EP1253376A2 - Système de pilote à gaz et procédé de surveillance du niveau d'oxygène et dispositif à gaz comprenant ce système - Google Patents

Système de pilote à gaz et procédé de surveillance du niveau d'oxygène et dispositif à gaz comprenant ce système Download PDF

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Publication number
EP1253376A2
EP1253376A2 EP02009599A EP02009599A EP1253376A2 EP 1253376 A2 EP1253376 A2 EP 1253376A2 EP 02009599 A EP02009599 A EP 02009599A EP 02009599 A EP02009599 A EP 02009599A EP 1253376 A2 EP1253376 A2 EP 1253376A2
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EP
European Patent Office
Prior art keywords
pilot
oxygen level
gas
nozzle
flame
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP02009599A
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German (de)
English (en)
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EP1253376A3 (fr
Inventor
David Deng
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Individual
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Individual
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Filing date
Publication date
Priority claimed from US09/844,974 external-priority patent/US20020160326A1/en
Application filed by Individual filed Critical Individual
Publication of EP1253376A2 publication Critical patent/EP1253376A2/fr
Publication of EP1253376A3 publication Critical patent/EP1253376A3/fr
Withdrawn legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N5/00—Systems for controlling combustion
    • F23N5/02—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium
    • F23N5/14—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using thermo-sensitive resistors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/46—Details, e.g. noise reduction means
    • F23D14/72—Safety devices, e.g. operative in case of failure of gas supply
    • F23D14/725—Protection against flame failure by using flame detection devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N5/00—Systems for controlling combustion
    • F23N5/02—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium
    • F23N5/08—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using light-sensitive elements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N5/00—Systems for controlling combustion
    • F23N5/02—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium
    • F23N5/12—Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using ionisation-sensitive elements, i.e. flame rods
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2207/00—Ignition devices associated with burner
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2208/00—Control devices associated with burners
    • F23D2208/10—Sensing devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D2900/00—Special features of, or arrangements for burners using fluid fuels or solid fuels suspended in a carrier gas
    • F23D2900/00014—Pilot burners specially adapted for ignition of main burners in furnaces or gas turbines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23N—REGULATING OR CONTROLLING COMBUSTION
    • F23N2227/00—Ignition or checking
    • F23N2227/22—Pilot burners

Definitions

  • the present inventions relate generally to gas pilots and, more particularly, to the oxygen level detection systems associated with gas pilots.
  • Gas pilot systems are associated with a wide variety of gas fueled devices. Such devices include, but are not limited to, vented gas heaters, which include pipes or conduits that are used to vent exhaust to the atmosphere, vent-free gas heaters, vented and vent-free gas log heater, vented and vent-free fireplace systems, water heaters, vented and vent-free stoves, and ovens.
  • vented gas heaters which include pipes or conduits that are used to vent exhaust to the atmosphere
  • vent-free gas heaters vented and vent-free gas log heater
  • vented and vent-free fireplace systems vented and vent-free fireplace systems
  • water heaters vented and vent-free stoves, and ovens.
  • the most common types of gas fuel are natural gas and propane.
  • a gas pilot system typically includes an ignition device, such as an electrode, and a pilot having a small nozzle. A pilot flame is formed when gas from the nozzle is ignited by the ignition device. The pilot flame is then used to ignite the gas that is supplied to the burner(s) of the gas fueled device during
  • the level of oxygen in the air is typically about 20.9%. It is important that the oxygen level in a room in which a gas fueled device is used remain at or near 20.9%, both for proper combustion and safety purposes. An adequate supply of fresh air will maintain the oxygen level at or near the desired level. In buildings with loose structures, such as houses made of wood, an adequate supply of fresh air will enter via wall spaces as well as door and window frames. Other buildings are more tightly sealed. Here, steps should be taken to insure that fresh air is supplied.
  • ODS system oxygen depletion sensor system
  • thermocouple TC to detect the presence of a pilot flame F when it is in the "normal" oxygen level position (oxygen level greater than or equal to 21%) illustrated in FIGURE 1A or the "relatively low” oxygen level position (oxygen level between 18.2% and 19.2%) illustrated in FIGURE 1B.
  • gas will continue to flow to the pilot and burner because the voltage generated by the thermocouple TC, and received by the ODS system controller, will be within an allowable range.
  • the pilot flame F will move to the location illustrated in FIGURE 1C.
  • thermocouple TC will drop, as will the voltage produced thereby.
  • the voltage drop will cause the ODS system to cut off the supply of gas to the pilot and burner.
