Ventilation device

Abstract

To provide a technique capable of reducing electric power consumption of a ventilation device.SOLUTION: In a ventilation device, an air supply air course 10 is for transporting air sucked from an outdoor side through an outdoor side air supply port to a predetermined indoor space through an indoor side air supply port. An air supply air blower 6 transports outdoor air to the predetermined space via the air supply air course 10 as a supply air current 11. An air exhaust air course 9 is for transporting air sucked from the predetermined space through an indoor side air exhaust port to the outdoor side through an outdoor side air exhaust port. An air exhaust air blower 3 transports air in the predetermined space to the outdoor side via the air exhaust air course 9 as an exhaust air current 12. A determination section determines an opening / closing state of a window in the predetermined space. A control section controls the air supply air blower 6 and the air exhaust air blower 3. When the determination section determines that the window is open, the control section lowers an air blowing amount of at least one of the air supply air blower 6 and the air exhaust air blower 3, compared to when closing of the window is determined.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to ventilation devices. [Background technology]

[0002] Heat exchange ventilation systems are mainly used in 24-hour ventilation systems for highly airtight and highly insulated houses. The advantage of heat exchange ventilation systems is that they can bring in outside air at a temperature close to that of the room, thereby reducing heating and cooling costs. For example, Patent Document 1 discloses a heat exchange ventilation device that ventilates while exchanging heat between air from inside the room and air from outside. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-197317 Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, ventilation equipment used in 24-hour ventilation systems operates continuously 24 hours a day, 365 days a year, so it is desirable to reduce the amount of power consumed by ventilation equipment.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a technology that can reduce the amount of power consumed by a ventilation device. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the present invention provides a ventilation device that includes an intake air duct for transporting air drawn in from outdoors through an outdoor air intake port to a predetermined indoor space through an indoor air intake port, an intake fan that transports the outdoor air as an intake airflow through the intake air duct to the predetermined space, an exhaust air duct for transporting air drawn in from the predetermined space through an indoor exhaust port to outdoors through an outdoor exhaust port, an exhaust fan that transports the air in the predetermined space to outdoors as an exhaust airflow through the exhaust air duct, a determination unit that determines whether a window in the predetermined space is open or closed, and a control unit that controls the intake fan and the exhaust fan. When the determination unit determines that the window is open, the control unit reduces the airflow rate of at least one of the intake fan and the exhaust fan compared to when the window is determined to be closed.

[0007] Any combination of the above components and conversion of the expressions of the present disclosure into methods, devices, systems, etc. are also valid aspects of the present disclosure. [Effects of the Invention]

[0008] According to the present disclosure, a technique that can reduce the amount of power consumed by a ventilation device can be provided. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a plan view schematically showing the configuration of a heat exchange type ventilation device according to an embodiment. [Figure 2] 2 is a schematic functional block diagram of the control device and peripheral configuration of FIG. 1. FIG. [Figure 3] 2 is a flowchart showing the process of the heat exchange type ventilation device of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the accompanying drawings. In the embodiments and modified examples, identical or equivalent components and members are designated by the same reference numerals, and redundant explanations will be omitted where appropriate. Furthermore, the dimensions of the members in each drawing are enlarged or reduced as appropriate for ease of understanding. Furthermore, some members that are not important for explaining the embodiments will be omitted from the drawings.

[0011] FIG. 1 is a plan view showing the schematic configuration of a heat exchanger type ventilation device 1 according to an embodiment. The heat exchanger type ventilation device 1 can be installed in the ceiling, in a side wall, or under the floor of a building, and is a ventilation device that supplies and exhausts air to and from an indoor space. The heat exchanger type ventilation device 1 is a ventilation device that has a function of exchanging heat when supplying and exhausting air. In the embodiment, a heat exchanger type ventilation device will be used as an example of a ventilation device for explanation, but it does not have to have a function of exchanging heat.

[0012] The heat exchanger ventilation device 1 performs ventilation while exchanging heat between air exhausted from a predetermined indoor space to the outdoors (exhaust air flow 12, described below) and air supplied from the outdoors to a predetermined indoor space (intake air flow 11, described below). For example, in the summer in Japan, the heat exchanger ventilation device 1 performs ventilation while transferring heat from the intake air flow 11 to the exhaust air flow 12, thereby suppressing unnecessary inflow of heat. In addition, in the winter in Japan, the heat exchanger ventilation device 1 performs ventilation while transferring heat from the exhaust air flow 12 to the intake air flow 11, thereby suppressing unnecessary outflow of heat.

[0013] Here, exhaust air flow 12 is a flow of air that is discharged from a predetermined indoor space to the outdoors. The exhaust air flow 12 is transported from the predetermined indoor space to the heat exchange type ventilation device 1. After the exhaust air flow 12 exchanges heat with the intake air flow 11 by the heat exchange type ventilation device 1, the exhaust air flow 12 is discharged from the heat exchange type ventilation device 1 to the outdoors.

