JP7402025B2 - air conditioning system - Google Patents

Description

The present invention relates to an air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space.

In the above air conditioning system, there is a possibility that the coil may freeze due to a decrease in the temperature of the outside air. Therefore, conventionally, systems having a configuration for preventing freezing of the coil have been proposed (see, for example, Patent Documents 1 and 2).

In the systems described in Patent Documents 1 and 2, indoor air from an indoor space is supplied to an outside air intake duct, etc., and the indoor air is mixed with outside air to increase the temperature of outside air, and the temperature of the outside air with the increased temperature is increased. is supplied to the coil to prevent it from freezing. As a result, instead of newly generating air or the like to prevent the coil from freezing, the indoor air, which is higher in temperature than the outside air, is used to prevent the coil from freezing.

Utility model registration No. 2527660 Utility Model Publication No. 3-100723

However, in the systems described in Patent Documents 1 and 2, indoor air is mixed with outdoor air, so the temperature of the air supplied to the coil is lower than that of indoor air. Therefore, although indoor air is used, indoor air whose temperature has been lowered is supplied to the coil, making it difficult to efficiently prevent the coil from freezing.

In view of this situation, the main object of the present invention is to provide an air conditioning system that can efficiently prevent freezing of coils.

A first characteristic configuration of the present invention is an air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space.
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air ,
The coil installation space is provided in the casing of the air conditioner in a state where it is divided by a partition body,
The indoor air supply section is provided with an indoor air return path that is connected to the coil installation space in addition to an outside air intake section that takes outside air into the air conditioner, and the indoor air return path supplies air to the coil installation space. The point is that it supplies indoor air to the indoor space .

According to this configuration, the indoor air supply unit supplies indoor air to the coil installation space without mixing it with outside air, so the coil installation space can be warmed while using the heat of the indoor air as it is, and the coil installation space can be heated using the heat of the indoor air. Freezing prevention can be performed efficiently. Moreover, since the coil installation space is separated from the outside air and not communicated with it, the coil can be efficiently heated by the indoor air supplied by the indoor air supply section.

A second characteristic configuration of the present invention is an air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space.
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air,
The air conditioner includes air that can be freely switched between a communication state in which a communication space is formed between the coil installation space and the outside air and a non-communication state in which an air layer is separated from the outside air and is not communicated. A layer forming space is provided ,
The air layer forming space is separated from the coil installation space by a partition and is a filter installation space in which a filter is installed,
The partition body is provided with a communication state switching unit that can switch freely between a communication state in which the filter installation space and the coil installation space are communicated and a non-communication state in which the filter installation space and the coil installation space are not communicated. The point is that

According to this configuration, the indoor air supply unit supplies indoor air to the coil installation space without mixing it with outside air, so the coil installation space can be warmed while using the heat of the indoor air as it is, and the coil installation space can be heated using the heat of the indoor air. Freezing prevention can be performed efficiently. Moreover, since the coil installation space is separated from the outside air and not communicated with it, the coil can be efficiently heated by the indoor air supplied by the indoor air supply section.
Furthermore, according to this configuration, by switching the air layer forming space to a non-communicating state, an air layer separated from the outside air can be formed between the coil installation space and the outside air. Therefore, this air layer can function as a heat insulating layer for the coil installation space against outside air, and the coil can be prevented from freezing even more efficiently.

A third characteristic configuration of the present invention is an air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space.
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air,
an outside air intake unit that takes outside air into the air conditioner;
In a state in which communication between the outside air and the air conditioner in the outside air intake section is cut off, indoor air from the indoor space is made to flow through the outside air intake section in a direction opposite to the flow direction from the outside air side to the air conditioner side. The present invention is provided with a backflow indoor air circulation section.

According to this configuration, the indoor air supply unit supplies indoor air to the coil installation space without mixing it with outside air, so the coil installation space can be warmed while using the heat of the indoor air as it is, and the coil installation space can be heated using the heat of the indoor air. Freezing prevention can be performed efficiently. Moreover, since the coil installation space is separated from the outside air and not communicated with it, the coil can be efficiently heated by the indoor air supplied by the indoor air supply section.
Furthermore, according to this configuration, the backflow indoor air flow section allows indoor air to flow through the outside air intake section in the opposite direction to the flow direction from the outside air side to the air conditioner side, so that only the coil installation space is Instead, the outside air intake can also be heated with indoor air. Therefore, it is possible to prevent low-temperature outside air from being taken in by the outside air intake section, and it is possible to more appropriately prevent the coil from freezing.

A fourth characteristic configuration of the present invention is an air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space.
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air,
An operation control unit that controls the operating state of the air conditioner and the indoor air supply unit is provided,
The operation control unit operates a first anti-freeze operation in which the indoor air supply unit is operated to supply indoor air to the coil installation space as an anti-freeze operation to prevent freezing of the coil, and a first anti-freeze operation in which indoor air is supplied to the coil installation space. and a second anti-freeze operation in which a heat medium is circulated and supplied to the coil,
The operation control unit performs the first anti-freezing operation when a first anti-freezing condition is satisfied, and when the temperature of the coil installation space becomes equal to or lower than a set temperature during execution of the first anti-freezing operation, the operation control unit performs the first anti-freezing operation. The second antifreeze operation is performed.

