US2117410A - Portable air conditioner - Google Patents

Description

y 17, 1938- F. R. ERBACH ET AL.

PORTABLE AIR CONDITIONER I Filed July 1, 1957 2 Sheets-Sheet l f d i A m IWHWHWHIHI wuwn wmomm /o uHQ 1-- 0. 00 0. 37 h 4 2.. 0m n 0. Q. mm m mm, H w O Q Q 0,. MM w omm m Q fi, F iii] ii Qw May 17, F. R ERBACH ET AL PORTABLE AIR CONDITIONER Filed July 1, 1957 2 Sheets-Sheet 2 i l I I I I I F R) i I l l l l i l I I l l I l l I 6206 26 715.- fredfigrpaak, jfldZaffl fl @z/(zrf, g2 g g Mm x mm sme red ay in. rats K Q'DRTABLE am. C(DNDHTHONER d Richard H. Swart, Beloit, (General Refrigeration Coraeration, cit, Win, a. corporation oi Dela- ]Fred R. Erbach an Win, assignors to The invention relates to port ing equipment and has more par to an air conditioner having co and surface cooling features.

The air conditioner of of the combined action to remove heat from which is first washed by said over said cooling coils store is to provi on makes'use f water and cooling coils the air to be conditioned water and then An objectof the do an improved apnlng. air which will have inained by thoroughly washing divided water particles and e mixture over the surface refrigerant medium flowair conditioning equip for operating the ed vertically above packing boxes, beari water level in the cause of seri Another object an air conditioner having a-pump 0 sign and in which water enters at of the cone and is deflected upaches the mouth of the cone, scharged by centrifugal force ntering the fan.

washing of the air as it fan and wate rotative cone de the bottom inlet wardly until it re whereupon it is di across the air stream e arrangement thorough the fanissecured. Y r

ect oi the invention is to provide ling coils each copper tubing and etc evaporator having anrigerant at the outside joined to a suction header at ding to the invention Another obj an improved arrangem consisting of a flat s each forming a compl inlet for the 11 thereof and being the inside of'the coil. Accor have a downward pitch as they D 30- enter oi the coil, thereby per-' rant admitted to the inward toward The arrangement also rethe counter-flow principle 4 The liquid refrigerant is fed f the evaporator coils and ex-' sses toward the gress toward the c mitting the liquid refrige outside coil of the spi the" suction header. suits in accomplishl vin heat exchange.

in at the outside 0 pension takes center, producing the the air as'it passes coils, being discharged thereof, is gradual] fromthe outlet has ral to drain place as it progre well known cooling over the evaporator from the inside ed and the discharged air the lowestjtemperature pos- Theinvention is also. concerned with the profi iimli Application July 11, 193?, Serial No. 151,361 3 611a. (QR. 261-91) able air condition-' ticular reference mbined washing vision of air conditioning equipment as above described, wherein the cooling surfaces can be readily cleaned to remove deposits of dust and dirt, and the like, which might adhere thereto as a result 01 the continual discharge of air over said 5 coils and the spraying of water thereon. In the operation of the air conditioner the water may cause. an encrustatlon over the surface of the cooling coils, which in the present air conditioning equipment are mounted in a tank that can be flooded to submerge the coils in a cleaning solution of the proper, chemical analysis for dissolving the particular type of mineral deposits left on the coils by their contact with the conditioned air and washing water. With these and various other objects in view. the invention may consist of certain novel i'eatures of construction and operation as will be more fully described and particularly pointed out in the specification, drawings and claims appended hereto. v

In the drawings which illustrate an embodiment of the invention and wherein like reference characters are used to designate like parts- Figure 1 is a vertical elevational view showing the internal construction of an air conditioner embodying the featuures of the invention; l

Figure 2 is a top plan view of the air" condi tioner of Figure-l with the cover plate for-the tank, and motor removedyand Figure 3 is a. sectional view showing in detail the internal construction 'ofthe expansion valve for uniformly feeding liquid refrigerant to a plurality of cooling coils.

