Filter assembly for vacuum cleaner

A filter assembly for a vacuum cleaner is provided. The filter assembly includes a filter case and a primary filter attached to an outside of the filter case. The primary filter filters out fine dust contained in air from which relatively large dust has been separated. A secondary filter provided in the filter case filters Out fine dust remaining in the air after passing through the primary filter. The primary and secondary filters are removeable from the filter case so that dust and dirt accumulated in the filter assembly during the process of filtering the fine dust can be cleaned out, and the filters can be used semi-permanently.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to a vacuum cleaner, and more particularly, to a vacuum cleaner having an improved inner filter structure for a dust collecting unit thereof.

2. Description of the Prior Art

A vacuum cleaner is an apparatus which sucks air containing foreign materials using a vacuum pressure generated by a vacuum motor installed in a main body of the vacuum cleaner, filters out foreign materials such as the dust and dirt in the main body, and then collects and discharges the dust and dirt.

A cyclonic vacuum cleaner which has recently been widely used is designed to filter out dust and dirt in such a manner that relatively heavy dust and dirt are moved outward by a centrifugal force in air flow swirling at a high speed and collected in a specific dust collecting chamber, whereas fine dust and dirt which are not filtered out by the cyclonic method are filtered by a filter such as a pleated filter.

FIG. 1shows a vacuum cleaner for performing a general cyclonic filtering process.

Referring toFIG. 1, the vacuum cleaner comprises a main body10in which a suction means for sucking air in a room is installed, a flexible connection tube24which is connected to the main body10to communicate with the interior of the main body, a variable length extension tube22which is connected to an end of the connection tube24to communicate with the interior of the connection tube, and a suction nozzle21for sucking the air containing foreign materials from a floor by means of a suction force generated in the main body10.

Further, in the main body10is installed a dust collecting unit11which is detachably mounted to a rear side of the main body. The dust collecting unit11causes the air sucked from the suction nozzle21to be introduced therein and then the dust and dirt in the air to be collected in a cyclonic fashion. Further, at one side of the main body10is formed a discharge portion19for discharging the air, from which the foreign materials are filtered out through the dust collecting unit11, to the atmosphere.

A pair of wheels18for traveling the main body10on the floor are rotatably installed on a lower surface of the main body10. Further, a power cord16for supplying the vacuum cleaner with electric power is installed at another side of the main body10. The power cord16can be wound around a cord reel (not shown) in the main body and stored in the main body.

The dust collecting unit11includes a grip12for allowing a user to hold the unit when it is rearward mounted to or demounted from the main body10. Further, a handle14, which the user can grip when intending to carry the vacuum cleaner, is installed at a top surface of the main body10.

In the dust collecting unit11, an additional fine filter (not shown) can be mounted as a secondary dust collecting means for filtering out fine dust and dirt which remain after a primary cyclonic dust collecting process has been performed. As the vacuum cleaner is repeatedly used for a long time, fine dust and dirt are continuously accumulated in the, fine filter. Therefore, there is inconvenience in that the accumulated dust and dirt should be repeatedly cleaned.

Further, there is a problem in that if the fine dust and dirt are continuously accumulated in the fine filter, the filter should be frequently replaced with a new one.

SUMMARY OF THE INVENTION

The present invention is conceived to solve the aforementioned problems in the prior art. Accordingly, an object of the present invention is to provide a filter assembly for a vacuum cleaner, capable of easily removing dust and dirt accumulated in a filter during in the process of filtering the fine dust contained in air.

Another object of the present invention is to provide a filter assembly for a vacuum cleaner of which a fine filter can be semi-permanently used.

According to an aspect of the present invention for achieving the objects, there is provided a filter assembly for a vacuum cleaner, comprising a primary filter for filtering out fine dust contained in air from which relatively large dust has been separated in a cyclonic manner, a filter case with the primary filter attached to an outer periphery thereof and a plurality of air vent holes formed on the outer periphery thereof, and a secondary filter mounted into the filter case for filtering out again fine dust contained in the air which has passed through the primary filter.

According to another aspect of the present invention, there is provided a filter assembly for a vacuum cleaner, comprising a primary filter for filtering out fine dust and dirt contained in sucked air, a filter case with the primary filter attached to an outer periphery thereof and a plurality of air vent holes formed on the outer periphery thereof, a secondary filter mounted into the filter case for filtering out again fine dust contained in the air which has passed through the primary filter, wherein the secondary filter is a pleated filter made of a flexible material.

According to a further aspect of the present invention, there is provided a filter assembly for a vacuum cleaner, comprising a primary filter for filtering out fine dust and dirt contained in sucked air, a filter case with the primary filter attached to an outer periphery thereof and a plurality of air vent holes formed on the outer periphery thereof, a secondary filter mounted into the filter case for filtering out again fine dust contained in the air which has passed through the primary filter, wherein the filter case is provided with a closed surface, through which the air does not pass, at a portion of the outer periphery.

