Drilling Device
A drilling device capable of easily pulling an end bit out of a workpiece is provided. The drilling device is provided with a housing, a brushless motor, a motion translating mechanism, and an output portion. The motion translating mechanism includes a rotation transmitting portion. The rotation transmitting portion includes a bevel gear and clutch. The bevel gear has an abutment portion. The clutches has an abutted portion. Rotational play is formed between the abutment portion and the abutted portion.
1 . A drilling device comprising:
a housing;
a motor provided in the housing and rotatable in forward direction and reverse direction, the forward rotation and the reverse rotation being repeatedly performed in case of forward/reverse mode; and
a rotary motion transmitting portion configured to transmit a rotational force of the motor to an end bit, the rotary motion transmitting portion comprising:
a rotary member rotationally driven by the motor;
an abutment portion provided at the rotary member and rotatable together with the rotary member; and
an abutted portion rotationally driven upon abutment with the abutment portion during repetition of the forward rotation and the reverse rotation of the motor in the forward/reverse mode.
2 . The drilling device as claimed in claim 1 , wherein the abutment portion and the abutted portion are positioned away from each other in a circumferential direction of the rotary member in at least one of a first rotational direction of the rotary member when the motor is rotated in the forward direction and a second rotational direction of the rotary member when the motor is rotated in the reverse direction.
3 . The drilling device as claimed in claim 2 , wherein the rotary motion transmitting portion further comprises a deceleration portion configured to deceleratingly transmit rotation of the motor to the rotary member.
4 . The drilling device as claimed in claim 3 , further comprising a reciprocal motion translating portion configured to translate the rotational force of the motor into a reciprocal motion, and comprising:
a reciprocation member configured to impact the end bit; and
a cylinder accommodating therein the reciprocation member, the rotary member and the abutted portion being positioned radially outward of the cylinder;
wherein the abutted portion is movable in an axial direction of the cylinder, and is configured to transmit or shut-off the rotational force to the cylinder upon the axial movement.
5 . The drilling device as claimed in claim 4 , further comprising:
a trigger configured to turn on/off a power supply to the motor;
a switch configured to change an operation mode to the forward /reverse mode; and
a change-over dial configured to selectively provide one of an impact mode, a rotation mode, and an impact/rotation mode, in the impact mode only an impacting force being transmitted to the end bit by the reciprocal motion translating portion, in the rotation mode only a rotational force being transmitted to the end bit by the rotary motion transmitting portion, and in the impact/rotation mode the impacting force and the rotational force being transmitted to the end bit;
wherein the motor is operated in the forward/reverse mode by manipulating the switch and pulling the trigger while the change-over dial is at the rotation mode.
6 . The drilling device as claimed in claim 4 , further comprising a change-over dial configured to selectively change an operation mode to one of an impact mode, a rotation mode, an impact/rotation mode, and a forward/reverse mode, in the impact mode only an impacting force being transmitted to the end bit by the reciprocal motion translating portion, in the rotation mode only a rotational force being transmitted to the end bit by the rotary motion transmitting portion, and in the impact/rotation mode the impacting force and the rotation force being transmitted to the end bit.
7 . The drilling device as claimed in claim 1 , wherein the housing includes a main body portion accommodating therein the motor and the rotary motion transmitting portion, and a handle portion movable relative to the main body portion; and the drilling device further comprising:
a detecting portion configured to detect movement of the handle portion; and
a controller configured to set the operation mode to the forward/reverse mode in accordance with a result of detection by the detecting portion.
8 . The drilling device as claimed in claim 7 , wherein the detecting portion comprises a load sensor.
9 . The drilling device as claimed in claim 7 , wherein the detecting portion comprises a position sensor.
10 . The drilling device as claimed in claim 1 , wherein the motor is a brushless motor.