Electric tool and control method thereof

Abstract

The invention discloses an electric tool and a control method thereof. The electric tool includes: a motor; the power supply device comprises a power supply and is arranged to at least supply power to the motor; the driving device is arranged to drive the motor to operate; the operation device is set to be operated by a user to switch the on-off state of the electric tool and output a corresponding on signal or off signal; the first controller is set to output a driving signal to the driving device when receiving the opening signal; the second controller is set to output a driving enable signal to the driving device when the starting signal is received; and the driving device is further arranged to drive the motor to operate when receiving the driving signal and the driving enable signal. Double guarantees are achieved through the double controllers, and the tool safety is improved.

Description

Technical Field

[0001] The present application relates to an electric tool and a control method thereof. Background Art

[0002] The free end of the output shaft of the power tool is generally equipped with functional parts such as drill bits and saw blades, and is provided with operating parts that can be operated by the user to switch the switch state of the tool. When the user operates the power tool to switch from the off state to the on state, the motor in the tool will be driven to operate so that the functional parts can perform operations such as tightening and cutting. When the user operates the power tool to switch from the on state to the off state, the motor in the tool will be controlled to stop, and the functional parts will also not operate. In order to ensure the safety of the user, the power tool must not cause problems such as accidental startup or inability to shut down during the above process. In addition, in some scenarios, after the motor in the tool stops, the user may still need to use the lighting, display and other functions of the power tool.

[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 motor; a power supply device, comprising a power supply and configured to supply power to at least the motor; a driving device, configured to drive the motor to operate; an operating device, configured to be operated by a user to switch the on / off state of the electric tool and output a corresponding on signal or off signal; wherein the electric tool further comprises: a first controller, connected to the operating device and the driving device, and configured to output a driving signal to the driving device upon receiving a turning-on signal; a second controller, connected to the operating device and the driving device, and configured to output a driving enable signal to the driving device upon receiving a turning-on signal; and the driving device is further configured to drive the motor to operate upon receiving a driving signal and a driving enable signal.

[0007] In some embodiments, the first controller is further configured to stop outputting the driving signal to the driving device upon receiving a shutdown signal.

[0008] In some embodiments, the power supply device is connected to the first controller, and the power supply device is further configured to output a first enable signal to the first controller when receiving a start signal.

[0009] In some embodiments, the first controller is also configured to output a first power-off signal to the power supply device after waiting for a first preset period of time when receiving a shutdown signal; the power supply device is also configured to stop outputting a first enable signal to the first controller when receiving the first power-off signal.

[0010] In some embodiments, the first controller is further configured to output a maintenance signal to the power supply device when receiving a start signal; the power supply device is further configured to continue to output the first enable signal to the first controller when losing the start signal but receiving the maintenance signal.

[0011] In some embodiments, the first controller is also configured to stop outputting a maintenance signal to the power supply device after waiting for a first preset period of time when receiving a shutdown signal; the power supply device is also configured to stop outputting a first enable signal to the first controller when the maintenance signal is lost.

[0012] In some embodiments, the electric tool also includes: a parameter detection device, connected to the motor and the second controller, and configured to detect the operating parameters of the motor and transmit the operating parameters of the motor to the second controller; the second controller is also configured to output a second power-off signal to the power supply device after receiving a shutdown signal and after a second preset time period, when the operating parameters are still in a changing state; the power supply device is also configured to stop outputting the first enable signal to the first controller when receiving the second power-off signal.

[0013] In some embodiments, the second controller is further configured to stop outputting a drive enable signal to the drive device after receiving the shutdown signal and a second preset time period has elapsed.

[0014] In some embodiments, the first controller is further configured to stop outputting the driving signal to the driving device when the first enabling signal is lost.

[0015] A control method for an electric tool comprises: when the electric tool is switched to an on state, an operating device outputs an on signal to a first controller and a second controller; when the first controller receives the on signal, the first controller outputs a drive signal to a drive device; when the second controller receives the on signal, the second controller outputs a drive enable signal to the drive device; when the drive device receives the drive signal and the drive enable signal, the drive motor operates.

