Patents by Inventor Frederick J. Geary

Frederick J. Geary has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5209655
    Abstract: A heat exchanger system, a fuel control system therefor and methods of making the same are provided, the fuel control system having an electrical circuit means that comprises an ignition trial portion, a flame sensing control portion and a timer portion that comprises a counter having a plurality of outputs and a timer that clocks the output of the counter on each discharge of the timer, the timer portion also comprising a capacitor, a trial time resistor and a wait time resistor that are selectively placed in series with the capacitor by the counter when clocked to certain outputs by the timer to determine an ignition trial time period and a wait time period.
    Type: Grant
    Filed: June 18, 1992
    Date of Patent: May 11, 1993
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 5158447
    Abstract: A primary gas furnace control including a thermostatically controlled intermittent ignition system, the control being effective to monitor and control main gas valve action through use of flame rectification. The control features a slight delay on main valve dropout with flame failure and an extension of the ignition source into the main burner cycle to prevent nuisance recycling. If desired, the control may also include timed pilot valve, thermostat resettable, lockout as well as prepurge capability for use in applications requiring a furnace combustion chamber purge prior to an ignition cycle.
    Type: Grant
    Filed: January 25, 1990
    Date of Patent: October 27, 1992
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 5141431
    Abstract: A heat exchanger system, a fuel control system therefor and methods of making the same are provided, the fuel control system having an electrical circuit means that comprises an ignition trial portion, a flame sensing control portion and a timer portion that comprises a counter having a plurality of outputs and a timer that clocks the output of the counter on each discharge of the timer, the timer portion also comprising a capacitor, a trial time resistor and a wait time resistor that are selectively placed in series with the capacitor by the counter when clocked to certain outputs by the timer to determine an ignition trial time period and a wait time period.
    Type: Grant
    Filed: December 27, 1991
    Date of Patent: August 25, 1992
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 5085573
    Abstract: A hot surface ignition system for a gas furnace or the like, control device therefor and methods of making the same are provided, the system comprising a burner, a settable thermostat, an electrically operable gas valve, a control unit, and an electrically operable hot surface igniter disposed so as to be in the path of gas issuing from the burner that is adapted to be fed the gas from a source thereof through the gas valve when the control unit has been activated by the thermostat to operate the igniter and the gas valve in a certain sequence, the control unit having a lockout unit for deactivating the system should ignition of the gas issuing from the burner not take place by the end of the certain sequence, the control unit having a resetting unit for causing the control unit to be reactivated to be adapted to repeat the certain sequence of the system when the resetting unit is activated, the control unit being adapted to select the certain sequence to have one or more attempts of the control unit to ignit
    Type: Grant
    Filed: October 1, 1990
    Date of Patent: February 4, 1992
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 5003161
    Abstract: The combination of a heating element and a control unit therefor and methods of making and of operating the same are provided, the heating element normally being adapted to be operated by the continuous full wave pulses of a certain high voltage alternating current source and the control unit being operatively interconnected to the heating element for operatively interconnecting the heating element to a high voltage alternating current source, the control unit having an arrangement for operating the heating element with a certain repeating pattern of skipped full half-wave pulses of the source when the source has a higher voltage than the certain source.
    Type: Grant
    Filed: April 11, 1990
    Date of Patent: March 26, 1991
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4997361
    Abstract: A low cost hot surface ignition system particularly adapted for use in gas furnaces and the like, the system including low voltage control and timing circuitry effective to control a gas valve and high voltage ignition circuitry incorporating a hot surface silicon carbide igniter disposed in the path of incoming gas and in the heat of the flame when ignition is achieved to effect flame rectification resulting in flame sensing. The system also provides fail-safe operation or safety shutdown of the associated furnace if ignition is not achieved or in the event of a failure of a component of the system.
