JP2024106571A - Ventilation system - Google Patents

Abstract

A technique is provided that can reduce the frequency of replacing filters in a ventilation system.
[Solution] In a ventilation device (10), an exhaust air duct (22) communicates between an indoor air inlet (14) and an exhaust port (16). An intake air duct (24) communicates between an outside air inlet (18) and an intake port (20). A first filter (38) is disposed in the intake air duct (24). A first bypass air duct (28) is capable of directing air passing through the exhaust air duct (22) to a position in the intake air duct (24) between the first filter (38) and the intake port (20). A first air duct switching unit (44) is capable of switching between a first state in which the first bypass air duct (28) is closed and a second state in which the first bypass air duct (28) is opened and the air that has passed through the first bypass air duct (28) from the exhaust air duct (22) flows back into the intake air duct (24) from the first filter (38) to the outside air inlet (18).
[Selected Figure] Figure 1

Description

This disclosure relates to a ventilation device.

One method of mechanically ventilating the indoor air of a building is type 1 ventilation. This is done by using two ventilation devices, and the supply airflow that flows from the outside into the room and the exhaust airflow that flows from the room to the outside are each driven by mechanical ventilation. One type of ventilation device that achieves type 1 ventilation is the heat exchange unit. This is a ventilation device that prevents the heat energy added to the indoor air by the air conditioner from being wasted by the exhaust airflow ventilation device in environments with large temperature and humidity differences between the inside and outside of the room, such as summer and winter. The heat exchange unit is equipped with two fans that drive the supply airflow and the exhaust airflow, as well as a heat exchange element that exchanges heat between the supply airflow and the exhaust airflow. Heat exchange units are known to be effective in reducing energy loss throughout the building by operating them constantly, and are widely used.

On the other hand, in a heat exchange ventilation unit, there is a possibility that airborne particles such as insects and dust may enter the room if they get mixed in with the intake air flow. Therefore, a structure is known in which a filter is installed upstream of the heat exchange element from the intake air flow in a heat exchange unit to prevent airborne particles from getting mixed in with the intake air flow. For example, Patent Document 1 discloses a heat exchange ventilation device equipped with a filter that collects dust contained in the intake air flow.

JP 2015-121356 A

When airborne particles adhere to the ventilation system filter and cause it to become clogged, the airflow decreases, so the filter must be replaced periodically. However, when replacing the filter, workers may touch a dirty filter, and airborne particles may fall off the filter and enter the room. For this reason, it is desirable to replace the filter as infrequently as possible.

This disclosure has been made to solve the above problems, and aims to provide a technology that can reduce the frequency of replacing ventilation system filters.

In order to solve the above problems, a ventilation device according to one aspect of the present disclosure includes an exhaust air duct that connects an indoor air inlet and an exhaust air duct, an air supply air duct that connects an outdoor air inlet and an air supply air duct, a first filter disposed in the air supply air duct, a first bypass air duct that can direct air passing through the exhaust air duct to a position in the air supply air duct between the first filter and the air supply air duct, and a first air duct switching unit that can switch between a first state in which the first bypass air duct is closed and a second state in which the first bypass air duct is opened and air that has passed through the first bypass air duct from the exhaust air duct is caused to flow back into the air supply air duct from the first filter to the outdoor air inlet.

In addition, any combination of the above components, and conversions of the expressions of this disclosure between methods, devices, systems, etc., are also valid aspects of this disclosure.

This disclosure provides technology that can reduce the frequency of replacing ventilation system filters.

1 is a plan view illustrating a schematic configuration of a ventilation device according to a first embodiment. FIG. 2 is a plan view showing an operating state of the ventilation device of FIG. 1 during normal ventilation operation. FIG. 2 is a plan view showing an operating state of the ventilation device of FIG. 1 during a first discharge operation. FIG. 2 is a plan view showing an operating state of the ventilation device of FIG. 1 during a second exhaust operation. FIG. 11 is a plan view illustrating a schematic configuration of a ventilation device according to a second embodiment.

Below, the embodiments for carrying out the present disclosure will be described with reference to the attached drawings. In the embodiments and modified examples, the same or equivalent components and members are given the same reference numerals, and duplicated descriptions will be omitted as appropriate. Furthermore, the dimensions of the members in each drawing are shown enlarged or reduced as appropriate to facilitate understanding. Furthermore, some of the members that are not important for explaining the embodiments will be omitted in each drawing.

(First embodiment)
1 is a plan view showing a schematic configuration of a ventilation device 10 according to a first embodiment. The ventilation device 10 can be installed in the ceiling, in a side wall, or under a floor of a building, and ventilates an indoor space. The ventilation device 10 is a heat exchange device that ventilates while exchanging heat between air exhausted from indoors to outdoors and air supplied from outdoors to indoors.

The ventilation device 10 draws in air from rooms inside the building through an indoor intake duct (not shown) and exhausts it to the outside of the building through an exhaust duct (not shown). The ventilation device 10 also draws in air from outside the building through an outside air intake duct (not shown) and supplies the air to rooms inside the building through an air supply duct (not shown).

