JP6467176B2 - Vacuum cooling device - Google Patents

Description

  The present invention relates to a vacuum cooling apparatus that cools an object to be cooled by using heat of vaporization generated when the inside of the treatment tank is depressurized and moisture is evaporated from the object to be cooled in the processing tank.

  There is a vacuum cooling device that accommodates an object to be cooled such as food cooked in a processing tank and cools the object to be cooled by reducing the pressure in the processing tank. When the inside of the treatment tank containing the object to be cooled is depressurized and the boiling point in the treatment tank is lowered below the temperature of the object to be cooled, moisture in the object to be cooled evaporates, and at that time, from the object to be cooled Since the heat of vaporization is taken away, the object to be cooled can be cooled in a short time. As a vacuum generator used for a vacuum cooling device, one using an ejector by water or steam or a water-sealed or dry vacuum pump is known. When the gas in the treatment tank is sucked by the vacuum generator, the vapor generated from the object to be cooled is sucked simultaneously with the sucked gas. However, since the volume of water greatly increases when water is changed to gas, if the vapor is sucked into the vacuum generator as it is, the amount of gas that must be discharged by the vacuum generator increases. In that case, since the time required for pressure reduction in the treatment tank becomes longer, the cooling process time becomes longer.

  Therefore, as described in Japanese Patent Laid-Open No. 7-139860, a heat exchanger (cold) that cools the gas sucked by the vacuum generator in the middle of a vacuum pipe that sends the gas in the processing tank to the vacuum generator. A trap is provided to cool the gas in the middle of the vacuum pipe. When the gas is cooled by the heat exchanger, the volume of the gas is reduced, and particularly when the vapor is cooled and returned to the liquid, the volume is significantly reduced. Cooling efficiency can be increased. In the invention described in Japanese Patent Laid-Open No. 7-139860, a cooling water circuit for flowing cooling water is inserted into the heat exchanger, and the cold water manufactured in the cold water unit and stored in the cold water tank is stored in the heat exchanger. By supplying to the cooling water circuit, the gas flowing around the cooling water circuit is cooled. Since the cold water tank which stores the cold water manufactured by the cold water unit is installed and the cold water in the cold water tank is supplied to the heat exchanger, the cold water can be stably supplied to the heat exchanger.

However, in the invention described in Japanese Patent Laid-Open No. 7-139860, the cooling water supplied to the heat exchanger is set to room temperature water in the initial stage of cooling, and then chilled water is supplied from a chilled water unit, so that The size is supposed to be reduced. In this case, there have been demerits such as an increase in cost due to complicated piping and an increase in water usage.

  In addition, in the vacuum cooling device described in Japanese Patent Application Laid-Open No. 2014-152982, a vacuum generator that is connected to the processing tank 2 that accommodates an object to be cooled, the processing tank 2 and the vacuum pipe 9 and sucks the gas in the processing tank. 1. The vacuum generator 1 has heat exchangers 4 and 5 for cooling the gas sucked from the treatment tank 2 in the middle, and a cold water unit 3 for producing cold water for use in the heat exchanger. In the vacuum cooling device that cools the object to be cooled by reducing the pressure, the heat exchanger has a configuration in which the heat exchanger tube of the heat exchanger is installed in the cold water tank 10 that collects the cold water produced by the cold water unit. The first heat exchanger 4 that penetrates the cold water portion from the upper part of the cold water tank to reach the lower part of the cold water tank, and the lower part of the cold water tank penetrates the cold water part to reach the upper part of the cold water tank. A second heat exchanger 5 are provided, the first heat exchanger and the second heat exchanger has a structure linked with a lower collection chamber provided in the lower portion of the cold water tank.

With such a configuration, since the heat exchanger and the cold water tank are integrated, a circulation path for circulating the cooling water between the cold water tank and the heat exchanger becomes unnecessary. By reducing the number of circulation pipes and the like, the space required for the apparatus can be reduced, and the apparatus cost can be reduced. In addition, if the heat exchanger and the cold water tank are provided separately, the containers required for each can be combined into one according to the present invention. It is possible to obtain an effect such that

However, in the vacuum cooling device configured as described above, if the condensed water generated by the suction gas being cooled by the first heat exchanger is accumulated in the lower collecting chamber as a drain, the drainage in the lower collecting chamber is caused by the progress of pressure reduction. Steam is generated from the water surface. Therefore, it is necessary to install a drain tank further below the lower collecting chamber so that the drain is discharged from the lower collecting chamber. In addition, the structure in which the drain tank is separately provided has caused an increase in the size of the apparatus, which has been a heavy burden in a small model.

