US3711071A

US3711071A - Humidifier

Info

Publication number: US3711071A
Application number: US00150488A
Authority: US
Inventors: N Urbanowicz
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-07-30
Filing date: 1971-06-07
Publication date: 1973-01-16
Anticipated expiration: 1990-01-16
Also published as: AU3116871A; SE7109697L; NL7109354A; DE2134947A1; CH528309A; BE770229A; IT941578B

Abstract

A device for controllably increasing the relative vapor content, particularly the humidity of a gas comprising, a body having a chamber with a sump in the lower portion, means for admitting fluid opening into said sump, disc means in said chamber rotatable with a sector of its marginal edge in said sump, means for rotating said disc at a speed which is sufficiently high to nebulize fluid within said chamber by the agitating action of the rotating disc member so as to increase the relative humidity of a gas passing through the chamber, inlet means opening into said chamber for admitting gas to said chamber and outlet means opening out of said chamber for withdrawing gas therefrom, said inlet and outlet means being disposed on opposite sides of said disc member.

Description

United States Patent [191 Urbanowicz 1 Jan. 16,1973

1541 HUMIDIFIER [76] Inventor: Nikodem N. Urbanowicz, 151 Albion Street, Brantford, Ontario, Canada [63] Continuation-impart of Ser. No. 59,487, July 30,

1970, abandoned;

2,099,667 11/1937 Howse et a1. ..261/90 3,353,337 11/1967 Gale ..261/92 2,243,839 6/1941 Dalton .....261/92 2,471,724 5/1949 Christensen ..261/92 Primary Examiner--Tim R. Miles Assistant Examiner-Steven H. Markowitz Attorney-Philip T. Mitches [57] ABSTRACT A device for controllably increasing the relative vaporcontent, particularly the humidity of a gas comprising, a body having a chamber with a sump in the lower portion, means for admitting fluid opening into said sump, disc means in said chamber rotatable with a sector of its marginal edge in said sump, means for rotating said disc at a speed which is sufficiently high to nebu 1ize fluid within said chamber by the agitating action of the rotating disc member so as to increase the relative humidity of a gas passing through the chamber, inlet means opening into said chamber for admitting gas to said chamber and outlet means opening out of said chamber for withdrawing gas therefrom, said inlet and outlet means being disposed on opposite sides of said disc member.

13 Claims, 14 Drawing Figures PATENIEDJAH 16 1975 3,711,071

sum 2 OF 6 igma ATTORNEYS PATENTEDJAH 16 4973 SHEET 3 [1F 6 I N V EN'TUR.

NIKOOEM M uEBA/VoN/cZ.

ATTORNEYS sum 0r 6 m N ukamvow/rz ATTORNEYS PATENTEDJAN 16 1915 3.711.071

sum 5 or e INVENTOR.

MK QEM M AIRBANONICZ ATTORNEYS HUMIDIFIER CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of application Ser. No. 59,487, filed July 30, 1970, now abandoned.

This invention relates to a device for controllably increasing the vapor content of a gas. In particular, this invention relates to a device which is particularly suitable for increasing the relative, humidity of anaesthesia gases to prevent dehydration of a patient under an anaesthetic.

PRIOR ART When anaesthesia gases are given to a patient undergoing medical treatment, it is found that the patients lungs and other organs become dehydrated. This dehydration can seriously affect the health of the patient and the conventional practice is to attempt to correct this problem by intravenous injections. The dehydration of the patient results from the fact that the anaesthetic gases do not contain the moisture present in the normal atmosphere. To date, no devices have been developed which are capable of controlling the increase in relative humidity of the anaesthesia gases while they are being administered. The difficulties arising in attempting to provide a device for increasing the relative humidity are that it must be capable of increasing the humidity very quickly so as to be effective while the gases are being administered and in addition, the device must be capable of operating without producing any restriction in the flow of a gas to a patient. For example, any device which creates any substantial amount of back pressure would not be acceptable as this would make it difficult for a patient to receive a rapidly increased (accelerated) flow of anaesthetic on demand. The amount of moisture which may be required in anaesthesia gases may vary depending upon the requirements of a particular patient and, as a result, it is necessary to provide a device capable of controlling the relative humidity of a gas and, for the reasons described above, it must be possible to control the relative humidity of the gas over a range of supply volumes.

