Trigger circuit and electric tool

Abstract

The utility model discloses a trigger circuit and an electric tool, and relates to the field of power supply, the trigger circuit comprises a main switch, an auxiliary switch, a first controllable switch, a first capacitor, a switch control circuit and a capacitor control circuit, and the on-off state of the auxiliary switch is consistent with the on-off state of the main switch. When the main switch and the auxiliary switch are closed, the capacitor control circuit charges the first capacitor, and then the switch control circuit controls the first controllable switch to be switched on, so that the power supply end of the electric tool is powered on. When the electric tool is abnormal and enters a dormant state, namely the enabling end is set to be a second level, the main switch and the auxiliary switch are disconnected, the first capacitor discharges so as to be recharged after the main switch is closed, and the switch control circuit controls the first controllable switch to be disconnected; therefore, power can be quickly supplied to the electric tool again after the main switch is closed again, and the electric tool can enter a dormant state when abnormal, so that power consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the field of power supply, in particular to a trigger circuit and an electric tool. Background Art

[0002] When a battery pack is used to power an electric tool in the related art, a trigger circuit is usually provided in the electric tool. When the main switch in the trigger circuit is closed, the controllable switch between the positive electrode of the battery pack and the power supply end of the electric tool in the trigger circuit is closed, so that the battery pack can power the electric tool. In order to ensure that the main switch in the trigger circuit can be re-closed when the electric tool is abnormal, the related art will not control the electric tool to enter a dormant state even if the electric tool is working abnormally, causing the electric tool to continue to consume the electric energy in the battery pack until the battery pack is under-voltage, and the overall power consumption is very large. Utility Model Content

[0003] The purpose of the utility model is to provide a trigger circuit and an electric tool, which can quickly power the electric tool by closing a main switch when the electric tool is normal, and can quickly restore power to the electric tool by disconnecting and then closing the main switch when the electric tool is abnormal and enters a dormant state, and can also reduce power consumption.

[0004] In order to solve the above technical problems, the utility model provides a trigger circuit, including a main switch, an auxiliary switch, a first controllable switch, a first capacitor, a switch control circuit and a capacitor control circuit;

[0005] The switch control circuit includes a voltage output terminal, a first input terminal and a second input terminal, wherein the voltage output terminal is connected to the control terminal of the first controllable switch, the first input terminal is connected to the enable terminal of the electric tool, and the second input terminal is connected to the first capacitor, so as to turn on the first controllable switch after the first capacitor is charged or when the enable terminal is at a first level, and turn off the first controllable switch when the first capacitor is not charged and the enable terminal is at a second level, and the second level is different from the first level;

[0006] The capacitor control circuit includes a first terminal, a second terminal and a third terminal, wherein the first terminal is connected to the auxiliary switch, the second terminal is connected to the battery pack, and the third terminal is connected to the first capacitor, so as to charge the first capacitor through the battery pack after the auxiliary switch is closed, and discharge the first capacitor after the auxiliary switch is opened;

[0007] The main switch is arranged between the battery pack and the motor drive circuit of the power tool, the first end and the second end of the first controllable switch are connected to the battery pack and the power supply end of the power tool respectively, and the switching state of the auxiliary switch is consistent with the switching state of the main switch.

[0008] Optionally, the capacitor control circuit includes a second controllable switch, a first resistor, a second resistor and a capacitor discharge circuit;

[0009] The first end of the second controllable switch is connected to the first end of the battery pack and the first end of the first resistor respectively, the second end of the second controllable switch is connected to the first end of the first capacitor, and the control end of the second controllable switch is connected to the second end of the first resistor and the first end of the second resistor respectively;

[0010] The second end of the second resistor is connected to the first end of the auxiliary switch, and the second end of the auxiliary switch is grounded; the first end of the first capacitor is connected to the capacitor discharge circuit.

[0011] Optionally, the capacitor control circuit further includes a charging current limiting circuit arranged between the first end of the first capacitor and the second end of the second controllable switch.

[0012] Optionally, the charging current limiting circuit is a third resistor.

[0013] Optionally, the capacitor discharge circuit is a fourth resistor, a first end of the fourth resistor is connected to the first end of the first capacitor, and a second end of the fourth resistor is grounded.

