US 3323587 A
Description (OCR text may contain errors)
June 6, 1967 M. A. LOWELL ROLLED PLATE TYPE COOLER 5 Sheets-Sheet. 1
` Filed Aug. 19, 1965 TIG. 2
INVENTOR MAHLON A. LOWELL ATTORNEYS June 6, 1967 M` A. LOWELL ROLLED PLATE TYPE COOLER Filed Aug. 19, 1965 3 Sheets-Sheet. 2
IN VENTOR MAH LON A. LOWELL Bm/ @am/m ATTORNEYS June 6, 1967 M. A. LOWELL ROLLED PLATE TYPE COOLER 3 Sheets-Sheet 3 Filed Aug. 19, 1965 m L E W O L A. N. O L H A M @MQWJ ATTORNEYS United States Patent O 3,323,587 ROLLED PLATE TYPE CLER Maillon A. Lowell, Jackson, Mich., assigner to Acme industries, Inc., Jackson, Mich., a corporation of Delaware Filed Aug. 19, 1965, Ser. No. 480,892 4 Claims. (Cl. 16S-166) The invention pertains to heat exchangers, and particu larly relates to a heat exchanger of the rolled plate or spiral plate type wherein the paths of movement of the heat transfer medium are of a spiral nature and separated by a heat transfer plate.
One of the basic purposes of heat exchangers is to provide a maximum area for heat transfer from one heatconveying medium to another in a minimum of space. The invention pertains to a heat exchanger particularly adapted, though not limited, to fluid heat exchange circuits such as used in refrigeration devices which fulfills this basic object. The heat exchanger of the invention is particularly adaptable as a refrigeration cooler wherein water is being chilled by a refrigerant.
A high efiiciency heat exchanger is produced by forming a conduit from a pair of spaced sheet elements having high heat transfer characteristics. The sheet elements are preferably closely spaced whereby a high ratio of area contact with the fluid contained therein relative to the volume of uid is produced. Although this type of heat exchanger has a high eiciency factor, it is not practical in most applications due to its bulk, inconvenience for handling, and susceptibility to damage.
The invention is directed to a heat exchanger which utilizes the advantages of plate-type heat exchangers whereby a high contact area to fluid volume ratio can be maintained, yet the heat exchanger is of a concise configuration, economical to manufacture, and not unduly susceptible to damage.
It is, therefore, an object of the invention to provide a plate-type heat exchanger, and a method for forming the same, which may be readily manufactured, is of a concise configuration, and is of an economical construction, while providing high eficiency heat-exchanging characteristics.
Another object of the invention is to provide a methody for forming a rolled-type plate heat exchanger wherein a plurality of adjacent ow paths are defined and are maintained in unform relationship throughout the heat exchanger.
Another `object of the invention is to provide a rolledtype heat exchanger and method of forming the same wherein a minimum of tooling and fixtures are required to manufacture the exchanger and wherein economical and commercially available components are employed.
Yet another object of the invention is to provide a rolled-type plate heat exchanger wherein the heat exchanger may be readily insulated and is of a -concise con figuration as to be easily installed within a compact hous ing or other type of refrigeration circuit shroud.
Yet another object of the invention is to provide a rolled-type plate heat exchanger wherein uniform distribution of the heat-exchanging medium is accomplished throughout the exchanger and wherein low resistance to flow through the heat exchanger, while maintaining a high heat-exchanging efficiency, is provided.
These and other objects of the invention arising from the details and relationships of the components of embodiments thereof will be apparent from the following description and accompanying drawings wherein:
FIG. 1 is an elevational view of the plate, tube and spacer wires, as assembled prior to the plate being rolled,
FIG. 2 is a plan view of the structure of FIG. l,
FIG. 3 is a plan view illustrating the relationships of cce the plate, tubes and spacer wires during the rolling of the heat exchanger,
FIG. 4 is a plan, sectional view of the completed heat exchanger assembly as taken along section IV-IV f FIG. 5,
FIG. 5 is an elevational view of the completed heat exchanger assembly,
FIG. 6 is an elevational, sectional view as taken along section VI-VI of FIG. 4,
FIG. 7 is an elevational view of another embodiment of heat exchanger employing the inventive concepts of the invention,
FIG. 8 is a plan, sectional view of the embodiment of FIG. 7 taken along section VIIIVIII thereof, and
FIG. 9 is an elevational, sectional view of the heat exchanger embodiment of FIG. 8 taken along section IX-IX thereof.
