Power tool

Abstract

The utility model discloses an electric tool, including power supply circuit, switch subassembly, detection circuit, control circuit, state holding circuit and motor, and the torque that motor can output is at least 1500Nm, the switch subassembly is triggered and controls the power output of power supply circuit connection, and the state change of switch subassembly is detected to detection circuit, and the trigger signal is output to control circuit when switch subassembly is triggered, and control circuit exports first control signal to state holding circuit, and first control signal configuration is control electric tool is in working condition or standby state, and the level of response first control signal of state holding circuit is first level, and the connection of power supply circuit and motor is disconnected to make electric tool is in standby state, and the level of response first control signal is second level, and the connection of power supply circuit and motor is switched on to make electric tool is in working condition, and control circuit is in working condition and response received trigger signal, and control motor runs.

Description

Technical Field

[0001] This utility model relates to the field of motor control technology, and in particular to an electric tool. Background Technology

[0002] In the field of power tools, especially handheld power tools such as electric wrenches, the motor is usually started by directly pressing a trigger switch. This control method is simple and convenient for low-torque power tools, but it poses a significant safety hazard for high-torque electric wrenches. When a user accidentally touches the trigger switch, the motor starts immediately and outputs high torque, which can easily lead to injury to the operator or damage to the equipment. Utility Model Content

[0003] In view of this, the present invention provides an electric tool that can solve the problem of accidental motor start-up caused by accidental trigger switch contact in electric tools, thereby improving safety during use.

[0004] This utility model provides an electric tool having a working state and a standby state. The electric tool includes: a power supply circuit, a switch assembly, a detection circuit, a control circuit, a state holding circuit, and a motor, wherein the motor can output a torque of at least 1500 Nm.

[0005] The switching assembly is used to control the power output connected to the power circuit when triggered.

[0006] The detection circuit is connected to the switch assembly and the control circuit, and is used to detect the state change of the switch assembly. When the switch assembly is triggered, the detection circuit outputs a trigger signal to the control circuit.

[0007] The control circuit is connected to the state holding circuit and the motor. The control circuit is used to output a first control signal to the state holding circuit. The first control signal is configured to control the power tool to be in the working state or the standby state.

[0008] The state holding circuit is connected between the power supply circuit and the motor. When the level of the first control signal is a first level, the state holding circuit is in an off state, so that the power tool is in a standby state; and when the level of the first control signal is a second level, the state holding circuit is in an on state, so that the power tool is in a working state.

[0009] The control circuit is also used to control the motor to run in response to a received trigger signal in the working state, and not to respond when a single trigger signal is received in the standby state.

[0010] In some alternative embodiments, the switching assembly includes a trigger switch;

[0011] The detection circuit includes a first detection unit, which includes a first power supply terminal, a first resistor, and a first diode connected in series. The first diode is connected to one end of a trigger switch, and the other end of the trigger switch is grounded. The trigger signal input terminal of the control circuit is connected between the first resistor and the first diode. When the trigger switch is triggered, the level of the connection point changes, and the level change is used as the trigger signal.

[0012] In some alternative embodiments, in the standby state, if the control circuit detects at least two trigger signals within a first duration, it changes the first level of the first control signal to a second level to switch the standby state to the working state.

[0013] In some alternative embodiments, in the standby state, if the duration of the standby state reaches a second duration, the control circuit disconnects the power supply input of the power circuit to switch the standby state to a hibernation state.

[0014] In some alternative embodiments, if the control circuit does not receive the trigger signal within a third time period during the working state, it changes the second level of the first control signal to the first level to switch the working state to the standby state.

[0015] In some alternative embodiments, the state holding circuit includes a controlled switch, the controlled switch comprising:

[0016] The first terminal is connected to a preset voltage terminal, which is connected to the power supply circuit.

[0017] The second end is connected to the motor;

[0018] The control terminal, connected to the control circuit, is used to receive the first control signal, and when the level of the first control signal is a first level, the controlled switch is turned off; and when the level of the first control signal is a second level, the controlled switch is turned on.

[0019] In some alternative embodiments, the power tool includes a power switch.

[0020] In some alternative embodiments, the detection circuit includes a second detection unit, which includes a second diode and a second resistor; the cathode of the second diode is connected to one end of the power switch, the anode of the second diode is connected to the trigger signal input terminal of the control circuit, and the other end of the power switch is grounded; the first end of the second resistor is connected to a second power supply terminal, and the second end of the second resistor is connected to the connection point between the anode of the second diode and the trigger signal input terminal of the control circuit.

[0021] In some alternative embodiments, the power tool further includes a reminder circuit connected to the control circuit, the control circuit being configured to output a second control signal to control the reminder circuit to output a reminder signal when the second level is output.

[0022] In some alternative embodiments, the alert circuit includes an indicator light and / or a buzzer.

[0023] In some alternative embodiments, the power tool further includes a battery pack, and the power tool with the battery pack mounted weighs at least 8 kg.