The ventilation device 10 can perform heat exchange ventilation operation, normal ventilation operation, first exhaust operation, and second exhaust operation. The heat exchange ventilation operation is a first type of ventilation operation that involves heat exchange, and is assumed to be performed, for example, during periods when the indoor temperature and the outdoor temperature are relatively far apart. Figure 1 also shows the operating state of the ventilation device 10 during heat exchange ventilation operation.

Normal ventilation operation is a type 1 ventilation operation that does not involve heat exchange, and is expected to be performed, for example, when the indoor temperature and outdoor temperature are relatively close. Hereinafter, heat exchange operation and normal ventilation operation will be collectively referred to as "ventilation operation" as appropriate.

The first and second exhaust operations are for discharging airborne particles adhering to the filter inside the ventilation device 10 to the outdoors. Details of each operation will be described later.

As shown in FIG. 1, the ventilation device 10 includes a main body case 12, an indoor air inlet 14, an exhaust port 16, an outdoor air inlet 18, an air supply port 20, an exhaust air duct 22, an air supply air duct 24, a partition wall 26, a first bypass air duct 28, a second bypass air duct 30, a heat exchanger 32, an exhaust fan 34, an air supply fan 36, a first filter 38, a second filter 40, a partition wall 42, a first air duct switching unit 44, a second air duct switching unit 46, and a control device 48.

The main body case 12 has a generally rectangular box-like outer shape in plan view. An exhaust port 16 and an outside air intake port 18 are provided side by side on one side of the main body case 12. An indoor intake port 14 and an air supply port 20 are provided side by side on the other side opposite the one side of the main body case 12.

The indoor air inlet 14 takes in indoor air (RA) as the first exhaust air flow A2a into the ventilation device 10. The exhaust air outlet 16 discharges the first exhaust air flow A2a from the ventilation device 10 to the outdoors as exhaust air (EA). The outdoor air inlet 18 takes in outdoor air (OA) into the ventilation device 10 as the supply air flow A1. The supply air outlet 20 discharges the supply air flow A1 from the ventilation device 10 to the outdoors as supply air (SA).

The exhaust air duct 22 is provided in the main body case 12 and connects the indoor air inlet 14 and the exhaust air duct 16. The supply air duct 24 is provided in the main body case 12 and connects the outdoor air inlet 18 and the supply air duct 20. In FIG. 1, the supply air flow A1 is shown generally by a thick dashed line, and the first exhaust air flow A2a is shown generally by a thick solid line. The flow directions of the supply air flow A1 and the first exhaust air flow A2a are indicated by arrows.

The heat exchange unit 32 is provided in the main body case 12, includes a heat exchange element, and exchanges heat between the air passing through the exhaust air duct 22 and the air passing through the supply air duct 24. The heat exchange unit 32 includes a portion of each of the supply air duct 24 and the exhaust air duct 22 inside. The supply air duct 24 and the exhaust air duct 22 in the heat exchange unit 32 are independent air ducts. Heat exchange between the air of the supply air flow A1 and the air of the first exhaust air flow A2a improves heating efficiency in winter and cooling efficiency in summer. The heat exchange unit 32 may further exchange humidity between the air of the supply air flow A1 and the air of the first exhaust air flow A2a.

The partition wall 26 separates the exhaust air passage 22 and the supply air passage 24 between one side of the main body case 12 and the heat exchange section 32, and between the other side of the main body case 12 and the heat exchange section 32.

The exhaust fan 34 is disposed between the heat exchange section 32 and the exhaust port 16 in the exhaust air duct 22, and directs air from the indoor intake port 14 to the exhaust port 16.

The supply air fan 36 is disposed between the heat exchange section 32 and the supply air port 20 in the supply air duct 24, and directs air from the outside air intake 18 to the supply air port 20.

As an example, the exhaust fan 34 and the supply fan 36 are each a centrifugal fan, and include a fan and a motor that drives the fan to rotate.

The exhaust air duct 22 has a normal ventilation air duct 22a that connects from the indoor air inlet 14 to the exhaust fan 34 without passing through the heat exchange unit 32, and a heat exchange air duct 22b that connects from the indoor air inlet 14 to the exhaust fan 34 through the heat exchange unit 32. The normal ventilation air duct 22a is, for example, an air duct that passes behind the heat exchange unit 32.

The partition wall 42 separates the normal ventilation air duct 22a and the heat exchange air duct 22b between the fourth damper 50d (described later) and the heat exchange section 32.

The first bypass air passage 28 penetrates the partition wall 26 on the exhaust port 16 side. The first bypass air passage 28 allows air passing through the exhaust air passage 22 between the exhaust fan 34 and the exhaust port 16 to flow to a position between the first filter 38 and the intake port 20 in the intake air passage 24, specifically, to a position between the first filter 38 and the heat exchanger 32.

The second bypass air duct 30 penetrates the partition wall 26 on the intake port 20 side. The second bypass air duct 30 can direct air from a position between the intake fan 36 and the intake port 20 in the intake air duct 24 to a position between the second filter 40 and the heat exchange unit 32 in the heat exchange air duct 22b.

The first filter 38 is an air filter that is disposed in the air supply duct 24 between the outside air intake 18 and the first bypass duct 28, and removes airborne particles such as insects and dust from the air that flows in through the outside air intake duct 18, and outputs purified air.

