Ventilation system

Abstract

To enable heat recovery from return air and make it possible to set an indoor side with positive pressure or negative pressure.SOLUTION: A ventilation system 1 in the present disclosure includes: a refrigerant circuit 60 for circulating a refrigerant in a compressor 52, a first heat exchanger 12 and a second heat exchanger 32; an air supply fan 22 supplying outdoor air to an indoor side; an air exhaust fan 42 for discharging indoor air to an outdoor side; an air supply air course that connects the outdoor side and the indoor side and in which the first heat exchanger 12 and the air supply fan 22 are disposed; an air discharge air course that connects the outdoor side and the indoor side and in which the second heat exchanger 32 and the air exhaust fan 42 are disposed; a supply air detection section 23 for detecting supply air quantity AF1 blown out by the air supply fan 22; a discharge air detection section 43 for detecting discharge air quantity AF2 blown out by the air exhaust fan 42; and a control unit CU. The control unit CU executes air supply control for adjusting rotational frequency of the air supply fan 22 so that the supply air quantity AF1 becomes a target value TV1 and air discharge control for adjusting rotational frequency of the air exhaust fan 42 so that the discharge air quantity AF2 becomes a target value TV2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a ventilation system.

Background Art

[0002] Patent Document 1 describes a ventilation system (heat recovery external conditioning system) capable of performing first type ventilation. This ventilation system includes a heat exchanger, an air supply duct and an exhaust duct that connect the inside and the outside of the target space via the heat exchanger, an air supply fan that supplies air outside the target space to the target space through the air supply duct, and an exhaust fan that exhausts the air inside the target space to the outside of the target space through the exhaust duct.

[0003] In the above ventilation system, the heat exchanger of the heat pump type external conditioner recovers the heat of the return air in the indoor zone and then exhausts it outdoors, and uses this recovered heat to heat-exchange the outside air from outdoors and supply it to the indoor zone.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Since the conventional ventilation system is mainly focused on heat recovery from return air, it is not assumed to appropriately adjust the rotational speeds of the air supply fan and the exhaust fan to set the indoor pressure to positive or negative pressure. An object of the present disclosure is to provide a ventilation system capable of recovering heat from return air and setting the indoor pressure to positive or negative pressure.

Means for Solving the Problems

[0006] (1) The ventilation system of the present disclosure comprises a refrigerant circuit for circulating a refrigerant through a compressor, a first heat exchanger, and a second heat exchanger; an air supply fan for supplying outdoor air to the indoors; an exhaust fan for discharging indoor air to the outdoors; an air supply passage connecting the outdoors and the indoors, in which the first heat exchanger and the air supply fan are located; an exhaust passage connecting the outdoors and the indoors, in which the second heat exchanger and the exhaust fan are located; an air supply detection unit for detecting the amount of air supply blown out by the air supply fan; an exhaust detection unit for detecting the amount of air exhaust blown out by the exhaust fan; and a control unit, wherein the control unit performs air supply control, which adjusts the rotation speed of the air supply fan so that the amount of air supply reaches a target value; and exhaust control, which adjusts the rotation speed of the exhaust fan so that the amount of air exhaust reaches a target value.

[0007] According to the ventilation system of this disclosure, since the second heat exchanger and exhaust fan are located inside an exhaust air passage, heat recovery from the return air is possible. Furthermore, since the control unit performs supply air control and exhaust air control, the indoor environment can be set to positive or negative pressure by appropriately setting the target values ​​for the supply air volume and exhaust air volume. Therefore, the indoor environment can be set to positive or negative pressure while recovering heat from the return air.

[0008] (2) If the ventilation system of the present disclosure further includes an input device that includes a pressure condition representing positive or negative pressure indoors as user-inputtable setting information, the control unit may set the target value of the supply airflow rate higher than the target value of the exhaust airflow rate when the pressure condition is positive pressure, and set the target value of the exhaust airflow rate higher than the target value of the supply airflow rate when the pressure condition is negative pressure.

[0009] In this case, the control unit sets the target supply airflow rate higher than the target exhaust airflow rate when the atmospheric pressure is positive, and sets the target exhaust airflow rate higher than the target supply airflow rate when the atmospheric pressure is negative. This allows the indoor environment to be set to positive or negative pressure according to the atmospheric pressure conditions specified by the user.

[0010] (3) If the ventilation system of the present disclosure further includes a pressure sensor for detecting indoor air pressure, and the setting information that the user can input to the input device includes pressure information for specifying the amount of indoor set pressure, the control unit may determine the target value of the supply air volume and the target value of the exhaust air volume so that the indoor air pressure becomes the set pressure specified by the pressure information.

[0011] In this case, the control unit determines the target values ​​for the supply air volume and exhaust air volume so that the indoor air pressure becomes the set air pressure specified by the air pressure information, thus allowing the indoor air pressure to be set to the set air pressure specified by the user. Therefore, by setting the pressure higher than standard atmospheric pressure, the indoor environment can be set to positive pressure, and by setting the pressure lower than standard atmospheric pressure, the indoor environment can be set to negative pressure.

[0012] (4) In the ventilation system of the present disclosure, the input device may be a wired or wireless remote control device installed in the control room or the room to be ventilated. In this case, the following effects are obtained.

[0013] In other words, installing the remote control device in the control room has the advantage of limiting the operation of setting the indoor air pressure to administrator privileges. Furthermore, installing a remote control device in the room to be ventilated offers the advantage of allowing the user in that room to easily adjust the air pressure settings.

[0014] (5) In the ventilation system of the present disclosure, the control unit may determine the control amount of the refrigerant circuit based on the target value of the supply air volume and the target value of the exhaust air volume.

[0015] In this case, the control unit determines the control amount of the refrigerant circuit based on the target values ​​of the supply air volume and the exhaust air volume. For example, it is possible to control the refrigerant circuit with an appropriate heat recovery amount while maintaining a positive or negative pressure state indoors.

[0016] (6) In the ventilation system of the present disclosure, the supply fan includes a first supply fan that supplies outdoor air to a first indoor room and a second supply fan that supplies outdoor air to a second indoor room, the exhaust fan includes a first exhaust fan that discharges the air from the first room to the outside and a second exhaust fan that discharges the air from the second room to the outside, the supply detection unit includes a first supply detection unit for detecting a first supply air volume blown out by the first supply fan and a second supply detection unit for detecting a second supply air volume blown out by the second supply fan, and the exhaust detection unit detects the first exhaust air volume blown out by the first exhaust fan The supply air control includes a first exhaust detection unit for detecting airflow and a second exhaust detection unit for detecting a second exhaust airflow discharged by the second exhaust fan, and the supply air control includes a first supply air control that adjusts the rotation speed of the first supply air fan so that the first supply airflow becomes a target value and a second supply air control that adjusts the rotation speed of the second supply air fan so that the second supply airflow becomes a target value, and the exhaust air control may include a first exhaust air control that adjusts the rotation speed of the first exhaust fan so that the first exhaust airflow becomes a target value and a second exhaust air control that adjusts the rotation speed of the second exhaust fan so that the second exhaust airflow becomes a target value.

[0017] In this case, the control unit performs the first supply air control, first exhaust air control, second supply air control, and second exhaust air control described above. By appropriately setting the target values ​​for the first supply air volume, first exhaust air volume, second supply air volume, and second exhaust air volume, the first and second rooms can be set to positive or negative pressure, respectively. Therefore, the first and second rooms can be set to positive or negative pressure while recovering heat from the return air.

[0018] (7) If the ventilation system of the present disclosure further includes an input device that includes a first atmospheric pressure condition representing positive or negative pressure of the first room and a second atmospheric pressure condition representing positive or negative pressure of the second room as user-inputtable setting information, the control unit may set the target value of the first supply airflow rate higher than the target value of the first exhaust airflow rate if the first atmospheric pressure condition is positive pressure, set the target value of the first exhaust airflow rate higher than the target value of the first supply airflow rate if the first atmospheric pressure condition is negative pressure, set the target value of the second supply airflow rate higher than the target value of the second exhaust airflow rate if the second atmospheric pressure condition is positive pressure, and set the target value of the second exhaust airflow rate higher than the target value of the second supply airflow rate if the second atmospheric pressure condition is negative pressure.

[0019] In this case, the control unit sets the target value of the first supply airflow rate higher than the target value of the first exhaust airflow rate when the first atmospheric pressure condition is positive, and sets the target value of the first exhaust airflow rate higher than the target value of the first supply airflow rate when the atmospheric pressure condition is negative. Thus, the first room can be set to positive or negative pressure according to the atmospheric pressure condition set by the user. Furthermore, the control unit sets the target value of the second supply airflow rate higher than the target value of the second exhaust airflow rate when the second atmospheric pressure condition is positive, and sets the target value of the second exhaust airflow rate higher than the target value of the second supply airflow rate when the atmospheric pressure condition is negative. This allows the second room to be set to positive or negative pressure according to the atmospheric pressure condition specified by the user.

[0020] (8) The ventilation system of the present disclosure further includes a first air pressure sensor for detecting the air pressure in the first room and a second air pressure sensor for detecting the air pressure in the second room. When the setting information that can be input by the user to the input device includes first air pressure information for designating the magnitude of the set air pressure in the first room and second air pressure information for designating the magnitude of the set air pressure in the second room, the control unit determines the target value of the first air supply air volume and the target value of the first exhaust air volume so that the air pressure in the first room becomes the set air pressure designated by the first air pressure information, and determines the target value of the second air supply air volume and the target value of the second exhaust air volume so that the air pressure in the second room becomes the set air pressure designated by the second air pressure information.

