JP2007162975A - Food machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a food machine for controlling a supply quantity of cooling water supplied to a heat exchanger corresponding to a change of a vapor generation quantity, a change of an object to be treated in type and a quantity and change of the cooling water in temperature in a cooling process. <P>SOLUTION: The food machine includes a treatment tank 2 for storing the object to be treated, a decompression means 5 for decompressing the inside of the treatment tank 2, the heat exchanger 6 for cooling vapor flowing to the decompression means 5 and a temperature adjusting valve 7 provided in a flow passage of the cooling water of the heat exchanger 6. The temperature adjusting valve 7 adjusts an opening corresponding to a temperature so as to increase a flow rate of the cooling water as the temperature of the cooling water in the heat exchanger 6 or after passing through the heat exchanger 6 rises and to decrease the flow rate of the cooling water as the temperature lowers. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a food machine including a heat exchanger configured to be capable of executing a step of reducing the pressure inside a processing tank in which an object to be processed is stored, and condensing steam sucked from the processing tank.

  Food machines such as vacuum cooling devices and vacuum cooking devices use the latent heat of vaporization when evaporating the moisture of the object to be processed by reducing the saturated steam temperature by reducing the pressure of the processing tank containing the object to be processed. And a step of cooling the object to be processed. In such a food machine, in order to increase the efficiency of decompression, the steam generated from the object to be processed is condensed by a heat exchanger and then decompressed by a decompression device such as a vacuum pump. In this case, a large amount of cooling water supplied to the heat exchanger is required to condense the steam.

  Therefore, in the following Patent Document 1, a method for reducing the cooling water supplied to the heat exchanger in the vacuum cooling device is proposed. In the method described in Patent Document 1, in the case of cooling the food that is the object to be treated, normally, immediately after the start of the pressure reduction of the treatment tank containing the food, almost no steam is generated from the food. Paying attention to the point that the amount of steam generated increases rapidly from the time when the temperature becomes lower than the food temperature, the elapsed time from the start of operation of the vacuum cooling device is measured by a timer device, and a predetermined time (for example, 1 minute) elapses. Until then, the cooling water is not supplied to the heat exchanger at all, and the supply of the cooling water is started after the predetermined time elapses, thereby reducing the cooling water.

  However, in the process of cooling the food that is the object to be processed, the amount and temperature of the steam generated from the object to be processed fluctuate over time, so the amount of cooling water required to condense the steam also changes greatly. To do. Nevertheless, in the method described in Patent Document 1, only the control of opening the cooling water control valve after a predetermined time has elapsed since the start of the operation of the vacuum cooling device is performed, and after the cooling water control valve is opened. Will always be supplied with a certain amount of cooling water. Therefore, in the method described in Patent Document 1, when the supply amount of cooling water is set to the amount of the period in which the cooling water is most needed in the cooling process, the cooling efficiency is ensured, but in other periods. The supply amount of cooling water becomes excessive, and the water saving effect cannot be expected. On the other hand, when water saving is emphasized and the supply amount of cooling water is set lower than the most required amount in the cooling process, the cooling efficiency is impaired, resulting in an increase in the time required for cooling.

  Furthermore, the method described in Patent Document 1 cannot cope with changes in the amount of steam generated due to differences in the type and amount of objects to be processed, and changes in the temperature of cooling water due to differences in seasons and climate, etc. A certain amount of cooling water will be supplied.

Moreover, in the vacuum thawing apparatus, in the air evacuation process in the treatment tank before or during thawing, the pressure is reduced while supplying steam, or the pressure is reduced by operating the steam ejector provided on the upstream side of the heat exchanger. To be done. For this reason, the heat exchanger for condensing a vapor | steam similarly to a vacuum cooling device is needed. When the method described in Patent Document 1 is applied to this vacuum thawing apparatus, a constant amount of cooling water is allowed to flow even when the feed water temperature is low, the supply amount of cooling water is excessive, and a water-saving effect is expected. become unable. On the other hand, if the supply amount of cooling water is set low with an emphasis on water saving, the pressure reduction efficiency will be impaired, resulting in an increase in time required for pressure reduction.
JP 2001-91120 A

  The problem to be solved by the present invention is to control the amount of cooling water supplied to the heat exchanger in response to changes in the temperature of the cooling water, thereby reducing the amount of cooling water used and further reducing the efficiency of decompression. This is to increase the pressure reduction time. In vacuum cooling, the amount of cooling water used can be reduced by controlling the amount of cooling water supplied to the heat exchanger in response to fluctuations in the load in the cooling process and changes in the type and amount of workpieces. In addition, the cooling efficiency is further improved to shorten the cooling time.

