JPS6273586A - Boiling controller for electric oven - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a boiling control device for an electric stove that detects the temperature at the bottom of the cooker and controls the amount of electricity supplied to a sheathed heater, particularly for controlling the size of the cooker or boiling temperature. This invention relates to controlling the amount of electricity applied to a sheathed heater efficiently regardless of the amount of hot water.

[Prior Art] Figure 6 is a plan view of a conventional electric stove, in which (1) is a sheathed heater and (2) is a temperature sensor that detects the temperature at the bottom of the cooker placed on the electric stove. The sensor, (3) is an automatic water boiling setting switch that adjusts the amount of heat generated by the sheathed heater (1), and (4) is a power switch.

In such an electric stove, energization of the sheathed heater (1) is started by inputting the power switch (4), and water is heated with the amount of heat set by the automatic water boiling setting switch (3). This temperature sensor (2) constantly detects the temperature at the bottom of the cooker, and the sheathed heater (1) outputs the set amount of heat based on the temperature detection signal of this temperature sensor (2). ) is controlled. Water filled in a cooking device such as a cooking device, a kettle, or a pot is heated and controlled until it boils by a sheathed heater (1) whose electricity is controlled.

[Problems to be Solved by the Invention] By the way, in the boiling control of conventional electric stoves, the power applied to the sheathed heater is reduced after the temperature sensor detects boiling. There was a problem of overboiling. Therefore, the cooker itself would heat up more than necessary, causing hot water to spill over, creating a danger and making it impossible to leave the electric stove unattended for long periods of time.

With conventional electric stoves like this, it was unthinkable to automatically boil water after a predetermined time, but it would be convenient if water could be automatically boiled at a predetermined time when cooking is about to start, allowing you to start cooking right away. This allows you to save wasted time on cooking.

This invention was made in order to solve this problem, and it is possible to automatically boil water after a set time and to perform stable boiling control even when the size of the cooker and the water level are different. The purpose is to obtain a boiling control device for electric stoves that can be used.

[Means for Solving the Problems] The boiling control device for an electric stove according to the present invention includes a timer time setting means, a maximum power energization means that performs control until just before reaching the boiling temperature, and a maximum power energization means that performs control until the maximum power energization ends. The present invention is characterized by the addition of two types of partial energization means that perform different controls depending on the magnitude of the gradient of temperature rise.

That is, the timer time setting means sets the timer time set by the reservation timer setting switch, and the maximum power supply means detects the gradient of temperature rise of water between predetermined temperatures and sets the maximum power until just before the boiling temperature is reached. The energization time is calculated and the maximum power is energized until the end of this duration.

Further, the first partial energization means is configured to control the temperature rise until the temperature rise reaches a boiling gradient, which is considered to be a boiling state, if the temperature rise gradient is smaller than the selected gradient determined as the selection point of the control method after the maximum power energization ends. Partial energization is carried out, and the second partial energization means carries out partial energization for a predetermined adjustment time that reaches a boiling state if the gradient of temperature rise is greater than the selected gradient after the end of maximum power energization.

The gradient of temperature rise determined by each of the energizing means is as follows:
It shows the heating characteristics of the sheathed heater depending on the size of the cooker and the amount of water, and by detecting the gradient of this temperature rise, it is possible to achieve good boiling control that is compatible with various types of cookers and different types of water. It becomes possible.

[Operation] According to the above configuration, energization of the sheathed heater is started after a preset timer time.

Then, before the boiling point, the power supplied to the sheathed heater is reduced, and if the temperature rise is small, partial energization control is performed until the temperature rise becomes so gentle that it is considered that the boiling point has been reached. be exposed.

In addition, when the temperature rise gradient is large, partial energization is controlled for a relatively short adjustment time to prevent overheating, and regardless of the size of the cooker or the amount of water, the bottom of the cooker is heated to the sheathed heater at almost the boiling point. The power supply is stopped.

According to such boiling control, boiling water is obtained after a set time, and the boiling state is maintained in a stable state without overheating the cooker.

[Embodiment] Fig. 1 is a circuit diagram showing an embodiment of the present invention, and Fig. 2 is a plan view of an electric stove according to the embodiment, and (1) to (4) are the same as the conventional device.

In the figure, (5) is the heat-sensitive element in the temperature sensor (2),
(6) is a microcomputer, which includes timer time setting means, maximum power energization means, first partial energization means, and second partial energization means, which are characteristic components of the present invention. Then, input the detection signal of the temperature sensor (2) and the output signal of the automatic water boiling setting switch (3).
(7) is a transistor, (8) is a photocoupler,
The transistor (7) is turned on and off based on a control signal output from the microcomputer (6), thereby operating the photocoupler (8) and controlling the energization of the sheathed heater (1).