[0021] In this case, since the control unit determines the target value of the first air supply air volume and the target value of the first exhaust air volume so that the indoor air pressure becomes the set air pressure designated by the first air pressure information, the air pressure in the first room can be set to the set air pressure designated by the user. [[ID=*]] Also, since the control unit determines the target value of the second air supply air volume and the target value of the second exhaust air volume so that the indoor air pressure becomes the set air pressure designated by the second air pressure information, the air pressure in the second room can be set to the set air pressure designated by the user. Therefore, if different set air pressure values are specified for the first room and the second room, ventilation with an air pressure difference between the rooms can be performed.

[0022] (9) In the ventilation system of the present disclosure, the input device may be a wired or wireless communication-capable remote control device installed in the management room or the first and second rooms. In this case, there are the following effects.

[0023] That is, when the remote control device is installed in the management room, there is an advantage that the setting work of the air pressure in the first and second rooms can be limited to the administrator authority. Also, when the remote control device is installed in the first and second rooms respectively, there is an advantage that the users in the first and second rooms can easily perform the air pressure setting work.

[0024] (10) In the ventilation system of the present disclosure, the control unit may determine a control amount of the refrigerant circuit based on the target value of the first supply air volume, the target value of the second supply air volume, the target value of the first exhaust air volume, and the target value of the second exhaust air volume.

[0025] In this case, since the control unit determines the control amount of the refrigerant circuit based on the target value of the first supply air volume, the target value of the first exhaust air volume, the target value of the second supply air volume, and the target value of the second exhaust air volume, for example, while maintaining the positive pressure state or negative pressure state of the first and second rooms, the refrigerant circuit can be controlled with an appropriate heat recovery amount.

Brief Description of the Drawings

[0026] [Figure 1] It is a longitudinal sectional view of a building showing an example of the overall configuration of the ventilation system according to the first embodiment. [Figure 2] It is a block diagram showing an example of the control system of the control unit. [Figure 3] It is a flowchart showing an example of the information processing of the main controller. [Figure 4] It is a flowchart showing an example of the determination process of the target values of the supply and exhaust air volumes. [Figure 5] It is a flowchart showing an example of the information processing of the supply and exhaust controllers. [Figure 6] It is a longitudinal sectional view of a building showing an example of the overall configuration of the ventilation system according to the second embodiment. [Figure 7] It is a block diagram showing an example of the control system of the control unit. [Figure 8] It is a flowchart showing an example of the information processing of the main controller. [Figure 9] It is a flowchart showing an example of the determination process of the target values of the supply and exhaust air volumes. [Figure 10] It is a flowchart showing an example of the information processing of the supply and exhaust controllers.

Modes for Carrying Out the Invention

[0027] <First Embodiment> [Overall configuration of the ventilation system] Figure 1 is a longitudinal cross-sectional view of a building showing an example of the overall configuration of ventilation system 1. In Figure 1, the reference numerals "OA", "SA", "RA", and "EA" have the following meanings, respectively.

[0028] OA: This refers to outdoor air (outside air). It is also the air that System 1 draws in from outside. SA: This is the air (supply air) that System 1 sends into the building. RA: This is indoor air (return air). It is also the air that System 1 draws in from indoors. EA: This is the air (exhaust) that System 1 expels outdoors.

[0029] The ventilation system 1 of the first embodiment is a system that performs Type 1 ventilation to an indoor target space RM while controlling the temperature of the supply air SA and recovering heat from the return air RA. The target space RM is, for example, the indoor space of various buildings such as office buildings, hospitals, and factories. The target space RM is preferably a highly airtight room for a specified purpose, but it may also be an indoor corridor, staircase, or entrance, for example. Furthermore, the target space RM may also have an indoor unit 2 of an air conditioning system separate from the ventilation system 1.

[0030] As shown in Figure 1, the ventilation system 1 comprises a heat exchange unit 10 on the utilization side (supply side), a supply air unit 20, a heat exchange unit 30 on the recovery side (exhaust side), an exhaust unit 40, a compressor unit 50, and a refrigerant circuit 60. The heat exchange unit 10 and the air supply unit 20 are installed in the ceiling space of the target space RM, while the heat exchange unit 30, the exhaust unit 40, and the compressor unit 50 are installed inside the walls of the target space RM.

[0031] The ventilation system 1 further includes an input device 70, which is an input device that allows user operation input, and a pressure sensor 80. The input device 70 is, for example, a remote control device mounted on the wall of the target space RM. The input device 70 may be installed in a room separate from the target space RM, such as a control room (not shown). The pressure sensor 80 is a sensor that monitors the atmospheric pressure indoors. The pressure sensor 80 can be connected via wired or wireless communication in accordance with a predetermined communication standard and can be mounted on the ceiling surface of the target space RM.

[0032] The installation locations of each unit shown in Figure 1 are just examples; for example, the heat exchange unit 30 and the exhaust unit 40 may be placed in the ceiling space, and the return air RA may be drawn in from the ceiling side. Furthermore, at least one of the heat exchange unit 30, exhaust unit 40, and compressor unit 50 may be installed outdoors.

[0033] [Components of each unit] The user-side heat exchange unit 10 has a casing 11 and a plurality of devices housed in the casing 11. The plurality of devices include a user-side heat exchanger (hereinafter referred to as the "first heat exchanger") 12, which is an element of the refrigerant circuit 60, and an outside air temperature sensor 13. The first heat exchanger 12 is, for example, a cross-fin tube type or a microchannel type heat exchanger, and the refrigerant flowing inside the first heat exchanger 12 is used to exchange heat with the outside air OA.

[0034] The air supply unit 20 has a casing 21 and a plurality of devices housed in the casing 21. The plurality of devices include an air supply fan 22, an air supply detection unit 23, an air supply temperature sensor 24, and an air supply controller 25. The air supply fan 22 is, for example, a centrifugal fan whose fan speed can be controlled. The air supply detection unit 23 is, for example, an airflow sensor for detecting airflow, or a sensor for detecting physical quantities that are the source of airflow calculation, such as wind speed, differential pressure, or fan speed (hereinafter referred to as "airflow equivalent amount"). Therefore, if the air supply controller 25 has a fan speed counting function, the air supply controller 25 also functions as the air supply detection unit 23.

[0035] The air supply controller 25 is a control module that includes, for example, a circuit board and integrated circuits such as a CPU (Central Processing Unit) and memory mounted on the circuit board. The integrated circuits may include at least one of FPGA (Field-Programmable Gate Array) and ASIC (Application-Specific IC). The air supply controller 25 is capable of performing predetermined information processing, such as controlling communication with other controllers and sensors in accordance with a predetermined communication standard, and controlling the fan speed so that the airflow of the air supply fan 22 reaches a target value.

[0036] The recovery-side heat exchange unit 30 has a casing 31 and a plurality of components housed in the casing 31. The plurality of components include a recovery-side heat exchanger (hereinafter referred to as the "second heat exchanger") 32, which is an element of the refrigerant circuit 60, and a return air temperature sensor 33. The second heat exchanger 32 is, for example, a cross-fin tube type or a microchannel type heat exchanger, and the refrigerant flowing inside the second heat exchanger 32 is used to exchange heat with the return air RA.

[0037] The exhaust unit 40 has a casing 41 and a plurality of devices housed in the casing 41. The plurality of devices include an exhaust fan 42, an exhaust detection unit 43, and an exhaust controller 44. The exhaust fan 42 is, for example, a centrifugal fan whose fan speed can be controlled. The exhaust detection unit 43 is, for example, an airflow sensor for detecting airflow volume, or a sensor for detecting an equivalent amount of airflow volume. Therefore, if the exhaust controller 44 has a fan speed counting function, the exhaust controller 44 also functions as the exhaust detection unit 43.

[0038] The exhaust controller 44 is, for example, a control module including a circuit board and integrated circuits such as a CPU and memory mounted on the circuit board. The integrated circuits may include at least one of FPGAs and ASICs. The exhaust controller 44 is capable of performing predetermined information processing, such as controlling communication with other controllers and sensors in accordance with predetermined communication standards, and controlling the fan speed of the exhaust fan 42 so that the airflow reaches a target value.

[0039] The compressor unit 50 has a casing 51 and a plurality of components housed in the casing 51. The plurality of components include a compressor 52, a four-way valve 53, an expansion valve 54, and a main controller 55. The refrigerant circuit 60 is a circuit that circulates refrigerant to the compressor 52, the first heat exchanger 12, and the second heat exchanger 32, and includes the compressor 52, a four-way valve 53, an expansion valve 54, the first heat exchanger 12, the second heat exchanger 32, and refrigerant piping 61 connecting them.

[0040] The main controller 55 is, for example, a control module including a circuit board and integrated circuits such as a CPU and memory mounted on the circuit board. The integrated circuits may include at least one of FPGAs and ASICs. The main controller 55 is capable of performing communication control with other controllers and sensors in accordance with a predetermined communication standard, and of performing predetermined information processing such as determining the control amount of the refrigerant circuit 60 according to the ventilation rate.