  This invention was made in order to solve the said subject, The invention of Claim 1 is the pressure reduction which performs the pressure reduction in the said processing tank via the processing tank in which a to-be-processed object is accommodated, and pressure reduction piping. Means, a heat exchanger for cooling the steam flowing in the decompression pipe, and a cooling water flow path of the heat exchanger, and the temperature of the cooling water passing through the heat exchanger or passing through the heat exchanger is high. And a temperature control valve that adjusts the opening according to the temperature so as to increase the flow rate of the cooling water as the temperature decreases and decrease the flow rate of the cooling water as the temperature decreases. It is a food machine.

  According to the first aspect of the present invention, the amount of cooling water supplied to the heat exchanger can be reduced by responding to load fluctuations in the decompression process, changes in the type and amount of the object to be processed, and changes in the temperature of the cooling water. Thus, the efficiency of decompression can be increased and the decompression time can be shortened.

  The invention described in claim 2 is a processing tank in which an object to be processed is accommodated, and means for reducing the pressure in the processing tank connected to the processing tank through a decompression pipe, and comprising a steam ejector. One of the pressure reducing means and the second pressure reducing means consisting of a pressure reducing device other than the steam ejector or only the second pressure reducing means, and provided between the processing tank or the first pressure reducing means and the second pressure reducing means. The heat exchanger for cooling the steam in the decompression pipe and the cooling water flow path of the heat exchanger are provided, and the temperature of the cooling water passing through the heat exchanger or passing through the heat exchanger is increased. Accordingly, a food machine comprising: a temperature control valve that adjusts an opening degree corresponding to the temperature so as to increase a flow rate of the cooling water and decrease the flow rate of the cooling water as the temperature decreases. It is.

  According to the second aspect of the present invention, the amount of cooling water supplied to the heat exchanger is reduced by responding to load fluctuations in the decompression process, changes in the type and amount of the object to be processed, and changes in the temperature of the cooling water. Thus, the efficiency of decompression can be increased and the decompression time can be shortened.

  According to a third aspect of the present invention, there is provided a processing tank in which an object to be processed is accommodated, a steam ejector connected to the processing tank via a decompression pipe, and an outlet of the steam ejector via the processing tank and the decompression pipe. A water-sealed vacuum pump connected to the side, a heat exchanger provided between the steam ejector and the water-sealed vacuum pump, for cooling the steam in the decompression pipe, and a cooling water outlet for the heat exchanger The amount of cooling water discharged is increased as the temperature of the cooling water passing through the heat exchanger increases, and the amount of cooling water discharged is decreased as the temperature decreases. And a temperature control valve for adjusting the opening degree.

  According to the third aspect of the present invention, it is possible to reduce the cooling water supplied to the heat exchanger, increase the efficiency of decompression, shorten the decompression time, and enable efficient decompression work.

  Further, in the invention according to claim 4, the temperature control valve is located in a flow path of the cooling water that has passed through the heat exchanger, and a substance that expands and contracts in accordance with the temperature of the cooling water is enclosed. The temperature sensor and the substance provided in the temperature sensor and moved by expansion or contraction corresponding to the temperature of the cooling water move to adjust the flow area of the cooling water. The food machine according to claim 1, further comprising a metering unit, wherein the metering unit allows a predetermined amount of cooling water to pass even in the most closed position. It is.

  According to the fourth aspect of the present invention, since it is not necessary to electrically control the flow rate of cooling water using a temperature sensor, it is possible to realize a food machine with few failures and low costs.

  According to the present invention, by controlling the amount of cooling water supplied to the heat exchanger in response to fluctuations in the load in the cooling process, changes in the type and amount of the object to be processed, and changes in the temperature of the cooling water, The amount of water used can be reduced, and the decompression time can be shortened by increasing the efficiency of decompression.

  Next, an embodiment of the present invention will be described. The present invention relates to a food machine such as a vacuum cooling device, a vacuum cooking device, and a vacuum thawing device. However, the present invention is configured to execute a step of reducing the pressure in the processing tank in which the object to be processed is stored, and heat exchange for cooling and condensing the steam sucked from the processing tank and / or the steam from the steam ejector. Any food machine equipped with a bowl can be used regardless of the type. Moreover, typically as a to-be-processed object in a vacuum cooling device, food cooked by cooking, such as soup, fried food, and cooked rice, is mentioned, but the kind in particular is not limited.