  • some ODS systems also include a second thermocouple that is used to generate a warning when the pilot flame moves to the "relatively low" oxygen level position.
  • the pilot flame F will, for example, often bounce back and forth between the "relatively low” position and the "unsafe” position for 15 seconds and, during this time, the temperature at the thermocouple TC will not drop to a level low enough to cause the ODS system to cut off the supply of gas to the pilot and burner.
  • the inventor herein has determined that the conventional methods of monitoring the pilot flame introduce unnecessary delays into the operation of conventional ODS systems.
  • a pilot system in accordance with one embodiment of a present invention includes a pilot having a nozzle and a sensor adjacent to the nozzle that senses or measures a property other than temperature in the pilot area.
  • a gas fueled device in accordance with a present invention includes a burner, a nozzle and a sensor adjacent to the nozzle that senses or measures a property other than temperature in the pilot area.
  • Exemplary sensors include light sensors and electrical resistance measurement devices. The sensor determines whether or not the pilot flame is in a predetermined position relative to the nozzle. In a preferred implementations, the sensor determines when the pilot flame is not in either of the "normal" oxygen level and "relatively low” oxygen level positions, i.e. when the pilot flame is in the "unsafe" oxygen level position.
  • non-temperature based sensors are capable of detecting movement of the pilot flame the instant that the pilot flame first moves to the "unsafe" oxygen level position, even if it quickly bounces back to the "relatively low” oxygen level position.
  • ODS systems employing the present pilot system will, therefore, be able to make an "unsafe" oxygen level determination much more quickly than ODS systems that employ a conventional thermocouple-based pilot flame monitoring arrangement.
  • ODS systems employing the present pilot system will also be able to, for example, cut off the supply of gas to a pilot and burner much faster than ODS systems that employ a conventional thermocouple-based pilot flame monitoring arrangement.
  • a pilot system 10 in accordance with a preferred embodiment of a present invention includes a pilot 12 having a gas/air mixing chamber 14 and a nozzle 16.
  • Gas G enters the mixing chamber 14 through a small gas orifice 18, while air A enters the mixing chamber through a pair of small air orifices 20.
  • the gas/air mixture G/A exits the mixing chamber 14 through an outlet orifice 22. Mixing continues as the gas/air mixture G/A travels through a tube 24 to the nozzle 16.
  • the gas G in the gas/air mixture G/A is ignited by the L-shaped electrode 26 of an ignitor 28 to create the pilot flame F.
  • the inlet and outlet orifices 18 and 22 are preferably formed from a relatively hard material. In a preferred implementation, the orifices are formed in a ruby or other hard precious stone that is mounted in a copper frame.
  • the size of the orifices 18 and 20 depends on the fuel being used. For example, when the fuel is natural gas supplied at a pressure of 6 inches of mercury, the orifice 18 is approximately 0.38 mm in diameter and the orifice 18 is approximately 0.46 mm in diameter when the natural gas is supplied at a pressure of 3 inches of mercury. In both cases, the orifices 20 are each approximately 3 mm in diameter. The orifice 18 is approximately 0.22 mm in diameter and the orifices 20 are each approximately 3.2 mm in diameter when the fuel is liquid propane gas supplied at about 8 to 11 inches of mercury. The outlet orifice 22 is approximately 4 mm. The outlet pressure should be about 8 to 11 inches of mercury when the fuel is liquid propane gas and about 3 to 6 inches of mercury when the fuel is natural gas.
  • ODS system may also be augmented by controlling movement of the pilot flame F through use of the relationship between the diameter of the pilot nozzle 16, the fuel pressure, the distance of the electrode 26 from the nozzle as well as the location of the electrode relative 26 to the nozzle centerline, and the level of oxygen in the air.
  • the diameter of the pilot nozzle 16 is approximately 0.23 mm ( ⁇ 0.005 mm) and the gas pressure is between 8 and 11 inches of mercury.
  • the downwardly extending portion of the L-shaped electrode 26 is offset with respect to the centerline of the pilot nozzle 16 by 3.00 mm and is spaced approximately 3.50 mm from the nozzle. Such an arrangement reduces the speed of gas flow, thereby increasing the duration and effectiveness of gas/air mixing, and also reduces the tendency of the pilot flame F to bounce around, as compared to conventional S-shaped electrodes.
  • the exemplary pilot systems disclosed herein also includes an oxygen depletion sensor that may be used in a ODS systems in the manner described below with reference to FIGURES 11-13.
  • the oxygen depletion sensor is preferably a sensor that measures or senses a property other than temperature and a variety of such oxygen depletion sensors are described below.
