US2431328A - Respiroscope - Google Patents

Description

NOV. 25, I w; HULL RESPIROSCOPE Filed Sept. 15, 1946 2 Sheets-Sheet 1 Ill/ 1 1 a N 0 & 0L V 6 m n 0 N N B H 0 T H m w v. y B

W. E. HULL RESPIROSCOPE Nov. 25, 1947.

I .2 Sheets-Sheet 2 Filed Sept. 15, 1946 l N VEN TOR.

M U E 0 M m w m arms/vans Patented Nov. 25, 1947 RESPIROSCOPE Wayland E. Hull, Dayton, Ohio Application September 13, 1946, Serial No. 696,968

8 Claims.

(Granted under the act The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to a device for continuous observation and rapid estimation of respiratory flow patterns and finds particular utility in observing respiratory phenomena occurring during surgery, clinical studies, and general diagnosis.

One of the essential objects of this invention is to provide a device for rapid and continuous observation of respiratory flow patterns, whereby to estimate rapidly the rate of respiration, the depth of respiration, and the character of the respiratory flow pattern.

Another object of this invention is to provide a novel and accurate device for observing and estimating the respiratory flow pattern, and whereby such observation and estimation can be made rapidly and substantially instantaneously.

Another object of this invention is to provide such a device which is compact and easy to operate and is also very accurate in observation.

Another object of this invention is to provide such a device whichis of great simplicity of construction, this being preferably accomplished by utilizing purely mechanical-optical means.

These and various other objects and advantages are attained with this invention as will become apparent from the following description, taken in connection with the accompanying drawings wherein this invention is shown in its preferred form, it being evident that other arrangements and forms of construction may be resorted to in carrying out the objects and purposes of this invention.

In the drawings:

Fig. 1 is an end elevational view of the invention.

Fig. 2 is a longitudinal vertical sectional view, taken substantially on line 2-2 of Fig, 1, showing the invention in a preferred form.

Fig. 3 is a partial sectional view thereof, taken substantially along line 3-3 of Fig. 2, and showing a double set of manometers and differential pressure devices.

Fig. 4 is a vertical eter.

Fig. 5 is a sectional detail view, taken on line 5-5 of Fig. 4 and showing the tiltable. mirror and its supporting bearing.

This device comprises a viewing screen H, which is preferably fluorescent, and it may be constructed of plastic of optical clarity provided sectional view of the manomamended April 30, 1928;

of March 3, 1883, as 370 0. G. 757) with a fluorescent salt suspended in the solvent for the plastic. This fluorescent screen is movable and is herein shown cylindrical and rotary, being supported by and depending from a circular plate or disc l2 which is splined on and is rotated by a shaft [3 supported rotatively in a bracket l4 mounted in a frame or housing l5. Said shaft is splined to and is driven by a gear l6 actuated by a pinion l1 secured on and driven by the shaft l8 of a motor l9 mounted on said frame l5.

An opticaldifierential manometer 2| (see Figs. 2, 4 and 5) is utilized herein for indicating respiratory flow rates (or other fluid flow rates). It comprises an air-tight housing 22 having a wafer membrane or diaphragm 23 mounted therein by a tubular post 24. The interior of the diaphragm 23 and of the hollow post 24 are in open communication with a channel 25 provided in a wall of said housing 22. A deflecting member 26 is provided in said housing, being shown as a small mirror carried in a frame 21 and is therewith mounted tiltably by jewelled bearing means 28 in a yoke 29 mounted on an apertured disc 30 ex tending across the housing 22. A link 3i extends through the aperture in disc 36, is pivotally connected with the lower part 21 of said frame 2i, and through pivoting means 32 with the forwardly expansible front wall 33 of said diaphragm 23, so as to tilt the mirror 26 on its bearing means 28 when said front wall 33 is moved due to expansion or contraction of said diaphragm. A window opening 35 at one end of the housing 22 is covered by a transparent member 36 secured by a gasket 31, a spacer 38, and a cap 39, to seal the opening air-tight but allowing passage of light rays therethrough.