  The food machine according to the present embodiment includes a processing tank in which an object to be processed is stored, a decompression unit that decompresses the inside of the processing tank via a decompression pipe, a heat exchanger that cools steam flowing in the decompression pipe, It is provided in the cooling water flow path of the heat exchanger, and increases the flow rate of the cooling water as the temperature of the cooling water passing through the heat exchanger or through the heat exchanger increases, and as the temperature decreases. It is a vacuum cooling device provided with the temperature control valve which adjusts an opening degree corresponding to the said temperature so that the flow volume of cooling water may be decreased.

  The said processing tank is a hollow container which accommodates to-be-processed object and can be sealed, and the opening position for taking in / out a to-be-processed object is not specifically limited. The treatment tank of the present embodiment has a hollow box shape that can be opened and closed by a door.

  The decompression means is means for decompressing the inside of the processing tank by sucking and exhausting the air in the processing tank to the outside. Examples of the pressure reducing means include a vacuum pump and an ejector, but the kind thereof is not limited. Moreover, this decompression means may be constituted by one decompression device, or may be constructed by combining a plurality of or a plurality of types of decompression devices. Preferably, as the decompression means, a first decompression means comprising a steam ejector connected to the treatment tank via a decompression pipe, and a second decompression means comprising a water ring vacuum pump connected to the outlet side of the steam ejector. Can be combined.

  The heat exchanger cools and condenses the steam discharged from the treatment tank and flowing to the decompression means. The heat exchanger includes heat exchange means such as a coil, and is connected to a cooling water supply pipe to be supplied with cooling water. When the pressure reducing means is composed of a steam ejector connected to the treatment tank via a pressure reducing pipe and a water-sealed vacuum pump connected to the outlet side of the steam ejector via the pressure reducing pipe, a heat exchanger Is preferably provided between the steam ejector and the water ring vacuum pump. Moreover, normal temperature water can be used as the cooling water, or a chiller can be provided as a water supply means connected to the upstream side of the cooling water supply pipe, and the cold water cooled by the chiller can be used.

  The temperature control valve is provided in the cooling water flow path of the heat exchanger, and increases the flow rate of the cooling water as the temperature of the cooling water passing through the heat exchanger or passing through the heat exchanger increases. The opening degree is adjusted corresponding to the temperature so as to decrease the flow rate of the cooling water as the temperature decreases. It is preferable that the temperature control valve is configured such that the maximum flow rate of cooling water obtained when the opening degree is maximized can supply the most required amount of cooling water in the decompression step, that is, the cooling step. Thereby, the pressure reduction, that is, the cooling efficiency can be further improved, and the pressure reduction time, that is, the cooling time can be shortened. Moreover, the structure of this temperature control valve will not be specifically limited if the flow volume can be adjusted according to the said temperature. For example, a temperature sensor is provided in the heat exchanger or downstream of the heat exchanger, the temperature of the cooling water is detected by the temperature sensor, and the opening degree of the temperature control valve is adjusted based on the detected temperature. It may be configured. At this time, the temperature control valve may be arranged on the cooling water supply pipe on the upstream side of the heat exchanger, or may be arranged on the cooling water drain pipe on the downstream side.

  Preferably, the temperature control valve is positioned in a flow path of the cooling water that has passed through the heat exchanger, and a temperature sensing part in which a substance that expands and contracts according to the temperature of the cooling water is enclosed, and the temperature sensing part A metering unit that adjusts the flow passage area of the cooling water by moving or expanding and contracting the substance enclosed in the temperature sensing unit corresponding to the temperature of the cooling water, The metering unit may be configured to allow passage of a predetermined amount of cooling water even in the most closed position. The temperature control valve having such a configuration is provided on the downstream side of the heat exchanger. The substance enclosed in the temperature sensing part typically includes wax, but the thermal expansion to such an extent that the flow area of the cooling water can be adjusted by moving the metering part provided in the temperature sensing part. The type is not limited as long as it has a reversible property that shrinks in accordance with the temperature when the temperature is high and the temperature of the cooling water decreases. In addition, the metering unit of the present embodiment has a water passage hole through which cooling water can pass, and allows passage of a predetermined amount of cooling water by preventing the water passage hole from being completely closed even in the most closed position. However, the present invention is not limited to this configuration, and any structure that allows passage of a predetermined amount of cooling water even at the most closed position may be used. Further, the metering part may be provided by being integrally formed with the temperature sensing part, or may be provided by connecting another member. By the way, the reason that the metering unit allows the cooling water to pass even in the closed position is to detect the temperature of the cooling water that has passed through the heat exchanger without delay in the temperature sensing unit, and the amount is It can be changed as appropriate.

