US2917905A

US2917905A - Self-contained air conditioning units of the room cooler type

Info

Publication number: US2917905A
Application number: US402260A
Authority: US
Inventors: William L Mcgrath; Francis D Stevens
Original assignee: Carrier Corp
Current assignee: Carrier Corp
Priority date: 1954-01-05
Filing date: 1954-01-05
Publication date: 1959-12-22
Anticipated expiration: 1976-12-22

Description

Dec. 22, 1959 w. L. M GRATH ETAL 2,917,905

SELF-CONTAINED AIR CONDITIONING UNITS OF THE ROOM COOLER TYPE Fi'led Jan. 5, 1954 s Sheets-Sheet 1 1 r H 4% FIG.| 1 4 H INVENTOR. 3! WM 4, lauzz,

Dec. 22, 1959 w, McGRATH ETAL 2,917,905

SELF-CONTAINED AIR CONDITIONING UNITS OF THE ROOM COOLER TYPE Filed Jan. 5, 1954 s Sheets-Sheet 2 v I INVENTOR.

Z- ZQGM y a M Dec. 22, 1959 w. MCGRATH ET AL 2,917,905

SELF-CONTAINED AIR CONDITIONING UNITS OF THE ROOM COOLER TYPE Filed Jan. 5, 1954 3 Sheets-Sheet 3 FIG.4

36 FIG.5

United States Patent SELF-CONTAINED AIR CONDITIONING UNITS OF THE ROOM COOLER TYPE William L. McGrath and Francis D. Stevens, Syracuse, N.Y., assignors to Carrier Corporation, Syracuse, N.Y., a corporation of Delaware Application January 5, 1954, Serial No. 402,260

'5 Claims. (Cl. 62-183) This invention relates to self-contained air conditioning units, such as room coolers and, more particularly, to a unit of this type which may be placed Within a building opening such as a window frame extending for substantially its length, if desired, without the opening to present a so-called hide-away appearance of the unit within a room being treated.

Conditioners of this general type heretofore have been designed in such manner that the cooling portion of the unit extends within the room being treated while the heat removal or condensing portion of the unit extends without the room being treated. Frequently, such units do not harmonize with the decorative scheme of the room so that a unit imparts an incongruous appearance to the room. This is necessarily so since as a commercial matter, it is impossible to provide a color scheme for the units which will harmonize with all decorative schemes; additionally, the fact that such a large portion of the unit necessarily protrudes within the room from a window frame detracts from or destroys the desired appearance of the room.

The chief object of the present invention is to provide a selfcontained air conditioning unit of the room cooler type in which substantially the entire unit may be disposed exteriorly of the room extending from the window opening so that the decorative scheme of the room to be treated is not marred by the incongruous appearance of the unit.

An object of the invention is to provide a self-contained air conditioning unit of the room cooler type in which the casing of the unit is so designed that a desired portion of the complete unit may extend without or within the room in accordance with the requirements of the installation.

A further object is to provide a self-contained air conditioning unit of the room cooler type in which room air to be cooled is passed a plurality of times through the heat exchange member of the unit thus providing more satisfactory cooling and dehumidification of such air.

A still further object is to provide simple control mechanism for units of this type which prevents formation of frost on the heat exchange member which may interfere with the capacity of the unit.

This invention relates to an air conditioning unit of the room cooler type which comprises, in combination, a substantially U-shaped base member forming the bottom and opposite sides of the unit, a partition extending across the unit from one side of the base member to the opposite side of the base member to divide the unit into a first compartment and a second compartment, a refrigeration system placed on said base member including an evaporator and a condenser, the evaporator being placed in the first compartment and the condenser being placed in the second compartment and forming, in effect, the rear wall of the unit, a cover fitting over the sides of the base member, means for passing air through the evaporator to cool the same and means for passing air through the 2,917,905 Patented Dec. 22, 1959 condenser to condense refrigerant of the refrigeration system.

This invention further relates to an air conditioning unit of the room cooler type which comprises, in combination, an enclosure, a partition extending across the enclosure from one side to the opposite side to form the enclosure into a first compartment and a second compartment, a refrigeration system in said unit including an evaporator and a condenser, the evaporator being placed in the first compartment and the condenser being placed in the second compartment and forming, in effect, the rear wall of the enclosure, means for drawing air through one portion of the evaporator to cool the same and for passing the cooled air through a second portion of the evaporator to further cool the same and means for drawing air through one portion of the condenser and for passing the same air through a second portion of the condenser to remove the heat absorbed by the refrigeration system.

This invention further relates to a method of operation of a room cooling unit in which the steps consist in passing a first air stream through one side of a coil forming the evaporator of a refrigeration system to reduce its dry bulb temperature, reversing the direction of flow of the cooled air stream and passing the same through the other side of the coil to further reduce its temperature, discharging the cooled air into the room to be treated and carrying away the heat removed from the first air stream by passing a second air stream in heat exchange relation with refrigerant in the condenser of the refrigeration system.