Projecting means is provided herein. which functions in cooperation with said deflecting member 26, and it comprises a source of light 40, such as an electric bulb, supported by bracket or frame means 4| mounted on the frame l5. A lens system is interposed between said light 46 and the mirror 26 and includes a convex lens 4'2 mounted in said means 4| and a convex lens 43 mounted on a post 44 secured on the frame l5. These lenses and this light are installed so as to produce a beam of light centrally on the mirror 26 which is thereby reflected and caused to fall as a concentrated and intense light spot of small diameter onto the fluorescent cylindrical screen ll, near the central part between the upper and the lower edge of said cylindrical screen.

A differential pressure device is provided which comprises a casing 45 having a porous cross-wall or a plate 46 therein extending centrally therethrough and being of porous or perforated ceramic, or metal so as to divide the casing 45 into two chambers 47 and 48 on the opposite sides of said wall. This will establish a difference in pressure in said chambers 41 and 48 through pressure drop due to the resistance oifered by said porous cross-wall 46 to the gas stream passing through this device. Said chamber 47 has a branch or spout 49 thereon with its end open during air breathing; and said chamber 48 has. a spout 55 thereon adapted for attachment'to the hose of a gas mask, as indicated in the drawings. A pipe or conduit connects said chamber 41 with said channel 25 in the manometer housing 22 and thus places the interiors of the diaphragm 23 and this chamber 4! in communication; while a pipe or conduit 52 likewise connects chamber 48 with the manometer housing 22 to place their interiors in communication.

The pressure drop effected by the porous wall 46 is substantially of the magnitude of 0 to 1, inch of water for flow rates of Oto 150 liters of gas per minute, and is proportional to the velocity of the gas flowing through the casing 45 into or out of the respiratory maskused herewith. Thus, the instantaneous gas velocities are exhibited as mirror deflections on the moving screen by this device. i

To use this device during inhalation of any particular gas, the inspiration spout 49 is not left open to the air but is connected with the tank or container that has the selected gas therein.

This device includes a viewing part or means 53 located and arranged so that a person can thereby see the essential ray-bearing part or area of the screen I and can thereby continuously observe the respiratory flow pattern formed on this rotating fluorescent screen; and to facilitate this, a viewing scope 54 is preferably provided on this part 53, being shown as projecting from frame I5.

Although this invention would function effectively with one such manometer 2| and one pressure device 45, yet, during inspiration and expiration, breathing difficulties may finally result. Therefore, as indicated in Fig. 3,1;WO independent optical manometers with two such pressure de-' vices are preferably used with this invention, and they are mounted beside each other in the frame l5, one manometer 2| and one device 45 being utilized for forming the flow pattern of the 'inspiration and the other for forming such pattern of the expiration on screen The'inspiration pattern is herewith preferably formed as a curve above the middle or zero line on the screen, and the expiration pattern is formed on the screen. Two sets of lenses and lights may be used herewith, as indicated in Fig. 1, for casting sharp beams on the two mirrors; or additional light deflecting members may be associated instead with the one light 48 and its frame means 4| to produce such desired effect.

As indicated in Fig. 2, a gas mask 55 is used with this device; and this mask, as illustrated in Fig. 3, is provided with two branches 56 and 56' for connection with the two spouts 59 of the two manometers preferably being used herein. A check valve 58 is provided in branch 56 toiadapt it for inspiration, and a check valve 58' is included in branch 56 for expiration, bythe u'se of this mask and. device. I

By the use of this device, withthe disclosed twobranch formof gas mask'att'ached to the device, during inspiration the manometer wall 46 of the inspiration means 45, on

below such line.

the left-hand side in Fig. 3, restrains the inflow of air or gas through its spout 49, and the pressure in chamber 41 becomes greater than the pressure in chamber 48 wherein the air has been rarified by the inspiration; consequently, through action of pipe 5|, the pressure in the interior chamber of diaphragm 23, connected through pipe 5|, becomes greater than the pressure within the. manometer housing 22, connected through pipe 52 to chamber 48. The diaphragm thereby expands and causes its wall 33 to push link 3| so as to move the attached lower part of mirror 26 away from the diaphragm.

