US2892324A - Refrigeration system with heat reclaiming means - Google Patents

Description

June 30, 1959 L. K. QUICK 2,892,324

REFRIGERATION SYSTEM WITH HEAT RECLAIMING MEANS Filed May 51, 1955 AIR FILTER 9 COIVDEI SER COMPQFSSOR EEFB/G EQ/IrESPA c E 6 1575? K. QUICK a, INVENTOR.

United States Patent REFRIGERATION SYSTEM WITH HEAT RECLAIMIN G MEANS Lester K. Quick, Eugene, Oreg.

Application May 31, 1955, Serial No. 512,112

Claims. (Cl. 62-455) This invention relates to a refrigeration system and more particularly to a refrigeration system wherein provision is made for maintaining the system operating within an optimum range so that greater efficiency of operation may be had.

In the operation of the ordinary refrigeration system it is well recognized that using the ordinary refrigerating gases the operating efliciency of the system is dependent upon operation within a relatively narrow range pressure of the refrigerant gas in the compressor. Pressure of a gas is directly related to temperature.

It is therefore an object of this invention to provide a refrigeration system in which means are provided for maintaining the operation of the system within an optimumrange of compressor head pressures of the refrigerant gas employed.

' operating within a definite temperature range so that the head pressure at the compressor is maintained within the said optimum range.

Another object of this invention is to utilize heat generated in the refrigeration system for maintaining air temperature such that the said air when passing over the condensing unit of the refrigerating system is at a temperature which will maintain the refrigerant pressure in the system and at the compressor within the optimum range.

' Another object of this invention is to provide a unique and novel air cooled condensing unit for use in a refrigeration system wherein the pressure of the refrigerant gas is maintained within the optirmnn range.

Other objects and advantages of this invention it is believed will be apparent from the following detailed description of a preferred embodiment thereof as illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a diagrammatic view of a refrigeration system embodying my invention illustrated as incorporated within a building.

Figure 2 is a diagrammatic view of a modified form of condensing unit applicable for use in the system embodying my invention.

The refrigeration system embodying my invention includes the ordinary gas refrigerating cycle wherein the the commonly employed refrigerating gases is compressed in a compressor 1 to a pressure such that when the gas is passed through acondenser 2, the gas will be condensed "to a liquid. The condensed refrigerant passes from the condenser to a receiver 3 and from the receiver passes through theexpansion valve 4 to the evaporator 5 wherein may be used for any of the common purposes for which gaseous refrigerant such as ammonia, Freon, or other of .2-B and 2-C, which may be connected, if desired, to

other evaporators located in an ice cream case and freezer case, for example. The condenser in this case is an aircooled condenser which may be of either the form illustrated in Figures 1 or 2 hereof.

As illustrated in Figure 1, the condenser is positioned within acasing 6 which in this case is illustrated as in an elevated position within an enclosure, room or store and the casing is provided with a room inlet 7 taking air from within the store or building and an outside air inlet 8 through which air may pass from the outside of the building. Within thecasing 6 there is provided a fan 9 operated by amotor 10 which draws the air over thecondenser 2 and may discharge the said air either into the building or store through an outlet 11 or into the outside atmosphere through anoutlet 12.

The air circulation system as provided is such that when the air is drawn from the building through the inlet 7 it is preferably discharged back into the building through the outlet 11 and in passing over thecondenser 2 absorbs the heat from the gas being condensed and operates as an aid to the heat of the building.

Positioned within thecasing 6 is anauxiliary heating element 13 which may be either a hot water, steam or other heating unit which will supplement the heating of the air to that degree required to maintain the temperature within the store or building at the desired temperature of say 65 F. during winter or the colder days of the year. In the hotter days when heat is not required within the store or building, thedampers 14 and 15 controlling the air passage through the inlet 7 and outlet 11 are closed and thedampers 16 and 17 controlling the air passage for the outside air through the inlet 8 and out theoutlet 12 are opened so that outside air is drawn over thecondensing unit 2 to condense the refrigerating gases therein and this heated air which is not then desired within the store or building is discharged into the atmosphere.

Under ordinary conditions of operation, the range of temperature at which thecondensing unit 2 would be operating in the system as thus outlined is between 65 F. and the temperature of the outside or ambient temperature which may under ordinary circumstances range between a maximum of to F., or the entire temperature range would be a range of 35 F.

