Fan for protecting human body

Abstract

The invention discloses an electric fan for protecting human bodies, which comprises a circuit unit, a fan motor and an inductor. The circuit unit comprises a capacitance detection module used for detecting the ground capacitance of the inductor, an environment compensation module used for calculating the average value of the ground capacitance of the inductor, a comparing control module used for comparing the ground capacitance of the inductor detected by the capacitance detection module and the average value of the ground capacitance of the inductor calculated by the environment compensation module and controlling the output of stop and turn signals, and a brake switch used for braking the fan motor by comparing standstill signals output by a control module. When a human body gets close to or touches the inductor, a deviation of the capacitance between the inductor and the ground from environmental capacitance is detected by the circuit unit. When exceeding the inner set value, the deviation indicates that the human body is close to or touching the fan, and then the circuit unit outputs signals to stop the fan motor from running immediately, thus fulfilling the protecting function.

Description

Technical field [0001] The invention relates to a human body protection electric fan, and particularly relates to a human body protection electric fan that stops rotating immediately when the human body approaches or touches, and prevents high-speed rotating fan blades from causing harm to the human body. technical background [0002] In the prior art, the human body protection electric fan has the following implementation forms: one is through the principle of the human body's own capacitance. When the human body touches the grille, the human body's own capacitance causes the input voltage to deviate from the set reference, and the information is transmitted to the control system to control the fan motor to stop immediately to prevent the high-speed rotating fan from causing harm to the human body. This design has two major shortcomings: First, the reference is fixed compared with the human input signal, which is susceptible to malfunction due to external interference. For examp...

AI Technical Summary

Problems solved by technology

This design has two major disadvantages: First, the benchmark for comparison with the human input signal is fixed, and it is susceptible to malfunctions caused by external interference, such as changes in air temperature and dirt on the grille. The second is to rely on the human body to touch the fan to realize the function, which may cause the protection to be delayed and still cause personal injury

This scheme deficiency has: the one, adopts the oscillating circuit to detect the human body capacitance, is not suitable for being used in the environment that electromagnetic change is arranged, particularly the very strong AC electric fan of AC electromagnetic field; Summarize the number of pulses, although this method can eliminate certain errors, it may also accumulate errors

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