JP7522962B2 - Ventilation system - Google Patents

Description

The present invention relates to a ventilation device.

Conventionally, as one type of ventilation device that exchanges indoor air with outdoor air, a heat exchange type ventilation device that reduces the loss of thermal energy by recovering part of the thermal energy contained in the exhaust air flow with the intake air flow (for example, Patent Document 1). Below, this heat exchange type ventilation device will be described with reference to Figure 7.

As shown in FIG. 7, the heat exchange ventilation device 900 includes an intake air duct 810, an exhaust air duct 820, an intake air blower 830, an exhaust air blower 840, and a heat exchange element 850.

The supply air duct 810 is an air duct for transporting outdoor air indoors. The exhaust air duct 820 is an air duct for transporting indoor air outdoors. The supply air blower 830 generates an supply air flow in the supply air duct 810. The exhaust air blower 840 generates an exhaust air flow in the exhaust air duct 820. The heat exchange element 850 exchanges heat between the supply air flow and the exhaust air flow, and recovers a portion of the thermal energy contained in the exhaust air flow with the supply air flow. The heat exchange element 850 constitutes a portion of the supply air duct 810 and the exhaust air duct 820.

With this configuration, the ventilation device 900 generates an intake air flow and an exhaust air flow, and ventilates the indoor space with heat recovery, so that the indoor space can obtain clean air quality while minimizing the loss of thermal energy.

JP 2008-45795 A

In conventional ventilation systems like this, when ventilating a space with many people entering and exiting, such as a restaurant, it was not possible to adjust the ventilation volume in response to an increase or decrease in the number of people in the room. This resulted in issues such as an inability to provide appropriate ventilation in response to an increase or decrease in the number of people in the room, resulting in an excessive ventilation volume for the number of people in the room, which reduces energy efficiency, or an insufficient ventilation volume for the number of people in the room, which deteriorates the air quality.

The present invention aims to solve the above-mentioned problems of the conventional technology and provide a ventilation device that can provide appropriate ventilation in response to an increase or decrease in the number of people in a room.

In order to achieve this object, a ventilation device according to one embodiment of the present invention is a ventilation device comprising: an intake air duct for transporting air from the outdoors to an indoor space; an exhaust air duct for transporting air from the indoor space to the outdoors; an intake air blower that generates an airflow in the intake air duct; an exhaust air blower that generates an airflow in the exhaust air duct; a carbon dioxide concentration measurement unit that measures the concentration of carbon dioxide contained in the air passing through the exhaust air duct; and a control unit that controls the operation of the intake air blower and the exhaust air blower, wherein the control unit comprises: a number of occupants estimation unit that estimates the number of people present in the indoor space from the concentration of carbon dioxide measured by the carbon dioxide concentration measurement unit; a ventilation volume calculation unit that calculates the required ventilation volume for the indoor space based on the number of occupants estimated by the number of occupants estimation unit; a timer unit that acquires the current date and time; and a memory unit that stores the number of occupants estimated by the number of occupants estimation unit and the time at which the number of occupants was estimated . In addition, the control unit controls the operation of the supply air blower and the exhaust air blower in accordance with the required ventilation volume calculated by the ventilation volume calculation unit , and when it determines that the current time is within a predetermined time, it controls the operation of the supply air blower and the exhaust air blower so that the required ventilation volume corresponds to the maximum value until the time when the number of people stored in the memory unit reaches its maximum value , thereby achieving the desired purpose.

The present invention allows for appropriate ventilation in response to changes in the number of people in an indoor space.

FIG. 1 is a block diagram showing a configuration of a ventilation device according to an embodiment. FIG. 2 is a block diagram showing a detailed configuration of the control unit of the ventilation apparatus of FIG. FIG. 3 is a flowchart showing the operation of the control unit. FIG. 4 is a flowchart showing the operation of the control unit. FIG. 5 is a flowchart showing the operation of the control unit. FIG. 6 is a flowchart showing the operation of the control unit. FIG. 7 is a block diagram showing the configuration of a conventional ventilation device.

Below, the embodiments for carrying out the present invention will be described with reference to the attached drawings. In the embodiments and the 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 in each drawing are omitted.

