US 3878886 A
An air conditioning and heating system particularly suited for but not necessarily limited to use in a drive-in theater which includes a plurality of spaced individual units each comprising a self-contained refrigeration and/or heating system together with means for distributing and recirculating air to and from vehicles adjacent the units.
Description (OCR text may contain errors)
es tent I191 Miclntire, ,1 In
SYNEIRGKSTHC HEAT EXCHANGE APPARATUS Harold 1K. Melmire, Jr., RR. 3 Ankeney Rd, Xenia, Ohio 45385 Filed: Oct. 20, 1972 Appl. No.: 299,391
US. Cl. 1455/29; 165/59; 98/2.02 Int. Cl. F251) 29/00 Field of Search 165/59, 29, 127; 98/202 References Cited UNITED STATES PATENTS 6/1965 Bell, Jr 165/29 3,360,954 1/1968 Snider et al 98/202 Priman' E.\'aminer-Char1es Sukalo Attorney, Agent, or F irmGleim and Tritle  ABSTRACT An air conditioning and heating system particularly suited for but not necessarily limited to use in a drivein theater which includes a plurality of spaced individual units each comprising a self-contained refrigeration and/or heating system together with means for distributing and recirculating air to and from vehicles adjacent the units.
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A TTOR/VE) SYNERGISTIC HEAT EXCHANGE APPARATUS BACKGROUND OF THE INVENTION The present invention relates generally to heat transfer devices and, more particularly. to an improved selfcontained system for supplying and recirculating condi tioned air.
The problems encountered in connection with attempts to provide a reasonable degree of comfort for patrons of drive-in theaters are both difficult and complex. For example, seasonal weather variations present diverging requirements such as a need for heating at one time and a need for cooling at another time. These conflicting requirements are further complicated by bugs and insects entering the interior of automobiles if the windows thereof remain open, and. at the same time, such interior maybecome uncomfortably warm to occupants if the windows are kept closed.
Installation problems and expense effectively preclude use of a central air conditioning and/or heating system at existing drive-in theaters. Such a system is equally undesirable for installation in drive-in theaters under construction because such a system is not well suited to economically handle partial cooling and/or heating loads that inevitably occur at times when the theater attendance is less than its capacity. Thus, operating expenses are relatively costly and installation such a system requires a relatively large capital inventment. 7
Individual heater units for disposition in individual vehicles are relatively inexpensive but are subject to the disadvantagethat they tend to provide excessive heat in the immediate vicinity of such heater and too little heat for the comfort of occupants of a vehicle who may be relatively near to but not within such immediate vicinity.
Similarly, individual units for merely supplying cooled air to a parked vehicle are also relatively inexpensive but certain operating conditions frequently result in such cooling units contributing to the discomfort of occupants of such vehicles. For example, cooling of high humidity air will result in an increase in relative humidity or saturation of the cooled air saturated with moisture and an increased feeling of discomfort.
SUMMARY The foregoing problems and disadvantages are overcome and other objects and advantages are achieved in accordance with the present invention which, in general. provides improved efficiencies in heating and in cooling together with humidity control by combining heating elements with cooling elements and with means for distributing and recirculating conditioned air to and from adjacent vehicles and for avoiding the mixing of recirculation air from one such vehicle with the from another.
DESCRIPTION Additional objects and advantages will become apparent from the following description in conjunction with the accompanying drawings in which:
FIG. 1 is a fragmentary perspective view of a drive-in theater embodying the present invention;
FIG. 2 is a view of an air conditioning unit embodying the invention;
FIG. 3 is a perspective view of the embodiment of FIG. 2 with certain cover parts removed to show other components;
FIG. 4 is a top exploded view of the embodiment of FIG. 2 with the top cover removed;
FIG. 5 is a side view of the embodiment of FIG. 2, partly broken away, to show disposition of several components;
FIG. 6 is a view looking in the direction of arrows 6-6 in FIG. 5; and
FIG. 7 is an elevation view of the blower housing.