[0016] The benefit of the present application lies in that driving the normal operation of the motor in the electric tool requires both a control drive signal provided by the first controller and an enabling drive enable signal provided by the second controller. If either of the two controllers fails, the motor cannot be driven to operate, thereby providing double protection to avoid problems such as accidental startup, thereby improving the safety of the tool and the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a perspective view of an electric tool shown in an embodiment;

[0018] Figure 2 yes Figure 1 The electric control schematic diagram of the electric tool shown;

[0019] Figure 3 yes Figure 2 A circuit block diagram of a motor, a driving device, a first controller, and a second controller in the electric tool shown;

[0020] Figure 4 yes Figure 2 A partial circuit diagram of a drive device in the electric tool shown;

[0021] Figure 5 yes Figure 1 Another electrical control schematic diagram of the electric tool shown;

[0022] Figure 6 yes Figure 5 Partial circuit diagram of the power supply device and operating device in the electric tool shown;

[0023] Figure 7 yes Figure 1 Another electric control schematic diagram of the electric tool shown;

[0024] Figure 8 yes Figure 7 Partial circuit diagram of the power supply device and operating device in the electric tool shown;

[0025] Fig. 9 The figure is a flow chart of a method for controlling an electric tool according to an embodiment. DETAILED DESCRIPTION

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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).

[0031] 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.

[0032] 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.

[0033] 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.

[0034] In the present application, the terms “device”, “module” or “unit” may be implemented in the form of hardware or software to achieve specific functions.

[0035] 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.).

[0036] The technical solution of the present application is described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Figure 1 An electric tool 100 is shown as one embodiment in the present application. Figure 1 The electric tool 100 shown is a DC electric drill. The electric tools in other embodiments may also be other types of hand-held tools such as nail guns and electric circular saws, or bench-type tools such as miter saws and table saws.

[0038] refer to Figure 2 , Figure 2 for Figure 1The electric control schematic diagram of the electric tool 100 is shown. The electric tool 100 includes: a motor 110, a power supply device 120 and a drive device 130. Among them, the motor shaft of the motor 110 can drive the output shaft to rotate directly or indirectly through a transmission component after rotation, so that the output shaft drives the assembly parts such as a drill bit and a saw blade connected thereto to perform operations such as fastening and cutting. In some examples, the motor 110 can be a DC brushless motor. The power supply device 120 includes a power supply and can at least power the motor 110. In some examples, the power supply device 120 can include a power supply such as a detachable battery pack, and integrated power chips, transistors and components such as resistors, capacitors, and inductors. The drive device 130 is connected to the motor 110 and can drive the motor 110 to operate for fastening, cutting, and other operations. In some examples, the drive device 130 can include a three-phase inverter bridge, a drive chip, and the like.

[0039] The electric tool 100 also includes an operating device 140 for the user to operate to switch the switch state of the electric tool 100. In some examples, the operating device 140 may include a mechanical switch, a signal switch, etc. The operating device 140 is connected to the power supply device 120, and is connected to the first controller 150 and the second controller 160 to be described later. When the user activates the electric tool 100, the operating device 140 may output an on signal to the first controller 150 and the second controller 160, which indicates that the electric tool is activated. When the user stops using the electric tool 100, the operating device 140 may output an off signal to the first controller 150 and the second controller 160, which indicates that the electric tool is deactivated. In some examples, the on signal and the off signal may be voltage signals or voltage jump signals, for example, a high voltage signal is an on signal, and a low voltage signal is an off signal. In other examples, the on signal and the off signal may also be digital signals with more complex formats that carry specific information.

[0040] The power tool 100 also includes a first controller 150 and a second controller 160. In some examples, the first controller 150 may include a processor such as a CPU (Central Processing Unit), an MCU (Microcontroller Unit), and a memory storing processor executable instructions, and the same is true for the second controller 160.

[0041] The first controller 150 is connected to the driving device 130 and the operating device 140, and can receive a start signal from the operating device 140. The first controller 150 can be configured to output a drive signal to the driving device 130 when receiving the start signal. Specifically, the drive signal is a control signal of the driving device 130, which is used to control the driving device 130 to work normally.

