U.S. patent application number 11/913622 was filed with the patent office on 2009-12-24 for vacuum cleaner.
This patent application is currently assigned to MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.. Invention is credited to Masami Fukumoto, Masanobu Hirota, Tetsuya Kouda, Makoto Murakami, Koichi Nakano.
Application Number | 20090313783 11/913622 |
Document ID | / |
Family ID | 38563543 |
Filed Date | 2009-12-24 |
United States Patent
Application |
20090313783 |
Kind Code |
A1 |
Nakano; Koichi ; et
al. |
December 24, 2009 |
VACUUM CLEANER
Abstract
A vacuum cleaner is disclosed, and this cleaner maintains
sucking power at a high level while it resists lowering the suction
force although it sucks dust. The vacuum cleaner includes a
cylindrical dust collecting case which takes air in sucked by an
electric air blower and including dust. The case includes a suction
port through which the air including dust flows into the case along
a tangent line, and a dust collector communicates with the port. A
dust filter in the case is placed in an air-duct through which the
case communicates with the electric air blower. This structure
allows whirling airflow in the case to whirl continuously in the
case, so that dust can be removed from the filter even if the dust
attaches to the filter. As a result, sucking airflow can be always
secured.
Inventors: |
Nakano; Koichi; (Osaka,
JP) ; Kouda; Tetsuya; (Osaka, JP) ; Hirota;
Masanobu; (Shiga, JP) ; Murakami; Makoto;
(Osaka, JP) ; Fukumoto; Masami; (Osaka,
JP) |
Correspondence
Address: |
PEARNE & GORDON LLP
1801 EAST 9TH STREET, SUITE 1200
CLEVELAND
OH
44114-3108
US
|
Assignee: |
MATSUSHITA ELECTRIC INDUSTRIAL CO.,
LTD.
Osaka
JP
|
Family ID: |
38563543 |
Appl. No.: |
11/913622 |
Filed: |
March 29, 2007 |
PCT Filed: |
March 29, 2007 |
PCT NO: |
PCT/JP2007/056920 |
371 Date: |
November 5, 2007 |
Current U.S.
Class: |
15/353 |
Current CPC
Class: |
A47L 9/1608 20130101;
A47L 9/1683 20130101; A47L 9/1675 20130101; A47L 9/127 20130101;
A47L 9/26 20130101; A47L 9/20 20130101; A47L 9/1666 20130101 |
Class at
Publication: |
15/353 |
International
Class: |
A47L 9/16 20060101
A47L009/16 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2006 |
JP |
2006-098809 |
Feb 22, 2007 |
JP |
2007-041883 |
Feb 22, 2007 |
JP |
2007-041884 |
Claims
1. A vacuum cleaner comprising: an electric air blower; a dust
separator disposed on an upper stream side of the electric air
blower for taking air in, which air is sucked by the electric air
blower and includes dust; and a dust collector for accommodating
the dust separated by the dust separator, wherein the dust
separator includes a whirling airflow air-duct for running the air,
which is taken in through a suction port and includes the dust, as
whirling airflow, and a dust filter forming at least a part of the
whirling airflow air-duct, and wherein the dust filter is
surrounded by a space, on which suction force of the electric air
blower acts, and an air vent of the dust filter is disposed nearer
to the dust collector than to the suction port so that the whirling
airflow can be generated toward the dust collector.
2. The vacuum cleaner of claim 1, wherein the whirling airflow
air-duct is provided with the dust filter at an entire
circumference.
3. The vacuum cleaner of claim 1, wherein the dust collector is
disposed below the dust filter.
4. The vacuum cleaner of claim 1, wherein the whirling airflow
air-duct forms an approximately cylindrical shape, and the suction
port is disposed along a tangent line of the approximately
cylindrical shape.
5. The vacuum cleaner of any one of claims 1-4, wherein a main
air-duct is formed in the space surrounding the circumference of
the dust filter, and the suction force of the electric air blower
acts on the circumference of the dust filter through the main
air-duct.
6. The vacuum cleaner of claim 5, wherein the dust collector
includes a sub air-duct on which the suction force of the air
blower acts.
7. The vacuum cleaner of claim 6, wherein the sub air-duct runs
from the dust collector through the dust filter and reaches an
exterior of the dust filter.
8. The vacuum cleaner of claim 6, wherein a third dust filter is
disposed in the sub air-duct.
9. The vacuum cleaner of claim 5, wherein the dust filter includes
at least a first dust filter for catching rough dust on an upper
stream side of sucking airflow, and a second dust filter disposed
outer circumference of the first dust filter and on a downstream
side of the sucking airflow for catching fine dust.
10. The vacuum cleaner of claim 9, wherein the dust collector
includes a sub air-duct on which the suction force of the electric
air blower acts.
11. The vacuum cleaner of claim 10, wherein the main air-duct runs
from the whirling airflow air-duct to circumference of the dust
separator via the first dust filter and the second dust filter, and
the sub air-duct runs from the dust collector to the circumference
of the dust separator via a third dust filter and the second dust
filter.
12. The vacuum cleaner of claim 11, wherein the third dust filter
catches rough dust.
13. The vacuum cleaner of claim 9, wherein the first dust filter
includes at least one of punching metal, metal mesh, and resin
mesh.
14. The vacuum cleaner of claim 9, wherein the second dust filter
shapes like a cylinder formed by rounding a pleated member.
15. The vacuum cleaner of claim 14, wherein the pleated member
shapes like letter U and rounded inward at outside of the
cylindrical second dust filter.
16. The vacuum cleaner of claim 1, wherein the dust filter
rotates.
17. The vacuum cleaner of claim 9, wherein at least one of the
first dust filter and the second dust filter rotates.
18. The vacuum cleaner of claim 17, wherein the first dust filter
rotates in step with the second dust filter.
19. The vacuum cleaner of claim 1 further comprising a dust
removing means for removing dust attaching to the dust filter.
20. The vacuum cleaner of claim 16 further comprising a dust
removing means brought into contact with the dust filter
rotating.
21. The vacuum cleaner of claim 17 further comprising a dust
removing means which is brought into contact with at least one of
the first dust filter and the second dust filter rotating, wherein
the dust removing means vibrates the contacted dust filter for
removing dust attaching to the contacted dust filter.
22. The vacuum cleaner of claim 17 further comprising a dust
removing means which is brought into contact with at least one of
the first dust filter and the second dust filter rotating, wherein
the dust removing means removes dust attaching to the contacted
dust filter by scraping or rubbing off the dust from the contacted
dust filter.
23. The vacuum cleaner of claim 19, wherein the dust removing means
moves while it contacts the dust filter for removing dust attaching
to the filter by vibrating the filter, or scraping or rubbing off
the dust from the filter.
24. The vacuum cleaner of claim 8, wherein the third dust filter
shapes like a truncated cone having a lower diameter greater than
an upper diameter, and the truncated cone opens at its upper end
and lower end.
25. The vacuum cleaner of claim 1, wherein the dust filter shapes
like a truncated cone having a lower diameter greater than an upper
diameter.
26. The vacuum cleaner of claim 11, wherein an opening is disposed
at a part of the third dust filter, and a dust removing means is
disposed near the opening, a dust chamber communicating with the
opening is disposed in the dust collector, and dust removed by the
dust removing means passes through the opening before it is
accommodated in the dust chamber.
27. The vacuum cleaner of claim 26, wherein the dust chamber has a
vent hole communicating with the dust collector, and a fourth dust
filter is disposed to the vent hole.
28. The vacuum cleaner of claim 1, wherein the dust collector opens
its bottom for discharging the dust.
29. The vacuum cleaner of claim 1, wherein at least one of the dust
separator and the dust collector at least in part is formed of
see-through material.
30. The vacuum cleaner of claim 1, wherein at least a part of the
dust filter is formed of see-through material.
Description
TECHNICAL FIELD
[0001] The present invention relates to a vacuum cleaner that
employs a reusable dust collecting case.
BACKGROUND ART
[0002] A conventional vacuum cleaner has generated cyclone air
current in its dust collecting case for separating dust from the
sucked air current with centrifugal force, thereby accumulating the
dust in the dust collecting case. This is disclosed in patent
document 1*. However, this conventional structure cannot separate
the dust sufficiently because of the restriction that sucking power
should be kept at a high level, so that the dust accumulated in the
dust collecting case works as a filter and thus fine dust attaches
to accumulated rough dust, thereby resisting to the airflow. As a
result, sucking power is lowered in a short time. Production of the
cyclone air current requires a sucking air duct to be bent greatly,
and whirling airflow is also generated in sucking the air, so that
a pressure loss becomes greater in the sucking air duct starting
from sucking and ending at discharging. As a result, the sucking
power is obliged to lower. *Patent Document 1: Unexamined Japanese
Patent Publication No. 2000-342492.
DISCLOSURE OF INVENTION
[0003] The present invention addresses the foregoing problems, and
aims to provide a vacuum cleaner that sucks dust with the sucking
power maintained at a high level, and the suction force is
difficult to lower while the vacuum cleaner works.
[0004] A vacuum cleaner of the present invention comprises the
following elements in order to solve the foregoing problems:
[0005] an electric air blower;
[0006] a dust separator, for taking air in sucked by the electric
air blower and including dust, placed on the upper stream of the
blower; and
[0007] a dust collector for accommodating the dust separated by the
dust separator,
[0008] wherein the dust separator includes an air duct for whirling
airflow, which air duct runs the air taken from a suction port and
containing the dust, and the dust separator also includes a dust
filter which forms at least a part of the air duct, and the dust
filter is surrounded by space on which the suction force of the
electric air blower acts.
