JP5484408B2 - Gas stove - Google Patents

Description

  The present invention relates to a gas stove provided with an electromagnetic valve for switching between supply and shutoff of fuel gas to a burner.

  2. Description of the Related Art Conventionally, a gas stove solenoid valve drive circuit has a configuration in which a holding coil of a solenoid valve and a power source are connected via two switching elements (transistors) (for example, Patent Documents). 1). By adopting this configuration, even if one of the two switching elements has an ON failure (a failure in which the switching element is maintained in a conductive state regardless of the voltage level of the control input), no ON failure has occurred. The supply of fuel gas to the burner is cut off by controlling the other switching elements to be cut off.

  In the gas stove described in Patent Document 1, when the ignition operation of the burner is performed, control is performed so that two switching elements connected in series with the holding coil of the electromagnetic valve are alternately conducted, and 2 The presence or absence of a failure of each switching element is detected, and when a failure of the switching element is detected, a failure notification by a buzzer is performed.

Japanese Patent Laid-Open No. 6-17963

  The gas stove described in Patent Document 1 includes a plurality of burners, and connects the solenoid valve driving circuit for each burner between the holding coil of each solenoid valve and the power supply via two switching elements. It is configured. When the ignition operation of any one of the burners is performed by the user, the drive circuit of the solenoid valve of the burner that has been ignited is detected for the presence or absence of failure of the two switching elements. The burner is ignited as a condition.

  In this case, with respect to the burner that has been ignited, it has been confirmed that the corresponding solenoid valve drive circuit and its operation check circuit operate normally. On the other hand, it has not been confirmed that the corresponding solenoid valve drive circuit and its operation check circuit operate normally for burners that have not been ignited.

  Therefore, for a burner that is used infrequently, even if a failure occurs in the corresponding solenoid valve drive circuit or its operation confirmation circuit, this state may be left and the discovery of the failure may be delayed. Thus, it is not preferable that the gas stove be continuously used in a state where the drive circuit of the solenoid valve corresponding to any one of the burners or the operation confirmation circuit thereof has failed.

  The present invention has been made in view of the above-described background, and when a failure occurs in a drive circuit of an electromagnetic valve corresponding to any one of the burners or a circuit for confirming the operation thereof, a gas stove that promptly notifies the failure is provided. The purpose is to provide.

  The present invention has been made in order to achieve the above object, and is an ignition operation in which a predetermined number of burners of two or more, a power source, and each of the burners are individually provided to perform the ignition operation of the corresponding burner. And a fuel gas supply path of the corresponding burner, which is provided individually for each burner, and is opened from the closed state according to the ignition operation of the ignition operation unit for the corresponding burner. And switching between the pair of output terminals of the power source to the pair of connection terminals via a plurality of switching elements. A solenoid valve drive circuit having at least the predetermined number of circuits, and holding coils of the respective solenoid valves assigned to any one of the predetermined number or more of connection terminals, and operation of each ignition operation unit Operation status to detect status When the intelligent unit, the inter-terminal voltage detection unit for detecting the voltage between the connection terminals, and the operation state detection unit detect that any of the ignition operation units has been ignited, the ignition Voltage between the connection terminals of the connection circuit detected by the inter-terminal voltage detection unit by controlling conduction of all of the plurality of switching elements of the connection circuit for the burner corresponding to the operated ignition operation unit A failure detection unit that detects the presence or absence of a failure of the connection circuit, and a failure notification when the failure of the connection circuit is detected by the failure detection unit. The present invention relates to an improvement of a gas stove provided with a failure notification unit.

  The failure detection unit corresponds to the ignition operation unit that has performed the ignition operation when the operation state detection unit detects that any ignition operation of the ignition operation unit has been performed. Also for the connection circuit for the burner other than the burner, the conduction between all the plurality of switching elements is controlled, and the voltage between the connection terminals of the connection circuit detected by the inter-terminal voltage detection unit is A failure of the connection circuit is detected by determining whether or not the voltage is equal to or higher than a predetermined voltage (first invention).

  In the first aspect of the invention, the solenoid valve that opens and closes the fuel gas supply path of each burner does not open unless the ignition operation section is ignited. Therefore, the solenoid valve that has not been ignited by the ignition operation unit does not open even when all of the plurality of switching elements of the connection circuit to which the holding coil is connected are in a conductive state.

  Therefore, the failure detection unit detects the presence or absence of a failure in the connection circuit for the burner that has been ignited by the ignition operation unit, and the connection circuit for the burner that has not been ignited by the ignition operation unit. In addition, all the plurality of switching elements are subjected to conduction control, and the inter-terminal voltage detection unit determines whether the voltage between the connection terminals is equal to or higher than the predetermined voltage. As a result, it is detected whether or not there is an OFF failure of the plurality of switching elements (a failure in which the switching elements are maintained in the shut-off state regardless of the voltage level of the control input) while maintaining the solenoid valve in the closed state. be able to.

