초록 ▼

Methods and apparatus for regulating furnace combustion air flow are provided which measure a gaseous combustion product in furnace gas after combustion, generate a present signal responsive to the measurement and change flow rate of combustion air in response to the generated signal in a manner the

Methods and apparatus for regulating furnace combustion air flow are provided which measure a gaseous combustion product in furnace gas after combustion, generate a present signal responsive to the measurement and change flow rate of combustion air in response to the generated signal in a manner the same as flow rate was changed in response to a previously generated signal if the present signal relates to the previous signal in the manner the previous signal related to a signal ancestor thereto but change the flow rate of combustion air in response to the generated signal in a manner opposite the manner the flow rate was changed in response to the previously generated signal if the present signal relates to the previous signal in a manner opposite the manner the previous signal related to a signal immediately ancestor thereto.

대표청구항 ▼

Apparatus for regulating flow of combustion air to a furnace thereby to maintain a relatively optimum fuel-air mixture for high combustion efficiency in response to a measured level of carbon dioxide in furnace gas after combustion thereof, comprising: a. gas analyzer for sensing relative level of c

Apparatus for regulating flow of combustion air to a furnace thereby to maintain a relatively optimum fuel-air mixture for high combustion efficiency in response to a measured level of carbon dioxide in furnace gas after combustion thereof, comprising: a. gas analyzer for sensing relative level of carbon dioxide in furnace gas after combustion thereof and producing an electrical signal proportional to sensed carbon dioxide level; b. amplifier means, receiving said electrical signal from said gas analyzer, for boosting said signal to a second signal level; c. a first loop circuit having said second signal applied to respective terminals thereof, said first loop circuit including: i. an inductor defining an input coil of a relay; ii. a capacitor; iii. variable resistance means in series connection with said capacitor for tuning the resultant resistor-capacitor combination; iv. first switching means, in series with said capacitor-variable resistor combination, for open circuiting said resistor-capacitor combination with respect to said inductor; and v. second switching means, in parallel with said first switching means-resistor-capacitor combination, for short circuiting said first switching means-resistor-capacitor combination; d. said relay having its output connected in series with a second loop circuit; e. said second loop circuit including; i. a meter for visibly indicating current flow around said circuit; ii. an input coil to a second relay; iii. an output winding of a transformer; iv. rectifier means for rectifying said transformer output; and v. third switching means for opening said second loop circuit; f. said transformer having its input winding connected to line voltage; g. second relay output being movable between respective input terminals of an electric motor for selective connection thereof with line voltage; h. said electric motor having an output shaft rotating in respective opposite directions according to which of said respective input terminals is contacted by said second relay output; i. a damper, controlling flow of combustion air to said furnace, connected to said electric motor output shaft, opening further and closing further upon rotation of said motor shaft in respective opposite directions; j. fourth switching means for open circuiting said electric motor; and k. a timer operatively connected to said fourth switching means, for sequentially i. opening said second and fourth switching means while maintaining said first and third switching means closed; ii. opening said first and third switching means while maintaining said second and fourth switching means closed; iii. closing said second, third and fourth switching means while maintaining said first switching means open; iv. opening said second, third and fourth switching means while maintaining said first switching means closed; and v. closing said first and third switching means while maintaining said second and fourth switching means open.