Air circulation type vacuum cleaner

Abstract: The present invention relates to an air circulation type vacuum cleaner comprising a casing (1) having a suction port and an exhaust port separately, a suction blower (2) placed so as to be consecutive to the suction port of the casing (1) in order to suck impurities with surrounding air, a suction fan (4) having a dust collect filter (3) placed so as to be consecutive to the outlet side of the suction blower (2) in order to filter the impurities from the sucked air and a fan motor (5) for generating suction force, at least one reflux pipe (10) arranged its inlet portion is placed on the discharge side of the suction fan having the fan motor (5) in order to return the discharge air discharged from the suction fan (4) to the suction side, and at least one ejector (20) installed on the outlet side of the reflux pipe in order to jet the discharge air with high speed.

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow channel system of a vacuum cleaner, in particular to an air circulation type vacuum cleaner which is capable of doubling suction force besides suction force of a suction fan by circulating discharged air to the suction side again and inducing vacuum pressure_on the suction side. 2. Description of the Prior Art In the general vacuum cleaner, an one-direction suction method for sucking dusts by using only suction force generated by a suction fan is mainly used, in this case because a bottom surface of a suction blower is adsorbed to a surface to be cleaned, suction ability of the vacuum cleaner lowers a lot. In the consideration of the problem, an air circulation method (Re : Japan patent official bulletin No. 31-62814) is represented, the method refluxes part of the air wind generated by the suction fan to the suction blower again, jets it with a certain pressure, and sucks the dusts while blowing the dusts. As described above, in the air circulation method, because the air wind circulated from the suction fan has to blow the dusts on the bottom surface to be cleaned with a certain discharge pressure and suck the dusts with a certain suction pressure, the air circulation type vacuum cleaner has a problem to control discharge pressure of circulation air and suction pressure of the suction fan. In addition, because sectional area of the suction blower lengthens by expanding the reflux flow channel of the air from the discharge side of the blow fan to the suction blower, the conventional air circulation type vacuum cleaner has a problem to clean narrow place. Therefore, the conventional one-directional suction type vacuum cleaner is used in general. FIG.1 is a schematic view illustrating a flow channel system of the conventional one-bodied vacuum cleaner adapting the one-directional suction method. As depicted in FIG.1, the conventional one-directional suction type one-bodied vacuum cleaner comprises a casing 1 having a suction port (no reference numeral) and an exhaust port (no reference numeral) on the both upper and lower ends, a suction blower 2 placed so as to be consecutive to the suction port side inside of the casing 1 in order to suck impurities with surrounding air, a dust collect filter 3 placed so as to be consecutive to an outlet side of the suction blower 2 in order to filter the impurities included in the sucked air, a suction fan 4 placed so as to be consecutive to the outlet side of the dust collect filter 4 in order to generate the suction force, and a fan motor 5 placed so as to be consecutive to the discharge side of the suction fan 4 in order to generate the operating force for rotating the suction fan 4. The suction blower 2 is formed as a frustum conical shape getting narrower toward the outlet. The dust collect filter 3 is formed so as to make its crosssectional area include the outlet side of the suction blower 2, and the suction fan 4 is a centrifugal fan having a diffuser used in general in the vacuum cleaner. In the flow channel system of the conventional one-bodied vacuum cleaner, the suction fan 4 generates the suction force while rotating by the operation of the fan motor 5, the suction force is transmitted to the inlet side of the suction blower 2 after passing through the dust collect filter 3, and sucks the impurities on the place to be cleaned with the air. After that, the air sucked to the suction blower 2 passes the dust collect filter 3 consecutively placed to the suction blower 2, during the process the impurities are left by being filtered by the dust collect filter 3, the air directly passes the dust collect filter 3, is sucked to the inlet side of the suction fan 4, is discharged through the diffuser (not shown), cools the fan motor 5 consecutively placed to the discharge side of the suction fan 4, and is discharged to