JPH0415015A - Pressure heating device - Google Patents

Abstract

PURPOSE:To enable safe handling by detecting the point of time when a pressure adjusting means starts operating by a gas sensor, and automatically deciding the amount of time from heating to steaming according to the detected time. CONSTITUTION:A timer knob 3 and an auto-key 4 on a console panel 2 are connected to a control portion 11 to perform setting of heating time and a command for a heating category. A gas sensor 13 is disposed in an air duct formed by a cover handle 8 and a main body 1, and adapted to detect the surplus steam and gas, discharged from a weight 5 through an opening of a nozzle 14, when a pressure indicating pin 10 is raised. That is, when heating is started and the pressure in a pressure casing is increased so that the weight starts moving, the steam leaks out of an opening of the nozzle 14 so that the humidity near the gas sensor 14 is suddenly heightened. Such a change is digital and a humidity sensor has good sensitivity so as to detect it. At the time of automatic heating, the time required from the start of heating to the detection point of the sensor is counted by a control portion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a pressure heating apparatus such as a pressure cooker or a pressure cooker equipped with a sensor.

2. Description of the Related Art In general, there is a pressure cooker or a pressure cooker as a heater which aims to shorten the heating time by sealing the object to be heated and increasing the internal pressure using the steam pressure to raise the boiling point.

The heating mode using the pressure cooker or pressure cooker includes a rising mode until a pressure adjustment means such as a weight is activated;
It consists of a heating mode that maintains a constant internal pressure, and a steaming mode that stops heating and waits for the internal pressure to drop.

Among these heating modes, the time in steaming mode is difficult to predict for operators who do not know when normal pressure has been reached.

The heating time listed in cookbooks attached to household pressure cookers and the like is generally only the time required for the above-mentioned heating mode, and the time for the steaming mode is not specified.

In order to eliminate such troublesome operations, pressure cookers or pots are already on the market that are equipped with a pressure display bottle that indicates the current status.

As an example, electric pressure cooker 5R203P manufactured by Matsushita Electric Industrial ■
There is. This system uses a temperature sensor to detect the outside temperature of the bottom of the pot, and controls the power supply to the electric heater to maintain this temperature at a constant temperature, thereby maintaining the internal pressure of the pot at a certain value. That is, when the internal temperature of the pot is maintained at 120 degrees, the internal pressure of the pot is maintained at about 2 atmospheres.

There is a pressure indicator on the lid of the pot that increases when the internal pressure rises and decreases when it returns to normal pressure.

Depending on the position of this pressure display bottle, the internal pressure of the pot will drop and return to normal pressure, allowing you to know when it is safe to open the lid.

Problems to be Solved by the Invention However, it is unclear when the pressure will return to normal, that is, when the pressure display bottle will drop, and in the end, the pot will be occupied, making it impossible to predict the cooking time.

Therefore, the first object of the present invention is to provide a pressure heating device that can automatically calculate the time required for the steaming mode simply by setting a timer for the heating mode.

A second object is to provide a fully automatic pressure heating device that does not require a timer.

Means for Solving the Problems In order to achieve the first object, the present invention provides a gas sensor that detects the point in time when excess steam or gas discharged from the pressure regulating means starts to be discharged or a certain point thereafter. The first means for solving the problem is to provide a control unit that operates a timer means from that point on and stops power supply for a time calculated from the time required for detection.

Furthermore, in order to achieve the second object, the present invention provides a gas sensor that detects the point in time when excess steam or gas released from the pressure regulating means starts to be released or a certain point thereafter, and the time required to reach that point. The second means for solving the problem is to include a control unit that counts and continues/stops power supply to the heating means based on the counting.

Function: The pressure heating device of the present invention uses a gas sensor to detect excess steam or gas released from the pressure adjustment means, automatically calculates the required time for steaming mode, and safely returns to normal pressure. It can be terminated in this state.

In addition, since the time required for steaming mode strongly depends on the type and quantity of the object to be heated, the time required for steaming mode is calculated from the time when the pressure adjustment means starts operating by the gas sensor. The time can be determined automatically.

EXAMPLE Hereinafter, a pressure heating device according to an example of the present invention will be explained with reference to the drawings.

FIG. 2 is a perspective view of the main body of the pressure heating device according to an embodiment of the present invention, and the front of the main body 1 is equipped with an operation panel 2, which is part of a timer means for setting the heating time by manual heating. A timer knob 3 and an auto key 4 for automatically selecting the heating method depending on the type of the object to be heated and the category of heating are provided.