[0014] Optionally, the switch control circuit includes a third controllable switch, a fifth resistor, a sixth resistor and a seventh resistor;

[0015] The control end of the third controllable switch is connected to the enable end of the electric tool and the first end of the fifth resistor, the first end of the third controllable switch is connected to the second end of the fifth resistor and the common end of the connection is grounded, the second end of the third controllable switch is connected to the first end of the seventh resistor, the second end of the seventh resistor is connected to the first end of the sixth resistor and the control end of the first controllable switch, and the second end of the sixth resistor is connected to the first end of the first controllable switch.

[0016] Optionally, the switch control circuit further includes an eighth resistor, and the eighth resistor is arranged between the enable end of the electric tool and the control end of the third controllable switch.

[0017] Optionally, the first controllable switch is a PNP transistor, the second controllable switch is a PMOS, and the third controllable switch is an NPN transistor;

[0018] The emitter of the PNP transistor serves as the first end of the first controllable switch, the collector of the PNP transistor serves as the second end of the first controllable switch, and the base of the PNP transistor serves as the control end of the first controllable switch;

[0019] The emitter of the NPN transistor serves as the first end of the third controllable switch, the collector of the NPN transistor serves as the second end of the third controllable switch, and the base of the NPN transistor serves as the control end of the third controllable switch;

[0020] The gate of the PMOS serves as a control terminal of the second controllable switch, the source of the PMOS serves as a first terminal of the second controllable switch, and the drain of the PMOS serves as a second terminal of the second controllable switch.

[0021] Optionally, a second capacitor is further included, a common end of the main switch connected to the motor drive circuit is connected to a first end of the second capacitor, and a second end of the second capacitor is grounded.

[0022] In order to solve the above technical problems, the present application also provides an electric tool, comprising any one of the above trigger circuits.

[0023] The beneficial effect of the utility model is to provide a trigger circuit and an electric tool, including a main switch, an auxiliary switch, a first controllable switch, a first capacitor, a switch control circuit and a capacitor control circuit, and the switch state of the auxiliary switch is consistent with the switch state of the main switch. When the main switch and the auxiliary switch are closed, the capacitor control circuit charges the first capacitor, and the switch control circuit then controls the first controllable switch to be turned on, so that the power supply end of the electric tool is powered. When the electric tool is abnormal and enters a dormant state, that is, the enable end is set to the second level, the main switch and the auxiliary switch are disconnected, the first capacitor is discharged so as to be recharged after the main switch is closed, and the switch control circuit then controls the first controllable switch to be disconnected. It can be seen that after the main switch is closed again, the electric tool can be quickly powered again, and the electric tool can enter a dormant state when it is abnormal, thereby reducing power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 The present invention provides a circuit diagram of a trigger circuit. DETAILED DESCRIPTION

[0026] The core of the utility model is to provide a trigger circuit and an electric tool. When the electric tool is normal, the electric tool can be powered quickly by closing the main switch. When the electric tool is abnormal and enters a sleep state, the main switch can be disconnected and then closed again to quickly restore power to the electric tool and reduce power consumption.

[0027] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] Please refer to Figure 1 , Figure 1 A circuit diagram of a trigger circuit provided by the utility model. The trigger circuit includes a main switch SW2, an auxiliary switch SW1, a first controllable switch M1, a first capacitor C1, a switch control circuit 2 and a capacitor control circuit 1;

[0029] The switch control circuit 2 includes a voltage output terminal, a first input terminal and a second input terminal, wherein the voltage output terminal is connected to the control terminal of the first controllable switch M1, the first input terminal is connected to the enable terminal of the electric tool, and the second input terminal is connected to the first capacitor C1, so as to turn on the first controllable switch M1 after the first capacitor C1 is charged or when the enable terminal is at a first level, and to turn off the first controllable switch M1 when the first capacitor C1 is not charged and the enable terminal is at a second level, and the second level is different from the first level;

[0030] The capacitor control circuit 1 includes a first terminal, a second terminal and a third terminal, wherein the first terminal is connected to the auxiliary switch SW1, the second terminal is connected to the battery pack, and the third terminal is connected to the first capacitor C1, so as to charge the first capacitor C1 through the battery pack after the auxiliary switch SW1 is closed, and discharge the first capacitor C1 after the auxiliary switch SW1 is opened;

[0031] The main switch SW2 is arranged between the battery pack and the motor drive circuit of the power tool. The first end and the second end of the first controllable switch M1 are connected to the battery pack and the power supply end of the power tool respectively. The switching state of the auxiliary switch SW1 is consistent with the switching state of the main switch SW2.

[0032] In the related art, when a trigger circuit is used to control whether a battery pack supplies power to an electric tool, in order to ensure that the main switch SW2 in the trigger circuit can be closed again when the electric tool is abnormal, the battery pack will not be controlled to enter a dormant state even if the electric tool is abnormal, resulting in the electric tool continuing to consume the electric energy in the battery pack until the battery pack is undervoltage, and the overall power consumption is very large. To this end, the utility model provides a trigger circuit, including a main switch SW2, an auxiliary switch SW1, a first controllable switch M1, a first capacitor C1, a switch control circuit 2, and a capacitor control circuit 1. The capacitor control circuit 1 is set to charge the first capacitor C1 using the battery pack when the auxiliary switch SW1 is closed, so that the switch control circuit 2 turns the first controllable switch M1 on to enable the battery pack to supply power to the electric tool; the capacitor control circuit 1 discharges the first capacitor C1 when the auxiliary switch SW1 is disconnected, so that the first capacitor C1 can be charged normally when the auxiliary switch SW1 is closed again next time, thereby ensuring that the battery pack can quickly resume power supply to the electric tool. It can be seen that the electric tool can normally enter a dormant state when it is abnormal, and will not affect the process of the battery pack restoring power to the electric tool, thereby reducing power consumption.

[0033] For details, please refer to Figure 1 , Figure 1 A circuit diagram of a trigger circuit provided by the utility model, Figure 1 B+ is the positive electrode of the battery pack, P+ is the terminal connected to the motor drive circuit, EN is the enable terminal of the power tool, and VCC is the power supply terminal of the power tool. The switch states of the main switch SW2 and the auxiliary switch SW1 in the trigger circuit are consistent. When the user closes the main switch SW2, the auxiliary switch SW1 is also closed; the first and second ends of the capacitor control circuit 1 are respectively connected to the auxiliary switch SW1 and the battery pack, so that after the auxiliary switch SW1 is closed, the first capacitor C1 is charged through the battery pack; the second input end and the voltage output end of the switch control circuit 2 are respectively connected to the first capacitor C1 and the control end of the first controllable switch M1, so that after the first capacitor C1 is charged, the first controllable switch M1 is turned on, so that the branch between the battery pack and the power supply terminal of the power tool is turned on, and the battery pack supplies power to the power tool, that is, the power tool is powered. The first input terminal of the switch control circuit 2 is also connected to the enable terminal of the power tool. After the power tool is powered on, its enable terminal is set to the first level. Even if the main switch SW2 is disconnected and the auxiliary switch SW1 is disconnected accordingly, the switch control circuit 2 can keep the first controllable switch M1 in the on state, so that the battery pack continues to power the power tool.

[0034] When an abnormality occurs in the power tool, the power tool will actively or passively enter a dormant state, and the enable end of the power tool becomes the second level. When the user disconnects the main switch SW2, the auxiliary switch SW1 is disconnected accordingly, and the capacitor control circuit 1 discharges the first capacitor C1 after the auxiliary switch SW1 is disconnected. When the first capacitor C1 is not charged and the enable end of the power tool is at the second level, the switch control circuit 2 disconnects the first controllable switch M1, so that the branch between the battery pack and the power supply end of the power tool is disconnected. That is, the power tool will not continue to consume the electric energy in the battery pack when an abnormality occurs. In addition, since the auxiliary switch SW1 is also disconnected after the user disconnects the main switch SW2, and the capacitor control circuit 1 discharges the first capacitor C1, after the user recloses the main switch SW2 and the auxiliary switch SW1 is also closed, the capacitor control circuit 1 can quickly restore the charging of the first capacitor C1, thereby causing the switch control circuit 2 to quickly turn on the first controllable switch M1, and finally restore the battery pack to power the power tool.

[0035] It should be noted that the main switch SW2 and the auxiliary switch SW1 in the trigger circuit provided by the present application are irreversible switches, and the switch state of the auxiliary switch SW1 is consistent with the switch state of the main switch SW2. When the user triggers the main switch SW2 to close it, the auxiliary switch SW1 is also closed. When the user triggers the main switch SW2 again to open it, the auxiliary switch SW1 is also opened. The present application does not specifically limit the specific structure of the main switch SW2 and the auxiliary switch SW1. For example, the main switch SW2 and the auxiliary switch SW1 are both controllable switches. When the processing module in the power tool detects that the main switch SW2 is closed, the auxiliary switch SW1 is controlled to be closed; or the main switch SW2 and the auxiliary switch SW1 are different coils of the same relay.

