Heat exchange ventilation system

Abstract

To provide a heat exchange ventilation system that can suppress the increase in power consumption. [Solution] The heat exchange ventilation system 1 comprises a heat exchange element 4 that exchanges heat between an air supply flow from outdoors to indoors and an exhaust flow from indoors to outdoors, an air supply fan 10 that sends the air supply flow indoors, an exhaust fan 9 that sends the exhaust flow outdoors, a filter 15 for removing dust from the air supply flow, a notification unit 50 that notifies the maintenance time for the filter 15, and a control unit 3 that controls the air supply fan 10 and the exhaust fan 9. The notification unit 50 also notifies the maintenance time for the filter 15 in stages.

Description

[[Technical Field]]

[0001] The present invention relates to a heat exchange ventilator. [[Background Art]]

[0002] Conventionally, as a device capable of ventilating without impairing cooling or heating effects, a heat exchange ventilator that performs heat exchange between a supply air flow and an exhaust air flow during ventilation is known. Also, as one type of heat exchange ventilator, a heat exchange ventilator that can be installed in a ceiling space or the like is known (e.g., Patent Document 1). [[Prior Art Documents]] [[Patent Documents]]

[0003] [[Patent Document 1]] Japanese Unexamined Patent Application Publication No. 2021-156448 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] A conventional heat exchange ventilator as disclosed in Patent Document 1 includes a filter that suppresses intrusion of dust (such as sand, dust, or insects) contained in outside air into an indoor space. When such a filter is used continuously, dust accumulates on the surface of the filter. Accumulation of dust increases pressure loss and causes an increase in power consumption. Therefore, a user needs to remove dust from the filter every certain period of time. In other words, regular maintenance is required. However, the accumulation rate of dust and the like varies depending on weather, regional characteristics, or other factors. That is, if dust accumulates faster than expected, there is a risk that the operation continues in a state where the pressure loss has increased without the user noticing, which means that there is a risk that power consumption will continuously increase.

[0005] The present invention solves the above conventional problems, and an object of the present invention is to provide a heat exchange ventilator capable of suppressing an increase in power consumption. [Means for solving the problem]

[0006] To achieve this objective, the heat exchange ventilation system according to the present invention comprises a heat exchange element that exchanges heat between an airflow from outdoors to indoors and an exhaust airflow from indoors to outdoors, an air supply fan that sends the airflow indoors, an exhaust fan that sends the exhaust airflow outdoors, a filter for removing dust from the airflow, a notification unit that notifies when the filter needs maintenance, and a control unit that controls the air supply fan and the exhaust fan. The notification unit also notifies the filter maintenance schedule in stages. This achieves the intended objective. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a heat exchange type ventilation system that can suppress an increase in power consumption. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram showing the overall configuration of a heat exchange ventilation system. [Figure 2] Figure 2 is a block diagram showing the configuration of the control unit and its surroundings in Embodiment 1. [Figure 3] Figure 3 is a flowchart showing the flow of the first maintenance notification process in Embodiment 1. [Figure 4] Figure 4 is a block diagram showing the configuration of the control unit and its surroundings in Embodiment 2. [Figure 5] Figure 5 is a flowchart showing the flow of the second maintenance notification process in Embodiment 2. [Figure 6] Figure 6 is a block diagram showing the configuration of the control unit and its surroundings in Embodiment 3. [Figure 7] Figure 7 is a flowchart showing the flow of the third maintenance notification process in Embodiment 3. [Figure 8] Figure 8 is a schematic diagram illustrating the maintenance timing estimation in Embodiment 3. [Figure 9] Figure 9 is a block diagram showing the configuration of the control unit and its surroundings in Embodiment 4. [Figure 10] Figure 10 is a flowchart showing the flow of the third maintenance notification process in Embodiment 4. [Modes for carrying out the invention]

[0009] The embodiments for carrying out the present invention will be described below with reference to the attached drawings. The embodiments described below are all preferred specific examples of the present invention. Therefore, the numerical values, shapes, materials, and components shown in the following embodiments, as well as the arrangement and connection configurations of the components, are examples only and are not intended to limit the present invention. Accordingly, among the components in the following embodiments, those not described in the independent claim representing the highest-level concept of the present invention will be described as optional components. Furthermore, in each figure, substantially identical components are denoted by the same reference numerals, and redundant explanations are omitted or simplified.

[0010] (Embodiment 1) First, the overall configuration of the heat exchange ventilation system 1 will be explained with reference to Figure 1. Figure 1 is a schematic diagram showing the overall configuration of the heat exchange ventilation system 1.

[0011] The heat exchange ventilation system 1 is a ventilation fan that exchanges indoor air with outdoor air while exchanging heat. The heat exchange ventilation system 1 can be suitably installed in the attic, underfloor space, or wall space of a building. The heat exchange ventilation system 1 comprises an air supply passage 120, an exhaust passage 110, and a heat exchange element 4 that exchanges heat between the air in the air supply passage 120 and the air in the exhaust passage 110.

[0012] The air supply passage 120 is an air passage that guides outdoor air into the building. In this embodiment, the air supply passage 120 guides outdoor air as an air supply flow into the building via the duct 13, the air supply inlet 7, the heat exchange element 4, the air supply fan 10, the air supply outlet 8, and the duct 14.

[0013] The duct 13 is a member that guides outdoor air to the heat exchange element 4 via the supply air suction port 7. That is, the duct 13 is installed upstream of the heat exchange element 4 in the supply air duct 120. The duct 13 is also provided with a filter 15.

[0014] The filter 15 is a member that adsorbs dust contained in outdoor air. That is, the filter 15 suppresses dust contained in outdoor air (supply airflow) from entering the room. The filter 15 is not limited in type as long as it allows air to pass through while adsorbing dust contained in the air. Specifically, a common coarse dust filter or a HEPA (High Efficiency Particulate Air) filter can be used as the filter 15. The filter 15 is installed in the air duct inside the duct 13. In other words, the filter 15 is provided upstream of the heat exchange element 4 in the supply air duct 120.

