JPS6033210B2 - Ventilation fan for duct - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a ventilation fan for ducts, which does not depend on the condition of the duct piping at each site, and even when used in areas with strong outside winds, can always maintain the optimum ventilation amount according to the constant ventilation setting. The purpose is to provide a configuration that can be obtained.

The ventilation fan for the secondary duct has outlet 1 as shown in Figure 1.
A shutter 102 that opens by wind pressure is attached to the tip of 01, and has a static pressure-air volume characteristic curve as shown in FIG. 2, and the air volume gradually decreases as the static pressure increases. Therefore, the amount of air discharged depends on the condition of the duct piping at each site, so it was necessary to re-design the ventilation and re-select the model for each site. Even in that case, the types of ventilation fans for ducts are limited, so it was not possible to match the air volume exactly to the ventilation design. As a result, there were constant problems such as the amount of ventilation air coming out more than necessary, increasing the heating and cooling load, or the necessary amount of ventilation air not being obtained, resulting in insufficient ventilation. Additionally, in areas with strong outside air, the amount of ventilation air was sometimes completely insufficient. The present invention solves the above-mentioned conventional drawbacks, and embodiments thereof will be described below with reference to FIGS. 3 to 8.

In Figs. 3 to 7, 1 is a main body with a built-in electric motor 3 to which blades 2 are fixed for discharging wind; 4 is a hole provided on one side of the main body 1 for discharging wind to the outside of the main body 1; The attached discharge port 5 is a shutter that is attached to the tip of the discharge port 4 so as to be openable and closable, and is closed when the ventilation fan is stopped to prevent backflow of wind, and opened by wind pressure when the ventilation fan is in operation.

6 is a power supply, 7 is a control part, 8 is an outer frame of the control part 7, 9 is a speed controller for controlling the rotation of the electric motor 3, and the input terminal is connected to the source 6 via a switch (SW, ) 10. A motor 3 is connected to the output terminal.

Reference numeral 11 denotes a volume knob for speed adjustment of the speed controller 9, which is connected to an output shaft 13 of a geared motor 12 connected in parallel to the power supply 6.

14 is a clutch lever for turning on and off the clutch mechanism built in the guard motor 12;
The electromagnet 15 connected in parallel with is energized, and the leaf spring 16
When the motor is attracted to the electromagnet 15, the clutch mechanism is engaged and rotational force is transmitted to the output shaft 13 of the guard motor 12.

Reference numeral 17 denotes a coil spring for releasing the leaf spring 16 from the clutch lever 14 via the fulcrum 18 and disengaging the clutch mechanism when the electromagnet 15 is de-energized.

19 is a pin attached perpendicularly to the output shaft 13 of the geared motor 12, and when the volume shaft 11 of the speed controller 9 is rotated by the geared motor 12 to the maximum position, the pin 19 is connected in series with the geared motor 12. This is for turning off the power to the guard motor 12 by pressing the micro switch (SW2) 20 connected to the motor.

21 is a coil spring for returning the volume shaft 11 of the speed controller 9 to the minimum position when the clutch mechanism of the geared motor 12 is disengaged and the output shaft 13 becomes freely rotatable.

Reference numeral 22 denotes a microswitch (SW3) that is attached to a position where it is activated when the shutter 5 opens and closes, and is pressed by the shutter when the shutter 5 opens to cut off the power to the geared motor 12. SW2) is connected in series with 20.

In the above structure, when the switch (SW, ) 10 is turned on, the geared motor 12 and the electromagnet 1 are passed through the speed controller 9, the microswitches 20 and 21 which are in the closed state.
5 is energized.

When the electromagnet 15 is energized, the leaf spring 16 is attracted to the electromagnet 15.

