EP1493373A1

EP1493373A1 - Bagless vacuum cleaner with helical passageway

Info

Publication number: EP1493373A1
Application number: EP03077116A
Authority: EP
Inventors: Billy Yung Kwok Kee
Original assignee: Shell Electric Mfg Holdings Co Ltd
Current assignee: Shell Electric Mfg Holdings Co Ltd
Priority date: 2003-06-20
Filing date: 2003-07-04
Publication date: 2005-01-05
Also published as: CA2432974A1

Abstract

A bagless vacuum cleaner having a removable dust extraction and collection unit. The removable dust extraction and collection unit has a cover (47) which defines an air inlet port (46). The air inlet port includes a helical passageway (86,88) disposed within a peripheral portion of the cover (47). The helical passageway (86,88) directs incoming air to the dust extraction and collection unit in a downwardly directed cyclone flow pattern.

Description

FIELD OF THE INVENTION

This invention relates generally to vacuum cleaners and, more particularly, to bagless vacuum cleaners.

BACKGROUND OF THE INVENTION

Bagless vacuum cleaners have become very popular over the last several years. This popularity is due in large part to the ease with which dust and dirt can be removed from such vacuum cleaners. In old style cloth bag-containing vacuum cleaners, dust and dirt removal is a difficult and awkward process, frequently requiring the user to extend his or her hand into the cloth bag to physically disengage dust clumps. Vacuum cleaners using disposable liner bags minimize the problems associated with cloth bags, but the use of such vacuum cleaners requires the continuous replenishment and installation of disposable liner bags. (Also, owners of older model disposable liner bag-containing vacuum cleaners often find it difficult to locate a source of properly sized replacement liner bags.)
Contrary to these problems associated with bag-containing vacuum cleaners, dirt and dust vacuumed up using bagless vacuum cleaners is conveniently deposited into an easily removable permanent container, from which dust and dirt can be disposed of without the effort associated with cloth bag-containing vacuum cleaners and without having to continually purchase and reinstall disposable liner bags.
The efficiency of bagless vacuum cleaners is dependent upon the "strength" of the cyclone formed within the dust extraction and collection unit of the vacuum cleaner. The stronger the cyclone, the better the separation of dust from the incoming dust-laden air.
Accordingly, there is a need for a bagless vacuum cleaner having improved cyclonic action.

SUMMARY

The invention satisfies this need. The invention is a vacuum cleaner having (a) a chassis having a base unit and a housing unit, the base unit having an air inlet and roller means for moving the vacuum cleaner across a flat surface, (b) an air blower disposed within the chassis, (c) a removable dust extraction and collection unit disposed within the housing unit, the dust extraction and collection unit comprising (i) an enclosed inlet chamber, the inlet chamber being substantially cylindrical in shape, the inlet chamber comprising a bottom wall, at least one generally vertical sidewall, a cover, an upper section and a lower section, and (ii) an enclosed outlet chamber suspended downwardly from the cover and disposed concentrically within the upper section of the inlet chamber, the outlet chamber having a bottom wall and at least one generally vertical side wall, the at least one sidewall having a plurality of inlet apertures, the inlet apertures being disposed in a band around the at least one sidewall, and (d) duct work for serially connecting in fluid communication the air inlet in the base unit, the inlet chamber, the outlet chamber and the air blower, wherein the cover comprises a central portion and a peripheral portion, the central portion defining an air outlet opening for the outlet chamber and the peripheral portion defining an air inlet opening for the inlet chamber, the peripheral portion further defining a helical passageway for directing incoming air to the inlet chamber in a downwardly directed cyclone flow pattern.
In one embodiment, the helical passageway extends at least once around the peripheral portion of the cover. Typically, the helical passageway extends between once and twice around the peripheral portion of the cover.
The helical portion typically comprises an upstream section and a downstream section. In one embodiment, the upstream section comprises a downwardly slanted top wall and a pair of spaced apart side walls. In a typical embodiment, such upstream section has at least one cross-section defining an area between about 5 cm² and about 8 cm², most typically between about 6 cm² and about 7 cm².

DRAWINGS

These features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims and accompanying figures where:
Figure 1 is a perspective view of a vacuum cleaner having features of the invention;
Figure 2 is a rear view of the vacuum cleaner illustrated in Figure 1;
Figure 3 is a diagrammatic cutaway view of the vacuum cleaner illustrated in Figure 1;
Figure 4 is a cross-section of a dust extraction and collection unit in the vacuum cleaner illustrated in Figure 1;
Figure 5 is an exploded perspective view of the cover of the dust extraction and collection unit in the vacuum cleaner illustrated in Figure 4; and
Figure 6 is a second exploded view of the cover illustrated in Figure 5.

