JPS63207935A - Automatic operation device for air feed fan - Google Patents

Abstract

PURPOSE:To maintain the pressure differential between the indoor and the outdoor so as to perform a stable and pleasant ventilation by disposing a sensing element which changes its electrical conductivity characteristics in accordance with the pressure differential between the indoor and the outdoor, and operating a feed air fan which changes its speed in accordance with the output signal from a micro computer. CONSTITUTION:When an air purge fan 2 is operated, a pressure differential is generated between the indoor 10 of a house 1 and the outdoor 9. Then, a pressure differential is generated between an indoor side sensing opening 6 and the outdoor side sensing opening 8, which causes electrical conductivity characteristics of a sensing element 7 to similarly change, and the change of ON time of it is inputted to a micro computer. When the ON time becomes greater than a certain limit, an operation command is issued from the micro computer to start the electrical supply, and the speed of a feed air fan 15 is progressively increased and maintained within an allowable range for a certain continuity time. When the ON time begins decreasing, the continuity time is reduced to progessively reduce the speed of the feed air fan 4, and a certain continuity time is maintained with the fan speed in an allowable range. When the ON time becomes lower than a certain limit, the feed air fan 4 is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a ventilation system that can maintain an appropriate pressure difference between indoors and outdoors in order to perform effective ventilation.

BACKGROUND OF THE INVENTION In recent years, buildings have become taller in order to make effective use of land, and houses are no exception, and apartment complexes are also becoming taller. As buildings become taller, the influence of outside wind becomes greater, and in order to maintain the effectiveness of heating and cooling, houses must be extremely airtight.

For this reason, conventional ventilation systems for houses had a configuration as shown in Figure 3. That is, the house 101 is provided with an exhaust fan 102 at the exhaust port 103 and an air supply fan 104 at the air supply port 105, and when the exhaust fan 102 is operated, the supply air fan 104 is operated in conjunction with the exhaust fan 102 to increase the exhaust volume. Accordingly, the living room was ventilated by taking in air from the air supply ports 1 and 6.

Further, the control circuit in this type of air supply fan 104 is as follows:
The configuration was as shown in FIG. That is, when the pressure difference between the indoor and outdoor areas exceeds a predetermined value by the differential pressure switch 106, the contact of the differential pressure switch 106 is turned on to drive the air supply fan 104, and when the pressure difference falls below the predetermined value, The contact of the differential pressure switch 106 is turned off and the air supply valve 77 is turned off.
104 was to be stopped.

Problems to be Solved by the Invention In such a conventional configuration, when the exhaust fan 102 is operated and the pressure difference between the indoor and outdoor areas exceeds a predetermined value,
Turn on the contact of the differential pressure switch 106 to turn on the air supply fan 104
However, when the air supply fan 10 is driven, the pressure difference between indoor and outdoor becomes less than a predetermined value in a short time, and the air supply fan 10 is driven.
4 stops.

However, since exhaust fan 1o2 continues to operate,
There was a problem in that the pressure difference soon exceeded a predetermined value and the air supply fan was driven again, repeating driving and stopping in a short period of time.

The present invention solves these problems by controlling the operation of the air supply fan so that the pressure difference between indoors and outdoors is maintained within a permissible range, thereby providing air supply for stable and comfortable ventilation. The present invention provides an automatic fan operation device.

Means for Solving the Problem In order to solve this problem, the present invention has a sensing element whose conductive characteristics change in response to the pressure difference between indoors and outdoors, and which detects the change in the conductive characteristics of this sensing element. a detection circuit that outputs a detection signal that changes according to the detection signal; and a detection circuit that starts generating an output signal when the output of the detection signal exceeds a predetermined value, and generates an output signal when the output of the detection signal decreases. a microcomputer that reduces the pressure difference between the indoor and outdoor areas within an allowable range, and stops generating an output signal when the output of the detection signal exceeds a predetermined value; This system constitutes an automatic operation device for an air supply fan, which is equipped with a drive circuit that changes the rotational speed and operates the air supply fan.

Operation With this configuration, when the output of the detection signal of the detection circuit due to a change in the conductive characteristics of the detection element exceeds a predetermined value, the rotation of the air supply fan 1 is started, and the rotation speed is gradually increased. ,
The rotation speed of the air supply fan is maintained at a speed that keeps the pressure difference between indoors and outdoors within an allowable range, and the rotation of the air supply fan is stopped when the output falls below a predetermined value.

