US2169900A

US2169900A - Air conditioning system

Info

Publication number: US2169900A
Application number: US714432A
Authority: US
Inventors: Lawrence A Philipp
Original assignee: Nash Kelvinator Corp
Current assignee: American Motors Corp
Priority date: 1934-03-07
Filing date: 1934-03-07
Publication date: 1939-08-15
Anticipated expiration: 1956-08-15

Description

g- 1 L. A. PHILIPP 2,159,900

AIR CONDITIONING SYSTEM Original Filed March 7, 1934 INVENTOR. 4 9mg P 1412 2 w BY -Patent e'd Aug.15,1939

mesne assignments, to Nash-Kelvinator Corporation, Detroit, Mich., a corporation of Maryland Application March 7, 1934, Serial No. 714,432

, Renewed January 11, 1939 10 Claims.

The present invention relates to air conditioning systems and particulai'ly to systems for cooling and dehumidifyingair, and is based upon the subject matter disclosed and claimed in my copending applications, Serial Nos. 697,169, 697,170, 697 ,171 and 697,172 filed respectively on November 8, 1933.

One of the objects of the present invention, is to provide a heat absorber over or about which 10 air is circulated which heat absorber, at times,

is maintained at such low temperature as to cool the air to considerably below the dew point thereof for the purpose of removing moisture from the air, to provide another heat absorber which, whenever it is in operation, operates constantly independently of the first heat absorber and which is utilized for removing principally sensible heat from air flowing over or about the same, and to provide for controlling the amount of heat removed by the heat absorbers in accordance with the condition of the air; in carrying out the foregoing object, it is a further object to control the system in accordance withthe'relative humidity and the temperature of the air.

25 Further objects and advantages will be apparent from the following description, reference being had to the accompanying drawing wherein a preferred form of embodiment of the present invention is clearly shown.

30 The figure in the drawing represents diagrammatically an air conditioning system.

The air conditioning system is herein shown, for illustrative purposes, for cooling a room such as a living room or an office and the room 20, and

35 the roqm is diagrammatically illustrated by a side wall 2|.and a floor 22. Within this room there is disposed a cabinet 23 having compartments 24 and 25. A partition 26 depends from the top wall 31 of the cabinet and extends from 40 the front to the rear thereof to divide said cabinet a 23 into the compartments 24 and 25. Air enters the compartment 24 and is expelled from compartment 25 through openings 29 and 30 respectively in the top-2l. Air is forced through the 45 cabinet by the fan 3| which is driven by a constantly operating motor 32. 1

A heat absorber 34, having fins 36 thereon for increasing the heat absorbing area thereof, is disposed within compartment 24 and is herein shown, for the purpose of illustrating one form of the invention, as an evaporator. Gaseous refrigerant is withdrawn from the evaporator 34 through a pipe 35 by the cylinder 31 of a compressor 38. The compressed refrigerant is deliv- 56. ered to a condenser 33 wherein it is cooled and known in the art as a thermostatically controlled expansion valve and such valve is shown in the Marshall Patent No. 630,617 and is employed as shown in the Marshall Patent No. 1,003,283. For the purpose of subjecting the expansion valve to the temperature at the outlet of the evaporator, a bulb 46 is intimately connected to the suction pipe 35 and is connected by a pipe 48 to theback side of the flexible wall of the valve 44. The bulb 46 and the pipe 48 contain a volatile fluid to affect the operation of the valve 44 so that it will operate also in accordance with changes in temperature of the outlet of the evaporator.

The operation of the compressor 38 will cause a loweringof the pressure and likewise a loweringof the temperature of the evaporator 34 and air flowing over evaporator 34 will be cooled. The size of the compressor is computed relative to the size of the evaporator so that during normal operation, only or principally sensible heat will be removed from the air as it flows over evaporator 34.

A second heat absorber 50 is also disposed within compartment 24 and is shown as an evaporator having fins 5| for increasing the heat absorbing surface thereof. Gaseous; refrigerant is withdrawn from evaporator 50 by a pipe 52 which pipe is connected through a valve 53, coupling 55 and pipe 51 to the low pressure side of a cylinder 58 of compressor 38. The condensed 40 refrigerant is cooled by the condenser 39 and the liquid refrigerant is conducted from the receiver 40 through the pipe 4| coupling 42 and a branch pipe 60 to an expansion valve 6|. This expansion valve may be of the same type as 45 valve 44 and is responsive to the pressure within the evaporator and the temperature at the outlet of the evaporator, it also being provided ,with a bulb 46 and a connecting pipe 43. The

capacity of the cylinder 58 is computed relative 50 to the size of evaporator 50 so that when the valve 53 is open, the pressure within theevaporator 50 is decreased to such an extent that the evaporator will cool the air flowing thereover to considerably below the dew point thereof,

ing the precipitation of moisture from the air to reduce the relative humidity thereof. The water will drip from the evaporator to the bottom of the cabinet 23 and will be drained therefrom through the drain pipe 63.

