US2131355A - Refrigerating system for cooling or heating - Google Patents

Description

Sept. 27, 1938. 7 CR. NEEsoN. I

' REFRIGERATING SYSTEM FOR COOLING on HEATING Filed Jan. 25, 1953 2 SheetS-Sheet 1' INVENTOR C. R. Neesan Sept. 27, 1938. c, R NEESQN 2,131,355

REF I'GERATING SYSTEM FOR COOLING on HEATING Filed Jan. 25, 1933 2 Sheets-Sheet? mme-awezmk d/V/f INVENTOR Patented Sept. 27, 1938 Charles R. Neeson, New Rochelle, N. Y., 'assignor to Baldwin-Southwark Corporation, a corporation of Delaware Application January 25, 1933, Serial No. 653,466

16 Claim, (01. 62-115) This invention relates generally to air conditioning apparatus employing a refrigerating system and more particularly to an improved method and apparatus for interchanging the condenser and evaporator functions whereby a refrigerating system may be effectively employed eitherto heat or cool the air of a room or office.

It is well known under ordinary temperatures that a condenser in a refrigerating system gives off more units of energy, in theform of heat, than is put into the system for operating the mechanical apparatus thereof, this being on account of the refrigerating system serving merely as a mechanism for transferring heat rather than generating the heat with the result that a given amount of energy may effect transfer of a larger amount of energy in the form of heat, although someheat is of necessity generated by the work necessary to effect said transfer.

In refrigerating systems a room or space is cooled by absorbing room heat through the evaporator and then giving up the heat through the condenser, the condenser heat usually being dissipated in the outside atmosphere in the case of an air cooled condenser, or in a flow of water in the case of water cooled condensers. It has heretofore-been proposed to reverse this cycle and instead of dissipating the condenser heat, utilize it for heating purposes in homes, ofiices or for general purposes. In such cases the evaporator is usually placed in communication with the outside atmosphere so to abstract heat therefrom, the heat then being transferred to a condenser unit which has communication with the room or building. By simply reversing the connections between the evaporator, condenser and refrigerating mechanism, it is possible to interchange the functions of the condenser and evaporator thus causing these cooperating heat exchange elements either to abstract heat from the air within the' room and transfer it to the outside atmosphere thereby cooling the room, or

to abstract heat from the outside atmosphere and the unit the same as though it had been expressly designed solely for its separate functions.

It is one object of my invention to provide a relatively simple and yet effective arrangement .for interchanging or reversing the functions of the. condenser and evaporator. heat exchange elements whereby the refrigerating system may be used either for heating or cooling aroom, oflice or other space. In one specific aspect of the invention I provide an improved system employing a plurality of pressure reducing means sometimes specifically referred to as expansion valves or high or low pressure float regulators, the broad function of these various devices being to insure a lower pressure in the evaporator than in the condenser. Another object is to have the the flooded type and to have these means so arranged that refrigerant gas may flow freely in one direction through one of the same but is automatically controlled in flowing through the other thereof, or vice versa in case the direction of flow is in the opposite direction. Another object is to provide an arrangement such as just described and to have the plurality of pressure reducing means adapted for intercommunication with each other.

A more specific object is to have the pressure reducing means of a semi-floating type whereby refrigerant liquid from the heat exchange element serving as a condenser may pass freely through both the inoperative and operative pres sure reducing means and yet if any refrigerant gas .or vapor passes over from the condenser to the evaporator then the operative pressure reducing means will perform its additional function of effecting a temporary stoppage of refrigerant flow from the condenser to the evaporator and s after a predetermined time interval this stoppage is discontinued and refrigerant allowed to flow, whereas upon reversing the functions of the heat exchange elmentsthe respective pressure 'reducing means will automatically reverse their operations so that liquid refrigerant may now freely flow from the first of said heat exchange elements to the second thereof but the passage of refrigerant vapor into the second element will be temporarily stopped by the formerly inoperative reducing means.

A further object of my invention is to provide improved means whereby the piping connections between the high and low pressure sides of'a refrigerating mechanism may be interchangeably connected to the heat exchange elements while at the same time automatically rendering operative or inoperative the reducing means for the respective heat exchange elements in accordance with the direction of refrigerant flow therethrough.

Other objects and advantages will be more apparent to those skilled in the art from the following description of the accompanying drawings in which:

Fig. 1 is a diagrammatic perspective of a room cooler-heater unit embodying my improved reversing system;

Fig. 2 is a diagrammatic outline of my improved system; and

Fig. 3 is an enlarged transverse section through a three-way reversing valve adapted to be used in my system.

