US3415073A

US3415073A - Roof-type air conditioning system

Info

Publication number: US3415073A
Application number: US651931A
Authority: US
Inventors: Walter D Ammons
Original assignee: Walter D. Ammons
Current assignee: WALTER D AMMONS
Priority date: 1967-06-12
Filing date: 1967-06-12
Publication date: 1968-12-10
Anticipated expiration: 1985-12-10

Description

Dec. 10, 1968 w. D. AMMONS ROOF-TYPE AIR CONDITIONING SYSTEM 2 Sheets-Sheet l Filed June 12, 1967 WALTER 0. AMMONS flamfflwa VIII ATTOR EY Dec. 10, 1968 w. D. AMMONS 3,415,073

ROOF-TYPE AIR CONDITIONING SYSTEM FIG.4

ed June 12, 1967 2 Sheets-Sheet 2 6 0 INVENTOR.

WALTER D. AMMONS ATTORN Y United States Patent 3,415,073 ROOF-TYPE AIR CONDITIONING SYSTEM Walter D. Ammons, 1165 N. Rio Vista Blvd., Fort Lauderdale, Fla. 33301 Filed June 12, 1967, Ser. No. 651,931 13 Claims. (Cl. 62-259) ABSTRACT OF THE DISCLOSURE An elongated base for an air conditioning system adapted for fixed level positioning upon a roof top, comprising an elongated bottomless insulating jacket fixedly supported upon the base to enclose a major portion thereof including various units carried thereby, an elongated bottomless shroud removably secured to the roof top in a fixed position, enclosing the jacket in spaced relation thereto to provide therebetween an air space through which air may freely circulate, and, carried on the base, a unitary air conditioning system which includes a horizontal duct for delivery of blower-driven heated air through a side opening in the shroud near one end thereof. Two vertical ducts near the opposite end of the shroud are also extended downwardly through the base and roof top, one to supply air to a room therebelow and the other to return air upwardly therefrom. Also mounted on the base adjacent the upper ends of both vertical ducts is an evaporator together with an associated blower means which propels cooled air downwardly through the supply duct into the room therebelow, the lower end portions of both vertical ducts terminating at or about the ceiling level of the room into which cooled air is delivered. Grilles are also affixed within the lower end portions of the vertical ducts within one of which is mounted a switch mechanism for controlling operation of the air conditioning system. The mounting of both grilles is such as to leave the head room therebelow substantially intact.

This invention relates to an air conditioning system which is particularly adapted for overhead mounting, as for example atop of a room ceiling or roof. To qualify for such use, it is important that the entire air conditioning system be unitary and accessible for service; that it require but a single operating connection, i.e., to a power source, when installed; that the apparatus in its entirety be light so as to reduce to a minimum the load which is imposed on the ceiling or roof structure; that the unitary air conditioning apparatus be compact so as to occupy only the minimum of roof space, wherever installed, and with little or no reduction of head room thereunder; and that the apparatus in its entirely be fixedly secured by means which may be speedily applied or removed whenever the occasion so demands. Factors such as these adapt the present air conditioning system for use in places where the demand exists but which cannot accept the usual apparatus, because of weight, size or complications in excess of limitations imposed by the surrounding conditions. Examples of such places benefiting from an air conditioning system, but unable to accommodate the usual equipment therefor, are many cabins in yachts and boats generally, homes and buildings, either stationary or mobile, having inside rooms with no available spaces for floor or walbmounting of such mechanisms, and other places where like conditions exist. In each such instance, there may be, and often is, attic or roof space available for mounting of a unitary air conditioning system, provided that it be specially designed for such purpose as hereinafter described. It is with the production of such an air condi- 3,415,073 Patented Dec. 10, 1968 "ice tioning system, adaptable to the conditions mentioned, that the present invention is primarily concerned.