  The embodiment of the present invention is not limited to the vacuum cooling device described above, but includes an embodiment of a vacuum thawing device. This vacuum thawing apparatus is an apparatus that keeps the inside of a processing tank at a low pressure, supplies steam, and defrosts an object to be processed (an object to be thawed). In the air evacuation process and the thawing process in the treatment tank before thawing in the vacuum thawing apparatus, the pressure is reduced while supplying steam, or the pressure is reduced by operating the steam ejector provided on the upstream side of the heat exchanger. Is called.

  The vacuum thawing device can have the same configuration as the vacuum cooling device. Specifically, a processing tank in which an object to be processed is accommodated, a decompression unit that decompresses the inside of the treatment tank via a decompression pipe, a heat exchanger that cools steam flowing in the decompression pipe, and the heat exchanger The flow rate of the cooling water is increased as the temperature of the cooling water in the heat exchanger or passed through the heat exchanger increases, and the cooling water is decreased as the temperature decreases. And a temperature control valve that adjusts the opening according to the temperature so as to reduce the flow rate.

  In this vacuum thawing device, the difference from the vacuum cooling device is that, instead of the vacuum cooling step, the pressure reducing means is operated to depressurize the inside of the processing tank to discharge air and vapor, and after this step, the pressure reducing means Is operated to supply a vapor while keeping the inside of the treatment tank at a low pressure below atmospheric pressure, and to perform a thawing step of thawing the object to be treated with the low-pressure vapor. About each component of this vacuum thawing apparatus, the structure similar to the said vacuum cooling apparatus is employable.

  According to the embodiment of this vacuum thawing device, when the feed water temperature is low, the supply amount of cooling water can be reduced, the decompression efficiency can be improved, and the time required for decompression can be shortened.

  Hereinafter, specific embodiments in which the present invention is applied to a vacuum cooling apparatus will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of the vacuum cooling device of Example 1, FIG. 2 is a diagram showing a temperature control valve when the metering unit is in the most closed position, and FIG. 3 is a diagram of cooling water that has passed through the heat exchanger. FIG. 4 is a diagram illustrating a temperature control valve when the temperature rises, and FIG. 4 illustrates the pressure in the treatment tank, the temperature of cooling water on the heat exchanger inlet side, and the cooling on the heat exchanger outlet side in the vacuum cooling apparatus of Example 1. It is a figure which shows the outline of the temperature of water, and the flow volume change of cooling water.

  As shown in FIG. 1, the vacuum cooling apparatus 1 according to the present embodiment includes a processing tank 2 that accommodates a food that is an object to be processed, a vapor ejector 3 that depressurizes the processing tank 2, and a decompression unit 5 that includes a vacuum pump 4. And a heat exchanger 6 that cools the steam, a temperature control valve 7 that adjusts the flow rate of the cooling water supplied to the heat exchanger 6, and a return pressure that returns the pressure in the treatment tank 2 that has been decompressed by introducing outside air. Means 8. The operations of the decompression unit 5 and the decompression unit 8 are controlled based on a control signal from the control unit 9.

  The processing tank 2 has a hollow box shape that can be opened and closed by a hermetically sealed door (not shown), and stores food as an object to be processed. The treatment tank 2 is connected to a decompression means 5 that evacuates the air in the treatment tank 2 to decompress the inside of the treatment tank 2 via a decompression pipe 10. In addition, the processing tank 2 includes an outside air introduction pipe 12 that can communicate with the outside air via the sterilization filter 11, and a return pressure control valve 13 provided in the middle of the outside air introduction pipe 12. A return pressure means 8 for returning the pressure to the atmospheric pressure is connected.

  In this embodiment, the decompression means 5 is composed of a steam ejector 3 as a first decompression means and a vacuum pump 4 as a second decompression means. In the steam ejector 3, the steam inlet 14 is connected to a boiler (not shown) via a steam supply pipe 15, the suction port 16 is connected to the treatment tank 2 via a decompression pipe 10, and the outlet 17 is connected to the decompression pipe 10. And is connected to the vacuum pump 4.

