US2282015A - Air conditioning unit - Google Patents

Description

May 5, 1942. a. s. WILLIAMS AIR CONDITIONING UNIT Filed Nov. 15, 1939 4 Sheefs-Sheet l NVENTOR may 5. .w'zzwmd a: n 11 p y 5, 1942- B. s. WILLIAMS 2,282,015

AIR CONDITIONING UNIT Filed Nov. 13, 1939 4 Sheets-Sheet 2 YMMV/2.757075%? 11v VENZOR 52:22: 6]] 5. l l zzlzazqs.

A T T ORNE Y May 5, 1942. a. s. WILLIAMS AIR CONDITIONING UNIT Filed Nov. 13, 1959 4 Sheets-Sheet 3 INVENTOR ,Bzzrai-ZZ 5. Mkl/idm It! o ATTORNEY y 5, 1942- B. s. WILLIAMS 3 9 AIR CONDITIONING UNIT Filed NOV. 13, 1939 4 Sheets-Sheet 4 A TTORNEYa Patented May 5, 1942 AIR CONDITIONING UNIT Burdeil S. Williams, Dayton, Ohio, minor to Chrysler Corporation, Detroit,

ration of Delaware Mich a corpo- Application November 13, 1939, Serial No. 303,965

3C1aims.

My present invention relates to air conditioning units, particularly units of the self-contained type comprising a mechanical refrigeration system contained in a unitary package adapted to be placed on a window ledge or in an opening in a building wall for air conditioning an individual room of small or medium size. In particular, the type of refrigerating system is that which utilizes an air cooled condenser so that the unit may be readily installed without the necessity of providing pipes for condenser cooling water," the air cooled condenser being so arranged as to be traversed by a stream of air from outside of the building which is ejected from the unit back into the outside atmosphere.

My improvements comprise means whereby the unit is adapted to condition the atmosphere of a room under a plurality of conditions. Thus the unit is designed to supply a large amount of outside air in the event that the outside air is mild and need not be cooled to a great extent, or to recirculate room air again and again through the air conditioning mechanism in case such a course should be desirable, or to supply a regulated mixture of room air and fresh air.

A' further improvement resides in the manner in which the conditioned air is projected into the room. It has been observed that the operation of units of small capacity may be thought to be unsatisfactory because the output of the unit is small and the velocity of the stream of conditioned air so slight that a room occupant located at a slight distance from the unit does not obtain the full benefits of air conditioning because he does not feel the movement of cooled air about him. Comfort conditioning is achieved through a combination of physical effects, 1. e., the humidity of the air is lowered so as to increase its ability to absorb moisture from the clothing and body of the room occupant, the temperature of the air is lowered so as to cause it to feel cool to the body, and airmovement is increased so as to cause rapid removal of moisture-saturated and warm air from the vicinity of the person. It is known that the greatest number of people feel the. greatest comfort over a long period of time if the atmosphere in which they are located is at a temperature of approximately 72 F. with a relative humidity of approximately 50% and is moving at a rate of approximately 25 feet per minute. These conditions can only be obtained and maintained throughout an enclosure by the use of large and expensive apparatus governed by complicated and expensive controls. If controls are sacrificed the conditions may be all-'55 proximately maintained by the use of large and expensive apparatus, but in no event can these results be obtained under all conditions throughout the entire room unless the apparatus has a maximum capacity far greater than that of the ordinary portable window unit of the character under consideration. Thus in the average ofllce or bedroom, the size of which ordinarily is such as to have a floor area of 150 sq. ft. or more, which usually has "at least two windows, which usually has one wall exposed to full sun load during at least a large portion of the day, and which usually has at least four poorly insulated interior surfaces, it is considered necessary in order to maintain optimum comfort conditions regardless of the outside atmospheric conditions to provide a unit having a capacity equivalent to the melting of one ton of ice in twenty-four hours. Unfortunately, a one-ton or larger unit, and most offlces require one and one-half tons, is of such size due to the large sizes of motors, blowers, coils, compressors, and other parts, that a window unit would prevent light from being admitted through a large proportion of at least one window, and

would be too heavy to balance on a window ledge,

so that such units are usually floor mounted, occupying a great deal of floor space which may be too valuable thus to occupy. In addition to these considerations, the cost of a one-ton or one and one-half ton unit is usually so great that most prospective purchasers refuse to pay the price. Accordingly, the small capacity window units of one-quarter, one-third, or one-half ton sizes have been offered as spot or zone of occupancy" coolers. These units usually have no automatic controls and the owner thereof is usually limited to the use of a manual control switch which is turned on in order to cause the unit to operate. Since there is no regulation of the capacity of the unit by altering the mechanical refrigerating ability thereof, the present invention is designed to provide means for regulating the output of the unit by altering the character of the air treated thereby.