The problem of increasing the vapor content ofa gas or air is one which is encountered in many fields other than the one described above. For example, there are many industrial applications such as vaporization of fuels, the curing of tobacco,.water washing and humidifying ventilating air and chemical spraying in which large volumes of air may be processed and in which large droplet sizes are acceptable. Conventional vaporizers such as domestic vaporizers rely exclusively on evaporation. In one known structure a drum which is covered with an absorbent material is adapted to rotate in the air intake of a domestic furnace. The humidifying action which takes place is the direct result of the evaporation of the moisture from the surface of the drum, in that, it relies to a large extent upon the fact that the air is drawn rapidly over the moist surface of the drum. This type of apparatus is not capable of increasing the relative humidity of the air very rapidly and it relies upon the fact that in domestic applications the air is recirculated numerous times to step up the humidity in each pass. This type of gradual increase in humidity is not suitable for many industrial applications.

SUMMARY OF INVENTION stipulated by clinical requirements. The apparatus is also capable of introducing anaesthetics or other medicaments into a gas stream either alone or together with water.

The present invention overcomes the difficulties of the prior art described above by providing a device for controllably increasing the relative humidity of a gas. The device comprises a body having a chamber and a disc member mounted for rotation in the chamber. The device also has means for admitting fluid such as water to the chamber and inlet and outlet means whereby a gas may pass through the chamber. The disc member has means for rotating it within the chamber at a speed which is sufficiently high to nebulize the fluid (water) within the chamber by the agitating action of a rotating disc member to thereby impart fluid vapor (water) to the gas passing through the chamber to increase the vapor content (relative humidity) of the gas.

PREFERRED EMBODIMENT The invention will now be described by way of example reference being had to the accompanying drawings in which FIG. 1 is a pictorial view of a device according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of the device of FIG. 1 showing a pair of discs mounted for rotation within its chamber.

FIG. 2a is another embodiment of FIG. 2 including fixed baffles.

FIG. 3 is a pictorial view of a pair of discs and the inlet and outlet passages of the chamber illustrating a typical flow path for I a gas passing through the chamber;

FIG. 4 is a diagrammatic illustration of an anaesthetic circuit illustrating the manner in which the device of the present invention may be used in anaesthetic applications.

FIG. 5 is a diagrammatic illustration of a valve for proportionally controlling the amount of gas passing through the device of FIG. 1.

FIG. 6 is a partially sectioned pictorial view of an alternative form of disc; and

FIGS. 7 to 12 inclusive are plan views illustrating alternative disc construction.

FIG. 13 is a cross-sectional view of FIG. 2a.

Referring to FIG. 1 of the drawings, the reference numeral 10 refers generally to a device (nebulizer) for controllably increasing the relative humidity of a gas according to an embodiment of the present invention. The device 10 comprises a housing 12, a frame 14, and a motor 16. The frame 14 consists of a horizontal platform 18 which has an upright flange 20 at the front end thereof and an archshaped support bar 22 at the rear end thereof. Flange 20 and arch support 22 serve to support the motor 16. The motor 16 is secured at the front end to the flange 20 by set screws 24.

The motor 16 is preferably a variable speed motor so that the nebulizing conditions prevailing within the chamber 12 may be adjusted by adjusting the speed of rotation of the motor as will be described hereinafter.

The housing 12 consists of a cylindrical shaped wall 26 and oppositely disposed disc-

shaped side walls

28 and 30. An input vapor trap 32 is mounted on the wall 30 and an output vapor trap 34 is mounted on the wall 28. The wall 30 has a passageway 36 communicating with the vapor trap 32 and the wall 28 has a passageway 38 communicating with the vapor trap 34. An input passage 40 is formed in the side wall of the trap 32 and an output passage 42 is formed on the end wall of the trap 34. It will be noted that the input passage 40 to and output passage 42 from chamber 44 are located at a higher level than are the

passages

36 and 38 formed in the

side walls

30 and 28, respectively, of the housing 12. By means of this arrangement of the

vapor traps

32 and 34 and of the input and

output passages

36 and 38, it is possible to ensure that liquid will not be transmitted from the chamber 44 in either (forward or rearward) direction except when it is nebulized into sufficiently fine particles to be carried by the gas as will become apparent. The lower edge of the housing 12 may be supported by a platform 18 and the housing is adapted to be mounted to prevent rotation by being secured to arms 21 (only one of which is shown in FIG. 1) which extend upwardly from the base plate 18 and are secured to the upright support 20.

The frame 14, housing 12 and

vapor traps

32, 34 may be formed from any suitable material such as plastic (polyethylene) or the like or they may be formed from a metal suitably protected against corrosion.

It will be seen from the foregoing description that the chamber 44 which is encompased within the housing 12 is generally cylindrically shaped-When the demand on the device is very high, chamber 44 may be filled with a substantial amount of liquid with the result that the lower portion of the chamber may and shall be referred to hereinafter as sump 46.

The drive shaft 48 which extends from 'the electric motor is connected by a suitable coupling 50 to the main drive shaft 52. As shown in FIG. 2 of the drawings, the main drive shaft 52 is mounted for rotation in the

side walls

28 and 30 of the housing 12. The shaft is suitably sealed relative to the

walls

28 and 30 to prevent liquid from leaking out of the housing. A pair of discs 56 are mounted on the shaft 52 for rotation therewith. The discs 50 are spaced apart on the shaft by coil spring 58. As will be apparent hereinafter, the discs are suitably constructed to nebulize the water within the chamber by their agitating action when they are rotated at high speed. FIG. 2 also serves to diagrammatically illustrate a body of water 60 located in the sump 46 of the housing. FIG. 2 also illustrates the location of the water input passage 62. It will be noted that this passage is arranged so as to discharge water into the chamber in close proximity to the disc 56. This ensures that water entering the chamber through feeding tube 64 will strike the blade 56 and this serves to further speed the nebulizing of the water when the blade 56 is rotating.

A typical flow path for the gas through the chamber 12 is diagrammatically illustrated in FIG. 3 of the drawings. In FIG. 3, a particular form of disc construction is illustrated. However, it will be understood from the description of FIGS 6 to 12 that various forms of disc may be employed. In the embodiment illustrated in FIG. 6, the disc 56 has semi-circular recesses at the peripheral edge and two circumferentially extending rows of

passages

72 and 74 spaced radially inwardly of the disc. Similarly, the disc 57 has peripheral edge recesses 70a and two rows of

passages

72a and 74a. Each of the

recesses

70 and 70a and

passages

72, 72a, 74 and 74a has a small inlet orifice and a large outlet orifice. In the discs illustrated in FIG. 3, each of the

notches

70, 70a has a small diameter on the upstream side of the disc 56 and on the downstream side of disc 57 respectively. The passageways 72 are likewise arranged such that the small orifice is alternately arranged on the upstream side and downstream side of each of the

discs

56 and 57. The passages 54a are all arranged with the smaller orifice disposed at the upstream face of the

discs

56 and 57 respectively. The path of flow of gas through the housing 12 is illustrated by the flow arrows shown in FIG. 3. The gas enters the trap 32 by way of the input passage 40 and passes through the trap to discharge into the housing to discharge into the housing through the passage 36. The gas travels through the housing to discharge through the outlet passage 38 into the trap 34. The humidified gas then discharges from the trap 34 by way of the output passageway 42. While the gas is in the chamber 44 and while the

discs

56 and 57 are rotated in the direction of the arrows A, the gas will tend to be drawn through the

various passages

70, 70a, 72, 72a, 74 and 74a in the direction from the high pressure areas to the low pressure areas. It has been found that by tapering the passages in the manner previously described and alternately arranging the direction of the taper in adjacent circumferential passages, it is possible to create a significant turbulence within the nebulizing chamber without creating any substantial back pressure which would inhibit the passage of gas through the device 10 (nebulizer). While it has been found that at slow speeds, the form and arrangement of the

passageways

70, 70a, 72, 72 a, 74,740 is not critical, nevertheless at high speeds it is desirable to provide a large number of said passageways through the

discs

56 and 57 in order to prevent the creation of a back pressure in the throughput line leading to and from the nebulizer 10 which would prevent the supply of an adequate amount of humid gas or vapor.

FIG. 4 of the drawings illustrates a form of apparatus which would be used to supply an anaesthetic gas to a patient. The gas is stored in a conventional storing device diagrammatically illustrated at in FIG. 4. Gas from the storage device 80 passes to a proportional control valve 82. The proportional control valve 82 is adapted to supply any predetermined proportion of the in-coming gas through input line 85 to the nebulizer device 10 and the by-pass line 84. The output from the nebulizer 10 passes by way of the line 86 to mingle with the gas in the by-pass line 84 and to pass to a facemask or other applicator device 88. Where a proportional control valve 82 is provided as shown in FIG. 4, it is possible to operate the nebulizer motor at a constant speed and to vary the degree of increase in relative humidity by adjusting the proportion of the gas flowing to the nebulizer in proportion to the gas by-passing the nebulizer.

A diagrammatic illustration of a section through a suitable proportion control valve 82 is shown in FIG. 5 wherein the valve housing 90 has an input passage 92 and output passages 94 communicating with the input line 85 and 95 communicating with the by-pass line 84. The valve body 98 which is rotatably mounted within the housing 90 has an intake chamber 100 and an associated output passage 102. In the position shown in FIG. 5, all of the drygas entering the valve by way of the passage 92 will be directed to the nebulizer through the

passages

102 and 94. To adjust the percentage of gas being directed to the nebulizer, the valve body 98 is rotated so that any required portion of the output passage 96 is opened to permit gas to flow into the by-pass line 84. It will be seen that the valve 82 may be rotated from the position shown in FIG. 5 to a position wherein all of the dry gas entering the valve may be discharged through the output passage 96 into by-pass line 94.

Referring to FIG. 6 a disc 110 which is suitable for use with a nebulizer of the present invention is illustrated in FIG. 6 of the drawings. The disc has a central opening 112 adapted to be fitted over the drive shaft 52 in a manner similar to the discs previously described. The disc 110 has a V-shaped groove 114 formed at the peripheral edge thereof. A plurality of small diameter passages 116 extend through the thickness of the disc and open into the lower end of the V-shaped groove 114. The passages 116 are located at uniformly spaced intervals at a predetermined radius from the axis of rotation. A second row of larger diameter passages 118 extend through the body of the disc and they are spaced radially inwardly from their passages 116. It has been found that a disc of this type may be used in the apparatus previously described to effectively nebulize water which is charged into or contained within the chamber 44.

An alternative disc structure is shown in FIG. 7 of the drawings. In this embodiment the disc 120 has two circumferentially spaced rows of through

passages

126 and 128 and a series of circumferentially spaced semicircular notches l24. Both the front face and back face of the disc are recessed adjacent to the notches 124 and

passages

126 and 128. Again, it has been found that a disc of this type will serve to nebulize water contained in or entering the chamber of the nebulizer when rotated at a sufficiently high speed.

FIG. 8 of the drawings illustrates a further form of disc 130 which has notches 134 and

passages

136 and 138, all circumferentially spaced relative to one another. In FIG. 8, all of the notches 134 and all of the

passages

136 and 138 have a tapered recess 139 formed in the front face 133 extending from front to back so that the opening at the back face of the disc is smaller than the opening at the front face of the disc.

