Self-powered gas flow control pipe fitting

Abstract

The invention discloses a self-actuated air flow control pipe fitting. The pipe fitting comprises a tubular valve body and an air inlet orifice plate and an air outlet orifice plate; the air inlet orifice plate is sealed by one end of a conical valve core which is matched with a moving orifice plate and a spring in the valve body, and the other end extends into the air outlet orifice plate to form an outlet circulation annular space. Air flow passes the air inlet orifice plate to propel the conical valve core to shift along the flow direction, thus changing area of the circulation annular space. The area of the circulation annular space decreases if the air flow pressure increases; the area of the circulation annular space increases if the air flow pressure decreases; meanwhile, adjustment and control of the self-actuated flow rate are realized by dynamic compensation of the compression force of the spring and change of equilibrium pressure. The pipe fitting is characterized in that the pipe fitting is only provided with an air chamber, and one valve core in the air chamber has both functions of starting a self-actuated valve and adjusting the flow rate, thus the pipe fitting has the advantages of simple and compact structure, small size, and convenient manufacture and use, and the pipe fitting is especially suitable for the flow control within the exhalation pressure range.

Description

technical field

[0001] The present invention relates to a gas flow control device, more specifically, to a self-operated gas flow control tube device especially suitable for exhalation detection. Background technique

[0002] Breath testing is a diagnostic method for detecting the concentration of gas molecules in exhaled breath as disease markers for disease judgment. Usually the concentration of markers is related to the expiratory flow, for example, the concentration of nitric oxide in exhaled air, which is a marker of airway inflammation, decreases with the increase of expiratory flow. In order to ensure the consistency of breath test results, it is necessary to control the expiratory flow within the normal range of expiratory pressure variation. For example, for the detection of exhaled nitric oxide, the current international standard recommends that the expiratory pressure of 50mL / s or 3L / min can be controlled within the range of 5-20cmH20 or 500-2000Pa expiratory pre...

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