Patent ID: 8087474

Claim:
A hammer drill comprising: a tool holder provided in a housing and configured to be rotatable with a bit being attached to a front end of the tool holder; a motor having an output shaft, the motor being disposed rearward of the tool holder with the output shaft oriented in a direction perpendicular to an axis of the tool holder; an impact mechanism provided in the housing and configured to strike the bid according to a rotation of the output shaft; a reduction shaft disposed in a position parallel to the output shaft between the output shaft and the tool holder, the reduction shaft comprising a driven gear and a bevel gear, the driven gear being configured to mesh with the output shaft, and the bevel gear being configured to couple with the tool holder, so that a rotary motion of the output shaft is transmitted to the tool holder; a clutch pin provided in the reduction shaft and slidable along an axis of the reduction shaft, the clutch pin being configured to be slidable by an operation from outside the housing; and a clutch mechanism configured to select between a hammer drill mode where the driven gear is caused to engage with the reduction shaft so that a rotary motion is transmitted to the tool holder and a hammer mode where the driven gear and the reduction gear are disengaged from each other so that the rotary motion transmitted to the tool holder is interrupted, the driven gear being configured to be rotatable separately from the reduction shaft, and the engagement between the driven gear and the reduction shaft and the disengagement between the driven gear and the reduction shaft being switchable in accordance with sliding positions of the clutch pin; wherein the clutch pin is configured to be slidable to a sliding position where the clutch pin runs through the reduction shaft so as to be capable of protruding upward beyond the reduction shaft, and at the sliding position, the clutch pin engages with an engagement portion provided on the tool holder side so that a rotation of the tool holder can be locked, whereby in the hammer mode, a selection can be further made between a neutral state where the clutch pin does not engage with the engagement portion to allow free rotation of the tool holder and a rotation locked state where the clutch pin engages with the engagement portion to lock the rotation of the tool holder.