[0036] In summary, the utility model provides a trigger circuit, including a main switch SW2, a sub-switch SW1, a first controllable switch M1, a first capacitor C1, a switch control circuit 2 and a capacitor control circuit 1, and the switch state of the sub-switch SW1 is consistent with the switch state of the main switch SW2. When the main switch SW2 and the sub-switch SW1 are closed, the capacitor control circuit 1 charges the first capacitor C1, and the switch control circuit 2 then controls the first controllable switch M1 to be turned on, so that the power supply end of the power tool is powered. When the power tool is abnormal and enters a dormant state, that is, the enable end is set to the second level, the main switch SW2 and the sub-switch SW1 are disconnected, the first capacitor C1 is discharged so as to be recharged after the main switch SW2 is closed, and the switch control circuit 2 then controls the first controllable switch M1 to be disconnected. It can be seen that after the main switch SW2 is closed again, the power supply for the power tool can be quickly re-powered, and the power tool can enter a dormant state when it is abnormal, thereby reducing power consumption.

[0037] Based on the above embodiments:

[0038] As an optional embodiment, the capacitor control circuit 1 includes a second controllable switch M2, a first resistor R1, a second resistor R2 and a capacitor discharge circuit;

[0039] The first end of the second controllable switch M2 is connected to the battery pack and the first end of the first resistor R1 respectively, the second end of the second controllable switch M2 is connected to the first end of the first capacitor C1, and the control end of the second controllable switch M2 is connected to the second end of the first resistor R1 and the first end of the second resistor R2 respectively;

[0040] The second end of the second resistor R2 is connected to the first end of the auxiliary switch SW1 , and the second end of the auxiliary switch SW1 is grounded; the first end of the first capacitor C1 is connected to the capacitor discharge circuit.

[0041] Please refer to Figure 1 , Figure 1 A circuit diagram of a trigger circuit provided by the utility model. The capacitor control circuit 1 is responsible for charging the first capacitor C1 through the battery pack when the auxiliary switch SW1 is closed, and discharging the first capacitor C1 when the auxiliary switch SW1 is disconnected so as to recharge the first capacitor C1 after the main switch SW2 and the auxiliary switch SW1 are closed. In this embodiment, the capacitor control circuit 1 includes a second controllable switch M2, a first resistor R1, a second resistor R2 and a capacitor discharge circuit. Among them, the first end of the second controllable switch M2 is connected to the battery pack, and the second end is connected to the first end of the first capacitor C1. When the second controllable switch M2 is turned on, the battery pack can supply power to the first capacitor C1. The first end of the first capacitor C1 is also connected to the capacitor discharge circuit, and when the second controllable switch M2 is disconnected, the first capacitor C1 can be discharged through the capacitor discharge circuit. The control end of the second controllable switch M2 is respectively connected to the second end of the first resistor R1 and the first end of the second resistor R2, the first end of the first resistor R1 is also connected to the battery pack, and the second end of the second resistor R2 is grounded through the auxiliary switch SW1. Therefore, when the auxiliary switch SW1 is closed, a voltage difference is formed between the first end and the control end of the second controllable switch M2 by the voltage divider circuit formed by the first resistor R1 and the second resistor R2, so that the second controllable switch M2 is turned on, and the capacitor control circuit 1 charges the first capacitor C1 through the battery pack when the auxiliary switch SW1 is closed; when the auxiliary switch SW1 is disconnected, there is no voltage difference between the first end and the control end of the second controllable switch M2, so that the second controllable switch M2 is disconnected, and at this time the first capacitor C1 is discharged through the capacitor discharge circuit, thereby realizing the purpose of the capacitor control circuit 1 discharging the first capacitor C1 when the auxiliary switch SW1 is disconnected so as to charge the first capacitor C1 after the main switch SW2 and the auxiliary switch SW1 are closed.

[0042] In addition, a charging current limiting circuit may be provided between the first end of the first capacitor C1 and the second end of the second controllable switch M2. The charging current limiting circuit includes but is not limited to: Figure 1The third resistor R3 shown in the figure can improve the safety of the capacitor control circuit 1 when charging the first capacitor C1, thereby improving the reliability of the trigger circuit and the power tool as a whole during operation. The capacitor discharge circuit in the capacitor control circuit 1 can be a fourth resistor R4, a first end of the fourth resistor R4 is connected to the first end of the first capacitor C1, and a second end of the fourth resistor R4 is grounded.