The configuration of the ventilation device 100 of the present invention will be described using FIG. 1. FIG. 1 is a block diagram showing the configuration of the ventilation device 100.

The ventilation device 100 is a type of air blowing device that has an air supply function that transports outdoor air to the indoor space 200, and an exhaust function that transports air from the indoor space 200 to the outdoors. The ventilation device 100 has an air supply duct 10, an exhaust duct 12, an air supply blower 20, an exhaust blower 22, a carbon dioxide concentration measuring unit 30, an operation unit 40, and a control unit 50.

The supply air duct 10 is an air duct for transporting outdoor air indoors. The supply air duct 10 connects a duct (not shown) to the indoor space 200, thereby communicating between the outdoors and the indoors. The exhaust air duct 12 is an air duct for transporting indoor air outdoors. The exhaust air duct 12 connects a duct (not shown) to the indoor space 200, thereby communicating between the outdoors and the indoors.

The intake air blower 20 is disposed on the intake air duct 10 and generates an intake air flow. The intake air blower 20 includes an intake air fan (not shown) and an intake air motor (not shown) that rotatably supports the intake air fan.

The exhaust blower 22 is disposed on the exhaust air duct 12 and generates an exhaust flow. The exhaust blower 22 includes an exhaust fan (not shown) and an exhaust motor (not shown) that rotatably supports the exhaust fan.

In this embodiment, the intake air blower 20 and the exhaust air blower 22 are provided separately, but this is not limited to the above. For example, the intake air fan may be rotatably supported on one end of a double-shaft motor, and the exhaust air fan may be rotatably supported on the other end. Also, a motor on one side may be combined with a gear using well-known technology to enable the intake air fan and the exhaust air fan to rotate.

The carbon dioxide concentration measuring unit 30 measures the concentration of carbon dioxide contained in the air passing through the exhaust air duct 12. In other words, the carbon dioxide concentration measuring unit 30 measures the concentration of carbon dioxide contained in the indoor space 200. The carbon dioxide concentration measuring unit 30 is disposed upstream of the exhaust blower 22 in the exhaust air duct 12. An example of the carbon dioxide concentration measuring unit 30 is a CO2 sensor. Note that in this embodiment, the carbon dioxide concentration measuring unit 30 is disposed upstream of the exhaust blower 22, but it may be disposed downstream of the exhaust blower 22.

The operation unit 40 is a portion provided with a switch that allows the user to select the operation type of the ventilation device 100. The operation type refers to, for example, turning the operation of the ventilation device 100 ON/OFF. The type of switch may be a mechanical type that uses the elastic force of a spring or the like, or a capacitance type that uses the change in capacitance between the fingertip and a conductive film. The operation unit 40 is disposed on the outer peripheral surface of the ventilation device 100.

The control unit 50 controls the operation of the intake air blower 20 and the exhaust air blower 22, and overall control of the ventilation device 100. The control unit 50 will be described with reference to FIG. 2. FIG. 2 is a functional block diagram that shows the control unit 50 in outline. Each functional block shown in FIG. 2 can be realized in hardware by elements and mechanical devices such as a CPU (Central Processing Unit), and in software by a computer program, but here, functional blocks realized by the cooperation of these are depicted. Therefore, those skilled in the art who have read this specification will understand that these functional blocks can be realized in various ways by combining hardware and software.

The control unit 50 is placed in an optimal location inside the ventilation device 100, as shown in FIG. 1.

The control unit 50 transmits control information to the supply air blower 20 and the exhaust air blower 22 via a wired or wireless signal transmission path (not shown).

The control unit 50 receives information from the carbon dioxide concentration measurement unit 30 and the operation unit 40 via a wired or wireless signal transmission path (not shown).

The control unit 50 includes an operation type information acquisition unit 60, a CO2 concentration acquisition unit 62, a number of people occupancy estimation unit 64, a ventilation volume calculation unit 66, a timing unit 68, a memory unit 70, a first operation control unit 72, and a second operation control unit 74.

The driving type information acquisition unit 60 acquires driving type information from the operation unit 40.