According to this configuration, the indoor air supply unit supplies indoor air to the coil installation space without mixing it with outside air, so the coil installation space can be warmed while using the heat of the indoor air as it is, and the coil installation space can be heated using the heat of the indoor air. Freezing prevention can be performed efficiently. Moreover, since the coil installation space is separated from the outside air and not communicated with it, the coil can be efficiently heated by the indoor air supplied by the indoor air supply section.
Furthermore, according to this configuration, the operation control unit first performs the first anti-freezing operation when the first anti-freezing condition is satisfied, so that the coil is prevented from freezing without operating the air conditioner. be able to. Therefore, even if the air conditioner is not operating, the coil can be properly prevented from freezing, and energy can be saved. Moreover, even if the operation control unit performs the first anti-freeze operation, if the temperature of the coil installation space falls below the set temperature, the operation control unit performs the second anti-freeze operation. , it is possible to prevent the coil from freezing, and it is possible to reliably prevent the coil from freezing.
A fifth characteristic configuration of the present invention is that the indoor air supply unit is provided with an indoor air circulation unit that circulates indoor air between the indoor space and the coil installation space, separately from the air conditioner, and the air conditioner The indoor air circulation section is configured to be operable even when the operation of the indoor air circulation section is stopped.
According to this configuration, the indoor air circulation unit is provided separately from the air conditioner, and circulates indoor air between the indoor space and the coil installation space regardless of whether the air conditioner is operating or not. can be done. As a result, even if the air conditioner is not operating at night, when the coil is likely to freeze, the indoor air circulation unit can be activated to warm the coil with indoor air and prevent the coil from freezing. I can do it. Moreover, since the indoor air circulation unit is only operated without operating the air conditioner, it is possible to prevent the coil from freezing at an appropriate timing while saving energy.

Diagram showing the operating status of air conditioning operation in the schematic configuration of the air conditioning system Diagram showing the operating state of the first antifreeze operation in the schematic configuration of the air conditioning system Flowchart showing operations during antifreeze operation A diagram showing the operating state of the first antifreeze operation in the schematic configuration of the air conditioning system in the second embodiment A diagram showing the operating state of the first antifreeze operation in the schematic configuration of the air conditioning system in the third embodiment A diagram showing the operating state of the first antifreeze operation in the schematic configuration of the air conditioning system in the fourth embodiment A diagram showing the operating state of the first antifreeze operation in the schematic configuration of the air conditioning system in the fifth embodiment A diagram showing the open and closed states of the first to fifth communication state switching parts in the air conditioner according to the fifth embodiment

Embodiments of an air conditioning system according to the present invention will be described based on the drawings.
[First embodiment]
As shown in FIG. 1, this air conditioning system 100 includes an air conditioner 1 that conditions outside air OA using a coil 11 and supplies the air SA after the air conditioning process to an indoor space 2. The air conditioner 1 includes an air filter 12, a coil 11, and a fan 13 in this order from the upstream side in the air flow direction. The air conditioner 1 includes a circulation supply path 14 that circulates and supplies a heat medium (cold water or hot water) from an external heat source to the coil 11, and a supply state that supplies the heat medium to the coil 11 and a supply that stops the supply of the heat medium. A flow rate adjustment valve 15 is provided that can be switched to a stop state and can freely adjust the flow rate of the heat medium in a supply state.

Here, FIG. 1 and FIG. 2 show the same schematic configuration of an air conditioning system 100, but differ in the air flow state, the operating state of the equipment, the opening/closing state of the damper, and the like. In FIGS. 1 and 2, devices in the operating state are shown in thick lines, and open/closeable members such as the communication state switching unit 20 and the first to fourth dampers D1 to D4 are shown in outline. , the closed state is shown in black. Further, although FIGS. 4 to 8 show schematic configurations of other embodiments of the air conditioning system 100 and the air conditioner 1, FIGS. 4 to 8 also show the equipment in the operating state, as in FIGS. are shown in thick lines, and for openable and closable members, those in the open state are shown in white, and those in the closed state are shown in black.

The casing of the air conditioner 1 includes, in order from the upstream side in the air flow direction, a filter installation space 16 in which the air filter 12 is installed, a coil installation space 17 in which the coil 11 is installed, and a fan installation space 18 in which the fan 13 is installed. It is equipped. The filter installation space 16 and the coil installation space 17 are separated and shielded (not communicated) by a partition body 19, whereas the coil installation space 17 and the fan installation space 18 are partitioned. It is provided in an open state (communicated state) without being closed. The partition body 19 can be freely switched between a communication state (open state) in which the filter installation space 16 and the coil installation space 17 are communicated, and a non-communication state (closed state) in which the filter installation space 16 and the coil installation space 17 are not communicated. A communication state switching section 20 (damper) is provided.

The air conditioning system 100 includes an outside air intake path 4 (corresponding to an outside air intake section) that guides outside air OA introduced from the outside air louver 3 to the air conditioner 1, and an outside air intake passage 4 (corresponding to an outside air intake section) that supplies conditioned air SA from the air conditioner 1 to the indoor space 2. an air supply path 5 that guides the indoor air EA in the indoor space 2 to the exhaust louver 6 and exhausts it to the outside; A return path 8 and a second return path 9 (corresponding to an indoor air return path) for returning indoor air EA in the indoor space 2 to the coil installation space 17 of the air conditioner 1 are provided.

The outside air intake passage 4 is provided in a state that allows the outside air louver 3 and the filter installation space 16 of the air conditioner 1 to communicate with each other. In the outside air intake path 4 , on the downstream side in the air flow direction from the connection point with the first return path 8 , there are two states: a supply state (open state) for supplying outside air OA to the air conditioner 1 and a state for supplying outside air OA to the air conditioner 1 . A first damper D1 is provided that can be switched to a supply stop state (closed state) in which the supply of outside air OA is stopped. The air supply path 5 is provided to communicate the fan installation space 18 of the air conditioner 1 and the indoor space 2.