[0015] The supply air suction port 7 is an opening that sucks in outdoor air through the duct 13 and guides the air to the heat exchange element 4.

[0016] The heat exchange element 4 is a member that exchanges heat between the air in the supply air duct 120 and the air in the exhaust air duct 110. More specifically, the heat exchange element 4 enables heat exchange between the air flowing through the supply air duct 120 (supply airflow) and the air flowing through the exhaust air duct 110 (exhaust airflow) without mixing the two air streams. In other words, the heat exchange element 4 exchanges heat between the supply airflow going from outdoors to indoors and the exhaust airflow going from indoors to outdoors.

[0017] The supply air blower 10 is a device for feeding air in the supply air duct 120. In other words, the supply air blower 10 is a blower that generates an airflow (supply airflow) in the supply air duct 120. That is, the supply air blower 10 sends the supply airflow indoors. The supply air blower 10 is provided downstream of the heat exchange element 4 in the supply air duct 120. The supply air blower 10 comprises a supply air fan 18 and a supply air motor 19.

[0018] The air supply fan 18 is a fan for sending out air in the air supply air duct 120. The air supply fan 18 is not particularly limited in type as long as it can send out air. Specifically, for example, a sirocco fan can be used as the air supply fan 18. Further, the air supply fan 18 is attached to an air supply motor 19, and rotates as the air supply motor 19 is driven.

[0019] The air supply motor 19 is connected to the air supply fan 18. The rotation of the air supply motor 19 drives the air supply fan 18 to rotate, thereby generating an airflow in the air supply air duct 120.

[0020] The air supply outlet 8 is an opening for blowing out air in the air supply air duct 120. The air supply outlet 8 blows air into the room through the duct 14.

[0021] The duct 14 is a member that guides the air blown out from the air supply outlet 8 into the room. In other words, the duct 14 is arranged downstream of the heat exchange element 4 in the air supply air duct 120.

[0022] The exhaust air duct 110 is an air duct that guides indoor air to the outdoors. In the present embodiment, the exhaust air duct 110 guides indoor air as an exhaust airflow to the outdoors through the duct 11, the exhaust suction port 5, the heat exchange element 4, the exhaust blower 9, the exhaust outlet 6, and the duct 12.

[0023] The duct 11 is a member that guides indoor air to the heat exchange element 4 through the exhaust suction port 5. That is, the duct 11 is arranged upstream of the heat exchange element 4 in the exhaust air duct 110.

[0024] The exhaust suction port 5 is an opening that sucks indoor air through the duct 11 and guides the air to the heat exchange element 4.

[0025] The exhaust fan 9 is a device for supplying air within the exhaust air passage 110. In other words, the exhaust fan 9 is a fan that generates airflow (exhaust flow) within the exhaust air passage 110. That is, the exhaust fan 9 sends the exhaust flow to the outside. The exhaust fan 9 is also installed downstream of the heat exchange element 4 in the exhaust air passage 110. The exhaust fan 9 comprises an exhaust fan 16 and an exhaust motor 17.

[0026] The exhaust fan 16 is a fan that blows air out of the exhaust air passage 110. The exhaust fan 16 does not need to be of any particular type as long as it can blow air out. Specifically, a sirocco fan or the like can be used as the exhaust fan 16. The exhaust fan 16 is attached to the exhaust motor 17 and rotates in conjunction with the drive of the exhaust motor 17.

[0027] The exhaust motor 17 is connected to the exhaust fan 16. The exhaust motor 17 rotates itself, causing the exhaust fan 16 to rotate and generating airflow in the exhaust air passage 110.

[0028] The exhaust outlet 6 is an opening for blowing out air from the exhaust air passage 110. The exhaust outlet 6 blows air to the outside via the duct 12.

[0029] The duct 12 is a component that guides the air blown out of the exhaust outlet 6 to the outside. In other words, the duct 12 is installed downstream of the heat exchange element 4 in the exhaust air passage 110.

[0030] The heat exchange ventilation system 1 further comprises a notification unit 50 and a control unit 3.

[0031] The notification unit 50 is a device that notifies the user of the status of the heat exchange ventilation system 1 and the filter 15. More specifically, the notification unit 50 notifies the user in stages of when maintenance of the filter 15 is due. The notification unit 50 can be any medium that can convey information to the user, and is not limited to any particular type. For example, a smartphone or a personal computer can be used as the notification unit 50. In this embodiment, as an example, the notification unit 50 is a remote control for the heat exchange ventilation system 1, which is installed on the wall of the living room, etc. The notification unit 50 is equipped with an LCD screen and a speaker, and conveys information to the user using images or sounds.

[0032] The control unit 3 controls the operation of the exhaust fan 9, the supply fan 10, and the notification unit 50. More specifically, the control unit 3 is communicatively connected to the exhaust motor 17, the supply motor 19, and the notification unit 50. Based on parameters relating to the status of the supply motor 19, the control unit 3 provides step-by-step notifications regarding the maintenance timing of the filter 15.

[0033] Next, the configuration of the control unit 3 will be described with reference to Figure 2. Figure 2 is a block diagram showing the configuration of the control unit 3 and its surroundings in Embodiment 1.

[0034] The control unit 3 controls the air supply fan 10 and the exhaust fan 9. In particular, in this embodiment, the control unit 3 estimates the maintenance timing for the filter 15 based on parameters related to the state of the air supply fan 10, and notifies the user of the estimation result via the notification unit 50. Here, the "parameters related to the state of the air supply fan 10" are parameters that contribute to the power consumption of the air supply motor 19, such as the rotational speed or current value of the air supply motor 19. In this embodiment, as an example, we will describe an example where the "parameters related to the state of the air supply fan 10" is the rotational speed of the air supply motor 19. In other words, the control unit 3 estimates the maintenance timing for the filter 15 based on the rotational speed of the air supply fan 10 (air supply motor 19). The control unit 3 includes a motor state acquisition unit 31, a motor state determination unit 32, a notification unit 33, and a timing unit 34.

