Screening and detecting method for ultrasonic water flow detection transducers

Abstract

The invention discloses a screening and detecting method for ultrasonic water flow detection transducers. The screening and detecting method includes the following steps: 1), pre-checking piezoelectric ceramic elements and connecting electrode outgoing wires in a short circuit way; 2), putting the piezoelectric ceramic elements into a thermostat, simulating environment temperature and disconnecting two electrode outgoing wires; 3), assembling the ultrasonic water flow detection transducers; 4), checking the ultrasonic water flow detection transducers and connecting the electrode outgoing wires in a short circuit way; 5), putting the ultrasonic water flow detection transducers into the thermostat, simulating the environment temperature and then taking out the ultrasonic water flow detection transducers to be fixed; 6), performing load tests to the ultrasonic water flow detection transducers; and 7), performing appearance and electrical property tests to the ultrasonic water flow detection transducers. Compared with the prior art, the screening and detecting method has the advantages that cumulative stress of piezoelectric ceramic pieces can be released in advance; and the large stress generated due to strain during assembly of the piezoelectric ceramic pieces can be released to guarantee working stability and long-term operational reliability of the ultrasonic water flow detection transducers.

Description

technical field [0001] The invention belongs to the technical field of ultrasonic water meters, and in particular relates to a screening and detection method for ultrasonic water flow detection transducers. Background technique [0002] Ultrasonic water flow detection transducers are the key core components of ultrasonic water meters, ultrasonic flow meters, and ultrasonic heat meters. They usually use the time-of-flight measurement principle, so a pair of transducers are combined to work. Its technical performance indicators, working stability, adaptability to environmental influences (such as ambient temperature, humidity, vibration, etc.) Meter measurement accuracy and working stability. [0003] At present, due to the lack of detection and screening methods for ultrasonic water flow detection transducers, the long-term working characteristics of such transducers are in an uncontrolled and unpredictable state, which seriously affects the use quality and long-term reliabi...

AI Technical Summary

Problems solved by technology

[0003] At present, due to the lack of detection and screening methods for ultrasonic water flow detection transducers, the long-term working characteristics of such transducers are in an uncontrolled and unpredictable state, which seriously affects the use quality and long-term reliability of meter products. Sex: The piezoelectric ceramic element in the ultrasonic water flow detection transducer generates a large stress due to strain during the assembly process, and the piezoelectric ceramic element itself will also be due to cutting processing, high-voltage electrode Stress accumulated due to lead wire welding, etc. With the change of temperature and the continuation of time, these strains will be gradually released, resulting in obvious changes in the resonant frequency and acoustic-electric-electroacoustic conversion characteristics of the ultrasonic water flow detection transducer, which will affect the measurement. Measurement performance of meters

In addition, since the characteristic index of the piezoelectric ceramic element will decay over time, there is also the risk of the meter characteristic changing

Moreover, since the stress release and the attenuation process of the characteristic indicators of each piezoelectric ceramic element are different, the two piezoelectric ceramic elements installed in the same meter do not match after long-term use, which affects the performance of the meter. Working stability and long-term use reliability

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