While my improved invention may be employed with any refrigerating system having a high and low pressure side, yet it is specifically shown for purposesof illustration in. a. compression system but in any event'it is particularly adapted for a system having an air cooled condenser and evaporator because with such a system it is possible to draw upon the heat in the entire outside atmosphere for transfer to the room to be heated, while on the other hand if the unit is used for cooling, the heat of the room may be easily transferred to the outside atmosphere. It is also desirable to utilize my improved arrangement in a self-contained unit adapted to be placed directly in'the room to be cooled or heated. thereby insuringmaximum emciency in operation and immediate application of the desired result of heating or cooling.

I have preferably shown my improved system in a self-contained room cooler-heater unit diagrammatically indicated at I and of the same structural arrangement as that shown in the copending applicationof H. L. Galson, Serial No. 648,772, flied December 24, 1932, now Patent No. 2,130,327. The cabinet encloses a vertical shaft motor-compressor unit generally indicated at 2 connected to heat exchange elements 3 and l which are supported above and communicate respectively with a. room air fan 5 and outside air fan 8 commonly driven by an electric motor I.

The structural details of this unit do not per' se constitute a part of my invention except as it is applicable to a cooler-heater and in this respect it will be noted from Fig. 3 of said Galson ap lication that the outside air fan, corresponding to 5 herein, circulates a considerably greater volume of air than the room air fan, corresponding to .-6 herein, this being due to the outside air fan having specifically twice the axial length of the room air fan'but otherwise identical in d1- ameter'and speed. For purposes of clarity, it will be understood that when the unit serves as va room cooler the heat exchange element 4 functions as an air cooled condenser, the air for which is supplied as indicated by dotted line arrows 8 from atmosphere outside of the room and through a duct 8. This incoming air thence passes preferably down over the motor-compresand out through preferably grilled opening llto the room, the air being cooled and dehumidified as it passes over theevaporator.

If it is desired to heat rather ,than cool the room, the functions of the condenser and evaporator' are reversed or interchanged so that heat exchange element 4 now serves as an evaporator and element 3 as a condenser whereupon it is seen that the outside air in passing over heat exchange element 4 will absorb heat from the outside air and be transferred to the heat exchange element 3 now serving as the condenser. The room air in passing over the element 3 will become heated andthus warm the room.

The unit-is usually operated as a heater when the outside temperature is below the point'of normal comfort. This temperature does not necessarily mean that it is cold but that it may be only chilly and/ordamp; In this case it is readily seen that the heat exchange element serving as an evaporator will be subjected to lower temperatures than would normally be the case when the evaporator is being used to cool the room air asin summer time. Hence the atmospheric con ditions are conducive to forming ice or frost on the evaporator when the outside air flows thereover, and it is of course desirable to eliminate frosting or icing if possible or at least to minimize this action as far as possible in order high velocity of air flow over its cooperating heat exchange element. Hence this outside air will not be dehumidiiied to the same extent as if the air had a lower velocity with the result that less opportunity is aflorded for icing or frosting of the outside heat exchange element serving as an evaporator. However, when the functions of the heat 'exchange'elements are interchanged so as to cause the unit to serve as a room cooler, then this larger volume of outside air flowing over what will now be the condenser has the desirable effect of cooling the condenser more emciently than if a smaller volume of air were circulated thereover. 0n the other hand, the lower volume and velocity of room air flowing over what is now the evaporator will effectively dehumidify the room air which is very desirable. Hence it is seen that the improved combination between the air circulating means and the interchangeable element may be serving these functions.

a,1a1,aos

diagrammatically shown in Fig. 2 a refrigerating system employing for each heat exchange element 3 and 4 preferably high pressure float valves generally'indicated at l5 and I6 for controlling the flow of refrigerant from the condenser to the evaporator irrespective of which heat exchange These float valves or equivalent means for controlling flow of refrigerant from the condenser to the evaporator or for reducing the refrigerant pressure are shown as connected to heat exchange elements having headers l1 and i8 which are connected by suitable pipes, although it is of course apparent that any .suitable refrigerant coils could be employed, but in any case it is desirable to have the two heat exchange elements of substantially the same thermal capacity.-

