Abstract: The invention relates to a control method for gas burners for providing a gas-air mixture. According to the invention, the ionization signal is only used for setting the mixing ratio dependent on the gas quality when the burner flame completely sweeps over the sensor generating the ionization signal. Outside the above-mentioned range, i.e. when the burner flame does not completely sweep over the sensor generating the ionization signal, the gas-air mixture is controlled dependent on the previously determined mixing ratio.

Abstract: The invention relates to a device for gas burners, comprising at least two air nozzles 10, 11 for combustion air. The air nozzles 10, 11 are arranged in parallel. According to the invention, a flow restrictor 15 is assigned to one or more of the air nozzles 10, 11, respectively. Each of these flow restrictor 15 is capable of selectively shutting off the flow of air through the respective air nozzle 10, 11. This increases the range of modulation of the device according to the invention.

Abstract: A gas control apparatus with a pressure regulator selectively controls the setpoint of the regulator by an electrical current between a minimum and a maximum value of the gas outlet pressure. A diaphragm of the regulator is exposed to the pressure to be controlled and carries a closure member of a bleed valve. A control spring for determining the setpoint of the gas pressure acts between the diaphragm and an adjustable abutment. A solenoid actuator acts between a valve rod of a switch-on valve located between an inlet of the apparatus and the regulator and the abutment. A reset spring for the armature of the actuator acts between a stationary abutment and the armature to engage the armature after the armature has opened the switch-on valve. Thus, the solenoid actuator responds to an electrical current to control the operation of the switch-on valve to provide an inlet pressure for the regulator.

Abstract: A hot water heating system powered by a gas burner uses the output signal of a heat consumption meter measuring the amount of heat flowing to heating radiators for controlling the heat capacity or heating power of the burner. A control signal dependent on the demand of heat is fed to a solenoid operator of a servopressure regulator and the required amount of air for achieving optimum combustion is supplied via an air control valve which receives its input signal from an oxygen or carbon dioxide sensor in a burner stack.

Abstract: A differential pressure responsive switch utilizes an operating diaphragm which has a position controlled by a pressure being monitored with the diaphragm acting through a transmission member upon an electrical switch and includes a first chamber divided by a control diaphragm and having an inlet for the pressure to be monitored to one side of the control diaphragm while the other side of the control diaphragm carries a closure member for an adjacent bleed valve seat. An inlet for the bleed valve is connected via a throttle to a source of a pressurized gas and to a second chamber defined by the operating diaphragm and a spring is engaged through the transmission member to urge the operating diaphragm against the pressure in the second chamber.

Abstract: A control method uses a room thermostat for generating an output signal representative of an energy demand and an energy source which can be cyclically switched on and off and includes the steps of determining within a switching cycle of the energy source the actual switch on period, comparing the actual switch on period with an adjustable desired switch on period within the cycle to produce a control signal representative of the energy demand and controlling the energy source in accordance with the control signal.

Abstract: A safety gas valve with latch against non-permitted reopening has the connector of the thermoelectric power unit located on the same side of the housing as the push button of the operating rod which is born shiftable and turnable in the housing. For this purpose, besides a first lever, carrying the closure member and a latch as part of the latching mechanism and cooperating with the power unit, there is provided a second lever which is tiltable around the stationary axis of the first lever. The one end of the second lever engages the armature pin of the power unit, where the other end is positioned opposite an inclined surface of the latch and disengages the latch from the first lever which carries the closure member. In the normal operating position, a projection of the latch keeps the safety valve open. After closing the valve manually, a portion of the latch is located opposite a stationary abutment until the power unit is deenergized after cooling down the thermocouple.

Abstract: In a control system for a gas heated water or air heater, the use of the supplied fuel gas is to be improved by automatically determining and supplying the amount of air which is required for obtaining complete combustion. A gas control valve feeds a burner with the required amount of gas dependent on the demand of heat. A sensor responding to the content of oxygen or carbon dioxide within the flue gases is located in the stack and the output signal of this sensor is compared with a set point within an electric controller. In case of a control deviation, the output signal of the controller controls an adjustable source of air under pressure formed by a fan with subsequent air control valve in such a manner that the required amount of air for reaching optimum combustion is supplied.

Abstract: An inflatable blood pressure cuff is pressurized with a vapor which is produced by heating a fluid which has a boiling point between 290.degree. K. and 340.degree. K. with an electric heating element. The heating element may comprise a PTC resistor which is disposed within the fluid. A piezoresistive element may also be disposed in the fluid to detect pressure pulses associated with Korotkoff sound.