Window units usually treat between C. F. M. and 250 C. F. M. of air. Such a small quantity of air, unless propelled as a jet of small cross-sectional area, does not have a great deal of initial velocity. A small jet of air is objectionable because of the high-pitched noises occasioned by high speed blower operation and is further objectionable because a person seated in front of the blower would have at least a part of his body subjected to a blast of intensely cooled air moving at a high velocity. Accordingly. a large, relatively slowly moving blower is best for small capacity units, and the blower had best be located so that all or at least a large proportion of the evaporator coil is in the path of the airejected from the blower so that there is a tendency on the part of the evaporator coil to reflect and reduce noises occasioned by the propeller tips beating the air. In order efficiently to condition the stream of air passing over the coil the air should be moved relatively slowly, and hence, due to its relatively slow initial movement. the conditioned air may not have suillcient velocity to move more than a few feet beyond the outlet of the unit. The resuit of such operation, in some oflices or other rooms, is to create a local condition adjacent the unit strikingly at variance with conditions in another portion of the zone of occupancy. It is obvious that a small capacity unit cannot entirely condition the complete enclosure; hence it must be possible for the conditioned air to reach as much of the zone of occupancy as possible before the temperature difference thereof is dissipated by removal of heat from other portions 'of the room air, before the moisture vapor thereof is increased by addition of moisture vapor thereto from other portions of the room, and before its velocity is entirely dissipated. It is also a rule of air conditioning that if the latent or sensible capacity of the air conditioning mechanism is less than necessary a compromise should be achieved by stepping up air movement slightly, this compromise being only permissible to a certain extent since air movement beyond a certain speed is annoying. It is an object of my invention to achieve such a compromise by increasing the volume of air moved and the initial velocity thereof without increasing the volume of air treated by the unit and the velocity thereof across the cooling surface. A unit such as I have devised causes the projection of dehumidified and cooled air to a greater proportion of the zone of occupancy than that heretofore possible by the most efficient, quiet, small-capacity unit within my knowledge.

The foregoing and other objects and advantages of my invention should be apparent from inspection of the following specification taken in connection with the accompanying drawings wherein like numerals refer to like parts throughout.

In the drawings,

Fig. 1 is a front view of a unit of my invention in position on a window ledge, parts of the unit being schematically represented;

Fig. 2 is a side view of the unit in position on a window ledge;

Fig. 3 is an enlarged top plan view with the top of the unit broken away in order to show operating mechanism; 7

Fig. 4 is a section taken substantially along line 4-4 of Fig. 3;

Fig. 5 is a sectional view taken substantially along line 55 of Fig. 3;

Fig. 6 is a partial top plan view, with the top broken away, of a modification of the evaporator portion of the unit showing separate blowers for accomplishing the purpose of the single blower set forth in the preferred embodiment;

Fig. '1 is a sectional view taken substantially along line 1-1 of Fig. 6;

Fig. 8 is a detail view of the housing and outlet of one of the blowers disclosed in the modification of Fig. 6

Fig. 9 is a detail view of the housing and outlet of the other blower disclosed in Fig. 6

Fig. 10 is a front elevation of the evaporator portion of another modified form of the invention;

Fig. 11 is a top plan view, with the top broken away, of the modified form of blower arrangement disclosed in Fig. 10; and a Fig. 12 is a sectional view taken substantially along line 12- of Fig. 11.

Referring to Figs. 1 to 5, inclusive, there is disclosed a self-contained window ledge air conditioning unit 20 which is adapted to rest upon the window ledge II and to be maintained thereon by suitable supporting means 22 fastened to the building, and by lowering the window sash 23 into retaining clamps 24 and 25 provided on the top of the unit. The unit is made narrow enough to fit most windows so that side wings 28 and 21 are usually necessary to block the remainder. of the opening between the window sill 2i and window sash 23.

As is usual in mechanical air conditioning the unit comprises a compressor which is driven by a motor 3|, the compressor forcing hot, compressed refrigerant through pipe 32 into a condensing coil 35 from which liquefied refrigerant is ejected into the liquid line 34 which leads to the-evaporator coil 55, from which the suction pipe 35 returns the expended refrigerant to the compressor. The motor, compressor and condenser, together with a blower 3'! for drawing a stream of air from the interior'and forcing it back to the exterior for the purpose of cooling the refrigerant in the condenser coil 33, are located in a condensing section which is separated from the evaporating section of the air conditioning unit by an insulated wall 38. Since the condenser blower faces outwardly, noises therefrom are not so objectionable and a high speed blower of the type disclosed may be used,

the blower being directly connected to the motor ii. A blower of the character disclosed includes a shroud 40 which, in the present disclosure, is used as part of a condensed moisture disposal mechanism as disclosed in the copending application of Jerry M. Gruitch, Ser. No. 304,018, filed concurrently herewith.