The exhaust passage 7 is provided to communicate the indoor space 2 and the exhaust louver 6. The exhaust path 7 includes an air supply fan 10 that allows the indoor air EA of the indoor space 2 to flow through it, and an exhaust state (open state) that exhausts the air of the indoor space 2 from the exhaust louver 6 and a state where the exhaust from the exhaust louver 6 is stopped. A second damper D2 is provided that can be freely switched between an exhaust stop state (closed state) and an exhaust stop state (closed state). As a result, the exhaust path 7 includes, in order from the upstream side in the air flow direction, the air supply fan 10, the connection point with the second return path 9, the connection point with the first return path 8, and the second damper D2. It is equipped.

The first return path 8 is branched from a midway point of the exhaust path 7 and is connected to join a midway point of the outside air intake path 4 . A third damper is provided in the first return path 8 and is switchable between a flow state (open state) in which air flows through the first return path 8 and a flow stop state (closed state) in which air flow is stopped. D3 is provided. The second return path 9 is branched from the middle of the exhaust path 7 and is connected to the coil installation space 17 of the air conditioner 1 . A fourth damper is provided in the second return path 9 and is switchable between a flow state (open state) in which air flows through the second return path 9 and a flow stop state (closed state) in which air flow is stopped. D4 is provided.

The air conditioning system 100 includes an operation control unit that controls the operation of the air conditioning system 100 by controlling the operating states of the air conditioner 1, the air supply fan 10, the communication state switching unit 20, and the first to fourth dampers D1 to D4. 101 is provided. The operation control unit 101 is capable of executing a cooling operation for cooling the indoor space 2 and a heating operation for heating the indoor space 2 as air conditioning operations, and in addition to the air conditioning operation, an antifreeze operation for preventing the coil 11 from freezing. It is configured to be able to execute various operations such as driving. Each operation will be explained below.

(Cooling operation)
In the cooling operation, as shown in FIG. 1, the operation control unit 101 puts the air conditioner 1 into the cooling operation state, puts the air supply fan 10 into the operating state, switches the communication state switching part 20 to the communication state (open state), The first and second dampers D1 and D2 are switched to the open state, and the third and fourth dampers D3 and D4 are set to the closed state. In the cooling operation state, the air conditioner 1 operates the fan 13, opens the flow rate adjustment valve 15, and circulates and supplies a cooling heat medium (for example, cold water) to the coil 11 through the circulation supply path 14. The flowing air can be cooled by the coil 11.

In the cooling operation, as shown by the arrow in FIG. 1, outside air OA is taken into the filter installation space 16 of the air conditioner 1 through the outside air intake passage 4, and is purified by passing through the air filter 12. The outside air OA taken into the filter installation space 16 is supplied to the coil installation space 17 through the communication state switching section 20 and is cooled by the coil 11 . The cooled air SA is supplied to the indoor space 2 through the fan installation space 18 and the air supply path 5, thereby cooling the indoor space 2. Indoor air EA in the indoor space 2 is exhausted to the outside through an exhaust path 7.

In the cooling operation, the operation control unit 101 controls the flow rate in the air conditioner 1 based on the detection information of the first temperature detection unit T1 that detects the indoor temperature of the indoor space 2 so that the detected indoor temperature becomes the set temperature. The opening degree of the regulating valve 15, the rotation speed of the fan 13, etc. are controlled. The temperature setting can be set by the user using, for example, a remote control.

(Heating operation)
In the heating operation, as shown in FIG. 1, the operation control unit 101 puts the air conditioner 1 into the heating operation state, puts the air supply fan 10 into the operating state, switches the communication state switching part 20 to the communication state (open state), The first and second dampers D1 and D2 are switched to the open state, and the third and fourth dampers D3 and D4 are set to the closed state. Since the air flow condition is the same in the cooling operation and the heating operation, it will be explained using FIG. 1.

The heating operation state of the air conditioner 1 differs from the cooling operation state only in that the heat medium supplied to the coil 11 is a heating heat medium (for example, hot water), and the rest is the same. Detailed explanation will be omitted.

In the heating operation, as shown by the arrow in FIG. 1, outside air OA is taken into the filter installation space 16 of the air conditioner 1 through the outside air intake passage 4, and is purified by passing through the air filter 12. The outside air OA taken into the filter installation space 16 is supplied to the coil installation space 17 through the communication state switching section 20 and is heated in the coil 11 . The heat-treated air SA is supplied to the indoor space 2 through the fan installation space 18 and the air supply path 5, and heats the indoor space 2. Indoor air EA in the indoor space 2 is exhausted to the outside through an exhaust path 7.

(Anti-freezing operation)
The operation control unit 101 is configured to be able to execute a first antifreeze operation in which indoor air EA is supplied to the coil installation space 17 and a second antifreeze operation in which a heat medium is circulated to the coil 11 as the antifreeze operation. ing.

(First antifreeze operation)
In the first antifreeze operation, as shown in FIG. the third and fourth dampers D3 and D4 are switched to the open state, and the first and second dampers D1 and D2 are set to the closed state. In the first antifreeze operation, the air conditioner 1 is kept stopped, so even if the air conditioner 1 is stopped, the coil 11 is prevented from freezing without having to restart the air conditioner 1. be able to.

In the first anti-freeze operation, as shown by the arrow in FIG. It is supplied to the coil installation space 17. The indoor air EA supplied to the coil installation space 17 is returned to the indoor space 2 through the fan installation space 18 and the air supply path 5 because the communication state switching unit 20 is in the non-communication state. In this way, by circulating and supplying the indoor air EA, which has a higher temperature than the outside air OA, to the coil installation space 17 without mixing it with the outside air OA, the coil 11 is warmed by using the heat of the indoor air EA. Therefore, the coil 11 can be prevented from freezing.

