Direct reading gauge

Abstract

The invention relates to a direct reading gauge, comprising a single-digit character wheel, an excitation device, and a stainless steel sheet pre-embedded in the center of the character wheel. A selection signal is lowered, and the excitation signal gives out an excitation, so that LC resonance is caused; as a steel sheet is shaped as an asymptotic line, when the character wheel rotates from 0 to 9, the excitation device and the steel sheet get closer and closer. If the steel sheet of the character wheel is far away from the excitation device, the oscillation from start to attenuation can last longer time; if the steel sheet is close to the excitation device, as the steel sheet absorbs energy of an inductor in the excitation device, the oscillation attenuates quickly, and therefore signals detected at the SELECT end at 0-9 positions of the character wheel are different; within a certain clock cycle after emission of the excitation, an AD (Analogue / Digital) converter is used for sampling the levels at the Select end, and the levels are averaged within each cycle. The amplitude scope (the amplitude scope includes ten sections, and each section represents the position of one digit) of the excitation device is judged according to the level amplitude, and then the position of the excitation device is judged, thus the accurate reading of the character wheel is obtained.

Description

(1) Technical field [0001] The invention belongs to the field of electrical instruments, in particular to a direct-reading meter. (2) Background technology [0002] The direct-reading table "directly reads" the number of the character wheel of the watch through encoding and decoding, which is compiled by the physical position of the digit on the character wheel. Most direct reading meters on the market use M-BUS communication. Take the transmissive photoelectric direct reading meter as an example: using the principle of photoelectric encoder, each character wheel is used as a code wheel, and five infrared receiving tubes sense the transparent position on the character wheel. The level changes caused by the infrared light emitted by the light slot form a group of five digits, which are decoded and transmitted to the system computer to display the same number as the value indicated on the meter window on the meter reading interface. The photoelectric direct-reading meter work...

AI Technical Summary

Problems solved by technology

This type of direct reading meter needs to be waterproofed in the sealing process, and the infrared light is easily affected by light and ambient humidity, resulting in unreliable readings

Therefore, the direct-reading meter has the following defects: when designing the circuit of the direct-reading meter, there are many components, the cost is large, and the circuit design is relatively complicated; in the application process, taking the water meter as an example, the direct-reading module can be directly application, but the direct reading module needs to be waterproofed (semi-liquid seal) when it is used in a wet water meter

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