JP4830587B2 - Ventilation system - Google Patents

Description

The present invention relates to ventilation systems that implement the evacuation of constant air volume regardless of the length of the pipe length.

  In recent years, ventilators equipped with a DC motor capable of controlling the number of revolutions capable of fine air volume control have been developed. Since such a ventilator is affected by the length of the duct and the outside air pressure, the air volume fluctuates, so a method for controlling the air volume to a constant air volume, for example, as shown in Patent Documents 1 to 3, has been proposed. Yes.

  In Patent Document 1, the entire ventilation air volume is set by the exhaust side of the blower. A pressure sensor for detecting the wind pressure is provided on the exhaust side of the blower, and the air blower is controlled by the control circuit from the pressure detected by the pressure sensor. It is something to control.

  The thing shown in patent document 2 is equipped with the pressure sensor which detects the pressure difference of the upstream of an intake air path, and a downstream side that the thing shown in patent document 1 is difficult to respond | correspond to size reduction of a pressure sensor or a control circuit. The blower is controlled so that the pressure difference detected by the pressure sensor matches a preset target value, and a mounting surface is formed on a part of the intake structure, and the pressure difference is detected on the mounting surface. And a control box containing a control circuit and a pressure sensor is attached to the mounting surface.

  In addition, what is disclosed in Patent Document 3 is an apparatus in which a control circuit measures a characteristic value of a DC motor without using a sensor to estimate an air volume, thereby controlling the DC motor to ensure a predetermined air volume. is there.

JP-A-1-239330 Japanese Patent No. 3399140 Japanese Patent Laid-Open No. 2003-143887

  In the pressure sensor described above, the pressure sensor is expensive, and there is a problem that the mounting structure of the pressure sensor is complicated.

  In addition, the method of using the DC motor characteristic value for air volume estimation is to obtain the motor characteristic value by experiment and store the data in a storage device (ROM) such as a microcomputer. There was a problem that required time and therefore the development period was long.

  An object of the present invention is to solve the above problems.

In order to achieve the above object, a ventilator according to the present invention is connected to a casing having an air inlet and an air outlet, a fan motor equipped with a fan accommodated in the casing, a control device for driving the fan motor, and the air outlet. The control device comprises speed control means for controlling the rotational speed of the fan motor, and a self-heating type thermistor installed outside the first small hole provided in the exhaust duct, The control device controls the number of rotations of the fan motor so that the air speed of the air discharged from the first small hole detected by the self-heating type thermistor becomes a predetermined value, thereby keeping the air volume discharged from the exhaust port constant. a ventilation system to keep the self-heating type thermistor is retract and the box having a second small hole in the bottom, near the second small hole in the first small holes And made to communicate with arranged, the diameter of the first small holes are provided by increasing relative to the diameter of the second small holes, to provide a ventilation system with improved workability on site.

ADVANTAGE OF THE INVENTION According to this invention, the ventilation system which improved workability | operativity in the field with a simple structure can be provided.

External view of ventilation apparatus of Embodiment 1 of the present invention The figure which shows the attachment state of the ventilation device Sectional plan view showing the structure Diagram showing the electrical configuration Diagram showing the relationship between thermistor wind speed and thermistor voltage The figure which shows the voltage which is remembered in the memory of the same CPU Flow chart showing operation of air volume control of the control device The figure which shows the structure of Embodiment 2 of this invention The figure which shows the structure of Embodiment 3 of this invention

According to the first aspect of the present invention, a casing having an intake port and an exhaust port, a fan motor equipped with a fan housed in the casing, a control device for driving the fan motor, and an exhaust duct connected to the exhaust port The control device comprises speed control means for controlling the rotational speed of the fan motor, and a self-heating type thermistor installed outside the first small hole provided in the exhaust duct. Ventilation that keeps the air volume discharged from the exhaust port constant by controlling the number of revolutions of the fan motor so that the wind speed of the air discharged from the first small hole detected by the self-heating thermistor becomes a predetermined value. a system, the self-heating type thermistor second to retract and the box having a small hole in the bottom, is communicated adjacent to and communicating said second small hole in the first small holes Arrangement, and the diameter of the first small holes are ventilation system, characterized in that provided by increasing relative to the diameter of the second small holes.

This improves the workability of the ventilation system construction that can accurately control the air volume .

The invention according to claim 2 of the present invention is the ventilator according to claim 1, wherein the center of the second small hole of the box containing the self-heating type thermistor is the center of the first small hole of the exhaust duct . The box is attached to the exhaust duct so as to match.

  As a result, the wind speed can be regulated by a small hole in the box, and the small hole in the exhaust duct only needs to be opened larger, thereby improving the workability on site.

According to a third aspect of the present invention, in the ventilator according to any one of the first to second aspects, the control device includes a temperature correction thermistor, and the temperature correction thermistor detects a wind speed value detected by the self-heating thermistor. It is characterized by correcting at the ambient temperature.

