Control method capable of slowing down transmit power attenuation of elevator light curtain

Abstract

The invention relates to a control method capable of slowing down transmit power attenuation of an elevator light curtain. The control method includes following specific steps that S1, an interlockingsignal of an elevator door is detected by a control circuit to determine whether or not the elevator door is closed for 2 seconds or above; S2, if the elevator door is closed for less than 2 seconds,the elevator light curtain works normally, if the elevator door is closed for greater than 2 seconds, the elevator light curtain stops working, and a power test unit on the control circuit performs testing on transmit power of each transmitting unit of the elevator light curtain one by one; S3, the smallest power value obtained by the testing is used as a calibration parameter; S4, based on the smallest transmit power calibration value of the control circuit, the optimal amplification factor of a receiving digital amplifier circuit is calculated to amplify an infrared receive signal. The control method automatically inspects the power of an infrared emitting tube in real time, and automatically adjusts the parameters of the receiving amplifier circuit according to the attenuation degree of the infrared emitting tube to greatly improve the life cycle of products.

Description

technical field [0001] The invention relates to the field of elevator light curtains, in particular to a control method capable of slowing down the emission power decay of the elevator light curtain. Background technique [0002] The infrared scanning detection device installed on the automatic door of the elevator is commonly known as the elevator light curtain, which is used to prevent the electric door from hitting and squeezing passengers during the closing process. After the elevator light curtain is installed and put into use, it is in a continuous working state 24 hours a day. The emission power of the infrared emission tube will attenuate with the prolongation of the use time, and the effective working distance will be shortened accordingly. When the effective working distance is reduced to less than the door opening width, the service life ends. Although the weak signal can be adapted by increasing the signal amplification of the receiving circuit, the signal is su...

AI Technical Summary

Problems solved by technology

Although the signal amplification factor of the receiving circuit can be increased to adapt to weak signals, but when the signal is super strong and the amplification factor is too high in the initial use, the signal will be distorted and the electromagnetic compatibility performance of the product will be greatly reduced.

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