[0014] The intake air flow 11 is a flow of air supplied from outdoors to a specified indoor space. The intake air flow 11 is transported from outdoors to the heat exchange type ventilation device 1. The intake air flow 11 exchanges heat with the exhaust air flow 12 by the heat exchange type ventilation device 1, and is then supplied to the specified indoor space.

[0015] The heat exchange type ventilation device 1 is a device that performs ventilation while exchanging heat between air RA (exhaust air flow 12) in a predetermined indoor space and outdoor air OA (intake air flow 11).

[0016] The heat exchange type ventilation device 1 includes an inside air port 4, an exhaust port 5, an outside air port 7, an intake port 8, a heat exchange element 2, an exhaust fan 3, an intake fan 6, a differential pressure detection unit 13, a control device 14, and an operating device 16.

[0017] The internal air vent 4 is an intake port for taking air RA (exhaust air flow 12) from a specified indoor space into the heat exchange type ventilation device 1. The internal air vent 4 is connected to a duct (not shown) so as to communicate with a specified indoor space such as a room. The internal air vent 4 forms part of the exhaust air duct 9. The internal air vent 4 can also be said to be an indoor exhaust port.

[0018] The exhaust port 5 is an outlet for discharging the exhaust air flow 12 from the heat exchange type ventilation device 1 to the outdoors as exhaust air EA. The exhaust port 5 may be connected to a duct (not shown) so as to be in communication with the outdoors. The exhaust port 5 constitutes a part of the exhaust air duct 9. The exhaust port 5 can also be called an outdoor exhaust port.

[0019] The outside air vent 7 is an intake port for taking outdoor air OA (supply air flow 11) into the heat exchange type ventilation device 1. The outside air vent 7 may be connected to the outdoors by being connected to a duct (not shown). The outside air vent 7 forms part of the supply air duct 10. The outside air vent 7 can also be called an outdoor air intake vent.

[0020] The air intake port 8 is a discharge port for discharging the intake air flow 11 as intake air SA from the heat exchange type ventilation device 1 to a predetermined space indoors. The air intake port 8 is connected to a duct (not shown) so as to communicate with a predetermined space indoors, such as a room inside the building. The air intake port 8 constitutes a part of the intake air duct 10. The air intake port 8 can also be called an indoor-side air intake port.

[0021] The heat exchange element 2 is a member for exchanging heat between the exhaust air flow 12 and the intake air flow 11. The heat exchange may be sensible heat exchange, which exchanges temperature between the exhaust air flow 12 and the intake air flow 11, or total heat exchange, which exchanges both sensible heat and latent heat, which exchanges humidity between the exhaust air flow 12 and the intake air flow 11.

[0022] The heat exchange element 2 is a total heat exchange element formed from heat transfer paper (heat transfer plate) based on cellulose fiber. However, the material is not limited to this. The heat transfer plate constituting the heat exchange element 2 can be, for example, a moisture-permeable resin film based on polyurethane or polyethylene terephthalate, or a paper material based on cellulose fiber, ceramic fiber, or glass fiber. The heat transfer plate constituting the heat exchange element 2 can also be a thin sheet with heat conductivity that is impermeable to gases. In this case, the heat exchange element 2 becomes a sensible heat exchange element.

[0023] The exhaust fan 3 is a fan that takes in exhaust air flow 12 through the inside air port 4 and expels it from the exhaust port 5. The exhaust fan 3 has an exhaust fan and an exhaust motor (not shown). The exhaust fan is a centrifugal impeller such as a sirocco fan. The exhaust motor rotatably supports the exhaust fan. The exhaust motor is, for example, an alternating current motor (AC motor) or a direct current motor (DC motor). The exhaust fan 3 transports indoor air to the outdoors via the exhaust air duct 9 as exhaust air flow 12.

[0024] The intake blower 6 is a blower that takes in intake air flow 11 through the outside air inlet 7 and expels it from the intake air inlet 8. The intake blower has an intake fan and an intake motor (not shown). The intake fan is a centrifugal impeller such as an intake sirocco fan. The intake motor axially supports the intake fan so that it can rotate. The intake motor is, for example, an AC motor or a DC motor. The intake blower 6 transports outdoor air as intake air flow 11 through the intake air duct 10 to a specified indoor space.