[0024] In some alternative embodiments, the power tool further includes a working head and a mechanical assembly, the working head and the mechanical assembly being mechanically connected, the mechanical assembly being electrically connected to the motor, and the working head, the mechanical assembly, and the motor being located on the same axis.

[0025] As can be seen from the above, the power tool provided by one or more optional embodiments of this specification has the following beneficial technical effects:

[0026] The power tool has a working state and a standby state. Its motor torque is at least 1500 Nm. Through a detection circuit connected to a switching assembly and a control circuit, the detection circuit detects changes in the state of the switching assembly and outputs a trigger signal to the control circuit when the switching assembly is triggered. Through a connection between the control circuit and a state holding circuit, the control circuit outputs a first control signal to the state holding circuit. This first control signal is configured to control the power tool to be in either the working state or the standby state. Furthermore, by connecting the state holding circuit between the power supply circuit and the motor, the state holding circuit can respond to the first control signal at a first level, disconnecting the connection between the power supply circuit and the motor to enter the standby state, and respond to the first control signal at a second level, connecting the power supply circuit and the motor to enter the working state. In this circuit structure, the power supply circuit and the motor are physically isolated in the non-working state, ensuring that the motor cannot be powered and cannot start in the non-working state. This effectively suppresses accidental motor starting caused by accidental switch activation, improving the safety of using high-torque power tools. Attached Figure Description

[0027] The features and advantages of this utility model will be more clearly understood by referring to the accompanying drawings. The drawings are schematic and should not be construed as limiting the utility model in any way. In the drawings:

[0028] Figure 1a This is a three-dimensional structural diagram of the power tool provided in this embodiment of the utility model;

[0029] Figure 1b This is the three-dimensional structure of the power tool provided in this embodiment of the utility model. Figure 2 ;

[0030] Figure 1c This is the three-dimensional structure of the power tool provided in this embodiment of the utility model. Figure 3 ;

[0031] Figure 2 This is a schematic block diagram of the power tool provided in an embodiment of the present utility model;

[0032] Figure 3 This is a partial circuit diagram of the power tool provided in this embodiment of the utility model;

[0033] Figure 4 This is a schematic block diagram of an electric tool provided in another embodiment of the present invention;

[0034] Figure 5 This is a circuit diagram of the indicator light provided in this embodiment of the utility model;

[0035] Figure 6 This is a circuit diagram of the buzzer provided in an embodiment of the present invention.

[0036] Key reference numerals:

[0037] 100. Power tool; 101. Housing; 102. Output shaft; 110. Power supply circuit; 120. Switch assembly; 130. Detection circuit; 140. Control circuit; 150. Status holding circuit; 160. Motor; 170. Reminder circuit; 131. First detection unit; 132. Second detection unit; SW. Trigger switch; KEY. Power switch. Detailed Implementation

[0038] To make the technical solution and beneficial effects of this utility model more apparent and understandable, the technical solutions in the embodiments of this utility model are clearly and completely described below by listing specific examples. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0040] It is understood that the terms “first,” “second,” etc., as used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of this invention, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor. When “first” is described, it does not necessarily imply the existence of a “second”; and when “second” is discussed, it does not necessarily imply the existence of a first element, component, region, layer, or portion. As used herein, the singular forms “a,” “an,” and “the” may also be intended to include the plural forms unless the context clearly indicates otherwise. “A plurality” means two or more, unless otherwise explicitly specified. It should also be understood that the term “comprising,” when used in this specification, confirms the presence of the stated feature but does not exclude the presence or addition of one or more other features. As used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0041] It is understood that in the context of this utility model, "connection" means that there is an electrical signal or data transmission between the connected end and the connected end, which can be understood as "electrical connection", "communication connection", etc. In the context of this utility model, "A and B are directly connected" means that there are no other components between A and B except for wires.

[0042] In the field of power tools, especially handheld power tools such as electric wrenches, the motor is usually started by directly pressing the trigger switch. This poses a significant safety hazard, particularly for high-torque electric wrenches. When a user accidentally touches the trigger switch, the motor starts immediately and outputs high torque, which can easily lead to injury to the operator or damage to the equipment.

[0043] See Figures 1a-1c The diagram shows a three-dimensional structure of a power tool. This power tool can be an electric wrench, but it can also be a drill, hammer drill, or other handheld power tool. The power tool 100 includes a housing 101, a switch assembly, and modules such as a motor and control circuitry located within the housing 101. Figures 1a-1c (Not shown in the image), the motor is used to drive the output shaft 102 to rotate, and the motor can be a brushless motor.

[0044] The switching assembly may include a trigger switch SW and / or a power switch. For example, the trigger switch SW may be located in the handle position of the housing for easy one-handed operation. The power switch is used to turn the power to the entire power tool on or off and may be a separate physical switch, such as a power button.

