Abstract:
A system is provided for forming an ice coating on the outer surface of blown glass tube-shaped glass pieces ( 30 ) of an art work. The blown glass tubes are attached to a support surface ( 36 ) such that opposing ends of each glass tube are positioned over apertures in the surface. Liquid coolant contained in a thermally insulated tank ( 10 ) is cooled by a compressor ( 12 ) and then forced through an inlet manifold subassembly ( 20, 24 ) into the glass tubes, and then returned through a return manifold subassembly ( 40,44 ) to the tank for re-circulation. The continuous flow of liquid coolant results in the formation of an ice coating on the outer surface of the blown glass tubes.

Description:
FIELD OF THE INVENTION 
     This invention relates generally to the art of producing blown glass articles, and more particularly to a system and method for controlling the formation of an ice coating on the outer surface of such articles. 
     BACKGROUND OF THE INVENTION 
     The art of glass blowing is well known, it has been practiced throughout the world for centuries. Present day glassblowers manipulate hot, malleable glass by using similar skills and techniques as those used by Egyptian craftsmen of ancient times. In the hands of an experienced glassblower, glass can be manipulated into a virtually endless variety of geometries and sizes. Glass blowing is commonly used to create artistic glass works for both private and public display. There is great demand in the marketplace for such works. 
     Artists create visually appealing blown glass works by manipulating the physical characteristics of the glass work. Primarily, visual variations from piece to piece are limited to differences in geometric configurations, color combinations, and surface characteristics of the individual glass components of the work. Those skilled in the art of creating blown glass works are constantly looking for ways to further enhance the creativity of their works. Accordingly, novel ways of enhancing the visual appeal of artistic glass works are desirable. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a system and method for manipulating the visual appearance of a hollow glass article by controlling the temperature of a fluid communicated therethrough. 
     It is another object of the present invention to provide a system and method for forming an ice coating on the outer surface of a hollow glass article in an above-freezing temperature ambient condition. 
     It is still another object of the present invention to provide a system and method for preventing the formation of an ice coating on the outer surface of a hollow glass article in a below-freezing temperature ambient condition. 
     These and other objects are achieved with the present invention in which a system and method are provided for controlling the formation an ice coating on the exterior of hollow glass members  30  of an artwork. The individual glass members  30  are preferably blown from molten glass to create a plurality of unique tubular geometries having a variety of colors. 
     The glass members  30  have opposite open ends, each terminating at a planar edge  31  defining an opening  33 . The opposite ends of each glass tube are attached to a support structure  34  preferably having a planar upper surface  36  surrounded by a raised peripheral portion  38 . Planar edge  31  of tubular glass member  30  is preferably attached to surface  36  with a layer of adhesive  32 , providing an air-tight waterproof seal between glass member edge  31  and support surface  36 . 
     The ends of each glass tube  30  are positioned over apertures  37  extending completely through support structure upper surface  36 . Connector members  26  are provided for transferring liquid coolant between the glass members  30  and other components of the system. In the preferred embodiment of the present invention, each connector  26  has upper and lower conduit portions,  27  and  29 , respectively, separated by a flanged portion  28  extending outwardly from the exterior surface of the connector. 
     An insulated reservoir  10  is provided for holding a volume of liquid coolant to be circulated through the system. In operation, the temperature of the liquid coolant can be reduced to a desired temperature range using a compressor apparatus  12  similar to that employed in automobile air conditioning systems and refrigeration systems. As illustrated in FIG. 4, in the present invention, compressed refrigerant is circulated through a length of copper tubing  14  which includes a coiled section extending proximate to the bottom of coolant reservoir  10 . A pump  18  is provided for circulating the coolant through the system during operation. 