[0035] The motor status acquisition unit 31 acquires the rotational speed N of the air supply fan 10 (air supply motor 19). In other words, the motor status acquisition unit 31 acquires parameters related to the state of the air supply fan 10. The motor status acquisition unit 31 also outputs the acquired rotational speed N of the air supply motor 19 to the motor status determination unit 32.

[0036] The motor status determination unit 32 compares the rotational speed N of the air supply motor 19, acquired by the motor status acquisition unit 31, with a first threshold R1 and a second threshold R2, and determines whether to issue a notification. It also outputs the result of the determination to the notification unit 33.

[0037] More specifically, first, the motor state determination unit 32 determines whether the rotational speed N acquired by the motor state acquisition unit 31 is equal to or greater than the first threshold R1. Here, if the rotational speed N is equal to or greater than the first threshold R1 If this is the case, the motor state determination unit 32 determines whether the rotational speed N is equal to or greater than the second threshold R2. If the rotational speed N is equal to or greater than the second threshold R2, the motor state determination unit 32 determines that a "second notification" is necessary. On the other hand, if the rotational speed N is less than the second threshold R2, the motor state determination unit 32 determines that a "first notification" is necessary.

[0038] Here, the first threshold R1 and the second threshold R2 can be appropriately determined by the designer based on the acceptable rotational speed N of the air supply motor 19. In other words, the first threshold R1 and the second threshold R2 are determined based on the acceptable degree of clogging of the filter 15. For example, if the air supply fan 10 attempts to maintain a constant airflow regardless of the degree of clogging of the filter 15, the rotational speed of the air supply motor 19 will increase as the clogging of the filter 15 progresses. However, since the air supply motor 19 has a rated rotational speed, operating it at a speed higher than that increases the risk of failure. In other words, maintenance of the filter 15 must be performed before the air supply motor 19 reaches its rated rotational speed. Therefore, the second threshold R2 is set to a value lower than the rated rotational speed. Specifically, the second threshold R2 is set to, for example, about 90% of the rated rotational speed.

[0039] Furthermore, the first threshold R1 is set to a value smaller than the second threshold R2. Specifically, the first threshold R1 is set to, for example, about 80% of the rated rotational speed.

[0040] In other words, in this embodiment, the upper limit of the acceptable degree of clogging of the filter 15 is set to a degree of clogging such that the rotational speed N of the air supply motor 19 is 90% of the rated rotational speed. To put it another way, a state in which the rotational speed N is equal to or greater than the second threshold R2 means that maintenance of the filter 15 is required (content of the second notification). Also, a state in which the rotational speed N is equal to or greater than the first threshold R1 and less than the second threshold R2 means that maintenance of the filter 15 will be required in the near future (content of the first notification).

[0041] The first notification will include information indicating that filter 15 will soon require maintenance. Specifically, in the first notification, the notification unit 50 will broadcast a message, either visually or audibly, such as, "The maintenance period for filter 15 is approaching. We recommend maintenance within one week."

[0042] The second notification includes a statement that filter 15 currently requires maintenance. Specifically, in the second notification, the notification unit 50 broadcasts a message such as "It is time to maintain filter 15. Please perform maintenance," either as video or audio.

[0043] The notification unit 33 notifies the notification unit 50 based on the determination result of the motor status determination unit 32.

[0044] More specifically, if the motor status determination unit 32 determines that a first notification is necessary, the notification unit 33 instructs the notification unit 50 to issue the first notification.

[0045] Furthermore, if the motor status determination unit 32 determines that a second notification is necessary, the notification unit 33 instructs the notification unit 50 to issue a second notification.

[0046] The timing unit 34 manages the execution time interval of the first maintenance notification process S100, which will be described later. The timing unit 34 is a so-called timer, and once the first notification maintenance process S100 is completed, it starts counting down from a predetermined time, and when the count reaches "0", it restarts the first maintenance notification process S100. The predetermined time can be determined as appropriate by the designer. In this embodiment, the first maintenance notification process S100 is performed every 24 hours. The procedure will be executed. In other words, the predetermined time is set to "24", and for every hour that passes, the count decreases by "1", and when it reaches "0", the first maintenance notification process S100 will start again.

[0047] The above describes the configuration of the heat exchange type ventilation device 1 according to Embodiment 1.

[0048] Next, the operation of the heat exchange ventilation system 1 will be described with reference to Figures 1, 2, and 3. Figure 3 is a flowchart showing the flow of the first maintenance notification process S100 in Embodiment 1.

[0049] The first maintenance notification process S100 is performed while the heat exchange ventilation system 1 is in operation. The first maintenance notification process S100 notifies the user of the maintenance timing for the filter 15 based on the rotation speed N of the supply air motor 19 (supply air fan 10) as a parameter related to the state of the supply air fan 10. In other words, the notification unit 50 issues a first notification when the rotation speed N of the supply air motor 19 increases due to clogging of the filter 15, and when the rotation speed N exceeds the first threshold R1, it issues a second notification when it exceeds the second threshold R2. In other words, the notification unit 50 notifies the user of the maintenance timing for the filter 15 in stages. That is, the first maintenance notification process S100 makes it easier for the user to understand the state of the filter 15. This makes it possible to perform maintenance at the appropriate time and suppress the increase in power consumption associated with clogging of the filter 15.

[0050] When the first maintenance notification process S100 is started, the motor status acquisition unit 31 acquires the rotational speed N of the air supply motor 19 of the air supply fan 10 (S101). For example, the motor status acquisition unit 31 acquires that the rotational speed N of the air supply motor 19 at this point is 1900 rpm.

[0051] Next, the motor state determination unit 32 determines whether the rotational speed N acquired by the motor state acquisition unit 31 is equal to or greater than the first threshold R1 (S102). Here, as an example, let's assume that the first threshold R1 is 1800 rpm. In other words, in this example, the rotational speed N is equal to or greater than the first threshold R1 (YES in S102).