[0042] The second controller 160 is connected to the driving device 130 and the operating device 140, and can receive a start signal from the operating device 140. The second controller 160 can be configured to output a drive enable signal to the driving device 130 when receiving the start signal. Specifically, the drive enable signal is a power supply signal or an activation signal of the driving device 130, which is used to provide power to the driving device 130 or activate and turn on components in the driving device 130.

[0043] The driving device 130 is connected to the motor 110, the first controller 150 and the second controller 160, and can receive the driving signal from the first controller 150 and the driving enable signal from the second controller 160. The driving device 130 can be configured to drive the motor 110 to operate when the driving signal and the driving enable signal are received; and cannot drive the motor 110 to operate when only the driving signal is received but the driving enable signal is not received, or when only the driving enable signal is received but the driving signal is not received.

[0044] The following is for Figure 2 Each device in the illustrated power tool 100 is described in more detail.

[0045] refer to Figure 3 In some embodiments, the drive device 130 may be a drive circuit composed of multiple semiconductor switching elements. When the motor 110 is a three-phase motor, the drive circuit may be composed of six semiconductor switching elements. The drive signal output by the first controller 150 will be transmitted to each semiconductor switching element in the drive device 130 to change the on-off state of each semiconductor switching element, and then change the voltage state or current state applied to each winding of the motor 110, so as to control the motor 110 to change phase. The drive enable signal output by the second controller 160 will also be transmitted to the drive device 130 to supply power or turn on the components therein, so that the motor control based on the above drive signal has an energy basis or can be successfully activated. Figure 3 , Figure 4 As shown, the motor 110 is a three-phase motor, and the U-phase drive circuit of the drive device 130 may include a plurality of transistors Q11, Q12, a plurality of resistors and rectifier diodes, etc. In some examples, the transistors Q11 and Q12 in the drive circuit may also be replaced by other semiconductor components such as optocouplers. Among them, the input signal of the transistor Q11 is the drive enable signal PWM_EN, and the input signal of the transistor Q12 is the drive signal ULO. After the drive enable signal PWM_EN is connected, Q11 and Q12 are turned on, and the output signal ULO' of the transistor Q12 can be output to the semiconductor switch element.

[0046] In some embodiments, the operating device 140 may be a toggle switch, which can output an on signal when it is toggled to a position corresponding to the on state, and can output a off signal when it is toggled to a position corresponding to the off state. In other embodiments, the operating device 140 may be a touch switch, and when the electric tool 100 is switched from the off state to the on state, the touch switch is pressed, and the switch contacts briefly contact and then separate. In this case, the jump signal generated is the on signal. For example, the on signal can be a jump signal from high voltage to low voltage. When the electric tool 100 is switched from the on state to the off state, the touch switch is pressed again, and the switch contacts briefly contact and then separate. In this case, the jump signal generated is the off signal. In other time periods, the touch switch is not pressed, the switch contacts are not in contact, and a stable non-jump signal can be continuously output to the outside. For example, a high voltage signal can be continuously output.

[0047] Figures 2 to 4 In the described electric tool 100, the normal operation of the driving motor requires both a control driving signal provided by the first controller and an enabling driving signal provided by the second controller. Both controllers respond to the start signal to output a signal. No matter which of the two controllers fails, the motor cannot be driven to operate, thereby providing double protection for the normal operation of the motor, preventing the problem of accidental startup, and improving the safety of the tool and the user experience.

[0048] In some embodiments, the first controller 150 may also be configured to stop outputting the drive signal to the drive device 130 upon receiving a shutdown signal from the operating device 140. The drive device 130 will not be able to drive the motor 110 to operate after losing the drive signal, and the motor 110 will therefore stop. In other embodiments, in addition to the first controller 150 stopping outputting the drive signal to the drive device 130, the second controller 160 may also be configured to stop outputting the drive enable signal to the drive device 130 upon receiving a shutdown signal from the operating device 140. The drive device 130 will not be able to drive the motor 110 to operate after losing the drive signal and the drive enable signal, and the motor 110 will therefore stop. In this embodiment, both of the dual controllers stop outputting signals in response to the shutdown signal, and in the case where no failure occurs in the dual controllers, the motor can be ensured to stop smoothly.