These and other objects and purposes to be served by my invention will appear more fully from the ensuing description, taken in conjunction with the accompanying drawings which illustrate a preferred embodiment thereof in the manner following:

FIGURE 1 is a view in horizontal section, taken on line 1-1 of FIG. 2, showing a top plan view of the unitary air conditioning system enclosed on three sides by the insulating jacket therefor;

FIG. 2 is a view in vertical section, taken on line 2-2 of FIG. 1, showing in elevation one side of the unitary air conditioning system within the enclosing jacket;

FIG. 3 is a view in vertical section, taken on line 3-3 of FIG. 1, showing in elevation the opposite side of the unitary air conditioning system;

FIG. 4 is a view in vertical section, taken on line 4-4 of FIG. 2, showing in elevation portions of the evaporator, plenum chamber, blowers therefor, and supply duct of the unitary air conditioning system;

FIG. 5 is an exploded perspective view, partly in section, showing in spaced relation the covering shroud, insulating jacket, apparatus base, vertical air supply and return ducts, a section of roof structure prepared for reception therethrou-gh of the ducts, and grilles to be affixed to the discharge end portions thereof at or about the ceiling level of the room immediately below the roof structure;

FIG. 6 is a view in sectional detail, taken on line 6-6 of FIG. 1, showing the delivery end of the horizontal duct in relation to the jacket and enclosing shroud therefor;

FIG. 7 is an enlarged fragmentary detail in section, taken on line 2-2 of FIG. 1, showing portions of the base, supply duct, shroud and jacket;

FIG. 8 is a diagram of an electrical system which may be employed in connection with the present air conditioning system; and

FIG. 9 is an enlarged fragmentary view in transverse section through the return duct, grid and filter therein, showing in elevation a switch mechanism which may be incorporated in the electrical system of FIG. 8.

Referring first of all to FIG. 5, a section of crowned roof R is therein shown to be supported upon arched cross beams 10 such as are commonly used in cabins of yachts, house trailers, etc. Usually such a roof is relatively narrow, requiring that any unitary air conditioning system designed for mounting thereon be also narrow in one direction. This type of roof has been chosen as illustrative of the special conditions which are regularly encountered by any air conditioning system proposed for roof-mounting. Through such a roof top, between adjacent beams 10, I prov de a rair of ide by side elongated openings 11 and 12, one to receive therethrough an air supply duct 13 and the other, somewhat wider, to receive an air return duct 14. Both of these ducts which fit closely within the openings provided therefor are disposed vertically with open ends at their bottoms terminating at or about the level of the under faces of the beams 10 to which a liner 15 may be affixed to provide a ceiling for a cabin or room therebelow (FIG. 1). A grille 16 is fixedly applied to the open discharge end of the suppy duct 13 and another grille 17 to the open inlet end of the return duct 14. Each grille comprises a frame F having an out-turned. facing 18 adapted to lap the ceiling 15 adjacent the opening provided therefor, to engage therewith whereby the grille in its entirety, save for the facing, may be accommodated within the narrow horizontal space between the roof top and the ceiling without further depending therefrom to reduce 3 the head room therebelow (FIG. 2). The supply grille 16 comprises adjustable cross vanes by which to deflect air discharged therethrough away from the adjacent return grille 17 and toward the horizontal. The return grille is in the form of a grid removably carried in its frame F, as will be noted further hereinafter.

The unitary air conditioning system herein to be described is carried upon a horizontal base B which is elongated to provide a structure whose width is perhaps half its length. This base may conveniently be produced from sheet metal of heavy gauge, such as aluminum or an aluminum alloy. It is formed with an upstanding peripheral flange 20 which furnishes ample reinforcement therefor, also with two elongated openings 21 and 22 having upstanding

peripheral flanges

23 and 24, respectively, both openings being the same in size and shape as the roof openings 11 and 12 so as to register therewith, their long dimensions being extended crosswise of the base for nearly its full width (FIG. 5). The two

vertical ducts

13 and 14 are also rectangular in cross section, and considerably elongated in one direction so as to extend lengthwise of the openings 11 and 12 for substantially the full width of the base. Each of these vertically extended ducts is desirably accommodated between adjacent pairs of beams 10, and in mutually spaced relation to each other (FIG. 2).