The CO2 concentration acquisition unit 62 acquires the carbon dioxide concentration from the carbon dioxide concentration measurement unit 30.

The occupancy estimation unit 64 estimates the number of people present in the indoor space 200 based on the carbon dioxide concentration acquired by the CO2 concentration acquisition unit 62. For example, if one person is present in the indoor space 200, it is assumed that carbon dioxide increases at 50 [g/h] per unit time. In this case, if the carbon dioxide in the indoor space 200 measured by the carbon dioxide concentration measurement unit 30 increases at 250 [g/h], it can be estimated that there are 250 [g/h] ÷ 50 [g/h] = 5 people present in the indoor space 200. The carbon dioxide concentration can also be expressed in units of [g/m3] or [ppm]. In this case, the size (volume) of the indoor space 200 is stored in advance in the control unit 50 before the operation of the ventilation device 100.

The ventilation volume calculation unit 66 calculates the required ventilation volume based on the number of occupants in the indoor space 200 estimated by the occupancy estimation unit 64. For example, assume that the required ventilation volume per person in the indoor space 200 is 30 [m3/h]. In this case, if the number of people estimated by the occupancy estimation unit 64 is 5 people, the ventilation volume calculation unit 66 calculates the required ventilation volume for the indoor space 200 as 30 [m3/h] x 5 people = 150 [m3/h].

The clock unit 68 acquires information on the current date and time. The current date and time can be set at any time regardless of the operation type of the ventilation device 100. The setting method may be manual setting by the user or automatic setting by receiving radio waves carrying time information.

The memory unit 70 stores data referenced or updated by the control unit 50. For example, it may store a control algorithm related to the operation of the supply air blower 20 and the exhaust air blower 22 corresponding to the operation type of the ventilation device 100. In addition, it may store the number of people estimated by the number of people estimating unit 64 and the current time measured by the timing unit 68 (the time when the number of people estimated by the number of people estimating unit 64) in association with each other.

The first operation control unit 72 controls the operation of the air supply blower 20.

The second operation control unit 74 controls the operation of the exhaust blower 22.

The above is the configuration of the ventilation device 100.

Next, an example of the operation of the ventilation device 100 of the present invention will be described. The operation described below is an operation performed when a user operates to stop operation, and is started at the timing when the operation is performed or at a preset timing.

The operation of the ventilation device 100 will be described with reference to Figures 3 to 6. Figures 3 to 6 are flowcharts showing the operation control of the supply air blower 20 and the exhaust air blower 22 according to the number of people in the indoor space 200.

When the operation type information acquisition unit 60 acquires a signal indicating that the ventilation device 100 is in operation from the operation unit 40, the control unit 50 controls the first operation control unit 72 and the second operation control unit 74 to start operation of the supply air blower 20 and the exhaust air blower 22 (step S10). In step S10, the operation of the supply air blower 20 and the exhaust air blower 22 is controlled so that the ventilation air volume is Q-0. The ventilation air volume Q0 is the minimum ventilation air volume. Here, the minimum ventilation air volume is the ventilation air volume required when there is one person in the indoor space 200, and is, for example, Q0 = 30 [m3/h].

When the supply air blower 20 and exhaust air blower 22 start operating, the control unit 50 acquires the carbon dioxide concentration measured by the carbon dioxide concentration measurement unit 30 using the CO2 concentration acquisition unit 62 (step S12). It is preferable to measure the carbon dioxide concentration at a fixed sampling time within a specified period of time. For example, if sampling is performed for two minutes at a sampling time interval of two seconds, 60 carbon dioxide concentration measurement data are obtained, and the arithmetic average of these data is acquired as the carbon dioxide concentration of the indoor space 200 by the CO2 concentration acquisition unit 62. This suppresses carbon dioxide concentration measurement errors and enables highly accurate estimation of the number of people present.

When the CO2 concentration acquisition unit 62 acquires the carbon dioxide concentration in the indoor space 200, the control unit 50 estimates the number of people occupying the room P1 using the number of people occupying estimation unit 64 (step S14).