JP 2014-152982 A

  The problem to be solved by the present invention is to save space and cost in a vacuum cooling device.

The invention according to claim 1 is a treatment tank for storing an object to be cooled, a vacuum generator connected to the treatment tank by a vacuum pipe and sucking a gas in the treatment tank, and the vacuum generator sucks from the treatment tank. In the vacuum cooling device that has a heat exchanger that cools the gas in the middle and cools the object to be cooled by reducing the pressure in the treatment tank, the heat exchanger has a first heat exchanger and a gas suction path. The second heat exchanger is provided in order, and the first heat exchanger and the second heat exchanger are connected through a common lower collecting chamber. The lower collecting chamber is provided with a shielding plate inside, and the lower collecting chamber is provided with a shielding plate. And the lower part of the lower collecting chamber is set as a drain reservoir, and the suction gas flowing from the first heat exchanger to the second heat exchanger passes through the upper part of the lower collecting chamber and passes through the first heat exchanger and the second heat exchanger. Drain generated in the heat exchanger goes to the drain reservoir below the shielding plate The shielding plate is provided with an opening for dropping the drain to the bottom of the lower collecting chamber on the side where the first heat exchanger is installed, and the second heat exchanger is installed. It is assumed that no opening is provided on the side, and the shielding plate is installed so as to be inclined so that the height decreases toward the opening.

According to a second aspect of the present invention, in the vacuum cooling apparatus, the shielding plate has a laterally extending surface connected to the side wall surface in the lower collecting chamber on the root side and a downwardly extending surface on the tip side. Yes, the surface extending downward from the front side of the shielding plate is installed at a position close to the side opposite to the side of the lower collecting chamber connecting the base side of the shielding plate. A space that occupies most of the lower part of the lower gathering chamber surrounded by the bottom surface is used as a drain reservoir, and most of the drain in the lower gathering chamber enters the drain reservoir.

According to a third aspect of the present invention, in the above vacuum cooling device, a drain outlet for sending drain into the drain reservoir, between the space in the upper part of the lower collecting chamber and the drain reservoir provided in the lower part, The air in the drain reservoir is communicated by an air vent for extracting the gas in the upper part of the lower collecting chamber, and the air vent is provided at a position higher than the drain outlet.

The lower collecting chamber provided at the lower part of the heat exchanger is divided into upper and lower parts by a shielding plate. The suction gas flowing from the first heat exchanger to the second heat exchanger flows in the upper part of the lower assembly chamber, and the drain generated in the first heat exchanger and the second heat exchanger is shielded by the influence of gravity. Flows down into the drain reservoir in the lower part of the lower assembly chamber. By separating the suction gas flow path and the drain water storage section in the lower assembly chamber, it is possible to prevent the drain from being sent to the second heat exchanger. In addition, the shielding plate installed in the lower collecting chamber closes the second heat exchanger installation side, and the opening for sending drain to the drain water storage unit is provided on the first heat exchanger installation side, so that the drain that has entered the drain water storage unit Can be more effectively prevented from being re-evaporated and sent to the second heat exchanger.

And if the front-end | tip of a shielding board is bent below, a drain water storage part can be divided clearly. If a drain outlet that sends drain to the drain reservoir is installed at a low position, the drain outlet will be blocked by drain when drain is accumulated in the drain reservoir, reducing the pressure in the lower collecting chamber. However, the pressure drop is moderate in the drain reservoir. In that case, evaporation from the drain reservoir can be reduced even if the pressure in the lower collecting chamber is reduced.

  By implementing the present invention, it is not necessary to install a drain tank separately from the lower collecting chamber at the lower part of the heat exchanger, and the apparatus can be reduced in size while preventing the drain from being sent to the second heat exchanger. The installation space can be reduced and the cost can be reduced.

