JP4776511B2 - Refrigeration equipment - Google Patents

Description

  The present invention relates to a refrigeration apparatus that forms a refrigeration cycle.

  Refrigeration devices such as refrigerators and air conditioners form a refrigeration cycle by connecting compressors, condensers, expansion valves, evaporators, etc. with refrigerant piping, and use the phase change of refrigerant in the condenser or evaporator Thus, a load fluid such as air or water is heated or cooled.

  In such a refrigeration apparatus, it is necessary to control the amount of heat exchange between the refrigerant and the load fluid in the condenser or evaporator according to the degree of lightness of the load. It describes that the amount of heat exchange is controlled by controlling the compression capacity or the opening of the refrigerant flow valve.

JP-A-2005-345101

  However, as described in Patent Document 1, it may not be possible to flexibly cope with load fluctuations only by controlling the heat exchange amount by controlling the compression capacity of the compressor and the opening of the refrigerant flow valve.

  For example, in an air conditioner, if the room temperature is sufficiently cooled to the vicinity of the desired set temperature during cooling operation, the load will be reduced gradually. It may be too cool to cool below the set temperature. In order to avoid such overcooling, it is conceivable to perform ON / OFF control of the operation (compressor) of the air conditioner itself. However, uneven cooling of the load occurs with the operation ON / OFF. There may be a problem in reliability (lifetime) of components of an air conditioner such as a compressor.

  In addition, the refrigeration system that forms the refrigeration cycle not only fluctuates the load on the evaporator side (for example, the indoor temperature) but also varies independently on the condenser side (for example, the outdoor temperature). This makes it difficult to control the amount.

  This invention makes it a subject to implement | achieve the freezing apparatus which performs stably control of the heat exchange amount with respect to load fluctuation | variation.

In order to solve the above-described problems, the present invention provides an outdoor unit having an outdoor heat exchanger and an outdoor expansion valve, and an indoor unit having an indoor expansion valve, an indoor heat exchanger, a compressor, and a four-way valve. and by connecting a pipe for circulating a refrigerant to form a refrigeration cycle, it comprises a control means for controlling the heat exchange amount of the outdoor and indoor heat exchangers, heating or cooling load fluid by the outdoor or indoor heat exchanger In the remote condenser type refrigeration apparatus, the outdoor and indoor heat exchangers each have a plurality of distribution passages connected in parallel, and the outdoor and indoor expansion valves are provided in each of the plurality of distribution passages. The flow path is configured to be openable and closable, and the control means controls the opening and closing of the plurality of outdoor expansion valves based on the temperature of the load fluid of the outdoor heat exchanger, and based on the temperature of the load fluid of the indoor heat exchanger It controls the opening and closing of the plurality of the indoor expansion valve And wherein the door.

That is, the outdoor and indoor heat exchanger is formed by a plurality of distribution channels connected in parallel, since the expansion valve is provided for each of the distribution channels, any by opening and closing the expansion valve A number of distribution channels can be selected. Thereby, the heat transfer area of the outdoor and indoor heat exchangers can be controlled. By controlling the heat transfer area in the outdoor and indoor heat exchangers, the amount of heat exchange with the load fluid can be controlled. Therefore, the amount of heat exchange can be controlled by controlling the opening and closing of the expansion valve in response to load fluctuations. Can be performed stably.

  For example, if it is determined that the temperature of the indoor air that is the load fluid approaches the desired temperature and the load is light during the cooling of the air conditioner, the control means opens and closes the plurality of distribution flow paths that constitute the evaporator. By opening only a few of the open / close valves, and closing the remaining open / close valves, the operation can be continued with the amount of heat exchange in the evaporator being suppressed, thereby preventing overcooling and stopping the compressor. Can do.

