US3613392A

US3613392A - Attachment for air-cooled cooling units

Info

Publication number: US3613392A
Application number: US885879A
Authority: US
Inventors: Charles Di Tucci
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-12-17
Filing date: 1969-12-17
Publication date: 1971-10-19
Anticipated expiration: 1988-10-19

Abstract

AN AIR-COOLED COOLING UNIT HAVING CONDENSER COILS IN THE PATH OF A STREAM OF COOLING AIR. A SPRAY TUBE FORMS PART OF AN ATTACHMENT WHICH CAN BE ATTACHED TO AN EXISTING AIR-COOLED COOLING UNIT FOR SPRAYING WATER IN THE SPACE OCCUPIED BY THE CONDENSER COILS. A VALVE IS PROVIDED FOR OPENING AND CLOSING THE TUBE. THIS VALVE MAY BE A SOLENOID VALVE OPERATIVELY CONNECTED WITH A SENSING UNIT SUCH AS A THERMOSTAT WHICH SENSES THE OUTSIDE TEMPERATURE FOR OPENING THE VALVE TO ADMIT WATER TO THE SPRAY TUBE WHEN THE AMBIENT TEMPERATURE RISES TO A GIVEN VALUE. IN ADDITION A THERMAL BULB MAY BE OPERATIVELY CONNECTED WITH THE LIQUID LINE TO OPEN THE VALVE WHEN THE LIQUID IN THE LIQUID LINE RISES TO A GIVEN TEMPERATURE. IN THIS WAY ADDITIONAL COOLING FOR THE CONDENSER COILS IS ACHIEVED ONLY UNDER OVERLOAD CONDITIONS.

Description

Oct. 19, 1911 c, D. Tucc. 3,613,392

ATTACHMENT FOR AIR-COOLED COOLING UNITS Filed Dec. 17, 1969 INVI'JNI'UH. CHARLES DI TUCCI 54 17; L, E] YS United States Patent O1 ifice 3,613,392 Patented Oct. 19, 1971 3,613,392 ATTACHMENT FOIEIAJICOOLED COOLING Charles Di Tucci, 246-12 63rd Ave., Douglaston, N.Y. 11362 Filed Dec. 17, 1969, Ser. No. 885,879 Int. Cl. F25b 39/04 US. Cl. 62184 Claims ABSTRACT OF THE DISCLOSURE An air-cooled cooling unit having condenser coils in the path of a stream of cooling air. A spray tube forms part of an attachment which can be attached to an existing air-cooled cooling unit for spraying water in the space occupied by the condenser coils. A valve is provided for opening and closing the tube. This valve may be a solenoid valve operatively connected with a sensing unit such as a thermostat which senses the outside temperature for opening the valve to admit water to the spray tube when the ambient temperature rises to a given value. In addition a thermal bulb may be operatively connected with the liquid line to open the valve when the liquid in the liquid line rises to a given temperature. In this way additional cooling for the condenser coils is achieved only under overload conditions.

BACKGROUND OF THE INVENTION The present invention relates to air-cooled cooling units of the type used for cooling the interior space of residential or commercial buildings.

There are many different types of circumstances under which it is possible for cooling units of this type to encounter overload conditions. For example when the outside temperature becomes hotter than usual, the condenser coils are not cooled properly, giving rise to overload conditions. It may be, for example, that a given condensing unit is not of a capacity which is large enough for the required job. Also, it may be that due to certain circumstances the condenser is situated in the direct rays of the sun. In addition it is possible for the structure to be situated indoors where there is no adequate circulation of air. Also under these latter conditions it is possible for the indoor area to have an undesirablly high temperature.

Condensers of such air-cooled units are designed to have an exterior surface area adequate to peak loads. However, it frequently happens that this exterior surface area of the condenser coils will become covered or clogged with a film and dirt, so that overload operations can also be encountered under these conditions.

SUMMARY OF THE INVENTION It is accordingly a primary object of the present invention to provide a structure capable of avoiding the above drawbacks.

In particular, it is an object of the invention to provide an attachment which can be attached to existing aircooled cooling units to assure proper operation even under overload conditions.

In particular, it is an object of the invention to provide a structure such as an attachment which will not operate until overload conditions are encountered.

Furthermore, it is an object of the invention to provide an attachment of the above type which will respond not only to outside or ambient conditions but also to conditions in the cooling unit itself in order to detect overload conditions.

