US2859946A

US2859946A - Heat exchange device

Info

Publication number: US2859946A
Application number: US484952A
Authority: US
Inventors: John R Boyle; Jr John R Boyle
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-01-31
Filing date: 1955-01-31
Publication date: 1958-11-11
Anticipated expiration: 1975-11-11

Description

J. R. BOYLE ETAL 2,859,946 HEAT EXCHANGE DEVICE Nov. 11, 1958 2 Sheets-Sheet 1 Filed Jan. 51, 1955 I s m m m m 9 6, qyle, a ao kawm 2 Sheets-Sheet 2 INVENTORS I Jab/Z550 Boyle, J7; m Y

Nov. 11, 1958. J. R. BOYLE ET AL HEAT EXCHANGE DEVICE Filed Jan. 51, 1955 gw liilxlilw .UHH IM IH IHUJ BY Jo/zrzfi W/WAM United States Patent '0 HEAT EXCHANGE DEVICE John R. Boyle and JohnR. Boyle, Jn, Chicago, Ill.

Application January 31,- 1955, Serial No.-. l84,952

'11 Claims. (Cl. 257-37) The,; present invention relates to a heat 1 exchange device, and more particularly to an evaporativecondenser type of heatexchange device.

More specifically, the-invention airns'to provide an improved heat. exchange, device; comprising a vertically 'disposed helical cooling coil structure disposedabove a water tank, and; utilizing a motor driven rotary spinner extending; downwardly; inside ;the' coolingqcoilv structure and provided with centrifugal water lifting means and .;centrifugal water spraying. means to lift thevwater, from the. tankqand to ,spray ;it outwardly against the ,coil structure.

Oneof theobjects; of-the invention is to provide an improvedcoil structure and'an'improved method of making-.ithe-same. -flhis, improved coil structure comprises -concentrically disposed-innerandouter helical coils which are physically held; together in fixed concentric spacing ;-by.lo ng narrow finplates which are Pl ced in;intervening -relation; between the inner and-outer coils. plates, are arranged substantially radially. of .the inner. and

These fin -outer., coils,, andare spaced close together to providenas .large anareaof heat-radiating surface as possible. .Ea'ch fin plate hasspaced notches along its-inner edge that engage over. the;convolutions of theinner coil, andhas spaced notches along its outer edge that similarly engage over the convolutions of the outer; coil. Thus, the inner .and'outer, coils have; direct heat radiating contact -;with the multiplicity offins, whereby thesefins 'aiford a very large area of -metallic theat radiating surface, in addition .to; the surface areasoftthe .coils themselves.

rAnotlicr object of-,. the ;invention isto provide .an-improved construction of rotary spinner which is disposed force component to the water forJifting .it from the tank. Thelower portions. of the spinner blades: have pup-shaped lips formed along their outwardly diverging edges for .centrifugally lifting water-from the tank below the ,c,oil...$tructure. In.. the preferred construction. of

-beprojected, the-bend--ofthefiange is diminished to a substantially tangentially shaped lip, which is unable to 'hold the column of water traveling upwardly in the cupshaped lip,-and hence the water is projected centrifugally ,from1this-upper portion-of the spinner.

This substan- "ice 2 tially tangential lip is. preferably crimped. :or.iserrated along its edge to. give abroad, finelyidividedspray lfrom the upper portion of the spinner against the upperap'or- .tionof the coil: and fin assembly,'the' water thenfcascadtingqdown over the .lower portionzlof..-the.acoil;andtifin assembly.