The leaf spring 16 pushes the clutch lever 14 and
The rotational force is transmitted to the output shaft 13 of the motor 12, and the volume shaft 11 of the speed controller 9 is rotated from the minimum position to the maximum position. Correspondingly, the rotation of the electric motor 3 increases, and the amount of air discharged from the discharge port 4 by the blades 2 increases. Therefore, the shutter 5 gradually increases its opening angle. Then, when the opening angle becomes constant, that is, the air volume becomes constant, the shutter 5 pushes the microswitch 22 to turn off the power to the guard motor 12. In this case, electromagnet 15
is energized, the clutch mechanism remains in the engaged state, and the output shaft 13 cannot rotate freely due to the static friction force of the reduction gear and stops at that position, so the speed controller 9
The volume shaft 11 also stops at that position and continues to discharge a constant amount of air. Next, when the switch 10 is turned off, the power to the speed controller 9, guard motor 12, and electromagnet 15 is cut off.

When the electromagnet 15 is de-energized, the leaf spring 15 moves to the fulcrum 18.
It is separated from the clutch lever 14 by a coil spring 17 attached through the clutch lever 14. Therefore, the clutch mechanism is turned off, the output shaft 13 of the geared motor 2 becomes rotatable, and the volume shaft 11 connected to the output shaft 13 is returned to its minimum position by the force of the coil spring 21. Next, if a static pressure exceeding the capacity is applied to the duct ventilation fan according to the present invention, the shutter 5 will not reach a certain opening angle and the microswitch 22 will not turn off.

Therefore, the guard motor 12 continues to rotate, and the volume shaft 11 of the speed controller 9 rotates to the maximum position. Then, the pin 19 attached to the output shaft 13 pushes the microswitch 20 to cut off the power to the guarded motor 12, thereby preventing damage to the speed controller 9 and the guarded motor 12. Even in this case, the power to the electromagnet 15 is not cut off, so the output shaft 13 stops at that position, the volume shaft maintains the maximum position, and the duct ventilation fan according to the present invention continues to operate at its maximum capacity. FIG. 8 shows an example of the static pressure vs. air volume characteristic of the duct ventilation fan according to the present invention.

In the figure, Q^ is the design air volume of this duct ventilation fan, and even if the static pressure increases to PB due to the condition of the duct piping, etc., the design air volume Q^ is always maintained. Pc indicates the static limit pressure of this duct ventilation fan. Thus, according to the present invention,
Detects insufficient exhaust air volume depending on the opening angle of the shutter,
It is not affected by the condition of the duct pipes at each site, and even when used in areas with strong outside winds, the optimal ventilation amount can always be obtained in accordance with the ventilation design.

This eliminates the need for ventilation designs or model selection tailored to each site, and as long as the applicable static pressure is within the applicable static pressure range, no matter what type of duct piping is used at the site, no matter where the outside wind is blowing, it can be used. Regardless of the model, the same model can be used, and the same optimal ventilation amount can be obtained as per the ventilation design. Therefore, there is no need to increase the cooling/heating load due to excessive ventilation air volume, and conversely, there is no possibility that the required ventilation volume cannot be obtained and insufficient ventilation occurs. This exhibits the effects described above.

[Brief explanation of the drawing]

Fig. 1 shows a conventional duct ventilation fan, Fig. 2 shows a static pressure-airflow curve of a conventional example, Fig. 3 shows a duct ventilation fan according to an embodiment of the present invention, and Fig. 4 shows the area within the circle in Fig. 3. An enlarged view, Figure 5 is a diagram of the control part of the ventilation fan for the same duct, and Figure 6 is the X in Figure 5.
7 is a circuit diagram of the ventilation fan for the same duct, and FIG. 8 is a static pressure-airflow curve of the ventilation fan for the same duct. 1...Body, 2...Blade, 3...
...Electric motor, 4...Discharge port-, 5...Shutter, 9...
...Speed controller, 10...Switch (SW,). Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 7 Figure 6 Figure 8

Claims (1)

[Claims] 1. A main body containing a built-in electric motor to which blades are fixed, a discharge port for discharging wind, a shutter provided at the discharge port, and a switch operated by the movement of the shutter;
and a speed controller that controls the rotation of the electric motor, and is configured to sense the air volume based on the open state of the shutter, operate the switch, and control the operation with the speed controller. Ventilation fan for duct.