US2550810A

US2550810A - Means for cooling air or oxygen enriched air within an enclosure

Info

Publication number: US2550810A
Application number: US728034A
Authority: US
Inventors: Jay A Heidbrink
Original assignee: Air Reduction Co Inc
Current assignee: Airco Inc
Priority date: 1947-02-12
Filing date: 1947-02-12
Publication date: 1951-05-01
Anticipated expiration: 1968-05-01

Description

A. HEIDBR NK 2,550,810

May 1, 1951 J,

MEANS FOR COOLING AIR OR OXYGEN ENRICHED AIR WITHIN AN ENCLOSURE Filed Feb. 12, 1947 2 Sheets-Sheet l INVENTOR JAY A. HEwBmNK "WWW y 1951 J. A. HEIDBRINK 2,550,810

MEANS FOR COOLING AIR 0R OXYGEN ENRICHED AIR WITHIN AN ENCLOSURE Filed Feb. 12, 1947 2 Sheets-Sheet 2 Fl .3 /8 9 r l i n L L 8 T INVENTOR.

JAY A. HEIDBRKNK Patented May 1, 1951 UNITED STATES PATENT OFFICE MEANS FOR COOLING AIR OR OXYGEN ENRIOHED AIR WITHIN AN ENCLOSURE Jay A. Heidbrink, Minneapolis, Minn., 'assignor to Air Reduction Company, Incorporated, New York, N. Y., a corporation of New York Application February 12, 1947, Serial No. 728,034

I Claims.

1 My invention relates to a means for cooling air or oxygen enriched air within an enclosure whichis adapted tosurround a bed. In particular it relates to means for cooling the atmosphere within an enclosure when the atmospheric temperature surrounding the enclosure is excessively high. On administering oxygen therapy to a patient it is essential that the air which surrounds the head of the patient should be enriched with oxygen and it should be cooled to a point below what is regarded as normal room temperature, and should preferably be to about 65 F., as the lowered temperature tends to inhibit bacterial activity. The .particular advantage of thepresent invention is that when the temperature of the air surrounding the enclosure is excessively warm, as for example near or above 90 F., room temperature, the air mixture supplied to the patient can be maintained at the desired lower temperature.

In the past, the generalipracticerelating to this subject matter was to introduce cooled air through the side walls of the enclosure that surrounds the patient at a point spaced above the .pati'ents head and in such a manner that the incoming air "was directed toward the walls of the enclosure so as to avoid a direct draft on the patients face. In this manner the cooled air initially carhe into contact with the Walls of the enclosure from which it was deflected in a turbulent manner above the patients head. Under conditions of reasonably moderate temperatures the prior art arrangement was satisfactory, but difficulty arose when the temperature surrounding the enclosure became excessively high, for under these conditions the cooled air absorbed so much heat from the walls of the enclosure that it could not be maintained at the desired lowered temperature. It was the practice when atmospheric temperatures were high to increase the rate of air flow into the enclosure to compensate for the gain in heat but this was not satisfactory because it created an intolerable draft on the patient and failed to keep the air properly cooled.

thereon, and is constructed in such a manner as to "direct the flow of cooled air in a quiescent manner with virt'ually'no turbulence in a downward direction and around the head of the person. Meansare also provided for withdrawing the warmer air from within the top of the enclosure so as to create cyclic passage of air through the enclosure.

The principal value of the distributor is for diff-using the incoming air without turbulence and with a minimum absorption of heat. For this reason, the connection between it and the air cooling apparatus is as short as possible and is situated .principally within the enclosure where it will be subject to a cooler exterior temperature and will, therefore, absorb less heat. Furthermore, the distributor is carefully heat insulated from the enclosure and is arranged in spaced relation to the side walls to cause the cooled air leaving the distributor to descend in a central column within the enclosure until it reaches the surface of the bed, after which it spreads out and ascends in the form of an annulus. Also the distributoris constructed with such large area of discharge openings that the air leaves it at a reduced velocity and free of turbulence. The cyclic travel of the air is brought about by heat transfer which occurs through the side walls of the enclosure since it 'is a natural tendency for air to rise when heated, and to "aid in this action the means for withdrawing the air from within the enclosure is situated preferably to open adjacent its upper portion.