  • the oxygen depletion sensor in the exemplary pilot system 10 illustrated in FIGURES 2A, 3 and 4 is a light sensor that senses light from the pilot flame F. Any suitable light sensor may be employed so long as it is capable of detecting the presence and absence of light emitted by the pilot flame F.
  • the pilot system 10 is provided with an infrared sensing device 30 having a sensing element 32 that is positioned adjacent to the pilot nozzle 16 and pilot flame F.
  • a suitable infrared sensing device is manufactured by Shanghai Infrared Appliances Co., located in Shanghai, China.
  • the pilot flame F generates infrared electromagnetic radiation (i.e.
  • electromagnetic radiation with wavelengths between 750 nanometers and 1 millimeter which is sensed by the sensing element 32 when the pilot flame is in the "normal" oxygen level position illustrated in FIGURE 2A (oxygen level greater than or equal to 21%) and, in the illustrated embodiment, in the "relatively low” oxygen level position illustrated in FIGURE 2B (oxygen level between 18.2% and 19.2%).
  • the infrared radiation causes the sensing element 32 to generate a flame signal which indicates that the flame is in an allowable (or "safe") position.
  • a suitable light sensor is one that senses visible light (not shown), such as those produced by China Wuxi Light Appliances Co, located in Wuxi, China.
  • the sensing device 30 will stop generating a flame signal which indicates that the pilot flame is in an allowable position.
  • the signal from the sensing device may drop to zero, or simply to a level lower than the expected level, when the pilot flame F moves from the "normal" or "relatively low” oxygen level position to the "unsafe” oxygen level position.
  • the present sensing device 30 will immediately indicate that the oxygen level has dropped to an "unsafe” level because it will fail to produce the expected flame signal the first time that the pilot flame moves out beyond of the "relatively low” position to the "unsafe” position.
  • the exemplary pilot system 10 may also be provided with a light shield 34 that is positioned above the nozzle 16 around the area that will be occupied by the pilot flame F when the oxygen level is "normal.”
  • the light shield 34 which is preferably opaque, non-reflective and formed from metal, includes a slot 36 that faces the sensing element 32.
  • the light shield 34 prevents the sensing element 32 from being effected by stray light that could result in the expected flame signal when the flame is actually in the "unsafe" oxygen level position. As such, the sensing element 32 will only be effected by the infrared or visible electromagnetic radiation from the pilot flame F which passes through the slot 36 when the pilot flame is in the "normal” and "relatively low” oxygen level positions.
  • the light shield 34 is about 7.2 mm in diameter and about 10 mm in length, while the slot 36 is about 3.6 mm wide.
  • the components may be reconfigured such that the sensing device 30 will stop generating a signal which indicates that the pilot flame F is in an allowable position the instant that the pilot flame F moves out of the "normal" oxygen level position to either the "relatively low” oxygen level position or the "unsafe” oxygen level position.
  • the light shield 34 could be provided with a small hole that faces the sensing element 32 in place of the slot 36 in order to substantially reduce the amount of light from the pilot flame F that will reach the sensing element when the pilot flame moves to the "relatively low” oxygen level position.
  • the exemplary pilot system 10 is also provided with a bracket system 38 that fixes the positions of the various elements of the pilot system relative to one another.
  • the exemplary bracket system 38 includes a L-shaped main bracket 40 having a first portion 42 that is mounted on the pilot 12 adjacent to the nozzle 16.
  • the light shield 34 is supported by the first portion 42.
  • the ignitor 28 and sensing device 30 are mounted on a second portion 44 of the main bracket 40 and are fixed in place by a clamp 46.
  • the clamp 46 may be secured to the main bracket 40 with a screw 48 or other suitable fastening device.
  • a pair of mounting apertures 50 and 52 are formed in the main bracket 40 so that the pilot system 10 may be easily mounted within a gas fueled device.
  • the end of the sensing element 32 is about 20 to 22 mm from the nozzle 16 and about 26 to 36 mm above the nozzle (measured with the system 10 oriented such that the pilot 12 extends vertically).
  • pilot system 10' is substantially similar to pilot system 10 and similar elements are represented by similar reference numerals.
  • the pilot system 10' includes a sensor that measures the electrical resistance of whatever gas (e.g. pure air, pure gas or a gas/air mixture) is in the area adjacent to the nozzle 16. Any suitable resistant measurement device may be employed so long as it is capable of measuring the electrical resistance of the gas in the area adjacent to the nozzle.
  • the exemplary pilot system 10' is provided with an electrical resistance measuring device 54 including an sensing device 56 that is positioned adjacent to the pilot nozzle 16 and pilot flame F.