A shoulder 25 (FIG. 7) is fixedly extended outwardly from all four walls of each duct at a point which is relatively close to its top, adapted to rest upon a spread of caulking material 26 applied to the upper face of the roof top adjacent each duct opening therethrough, whereby to establish sealing engagement therewith. The upper end portion of each duct is protruded upwardly through the base B to terminate a short distance thereabove where a collar 27 is fixedly applied thereto in spaced relation to the shoulder 25 therebelow. Each collar is adapted to engage the top face of the base, thereby coacting with its associated shoulder 25 therebelow to lock the duct firmly to the base. Fasteners 28 are extended vertically through the base and through registering openings in each collar 27 and shoulder 25 therebelow to complete the securement of each duct to the base. The term fasteners as used herein refers to screws, bolts, rivets, or equivalent means, whichever may be best suited for the immediate purpose in view.

Fitted around the base are the upstanding walls of an elongated, bottomless, three-sided insulating jacket I, closed at its top and one end, its opposite end being open. The walls of this jacket extend closely around the base end which is proximate to the supply duct opening 11 and along opposite sides of the base for the major part of its length. To secure the jacket fixedly in place, fasteners 29 are extended through the jacket at spaced points close to its bottom edges to traverse openings in the base peripheral flange 20, whereby to support the jacket with its bottom edges spaced above the roof top (FIG. 7). This jacket desirably comprises an exterior sheet 30 of aluminum or the like adapted to support a relatively thick lining 31 of fiberglass, thereby to provide a unitary structure which is sturdy, waterproof, and high in thermal and acoustical values. Also mounted upon the roof top is an elongated shroud S of fiberglass or the like which completely encloses the jacket and base. The top of this shroud is shown as slightly arched crosswise and bowed endwise (FIGS. 2 and 4) to provide a space between its top and that of the jacket in communication with other spaces extending continuously around the sides and ends of the jacket whereby to establish an air curtain between the jacket and shroud. The lower edge portions of the shroud at its four corners depend downwardly a sufiicient distance to provide feet 32 which are fixedly secured to the roof top by fasteners 33 extended therethrough and into upstanding brackets 34 which are anchored to the roof top (FIG. 7).

Air is free to enter into the shroud at roof level between its feet 32, and also at one end of the shroud through which is formed a large louvered opening 35 (FIG. 5) oppositely of the open end of the jacket J therewithin. TlWO further louvered

openings

36 and 37 of generous size are also provided in opposite side walls of the shroud (FIG. 4) at points proximate to its end opening 35, the former serving as an additional air inlet opening and the latter for eduction of heated air from within the shroud generated during operation of the air conditioning system.

The base B is designed for level mounting upon a roof top R which is often crowned crosswise and occasionally arched endwise. This poses a special problem which is met by providing brackets 38 upstanding from the roof top to which they are anchored, four or more such brackets being suggested, one near each corner of the base. Fasteners 39 which traverse these brackets and the jacket near its lower edges engage the peripheral flange 20 of the base whereby to furnish support therefor (FIG. 7). The minimum elevation at which the base can be supported is determined by that of the roof crown whereon the base is desirably rested. This point of support is preferably close to the longitudinal center of the base, but where obstructions on the roof top prevent such positioning, the base mounting may be shifted to an off-center position. If desired, one or more spacer shims (not shown) of any suitable material may be Ifitted beneath the base at points adjacent its longitudinal edges to provide thereat any needed support therefor. The number of such shims in superposed relation determines the height at which the base is supported at each point. While this number will vary according to the curvature of the roof crown, the number of superposed shims may also be varied, as needed, to provide for the base a mounting which is level both crosswise and endwise. It will be noted that the jacket J which is fitted over the base derives a fixed support therefrom which is important for maintenance of a predetermined clearance between the jacket walls and top and the confronting surfaces of the various units of the air conditioning system which are fixedly mounted on the base, as will presently appear. The shroud, on the other hand, is mounted directly on the roof top and in spaced relation to the jacket, this relationship being assured by proper positioning of the several brackets 34 to which the shroud is anchored (FIG. 7).