However, when the temperature of the atmosphere surrounding the enclosure, is not excessively high, and may for example be less than about F., the cyclic distribution of air, through the absence of a rapid transfer of heat, will tend to create an excessively cooled condition within the enclosure. Under these conditions, means are provided for diverting the flow of incoming air from the distributor and directing it against the walls ofthe enclosure to create a turbulent condition and to bring the incoming air quickly into contact with the walls so as to create a more rapid transfer of heat and thus prevent the air within the enclosure from being excessively cooled. Thus the cooling within the enclosure is maintained substantially constant with considerable variations of surrounding room temperature.

An object of my invention is to provide means for cooling the air within an enclosure which is adapted to surround abed.

Another object is to provide means used in combination with air conditioning apparatus for cooling the atmosphere within an enclosure so as to maintain the air entering the enclosure cooled when the atmospheric temperature surrounding the enclosure is excessively high.

Another object is to provide in combination with an air conditioning apparatus, means for introducin cooled air into an enclosure which is subject to a relatively higher temperature on its exterior surface, in such a manner as to form a central column of descending non-turbulent cooled air which is separated from the walls of the enclosure by an ascending annulus of warm air.

Another object is to provide in combination with an air conditioning apparatus and an enclosure having an air distributing means therein, a conduit forming a short connection between the apparatus and the distributing means for conducting the cooled air thereto, which is situated within the enclosure and subject to the temperature of the atmosphere within the enclosure.

Another object is to provide in combination with an enclosure having a cool air conduit entering therein, means for distributing the cool air in said enclosure in a non-turbulent descending column.

Another object is to provide in combination with an air conditioning apparatus and an enclosure a first means of distributing cooled air within the enclosure when the temperature of the air surrounding the enclosure is relatively high, and a second means of distributing the air within the enclosure when the temperature of the air surrounding the enclosure is relatively moderate.

A further object is to provide in combination with oxygen therapy equipment a means of providing a therapeutic air within an enclosure which is adapted to surround the head of a person reclining on a bed by providing means for diffusing the therapeutic air within the enclosure in a quiescent manner and wherein the diffuser is situated with relation to the side walls of the enclosure so as to provide a central column of descending cool air which when it comes into contact with the bed will spread out and rise by virtue of heat absorbed from the side walls, the bed, and the enclosure, and preferably be removed from a point adjacent the top of the enclosure.

Other and further objects may become apparent from the following description and claims and from the appended drawings in which:

Fig. l is a side elevation of the invention with some parts broken away and others shown in cross-section;

Fig. 2 is a plan view taken on the lines 22 of Fig. 1 looking in the direction of the arrows;

Fig. 3 is a side elevation of the structure shown in Fig. 1 as seen from the left side thereof.

Fig. 4 is a enlarged detailed view of a part of one of the conduits shown in Fig. l; and

Fig. 5 is an enlarged detailed view of a portion of the supporting structure shown in Fig. 1.

Referring now to the drawings, the invention will be described in detail.

Referring now to Fig. 1, reference numeral 8 indicates a bed, which is here shown as ,a hospital bed over which is suspended a hood indicated by the general reference numeral i0. Hood I0 is intended to be positioned with relation to bed 8 so as to surround the head of a patient reclining thereon. Hood 58 has a top portion l2 which is oval in shape as shown in plan view in Fig. 2. About the lower edge of top portion 12 is a rim or beading it. Secured about outer periphery of top portion i2 above beading M by a drawstring I6, is a curtain I8. Curtain l8 may be formed of a transparent plastic. such as 4 Vinylite, and because it is relatively thin will readily transfer heat to its inside surface. Situated in the under surface of the top portion I2 is an air distributor 20 which has a plurality of small regularly spaced apertures 22 on its lower surface as shown in Fig. 2. Distributor 2!! which is in the form of a shallow pan is heat insulated from top portion 22 by a layer of insulation 24 and is secured to top portion l2 by a plurality of fastening means 28 which extend through insulation 24. Distributor 251 is provided with an enlarged aperture 28 at one end of its lower surface which receives a metal end portion 30 of a conduit indicated by the general reference numeral 32. The combined area of the apertures 22 is greatly in excess of the area of inlet opening 28.