[0041] [Air supply and exhaust ducts for ventilation systems] In the ceiling space of the target space RM, the intake port of the casing 11 is connected to the outdoor air supply port by the duct d1. In the ceiling space of the target space RM, the intake port of casing 21 is airtightly connected to the outlet port of casing 11 by duct d2. The outlet port of casing 21 is exposed from the ceiling surface into the target space RM.

[0042] Therefore, the air passage formed by duct d1, casing 11, duct d2, and casing 21 connects the outdoors and indoors, and constitutes an "air supply passage" in which the first heat exchanger 12 and the air supply fan 22 are located.

[0043] Alternatively, a discharge unit (not shown) having a filter and a wind deflector may be connected to the discharge side of the casing 21 via a duct or directly, and the discharge unit may be exposed from the ceiling surface to the target space RM. In addition, a humidification unit and a filter unit (not shown) for collecting fine particles (such as PM2.5) may be provided in the middle of the ducts d1 and d2. In this case, the casings of each of the above units may also become components of the air supply passage.

[0044] In the space under the floor of the target area RM, the intake port of the casing 31 is airtightly connected to the air supply port on the floor surface by a duct d3 consisting of branch pipes. Within the wall of the target space RM, the intake port of casing 41 is airtightly connected to the outlet port of casing 31 by duct d4. The outlet port of casing 41 leads to an outdoor exhaust port by duct d5.

[0045] Therefore, the air passage formed by duct d3, casing 31, duct d4, casing 41, and duct d5 connects the outdoors and indoors, and constitutes an "exhaust air passage" in which the second heat exchanger 32 and exhaust fan 42 are located.

[0046] When the intake fan 22 is driven, the intake air passage duct d1, casing 11, and duct d2 become negatively pressurized, and outside air OA is drawn into duct d1. At this time, the outside air temperature sensor 13 detects the temperature of the outside air OA before heat exchange with the first heat exchanger 12. The air that has exchanged heat with the first heat exchanger 12 is sent indoors as supply air SA through the duct d2 and casing 21. At this time, the supply air temperature sensor 24 detects the temperature of the supply air SA.

[0047] When the exhaust fan 42 is driven, the exhaust air passage duct d4, casing 31, and duct d3 become negatively pressurized, and the return air RA is drawn into duct d3. At this time, the return air temperature sensor 33 detects the temperature of the return air RA before heat exchange with the second heat exchanger 32. The air that has exchanged heat with the second heat exchanger 32 is sent outdoors as exhaust EA through the casing 41 and duct d5.

[0048] In the ventilation system 1 shown in Figure 1, the heat exchange unit 10 may be located on the outlet side (downstream side in the air supply direction) of the air supply unit 20 as an air supply duct. Similarly, the heat exchange unit 30 may be located on the outlet side (downstream side in the exhaust direction) of the exhaust unit 40 as an exhaust duct. In the ventilation system 1 shown in Figure 1, the heat exchange unit 10 and the supply air unit 20 may be integrated units housed in the same casing. Similarly, the heat exchange unit 30 and the exhaust unit 40 may be integrated units housed in the same casing.

[0049] [Refrigerant circuit components and temperature control operation] The compressor 52 is an element of the refrigerant circuit 60 that draws in low-pressure gaseous refrigerant and discharges high-pressure gaseous refrigerant. The compressor 52 is a variable-capacity type (variable-capacity type) whose capacity can be changed, for example, by inverter control of an electric motor. However, the compressor 52 may also be a fixed-capacity type, or it may be a type in which two or more units are connected in parallel.

[0050] The expansion valve 54 is, for example, an electrically operated valve for regulating the flow rate and pressure of the refrigerant in the piping 61. The refrigerant pressure to the first heat exchanger 12 is regulated by controlling the opening degree of the expansion valve 54. The four-way valve 53 is a valve that reverses the direction of refrigerant flow in the circuit, switching the refrigerant discharged by the compressor 52 to either the first heat exchanger 12 or the second heat exchanger 32. Therefore, the temperature-controlled operation that the ventilation system 1 can perform includes "cold air supply," which cools the outside air OA and supplies it indoors, and "warm air supply," which heats the outside air OA and supplies it indoors.

[0051] Specifically, in the case of supplying cold air, where the cold air SA is supplied after the outside air OA has been cooled, the four-way valve 53 is held in the state shown by the solid line in Figure 1. In this case, the first heat exchanger 12 on the utilization side functions as an evaporator to cool the outside air OA, and the second heat exchanger 32 on the recovery side functions as a condenser to heat the return air RA. This heating of the return air RA corresponds to heat recovery from the return air RA.

[0052] Conversely, in the case of supplying warm air, where the warm air after heating the outside air OA is used as the supply air SA, the four-way valve 53 is held in the state shown by the dashed line in Figure 1. In this case, the first heat exchanger 12 on the utilization side functions as a condenser to heat the outside air OA, and the second heat exchanger 32 on the recovery side functions as an evaporator to cool the return air RA. This cooling of the return air RA corresponds to heat recovery from the return air RA.

[0053] In the ventilation system 1 of this embodiment, the four-way valve 53 of the refrigerant circuit 60 may be omitted. In this case, the first heat exchanger 12 is used for either the evaporator or the condenser, and the ventilation system 1 performs either the supply of cold air or the supply of warm air.

[0054] [Ventilation system control system] Figure 2 is a block diagram showing an example of the control system for ventilation system 1. The meanings of the parameters included in Figure 2 are as follows: SI: Configuration information that can be input to the input device 70. For example, it includes the following SIa to SIc and SIt.

[0055] SIa: Barometric pressure conditions representing positive or negative pressure. SIb: Pressure information used to specify the level of indoor pressure (e.g., "high pressure," "medium pressure," and "low pressure," or numerical information specified in hPa values). SIc: Information on the type of supply airflow defined in stages (e.g., "gentle breeze," "weak breeze," "medium breeze," and "strong breeze," or identification numbers from "Level 1" to "Level 4") SIt: Intake air SA set temperature

[0056] TS: Detection result of supply air temperature sensor 24 (supply air temperature of supply air fan) TO: Detection result of outside air temperature sensor 13 (outside air temperature) TR: Detection result of return air temperature sensor 33 (return air temperature)

[0057] AF1: Airflow from the intake fan 22 (intake airflow) However, if the air supply detection unit 23 is an airflow sensor, AF1 will be the detection result of that sensor, and if the air supply detection unit 23 is a sensor that detects an amount equivalent to airflow, AF1 will be the airflow calculated from the detection result of that sensor. AF1 may also be the airflow calculated from the fan rotation speed counted by the air supply controller 25.

[0058] AF2: Airflow from exhaust fan 42 (exhaust airflow) However, if the exhaust detection unit 43 is an airflow sensor, AF2 will be the detection result of that sensor, and if the exhaust detection unit 43 is a sensor that detects an amount equivalent to airflow, AF2 will be the airflow calculated from the detection result of that sensor. AF2 may also be the airflow calculated from the fan rotation speed counted by the exhaust controller 44.

[0059] PR: Detection results of pressure sensor 80 (atmospheric pressure in the target space RM) TV1: Target value of the airflow volume (supply air volume) blown out by the supply fan 22. TV2: Target value of the airflow volume (exhaust airflow) blown out by exhaust fan 42. CQ: Controlled quantity for refrigerant circuit 60 (compressor discharge rate, refrigerant flow rate or direction, etc.)

[0060] As shown in Figure 2, the control system of the ventilation system 1 includes a control unit CU consisting of a group of controllers that communicate via wired or wireless means. The control unit CU comprises a main controller 55, a supply air controller 25, and an exhaust air controller 44.

[0061] The main controller 55 is connected to the input device 70. When a user inputs an SI to the input device 70, the input device 70 transmits the SI to the main controller 55. The main controller 55 records the received SI in its memory. The main controller 55 is connected to each of the temperature-related sensors 24, 13, and 33. The main controller 55 receives TS, TO, and TR from each of the sensors 24, 13, and 33.

[0062] If the supply air temperature sensor 24 is connected to the supply air controller 25, the supply air controller 25 may be used as a relay node to transmit the TS to the main controller 55. The main controller 55 is connected to the supply air controller 25, the second controller 25B, and the exhaust controller 44.

[0063] If the main controller 55 determines TV1, it sends the determined TV1 to the air supply controller 25, and if it determines TV2, it sends the determined TV2 to the exhaust controller 44. The main controller 55 is connected to the compressor 52, the four-way valve 53, and the expansion valve 54. When the main controller 55 determines a CQ, it outputs the determined CQ to at least one of the compressor 52, the four-way valve 53, and the expansion valve 54.

[0064] The air supply controller 25 is connected to the air supply fan 22, the air supply detection unit 23, and the pressure sensor 80. The air supply controller 25 forwards the PR received from the pressure sensor 80 to the main controller 55. If the pressure sensor 80 is connected to the main controller 55, the PR is sent directly to the main controller 55.

[0065] If the air supply detection unit 23 is an airflow sensor, the air supply controller 25 sets the detection result received from the detection unit 23 as AF1. If the air supply detection unit 23 is a sensor that measures the amount of airflow, the air supply controller 25 calculates AF1 from the detection result received from the detection unit 23. The air supply controller 25 may also use the airflow calculated from the fan rotation speed it counts as AF1. When the air intake controller 25 receives TV1, it calculates the fan speed based on TV1 and AF1, and outputs the calculated speed to the air intake fan 22.