Lengthwise of the base B, the operating units of the air conditioning system are so arranged as to provide two thermally different end zones which are separated by an angled partition P extending crosswise between opposite walls of the jacket. The relatively hot zone is occupied by a fixedly mounted motor-compressor M which is positioned at one corner of the base adjacent the shroud end and side openings 35 and 36 (FIGS. 1, 4 and 5). In the same zone it will also be convenient to mount an upstanding water-proof box T containing and protecting all terminals of the wiring in the electrical system employed. A system of fins and/or coils comprised in a condenser C which upstands from a drain pan 41 therefor is also located in this same zone adjacent the base opening 22 and proximate to the compressor M. An insulating mat 42 of rubber or the like is carried on the base to underlie this pan and prevent sweating. This mat which extends past the openings 21 and 22 is open thereat to receive therethrough the upper end portions of the vertical ducts 13 and 14 (FIG. 2). The tops of the box T and condenser C are substantially co-level and somewhat lower than that of the motor-compressor M, and also well below those of the jacket and shroud, whereby to provide space for reception of a horizontal duct D leading from the condenser C. This duct which lies in part beyond the open end of the jacket I (FIGS. 1 and 2) extends through the space between opposite walls thereof with its delivery end positioned adjacent the shroud eduction opening 37 where it is fixedly held upon the tops of the condenser and terminal box. To occupy this position, a wall of the jacket at its open end is edge-notched at 53 (FIG. 5) to receive therein aportion of the duct D adjacent its widened discharge end.

The contour of the discharge duct -D is right angular in a horizontal plane, having a hypotenuse wall 43 angled from its wide discharge end and disposed to one side of the compressor M of higher elevation (FIG. 1) as it continues on to join one end of its elongated base wall 44 which is extended transversely for nearly the full distance between opposite sides of the jacket. Two sideby-side inlet openings 45 to this duct are provided in its base wall, each opposite the discharge end of a,dual rotary blower X with which it is tightly connected as by means of bolts 46 ('FIG. 2). These two blowers which are combined into a single unit, together with an operating motor 47 therefor, are supported by the condenser C to remain suspended adjacent its side which is remote from the compressor M, at an elevation well above the base B and directly above the open end of the vertical air return duct 14 extending therethrough (FIG. 2). Heated air from the condenser is admitted into the dual air blowers through circular inlets 48 in their end walls which are amply spaced from the proximate walls of the jacket I to permit freecirculation of air for this purpose. While the two blowers X are unequally distant from the delivery end of the duct D, the one adjacent its narrow end discharges air straight toward its hypotenuse wall 43 at a relatively near point to be deflected thereby for travel endwise of the duct through a relatively long distance toward the open end thereof, whereas the other blower from which air must travel a further distance before striking the hypotenuse wall 43 to be deflected thereby, is required to advance the air therefrom through only a relatively short distance to its point of eduction through the shroud opening 37. In effect, these are balancing factors tending to equalize the loads imposed upon the two blowers and also the volumes of the air streams issuing therefrom.

The motor-compressor, condenser, air discharge duct therefor, and motor-driven blowers which propel the air through the duct, are the major units accommodated within the hot air zone which extends throughout one end portion of the base. Separating this zone from an adjacent cold air zone in the opposite end portion of the base, is the partition P which extends crosswise between opposite sides of the jacket and from its top down to the base to provide thereat an effective thermal barrier. Support for the partition is furnished at its top and bottom, its ends being free of the jacket. This partition in its upper portion overlies a vertical system of coils and/ or fins forming an evaporator E which upstands from the base strip 49 lying between the openings 21 and 22 therein. Underlying the evaporator is a drain pan 50 which rests upon the mat 42 at an elevation slightly above the level of the pan 41 and disposed below the condenser C (FIG. 2). Condensate accumulating to unequal elevations in these pans is free to drain from the higher into the lower through a connecting tube 51 and from the latter as through a short flexible drain tube 52 for discharge upon the roof top at any desired point thereupon (FIG. 1).

