Patent 9815185 was granted and assigned to Makita on November, 2017 by the United States Patent and Trademark Office.
A hammer drill (101) comprises a main body (103) which houses a driving motor (110) and a driving mechanism and a handle (109) which is movable to the main body (103). Further, a coil spring (160) which biases the handle (109) is provided. In a state that the coil spring (160) biases the handle (109), the handle (109) is moved against the main body (103) in a longitudinal direction of a hammer bit (119) and vibration transmission from the main body (103) to the handle (109) is prevented.