The indoor air supply section 21 can be composed of an air supply fan 10, an exhaust path 7, a second return path 9, first to fourth dampers D1 to D4, and the like. A separately operable indoor air circulation section 22 can be composed of an air supply fan 10, an exhaust path 7, a second return path 9, a fourth damper D4, and the like. Since the exhaust passage 7 and the air supply fan 10 are originally provided for performing cooling operation and heating operation, the second return passage 9 and the first to fourth dampers D1 to D4 are used to perform the first antifreeze operation. Just add .

Moreover, since the first damper D1 is in the closed state and the communication state switching section 20 is in the non-communication state, the filter installation space 16 can be made into an air layer that is separated from the outside air OA and not communicated with it. This allows the filter installation space 16 (corresponding to the air layer formation space) to be an air layer to exist between the outside air OA and the coil installation space 17. It functions as a heat insulating layer for the installation space 17 and prevents the cold heat of the outside air OA from being transferred to the coil installation space 17, thereby making it possible to more effectively prevent the coil 11 from freezing.

By operating the air supply fan 10, the indoor air EA of the indoor space 2 is supplied not only to the coil installation space 17 but also to the outside air intake passage 4. As shown by the arrow in FIG. 2, the operation of the air supply fan 10 causes the indoor air EA in the indoor space 2 to flow through the exhaust passage 7, so that it passes through the first return passage 8 and into the outside air intake passage 4. is supplied to. Since the first damper D1 is in the closed state, the communication between the outside air OA in the outside air intake path 4 and the air conditioner 1 is cut off, and the air flows from the outside air OA side to the air conditioner 1 side in the outside air intake path 4. This is to prevent any flow from occurring. In this state, by allowing the indoor air EA to flow through the outside air intake path 4 through the first return path 8, the flow direction is opposite to the direction of flow from the outside air OA side to the air conditioner 1 side through the outside air intake path 4. By passing the indoor air EA through the room, the outside air intake passage 4 can also be warmed by the indoor air EA.

In this way, the backflow indoor air circulation section 23 is composed of the air supply fan 10, the first return path 8, the first and third dampers D1, D3, etc., and is located on the outside air OA side with respect to the outside air intake path 4. The indoor air EA is made to flow in a direction opposite to the direction of flow from the air conditioner 1 to the air conditioner 1 side.

(Second antifreeze operation)
To explain with reference to FIG. 1, in the second antifreeze operation, the operation control unit 101 operates the air conditioner 1, opens the flow rate adjustment valve 15 of the circulation supply path 14, and sets the heat medium (for example, hot water ) is circulated and supplied to the coil 11. At this time, the flow rate of the heat medium that is circulated and supplied to the coil 11 can be set to, for example, the minimum flow rate.

The operation in the antifreeze operation will be explained based on the flowchart in FIG. 3.
While the air conditioner 1 is not operating, the operation control unit 101 performs temperature measurement processing (step #1). In the temperature measurement process, the operation control unit 101 switches the third and fourth dampers D3 and D4 to the open state, closes the first and second dampers D1 and D2, and switches the first to third temperature detection units T1 to The temperature is detected at each of T3. The first temperature detection section T1 detects the indoor temperature t1 of the indoor space 2, the second temperature detection section T2 detects the outside air temperature t2 in the outdoor air intake passage 4, and the third temperature detection section T3 detects the temperature t3 of the coil installation space 17. Temperature detection by each of the first to third temperature detection units T1 to T3 is repeatedly performed at a predetermined period or in real time.

If the outside air temperature t2 of the second temperature detection unit T2 is equal to or lower than the first set temperature (for example, 5°C), the operation control unit 101 operates the air supply fan 10, assuming that the first antifreeze condition is satisfied. and performs the first antifreeze operation (if Yes in step #2, step #3).

If the temperature t3 of the coil installation space 17 of the third temperature detection unit T3 is equal to or lower than the indoor temperature t1 of the first temperature detection unit T1, the operation control unit 101 causes the first antifreeze operation to continue (Yes in step #4). in the case of). As a result, the first antifreeze operation is performed so that the temperature t3 of the coil installation space 17 becomes equal to the indoor temperature t1 of the first temperature detection part T1, and the heat possessed by the indoor air EA is utilized to the maximum. Thus, the coil installation space 17 can be heated.

When the temperature t3 of the coil installation space 17 of the third temperature detection section T3 becomes higher than the indoor temperature t1 of the first temperature detection section T1 during execution of the first antifreeze operation, the operation control section 101 controls the third and third temperature detection sections T3. 4, the dampers D3 and D4 are closed, the air supply fan 10 is stopped, and the supply of the indoor air EA to the coil installation space 17 and the supply of the indoor air EA to the outside air intake passage 4 is stopped. 1. The antifreeze operation is stopped (if No in step #4, step #5).

Even if the first anti-freezing operation is performed, if the temperature t3 of the coil installation space 17 of the third temperature detecting section T3 is below the second set temperature (for example, 3 degrees Celsius), the operation control section 101 will cause the second anti-freezing operation to occur. Preventive operation is performed (if Yes in step #6, step #7). In this way, even if the first antifreeze operation is performed, if the temperature t3 of the coil installation space 17 of the third temperature detection section T3 is lower than the second set temperature (for example, 3° C.), the first antifreeze operation is performed. Assuming that the freezing of the coil 11 cannot be prevented by this alone, a second anti-freezing operation can be performed.

