Localized heating techniques incorporating tunable infrared element(s) for vacuum insulating glass units, and/or apparatuses for same

Abstract

Certain example embodiments of this invention relate to edge sealing techniques for vacuum insulating glass (VIG) units. More particularly, certain example embodiments relate to techniques for providing localized heating to edge seals of units, and/or unitized ovens for accomplishing the same. In certain example embodiments, infrared (IR) heating elements are controllable to emit IR radiation at a peak wavelength in the near infrared (NIR) and/or short wave infrared (SWIR) band(s), and the peak wavelength may be varied by adjusting the voltage applied to the IR heating elements. The peak wavelength may be selected so as to preferentially heat the frit material used to form a VIG edge seal while reducing the amount of heat provided to substrates of the VIG unit. In certain example embodiments, the substrates of the VIG unit do not reach a temperature of 325 degrees C. for more than 1 minute.

1 . An apparatus for forming an edge seal in a vacuum insulated glass (VIG) unit, comprising:
 a plurality of infrared (IR) heating elements controllable to emit IR radiation at a peak wavelength in the near infrared (NIR) and/or short wave infrared (SWIR) band(s),   the plurality of IR heating elements being spaced apart from one another so as to have a 2-6″ center-to-center distance,   the plurality of IR heating elements being vertically positioned 2-10″ above an upper surface and/or below a lower surface of a VIG subassembly insertable therein;   a controller operable to adjust an amount of voltage supplied to the plurality of IR heating elements to vary the peak wavelength produced by the plurality of IR heating elements;   inner walls comprising a material having characteristics suitable for causing a reduced amount of IR radiation from the IR heating elements impinging thereon to be reflected, the reflected IR radiation being reflected in a generally diffuse or undirected pattern; and   insulation provided around the inner walls.   
     
     
         2 . The apparatus of  claim 1 , wherein the peak wavelength is between 1300-1700 nm. 
     
     
         3 . The apparatus of  claim 1 , wherein the peak wavelength is selected so that at least about three times as much energy is absorbable by a frit material of the VIG subassembly as compared to glass substrates of the VIG subassembly. 
     
     
         4 . The apparatus of  claim 1 , wherein the position of the plurality of IR heating elements is vertically adjustable. 
     
     
         5 . The apparatus of  claim 1 , further comprising one or more jack screws for adjusting the vertical position of the plurality of IR heating elements, collectively or individually, relative to the upper surface of the VIG subassembly. 
     
     
         6 . The apparatus of  claim 1 , wherein the IR heating elements are oriented at approximately 90 degree angles relative to a surface on which they are mounted. 
     
     
         7 . The apparatus of  claim 1 , wherein the IR heating elements are oriented at approximately 45 degree angles relative to a surface on which they are mounted. 
     
     
         8 . The apparatus of  claim 1 , wherein the IR heating elements are operable to maintain a stable heating environment in which the temperature across the VIG subassembly would vary by no more than ±5 degrees C. 
     
     
         9 . The apparatus of  claim 1 , wherein the IR heating elements are operable to maintain a stable heating environment in which the temperature across the VIG subassembly would vary by no more than ±2 degrees C. 
     
     
         10 . The apparatus of  claim 1 , wherein the inner walls comprise a hardened batt material. 
     
     
         11 . The apparatus of  claim 1 , wherein the IR heating elements are operable to maintain an interior thereof at a first elevated temperature without the use of any further heating elements, the first elevated temperature being lower than a temperature needed to form the edge seal. 
     
     
         12 . The apparatus of  claim 11 , wherein the IR heating elements are controllable via voltage changes to move from the first elevated temperature to the temperature needed to form the edge seal. 
     
     
         13 - 23 . (canceled) 
     
     
         24 . An apparatus for forming an edge seal in a vacuum insulated glass (VIG) unit, comprising:
 a plurality of infrared (IR) heating elements controllable to emit IR radiation at a peak wavelength in the near infrared (NIR) and/or short wave infrared (SWIR) band(s),   a controller operable to adjust an amount of voltage supplied to the plurality of IR heating elements to vary the peak wavelength produced by the plurality of IR heating elements;   wherein the controller is operable in first and second modes, the first mode being a preheat mode at which the IR heating elements operate at approximately half power density and 45-55% voltage and the second mode being a frit sealing mode at which the IR heating elements operate at a half power density and at 75-85% voltage.   
     
     
         25 . (canceled)