[0066] The exhaust controller 44 is connected to the exhaust fan 42 and the exhaust detection unit 43. If the exhaust detection unit 43 is an airflow sensor, the exhaust controller 44 sets the detection result received from the detection unit 43 as AF2. If the exhaust detection unit 43 is a sensor that measures the amount of airflow, the exhaust controller 44 calculates AF2 from the detection result received from the detection unit 43. The exhaust controller 44 may also use the airflow calculated from the fan rotation speed it counts as AF2. When the exhaust controller 44 receives TV2, it calculates the fan speed based on TV2 and AF2, and outputs the calculated speed to the exhaust fan 42.

[0067] [Information processing of the main controller] Figure 3 is a flowchart showing an example of information processing by the main controller 55. As shown in Figure 3, after startup, the main controller 55 reads the latest configuration information SI from memory (step ST11). Next, the main controller 55 acquires the temperature detection results TS, TO, and TR (step ST12), and acquires PR, which is the indoor atmospheric pressure detection result in the target space RM (step ST13).

[0068] Next, the main controller 55 performs a determination process for TV1, which is the target value for the supply airflow rate, and TV2, which is the target value for the exhaust airflow rate (step ST14). Details of this determination process (Figure 4) will be described later. Next, the main controller 55 performs the calculation process for CQ, which is the control amount for the refrigerant circuit 60 (step ST15). This calculation process calculates CQ based on TV1 and TV2 determined in the current control cycle.

[0069] For example, the main controller 55 calculates the temperature control load required to bring the supply air SA to the set temperature Sit from TV1 and TV2 determined in the current control cycle, and from the current TS, TO, and TR, and then determines the control amount CQ of the refrigerant circuit 60 based on the calculated temperature control load.

[0070] Next, the main controller 55 transmits the determined TV1 and TV2 to the respective controllers 25 and 44 (step ST16). Specifically, the main controller 55 transmits TV1 to the air intake controller 25 and TV2 to the exhaust controller 44.

[0071] Next, the main controller 55 controls the refrigerant circuit 60 according to the CQ determined in step ST15 (step ST17), and determines whether a predetermined control cycle (e.g., 30 seconds) has elapsed (step ST18). If the result of step ST18 is positive, the main controller 55 returns the process to before step ST11.

[0072] If the result of step ST18 is negative, the main controller 55 determines whether or not a termination command has been received from the input device 70 (step ST19). If the result of step ST19 is negative, the main controller 55 returns the process to before ST18. If the result of step ST19 is positive, the main controller 55 terminates the process.

[0073] [Process for determining target values ​​for supply and exhaust airflow rates] Figure 4 is a flowchart showing an example of the process for determining target values ​​for supply and exhaust airflow rates (step ST14 in Figure 3). Here, it is assumed that there are four types of supply airflow rates that can be specified in SIc: light breeze, weak breeze, medium breeze, and strong breeze. Furthermore, the memory of the main controller 55 is assumed to hold a reference table that defines the correspondence between the supply airflow rate type and the target value TV1 of the supply airflow rate.

[0074] As shown in Figure 4, the main controller 55 determines TV1 from the type of supply airflow rate included in SIc (step ST31). Specifically, the main controller 55 reads the target value of the supply airflow rate corresponding to the type specified in SIc from the reference table, and sets the read target value as TV1.

[0075] Next, the main controller 55 determines whether or not an SIa input has been received (step ST32). This determination can be made by checking whether or not SIa is recorded in memory. If the result of step ST32 is negative, the main controller 55 determines whether or not an SIb input was received (step ST33). This determination can be made by checking whether or not the SIb is recorded in memory.

[0076] If the result of step ST33 is negative, the main controller 55 sets TV2 to the same value as TV1 (step ST35). Thus, if there are no inputs for SIa and SIb, the main controller 55 sets target values ​​TV1 and TV2 so that the supply airflow rate and exhaust airflow rate are balanced. If the result of step ST33 is positive, the main controller 55 calculates TV2 from the determined TV1 and the set pressure specified in SIb.

[0077] For example, the main controller 55 stores in advance a relational expression between the air pressure (e.g., static pressure) in the target space RM, and the air duct length, the supply air volume, and the exhaust air volume of the ventilation system 1, and applies the set air pressure, TV1, and the air duct length of system 1 to this relational expression to calculate TV2. If the determination result in step ST32 is affirmative, the main controller 55 determines whether the type specified by SIa is positive pressure or negative pressure (step ST34).

[0078] If the determination result in step ST34 is "positive pressure", the main controller 55 determines an appropriate TV2 under the condition of TV1 > TV2 (step ST37). For example, the main controller 55 calculates TV2 by the following calculation formula. Note that ΔTVa is a differential air volume value for positive pressure preset according to the volume of the target space RM and the like. TV2 = TV1 - ΔTVa

[0079] If the determination result in step ST34 is "negative pressure", the main controller 55 determines an appropriate TV2 under the condition of TV1 < TV2 (step ST38). For example, the main controller 55 calculates TV2 by the following calculation formula. Note that ΔTVb is a differential air volume value for negative pressure preset according to the volume of the target space RM and the like. TV2 = TV1 + ΔTVb

[0080] 〔Information Processing of Supply and Exhaust Controllers〕 FIG. 5 is a flowchart showing an example of the information processing of the supply and exhaust controllers 25 and 44. In FIG. 5, the suffix "j" is an identification number representing supply or exhaust. j = 1 means supply air, and j = 2 means exhaust air. Therefore, FIG. 5 represents the information processing of the supply controller 25 when j = 1, and represents the information processing of the exhaust controller 44 when j = 2.

[0081] As shown in FIG. 5, after startup, each of the controllers 25 and 44 determines whether it has received TVj from the main controller 55 (step ST51). If received, it acquires AFj from the detection results of the detection units 23 and 43 of its own unit (step ST52).

[0082] Next, each of the controllers 25 and 44 compares the magnitudes of AFj and TVj (step ST53), and executes the following processing according to the comparison result. That is, when AFj < TVj, each of the controllers 25 and 44 increases the rotation speed of the fans 22 and 42 of its own unit by a predetermined amount (step ST54). When AFj = TVj, it maintains the rotation speed (step ST55). When AFj > TVj, it decreases the rotation speed by a predetermined amount (step ST56).

[0083] Thus, the air supply and exhaust controllers 25 and 44 autonomously adjust the rotation speed of the fans 22 and 42 of their own units based on TVj received from the main controller 55 and AFj detectable by the detection units 23 and 43 of their own units.

[0084] <Operational Effects of the First Embodiment> (1) According to the ventilation system 1 of the first embodiment, since it connects the outdoors and the indoors and has an exhaust air duct in which the second heat exchanger 32 and the exhaust fan 42 are arranged inside, heat recovery from the return air is possible. Also, since the control unit CU (specifically, the air supply and exhaust controllers 25 and 44) executes the following air supply control and exhaust control, by appropriately setting the target values TV1 and TV2 of the air supply air volume AF1 and the exhaust air volume AF2, the indoor pressure can be set to positive or negative pressure. Therefore, it is possible to set the indoor pressure to positive or negative pressure while recovering heat from the return air RA.

[0085] Air supply control: Control for adjusting the rotation speed of the air supply fan 22 so that the air supply air volume AF1 becomes the target value TV1 Exhaust control: Control for adjusting the rotation speed of the exhaust fan 42 so that the exhaust air volume AF2 becomes the target value TV2

[0086] (2) According to the ventilation system 1 of the first embodiment, the control unit CU (specifically, the main controller 55) sets the target value TV1 of the supply air volume higher than the target value TV2 of the exhaust air volume when the atmospheric pressure condition SIa is positive, and sets the target value TV2 of the exhaust air volume higher than the target value TV1 of the supply air volume when the atmospheric pressure condition SIa is negative. Thus, the indoor environment can be set to positive or negative pressure according to the atmospheric pressure condition SIa specified by the user.

[0087] (3) According to the ventilation system 1 of the first embodiment, the control unit CU (specifically, the main controller 55) determines the target value TV1 for the supply air volume and the target value TV2 for the exhaust air volume so that the indoor air pressure becomes the set air pressure specified by the air pressure information SIb, so that the indoor air pressure can be set to the set air pressure specified by the user. Therefore, by setting the pressure higher than standard atmospheric pressure, the indoor environment can be set to positive pressure, and by setting the pressure lower than standard atmospheric pressure, the indoor environment can be set to negative pressure.

[0088] (4) The ventilation system 1 of the first embodiment has the following effects: In other words, if the input device is a remote control device 70 installed in the control room, there is the advantage that the operation of setting the indoor air pressure can be limited to administrator privileges. Furthermore, when the remote control device 70 is installed in the room to be ventilated, there is the advantage that the user in the room to be ventilated can easily perform the task of setting the air pressure.

[0089] (5) According to the ventilation system 1 of the first embodiment, the control unit CU (specifically, the main controller 55) determines the control amount CQ of the refrigerant circuit 60 based on the target value TV1 of the supply air volume and the target value TV2 of the exhaust air volume. For example, the refrigerant circuit 60 can be controlled with an appropriate amount of heat recovery while maintaining a positive or negative pressure state indoors.