Flow chart of vacuum cooling device in one embodiment of the present invention The partially transparent perspective view of the lower gathering chamber part in one Example of this invention Sectional drawing of the lower gathering chamber part in 2nd Example of this invention

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a flow chart of a vacuum cooling device in a first embodiment of the present invention, FIG. 2 is a partially transparent perspective view of a lower gathering chamber portion in one embodiment of the present invention, and FIG. 3 is a second embodiment of the present invention. It is sectional drawing of the lower gathering chamber part in an example. The vacuum cooling device includes a processing tank 2, a vacuum generator 1, a first heat exchanger 4, a second heat exchanger 5, a cold water unit 3, a cold water tank 10, and the like. The vacuum cooling device depressurizes the inside of the processing tank 2 to evaporate water from the object to be cooled accommodated in the processing tank 2, and performs cooling by the action of vaporization heat generated at that time.

  The processing tank 2 and the vacuum generator 1 are connected by a vacuum pipe 9 and the gas in the processing tank 2 is discharged by operating the vacuum generator 1. At this time, if the vapor generated from the object to be cooled is sucked by the vacuum generator 1 together with the gas in the treatment tank 2, the volume of the gas that the vacuum generator 1 must suck increases, and the treatment tank Since the pressure reduction in 2 takes time, the cooling time becomes longer. Therefore, the vacuum pipe 9 is provided with a heat exchanger, and by cooling the gas sucked by the vacuum generator 1 and the vapor contained in the gas, the volume of the gas to be sucked is reduced. ing.

  The heat exchanger has two systems of the upstream first heat exchanger 4 and the downstream second heat exchanger 5 and is provided in the cold water tank 10. The heat transfer tubes of the first heat exchanger 4 and the second heat exchanger 5 on the downstream side are installed so as to penetrate the water portion of the cold water tank 10. An upper dispersion chamber 11 for dispersing the gas sucked from the processing tank 2 to the plurality of heat transfer tubes of the first heat exchanger 4 and an upper part of the second heat exchanger 5 are disposed above the first heat exchanger 4. An upper collecting chamber 13 is provided for collecting the gases flowing through the plurality of heat transfer tubes of the second heat exchanger 5.

  The cold water tank 10 has a rectangular parallelepiped shape, and is connected to the cold water unit 3 by a cooling water pipe 7 to collect cold water generated in the cold water unit 3. The cooling water pipe 7 can circulate cold water between the cold water unit 3 and the cold water tank 10, and a circulation pump 8 is provided in the middle of the cooling water pipe 7. In the lower part of the cold water tank 10, there is provided a lower collecting chamber 12 for collecting the gas that has flowed in a plurality of heat transfer tubes of the first heat exchanger 4. The lower collecting chamber 12 has a role of turning a gas flow in the lower part of the cold water tank 10 to flow to the second heat exchanger 5 and a function of a drain tank for collecting drain generated by heat exchange. The ceiling surface of the lower collecting chamber 12 is a bottom plate of the cold water tank, and the lower ends of the heat transfer tubes of the first heat exchanger 4 and the second heat exchanger 5 reach the lower collecting chamber 12. A drain pipe 14 is connected to the bottom of the lower collecting chamber 12 so that the drain generated by the heat exchanger can be discharged through the drain pipe.

  The vacuum pipe 9 from the processing tank 2 is connected to the upper dispersion chamber 11 of the first heat exchanger 4, and the vacuum pipe 9 connected to the vacuum generator 1 is connected to the upper collecting chamber 13 of the second heat exchanger 5. The gas sucked from the treatment tank 2 passes through the first heat exchanger 4 and the second heat exchanger 5 and then reaches the vacuum generator 1. The first heat exchanger 4 connects the upper dispersion chamber 11 and the lower collecting chamber 12 with a large number of heat transfer tubes, and the second heat exchanger 5 also connects the upper collecting chamber 13 and the lower collecting chamber 12 with a large number of heat transfer tubes. It is what is connected. Therefore, the gas taken out from the processing tank 2 advances from the upper dispersion chamber 11 to the heat transfer tubes of the first heat exchanger 4 and gathers by entering the lower collecting chamber 12 provided below the cold water tank 10. . After that, after turning in the lower collecting chamber 12, it is divided into the heat transfer tubes of the second heat exchanger 5 and proceeds again. After gathering in the upper collecting chamber 13, it goes to the vacuum generator 1. Since the heat transfer tubes of the first heat exchanger 4 and the second heat exchanger 5 are installed through the water portion of the cold water tank 10, the outside of the heat transfer tubes is in contact with the cold water in the cold water tank 10.