[0025] Additionally, an exhaust air duct 9 connecting the inside air inlet 4 and the exhaust air duct 5, and an intake air duct 10 connecting the outside air inlet 7 and the intake air duct 8 are formed inside the heat exchanger-type ventilation device 1. An exhaust air flow 12 drawn in by the exhaust fan 3 passes through the heat exchange element 2 and the exhaust fan 3 in the exhaust air duct 9 and is discharged to the outdoors through the exhaust air duct 5. An intake air flow 11 drawn in by the intake fan 6 passes through the heat exchange element 2 and the intake fan 6 in the intake air duct 10 and is supplied to a predetermined indoor space through the intake air duct 8. In other words, the heat exchanger-type ventilation device 1 includes the intake air duct 10 for transporting air drawn in from the outdoors through the outside air inlet 7 to a predetermined indoor space through the intake air duct 8. The heat exchanger-type ventilation device 1 also includes the exhaust air duct 9 for transporting air drawn in from a predetermined indoor space through the inside air inlet 4 to the outdoors through the exhaust air duct 5.

[0026] When performing heat exchange ventilation, the heat exchange ventilation device 1 operates the exhaust fan 3 and the intake fan 6, and heat exchange occurs in the heat exchange element 2 between the exhaust airflow 12 flowing through the exhaust airflow 9 and the intake airflow 11 flowing through the intake airflow 10. As a result, when performing ventilation, the heat exchange ventilation device 1 transfers heat from the intake airflow 11 taken into a designated indoor space to the exhaust airflow 12 discharged outdoors, thereby suppressing the inflow of unnecessary heat. As a result, during the Japanese summer, when performing ventilation, the increase in indoor temperature due to air with a high outdoor temperature can be suppressed. Furthermore, during ventilation, the heat exchange ventilation device 1 transfers heat from the exhaust airflow 12 discharged outdoors to the intake airflow 11 taken into a designated indoor space, thereby suppressing the release of unnecessary heat and recovering heat indoors. As a result, during ventilation in the Japanese winter, when performing ventilation, the decrease in indoor temperature due to air with a low outdoor temperature can be suppressed.

[0027] For example, the intake fan 6 is provided downstream of the heat exchange element 2 in the intake airflow path 10. Specifically, the intake fan 6 is provided downstream of the heat exchange element 2 in the intake airflow path 10 and upstream of the intake port 8.

[0028] Furthermore, for example, the exhaust fan 3 is provided downstream of the heat exchange element 2 in the exhaust air duct 9. Specifically, the exhaust fan 3 is provided downstream of the heat exchange element 2 in the exhaust air duct 9 and upstream of the exhaust port 5.

[0029] The differential pressure detection unit 13 detects the pressure difference between the air pressure P1 in a predetermined indoor space and the outdoor air pressure P2, and supplies information on the detected pressure difference to the control device 14. The pressure difference is expressed as "pressure P1 - pressure P2".

[0030] 1, differential pressure detection unit 13 is disposed near exhaust port 5 and near inside air port 4, and detects a pressure difference by regarding the air pressure near exhaust port 5 as the outdoor air pressure and the air pressure near inside air port 4 as the air pressure in a predetermined space. The vicinity of exhaust port 5 specifically means downstream of exhaust fan 3 and upstream of exhaust port 5 in exhaust air duct 9. The vicinity of inside air port 4 specifically means downstream of inside air port 4 and upstream of heat exchange element 2 in exhaust air duct 9. Differential pressure detection unit 13 is, for example, a micro-differential pressure sensor.

[0031] Since the differential pressure detection unit 13 is located inside the housing of the heat exchanger-type ventilation device 1, the heat exchanger-type ventilation device 1 is easy to install and the installation work is also simple. The differential pressure detection unit 13 may be located in a predetermined space indoors and outdoors as long as it can detect the pressure difference, but in this case, information must be obtained from the differential pressure detection unit 13 located away from the housing of the heat exchanger-type ventilation device 1, which may make the installation work more complicated than the configuration in Figure 1.

[0032] The control device 14 is electrically connected to the exhaust fan 3, the intake fan 6, the differential pressure detection unit 13, and the operating device 16 so as to be able to communicate with each other, and controls the heat exchange type ventilation device 1.

[0033] The operation device 16 is, for example, a remote control. The operation device 16 has a user interface that can be operated by a user, and receives inputs such as the set air volume from the user. The operation device 16 transmits information such as the set air volume to the control device 14.

[0034] 2 is a schematic functional block diagram of the control device 14 and its peripheral configuration in FIG. 1. The control device 14 includes an acquisition unit 20, a determination unit 22, and a control unit 24. The configuration of the control device 14 can be realized in hardware terms using the CPU, memory, and other LSIs of any computer, and in software terms using programs loaded into memory, but the diagram depicts functional blocks realized by the cooperation of these. Therefore, it will be understood by those skilled in the art that these functional blocks can be realized in various forms using only hardware, only software, or a combination of both.

[0035] The acquisition unit 20 acquires information transmitted from the operation device 16 and supplies the acquired information to the determination unit 22 and the control unit 24 .