Since the blower unit X suspended from one side of the condenser is disposed over the base opening 22, and rather close to the evaporator E, the partition P is twice angled to provide (1) a zigzag contour whose upper section overlies the evaporator top where it is secured thereto, (2) an intermediate section which depends therefrom substantially vertically through the relatively narrow space between the evaporator and the blower unit X, and (3) a lower section which extends obliquely over the base opening 22 to a point therebeyond adjacent the condenser where it is secured fixedly to the base. The space thus defined by the zigzag contour of thepartition on its under side adjacent the base lies oppositely of the air return duct 14 and in communication therewith. Incoming air at room temperature rising through this duct is accordingly free to circulate upwardly throughout this space and be deflected laterally by the obliquely disposed lower section of the partition to move horizontally between the fins and/or coils of the evaporator, thereby to become chilled before passing on into the larger space on the opposite side of the evaporator where a dual blower unit Y is positioned to draw the cooled air into its axial circular inlets 54. This blower unit which is desirably a duplicate of the blower unit X is equipped with a motor 55 whose axis is coaxial with that of the rotors-comprised in the two blowers of the unit. A mounting at 56 for the blower unit Y is provided upon an elongated plenum chamber Z with which the dual blowers are in communication. This plenum chamber, which also overlies the upper open end of the air supply duct 13 to communicate therewith, extends crosswise of the base for nearly its full width. Its bottom edges engage the mat 42 in which position it is firmly held by fasteners appropriate for the purpose.

The major units of the air conditioning system comprise the motor-cornpressor M, the condenser C, and the evaporator E, as herein shown and described. A communicating system between these units: comprises a tube 57 (FIG. 3) leading from the compressor adjacent its base to the condenser near its top, a tube 58 extending between the base portions of the condenser and evaporator having an associated capillary tube connected therewith, and a suction tube 59 interconnecting top portions of the evaporator and compressor. With the motor-compressor and two blower units in operation, coolant employed with the system is caused to circulate therethrough to produce a refrigerated condition in the evaporator unit in the manner well known to air conditioning systems of the present time.

A common problem in connection with air conditioning systems, particularly when used where high humidity prevails, is sweating. This usually manifests itself at or near the discharge end of the air supply duct 13. This difliculty is obviated in the present apparatus by optionally providing in this duct a lining 60 of fiberglass or the like (FIG. 7) which is high in insulation value, plus use at the discharge end of this duct of a non-sweating type of grille. The conditions here are similar to those where such a grille is mounted at the discharge end of an air supply duct which opens out through the wall of a cabinet housing an air conditioning system. Here the horizontal ceiling 15 corresponds to a cabinet wall, usually vertical, where an air supply duct terminating thereat is fitted with a grille of the kind referred to. One such grille suitable for use herein to prevent formation of condensate at the point of cooled air discharge into a room, is disclosed in my application for patent filed Nov. 7, 1966 under Ser. No. 600,325 wherein appears a full discussion of the factors involved in preventing accumulation and dripping of condensation thereat.

The electrical system employed utilizes a controlling switch mechanism W with operating means therefor all carried within a U-shaped frame 61 attached interiorly to the frame F of the grille in the air return duct 14. Reference to FIG. 9 shows the switch mechanism as wholly accommodated within that duct and frame at one end wall thereof. A cut-out in one end of the grid 17 provides space at one end thereof for accommodation of the lower part of the switch mechanism which is concealed by a dialed face plate 62 thereunder. A rotatable wing knob 64 carried on the under side of the face plate, is operable through a vertical connection and parts associated therewith, to control the compressor whereby to vary the output of chilled air from the air conditioning system. The switch plate and frame facing 18 are substantially co-level whereby it is only the small knob control depending beneath the face plate which occupies any space below the level of the ceiling 15, and this need be only a fraction of an inch or so.

