Abstract: The system for active regulation of the air/gas ratio of a burner comprises one or two differential pressure measuring systems each of which has a differential pressure sensor with two inlet orifices. The orifices are respectively connected to pressure ports in one of which there is a calibrated throttling orifice. The regulator system comprises a 2-channel valve which, when closed, isolates the two inlet orifices from each other, and, when open, connects them to each other. A measurement circuit is provided and has memory means for storing at least two values of the output signal of the sensors, a control unit for switching the valve and controlling the storage of a first value of an output signal of the sensor in the memory means when the valve is closed and the storage of a second value of the output signal of the sensor when the valve is open, and subtractor means for calculating the difference between the two stored values of the output signal of the sensor and thereby eliminating any drift.

Abstract: A pressure sensor operates on the principle of a differential pair of capacitors having a movable plate that is constituted by the deformable membrane of the sensor. It comprises a measurement circuit for measuring the capacitance of the capacitor, which circuit is incorporated in the housing of the sensor and is made up of first and second double-sided interconnected circuits which are situated on either side of the membrane and which are connected thereto in its peripheral region by connection means.

Abstract: A valve including a cylindrical bore having a circular seat at one end thereof, a valve member that is movable in the axial direction of the seat, and control means connected to the valve member, the valve member including a first portion which serves as a closure element, and a second portion which is engaged in the bore and which is shaped to regulate the flow of the fluid at a desired rate depending on the axial position of the valve member, the second portion of the valve member is detached from the first portion and has a cylindrical outside surface of diameter such that it is in sliding contact with the cylindrical surface of the bore; at least one recess is formed in the cylindrical outside surface of the second portion of the valve member so as to define a passage having a predefined shape, and means is provided for permanently holding the two portions of the valve member in mutual contact so that they are displaced axially simultaneously under the action of the control means.