JP7146089B2 - Heat exchange ventilator and control method for heat exchange ventilator - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat exchange ventilator that performs ventilation while exchanging heat between an intake air flow and an exhaust air flow, and a control method for the heat exchange ventilator.

Conventionally, a heat exchange ventilator has had a problem that water condensed inside the heat exchange ventilator flows out of the heat exchange ventilator when outside air is taken in when fog is generated.

Patent Document 1 discloses a heat exchange ventilator that detects the state of outside air taken into a supply air passage by a sensor, and stops or intermittently operates the supply air blower when the humidity of the outside air exceeds a standard. disclosed. The heat exchange ventilator according to Patent Literature 1 prevents fog from entering the supply air passage by stopping the supply of air or switching the supply of air to intermittent supply of air.

JP 2009-293880 A

The humidity of the outside air increases not only when the outside air becomes highly humid air due to the occurrence of fog, but also when it rains during the day. Since the conventional heat exchange ventilator according to Patent Document 1 determines whether to continue or stop the air supply based on the humidity of the outside air, the ventilation may stop even when it rains.

In addition, in conventional heat exchange ventilators, when the indoor pressure is negative, even if ventilation is stopped, outside air flows into the supply air passage due to the pressure difference between the inside and outside of the heat exchange ventilator. can cause water to flow into For this reason, the conventional heat exchange ventilator requires measures such as eliminating the negative pressure in the room or preventing the inflow of outside air using a damper or the like.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat exchange ventilator capable of suppressing outflow of water when high-humidity air enters a supply air passage.

In order to solve the above-described problems and achieve the object, the heat exchange ventilation device according to the present invention includes a supply air blower that takes in outdoor air and sends the taken in indoor air, and a supply air blower that takes in indoor air and takes in the air. A heat exchanger that exchanges heat between the supply air flow generated by the supply air blower and the exhaust flow generated by the exhaust blower, and the amount of moisture contained in the heat exchanger and a ventilation controller for controlling the supply air blower and the exhaust air blower based on. The ventilation control unit performs dry operation when the moisture content is greater than a preset first threshold, and in dry operation, stops the operation of the supply air blower or lowers the wind speed compared to ventilation operation. The supply air blower is operated and the exhaust air blower is operated.

ADVANTAGE OF THE INVENTION The heat exchange ventilator according to the present invention has the effect of being able to suppress the outflow of water when high-humidity air enters the supply air passage.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows the heat exchange ventilator concerning Embodiment 1 of this invention. 1 is a diagram schematically showing the inside of the heat exchange ventilator according to the first embodiment; FIG. FIG. 2 is a diagram showing a heat exchanger and guide rails in the heat exchange ventilator according to the first embodiment; FIG. 2 is a block diagram showing the functional configuration of the control device of the heat exchange ventilator according to the first embodiment; 4 is a flow chart showing the operation procedure of the heat exchange ventilator according to the first embodiment. FIG. 1 is a first diagram showing an example of a hardware configuration of a controller included in the heat exchange ventilator according to the first embodiment; FIG. 2 is a second diagram showing an example of the hardware configuration of the control device of the heat exchange ventilator according to the first embodiment; A block diagram showing a functional configuration of a control device of a heat exchange ventilator according to Embodiment 2 of the present invention.

A heat exchange ventilator and a heat exchange ventilator control method according to embodiments of the present invention will be described in detail below with reference to the drawings. In addition, this invention is not limited by this embodiment.

Embodiment 1.
FIG. 1 is a perspective view showing a heat exchange ventilator according to Embodiment 1 of the present invention. FIG. 2 is a diagram schematically showing the inside of the heat exchange ventilator according to the first embodiment. The heat exchange ventilator 1 is a device that performs ventilation while exchanging heat between an air supply flow and an exhaust air flow. The heat exchange ventilator 1 maintains a comfortable air environment in the room by ventilating the room by supplying air from the outdoors to the room and exhausting air from the room to the outside. In addition, the heat exchange ventilator 1 reduces the temperature difference between the air taken into the room and the air in the room by heat exchange between the supply air flow and the exhaust air flow, thereby reducing the burden of air conditioning in the room. The heat exchange ventilator 1 is installed in the space behind the ceiling.