The second filter 40 is an air filter that is disposed between the second bypass air duct 30 and the fourth damper 50d in the heat exchange air duct 22b, and removes airborne particles such as dust from the air that flows in from the indoor air inlet 14, and outputs purified air. The second filter 40 is provided to prevent airborne particles from entering the heat exchange section 32. The first filter 38 and the second filter 40 may be HEPA (High Efficiency Particulate Air) filters, etc.

The first air passage switching unit 44 can be switched between a first state (see Figures 1, 2, and 4) in which the first bypass air passage 28 is closed, and a second state (see Figure 3) in which the first bypass air passage 28 is opened and air supplied from the exhaust air passage 22 and passed through the first bypass air passage 28 is caused to flow back into the supply air passage 24 from the first filter 38 to the outside air intake 18.

The first air passage switching unit 44 has a first damper 50a and a second damper 50b. The first damper 50a is disposed on the exhaust air passage 22 side of the first bypass air passage 28, and closes the first bypass air passage 28 in the first state (see Figures 1, 2, and 4), and closes the exhaust air passage 22 between the first bypass air passage 28 and the exhaust port 16 in the second state (see Figure 3).

The second damper 50b is disposed on the supply air passage 24 side of the first bypass air passage 28, closes the first bypass air passage 28 in the first state (see Figures 1, 2, and 4), and closes the supply air passage 24 between the first bypass air passage 28 and the heat exchange section 32 in the second state (see Figure 3).

The second air passage switching unit 46 can be switched between a first state (see FIG. 1) in which air drawn in from the indoor air inlet 14 is passed through the heat exchange air passage 22b, a second state (see FIGS. 2 and 3) in which air drawn in from the indoor air inlet 14 is passed through the normal ventilation air passage 22a, and a third state (see FIG. 4). The second air passage switching unit 46 closes the second bypass air passage 30 in the first and second states.

The third state is a state in which the second bypass air duct 30 is opened and the indoor air inlet 14 is closed, the air supplied from the supply air duct 24 and passing through the second bypass air duct 30 is caused to flow back into the heat exchange air duct 22b from the second filter 40 to just before the indoor air inlet 14, and the backflowing air is exhausted from the exhaust port 16 through the normal ventilation air duct 22a.

The second air passage switching unit 46 has a third damper 50c and a fourth damper 50d. The third damper 50c is disposed on the supply air passage 24 side of the second bypass air passage 30, and closes the second bypass air passage 30 in the first and second states (see Figures 1 to 3), and closes the supply air passage 24 between the second bypass air passage 30 and the air supply port 20 in the third state (see Figure 4).

The fourth damper 50d is disposed between the partition wall 42 of the exhaust air duct 22 and the indoor air inlet 14, and in the first state, closes the normal ventilation air duct 22a on the indoor air inlet 14 side and connects the heat exchange air duct 22b to the indoor air inlet 14 (see FIG. 1). In the second state, the fourth damper 50d closes the heat exchange air duct 22b on the indoor air inlet 14 side and connects the normal ventilation air duct 22a to the indoor air inlet 14 (see FIGS. 2 and 3). In the third state, the fourth damper 50d closes the indoor air inlet 14 and connects the heat exchange air duct 22b to the normal ventilation air duct 22a between the fourth damper 50d and the end of the partition wall 42 (see FIG. 4).

The first damper 50a, the second damper 50b, the third damper 50c, and the fourth damper 50d are partition plates for opening and closing the air passage, and are driven by an actuator (not shown) in response to the control of the control device 48.

The control device 48 has an integrating unit 60 and a control unit 62. In terms of hardware, the configuration of the control device 48 can be realized by the CPU, memory, and other LSIs of any computer, and in terms of software, by programs loaded into memory, but here we depict 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 ways by hardware alone, software alone, or a combination of both.

The control unit 62 controls the operation of the ventilation device 10 to one of heat exchange operation, normal ventilation operation, first exhaust operation, and second exhaust operation. The control unit 62 controls the first air path switching unit 44, the second air path switching unit 46, the exhaust fan 34, and the supply air fan 36 depending on the type of operation.

The control device 48 receives operation input from a user, for example, via a reception unit (not shown). The control unit 62 switches the operation of the ventilation device 10 between heat exchange ventilation operation and normal ventilation operation in response to the received operation input. Known technology can be used to switch between heat exchange ventilation operation and normal ventilation operation, and switching may be performed automatically in response to the detected air temperature, etc.

During heat exchange ventilation operation, the control unit 62 controls the first air passage switching unit 44 to the first state, controls the second air passage switching unit 46 to the first state, and controls the air volume of each of the exhaust fan 34 and the supply air fan 36 in response to, for example, a user's operational input.

The accumulating unit 60 includes a timer and accumulates the operating time of ventilation operations, including heat exchange ventilation operation and normal ventilation operation. The accumulated operating time is the sum of the accumulated operating time of heat exchange ventilation operation and the accumulated operating time of normal ventilation operation.

