US2869832A - Apparatus for air conditioning - Google Patents

Apparatus for air conditioning Download PDF

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US2869832A
US2869832A US567699A US56769956A US2869832A US 2869832 A US2869832 A US 2869832A US 567699 A US567699 A US 567699A US 56769956 A US56769956 A US 56769956A US 2869832 A US2869832 A US 2869832A
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unit
convector
air
units
wall
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US567699A
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John W Mcelgin
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JOHN J NESBITT Inc
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JOHN J NESBITT Inc
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F1/00Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station

Description

Jan. 20,1959 J. w. MOELGIN. 2,369,832
APPARATUS FOR AIR CONDITIONING Filed Feb. 24, 1956 5 Sheets-Sheet 1 A i 7' T i go (0 A INVENTOR JOHN MELGIN ATTORNEYS Jan. 20, 1959 J. w. MOELGIN Y 2,869,832
APPARATUS FORHAIR CONDITIONING Filed Feb. 24, 1956 5 Sheets-Sheet 2 \N \NN INVENTOR JOHN M ELGIN J. W. M ELGIN APPARATUS FOR AIR CONDITIONING Jan. 20, 1959 5. Sheets-Sheet 3 Filed Feb. 24, 1956 INVENTOR JOHN MEtGIN B ATTORNEYS a W 20, 1959 J, w, MoELGlN 2,869,832
APPARATUS FOR AIR CONDITIONING Filed'Feb. 24, 1956 5 Sheets-Sheet 4 INVENTOR 1 JOHN MCELGIN Jan. 20, 1959 w MCELGIN APPARATUS FOR AIR CONDITIONING 5 Sheets-Sheet 5 Filed Feb. 24, 1956 INVENTOR JOHN M ELGIN I B! r h l ATTO tut-ab APPARATUS FGR AIR CONDITIONING John W. McEigin, Philadelphia, Pa., assiguor to.Jhn J. ,Nesbitt, 1119., Philadelphia, Pa., a corporation of Pennsylvania' Application February-24, 1956, Serial No. 567,699
2 Claims. (Cl. 257 -2) This invention relates to air conditioningsystem's and control arrangements therefor, and to methods of operation thereof.
In the conditioning of the air in enclosures, such as rooms, a well-known unit is one of .the nature wherein both inside and outside air are blown through. heating units into the enclosure being treated. Control exercised over the supply of heating medium to the heating element, and further control exercised over the proportions in which the inside and outside air are admixed enable the general temperature and air conditions of the enclosure to be regulated relatively. closely.
The heating element in systems of this nature may be arranged for receiving, a supply of refrigerating. medium, if desired, so that the unit can either supply heat to the enclosure, can recirculate air in the enclosure and supply noheat thereto, or can exercise a cooling efiect on the circulated air.
Units of the general nature referred to above and controls thereforare illustrated in my issued Patents No. 2,216,350 of October 1, 1940, No. 2,268,048 of December 30, 1941, No. 2,286,749 of June 16, 1942, and No. 2,290,985 of July 28, 1942. Also, in my co-pending application, Serial. No. 159,009, filed April 29, 1950, now Patent No- 2,696,948, a conditioning unit of the same general nature and arrangement is illustrated, and over which arrangement the instant invention represents an advance. i
The conditioning units according to the above-identified patents and application, and also as disclosed in the pres ent' application, have proved highly satisfactory so far as regulating the temperature and condition of the air in the associated enclosure as regards average conditions throughput. However, in many instances, notably in school classrooms and the like, one, and sometimes two, walls of the enclosure may consist principally of glass. A wall of this nature, especially when itbecom'es relatively long, as in a modern classroom which may -be-upwards'of fifty feet inlength, can. create cold downdrafts immediately adjacent the wall which have a tendency to influence the temperature of'the enclosure along the wall, even though the average temperature of the enclosure is maintained at the proper degree.
- Inasmuch as the air'conditioning'unitsreferred. to are small dimensionally relative to an enclosure for-"which they have; suficient capacity for conditioning: the air, the supply of conditioning air from the'units is necessarily discharged into the enclosure into a relatively: restricted zone. An arrangement employing. one" or even-several of the units is thus'incapable of offsetting the cold drafts from the windows.
These cold drafts can be offset to a certainextent by employing a plurality of the units, but this is impractical because a great deal more conditionin-gcapacity is embodied inv an installation-of this nature than is necessary.
