JP7713367B2 - Gas stove - Google Patents

Description

The present invention relates to a gas stove that uses a battery as a power source. In particular, the present invention relates to a gas stove that monitors the output voltage of the battery.

Gas stoves that use batteries as a power source have been provided by making the device pulse-driven and improving its performance. For example, there is a gas stove that has a stepping motor as a pulse-driven load, and the stepping motor adjusts the opening of a flow control valve installed in the gas supply path. In this type of gas stove, if the stepping motor is unable to be driven due to a drop in the battery output voltage after the stepping motor opens the flow control valve to start burning in the burner, the flow control valve will not be able to adjust the amount of burning in the burner, and cooking will fail. For this reason, it has been proposed to provide a voltage detection means that detects the battery output voltage, and to check whether the detected voltage of the voltage detection means when the battery output voltage is applied to one of the stator windings of the stepping motor by a switching means before starting to drive the stepping motor is equal to or lower than a predetermined reference voltage, and to prohibit the driving of the stepping motor if the detected voltage is equal to or lower than the reference voltage (for example, Patent Document 1).

Incidentally, gas stoves are equipped with various electrical devices (electrical loads of the power source) other than the stepping motor that drives the flow control valve as electrical devices that use batteries as their power source. For example, they are equipped with an igniter that ignites the burner and a speaker that notifies the operating status by voice, and some of these electrical devices may be operated in parallel with each other.

For example, when the burner is ignited, the stepping motor may be driven to open the flow control valve in parallel with the driving of the igniter. Also, if any abnormality occurs during the burner's combustion (temperature control) operation, a warning may be issued from the speaker in parallel with the closing of the flow control valve.

Because the internal resistance of a battery changes with the current value, when multiple electrical devices with large loads such as those mentioned above are driven in parallel and the current value becomes large, the burden on the power supply also increases, resulting in a large drop in the battery's output voltage. In addition, the internal resistance of a battery varies depending on the usage environment and deterioration over time, and the lower the temperature and the lower the remaining battery charge, the higher the internal resistance becomes and the greater the drop in the battery's output voltage. Furthermore, the internal resistance of a battery varies depending on the type of battery, and the resistance value of electrical devices varies due to individual differences. For this reason, the maximum value of the drop in the battery's output voltage when electrical devices are driven is predicted, and a reference voltage is set with a certain amount of margin.

However, if a reference voltage is set with a margin of error to allow each electrical device to be driven, as in the past, there is a problem that the burner combustion is prohibited even when multiple electrical devices can actually be driven in parallel. In addition, it is possible to check the battery output voltage by driving multiple electrical devices before igniting the burner, but if the stepping motor is pulse-driven, the battery output voltage will fluctuate greatly. Therefore, if a speaker is driven together with the stepping motor, there is a problem that the battery output voltage cannot be detected accurately and unwanted sound will be output from the speaker.

JP 2003-339195 A

The present invention aims to solve the above problems, and its purpose is to provide a gas stove that is easy to use and can accurately detect the battery output voltage.

According to the present invention,
Batteries and
a burner for burning a fuel gas supplied thereto to heat the food to be cooked;
a flow rate control valve for controlling the amount of fuel gas supplied to the burner;
a stepping motor that drives a flow rate adjusting valve, which is an electrical load powered by a battery, and an alarm that outputs audio information;
A control unit that controls the operation of the electric load and monitors the output voltage of the battery when the electric load is operated,
A gas stove is provided in which, before igniting the burner, the control unit drives the stepping motor with DC current and causes the alarm to output audio information in an inaudible frequency range, thereby performing an initial voltage check to monitor the battery output voltage.

