JPH0653096B2 - Electric kettle with timer - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electric pot, and more particularly to an electric pot with a timer.

(Prior Art) Generally, in a re-boiling type electric pot, water contained in a container is boiled with a heater, and after boiling, a warming heater is used to maintain the water at a predetermined temperature, and re-boil as needed. The hot water heater is turned on with a switch to reboil the hot water that is being kept warm.In this type of reboil type electric pot, the warming heater that keeps the hot water at a predetermined temperature is constantly controlled to be turned on and off. Therefore, for example, there is a problem that power is wasted even when hot water is not used for a long time such as when sleeping. In particular, in order to use hot water early in the morning, the hot water must be boiled at night, which inevitably increases power consumption. In order to solve this problem, an electric pot having a built-in timer is proposed in, for example, Japanese Patent Application Laid-Open No. 60-116317 so that the kettle can be operated after a desired period of time.

(Problems to be Solved by the Invention) However, in an electric pot provided with this type of timer, for example, in order to make hot water boil when waking up,
Since the user has to calculate the time to start energizing the heater from the current time and the wake-up time and set the operation time, for a user who is weak in operating electronic devices,
There are problems that the operation is very complicated and that hot water cannot be obtained at a desired time due to an erroneous operation.

Therefore, the present invention reduces unnecessary power consumption when the hot water of the electric pot is not used for a long time, and at the same time, enables a user who is weak in the operation of the electronic device to set the timer very easily. Is a technical issue.

(Means for Solving the Problem) As a means for solving the above-mentioned problems, the present invention, when the hot water of the electric kettle is not used for a long time in a day, is generally between meals, when going out, When sleeping, etc., and when these times are statistically viewed, they are constant to some extent,
And if the operating time of the timer, that is, the time from the setting of the timer to the start of energizing the heater is shorter than these average times, pay attention to the fact that there is no actual harm even if the boiling water starts a little earlier, , A time (for example, 3 hours, 6 hours, 12 hours) slightly shorter than the time corresponding to the average time when going out or going to sleep etc. is set at the time of manufacture as an operation time and fixed, and the time is fixed in advance. A timer that operates only for the operation time, that is, a reservation timer, a timer set switch that outputs a timer on signal that sets the reservation timer to an on state, and the reservation timer that is output by operating the timer set switch. And the reservation timer after the fixed operation time elapses from the time point when the timer-on signal is received as a starting point. The output to the heater-on signal is obtained so as to provide a control means for turning on the heater driving circuit.

(Operation) In the electric pot according to the present invention, when the user presses the timer set switch 12 during its operation, the control means 16 operates the reservation timer Ta in response to the timer-on signal output from the user, and the heater drive circuit. Turn off 10 and 11 to keep the heater in a stopped state. After the reservation timer starts operating, when a predetermined time (for example, 6 hours) preset in the reservation timer Ta elapses from the start of the operation,
A heater-on signal is output from the reservation timer Ta, and the control means 16 receives the heater-on signal and causes the heater 16 to drive the heater driving circuit 1.
In order to operate 0 and 11, the energization of the heaters 4 and 5 is started, and the boiling water operation is performed. That is, according to the present invention, by pressing the timer set switch 12 once, the energization of the heater is automatically stopped for a fixed time set in advance, and after the set time elapses, water heating is performed.

(Example) Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an electric pot according to the present invention, which is provided with an inner container 3 inside the exterior body 2, and a water heater 4 and a heat retaining heater 5 are provided at the bottom of the inner container 3. . Further, the cover body 6 is provided with a steam discharge hole 7, and the steam discharge hole 7 communicates with the internal space S of the inner container 3 via a steam passage 8. A temperature detecting element T, which is a thermistor, is provided on the outer surfaces of the vapor passage 8 and the inner container 3.
H ₁ and TH ₂ are provided, and the temperature detecting element TH ₁ detects the temperature of the steam passing through the steam passage 8 and outputs the temperature detecting element TH 1.
₂ is configured to indirectly detect the hot water temperature via the inner container 3.

The heaters 4 and 5 and the temperature detecting elements TH ₁ and TH ₂ are connected to the control device of the circuit shown in FIG. 2, and the control device operates according to the flow chart shown in FIG.

