DIY Knowledge

Rotary hammer


Martillo perforador


A rotary hammer is a power tool with a rotating machine tool for drilling in masonry, concrete, artificial and natural stone. It is equipped with a percussive hammer mechanism. The striking energy is independent of operator pressure.

If the hammer mechanism can be turned off, the rotary hammer can be used like a drill, if the rotation mechanism can be turned off, it turns into a percussion hammer. Tool speed and impact force can be adjusted electronically to match the processed material.

Rotary hammers are divided up by weight into these categories:

Light rotary hammers weigh from 1.8 to 3.0 kg, medium hammers from 4 to 5 kg, and heavy hammers from 6 to 12 kg.

The universal motor powers an electro-pneumatic, low-vibration hammer mechanism which in turn is energised by an enclosed, pressurised and elastic air-cushion which ensures that the impact force remains constant. Light rotary hammers owe their low-vibration and noise reduced running to a flywheel transducer and a slipper piston. Medium and heavy rotary hammers utilise a conventional crank drive. Light rotary hammers of the latest generation are equipped with electro-mechanical striking mechanisms. In general, rotary hammers are used in their combined rotation/hammer function. Rotation can be switched off for slot-cutting or chiseling applications, or it is switched off automatically by the special shape of the chisel shank. This is called rotation stop.

The hammer mechanism can be turned off for the rotation-only mode which is required for drilling in steel, wood or plastic. This is called hammer stop.
(See also: cordless rotary hammers)