The grid 17 is disposed to lie wholly within the frame F therefor, being supported therein upon a plurality of turn-buttons 65, each pivoted upon the under face of the frame facing 18 to swing in a horizontal plane. The upper face of each button, when rotatively adjusted for the purpose, is adapted to engage an under face of a peripheral strip comprised in the grid to afford support thereto. To remove the grid, the buttons are adjusted to non-engaging positions, all interference being then removed to withdrawal of the grid downwardly from its frame. When in use, a filter 66, the same in size and contour as the grid, is rested thereupon to screen out particles from the air rising through the return duct 14 for recirculation in response to operation of the various units hereinbefore described.

A suggestive wiring for the electrical systems is diagrammed in FIG. 8. In the case of a boat, for example, the source of current may be either aboard or ashore. If connection be made to a dock current, then the boat wiring system usually includes a fitting on deck or elsewhere for removable attachment thereto of a power line from a current source ashore; otherwise connection is made with a line from the boats own power plant.

Referring again to FIG. 8, a current supply line 68 in the electrical system leads to the switch mechanism W with which is associated a thermostat 69 from which is extended a main line 70 to an overload circuit breaker 71. Here connection is made at 74 with a relay 75 from which a line 76 is extended to the running pole r of the compressor motor M which may be of the 110 volt, 60 cycle, single phase type. A further connection 77 leads from its starting pole s back to the relay which, through another line 78, is also in connection with a ground line 79. From the circuit breaker 71 a line 80 is extended to a common pole c of the motor M. Two capacitors 81 and 82 are also provided, the first to serve when the compressor and blowers are being started, and the second when they are in operation. The starting capacitor 81 is connected through the lines 74 and 77 with the starting pole s of the compressor motor, and from the running pole r thereof the line 76 leads to the relay 75. The running capacitor 82, on the other hand, is connected by the line 85 and through the pole s with the opposite pole r" of the compressor motor M. From the switch thermostat 69 two lines 86 are extended, one to each of the blower units X and Y, and from these units other lines 87 are carried to the ground line 79, thereby completing the electrical circuit.

The electrical system is both simple and ample to meet all requirements. It utilizes a single switch mechanism to control current for starting and stopping of the compressor motor and both blower units whereby to assure dependable operation of the air conditioning system, when and as desired. The overload protector and capacitors are grouped together within the terminal box T, and the connections therebetween, including those leading to and from the switch unit, are fitted into the narrow space between one side wall of the jacket I and the proximate ends of the two blower units X and Y, the evaporator E, and the condenser C. The current supply line, whether leading from a power source ashore or aboard, may be extended through the closed space between the roof top R, the ceiling 15, and one pair of beams 10, entering into the duct 14 through an insulating bushing 90 which is fitted through a wall thereof to establish connection with the switch unit W.

It should be apparent that the air conditioning system herein disclosed economizes both in size and weight, that it eifectively insulates both thermally and acoustically where most needed, and that its operating units are readily accessible for service whenever desired. As to size, a shroud having outside dimensions of 15" high, 21" wide, and 42" long is adequate for accommodation of an air conditioning system utilizing 1725 watts when delivering 10,500 B.t.u. The total weight is approximately lbs. The operating units which are employed, as well as their disposition, are factors contributing to minimization of the space required. They occupy in-line positions upon an elongated base, starting with a compressor at one end portion which is heated and ending with a plenum chamber at the other end which is chilled, and with an insulating partition therebetween which is vertically off-set to extend obliquely between a hot air blower unit X positioned directly over an air return duct therebelowan overlapping arrangement in which space, both vertical and horizontal, is conserved.

A roof-type air conditioning system is subjected to maximum exposure, yet in the present apparatus ample protection against weather is afforded to the base-mounted units, including the jacket, which are carried above the roof top level. The jacket which insulates these several units against off-normal thermal forces is itself protected thermally and otherwise by the weather-proof shroud which additionally encloses the jacket, the base, and all units carried thereon. Between the walls of the jacket and shroud the air curtain which augments the themal insulation between the operating units and the outside atmosphere is itself replaced from time to time by fresh air from the outside, in response to natural forces currently prevailing. These beneficial results are achieved along with (l) a low height for the apparatus which is mounted upon the roof top, and (2) a short vertical travel of the chilled air downwardly into a cabin or room therebelow, and all without diminution of the head room therein.

