection scope of the patent of the present application.

Claims

1. An electric tool, characterized in that: The power tool comprises a brake mode control switch configured to switch and / or adjust the brake mode of the power tool motor; The brake mode control switch includes at least one of a button and a knob; The electric tool further comprises a switching circuit and / or a regulating circuit; The switching circuit includes a button, and the switching circuit is electrically connected to the controller of the electric tool and is used to switch the braking mode; The regulating circuit includes a knob, the regulating circuit is electrically connected to the controller, and is used to switch or adjust the braking mode; The electric tool further comprises a brake control circuit, which is electrically connected to the controller and is used to control the electric tool to brake; The braking method includes at least two of a first method, a second method and a third method; In the case of the first mode, the motor is controlled by a pulse width modulation signal with a 100% duty cycle to start braking until it stops; In the case of the second mode, the motor is controlled by a pulse width modulation signal of a first preset duty cycle to start braking until the motor stops; the first preset duty cycle is less than 100% duty cycle; In the case of the third mode, the motor is braked by time-sharing control of a pulse width modulation signal with a 100% duty cycle and a pulse width modulation signal with a second preset duty cycle respectively, until it stops; the second preset duty cycle is less than 100% duty cycle.

2. The electric tool according to claim 1, characterized in that: The brake mode control switch is mounted on the housing of the electric tool.

3. The electric tool according to claim 1, characterized in that: The knob is also configured to adjust at least one of the size of the second preset duty cycle and the de-braking time of the motor being controlled by a pulse width modulation signal of the second preset duty cycle to brake.

4. The electric tool according to claim 3, characterized in that: The knob includes at least one of a stepped knob and a stepless knob.

5. The electric tool according to claim 1, characterized in that: The button is configured to switch the high level and the low level of the first control signal provided to the controller, so that the controller generates and outputs a pulse width modulation signal corresponding to the high level to control the braking mode of the motor to be one of the first mode, the second mode and the third mode; or generates and outputs a pulse width modulation signal corresponding to the low level to control the braking mode of the motor to be another of the first mode, the second mode and the third mode.

6. The electric tool according to claim 5, characterized in that: The button is a switch; The first end of the switch is connected to the ground, and the second end of the switch is connected to the first input end of the controller.

7. The electric tool according to claim 4, characterized in that: The knob is configured to adjust the voltage value of the second control signal provided to the controller so that the controller generates and outputs a pulse width modulation signal corresponding to the voltage value to control the braking mode of the motor to be one of the first mode, the second mode and the third mode, and to adjust the size of the second preset duty cycle and / or the braking time under the third mode.

8. The electric tool according to claim 7, characterized in that: The knob is an adjustable resistor; The regulating circuit also includes a second capacitor, a first resistor and a second resistor; The adjustable end of the adjustable resistor is connected to the first end of the first resistor, the second end of the first resistor is connected to the first end of the second capacitor and is configured to receive a first voltage signal, the second end of the second capacitor and the first end of the adjustable resistor are respectively connected to the ground, the second end of the adjustable resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the second input end of the controller.

9. The electric tool according to claim 1, characterized in that: The brake control circuit includes a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor and a sixth transistor; The first transistor and the fourth transistor are connected in series between the first voltage terminal and the second voltage terminal, the second transistor and the fifth transistor are connected in series between the first voltage terminal and the second voltage terminal, and the third transistor and the sixth transistor are connected in series between the first voltage terminal and the second voltage terminal; the first phase connection end of the motor is connected between the first transistor and the fourth transistor, the second phase connection end of the motor is connected between the second transistor and the fifth transistor, and the third phase connection end of the motor is connected between the third transistor and the sixth transistor; The control end of the first transistor is connected to the first output end of the controller, the control end of the second transistor is connected to the second output end of the controller, the control end of the third transistor is connected to the third output end of the controller, the control end of the fourth transistor is connected to the fourth output end of the controller, the control end of the fifth transistor is connected to the fifth output end of the controller, and the control end of the sixth transistor is connected to the sixth output end of the controller; Control terminals of at least two of the fourth transistor, the fifth transistor and the sixth transistor are respectively configured to input the pulse width modulation signal.

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