[0049] refer to Figure 5 , Figure 5The electric control schematic diagram of the electric tool 200 as another embodiment of the present application. The electric tool 200 includes a motor 210, a power supply device 220, a drive device 230, an operating device 240, a first controller 250 and a second controller 260. The electric tool 200 can partially or completely refer to the components and settings of the motor 110, the power supply device 120, the drive device 130, the operating device 140, the first controller 150 and the second controller 160 in the electric tool 100 according to the needs. On the basis of the electric tool 100, the difference between the electric tool 200 and the electric tool 100 is at least that the electric energy of the first controller 250 in the electric tool 200 is provided by the power supply device 220, the power supply process of the power supply device 220 is controlled by the first controller 250, and the electric tool 200 can realize the delayed shutdown function.

[0050] In the electric tool 200, the power supply device 220 is connected to the operating device 240 and the first controller 250. The power supply device 220 can receive the start signal from the operating device 240, and can be configured to output a first enable signal to the first controller 250 when receiving the start signal from the operating device 240, so that the first controller 250 is powered. The first enable signal is a power supply signal of the first controller 250, and can be a voltage signal that meets its voltage requirements. In some embodiments, the power supply device 220 is also connected to the second controller 260, and when receiving the start signal, in addition to outputting the first enable signal to the first controller 250, it can also be configured to output a second enable signal to the second controller 260, so that the second controller 260 is powered. The second enable signal is a power supply signal of the second controller 260, and can be a voltage signal that meets its voltage requirements. The voltage values ​​of the first enable signal and the second enable signal can be the same or different. For example, the first enable signal can be a 12V voltage signal, and the second enable signal can be a 3.3V signal. It is understandable that in other embodiments, the power supply logics of the first controller 250 and the second controller 260 may also be independent of each other.

[0051] The first controller 250 may also be configured to output a first power-off signal to the power supply device 220 after waiting for a first preset time T1 upon receiving a shutdown signal from the operating device 240, and the first power-off signal may be a voltage signal. In some embodiments, the first controller 250 may also be configured to output a first power-off signal to the power supply device 220 upon receiving a shutdown signal from the operating device 240, that is, the first preset time is zero. The power supply device 220 may be configured to stop outputting a first enable signal to the first controller 250 upon receiving the first power-off signal. In some embodiments, upon receiving the first power-off signal, in addition to stopping outputting the first enable signal to the first controller 250, the power supply device 220 may also be configured to stop outputting a second enable signal to the second controller 260. It is understandable that in other embodiments, the power-off logics of the first controller 250 and the second controller 260 may also be independent of each other.

[0052] The following is for Figure 5 Each device in the illustrated power tool 200 is described in more detail.

[0053] In some embodiments, the operating device 240 is a touch switch, and the switch contacts separate after a short contact, and cannot form a continuous circuit loop. Therefore, the power supply device 220 cannot obtain a continuous start signal, and may lose power after power-on as the start signal is lost, and can only supply power to the outside for a short time. In order to enable the power supply device 220 to continue to supply power to the outside after power-on, the first controller 250 can also be configured to output a maintenance signal to the power supply device 220 when receiving the start signal from the operating device 240, so that the power supply device 220 can continue to supply power to the outside when the start signal is lost. The maintenance signal can be a voltage signal. The power supply device 220 can be configured to continue to output the first enable signal to the first controller 250 when the start signal from the operating device 240 is lost, but the maintenance signal from the first controller 250 is received. In some embodiments, it also continues to output the second enable signal to the second controller 260.

[0054] The first controller 250 may also be configured to stop outputting a maintenance signal to the power supply device 220 when receiving a shutdown signal from the operating device 240, so that the power supply device 220 no longer supplies power. The power supply device 20 may be configured to stop outputting the first enable signal to the first controller 250 when losing the start signal and the maintenance signal, and in some embodiments, also stop outputting the second enable signal to the second controller 260. At this time, the first controller 250 no longer outputting the maintenance signal to the power supply device 220 can be regarded as outputting the first power-off signal to the power supply device 220.