     A conduit subassembly is provided for directing the flow of coolant through the system. Generally, the conduit subassembly includes an inlet manifold  20 , a plurality of inlet conduit members  24 , an outlet manifold  44 , and a plurality of outlet conduit members  40 . Inlet manifold  20  includes a plurality of integral manifold ports  22  fluidly connected to inlet conduit members  24 . Preferably, inlet conduit members  24  comprise lengths of flexible plastic tubing capable of circulating coolant at the desired temperature ranges without degrading. Opposite ends of each inlet conduit member  24  fit snugly over integral port  22  and fluid connector portion  29 , respectively. Outlet manifold member  44  has a similar construction to inlet manifold member  20  and includes a plurality of integral outlet ports  42  attached by outlet conduit members  40  to corresponding fluid connectors as previously described above. Preferably, the outlet conduit members  40  are provided having a smaller inner diameter than the respective inlet conduit members  24  in order to impede the flow of coolant through the glass tubes, thereby ensuring that the glass tubes are maintained continuously filled with coolant during operation. In this manner, the formation of bare spots, or external tube surface areas not coated with ice, can be minimized. Outlet manifold member  44  also has an integral return port  46  through which the coolant is returned to coolant reservoir  10 . As illustrated in FIGS. 1 and 4, return port  46  introduces circulated coolant back to the surface of the coolant volume in reservoir  10 . 
     In an alternate embodiment of the present invention, a thermocouple apparatus extends through reservoir  10  for measuring coolant temperature. More specifically, the thermocouple includes a temperature sensor  17  and a temperature display  19 . Preferably, the thermocouple communicates electronically with the compressor subsystem in such a manner that operation of the compressor can be regulated to maintain the coolant temperature within a desired range. 
     In operation, the compressor apparatus  12  reduces the temperature of liquid coolant in the reservoir  10  to a desired temperature. Once the desired coolant temperature has been achieved, coolant is pumped out of reservoir  10  and into inlet manifold  20 . Subsequently, the coolant is forced through integral manifold ports  22  and directed into corresponding glass members  30 . Upon exiting the glass members, coolant is recombined in outlet manifold  44 , where it is returned into reservoir  10  through outlet port  46 . Preferably, the system is operated in an environment having a high ambient temperature relative to the coolant temperature. As a result, condensate is initially formed on the outer surface of the glass tubes, ultimately freezing to form the desired ice coating. 
     Alternatively, in some instances it may be desirable to prevent the formation an ice coating on the exterior surface of glass members  30  in below-freezing temperature ambient conditions. In that instance, coolant is preferably circulated through the system at a temperature sufficient to preclude the formation of an ice coating. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 a perspective view, partially cutaway, of a system for forming an ice coating on glass articles, in accordance with the present invention; 
     FIG. 2 is a perspective view of an end of a glass member of the present invention; 
     FIG. 3 is an exploded view at a one end of a glass article of the present invention, further illustrating the preferred assembly of the glass article and connector member to the support structure; 
     FIG. 4 is a perspective view of reservoir  10  cross sectioned along the front side to expose the inside of the reservoir. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to FIGS. 1-4, a system is provided for controlling the formation of an ice coating on the exterior of tubular glass members  30  of an artwork. More specifically, the system provides a means for communicating a temperature-controlled fluid through the glass members to either effect the formation of an ice coating or, alternatively, to prevent the formation of an ice coating. In the preferred embodiment of the invention, the temperature-controlled fluid comprises liquid coolant. The individual tubular glass members  30  are preferably blown from molten glass to create a plurality of unique tubular geometries having a variety of colors. Applying the art of glass blowing to form such colored tubular members is well known. Accordingly, further description of the glass blowing process is not necessary to practice the invention and is not provided. 
