Forced convection heating furnace and method for heating glass sheets

A furnace for heating glass sheets comprising:

• a housing having a pair of side walls, a floor and a ceiling that cooperate to defined a heating chamber;
• a roll conveyor for conveying glass sheets through the heating chamber along a direction of conveyance;
• a plurality of forced convection heaters spaced along the direction of conveyance both below and above the roll conveyor within the housing, each forced convection heater including a gas burner assembly generally adjacent one of the housing side walls, the gas burner assembly including a delivery tube having an outer end and a gas burner mounted by the one side wall within the outer end of the delivery tube, and the delivery tube having an inner end that defines an outlet of the gas burner assembly through which heated products of combustion from the gas burner are supplied to the heating chamber at a location intermediate the housing side walls;
• and
• each forced convection heater also including a hot gas distributor located within the housing generally adjacent the other side wall and including an inlet that is spaced from the outlet of its gas burner assembly intermediate the housing side walls, the hot gas distributor having a suction fan for drawing the heated products of combustion from the outlet of the gas burner assembly together with spent recirculating gas in the heating chamber into the hot gas distributor through its inlet for mixing to provide heated gas, and the hot gas distributor having distribution openings through which the mixed heated gas is distributed to the conveyed glass sheets on the roll conveyor to provide heating of the glass sheets.

A furnace for heating glass sheets comprising:

• a housing having a pair of side walls, a floor and a ceiling that cooperate to define a heating chamber;
• a roll conveyor for conveying glass sheets through the heating chamber along a direction of conveyance;
• a plurality of forced convection heaters spaced along the direction of conveyance both below and above the roll conveyor within the housing, each forced convection heater including a gas burner assembly generally adjacent one of the housing side walls, the gas burner assembly including a delivery tube having an outer end and a gas burner mounted by the one side wall within the outer end of the delivery tube, the delivery tube having an inner end that defines an outlet of the gas burner assembly through which heated products of combustion from the gas burner are supplied to the heating chamber at a location intermediate the housing side walls, the outlet of each gas burner assembly including an adjustable damper at the inner end of the delivery tube for controlling the flow of the heated products of combustion into the heating chamber;
• and
• each forced convection heater also including a hot gas distributor located within the housing generally adjacent the other side wall and including an inlet that is spaced from the outlet of its gas burner assembly intermediate the housing side walls, the hot gas distributor having a suction fan for drawing the heated products of combustion from the outlet of the gas burner assembly together with spent recirculating gas in the heating chamber into the hot gas distributor through its inlet for mixing to provide heated gas, and the hot gas distributor having distribution openings through which the mixed heated gas is distributed to the conveyed glass sheets on the roll conveyor to provide heating of the glass sheets.

A method for heating glass sheets comprising:

• conveying glass sheets on a roll conveyor along a direction of conveyance within a heating chamber cooperatively defined by side walls, a floor and a ceiling of a housing;
• supplying heated products of combustion from a gas burner assembly mounted adjacent one side wall of the housing through an outlet of the gas burner assembly into the heating chamber at a location intermediate the housing side walls;
• drawing the heated products of combustion from the outlet of the gas burner assembly together with spent recirculating gas in the heating chamber into a hot gas distributor through an inlet thereof for mixing to provide heated gas;
• and
• distributing the mixed heated gas to the conveyed glass sheets on the roll conveyor to provide heating of the glass sheets.

A method for heating glass sheets comprising:

• conveying glass sheets on a roll conveyor along a direction of conveyance within a heating chamber cooperatively defined by side walls, a floor and a ceiling of a housing;
• burning gas in a plurality of gas burners to provide heated products of combustion within associated delivery tubes of a plurality gas burner assemblies spaced along the direction of conveyance both above and below the roll conveyor;
• supplying the heated products of combustion through outlets of the gas burner assemblies with the outlets provided by an inner ends of the delivery tubes for flow into the heating chamber at a location intermediate the housing side walls;
• drawing the heated products of combustion from the outlets of the gas burner assemblies together with spent recirculating gas in the heating chamber into inlets of hot gas distributors spaced along the direction of conveyance both below and above the roll conveyor through an inlet thereof for mixing to provide heated gas;
• mixing the heated products of combustion and the spent recirculating gas from the heating chamber within the hot gas distributors to provide mixed heated gas;
• and
• distributing the mixed heated gas upwardly and downwardly to the conveyed glass sheets on the roll conveyor to provide heating of the glass sheets.