Calibration testing apparatus for medicinal powder aerosol concentration sensor

Abstract

The invention discloses a calibration testing apparatus for a medicinal powder aerosol concentration sensor. The calibration testing apparatus comprises a medicinal powder atomization and homogenization cavity, a sensor testing unit, a control and display unit, a splitting plate and a guide plate, wherein the splitting plate and the guide plate are used for adjusting air flow; the control and display unit is used for setting, acquiring, displaying, adjusting and controlling parameters like flow velocity and pressure intensity of air flow in the apparatus, carrying out data operation and realizing cleaning of the apparatus; the medicinal powder atomization and homogenization cavity is used for accomplishing atomization of medicinal powder and rapid uniform mixing of medicinal powder aerosol; the state of medicinal powder aerosol in an output pipeline of a medical atomizer is simulated by using the sensor testing unit; and with the concentration, flow velocity and pressure intensity of the medicinal powder aerosol as variables, a to-be-calibrated sensor is calibrated. The standard medicinal powder aerosol prepared in the invention has good uniformity and stability, can be used for calibration testing of a plurality of influencing parameters of the to-be-calibrated sensor and improves accuracy of calibration of the medicinal powder aerosol concentration sensor.

Description

technical field [0001] The invention relates to a calibration test device for a concentration sensor, in particular to a calibration test device specially used for a concentration sensor of a drug powder aerosol, and belongs to the technical field of medical instruments. Background technique [0002] Nebulization inhalation therapy uses a medical nebulizer to disperse the drug (solution or powder) into tiny mist or particles, suspend it in the gas, and enter the respiratory tract and lungs for deposition, so as to moisten the respiratory mucosa, reduce inflammation and eliminate phlegm, For the treatment purpose of relieving spasm and relieving asthma, this treatment method can be applied to the treatment of various acute and chronic inflammations of the respiratory tract and the treatment of asthma and other diseases. Huge advantage. In aerosol inhalation therapy, it is usually necessary to change the dosage of the drug at any time as needed and adjust the concentration of...

AI Technical Summary

Problems solved by technology

Representatively: Chinese invention patent (CN104359724 A) discloses a polydisperse calibration system for airflow unidirectional flow type particle equipment, which mainly includes a zero air generator, a particle generator, a residence chamber and a calibration instrument connected in sequence by a conduit, It can be checked online whether the measurement value of the sampling instrument meets the standard. If the measurement of the instrument is found to be non-standard, it can be re-calibrated according to the polydisperse calibration system of the particle equipment, so as to improve the accuracy of sampling. However, this calibration device needs to be continuously fed. The uniformity and stability of the aerosol concentration are difficult to guarantee, and it is easy to cause waste of experimental materials; Chinese invention patent (CN102590447 A) and Chinese invention patent (CN102830047 A) respectively disclose a circulating dust calibration device, wherein, The patent (CN102830047 A) discloses a circulating dust generating device, which includes a cavity and an axial fan. There are openings on the top and bottom of the cavity. The other end is connected to the opening at the top of the cavity through a circulation pipe, which can realize dust reuse, and the dust environment in the dust generating device is more stable; the patent (CN102590447 A) relates to a calibration method and equipment for a dust measuring instrument, including Dust measuring instrument, self-circulating pipeline, dust generating device, flow measuring device, flow rate and pressure regulating valve, circulating fan, air filter, air heater, switching valve, dust collector, exhaust fan and connecting pipes between various equipment, etc. , the weighed test dust is dispersed and sent to the self-circulation system with stable gas flow, so as to produce a standard dust-containing gas with a flowing and stable concentration, so that the calibrated dust meter can be calibrated quickly and accurately; Patent (CN201622229 U) discloses a comprehensive calibration test bench for dust detection transmitter, which consists of a dust density ratio unit, a dust detection transmitter receiving unit, a dust density detection unit, a dust detection transmitter emission unit, and a temperature heating unit , observation window and sensor installation unit, high-speed high-pressure fan output interface unit, high-speed high-pressure fan, high-speed high-pressure fan input interface unit, test bench frame, etc., using the specified dust ratio in a closed-loop pipeline with a standard volume to simulate the atmosphere Moderate dust density conditions, used to test the output data of the dust detection transmitter under different dust density conditions, as well as data such as sensitivity, accuracy and reliability

[0004] Regarding the working principle of medical nebulizers, the circulating calibration devices introduced by the above three patents have common problems: (1) The entire air circulation channel is approximately square after assembly, without consideration of high-speed fans, sudden changes in pipe cross-section, and pipe direction Sudden changes in the air circulation channel and the interference caused by factors such as pillars and valves in the air circulation channel will easily cause spiral flow, air separation and strong turbulent flow, and dust deposition will occur. The air flow velocity and pressure stability in the calibration device are poor. The calibration results caused a large error; (2) The aerosol of medical powder output by the medical nebulizer has the characteristics of low flow rate and low concentration, and the flow rate has a great influence on the detection signal when the aerosol concentration is measured by the electrostatic method. The calibration of the above three patents In order to ensure the uniform flow of the aerosol, the wind speed in the air circulation channel is relatively high, and if the wind speed is set to a small value, it is easy to cause the sedimentation of the particles under the action of gravity. There are obvious limitations in internal circulation, which is not conducive to the repeatability and reliability of sensor calibration; (3) It is difficult to measure the influence of pressure and flow rate changes on the output signal of the powder aerosol concentration sensor, and cannot be used for a comprehensive evaluation of sensor performance

[0005] After comparative consideration, the existing dust calibration device cannot simulate the aerosol environment in the output pipeline of the medical nebulizer well, and is not suitable for calibrating the aerosol concentration sensor of the drug powder

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