Thus with the system as indicated in Figure 1, the head pressure of the refrigerant gas at the compressor would not drop too far below the optimum pressure of approximately lbs. for a Freon gas and even in the worst conditions of summer, would not build up to a temperature such that the operating efliciency would be seriously impaired.

In order that the system may operate without care, I have provided a control motor 18 which is connected through a lever system 19 with thedampers 14, 15, 16 and 17 and with atemperature switch control 20 such that when the temperature within the building is such that no heating of the return air is required, that the motor 18 will be energized to operate to close thedampers 14 and 15 and open thedampers 16 and 17 thus utiliz ing the ambient outside air over the condenser for condensing the refrigerant gases.

In Figure 2 I have illustrated a modified form of condensing element which has the advantage over that illustrated in Figure 1 of maintaining the condenser operating at an air temperature which is within much narrower limits than in the example set forth in Figure 1.

In this modified form of my invention I employ, as in the illustration of Figure 1, a finned type air operating condensing coil 2a which in all respects may be precisely the same in construction and operation as the condenser. 2. In the air stream maintained within the casing 6a and in advance of the condenser 2a I removably position afibre pad 21a which is a wettable pad similar in all respects to those used in evaporative cooling units for evaporating water in an air stream to lower the temperature of the air passing through the pad.

In this modification of my invention when outside elevated temperature air is being used to cool the refrigerant gases within the condenser 2a, water is passed over thepad 21a so that the said air is cooled by the evaporation of the water in passing through the pad. In this case the sensing element of a thermostat 22a is located in the air inlet 8a having the damper 16a therein. The thermostat may be set to operate, for example, at 80 F. air to operate thesolenoid valve 23a which controls the water drain from thepan 24a and to operate asecond solenoid valve 25a in awater supply line 26a.

Positioned within the water supply line is a pressure operated switch 27a which is positioned within the circuit controlling the current supply to theelectric motor 28a operating the water pump 29a. Afloat valve 30a may be provided within thewater pan 24a to control the water level within the said pan.

The operation of this system is that when the outside air rises to a temperature of 80 F., or above, the normally openeddrain valve 23a which is positioned within thedrain 31a of thepan 24a is closed and thesolenoid valve 25a at thewater supply line 26a is opened to permit water under pressure to flow through theline 26a and to pressurize the water pressure switch 27a setting in operation themotor 28a driving the water pump 29a. Thus water is supplied through thespray elements 32a onto thepad 21a. Air from the outside is then drawn over thepad 21a by means of thefan 9a. The air in passing over the pad is cooled to approximately to F., depending upon the wet bulb temperature of the outside air. This maintains the air passing over the condenser 2a within the very narrow limits of the desired temperature within the store which may be from 65 F. in winter to, say a maximum of or F. in the summer, and thus maintains the head pressure of the refrigerant gas within the very narrow optimum limits desired and as desired for the particular refrigeration system utilized and the refrigerant gas being employed which, for a Freon gas, is within the range of lbs. per square inch at the compressor.

In the systems employing my invention, whether they be that of Figures 1 or 2, theauxiliary heater 13 may be set into operation by means of any suitable thermostatic control well understood in this art when the heat supplied by passing the air over thecondenser 2 is insufficient to raise the building temperature to the desired point.

In the system illustrated in Figure 2, the solenoid operatedvalve 25a is of the three-way or self-draining type, that is, it is provided with adrain outlet 33a which is opened to drain the supply line leading from thevalve 25a to thepan 24a when the solenoid valve is closed. When the temperature of the outside air falls below that temperature between which the thermostat 22a is set, thevmve 23a is also opened draining thepan 24a. Thus when air is circulated over the condenser Zn from Within the building, water is not supplied to thepad 21a and no evaporative cooling of this air is attained. By utilizing the automatic draining principles as herein set forth,

I have provided for the automatic day and night or winter control of the system illustrated in Figure 2 because the system is made self-draining. As no water is employed in this system during winter, or cold weather, no problem of winter freezing of the water in the system is present. As the system operates through the use of the air within the building during cold weather, the air-cooled condenser is not subject to the low ambient temperature of outside air during cold weather operation so that the compressor will operate at the desired head pressure and will not have to operate at the reduced pressure caused by extreme cold air condensation of the refrigerant passing through the condenser.

