Ventilation control device

Provided is a ventilation control device (2) configured to control operation of one or more ventilators communicably connected thereto, the ventilation control device including: a target total exhaust volume storage unit (14) configured to store a target total exhaust volume that is a target total volume of exhaust to be discharged within a predetermined time; an exhaust capacity storage unit (13) configured to store the exhaust capacity of each of the one or more ventilators connected to the ventilation control device (2); an exhaust volume acquisition unit (17) configured to acquire an already-discharged exhaust volume discharged from each of the one or more ventilators connected to the ventilation control device (2); an integrating unit (18) configured to calculate a total already-discharged exhaust volume by adding up the already-discharged exhaust volumes of the one or more ventilators acquired by the exhaust volume acquisition unit; and an exhaust volume control unit (11) configured to, based on the total already-discharged exhaust volume calculated by the integrating unit (18), the target total exhaust volume stored in the target total exhaust volume storage unit (14), a remaining time until the elapse of the predetermined time, and the exhaust capacity of each of the one or more ventilators stored in the exhaust capacity storage unit (13), control each of the one or more ventilators connected to the ventilation control device (2) to achieve exhaust in the target total exhaust volume within the remaining time.

TECHNICAL FIELD

The present disclosure relates to a ventilation control device.

BACKGROUND ART

A conventional around-the-clock ventilation system according to the prior art includes a ventilator configured to ventilate at least a part of a building, and a controller configured to control the operation of the ventilator. In this around-the-clock ventilation system, the ventilator performs a ventilation operation, regardless of whether or not at least a part of the building is made use of (for example, see Patent Literature 1).

CITATION LIST

Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2002-39578

SUMMARY OF INVENTION

However, the above-mentioned around-the-clock ventilation system provides energy-saving ventilation realizable only when any person is absent in a room, and therefore, energy-saving effects in the presence of a person in a room cannot be expected from the system. Moreover, the ventilation system is required to have a mechanism, such as a sensor, for detecting the absence of a person, and, in the intermittent operation control of the ventilator including the sensor, a detection state sometimes continues for a long time. In this case, the operation time of the ventilation system is rather too long, and accordingly it is difficult to achieve energy saving effects.

The present disclosure is conceived to solve the above-described problems, and an object of the present disclosure is to provide a ventilation control device capable of, while performing sufficient around-the-clock ventilation, easily providing energy-saving ventilation, regardless of whether a person is present or absent.

To solve the above-described problems, the ventilation control device according to the present disclosure is configured to control the operation of one or more ventilators communicably connected to the ventilation control device, the ventilation control device including: a target total exhaust volume storage unit configured to store a target total exhaust volume that is a target total volume of exhaust to be discharged within a predetermined time; an exhaust capacity storage unit configured to store an exhaust capacity of each of the one or more ventilators connected to the ventilation control device; an exhaust volume acquisition unit configured to acquire an already-discharged exhaust volume discharged from each of the one or more ventilators connected to the ventilation control device; an integrating unit configured to calculate a total already-discharged exhaust volume by adding up the already-discharged exhaust volumes of the one or more ventilators acquired by the exhaust volume acquisition unit; and an exhaust volume control unit configured to, based on the total already-discharged exhaust volume calculated by the integrating unit, the target total exhaust volume stored in the target total exhaust volume storage unit, a remaining time until the elapse of the predetermined time, and the exhaust capacity of each of the one or more ventilators, the capacity being stored in the exhaust capacity storage unit, control each of the one or more ventilators connected to the ventilation control device to achieve exhaust in the target total exhaust volume within the remaining time. Thus, the expected object is achieved.

According to the present disclosure, a minimum total volume of exhaust required to be discharged within the remaining time is calculated from the target total exhaust volume and the total already-discharged exhaust volume, and a ventilation fan is operated based on the minimum total exhaust volume, whereby the volume of ventilation for the entirety of a house can be minimized to a proper level, and thus, energy-saving effects can be achieved.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that any of the embodiments described below represents a specific preferred example of the present disclosure. Therefore, numerical values, shapes, materials, constituents, arrangement positions and connection of the constituents, and steps and the order of the steps, each being described in the following embodiments, are merely exemplary and are not intended to limit the present disclosure. Hence, of the constituents in the following embodiments, constituents not set forth in independent claims which represent the most superordinate concept of the present disclosure are to be construed as optional constituents. Furthermore, in the drawings, substantially identical constituents are assigned the same reference signs, and overlapped descriptions thereof are omitted or simplified.

