The mechanical timer principle of electric fan is similar to that of mechanical clock, with ratchet. The ratchet in the watch is controlled by the hairspring, and the control of the timer is much simpler than that of the watch. The size of the distribution determines the length of the delay. The schematic diagram is as follows:

Mechanical timer is widely used in electrical appliances, hot air blower, beauty instrument, hairdressing instrument, health care instrument, electrical appliances, electric oven, microwave oven, electric timer, electric steamer and so on.

The electric fan timer is a humanized functional design from the perspective of users' actual needs. It takes into account our actual situation in the use process and gives a suitable scheme through further reference. For example, friends who are worried about sleeping and catching a cold can set the timing to facilitate the later effect experience.

Extended data

The main structure of mechanical timer:

1, power component

With the one-way mechanism of winding, manual rotation can only be tightened but not loosened. Tighten the spring to provide power for the whole system.

2. Release parts

A series of gears change speed, and when the spring is released, the number of rotation cycles is increased. At the end of the gear train, there are escapement wheels, escapement claws and hairspring to ensure the constant rotation speed of the gear train driven by the spring. The hairspring is equipped with a device for adjusting the length of the hairspring, so as to adjust the swing frequency of the escapement claw and ensure that the gear rotates at a set speed, so that the tightened spring will not be loosened at once and the speed will not be changed because of the tightness of the spring.

3, timing trigger device, make a gear in the gear train rotate to a certain angle and send out electrical or mechanical signals to stop power supply or ring.

The three parts work together to screw the timer to a certain scale, and actually do two things. One is to tighten the spring to provide the power to start the timer, and the other is to set the trigger position of the trigger mechanism by twisting the scale. Then, under the control of the escape wheel, the whole structure slowly releases the force of the spring, and the gears at all levels begin to rotate at a uniform speed until the trigger mechanism acts.

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