[0045] The motor torque is at least 1500 Nm. For example, the motor torque can be 1800 Nm. The motor can drive the output shaft 102 of the power tool 100 to provide sufficient power to tighten large bolts or nuts, making the power tool 100 suitable for demanding applications such as industrial assembly, wind power, and rail transportation.

[0046] In some alternative embodiments, the power tool 100 includes a removable or built-in battery pack. Figures 1a-1c (Not shown in the image), the power tool 100 (battery pack) can weigh at least 8 kg.

[0047] The battery pack is used to provide power input to the power circuit of the power tool 100. This battery pack, serving as the main power source for the power tool, is preferably a lithium-ion battery pack, capable of supporting continuous operation of a high-power motor under high-load conditions.

[0048] In this embodiment, the power tool can be a vertical wrench, which is relatively heavy. Therefore, vertical wrenches often require the user to operate with both hands. Specifically, one hand (e.g., the left hand) is used to support the vertical wrench, and the other hand (e.g., the right hand) is used to pull the trigger. Specifically, the vertical wrench includes a main handle and a secondary handle. The main handle can be located at the rear of the vertical wrench, and the secondary handle can be located beside it. In this case, the vertical wrench can also have a reversing lever (which can be used to control the forward and reverse rotation of the vertical wrench). The reversing lever can be located at the main handle or elsewhere. For example, the reversing lever can be located on the side of the secondary handle.

[0049] Furthermore, the working head and mechanical components of the vertical wrench are mechanically connected, and the mechanical components are electrically connected to the motor. In a vertical wrench, the wrench, its mechanical components, and the working head are often located on an axis. This makes it easy for the user's hands to accidentally touch the wrench during use. Therefore, the power tools provided in one or more embodiments of this specification can reduce the risk of accidental contact with the wrench's handle.

[0050] See Figure 2 As shown, the power tool 100 includes a power supply circuit 110, a switch assembly 120, a detection circuit 130, a control circuit 140, a status holding circuit 150, and a motor 160.

[0051] The power tool 100 may have a housing, in which a power supply circuit 110, a detection circuit 130, a control circuit 140, a status holding circuit 150, and a motor 160 are housed; a switch assembly 120 may be disposed on the housing; the power supply circuit 110 is used to provide electrical power to the control circuit 140 and the motor 160.

[0052] The switch assembly 120 is connected to the power supply circuit 110, and the switch assembly 120 is used to control the power output connected to the power supply circuit 110 when it is triggered.

[0053] The power supply circuit 110 is used to distribute the voltage output from the battery pack to provide a stable operating power to electronic components such as the control circuit 140 and the motor.

[0054] The detection circuit 130 is connected to the switch assembly 120 and the control circuit 140, and is used to detect the state change of the switch assembly 120. When the switch assembly is triggered, the detection circuit outputs a trigger signal to the control circuit.

[0055] For example, the detection circuit 130 can detect changes in the on / off state of the circuit 130. For instance, the detection circuit 130 can detect the on / off state of the switch assembly 120 by monitoring voltage changes at the connection points of the switch assembly 120. For example, when the switch assembly 120 is on, the voltage at the corresponding connection point is pulled low; when the switch assembly 120 is off, the voltage at the corresponding connection point is maintained at a high level by a pull-up resistor, thereby generating a high-level trigger signal and a low-level trigger signal to be transmitted to the control circuit 140.

[0056] The control circuit 140 is connected to the state holding circuit 150 and the motor 160. The control circuit 140 is used to output a first control signal to the state holding circuit 150. The first control signal is configured to control the power tool to be in the working state or the standby state.

[0057] In standby mode, the control circuit 140 can respond to the received trigger signal to maintain or change the level of the first control signal.

[0058] The state holding circuit 150 is connected between the power supply circuit 110 and the motor 160. It is used to disconnect the power supply circuit 110 and the motor 160 in response to the first control signal level being at the first level, so that the power tool 100 is in standby mode; and to connect the power supply circuit 110 and the motor 160 in response to the first control signal level being at the second level, so that the power tool 100 is in working mode.

[0059] The control circuit 140 is also used to control the motor 160 to run in response to the received trigger signal when in operation.

[0060] The control circuit 140 may include a microcontroller unit (MCU, also known as a "single-chip microcomputer"), which may be a central processing unit (CPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), etc.

[0061] In some examples, the first level of the first control signal is low, such as 0V, and the second level of the first control signal is high, such as 3.3V. However, this is not the case; in other examples, the first level of the first control signal is high, and the second level of the first control signal is low.

[0062] The power tool 100 has different operating states, such as standby state, working state, and sleep state. In standby state, after the power tool 100 is powered on, the state holding circuit 150 disconnects the connection between the power supply circuit 110 and the motor 160, preventing the motor 160 from starting. In working state, the state holding circuit 150 connects the power supply circuit 110 to the motor 160, allowing the motor 160 to start. In sleep state, the power supply input to the power supply circuit 110 is completely disconnected, and the control circuit 140 stops working.