A weight 5 serving as a pressure adjustment means is provided at the center of the lid 6,
In order to maintain the internal pressure of the pressure vessel 7 built into the main body at a predetermined value, excess steam is discharged.◇The pressure display bottle 10 increases when the internal pressure of the pressure vessel 7 increases, If it has not risen yet, or if the pressure is reduced after heating and returns to normal pressure, it will perform a descending operation.

The lid handle 8 is a rod-shaped member with a hollow interior, and is fixed in the diametrical direction of the lid 6, with a weight 5 recessed in the center. By grasping the lid handle 8 and sliding the lid 6 in the radial direction, the lid 6 and the pressure vessel 7 can be sealed. Further, the discharged steam and gas are configured to pass through the hollow interior of the lid handle 8 and be guided to a gas sensor (not shown, see FIG. 1) in the main body 1.

9 is a handle for carrying the main body 1.

Now, FIG. 1 is a block diagram showing the configuration of a pressure heating device in one embodiment of the present invention.

An electric heater 18 serving as a heating means is disposed at the bottom of the pressure vessel 7, and power supply is controlled by the control unit 11 via a driver 12.

The timer knob 3 and auto key 4 on the operation panel 2 are connected to the control unit 11, and are used to set the heating time, command the heating category, and the like.

The gas sensor 13 is arranged in an air guide path formed by the lid handle 8 and the main body 1, and when the pressure display bottle 10 is raised, excess steam passes through the opening of the nozzle 14 and is discharged from the weight 5. or gas (arrow). 15 is its detection circuit.

Examples of the gas sensor 13 include a phase humidity sensor "Humiceram" manufactured by Matsushita Electric Industrial ■, an absolute humidity sensor "Neo Humiceram" gas sensor manufactured by Figaro, an absolute humidity sensor manufactured by Shibaura Denshi, and a thermal sensor manufactured by Matsushita Electric Industrial ■. Electric steam sensors, etc., and future equivalents are available.

Note that 16 is a rubber gasket that seals the lid 6 and the pressure vessel 7.

17 is a fan that cools the control section 11.

Next, an overview of the operation of this control system will be explained. Third
The figure is a time chart showing the steam near the gas sensor and the internal pressure of the pressure vessel. The fa1 diagram is the change in steam detected by the gas sensor, the TBT diagram is the movement of the internal pressure of the pressure vessel at this time, and the fC1 diagram is the fan represents the operation of

When heating begins, the temperature of the object to be heated within the pressure vessel begins to rise, and the internal pressure eventually begins to rise. However, since the weight blocks the nozzle opening, no steam exists near the gas sensor. This is the "stand up" mode.

Then, when the pressure inside the pressure vessel rises and the weight begins to move, steam leaks from the nozzle opening, and the humidity near the gas sensor increases rapidly. The change is digital, and the humidity sensor can detect point P with high sensitivity.

During automatic heating, the control unit counts the time T required from the start of heating to the detection point P of the sensor.

During manual heating, the timer means starts operating from point P. This is the heating mode.

When the predetermined heating time has elapsed, the power supply to the heating means is stopped, the internal pressure decreases and returns to normal pressure, and the time until the pressure display bottle decreases, that is, the steaming mode is entered.

Experiments have revealed that the time in the steaming mode has the same tendency as the rise time T1, which corresponds to the type and quantity of the object to be heated.

Table 1 shows some of the results of such experiments, in which the heating means was a magnetron with a high frequency output of 500 watts, the object to be heated was food, and the gas sensor was a pyroelectric type manufactured by Matsushita Electric Industrial. A steam sensor was used.

(Margins below) From the results of this experiment, it can be seen that the detection (T1) time of the gas sensor and the steaming time similarly tend to lengthen as the amount of the object to be heated increases.

It can also be seen that the slope differs depending on the type of object to be heated.

Therefore, by inputting the type of the object to be heated into the control unit, the amount of the object to be heated can be estimated from the detection time of the gas sensor, that is, the time T1 required for the rising mode, and this T+
Steaming time can be automatically calculated based on the value. That is, the steaming time T is determined by the following formula.

T=2T2+C K2: Coefficient that differs depending on the type of object to be heated C: Constant The steaming time for returning to normal pressure can be automatically ended through the calculation process.

Note that manual heating targets different types of objects to be heated, and since the heating mode time is freely set by the person operating the pot, the steaming mode time also varies. From the experimental results, it was found that the time in this steaming mode changes depending on the total amount of heat of the object to be heated. Table 2 shows the experimental results for manual heating.

(Margin below) Figure 4 is a time chart showing that the steaming time depends on the total amount of heat of the object to be heated.

As is clear from these, even if the object to be heated is the same, if the set time is extended, the steaming time will be extended. It can also be seen that the steaming time is the heating time obtained by adding the detection time and setting time, which differ depending on the type of the object to be heated, that is, the total amount of heat and the steaming time tend to extend in the same way.