The heat exchange ventilation operation will be explained in more detail. During the heat exchange ventilation operation, as shown in FIG. 1, the first bypass air duct 28 is closed by the first damper 50a and the second damper 50b, and the second bypass air duct 30 is closed by the third damper 50c. The normal ventilation air duct 22a is closed by the fourth damper 50d, and the heat exchange ventilation air duct 22b is connected to the indoor air inlet 14.

As a result, during heat exchange operation, the exhaust air duct 22 and the supply air duct 24 are independent, and the first exhaust air flow A2a passes through the exhaust air duct 22 including the heat exchange air duct 22b, and the supply air flow A1 passes through the supply air duct 24. The first exhaust air flow A2a and the supply air flow A1 each pass through the heat exchange section 32, so that heat exchange occurs between them as described above.

Continuing the heat exchange operation may cause airborne particles 90 to accumulate on the outside air intake 18 side of the first filter 38. Because outdoor air flows into the outside air intake 18, the airborne particles 90 may include small insects. Airborne particles 92 may also accumulate on the indoor air intake 14 side of the second filter 40. The airborne particles 92 may mainly include dust. In general, the amount of airborne particles 90 adhering to the first filter 38 tends to be greater than the amount of airborne particles 92 adhering to the second filter 40.

Next, the normal ventilation operation will be described in more detail.
Fig. 2 is a plan view showing an operating state during normal ventilation operation of the ventilation device 10 in Fig. 1. During normal ventilation operation, the control unit 62 controls the first air-passage switching unit 44 to a first state, controls the second air-passage switching unit 46 to a second state, and controls the air volumes of the exhaust fan 34 and the supply air fan 36 in response to, for example, a user's operational input.

As shown in FIG. 2, the first bypass air passage 28 is closed by the first damper 50a and the second damper 50b, and the second bypass air passage 30 is closed by the third damper 50c. The heat exchange air passage 22b is closed by the fourth damper 50d, and the normal ventilation air passage 22a is connected to the indoor air inlet 14.

As a result, during normal ventilation operation, the exhaust air duct 22 and the supply air duct 24 are independent, and the second exhaust flow A2b passes through the exhaust air duct 22, which includes the normal ventilation air duct 22a, and the supply air flow A1 passes through the supply air duct 24. Since the second exhaust flow A2b does not pass through the heat exchange section 32, no heat exchange occurs between the second exhaust flow A2b and the supply air flow A1. Even if normal ventilation operation is continued, airborne particles 90 accumulate on the outside air intake port 18 side of the first filter 38.

When the operation time accumulated by the accumulating unit 60 exceeds a predetermined time, the control unit 62 temporarily suspends the heat exchange ventilation operation or normal ventilation operation being performed, and performs the first exhaust operation and the second exhaust operation in turn for a predetermined exhaust time each. The predetermined time can be appropriately determined by experiment or simulation, and may be, for example, a time ranging from several days to one week. The predetermined time may be set by the user according to the surrounding environment of the building in which the ventilation device 10 is used. For example, in a situation where there are many small insects outdoors and the first filter 38 is likely to become clogged in a short time, the predetermined time may be set to be shorter than one week. The predetermined exhaust time can be appropriately determined by experiment or simulation, and may be, for example, a few minutes.

The order of the first discharge operation and the second discharge operation is arbitrary. Below, an example in which the first discharge operation is performed first is described.

Figure 3 is a plan view showing the operating state of the ventilation device 10 in Figure 1 during the first exhaust operation. The first exhaust operation is an operation for exhausting the airborne particles 90 adhering to the first filter 38 from the outside air intake 18 to the outdoors by causing the third exhaust flow A2c to flow back through the first filter 38 and the outside air intake 18.

During the first exhaust operation, the control unit 62 controls the first air passage switching unit 44 to the second state, controls the second air passage switching unit 46 to the second state, controls the air volume of the exhaust fan 34 to the maximum settable air volume, and stops the supply air fan 36.

As shown in FIG. 3, the first damper 50a closes the exhaust air passage 22 between the first bypass air passage 28 and the exhaust port 16, and the second damper 50b closes the supply air passage 24 between the first bypass air passage 28 and the heat exchanger 32. As a result, the first bypass air passage 28 is opened. The exhaust air passage 22 communicates with the supply air passage 24 between the second damper 50b and the outside air intake port 18 and with the outside air intake port 18 via the first bypass air passage 28. The third damper 50c and the fourth damper 50d are in the same positions as during normal ventilation operation.

As a result, during the first exhaust operation, the exhaust fan 34 blows air, causing the third exhaust flow A2c to pass through the indoor air inlet 14, the exhaust air duct 22 including the normal ventilation air duct 22a, the first bypass air duct 28, and the supply air duct 24 between the second damper 50b and the outdoor air inlet 18, and exit to the outdoors through the outdoor air inlet 18.

In other words, the third exhaust flow A2c that has passed through the first bypass air passage 28 flows back into the supply air passage 24 between the second damper 50b and the outside air intake 18. The backflowing third exhaust flow A2c allows the airborne particles 90 on the outside air intake 18 side of the first filter 38 in the supply air passage 24 between the second damper 50b and the outside air intake 18 to be discharged to the outdoors through the outside air intake 18.

