Method for calibrating nonlinear proportional valve of respirator

Abstract

The invention discloses a method for calibrating a nonlinear proportional valve of a respirator. The method is achieved through a calibration unit on the respirator, after a proportional valve calibration mode is entered in, the closing effect of the proportional valve is detected first, if the proportional valve passes the detection, calibration is continued, then the calibration unit detects and records the minimum valve opening point voltage value Vmin and the maximum valve opening point voltage value Vmax of the proportional valve, a stepping value f is calculated and recorded, then the calibration unit drives the proportional valve by using the stepping valve f as steeping output drive voltages Vn, the flow values Qn flowing through the proportional valve under all driving voltages Vn are detected through a flow sensor, at last, the calibration unit generates a voltage-flow table according to detected data, the data in the voltage-flow table are fit to be n fitting straight lines to be stored, and calibration is achieved. According to the method, the voltage-flow curve of the nonlinear proportional valve is locally linearized, the voltage-flow relation of the nonlinear proportional valve can be well matched, the calculation process is simplified, and the accuracy of the calibration process is improved.

Description

Technical field [0001] The invention relates to the field of valve body calibration, in particular to a method for calibrating a non-linear proportional valve of a ventilator. Background technique [0002] A proportional valve is a pneumatic element whose output gas parameters change proportionally with the input electrical signal parameters. The gas parameters can be pressure, flow and direction, and the electrical signal parameters can be current or voltage. There are many types of proportional valves and they are widely used. [0003] In order to facilitate the use, the voltage-controlled proportional valve usually needs to verify the corresponding relationship between the voltage and the flow before use, so that the user can achieve precise control of the flow by controlling the voltage. The accuracy of the calibration of the proportional valve determines to a large extent whether the proportional valve can provide accurate gas flow for the ventilation circuit during the use o...

AI Technical Summary

Problems solved by technology

[0006] In order to overcome the defects that the existing proportional valve calibration method is difficult to meet the accurate calibration of the nonlinear proportional valve, and the calibration process is complicated and cumbersome, the technical problem to be solved by the present invention is to propose a calibration method for the nonlinear proportional valve of the ventilator. By partially linearizing the voltage-flow curve of the nonlinear proportional valve, it can not only fit the voltage-flow relationship of the nonlinear proportional valve well, but also simplify the calculation process and improve the accuracy of the calibration process

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