JP2004125310A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner capable of quickly restoring air conditioning operation when a heat source unit of a refrigerant circuit fails. <P>SOLUTION: The air conditioner has the heat source units 1a, 1b, and 1c, and one or a plurality of indoor units 2a, 2b, and 2c composing the refrigerant circuit along with the heat source units. It is provided with an auxiliary heat source unit 8, and switching means 4a, 4b, 4c, 5a, 5b, 5c, or 10a, 10b, and 10c capable of selectively switching between the heat source units and the auxiliary heat source unit and connecting them to the refrigerant circuit. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner, and more particularly to an air conditioner capable of recovering an air conditioning function early when a heat source device fails.
[0002]
[Prior art]
As is well known, a conventional air conditioner performs cooling and heating by forming a refrigerant circuit from a heat source unit and one or more indoor units connected to the heat source unit. In the case of a large size, a plurality of heat source units are often provided, and a plurality of refrigerant circuits are provided for each heat source unit. (For example, see Patent Document 1)
[0003]
[Patent Document 1]
JP-A-7-167519 (paragraph 0039, FIG. 3)
[0004]
[Problems to be solved by the invention]
In a conventional air conditioner, a heat source unit is provided with a compressor, a blower, and movable devices such as a flow path on-off valve, as well as devices such as a controller, necessary for operating a refrigeration cycle of a refrigerant circuit. However, in the unlikely event that any of these devices fails and becomes inoperable, the indoor unit connected to the failed refrigerant circuit will not be able to operate until the heat source unit is repaired. It becomes. In particular, when a component that directly contacts the refrigerant breaks down, it is necessary to collect the refrigerant once from the circuit, release the failure, and then re-enclose the refrigerant by evacuating the piping again, which takes a long time. There was a problem. The parts that are in direct contact with the refrigerant include a heat exchanger and a pressure sensor in addition to the movable parts.
On the other hand, depending on the application of the air conditioner, a situation in which the operation cannot be performed for a long time may not be tolerated, and it is an important problem how to quickly recover the air conditioning function when the heat source unit fails. Usually, a backup air conditioning system for backup is provided in case of failure, but in this case, a complete refrigerant circuit including a heat source unit and indoor units is provided as a spare, so double cost is required and economical There was a problem that the target burden became large.
[0005]
The present invention has been made in order to solve the above-described problems, and the fact that the above-described problem that requires a long time for recovery is often caused by a failure of a movable component such as a compressor. In view of the above, an object is to provide an economical air conditioner equipped with a standby heat source unit.
[0006]
[Means for Solving the Problems]
An air conditioner according to the present invention provides an air conditioner having a heat source unit and one or more indoor units that constitute a refrigerant circuit together with the heat source unit. There is provided switching means for selectively switching and connecting the heat source device and the standby heat source device.
[0007]
Further, in an air conditioner provided with a plurality of refrigerant circuits each having a heat source unit and one or a plurality of indoor units connected to the heat source unit, a spare heat source unit is provided, and a heat source unit of each of the refrigerant circuits is provided. And a spare heat source unit, and a switching means for connecting the spare heat source unit to any one of the heat source units of the refrigerant circuits.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a refrigerant circuit system diagram showing the configuration of the first embodiment. This figure shows an example in which three refrigerant circuits are juxtaposed to constitute an air conditioner. That is, the three heat source units 1a, 1b, 1c and the three indoor units 2a, 2b, 2c are connected by the refrigerant pipes 3a, 3b, 3c, respectively, to form a three-system refrigerant circuit. Specifically, a refrigerant circuit is constituted by a combination of the heat source unit 1a and the indoor unit 2a, a combination of the heat source unit 1b and the indoor unit 2b, and a combination of the heat source unit 1c and the indoor unit 2c. Normally, the refrigerant pipe connecting the heat source unit and the indoor unit is composed of a total of three lines, one each for the outward path and the return path from the heat source unit, or two for the outward path and one for the return path. In the drawings, these are indicated by a single line. On-off valves 4a, 4b, 4c are connected to the refrigerant pipes 3a, 3b, 3c, respectively, and branch pipes 6a, 6b, 6c are connected via other on-off valves 5a, 5b, 5c, respectively. A preliminary heat source device 8 is connected to the junction 7 of the pipe. Each of the on-off valves 4a, 4b, 4c and 5a, 5b, 5c is housed in a branch unit 9 as a switching means.