According to a fourth aspect of the present invention, in the ventilation system according to any one of the first to third aspects, the control device includes a temperature correction thermistor, and the ambient temperature where the temperature correction thermistor detects the wind speed value detected by the self-heating thermistor. It is characterized by correcting with temperature.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is an external view of a ventilation device and a ventilation system.

  FIG. 1 shows a state (ventilation system) in which a ventilator 1 is connected to a plurality of intake boxes 2 by respective intake ducts 3 and an exhaust duct 4 is connected.

  The control box 5 is provided outside the ventilation device 1 and houses a control device described later.

  FIG. 2 is a view showing a state where the ventilation device and the ventilation system of FIG. 1 are attached to the ceiling of a building. As shown in FIG. 2, the ventilation device 1 and the intake box 2 are attached to the beam 101 in a suspended state. The lower end of the intake box 2 passes through the ceiling 102 and is covered with the intake grill 6. The tip of the exhaust duct 4 passes through the wall 103 and is covered with the exhaust grill 7.

  When the fan 9 attached to the fan motor 8 rotates, an air flow is generated in the intake grill 6, the intake box 2, the intake duct 3, the fan 9, the exhaust duct 4, and the exhaust grill 7 as indicated by arrows, and the air in the building is It is discharged outdoors.

  Fig.3 (a) is a figure which shows the structure of a ventilator, and is sectional drawing which looked at the ventilator of FIG. 2 from the lower surface (AB view).

  The casing 10 is provided with three intake ports 11 and exhaust ports 12. A guide vane 13 is provided around the fan 9, and air sucked from the air inlet 11 by the rotation of the fan 9 in the direction of the arrow is discharged from the air outlet 12. The control device 14 is accommodated in the control box 5.

  FIG. 3B is an enlarged view of a portion indicated by C in FIG.

  A small hole 10a is provided in the casing 10 with which the end portion on the exhaust side of the guide vane 13 abuts, and the negative air is mounted on the control device 14 in the airflow at the wind speed V discharged from the small hole and flowing out from the hole 5a of the casing 10. A self-heating type thermistor 15 having temperature characteristics is placed.

  Here, the wind speed V has a correlation with the exhaust air volume Q and has a substantially proportional relationship.

  The correction thermistor 16 is also mounted on the control device 14.

  FIG. 4 is a diagram showing an electrical configuration of the ventilation device.

  The control device 14 connected to the fan motor 8 energizes the resistors 17 and 18 connected to the self-heating thermistor 15 and the temperature correction thermistor 16 with the power source 19, and sets the two voltages across the two thermistors. A / D converters 20 and 21 respectively convert the digital values to input to a CPU (central processing unit such as a microcomputer) 22. A speed control means 23 is connected as an output of the CPU 22. The switch 24 is connected.

  Here, the speed control means is, for example, a pulse width modulation (PWM) type speed adjusting device.

  FIG. 5 is a diagram showing the relationship between the wind speed V and the thermistor voltage E detected by the self-heating type thermistor.

  The self-heating type thermistor 15 that is self-heating has the lowest resistance value in the state of zero wind speed, and the voltage E is the lowest value. It has the following characteristics.

  Further, the resistance value increases when the temperature of the cooled wind is low, and conversely, the resistance value decreases when the temperature of the wind is low.

  FIG. 6 is a diagram showing the air volume setting stored in the internal memory (ROM) of the CPU 22 and the value (predetermined value) of the voltage E described in FIG.

  For example, when the air volume setting switch 24 is set to be weak and the ambient temperature is 25 ° C., the predetermined value is E1.

  Next, the air volume control operation of the control device 14 will be described with reference to FIGS.

  In S (step) 1, the control device 14 reads the setting value of the air volume setting switch 24, for example, weak (V1) in FIG. 6, and then reads the ambient temperature detected by the correction thermistor 16, for example, 25 ° C. in S2.

  Next, in S3, the predetermined value E1 described in FIG. 6 is selected.

  Next, in S4, the fan motor 8 is accelerated.

  Next, in S5, the voltage E detected by the self-heating thermistor 15 is compared with a predetermined value E1, and if E> E1, the fan motor 8 is decelerated (S6). Next, if E <E1, the fan motor 8 is decelerated. Speed up.

  The above operations are performed in the form of a CPU program in which the RAM and ROM in the CPU 22 work together.

  By repeating such an operation, the wind speed V of the self-heating type thermistor 15 is kept constant.

  As described above, since the wind speed V and the exhaust air volume Q of the ventilator are correlated, the exhaust air volume Q is kept constant by keeping the wind speed V constant.

  As described above, the wind speed of a minute air quantity discharged from the small hole detected by the self-heating thermistor installed outside the circular small hole having a diameter of about 1 mm, for example, provided in the portion constituting the exhaust passage of the casing. By controlling the number of rotations of the fan motor so as to be a predetermined value, the amount of exhaust air discharged from the exhaust port can be kept constant.

(Embodiment 2)
Since this embodiment is the same except for FIG. 3 in FIGS. 1 to 7 described in the first embodiment, FIG. 8 will be described instead of FIG. The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  8A is a cross-sectional plan view showing the same structure as FIG. 3A, and FIG. 8B is an enlarged view of D in FIG. 8A.