Therefore, in the case of manual heating, the steaming time can be automatically calculated based on the gas sensor detection time (T) and the set time from the set heating mode time.

That is, the steaming time T is determined by the following formula.

T=3(T++A,)+D K3; Coefficient D=constant, which varies depending on the type of heated object
A: The steaming time to return to normal pressure can be automatically ended by arithmetic processing that takes the timer setting time.

Next, the operation of the fan will be explained. During the first half of steaming, the internal pressure of the container is still high enough that heating continues even if the heating means is stopped. During this time, it is preferable to stop the fan or reduce the air volume in order to utilize energy effectively. In the latter half of steaming, the temperature inside the container has already dropped and heating no longer progresses, so active cooling can actually shorten the steaming time.

FIG. 5 is a flowchart showing the operation of this control section.

When heating starts, it is first determined whether it is automatic heating or manual heating (al.

In the case of manual heating, a check is made to see if a predetermined amount of steam has been detected by the gas sensor (bl, and if it has reached point P, the heating time set on the timer is decreased (C1° and heating Once the time has elapsed (d), the heating is stopped.
el, shift to steaming mode.

The counted detection time (T2) and set time are multiplied by a predetermined coefficient K to calculate the steaming time (j'
).

And this will be gradually reduced.

If 3(TI+A)+D elapses during this steaming time, i
n+, steaming is stopped and finished. I will be
g+.

When the point P is finally reached, the heating time is calculated by multiplying the counted T1 by a predetermined coefficient K corresponding to the selected auto key (hl. Then, this is gradually decreased <(
i).

After this heating time K T + + B has elapsed, fj),
Heating is stopped (k) and the mode shifts to steaming mode.

The detection time (T2) is multiplied by a predetermined K according to the selected auto key to calculate the steaming time (p)
, and this is gradually decreased <(q).

If 2T20C elapses during this steaming time, the frl steaming will stop and end +S+.

Effects of the Invention As is clear from the above explanation, the pressure heating device of the first problem solving means uses a gas sensor to detect excess steam or gas released from the pressure regulating means, thereby controlling the It is possible to calculate steaming times that correspond to different objects to be heated and freely set heating times, and it is possible to perform semi-automatic operation.

Moreover, in the pressure heating device of the second problem solving means,
The gas sensor accurately detects the point at which the pressure regulating means starts operating, counts the time required until then, and
Based on this, the time from heating to steaming can be automatically determined.

As described above, the pressure heating device according to the present invention has the advantage that the predetermined time for the steaming mode can be automatically calculated and can be handled safely.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a pressure heating device according to an embodiment of the present invention, and FIG. 2 fa1. fb) is a front view of the main unit and an explanatory diagram of the pressure display pin operation, Fig. 3 is a time chart showing changes in steam and internal pressure, fat is a line diagram showing changes in steam detected by the gas sensor, (b) ) is a diagram showing the movement of the internal pressure of the pressure vessel at this time, (C1 is the fan operation diagram, Figure 4 fat, (bl is the change in steaming time due to the difference in manual heating setting time, and the internal pressure of the pressure vessel is 5 is a flowchart showing the operation of the control unit. 3...Time knob, 4...Auto key 5...Pressure adjustment means , 7... Pressure vessel, 11... Control unit, 13... Gas sensor. Name of agent: Patent attorney Shigetaka Awano )

Claims (2)

[Claims] (1) A pressure vessel that accommodates and seals an object to be heated, a pressure adjustment means provided in a part of the pressure vessel, a heating means that heats the pressure vessel, and a control unit that controls power supply to the heating means. and a timer means for setting the time for supplying power to the heating means, and a gas sensor for detecting excess steam or gas released from the pressure regulating means, and the control section controls the supply of power to the heating means. At the same time, the gas sensor detects the point in time when excess steam or gas starts to be released from the pressure regulating means or a certain point thereafter, and from that point on, the timer means is activated, and the time required for detection is counted. The pressure heating device is configured such that the control section stops power supply for a predetermined period of time. (2) A pressure vessel that accommodates and seals an object to be heated, a pressure adjustment means provided in a part of the pressure vessel, a heating means that heats the pressure vessel, and a control unit that controls power supply to the heating means. and a gas sensor that detects surplus steam or gas released from the pressure adjustment means, and the control unit starts supplying power to the heating means, and the control unit controls the pressure adjustment using the gas sensor. Detecting the point in time when surplus steam or gas begins to be released from the means or a certain point thereafter, counting the time required up to that point, and based on this, the control section continues supplying power to the heating means. A pressure heating device configured to shut down.