According to a still further aspect of the present invention, there is provided a dust collecting unit for a vacuum cleaner, comprising a dust collecting casing in which an air inlet and an air outlet are formed, and a filter assembly which is mounted to the dust collecting casing and includes a primary filter for filtering out fine dust and dirt contained in sucked air and a secondary filter for filtering out again fine dust contained in air which has passed through the primary filter.

According to the filter assembly of the present invention so constructed, there are advantages in that the filter cleaning operation can be quickly and conveniently performed and life of the filter can be prolonged.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Hereinafter, preferred embodiments of a dust collecting unit for a vacuum cleaner according to the present invention will be described in detail with reference to the accompanying drawings. Throughout the drawings, like reference numerals are used to designate like elements.

FIG. 2is a front perspective view of a dust collecting unit of a cyclonic vacuum cleaner according to the present invention, andFIG. 3is an exploded perspective view of the dust collecting unit of the cyclonic vacuum cleaner according to the present invention.

Referring toFIGS. 2 and 3, the vacuum cleaner of the present invention comprises a cover30for covering an upper end of the dust collecting unit11to protect inner parts and hermetically sealing the unit to prevent sucked air from leaking out, a filter assembly40installed downward from the cover30around an outlet31formed near the center of the cover, and a dust collecting casing80attached to a bottom side of the cover30.

More specifically, near the center of the cover30is formed the outlet31through which clean air with dust and dirt filtered out from the air sucked in the dust collecting casing80is discharged. The filter assembly40in which a fine filtering structure is implemented is positioned below the outlet31to filter out fine particles. The filter assembly40is cylindrical and is formed with the fine filtering structure on an outer periphery thereof. The air flowing into the filter assembly40is filtrated by the filter assembly40and then discharged to the outside through the outlet31.

Further, the dust collecting casing80comprises an inlet71through which air is introduced from the main body of the vacuum cleaner into the dust collecting unit, a cylindrical dust separation chamber70in which the air sucked through the inlet71swirls by a centrifugal force and the dust and dirt are separated from the air by their own weight, and a main dust collecting chamber50which is defined in the dust separation chamber70below a dust separating plate73SO that the dust and dirt dropped by their own weight are accumulated in the dust collecting chamber through a predetermined opening74.

More specifically, the filter assembly40comprises a filter casing41with a plurality of holes formed on an outer periphery thereof and a large air discharge opening formed at an upper end thereof, a pleated filter42mounted into the filter casing41, and a filter cover43which is attached to the upper end of the filter casing41to allow the filter casing41to be fixed to a bottom surface of the cover30.

The filter assembly40will be operated in such a manner that fine dust is filtered out by the pleated filter42after relatively large dust has been filtered out while the air containing the dust swirls in the dust separating chamber70, and the clean air from which the fine dust has been separated by the pleated filter42is discharged to the outside through the outlet31.

FIG. 4is an exploded perspective view of the filter assembly for a vacuum cleaner according to a preferred embodiment of the present invention. Referring toFIG. 4, the filter assembly40comprises a cylindrical filter case81with a plurality of air vent holes formed on an outer periphery thereof, a fine filter82attached to the outer periphery of the filter case81, a pleated filter83mounted into the filter case81, and a filter cover84attached to an upper end of the filter case81.

More specifically, a lower end of the filter case81is closed whereas the upper end thereof is opened to allow air to be discharged to the outside. However, the positions of air vent holes and air discharge opening of the filter casing81may vary according to a specific shape of the dust collecting unit for filtering out the relative large dust.

Further, the fine filter82is a mesh filter for finely filtering out the fine dust after the relatively large dust has been filtered out by the cyclonic operation. The dust to be filtered generally adheres to an outer surface of the fine filter82. Furthermore, it is preferred that the fine filter82be attached to the outer periphery of the filter case81using an adhesive. Moreover, the fine filter82may be attached either to the whole outer periphery of the filter case81or to only specific regions of the filter case using the adhesive in order to prevent the fine holes thereof from being blocked while the fine filter82is mounted to the filter case81.

In this embodiment, the fine filter82and the pleated filter83function as primary and secondary filters, respectively. Thus, the filter assembly with the two filters can provide the dust collecting unit with a dual filtering function in addition to the cyclonic dust collection function.

The pleated filter83can be fitted and securely seated into the filter case81, and it can also easily detach from the filter case81when a user wishes to remove the dust and dirt therefrom. The filter cover84is used to attach the filter assembly40to the dust collecting unit11. A specific shape, structure and arrangement of the filter cover84can vary according to a specific structure and shape of the dust collecting unit.