Referring to the drawings wherein similar reference numerals refer to similar parts or components, air conditioning units for a drive-in theater embodying the present invention are generally shown at 10 in FIG. 1. The air conditioning unit comprises basically a case 11 which houses therein a compressor 12, an evaporator coil 13, a condenser coil l4, and a pair of blower fan motor assemblies l5, 16. As best shown in FIG. 3, the entire left hand side and the lower portion of the right hand side of case 11 are enclosed by perforate side covers such as grilles 17 which will readily permit passage of air therethrough and yet will preclude entry of sizable solid objects. Thus, fans 18, 19 draw ambient air through the lower portions of grilles I7 and blow such air through openings 20, 21 in a plate 22 at the right side of condenser coil l4. After passing through openings 20, 21, air is blown by fans I8, 19 through and across the surfaces of condenser coil 14 and is then discharged through the upper portion of grille 17.
The interconnections of the compressor. condenser, and evaporator are also best shown in FIG. 3. Compressor 12 is connected to condenser coil 14 by a pressure conduit 23 extending generally upward from the discharge of the compressor to the top of condenser coil 14. The inlet of compressor is connected to the top of evaporator coil 13 by a suction. conduit 24. The bottom of the condenser coil I4 is connected to the bottom of evaporator coil 13 by an expansion conduit 25 which includes a portion of capillary, tubing for expanding a refrigeration fluid, such as Freon, from its liquid state into its gaseous state as it passes from the capillary tubing to evaporator coil I3.
Thus. casing 11 houses a selfcontained refrigeration system in which compressor 12 withdraws a refrigeration fluid. such as Freon, from evaporator coil 13 through conduit 24 and compresses the fluid before it is conveyed via conduit 23 to condenser coil 14. During compression, the pressure of the refrigeration fluid is increased, as well as its temperature. As the refrigeration fluid passes through the condenser coil 14, it is cooled by the air blown across the coil by fans 18, 19 thus transforming the fluid from gas into a liquid. As the liquid refrigerant fluid is passed from condenser coil 14 to evaporator coil I3, its pressure is reduced so that the refrigerant expands-to its gaseous state and thereby becomes chilled. The chilled refrigerant in the evaporator coil absorbs heat from the surrounding environment so that the temperature of air inthe vicinity of evaporator coil 13 will be cooled below its initial temperature.
An air conditioning unit embodying the present invention includes self-contained means for continuously supplying and recirculating to and from adjacent vehicles air that is passed through evaporator coil I3 together with a certain amount of fresh air that may be drawn into the unit from the ambient atmosphere.
As shown in the drawings, a portion of air passing through evaporator coil 13 is received into a squirrel cage blower 26 for delivery thereby to one such adjacent vehicle. Another portion of such air is received by another squirrel cage blower 27 for delivery thereby to another such vehicle. As indicated in FIG. 3, motors 15, 16 may be of the type having a shaft extending from opposite ends thereof so that a single motor drives fan 18 as well as blower 27. Similarly. motor 16 drives fan 19 as well as blower 26. However. the interests of simplicity and compactness may be outweighed by other conflicting interests so that. if desired. it is within the scope of the present invention to provide separate motor means for driving blower 27 independently of fan 19.
Blowers 26, 27 are enclosed within an enclosure indicated generally at 28. One wall 29 of said enclosure is spaced apart from and extends generally parallel to evaporator coil 13. Wall 29 is provided with a pair of spaced openings 30, 31 defining air inlets for blowers 26, 27, respectively. The top wall 32 of enclosure 28 is similarly provided with spaced openings 33, 34 surrounded by skirts 34, 36 and defining discharge ports for blowers 26, 27, respectively.
The aforesaid spacing between wall 29 and evaporator coil 13 provides a chamber 37 which is closed by opposed side walls 38, 39, a top cover 40, and a floor 41 extending beneath evaporator coil 13 and blower enclosure 28. A heater element 42 is mounted on wall 38 and projects inwardly therefrom into chamber 37 almost to wall 39. Thus. when blowers 26, 27 are in operation, air is drawn into chamber 37 through evaporator coil 13 and is cooled thereby if the refrigeration system is in operation. Alternately, if the refrigeration system is inoperative and heater 42 is in operation. air drawn into chamber 37 is heated as it passes through the heater prior to its entry into blowers 26, 27.