  Since 9, 10, 11, 12, and 13 having the same reference numerals as those in FIG.

  As shown in FIG. 8B, a small hole 12 a is provided on the side surface of the exhaust port 12.

  A static pressure is generated on the wall surface of the exhaust port 12 in a direction perpendicular to the direction of the exhaust flow and in accordance with the value of the exhaust air volume Q (proportional to the square root of Q). V) It is discharged from the hole 5a and discharged from the hole 5b of the control box 5.

  The self-heating type thermistor 15 is placed in the air of the discharged wind speed V, and as described in the operation of the first embodiment, the rotational speed of the fan motor 8 is controlled so that the wind speed V becomes constant. Thus, the exhaust air volume Q can be made constant.

(Embodiment 3)
The present embodiment is an embodiment implemented in a state in which an exhaust duct is mounted on the ventilation device, that is, in the state of the ventilation system. Since this embodiment is the same except for FIG. 3 in FIGS. 1 to 7 described in the first embodiment, FIG. 9 that replaces FIG. 3 will be described. The same parts as those in the first or second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  9A is a cross-sectional plan view showing the same structure as FIG. 3A, FIG. 9B is an enlarged view of D in FIG. 9A, and FIG. 9C is a perspective view thereof. is there.

  Since 9, 10, 11, 12, and 13 having the same reference numerals as those in FIG.

  Holes 4a, 4b and 4c are provided in the exhaust duct 4 attached to the exhaust port 12 at the construction site, and the box 25 is fixed with screws 4d and 4e.

  A self-heating type thermistor 15 is attached to the substrate 15 a in the box 25, and a lead wire 15 b is connected to the control device 14 in the control box 5.

  A small hole 25 a is provided at the bottom of the box 25 below the self-heating thermistor 15, and a hole 25 b is provided at the other side of the box 25.

  The small holes 25a coincide with the holes 4a of the exhaust duct 4 at the respective centers. The diameter of the hole 4a is larger than that of the small hole 25a.

  As described in the second embodiment, a static pressure is generated on the wall surface of the exhaust duct 4 in a direction perpendicular to the direction of the exhaust flow and in accordance with the value of the exhaust air volume Q, and air having a wind speed V proportional to the static pressure. (V in the drawing) is discharged from the small hole 25a and discharged from the hole 25b of the box 25.

  The self-heating type thermistor 15 is placed in the air of the discharged wind speed V, and as described in the operation of the first embodiment, the rotational speed of the fan motor 8 is controlled so that the wind speed V becomes constant. Thus, the exhaust air volume Q can be made constant.

  In the present embodiment, the exhaust air volume Q is in a laminar flow state, and a stable static pressure is generated without being affected by dynamic pressure. Therefore, the wind speed V is also stable, and the exhaust air volume can be controlled with high accuracy.

  Moreover, since the wind speed V is defined by the diameter of the small hole 25a of the box 25 by designating in the construction instruction so that the diameter of the hole 4a is larger than that of the small hole 25a, Fine adjustments can be made, and on-site workability is improved.

  Since the ventilator of the present invention can supply a stable exhaust amount regardless of the pipe length and the external air pressure, it can be applied to a ventilator of a simultaneous supply / exhaust type ventilator.

DESCRIPTION OF SYMBOLS 1 Ventilation device 4 Exhaust duct 4a Hole 5 Control box 5a Hole 5b Hole 8 Fan motor 9 Fan 10 Casing 10a Small hole 11 Intake port 12 Exhaust port 12a Small hole 14 Control device 15 Self-heating type thermistor 16 Correction thermistor 23 Speed control means 25 box 25a small hole

Claims (4)

A casing having an air inlet and an air outlet, a fan motor equipped with a fan housed in the casing, a control device for driving the fan motor, and an exhaust duct connected to the exhaust port, the control device being the fan motor And a self-heating thermistor installed outside the first small hole provided in the exhaust duct, and the control device detects the first temperature detected by the self-heating thermistor. A ventilation system that keeps the amount of air discharged from the exhaust port constant by controlling the rotational speed of the fan motor so that the air speed of air discharged from the small hole of the air hole becomes a predetermined value. yield was placed in a box provided with a second small hole in the bottom, said second small hole adjacent to and made to communicate with the first small holes are arranged, the diameter of the first small holes Ventilation system provided by increasing relative to the diameter of the second small holes.
Ventilation system according to claim 1, wherein the box attached to the exhaust duct so that the center of the second small holes of the box housing the self-heating type thermistor matches the center of the first small holes of the exhaust duct. The ventilation device according to any one of claims 1 to 2 , wherein the control device includes a temperature correction thermistor, and corrects a wind speed value detected by the self-heating thermistor with an ambient temperature detected by the temperature correction thermistor. The ventilation system according to any one of claims 1 to 3 , wherein the control device includes a temperature correction thermistor, and corrects a wind speed value detected by the self-heating thermistor with an ambient temperature detected by the temperature correction thermistor.

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