The air volume of the exhaust fan 34 is the maximum air volume that can be set, so that the airborne particles 90 in the first filter 38 can be easily discharged to the outdoors. In addition, the third exhaust flow A2c passes through the normal ventilation duct 22a, and the first bypass duct 28 directs the air passing through the exhaust duct 22 to a position between the first filter 38 and the heat exchanger 32 in the intake duct 24, so that the third exhaust flow A2c does not pass through the heat exchanger 32. This suppresses pressure loss in the third exhaust flow A2c, and allows a larger air volume to be sent to the first filter 38 compared to when the third exhaust flow A2c passes through the heat exchanger 32, making it easier to discharge the airborne particles 90.

As a result, the amount of airborne particles 90 adhering to the first filter 38 can be reduced or substantially eliminated, and the frequency with which the first filter 38 needs to be replaced can be reduced. In addition, when replacing the first filter 38, since there is less airborne particles 90 adhering to the first filter 38, the airborne particles 90 are less likely to fall into the room.

Figure 4 is a plan view showing the operating state of the ventilation device 10 in Figure 1 during the second exhaust operation. The second exhaust operation is an operation for exhausting the airborne particles 92 adhering to the second filter 40 to the outdoors through the exhaust port 16 by causing the air flowing through the supply air duct 24 to flow back through the second filter 40 and into the normal ventilation air duct 22a.

During the second exhaust operation, the control unit 62 controls the first air passage switching unit 44 to the first state, controls the second air passage switching unit 46 to the third state, and controls the airflow of each of the exhaust fan 34 and the supply air fan 36 to the maximum airflow that can be set.

As shown in FIG. 4, the first damper 50a and the second damper 50b are in the same position as during heat exchange ventilation operation and normal ventilation operation. The third damper 50c closes the supply air duct 24 between the second bypass air duct 30 and the supply air port 20, and as a result, the second bypass air duct 30 is opened. The fourth damper 50d closes the indoor intake port 14, and the heat exchange air duct 22b communicates with the normal ventilation air duct 22a between the fourth damper 50d and the end of the partition wall 42. In other words, the supply air duct 24 communicates with the normal ventilation air duct 22a, the exhaust air duct 22, and the exhaust port 16 via the second bypass air duct 30 and the heat exchange air duct 22b on the downstream side of the supply air fan 36.

As a result, during the second exhaust operation, the fourth exhaust flow A2d is blown by the exhaust fan 34 and the supply air fan 36 through the exhaust air duct 22, which includes the outside air intake port 18, the supply air duct 24, the second bypass air duct 30, the heat exchange air duct 22b between the second bypass air duct 30 and the fourth damper 50d, and the normal ventilation air duct 22a, and is discharged to the outdoors through the exhaust port 16. The portion of the fourth exhaust flow A2d that passes through the supply air duct 24 can also be said to be the supply air flow.

In other words, the air that has passed through the second bypass duct 30 flows back through the heat exchange duct 22b from the second filter 40 to just before the indoor air inlet 14, and then passes through the normal ventilation duct 22a before being exhausted from the exhaust port 16. This allows the airborne particles 92 on the indoor air inlet 14 side of the second filter 40 to be exhausted to the outdoors from the exhaust port 16 through the normal ventilation duct 22a.

The air that has passed through the second bypass air passage 30 does not flow through the heat exchange air passage 22b to the heat exchange unit 32 side, but to the second filter 40 side. This is because the air passage resistance of the heat exchange unit 32 in the heat exchange air passage 22b is smaller on the second filter 40 side than on the heat exchange unit 32 side.

The airflow of the exhaust fan 34 and the supply fan 36 is the maximum airflow that can be set, so that the airborne particles 92 on the second filter 40 can be easily discharged outdoors. Therefore, the amount of airborne particles 92 adhering to the second filter 40 can be reduced or substantially eliminated, so that the frequency of replacing the second filter 40 can be reduced. In addition, when replacing the second filter 40, since there is less airborne particles 92 adhering to the second filter 40, the airborne particles 92 are less likely to fall indoors.

When the first exhaust operation and the second exhaust operation are completed, the control unit 62 resumes the temporarily stopped heat exchange ventilation operation or normal ventilation operation. This makes it possible to automatically remove airborne particles adhering to the first filter 38 and the second filter 40 while the ventilation operation is temporarily suspended without user operation. This reduces the maintenance burden of the ventilation device 10.

When the operation time accumulated by the accumulator 60 exceeds a predetermined time, the controller 62 resets the operation time accumulated by the accumulator 60 to zero. This allows the first discharge operation and the second discharge operation to be performed every time the predetermined time elapses, and allows airborne particles to be removed periodically.

Second Embodiment
The second embodiment differs from the first embodiment in that whether or not to execute the first discharge operation and the second discharge operation is controlled in accordance with the outside air temperature. The following mainly describes the differences from the first embodiment.

Figure 5 is a plan view showing a schematic configuration of the ventilation device 10 of the second embodiment. Figure 5 also shows an example of the operating state of the ventilation device 10 during heat exchange operation. The ventilation device 10 further includes a temperature sensor 66 arranged between the outside air inlet 18 and the heat exchange section 32 in the supply air duct 24. The temperature sensor 66 detects the temperature of the air sucked in from the outside air inlet 18 and supplies the detection result to the control device 48. The detected temperature corresponds to the outdoor air temperature.