I claim:

1. For mounting upon a roof top, an elongated base whereon is carried a unitary air conditioning system comprising, in one end portion of the base, a compressor, a condenser, a horizontal duct extending crosswise over the base for eduction of heated air therethrough, and a first rotary blower unit associated with the compresser and condenser, having its axis horizontally disposed and its discharge outlet in communication with the horizontal duct to propel air therethrough into the outside atmosphere; and in the opposite end portion of the base where two spaced-apart openings are formed therethrough, a vertical duct extended downwardly through each base opening and in communication with a room below the roof top, an evaporator upstanding from the base between the openings therethrough, and a second rotary blower unit associated with the evaporator having its discharge outlet in communication with one of the vertical ducts to propel cooled air downwardly therethrough into the room therebelow and to induce return of room-temperature air rising through the other vertical duct for delivery into confined space adjacent the evaporator, the first blower unit being positioned over the base directly above the upper open end of the vertical return duct, and a thermal partition positioned crosswise of the base to separate the two end portions thereof, the partition being extended substantially vertically between the evaporator and the first blower unit and obliquely below the latter and over the upper open end of the vertical return duct whereby to deflect air rising therefrom toward and through the evaporator.

2. A unitary air conditioning system as specified in claim 1 wherein each blower unit comprises a motor coaxially arranged between two rotors having separate discharge outlets, and wherein an elongated plenum chamber is provided to receive cooled air from both discharge outlets of one blower unit, the plenum chamber being commensurate in size with that of the vertical duct through which the cooled air is propelled downwardly and with which it is in communication.

3. A unitary air conditioning system as specified in claim 1 wherein the first blower unit is of dual nature with a motor arranged coaxially between two rotors having separate discharge outlets in spaced side-by-side relation, and wherein two walls of the horizontal duct are diverged away from each other toward its delivery end, there being two side-by-side openings formed in one such wall through which communication is established with the two discharge outlets of the blower unit, the diverging duct wall opposite thereto receiving impact of the two air streams advancing unequal distances from the discharge outlets of the blower unit whereby to deflect each stream toward the delivery end of the duct, the distance of air travel, after deflection, being greater for the air stream which, before deflection, traveled less, and vice versa, thereby tending to equalize the flow of the two air streams passing through the duct for eduction into outside atmosphere.

4. An air conditioning system as specified in claim 1 wherein an electrical system interconnects a current source with the two blower units for concurrent operation, and a control switch mechanism therefor is affixed to one of the vertical ducts close to its lower open end to be accessible for manipulation from within the room therebelow.

5. A unitary air conditioning system as specified in claim 1 wherein an electrical system interconnects a current source with the two blower units for concurrent operation, a grid is removably fitted into the lower end portion of the return duct through which air rising from the room is delivered into cooled space thereabove, a control switch mechanism for the electrical system is aflixed to a wall of the return duct at a point above the grid, and means for operating the switch mechanism depends therefrom through the grid to be accessible for manipulation upon the under side thereof.

6. A unitary air conditioning system as specified in claim 1 wherein the lower ends of the vertical ducts terminate at a common level slightly above that of a ceiling carried on the under side of the roof structure, wherein framed grilles with flanged facings are fixedly applied to the two ducts in the lower end portions thereof to lie wholly therewithin, the flanged facings then lapping the adjacent peripheral portions of the ceiling whereby to leave intact the head room therebelow, and wherein the grille afiixed to the air-delivery duct is equipped with a plurality of adjustable vanes adapted to deflect air issuing therethrough away from the adjacent return grille and toward the horizontal.

7. A unitary air conditioning system as specified in claim 1 wherein the compressor is relatively tall and located closer to the end of the base than is the condenser which is relatively short to leave between its top and the top of an insulating jacket thereabove a space of appreciable height extending crosswise of the base for substantially its full width, and wherein the horizontal duct is supported in place within the space above the condenser adjacent the compressor, the latter in its upper end portion being extended upwardly beyond the horizontal duct and to one side thereof.

