JP7560349B2 - Gas cooker - Google Patents

Description

The present invention relates to gas cooking appliances such as gas stoves and gas grills.

Some gas cookers respond to the user's ignition operation by supplying fuel gas to a gas burner and starting an ignition operation to generate an ignition spark, and if it is determined that the gas burner has ignited within a specified time from the ignition operation, the generation of sparks is stopped and the ignition operation is terminated, and combustion continues thereafter.

In such a gas cooker, if it is not determined that ignition has occurred within the specified time period after the ignition operation, it is determined that there is an ignition error, and the supply of fuel gas to the gas burner is stopped and the generation of ignition sparks is stopped.

The time required from when the user performs the ignition operation until it is determined that the gas burner has ignited may be longer depending on, for example, differences in the fuel gas supply pressure depending on where the gas cooker is installed.

When the time required from the user's ignition operation to the determination that the gas burner has ignited becomes longer in this way, in conventional examples in which the predetermined time is fixed, it is not possible to determine that the gas burner has ignited within the predetermined time, and the number of ignition errors increases. When ignition errors occur frequently, the user will have to make a maintenance call. An increase in the number of maintenance calls is undesirable for both the user and the manufacturer.

For this reason, Patent Document 1 proposes a control device for a gas burning appliance that continues the ignition operation while the user continues the ignition operation, regardless of the passage of a predetermined time, and makes it possible to ignite the gas burner even if the time required from the user's ignition operation to the determination that the gas burner has ignited becomes long.

JP 2001-50536 A

In the above-mentioned Patent Document 1, while the user continues the ignition operation, the ignition operation continues by supplying fuel gas to the gas burner to generate an ignition spark. Therefore, if the ignition operation continues for too long, the amount of fuel gas supplied becomes too large, increasing the risk of explosive ignition (explosive combustion).

The present invention was made in consideration of the above-mentioned points, and aims to prevent explosive ignition while suppressing the occurrence of ignition errors.

In order to achieve the above objective, the present invention is configured as follows:

(1) A gas cooker according to the present invention is a gas cooker comprising a gas burner to which fuel gas is supplied, an ignition plug for igniting the gas burner, an igniter to which the ignition plug is electrically connected, an operation unit that is operated to ignite the gas burner, a flame detection sensor that detects a flame of the gas burner, and control means for controlling the supply of fuel gas to the gas burner and the igniter based on the ignition operation of the operation unit and the detection output of the flame detection sensor,
The control means includes a judgment unit which judges whether or not the gas burner has been ignited based on the detection output of the flame detection sensor, and in response to an ignition operation of the operating unit, the control means starts the supply of fuel gas to the gas burner and starts driving the igniter to generate a spark discharge in the ignition plug, and if the judgment unit judges that the gas burner has been ignited before a predetermined time has elapsed since the ignition operation, stops the driving of the igniter, and if the predetermined time has elapsed without the judgment unit judging that the gas burner has been ignited, stops the supply of fuel gas to the gas burner and stops the driving of the igniter, and the control means varies the predetermined time within a predetermined upper limit time.

According to the present invention, the control means responds to the user's ignition operation by starting the supply of fuel gas to the gas burner and starting the drive of the igniter to generate a spark discharge in the ignition plug, and if it is determined that the gas burner has ignited before a predetermined time has elapsed since the ignition operation, it can stop the drive of the igniter and continue combustion. Also, if the predetermined time has elapsed without it being determined that the gas burner has ignited, it can stop the supply of fuel gas to the gas burner and stop the drive of the igniter to stop the ignition operation as an ignition error so as to prevent explosive ignition.

Furthermore, the control means varies the specified time within a predefined upper limit time.

In this way, the control means can vary the specified time, so that the specified time can be set according to the time required from the user's ignition operation to the determination that the gas burner has ignited. For example, when the time required from the user's ignition operation to the determination that the gas burner has ignited is long due to differences in fuel gas supply pressure depending on the location where the gas cooker is installed, the occurrence of ignition errors can be suppressed by lengthening the specified time.

In addition, the specified time is variable within a predefined upper limit, so by setting this upper limit to a long time that will not cause explosive ignition of the gas burner, explosive ignition can be avoided, ensuring safety.

In this way, the gas cooker of the present invention is safe by avoiding explosive ignition, and is easy to use as it reduces the occurrence of ignition errors.

Furthermore, the gas cooker of the present invention is provided with a plurality of gas burners having different ignition powers, and the control means varies the specified time according to the ignition power of the gas burners, so that the smaller the ignition power of the gas burners, the longer the specified time is.

The smaller the ignition power of a gas burner, the less likely it is that explosive ignition will occur, even if the specified time is longer. In other words, the time from the ignition operation until explosive ignition occurs varies depending on the ignition power of the gas burner. In contrast, in conventional examples in which the specified time is fixed to a constant time, the specified time is not appropriate for the ignition power. For this reason, for example, if a gas burner with a large ignition power is fixed to a short specified time at which explosive ignition does not occur, a gas burner with a small ignition power may not be able to determine that the gas burner has ignited before the short specified time has elapsed, which may result in an ignition error.

According to this embodiment, the specified time is variable within the upper limit time according to the ignition power of the gas burner, and the smaller the ignition power of the gas burner, the longer the specified time is. This provides an appropriate specified time according to the ignition power of the gas burner, and prevents explosive ignition while maintaining safety and suppresses the occurrence of ignition errors, improving usability.

(2) In one embodiment of the present invention, the control means includes a timing unit which measures the combustion stop time of the gas burner, and the control means varies the specified time in accordance with the combustion stop time, such that the longer the combustion stop time, the longer the specified time is.