The basic component of the heat exchanger in accord with the invention is a plate 1t) of an elongated configuration having high heat transfer characteristics. Preferably, the plate 10 would be formed of copper or brass,
` and in one embodiment of the invention consists of sheet material .032 thick, l2 in height, and 96" in length. The plate Iii may be composed of a pair of plate elements overlapped and soldered together as at 12, FIG. 2. Whether the plate 1li is formed of two interconnected plate elements or is formed from a single plate element,
is a matter of choice and optional with regard to the concept of the invention. The plate 1i) is defined by end edges 14 and longitudinal edges 16.
In the embodiment of the invention shown in FIGS. 1 through 6, four header tubes are associated with the plate 10 and are transversely disposed thereto, preferably perpendicular to the length of the plate. A central tube 18 is brazed or soldered to one side of the plate at the center region thereof, and tube Ztl is afiixed to the other 4side of the plate in the manner which will be appreciated from FIG. 2. At one end region of the plate 10 a tube 22 is affixed, and at the other end a tube 24 is, likewise attached to the plate 10` on the opposite side thereof with respect to tube 22. Thus, one plate portion is define-d between tubes 18 and 22 and another plate portion is de-l fined between tubes 20 and 24. In the embodiment of FIGS. 7, 8 and 9, the tubes 22 and 24 are replaced by solid wires, as will be apparent from the description of' the embodiment of FIGS. 7, 8 and 9. Preferably, thev tubes -24 are closed at their lower ends, as represented in FIG. l, and the tube lower ends terminate at theV lower longitudinal edge 16. The upper ends of the tubes:
extend above the upper longitudinal edge 16 of the plate and may be provided with elbow fittings, as illustrated.
A plurality of evenly spaced spacer wires 26 are affixed to the plate 1t) in a parallel relationship to each other and parallel to the longitudinal length of the plate. The
spacer wires 26 between the header tubes 18 and 22 are all disposed on a common side of the plate 1l), as will be apparent from FIGS. l and 2. The spacer wires between the tubes 20 and 24 are disposed on the opposite side of the plate 1t), as will be apparent from FIG. 2. The inner ends 23 of the spacer wires do not extend to the tubes 13- and 20, but terminate short thereof.
The header tubes are provided with openings 3l) evenly spaced along the length thereof and so located as to be disposed intermediate adjacent spacer wires 26. This relationship will be apparent from FIG. l wherein the open ings defined in tubes 18 and 22 are shown. Similar openings are defined in the tubes 20 and 24 and are related to the spacer wires mounted on the left. side of the plate 10, in FIG. 2, in a manner corresponding to the relationship apparent from FIG. l.
The plate, tube and spacer wire assembly of FIGS.` l and 2 is placed in a 'simple fixture whereby the tubes ci 18 and Zt) may be rotated about an axis A lying within the plate 1), parallel to the tubes and intermediate the points of contact to the tubes to the plate, FIG. 3. Such a fixture can be readily formed by placing a pair of free end mandrels into the tubes 18 and 2li which are adapted to be rotated about an axis corresponding to axis A. The tubes 18 and 20 are rotated in a counterclockwise direction about the axis A, FIG. 3, to wind the plate around the tubes. Such winding will form the spiral convolutions of the plate which are apparent. If desired, a tension in the longitudinal direction of the plate El@ may be imposed upon the plate itl at the end edges 14, as indicated by the arrows, FIG. 3, which is in a direction opposite to the movement of the plate ends as the plate is wound, in order to maintain the plate wrinkle-free and to insure a tight winding of the plate. In FIG. 3 the plate 1t) is partially wound and the relationship of the components will be appreciated.
During winding the spacing wires 26 will determine the radial 'spacing of the plate layers. In a commercial embodiment, the wires 26 may be of 1/e diameter and are of copper and will, thereby, bend readily to conform to the spiral configuration. As will be apparent from FIG. 6, the spacer wires permit a uniform spacing between the plate coils and, thereby, insure uniform flow characteristics and fluid distribution.
When the plate 1f) is completely wound, the tubes 22 and 24 are brazed or soldered as at 32 to the adjacent outer plate portion to maintain the convolutions in the tightly wound condition. As will be apparent from FIG. 4, the tube openings 34) of tube 18 are in communication with the chamber 34, while the openings 30 defined in the header tube 20 are in communication with the charnber 36. The chamber 34 communicates with the spiral flow path leading to the inner tube 22 and the chamber 36 communicates with the spiral fiow path conveying fluid to the tube 24.
