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(11) | EP 3 054 240 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | An apparatus for supplying refrigerated fluid |
| (57) An apparatus (1) for supplying refrigerated fluid, comprising a compressor (2) for
compressing a refrigerant fluid, a condenser (3) for condensing the compressed refrigerant
fluid, an expansion valve (4) for expanding the condensed refrigerant fluid, an evaporator
(5) that allows the expanded refrigerant fluid to cool a fluid entering through an
inlet pipe (IN) for delivering a refrigerated fluid to an outlet pipe (OUT), characterised
in that it comprises a branch (6) connected in parallel to the expansion valve (4),
the branch (6) comprises a valve (7) in fluid communication with the condenser (3)
and a capillary tube (8) in fluid communication with the valve (7), the valve (7)
is configured to be set in an open configuration and in a closed configuration, the
open configuration allows the flow of refrigerant fluid through the capillary tube
(8) to put the evaporator (5) in fluid communication with the capillary tube (8),
the closed configuration prevents the flow of refrigerant fluid through the capillary
tube (8).
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Field of the invention
[0001] The present invention relates to the field of supplying refrigerated fluid for controlling the temperature of food liquids, for example chillers for controlling the temperature of wine must during winemaking.
Background of the invention
[0002] Control of the temperature of food liquids is important in the food industry, for example wineries and breweries. An apparatus for supplying refrigerated fluid, such as a chiller, is a machine that removes heat from a fluid via a vapour-compression. This refrigerated fluid produced by the chiller can then be circulated through a heat exchanger to cool water, air or equipment as required. In general, refrigeration creates waste heat that must be exhausted to ambient or recovered for heating purposes.
[0003] Chillers comprise a refrigeration compressor which is essentially a pump for refrigerant gas. The capacity of the compressor, and hence the chiller cooling capacity can be measured in kilowatts input (kW). The mechanism for compressing refrigerant gas differs between compressors, depending on the application. Examples of compressors that can be employed for a refrigeration apparatus are rotary compressors, scroll compressors and screw compressors.
[0004] A chiller also comprises a condenser which can be air cooled, water cooled, or evaporative. The condenser is a heat exchanger which allows heat to migrate from the refrigerant gas to either water or air. Air cooled condenser are manufactured from copper tubes (for the refrigerant flow) and aluminium fins (for the air flow). Each condenser has a different material cost and they vary in terms of efficiency.
[0005] A chiller also comprises an expansion device or refrigerant metering device (e.g., expansion valve) configured to restrict the flow of the refrigerant fluid causing a pressure drop that vaporizes some of the refrigerant. The vaporization absorbs heat from nearby liquid refrigerant, cooling down the refrigerant liquid.
[0006] The expansion device is located immediately prior to an evaporator so that the cold gas in the evaporator can absorb heat from the water flowing through the evaporator.
[0007] The evaporator is a heat exchanger which allows the heat energy to migrate from the water stream into the refrigerant gas. During the state change of the remaining liquid to gas, the refrigerant can absorb large amounts of heat without changing temperature.
[0008] The expansion device is designed to function in a specific range of temperatures based on the chiller cooling capacity, and the compressor power.
[0009] For example, the power of the compressor (e.g., measured in Kw) allows the cooling of a fluid, such as water, in a range of temperature comprised between -4°C and +4°C. In other words, every component of the chiller (e.g., expansion valve) is specifically designed for delivering a refrigerated fluid (e.g., water) within a restricted range of temperatures (usually -4°C<T<+4°C).
[0010] With reference to the example mentioned above, the chiller would not be able to cool water at higher temperatures (i.e., higher power of the compressor), such as 7°C, without relevant loss of efficiency. In fact, the expansion valve would be overheated and the values of evaporation of the refrigerant fluid would be too low because the valve is designed to work with lower values of compressor power.
[0011] The chillers known from the state of the art cannot be employed in applications (e.g., during winemaking) that require a wide range of temperatures (e.g., -8°C ≤ T ≤ +12°C) of the cool water produced by the evaporator.
[0012] The applicant sensed that it would be convenient to develop a chiller which is able to overcome the above mentioned disadvantages of chillers known from the prior art. Therefore, there is a need for a reliable, effective and efficient apparatus able to deliver refrigerated fluid in a wide range of temperatures, for instance to control the temperature of food liquids.
