JPS63123935A - Ventilation fan - Google Patents

Abstract

PURPOSE:To correct a motor output in response to a ventilation resistance variation factor and to get a superior ventilation characteristic by a method wherein a motor output of a blower device is controlled in such a way as a desired amount of ventilation air can be attained in response to an air speed sensing signal of an air speed sensor arranged in an air passage. CONSTITUTION:A ventilation fan device is composed of a main body 1 for discharging air through a discharging duct 8 under rotation of an air blowing vane 4 and a control circuit 12 for controlling an output of a driving motor 5 for the blowing van 4 in such a way as a desired amount of ventilation air in response to an air speed sensing signal of an air speed sensor 11 arranged in the discharging duct 8. With an arrangement as above, ventilation air amount varying in response to a ventilation resistance varying factor such as a housing structure or external weather condition is detected by an air speed sensing signal of an air speed sensor 11 arranged in the discharging duct 8 of the main body 1 and then the control circuit 12 may control an output of a motor 5 in such a way as it produces a desired amount of ventilation air. Therefore, if is possible to correct the motor output in response to a ventilation resistance varying factor and to get always stable ventilation performance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a ventilation fan that controls ventilation air volume.

(Prior Art) Conventionally, a ventilation fan has a configuration in which a ventilation fan includes a ventilation device consisting of ventilation blades and a motor that rotates the blades, etc. is communicated with the outside through an exhaust duct or the like. In conventional ventilation fans, the motor is operated at a constant output to rotate the blower blades, thereby discharging indoor air to the outdoors.

(Problem to be Solved by the Invention) By the way, ventilation resistance, which is the resistance to the air blowing device of a ventilation fan, depends on the structure of the house, such as the degree of sealing of the room, the length of the exhaust duct, and the direction and speed of the wind outside. Although the situation changes depending on external weather conditions, in the conventional ventilation fans mentioned above, since the output of the motor is constant, the ventilation air volume changes due to fluctuations in ventilation resistance, making it impossible to obtain optimal ventilation performance. there were.

The present invention has been made in view of the above circumstances, and its purpose is to modify the output of the motor according to ventilation resistance fluctuation factors such as the structure of the house and external weather conditions, thereby stabilizing good ventilation performance at all times. There are ventilation fans available.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a main body that includes a blower device including a blower blade and a motor that rotationally drives the blower blade, and discharges air through a ventilation passage by rotation of the blower blade. , a wind speed sensor provided in the ventilation path of the main body, and a control circuit that controls the output of the motor to obtain a predetermined ventilation air volume based on the wind speed detection signal from the wind speed sensor. .

(Function) The ventilation air volume changes depending on ventilation resistance fluctuation factors such as the house structure and external weather conditions, and this ventilation air volume is detected by the wind speed detection signal from the wind speed sensor installed in the ventilation path of the main unit. Based on this wind speed detection signal, the control circuit controls the output of the motor so that the ventilation air volume is a predetermined ventilation air volume. Therefore, the output of the motor is adjusted in accordance with the ventilation resistance variation factor, and good ventilation performance can always be stably obtained.

(Example) An example in which the present invention is applied to a range hood fan will be described below with reference to the drawings.

First, in FIG. 1, 1 is the main body, which is inside the hood 2 and has a fan casing 3. It is constructed by disposing an air blowing device 6 consisting of a sirocco fan 4 serving as an air blowing blade and a DC motor 5. In the hood 2, the lower opening is an intake port 2a, and a filter 7 is attached to the intake port 2a. Further, at the top of the hood 2, there is an exhaust casing 8 that communicates with the discharge port 3a of the fan casing 3.
An exhaust port 9 is formed on the rear surface of the exhaust casing 8. Such a main body 1 is disposed on a wall of a room, and in this case, the exhaust port 9 communicates with the outside through an exhaust duct 10. When the sirocco fan 4 is rotationally driven by the motor 5, indoor air is sucked into the fan casing 3 through the intake port 2a and the intake port 3b of the fan casing 3, as shown by arrow A in the figure. , and the discharge port 3a, inside the exhaust casing 8, and the exhaust port 9. It is exhausted to the outside through the exhaust duct 10.

Now, reference numeral 11 denotes a wind speed sensor, which is disposed inside the ventilation path, for example, the exhaust duct 8 in the main body 1, and outputs a wind speed detection signal according to the wind speed. On the other hand, 12 is a control circuit consisting of a microcomputer, and this is provided in the control box portion 2b on the back surface of the lower front plate of the hood 2. A wind speed detection signal from the wind speed sensor 11 is given to this control circuit 12. Further, 13 is a lamp as an abnormality alarm, which is connected to the control circuit 12.
The lighting is controlled by. 14 is a power switch.

Note that a shutter (not shown) is provided on the outdoor side of the exhaust duct 10.