Embodiments

First, the outline of a ventilation system according to the present disclosure will be described with reference toFIG. 1andFIG. 2. Note thatFIG. 1is a schematic diagram of connection of an in-home network according to the present embodiment.FIG. 2is a schematic top view of an in-home space provided with a ventilation control device according to the present embodiment.

The ventilation system according to the present embodiment includes ventilation control device2, exhausters3, such as ceiling-embedded ventilation fan4, wall-mounted ventilation fan6, and range hood fan5, configured to discharge air in a house to the outside, and air supply device7configured to introduce the outside air into the house.

Ventilation control device2is installed in ordinary house1, and communicably connected to ceiling-embedded ventilation fan4, wall-mounted ventilation fan6, range hood fan5, and air supply device7, via in-home network38. Ventilation control device2is communicably connected to an external server via an external network. Ventilation control device2is communicably connected to, for example, a plurality of ventilators70provided in the house and the external server, and the connection may be wired or wireless.

Examples of exhauster3include the above-mentioned ceiling-embedded ventilation fan4, wall-mounted ventilation fan6, range hood fan5, and a heat exchange ventilation fan (not illustrated). In other words, exhauster3is a device having an exhaust function of carrying out exhaust from the inside to the outside of ordinary house1.

Examples of air supply device7include an air supply function of a heat exchange ventilation fan and an air supply fan. In other words, air supply device7is a device having an air supply function of supplying air from the outside to the inside of ordinary house1. Note that air supply device7does not necessarily have a fan, and is only required to include, for example, an air duct communicating with the inside and outside of the house, and an opening-and-closing section for opening and closing the air duct, and to be capable of electrically opening and closing the opening-and-closing section.

Examples of ventilator70include exhauster3and air supply device7. In other words, ventilator70is a device having at least any one of an air supply function and an exhaust function.

Information input terminal8is communicably connected to ventilation control device2via in-home network38or an external network. Information input terminal8is configured to cause ventilation control device2to store information necessary for constituting the ventilation system of the present embodiment. Examples of information input terminal8include devices, such as a mobile phone, a smartphone, and a tablet.

Next, functional units that constitute ventilation control device2, ceiling-embedded ventilation fan4, wall-mounted ventilation fan6, range hood fan5, and air supply device7will be described with reference toFIG. 3,FIG. 4, andFIG. 5. Note thatFIG. 3is a schematic functional block diagram of the ventilation control device and the ventilators according to the present embodiment.FIG. 4is a configuration diagram of the ventilation control device according to the present embodiment.FIG. 5is a graph illustrating an operation example of the ventilators controlled by the ventilation control device according to the present embodiment.

As illustrated inFIG. 3, ventilation control device2includes communication unit9, storage unit10, and exhaust volume control unit11.

Communication unit9includes: receiving unit for broadband12communicably connected to information input terminal8and an external server; receiving unit for ventilation15configured to receive a radio signal from each of ventilators70; and transmitting unit for ventilation16configured to wirelessly give operation instructions to each of ventilators70.

Receiving unit for ventilation15receives radio signals transmitted from transmitting units22of ceiling-embedded ventilation fan4and wall-mounted ventilation fan6, transmitting unit23of range hood fan5, and transmitting unit28of air supply device7.

Transmitting unit for ventilation16transmits radio signals, the radio signals indicating operations on which exhaust volume control unit11instructs the ventilators, to receiving units24of ceiling-embedded ventilation fan4and wall-mounted ventilation fan6, receiving unit25of range hood fan5, and receiving unit29of air supply device7.

Storage unit10includes target total exhaust volume storage unit14and exhaust capacity storage unit13, and is capable of reading information used for processing by exhaust volume control unit11, as necessary.

