JP5538456B2 - Gas combustion equipment - Google Patents

Description

  The present invention relates to a gas combustion apparatus. In particular, the present invention relates to a gas burner ignition process.

  In general, a gas combustion apparatus such as a gas cooker is provided in the vicinity of a gas burner to be supplied with fuel gas and ignited by an ignition electrode and burned, and a combustion state of the gas burner. A thermocouple that is beaten and outputs a thermoelectromotive force. In this type of gas combustion device, in order to prevent combustion failure due to misfire during combustion operation, when the thermoelectromotive force of the thermocouple decreases, the supply of fuel gas to the gas burner is stopped and the user is notified of the abnormality. . In addition, even during ignition processing, in order to prevent gas leakage due to poor ignition, supply of fuel gas to the gas burner will be performed if the thermoelectromotive force of the thermocouple does not rise to a predetermined ignition detection level within a certain time from the start of ignition. The ignition process is forcibly terminated (Patent Document 1).

Japanese Patent Laid-Open No. 9-222226

  However, if air has entered the gas burner or the gas flow path of the supply pipe, incomplete combustion may occur during the ignition process, and a so-called lift phenomenon may occur in which the combustion flame extends upward. In addition, if the flame mouth that forms the combustion flame that burns the thermocouple is clogged due to boiling or the like, the combustion flame may not be formed normally. Further, in the case of a gas cooker having a grill cabinet, if the gas burner for the gas stove is ignited when the grill is used, the shape of the combustion flame may be destroyed by the exhaust from the grill cabinet. In particular, the amount of gas supplied to the gas burner at the start of ignition is usually set to a gas supply amount that forms a large flame to ensure ignitability. While the combustion flame is formed, the shape of the combustion flame tends to collapse. As a result, although the gas burner is ignited, the thermocouple is not blown by the high-temperature outer flame part of the combustion flame, and the thermoelectromotive force is unlikely to exceed the ignition detection level within a certain time, and it is determined that the ignition is poor. The gas burner may be extinguished. Therefore, the user has to repeat the ignition process, and there is a problem that the usability is bad.

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a gas combustion apparatus that prevents ignition failure and smoothly performs ignition processing of a gas burner while ensuring safety. There is to do.

The present invention comprises a gas burner that is supplied with fuel gas and is ignited and burned by ignition means;
A thermocouple disposed in the vicinity of the gas burner and outputting a thermoelectromotive force according to a heat receiving temperature;
A control unit that performs ignition detection based on whether or not the thermoelectromotive force of the thermocouple reaches a predetermined ignition detection level while igniting by the ignition means while adjusting the gas supply amount of the fuel gas to the gas burner; A gas combustion apparatus comprising:
The control unit ignites the gas burner by the ignition means while supplying fuel gas at a predetermined ignition gas amount to the gas burner at the start of ignition.
If the thermoelectromotive force of the thermocouple does not reach the ignition detection level within a predetermined time after the ignition starts, the gas supply amount to the gas burner is reduced to an ignition detection gas amount that is narrower than the ignition gas amount. ,
It is a gas combustion apparatus that determines whether or not a thermoelectromotive force of the thermocouple reaches an ignition detection level while supplying fuel gas with the ignition detection gas amount to the gas burner.

  According to the gas combustion apparatus, when the thermoelectromotive force of the thermocouple does not reach the ignition detection level within a predetermined time after the ignition starts, an ignition detection gas in which the amount of gas supplied to the gas burner is made smaller than the ignition gas amount. Therefore, if the gas burner is ignited, the size of the combustion flame formed in the flame outlet of the gas burner when the ignition detection gas amount is supplied is supplied with the ignition gas amount. It becomes smaller than that of time. Therefore, when the ignition gas amount is supplied, even if the combustion flame is lifted or the shape of the combustion flame collapses and the thermocouple is burned in the inner flame portion of the combustion flame, the gas supply amount The decrease makes it easier for the thermocouple to be beaten by the outer flame part of the combustion flame. As a result, the thermocouple's thermoelectromotive force quickly exceeds the ignition detection level when the gas burner is combusting with the amount of ignition detection gas compared to when the gas burner is combusting with the amount of ignition gas. Cheap. Therefore, even in a gas combustion apparatus in which ignition detection is performed based on whether the thermoelectromotive force reaches the ignition detection level, if the gas burner is ignited, an ignition detection error due to the shape of the combustion flame or the like can be prevented. On the other hand, after starting ignition, in a state where the combustion gas is supplied to the gas burner in the amount of ignition gas, if the thermoelectromotive force of the thermocouple becomes equal to or higher than the ignition detection level within a predetermined time, the combustion operation is continued. There is no inconvenience when the combustion flame is normally formed.