A restriction bypasses the valve 53 and is herein shown as a restricting pipe 64 which is connected between pipe 52 and coupling 55. When the valve 53 is closed, the restriction 64 permits a restricted flow of gaseous refrigerant from the evaporator 58 to the compressor 38 and the arrangement is such that when valve 53 is closed, the quantity of gaseous refrigerant withdrawn from evaporator 50 is sufficient only to cause the evaporator 50 to be lowered in temperature to remove only or principally sensible heat from the air.

The desired temperature of the air is maintained by causing the compressor 38 to operate intermittently. The compressor is driven by a motor 85 and the starting and stopping of the motor is controlled by a thermostat T. This thermostat may be placed at any desired place in the room and when the temperature of the air is above a predetermined desired maximum, it closes the motor circuit including wire 66, thermostat T, wire 61, motor 65 and wire 68. The refrigerating apparatus will then operate to reduce the temperature of the air flowing over the evaporators 34 and 5| and when the temperature of the air is decreased to a predetermined relatively lower temperature, the thermostat T will interrupt the motor circuit. 1

It is also desirable to control the relative humidity of the air and for this purpose there is provided a humidostat H for controlling the valve 53. The valve 53 is magnetically operated and includes a solenoid core 10 which functions as a valve and is lifted from its seat when the magnet coil II is energized. The valve II is energized when the relative humidity of the air in the room is high and this valve is maintained open until the relative humidity is decreased to a desired minimum at which time humidostat H will interrupt the circuit to the coil 'II and will maintain same interrupted until the relative humidity increases to a certain higher value. circuit for the coil includes wire 66, thermostat T, wire 12, humidostat H, wire 13, coil H and wires 14 and 88. When the relative humidity of the air is higher than that desired, the flow of gaseous refrigerant fromthe evaporator 50 is unrestricted and therefore the temperature of the evaporator will be decreased to below the dew point of the air causing a precipitation of moisture and a consequent dehumidification 'of the same. After the relative humidity of the air.

has been decreased to a desired lower value, the valve 53 will close and the flow of gaseous refrigerant from evaporator 50 will be restricted to that which can flow through the restricting pipe 64. The evaporator 50 will thenincrease in temperature and only or principally sensible heat will be removed from the air.

The air after passing over evaporators 34 and 50 will thoroughly mix in the bottom of the cabinet 23 and in the compartment 251 Therefore the relatively cold air from evaporator 50 will be tempered by the relatively warm air from evaporator 34.

It is desirable to cause a continuouscirculation of air in the room 20 and therefore the fan motor 32 operates continuously, it being connected as follows, wires 66 and 18, motor 32 and wires 11, 14, and 88.

The

Although I have shown the heat absorber 34 as comprising an evaporator of a mechanical refrigerator, it is to be understood that any suitable type of heat absorber may be employed. When the heat absorber 34 is in the form of an evaporator and as herein shown operatively connected with the compressor 38, it is desirable that the low pressure side of the refrigerating system be maintained independent of one another so that when the compressor cylinder 58 is operating to produce a relatively low pressure, gaseous refrigerant from evaporator 34 will not flow to the low pressure side of the refrigerator system including evaporator 58 and cylinder 58. Gaseous refrigerant from pipe 51 is connected to the crank case 18 of compressor 38 as is well known in the art while the pipe 35 does not enter the crank case and therefore the low pressure sides of both systems are maintained entirely independent of one another. The oil which is usually contained in the crank case 18 for lubricating the working parts of the compressor 38 is usually miscible with the refrigerant employed and consequently some of the oil flows through the condenser 38, receiver 40 and into the evaporators 34 and 50. The oil from evaporator 50 can return directly to the crank case 18 because the pipe 51 is connected with the crank case. In order to return oil from evaporator 34 to the crank case .without subjecting the crank to the relatively higher pressure in pipe 35, the pipe 35 extends through a float chamber which incloses a float 8 l,which float actuatesaneedle valve 82. The bottom of the chamber 80 is connected with a pipe 83, the inlet of which is controlled by the valve 82. After a predetermined quantity of oil is returned to the chamber 80, the float 8| will rise to lift the needle valve 82 and permit the oil to flow into pipe 83 and be returned to the compressor crank case 18 by said pipe.

