US2218597A - Air conditioning method and apparatus - Google Patents

Description

Oct. 1940- c. M. ASHLEY ETAL 2,218,597

AIR CONDITIONING METHOD AND APPARATUS Filed June 5, 1936 2 Sheets-Sheet 1 111g. 1. fi

INVENTORS CARLYLE M ASHLEY BY $4 5 SM Wi l/UV WNW Oct. 22, 1940. C M ASHLEY ETAL 2,2 55,5537

' AIR conmnomm METHOD AND APPARATUS Filed June 5, 1956 2 Sheets-Sheet 2- A TTORNE Y.

Patented Oct. 22, 194) UNITED STATES PATENT OFFICE Am CONDITIONING METHOD AND APPARATUS Carlyle M. Ashley, Summit, and Sam F. Shawhan,

Maplewood, N. J., assignors, by mesne assignments, to Carrier Corporation, Newark, N. 1., a e corporation of Delaware Application June 5, 1936; Serial No. 83,777

6 Claims.

hotel rooms, hospital rooms, school rooms, residences and the like, effectively and economically.

It is another object of the invention to provide an improved air conditioning unit for conditionlO ing and ventilating enclosures in which the moisture condensed by the cooling coils of the unit is utilized effectively to subcool liquid refrigerant prior to its supply to the evaporator coils. The evaporation of such condensate provides a highly 15 satisfactory solution for the problem of condensate disposal, and permits the elimination of drain pipes and the like which heretofore have rendered the installation of room cooling units time-consuming and expensive, and have im- 20 paired the mobility of the units. 7

Applicants unit is entirely self-contained and may be installed in a relatively short time with a minimum of effort. Installation is effected by providing a fresh air duct between the unit and 25 a source of outside air, such as an open window, and by plugging in an electrical connection from the unit to a source of electrical energy. The unit is adapted to be moved readily from one location to another with very little work, and with 30 practically no additional expense to the owner.

v Its portability renders the unit of particular advantage for on call service in such places as hotels, which cater to transients, and in meeting the requirements of short-term leaseholders.

35 The evaporation of condensate not only increases the mobility of the unit, but also increases its efiiciency through evaporative subcooling of the liquid refrigerant.

It is another object of the invention to provide 40 an air conditioning and ventilating system in which air drawn from the outdoor atmosphere is circulated over the compressor, condenser and subcooler of the system, and is then discharged to the outdoor atmosphere, and in which other 45 air drawn from the outdoor atmosphere and/or air drawn from the enclosure served by the system is circulated over the cooling coils of the system and is then discharged into the enclosure.

gardless of differences between. indoor and outdoor static pressures; and the low pressure fan circulates air over the compressor, condenser and subcooler of the unit.

A feature of the invention resides in the provision of a conditioning unit having a compressor, condenser, subcooler and evaporator, in which air drawn from the outdoor atmosphere and air drawn from the enclosure served by the unit are circulated over the coils of said evaporator, 10 whereby moisture is condensed therefrom, this moisture then being utilized to wet the heat exchange surfaces of said subcooler, other air drawn from the outside atmosphere being circulated over said condenser and said subcooler and then being exhausted to the outdoor atmosphere, whereby refrigerant is condensed in said condenser and evaporatively subcooled in said subcooler, and whereby the moisture condensedv from the air contacting said evaporator coils is cargo ried to the outside atmosphere in vaporous form. Another feature of the invention resides in the provision of an air conditioning unit including an evaporator, a condenser and a subcooler, moisture condensed from air contacting said evaporator being supplied to a pan within which the subcooler is disposed, water from said pan being sup-'- plied to the outer surfaces of said condenser whenever the level of water within the pan rises above a predetermined point. Such distribution of water over the condenser may be effected by a spinner carried on the shaft of a fan employed to circulate air over the subcooler and condenser. Another feature of the invention resides in the provision of an air conditioning and ventilating unit in which two motors are employed. The' first of these drives a high pressure fan used for supplying air to the enclosure served by the unit. The second motor serves to drive the compressor of the unit, a low pressure fan which circulates 40 outdoor air over the subcooler and condenser of the unit, and also a spinner for distributing water over the outer surfaces of the condenser whenever the heat dissipated in the subcooler is insufiicient to evaporate the moisture precipitated by the cooling coils of the unit.