[0043] As an optional embodiment, the switch control circuit 2 includes a third controllable switch M3, a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7;

[0044] The control end of the third controllable switch M3 is connected to the enable end of the electric tool and the first end of the fifth resistor R5, the first end of the third controllable switch M3 is connected to the second end of the fifth resistor R5 and the common end of the connection is grounded, the second end of the third controllable switch M3 is connected to the first end of the seventh resistor R7, the second end of the seventh resistor R7 is connected to the first end of the sixth resistor R6 and the control end of the first controllable switch M1, and the second end of the sixth resistor R6 is connected to the first end of the first controllable switch M1.

[0045] Please refer to Figure 1 , Figure 1 A circuit diagram of a trigger circuit provided by the utility model. The switch control circuit 2 is responsible for turning on the first controllable switch M1 after the first capacitor C1 is charged or when the enable end of the electric tool is at the first level; when the first capacitor C1 is not charged and the enable end of the electric tool is at the second level, the first controllable switch M1 is turned off. In this embodiment, the switch control circuit 2 includes a third controllable switch M3, a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7. The two ends of the fifth resistor R5 are respectively connected to the control end and the first end of the third controllable switch M3. When the first capacitor C1 is charged, the third controllable switch M3 is turned on, and a voltage difference is further formed between the first end and the control end of the first controllable switch M1 through the seventh resistor R7 and the eighth resistor R8, so that the first controllable switch M1 is turned on; similarly, when the electric tool is powered on, the electric tool sets its enable end to the first level (in this embodiment, the first level is a high level), so that the third controllable switch M3 and the first controllable switch M1 are turned on in sequence. When an abnormality occurs in the electric tool, it enters a sleep state and sets its enable terminal to the second level (in this embodiment, the second level is a low level). Since the main switch SW2 and the auxiliary switch SW1 are both disconnected, the first capacitor C1 is discharged. At this time, the conduction conditions of the third controllable switch M3 and the first controllable switch M1 cannot be met, that is, the first controllable switch M1 is disconnected.

[0046] In summary, this embodiment provides a switch control circuit 2 with a relatively simple circuit structure, and can realize the function of turning on the first controllable switch M1 after the first capacitor C1 is charged or when the enable end of the power tool is at the first level; and turning off the first controllable switch M1 when the first capacitor C1 is not charged and the enable end of the power tool is at the second level.

[0047] More specifically, the first controllable switch M1 is a PNP transistor, the second controllable switch M2 is a PMOS, and the third controllable switch M3 is an NPN transistor; the emitter of the PNP transistor serves as the first end of the first controllable switch M1, the collector of the PNP transistor serves as the second end of the first controllable switch M1, and the base of the PNP transistor serves as the control end of the first controllable switch M1; the emitter of the NPN transistor serves as the first end of the third controllable switch M3, the collector of the NPN transistor serves as the second end of the third controllable switch M3, and the base of the NPN transistor serves as the control end of the third controllable switch M3; the gate of the PMOS serves as the control end of the second controllable switch M2, the source of the PMOS serves as the first end of the second controllable switch M2, and the drain of the PMOS serves as the second end of the second controllable switch M2.

[0048] In addition, Figure 1 As an example, when the power tool works abnormally and enters the sleep state, the power tool is powered off. When the main switch SW2 is closed, only Figure 1 The leakage current of the second capacitor C2 and the leakage current generated by the first resistor R1 and the second resistor R2 to the ground are reduced. Since the first resistor R1 and the second resistor R2 can be made of megohm-level resistors, the overall leakage current of the power tool is very small and the power consumption is very small.

[0049] In addition, the switch control circuit 2 further includes an eighth resistor R8, which is arranged between the enable terminal of the electric tool and the control terminal of the third controllable switch M3, so as to further improve the safety of the trigger circuit.

[0050] As an optional embodiment, a second capacitor C2 is further included, a common end of the main switch SW2 connected to the motor drive circuit is connected to a first end of the second capacitor C2, and a second end of the second capacitor C2 is grounded.

[0051] Considering that the motor in the power tool also needs power supply, it is also necessary to control the motor drive circuit. Therefore, in this embodiment, the main switch SW2 is also connected to the motor drive circuit, and a second capacitor C2 for motor control energy storage and filtering is also provided. When the main switch SW2 is closed, the battery pack provides power to the motor drive circuit through the second capacitor C2.

[0052] In order to solve the above technical problems, the present application also provides an electric tool, comprising any one of the above trigger circuits.

[0053] For a detailed description of the electric tool provided in this application, please refer to the above-mentioned trigger circuit embodiment. The electric tool includes but is not limited to a lawn mower, a hair dryer, etc., which will not be described in detail in this application.