A heat exchange ventilator 1 has a supply air blower 11 for taking in outdoor air and sending the taken in air indoors, and an exhaust air blower 12 for taking in indoor air and sending the taken in air outside. The supply air blower 11 generates an air supply flow by rotating a fan inside the fan casing 7 . The exhaust blower 12 generates an exhaust flow by rotating a fan within the fan casing 8 . Illustration of the fan is omitted in FIG.

The heat exchange ventilator 1 comprises a heat exchanger 2 for exchanging heat between the supply air stream and the exhaust air stream. The supply air blower 11 , the exhaust air blower 12 and the heat exchanger 2 are housed in the casing 5 . Casing 5 is a hexahedron including top plate 3 and bottom plate 4 . Inside the casing 5, there are provided an air supply passage through which an air supply flow passes, an exhaust air passage through which an exhaust air flow passes, and partition walls 17 and 18 that separate the supply air passage and the exhaust air passage. FIG. 1 shows the heat exchange ventilator 1 with the top plate 3 removed from the casing 5 . In addition, in Embodiment 1, the heat exchange ventilator 1 shall be installed with the top plate 3 facing vertically upward.

A supply air inlet 13 and an exhaust air outlet 14 are provided on one side surface of the casing 5 . A supply air outlet 15 and an exhaust air suction port 16 are provided on a side surface of the casing 5 opposite to the side surface. Outside air is taken into the supply air passage through the supply air suction port 13 . The outside air taken into the air supply passage passes through the air supply passage and is blown into the room from the air supply outlet 15 . Indoor air is taken into the exhaust air passage through the exhaust suction port 16 . The air taken into the exhaust air passage passes through the exhaust air passage and is blown out of the room from the exhaust outlet 14 .

Heat exchanger 2 performs total heat exchange between the supply air stream and the exhaust air stream. The heat exchanger 2 has a primary side air passage through which the exhaust flow passes and a secondary side air passage through which the supply air flow passes. Inside the heat exchanger 2, the primary air passage and the secondary air passage intersect perpendicularly. The primary side air passage and the secondary side air passage are formed in a laminated body configured by alternately adhering flat sheets of paper and corrugated sheets of corrugated paperboard. In FIG. 1, illustration of the primary side air passage and the secondary side air passage is omitted. The laminate has a quadrangular prism shape. The end surfaces of the heat exchanger 2 located at both ends in the stacking direction are square. The heat exchanger 2 has four ridges parallel to the stacking direction. The heat exchanger 2 is accommodated in the casing 5 so that each ridgeline portion faces the top plate 3, the bottom plate 4, the partition wall 17 and the partition wall 18, respectively.

A maintenance cover is provided on the front surface of the casing 5, which is one of the side surfaces other than the side surface having the air supply inlet 13 and the exhaust air outlet 14 and the side surface having the air supply outlet 15 and the exhaust air inlet 16. 6 and a control device 9 are provided. Maintenance cover 6 is provided at a position facing one end surface of heat exchanger 2 . By opening the maintenance cover 6, the heat exchanger 2 can be pulled out from the casing 5 to the outside and can be inserted into the casing 5 from the outside. The control device 9 controls the entire heat exchange ventilator 1 .

Guide rails 21 , 22 , 23 , and 24 that support the heat exchanger 2 are provided inside the casing 5 . A guide rail 21 is provided on the top plate 3 . One of the four ridges directed toward the top plate 3 is inserted into the guide rail 21 . The guide rails 22 are provided on the bottom plate 4 . One of the four ridges directed toward the bottom plate 4 is inserted into the guide rail 22 . The guide rail 23 is provided on the partition wall 17 . One of the four ridges facing the partition wall 17 is inserted into the guide rail 23 . The guide rail 24 is provided on the partition wall 18 . One of the four ridges facing the partition wall 18 is inserted into the guide rail 24 . By moving the heat exchanger 2 along the guide rails 21 , 22 , 23 , 24 with the maintenance cover 6 open, the heat exchanger 2 is pulled out and inserted.