[0090] <Second Embodiment> [Overall configuration of the ventilation system] Figure 6 is a longitudinal cross-sectional view of a building showing an example of the overall configuration of ventilation system 4. The ventilation system 4 of the second embodiment is a system that performs Type 1 ventilation for multiple target spaces (indoor rooms) RM1, RM2 partitioned by interior walls 3, while controlling the temperature of the supply air SA and recovering heat from the return air RA.

[0091] The following description will focus on the differences from the ventilation system 1 of the first embodiment. Common elements with the first embodiment will be denoted by the same reference numerals in the drawings and will not be described further. As shown in Figure 6, the ventilation system 4 comprises a first supply air unit 20A and a first exhaust air unit 40A installed in the target space (first room) RM1, and a second supply air unit 20B and a second exhaust air unit 40A installed in the target space (second room) RM2.

[0092] The heat exchange unit 10, the first air supply unit 20A, and the second air supply unit 20B are installed in the ceiling space of the target spaces RM1 and RM2. The first exhaust unit 40A and the second exhaust unit 40B are installed under the floor of the target spaces RM1 and RM2. The heat exchange unit 30 and the compressor unit 50 are installed inside the wall of the target space RM1.

[0093] The ventilation system 4 further includes first and second input devices 70A and 70B, which are input devices that can be operated by the user, and first and second atmospheric pressure sensors 80A and 80B. The first input device 70A is, for example, a remote control device mounted on the wall of the target space RM1. The second input device 70B is, for example, a remote control device mounted on the wall of the target space RM2.

[0094] The first and second input devices 70A and 70B may be installed in a room separate from the target spaces RM1 and RM2, such as a control room (not shown). In this case, the first and second input devices 70A and 70B may be separate remote control devices of the same product, or they may be an integrated remote control device capable of setting each target space RM1 and RM2 with a single unit.

[0095] The first and second atmospheric pressure sensors 80A and 80B are sensors that monitor indoor atmospheric pressure, and both are capable of wired or wireless communication in accordance with a predetermined communication standard. The first atmospheric pressure sensor 80A is mounted on the ceiling surface of the target space RM1, and the second atmospheric pressure sensor 80B is mounted on the ceiling surface of the target space RM2.

[0096] The installation locations of each unit shown in Figure 6 are examples only. For example, the heat exchange unit 30 and the first and second exhaust units 40A and 40B may be placed in the ceiling space, and the return air RA may be drawn in from the ceiling side. Alternatively, at least one of the heat exchange unit 30 and the compressor unit 50 may be installed outdoors.

[0097] [Components of the air intake unit and exhaust unit] The first air supply unit 20A includes a casing 21A and a plurality of devices housed in the casing 21A. The plurality of devices include a first air supply fan 22A, a first air supply detection unit 23, a first air supply temperature sensor 24A, and a first air supply controller 25A. The first air supply fan 22A is, for example, a centrifugal fan whose fan speed can be controlled. The first air supply detection unit 23A is, for example, an airflow sensor for detecting airflow volume, or a sensor for detecting an equivalent amount of airflow volume. Therefore, if the first air supply controller 25A has a fan speed counting function, the first air supply controller 25A also functions as the first air supply detection unit 23A.

[0098] The first air supply controller 25A is a control module that includes, for example, a circuit board and an integrated circuit such as a CPU and memory mounted on the circuit board. The integrated circuit may include at least one FPGA. The first air supply controller 25A is capable of performing predetermined information processing, such as communication control with other controllers and sensors in accordance with a predetermined communication standard, and control of the fan speed so that the airflow of the first air supply fan 22A reaches a target value.

[0099] The second air supply unit 20B includes a casing 21B and a plurality of components housed within the casing 21B. These components include a second air supply fan 22B, a second air supply detection unit 23B, a second air supply temperature sensor 24B, and a second controller 25B. The second air supply fan 22B is, for example, a centrifugal fan whose fan speed can be controlled. The second air supply detection unit 23B is, for example, an airflow sensor for detecting airflow volume, or a sensor for detecting an equivalent amount of airflow volume. Therefore, if the second air supply controller 25B has a fan speed counting function, the second air supply controller 25B also functions as the second air supply detection unit 23B.

[0100] The second air supply controller 25B is, for example, a control module including a circuit board and integrated circuits such as a CPU and memory mounted on the circuit board. The integrated circuits may include at least one of FPGAs and ASICs. The second air supply controller 25B is capable of performing predetermined information processing, such as communication control with other controllers and sensors in accordance with a predetermined communication standard, and control of the fan speed so that the airflow of the second air supply fan 22B reaches a target value.

[0101] The first exhaust unit 40A includes a casing 41A and a plurality of components housed within the casing 41A. These components include a first exhaust fan 42A, a first exhaust detection unit 43A, and a first exhaust controller 44A. The first exhaust fan 42A is, for example, a centrifugal fan whose fan speed can be controlled. The first exhaust detection unit 43A is, for example, an airflow sensor for detecting airflow volume, or a sensor for detecting an equivalent amount of airflow volume. Therefore, if the first exhaust controller 44A has a fan speed counting function, the first exhaust controller 44A also functions as the first exhaust detection unit 43A.

[0102] The first exhaust controller 44A is, for example, a control module including a circuit board and integrated circuits such as a CPU and memory mounted on the circuit board. The integrated circuits may include at least one of FPGAs and ASICs. The first exhaust controller 44A is capable of performing communication control with other controllers and sensors in accordance with a predetermined communication standard, and performing predetermined information processing such as controlling the fan speed of the first exhaust fan 42A so that the airflow reaches a target value.

[0103] The second exhaust unit 40B includes a casing 41B and a plurality of components housed within the casing 41B. These components include a second exhaust fan 42B, a second exhaust detection unit 43B, and a second exhaust controller 44B. The second exhaust fan 42B is, for example, a centrifugal fan whose fan speed can be controlled. The second exhaust detection unit 43B is, for example, an airflow sensor for detecting airflow volume, or a sensor for detecting an equivalent amount of airflow volume. Therefore, if the second exhaust controller 44B has a fan speed counting function, the second exhaust controller 44B also functions as the second exhaust detection unit 43B.

[0104] The second exhaust controller 44B is, for example, a control module including a circuit board and integrated circuits such as a CPU and memory mounted on the circuit board. The integrated circuits may include at least one of FPGAs and ASICs. The second exhaust controller 44B is capable of performing predetermined information processing, such as communication control with other controllers and sensors in accordance with a predetermined communication standard, and control of the fan speed of the second exhaust fan 42B so that the airflow reaches a target value.

[0105] [Air supply and exhaust ducts for ventilation systems] In the ceiling space of the target spaces RM1 and RM2, the intake port of the casing 11 is connected to the outdoor air supply port by the duct d1. In the ceiling space of the target spaces RM1 and RM2, the intake ports of casings 21A and 21B are airtightly connected to the outlet ports of casing 11 by duct d2, which consists of branch pipes.

[0106] The outlet of the casing 21A is exposed from the ceiling surface to the target space RM1. Therefore, the first supply fan 22A is a fan that supplies outdoor air to the target space RM1. The outlet of casing 21B is exposed from the ceiling surface into the target space RM2. Therefore, the second supply fan 22B is a fan that supplies outdoor air to the target space RM2.

[0107] Furthermore, the air passage formed by duct d1, casing 11, duct d2, and casings 21A and 21B connects the outdoors and indoors, and constitutes an "air supply passage" in which the first heat exchanger 12, the first air supply fan 22A, and the second air supply fan 22B are located.

[0108] Under the floor of the target space RM1, the intake port of casing 41A is connected to the supply port of the target space RM1. The outlet port of casing 41A is airtightly connected to the intake port of casing 31 by duct d3. In the underfloor space RM2, the intake port of casing 41B is connected to the air supply port of RM2. The outlet port of casing 41B is airtightly connected to the intake port of casing 31 by duct d4. Note that ducts d3 and d4 may be branch ducts such as duct d2.

[0109] Within the wall of the target space RM1, the intake port of the casing 31 is connected to an exhaust port outdoors via duct d5. Therefore, the first exhaust fan 42A is a fan that discharges air from the target space RM1 to the outside, and the second exhaust fan 42B is a fan that discharges air from the target space RM2 to the outside.

[0110] Furthermore, the air passage formed by casing 41A, duct d3, casing 41B, duct d4, casing 31, and duct d5 connects the outdoors and indoors, and constitutes an "exhaust air passage" in which the second heat exchanger 32, the first exhaust fan 42A, and the second exhaust fan 42B are located.

[0111] In the ventilation system 4 of the second embodiment, the first supply air temperature sensor 24A is a sensor that detects the temperature of the supply air SA relative to the target space RM1, and the second supply air temperature sensor 24B is a sensor that detects the temperature of the supply air SA relative to the target space RM2.

[0112] In the ventilation system 1 shown in Figure 6, the heat exchange unit 10 and the supply air units 20A and 20B may be integrated units housed in the same casing. Similarly, the heat exchange unit 30 and the exhaust units 40A and 40B may be integrated units housed in the same casing.

[0113] [Ventilation system control system] Figure 7 is a block diagram showing an example of the control system for the ventilation system 4. As shown in Figure 7, the first and second input devices 70A and 70B are each capable of transmitting SI to the main controller 55. The meanings of the parameters included in Figure 7 (excluding those included in Figure 2) are as follows.