According to the gas stove, before the burner is ignited, an initial voltage check is performed to monitor the battery output voltage by driving the stepping motor and the alarm, which may be driven in parallel while the gas stove is operating, so that a drop in the actual battery output voltage when multiple electrical devices are operated can be detected. Furthermore, according to the gas stove, in the initial voltage check, the stepping motor is driven with DC and audio information in the inaudible frequency range is output from the alarm, so that fluctuations in the battery output voltage can be reduced and unnecessary audio output can be prevented. As a result, according to the gas stove, the battery output voltage that is appropriate for the actual usage conditions can be accurately detected before cooking begins, without causing the user to feel uncomfortable due to audio.

Preferably, in the gas stove,
The burner is an electric load that is powered by a battery.
The control unit further drives the igniter during the initial voltage check.

According to the gas stove described above, the initial voltage check also drives the igniter, which may be driven in parallel with the stepping motor and alarm while the gas stove is running, so that the battery output voltage appropriate to the actual usage conditions can be detected more accurately.

As described above, the present invention makes it possible to accurately detect the battery output voltage before the burner is ignited, and to provide a gas stove that is easy to use.

FIG. 1 is a schematic perspective view showing an example of a gas stove according to an embodiment of the present invention. FIG. 2 is a block diagram showing an example of a gas stove according to an embodiment of the present invention. FIG. 3 is a time chart showing an example of the operation of the gas stove according to the embodiment of the present invention.

Hereinafter, a gas stove according to an embodiment of the present invention will be specifically described with reference to the drawings.
FIG. 1 is a schematic perspective view showing the external shape of a gas stove 1 according to the present embodiment. The gas stove 1 includes a stove body 2 and a top plate 3 covering the upper surface of the stove body 2. Inside the stove body 2, left and right stove burners 10L and 10R are provided with their upper parts protruding from the top plate 3, and on the top plate 3, a trivet 4L is placed so as to surround the left stove burner 10L, and a trivet 4R is placed so as to surround the right stove burner 10R. Then, with a cooking vessel such as a pot placed on the trivets 4L and 4R, the cooking vessel is heated from below by the left and right stove burners 10L and 10R, so that the food in the cooking vessel can be heated and cooked. The gas stove 1 may have a grill inside.

Operation knobs 6L, 6R are mounted on the front side of the stove body 2, which are operated by the user to turn on and off the left and right stove burners 10L, 10R and adjust the flame strength. A sound output hole 9h is formed in the center of the front of the stove body 2, allowing audio information to be output from a speaker (alarm) 30 (see Figure 2) built into the stove body 2. Furthermore, a power switch 9 for the gas stove 1 is mounted in the upper right corner of the front of the stove body 2. In this specification, the depth direction when viewing the gas stove 1 from the front is referred to as the front-rear direction, the width direction is referred to as the left-right direction, and the height direction is referred to as the up-down direction.

Figure 2 is a block diagram showing the internal structure for controlling the operation of the gas stove 1. Fuel gas is supplied to the left and right stove burners 10L and 10R from a gas pipe 20, which is a gas supply path. The gas pipe 20 is a single pipe on the upstream side, which branches into multiple pipes downstream of the main valve 21 and is connected to the left stove burner 10L and the right stove burner 10R. The main valve 21 is composed of an electrically operated opening and closing valve and is connected to the control unit 50, which will be described later.

The gas pipe 20 connected to the left burner 10L is provided with an electromagnetic safety valve 22L and a flow rate adjustment valve 23L, in that order from the upstream side. Similarly, the gas pipe 20 connected to the right burner 10R is provided with an electromagnetic safety valve 22R and a flow rate adjustment valve 23R. The electromagnetic safety valves 22L and 22R are each configured as an energized holding type electromagnetic valve, and are held open by continuously energizing an electromagnet (not shown), and are closed by cutting off the energization. The electromagnetic safety valves 22L and 22R are connected to a control unit 50. The flow rate adjustment valves 23L and 23R are driven by stepping motors 24L and 24R, respectively, and the stepping motors 24L and 24R are connected to the control unit 50.

