Patent attributes
A shock attenuating coupling device is provided for a rotary impact tool for drivingly connecting a hammer mechanism to a drive anvil. The shock attenuating coupling device includes a first coupling member, a second coupling member, a drum, a shoe, and a body of resilient material. The first coupling member has a first drive portion. The second coupling member has a second drive portion. The drum is provided proximate the first drive portion and the second drive portion and has a radially inner engagement surface. The shoe is provided within the drum and between the first drive portion and the second drive portion. The shoe has a radially outer surface capable of being expanded in a radially outer direction. The body of resilient material is interposed between the drum and the shoe. The first drive portion and the second drive portion are configured to expand the shoe responsive to torsional displacement between the first coupling member and the second coupling member in order to compress the body of resilient material in engagement with the inner engagement surface of the drum.