  A steam supply control valve 18 is provided in the middle of the steam supply pipe 15. The steam supply control valve 18 may be a valve that only switches between opening and closing, such as an electromagnetic valve, but a valve capable of adjusting the opening, such as a proportional control valve or a motor valve, may be used. When the steam supply control valve 18 can be adjusted in opening, not only the presence / absence of steam supply to the steam inlet 14 of the steam ejector 3 but also the amount of steam supply can be changed to adjust the decompression capacity.

  As the vacuum pump 4, a water ring vacuum pump is used in this embodiment. The sealed water of the vacuum pump 4 is supplied through a sealed water supply pipe 20 that branches in the middle of the cooling water supply pipe 19, and the drainage of the vacuum pump 4 is drained through a sealed water drain pipe 21 (not shown). ).

  The decompression pipe 10 between the steam ejector 3 and the vacuum pump 4 is provided with a heat exchanger 6 and a check valve 22. The heat exchanger 6 includes a coil 23 as heat exchange means. Cooling water is supplied to the coil 23 via the cooling water supply pipe 19, and when the cooling water passes through the coil 23, the steam flowing into the heat exchanger 6 via the decompression pipe 10 is cooled and condensed. Is done. The cooling water that has passed through the heat exchanger 6 is discharged to a drain outlet (not shown) through a cooling water drain pipe 24 connected to a coil 23 inside the heat exchanger 6. In this embodiment, room temperature water obtained from a well or water supply is used as cooling water.

  Thus, by providing the heat exchanger 6 between the steam ejector 3 and the vacuum pump 4, the steam is injected from the steam inlet 14 to the outlet 17 of the steam ejector 3 while the vacuum pump 4 is operated, A fluid mixture obtained by mixing the steam generated from the processed product and the steam supplied to the steam ejector 3 is cooled and condensed by the heat exchanger 6. Thus, since the air in the processing tank 2 is sucked and discharged to the outside by the steam ejector 3 and the vacuum pump 4, the inside of the processing tank 2 can be effectively decompressed.

  A temperature control valve 7 is provided in the middle of the cooling water drain pipe 24 to adjust the opening degree in accordance with the temperature of the cooling water that has passed through the heat exchanger 6. 2 and 3, the temperature control valve 7 is connected to the temperature sensing unit 25, the metering unit 26 coupled to the temperature sensing unit 25, and the base end side of the temperature sensing unit 25. A coil spring 27 that biases the portion 25 in the distal direction is housed in a valve box 28.

  In the valve box 28, the upper surface side of the valve box 28 is opened, and a vertical hole 29 for accommodating the spring 27, the temperature sensing unit 25, and the metering unit 26 is formed. The opening of the vertical hole 29 accommodates the spring 27, the temperature sensing unit 25, and the metering unit 26 and is closed with a lid 31 through an O-ring 30. The lid 31 is in contact with one end of the spring 27. In addition, the valve box 28 is formed with an inlet 32 and an outlet 33 for cooling water connected to the vertical hole 29 substantially perpendicularly. The inlet 32 of the valve box 28 is connected to the outlet 34 of the heat exchanger 6 via the cooling water drain pipe 24, and the outlet 33 of the valve box 28 is connected to the drain outlet (not shown) via the cooling water drain pipe 24. ing. The inlet 32 and the outlet 33 are formed in steps, and the inlet 32 is provided at substantially the same height as the temperature sensing portion 25, and the outlet 33 is provided at substantially the same height as the bottom 35 of the valve box 28. It has been. A rod-shaped fixed shaft 36 is provided on the bottom 35 of the valve box 28 so as to protrude substantially vertically upward.

  The temperature sensing part 25 has a flange-shaped water stop part 37 formed on the base end side, and a metering part 26 connected to the tip side. Inside the temperature sensing unit 25, a wax that expands as the temperature increases and contracts as the temperature decreases is enclosed. A pin 38 is provided inside the temperature sensing unit 25. The pin 38 is configured to protrude toward the distal end of the temperature sensing portion 25 when the wax is heated and expands. Further, an insertion hole 39 through which the fixed shaft 36 provided in the bottom portion 35 of the valve box 28 is inserted is opened along the axial direction on the distal end side of the temperature sensing portion 25, and the distal end of the fixed shaft 36 is inserted through the insertion portion 39. The tip of the pin 38 of the temperature sensing unit 25 is in contact with the inside of the hole 39.

  The metering section 26 is formed in a cross-sectional shape that matches the vertical hole 29 of the valve box 28, and water is stopped at the contact surface with the peripheral side surface of the vertical hole 29 of the valve box 28. The metering section 26 is provided with a water passage hole 40 that allows the cooling water flowing from the inlet 32 of the valve box 28 to pass through and flow out from the outlet 33.