(9) is a DC power supply, (10) is a thyristor that performs rectification, (11) is a commercial power supply, (12) is a buzzer that indicates when the water has boiled, and (50) is a reservation timer setting switch that sets the timer time. It is provided on the operation panel of the electric stove shown in FIG.

The embodiment has the above-mentioned configuration, and its operation will be explained based on the flowchart in FIG.

In addition, Figures 4 and 5 are graphs showing the state of water temperature when boiling control is performed. Figure 4 is for A route control in Figure 3, and Figure 5 is for B route control in Figure 3. The case is shown below.

In FIG. 3, first, in step (51), it is determined whether the reservation timer is set with the reservation timer setting switch (50), and if the reservation timer is not set, the process moves to step (13). If it has been set, the process moves to step (52). Then, step (
In step 52), it is determined whether or not the timer time has elapsed, and when the timer time has elapsed, the power switch (4) and the automatic water boiling setting switch (3) are turned on, and the process moves to step (13). Temperature detection is performed.

Next, in step (14), the heating power is maximized, that is, the maximum power is applied, and in step (15), when the power switch (4) is first turned on, temperature detection is performed in step (13), and automatic Water boiler setting switch (
When 3) is input, the heating power is maximized in step (14), that is, the maximum power is applied.

Next, in step (15), the temperature is detected H seconds (for example, 30 seconds) after the input of the automatic water boiling setting switch (3), and the process proceeds to step (16), where the detected temperature T is detected.
1 is higher than a predetermined temperature T2 (which is a branching temperature to be described later).

In the embodiment, this predetermined temperature T2 is set to approximately 45°C for performing C route control, and if T1≧T2, the process moves to step (37). ).

In step (17), the gradient of the temperature rise of the water between predetermined temperatures is detected and the duration of maximum power supply H281 is determined.
iJ, and as shown in Figure 3, the temperature T3
(e.g. 62.6°C) to T4 (e.g. 77.0'C)
) is first determined. This required time H1 is a value indicating the gradient of temperature rise, and based on this temperature rise gradient, taking into consideration the remaining heat of the sheathed heater (1), the maximum power is applied until just before the boiling temperature of 100°C is reached. Calculate the opening during continuation. And this duration 1”
2, the maximum power is continued as it is.

Next, in step (18), it is determined whether the gradient of the temperature increase is larger than the selection gradient determined as the selection point of the control method, and the required time H1 indicating the gradient of the temperature increase indicates the selection gradient. It is determined whether the predetermined time is longer than H3. In other words, if the temperature increase gradient is larger than the selection gradient, the control method using the first partial energization means (route A) is performed, and if it is larger, the control method using the second partial energization means (route B) is performed. .

Therefore, if H3≧H1, the process moves to step (29) where A route control is performed, and if H3 is smaller than H1, the process moves to step (19) where B route control is performed. This step (
In one), the heating time from temperature T4 is measured,
This heating time H4 is changed to the duration H2 in step (20).
A determination is made as to whether the time has passed. That is, in step (20), the heating time H is II! A determination is made as to whether or not the duration is greater than the town. If H2>H4, the process returns to step (19); if the town is H2S, the process returns to step (2).
Moving to step 1), partial energization is performed to reduce the heating power to A%, for example 70%.

In this route A control, since the temperature increase gradient is originally small, it takes time to reach the boiling temperature, so the temperature increase gradient is further detected and partial energization is performed until the boiling gradient that can be regarded as boiling@temperature is reached. That is, in step (23), the temperature of the cooking bottom is further detected, and then in step (24)
), measure the time H6 after partial energization.

In step (25), it is determined whether the time H6 after this partial energization is greater than a predetermined time value H7, and H
If 6<H7, return to step (24);
If it is 7, the process moves to step (26) and the temperature T6 at that time is detected.

Then, in step (27), it is determined whether the difference between the two detected temperatures, that is, T5-T5, is greater than the temperature T7 representing the boiling gradient. And T6-T5≦T7
If so, it is assumed that the temperature at the bottom of the cooker has reached a temperature corresponding to the boiling temperature, and a buzzer is sounded in step (28). on the other hand,
If T6-T5>T7, the process moves to step (33) and the temperature increase gradient is further detected.

In steps (33) to (36), the boiling gradient detection function described above is performed, and the newly detected detection temperature T
If the difference between 8 and the detected temperature T6 is smaller than the temperature T7 indicating the boiling gradient, the process moves to the stainless steel 28 and sounds the buzzer. If the temperature difference T8-T6 is larger than the temperature T7, the process returns to step (26) and the temperature increase gradient is further detected. This operation is repeated as many times as the temperature rise gradient reaches a boiling gradient, and only when the boiling gradient is reached is a buzzer alerting the user that the water has boiled. In addition, after the notification is given by the buzzer, the current is continued to be supplied with a small amount of power to maintain the temperature at 100'C, which is 400W in the embodiment.

