Electric work machine and driver drill
An electric work machine avoids use of more lead wires. The electric work machine includes an operation unit operable in an operation mode of at least three operation modes, an operable member movable to switch the operation mode, a plurality of mode sensors located in a direction of movement of the operable member to detect the operable member and being equal in number to or fewer than the at least three operation modes, a mode sensor board on which the plurality of mode sensors are mounted and including an output terminal connected to the plurality of mode sensors, and a controller board connected to the output terminal with an output lead wire to determine the operation mode based on an output signal output from the output terminal.
1 . A driver drill, comprising:
a motor;
an output unit driven by the motor;
a vibrator configured to vibrate the output unit in an axial direction;
a mode switch ring operable to change operation modes of the vibrator, the operation modes including a vibration mode and a non-vibration mode;
a reducer operable in a speed mode of at least three speed modes including a high-speed mode, a medium-speed mode, and a low-speed mode;
a speed switch lever movable to switch the speed mode of the reducer;
a plurality of mode sensors located in a direction of movement of the speed switch lever to detect the speed switch lever, the plurality of mode sensors being equal in number to or fewer than the at least three speed modes;
a mode sensor board on which the plurality of mode sensors are mounted, the mode sensor board including an output terminal connected to the plurality of mode sensors;
an operation unit configured to change a drive mode of the motor between a drill mode in which the motor is driven independently of a torque applied to the motor and a clutch mode in which the motor is stopped in response to torque applied to the motor exceeding a torque threshold;
a dial configured to change the torque threshold in the clutch mode; and
a controller board connected to the output terminal with an output lead wire to determine the speed mode based on an output signal output from the output terminal, the controller board configured to stop the motor in response to torque applied to the motor exceeding the torque threshold in the clutch mode based on detection signal from the mode sensors,
wherein
the torque thresholds are set to different values for an input value of the torque threshold in the high-speed mode, in the medium-speed mode, and the low-speed mode.
2 . The driver drill according to claim 1 , wherein
the plurality of mode sensors are fewer than the at least three speed modes by one.
3 . The driver drill according to claim 1 , wherein
each of a plurality of the output terminals is connected to a corresponding mode sensor of the plurality of mode sensors.
4 . The driver drill according to claim 3 , wherein
the mode sensor board includes an input terminal connected to the plurality of mode sensors, and
the plurality of mode sensors receive a voltage applied through the input terminal.
5 . The driver drill according to claim 4 , wherein
the plurality of mode sensors are connected in parallel with one another, and
each of the plurality of mode sensors is connected to the input terminal with a power line.
6 . The driver drill according to claim 5 , wherein
the mode sensor board includes the input terminal being a single input terminal.
7 . The driver drill according to claim 4 , wherein
the speed switch lever holds a permanent magnet,
each of the plurality of mode sensors includes a Hall sensor configured to detect the permanent magnet, and
each of the plurality of mode sensors includes
a power port to which a current is supplied,
a first ground port connected to the input terminal with a resistor in between, and
a second ground port connected to a ground.
8 . The driver drill according to claim 7 , wherein
the plurality of mode sensors include a first mode sensor and a second mode sensor,
the output terminal includes
a first output terminal connected to the first mode sensor, and
a second output terminal connected to the second mode sensor,
the resistor includes
a first resistor connected to the first mode sensor, and
a second resistor connected to the second mode sensor,
with the speed switch lever at a first position to switch the speed mode to a first speed mode, the first output terminal outputs an output signal at a first level, and the second output terminal outputs an output signal at a second level,
with the speed switch lever at a second position to switch the speed mode to a second speed mode, the first output terminal outputs an output signal at the second level, and the second output terminal outputs an output signal at the second level, and
with the speed switch lever at a third position to switch the speed mode to a third speed mode, the first output terminal outputs an output signal at the second level, and the second output terminal outputs an output signal at the first level.
9 . The driver drill according to claim 1 , wherein
the plurality of mode sensors are connected in parallel with one another, and
each of the plurality of mode sensors is connected to the output terminal with a signal line.
10 . A driver drill, comprising:
a motor;
an output unit driven by the motor;
a vibrator configured to vibrate the output unit in an axial direction;
a mode switch ring operable to change operation modes of the vibrator, the operation modes including a vibration mode and a non-vibration mode;
a reducer operable in a speed mode of a plurality of speed modes including a high-speed mode, a medium-speed mode, and a low-speed mode;
a speed switch lever movable to switch the speed mode of the reducer;
a plurality of mode sensors located in a direction of movement of the speed switch lever to detect the speed switch lever, the plurality of mode sensors being connected in parallel with one another;
a mode sensor board on which the plurality of mode sensors are mounted, the mode sensor board including an output terminal connected to the plurality of mode sensors;
an operation unit configured to change a drive mode of the motor between a drill mode in which the motor is driven independently of a torque applied to the motor and a clutch mode in which the motor is stopped in response to torque applied to the motor exceeding a torque threshold;
a dial configured to change the torque threshold in the clutch mode; and
a controller board connected to the output terminal with an output lead wire to determine the speed mode based on an output signal output from the output terminal, the controller board configured to stop the motor in response to torque applied to the motor exceeding the torque threshold in the clutch mode based on detection signal from the mode sensors,
wherein each of the plurality of mode sensors is connected to the output terminal with a signal line, and
the torque thresholds are set to different values for an input value of the torque threshold in the high-speed mode, in the medium-speed mode, and the low-speed mode.
11 . The driver drill according to claim 9 , wherein
the mode sensor board includes the output terminal being a single output terminal.
12 . The driver drill according to claim 9 , wherein
the mode sensor board includes an input terminal connected to the plurality of mode sensors, and
the plurality of mode sensors receive a voltage applied through the input terminal.
13 . The driver drill according to claim 12 , wherein
each of the plurality of mode sensors is connected to the input terminal with a power line.
14 . The driver drill according to claim 13 , wherein
the mode sensor board includes the input terminal being a single input terminal.
15 . The driver drill according to claim 12 , wherein
the speed switch lever holds a permanent magnet,
each of the plurality of mode sensors includes a Hall sensor configured to detect the permanent magnet, and
each of the plurality of mode sensors includes
a power port to which a current is supplied,
a first ground port connected to the input terminal with a resistor in between, and
a second ground port connected to a ground.
16 . The driver drill according to claim 15 , wherein
the plurality of mode sensors include a first mode sensor and a second mode sensor,
the resistor includes
a first resistor connected to the first mode sensor, and
a second resistor connected to the second mode sensor,
with the speed switch lever at a first position to switch the speed mode to a first speed mode, the output terminal outputs an output signal at a first level,
with the speed switch lever at a second position to switch the speed mode to a second speed mode, the output terminal outputs an output signal at a second level, and
with the speed switch lever at a third position to switch the speed mode to a third speed mode, the output terminal outputs an output signal at a voltage level resulting from voltage division with a resistance of the first resistor and a resistance of the second resistor.
17 . The driver drill according to claim 8 , wherein
the plurality of mode sensors are turned on to connect the first ground port and the second ground port in response to detecting the permanent magnet, and are turned off not to connect the ground port and the ground port in response to detecting no permanent magnet.
18 . The driver drill according to claim 17 , wherein
the first position is defined rearward from the second position,
the second position is defined rearward from the third position,
the first mode sensor is located to detect the permanent magnet with the speed switch lever at the first position, and located not to detect the permanent magnet with the speed switch lever at the second position or the third position, and
the second mode sensor is located to detect the permanent magnet with the speed switch lever at the third position, and located not to detect the permanent magnet with the speed switch lever at the first position or the second position.