U.S. patent application number 12/410702 was filed with the patent office on 2009-10-22 for vacuum cleaner.
This patent application is currently assigned to Black & Decker Inc.. Invention is credited to Andrew Walker.
Application Number | 20090260179 12/410702 |
Document ID | / |
Family ID | 39472340 |
Filed Date | 2009-10-22 |
United States Patent
Application |
20090260179 |
Kind Code |
A1 |
Walker; Andrew |
October 22, 2009 |
Vacuum Cleaner
Abstract
A portable vacuum cleaner having a fan which draws air inwards
through inlet duct and inlet to coarse filter element. Larger dirt
particles are trapped within coarse filter element, and the
filtered air passes through fine filter element and into fan, where
it is expelled through outlet duct and outlet aperture. A cleaning
member mounted on the coarse filter element that engages the fine
filter element so that upon remove of the coarse filter element,
the cleaning member slides along the fine filter element removing
particles thereon.
Inventors: |
Walker; Andrew; (Durham,
GB) |
Correspondence
Address: |
THE BLACK & DECKER CORPORATION
701 EAST JOPPA ROAD, TW199
TOWSON
MD
21286
US
|
Assignee: |
Black & Decker Inc.
Newark
DE
|
Family ID: |
39472340 |
Appl. No.: |
12/410702 |
Filed: |
March 25, 2009 |
Current U.S.
Class: |
15/347 |
Current CPC
Class: |
A47L 5/24 20130101; A47L
9/20 20130101; A47L 9/22 20130101; A47L 9/127 20130101 |
Class at
Publication: |
15/347 |
International
Class: |
A47L 9/10 20060101
A47L009/10 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 18, 2008 |
GB |
0807097.1 |
Claims
1. A vacuum cleaner comprising: an inlet for entry of air; an
outlet for exit of air; suction means for generating a difference
in air pressure between the inlet and the outlet; a first filter
for removing particles larger than a first particle size from air
flowing from said inlet to said outlet; and a second filter for
removing particles larger than a second particle size, smaller than
said first particle size, from air flowing from said first filter
to said outlet; wherein said first filter comprises a cleaning
member mounted thereto and adapted to engage said second filter
such that removal of the first filter causes the cleaning member to
remove particles on said second filter.
2. The vacuum cleaner according to claim 1, wherein said cleaning
member comprises a brush that slides along the surface of the
second filter when said first filter is removed.
3. The vacuum cleaner according to claim 1, wherein the first
filter defines a cavity for collecting particles therein, and said
second filter is arranged outwardly of said first filter.
4. The vacuum cleaner according to claim 1, wherein said first
filter encloses the inlet.
5. The vacuum cleaner according to claim 1, wherein said first
filter is elongate with a longitudinal axis and is adapted to
receive air adjacent a first end thereof, the air entering the
first filter in a direction parallel to the axis.
6. The vacuum cleaner according to claim 1, wherein the second
filter is pleated.
7. The vacuum cleaner according to claim 6, wherein said cleaning
member engages the pleats of said second filter.
8. The vacuum cleaner according to claim 1, wherein the suction
means comprises a fan for displacing air towards said outlet.
9. The vacuum cleaner according to claim 1, wherein said first
filter is elongate, and inlet air is directed in a helical path
over a surface of said elongate first filter.
10. A vacuum cleaner comprising: a housing having an air inlet and
an air outlet; a motor in said housing; a first filter for removing
particles larger than a first particle size; a second filter for
removing particles larger than a second particle size, the second
particle size being smaller than the first particle size; wherein
air passes through the first filter before passing through the
second filter; and a cleaning member mounted to the first filter
and engaging the second filter, so that upon removal of the first
filter from the housing the cleaning member removes particles on
the second filter.
11. The vacuum cleaner of claim 10 wherein the first filter has a
first end and a second end, and the first end of the first filter
encloses the air inlet and the cleaning member is mounted to the
second end of the first filter.
12. The vacuum cleaner of claim 11, wherein the first filter is
located inside the second filter, and the cleaning member engages
the second filter on an end thereof.
13. The vacuum cleaner of claim 12, where the second filter is
pleated, and the cleaning member engages the pleats and upon
removal of the first filter, the cleaning member slides along the
pleats to remove particles thereon.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to Patent Application No.
GB 08 070 97.1 filed Apr. 18, 2008. The entire contents of that
application are expressly incorporated herein by reference
thereto.