As the float valves are identical in construction, it will suflice to describe only one although when necessary to refer to the component parts of the two valves, the parts of valve IE will be given the same reference number as for valve l5, except primed. It comprises a cylindrical metal shell l9 having end covers 20 and 2| preferably welded thereto. The upper cover in turn is preferably secured to the header or other portion of the heat exchange element at the lowermost portion thereof, although under certain circumstances the trap may be connected to the heat exchange element at various elevations thereof. The fluid connection is formed by an opening 22 in which a valve seat bushing 23 is disposed. This bushing has a relatively small orifice as shown, adapted to be controlled by a small semi-spherical valve 25 suitably mounted on an arm 24, one end of which is pivoted on a bracket 26 and the other end of which is pivoted to a bracket 21 which is secured to a float 28. The float has an open lower end, the,edges of which are adapted to rest upon three or four radial ribs 29, thereby to hold the lower edgeiof the float in spaced rela-.--

' opening 3| and these openings for both traps l5 and I6 are commonly connected by a pipe 32. g

The refrigerating mechanism in the form of a positive displacement or piston type pump 2 has discharge pipes 35 and 36, from the two compressor cylinders, commonly connected by pipe 31 to a two-way valve generally indicated at 38. This valve is preferably of the tapered plug type and has an inner port 39 which when in the full line heating position as shown is adapted to connect the discharge pipe 31 with a pipe 40 leading pref erably to the top of the heat exchange element 3. The other heat exchange element 4 has a pipe 42 leading preferably from near the top thereof down through the pipe 43 to an inner port 44 of a twoway valve 45 preferably of the tapered plug type. This port when in the heating position shown in Fig. 2 communicates with a suction pipe 46 connected to the suction or low pressure side of compressor 2.

The refrigerant circuit used during operation of the unit as a cooler includes a pipe 50 communicating with pipe 42 and valve 38.. A pipe 5| communicates with pipe 40 and'valve 45. The two valves 38 and 45 are provided with any suitable interconnecting mechanism such as valve arms 52 and 53 pivotally connected to a common actuating rod 54 preferably manually operated, although if desired a single valve generally indicated at 55 in Fig.3 may be employed to permit .Pipe 42 to be directly connected to the valve for communication with an internal valve port 53 while pipe 40 is adapted to have communication with aninternal valve port 51 in the position of the valve as shown. Inasmuch as one or the other of ports 58 and 51 conduct either hot refrigerant gases from the compressor or cooled condensed liquid refrigerant from the condenser to the evaporator, I have provided suitable means for insulating these two ports, such means being specifically shown at 53 in the form of rubber .ex-

tending for a substantial axial length of the rotatable plug 59. Any other suitable insulating material may of course be inserted in the insulating space between these ports or under certain.

circumstances the space may be leftunfilled. The single valve 55 may thus be employed in place of the two valves 38 and 45 although the double valve has the advantage of insuring maximum insulation between the hot and coldphases of the refrigerating cycle.

Operation of unit as heater.-With valves 33 and 45 in the full line position as shown the unit is adapted to function as a heater in that compressed refrigerant gases from'compressor 2 are discharged from each of the compressor cylinders V 60 and GI into pipes 35 and 38. ,The path of the refrigerant during the heating operation is indicated by the fullline arrows 3 whereas the dotted line arrows C are the path of the refrigerant during the-cooling operation which will be described later. During heating the compressed refrigerant gas flows through pipe 31, port .33. thence'through pipe 40 to condenser 3 in which the refrigerant vapor is condensed by circulation of.-room air over the surfaces of the :heat exchange element 3. As shown in Fig. 1, this room air is circulated by fan 5 driven by an electric motor 1,

the air entering through a suitable inlet l2 at one end of a cabinet I and thence generally following the direction of the dotted line H to discharge into the room through a suitable outlet H in the top of the cabinet.

