Device for measuring inspiratory strength with variation of area of air passage(s) in downstream end of chamber, and sliding member in chamber recording inhalation flow rate using calibration marks on chamber

摘要

A device having variable inspiratory resistance suitable for measuring the inspiratory strength of a patient which comprises a chamber (2) in communication with a mouthpiece (4), said chamber (2) (a) being provided with a calibration system (9) for measuring the inhalation flow rate during inhalation through the mouthpiece (4) and (b) being provided with a variable resistance feature (5) by which the resistance to airflow through the device may be altered.