Summary of the invention
[0013] The present invention relates to an apparatus for supplying refrigerated fluid for controlling temperature of a food liquid according to claim 1.
Brief description of the drawings
[0014] The present invention will now be described in more detail hereinafter with reference to the accompanying drawings, in which some embodiments of the invention are shown.
FIG. 1 is a schematic view of an apparatus according to one embodiment of the present invention,
FIG. 2 is a schematic view of the apparatus of FIG. 1 connected to a heat exchanger, which is not part of the present invention,
FIG. 3 is a schematic view of an apparatus according to one embodiment of the present invention, in particular operating conditions.
Detailed description
[0015] Figure 1 shows an apparatus 1 for supplying refrigerated fluid for controlling the temperature of a food liquid.
[0016] The apparatus 1 comprises a compressor 2 configured for compressing a refrigerant fluid (i.e., to increase the pressure of the refrigerant fluid), and a condenser 3 in fluid communication with the compressor 2. The condenser 3 is configured for condensing the refrigerant fluid compressed by the compressor 2, to cool down the refrigerant fluid.
[0017] The apparatus 1 comprises an expansion valve 4 in fluid communication with the condenser 3. The expansion valve 4 is configured for expanding the refrigerant fluid (i.e., decrease of pressure of the refrigerant fluid) condensed by the condenser 3.
[0018] The apparatus 1 further comprises an evaporator 5 including an inlet pipe IN and an outlet pipe OUT. The inlet pipe IN is in fluid communication with the outlet pipe OUT. The evaporator 5 is connected with the expansion valve 4 to allow the refrigerant fluid expanded by the expansion valve 4 to cool a fluid entering through the inlet pipe IN, for delivering a refrigerated fluid to the outlet pipe OUT.
[0019] Preferably, the "warm" fluid is water, or air, entering through the inlet pipe IN of the evaporator 5, in order to be refrigerated by the refrigerant fluid flowing through the evaporator 5. The evaporator 5 delivers the "cold" fluid (e.g., water or air) to the outlet pipe OUT.
[0020] Preferably, a heat exchanger 13 is connected to the inlet pipe IN and the outlet pipe OUT, for example, for cooling the food liquid (e.g., wine must during winemaking) stored in a tank (figure 2). According to this example, the heat exchanger 13 is operatively coupled with a heat pump equipment to supply refrigerated fluid (e.g., water) to the heat exchanger for cooling the food liquid stored in the tank.
[0021] In another example, a heat exchanger 13 is connected to the inlet pipe IN and to the outlet pipe OUT, and employs a refrigerated fluid, such as air, for cooling a room.
[0022] The evaporator 5 is connected with the compressor 2 to supply refrigerant fluid to the compressor 2.
[0023] The apparatus 1 comprises a branch 6 connected in parallel to the expansion valve 4. The branch 6 comprises a valve 7 in fluid communication with said condenser 3, and a capillary tube 8 in fluid communication with the valve 7.
[0024] The valve 7 is configured to be set in an open configuration and in a closed configuration. The open configuration allows the flow of refrigerant fluid through the capillary tube 8, in order to put the evaporator 5 in fluid communication with the capillary tube 8. The closed configuration prevents the flow of refrigerant fluid through the capillary tube 8.
[0026] Preferably, the compressor 2 is one chosen from a rotary compressor or a scroll compressor or a screw compressor.
[0028] Preferably, the expansion valve 4 is a thermostatic valve designed for delivering refrigerated water to the outlet pipe OUT at a temperature ranging from -8°C to +4°C. In other words, when the valve 7 is set in the closed configuration, the lamination of the refrigerant fluid occurs only through the expansion valve 4 (e.g., thermostatic valve).
[0029] Moreover, when the valve 7 is set in the open configuration, the lamination of the refrigerant fluid occurs both through the expansion valve 4 and through the capillary tube 8. In this way the temperature of the refrigerated water to be delivered on the outlet pipe OUT can be higher than the temperature obtained through the expansion valve 4 itself, for example from +4°C to +7°C. In fact, the lamination effect provided by the expansion valve 4 would not be sufficient to refrigerate water at temperatures above +4°C because the expansion valve 4 is designed to work with lower temperatures (i.e., lower power of the compressor 2).