The attached drawings illustrate preferred embodiments of our invention, in which Figure 1 is an isometric view of the self-contained air conditioning unit of the present invention disposed in a desired position within a building opening such as a window frame;

Figure 2 is a plan view of the unit shown in Figure 1 with its cover and grille removed;

Figure 3 is an isometric view of the base member of the unit, illustrating a modification in the manner in which the evaporator fan is placed in the unit;

Figure 4 is a sectional view of the unit illustrating simple control mechanism to prevent frosting of the evaporator coil; and

Figure 5 is a view in elevation illustrating the condenser fin coil construction.

Referring to the drawings, there is disclosed the air conditioning unit 2 of the room cooler type disposed in place in a building opening as formed, for example, by the window frame 3. It will be appreciated that any desired portion of the unit may extend exteriorly of the opening to present a so-called hide-away appearance within the room being treated. A picture-frame gasket of the ring type (not shown) is placed around the unit. Wing panels 4- are placed between the unit and opposite sides of the frame 3 to close the space therebetween. The Window 5 is then moved downward to compress the gasket so as to complete the seal about the unit when it is disposed in desired position.

The manner of installation of the unit is shown and claimed in our copending application, Serial No. 402,364, filed January 5, 1954, to which reference is made for a more complete description of the manner of installation of the unit.

Unit 2 includes a box-like casing 6 formed of a U-shaped base member 7 forming the bottom 8 and

sides

9, 10 of the unit, a cover 11 which fits over the

sides

9, 10, and a grille member 12 which fits over the front of the unit. Grille member 12 is provided with inlets 13 and outlets 14 as hereinafter described. This construction provides a casing which may be placed in any suitable position within the building opening and does not 3 require that any specific length of the unit extend within the room being treated. Thus, a ring-like gasket may be applied about the unit in different positions to seal the unit when it is disposed in place in a building structure.

A partition 15 extends substantially from side to side of the unit and from the cover to the bottom to separate the unit into a first compartment 16 and a second compartment 17. An opening 18 is formed within partition 15 and is closed by a damper or bafile member 19 for a purpose hereinafter explained. Baffle 19 may be moved by suitable mechanism 20 to a first position, shown in dotted outline in Figure 2, to permit air to flow from compartment 17 through opening 18 into compartment 16, and may be returned to its initial position by releasing such mechanism to permit spring 21 connected between bafile 19 and an arm 22 attached to partition 15 or to the casing to return the baffle to initial position. If desired, suitable sealing material (not shown) may be placed about the opening or on the bafile to assure that a substantial volume of air does not leak into compartment 16 when the opening is closed.

To cool air drawn into the unit, a refrigeration system designated generally at 25 is provided. The refrigeration system 25 includes a compressor 26 driven by a motor 27 connected to a suitable source of electrical energy; preferably, compressor 26 and motor 27 are combined in a hermetic or semi-hermetic unit. Compressor 26 is connected to a condenser 28 which extends, preferably from side to side of U-shaped base member 7 and in effect forms the rear wall of casing 6. Preferably, condenser 28 is a plate fin coil, well known in the industry. Condenser 28 is connected to evaporator 29, a capillary tube (not shown) regulating flow of refrigerant from the condenser to the evaporator. Evaporator 29 is placed in compartment 16 and extends, preferably, from side to side of member 7. The evaporator 29 is connected to compressor 26 to return evaporated refrigerant to the compressor, an accumulator 30 being placed in the circuit between evaporator 29 and compressor 26 to prevent unevaporated refrigerant from returning to the compressor.

As shown in Figure 2, a fan compartment 31 is formed within compartment 16 adjacent the evaporator coil 29. Fan 32 is placed within the compartment and serves to draw room air through inlets 13 of grille 12 and one portion 33 of the evaporator 29 to cool the same and to pass the cooled air through a second portion 34 of evaporator 29 to further cool the same, discharging the cooled air through outlets 14 of grille 12 into the room being treated.

A fan compartment 35 is placed in compartment 17 adjacent the condenser coil 28, fan 36 being placed in such compartment. Fan 36 draws air from the exterior of the building through a first portion 37 of condenser 28 over the compressor and motor to cool the compressor and motor and then discharges the air through a second portion 38 of the condenser 28 exteriorly of the building. Passage of air through the condenser condenses the gaseous refrigerant and removes the heat from the system absorbed by refrigerant in the evaporator from the room air. If desired, a bafile (not shown) may be placed to extend rearwardly from the condenser to assure that the heated air after passage through the condenser is not drawn immediately into the first condenser portion 37. Preferably, however, the exterior edge portions 80 of the plate fins 81 of condenser coil 28 are bent at an angle, as shown in Figure 5, to prevent heated air being drawn into the condenser. Fins in condenser portion 37 are bent toward the outer edge of the coil while the fins in condenser portion 38 are bent in the opposite direction.

