JPH04347418A - heating cooking device - 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]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating cooking apparatus that uses microwaves to perform cooking such as defrosting, stewing, and reheating, and particularly relates to a heating cooking apparatus that uses a pressure reducing means.

0002

2. Description of the Related Art As shown in FIG. 3, a conventional heating cooking device of this type includes a cooking chamber 1, a magnetron 2 that emits microwaves to the food in the cooking chamber 1, and a vacuum pump 14 to defrost the food. In addition to heating functions such as , simmering, and reheating, the cooking chamber 1 was also equipped with a function to reduce the pressure in the cooking chamber 1 to boil the water in the food, and use the heat of vaporization at that time to cool the food. (Special Publication No. 2-50368)

0003

However, in the above configuration, the required cooking temperature and cooking time vary depending on the cooking functions such as defrosting, stewing, and reheating, and the food to be cooked. For example, even with the reheat function, the heating temperature for rice is 80.
℃ (saturation pressure at this time is 355 mmHg), whereas if it is a protein-based product such as milk, it is necessary to lower the temperature to 60 degrees Celsius or less (saturation pressure at this time is 150 mmHg). Furthermore, in the case of thawing, it is necessary to lower the temperature even further. The cooking time is related to this cooking function. In order to satisfy all of these requirements, the decompression pump would have to be quite large, resulting in a large device.

The present invention solves the above problem by increasing the pumping speed of the vacuum pump for cooking functions and cooking products where the heating temperature is relatively high (that is, the pressure is high).
For cooking functions that shorten cooking time and require low heating temperatures (that is, low pressure), the exhaust speed of the pressure reducing pump is increased at the beginning of operation, and when the predetermined pressure is reached, the ultimate vacuum pressure of the pressure reducing pump is increased. The purpose of this is to switch to a lower condition to make it possible to improve the quality of cooked products, shorten cooking time, and downsize the equipment.

[0005]

[Means for Solving the Problems] In order to achieve the above objects, the present invention includes a cooking chamber that can be freely sealed, a heating means for heating the food in the cooking chamber, and a pressure detector for detecting the pressure inside the cooking chamber. a multi-stage pressure reduction pump that reduces the pressure in the cooking chamber; a first connection pipe that connects the cooking chamber and the first stage medium inlet of the pressure reduction pump; and an intermediate between the first connection pipe and the pressure reduction pump. a second connecting pipe connecting the medium inlet of the second stage, which has a higher pressure than the first stage; a four-way valve provided in the middle of the second connecting pipe; and one connecting pipe to the medium outlet of the first stage of the pressure reducing pump. A third connecting pipe having the other end connected to the four-way valve, and a fourth connecting pipe having a first on-off valve connected to the four-way valve are provided.

[0006]

[Function] With the above-mentioned structure, when it is desired to cook at a relatively high heating temperature (that is, at a high pressure), the present invention uses a four-way valve to direct the medium between the first connecting pipe and the second connecting pipe;
The third connecting pipe and the fourth connecting pipe are made to flow respectively, the first on-off valve is opened, and the pressure reducing pump is used in a single stage to increase the exhaust speed, thereby shortening the cooking time. On the other hand, if you want to cook at a low heating temperature (that is, low pressure), at the beginning of operation, the four-way valve allows the medium to flow between the first and second connecting pipes, and between the third and third connecting pipes. Flow through each of the four connecting pipes, and open the first on-off valve to increase the pumping speed of the pressure reducing pump to quickly lower the pressure to the predetermined pressure of the pressure sensor. Then, in response to a signal from the pressure sensor, the four-way valve causes the medium to flow through the first connecting pipe and the fourth connecting pipe, and the second connecting pipe and the third connecting pipe, respectively, and the first on-off valve is closed, and the vacuum pump is used in multiple stages to lower the vacuum pressure achieved and improve the quality of cooking.

[0007]

Embodiments An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In FIG. 1, 1 is a cooking chamber, 2 is a magnetron, 3 is an oven, and 4 is a vacuum pump, which are arranged in multiple stages. 5 is a pressure sensor, and 6 is a first connecting pipe, which connects the cooking chamber 1 and the medium inlet of the pressure reducing pump 4. Reference numeral 7 denotes a second connecting pipe, which connects the middle of the first connecting pipe 6 to the medium inlet of the second stage, which has a higher pressure than the first stage of the pressure reducing pump 4. 8 is a four-way valve, and the second connecting pipe 7
It is set in the middle. Reference numeral 9 denotes a third connecting pipe, one end of which is connected to the medium outlet of the first stage of the pressure reducing pump 4, and the other end thereof to the four-way valve 8. 10 is a fourth connecting pipe, which is connected to the four-way valve 8. The four-way valve 8 allows the medium to flow in the forward direction (direction of the solid line arrow in FIG. 1) through the first connecting pipe 6 and the second connecting pipe 7, and the third connecting pipe 9 and the fourth connecting pipe 10, respectively. , the first connecting pipe 6 and the fourth connecting pipe 10 and the second connecting pipe 7 and the third connecting pipe 9 are switched to flow in the opposite direction (in the direction of the dashed arrow in FIG. 1). Reference numeral 11 denotes a first on-off valve, which is provided in the four connecting pipes, and is opened when the four-way valve 8 is in the forward direction and closed when it is in the reverse direction.