Means are provided for distribution and recirculation of the cooled and/or heated air to and from adjacent vehicles. Additionally. because cigar smoke and/or odors. heavy perfume. etc. may be objectionable to certain drive-in theater patrons. it is desirable to avoid mixing of air recirculated from one vehicle with that of another.
Accordingly. in accordance with the invention. cooled and/or heated air is drawn from chamber 37 by blower'26 and is discharged thereby through discharge 7 1 opening 33 into a hose 42 having a window distribution nozzle 44 connected to the free end of the hose for distribution of the cooled and/or heated air into an adjacent vehicle. The opposite end of hose 43 surrounds and is connected to skirt 35. A similar hose 45 having a similar nozzle 46 is similarly connected to skirt 36 for receiving air discharged by blower 27 and for supplying the air discharged by blower 27 into a different adjacent vehicle.
As best shown in FIG. 5, air is returned from adjacent vehicles for recirculation through recirculation hoses 47, 48 which surround the distribution hoses 43, 45, respectively, and which are connected to skirts 49, 50, respectively. Skirts 49, 50 are welded or otherwise affixed to the top of casing 11 and surround respective casing openings that are in substantial alignment with skirts 35, 36. Collection nozzles 51, 52 are connected, respectively, to the free ends of recirculation hoses 47, 48 and surround, respectively distribution nozzles 44, 46, thereby forming elongate and relatively narrow air ring-like collection openings communicating with the respective interiors of hoses 47, 48. It is desirable to form nozzles 51, 52 ofa resilient material in order that they may be secured in place. without damage thereto, by placing such a nozzle between the top of a window and the window frame of a vehicle and raising the window to apply a squeezing action to the upper and lower sides of the nozzle.
From the foregoing, it will be apparent that air for.recirculation purposes is returned to unit 10 from an adjacent vehicle through said elongate ring-like collection opening a via a passageway formed between the exterior surface of distribution hose 43 and the interior surface'of recirculation hose 47 as shown in FIG. 5 in which the air supplied to an adjacent vehicle is indicated by a solid arrow and the recirculation air returned to unit 10 is indicated by phantom line arrows. When the air returned from adjacent vehicles is returned to unit 10, it is again passed through evaporator coil 13 into chamber 37 and is thereby either re-cooled and/or re-heated. Thereafter, the air flow cycle is repeated and blowers 26, 27 supply such re-cooled and- /or re-heated air to adjacent vehicles through distribution hoses 43, 45 in the manner described heretofore.
Since recirculated air from different adjacent vehicles thus passes through a single coil 13 and a single chamber 37 before re-entry into blowers 26, 27, a difficult problem is presented because, as noted heretofore. it is desirable to avoid mixing of the air returned from different vehicles. In accordance with the invention. such mixing is effectively avoided by provision of individual flow paths forthe return air which are disposed outside of rather than within chamber 37.
As best shown in FIGS. 3-5, as the individual streams of recirculation air enter the top of casing 11 from recirculation hoses 47, 48, respectively, they are caused to remain individual streams by provision of a wall 53 extending across the entire width of casing 11 and downwardly from its top to the top of blower enclosure 28, and by another wall 54 extending from the midpoint of wall 53 across the top 40 of chamber 37 to one corner of evaporator coil 13.
A return air chamber 55 receives the returned or recirculating air and distributes it across the side of evaporator coil 13 so that it can be drawn through the coil and into chamber 37 by squirrel cage blowers 26, 27. Chamber 55 comprises end wall 56, side walls 57, 58 and top and bottom walls, 59, 60, respectively, and a connecting wall 61 by which chamber 55 is secured to casing 11. Additionally, chamber 55 includes a partition wall 62 extending horizontally between side walls 57, 58 thereby dividing chamber 55 into separated upper and lower chamber portions.
The central portion of connecting wall 61 forms an opening so that chamber 55 is in communication with the space between the top of casing 11 and the top of coil 13 and also with the spaces between opposite sides of coil 13 and the side walls of casing 11. The upper and lower margins of said opening are defined along the juncture between connecting wall 61 and top wall 59 and bottom wall 60.
Between bottom wall 60 and partition wall 62, connecting wall 61 extends inwardly beyond side wall 58 to side of coil 13. However, between partition wall 62 and top wall 59, the margin of said opening is at the juncture between wall 61 and wall 58.
