A Forward and Reverse Water Flow Sensor Based on Hall Switch

Abstract

The invention provides a forward and reverse water flow sensor based on a Hall switch in the field of intelligent water meters, comprising a sensor circuit, a data acquisition circuit and a power supply circuit; one end of the sensor circuit is connected to the data acquisition circuit, and the other end Connected with the power supply circuit; the data acquisition circuit includes a resistor R26, a resistor R27, a resistor R35, a resistor R36, a capacitor C13 and a capacitor C14; one end of the resistor R35 is connected to the sensor circuit, and the other end connected to the resistor R26 and the capacitor C13 respectively; one end of the resistor R36 is connected to the sensor circuit, and the other end is respectively connected to the resistor R27 and the capacitor C14; the capacitor C13 and the capacitor C14 are both grounded. The invention has the advantages of enhancing the ability of the sensor to resist ESD impact, and the Hall switch can be reset in time when the latch effect occurs.

Description

technical field [0001] The invention relates to the field of intelligent water meters, in particular to a forward and reverse water flow sensor based on a Hall switch. Background technique [0002] In the smart water meter industry, the existing water meter flow acquisition sensors mainly include the following types: [0003] One is the magnetic water meter sensor. The magnetic water meter sensor needs to install a magnetic flow pointer in the water meter body. The flow collection equipment integrates magnetic sensitive elements to detect the flow collection of the water meter. Since the magnetic pointer is installed in the water meter body, the metal water meter body There is an attractive effect, which increases the rotational resistance of the pointer and affects the performance of the water meter. [0004] The second is the camera direct reading water meter. The camera direct reading water meter takes pictures of the readings of the dial through the camera and uploads t...

AI Technical Summary

Problems solved by technology

[0003] One is the magnetic water meter sensor. The magnetic water meter sensor needs to install a magnetic flow pointer in the water meter body. The flow collection equipment integrates magnetic sensitive elements to detect the flow collection of the water meter. Since the magnetic pointer is installed in the water meter body, the metal water meter body Has an attractive effect, which increases the resistance to rotation of the pointer and affects the performance of the water meter

[0004] The second is the camera direct reading water meter. The camera direct reading water meter takes pictures of the readings of the dial through the camera and uploads them to the background for background software identification or manual identification. However, the use of camera direct reading water meters has the following defects: the amount of image data Too large, network transmission is difficult; high cost, difficult to promote; camera power is high, cannot support real-time monitoring, can only replace manual reading of water meter dial numbers regularly, and cannot monitor the flow process of water meters in real time

However, the LC metal induction sensor has the following defects: since the resonant waveform amplitude of the LC is affected by the metal sheet pointer approaching the LC resonant circuit, the distance between the metal sheet pointer and the LC resonant circuit is required to be relatively close, which makes the requirements for the structure of the water meter more complex. Harsh, can only be aimed at specialized water meter bodies, therefore, the versatility is poor

However, there are the following defects: high power consumption, because the application environment is relatively complex, there is interference from various external light sources, because the wet water meter is filled with water, which has a refraction effect on light and other factors, it is easy to cause the sequence of the two photosensitive electronic components to sense the light source The sequence changes; resulting in errors such as under-counting, over-counting, or inversion of forward and reverse flow collection counts

However, because the core device used by the magnetic sensor is the Hall switch, and the Hall switch has weak resistance to ESD, and because the extension line of the magnetic sensor is long and the circuit board of the magnetic sensor is small, even if the ESD protection device is added, When the magnetic sensor receives an ESD impact, it is difficult for the discharge circuit to release the pulse voltage, and it is easy to cause the Hall switch to have a latch-up effect and even be damaged

Images