Patent ID: 11938605
Assignee: NANJING CHERVON INDUSTRY CO., LTD.
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. An electric tool, comprising:
a housing;
a motor disposed in the housing;
a tool interface configured to connect to a power supply to the motor;
a control system comprising a control circuit and configured to control a rotation of the motor; and
a master switch disposed on a current path formed by the tool interface and the control system;
wherein the master switch has an on state in which electric connection between the tool interface and the control circuit is in an off state in which the electric connection between the tool interface and the control circuit is off, the control system comprises a protection circuit connected between the master switch and the control circuit, and the protection circuit is configured to disconnect connection between the tool interface and the control circuit in response to the master switch being in the on state before the tool interface connects to the power supply,
wherein the protection circuit comprises a first power supply branch, the first power supply branch comprises a capacitor electrically connected to the master switch, and the capacitor is not powered on in response to the master switch being in the on state before the tool interface connects to the power supply,
wherein the capacitor is powered on in response to the master switch being in the off state after the tool interface connects to the power supply and the capacitor is configured to discharge in response to the master switch being in the on state after the tool interface connects to the power supply, and
wherein the first power supply branch further comprises a first triode, at least one end of the first triode is connected to the capacitor, and the first triode is configured to turn on in response to the capacitor discharging.