As the refrigerant condenses it accumulates in the lower portion of the heat exchange element 3, serving as a condenser and is adapted to flow at all times downwardly through an orifice 22' nism IS, the condensed liquid refrigerant thence lower open edge of float 28' as indicated byarrow flowing downwardly and upwardly around the,

- 62 and thence into pipe 32 and up into the lower #7 open end of float 28 and thence downwardly and upwardly around the lower edge thereof as indicated by arrow 63, the liquid refrigerant continuing upwardly through the orifice -in bushing 23 into the heat exchange element 4 now serving as an evaporator. The liquid refrigerant is'maintained at a lower pressure in the evaporator than in the condenser and hence absorbs heat from As the liquid refrigerant is vaporizedjiy ab-fi sorbing heat from this outside atmosphere, the vapor passes off through pipe 42, passage 43, in-

ternal valye port 44 and pipe 46 to the suction side of the compressor to repeat the cycle above 4 a,1s1,sss

the float control mechanism I8 is inoperative but;

I float mechanism I8 is operative to prevent refrigerant vapor passing over through pipe 82 which may be caused by a temporary inability of the condenser to condense the refrigerant as rapidly as the demand. When such vapor or gas initially l flows into the lower open end of float 28, it will accumulate in the upper part thereof and immediately cause float 28 to rise and accordingly move arm 24 about its stationary pivot 28, thus causing ball valve 25 to seat in the orifice of bushing 28 and prevent any further flow of refrigerant whether gas or liquid. The gas which is thus trapped in float 28 gradually leaks out through leak port 30, this port being shown somewhat enlarged in the drawings for purposesof clarity, U although its size may be varied in accordance with the time lag that may be desired in permitting suiiicient accumulation of further condensed refrigerant. However, as the gas gradually leaks through port 30, float 28 will of its own weight as move downwardly until finally ball valve unseats the orifice in bushing 23 to allow further how of refrigerant into the evaporator 4. Before suflicient gas has passed through leak port 30 to permit opening of said orifice, it is assumed that so sufficient refrigerant will have been condensed so that only liquid refrigerant will pass into the evaporator. If suflicient refrigerant has not been condensed, then a further amount of gas will 'pass over into float 28 and again close the valve 28.

From the foregoing description it is seen that valve mechanism It remains inoperative while float valve mechanism [5 is operative. versing the refrigerating cycle in order to have the. unit serve as a room cooler, valve mechanism I5 is automatically rendered inoperative and valve mechanism l6 rendered operative.

Operation of unit as a cooler.-To c e the unit to serve as a. room cooler, it is only necessary I 4,5 to interchange the condenser and evaporator functions of heat exchange elements 3 and 4 and to accomplish this, operating link 54 is moved so as to simultaneously rotate valve ports 39 and 44 through 90 to the dotted line positions 39' and 5 44' shown in valves 38 and 45. The path of flow of the refrigerant is now indicated by the dotted line arrows C. Compressed refrigerant gas is discharged from cylinders and SI through pipes 35 and 36 to pipe 31, thence through the 55 dotted line position 39' of the valve port to pipes 50 and 42 and thence into heat exchange element 4 now serving as a condenser from which refrigerant may flow freely downwardly through orifice 22 and thence downwardly-and upwardly 80 around thellower open end of float 28 to flow through pipe 32 to valve mechanism,l6. This valve mechanism will now function the same as above described for valve l5 during the heating operation and hence a detailed description of the es operation of valve I6 is not necessary. It will suflice to state that the liquid refrigerant will flow upwardly through orifice 22 to heat exchange element 8 now serving as an evaporator over which room air is circulated to be cooled. The refrigerant gas vaporized by absorbing heat from the room air will now flow downwardiy- -through pipe 40 to pipe SI and through valve 45 in the dotted line position 44' of the valve port-to pipe 48 and'the suction side of the compressor. a His seen from the foregoing description that Inre-- valve mechanisms II and II are rendered opera-- tive or inoperative automatically in accordance with the direction of flow of refrigerant throughthe heat exchange elements or automatically in accordance with whether one of the heat ex- I change elements serves as either a condenser or evaporatory'ail of this being accomplished in a relatively simple and yet highly effective manner without interfering withthe emciency-of the rebeemployed ina sealed system. I

While I have shown one specific form of high pressure float controlled valve'mechanism such as I8 or l8 and have shown a plug type of valve for effecting reversal of the refrigerating cycle, and while I have also shown'a piston and cylinder 24 type compressor, yet it will be understood that the broad equivalent of these various elements may be employed and the same rearranged without departing from the spirit of the invention as set forth in the appended claims. U

I claim:

1. A refrigerating system comprising, in combination, a refrigerating mechanism, a plurality of heat exchange elements, and a plurality of refrigerant pressure reducing means connected I in series, each element having one of said reducing means associated therewith whereby either of said elements may function as a refrigerant condenser -or evaporator.