[0063] When the power tool 100 is in operation, the motor 160 can be started in response to the activation of the trigger switch under the control of the control circuit 140, and stopped in response to the deactivation of the trigger switch.

[0064] When a power tool is in standby mode, the control circuit will not start the motor even if the switch assembly is pressed once. The motor is only allowed to run when the switch is turned on, after a specific switch operation is detected (such as double-clicking the quick-press switch assembly) to switch the power tool from standby mode to operating mode.

[0065] In this embodiment, the power tool can enter standby mode after the system is powered on and the control circuit 140 starts working.

[0066] Please see Figure 3 , Figure 3 This is a partial circuit diagram of the power tool provided in this embodiment of the utility model. The power supply circuit 110 includes a battery pack (its positive terminal is B+), a capacitor C32, resistors R1, R2, R3, R4, and R5, transistors Q1 and Q2, Zener diodes ZD1, D1, D3, D4, and D8, capacitors C1, C2, C3, and C4, and a voltage converter U1.

[0067] When the battery pack is first plugged in, capacitor C32 is charged momentarily upon power-up. At this moment, the base of transistor Q2 (NPN type) is pulled high through resistor R1, turning on transistor Q2. After transistor Q2 turns on, its collector voltage changes the base voltage of transistor Q1 (PNP type) through the voltage divider network of resistors R3 and R4, turning on transistor Q1. After transistor Q1 turns on, the battery pack voltage is transmitted to the input of voltage converter U1 through transistor Q1. Voltage converter U1 outputs a stable 12V voltage, completing the power-on process.

[0068] When the power switch KEY is pressed (this power switch may be included in the switching assembly), the closure of the button KEY changes the base voltage of transistor Q1, turning on transistor Q1. After transistor Q1 turns on, the voltage of the battery pack is transmitted to the input terminal of voltage converter U1 through transistor Q1. Voltage converter U1 outputs a stable 12V voltage, completing the power-on process.

[0069] When the trigger switch SW is pressed (this trigger switch may be included in the switch assembly), the closing of the trigger switch SW changes the base voltage of transistor Q1, turning on transistor Q1. After transistor Q1 turns on, the voltage of the battery pack is transmitted to the input terminal of voltage converter U1 through transistor Q1. Voltage converter U1 outputs a stable 12V voltage, completing the power-on process.

[0070] After power-on is completed using any of the above power-on methods, the control circuit 140 begins operation. The control circuit 140 outputs a high-level keep_on signal to the power supply circuit 110, i.e., transmits the signal to... Figure 3 The anode of diode D3 is connected to the base of transistor Q2 via diode D3 and resistor R1, causing transistor Q2 to conduct. The keep_on signal ensures that the power supply circuit 110 continues to operate by providing a latching signal. At this time, the power tool 100 enters the standby state.

[0071] This utility model provides an electric tool with a working state and a standby state. The motor torque is at least 1800 Nm. A detection circuit is connected to a switch assembly and a control circuit. The detection circuit detects changes in the state of the switch assembly and outputs a trigger signal to the control circuit when the switch assembly is triggered. The control circuit is connected to a state holding circuit, which outputs a first control signal to the state holding circuit. This first control signal is configured to control the electric tool to be in either the working state or the standby state. The state holding circuit is connected between the power supply circuit and the motor. In response to the first control signal, the state holding circuit can be at a first level to disconnect the power supply circuit from the motor to enter the standby state, and at a second level to reconnect the power supply circuit to the motor to enter the working state. In this circuit structure, the power supply circuit and the motor are physically isolated in the non-working state, preventing the motor from being powered and started in the non-working state. This effectively suppresses accidental motor starting due to accidental switch activation, improving the safety of using high-torque electric tools.

[0072] In some embodiments, in the standby state, if the control circuit 140 receives at least two trigger signals within a first duration, it changes the first level of the first control signal to the second level to switch the standby state to the working state.

[0073] The control circuit 140 may have a first timer (not shown in the figure). If the switch component 120 is turned on at least twice within a first duration set by the first timer, the first level of the first control signal is changed to a second level.

[0074] In some examples, the control circuit 140 is used to respond to a trigger signal received in standby mode, and if the number of times the switching component 120 is turned on within a first duration set by the timer does not reach two, the level of the first control signal is maintained at the first level.

[0075] The first duration set for the first timer can be any duration between 1 second and 2 seconds, but is not limited to this.

[0076] When the user presses and releases the switch assembly 120 twice quickly within the first time period, the detection circuit 130 sends a corresponding trigger signal to the control circuit 140. After the control circuit 140 detects this double-click switch operation, it changes the first level of the first control signal to the second level to control the state holding circuit 150 to switch the power tool 100 from the standby state to the working state.