As shown in FIG. 2, the control device basically has a drive circuit 11 for driving the water heater 4, a drive circuit 10 for driving the heat retention heater 5, a reservation timer Ta, and a control means 1.
6 and a timer set switch 12, and the water heating heater 4 and the heat retention heater 5 constitute the drive circuits 11 and 10 relays 24 and 2.
It is connected to the AC power supply 20 via the contacts 24a, 26a of the six.

In the figure, 21 is a power transformer, 22 is a rectifier circuit, and 27, 2
8 is a protection diode, 31 and 32 are comparators, and in the series circuit of the temperature detecting element TH ₁ and the resistor R ₁ , the terminals S ₁ and S ₂ provided in the microcomputer 30 connect the resistors R ₁₁ and R ₁₂ respectively. The temperature detection element TH ₁ and the resistors R ₁ , R ₁₁ and R ₁₂ are connected together to change the voltage input to the comparison input terminal 2a of the comparator 31. Therefore, in the comparator 31, by inputting a constant voltage from the reference input terminal 2b and changing the input voltage from the other comparison input terminal 2a, the vapor temperature above and below the two set temperatures (−20 ° C., 70 ° C.) Is determined.

Series circuit of temperature detecting element H ₂ and resistance R ₄ , and resistance R
_The connection points c and d of the series circuit of ₅ and the resistor R ₆ are connected to the comparison input terminal 2c and the reference input terminal 2d of the comparator 32, respectively, and the output terminal f of the comparator 32 is connected to the microcomputer 30. The terminals S ₃ and S ₄ of the microcomputer 30 are connected to the circuit having the temperature detecting element TH ₂ via resistors R ₁₃ and R ₁₄ , respectively. Therefore, also in the comparator 32, as in the case of the comparator 31, a constant voltage is input from the reference input terminal 2d, and a different voltage is input from the comparison input terminal 2c depending on the hot water temperature, with respect to the set temperature (-20, 70 ° C). The top and bottom are discriminated.

Hereinafter, the control operation of the electric pot 1 configured as described above
A description will be given according to the flowchart in the figure.

When the power source is turned on in step 1, the voltage of the AC power source 20 is dropped by the transformer 21, and the voltage transformed into the direct current by the rectifier circuit 22 has the microcomputer 30 and the temperature detection elements TH ₁ and TH ₂ . Applied to the circuit.

Next, in step 2 and step 3, the temperature detecting element T is supplied by a signal from the microcomputer 30.
It is determined whether or not the temperatures detected by H ₁ and TH ₂ are -20 ° C. or lower, and it is determined whether or not the circuit having these is disconnected. When the detected temperature is -20 ° C or lower,
It is considered that the wire is broken, and an abnormality is notified in step 201.

Then, in step 4, the height of the liquid level in the inner container 3 is detected. This is done by providing electrodes in exposed states at different heights of the liquid level gauge (not shown) and the inner container 3, and measuring the electrical resistances of these electrodes. That is, when the amount of water is below a predetermined level, one of the electrodes is located in the atmosphere, and the electric resistance between them is infinite.

If the amount of water is below the predetermined level, step 40
In step 1, a buzzer is notified, and in step 402, water supply is notified. After that, the amount of water is checked again in step 403, and if the water is not replenished to a predetermined level or higher, the process returns to step 402, and steps 402,
The operation of 3 is repeated. When the water supply above the predetermined level is confirmed, the process proceeds to step 5.

In step 5, it is determined whether the timer set switch 12 is off, that is, whether it is operated by the user. The reservation timer Ta is incorporated in the microcomputer 30 shown in FIG.

If it is determined in step 5 that the user has operated the timer set switch 12, the timer set switch 12
In response to the signal from the control means 16, the control means 16 informs the user with a buzzer (step 501) and then shifts to the timer operation (step 502). When the timer operation starts, the control means 16 starts the reservation timer Ta (step 50).
3) At the same time, the heater driving circuit is turned off to stop the energization of the boiling water heater 4 and the warming heater 5.