FIELD OF THE INVENTION
[0002] The present invention relates to vacuum cleaners, and
particularly, but not exclusively, to portable vacuum cleaners.
BACKGROUND OF THE INVENITON
[0003] Portable vacuum cleaners are known in which a fan mounted in
the housing of the vacuum cleaner causes suction of air into an
intake in the housing and expulsion of air from an exhaust in the
housing. Air drawn through the vacuum cleaner in this way is passed
through a dual filter arrangement consisting of a convex coarse
filter element comprising a screen of durable plastics material
having a large number of small apertures and defining a recess
which contains a fine filter element in the form of a fine filter
medium such as fibrous paper which is crimped or undulated to
maximise its effective surface area in relation to its volume.
Large particles of dirt travelling in the stream of air from the
inlet towards the outlet are trapped on the outer surface of the
coarse filter element, and finer dirt particles which pass through
the coarse filter element are trapped on the fine filter
element.
[0004] Prior art vacuum cleaners of this type suffer from the
drawback that although provision is made for emptying larger dirt
particles from the first, coarse filter element, the fine filter
element must normally operate until it becomes filled with dirt and
dust, and must then be replaced. There is generally no provision
for emptying the fine filter element of dirt and dust until it
becomes necessary to replace that filter element.
BRIEF SUMMARY OF THE INVENTION
[0005] The present disclosure describes a vacuum cleaner comprising
at least one inlet for allowing entry of air, at least one outlet
for allowing exit of air, suction means for generating a difference
in air pressure between the inlet and the outlet, a first filter
means for at least partially removing particles larger than a first
particle size from air flowing from said inlet to said outlet, and
a second filter means for at least partially removing particles
larger than a second particle size, smaller than said first
particle size, from air flowing from said first filter means to
said outlet.
[0006] The first filter means comprises at least one removable
first filter element having at least one cleaning member mounted
thereto and adapted to engage said second filter means, such that
removal of the first filter element, which has a cleaning member
mounted thereto, causes the cleaning member to remove particles
trapped on said second filter means.
[0007] By providing at least one cleaning member mounted to the
first filter element such that the cleaning member engages the
second filter means, this provides the advantage that removal of a
removable first filter element having (e.g. for emptying of dirt
therefrom) automatically removes some of the dirt from the second
filter means at the same time. This in turn provides the advantage
of prolonging the useful lifetime of the second filter means.
[0008] In one embodiment, the cleaning member comprises a brush.
Additionally, the first filter element defines a respective recess
therein for collecting particles, and said second filter means is
arranged outwardly of the first filter element.
[0009] By providing a first filter element defining a respective
recess therein for collecting particles, this provides the
advantage that by collecting particles on the inside of said first
filter element, the surface area of the first filter element can be
increased, together with the volume of the corresponding particle
collection recess, and no reduction of the particle storage space
available within the vacuum cleaner results, which would be the
case with prior art arrangements in which dirt is collected on the
outside of a convex filter element. Also, by collecting particles
in the interior of a recess defined by the first filter element,
this provides the advantage of enabling dirt collected in the
recess to be more effectively confined and therefore more tidily
removed from the vacuum cleaner.
[0010] The first filter element may have a concave inner surface.
This provides the advantage of reducing the instances of incoming
particles becoming stuck to the first filter element.
[0011] The first filter element may comprise a screen having
apertures therein. The filter element may comprise a mesh.
[0012] The vacuum cleaner is adapted to be opened to allow emptying
of particles from said first filter means.
[0013] In another embodiment, the first filter element is elongate
and adapted to receive air adjacent a first end thereof and having
a component of motion from said first end towards a second end
thereof.
[0014] This provides the advantage of causing air to have a
component of motion axially along the first filter element, as a
result of which that filter element tends to fill up with dirt from
one end. Since the filter element may become blocked in those
regions where it fills with particles, the tendency of an incoming
air stream to disturb particles already collected in the interior
of a said first filter element is thereby reduced. In addition,
this at the same time provides the advantage giving an indication
when a said first filter element needs to be emptied, since the
first filter element will no longer be effective.
[0015] The second filter means may comprise a second filter
element, wherein the second filter element is undulated. This
provides the advantage of increasing the effective surface area of
the second filter means for a given volume of filter element. The
cleaning member may engage the undulations in said second filter
member.
[0016] In another embodiment, the first filter element is elongate,
and the vacuum cleaner in use directs air in a helical path over a
surface of said elongate first filter element.
