2. Description of Related Art An air purification device commonly used to purify the air in a house or an office is known to produce a healthy indoor environment by removing various viruses, bacteria, tobacco smoke, etc. which would otherwise give out unpleasant odors. The use of the air purification device makes the indoor environment very pleasant and helps adjust the human body's balance. Air purification is achieved by the action of negative ions generated by an ion generator incorporated within the purification device.

Such a purification device, however, uses a separate fan for creating a convection of indoor airs, which necessitates accommodating related parts such as a driving motor in the device. This kind of device has a disadvantage because it occupies a large space due to its large volume.

Recent versions of air purification devices do not employ fans described above for the purpose of miniaturizing the device. These devices, however, experience problems in their purifying ability due to the limited convection of air. Furthermore, since these miniaturized purification devices cover limited areas, a large number of the purification devices need to be installed to cover large areas which can be costly.

Moreover, such purification devices require individual installation and maintenance, and multiple outlets for supplying power to these devices, which increases costs associated with the installation and use of purification devices.

To overcome these problems, Korean Patent No. 1997-6047 discloses a compactly structured conventional air purification device 1 as shown in Fig. 1. As

shown in Fig. 1, the device 1 is integrated with multiple lamps 2 and a negative ion generator 3. The lamps 2 are engaged with a housing 4 of the air purification device 1 for providing illumination.

The negative ion generator 3 generates negative ions for purifying the air. There are, however, drawbacks associated with the device 1. Because the device 1 is configured to generate a fixed amount of negative ions on a continuous basis, the device 1 consumes much power. Further, since the negative ions are generated using high voltages that generate much heat, overheating of the device 1 occurs and the continuous use of the lamps is deemed extremely unsafe.

Hence, there has been a long felt need in the art for an improved air purification device which solves the aforementioned problems and other problems associated with conventional air purification devices.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an air purification device which can purify indoor air without using fans and which can function an illumination device.

It is another object of the present invention to provide an illumination device which can be rapidly turned on even at low ambient temperatures.

It is still another object of the present invention to provide an air purification device which eliminates the necessity of using fans, and thus lends itself to a simple manufacture in a compact size.

It is still another object of the present invention to provide an air purification device which is configured to control selectively the degree of air purification provided by the device based on the intensity of light illumination provided by the device, which prevents overheating of the device and provides a continuous and safe use of the device.

Briefly described, the present invention is directed a device for purifying air, includes a housing having an end portion supplied with power, at least one illumination unit engaged with the housing for emitting light to illuminate areas, an air purifying unit,

engaged with the housing, for generating negative ions to purify air, and a sensor for detecting an amount of light emitted by the illumination unit and controlling an amount of negative ions generated by the air purifying unit based on this detection.

Furthermore, the present invention is directed to a method of providing air purification, the method comprising the steps of providing a housing having an end portion supplied with power; providing at least one illumination unit engaged with the housing for emitting light to illuminate areas; providing air purifying means, engaged with the housing, for generating negative ions to purify air; and providing a sensor for detecting an amount of light emitted by the illumination unit and controlling an amount of negative ions generated by the air purifying means based on this detection.

Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: Fig. 1 is a perspective view of a conventional air purification device; Fig. 2 is a perspective view of an air purification device according to one embodiment of the present invention; Fig. 3 is a partially cutaway exploded view of a negative ion generator of the air purification device of Fig. 2 according to one embodiment of the present invention; Fig. 4 is a sectional view of the air purification device of Fig. 2 with an enlarged view according to one embodiment of the present invention;

Fig. 5 is a sectional view of the air purification device cut along line A-A of Fig.

4; Fig. 6 is a side view of an ion collecting panel according to one embodiment of the present invention; Figs 7a and 7b are, respectively, perspective views of an inverter and an amplification device which can be used in the air purification device of Fig. 2 according to one embodiment of the present invention; and Fig. 8 is a perspective view of an air purification device according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention is directed to an air purification device capable of providing mainly two functions: illumination such as in a lamp, and air purification. The air purification device includes a sensor for detecting the intensity of the illumination provided by an illumination unit to control the amount of negative ions being generated by the device. This prevents overheating of the device and allows a safe and continuous use of the device.

Referring now in detail to the drawings for the purpose of illustrating the preferred embodiment of the present invention, Fig. 2 is a perspective view of an air purification device 100 according to one embodiment of the present invention. As shown in Fig. 2, the air purification device 100 includes a housing 10, at least one lamp or illumination unit 12 engaged with the housing 10, electrodes 11 attached to the bottom of the housing 10, and a negative ion generator 30 engaged with the housing 10.