Fans

32 and 36 may be actuated by motor 39 connected to the source of electrical supply. If desired, however, these fans may, of course, be actuated by separate motors.

It should be noted that when baffle 19 is opened to its full extent, it abuts evaporator fan compartment 31 permitting fan 32 to draw air from compartment 17 for ventilation within the room being treated and preventing the plural passes of air through the evaporator coil.

When the unit 2 is installed in position in a building, preferably, it is tilted or pitched to permit condensate collected by the evaporator to pass into the condenser compartment and collect in a sump (not. shown). A slinger (not shown) is provided to fling the condensate into the air passing over the condenser and on the condenser coil thus evaporating the condensate to remove collected moisture from the unit. Openings 40 may be provided in partition 15 to permit the condensate to flow from compartment 16 to compartment 17. Porous, sponge-like absorbent members 41 are placed in openings 40 to prevent too rapid flow of condensate accumulated under certain conditions. Thus, the amount of condensate accumulated in compartment 17 is never so great as to overflow the unit, all condensate collected being dissipated or evaporated in the heated air stream discharged from the unit.

Considering the operation of the unit 2, fan 32 draws room air through inlets 13 in grille 12, through the first portion 33 of the evaporator 29 in heat exchange relation with refrigerant therein to cool the air and then pass the cooled air stream through the second portion 34 of the evaporator in heat exchange relation with refrigerant therein to further cool the air, the cooled air being discharged into the room through outlets 14 in grille 12. The evaporated refrigerant is condensed in condenser 28, fan 36 drawing outside air through portion 37 of the condenser and then passing the condensed air through the second portion 38 of the condenser.

When it is desired to provide ventilation air for the room being treated, damper or bafile 19 is opened to a desired extent thus permitting fan 32 to mix a stream of air from compartment 17 with air being drawn through portion 33 of evaporator 29. It will be appreciated the volume of the air stream drawn from the room through evaporator portion 33 is reduced when the damper 19 is opened since the open damper in effect blocks 05 a portion of such air stream in accordance with the manner in which it is opened so that the volume of cooled air discharged into the room remains substantially constant. If the damper is opened to its full extent, it abuts against fan compartment 31 thus effectively preventing passage of room air through evaporator portion 33. This is particularly desirable when ventilation air only is being supplied by operation of fan 32, it not being desired to cool such air so that the refrigeration system is not in operation.

In Figure 3, I have shown a somewhat different arrangement of the evaporator fan. In this case fan compartment 45 is placed centrally of the evaporator coil 29, fan 47 being placed therein to draw room air through the two

opposite sides

48, 49 of coil 29 and passing such air through the central portion 50 of the coil to discharge the same into the room being treated. In this case, the damper 19 abuts one side of compartment 45 when fully open, permitting fan 47 to continue to draw a desired stream of room air into the unit for admixture with the stream of ventilation air before discharge of the mixed streams into the room.

In Figure 4, I have illustrated the unit provided with simple control mechanism to prevent frosting of the evaporator coil. A control 55 reactant to existence of frost in the evaporator coil is provided. Such control may be a thermostat responsive to the temperature of evaporator coil 29 which is connected to the motor 56 of condenser fan 57. Preferably, the thermostat is placed on the evaporator coil within the air stream being directed through the evaporator 29, although if desired, it may be placed in any other suitable location, such as the suction line, liquid supply line, etc. Thermostat 55 is so designed that it discontinues operation of the condenser fan 57 at a desired evaporator coil temperature, say 26 F., and permits resumption of fan operation at a desired higher coil temperature, say 40 F., thus preventing frosting of the coil by cycling the condenser fan. Since the thermostat 55 is placed within the air stream being directed through the evaporator, the air passing thereover when the condenser is inoperative warms the thermostat thus accelerating resumption of operation of the condenser fan. This control mechanism avoids undesirable short cycling of the compressor for the compressor continues in operation even though the condenser fan is shut off. An inexpensive thermostat may be employed.

If desired, the inlets in the grille 12 may be formed in the bottom of the grille and outlets may be formed in the top of the grille. Such construction, of course, may require rearrangement of the position of the fan.

The present invention provides an air conditioning unit of the room cooler type so designed as to permit a desired portion of its length to be placed without a building structure. The unit is simple and inexpensive in construction and permits rapid and ready installation in desired position. After installation, the unit may be easily removed to permit window cleaning or for storage purposes, if it is not desired to use the unit in winter operation for ventilating purposes.