As described above, the method for estimating the number of occupants P1 is as follows: if there is one person in the indoor space 200 and carbon dioxide increases at X [g/h] per unit time, and the carbon dioxide in the indoor space 200 measured by the carbon dioxide concentration measuring unit 30 increases at Y [g/h], then the number of occupants P1 in the indoor space 200 is estimated using the formula Y [g/h] ÷ X [g/h].

Once the number of people occupancy estimation unit 64 has estimated the number of people occupancy P1, the control unit 50 calculates the required ventilation volume Q1 (step S16). The required ventilation volume Q1 can be calculated, for example, as Q1 = Q0 x P1.

When the required ventilation volume Q1 is calculated by the ventilation volume calculation unit 66, the control unit 50 associates the number of people P1 estimated in step S14 with the time T1 at which P1 was estimated and stores them in the memory unit 70 (step S18).

When the memory unit 70 stores the number of occupants P1 and the information on the time T1 at which P1 was estimated, the control unit 50 controls the operation of the supply air blower 20 and the exhaust air blower 22 using the first operation control unit 72 and the second operation control unit 74 so that the ventilation air volume (supply air volume and exhaust air volume) becomes Q1 (step S20).

When the operation of the supply air blower 20 and the exhaust air blower 22 is controlled so that the ventilation air volume becomes Q1, the control unit 50 judges whether the operation type information acquisition unit 60 has received a signal to turn off the operation of the ventilation device 100 from the operation unit 40. When the operation type information acquisition unit 60 receives a signal to turn off the operation of the ventilation device 100 (Y in step S22), the control unit 50 controls the first operation control unit 72 and the second operation control unit 74 to stop the operation of the supply air blower 20 and the exhaust air blower 22 (step S24). If the operation type information acquisition unit 60 does not receive a signal to turn off the operation of the ventilation device 100, step S24 is skipped and the control unit 50 continues the operation of the ventilation device 100 (N, (1) in step S22).

When the operation of the ventilation device 100 continues, the control unit 50 acquires the carbon dioxide concentration measured by the carbon dioxide concentration measurement unit 30 using the CO2 concentration acquisition unit 62 (step S26). It is preferable to measure the carbon dioxide concentration at a fixed sampling time within a specified period of time. For example, if sampling is performed for two minutes at a sampling time interval of two seconds, 60 carbon dioxide concentration measurement data are obtained, and the arithmetic average of these data is acquired by the CO2 concentration acquisition unit 62 as the carbon dioxide concentration of the indoor space 200. This suppresses carbon dioxide concentration measurement errors and enables highly accurate estimation of the number of people present.

When the CO2 concentration acquisition unit 62 acquires the carbon dioxide concentration in the indoor space 200, the control unit 50 estimates the number of people P2 in the room using the number of people estimation unit 64 (step S28). The method of estimating the number of people P2 in the room is the same as the process in step S14.

Once the number of people occupancy estimation unit 64 has estimated the number of people occupancy P2, the control unit 50 calculates the required ventilation volume Q2 using the ventilation volume calculation unit 66 (step S30). The required ventilation volume Q2 can be calculated, for example, as Q2 = Q0 x P2.

When the required ventilation volume Q2 is calculated by the ventilation volume calculation unit 66, the control unit 50 associates the number of people P2 estimated in step S28 with the time T2 at which P2 was estimated and stores them in the memory unit 70 (step S32).

When the memory unit 70 stores the number of occupants P2 and the information on the time T2 at which P2 was estimated, the control unit 50 controls the operation of the supply air blower 20 and the exhaust air blower 22 using the first operation control unit 72 and the second operation control unit 74 so that the ventilation air volume (supply air volume and exhaust air volume) becomes Q2 (step S34).

When the operation of the supply air blower 20 and the exhaust air blower 22 is controlled so that the ventilation air volume becomes Q1, the control unit 50 judges whether the operation type information acquisition unit 60 has received a signal to turn off the operation of the ventilation device 100 from the operation unit 40. When the operation type information acquisition unit 60 receives a signal to turn off the operation of the ventilation device 100 (Y, (2) in step S36), the control unit 50 controls the first operation control unit 72 and the second operation control unit 74 to stop the operation of the supply air blower 20 and the exhaust air blower 22 (step S24). When the operation type information acquisition unit 60 does not receive a signal to turn off the operation of the ventilation device 100 (N in step S36), step S24 is skipped and the control unit 50 continues the operation of the ventilation device 100.