[0009]
In such a configuration, the on-off valves 4a, 4b, and 4c are open and the on-off valves 5a, 5b, and 5c are closed during normal operation, and the heat source unit 1a and the indoor unit 2a, the heat source unit 1b and the indoor unit 2b, The heat source unit 1c and the indoor unit 2c are respectively connected by refrigerant pipes 3a, 3b, and 3c, and air conditioning is performed for each refrigerant circuit. In this case, the preliminary heat source device 8 is separated from the refrigerant circuit. Here, if the heat source device 1a fails for some reason, the on-off valve 4a is closed and the on-off valve 5a is opened.
As a result, the preliminary heat source unit 8 is connected to the indoor unit 2a via the branch pipe 6a and the refrigerant pipe 3a to form a refrigerant circuit, and the heat source unit 1a is disconnected from the refrigerant circuit. That is, the spare heat source unit 8 is operated in place of the failed heat source unit 1a, and the air conditioning function of the refrigerant circuit including the indoor unit 2a is restored with only a short switching time. When the heat source unit 1b fails, the on-off valve 4b is closed and the on-off valve 5b is opened, and when the heat source unit 1c fails, the on-off valve 4c is closed and the on-off valve 5c is opened. Thereby, it can be switched and connected to the standby heat source device 8 in the same manner.
[0010]
In this way, by switching the refrigerant circuit using the on-off valve, even if a failure occurs in any of the heat source units 1a, 1b, and 1c, the air conditioning can be restored by the backup heat source unit 8. . In addition, since one emergency heat source unit can cope with a plurality of refrigerant circuit systems in case of emergency, a safe and economical air conditioner can be obtained. Although FIG. 1 shows an example in which the number of the refrigerant circuits is three, the number of the refrigerant circuits can be reduced to a larger number or a larger number.
[0011]
Embodiment 2 FIG.
Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a refrigerant circuit system diagram showing the configuration of the second embodiment. In this figure, the same or corresponding parts as those in FIG. The difference from FIG. 1 is that three-way valves 10 a, 10 b, and 10 c are provided as switching means in the branching unit 9, which can conduct flow paths in arbitrary two directions. In such a configuration, each of the three-way valves 10a, 10b, and 10c normally conducts the circuit of the heat source unit 1a and the indoor unit 2a, the circuit of the heat source unit 1b and the indoor unit 2b, and the circuit of the heat source unit 1c and the indoor unit 2c. If the heat source unit 1a fails, for example, the three-way valve 10a is switched so that the branch pipe 6a and the pipe 3a on the indoor unit 2a side conduct, so that the standby heat source unit 8 and the indoor unit 2a are connected. The circuit is turned on, the heat source unit is switched from 1a to the standby heat source unit 8, and the air conditioning function of the refrigerant circuit including the indoor unit 2a can be restored. The feature of this embodiment is that, in addition to the restoration of the air-conditioning function by switching to the standby heat source unit described above, when the standby heat source unit 8 switches to the standby heat source unit 8 and the standby heat source unit 8 further fails, the other two units Is that the backup operation by the heat source devices 1b and 1c can be performed.