In the lower gathering chamber 12, the lower gathering chamber 12 is divided into upper and lower parts, and a shielding plate 6 is provided on the bottom of the lower gathering chamber 12 to provide a drain water storage unit 16. The shielding plate 6 is provided with an opening for flowing the drain to the lower drain reservoir 16 on the side where the first heat exchanger 4 is provided, and the side where the second heat exchanger 5 is provided is connected to the peripheral wall. It is obstructed. The shielding plate 6 is provided with an inclination so that the height decreases toward the opening.

  The vacuum cooling operation in the embodiment will be described. First, as a preparation, an object to be cooled is accommodated in the processing tank 2 and the processing tank 2 is sealed. When the vacuum cooling operation is performed by operating the vacuum generator 1, the cold water unit 3, and the circulation pump 8, the gas in the processing tank 2 is taken out from the vacuum generator 1 through the vacuum pipe 9, and the processing tank 2. The pressure inside decreases. When the pressure in the treatment tank decreases, the water evaporates from the object to be cooled accommodated in the treatment tank 2, and when the water evaporates, the heat of vaporization is taken away from the surroundings. It goes down.

  The gas sent through the vacuum pipe 9 branches from the upper dispersion chamber 11 of the first heat exchanger 4 to the plurality of heat transfer tubes, flows downward, and travels toward the lower collecting chamber 12. The heat transfer tube is installed in the cold water tank 10 for storing low-temperature cold water. Since the outer surface of the heat transfer tube is in contact with the cold water, the heat transfer tube is cooled from the surroundings. Therefore, the gas flowing in the heat transfer tube proceeds while being cooled from the periphery of the heat transfer tube. The gas flowing downward in the first heat exchanger 4 turns in the lower collecting chamber 12 and flows toward the second heat exchanger 5 and flows upward in the lower collecting chamber 12. Since the heat transfer tube of the second heat exchanger 5 is also in contact with the cold water around it, the gas flowing in the second heat exchanger 5 is further cooled.

  When the gas is cooled by the first heat exchanger 4 and the second heat exchanger 5, the vapor contained in the gas is condensed, and the condensed water is transferred down the inner surface of the heat transfer tube and below the heat transfer tube. It flows down to the lower gathering chamber 12. When the steam becomes condensed water, the volume is significantly reduced. Therefore, the gas sucked from the treatment tank 2 is reduced in volume by the first heat exchanger 4 and further reduced in volume by the second heat exchanger 5. Therefore, the cross-sectional area of the gas flow path required in the second heat exchanger 5 is smaller than that of the first heat exchanger 4, and the number of heat transfer tubes installed in the second heat exchanger is the first heat exchanger 4. Can be less. When the volume of the gas is reduced, the amount of gas that must be exhausted by the vacuum generator 1 is reduced, so that the pressure in the treatment tank 2 can be reduced more quickly, and the time required for cooling can be shortened.

In this vacuum cooling device, the drain generated in the first heat exchanger 4 and the second heat exchanger 5 flows down into the lower collecting chamber 12. Since the shielding plate 6 is provided in the lower collecting chamber 12, the drain falls to the upper surface of the shielding plate 6, flows toward the opening along the surface of the shielding plate, and is below the shielding plate 6 from the opening. It flows down to the drain water storage section 16. Since there is a shielding plate 6 between the bottom of the lower collecting chamber 12 and the second heat exchanger 5, the drain accumulated in the drain reservoir 16 is prevented from being re-evaporated and sent to the second heat exchanger 5. can do.

In the conventional vacuum cooling apparatus, the drain generated in the first heat exchanger 4 and the second heat exchanger 5 is sent into a drain tank connected to the lower collecting chamber 12 by a drain pipe, so that a lower collecting chamber is obtained. 12, the drain is prevented from being re-evaporated and sent to the second heat exchanger 5. However, in the present invention, it is not necessary to install a drain tank separately. Cost can be reduced.