By the way , in the refrigeration system forming the refrigeration cycle, not only the load fluctuation on the indoor heat exchanger side but also the load on the outdoor heat exchanger side fluctuates independently, so only by controlling the compression capacity or controlling the refrigerant flow rate It has been difficult to stably control the heat exchange amount. However, according to the first aspect of the refrigeration apparatus of the present invention , the control means controls the opening and closing of the plurality of outdoor expansion valves based on the temperature of the load fluid of the outdoor heat exchanger, and the load fluid of the indoor heat exchanger is controlled. Since the opening and closing of a plurality of indoor expansion valves is controlled based on the temperature, the load weight is determined based on the temperature of the load fluid on each of the outdoor side and the indoor side, and the opening and closing of each expansion valve is controlled. The heat transfer area can be controlled. Therefore, the heat exchange amount can be controlled by each heat exchanger for each load fluctuation on the outdoor side and the indoor side, and as a result, the control of the heat exchange amount with respect to the load fluctuation can be stably performed. it can.

  It is also possible to form an outdoor unit for each set of a plurality of distribution flow paths of the outdoor heat exchanger and an outdoor expansion valve corresponding to the flow paths. Thus, in the remote condenser type refrigeration apparatus, the degree of freedom in arrangement can be improved by dividing the outdoor unit into a plurality of units.

In addition, the present invention provides an outdoor unit, an indoor expansion valve, and an indoor heat exchanger that are formed by connecting a compressor, a four-way valve, an outdoor heat exchanger, and an outdoor expansion valve with a pipe for circulating refrigerant. Connected indoor units connected by piping that circulates refrigerant to form a refrigeration cycle, and includes control means for controlling the amount of heat exchange between the outdoor and indoor heat exchangers. In a separate refrigeration apparatus that heats or cools a fluid, the outdoor and indoor heat exchangers each have a plurality of distribution channels connected in parallel, and the outdoor and indoor expansion valves are provided in each of the distribution channels. Each flow path is configured to be openable and closable, and the control means controls the opening and closing of the plurality of outdoor expansion valves based on the temperature of the load fluid of the outdoor heat exchanger, and the temperature of the load fluid of the indoor heat exchanger Open and close the plurality of indoor expansion valves based on It may be configured to control.

  ADVANTAGE OF THE INVENTION According to this invention, the freezing apparatus which performs stably control of the heat exchange amount with respect to load fluctuation | variation is realizable.

  Hereinafter, an embodiment of a refrigeration apparatus to which the present invention is applied will be described with reference to FIGS. In the present embodiment, a remote condenser type air conditioner will be described as an example of a refrigeration apparatus. However, the present invention is not limited to this and can be applied to a separate type air conditioner. The present invention is not limited to an air conditioner, and can be applied to an apparatus formed with a refrigeration cycle such as a refrigerator used in a refrigeration showcase or a refrigerated warehouse. In the following description, the same functional parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a diagram showing an overall configuration of an air conditioner according to a first embodiment of the present invention. As shown in FIG. 1, an air conditioner 10 is configured by connecting an indoor unit 1 and an outdoor unit 2 with a pipe 3 that circulates a refrigerant.

  The indoor unit 1 is configured by connecting a compressor 4, a four-way valve 5, an indoor expansion valve 6, an indoor heat exchanger 7 and the like with a pipe 3 that circulates refrigerant, and the outdoor unit 2 includes outdoor heat. An exchanger 8 and an outdoor expansion valve 9 are connected by a pipe 3 that circulates a refrigerant. Thus, the air conditioner 10 is a remote condenser type air conditioner in which the compressor 4 is provided in the indoor unit 1.

  Next, the characteristic configuration of the present embodiment will be described. As shown in FIG. 1, the refrigerant pipe 3 inside the indoor unit 1 is composed of n distribution flow paths 3-1 to 3-n connected in parallel so that the circulating refrigerant is distributed in a plurality. . Indoor heat exchangers 7-1 to 7-n are formed in the distribution channels 3-1 to 3-n, respectively, and the indoor expansion is respectively performed in the flow channels 3-1 to 3-n. Valves 6-1 to 6-n are provided. Each of the indoor expansion valves 6-1 to 6-n can adjust the valve opening, and can control the opening and closing of the distribution flow paths 3-1 to 3-n.