[0017] This provides the advantage of directing incoming air onto
as large a proportion of the surface area of the filter element as
possible, and not just over that part of the surface area facing
towards the direction of the incoming air. This in turn provides
the advantage of maximising the efficiency of the first filter
means.
[0018] The vacuum cleaner may further comprise an inlet duct for
introducing air to the first filter element having a component of
movement transverse to the longitudinal axis of said first filter
element.
[0019] The vacuum cleaner may further comprise outlet duct means at
least partially surrounding said first and second filter means, for
directing air from said second filter means to said outlet.
[0020] This provides the advantage of enabling the cross-sectional
area of the airstream passing out of the outlet or outlets to be
made larger than that of the airstream received from the inlet or
inlets, as a result of which the velocity of air passing out of the
outlets can be minimised. This is particularly advantageous in the
case of suffers from asthma or other allergies, since the amount of
dust blown towards a user of the vacuum cleaner by exhausted air is
minimised. Furthermore, by providing outlet duct means which at
least partially surrounds said first and second filter means, this
provides the advantage of enabling the vacuum cleaner to still be
made of compact construction.
BRIEF DESCRIPTION OF THE INVENTION
[0021] Preferred embodiments of the invention will now be
described, by way of example only and not in any limitative sense,
with reference to the accompanying drawings, in which:
[0022] FIG. 1 is a schematic perspective view of a portable vacuum
cleaner of a first embodiment of the present invention in a closed
condition thereof;
[0023] FIG. 2 is a view along the line B-B of the portable vacuum
cleaner of FIG. 1 in an open condition thereof;
[0024] FIG. 3 is a cross-sectional end view of portable vacuum
cleaner of a second embodiment of the present invention; and
[0025] FIG. 4 is a view along the line A-A in FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Referring to FIG. 1, a portable vacuum cleaner 1 comprises a
housing 2 of durable plastics material and consisting of a main
part 3 to which a rear part 4 is pivotally attached by means of a
hinge 5.
[0027] A diffuser 6 is mounted within the main part 3 of housing 2
and has a fan 7 mounted at the end thereof remote from the rear
part 4 of housing 2. The fan 7 is powered by an electric motor 8 to
displace air radially outwards through apertures 9.
[0028] The main part 3 of housing 2 has an intake 10 at a front end
thereof for receiving air into an inlet duct 11 which directs air
through 180.degree. into inlet 12 of a removable first, coarse
filter element 13 in the form of a generally cylindrical cup,
closed at one end thereof, and provided with suitably sized holes
14. The cup is made of any suitable material which will be well
known to persons skilled in the art, such as durable plastics or
metal, and is designed to trap larger particles of dirt in its
interior.
[0029] A brush 20 is mounted to the closed end of coarse filter
element 13. The brush 20 has bristles extending outwardly of the
longitudinal axis of the coarse filter element 13.
[0030] The coarse filter element 13 is surrounded by a generally
cylindrical second, fine filter element 15 of fibrous paper or
textile material, which is pleated to maximise the effective
surface area of the filter element 15 in relation to its volume.
The bristles of brush 20 fit within the pleats of fine filter
element 15. The fine filter element 15 is sealed at the end thereof
remote from fan 7 to the coarse filter element 13, and is
surrounded by a chamber 16 which is sealed to an input of the fan
7. This ensures that air passing through the fine filter element 15
enters the fan 7.
[0031] The apertures 9 of fan 7 direct air radially outwards and
then along an annular outlet duct 17, formed by the space between
the inner wall of diffuser 6 and outer wall of chamber 16, to a
series of exhaust outlets 18 in the rear part 4 of housing 2.
[0032] The operation of the vacuum cleaner 1 shown in FIG. 1 will
now be described.
[0033] When the fan 7 is actuated by means of motor 8, air is
displaced outwards through apertures 9 along outlet duct 17 and
exhausted through outlet apertures 18. As a result, air is drawn
into the fan 7 through intake 10, along inlet duct 11, and into
inlet 12 of coarse filter element 13, where large particles
contained in the air are trapped by holes 14.
[0034] Air passing out of coarse filter element 13 is then drawn
through fine filter element 15, where smaller particles are
removed, and is then drawn into fan 7 and expelled from apertures 9
and along outlet duct 17. As can be seen from FIG. 1, because the
air stream through coarse filter element 13 has a significant axial
component, the coarse filter element 13 fills up from its end
remote from the rear part 4 of housing 2, i.e. it fills up from its
downstream end. This means that dirt collected in the interior of
coarse filter element 13 is not disturbed of otherwise displaced by
incoming air.