In the gas combustion apparatus, preferably,
The control unit stops the supply of the fuel gas to the gas burner when the thermoelectromotive force of the thermocouple is less than the ignition detection level when the fuel gas is supplied to the gas burner with the ignition detection gas amount. Then, when an ignition error is reported and the thermoelectromotive force of the thermocouple when the fuel gas is supplied to the gas burner with the ignition detection gas amount is equal to or higher than the ignition detection level, the fuel gas to the gas burner The gas supply amount is increased to a combustion gas amount larger than the ignition detection gas amount.

  According to the gas combustion apparatus, the thermoelectromotive force of the thermocouple is not limited even when the gas burner is burned not only with the amount of ignition gas forming a large combustion flame but also with the amount of ignition detection gas forming a small combustion flame. If it is below the ignition detection level, the supply of fuel gas to the gas burner is stopped and an ignition error is notified, so the amount of gas leakage during the ignition process is reduced and ignition failure can be reliably prevented. . On the other hand, if the gas burner is burned with the ignition detection gas amount and the thermoelectromotive force of the thermocouple is equal to or higher than the ignition detection level, the amount of fuel gas supplied to the gas burner is larger than the ignition detection gas amount. Therefore, the combustion operation can be continued in a state where a large combustion flame is formed.

In the gas combustion apparatus, preferably,
The control unit adjusts the gas supply amount so that the combustion gas amount is substantially the same as the ignition gas amount.

  According to the gas combustion device, even if the combustion flame is temporarily reduced by the amount of gas for ignition detection, after the ignition is detected, the combustion flame is formed at the same level as at the start of ignition, so the user feels less uncomfortable. .

  As described above, according to the present invention, the ignition process of the gas burner can be performed smoothly while ensuring safety and preventing ignition failure.

FIG. 1 is a schematic configuration diagram of a gas combustion apparatus according to an embodiment of the present invention. FIG. 2 is a gas circuit diagram of the gas combustion apparatus according to the embodiment of the present invention. FIG. 3 is a control flowchart showing the operation of the ignition process of the gas combustion apparatus according to the embodiment of the present invention.

  Hereinafter, the case where the gas combustion apparatus of the present invention is applied to a gas cooker will be described with reference to the drawings.

  As shown in FIG. 1, the gas cooker according to the embodiment of the present invention is provided with two gas stoves 1 and 3 on the upper surface of the gas table, and in front of the front side, inside the gas table. An open / close door is provided for putting food into and out of the provided grill 5. Further, on the left and right of the open / close door, in addition to the fire extinguishing buttons 11, 31, 51 and the thermal power adjustment knobs 12, 32, 52 having a push push mechanism (not shown) for operating the gas stoves 1, 3 and the grill 5, A buzzer 9 for notifying abnormality is provided. Moreover, the point-extinguishing buttons 11, 31, and 51 are connected to micro switches 13, 33, and 53 (see FIG. 2) that are turned on and off by pressing.

  FIG. 2 is a gas circuit diagram, and supply pipes 14, 34 and 54 branched from gas pipes for supplying fuel gas are connected to the gas burners 10 and 30 for the gas stoves 1 and 3 and the gas burner 50 for the grill 5, respectively. Has been. In addition, since the ignition processing method of this Embodiment is applied to the gas stoves 1 and 3, the structure of the gas stoves 1 and 3 is mainly demonstrated concretely below.

  The supply pipes 14 and 34 connected to the gas burners 10 and 30 for the gas stoves 1 and 3 include main valves 15 and 35 that are opened and closed by pressing the fire extinguishing buttons 11 and 31, and when the ignition to the gas burners 10 and 30 is started. Safety valves 16 and 36 composed of electromagnetic valves that are opened, and flow rate control valves 17 and 37 composed of electromagnetic valves that adjust the amount of fuel gas supplied to the gas burners 10 and 30 are arranged. The supply pipes 14 and 34 are formed with bypass passages 18 and 38 that branch before and after the flow control valves 17 and 37 and are parallel to the flow control valves 17 and 37. 19 and 39 are provided. Therefore, when the flow rate control valves 17 and 37 are closed, the fuel gas is supplied to the gas burners 10 and 30 only through the bypass passages 18 and 38, so that the gas supply amount decreases. On the other hand, when the flow control valves 17 and 37 are opened, the gas supply amount increases. As described above, the safety valves 16 and 36 and the flow rate control valves 17 and 37 are electromagnetic valves, and their opening degrees are adjusted according to a signal from the control unit 7 described later.

