Multiple actuating device with regulator on the inlet side

摘要

In a multiple actuating device for gas/air combination control of a combustible gas/air mixture in a combustion heat generator according to the servo principle, the regulating valve and the safety valve (8) are each designed as double seat valves, the regulating valve being arranged at the inlet of the gas flow to the multiple actuating device and having a diaphragm plate at the bottom end of the valve stem. The diaphragm plate is provided at the margin with an encircling, sealing control diaphragm (2) and is acted upon at its underside by the control pressure pst and at its top side by a mean pressure pm from a mean-pressure space (7), which is less than or equal to the inlet pressure pe of the inflowing gas stream at the inlet. In this arrangement, the inlet pressure pe of the gas stream can act via a longitudinal bore of the valve stem of the regulating valve on the control-pressure space (4), the top boundary of which forms the underside of the diaphragm plate of the regulating valve, and the control-pressure space (4) can be acted upon on the other side by the burner pressure pbr via a control valve (12) which can be actuated by the first regulating diaphragm (13), to one side of which the burner pressure pbr is applied. Thus less sensitivity of the regulating system to rapid pressure fluctuations from the burner side as well as less dependency of the valve functions on the inlet pressure are achieved. In addition, the energy present in the gas pressure can thereby be optimally utilised for the control pressure. <IMAGE>