While the reservation timer Ta is operating, the control means 16 constantly operates the timer set switch 12 (step 504).
And determination of the elapsed time after the start of the timer operation (step 50
5), and unless the user operates the timer set switch 12 after starting the timer operation, the loop of steps 504 and 505 is repeated until the operation time set in the reservation timer Ta, that is, 6 hours, elapses. Repeatedly, the reservation timer Ta is maintained in the ON state.

While this timer is operating, that is, when the reservation timer Ta has progressed to the middle (for example, the state where it has advanced to 4 hours),
When the user presses the timer set switch 12, the control means 16 determines in step 504 that the timer set switch 12 of the reservation timer Ta is on, releases the reservation timer, and returns to step 2. Also, after starting the timer operation,
When it is determined in step 505 that the time set in advance in the reservation timer, that is, 6 hours, has passed, the process proceeds to step 7, and after the buzzer is notified, the water heating operation is started, and step 9
From step to step 17, the boiling water operation is performed.

Further, when it is confirmed in step 5 that the timer set switch 12 is in the off state, the process proceeds to step 6, in which the temperature detecting element TH ₂ detects the hot water temperature, and the temperature is 7
If it is 0 ° C. or less, the operation proceeds to step 7, the buzzer is notified, and the water boiling operation is started. If the water temperature is 71 ° C. or more, the operation proceeds to step 18, and steps 18 to 29.
The heat retention operation of is started.

When the timer set switch 12 is turned on during the water heating operation and the heat retaining operation, the steps 14 to 50 are performed.
Then, the timer operation is performed.

In the boiling water operation, the transistor 23 is activated by the signal from the microcomputer 30, and the relay 2
The water heating operation by the water heater 4 is started to turn on the contact 24a of No. 4 (step 8), and the timer (Tb)
Starts (step 9). This timer (Tb) is a time Tb (= T ₁ + t ₁ ) obtained by adding the margin time t ₁ to the time T ₁ required for boiling at the bottom voltage state by filling the inner container 3 with water at room temperature.
Is set to 30 minutes in this embodiment.

In this boiling water operation as well, similarly to steps 2 to 5, it is judged whether the temperature detection elements TH ₁ and TH ₂ are good or bad and whether or not the amount of water is appropriate (steps 10 to 12). If there is no abnormality, the reservation timer Ta is turned off. It is determined again whether or not there is (step 14), and it is determined whether or not 30 minutes have elapsed after the timer (Tb) was started. If not completed, the process proceeds to step 16 where the steam passage 8 is provided. It is determined whether or not the vapor temperature detected by the temperature detecting element TH ₁ is 69 ° C. or higher. That is, it is determined whether or not the hot water has boiled.

If the steam temperature is 69 ° C or lower, return to step 10 again, and then step 1 until the steam temperature becomes 69 ° C or higher.
The loop of 0 to step 16 is repeated. However, if 30 minutes elapses until the steam temperature reaches 69 ° C., it is considered that the temperature detection device TH ₁ is broken, and Step 1
From 5 to step 151, the abnormality is notified here, and the transistor 23 is operated by the signal from the microcomputer 30 to contact the contact 24 of the relay 24.
Turn off a, and cut off the power supply to the water heater 4. As a result, even if the temperature detecting element TH ₁ fails or other devices fail, the temperature of the electric pot 1 does not continue to rise and damage to the body of the electric pot 1 can be prevented.

When it is confirmed that the steam temperature has reached 69 ° C., the process proceeds from step 16 to step 17, the buzzer is notified, and the process proceeds to step 18 to start the heat retention operation.

When the warming operation is started, the transistor 25 is operated by a signal from the microcomputer 30, the contact 26a of the relay 26 is turned on, the warming heater 5 is energized, and the hot water is kept warm. Even in this heat retention operation, the temperature detection elements TH ₁ , TH ₂
And the amount of water are checked (steps 19 to 21), and if there is an abnormality, the process proceeds to steps 191, 211, and 401 to notify the abnormality, and the microcomputer 3
The transistor 25 is operated by a signal from 0 to turn off the contact 26a of the relay 26 to cut off the power supply to the heat retention heater 5.