[0036] The control unit 24 controls the intake air blower 6 and the exhaust air blower 3. During normal ventilation operation, the control unit 24 performs ventilation air volume control, which controls the air volume of each of the intake air blower 6 and the exhaust air blower 3 to a set air volume supplied from the operation device 16. In controlling the ventilation air volume, the control unit 24 may set the set air volume using various known techniques. For example, the control unit 24 may automatically set the set air volume based on the temperature difference between the indoors and outdoors detected by a temperature sensor (not shown).

[0037] The control unit 24 periodically starts a judgment air volume control at a predetermined cycle to make the intake air volume by the intake fan 6 larger than the exhaust air volume by the exhaust fan 3, and performs the judgment air volume control for a predetermined time. Assume that a window is provided between a predetermined indoor space and the outdoors. If the window in the predetermined space is closed, the judgment air volume control causes the air pressure in the predetermined space to be higher than the air pressure outdoors, and the predetermined space becomes positive pressure. Since the predetermined space becomes positive pressure when the window is closed, it is possible to prevent outside air containing pollen, dust, etc. from directly flowing into the predetermined space through gaps in the building.

[0038] The predetermined period may be, for example, a period ranging from several minutes to several tens of minutes, or may be approximately 10 minutes. The predetermined time is shorter than the predetermined period. The predetermined time may be, for example, a period ranging from 10 seconds to several minutes, or may be approximately 30 seconds. The predetermined period and the predetermined time can each be appropriately determined through experiments or simulations.

[0039] The predetermined cycle and the predetermined time may be preset when the heat exchanger ventilation device 1 is shipped from the factory, or may be set by a user through input operations on the operation device 16. A setting unit (not shown) provided in the heat exchanger ventilation device 1 may receive settings for the predetermined cycle and the predetermined time from an installer when the heat exchanger ventilation device 1 is installed in a building, and may transmit the received information to the control device 14.

[0040] In the judgment air volume control, the control unit 24 preferably stops the exhaust fan 3. By stopping the exhaust fan 3, it is possible to create a positive pressure in the specified space in a shorter time when the window is closed. Furthermore, the differential pressure detection unit 13 can detect the pressure difference based on the air pressure near the exhaust port 5 and the air pressure near the inside air port 4 when there is no exhaust flow, so it can more accurately detect the pressure difference between the air pressure in the specified space and the outdoor air pressure without being affected by the exhaust flow.

[0041] The determination unit 22 periodically determines the open / closed state of a window in a predetermined space. Specifically, as a determination process for determining the open / closed state of a window, the determination unit 22 determines the open / closed state of the window based on the pressure difference detected by the differential pressure detection unit 13 after the control unit 24 performs the determination airflow control for a predetermined time. The determination unit 22 may execute the determination process when a predetermined time has elapsed since the control unit 24 started the determination airflow control.

[0042] In the determination process, if the pressure difference after the determination air volume control is performed for a predetermined time is equal to or less than a predetermined value, the determination unit 22 determines that the window is open. The predetermined value can be determined appropriately through experiments or simulations so that the open / closed state of the window can be appropriately determined. In this case, it is assumed that the air pressure in the predetermined space and the outdoor air pressure are equal when the window is open.

[0043] In the determination process, if the pressure difference after the determination air volume control has been performed for a predetermined time is greater than a predetermined value, the determination unit 22 determines that the window is closed. In this case, it is assumed that the predetermined space is under positive pressure due to the window being closed.

[0044] In this way, by determining the open / closed state of the window based on the pressure difference, it is possible to make the determination without installing an open / close sensor on the window, and therefore the heat exchange type ventilation device 1 is easy to install.

[0045] When the determination unit 22 determines that the window is closed, the control unit 24 restarts the ventilation air volume control. That is, the control unit 24 restarts the normal ventilation operation. As a result, when the window is closed, the heat exchange ventilation by the heat exchange type ventilator 1 can be performed.

[0046] When determination unit 22 determines that the window is open, control unit 24 reduces the airflow rate of at least one of air supply fan 6 and exhaust fan 3 compared to when the window is determined to be closed. Specifically, when determination unit 22 determines that the window is open, control unit 24 reduces the airflow rate of at least one of air supply fan 6 and exhaust fan 3 below the set airflow rate.

[0047] The control unit 24 may reduce the airflow rate of one of the air supply fan 6 and the exhaust fan 3 by stopping the other of the air supply fan 6 and the exhaust fan 3. When the control unit 24 reduces the airflow rate of one of the air supply fan 6 and the exhaust fan 3 below the set airflow rate, the control unit 24 controls the airflow rate of the other of the air supply fan 6 and the exhaust fan 3 to the set airflow rate.

[0048] This allows for less power consumption when the window is open than when it is closed. This reduces the amount of power consumption. Even if the airflow rate of at least one of the intake fan 6 and the exhaust fan 3 is reduced, natural ventilation can occur through the open window. This prevents a decrease in ventilation rate.