  When the failure detection unit detects a failure in the connection circuit, the failure notification unit performs a failure notification. Therefore, a configuration for confirming the operation of the connection circuit when the connection circuit of the solenoid valve drive circuit corresponding to any one of the burners is broken or the connection circuit can operate normally. The failure notification can be promptly performed when the failure detection unit erroneously detects that the connection circuit has failed due to a failure of the inter-terminal voltage detection unit.

  In the first aspect of the present invention, the electromagnetic valve driving circuit further includes a coil connection information holding unit that holds coil connection information indicating whether or not the holding coil of the electromagnetic valve is connected to each of the connection circuits, and the failure notification The unit recognizes the connection circuit to which the holding coil of the solenoid valve is connected based on the coil connection information, and sets only the connection circuit to which the holding coil of the solenoid valve is connected as a target of the failure notification. The connection circuit to which the holding coil of the solenoid valve is not connected is not subject to the failure notification (second invention).

  According to the second invention, when the solenoid valve drive circuit is commonly used among gas stoves having different numbers of burners, the failure notification unit is configured to store the coil held in the coil connection information holding unit. Based on the connection information, the connection circuit to which the holding coil of the electromagnetic valve is connected and the connection circuit to which the holding coil of the electromagnetic valve is not connected can be identified. Therefore, the failure notification unit targets only the connection circuit that is not connected to the holding coil of the solenoid valve as a target of the failure notification, and the failure circuit is configured to detect the failure of the connection circuit that is not connected to the holding coil of the solenoid valve. It can be excluded from notification targets.

  In the second invention, the failure notification unit reads out the coil connection information from the coil connection information holding unit in parallel with the detection of the presence / absence of failure of all the connection circuits by the failure detection unit. The holding coil of the electromagnetic valve at the time when the detection of the presence / absence of a failure in all the connection circuits by the failure detection unit and the reading of the coil connection information from the coil connection information holding unit are completed. It is determined whether or not a failure is detected by the failure detection unit for the connection circuit to which is connected, and the failure notification is performed according to the determination (third invention).

  According to the third invention, after reading the coil connection information from the coil connection information holding unit and recognizing the connection circuit to which the holding coil of the electromagnetic valve is connected, the holding coil of the electromagnetic valve is connected. About the said connection circuit, time until failure alert | report is made can be shortened rather than the case where the presence or absence of the failure is detected by the said failure detection part.

The block diagram of a gas stove. The block diagram of a solenoid valve drive circuit. The 1st flowchart of a process when the ignition operation of a burner was made. The 2nd flowchart of a process when the ignition operation of a burner was made. Timing chart when burner ignition operation is performed.

  An embodiment of the present invention will be described with reference to FIGS. Referring to FIG. 1, a gas stove 1 according to this embodiment includes an H burner (large fire burner) 10, an M burner (medium burner) 20, and an S burner (small fire burner) 30 on the top surface. A G burner (grill burner) 40 is provided in the cabinet. The H burner 10, the M burner 20, the S burner 30, and the G burner 40 correspond to the burner of the present invention.

  Further, the gas stove 1 includes a controller 50 that controls the operation of the gas stove 1, a power source 51 (battery or the like) that supplies power to the controller 50, and a display unit 52 that displays the operating state of the gas stove 1. It has.

  On the front side of the gas stove 1 are an H burner point extinguishing button 14 for instructing ignition and extinguishing of the H burner 10, an M burner point extinguishing button 24 for instructing ignition and extinguishing of the M burner 20, and an S burner 30. Are provided with an S burner point extinguishing button 34 for instructing ignition and extinguishing of the G burner, and a G burner point extinguishing button 44 for instructing ignition and extinguishing of the G burner 40. The H burner point fire extinguishing button 14, the M burner point fire extinguishing button 24, the S burner point fire extinguishing button 34, and the G burner point fire extinguishing button 44 include the function of the ignition operation unit of the present invention.

  For the H burner 10, an H burner temperature sensor 11 that detects the temperature of the food, an H burner thermocouple 12 that detects the combustion state of the H burner 10, and an H burner ignition plug for igniting the H burner 10. 13 is provided. Further, the gas supply pipe 5 is provided with an H burner source gas valve 16 and an H burner electromagnetic valve 15 for switching between supply and cutoff of fuel gas to the H burner 10.

  The H burner source gas valve 16 and the H burner solenoid valve 15 have, for example, a push-push mechanism having a configuration of an electromagnetic safety valve described in Japanese Patent Application Laid-Open No. 2010-139189. The valve opens in conjunction. That is, in the state where the H burner point fire extinguishing button 14 is in the start position where the pressing operation (ignition operation) is not performed, both the H burner source gas valve 16 and the H burner electromagnetic valve 15 are closed, and the H burner 10 The fuel gas supply is shut off.