The control device 48 further includes an acquisition unit 64. The acquisition unit 64 acquires the air temperature detected by the temperature sensor 66 and supplies the acquired temperature information to the accumulator 60. The accumulator 60 accumulates the operation time of the ventilation operation when the temperature acquired by the acquisition unit 64 is higher than a predetermined temperature, and stops accumulating the operation time of the ventilation operation when the acquired temperature is equal to or lower than the predetermined temperature. The predetermined temperature can be appropriately determined through experiments so that the number of insects adhering to the first filter 38 increases relatively when the outdoor air temperature exceeds the predetermined temperature. The predetermined temperature may differ depending on the country or region, but may be, for example, around 20°C.

This allows the first and second discharge operations to be performed periodically only when the outdoor temperature is relatively high and there are relatively many insects outdoors. Therefore, when there are relatively few insects outdoors, the discharge operation is not performed, and power consumption can be reduced.

The processing of the accumulating unit 60 may be the same as that of the first embodiment. In this case, when the temperature acquired by the acquiring unit 64 is higher than a predetermined temperature, the control unit 62 may perform the first discharge operation and the second discharge operation when the operation time accumulated by the accumulating unit 60 exceeds a first predetermined time. When the acquired temperature is equal to or lower than a predetermined temperature, the control unit 62 may perform the first discharge operation and the second discharge operation when the accumulated operation time exceeds a second predetermined time. The second predetermined time is longer than the first predetermined time. In this modified example, the frequency of the discharge operation can be reduced during periods when there are relatively few insects outdoors, thereby reducing power consumption.

The present disclosure has been described above based on an embodiment. This embodiment is merely an example, and it will be understood by those skilled in the art that various modifications are possible in the combination of each component or each processing process, and that such modifications are also within the scope of the present disclosure.

For example, in the first and second embodiments, in cases where the air passage resistance of the heat exchange section 32 is relatively small, a fifth damper (not shown) may be provided that closes the heat exchange air passage 22b between the second bypass air passage 30 and the heat exchange section 32 during the second exhaust operation. In this case, the fifth damper is controlled by the control section 62 to open the heat exchange air passage 22b between the second bypass air passage 30 and the heat exchange section 32 during the heat exchange operation, normal ventilation operation, and first exhaust operation. In this modified example, the air that has passed through the second bypass air passage 30 can be more reliably directed to the second filter 40 side during the second exhaust operation.

In addition, in the first and second embodiments, the ventilation device 10 does not need to perform the second exhaust operation. In this case, the third damper 50c and the second bypass air passage 30 are not provided, and the fourth damper 50d does not need to be controlled to the third state. In this modified example, the configuration of the ventilation device 10 can be simplified.

In addition, in the first and second embodiments, the normal ventilation air duct 22a may not be provided. In this case, the ventilation device 10 does not perform the normal ventilation operation and the second exhaust operation. The third damper 50c, the fourth damper 50d, the second bypass air duct 30, and the partition wall 42 are also not provided. During the first exhaust operation, the third exhaust flow A2c passes through the indoor intake port 14, the heat exchange air duct 22b, the heat exchange section 32, the exhaust air duct 22, the first bypass air duct 28, the supply air duct 24 between the second damper 50b and the outdoor air intake port 18, and exits to the outdoors through the outdoor air intake port 18. In this modified example, the configuration of the ventilation device 10 can be simplified.

Furthermore, in the first and second embodiments, the control unit 62 may control the fourth damper 50d to the first state during the first exhaust operation. In this case, the third exhaust flow A2c passes through the indoor air inlet 14, the heat exchange air duct 22b, the heat exchange unit 32, the exhaust air duct 22, the first bypass air duct 28, the supply air duct 24 between the second damper 50b and the outdoor air inlet 18, and exits to the outdoors through the outdoor air inlet 18. This modification improves the degree of freedom in the configuration of the ventilation device 10.

In addition, in the first and second embodiments, the heat exchange section 32 may not be provided. In this case, the ventilation device 10 does not perform the heat exchange operation and the second exhaust operation. The normal ventilation air duct 22a and the heat exchange air duct 22b are configured as an integrated exhaust air duct 22. The third damper 50c, the fourth damper 50d, the second bypass air duct 30, and the partition wall 42 are also not provided. During normal ventilation operation, the second exhaust flow A2b passes through the indoor air inlet 14 and the exhaust air duct 22, and exits to the outdoors through the outdoor air inlet 18. The supply air flow A1 passes through the outdoor air inlet 18 and the supply air duct 24, and exits to the indoors through the supply air duct 20. During the first exhaust operation, the third exhaust flow A2c passes through the indoor air inlet 14, the exhaust air duct 22, the first bypass air duct 28, the supply air duct 24 between the second damper 50b and the outdoor air inlet 18, and exits to the outdoors through the outdoor air inlet 18. In this modified example, the configuration of the ventilation device 10 can be simplified.