[0049] When the determination unit 22 determines that a window is open, the control unit 24 preferably stops both the intake fan 6 and the exhaust fan 3. This allows for a greater reduction in power consumption. Even if both the intake fan 6 and the exhaust fan 3 are stopped, natural ventilation can be achieved through the open window.

[0050] For example, in Japan, many homes have their windows open in the spring or autumn, or in the mornings and evenings of summer. In such situations, ventilation is possible through the windows, and the temperature difference between indoors and outdoors is relatively small. Therefore, it can be said that a comparative example in which normal ventilation operation using the heat exchanger-type ventilation device 1 is performed 24 hours a day wastes electricity. Furthermore, compared to a ventilation device without a heat exchanger element 2, the pressure loss of the heat exchanger-type ventilation device 1 is relatively large, so the power consumption of each of the intake air blower 6 and the exhaust air blower 3 is relatively large. Therefore, according to the embodiment, the power consumption is significantly reduced, and the electricity bill is also significantly reduced.

[0051] Even if it is determined that a window is open and, for example, the supply air blower 6 and the exhaust air blower 3 are stopped, the control unit 24 periodically starts the judgment air volume control at a predetermined cycle, and the judgment unit 22 executes the judgment process in accordance with the judgment air volume control, so that when the window is closed, normal ventilation operation is automatically resumed. Therefore, the user does not need to operate the heat exchange type ventilator 1, which is highly convenient.

[0052] Here, for example, the operation device 16 may receive an input of the size of a predetermined indoor space from a user. A setting unit (not shown) may receive a setting of the size of the predetermined space from a construction worker. The acquisition unit 20 may acquire information on the size of the predetermined space transmitted from the operation device 16 or the setting unit, and supply the acquired information to the control unit 24 and the determination unit 22.

[0053] In the first setting process, the control unit 24 and the determination unit 22 may set a longer predetermined time as the predetermined space becomes larger. When the window is closed and the airflow rate is constant, the larger the predetermined space becomes, the smaller the pressure difference that occurs over a certain time period becomes. Therefore, by lengthening the predetermined time period, the pressure difference can be increased, and erroneous determination of the open / closed state of the window can be suppressed.

[0054] As the second setting process, the control unit 24 may set a larger absolute value for the difference in air volume between the supply air volume and the exhaust air volume in the judgment air volume control, as the predetermined space becomes larger. When the window is closed, if the air volume is constant, the larger the predetermined space becomes, and therefore the pressure difference generated over a certain period of time becomes smaller. Therefore, by increasing the difference in air volume, the pressure difference can be increased, and erroneous determination of the open / closed state of the window can be suppressed.

[0055] As the third setting process, the determination unit 22 may set a smaller predetermined value as the predetermined space becomes larger. When the window is closed and the airflow rate is constant, the larger the predetermined space becomes, the smaller the pressure difference that occurs over a certain period of time becomes. Therefore, by setting a smaller predetermined value, the determination accuracy can be improved.

[0056] The operation device 16 may also receive an input of the level of airtightness performance of the predetermined space from a user. A setting unit (not shown) may receive a setting of the level of airtightness performance of the predetermined space from a construction worker. The acquisition unit 20 may acquire information on the level of airtightness performance of the predetermined space transmitted from the operation device 16 or the setting unit, and supply the acquired information to the determination unit 22.

[0057] As a fourth setting process, the determination unit 22 may set a smaller predetermined value as the airtightness of the predetermined space decreases. When the window is closed and the air volume is constant, the pressure difference generated in a certain time period decreases as the airtightness of the predetermined space decreases due to the number of gaps and the like. Therefore, by reducing the predetermined value, the determination accuracy can be improved.

[0058] At least two of the first to fourth setting processes may be executed.

[0059] Fig. 3 is a flowchart showing the processing of the heat exchange type ventilation device 1 of Fig. 1. The processing of Fig. 3 is started at predetermined intervals.

[0060] The control unit 24 starts the judgment air volume control (S10), and if a predetermined time has not elapsed since the start of the judgment air volume control (N in S12), the process returns to S12. If a predetermined time has elapsed since the start of the judgment air volume control (Y in S12), the judgment unit 22 acquires the pressure difference detected by the differential pressure detection unit 13 (S14), and determines whether or not the window is open based on the pressure difference (S16).

[0061] If the window is open (Y in S16), the control unit 24 controls the airflow rate of at least one of the air supply fan 6 and the exhaust fan 3 to be less than the set airflow rate (S18), and the process ends. If the window is not open (N in S16), the control unit 24 controls the airflow rate of each of the air supply fan 6 and the exhaust fan 3 to be the set airflow rate (S20), and the process ends.

[0062] In the above explanation, an example has been described in which the open / closed state of a window is determined by controlling the predetermined space to have a positive pressure when the window is closed, but as will be explained below, the open / closed state of a window may also be determined by controlling the predetermined space to have a negative pressure when the window is closed. The following explanation will focus on the differences from the case in which the predetermined space is controlled to have a positive pressure.