Conduit 32 is provided for supplying air to distributor 20 and is formed of a lower portion 34 having at one end thereof a flange 38 which extends to an open branch 38. Portion 34, above branch 38 is connected to portion 38 by a length of flexible corrugated rubber tube 30. As more clearly shown in Fig. 4, branch 38 extends at right angles to portion 34 and is provided with a damper d2 which is pivoted at ts and controlled by a manually operable lever 46.

Also situated within hood Hi, is a second conduit 5e formed of an elbow 5! having a flanged end portion 52. Extending upwardly from elbow 5! is a flexible corrugated rubber tube 54 which is open at its top portion and which extends up wardly within hood H) adjacent curtain l8 torminating at a point adjacent one side of dis-' tributor 28, as clearly shown in Figs. 1 and 2.

Indicated by general reference numeral 60 is an air conditioning apparatus which is used in combination with hood Iii to withdraw the air therefrom and purify and cool the air before returning it to the hood. Apparatus 68 consists of a casing 82 which has extending from an upper side portion, a conduit 64 having a flanged portion 68 which is joined by a plurality of fastenings to flanged portion 52 of elbow 5| on either side of an aperture extending through curtain I8. Conduit 64, within casing 62, terminates in a container 68, which within its interior, is provided with a portion N! that contains a quantity of soda lime. A conduit 72 extends from the lower portion of container 68 and enters one side of centrifugal pump 14, whose impeller 16, is controlled by a motor 18 to withdraw the air from hood l0 through the connection previously mentioned and drive the air through an outlet 80. The outlet 88 of pump M is connected to a refrigeration evaporator 82 which contains a cooling coil 84. Evaporator 82 has extending from its upper portion a short conduit 86 having on its exterior end a flange 88 which is joined to flange 36 of conduit 32 through an aperture in curtain 18. A thermometer 90 indicates the temperature of the air leaving evaporator 82 through conduit 86 and will in general be indicative of the temperature of air passing into hood in.

A cylinder 92 containing compressed, pure oxygen, supplies additional oxygen to the circulated atmosphere through a control valve 94 and a conduit 98 which extends into connection between pump it and evaporator 82.

In order to provide refrigeration for evaporator 82, a conventional motor-operated refrigeration compressor indicated by the general reference numeral 9'! is connected by a conduit 98 to refrigeration coil 84 to provide fluid refrigerant therefor. In place of the air-cooling. means.

'i'Od H6 and Slidably engages Slot I I0.

tween evaporator 82 and distributor 20. of its large area and the great number of apertures 122 on its 'lower surface, the air entering As'shown'inFigs. 1, 3 and 5, hood It is supported by apparatus 60. A shaft I which is mounted on one side of casing 62'has-adjacent its upper portion 'a pivot 102 on which is pivot ally mounted a hinged portion 104. Hinged portion I I14 hasextending from one side a handle I06 by which portion Hi l-may be pivotally rotated on pivot Hi2. Extending in the same plane as "handle 106 and "forming an angular part of portion 5 I04 is an upper portion I08 which has on one side'thereof a slot l Ill having'an upwardly extending terminal portion H2 at one end and 'adownwardly extending terminal portion ifi'at the other end. Tubular portion [98 is adapted to receive one end'of a rod HG, which through brackets H8 supports hood I'll 'from itstop portion l'2. Apin I29 is'po'sitioned on one end of Hood It is, under certain conditions, adapted to'be folded alongside of apparatus is and to accomplish this, rod 116 is lifted-at its outer end to disengage pin "I20 from the terminal portions H2 of slot Ht,

thereafter-rod I I6 may be moved outwardly permitting pin i-2E) to slidably move along slot i Ill until'it is'turned andengaged in a terminal portion IM of slot H0, whence hood Ii! will be folded in a vertical position alongside of apparatusi'il).

Iii-operation, the invention performs in the following manner. With 'the hood is surrounding a portion of be'd8 so as to enclose the head and upper'part of the patient reclining thereon, it is necessary to continuously supply oxygenenriched air to the'hood which must be at a temperature lower than that surrounding the exteriorof the hood.