If the gas burner combustion stop time is long, the fuel gas in the gas pipeline is diluted or replaced by air, so the time required from the user's ignition operation to the determination that the gas burner has ignited increases. For this reason, in conventional examples in which the specified time is fixed at a constant time, if the gas burner combustion stop time is long, it is not possible to determine whether the gas burner has ignited before the specified time has elapsed, increasing the risk of an ignition error.

In this embodiment, the specified time is variable within the upper limit time according to the time the gas burner stops burning, and the longer the burning stop time, the longer the specified time is. This prevents explosive ignition and maintains safety, while suppressing the occurrence of ignition errors, improving usability.

(3) In another embodiment of the present invention, a temperature detection unit is provided which detects the temperature of the gas burner, and the control means varies the specified time in accordance with the temperature detected by the temperature detection unit, such that the lower the detected temperature, the longer the specified time is set.

In this embodiment, the specified time can be varied within the upper limit time according to the user's setting operation. Therefore, if there are reasons specific to the location where the gas cooker is installed, such as the fuel gas components being supplied being uneven and making ignition difficult, or the gas cooker being installed in an area or building with low fuel gas supply pressure, the user can set an appropriate specified time according to the installation location. This makes it possible to prevent explosive ignition and maintain safety, while suppressing the occurrence of ignition errors, improving convenience.

(4) In a preferred embodiment of the present invention, an installation status detection unit is provided which detects that the gas cooker has been installed in a new installation location, and the control means varies the specified time based on the detection output of the installation status detection unit, and makes the specified time longer until the judgment unit first judges that the gas burner has been ignited by an ignition operation when the gas cooker is installed in a new installation location than the specified time thereafter.

According to this embodiment, when the installation state detection unit detects that the gas cooker has been installed in a new installation location, the predetermined time is lengthened until the determination unit first determines that the gas burner has been ignited by the ignition operation. For example, when the gas cooker is installed in a newly built apartment building, where the apartment building's gas piping is long and ignition operations and ignition errors are repeated many times before the fuel gas reaches the gas cooker, the number of ignition operations and ignition errors can be reduced by lengthening the predetermined time. This reduces the workload of the worker when installing the gas cooker in a new installation location.

(5) In another embodiment of the present invention, the power source of the control means is a replaceable battery loaded into the battery loading section or a commercial power source (100 V power source), and the installation status detection section detects that the battery has been installed in a new installation location when it is first loaded into the battery loading section or when it is first connected to the commercial power source (100 V power source).

According to this embodiment, the gas cooker detects that it has been installed in a new installation location when the battery is loaded into the battery loading section for the first time after shipment, or when it is first connected to the commercial power source (100V power source), making it possible to reliably detect that the gas cooker has been installed in a new installation location.

(6) In yet another embodiment of the present invention, a plurality of the gas burners are arranged on the top plate of the gas cooker, and the control means varies the specified time depending on the position of the gas burner on the top plate, so that the further the position of the gas burner is from the user, the longer the specified time is.

In this embodiment, among the multiple gas burners, the one located on the top plate farther from the user has a longer predetermined time than the one located closer to the user. Therefore, even if an explosive ignition occurs within the extended predetermined time, the gas burner is located farther from the user, so the impact on the user is minimal and safety can be ensured.

According to the present invention, the specified time can be varied within a predetermined upper limit, so that the specified time can be set according to the time required from the user's ignition operation to the determination that the gas burner has ignited. For example, when the time required from the user's ignition operation to the determination that the gas burner has ignited is long due to differences in the fuel gas supply pressure depending on the location where the gas cooker is installed, the occurrence of ignition errors can be suppressed by lengthening the specified time.

In addition, the specified time is variable within a predefined upper limit, so by setting this upper limit to a long time that will not cause explosive ignition of the gas burner, explosive ignition can be avoided, ensuring safety.

In this way, it is possible to provide a safe, easy-to-use gas cooker that avoids explosive ignition and reduces the occurrence of ignition errors.

FIG. 1 is a perspective view of a gas stove with a grill according to an embodiment of the present invention. FIG. 2 is a schematic diagram of the grill-equipped gas stove of FIG. FIG. 3 is a time chart of a conventional example in which the predetermined time is fixed to a constant time. FIG. 4 is a time chart of this embodiment in which the predetermined time is variable. FIG. 5 is a flow chart showing a process for varying a predetermined time according to an embodiment of the present invention. FIG. 6 is a flow chart showing a process for varying a predetermined time period according to another embodiment of the present invention. FIG. 7 is a diagram showing a part of the grill cooking setting input section and the gas stove cooking setting input section.

The following describes an embodiment of the present invention with reference to the drawings.

In this embodiment, the gas cooker is a gas stove with a grill.

Figure 1 is a perspective view of a gas stove with a grill A according to one embodiment of the present invention. This gas stove with a grill A is equipped with three gas burners 2a to 2c with different maximum flame powers at the top of the stove body 1. Furthermore, the gas stove with a grill A is equipped with a grill burner (not shown) built in as a gas burner at the center of the left and right sides of the stove body 1, and is equipped with a grill section 3 on which a grill plate (not shown) with a grill door 3a at the front is attached so that it can be inserted and removed from the front.

The gas stove A with grill in this embodiment is a built-in type that is dropped into a kitchen cabinet (not shown).

The top of the stove body 1 is covered with a top plate 4, and a grill exhaust port 5 is provided on the top surface at the rear end of the stove to exhaust combustion exhaust gas from the grill section 3.

In this embodiment, one of the burners 2a, 2b arranged on the left and right sides of the front side of the top plate 4 (the left side) is the standard heat burner 2a, and the other (the right side) is the high heat burner 2b. The burner 2c arranged in the center of the back side is the low heat burner 2c. Each burner 2a-2c is equipped with a temperature sensor 7a-7c consisting of a thermistor or the like that detects the temperature of the cooking container as the heated object, for example, the bottom of a pot, and a corresponding trivet 6a-6c is placed on it.

