Combustion membrane for a gas burner

Abstract

A combustion membrane ( 14 ) for a gas burner ( 2 ) comprises a fabric ( 21 ) having two opposite fabric surfaces ( 19, 20 ) which form a combustion surface ( 19 ) exposed on the outer side ( 17 ) and an inner surface ( 20 ) facing an inner side ( 18 ), respectively, wherein the fabric ( 21 ) forms an interlacement of metal threads ( 22 ) comprising warp threads and weft threads transverse with respect to the warp threads, wherein: both fabric surfaces ( 19, 20 ) form high-relief ribs ( 23 ) formed by a main float thread ( 25 ), respectively, extending straddling exactly three underlying transverse threads, and wherein a side thread bridge ( 25 ′), extending straddling exactly one underlying transverse thread, is formed on both longitudinal sides of each main float thread ( 25 ), so that the main float thread ( 25 ) and the two side thread bridges ( 25 ′) delimit a cross thread configuration ( 25 ″) formed by mutually parallel threads.

1 . A combustion membrane ( 14 ) for a gas burner ( 2 ), said combustion membrane ( 14 ) having an inner side ( 18 ) to which a combustible gas ( 13 ) is conveyed and an outer side ( 17 ) on which combustion of the combustible gas ( 13 ) occurs after it has crossed the combustion membrane ( 14 ), said combustion membrane ( 14 ) comprising a fabric ( 21 ) having two opposite fabric surfaces ( 19 ,  20 ) which form a combustion surface ( 19 ) exposed on the outer side ( 17 ) and an inner surface ( 20 ) facing the inner side ( 18 ), respectively, wherein the fabric ( 21 ) forms an interlacement of metal threads ( 22 ) comprising warp threads and weft threads transverse with respect to the warp threads,
 wherein both fabric surfaces ( 19 ,  20 ) form high-relief ribs ( 23 ) alternating with low-relief sags ( 24 ),   characterized in that:
 the ribs ( 23 ) are formed by a main float thread ( 25 ), respectively, extending straddling exactly three underlying transverse threads, and 
 a side thread bridge ( 25 ′), extending straddling exactly one underlying transverse thread, is formed on both longitudinal sides of each main float thread ( 25 ), directly adjacent and parallel thereto and located centrally with respect to the longitudinal extension thereof, 
   so that the main float thread ( 25 ) and the two side thread bridges ( 25 ′) delimit a cross thread configuration ( 25 ″) formed by mutually parallel threads.   
     
     
         2 . A combustion membrane ( 14 ) according to  claim 1 , wherein in the same cross thread configuration ( 25 ″), the side thread bridges ( 25 ″) are retracted with respect to the main float thread ( 25 ) which protrudes from the fabric ( 21 ). 
     
     
         3 . A combustion membrane ( 14 ) according to  claim 1 or 2 , wherein on the combustion surface ( 19 ) and on the inner surface ( 20 ), said cross thread configurations ( 25 ″) are formed with both weft metal threads ( 22 ) and warp metal threads ( 22 ). 
     