  When the H burner point extinguishing button 14 is pressed (ignition operation), the H burner source gas valve 16 is first opened, and then the H burner point extinguishing button 14 is further pushed to the ignition position. The electromagnetic valve 15 opens. At this time, the H burner micro switch 17 is switched from OFF (open state) to ON (closed state), and power supply from the power source 51 to the controller 50 is started.

  When the H burner point fire extinguishing button 14 is pushed to the ignition position, the holding coil of the H burner electromagnetic valve 15 is energized, and the H burner electromagnetic valve 15 is held in the open state. As a result, the fuel gas is supplied to the H burner 10.

  When the H burner point fire extinguishing button 14 is further pushed from the ignition position to the end position and then released, the H burner point fire extinguishing button 14 is locked at the holding position before the start end position. In the holding position, the H burner source gas valve 16 is mechanically held open, and the H burner solenoid valve 15 is held open by energizing the holding coil.

  For the M burner 20, an M burner temperature sensor 21 that detects the temperature of the food, an M burner thermocouple 22 that detects the combustion state of the M burner 20, and an M burner ignition plug for igniting the M burner 20. 23. Further, the gas supply pipe 5 is provided with an M burner source gas valve 26 and an M burner electromagnetic valve 25 for switching between supply and cutoff of the fuel gas to the M burner 20.

  The configurations of the M burner source gas valve 26, the M burner electromagnetic valve 25, and the M burner micro switch 27 are the same as the configurations of the H burner source gas valve 16, the H burner electromagnetic valve 15, and the H burner micro switch 17.

  For the S burner 10, an S burner temperature sensor 31 for detecting the temperature of the cooked product, an S burner thermocouple 32 for detecting the combustion state of the S burner 30, and an S burner ignition plug for igniting the S burner 30. 33. Further, the gas supply pipe 5 is provided with an S burner source gas valve 36 and an S burner electromagnetic valve 35 for switching between supply and cutoff of fuel gas to the S burner 30.

  The configurations of the S burner source gas valve 36, the S burner solenoid valve 35, and the S burner micro switch 37 are the same as the configurations of the H burner source gas valve 16, the H burner solenoid valve 15, and the H burner micro switch 17.

  For the G burner 40, a G burner thermocouple 41 for detecting the combustion state of the G burner 40 and a G burner ignition electrode 42 for igniting the G burner 40 are provided. Further, the gas supply pipe 5 is provided with a G burner source gas valve 46 and a G burner electromagnetic valve 45 for switching between supply and cutoff of the fuel gas to the G burner 40.

  The configurations of the G burner source gas valve 46, the G burner electromagnetic valve 45, and the G burner micro switch 47 are the same as the configurations of the H burner source gas valve 16, the H burner electromagnetic valve 15, and the H burner micro switch 17.

  Next, the controller 50 is an electronic unit including a microcomputer 60, a memory (not shown), and the like, and holds the H burner solenoid valve 15, the M burner solenoid valve 25, the S burner solenoid valve 35, and the G burner solenoid valve 45. An electromagnetic valve drive circuit 70 for controlling energization to the coil and a model setting switch 55 for inputting a model code of a gas stove in which the controller 50 is mounted are provided.

  The model setting switch 55 corresponds to the connection information holding unit of the present invention, and the model code corresponds to the coil connection information of the present invention.

  The solenoid valve drive circuit 70 is connected to the holding coil of the H burner solenoid valve 15 by a pair of connection terminals 80a and 80b. Similarly, the pair of connection terminals 81a and 81b are connected to the holding coil of the M burner electromagnetic valve 25, the pair of connection terminals 82a and 82b are connected to the holding coil of the S burner electromagnetic valve 35, and the pair of connection terminals 83a and 83b. Is connected to the holding coil of the G burner solenoid valve 45.

  The controller 50 includes an ON / OFF signal for the H burner microswitch 17, a temperature detection signal for the H burner temperature sensor 11, a combustion state detection signal for the H burner thermocouple 12, an ON / OFF signal for the M burner microswitch 27, and an M burner. Temperature detection signal of temperature sensor 21, combustion state detection signal of M burner thermocouple 22, ON / OFF signal of S burner micro switch 37, temperature detection signal of S burner temperature sensor 31, combustion state detection signal of S burner thermocouple 32 The ON / OFF signal of the G burner micro switch 47 and the combustion state detection signal of the G burner thermocouple 41 are input.

