US Patent 11607798 Hammer tool

A hammer tool includes a hammer head and a handle. The hammer head includes an insertion hole and first and second side holes aligned with each other and located on two opposite sides of and intercommunicating with the insertion hole. The handle includes an insertion portion on an end thereof. The insertion portion is inserted into the insertion hole. A first coupling flange is integrally formed with the insertion portion and is inserted into the first side hole. The handle includes a hollow portion extending in a longitudinal direction thereof. The handle further includes a third side hole extending in a radial direction thereof. An end of the third side hole intercommunicates with the hollow portion. Another end of the third side hole extends to an outer periphery of the insertion portion. The third side hole is aligned with the second side hole.