Another object, of theinvention is .to-lproyide the motor driven spinner assemblyqwith anair circulating fan, and witha combined hydraulic. balancing-and water eliminating device. The air circulating fanismounted -on the 'spinner'shaft above-the coil anda-fin assembly, and produces a a forceddraftwof. air flowing through.=.-'the coil and fin assembly. The combined 'hydrauliobala'ncing and water eliminating device is also-mountedyon the 1 spinner shaft ab0vethecoil: andfin assembly, and'functions to catch and trap much of the excess'water vapor .-,whi chts-being. carried upwardly by :the -.foreed-.,draft :of

.-,annulus for balancing the spinner andfan assembly against dynamic unbalance.

air induced by the fan. A part of this accumulation .of water is retained in an internal annular. lip formedtin the device, where this water creates-a hydraulic balancing Other objects, features and advantages of the invention will appear from the following detail descriptionof one preferred embodiment thereof. :In: the: accompanying drawings illustrating. such embodiment:

Figure lis a vertical axial sectional .view through our improved;heat-exchanging device;

FigureZ is a transverse sectional Viewtakenonethe plane of the line 2.2 of Figure 1;

Figures-3 and 4 are side andendpviews"showingthe stepof windinglthe inner coilon a mandrel;

. over the outer edges of the fins;

r-Figures 8,-9 and 10 are transverse sectionalv vie'wsuof the-rotary spinner, taken on the planes-ofsthe l-inesn8-:;8,

Figure 11 ,is a fragmentary edge viewof. the, rotary spinnenshowing edgeportions corresponding to Figures 8,

9 and 10.

The 3 upper portion" of the; device is assembled within asheet metal'housing 16, Which'has a-lower-..end-.-17::of

circular cross-section for, attaching to the.:.ou'ter is'ide'aof the coil-and-fin assembly.- The upperportionzof: the housing may be of-circular, cross-section,-or=of5 oblong cross-section as shown: in-Figure-l. ysupporteddnzthe upper part of the housing ,16by;a mounting yoke 18;:is a vertically disposed electric motor 20. The downwardly extending shaft 21 of this motor -is connectedthrough a flexible coupling 22 to a lower shaft-24 .onwhich-are mounted the air circulating fan 25,.thecombined'hydraulic balancer and water eliminator 26, and- .the rotary spinner 27. The lower end of the -shaft-.24,seats;in a guide bearing 'ZSsecuredto the bottomiwall ofqaqwater tank 30 supported at the lowerend -of the-device.

Surrounding the rotary spinner 27' isrthe coil and'fin assembly 32 comprising the innertubular.,coil:34,,the outer tubular coil 36, and the circularly arrangedgroup of intervening fin plates 38 disposed between vtheg-inner and outer coils. The coil and fin assembly 32 has suitable attachment intermediate its ends tothe circular constricted lower end 17 of the housing .16, with the lower end of the assembly extending downinto the water tank 30 to a point just above the normal water level-in the tank. The fluid to be cooled is circulated through the inner and outer

tubular coils

34 and 36, and the rotary spinner 27 is adapted to lift water fromthe ta'nkf30, and

coil and fin assembly 32, Figures 3 and 4 show the initial operation of winding the inner coil 34 around a rotating mandrel 40. The coil 34 is of a ductile material capable of being wound in this manner about the rotating mandrel 40. After the coil has been thus wound about the mandrel, the sheet metal fins 38 are pressed into position over the coil. One of the fins is shown in side elevation in Figure 5, from which it will be seen that each .fin has semi-circular notches 34 in one edge for engaging over the turns of the inner coil 34, and has semi-circular notches 36 in its opposite edge for receiving the turns of the outer coil. The notches 34' are of such dimension that they have a tight pressed fit over the convolutions of the inner coil 34. As shown in Figure 6, successive fins 38 are pressed over the inner coil in uniformly spaced radially extending relation. The successive fins have their notches 34 spaced successive distances along their lengths corresponding to the different linear positions of the convolutions of the inner coil, the same also being true of the .outer notches 36. Following this mounting of the fins on the inner coil, the outer coil 36 is wound around the radially projecting edges of the fins, with the successiveturns of the outer coil fitting in the notches 36 in the outer edges of the fins, this latter operation being shown in Figure 7. The outer coil 36 is also of ductile metal capable of being wound around the fins in this manner, the winding thereof being preferably performed while the assembly is still on the mandrel 40. After removal of the coil and fin assembly from the mandrel, the upper ends of the inner and outer coils are connected to an inlet chamber 41 and the lower ends are connected to a liquid receiver 42.