2. A refrigerating system comprising, in combination, a refrigerating mechanism, a plurality of heat exchange elements, a plurality of refrigerant pressure reducing means-connected in series, each element having one of said reducing". means associated therewith whereby either of said elements may function as a refrigerant condenser or evaporator, and means for reversing the path of refrigerant flow through said elements thereby to interchange the condenser and evaporator functions. a

3. A refrigerating system comprising, in combination, a refrigerating mechanism, a plurality of heat exchange elements each of which is adapted to serve either as a condenser or evaporator, refrigerant pressure reducing means ccn- U nected in series and associated with each of said elements, and means for interchanging the condenser and evaporator functions of said heat exchange elements thereby to render said pressure reducing means for the respective elements U operative or inoperative automatically in accordance with which element functions as the evaporator.

4. The combination set forth in claim 1 further characterized in that said pressure reducing I means are of the float controlled type.

5. A refrigerating system comprising, in combination, a refrigerating mechanism, a plurality of heat exchange elements operatively connected to said mechanism to effect a refrigerating cycle, D and float controlled pressure reducing means associated with each of said elements, each of said means having provision whereby refrigerant gas or liquid may flow at all times therethrough in one direction. and flow of refrigerant gas therell through inthe opposite direction being substantially restricted while liquid flow in said opposite direction is unrestricted.

6. A refrigerating system comprising, in combination, a refrigerating mechanism,a plurality of heat exchange elements, means for operatively connecting said elements to said refrigerating mechanism whereby one of said elements may of. said heat exchange elements, each of said reducing means having an inverted float with one end closed and the other end open and a gas leak port in the closed end.

8. A refrigerating system comprising, in combination, a refrigerating mechanism, a plurality of complementary heat exchange elements, means for connecting said elements to said mechanism to effect a refrigerating cycle with said elements respectively serving either as a condenser or evaporator, and high pressure float controlled pressure reducing means connected in series and associated with each of said elements.

9. A refrigerating system comprising, in combination, a refrigerating mechanism, a plurality of complementary heat exchange elements, and means for interchangeably connecting said elements with said mechanism whereby said elements respectively may serve as a condenser or evaporator, each of said elements having a float controlled pressure reducing valve mechanism having provision for allowing flow of condensed refrigerant from the condenser to the evaporator and to temporarily discontinue said flow automatically when refrigerant gas passes over with 10. In a refrigerating system having complementary heat exchange refrigerant elements, means for interchanging the functions of said elements so that one serves as a condenser and the other as an evaporator or vice versa, and each of said elements having pressure reducing means connected in series and respectively rendered operative or inoperative automatically in accordance with whether one of said elements is serving as a condenser or evaporator.

11. A refrigerating system comprising. in combination, a pair of complementary heat exchange elements respectively adapted to function as a condenser and evaporator, and means for interchanging the functions of said heat exchange elements including intercommunicating float controlled pressure reducing means associated with each of said elements.

12. A refrigerating system of the flooded type comprising a pair of complementary heat ex- 'change eleme'nts adapted to serve either as a condenser or evaporator, each of said elements having a float controlled pressure reducing means communicating with the lower portion of its respective element and with each other, and means for interchanging the condenser and evaporator functions of said elements. 4

13. A refrigeratingsystem comprising, in combination, a refrigerating mechanism, a plurality of heat exchange elements respectively performing evaporator and condenser functions, means for interchanging the functions of said elements, a plurality of refrigerant pressure reducing means each having a single flow passage for either direction of refrigerant flow, and means adapted, automatically in accordance with which element is functioning as the evaporator, to allow flow of refrigerant liquidthereto but to substantially prevent flow of-refrigerant gas thereto.

14. The combination set forth in claim 13 further characterized in that said refrigerant pressure reducing means are of the float operated ype.

15. A refrigerating system comprising, in combination, a refrigerating mechanism, a'plurality of heat exchange elements respectively performing evaporator and condenser functions, and

means for interchanging the functions of said elements including a plurality of separate refrigerant pressure reducing means connected in series, one for each of said elements, adapted automatically in accordance with which element is functioning as the evaporator to allow flow .of refrigerant sliquid thereto but to substantially prevent flow of refrigerant gas thereto. 16. The combination comprising complementary heat exchange refrigerating elements, means for interchanging the functions of said elements so that one serves as a condenser and the other as an evaporator or vice versa, means for circulating room air over one of said elements, and means for circulating outside air over the other of said elements at a velocity greater than the room air velocity whether or not said elements are performing condenser or evaporator func-

Images