     The glass members  30  have opposite open ends, each terminating at a planar edge  31  defining an opening  33 . The opposite ends of each glass tube are attached to a support structure  34 . In the preferred embodiment of the invention, the support structure has a planar upper surface  36  surrounded by a raised peripheral portion  38 . The support structure can be constructed from a variety of different materials including, but not limited to, wood, glass, plastic and metal. However, it is preferred that the support structure is constructed from a translucent material, such as glass, to enable the transmission of light emitted from a light source (not shown) through upper surface  36 . Planar edge  31  of tubular glass member  30  is preferably attached to surface  36  with a layer of adhesive  32 . It will be apparent to those skilled in the art that there are a variety of commercially-available adhesives that can be used for attaching the tubular glass members  30  to the upper surface  36  of support structure  34 . The adhesive should provide an air-tight, waterproof seal between glass member edge  31  and support surface  36 . Furthermore, the adhesive should be able to withstand the temperature extremes to which the glass tubes are subjected without degrading the efficacy of the seal. For instance, I have found success employing an ultraviolet (UV) curable epoxy sold under the trade name LUCTITE 349, manufactured by the Luctite Corporation of Rocky Hill, Conn. 
     As illustrated in FIG. 3, the ends of each glass tube  30  are positioned over apertures  37  extending completely through support structure upper surface  36 . Connector members  26  are provided for transferring liquid coolant between the glass members  30  and other elements of the system (described below). It will be apparent to those skilled in the art that various types of fluid connectors could be employed. In the preferred embodiment of the present invention, each connector  26  has upper and lower conduit portions,  27  and  29 , respectively, separated by an outwardly extending flanged portion  28 . As assembled, the flanged portion  28  is preferably attached to upper surface  36  of support structure  34  using an adhesive. Alternatively, attachment of the connector to the support structure could be accomplished using conventional mechanical fastening means. 
     A reservoir  10  is provided for holding a volume of liquid coolant intended for circulation through the system. As will be apparent to those skilled in the art of coolant systems, there are myriad coolant compositions that can be used with the present invention. For instance, I have found success using conventional automobile antifreezes having freezing temperatures of −30° C. and below. In FIG. 4, the surface level of the coolant is denoted by the letter S. Preferably, the reservoir has an insulated construction for maintaining the desired coolant temperature during operation. For example, conventional recreational coolers, such as those sold under the trade name IGLOO, provide adequate insulation. The size requirements of the reservoir can vary depending upon the circulation requirements of the particular system. 
     A conventional compressor subsystem  12  is provided for reducing, and subsequently maintaining, the temperature of the coolant within a desired temperature range. Compressor systems such as that employed in the present invention are commonly used in automobile air conditioning systems and refrigeration systems. Accordingly, a detailed description of the compressor system is not necessary to practice the present invention and is not provided. Generally, a refrigerant such as that sold under the trade name FREON, is compressed and circulated through a length of copper piping. As illustrated in FIG. 4, in the present invention, compressed refrigerant is circulated through a length of copper tubing  14  which includes a section extending proximate to the bottom of coolant reservoir  10 . Although the section of copper tubing extending along the bottom of the reservoir is illustrated running in a serpentine pattern, this feature of the invention is not intended to be limiting. For example, the section of copper tubing extending along the bottom of coolant reservoir  10  can have a coil-shaped pattern. As a result of maintaining the main section of copper tubing near the bottom of the reservoir, there is a decreasing coolant temperature gradient from the surface, S, of the coolant toward the bottom of the reservoir. 
     A pump  18  is provided for maintaining the circulation of liquid coolant through the system during operation. It will be apparent to those skilled in the art that a variety of different pump types and sizes can be employed with the present invention. I have found success using a 115 VAC, single phase, 60 Hz thermally-protected pump (catalog no. R106) manufactured by Water Ace Pump Co. of Ashland, Ohio. 
     As will now be described in more detail, a conduit subassembly is provided for directing the flow of coolant through the system. Generally, the conduit subassembly includes an inlet manifold  20 , a plurality of inlet conduit members  24 , an outlet manifold  44 , and a plurality of outlet conduit members  40 . 