Yet another object of the invention is to provide an attachment which is relatively simple and inexpensive and which can be readily attached to any existing air-cooled cooling unit with simple tools readily available to any person of average mechanical skill so that the attachment of the invention can be purchased at low cost and conveniently and quickly applied to an existing air-cooled cooling unit to alleviate overload operating conditions in a fully automatic manner.

According to the invention the attachment includes a spray means for spraying water into the space occupied by the condenser coil of an air-cooled cooling unit. A valve means is operatively connected with the spray means for directing water thereto when the valve means is in an open position and for preventing flow of water thereto when the valve means is in a closed position. A sensing means is provided for sensing the occurrence of overload operating conditions, and this sensing means is operatively connected with the valve means to place the latter in its open position when overload operating conditions are encountered and to maintain the valve means in its closed position when there are no overload operating conditions.

BRIEF DESCRIPTION OF DRAWINGS The invention is illustrated by way of example in the accompanying drawings which form part of this application and in which:

FIG. 1 is a fragmentary schematic perspective illustration of the condensing section of an air-cooled cooling unit having the attachment of the invention joined thereto;

FIG. 2 is a fragmentary schematic transverse section taken along line 22 of FIG. 1 in the direction of the arrows and showing part of the structure;

FIG. 3 illustrates the attachment of the invention in the condition it has when initially purchased;

FIG. 4 is a schematic wiring diagram illustrating the manner in which the electrical structure operates.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIG. 1 there is schematically illustrated therein the housing 10 for the condenser coils 12 of an air-cooled cooling unit. As is well known, the interior air which is to be cooled is directed through suitable blowers or the like over the evaporating coils. The evaporated refrigerant is then compressed while flowing through a condenser unit such as that which is shown in FIG. 1. In this way the refrigerant is converted back into a liquid to flow along a liquid line 14, part of which is illustrated in FIG. 1, back to the evaporator. The condenser coils 12 are in the form of tubes having fins 16 thereon. An unillustrated fan directs cooling air over these coils, and this cooling air is generally the outside ambient air which is directed over the coils, as indicated by the arrow 18. The cooling air may initially be filtered, and then it will pass through the space occupied by the condenser coils so as to carry heat away from the latter this heat being discharged to the outside, as is well known.

With air-cooled cooling units of this conventional, classic type, it may happen that overload conditions are encountered as a result of a variety of different circumstances. For example during an excessively hot day, such as a day where the outside temperature is over F., the cooling air 18 which is directed over the condenser coils is at such an elevated temperature that the required cooling does not take place, with the result that overload operating conditions are encountered. The result is that the normal range of head pressure cannot be maintained, and with constant operation under such overload conditions for an appreciable length of time, breakdown of the entire unit may occur.

However, it is also possible for overload conditions to be encountered even if the ambient temperature is not 3 excessively high. For example it may well be that dust, film, and the like accumulates to such an extent on the exterior surfaces of the condenser coils that a layer of insulation is in effect formed between the coils and the stream of cooling air in which they are located, so that as a result the required cooling does not take place, and overload conditions will also be encountered even though ambient temperatures are not excessively high. Under these conditions the liquid refrigerant fiowing through the liquid line 14 will have an excessively high temperature, and it is also possible due to such circumstances for the unit to break down and require repairs if it operates for a large enough time without any corrective measures.

The attachment 20 of the present invention, shown in FIG. 3 in the condition it has when purchased, includes a spray means 22 for spraying water into the space occupied by the condenser coils 12. In the illustrated example the spray means 22 takes the form of an elongated metal tube 24 of copper, for example, capable of being uncoiled from the initial coiled condition thereof indicated in FIG. 3. This tube 24 of the spray means has discharge nozzles 26 distributed therealong. At one end the tube 24 terminates in a closure end cap 28. As is apparent from FIG. 2, the outlet nozzles 26 are inclined so as to direct the spray into the space occupied by the coils of the condenser 12, and thus this spray will encounter the tubes and the fins 16' of the condenser. The size of the tube 24 and the size and distribution of the outlet nozzles 26 will be determined by the characteristics of the particular air-cooled unit. Thus, depending upon the particular tonnage of the air-cooled unit, an attachment 2.0 of a given magnitude will be purchased.