  The microcomputer 60 executes the control program for the gas stove 1 held in the memory, thereby causing the H burner point fire button 14, the M burner point fire button 24, the S burner point fire button 34, and the G burner point fire button. 44, an operation state detection unit 61 that detects the operation state of 44, an inter-terminal voltage detection unit 62 that detects an inter-terminal voltage of each of the connection terminals 80a, 80b, 81a, 81b, 82a, 82b, 83a, 83b, and an electromagnetic valve drive A failure detection unit 63 that detects the presence or absence of a failure in the connection circuit of the circuit 70; a failure notification unit 64 that performs failure notification when the failure detection unit 63 detects a failure in the connection circuit of the solenoid valve drive circuit 70; It functions as a combustion control unit 65 that executes the combustion operation of each burner.

  Next, referring to FIG. 2, the solenoid valve drive circuit 70 includes a PNP-type upper transistor 71 and lower transistors 72 to 75 whose control terminals (base terminals) are connected to output ports Po1 to Po5 of the microcomputer 60. I have. The upper transistor 71 is connected between the Vcc terminal of the power source 51 (see FIG. 1) and the lower transistors 72 to 75, and is in a cut-off state and a conductive state according to the level (High / Low) of the control input Uctr from the output port Po1. Controlled.

  The lower transistor 72 (hereinafter also referred to as the H burner lower transistor 72) is connected between the upper transistor 71 and the resistor 76 connected to the connection terminal 80a, and the level (High / High) of the control input Hctr from the output port Po2. In response to Low), it is controlled to the cut-off state and conductive state. The holding coil 15a of the H burner 15 connected between the connection terminals 80a and 80b is connected to the output terminal (Vcc terminal, GND terminal) of the power source 51 through the upper transistor 71 and the H burner lower transistor 72.

  The lower transistor 73 (hereinafter also referred to as M burner lower transistor 73) is connected between the upper transistor 71 and the resistor 77 connected to the connection terminal 81a, and the level (High / Low) of the control input Mctr from the output port Po3. In response to Low), it is controlled to the cut-off state and conductive state. The holding coil 25a of the M burner solenoid valve 25 connected between the connection terminals 81a and 81b is connected between the output terminals (Vcc terminal and GND terminal) of the power source 51 via the upper transistor 71 and the M burner lower transistor 73. Yes.

  The lower transistor 74 (hereinafter also referred to as the S burner lower transistor 74) is connected between the upper transistor 71 and the resistor 78 connected to the connection terminal 82a, and the level (High) of the control input Sctr from the output port Po4. / Low) is controlled to a cut-off state and a conductive state. The holding coil 35a of the S burner solenoid valve 35 connected between the connection terminals 82a and 82b is connected between the output terminals (Vcc terminal and GND terminal) of the power source 51 via the upper transistor 71 and the S burner lower transistor 74. ing.

  The lower transistor 75 (hereinafter also referred to as a G burner lower transistor 75) is connected between the upper transistor 71 and the resistor 79 connected to the connection terminal 83a, and is connected to the control input Gctr (High / Low) from the output port Po5. In accordance with the control, the cut-off state and the conduction state are controlled. The holding coil 45a of the G burner solenoid valve 45 connected between the connection terminals 83a and 83b is connected between the output terminals (Vcc terminal and GND terminal) of the power source 51 via the upper transistor 71 and the G burner lower transistor 75. ing.

  The connection circuit of the present invention is constituted by a path from the Vcc terminal to the connection terminal 80a via the upper transistor 71 and the H burner lower transistor 72 and the resistor 76, and a path from the GND terminal to the connection terminal 80b. . Similarly, the connection circuit of the present invention is constituted by the path from the Vcc terminal to the connection terminal 81a via the upper transistor 71 and the M burner lower transistor 73 and the resistor 77 and the path from the GND terminal to the connection terminal 81b. Yes.

  Further, the connection circuit of the present invention is constituted by the path from the Vcc terminal to the connection terminal 82a via the upper transistor 71 and the S burner lower transistor 74 and the resistor 78 and the path from the GND terminal to the connection terminal 82b. . Further, the connection circuit of the present invention is constituted by the path from the Vcc terminal to the connection terminal 83a through the upper transistor 71 and G burner lower transistor 75 and the resistor 79, and the path from the GND terminal to the connection terminal 83b. .

  A connection path between the H burner lower stage transistor 72 and the resistor 76 is connected to an A / D (analog / digital) input port AD 1 of the microcomputer 60. The inter-terminal voltage detection unit 62 converts an analog voltage input to the A / D input port AD1 (voltage applied to the holding coil 15a of the H burner electromagnetic valve 15; hereinafter referred to as H burner electromagnetic valve answer Hans) into a digital value. Convert to, read and detect.

  Similarly, the connection path between the M burner lower stage transistor 73 and the resistor 77 is connected to the A / D input port AD2 of the microcomputer 60, and the connection path between the S burner lower stage transistor 74 and the resistor 78 is the A / D of the microcomputer 60. The connection path between the G burner lower stage transistor 75 and the resistor 79 is connected to the A / D input port AD 4 of the microcomputer 60.

