Abstract:
A cooling device including an air source, preferably a fan, that provides air flow and a shroud for directing air flow from the air source at an object, particularly a coil of material, preferably a metal or metal alloy having a temperature greater than the ambient room temperature. The cooling device provides cooling efficiency by directing the air from the air source at an increased velocity to a desirable area or areas on an end surface of the object, thereby increasing heat transfer from the object. The cooling device shroud includes an air directing surface that influences the direction of air flow across the object in a desired pattern. Methods for preparing cooling devices and for cooling objects are also described.

Description:
CROSS REFERENCE 
     This is a U.S. patent application of U.S. provisional application 60/811,925, filed Jun. 8, 2006 for a Apparatus and Method for Coil Cooling, which is hereby fully incorporated by reference. 
     FIELD OF THE INVENTION 
     The present invention relates to a portable cooling device including an air source, such as a fan, that provides air flow, and a shroud for directing air flow from the air source at an article, particularly (a) a coil of material or (b) a non-coil metal article such a sheet, plate or ingot, having a temperature greater than the ambient room temperature. The cooling device provides cooling efficiency by directing the air from the air source at an increased velocity to a desirable area or areas on a surface of the object, thereby increasing heat transfer from the object. The cooling device shroud includes an air directing surface that influences the direction of air flow across the object in a desired pattern. Methods for preparing cooling devices and for cooling objects, particularly coils, are also described. 
     BACKGROUND OF THE INVENTION 
     In the metallurgical or metalworking field, sheets or pieces of a metal or metal alloy are processed in any number of ways that can raise the temperature of the sheet above the temperature of the ambient room temperature. The processed sheets are subsequently rolled into a coil. For example, sheets that have been treated using a cold rolling process can reach temperatures above 200° C. during the process. Heat treatments utilized to treat sheets include, but are not limited to, continuous annealing/solution heat treatment (SHT) and batch annealing. During a continuous annealing/SHT process, the sheet is uncoiled and then first passed through a furnace section and then a quench section. For some metals or alloys, the sheet comes off the quench at higher than room temperature. During batch annealing, the entire coil is placed in a furnace where it is heated to a predetermined temperature and held for a predetermined period of time, such as several hours, after which the coil is removed and allowed to cool. 
     Following a procedure such as, but not limited to, one of the above described procedures, it is often necessary to cool the sheet coils to ambient room temperature either as a final step prior to storing/shipping or the like, or in preparation for a subsequent step in a manufacturing sequence. 
     One current practice in the art is to provide forced air cooling by positioning an axial flow fan adjacent a coil and directing air flow at the coil. The air flow is generally perpendicular to the horizontal axis of the coil at the surface of the coil end, and the velocity of air is limited by the air exit velocity of the fan. When the coil has a hollow core or center, some of the air passes through the coil center and therefore does not contribute significantly to coil cooling. Furthermore, some of the air passes along the outside of the coil diameter and also does not provide efficient heat transfer. 
     SUMMARY OF THE INVENTION 
     The cooling device of the present invention comprises an air source and a shroud connected to the air source. The shroud includes an air directing surface having one or more apertures in an arrangement adapted to direct air from the air source at a predetermined area or areas on a surface of an article, such as a coil or a non-coil article, preferably of a metal or metal alloy. The shroud is utilized to direct air flow across a surface of the article to achieve more efficient cooling when compared to using the air source alone. In one embodiment, the shroud design increases the air velocity to a value greater than the velocity exit value from the air source such as a fan. In a further embodiment, the shroud includes an adaptor that allows the device to be utilized on a coil without a core, on a coil with a core, or with a coil having a mill spool which extends out beyond the plane of the coil sidewall or end. The adaptor prevents air from passing through the center of the coil. 