[0052] Next, the motor state determination unit 32 determines whether the rotational speed N acquired by the motor state acquisition unit 31 is equal to or greater than the second threshold R2, if the rotational speed N is equal to or greater than the first threshold R1 (S103). Here, as an example, let's assume that the second threshold R2 is 2000 rpm, which is a value greater than the first threshold R1. In other words, in this example, the rotational speed N is not equal to or greater than the second threshold R2. To put it another way, the rotational speed N is less than the second threshold R2 (NO in S103).

[0053] If the rotational speed N is less than the second threshold R2, the notification unit 33 instructs the notification unit 50 to issue a first notification (S104). In other words, the notification unit 50 issues a first notification.

[0054] As mentioned above, the first notification is an announcement that maintenance for filter 15 is due soon.

[0055] Next, the timing unit 34 starts measuring a predetermined time and waits until the predetermined time has elapsed (S106). Here, the predetermined time is the time interval at which the first maintenance notification process S100 is executed. The predetermined time can be appropriately determined by the designer, taking into consideration the installation environment of the heat exchange ventilation device 1, etc. In this embodiment, as an example, the predetermined time is set to 24 hours.

[0056] Next, after a predetermined time has elapsed, the motor status acquisition unit 31 acquires the rotation speed of the air supply motor 19 of the air supply fan 10 again (S101). In this manner, the first maintenance notification process S100 is repeated at predetermined intervals.

[0057] Here, we will explain the case where the rotational speed N acquired by the motor state acquisition unit 31 in S101 was 1700 rpm. In other words, we will explain the case where the rotational speed N was less than the first threshold R1 (1800 rpm) (NO in S102).

[0058] In this case, the notification unit 33 does not notify the notification unit 50, and after a predetermined time has elapsed (S106), the motor status acquisition unit 31 again acquires the rotation speed N of the air supply motor 19 of the air supply fan 10 (S101).

[0059] Next, we will explain the case where the rotational speed N acquired by the motor state acquisition unit 31 in S101 was 2100 rpm. In other words, we will explain the case where the rotational speed N was greater than or equal to the second threshold R2 (2000 rpm) (YES in S103).

[0060] In this case, the notification unit 33 instructs the notification unit 50 to issue a second notification (S105). In other words, the notification unit 50 issues a second notification.

[0061] The second notification, as mentioned above, is an announcement that filter 15 requires maintenance.

[0062] This configuration allows the degree of clogging of the filter 15 to be notified in stages through the first and second notifications, enabling the user to check for signs of clogging early. This allows the user to perform maintenance at the appropriate time. As a result, the heat exchange ventilation system 1 is less likely to continue operating with high pressure loss, thus suppressing an increase in power consumption.

[0063] The above describes Embodiment 1. (Embodiment 2) Embodiment 1 described an example in which either the first or second notification is given. On the other hand, Embodiment 2 describes an example in which a third notification is given in addition to the first and second notifications in order to give a notification that takes into account the time change in the clogging of the filter 15.

[0064] First, the control unit 3 in Embodiment 2 will be described with reference to Figure 4. Figure 4 is a block diagram showing the configuration of the control unit 3 and its surroundings in Embodiment 2. In the following description, components that are substantially the same as those in Embodiment 1 will be given the same reference numerals, and their descriptions will be simplified or omitted.

[0065] As shown in Figure 4, the control unit 3 in Embodiment 2 further comprises a storage unit 35.

[0066] The memory unit 35 is responsible for storing and deleting the history of when the first notification was issued. In other words, the memory unit 35 is a so-called memory. When the first notification is issued, the memory unit 35 stores that the execution history of the first notification "exists". The memory unit 35 also deletes the execution history of the first notification when the user performs maintenance on the filter 15. In other words, it stores that the execution history of the first notification "does not exist". The deletion of the execution history is performed, for example, by input from the remote control. The memory unit 35 also deletes the execution history of the first notification when the third notification, which will be described later, is issued.

[0067] Furthermore, in Embodiment 2, the motor state determination unit 32 determines whether there is a history of issuing a first notification if the rotational speed N (parameter) of the air supply motor 19 is equal to or greater than the second threshold R2. If there is a history of issuing a first notification, the motor state determination unit 32 determines that a second notification is necessary. On the other hand, if there is no history of issuing a first notification, the motor state determination unit 32 determines... Therefore, it is determined that a third notification is necessary.

[0068] The third notification informs the user that the filter 15 is rapidly becoming clogged and therefore requires immediate action (maintenance). The third notification may also include information such as the high risk of failure of the air supply motor 19, the reduced ventilation airflow due to the clogging of the filter 15, or the risk of damage to the filter 15 due to increased pressure. In short, the third notification is more strongly urging maintenance than the second notification.

[0069] Next, the second maintenance notification process S200 will be described with reference to Figures 1, 4, and 5. Figure 5 is a flowchart showing the flow of the second maintenance notification process S200 in Embodiment 2.

[0070] The second maintenance notification process S200 is performed while the heat exchange ventilation system 1 is in operation. The second maintenance notification process S200 issues a third notification prompting immediate maintenance if the filter 15 is clogging rapidly. In other words, the second maintenance notification process S200 makes it easier for the user to understand the condition of the filter 15, taking into account the clogging rate. This allows maintenance to be performed at a more appropriate time, suppressing the increase in power consumption associated with the clogging of the filter 15. It also helps to prevent insufficient ventilation volume or failure of the filter 15 or the air supply motor 19 caused by excessive clogging of the filter 15.

[0071] When the second maintenance notification process S200 is started, the motor status acquisition unit 31 acquires the rotational speed N of the air supply motor 19 of the air supply fan 10 as a parameter related to the status of the air supply fan 10 (S201). For example, the motor status acquisition unit 31 acquires that the rotational speed N of the air supply motor 19 of the air supply fan 10 at this point is 1900 rpm. Next, the motor status determination unit 32 determines whether the rotational speed acquired by the motor status acquisition unit 31 is equal to or greater than the first threshold R1 (S202). In this embodiment, the first threshold R1 is assumed to be 1800 rpm. In other words, in this example, the rotational speed N is equal to or greater than the first threshold R1 (YES in S202).