  Similar to the indoor unit 1, inside the outdoor unit 2, the refrigerant pipe 3 is composed of n distribution channels 3-1 to 3-n that are connected in parallel so that the circulating refrigerant is distributed in a plurality. Yes. Outdoor heat exchangers 8-1 to 8-n are formed in the distribution channels 3-1 to 3-n, respectively, and outdoor expansion is performed in the flow channels 3-1 to 3-n, respectively. Valves 9-1 to 9-n are provided. The outdoor expansion valves 9-1 to 9-n each have an adjustable valve opening, and can control the opening and closing of the distribution channels 3-1 to 3-n. The outdoor unit 2 and the indoor unit 1 may have different numbers of flow paths.

  And the indoor unit 1 is provided with the control means 12 which is the characterizing part of a present Example. The control means 12 is connected to the indoor expansion valves 6-1 to 6-n and the outdoor expansion valves 9-1 to 9-n via control lines. Moreover, it connects with the indoor temperature detector 13 which detects the temperature of the room | chamber interior in which the indoor unit 1 was installed, and the outdoor temperature detector 14 which detects the outdoor temperature via a control line. The control means 12 may be provided in the indoor unit 1.

  Next, the control content of the control means 12 is demonstrated with the operation | movement of the air conditioner 10. FIG. The solid line arrows shown in FIG. 1 indicate the refrigerant flow during the cooling operation, and the broken line arrows indicate the refrigerant flow during the heating operation.

  First, during the cooling operation, the high-temperature and high-pressure refrigerant compressed by the compressor 4 passes through the four-way valve 5 and flows into the outdoor heat exchanger 8 and exchanges heat with the air passing through the outdoor heat exchanger 8. After being condensed and liquefied, it flows into the outdoor expansion valve 9. Here, among the outdoor heat exchangers 8-1 to 8-n, which heat exchanger the refrigerant flows into is controlled by the control means 12.

  The control means 12 compares the set temperature preset by the user or the like with the temperature obtained by the indoor temperature detector 13, determines the indoor load based on the difference Δt, and the outdoor expansion valve 9-1. Decide which of -9-n to open or close.

  That is, for example, when it is determined that the indoor temperature is relatively high with respect to the set temperature and the load is large, it is necessary to increase the amount of heat exchange and quickly bring it close to the set temperature. Heat is exchanged by opening all 9-n and allowing the refrigerant to flow through all of the outdoor heat exchangers 8-1 to 8-n.

  On the other hand, when the indoor temperature is cooled to a substantially set temperature and the load is small, only one of the outdoor expansion valves 9-1 to 9-n is opened and the outdoor heat exchange is opened. Heat is exchanged by allowing the refrigerant to flow only through the vessel 8.

  Further, the control means 12 controls the opening and closing of the outdoor expansion valve 9 based on the temperature of the outside air obtained by the outdoor temperature detector 14 in addition to the control by the indoor load based on the difference Δt. This is because, for example, the temperature of the outside air varies independently even when the indoor load is the same. Therefore, when the outside air is low and the condensation capacity is high, the number of outdoor expansion valves to be opened is reduced, and the outside air is highly condensed. If the capacity is low, increase the number of outdoor expansion valves to be opened.

  The refrigerant heat-exchanged with the outside air in the outdoor heat exchanger 8 corresponding to the outdoor expansion valve 9 opened by the control means 12 is sent to the indoor unit 1 through the outdoor expansion valve 9, and the indoor expansion valve 6 The pressure is reduced to a pressure at which the indoor heat exchanger 7 can evaporate, and then flows into the indoor heat exchanger 7 to exchange heat with the air passing through the indoor heat exchanger 7 to be evaporated and gasified.

  Here, the control means 12 compares the set temperature preset by the user or the like with the temperature obtained by the indoor temperature detector 13, determines the indoor load based on the difference Δt, and determines the indoor expansion valve. The expansion valve which performs pressure reduction is selected among 6-1 to 6-n. As a result, the refrigerant is depressurized by the selected indoor expansion valve 6 and is evaporated by exchanging heat only by the indoor heat exchanger 7 corresponding to the expansion valve. The gas refrigerant evaporated by heat exchange in the indoor heat exchanger 7 returns to the compressor 4 through the four-way valve 5 again.

