DESCRIPTION OF PREFERRED EMBODIMENTS

[0024] Hereinafter are described preferred embodiments of the present invention with reference to FIGS. 1 through 9, in which front or back, top or bottom of the apparatus is defined, based on the posture illustrated in FIGS. 1 through 3. In FIGS. 1 through 9, reference numeral 1 designates a cleaner body which comprises an electric motor 2 and a fan 3 mounted to the rotational shaft of the electric motor 2 provided in a bottom portion of the inside of the cleaner body 1, thereby constructing a fan unit 4.

[0025] The rear side of the cleaner body 1 is integrally formed with a projecting portion 6 which includes a suction tube 5 thereinside. A suction unit 8 with a dust-laden air suction opening 7 is removably provided at the lower end of the suction tube 5. A holder 9, serving as an attachment portion, is provided in a lower opening 1A of the cleaner body 1. The holder 9 comprises a bottom plate 10, outside and inside guide walls 11 and 12 which are protruded therefrom, and a guiding duct 13 which extends tangentially with respect to each of the guide walls 11 and 12. The guiding duct 13 is connected to the suction tube 5 so as to guide the air sucked from the suction tube 5 to a hereinafter described vortex flow generating means. The guiding duct 13 is formed with an inclined guiding plate 14 and a top guiding plate 15 communicating therewith, thereby forming an air path 16 for guiding the air from the suction tube 5 into the inside of the cleaner. The outer peripheral surface of the outside guide wall 11 is formed with a collar 11A, said collar 11A being fitted into a groove 17 formed on the inside peripheral surface of the lower opening 1A, thereby attaching the holder 9 to the cleaner body 1.

[0026] By attaching the holder 9 to the cleaner body 1 this way, the lower opening 1A of the cleaner body 1 is closed by the bottom plate 10 of the holder 9. However, the cleaner body 1 is allowed to communicate the outside thereof with the inside thereof through a suction opening 20 defined by the inside guide wall 12. Then, into the inside of the inside guide wall 12 that defines the said suction hole 20 is inserted a guide member 19A protruding from the peripheral edge of an air suction hole 19 of the cleaner body 1, so that the airflow by the fan unit 4 is allowed to flow through the inside of the inside guide wall 12. Also, the peripheral inner surface of the inside guide wall 12 is formed with a partition plate 12A, said partition plate 12A being horizontal, located below a lower end of the guide member 19A, including a suction hole 20A with a first packing 40 of a U-shaped cross section being fitted therein. The first packing 40 has such a U-shaped cross section that it closely contacts the peripheral outer surface of a small cylindrical portion 19B which is integrally fixed to the distal end of the aforesaid guide member 19A, while the rear side thereof is integrally formed with a fin-shaped packing 40A for close contact with a hereinafter described a filter case.

[0027] Reference numeral 23 designates a dust collecting container attached to a lower surface of the cleaner body 1, comprising a double cyclone structure consisting of an outer cyclonic cylinder 21 and an inner cyclonic cylinder 22. The outside surface of the outer cyclonic cylinder 21 is integrally formed with a handle 21A, said handle 21A having a hook 24 integrally formed on a distal end thereof, while an outside peripheral portion of the outer cyclonic cylinder 21 is integrally formed at its lower portion with a frame-shaped locker protrusion 25. Also, the cleaner body 1 includes a locking portion 27 for locking the locker protrusion 25, said locker portion 27 being formed in a recess 26 of said projecting portion 6, while a hook stop 28 for hooking the hook 24 thereon is formed at a lower portion of the cleaner body 1.