During execution of the second antifreeze operation, the operation control unit 101 performs the second freezing operation until the temperature t3 of the coil installation space 17 of the third temperature detection unit T3 becomes higher than the second set temperature (for example, 3°C). The preventive operation is continued (if Yes in step #8).

During execution of the second antifreeze operation, when the temperature t3 of the coil installation space 17 of the third temperature detection section T3 becomes higher than the second set temperature (for example, 3° C.), the operation control section 101 controls the flow rate adjustment valve 15 is closed, the supply of the heat medium to the coil 11 is stopped, and the second antifreeze operation is stopped (in the case of No in step #8, step #9).

[Second embodiment]
This second embodiment is another embodiment of the flow path through which air flows in the first embodiment. Hereinafter, based on FIG. 4, in this second embodiment, a flow path through which air flows, which is different from the first embodiment, will be mainly explained, and the other components will be described with the same reference numerals, and the explanation will be omitted. In FIG. 4, the operating states of the equipment, the opening/closing states of the fifth to eighth dampers D5 to D8, and the air flow indicate the state of the first antifreeze operation.

In the first embodiment, as shown in FIG. 2, an exhaust path 7 is provided to exhaust the indoor air EA in the indoor space 2 to the outside, but in the second embodiment, as shown in FIG. 7, a third return path 31 for returning the indoor air EA of the indoor space 2 to the filter installation space 16 is provided. A fourth return path 32 (corresponding to an indoor air return path) that returns the indoor air EA of the indoor space 2 to the coil installation space 17 is provided in the middle of the third return path 31; A fifth return path 33 returning to the intake path 4 is branched and connected. The third return path 31 is arranged such that there are connection points with the air supply fan 10, a connection point with the fourth return path 32, and a connection point with the fifth return path 33, in order from the upstream side in the air flow direction. ing.

The outside air intake path 4 is provided with a fifth damper D5, and the connection portion of the third return path 31 that connects to the filter installation space 16 is provided with a sixth damper D6. The fifth return path 33 is equipped with a seventh damper D7, and the fourth return path 32 is equipped with an eighth damper D8.

In the first antifreeze operation, as shown in FIG. 4, the operation control unit 101 keeps the air conditioner 1 stopped, puts the air supply fan 10 into the operating state, and sets the communication state switching unit 20 to the non-communication state ( the seventh and eighth dampers D7 and D8 are switched to the open state, and the fifth and sixth dampers D5 and D6 are set to the closed state.

In the first anti-freezing operation, as shown by the arrow in FIG. It is supplied to the coil installation space 17 through 32. The indoor air EA supplied to the coil installation space 17 is returned to the indoor space 2 through the fan installation space 18 and the air supply path 5 because the communication state switching unit 20 is in the non-communication state. In this way, by circulating and supplying the indoor air EA, which has a higher temperature than the outside air OA, to the coil installation space 17 without mixing it with the outside air OA, the coil 11 is warmed by using the heat of the indoor air EA. Therefore, the coil 11 can be prevented from freezing.

By operating the air supply fan 10, the indoor air EA of the indoor space 2 is supplied not only to the coil installation space 17 but also to the outside air intake passage 4. As shown by the arrow in FIG. 4, the operation of the air supply fan 10 causes the indoor air EA in the indoor space 2 to flow through the third return path 31, so that the outside air is taken in through the fifth return path 33. It is supplied to Route 4. Since the fifth damper D5 is in the closed state, the communication between the outside air OA in the outside air intake path 4 and the air conditioner 1 is cut off, and the air flows from the outside air OA side to the air conditioner 1 side in the outside air intake path 4. This prevents any flow from occurring. In this state, by allowing the indoor air EA to flow through the outside air intake path 4 through the fifth return path 33, the flow direction is opposite to the direction of flow from the outside air OA side to the air conditioner 1 side through the outside air intake path 4. By passing the indoor air EA through the room, the outside air intake passage 4 can also be warmed by the indoor air EA.

In the cooling operation or heating operation, although not shown, the operation control unit 101 sets the air conditioner 1 to the cooling operation state or the heating operation state, sets the air supply fan 10 to the operating state, and sets the communication state switching unit 20 to the communication state ( the fifth and sixth dampers D5 and D6 are switched to the open state, and the seventh and eighth dampers D7 and D8 are switched to the closed state. Thereby, indoor air EA is returned to the filter installation space 16 through the third return path 31, and outside air OA is taken in through the outside air intake path 4. Therefore, while indoor air EA and outdoor air OA are mixed in the filter installation space 16, the mixed air is subjected to air conditioning processing (cooling processing or heating processing) by the coil 11, and then supplied to the indoor space 2.

[Third embodiment]
This third embodiment shows another embodiment of the coil 11 in the first embodiment. Hereinafter, based on FIG. 5, the configuration of the coil 11 in this third embodiment will be mainly explained, and the other configurations will be described with the same reference numerals and the explanation will be omitted. In FIG. 5, the operating states of the equipment, the opening/closing states of the first to fourth dampers D1 to D4, and the air flow indicate the state of the first antifreeze operation.

In the first embodiment, as shown in FIG. 2, the coil installation space 17 is provided with one coil 11 for both cooling and heating purposes, but in the third embodiment, as shown in FIG. Thus, the coil installation space 17 is provided with two coils, a cooling coil 11a and a heating coil 11b.

A cooling heat medium (for example, cold water) is circulated and supplied to the cooling coil 11a from an external heat source through a cooling circulation supply path 14a. The cooling circulation supply path 14a is equipped with a cooling flow rate regulating valve 15a. In the cooling operation, the operation control unit 101 opens the cooling flow rate adjustment valve 15a to cool the flowing air in the cooling coil 11a.