[0072] Next, the motor state determination unit 32 determines whether the rotational speed N acquired by the motor state acquisition unit 31 is greater than or equal to the second threshold R2 (S203). In this embodiment, as an example, the second threshold R2 is assumed to be 2000 rpm, which is a value greater than the first threshold R1. In other words, in this example, the rotational speed N is not greater than or equal to the second threshold R2. To put it another way, the rotational speed N is less than the second threshold R2 (NO in S203).

[0073] If the rotational speed N is less than the second threshold R2, the notification unit 33 instructs the notification unit 50 to issue a first notification (S206). In other words, the notification unit 50 issues a first notification.

[0074] Next, the memory unit 35 stores the first notification history (S207). In other words, the memory unit 35 stores that there is a history of the first notification.

[0075] Next, the unit waits until a predetermined time has elapsed (S210). After the predetermined time has elapsed, the motor status acquisition unit 31 again acquires the rotation speed N of the air supply motor 19 of the air supply fan 10 (S201).

[0076] Here, we will explain the case where the rotational speed N acquired by the motor state acquisition unit 31 is 2100 rpm. In other words, assume that the rotational speed N is greater than or equal to the second threshold R2 (2000 rpm) (YES in S203). In this case, the motor state determination unit 32 refers to the storage unit 35 and determines whether the first notification history is stored (S204). In other words, the motor The state determination unit 32 determines whether the memory unit 35 has stored a record of the first notification. Here, let's assume that the memory unit 35 did not have a record of the first notification (NO in S204). In other words, let's assume that it has stored a record of the first notification "not present".

[0077] In this case, the notification unit 33 instructs the notification unit 50 to issue a third notification (S208). In other words, the notification unit 50 issues a third notification.

[0078] As mentioned above, the third notification is a message informing the user that filter 15 is rapidly becoming clogged and that immediate action (maintenance) is required.

[0079] Next, the memory unit 35 deletes the first notification history (S209), and after a predetermined time has elapsed (S210), the motor status acquisition unit 31 again acquires the rotation speed N of the air supply motor 19 of the air supply fan 10 (S201).

[0080] Here, we will explain the case where there was a record of the first notification (YES in S204). In other words, let's assume that the memory unit 35 has a record of the first notification (YES in S204).

[0081] In this case, the notification unit 33 instructs the notification unit 50 to issue a second notification (S205). In other words, the notification unit 50 issues a second notification.

[0082] This configuration makes it possible to notify the user of the rapid clogging of filter 15, thereby increasing the user's awareness of maintenance. Furthermore, by also informing the user about the risk of component failure, the user's awareness of maintenance can be further increased. As a result, the increase in power consumption associated with the clogging of filter 15 can be suppressed. (Embodiment 3) Embodiment 1 describes an example in which either a first or second notification is given to inform the user that the filter 15 is becoming clogged. On the other hand, Embodiment 3 describes an example in which the system estimates and notifies the user of the timing of maintenance, regardless of whether maintenance of the filter 15 is actually required at that time, so that the user can always be aware of when maintenance is needed.

[0083] First, the control unit 3 in Embodiment 3 will be described with reference to Figure 6. Figure 6 is a block diagram showing the configuration of the control unit 3 and its surroundings in Embodiment 3. In the following description, components that are substantially the same as those in Embodiments 1 and 2 will be given the same reference numerals, and their descriptions will be simplified or omitted.

[0084] As shown in Figure 6, the control unit 3 in Embodiment 3 further includes a maintenance timing estimation unit 36.

[0085] The maintenance timing estimation unit 36 ​​estimates when maintenance will be required based on the time change in the rotational speed N of the air supply motor 19 (a parameter related to the state of the air supply fan 10). More specifically, the maintenance timing estimation unit 36 ​​calculates an approximate straight line from multiple values ​​(rotational speed N) measured by the motor state acquisition unit 31 and estimates the maintenance timing of the filter 15. The maintenance timing estimation process by the control unit 3 will be described in detail later.

[0086] Furthermore, the storage unit 35 in this embodiment stores the rotational speed N of the air supply motor 19. More specifically, the rotational speed N of the air supply motor 19 is stored each time the third maintenance notification process S300 is executed. In other words, the third maintenance notification process S300 stores information that allows for the estimation of the time change in the rotational speed N of the air supply motor 19.

[0087] Next, the third maintenance notification process S300 will be described with reference to Figures 1, 6, 7, and 8. Figure 7 is a flowchart showing the flow of the third maintenance notification process S300 in Embodiment 3. Figure 8 is a schematic diagram showing an image of maintenance timing estimation in Embodiment 3.

[0088] The third maintenance notification process S300 is performed while the heat exchange ventilation system 1 is in operation. The third maintenance notification process S300 estimates the maintenance timing for the filter 15 based on the change in rotational speed of the supply motor 19 of the supply air blower 10 and notifies the user of that timing. In other words, the third maintenance notification process S300 allows the user to always be aware of the clogging status of the filter 15. This makes it possible to perform preventive maintenance on the filter 15 and suppress the increase in power consumption associated with the clogging of the filter 15.

[0089] The third maintenance notification process S300 is executed repeatedly, but first, we will explain the initial third maintenance notification process S300.

[0090] When the third maintenance notification process S300 is started, the motor status acquisition unit 31 acquires the rotational speed N of the air supply motor 19 as a parameter related to the status of the air supply fan 10, and stores this value in the storage unit 35 (S301). For example, the motor status acquisition unit 31 acquires that the rotational speed N of the air supply motor 19 at this point is 1300 rpm, and stores this value of rotational speed N in the storage unit 35. At this time, the storage unit 35 has stored (plotted) only one value of rotational speed N, as shown in Figure 8(a).

[0091] Next, the maintenance timing estimation unit 36 ​​determines whether multiple rotation speed N values ​​for the air supply motor 19 are stored in the storage unit 35 (S302). Currently, only one rotation speed N is stored in the storage unit 35 (NO in S302), so it waits until a predetermined time has elapsed (S306). In this embodiment, as an example, the predetermined time is set to 24 hours. After the predetermined time has elapsed, the process returns to S301. In other words, the second third maintenance notification process S300 begins. By repeating the third maintenance notification process S300 in this way, multiple rotation speed N values ​​are stored in the storage unit 35.