The upper left and right sides of the front of the stove body 1 are provided with three operating parts, namely heating condition adjustment parts 8a to 8c, for controlling the ignition, extinguishing and flame adjustment of each of the stove burners 2a to 2c. In this embodiment, the heating condition adjustment part 8a for the standard flame burner 2a is located on the left side of the front, and the heating condition adjustment part 8b for the high flame burner 2b and the heating condition adjustment part 8c for the low flame burner 2c are located on the right side of the front.

In addition, an automatic reset push button type power switch 9 is provided on the upper right side of the front panel to turn the power to each section on and off.

Each of the heating condition adjustment units 8a to 8c is made up of a push button that can be moved back and forth. When using the stove burners 2a to 2c, the heating condition adjustment units 8a to 8c, which are push buttons, are pressed to perform the ignition operation, causing the retracted heating condition adjustment units 8a to 8c to protrude forward, turning on the appliance valve, and creating a spark discharge in the flowing gas fuel, igniting the stove burners 2a to 2c.

When the heating condition adjustment parts 8a-8c, which are push buttons, are pinched and rotated with the fingers while they are protruding forward, the flame power of the stove burners 2a-2c can be adjusted. On the other hand, when turning off the fire, the forward protruding heating condition adjustment parts 8a-8c are pushed backward, causing the protruding heating condition adjustment parts 8a-8c to retract backward, turning off the appliance valve and turning off the stove burners 2a-2c.

Operation panels 10, 11 are provided at the left and right lower parts of the front of the stove body 1 and can be freely stored. The right operation panel 11 is provided with a grill cooking setting input section 12 for performing operations related to the grill section 3, and this operation panel 11 serves as the grill-side operation panel. The left operation panel 10 is provided with a gas stove cooking setting input section 13 for inputting cooking settings for the stove burners 2a to 2c, and this operation panel 10 serves as the stove-side operation panel.

The grill cooking setting input unit 12 and gas stove cooking setting input unit 13 allow you to set automatic cooking using the grill unit and stove burners 2a to 2c. This automatic cooking can be done by switching the heat of the stove burners 2a to 2c to control the temperature within a certain range.

Figure 2 is a schematic diagram of the grill-equipped gas stove A in Figure 1, and parts corresponding to those in Figure 1 are given the same reference numerals.

Each of the stove burners 2a to 2c is provided with an ignition plug 14a to 14c for igniting the stove burner 2a to 2c, an igniter 22a to 22c to which the ignition plugs 14a to 14c are electrically connected, and a thermocouple 15a to 15c as a flame detection sensor for detecting the flame of each of the stove burners 2a to 2c. Each of the stove burners 2a to 2c is also provided with a temperature sensor 7a to 7c for detecting the temperature of the cooking vessel 19, for example the bottom of a pot, as described above.

Similarly, the grill section 3 is provided with spark plugs 17a, 17b for igniting the upper and lower grill burners 16a, 16b, respectively, igniters 22d, 22e to which the spark plugs 17a, 17b are electrically connected, respectively, and thermocouples 18a, 18b as flame detection sensors for detecting the flames of the grill burners 16a, 16b, respectively. Also provided is a temperature sensor 21, such as a thermistor, for detecting the temperature of the bottom of the grill pan 20.

By energizing (driving) each igniter 22a-22e, which corresponds individually to each burner 2a-2c, 16a, 16b, a spark discharge occurs in the ignition plugs 14a-14c, 17a, 17b, which correspond individually to each burner 2a-2c, 16a, 16b.

The stove burners 2a to 2c and the grill burners 16a and 16b are connected to branch supply lines 24 to 27, which are respectively branched off from a fuel supply line 23 that supplies fuel gas such as city gas.

The fuel supply passage 23 is provided with a main solenoid valve 28. Each of the branch supply passages 24-27 is provided with flow control valves 29-32, which are motor valves that are driven by stepping motors to finely adjust the opening of the valve body in order to adjust the amount of fuel gas supplied, and rotation angle sensors 33-36 that detect the opening of the valve body.

Each flow control valve 29-32 functions as a safety valve that cuts off the fuel gas supply path when each burner 2a-2c, 16a, 16b goes out.

The branch supply path 27 for the grill burners 16a and 16b is provided with a governor 37 that adjusts the fuel gas supply pressure to a set pressure.

The control unit 40, which is made up of a microcomputer, is provided with the detection outputs of the thermocouples 15a-15c, 18a, 18b and the temperature sensors 7a-7c, 21, which act as flame detection sensors that detect the flames of the burners 2a-2c, 16a, 16b, respectively, as well as the outputs of the rotation angle sensors 33-36 of the flow control valves 29-32.

The control unit 40 also receives operation input from a manual operation unit 42, which is made up of the heating condition adjustment units 8a-8c, the grill cooking setting input unit 12, and the gas stove cooking setting input unit 13. This operation input includes commands to turn on and off the burners 2a-2c, 16a, and 16b in response to the user's operation to turn on and off the burners.

The control unit 40 functions as a control means for controlling the turning on and off of each burner 2a-2c, 16a, 16b, the supply of fuel gas, and combustion based on the operation input from the manual operation unit 42, and the outputs of the thermocouples 15a-15c, 18a, 18b, each temperature sensor 7a-7c, 21, and each rotation angle sensor 33-36.

The control unit 40 also functions as a judgment unit that judges whether or not each burner 2a-2c, 16a, 16b has been ignited based on the electromotive forces of the thermocouples 15a-15c, 18a, 18b that serve as the flame detection sensors. In this judgment, when the thermocouples 15a-15c, 18a, 18b detect a flame and the electromotive force thereof becomes equal to or greater than the threshold voltage Vs, it is judged that ignition has occurred.