[0012]
When the preliminary heat source unit 8 and the indoor unit 2a are in conduction, the three-way valve 10b conducts the circuit between the heat source unit 1b and the indoor unit 2b, and the three-way valve 10c conducts between the heat source unit 1c and the indoor unit 2c. Let me. If the standby heat source unit 8 fails in this state, the priority of the air-conditioning target of the indoor unit 2a and, for example, the priority of the air-conditioning target of the indoor unit 2b are checked, and if the air-conditioning target of the indoor unit 2a has a higher priority, Then, the flow path of the three-way valve 10b is switched to make the branch pipe 6b and the pipe 3b on the side of the heat source device 1b conductive. As a result, the heat source unit 1b is connected to the indoor unit 2a from the three-way valve 10b via the branch pipe 6b, the junction 7 and the branch pipe 6a, and restores the air conditioning operation of the indoor unit 2a.
As described above, by providing the three-way valve in each refrigerant circuit as a switching device, it is possible to perform the backup operation by the spare heat source device when the heat source device fails, and to perform other operations by the combination of the switching devices when the spare heat source device fails. The backup of the refrigerant circuit by the heat source device is also possible, and an air conditioning system excellent in safety and economy can be realized.
[0013]
Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a refrigerant circuit system diagram showing the configuration of the third embodiment. In this figure, the same or corresponding parts as those in FIG. The difference from FIG. 2 is that separate and independent branch units 9a, 9b, 9c are provided for each heat source unit, and these are individually installed in correspondence with the respective heat source units 1a, 1b, 1c. is there.
As described above, by separately installing the branch units 9a, 9b, and 9c, which are switching devices, for each heat source unit, it becomes easy to cope with the expansion of the refrigerant circuit system. That is, individual branch units 9a and the like are installed for each heat source unit of the added refrigerant circuit, and the branch pipes 6a and the like are connected to the junction 7 and connected to the standby heat source unit 8 to arbitrarily set up a backup standby unit. The heat source unit 8 can be used, and an air conditioning system with a higher degree of freedom can be designed.
[0014]
Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a control block diagram of an air conditioning system according to Embodiment 4 and corresponds to the refrigerant circuit system of FIG. That is, in FIG. 4, the controllers 11a, 11b, 11c are controllers mounted on the heat source units 1a, 1b, 1c, respectively, and the controllers 12a, 12b, 12c are mounted on the indoor units 2a, 2b, 2c, respectively. These are connected by transmission lines 13a, 13b, 13c. The controller 14 is a controller mounted on the branch unit 9, and controls the opening and closing operations of the on-off valves 4a, 4b, 4c, 5a, 5b, 5c. The controllers 11a, 11b, 11c and the controller 14 are connected by a transmission line 15.
[0015]
Next, a control algorithm according to this embodiment will be described with reference to the flowchart of FIG. The operation is started in step S1. At this time, there are three refrigerant circuits as shown in FIG. 1, but only one system of the heat source unit 1a will be described in the figure.
The same applies to other systems. The heat source units 1a, 1b, and 1c all have a maximum cooling capacity of, for example, a cooling capacity of 28 kW, the indoor units 2a, 2b, and 2c also have a cooling capacity of 28 kW, and the standby heat source unit 8 has a cooling capacity of 56 kW. We have ability.
In step S2, it is determined whether or not an abnormality that causes the heat source device 1a to become inoperable has occurred. If no abnormality has occurred, the process proceeds to step S3, and the operation is continued.
If an abnormality has occurred in the heat source unit 1a, the process proceeds to step S4, and the controller 11a transmits to the controller 14 a notification that the heat source unit 1a has entered an abnormal state in which the continuous operation cannot be performed.
[0016]
When the controller 14 receives the abnormal signal, the controller 14 issues a search request to the controller 11a for information on the configuration of the system in which the abnormality has occurred in step S5, here, information such as the number of indoor units 2a connected to the heat source unit 1a. . Then, in step S6, the presence of the abnormal system indoor unit (the presence of the controller 12a) is recognized. Next, in step S7, the indoor unit 2a is put into the operation suspension state. This is to prevent the operation signal of the indoor unit 2a from inducing a new trouble until the switching to the refrigerant circuit using the standby heat source unit 8 is completed while the heat source unit 1a is in an abnormal state. Next, the controller 14 checks the capacity of the indoor unit 2a as a refrigeration cycle in step S8.