[0009] In the above-mentioned configuration, first, we will describe the operation when it is desired to perform cooking at a high heating temperature (that is, with a high vacuum pressure), such as stewing or reheating. The food in the cooking chamber 1 of the oven 3 is heated by microwaves emitted from the magnetron 2, and its temperature rises. On the other hand, since the pressure inside the cooking chamber 1 is reduced by the pressure reducing pump 4, the pressure gradually decreases. When the saturation pressure of the temperature of the cooked product and the pressure inside the cooking chamber 1 begin to match, the water in the cooked product begins to boil at that temperature, and the cooking is completed. Therefore, since the temperature does not rise above a predetermined temperature, problems such as protein decomposition do not occur when, for example, protein-based cooking is performed. In this cooking, since the four-way valve 8 is switched in the forward direction, the medium flows from the cooking chamber 1 through the first connecting pipe and the second connecting pipe to the vacuum pump, as shown by the solid line in FIG. 4
flows into. Therefore, the decompression pump 4 operates in multiple stages, and the evacuation speed of the decompression pump is high. Therefore, the pressure within the cooking chamber 1 decreases quickly, and the cooking time can also be shortened. Next, we will discuss the effects when you want to cook at a low heating temperature (that is, low vacuum pressure), such as when defrosting. In this case, in the initial stage of operation, the operation continues in the same manner as when cooking is desired at a high heating temperature as described above, and the pressure in the cooking chamber 1 is rapidly lowered to a predetermined pressure. Then, the pressure sensor 5 acts to switch the four-way valve 8 in the opposite direction, and the medium flows from the first connecting pipe 6 to the first stage of the pressure reducing pump 4, as shown by the broken line in FIG. death,
Next, the medium flowing out from the first stage passes through the third connecting pipe 9, the four-way valve 8, and the second connecting pipe 7, and flows into the second stage of the pressure reducing pump 4. Therefore, since the medium is evacuated in multiple stages, the ultimate vacuum pressure can reach low conditions, and the thawing function can be thawed at a low temperature, improving quality and shortening cooking time, making the equipment more compact. It can also be measured. FIG. 2 shows the pumping speed characteristics of the decompression pump 4. In FIG. 2, the solid line shows the characteristics of the four-way valve 8 in the forward direction, and since the pressure reducing pump 4 operates in a single stage, the pumping speed is high, but the ultimate vacuum pressure is relatively high. On the other hand, the broken line in FIG. 2 shows the characteristics of the four-way valve 8 when facing the customer; in this case, the pressure reducing pump 4 is used in multiple stages, so the pumping speed is small but the vacuum output can be low. be.

0010

As explained above, the vacuum pump of the present invention includes a cooking chamber that can be freely sealed, a heating means for heating the food in the cooking chamber, and a pressure detector for detecting the pressure inside the cooking chamber. a multi-stage pressure reducing pump that reduces the pressure inside the cooking chamber;
a first connecting pipe connecting the cooking chamber and a first stage medium inlet of the pressure reducing pump; and a second stage medium inlet having a higher pressure than the first stage middle of the first connecting pipe and the first stage of the pressure reducing pump. a four-way valve provided in the middle of the second connecting pipe, and a third connecting pipe that connects one side to the medium outlet of the first stage of the pressure reducing pump and the other side to the four-way valve. and a fourth connecting pipe having a first opening/closing valve connected to the four-way valve, and for a cooking function where the heating temperature is relatively high (that is, the pressure is high) and the food to be cooked, the exhaust speed of the pressure reducing pump is high. Configure a four-way valve circuit to shorten cooking time. On the other hand, for cooking functions where the heating temperature is low (that is, the pressure is low), such as defrosting, a four-way valve circuit is configured to increase the pumping speed of the pressure reducing pump at the beginning of operation to quickly reduce the pressure in the cooking chamber. Then, when the pressure sensor detects that the pressure has dropped to a predetermined level, the four-way valve circuit is switched so that the vacuum pressure reached by the pressure reducing pump is lowered, and the vacuum pressure in the cooking chamber is lowered. This has the effect of improving quality and downsizing the equipment.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a cooking device according to an embodiment of the present invention.

FIG. 2 is a diagram showing the vacuum pump pumping speed characteristics of the cooking device in one embodiment of the present invention.

[Fig. 3] Schematic sectional view of a conventional heating cooking device

[Explanation of symbols]

1 Cooking room 2 Magnetron 4　Reducing pump 5 Pressure detector 6 First connecting pipe 7 Second connecting pipe 8 Four-way valve 9 Third connecting pipe 10 4th connecting pipe 11 First on-off valve

Claims (1)

[Claims] 1. A cooking chamber that can be closed, a heating means for heating food in the cooking chamber, a pressure detector for detecting the pressure inside the cooking chamber, and a multi-stage pressure reducing pump that reduces the pressure inside the cooking chamber. a first connecting pipe connecting the cooking chamber and a first stage medium inlet of the pressure reducing pump; and a second stage medium inlet having a higher pressure than the first stage middle of the first connecting pipe and the first stage of the pressure reducing pump. a four-way valve provided in the middle of the second connecting pipe, and a third connecting pipe that connects one side to the medium outlet of the first stage of the pressure reducing pump and the other side to the four-way valve. and a fourth connecting pipe having a first on-off valve connected to the four-way valve.