Via communication unit9such as receiving unit for broadband12or in-home network38, target total exhaust volume storage unit14acquires a target total exhaust volume for a house, the volume having been inputted to information input terminal8. In other words, for example, a user sets a target total exhaust volume for a house by making use of information input terminal8, so that the target total exhaust volume set by the user is stored in target total exhaust volume storage unit14. As a matter of course, the target total exhaust volume varies depending on, for example, the size of a house, the number of rooms thereof, the airtightness thereof, and the thermal insulating properties thereof. Hence, different values of the target total exhaust volume are set for different houses. The target total exhaust volume is a total volume of exhaust that should be discharged from a predetermined house within a predetermined time. The predetermined time used herein is, for example, one day (24 hours) or 3 hours, and thus varies depending on environments and agreements. Therefore, in the present embodiment, the predetermined time is a time that a user can arbitrarily set in accordance with laws and regulations, such as environmental standards and ventilation standards for a house in which ventilators70are installed, or environmental conditions specific to the house, and here, the predetermined time is 3 hours as an example.

Exhaust capacity storage unit13stores the exhaust capacity of at least one exhauster3connected to ventilation control device2. Examples of the exhaust capacity include the maximum exhaust volume per unit time of exhauster3. Furthermore, in the case where the exhaust capacity (exhaust setting) of exhauster3can be set at a plurality of levels, an exhaust capacity setting and an exhaust volume per unit time at the time of making this setting may correspond to each other and be stored as an exhaust capacity. Examples of the exhaust capacity setting include Rate 1, Rate 2, Weak, Medium, and Strong. The exhaust capacity may be inputted from, for example, information input terminal8, or may be acquired by an inquiry sent from exhaust volume control unit11to newly connected exhauster3, and stored in exhaust capacity storage unit13. For the purpose of balancing between an exhaust volume and an air supply volume as described later, exhaust capacity storage unit13may also store the air supply capacity of air supply device7as well as the exhaust capacity.

Exhaust volume control unit11includes exhaust volume acquisition unit17, integrating unit18, total remaining exhaust volume calculation unit19, shortest-exhaust-time calculation unit20, exhaust setting unit71, and calculation unit72.

Exhaust volume acquisition unit17acquires an already-discharged exhaust volume, that is, the volume of exhaust having been already discharged from each of exhausters3connected to ventilation control device2. Here, the already-discharged exhaust volume is acquired in the following manner, for example.

That is, at a timing when exhauster3starts exhaust, exhaust volume acquisition unit17receives an exhaust volume per unit time from exhauster3via communication unit9. Furthermore, at a timing when exhauster3changes an exhaust volume setting, exhaust volume acquisition unit17receives the changed exhaust volume per unit time from exhauster3via communication unit9. Furthermore, at a timing when exhauster3stops exhaust, exhaust volume acquisition unit17receives a notification about the stop from exhauster3via communication unit9. When receiving the data above, exhaust volume acquisition unit17multiplies the exhaust volume per unit time by a time period of operation with the exhaust volume to acquire a volume of exhaust having been already discharged by exhauster3.

As another method, exhaust volume acquisition unit17may send an inquiry about an already-discharged exhaust volume to each of exhausters3via communication unit9at predetermined time intervals. In response to this inquiry, each of exhausters3replies to the inquiry sent from exhaust volume acquisition unit17, via communication unit9, with the volume of exhaust having been already discharged between the previous inquiry and this inquiry.

When the above-described processing is performed for each of exhausters3connected to ventilation control device2, exhaust volume acquisition unit17can acquire the volume of exhaust having been already discharged from each of exhausters3.

Integrating unit18acquires, at predetermined time intervals, all the already-discharged exhaust volumes acquired by exhaust volume acquisition unit17, and adds up the volumes, in other words, integrates the volumes. Thus, total already-discharged exhaust volume43(seeFIG. 5) discharged from a house via all of exhausters3connected to ventilation control device2can be calculated.

Total remaining exhaust volume calculation unit19subtracts the total already-discharged exhaust volume calculated by integrating unit18from a target total exhaust volume per predetermined time that is stored in target total exhaust volume storage unit14, whereby total remaining exhaust volume44(seeFIG. 5), that is, a total exhaust volume short of the target total exhaust volume is calculated. Here, the calculation of total remaining exhaust volume44by total remaining exhaust volume calculation unit19is performed at a timing earlier than the elapse of the predetermined time set for the target total exhaust volume, as a matter of course.

