Abstract:
Disclosed is an air purifier with a small size, having an excellent air purifying capacity, capable of preventing a large amount of ozone from being generated, the ozone harmful to a human body. The air purifier includes a case, a pair of discharge electrodes provided at upper and lower parts of the case, a ground electrode provided between the pair of discharge electrodes, a pair of insulating dielectric layers provided on upper and lower surfaces of the ground electrode, and a power source coupled respectively to the ground electrode and the discharge electrode so as to supply voltage thereto.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of Korean Application No. P2004-52254, filed on Jul. 6, 2004, which is hereby incorporated by reference as if fully set forth herein. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an air purifier, and more particularly, to an air purifier having an excellent air purifying function, although the size of which is small, and preventing a large amount of ozone which is harmful to a human body from being generated. 
   2. Discussion of the Related Art 
   In general, an air purifier removing dust and bad smell for a pleasant atmosphere is widely used in a living room of a general home, interior of a car, and such places many people gathers as restaurants, hospitals, and offices. 
   The air purifier is usually used independently. It is however a trend that the air purifier is used as a supplementary device mounted to home appliances such as an air conditioner. In other words, recently, many home appliances having not only cooling/heating and ventilating functions but also air purifying function have been manufactured. 
     FIG. 1  illustrates a diagram schematically showing a related art air purifier, and  FIG. 2  illustrates a diagram showing a corona discharge generated from the related art air purifier. Referring to  FIG. 1 , the related art air purifier includes a case  10  having opened top and bottom surfaces, a plurality of ground electrodes  20  and a plurality of discharge electrodes  30  provided in the case  10 . 
   The plurality of ground electrodes  20  are spaced apart a predetermined distance from each other in the case. One of the discharge electrodes  30  is provided between every other consecutive ground electrodes  20 . In this case, each ground electrode  20  includes a rectangular plate, and each discharge electrode  30  includes a round wire. 
   The discharge electrode  30  and the ground electrode  20  are spaced apart a predetermined interval from each other, the predetermined distance being more than a common number cm, and respectively coupled with a power source  50  (Refer to  FIG. 2 ) for supplying a high voltage. On upper and lower surfaces of the case  10 , a net  40  is provided for preventing large impurities from being entered into the case  10 . 
   An operating principle of the related art air purifier structured as above-mentioned will be briefly described as follows. Referring to  FIG. 2 , when a voltage is supplied by the power source to the ground electrode  20  the discharge electrode  30 , a corona discharge for ionizing surrounding air is generated between the ground electrode  20  the discharge electrode  30 . 
   Due to the corona discharge, anions and ozone separating contaminants contained in air and sterilizing germs are generated around the electrode. Accordingly, the air entered into the air purifier is purified by the anions and ozone. 
   Meanwhile, the corona discharge is generated when a high voltage of more than 5 KV is supplied to the ground electrode  20  and the discharge electrode  30 . In this case, a voltage generating the corona discharge is called an onset discharge, and the onset discharge is different depending on an interval between the discharge electrode  30  and the ground electrode  20 . 
   The related art air purifier in accordance with the related art has following problems. First, since the air purifier in accordance with the related art has a plurality of discharge electrodes and ground electrodes, there is a limitation in miniaturizing it. Particularly, when an air purifier is provided in a home appliance, there is a problem that the whole size of the home appliance is increased. 
   Second, the related art air purifier generates a plurality of ozone during the corona generation. The higher a voltage supplied to an electrode is, the more amount of ozone is generated. Ozone being a strong acid substance, performs a role of disassembling organic matters in air, but is harmless to a human body. 
   Therefore, there is a problem that the related art air purifier demands a post-cleaning process for removing ozone generated after the corona discharge. 
   SUMMARY OF THE INVENTION 
   Accordingly, the present invention is directed to an air purifier that substantially obviates one or more problems due to limitations and disadvantages of the related art. 
   An object of the present invention is to provide an air purifier with a small size, having an excellent air purifying capacity, capable of preventing a large amount of ozone from being generated, the ozone harmful to a human body. 
   Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
   To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, an air purifier includes a case; a pair of discharge electrodes provided at upper and lower parts of the case; a ground electrode provided between the pair of discharge electrodes; a pair of insulating dielectric layers provided on upper and lower surfaces of the ground electrode; and a power source coupled respectively to the ground electrode and the discharge electrode so as to supply voltage thereto. 
