Patent ID: 7647985
Filing Date: 2010-01-19
Classification: B25D

Abstract:
1. A hammer drill comprising: a tool bit having a longitudinal axis; a first driving mechanism part that linearly drives the tool bit along the longitudinal axis; a first clutch mechanism disposed in the first driving mechanism part and switchable between a power transmission state of transmitting a driving force and a power transmission interrupted state of interrupting the transmission of the driving force; a second driving mechanism part that rotationally drives the tool bit about the longitudinal axis; a second clutch mechanism disposed in the second driving mechanism part and switchable between a power transmission state of transmitting a driving force and a power transmission interrupted state of interrupting the transmission of the driving force; and a driving mode switching mechanism that switches the driving mode of the tool bit among a hammer mode in which the tool bit is caused to perform striking movement along the longitudinal axis, a drill mode in which the tool bit is caused to perform rotation about the longitudinal axis and a hammer drill mode in which the tool bit is caused to perform striking movement and rotation, wherein the driving mode switching mechanism includes: