Electric drills can be divided into three categories: electric drills, impact drills, and hammer drills.
1. Electric drill: the power is the smallest, and the use range is limited to drilling wood and as an electric screwdriver. Some electric drills can be converted into special tools according to the use, and there are many uses and models.
2. Impact drill: The impact mechanism of impact drill is canine tooth type and ball type. The ball impact electric drill is composed of a moving disc, fixed plate, steel ball, etc. The moving disc is connected to the spindle through threads and has 12 steel balls; the fixed disk is fixed to the enclosure with pins and has 4 steel balls. Under the action of thrust, 12 steel balls roll along 4 steel balls, so that the cemented carbide bit has a rotating impact movement and can drill holes in brittle materials such as bricks, blocks and concrete. Off-overhead nails, so that the fixed disk rotates with the disc without impact, and can be used for ordinary electric drills.
3. Hammer drill (electric hammer): holes can be drilled on a variety of hard materials, with the widest range of use.
The prices of these three electric drills are arranged from low to high, and their functions have also increased. The selection needs to be combined with their respective scope of application and requirements.