[0009] The foregoing structure of the present invention allows the
dust separator to generate the whirling airflow therein when the
air including the dust flows into the dust separator. The dust
having the whirling component whirls also in a hollow cylinder of
the dust separator, so that rough dust such as lint and hair whirls
and lowers in the hollow cylinder to the dust collector.
[0010] The whirling airflow removes dust attaching to the inner
wall of the hollow cylinder in the dust filter, so that no dust
accumulates in the filter and thus the air-permeability of the
filter can be maintained. The sucked dust accumulates in the dust
collector, and the sucking air-duct running from a suction port to
the electric air blower is secured around the dust filter. As a
result, this structure does not cause to lower an air volume, but
is excellent in maintaining the air volume, so that the vacuum
cleaner of the present invention can be a product of maintenance
free for a long period.
[0011] The air duct running from the suction port to the electric
air blower can separate the dust from the duct without repeating
sharp bends, expansions or shrinkages of the airflow, so that a
sucking power at a high level can be maintained for a long period.
The vacuum cleaner of the present invention thus can be free from
maintenance works for a long period while it maintains sucking
power at a high level, and its suction force is difficult to lower
although it sucks dust.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows an entire view of a vacuum cleaner in
accordance with a first embodiment of the present invention.
[0013] FIG. 2 shows a sectional view illustrating a structure of an
essential part of the vacuum cleaner shown in FIG. 1.
[0014] FIG. 3A shows a front sectional view of a dust collecting
case of the vacuum cleaner shown in FIG. 1.
[0015] FIG. 3B shows a lateral sectional view of the dust
collecting case shown in FIG. 3A.
[0016] FIG. 3C shows a sectional view taken along line A-A in FIG.
3B.
[0017] FIG. 3D shows a sectional view taken along line B-B in FIG.
3B.
[0018] FIG. 4 shows a sectional view of an essential part of a
second dust filter of the vacuum cleaner shown in FIG. 1.
[0019] FIG. 5A shows a plan sectional view illustrating a direction
of airflow near to a suction port of the dust collecting case of
the vacuum cleaner shown in FIG. 1.
[0020] FIG. 5B shows a plan sectional view illustrating a direction
of airflow near to a dust filter of the dust collecting case.
[0021] FIG. 5C shows a vertical sectional view illustrating airflow
running in a vertical direction in the dust collecting case.
[0022] FIG. 6 shows a graph illustrating a relation between an
amount of collected house dust and changes in sucking airflow; the
relation is measured both in the vacuum cleaner shown in FIG. 1 and
another vacuum cleaner for comparison purpose.
[0023] FIG. 7 shows a perspective view of a dust collecting case of
another vacuum cleaner in accordance with the embodiment of the
present invention.
[0024] FIG. 8A shows a lateral sectional view of the dust
collecting case of this another vacuum cleaner in accordance with
the embodiment.
[0025] FIG. 8B shows a sectional view taken along line B-B in FIG.
8A.
[0026] FIG. 9A shows a front sectional view of the dust collecting
case of this another vacuum cleaner in accordance with the
embodiment.
[0027] FIG. 9B shows a sectional view taken along line B-B in FIG.
9A.
[0028] FIG. 10 shows a sectional view of an essential part of a
vacuum cleaner in accordance with a second embodiment of the
present invention.
[0029] FIG. 11A shows a front sectional view of a dust collecting
case of the vacuum cleaner shown in FIG. 10.
[0030] FIG. 11B shows a lateral sectional view of the dust
collecting case shown in FIG. 10.
[0031] FIG. 11C shows a sectional view taken along line A-A in FIG.
11B.
[0032] FIG. 11D shows a sectional view taken along line B-B in FIG.
11B.
[0033] FIG. 12A shows a plan sectional view illustrating a
direction of airflow near to a suction port of the dust collecting
case of the vacuum cleaner shown in FIG. 10.
[0034] FIG. 12B shows a plan sectional view illustrating a
direction of airflow near to a dust filter of the dust collecting
case.
[0035] FIG. 12C shows a vertical sectional view illustrating
airflow running in a vertical direction in the dust collecting
case.
[0036] FIG. 13 shows a graph illustrating a relation between an
amount of collected house dust and changes in sucking airflow; the
relation is measured both in the vacuum cleaner shown in FIG. 10
and another vacuum cleaner for comparison purpose.
[0037] FIG. 14 shows a sectional view illustrating a structure of
an essential part of a driving gear of a vacuum cleaner in
accordance with a third embodiment of the present invention.
[0038] FIG. 15 shows a graph illustrating a relation between an
amount of collected house dust and changes in sucking airflow of
the vacuum cleaner shown in FIG. 14.
[0039] FIG. 16A is a lateral sectional view of a dust collecting
case in accordance with a fourth embodiment of the present
invention.
[0040] FIG. 16B shows a sectional view taken along line B-B in FIG.
16A.
[0041] FIG. 17 shows a sectional view of the operation of an
essential part of a first dust removing means of the vacuum
cleaner.
[0042] FIG. 18 shows a perspective view of a dust collecting case
of another vacuum cleaner in accordance with the fourth
embodiment.
[0043] FIG. 19A shows a lateral sectional view of a dust collecting
case in accordance with a fifth embodiment of the present
invention.
[0044] FIG. 19B shows a sectional view taken along line B-B in FIG.
19A.
[0045] FIG. 20 shows a sectional view of the operation of an
essential part illustrating an action of a second dust removing
means of the vacuum cleaner.
[0046] FIG. 21 shows a graph illustrating a relation between an
amount of collected house dust and changes in sucking airflow of
the vacuum cleaner; the relation is measured both in the vacuum
cleaner in accordance with the fifth embodiment and the vacuum
cleaner in accordance with the second embodiment for comparison
purpose.
[0047] FIG. 22 shows a perspective view of a dust collecting case
of a vacuum cleaner in accordance with a sixth embodiment of the
present invention.
[0048] FIG. 23 shows a sectional view of the operation of an
essential part illustrating an action of a third dust removing
means of the vacuum cleaner.
[0049] FIG. 24 shows a perspective view of a dust collecting case
including a third dust removing means of another vacuum cleaner in
accordance with the sixth embodiment.
[0050] FIG. 25 shows a perspective view of a dust collecting case
of a vacuum cleaner in accordance with a seventh embodiment of the
present invention.
[0051] FIG. 26 shows a sectional view of the operation of an
essential part illustrating an action of a fourth dust removing
means of the vacuum cleaner.
[0052] FIG. 27 shows a graph illustrating a relation between an
amount of collected house dust and changes in sucking airflow of
the vacuum cleaner; the relation is measured both in the vacuum
cleaner in accordance with the seventh embodiment and the vacuum
cleaner in accordance with the second embodiment for comparison
purpose.
[0053] FIG. 28 shows a perspective view of a dust collecting case
of a vacuum cleaner in accordance with an eighth embodiment of the
present invention.
[0054] FIG. 29A shows a lateral sectional view illustrating a
status where dust accumulates in the dust collecting case of the
vacuum cleaner in accordance with the eighth embodiment.
[0055] FIG. 29B shows a lateral sectional view illustrating a
status where a door of the dust collecting case opens for
discharging the accumulated dust.
[0056] FIG. 30 shows a perspective view of a dust collecting case
of a vacuum cleaner in accordance with a ninth embodiment of the
present invention.
[0057] FIG. 31A shows a lateral sectional view illustrating a
status where dust accumulates in the dust collecting case of the
vacuum cleaner in accordance with the ninth embodiment.
[0058] FIG. 31B shows a lateral sectional view illustrating a
status where a door of the dust collecting case opens for
discharging the accumulated dust.
[0059] FIG. 32A shows a lateral sectional view of a dust collecting
case in accordance with a tenth embodiment of the present
invention.
[0060] FIG. 32B shows a sectional view taken along line B-B in FIG.
32A.
[0061] FIG. 33 shows a perspective view of a dust collecting case
of the vacuum cleaner in accordance with the tenth embodiment.
DESCRIPTION OF REFERENCE MARKS
[0062] 1 cleaner unit [0063] 5 dust collecting case [0064] 6
suction port [0065] 21 electric air blower [0066] 22a upper section
of the dust collecting case [0067] 22b middle section of the dust
collecting case [0068] 23 dust separator [0069] 24 dust collector
[0070] 27 dust filter [0071] 27a first dust filter [0072] 27b
second dust filter [0073] 28 third dust filter [0074] 29a first air
duct (main air duct) [0075] 29b second air duct (sub air duct)
[0076] 31 door [0077] 33 space [0078] 41 pleated filter [0079] 42
dint [0080] 43 sealed section [0081] 51 fine dust [0082] 52 rough
dust [0083] 161 first dust removing means [0084] 191 second dust
removing means [0085] 221 third dust removing means [0086] 251
cylindrical basket (fourth dust removing means) [0087] 324 fourth
dust filter
DESCRIPTION OF PREFERRED EMBODIMENTS
[0088] A vacuum cleaner of the present invention comprises the
following elements:
[0089] an electric air blower;
[0090] a dust separator, for introducing air sucked by the air
blower and including dust, disposed on the upper stream of the
blower; and
[0091] a dust collector for accommodating the dust separated by the
dust separator, [0092] wherein the dust separator includes a
whirling airflow air-duct, which runs the air taken from a suction
port and containing the dust as the whirling airflow, and the dust
separator also includes a dust filter which forms at least a part
of the foregoing air-duct, and the dust filter is surrounded by
space on which the suction force of the air blower acts.