An overview of one aspect of the present disclosure is as follows: A ventilation device (10) according to an embodiment of the present disclosure includes an exhaust air duct (22) that connects an indoor air inlet (14) and an exhaust air duct (16), an air supply air duct (24) that connects an outdoor air inlet (18) and an air supply port (20), a first filter (38) disposed in the air supply air duct (24), a first bypass air duct (28) that can direct air passing through the exhaust air duct (22) to a position between the first filter (38) and the air supply port (20) in the air supply air duct (24), and a first air duct switching unit (44) that can switch between a first state in which the first bypass air duct (28) is closed and a second state in which the first bypass air duct (28) is opened and air that has passed through the first bypass air duct (28) from the exhaust air duct (22) flows back into the air supply air duct (24) from the first filter (38) to the outdoor air inlet (18).

The ventilation device (10) may further include a heat exchange section (32) that exchanges heat between the air passing through the exhaust air duct (22) and the air passing through the supply air duct (24), and the first bypass air duct (28) may be capable of directing the air passing through the exhaust air duct (22) to a position in the supply air duct (24) between the first filter (38) and the heat exchange section (32).

The ventilation device (10) may further include a control unit (62) that controls the first air passage switching unit (44) to a first state during ventilation operation and controls the first air passage switching unit (44) to a second state during first exhaust operation.

The ventilation device (10) may further include an exhaust fan (34) arranged between the heat exchange section (32) and the exhaust port (16) in the exhaust air duct (22) and directing air from the indoor air inlet (14) to the exhaust port (16), and a second air duct switching section (46). The exhaust air duct (22) may have a normal ventilation air duct (22a) that connects the indoor air inlet (14) to the exhaust fan (34) without passing through the heat exchange section (32), and a heat exchange air duct (22b) that connects the indoor air inlet (14) to the exhaust fan (34) through the heat exchange section (32). The second air passage switching section (46) may be switchable between a first state in which the air sucked through the indoor air inlet (14) is passed through the heat exchange air passage (22b) and a second state in which the air sucked through the indoor air inlet (14) is passed through the normal ventilation air passage (22a).

The ventilation device (10) may further include a control unit (62) that controls the first air passage switching unit (44) to a first state and the second air passage switching unit (46) to a first state during heat exchange ventilation operation, controls the first air passage switching unit (44) to the first state and the second air passage switching unit (46) to the second state during normal ventilation operation, and controls the first air passage switching unit (44) to the second state and the second air passage switching unit (46) to the second state during first exhaust operation.

The ventilation device (10) may further include a second filter (40) arranged between the heat exchange section (32) and the indoor air inlet (14) in the heat exchange air duct (22b), an air supply fan (36) arranged between the heat exchange section (32) and the air supply port (20) in the air supply duct (24) and configured to flow air from the outdoor air inlet (18) to the air supply port (20), and a second bypass air duct (30) capable of flowing air from a position between the air supply fan (36) and the air supply port (20) in the air supply duct (24) to a position between the second filter (40) and the heat exchange section (32) in the heat exchange air duct (22b). The second air duct switching section (46) may close the second bypass air duct (30) in the first state and the second state. The second air passage switching unit (46) may be further switchable to a third state in which the second bypass air passage (30) is opened and the indoor air inlet (14) is closed, and the air supplied from the supply air passage (24) and passed through the second bypass air passage (30) is caused to flow back into the heat exchange air passage (22b) from the second filter (40) to the indoor air inlet (14), and the backflowing air is discharged from the exhaust port (16) through the normal ventilation air passage (22a).

The ventilation device (10) may further include a control unit (62) that controls the first air path switching unit (44) to a first state and the second air path switching unit (46) to a first state during heat exchange ventilation operation, controls the first air path switching unit (44) to a first state and the second air path switching unit (46) to a second state during normal ventilation operation, controls the first air path switching unit (44) to a second state and the second air path switching unit (46) to a second state during first exhaust operation, and controls the first air path switching unit (44) to a first state and the second air path switching unit (46) to a third state during second exhaust operation.

The ventilation device (10) may further include an accumulating unit (60) that accumulates the operation time of the ventilation operation. When the accumulated operation time exceeds a predetermined time, the control unit (62) may temporarily suspend the ventilation operation and perform the first exhaust operation.

The ventilation device (10) may further include an acquisition unit (64) that acquires the temperature of the air drawn in through the outside air inlet (18). The accumulation unit (60) may accumulate the operation time of the ventilation operation when the acquired temperature is higher than a predetermined temperature, and may stop accumulating the operation time of the ventilation operation when the acquired temperature is equal to or lower than the predetermined temperature.

The ventilation device (10) may further include an exhaust fan (34) disposed in the exhaust air duct (22) and directing air from the indoor air inlet (14) to the exhaust outlet (16). The control unit (62) may set the air volume of the exhaust fan (34) to the maximum air volume that can be set during the first exhaust operation.

The ventilation device (10) may further include an accumulating unit (60) that accumulates the operating time of the heat exchange ventilation operation and the normal ventilation operation. When the accumulated operating time exceeds a predetermined time, the control unit (62) may temporarily suspend the heat exchange ventilation operation or the normal ventilation operation that is being performed, and perform the first exhaust operation and the second exhaust operation in turn.

