A Calibration Test Device for Medicated Powder Aerosol Concentration Sensor

Abstract

The invention discloses a calibration test device for a drug powder aerosol concentration sensor. The control and display unit is used for the setting, collection, display and adjustment control of parameters such as airflow velocity and pressure in the device, for data calculation processing and device cleaning; the uniform chamber for powder atomization is used to complete the rapid atomization of drug powder and aerosol of drug powder Mix evenly; use the sensor test unit to simulate the state of the powder aerosol in the output pipeline of the medical nebulizer, and use the concentration, flow rate and pressure of the powder aerosol as variables to calibrate the sensor to be calibrated. The standard medicament powder aerosol prepared by the invention has good uniformity and stability, can be used for calibration tests of various influencing parameters of the sensor to be calibrated, and improves the calibration accuracy of the medicament 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 (CN102590447A) and Chinese invention patent (CN102830047 A) respectively disclose a circulating dust calibration device, wherein the patent (CN102830047 A) discloses a dust generating device for circulating dust, which includes a cavity and an axial fan. There are openings on the top and bottom of the cavity. One 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 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. After the weighed test dust is dispersed, it is sent into a self-circulation system with a stable gas flow rate, thereby producing 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 proportioning unit, a dust detection transmitter receiving unit, a dust density detection unit, a dust detection transmitter emission unit, a temperature heating unit, The observation window and the sensor installation unit, the output interface unit of the high-speed high-pressure fan, the high-speed high-pressure fan, the input interface unit of the high-speed high-pressure fan, the test bench frame, etc., adopt the specified dust ratio in the closed-loop pipeline of the standard volume to simulate the dust in the atmosphere Dust density status, 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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