[0063] The differential pressure detection unit 13 detects the pressure difference between the outdoor air pressure P2 and the air pressure P1 in the predetermined space, and supplies information on the detected pressure difference to the control device 14. The pressure difference is expressed as "pressure P2 - pressure P1".

[0064] Unlike the example shown in Fig. 1, differential pressure detection unit 13 is disposed near outside air outlet 7 and near air intake port 8, and detects the pressure difference by regarding the air pressure near outside air outlet 7 as the outdoor air pressure and the air pressure near air intake port 8 as the air pressure in a predetermined space. The vicinity of outside air outlet 7 specifically means downstream of outside air outlet 7 in intake air duct 10 and upstream of heat exchange element 2. The vicinity of air intake port 8 specifically means downstream of intake air blower 6 in intake air duct 10 and upstream of air intake port 8.

[0065] The control unit 24 periodically starts, at a predetermined cycle, a judgment air volume control for making the exhaust air volume by the exhaust fan 3 larger than the intake air volume by the intake fan 6, and performs the judgment air volume control for a predetermined time. By the judgment air volume control, if the window in the predetermined space is closed, the air pressure in the predetermined space becomes lower than the air pressure outside, and the predetermined space becomes negative pressure.

[0066] In the judgment air volume control, the control unit 24 preferably stops the intake air blower 6. By stopping the intake air blower 6, it is possible to create a negative pressure in the specified space in a shorter time when the window is closed. Furthermore, the differential pressure detection unit 13 can detect the pressure difference based on the air pressure near the outside air inlet 7 and the air pressure near the intake air inlet 8 when there is no intake air flow, so it can more accurately detect the pressure difference between the outdoor air pressure and the air pressure in the specified space without being affected by the intake air flow.

[0067] In the determination process, if the pressure difference after the determination air volume control is performed for a predetermined time is equal to or less than a predetermined value, the determination unit 22 determines that the window is open. The predetermined value can be determined appropriately through experiments or simulations so that the open / closed state of the window can be appropriately determined. In this case, it is assumed that the air pressure in the predetermined space and the outdoor air pressure are equal when the window is open.

[0068] In the determination process, if the pressure difference after the determination air volume control has been performed for a predetermined time is greater than a predetermined value, the determination unit 22 determines that the window is closed. In this case, it is assumed that the predetermined space is under negative pressure due to the window being closed.

[0069] The control by the control unit 24 in accordance with the determination result of the determination unit 22 is the same as the control described above. Also, at least one of the first to fourth setting processes may be executed.

[0070] In this way, the aforementioned effect of reducing power consumption can also be achieved by determining whether the window is open or closed by controlling the predetermined space to have a negative pressure when the window is closed.

[0071] In addition, from the viewpoint of preventing outside air containing pollen, dust, etc. from directly flowing into the specified space through gaps in the building, it is preferable to control the specified space so that it becomes positive pressure when the window is closed.

[0072] The present disclosure has been described above based on the embodiments. These embodiments are merely examples, and it will be understood by those skilled in the art that various modifications are possible in the combination of each component or each treatment process, and that such modifications are also within the scope of the present disclosure.

[0073] (First Modification) For example, in a configuration in which control is performed so that a predetermined space has a positive pressure when a window is closed, differential pressure detection unit 13 may detect a pressure difference by regarding the air pressure near outside air outlet 7 as the outdoor air pressure and the air pressure near inside air outlet 4 as the air pressure in the predetermined space. Differential pressure detection unit 13 may detect a pressure difference by regarding the air pressure near outside air outlet 7 as the outdoor air pressure and the air pressure near air intake port 8 as the air pressure in the predetermined space. Differential pressure detection unit 13 may detect a pressure difference by regarding the air pressure near exhaust port 5 as the outdoor air pressure and the air pressure near air intake port 8 as the air pressure in the predetermined space.

[0074] Furthermore, in a configuration in which control is performed so that a predetermined space is under negative pressure when a window is closed, the differential pressure detection unit 13 may detect a pressure difference by taking the air pressure near the outside air outlet 7 as the outdoor air pressure and the air pressure near the inside air outlet 4 as the air pressure in the predetermined space. The differential pressure detection unit 13 may detect a pressure difference by taking the air pressure near the exhaust outlet 5 as the outdoor air pressure and the air pressure near the inside air outlet 4 as the air pressure in the predetermined space. The differential pressure detection unit 13 may detect a pressure difference by taking the air pressure near the exhaust outlet 5 as the outdoor air pressure and the air pressure near the intake air outlet 8 as the air pressure in the predetermined space. This modification can improve the flexibility of the configuration of the heat exchange type ventilation device 1.

