GB1258029A - - Google Patents

Abstract

1,258,029. Controlling igniters and burners. JOH. VAILLANT K.G. 25 Sept., 1970 [26 Sept., 1969], No. 45703/70. Addition to 1,221,903. Headings F4F and F4T. [Also in Division H2] A piezo-electric ignition device 31 according to claim 1 of the parent Specification is disposed parallel to a rotary gas control comprising coaxial pilot and main valves 2, 3 operable by cams actuated by a rotatable knob 12 carrying gearing 29 meshing with gearing 32 on the rotatable manipulator 50 of the ignition device such that an ignition pulse is produced after opening the pilot valve. To operate the device, knob 12 is first depressed against a spring 14 to engage the gearing 29, 32 after which it is rotated in one direction carrying with it a plate 9 rotatably mounted in the housing 8 of the control. At the same time a cam 10 on the plate 9 rotates a cam support 7 against a return spring 18 causing a plunger 4 to open the pilot valve 2. The igniter produces a pulse to ignite a pilot jet and the knob is held until a thermocouple, heated by the pilot jet, produces sufficient current in an electromagnet 26, Fig. 3, to retain a latch 21 in interlocking engagement with a hook 16 on the cam support 7. Knob 12 is then allowed to retract and disengage the gearing and is rotated in the opposite direction to an intermediate position causing the cam 10 to depress the cam support 7 and open the main valve 3. The knob may be operated to close and open the main valve as often as desired without extinguishing the pilot jet but should it be returned to the initial position, cam 10 depresses support 7 still further and the hook 16 slides off a pin 23 on the latch 21 allowing spring 18 to return the support 7 to its initial position and both valves 2, 3 to close. If the knob 12 is turned towards the "on" position again before the electromagnet has released, the outer edge of hook 16 strikes the pin 23 and prevents the support 7 from rotating to the ignition position and the generation of an ignition pulse.