     
         4 . A combustion membrane ( 14 ) according to  any one of the preceding claims , wherein:
 A) a first plurality of the cross thread configurations ( 25 ″) formed by warp threads is arranged grouped into first groups ( 25 . 1 ) of exactly two cross thread configurations ( 25 ″) directly adjacent and aligned in a first diagonal direction ( 28 . 1 ) with respect to the weft ( 30 ) and warp ( 31 ) directions of the fabric ( 21 ),   wherein between two said first groups ( 25 . 1 ) of cross configurations ( 25 ″) aligned along said first diagonal direction ( 28 . 1 ), respectively, a first diagonal distance ( 26 . 1 ) is formed without cross configurations ( 25 ″) aligned along the same first diagonal direction ( 28 . 1 ),   wherein said first diagonal distance ( 26 . 1 ) is equal to a first diagonal extension ( 27 . 1 ) of the first group ( 25 . 1 ) of cross thread configurations ( 25 ″),   B) a second plurality of the cross thread configurations ( 25 ″) formed by warp threads is arranged grouped into second groups ( 25 . 2 ) of exactly two cross thread configurations ( 25 ″) directly adjacent and aligned in a second diagonal direction ( 28 . 2 ) with respect to the weft ( 30 ) and warp ( 31 ) directions of the fabric ( 21 ), transverse to the first diagonal direction ( 28 . 1 ),   wherein between two said second groups ( 25 . 2 ) of cross configurations ( 25 ″) aligned along said second diagonal direction ( 28 . 2 ), respectively, a second diagonal distance ( 26 . 2 ) is formed without cross configurations ( 25 ″) aligned along the same second diagonal direction ( 28 . 2 ),   wherein said second diagonal distance ( 26 . 2 ) is equal to a second diagonal extension ( 27 . 2 ) of the second group ( 25 . 2 ) of cross thread configurations ( 25 ″),   C) a third plurality of the cross thread configurations ( 25 ″) formed by weft threads is arranged grouped into third groups ( 25 . 3 ) of exactly two cross thread configurations ( 25 ″) directly adjacent and aligned in a third diagonal direction ( 28 . 3 ) with respect to the weft ( 30 ) and warp ( 31 ) directions of the fabric ( 21 ),   wherein between two said third groups ( 25 . 3 ) of cross configurations ( 25 ″) aligned along one said third diagonal direction ( 28 . 3 ), respectively, a third diagonal distance ( 26 . 3 ) is formed without cross configurations ( 25 ″) aligned along the same third diagonal direction ( 28 . 3 ),   wherein said third diagonal distance ( 26 . 3 ) is equal to a third diagonal extension ( 27 . 3 ) of the third group ( 25 . 3 ) of cross thread configurations ( 25 ″),   D) a fourth plurality of the cross thread configurations ( 25 ″) formed by weft threads is arranged grouped into fourth groups ( 25 . 4 ) of exactly two cross thread configurations ( 25 ″) directly adjacent and aligned in a fourth diagonal direction ( 28 . 4 ) with respect to the weft ( 30 ) and warp ( 31 ) directions of the fabric ( 21 ), transverse to the third diagonal direction ( 28 . 3 ),   wherein between two said fourth groups ( 25 . 4 ) of cross configurations ( 25 ″) aligned along said fourth diagonal direction ( 28 . 4 ), respectively, a fourth diagonal distance ( 26 . 4 ) is formed without cross configurations ( 25 ″) aligned along the same fourth diagonal direction ( 28 . 4 ),   wherein said fourth diagonal distance ( 26 . 4 ) is equal to a fourth diagonal extension ( 27 . 4 ) of the fourth group ( 25 . 4 ) of cross thread configurations ( 25 ″).   
     
     
         5 . A combustion membrane ( 14 ) according to  claim 4 , wherein a first orthogonal distance ( 29 . 1 ) between two said first neighboring diagonal directions ( 28 . 1 ), respectively, along which the first groups ( 25 . 1 ) of cross thread configurations ( 25 ″) are arranged, is constant and equal to the first diagonal distance ( 26 . 1 ). 
     
     
         6 . A combustion membrane ( 14 ) according to  claim 4 or 5 , wherein a second orthogonal distance ( 29 . 2 ) between two said second neighboring diagonal directions ( 28 . 2 ), respectively, along which the second groups ( 25 . 2 ) of cross thread configurations ( 25 ″) are arranged, is constant and equal to the second diagonal distance ( 26 . 2 ). 
     
     
         7 . A combustion membrane ( 14 ) according to  claim 4 or 5 or 6 , wherein a third orthogonal distance ( 29 . 3 ) between two said third neighboring diagonal directions ( 28 . 3 ), respectively, along which the third groups ( 25 . 3 ) of cross thread configurations ( 25 ″) are arranged, is constant and equal to the third diagonal distance ( 26 . 3 ). 
     
     
         8 . A combustion membrane ( 14 ) according to any one of  claims 4 to 7 , wherein a fourth orthogonal distance ( 29 . 4 ) between two said fourth neighboring diagonal directions ( 28 . 4 ), respectively, along which the fourth groups ( 25 . 4 ) of cross thread configurations ( 25 ″) are arranged, is constant and equal to the fourth diagonal distance ( 26 . 4 ). 
     