The control unit 40 also functions as a timer that measures the time from when combustion in each burner 2a-2c, 16a, and 16b is stopped until the next ignition operation.

The control unit 40 also functions as an installation state detection unit that detects when the gas stove A with a grill has been installed in a new installation location. The installation state detection unit in this embodiment detects that the gas stove A with a grill has been installed in a new installation location when the replaceable battery is first set (loaded) in the battery box serving as the battery loading unit after shipment.

When the user issues an ignition command by operating the ignition switch, the control unit 40 starts supplying fuel gas to the commanded burners 2a-2c, 16a, 16b, and controls the igniters 22a-22e, the main solenoid valve 28, and the corresponding flow control valves 29-32 so that the ignition operation continues for a predetermined time until it is determined that ignition has occurred based on the output (electromotive force) of the corresponding thermocouples 15a-15c, 18a, 18b. The control unit 40 is also configured to stop supplying fuel gas to the commanded burners 2a-2c, 16a, 16b when the user issues an extinguishing command by operating the extinguishing switch.

In this embodiment, the following is done to prevent explosive ignition of burners 2a-2c, 16a, and 16b while suppressing the occurrence of ignition errors.

In other words, in response to the user's ignition operation, the control unit 40 starts the supply of fuel gas to the burners 2a-2c, 16a, and 16b, and starts driving the igniters 22a-22e corresponding to the ignition operation, causing a spark discharge in the ignition plugs 14a-14c, 17a, and 17b. If it is determined that the stove burner 2a-2c corresponding to the ignition operation has ignited within a predetermined time from the ignition operation, the control unit 40 stops driving the igniters 22a-22e corresponding to the ignition operation, stops the ignition operation, and continues the combustion state.

In addition, if the predetermined time has elapsed without determining that the burners 2a-2c, 16a, and 16b corresponding to the ignition operation have ignited, the supply of fuel gas to the burners 2a-2c, 16a, and 16b corresponding to the ignition operation is stopped to prevent explosive ignition, and the drive of the igniters 22a-22e corresponding to the ignition operation is stopped to stop the ignition operation. At the same time, an ignition error is notified by flashing the combustion lamps around the heating state adjustment units 8a-8c.

Furthermore, in this embodiment, the control unit 40 varies the specified time within a predefined upper limit time.

Here, we will explain the effect of this embodiment, in which the specified time is variable within a predetermined upper limit, by comparing it with a conventional example in which the specified time is fixed at a fixed time.

The following describes stove burners 2a to 2c, but the same applies to grill burners 16a and 16b.

Figure 3 shows an example of a conventional time chart in which the predetermined time is fixed at a fixed time. (a) shows the ignition operation (ignition command) by the user, (b) shows the open/close state of the main solenoid valve 28, (c) shows the open/close state of the flow control valves 29-31, (d) shows the drive (energization) state of the igniters 22a-22c, (e) shows the flame state of the stove burners 2a-2c, (f) shows the output (electromotive force) of the thermocouples 15a-15c as flame detection sensors, (g) shows the ignition judgment result, and (h) shows the state of the combustion lamp.

In addition, in Figures 3(a) to (h), the solid lines indicate cases where ignition is performed normally within the specified time, and the dashed lines indicate cases where ignition is not performed normally within the specified time and an ignition error occurs.

First, we will explain the case shown by the solid line where ignition is normally performed within a predetermined time (ts-t0). The predetermined time (ts-t0) is, for example, 5 seconds.

At time t0, as shown in FIG. 1(a), when the user performs the ignition operation, as shown in FIG. 1(b), the main solenoid valve 28 is opened, and the flow control valves 29-31 corresponding to the ignition operation are opened, as shown in FIG. 1(c), and the supply of fuel gas to the stove burners 2a-2c corresponding to the ignition operation begins.

Also, as shown in FIG. 1(d), the igniters 22a-22c corresponding to the ignition operation are driven (ON), and a spark discharge occurs in the ignition plugs 14a-14c corresponding to the ignition operation. As a result, as shown in FIG. 1(e), for example, at time t1, a flame occurs in the stove burners 2a-2c corresponding to the ignition operation, and as shown in FIG. 1(f), the flame is detected by the thermocouples 15a-15c corresponding to the ignition operation, generating an electromotive force.

When the electromotive force of the thermocouples 15a to 15c corresponding to the ignition operation reaches the threshold voltage Vs for determining whether or not ignition has occurred within a predetermined time (ts-t0), for example at time t2, it is determined that ignition has occurred, and the ignition determination result becomes high level, as shown in FIG. 1(g). This causes the drive of the igniters 22a to 22c to stop, as shown in FIG. 1(d), and the combustion lamp turns on, as shown in FIG. 1(h), to inform the user that combustion has started, and the combustion state continues.

Next, we will explain the case shown by the dashed line in which, for example, the fuel gas supply pressure in the location where the gas cooker is installed is low, which causes a long time to pass from the time the user operates the ignition until it is determined that the gas burner has ignited, resulting in no normal ignition within the specified time (ts-t0), resulting in an ignition error.

At time t0, as shown in FIG. 1(a), when the user performs the ignition operation, as shown in FIG. 1(b), the main solenoid valve 28 is opened, and the flow control valves 29-31 corresponding to the ignition operation are opened, as shown in FIG. 1(c), and the supply of fuel gas to the stove burners 2a-2c corresponding to the ignition operation begins.

Also, as shown in FIG. 3(d), the igniters 22a to 22c corresponding to the ignition operation are driven (ON), and a spark discharge occurs in the corresponding ignition plugs 14a to 14c.

Despite the spark discharge of the ignition plugs 14a to 14c, a flame does not occur easily. For example, at time t3, a flame occurs as shown by the dashed line in the same figure (e). As shown by the dashed line in the same figure (f), the flame is detected by the thermocouples 15a to 15c corresponding to the ignition operation, and an electromotive force is generated.