United States PatentC It'has been. attempted to counteract the cold drafts from the windows by placing auxiliaryv convectorsor radiators alongthe wall, or distributingwonvector units d f* Ice along the wall which will supply heat along thebottoms of the windows and create updrafts which will'prevent the cold window drafts from influencing the room tern perature' along the windowed wall.
Heretofore, combination systems employing unit conditioners with blowers and auxiliary convector units without blowers have not operated particularly satisfactorily because of the difficulty of so interlocking'the units that they will always operate in unison.
Specifically, such systems, and which are known as split systems, had a tendency toward inefficient-operation because it sometimes occurred that the convector units would be supplying heat when'the blower unit had gone over into its. cooling'cycle, thus leaving the units operating in opposition, and, therefore, operating in efiiciently. In other cases',.where arrangements were provided for interrupting the supplied heating medium to the convector units at a predetermined temperature in the enclosure, it was found that the convector units actually were only effective during the initial warming up period for the enclosure, and thereafter became idle with all the conditioning being done by the blower unit. This, of course, left the above-mentioned cold window drafts free to' upset conditions in the enclosure along the wall.
In most instances heretofore employing convector units, difficulty was experienced in providing for uniform dissipation of heat along the convector units, thereby leading to a portion of: the cold window drafts being counter acted and other portions not being counteracted.
Having the foregoing in. mind, the primary object of the present invention is to provide an air conditioning arrangement provided with blower type conditioning units and auxiliary convectors, such that the entire enclosure being treated by the system is at a substantially uniform temperature at all times, even along cold walls, and Wherein the system operates eiiiciently under all conditions.
A particular object is the provision of a-combination of a blower type conditioning unit and elongated convectors in which the blower type unit and convectors are prevented from ever operating in. opposition.
A still further object is the provision of a convector unit of the nature described characterized in that the dissipation of heat along the length of the convector unit is substantially uniform.
A still further object is the provision of a controlsystern for integrating the operation of a split type air conditioning system having a main blower type unit and auxiliary convector-units, such that the units are always working in unison and neverin opposition.
Another object is the provision of a method of operating a split. type air conditioning system of the nature referred to.
A-particular object is the provision of a split type air conditioning systemv and a control means therefor which is relatively simple and therefore inexpensive to installand easy to maintain in operating condition times.
These and other objects and advantages will become more apparent upon, reference to the following description taken in connection with the accompanying drawings, in which:
Figure 1 is a view loo-king in elevation at. a conditioning arrangement according to this invention arranged along the windowedwall of an enclosure;
Figure 2 is a plan view looking down on top of the unit of Figure l;
Figure 3 is a view like Figur l but showing the unit with the front covers removed from the blower unit portion and from the convector unit portion;
Figure 4 is a view looking down on. top of the unit of which obtain from the operation of the blower unit and Convector unit and the manner in which the heated air from the convector unit blankets the windows;
Figure 6 is a vertical sectional view indicated by line. 6-6 on Figure 1 and is taken through the convector unit;
Figures 7 and 8 are fragmentary views showing details of construction in connection with the convector unit;
Figure 9 is .a perspective view partly broken away of the-blower unit of the system showing the arrangement therein of the heating coils, blower, filter, inside and outside air inlets, and damper;
Figure 10 is a sectional perspective view showing the convector unit on one side of the blower unit;
Figure 11 is a diagrammatic view showing the arrangement of the blower and convector units together withthe control system for controlling the su lying of heating medium to the units and for controlling the position of the damper that regulates the proportions of inside and outside air delivered by the blower unit;
Figure 12 is a sectional view showing details in connection with the room thermostat that exercises general control over the system;
- Figure 13 is a view similar to Figure 12 but showing the thermostat that is positioned in the air stream from the blower unit of the system and which exercises second ary control over the system, particularly in connection with the motor that regulates the position on the damper of the blower unit;
Figure 14 is a fragmentary perspective view illustrating the manner in which'the convector units can be embodied in a cabinet or bookshelf arrangement; and
Figure 15 is a sectional view indicated by line 15-15- 15 on Figure 14.
. Referring to the drawings somewhat more in detail, and in particular to Figures 1 through 8, there is illustrated an enclosure to be conditioned comprising an outer wall 10 having windows 12 therein. Arranged along the windowed wall 10, in accordance with this invention, is one or more principal blower type conditioning units, as at 14. Also provided in association with the unit or units 14 are the auxiliary convector units 16, extending along the wall 10 beneath the windows 12.