Other objects, features and advantages of the invention will be more apparent from the following description to be read in connection with the accompanying drawings in which:

Fig. 1 is a front elevational view of applicant's unit with the front of the casing removed;

Fig. 2 is an end elevational view of the unit of Fig. 1;

Fig. 3 is a view taken on the line 3-3 of Fig; 1;

Mg. 4 is a view taken on the line 4-4 of Fig. 1;

and

Fig. 5 is a fragmentary plan view of the unit of Figs. 1 and 2, with a, portion of the cover broken away to show the duct which supplies air to the high pressure fan; and

Fig. 6 illustrates a modification of the invention.

Referring to the drawings, l0 designates generally the casing of an air conditioning unit having rearward section of the upper part of the unit serves as an air passageway. A duct l9 provides communication between the rear of the upper portion of the unit and a source of fresh air, such as an open window or the like, as disclosed in copending application, Serial No. 83,116 filed June 5, 1936. A'vertical partition 23 extending crosswise of the unit and having formed therein an opening in which the fan I! is disposed, divides the unit, as viewed from the front, into a left hand portion and a right hand portion, except that this partition does not extend through the upper forward portion of the unit in which the cooling coils are disposed. Fresh air duct I9 is arranged to communicate with both the left hand and right hand portions of the unit, and is preferably provided with a partition 24 which constitutes, in effect, a continuation of the partition 23.

Formed within the casing I8 is a vertical conduit 25 having proximate the top thereof an opening 26 and an opening 21. Duct 25 supplies air to a fan 28, driven by a motor 29 carried on supports 29a. Fan 28 is preferably of the high pressure type, so that it will draw in through the duct [9, opening 28, and duct 25 fresh air from the outdoor atmosphere, even when the static pressure of the outdoor atmosphere is relatively low. Air from the enclosure is supplied to the fan 28 through inlet grille I and the opening 21 in duct 25. By regulating the position of the hingedly mounted damper 30, associated with the openings 28 and 21, fresh air and air from the enclosure may be supplied to the fan 28 in desired proportions. Casing l8 prevents fan 28 from drawing in air through any other path than through duct 25.

Fan 28 discharges into a plenum chamber 3|, extending substantially throughout the length of the unit. The plenum chamber 3| is provided with a number of nozzles 32 for discharging air from the plenum at relatively high velocity in order to induce a relatively great secondary circulation of air withdrawn from the enclosure, through inlet grille H. In a preferred form of the invention, the nozzles 32 comprise flat, thin chambers, extending upwardly from the top of the plenum chamber and having a plurality of air discharge openings 33 formed therein. Preferably, the top of the nozzles 32 slopes downwardly toward the front of the unit. Any desired number of nozzles 32 may be provided lengthwise of the unit.

The air discharged through nozzles 32 at high velocity, induces a relatively great secondary circulation of air withdrawn, from room served by the unit through inlet grille Ii. This induced air passes over coils of evaporator 34 which are positioned just inside the inlet II, and is cooled and dehurnidifled thereby. Another part of the evaporator 34 is disposed within the plenum chamber 3|, preferably in the upper portion thereof, so that both the primary air discharged by fan 28 and the secondary air induced through inlet II are separately cooled prior to mixture in the mixing chamber 60. In a preferred form of the invention, refrigerant passes from expansion valve 35 through the rear portion of plenum chamber 3|, then through the coils adapted to cool the induced air, and then through the front portion of the plenum chamber 3|, whence it is passed to compressor l4 through suction line 35. Sound absorbing baiiles of any desired construction are preferably positioned in the lower portion of the plenum chamber to prevent the sounds .of fan 28 from reaching the enclosure served by the unit. The mixture of primary air and secondary air is supplied to the enclosure through outlet grille l2. If desired, guide vanes may be provided in chamber 80 for directing the air passing to the outlet grille in a slightly forward direction.