Assuming the temperature of the air surrounding hood Ill to be about 85 to 90 F. or higher, damper 42 will be adjusted by handle "46 so as to direct the flow of air entirely into distributor 20. 'with apparatusfifl in operation, the air within hood -ifi willbe in continuous circulation through the various elements of apparatus 60, and cooled air will be transmitted through conduit 32 to distributor 20. It will be :noted'that conduit 32 is positioned within heed ID and forms a relatively short connection bedistributorZil loses its velocity and descends into :hood [-0 without turbulence and with'no appre- "ciable "force. tributor :20 is centrally disposed in hood ill in spaced relation to curtain i8 so that the cool air As clearly shown in Fig. 2, dis

ature on the outer surface :of curtain i3 being relatively high, the curtain will form a radiating surface and .as the air contacts the curtain it will .absorbheat and rise in the form of an annulus adjacent the curtain. As the warm air .rises rwithin hood l0 "it will be withdrawn near the upper portion-of the hood through theupper open "end of rubber tube 5d. Thus the cooled airentering the hood is insulated from the heat "being radiated from the curtain by the ascending annulus-0f warmer air and because conduit Because I 32 is comparatively sh'ort in length and 'is situated within the hood the incoming air reaches the patient at a comparatively low temperature even though a much higher temperature "exists in the area surrounding tth'eiihood.

The airentering apparatus 60 hasrits carbon dioxide content removed by the soda lime in container 68 and its oxygen supply em'iched by pure oxygen from cylinder '92. The evaporator 82 cools and conditions the air before it is returned to conduit32.

When the "temperature of ambient air surrounding hood 18 .is within a more moderate range, 'asfor example in the range of under 85 R, :the non-turbulent cycle previously disclosed will tendtocause the air surrounding thegpatient to become excessively cooled because of the slower rate of heat transfer through ourtain I18. Under these conditions, damper42 is moved to divert the now of air from distributor '20, through the branch opening 38 intothe area of hood Iii above the patients body and in the direction of curtain [8. This will terminate the thermal cycle and cause "a turbulent agitation of the air so that all of the air within hood i0 is brought into contact'withcurtain [8 to cause a more rapid rate of heat transfer and thusv raise the temperature within :hood ill and maintain it at a higher level.

If the temperature produced by distributing the air through distributor 2!] is excessively low and the temperature resulting from distributing all of the air through branch 38 is excessively high, damper 12 may be positioned at an intermediate position to distribute a'portion of the air through "distributor Zfi-and aportion through branch 38, so that'a range-of temperatures within hood it may be obtained by regulating the position of damper 42.

The principal advantage of my invention is that a suitable lowered temperature may be maintained within an enclosure when the exterior temperature is very high by providing for the cooled incoming air to descend in a nonturbulent central core within the enclosure in such a manner thatlthe central core is insulated from the walls of the enclosure by a rising annulus of warmer air. On the other hand, when the ambient temperature is in a more moderate range, the air within the enclosure may be agitated in 'varying'degrees to prevent it from becoming excessively cooled.

Another advantage is that by providing a relatively short connection between the air-cooling means and the distributor, which connection is situated substantially entirely within the enclosure, the air passing from the cooling means to the distributor will not be subjected to atmospheric temperatureexisting on the outside of the connection and will, therefore, berelatively .cool when .it reaches the distributor.

apertures for emitting the cool air, the combined area of which is considerably in excess of the area of the conection to the distributor, the" force of the air leaving it is greatly diminished so that the air descends within the enclosure principally by virtue of its "lowered temperature,

As numerous changcs may beapparent to those a. 7 skilledin the art, my'invention is not limited to the single illustration, but is defined in the terms of the appended claims.