The left and right burners 10L, 10R each have a temperature sensor 11L, 11R in the center, and spark plugs 12L, 12R and flame detection sensors 13L, 13R around them. The temperature sensors 11L, 11R and flame detection sensors 13L, 13R are connected to a control unit 50, and the spark plugs 12L, 12R are connected to a shared igniter 33. The igniter 33 is an electrical device that generates a high voltage to generate a spark discharge in the ignition plugs 12L, 12R, and the igniter 33 is connected to the control unit 50. The operation knobs 6L, 6R and speaker 30 on the front of the stove body 2 are also connected to the control unit 50.

The gas stove 1 is equipped with a control unit 50, which is an electronic circuit unit for controlling the operation of the gas stove 1. The control unit 50 is equipped with a microcomputer (hereinafter referred to as a microcomputer) 51, which is equipped with a CPU, memory, a timer, etc., and is capable of executing various processes according to programs stored in the memory. The control unit 50 also includes an operation switch circuit 41 that generates operation signals of the operation knobs 6L and 6R and inputs them to the microcomputer 51, a valve drive circuit 42 that energizes and drives the main valve 21 according to a control command from the microcomputer 51, an electromagnetic valve drive circuit 43 that energizes and drives the electromagnetic safety valves 22L and 22R according to a control command from the microcomputer 51, a motor drive circuit 44 that drives the stepping motors 24L and 24R according to a control command from the microcomputer 51, and a spark plug ignition circuit 45 that ignites the ignition plugs 12L and 12R. The gas stove includes an igniter driving circuit 45 that energizes the igniter 33 that generates the spark discharge according to a control command from the microcomputer 51, a speaker driving circuit 46 that applies an audio signal of a predetermined frequency to the speaker 30 according to a control command from the microcomputer 51 to output audio information, a power supply circuit 47 that boosts or stabilizes the voltage from the battery 60 that is the power supply for the gas stove 1 to supply power to the microcomputer 51, etc., and a battery voltage monitoring circuit 48 that monitors the output voltage of the battery 60. The microcomputer 51 may be composed of a control microcomputer that executes combustion control, and an operation microcomputer that detects the operation of the operation knobs 6L and 6R and outputs an audio signal to the speaker 30.

When the user turns on the power switch 9, the power supply circuit 47 supplies power from the battery 60 to the microcomputer 51 and other drive circuits, enabling each drive circuit to energize the main valve 21, the electromagnetic safety valves 22L and 22R, the stepping motors 24L and 24R, the speaker 30, and the igniter 33. The power supply circuit 47 also applies a voltage corresponding to the voltage of the battery 60 to the battery voltage monitoring circuit 48, which monitors the output voltage of the battery 60 using the voltage provided by the power supply circuit 47 and outputs a signal based on the output voltage to the microcomputer 51. When the output voltage of the battery 60 falls below a predetermined reference voltage, the microcomputer 51 prohibits the driving of the electromagnetic valve driving circuit 43 and the motor driving circuit 44, and drives the speaker driving circuit 46 to notify predetermined audio information from the speaker 30. In this embodiment, a battery with a rated voltage of, for example, 3V in a new state is used.

Although not shown, the motor drive circuit 44 includes a power supply circuit capable of selectively generating direct current and pulses, and a switching circuit, and selects whether direct current or pulses are applied to the stepping motors 24L, 24R in response to a control command from the microcomputer 51. Specifically, when the power switch 9 is turned on and the microcomputer 51 starts up, a direct current is generated in an initial voltage check described below, and the stepping motor 24L is driven with the direct current to monitor the output voltage of the battery 60. If the output voltage of the battery 60 is then higher than a predetermined reference voltage, the stepping motors 24L, 24R are pulse-driven in response to the user's operation of the control knobs 6L, 6R. The peak current values in the direct current drive and pulse drive are set to be approximately the same.

The speaker driving circuit 46, in response to a control command from the microcomputer 51, applies a predetermined acoustic signal to the speaker 30, causing the speaker 30 to output audio information at frequencies in the audible range (generally 10-20 kHz) and inaudible range (generally 20 kHz or higher).