A heating medium (for example, hot water) is circulated and supplied to the heating coil 11b from an external heat source through a heating circulation supply path 14b. The heating circulation supply path 14b is equipped with a heating flow rate adjustment valve 15b. In the heating operation, the operation control unit 101 opens the heating flow rate adjustment valve 15b to heat the flowing air with the heating coil 11b.

[Fourth embodiment]
This fourth embodiment shows another embodiment of the coil 11 in the second embodiment, which is another embodiment of the first embodiment. Hereinafter, based on FIG. 6, the configuration of the coil 11 in this fourth embodiment will be mainly explained, and the other configurations will be described with the same reference numerals and the explanation will be omitted. In FIG. 6, the operating states of the equipment, the opening/closing states of the fifth to eighth dampers D5 to D8, and the air flow indicate the state of the first antifreeze operation.

In the second embodiment, as shown in FIG. 4, the coil installation space 17 is provided with one coil 11 for both cooling processing and heating. Similarly, as shown in FIG. 6, the coil installation space 17 is provided with two coils, a cooling coil 11a and a heating coil 11b.

A cooling heat medium (for example, cold water) is circulated and supplied to the cooling coil 11a from an external heat source through a cooling circulation supply path 14a. The cooling circulation supply path 14a is equipped with a cooling flow rate regulating valve 15a. In the cooling operation, the operation control unit 101 opens the cooling flow rate adjustment valve 15a to cool the flowing air in the cooling coil 11a.

A heating medium (for example, hot water) is circulated and supplied to the heating coil 11b from an external heat source through a heating circulation supply path 14b. The heating circulation supply path 14b is equipped with a heating flow rate adjustment valve 15b. In the heating operation, the operation control unit 101 opens the heating flow rate adjustment valve 15b to heat the flowing air with the heating coil 11b.

[Fifth embodiment]
This fifth embodiment shows another embodiment of the coil 11 in the first embodiment. Hereinafter, based on FIG. 7, the configuration of the coil 11 in this fifth embodiment will be mainly explained, and the other configurations will be described with the same reference numerals and the explanation will be omitted. In FIG. 7, the operating states of the equipment, the opening/closing states of the first to fourth dampers D1 to D4, and the air flow indicate the state of the first antifreeze operation.

In the first embodiment, as shown in FIG. 2, the coil installation space 17 is provided with one coil 11 for both cooling and heating purposes, but in the fifth embodiment, as shown in FIG. As shown, the coil installation space 17 is provided with a cooling coil installation space 17a and a heating coil installation space 17b, a cooling coil 11a is arranged in the cooling coil installation space 17a, and a heating coil installation space 17a is provided. A heating coil 11b is arranged in the coil installation space 17b.

The cooling coil installation space 17a and the heating coil installation space 17b are partitioned and shielded (not communicated) by the first partition body 41, and the first partition body 41 includes a cooling coil installation space 17b. A first communication state switching unit 51 (damper) is provided that can switch freely between a communication state in which the coil installation space 17a and the heating coil installation space 17b are communicated and a non-communication state in which they are not communicated.

The cooling coil installation space 17a and the filter installation space 16 are partitioned and shielded (not communicated) by a second partition 42, and the second partition 42 includes a cooling coil installation space. A second communication state switching unit 52 (damper) is provided that can be switched between a communication state in which the filter installation space 17a and the filter installation space 16 are communicated and a non-communication state in which they are not communicated. The cooling coil installation space 17a and the fan installation space 18 are partitioned and shielded (not communicated) by a third partition 43, and the third partition 43 includes a cooling coil installation space. A third communication state switching section 53 (damper) is provided that can switch freely between a communication state in which the fan installation space 17a and the fan installation space 18 are communicated and a non-communication state in which they are not communicated.

The heating coil installation space 17b and the filter installation space 16 are partitioned and shielded (not communicated) by a fourth partition 44, and the fourth partition 44 includes a heating coil installation space. A fourth communication state switching unit 54 (damper) is provided that can be switched between a communication state in which the filter installation space 17b and the filter installation space 16 are communicated and a non-communication state in which they are not communicated. The heating coil installation space 17b and the fan installation space 18 are partitioned and shielded (not communicated) by a fifth partition 45, and the fifth partition 45 includes a heating coil installation space. A fifth communication state switching section 55 (damper) is provided that can be switched between a communication state in which the fan installation space 17b and the fan installation space 18 are communicated and a non-communication state in which they are not communicated.

In this way, since the coil installation space 17 is divided into the cooling coil installation space 17a and the heating coil installation space 17b, air can be passed through the cooling coil 11a and the heating coil 11b independently. In addition to flowing air, it is also possible to cause air to flow through two coils 11a and 11b in the order of cooling coil 11a and heating coil 11b. Therefore, in the fifth embodiment, by switching the open/close states of the first to fifth communication state switching units 51 to 55 in the air conditioner 1, the first anti-freezing operation can be performed, and the cooling operation can be performed as an air conditioning operation. In addition to operation and heating operation, it is configured to be able to perform cooling, dehumidifying, and reheating operation.

Hereinafter, based on FIG. 8, switching of the open/close states of the first to fifth communication state switching sections 51 to 55 in each operation will be described.

(Cooling operation)
In the cooling operation, similarly to the first embodiment, the operation control unit 101 puts the air conditioner 1 into the cooling operation state, puts the air supply fan 10 into the operating state, and switches the first and second dampers D1 and D2 to the open state. , the third and fourth dampers D3 and D4 are in the closed state (see FIG. 1). As a result, outside air OA is taken into the filter installation space 16 of the air conditioner 1 through the outside air intake path 4.