The heat exchange ventilator 1 operates the supply air blower 11 and the exhaust air blower 12 in normal ventilation operation. In addition, the heat exchange ventilator 1 dries the inside of the casing 5 by performing a drying operation when a situation arises in which condensed water may be generated inside the casing 5 by taking in outside air when fog is generated. . In the drying operation, the heat exchange ventilator 1 stops the operation of the supply air blower 11 and operates the exhaust air blower 12 . Based on the amount of water contained in the heat exchanger 2 , the control device 9 determines whether or not a situation has arisen in which condensed water may occur inside the casing 5 . The control device 9 detects the amount of water based on the amount of change in the weight of the heat exchanger 2 .

FIG. 3 is a diagram showing a heat exchanger and guide rails in the heat exchange ventilator according to the first embodiment. A weight sensor 25 is provided on the guide rail 22 . Weight sensor 25 detects the weight of heat exchanger 2 . The weight sensor 25 is provided at a position of the guide rail 22 in contact with the heat exchanger 2 . In Embodiment 1, weight sensor 25 has a resistor and a strain gauge. The strain gauge detects the weight of the heat exchanger 2 by measuring the strain generated in the resistor by receiving the gravity of the heat exchanger 2 .

4 is a block diagram of a functional configuration of a control device included in the heat exchange ventilator according to the first embodiment; FIG. The control device 9 includes an input unit 31 to which information from the outside of the control device 9 is input, a water content detection unit 32 for detecting the water content contained in the heat exchanger 2, and based on the detected water content and a ventilation control unit 33 for controlling the supply air blower 11 and the exhaust air blower 12 .

The weight detection result of the weight sensor 25 is input to the input unit 31 . The input unit 31 outputs the input information to the water content detection unit 32 . The water content detector 32 detects the amount of change in the weight of the heat exchanger 2 due to the increase in the water content in the heat exchanger 2 . The water content detector 32 detects the amount of water contained in the heat exchanger 2 by detecting the amount of change in the weight of the heat exchanger 2 . The water content detection unit 32 outputs the detection result of the water content to the ventilation control unit 33 .

The ventilation control unit 33 determines whether or not the drying operation is necessary based on the detection result of the moisture content. When determining that the drying operation is necessary, the ventilation control unit 33 outputs a control signal for the drying operation to the supply air blower 11 and the exhaust air blower 12 to start the drying operation. In the drying operation, the heat exchange ventilator 1 stops air blowing by the supply air blower 11 and blows air by the exhaust air blower 12 . The heat exchange ventilator 1 dries the inside of the casing 5 by the drying operation.

Next, the operation of the heat exchange ventilator 1 will be described. FIG. 5 is a flow chart showing operation procedures of the heat exchange ventilator according to the first embodiment.

In step S<b>1 , the water content detector 32 detects the water content in the heat exchanger 2 . The water content detection unit 32 acquires the weight detection result of the heat exchanger 2 from the input unit 31 . The controller 9 holds an initial value, which is the weight of the heat exchanger 2 in a moisture-free state. The moisture content detector 32 calculates the moisture content by subtracting the initial value from the detected weight. Initial values set as default values are stored in advance in the control device 9 . The control device 9 may store the weight value detected by the weight sensor 25 during construction of the heat exchange ventilator 1 as an initial value.

In step S2, the ventilation control unit 33 determines whether or not the detected water content is greater than the first threshold. The first threshold is the amount of water that can form water droplets due to condensation of the water contained in the heat exchanger 2 . A first threshold value is stored in advance in the control device 9 . If the detected moisture content is equal to or less than the first threshold (step S2, No), the control device 9 returns the procedure to step S1.