In addition to the foregoing of maintaining the refrigeration system operating within the optimum range, the heat of the refrigerant gases is used for the purpose of heating the air within the store so that the said air may at the same time maintain the refrigerating system operating under optimum conditions. Thus the air as heated performs the dual function.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth, but my invention is of the full scope of the appended claims.

I claim:

1. In a refrigeration system of the type including, a compressor, operable for compressing a refrigerant which is a gas at normal atmospheric pressure, a condenser in which the gas is condensed to a liquid, means for conducting the refrigerant from the condenser to an evaporator in which the refrigerant is evaporated and heated, means for returning the refrigerant to the compressor, the combination including a room, a casing in which the condenser is positioned, a refrigerated space containing the evaporator positioned within said room, means in the casing for drawing air over the condenser whereby said air is heated, the casing being provided with a first air inlet through which air from the room may pass, a first outlet from the casing for discharging the said heated air into the said room, a second inlet into the casing for admitting air outside the room into the casing, and a second outlet from the casing for discharging the outside air after passing over the condenser to the outside of the room, and means for selectively controlling the passage of air through said first and second inlets and outlets.

2. In a refrigeration system, including a compressor for compressing a refrigerant gas, a condenser for condensing the compressed gas, an evaporator for evaporating the refrigerant condensed in the condenser to absorb heat from a refrigerated space, a room containing said refrigerated space, means for passing air from. the room over the condenser to extract heat therefrom, thereby to maintain a predetermined operating temperature range at said compressor, and simultaneously heat said air for discharge into said room at an elevated temperature thereby to heat said room, means associated with the condenser for admitting outside air to pass over the condenser to extract additional heat therefrom, in the event the room temperature is too high to extract sufficient heat from said condenser to maintain the temperature at said compressor in said predetermined range, and means for discharging said outside air into the outside atmosphere when the temperature in said room exceeds a predetermined value.

3. In a refrigeration system, including a compressor for compressing a refrigerant gas, a condenser for condensing the compressed gas, an evaporator for evaporating the refrigerant condensed in the compressor to absorb heat from a refrigerated space, a room containing said refrigerated space, means for passing air from the room through the condenser and back to the room thereby to heat the air and to maintain the temperature of the air within the room at an elevated temperature,

the air heated by said condenser and returned to said room being maintained within said room at a temperature range tending to effect extraction of heat from said condenser in an amount which will maintain a desired head pressure of the refrigerant gas at the compressor, and means associated with the condenser for admitting outside air to pass over the condenser and to be discharged into the outside atmosphere when the temperature within the room is higher than said temperature range.

4. In a refrigeration apparatus applicable for maintaining the operation of the refrigeration system under optimum conditions, said combination including a compressor for compressing the normally gaseous refrigerant, an air-cooled condenser for condensing the compressed refrigerant to a liquid and an evaporator for the refrigerant, which combination includes a room in which the air temperature is to be maintained below a preselected maximum, a refrigerated space within but insulated from said room, the evaporator being within the refrigerated space, means for passing air from said room over the condenser and discharging said air into the room to heat the air within the room, and means operable, when the temperature of the air within the room reaches said maximum, for drawing ambient air without the room to pass over the condenser and to be discharged back exterior to the room and for arresting the flow of air from within the room over the condenser and back to within the room.

5. In a refrigeration apparatus applicable for maintaining the operation of the refrigeration system under optimum conditions, said combination including a compressor for compressing the normally gaseous refrigerant, an air-cooled condenser for condensing the compressed refrigerant to a liquid and an evaporator for the refrigerant, which combination includes a room, the temperature of which it is desired to be maintained below a predetermined maximum, a refrigerated space within but insulated from said room, the evaporator being Within the refrigerated space, means for passing air from the room over the condenser and discharging said air into the room to heat the air within the room, means operable, when the temperature of the air within the room reaches a maximum, for drawing ambient air without the room to pass over the condenser and to be discharged back exterior to the room and for arresting the flow of air from within the room over the condenser and back to within the room, and cooling means in the path of the ambient air for cooling the air to said desired maximum before said air passes over the condenser.

References Cited in the file of this patent UNITED STATES PATENTS 1,942,295 Kerr Jan. 2, 1934 2,130,089 Hull Sept. 13, 1938 2,323,511 Baker July 6, 1943 2,513,010 Deverall June 27, 1950 2,655,795 Dyer Oct. 20, 1953 7,702,456 Ringquist Feb. 22, 1955

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