TECHNICAL FIELD

Engineering related to automatic ventilation control system

BACKGROUND OF THE INVENTION

Residential premises or offices nowadays are mostly air-conditioned but lack ventilation system. As a consequence, the air quality within such premises is deteriorated i.e. having more carbon dioxide than the outside air, affecting the health of the resident, e.g. by causing lethargy, drowsiness, apathy and inefficiency at work.

In the case where there is a ventilation system, the ventilation fan often operates around the clock and inevitably venting the cooled air outdoors. In turn, the air conditioner will require extra energy for normal operation, resulting in energy overconsumption.

As a result, there have been several efforts to solve such problem by providing the ventilation system which includes a ventilation control unit, wherein said system detects carbon dioxide. When carbon dioxide exceeds the determined value, said control unit commands the ventilation fan to operate without controlling its rotation speed. Such ventilation system will cause the temperature within the premise to rise rapidly because the ventilation fan always operates at its maximum rate despite the different carbon dioxide concentration levels.

Therefore, such system can affect the operation of the air conditioner such as by causing the air conditioner to overwork as well as to consume more energy.

Based on the above, the conventional ventilation system still has operational limitations, thus there remains the need for a developed or improved ventilation system capable of solving such limitations.

SUMMARY OF THE INVENTION

The present invention relates to an automatic ventilation control system comprising: a ventilation fan mounted in a ventilation opening; an inlet shutter which is openable and closable, installed at an air inlet; a gas sensor which includes a carbon dioxide sensor and/or an oxygen sensor for detecting the concentration of carbon dioxide and/or oxygen and a control unit which receives the signal from the carbon dioxide sensor and/or the oxygen sensor for controlling the propelling of the ventilation fan. According to the present invention, when the concentration of carbon dioxide and/or oxygen detected by the carbon dioxide sensor and/or the oxygen sensor reaches the determined value, the control unit generates a control signal which propels the ventilation fan at a rotation rate varying in accordance with the concentration of carbon dioxide and/or varying inversely with the concentration of oxygen to enable ventilation via the ventilation opening.

It is an object of the present invention to provide an automatic ventilation control system comprising various components which include improved features capable of solving the above problem and offering advantages such as:

- reducing energy consumption for air conditioning operation;

- keeping the cooled air within the premise or the target area when the ventilation system is not in operation;

- reducing noises caused by the ventilation fan

- enabling display of data for the user.

BRIEF DESCRIPTIO OF THE DRAWINGS

Fig. 1 shows the automatic ventilation control system which includes a control unit which is a stand-alone control unit.

Fig. 2 shows the automatic ventilation control system which includes a control unit which is integrated in the indoor unit (IU) of the air conditioner.

DETAILED DESCRIPTION

The automatic ventilation control system according to the present invention will now be described in further detail with reference to the accompanying drawings.

Figs. 1 and 2 show an exemplary embodiment of the automatic ventilation control system according to the present invention which should not be construed as limiting the invention to such embodiment in any way.

The automatic ventilation control system according to the present invention comprises a ventilation fan 1 mounted in a ventilation opening, an inlet shutter 2 which is openable and closable installed at the air inlet, a gas sensor 3 which includes a carbon dioxide sensor 3.1 and/or the oxygen sensor 3.2 for detecting the concentration of carbon dioxide and/or oxygen, and a control unit 4 which receives the signal from the carbon dioxide sensor 3.1 and/or the oxygen sensor 3 .2 for controlling the propelling of the ventilation fan 1 . According to the present invention, when the concentration of carbon dioxide and/or oxygen detected by the carbon dioxide sensor 3 . 1 and/or the oxygen sensor 3 .2 reaches the detennined value, the control unit 4 generates a control signal which propels the ventilation fan 1 at a rotation rate varying in accordance with the concentration of carbon dioxide and/or varying inversely with the concentration of oxygen to enable ventilation via the ventilation opening.