[0093] The foregoing structure of the present invention allows the
dust separator to generate the whirling airflow therein when the
air including the dust flows into the dust separator. The dust
having the whirling component whirls also in a hollow cylinder of
the dust separator, so that rough dust such as lint and hair whirl
and lower in the hollow cylinder and enters in the dust
collector.
[0094] The whirling airflow removes dust attaching to the inner
wall of the hollow cylinder in the dust filter, so that no dust
accumulates in the filter and thus the air-permeability of the
filter can be maintained. The sucked dust accumulates in the dust
collector, and the suction path running from the suction port to
the air blower is secured around the dust filter. As a result, this
structure does not cause to lower an air volume, but is excellent
in maintaining the air volume, so that the vacuum cleaner of the
present invention can be free from maintenance works for a long
period.
[0095] The air duct running from the suction port to the air blower
can separate the dust from the air-duct without repeating sharp
bends, expansions or shrinkages of the airflow, so that a sucking
power at a high level can be maintained for a long period. The
vacuum cleaner of the present invention thus can be free from
maintenance work for a long period while it maintains sucking power
at a high level, and its suction force is difficult to lower
although it sucks dust.
[0096] The present invention places dust filters along the entire
air-duct of the whirling airflow. This structure allows securing a
suction path running from the suction port to the air blower along
the entire dust filter, so that air volume does not decrease any
more, and the vacuum cleaner can be excellent in maintaining the
air volume and free from maintenance work for a long period.
[0097] The present invention places the dust collector under the
dust filter, so that rough dust such as lint and hair whirl in a
hollow cylinder of the dust filter and lowers to the dust collector
more efficiently.
[0098] The present invention forms the air duct of the whirling
airflow into an approx. cylindrical shape, and places a suction
port along the tangent line of this air duct. This structure allows
the air containing dust to enter into the dust separator along the
tangent line, so that more powerful whirling airflow can be
generated in the dust separator.
[0099] The present invention forms a main air duct in the space
provided to the outer circumference of the dust filters so that the
suction force of the air blower can act on the outer circumference.
This structure allows securing the suction path running from the
suction port to the air blower in a more effective manner along the
dust filters, so that the air flow does not decrease any more, and
the vacuum cleaner can be excellent in maintaining the air volume
and free from maintenance work for a long time.
[0100] The present invention provides the dust collector with a sub
air duct on which the suction force of the air blower acts. This
structure allows rough dust, which has whirled and lowered in the
hollow cylinder of the dust filter and enters in the dust
collector, to be sucked by the sub air-duct so that the rough dust
is caught and accumulated in the dust collector more positively. On
top of that, this structure can prevent the dust from reattaching
to the dust filter due to raising of dust during the operation, so
that this structure can suppress a decrease in the air volume. As a
result, a vacuum cleaner excellent in maintaining the air volume is
obtainable.
[0101] The present invention places the sub air-duct running from
the dust collector and communicating with the outside of the dust
filter via the dust filter. This structure allows the rough dust,
which whirls and lowers in the hollow cylinder of the dust filter
and enters in the dust collector, to be sucked by the sub air-duct
and to be screened out by the dust filter, so that the rough dust
can be caught by the dust collector in a more positive way before
accumulating in the dust collector. The vacuum cleaner thus can
maintain its air volume and can be free from maintenance work for a
long period.
[0102] The present invention provides the vacuum cleaner with a
third dust filter in the sub air duct. This structure allows the
rough dust, which whirls and lowers in the hollow cylinder within
the dust filter and enters in the dust collector, to be sucked
toward the third dust filter which screens out the rough dust. The
dust is thus caught in the dust collector in a more positive way
before accumulating in the dust collector. Fine dust passing
through the third filter is also screened out by the filter so that
the fine dust can be removed in the air duct on the way to the air
blower.
[0103] This structure allows separating the rough dust from the
fine dust more positively, and the rough dust can be positively
caught and accumulated in the dust collector. The vacuum cleaner
thus can maintain the air volume more positively and needs no
maintenance work for a long period.
[0104] The dust filter of the vacuum cleaner of the present
invention is formed of at least a first dust filter for collecting
rough dust on the upper stream side of the sucking airflow, and a
second dust filter placed on the outer circumference of the first
dust filter and on the down stream side for collecting fine dust.
This structure allows the first dust filter placed on the upper
stream side to collect rough dust such as lint, hair, and food
grounds, and allows the second dust filter placed on the down
stream side to collect fine dust such as grains of sand. Lint
tending to block the air duct can be thus caught on the upper
stream side and whirled in the dust collector. A decrease in
suction force can be thus prevented more effectively.
[0105] The present invention provides the dust collector with the
sub air duct on which the suction force of the air blower acts.
This structure allows the rough dust arrived at the dust collector
to be sucked by the sub air duct and screened out by the dust
filter, so that the rough dust can be caught and accumulated in the
dust collector more positively. The vacuum cleaner thus can
maintain the air volume and needs no maintenance work for a long
period. On top of that, this structure can prevent the dust from
reattaching to the dust filter due to raising of dust during the
operation, so that this structure can suppress the decrease in the
air volume. As a result, a vacuum cleaner excellent in maintaining
the air volume is obtainable.
[0106] The present invention provides the vacuum cleaner with a
main air duct running from the air duct of the whirling airflow to
the outer circumference of the dust separator via the first and the
second dust filters, and a sub air duct running from the dust
collector to the outer circumference of the dust separator via the
third and the second dust filters. This structure allows the rough
dust such as lint and hair to whirl and lower in the hollow
cylinder within the first dust filter before arriving at the dust
collector, and then allows the rough dust to be sucked from the
dust collector toward the third filter which screens out the rough
dust. The rough dust is thus caught and accumulated in the dust
collector more positively. Fine dust passing through the third
filter flows into the second filter at its lower end, and screened
out by the second filter and runs through the air duct and removed
on the way to the air blower.
[0107] This structure allows separating the rough dust from the
fine dust more positively, and the rough dust can be caught and
accumulated in the dust collector. The vacuum cleaner thus can
maintain the air volume more positively and needs no maintenance
work for a long period.
[0108] The present invention provides the vacuum cleaner with the
third dust filter for collecting rough dust. This structure allows
the rough dust entered in the dust collector to be sucked toward
the second filter through the third filter; however, the third
filter blocks the rough dust such as lint and hair to pass, so that
the rough dust is separated from fine dust. The rough dust such as
lint and hair blocking the air duct can be thus positively caught
in the dust collector, so that the decrease in the air volume can
be prevented more positively.
[0109] The present invention provides the first dust filter is made
of the material including at least one of punching metal, metal
mesh and resin mesh. This structure allows fiber-oriented dust such
as lint to resist tangling with the first filter because the first
filter has no fine peaks and valleys on the surface so that its
surface is more flat than that of a net-like dust filter, and
allows the fiber-oriented dust to whirl continuously with ease for
being caught and accumulated in the dust collector.
[0110] The present invention provides the second dust filter is
formed into a cylindrical shape formed by rounding a pleated
member. Use of the pleated member allows increasing an area of the
filter, so that resistance against air permeability can be lowered
and sucking power can be maintained at a high level for a long
period.
[0111] The present invention provides the second dust filter is
formed of the pleated member of which inner wall shapes like a
letter U rounded and forming dints at the outer circumference of
the cylindrical shape of the second filter. The rounded dints
prevent fine dust from attaching to and accumulating on the second
dust filter. The fine dust attaching to the filter can be removed
with ease, so that the decrease in the air volume can be
prevented.
[0112] The present invention provides the vacuum cleaner with a
rotary dust filter. This structure allows preventing the dust from
attaching to the filter in somewhat unbalanced manner, so that the
dust can be attached to the filter evenly in amount. As a result,
the decrease in the air volume due to clogging of the filter can be
effectively prevented.
[0113] The present invention provides the vacuum cleaner with the
first and the second dust filters at least one of which can rotate.
This structure allows preventing the dust from attaching to the
first or the second filter in somewhat unbalanced manner, so that
the dust can be attached to the filters evenly in amount. As a
result, the decrease in the air volume due to clogging of one of
the filters can be more effectively prevented.
[0114] The present invention provides the vacuum cleaner with the
first and the second dust filter both of which rotate together.
This structure allows preventing the dust from attaching to the
first and the second filters in somewhat unbalanced manner, so that
the dust can be attached to the filters evenly in amount. As a
result, the decrease in the air volume due to clogging of the
filters can be more effectively prevented with a simple
structure.
[0115] The present invention provides the vacuum cleaner with a
dust removing means for removing the dust attaching to the dust
filter. This structure allows removing fine dust such as grains of
sand attaching to the filter, so that the clogging of the filter
can be more positively prevented, and the decrease in the air
volume can be prevented.
[0116] The present invention prepares a dust removing means
contacting with the rotary dust filter. This structure allows
removing the dust attaching to the inner wall of the dust filter
along the entire circumference. This removing means can be manually
rotated with a simple structure, or the removing means includes a
rotary driving means and a control means for rotating the dust
removing means in step with the timing of the air blower. As a
result, the air permeability of the dust filter can be maintained
more effectively, so that the decrease in the air volume can be
prevented.