  • the sensing device 56 includes a pair of generally L-shaped electrodes 58a and 58b positioned above the nozzle 16 in the position shown in Figure 6.
  • a space 60 of approximately 3 mm separates the free ends of the L-shaped electrodes 58a and 58b, which are located in the area that will be occupied by the outer edge of the pilot flame F when the pilot flame in the "normal" oxygen level position illustrated in Figure 5A.
  • the pilot system 10' also includes a shield 34' with a slot 36' that accommodates the L-shaped electrodes 58a and 58b.
  • a constant current (I) is applied to the sensing device 56 by the electrical resistance measuring device 54 and the voltage (V) across the electrodes 58a and 58b is measured by the measuring device.
  • the measuring device 54 also produces a signal indicative of the electrical resistance in the area adjacent to the nozzle 16.
  • the high temperature at the outer edge of the pilot flame F causes the gas in the gas/air mixture G/A to be ionized and electrical resistance is inversely related to the level of gas ionization.
  • the electrical resistance of the gas in the region adjacent to the nozzle 16 will be approximately 8-12 M ⁇ (i.e. 8-12x10 6 ⁇ ) when the pilot flame is in the "normal" oxygen level position (oxygen level greater than or equal to 21%) illustrated in FIGURE 5A.
  • the resistance level will be significantly lower when the pilot flame F is in the region adjacent to the nozzle 16 (FIGURE 5A) than it will be when the pilot flame F is in the "relatively low” oxygen level position (oxygen level between 18.2% and 19.2%) illustrated in FIGURE 5B.
  • the electrical resistance will rise to about 20 M ⁇ when the pilot flame F is in the "relatively low” oxygen level position illustrated in FIGURE 5B because the hot outer edge of the pilot flame F will no longer be present in the region where resistance is being measured. This results in a reduction in temperature in the region adjacent to the nozzle 16 and a correspondingly lower level of gas ionization.
  • the resistance will be about 80-100 M ⁇ when the pilot flame F is in the "unsafe" level position (oxygen level below 18.2%) illustrated in FIGURE 5C because the temperature and gas ionization levels in the region adjacent to the nozzle 16 will fall even further.
  • the difference in resistance will be detected by the measuring device 54 within about 1 second from the time at which the pilot flame F moves. This is true whether pilot flame F is moving from the "normal" oxygen level position to the "relatively low” oxygen level position, or from the “relatively low” oxygen level position to the "unsafe” oxygen level position. Thus, even in those instances where the pilot flame F jumps back and forth between the "normal” and “relatively low” oxygen level positions, the present measuring device 54 will immediately indicate that the oxygen level has dropped to a "relatively low” level because the resistance measured thereby will increase beyond the 8-12 M ⁇ range the first time that the pilot flame F moves out of the "normal" oxygen level position to the "relatively low” oxygen level position.
  • the present measuring device 54 will immediately indicate that the oxygen level has dropped to an "unsafe” level because the resistance measured thereby will increase beyond the 20 M ⁇ range the first time that the pilot flame moves out of the "relatively low” oxygen level position to the "unsafe” oxygen level position.
  • Pilot system 10 is substantially similar to pilot system 10' and similar elements are represented by similar reference numerals.
  • the pilot system 10" also includes a sensor that measures the electrical resistance of whatever gas (e.g. pure air, pure gas or a gas/air mixture) is in the area adjacent to the nozzle 16.
  • an electrical resistance measuring device 62 includes a sensing device 64 that is positioned adjacent to the pilot nozzle 16 and pilot flame F.
  • the sensing device 64 includes a first electrode that defines an enclosed open area, such as the exemplary annular electrode 66 that defines an open area 68, and a second electrode, such as the exemplary L-shaped electrode 70, which has a portion that is positioned within the open area.
  • the L-shaped electrode 70 is also used to ignite the gas in the exemplary embodiment.
  • the annular electrode 66 in the exemplary embodiment is preferably formed from stainless steel wire that is about 1 mm in diameter.
  • the annular electrode 66 also has an outer diameter of about 8 mm and is positioned about 8 mm above the nozzle 16 so that it occupies the area that will be occupied by the outer edge of the pilot flame F when the pilot flame in the "normal" oxygen level position illustrated in Figure 7A.
  • the exemplary L-shaped electrode 70 is also formed from stainless steel wire that is about 1 mm in diameter. As such, within the open area 68, the distance D ( Figure 9) between the L-shaped electrode 70 and the inner surface of the annular electrode 66 is about 2.5 mm.
