Injection nozzle and combustion device

Abstract

An injection nozzle includes: an inner wall having a cylindrical shape; a first outer wall having a cylindrical shape and being formed integrally with the inner wall through intermediation of a connection portion; a fuel passage having an annular shape and being formed between the inner wall and the first outer wall; and an inner air passage formed on an inner side of the inner wall.

What is claimed is: 
     
         1 . An injection nozzle, comprising:
 an inner wall having a cylindrical shape;   an outer wall having a cylindrical shape and being formed integrally with the inner wall through intermediation of a connection portion;   a fuel passage having an annular shape and being formed between the inner wall and the outer wall; and   an inner air passage formed on an inner side of the inner wall.   
     
     
         2 . The injection nozzle according to  claim 1 , further comprising a swirling portion that is formed integrally with at least one of the inner wall and the outer wall and arranged in the fuel passage obliquely to a circumferential direction of the inner wall and the outer wall. 
     
     
         3 . The injection nozzle according to  claim 1 , further comprising a swirling blade that is formed integrally with the inner wall and arranged in the inner air passage obliquely to a circumferential direction of the inner wall. 
     
     
         4 . The injection nozzle according to  claim 3 , further comprising:
 a shaft portion arranged on a center axis of the inner air passage and formed integrally with the swirling blade;   a distribution portion formed inside the shaft portion; and   a fuel communication passage formed inside the swirling blade and allowing communication between the distribution portion and the fuel passage.   
     
     
         5 . The injection nozzle according to  claim 1 , further comprising:
 an air supply passage connected to the inner air passage and extending tangentially to the inner air passage; and   a fuel communication passage that is formed so as to separate from the air supply passage in a circumferential direction, and communicates with the fuel passage.   
     
     
         6 . A combustion device, comprising the injection nozzle of  claim 1 .