The unit provides more satisfactory cooling and dehumidification of room air since the air stream passes through the evaporator coil a plurality of times thus reducing the bypass factor. Simple control mechanism may be provided to control room temperature and to prevent frosting of the evaporator coil or ready removal of collected frost from the evaporator coil. Means are provided to prevent condensate overflowing the unit when conditions of excessive humidity are encountered. An advantage of the condenser design resides in the fact that leaves are not drawn into the unit while the closed casing structure prevents birds nesting within the unit.

While we have described a preferred embodiment of our invention, it will be understood that our invention is not limited thereto since it may be otherwise embodied within the scope of the following claims.

We claim:

1. In an air conditioning unit, the combination of a substantially U-shaped base member forming the bottom and opposite sides of the unit, a partition extending across the unit from one side of the base member to the opposite side of the base member to divide the unit into a first compartment and a second compartment, a refrigeration system placed on said base member including an evaporator and a condenser, the evaporator being placed in the first compartment and the condenser being placed in the second compartment and forming, in effect, the rear wall of the unit, a cover fitting over the sides of the base member, means for passing air through the evaporator to cool the same, means for passing air through the condenser to condense refrigerant of the refrigeration system, said partition having an opening therein adjacent to the base member, and a porous, absorbent, sponge-like member placed in said opening to regulate flow of condensate from the evaporator compartment to the condenser compartment.

2. In an air conditioning unit, the combination of an enclosure, a partition forming the enclosure into a first compartment and a second compartment, a refrigeration system placed in said enclosure including an evaporator, a compressor and a condenser, a prime mover for the compressor, the evaporator being placed in the first compartment and the condenser in the second compartment, means to direct a first air stream through the evaporator, a fan to direct a second air stream through the condenser, a motor to operate said fan and a control responsive to evaporator temperature to actuate said condenser fan, said control in response to a predetermined evaporator temperature discontinuing operation of said fan while operation of the prime mover continues to prevent substantial frosting of the evaporator and in response to a. second predetermined evaporator temperature again actuating the fan to direct the second air stream through the condenser.

3. An air conditioning unit according to claim 2 in which the control is placed in the path of the first air stream thereby expediting actuation of the fan.

4. In an air conditioning unit, the combination of a substantially U-shaped base member forming the bottom and opposite sides of the unit, a partition extending across the unit from one side of the base member to the opposite side of the base member to divide the unit into a first compartment and a second compartment, a refrigeration system placed on said base member including an evaporator, a compressor, and a condenser, and means for actuating the compressor, the evaporator being placed in the first compartment and the condenser being placed in the second compartment and forming, in effect, the rear Wall of the unit, a cover fitting over the sides of the base member, means to direct a first air stream through the evaporator, a fan to direct a second air stream through the condenser, a motor to operate said fan, and a control responsive to evaporator temperature to actuate said motor, said control in response to a predetermined evaporator temperature discontinuing operation of said fan while actuation of the compressor is continued to prevent substantial frosting of the evaporator and in response to a second predetermined evaporator temperature again actuating the fan to direct the second air stream through the condenser.

5. In an air conditioning unit, the combination of a substantially U-shaped base member forming the bottom and opposite sides of the unit, a partition extending across the unit from one side of the base to the opposite side to divide the unit into a first compartment and a second compartment, a cover fitting over the sides of the base member, a refrigeration system placed on the base member including an evaporator, a compressor, and a condenser, means for actuating the compressor, the evaporator being placed in the first compartment and extending substantially from side to side of the base member, the condenser being placed in the second compartment and forming, in effect, the rear wall of the unit, means for drawing a first air stream through one portion of the evaporator to cool the same and for reversing the direction of flow of the first air stream to pass the cooled air through a second portion of the evaporator to further cool the same, a fan to direct a second air stream through the condenser, a motor to operate said fan, and a control responsive to evaporator temperature to actuate said motor, said control, in response to a predetermined evaporator temperature, discontinuing operation of the fan while actuation of the compressor is continued to prevent substantial frosting of the evaporator and in response to a second predetermined evaporator temperature again actuating the fan to direct the second air stream through the condenser.

References Cited in the file of this patent UNITED STATES PATENTS 2,001,309 Kelly May 14, 1935 2,128,090 Hintze Aug. 23, 1938 2,240,784 Jewell May 6, 1941 2,278,989 Gruitch Apr. 7, 1942 2,282,015 Williams May 5, 1942 2,299,527 Cody Oct. 20, 1942 2,316,704 Moore Apr. 13, 1943 2,332,730 Kucher Oct. 26, 1943 2,390,182 Schirrmeister Dec. 4, 1945 2,457,851 Taft Jan. 4, 1949 2,526,391 Morgan Oct. 17, 1950