The flame is generated slowly, and the electromotive force of the thermocouples 15a to 15c corresponding to the ignition operation cannot reach the threshold voltage Vs for determining whether or not ignition has occurred by the time ts when a predetermined time (ts-t0) has elapsed, as shown by the dashed line in FIG. 1(f). Therefore, at time ts, as shown by the dashed lines in FIG. 1(b) and FIG. 1(c), the main solenoid valve 28 and the corresponding flow control valves 29 to 32 are closed to stop the supply of fuel gas, as shown by the dashed lines in FIG. 1(d), the drive of the igniters 22a to 22c corresponding to the ignition operation is stopped to end the ignition operation, as shown by the dashed line in FIG. 1(h), and the combustion lamp is blinked to notify the user of an ignition error. With the ignition operation being stopped at time ts, the flame goes out, as shown by the dashed line in FIG. 1(e), and the electromotive force of the thermocouples 15a to 15c corresponding to the ignition operation decreases, as shown by the dashed line in FIG. 1(f).

In the example of Figure 3, a flame occurs at time t3 within the specified time (ts-t0). However, if no flame occurs within the specified time (ts-t0), the electromotive force of the thermocouple shown in Figure 3(f) is not generated and does not reach the threshold voltage Vs for determining whether or not ignition has occurred, resulting in an ignition error.

Next, an example of a time chart of this embodiment in which the specified time is variable within a predetermined upper limit time will be described with reference to FIG. 4. This FIG. 4 corresponds to FIG. 3, and like FIG. 3, FIG. 4(a) shows the ignition operation (ignition command) by the user, FIG. 4(b) shows the open/close state of the main solenoid valve 28, FIG. 4(c) shows the open/close state of the flow control valves 29-31, FIG. 4(d) shows the drive (energization) state of the igniters 22a-22c, FIG. 4(e) shows the flame state of the stove burners 2a-2c, FIG. 4(f) shows the output (electromotive force) of the thermocouples 15a-15c as flame detection sensors, FIG. 4(g) shows the ignition judgment result, and FIG. 4(h) shows the state of the combustion lamp.

In Figure 4, the solid and dashed lines correspond to the solid and dashed lines in Figure 3 above.

In FIG. 4, the specified time is set to a longer time within a predetermined upper limit. Specifically, the specified time (ts'-t0) is longer than the specified time (ts-t0) in FIG. 3 above, taking a longer time from time ts to time ts'. This specified time (ts'-t0) is, for example, 10 seconds.

First, as shown by the solid line in FIG. 4, at time t0, when the user performs an ignition operation (ignition command) as shown in FIG. 4(a), the main solenoid valve 28 is opened as shown in FIG. 4(b), and the flow control valves 29-31 corresponding to the ignition operation are opened as shown in FIG. 4(c), and the supply of fuel gas to the stove burners 2a-2c corresponding to the ignition operation begins.

Also, as shown in FIG. 1(d), the igniters 22a-22c corresponding to the ignition operation are driven (ON), and a spark discharge occurs in the ignition plugs 14a-14c corresponding to the ignition operation. As a result, as shown in FIG. 1(e), for example, at time t1, a flame occurs in the stove burners 2a-2c corresponding to the ignition operation, and as shown in FIG. 1(f), the flame is detected by the thermocouples 15a-15c corresponding to the ignition operation, generating an electromotive force.

When the electromotive force of the thermocouples 15a to 15c corresponding to the ignition operation reaches the threshold voltage Vs for determining whether or not ignition has occurred within a predetermined time (ts'-t0), for example at time t2, it is determined that ignition has occurred, as shown in FIG. 1(g), and the ignition determination result becomes high level. As shown in FIG. 1(d), the drive of the igniters 22a to 22c is stopped, and as shown in FIG. 1(h), the combustion lamp is turned on, notifying the user that combustion has started, and the combustion state continues.

The above is the same as when ignition is performed normally, as shown by the solid line in Figure 3 above.

Next, we will explain a case where, for example, the fuel gas supply pressure in the location where the gas cooker is installed is low, which causes a long time from the user's ignition operation until it is determined that the gas burner has ignited, resulting in an ignition error, as shown by the dashed line in Figure 3 above.

At time t0 in FIG. 4, when the user performs the ignition operation as shown in FIG. 4(a), the main solenoid valve 28 is opened as shown in FIG. 4(b), and the flow control valves 29-31 corresponding to the ignition operation are opened as shown in FIG. 4(c), and the supply of fuel gas to the stove burners 2a-2c corresponding to the ignition operation begins.

Also, as shown in FIG. 1(d), the igniters 22a to 22c corresponding to the ignition operation are driven (ON), and a spark discharge occurs in the ignition plugs 14a to 14c corresponding to the ignition operation.

Despite the spark discharge of the ignition plugs 14a to 14c, a flame does not occur easily. For example, at time t3, a flame occurs as shown by the dashed line in the same figure (e). As shown by the dashed line in the same figure (f), the flame is detected by the thermocouples 15a to 15c corresponding to the ignition operation, and an electromotive force is generated.

The flame is generated slowly, and it takes a long time for the electromotive force of the corresponding thermocouples 15a to 15c to reach the threshold voltage Vs for determining whether or not ignition has occurred, as shown by the dashed line in FIG. 1(f), but the predetermined time (ts'-t0) is extended as described above. As a result, the electromotive force of the thermocouples 15a to 15c corresponding to the ignition operation reaches the threshold voltage Vs for determining whether or not ignition has occurred at time t4 within the predetermined time (ts'-t0), and it is determined that ignition has occurred, as shown by the dashed line in FIG. 1(g), and the ignition determination result becomes high level. As a result, the drive of the igniters 22a to 22c is stopped, as shown by the dashed line in FIG. 1(d), and the combustion lamp is turned on, as shown by the dashed line in FIG. 1(h), to notify the user that combustion has started and to continue the combustion state.