In FIG. 9 of the drawings, the disc again has notches 144 at the peripheral edge thereof and

passages

146 and 148 disposed radially inwardly therefrom. In this embodiment, the notches 144 are alternately recessed on the front face and the back face. Similarly, the passages 146 alternately taper from the front face to the back face and from the back face to the front face.

All of the passages l48 decrease in diameter from the front face to the back face.

In FIG. 10 of the drawings, the notches 154 and the back face. The passages 166 and 168 are not tapered.

A simple form of disc is illustrated in FIG. 12. In this embodiment, the notches 164 and passages 176 and 178 extend straight through the body of the disc and they are not tapered in any way. I

Various additional modifications may be made to any of the discs. For example, an additional circumferentially spaced series of passages may be located radially inwardly of the innermost ring shown in FIGS.

- 9 through 12.

When this apparatus is used in medical or surgical applications, the dry gas, which may be any one of the well known anaesthetic gasses such as 0 He or anaesthetic agents as N or C0,, is delivered to the nebulizer by way of the proportional control valve 82. Water may either be charged into the sump 46 before the nebulizer is activated or it may be added continuously or in droplet form by way of an input passage 62. It will be understood that a combination of water stored in the sump and a continuous or drip supply may be used. When the motor 16 is activated, the

discs

56, 57, 110, 120, 130, 140, 150, 160, will be rotatably driven within the housing 44. A lower segment of each of the discs is adapted to pass through any liquid (water) 60, which is located in the sump 46. In this regard, it will be noted that only a very small clearance 49, is provided between the outer peripheral edge of the discs and the inner face of the cylindrical wall 26. It has been found that using any of the discs previously described it is possible to nebulize and transfer approximately 1.4 grams of water to oxygen passing through the chamber at a rate of 5 liters per minute when the chamber is initially filled with 20 grams of distilled water. Very similar results have been obtained with each of the disc structures illustrated in the drawings.

A plain disc (not shown) without any vent holes has been found to be capable of providing a relatively low increase in relative humidity. There may be advantage in the use of a plain disc structure in applications wherein it is desirable to provide an apparatus in which it is not possible or desirable to increase the relative humidity of a gas above the predetermined maximum. This structure is, however, not suitable for use when it is necessary to effect a higher rate of increase in relative humidity of gas. The plain disc does not permit a gas to pass freely through the chamber at a sufficiently high volume or speed nor does it provide the sufficiently effective milling action of the discs through the liquid 60 to increase the humidity of a large volume of gas passing through the chamber 44. The discs which are formed with the holes such as those illustrated in FIGS. 6 to 12 are capable of providing a substantial in crease in the relative humidity of a gas and of permitting a substantial flow of a gas through the chamber. It has been found that the conically shaped holes of FIGS. 7 through 10 act as a weak fan tending to increase the turbulence of the gas passing through the chamber 44 without substantially increasing the pressures within the milling chamber 44. This structure permits a very low fresh air (gas) circulation of the type commonly required in clinical .practice without the need to provide a subsidiary circulating fan. Thus the fluid between the disc and the chamber wall is sheared by the differential velocity of the fluid at these surfaces. This differential velocity is proportional to the rotating speed of the disc. The milling action thereby created has been found to cause molecules or minute droplets of fluid such as water to be dispersed into the atmosphere within the chamber and to be intermingled with the gas flowing therethrough.

It has been found that the amount ofliquid which can be put into a gas stream increases with the speed of rotation and the depth of liquid in the chamber.

It will also be noted that the input passage for the gas is located adjacent to the axis of rotation of the disc. When the disc is rotating the centrifugal forces at work within the chamber tend to cause a decrease in pressure in the area of the chamber adjacent the axis of rotation and consequently this action assists in the feeding of gas or air into the chamber.