Refrigerant which has been compressed by compressor I4 is condensed in condenser l3 by fresh air drawn into the unit and circulated over the condenser |3 by fan ll. Condensing air entering the unit passes through inlet portion 31a of the duct l9 and is discharged to the outdoor atmosphere through the outlet portion 31b of the duct l9. As will be understood, this air also takes up heat from the compressor and its driving motor. Refrigerant liquefied in the condenser is supplied to liquid receiver 38 whence it passes to subcooling coil 39 disposed within the pan 48 in the bottom of the unit. subcooling coil 39 preferably comprises a considerable length of coil, to provide a relatively great heat exchange surface. If desired, refrigerant passing from the receiver 38 to the subcooler coil 39 may be routed through several lengths of coil, such as Na, in the air stream set up by fan H, to effect air subcooling -of the refrigerant. In a preferred form of the invention, however, evaporative subcooling is employed. Moisture condensed from the induced air is collected in pan 6|. Moisture condensed from the air in the plenum chamber is collected in a pan or the like and is delivered from the plenum chamber through a tube 82. Preferably, tube 82 is of small. diameter and is spiralled. Thus there is no appreciable loss in the pressure of the plenum; and due to the friction developed in the spiralled tube, the velocity of air passing from plenum chamber 3| through the tube 82 is so reduced that objectionable whistling is avoided. Moisture from pan 6| and tube 62 is delivered tocondensate tube 4| which discharges into the pan 40. Thus refrigerant in coil 39 is evaporatively subcooled by air discharged by fan I! and by the condensate supplied to the pan 40. The evaporative subcooling of liquid refrigerant provides a simple, yet highly effective, method of disposing of moisture precipitated by the cooling coils of the unit, which does away with the necessity for drain pipes or the like and increases the efliciency of the unit. Whenever moisture is precipitated by the cooling coils of the unit at a greater rate than moisture is condensate and further to increase the efiiclency of the unit, applicant provides a spinner "carried on the shaft driving fan l1. Spinner 42 may be of any desired construction, but preferably takes the form of a wire ring 63 adapted to be rotated through a number of spokes 64 connected to its driving shaft. Whenever the liquid level in pan 80 rises above a predetermined point, as for example the top of the subcooling coils, the spinner 42 splashes water from the pan. This water is carried to and distributed over the outer surfaces of the condenser l3 by the air stream set up by fan 11. Thus refrigerant in the condenser is evaporatively subcooled, increasing the efficiency of the unit, and the condensate precipitated by the coils is evaporated. Condensate in vaporous form is discharged to the outer atmosphere with air leaving the unit through out-' let portion 31b of the duct I9.

In the modification of the invention illustrated in Fig. 6, the propeller fan I1 is replaced by a centrifugal fan 90 within scroll or housing 9|. Housing 9! is mounted over, but relatively close to pan 40. An opening 92 is provided in'the fan scroll. When the liquid level in pan 40 rises, due to insufiicient evaporation of condensate by subcooler 39, water passes through opening 92 into the fan housing, where it is picked-up by the air stream of fan 90 and delivered to the condenser I3 through passage 93, whereby refrigerant in the condenser is evaporatively condensed and the moisture is evaporated. Although pressure will be developed within the fan scroll, such pressure will be overcome by hydrostatic pressure of condensate on the opening 92. Fan 99 may be driven in any desired manner, as by a separate motor or by motor 15, in the latter case, it being preferred to position the motor with its axis parallel to that of the fan 99. Applicants do not restrict the invention to any particular driving arrangement, and any desired gear, belt, or common-shaft arrangement may be used.

Since many modifications may be made in the invention without departing from its scope, applicants intend that the above description and accompanying drawings be considered as illustrative only, applicants limiting themselves only as indicated in the appended claims.