  • the electrodes 66 and 70 are preferably supported by insulative structures 72 and 74.
  • a constant current (I) is applied to the sensing device 64 by the measuring device 62 and the voltage (V) across the electrodes 66 and 70 is measured by the measuring device.
  • the measuring device 62 also produces a signal indicative of the electrical resistance in the area adjacent to the nozzle 16.
  • the electrical resistance of the gas in the region adjacent to the nozzle 16 will be approximately 8-12 M ⁇ (i.e. 8-12x10 6 ⁇ ) when the pilot flame is in the "normal" oxygen level position (oxygen level greater than or equal to 21%) shown in FIGURE 7A.
  • the resistance level will increase significantly when the pilot flame F moves out of the "normal" oxygen level position adjacent to the nozzle 16 (FIGURE 7A) to the "relatively low” oxygen level position (oxygen level between 18.2% and 19.2%) illustrated in FIGURE 7B or to the "unsafe” oxygen level position (oxygen level below 18.2%).
  • the difference in resistance will be detected by the measuring device 62 within about 1 second from the time at which the pilot flame F moves. This is true whether pilot flame F is moving from the "normal" oxygen level position to the "relatively low” oxygen level position, or to the "unsafe” oxygen level position.
  • the present measuring device 62 will immediately indicate that the oxygen level has dropped to a "relatively low” level because the resistance measured thereby will increase beyond the 8-12 M ⁇ range the first time that the pilot flame F moves out of the "normal" oxygen level position to the "relatively low” oxygen level position.
  • the present measuring device 62 may be used to immediately indicate that the oxygen level has dropped to an "unsafe” level the first time that the pilot flame F moves to the "unsafe" oxygen level position and the resistance exceeds 20 M ⁇ .
  • pilot system 10''' is illustrated in Figures 10A-10C.
  • Pilot system 10"' is substantially similar to pilot system 10 and similar elements are represented by similar reference numerals.
  • pilot system 10''' includes a pilot 12 having a gas/air mixing chamber 14 and a nozzle 16.
  • the gas G in the gas/air mixture G/A is ignited by an electrode 26' of an ignitor 28, which is supported by a bracket system 38', to create the pilot flame F.
  • the oxygen depletion sensor is a light sensor that senses light associated with the ignition electrode 26' instead of light from the pilot flame F.
  • the electrode 26' will glow when the flame F is in the "normal" oxygen level position (oxygen level greater than or equal to 21%) shown in FIGURE 10A or the "relatively low” oxygen level position (oxygen level between 18.2% and 19.2%) shown in FIGURE 10B, but will stop glowing (or will fail to create a sufficiently detectable amount of light if only glowing slightly) when the pilot flame F moves to the "unsafe" oxygen level position (oxygen level below 18.2%) shown in FIGURE 10C.
  • the sensed light from the electrode may be either visible or infrared, depending on the type of sensor used.
  • a sensing device 30 having a sensing element 32 is positioned adjacent to the electrode 26'.
  • Any suitable light sensor may be employed so long as it is capable of detecting the presence or absence of light emitted by the electrode 26'.
  • the electrode 26' When the pilot flame F moves beyond the "relatively low" oxygen level position, the electrode 26' will stop glowing and the sensing device 30 will stop generating a flame signal which indicates that the pilot flame is in an allowable position. The signal may drop to zero, or simply to a level lower than an expected level. Alternatively, the electrode 26' may be repositioned so that it will stop glowing when the pilot flame moves beyond the "normal" oxygen level position.
  • heaters are one example of a gas fueled device in accordance with the present inventions.
  • An exemplary heater 100 is shown in FIGURE 11. Such a heater may be fueled by natural gas, propane gas or other appropriate fuels.
  • the exemplary heater 100 includes a housing 102 mounted on a base 104.
  • the housing 102 includes a heating chamber 106 which contains a plurality of heat emitting ceramic infrared burner plaques 108 and is covered by a grill 110.
  • the housing 102 also includes a plurality of air circulation vents 112 and 114. Air enters the housing through vent 112 and exits through the heating chamber grill 110 and the vent 114.
  • a pair of handles may also be provided on the sides of the housing.
  • the heater controls are located on the top portion 116 of the housing 102 in the exemplary heater 100. These controls include an on/off button 118, an ignition/pilot button 120, and a burner control knob 122 that is used to block/permit the flow of gas to the pilot 12 and to select the number of burners to which fuel will be supplied.
  • the on/off button 118 and the ignition/pilot button 120 are part of a control device 124 which, in the exemplary control embodiment, includes an electronic controller 125 such as a control circuit, microcontroller, microprocessor or other suitable control apparatus.