  The inter-terminal voltage detection unit 62 includes an analog voltage input to the A / D input port AD2 (voltage applied to the holding coil 25a of the M burner electromagnetic valve 25, hereinafter referred to as M burner electromagnetic valve answer Mans), Analog voltage input to the A / D input port AD3 (voltage applied to the holding coil 35a of the S burner solenoid valve 35; hereinafter referred to as S burner solenoid valve answer Sans) and input to the A / D input port AD4 An analog voltage (a voltage applied to the holding coil 45a of the G burner electromagnetic valve 45; hereinafter referred to as a G burner electromagnetic valve answer Gans) is converted into a digital value, read, and detected.

  Next, the failure detection process of the solenoid valve drive circuit 70 executed when the M burner point fire extinguishing button 24 is ignited by the user according to the flowcharts shown in FIGS. 3 and 4 will be described. A similar failure detection process is also performed when the H burner point fire extinguishing button 14, the S burner point fire extinguishing button 34, and the G burner point fire extinguishing button 44 are ignited.

  When the M burner point fire extinguishing button 24 is ignited by the user, the M burner micro switch 27 is switched from OFF (open state) to ON (closed state) as described above. Power supply to 50 is started. Then, the microcomputer 60 is activated to start processing according to the flowcharts of FIGS.

  In STEP 1, when the operation state detection unit 61 detects that the M burner micro switch 27 is ON (closed state), the process proceeds to STEP 2. In STEP 2, the microcomputer 60 starts a switch input process for confirming the input state of the model setting switch 55 and a cooking mode setting switch (not shown) (a switch for setting a cooking mode such as boiling or fried food).

  The model setting switch 55 and the like are assigned to the key matrix scan circuit, and the operation state of each switch is input to the microcomputer 60 at predetermined intervals. In order to prevent erroneous input due to noise, the microcomputer 60 recognizes the operation state of each switch on condition that the operation state does not change over several cycles.

  Subsequent STEP 3 to STEP 8 are processes by the failure detection unit 63. In STEP 3, the failure detection unit 63 controls the conduction of the upper transistor 71 and controls the H burner lower transistor 72, the M burner lower transistor 73, the S burner lower transistor 74, and the G burner lower transistor.

  In the next STEP 4, the failure detection unit 63 detects the H burner solenoid valve answer Hans, the M burner solenoid valve answer Mans, the S burner solenoid valve answer Sans, and the G burner solenoid valve answer detected by the inter-terminal voltage detector 62. It is determined whether or not all the Gans are OFF (GND level).

  Here, if both the upper transistor 71 and the lower transistors 72 to 75 are operating normally, the upper transistor 71 is turned on and the lower transistors 72 to 75 are turned off. Therefore, the A / D ports AD1 to AD4 are disconnected from the Vcc terminal, and the H burner solenoid valve answer Hans, the M burner solenoid valve answer Mans, the S burner solenoid valve answer Sans, and the G burner solenoid valve answer Gans are all OFF. Become.

  On the other hand, when the H burner lower stage transistor 72 is in an ON failure (failure maintained in a conductive state regardless of the level of the control input), the H burner solenoid valve answer Hans is turned ON (Vcc level).

  Similarly, when the M burner lower stage transistor 73 has an ON failure, the M burner solenoid valve answer Mans is ON, and when the S burner lower stage transistor 74 has an ON fault, the S burner solenoid valve answer Sans is ON. When the G burner lower stage transistor 75 is in an ON failure, the G burner solenoid valve answer Gans is turned ON.

  Therefore, in STEP 4, when all the solenoid valve answers (Hans, Mans, Sans, Gans) are not OFF (when at least one of the lower transistors 72 to 75 is ON-failed), FIG. Branching to STEP 23, the failure detector 63 controls the upper transistor 71 to be shut off. Further, the failure detection unit 63 performs cutoff control on the H burner lower transistor 72, the M burner lower transistor 73, the S burner lower transistor 74, and the G burner lower transistor 75.

  In STEP 24, failure notification by the failure notification unit 64 is performed. The failure notification unit 64 displays an error code indicating that a failure has occurred in the electromagnetic valve drive circuit 70 on the display unit 52.

  On the other hand, when all the solenoid valve answers (Hans, Mans, Sans, Gans) are OFF in STEP4, the process proceeds to STEP5. The failure detection unit 63 controls the upper transistor 71 to shut off, and controls the conduction of the H burner lower transistor 72, the M burner lower transistor 73, the S burner lower transistor 74, and the G burner lower transistor 75.

  In the next STEP 6, the failure detection unit 63 detects the H burner solenoid valve answer Hans, the M burner solenoid valve answer Mans, the S burner solenoid valve answer Sans, and the G burner solenoid valve answer detected by the inter-terminal voltage detector 62. It is determined whether or not Gans is OFF (GND level).