[0055] refer to Figure 6, the operating device 240 is a touch switch, and part of the power supply circuit in the power supply device 220 may include multiple transistors Q21, Q22, Q23, multiple resistors, capacitors and voltage-stabilizing diodes. In some examples, the transistors Q21, Q22, Q23 in the power supply circuit may also be replaced by other semiconductor components such as optocouplers. Among them, the input signal of transistor Q23 can be connected to the maintenance signal Powerkeep from the first controller 250. When the switch contacts in the operating device 240 are in contact, the transistor Q21 is short-circuited, the transistor Q22 is turned on, the power supply device 220 is powered on successfully, and Q22 generates an output signal, which can be used as a first enable signal after voltage conversion and other processing. In some embodiments, it can also be used as a second enable signal. After the switch contacts in the operating device 240 are separated, Q21 is no longer turned on and Q22 is also not turned on. In order to enable the power supply device 220 to maintain the power supply state, the first controller 250 receives the start signal and outputs the maintenance signal Powerkeep. The maintenance signal Powerkeep will turn on Q23, and the output signal of Q23 can make Q21 and Q22 continue to be turned on, and Q22 can continue to output signals. Therefore, the first enable signal can continue to be output to the first controller 250. In some embodiments, the second enable signal also continues to be output to the second controller 260.

[0056] When the first controller 250 does not fail, after receiving the shutdown signal and waiting for the first preset time T1, the first controller 250 no longer outputs the maintenance signal Powerkeep, Q23 is no longer turned on, Q21 and Q22 are no longer turned on, Q22 no longer outputs a signal, and the first enable signal output to the first controller 250 is interrupted. In some embodiments, the second enable signal output to the second controller 260 is also interrupted.

[0057] Figure 5 to Figure 6 In the described electric tool 200, the electric energy sources of the first controller and the second controller are the enable signals output by the power supply device. When the first controller receives the shutdown signal, it will try to interrupt the power supply of the power supply device after waiting for a preset time. If there is no failure in the first controller, the delayed shutdown function of the electric tool can be safely realized. In the standby state where the motor stops but the whole machine is not powered off, the dual controllers can quickly respond to user operations or control auxiliary functions such as lighting and display until it is finally shut down.

[0058] refer to Figure 7 , Figure 7The electric control schematic diagram of the electric tool 300 as another embodiment of the present application. The electric tool 300 includes a motor 310, a power supply device 320, a drive device 330, an operating device 340, a first controller 350 and a second controller 360, and also includes a parameter detection device 370. The electric tool 300 can partially or completely refer to the component composition and setting method of the motor 210, the power supply device 220, the drive device 230, the operating device 240, the first controller 250 and the second controller 260 in the electric tool 200 according to the needs. On the basis of the electric tool 200, the difference between the electric tool 300 and the electric tool 200 is at least that the power supply process of the power supply device 320 in the electric tool 300 is controlled by the second controller 360 in addition to the first controller 350, and can be safely shut down in the event of a failure of the first controller 350.

[0059] In the electric tool 300, the parameter detection device 370 is connected to the motor 310 and the second controller 360. The parameter detection device 370 can detect motor operating parameters such as phase current, phase voltage, rotor position, motor speed, etc., and can be configured to detect the operating parameters of the motor 310 and transmit the operating parameters to the second controller 360. In some examples, the parameter detection device 370 can be various sensors.

[0060] The second controller 360 is also connected to the power supply device 320. The second controller 360 is also configured to wait for a second preset time T2 after receiving a shutdown signal from the operating device 340 to determine whether the operating parameters from the parameter detection device 370 are still in a changing state. The second preset time T2 may be less than or equal to the first preset time T1. After the shutdown signal is sent and the second preset time T2 has passed, if the first controller 350 is not faulty, it has stopped outputting a drive signal to the drive device 330, and the drive device 330 has stopped driving the motor 310 to operate. The operating parameters of the motor 310 should be in an unchanged state. Therefore, if the second controller 360 determines that the motor operating parameters from the parameter detection device 370 are not in a changing state, it may not take action and wait for the first preset time T1 to expire before shutting down naturally.