10...ventilation device, 14...indoor air intake, 16...exhaust air outlet, 18...outdoor air intake, 20...air intake, 22...exhaust air duct, 22a...normal ventilation air duct, 22b...heat exchange air duct, 24...air intake duct, 28...first bypass air duct, 30...second bypass air duct, 32...heat exchange section, 34...exhaust fan, 36...air intake fan, 38...first filter, 40...second filter, 44...first air duct switching section, 46...second air duct switching section, 50a...first damper, 50b...second damper, 50c...third damper, 50d...fourth damper, 60...integration section, 62...control section, 64...acquisition section, 66...temperature sensor.

Claims (11)

an exhaust air duct communicating between the indoor intake port and the exhaust port;
an air supply duct communicating between the outside air inlet and the air supply port;
A first filter disposed in the air supply passage;
a first bypass air passage capable of directing air passing through the exhaust air passage to a position in the intake air passage between the first filter and the intake port;
a first air passage switching unit capable of switching between a first state in which the first bypass air passage is closed and a second state in which the first bypass air passage is opened and air that has passed through the first bypass air passage from the exhaust air passage is caused to flow back into the supply air passage from the first filter to the outside air intake port;
A ventilation device comprising: a heat exchange unit that exchanges heat between air passing through the exhaust air passage and air passing through the intake air passage,
The first bypass air passage is capable of directing air passing through the exhaust air passage to a position in the supply air passage between the first filter and the heat exchange unit.
2. The ventilation device of claim 1. A control unit is further provided that controls the first air-path switching unit to a first state during a ventilation operation and controls the first air-path switching unit to a second state during a first exhaust operation.
3. A ventilation device according to claim 1 or 2. an exhaust fan disposed between the heat exchange unit and the exhaust port in the exhaust air duct and configured to blow air from the indoor air inlet to the exhaust port;
A second air passage switching unit;
Further equipped with
The exhaust air duct includes a normal ventilation air duct that communicates from the indoor air inlet to the exhaust fan without passing through the heat exchange unit, and a heat exchange air duct that communicates from the indoor air inlet to the exhaust fan through the heat exchange unit,
The second air passage switching unit is capable of switching between a first state in which the air sucked through the indoor air inlet is passed through the heat exchange air passage and a second state in which the air sucked through the indoor air inlet is passed through the normal ventilation air passage.
3. A ventilation device according to claim 2. During a heat exchange operation, the first air-passage switching unit is controlled to a first state, and the second air-passage switching unit is controlled to a first state,
During normal ventilation operation, the first air-path switching unit is controlled to a first state and the second air-path switching unit is controlled to a second state;
Further comprising a control unit that controls the first air-path switching unit to the second state and the second air-path switching unit to the second state during a first discharge operation.
5. A ventilation system according to claim 4. A second filter disposed between the heat exchange unit and the indoor air inlet in the heat exchange air duct;
an intake fan disposed between the heat exchange unit and the intake port in the intake air duct to flow air from the outside air inlet to the intake port;
a second bypass air passage capable of flowing air from a position between the air supply fan and the air supply port in the air supply air passage to a position between the second filter and the heat exchange unit in the heat exchange air passage;
Further equipped with
the second air-flow path switching unit closes the second bypass air-flow path in a first state and a second state;
The second air passage switching unit can be further switched to a third state in which the second bypass air passage is opened and the indoor air inlet is closed, the air supplied from the supply air passage and passing through the second bypass air passage is caused to flow back into the heat exchange air passage from the second filter to the indoor air inlet, and the backflowing air is caused to flow through the normal ventilation air passage and discharged from the exhaust port.
5. A ventilation system according to claim 4. During a heat exchange operation, the first air-passage switching unit is controlled to a first state, and the second air-passage switching unit is controlled to a first state,
During normal ventilation operation, the first air-path switching unit is controlled to a first state and the second air-path switching unit is controlled to a second state;
During a first discharge operation, the first air-path switching unit is controlled to a second state and the second air-path switching unit is controlled to a second state;
Further comprising a control unit that controls the first air-path switching unit to a first state and the second air-path switching unit to a third state during a second discharge operation.
7. A ventilation device according to claim 6. An integrating unit that integrates an operation time of the ventilation operation is further provided,
When the accumulated operation time exceeds a predetermined time, the control unit temporarily stops the ventilation operation and performs the first discharge operation.
4. A ventilation device according to claim 3. An acquisition unit for acquiring a temperature of the air drawn in through the outside air inlet,
The integrating unit integrates an operation time of the ventilation operation when the acquired temperature is higher than a predetermined temperature, and stops integrating the operation time of the ventilation operation when the acquired temperature is equal to or lower than the predetermined temperature.
9. A ventilation device according to claim 8. An exhaust fan is further provided, the exhaust fan being disposed in the exhaust air duct and configured to blow air from the indoor air inlet to the exhaust outlet.
The control unit sets the air volume of the exhaust fan to a settable maximum air volume during the first exhaust operation.
4. A ventilation device according to claim 3. An integrating unit that integrates the operation times of the heat exchange ventilation operation and the normal ventilation operation is further provided,
When the accumulated operation time exceeds a predetermined time, the control unit temporarily suspends the heat exchange ventilation operation or the normal ventilation operation being executed, and sequentially performs the first exhaust operation and the second exhaust operation.
8. A ventilation device according to claim 7.

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