the outside of the vacuum cleaner through a ventilation hole (not shown) of the casing 1 placed on the rear side of the fan motor 5. However, in the structure of the flow system of the conventional one-bodied vacuum cleaner, the air and impurities are sucked together by the suction force of the suction fan 4 transmitted to the inlet side of the suction blower 2 by the operation of the fan motor 5, when the suction force generated from the suction fan 4 is small, the ability of the vacuum cleaner lowers, in the consideration of it when the suction force increases by increasing the capacity of the fan motor 5, the power consumption increases and the discharge noise in proportion to the rotating speed of the suction fan 4 increases together. Document DE-A-4140630 also discloses a vacuum cleaner as recited in the preamble of claim 1. This vacuum cleaner includes a wide sectioned duct which returns filtered discharge air from the suction fan into a pipe opening tangentially into a cylindrical chamber having an annular space which contains a helical guide flank in order to form a cyclonic flow for only permitting to clean fine dust. SMMARY OF THE INVENTION In order to solve above-mentioned problem of a flow channel system of the conventional one-bodied vacuum cleaner, the object of the present invention is to provide a vacuum cleaner which is capable of doubling suction force for sucking impurities with any kinds of dusts while keeping capacity of a fan motor as same. In order to achieve this object, the present invention provides a cleaner according to claim 1. BRIEF DESCRIPTION OF THE DRAWINGS FIG.1 is a schematic view illustrating a flow channel system of the conventional one-bodied vacuum cleaner. FIG.2 is a schematic view illustrating a flow channel system of an onebodied vacuum cleaner according to the embodiment of the present invention. FIG.3 is a profile illustrating an ejector of the one-bodied vacuum cleaner according to the present invention. FIG.4 is a schematic view illustrating the other embodiment of the flow channel system of the one-bodied vacuum cleaner according to the present invention. FIG.5 is a schematic view illustrating the another embodiment of the flow channel system of the one-bodied vacuum cleaner according to the present invention. FIG.6 is a schematic view illustrating the another embodiment of the flow channel system of the one-bodied vacuum cleaner according to the present invention. FIG.7 is a schematic view illustrating the another embodiment of the flow channel system of the one-bodied vacuum cleaner according to the present invention. FIG.8 is a schematic view illustrating the another embodiment of the flow channel system of the one-bodied vacuum cleaner according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Hereinafter, an air circulation type vacuum cleaner according to the embodiment of the present invention will now be described with reference to accompanying drawings. FIG.2 is a schematic view illustrating a flow channel system of an one-bodied vacuum cleaner according to the embodiment of the present invention. FIG.3 is a profile illustrating an ejector of the one-bodied vacuum cleaner according to the present invention. As depicted in FIG.2 and 3, the air circulation one-bodied vacuum cleaner according to the present invention comprises a casing 1 having a suction port (no reference numeral) on the lower end and an exhaust port (no reference numeral) on the upper end, a suction blower 2 placed inside of the casing 1 so as to be consecutive to the suction port of the casing 1 in order to suck impurities with surrounding air, a dust collect filter 3 placed so as to be consecutive to the outlet side of the suction blower 2 in order to filter the impurities from the sucked air, a suction fan 4 placed on the straight line so as to be consecutive to the outlet side of the dust collect filter 3 in order to generate suction force for sucking the impurities with air, a fan motor 5 for operating the suction fan 4, a reflux pipe 10 arranged its inlet end is placed on the outlet side of the suction fan 4 in order to return the air discharged from the suction fan 4 to the inlet side and its outlet end is placed between the suction blower 2 and dust collect filter 3, and an ejector 20 connected with the outlet end of the reflux pipe 10 in order to jet the returned air as high speed to the same direction with outer air. The suction blower 2 is formed as a frustum conical shape so as to be narrower toward the outlet. The dust collect filter 3 is formed so as to make its crosssectional area include the outlet side of the suction blower 2, and the suction fan 4 is a centrifugal fan having a diffuser used in general in the vacuum cleaner. The diffuser (not shown) is installed around the suction