If the detected moisture content is greater than the first threshold (step S2, Yes), in step S3, the ventilation control unit 33 determines whether the heat exchange ventilator 1 is in ventilation operation. If the heat exchange ventilator 1 is in the ventilation operation (step S3, Yes), the ventilation control unit 33 stops the supply air blower 11 and continues the operation of the exhaust air blower 12 in step S4. Thereby, the heat exchange ventilator 1 starts the drying operation. When the heat exchange ventilator 1 is not in the ventilation operation (step S3, No), the ventilation control unit 33 starts the operation of the exhaust air blower 12 in step S5. Thereby, the heat exchange ventilator 1 starts the drying operation. After starting the drying operation in step S4 or step S5, the heat exchange ventilator 1 proceeds to step S6.

In step S6, the water content detection unit 32 detects the water content after the drying operation is started in step S4 or step S5. In step S6, the water content detector 32 detects the water content in the same manner as in step S1. In step S7, the ventilation control unit 33 determines whether or not the detected water content is less than the second threshold. The second threshold is a value at which it can be assumed that the moisture contained in the heat exchanger 2 has been removed by evaporation. A second threshold value is stored in advance in the control device 9 . If the detected moisture content is equal to or greater than the second threshold (step S7, No), the ventilation control unit 33 continues the operation of the exhaust air blower 12 in step S9. That is, the heat exchange ventilator 1 continues the drying operation. After that, the control device 9 returns the procedure to step S7.

If the detected moisture content is less than the second threshold (step S7, Yes), in step S8, the ventilation control unit 33 restores the operating states of the supply air blower 11 and the exhaust air blower 12 to their original operating states. The ventilation control unit 33 starts the operation of the supply air blower 11 and continues the operation of the exhaust air blower 12 when it is determined that the ventilation operation is being performed in step S3. As a result, the heat exchange ventilator 1 ends the drying operation and returns to the ventilation operation. Further, when it is determined in step S3 that the ventilation operation is not being performed, the ventilation control unit 33 stops the operation of the exhaust air blower 12 and keeps the supply air blower 11 stopped. As a result, the heat exchange ventilator 1 ends the drying operation and returns to the shutdown state. As described above, the heat exchange ventilator 1 completes the operation according to the procedure shown in FIG.

Note that a plurality of mutually different values may be set for the first threshold in step S2. For example, when a first value and a second value larger than the first value are set as the first threshold, the ventilation control unit 33 sets the detected water content to the first and the second value, and control may be performed according to the result of the comparison. When the moisture content is greater than the first value and the moisture content is equal to or less than the second value, the ventilation control unit 33 operates the supply air blower 11 at a lower wind speed than during the ventilation operation. Also good. Also, the ventilation control unit 33 may stop the operation of the supply air blower 11 when the moisture content is greater than the second value.

With the above operation, the heat exchanging ventilator 1 can suppress water from flowing out of the casing 5 by performing the drying operation in a situation where condensed water may occur inside the casing 5 . The heat exchange ventilator 1 determines whether or not the drying operation is necessary based on the amount of water contained in the heat exchanger 2, thereby avoiding stoppage of ventilation when it rains. In addition, the heat exchange ventilator 1 can suppress the outflow of water to the outside of the casing 5 without taking measures such as installing an outdoor hood for preventing intrusion of fog.

The heat exchange ventilator 1 performs a drying operation even when ventilation is stopped, when condensed water may be generated inside the casing 5 . For this reason, in the heat exchange ventilator 1, water flows out of the casing 5 even when the indoor pressure is negative and high-humidity air enters the supply air passage even when the ventilation operation is stopped. can be suppressed. The heat exchanging ventilator 1 allows the air flow to the outside of the casing 5 when the ventilation operation is stopped without taking measures such as eliminating the negative pressure in the room or installing a damper to prevent the inflow of outside air. Outflow of water can be suppressed.

Next, the hardware configuration of the control device 9 will be described. The functions of the controller 9 are implemented using processing circuitry. The processing circuit is dedicated hardware installed in the heat exchange ventilator 1 or a processor that executes a program stored in a memory.

6 is a first diagram illustrating an example of a hardware configuration of a control device included in the heat exchange ventilator according to the first embodiment; FIG. FIG. 6 shows the hardware configuration when the functions of the control device 9 are realized using dedicated hardware. The control device 9 includes a processing circuit 41 that executes various processes, and an interface 42 that is an interface for connecting the control device 9 to external devices.