[0077] In this embodiment, the power tool 100 is in standby mode via the first timer in the control circuit 140. If the detection circuit 130 outputs a trigger signal to the control circuit 140 only once within the first duration set by the first timer, the control circuit 140 will not change the first level of the first control signal to the second level. This allows the state holding circuit to maintain the disconnection between the power supply circuit and the motor, preventing the motor 160 from receiving power and starting. Thus, when the user accidentally touches the switch assembly 120, accidental starting of the high-torque power tool can be avoided. Only when the user consciously performs a specific operation (such as quickly triggering twice) will the control circuit 140 control the state holding circuit 150 to connect the power supply circuit and the motor, switching the power tool 100 from standby mode to working mode, allowing the motor 160 to run in the working state. This ensures safety while maintaining ease of operation, making it suitable for power tools such as high-torque electric wrenches.

[0078] In some embodiments, in the standby state, if the duration of the standby state of the control circuit 140 reaches a second duration, the power supply input of the power circuit 110 is disconnected to switch the standby state to a hibernation state.

[0079] The control circuit 140 may have a second timer (not shown in the figure), which is used to disconnect the power supply input of the power circuit 110 when the duration of the standby state reaches the second duration set by the second timer, so as to switch the standby state to a sleep state.

[0080] The first duration of the second timer can be set to any duration between 30s and 60s, but is not limited to this.

[0081] When the power tool 100 is in standby mode and the control circuit 140 does not detect a switch operation through the detection channel 130 within the second duration set by the second timer, the control circuit 140 will disconnect the power supply input (e.g., battery pack) of the power circuit 110, causing the power tool 100 to enter a sleep state from the standby state. If the motor 160 needs to be started again at this time, the power circuit 110 of the power tool 100 needs to be powered on again, and after the power circuit 110 is powered on, it will first enter the standby state and then enter the working state.

[0082] For example, control circuit 140 outputs a low-level keep_on signal to power supply circuit 110, i.e., transmits the signal to... Figure 3 The anode of diode D3 in the transistor is transmitted to the base of transistor Q1 through diode D3 and resistor R1, causing transistor Q2 to turn off, and then Q1 to turn off, cutting off the voltage output of the battery pack.

[0083] In this embodiment, by using the second timer in the control circuit, unnecessary power consumption waste caused by the power tool being in standby mode for a long time is reduced, automatic power-off in standby mode is achieved, and battery life is extended.

[0084] In some embodiments, if the control circuit 140 does not receive a trigger signal within a third time period during the working state, it changes the second level of the first control signal to the first level to switch the working state to the standby state.

[0085] The control circuit 140 may have a third timer (not shown in the figure). The control circuit 140 is used to change the second level of the first control signal to the first level when the duration of the working state reaches the third duration set by the third timer, so as to switch the working state to the standby state if no trigger signal is received.

[0086] The third duration can be greater than or equal to the second duration. For example, the third duration set by the third timer can be any duration between 30s and 180s, but is not limited thereto.

[0087] When the power tool 100 is in the working state and the control circuit 140 does not detect the switch operation through the detection single channel 130 within the third time period set by the third timer, the control circuit will change the second level of the first control signal to the first level, so that the control state holding circuit 150 disconnects the connection between the power circuit and the motor, so that the power tool 100 switches from the working state back to the standby state.

[0088] In this embodiment, the working timeout protection function is realized by the third timer in the control circuit 140. When the power tool 100 is in working state but no one operates it for a long time, it switches back to standby state to further reduce safety hazards and also save energy.

[0089] Specifically, the control circuit 140 may include a microcontroller 141. Furthermore, a state holding circuit can also be integrated into the microcontroller 141. In addition, the microcontroller 141 can be connected to a drive circuit, which can be used to drive a motor.

[0090] Figure 3The keep_on, FIRE, and KEY2 terminals can all be connected to the microcontroller 141. The keep_on terminal provides voltage to the control terminal of transistor Q2, the FIRE terminal detects whether the trigger switch is activated, and the KEY2 terminal detects whether the power switch is activated. When all three terminals are connected to the microcontroller 141, the microcontroller 141 can determine whether to provide voltage to the control terminal of transistor Q2 through the keep_on terminal based on the state of the power tool 100, thereby determining whether to activate the motor 160. The first, second, and third timers can all be set within the microcontroller 141.

[0091] Specifically, in sleep mode (i.e., hibernation mode), the power tool 100 is powered off. After power-on, the microcontroller 141 provides a high-level signal to the control terminal of transistor Q2 through the keep_on terminal, which turns on transistor Q1, ensuring that the power supply circuit 110 continues to work and enters standby mode. In standby mode, if a single-trigger switch component 120 is detected, the microcontroller 141 controls the state holding circuit to keep the connection between the power supply circuit 110 and the motor 160 disconnected, so the motor 160 cannot start because it is not powered; if a rapid double-trigger switch component 120 is detected, the microcontroller 141 controls the state holding circuit to turn on the connection between the power supply circuit 110 and the motor 160, so the motor 160 is powered and the power tool 100 enters the working state; if the switch component 120 is not triggered for a long time, a low-level signal is provided to the control terminal of transistor Q2 through the keep_on terminal, which turns off transistor Q1, cuts off the voltage output of the battery pack, and the power tool 100 enters sleep mode. In the working state, if the microcontroller 141 detects that the power switch is in the conducting state and detects the triggering of the single-time switching component 120, the microcontroller 141 controls the motor 160 to work; if the microcontroller 141 detects that the power switch is in the conducting state and detects that the switching component 120 has not been triggered for a long time, it disconnects the connection between the power circuit 110 and the motor 160 and switches back to the standby state.

