A Hammer Drill, also know as Percussion Drill or Impact Drill, is a type of rotary power drill designed specifically for heavy-duty drilling into materials such as concrete, brick, wood, metal. Hammer Drills have a specially designed clutch that allows it to not only spin the drill bit but also to punch it in and out. The actual distance the bit travels in and out and the force of its blow are both very small but the hammering action is very rapid, thousands of BPM. Unlikely to SDS drills, hammer drills feature mechanical ratchet mechanism and use standard drill bits so can work with various type of materials. Hammer drills can operate in 2 modes, drill only or hammer and drill.
Hammer drills are typically used in many industries, including:
SDS Rotary Hammer Drills are similar to Hammer Drills in that they also pound the drill bit in and out while it's spinning. They use a piston mechanism instead of a special clutch enabling them to deliver a much more powerful hammer blow than traditional Hammer Drills - they are able to drill larger holes much faster.