Referring to the drawings, the operative parts of the present air conditioner are shown as supported upon a table having a top l0 substantially rectangular in plane and which is suported on any suitable foundation by means of the uprights ll having circular foot rests 12. The top plate 40 l0"comprises the bottomof the tank which is formed by the cylindrical side wall I welded to said top plate so as to make a liquid-tight connection therewith.- The top member of the tank through openings formed in the cover and re-\ ceive screws l8, thereby releasably securing the cover in place. Said cover has formed integral therewith upwardly extending lugs 20 which form supports for plate member 2|, the same being releasably secured thereto by the threaded screws 22. The rubber inserts 23 are interposed therebetween in order to cushion the vibrations of the motor 24 supported by said plate member. The rotor shaft 25 of said motor extends centrally through opening 26 in the cover l5 formed by the downwardly curved walls 21. Attached to the lower end of said rotor shaft by the connecting webs 28 is a pump tube formed by the inverted cone 30. Said pump tube carries a centrifugal fan designated generally in Figure 1 by numeral 3| and which consists of a base member 32 supporting a plurality of radial plates or blades 33.

Located within the tank l4 and positioned concentric with the centrifugal fan are a plurality of cooling coils 36, each in the form of a flat spiral disposed so as to give each spiral a downward pitch as the same progresses from the outer coil thereof to the inner coil. Each spiral has connection at its inner end to a suction header 35 which extends through the base III of the tank and has connection at 36 with the suction line 31 of the refrigerating system which returns the refrigerant gas to the compressor. The spaced vertical rods 38 maintain the spiral coils in proper superposed relation. Three sets of these rods are used, each set being retained in spaced relation by the top member 40 which is held against the rods by the screws il having threaded connection with cover 15.

The outer end of each spiral coil is supported by member 42 which maintains said end of the coil in proper spaced relation. Liquid refrigerant is supplied to each coil by the expansion valve, designated in its entirety by numeral 44, said valve being suitably supported in the upper part of the tank immediately below the cover i 5 and to the side thereof substantially directly over the member 42. From the outlet fitting 45 of the valve a plurality of tubes 46 lead to the spiral coils, each coil having connection with a tube whereby liquid refrigerant is delivered thereto.

As more particularly shown in Figure 3, the expansion valve 44 may be a conventional thermostatic expansion valve having an inlet tube 48 connecting with the inlet fitting 49 for supplying liquid refrigerant to said valve. The conical valve member 50 formed on the end of rod 5| controls the flow of liquid refrigerant to the outlet fitting 45'above described and which connects with the capillarytube's 46, each tube leading to the inlet end of a cooling coil 34. The expansion valve is also provided with a pressure responsive diaphragm 52 which has connection with the wave member 50 through rod 5|. Said diaphragm is biased toward the right, that is, in a valve closing. direction, by the pressure of the evaporated refrigerant gas within the suction header 35, which pressure is communicated from said header through the tube 53 to the space on the underside of the diaphragm. The diaphragm is also biased toward the left, or in a valve opening direction, by the pressure produced by the thermostatic bulb 54, which pressure is communicated through tube 55 to the space on the upper side of the diaphragm. It will be observed that the thermostatic bulb 54 is clamped to the suction header 35 and thus the average discharge temperature of the refrigerant gas leaving the plurality of cooling coils 34 influences the thermostatic fluid in said bulb to produce correspending variations in pressure on the upper side of the diaphragm, The pressure produced by the thermostatic bulb is a function of the average temperature of the returning refr g rant 5&5.-

Inasmuch as the pressure within the suction header 35 is a function of the saturation temperature of the refrigerant gas, the difference in pres sure imposed on the diaphragm will be a function of the superheat of the refrigerant leaving the series of cooling coils. The coil spring 56 yieldingly forces the valve member 50 in a closing direction in opposition to the pressure difference on the diaphragm which tends to open the valve.