[0061] When the motor operating parameters are in a changing state, the first controller 350 may have software failures and other problems. The first controller 350 still outputs a driving signal to the driving device 330, and the driving device 330 still drives the motor 310 to operate. In this case, the second controller 360 can be configured to output a second power-off signal to the power supply device 320, and the second power-off signal can be a voltage signal. The power supply device 320 can be configured to stop outputting the first enable signal to the first controller 350 when receiving the second power-off signal from the second controller 360. The first controller 350 will stop outputting the driving signal to the driving device 330 when losing the first enable signal from the power supply device 320, and the driving device 330 will not be able to drive the motor 310 to operate after losing the driving signal, and the motor 310 will stop rotating. In some embodiments, when receiving the second power-off signal, in addition to stopping outputting the first enable signal to the first controller 350, the power supply device 320 can also be configured to stop outputting the second enable signal to the second controller 360 to power off the entire machine.

[0062] In addition, considering that the transistor in the driving device 330 may be damaged when it receives a driving signal from the first controller 350 but does not receive a driving enable signal from the second controller 360, in some embodiments, the second controller 360 may not stop outputting the driving enable signal when receiving a shutdown signal, but may be configured to stop outputting the driving enable signal to the driving device 330 after receiving the shutdown signal and experiencing a second preset time length T2, thereby avoiding the above-mentioned problem of transistor damage.

[0063] Below Figure 7 Each device in the electric tool 300 shown is described in more detail.

[0064] refer to Figure 8 In some embodiments, the operating device 340 is a touch switch, and part of the power supply circuit in the power supply device 320 may include multiple transistors Q31, Q32, Q33, multiple resistors, capacitors and voltage-stabilizing diodes. In some examples, the transistors Q31, Q32, Q33 in the drive circuit may also be replaced by other semiconductor components such as optocouplers. Among them, the input signal of the transistor Q31 can be connected to the second power-off signal Poweroff from the second controller 360, and the input signal of the transistor Q33 can be connected to the maintenance signal Powerkeep from the first controller 350. When the power tool 300 is in the on state, the maintenance signal Powekeep output by the first controller 350 turns on Q33, and Q31 and Q32 are also turned on. The signal output by Q32 is used as the first enable signal after voltage conversion and other processing.

[0065] In the case of a failure of the first controller 350, the first controller 350 cannot stop outputting the driving signal when receiving the shutdown signal, and the driving device 330 still drives the motor 310 to operate, and the parameter detection device 370 transmits the motor operating parameters of the changed state to the second controller 360. After receiving the second preset duration T2 of the shutdown signal, the second controller 360 determines that the current motor operating parameters are in a changed state, and outputs the second power-off signal Poweroff. The second power-off signal Poweroff will disconnect Q21, and Q22 will also be disconnected. Q22 no longer outputs a signal, and the first enable signal output to the first controller 350 is interrupted. The first controller 350 cannot output a driving signal to the driving device 330 due to the loss of power supply. The driving device 330 stops driving the motor 310 due to the loss of the driving signal, and the motor 310 stops rotating. In some embodiments, Q22 no longer outputs a signal, and the second enable signal output to the second controller 360 is also interrupted, and the entire machine loses power.

[0066] Figures 7 and 8 In the described electric tool 300, the second controller confirms whether the motor is still running through the status of the motor operating parameters, that is, confirms whether the first controller is faulty, and tries to interrupt the power supply of the power supply device to the first controller when the parameters change (first controller failure), so that the first controller loses power and stops the output of the driving signal. In this way, when the first controller fails, the motor can be stopped smoothly or further shut down. As long as one of the dual controllers can still work normally, the problem of being unable to shut down will not occur, thereby improving the safety of the tool and the user experience.

[0067] Fig. 9 A flow chart of a method for controlling an electric tool as an embodiment of the present application is shown. Fig. 9 The control method shown can be applied to the electric tool described above.

[0068] The control method of the electric tool may include the following specific steps:

[0069] S902, when the electric tool is switched to the on state, the operating device outputs an on signal to the first controller and the second controller;

[0070] S904, when receiving the start signal, the first controller outputs a driving signal to the driving device;

[0071] S906, when receiving the start signal, the second controller outputs a drive enable signal to the drive device;

[0072] S908, when the driving device receives the driving signal and the driving enable signal, the driving motor operates.

[0073] In some embodiments, upon receiving the shutdown signal, the first controller stops outputting the driving signal to the driving device.