     In one embodiment, a cooling device having an air source is provided. A shroud of the device is positioned adjacent one lateral end of a coil, wherein air from the air source is directed through one or more apertures of an air directing surface of the shroud onto a surface of the coil, preferably near the inner diameter of the coil. The air flows in a gap between the surface of the coil and the air directing surface of the shroud toward the outer diameter of the coil, escaping along the end of the shroud or outer diameter of the coil. In another embodiment, the shroud air directing surface has an outer perimeter formed as an annulus, preferably having a diameter similar to the diameter of the coil. In a preferred embodiment, the adaptor of the shroud prevents air from flowing through the center of the coil. 
     It is, therefore, an object of the present invention to provide a cooling device that is mobile, portable, and can be easily positioned in relation to a coil in order to cool the coil for further handling or processing or a combination thereof. 
     A further object of the present invention is to provide a cooling device and method for utilizing the cooling device that improves heat transfer and cooling efficiency when compared to the prior art practice of providing forced air cooling by directing air from an axial flow fan at the lateral end of a coil. 
     Yet another object of the present invention is to provide a cooling device that is adapted to be utilized on a coil free of a core, on a coil with a core, or on a coil having a mill spool which extends out beyond the plane of an end of a coil. 
     Still another object of the present invention is to provide a shroud that can be easily retrofitted to an existing fan. 
     It is a further object of the present invention to provide a cooling device that utilizes air from an air source, increases the velocity of the air exiting the air source, and directs the air at a location near the inner diameter of a coil and subsequently along the surface of the coil. 
     Accordingly, one aspect of the present invention is a cooling device for use in cooling an article, comprising an air source that provides air flow, and a shroud that receives air flow from the air source and is adapted to direct the air onto a surface of the article, wherein the shroud includes a receiver that is connected to an air exhaust outlet of the air source, wherein the shroud includes an air directing surface having one or more apertures through which air flows out of the shroud, and wherein the one or more apertures have a total cross-sectional area that is less than a cross-sectional area of the air exhaust outlet. 
     Another aspect of the present invention is a cooling device for use in cooling a coil of material, comprising an air source that provides air flow through an air exhaust outlet, and a shroud connected to the air source that receives air from the air source exhaust outlet and is adapted to expel the air through one or more apertures of an air directing surface of the shroud, wherein the shroud includes an adaptor connected to the air directing surface of the shroud and adapted to substantially seal a core of the coil to prevent air flow through the core. 
     Still another aspect of the present invention is a method for cooling a coil, comprising the steps of providing a coil of material at a temperature above an ambient temperature, providing a cooling device comprising an air source that provides air flow and a shroud that receives air flow from the air source and is adapted to direct the air onto a surface of the coil, wherein the shroud includes a receiver that is connected to an air exhaust outlet of the air source, wherein the shroud includes an air directing surface having one or more apertures through which air flows out of the shroud, positioning the air directing surface of the cooling device adjacent an end of the coil, and directing air from the cooling device onto the coil end to cool the coil, wherein a velocity of the air exiting the one or more apertures is greater than a velocity of the air exiting the air exhaust outlet. 
     Yet another aspect of the invention is a cooling device for use in cooling an article, comprising an air source that provides air flow; and a shroud that receives air flow from the air source and is adapted to direct the air onto a surface of the article, wherein the shroud includes a receiver that is connected to an air exhaust outlet of the air source, wherein the shroud includes an air directing surface having one or more apertures through which air flows out of the shroud, wherein the air directing surface is substantially planar radially outward of an adaptor connected to the air directing surface and wherein the air directing surface is adapted to be positioned substantially parallel to a plane formed by an end of the article. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be better understood and other features and advantages will become apparent by reading the Detailed Description of the Invention, taken together with the drawings, wherein: 
         FIG. 1  is a side elevational view, in partial cross-section, of one embodiment of a cooling device of the present invention positioned adjacent to the lateral end of a coil; 
         FIG. 2  is a partial side elevational schematic view of the cooling device of the present invention, particularly illustrating air flow through apertures of the device onto a surface of a coil; 
         FIG. 3  is an elevational front view of one embodiment of a shroud of a cooling device of the present invention taken through line  3 - 3  of  FIG. 1 , particularly illustrating an air directing surface having apertures through which air can flow; and 
         FIG. 4  is a side elevational view, in partial cross-section, of one embodiment of a cooling device of the present invention having a flexible shroud, positioned adjacent to the lateral end of a coil. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     This description of preferred embodiments is to be read in connection with the accompanying drawings, which are part of the entire written description of this invention. In the description, corresponding reference numbers are used throughout to identify the same or functionally similar elements. Relative terms such as “horizontal,” “vertical,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing figure under discussion. These relative terms are for convenience of description and are not intended to require a particular orientation unless specifically stated as such. Terms including “inwardly” versus “outwardly,” “longitudinal” versus “lateral” and the like are to be interpreted relative to one another or relative to an axis of elongation, or other axis, as appropriate. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. The term “operatively connected” is such an attachment, coupling or connection that allows the pertinent structures to operate as intended by virtue of that relationship. 