I claim:

1. In an air conditioning system, in combination, an enclosure for surrounding a portion of a bed and formed of a top wall and side walls, an outlet conduit connected to said enclosure for conducting air from within the enclosure, air conditioning means connected to said conduit and being operative to continuously withdraw and cool the air from within said enclosure, an air distributor consisting of a shallow member supported within the interior of the enclosure beneath the top wall and extending over the major portion of the interior of the enclosure and having its outer edges spaced inwardly from the side walls, the lower surface of said distributor hav ing a plurality of substantially regularly spaced openings, a second conduit connecting said air conditioning means and said distributor to return conditioned air to the'interior of said enclosure, said second conduit having an opening therein which is spaced beneath and at one side of the lower surface of the air distributor, and a damper associated with the opening in said second conduit for venting a portion of return air from said second conduit in a substantially lateral direction with respect to the openings in the lower surface of the air distributor.

2. In an air conditioning system, in combination, an enclosure for surrounding a portion of a bed and formed of a top wall and side walls, air conditioning means for supplying cooled conditioned air to the interior of said enclosure, and an air distributor consisting of a shallow member wholly contained within the interior of the enclosure beneath the top wall, said distributor having an inlet opening connected to said air conditioning means for receiving cooled conditioned air, the lower surface of said distributor having a multiplicity of small substantially regularly spaced outlet openings, the total area of the outlet openings being substantially greater than the area of the inlet opening to reduce to substantially nil the velocity of air leaving the distributor, said distributor extending over the major portion of the interior of the enclosure and having its outer edges spaced inwardly from the side walls of the enclosure, whereby the cooled conditioned air leaving the distributor forms a quiescent descending column within a central area of the enclosure.

3. In an air conditioning system, in combination, an enclosure for surrounding a portion of a bed and formed of a top wall and side walls, an air distributor consisting of a shallow member supported beneath the top wall and extending over the major portion of the interior of the enclosure and having its lateral edges spaced inwardly from the side walls, the lower surface of said distributor having a multiplicity of substantially regularly spaced outlet openings for distributing air downwardly within the enclosure, said distributor having an inlet opening, air cooling means positioned in close relationship to the enclosure and having an outlet opening for cooled air extending in the direction of a side wall of the enclosure, and a conduit extending through the side wall of the'enclosure and connecting the outlet opening of the air cooling means with the inlet opening in said distributor, said conduit having substantially its entire linear portion within the enclosure and in contact with the cooled air passing from the entire linear portion within the enclosure and in contact with the cooled air passing from the distributor to minimize the gain in temperature of the cooled air as it passes from the air cooling means to the distributor.

4. In combination with an enclosure including side walls adapted to surround a portion of the bed, a top secured to the side walls, an outlet conduit connected to said enclosure for with- 10 drawing air adjacent an upper peripheral portion of the top of said enclosure, air conditioning means connected to said conduit and being operative to continuously withdraw and cool the air within said enclosure, and an air distributor sup- 5 ported by the top and wholly contained within the interior of the enclosure and connected to said air conditioning means to return cooled air to said enclosure, the peripheral limits of said distributor being spaced inwardly from the side walls of the enclosure, said distributor having an inlet opening and a multiplicity of downwardly projecting outlet openings, the combined area of the outlet openings being substantially greater than the area of the inlet opening so that the 5 cooled air leaving the distributor is in a quiescent condition and is spaced inwardly from the side walls of the enclosure to form a central descending column that displaces the air within the central part of the enclosure and causes the same to rise in the form of an annulus surrounding the descending column and extending continuously between the descending column and the surrounding walls of the enclosure.

5. In an air conditioning system, in combination, a hood having a top, a flexible fabric curtain formed of material having a relatively high heat transfer capacity depending from the top and adapted to surround a portion of a bed, a conduit extending from a source of cooled air and 0 penetrating the fabric curtain, a hollow box-like air distributor wholly contained within the fabric curtain and supported by the top, the peripheral limits of said air distributor being spaced inwardly from the fabric curtain, said distributor 5 being connected to the other end of said conduit, said distributor having a multiplicity of small openings in its lower surface, the total area of said openings being substantially less than the area of a cross dimension of the conduit for reducing to substantially nil the velocity of air leaving the distributor, whereby the cooled air descends in a central column within the interior of the fabric curtain, and a controlable opening in said conduit within the interior of the fabric curtain for directing a portion of the cooled air into contact with the descending central column to agitate the air within said enclosure.

JAY A. I-IEIDBRINK.

REFERENCES orrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS 15 2,310,222 Deverall Feb. 9, 1943