JP2015190684A - Heat exchange type ventilation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchange type ventilation device capable of continuing air supply/exhaustion while suppressing freezing of a heat exchange element, while eliminating a temperature sensor.SOLUTION: A control unit 11 stores a current value of a motor for exhaustion for outputting a predetermined air amount in a predetermined external static pressure of the motor for exhaustion at operation start time, and when the present operation current value of the motor for exhaustion becomes equal to or greater than a predetermined value, it detects that clogging inside a heat exchange element part 6 is occurring, and reduces rotational frequency of a motor for air supply. Thereby, a heat exchange type ventilation device 1 can be acquired which can continue the simultaneous operation of a blower 9 for air supply and a blower 10 for air exhaustion while preventing freezing of the heat exchange element part 6.

Description

  The present invention relates to a heat exchange type ventilator for exchanging heat between outside air and room air.

Conventionally, as this type of ventilator, a ventilator that is installed in a building, introduces outside air from an outside air supply port, and supplies the outside through a built-in heat exchange element is known. (For example, see Patent Document 1)
Hereinafter, the ventilation air conditioner will be described with reference to FIG.

  As shown in FIG. 6, the ventilator main body 101 is installed in an attic space or a ceiling space in a building. Fresh outside air is introduced from the outside air inlet 102, passes through the built-in heat exchange element 103, and is supplied to the room through the indoor inlet 104. On the other hand, the dirty air in the room is introduced from the indoor exhaust port 105, passes through the heat exchange element unit 103, and is exhausted to the outside through the outdoor exhaust port 106. Fresh fresh air introduced from the outside air supply port 102 and indoor dirty air introduced from the indoor exhaust port 105 are connected to the electric motor 107 through the heat exchange element unit 103 and connected to the electric motor 107 on the same shaft 108. And an exhaust fan 110 for transfer.

JP-A-11-325535

  Such a conventional heat exchange type ventilator has a problem that condensation of heat exchange elements occurs at low temperatures in winter. In order to prevent the heat exchange element from being frozen, intermittent operation is sometimes performed, but it is necessary to mount a temperature sensor, which has a problem of increasing the cost.

  Therefore, the present invention solves the above-described conventional problems, and provides a heat exchange type ventilator capable of continuing supply / exhaust ventilation while suppressing freezing of a heat exchange element while eliminating a temperature sensor. Objective.

  In order to achieve this object, the present invention provides an air supply fan having an air supply motor, an exhaust fan having an exhaust motor, and the air supply fan for blowing air from the outside to the room. The indoor air and the outdoor air are ventilated at a position where the supply air blowing path, the exhaust fan blowing air from the room to the outside by the exhaust fan, and the supply air blowing path and the exhaust air blowing path intersect. In a heat exchange ventilator comprising a heat exchanging element for exchanging heat when performing the operation, and a controller for controlling the operation and rotation speed of the air supply motor and the exhaust motor, the current flowing through the exhaust motor The control unit further stores an exhaust motor current value for outputting a predetermined air volume at a predetermined external static pressure of the exhaust motor at the start of operation, and the control unit stores the exhaust motor at a predetermined air volume. Driving in When the current operating current value of the exhaust motor becomes larger than a predetermined value when compared with the stored operating current value, it is detected that clogging has occurred inside the heat exchange element. Then, the number of rotations of the air supply motor is reduced, thereby achieving the intended purpose.

  According to the present invention, an air supply fan provided with an air supply motor, an exhaust fan provided with an exhaust motor, an air supply air passage that is blown indoors from the outside by the air supply fan, For exchanging heat when ventilating indoor air and outdoor air at a position where the exhaust air blowing path blown from the room to the outside by the exhaust fan, and the supply air blowing path and the exhaust air blowing path intersect. In the heat exchange type ventilator comprising a heat exchange element and a controller for controlling the operation and rotation speed of the air supply motor and the exhaust motor, a current detection means for measuring a current flowing through the exhaust motor is further provided. And the controller stores an exhaust motor current value for outputting a predetermined air volume at a predetermined external static pressure of the exhaust motor at the start of operation, and when the exhaust motor is continuously operated at a predetermined air volume, For exhaust When the operating current value of the motor becomes greater than a predetermined value compared with the stored operating current value, it is detected that clogging has occurred inside the heat exchange element, and the By reducing the rotation speed, it detects that the heat exchange element has started freezing without attaching a temperature sensor, and by reducing the rotation speed of the air supply motor to prevent freezing, While preventing the heat exchange element from freezing, it is possible to continue the simultaneous operation of the supply air and the exhaust, and it is possible to obtain the effect of melting the freezing of the heat exchange element by increasing the exhaust temperature by the excessive exhaust operation.