[0117] The present invention provides at least one of the first or
the second rotary dust filter with a dust removing means contacting
thereto for vibrating the filter contacting to the removing means,
so that the dust attaching to the filter can be removed. This
structure allows removing the dust attaching to the inner wall of
the first or the second dust filter more effectively. As a result,
the decrease in the air volume can be prevented more
effectively.
[0118] The present invention provides at least one of the first or
the second rotary dust filter with a dust removing means contacting
thereto for scraping or rubbing off the dust attaching to the dust
filter. This structure allows removing the dust attaching to the
inner wall of the first or the second dust filter more effectively,
which dust is lint or hair tangling with the filter or causes
clogging.
[0119] The present invention provides the vacuum cleaner with a
dust removing means that moves along the dust filter while it
contacts with the filter, thereby vibrating the filter for removing
the dust or scraping or rubbing off the dust attaching to the
filter. This structure allows removing the dust attaching to the
inner wall of the filter with ease along the entire circumference.
This removing means can be manually rotated with a simple
structure, or the removing means includes a rotary driving means
and a control means for rotating the dust removing means in step
with the timing of the air blower. As a result, the air
permeability of the dust filter can be maintained more effectively,
so that the decrease in the air volume can be prevented.
[0120] The third dust filter of the present invention shapes like a
truncated cone, i.e. the lower diameter is greater than the upper
diameter, and both of the upper and lower ends open. This structure
allows the fine dust removed from the third dust filter to drop
into the dust collector under the third filter along the slanting
face formed of bus lines. The fine dust can be prevented from
reattaching to the third filter, so that the decrease in the air
volume can be prevented more effectively.
[0121] The dust filter of the present invention shapes like a
truncated cone, i.e. the lower diameter is greater than the upper
diameter. This structure allows sucking the dust of a greater
amount than a capacity of the dust collector. If the dust of a
greater amount than a capacity of the dust collector is sucked and
the dust clogs in the hollow cylinder within the dust filter, the
dust can be removed from the filter with ease because the lower
section is greater than the upper section. The vacuum cleaner
excellent in throwing the dust away and convenience is thus
obtainable.
[0122] The present invention provides the third dust filter with an
opening and places a dust removing means near to this opening. A
dust chamber communicating with this opening is provided in the
dust collector. The dust removed by the dust removing means runs
through this opening and is accommodated in this chamber. This
structure can prevent the dust from reattaching to the dust filter
due to raising of dust during the operation, so that this structure
can further suppress the decrease of the air volume. As a result, a
vacuum cleaner excellent in maintaining the air volume is
obtainable.
[0123] The present invention prepares vent holes on a lateral wall
of the dust chamber for communicating with the dust collector, and
a fourth dust filter is placed on the vent holes. This structure
secure the air duct running from the dust collector to the outer
circumference of the dust filter via the fourth filter and the dust
chamber, so that a sucking air volume is difficult to lower even
the vacuum cleaner sucks dust, and the sucking power can be kept at
a high level for a long period.
[0124] The present invention discharges the dust by opening the
bottom of the dust collector. This structure allows the fine and
rough dust accumulated in the dust collector to drop by means of
gravity, so that the dust in the collector can be discharged with
ease. The vacuum cleaner excellent in throwing the dust away and
convenience is thus obtainable.
[0125] The present invention forms at least one of the dust
separator or the dust collector at least in part by using
see-through material. This structure allows the user to see the
dust whirling or recognize an amount of the dust collected, so that
the users can determine the timing of throwing the dust away from
the dust collector or find abnormality in the dust collector
sooner.
[0126] The present invention forms the dust filter at least in part
by using see-through material. This structure allows the users to
see the content of the dust, so that the users can find some thing
other than dust with ease.
[0127] The structure of the vacuum cleaner of the present invention
is described more specifically hereinafter. The vacuum cleaner
comprises the following elements:
[0128] a sucking tool for sucking dust scattered on the floor;
[0129] an electric air blower for sucking the air transferred from
the sucking tool and containing the dust;
[0130] a cleaner unit accommodating the air blower;
[0131] a dust separator for taking the air in sucked by the air
blower and containing the dust, and separating the dust from the
air; and
[0132] a dust collector for collecting the dust separated from the
air.
[0133] The dust separator includes a suction port for taking the
air in transferred from the sucking tool and containing the dust,
an air duct for running the air containing the dust as whirling
airflow, and a dust filter for separating the dust from the air and
forming at least a part of the air duct. A main air duct covers the
outer circumference of the dust filter and is coupled to the
suction side of the air blower so that the suction force of the air
blower can act on the outer circumference of the dust filter.
[0134] Generation of the whirling airflow needs the following
structure: the air duct for the whirling airflow shapes like an
approx. cylinder, more preferably, it forms a cylinder, and a
suction port is formed such that the whirling airflow is generated
along the inner wall of the air duct and the air flow whirls along
the circumference direction. To be more specific, the sucking
direction of the suction port crosses the axial direction of the
cylinder at right angles so that it can run along the
circumferential direction of the inner wall, and the sucking
direction runs along the tangent line of the cylinder. The approx.
cylindrical shape includes a sectional view of an oval or polygon
such as an octagon. Any shape is acceptable as far as it allows
generating the whirling airflow along the circumferential direction
of the inner wall of the air duct.
[0135] The generation of the whirling airflow in the air duct
naturally needs a negative pressure status produced by the suction
force of the air blower acting on the inside of the air duct. For
that purpose, a first end having the suction port of the air duct
is covered with the top face of the dust collector and a second end
thereof is air-tightly coupled to the dust collector, so that the
suction force of the air blower acts on the dust filter formed in
the air duct.
[0136] More preferably, a sub air duct is placed to the coupling
section between the air duct and the dust collector or to the dust
collector per se, so that the suction force of the air blower acts
on the sub air duct. This structure allows obtaining not only the
suction force acting on the dust filter but also the suction force
acting on somewhere near the dust collector, so that the dust
passing through the dust filter moves to the dust collector with
more ease.
[0137] A first end of the sub air duct is coupled to a part of the
dust collector, and a second end thereof is coupled to the suction
side of the air blower or to a part of the main air duct already
formed. This structure produces a similar advantage to what is
discussed previously. Preferably the third dust filter is mounted
to the first end of the sub air duct for preventing the dust
accumulated in the dust collector from flowing to the air blower.
It is preferable to prepare the third dust collector not ready to
be clogged, particularly when the suction force of the air blower
desirably acts on the dust collector via the sub air duct.
[0138] Therefore, the third dust filter is used for collecting
rough dust, so that it is difficult to be clogged and it can be
used for a long period. Use of the third filter for collecting the
rough dust possibly prompts fine dust to flow into the sub air
duct. If the fine dust flows into the air blower directly, the air
blower lowers its durability. When the third filter is used for
collecting the rough dust, a fine-dust filter should be placed on
the upper stream of the suction side of the air blower.
[0139] If the dust filter placed in the main air duct is used for
collecting the fine dust, the sub air duct can be coupled to the
main air duct placed on the upper stream of the fine dust filter.
This coupling method allows the fine dust filter to collect the
fine dust from the sub air duct, and this method also can eliminate
a fine dust filter exclusively used in the sub air duct, so that
the maintenance work of the fine dust filter can be improved.
[0140] The foregoing vacuum cleaner invites self-cleansing effect
at the dust filter placed in the dust separator due to the whirling
airflow; however, since the dust filter is sucked from its outer
circumference, the clogging with the dust cannot be eliminated
100%. The dust removing means is thus prepared for removing the
dust clogged in the filter. This dust removing means is operated
at, e.g. starting or ending the operation of the vacuum cleaner for
removing the dust clogged in the filter. This operation allows the
vacuum cleaner to be used for a long period free from lowering the
suction force and sucking power.
[0141] The timing of working the dust removing means is preferably
set in accordance with the structure of the dust separator, a type
of dust filters to be used after studying how much clogging is
generated in the dust filter during actual cleaning operations. To
be more specific, the dust removing means is operated for a given
time when the vacuum cleaner starts working, or when the vacuum
cleaner ends working, or operated for a given time both at the
start and the end of the work of the cleaner. It is preferable to
use a motor to drive the dust removing means at the foregoing
timing.
[0142] For instance, on-off control over a motor can be done with
ease by a microprocessor, and this control can be incorporated
easily into the control program (carried out in general by a
microprocessor) over the vacuum cleaner as a part of sequential
actions. Use of a cord take-up mechanism built in the vacuum
cleaner for controlling the dust removing means is another way than
the use of the motor as discussed above. To be more specific, a
user pulls the cord wound on the take-up mechanism for starting the
cleaning, then the cord wound section of the mechanism is rotated
by the pulling force. If this rotating force is transferred to the
dust removing means, the removing means works when the cleaner
starts working. In general, the take-up mechanism includes a
built-in spring, which is wound by the rotation of the take-up
mechanism when the cord is pulled. At the end of cleaning, a button
(in general, the button is placed at a part of the cleaner unit to
be depressed) is pushed for taking up the cord on the mechanism,
and then the wound spring rotates the take-up section along the
take-up direction. If this rotating force is transferred to the
dust removing means, the removing means can work at the end of
cleaning.
