Hammer drill with a mode changeover mechanism

[0050] With reference to FIGS. 1 and 2 of the drawings, a hammer drill / driver constructed in accordance with the teachings of the present invention is generally indicated by reference numeral 10. As those skilled in the art will appreciate, the hammer drill driver 10 may be either a cord or cordless (battery operated) device and can have a housing 12, a motor assembly 14, a multi-speed transmission assembly 16, a clutch mechanism 18, a percussion or hammer mechanism 19, an output spindle assembly 20, a chuck 22, a trigger assembly 24 and a battery pack 26. Those skilled in the art will understand that several of the components of hammer drill / driver 10, such as the chuck 22, the trigger assembly 24 and the battery pack 26, are conventional in nature and need not be described in significant detail in this application.

[0051] Reference may be made to a variety of publications for a more complete understanding of the operation of the conventional features of hammer drill / driver 10.