Therefore, as shown in FIG. 8A, the operation control unit 101 switches the second and third communication state switching units 52 and 53 to the open state, and switches the first, fourth, and fifth communication state switching units 51, 54 and 55 are in a closed state. As a result, the outside air OA taken into the filter installation space 16 is made to flow through the cooling coil installation space 17a, and the cooling coil 11a performs a cooling process so that the outside air OA reaches a desired temperature. There is.

(Heating operation)
In the heating operation, similarly to the cooling operation, the operation control unit 101 puts the air conditioner 1 into the cooling operation state, puts the air supply fan 10 into the operating state, switches the first and second dampers D1 and D2 to the open state, and switches the first and second dampers D1 and D2 to the open state. The third and fourth dampers D3 and D4 are in a closed state (see FIG. 1). As a result, outside air OA is taken into the filter installation space 16 of the air conditioner 1 through the outside air intake path 4.

As shown in FIG. 8(b), the operation control unit 101 switches the fourth and fifth communication state switching units 54 and 55 to the open state, and switches the first, second and third communication state switching units 51, 52, 53 is in a closed state. As a result, the outside air OA taken into the filter installation space 16 is made to flow through the heating coil installation space 17b, and the heating coil 11b performs heat treatment so that the outside air OA reaches a desired temperature. There is.

(Cooling dehumidification reheating operation)
In the cooling dehumidification reheating operation, similarly to the cooling operation, the operation control unit 101 puts the air conditioner 1 into the cooling dehumidification reheating operation state, puts the air supply fan 10 into the operating state, and turns the first and second dampers D1 and D2 on. It is switched to the open state, and the third and fourth dampers D3 and D4 are set to the closed state (see FIG. 1). As a result, outside air OA is taken into the filter installation space 16 of the air conditioner 1 through the outside air intake path 4. In addition, in the cooling dehumidification reheating operation state, the air conditioner 1 operates the fan 13, opens the cooling flow rate adjustment valve 15a, and connects the cooling coil 11a with the cooling circulation supply path 14a. By circulating and supplying a heat medium (for example, cold water), the flowing air can be cooled (cooled and dehumidified) by the cooling coil 11a, and heated by opening the heating flow rate regulating valve 15b. By circulating and supplying a heating heat medium (for example, hot water) to the heating coil 11b in the circulation supply path 14b, the flowing air can be heated (reheated) in the heating coil 11b. It is said that

As shown in FIG. 8(c), the operation control unit 101 switches the first, second, and fifth communication state switching units 51, 52, and 55 to the open state, and switches the third and fourth communication state switching units 53, 54 is in a closed state. As a result, the outside air OA taken into the filter installation space 16 is first passed through the cooling coil installation space 17a, and is subjected to cooling treatment (cooling dehumidification) in the cooling coil 11a so that the outside air OA reaches the desired humidity. processing). Next, the outside air OA that has been subjected to the cooling treatment (cooling and dehumidification treatment) is passed through the heating coil installation space 17b, and is heated in the heating coil 11b (reheat treatment) so that the outside air OA reaches a desired temperature. I try to do this. In this way, by sequentially performing a cooling process (cooling and dehumidifying process) and a heating process (reheat process) on the outside air OA, the cooled, dehumidified and reheated outside air OA is supplied to the indoor space 2 as the air SA after the air conditioning process, The indoor space 2 can be cooled and dehumidified.

(First antifreeze operation)
In the first antifreeze operation, as shown in FIG. 7, similarly to the first embodiment, the operation control unit 101 keeps the air conditioner 1 stopped, sets the air supply fan 10 to the operating state, and operates the third antifreeze operation. And the fourth dampers D3 and D4 are switched to the open state, and the first and second dampers D1 and D2 are set to the closed state. Thereby, the indoor air EA in the indoor space 2 is supplied to the heating coil installation space 17b.

As shown in FIGS. 7 and 8(d), the operation control unit 101 switches the first and third communication state switching units 51 and 53 to the open state, and switches the second, fourth, and fifth communication state switching units 52 to the open state. , 54, and 55 are in a closed state. Thereby, the heating coil 11b is warmed by the indoor air EA supplied to the heating coil installation space 17b, and freezing of the heating coil 11b can be prevented. Next, the indoor air EA in the heating coil installation space 17b flows into the cooling coil installation space 17a, and the cooling coil 11a is warmed, thereby preventing the cooling coil 11a from freezing. can. Indoor air EA in the cooling coil installation space 17b is returned to the indoor space 2 through the fan installation space 18 and the air supply path 5.

In the first embodiment, the third temperature detection unit T3 is provided to detect the temperature of the coil installation space 17, but in the fifth embodiment, the coil installation space 17 includes a coil installation space 17a for cooling and a coil installation space 17a for heating. Since the cooling coil installation space 17a and the heating coil installation space 17b are provided with fourth and fifth coil installation spaces 17a and 17b, respectively, the cooling coil installation space 17a and the heating coil installation space 17b have fourth and fifth coil installation spaces 17a and 17b. Temperature detection units T4 and T5 are provided.

Therefore, in the first embodiment, in the flowchart of FIG. 3, in step #4, the first freezing temperature is However, in the fifth embodiment, instead of this, both the detected temperature t4 of the fourth temperature detecting section T4 and the detected temperature t5 of the fifth temperature detecting section T5 are set to the first temperature detecting section T1. The first antifreeze operation is continued until the indoor temperature becomes higher than t1. As a result, the first antifreeze operation is continued until the temperature of both the cooling coil installation space 17a and the heating coil installation space 17b becomes higher than the temperature of the indoor space 2, and the heat contained in the indoor air EA is effectively utilized. This can be used to warm both the cooling coil 11a and the heating coil 11b.