[0028] The said inner cyclonic cylinder 22 has substantially short frustoconical shape that tapers toward the distal end thereof, having a vortex flow generating member 30 formed integrally with a bottom portion thereof. The vortex flow generating member 30 comprises a skirt 31 of which the diameter is the same as that of the outside guide wall 11 of said holder 9. The skirt 31 is integrally formed with an outer vortex flow generating portion 32 for introducing air from above, i.e., from the said holder 9 side to generate a vortex flow and then guiding the vortex flow thus generated into the outer cyclonic cylinder 21; and an inner vortex flow generating portion 33 for introducing air from below, i.e., from the bottom of the outer cyclonic cylinder 21 to generate a vortex flow and then guiding the vortex flow thus generated into the inside of the inner cyclonic cylinder 22.

[0029] As illustrated in FIGS. 7 and 8, the outer vortex flow generating portion 32 includes a pair of air guides 35, 36 which are inclined so as to communicate with the air path 16 of the said guiding duct 13. On the other hand, the inner vortex flow generating portion 33 comprises an airflow guiding wall 38 which is gently curved from the skirt 31 toward the center thereof so as to guide the air introduced from an air vent 37 formed in a bottom 31A of the skirt 31 to a hereinafter described filter case, as illustrated in FIG. 8. Further, the peripheral outer surface of the skirt 31 is formed with vertically paired flanges 42 for attaching a second packing 41 and a positioning lug 44 which is anchored by a step 43 formed on the inner surface of the outer cyclonic cylinder 21. The upper surface of the second packing 41 is integrally formed with a fin-shaped packing 41A for closely contacting the peripheral surface of the lower end of the cleaner body 1.

[0030] Reference numeral 46 designates a filter case for attaching a mesh filter 45 thereto, said filter case 46 being detachably attached to the inside of the skirt 31. The filter case 46 is shaped like an inverted cup which is provided by integrally extending a cylindrical portion 48 from the perimeter of a bottom plate 47 provided for attaching the mesh filter 45, in a manner surrounding the mesh filter 45. The peripheral outer surface of the lower end of the cylindrical portion 48 is formed with a male thread 49A which is screwed into a female thread 49 which is formed on a peripheral inner surface of the upper end of the inner cyclonic cylinder 22.

[0031] When the filter case 46 is attached to the inner cyclonic cylinder 22 through the screw fastening between the male and female threads 49 and 49A, the opening of the inner cyclonic cylinder 22 is occupied by the filter case 46, while the cylindrical portion 48 of the filter case 46 is surrounded by the skirt 31 of the vortex flow generating member 30. Thus, an air intake opening 50 formed in the cylindrical portion 48 is substantially aligned with the airflow guiding wall 38 of the aforesaid inner vortex flow generating portion 33.

[0032] The cylindrical portion 48 of the filter case 46 defines substantially the same diameter as that of the aforesaid inner guide wall 12 of the holder 9, so that the cylindrical portion 48 of the filter case 46 is substantially aligned with the inner guide wall 12 of the holder 9 with the filter case 46 being fixed to the inner cyclonic cylinder 22, while the bottom plate 47 of the filter case 46 is allowed to abut to the periphery of the opening of the lower end of the suction opening 20 defined by the inner guide wall 12. In the center of the bottom plate 47 (of the filter case 46) is formed an attachment hole 52 for fixing the mesh filter 45. The inside of the filter case 46 and the inner cyclonic cylinder 22 is allowed to communicate with the air suction hole 19 of the cleaner body 1, through this attachment hole 52 and the aforesaid suction opening 20. A cylindrical portion 55, serving as a connecting portion, is provided so as to integrally extend upwardly from the perimeter of the attachment hole 52, said cylindrical portion 55 including a collar 55A protruding in the radial direction at a distal end thereof. The collar 55A is closely contacted by the fin-shaped pacing 40A of the first packing 40 attached to the suction hole 20A of the aforesaid partition plate 12A.