The capacity referred to here is a size determined from the size of the heat exchanger, the amount of air blow, and the like. Since a numerical value indicating the capacity of the indoor unit 2a is set in the controller 12a, the indoor capacity is determined from the numerical value. Then, it is determined whether or not the room capacity is large enough to be covered by the backup heat source device 8.
[0017]
If only the heat source unit 1a fails, the capacity of the standby heat source unit 8 is 56 kW, which is larger than the capacity of the indoor unit 2a, 28 kW. When the process proceeds to step S10 due to the shortage of the capacity of the spare heat source device 8, it is a case where a plurality of heat source devices have failed and the total capacity of the failed heat source device exceeds the capacity of the spare heat source device 8. For this reason, the controller 14 stores the capacity of the indoor unit during backup, which is the capacity of the indoor unit of the failed system. The algorithm for this capacity determination is shown in the flowchart of FIG. ΣQj in step S18 is the total value of the capacity of the indoor unit operated by the backup heat source unit, and ΣQj0 in steps S17 and S18 is the total value of the indoor unit that has already been operated by the standby heat source unit because the other heat source unit has failed. The capacity, ΔQj, is the capacity of the indoor unit 2a of the heat source unit 1a that has recently failed. If it is determined in step S19 that the total capacity of the indoor units operated by the standby heat source unit is excessive, the operation of the indoor unit 2a is suspended in step S21 and the process proceeds to step S10 in FIG. In S20, the process proceeds to step S9 in FIG.
[0018]
If it is determined in step S8 in FIG. 5 that the capacity of the indoor unit 2a connected to the failed heat source unit 1a is small (the operation can be supplemented by the standby heat source unit 8), the process proceeds to step S9, and the system of the heat source unit 1a is connected. By closing the on-off valve 4a located and then opening the on-off valve 5a in step S11, the refrigerant circuit is switched between the indoor unit 2a and the standby heat source unit 8 to operate the indoor unit 2a. In step S12, the air conditioning in the indoor unit 2a is permitted, and the switching is completed in step S13.
As described above, even when an abnormality occurs in the heat source unit 1a and the operation becomes inoperable, automatic switching to the standby heat source unit 8 enables stable air conditioning to be continued, and highly reliable air conditioning can be achieved. It becomes possible to make a system.
Further, by making the capacity of the spare heat source unit 8 larger than the capacity of the other heat source units, even if the heat source unit of any of the refrigerant circuits fails, the necessary air conditioning capacity is not impaired. Even if the heat source unit in the circuit breaks down, if the actual air conditioning load is within the capacity of the spare heat source unit, one spare heat source unit can sufficiently cover the air conditioner, so that an air-conditioning system with excellent economy can be provided.
[0019]
In the flowchart of FIG. 5, the maximum capacity of the spare heat source unit 8 is compared with the indoor unit capacity of the system in which the abnormality has occurred in step S8. In such a case, it is also possible to proceed to step S9 in which the on-off valve is always opened without performing the capacity check in step S8. The flowchart in FIG. 7 shows this, and sets step S14 before step S8 to check whether or not there is a capacity limit. If the operation needs to be performed regardless of the capacity as described above, step S8 is executed. Is bypassed to advance to step S9.
The other steps are the same as those in FIG. The determination of the presence or absence of the capacity limitation in step S14 can be realized by providing the controller 14 with a function (such as switching by a switch) capable of setting the selection of the presence or absence of the capacity limitation in advance.
When switching to the standby heat source unit, the controller 11a transmits the abnormal state to the controller 14 by itself, but the controller 11a itself may fail and the abnormal state may not be transmitted to the controller 14.