[0030] Advantageously, an apparatus 1 comprising a branch 6 including a valve 7 and a capillary tube 8 can deliver refrigerated water to the outlet pipe OUT in a wide temperature range (e.g., +4°C<T<+12°C).
[0032] According to an alternative embodiment, the capillary tube 8 can be replaced by a calibrated orifice or by an expansion valve, in order to obtain the lamination of the refrigerant fluid.
[0033] According to one embodiment, the apparatus 1 comprises a four-way valve 9 connected with the compressor 2 and with the condenser 3, in order to put said compressor 2 in fluid communication with said condenser 3.
[0034] Preferably, the apparatus 1 comprises a liquid separator 10 connected with the four-way valve 9 and with the compressor 2. The liquid separator 10 is configured to separate the liquid portion of refrigerant fluid (e.g., drops of refrigerant fluid) from the gas portion of the refrigerant fluid. In other words, the liquid separator 10 allows only the gas portion of the refrigerant fluid to reach the compressor 2. The four-way valve 9 is connected with the evaporator 5 and with the liquid separator 10, in order to put the evaporator 5 in fluid communication with the liquid separator 10.
[0035] According to one embodiment, the condenser 3 comprises a finned pack heat exchanger 31 and a fan 32 configured for cooling the refrigerant fluid flowing through the finned pack heat exchanger 31.
[0036] For illustrative, yet incomplete purposes the apparatus 1 is configured to deliver a refrigerated fluid when operating a refrigeration cycle as described above (figures 1 and 2). In particular, the refrigerant fluid flows firstly through the compressor 2, secondly through the condenser 3, thirdly through the expansion valve 4 and through the branch 6 when the valve 7 is in the open configuration, and then through the evaporator 5.
[0037] According to one embodiment, the apparatus 1 comprises a command and control unit 11 to allow a user to set said valve 7 in the open configuration and in the closed configuration. For example, a user can choose the temperature of the refrigerated fluid to be delivered on the output pipe OUT setting the valve 7 in the closed configuration (e.g., lower temperature, -8°C<T<+4°C) and in the open configuration (e.g., higher temperature, +4°C<T<+12°C). Preferably, the command and control unit 11 is configured to operate electromechanical relays in order to set the valve 7 In the open configuration and in the closed configuration. More preferably, through the command and control unit 11 a user can close the electromechanical relay to set the valve 7 in the closed configuration (e.g., - 8°C<T<-5°C), and open the electromechanical relay to set the valve 7 in the open configuration (e.g., +7°C<T<+12°C).
[0038] According to one embodiment, the apparatus 1 comprises at least one sensor 12 configured for detecting a physical quantity in order to provide a corresponding output signal. The command and control unit 11 is in signal communication with at least one sensor 12 to receive and process the output signal, in order to monitor the apparatus 1.
[0039] Preferably, the sensor 12 comprises a pressure probe to detect a physical quantity in order to provide a corresponding output signal representative of the pressure of the refrigerant fluid inside the apparatus 1 (e.g., inside a pipe).
[0040] Preferably, the command and control unit 11 is connected with the compressor 2 to control the operation of the compressor 2 and the pressure of the refrigerant fluid inside the apparatus 1 in a specific position. For example, a sensor 12 can be located in the duct that connects the compressor 2 to the four-way valve 9 (as shown in figure 1).
[0041] According to one embodiment, the apparatus 1 is configured for delivering "warm" fluid on the output pipe (OUT) when the refrigeration cycle is inverted (i.e., when the flow of refrigerant fluid is inverted inside the pipes of the apparatus 1).
[0042] With reference to figure 3, the apparatus 1 comprises a first non-return valve 14 connected with the expansion vale 4, and with the evaporator 5. The first non-return valve is configured to allow the flow of refrigerant fluid only from the expansion valve 4 to the evaporator 5. In other words, when the refrigeration cycle is inverted to produce warm fluid, the refrigerant fluid cannot flow through the expansion valve 4 and through the branch 6.