     Referring now to the drawings, the cooling device  10  of the present invention includes an air source  20  operatively connected to a base  50  in one embodiment as shown in  FIG. 1 . Air source  20  is utilized to generate or create air flow at a velocity for use by cooling device  10 . Air source  20  is generally a fan having a housing  22 , an air intake  23 , and an air exhaust outlet  24 . Air source  20  further includes a motor  25  operatively connected to housing  22 . Motor  25  is preferably an electric motor operatively connected to an electrical switch. In one embodiment, motor  25  is operable at one or more different speeds. 
     An impeller or propeller  26  is operatively connected to an output shaft of motor  25 . Propeller  26  includes one or more fan blades utilized to draw air into air intake  23  and expel the same through air exhaust outlet  24 . The described air source  20  is known to those of ordinary skill in the art and is commercially available from sources such as Universal Fan and Blower of Bloomfield, Ontario, Canada and Continental Fan of Buffalo, N.Y., USA. There are generally no limitations regarding the horsepower of the fan, so long as the desired air flow is provided to cool a coil  100 . A fan having a horsepower of less than 10 is utilized in this application in one embodiment to maintain ease of portability. In a preferred embodiment, an air source is utilized that is capable of maintaining relatively low flow rates at medium to high pressure without stalling or overloading, with an appropriate shroud design. 
     During use, a motor switch is actuated and motor  25  is energized, thereby producing rotation of propeller  26 . The rotation of propeller  26  draws air inwardly through air intake  23  and discharges the air through exhaust outlet  24 . 
     While the air source  20  described hereinabove is generally known in the art as an axial flow fan, any other air source such as a blower, a pump such as a rotary or centrifugal pump, a compressor, centifugal-blower or fan, tube-axial fan, or mixed flow fan, or the like can be utilized to provide a desired volume of air at a desired velocity to shroud  30  of cooling device  10 . 
     Shroud  30  is connected to air source  20  and receives air expelled from exhaust outlet  24 , as shown in  FIG. 2 . Receiver  32  of shroud  30  extends around a perimeter of air exhaust outlet  24  and channels air through one or more internal guide vanes  33  into interior  34  of shroud  30 . The connection between receiver  32  of shroud  30  and air exhaust outlet  24  or housing  22  of air source  20  is airtight or substantially airtight in order to provide efficiency of airflow through cooling device  10 . Any means known in the art can be utilized to connect shroud  30  to air source  20 , such as a pressure fit, a latch, fasteners such as screws or nuts and bolts, adhesive, or the like, with a latch being preferred. In one embodiment, receiver  32  is an annular rim or flange conforming to the perimeter of air exhaust outlet  24  which typically has an annular opening. 