In order to connect the attachment 20 of the invention to the condenser part of an air-cooled unit, it is a simple matter to provide, for example, a notch in the Wall 29 and to fasten the uncoiled tube 24 to any available fixed components such as an elongated bar 30 (FIG. 2) extending across the housing of the unit 10 and normally senving to position an air filter with respect thereto, for example. Thus, the kit will include a fastening means which may, for example, take the form of U- shaped clips 32 and fasteners in the form of bolt and nut units 34 capable of being used for clipping the tube 24 to a component such as a bar 30.

The tube 24 terminates distant from the end cap 28 in a coupling or fitting means 36 by means of which the tube is connected to any source of water such as conventional tap water. At the region of the fitting means 36 the tube 24 carries a valve means 38 in the form of a conventional solenoid valve spring urged, for example, to its closed position and moved in opposition to the spring to an open position in response to closing of a circuit which energizes the coil of the solenoid.

Finally, the attachment 20 includes a sensing means 40 which senses the occurrence of an overload condition for actuating the solenoid valve 38 so as to place the latter in an open position. FIG. I shows an electrical conductor cable 42 leading from the attachment to a suitable source of electricity.

The sensing means 40 includes a thermostat 44 which senses the ambient temperature. This thermostat 44 may be set, for example, to close the solenoid circuit when the outside air temperatures reaches 90 F. Under these conditions the solenoid valve will be placed in its open position, directing water along the tube 24 to be sprayed out through the nozzles 26. In general the magnitude and number of the nozzles, in conjunction with the dimensions of the tube 24 are such that the sprayed liquid will become evaporated into the air surrounding the condenser coils, and in this way problems of collecting the liquid are avoided. However, a collecting tray may be placed beneath the coils with a suitable drain connected thereto if it should happen that some of the sprayed liquid does not evaporate. Some of the spray is drawn through the coils to the outside in the air stream provided by the fan, so that for this reason also the problem of collecting liquid is avoided.

The sensing means 40 also includes a thermal bulb 46 shown in FIG. 1 removably connected, as by a clip 48 to the liquid line 14 for responding to the temperature of the liquid refrigerant therein. Through a capillary tube 50 the thermal bulb 46 is also operatively connected with the solenoid valve for bringing about closing of the circuit thereof when the temperature of the liquid refrigerant is undesirably high, and in this way also the valve means 38 will be actuated to admit water to spray into the space occupied by the condenser coils. In this latter connection, as was pointed out above, it can happen that due to collection of dust, film, and the like on the condenser coils, the required degree of cooling is not achieved even though the ambient temperatures are not excessively high. For example, even at temperatures of F., it may well be that due to these conditions, the liquid in the line 14 is at an undesirably high temperature. Thus, even under these overload conditions the attachment of the invention will automatically respond to provide the spray which will result in additional cooling. However, the spray will also wash the exterior surface of the condenser coils and remove dust and film therefrom, so that in this way also a self-maintenance takes place.

As may be seen from FIG. 4, the coil 50 of the solenoid valve is connected between the lines L and L through a pair of parallel-connected normally

open switches

52 and 54. The switch 52 closes in response to operation of the thermostat 44 while the switch 54 closes in response to operation of the thermal bulb 46. A spring 56 normally locates the valve 38 in its closed position. However, when the coil 50 is energized the rod 58, which acts as an armature, is pulled up in opposition of the spring 56, thus opening the valve 38. When both of the

switches

52 and 54 are open, the spring 56 will automatically close the valve. However, when either one of these switches is closed, the valve 38 will open to admit water to the spray means 22.

It is to be emphasized that the attachment of the present invention will not operate during relatively normal conditions when no overload is encountered. Thus, if the attachment of the invention is used with a properly designed unit which is relatively new and of a large enough capacity, there will ordinarily be no operation of the attachment of the invention. It will only come into operation automatically when an excessively hot day is encountered, which might otherwise result in an overload of the unit, or it might come into play when after a given period of operation the liquid in the liquid line rises to an undesirably high temperature. Thus, this construction of the present invention is to be distinguished from those where liquid-cooling of the condenser coils is provided as a normal operation function under all operating conditions. Of course, such units are water-cooled rather than air-cooled and it is one of the outstanding characteristics of the attachment of the present invention that it can readily be attached to an air-cooled unit for providing the latter with added operating capacity only when unusual, overload operating conditions are encountered.