After the plate has been wound into the configuration shown in FIG. 4, an upper cover plate 4f) is placed on the upper edges 16 of the plate lll and a lower cover plate 42 is placed on the lower edges 16. The plates 40 and 42 are sealed to the upper and lower edges, respectfully, of the plate 1t) to seal the ends of the heat exchanger and to seal the adjacent flow paths with respect to each other. While the ends of the heat exchanger may be sealed by the plates 40 and 42, it is also possible to seal the ends by merely filling the ends of the heat exchanger With solder. Such an operation is possible, in that the uppermost and lowermost spacing wires 26 are adjacent the upper and lower edges 16 of the plate and, thus, with the upper and lower edges of the plate define a space readily adapted to receive solder or other sealing means such as epoxy, etc.
Thus, upon attaching fittings, such as the elbows 38 on the ends of the header tubes, a refrigerant may be introduced into the heat exchanger through the tube 22 and withdrawn therefrom by tube 18. A fluid to be cooled by the refrigerant, such as water, may be introduced into the heat exchanger through tube 20 and removed at tube 24. In this manner of connection, a counterfiow circuit is provided. If desired, a jacket 44 may encompass the heat exchanger for purposes of insulation and protection.
While the spacing wires 26 will prevent any significant transverse ow of the refrigerant or water relative to the plates, the fact that the header tube openings 30 communicate between each spacing wire prevents the flow through the heat exchanger from being restricted and insures uniform flow through the exchanger. lf it is desired that transverse intermingling of the fluid within a flow path be accomplished, the spacing wires 26 can be provided with holes, notches, or breaks to permit intermingling of the refrigerant or water within a common flow path. Of course, the basic purpose of the spacing wires 26 is to maintain a uniform spacing between the adjacent wound plate coils. It is conceivable that with improved Winding techniques the number of spacing Wires required can be reduced from the number shown and, in sorne instances, may be completely eliminated. However, as a presesure differential between the refrigerant circuit and the water circuit often exists, it will usually be desirable that spacing means of one type or another be used to strengthen the heat exchanger assembly and prevent undue inflation or collapse of the coile-d plate.
A variation of apparatus employed in the inventive concept of the invention is illustrated in FIGS. 7, 8 and 9. In these figures components similar to those previously described are indicated by primes.
The plate ltl, header tubes 18 and 2Q', and spacer wire assembly utilized in the embodiment of FIGS. 7, 8 and 9 is identical to that previously described except that rather than employing the outer header tubes 22 and 24, solid wires 46 are aixed to the ends of the plate 10. When the plate is fully wound the solid wires 46 are soldered to the outer plate coil as at 48 to maintain the wound configuration. The ends of the heat exchanger coil are enclosed as by end plates 40 and 42', respectively, or the ends may be soldered as previously mentioned. A plurality of holes 50 are defined in the heat exchanger plate 10 adjacent one of the wires 46, and a plurality of similar holes 52 are defined in t-he heat exchanger plate adjacent the other solid wire 46, FIG. 9. These holes are related to the spacer wires 26 as to be disposed intermediate the wires, as will be apparent from FIG. 9. A header tube 54 is disposed adjacent the holes 5t) and a header tube 56 is disposed adjacent the holes 52. The header tubes 54 and 56 are provided with a plurality of holes 58 which align with the respective holes defined in the plate adjacent the ends thereof, and the header tube holes and the plate holes are interconnected by short conduits 60. Thus, the configuration of the head exchanger embodiment of FIGS. 7, 8 and 9 will be appreciated from FIG. 7.
The refrigerant may be introduced into the heat exchanger through the header tube 54 and removed therefrom by `header tube 18. The water to be cooled may be introduced into the heat exchanger at tube 20 and removed at tube 56. The coiled plate -portion of the heat exchanger of the embodiment of FIGS. 7, 8 and 9 may be encased within a reinforcing and insulating jacket, if desired.
It will, therefore, be appreciated that the rolled plate heat exchanger of the invention utilizes the high efficiency characteristics of a plate exchanger while keeping the exchanger to a compact configuration and size. By varying the height of the plate and the length thereof, a Wide variety of capacities of heat exchangers may be provided without requiring major changes in the manufacturing equipment and technique. The flow path through the exchanger has been found to be of a non-restrictive nature, and a heat exchanger constructed in accord with the invention of a given capacity may be of a significantly smaller size, as compared with more conventional heat exchangers of similar capacity.
It is appreciated that various modifications to the invention may be apparent to those skilled in the art without departing from the spirit and scope thereof, and it is intended that the invention be defined only by the sco-pe of the following claims.