     Shroud  30  includes a body  36  that extends between receiver  32  to the shroud air directing surface  40  as shown in  FIGS. 1 and 2 . Shroud body  36  as illustrated is formed as a frustoconical structure. A first end of body  36 , namely at receiver  32  forms a plane that is generally parallel to a plane at the second end of body  36  at air directing surface  40 . Body  36  is not limited to the frustoconical shape shown, but can have any other desired configuration so long as receiver  32  is connected to air directing surface  40 . Accordingly, body  36  can be cylindrical, rectangular, square, or the like, or combinations thereof. The function of body  36  is to transfer air received from air exhaust outlet  24  through apertures  42  of air directing surface  40 . 
     In a preferred embodiment, the direction of air flow  60  is changed from horizontal, i.e. the direction of air flow entering outlet  24  from air source  20 , towards a direction substantially perpendicular or perpendicular thereto, such as shown in  FIG. 2 , in a gradual fashion to minimize the pressure drop and maximize the air velocity through the shroud  30 . Air flow channeling and directing is particularly important in an application utilizing an axial fan which typically does not develop high pressure. Use of guide vanes  33  attached to the shroud  30  to help direct the air flow, such as shown in  FIG. 2  is preferred in one embodiment. Cap or adaptor  44 , as described hereinbelow, can also be contoured to aid in directing air flow. Known design principles of fluid dynamics can be applied to design the shape required for each application. In one embodiment, one or more air directing vanes such as spiral swirl vanes  43 , as shown in  FIG. 3 , are incorporated on the coil side of the shroud  30  to increase the contact time and contact area of the cooling air with the coil  100 . 
     In a preferred embodiment, several straight or curvilinear vanes  43 , preferably of the same width as projection  46 , are attached to the air directing surface  40  and extend from the edge of the air exit openings towards the outer diameter or perimeter  48  and cause the air to take a curving path across the coil face. Also, the distance maintained between the coil  100  and the shroud  30  is very important in the process for cooling a coil  100 , and depends on the fan characteristics, i.e. pressure vs. flow, generally known as the fan characteristics curve. Accordingly, the distance between the coil  100  and shroud  30 , such as at air directing surface  40 , can be varied depending on the application. 
     In a further embodiment, shroud  30  is a substantially solid structure, but can include flexible elements in order to provide a desired air flow to a coil  100 . Portions of the shroud  30  can be formed of generally any suitable material offering a desired rigidity or form, including, but not limited to, a polymer, a rubber, or an elastomer, either thermoplastic or thermoset, such as PVC; or any suitable metal. A requirement of shroud  30  is that the material chosen must be suitable in order to withstand and substantially not deform, degrade or the like, at the temperature of the coil  100  to be cooled, for a period of time. 
     As stated herein above, shroud  30  includes air directing surface  40  connected to body  36 . Air directing surface  40  is adapted to be placed in close proximity to a coil  100  as illustrated in  FIG. 1  in order to aid in heat transfer and cooling of the coil to a preferred temperature such as room temperature. Air directing surface  40  has a configuration adapted to direct air flow across a surface of the coil, preferably between coil lateral end surface  102  and the outer surface of air directing surface  40 . 
     Air directing surface  40  includes one or more apertures  42 . As illustrated in  FIG. 3 , a plurality of apertures  42  are shown arranged around an adaptor  44  in the radial interior portion of air directing surface  40 . Any number of apertures can be utilized with, generally from 1 to about 16, desirably about 6 to about 10, and preferably about 8 apertures present. It is desirable in one embodiment of the present invention that the cross-sectional area of all of the apertures present on air directing surface  40  be less than the cross-sectional area of the air exhaust outlet  24  in order to provide an increase in air velocity through the apertures collectively when compared to air exhaust outlet  24  in order to provide improved heat transfer between the air and the coil, according to heat transfer theory. 