A feature of the apparatus of the present invention which distinguishes it from the conventional room humidifiers is that the rotating disc action on the liquid within the chamber is in the form of a milling" action. It is this milling action which causes the mechanical rupture of the molecular binding forces in the fluid. The air or gas stream which passes through the chamber picks up the fine ruptured particles of the liquid and carries them away, thereby the relative humidity of the gas is increased very rapidly.

As previously indicated, it will be noted that only a very small clearance 49 is provided between inner cylindrical surface 26 of the chamber and the outer surface of the rotating disc. As a result, water which is located within the chamber will be picked up by the boundary layer adhesion and swept into motion and by centrifugal forces; the liquid will be thrown between the disc and the wall. The liquid 60 at the chamber wall 26 will tend to adhere to the chamber wall 26 while nearby liquid is dragged circumferentially by the disc; at the disc surface, the liquid tends to move at approximately the speed of the disc.

A number of tests have been carried out in order to illustrate the amount of liquid which can be nebulized by the embodiments of the present invention in a predetermined time period; In each of the first four tests two discs measuring 6 inches in diameter and one eighth of an inch in thickness were mounted on the shaft of the nebulizer and rotated at 1,640 r.p.m. therein. The peripheral edge was formed with 30 recesses of the type illustrated in FIG. 8. The first ring of passages were arranged one between each of the edge recesses and numbered thirty in all. The second row of passages were arranged between every second pair of passages in the first row and radially inwardly thereof and numbered 15 in all. The third row numbering 15 in all were located in a staggered relationship with respect to the second row.

TEST 1 The first test was carried out using 35 grams of distilled water in the sump and test results were measured after 10 minutes. Oxygen was passed through the device at a rate of 6 liters per minute and on an average of three such tests the amount of water picked up.by the oxygen was found to be 5.4 grams which expressed in mg/liter amounts to about 91 mg/liter. A further feature noted in these tests was that, whereas the ambient temperature of the input gas was 76 F, the output temperature of the gas from the nebulizer increased to 88 F.

TEST 2 A further test was carried out with a disc which had a small diameter (i.e., 1.705 inches) such that no contact was made with water in the sump 46. Oxygen, at a rate of 5 liters per minute was passed through the device 10 and at the beginning of the test the sump 46 contained 5 grams of distilled water. After a period of 10 minutes the amount of liquid picked up .by the oxygen was found to be 0.26 grams.

TEST 3 ln test three a disc of the type illustrated in FIG. 12 was rotated in the chamber in the range of 1,400 to 1,750 r.p.m. but precise measurementwas impossible. Oxygen was passed through the chamber at a rate of 5 liters per minute and 5 grams of distilled water was in the sump. After 10 minutes 1.26 grams of water was transferred to the oxygen.

The above,tests were repeated with various gases and the results of these are set out below in Table I.

TABLE I Gas Water Pick-up (mg/liter) wherein;

gas A comprises N 0 4 liters/min. O 2 liters/min. Flouthane 1% gas 13 comprises N 0 4 liters/min. O 2 liters/min. Penthrane 1% gas C comprised N 0 6 liters/min. A number of additional tests were carried out under the conditions set forth in Test 3 above and the results are given below in Table II.

TABLE II Test No. Blade (Fig) H2O Pick-up From these tests it will be apparent that the humidity of the oxygen can be considerably increased by passing it through the device of the present invention.