As will be seen in Figures 1 through 5, the principal unit 12 rests on the floor 18 of the enclosure, and the convector units 16 are suspended from the wall of the entczllosure immediately beneath the lower edges ofthe winows.
' The units 14 comprise the grill arrangements, as at 20, along their lower inside walls for the supply thereto of the air from within the enclosure that is to be recirculated through the unit. Each of the units 14 also comprises grill-like openings, as at 22, in the upper surface thereof through which the treated air is discharged.
As will best be seen in Figure 9, each of the units 14 likewise comprises an opening 24 through which air from the outside of the building is drawn into the unit. The openings 20 and 24 are separated by a partition 26, and
immediately above partition 26 is disposed a filter means 28 in the usual manner for filtering the air passing through the unit. A damper 30 is pivotally mounted immediately above the filter and cooperates with partition 26 which extends through the filter to the periphery of the damper so that swinging movements of the damper will control the proportions of inside and outside air drawn into the unit 14.
Immediately above damper 30 is positioned the blowthen issues through the discharge openings 22 at the top of conditioning unit 14.
Turning now to the convector unit arrangement 16, this will be seen in Figures 3, 4, 10 and 11 to comprise interconnected upper and lower reaches of conduit, as at 42 and 44, respectively. The upper reach 44 has a high point at 46 to which a supply conduit 43 is connected. whereas the lower reach 44 has a low point at St? to which the discharge conduit 52 is connected.
The described arrangement assures that steam will be admitted to the convector unit only at the highest point thereof and will move therefrom toward the lowest point of the convector, meanwhile condensing to water, and all of the water condensed in the convector unit will flow therefrom at the lowest point. Furthermore, the portions of the lower reach of the convector unit 16 lying outside of the blower conditioning unit 14 are finned, as indicated at 54. This finned arrangement insures that all of the steam in the lower reach of the convector unit will be condensed into water, because the coolest air engages the fins and also insures a relatively uniform dissipation of heat along the entire lower reach of the convector.
The upper unfinned reach of the convector supplies additional heat to the air and serves also to enhance the speed at which the air passes through the convector.
As will best be seen in Figures 5 and 6, the convector conduit is mounted within an enclosure 56 adapted for being secured against wall 10, as by mounting screws 58. Enclosure 56 has openings 60 in the bottom thereof and grill-like openings 62 in the top thereof. Spaced bracket means 64 support the upper reach 42 of the convector at the proper elevation and are arranged to give the desired fall to the said upper reach, whereas other bracket means, as at 66, similarly support the lower reach 44 of the convector.
For convenience in installing and servicing the convector unit, a cover 56 may advantageously be arranged, as illustrated in Figures 6 through 8, wherein it will be seen that a groove 68 is formed on the back wall of the convector unit for receiving the turned-down edge or tongue 70 extending along the rear edge of the upper wall of the housing or cover 56. The rear edge of the lower wall of the cover or housing is detachably connected as by screw and nut 72 to the forwardly turned lower edge of the back supporting plate of the convector.
Referring now to Figure 11, the blower conditioning unit and the convector unit are shown more or less diagrammatically in association with the system which controls their operation. In Figure 11 the control system comprises a conduit 70 which is supplied with 'fluid at a predetermined pressure from a source not illustrated. Ordinarily, the fluid employed is air, but. it will be understood that the, control system could be operated hydraulically or electrically, or in other manners well-known in the art, if desired.
Conduit leads to a room thermostat, generally indicated at 82, and which comprises a bleed port 84, as is better illustrated in Figure 12. Port 84 is adapted for being variably restricted by bafile 86 that is adjustably connected, as by screw 88, with the movable end of a bimetallic strip 90. Strip 90 'is so arranged that it will move due to increasing temperatures in the room in a direction to restrict bleed port 84, and will move in the opposite direction when the temperature decreases.
Conduit 80 on the downstream side of thermostat 82 is connected with the valve operator 92 associated with control valve 94 in conduit 48 that regulates the supply of heating medium to the convector unit.
Conduit 80 also leads through a restrictor valve 96 to the operator 98 associated with control valve 100 in supply conduit 102 leading to the heating unit 38 of the blower conditioning unit 14.
0n the downstream side of operator 98 conduit 80 is connected: with-the air stream thermostat 104, which is better illustrated in Figure 13. This thermostat also comprises a bleed port 106 adapted for being. variably restricted by baflie 108. Bafiile 108 bears on the end of a rod 110 within hollow sleeve 112 and a spring 114 continuously holds the baffie plate and rod in engagement. The arrangement is such that sleeve 112 will expand when the temperature to whichit is exposed increases, whereas rod 110 is substantially insensitive to temperature changes, whereby the said increasing temperaturebrings about greater restriction of bleed port 106.