fan 4 in order to make the discharged air have pressure energy by surrounding the fan wing (no reference numeral) and at the same time make the discharged air flow to the fan motor 5. As depicted in FIG.2, it is advisable to form the reflux pipe 10 as a plane pipe having same diameter in order to minimize flow resistance, but it is also advisable to form the reflux pipe 10 so as to get its diameter of the outlet end smaller than the diameter of the inlet end gradually. In addition, as depicted in FIG.2, it is advisable to form a flow channel groove 11 having a spiral shape on the inner circumference of the reflux pipe 10 in order to clean inside of the pipe by the air circulating inside of the reflux pipe 10 as the spiral shape. As depicted in FIG.3, the ejector 20 comprises an ejector nozzle 21 installed so as to get its discharge end 21 a consecutive to the outlet end of the reflux pipe 10 toward same direction with the inlet flow channel of the sucker air, and an ejector diffuser 22 installed so as to accept the ejector nozzle 21 by having an air flow channel R between the outlet side of the suction blower 2 and inlet side of the dust collect filter 3. Parts overlapped with the conventional technology will have same reference numerals. An non-described reference numeral 22a is an inlet end of the ejector diffuser, and 22b is an outlet end of the ejector diffuser. The general operation of the one-bodied air circulation vacuum cleaner according to the present invention is similar with the conventional technology. In other words, the suction force is generated while the suction fan 4 rotates by the operation of the fan motor 5, the suction force is transmitted to the inlet side of the suction blower 2 through the dust collect filter 3, and sucks the impurities on the place to be cleaned with the air. After that, the air sucked into the suction blower 2 passes the dust collect filter 3 placed so as to be consecutive to the suction blower 2 with the air, during the process the dusts are filtered by the dust collect filter 3, however the air passes the dust collect filter 3, is sucked into the inlet side of the suction fan 4, passes the diffuser (not shown) of the suction fan 4, is discharged to the fan motor 5, the air cools the fan motor 5, part of the air is discharged to the external of the vacuum cleaner through the exhaust port (no reference numeral) of the casing 1, the rest of the air is sucked into the reflux pipe 10 and circulates. Herein, the air sucked into the reflux pipe 10 is induced between the suction blower 2 and dust collect filter 3 along the reflux pipe 10 as suppressed state, is jeted as high speed to the same direction with the sucked air through the ejector nozzle 21, vacuum state is partially formed around the ejector nozzle 21, according to this, the genuine suction force by the suction fan 4 and suction force by the vacuum pressure are added, accordingly the total suction force about the outer air and impurities increases, and the suction ability of the vacuum cleaner having same motor capacity can increase a lot. In addition, the total suction force of the vacuum cleaner increases by using the reflux pipe 10 for returning the discharged air into the inlet side of the suction fan 4 and the ejector 20 for jetting the returned high pressure discharge gas as high speed, accordingly the present invention can minimize the manufacture cost increase due to the efficiency improvement of the vacuum cleaner or maintenance cost increase due to mishaps because the structure of the present invention is simple and easy to use. In addition, there is no need to extend the reflux pipe 10 to the suction blower 2, in particular when the present invention is adapted to a chargeable small vacuum cleaner which has weak suction force and is suitable to clean small place, the suction force improves a lot, but the longitudinal dimension of the suction blower 2 does not increase, accordingly the chargeable small vacuum cleaner can maintain its size with improved cleaning power and it can clean every nook and corner of narrow place. