To minimize vibration generated by the operation of a hammer drill.
This hammer drill includes: a body 2 having a motor; a tool holder 6 holding a tool bit; a hammer mechanism driven by the motor to repeatedly hammer the end of the tool bit; counter masses 20, 50 fitted in the body 2 to slide and slid forward and backward between two end parts; and energizing means 22, 24, 32, 34, 62 for energizing the counter masses 20, 50 to a third position disposed between the first and second positions so that the counter masses are disposed on the center of gravity 9 of the hammer in the third position, and the masses of the counter masses 20, 50 and the strengths of the energizing means 22, 24, 32, 62 are moved to cause the counter masses 20, 50 to slide forward and backward, thereby performing extinction of vibration generated by the operation of the hammer mechanism.
JPS57211482A | 1982-12-25 | |||
JP2004154903A | 2004-06-03 | |||
JP2004345001A | 2004-12-09 | |||
JP2004299036A | 2004-10-28 | |||
JP2003011073A | 2003-01-15 | |||
JP2004216524A | 2004-08-05 | |||
JPS52109673A | 1977-09-14 | |||
JPS63210425A | 1988-09-01 | |||
JP2004162905A | 2004-06-10 | |||
JPS57211482A | 1982-12-25 | |||
JP2004154903A | 2004-06-03 | |||
JP2004345001A | 2004-12-09 | |||
JP2004299036A | 2004-10-28 | |||
JP2003011073A | 2003-01-15 |
Jun Tsuruta
Tetsuro Shimada
Yoryo Mihashi