DETAILED DESCRIPTION

The following discussion describes in detail one embodiment of the invention and several variations of that embodiment. This discussion should not be construed, however, as limiting the invention to those particular embodiments. Practitioners skilled in the art will recognize numerous other embodiments as well.
The invention is a vacuum cleaner 10 having features which improve upon vacuum cleaners disclosed in my prior patents, U.S. Pat. No. 6,269,518 Bl and U.S. 6,484,350. As illustrated in Figures 1-4, the vacuum cleaner 10 has a chassis 12, an air blower 14 and a dust extraction and collection unit 16. The vacuum cleaner 10 can be a canister-style vacuum cleaner as illustrated in the drawings, or it can be of an upright style (not shown).
The chassis 12 comprises an air inlet 22 wherein dust and dirt is sucked up into the chassis 12.
The chassis 12 further comprises roller means for moving the vacuum cleaner 10 across a flat surface. In the embodiment illustrated in the drawings, such roller means include a pair of wheels 26 disposed on opposite sides of the chassis 12.
The air blower 14 is disposed within the chassis 12. The air blower 14 is typically an electrically driven air blower having a capacity between about 50 m³/hour and about 200 m³/hour. A typical electrical motor 28 for driving the blower operates on ordinary house current and has a power capacity between about 800 watts and about 2000 watts.
The dust extraction and collection unit 16 is disposed within the chassis 12. The dust extraction and collection unit 16 comprises an enclosed inlet chamber 32 and an enclosed outlet chamber 34. The dust extraction and collection unit 16 is illustrated in detail in Figures 3-6.
The inlet chamber 32 is substantially cylindrical in shape with an internal diameter between about 130 mm and about 200 mm, preferably between about 150 mm and about 180 mm. The inlet chamber 32 comprises a body portion 35. The body portion 35 has a bottom wall 36, and at least one generally vertical sidewall 38. The at least one sidewall 38 typically has an interior height between about 200 mm and about 250 mm, most typically between about 220 mm and about 230 mm.
The inlet chamber 32 has an upper section 42 and a lower section 44. The inlet opening 46 of the inlet chamber 32 is configured to provide the ingress of dusty air into the inlet chamber 32 in tangential fashion wherein the ingressing dusty air is caused to downwardly spiral around the internal surface 48 of the at least one inlet chamber body portion sidewall 38.
The inlet chamber 32 is preferably reversibly installable and deinstallable within the chassis 12. In the embodiment illustrated in the drawings, the inlet chamber 32 is reversibly installable and deinstallable within the chassis 12 via a snap-on connection between the inlet chamber walls and the walls of the chassis 12. In another embodiment (not shown), the inlet chamber 32 is reversibly installable and deinstallable within the chassis 12 using a press-fit connection.
The inlet chamber 32 further comprises a removable cover 47. The cover 47 comprises a central portion 60 and a peripheral portion 62. As illustrated in Figures 5 and 6, the cover 47 comprises a base 64 and a peripheral insert 82. The base 64 has a top wall 83 and a downwardly depending circular side wall 84. The cooperation of the circular side wall 84 and the peripheral insert 82 defines a helical passageway 85 having an upstream section 86 and a downstream section 88. The upstream section 86 is attached in fluid tight communication with the inlet opening 46. The upstream section 86 comprises a slanted top wall 90 and a pair of spaced apart side walls 96, the outer of which is provided by the at least one side wall 84 of the base 64. Typically, the vertical height of the pair of spaced apart side walls 96 is about 2.5 cm, and the side walls 96 are spaced apart by a distance of about 2.5 cm. Thus, at least one cross-section of the upstream section of the helical passageway 85 defines an area of between about 5 cm² and about 8 cm², most typically between about 6 cm² and about 7 cm². The peripheral insert 82 comprises a circular collar 98 with a helical flange 100 extending around it. The helical flange 100 provides the slanted top wall 90 in the upstream section 86. Typically, the helical flange 100 extends more than once around the collar 98, most typically between about once and about twice around the collar 98.
The helical passageway 85 guides the incoming air to the inlet chamber 32 over a longer distance than the incoming air is guided in known prior art units. This results in higher air inlet velocities which, in turn, results in higher inlet air accelerations. The net result of the higher air inlet velocities and accelerations is a much stronger cyclone within the inlet chamber 32 than is possible in known prior art units.
The outlet chamber 34 is disposed concentrically within the upper section 42 of the inlet chamber 32. The outlet chamber 34 is suspended from the top wall 83 of the cover 47. The outlet chamber 34 has a bottom wall 50 and at least one generally vertical sidewall 54. The at least one sidewall 54 has an interior height between about 50 mm and about 100 mm, preferably between about 80 mm and about 90 mm.
The at least one sidewall 54 of the outlet chamber 34 is perforated with a plurality of inlet apertures 56, each defining an area between about 3 mm² and about 30 mm². In a typical embodiment, the at least one sidewall 54 defmes between about 1000 and about 1500 inlet apertures 56, preferably between about 1300 and about 1400 inlet apertures 56. Typically each of the inlet apertures 56 is separated from adjoining inlet apertures 56 by a distance of between about 1.5 mm and about 5 mm. The inlet apertures 56 are preferably disposed in a band 58 around the sidewalls 54 of the outlet chamber 34. Typically, the band 58 has a width between about 20 mm and about 50 mm, preferably between about 30 mm and about 40 mm. The band 58 defines a median line (not shown) which divides the uppermost apertures 56 from a substantially equal number of lowermost apertures 56. Typically, the median line is disposed between about 30 mm and about 100 mm above the bottom wall 50 of the outlet chamber 34, preferably between about 50 mm and about 60 mm above the bottom wall 50.
In the embodiments illustrated in the drawings, the bottom wall 50 of the outlet chamber 34 has an X-shaped wall 75 which projects vertically above the bottom wall 50. This X-shaped wall 75 supports the cylindrical filter 76. Typically, such cylindrical filter 76 is made from polypropylene, paper, ceramic or polytetrafluoroethylene having a thickness between about 1.5 mm and about 5 mm.
The cylindrical filter 76 is suspended from the central portion 60 of the cover, such that the cylindrical filter 76 is disposed vertically and concentrically within the outlet chamber 34.
The central portion 60 of the cover 47 defines a top wall opening 78 for the outlet chamber 34.
In a preferred embodiment, the outlet chamber 34 comprises a planar filter 80 disposed across the top wall 78 opening of the outlet chamber 34. In a typical embodiment, such planar filter 80 is made from sponge, fibrous polyethylene, fibrous polypropylene or paper, and typically has a thickness between about 5 mm and about 15 mm.
The invention further comprises duct work 92 for serially connecting in fluid communication the air inlet 22 in the base unit 18, the inlet chamber 32, the outlet chamber 34 and the air blower 14.
It is very important that all such duct work 92 and all connection points within the duct work and between various components in the system and/or the duct work 92 be well-sealed. Even small leaks within the system can markedly decrease efficiency and increase power requirements.
In a preferred embodiment, a blower filter 94 is operatively disposed downstream of the air blower 14. Preferably, such blower filter 94 is a HEPA filter.
The invention has been found to provide a vacuum cleaner with all the conveniences of prior art vacuum cleaners, but with increased dust removal efficiency and without excessive mechanical complexity and resulting expense of manufacture.
Having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.