[0092] Next, as an example, we will explain the third maintenance notification process S300.

[0093] When the third maintenance notification process S300 is initiated, the motor status acquisition unit 31 acquires the rotational speed N of the air supply motor 19 and stores that value in the storage unit 35 (S301). For example, the motor status acquisition unit 31 acquires that the rotational speed N of the air supply motor 19 at this point is 1330 rpm and stores that value of rotational speed N in the storage unit 35. Let's assume that the rotational speed of the air supply motor 19 was stored as 1320 rpm during the second maintenance notification process S300. In other words, at this point, the storage unit 35 has stored (plotted) three rotational speeds N, as shown in Figure 8(b).

[0094] Next, it is determined whether multiple rotation speeds of the air supply motor 19 are stored in the memory unit 35 (S302). In this example, three (multiple) rotation speeds of the air supply motor 19 are stored (YES in S302).

[0095] Next, the maintenance timing estimation unit 36 ​​calculates an approximate straight line L from the rotational speed N of the air supply motor 19 stored in the memory unit 35 (S303). That is, from the state in Figure 8(b), an approximate straight line L as shown in Figure 8(c) is calculated. Note that the method for calculating the approximate straight line L is not particularly limited. For example, the least squares method can be used to calculate the approximate straight line L.

[0096] Next, the time at which the rotational speed N of the air supply motor 19 exceeds a predetermined rotational speed Nm (the upper limit of the parameters related to the state of the air supply fan 10), which is a rotational speed that serves as a guideline for maintenance, is estimated from the calculated approximate straight line L (S304). In this embodiment, as an example, the predetermined rotational speed Nm is set to 1800 rpm. For example, as shown in Figure 8(c), the maintenance timing estimation unit 36 ​​determines the estimated time T at which maintenance is required from the intersection of the approximate straight line L and the predetermined rotational speed Nm.

[0097] Next, the maintenance timing estimation unit 36 ​​can determine the time until maintenance is required (remaining operating time Ta) by taking the difference between the estimated time T and the operating time at this point (48 hours in this example). Here, let's assume that the estimated time T is 300 hours as an example. Also, the operating time at this point is 48 hours. In other words, the time until maintenance is required (remaining operating time Ta) is the difference between these times (300 hours - 48 hours), which is 252 hours. To put it another way, the maintenance timing estimation unit 36 ​​estimates the remaining operating time Ta until the rotational speed N of the air supply motor 19 (a parameter related to the state of the air supply fan 10) exceeds a predetermined rotational speed Nm (upper limit) based on the approximate straight line L.

[0098] Next, the notification unit 33 instructs the notification unit 50 to notify the remaining operating time Ta estimated in S304. In other words, the notification unit 50 notifies the remaining operating time Ta.

[0099] As described above, the remaining operating time Ta is updated each time the third maintenance notification process S300 is executed. In other words, the notification unit 50 notifies the remaining operating time Ta each time the control unit 3 estimates it. To put it another way, the notification unit 50 notifies the maintenance timing of the filter 15 in stages.

[0100] This configuration allows users to proactively perform maintenance on the filter 15. Therefore, it is possible to prevent the heat exchange ventilation system 1 from continuing to operate with increased pressure loss. As a result, an increase in power consumption can be suppressed.

[0101] In other words, the notification unit 50 updates the remaining operating time Ta each time the third notification maintenance process S300 is executed, thereby providing step-by-step notifications about when the filter 15 needs maintenance. This prevents the heat exchange ventilation system 1 from continuing to operate with high pressure loss and suppresses an increase in power consumption.

[0102] In other words, users can always check the maintenance schedule and plan maintenance to fit their own schedule. This means that if their busy season coincides with the maintenance schedule for filter 15, they can bring the maintenance forward. As a result, it is possible to prevent the heat exchange ventilation system 1 from operating with increased pressure loss, thereby suppressing an increase in power consumption. (Embodiment 4) Embodiment 3 described an example in which the maintenance timing (remaining operating time Ta) of the filter 15 is always estimated and notified. On the other hand, Embodiment 4 describes an example in which a message prompting maintenance is notified when the remaining operating time Ta falls below a predetermined value, in order to make it easier for the user to grasp when to perform maintenance.

[0103] First, the control unit 3 in Embodiment 4 will be described with reference to Figure 9. Figure 9 is a block diagram showing the configuration of the control unit 3 and its surroundings in Embodiment 4. In the following description, components that are substantially the same as those in Embodiment 3 will be given the same reference numerals, and their descriptions will be simplified or omitted.

[0104] As shown in Figure 9, the control unit 3 in Embodiment 4 further includes the notification necessity determination unit 37 Prepare.

[0105] The notification necessity determination unit 37 compares the maintenance timing (remaining operating time Ta) of the filter 15 estimated by the maintenance timing estimation unit 36 ​​with a predetermined value Ts and determines whether to issue a maintenance notification. More specifically, the notification necessity determination unit 37 determines whether the remaining operating time Ta is less than or equal to the predetermined value Ts. If the determination shows that the remaining operating time Ta is less than or equal to the predetermined value Ts, the remaining operating time Ta and a message prompting maintenance are notified via the notification unit 33 and the notification unit 50. On the other hand, if the remaining operating time Ta is not less than or equal to the predetermined value Ts, only the remaining operating time Ta is notified via the notification unit 33 and the notification unit 50.

[0106] The predetermined value Ts can be determined by the designer as appropriate. Specifically, the predetermined value Ts can be set to, for example, 168 hours (one week) to 336 hours (two weeks).

[0107] Next, the fourth maintenance notification process S400 will be described with reference to Figures 1, 8, 9, and 10. Figure 10 is a flowchart showing the flow of the fourth maintenance notification process S400 in Embodiment 4.