[0033] Reference numeral 65 designates an extension cylindrical body connected in series with the distal end of the inner cyclonic cylinder 22. The extension cylindrical body 65 is first expanded moderately from the distal end of the inner cyclonic cylinder 22, and then extends vertically downwardly until it almost reaches a bottom of the outer cyclonic cylinder 21. The bottom of the outer cyclonic cylinder 21 is formed integrally with an annular peripheral wall 66 in a manner that surrounds the distal end of the extension cylindrical body 65, while a flange 67 contacted by a peripheral inner surface of the annular peripheral wall 66 is formed on a peripheral outer surface of the distal end of the extension cylindrical body 65. In the meantime, reference numeral 68 designates a stick-like handle, which is pivotably connected with the cleaner body 1, while reference numeral 69 designates a charging stand, supporting the cleaner body 1.

[0034] Next, the action of the cyclonic vacuum cleaner of the embodiment will be described. The holder 9 is fixedly fitted in the opening 1A of the cleaner body 1, while the first packing 40 fitted in the suction hole 20A of the holder 9 is brought into close contact with the small cylindrical portion 19B of the guide member 19A which protrudes from the air suction hole 19 of the cleaner body 1, thereby sealing the peripheral edge of the suction hole 20A provided for allowing the airflow generated by the fan unit 4 to flow therethrough. The guiding duct 13 of the holder 9 is connected to the suction tube 5.

[0035] Initially when using the cyclonic vacuum cleaner of the embodiment, the inner cyclonic cylinder 22 is attached to the outer cyclonic cylinder 21. In other words, the inner cyclonic cylinder 22 is inserted from the opening of the outer cyclonic cylinder 21 so that the positioning lug 44 of the skirt 31 formed in a proximal portion of the inner cyclonic cylinder 22 is abutted against the step 43 formed on the peripheral inner surface of the outer cyclonic cylinder 21, thereby properly positioning the inner cyclonic cylinder 22 relative to the outer cyclonic cylinder 21. Further, the second packing 41 attached to the skirt 31 of the vortex flow generating member 30 integral with the inner cyclonic cylinder 22 is closely contacted by the peripheral inner surface of the outer cyclonic cylinder 21, thereby sealing the gap between the vortex flow generating member 30 and the outer cyclonic cylinder 21.

[0036] Thus way, the outer cyclonic cylinder 21 is coupled with the inner cyclonic cylinder 22 so that the extension cylindrical body 65 connected with the distal end of the inner cyclonic cylinder 22 is accommodated into the inside of the annular peripheral wall 66 formed on the bottom of the outer cyclonic cylinder 21. Then, the male thread 49A formed in the filter case 46 is screwed into the female thread 49 formed on the vortex flow generating member 30, thereby attaching the filter case 46 to the inner cyclonic cylinder 22. At this moment, the filter case 46 is attached to the inner cyclonic cylinder 22 in such a manner that the air intake opening 50 formed in the cylindrical portion 48 of the filter case 46 substantially aligns with the airflow guiding wall 38 of the inner vortex flow generating portion 33 formed in the vortex flow generating member 30. By attaching the filter case 46 to the inner cyclonic cylinder 22 thus way, the outer cyclonic cylinder 21, the inner cyclonic cylinder 22, the vortex flow generating member 30 of the inner cyclonic cylinder 22 and the filter case 46 are assembled into a one-piece structure, and then they are attached to the cleaner body 1.

[0037] In other words, the outer cyclonic cylinder 21 is rotated by hanging the hook 24 of the outer cyclonic cylinder 21 from the hook stop 28 of the cleaner body 1, so that the locker protrusion 25 of the outer cyclonic cylinder 21 is locked by the locking portion 27 of the cleaner body 1, thereby fixing the dust collecting container 23 consisting of the inner and outer cyclonic cylinders 22 and 21, as shown in FIG. 9. Accordingly, the fin-shaped packing 40A integral with the first packing 40 attached to the holder 9 is allowed to closely contact the collar 55A formed on the cylindrical portion 55 of the filter case 46, while the other fin-shaped packing 41A integral with the second packing 41 provided between the inner and the outer cyclonic cylinders 22, 21 is also allowed to closely contact the peripheral surface of the lower end of the cleaner body 1. Thus, the gap between the peripheral edge of the suction opening 20 and the cylindrical portion 55 of the filter case 46 is sealed by the first packing 40 attached to the partition plate 12A of the holder 9. At the same time, the gap between the vortex flow generating member 30 and the outer cyclonic cylinder 21 as well as the respective gaps between the cleaner body 1, the vortex flow generating member 30 and the outer cyclonic cylinder 21 are sealed simultaneously by the second packing 41 to be attached to the skirt 31 of the vortex flow generating member 30. As a result, the prevention of the leakage of airflow can be ensured, using such a small number of packing members 40 and 41.