These components are operatively coupled.

The housing 10 is divided into upper and lower parts 10a and 10b which can be individually produced and assembled together as one unit. The electrodes 11 are spiraled shaped, e. g., in the shape of a screw, and are attached to the bottom of the lower part 1 0b of the housing 10. The electrodes 11 are assembled with a

conventional power socket (not shown) to receive supply voltages from an external power source, e. g., AC 117/220V power supply. The negative ion generator 30 includes a cover 39 and a plurality of through holes 38 formed on the upper surface of the cover 39. On the upper surface of the housing 10, an opening 26 is formed. The opening 26 is used herein to detect the amount or intensity of illumination generated by the lamps 12. The use of the opening 26 will be discussed in more detail below. The height of the negative ion generator 30 is significantly less (e. g., about l/2 thereof) than the height of the lamps 12.

In this embodiment, three lamps 12 are engaged with the housing 10. In the cases where two or three lamps are used, the lamps 12 are preferably positioned a certain space 13 apart from the center of the housing 10 so that the lamps 12 are positioned at an equal distance from each other around the negative ion generator 30.

The lamps 12 are U-shaped tubes, but can be any other types of tubes or lamps known in the art. If the lamps 12 are used as fluorescent lamps, the lamps 12 are equipped to provide conventional illumination functions. If the lamps 12 are used as ultraviolet lamps, the lamps 12 are equipped to generate ultraviolet rays which sterilize and eliminate various viruses.

Fig. 4 is a sectional view of the air purification device 100 of Fig. 2 with an enlarged view, and Fig. 5 is a sectional view of the air purification device cut along line A-A of Fig. 4, according to one embodiment of the present invention. As shown in Figs. 2,4 and 5, the inner circumferential surface of the housing 10 has first and second pairs of supporting members 14a and 14b. The first pair of supporting members 14a supports an amplification device 20 inside the housing 10. The amplification device 20 amplifies power or voltages received from the electrodes 11 into high voltages such as a DC voltage of approximately 7,000-10,000 V. The amplification device 20 may include, but are not limited to, a transformer 22 and other related electronic components and circuitry 23 disposed on a printed circuit board (PCB) 21. The second pair of supporting members 14b supports an inverter 24 for supplying power to the lamps 12.

The operation of the inverter 24 and the amplification device 20 is well known in the art.

The air purification device 100 further includes a negative ion controlling sensor 50 disposed on or above the inverter 24 inside the housing 10. The negative ion controlling sensor 50 controls the amount of negative ions generated by the device 100 based on the intensity or the amount of illumination generated by the lamps 12. This is accomplished as the sensor 50 detects the intensity of the illumination by the lamps 12 through the opening 26 disposed at the upper surface of the housing 10, and electrically controls the amount of negative ions generated by the negative ion generator 30, e. g., by controlling the voltage supplied by the inverter 24 to the negative ion generator 30.

The lower part lOb of the housing 10 includes a plurality of through holes 15 for allowing heat to escape from the inside of the housing 10. In the middle of the upper surface of the housing 10, assembly holes 16,17 are disposed which are concentric to each other.

Fig. 3 is a partially cutaway exploded view of the negative ion generator 30 of the air purification device 100 according to one embodiment of the present invention.

As shown in Fig. 3, the negative ion generator 30 is disposed within the space 13 between or adjacent the lamps 12. The negative ion generator 30 includes an ion collecting panel 31 functioning as a cathode, and an electron gun 34 functioning as an anode. The ion collecting panel 31 has a cylindrical configuration with an open top and bottom. The outer circumferential surface of the ion collecting panel 31 includes a plurality of through holes 32 arranged at regular intervals to form an inlet (or an outlet) for the air. These through holes 32 take a circular shape and are rounded off at the inner circumferential surface of the ion collecting panel 31 (Fig. 6). Extensions 33 are formed at the lower end of the ion collecting panel 31. The extensions 33 are configured to fit into the assembly holes 16 defined on the upper surface of the housing

10 to be secured therein. The highly amplified voltage from the amplification device 20 is applied to the end of any one of the extensions 33.

The electron gun 34 is installed at the center portion within the ion collecting panel 31 so that it is spaced apart at a constant distance from the inner circumferential surface of the ion collecting panel 31. The electron gun 34 can be made with a material such as copper, aluminum, brass, etc. The electron gun 34 includes a plurality of discharge electrodes 35 which are arranged at regular intervals and which extend in the longitudinal direction. The outer edges of the discharge electrodes 35 are sharply shaped.