Next, the second partial energization means (B route control) after maximum power energization will be explained.

In step (18), the temperature rise gradient is divided into cases where it is low and high, but when the gradient of temperature rise is larger than a predetermined value, that is, when H3≧H1, the process moves to step (29). The maximum power supply is continued for the duration F12 determined in step (17).

Then, after the duration time t12 has elapsed, step (30
), partial energization is performed to increase the heating power to A%, 70% in the example. In the case of route B control, since the temperature rise gradient is large, the time to reach the boiling temperature is extremely short and the time can be easily estimated, so the adjustment time H
After 7 hours, a buzzer sounds to indicate the end of boiling. Therefore, in step (31), the time H9 from the start of partial energization
is being measured, and this time 1-19 is step (32)
At , it is determined whether adjustment time H7 has been reached, and H
After 7 hours, or 30 seconds in the example, the buzzer will sound.

As shown in FIG. 5, when the gradient of temperature rise is large, boiling Il! The time to reach the temperature is extremely quick, and by ending the partial energization to raise the temperature before the boiling point, it is possible to prevent the cooking device from overheating and maintain a good boiling condition of the water.

Next, in the example, C route control is performed when the starting temperature when boiling water is high, and since the time for the water temperature to reach the boiling state is short, this C route control reduces the heating time at maximum power to Korean. It is controlled by the slope ratio.

In step (16), the detected temperature T1 is set to the predetermined temperature T2.
(45°C).
When 1≧T2, the process moves to step (37) and measures the required time H1o from temperature T9 to Tlo (temperature difference is Tll). Then, in step (38), the time H11 required for the temperature to rise by a predetermined temperature Tll from the temperature TIO is measured, and in step (39), aHlo and Hll are compared.

That is, in step (39), the slope ratio a is calculated for time. It is determined whether the value multiplied by
), and partial energization is performed to increase the hn thermal power to 70%. And after that, as mentioned before), the adjustment time is 17.
Part C'J is energized and then the buzzer sounds.

Also, if a H10>811, step (40)
and perform temperature detection again. Then, the time H12 during which the detected temperature T12 rises by the predetermined temperature T11
is measured in step (41).

Next, in step (42), the step (39)
Similarly, it is determined whether aH12 is greater than Hll, and if aH11≦H12, step (30)
, and perform partial energization. If aHll>HI3, the process returns to step (40) and temperature detection is performed again.

In this way, route C control is such that when the water temperature is high when the electric stove is input, electricity is applied at maximum power until the predetermined temperature increase gradient reaches a predetermined ratio, and after reaching the predetermined ratio, the water reaches the boiling point. Partial energization is performed only during the adjustment time.

[Effects of the Invention] As explained above, the present invention calculates the duration of maximum power application from the gradient of temperature rise, applies the maximum power during this duration, and after this is finished, the maximum power is applied depending on the magnitude of the gradient of temperature rise. In addition to boiling control that performs different types of partial energization, we also perform timer control that energizes the sheathed heater at a timer time, so water can be automatically boiled after a preset timer time. Since the temperature of this hot water is in an extremely stable boiling state, it is possible to obtain hot water satisfactorily without monitoring the hot water inside the cooker.

Therefore, it is possible to obtain a convenient electric stove with a reservation timer that can be used with peace of mind.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the boiling control device according to the present invention, FIG. 2 is a plan view of the electric stove of the embodiment, and FIG.
The figure is a 70-chart diagram showing the operation of the control device of this invention.
FIG. 4 is a graph showing the rise in water temperature due to route A control, FIG. 5 is a graph showing the rise in water temperature due to route B control, and FIG. 6 is a plan view of a conventional electric stove. In the figure, (1) is a sheathed heater, (2) is a temperature sensor, (3) is an automatic water heating setting switch, (4) is a power switch, (6) is a timer time setting means, a maximum power supply means, and (50) is a reservation timer setting switch. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] (1) In an electric stove boiling control device that detects the temperature at the bottom of the cooker and controls the amount of electricity supplied to the sheathed heater in order to boil water, the sheathed heater is activated at the timer time set by the reservation timer setting switch. a timer time setting means for starting energization; and a maximum power energization device that detects the gradient of water temperature rise between predetermined temperatures, calculates the duration of maximum power energization, and energizes the maximum power until the end of this duration. a first means for carrying out partial energization until the temperature increase gradient reaches a boiling gradient, which is considered to be a boiling state, if the temperature increase gradient is smaller than the selected gradient determined as the selection point of the control method after the maximum power energization ends; Partial energization means, and second partial energization means that performs partial energization for a predetermined adjustment time to reach a boiling state if the gradient of temperature rise is greater than the selected gradient after the end of maximum power energization. Features a boiling control device for electric stoves.