  Here, if both the upper transistor 71 and the lower transistors 72 to 75 are operating normally, the upper transistor 71 is cut off and the lower transistors 72 to 75 are turned on. Therefore, the A / D ports AD1 to AD4 are disconnected from the Vcc terminal, and the H burner solenoid valve answer Hans, the M burner solenoid valve answer Mans, the S burner solenoid valve answer Sans, and the G burner solenoid valve answer Gans are all OFF. Become.

  On the other hand, when the upper transistor 71 is in an ON failure, if the lower transistors 72 to 75 are not in an OFF failure, the A / D ports AD1 to AD4 are connected to the Vcc terminal via the lower transistors 72 to 75 and the upper transistor 71. Conducted to. Therefore, the H burner solenoid valve answer Hans, the M burner solenoid valve answer Mans, the S burner solenoid valve answer Sans, and the G burner solenoid valve answer Gans are all turned ON.

  Therefore, when all the solenoid valve answers (Hans, Mans, Sans, Gans) are not OFF in STEP 6 (when the upper transistor 71 is ON failure), the process branches to STEP 23 in FIG. The unit 63 controls the upper transistor 71, the H burner lower transistor 72, the M burner lower transistor 73, the S burner lower transistor 74, and the G burner lower transistor 75. In STEP 24, failure notification by the failure notification unit 64 is performed.

  On the other hand, when all the solenoid valve answers (Hans, Mans, Sans, Gans) are OFF in STEP 6 (when the upper transistor 71 is not ON-failed), the process proceeds to STEP 7. The failure detection unit 63 controls conduction of the upper transistor 71 and the M burner lower transistor 73. Further, the failure detection unit 63 performs cutoff control on the S burner lower transistor 74, the H burner lower transistor 72, and the G burner lower transistor 75.

  Here, if both the upper transistor 71 and the M burner lower transistor 73 are operating normally, both the upper transistor 71 and the M burner lower transistor 73 become conductive. Therefore, the M burner solenoid valve answer Mans is turned ON.

  On the other hand, when at least one of the upper stage transistor 71 and the lower stage transistor 73 of the M burner has an OFF fault (a fault that is maintained in the shut-off state regardless of the level of the control input), the M burner solenoid valve answer Mans Becomes OFF level.

  Therefore, when the M burner solenoid valve answer is OFF in STEP 8 (when at least one of the upper transistor 71 or the lower transistor 73 is in an OFF failure), the process branches to STEP 23 in FIG. The upper transistor 71, the M burner lower transistor 73, the H burner lower transistor 72, the S burner lower transistor 74, and the G burner lower transistor 75 are controlled to be cut off. In STEP 24, failure notification by the failure notification unit 64 is performed.

  On the other hand, when the M burner solenoid valve answer is ON in STEP 8 (when the OFF failure of the upper transistor 71 and the M burner lower transistor 73 has not occurred), the process proceeds to STEP 9 in FIG. STEP 9 is processing by the combustion control unit 65, and the combustion control unit 65 starts the combustion operation of the M burner 20.

  The next STEP 10 to STEP 12 are processes performed by the failure detection unit 63. The failure detection unit 63 controls the conduction of the H burner lower transistor 72, the S burner lower transistor 74, and the G burner lower transistor 75 in STEP10. In this case, since it is confirmed in STEP 8 that the upper transistor 71 is ON, if the H burner lower transistor 72 is operating normally, the H burner lower transistor 72 becomes conductive. Then, the H burner solenoid valve answer Hans detected by the inter-terminal voltage detector 62 is turned on.

  Similarly, if the S burner lower stage transistor 74 is operating normally, the S burner lower stage transistor 74 becomes conductive. Then, the S burner solenoid valve answer Sans detected by the inter-terminal voltage detector 62 is turned ON.

  If the G burner lower stage transistor 75 is operating normally, the G burner lower stage transistor 75 becomes conductive. Then, the G burner solenoid valve answer Gans detected by the inter-terminal voltage detector 62 is turned on.

  Therefore, when all of the H burner solenoid valve answer Hans, the S burner solenoid valve answer Sans, and the G burner solenoid valve answer Gans are ON in STEP 11, the H burner lower stage transistor 72, the S burner lower stage transistor 74, and the G burner It can be determined that no OFF failure has occurred in any of the lower transistors 75.

  Therefore, in this case, the process proceeds to STEP 12, and the failure detection unit 63 controls to shut off the H burner lower transistor 72, the S burner lower transistor 74, and the G burner lower transistor 75, proceeds to STEP 13, and ends the process.

  On the other hand, if any of the H burner solenoid valve answer Hans, the S burner solenoid valve answer Sans, and the G burner solenoid valve answer Gans is OFF in STEP 11, the process branches to STEP 20. Then, the failure notification unit 64 waits for the input of the model setting switch 55 to be confirmed and proceeds to STEP 21.

