JP3391350B2 - Vacuum cooling device temperature measurement device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature measuring device for a vacuum cooling device.

[0002]

2. Description of the Related Art As is well known, a vacuum cooling device vacuum-sucks and decompresses the inside of a cooling tank in which a substance to be cooled is contained, thereby lowering the saturated vapor temperature and evaporating the water content of the substance to be cooled. By using the latent heat of vaporization at that time, the object to be cooled is cooled. This vacuum cooling device is used, for example, in the food industry in the process of packaging and shipping cooked food in a container.

In this vacuum cooling device, a temperature sensor is inserted into the object to be cooled, the cooling state of the object to be cooled can be confirmed based on the detection signal from the temperature sensor, and the operation of the vacuum suction means can be controlled. Has been done.

The insertion of the temperature sensor is a very complicated work since the operator manually inserts it into the object to be cooled, and sometimes the operator forgets to insert it. Also,
The difference in the insertion depth causes a difference in the measured temperature.

[0005]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to indirectly measure the temperature of an object to be cooled, eliminate the need for inserting a temperature sensor, and stabilize the temperature of the object to be cooled. And to measure automatically.

[0006]

The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is provided with a cooling tank for accommodating an object to be cooled, and this cooling tank is provided with outside air. It is characterized in that an introduction line is connected, a water tank is provided in this outside air introduction line, and a temperature detecting means is provided in this water tank.

Further, the invention according to claim 2 is provided with a cooling tank for accommodating an object to be cooled, a water tank is provided in communication with the cooling tank, and temperature detecting means is provided in the water tank. Install a heat exchanger in the vacuum suction line connected to
The outlet side of the heat exchanger in the cooling water distribution line provided in the heat exchanger and the water tank are connected by a makeup water supply line.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described. The vacuum cooling device according to the present invention is provided with a cooling tank having a sealable door, and the object to be cooled is accommodated in the cooling tank. A vacuum suction line and an outside air introduction line are connected to the cooling tank, a heat exchanger and a vacuum suction means are provided at the vacuum suction line, and an outside air introduction means is provided at the outside air introduction line. The heat exchanger serves to circulate cooling water to cool and condense the steam in the exhaust gas and reduce the volume of the discharged gas. A vacuum pump, a steam ejector, a water ejector or the like is used as the vacuum suction means. Of these vacuum suction means, a plurality of types may be used in combination. An electromagnetic valve, a motor valve, or the like is used as the outside air introducing unit.

A water tank having a relatively small capacity is provided in communication with the cooling tank. This water tank is installed in the cooling tank, the outside air introduction line or the vacuum suction line. Further, the water tank is provided with a temperature detecting means. The amount of water in the water tank is set in consideration of the size, temperature and specific heat (that is, heat capacity) of the object to be cooled. When the pressure in the cooling tank is reduced, the water in the water tank evaporates from the water surface of the water tank and the surface of the water absorbing member, and the temperature of the water in the water tank decreases in the same manner as the object to be cooled. Therefore, the temperature detection means can indirectly measure the temperature of the object to be cooled.

Here, the water tank is preferably installed in the outside air introduction line. By doing so, clean air is always in contact with the water in the water tank, and the slag of the object to be cooled scattered in the cooling tank does not enter the water tank, which is very hygienic. is there.

Further, the water in the water tank is replaced every vacuum cooling operation. Further, in order to improve the accuracy of temperature measurement, the temperature of the water in the water tank is warmed to the same level as the initial temperature of the object to be cooled. As this heating means, an electric heater or the like is provided, but the outlet side of the heat exchanger in the cooling water distribution line provided in the heat exchanger and the water tank are connected by a makeup water supply line, The water heated by the exchanger is supplied to the water tank. According to this configuration, the amount of heat for heating the water in the water tank can be saved, which is economical.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. The vacuum cooling device according to the present invention includes a cooling tank 2 that accommodates the object to be cooled 1. The cooling tank 2 has a door (not shown) and has a structure capable of being hermetically sealed. A plurality of shelves 3 are detachably provided in the cooling tank 2, and the objects to be cooled 1 are placed on the shelves 3. A vacuum suction line 4 and an outside air introduction line 5 are connected to the cooling tank 2.

