The inner structure of a drill

The internal structure of a drill consists of the three main parts motor, gear and drill head or drill chuck. Depending on the variety of functions, there are also several setting and operating switches and levers. The gun-like housing allows the user to exercise the necessary counterforce.

Housing and operating switch

The handle of a drill always forms an angle between 45 and 90 degrees to the direction of rotation of the rotating drilling axis. In this way, the rotational forces can be controlled with muscle power when operating the drill. The power supply and the power supply that downshifts the operating voltage for the motor are placed in the handle.

The power switch is mounted as a "trigger" or "trigger" in the bend between the handle and center housing at the bottom of the drill. A locking button is located across the trigger and locks the pulled and thus activated trigger. If present, there is a speed control on the bottom of the trigger.

function switch

The available function switches are mounted on top of the housing above the engine or transmission. A directional switch triggers left and right rotation of the motor. If a hammer drill function can be activated, a slide switch is placed in the front third of the top of the housing. Also, a possible gear shift is set in this area.


The heart of the drill is the motor that delivers between 500 and 2000 watts of power for home improvement needs. The motor placed in the middle of the housing has so-called coals on the back towards the handle. They form the required sliding contact, which "brings" the rotational force out of the motor. Changing the components also called carbon brushes is possible.

Gearbox and bearings

The output shaft of the engine leads via a staggered gearbox to the drilling shaft in the pivot bearing. Depending on the equipment here is selected by off or off gear offset impact and set the torque.

Drilling head or chuck

Depending on the type of drill chuck, the drill head is plugged or screwed onto the drilling shaft protruding from the bearing. On machines with adjustable clockwise and anti-clockwise rotation, a locking screw must fix the drill chuck on the drilling shaft.

Tips & Tricks

The construction of drills allows you to use the machine in both horizontal and vertical orientation. Clamping in a drill stand is easily possible.

Video Board: Inside a Drill +