  In STEP 21, the failure notification unit 64 recognizes the connection circuit to which the holding coil of the electromagnetic valve is connected among the connection circuits of the electromagnetic valve drive circuit 70 from the model code set by the model setting switch 55. In this embodiment, the holding coil 15a of the H burner solenoid valve 15, the holding coil 25a of the M burner solenoid valve 25, the holding coil 35a of the S burner solenoid valve 35, and the holding coil 45a of the G burner solenoid valve 45 are connected to the connection circuit. It is recognized that it is connected.

  In subsequent STEP 22, the failure notification unit 64 determines whether or not the holding coil of the solenoid valve in which the solenoid valve answer is OFF is not connected. Here, for example, in a gas stove of a model in which the S burner is not mounted, the components (S burner lower stage transistor 74, resistor 78) of the connection circuit for the solenoid valve of the S burner are not mounted. Therefore, the A / D port AD3 is not conducted to Vcc, and the S burner solenoid valve answer Sans is turned off.

  Therefore, when the solenoid valve answer that has not been turned ON corresponds to a solenoid valve for a burner that is not mounted, the solenoid valve drive circuit is not caused by a failure. The failure notification by the unit 64 is not performed.

  On the other hand, when the solenoid valve answer that has not been turned on corresponds to the solenoid valve for the burner that is mounted, an OFF fault has occurred in the lower transistor. Therefore, in this case, the process proceeds to STEP23.

  In STEP 23, the failure notification unit 64 controls the upper transistor 71, the M burner lower transistor 73, the H burner lower transistor 72, the S burner lower transistor 74, and the G burner lower transistor 75 together. In subsequent STEP 24, failure notification by the failure notification unit 64 is performed.

  Next, with reference to FIG. 5, a timing chart when processing according to the flowcharts of FIGS.

  t1 is the time when the M burner point extinguishing button 24 is ignited by the user, and in response to this ignition operation, the M burner micro switch 27 is switched from OFF (open) to ON (closed) to supply power (power 51 Power supply to the controller 50). After the power supply voltage rises at t2, the RESET input of the microcomputer 60 is switched from OFF to ON at t3, and the microcomputer 60 starts to operate (indicated by microcomputer STOP → RUN in the figure).

  The microcomputer 60 starts processing according to the flowcharts of FIGS. 3 to 4 after waiting for a predetermined stabilization time and at t4 after performing the initialization processing. At t4, the failure detection unit 63 controls the conduction of the upper transistor 71 and also controls the lower transistors 72 to 75 so as to determine whether or not each solenoid valve answer (Hans, Mans, Sans, Gans) is OFF. (Detection of ON failure of lower transistors 72 to 75).

  In addition, the failure detection unit 63 controls the upper transistor 71 to be cut off at t5, and controls the lower transistors 72 to 75 to be turned on to determine whether the solenoid valve answer (Hans, Mans, Sans, Gans) is OFF. (Detection of ON failure of upper transistor 71).

  Next, at t6, the failure detection unit 63 controls conduction of both the upper transistor 71 and the M burner lower transistor 73 to determine whether or not the M burner solenoid valve answer Mans is ON (the upper transistor 71 and Detection of the presence or absence of an OFF failure of the M burner lower transistor 73).

  Subsequently, at t7, the failure detection unit 63 controls the conduction of the H burner lower transistor 72, the S burner lower transistor 74, and the G burner lower transistor 75, and the H burner solenoid valve answer Hans, the S burner solenoid valve answer Sans, and G It is determined whether or not the burner solenoid valve answer Gans is all ON (detection of the presence or absence of an OFF failure of the H burner lower transistor 72, the S burner lower transistor 74, and the G burner lower transistor 75).

  Here, the S burner electromagnetic valve answer Sans and the G burner electromagnetic valve answer Gans are ON, but the H burner electromagnetic valve answer Hans is OFF (OFF failure of the H burner lower stage transistor 72). Therefore, failure notification is performed by the failure notification unit 64.

  Here, since the switch input process is started in STEP2 of FIG. 3, the input of the model setting switch 55 is confirmed at t8. Therefore, without waiting for the input of the model setting switch 55 to be confirmed, the OFF failure of the H burner lower transistor 72, the S burner lower transistor 74, and the G burner transistor 75 can be quickly detected and a failure notification can be made.

  In this embodiment, in STEP 20 to STEP 22 of FIG. 4, the gas stove model is discriminated and the connection state of the solenoid valve according to the model is recognized, and the connection is limited to the connection circuit to which the solenoid valve is connected. Although the failure has been notified, this recognition is not necessary when the solenoid valve drive circuit 70 is a dedicated circuit in which the number of solenoid valves to be connected does not change.