[0092] In some embodiments, see continue to see Figure 3As shown, the switch assembly 120 includes a trigger switch SW; the detection circuit 130 includes a first detection unit 131, which includes a first power supply terminal (e.g., output +5V), a first resistor R6, and a first diode D2 connected in series. The first diode D2 is connected to one end of the trigger switch SW, and the other end of the trigger switch SW is grounded. The trigger signal input terminal of the control circuit (e.g., a microcontroller 141) is connected between the first resistor R6 and the first diode D2. When the trigger switch SW is triggered, the level of the connection point changes so that the trigger signal input terminal receives the trigger signal.

[0093] Specifically, when the trigger switch SW is open, the first resistor R6 pulls the first connection point FIRE to a high level; when the trigger switch SW is closed, the first diode D2 conducts, pulling the first connection point FIRE to a low level. In this way, the first detection unit can accurately detect the on / off state change of the trigger switch SW and reliably transmit the corresponding trigger signal (high or low level) to the control circuit. Furthermore, the first diode D2 can prevent reverse current, protecting the circuit safety.

[0094] In some embodiments, see continue to see Figure 3 As shown, the detection circuit 130 includes a second detection unit 132, which includes a second diode D9 and a second resistor R42. The cathode of the second diode D9 is connected to the power switch KEY, and the anode of the second diode D9 is connected to the trigger signal input terminal of the control circuit (e.g., microcontroller 141). The first end of the second resistor R42 is connected to the power supply terminal (e.g., output +5V), and the second end of the second resistor R42 is connected to the connection point KEY2 between the anode of the second diode D9 and the trigger signal input terminal of the control circuit.

[0095] When the power switch KEY is off, the second resistor R42 pulls the second connection point KEY2 to a high level; when the second resistor R42 is closed, the second diode D9 conducts, pulling the second connection point KEY2 to a low level. In this way, the second detection unit can accurately detect the on / off state change of the power switch KEY and reliably transmit the information to the control circuit. Furthermore, the second diode D9 prevents reverse current, protecting the circuit.

[0096] Please see Figure 4 As shown, the power tool 100 also includes a reminder circuit 170, which is connected to the control circuit 140. The control circuit 140 is used to output a second control signal to control the reminder circuit 170 to output a reminder signal when the first control signal of the second level is output.

[0097] The reminder circuit 170 can be an indicator light or a buzzer. The indicator light can be placed in a conspicuous position such as the front or top of the housing, and the indicator light will illuminate when the power tool 100 enters the working state; the buzzer can emit a prompt sound when the power tool 100 enters the working state, so as to remind the user by sound that the power tool 100 is ready to work and the motor can be started directly by pressing the trigger for bolt tightening and loosening operations.

[0098] The detection circuit 130 sends a corresponding trigger signal to the control circuit 140. After the control circuit 140 detects this double-click switch operation, it outputs the first control signal at the second level to control the connection between the power circuit and the motor in the state holding circuit 150. At the same time, it immediately sends a reminder control signal to the reminder circuit 170 to remind the user that the power tool 100 is ready to work, which can further enhance safety.

[0099] See Figure 5 As shown, Figure 5 This is a circuit diagram of the indicator light provided in this embodiment of the utility model. The control circuit 140 is connected to the cathode of the indicator light LED1 through a resistor R10 and a transistor Q9. The anode of the indicator light LED1 is connected to the power supply terminal VLED through a resistor R9. The control circuit 140 outputs a Lamp signal to pull up the base voltage of the transistor Q9, turning on the transistor Q9 and causing the indicator light LED1 to emit light (e.g., white light) to remind the user that the power tool has entered the working state and can be started directly by pressing the trigger. The Lamp signal can be a square wave pulse signal to control the indicator light LED1 to blink.

[0100] See Figure 6 As shown, Figure 6 This is a circuit diagram of the buzzer provided in this embodiment of the utility model. The control circuit 140 is connected to one end of the buzzer speaker through resistor R55 and transistor Q10. The other end of the buzzer speaker is connected to the power supply terminal VLED through resistor R49. The control circuit outputs a SPEAK signal to pull up the base voltage of transistor Q10, turning on transistor Q10 and causing the buzzer speaker to output a sound to remind that the power tool has entered the working state and can be started directly by pressing the trigger. The SPEAK signal can be a square wave pulse signal to control the buzzer speaker to sound multiple times.