[0043] Preferably, the apparatus 1 comprises a second branch 15 parallel to the series composed by the expansion valve 4 and the first non-return valve 14. The second branch 15 comprises a second non-return valve 16 connected with the condenser 3 and with an orifice 17. The second non-return valve 16 is configured to allow the flow of refrigerant fluid only from the orifice 17 to the evaporator 5. The orifice 17 is configured to laminate the refrigerant fluid when the refrigeration cycle is inverted (i.e., when the apparatus is set to produce warm fluid).
[0044] The second branch 15 also comprises an hydration filter 18 (e.g., calibrated filter) in fluid communication with the orifice 17, and configured to laminate the refrigerant fluid.
[0046] The four-way valve 9 is configured to change configuration to allow the inversion of the refrigeration cycle to produce warm fluid (e.g., warm water with a temperature ranging from 35°C to 60°C).
[0047] In other words, when the refrigeration cycle is inverted to produce warm fluid, the refrigerant fluid can flow through the second branch 15: firstly through the reservoir 19, secondly through the hydration filter 18, thirdly through the orifice 17, and then through the second non-return valve 16 (figure 3). When exiting the second branch 15, the refrigerant fluid flows firstly through the condenser 3, secondly through the compressor 2 and then through the evaporator 5.
1. An apparatus (1) for supplying refrigerated fluid, comprising:
- a compressor (2) configured for compressing a refrigerant fluid,
- a condenser (3) in fluid communication with said compressor (2) and configured for condensing said refrigerant fluid compressed by said compressor (2),
- an expansion valve (4) in fluid communication with said condenser (3) and configured for expanding said refrigerant fluid condensed by said condenser (3),
- an evaporator (5) comprising an inlet pipe (IN) and an outlet pipe (OUT) in fluid
communication with said inlet pipe (IN), said evaporator (5) is connected with said
expansion valve (4) to allow said refrigerant fluid expanded by said expansion valve
(4) to cool a fluid entering through said inlet pipe (IN) for delivering a refrigerated
fluid to said outlet pipe (OUT), said evaporator (5) is connected with said compressor
(2) to supply refrigerant fluid to said compressor (2),
characterised in that it comprises
- a branch (6) connected in parallel to said expansion valve (4), said branch (6)
comprises a valve (7) in fluid communication with said condenser (3) and a capillary
tube (8) in fluid communication with said valve (7),
and in that
- said valve (7) is configured to be set in an open configuration and in a closed configuration, said open configuration allows the flow of said refrigerant fluid through said capillary tube (8) to put said evaporator (5) in fluid communication with said capillary tube (8), said closed configuration prevents the flow of said refrigerant fluid through said capillary tube (8).
2. The apparatus (1) according to claim 1, wherein said expansion valve (4) comprises
a thermostatic valve.
3. The apparatus (1) according to claim 1 or 2, wherein said valve (7) comprises a solenoid
valve.
4. The apparatus (1) according to any one of the preceding claims, wherein it comprises:
- a four-way valve (9) connected with said compressor (2) and with said condenser (3) to put said compressor (2) in fluid communication with said condenser (3),
- a liquid separator (10) connected with said four-way valve (9) and with said compressor
(2), said liquid separator (10) is configured to separate a liquid portion of said
refrigerant fluid from a gas portion of said refrigerant fluid,
said four-way valve (9) is connected with said evaporator (5) and with said liquid
separator (10) to put said evaporator (5) in fluid communication with said liquid
separator (10).
5. The apparatus (1) according to any one of the preceding claims, wherein said condenser
(3) comprises a finned pack heat exchanger (31) and a fan (32) configured for cooling
said refrigerant fluid flowing through said finned pack heat exchanger (31).
6. The apparatus (1) according to any one of the preceding claims, wherein it comprises
a command and control unit (11) to allow a user to set said valve (7) in said open
configuration and in said closed configuration.
7. The apparatus (1) according to claim 6, wherein it comprises
- at least one sensor (12) configured for detecting a physical quantity in order to provide a corresponding output signal,
- said command and control unit (11) is in signal communication with said at least one sensor (12) to receive and process said output signal, in order to monitor said apparatus (1).