   The discharge electrode is provided with at least one discharge tip elongated toward the ground electrode. In this case, it is desirable that the discharge tip and the discharge electrode are formed as a single body. 
   The power source supplies a high frequency alternating voltage to the discharge electrode and the ground electrode. The discharge electrode is provided with at least one discharge tip elongated toward the ground electrode, and the discharge tip is spaced from the insulating dielectric layer by a predetermined gap for discharge. 
   In this case, it is desirable that the gap is changed according to voltage frequency, and the discharge electrode is vertically movable. 
   Meanwhile, the case is divided into a plurality of spaces by a partition, each space having the discharge electrode and the ground electrode provided therein, and the insulating dielectric layer comprises a ceramic. 
   In another aspect of the present invention, an air conditioner comprising a cabinet; an inlet formed on a front surface of the cabinet; a fan for drawing in room air through the inlet into the cabinet; an interior heat exchanger for exchanging heat between room air flowed into the cabinet and the interior air thereof; a case provided in the cabinet; a pair of discharge electrodes provided to face each other at upper and lower parts of the case; a ground electrode provided between the discharge electrodes; a pair of insulating dielectric layers provided at upper and lower surfaces of the ground electrode; and a power source coupled respectively with the ground electrode and the discharge electrode so as to supply voltage. In this case, the case is provided at the inlet  12 , and the case is provided to be parallel to a flow direction of room air flowed thereinto through the inlet. 
   The discharge electrode comprises at least one discharge tip elongated toward the ground electrode, and the discharge tip and the discharge electrode are formed as a single body. 
   The power source supplies a high frequency alternating voltage to the discharge electrode and the ground electrode. The discharge electrode is provided with at least one discharge tip elongated toward the ground electrode, and the discharge tip is maintained at predetermined distance from the insulating dielectric layer so as to discharge. 
   In this case, the gap is changed according to voltage frequency supplied by the power source. Meanwhile, the discharge electrode is vertically movable. The case is divided into a plurality of spaces by a partition, each space respectively having the discharge electrode and the ground electrode therein, and the insulating dielectric layer comprises a ceramic. 
   It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings; 
       FIG. 1  illustrates a diagram schematically showing a related art air purifier; 
       FIG. 2  illustrates a diagram showing a corona discharge generated from the related art air purifier; 
       FIG. 3  illustrates a diagram showing a front side of an air purifier in accordance with the present invention; 
       FIG. 4  illustrates a diagram showing a side of the air purifier in accordance with the present invention; and 
       FIG. 5  illustrates a diagram showing an air conditioner having the air purifier in accordance with the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
     FIG. 3  illustrates a diagram showing a front side of an air purifier in accordance with the present invention, and  FIG. 4  illustrates a diagram showing a side of the air purifier in accordance with the present invention. Referring to  FIGS. 3 and 4 , the air purifier in accordance with the present invention includes a case  110 , a pair of discharge electrodes  130  and a ground electrode  120  provided in the case  110 , a pair of insulating dielectric layers  140 , and a power source (not shown) coupled respectively with the discharge electrode  130  and the ground electrode  140 . 
   The discharge electrodes  130  is provided at an upper part and a lower part of the case  110  to face each other, and the ground electrode  120  is provided between the discharge electrode  130 . In this case, the ground electrode  120  is formed in a rectangular plate form. 
   The pair of insulating dielectric layers  140  are provided on upper and lower surfaces of the ground electrode  120 . In other words, contrary to the conventional corona discharge, the pair of insulating dielectric layers  140  are provided between the discharge electrode  130  and the ground electrode  120 . 
   Such structure allows a glow discharge to generate consistently between the discharge electrode  130  and the ground electrode  120 . Although it is desirable that the insulating dielectric layer is made of ceramic, it is not essential. 
   The power source supplies an alternating voltage to the discharge electrode  130  and the ground electrode  120 . In this instance, it is desirable that the power source supplies a high frequency alternating voltage to the discharge electrode  130  and the ground electrode  120  because the higher frequency of the alternating voltage is, the easier the discharge is generated at the electrode. 
   Meanwhile, at least one discharge tip  132  elongated toward the ground electrode  120  is provided at the discharge electrode  130 . The discharge tip  132 , which is centered by electric charges when the voltage is supplied to the discharge electrode  130 , performs a role of decreasing the onset voltage for discharge. It is desirable that the discharge tip  132  and the discharge electrode  130  are formed as a single body. 