    Type: Grant
    Filed: June 13, 1989
    Date of Patent: March 5, 1991
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4976605
    Abstract: A hot surface ignition system for a gas furnace or the like, control device therefor and methods of making the same are provided, the system comprising a burner, a settable thermostat, an electrically operable gas valve, a control unit, and an electrically operable hot surface igniter disposed so as to be in the path of gas issuing from the burner that is adapted to be fed the gas from a source thereof through the gas valve when the control unit has been activated by the thermostat to operate the igniter and the gas valve in a certain sequence, the control unit having a lockout unit for deactivating the system should ignition of the gas issuing from the burner not take place by the end of the certain sequence, the control unit having a resetting unit for causing the control unit to be reactivated to be adapted to repeat the certain sequence of the system when the resetting unit is activated, the control unit being adapted to select the certain sequence to have one or more attempts of the control unit to ignit
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: December 11, 1990
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4971549
    Abstract: A control unit for a gas furnace that has an electrically operable pilot gas valve and an electrically operable main gas valve and a method of making the control unit are provided, the control unit comprising an electrical circuit having a gas valve section that comprises a silicon controlled rectifier and a first capacitor and a second capacitor so electrically interconnected together that the capacitors are adapted to be charged on each half wave cycle of a certain polarity of an alternative current source that is imposed on the circuit and that second capacitor is adapted to discharge through a relay coil that controls the gas valve to energize that relay coil only when the silicon controlled rectifier conducts, the silicon controlled rectifier being adapted to conduct only when the first capacitor is discharged, another section of the electrical circuit being adapted to discharge the first capacitor only on each half wave cycle of the other polarity of the alternative current source.
    Type: Grant
    Filed: July 14, 1989
    Date of Patent: November 20, 1990
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4935606
    Abstract: The combination of a heating element and a control unit therefor and methods of making and of operating the same are provided, the heating element normally being adapted to be operated by the continuous full wave pulses of a certain high voltage alternating current source and the control unit being operatively interconnected to the heating element for operatively interconnecting the heating element to a high voltage alternating current source, the control unit having an arrangement for operating the heating element with a certain repeating pattern of skipped full half-wave pulses of the source when the source has a higher voltage than the certain source.
    Type: Grant
    Filed: December 14, 1988
    Date of Patent: June 19, 1990
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4915614
    Abstract: A primary gas furnace control including a thermostatically controlled intermittent ignition system, the control being effective to monitor and control main gas valve action through use of flame rectification. The control features a slight delay on main valve dropout with flame failure and an extension of the ignition source into the main burner cycle to prevent nuisance recycling. If desired, the control may also include time pilot valve, thermostat resettable, lockout as well as prepurge capability for use in applications requiring a furnace combustion chamber purge prior to an ignition cycle.
    Type: Grant
    Filed: March 30, 1989
    Date of Patent: April 10, 1990
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4865539
    Abstract: A control unit for a gas furnace that has an electrically operable pilot gas valve and an electrically operable main gas valve and a method of making the control unit are provided, the control unit comprising an electrical circuit having a gas valve section that comprises a silicon controlled rectifier and a first capacitor and a second capacitor so electrically interconnected together that the capacitors are adapted to be charged on each half wave cycle of a certain polarity of an alternative current source that is imposed on the circuit and that the second capacitor is adapted to discharge through a relay coil that controls the gas valve to energize that relay coil only when the silicon controlled rectifier conducts, the silicon controlled rectifier being adapted to conduct only when the first capacitor is discharged, another section of the electrical circuit being adapted to discharge the first capacitor only on each half wave cycle of the other polarity of the alternative current source.
    Type: Grant
    Filed: August 23, 1988
    Date of Patent: September 12, 1989
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4856983
    Abstract: A low cost hot surface ignition system particularly adapted for use in gas furnaces and the like, the system including low voltage control and timing circuitry effective to control a gas valve and high voltage ignition circuitry incorporating a hot surface silicon carbide igniter disposed in the path of incoming gas and in the heat of the flame when ignition is achieved to effect flame rectification resulting in flame sensing. The system also provides fail-safe operation or safety shutdown of the associated furnace if ignition is not achieved or in the event of a failure of a component of the system.
    Type: Grant
    Filed: March 9, 1988
    Date of Patent: August 15, 1989
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4836770
    Abstract: A primary gas furnace control including a thermostatically controlled intermittent ignition system, the control being effective to monitor and control main gas valve action through use of flame rectification. The control features a slight delay on main valve dropout with flame failure and an extension of the ignition source into the main burner cycle to prevent nuisance recycling. If desired, the control may also include timed pilot valve, thermostat resettable, lockout as well as prepurge capability for use in applications requiring a furnace combustion chamber purge prior to an ignition cycle.