When the operation of the ventilation device 100 continues, the control unit 50 determines whether the number of people P1 is greater than the number of people P2. If the number of people P1 is greater than the number of people P2 (Y in step S38), the control unit 50 stores the maximum number of people Pmax = P1 and the maximum number of people time Tmax = T1 in the memory unit 70. If the number of people P1 is equal to or less than the number of people P2 (N in step S38), step S40 is skipped and the control unit 50 stores the maximum number of people Pmax = P2 and the maximum number of people time Tmax = T2 in the memory unit 70.

When the data of the maximum number of occupants Pmax and the maximum number of occupants time Tmax are stored in the memory unit 70, the control unit 50 determines whether the current time is equal to or less than a predetermined threshold value for the maximum number of occupants time Tmax. For example, if the predetermined threshold value is 30 minutes and the maximum number of occupants time Tmax is 12:30, the control unit 50 determines whether the current time is greater than 12:00. If the current time is equal to or less than the predetermined threshold value for the maximum number of occupants time Tmax (Y, (3) in step S44), the control unit 50 calculates the required ventilation volume Qmax using the ventilation volume calculation unit 66 (step S46). The calculation formula for the required ventilation volume Qmax is, for example, Qmax = Q0 x Pmax.

When the required ventilation volume Qmax is calculated by the ventilation volume calculation unit 66, the control unit 50 controls the operation of the supply air blower 20 and the exhaust air blower 22 using the first operation control unit 72 and the second operation control unit 74 so that the ventilation air volume (supply air volume and exhaust air volume) becomes Qmax (step S48).

When the operation of the supply air blower 20 and the exhaust air blower 22 is controlled so that the ventilation air volume becomes Qmax, the control unit 50 judges whether the operation type information acquisition unit 60 has received a signal to turn off the operation of the ventilation device 100 from the operation unit 40. When the operation type information acquisition unit 60 receives a signal to turn off the operation of the ventilation device 100 (Y, (5) in step S50), the control unit 50 controls the first operation control unit 72 and the second operation control unit 74 to stop the operation of the supply air blower 20 and the exhaust air blower 22 (step S24). When the operation type information acquisition unit 60 does not receive a signal to turn off the operation of the ventilation device 100 (N in step S50), step S24 is skipped and the control unit 50 continues the operation of the ventilation device 100.

If the current time is greater than the predetermined threshold value for the maximum occupancy time Tmax (N in step S44, (4)), steps S46 to S50 are skipped and the control unit 50 continues to operate the ventilation device 100.

When the operation of the ventilation device 100 continues, the control unit 50 acquires the carbon dioxide concentration measured by the carbon dioxide concentration measurement unit 30 using the CO2 concentration acquisition unit 62 (step S52). It is preferable to measure the carbon dioxide concentration at a fixed sampling time within a specified time. For example, if sampling is performed for two minutes at a sampling time interval of two seconds, 60 carbon dioxide concentration measurement data are obtained, and the arithmetic average of these data is acquired by the CO2 concentration acquisition unit 62 as the carbon dioxide concentration of the indoor space 200. This suppresses carbon dioxide concentration measurement errors and enables highly accurate estimation of the number of people present.

When the CO2 concentration acquisition unit 62 acquires the carbon dioxide concentration in the indoor space 200, the control unit 50 estimates the number of people P1 in the room using the number of people estimation unit 64 (step S54). The method of estimating the number of people P1 is the same as in step S14.

Once the number of people occupancy estimation unit 64 has estimated the number of people occupancy P1, the control unit 50 calculates the required ventilation volume Q1 using the ventilation volume calculation unit 66 (step S56). The required ventilation volume Q1 can be calculated, for example, as Q1 = Q0 x P1.

