JP7550096B2 - Temperature measuring device and heat treatment device - Google Patents

Description

The present invention relates to a temperature measuring device that measures the atmospheric temperature inside a treatment tank in which an object to be treated is cooled under reduced pressure, and a heat treatment device equipped with this temperature measuring device.

When heat sterilizing food, etc., it is common to heat it with steam and then vacuum cool it. A processing device that performs this type of processing includes a processing tank, a heating mechanism that allows high-temperature steam to flow into the processing tank, and a decompression mechanism that reduces the pressure inside the processing tank. In this processing device, food is placed in the processing tank, vacuum degassed, and then high-temperature steam is allowed to flow into the processing tank, thereby heat sterilizing the food. Furthermore, when the processing tank is decompressed after heat sterilization of the food, the boiling point of the liquid in the processing tank is lowered, causing moisture to evaporate from the surface and inside of the food. The food is cooled by the heat of vaporization generated when this moisture evaporates.

In this heat sterilization and vacuum cooling, for example, a temperature sensor is placed in the treatment tank to measure the atmospheric temperature inside the treatment tank. However, during vacuum cooling, the pressure inside the treatment tank is reduced, which causes steam and air to be exhausted from inside the treatment tank, reducing the amount of medium for detecting temperature around the temperature sensor, which causes the temperature sensor to be unable to accurately measure the atmospheric temperature.

To address this problem, a temperature measuring device has been proposed that includes a container that is placed in a treatment tank and contains water, and a temperature sensor that is placed close to the water surface in the container (see Patent Document 1). In this temperature measuring device, water vapor is generated near the water surface in the container. Therefore, when the temperature sensor comes into contact with the generated water vapor, the temperature of the temperature sensor follows the change in the atmospheric temperature in the treatment tank. This allows the temperature sensor to accurately measure the atmospheric temperature in the treatment tank.

Patent No. 4810324

However, with the temperature measuring device, the pressure inside the treatment tank decreases during vacuum cooling, causing the water inside the container to evaporate, which in turn causes the water inside the container to cool, making evaporation less likely and resulting in extremely little water vapor near the water surface inside the container. This can sometimes prevent the temperature sensor from measuring the ambient temperature inside the treatment tank.

The present invention aims to provide a temperature measuring device that can more accurately measure the atmospheric temperature inside a treatment tank even when the treatment tank is placed in a vacuum state to cool the object to be treated, and a heat treatment apparatus equipped with this temperature measuring device.

The temperature measuring device of the present invention is disposed in a treatment tank that cools the object to be treated under reduced pressure, and measures the temperature in the treatment tank under reduced pressure. The device includes a container that contains water, a temperature sensor that is provided above the water surface in the container, and a fluid supply unit that supplies a fluid that promotes evaporation of the water in the container.

With this configuration, the water in the container continues to boil due to the fluid supply from the fluid supply unit that promotes the evaporation of water, so the temperature sensor is in continuous contact with the steam evaporating from within the container and follows the changes in the ambient temperature in the treatment tank, enabling more accurate temperature measurement.

In the temperature measuring device, the fluid that promotes evaporation of the water in the container may be steam.

With this configuration, the fluid supply unit continues to boil the water in the container using the heat of the steam, while at the same time supplying water produced by condensation of the steam into the container, making it difficult for the water in the container to run out.

The temperature measuring device is placed in a treatment tank together with the object to be treated, and measures the temperature in the treatment tank when the object to be treated is cooled under reduced pressure. The temperature measuring device may include a temperature sensor and a fluid supply unit that supplies steam near the temperature sensor.

With this configuration, the temperature sensor comes into contact with the steam supplied from the fluid supply unit and follows the changes in the ambient temperature inside the treatment tank, enabling more accurate temperature measurement.

