Patent ID: 8037947
Filing Date: 2011-10-18
Classification: B25D

Abstract:
1. An impact tool comprising: a cylindrical housing having a bit-installable end; a cylinder provided in a rear space within the housing, the cylinder incorporating a motor-driven reciprocating piston and an impactor that is provided frontward of the piston and configured to be moved in synchronization with the piston; an interjacent element provided within the housing between the cylinder and a bit, and configured to be movable rearward and frontward in a predetermined stroke and to be pressed rearward into a retreated position by a rear end of a bit when the bit is installed, wherein the impactor reciprocating in synchronization with the piston is configured to strike the interjacent element so that the bit is indirectly struck; a shock-absorbing element disposed frontward of the interjacent element within the housing; a washer disposed rearward of the shock-absorbing element and adjacent to the shock-absorbing element, wherein the interjacent element is configured to come in contact with the washer when the interjacent element is caused to advance by the impactor's strike under no-load conditions, the no-load conditions comprising at least a condition where the impact tool is withdrawn from contact with a workpiece; a sleeve disposed rearward of the washer, and adjacent to the washer, wherein the sleeve is configured to position the shock-absorbing element and the washer in place, and to allow the interjacent element to move rearward and frontward inside the sleeve; and a second shock-absorbing element disposed between the sleeve and the cylinder such that the impactor advancing under the no-load conditions strikes the second shock-absorbing element, wherein the second shock-absorbing element is configured to position a rear end of the sleeve indirectly with respect to the impactor.