[0114] TS1: Detection result of the first supply air temperature sensor 24A (supply air temperature of the first supply air fan) TS2: Detection result of the second supply air temperature sensor 24B (supply air temperature of the second supply air fan) PR1: Detection result of the first pressure sensor 80A (atmospheric pressure in the target space RM1) PR2: Detection result of the second atmospheric pressure sensor 80B (atmospheric pressure in the target space RM2)

[0115] AF11: Airflow from the first supply fan 22A (First supply airflow) AF12: Airflow from the first exhaust fan 42A (First exhaust airflow) AF21: Airflow from the second supply fan 22B (second supply airflow) AF22: Airflow from the second exhaust fan 42B (second exhaust airflow)

[0116] TV11: Target value for the airflow volume (first air supply airflow) blown out by the first supply fan 22A. TV12: Target value for the airflow volume (first exhaust airflow volume) blown out by the first exhaust fan 42A. TV21: Target value of the airflow volume (second air supply airflow volume) blown out by the second supply fan 22B. TV22: Target value for the airflow volume (second exhaust airflow volume) blown out by the second exhaust fan 42B.

[0117] As shown in Figure 7, the control unit CU comprises a main controller 55, a first supply air controller 25A, a second supply air controller 25B, a first exhaust controller 44A, and a second exhaust controller 44B. The main controller 55 is connected to the first and second input devices 70A and 70B, which can transmit SIs to the main controller 55. The main controller 55 records the received SIs in its memory.

[0118] The main controller 55 is connected to the first and second supply air temperature sensors 24A and 24B, and receives TS1 and TS2 from these sensors. When the first supply air temperature sensor 24A is connected to the first supply air controller 25A, the controller 25A may be used as a relay node to transmit TS1 to the main controller 55. When the second supply air temperature sensor 24B is connected to the second supply air controller 25B, the controller 25B may be used as a relay node to transmit TS2 to the main controller 55.

[0119] The main controller 55 is connected to the first air supply controller 25A, the second air supply controller 25B, the first exhaust controller 44A, and the first exhaust controller 44B.

[0120] If the main controller 55 determines TV 11, it transmits the determined TV 11 to the first air supply controller 25A. If the main controller 55 determines TV12, it transmits the determined TV12 to the first exhaust controller 44A.

[0121] If the main controller 55 determines TV21, it transmits the determined TV21 to the second air supply controller 25B. If the main controller 55 determines TV22, it transmits the determined TV22 to the second exhaust controller 44B.

[0122] The first air supply controller 25A is connected to the first air supply fan 22A, the first air supply detection unit 23A, and the first atmospheric pressure sensor 80A. The first air supply controller 25A forwards PR1 received from the first pressure sensor 80A to the main controller 55. If the first pressure sensor 80A is connected to the main controller 55, PR1 is sent directly to the main controller 55.

[0123] If the first air supply controller 25A is an airflow sensor, it sets the detection result received from the detection unit 23A to AF11. The first air supply controller 25A calculates AF11 from the detection result received from the detection unit 23A if the first air supply detection unit 23A is a sensor for the amount of airflow equivalent. The first air supply controller 25A may also use the airflow calculated from the fan rotation speed it counts as AF11. When the first air supply controller 25A receives TV11, it calculates the fan speed based on TV11 and AF11 and outputs the calculated speed to the first air supply fan 22A.

[0124] The first exhaust controller 44A is connected to the first exhaust fan 42A and the first exhaust detection unit 43A.

[0125] If the first exhaust detection unit 43A is an airflow sensor, the first exhaust controller 44A sets the detection result received from the detection unit 43A as AF12. If the first exhaust detection unit 43A is a sensor for airflow equivalent volume, the first exhaust controller 44A calculates AF12 from the detection result received from the detection unit 43A. The first exhaust controller 44A may also use the airflow calculated from the fan rotation speed it counts as AF12. When the first exhaust controller 44A receives TV12, it calculates the fan speed based on TV12 and AF12 and outputs the calculated speed to the first exhaust fan 42A.

[0126] The second air supply controller 25B is connected to the second air supply fan 22B, the second air supply detection unit 23B, and the second atmospheric pressure sensor 80B. The second air supply controller 25B forwards PR2 received from the second atmospheric pressure sensor 80B to the main controller 55. If the second atmospheric pressure sensor 80B is connected to the main controller 55, PR2 is sent directly to the main controller 55.

[0127] If the second air supply controller 25B is an airflow sensor, it sets the detection result received from the detection unit 23B as AF21. The second air supply controller 25B calculates AF21 from the detection result received from the detection unit 23B if the second air supply detection unit 23B is a sensor for airflow equivalent volume. The second air supply controller 25B may also use the airflow volume calculated from the fan rotation speed it counts as AF21. When the second air supply controller 25B receives TV21, it calculates the fan speed based on TV21 and AF21 and outputs the calculated speed to the second air supply fan 22B.

[0128] The second exhaust controller 44B is connected to the second exhaust fan 42B and the second exhaust detection unit 43B.

[0129] If the second exhaust detection unit 43B is an airflow sensor, the second exhaust controller 44B sets the detection result received from the detection unit 43B as AF22. The second exhaust controller 44B calculates AF22 from the detection result received from the detection unit 43B if the second exhaust detection unit 43B is a sensor for airflow equivalent. The second exhaust controller 44B may also use the airflow calculated from the fan rotation speed it counts as AF22. When the second exhaust controller 44B receives TV22, it calculates the fan speed based on TV22 and AF22 and outputs the calculated speed to the second exhaust fan 42B.

[0130] [Information processing of the main controller] Figure 8 is a flowchart showing an example of information processing by the main controller 55. As shown in Figure 8, after startup, the main controller 55 reads the latest configuration information SI from memory (step ST71). Next, the main controller 55 acquires the temperature detection results TS1, TS2, TO, and TR (step ST72), and acquires the indoor atmospheric pressure detection results PR1 and PR2 in each target space RM1 and RM2 (step ST73).

[0131] Next, the main controller 55 performs the determination process for the target values ​​of each airflow, TV11, TV12, TV21, and TV22 (step ST74). Details of this determination process (Figure 9) will be described later. Next, the main controller 55 performs a calculation process for CQ, which is the control amount for the refrigerant circuit 60 (step ST75). This calculation process calculates CQ based on TV11, TV12, TV21, and TV22 determined in the current control cycle.

[0132] For example, the main controller 55 calculates the temperature control load required to bring the supply air SA of the target spaces RM1 and RM2 to the set temperature Sit specified by each input device 70A and 70B, from the TV11, TV12, TV21 and TV22 determined in the current control cycle, and the current TS1, TS2, TO and TR, and determines the control amount CQ of the refrigerant circuit 60 based on the calculated temperature control load.

[0133] Next, the main controller 55 transmits TV11, TV12, TV21, and TV22 to the respective controllers 25A, 44A, 25B, and 44B (step ST76). Specifically, the main controller 55 transmits TV11 to the first supply air controller 25A and TV12 to the first exhaust air controller 44A. The main controller 55 also transmits TV21 to the second supply air controller 25B and TV22 to the second exhaust air controller 44B.

[0134] Next, the main controller 55 controls the refrigerant circuit 60 according to the CQ determined in step ST75 (step ST77), and determines whether a predetermined control cycle (e.g., 30 seconds) has elapsed (step ST78). If the result of step ST78 is positive, the main controller 55 returns the process to before step ST71.

[0135] If the result of step ST78 is negative, the main controller 55 determines whether or not a termination command has been received from the input device 70 (step ST79). If the result of step ST79 is negative, the main controller 55 returns the process to before ST78. If the result of step ST79 is positive, the main controller 55 terminates the process.

[0136] [Process for determining target values ​​for supply and exhaust airflow rates] Figure 9 is a flowchart showing an example of the process for determining target values ​​for supply and exhaust airflow rates (step ST74 in Figure 8). In Figure 9, the suffix "k" is the identification number for the target spaces RM1 and RM2. It is also the identification number for the input devices 70A and 70B. k=1 means target space RM1, and k=2 means target space RM2.

[0137] Therefore, the main controller 55 performs a decision process for the SI of the first input device 70A with k=1 in Figure 9, and performs a decision process for the SI of the second input device 70B with k=2 in Figure 9. Here again, the types of supply airflow rates that can be specified in SIc are assumed to be four types: light breeze, weak breeze, medium breeze, and strong breeze. Furthermore, the memory of the main controller 55 shall hold a reference table that defines the correspondence between the type of supply airflow rate and the target value TVk1 of the supply airflow rate.

[0138] As shown in Figure 9, the main controller 55 determines TVk1 from the type of supply airflow rate included in SIc (step ST91). Specifically, the main controller 55 reads the target value of the supply airflow rate corresponding to the type specified in SIc from the reference table, and sets the read target value as TVk1.

[0139] Next, the main controller 55 determines whether or not an SIa input has been received (step ST92). This determination can be made by checking whether or not SIa is recorded in memory. If the result of step ST92 is negative, the main controller 55 determines whether or not an SIb input was received (step ST93). This determination can be made by checking whether or not the SIb is recorded in memory.