  • a propane gas-fueled heating assembly that may be used in conjunction with the housing 102 shown in FIGURE 11 includes five burners 126, each of which consists of an infrared ceramic plaque 108 that is secured to a corresponding burner box 128. The number of burners may, however, be increased or decreased to suit particular applications. An upper burner deflector bracket 130 and lower burner deflector bracket 132 are also shown. Additionally, although the propane gas-fueled heating assembly illustrated in FIGURE 12 includes the exemplary pilot system 10''' illustrated in Figures 10A-10C, any of the other pilot systems illustrated herein (i.e. systems 10, 10' and 10") may be employed in its place.
  • Propane gas is supplied to the pilot system and burners in the following manner. Turning first to the pilot system, and referring to FIGURES 12 and 13, the heater is placed in the pilot mode by turning the control knob 122 from the OFF position to the PILOT position and then depressing the knob and holding it in place. This allows gas to flow to the pilot 12 through a gas line 139. The on/off button 118 is then pressed to supply power to the system.
  • pulses of power will be supplied to the ignition electrode 26' by way of a connection line 140. So long as the user continues to holds the ignition/pilot button 120 and a pilot flame has not been lit, the pulses will continue for 20 seconds and then cease for 10 seconds with this pattern repeating for 5 minutes. The system will shut of if there is no pilot flame at the end of the 5 minute period.
  • the pilot flame sensing device associated with the pilot system (the sensing device 30 in pilot system 10''', for example) will send a signal to the control 124 by way of a connection line 142 which indicates that a pilot flame is present.
  • the controller 125 will then cause a magnetic valve unit 144, which is normally closed, to open so that the supply of gas to the pilot 12 will be maintained when the user releases the control knob 122.
  • the opening of the magnetic valve unit 144 will also allow the user to supply gas to the burners 126.
  • the exemplary heater 100 includes LOW, MEDIUM and HIGH heat output settings which correspond to one, three or five burners 126 receiving gas. The heat output settings are selected by rotating the control knob 122.
  • heaters in accordance with the present invention may also be constructed in such a manner that all of the burners will be used whenever the heater is in operation and the amount of gas supplied to the burners will be controlled by a thermostat.
  • the flame sensing device (the sensing device 30 in pilot system 10''', for example) and controller 125 form an ODS system that may operate in the following manner.
  • the sensing device 30 will stop generating a flame signal which indicates that the pilot flame is in an allowable position.
  • the controller 125 will, as a result, immediately close the magnetic valve 144 that allows gas to pass to the pilot 12 and the burners 126.
  • the heater 100 may, if desired, be provided with an audio and/or visual alarm that is triggered by the controller 125 when the valve 144 is closed by the controller in response to an "unsafe" oxygen level detection.
  • the present inventions may be incorporated in heaters which do not have a thermostatic control system.
  • the "unsafe,” "low” and “normal” oxygen level percentages discussed above may be varied if desired.
  • the exemplary pilot system may also be incorporated into other gas fueled devices such as water heaters, stoves, ovens and other types of heaters.
  • the pilot, sensing device and controller could also be reconfigured and repositioned such that the sensing device senses the flame when it is in the "unsafe" oxygen level position and this sensing results in closure of the gas valve(s). It is intended that the scope of the present inventions extends to all such modifications and/or additions.
  • the inventions herein also include a gas fueled device comprising a burner, a pilot including a nozzle associated with the burner, and a measurement device adjacent to the nozzle that measures a property other than temperature.
  • the burner in such a gas fueled device may, for example, be a ceramic plaque.
  • the measurement device in such a gas fueled may be an electrical resistance measurement device such as, for example, a device that includes a pair of spaced electrodes.
  • the gas fueled device may, for example, include an ignitor positioned adjacent to the nozzle such that the electrical resistance measurement device is located between the nozzle and the ignitor.
  • the measurement device may, alternatively, be sensor that senses electromagnetic radiation, such as a light sensor or an infrared light sensor.
  • the gas fueled device may, for example, include an ignitor positioned adjacent to the nozzle that emits electromagnetic radiation when heat by the pilot flame and sensor will sense electromagnetic radiation from the ignitor.
  • the pilot in such a gas fueled device may, for example, be constructed such that the pilot flame will be located in a first position in response to a first oxygen level and a second position in response to a second oxygen level, the second oxygen level being less than the first oxygen level.
  • the measurement device will measure a level of the property other than temperature that is indicative of an allowable oxygen level when the pilot flame is in the first position and will not measure a level of the property other than temperature that is indicative of an allowable oxygen level when the pilot flame is in the second position.