[0101] For example, when the power tool is in a sleep state, after the system is powered on, the power tool enters a standby state. If, within a second duration (e.g., 30 seconds), it is detected whether the user has double-clicked the start switch (or whether the switch assembly 120 has been turned on twice within a first duration (e.g., 1 second)). If not detected, the power tool is triggered to enter a sleep state. If detected, the power tool is triggered to enter a working state (or "ready state"), with the light flashing or the buzzer beeping multiple times. Within a third duration (e.g., 30 seconds), it is detected whether the user has pressed the trigger switch. If so, the motor is controlled to run; otherwise, the power tool is triggered to enter a standby state.

[0102] In some embodiments, the state holding circuit 150 includes a controlled switch (not shown in the figure), the controlled switch including a first terminal, a second terminal and a control terminal; the first terminal is connected to a preset voltage terminal, the preset voltage terminal is connected to the power supply circuit 110; the second terminal is connected to the motor 160; the control terminal is connected to the control circuit 140 for receiving the first control signal.

[0103] In some examples, the controlled switch can be a MOSFET or a relay. Taking an N-type MOSFET as an example, when the first control signal is at a first level (e.g., low level), the MOSFET is turned off, disconnecting the power supply circuit 110 from the motor 160 and maintaining the standby state; when the first control signal is at a second level (e.g., high level), the MOSFET is turned on, connecting the power supply circuit 110 to the motor 160 and switching the standby state to the working state.

[0104] In some alternative embodiments, the second terminal of the controlled switch can be connected to the motor via a motor drive circuit. The motor drive circuit includes multiple switching transistors, and when the power tool is in operation, the control circuit can control the on / off state of the multiple switching transistors respectively to control the operation of the motor.

[0105] In this embodiment, by setting a controlled switch in the state holding circuit 150, physical isolation between the power supply circuit 110 and the motor 160 is achieved, ensuring that the motor 160 cannot be powered and cannot start in the standby state. This fundamentally solves the problem of accidental motor start-up caused by accidental switch contact in traditional power tools, greatly improving the safety and reliability of operation, and is especially suitable for power tools such as high-torque electric wrenches.

[0106] In some alternative embodiments, the state holding circuit 150 may also be integrated into the motor drive circuit, i.e., the controlled switch is located in the motor drive circuit.

[0107] In some alternative embodiments, the state holding circuit 150 may also be located within the microcontroller 141. When the controlled switch is off, the connection between the power supply circuit 110 and the motor 160 is broken, and the motor is not powered. When the controlled switch is on, the connection between the power supply circuit 110 and the motor 160 is established, and the motor is powered.

[0108] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this disclosure (including the claims) is limited to these examples; within the framework of this disclosure, the technical features of the above embodiments or different embodiments can also be combined, and there are many other variations of different aspects of one or more embodiments of this specification as described above, which are not provided in detail for the sake of brevity.

[0109] Additionally, to simplify the description and discussion, and to avoid obscuring one or more embodiments of this specification, well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Furthermore, the apparatus may be illustrated in block diagram form to avoid obscuring one or more embodiments of this specification, and this also takes into account the fact that the details of implementation of these block diagram apparatuses are highly dependent on the platform on which one or more embodiments of this specification will be implemented (i.e., these details should be fully understood by those skilled in the art). While specific details (e.g., circuits) have been set forth to describe exemplary embodiments of this disclosure, it will be apparent to those skilled in the art that one or more embodiments of this specification may be implemented without these specific details or with variations thereof. Therefore, these descriptions should be considered illustrative rather than restrictive.

[0110] As used herein, the term "circuit" can include hardware configured to perform the functions described herein. In some embodiments, each corresponding "circuit" can include a machine-readable medium for configuring hardware to perform the functions described herein. A circuit can be embodied as one or more circuit components, including but not limited to processing circuitry, network interfaces, peripheral devices, input devices, output devices, sensors, etc. In some embodiments, a circuit can take one or more forms. Further analog circuitry, electronic circuitry (e.g., integrated circuits (ICs), discrete circuitry, system-on-a-chip (SoC) circuitry, etc.), telecommunications circuitry, hybrid circuitry, and any other type of "circuit" are also included. In this respect, "circuit" can include any type of component for implementing or facilitating the implementation of the operations described herein. For example, a circuit described herein can include one or more transistors, logic gates (e.g., NAND, AND, NOR, OR, XOR, NOT, XNOR, etc.), resistors, multiplexers, registers, capacitors, inductors, diodes, wiring, etc.