Referring now to the rotary spinner 27, this comprises a long metallic plate of tapering or wedge-shaped outline. Extending centrally of said plate from end to end is a half-round or U-shaped indentation 46 which is secured over the spinner shaft 24. Those portions of the tapering plate which extend outwardly from the shaft 24 constitute diametrically opposite spinner blades or

vanes

27a and 27b. Extending upwardly along the lower edge of each spinner blade is a water lifting channel 48 formed by curving the edge of the blade rearwardly into a U-shaped section, as shown in Figure 10. Each water lifting channel 48 is located on the trailing side of its respective vane; i. e. considering the vanes rotating in a clockwise direction, then these water lifting channels 48 are shaped to project counter-clockwise from the edges of their respective vanes. At the lower end of each Water lifting channel 48 is formed a water scoop 49, consisting of a tongue or lip of metal curved to extend horizontally from the lower end of the channel 48. Each water scoop faces in a leading direction with respect to the direction of rotation of the spinner; i. e. for a clockwise direction of rotation of the spinner each water scoop faces in a clockwise direction. The lower end of the spinner is submerged below the water level in the tank 30, and hence the water scoops 49 start the upward flow of water through the water lifting channels 48 on the trailing sides of the

vanes

27a and 27b. Because of the outwardly diverging angle of the water lifting channels 48, the flow of water continues up to the upper ends of the channels under the action of centrifugal force. Beginning at a point just above the constricted portion 17 of the housing, the lip of metal forming the channel 48 is bent in a trailing direction and is formed with a corrugated or serrated edge to form a water spraying lip 52 extending from the water lifting channel 48 to the top of the spinner. This Water spraying lip 52 may have its angle of discharge increase progressively toward the top of the spinner; i. e. the angle subtended between the back side of the vane and the lip 52 may increase toward the top of the spinner. This water spraying lip 52 results in the water being projected from the spinner in a broad finely divided spray over the top half of the coil and fin assembly 32. The excess water cascading down over the coils and fins aids in the cooling of the lower portion of the coil and fin assembly. Attention is directed to the fact that the air is driven off the leading edge of each vane 27:: and 27b, and that the water projected from the spraying lip 52 leaves from the trailing edge of each vane. Hence, the water being sprayed is under a slightly negative pressure, which augments break-up of the water particles and evaporation.

Referring now to the combined air deflector, water eliminator and hydraulic balancer, indicated at 26, this device comprises a hollow cone provided with a hub portion 26a which is mounted on the shaft 24. The lower edge of the cone has an inturned flange 26b which forms an annular water collecting trough 26c concentric with the axis of rotation of the shaft 24. The cone is located sufliciently close to the top of the coil and fin assembly 52 tofunction as an air deflector for deflecting outwardly the air passing up through the center of the coil and fin assembly 32. The fan 25 located above the cone 26 acts to draw a rising column of air upwardly through the coil and fin assembly 32, and the cone 26 functions to deflect the central portion of this rising column of air outwardly from the center of the coil and fin assembly for passage around the edge of the cone. The cone 26 performs its water eliminating functionby trapping water particles which are carried upwardly in the central portion of the rising column of air passing upwardly through the coil and fin assembly 32. When the air is deflected outwardly around the periphery of the cone, a substantial proportion of the heavier water particles will continue their upward travel into the cone, from whence the collected water will be spun centrifugally down into the water collecting trough 26c. The annulus of water held centrifugally in this trough 26c functions as a dynamic balancing medium for dynami cally balancing the rotary spinner 27. The fan 25 operates in a circular opening 55 formed in a partition Wall 56 mounted transversely of the housing 16. The air flow through the device is indicated in Figure l by the wavy arrows a, and the water projection from the upper portion of the spinner 27 is indicated by the dash-dot lines w. In our copending application, Serial No. 484,172, filed January 26, 1955, now U. S. Patent No. 2,773,676, issued December 11, 1956, we have illustrated the present heat exchange device employed as an evaporative condens er in a self-contained heating, cooling and ventilating system for house trailers, small homes and the like. In such situation, the apparatus is enclosed in an outer duct or housing which encloses the housing 16 and water tank 30, leaving space for the admission of air up along the sides of the water tank 30.