8. A unitary air conditioning system as specified in claim 1 wherein the two openings through the base are elongated to extend crosswise thereof and are spaced apart sufliciently to leave therebetween an elongated strip whereon the evaporator is mounted, the evaporator being elongated and narrow in conformity with the contour of the base strip whereby to extend crosswise of the base for the major portion of its width, and the vertical ducts being of substantially the same cross-sectional size and shape as the base openings through which they are fitted, whereby to extend crosswise of the base for the major portion of its width, the arrangement being such that the evaporator upstanding from the base strip between the duct openings stands in the movement path of air rising through one duct for delivery at the base of the evaporator, requiring that the air then advance horizontally therethrough enroute to the blower unit by which the air, then chilled, is downwardly propelled through the other duct.

9. For mounting upon a roof top, an elongated base whereon a unitary air conditioning system is carried, means for securing the base fixedly to the roof top, an elongated three-sided, bottomless, insulating jacket open at one end, adapted to be supported upon the base and fitted around one end and along opposite sides thereof for a major portion of their lengths, and over a unitary air conditioning system thereon, an elongated bottomless shroud having a top with four depending sides removably secured to the roof top in a fixed position, the shroud having dimensions permitting it to enclose the jacket and base, together with the unitary air conditioning system thereon, and when so positioned to rest upon the roof top to derive support therefrom with the shroud walls spaced slightly from the jacket walls proximate thereto to provide an air space therebetween, the shroud walls in one end portion thereof being formed with inlet and outlet airopenings through which horizontally-moving air may enter and leave the air conditioning system therewithin, and in its end portion oppositely of the shroud openings the base being formed with openings communicating through vertical ducts with a room below the roof top, one of which ducts permits air to be propelled downwardly into the room and the other to return room air therefrom in response to operation of the air conditioning system.

10. A roof-type base mounting an air conditioning system as specified in claim 9 wherein the shroud encloses a hot air discharge duct extending crosswise above the base with its delivery end terminating in a plane parallel with and adjacent to a side wall of the shroud directly oppositely of the air outlet opening therethrough, and blower means is operable to propel heated air through the duct and outlet opening of the shroud into the outside atmosphere.

11. A rooftype base mounting an air conditioning system as specified in claim 9 wherein the shroud encloses a hot air discharge duct extending crosswise above the base with its delivery end terminating in a plane parallel with a side wall of the shroud directly oppositely of and adjacent to the air outlet opening therethrough, and wherein one jacket wall extending beyond the outlet opening of the shroud is formed thereat with an edge notch to accommodate the proximate portion of the duct adjacent its delivery end.

12. A roof-type base mounting an air conditioning system as specified in claim 9 wherein feet depending from the shroud walls at spaced intervals engage with the roof top lea-ving therebetween raised bottom edges defining elongated openings through which outside air is free to enter into the spaces between confronting walls of the shroud and jacket, and wherein the air spaces are substantially continuous between such confronting walls at one end, both sides and over the top of the jacket to permit air entering thereinto at roof top level from one direction to promote movement of air therewith and egress therefrom at an opposite point at roof level whereby to serve as a cooling medium therefor.

13. A roof-type base mounting an air conditioning system as specified in claim 9 wherein a heat-generating motor-compressor comprised in the system is mounted on the base at one corner portion thereof, and wherein the inlet openings in one end portion of the shroud are located in an end and side wall thereof at the shroud corner proximate to the base corner whereat the motor-compressor is mounted, to admit outside air into the near-by space interiorly of the shroud where the heat-generating motor-compressor is also located.

References Cited UNITED STATES PATENTS 2,447,278 8/ 1948 Roper 6 2-259 2,682,757 7/1954 Borgerd 62-259 2,770,955 11/1956 Lundstrum 62259 WILLIAM J. WYE, Primary Examiner.

US. Cl. X.R.