US2650075A - Atmospheric condenser for refrigerating systems - Google Patents

Description

25,, 1953 J. M. ANDREWS 2,650,075

FOR REFRIGERATING SYSTEMS ATMOSPHERIC CONDENSER Filed Sept. 6

Fisl

I INVENTOR.

John M.Andrews AI R STREAM 34 Fica.4-

Patented Aug. 25, 1953 ATMOSPHERIC CONDENSER FOR REFRIG- 7 ERATING SYSTEMS John M. Andrews, York, Pa., assignor to York Corporation, York, Pa., a corporation of Delaware Application September 6, 1951, Serial No. 245,325

3 Claims.

The invention relates to air-cooled heat exchangers, specifically condensers such as are used in refrigerating systems. The novelty resides in the means used to deliver water to the fins of small finned air-cooled condensers over which air is rapidly circulated by a fan.

The water may be supplied from any source, but commonly is drip water condensed from the air on the refrigerative evaporator commonly present in air conditioners.

Inexpensive construction, silent operation and uniform distribution of water to all fins are the advantages offered by the invention. Observation of the device in operation shows that the fins are nearly uniformly wetted over the entire extent of the condenser, and yet water droplets are not blown out in the air discharge stream.

An embodiment which has been built and has demonstrated excellent operating characteristics will be described as an example, reference being made to the accompanying drawing, in which:

Figure 1 is a plan view of the distributing trough with the lid removed. A few condenser fins are shown to disclose the spacing.

Figure 2 is a perspective view of the trough with one end plate removed and the lid swung up to an extreme position which it never reaches in operation;

Figure 3 is a vertical section through the condenser and related parts on a. plane parallel with the fins. The lid is shown closed.

Figure 4 is a fragmentary section similar to a portion of Figure 3 but on a larger scale, showing the lid open to about the maximum extent occurring in service.

All statements of direction will be made with reference to Figure 3.

The condenser comprises substantially horizontal parallel tubes H which pass through parallel, vertical plate fins 12. Tubes and fins for usual refrigerants are of copper. The fins are closely spaced, as indicated in Figure 1, and as indicated by legend on Figure 3, air is blown by a fan or other means continuously in a generally horizontal direction from left to right, and through the intervals between fins.

The construction of the condenser is conventional and hence its inlet and discharge connections, and the connections between the tube passes are not shown.

The condenser is mounted above a drip pan including a bottom l3 and'marginal rim M. A depression I5, snail-shell in form, is pressed in the bottom l3 and with the cover plate I6 serves as the housing for a centrifugal pump whose runner comprises radial vanes I! carried by a vertical shaft H3. The vanes may be of metal and rigid, or of somewhat flexible rubber-like material, both types being known.

Plate It has inlet ports through which water from the pan flows into the pump, and carries a bracket l9 supporting the shell 2| which supports bearings for shaft I8 and may house accessory apparatus, not here material. The shaft connection for the pump. Pipe 23 is offset and connected to nipple 24 through which water from the pump enters a trough generally indicated by the numeral 25.

The form and arrangement of trough 25 are the most significant features of the invention.

The trough is approximately semi-circular in cross-section and extends horizontally the full width of the air entrance face of the condenser. It is located close to fins I2 and only slightly below the upper ends of said fins. On that side of the trough which is toward the fins, the trough has a downwardly inclined margin 26, conveniently plane, with a depending lip 21. Along the other side of the trough is an upwardly inclined margin 28 which conveniently is coplanar with margin 26, but not necessarily so. The ends of the trough are closed by plates 29.

Along the edge of margin 28 is a continuous seat 30. The reason for making margins 26 and 28 coplanar is to permit the lid 3| to be constructed as a flat strip with a down-turned rim 32 which coacts with lip 21 to form a downwardly directed nozzle adjustable in width and extending the full length of trough 25 and hence the full width of the condenser.

The lid 3| is hinged by means of a strip of sheet material 33, which may be any durable rubber substitute or flexible synthetic plastic. This strip is cemented or vulcanized to the top face of lid 3| and is clamped between seat 30 and an overlying binder strip 34.

If the rate at which water is supplied to the drip pan varies, and it usually does vary, particularly when it is drip water from the evaporator, the rate of pump delivery will vary similarly and so will the pressure head acting upward on lid 3|. This pressure head is low, and in any event is limited by escape of water between rim 32 and the lip 21 (see Figure 4). Hence lid 3| moves to accommodate itself automatically to the water discharge rate and assures delivery of the discharged water to the fins.

The discharged water is carried by the air stream into the inter-fin spaces. A most remarkably even distribution of water results, with consequent low condenser head pressure. The extensive and active Water-evaporation on the fins and tubes reduces condenser temperature and pressure increasing the efirciency of the condenser and of the entire refrigerative circuit.

Because the water distribution is so even, high evaporative rates are possible without risk of discharging water droplets at the air exit face of the condenser. Discharge ,of liquid water entrained in the cooling air stream is wasteful and the wasted water may create a nuisance. This device allows water to escape with the cooling air only in the vapor phase and does so without eliminators, screens or other recovery expedients.

The downwardly inclined margin 25 and depending lip 21 are important inconjunction with the lid 31 and its rim 32. The forms of these nozzle-forming parts must be suitably coordinated but they can depart from the illustrated embodiment and still perform the function of affording a long pressure-adjusted slot nozzle. The illustrated forms were chosen because they simplify manufacture and are economical of material.

What is claimed is:

1. The combination of a condenser having a plurality of vertical, closely spaced plate-like fins; means for causing a horizontal stream of air to flow through the inter-fin intervals; a trough closed at its ends and having lateral margins at least one of which is inclined downwardly, the trough extending along the upper edge of the entrance face of the condenser with said downwardly inclined margin close to the edges of the fins; a lid adapted to seat against said margins and close the top of said trough, said lid being hinged remotely from the downwardly inclined margin and shaped to conform to the latter; means biasing said lid in the closing direction; and means for continuously delivering water under low pressure to said trough.

2. The combination defined in claim 1 in which the lid and the downwardly inclined margin have flanges which coact to form a downwardly directed nozzle-slot whose width increases as the lid rises.

.3. The combination defined in claim 1 in which the trough margins are in the form of flat coplanar flanges, the downwardly inclined one of which has a pendant lip, the lid is coextensive with the trough and flanges whereby its area exposed to the pressure of the delivered water is materially augmented and the lid is biased closed by its own weight.

JOHN M. ANDREWS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,112,724 Schneider Oct. 6, 1914 1,732,963 Burhorn Oct. 22, 1929 1,955,977 Ross Apr. 24, 1934 2,121,115 Bergdoll June 21, 1938 2,201,834 Mart May 21, 1940 2,259,541 Ballard Oct. 21, 1941 2,289,035 Neeson July 7, 1942 FOREIGN PATENTS Number Country Date 196,960 Great Britain May '7, 1923

Images