  • the gas fueled device may, for example, include a gas inlet operably connected to the pilot and a control device operably connected to the measurement device that prevents gas flow from the gas inlet to the pilot when the measurement device does not measure a level of the property other than temperature indicative of an allowable oxygen level.
  • the gas fueled device may, for example, include a gas inlet operably connected to the burner and a control device operably connected to the measurement device that prevents gas flow from the gas inlet to the burner when the measurement device does not measure a level of the property other than temperature indicative of an allowable oxygen level.
  • the inventions herein also include a method of monitoring a pilot flame produced by a pilot comprising the steps of determining whether the pilot flame is located in a predetermined region associated with the pilot by sensing a property other than temperature and preventing gas from flowing to the pilot in response to a determination that the pilot flame is not in the predetermined region.
  • the step of determining whether the flame is located in the predetermined region may, for example, comprise measuring electrical resistance in the predetermined region.
  • the step of determining whether the pilot flame is located in a predetermined region may, for example, comprise determining whether the pilot flame is located between the nozzle and the ignitor.
  • the step of determining whether the flame is located in the predetermined region may, for example, comprise sensing light in the predetermined region.
  • the step of determining whether the pilot flame is located in a predetermined region may, for example, comprise sensing light emitted from the ignitor.
EP02009599A 2001-04-26 2002-04-26 Système de pilote à gaz et procédé de surveillance du niveau d'oxygène et dispositif à gaz comprenant ce système Withdrawn EP1253376A3 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US09/844,974 US20020160326A1 (en) 2001-04-26 2001-04-26 Gas pilot system and method having improved oxygen level detection capability and gas fueled device including the same
US844974 2001-04-26
US10/103,540 US20020160325A1 (en) 2001-04-26 2002-03-20 Gas pilot system and method having improved oxygen level detection capability and gas fueled device including the same
US103540 2002-03-20

Publications (2)

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EP1253376A2 true EP1253376A2 (fr) 2002-10-30
EP1253376A3 EP1253376A3 (fr) 2005-01-19

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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CN103003633A (zh) * 2010-07-29 2013-03-27 阿尔斯通技术有限公司 点火器火花状态指示器
CN103512032A (zh) * 2012-06-26 2014-01-15 宁波市比利仕燃器科技有限公司 一种易于装配的缺氧防护装置结构
US20180119989A1 (en) * 2016-10-27 2018-05-03 Noritz Corporation Hot water apparatus
US20220049849A1 (en) * 2019-11-11 2022-02-17 Emerson Electric Co. Flame sensor assemblies and methods of replacing flame sensor assemblies

Families Citing this family (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070224558A1 (en) * 2006-03-08 2007-09-27 American Flame, Inc. Gas flow and combustion control system
US7434447B2 (en) 2006-05-17 2008-10-14 David Deng Oxygen depletion sensor
US7607426B2 (en) 2006-05-17 2009-10-27 David Deng Dual fuel heater
US7677236B2 (en) 2006-05-17 2010-03-16 David Deng Heater configured to operate with a first or second fuel
US8757139B2 (en) 2009-06-29 2014-06-24 David Deng Dual fuel heating system and air shutter
US8011920B2 (en) 2006-12-22 2011-09-06 David Deng Valve assemblies for heating devices
US8241034B2 (en) 2007-03-14 2012-08-14 Continental Appliances Inc. Fuel selection valve assemblies
US8152515B2 (en) 2007-03-15 2012-04-10 Continental Appliances Inc Fuel selectable heating devices
US7654820B2 (en) 2006-12-22 2010-02-02 David Deng Control valves for heaters and fireplace devices
US8545216B2 (en) 2006-12-22 2013-10-01 Continental Appliances, Inc. Valve assemblies for heating devices
US8403661B2 (en) 2007-03-09 2013-03-26 Coprecitec, S.L. Dual fuel heater