[0038] When the fan unit 4 is actuated with the dust collecting container 23 being attached to the cleaner body 1, dust-laden air is sucked from the dust-laden air suction opening 7, passing through the suction tube 5, the guiding duct 13 and the vortex flow generating member 30 to reach the inside of the dust collecting container 23. At this moment, as the guiding duct 13 extends tangentially relative to the holder 9 while the air path 16 of the guiding duct 13 communicates with between the air guides 35 and 36 of the outer vortex flow generating portion 32, the air flowing in from the guiding duct 13 is guided by the air path 16 of the guiding duct 13 and the air guides 35, 36 of the outer vortex flow generating portion 32, thus being converted into a vortex flow, falling helically along the peripheral inner surface of the outer cyclonic cylinders 21, thereby removing comparatively heavy dusts contained in the vortex flow therefrom, due to a centrifugal force. When the vortex flow falls down to the bottom of the outer cyclonic cylinders 21, it is then turned upwardly, rising helically along the peripheral outer surface of the inner cyclonic cylinder 22 to reach the vortex flow generating member 30 again. At that moment, the vortex flow rising along the peripheral outer surface of the inner cyclonic cylinder 22 is allowed to flow through the air vent 37 into the inner vortex flow generating means 33, and then it is guided through the air intake opening 50 of the filter case 46 into the inside thereof, flowing along the air guiding wall 38 of the inner vortex flow generating member 33, which is again turned into the vortex flow falling down helically along the peripheral inner surface of the inner cyclonic cylinder 22. When the airflow reaches the bottom of the outer cyclonic cylinder 21, the vortex flow is then turned upwardly in the vicinity of the center thereof. At this moment, comparatively light or fine dusts such as lint-like dusts mixed in the vortex flow are separated from the vortex flow, and accumulated inside the annular peripheral wall 66 formed on the bottom of the outer cyclonic cylinder 21. The vortex flow rising within the inner cyclonic cylinder 22 is allowed to pass through the mesh filter 45 attached to the filter case 46, and it is eventually sucked through the suction opening 20 into the air suction holel9 of the cleaner body 1. It should be noted that the remaining extremely fine dusts are captured by the mesh filter 45 when they are passing therethrough.

[0039] After carrying out a cleaning work this way, the lever 21A formed on the outer cyclonic cylinder 21 is pulled to release the engagement of the locker protrusion 25 of the outer cyclonic cylinder 21 with the locking portion 27 of the cleaner body 1, and then the lower part of the dust collecting container 23 is pulled out sidewise, so that the dust collecting container 23 is detached from the cleaner body 1. Thereafter, the inner cyclonic cylinder 22 is detached from the outer cyclonic cylinder 21 so that the dusts collected in the outer cyclonic cylinder 21 are thrown into a dustbin, while the filter case 46 is detached from the inner cyclonic cylinder 22 so that the dusts adherent to the mesh filter 45 are removed.