The processing circuit 41, which is dedicated hardware, is a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or any of these It's a combination. Each function of the moisture content detection unit 32 and the ventilation control unit 33 is realized using the processing circuit 41 . The processing circuit 41 also has a memory that stores the initial value, the first threshold value, and the second threshold value described above. The function of the input section 31 is implemented using the interface 42 . A signal from the weight sensor 25 is input to the interface 42 . The interface 42 also outputs control signals to the supply air blower 11 and the exhaust air blower 12 .

7 is a second diagram illustrating an example of a hardware configuration of a control device included in the heat exchange ventilator according to the first embodiment; FIG. FIG. 7 shows a hardware configuration when the functions of the control device 9 are implemented using hardware that executes programs. The control device 9 has a processor 43 , a memory 44 and an interface 42 .

The processor 43 is a CPU (Central Processing Unit). The processor 43 may be a processing device, an arithmetic device, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor). Each function of the water content detection unit 32 and the ventilation control unit 33 is realized by the processor 43, software, firmware, or a combination of software and firmware. Software or firmware is written as a program and stored in memory 44, which is an internal memory. Also, the memory 44 stores the initial value, the first threshold value, and the second threshold value described above. The memory 44 is a nonvolatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), or EEPROM (Electrically Erasable Memory). Programmable Read Only Memory).

In the heat exchange ventilator 1 , the weight sensor 25 may be provided on elements other than the guide rails 22 . The weight sensor 25 should just be installed so that the weight of the heat exchanger 2 can be detected. When the heat exchange ventilator 1 is installed upside down from the case shown in FIG. , are provided on the guide rail 21 . The weight sensor 25 is installed on the guide rail 23 when the heat exchange ventilator 1 is installed such that the side surface on which the air supply inlet 13 and the exhaust air outlet 14 are provided faces vertically downward. The weight sensor 25 is installed on the guide rail 24 when the heat exchange ventilator 1 is installed such that the side surface on which the supply air outlet 15 and the exhaust air inlet 16 are provided faces vertically downward. In order to change the position of the weight sensor 25 according to the attitude of the heat exchange ventilator 1 when the heat exchange ventilator 1 is installed, a plurality of elements may be replaceable.

Furthermore, when the heat exchange ventilator 1 is installed by being suspended from above vertically, the weight sensor 25 may be provided on a metal fitting or the like for ceiling suspension. Thus, the weight sensor 25 is not limited to being provided inside the casing 5 and may be provided outside the casing 5 .

According to Embodiment 1, the heat exchange ventilator 1 detects the amount of water contained in the heat exchanger 2, and controls the supply air blower 11 and the exhaust air blower 12 based on the detected amount of water. The heat exchange ventilator 1 performs drying operation in a situation where condensed water may be generated inside the casing 5 by taking in outside air at the time of fog generation, and high humidity air enters the supply air passage. Also, the outflow of water to the outside of the casing 5 can be suppressed. As a result, the heat exchange ventilator 1 has the effect of being able to suppress the outflow of water when high-humidity air enters the supply air passage.

Embodiment 2.
FIG. 8 is a block diagram showing a functional configuration of a control device included in the heat exchanging ventilator according to Embodiment 2 of the present invention. The heat exchange ventilator 1 according to the second embodiment detects the amount of moisture based on changes in electrical characteristics of the heat exchanger 2 . In the second embodiment, the same reference numerals are assigned to the same components as in the first embodiment, and the configuration different from the first embodiment will be mainly described.

The heat exchange ventilator 1 has an electrical measuring device 26 for measuring electrical characteristics of the heat exchanger 2 . The electrical measuring device 26 is connected to a pair of electrodes provided at both ends of the heat exchanger 2 . In FIG. 8, illustration of electrodes is omitted. The electrical measuring device 26 measures the internal capacitance of the heat exchanger 2 . The electrical measuring device 26 outputs the capacitance measurement result to the control device 9 .