US8057219B1 (en) 2007-03-09 2011-11-15 Coprecitec, S.L. Dual fuel vent free gas heater
US8118590B1 (en) 2007-03-09 2012-02-21 Coprecitec, S.L. Dual fuel vent free gas heater
US7766006B1 (en) 2007-03-09 2010-08-03 Coprecitec, S.L. Dual fuel vent free gas heater
ES1067938Y (es) * 2008-05-12 2008-10-16 Coprecitec Sl Quemador de llama piloto con detector de empobrecimiento de oxigeno
US8684276B2 (en) * 2009-08-20 2014-04-01 Enerco Group, Inc. Portable catalytic heater
US9829195B2 (en) 2009-12-14 2017-11-28 David Deng Dual fuel heating source with nozzle
NZ601681A (en) * 2010-03-03 2013-10-25 Bromic Pty Ltd Wind resistant heater
EP2584258A3 (fr) 2010-06-07 2013-06-12 David Deng Système de chauffage
US10073071B2 (en) 2010-06-07 2018-09-11 David Deng Heating system
CN202328495U (zh) 2011-11-16 2012-07-11 普鲁卡姆电器（上海）有限公司 带有360度风门调节装置的多气源平衡式燃气取暖器
US9441839B2 (en) 2010-07-28 2016-09-13 David Deng Heating apparatus with fan
US8899971B2 (en) 2010-08-20 2014-12-02 Coprecitec, S.L. Dual fuel gas heater
US9739389B2 (en) 2011-04-08 2017-08-22 David Deng Heating system
US10222057B2 (en) 2011-04-08 2019-03-05 David Deng Dual fuel heater with selector valve
US8985094B2 (en) 2011-04-08 2015-03-24 David Deng Heating system
CN102506198B (zh) 2011-10-20 2013-05-22 南京普鲁卡姆电器有限公司 双气源燃气自适应主控阀
US9316401B1 (en) * 2012-03-02 2016-04-19 Henry Guste Grill fireplace unit
US9752779B2 (en) 2013-03-02 2017-09-05 David Deng Heating assembly
US9518732B2 (en) 2013-03-02 2016-12-13 David Deng Heating assembly
US10240789B2 (en) 2014-05-16 2019-03-26 David Deng Dual fuel heating assembly with reset switch
US10429074B2 (en) 2014-05-16 2019-10-01 David Deng Dual fuel heating assembly with selector switch
EP3910241B1 (fr) * 2020-05-12 2023-09-13 Otto Wilde Grillers GmbH Grill au gaz et procédé de commande associé

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5807098A (en) 1996-04-26 1998-09-15 Desa International, Inc. Gas heater with alarm system

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3963410A (en) * 1975-03-20 1976-06-15 Emerson Electric Co. Control system for domestic gas oven burners
US4245977A (en) * 1977-04-25 1981-01-20 Morese Francesco A Method and apparatus for hydrocarbon flame ignition and detection
ES523432A0 (es) * 1982-08-03 1984-06-01 Stefani & C G Pernumia Perfeccionamientos en los dispositivos de seguridad para aparatos de calentamiento por gas
US4477245A (en) * 1982-09-03 1984-10-16 The Babcock & Wilcox Company Flame monitoring safety, energy and fuel conservation system
GB2219115A (en) * 1988-05-25 1989-11-29 Baxi Partnership Ltd Burner pilot flame indicator
US5049063A (en) * 1988-12-29 1991-09-17 Toyota Jidosha Kabushiki Kaisha Combustion control apparatus for burner
GB2280023B (en) * 1993-07-09 1997-01-08 British Gas Plc Apparatus for detecting the effective ratio of air to fuel gas in a combustible mixture
US5472337A (en) * 1994-09-12 1995-12-05 Guerra; Romeo E. Method and apparatus to detect a flame
CN1212592C (zh) * 1997-02-13 2005-07-27 松下电器产业株式会社 火焰探测装置

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5807098A (en) 1996-04-26 1998-09-15 Desa International, Inc. Gas heater with alarm system

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1811230A2 (fr) * 2006-01-19 2007-07-25 Vaillant GmbH Procédé de contrôle du rapport air-combustible d'un brûleur à combustible
EP1811230A3 (fr) * 2006-01-19 2012-12-05 Vaillant GmbH Procédé de contrôle du rapport air-combustible d'un brûleur à combustible
CN103003633A (zh) * 2010-07-29 2013-03-27 阿尔斯通技术有限公司 点火器火花状态指示器
CN103003633B (zh) * 2010-07-29 2015-11-25 阿尔斯通技术有限公司 点火器火花状态指示器
CN103512032A (zh) * 2012-06-26 2014-01-15 宁波市比利仕燃器科技有限公司 一种易于装配的缺氧防护装置结构
US20180119989A1 (en) * 2016-10-27 2018-05-03 Noritz Corporation Hot water apparatus
US20220049849A1 (en) * 2019-11-11 2022-02-17 Emerson Electric Co. Flame sensor assemblies and methods of replacing flame sensor assemblies
US11644196B2 (en) * 2019-11-11 2023-05-09 Emerson Electric Co. Flame sensor assemblies and methods of replacing flame sensor assemblies

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