Every craftsman, handyman and craftsman has used them – the drilling machine. There are many types of drilling machines, we look more closely at the electric hand drill. It is a practical and versatile tool when it comes to drilling a hole in different materials. Be it wood, plastic or stone – the drilling machine allows to drill holes with different diameters and depths.
Casing
The externally visible part of the drilling machine is the housing. It is mostly made of plastic and is produced in half-shell construction. On the housing you will find manufacturers and usually a type plate with indication of the electrical power consumption, the number of revolutions, the operating voltage and the protection class. The mains cable for the electrical connection is removed from the housing. Many drilling machines still have an additional handle, which is attached to the housing. Such a drilling machine can be easily held with two hands.
Engine
The electric motor is the heart of every drilling machine. It generates the necessary rotary movement of the drill. Usually motors are operated with 220V alternating voltage, but there are also corded boring machines that can handle DC voltages below 20V.
Transmission
The high speed of the electric motor is not suitable for drilling, so the high speed of the motor is translated into a lower speed of the drill by means of a gearing. In this case, a gear transmission is used which is often designed as a manual transmission. This makes it easy to set at least 2 different gear ratios (“gears”) and sometimes even a “reverse”. This setting is made with the “gear switch”.
Chuck
This part of the drilling machine is an attachment which receives the drill and allows to work with different drills by exchanging them quickly. By turning the drill chuck key, the chuck jaws can be moved inside the chuck and the drill can be fixed or loosened again.
Drill
The drill (more precisely, the drilling tool) is the insert that is picked up by the drill chuck. It penetrates the material through the cutting edge at the tip. There are drills for different materials – for metal, stone, wood and plastic. In the commercially available hand drilling machines, spiral drills with a conical head are usually used.
A special type of hand drilling machine is the percussion drill. In this case, stroke movements with high frequency are performed by the (switchable) impact mechanism in addition to the rotary movement of the drill. They feel like a vibration during drilling and support the drilling process for materials such as concrete or stone.