When the required ventilation volume Q1 is calculated by the ventilation volume calculation unit 66, the control unit 50 associates the number of people P1 estimated in step S54 with the time T1 at which P1 was estimated and stores them in the memory unit 70 (step S58).

When the memory unit 70 stores the number of occupants P1 and the information on the time T1 at which P1 was estimated, the control unit 50 controls the operation of the supply air blower 20 and the exhaust air blower 22 using the first operation control unit 72 and the second operation control unit 74 so that the ventilation air volume (supply air volume and exhaust air volume) becomes Q1 (step S60).

When the operation of the supply air blower 20 and the exhaust air blower 22 is controlled so that the ventilation air volume becomes Q1, the control unit 50 judges whether the operation type information acquisition unit 60 has received a signal to turn off the operation of the ventilation device 100 from the operation unit 40. When the operation type information acquisition unit 60 receives a signal to turn off the operation of the ventilation device 100 (Y, (6) of step S62), the control unit 50 controls the first operation control unit 72 and the second operation control unit 74 to stop the operation of the supply air blower 20 and the exhaust air blower 22 (step S24). When the operation type information acquisition unit 60 does not receive a signal to turn off the operation of the ventilation device 100 (N, (7) of step S62), step S24 is skipped and the control unit 50 continues the operation of the ventilation device 100.

When the operation of the ventilation device 100 continues, the control unit 50 determines whether the number of people P1 is greater than the number of people P2. If the number of people P1 is greater than the number of people P2 (Y in step S66), the control unit 50 stores the maximum number of people Pmax = P1 and the maximum number of people time Tmax = T1 in the memory unit 70. If the number of people P1 is equal to or less than the number of people P2 (N in step S68), step S66 is skipped and the control unit 50 stores the maximum number of people Pmax = P2 and the maximum number of people time Tmax = T2 in the memory unit 70.

When the data of the maximum number of people Pmax and the maximum number of people time Tmax is stored in the memory unit 70, the control unit 50 judges whether the current time is equal to or less than a predetermined threshold value for the maximum number of people time Tmax. For example, if the predetermined threshold value is 30 minutes and the maximum number of people time Tmax is 12:30, the control unit 50 judges whether the current time is greater than 12:00. If the current time is equal to or less than the predetermined threshold value for the maximum number of people time Tmax (Y, (9) of step S70), the control unit 50 proceeds to step S46 and executes the processes from step S46 onwards. If the current time is greater than the predetermined threshold value for the maximum number of people time Tmax (N, (8) of step S70), the control unit 50 proceeds to step S26 and executes the processes from step S26 onwards.

The above operation is just one example, and various modifications are possible.

The above is an explanation of the operation control of the supply air blower 20 and the exhaust air blower 22 according to the number of people in the indoor space 200.

The ventilation device 100 can estimate the number of people present by measuring the concentration of carbon dioxide contained in the air in the indoor space 200 with the carbon dioxide concentration measuring unit 30, and calculate the required ventilation volume based on the estimated value. This is expected to have the effect of suppressing the possibility of a decrease in energy efficiency due to excessive ventilation for the number of people present, and the possibility of insufficient ventilation due to insufficient ventilation for the number of people present.

In addition, the time when the number of people in the room is at its maximum can be stored, and the required ventilation volume when the number of people in the room is at its maximum can be set in advance from a time a predetermined threshold time earlier than the time when the number of people in the room is at its maximum. This is expected to have the effect of suppressing the increase in carbon dioxide concentration compared to setting the required ventilation volume after the time when the number of people in the room is at its maximum.

The present disclosure has been described above based on an embodiment. This embodiment is merely an example, and those skilled in the art will understand 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. In the above-mentioned embodiment, content for which such design changes are possible is explained using notations such as "in the embodiment" or "in the embodiment," but this does not mean that design changes are not permitted for content without such notation.

The following describes the modified examples. In the drawings and description of the modified examples, the same components and members as those in the embodiment are given the same reference numerals. Explanations that overlap with the embodiment will be omitted as appropriate, and the description will focus on the configurations that differ from the embodiment.