[0054] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other. It should also be noted that in this specification, relational terms such as first and second, etc. are only used to distinguish one entity from another entity, and do not necessarily require or imply any actual relationship or order between these entities. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that an article or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the presence of other identical elements in the article or device including the elements.

[0055] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A trigger circuit, characterized in that: It includes a main switch, a secondary switch, a first controllable switch, a first capacitor, a switch control circuit and a capacitor control circuit; The switch control circuit includes a voltage output terminal, a first input terminal and a second input terminal, wherein the voltage output terminal is connected to the control terminal of the first controllable switch, the first input terminal is connected to the enable terminal of the electric tool, and the second input terminal is connected to the first capacitor, so as to turn on the first controllable switch after the first capacitor is charged or when the enable terminal is at a first level, and turn off the first controllable switch when the first capacitor is not charged and the enable terminal is at a second level, and the second level is different from the first level; The capacitor control circuit includes a first terminal, a second terminal and a third terminal, wherein the first terminal is connected to the auxiliary switch, the second terminal is connected to the battery pack, and the third terminal is connected to the first capacitor, so as to charge the first capacitor through the battery pack after the auxiliary switch is closed, and discharge the first capacitor after the auxiliary switch is opened; The main switch is arranged between the battery pack and the motor drive circuit of the power tool, the first end and the second end of the first controllable switch are connected to the battery pack and the power supply end of the power tool respectively, and the switching state of the auxiliary switch is consistent with the switching state of the main switch.

2. The trigger circuit according to claim 1, characterized in that: The capacitor control circuit includes a second controllable switch, a first resistor, a second resistor and a capacitor discharge circuit; The first end of the second controllable switch is connected to the first end of the battery pack and the first end of the first resistor respectively, the second end of the second controllable switch is connected to the first end of the first capacitor, and the control end of the second controllable switch is connected to the second end of the first resistor and the first end of the second resistor respectively; The second end of the second resistor is connected to the first end of the auxiliary switch, and the second end of the auxiliary switch is grounded; the first end of the first capacitor is connected to the capacitor discharge circuit.

3. The trigger circuit according to claim 2, characterized in that: The capacitor control circuit also includes a charging current limiting circuit arranged between the first end of the first capacitor and the second end of the second controllable switch.

4. The trigger circuit according to claim 3, characterized in that: The charging current limiting circuit is a third resistor.

5. The trigger circuit according to claim 2, characterized in that: The capacitor discharge circuit is a fourth resistor, a first end of the fourth resistor is connected to a first end of the first capacitor, and a second end of the fourth resistor is grounded.

6. The trigger circuit according to claim 2, characterized in that: The switch control circuit includes a third controllable switch, a fifth resistor, a sixth resistor and a seventh resistor; The control end of the third controllable switch is connected to the enable end of the electric tool and the first end of the fifth resistor, the first end of the third controllable switch is connected to the second end of the fifth resistor and the common end of the connection is grounded, the second end of the third controllable switch is connected to the first end of the seventh resistor, the second end of the seventh resistor is connected to the first end of the sixth resistor and the control end of the first controllable switch, and the second end of the sixth resistor is connected to the first end of the first controllable switch.

7. The trigger circuit according to claim 6, characterized in that: The switch control circuit further includes an eighth resistor, which is arranged between the enable terminal of the electric tool and the control terminal of the third controllable switch.

8. The trigger circuit according to claim 6, characterized in that: The first controllable switch is a PNP transistor, the second controllable switch is a PMOS, and the third controllable switch is an NPN transistor; The emitter of the PNP transistor serves as the first end of the first controllable switch, the collector of the PNP transistor serves as the second end of the first controllable switch, and the base of the PNP transistor serves as the control end of the first controllable switch; The emitter of the NPN transistor serves as the first end of the third controllable switch, the collector of the NPN transistor serves as the second end of the third controllable switch, and the base of the NPN transistor serves as the control end of the third controllable switch; The gate of the PMOS serves as a control terminal of the second controllable switch, the source of the PMOS serves as a first terminal of the second controllable switch, and the drain of the PMOS serves as a second terminal of the second controllable switch.

9. The trigger circuit according to any one of claims 1 to 8, characterized in that: A second capacitor is also included, the common end of the main switch connected to the motor drive circuit is connected to the first end of the second capacitor, and the second end of the second capacitor is grounded.

10. An electric tool, characterized in that: Comprising a trigger circuit as claimed in any one of claims 1 to 9.

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