Solar collector

Abstract

A solar collector, includes a glass sheet provided with a fired metal frit; a metal frame or another glass sheet provided with a fired metal frit and a metal frame; a brazed seal between the metal frit or frits and the metal frame; an absorber and pipes in which a heat-transfer fluid circulates, the pipes being in contact with the absorber, and the absorber and the pipes being placed between the glass sheet and the metal frame or between the two glass sheets. The invention provides a solar collector which is compact and simple and improves solar radiation transmission.

1 . A solar collector, comprising:
 a glass sheet provided with a fired metal frit;   a metal frame or another glass sheet provided with a fired metal frit and a metal frame;   a brazed seal between the metal frit or frits and the metal frame;   an absorber and pipes in which a heat-transfer fluid circulates, the pipes being in contact with the absorber, and the absorber and the pipes being placed between the glass sheet and the metal frame or between the two glass sheets.   
     
     
         2 . The solar collector as claimed in  claim 1 , comprising a single glass sheet and a metal frame, the metal frame being provided with a bottom and a free edge of the metal frame being brazed to the metal frit of the glass sheet. 
     
     
         3 . The solar collector as claimed in  claim 1 , comprising two glass sheets and a metal frame, the edges of the metal frame being brazed to the metal frits of each of the two glass sheets. 
     
     
         4 . The solar collector as claimed in  claim 1 , wherein the metal frame comprises a wall offset with respect to the brazed seal and/or a wall connected to the brazed seal by a low thermal conductivity material. 
     
     
         5 . The solar collector as claimed in  claim 1 , wherein the glass sheet is, or the glass sheet and the other glass sheet are, tempered. 
     
     
         6 . The solar collector as claimed in  claim 1 , wherein a brazing alloy of the brazed seal has a melting point between 100° C. and 350° C. 
     
     
         7 . The solar collector as claimed in  claim 6 , wherein the brazing alloy is the alloy Pb 93.5 Sn 5 Ag 1.5 . 
     
     
         8 . The solar collector as claimed in  claim 1 , wherein the fired metal frit comprises between 50% and 95% by weight of silver particles, the rest being a vitreous binder comprising SiO 2 , Bi 2 O 3 , Na 2 O and ZnO. 
     
     
         9 . The solar collector as claimed in  claim 1 , the solar collector being under a vacuum. 
     
     
         10 . The solar collector as claimed in  claim 1 , wherein the glass sheet is made of extra-clear glass. 
     
     
         11 . The solar collector as claimed in  claim 1 , wherein the glass sheet is provided with an antireflection coating. 
     
     
         12 . The solar collector as claimed in  claim 1 , wherein each glass sheet is joined to an additional glass sheet via a polymeric interlayer in order to form a laminated glazing unit.