[0143] As discussed above, a method of working the dust removing
means can be selected appropriately; however, the operation of the
dust removing means at least every time when the cleaning starts
and ends allows removing the clogging in the dust filter whenever
the cleaner starts working. The vacuum cleaner thus can maintain
and exert the original suction force and sucking power whenever it
works. The vacuum cleaner of the present invention has a structure
where the suction force acts on the outer circumference of the dust
filter, namely, self cleansing action can suppress the clogging in
the dust filter, and yet, the dust removing means is employed in
the foregoing structure, so that no clogging occurs over a long
time-span, and this structure allows the vacuum cleaner to be free
from maintenance work over a long time-span. The operation time of
the dust removing means can be shortened because the foregoing
clog-resistant structure. In the case of driving the dust removing
means by a motor, this structure does not take a time for a user to
start cleaning or to restore the tools and parts to the original
places, so that the user can simply use the cleaner in an efficient
manner.
[0144] Exemplary embodiments of the present invention are described
hereinafter.
Embodiment 1
[0145] FIG. 1 and FIG. 2 show a vacuum cleaner in accordance with
the first exemplary embodiment. As shown in FIG. 2, cleaner unit 1
includes electric air blower 21, and both of wheels 3 and casters 4
are mounted to the outside of cleaner unit 1 for moving freely on
the floor. Dust collecting case 5 is mounted to cleaner unit 1 in a
detachable manner on the upper stream side of electric air blower
21 via air-permeable partition wall 26. Dust collecting case 5
takes the air in sucked by electric air blower 21 and including
dust.
[0146] Dust collecting case 5 is formed by piling up a plurality of
hollow cylinders having different diameters from each other. In
this first embodiment, three cylinders are piled up from the top in
this order; upper section 22a of case 5, middle section 22b of case
5, and dust collector 24. Upper section 22a and middle section 22b
of case 5 work as dust separator 23. Upper section 22a includes
suction port 6 which takes the air in including dust along the
tangent line.
[0147] Dust collecting case 5 communicates from suction port 6 to
dust collector 24 on the bottom where dust accumulates, and the air
duct running from suction port 6 to electric air blower 21
communicates with partition wall 26 of cleaner unit 1 at opening 25
placed at dust separator 23 in dust collecting case 5. Cylindrical
dust filter 27 is placed in dust separator 23.
[0148] As shown in FIG. 1, suction port 6 is coupled to suction
hose 7 and extension tube 8 in this order, and sucking tool 9 is
mounted to the tip of extension tube 8. Driving electric air blower
21 will suck the dust on the floor.
[0149] Cylindrical dust filter 27 is formed of two layers, namely,
cylindrical first dust filter 27a placed on the upper stream side
and forming a rough-dust filter, and cylindrical second dust filter
27b placed on the down stream side of the first dust filter 27a at
the outer circumference and forming a fine dust filter. Air vents
of first dust filter 27a and second dust filter 27b are placed in
the middle of main air duct 29a, i.e. a first air duct, through
which suction port 6 communicates with electric air blower 21.
[0150] Main air duct 29a running from suction port 6 to electric
air blower 21 is placed along the entire circumference of the air
space stretching from the inside of first dust filter 27a to the
outer circumference of second dust filter 27b.
[0151] Dust collecting case 5 and cylindrical dust filter 27 are
detailed hereinafter with reference to FIGS. 3A, 3B, 3C and 3D. As
shown in FIG. 3A, case 5 is formed by piling up three vertical and
hollow cylinders. Suction port 6 is placed as shown in FIG. 3C at
an off-center place such that the airflow flows thereto along the
tangent line on the sectional view of circle of upper section 22a
of case 5. In this first embodiment, dust collecting case 5 shapes
like a hollow cylinder; however, the cross section of the cylinder
is not necessarily a true round, but it can be an oval, or a
polygon such as an octagon or a decagon. Any shape can be
acceptable as far as it allows the airflow, which enters along the
tangent line of suction port 6, to whirl along the inner wall of
case 5. Cylindrical dust filter 27 is also not necessarily a true
round, but it can be an oval, or a polygon such as an octagon or a
decagon. Any shape can be accepted as far as it allows the whirling
airflow generated along the inner wall of case 5 to be generated
also in the hollow cylinder of first dust filter 27a.
[0152] The path, which forms the whirling airflow generated along
the inner wall of upper section 22a of case 5 as well as forms the
whirling airflow generated in the hollow cylinder of first dust
filter 27a, is thus referred to as a whirling airflow air-duct.
[0153] Suction port 6 is placed at upper section 22a of case 5 such
that the whirling airflow can be generated along the direction
toward dust collector 24, to be more specific, the lower end of
suction port 6 is placed over the upper end of opening 25 provided
to dust separator 23. This structure allows the air taken into
suction port 6 along the tangent direction of upper section 22a to
be whirled toward dust collector 24, i.e. along the downward
direction, due to suction force acting on opening 25. The whirling
airflow lowering and whirling involves rough dust 52 such as lint
in whirling and lowering to dust collector 24 because rough dust 52
receives wind pressure of the whirling airflow.
[0154] Dust collecting case 5 has dust collector 24 at its bottom
for accumulating the dust, and the bottom face of case 5 works as
door 31, so that door 31 is opened via hinge 32 for discharging the
dust accumulated in dust collector 24.
[0155] Dust collecting case 5 is made of acrylic resin in this
first embodiment, and at least a part of case 5 is preferably made
of see-through material so that an amount of dust can be recognized
by human eyes with ease. The see-through material is preferably
ABS, polypropylene, or acrylic resin because they are obtainable
with ease and excellent in being processed.
[0156] As shown in FIG. 3B, on the inner wall between suction port
6 and dust collector 24, space 33 is formed over the entire outer
circumference between case 5 and cylindrical dust filter 27, so
that the interior of case 5 communicates with suction port 6 of
electric air blower 21 via this space 33.
[0157] The inner wall of upper section 22a of case 5 and the inner
wall of first dust filter 27a form one wall as a whole, in other
words, nothing protrudes on the inner wall of case 5. First dust
filter 27a is one of the elements of cylindrical filter 27 and
placed inside of filter 27. As shown in FIG. 3D, cylindrical dust
filter 27 rounds itself in cylindrical case 5 so that filter 27
forms a cylindrical shape. First dust filter 27a, i.e. a rough dust
filter, placed on the upper stream side of sucking airflow screens
out larger dust such as lint and hair from the sucking airflow.
Second dust filter 27b, i.e. a fine dust filter, placed on the down
stream side of the sucking airflow screens out smaller dust (small
particles) such as grains of sand, pollens and tick-droppings from
the airflow.
[0158] As discussed above, use of multi-layer cylindrical dust
filters in response to sizes of dusts to be screened out will
decrease the frequency of clogging in the dust filter, so that the
performance of maintaining the air volume can be extended. The
multi-layer structure can be replaced with a single-layer
structure.
[0159] First dust filter 27a is preferably made of metal mesh,
punching metal or resin mesh having a rather larger hole diameter
so that fine dust such as grains of sand can pass through. In this
first embodiment, metal mesh having vent holes of which diameter is
250 micron is used so that fine projections on the inner wall of
first dust filter 27a can be minimized.
[0160] Second dust filter 27b can be made of non-woven fabric,
pulp, glass fiber, or HEPA filter. The non-woven fabric is pleated
and then formed into a cylindrical shape because this material can
screen out rather smaller particles efficiently. The filter thus
made can reduce the vent resistance while it maintains dust
removing performance. Porous member made of PTFE excellent in
removing dust, is preferably coated on the filter face, to which
dust attaches, because use of this filter as second dust filter 27b
can suppress the clogging in the filter.
[0161] FIG. 4 shows a sectional view of an enlarged essential part
of second dust filter 27b shown in FIG. 3D. In this first
embodiment, as shown in FIG. 3D and FIG. 4, a sheet of filter made
of PTFE film, having vent holes of which diameter is approx. 0.5
micron, and reinforced by PET resin for increasing rigidity, is
used. This sheet filter is pleated to form pleated filter 41, and
both of the ends are coupled together to form a cylindrical
shape.
[0162] At the circumference of pleated filter 41, dints 42 are
formed on the inner wall of the pleated member which is located on
the upper stream side of the sucking airflow, and dints 42 shape
like letter U and are rounded with R (radius)=2-5 mm. Some part of
pleated filter 41 closer to first dust filter 27a has no dints
42.
[0163] Exterior of pleated filter 41, i.e. second dust filter 27b,
is sealed with resin or sealing agent at the upper and lower ends
in the range of several millimeters to form sealed section 43,
which blocks both of upward and downward air-permeability.
[0164] Operation of the foregoing vacuum cleaner in accordance with
the first embodiment is demonstrated hereinafter with reference to
FIGS. 5A-5C. Upon turning on electric air blower 21, sucking
airflow is generated, and air including dust scattered on the floor
is sucked into dust collecting case 5 via sucking tool 9, extension
tube 8, and sucking hose 7. Since suction port 6 of case 5 is
placed off-center toward the tangent direction on the cross section
of the cylinder, the airflow flowing into suction port 6 as shown
in FIG. 5A enters into case 5 along the tangent direction of the
cross section of the cylindrical case 5, and then changes into the
whirling airflow.
[0165] The whirling airflow generated at upper section 22a of case
5 whirls and lowers to the vicinity of cylindrical dust filter 27.
Since first dust filter 27a placed on the upper stream side has no
projections toward the interior of dust collecting case 5, nothing
blocks the flow of the whirling airflow, so that the airflow still
whirls and passes through first dust filter 27a, second dust filter
27b, and space 33 sequentially as shown in FIG. 5B, and is sucked
into electric air blower 21.