The heat treatment device of the present invention includes the temperature measuring device, the treatment tank, and a steam generating device that generates heated steam for heating the object to be treated in the treatment tank, and the fluid supply unit is connected to the steam generating device and supplies the heated steam generated by the steam generating device.

With this configuration, heat and water can be supplied to the container using a steam generator that supplies steam for thermal sterilization.

As described above, according to the present invention, it is possible to provide a temperature measuring device that can more accurately measure the atmospheric temperature inside a treatment tank even when the treatment tank is placed in a vacuum state to cool the object to be treated, and a heat treatment apparatus equipped with this temperature measuring device.

FIG. 1 is a schematic diagram of a heat treatment apparatus according to the present embodiment. FIG. 2 is an enlarged cross-sectional view of the periphery of a temperature measuring device of the heat treatment device. FIG. 3 is an enlarged cross-sectional view of the periphery of a temperature measuring device of a heat treatment apparatus according to another embodiment.

The first embodiment of the present invention will be described below with reference to Figs. 1 and 2. As shown in Fig. 1, the temperature measuring device 1 according to this embodiment is disposed in a processing tank 6 in which the object to be processed 7 is cooled under reduced pressure, and measures the temperature inside the processing tank 6 under reduced pressure. The temperature measuring device 1 is installed, for example, in a heat treatment device 10. Specifically, the temperature measuring device 1 is used when the degassing process, the steam sterilization process following the degassing process, and the vacuum cooling process are performed by a short-time cooking sterilization device RIC manufactured by Hisaka Works Ltd. Furthermore, the temperature measuring device 1 measures the temperature inside the processing tank 6 during these processes.

The heat treatment device 10 includes a temperature measuring device 1, a treatment tank 6, and a steam generator 8 that generates heated steam for heating the treatment object 7 in the treatment tank 6.

The treatment tank 6 can accommodate, for example, one temperature measuring device 1 and multiple objects to be treated 7. In this embodiment, the treatment tank 6 constitutes a heat treatment device 10 together with a steam generating device 8 and a pressure reducing device that degass the treatment tank 6 to create a vacuum state.

The object to be treated 7 is, for example, food such as cooked rice and a packing container that contains the food. The packing container is, for example, a container made of resin.

As shown in FIG. 2, the temperature measuring device 1 includes a container 3 that contains water 2, a temperature sensor 4 that is provided above the water surface 20 in the container 3, and a fluid supply unit 5 that supplies a fluid that promotes evaporation of the water 2 in the container 3. In this embodiment, the temperature measuring device 1 is placed on a bracket 60 that is attached to the inner wall of the treatment tank 6.

For example, the container 3 is a metal container or a resin container. In this embodiment, the container 3 is a stainless steel container. The container 3 has an open top and is, for example, a cylindrical shape with a bottom. The height of the water in the container 3 is, for example, 20 mm to 40 mm.

The container 3 may be provided with a lid that covers the open part of the container 3 (the open part provided at the top). A plate-shaped cover or the like may be provided between the container 3 and the object to be treated 7. This makes it possible to prevent the water 2 from splashing on the object to be treated 7 even if the water 2 in the container 3 bumps due to the fluid supply from the fluid supply unit 5 or the like.

The temperature sensor 4 is a sensor that can measure the temperature of the atmosphere in which the temperature sensor 4 is placed by contacting a medium such as water vapor or air. In this embodiment, the temperature sensor 4 is a thermocouple, a thermistor, a resistance temperature detector, or the like. The temperature sensor 4 is placed, for example, 5 mm to 15 mm above the water surface 20.

The fluid supply unit 5 is, for example, a member that supplies a fluid that promotes evaporation of the water 2 in the container 3 into the water 2 contained in the container 3. The fluid that promotes evaporation of the water in the container is a fluid with a higher temperature than the temperature in the treatment tank 6, and is preferably a high-temperature fluid that contains water. In this embodiment, the fluid that promotes evaporation of the water in the container is steam.

