JPS5934311Y2 - Continuous pressurized microwave heating device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a microwave heating device that continuously heats an object to be heated, such as food or medicine, sealed and packaged in a container under high pressure.

BACKGROUND ART It has been common practice to heat-treat the contents sealed in a container, and for example, sterilization of foods or medicines using hot steam is well known.

However, the heating means described above is called an external heating method, and since heat is supplied from outside the container, it takes a long time to raise the center temperature of the object to be heated, which has the disadvantage of deteriorating quality. Food sealed in plastic containers had to be soaked in hot water at 120°C for nearly an hour.

Therefore, heat treatment methods using microwaves have recently come into use, but heating with microwaves is called an internal heating method, and due to rapid heating, the time required for heating is significantly reduced, which is extremely useful for shortening the process. be advantageous to

However, because the temperature of the contents rises rapidly, the saturated vapor pressure inside the container suddenly increases, which tends to cause damage to the container.

In this case, bag breakage can be prevented by applying higher pressure from the outside of the sealed container.

Apparatuses for heating and sterilizing foods sealed in packages using microwaves are disclosed in Japanese Patent Application Laid-open No. 53-119183 and Japanese Patent Publication No. 51-12133.

However, the apparatus disclosed in Japanese Patent Application Laid-Open No. 53-119183 is of a batch type and does not have good working efficiency.

Also, efficiency can be relatively improved if a large amount of packaged food is processed at one time, but if the packaged food is packed tightly together as in the retort method, the microwaves are easily absorbed by the food, so even the food placed in the center can be A phenomenon occurs where microwaves cannot reach the food and it cannot be heated.

Therefore, in order to apply microwaves uniformly, it is necessary to open a considerable passage for the microwaves, resulting in low processing capacity and a tendency to cause uneven heating.

In addition, microwaves are internal heating, and the food is heated rapidly, but packaging containers are usually made of materials that do not absorb microwaves, so the container cannot be heated, and the air inside the pot cannot be heated, so the container cannot be heated. The heat dissipated from the core is large, and it takes extra energy and time for the center to reach the desired temperature.

In addition, although the device disclosed in Japanese Patent Publication No. 51-12133 is a continuous type, the heating chamber and cooling chamber are not completely isolated, and the cooling water is heated by the microwaves leaking through the holes, resulting in poor cooling efficiency and overtack. Prone.

The above method uses rotary pulp, but the packaging is placed in the storage recess of a rotating body passed horizontally, and the packaging is taken out from the recess by gravity as the rotating body rotates, so the packaging is dropped onto the conveyor. There are pinholes in the body,
In many cases, the food inside collapsed and lost its commercial value.

The present invention has been made in view of the above points, and its purpose is to continuously process an object to be heated without leaking microwave-pressurized air.

In order to achieve this goal, the present proposal includes an inlet chamber with a belt conveyor for carrying in sealed containers for human wave heating, and a belt conveyor to receive and transfer the heated articles from the inlet chamber, and microwave irradiation. A microwave irradiation chamber equipped with a device, a steam introduction pipe, and a sheath heater; a cooling chamber equipped with a belt conveyor that receives the heated object from the microwave irradiation chamber and passes through a water tank; Continuous pressurization type, equipped with a belt conveyor for receiving items, a drying chamber equipped with a drying heater, pressurized air introduction pipes installed in these concave chambers, and each chamber can be opened and closed with a shutter. A microwave heating device was stolen.

An embodiment of the present invention will be described below with reference to FIG.

The pressurized continuous microwave heating device 10 of the present invention has a sealed container 11. Microwave irradiation chamber 12, cooling chamber 1
3, and the unloading room 14, which is a drying room, each has a shutter 1.
6, 17, and 18, and the loading port 11a of the loading chamber 11 and the loading port 14a of the loading chamber 14 can be opened and closed by shutters 15.19, respectively.

Each of the second concave chambers has a pressurizing pipe, that is, a pressurized air introduction pipe 2.
Although not shown in the drawings, a continuous belt conveyor 21 is installed therein, communicating with the near compressor.

A sheath heater 24a is provided in the loading chamber 11,
It heats the room and preheats the object to be heated, especially the container.

A steam inlet 22 is provided on the top plate 12a of the microwave irradiation chamber 12.
, a star fan 23, a sheath heater 24b1, an infrared thermometer 25, and a microwave oscillator 27 via a waveguide 26.
The flange 26a of the waveguide 26 is made of a material that allows microwaves to pass through but does not allow air to pass through, such as Teflon.

Infrared thermometer 25 is electrically connected to microwave oscillator 27 via controller 28 .

A water tank 29 is installed inside the cooling chamber 13, and belt conveyors 21c, 21d, and 21e are installed in the cooling water 30.

