JP2010014336A - Gas cooking stove - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To promptly detect valve opening failure when the valve opening failure occurs in a main valve 3 to solve a problem on the so-called valve opening failure that the main valve 3 is kept in an opened state caused by catching of dust and the like, because the supply of a gas to a gas burner in such a state that each gas burner is not operated, is cut off only by a solenoid safety valve 5 when the main valve 3 has the valve opening failure, the gas leakage from the gas burner cannot be stopped when the valve opening failure further occurs in the solenoid safety valve as the cutoff of the gas is performed in one stage only by the solenoid safety valve. <P>SOLUTION: In a case when a fire extinguishing operation is performed to the ignited gas burner in a state only one of the plurality of gas burners is ignited, the main valve 3 is closed first, and then the solenoid safety valve 3 is closed after the lapse of a measurement time to confirm the fire extinction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas stove provided with a plurality of gas burners to which gas is supplied through one main valve.

  The gas stove is provided with a plurality of gas burners on the upper surface, and in the case where a grill cabinet that can be taken in and out from the front is provided, a gas burner for grill is attached in the grill cabinet. In such a gas stove, gas is supplied to each burner from a gas supply source via a main valve. Since it is necessary to individually supply gas to each gas burner, gas branch pipes that supply gas to each burner downstream of the main valve are connected in parallel to each other. And the thermal power control unit for adjusting the thermal power by opening and closing the gas branch pipe to each gas burner and increasing / decreasing the amount of gas to supply is provided in each gas branch pipe (for example, refer patent document 1). .

This thermal power control unit is provided with an electromagnetic safety valve in series with a thermal power control unit that adjusts the thermal power. This electromagnetic safety valve is held open in an ignition state by the control unit. When a fire extinguishing operation is performed, the control unit closes the electromagnetic safety valve and stops the supply of gas to the gas burner.
Japanese Patent Laying-Open No. 2006-189231 (FIG. 2)

  With the above configuration, a so-called valve opening failure may occur in which the valve body is fixed and cannot be closed while the original valve remains open due to dust bites or the like. When a valve opening failure occurs in the main valve, only the electromagnetic safety valve shuts off the gas supply to the gas burner when each gas burner extinguishes. If the gas is shut off in one stage with only the electromagnetic safety valve in this way, the leakage of gas from the gas burner cannot be stopped if the electromagnetic safety valve subsequently fails to open. If a failure occurs, it must be repaired promptly.

  Then, this invention makes it a subject to provide the gas stove which can detect rapidly that the valve opening failure has arisen in the main valve in view of said problem.

  In order to solve the above-described problems, a gas stove according to the present invention includes a plurality of gas burners connected in parallel to a gas supply source via a single electromagnetic open / close type main valve, and supplies gas to each gas burner. A fire extinguishing means for stopping the supply of gas to the gas burner by closing at least the gas branch pipe from the open state by a signal from the control unit is provided in each gas branch pipe, and flame is detected in each burner And a predetermined measurement time for determining from the output signal from the flame detection sensor that the fire has been extinguished since the supply of gas to the gas burner is stopped. In a gas stove, with only one of the plurality of gas burners ignited, extinguishing the fired gas burner When the operation is performed, the control unit first outputs a valve closing signal to the original valve and determines that the gas burner is not extinguished when the measurement time has elapsed from the time when the valve closing signal is output. Then, a valve opening failure determination means for determining that a valve opening failure has occurred in the original valve is provided.

  If there is no valve opening failure in the main valve and the main valve closes normally, the gas burner extinguishes when the main valve closes. Therefore, if the measurement time elapses from the time when the valve closing signal is output to the main valve, the control unit can detect that the main valve has closed normally because the gas burner has extinguished. On the other hand, if the main valve did not close due to a valve opening failure, the gas valve burner was not extinguished even after the measurement time had elapsed, so the valve could not be closed because the gas burner was not extinguished. Can be detected.

  Each gas burner can shut off the gas with the fire extinguishing means, so even if the main valve fails to open, gas does not leak immediately from the gas burner, but the measurement time from when the valve closing signal is output to the main valve When the control unit cannot confirm the fire extinguishing of the gas burner at the time when it has elapsed, it is provided with a function stop means for ensuring that all the gas branch pipes are closed by the fire extinguishing means, and thereafter prohibiting all opening of the gas branch pipes by the fire extinguishing means It is desirable to prohibit the use of gas stoves until the main valve is repaired.

  As is apparent from the above description, the present invention uses only one gas burner in a state where the gas stove is normally used, and when the gas burner is extinguished, the main valve is not open. Since the presence / absence is checked, even if the main valve has failed to open, it can be immediately detected.

  With reference to FIG. 1, 1 is an example of a gas stove according to the present invention. The gas stove 1 is provided with two large burners 11 and a middle burner 12 on the upper surface, and a gas burner for grilling (a pair of an upper fire burner and a lower fire burner) in a grill cabinet 13 that can be taken in and out from the front. Is provided. In addition to the power switch 10, dials 11 a, 12 a, and 13 a that perform point fire extinguishing and heating power adjustment of each burner are provided on the front surface. For example, when the middle burner 12 is ignited, the middle burner 12 is ignited by pressing the dial 12a to perform the ignition operation. Then, the heating power is adjusted by turning the dial 12a left and right, and the middle burner 12 is extinguished by pressing the dial 12a again.