[0075] (Second Modification) The determination unit 22 may periodically determine the open / closed state of the window based on the detection result of an open / close sensor provided on the window. The open / close sensor detects whether the window is open or closed using known technology. In this case, the differential pressure detection unit 13 may not be provided. The control unit 24 may not need to perform the determination air volume control. This modification improves the flexibility of the configuration of the heat exchange type ventilation device 1. It also simplifies the control.

[0076] (Third Modification) The heat exchange element 2 does not have to be provided. In this case, the ventilation device performs ventilation without heat exchange. In this modification, the intake air duct 10 also transports air drawn in from outdoors through the outside air port 7 to a specified space indoors through the intake air port 8. The exhaust air duct 9 transports air drawn in from a specified space indoors through the inside air port 4 to the outdoors through the exhaust air port 5. In this modification, the amount of power consumption can be reduced in a ventilation device that performs ventilation without heat exchange.

[0077] At least two of the first to third modifications may be combined.

[0078] One aspect of the present disclosure is as follows.

[0079] [Item 1] an air intake duct for transporting air drawn in from outdoors through the outdoor air intake port to a predetermined space indoors through the indoor air intake port; an intake air blower that transports the outdoor air as an intake air flow through the intake air duct to the predetermined space; an exhaust air duct for transporting air drawn in from the predetermined space through an indoor exhaust port to the outdoors through an outdoor exhaust port; an exhaust fan that transports the air in the predetermined space to the outdoors as an exhaust flow through the exhaust air duct; a determination unit that determines whether a window in the predetermined space is open or closed; a control unit that controls the intake air blower and the exhaust air blower, The control unit When the determination unit determines that the window is open, the ventilation device reduces the airflow rate of at least one of the intake air blower and the exhaust air blower compared to when the window is determined to be closed.

[0080] [Item 2] a differential pressure detection unit that detects the pressure difference between the air pressure in the predetermined space and the outdoor air pressure, The determination unit performs the determination process of determining the open / closed state of the window by: Item 1. The ventilation device according to item 1, wherein the control unit performs a judgment air volume control for a predetermined period of time to make the supply air volume by the supply air blower larger than the exhaust air volume by the exhaust air blower, and then determines the open / closed state of the window based on the pressure difference detected by the differential pressure detection unit.

[0081] [Item 3] The determination unit 3. The ventilation device according to item 2, wherein in the determination process, if the pressure difference after the determination air volume control has been performed for the predetermined time is equal to or less than a predetermined value, it is determined that the window is open.

[0082] [Item 4] The differential pressure detection unit The pressure of the air near the outdoor exhaust port is defined as the outdoor air pressure, The pressure difference is detected by taking the pressure of the air in the vicinity of the indoor exhaust port as the pressure of the air in the predetermined space, and The control unit 4. The ventilation device according to item 2 or 3, wherein the exhaust fan is stopped in the judgment air volume control.

[0083] [Item 5] a differential pressure detection unit that detects a pressure difference between the outdoor air pressure and the air pressure in the predetermined space, The determination unit performs the determination process of determining the open / closed state of the window by: Item 1. The ventilation device according to item 1, wherein the control unit performs a judgment air volume control for a predetermined time to make the exhaust air volume by the exhaust fan greater than the intake air volume by the intake fan, and then determines the open / closed state of the window based on the pressure difference detected by the differential pressure detection unit.

[0084] [Item 6] The determination unit 6. The ventilation device according to item 5, wherein in the determination process, if the pressure difference after the determination air volume control has been performed for the predetermined time is equal to or less than a predetermined value, it is determined that the window is open.

[0085] [Item 7] The differential pressure detection unit The pressure of the air near the outdoor air supply port is defined as the outdoor air pressure, The pressure difference is detected by taking the pressure of the air in the vicinity of the indoor air supply port as the pressure of the air in the predetermined space, and The control unit 7. The ventilation device according to item 5 or 6, wherein the supply air blower is stopped in the judgment air volume control.

[0086] [Item 8] 8. The ventilation device according to any one of items 2 to 7, wherein the larger the predetermined space, the longer the predetermined time is set.

[0087] [Item 9] 9. The ventilation device according to any one of items 2 to 8, wherein the absolute value of the air volume difference between the supply air volume and the exhaust air volume in the judgment air volume control is set to be larger as the predetermined space is larger.

[0088] [Item 10] 7. The ventilation device according to item 3 or 6, wherein the larger the predetermined space, the smaller the predetermined value is set.

[0089] [Item 11] 7. The ventilation device according to item 3 or 6, wherein the lower the airtightness of the predetermined space, the smaller the predetermined value is set.