In this way, the pressure difference between indoors and outdoors can be maintained near the permissible value, and the air supply fan can be automatically operated for stable ventilation.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, a house 1 has an exhaust fan 2 at an exhaust port 3, an air supply fan 4 at an air supply port 5, an outdoor detection port 8, and an indoor detection port 6, and is sensitive to the pressure difference between indoors 1o and outdoors 9. A sensing element 7 whose conductive properties change is provided. The detection element 7 is an astable multivibrator circuit 12 connected to a microcomputer 14 via a waveform shaping circuit 13.
It is arranged as a component of Then, an operation command is sent from the output section of the micro combinator 14 to the triac 16 connected between the air supply fans 4 to change the conduction time and control the number of revolutions of the air supply fan 60.

The operation of the air supply fan automatic operation device having the above configuration will be described below.

When the exhaust fan 2 provided at the exhaust port 3 of the house 1 is operated, a pressure difference is generated between the indoor 10 and the outdoor 9 of the house 1. Then, at the outdoor detection port 8 and the indoor detection port 6, the indoor
A pressure difference occurs between 0 and the outside 9, and the conductive characteristics of the sensing element 7 change accordingly, and this change in resistance value is changed to the off time of the square wave by the astable multivibrator circuit 12, and this square wave The wave passes through the waveform shaping circuit 13 and is input into the microcomputer 14 as a change in on time. When this ON time exceeds a predetermined value (for example, an ON time corresponding to -3 mmAq), an operation command is issued from the microcomputer 14 to the triac 16 to start conduction and gradually increase the number of rotations of the air supply fan 160. ,
Within the allowable range (for example -2wAq to -3ramAq
The conduction time of the command issued to the triac 16 is maintained at the time corresponding to Also, if the on time starts to decrease, the microcomputer 1
An operating command is issued to the triac 16 from 4 to reduce the conduction time to gradually lower the rotational speed of the air supply fan 4, and the conduction time issued to the triac 16 is maintained within a permissible value. Further, the on-time is stopped when it becomes less than a predetermined value (for example, -2aA (on-time corresponding to i)).

As described above, according to this embodiment, the astable multivibrator circuit 12 which is a detection circuit and the microcomputer 1
4 controls the operation of the air supply fan, indoor 10 and outdoor 9.
By keeping the pressure difference at a nearly constant value that allows for effective ventilation, it is possible to prevent repeated activation and stopping in a short period of time, and automatic ventilation operation with excellent stability and comfort can be achieved.

In the embodiment, the pressure difference is input to the microcomputer 14 by converting it into a square wave on time via the astable multivibrator 12 and the waveform shaping circuit 13, or there is no limitation on the pressure difference conversion method. Needless to say. Further, although the air supply fan 4 is an AC motor and the triac 16 is used to control the rotation speed by phase control, it goes without saying that there is no limitation to the rotation speed control method. Furthermore, although the air supply fan 4 has been described using an AC motor, it goes without saying that there is no limit to the type of motor whose rotation speed can be controlled.

Effects of the Invention As is clear from the above description of the embodiments, the present invention uses an air supply fan, a pressure difference detection element, a microcomputer, etc. to maintain the pressure difference between indoors and outdoors at a value that allows effective ventilation. This makes it possible to maintain stable and comfortable ventilation, which has an extremely large effect.

[Brief explanation of the drawing]

FIG. 1 is a control circuit diagram of an automatic operation device for a supply air fan according to an embodiment of the present invention, FIG. 2 is a configuration diagram of an automatic operation device for the same supply air fan, and FIG. A configuration diagram of the operating device, and FIG. 4 is a control circuit diagram thereof. 4...Air supply fan, 7...Detection element,
12... Astable multivibrator circuit, 14
・・・・・・Microcomputer, 16・・・・・・
Triac.

Claims (1)

[Claims] A detection circuit includes a detection element whose conductive properties change in response to a pressure difference between indoors and outdoors, and outputs a detection signal that changes according to the change in the conductive properties of the detection element, and the output of the detection signal is set to a predetermined value. The generation of an output signal is started when the value of The fan is equipped with a microcomputer that stops generating an output signal when the output of the fan becomes less than a predetermined value, and a drive circuit that changes the rotation speed and operates the air supply fan based on the output signal of the microcomputer. Automatic operation device for air supply fans.