  Here, the operation of the temperature control valve 7 of the present embodiment will be described. The cooling water that has passed through the heat exchanger 6 flows into the valve box 28 from the inlet 32 of the valve box 28. At this time, since the base end side of the temperature sensing unit 25 is stopped by the water stop unit 37, the cooling water flowing into the valve box 28 changes the flow direction to the tip side of the temperature detection unit 25. Then, it passes through the water passage hole 40 of the metering section 26 and flows to the outlet 33 of the valve box 28. With this configuration, the temperature sensing unit 25 is positioned in the flow path of the cooling water that has passed through the heat exchanger 6, so that the temperature of the cooling water can be reliably detected.

  In the present embodiment, room temperature water is used as cooling water, so that when the cooling water flowing into the valve box 28 is in the vicinity of room temperature, the metering unit 26 is configured to be in the most closed position. Yes. That is, as shown in FIG. 2, since the wax enclosed in the temperature sensing portion 25 is contracted, the pin 38 of the temperature sensing portion 25 does not protrude, and the temperature sensing portion 25 is connected to the base end side. Since the spring 27 is biased toward the distal end, the metering unit 26 connected to the distal end side of the temperature sensing unit 25 is located at the most closed position where the flow rate of the cooling water is minimized. Of course, even when the metering unit 26 is in the most closed position, the gap X is slightly formed between the metering unit 26 and the bottom 35 of the valve box 28, and the operation of the vacuum cooling device 1 is performed. A predetermined amount of cooling water is always allowed to pass through.

  When the temperature of the cooling water flowing into the inside of the valve box 28 rises, the wax enclosed in the temperature sensing unit 25 expands corresponding to the temperature, and the pin 38 of the temperature sensing unit 25 is moved as shown in FIG. It protrudes toward the tip of the temperature sensing part 25. Therefore, the tip of the pin 38 pushes the tip of the fixed shaft 36 provided at the bottom portion 35 of the valve box 28 that is in contact with the inside of the insertion hole 39 formed at the tip of the temperature sensing portion 25, and the reaction causes the temperature sensing. The part 25 moves away from the bottom part 35. Then, the metering unit 26 connected to the tip of the temperature sensing unit 25 also moves away from the bottom 35, and the gap X between the metering unit 26 and the bottom 35 increases. As a result, the flow rate of cooling water increases. Thus, the temperature control valve 7 in this embodiment adjusts the flow rate of the cooling water supplied to the heat exchanger 6 in response to the temperature change of the cooling water that has passed through the heat exchanger 6. By the way, the temperature control valve 7 of the present embodiment is not only in the state where the opening of the vertical hole 29 is directed upward as shown in FIGS. 2 and 3, but in other directions, for example, in the state where the opening is directed laterally or downward. Can also be used.

  Next, the operation of the temperature control valve 7 will be described in correspondence with the temperature change of the cooling water accompanying the operation of the vacuum cooling device 1 of the present embodiment. FIG. 4 is a diagram showing an outline of changes in the flow rate of cooling water in the cooling process of the vacuum cooling apparatus of the present embodiment, where the dotted line is the pressure in the processing tank (internal pressure), and the alternate long and short dash line is the inlet of the heat exchanger The temperature of the cooling water (heat exchange inlet temperature) in FIG. 1, the solid line indicates the temperature of the cooling water that has passed through the heat exchanger (heat exchange outlet temperature), and the two-dot chain line indicates the flow rate (flow rate) of the cooling water.

  When the food that is the object to be processed is cooled by the vacuum cooling device 1 of the present embodiment, first, the object to be processed is stored in the processing tank 2, the door is closed and sealed, and then the control unit 9 turns off the vacuum pump 4. The pressure in the processing tank 2 is started by operating. In addition, water supply from the water supply means (not shown) to the heat exchanger 6 and the vacuum pump 4 is started, but almost no steam is generated from the object to be processed immediately after the operation of the vacuum cooling device 1 is started. As shown in Fig. 5, the heat exchange outlet temperature hardly changes and remains at the heat exchange inlet temperature, that is, a temperature close to room temperature. At this time, the metering unit 26 in the temperature control valve 7 is in the most closed position, and the cooling water supplied to the heat exchanger 6 senses the temperature without delay in the temperature sensing unit 25 of the temperature control valve 7. The flow rate is limited to that required.

