Device for controlling the supply of a combustible gas to a burner of a heating apparatus

A device for controlling the supply of a combustible gas to a burner of a heating apparatus, the device comprising:

• a pipe (2) for supplying the gas which extends between an inlet section (3) and an outlet section (4),
• at least one valve (6) including a respective valve seat (6a) which is associated with a corresponding closure member (6b) which is provided with a respective control rod (7) for opening the valve seat counter to a resilient return means (8),
• a system for amplifying the movement of the control rod (7) of the closure member, the system comprising a snap-fit spring (26) which acts on the rod (7) and a pushing element (27) which in turn acts on the snap-fit spring (26) in order to activate a snap-fit movement of the spring,
• the pushing element (27) being acted upon by a first end (28a) of a lever (28), which is hinged at a fulcrum location which is positioned at an opposing second end (28b) of the lever,
• an actuator operationally associated with the lever in a position between the opposing ends (28a, 28b) for control of the lever during a pivoting movement about the fulcrum location for a resultant movement of the closure member (6b) away from and towards the valve seat (6a) by the amplification system, the actuator comprising a linear actuator element (30) with a converse piezoelectric effect, in which a linear movement of the actuator is proportionally correlated with a signal of an electric control voltage which is applied to the actuator;
• and
• a sensor (35) configured to detect temperature and an electronic control unit (33) of the device, to which a signal detected by the sensor (35) is transmitted, the electronic control unit further comprising a comparator, which compares the temperature signal detected with a preselected and selectable temperature level in the control unit (33), and a control signal generator of the piezoelectric actuator (30) in order to open/close the at least one valve (6) in order to reach the selected temperature level.