In the conventional example of FIG. 3, where the predetermined time is fixed at a certain time, even if an ignition error occurs, if the predetermined time is made variable within a predetermined upper limit time and extended as in FIG. 4, normal ignition will occur without an ignition error.

The predetermined upper limit time is the time during which explosive ignition of the stove burners 2a to 2c does not occur, and is preferably as long as possible, for example, 16 seconds.

In this way, the specified time can be varied within a predetermined upper limit time in which explosive ignition of the stove burners 2a to 2c does not occur, making it possible to avoid explosive ignition, and the specified time can be set according to the time required from the user's ignition operation to the determination that the gas burner has ignited, making it possible to suppress the occurrence of ignition errors and improving usability.

Next, a more specific embodiment will be described with reference to a flowchart.

Figure 5 is a flowchart showing the variable processing of a predetermined time in one embodiment of the present invention.

In FIG. 5, the specified time is varied within a predetermined upper limit time, for example, within 16 seconds, depending on whether the gas stove with grill A has been installed in a new location, the combustion stop time of the stove burners 2a to 2c, and the temperature of the stove burners 2a to 2c.

First, when the user performs an ignition operation, i.e., issues an ignition command (step S1), it is determined whether there is a history of ignition at the new installation location (step S2).

When gas stove A with a grill is installed in a new location, for example in a newly built apartment building, the fuel gas piping is long, so it takes time for the fuel gas to reach gas stove A with a grill. As a result, even if an ignition operation is performed, it will not ignite within the specified time, resulting in an ignition error, and the ignition operation and ignition error will be repeated.

In this embodiment, in step S2, when the control unit 40, which serves as the above-mentioned installation state detection unit, detects that the gas stove A with a grill has been installed in a new installation location, it determines whether there is an ignition history at this new installation location, that is, whether there is a history of an initial ignition determination that determined that the gas stove A with a grill has ignited at the new installation location. If there is no ignition history at the new installation location, since the gas stove A with a grill has not yet ignited since being installed in the new installation location, the process moves to step S3, where the predetermined time is set to a long time within the upper limit time, for example 10 seconds, and the ignition operation is started (step S4).

In this way, the predetermined time is extended until the first ignition is confirmed after the grill-equipped gas stove A is installed in a new installation location, so the number of repeated ignition operations and ignition errors can be reduced compared to when the predetermined time is short. This reduces the workload of the worker when installing the grill-equipped gas stove A in a new installation location.

If it is determined in step S2 above that there is a history of ignition at the new installation location, it is assumed that gas stove A with grill has been installed in the new installation location and has already been ignited and lit, and the process moves to step S5.

If the burner combustion stop time is long, the fuel gas in the gas pipeline is diluted or replaced by air, so the time required from the user's ignition operation to the burner ignition determination becomes long. Therefore, in step S5, it is determined whether the combustion stop time of the burner 2a to 2c that has been ignited is equal to or longer than the threshold time tm. This threshold time tm can be set within a relatively wide time range, and may be, for example, about 5 hours.

In step S5, if the combustion stop time of the stove burners 2a to 2c corresponding to the ignition operation is equal to or longer than the threshold time tm, a long time has passed since combustion was stopped, and it is assumed that the time required from the user's ignition operation to the ignition determination of the stove burners 2a to 2c will be long, so the process moves to step S3, where the predetermined time is lengthened within the upper limit time, for example to 10 seconds, and the ignition operation is started (step S4).

In step S5 above, if the combustion stop time of the ignition-operated stove burner is not equal to or longer than the threshold time tm, i.e., if a long time has not elapsed since combustion was stopped, the process proceeds to step S6.

The lower the temperature of the stove burners 2a to 2c, the lower the temperature of the fuel gas, and the narrower the explosion limit of the gas at low temperatures, which may make ignition difficult. Therefore, in step S6, it is determined whether the temperature detected by the temperature sensors 7a to 7c corresponding to the ignited stove burners 2a to 2c is equal to or lower than the threshold temperature TL. This threshold temperature TL may be, for example, about 20°C.

In step S6, if the temperature detected by the temperature sensor 7a-7c corresponding to the ignited stove burner 2a-2c is equal to or lower than the threshold temperature TL, it is determined that the temperature of the ignited stove burner 2a-2c is low and the time required from the user's ignition operation to the ignition determination of the stove burner 2a-2c is long, so the process proceeds to step S3, where the predetermined time is extended within the upper limit time, for example to 10 seconds, and the ignition operation is started (step S4).

In step S6 above, if the temperature detected by the temperature sensor is not equal to or lower than the threshold temperature TL, the temperature of the stove burners 2a to 2c is high, and the time required from the user's ignition operation to the ignition determination of the stove burners 2a to 2c may be relatively short, so the process moves to step S7, where the predetermined time is shortened, for example to 5 seconds, and the ignition operation is started (step S4).

As described above, according to this embodiment, when installing the gas stove with grill A in a new installation location, the number of ignition operations and ignition errors can be reduced, reducing the workload of the operator. In addition, the specified time can be varied within a predetermined upper limit time depending on the combustion stop time of the stove burners 2a to 2c and the temperature of the stove burners 2a to 2c, thereby preventing explosive ignition and suppressing the occurrence of ignition errors, improving usability.

Figure 6 is a flowchart showing the variable processing of a predetermined time in another embodiment of the present invention.

In Figure 6, the specified time is variable within a predefined upper limit time, for example, within 16 seconds, depending on the ignition power of the stove burners 2a to 2c.