As shown in Figs. 3 and 4, the electron gun 34 has fixed ends 36a and 36b formed respectively at the upper and lower portions of the gun 34. The length of the end 36b is longer than that of the end 36a. The ends 36a and 36b may be formed by machining after the discharge electrodes 35 are formed by extrusion. One skilled in the art would understand that a proper number of the discharge electrodes 35 can be selected depending on the driving capacity of the amplification device 20. The ends 36a and 36b are respectively fit into first and second insulating members 37a and 37b. The end 36b is inserted through the second insulating member 37b such that the bottom portion of the end 36b is exposed. A reference voltage of the amplification device 20 is applied to the exposed bottom portion of the end 36b, whereby negative ions may be generated at the discharge electrodes 35 of the electron gun 34.

Outer circumferential surfaces of the first and second insulating members 37a and 37b have a corrugated shape. The cover 39 having the plurality of through holes 38 is disposed at the upper surface of the first insulating member 37a. On the lower surface of the cover 39, a flange 40 is formed to be fit into the upper end of the ion collecting panel 31. On the lower portion of the second insulating member 37b, a boss 41 is formed to be fit into the center holes 17 of the housing 10 to be secured therein.

Each of the PCB 21 of the amplification device 20, and the inverter 24 includes a plurality of heat-discharging holes 25 as shown in Figs. 7a and 7b. Any heat

generated within the housing, e. g., from the amplification device 20 and/or the inverter 24 can be exhausted through the heat-discharging holes 25 and then through the plurality of through holes 38.

The operation of the air purification device 100 is as follows according to one embodiment of the present invention. The electrodes 11 are assembled with a conventional power socket (not shown) and a power switch (not shown) disposed at the housing 10 is turned on, whereby power is supplied to the electrodes 11, the amplification device 20 and the inverter 24. The inverter 24 supplies power to the lamps 12 and the lamps 12 emit light therefrom. The amplification device 20 generates and supplies amplified voltages to the negative ion generator 30 to generate negative ions. Particularly, the anode voltage generated by the amplification device 20 is applied to the fixed end 36b of the electron gun 34 while the cathode voltage generated by the amplification device 20 is applied to the extension (s) 33 of the ion collecting panel 31. Depending on the voltage supplied to the negative ion generator 30 by the amplification device 20, the amount of negative ions generated by the negative ion generator 30 can vary. The negative ion controlling sensor 50 disposed close to the opening 26 (e. g., directly underneath the opening 26) detects the amount or intensity of illumination generated by the lamps 12 (and/or distribution of dusts at the indoor). Then, depending on the detection results, the controlling sensor 50 which is electrically connected to the amplification device 20, controls the amount of voltage supplied to the negative ion generator 30 by the amplification device 20, so that the amount of negative ions generated by the generator 30 (i. e., amount of air purification) can selectively varied. In lieu of the sensor 50, other negative ion controlling sensors can be used in the present invention as long as they are able to vary the amount of negative ions generated by the negative ion generator 30 based on the amount of illumination generated by the lamps 12.

Any heat generated within the housing 10, e. g., by the amplification device 20 and/or inverter 24, can be exhausted out through the heat-discharging holes 25. This also helps with a continuous and safe operation of the lamps 12 and the negative ion generator 30.

When the lamps 12 are turned on, a convection current is spontaneously formed around the negative ion generator 30 in the indoor air by the action of the heat emitted from the lamps 12. Accordingly, the air enters through the through holes 32 and 38.

The air which enters these holes 32 and 38 is purified within the ion collecting panel 31 where negative ions generated from the discharge electrodes 35 are collected. The purified air then exits through the through holes 32 and 38 serving as outlets.

Fig. 8 is a perspective view of an air purification device 200 according to another embodiment of the present invention. As shown in Fig. 8, the air purification device 200 is identical to the air purification device 100 of Fig. 2, except for the addition of an electric plug 60 engaged with the electrodes 11. The device 200 provides the electric plug 60 integrally therein for directly plugging the device 200 into outlets or other appropriate receptacles.

Accordingly, the present invention provides a unique air purification device which provides effectively both light illumination and air purification, which does not require a separate fan to create a convection of air, which prevents overheating of the device by the use of the sensor 50 and the through holes 15, and which promotes a safe and continuous use of the device.

The invention being thus described it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included in the scope of the following claims.