[0040] According to the present embodiment, as the vortex flow generating member 30 is formed with the outer vortex flow generating portion 32 and the inner vortex flow generating portion 33, the outer vortex flow generating portion 32 allows the dust-laden air sucked from the dust-laden air suction opening 7 to turn into a downward vortex flow when the fan unit 4 is actuated, so that the comparatively heavy dusts can be removed, while the vortex flow turned upward on the bottom of the outer cyclonic cylinder 21 is allowed to rise along the peripheral outer surface of the inner cyclonic cylinder 22. Then, the inner vortex flow generating portion 33 allows the airflow from below to turn again into a downward vortex flow along the peripheral inner surface of the inner cyclonic cylinder 22, so that the fine dusts that cannot be fully removed by the vortex flow generated in the outer vortex flow generating portion 32 can be separated within the inner cyclonic cylinder 22. By removing dusts in such a multistage manner, the amount of dusts to be captured by the mesh filter 45 at a final stage can be reduced. Accordingly, the dusts can be collected efficiently and reliably without sacrificing suction efficiency.

[0041] Further, the inner cyclonic cylinder 22 is integrally formed at its proximal portion with the vortex flow generating member 30, while said vortex flow generating member 30 is formed integrally with the outer vortex flow generating portion 32 for introducing air from above to generate a vortex flow and then guiding the vortex flow into said outer cyclonic cylinder 21; and the inner vortex flow generating portion 33 for introducing air from below to generate a vortex flow and then guiding the vortex flow into the inside of said inner cyclonic cylinder 22, whereby it is possible to form the inner cyclonic cylinder 22, the vortex flow generating member 30, the outer vortex flow generating portion 32 and the inner vortex flow generating portion 33 into such a compact one-piece structure, so that the outer cyclonic cylinder 21 and the inner cyclonic cylinder 22 are unitized by incorporating the inner cyclonic cylinder 22 thus integrated into the outer cyclonic cylinder 21. As a result, the dust collecting container 23 consisting of the outer cyclonic cylinder 21 and the inner cyclonic cylinder 22 can be easily attached to or detached from the cleaner body 1.

[0042] This is particularly advantageous in that the maintenance works are simplified, as the outer cyclonic cylinder 21 and the inner cyclonic cylinder 22 can be easily detached from the cleaner body 1 when removing dusts collected in the dust collecting container 23 or fine dusts adherent to the mesh filter 45. Further, as the inner cyclonic cylinder 22, the vortex flow generating member 30, the outer vortex flow generating portion 32 and the inner vortex flow generating portion 33 are formed compactly to a one-piece structure, it is possible to diminish portions that need sealing. According to the present embodiment, therefore, the gap between the peripheral edge of the suction hole 20A and the cylindrical portion 55 integrally extending from the peripheral edge of the attachment hole 52 for the filter case 46 is sealed by the first packing 40 attached to the partition plate 12A of the holder 9, while the gap between the vortex flow generating member 30 and the outer cyclonic cylinder 21 as well as the respective gaps between the cleaner body 1, the vortex flow generating member 30 and the outer cyclonic cylinder 21 are sealed at the same time, whereby it is possible to ensure the preventing of the airflow from leaking, using such a small number of the packing members 40 and 41 only.

[0043] Moreover, as the inner cyclonic cylinder 22 is integrally formed with the vortex flow generating member 30 which includes the outer vortex flow generating portion 32 and the inner vortex flow generating portion 33, the vortex flow generated in the outer vortex flow generating portion 32 is not allowed to enter the inner cyclonic cylinder 22, and the vortex generated in the inner vortex flow generating portion 33 is not allowed to enter the outer cyclonic cylinder 21, either, whereby the leakage of airflow can be prevented more reliably.

[0044] Incidentally, the present invention should not be limited to the foregoing embodiments, but may be modified within a scope of the invention. For example, the attachment structure of the dust collection container, the configuration or attachment structure of the vortex flow generating member, the holder, filter case and etc., each relating to the fundamental structure of a vacuum cleaner, may be modified suitably. Whilst a stick-type vacuum cleaner is shown in the foregoing embodiment, the present invention may be applied to any other type of a cyclonic vacuum cleaner.