GB1092371A - - Google Patents

Abstract

1,092,371. Electric igniters. SPENCER-BONECOURT-CLARKSON Ltd. June 25, 1964 [June 28, 1963], No. 25758/63. Heading F4F. An electric igniter e.g. for oil burners in packaged boilers, comprises an electrode unit 12 which is advanceable against the action of a spring 14 from the retracted position shown wherein the tip 16 of the electrode unit 12 lies within a sheath 18, to an extended position wherein the tip 16 is outside the sheath 18, and a transformer (116), Fig. 4 (not shown), having a high-tension winding which is connected between the electrode unit 12 and earth so that a spark may be initiated between the tip 16 and an earthed electrode 22 when the electrode 12 extends outside the sheath. The electrode 12 is supported in an insulating tube 28 surrounded by a metal tube 24 which is slidable within the sheath 18 in a bearing 36 and a collar 38. An actuator 20 rigidly mounted on the sheath 18 comprises a solenoid 89 which when energized actuates a plunger (88), Fig. 3 (not shown), linked via a lever 96 to a terminal box 56 mounted on the tube 24, so that the box 56 and the electrode 12 are advanced relative to the sheath 18. The electrode 12 may be advanced by hand. When the solenoid 89 is energized, the electrode 12 advances and when fully extended operates a microswitch (118) controlling the spark transformer (116). A timing device (108) controls a switch (106) in the solenoid circuit so that when the switch (106) opens the electrode 12 retracts, and the microswitch (118) is opened to stop the sparking. A high-tension terminal (66), Fig. 2 (not shown), screws on to the electrode 12 and angularly clamps a cone (72) screwed on to the electrode 12, the cone (72) also angularly clamping the insulating tube 28. The earthed electrode 22 is frictionally mounted on the metal tube 24. The electrode 12 and the tubes 24, 28 are relatively angularly adjustable. Apertures 19 in the sheath 18 admit air from an oil burner windbox (not shown) to a passage 39 and holes 40 to cool the electrodes and to prevent sooting thereof. A split bush 50 on the sheath 18 fits into a socket 55 in a boiler wall 54.