The space between the cover i5 and the plate member 2! forms the air inlet for the centrifugal fan, air being drawn through said space and through the central opening 26 in said cover and being delivered thereby to the fan 3|. The duct 58, substantially rectangular in cross section, comprises the air outlet for said tank, said duct having a tangential connection therewith, as will be clearly understood by reference to Figure 2. Water is supplied to said tank by the water pipe 59 which passes through the side wall of the duct 58 so as to discharge within said duct. The said discharge end of the pipe is secured to the wall by nuts 60. Joined to the water main 59 is a valved connection 6! having handle 62 and provided with tube 63 connecting with a magnetic valve 64 suitably located within the tank. The oulet end 65 from said valve, as shown in Figure 2, terminates over the spiral cooling coils 34. In

an air conditioner of this type it is advisable to supply a small amount of fresh water to the tank periodically to thereby prevent the accumulation of foul odors in the water tank. The magnetic valve which may be arranged to supply water when the conditioner is running would meet the above requirements. For draining said tank it is only. necessary to open the valve 61 located in the water drain 68 which has connection with the bottom it! of the tank.

The cooling coils of the present air conditioner can be submerged by substantially filling the tank with water and for this reason the present tank is constructed so that the air inlet and the air outlet will be above the water level in the tank during the operation of submerging the coils for cleaning purposes. The flood level of the water is determined by the overflow connection 69 joined by pipe HI to connection II. Connection .H is provided with a valve 12 and by means of the cooling coils are located below the normallevel of the water. Thus the coils are submerged during operation of the air conditioner and their effect is to cool the water in the tank which thereby materially increasesthe emciency of the air conditioner.

In operation of the air conditioner above described the pump 30 will dip into the water in the bottom of the tank since the normal water level determined by outlet II will be, as shown in Figure 1, slightly above the lower end of said pipe tube. When the motor 24 is started, causing rotation of the fan, water is caused to flow up the pump tube 3| and to be discharged radially in a finespray from the upper end of said pump tube. Accordingly, fine water sprays are directed across the path of the air being delivered to the fan. The pumping action of the inverted cone 30 is dependent on skin friction and the centrifugal force of the water on the interior wall of the invertd cone. Water escapes from the end of said pum'p tube in a substantially horizontal spray and moisture, together with air, is accordingly delivered to the blades of the fan. -In this manner 76 the air prior to being delivered to the cooling coils 34 is washed by a water spray in the form of finely divided particles. The discharge from the fan is directed into contact with the series of superposed cooling coils 34, each coil comprising an independent evaporator having a capillary tube 46 delivering liquid refrigerant thereto and having connection at its opposite end with the suction header 35. The washing of the air with water having a relatively low temperature considerably reduces the temperature of the air, which, however, -is further cooled due to surface contact with the cooling coils 34. The coils remove considerable moisture irom the air which drips from said coils and in this manner is returned to the reservoir in the bottom of the tank. The method of conditioning the air by first water washing the air and subsequently passing the washed air over cooling coils is very effective and has the further advantage of economy in operation.

The liquid refrigerant delivered by the inlet 48 to the expansion valve is distributed uniformly by the outlet fitting 45 to the plurality of capillary tubes 46 which have connection respectively with a cooling coil. By controlling the fiow of refrigerant in accordance with the superheat the cooling coils are supplied with a quantity of refrigerant that can be completely evaporated thereby.

Another feature of the present air conditioner resides in the downward pitch of the spiralcoils as they progress toward the suction header 35. This facilitates the flow of the liquid refrigerant toward the suction header.

An air conditioner of the above type presents a serious problem in that the surfaces of the cooling coils become coated with deposits left by the water continually brought in contact therewith. In the present structure the tank can be flooded to submerge the coils in a cleaning solution of the proper chemical analysis to dissolve the particular type of mineral deposit left in the coils. This flooding is made possible by locating the air inlet opening and air discharge opening above the upper level of the coils. For the cleaning operation the motor 26 is stopped and the valve 12 is closed. Water from the water main 58 is then admitted to the tank by opening the valve controlled by the handle 13. Water will fill the tank to a level determined by the overflow connection 69. The proper quantity of cleaning solution is added to the water in the tank after the coils are submerged. During the cleaning operation the solution may be stirred occasionally. At the end of the cleaning operation the drain 68 is opened to completely drain the solution from the tank.

During operation of the present air conditioner it is possible to add chemicals to the water in the tank to assist in the purification of the air or to add chemicals to impart a pleasing and characteristic odor to the conditioned air.

