What are the common classifications of household electric drills

Electric drills can be divided into three categories: electric hand drills, impact drills, and hammer drills.

1. Hand drill: The power is the smallest, and the scope of use is limited to drilling wood and as an electric screwdriver. It does not have much practical value and is not recommended to buy.

2. Percussion drill: it can drill wood, iron and drill bricks, but cannot drill concrete. Some percussion drills indicate that concrete can be drilled, which is actually not feasible, but it is absolute for drilling tiles and concrete with a thin outer layer of bricks. No problem.

3. Hammer drill (electric hammer): can drill holes in any material, the most widely used.
The price of these three kinds of electric drills is arranged from low to high, and their functions are also increased. The specific selection needs to be combined with their respective application scope and requirements.

How to choose household electric drill correctly
1. Size selection of electric drill: with the increase of the size of electric drill, its price will also increase. The size of household electric drill is generally 20 mm.
2. Additional function selection of electric drill: for the same model, there will be some additional functions. For example, R in the model indicates that the drill can rotate forward and backward, and its advantage is that when the forward rotation fails, it can be converted to reverse; E in the model indicates that the electric drill can adjust speed, and it can be adjusted to low speed when high speed is not needed.
3. Use of electric drill: take the indoor ceiling as an example, the ceiling is made of reinforced concrete. If the impact drill is used to drill holes, it will take a lot of strength, but it will not happen when it is used to hit the wall. Therefore, the impact drill is suitable for daily use in the family, but for the drilling staff, the hammer drill should be preferred. The key is that the structure and working principle of the two are different. In the process of using the percussion drill, people need to constantly apply force to make it rotate. When using the percussion drill, just a little force at the beginning can make the drill move forward automatically.

4. Observe the outer packing of the drill. The outer packing of the tool should have clear pattern and no damage. The plastic box should be firm. The buckle of opening the plastic box should be firm and durable.
5. Observe the appearance of the drill. The appearance of the tool should be uniform in color. There should be no obvious shadow, dent, scratch or collision mark on the surface of the plastic parts. The assembly dislocation between the shell parts should be less than 0.5mm. The coating of the aluminum casting should be smooth and beautiful without defect. The surface of the whole machine should be free of oil and stain. When holding it by hand, the handle of the switch should be flat. The length of cable should not be less than 2m.
6. Check the name plate and instruction manual of the drill. The parameters of the name plate of the tool should be consistent with those on the 3C certificate. The detailed address and contact information of the manufacturer and manufacturer shall be provided in the instruction manual. Traceable batch number shall be provided on the nameplate or certificate.
7. Hold the drill by hand, turn on the power, operate the switch frequently by hand to make the tool start frequently, and observe whether the on-off function of the tool switch is reliable. At the same time, observe whether there are abnormal phenomena in the TV set and fluorescent lamp. In order to confirm whether the tool is equipped with an effective radio interference suppressor.
8. When the drill is powered on for one minute, hold it by hand during operation. The hand should not feel any abnormal vibration. Observe the commutation spark, and the commutation spark should not exceed grade. Generally, there should be no obvious arc light on the surface of the commutator from the air inlet of the tool. During operation, there should be no abnormal noise.

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