  In this embodiment, the timing for recognizing the connection state of the model-specific solenoid valves of STEP 20 to STEP 22 of FIG. 4 is advanced by starting input processing of the model setting switch 55 in STEP 2 of FIG. The effect of the present invention can also be obtained when the input processing of the model setting switch 55 is started immediately before STEP 20.

  Further, in the present embodiment, the configuration in which the upper transistor 71 is commonly provided for the holding coil of each electromagnetic valve is shown, but the upper transistor may be individually provided for the holding coil of each electromagnetic valve.

  In the present embodiment, the connection circuit of the solenoid valve drive circuit 70 is configured to connect the holding coil of each solenoid valve between the output terminals of the power supply via the two switching elements. The present invention can also be applied to a configuration in which a connection is made between output terminals of a power supply via a switching element.

  In this embodiment, an example in which a transistor is used as the switching element of the present invention has been described. However, other types of switching elements such as FETs and relays may be used.

  DESCRIPTION OF SYMBOLS 1 ... Gas stove, 10 ... H burner, 14 ... H burner point fire extinguishing button, 15 ... H burner solenoid valve, 17 ... H burner micro switch, 20 ... M burner, 24 ... M burner point fire extinguishing button, 25 ... M burner Solenoid valve, 27 ... M burner micro switch, 30 ... S burner, 34 ... S burner point fire extinguishing button, 35 ... S burner solenoid valve, 37 ... S burner micro switch, 40 ... G burner, 44 ... G burner point fire extinguishing button, 45 ... G burner solenoid valve, 47 ... G burner micro switch, 50 ... controller, 51 ... power supply, 55 ... model setting switch, 60 ... microcomputer, 61 ... operation state detector, 62 ... inter-terminal voltage detector, 63 ... Failure detection unit, 64 ... Failure detection unit, 65 ... Combustion control unit, 70 ... Solenoid valve drive circuit, 71 ... Upper transistor, 72 ... H burner lower transistor, 73 ... M bar The lower transistor, 74 ... S burner lower transistor, 75 ... G burner lower transistor.

Claims (3)

Two or more predetermined number of burners;
Power supply,
An ignition operation unit that is individually provided for each burner and that performs an ignition operation of a corresponding burner;
Provided individually for each burner, opens and closes the fuel gas supply path of the corresponding burner, and switches from the valve-closed state to the valve-opened state according to the ignition operation of the ignition operation unit for the corresponding burner A solenoid valve that is maintained in an open state by energizing the holding coil in the open state,
A connection circuit for connecting a pair of output terminals of the power supply to a pair of connection terminals via a plurality of switching elements has the predetermined number or more, and the holding coils of the solenoid valves are connected to the connection terminals of the predetermined number or more. A solenoid valve drive circuit that is assigned and connected one by one,
An operation state detection unit for detecting an operation state of each ignition operation unit;
An inter-terminal voltage detector for detecting a voltage between the connection terminals;
When the operation state detection unit detects that any one of the ignition operation units is ignited, the plurality of switching of the connection circuit for the burner corresponding to the ignition operation unit subjected to the ignition operation By controlling all the elements to conduct and determining whether or not the voltage between the connection terminals of the connection circuit detected by the inter-terminal voltage detection unit is equal to or higher than a predetermined voltage, A failure detection unit that detects presence or absence;
In the gas stove provided with a failure notification unit that performs failure notification when a failure of the connection circuit is detected by the failure detection unit,
The failure detection unit is other than the burner corresponding to the ignition operation unit on which the ignition operation is performed when the operation state detection unit detects that any ignition operation of the ignition operation unit has been performed. Also for the connection circuit for the burner, all of the plurality of switching elements are subjected to conduction control, and the voltage between the connection terminals of the connection circuit detected by the inter-terminal voltage detection unit is the predetermined voltage. A gas stove characterized by detecting a failure of the connection circuit by determining whether or not the above is true. The gas stove according to claim 1, wherein
A coil connection information holding unit holding coil connection information indicating the presence or absence of connection of a holding coil of the electromagnetic valve to each connection circuit of the electromagnetic valve drive circuit;
The failure notification unit recognizes the connection circuit to which the holding coil of the solenoid valve is connected based on the coil connection information, and only notifies the failure notification of the connection circuit to which the holding coil of the solenoid valve is connected. A gas stove characterized in that the connection circuit to which the holding coil of the solenoid valve is not connected is excluded from the failure notification target. The gas stove according to claim 2, wherein
The failure notification unit reads the coil connection information from the coil connection information holding unit in parallel with the detection of the presence / absence of failure of all the connection circuits by the failure detection unit, and the failure detection unit The connection to which the holding coil of the electromagnetic valve is connected at the time when the detection of the presence / absence of a failure in all of the connection circuits and the reading of the coil connection information from the coil connection information holding unit are completed. A gas stove that determines whether or not a failure has been detected by the failure detection unit for the circuit, and performs the failure notification according to the determination.

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