  The inside of the treatment tank 2 is decompressed as it is, and when the saturated vapor temperature becomes equal to or lower than the food temperature and the evaporation of moisture from the treatment object starts, heat begins to be rapidly deprived from the treatment object. At this time, since a large amount of steam flowing into the heat exchanger 6 through the decompression pipe 10 is cooled and condensed in the heat exchanger 6, the heat exchange outlet temperature rapidly increases. Corresponding to this heat exchange outlet temperature, the wax enclosed in the temperature sensing part 25 of the temperature control valve 7 expands rapidly, and the metering part 26 of the temperature control valve 7 increases in a direction away from the bottom 35 of the valve box 28. Moving. As a result, the flow rate of the cooling water supplied to the heat exchanger 6 increases abruptly, and the amount of cooling water necessary for cooling the steam at that time is supplied to the heat exchanger 6. Therefore, the cooling efficiency is improved and the cooling time to the target value can be shortened.

  Thereafter, when the pressure reduction in the processing tank 2 proceeds, the temperature of the steam generated from the object to be processed decreases. If it does so, in the heat exchanger 6 which uses normal temperature water as cooling water, it will become impossible to cool and condense steam, and only the vacuum pump 4 which uses normal temperature water as sealing water will not be able to depressurize in the processing tank 2. Therefore, the control unit 9 opens the steam supply control valve 18 at a time slightly before the heat exchanger 6 cannot condense the steam (time T1 in FIG. 4). Thus, steam is supplied from the boiler (not shown) to the steam ejector 3 via the steam supply pipe 15, and the steam ejector 3 starts to operate. As described above, the operation start time of the steam ejector 3 is delayed with respect to the operation start time of the vacuum pump 4 when the time when the steam ejector 3 is started simultaneously with the vacuum pump 4 is reduced to the target internal pressure. This is because it becomes longer. In the present embodiment, the operation of the steam ejector 3 is started when the internal pressure detected by the pressure sensor (not shown) reaches a set value, but the operation is performed based on other detected values. It can also be made to start, an elapsed time from the start of operation of vacuum cooling device 1 can be measured with a timer device, and operation can also be started after the set time has passed.

  After the start of the operation of the steam ejector 3, the steam supplied to the steam ejector 3 and the steam evaporated from the object to be processed are mixed to flow into the heat exchanger 6. The mixed fluid is maintained at a temperature higher than normal temperature, and the mixed fluid containing steam is cooled and condensed by the heat exchanger 6 and discharged by the vacuum pump 4. As described above, after the operation of the steam ejector 3 is started, the inside of the processing tank 2 is efficiently decompressed by the steam ejector 3 and the vacuum pump 4.

  In addition, the temperature of the heat exchanger outlet temperature after the operation of the steam ejector 3 becomes substantially constant, and the temperature control valve 7 that has once increased the flow rate of the cooling water abruptly, the wax in the temperature sensing unit 25 gradually becomes the heat exchanger outlet. By shrinking to the volume corresponding to the temperature, the flow rate of the cooling water is decreased. Thus, since the vacuum cooling device 1 of the present embodiment adjusts the amount of cooling water supplied to the heat exchanger 6 by the temperature control valve 7, the cooling water can be reduced.

  And when the temperature of the to-be-processed object falls to the target value, the control unit 9 opens the return pressure control valve 13, introduces the outside air that has passed through the sterilization filter 11 into the treatment tank 2 through the outside air introduction pipe 12, The pressure in the processing tank 2 is restored. At the same time, the supply of the cooling water and the sealing water by the water supply means is stopped, and the cooling process is terminated.

  Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic configuration diagram of the vacuum cooling device 1 according to the second embodiment. The same members as those in the first embodiment are denoted by the same reference numerals.

  In the present embodiment, the temperature control valve 7 in the first embodiment includes the temperature sensor 42 provided in the cooling water drain pipe 24 on the downstream side of the heat exchanger 6 and the cooling water supply pipe 19 on the upstream side of the heat exchanger 6. This is replaced with a flow rate adjusting valve 43 that adjusts the flow rate of the cooling water supplied to the heat exchanger 6.

  The controller 9 detects the temperature of the cooling water that has passed through the heat exchanger 6 by the temperature sensor 42 and adjusts the opening degree of the flow rate adjustment valve 43 based on the detected temperature. That is, when the temperature of the cooling water detected by the temperature sensor 42 increases, the flow rate adjustment valve 43 increases the opening degree and increases the flow rate corresponding to the temperature. On the other hand, when the temperature of the cooling water detected by the temperature sensor 42 decreases, the flow rate adjustment valve 43 decreases the opening degree and decreases the flow rate corresponding to the temperature.