Shortest-exhaust-time calculation unit20calculates shortest exhaust time45(seeFIG. 5), that is, a time required for achieving the target total exhaust volume when exhaust is performed with the maximum exhaust capacities of all of exhausters3connected to ventilation control device2, the capacities having been stored in exhaust capacity storage unit13.

Using the predetermined time required for achieving target total exhaust volume46(seeFIG. 5) and time B (seeFIG. 5) at which total already-discharged exhaust volume43is calculated, exhaust setting unit71calculates remaining time42(seeFIG. 5), that is, a remaining time until the elapse of the predetermined time set for achieving target total exhaust volume46. As illustrated inFIG. 5, remaining time42is calculated by subtracting the time elapsed from starting time point A to time B from time D serving as the predetermined time. Remaining time42is a time left to achieve target total exhaust volume46. Total remaining exhaust volume44, that is, a total exhaust volume short of target total exhaust volume46is calculated by total remaining exhaust volume calculation unit19. Thus, based on remaining time42and total remaining exhaust volume44, ventilation control device2can determine, for example, how much average exhaust volume is required for operating exhausters3during remaining time42. Note that, details about how to operate exhausters3during remaining time42will be described later, but, for example, there may be employed a control pattern in which all of exhausters3are operated at the maximum exhaust airflow rate until the remaining exhaust volume of air is discharged. This allows target total exhaust volume46to be achieved in the shortest time. As a matter of course, if there are no other restrictions, exhausters3are operated during remaining time42preferably with high energy efficiency, that is, with reduced energy. In this case, calculation unit72makes a calculation to determine an optimal control pattern of each of ventilators70, based on the energy consumption and exhaust airflow rate of each of ventilators70. When the control pattern is determined, exhaust setting unit71transmits an operation command to each of ventilators70via transmitting unit for ventilation16to control each of ventilators70.

Note that coordinated operations between units will be described later using a flowchart.

As illustrated inFIG. 4, ventilation control device2is provided as microcomputer40. Microcomputer40includes central processing unit (CPU)31, random access memory (RAM)32, and read only memory (ROM)33inside the microcomputer40, and further includes hard disk drive (HDD)34as storage unit10. Microcomputer40further includes wired communication module37and wireless communication module36. Wired communication module37and wireless communication module36each function as communication unit9, and are connected to CPU31, RAM32, ROM33, and HDD34via internal bus41. For example, CPU31makes use of RAM32as a workspace, executes a program stored in ROM33, and transmits and receives data and commands to/from storage unit10and devices, based on the result of the program execution, thereby controlling the operation of the devices.

Exhaust volume control unit11and the units belonging to exhaust volume control unit11function as programs stored in ROM33, and execute predetermined processing when executed by CPU31. HDD34, ROM33, and RAM32are not necessarily required to be used, and other types of memories may be used instead.

Devices such as wireless communication module36and wired communication module37are not necessarily provided in microcomputer40, and may be externally connected.

[Exhauster and Air Supply Device]

Ceiling-embedded ventilation fan4and wall-mounted ventilation fan6, which are examples of exhauster3, each include transmitting unit22, receiving unit24, and storage unit26. Range hood fan5includes transmitting unit23, receiving unit25, and storage unit27. Air supply device7includes transmitting unit28, receiving unit29, and storage unit30.

Transmitting unit22of ceiling-embedded ventilation fan4reads, from storage unit26, information to be provided, and transmits the information to ventilation control device2via in-home network38by wireless communication.

Storage unit26stores information to be provided, the information being possibly required from ventilation control device2. Examples of the provided information that storage unit26stores include, but are not limited to, an operation state indicating whether or not ceiling-embedded ventilation fan4is in operation, an exhaust volume setting (for example, weak, medium, strong) of ceiling-embedded ventilation fan4in operation, and an exhaust airflow volume per unit time that corresponds to the exhaust volume setting.

Note that not only ceiling-embedded ventilation fan4, but also wall-mounted ventilation fan6, range hood fan5, air supply device7, and other various exhausters and air supply devices, each being connected to ventilation control device2to carry out a function, basically have the above-mentioned configuration.

In-home network38configured to connect ventilation control device2, exhauster3, and air supply device7is, for example, digital enhanced cordless telecommunications or wireless communications using a Wi-FI (registered trademark) system.