Specifically, the fluid supply unit 5 is connected to the steam generator 8 and supplies heated steam generated by the steam generator 8. More specifically, the fluid supply unit 5 may be a sub-pipe that branches off from the main pipe of the steam generator 8. In this case, the fluid supply unit 5 can supply heated steam to the water 2 in the container 3 even when the valve of the main pipe is closed.

The fluid supply unit 5 continuously supplies steam during the process of cooling the treatment object 7 under reduced pressure. The amount of steam supplied by the fluid supply unit 5 is changed according to a preset value (e.g., the ratio of the supply amount to the maximum supply amount of steam). The amount of steam supplied by the fluid supply unit 5 may be changed appropriately according to the air pressure in the treatment tank 6 instead of a preset value. The amount of steam supplied is adjusted, for example, by changing the opening of a valve (specifically, an automatic valve) provided in the sub-pipe.

According to the temperature measuring device 1 described above, the water 2 in the container 3 continues to boil due to the supply of fluid by the fluid supply unit 5 that promotes the evaporation of water, so the temperature sensor 4 is continuously in contact with the steam evaporating from the container 3, and the temperature of the temperature sensor 4 follows the change in the ambient temperature in the treatment tank 6. This allows the temperature sensor 4 to measure temperature more accurately.

In the temperature measuring device 1 of this embodiment, the fluid supply unit continues to boil the water in the container using the heat of the steam, and at the same time, water produced by condensation of the steam is supplied into the container, making it difficult for the water in the container to run out.

In addition, with this heat treatment device 10, heat and water can be supplied to the container 3 using a steam generator 8 that supplies steam for heat sterilization.

The temperature measuring device 1 may also include at least one of a porous material that is contained in the container 3 while immersed in the water 2 in the container 3 and is made of a porous material, and an agitator that agitates the water in the container 3. The porous material is, for example, boiling stones. The agitator is, for example, a magnetic stirrer. In this configuration, the porous material and the agitator can prevent the water 2 in the container 3 from bumping.

Next, a second embodiment will be described. As shown in FIG. 3, the temperature measuring device 1 according to the second embodiment includes a temperature sensor 4 and a fluid supply unit 5 that supplies steam near the temperature sensor 4. Therefore, the temperature sensor 4 comes into contact with the steam supplied from the fluid supply unit 5, and the temperature of the temperature sensor 4 follows the change in the ambient temperature in the treatment tank 6. This enables the temperature sensor 4 to perform accurate temperature measurement.

The temperature measuring device of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the configuration of one embodiment can be added to the configuration of another embodiment, and part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, part of the configuration of one embodiment can be deleted.

In the above embodiment, the processing target 7 was food, but it may also be medicine, etc.

1...Temperature measuring device, 2...Water, 3...Container, 4...Temperature sensor, 5...Fluid supply section, 6...Treatment tank, 7...Object to be treated, 8...Steam generating device, 10...Heat treatment device, 20...Water surface, 60...Bracket

Claims (4)

A temperature measuring device that is disposed in a treatment tank for cooling an object to be treated under reduced pressure and measures a temperature in the treatment tank under reduced pressure,
A container for containing water;
a temperature sensor provided above the water surface in the container;
A temperature measuring device comprising: a fluid supply unit that supplies a fluid that promotes evaporation of water in the container. The temperature measuring device according to claim 1, wherein the fluid that promotes evaporation of the water in the container is steam. A temperature measuring device that is placed in a treatment tank together with a treatment object and measures the temperature in the treatment tank when the treatment object is cooled under reduced pressure,
A temperature sensor;
A temperature measuring device comprising: a fluid supply unit that supplies steam to the vicinity of the temperature sensor. A temperature measuring device according to any one of claims 1 to 3,
The treatment tank;
a steam generator for generating heating steam for heating the object to be treated in the treatment tank;
The fluid supply unit is connected to the steam generator and supplies heated steam generated in the steam generator.