Under certain conditions it will be desirable to cause some precipitation of moisiture at the absorbers 34 and 50 when these absorbers are operating at substantially the same temperature, and it is to be. understood that when the absorber 34 is referred to as functioning to remove only or principally sensible heat, such term is 'used merely to define the main functional purpose of said absorber 34 as distinguished from the main functional purpose of absorber 50 when absorber 58 is operating at a relatively lower temperature than absorber 34.

While the form of embodiment of the present invention as herein described constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

I claim:

1. An air conditioning system comprising in combination, a heat absorber about which air to be conditioned is circulated; a second heat absorber operating constantly independently of the first heat absorber and about which air to be conditioned is circulated, two independent refrigerant withdrawing means formaintaining said constant independent operation between said two heat absorbers, and means responsive to the relative humidity of air for varying the cooling effect of one of said heat absorbers relative to the other.

2. An air conditioning system comprising in combination, a heat absorber about which air to be conditioned is circulated; a second heat absorber operating constantly independently of the first heat absorber and about which air temperature of the air for controlling the amount of heat absorbed .by the specific heat absorbers; and means responsive to the relative humidity of such air for varying the cooling effect of one of said heat absorbers relative to the other.

3. An air conditioning system comprising in combination, a heat absorber about which air to be conditioned is circulated; a second heat absorber operating constantly independently of the first heat absorber and about which air to be conditioned is circulated, two independent refrigerant-withdrawing means for maintaining said constant independent operation between said two heat absorbers, means responsive to the temperature of the air for controlling the amount of refrigerating mediums flowing through said heat absorbers; means responsive to the relative humidity of. the air for varying the amount of refrigerant flowing through one of said heat absorbers relative to the other.

4. An air conditioning system. comprising in combination, a plurality of evaporators about which air to be conditioned is circulated, sepa rate and independent sources of low pressure withdrawing means, means connecting said sources to the respective evaporators for constant independent operation of the evaporators, and means responsive to the temperature and humidity conditions of the air for controlling the amount of heat absorbed by the evaporators.

5. An air conditioning system comprising in combination, a plurality of evaporators about which air to be conditioned is circulated, separate and independent sources of low pressure withdrawing means, means connecting said sources to the respective evaporators for constant independent operation of the evaporators, and means responsive to the relative humidity of the air for controlling the operation of one of said evaporators.

6. An air conditioning system comprising in combination, a plurality of evaporators about which air to be conditioned is circulated, separate and independent .sources of loiii pressure withdrawing means, means connecting said sources to the respective evaporators for constant independent operation of the evaporators. a.

, the other.

valve for controlling the flow of refrigerating medium through one of said evaporators, and means responsive to the relative humidity of the air for controlling said valve.

7. An air conditioning system comprising in combination, a pair of heat absorbers operating constantly independently of one another, and about which air to be conditioned is circulated, two independent refrigerant withdrawing means for maintaining said constant independent operation between said two heat absorbers, and means responsive to a change in the relative humidity of the air for changing the temperature of one of said absorbers relative to one another.

8. An air conditioning system comprising in combination, a pair of heat absorbers operating constantly independently of one another, and about which air to be conditioned is circulated, two independent refrigerant withdrawing means for maintaining said constant independent operation between said two heat absorbers, and means responsive to the temperature of the air for controlling the heat exchange between the air and the heat absorbers, and means responsive to a change in the relative humidity of the air for changing the temperature of one of said absorbers. relative to one another.

9. An air conditioning system comprising in combination, a pair of heat absorbers for cooling air, heat dissipating means having two inlets, said heat absorbers being connected with the heat dissipator, one to each inlet, so that the temperatures of the heat absorbers are maintained constantly independent. of one another, and means responsive to the relative humidity of the air for varying the cooling effect of one of the heat'absorbers relative to the other.

10. An air conditioning system comprising in combination, a pair of heat absorbers for cooling air, heat. dissipating means having two inlets, said heat absorbers being connected with the heat dissipator, one to each inlet, so that the temperatures of the heat absorbers are maintained constantly independent of one another, means responsive to the temperature of the air for controlling the amount of heat absorbed by the absorbers, and means responsive to the relative humidity of the air for varying the cooling efiects of one of the heat absorbers relative to LAWRENCE A. PHILIPP.