     In a preferred embodiment, a plurality of apertures  42  are spaced around the circumference of adaptor  44 . In this alignment, the air flowing out of apertures  42  is directed onto the interior portion of lateral end surface  102  of coil  100  adjacent to spool  104  thereof. As illustrated in  FIG. 2 , air flow travels along lateral end surface  102  radially outwardly toward the outer diameter of coil  100 . The size and number of apertures are matched to the fan characteristics curve and shroud design. In one embodiment, the total area of the apertures ranges generally from about 50% to about 90%, desirably about 60% to about 70%, and preferably about 66% of the area of the air exhaust outlet  24 . The area of an imaginary annular cylinder extending between the coil end and the shroud at the outer diameter of the apertures is preferably 1 to 3 times less and most preferably 1.5 times less than the total area of the apertures. In a preferred embodiment, adaptor  44  includes projection  46  extending outwardly from air directing surface  40  and is adapted to be placed near and preferably abutted against coil  100 . Preferably, projection  46  is substantially annular, or annular with a perimeter thereof extending completely around the coil core or mill spool  104 . The diameter of the projection is dependent on the size of the core or mill spool  104 . Accordingly, air is prevented from passing through the core of coil  100  or mill spool  104  about which coil  100  is wound. Projection  46  is further adapted to allow for a portion of a coil core such as a mill spool to be situated therein, should the mill spool  104  extend beyond the end of the coil  100 . 
     Perimeter  48  of air directing surface  40  is preferably annular although it is to be understood that other shapes or designs can be utilized. Annular perimeter  48  is utilized as the same is complimentary to the shape of lateral end surface  102  of coil  100  which is also typically annular. In one embodiment, an annular perimeter  48  has a diameter that is about 5% less than the diameter of a coil  100 , and at a minimum, is about 66% of the distance between the coil inner diameter and the coil outer diameter. The cooling device is situated adjacent the coil in one embodiment such that the area of the imaginary annular cylinder extending between the coil and the shroud at the outer diameter of the apertures  42  is preferably about 20% to about 60% of the area of exhaust outlet  24 . 
     Base  50  or other suitable mount is utilized to support air source  20  and shroud  30 . The structure of base  50  is not critical, so long as the air source  20  and shroud  30  are supported and allowed to perform their intended functions. In one embodiment as illustrated in  FIG. 1 , base  50  includes one or more legs interconnected by a frame  54 . In a preferred embodiment, base  50  includes one or more wheels  56  that are operatively connected to frame  54 , or leg  52  as shown in  FIG. 1 . Wheels  56  of base  50  allow cooling device  10  to be portable and easily moved to a desired position in relation to a coil or other object to be cooled. Wheels, if any, are provided with a lock to prevent the fan from moving away from the coil due to pressure in a preferred embodiment. Base  50  is constructed of any suitable materials or combinations of materials including, but not limited to, metal, polymer, wood, or the like. 
     In one embodiment such as shown in  FIG. 4 , a cooling device  210  is provided having a shroud  230  having at least a portion thereof that is flexible. When shroud body  236  or other portion of shroud  230  is flexible, on either all or a part thereof, various materials can be utilized, including, but not limited to, plastic or fabric such as fabric including ducting with a support such as a spiral-wound spring-wire, or the like. 
     Flexible shroud  230  includes a receiver  232  that is connected to air exhaust outlet  224  of axial fan  220  to receive air therefrom and direct air into interior  234  of shroud  230 . As described above, axial fan  220  includes an air inlet  223 , motor  225  and propeller  226 . The end of flexible shroud  230  generally opposite axial fan  220  is detachably connected to an air directing surface  240  via a locking mechanism  245  that permits quick disassembly for ease of handling. Air directing surface includes an adaptor  244  and one or more projections  246  of adaptor  244  that can be operatively attached to a spool plug component that optionally extends outwardly from the coil. The adaptor  244  can be moved towards or away from the coil to make a desired seal with the spool  104 . As also described hereinabove, air directing surface  240  includes one or more apertures  242  that direct air into the coil  100 . Air directing surface  240  can include one or more air directing vanes as described hereinabove. 