[0090] [Item 12] The differential pressure detection unit the pressure of the air in the vicinity of the outdoor-side exhaust port or the outdoor-side air intake port is defined as the outdoor air pressure; 7. The ventilation device according to any one of items 2, 3, 5, and 6, wherein the pressure difference is detected by taking the air pressure near the indoor exhaust port or the air pressure near the indoor air intake port as the air pressure in the specified space.

[0091] [Item 13] 13. The ventilation device according to any one of items 1 to 12, comprising a heat exchange element for exchanging heat between the intake air flow and the exhaust air flow. [Industrial Applicability]

[0092] The ventilation device of the present disclosure is useful as a device for performing ventilation in a building. [Explanation of symbols]

[0093] 1...heat exchange type ventilation device, 2...heat exchange element, 3...exhaust fan, 4...inner air vent, 5...exhaust outlet, 6...intake fan, 7...outside air vent, 8...intake air vent, 9...exhaust air duct, 10...intake air duct, 11...intake air flow, 12...exhaust flow, 13...differential pressure detection unit, 14...control device, 16...operation device, 20...acquisition unit, 22...determination unit, 24...control unit

Claims

1. an air intake duct for transporting air drawn in from outdoors through the outdoor air intake port to a predetermined space indoors through the indoor air intake port; an intake air blower that transports the outdoor air as an intake air flow through the intake air duct to the predetermined space; an exhaust air duct for transporting air drawn in from the predetermined space through an indoor exhaust port to the outdoors through an outdoor exhaust port; an exhaust fan that transports the air in the predetermined space to the outdoors as an exhaust flow through the exhaust air duct; a determination unit that determines whether a window in the predetermined space is open or closed; a control unit that controls the intake air blower and the exhaust air blower, The control unit When the determination unit determines that the window is open, the ventilation device reduces the airflow rate of at least one of the intake air blower and the exhaust air blower compared to when the window is determined to be closed.

2. a differential pressure detection unit that detects the pressure difference between the air pressure in the predetermined space and the outdoor air pressure, The determination unit performs the determination process of determining the open / closed state of the window by:

2. The ventilation device according to claim 1, wherein the control unit performs a judgment air volume control for a predetermined period of time to make the supply air volume by the supply air blower greater than the exhaust air volume by the exhaust air blower, and then determines the open / closed state of the window based on the pressure difference detected by the differential pressure detection unit.

3. The determination unit The ventilation device according to claim 2 , wherein in the determination process, if the pressure difference after the determination air volume control has been performed for the predetermined time is equal to or less than a predetermined value, it is determined that the window is open.

4. The differential pressure detection unit The pressure of the air near the outdoor exhaust port is defined as the outdoor air pressure, The pressure difference is detected by taking the pressure of the air in the vicinity of the indoor exhaust port as the pressure of the air in the predetermined space, and The control unit The ventilation device according to claim 2 , wherein the exhaust fan is stopped in the air volume determination control.

5. a differential pressure detection unit that detects a pressure difference between the outdoor air pressure and the air pressure in the predetermined space, The determination unit performs the determination process of determining the open / closed state of the window by:

2. The ventilation device according to claim 1, wherein the control unit performs a judgment air volume control for a predetermined period of time to make the exhaust air volume by the exhaust fan greater than the intake air volume by the intake fan, and then determines whether the window is open or closed based on the pressure difference detected by the differential pressure detection unit.

6. The determination unit The ventilation device according to claim 5 , wherein, in the determination process, if the pressure difference after the determination air volume control has been performed for the predetermined time is equal to or less than a predetermined value, it is determined that the window is open.

7. The differential pressure detection unit The pressure of the air near the outdoor air supply port is defined as the outdoor air pressure, The pressure difference is detected by taking the pressure of the air in the vicinity of the indoor air supply port as the pressure of the air in the predetermined space, and The control unit The ventilation device according to claim 5 , wherein the air supply blower is stopped in the determination air volume control.

8. The ventilation device according to any one of claims 2 to 7, wherein the larger the predetermined space, the longer the predetermined time is set.

9. The ventilation device according to any one of claims 2 to 7, wherein the absolute value of the difference in air volume between the supply air volume and the exhaust air volume in the air volume determination control is set to be larger as the predetermined space is larger.

10. The ventilation device according to claim 3 or 6, wherein the larger the predetermined space, the smaller the predetermined value is set.

11. The ventilation device according to claim 3 or 6, wherein the predetermined value is set to be smaller as the airtightness of the predetermined space becomes lower.

12. The differential pressure detection unit the pressure of the air in the vicinity of the outdoor-side exhaust port or the outdoor-side air intake port is defined as the outdoor air pressure; 7. The ventilation system according to claim 2, wherein the pressure difference is detected by taking the pressure of air in the vicinity of the indoor exhaust port or the indoor air intake port as the pressure of air in the predetermined space.

13. The ventilation device according to any one of claims 1 to 7, further comprising a heat exchange element for exchanging heat between the intake air flow and the exhaust air flow.

Images