[0035] By constructing an annular exhaust aperture 18 that
surrounds the chamber 16, the outlet duct 17 can be made to have
relatively large surface area, as a result of which the velocity of
air discharged though outlet 18 is minimised. This minimises the
disturbance of dirt and dust in the vicinity of the outlet 18,
which is of particular advantage in the case of users of the vacuum
cleaner suffering from an allergy to dust.
[0036] Referring now to FIG. 2, which shows a view along the line
B-B in FIG. 1, when the rear part 4 of housing 2 is pivoted
relative to the main part 3 about hinge 5, the coarse filter
element 13 containing larger dirt particles can be removed from the
housing 2 to enable the filter element 13 to be emptied. At the
same time, as the coarse filter element 13 is withdrawn from the
main part 3 of housing 2, the bristles of the brush 20 are moved
axially along the pleats of fine filter element 15. This causes
dust and/or dirt to be displaced from the fine filter element.
[0037] Referring to FIGS. 3 and 4, which shows a second embodiment
of the invention and in which parts common to the embodiment of
FIGS. 1 and 2 are denoted by like reference numerals but increased
by 100, an inlet duct 111 is connected to an intake (not shown)
provided at a distal end thereof with a suitable cleaning accessory
such as a brush. The inlet duct 111 is removably mounted to inlet
112 of coarse filter element 113 by means of a bayonet-type fitting
130.
[0038] As can be seen from FIG. 3, inlet 112 is of generally
cylindrical internal profile and longitudinal axis 131 of the inlet
duct 111 is slightly displaced from the axial plane 132 of inlet
112, as a result of which circular motion in the direction of arrow
C is imparted to air entering inlet 112 from inlet duct 111.
[0039] The coarse filter element 113 is blocked by an un-perforated
end cap 133 at the end thereof remote from inlet 112, and a brush
120 is mounted to the end cap 133. The coarse filter element 113 is
surrounded by a cylindrical fine filter element 115 of pleated
fibrous paper such that the bristles of brush 120 fit within the
pleats of fine filter element 115. The fine filter element 115 is
also sealed by means of an un-perforated end cap 134 adjacent end
cap 133, and is sealed at fitting 135 within chamber 116. As a
result, any air passing through coarse filter element 113 is
directed through the sides thereof into fine filter element
115.
[0040] A fan 107 having blades 136 is arranged at the end of
chamber 116 remote from fitting 135 and expels air radially
outwards into annular outlet duct 117 which surrounds chamber 116.
The air is then exhausted from annular exhaust aperture 118.
[0041] In operation, actuation of fan 107 causes expulsion of air
along annular outlet duct 117, as a result of which air is drawn
axially inwards through inlet duct 111, inlet 112 and into the
interior of coarse filter element 113 in the direction of arrow D
shown in FIG. 4. As a result of the combination of axial motion
(arrow D in FIG. 4) and circular motion (arrow C in FIG. 3), air
undergoes a spiral motion along filter element 113, as a result of
which incoming air travels over the entire side internal surface of
coarse filter element 113. This maximises the effective use of
filter element 113. Also, because the internal surface of filter
element 113 is concave, dirt particles are less likely to become
trapped in the holes of filter element 113. As was the case with
the embodiment of FIGS. 1 and 2, dirt particles trapped by coarse
filter element 113 tend to congregate at the closed distal end of
filter element 113, as a result of which dirt is not disturbed by
incoming air.
[0042] After passing through filter element 113, the filtered air
passes through fine filter element 115 and through chamber 116 to
fan 107. Where it is expelled into outlet duct 117 and then
discharged through exhaust aperture 118.
[0043] In order to empty dirt from the coarse filter element 113,
the inlet 112 is removed from the housing of the vacuum cleaner,
and the coarse filter element 113 is removed from the housing. As
the coarse filter element 113 is withdrawn from the housing, the
bristles of brush 120 move axially along the individual pleats of
fine filter element 115 and thereby displace dust and/or dirt
trapped on the fine filter element 115.
[0044] It will be appreciated by persons skilled in the art that
the above embodiments have been described by way of example only
and not in any limitative sense, and that various alterations and
modifications are possible without departure from the scope of the
invention as defined by the appended claims.
* * * * *