As disclosed in'the copending application of B. W. Jewell, Ser. No. 303,969, filed concurrently herewith, and now Patent No. 2,240,784, issued May 6, 1941. the evaporator blower may be driven by the motor II, but I prefer to use a separate, slow speed motor located in the evaporating compartment, the motor 45 being directly connected to a blower 45 of the multiblade type having an involute housing 41 and provided with a short outlet duct 48 extending toward the coil 35. The blower 46 is preferably relatively long and may comprise two blower units placed back to back or a single cylindrical member mounted upon a hub 50 and provided with two sets of blades as shown in the drawings. The motor 45 operates at very low speed so as to rotate the blower slowly thereby moving the air relatively slowly through the large outlet duct 48, without the creation of blower noises. The outlet duct 48 is preferably centrally located so as to direct air outwardly through at least the central half of the evaporator coil, leaving spaces at the ends of the coil through which room air may be drawn into the unit and into the blower wheel. Room air is thus treated twice. once while being drawnintotheunitandisainwhilebeingejected from the unit, therebyincreasing the cooling and dehumidifying efiect of the relatively narrow heat transfer surface.

In.order to provide for the admission of a certain amount of fresh air I provide a duct ll adjacent one side of the unit, the duct extending beyond the side wing 20 and being provided with a sliding panel It having an operating knob II by means of which the panel may be moved so as to completely open the fresh air inlet opening it at the end of the duct outside of the wing It or the room air inlet opening I. at the end of the duct inside of the wing 28, or so that the panel may be positioned to admit a certain proportion of room air and outside air as shown in Fig. 3. It is obvious that, regardless of the position of panel 58, the amount of air which may be-admitted to the evaporating section is unvariable so that the unit will always have a fixed inlet resistance.

In order to cause the treated air to be projected to a greater distance and at a higher velocity so as to reach a greater proportion of the zone of occupancy, I provide a high velocity duct 60 located beneath the evaporator coil as, the lower wall of the duct being formed as a continuation of the involute housing 41. The outlet of the high velocity duct 60 is preferably located beneath the lower edge of the coil 35 and is preferably so constructed and arranged as to direct a stream of high velocity air at an angle upwardly into the stream of air issuing i'ro'm'the coil 35. The high velocity air is produced by the blower 46, the output of the blower being divided by the splitter 6| pivotally mounted at 62 adjacent the bottom of the coil 35, but the stream of air moving through duct 60 does not encounter the resistance of the coil 35 as is the case with the air moving through the outlet 48, hence leaves the unit at a higher velocity than the air stream travelling through the coil. The more extensively treated air leaving the coil 35 ordinarily would tend to drop toward the floor at a distance of a few feet from the coil, but the stream of high velocity air from duct 60 tends to force the cold air away from the fioor and to commingle therewith so as to temper it, the tempered mixture travelling a greater distance into the room before dropping away from the breathing level of the zone of occupancy.

The splitter Si is preferably fixed to an operating shaft 63 which extends through the wall of the unit and is provided with a crank 84 and an operating knob 65' which may be locked in any suitable position of adjustment, so that the relative volume of the stream of air issuing through the high velocity duct" may be varied; and the initial direction of the air stream from duct 80 may be varied by moving the vane 61 in the end of the duct. One form of vane 81 which may be used has its ends fixed but is made of light sheet metal which may be deformed as desired.

A further function may be provided by opening exhaust door 68, which is located in the side of the unit opposite duct 55, the insulating partition 38 being located inwardly of the wing 21 so that door 68 affords communication between the room and the condensing compartment. As explained in the above-mentioned patent of Bernard W. Jewell, the opening of door 68 lessens the volume of air drawn into the condensing compartment through the condenser, but since was theeuhaustedair-iscolderthantheoutsideair tbecapacityoftheunitisnot Ireatlyaifected.

The modification disclosed in Figs. 6 to 9, inclusive,showsthatthesamepurposesmaybe accomplished, perhaps to an even greater extent, by the use of separate blower wheels II and H, the wheel II being housed in an involute casing II and the wheel ll being housed in an adjoining invoiute casing II, the two wheels, being mounted upon and driven by a single shaft extending from motor ll, and the shaft being supported in a bearing 14 mounted in the adjoining backs of the housings 12 and II. The blower ll takes air from the evaporating compartment, part of which may have come through the duct II and the other part of which may have come through the left side of the coil 8|, and forms a relatively slowly moving stream of air travelling through outlet 48 against the resistance of coil II. The blower ll takes air from the evaporating compartment and projects it into a plenum chamber ll located near the bottom of the evaporating compartment and having its opening in registry with a high-velocity duct It beneath the evaporator coil 35. It is to be noted that adjustment of the volume of high velocity air as well as its direction may be accomplished by ad-' justing the vane II. In all other respects the operation and functions of the modification dis closed in Figs. 6 to 9, inclusive, are similar to 3 those of the first described unit.