This will tilt the mirror 26 on its bearings 28, so

asto deflect the light spot further upwardly on the rotating screen above the base or central line thereon, thereby energizing the fluorescent material and causing it to emit light where the spot strikes the same. Thus, as the screen rotates, the upward and downward or substantially vertical movement of the light spot forms a curve on the rotating screen which represents the sum of theinstantaneous inspirational flow rate. Similarly, during expiration thewall 46 of'the expiration casing 45, at the right-hand side in Fig. 3, retards the outflow of air or gas, so that the pressure becomes higher in itschamber 48 than in chamber 47, and consequently, the pressure within housing 22 becomes greater than that within diaphragm 23, thereby'pulling link 3|, and the lower part of mirror 26 toward the diaphragm so as to deflect the light spot lower on the screen, below the middle or base pressure line thereon, thus showing the expirational flow rate.

The luminous curve hereby formedon said screen travels to the viewing scope. 54 and there can be continuouslyobserved-and-substan-a tially instantaneously estimated. 'The fluorescent screen herein is preferably rotated at about" one revolution per minute. Thus, by using a type of fluorescent material in which the image persists for 10 to 30 seconds, the curves formed. dur.-

ing one respiration. cycle traveling a partial rotation beyondthe'iviewable area, and that viewed area of the screenis thereafter again ready for further exictation, before making a complete revolution.

The pair of manometers 2| mirrors 26 are slightly tilted ward the screen and viewing scope, so as to reflect the light rays coming from the lens system closely together on the screen one above and the other below the middle line thereon. These light beams are adjusted tofall to the left or to the right of the center of the viewable area of-the screen or field of vision as seen 'throu gh'the viewing scope, and the direction of rotation of the screen is then such that the patterns formed by respiration are carried into and across the field of vision. Therefore, with this rotary fluorescent screen, elimination of the impingement of light shafts or the movement of light spots within said field of vision, and only the complete patterns arevisible to the observer on this form and type of screen.

Calibration of will disappear after with their pair or the respiroscope is: accom- -plished by forcing known velocities of gas through the differential for inspiration and for expiration. Knowing thetime involved for one respiration and" the maximum of velocity or the estimation can be made of the total. volume, or the amount of gas-breathed,sincef the respiratory pattern is normally a smooth and nearly sinusoidal curve.

and" converged toconfusion is lessened by pressure device 45, both gas flow," a rapid 7 It will be apparent from the above disclosure that with the use of this device, each respiratorypattern maybe immediately observed, and estimations rapidly made of the respiratory rate (respirations per minute), since normally respiration is uniformly cyclical, and if the time involved in one respiration is known, the total number of respirations which may occur in one minute is easily and very rapidly estimated. It is furthermore apparent that this device, for rapidly observing and relatively accurately measuring the respiratory flow pattern, may be used to great advantage in research and clinical medicine, where such means of observing the respiratory pattern immediately is of considerable importance.

I claim:

1. A device for continuous observation of a respiratory flow pattern, said device comprising a rotary screen, viewing means for observing said screen, means for producing a light ray, a manometer provided with means for deflecting the light ray onto said screen, and a differential pressure device arranged for connection with a gas mask to be therewith actuated by respiration of a person to operate said manometer and the deflecting means and vary the position of impingement of the rays onto said screen, whereby the respiratory flow pattern of the person will be translated into a moving light ray on the rotating screen.

2. A device for continuous observation of a respiratory flow pattern, said device comprising a rotary fluorescent screen, a viewing scope for observing said screen, a projecting apparatus for producing a light ray, means for deflecting the light ray onto said screen, means actuated by fluid pressure for moving said deflecting,

means, and a differential pressure device arranged for connection with a gas mask to be therewith actuated by respiration of a person to operate said fluid pressure actuated means and thereby vary the position of impingement of the rays onto said screen, whereby the respiratory flow pattern of the person will be translated into a moving light ray which traces a curve on the rotating screen.