In the vacuum suction line 4, the cooling tank 2 is provided.
Heat exchanger 6, check valve 7 and vacuum pump 8 in order from the side
Is provided. The heat exchanger 6 has a function of circulating cooling water to cool and condense steam in exhaust gas and reduce the volume of gas to be discharged. The check valve 7 functions to maintain a depressurized state in the cooling tank 1. The vacuum pump 8 is a water-sealed type in the illustrated embodiment,
The sealing water is supplied to form a liquid ring inside, and the gas is sucked and discharged by the rotation of the liquid ring.

The outside air introduction line 5 has a filter 9, an outside air introduction valve 10 and a water tank 1 in this order from the outside air introduction side.
1 is provided. The filter 9 removes dust, bacteria, etc. in the outside air introduced into the cooling tank 2. The outside air introduction valve 10 adjusts the speed of re-compression by adjusting the flow rate of air flowing into the cooling tank 2 through the outside air introduction line 5. In order to indirectly measure the temperature of the object to be cooled 1, the water tank 10 collects water whose temperature and amount are set so as to have a heat capacity approximately equal to the heat capacity of one object to be cooled 1. There is.

The water tank 11 has a temperature detecting means 12
Is provided. The temperature detecting means 12 uses a wet bulb temperature sensor 13 in the first embodiment, and a water absorbing member 14 having water absorbing property is provided from the temperature sensing portion (reference numeral omitted) to below the water surface of the water tank 11. It is arranged. As the water absorbing member 14, a fibrous material such as cloth or a porous material such as sponge is used. Due to the action of the water absorbing member 14, both water and water vapor come into contact with the temperature sensing part, and the surroundings of the temperature sensing part are filled with saturated water vapor. Therefore, the wet bulb temperature sensor 13 detects the water temperature (= steam temperature), and the pressure calculation means 15 calculates the pressure from the relationship between the saturation temperature and the saturated vapor pressure stored in advance based on the detected temperature. To do.
These temperatures and pressures are displayed by an appropriate display means.

The heat exchanger 6 includes a cooling water distribution line 1
6 is provided, and heat exchange is performed between the cooling water flowing through the cooling water distribution line 16 and the suction gas from the cooling tank 2. As a result, the suction gas is cooled, while the water flowing through the cooling water distribution line 16 is heated. An outlet side of the heat exchanger 6 in the cooling water distribution line 16 and the water tank 11 are connected by a makeup water supply line 17, and a part of the water heated by the heat exchanger 6 is connected to the water tank. I am going to supply to 11. This makeup water supply line 17 is provided with a makeup water solenoid valve 18, and this makeup water solenoid valve 1
The supply of makeup water is controlled by 8. The water tank 11 is provided with heating means such as an electric heater (not shown), and the temperature of the water supplied to the water tank 11 via the makeup water supply line 17 is lower than the initial temperature of the object to be cooled 1. If this is the case, heat to a value close to this. The heating means may be provided in the makeup water supply line 17.

The water tank 11 has a discharge solenoid valve 19
Is connected to the discharge line 20. The water in the water tank 11 is automatically replaced every vacuum cooling operation. The vacuum pump 8 and the outside air introduction valve 1
0, the make-up water solenoid valve 18 and the discharge solenoid valve 1
9 is controlled by the controller 21 according to a preset program. The pressure calculation means 15 is provided in the controller 21. An inlet side of the heat exchanger 6 in the cooling water distribution line 16 and the vacuum pump 8 are connected by a sealed water supply line 22.