Hereinafter, an operation of the aforementioned filter assembly for the dust collecting unit will be described.

The relatively large dust is filtered by a cyclonic swirling phenomenon generated in the dust collecting unit, and then, only fine dust remains in the air. Such fine dust is first filtered by the fine filter82. That is, the fine dust contained in the air is first filtered out to a nearly perfect level.

Further, the fine dust that has not yet been filtered by the fine filter82is perfectly filtered by the pleated filter83and then discharged through the opening formed at the upper end of the filter assembly40.

At this time, since the dust filtered by the fine filter82adheres to the outer surface of the fine filter82, the fine filter82can be more easily cleaned as compared with in the prior art.

In addition, since the fine dust is primarily filtered by the fine filter82, an amount of the fine dust to be accumulated on the pleated filter83is considerably reduced, and thus, life and cleaning period of the pleated filter can be remarkably prolonged.

FIG. 5shows a preferred example of the pleated filter. In this example, the pleated filter83comprises pleated portions83athat are closely pleated several times to increase a surface area to be contacted with the dust, and flexible fixing portions83bfor fixing upper and lower ends of the pleated portions83a.It is preferred that the pleated portions83abe generally made of a vulcanized fiber etc. so that it can be prevented from being easily deformed by a suction force of a motor (not shown) and can also be washed with water for its semi-permanent use.

The flexible fixing portions83bare made of rubber or urethane such that their shapes can be flexibly changed in accordance with an external pressure. The flexible fixing portions83bare attached to the upper and lower ends of the pleated portions83a,respectively, so that the pleated portions83acan be maintained to their specific shapes. Desired regions of the pleated portions83amay become relatively widened by modifying the flexible fixing portions83baccording to a desired shape as shown in this figure.

As described above, since the desired regions of the pleated portions83acan be widened by the flexible fixing portions83b,the dust held between the widened pleated portions83ccan be easily removed using a brush, etc.

FIG. 6is an exploded perspective view of a filter assembly for a vacuum cleaner according to another preferred embodiment of the present invention.

As shown inFIG. 6, the filter assembly of this embodiment is identical with the aforementioned embodiment in many respects. That is, a fine filter92, a filter case91and a filter cover94of this embodiment are the same as those of the aforementioned embodiment, except that the pleated filter83is replaced with a porous filter93in this embodiment. As an example of the porous filter93, sponge or the like may be used. The porous filter93is generally made of a resin in which a plurality of holes are formed to filter out the dust.

Similarly to the aforementioned embodiment, the fine dust and dirt that has not yet been filtered by the fine filter92can also be perfectly filtered by the porous filter93.

In the meantime, so long as the secondary filters, i.e. porous filter93and the pleated filter83, can clearly filtrate the air that was already filtered by the fine filter92and82, any shapes of secondary filters can be used in the filter assembly regardless of the kinds thereof.

In this embodiment, the fine dust and dirt adhering to the surface of the fine filter92can be easily cleaned or washed, and the life of the porous filter93can also be prolonged since a large amount of the dust and dirt is not accumulated in the porous filter93due to the fine filter92.

FIG. 7is a perspective view showing a modified example of the filter case81or91. Any one of the filter cases81and91is installed at the center of the dust collecting casing80, and the air sucked from the inlet71swirls around the filter case in a cyclonic manner. In this example, a portion of the filter case is formed with a closed structure through which air does not pass. That is, a plurality of openings81bserving as air vent holes are formed at a portion of the outer periphery of the filter case, whereas a closed surface81awith no openings is formed at the other portion of the outer periphery of the filter case.

If the filter case so constructed is installed such that the flow of air introduced from the inlet71of the dust collecting casing80is directed to the closed surface81a,it is possible to prevent the introduced air from directly flowing into the filter assembly40without the cyclonic dust collection during the swirling process of the introduced air. Therefore, dust collection efficiency of the vacuum cleaner can be further maximized.

The present invention can be applied to various types of the vacuum cleaners, and particularly, to the cyclonic vacuum cleaner so that convenience of use can be further improved.

According to the present invention, there is an advantage in that it is possible to easily remove the dust and dirt accumulated in the filter assembly during the process of filtering the fine dust contained in the air. Further, the expected life span of the filter assembly can be more prolonged because the fine filter can be used semi-permanently. Furthermore, the cleaning efficiency of the vacuum cleaner can also be improved due to the dual filtering function in addition to the cyclonic dust collection of the dust collection unit.

Although the present invention has been described in connection with the preferred embodiments thereof shown in the accompanying drawings, it is a mere example of the present invention. It can also be understood by those skilled in the art that various changes and modifications thereof can be made thereto without departing from the scope and spirit of the present invention defined by the claims. Therefore, the true scope of the present invention should be defined by the technical spirit of the appended claims.