Similarly, reduction in the temperature to which the thermostat is exposed will cause contraction of sleeve 112 leading to reduction in the restriction of bleed port 106;
Conduit 80 from its connection with thermostat 104 leads to damper motor 116 connected by means of link age 118 withdamper 30, whereby the position assumed by the damper is determined by the pressure in conduit 80; as brought about by the thermostats82 and .104.
In operation, starting with a coldroom, steam, or other heating medium, is suppliedto the blower unit 14 and thepconvector unit through their open supply valves 9,4 and100. Damper motor 30 at this: time is positioned to introduce the ,minimum amount' of outside air, and the drive motor 120 associated with the blowers in unit 14 is energized.
As the room commences to warm up, thermostats 82 and 104 will respond by moving their respective baffles toward their respective bleed ports, thereby to throttle the discharge of air from conduit 80 and to cause a buildup of pressure therein. When the pressure in conduit 80 upstream of restrictor 96 reaches a value of, say, eight pounds per square inch, the valve 100 associated with heater element 38 of conditioning unit 14 is closed by operator 98. At this time the damper remains in position to admit minimum outside air, and valve 94 for the convector unit remains open.
As the room temperature increases further, the room thermostat gradually closes still further, and when the pressure in conduit 80 reaches about twelve pounds per square inch, valve 94 in supply conduit 48 leading to the convector unit is closed by its operator 92.
At this time the damper still remains in its original position, wherein a minimum of outside air is introduced into unit 14.
A still further increase in room temperature will bring about further restricting of the bleed port of thermostat 104, thereby increasing the pressure to damper motor 116, whereupon the damper motor will actuate the damper to admit more outside air into the enclosure.
From the foregoing, it will be observed that the air conditioning unit according to my invention is so arranged and controlled that the convector unit or units, as the case may be, is operative throughout the time that the main blower unit or units operate to supply heat to the enclosure, and this prevents the condition arising that was referred to previously, where the heating load for the enclosure was carired by the blower unit, with the convector units running idle.
The net result is to provide for more uniform temperatures throughout the enclosure, while the portion of the enclosure adjacent the cold wall is blanketed and insulated from the effects of loss of heat through the wall.
A graphic indication of the manner in which the combination of the convector unit and the blower unit cooperate in warming an enclosure is illustrated in Figure 5. Figure 5 shows, by means of arrows 122, the general path that the air takes that is circulated by the convector unit, whereas the arrows 124 generally indicate the path taken by the air that is blown through the main unit 14. It will be understood that the diagram of Figure 5 is being retained in position on a wall by screws 134. Ar-
ranged immediately in front of the convector is a vertical wall panel 136 terminating above the level of floor 138. Panel 136serves'as a back for a cabinet arrangement including a plurality of shelves 140, the upper of which may besubstantially coplanar with the grilled cover plate 142immediately' above thelconvector, and the lower of which maybe formed downwardly, as indicated at 144 to'the floor andmay comprise apertures 146 for admitting the air that is to be warmed by the convector. The Figures 14 and 15 arrangement presentsthe advantage that theconvector is co'mple'telyconcealed', and also establishes' a' relatively elongated flue for guiding the air to the convector from immediately above the floor and for distributing the air along the convector.
The controls to .be associated with the Figures 14 and convector can be identical with the controls described in connection with the previous modification.
It is to be understood that in either of the convector arrangements illustrated, the results obtain that there is a'uniform discharge of uniformly warmed air along the entire length of the convector whenever there is a supply of said medium to the convector. I have found in carrying out my invention that a supply of heating medium to the convector sufficient to produce an output of four hundred and fifty B. t. u. per foot is adequate to create an effective heat blanket to counteract even severe conditions.
It will be understood that this invention is susceptible to modification in order to adapt it to difierent usages and conditions, and accordingly it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.