Referring to Test 1 it will be seen that the relative hu midity of the oxygen has been increased to about 400 percent. While charts showing the mass of water yapor in saturated oxygen are. not available it has been established that the saturation content of oxygen is substantially the same as that for air. Accordingly the relative humidity of the output of Test 1 has been determined as follows:

Relative Humidity (I000 W X 100/RTE) Where R Flow rate (liter/min.) T=Time (mins.) W= Moisture picked up (grams) E Mass of vapor in saturated oxygen at test temperature (76 F) Relative humidity of oxygen 10 X 5.4)][6 X 10 X (22.8)]bl approx. 400% By way of further explanation the relative humidity is determined generally according to the above formula. Where water vapor is in equilibrium over a body of water the relative humidity is said to be 100 percent. More particularly, however, the relative humidity is 100 percent at various temperatures and the amount of water vapor within any given gas can be determined from standard tables which are available in the art. Now the relative humidity of 100 percent is achieved at any given temperature when the air is quiet and when the body of water with which that air is in equilibrium is also quiet. Now if the water is made turbulent as by water being caused to be thrown off the surface of the body of water by a mechanical means,

the adjacent gas (air) is no longer quiet and becomes itself turbulent. The new turbulent equilibrium can be measured'as a relative humidity above the 100 percent (i.e., the relative humidity for quiet gas and liquid in equilibrium. In reality this new turbulent gas (air) liquid (water) equilibrium is supersaturated with individual molecules of liquid (water) vapor or an agglutination of such molecules, such agglutination either being visible or invisible to the naked eye. In the above tests the molecules of water vapor in the gas are invisible to the naked eye.

The above explanation of how one achieves a relative humidity in excess of 100 percent should not be taken to assume that any of the above tests in face does achieve an equilibrium between turbulent gas and water. What certainly is achieved is a relative humidity higher than would be achieved between quiet gas and liquid in equilibrium. Now referring to the invention further test results indicate that after 10 minutes of operation of 50 grams by weight of water placed in sump 46 and with a disc speed of 1,540 RPM and an oxygen gas flow at the rate of 6 liters/minute, 6.2 grams of water had been lost and hence 103.3 mg. of water had been dispersed into each liter of oxygen passing through the device 10. Throughout this test the vapor temperature was 73 F.

Referring to FIGS. 13 and 2a, further embodiments of the invention are illustrated. The nebulizer 10' has a series of fixed baffles disposed in close proximity to the

rotating discs

56 and 57. For example, the baffie may be in the form of lugs 200 projecting inwardly from the cylindrical walls of the chamber 44, particularly in the upper portion thereof (above the axis driveshaft 52 of rotation of the discs). Further, referring to FIGS. 1

and 2, an additional baffle may be disposed between the

discs

56 and 57 as by plug 27 which has a sufficient extent to project through the cylindrical 26 wall and into the space between the

discs

56 and 57. Preferably the baffles are to be located in close proximity to the rotating blades (discs), for example, one-eighth inch (3 mm.) so as to disrupt the flow of liquid adjacent the surfaces of the rotating discs. In this embodiment any of the discs disclosed in the FIGS. 3, 6, 7, 8, 9, 10, 11 and 12 may be used. I

These and other modifications of the present invention will be apparent to those skilled in the art without departing from the scope of the invention.

lclaim:

l. A device for controllably increasing the relative humidity of a gas comprising, a body having a chamber with a sump in the lower portion, means for admitting water opening into said sump, disc means in said chamber rotatable with a sector of its marginal edge in said sump, means for rotating said disc means at a speed which is sufficiently high to nebulize water within said chamber by the agitating action of the rotating disc means so as to increase the relative humidity of a gas passing through the chamber, said disc means extending substantially across the entire flow passage and having a plurality of apertures extending through the said body thereof and a plurality of substantially uniform recesses extending inwardly from the peripheral edge thereof at circumferentially spaced intervals to permit gas to flow from one side of said disc to the other by way of said apertures and recesses during rotation, inlet means opening into said chamber for admitting gas to said chamber and outlet means opening out of said chamber for withdrawing gas therefrom, said inlet and outlet means being disposed on opposite sides of said disc means.

2. A device as claimed in claim 1 wherein a first ring of uniformly circumferentially spaced apertures is spaced inwardly from the peripheral edge of said disc.

3. A device as claimed in claim 2 wherein each of said apertures has an inlet orifice at one face of said disc and an outlet orifice at the other face of said disc, inlet orifice being substantially smaller than said outlet orifice.