  In the case of heating operation, the basic operation is the same as that during cooling only by switching the four-way valve 5 and reversing the refrigerant circulation direction. That is, the refrigerant compressed by the compressor 4 flows into the indoor heat exchanger 7 through the four-way valve 5 as indicated by the broken line arrow, and heat-exchanges with the air passing through the indoor heat exchanger 7 to be condensed and liquefied. Thereafter, the pressure is reduced by the outdoor expansion valve 9, the heat is exchanged by the outdoor heat exchanger 8, and evaporated to return to the compressor 4 as a gas refrigerant.

  The control means 12 compares the set temperature preset by the user and the room temperature obtained by the room temperature detector 13 with respect to the control of the indoor expansion valves 6-1 to 6-n. The indoor load is determined based on Δt, and which of the indoor expansion valves 6-1 to 6-n is to be opened or closed is selected. When the load is large, many indoor expansion valves are opened to increase the heat exchange amount, and when the load is small, the number of indoor expansion valves to be opened is decreased to suppress the heat exchange amount.

  Regarding the control of the outdoor expansion valves 9-1 to 9-n, the pressure is reduced in the outdoor expansion valves 9-1 to 9-n according to the indoor load based on the difference Δt and the outdoor load based on the outdoor temperature. The expansion valve that performs the control is selected, and the amount of heat exchange in the outdoor heat exchanger 8 is controlled.

  Next, the arrangement of the indoor heat exchanger 7 and the outdoor heat exchanger 8 will be described with reference to FIG. FIG. 2 shows an example in which the heat exchangers divided into n are vertically arranged at equal intervals. The divided heat exchangers may be arranged at equal intervals in the vertical direction in this way, or may be arranged at equal intervals in the left-right or depth direction. Moreover, you may arrange | position at intervals rather than equal intervals.

  And the heat exchanger selected by the control means 12 may be, for example, heat exchangers selected one by one from the first, or odd numbers such as first, third, fifth, etc. You may choose the number. An even number may be selected. That is, among the n heat exchangers, the number of heat exchangers to be opened or closed is controlled based on the indoor temperature or the outdoor temperature as described above, and the location of the heat exchanger to be opened or closed The combination can be selected as appropriate.

  As described above, according to the present embodiment, the outdoor heat exchanger 8 and the indoor heat exchanger 7 each have a heat exchanger formed by a plurality of distribution channels 3-1 to 3-n. Each of the distribution channels can be controlled to open and close by the outdoor expansion valve 9 and the indoor expansion valve 6. Therefore, the heat exchange area of the outdoor heat exchanger 8 and the indoor heat exchanger 7 can be controlled to control the heat exchange amount, and as a result, the heat exchange amount with respect to load fluctuation can be stably controlled. .

  In addition, the heat transfer area can be controlled by controlling the opening and closing of the outdoor expansion valve in consideration of not only the load based on the difference between the indoor temperature and the set temperature but also the load on the outdoor heat exchanger based on the outdoor temperature. . Therefore, the heat exchange amount can be controlled by each heat exchanger for each load fluctuation on the outdoor side and the indoor side, and as a result, the control of the heat exchange amount with respect to the load fluctuation can be stably performed. it can.

  FIG. 3 is a diagram showing an overall configuration of an air conditioner according to a second embodiment of the present invention. The present embodiment differs from the first embodiment in that each of the outdoor heat exchangers 8-1 to 8-n and the outdoor expansion valve 9-1 to 9-n corresponding to each of the outdoor heat exchangers 8-1 to 8-n It is only a point where −1 to 2-n are formed. Since other parts are the same as those in the first embodiment, description thereof is omitted.

  Thus, the freedom degree of the installation place of an outdoor unit improves by forming an outdoor unit for every group of a heat exchanger and an expansion valve. In particular, in a remote condenser type air conditioner, for example, there are many cases where the installation location is restricted with respect to, for example, the size and weight of an outdoor unit, and in this case, this embodiment is suitable.

  In the above-described embodiment, an air conditioner capable of both cooling and heating using a four-way valve has been described as an example. However, the present invention is not limited thereto, and the present invention can only cool without using a four-way valve. It can be applied to a refrigerator. In this case, the valve provided on the condenser side is not an expansion valve that can adjust the opening degree of the valve, but may be a valve that can only perform opening / closing control such as an electromagnetic valve.

