| 摘要 |
A thermostat for gas-powered cooking appliances includes a body having an inlet conduit and an outlet conduit that respectively receive and supply a gas flow, and a chamber in fluid communication both with the inlet conduit, and also with the outlet conduit either directly, through a main opening formed at one end thereof, or indirectly, through a secondary conduit formed in the body of the thermostat, which reaches the outlet conduit bypassing the main opening. A valve that adjusts gas flow rate is coaxially fitted in the chamber and has a position that is controlled by an expandable member of a thermostatic bulb of the thermostat. The valve is axially deformable beyond a predefined load threshold and compensates for dilations of the expandable member under a normal operating condition, absorbing axial forces exerted by the thermostat knob when rotated to switch off a burner driven by the thermostat. |
| 主权项 |
1. A thermostat (10) for cooking appliances supplied by gas, said thermostat (10) comprising:
a body (20) within which there are formed,
an inlet duct (23) and an outlet duct (24), respectively configured to receive a gas flow from a supply source and to supply the gas flow to a gas burner, anda chamber (25) of a cylindrical shape disposed in fluid communication with said inlet duct (23), wherein said chamber (25) is also disposed in fluid communication with said outlet duct (24) either directly, through a main opening (70) formed at one end thereof, or indirectly, through a secondary duct (71) formed in the body (20) of the thermostat (10) and flowing into the outlet duct (24) bypassing said main opening (70), said main opening and secondary duct (70, 71) being respectively dimensioned for a maximum and a minimum flow rates of gas; a valve (80) arranged in the chamber (25) and configured to regulate flow rate of the gas, wherein the valve (80) is movable coaxially to the chamber (25) in a first direction (A) of the body (20) between a first, maximum opening position, wherein the main opening (70) is completely clear thus allowing passage of the gas flow towards the outlet duct (24), and a second, closing position, wherein the main opening (70) is completely closed by the valve (80) and the gas flow reaches the outlet duct (24) through the secondary duct (71) only, the valve (80) being urged in said first, opening position by a helical spring fitted in the chamber (25) at the main opening (70); and a thermostatic bulb (50) with an expandable member (53), the position of the valve being controlled by the expandable member (53) of the thermostatic bulb (50) of the thermostat (10), the expandable member (53) contacting the valve (80) at an end opposite to an end on which the helical spring acts, wherein the valve (80) is configured to be axially deformable beyond a predefined load threshold, said load threshold being higher than a maximum reaction force that the helical spring urging the valve (80) towards the first, opening position exerts when the valve (80) is in the second, closing position. |
