Patent Publication Number: US-2002011482-A1

Title: Infrared heating device for prewarming water

Description:
[0001] This invention is a continuation-in-part of the Provisional U.S. patent application Ser. No. 09/478,279 filed on Jan. 5, 2000, U.S. Pat. No. 6,261,261 issued Jul. 17, 2001 entitled “Infrared Heating Device for Prewarming IV Solutions”.  
    
    
     
       BACKGROUND OF THE INVENTION  
       [0002] 1. Technical Field of the Invention  
       [0003] The present invention relates to devices for preheating water prior to dispensing from a hot water tap or vlave, and more particularly to a disposable cassette having an infrared heating element electively powered for heating water in a pipe prior to dispensing so that hot water is dispensed immediately.  
       [0004] 2. Background of the Invention  
       [0005] It has been found that the distance form a hot water heater to a dispensing tap, as at a sink, a shower or a bath, is normally sufficiently far so that it can take a significant amount of time after a hot water tap is opened and before the hot water is dispensed. Thus there is a need for an inexpensive and reliable infrared device for prewarming water in a pipe immediately prior to dispensing same.  
       SUMMARY OF THE INVENTION  
       [0006] Applicant has provided an infrared device for prewarming water prior to dispensing that comprises a cassette having a predetermined length of tubing or a passage corresponding in size to the inside diameter of standard water pipe. The passage has an inlet connectable to a source of water and an outlet connectable to a dispensing tap, such as at a sink, a shower valve, or a bathtub. At least one infrared energy-generating sheet is positioned in the cassette adjacent to the predetermined length of tubing. The infrared energy-generating sheet includes a fiberglass support grid and a matrix layer of a mixture of carbon and polymeric materials formed on the support grid for producing infrared radiation in response to electrical current passed through the matrix layer. A pair of electrical conduction power strips are placed along opposite sides of the matrix layer. Input power terminals are connected to the electrical conduction power strips and an electrical power source is connected to the input power terminals for providing electrical power to be passed through the power strips and thereby pass through the matrix layer of carbon and polymer mixture to generate infrared radiation. The cassette holds the infrared energy-generating sheet adjacent along the predetermined length of tubing so that the infrared energy is transferred to water carried through the tubing.  
       [0007] Preferably, a temperature control microchip is provided operatively connected for sensing the temperature that results from infrared heating of the water and automatically controls the electrical power to the infrared energy-generating sheet to maintain a desired temperature. When hot water from a remote water heater reaches the infrared prewarming unit, the temperature sensor acts to discontiue the power to the infrared heating unit.  
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0008] The foregoing objects, advantages, and features, as well as other objects and advantages, will become more apparent with reference to the description and drawings below, in which like numerals represent like elements and in which:  
     [0009]FIG. 1 schematically depicts an infrared heating layer according to one aspect of the present invention;  
     [0010]FIG. 2 schematically depicts a cassette having a predetermined length of tubing with the infrared heating element positioned therealong, and particularly the length of tubing is shown in a serpentine pattern formed on both sides of a small area of infrared energy-generating sheet, thereby facilitating heat transfer to the tubing;  
     [0011]FIG. 3 shows an alternative embodiment in which a predetermined length of tubing is positioned in a spiral pattern along one side of a heating element passing through a central orifice and spiraling outwardly to an outlet;  
     [0012]FIG. 4 shows a schematic depiction of an assembly view of an infrared heat-generating sheet according to the present invention;  
     [0013]FIG. 5 shows a cross-section view of an infrared heating sheet formed according to assembly view FIG. 4; and  
     [0014]FIG. 6 is a schematic perspective view of an alternative embodiment of a cassette with a serpentine passage therethrough sandwiched between two heat-generating sheets, each having inwardly reflective material laminated on the outside thereof.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0015]FIGS. 2 and 3 show an infrared device  10  for prewarming water  12  that comprises a cassette  14  having a predetermined length  16  of water pipe  18  or a passage  18  corresponding in size to the inside diameter  20  of standard water pipe. The passage  18  has an inlet  22  connectable to a source  12  of water, such as a domestic or industrial hot water heater, and an outlet connectable to a water dispensing device  26  such as a sink hot water tap, a shower hot water valve or a bath tub for prewarmed water for immediate dispensing. At least one infrared energy-generating sheet  30 , as shown in FIGS. 1, 4 and  5 , is positioned in the cassette adjacent to the predetermined length of water pipe  18 . The infrared energy-generating sheet  30  includes a fiberglass support grid  102  and a matrix layer  100  of a mixture of carbon and polymeric materials formed on the support grid for producing infrared radiation in response to electrical current passed through the matrix layer. A pair of electrical conduction power strips  34  and  36  are placed along opposite sides of the matrix layer. Input power terminals  92  are connected to the electrical conduction power strips  34  and  36  and an electrical power source  28  is connected to the input power terminals for providing electrical power to be passed through the power strips and thereby pass through the matrix layer of carbon and polymer mixture to generate infrared radiation. A portable storage battery, preferably less than 24 volts, as for example, 12 volts can be used as the power source  28 . The cassette holds the infrared energy-generating sheet adjacent along the predetermined length of water pipe so that the infrared energy is transferred to water carried through the tubing. Preferably, a temperature control microchip  112  is provided operatively connected for sensing the temperature that results from infrared heating of the water and automatically controls the electrical power to the infrared energy-generating sheet to maintain a desired rate of heating. The matrix layer  100  on support grid  102  may be laminated between high temperature polymeric sheets  42  and  44  bonded together with bonding agent  117 .  
     [0016] Other alterations and modifications of the invention will likewise become apparent to those of ordinary skill in the art upon reading the present disclosure, and it is intended that the scope of the invention disclosed herein be limited only by the broadest interpretation of the appended claims to which the inventors are legally entitled.