Next, the operations of ventilation control device2will be described with reference toFIG. 3,FIG. 5, andFIG. 6. Note thatFIG. 5is a graph illustrating an operation example of the ventilators controlled by the ventilation control device according to the present embodiment.FIG. 6is a flowchart illustrating information processing by the ventilation control device according to the present embodiment. InFIG. 6, S represents a step. Note that steps are not necessarily implemented in ascending order of number.

Ventilation control device2is configured such that target total exhaust volume46set beforehand by information input terminal8and predetermined time D (corresponding to the predetermined time, namely, 3 hours in the present embodiment) to achieve target total exhaust volume46are stored in storage unit10.

Ventilation control device2starts a timer at starting time point A to start the control of exhaust airflow rate (S101). Time D is a time point at which 3 hours have been elapsed from starting time point A. After the timer reaches time D, the timer is reset, and started again from 0. These operations are repeated as a routine work as long as there is no change in the setting of time D.

Here, it is assumed that, in accordance with user's intention, wall-mounted ventilation fan6is operated at an exhaust airflow rate of 30 cfm from starting time point A, that is, a time for starting the timer, until time B, and stopped at time B. In this case, the time and exhaust airflow rate (30 cfm) at starting time point A and the time and exhaust airflow rate (0 cfm) at time B are transmitted, at the respective timings of starting time point A and time B, from transmitting unit22to exhaust volume acquisition unit17via receiving unit for ventilation15.

Based on the transmitted information, exhaust volume acquisition unit17calculates the volume of exhaust already discharged between starting time point A and time B, and transmits the calculation result to integrating unit18. The calculation is performed at predetermined time intervals (for example, at one-second intervals), assuming that the operation goes on under the already-given condition (the exhaust airflow rate (30 cfm)) also between starting time point A and time B inclusive during which information from ventilator70has not been given.

Integrating unit18calculates total already-discharged exhaust volume43by adding up the already-discharged exhaust volumes acquired by exhaust volume acquisition unit17(S102). Here, only wall-mounted ventilation fan6is operated, which means that the already-discharged exhaust volume of wall-mounted ventilation fan6is equal to total already-discharged exhaust volume43.

Note that exhaust volume control unit11always monitors whether or not total already-discharged exhaust volume43has reached target total exhaust volume46(S103).

Here, in the case where total already-discharged exhaust volume43has not reached target total exhaust volume46, total remaining exhaust volume calculation unit19calculates total remaining exhaust volume44from the difference between total already-discharged exhaust volume43and target total exhaust volume46(No at S103S104). Shortest-exhaust-time calculation unit20calculates shortest exhaust time45necessary for exhaust in total remaining exhaust volume44with the maximum exhaust capacities of exhausters3connected to ventilation control device2(S105). Note that the maximum exhaust capacity of ceiling-embedded ventilation fan4is 150 cfm, the maximum exhaust capacity of wall-mounted ventilation fan6is 30 cfm, and the maximum exhaust capacity of range hood fan5is 150 cfm.

Subsequently, exhaust setting unit71compares shortest exhaust time45with remaining time42until time D (S106). Here, at the point of time B, in the case where remaining time42is sufficiently longer than shortest exhaust time45, exhaust setting unit71determines to maintain the present exhaust capacity (No at S106→S102).

Subsequently, it is assumed that, while a user has not operated ventilators70, the time reaches time C at which remaining time42becomes equal to shortest exhaust time45. In this case, exhaust setting unit71instructs, via transmitting unit for ventilation16, each of exhausters3to forcibly start an exhaust operation at the maximum exhaust airflow rate (forced shortest-exhaust operation) (Yes at S106→S107).

Here, in the above-described processing, the comparison between shortest exhaust time45and remaining time42is performed to determine whether to start the forced shortest-exhaust operation (S106), but, for example, a comparison between total remaining exhaust volume44and the maximum exhaustible total volume (not illustrated) obtained by multiplying the maximum exhaust capacities of exhausters3by remaining time42may be performed. In this case, when the maximum exhaustible total volume is larger than total remaining exhaust volume44, the status quo is maintained. In contrast, when the maximum exhaustible total volume is equivalent to or smaller than total remaining exhaust volume44, the forced shortest-exhaust operation is started to achieve the same effect.