[0140] If the result of step ST93 is negative, the main controller 55 sets TVk2 to the same value as TVk1 (step ST95). Thus, when there are no inputs for SIa and SIb, the main controller 55 determines target values ​​TVk1 and TVk2 so that the supply airflow rate and exhaust airflow rate are balanced. If the result of step ST93 is positive, the main controller 55 calculates TVk2 from the determined TVk1 and the set pressure specified by SIb.

[0141] For example, the main controller 55 has pre-stored a relationship between the atmospheric pressure (e.g., static pressure) of the target spaces RM1 and RM2, the airflow path length of the ventilation system 4, the supply airflow rate, and the exhaust airflow rate. The main controller 55 calculates TVk2 by applying the set atmospheric pressure, TVk1, and the airflow path length of system 1 to this relationship. If the determination result in step ST92 is affirmative, the main controller 55 determines whether the type specified by SIa is positive pressure or negative pressure (step ST94).

[0142] If the determination result in step ST94 is "positive pressure", the main controller 55 determines an appropriate TVk2 under the condition of TVk1 > TVk2 (step ST97). For example, the main controller 55 calculates TVk2 according to the following calculation formula. Note that ΔTVa is a preset air volume difference value for positive pressure according to the volume of the target spaces RM1 and RM2, etc. TVk2 = TVk1 - ΔTVa

[0143] If the determination result in step ST94 is "negative pressure", the main controller 55 determines an appropriate TVk2 under the condition of TVk1 < TVk2 (step ST98). For example, the main controller 55 calculates TVk2 according to the following calculation formula. Note that ΔTVb is a preset air volume difference value for negative pressure according to the volume of the target spaces RM1 and RM2, etc. TVk2 = TVk1 + ΔTVb

[0144] [Information Processing of Air Supply and Exhaust Controllers] FIG. 10 is a flowchart showing an example of information processing of the air supply and exhaust controllers 25A, 44A, 25B, and 44B. In FIG. 10, the suffix "k" is the identification number of the target spaces RM1 and RM2. It is also the identification number of the input devices 70A and 70B. k = 1 means the target space RM1, and k = 2 means the target space RM2. The suffix "j" is the identification number representing air supply or exhaust. j = 1 means air supply, and j = 2 means exhaust.

[0145] Therefore, FIG. 10 represents the information processing of the first air supply controller 25A when k = 1 and j = 1, and represents the information processing of the first exhaust controller 44A when k = 1 and j = 2. Similarly, FIG. 10 shows the information processing of the second air supply controller 25B when k = 2 and j = 1, and shows the information processing of the second exhaust controller 44B when k = 2 and j = 2.

[0146] As shown in FIG. 10, each of the controllers 25A, 44A, 25B, and 44B determines whether it has received TVkj from the main controller 55 after startup (step ST101). If received, it acquires AFkj from the detection results of the detection units 23A, 43A, 23B, and 43B of its own unit (step ST102).

[0147] Next, each of the controllers 25A, 44A, 25B, and 44B compares the magnitudes of AFkj and TVkj (step ST103), and executes the following processing according to the comparison result. That is, when AFkj < TVkj, each of the controllers 25A, 44A, 25B, and 44B increases the rotation speed of the fans 22A, 42A, 22B, and 42B of its own unit by a predetermined amount (step ST104). When AFkj = TVkj, it maintains the rotation speed (step ST105). When AFkj > TVkj, it decreases the rotation speed by a predetermined amount (step ST106).

[0148] In this way, the air supply and exhaust controllers 25A and 44A for the target space RM1 and the air supply and exhaust controllers 25B and 44B for the target space RM2 autonomously adjust the rotation speed of the fans 22A, 42A, 22B, and 42B of their own units based on TVkj received from the main controller 55 and AFkj detectable by the detection units 23A, 43A, 23B, and 43B of their own units.

[0149] <Operational Effects of the Second Embodiment> (6) According to the ventilation system 4 of the second embodiment, the control unit CU (specifically, each of the controllers 25A, 44A, 25B, and 44B) executes the following first air supply control, first exhaust control, second air supply control, and second exhaust control. Therefore, by appropriately setting the target values ​​TV11, TV12, TV21, and TV22 for the first supply airflow rate AF11, the first exhaust airflow rate AF12, the second supply airflow rate AF21, and the second exhaust airflow rate AF22, the target spaces RM1 and RM2 can be set to positive or negative pressure, respectively. Thus, heat can be recovered from the return air RA while setting the target spaces RM1 and RM2 to positive or negative pressure.

[0150] First supply air control: Control that adjusts the rotation speed of the first supply air fan 22A so that the first supply air volume AF11 becomes the target value TV11. First exhaust control: Control that adjusts the rotation speed of the first exhaust fan 42A so that the first exhaust airflow AF12 becomes the target value TV12.

[0151] Second air supply control: Control that adjusts the rotation speed of the second air supply fan 22B so that the second air supply volume AF21 becomes the target value TV21. Second exhaust control: Control that adjusts the rotation speed of the second exhaust fan 42B so that the second exhaust airflow AF22 reaches the target value TV22.

[0152] (7) According to the ventilation system 4 of the second embodiment, the control unit CU (specifically, the main controller 55) sets the target value TV11 of the first supply airflow rate higher than the target value TV12 of the first exhaust airflow rate when the first atmospheric pressure condition (SIa input to the first input device 70A) is positive pressure, and sets the target value TV12 of the first exhaust airflow rate higher than the target value TV11 of the first supply airflow rate when the first atmospheric pressure condition is negative pressure, so that the target space RM1 can be set to positive or negative pressure according to the atmospheric pressure condition set by the user.

[0153] Furthermore, the control unit CU (specifically, the main controller 55) sets the target value TV21 of the second supply airflow rate higher than the target value TV22 of the second exhaust airflow rate when the second atmospheric pressure condition (SIa input to the second input device 70B) is positive pressure, and sets the target value TV22 of the second exhaust airflow rate higher than the target value TV21 of the second supply airflow rate when the second atmospheric pressure condition is negative pressure. Thus, the target space RM2 can be set to positive or negative pressure according to the atmospheric pressure condition specified by the user.

[0154] (8) According to the ventilation system 4 of the second embodiment, the control unit CU (specifically, the main controller 55) determines the target value TV11 for the first supply air volume and the target value TV12 for the first exhaust air volume so that the indoor air pressure becomes the set air pressure specified by the first air pressure information (SIb input to the first input device 70A), so that the air pressure in the target space RM1 can be set to the set air pressure specified by the user.

[0155] Furthermore, the control unit CU (specifically, the main controller 55) determines the target value TV21 for the second supply airflow and the target value TV22 for the second exhaust airflow so that the indoor air pressure becomes the set air pressure specified by the second air pressure information (SIb input to the second input device 70B). Thus, the air pressure in the target space RM2 can be set to the set air pressure specified by the user. Therefore, by specifying different pressure values ​​for target space RM1 and target space RM2, ventilation can be performed that creates a pressure difference between the rooms.

[0156] (9) The ventilation system 4 of the second embodiment has the following effects: In other words, if the input devices are remote control devices 70A and 70B installed in the control room, there is the advantage that the operation of setting the atmospheric pressure in the target spaces RM1 and RM2 can be limited to administrator privileges. Furthermore, if remote control device 70A is installed in target space RM1 and remote control device 70B is installed in target space RM2, there is the advantage that users in each target space RM1 and RM2 can easily perform the pressure setting procedure.

[0157] (10) According to the ventilation system 4 of the second embodiment, the control unit CU (specifically, the main controller 55) determines the control amount CQ of the refrigerant circuit 60 based on the target value TV11 of the first supply airflow rate, the target value TV12 of the first exhaust airflow rate, the target value TV21 of the second supply airflow rate, and the target value TV22 of the second exhaust airflow rate. For example, the refrigerant circuit 60 can be controlled with an appropriate amount of heat recovery while maintaining a positive or negative pressure state in the target spaces RM1 and RM2.

[0158] <First variation> In the above embodiment, we have illustrated an airflow configuration where M=N=1, where M is the number of fans on the supply side and N is the number of fans on the exhaust side for one room RM, RM1, RM2. However, both the number of fans M and the number of fans N may be two or more. Furthermore, the number of fans M and the number of fans N may be different.

[0159] If there are two or more fans (number M), the total airflow from the M fans should be used as the supply airflow for one room, RM1, and RM2. Furthermore, if the number of fans N is two or more, the total airflow from the N fans can be used as the exhaust airflow from a single room, RM1, or RM2.

[0160] <Second variation> In the above-described embodiment, the intake unit 20 and exhaust unit 30 may be used without a controller, and the control for adjusting the fan speed may also be managed by the main controller 55.

[0161] However, by employing the air supply unit 20 and exhaust unit 30 equipped with controllers as described in the above embodiment, the control is distributed and executed by the main controller 55 and the controllers of each unit, thereby reducing the processing load on the main controller 55 and allowing the use of inexpensive control modules. Furthermore, in the above-described embodiment, the controllers 25, 25A, and 25B relay the detection results of some measuring devices (e.g., the pressure sensor 80), so the increase in signal lines can be suppressed as much as possible.