We claim:

1. The method of air conditioning an enclosure which consists in drawing outside air from the outdoor atmosphere, passing said outside air in heat exchange relation with a volatile refrigerant whereby said outside air is cooled and moisture is precipitated therefrom, discharging said outside air at high-velocity to induce a relatively great secondary circulation of air withdrawn from said enclosure, said withdrawn air being passed in heat exchange relation with a volatile refrigerant whereby said withdrawn air is cooled and moisture is precipitated therefrom, supplying said outside air and said withdrawn air to the enclosure, withdrawing other air from the outdoor atmosphere, passing said other air in heat exchange relation with said refrigerant to condense said refrigerant, passing said other air and said moisture precipitated from said outside air and said air withdrawn from the enclosure in heat exchange relation with the condensed refrigerant, and exhausting said other air to the outdoor atmosphere.

2. A method according to claim 1 in which moisture precipitated from the outside air and air withdrawn from the enclosure is placed in heat exchange relation with refrigerant being cooled by said other outdoor air, whereby said refrigerant is cooled and condensed by heat transfer with said other air and by the evap oration of said precipitated moisture, whenever moisture is precipitated from the outside air and air withdrawn from the enclosure at a greater rate than moisture is evaporated in the subcooling of condensed refrigerant.

3. The method of air conditioning an enclosure which consists in drawing outside air from the outdoor atmosphere, passing said outside air in heat exchange relation with a volatile refrigerant whereby said outside air is cooled and moisture is precipitated therefrom, discharging said outside air at high velocity to induce a relatively great secondary circulation of air withdrawn from said enclosure, supplying said outside air and said withdrawn air to the enclosure, withdrawing other air from the outdoor atmosphere, passing said other air in heat exchange relation with said refrigerant to condense said refrigerant, and passing said other air and said moisture precipitated from said outside air in heat exchange relation. with the condensed refrigerant.

4. The method of air conditioning an enclosure which consists in drawing outside air from the outdoor atmosphere, discharging said outside air at high velocity to induce a relatively great secondary circulation of air withdrawn from said enclosure, said withdrawn air being passed in heat exchange relation with a volatile refrigerant whereby said withdrawn air is cooled and moisture is precipitated therefrom, supplying said outside air and said withdrawn air to the enclosure, withdrawing other air from the outdoor atmosphere, passing said other air in heat exchange relation with said refrigerant to condense said refrigerant, and passing said other air and said moisture precipitated from said air withdrawn from the enclosure in heat exchange relation with the condensed refrigerant.

5. In an air conditioning unit, an evaporator,

'a condenser operatively associated with said evaporator and adapted to receive refrigerant therefrom, a receiver adapted to receive refrigerant .from said condenser, a subcooling coil adapted to receive refrigerant,- in liquid form substantially free of gas, from the receiver, means for delivering liquid refrigerant from the subcooling coil to the evaporator, means for circulating air in heat exchange relation with the evaporator, whereby said air is cooled and moisture is precipitated therefrom, means for supplying said cooled air to an enclosur'eserved by the unit, means for circulating other air in heat exchange relation with said condenser and a portion of said sub-cooling coil, and means for supplying said precipitated moisture to form a reservoir of liquid wherein another portion of the subcooling coil is located. a

6. In a unit of the character described, an evaporator, a condenser operatively associated with said evaporator and adapted to receive refrigerant from said evaporator, a receiver adapted to receive refrigerant from the condenser, a subcooling coil adapted to receive liquid refrigerant substantially free of gas from the receiver, means for delivering liquid refrigerant from the subcooling coil to the evaporator, means for circulating air in contact with the evaporator whereby said air is cooled and moistureis precipitated therefrom, means for supplying said cooled air to an enclosure served by the unit, 15

means for circulating air from outside said enclosure over said condenser and in heat exchange relation with said subcooling coil, means for supplying said precipitated moisture to form a liquid reservoir wherein at least a portion oi the cooling coil is positioned and means for supplying precipitated moisture over the outer surfaces of said condenser when the moisture in said reservoir rises above a predetermined minimum. CARLYLE M. ASHLEY. SAM F. SHAWHAN.

Images