In addition, in the flowchart of FIG. 3, in step #6 and step #8, a process is performed to determine whether or not the detected temperature t3 of the third temperature detection unit T3 is equal to or lower than the second set temperature (for example, 3° C.). However, instead of this, it is determined whether either the detected temperature t4 of the fourth temperature detecting section T4 or the detected temperature t5 of the fifth temperature detecting section T5 is lower than or equal to the second set temperature (for example, 3° C.). Processing will be performed to determine the As a result, when either the cooling coil installation space 17a or the heating coil installation space 17b falls below the second set temperature (for example, 3° C.), the second antifreeze operation is performed, so the cooling coil 11a Both the heating coil 11b and the heating coil 11b can be reliably prevented from freezing.

[Another embodiment]
Other embodiments of the present invention will be described.
Note that the configurations of each embodiment described below are not limited to being applied individually, but can also be applied in combination with the configurations of other embodiments.

(1) In the above embodiment, the operation control unit 101 determines that the first antifreeze condition is satisfied when the outside air temperature t2 of the second temperature detection unit T2 is equal to or lower than the first set temperature (for example, 5°C). , the first antifreeze operation is being performed, but for example, when the temperature t3 of the coil installation space 17 of the third temperature detection section T3 becomes equal to or lower than the set temperature, it can be assumed that the first antifreeze condition is satisfied, and the first antifreeze operation is performed. 1. The conditions for preventing freezing can be changed as appropriate.

(2) In the above embodiment, even if the operation control unit 101 executes the first antifreeze operation, the temperature t3 of the coil installation space 17 of the third temperature detection unit T3 is set to the second set temperature (for example, 3°C). If the condition is below, the second anti-freezing operation is performed, but for example, even if the first anti-freezing operation is performed, the temperature t3 of the coil installation space 17 of the third temperature detection part T3 may not rise. If it continues for a predetermined period of time, the second antifreeze operation can be performed, and the conditions for performing the second antifreeze operation can also be changed as appropriate.

(3) In the above embodiment, as in the case of Yes in step #4 in FIG. For example, although the operation control unit 101 continues the first antifreeze operation, the conditions for continuing the first antifreeze operation can be changed as appropriate. For example, if the temperature t3 of the coil installation space 17 of the third temperature detection section T3 is lower than the indoor temperature t1 of the first temperature detection section T1, the operation control section 101 may cause the first antifreeze operation to continue, or The operation control unit 101 can also continue the first antifreeze operation until the elapsed time from the start of the antifreeze operation reaches a predetermined time.

1 Air conditioner 2 Indoor space 4 Outside air intake path (outside air intake part)
11 Coil 16 Filter installation space (air layer formation space)
17 Coil installation space 21 Indoor air supply section 22 Indoor air circulation section 23 Backflow indoor air circulation section 100 Air conditioning system 101 Operation control section OA Outside air EA Indoor air

Claims (5)

An air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space,
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air ,
The coil installation space is provided in the casing of the air conditioner in a state where it is divided by a partition body,
The indoor air supply section is provided with an indoor air return path that is connected to the coil installation space in addition to an outside air intake section that takes outside air into the air conditioner, and the indoor air return path supplies air to the coil installation space. An air conditioning system that supplies indoor air to indoor spaces . An air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space,
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air,
The air conditioner includes air that can be freely switched between a communication state in which a communication space is formed between the coil installation space and the outside air and a non-communication state in which an air layer is separated from the outside air and is not communicated. A layer forming space is provided ,
The air layer forming space is separated from the coil installation space by a partition and is a filter installation space in which a filter is installed,
The partition body is provided with a communication state switching unit that can switch freely between a communication state in which the filter installation space and the coil installation space are communicated and a non-communication state in which the filter installation space and the coil installation space are not communicated. air conditioning system. An air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space,
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air,
an outside air intake unit that takes outside air into the air conditioner;
In a state in which communication between the outside air and the air conditioner in the outside air intake section is cut off, indoor air from the indoor space is made to flow through the outside air intake section in a direction opposite to the flow direction from the outside air side to the air conditioner side. An air conditioning system equipped with a counterflow indoor air flow section. An air conditioning system having an air conditioner that conditions outside air using a coil and supplies the air after the air conditioning process to an indoor space,
The air conditioner is provided with a coil installation space in which the coil is installed so that it can be freely switched between a communicating state in which it communicates with the outside air and a non-communicating state in which it is separated from the outside air and does not communicate,
When the coil installation space is switched to a non-communicating state, an indoor air supply unit is provided that supplies indoor air of the indoor space to the coil installation space without mixing it with outside air,
An operation control unit that controls the operating state of the air conditioner and the indoor air supply unit is provided,
The operation control unit operates a first anti-freeze operation in which the indoor air supply unit is operated to supply indoor air to the coil installation space as an anti-freeze operation to prevent freezing of the coil, and a first anti-freeze operation in which indoor air is supplied to the coil installation space. and a second anti-freeze operation in which a heat medium is circulated and supplied to the coil,
The operation control unit performs the first anti-freezing operation when a first anti-freezing condition is satisfied, and when the temperature of the coil installation space becomes equal to or lower than a set temperature during execution of the first anti-freezing operation, the operation control unit performs the first anti-freezing operation. Air conditioning system that performs the second antifreeze operation. The indoor air supply unit includes, in addition to the air conditioner, an indoor air circulation unit that circulates indoor air between the indoor space and the coil installation space, and even when the air conditioner is stopped, The air conditioning system according to any one of claims 1 to 4, wherein the indoor air circulation section is configured to be freely operable.

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