[0108] The fourth maintenance notification process S400 is executed repeatedly, but first, we will explain the initial fourth maintenance notification process S400.

[0109] When the fourth maintenance notification process S400 is started, the motor status acquisition unit 31 acquires the rotational speed N of the air supply motor 19 as a parameter related to the status of the air supply fan 10, and stores this value in the storage unit 35 (S401). For example, the motor status acquisition unit 31 acquires that the rotational speed of the air supply motor 19 at this point is 1300 rpm, and stores the value of this rotational speed N in the storage unit 35. At this time, the storage unit 35 has stored (plotted) only one rotational speed value, as shown in Figure 8(a).

[0110] Next, it is determined whether multiple rotation speeds N of the air supply motor 19 are stored in the memory unit 35 (S402). Currently, only one rotation speed N is stored in the memory unit 35 (NO in S402), so it waits until a predetermined time has elapsed (S408). In this embodiment, as an example, the predetermined time is set to 24 hours. After the predetermined time has elapsed, the process returns to S401. In other words, the second fourth maintenance notification process S400 begins. By repeating the fourth maintenance notification process S400 in this way, the memory unit 35 stores multiple rotation speeds N.

[0111] Next, as an example, we will explain the third fourth maintenance notification process S400.

[0112] When the third fourth maintenance notification process S400 is initiated, the motor status acquisition unit 31 acquires the rotational speed N of the air supply motor 19 and stores that value in the storage unit 35 (S401). For example, the motor status acquisition unit 31 acquires that the rotational speed N of the air supply motor 19 at this point is 1330 rpm and stores that value of rotational speed N in the storage unit 35. Let's assume that the rotational speed N of the air supply motor 19 was stored as 1320 rpm in the second fourth maintenance notification process S400. At this time, the storage unit 35 has stored (plotted) three rotational speeds N, as shown in Figure 8(b).

[0113] Next, the maintenance timing estimation unit 36 ​​determines whether multiple rotation speeds N of the air supply motor 19 are stored in the memory unit 35 (S402). In this example, three (multiple) rotation speeds N of the air supply motor 19 are stored, so the branch in S402 is YES, and the process proceeds to S403.

[0114] Next, the maintenance timing estimation unit 36 ​​calculates an approximate straight line L from the rotational speed N of the air supply motor 19 stored in the memory unit 35 (S403). That is, from the state in Figure 8(b), the state in Figure 8( Calculate the approximate straight line L shown in c).

[0115] Next, the maintenance timing estimation unit 36 ​​estimates the time until the rotational speed N of the air supply motor 19 exceeds a predetermined rotational speed Nm, which is a guideline for maintenance, from the calculated approximate straight line L (S404). In this embodiment, as an example, the predetermined rotational speed Nm is set to 1800 rpm. For example, as shown in Figure 8(c), the maintenance timing estimation unit 36 ​​can determine the estimated time T when maintenance is required from the intersection of the approximate straight line L and the predetermined rotational speed Nm.

[0116] Next, the maintenance timing estimation unit 36 ​​can determine the time until maintenance is required (remaining operating time Ta) by taking the difference between the estimated time T and the operating time at this point (48 hours in this example). Here, let's assume that the estimated time T is 300 hours as an example. Also, the operating time at this point is 48 hours. In other words, the time until maintenance is required (remaining operating time Ta) is the difference between these times (300 hours - 48 hours), which is 252 hours.

[0117] Next, the notification necessity determination unit 37 determines whether the time until the rotational speed N of the air supply motor 19 exceeds a predetermined rotational speed Nm (remaining operating time Ta), calculated by the maintenance timing estimation unit 36, is less than or equal to a predetermined value Ts (S405). Here, the predetermined value Ts is set to "336 hours (two weeks)". In other words, the remaining operating time Ta (252 hours) is less than or equal to the predetermined value Ts (336 hours) (YES in S405).

[0118] Next, the notification unit 33 instructs the notification unit 50 to notify the remaining operating time Ta and a message prompting maintenance of the filter 15. In other words, the notification unit 50 notifies the remaining operating time Ta and a message prompting maintenance of the filter 15.

[0119] Next, we will explain the case where the predetermined value Ts is "168 hours". In other words, we will explain the case where the remaining operating time Ta is not less than or equal to the predetermined value Ts.

[0120] In S405, if the remaining operating time Ta (252 hours) is not less than or equal to the predetermined value Ts (168 hours) (NO in S405), the notification necessity determination unit 37 will notify only the remaining operating time Ta via the notification unit 33 and the notification unit 50 (S407). In other words, the notification unit 50 will notify the remaining operating time Ta, but will not notify a message prompting maintenance.

[0121] Next, after waiting for a predetermined time (S408), the fourth maintenance notification process S400 is executed again.

[0122] As described above, the notification unit 50 notifies the remaining operating time Ta if it is not less than or equal to a predetermined value Ts, and notifies the remaining operating time Ta and a message prompting maintenance of the filter 15 if it is less than or equal to a predetermined value Ts.

[0123] This configuration makes it easier for users to determine when to perform maintenance, even when the remaining operating time Ta is constantly being reported, allowing them to perform maintenance on the filter 15 at the appropriate time. In other words, it prevents the heat exchange ventilation system 1 from operating under conditions of high pressure loss, thereby suppressing an increase in power consumption.

[0124] The embodiments described so far are illustrative, and it will be understood by those skilled in the art that various modifications are possible for each component or combination of each processing process, and that such modifications are also within the scope of this disclosure. Modifications of the configurations shown in the embodiments will now be described. (modified version) In Embodiment 1, an example was shown in which the notification unit 50 notifies the maintenance timing of the filter 15 in stages based on the rotational speed of the air supply motor 19, but the invention is not limited to this. As also mentioned in Embodiment 1, the notification unit 50 can notify the maintenance timing of the filter 15 in stages based on parameters that contribute to the power consumption of the air supply motor 19.