     Adaptor  244  in one embodiment as shown in  FIG. 4  has an elongated, preferably annular, projection  246  that extends into mill spool  104 , that is also typically annular. The elongated projection  246  has a length sufficient to support air directing surface  240  on coil  100 . In a preferred embodiment, the elongated projection  246  has an outer diameter slightly less than the inner diameter of mill spool  104  for a snug or friction fit. 
     Adaptor  244  provides support for air directing surface  240  and can rest on mill spool  104  or otherwise be operatively connected thereto. 
     The flexible shroud  230  advantageously allows the cooling device  210  to be utilized on coils having different core heights above a ground surface. For example, in one embodiment, air directing surface  240  is operatively connected to a core of a coil to be cooled such as shown in  FIG. 4 , with the core situated at a particular height above the ground surface due to the radius of the coil as well as the height of any object the coil is situated on, if any. Depending on the height of the air directing surface  240  operatively connected to the coil, the end of flexible shroud  230  opposite receiver  230  is moved upward or downward and subsequently connected to air directing surface  240  using locking mechanism  245 . Accordingly, depending on the height of the core above a ground surface, the outer surface of flexible shroud body  236  between receiver  232  and air directing surface  240  can have a curved appearance. 
     Cooling device  210  includes a base  250  that supports air source  220 . In one embodiment, base  250  includes one or more wheels  256  operatively connected to frame  254  or leg  252  such as shown in  FIG. 4 . As described hereinabove, wheels  256  can be provided with a lock to prevent the fan  220  from moving away from the coil  100 . 
     In order to utilize cooling device  10  of the present invention, cooling device  10  is moved into a desired position in relation to a coil  100 , such as illustrated in  FIGS. 1 and 2 . Preferably, projection  46  is aligned over or around spool  104  of coil  100  forming a seal to prevent air flow therethrough. Air source  20  is actuated and air flows through air exhaust outlet  24  into interior  34  of body  36  of shroud  30 . Air flows out of interior  34  through one or more apertures  42  toward lateral end surface  102  of coil  100 . Since the air flow cannot deeply penetrate lateral end surface  102 , the forced air continues to flow radially outward toward the outer diameter of coil  100  between air directing surface  40  and lateral end surface  102 . The air flow is generally perpendicular to the horizontal axis of the coil. Shroud  30  increases air velocity from the air source, thereby increasing the heat transfer. In an alternative embodiment, the power required for the air source  20  may be reduced for equivalent cooling capacity since utilization of the cooling air is more efficient. Shroud  30  and base  50  can be easily retrofitted to existing air source  20 . 
     Articles that can be cooled by the present invention include any material, such as a coil or a non-coil article, preferably a metal or metal alloy. Non-coil metal articles include examples such as a sheet, plate, or ingot. Sheet material utilized to form coil  100  can have any thickness. However, in general air cooling of the type desired herein is most efficient with thinner material due to the larger number of windings per coil. Air gaps and surface roughness between laps tend to provide an insulating effect. The more of these discontinuities there are, the more heat movement and thus cooling is favored in the axial direction. In a preferred embodiment, coil  100  is aluminum or an aluminum alloy. Generally any of the numerous one or more 1xxx through 9xxx series alloy articles such as, but not limited to, sheets, plates, coils, and ingots according to the Aluminum Association Designation for Wrought Aluminum Alloys can be utilized. Coil  100  preferably has a side surface  106  having a perimeter that is circular, although side surfaces of other configurations which are not circular, but are substantially circular, oval, or the like can also be utilized. As described herein, coil  100  can have a center or core comprising a spool  104  that is hollow or solid. Coil  100  can be wound upon a mill spool  104  which can be of any suitable composition such as steel, aluminum or fiber. While coil  100  can generally have any diameter, typical diameters range from about 76.2 cm (30 inches) to about 25.40 cm (100 inches), and spools typically vary between about 20.3 cm (8 inches) to about 122 cm (48 inches), but can be smaller or larger. 
     In accordance with the patent statutes, the best mode and preferred embodiment have been set forth, the scope of the invention is not limited thereto, but rather by the scope of the attached claims.