The ventilation device 100 may be a heat exchange type ventilation device equipped with a heat exchange element that exchanges heat between the air passing through the intake air duct 10 and the air passing through the exhaust air duct 12. By forming a part of the heat exchange element in the intake air duct 10 and the exhaust air duct 12, the air passing through the intake air duct 10 can recover a part of the thermal energy contained in the air passing through the exhaust air duct 12 and return it to the indoor space 200. As a result, when an air conditioning device such as an air conditioner is used in combination, the amount of thermal energy lost through ventilation is suppressed, thereby reducing the load on the air conditioning device and increasing the energy efficiency of the entire air conditioning system composed of the ventilation device 100 and the air conditioning device.

In addition, the ventilation device 100 may be configured to have multiple units arranged in the indoor space 200. For example, if the ventilation volume of the ventilation device 100 is not sufficient for the size of the indoor space 200, the ventilation volume can be increased by arranging multiple ventilation devices 100. In this case, a control device that controls the multiple ventilation devices 100 in an integrated manner may be provided in addition to the control unit 50, so that the multiple ventilation devices 100 can be controlled individually. For example, in the indoor space 200, ventilation is focused on places where people are concentrated (places with high carbon dioxide concentrations) while at the same time suppressing ventilation in places where people are not concentrated (places with low carbon dioxide concentrations). This is expected to optimize the ventilation operation of the multiple ventilation devices 100 and increase energy efficiency.

The ventilation device 100 may be installed on the ceiling surface of the indoor space 200, but may also be installed near the floor surface of the indoor space 200. Carbon dioxide is heavier than air, so by placing the ventilation device 100 at a low position, such as near the floor surface, it is expected that the accuracy of measuring carbon dioxide by the carbon dioxide concentration measuring unit 30 will be improved.

The supply air volume and exhaust air volume do not have to be equal. For example, the indoor space 200 can be maintained at a positive pressure by controlling the supply air blower 20 and the exhaust air blower 22 so that the supply air volume is greater than the exhaust air volume while still satisfying the required ventilation volume. This is expected to have the effect of reducing the occurrence of air leaks and the possibility of foreign matter such as pollen entering from outdoors.

The ventilation device according to the present invention is capable of providing appropriate ventilation in response to an increase or decrease in the number of people in an indoor space, and is therefore useful as a ventilation device for ventilating spaces where an unspecified number of people enter and exit, such as restaurants.

REFERENCE SIGNS LIST 10 Intake air duct 12 Exhaust air duct 20 Intake air blower 22 Exhaust air blower 30 Carbon dioxide concentration measuring unit 40 Operation unit 50 Control unit 60 Operation type information acquiring unit 62 CO2 concentration acquiring unit 64 Number of people estimating unit 66 Ventilation amount calculating unit 68 Time measuring unit 70 Storage unit 72 First operation control unit 74 Second operation control unit 100 Ventilation device 200 Indoor space

Claims (1)

an air supply duct for transporting air from the outdoors to the indoor space;
an exhaust air duct for transporting air from the indoor space to the outdoor space;
an air supply fan that generates an air flow in the air supply duct;
an exhaust fan that generates an airflow in the exhaust air duct;
a carbon dioxide concentration measuring unit for measuring a concentration of carbon dioxide contained in air passing through the exhaust air duct;
A control unit that controls the operation of the intake air blower and the exhaust air blower;
A ventilation device comprising:
The control unit is
an occupancy estimation unit that estimates the number of people present in the indoor space from the concentration of carbon dioxide measured by the carbon dioxide concentration measurement unit;
a ventilation amount calculation unit that calculates a required ventilation amount for the indoor space according to the number of occupants estimated by the number of occupants estimation unit;
A clock unit for acquiring the current date and time;
a storage unit that stores the number of people estimated by the number-of-people estimation unit and the time when the number of people was estimated,
controlling operations of the supply air blower and the exhaust air blower in accordance with the required ventilation volume calculated by the ventilation volume calculation unit;
When it is determined that the current time is within a predetermined time, the ventilation device controls the operation of the supply air blower and the exhaust air blower so that the required ventilation volume corresponds to the maximum number of people stored in the memory unit until the time when the number of people occupying the room reaches its maximum value.

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