[0166] The dust sucked together with the sucking airflow whirls
with the airflow and arrives at cylindrical dust filter 27, and
fine dust 51 such as grains of sand passes through first dust
filter 27a and is filtered out by second dust filter 27b placed
outside the first one.
[0167] Rough dust 52 such as lint having a small specific gravity
and subject to wind pressure is easily removed from the surface of
first dust filter 27a, and as shown in FIG. 5B and FIG. 5C, rough
dust 52 still whirls in first dust filter 27a at the hollow
cylinder. This operation proves that first dust filter 27a exerts
self-cleansing function by using the airflow, so that no clogging
is invited and a decrease in the suction force can be
suppressed.
[0168] As an amount of dust sucked increases, rough dust 52 such as
lint whirls in first dust filter 27a and lowers to dust collector
24. To summarize what is discussed above, rough dust 52 such as
lint receives wind pressure from the whirling airflow, and then
whirls and lowers to dust collector 24, and fine dust 51 such as
grains of sand passes through mesh holes of first dust filter 27a,
so that no dust accumulates in first dust filter 27a, which can be
thus free from clogging and maintain its air permeability.
[0169] To be more specific, dust sucked is positively separated
into fine dust 51 and rough dust 52, and fine dust 51 is filtered
out by second dust filter 27b, and rough dust 52 is caught by dust
collector 24. Suction path running from suction port 6 to electric
air blower 21 is secured along the circumference of first and
second dust filters 27a and 27b, so that a decrease in air volume
can be suppressed.
[0170] On top of that, second dust filter 27b includes dints 42 at
its pleated section located on the upper stream side of the sucking
airflow, and each one of the dints 42 shapes like letter U and is
rounded with 2 R-5 R. This rounded dint prevents fine dust 51 from
attaching to and accumulating on second dust filter 27b. Even if
fine dust 51 accumulates, this structure allows removing fine dust
51 with ease, so that the decrease in air volume due to clogging in
the filter can be prevented.
[0171] Although an amount of dust accumulated in dust collecting
case 5 increases, door 31 is opened for discharging the dust
smoothly because no projections exist in the interior of case 5,
which can be thus taken care very easily.
[0172] Performance of maintaining the air volume is evaluated on
the vacuum cleaner in accordance with the first embodiment. House
dust is separated into lint and fine dust by using a sieve, and 4 g
of lint and 3 g of fine dust are mixed together, so that total 7 g
is sucked per operation for evaluating a change in the air volume.
FIG. 6 shows the evaluation result. A cyclone vacuum cleaner
commercially available is also evaluated for comparison
purpose.
[0173] As shown in FIG. 6, the vacuum cleaner of the first
embodiment maintains an air volume at a high level from the start,
and it maintains over 90% of the initial air volume after sucking
80 g of dust; however, the cyclone vacuum cleaner shows a low air
volume at the start, and decreases the air volume at a high speed,
then it only keeps not more than 80% of the initial air volume
after sucking 60 g of dust. On top of that, sucking power of the
two cleaners are measured, and the cleaner of the first embodiment
shows the sucking power higher than the cyclone cleaner by over 100
W.
[0174] This evaluation proves that the vacuum cleaner in accordance
with the first embodiment maintains the sucking power at a high
level, and resists against the decrease in suction force while it
sucks dust.
[0175] In this first embodiment, second dust filter 27b is placed
along the entire outer circumference of first dust filter 27a;
however, as shown in FIGS. 7, 8A and 8B, second dust filter 27b is
not necessarily placed along the entire circumference, and it can
be placed simply on the suction side of the air blower. This simple
structure produces an advantage similar to what is discussed
above.
[0176] As shown in FIG. 9A with broken lines and in FIG. 9B,
cylindrical dust filter 27 is notched, and see-through and
arc-shaped material is fit into this notch to form see-through
window 91, which allows a user to monitor accumulated dust
vertically in a sectional view. The user thus can easily find some
item erroneously sucked out of the dust.
Embodiment 2
[0177] In this second embodiment, differences in structure and
operation from those of the first embodiment are discussed, and
elements similar to those used in the first embodiment have the
same reference marks and the descriptions thereof are omitted here.
FIGS. 10, 11A, 11B, 11C and 11D show a vacuum cleaner in accordance
with the second embodiment and sectional views of dust collecting
case 5.
[0178] As shown in these Figs., the vacuum cleaner in accordance
with the second embodiment differs from that of the first
embodiment in third dust filter 28 shaped like a cylinder placed
beneath cylindrical dust filter 27. This third dust filter 28 is
formed of a rough dust filter which is made of metal mesh of which
vent hole is 250 micron across. This structure is similar to first
dust filter 27a. An inner end of third dust filter 28 solidly
contacts (without any gaps) with the rim end of first dust filter
27a, and an outer end of third dust filter 28 solidly contacts with
sealed section 43 and dust collector 24 such that third dust filter
28 can cover over sealed section 43 at the lower end of the outer
circumference of second dust filter 27b.
[0179] Third dust filter 28 is placed at some place in sub air-duct
29b, i.e. a second air-duct, running from suction port 6 to the
lower end of second dust filter 27b via the hollow cylinder of
first dust filter 27a, dust collector 24 and this third dust filter
28. First dust filter 27a, second dust filter 27b and third dust
filter 28 are thus placed in main air-duct 29a, through which
suction port 6 communicates with electric air blower 21, or sub
air-duct 29b. Operation of the foregoing vacuum cleaner is
demonstrated hereinafter with reference to FIGS. 12A-12C.
[0180] Upon starting the operation of electric air blower 21,
sucking airflow is generated, and dust scattered on the floor is
sucked into dust collecting case 5 via sucking tool 9, extension
tube 8, and sucking hose 7. Since suction port 6 of case 5 is
placed off-center toward the tangent direction on the cross section
of the cylinder, as shown in FIG. 12A, the airflow flowing in
suction port 6 enters in case 5 along the tangent direction of the
cross section of the cylinder, and changes to the whirling
airflow.
[0181] The whirling airflow generated at upper section 22a of case
5 whirls and lowers to the vicinity of cylindrical dust filter 27.
Since first dust filter 27a placed on the upper stream side has no
projections toward the interior of dust collecting case 5, nothing
blocks the flow of the whirling airflow, so that the airflow still
whirls and passes through first dust filter 27a, second dust filter
27b, and space 33 sequentially as shown in FIG. 12B, and is sucked
into electric air blower 21.
[0182] The dust sucked together with the sucking airflow whirls
with the airflow and arrives at cylindrical dust filter 27, and
fine dust 51 such as grains of sand passes through first dust
filter 27a and is filtered out by second dust filter 27b placed
outside the first dust filter 27a.
[0183] Rough dust 52 such as lint having a small specific gravity
and subject to wind pressure is easily removed from the surface of
first dust filter 27a, and as shown in FIG. 12B and FIG. 12C, rough
dust 52 still whirls in first dust filter 27a at the hollow
cylinder. This operation proves that first dust filter 27a exerts
self-cleansing function by using the airflow, so that no clogging
is invited and a decrease in the suction force can be
suppressed.
[0184] As an amount of dust sucked increases, rough dust 52 such as
lint whirls in first dust filter 27a and lowers to dust collector
24. Rough dust 52 arrived at dust collector 24 is sucked toward
dints 42 of pleated section at the end of second dust filter 27b
via third dust filter 28 placed over dust collector 24, so that
rough dust 52 can be caught and accumulated positively in dust
collector 24. On top of that, compression acts on rough dust 52, so
that shrinkage in a volume of rough dust 52 can be expected.
[0185] Without sub air-duct 29b, when the suction path is blocked
on the upper stream side of dust collecting case 5, almost all the
dust in dust collector 24 is raised cloudily and reattaches to the
inner wall of first dust filter 27a. Sub air-duct 29b communicates
with main air-duct 29a via dust collector 24 when the sucking path
is blocked on the upper stream side, and sub air-duct 29b thus
becomes a bypath which can prevent, in advance, the dust from being
raised cloudily.
[0186] In first dust filter 27a, rough dust 52 such as lint
receives wind pressure from the whirling airflow, and then whirls
and lowers, and fine dust 51 such as grains of sand passes through
mesh holes of first dust filter 27a, so that no dust accumulates in
first dust filter 27a, which can be thus free from accumulation of
dust, and maintain its air permeability.
[0187] Third dust filter 28 is made of metal mesh, and placed such
that its inner end solidly contact (without any gaps) with the rim
end of first dust filter 27a, and its outer end solidly contacts
with sealed section 43 provided to the outer circumference on the
lower end of second dust filter 27b. This structure allows fine
dust 51 mixed with rough dust 52 in dust collector 24 to pass
through third dust filter 28, and then rough dust 52 is filtered
out by second dust filter 27b.
[0188] To be more specific, dust sucked is positively separated
into fine dust 51 and rough dust 52, and fine dust 51 is filtered
out by second dust filter 27b, and rough dust 52 is caught in dust
collector 24. The suction path running from suction port 6 to
electric air blower 21 is secured along the circumference of first
and second dust filters 27a and 27b, so that a decrease in air
volume can be suppressed.
[0189] In this second embodiment, an evaluation test is carried out
on the performance of maintaining the air volume as it is done in
the first embodiment. FIG. 13 shows the test result, which tells
that the second embodiment shows better performance than the first
embodiment.