[0162] <Other> This disclosure is not limited to the above examples and is intended to include all modifications within the meaning and scope of the claims, as shown in the claims. [Explanation of Symbols]

[0163] 1. Ventilation System 12 1st heat exchanger 20 Air supply units 20A First Air Supply Unit 20B Second Air Supply Unit 22 Intake fan 22A No. 1 Intake Fan 22B Second Intake Fan 23 Air supply detection unit 23A First Air Supply Detection Unit 23B Second Air Supply Detection Unit 24. Intake air temperature sensor 24A First supply air temperature sensor 24B Second supply air temperature sensor 25. Air Intake Controller 25A First Air Supply Controller 25B Second Air Intake Controller 32 Second heat exchanger 33. Return air temperature sensor 40 Exhaust Unit 40A First Exhaust Unit 40B Second Exhaust Unit 42 Exhaust fan 42A First Exhaust Fan 42B Second Exhaust Fan 43 Exhaust detection unit 43A First exhaust detection unit 43B Second exhaust detection unit 44 Exhaust Controller 44A First Exhaust Controller 44B Second Exhaust Controller 52 Compressor 53 Four-way valve 54 Expansion valve 55 Main Controller 60 Refrigerant Circuit 61 Refrigerant piping 70 Input device (remote control device) 70A First Input Device (Remote Control Device) 70B Second Input Device (Remote Control Device) 80 barometric pressure sensor 80A No. 1 pressure sensor 80B Second barometric pressure sensor RM Target space (room) RM1 Target space (First room) RM2 Target Space (Second Room) CU Control Unit AF1 Intake air volume AF2 Exhaust airflow TV1 Target value for supply airflow TV2 Exhaust airflow target value AF11 First supply air volume AF12 First exhaust airflow AF21 Second supply airflow AF22 Second exhaust airflow TV11 Target value for the first supply airflow rate TV12 Target value for the first exhaust air volume TV21 Target value for the second supply airflow rate TV22 Target value for exhaust airflow volume 2 CQ (Cold Quotient) - Control amount for the refrigerant circuit SIa barometric pressure conditions SIb barometric pressure information

Claims

1. A refrigerant circuit (60) that circulates refrigerant to the compressor (52), the first heat exchanger (12), and the second heat exchanger (32), An air intake fan (22) that supplies outdoor air to the indoors, An exhaust fan (42) that expels indoor air to the outside, A supply air passage connecting the outdoors and indoors, in which the first heat exchanger (12) and the supply air fan (22) are arranged, An exhaust air passage connecting the outdoors and indoors, in which the second heat exchanger (32) and the exhaust fan (42) are arranged, The air supply detection unit (23) detects the amount of air supply (AF1) blown out by the air supply fan (22), An exhaust detection unit (43) for detecting the amount of exhaust air (AF2) blown out by the exhaust fan (42), It includes a control unit (CU), The refrigerant circuit (60) further comprises a four-way valve (53) and an expansion valve (54), The control unit (CU) is Air supply control that adjusts the rotation speed of the air supply fan (22) so that the air supply volume (AF1) becomes a target value (TV1), Exhaust control is performed to adjust the rotation speed of the exhaust fan (42) so that the exhaust air volume (AF2) becomes a target value (TV2). A ventilation system (1) that determines a control quantity (CQ) for at least one of the compressor (52), the four-way valve (53), and the expansion valve (54) based on the target value of the supply air volume (TV1) and the target value of the exhaust air volume (TV2).

2. The ventilation system (1) is The system further includes an input device that allows the user to input settings information, including atmospheric pressure conditions representing positive or negative pressure indoors. The control unit (CU) is If the aforementioned atmospheric pressure condition is positive pressure, the target value of the supply airflow rate (TV1) is set higher than the target value of the exhaust airflow rate (TV2). The ventilation system (1) according to claim 1, wherein if the atmospheric pressure condition is negative pressure, the target value of the exhaust air volume (TV2) is set higher than the target value of the supply air volume (TV1).

3. The ventilation system (1) is It is further equipped with a pressure sensor (80) for detecting indoor air pressure, The setting information that the user can input into the input device includes: It includes pressure information to specify the level of indoor pressure settings. The control unit (CU) is The ventilation system (1) according to claim 2, wherein the target value of the supply air volume (TV1) and the target value of the exhaust air volume (TV2) are determined so that the indoor air pressure becomes the set air pressure specified in the air pressure information.

4. The aforementioned input device is The ventilation system (1) according to claim 2 or 3, wherein the remote control device (70) is installed in the control room or the room to be ventilated (RM) and is capable of wired or wireless communication.

5. A refrigerant circuit (60) for circulating refrigerant to a compressor (52), a first heat exchanger (12), and a second heat exchanger (32), An air intake fan (22) that supplies outdoor air to the indoors, An exhaust fan (42) that expels indoor air to the outside, A supply air passage connecting the outdoors and indoors, in which the first heat exchanger (12) and the supply air fan (22) are arranged, An exhaust air passage connecting the outdoors and indoors, in which the second heat exchanger (32) and the exhaust fan (42) are arranged, The air supply detection unit (23) detects the amount of air supply (AF1) blown out by the air supply fan (22), An exhaust detection unit (43) for detecting the amount of exhaust air (AF2) blown out by the exhaust fan (42), It includes a control unit (CU), The control unit (CU) is Air supply control that adjusts the rotation speed of the air supply fan (22) so that the air supply volume (AF1) becomes a target value (TV1), Exhaust control is performed to adjust the rotation speed of the exhaust fan (42) so that the exhaust air volume (AF2) becomes a target value (TV2). The aforementioned intake fan (22) A first air supply fan (22A) that supplies outdoor air to the first indoor room (RM1), Includes a second air supply fan (22B) that supplies outdoor air to a second indoor room (RM2). The exhaust fan (42) is A first exhaust fan (42A) discharges the air from the first room (RM1) to the outside, The system includes a second exhaust fan (42B) for discharging the air from the second room (RM2) to the outside, The aforementioned air supply detection unit (23) A first air supply detection unit (23A) for detecting the first air supply air volume (AF11) blown out by the first air supply fan (22A), The system includes a second supply air detection unit (23B) for detecting the second supply air volume (AF21) blown out by the second supply air fan (22B), The exhaust detection unit (43) is A first exhaust detection unit (43A) for detecting the first exhaust air volume (AF12) blown out by the first exhaust fan (42A), The system includes a second exhaust detection unit (43B) for detecting the second exhaust air volume (AF22) blown out by the second exhaust fan (42B), The aforementioned air supply control is, A first air supply control system adjusts the rotation speed of the first air supply fan (22A) so that the first air supply volume (AF11) becomes a target value (TV11), The system includes a second air supply control that adjusts the rotation speed of the second air supply fan (22B) so that the second air supply volume (AF21) becomes a target value (TV21), The exhaust control described above is A first exhaust control system adjusts the rotation speed of the first exhaust fan (42A) so that the first exhaust air volume (AF12) becomes a target value (TV12), A ventilation system (4) including a second exhaust control that adjusts the rotation speed of the second exhaust fan (42B) so that the second exhaust air volume (AF22) becomes a target value (TV22).

6. The ventilation system (4) is The user can input the following configuration information: A first atmospheric pressure condition representing the positive or negative pressure of the first room (RM1), and The system further includes an input device that includes a second atmospheric pressure condition representing the positive or negative pressure of the second room (RM2), The control unit (CU) is If the first atmospheric pressure condition is positive pressure, the target value of the first supply airflow rate (TV11) is set higher than the target value of the first exhaust airflow rate (TV12). If the first atmospheric pressure condition is negative pressure, the target value of the first exhaust airflow (TV12) is set higher than the target value of the first supply airflow (TV11). If the second atmospheric pressure condition is positive pressure, the target value of the second supply airflow rate (TV21) is set higher than the target value of the second exhaust airflow rate (TV22). The ventilation system (4) according to claim 5, wherein if the second atmospheric pressure condition is negative pressure, the target value of the second exhaust airflow (TV22) is set higher than the target value of the second supply airflow (TV21).

7. The ventilation system (4) is A first pressure sensor (80A) for detecting the pressure in the first room (RM1), The system further includes a second pressure sensor (80B) for detecting the pressure in the second chamber (RM2), The setting information that the user can input into the input device includes: First atmospheric pressure information for specifying the amount of pressure set in the first room (RM1), This includes second atmospheric pressure information for specifying the amount of pressure set in the second room (RM2), The control unit (CU) is The target value (TV11) of the first supply airflow rate and the target value (TV12) of the first exhaust airflow rate are determined so that the atmospheric pressure in the first room (RM1) becomes the set atmospheric pressure specified in the first atmospheric pressure information. The ventilation system (4) according to claim 6, wherein the target value of the second supply airflow rate (RV21) and the target value of the second exhaust airflow rate (TV22) are determined so that the air pressure in the second room (RM2) becomes the set air pressure specified by the second air pressure information.

8. The aforementioned input device is The ventilation system (4) according to claim 7, wherein the remote control devices (70A, 70B) are wired or wirelessly operated, and are installed in the control room or the first room (RM1) and the second room (RM2).

9. The refrigerant circuit (60) further comprises a four-way valve (53) and an expansion valve (54), The control unit (CU) is A ventilation system (4) according to any one of claims 5 to 8, wherein a control amount (CQ) of at least one of the compressor (52), the four-way valve (53), and the expansion valve (54) is determined based on the target value of the first supply air volume (TV11), the target value of the first exhaust air volume (TV12), the target value of the second supply air volume (TV21), and the target value of the second exhaust air volume (TV22).

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