First, when the user performs an ignition operation, i.e., issues an ignition command (step S10), it is determined whether the ignition power of the stove burner 2a to 2c corresponding to the ignition operation is 1500 kcal/h or less (step S11). If the ignition power is 1500 kcal/h or less, it is assumed that the stove burner 2c has a relatively low ignition power and the process proceeds to step S12. In step S12, since the stove burner 2c has a low power, it is assumed that explosive ignition is unlikely to occur even if the specified time is extended, so the specified time is extended within the upper limit time, for example to 15 seconds, and the ignition operation is started (step S13).

If the ignition power is not 1500 kcal/h or less in step S11, it is determined whether the ignition power of the stove burner corresponding to the ignition operation is 3000 kcal/h or less (step S14). If the ignition power is 3000 kcal/h or less, the process proceeds to step S15. In step S15, the ignition power is greater than 1500 kcal/h and is 3000 kcal/h or less, and the ignition power is determined to be a medium-level standard-level burner 2a, so the specified time is set to a medium length within the upper limit time, for example 10 seconds, and the ignition operation is started (step S13).

If the ignition power is not 3000 kcal/h or less in step S14, the process proceeds to step S16. In step S16, since the ignition power is a relatively high-power stove burner 2b and a long predetermined time would make it easy for explosive ignition to occur, the predetermined time is shortened, for example to 5 seconds, and the ignition operation is started (step S13).

As described above, according to this embodiment, the specified time can be varied within a predetermined upper limit time depending on the ignition power of the stove burners 2a to 2c, which makes it possible to avoid explosive ignition while suppressing the occurrence of ignition errors, improving usability.

The ignition power does not necessarily have to be determined according to the maximum power of the stove burner. For example, a high-power stove burner and a standard-power stove burner may have the same ignition power.

The user can variably set the specified time as follows:

Figure 7(a) shows a portion of the grill cooking setting input unit 12, and Figure 7(b) shows a portion of the gas stove cooking setting input unit 13.

When the user himself/herself wishes to variably set the predetermined time, for example, he/she presses the "+" key 45a or "-" key 45b of the stove timer 45 of the gas stove cooking setting input unit 13 and the high-temperature stir-fry key 46 of the left stove simultaneously for 5 seconds or more to start the setting mode for varying the predetermined time.

In this setting mode, for example, the "+" key 47a and "-" key 47b of the grill timer 47 in the grill cooking setting input section 12 are operated to select the item number corresponding to the variable setting of the predetermined time (the item number is displayed on the grill timer 47). After selecting the item number, the "+" key 45a and "-" key 45b of the stove timer 45 in the gas stove cooking setting input section 13 are operated to set one of the numbers "01" to "15" (the predetermined time to be set on the stove timer 45 is displayed), thereby variably setting the predetermined time within the upper limit time, from 1 to 15 seconds, either individually or collectively, for each stove burner in 1-second increments.

Then, press the "+" key 45a or "-" key 45b of the stove timer 45 in the gas stove cooking setting input unit 13 and the high-temperature stir-fry key 48 on the right stove simultaneously for 5 seconds or more to end the setting mode for varying the specified time.

In the above embodiment, the installation state detection unit that detects that the gas stove A with a grill has been installed in a new installation location detects that the gas stove A has been installed in a new installation location when the battery is first set in the battery box after shipment. However, in another embodiment, when the gas stove A with a grill is installed in a new installation location, the installation state detection unit may detect that the gas stove A with a grill has been installed in a new installation location by performing a required operation.

As an example of this required operation, the installation in a new location can be detected by inserting a dry cell battery into the battery box while pressing the left burner rice cooking/water boiling key 49 or the right burner rice cooking/water boiling key 50 on the gas stove cooking setting input unit 13.

In another embodiment, the gas stove with grill A uses a commercial power source (100V power source), and the installation status detection unit that detects that the gas stove with grill A has been installed in a new installation location may be configured to detect that the gas stove with grill A has been installed in a new installation location when the gas stove with grill A is first connected to a commercial power source (100V power source) after shipment.

It goes without saying that the above-mentioned variable setting of the predetermined time by the user and the key operations required to detect that the gas stove with grill A has been installed in a new installation location are not limited to those described above.

Furthermore, the present invention is not limited to the embodiments shown in Figures 5 and 6 above, and some or all of them may be combined as appropriate.

(4) In the preferred embodiment of the present invention, for example, the specified time may be varied based only on the combustion stop time of the stove burner in Figure 5 , or the specified time may be varied by appropriately combining the combustion stop time of the stove burner or the detected temperature of the stove burner with the ignition power of the stove burner shown in Figure 6.

The specified time when there is no ignition history at the new installation location may also be set longer than other conditions (e.g., 15 seconds).

In another embodiment of the present invention, the specified time may be varied linearly within a predefined upper time limit in accordance with the burner burner combustion stop time, the detected temperature, the ignition power, etc.

2a to 2c Stove burner 3 Grill section
Reference Signs List 7a to 7c, 21 Temperature sensors 8a to 8c Heating state adjustment section 12 Grill cooking setting input section 13 Gas stove cooking setting input section 14a to 14c, 17a, 17b Spark plugs 15a to 15c, 18a, 18b Thermocouples 16a, 16b Grill burners 22a to 22e Igniters 28 Main solenoid valves 29 to 32 Flow control valves 40 Control section A Gas stove with grill

Claims (6)