[0190] Use of third dust filter 28 placed in dust collecting case 5
in addition to the structure of the first embodiment allows dust
collector 24 to catch and accumulate the rough dust therein
positively, so that the decrease in air volume can be more
positively suppressed. As a result, a useful vacuum cleaner is
obtainable.
[0191] In this second embodiment, second dust filter 27b and third
dust filter 28 are placed along the entire circumference of first
dust filter 27a; however, similar to the first embodiment, they can
be placed simply on the suction side of the air blower (not shown).
This simple structure produces a similar advantage to what is
discussed above.
Embodiment 3
[0192] In this third embodiment, differences in structure and
operation from those of the first and second embodiments are
discussed, and elements similar to those used in the first and
second embodiments have the same reference marks and the
descriptions thereof are omitted here.
[0193] FIG. 14 shows a sectional plan view of an essential part of
cylindrical dust filter 27. Other structures remain as they are in
the second embodiment. As shown in FIG. 14, driving gear 141 is
placed to sealed section 43 at the upper end of outer circumference
of second dust filter 27b. Second dust filter 27b and first dust
filter 27a are rotated together by this driving gear 141 and
another driving gear 142 engaging with driving gear 141, and motor
143 which drives gear 142.
[0194] Both of first and second dust filters 27a, 27b can be
rotated as discussed above; however, only second dust filter 27b
can be rotated, or first dust filter 27a is provided with driving
gear 141, and then first dust filter 27a can be driven alone by
driving gear 142 and motor 143.
[0195] Rotation of first and second dust filters 27a, 27b driven by
motor 143 allows preventing dust from attaching to the filters at
some parts in unbalanced manner, because the dust tends to attach
to around partition wall 26 on which suction force of air blower 2
acts more strongly. The foregoing structure thus can prevent this
problem, and make an amount of dust attaching to the first and
second dust filters 27a, 27b uniform quantity-wise, so that a
decrease in air volume due to clogging in the filter can be
prevented more positively.
[0196] Performance of maintaining the air volume is evaluated on
the vacuum cleaner in accordance with the third embodiment. House
dust is separated into lint and fine dust by using a sieve, and 4 g
of lint and 3 g of fine dust are mixed together, so that total 7 g
is sucked per operation for evaluating a change in the air volume.
FIG. 15 shows the evaluation result, which tells that this third
embodiment is more excellent in the performance of maintaining air
volume than the second embodiment.
[0197] This evaluation proves that the vacuum cleaner in accordance
with the third embodiment maintains the sucking power at a high
level, and resists against the decrease in suction force while it
sucks dust. In this third embodiment, second dust filter 27b and
third dust filter 28 are placed along the entire circumference of
first dust filter 27a; however, similar to the previous
embodiments, they can be placed simply on the suction side of the
air blower (not shown). This simple structure produces a similar
advantage to what is discussed previously.
Embodiment 4
[0198] In this fourth embodiment, differences in structure and
operation from those of embodiments 1-3 are discussed, and elements
similar to those used in the previous embodiments have the same
reference marks and the descriptions thereof are omitted here.
[0199] FIGS. 16A, 16B and 17 show sectional views of dust
collecting case 5 in accordance with the fourth embodiment and
essential parts of dust collecting case 5. In FIGS. 16A and 16B,
first dust removing means 161 is rigidly mounted to at least one of
an upper section or a lower section of dust collecting case 5. As
shown in FIG. 17, first dust removing means 161 shapes like a
spatula, of which both ends are sharpened, and is urged against the
inner wall of first dust filter 27a.
[0200] As already described in embodiment 3, motor 143 and driving
gear 142 rotate driving gear 141 placed on second dust filter 27b,
so that first dust filter 27a and second dust filter 27b are
rotated together, then first dust removing means 161 slides on the
inner wall of first dust filter 27a while it is urged against the
inner wall. First dust removing means 161 thus cleans the inner
wall of first dust filter 27a by removing the dust such as lint
attaching to or accumulating on the inner wall of first dust filter
27a, thereby maintaining the air permeability of first dust filter
27a and preventing a decrease in air volume.
[0201] First dust filter 27a is set such that it rotates one turn
for 5 seconds, and motor 143 is powered for 5 seconds by a
controller (not shown) just after electric air blower 21 is
stopped, so that both of second and first dust filters 27b, 27a
rotate together. In this instance, only one dust removing means 161
is employed; however, a plurality of the dust removing means will
produce the greater advantage.
[0202] First dust removing means 161 shaping like a spatula is
employed in this fourth embodiment; however, the shape can be
changed to a brush-like or raising-like shape depending on types of
the dust for obtaining proper effect to the shape.
[0203] In this embodiment, as shown in FIG. 16A, a bar-like member
is mounted vertically to an upper section of dust collecting case 5
as first dust removing means 161; however, as shown in FIG. 18,
first dust removing means 161 can be mounted spirally with an angle
while it is urged against the inner wall of first dust filter 27a.
This structure increases shearing effect when first filter 27a is
rotated, so that hair or lint tangled is sheared during the
cleaning, and the better cleaning effect can be expected.
Embodiment 5
[0204] In this fifth embodiment, differences in structure and
operation from those of embodiments 1-4 are discussed, and elements
similar to those used in the previous embodiments have the same
reference marks and the descriptions thereof are omitted here.
[0205] FIGS. 19A and 19B show sectional views of a vacuum cleaner
in accordance with the fifth embodiment. FIG. 19A shows a vertical
sectional view of the vacuum cleaner. In FIG. 19A, second dust
removing means 191 is placed around the outside of second dust
filter 27b. FIG. 20 shows an enlarged essential part of second dust
removing means 191, which includes a spring formed by bending metal
foil. The spring works as beater 201.
[0206] Driving gear 141 is coupled to second dust filter 27b, and
first filter 27a moves together with second dust filter 27b.
Driving gear 141 is driven by motor 143 and driving gear 142,
thereby driving first and second dust filters 27a, 27b.
[0207] As shown in FIGS. 19B and 20, rotation of first and second
dust filters 27a, 27b will prompt beater 201 to beat second dust
filter 27b from the outside, thereby dropping the dust attaching to
or accumulating on the inside of pleated filter 41, which shapes
like letter U, of second dust filter 27b, so that second dust
filter 27b can be cleaned. Continuous rotation of filters 27a and
27b will clean the entire circumference of filter 27b.
[0208] In this embodiment, second dust filter 27b is set such that
it rotates one turn in 5 seconds, and motor 143 is powered for 5
seconds by a controller (not shown) just after electric air blower
21 is stopped, so that second and first dust filters 27b, 27a
rotate together. After electric air blower 21 is halted, second
dust filter 27b can be thus cleaned for 5 seconds, thereby dropping
the dust attaching to the entire circumference of second dust
filter 27b.
[0209] The same evaluation test as the first embodiment is done on
the performance of maintaining the air volume, and the result is
shown in FIG. 21, which tells that the fifth embodiment is more
excellent in this performance than the second embodiment.
[0210] As discussed above, the rotation of first and second dust
filters 27a, 27b prompts second dust removing means 191 to remove
the dust attaching to second dust filter 27b for cleaning. As a
result, the decrease in air volume can be prevented more
positively.
[0211] Beater 201 formed by bending metal foil is used as second
dust removing means 191 in this fifth embodiment; however, beater
201 can be a plate-like member or an elastic member such as
rubber.
Embodiment 6
[0212] In this sixth embodiment, differences in structure and
operation from those of embodiments 1-5 are discussed, and elements
similar to those used in the previous embodiments have the same
reference marks and the descriptions thereof are omitted here.
[0213] FIG. 22 shows a perspective view of dust collecting case 5
of the vacuum cleaner in accordance with the sixth embodiment. In
FIG. 22, third dust removing means 221 is rigidly mounted to upper
section 22a of case 5, and upper section 22a rotates together with
middle section 22b while they maintain air-tightness in
between.
[0214] Third dust removing means 221 shapes like a spatula, of
which both ends are sharpened, and is urged against the inner wall
of first dust filter 27a, as shown in FIG. 23.
[0215] Rotation of upper section 22a will prompt third dust
removing means 221 to slide on the inner wall of first dust filter
27a while third dust removing means 221 is urged against the inner
wall, thereby cleaning the inner wall of filter 27a. The dust such
as lint tangling in and attaching to the inner wall of first filter
27a thus can be removed. This structure allows maintaining the air
permeability of filter 27a and preventing a decrease in air volume.
In this instance, only one third dust removing means 221 is
employed; however, a plurality of third dust removing means 221
will produce the greater advantage.
[0216] Third dust removing means 221 shaping like a spatula is
employed in this sixth embodiment; however, the shape can be
changed to a brush-like or raising-like shape depending on types of
the dust for obtaining proper effect to the shape.
[0217] Third dust removing means 221 is mounted vertically;
however, as shown in FIG. 24, it can be mounted spirally with an
angle. This structure increases shearing effect when third dust
removing means 221 is rotated, so that hair or lint tangled is
sheared during the cleaning, and the better cleaning effect can be
expected.
[0218] Third dust removing means 221 fixed to upper section 22a of
case 5 can be rotated manually along either direction, and this
method makes the structure simple, or it can be rotated by a driver
and a controller (neither one not shown) such that it rotates in
step with the timing when electric air blower 21 starts or
stops.