Similarly, the margin of said opening is at the junctiire between wall 61 and wall 57 between partition wall 62 and bottom wall 60, but, between partition wall 62 and top wall 59, the margin of the opening is along the inner edge of connecting wall 61 which extends inwardly beyond side wall 57 to the side of evaporator coil 13.
Thus, the opening in connecting wall 61 is divided into upper 55a and lower 55b portions each rectangular in shape and relatively offset from one another along partition wall 62 which forms a margin common to both opening portions. By virtue of this arrangement, air returned to unit via return hose 47 enters into casing 11 between the top thereof and the top of blower enclosure 28 and top of chamber 37. Since wall 61 extends inwardly to the edge of coil 13 between top wall 59 and partition wall 62 of chamber 55, such air cannot enter the upper portion 55a of chamber 55 and therefore flows downwardly between the side wall of casing 11 and chamber wall 38 and then enters into the lower portion of chamber 55 below partition wall 62. Similarly, air returned to unit 10 via hose 48 is prevented from entering the lower portion 55b of chamber 55 and instead such air enters the upper portion 554! of chamber 55 after flowing across the top 40 of chamber 37 and across the top of evaporator coil 13 and along the side thereof above partition wall 62.
Louver openings 63, 64 in wall 56 communicate. re spectively, with upper chamber portion 551! andlower chamber portion 55b.
A suitable control 65 projects outwardly from casing 11 for selectively rendering unit 10 either operative or inoperative. Control 65 is electrically connected to a driving motor for compressor 12 and/or to heater element 42 in a known manner that is not essential to an understanding of the present invention and, accordingly, such connection is not shown. If desired, a suit able switch (not shown) may be provided to selectively connect the compressor motor with control 65 and to simultaneously disconnect heater element 42 therefrom, or to selectively connect heater element 42 to and simultaneously disconnect the compressor motor from control 65.
In operation with the controls set to render the refrigeration system operative, air is cooled in the manner described heretofore as it is drawn through evaporator coil 13 into chamber 37 by blowers 26, 27. If the air is cooled below its saturation temperature, condensation of moisture will occur and such moisture will fall to floor 41 of chamber 37 and is removed therefrom by a suitable drain, not shown. Thus. cooled air of reduced moisture content is received into blowers 26, 27 which deliver the cooled air to adjacent vehicles via distribution hoses 42, 45 and their respective distribution nozzles 44, 46 and the air pressure within adjacent vehicles is thereby increased to a value slightly above the ambient atmosphereic pressure. Thus, entry of undesirable bugs and insects in inhibited, as well as entry of warm embient air, and some of the cool air is thereby lost due to leakage from the vehicle to the ambient atmosphere.
Warmer air within the vehicles is collected by collection nozzles 51, 52 and returned to unit 10 for cooling and recirculation via recirculation hoses 47, 48, respectively. As air is returned into casing 11, air from hose 47 is prevented from mixing with air returned by hose 48 by divider wall 54 at the top of chamber 37. And air from hose 47 flows'into lower chamber portion 55b,
while that from hose 48 flows into upper chamber portion 551:, as noted above.
As blowers 26, 27 draw air from the upper and lower chamber portions 55a, 55b, they also draw into the system air from the ambient atmosphere through openings 63, 64. A strong suctional effect is established at the blowers inlets which are respectively aligned with upper and lower chamber portions 55a, 55b. Accordingly, air drawn through evaporator coil 13 from upper chamber portion 550 flows tlhrough chamber 37 and directly into blower 27. Similarly, air from lower chamber portion 55b, after passing through coil 13, flows directly into blower 26.
The entire air flow cycle is then repeated and the recooled air returned from the adjacent vehicles is again supplied to and returned from such vehicles in the above described manner.
When heated air is required, the selective control switch is manipulated to energize heating element 42 and to render inoperative compressor 12. Supply of and recirculation of air to and from adjacent vehicles is effected by blowers 26, 27 in the above described manner except that air is heated as is passes through chamber 37 and evaporator coil 13 now provides no cooling action.