Claims

A vacuum cleaner comprising:

(a) a chassis having a base unit and a housing unit, the base unit having an air inlet and roller means for moving the vacuum cleaner across a flat surface;

(b) an air blower disposed within the chassis;

(c) a removable dust extraction and collection unit disposed within the housing unit, the dust extraction and collection unit comprising:

(i) an enclosed inlet chamber, the inlet chamber being substantially cylindrical in shape, the inlet chamber comprising a bottom wall, at least one generally vertical sidewall, a cover, an upper section and a lower section; and

(ii) an enclosed outlet chamber suspended downwardly from the cover and disposed concentrically within the upper section of the inlet chamber, the outlet chamber having a bottom wall and at least one generally vertical side wall, the at least one sidewall having a plurality of inlet apertures, the inlet apertures being disposed in a band around the at least one sidewall; and

(d) duct work for serially connecting in fluid communication the air inlet in the base unit, the inlet chamber, the outlet chamber and the air blower;

wherein the cover comprises a central portion and a peripheral portion, the central portion defining an air outlet opening for the outlet chamber and the peripheral portion defining an air inlet opening for the inlet chamber, the peripheral portion further defining a helical passageway for directing incoming air to the inlet chamber in a downwardly directed cyclone flow pattern.
The vacuum cleaner of claim 1 wherein the helical passageway extends at least once around the peripheral portion of the cover.
The vacuum cleaner of claim 1 wherein the helical passageway extends between once and twice around the peripheral portion of the cover.
The vacuum cleaner of claim 1 wherein the helical portion comprises an upstream section and a downstream section, the upstream section comprising a downwardly slanted top wall and a pair of spaced apart side walls.
The vacuum cleaner of claim 1 wherein at least one cross-section of the upstream section of the helical passageway defines an area between about 5 cm² and about 8 cm².
The vacuum cleaner of claim 1 wherein at least one cross-section of the upstream section of the helical passageway defines an area between about 6 cm² and about 7 cm².