In the second embodiment shown in FIG. 3, the inclination angle is increased at the lower end of the shielding plate 6 provided in an inclined manner. A surface extending downward is provided at the tip of the shielding plate 6, and the space formed between the tip of the shielding plate 6 and the bottom surface of the lower collecting chamber 12 is narrow. A portion surrounded by the side surface and the bottom surface of the shielding plate 6 and the lower collecting chamber 12 is a drain water storage unit 16. An opening is provided between the front end of the shielding plate and the bottom surface of the lower collecting chamber to form a drain outlet, and the drain that has flowed down into the lower collecting chamber 12 is surrounded by the shielding plate 6 through the drain outlet. Enter the water reservoir 16.

The shielding plate 6 is provided with an air vent hole 15 at a position higher than the drain outlet. Therefore, even if the water level of the drain rises in the lower collecting chamber 12 and becomes higher than the drain outlet, the air in the drain water storage section 16 passes through the air vent hole 15, so that the drain is sent into the drain water storage section 16. Can do. In such a structure, when drain is accumulated in the drain reservoir, the drain outlet provided in the lower part is blocked by the drain, so that most of the drain is isolated by the part surrounded by the shielding plate 6. Become. The lower and upper sides of the shielding plate 6 in the lower collecting chamber 12 are connected by an air vent hole 15. However, since the opening area of the air vent hole 15 is small, the pressure above the shield plate 6 is reduced. A pressure difference is generated between the upper side and the lower side of the shielding plate 6. In the space below the shielding plate in the lower assembly chamber, the pressure drop is moderate, so that the drain accumulated in the drain reservoir 16 below the shielding plate 6 is difficult to evaporate, and the amount of generated steam is reduced.

  The present invention is not limited to the embodiments described above, and many modifications can be made by those having ordinary knowledge in the art within the technical idea of the present invention.

1 Vacuum generator
2 treatment tank
3 Cold water unit
4 First heat exchanger
5 Second heat exchanger
6 Shield plate
7 Cooling water piping
8 Circulation pump
9 Vacuum piping
10 Cold water tank
11 Upper dispersion chamber
12 Lower assembly room
13 Upper assembly room
14 Drain piping 15 Air vent hole 16 Drain water reservoir

Claims (3)

A processing tank that contains the object to be cooled, a vacuum generator connected to the processing tank by a vacuum pipe and sucking the gas in the processing tank, and a heat exchange that cools the gas sucked from the processing tank by the vacuum generator halfway In a vacuum cooling device that cools the object to be cooled by reducing the pressure inside the treatment tank,
The heat exchanger has a structure in which a first heat exchanger and a second heat exchanger are provided in this order in the gas suction path, and the first heat exchanger and the second heat exchanger are connected through a common lower collecting chamber,
The lower gathering chamber is provided with a shielding plate inside, the lower gathering chamber is divided into upper and lower parts by the shielding plate, the lower part of the lower gathering chamber is set as a drain reservoir, and the suction gas flowing from the first heat exchanger to the second heat exchanger Passes through the upper part of the lower collecting chamber, and the drain generated in the first heat exchanger and the second heat exchanger flows to the drain water storage part below the shielding plate. The shielding plate is the first heat exchange. An opening for dropping the drain to the bottom of the lower collecting chamber is provided on the side where the heat exchanger is installed, and no opening is provided on the side where the second heat exchanger is installed. A vacuum cooling device, wherein the vacuum cooling device is installed with an inclination so that the height decreases toward the part . In the vacuum cooling device according to claim 1 , the shielding plate has a surface extending in the lateral direction connected to the side wall surface in the lower assembly chamber on the root side and a surface extending downward on the tip side,
The surface extending downward from the front end side of the shielding plate is installed at a position close to the side surface facing the lower collecting chamber side surface connecting the shielding plate base side,
The space that occupies most of the lower part of the lower assembly room surrounded by the shielding plate and the side and bottom surfaces of the lower assembly room is used as a drain reservoir, and most of the drain in the lower assembly room is placed in the drain reservoir. A vacuum cooling device characterized by. The vacuum cooling device according to claim 1 or 2 , wherein a drain outlet for sending drain into the drain reservoir, and a drain reservoir in the space between the upper space of the lower collecting chamber and the drain reservoir provided in the lower portion. The vacuum cooling device is characterized in that the gas is communicated by an air vent hole for extracting the gas to the upper part in the lower collecting chamber, and the air vent hole is provided at a position higher than the drain outlet.

Images