  In the vicinity of the gas burners 10 and 30, there are ignition electrodes 20 and 40 that perform spark discharge, and thermocouples 21 and 41 that are burned by the combustion flame and output thermoelectromotive force, and a flame opening (not shown) of the gas burners 10 and 30. It is arranged to face. The ignition electrodes 20 and 40 are subjected to spark discharge when the control unit 7 controls the energization of the sparker SP, whereby the gas burners 10 and 30 are ignited. These ignition electrodes 20 and 40 and the sparker SP correspond to ignition means.

  Although not shown, the control unit 7 includes a microcomputer, and opens and closes a sparker control unit for controlling energization to the sparker SP and safety valves 16 and 36 in accordance with the operation of the fire extinguishing buttons 11 and 31 as functional constituent means. Safety valve drive unit, control valve drive unit for opening and closing the flow rate control valves 17, 37, ignition detection unit for determining whether the thermoelectromotive force of the thermocouples 21, 41 is equal to or higher than a predetermined ignition detection level, and performing predetermined notification In addition to a buzzer drive unit for energizing and driving the buzzer 9 according to instructions from the microcomputer, a timer and a combustion operation control unit for performing a predetermined combustion operation are provided. Safety valves 16 and 36, flow rate control valves 17 and 37, ignition electrodes 20, 40, thermocouples 21 and 41, and microswitches 13 and 33 that are turned on and off in conjunction with the operation of the fire extinguishing buttons 11 and 31, and the like.

  Next, the operation control of the ignition process in the gas cooker of the present embodiment will be specifically described with reference to the control flowchart of FIG. In addition, since the operation control of the ignition process of the gas stoves 1 and 3 is the same, the gas stove 1 will be described below as an example.

  When the user performs an ignition operation by pressing the fire extinguishing button 11 (ST1), the main valve 15 is opened and the micro switch 13 is turned on to start energization from the power source. When the supply of power to the microcomputer is started, the control unit 7 starts a timer, starts supplying power to the sparker SP, and sends a signal so that an adsorption current flows to the safety valve 16 and the flow rate control valve 17. These are held open. As a result, the amount of ignition gas that becomes a combustion flame of a large fire is supplied to the gas burner 10, the ignition electrode 20 is sparked, and ignition of the gas burner 10 is started.

  Next, whether or not the thermocouple 21 is burned by the combustion flame of the gas burner 10 and the thermoelectromotive force output from the thermocouple 21 is equal to or higher than a predetermined ignition detection level (for example, 3.5 V ± 0.5 mV). Is started (ST2).

  If the thermoelectromotive force of the thermocouple 21 becomes equal to or higher than the ignition detection level within a predetermined elapsed time (for example, 7 seconds) from the start of ignition of the gas burner 10 (Yes in ST2, No in ST3), the control unit 7 Then, it is determined that the ignition of the gas burner 10 is completed, the power supply to the sparker SP is stopped, and the combustion operation is continued (ST8 to ST9).

  On the other hand, even if fuel gas is supplied to the gas burner 10 in the amount of ignition gas, when the thermoelectromotive force of the thermocouple 21 is less than the ignition detection level for a predetermined elapsed time from the start of ignition (in ST2, No, in ST3, Yes), the control unit 7 stops the adsorption current to the flow control valve 17 and closes the flow control valve 17 (ST4). As a result, the gas supply amount is reduced, and the fuel gas is supplied to the gas burner 10 only through the orifice 19 of the bypass 18, so that an ignition detection gas amount that becomes a combustion flame of the medium flame is supplied to the gas burner 10. .

  After the gas supply amount is changed from the ignition gas amount to the ignition detection gas amount, the thermoelectromotive force of the thermocouple 21 exceeds the ignition detection level until a predetermined elapsed time (for example, 10 seconds) has elapsed from the start of ignition. The determination of whether or not will continue (ST5 to ST6). If the thermoelectromotive force of the thermocouple 21 becomes equal to or higher than the ignition detection level within a predetermined elapsed time (Yes in ST5, No in ST6), the control unit 7 determines that the ignition of the gas burner 10 is completed. Then, the power supply to the sparker SP is stopped and the adsorption current is again applied to the flow rate control valve 17 to open the flow rate control valve 17 (ST7). As a result, the gas supply amount is increased to a combustion gas amount that is larger than the ignition detection gas amount (in this embodiment, the same gas amount as the ignition gas amount), and the combustion operation is continued (ST9). .

