Pneumotach and components therefor
First Claim
1. A pneumotach flow tube with a mouthpiece end and an opposite end, with at least said mouthpiece end being of generally cylindrical construction, said opposite end being at least substantially closed against the passage of exhaled air therethrough, said flow tube having a substantially non-porous mouthpiece portion and a substantially porous portion between the non-porous portion and the closed end, a transverse pressure tap opening through the cylindrical wall of said substantially non-porous portion, said opposite end and said pressure tap opening each being located so spaced from the mouthpiece end and the porosity of the porous flow tube portion being so sized, to be sufficient to produce substantially laminar flow in the tube and to permit substantially linear flow pressure measurements through the tap opening at the location of said pressure tap opening.
7 Assignments
0 Petitions
Accused Products
Abstract
A pneumotach is provided that is effective for obtaining accurate flow measurements through a wide range of velocities by measuring substantially linear flow, and which includes a readily disposable element. The pneumotach also includes a holder adapted for readily holding the disposable element in a manner so as to be substantially free of patient contamination, and with transducer capability for detecting pressure and measuring the same at low flow rates. A combined pulmonary functioning measuring kit includes computer and read-out capabilities for selectively receiving input from either spirometer or the pneumotach. The kit is readily assembled and is self-contained.
54 Citations
4 Claims
- 1. A pneumotach flow tube with a mouthpiece end and an opposite end, with at least said mouthpiece end being of generally cylindrical construction, said opposite end being at least substantially closed against the passage of exhaled air therethrough, said flow tube having a substantially non-porous mouthpiece portion and a substantially porous portion between the non-porous portion and the closed end, a transverse pressure tap opening through the cylindrical wall of said substantially non-porous portion, said opposite end and said pressure tap opening each being located so spaced from the mouthpiece end and the porosity of the porous flow tube portion being so sized, to be sufficient to produce substantially laminar flow in the tube and to permit substantially linear flow pressure measurements through the tap opening at the location of said pressure tap opening.
Specification