The input unit 31 receives the measurement result of the capacitance. The water content detection unit 32 detects the amount of change in capacitance due to an increase in the amount of water contained in the heat exchanger 2 . The water content detection unit 32 detects the water content based on changes in capacitance inside the heat exchanger 2 .

Note that the water content detection unit 32 may detect the water content based on changes in electrical conductivity inside the heat exchanger 2 . In this case, the electrical measuring device 26 measures the electrical conductivity inside the heat exchanger 2 . The input unit 31 receives the measurement result of conductivity. The water content detector 32 detects the amount of change in electrical conductivity due to an increase in the water content in the heat exchanger 2 . Also in this case, the water content detection unit 32 can detect the water content contained in the heat exchanger 2 .

Also in the second embodiment, the heat exchanging ventilator 1 can suppress the outflow of water when high-humidity air enters the supply air passage.

The configuration shown in the above embodiment shows an example of the content of the present invention, and it is possible to combine it with another known technology, and one configuration can be used without departing from the scope of the present invention. It is also possible to omit or change the part.

1 heat exchange ventilator, 2 heat exchanger, 3 top plate, 4 bottom plate, 5 casing, 6 maintenance cover, 7, 8 fan casing, 9 control device, 11 supply air blower, 12 exhaust air blower, 13 air supply inlet, 14 exhaust outlet, 15 supply air outlet, 16 exhaust inlet, 17, 18 partition wall, 21, 22, 23, 24 guide rail, 25 weight sensor, 26 electrical measuring device, 31 input unit, 32 water content detection Section 33 Ventilation Control Section 41 Processing Circuit 42 Interface 43 Processor 44 Memory.

Claims (9)

a supply air blower that takes in outdoor air and sends the taken in air indoors;
an exhaust fan that takes in the air in the room and sends the taken in air to the outside of the room;
a heat exchanger that exchanges heat between a supply air flow generated by the supply air blower and an exhaust flow generated by the exhaust blower;
a ventilation control unit that controls the supply air blower and the exhaust air blower based on the amount of moisture contained in the heat exchanger;
with
The ventilation control unit performs a drying operation when the moisture content is greater than a preset first threshold, and in the drying operation, the operation of the supply air blower is stopped, or the wind speed is lowered to operate the supply air blower and to operate the exhaust air blower . A moisture content detection unit that detects the amount of moisture contained in the heat exchanger,
2. The heat exchange ventilator according to claim 1, wherein the ventilation control unit controls the supply air blower and the exhaust air blower based on the moisture content detected by the moisture content detection unit. 3. The heat exchange ventilator according to claim 2, wherein the moisture content detection unit detects the moisture content by detecting a change in weight of the heat exchanger. 3. The heat exchange ventilator according to claim 2, wherein the moisture content detection unit detects the moisture content based on changes in electrical characteristics of the heat exchanger. 5. The heat exchange ventilator according to claim 4, wherein the moisture content detection unit detects the moisture content based on a change in capacitance inside the heat exchanger. 5. The heat exchange ventilator according to claim 4, wherein the moisture content detection unit detects the moisture content based on a change in electrical conductivity inside the heat exchanger. 7. The ventilation control unit terminates the drying operation when the moisture content becomes less than a preset second threshold after the drying operation is started . The heat exchange ventilator according to any one of . Having a weight sensor that detects the weight of the heat exchanger,
4. The weight sensor according to claim 3, wherein the weight sensor is a strain gauge that detects the weight of the heat exchanger by measuring the strain generated in the resistor by receiving the gravity of the heat exchanger. A heat exchange ventilator as described. heat exchange between a supply airflow generated by taking in outdoor air and sending the taken-in air into the room, and an exhaust flow generated by taking in the indoor air and sending the taken-in air to the outdoor A method for controlling a heat exchange ventilator having a heat exchanger that performs
detecting the amount of moisture contained in the heat exchanger;
controlling air supply and exhaust based on the detected moisture content;
including
Drying operation is performed when the water content is greater than a preset first threshold value, and in the drying operation, the air supply is stopped, or the air supply is performed by reducing the wind speed compared to the ventilation operation. and performing the exhaust .

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