Device for measuring the flow-volume of pulmonary air
First Claim
1. Medical device for measuring the flow-volume of pulmonary air breathed out by a subject, comprising a sound generator, an inlet in fluid communication with said sound generator and into which the subject blows, and a resonance chamber in fluid communication with said sound generator arranged to produce, under the effect of said blow, a note of predetermined frequency and amplitude, means for measuring the length of said note, and a by-pass outlet disposed between said inlet and said sound generator having means to adjustably and measurably vary the opening/closing of said by-pass outlet, the varying means reducing or increasing the amount of air which passes through said sound generator wherein by making measurements ar various openings of said by-pass outlet, the parameters of the expiratory flow-volume curve of the subject can be calculated.
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0 Petitions
Accused Products
Abstract
The apparatus is comprised of a connection conduit comprising a mouth piece at one of its extremities, a sound generator provided with a nose, as well as a digital time measuring unit. A tapping exhaust orifice allows to tap a portion of the expired air. The orifice has an opening which is adjustable by simply turning a cuff, screwed on the outside of the conduit. When the patient expires in the apparatus, only a well defined fraction of the airflow is directed towards the sound generator, the remainder being eliminated in the atmosphere through the tapping exhaust. The airflow which remains is directed through the sound generator wherein a well defined note is produced.
41 Citations
22 Claims
- 1. Medical device for measuring the flow-volume of pulmonary air breathed out by a subject, comprising a sound generator, an inlet in fluid communication with said sound generator and into which the subject blows, and a resonance chamber in fluid communication with said sound generator arranged to produce, under the effect of said blow, a note of predetermined frequency and amplitude, means for measuring the length of said note, and a by-pass outlet disposed between said inlet and said sound generator having means to adjustably and measurably vary the opening/closing of said by-pass outlet, the varying means reducing or increasing the amount of air which passes through said sound generator wherein by making measurements ar various openings of said by-pass outlet, the parameters of the expiratory flow-volume curve of the subject can be calculated.
Specification