Method of operating a gas-infrared radiator, and the gas-infrared radiator

Abstract

In order to adapt a gas-infrared radiator (a radiant burner) to operating conditions in a particularly efficient manner, the energy delivered is reduced by intermittently reducing a controlled supply of gas so that the energy delivery is below about 40% or even less of the maximum energy delivery of the infrared radiator, and a flame supplied separately from the controlled gas supply is maintained in the combustion chamber of the gas-infrared radiator, at least when operating in the aforementioned range. This is achieved more particularly by providing at least one nozzle (22) for a pilot light, directed towards the combustion chamber (4).

What is claimed: 
     
       1. A method of operating a gas infrared radiator with variable energy output and comprising means forming a combustion chamber surrounded substantially on all sides by components and a pre-chamber adjacent the combustion chamber, a barrier layer of fibrous material with a plurality of pipes extending therethrough separating the pre-chamber from the combustion chamber, the amount of gas other than air supplied to the combustion chamber or said pre-chamber .[.chamber.]. being variable by a control device, characterized in that the amount of gas supplied is intermittently varied by a pulse control system down to a range corresponding to an energy .[.delivery.]. .Iadd.level .Iaddend.less than about 40% of the maximum rated energy obtainable from the infrared radiator, the air supply being continuously maintained, and a flame supplied with gas is maintained in the combustion chamber separately from the controlled gas supply when operating in the previously-mentioned range. 
     
     
       2. A method according to claim 1, characterized in that said gas other than air is intermittently reduced to a range less than about 20% of said maximum rated energy. 
     
     
       3. A method according to claim 2, characterised in that the controlled gas supply is intermittently reduced to a range corresponding to practically zero energy delivery by the infrared radiator. 
     
     
       4. A method according to any of claims 1 to 3, characterised in that the flame separately supplied with gas is also separately supplied with combustion air. 
     
     
       5. A gas infrared radiator comprising a pre-chamber connected to gas and air supply pipes and a combustion chamber surrounded substantially on all sides by components, a plurality of individual pipes for supplying a gas-air mixture and extending between the pre-chamber and the combustion chamber through a heat-resistant gas permeable barrier layer, pulse control means for intermittently varying the supply of fuel gas, at least one nozzle for a pilot light directed into the combustion chamber, and means providing a separate gas supply to said nozzle independent of the means for varying the supply of fuel gas. 
     
     
       6. A radiator according to claim 5, characterized in that the nozzle is surrounded by means forming a flow path for air or an air-containing medium. 
     
     
       7. A radiator according to claim 6 wherein said prechamber is supplied with .[.a.]. .Iadd.said .Iaddend.gas-air mixture from a mixing-chamber and separated from the combustion chamber by the aforementioned heat-resistant barrier layer, characterised in that the flow path is a duct extending throughout the barrier layer. 
     
     
       8. A gas infrared radiator, comprising: .Iadd.a .Iaddend.pre-chamber connectable to gas and air supply pipes;   a combustion chamber surrounded substantially on all sides by components;   a heat resistant, gas permeable barrier layer disposed between the pre-chamber and said combustion chamber;   a plurality of individual conduits for supplying a gas and air mixture from the pre-chamber into the combustion chamber through said heat resistant barrier layer;   pulse control means for supplying and intermittently varying the supply of fuel gas to said pre-chamber;   at least one nozzle for a pilot light directed into the combustion chamber through said barrier layer, said nozzle being surrounded by means forming a flow path of said mixture into said combustion chamber; and   means providing a separate gas supply to said nozzle independently of the means for varying the supply of fuel gas. .Iadd.   
     
     
       9.  A method of operating a gas infrared radiator to provide a variable energy output and comprising means forming a combustion chamber and pre-chamber, a barrier layer arranged between said pre-chamber and said combustion chamber, said barrier layer having a plurality of pipes extending through said barrier layer for communicating said pre-chamber with said combustion chamber, the amount of a gas other than air supplied to the combustion chamber or said pre-chamber being variable by a control device, characterized in that the amount of gas supplied is intermittently varied by a pulse control system to regulate the output energy of the infrared radiator over a range extending from the maximum rated energy level capable of being delivered by the infrared radiator to an energy level less than about 40% of said maximum rated energy level, the air supply to said mixing chamber being continuously maintained and a pilot flame in said combustion chamber being maintained by gas supplied to the combustion chamber separately from the controlled gas supply to assure combustion within said combustion chamber whenever gas is delivered to the combustion chamber from said pre-chamber. .Iaddend. .Iadd.10. The method of claim 9 being further characterized in that said gas other than air is intermittently varied so that the energy level at the lower end of the range is less than about 20% of said maximum rated energy. .Iaddend. .Iadd.11. The method of claim 9 being further characterized in that said gas other than air is intermittently controlled so that the energy level at the lower end of the range is practically at the zero energy level. .Iaddend. .Iadd.12. The method of claim 9, being further characterized in that the pilot flame separately supplied with gas is also separately 
     
     
        supplied with combustion air. .Iaddend. .Iadd.13.  A gas infrared radiator comprising: a pre-chamber connectable to gas and air supply sources;   a combustion chamber;   a heat resistant barrier layer disposed between said pre-chamber and said combustion chamber;   said barrier layer having a plurality of individual conduits for supplying a gas and air mixture from said pre-chamber into said combustion chamber through each of said conduits;   pulse control means for supplying and intermittently varying the supply of fuel gas to said pre-chamber;   at least one nozzle for a pilot flame extending through said barrier layer and directed into the combustion chamber; and   means providing a separate gas supply to said nozzle independently of said pulse control means for supplying fuel gas to said pilot flame nozzle unaffected by said pulse control means. .Iaddend. .Iadd.14. A gas infrared radiator according to claim 13 wherein said separate gas supply includes means for continuously supplying gas for said pilot flame totally unaffected by the intermittent operation of said pulse control means. .Iaddend.