   The discharge tip  132  is spaced apart a predetermined distance from the insulating dielectric layer  140 . In other words, the discharge tip  132  maintains a predetermined gap from the insulating dielectric layer  140  so as to discharge. 
   In this case, it is desirable that the gap  150  is changed according to the frequency of the voltage supplied by the power source. For example, when the frequency of the voltage is higher than 1 kHz, the gap is less than 2 mm. The discharge electrode  130  is provided to be rotatable up and down for controlling the gap  150  according to the frequency change of the voltage. 
   In the mean time, interior of the case  100  is divided into a plurality of spaces by a partition  160 . The discharge electrode  130  and the ground electrode  120  are separately provided in each of the spaces. Such structure allows a large amount of anions, OH Radical, and Ultraviolet rays are generated, enabling a large amount of air is purified in a short period of time. 
   An operating process of the air purifier  100  in accordance with the present invention will be described as follows. First, when the power source supplies a voltage larger than the onset voltage to the discharge electrode  130  and the ground electrode  120 , the insulation between the discharge electrode  130  and the ground electrode  120  is broken, thus the discharge is generated. 
   In this case, compared to the conventional corona discharge, the onset voltage is remarkably lowered by the discharge tip  132  formed at the discharge electrode  130  as aforementioned. When the voltage is supplied respectively to the electrodes, an electric charge is built up at the insulating dielectric layer  140 , and the glow discharge is consistently generated between the discharge electrode  130  and the ground electrode  120  by the built up electric charge. 
   In the mean time, once the discharge is started, an electrode with negative electricity is discharged from the discharge electrode  130  toward a space between the discharge electrode  130  and the insulating dielectric layer  140 , and the electrode discharged from the discharge electrode  130  bumps into gas molecule, thereby generating anions, OH radical, and ultraviolet rays. The anions, OH radical, and ultraviolet rays purify air by oxidizing and disassembling contaminants contained in air. 
   Meanwhile, the air purifier in accordance with the present invention as aforementioned is provided in a home appliance such as an air conditioner, and used. 
     FIG. 5  illustrates a diagram showing an air conditioner having the air purifier in accordance with the present invention. Referring to  FIG. 5 , the air purifier includes a cabinet  60 , a fan  70 , an interior heat exchanger  80 , and an air purifier  100 . An inlet  90  is formed on a front surface of the cabinet  60 , and the fan  70  draws in room air through the inlet  90  into the cabinet  60 . The interior heat exchanger  80  exchanges heat between interior air and the room air drawn into the cabinet  60 . 
   As aforementioned, the air purifier  100  includes a case  110 , a plurality of discharge electrodes  130  and a plurality of ground electrodes  120 , and a plurality of insulating dielectric layers  140 . In this case, it is desirable that the case  110  is provided at the inlet  90 . When the case  110  is provided at the inlet  90 , contaminants are prevented from being stuck on the interior heat exchanger  80  or the fan  70  by purifying room air flowed into the cabinet  60 . It is desirable that the case  110  is provided to be parallel to room air flowed through the inlet  90  so as to prevent the room airflow from being interfered by the case  110 . 
   The air conditioner purifies air flowed into the cabinet  60  through the inlet  90  by using the air purifier  100 . The air purifier  100  may be provided at various home appliances such as not only the air purifier but also a ventilating system. The air purifier in accordance with the present invention has following effects. 
   First, the air purifier in accordance with the present invention obtains a consistent glow discharge by using a charge built-up phenomenon of an insulating dielectric layer. Accordingly, a large amount of anions and OH radicals are obtained compared to a related art, and thus excellent sterilization and purification effects are obtained. 
   Second, since the air purifier in accordance with the present invention has an onset voltage lower than a related art corona discharge, the size of a power source for supplying a voltage can be reduced. Therefore, the air purifier in accordance with the present invention can be easily provided in the home appliances such as the air conditioner. 
   Also, since the onset voltage is low, a large amount of ozone is prevented from being generated. Accordingly, a post-cleaning process for cleaning the ozone is not required, and a manufacturing process and parts for the ozone cleaning process is not required as well. Therefore, size and manufacturing cost of the air purifier are lowered. 
   It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.