     Inlet manifold  20  is preferably manufactured from a durable thermally insulating polymer such as polyvinyl chloride (PVC) and includes a plurality of integral manifold ports  22  fluidly connected to the inlet conduit members  24 . Preferably, inlet conduit members  24  comprise lengths of flexible plastic tubing capable of circulating coolant at the desired operational temperatures without degrading. For instance, the preferred tubing should be capable of circulating coolant at temperatures of about −20° C. to about −40° C., without degrading. It will be apparent to those skilled in the art that there are numerous commercially available flexible tubing materials that can be employed for this purpose. Opposite ends of each inlet conduit member  24  fit snugly over integral port  22  and fluid connector portion  29 , respectively. A conventional clamp member (not shown) can be used to further secure the ends of each inlet conduit member to the respective inlet ports and fluid connectors. 
     Outlet manifold member  44  has a similar construction to inlet manifold member  20  and includes a plurality of integral outlet ports  42  attached by outlet conduit members  40  to corresponding fluid connectors as previously described above. Preferably, the outlet conduit members  40  are provided having a smaller inner diameter than the respective inlet conduit members  24 . Consequently, the rate at which a volume of liquid coolant enters each glass tube member  30  is greater than the rate at which the same volume of liquid coolant exits the glass tube member. In this manner, the glass members are maintained continuously filled with coolant during operation to eliminate the occurrence of bare spots, or external surface areas not coated with ice, during operation. Outlet manifold member  44  has an integral return port  46  through which the coolant is returned to coolant reservoir  10 . As illustrated in FIGS. 1 and 4, return port  46  introduces circulated coolant back to the surface, S, of the coolant volume in reservoir  10 . 
     In an alternate embodiment of the present invention, a thermocouple apparatus extends through reservoir  10  for measuring the coolant temperature. More specifically, the thermocouple includes a temperature sensor  17  and a temperature display  19 . Preferably, the thermocouple also communicates electronically with the compressor subsystem  12  in such a manner that operation of the compressor can be regulated to maintain the coolant temperature within a desired range. 
     The operation of the system of the present invention will now be described in more detail. As previously described, the system can be operated to form an ice coating on the exterior of a glass article  30 , as well as to prevent the formation of such an ice coating. 
     In the former case, where the system is operated to form an ice coating, the compressor subsystem initially reduces the temperature of liquid coolant in the reservoir  10  to a desired temperature or temperature range. The desired coolant temperature can vary depending upon a number of factors including, but not limited to, the ambient conditions and the number and size of glass members to be ice coated. However, for a given system the rate of formation of the ice coating increases as the temperature of the circulated coolant is decreased. Generally, the temperature of the circulated coolant is maintained in the range of about −10° C. to about −40° C., and preferably at a temperature below about −20° C. 
     Once the desired coolant temperature has been achieved, coolant is pumped out of reservoir  10  and into inlet manifold  20 . Subsequently, the coolant is forced through integral manifold ports  22  and directed into corresponding glass members  30 . Upon exiting the glass members, coolant is recombined in outlet manifold  44 , where it is returned into reservoir  10  through outlet port  46 . As the coolant is circulated through the system, condensate forms on the outer surface of the glass members, ultimately freezing to form the desired ice coating. 
     During circulation through the system the coolant temperature increases. Preferably, this warmed coolant is returned to the surface of the body of coolant in the reservoir such that the volume of coolant in the reservoir has a decreasing temperature gradient from the surface toward the bottom. By drawing coolant from the bottom of the reservoir, the temperature of the returned coolant is gradually decreased to the desired temperature before being re-circulated through the glass tube members  30 . 
     Alternatively, in some instances it may be desirable to prevent the formation of an ice coating on the exterior of the glass members  30  under below freezing ambient conditions. In that instance, the system is operated in much the same manner as previously described, with the exception that the coolant is preferably circulated through the system at a temperature sufficient to preclude the formation of said ice coating. 
     While the preferred embodiments of the invention have been illustrated and described, it will be clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as described in the claims. For example, although the glass members  30  are illustrated attached to a support member surface  36  having a horizontal plane, other orientations are possible. In particular, the flexibility of conduit members  24  and  40  enable support surface  36  to be rotated to any desired orientation. For example, support surface  36  can have a vertical orientation where the artwork is displayed extending outwardly from a wall.