A gas cooker comprising: a gas burner to which fuel gas is supplied; an ignition plug for igniting the gas burner; an igniter to which the ignition plug is electrically connected; an operation unit that is operated to ignite the gas burner; a flame detection sensor that detects a flame of the gas burner; and control means for controlling the supply of fuel gas to the gas burner and the igniter based on the ignition operation of the operation unit and the detection output of the flame detection sensor,
The control means includes a determination unit that determines whether or not the gas burner has been ignited based on a detection output of the flame detection sensor,
the control means, in response to an ignition operation of the operation unit, starts the supply of fuel gas to the gas burner and starts the drive of the igniter to cause a spark discharge in the ignition plug, stops the drive of the igniter if the determination unit determines that the gas burner has been ignited before a predetermined time has elapsed since the ignition operation, and stops the supply of fuel gas to the gas burner and stops the drive of the igniter if the determination unit does not determine that the gas burner has been ignited and the predetermined time has elapsed,
The gas cooker is characterized in that the control means varies the specified time within a predetermined upper limit time, and the gas cooker is provided with a plurality of gas burners with different ignition powers, the control means varies the specified time according to the ignition power of the gas burners, and the smaller the ignition power of the gas burners, the longer the specified time is. A gas cooker comprising: a gas burner to which fuel gas is supplied; an ignition plug for igniting the gas burner; an igniter to which the ignition plug is electrically connected; an operation unit that is operated to ignite the gas burner; a flame detection sensor that detects a flame of the gas burner; and control means for controlling the supply of fuel gas to the gas burner and the igniter based on the ignition operation of the operation unit and the detection output of the flame detection sensor,
The control means includes a determination unit that determines whether or not the gas burner has been ignited based on a detection output of the flame detection sensor,
the control means, in response to an ignition operation of the operation unit, starts supplying fuel gas to the gas burner and starts driving the igniter to cause a spark discharge in the ignition plug, stops driving the igniter if the determination unit determines that the gas burner has been ignited before a predetermined time has elapsed since the ignition operation, and stops supplying fuel gas to the gas burner and stops driving the igniter if the determination unit does not determine that the gas burner has been ignited and the predetermined time has elapsed,
A gas cooker characterized in that the control means varies the specified time within a predetermined upper limit time, and the control means is equipped with a timing unit that measures the combustion stop time of the gas burner, and the control means varies the specified time according to the combustion stop time, and the longer the combustion stop time, the longer the specified time is. A gas cooker comprising: a gas burner to which fuel gas is supplied; an ignition plug for igniting the gas burner; an igniter to which the ignition plug is electrically connected; an operation unit that is operated to ignite the gas burner; a flame detection sensor that detects a flame of the gas burner; and control means for controlling the supply of fuel gas to the gas burner and the igniter based on the ignition operation of the operation unit and the detection output of the flame detection sensor,
The control means includes a determination unit that determines whether or not the gas burner has been ignited based on a detection output of the flame detection sensor,
the control means, in response to an ignition operation of the operation unit, starts supplying fuel gas to the gas burner and starts driving the igniter to cause a spark discharge in the ignition plug, stops driving the igniter if the determination unit determines that the gas burner has been ignited before a predetermined time has elapsed since the ignition operation, and stops supplying fuel gas to the gas burner and stops driving the igniter if the determination unit does not determine that the gas burner has been ignited and the predetermined time has elapsed,
The gas cooker is characterized in that the control means varies the specified time within a predetermined upper limit time, and is provided with a setting operation unit that is operated to set the specified time, and the control means varies the specified time in accordance with the setting operation of the setting operation unit. A gas cooker comprising: a gas burner to which fuel gas is supplied; an ignition plug for igniting the gas burner; an igniter to which the ignition plug is electrically connected; an operation unit that is operated to ignite the gas burner; a flame detection sensor that detects a flame of the gas burner; and control means for controlling the supply of fuel gas to the gas burner and the igniter based on the ignition operation of the operation unit and the detection output of the flame detection sensor,
The control means includes a determination unit that determines whether or not the gas burner has been ignited based on a detection output of the flame detection sensor,
the control means, in response to an ignition operation of the operation unit, starts supplying fuel gas to the gas burner and starts driving the igniter to cause a spark discharge in the ignition plug, stops driving the igniter if the determination unit determines that the gas burner has been ignited before a predetermined time has elapsed since the ignition operation, and stops supplying fuel gas to the gas burner and stops driving the igniter if the determination unit does not determine that the gas burner has been ignited and the predetermined time has elapsed,
The control means varies the specified time within a predetermined upper limit time, and is provided with an installation state detection unit which detects when the gas cooker is installed in a new installation location, and the control means varies the specified time based on the detection output of the installation state detection unit, and the gas cooker is characterized in that the control means makes the specified time longer than the specified time thereafter until the judgment unit first judges that the gas burner has been ignited by the ignition operation when the gas cooker is installed in a new installation location. The gas cooker according to claim 4, characterized in that the power source of the control means is a replaceable battery loaded into the battery loading section or a commercial power source (100V power source), and the installation status detection section detects that the battery has been installed in a new installation location when it is first loaded into the battery loading section or when it is first connected to the commercial power source (100V power source). A gas cooker comprising: a gas burner to which fuel gas is supplied; an ignition plug for igniting the gas burner; an igniter to which the ignition plug is electrically connected; an operation unit that is operated to ignite the gas burner; a flame detection sensor that detects a flame of the gas burner; and control means for controlling the supply of fuel gas to the gas burner and the igniter based on the ignition operation of the operation unit and the detection output of the flame detection sensor,
The control means includes a determination unit that determines whether or not the gas burner has been ignited based on a detection output of the flame detection sensor,
the control means, in response to an ignition operation of the operation unit, starts supplying fuel gas to the gas burner and starts driving the igniter to cause a spark discharge in the ignition plug, stops driving the igniter if the determination unit determines that the gas burner has been ignited before a predetermined time has elapsed since the ignition operation, and stops supplying fuel gas to the gas burner and stops driving the igniter if the determination unit does not determine that the gas burner has been ignited and the predetermined time has elapsed,
The control means varies the specified time within a predetermined upper limit time, and a plurality of the gas burners are arranged on the top plate of the gas cooker, and the control means varies the specified time according to the position of the gas burner on the top plate, so that the farther the position of the gas burner is from the user, the longer the specified time is.

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