  On the other hand, even if the gas supply amount is changed to the ignition detection gas amount and the predetermined elapsed time has elapsed, the thermoelectromotive force of the thermocouple 21 is below the ignition detection level (in ST5, No, in ST6, Yes), the control unit 7 stops power supply to the sparker SP, stops the adsorption current to the safety valve 16 and closes it, and notifies the ignition error from the buzzer 9 (ST10). When the thermoelectromotive force of the thermocouple 21 does not rise to the ignition detection level due to the lift of the combustion flame or the like, the gas burner 10 is in an ignited state, so the thermocouple 21 has been beaten by the combustion flame from the start of ignition. Is in a state. Therefore, after changing the gas supply amount from the ignition gas amount to the ignition detection gas amount, the thermoelectromotive force should rise to the ignition detection level at an early stage, so that the fuel gas is supplied to the gas burner 10 with the ignition gas amount. It is possible to determine the ignition detection in a time shorter than the time for determining the ignition detection when being supplied.

  As described above, according to the gas combustion apparatus of the present embodiment, even if the combustion gas is supplied to the gas burner with the amount of ignition gas that forms a large combustion flame until a predetermined time has elapsed from the start of ignition, When the thermoelectromotive force does not rise to the predetermined ignition detection level, the gas supply amount to the gas burner is reduced from the ignition gas amount to the ignition detection gas amount, so if the gas burner is ignited, a small combustion flame is formed. The Therefore, in the state where the ignition gas amount is supplied, even if the thermocouple is burned in the inner flame portion of the combustion flame due to the lift of the combustion flame or the collapse of the shape of the combustion flame, the gas supply amount is By reducing the amount of ignition detection gas, the combustion flame is reduced, and the thermocouple is easily burned at the outer flame portion of the combustion flame. As a result, since the thermoelectromotive force of the thermocouple rises early to the ignition detection level, even if incomplete combustion or the like has occurred, it is possible to reliably detect ignition in a short time.

  In addition, in this embodiment, when the ignition detection is performed with the amount of ignition detection gas, the gas supply amount is increased to a combustion gas amount comparable to the ignition gas amount, so the combustion flame is supplied with the ignition gas amount. It returns to the same size as it was. Therefore, even if the user reduces the combustion flame for a short time, the user feels uncomfortable.

  Also, until a predetermined time has elapsed from the start of ignition, if the ignition gas amount is supplied to the gas burner, and a thermal electromotive force greater than the ignition detection level is obtained during that time, the combustion operation is performed without reducing the gas supply amount. Since it is continued, user convenience is good.

  On the other hand, if ignition is performed by reducing the gas supply amount to the ignition detection gas amount, if the thermoelectromotive force of the thermocouple does not increase, a small combustion flame is formed even if the ignition gas amount is large. Since the thermoelectromotive force of the thermocouple does not increase even with the amount of ignition detection gas to be determined, it is determined that an ignition failure has occurred, and the ignition process can be terminated early. Thereby, the leakage of raw gas is reduced and high safety can be secured.

  In addition, although the case where this invention was applied to the ignition process of the gas burner for gas stoves was demonstrated in the said embodiment, you may apply to the gas burner for grills. Moreover, you may apply to gas combustion apparatuses, such as a gas hot air heater and a gas water heater, which use gas burners other than a gas cooker.

10, 30 Gas burner 21, 41 Thermocouple 20, 40 Ignition electrode 7 Control unit SP Sparker

Claims (3)

A gas burner supplied with fuel gas and ignited and burned by ignition means;
A thermocouple disposed in the vicinity of the gas burner and outputting a thermoelectromotive force according to a heat receiving temperature;
A control unit that performs ignition detection based on whether or not the thermoelectromotive force of the thermocouple reaches a predetermined ignition detection level while igniting by the ignition means while adjusting the gas supply amount of the fuel gas to the gas burner; A gas combustion apparatus comprising:
The control unit ignites the gas burner by the ignition means while supplying fuel gas at a predetermined ignition gas amount to the gas burner at the start of ignition.
If the thermoelectromotive force of the thermocouple does not reach the ignition detection level within a predetermined time after the ignition starts, the gas supply amount to the gas burner is reduced to an ignition detection gas amount that is narrower than the ignition gas amount. ,
A gas combustion apparatus that determines whether or not a thermoelectromotive force of the thermocouple reaches an ignition detection level while supplying fuel gas with the ignition detection gas amount to the gas burner. The gas combustion apparatus according to claim 1, wherein
The control unit stops the supply of the fuel gas to the gas burner when the thermoelectromotive force of the thermocouple is less than the ignition detection level when the fuel gas is supplied to the gas burner with the ignition detection gas amount. Then, when an ignition error is reported and the thermoelectromotive force of the thermocouple when the fuel gas is supplied to the gas burner with the ignition detection gas amount is equal to or higher than the ignition detection level, the fuel gas to the gas burner A gas combustion apparatus that increases the gas supply amount of the gas to a combustion gas amount larger than the ignition detection gas amount. The gas combustion apparatus according to claim 2,
The control unit is a gas combustion apparatus that adjusts a gas supply amount so that the amount of combustion gas is substantially equal to the amount of ignition gas.

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