According to the present invention, the control unit 4 controls the propelling of the ventilation fan 1 at a determined rotation rate varying in accordance with the concentration of carbon dioxide as follows:

a rotation rate of 0 % of the maximum rotation rate when the concentration of carbon dioxide detected by the carbon dioxide sensor (3.1) is in a range of 380 to 420 PPM which is a normal value for the outdoor environment in general;

a rotation rate of 30 % of the maximum rotation rate when the concentration of carbon dioxide detected by the carbon dioxide sensor (3 . 1 ) is in a range of higher than 420 to 700 PPM which slightly exceeds the normal value;

a rotation rate of 50 % of the maximum rotation rate when the concentration of carbon dioxide detected by the carbon dioxide sensor (3 . 1 ) is in a range of higher than 700 to 1000 PPM which fairly exceeds the normal value; and

a rotation rate of 1 0 0 % of the maximum rotation rate when the concentration of carbon dioxide detected by the carbon dioxide sensor (3 . 1 ) is in a range of higher than 1000 PPM which largely exceeds the normal value to the extent that it causes breathing difficulty, fatigue, and discomfort.

According to the aforementioned embodiment, the control unit 4 generates the ventilation system activation/deactivation control signal capable of controlling the ventilation fan speed or the ventilation rate based on the carbon dioxide concentration with minimal impact on the premise's temperature. Such system is advantageous in that it can reduce the energy required for the air conditioning operation. Moreover, if the rotation of the ventilation fan 1 is not at its maximum rotation rate, the sound of the ventilation fan also decreases.

According to the present invention, the control unit 4 controls the inlet shutter 2 to close when the ventilation fan 1 rotates at the rotation rate of 0 % of the maximum rotation rate and controls the inlet shutter 2 to open when the ventilation fan 1 rotates at the rotation rate of 30, 50 or 100 % of the maximum rotation rate.

The aforementioned embodiment offers an advantage of keeping the cooled air from leaking out when the ventilation fan 1 rotates at the rotation rate of 0 % of the maximum rotation rate. According to the present invention, as shown in Fig. 1 , the control unit 4 is a standalone control unit.

According to the present invention, as shown in Fig. 2, the control unit 4 is integrated in the indoor unit (IU) of the air conditioner.

The aforementioned embodiment further offers the advantage of allowing the user to select, from a variety of the installation options, an option best-suited for the operational condition of the control unit 4.

According to the present invention, the automatic ventilation control system further comprises the outlet shutter 5 which closes when the ventilation fan 1 rotates at the rotation rate of 0 % of the maximum rotation rate and opens when the ventilation fan 1 rotates at the rotation rate of 30, 50 or 100 % of the maximum rotation rate.

The aforementioned embodiment also offers the advantage of keeping the cooled air from leaking out when the ventilation fan 1 rotates at the rotation rate of 0 % of the maximum rotation rate.

According to the present invention, the automatic ventilation control system further comprises a wireless communication module 6 connected to the control unit 4 for sending data regarding the concentration of carbon dioxide and/or oxygen, the rotation rate of the ventilation fan 1 , the opening/closing status of the inlet shutter 2 and the opening/closing status of the outlet shutter 5 to user's data receiving device.

According to the present invention, the user's data receiving device is a wireless or wired device such as smart phone, tablet, mobile computer or a data receiving device with or without display screen.

The aforementioned embodiment offers the advantage of allowing the air conditioner user to be informed of the condition within the premise and/or the ventilation-related data such as the concentration of carbon dioxide and/or oxygen, the rotation rate of the ventilation fan 1 , the opening/closing status of the inlet shutter 2 and the opening/closing status of the outlet shutter 5, etc.

The automatic ventilation control system according to the present invention is used for split type air conditioner.

The automatic ventilation control system according to the present invention comprises various components which include improved features offering a number of advantages as mentioned above, however, it should be appreciated that the automatic ventilation control system according to the present invention is not limited to said components which includes said features. Modifications and changes can still be made to the automatic ventilation control system according to the present invention. Also, the present invention can be embodied in any other ways which allow the achievement of similar technical effects. Such modifications and changes are considered to be within the spirit and the scope of the present invention.