| 摘要 |
1,115,999. Controlling gas burners. ROBERTSHAW CONTROLS CO. 1 Dec., 1965 [2 Dec., 1964], No. 51061/65. Headings F4F and F4T. An oven burner 51, Fig. 8 is ignited by a pilot burner 10, the flame of which is enlarged at ignition to provide both an igniting flame and a heating flame, the latter heating a temperature sensing bulb 47 adapted to open a safety valve 58 supplying the oven burner. A flame shield 13, Fig. 2, associated with the pilot burner comprises a first portion 28 having an opening 29 through which the igniting flame issues and a second slotted portion 32 which directs part of the enlarged flame downwardly towards a pair of spaced ears 40, 41 formed on the end of the second portion and adapted to support the sensing bulb 47. The pilot burner comprises a bent conduit 15 brazed to a hexagonal retainer 17 having a threaded inlet for connection to a fuel line and having a transverse opening 19 through which air is drawn. In a modification. Figs. 10-14 (not shown), the pilot burner directs the Mixture upwardly on to an inclined apertured first part of the shield and the second slotted part is disposed horizontally. The safety valve 58, Fig. 7 (not shown), comprises an expansible element (65) connected by a conduit (49) to the temperature sensing element 47 and to a valve member (63) through a snap action lever and spring device (64). The fuel supply to the oven and pilot burners is controlled by a device 52, Fig. 8, comprising a valve 57 opened by a knob 56 to connect a fuel manifold 54 to a chamber 55 and to a chamber 77. The pilot burner is supplied continuously by to passage 74 to provide small standby flame and the enlarged pilot flame is produced by an additional of fuel to the pilot burner by the opening of a ball valve 79 between the chamber 77, and a third chamber 76. The ball valve 79 is opened by a lever 81 fulcrumed on the end 83 of an axially movable pin 84 connected to the knob 56. The end of the lever remote from the ball valve is connected to an expansible element 87 connected to a second temperature sensing element 88 in the oven. When the oven temperature is below the temperature set by the knob 56, the ball valve opens and the enlarged pilot flame actuates the safety valve 58 and fuel flows from the chamber 55 to the oven burner. |