Next, the operation of the above configuration will be described. After the object to be cooled 1 is housed in the cooling tank 2 and the door (not shown) is closed, the operation switch is turned on and the vacuum cooling process is started. The discharge solenoid valve 19 is opened to discharge the water in the water tank 11, and the discharge solenoid valve 1
After closing 9, the make-up water solenoid valve 18 is opened to supply make-up water. After supplying a predetermined amount of makeup water, the solenoid valve 18 for makeup water is closed. When the temperature of water is lower than the initial temperature of the object to be cooled 1, it is heated by the heating means (not shown). Then, the vacuum pump 8 is operated to reduce the pressure in the cooling tank 2. At the same time, cooling water is supplied to the heat exchanger 6 through the cooling water distribution line 16.

During depressurization, the wet-bulb temperature sensor 13 indirectly measures the temperature of the object to be cooled 1 to monitor whether or not the vacuum cooling is performed according to the program. Water evaporates from the water surface of the water tank 11 and the surface of the water absorbing member 14, and the temperature of the water in the water tank 11 drops in the same manner as the object to be cooled 1. Further, the pressure in the cooling tank 2 is calculated based on the temperature detected by the temperature detecting means 12. When it is detected that the pressure in the cooling tank 2 has dropped to a predetermined value, the vacuum pump 8 is stopped.
Then, the outside air introduction valve 10 is operated to operate the cooling tank 2
Clean outside air is introduced into the inside of the cooling tank 2 to restore its pressure. After the pressure in the cooling tank 2 returns to atmospheric pressure, the door is opened and the object to be cooled 1 is taken out.

FIG. 2 shows a second embodiment of the present invention. The same members as those of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In the second embodiment, as the temperature detecting means 12, a normal temperature sensor 23 is provided instead of the wet bulb temperature sensor 13.
Then, the temperature sensitive portion of the temperature sensor 23 is directly immersed in the water tank 11. From the viewpoint of accuracy of temperature measurement, it is better to use the wet bulb temperature sensor 13 in the first embodiment, but also in the configuration of the second embodiment, the actual temperature of the object to be cooled 1 and the temperature sensor. It can be carried out if the difference from the temperature detected by 23 is confirmed in advance by an experiment.

[0021]

According to the present invention, the temperature of the object to be cooled can be indirectly measured, and the temperature of the object to be cooled can be stably and automatically measured. Therefore, it is not necessary to insert the temperature sensor as in the conventional case, and the measured temperature does not vary due to a defective insertion of the temperature sensor. If a water tank is installed in the outside air introduction line,
The clean air is always in contact with the water in the water tank, and the debris of the object to be cooled scattered in the cooling tank is not mixed in the water tank, which is very hygienic. Furthermore, the configuration in which a part of the water on the outlet side of the heat exchanger of the cooling water distribution line is supplied to the water tank can save the amount of heat for heating the water in the water tank, which is very economical. .

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a second embodiment of the present invention.

[Explanation of symbols]

1 Cooled object 2 cooling tanks 4 vacuum suction line 5 Outside air introduction line 6 heat exchanger 11 water tank 12 Wet bulb temperature sensor 16 Cooling water distribution line 17 Make-up water supply line

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoya Tateishi 7 Horie-cho, Matsuyama-shi, Ehime Prefecture Miura Industrial Co., Ltd. (56) Reference JP-A-6-313660 (JP, A) JP-A-10- 19684 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F25D 7/00

Claims (2)

(57) [Claims] 1. A cooling tank 2 for accommodating an object to be cooled 1,
An outside air introducing line 5 is connected to the cooling tank 2, a water tank 11 is provided in the outside air introducing line 5, and a temperature detecting means 12 is provided in the water tank 11, which is a temperature measuring device of a vacuum cooling device. 2. A cooling tank 2 for accommodating an object to be cooled 1,
A water tank 11 is provided in communication with the cooling tank 2, a temperature detecting means 12 is provided in the water tank 11, a heat exchanger 6 is provided in a vacuum suction line 4 connected to the cooling tank 2, and the heat exchanger 6 is provided. A temperature measuring device for a vacuum cooling device, characterized in that an outlet side of the heat exchanger 6 in the cooling water distribution line 16 provided in the above is connected to the water tank 11 by a makeup water supply line 17.