Surgery – Truss – Pad
Patent
1991-08-01
1994-04-26
Cohen, Lee S.
Surgery
Truss
Pad
128719, A61B 5091
Patent
active
053057635
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The invention concerns an expiratory air reception vessel for the measurement of lung function having an inlet.
2. Description of the Prior Art
In order to determine the performance and/or detect diseases of the lung, it is known how to record and at the same time analyze the volume and composition of the expired air from a test person under conditions of changing levels of physical exertion. Of particular interest are the respective proportions of oxygen and carbon dioxide. The concentration of the expired air is subject to fluctuations caused by changes in levels of exertion, and these should be recorded and indicated as soon as possible. These requirements are met by mass spectrometers, which, however, are enormously expensive and costly to procure and maintain. For this reason, expiratory air is, at the moment, fed into a bag with an outlet, so that part of the air found therein can escape and an overloading can be safely ruled out. A part of the air collected is removed and undergoes analysis as regards its composition. Here the disadvantage is that with a changing concentration of expired air, due to the immediate loss and the large volume of this air, the composition in the bag only changes very slowly. The time constant for the measurement of changes in the concentration of the air taken from the bag with the aid of a gas analyzer is therefore considerable. Moreover, it would be desirable if the volume of expired air could be determined.
SUMMARY OF THE INVENTION
On this basis, it is the object of this invention to provide an expiratory air reception vessel that possesses a short response time, is of simple construction and which, in addition, makes it possible to measure the volume of expired air.
In accordance with this invention, this task is solved by means of two inlets disposed opposite each other in a closed container, which can admit expired air alternatively, whereby the container comprises a piston disposed inside, which is movable in a direction towards the inlets, as well as switches, which are operated when the piston reaches the wall of the container, whereby the inlet to be pressurized is changed.
Utilization is in the usual way, i.e. the expired air from the test person is fed from the mouth piece to the inlet and enters the interior of the closed container. In accordance with the concept of the invention, only one single inlet is ever pressurized. As a result, an overpressure arises in the space defined by piston, corresponding wall of the container and inlet pressurized at that moment, causing the piston to move towards the inlet opposite, where, upon reaching the corresponding wall surrounding the inlet, it operates a switch. Consequently, a change in pressurization of the two inlets is achieved, i.e. the expiratory air supplied from now on moves the piston in the opposite direction and it presses the air there outwards. The piston support shall be, as far as possible, friction-free, so that the resistance to be overcome by the expired air remains low and natural conditions prevail during expiration. Because of the geometry of the receptacle, an exact determinable volume and thus volume of air expired is defined. As a rule, dimensioning will be such that several expiration processes fill the whole volume. An average of the gas concentration is formed during the course of several expiration processes. When the volume built up is eventually is emptied by means of a return movement of the piston, a part of the gas mixture there can be removed and supplied to a gas analyzer. One measures the mean value during the course of several expiration processes.
As a decisive advantage can be seen, firstly, that the measured volume is always constant and changes in the composition of the expiratory air can be recorded and undergo analysis relatively rapidly, since the reversal in the direction of the movement of the piston builds up a gas volume fully new in composition; the mean being taken during the course of several expirat
REFERENCES:
patent: 3669097 (1972-06-01), Fitz
patent: 3754546 (1973-08-01), Cooper
patent: 3793888 (1974-02-01), Rosenwald
patent: 4947860 (1990-08-01), Fisher
Cohen Lee S.
Gilbert Samuel
Schindler Edwin D.
LandOfFree
Expiratory air reception vessel does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Expiratory air reception vessel, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Expiratory air reception vessel will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1705921