Top sectional drawing which shows the heat exchange type | formula ventilation apparatus of embodiment of this invention Relationship between motor speed and motor current Relationship between motor speed and motor current Relationship between motor speed and motor current Condensation prevention operation diagram of control unit Top view configuration diagram showing a conventional heat exchange ventilator

  According to a first aspect of the present invention, there is provided a heat exchange type ventilator, wherein an air supply fan having an air supply motor, an exhaust fan having an exhaust motor, and air supply from the outside to the room by the air supply fan. Indoor air and outdoor air at a position where the air supply air passage, the exhaust air passage through which air is blown out of the room by the exhaust fan, and the air supply air passage and the exhaust air passage intersect. In a heat exchange type ventilator comprising a heat exchange element for exchanging heat when ventilating, and a controller for controlling the operation and rotational speed of the air supply motor and exhaust motor, the heat flows through the exhaust motor. The controller further includes current detection means for measuring current, and the control unit stores an exhaust motor current value for outputting a predetermined air volume at a predetermined external static pressure of the exhaust motor at the start of operation, and the exhaust motor is determined in advance. Operation with air flow When the current operating current value of the exhaust motor becomes larger than a predetermined value compared with the stored operating current value, it is detected that clogging has occurred inside the heat exchange element. And a configuration for reducing the rotational speed of the air supply motor. As a result, it is detected that the heat exchange element has started freezing without attaching a temperature sensor, and in order to prevent freezing, the rotation speed of the supply motor is reduced to reduce the supply air volume, thereby freezing the heat exchange element. It is possible to continue the operation of supplying air and exhausting while preventing the progress, and to obtain the effect of melting the freezing of the heat exchange element by raising the exhaust temperature by excessive exhaust operation.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
About the heat exchange type | mold ventilation apparatus of the 1st Embodiment of this invention, an internal structure, an air supply ventilation path, and an exhaust ventilation path | route are demonstrated using FIG. As shown in FIG. 1, a heat exchange ventilator 1 includes an outside air suction port 2 and an indoor air exhaust port 3 on the side surface of a box-shaped main body, and an outside air supply port 4 and room air on the side surface facing this side surface. A suction port 5 is provided. The heat exchange ventilator 1 has a control unit 11 that controls the rotation speeds of the supply motor of the supply fan 9 and the exhaust motor of the exhaust fan 10.

  The heat exchange ventilator 1 draws fresh outdoor air (supply air) from the side outside air inlet 2 and passes through the heat exchange element section 6 inside the heat exchange ventilator 1 to supply outside air. An air supply / air supply path 7 that is supplied from the mouth 4 to the room is provided. On the other hand, the contaminated indoor air (exhaust air) is sucked in from the indoor air suction port 5 and has an exhaust air blowing path 8 that is exhausted from the indoor air exhaust port 3 to the outside through the heat exchange element section 6. At this time, the heat exchanging element section 6 supplies the heat quantity of the exhausted air to the supplied air, or supplies the heat quantity of the supplied air to the heat quantity of the exhausted air. have.

  Fresh outdoor air (supply air) introduced from the outside air inlet 2 and contaminated indoor air (exhaust air) introduced from the indoor air inlet 5 are an air supply fan 9 and an exhaust fan 10. In this way, the air flows through the air supply and exhaust passage 7 and the exhaust air passage 8, respectively. The heat exchange element unit 6 is disposed at a position where the supply air blowing path 7 and the exhaust ventilation path 8 intersect. An air cleaning filter 12 is disposed on each of the outdoor air suction side and the indoor air suction side of the heat exchange element section 6.

  In addition, a duct (not shown) can be connected to each of the outside air inlet 2, the indoor air outlet 3, the outside air inlet 4, and the room air inlet. The duct connected to the outside air inlet 2 and the room air outlet 3 is routed to the outer wall surface of the building and communicates with the outdoor air outside the building. The duct connected to the outside air supply port 4 and the indoor air suction port 5 communicates with the ceiling surface or wall surface of the living room and communicates with the room air.

  The control unit 11 controls the rotation speeds of the air supply motor of the air supply fan 9 and the exhaust motor of the exhaust air fan 10 to control the supply air amount and the exhaust air amount while maintaining a constant current, and the current flowing through the exhaust motor Current detecting means for measuring the current.

  Here, the characteristic part in the present embodiment, that is, the operation of the control unit 11 will be described.

  When the heat exchange ventilator 1 is activated, the control unit 11 controls the rotation speeds of the air supply motor and the exhaust motor so that the airflow output from the air supply fan 9 and the exhaust air fan 10 are equal. (Heat exchange air operation)

  Normally, when the operation is started in the construction state, the external static pressure due to the predetermined duct routing is applied to the heat exchange type ventilator, and the control unit 11 sets the rotation speed of the exhaust motor in order to output a predetermined air volume. The current value is controlled while checking. The control unit 11 stores in advance the relationship between the supply motor rotation speed and the supply motor current value for outputting the predetermined air volume, and the relationship between the exhaust motor rotation speed and the exhaust motor current value. FIG. 2 shows the relationship between the motor rotation speed and the motor current value for realizing the predetermined air volume. The control unit 11 realizes the set predetermined air volume by matching the relationship between the motor rotation speed and the motor current value. The control unit 11 stores an exhaust motor current value (a point of the initial value P in FIG. 2) that outputs a predetermined air volume at the initial stage of the operation, that is, in a state where the heat exchange element unit 6 is not frozen. . FIG. 2 shows the state of the control unit 11 from t1 to t2 in FIG.