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be constructed broadly within its sprit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalence of such meets and bounds are therefore intended to be embraced by the appended claims. For example, as depicted in FIG.4, in the other embodiment of the present invention, when the suction fan 4 including the suction blower 2, dust collect filter 3, and fan motor 5 is placed consecutively inside of the casing 1, the inlet end of the reflux pipe 100 is placed on the discharge side of the suction fan 4, the ejector 20 arranged on the outlet end of the reflux pipe 100 can be placed between the dust collect filter 3 and suction fan 4, in this case the pressure lowering problem of the returned air can be prevented as a certain degree because the length of the reflux pipe 100 is shorter than the embodiment of the present invention. As depicted in FIG.5, in the another embodiment of the present invention, the ejector 20 arranged on the outlet end of the reflux pipe 200 can be placed inside of the suction blower 2, in this case the longitudinal dimension of the suction blower 2 increases a little, but the vertical length where the ejector 20 is placed is removed, accordingly the length of the vacuum cleaner is shorter. In addition, in this case, as depicted in FIG.6, it is advisable to minimize the flow resistance of the discharge air by reducing the length of the reflux pipe 300 by arranging the suction fan 4 including the fan motor 5 on the outlet side of the suction blower 2 consecutively and the dust collect filter 3 on the discharge side of the suction fan 4. As depicted in FGI.7, in the another embodiment of the present invention, when there is a plurality of the reflux pipes 400, the inlet end of the each reflux pipe is placed on the discharge side of the suction fan 4, the all outlet ends of the plurality of the reflux pipes 400 are connected with the one ejector, or as depicted in FIG.8, the ejectors 20a, 20B connected with the outlet end of the each reflux pipe 510, 520 are placed on the different portion each other such as between the suction blower 2 and dust collect filter 3 or between the dust collect filter 3 and suction fan 4 or inside of the suction blower 2 ect.. As described above, the each embodiment according to the present invention can be adapted more effectively to the one-bodied vacuum cleaner comprising a suction unit and a motor unit in the same casing, but it can be adapted also to a separation type vacuum cleaner comprising the suction unit and motor unit separately in different casings.

Claims: An air circulation type vacuum cleaner, comprising: a casing (1) having a suction port and an exhaust port; a suction blower (2) having an inlet placed on the suction port of the casing (1) to intake air with impurities through the suction port of the casing (1) and an outlet a suction fan (4) having an inlet and an outlet; and a dust collecting filter (3) placed after the outlet of the suction blower (2), for removing a portion of the impurities from the air; characterized in that the cleaner further comprises: at least one reflux pipe having an inlet placed on the outlet side of the suction fan (4) and an outlet arranged to return air discharged from the outlet side of the suction fan (4) to the inlet side of the suction fan (4); and at least one ejector (20) installed on the outlet side of the at least one reflux pipe for discharging air towards the suction fan (4) to thereby increase a suction of the vacuum cleaner. The air circulation type vacuum cleaner according to claim 1, wherein the outlet end of the ejector (20) is placed between the suction port of the casing (1) and dust collecting filter (3). The air circulation type vacuum cleaner according to claim 1, wherein the outlet end of the ejector (20) is placed between the dust collecting filter (3) and the suction fan (4). The air circulation type vacuum cleaner according to claim 1, wherein the ejector (20) is arranged inside of the suction blower (2). The air circulation type vacuum cleaner according to claim 4, wherein the suction fan (4) is placed on the outlet side of the suction blower (2), and the dust collecting filter (3) is placed on the outlet side of the suction fan (4). The air circulation type vacuum cleaner according to claim 1, wherein the inlet end of the reflux pipe is placed on the outlet side of the suction fan (4) and the ejector (20) is placed between the suction blower (2) and dust collecting filter (3), between the dust collecting filter (3) and the suction fan (4), or inside of the suction blower (2). The air circulation type vacuum cleaner according to any claims 1 to 6, wherein the reflux pipe is formed so as to have the same diameter from the inlet end to the outlet end. The air circulation type vacuum cleaner according to claim 7, wherein the reflux pipe comprises a flow channel groove (11) having a spiral shape on the inner circumference. The air circulation type vacuum cleaner according to any claims 1 to 6, wherein the reflux pipe is formed such that its diameter becomes smaller from the inlet end to the outlet end. The air circulation type vacuum cleaner according to claim 9, wherein the reflux pipe comprises a flow channel groove (11) having a spiral shape on the inner circumference.

Inventors: LEE SEONG BIN, LEE, SEONG BIN
Applicants: LG ELECTRONICS INC, LG ELECTRONICS INC.
Application year: 2000
Main classification: A47L7
IPC codes: A47L9, A47L5, A47L7