[0111] The “circuit” may also include one or more processors communicatively coupled to one or more memories or memory devices. In this respect, the one or more processors may execute instructions stored in memory or may execute instructions accessible to the one or more processors. In some embodiments, the one or more processors may be implemented in various ways. The one or more processors may be constructed in a manner sufficient to perform at least the operations described herein. In some embodiments, the one or more processors may be shared by multiple circuits (e.g., circuit A and circuit B may include or otherwise share the same processor, which, in some exemplary embodiments, may execute instructions stored or otherwise accessed via different regions of memory). Alternatively or additionally, the one or more processors may be configured to perform or otherwise perform certain operations independently of one or more coprocessors. In other example embodiments, two or more processors may be coupled via a bus to enable independent, parallel, pipelined, or multithreaded instruction execution. Each processor may be implemented as one or more general-purpose processors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components configured to perform operations from memory. The one or more processors may take the form of a single-core processor, a multi-core processor (e.g., a dual-core processor, a triple-core processor, a quad-core processor, etc.), a microprocessor, etc. In some embodiments, one or more processors may be external to the device; for example, one or more processors may be remote processors (e.g., cloud-based processors). Alternatively or additionally, one or more processors may be internal to the device and / or local. In this respect, a given circuit or its components may be located locally (e.g., as part of a local server, local computing system, etc.) or remotely (e.g., as part of a remote server, such as a cloud-based server). For this purpose, a “circuit” as described herein may include components distributed in one or more locations.

[0112] Although this disclosure has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. One or more embodiments of this specification are intended to cover all such substitutions, modifications, and variations falling within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments of this specification should be included within the scope of protection of this disclosure.

Claims

1. A power tool, characterized in that, The power tool has a working state and a standby state. The power tool includes: a power supply circuit, a switching assembly, a detection circuit, a control circuit, a state holding circuit, and a motor, wherein the motor can output a torque of at least 1500 Nm. The switching assembly is used to control the power output connected to the power circuit when triggered. The detection circuit is connected to the switch assembly and the control circuit, and is used to detect the state change of the switch assembly. When the switch assembly is triggered, the detection circuit outputs a trigger signal to the control circuit. The control circuit is connected to the state holding circuit and the motor. The control circuit is used to output a first control signal to the state holding circuit. The first control signal is configured to control the power tool to be in the working state or the standby state. The state holding circuit is connected between the power supply circuit and the motor. When the level of the first control signal is a first level, the state holding circuit is in an off state, so that the power tool is in a standby state; and when the level of the first control signal is a second level, the state holding circuit is in an on state, so that the power tool is in a working state. The control circuit is also used to control the motor to run in response to a received trigger signal in the working state, and not to respond when a single trigger signal is received in the standby state.

2. The power tool according to claim 1, characterized in that, The switching assembly includes a trigger switch; The detection circuit includes a first detection unit, which includes a first power supply terminal, a first resistor, and a first diode connected in series. The first diode is connected to one end of a trigger switch, and the other end of the trigger switch is grounded. The trigger signal input terminal of the control circuit is connected between the first resistor and the first diode. When the trigger switch is triggered, the voltage level at the connection point between the first resistor and the first diode changes, and the control circuit uses the voltage level change as the trigger signal.

3. The power tool according to claim 1, characterized in that, In standby mode, if the control circuit detects at least two trigger signals within a first duration, it changes the first level of the first control signal to the second level to switch the standby mode to the working mode.

4. The power tool according to claim 3, characterized in that, In standby mode, if the duration of the standby mode reaches a second duration, the control circuit disconnects the power supply input of the power circuit to switch the standby mode to a hibernation mode.

5. The power tool according to claim 1, characterized in that, If the control circuit does not receive the trigger signal within a third time period during the working state, it changes the second level of the first control signal to the first level to switch the working state to the standby state.

6. The power tool according to claim 1, characterized in that, The state holding circuit includes a controlled switch, the controlled switch comprising: The first terminal is connected to a preset voltage terminal, which is connected to the power supply circuit. The second end is connected to the motor; The control terminal, connected to the control circuit, is used to receive the first control signal, and when the level of the first control signal is a first level, the controlled switch is turned off; and when the level of the first control signal is a second level, the controlled switch is turned on.

7. The power tool according to claim 1, characterized in that, The power tool includes a power switch.

8. The power tool according to claim 7, characterized in that, The detection circuit includes a second detection unit, which includes a second diode and a second resistor. The cathode of the second diode is connected to one end of the power switch, and the anode of the second diode is connected to the trigger signal input terminal of the control circuit. The other end of the power switch is grounded. The first end of the second resistor is connected to the second power supply terminal, and the second end of the second resistor is connected to the connection point between the anode of the second diode and the trigger signal input terminal of the control circuit.

9. The power tool according to claim 1, characterized in that, The power tool also includes a reminder circuit, which is connected to the control circuit. The control circuit is used to output a second control signal when outputting a second level to control the reminder circuit to output a reminder signal.

10. The power tool according to claim 9, characterized in that, The alert circuit includes an indicator light and / or a buzzer.

11. The power tool according to claim 1, characterized in that, The power tool also includes a battery pack, and the power tool with the battery pack installed weighs at least 8 kg.

12. The power tool according to claim 1, characterized in that, The power tool also includes a working head and a mechanical assembly, the working head and the mechanical assembly being mechanically connected, the mechanical assembly being electrically connected to the motor, and the working head, the mechanical assembly and the motor being located on the same axis.

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