A power tool (10, 40) comprising: a tool accessory; a motor (13, 43) configured to drive the tool accessory; a control module (21, 51, 61) configured to control the motor (13, 43); a power supply module (18, 54, 64) configured to provide electric power for the motor (13, 43) and the control module (21, 51, 61); and an operating switch (16, 46), comprising: a trigger mechanism (161, 461); a current switch (SW1, SWI') for turning on or off the electrical connection between the power supply module (18, 54, 64) and the motor (13, 43); the current switch (SW1, SWI') being coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461); and a signal switch at least configured to output a control signal to the control module (21, 51, 61) to control the start of the motor (13, 43); the signal switch being arranged to connect with the trigger mechanism (161, 461) and to be actuated by the trigger mechanism (161, 461), characterized in that the signal switch comprises: a first signal switch (SW2') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output a signal to the control module (21, 51, 61) to brake the motor (13, 43); and a second signal switch (SW3') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output the signal to the control module (21, 51, 61) to start the motor (13, 43). a tool accessory; a motor (13, 43) configured to drive the tool accessory; a control module (21, 51, 61) configured to control the motor (13, 43); a power supply module (18, 54, 64) configured to provide electric power for the motor (13, 43) and the control module (21, 51, 61); and an operating switch (16, 46), comprising: a trigger mechanism (161, 461); a current switch (SW1, SWI') for turning on or off the electrical connection between the power supply module (18, 54, 64) and the motor (13, 43); the current switch (SW1, SWI') being coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461); and a signal switch at least configured to output a control signal to the control module (21, 51, 61) to control the start of the motor (13, 43); the signal switch being arranged to connect with the trigger mechanism (161, 461) and to be actuated by the trigger mechanism (161, 461), characterized in that the signal switch comprises: a first signal switch (SW2') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output a signal to the control module (21, 51, 61) to brake the motor (13, 43); and a second signal switch (SW3') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output the signal to the control module (21, 51, 61) to start the motor (13, 43). a trigger mechanism (161, 461); a current switch (SW1, SWI') for turning on or off the electrical connection between the power supply module (18, 54, 64) and the motor (13, 43); the current switch (SW1, SWI') being coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461); and a signal switch at least configured to output a control signal to the control module (21, 51, 61) to control the start of the motor (13, 43); the signal switch being arranged to connect with the trigger mechanism (161, 461) and to be actuated by the trigger mechanism (161, 461), characterized in that the signal switch comprises: a first signal switch (SW2') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output a signal to the control module (21, 51, 61) to brake the motor (13, 43); and a second signal switch (SW3') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output the signal to the control module (21, 51, 61) to start the motor (13, 43). a first signal switch (SW2') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output a signal to the control module (21, 51, 61) to brake the motor (13, 43); and a second signal switch (SW3') coupled to the trigger mechanism (161, 461) to be actuated by the trigger mechanism (161, 461) and configured to output the signal to the control module (21, 51, 61) to start the motor (13, 43).