The modification disclosed in Figs. 10 to 12, inclusive, comprises separate blower wheels 10 and II housed in involute casings 12 and 13, respectively, and driven by the shaft of motor 45 which is supported in a bearing I4 as described with respect to the modification of Figs. 6 to 9, inclusive. The stream of intensely conditioned air is drawn from the evaporator compartment by blower Ill and is projected through outlet duct 48 and the coil 35, but in this modification the stream of less extensively conditioned air from blower II is projected into a short connecting duct which leads the air into a plenum chamber ll occupying the transverse space beneath the coil 35 and having a vertical riser 82 at one end thereof and a second vertical riser 83 at the other end thereof, the risers occupying the front corners of the unit adjacent the ends of the coil 35. The corners of the unit are preferably rounded so as to provide an inwardly curved front surface for the risers l2 and I3, and a vertical slot 84 is provided adjacent the right end of the coil it through which airmay be projected upwardly and inwardly across the stream of air issuing from the blower II, there being a similar slot 85 through which air may issue from the riser 83. The two streams of air issuing from slots 84 and 85 converge slightly toward the stream of air issuing from blower II and commingle therewith so as to form a tempered stream travelling a considerable distance away from the surface of the unit. It is to be noted that the arrangement illustrated in Figs. 10 and 13 shows the air from slot ll travelling in front of the left end of coil 35 through which room air is being drawn into the evaporator compartment so that a small proportion of the air stream from slot st may be drawn back into the evaporator compartment; but the largest amount of air drawn into the evaporator compartments through this portion of coil 38 will comprise warm room air arising from adjacent the fioor of the room.

I have illustrated and described several embodiments of the present invention but it should be obvious to those skilled in the art that the invention may assume other embodiments, both in general arrangement and detail. All such modifications as come within the scope of the following claims vention.

Iclaim:

1. An air conditioning unit comprising cooling and dehumidifying means for treating the air, blower means in said unit for moving air into said unit in heat transferring relation to part of said cooling and dehumidifying means, said blower means including an outlet adjacent the. re-

mainder of said cooling and dehumidifying means whereby at least a part-of the output of said blower means traverses said remainder of said cooling and dehumidifying means, and a relatively unobstructed duct communicating with said outlet and extending to a point adjacent the outlet side of said cooling and dehumidifying means whereby a proportion of the output of said blower means is directed into the room adjacent the stream of air issuing from said cooling and dehumidifying means, said duct being arranged beneath said cooling and dehumidifying means and having relatively large width in comparison to its depth whereby to project a horizontal blanket of air beneath the air issuing from said cooling and dehumidifying means and said duct being directed slightly upward whereby to project said blanket of air into the air issuing from said cooling and dehumidifying means.

2. An air conditioning unit comprising cooling and dehumidifying means for treating the air, blower means in said unit for moving air into said unit in heat transferring relation to part of said cooling and dehumidifying means, said blower means including an outlet adjacent the remainder of said cooling and dehurnidifying means whereby at least a part of the output of said'blower means traverses said "remainder of said cooling and dehumidifying means, a relaare considered part of my in-v anaaoit tively unobstructed duct communicating with said outlet and extending to a point adjacent the outlet side of said coolingand dehumidifying means whereby a proportion of the output of said blower means is directed into the room adjacent the stream of air issuing from said cooling and dehumidifying means,- said duct being arranged beneath said cooling and dehumidifying means and having relatively large width in comparison to its depth whereby to project a horizontal. blanket of air beneath the air issuing from said cooling and dehumidifying means and said duct being directed slightly upward whereby to project said blanket of air into the air issuing from said cooling and dehumidifying means, and an adjustable directing vane mounted in the outlet end of said duct.

3. An air conditioning unit comprising a cooling and dehumidifying coil for conditioning the air, blower means in said unit having the inlet thereof so arranged as to cause air to be drawn through part of said coil to be initially cooled and dehumidified thereby, and the outlet thereof so constructed and arranged with respect to said coil as to direct a part of said initially cooled and dehumidiiled air through the remainder of said coil to be intensely cooled and dehumidified thereby, and to direct the remainder of said initially cooled and dehumidiiled air around said coil, said outlet comprising a large duct across which said remainder of said coil extends whereby said intensely cooled and dehumidifled air is projected at a relatively low velocity, said outlet also comprising a small unobstructed duct through which the remainder of the initially cooled and dehumidified air is projected at a relatively high velocity, said small duct being arranged to project air therefrom in a direction to converge with and commingle with the intensely cooled and dehumidified air emerging from said larger duct.

BURDELL S. WILLIAMS.

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