Next, the operation of the gas stove 1 of this embodiment will be described. In this embodiment, in consideration of the consumption of the battery 60, the multiple stepping motors 24L and 24R are set not to be driven in parallel during the operation of the gas stove 1. For this reason, in the initial voltage check performed when none of the stove burners are ignited, the igniter 33, one of the stepping motors 24L, and the speaker 30, which may be driven in parallel, are driven so as to be close to the load during the operation of the gas stove 1. However, if there are other electrical loads, they may also be driven in parallel. For example, if the gas stove 1 is equipped with communication devices for communicating with external devices (e.g., smartphones, wireless routers, range hoods) by radio waves or infrared rays, these electrical devices may also be driven in parallel in the initial voltage check. In addition, the electromagnetic safety valves 22L and 22R may be driven in parallel with the stepping motors 24L and 24R, so they may also be driven in the initial voltage check. However, the electromagnetic safety valves 22L, 22R are electrical devices with a small load, and the current value required to keep the electromagnetic safety valves 22L, 22R open is small, so the drop in the output voltage of the battery 60 when the electromagnetic safety valves 22L, 22R are driven is minor. Therefore, if the output voltage of the battery 60 is higher than the reference voltage in an initial voltage check in which an electrical device with a large load is driven without driving the electromagnetic safety valves 22L, 22R, the electromagnetic safety valves 22L, 22R can also be driven stably.

As shown in FIG. 3, when the user turns on the power switch 9, the power supply circuit 47 supplies power to the microcomputer 51 and each drive circuit, starting them up. The power supply circuit 47 then applies a voltage corresponding to the voltage of the battery 60 to the battery voltage monitoring circuit 48, and if the output voltage Vx of the battery 60 is higher than a predetermined appropriate voltage Vc (e.g., 2.68 V), i.e., if there is sufficient charge remaining in the battery 60, the battery voltage monitoring circuit 48 outputs a signal to the microcomputer 51 indicating this.

If the output voltage Vx of the battery 60 is higher than the appropriate voltage Vc, as shown in FIG. 3, the stepping motor 24L is driven by DC in response to a control command from the microcomputer 51, and audio information in the inaudible frequency range is output from the speaker 30. Furthermore, the igniter 33 is energized to apply a high voltage to the ignition plugs 12L and 12R. In this state, an initial voltage check is performed to determine whether the output voltage Vx of the battery 60 provided by the battery 60, which is monitored by the battery voltage monitoring circuit 48, falls below a predetermined reference voltage Vs (2.0V).

Although not shown, if the output voltage Vx of the battery 60 is equal to or lower than the reference voltage Vs during the initial voltage check, the stepping motors 24L, 24R may not be able to be driven during combustion of either of the stove burners 10L, 10R, and the opening of the flow control valves 23L, 23R may not be able to be adjusted. For this reason, the microcomputer 51 prohibits the driving of the electromagnetic safety valves 22L, 22R and the stepping motors 24L, 24R, and issues audio information in the audible frequency range from the speaker 30 to make the user aware of the need to change the battery.

On the other hand, if the initial voltage check finds that the output voltage Vx of the battery 60 is higher than the reference voltage Vs, the motor drive circuit 44, igniter drive circuit 45, and speaker drive circuit 46 are de-energized and the operation of the operation knobs 6L and 6R is awaited. Then, as shown in FIG. 3, for example, when the user operates the operation knob 6L to ignite the left burner 10L, the control command from the microcomputer 51 opens the main valve 21 and the electromagnetic safety valve 22L, and pulse-drives the stepping motor 24L to open the flow control valve 23L to a predetermined opening. Next, the control command from the microcomputer 51 energizes the igniter 33, applies a high voltage to the ignition plugs 12L and 12R, and executes the ignition process. At this time, for example, if the flame detection sensor 13L does not detect a combustion flame and ignition failure occurs, audio information in the audible frequency range is output from the speaker 30 in response to a control command from the microcomputer 51 to notify the user of the ignition failure.