Therefore, the ventilation air volume (air blowing capacity) of the air blower 6 when the sirocco fan rotates four times is determined by its static pressure and ventilation resistance (air blowing resistance), and the relationship between them is shown in Fig. 2. ing. In this Figure 2, the curve P! shows static pressure characteristics, and curves R1+R2 show different ventilation resistance characteristics. In this case, the ventilation air Q produced by the operation of the blower 6 is determined by the intersection of the static pressure characteristic and the ventilation resistance characteristic. Therefore, under the static pressure characteristic shown by curve P1, if the ventilation resistance characteristic is given by curve R1,
The ventilation wind uQ becomes the ventilation wind J2Q1 at the intersection of the curve Pi and the curve R1, and the ventilation resistance characteristic is the curve R2.
The ventilation air 1uQ is given by curve Pl and curve R
The ventilation air volume at the intersection with 2 is Q2. As can be seen from this, when the ventilation resistance characteristic is kept constant, the ventilation wind WQ also increases or decreases as the static pressure increases or decreases.

The control circuit 12 calculates the current air volume based on the wind speed detection signal from the wind speed sensor 11, and sets the calculated air volume to a predetermined ventilation air volume (optimum ventilation air Em) Qn. The output of the motor 5 is controlled so that

For example, when the motor 5 is currently operating at the output it provides, if the room is highly sealed, the air resistance in the exhaust duct 10 is large, or there is strong outdoor wind. Sometimes the ventilation resistance becomes large, as shown by curve R3 in FIG. In this case, the ventilation air volume is set to Q' which is smaller than the predetermined ventilation air mQo. Then,
The ventilation air volume Q' at this point in time is calculated and determined by the control circuit 12 based on the wind speed detection signal from the wind speed sensor 11. And the control circuit 12 controls the ventilation air ff1Q'
and the prescribed ventilation wind mQ.

The motor 5 is controlled to increase its output, and the static pressure characteristic is determined from the static pressure characteristic (curve P2) corresponding to the ventilation air volume Q' at this point in time by the curve shown in FIG. 3. P3
The ventilation air volume Q is increased to match the predetermined ventilation air m Q g. In addition, as in the case where the shutter (not shown) does not open, the predetermined ventilation air QQ
If the output of the motor 5 exceeds the specified value without obtaining o, the lamp 13 is turned on to indicate an abnormality.

Also, if the outdoor wind is blowing in a direction that creates negative pressure indoors, or if the density of the room is low, the ventilation resistance will be small, as shown by curve R4 in Figure 4. Become. In this case, the ventilation air volume is set to Q' which is larger than the predetermined ventilation air QQo. Therefore, the ventilation wind ff1Q at this point
' is calculated and determined by the control circuit 12 based on the wind speed detection signal from the wind speed sensor 11. Then, the control circuit 12 compares and determines the ventilation air volume Q'' with a predetermined ventilation air volume Qo, controls the motor 5 to lower its output, and thereby adjusts the static pressure characteristic to the ventilation air volume QQ' at this point. From the corresponding static pressure characteristic (curve Pa), curve P5 in FIG.
As shown in , the ventilation air mQ is decreased to match the predetermined ventilation air volume Qo.

In the embodiment described above, the ventilation air volume is calculated based on the wind speed detection signal from the wind speed sensor 11, and the output of the motor 5 is controlled based on the comparison result between the ventilation air volume and the predetermined ventilation air Qg. However, a predetermined ventilation air volume may be obtained by controlling the output of the motor 5 based on a comparison result between the wind speed detected by the wind speed detection signal from the wind speed sensor 11 and a predetermined wind speed. Also, as an abnormality alarm,
A buzzer may be used instead of the lamp 13.

The pond water invention is not limited to the above embodiments,
For example, it can be applied to a ceiling ventilation fan in addition to a range hood fan, and can be modified in various ways without departing from the scope of the invention.

[Effects of the Invention] As is clear from the above description, the present invention provides a wind speed sensor in the ventilation path of the main body, and adjusts the output of the motor to obtain a predetermined ventilation air volume based on the wind speed detection signal from the wind speed sensor. Since a control circuit is provided, the output of the motor can be adjusted according to ventilation resistance fluctuation factors such as the structure of the house and external weather conditions, making it possible to consistently obtain good ventilation performance. be effective.

4 Simplified explanation 1) The first explanatory drawings show one embodiment of the present invention, in which Fig. 1 is an overall longitudinal cross-sectional side view, Fig. 2 is a diagram showing the relationship between static pressure, ventilation resistance, and ventilation air volume. 3 and 4 are diagrams showing the relationships among static pressure, air loss resistance, and ventilation air, respectively, to explain the functions.

In the diagram, 1 is the main body, 4 is the sirocco fan (blow blade), and 5
1 is a motor, 6 is a blower, 11 is a wind speed sensor, 12 is a control circuit, and 13 is a lamp.

Applicant: Toshiba Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] 1. A main body that has a blower device consisting of a blower blade and a motor that rotationally drives the blower blade, and discharges air through a ventilation passage by rotation of the blower blade; a wind speed sensor provided in the ventilation passage of this main body; A ventilation fan comprising: a control circuit that controls the output of the motor to obtain a predetermined ventilation air volume based on a wind speed detection signal from a sensor.