In preparation for such a case, the controller 14 monitors the state of the controllers 11a, 11b, and 11c, and if the controller 11a, 11b, or 11c determines that the controller 11 is in an abnormal state, the controller 14 determines by itself. By having the function of switching to the standby heat source unit, the failure determination range can be expanded.
As a method of monitoring the states of the controllers 11a, 11b, and 11c, a signal for confirming whether the controller is normal or abnormal is periodically transmitted from the controller 14 to the controllers 11a, 11b, and 11c. And a method of determining whether there is a response from the controllers 11a, 11b, and 11c. Alternatively, the controller 11a, 11b, 11c monitors the transmission / reception state of the control information with the controllers 12a, 12b, 12c of the respective indoor units, thereby determining whether the controller 11a, 11b, 11c is normal or abnormal. Conceivable.
[0020]
【The invention's effect】
An air conditioner according to the present invention provides an air conditioner having a heat source unit and one or more indoor units that constitute a refrigerant circuit together with the heat source unit. Since the switching means for selectively switching and connecting the heat source device and the spare heat source device is provided, if a failure occurs in the heat source device, air conditioning can be restored by the spare heat source device.
[0021]
Further, in an air conditioner provided with a plurality of refrigerant circuits each having a heat source unit and one or a plurality of indoor units connected to the heat source unit, a spare heat source unit is provided, and a heat source unit of each of the refrigerant circuits is provided. And the spare heat source device is switched and connected, and the spare heat source device is provided with a switching means that can be connected in place of any one of the heat source devices of the respective refrigerant circuits. Even if a situation where the heat source unit becomes inoperable occurs, it is economical because a substitute heat source unit or a heat source unit of another refrigerant circuit can perform alternative operation.
[Brief description of the drawings]
FIG. 1 is a refrigerant circuit system diagram showing a configuration of a first embodiment of the present invention.
FIG. 2 is a refrigerant circuit system diagram showing a configuration of a second embodiment of the present invention.
FIG. 3 is a refrigerant circuit system diagram showing a configuration of a third embodiment of the present invention.
FIG. 4 is a control block diagram of an air conditioning system according to Embodiment 4 of the present invention.
FIG. 5 is a flowchart showing a control algorithm according to a fourth embodiment.
FIG. 6 is a flowchart illustrating an algorithm of capacity determination according to the fourth embodiment.
FIG. 7 is a flowchart showing a control algorithm when capacity confirmation is not performed in the fourth embodiment.
[Explanation of symbols]
1a, 1b, 1c heat source unit, 2a, 2b, 2c indoor unit,
3a, 3b, 3c piping, 4a, 4b, 4c on-off valve,
5a, 5b, 5c open / close valve, 8 preliminary heat source unit, 9 branch unit,
10a, 10b, 10c Three-way valve.

Claims (5)

In the air conditioner having a heat source unit and one or more indoor units constituting a refrigerant circuit together with the heat source unit, a spare heat source unit is provided, and the heat source unit and the spare heat source unit are provided for the refrigerant circuit. An air conditioner comprising a switching means capable of selectively switching connection. In an air conditioner having a plurality of refrigerant circuits each having a heat source unit and one or more indoor units connected to the heat source unit, a spare heat source unit is provided, and the heat source units of the refrigerant circuits and An air conditioner characterized by comprising switching means for switching and connecting a spare heat source device and connecting the spare heat source device to any one of the heat source devices of the refrigerant circuits. The switching means is provided for each refrigerant circuit, and is a three-way valve that is connected to the heat source unit and the indoor unit of the refrigerant circuit and the spare heat source unit and can conduct a flow path in any two directions. Item 3. The air conditioner according to Item 2. The maximum operable capacity of the spare heat source unit is set to be larger than the maximum capacity of the heat source units connected to the respective refrigerant circuits. Air conditioner. The air conditioner according to any one of claims 1 to 4, wherein the switching unit automatically switches to a standby heat source unit when an abnormal state of the heat source unit in the refrigerant circuit is detected.

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