The present invention relates to a new gas cock.
Cocks at present on the market consist of a plug or taper-stemmed obturator with several holes or orifices in its body and a main shell in which the aforesaid plug is accurately fitted.
This plug is thrust by a spring which tends to insert it in the main shell housing or valve body in order to absorb wear which might be caused with use.
The details mentioned are lubricated with a special grease which also seals the plug with the shell.
The cocks in question had the following faults:
In the event of loss of grease, leaks develop due to lack of tightness and microweld faults, the cock eventually becoming useless.
As a consequence of the fit and temperature, the cone seizes when hot, preventing operation to select burners or intakes.
Together with friction, another consequence of fit is the need for a low-friction factor material, at present the practice is to use brass or bronze, which are expensive materials, significantly increasing production cost.
Similarly increasing production cost is the extreme machining accuracy of the plug and socket needed to ensure tightness.