     
         9 . A combustion membrane ( 14 ) according to any one of  claims 4 to 8 , wherein the first ( 26 . 1 ), second ( 26 . 2 ), third ( 26 . 3 ), and fourth ( 26 . 4 ) diagonal distances are equal and constant. 
     
     
         10 . A combustion membrane ( 14 ) according to any one of  claims 4 to 9 , wherein a fifth smaller orthogonal distance ( 29 . 1 - 3 ) between one of the first diagonal directions ( 28 . 1 ), along which the first groups ( 25 . 1 ) of cross thread configurations ( 25 ″) are arranged, and one of the third diagonal directions ( 28 . 3 ), along which the third groups ( 25 . 3 ) of cross thread configurations ( 25 ″) are arranged, is less than half the first orthogonal distance ( 29 . 1 ) and less than half the third orthogonal distance ( 29 . 3 ). 
     
     
         11 . A combustion membrane ( 14 ) according to any one of  claims 4 to 10 , wherein a sixth smaller orthogonal distance ( 29 . 2 - 4 ) between one of the second diagonal directions ( 28 . 2 ), along which the second groups ( 25 . 2 ) of cross thread configurations ( 25 ″) are arranged, and one of the fourth diagonal directions ( 28 . 4 ), along which the fourth groups ( 25 . 4 ) of cross thread configurations ( 25 ″) are arranged, is less than half the second orthogonal distance ( 29 . 2 ) and less than half the fourth orthogonal distance ( 29 . 4 ). 
     
     
         12 . A combustion membrane ( 14 ) according to any one of  claims 4 to 11 , wherein the first diagonal directions ( 28 . 1 ) and third diagonal directions ( 28 . 3 ) are parallel to one another, and the second diagonal directions ( 28 . 2 ) and fourth diagonal directions ( 28 . 4 ) are parallel to one another. 
     
     
         13 . A combustion membrane ( 14 ) according to any one of  claims 4 to 12 , wherein both cross thread configurations ( 25 ″) of each first group ( 25 . 1 ) are directly bordering to both cross thread configurations ( 25 ″) of a respective third group ( 25 . 3 ), except for the edges of the fabric ( 21 ). 
     
     
         14 . A combustion membrane ( 14 ) according to any one of  claims 4 to 13 , wherein both cross thread configurations ( 25 ″) of each second group ( 25 . 2 ) are directly bordering to both cross thread configurations ( 25 ″) of a respective fourth group ( 25 . 3 ), except for the edges of the fabric ( 21 ). 
     
     
         15 . A combustion membrane ( 14 ) according to  any one of the preceding claims , wherein the combustion surface ( 19 ) and the inner surface ( 20 ) both have the same weave structure, mutually turned by 90°. 
     
     
         16 . A combustion membrane ( 14 ) according to  any one of the preceding claims , wherein the fabric ( 21 ) is formed by a repetition in the weft direction ( 30 ) and in the warp direction ( 31 ) of a same 8-by-8 base weaving pattern:
 T,O,T,O,T,O,T,T   O,T,O,O,O,T,O,T   T,O,T,O,T,T,T,O   O,T,O,T,O,T,O,O   T,T,T,O,T,O,T,O   O,T,O,T,O,O,O,T   T,O,T,T,T,O,T,O   O,O,O,T,O,T,O,T,   wherein, viewed from one side of the fabric ( 21 ), the emerging and visible weft threads are indicated by T and the emerging and visible warp threads are indicated by O.   
     
     
         17 . A combustion membrane ( 14 ) according to  any one of the preceding claims , wherein the fabric ( 21 ) is supported by and in contact with a support layer ( 32 ) arranged on the inner side ( 18 ) of the combustion membrane ( 14 ). 
     
     
         18 . A combustion membrane ( 14 ) according to  any one of the preceding claims , wherein the fabric ( 21 ) has a weight by extension area in the range from 1.1 kg/m 2  to 1.3 kg/m 2 , or of 1.20 kg/m 2 . 
     
     
         19 . A gas burner ( 2 ) comprising a combustion membrane ( 14 ) according to  any one of the preceding claims .