    Type: Grant
    Filed: April 22, 1988
    Date of Patent: June 6, 1989
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4809128
    Abstract: The combination of a heating element and a control unit therefor and methods of making and of operating the same are provided, the heating element normally being adapted to be operated by the continuous full-wave pulses of a certain high voltage alternating current source for a predetermined time period so as to provide a desired function thereof and the control unit being operatively interconnected to the heating element and having a first arrangement for operatively interconnecting the heating element to that certain high voltage alternating current source for the predetermined time period so as to provide a desired function thereof, the control unit having a second arrangement for operating the heating element with a certain repeating pattern of skipped complete half-wave pulses of another source of high voltage alternating current for the predetermined time period when that other source has a higher voltage than the certain source so that the heating element will not be adversely affected by the other sou
    Type: Grant
    Filed: June 23, 1987
    Date of Patent: February 28, 1989
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4755132
    Abstract: A hot surface ignition system for a gas furnace and method of making the same are provided, the system comprising a high voltage circuit for being connected to a source of high voltage AC current, the high voltage circuit having a hot surface igniter therein and disposed in the path of gas issuing from a burner that is adapted to be fed gas from a source thereof through an electrically operated gas valve, a low voltage circuit for being connected to a source of low voltage AC current, the low voltage circuit having the gas valve therein and having a thermostatic switch therein controlling the energization of the low voltage circuit with the low voltage AC current, a first relay unit having contacts in the high voltage circuit and controlling the energizaiton of the igniter with the high voltage AC current, and another relay unit having contacts in the low voltage circuit and controlling the energization of the gas valve, the other relay unit comprising two separate relays respectively having contacts that are
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: July 5, 1988
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4755133
    Abstract: A primary gas furnace control including a thermostatically controlled intermittent ignition system, the control being effective to monitor and control main gas valve action through use of flame rectification. The control features a slight delay on main valve dropout with flame failure and an extension of the ignition source into the main burner cycle to prevent nuisance recycling. If desired, the control may also include timed pilot valve, thermostat resettable, lockout as well as prepurge capability for use in applications requiring a furnace combustion chamber purge prior to an ignition cycle.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: July 5, 1988
    Assignee: Robertshaw Control Company
    Inventor: Frederick J. Geary
  • Patent number: 4746284
    Abstract: A low cost hot surface ignition system particularly adapted for use in gas furnaces and the like, the system including low voltage control and timing circuitry effective to control a gas valve and high voltage ignition circuitry incorporating a hot surface silicon carbide igniter disposed in the path of incoming gas and in the heat of the flame when ignition is achieved to effect flame rectification resulting in flame sensing. The system also provides fail-safe operation or safety shutdown of the associated furnace if ignition is not achieved or in the event of a failure of a component of the system.
    Type: Grant
    Filed: October 10, 1986
    Date of Patent: May 24, 1988
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4711628
    Abstract: A hot surface ignition system for a gas furnace and method of making the same are provided, the system comprising a high voltage circuit for being connected to a source of high voltage AC current, the high voltage circuit having a hot surface igniter therein and disposed in the path of gas issuing from a burner that is adapted to be fed gas from a source thereof through an electrically operated gas valve, a low voltage circuit for being connected to a source of low voltage AC current, the low voltage circuit having the gas valve therein and having a thermostatic switch therein controlling the energization of the low voltage circuit with the low voltage AC current, a first relay unit having contacts in the high voltage circuit and controlling the energization of the igniter with the high voltage AC current, and another relay unit having contacts in the low voltage circuit and controlling the energization of the gas valve, the other relay unit comprising two separate relays respectively having contacts that are
    Type: Grant
    Filed: July 18, 1986
    Date of Patent: December 8, 1987
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4680005
    Abstract: A primary gas furnace control including a thermostatically controlled intermittent ignition system, the control being effective to monitor and control main gas valve action through use of flame rectification. The control features a slight delay on main valve dropout with flame failure and an extension of the ignition source into the main burner cycle to prevent nuisance recycling. If desired, the control may also include timed pilot valve, thermostat resettable, lockout as well as prepurge capability for use in applications requiring a furnace combustion chamber purge prior to an ignition cycle.
    Type: Grant
    Filed: June 26, 1986
    Date of Patent: July 14, 1987
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary
  • Patent number: 4643668
    Abstract: A low cost hot surface ignition system particularly adapted for use in gas furnaces and the like, the system including low voltage control and timing circuitry effective to control a gas valve and high voltage ignition circuitry incorporating a hot surface silicon carbide igniter disposed in the path of incoming gas and in the heat of the flame when ignition is achieved to effect flame rectification resulting in flame sensing. The system also provides fail-safe operation or safety shutdown of the associated furnace if ignition is not achieved or in the event of a failure of a component of the system.
    Type: Grant
    Filed: June 25, 1984
    Date of Patent: February 17, 1987
    Assignee: Robertshaw Controls Company
    Inventor: Frederick J. Geary