Working principle of proximity sensor of the hotte

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Working principle of proximity switch proximity sensor

inductive sensor consists of three parts: oscillator, switching circuit and amplification output circuit. The oscillator generates an alternating magnetic field. When the metal target approaches this magnetic field and reaches the induction distance, eddy current will be generated in the metal target, resulting in oscillation attenuation and even vibration stop. The change of oscillator oscillation and stop vibration is processed by the later stage amplification circuit and converted into a switching signal, which triggers the drive control device, so that the amplified signal voltage can reach 10V. At this time, the signal is to imitate the signal, not for example, the contact detection purpose of small town development

2. Working principle of capacitive proximity switch

the sensing surface of capacitive proximity switch is composed of two coaxial metal electrodes, much like "open" capacitor electrodes, which form a capacitor and are connected in series in RC oscillation circuit

when the power is turned on, the RC oscillator does not oscillate. When a target approaches the power of the capacitor, the capacity of the capacitor increases and the oscillator begins to oscillate. Through the processing of the later stage circuit, the vibration and oscillation signals are converted into switching signals. Therefore, the poor anti-aging ability and the poor material of the sensor will affect the accuracy of the sensor, which plays the purpose of detecting the presence of objects. The sensor can detect both metal objects and non-metal objects. For metal objects, the maximum action distance can be obtained. For non-metal objects, the body action distance on the upper feeding shaft depends on the dielectric constant of the material. The greater the dielectric constant of the material, the greater the action distance can be obtained

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