Then, in step 22, it is determined whether the hot water temperature is 70 ° C. or higher, and if it is 70 ° C. or higher, the process proceeds to step 23, and it is determined whether or not a reboil switch (not shown) is in the ON state.
If the reboil switch is off, the process returns to step 19, and the loop from step 19 to step 23 is repeated. During this time, when the temperature of the hot water drops to 69 ° C. or less, the process returns from step 22 to step 7 to start the boiling water operation.

When it is determined in step 23 that the reboil switch is in the on state, the buzzer is notified in step 24, the process proceeds to step 25, and the reboil operation is started. Then, the water heating heater 4 is driven by the signal from the microcomputer 30 to start the water heating operation, and the timer (Tc) is started at step 26. This timer (Tc)
Is the time Tc (= T ₂ + which is the time required for boiling (“ ₂ ”) plus the allowance time (t ₂ ) with the inner container filled with 70 ° C. hot water.
At t ₂ , Tc is set to 10 minutes in this embodiment.

Then, in step 27, it is judged whether or not the set time of the timer (Tc) has expired, and if it is within 10 minutes, step 2
In step 8, it is determined whether the vapor temperature detected by the temperature detecting element TH ₁ is 69 ° C. or higher. And the steam temperature is 6
If it is not higher than 9 ° C., the process returns to step 27. During this time, when it is determined in step 27 that the timer (Tc) has expired, the process proceeds to step 271, in which an abnormality is notified and a signal from the microcomputer 30 turns off the contact 24a to cut off the power supply to the water heater. To do.

In step 27, the temperature detection element TH is set within 10 minutes.
_When it is confirmed by ₁ that the steam temperature is 69 ° C. or higher, the process proceeds to step 29, the buzzer is notified, and the contact 24a
Is turned off, the boiling water operation is stopped, and the process returns to step 18.

In addition, in the said Example, the required and sufficient boiling times at the time of boiling water and reboiling were set to 30 minutes and 10 minutes, respectively, but it is not restricted to this.

(Effects of the Invention) As is apparent from the above description, the electric pot according to the present invention can set the timer only by pressing the timer set switch, and therefore the operation is simple, and when the timer is set, the current time is set. Since it is not necessary to set the timer in consideration of the wake-up time and the like, there is no malfunction due to erroneous operation or calculation error, and at the same time when the timer is set, the heater is turned off for a predetermined time. When hot water is not used for a long time, for example, it is possible to eliminate unnecessary power consumption when going to sleep, and after a lapse of a predetermined time, the heater is energized to start boiling water. Can be obtained. Furthermore, since the heater is de-energized when sleeping, it is possible to prevent accidents such as fires and other accidents and to ensure safety.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of an electric pot according to the present invention,
FIG. 2 is a circuit diagram of the control device, and FIG. 3 is a flowchart diagram of the operation. 3 ... Vessel, 4 ... Hot water heater, 5 ... Heat insulation heater, 7 ... Steam discharge hole, 8 ... Steam passage, 12 ... Timer set switch, 10, 11 ... Heater drive circuit, T
a ... Reservation timer, 16 ... Control means, TH ₁ , TH ₂ ...
... Temperature detecting element.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiya Kobe 1-20-5 Tenma, Kita-ku, Osaka-shi, Osaka, Japan Zojirushi Mahobin Co., Ltd. No. 5 within Zojirushi Mahobin Co., Ltd. (56) Reference JP-A-60-116317 (JP, A) JP-A-60-170381 (JP, A) Actual development S60-171220 (JP, U) Actual development A 59-181957 (JP, U) Actually opened 60-160357 (JP, U) Actually opened 57-194425 (JP, U) Actually opened 59-105421 (JP, U) Actually opened 60-80727 (JP, U)

Claims (1)

[Claims] 1. A reservation timer that operates for a fixed operating time in an electric pot provided with a container for containing water, a heater for heating the water in the container, and a heater drive circuit for driving the heater. , A timer set switch that outputs a timer on signal that sets the reservation timer to an on state, and a timer on signal that is output by operating the timer set switch turns the reservation timer on and the reservation timer turns on. An electric pot with a timer provided with a control means for turning on the heater drive circuit by a heater on signal output after a lapse of the fixed operation time from a time point when the signal is received as a starting point.