[0074] In some embodiments, the power supply device outputs a first enable signal to the first controller when receiving the start signal.

[0075] In some embodiments, when the first controller receives the shutdown signal, it waits for a first preset period of time and then outputs a first power-off signal to the power supply device; when the power supply device receives the first power-off signal, it stops outputting the first enable signal to the first controller.

[0076] In some embodiments, the first controller outputs a maintenance signal to the power supply device when receiving the start signal; the power supply device continues to output the first enable signal to the first controller when losing the start signal but receiving the maintenance signal.

[0077] In some embodiments, when the first controller receives the shutdown signal, it stops outputting the maintenance signal to the power supply device after waiting for a first preset period of time; when the power supply device loses the maintenance signal, it stops outputting the first enable signal to the first controller.

[0078] In some embodiments, the parameter detection device detects the operating parameters of the motor and transmits the operating parameters of the motor to the second controller; after receiving the shutdown signal and experiencing a second preset time, the second controller outputs a second power-off signal to the power supply device while the operating parameters are still in a changing state; when the power supply device receives the second power-off signal, it stops outputting the first enable signal to the first controller.

[0079] In some embodiments, after receiving the shutdown signal and a second preset time period has elapsed, the second controller stops outputting the drive enable signal to the drive device.

[0080] In some embodiments, the first controller stops outputting the driving signal to the driving device when the first enabling signal is lost.

[0081] 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: Motor; a power supply device, comprising a power source and configured to supply power to at least the motor; A driving device, configured to drive the motor to operate; An operating device, configured to be operated by a user to switch the on / off state of the electric tool and output a corresponding on signal or off signal; Wherein, the electric tool further comprises: A first controller connected to the operating device and the driving device, and configured to output a driving signal to the driving device when receiving the start signal; A second controller is connected to the operating device and the driving device, and is configured to output a driving enable signal to the driving device when receiving the start signal; The driving device is further configured to drive the motor to operate when receiving the driving signal and the driving enable signal.

2. The electric tool according to claim 1, wherein: The first controller is further configured to stop outputting the driving signal to the driving device upon receiving the shutdown signal.

3. The electric tool according to claim 1, wherein: The power supply device is connected to the first controller, and is further configured to output a first enable signal to the first controller when receiving the start signal.

4. The electric tool according to claim 3, wherein: The first controller is also configured to output a first power-off signal to the power supply device after waiting for a first preset period of time when receiving the shutdown signal; the power supply device is also configured to stop outputting the first enable signal to the first controller when receiving the first power-off signal.

5. The electric tool according to claim 3, wherein: The first controller is further configured to output a maintenance signal to the power supply device when receiving the start signal; the power supply device is further configured to continue to output the first enable signal to the first controller when losing the start signal but receiving the maintenance signal.

6. The electric tool according to claim 5, wherein: The first controller is also configured to stop outputting the maintenance signal to the power supply device after waiting for a first preset period of time when receiving the shutdown signal; the power supply device is also configured to stop outputting the first enable signal to the first controller when losing the maintenance signal.

7. The electric tool according to claim 4 or 6, wherein: The electric tool also includes: a parameter detection device, which is connected to the motor and the second controller and is configured to detect the operating parameters of the motor and transmit the operating parameters of the motor to the second controller; the second controller is also configured to output a second power-off signal to the power supply device after receiving the shutdown signal and a second preset time period, while the operating parameters are still in a changing state; the power supply device is also configured to stop outputting the first enable signal to the first controller when receiving the second power-off signal.

8. The electric tool according to claim 7, wherein: The second controller is also configured to stop outputting the drive enable signal to the drive device after receiving the shutdown signal and a second preset time period has elapsed.

9. The electric tool according to claim 7, wherein: The first controller is also configured to stop outputting the driving signal to the driving device when the first enabling signal is lost.

10. A method for controlling an electric tool, comprising: When the electric tool is switched to the on state, the operating device outputs an on signal to the first controller and the second controller; When the first controller receives the start signal, it outputs a drive signal to the drive device; The second controller outputs a driving enable signal to the driving device when receiving the start signal; When the driving device receives the driving signal and the driving enable signal, the driving device drives the motor to operate.

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