I claim:
1. In an air conditioning system for positioning against the wall of a room, the combination of a main heating and ventilating unit having a heat exchange element and a blower, said main unit being positioned against the wall of a room and having both inside and outside air inlets and an air outlet on the top thereof, a damper in said main unit for inversely varying the areas of said air inlets, there being means in the air outlet of said main unit to direct heated air upwardly and outwardly into the room to raise the temperature thereof to a desired level, an elongated auxiliary convector unit longer than said main unit extending laterally from said main unit against the wall of the room and having openings in the top and bottom surfaces thereof, there being means in the openings in the top surface of said convector unit to direct a blanket of heated air vertically upwardly against the wall, a heat exchange element in said convector unit, a common source of a heating medium connected to said heat exchange elements, and a control system comprising a thermostat responsive to the temperature of the room for first shutting off the heating medium to said main unit and then shutting off the heating medium to said convector unit as the room temperature approaches a predetermined level so that the convector unit operates throughout the time that the main unit supplies heat to the room to blanket the wall from loss of heat through the wall, said system also having means comprising a thermostat in the main heating and ventilating unit downstream from said blower and responsive to the heated air discharged thereby and cooperatively associated with said room thermostat for subsequently controlling said damper after the supply of heating medium to the main and convector heat exchange elements has been shut off to admit more outside air to the room as the temperature of the room increases.
2. In an air conditioning 'system for positioning against the wall of a room, the, combination of a main heating and ventilating unit having a heat exchange element and a blower, said main unit being positioned against the wall of a room and having both inside and outside air inlets and an air outlet on the top thereof, a damper in said main unit for inversely varying the areas of said air inlets, there being means in the air outlet of said main unit to direct heated air upwardly and outwardly into the room to raise the temperature thereof to a desired level, an elongated auxiliary convector unit longer than said main unit extending laterally from said main unit against the wall of the room and having openings in the top and bottom surfaces thereof, there being means in the openings in the top surface of said convector unit to direct a blanket of heated air ver tically upwardly against the wall, a heat exchange element in said convector unit, a common source of a heating medium connected to said heat exchange elements,
a fluid pressure actuated valve in each of said connections to shut off individually the flow of heating medium to the main unit and convector unit heat exchange elements, a room thermostat and a fluid pressure control sys tem connecting said room thermostat to each of said valves and said damper to close the main unit valve as the temperature of the room increases to the desired level and then to close said convector unit valve after the main unit valve has closed, and upon further increase of the room temperature so that the convector unit operates throughout the time that the main unit supplies heat to the room to blanket the wall from loss of heat through the wall, anair stream thermostat in said main unit downstream from said blower and responsive to the heated air discharged by said blower, and a conduit connecting said air stream thermostat to said control system on the downstream side of said main unit and convector unit valves to control said damper after the supply of heating medium to said main unit and convector heat ing unit heat exchange elements has been shut ofito admit more outside air to the room as the temperature of the room increases;
ReferencesCited in the file of this patent UNITED .STATES PATENTS McElgin Dec. 25,
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3194304A (en) * 1961-12-20 1965-07-13 Titus Mfg Corp Variable volume terminal unit with reheat
JPS5228261U (en) * 1975-08-20 1977-02-26
US4320870A (en) * 1979-12-12 1982-03-23 Giora Manor Temperature control systems

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1886292A (en) * 1930-02-01 1932-11-01 Modine Mfg Co Radiator
US1922220A (en) * 1931-07-01 1933-08-15 Etta Grant Sprague Heating and ventilating apparatus
US2235500A (en) * 1938-10-03 1941-03-18 Francis A Kitchen Heating and ventilating apparatus
US2298810A (en) * 1938-06-06 1942-10-13 Honeywell Regulator Co Control system
US2327663A (en) * 1940-12-06 1943-08-24 Herman Nelson Corp Heating and ventilating apparatus
US2775432A (en) * 1951-07-23 1956-12-25 John J Nesbitt Inc Apparatus for air conditioning

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1886292A (en) * 1930-02-01 1932-11-01 Modine Mfg Co Radiator
US1922220A (en) * 1931-07-01 1933-08-15 Etta Grant Sprague Heating and ventilating apparatus
US2298810A (en) * 1938-06-06 1942-10-13 Honeywell Regulator Co Control system
US2235500A (en) * 1938-10-03 1941-03-18 Francis A Kitchen Heating and ventilating apparatus
US2327663A (en) * 1940-12-06 1943-08-24 Herman Nelson Corp Heating and ventilating apparatus
US2775432A (en) * 1951-07-23 1956-12-25 John J Nesbitt Inc Apparatus for air conditioning

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3194304A (en) * 1961-12-20 1965-07-13 Titus Mfg Corp Variable volume terminal unit with reheat
JPS5228261U (en) * 1975-08-20 1977-02-26
US4320870A (en) * 1979-12-12 1982-03-23 Giora Manor Temperature control systems

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