Pullout protection device

Abstract

The invention provides a power-unplugging protection device for household appliances, comprising: a zero-crossing detection circuit connected to an AC power supply, outputting a first signal when there is AC input, and outputting a second signal when there is no AC input; The control circuit is connected to the zero-crossing detection circuit, receives the output signal of the zero-crossing detection circuit, sends the first driving signal to the driving circuit when receiving the first signal, and sends the second driving signal to the driving circuit when receiving the second signal. Drive signal; specified load, the specified load is connected to the AC power supply through the relay; the drive circuit is connected to the relay, and when the second drive signal is received, the relay is controlled to be turned on; otherwise, the relay is controlled to be turned off broken. Through the technical solution of the invention, the personal safety of the user can be guaranteed, and the electric shock can be avoided when the user pulls out the plug of the household appliance. At the same time, because the specified load is used, no additional device is needed, which saves the cost.

Description

technical field [0001] The invention relates to the technical field of home appliances, in particular to a power-unplugging protection device. Background technique [0002] The diversity of household appliances can almost replace the previous cooking methods and bring users a good experience. With the development of electronic technology, the power supply scheme of household appliances on the market generally adopts the switching power supply scheme. [0003] With the popularity of household appliances, the safety of household appliances has also been raised to an unprecedented height. Because in the domestic market, ordinary users have the habit of pulling out the plug after using household appliances, and when the plug of many household appliances is pulled out, the voltage between the live wire and the neutral wire at both ends of the plug has not undergone special treatment, resulting in the failure within 1s. Drop to the safe voltage of 36V, especially for household a...

AI Technical Summary

Problems solved by technology

[0009] The first way: Modify the resistor on the filter board, but this will increase the standby power consumption, which does not meet the safety requirements

[0010] The second way: Modify the capacitor on the filter board, but modifying the capacitor will cause all the EMC tests to be done again, and may involve changes in other parameters of the filter board, the cycle is long, and it is not conducive to standardization

[0011] The third method: add a relay control before the X capacitor on the filter board, so that the electrical connection is complicated, and an additional relay control is required, which increases the cost

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