1. A heat exchanger comprising, in combination,
(a) a heat exchanging coil formed by a pair of spirally wound plate portions having ends and longitudinal edges, said plate portions being wound about a common axis in a like direction defining a pair of adjacently disposed spiral flow paths, said coil having a center and a periphery,
(b) a pair of first conduits extending into the center of said coil substantially parallel to the axis of said coil, said conduits ibeing located on opposite sides of said plate portions,
(c) a port dened in each of said first conduits within the contines of said coil and in communication with a ow path, whereby said rst conduits communicate with different ow paths,
(d) said longitudinal edge defining coil ends, means sealing the adjacent longitudinal edges of said plate portions to each other to thereby seal the ends of said coil,
(e) means sealing said -plate portion ends with respect to the adjacent outer plate portion forming a portion of the coil periphery,
(f) a pair of second conduits disposed adjacent the periphery of said coil,
(g) port means dened in each of said second conduits communicating with said flow paths adjacent said periphery, the port `of one of said second conduits communicating with one ilow path and the ports of the other second conduit communicating with the other flow path, and
(h) a plurality of spaced, parallel, elongated spacer elements axed to each of said plate portions spaced between and parallel to said longitudinal edges maintaining the radial spacing of the plate portions coils, said spacer elements on a common plate portion 'being located on a common side thereof and the spacer elements of one of said plate portions being on the opposite side thereof with respect to the spacer elements located Ion the other plate portions, said .spacer elements on each plate portion being spaced apart such a distance and related to the associated plate portion such that upon said plate portions being wound about said common axis spacer elements of one of said plate portions radially align with spacer elements of the other plate portion in the axial direction olf said coil, said spacer elements engaging the adjacent plate portion when wound about said common axis permitting said fiow paths to be adjacent each other and of a radial dimension corresponding to the radial dimension of said spacer elements.
2. A heat exchanger comprising, in combination,
(a) a heat exchanging coil formed by a pair of spirally wound plate portions having ends and longitudinal edges, said plate portions being wound about a common axis in a like direction dening a pair of adjacently disposed spiral ow paths, said coil having a center and a periphery,
(b) a pair of rst conduits extending into the center of said coil substantially parallel to the axis of said coil, said conduits being located on opposite sides of said plate portions and extending between the plate portion longitudinal edges,
(c) a plurality of ports defined in each of said rst -conduits axially spaced along the length of said conduits and in communication with a flow path whereby said rst conduits commuicate with different tlow paths,
(d) said longitudinal edges dening coil ends, means sealing the adjacent longitudinal edges of said plate portions to each other to thereby seal the ends of said coil,
(e) means sealing said plate portion ends with respect to the adjacent outer plate portion forming a portlon of the coil periphery,
() a plurality of spaced, parallel, elongated spacer elements aixed to each of said plate portions spaced between and parallel to said longitudinal edges maintaining the radial spacing of the plate portions coils, said spacer elements on a common plate portion being located on a common side thereof and the spacer elements of one of said plate portions being on the opposite side thereof with respect to the spacer elements located on the other plate portion, said spacer elements on each plate portion being spaced apart such a distance and related to the associated plate portion such that upon said plate portions being wound about said common axis spacer elements of one of said plate portions radially align with spacer elements of the other plate portion in the axial direction of said coil, said spacer elements engaging the adjacent plate portion when. wound about said common axis permitting said ilow paths to be adjacent each other and oit a radial dimension corresponding to the radial dimension of said spacer elements, said spacer elements being of a length substantially equal to that of the longitudinal length of the associated plate portion and subdividing said flow paths into a plurality of passages,
(g) a pair of second conduits disposed adjacent the periphery of said coil substantially parallel to the coil axis and aligned with the coil dimension de lined by said longitudinal edges, and
(h) a plurality of ports dened in said second conduits axially spaced along the length thereof, the ports of eaoh second conduit communicating with a different flow path and the ports of said first and second conduits being disposed intermediate said longitudinal edges as to lie intermediate adjacent spacer elements for communication with said flow paths passages.
3. ln a heat exchanger as in claim 2 wherein:
(a) said second conduits are located within the connes of the periphery of said coil.
`4. In a heat exchanger as in claim 2 wherein:
(a) said second conduits are located exteriorly of the connes of said coil,
(b) a plurality of openings detined in said plate portions adjacent said ends, said openings being located intermediate said spacer elements,
(c) said common conduit ports communicating with said openings.
References Cited UNITED STATES PATENTS 2,131,265 9/1938 Bichowsky 165--165 2,136,086 11/1938 Rosenblad 165-166 2,136,153 11/1938 Rosenblad 165--165 2,193,345 3/1940` Rosenblad 165--166 2,217,316 10/ 1940 Kallstenius 16S-167 FOREIGN PATENTS 1,058,090 11/1953 France.
835,008 3/1952 Germany.
778,541 7/ 1957 Great Britain.
102,545 9/ 1941 Sweden ROBERT A. OLEARY, Primary Examiner.
M. A. ANTONAKAS, Assistant Examiner.