Device for manual actuation of a gas distribution valve connected to a burner

#The present invention relates to a device for manual actuation of a gas distribution valve connected to a burner.

#It is well known that gas burners, for instance connected to boilers of a heating system or hot water production, are controlled by gas distribution valves provided with safety devices so that gas delivery is effected only in presence of a flame. For this reason at starting when the flame begins to be produced, gas delivery is ensured by a manual actuation of the valve held in an unstable position and only the direct, manual and voluntary action of the operator allows discharge of gas. A thermocouple sensing the presence of the flame thus reaching a predetermined temperature, allows to pass from the position of valve opening instability to the stable position and subsequently to low, medium and high gas erogation phases. In boilers such as wall boilers for producing hot water or for heating systems, the manual actuation of the gas distribution valve connected to the burner, is easily effected as the boiler is installed in an easily reachable and comfortable position.

#On the contrary actuation of similar devices not used for boilers but for instance for fireplaces as shown in FIG. 1, is not at all easy, where the burner 41 has the gas distribution valve 42 generally close to the burner 41 so that the manual actuation of the valve 42 according to the presently used technique would be really problematic as it is very inconvenient and dangerous.

#Further characteristics and features of the invention will be better understood from the following description of a preferred embodiment given as an illustrative but non limiting example and shown in the accompanying sheets of drawings in which:

#FIG. 1 shows a fireplace provided with the device of the invention;

#FIG. 2 shows a gas distribution valve with a partial view of the device of the invention;

#With reference to the mentioned FIGS. of the drawings and more particularly to FIG. 3, one can see that the gas distribution valve generally indicated with numeral 100, has a gas inlet duct 1 with a gas interception means or plug 10 which is controlled by the rod 51 belonging to a stem 5. The interception means 10 is also connected to the solenoid valve 101 that holds the plug 10 open as explained below, when the enabling signal arrives from the thermocouple not shown in the drawing, detecting the presence of flame in the burner. Downstream the plug 10 there are two gas delivery ducts 2 and 3 receiving gas when the plug 10 is open. In the position shown in FIG. 3, a second plug 8 does not allow gas to flow into the chamber 11 thus reaching the regulator 9 and consequently the other gas delivery duct 4. The valve as shown in FIG. 3, that is with the plug 10 open and the second plug 8 in the illustrated position 81 corresponding to FIG. 5, corresponds to the unstable position of arming the solenoid valve 101 when starting the burner 41 is initiated, as well as to the stable position reached when the thermocouple not shown in the drawing enables the solenoid valve 101 to hold the plug 10 open even in absence of manual pressure pushing the rod 51 in the direction of keeping the plug 10 open.

#According to the invention the rod 51 is held in the position shown in FIG. 3 by a flexible metal wire 14 having an end 141 fixed to a block 17 connected to the end of stem 5 and fastened by a screw 16, and at the other end 142 fixed to a control lever 20 that can rotate parallel to the support plane 30 on the pin 31 so as to take various positions as shown in FIG. 3.

#More particularly the lever 20 when the burner is started and therefore when the pilot flame starts, takes the position corresponding to the notch 21 which is an unstable position. Indeed were the lever 20 released from the manual action, the plug 10 would close gas delivery and lever 20 would go to the position defined by notch 22. This would happen because the wire 14 is returned to such position by spring 13 acting on the stem 5 in the direction of extending it out from valve 100 and stops on the first notch 22 on the plate 30, that can be seen also in FIG. 4. At position 22, lever 20 remains stable in its position provided that the solenoid 101 is energized by closure of the thermocouple detecting the presence of flame.