Embodiment 7
[0219] In this seventh embodiment, differences in structure and
operation from those of embodiments 1-6 are discussed, and elements
similar to those used in the previous embodiments have the same
reference marks and the descriptions thereof are omitted here.
[0220] FIG. 25 shows a perspective view of dust collecting case 5
of the vacuum cleaner in accordance with the seventh embodiment.
FIG. 26 shows a sectional view of an essential part of a fourth
dust removing means (cylindrical basket 251) of the vacuum cleaner.
FIG. 25 illustrates that the fourth dust removing means, i.e.
cylindrical basket 251, is placed in space 33 outside the second
dust filter 27b. Cylindrical basket 251 is formed by coupling upper
and lower circular gears 252 together by means of a plurality of
connectors 253, and beater 254 is mounted to connectors 253. Beater
254 is formed by bending metal foil as shown in FIG. 26.
[0221] Circular gears 252 are rotated by driving gear 256 equipped
to motor 255, thereby rotating cylindrical basket 251. Beaters 254
thus vibrate or beat the outer wall of second dust filter 27b.
Rotation of cylindrical basket 251 working as the fourth dust
removing means prompts beaters 254 to vibrate or beat the outer
wall of second dust filter 27b, thereby dropping fine dust 51
attaching to or accumulating on second dust filter 27b at the
pleated section, in particular, at dints 42. Second dust filter 27b
thus can be cleaned. Continuous rotation cleans the entire outer
wall of second dust filter 27b.
[0222] Cylindrical basket 251 is set such that it rotates one turn
in 5 seconds, and motor 255 is powered for 5 seconds by a
controller (not shown) just after electric air blower 21 is stopped
for rotating cylindrical basket 251 one turn, so that the entire
outer wall of second dust filter 27b can be cleaned.
[0223] The same evaluation test as other embodiments is done on the
performance of maintaining the air volume, and the result is shown
in FIG. 27, which tells that the seventh embodiment is more
excellent in this performance than the second embodiment.
[0224] The rotation of cylindrical basket 251 working as the fourth
dust removing means allows removing the dust attaching to second
dust filter 27b, and preventing a decrease in air volume more
positively.
[0225] Beater 254 formed by bending metal foil is used in this
seventh embodiment; however, it can be a plate-like member or an
elastic member such as rubber.
[0226] The fourth dust removing means, i.e. cylindrical basket 254
alone is rotated by a controller (not shown) in this instance;
however, this controller can be used for rotating third dust
removing means 221 demonstrated in embodiment 6, or both of these
dust removing means can be rotated simultaneously or with a time
lag in between.
Embodiment 8
[0227] In this eighth embodiment, differences in structure and
operation from those of embodiments 1-7 are discussed, and elements
similar to those used in the previous embodiments have the same
reference marks and the descriptions thereof are omitted here.
[0228] FIG. 28 shows a perspective view of dust collecting case 5
of the vacuum cleaner in accordance with the eighth embodiment.
FIG. 29A shows a lateral sectional view illustrating the dust
accumulated in dust collecting case 5, and FIG. 29B shows a lateral
sectional view of door 31 left open.
[0229] As shown in FIG. 28, third dust filter 28 shapes like a
truncated cone of which upper and lower ends open, and the upper
end has the same diameter as that of the lower end of first filter
27a, so that the upper end of third dust filter 28 contacts with
the lower end of first filter 27a. The lower end of third dust
filter 28 has a smaller diameter than the inner diameter of the
bottom of dust collector 24, and the lower end solidly contacts
with the bottom of dust collector 24. Other structures remain
unchanged from the first embodiment. Third dust filter 28 is made
of metal mesh of which vent holes are 250 micron across.
[0230] The structure employing the truncated cone shape, of which
both ends are open, maintains the airflow similar to that in the
first embodiment, and fine dust 51 is filtered out by second dust
filter 27b, and rough dust 52 is caught and accumulated in dust
collector 24.
[0231] Fine dust 51 is removed and dropped from second dust filter
27b with the fourth dust removing means demonstrated in embodiment
7, and as shown in FIG. 29A, such fine dust 51 travels along the
slope formed of the bus lines of the truncated cone and positively
arrives at the bottom of dust collector 24. This structure allows
fine dust 51 dropped to the bottom to be distanced from second
filter 27b, so that the suction force less acts on dropped fine
dust 51. This structure thus allows preventing fine dust 51 from
reattaching to filter 27b, and preventing a decrease in air volume
due to clogging in filter 27b.
[0232] The truncated cone shape of third dust filter 28 makes rough
dust 52 resist urging against third dust filter 28 even if the
space within third dust filter 28 is filled up with rough dust 52,
because the lower space is greater than the upper space. As shown
in FIG. 29B, when door 31 opens via hinge 32 mounted on the bottom
of dust collector 24, the dust can be discharged from third dust
filter 28 smoothly and easily by means of gravity. As a result, a
vacuum cleaner excellent in throwing dust away is obtainable.
Embodiment 9
[0233] In this ninth embodiment, differences in structure and
operation from those of embodiments 1-8 are discussed, and elements
similar to those used in the previous embodiments have the same
reference marks and the descriptions thereof are omitted here.
[0234] FIG. 30 shows a perspective view of dust collecting case 5
of the vacuum cleaner in accordance with the ninth embodiment. FIG.
31A shows a lateral sectional view illustrating the dust
accumulated in case 5, and FIG. 31B shows a lateral sectional view
of door 31 left open.
[0235] As shown in FIG. 30, in this ninth embodiment, first dust
filter 27a shapes like a truncated cone of which lower end has a
larger diameter than the upper end. The truncated cone-shaped first
dust filter 27a makes rough dust 52 resist urging against first
dust filter 27a even if greater amount of dust than the capacity of
dust collector 24 is sucked, whereby the space within first dust
filter 27a is filled up with rough dust 52, because the lower space
is greater than the upper space. As shown in FIG. 31B, when door 31
opens via hinge 32 mounted on the bottom of dust collector 24, the
dust can be discharged from first dust filter 27a smoothly and
easily by means of gravity. As a result, a vacuum cleaner excellent
in throwing dust away is obtainable.
Embodiment 10
[0236] In this tenth embodiment, differences in structure and
operation from those of embodiments 1-9 are discussed, and elements
similar to those used in the previous embodiments have the same
reference marks and the descriptions thereof are omitted here.
[0237] FIGS. 32A, 32B and 33 show the structure of dust collecting
case 5 of the vacuum cleaner in accordance with the tenth
embodiment. Third dust filter 28 has opening 321, and dust chamber
322 placed beneath opening 321 and partitioned off in dust
collector 24. The dust removed by second dust removing means 191 is
accommodated in this partitioned chamber 322.
[0238] As shown in FIGS. 32A, 32B, 33, dust chamber 322
communicates with opening 321 prepared just under second dust
removing means 191 for the dust to fall through opening 321 and to
be accommodated positively into dust chamber 322. A shape of the
inlet of chamber 322 agrees with that of opening 321 so that the
dust falling through opening 321 can be accommodated in chamber 322
positively.
[0239] Placement of dust chamber 322 within dust collector 24
allows a user to throw the dust in dust collector 24 away together
with the dust in chamber 322.
[0240] Vent holes 323 are prepared in dust chamber 322, and fourth
dust filter 324 is placed in order to stop up vent holes 323.
Fourth dust filter 324 is made of metal mesh of which air permeable
apertures are 250 micron across, which is the same as that of third
dust filter 28.
[0241] Placement of fourth dust filter 324 in the sucking air duct
is similar to that of third dust filter 28, i.e. fourth dust filter
324 is placed at some point in sub air-duct 29b, i.e. a second
air-duct, running from suction port 6 to the lower end of second
dust filter 27b via the hollow cylinder of first dust filter 27a,
dust collector 24, and vent holes 323 of dust chamber 322.
[0242] Operation of the vacuum cleaner in accordance with the tenth
embodiment is demonstrated hereinafter. Fine dust 51 removed by
second dust removing means 191 falls through opening 321 prepared
in third dust filter 28, so that dust 51 is accommodated into dust
chamber 322, which is placed within dust collector 24. This
structure allows reducing an amount of dust re-raised in cleaning,
and preventing a decrease in the air volume traveling through the
first air-duct, i.e. main air-duct 29a and the second air-duct,
i.e. sub air-duct 29b.
[0243] Vent holes 323 are prepared in dust chamber 322, and vent
holes 323 are stopped up with fourth dust filter 324 made of metal
mesh, thereby securing sub air-duct 29b. In sucking the dust, as
described in embodiment 2, since rough dust 52 is caught in dust
collector 24, the air-duct can be secured along the circumference
of first dust filter 27a and second dust filter 27b, so that the
decrease in air volume can be prevented.
[0244] Fine dust 51 removed is accommodated in dust chamber 322 and
separated from rough dust 52, so that fine dust 51 is prevented
from being re-raised or attaching to second dust filter 27b. As a
result, the decrease in the air volume traveling through main
air-duct 29a and sub air-duct 29b can be prevented more
effectively.
INDUSTRIAL APPLICABILITY
[0245] A vacuum cleaner of the present invention maintains sucking
power at a high level, while its suction force resists lowering
although it sucks dust. This vacuum cleaner thus can substantially
lessen cumbersome take-care jobs such as cleaning of the filters,
throwing the dust away, so that this vacuum cleaner is useful for
various jobs such as a home-use cleaner and a professional-use
cleaner.
* * * * *