In accordance with the above-described instruction, ceiling-embedded ventilation fan4, wall-mounted ventilation fan6, and range hood fan5start an operation at time C at the maximum exhaust airflow rate, namely, at 150 cfm, 30 cfm, and 150 cfm, respectively. With this operation, target total exhaust volume46is achieved at time D (repetition of S107→S102→S103).

After that, when the timer reaches time D and total remaining exhaust volume44and remaining time42become 0, whereby it is determined that target total exhaust volume46has been achieved, then exhaust setting unit71stops the forced shortest-exhaust-operation, and at the same time, resets the timer and the total already-discharged exhaust volume at 0 (S103→S108→S109→S112).

InFIG. 6, the forced shortest-exhaust-operation is performed between time C and time D, that is, in the last part of the remaining time42of the predetermined 3 hours. However, there can be assumed a case in which, in accordance with user's intention, any one or a plurality of exhausters3operates between time B and time C, so that target total exhaust volume46is achieved before the forced shortest-exhaust-operation is performed. In this case, exhaust setting unit71instructs exhausters3not to perform the forced shortest-exhaust-operation, but to maintain the status quo (S108→S110). Then, at the time when 3 hours have elapsed, the timer and total already-discharged exhaust volume43are reset at 0 (Yes at S111→S112).

The above-described processing allows ventilation control device2according to the present embodiment to control the operation of exhausters3so as to achieve target total exhaust volume46within the predetermined time. Furthermore, when a total exhaust volume owing to the operation of all of connected exhausters3for the predetermined 3 hours is counted and the total exhaust volume is controlled so as not to considerably exceed target total exhaust volume46, then energy saving effects can be achieved.

When air supply device7receives, from ventilation control device2via receiving unit29, information on the total volume of exhaust from exhausters3(ceiling-embedded ventilation fan4, wall-mounted ventilation fan6, and range hood fan5), air supply device7operates to supply air in an air supply volume equivalent to the total exhaust volume to a house. This operation of air supply device7aims to attain a balance between an exhaust volume and an air supply volume, and offers the effect of preventing an extremely negative pressure from being caused in a house.

FIG. 7is a diagram illustrating provided information on the ventilator according to the present embodiment. In the present embodiment, examples of provided information47dealt in storage unit26, storage unit27, and storage unit30of the above-described ventilators70, such as ceiling-embedded ventilation fan4and wall-mounted ventilation fan6, are operation states and exhaust airflow rates. However, as illustrated inFIG. 7, product information58specific to ventilator70and present information59on ventilator70may be configured to be transmitted as provided information47to ventilation control device2. Here, product information58includes, for example, product ID51, exhaust capacity52of ventilator70indicating settable airflow rates, and on-board sensor53indicating the type of a sensor installed into ventilator70. Present information59include, for example, present airflow rate54indicating a present operation state, sensor state55indicating a detection state of the on-board sensor, forced operation56indicating whether or not a user forcibly operates the ventilator, and power consumption57indicating power consumption at the present airflow rate. Based on product information58specific to ventilators70and present information59thereof, calculation unit72can grasp, for example, electrical characteristics of each of connected ventilators70, and select a combination of ventilators70that achieves the minimum power consumption. Thus, ventilation control device2can not only achieve target total exhaust volume46, but also realize exhaust control to reduce power consumption.

FIG. 8is a diagram illustrating combinations of the ventilators, the combinations being selected by the ventilation control device according to the present embodiment.FIG. 8illustrates combinations of ventilators70in the case where an exhaust airflow rate necessary in a house for a predetermined time is set at 250 cfm. In this case, using information on the airflow rates and power consumption of ventilators70, calculation unit72selects optimal combination65that achieves the minimum power consumption, so that ventilators70can be controlled.

INDUSTRIAL APPLICABILITY

As described above, the ventilation control device according to the present disclosure can conduct processing for determining ventilators connected to the ventilation control device and conditions for the most efficient and shortest driving of the ventilators in accordance with the state of usage of the ventilators, and hence, the ventilation control device are applicable to, for example, stand-alone houses and multifamily dwelling houses such as apartments.

REFERENCE MARKS IN THE DRAWINGS