Pilotless automatic ignition device

Claim 1

An automatic fluid fuel burner ignition system comprising, under conditions of no heat from said burner: a burner having a spark rod insulatively positioned adjacent said burner to form a spark gap therewith, a main fluid fuel supply conduit to said burner controlled by a pilot or diaphragm actuated valve, and a control fluid fuel supply to actuate said ignition system, means to sense heat from said burner interconnecting with a sensor valve (A) interrupting said control fuel supply and adapted to be normally closed under said condition, means to create a spark across said gap using the flow of said fluid fuel as a motive force, the exhaust of which enters said burner for ignition, time delay valve means operable in the event of accidental burner flame-out to delay passage of fluid fuel to said spark creation means, a spark actuating conduit providing communication of said fluid fuel from upstream of said sensor valve (A) through a normally open pilot valve (D) to said spark creation means, and to a normally closed pilot valve (C) used to control said normally open pilot valve (D), and through a normally open pilot valve (F) to said time delay means; a valve control conduit downstream of said sensor valve (A) providing fluid fuel pressure from said sensor valve, when open, to the pilot of valve F to close same, and reset said time delay means if demanded, and a three-way shuttle valve B open in a first position to communicate with the pilot of valve D to close same, and to the pilot of valve C to open same, and to the pilot of said main gas valve to open same; conduit means from the outlet of valve C to said shuttle valve B in a second position closing said control conduit and communicating with said pilots of valves D and C to maintain same respectively closed and open, and exhaust conduit to said burner from said valves F, C and sensor valve A.