The invention is applicable to commercial refrigerating units operating on air-cooled condensers and not only to air conditioning. The invention is for application to any air-cooled condenser which requires a boost in capacity whether air conditioning, commercial refrigeration, or wherever a cooled condenser is used.

On large commercial and industrial units, due to their larger size, additional spray tubes will be necessary to properly cover the larger condenser surface. Where two or more tubes may be necessary, then a main feeder pipe or tube manifolded leader or header will be used, from which hard drawn or soft spray tubes with couplings or quick-connect fittings will extend, all attached for easy assembly on the job site.

What is claimed is:

1. For use with an existing air-cooled cooling unit having condenser coils in the path of cooling air, an attachment comprising spray means to be attached to the unit for spraying water into the space occupied by the condenser coils, valve means operatively connected with said spray means for preventing the flow of water thereto when said valve means is in a closed position and for admitting water to said spray means when said valve means is in an open position, sensing means operatively connected with said valve means for sensing when an overload operating condition occurs and for placing said valve means in said open position thereof when an overload condition is sensed and placing said valve means in said closed position thereof when there is no overload condition, fastener means operatively connected with said spray means for fastening the latter to a cooling unit, and coupling means operatively connected with said spray means for coupling the latter to a source of water, said coupling means, spray means, valve means, and sensing means forming an independent unitary assembly constituting an attachment completely independent of said cooling unit to be fastened thereto by said fastener means at any desired time after said cooling unit has been installed.

2. The combination of claim 1 and wherein said sensing means is a thermostat responding to a rise of the ambient temperature to a given value for automatically placing said valve means in said open position thereof when said given temperature value is reached.

3. The combination of claim 1 and wherein the unit includes a liquid line through which cooled condensed liquid flows to an evaporator of the unit, said sensing means including a thermal bulb to be operatively connected with said liquid line of said unit for automatically placing said valve means in said open position thereof when said thermal bulb senses a rise in the temperature of liquid in the liquid line up to a given value.

4. The combination of claim 3- and wherein said sensing means also includes a thermostat for sensing the ambient temperature and for automatically placing said valve means in its open position when the ambient temperature rises to a given value.

5. The combination of claim 1 and wherein said spray means includes an elongated tube having a plurality of nozzle outlets distributed therealong for directing spray to the space occupied by the condenser coils, said tube having at one end said coupling means for connecting said tube to a source of water and said tube carrying said valve means adjacent said coupling means, said sensing means being operatively connected with said valve means also at the region of said coupling means.

*6. The combination of claim 5 and wherein said tube is adapted initially to be coiled at the region provided with said nozzle outlets and situated beyond said valve means.

7. The combination of claim 6 and wherein a clip means forming at least part of said fastener means coacts with said tube for clipping the latter to the cooling unit.

8. The combination of claim 1 and wherein said valve means is a solenoid valve and said sensing means acting electrically upon said valve.

9. In an air-cooled cooling unit, a condenser having condensing coils in the path of cooling air and a liquid line extending from said coils, spray means located adjacent the space occupied by the condenser coils for spraying water into said space, valve means operatively connected with said spray means for directing water thereto when said valve means is an open position and for perventing flow of water thereto when said valve means is in a closed position, and sensing means operatively connected with said valve means for placing the latter in said open position thereof when said sensing means senses an overload operating condition and for leaving said valve means in said closed position thereof when there is no overload condition, said sensing means including a thermal bulb operatively engaging said liquid line for automatically placing said valve means in said open position when said thermal bulb senses a rise in the temperature of liquid in the liquid line up to a given value, and said sensing means also including a thermostat for sensing the ambient temperature and for automatically placing said valve means in its open position when the ambient temperature rises to a given value.

10. The combination of claim 9 and wherein said spray means includes an elongated tube having spray nozzles directed toward the space occupied by said condenser coils, and a fastener means operatively connected with said tube for fastening the latter to the cooling unit, so that the spray means can be attached to an already existing air-cooled cooling unit.

References Cited UNITED STATES PATENTS 2,185,965 1/1940 NeWill 62183 2,210,325 8/1940 Newton 62183 2,278,242 3/1942 Chapman 62183 2,325,658 8/1943 Candor 62-481 2,651,182 9/1953 Borgerd 62183 2,995,018 8/1961 Dempsey 62-305 WILLIAM J. WYE, Primary Examiner US. Cl. X..R.