  In addition to controlling the heat exchange amount of the outdoor heat exchanger or the indoor heat exchanger based on the outside air or the indoor temperature as in the embodiment, the operation is performed in conjunction with the capacity control of the compressor and the adjustment by the decompression device. By doing so, it is possible to deal with a wider range of heat capacity balance and stably control the amount of heat exchange with respect to load fluctuations.

  Furthermore, the present invention is applicable to a separate type air conditioner in which a compressor is provided in an outdoor unit, and a so-called multi-type air conditioner in which a plurality of indoor units are connected to one outdoor unit. It is also applicable to. In such an air conditioner, since operation ON / OFF occurs in each indoor unit, the heat exchange amount in the outdoor heat exchanger is balanced with the total heat exchange amount of the indoor heat exchanger of the operating indoor unit. It is necessary and will change from time to time. In the case of such a sudden change in load, there are cases in which it is not possible to flexibly cope with load fluctuations only by conventional compressor capacity control or refrigerant flow valve opening degree control. By applying this, the heat exchange amount can be controlled more finely and stably.

  In the embodiment, the outdoor expansion valve and the indoor expansion valve are controlled based on the outdoor temperature and the indoor temperature. However, the present invention is not limited to this, and various control factors can be added. For example, in an air conditioner equipped with an energy saving mode, when the user selects the energy saving mode, the expansion valve is controlled to improve energy efficiency at the expense of some time until the room temperature reaches the set temperature. It is also possible to do.

It is a figure which shows the whole structure of the air conditioner of 1st Example of this invention. It is a figure which shows the example of arrangement | positioning of a heat exchanger. It is a figure which shows the whole structure of the air conditioner of 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Indoor unit 2 Outdoor unit 3 Piping 4 Compressor 5 Four-way valve 6 Indoor expansion valve 7 Indoor heat exchanger 8 Outdoor heat exchanger 9 Outdoor expansion valve 10 Air conditioner 12 Control means 13 Indoor temperature detector 14 Outdoor temperature detector

Claims (3)

An outdoor unit having an outdoor heat exchanger and an outdoor expansion valve, and an indoor expansion valve, an indoor heat exchanger, a compressor, and an indoor unit having a four-way valve are connected to each other through a pipe for circulating a refrigerant to be frozen. In a remote condenser type refrigeration apparatus that forms a cycle and includes control means for controlling the heat exchange amount of the outdoor and indoor heat exchangers, and heats or cools the load fluid by the outdoor or indoor heat exchangers,
The outdoor and indoor heat exchangers each have a plurality of distribution channels connected in parallel,
The outdoor and indoor expansion valves are provided in each of the plurality of distribution flow paths, and are formed so that each flow path can be opened and closed.
The control means controls opening and closing of the plurality of outdoor expansion valves based on the temperature of the load fluid of the outdoor heat exchanger, and controls the plurality of indoor expansion valves based on the temperature of the load fluid of the indoor heat exchanger. A refrigeration apparatus that controls opening and closing . The refrigeration apparatus according to claim 1 , wherein an outdoor unit is formed for each set of a plurality of distribution flow paths of the outdoor heat exchanger and an outdoor expansion valve corresponding to the flow paths. Refrigeration equipment. An outdoor unit in which a compressor, a four-way valve, an outdoor heat exchanger, and an outdoor expansion valve are connected by a pipe for circulating the refrigerant, and a pipe for circulating the refrigerant between the indoor expansion valve and the indoor heat exchanger. Connecting indoor units connected to form a refrigeration cycle, comprising control means for controlling the heat exchange amount of the outdoor and indoor heat exchangers, and heating the load fluid by the outdoor or indoor heat exchangers In a separate type refrigeration apparatus for cooling,
The outdoor and indoor heat exchangers each have a plurality of distribution channels connected in parallel,
The outdoor and indoor expansion valves are provided in each of the distribution flow paths, and are formed so that each flow path can be opened and closed.
The control means controls opening and closing of the plurality of outdoor expansion valves based on the temperature of the load fluid of the outdoor heat exchanger, and controls the plurality of indoor expansion valves based on the temperature of the load fluid of the indoor heat exchanger. Refrigeration apparatus characterized by controlling opening and closing

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