For example, when the left burner 10L is burning and the user operates the control knob 6R to ignite the right burner 10R, the control command from the microcomputer 51 opens the electromagnetic safety valve 22R, opens the flow control valve 23R, and applies high voltage to the ignition plugs 12L and 12R in the same manner as described above, and the ignition process is executed. At this time, for example, when a predetermined notification is made from the speaker 30 about the cooking status of the left burner 10L, audio information in the audible frequency range is output from the speaker 30 in response to a control command from the microcomputer 51. Therefore, in the gas stove 1 of this embodiment, the above state is the maximum load state in which electricity is applied to all electrical appliances that are driven in parallel.

As can be seen from the change in the output voltage of the battery 60 during the ignition process of the left and right burners 10L and 10R in FIG. 3, when the stepping motors 24L and 24R are pulse driven, the output voltage of the battery 60 has a sawtooth-shaped voltage waveform that repeatedly drops and recovers as the output is turned on and off. In contrast, in the initial voltage check of this embodiment, the stepping motor 24L is driven by DC, so the power consumed by the motor drive circuit 44 and the stepping motor 24L is approximately constant, and the fluctuation in the output voltage of the battery 60 is small. Also, as shown in FIG. 3, in the initial voltage check, the stepping motor 24L is driven by DC and the igniter 33 is also driven in parallel, so that the current value increases, and the drop in the output voltage of the battery 60 increases. Also, even if the speaker 30 outputs audio information in the inaudible frequency range, the fluctuation in the output voltage of the battery 60 is small. As a result, the output voltage of the battery 60 can be accurately detected even when the stepping motor 24L and the speaker 30 are driven in parallel.

As described above in detail, according to this embodiment, before the left and right stove burners 10L, 10R are ignited, one of the stepping motors 24L, 24R, speaker 30, and igniter 33 that are driven in parallel while the gas stove 1 is in operation is driven to perform an initial voltage check to monitor the output voltage of the battery 60, so that it is possible to detect a drop in the output voltage of the battery 60 when multiple electrical appliances are actually driven in parallel. Therefore, it is possible to detect the output voltage of the battery 60 that matches the usage conditions of the gas stove 1. This eliminates the need to set a reference voltage with a margin that predicts the maximum value of the drop in the output voltage of the battery 60 when the electrical appliances are driven, and allows the reference voltage to be set with high accuracy, allowing the battery 60 to be used effectively.

In addition, according to this embodiment, in the initial voltage check, the stepping motor 24L is driven with DC and the speaker 30 is made to output audio information in the inaudible frequency range, so that fluctuations in the output voltage of the battery 60 can be reduced and unnecessary audio output can be prevented before the left and right stove burners 10L, 10R are ignited. In particular, in this embodiment, the igniter 33, which causes a large drop in the output voltage of the battery 60, is also driven in parallel with the stepping motor 24L and the speaker 30, so that the output voltage of the battery 60 that matches the actual usage conditions can be detected more accurately while suppressing fluctuations in the output voltage of the battery 60.

1 Gas stove 10L, 10R Stove burner 23L, 23R Flow control valve 24L, 24R Stepping motor 30 Speaker 33 Igniter 50 Control unit 60 Battery

Claims (2)

Batteries and
a burner for burning a fuel gas supplied thereto to heat the food to be cooked;
a flow rate control valve for controlling the amount of fuel gas supplied to the burner;
a stepping motor that drives a flow rate adjusting valve, which is an electrical load powered by a battery, and an alarm that outputs audio information;
A control unit that controls the operation of the electric load and monitors the output voltage of the battery when the electric load is operated,
A gas stove in which a control unit performs an initial voltage check to monitor the output voltage of the battery by driving a stepping motor with a direct current and outputting audio information in an inaudible frequency range from an alarm before igniting a burner. The gas stove according to claim 1,
The burner is an electric load that is powered by a battery.
The control unit is a gas stove that further drives the igniter during the initial voltage check.