Because of the very large amount of surface area of the coil and fin assembly 32, afforded by the multiplicity of fins 38, it is possible to operate the unit dry with a high degree of efliciency, particularly if operating in localities where water is scarce. Thus, the condenser can be of dual operating type, functioning either as a sprayed evaporative condenser or as a dry condenser.

Our invention also contemplates modified methods of making the coil and fin assembly 32. For example, the inner and

outer coils

34 and 36 may be separately formed by the use of suitable tube bending or tube coiling apparatus and may be thereafter assembled one within the other. Following this, the fins 38 having the notches 34 and 36' formed therein may be introduced fiatwise into the space between the coils at one end ,of the coil assembly, each fin being passed up to the proper longitudinal position. between the coils and being then turned 5 edgewise to-lie radially of the coils, with its notches 34 embracing the convolutions of the inner coil 34;=and-with :illS notches .36' embracing the convolutions of-the outer .coil 36.

'While, we have illustrated and described what. we rega'rd to be the preferred embodiment. of the invention, nevertheless it will be understood that such is merely exemplary and that numerous modifications and rearrangements may be made therein without departing from the essence of the invention.

We claim:

1. In a heat exchange device, the combination of a cooling coil, a water tank below said coil, and a motor driven spinner operative to lift water from said tank and to spray it against said coil, said motor driven spinner comprising a plurality of rotating vanes having their lower ends immersed in the water in said tank, each of said vanes having an upwardly and outwardly sloping Water lifting trough operative to lift water centrifugally from said tank for spraying it against said coil.

2. In a heat exchange device, the combination of a cooling coil, a water tank below said coil, and a motor driven spinner operative to lift water from said tank and to spray it against said coil, said motor driven spinner comprising a plurality of rotating vanes having their lower ends immersed in the water in said tank, each of said vanes having a water scoop at its lower end and an upwardly and outwardly sloping water lifting trough operative to lift water from said tank for spraying it against said coil.

3. In a heat exchange device, the combination of a cooling coil, a water tank below said coil, and a motor driven spinner operative to lift water from said tank and to spray it against said coil, said motor driven spinner comprising a plurality of rotating vanes having their lower ends immersed in the water in said tank, each of said vanes having an upwardly and outwardly sloping water lifting trough operative to lift water centrifugally from said tank, and including a discharge lip portion at the upper portion of each Vane for projecting the water against said coil.

4. In a heat exchange device, the combination of a cooling coil, a water tank below said coil, and a motor driven spinner operative to lift water from said tank and to spray it against said coil, said motor driven spinner comprising a plurality of rotating vanes having their lower ends immersed in the water in said tank, each of said vanes comprising a water scoop at its lower end, an upwardly and outwardly sloping water lifting trough operative to lift water centrifugally from said scoop, and a serrated lip portion at the upper end of each vane for projecting the water against said coil in spray form.

5. In a heat exchange device, the combination of a coil and fin assembly comprising an inner coil, an outer coil and a plurality of fins interposed between said coils, a water tank below said coil and fin assembly, and a motor driven spinner disposed Within said inner coil operative to lift water from said tank and to spray it against said coil and fin assembly, said spinner comprising a plurality of rotating vanes having their lower ends immersed in the water in said tank, each of said vanes having-an upwardly and outwardly sloping water lifting trough operative to lift water centrifugally from said tank for spraying it against said coil and fin assembly.