  As shown in FIG. 2, each of the burners is connected to a large burner 11, an intermediate burner 12, and branch pipes 31 that branch the gas to both burners of the grill 13 through a main valve 3 that is an electromagnetic on-off valve. It is provided in parallel. Each branch pipe 31 is provided with a thermal power adjustment unit 2.

  The thermal power control unit 2 includes a thermal power control unit 4 that adjusts the opening degree by a motor driven by a signal from the control unit 6 and an electromagnetic safety valve 5 provided in series upstream of the thermal power control unit 4. Has been. The electromagnetic safety valve 5 is opened by a heating power adjusting motor, but is held open by the electric power supplied from the control unit 6 during ignition of the gas burner.

  Each burner is provided with a thermocouple 15 that is a flame sensor for detecting ignition in an ignition state. The output signals from these thermocouples 15 are individually input to the control unit 6.

  Each burner is provided with a spark plug 16 as an ignition means. The operation of each of these spark plugs 16 is controlled by the control unit 6, but even when any one of the burners is ignited, all the spark plugs 16 are actuated to generate a spark discharge with each burner. It is configured.

  Among these gas burners, when a plurality of gas burners are used, the original valve remains open, and if any one of the gas burners being ignited is extinguished, The gas burner is extinguished by closing the electromagnetic safety valve 5 provided for the fire extinguishing operation. Since the thermocouple 15 is continuously heated by the flame during ignition, the thermoelectromotive force as an output value is maintained at a high level.

  Referring to FIG. 3, when the gas burner is extinguished, the flame that has heated thermocouple 15 disappears, so that the output thermoelectromotive force rapidly decreases. The decrease in thermoelectromotive force is shown in curve R. The thermocouple 15 has a heat capacity. When the fire is extinguished, the thermoelectromotive force rapidly decreases, but does not instantaneously decrease to the room temperature level.

  A predetermined threshold value V is set in advance, and when the thermoelectromotive force output from the thermocouple 15 falls below the threshold value V until the predetermined measurement time t elapses from the moment when the fire is extinguished, the control unit 6 Is set to judge.

  Now, for example, if only the middle burner 12 is in use and all the other burners are extinguished, and a fire extinguishing operation is performed to extinguish the middle burner 12, if another gas burner is in use, the electromagnetic The safety valve 5 is closed. In this case, the main valve 3 is closed first. Even if the main valve 3 is closed, the middle burner 12 is extinguished, so the thermoelectromotive force from the thermocouple 15 attached to the middle burner 12 decreases as shown by a curve R in FIG. The electromagnetic safety valve 5 is closed after the measurement time t has passed and the fire extinguishing of the middle burner 12 is confirmed.

  Here, if a valve opening failure has occurred in the main valve 3, the control unit 6 opens the main valve 3 because the thermoelectromotive force continues to be output at a high level even after the measurement time t has elapsed. Judge that a failure has occurred. Even if a valve opening failure has occurred in the main valve 3, the electromagnetic burner 12 is closed when the measurement time t has elapsed, so the middle burner 12 is safely extinguished.

  When the control unit 6 determines that a valve opening failure has occurred in the main valve 3, the use of the gas stove 1 is prohibited thereafter. That is, the motor of the thermal power control unit 2 is not operated even if any gas burner is ignited. Then, it is desirable to generate an error display or a warning sound to notify that the valve opening failure has occurred in the main valve 3 and to prompt repair.

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention.

The figure which shows the structure of one embodiment of this invention Block diagram showing piping status in gas stove Diagram showing changes in thermoelectromotive force

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas cooker 2 Thermal power control unit 3 Main valve 4 Thermal power control part 5 Electromagnetic safety valve 6 Control unit 15 Thermocouple

Claims (2)

  Provided with a plurality of gas burners connected in parallel to the gas supply source through one electromagnetic open / close type main valve, provided with gas branch pipes for supplying gas to each gas burner, and at least the gas branch by the signal from the control unit Fire extinguishing means for stopping the supply of gas to the gas burner by closing the pipe from the open state is provided in each gas branch pipe, and a flame detection sensor for detecting flame is provided in each burner, and the control unit Is a gas stove in which a predetermined measurement time for determining from the output signal from the flame detection sensor that the fire has been extinguished from the time when supply of gas to the gas burner is stopped is any one of the plurality of gas burners. When only one unit is ignited, when the fire extinguishing operation is performed with respect to the ignited gas burner, the control unit first controls the main valve. If the gas burner is not extinguished when the measured time has elapsed from the time when the valve closing signal is output, it is determined that a valve opening failure has occurred in the main valve. A gas stove comprising a judging means.   When the valve opening failure determination means determines that a valve opening failure has occurred, the fire extinguishing means secures the closing of all the gas branch pipes, and thereafter the function stop means for prohibiting all the gas branch pipes from being opened by the fire extinguishing means. The gas stove according to claim 1, further comprising a gas stove.

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