The invention is not to be limited to or by details of construction of the particular embodiment thereof illustrated by the drawings, as various other forms of the device will of course be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims.

What is claimed is:

1. Apparatus for washing and cooling air, in combination, a tank providing a reservoir for water, a centrifugal fan mounted for rotation on a vertical axis and located in the upper part of said tank, means rotating with the fan for drawing water from said reservoir and discharging the same radially from the center of said fan in the form of finely divided sprays, whereby air entering the fan is washed by contact with said water sprays, and a plurality of cooling coils each in the form of a substantially fiat spiral encircling said fan and located in the path of the air discharged thereby, an expansion valve for uniformly delivering liquid refrigerant to said coils, and means maintaining said reservoir at a constant water level during operation.

2. Apparatus for washing and cooling air, in combination, a tank providing a reservoir for water, a centrifugal fan mounted for rotation on a vertical axis and located in the upper part of said tank, a pump tube depending from the center of said fan and dipping into said reservoir, said pump tube drawing water therefrom and discharging the same radially from the center of said fan in the form of finely divided sprays, whereby air entering said fan is washed by said water sprays, a plurality of superposed cooling coils encircling said fan and located in the path of the air discharged thereby, an expansion valve for uniformly delivering liquid refrigerant to said coils, and an outlet for the washed and cooled air located above the level of said cooling coils, whereby said tank may be substantially filled with water to submerge the cooling coils in order to clean said coils.

3. In an air conditioner, the combination with a tank forming a reservoir for water, of a plurality of cooling coils supported within said tank, a motor operated fan positioned centrally of said coils and operating to discharge a water and air mixture over said coils, an air supply inlet located above the fan, an air discharge outlet located above the level of the cooling coils whereby said tank may be substantially filled with water to submerge said cooling coils for the purpose of cleaning the same, and means for completely draining said tank.

4. In an air conditioner, the combination with a tank forming a reservoir for water, of a plurality of superposed cooling coils each in the form of a substantially flat spiral supported within said tank, a motor operated fan positioned centrally of said coils and operating to discharge a water and air mixture over said coils, an air supply inlet positioned above said fan, an air discharge outlet located above the level of said cooling coils whereby said tank may be substantially filled with water for submerging said cooling coils, an overfiowconnection for said tank determining'the level of the water when said coils are submerged, and means for completely draining said tank.

5. Apparatus for washing and cooling air, in combination, a tank providing a reservoir for water, a centrifugal fan mounted for rotation on a vertical axis and located in the upper part of said tank, means rotating with the fan for drawing water from said reservoir and discharging the same radially in the form of finely divided sprays from the center of said fan and in a direction;.substantially horizontal, whereby said water sprays traverse the air streams entering said fan to wash the air, and a plurality of cooling coils within said tank, said coils comprising substantially fiat spirals encircling the fan and located in the path of the air discharged thereby.

6. Apparatus for washing and cooling air, in combination, a tank providing a reservoir for water, a centrifugal fan mounted for rotation on a vertical axis and located in the upper part of said tank, means rotating with the fan for drawing water from said reservoir and discharging the same radially in the form of finely divided sprays from the center of said fan and in a direction substantially horizontal, whereby said water sprays traverse the air streams entering said fan to wash the'air, a plurality of cooling coils within said tank, said coils comprising substantially flat spirals each having a downward pitch as it progresses toward its inner end and having connection at said end with a suction header, and an expansion valve delivering liquid refrigerant to the outer end of each of said cooling coils.

7. Apparatus for washing and cooling air, in combination, a tank providing a reservoir for water, a centrifugal fan mounted for rotation on a vertical axis and located in the upper part of said tank, means rotating with the fan for drawing water from said reservoir and discharging the same radially in the form of finely divided sprays from the center of said fan and in a direction substantially horizontal, whereby said water sprays traverse the air streams entering said fan to wash the air, and a plurality of cooling coils within said tank, said coils comprising substantially flat spirals encircling the fan and located in the path of the air discharged thereby, and certain of said coils being submerged by the water in the tank, thereby cooling the water and materially increasing the efiiciency of the apparatus.

' FRED R. ERBACH.

RICHARD H. SWART.

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