The essential difference between electric drill and electric hammer are:
　　(1) is not the same size.
　　(2), of course, is not the same weight. There is only an electric drill motor (stator and rotor +) gear bite and some revolutions, hammer is not the same, should be called the "hammer" so it has impact force, can drill concrete, stone hard material. So the volume ratio of a large hammer drill, electric hammer should be inside the cylinder, connecting rod, piston and other important parts. The electric drill can only drill wood, iron, plastic and other materials.


　　is the use of hammer piston, compressed gas impact drill bit, need not make much effort, can open 6--100mm in concrete, brick, stone and other hard materials on the hole in the hammer on the opening of materials of high efficiency, but it is not a hole in the metal. Electric drill is not impact, the need for human pressure on the metal, wood and other materials on the hole, the diameter of 6 - 50mm. advantage is small vibration, high precision hole, the price is not high. In addition, they are not the same as the drill bit, the former is the alloy with the drill, which is a common cutting bit. Hammer and hammer can open holes in concrete structures.


　　two is the movement of the piston, hammer for large diameter above 30MM. The utility model has the advantages of high efficiency, large aperture and long drilling depth. The disadvantage is that the vibration of the surrounding buildings have a certain degree of damage.


　　impact drill is suitable for about 25MM small diameter and short drilling depth. Such as the installation of expansion bolts. Very little damage to the surrounding structures.