  If the outside air temperature decreases during the heat exchange operation as during the time t2 to t3 in FIG. 5, dew condensation occurs from the exhaust air blowing path 8 side of the heat exchange element section 6. This is because the temperature of the indoor air (exhaust air) flowing through the exhaust air flow path 8 is lowered below the dew point by exchanging heat with the outside air (supply air) in the heat exchange element section 6, that is, the temperature saturation after heat exchange This is because it retains more water than the amount of water vapor. The moisture generated by the condensation freezes when the exhaust temperature after heat exchange falls below 0 ° C., causing clogging of the heat exchange element 6 and lowering the ventilation function.

  The control unit 11 is configured to maintain a predetermined ventilation air volume even when freezing occurs in the heat exchange element unit 6 and the freezing causes airflow resistance and pressure loss increases. The current value of the exhaust motor is increased so as to increase the rotational speed of the exhaust motor in accordance with the relationship of the current value (FIG. 3). If the operation is continued as it is, freezing further proceeds and a large amount of freezing occurs. The frozen condensed water starts to melt when the outside air temperature rises, and the condensed water overflows from the heat exchange type ventilator 1. The overflowing water has an adverse effect on the installation location and leads to unsafe occurrence such as poor insulation due to water leakage.

  In order to avoid such an event, when the current value I of the exhaust motor as shown in FIG. 3 exceeds a predetermined current value Ia, the control unit 11 causes freezing in the heat exchange element unit 6. As shown in the period from time t3 to t4 in FIG. 5, the rotation speed of the air supply motor is decreased so that the air supply airflow rate becomes smaller than the exhaust airflow rate (in FIG. 5, the ratio of the air supply airflow rate is Down to 0.3). As a result, the exhaust air flow rate becomes larger than the supply air flow rate, and the introduction air flow rate of the outside air at a low temperature decreases, so that the exhaust temperature after heat exchange becomes high. If the exhaust temperature rises, the generated freezing can be melted. In addition, since the amount of saturated water vapor in the exhaust air is increased, more moisture can be retained, and the risk of condensation is reduced. If the freezing of the heat exchange element is gradually eliminated, the clogging of the heat exchange element unit 6 is eliminated, so that the control unit 11 follows the relationship between the exhaust motor rotational speed and the exhaust motor current value as shown in FIG. The current value of the exhaust motor can be reduced, and the rotational speed of the exhaust motor that achieves a predetermined air volume is reduced. As a result, the current value of the exhaust motor returns to the initial value P. By returning the current value to the original value, the control unit 11 can return to the normal heat exchange air operation by returning the rotation speed of the supply air motor to return the supply air flow rate ratio from 0.3 to 1. In this way, it is possible to switch to the freeze prevention operation without the temperature sensor and return to the heat exchange air operation again. FIG. 5 illustrates this series of flows.

  Here, the predetermined current value Ia is maintained when the operation is continued at a predetermined indoor temperature and humidity (for example, a room temperature specified in JIS B 8628), and freezing that adversely affects the product occurs in the heat exchange element (increase in heat exchange element pressure loss). This is an experimentally obtained value of the motor current that realizes the predetermined air volume.

The ventilator according to the present invention is effective as a duct-type ventilator for the purpose of exchanging heat between outside air and room air, a duct-type air conditioner, and the like.

DESCRIPTION OF SYMBOLS 1 Heat exchange type ventilator 2 Outside air suction port 3 Indoor air exhaust port 4 Outside air supply port 5 Indoor air suction port 6 Heat exchange element part 7 Supply air ventilation path 8 Exhaust air supply path 9 Supply air blower 10 Exhaust air blower 11 Control Part 12 Air purifying filter 101 Ventilator body 102 Outdoor air supply port 103 Heat exchange element unit 104 Indoor air supply port 105 Indoor exhaust port 106 Outdoor exhaust port 107 Electric motor 108 Same shaft 109 Air supply fan 110 Exhaust fan

Claims (1)

An air supply fan equipped with an air supply motor;
An exhaust fan with an exhaust motor;
An air supply air passage that is blown indoors from the outside by the air supply fan;
An exhaust air blowing path for blowing air from the room to the outside by the exhaust fan;
A heat exchange element for exchanging heat when ventilating indoor air and outdoor air at a position where the supply air blowing path and the exhaust air blowing path intersect;
In a heat exchange type ventilator comprising a controller for controlling the operation and rotation speed of the air supply motor and the exhaust motor,
A current detection means for measuring a current flowing through the exhaust motor;
The control unit stores an exhaust motor current value for outputting a predetermined air volume at a predetermined external static pressure of the exhaust motor at the start of operation,
When the exhaust motor is continuously operated at a predetermined air volume, when the current operating current value of the exhaust motor becomes greater than a predetermined value compared with the stored operating current value, Detects clogging in the
A heat exchange type ventilator characterized in that the number of rotations of the air supply motor is reduced.

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