Thus, additional moisture is removed from the air with each recirculation thereof during operation of the refrigeration system portion of the device. Also, improved performance and efficiencies are realized, irre spective of whether the device: is operating on a cooling or a heating cycle, from provision of air recirculation means. particularly when this coupled with the insulating effect provided by coaxial supply and return passageways.
In the foregoing description, references to either blower 26 or 27 are intended to include a complete blower unit wherein a squirrel cage rotatable unit is housed within a customary blower housing or scroll casing having suitable discharge and inlet openings. However, the present invention comtemplates a modifled embodiment of the blower structure, FIG. 7, the use of which results in achievement of further improve ments and advantages such as simplified structure, reduced manufacturing costs and rapid heat transfer and temperature stabilization.
in accordance with this aspect of the invention, only very simple structural components are required in provision of suitable housings for the rotatable squirrel cages of both blowers 26, 27. The end walls of a single casing for both blowers 26, 27 are constructed of sheet metal and each wall requires only a pair of spaced openings therein, respectively for air inlets to the squirrel cage rotors and for drive shaft therefor. Thus, walls 29, 53 constitute such end walls.
Each blower 26, 27 requires side walls defining a spiral or scroll that forms a discharge opening. As shown in FIG. 7, a single casing wall provides such scrolls and openings for both blowers. Wall 70 is formed of metal such as aluminum that is readily cast by known casting techniques into desired shapes. Wall 70 extends downwardly and then curves inwardly to the right toward the upper margin of squirrel cage of blower 26 which is then encompassed in said wall which then curves upwardly to the left to form a spiral or scroll portion following which it is r'eversely curved and then extends upwardly, spaced from and substantially parallel to its downwardly extending portion. Near the juncture of the upwardly curved and the upwardly extending portions, wall 70 is bifurcated with the right hand branch thereof curving upwardly and then downwardly to encompass the squirrel cage of blower 27, finally extending upwardly and spaced from and substantially parallel to the above mentioned upwardly-extending portion thereof Additionally. near the juncture between the above mentioned reversely curved and spiral or scroll portions, wall 70 includes a second bifurcation with the upper branch thereof curving to the right and upwardly to form a spiral or scroll portion for blower 27 and terminating with an upwardly extending portion spaced from and substantially parallel to the upwardly extending portion of the first mentioned branch.
Thus. cast wall 70 encompasses and defines spaced apart cavities for receiving the respective squirrel cages of blowers 26, 27 and also defines two passageways disposedat opposite sides of the cavity with each of said passageways in communication with one of said cagereceiving cavities.
Thus the casing elements are mechanically and structurally simple and are easily manufactured at minimum manufacturing cost. Additionally, wall 70 may be relatively thin so that heat transfer and/or dissipation is rapid. Furthermore. this construction serves to stabilize temperatures and minimize the effect of any temperature difference that may exist between the top and the bottom of evaporator coil 13.
While particular embodiments of the invention have been shown and described, it will be obvious that various changes and modifications may be made without departing from the invention. and it is intended in the appended claims to cover all such changes and modifications that fall within the true spirit and scope of the invention.
What is claimed is:
1. In a self-contained air-conditioning unit for supplying and re-circulating conditioned air to and from a pair of adjacent enclosures, the combination comprising a single heat exchanger means having spaced apart opposite faces and having walls defining a plurality of parallel passageways extending between said faces.
a wall structure spaced apart from one of said faces and defining first and second blower-inlet means spaced apart from each other, and
means including first and second blower means conducting and maintaining two discrete flows of fluid without intermixing thereof from said heat exchanger means into said individual blower-inlet means and additionally including other walls defining a pair of spaced apart discrete passageways each connected to the other of said faces and in fluid flow relationship with certain of said parallel passageways for receiving fluid recirculated from one of said enclosures one of said inlet means being positioned in alignment with said certain passageways.
2. Combination according to claim 1 and additionally including selectively operable heating means positioned within said single chamber.
3. Combination according to claim 1 and additionally including an opening in said other walls and in fluid communication with said pair of discrete passageways for admitting ambient air thereinto.
4. Combination according to claim 1 and additionally including first conduit means connected to one of said blower means and encompassed by second conduit means connected to the discrete passageway that is aligned with the inlet of said one blower means.