  The temperature sensor 42 may be provided in the heat exchanger 6. The flow rate adjusting valve 43 is provided in the cooling water supply pipe 19 on the upstream side of the heat exchanger 6, which is provided on the downstream side of the heat exchanger 6 and on the downstream side of the temperature sensor 42. May be provided. The flow rate adjusting valve 43 is not particularly limited as long as the flow rate of the cooling water can be adjusted.

  The embodiment of the present invention has been described above, but the present invention is not limited to the configuration of the embodiment, and can be changed as appropriate. For example, the temperature control valve 7 is not limited to the configuration of the above embodiment, and may have another configuration. Moreover, in the said Example, normal temperature water was used as the cooling water of the heat exchanger 6, However, A chiller can be provided as a water supply means, and cold water can also be used. Furthermore, in the said Example, although the steam ejector 3 is used as a 1st pressure reduction means, it is also omissible. Furthermore, in the said Example, although the operation start time of the steam ejector 3 is delayed from the operation start time of the vacuum pump 4, you may operate both simultaneously. Furthermore, the present invention can also be applied to a vacuum thawing apparatus.

It is a schematic block diagram of the vacuum cooling device in Example 1 of this invention. It is a figure which shows a temperature control valve when a metering part exists in a most closed position. It is a figure which shows the temperature control valve of the state which the temperature of the cooling water which passed the heat exchanger rose. It is a figure which shows the outlines, such as a flow volume change of the cooling water in the vacuum cooling device of Example 1. FIG. It is a schematic block diagram of the vacuum cooling device in Example 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum control apparatus 2 Processing tank 3 Steam ejector 4 (Water seal type) vacuum pump 6 Heat exchanger 7 Temperature control valve 10 Pressure-reducing piping 25 Temperature sensing part 26 Metering part

Claims (4)

A treatment tank in which an object to be treated is accommodated;
Pressure reducing means for reducing the pressure in the processing tank via a pressure reducing pipe;
A heat exchanger for cooling the steam flowing in the decompression pipe;
As the temperature of the cooling water provided in the cooling water flow path of the heat exchanger and passing through the heat exchanger or through the heat exchanger increases, the flow rate of the cooling water is increased and the temperature becomes lower. Therefore, a food machine comprising: a temperature control valve that adjusts an opening degree corresponding to the temperature so as to reduce a flow rate of cooling water. A treatment tank in which an object to be treated is accommodated;
A means for reducing the pressure in the treatment tank connected to the treatment tank via a decompression pipe, both of a first decompression means comprising a steam ejector and a second decompression means comprising a decompression device other than the steam ejector. Or only the second decompression means,
A heat exchanger that is provided between the treatment tank or the first decompression means and the second decompression means, and cools the steam in the decompression pipe;
As the temperature of the cooling water provided in the cooling water flow path of the heat exchanger and passing through the heat exchanger or through the heat exchanger increases, the flow rate of the cooling water is increased and the temperature becomes lower. Therefore, a food machine comprising: a temperature control valve that adjusts an opening degree corresponding to the temperature so as to reduce a flow rate of cooling water. A treatment tank in which an object to be treated is accommodated;
A steam ejector connected to the treatment tank via a decompression pipe;
A water-sealed vacuum pump connected to the outlet side of the steam ejector via the treatment tank and the decompression pipe;
A heat exchanger provided between the steam ejector and the water ring vacuum pump for cooling the steam in the decompression pipe;
Provided on the cooling water outlet side of the heat exchanger, the cooling water drainage amount increases as the temperature of the cooling water passing through the heat exchanger increases, and the cooling water drainage amount decreases as the temperature decreases. A food control machine comprising: a temperature control valve that adjusts an opening degree corresponding to the temperature. The temperature control valve is
A temperature sensing part that is located in a flow path of cooling water that has passed through the heat exchanger, and in which a substance that expands and contracts in accordance with the temperature of the cooling water is enclosed;
A metering unit that is provided in the temperature sensing unit and moves when the substance enclosed in the temperature sensing unit expands or contracts according to the temperature of the cooling water to adjust the flow passage area of the cooling water. ,
The food meter according to any one of claims 1 to 3, wherein the metering unit allows a predetermined amount of cooling water to pass even in the most closed position.

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