Rotary hammer

This causes them to deliver a much more powerful hammer blow, making it possible to drill bigger holes much faster.

The majority of modern rotary hammers as well as all electric-powered chipping guns or jack-hammers all use this EP technology.

[4] Rotary hammer drills have an oil filled gearbox, which allows them to operate durably despite the large forces and shocks they receive and the grit-filled environments where they are often used.

Hilti has a technology called "ATC" or "Active Torque Control"[5] which works by disengaging the drive from the motor when the tool body begins to rotate excessively through the action of a secondary magnetic clutch in addition to the standard slip-clutch.

Apart from their main function of drilling concrete, the rotary action can be switched off and just the percussive force used.

Some bits use a full carbide "four-cutter" head with a geometry that makes jamming less common - even when rebar is present.

Hilti had the first "electro-pneumatic" rotary hammer on the market in 1967, the Hilti TE 17[7] The perforating devices differ, basically, depending on the intended use, which leads to the appropriate size, weight and impact force when applied:[8] Operation of perforating equipment is associated with much noise.