4. A device as claimed in claim 2 where a second ring of uniformly circumferentially spaced apertures is located radially inwardly of said first ring of apertures.

5. A device as claimed in claim 4 wherein the outer peripheral edge of said disc is formed with a segmented circumferentially extending V-shaped groove extending radially inwardly a distance sufficient to open into said first ring of apertures, said first ring of apertures being substantially smaller than said second ring of apertures.

6. A device as claimed in claim 4 wherein each of said apertures has an inlet orifice and an outlet orifice, the inlet orifices of the apertures arranged in said second ring all being disposed at one side of said disc and the outlet orifices being disposed at the other side of said disc, the inlet and outlet orifices of each adjacent aperture in said first ring of apertures being disposed on opposite sides of said disc whereby the flow of gas through one orifice in the first ring of orifices is in a direction opposite to the flow of gas through adjacent orifices in the first row of orifices.

7. A device as claimed in claim 6 wherein the outer peripheral edge of said disc is formed with a segmented circumferentially extending V-shaped groove extending radially inwardly a distance sufficient to open into said first ring of apertures, said first ring of apertures being substantially smaller than said second ring of apertures.

8. A device as claimed in claim 1 having at least two disc members mounted for rotation in said chamber about a common axis of rotation, said discs being arranged in a spaced parallel relationship.

9. A device as claimed in claim 1 including feed water control means for controlling the flow of feed water to said sump to thereby control the amount by which the relative humidity of the gas is increased and speed control means for controlling the rotational speed of said disc means to thereby control the increase in relative humidity of the gas passing through the chamber.

10. The device of claim l,wherein the rotating disc means is disposed essentially perpendicular to the gas flow.

11. A device as claimed in claim 10 having at least two disc members mounted for rotation in said chamber about a common axis of rotation, said discs being arranged in a spaced parallel relationship.

12. The device as claimed in claim 1 including baffle means and liquid trap means at said gas outlet means to prevent the passage of heavy particles of liquid from the chamber said baffle means extending to within close proximity of a rotating disc such that the flow of liquid adjacent to the surface of the rotating disc is disrupted.

13. A device as claimed in claim 12 wherein the baffle means extends to within 3 millimeters of the surface of a rotating disc.

- CERTIFICATE OF CORRECTION Patent No. 3,711,071 Dated an ary 16, 1973 j Nikodem N. Urbanowicz Inventor(s) v It is certified that error appears in the aboveddentified patent and that said Letters Patent are hereby corrected as shown below:

On the cover Sheet insert [73] Assignee: Air and Health Scientific Limited, Ontario, Canada Signed and sealed this 8th day of October 1974.

(SEAL) Attest: I

McCOY M. GIBSON JR. v C. MARSHALL DANN Attesting Officer Commissioner of Patents FORM po'wso (10'69) USCOMM-DC 60376-P69 U 5. GOVE RNMENT PRINTING OFFICE,

Claims

1. A device for controllably increasing the relative humidity of a gas comprising, a body having a chamber with a sump in the lower pOrtion, means for admitting water opening into said sump, disc means in said chamber rotatable with a sector of its marginal edge in said sump, means for rotating said disc means at a speed which is sufficiently high to nebulize water within said chamber by the agitating action of the rotating disc means so as to increase the relative humidity of a gas passing through the chamber, said disc means extending substantially across the entire flow passage and having a plurality of apertures extending through the said body thereof and a plurality of substantially uniform recesses extending inwardly from the peripheral edge thereof at circumferentially spaced intervals to permit gas to flow from one side of said disc to the other by way of said apertures and recesses during rotation, inlet means opening into said chamber for admitting gas to said chamber and outlet means opening out of said chamber for withdrawing gas therefrom, said inlet and outlet means being disposed on opposite sides of said disc means.

10. The device of claim 1, wherein the rotating disc means is disposed essentially perpendicular to the gas flow.