3. A device for observation of a respiratory flow pattern, said device comprising a rotary fluorescent screen, a viewing scope for observing the screen, a projecting apparatus including a reflecting member for producing a light ray on said screen, an expansible member and means operatively connecting it with said reflecting member, and a difierential pressure device including a part open to the atmosphere and a part arranged and constructed for connection with a gas mask and operable by the respiration of the person wearing the mask for actuating the expansible member to tilt said deflecting member and move the position of light on said screen, whereby the respiratory flow pattern of the person will be translated into a moving light ray which traces a curve on the rotating screen.

4. A device for continuous observation of a respiratory flow pattern, said device comprising a rotatably mounted fluorescent screen and means for rotating the screen, viewing means for observing a part of said screen, a projecting apparatus including lighting means and a lens system and deflecting means arranged for causing a beam of light to impinge as an intense spot of light of small diameter onto the screen and to the entrance side of the visible parts of said screen, pressure actuated means to operate said deflecting means, and

a differential pressure device arranged and constructed for connection with a gas mask and thus operable by respiration of a person to actuate said pressure actuated means and deflecting means and thereby move the position of said light spot on the screen at an angle to the movement of the screen, whereby the respiratory flow pattern of the person will be translated into a moving light ray which traces a curve on the rotating screen continuously observable through said scope.

5. A device for continuous observation of a respiratory flow pattern, said device comprising a cylindrical fluorescent screen and means to rotate the screen on its central axis, viewing means positioned to facilitate observing said screen, a projecting apparatus including a reflecting member for producing a light ray on said screen, and means including a fluid pressure sensitive element and a fluid carrying conduit connected to said element for actuating said reflecting member in response to the respiration of a person breathinginto said conduit to vary the position of the light ray on the screen, whereby the respiratory pattern of the person will be translated into a moving light ray capable of tracing a curve on said rotating screen.

6. A device Or continuous observation of a respiratory flow pattern, said device comprising a casing containing a translucent cylindrical fluorescent screen and means to rotate the screen on its central axis, a viewing scope provided on said casing for observing an exterior part of said screen, a projecting apparatus including a member for reflecting a light ray on the interior of said screen, and means including fluid pressure sensitive element and a fluid carrying conduit connected to said element, for actuating said reflecting member in response to the respiration of a person breathing into said conduit to vary the position of the light ray on the screen, whereby the respiratory pattern of the person will be translated into a moving light ray capable of tracing a curve on said rotating screen with said curve continuously observable through said viewing scope.

7. A device for continuous observation of a respiratory flow pattern, said device comprising a cylindrical fluorescent screen and means for rotating the screen on its central axis, a viewing scope for observing a part of said screen, a projecting apparatus including a lamp and a lens system and a mirror arranged for causing a beam of light to impinge as an intense spot of light of small diameter onto the screen and at the entrance side of the visible part of said screen, whereby to prevent moving light spots from impinging on said visible part of the screen, and a differential pressure device including a fluid carrying conduit connected thereto and operable by respiration of a person breathing into said conduit to actuate said mirror and thereby move said light spot on the screen, .in a direction at an angle to the direction of movement of the screen, whereby the respiratory flow pattern of the person will be translated into a moving light ray which traces a curve on said visible part of the rotating screen continuously observable through said viewing scope.

8. A device for observation of a respiratory flow pattern, said device comprising a translucent cylindrical screen and means for slowly rotating the screen on its central axis, a viewing scope for observing an exterior part of said screen, a projecting apparatus and cooperating reflecting enemas means to produce alight ray on the interior side of said screen, means including. a fluid pressure sensitive element and a fluid carrying conduit image persists for only a, part of the revolution 7 of said screen, to equip the screen for continuous excitation, whereby the respiratory flow pattern of the person will be translated into a moving light, raywhichtraces a curve onthe visible part of; said screen. continuously observable. through saidviewing scope. i V .1 v -WAYLAND REFERENCES CITED The following references file of this patent:

UNITED STATES PATENTS Number Name Date 2,274,182 Asher Feb. 24,1942

t 2,371.;244 Lax Mar, 13, 19 45 are of record in the"

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