Air-fuel spray nozzle

Claim 1

A spray nozzle for mixing fuel and air therein, said nozzle comprising: a cylindrical housing having an inner chamber on the axis thereof, a plurality of circumferentially spaced helical vanes radially extending outwardly from said housing, said vanes extending over essentially the entire length of said housing, said chamber having a fuel inlet and a plurality of fuel outlets, each of said fuel outlets extending radially through said housing into the spaces between said vanes; a cylindrical wall mounted coaxially with said cylindrical housing, said wall being spaced from said housing by said vanes, said vanes contacting said housing throughout the entire length of said vaNes to provide a plurality of helical passages, each of said fuel outlets communicating with a respective passage, said housing having an air inlet at one end and an outlet at the other end, the outlet end of said cylindrical wall being formed with a radially inwardly projecting lip; means supplying fuel to said chamber under pressure, whereby all of said fuel flows radially into said helical passages; and means for flowing air through said helical passages whereby all of said fuel supplied to said chamber is mixed with air moving through said passages, and mixed fuel and air exits from said outlet.