1. Remove the toothbrush head first, then turn the bottom of the electric toothbrush, and the bottom cover will be pulled out.

2. Then take out the battery and pry open the buckle. If the buckle is not easy to pry open, you can pry open the buckle with tools, and then tap the top of the electric toothbrush a few times to take out the main core.

3. Remove the waterproof glue sleeve and pry out the switch. For example, in the video, some electric toothbrushes have buckles installed outside the motor, while others don't. After prying open the buckle, you can take out the motor.

4. Next, it can be repaired according to the fault of the electric toothbrush.

Comprehensive inspection, disassembly and maintenance methods of electric toothbrush faults.

1. Disassembly of electric toothbrush motor assembly:

Pull out the brush head as shown in the figure, pull out the battery back cover as shown in the figure, and open the battery back cover. We can see that the motor is stuck in the groove of the inner hole of the handle through the plastic bracket. As long as one hand holds down the motor slot and the other hand pushes against the brush head, the whole motor is easy to fall off.

2. Dirt in the handle of the faulty toothbrush:

After removing the motor, you can see that different positions inside are dirty. Most of the dirt is formed around the motor sealing ring for many years, and the brush head and handle are also dirty.

3. Clean and check the outside of the motor.

Wipe the dirt on the motor with clean paper, and don't rinse it with water, because there is no water in the motor coil.

Then lever out the motor connector with a small screwdriver and finally lever out the sealing ring.

After disassembling the sealing ring, we found that there are two small holes on one side of the motor shell, which directly lead to the internal coil, but there is water, which means that the motor has been flooded, so the motor output shaft can't be moved by hand, and it can only be twisted by clamping it with needle-nosed pliers, which fully shows that the motor has been blocked and stuck.

4. Disassembly of motor fixing bracket and battery terminal:

Through careful observation, we found that the battery terminal is directly welded to the motor, but it is clamped by the motor bracket. We use a screwdriver to pry out the battery terminal as shown in the figure, and the motor bracket can be completely loosened.

5. Internal anatomical examination of the motor:

The motor is integrated. It seems that the motor can only be replaced after inspection. Can it be further overhauled?

We use needle-nosed pliers to break off the inclined parts of the four corners of the motor end cover. Then push the motor output shaft on the table, and the motor end cover will be pushed out.

6. Internal cleaning and lubrication of the motor.

After disassembling the motor rotor, we found that the inner copper sleeve around the output shaft end of the motor had rusted, which caused great motor resistance. We wipe the rotor conductive ring with cloth or paper to ensure good contact. It should be noted that there is a friction washer at the end of the conductive ring shaft, which must not be lost, otherwise the axial resistance will be too great.

7. Inspection of motor rotor coil:

Although it is unlikely that the motor with only 3V DC power supply will be disconnected, in order to avoid detours in maintenance, we still use a multimeter to detect the resistance of a coil and conductive ring. The conductive ring of the motor is divided into four poles, and the resistance between each two poles is about1.4Ω, indicating that there is no problem with the coil.

8. Add lubricating oil to the motor:

It can be seen from the inside of the disassembled motor that the motor uses food-grade white grease. If you can't find food grade lubricants, you can also choose very food-grade grease as a substitute. 9. Fixation of motor end cover of electric toothbrush:

After the motor end cover is installed in place, we must restore and fix the end cover. As shown in the figure, erect the motor, clamp the output bearing end of the motor in the oval hole of the vice, and tap the four clamping parts of the motor end cover with a screwdriver to press the motor end cover.

10. Electric toothbrush motor circuit inspection and power-on debugging:

When the motor end cover is installed and positioned, we need to test the path between the battery terminal and the motor, as shown in the figure. The resistance between the two poles of the battery was detected with a resistance file, and the measured resistance was about1.0-1.5 Ω, indicating that the motor was normal.

1 1. The real cause of motor failure of electric toothbrush is drainage blockage.

Why does the motor get water? Through the above disassembly, we found that a ***3 hydrophobic hole on the toothbrush handle and brush head was mainly caused by dirt blockage. We can dredge the hydrophobic holes with toothpicks as shown in the figure.