6. In a heat exchange device, the combination of a coil and fin assembly comprising vertically disposed inner and outer coils and fins interposed substantially radially between said coils, a water tank below said coil and fin assembly, and a motor driven spinner disposed vertically Within said inner coil and operative to lift Water from said tank and to spray it against said coil and fin assembly, said spinner comprising a plurality of rotating vanes having their lower ends immersed in the water in said tank, each of said vanes having an upwardly and 6 outwardly sloping water, lifting, trough ,operative, to ,lift water centrifugally from said t ank,-and, each vane-jueluding a discharge lip portion adjacent to its upper end for projecting-the wateragainst saidhcoil and fin assembly.

7.' In a heat exchange device, the combination of a coil and fin assembly. comprisingsvertically disposed inner and outer I spaced "helical coils: and a: plurality of sheet metal fins interposed between and extending lengthwise of said coils in substantially radial planes, said fins having notches in their inner and outer edges embracing the convolutions of said inner and outer coils, a water tank bel w said coil and fin assembly, and a motor driven spinner disposed concentrically within said inner coil and operative to lift Water from said tank and to spray it against said coil and fin assembly, said motor driven spinner comprising a plurality of rotating vanes having their lower ends immersed in the water in said tank, each of said vanes having a water scoop at its lower end and having an upwardly and outwardly sloping water lifting trough operative to lift water from said tank for spraying it against said coil and fin assembly.

8. In a heat exchange device, the combination of a cooling coil, a liquid tank below said coil, and a motor driven spinner operative to lift liquid from said tank and to spray it against said coil, said spinner comprising a plurality of rotating vanes having their ends immersed in the liquid in said tank, upwardly and outwardly sloping water lifting troughs on the lower portions of said vanes from lifting liquid centrifugally from said tank, and discharge lips on the upper portions of said vanes for discharging the liquid against said coil, said discharge lips being disposed on the trailing edges of said vanes so that the liquid discharged therefrom is under a negative pressure.

9. In a heat exchange device, the combination of a cooling coil, a liquid tank below said coil, and a motor driven spinner operative to lift liquid from said tank and to spray it against said coil, said spinner comprising a plurality of rotating vanes having their lower ends immersed in the liquid in said tank, a liquidscoop at the lower end of each vane facing in a leading direction with respect to the direction of rotation of said vanes, an upwardly and outwardly sloping liquid lifting trough on the trailing side of the lower portion of each vane for receiving liquid from said scoop and for lifting liquid contrifugally from said tank, and a discharge lip on the trailing edge of the upper portion of each vane for discharging the liquid against said coil.

10. In a heat exchange device, the combination of a cooling coil, a water tank below said coil, a motor driven shaft extending downwardly through said cooling coil into said tank, a spinner on said shaft comprising vanes operative to lift the water centrifugally from said tank and to spray it on said coil, and a combined water eliminating and dynamic balancing device on said shaft above said spinner, said device comprising an inverted bowl rotating with said shaft and adapted to catch upwardly moving water particles, said bowl including an annular internal lip adapted to hold a dynamically balancing ring of water.

11. In a heat exchange device, the combination of a cooling coil, a water tank below said coil, a motor driven shaft extending downwardly through said cooling coil into said tank, a fan on the upper portion of said shaft for inducing an upward flow of air through said coil, a spinner in the lower portion of said shaft comprising vanes operative to lift the water centrifugally from said tank and to spray it on said coil, and a combined air baffle and hydraulic balancing device on said shaft between the upper end of said coil and said fan, said device comprising an air deflecting member operative to deflect the upward flow of air outwardly through the upper portion of said coil, and including a flange adapted to hold a dynamically balancing ring of Water.

References Cited in the file of this patent UNITED STATES PATENTS 8 Erbach May 17, 1938 Franco-Ferreira Aug.. 20, 1940 Price Feb. 25, 1941 Stikeleather Dec. 23, 1941 Bockmeyer May 23, 1950 Dempsey June 17, 1952