A sheath heater 24C is provided as a drying device in the unloading chamber 14, and the cooling water adhering to the container is dried.

An additional fan (not shown) may be provided to facilitate drying.

Further, the shutters 15, 16, 17, 18, and 19 are opened and closed by the vertical movement of a pressing plate 33 connected to a rod 32 by an air cylinder 31, and the lower edge of the sealing plate 34 is connected to the machine frame. After contacting the upper edge of the press plate 35, the press plate 33 further descends a little, so that the lever 36 acts to press the seal plate 34 against the opening 37 of the machine frame 38, and the pressure seal 39 shown in FIG. The microwave seal 40 completely prevents leakage of both.

Now, the process of performing heat treatment using the apparatus of the present invention which has been stolen as described above is as follows.

First, the artificial shutter 15 of the loading chamber 11 is opened, and after carrying in the object to be heated A, the shutter 15 is closed, the object to be heated A is preheated by the sheath heater 24a, and the compressed air introduced by the compressor through the pressure pipe 20 is The shutter 16 is opened when the pressure reaches the same level as the microwave irradiation chamber 12, which is kept at a high pressure in advance to prevent damage to the container during heating of the heated object. The object is transferred to the microwave irradiation chamber 12.

After closing the shutter 16 and isolating the loading chamber 11 and the microwave irradiation chamber 12, the microwave oscillator 27 is connected to the waveguide 26.
radiating microwaves to heat objects through
However, by stirring the microwaves using the stirrer fan 23 and making the radiation uniform, uneven heating of the object to be heated is eliminated.

Furthermore, if the heat dissipation from the surface of the sealed container is large depending on the material of the sealed container and it takes a long time for the object to be heated to reach a predetermined temperature, steam may be introduced from the inlet 22 and the sheath heater 24b may be used. By doing so, it is possible to prevent heat radiation from the surface of the container, heat the container from the outside, and shorten the heating time using microwaves accordingly.

For example, in the case of retort food, the sterilization effect can be obtained by heating it at 120°C for 4 minutes or more.
By controlling the oscillator 27, the temperature of the heated object can be kept constant.

After irradiating microwaves for a certain period of time as described above, the shutter 17 of the cooling chamber 13 is opened, and the object to be heated A passes through the water tank 30 by the conveyors 21c, 21d, and 21e and is cooled. The chamber 13 is maintained at the same pressure as the microwave irradiation chamber 12 by compressed air from a pressurizing pipe 20 installed on its top plate, so that the air pressure transferred from the microwave irradiation chamber 12 is The container containing the heated material will not be damaged by its internal pressure.

Next, the object to be heated A, which has been cooled here so that there is no risk of damage or deformation of the container, is transferred to the unloading chamber 14 by opening the shutter 18, where it is dried by heat dissipation from the sheath heater 24c, and then the shutter 19 is opened. and transported out of the equipment.

As explained above, the pressurized continuous microwave heating device of the present invention prevents heat dissipation by steam without being affected by the material of the container for the heated object, and constantly and reliably heats the heated object in a short time in each chamber. By alternately opening and closing, heat treatment can be performed continuously, and since the cooling water is completely isolated from microwaves, cooling efficiency is high, and the heated object will not be overtucked. Moreover, this conveying device does not apply any impact to the containers, so it has the characteristic that no pinholes are created in the containers.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the device of the present invention, and FIG. 2 is an enlarged sectional view of the opening wall. 10...Pressure continuous microwave heating device of the present invention, 11... Loading chamber, 12... Microwave irradiation chamber, 13... Cooling chamber, 14...
Carrying out room, 15.16.17.18.19... Shutter, 20... Pressurizing pipe, 21...
... Belt conveyor, 22 ... Steam inlet,
23... Stara fan, 24... Sheath heater, 25... Infrared thermometer, 26...
... Waveguide, 27 ... Microwave oscillator, 2
8... Controller, 29... Water tank, 30... Cooling water, 31... Air cylinder, 32... Rod, 33... ... Pressing plate, 34 ... Sealing plate, 35 ... Machine frame, 36 ... Lever, 37 ... Opening wall,
38...Machine frame, 39...Pressure seal 40...Microwave seal.

Claims (1)

[Scope of utility model registration request] A sealed container is equipped with a loading chamber equipped with a belt conveyor for carrying in human-wave heated materials, a belt conveyor that receives and connects the heated materials from the loading chamber, and equipped with a microwave irradiation device, a steam introduction pipe, and a sheath heater. A cooling chamber is equipped with a belt conveyor that passes through a water tank to receive and transfer objects to be heated from the microwave irradiation chamber, and a belt conveyor that receives and transfers objects to be heated from the cooling chamber. and a drying chamber equipped with a drying heater, pressurized air introduction pipes are provided in these concave chambers, and each chamber can be opened and closed with a shutter.