Electric washing device is a small electric washer.
The continuous working time of the washer should not be too long, and each turn-on time shall not exceed 3-6s, and the two breaks should be more than 10s. The washer shall not be connected when there is no washing liquid in the storage tank. When using a scwasher, the wiper should be allowed to work at the same time. Turn on the washer first, and then turn on the wiper. The washing liquid should be kept clean to avoid blocking the nozzle.4. To regularly check and supplement the washing liquid. In winter, antifreeze additives should be added to avoid freezing and cracking liquid storage tank.11. Summarize the working principle of the two-speed permanent magnet motor.
Answer: Permanent magnet wiper motor uses 3 brushes to change the number of series coils between the positive and negative brushes to achieve speed change. The principle is: when the scraping motor works, the reverse potential is simultaneously generated in the armature, and its direction is opposite to the direction of the armature current. For the armature to rotate, the applied voltage must overcome the role of the antipotential. When the speed of the motor increases, the reverse potential increases, and the armature speed can stabilize only when the applied voltage equals the reverse potential (ignoring the armature voltage drop). When the wiper switch is pushed at a low speed, there are 4 series windings in each branch in the parallel circuit, and the size of the reverse potential is equal to that of the reverse potential in the branch. Because the applied voltage needs to balance the reverse potential generated by the four windings, the motor speed is low. When the switch is pushed to high speed, the series windings in two branches in the parallel circuit are not equal, one with five windings and one is three windings. Because the direction of the magnetic field inside the motor and the rotation direction of the armature do not change, the direction of the reverse potential within each winding is the same as at low speed. Two of the five windings have the opposite counterpotential direction. After canceling each other, each branch becomes three windings. The additional voltage only needs to balance the counterpotential generated by the three windings, so the actual effective voltage value at both ends of the armature winding increases, so the speed of the motor increases. When the motor speed increases and the reverse potential generated increases, the motor runs stably at a certain high speed.