[0125] For example, when the notification unit 50 provides notification based on the current value of the air supply motor 19, the control unit 3 obtains the current value I of the air supply motor 19 and then determines whether the current value I is equal to or greater than a first threshold I1. If the current value I is equal to or greater than the first threshold I1, the control unit 3 determines whether the current value I is equal to or greater than a second threshold I2. If the current value I is equal to or greater than the second threshold I2, the notification unit 50 provides a second notification. On the other hand, if the current value I is not equal to or greater than the second threshold I2, the first notification is provided. In other words, the same effect can be obtained by replacing the rotational speed with the current value in the process described in Embodiment 1. In addition, the same effect can be obtained in Embodiments 2 to 4 by similarly replacing the rotational speed with the current value in the processing.

[0126] Here, the first threshold I1 and the second threshold I2 can be appropriately determined by the designer based on the acceptable current value I of the air supply motor 19. In other words, the first threshold I1 and the second threshold I2 are determined based on the acceptable degree of clogging of the filter 15. For example, if the air supply fan 10 attempts to maintain a constant airflow regardless of the degree of clogging of the filter 15, the current value I of the air supply motor 19 will increase as the clogging of the filter 15 progresses. However, since the air supply motor 19 has a rated current value, operating it at a current value higher than that increases the risk of failure. In other words, maintenance of the filter 15 must be performed before the air supply motor 19 reaches its rated current value. Therefore, the second threshold I2 is set to a value lower than the rated current value. Specifically, the second threshold I2 is set to, for example, about 90% of the rated current value.

[0127] Furthermore, the first threshold I1 is set to a value smaller than the second threshold I2. Specifically, the first threshold I1 is set to, for example, about 80% of the rated current value. In other words, the second threshold I2 is set to a value larger than the first threshold I1.

[0128] In Embodiment 3, an example was shown in which the maintenance timing estimation unit 36 ​​calculates the approximate straight line L based on all the rotational speeds N stored in the storage unit 35, but the system is not limited to this. The maintenance timing estimation unit 36 ​​may calculate the approximate straight line L using only the relatively recent rotational speeds N among the rotational speeds N stored in the storage unit 35. Specifically, for example, when calculating the approximate straight line L in the 10th third maintenance notification process S300, the approximate straight line L may be calculated based on the rotational speeds N stored in the 8th, 9th, and 10th third maintenance notification processes S300.

[0129] With this configuration, the remaining operating time Ta can be accurately estimated even when the change in rotational speed N over time is not linear. More specifically, for example, even when the change in rotational speed N over time exhibits a quadratic function-like change, the remaining operating time Ta can be accurately estimated using linear approximation (approximation line L).

[0130] In Embodiment 4, as shown in Figure 10, an example is shown in which only the remaining operating time Ta is notified at the NO branch in S405 (S407), but the system is not limited to this. In other words, an example is shown in which only the remaining operating time Ta is notified when the remaining operating time Ta is not less than or equal to a predetermined value Ts, but the system is not limited to this. The notification necessity determination unit 37 may be configured not to notify the remaining operating time Ta and a message prompting maintenance when the remaining operating time Ta is not less than or equal to a predetermined value Ts. In other words, the notification necessity determination unit 37 may be configured not to notify the notification unit 33 and the notification unit 50 when the remaining operating time Ta is not less than or equal to a predetermined value Ts. [Industrial applicability]

[0131] This invention can be used in ventilation systems for ventilating buildings. [Explanation of Symbols]

[0132] 1. Heat exchange ventilation system 3. Control Unit 4 Heat exchange element 5. Exhaust and intake ports 6. Exhaust outlet 7. Air intake port 8 Air supply outlet 9. Exhaust fan 10. Air supply fan 11, 12, 13, 14 Ducts 15 filters 16 Exhaust fan 17 Exhaust motor 18. Intake fan 19. Air intake motor 31 Motor status acquisition unit 32 Motor status determination unit 33 Notification Department 34 Timing section 35 Storage section 36 Maintenance Schedule Estimation Unit 37 Notification necessity determination unit 50 Hochi Department 110 Exhaust air passage 120 Air intake duct

Claims

1. A heat exchange element that exchanges heat between an intake airflow from outdoors to indoors and an exhaust airflow from indoors to outdoors, A supply air blower that sends the aforementioned supply airflow into the building, An exhaust fan that sends the exhaust flow to the outdoors, A filter for removing dust from the aforementioned air supply flow, A notification unit that notifies the maintenance time for the aforementioned filter, A control unit that controls the air supply fan and the exhaust fan, Equipped with, The notification unit will notify the maintenance timing of the filter in stages. The control unit, The parameters related to the state of the aforementioned air supply fan are obtained, Determine whether the aforementioned parameter is above the first threshold, Determine whether the parameter is greater than or equal to a second threshold, which is greater than the first threshold. The aforementioned notification department, If the parameter is greater than or equal to the first threshold and less than the second threshold, the first notification is made. If the parameter is equal to or greater than the second threshold, a second notification is given. The control unit, If the parameter is equal to or greater than the second threshold, Determine if there is a history of having made the aforementioned first notification. The aforementioned notification department, If there is a history of the aforementioned first notification being made, a second notification will be made. If there is no record of the aforementioned first notification being made, a third notification will be made. Heat exchange ventilation system.

2. The control unit estimates the maintenance timing for the filter, The notification unit notifies the estimated maintenance time. The heat exchange ventilation device according to claim 1.

3. The control unit estimates the maintenance timing based on the time change of parameters related to the state of the air supply fan. The heat exchange type ventilation device according to claim 2.

4. The control unit, At predetermined intervals, parameters related to the state of the air supply fan are stored. If multiple parameters are stored, the remaining operating time until the parameter exceeds its upper limit is estimated based on the changes in the parameter. The aforementioned notification department, Each time the remaining operating time is estimated, the remaining operating time is announced. The heat exchange type ventilation device according to claim 2.

5. The aforementioned notification department, If the remaining operating time is not less than or equal to a predetermined value, the remaining operating time will be announced. If the remaining operating time is less than or equal to a predetermined value, the system will notify the remaining operating time and provide a message prompting maintenance of the filter. The heat exchange type ventilation device according to claim 4.

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