Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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SURFACE CLEANING APPARATUS
This invention relates to a surface cleaning apparatus
utilising both a rotatable brush assembly and a plurality
of separate means for creating suction to retrieve debris
from a surface.
In conventional vacuum cleaners, debris, for example dirt
and dust, is retrieved from a surface by means of motor
generated suction and the debris is collected in a suitable
collection means, for example a filter bag or receptacle.
The quantity of debris that can be picked up from the
surface being cleaned depends on the efficiency of the
motor generating the suction. Further, it is impractical
simply to replace a mains-powered motor with a battery-
powered motor due to the lower suction power that can be
generated.
Vacuum cleaners are not suitable for the collection of
large debris. The generated suction can cause the debris
collecting aperture of the vacuum cleaner to become
substantially sealed to a surface to be cleaned, preventing
large debris from entering the aperture and being removed
from the surface. Also, if large pieces of debris are
sucked up it is known for them to cause a blockage of the
pathways through which suction draws the debris.
Vacuum cleaners with a hose and a battery powered head are
known, including cleaners in which the cleaning head can be
detached and used independently of the vacuum cleaner in
what is known as a sweeper mode. The independent battery
powered head has a rotating brush and a debris collection
means independent of the collection means of the vacuum
cleaner. The debris collection means has a port to which a
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suction creating means of the vacuum cleaner can be
connected when used in a vacuum cleaning mode.
The problem with the known vacuum cleaners with an
independent cleaning head is that blocking of the pathway
from the independent collection means and the suction means
can occur. A relatively large amount of debris can be
collected in the collection means of the independent head
during use in the sweeper mode. On reconnecting the head to
the suction means, the relatively large amount of debris is
drawn substantially as one single mass towards the suction
means and can lead to blockages.
A known solution to the problem of blockages is the
provision of a filter means which only allows particles
below a certain size to enter a connection between the
independent head and the suction means. However, the filter
relatively quickly becomes blocked due to the relatively
small surface area of the filter and the potentially large
amount of debris that can be present in the collection
means of the independent head. Therefore, the performance
of such vacuum cleaners can be impaired and such vacuum
cleaners have reduced suction power.
Conventional sweepers use a brush arrangement to retrieve
debris from a surface. The brush arrangement is adapted to
gather up and remove relatively large pieces of debris from
a surface, but fine particles of dust, for example, are not
efficiently removed from the surface being cleaned,
especially from crevices and deep inside soft furnishings.
Further, conventional sweepers do not efficiently remove
light debris, for example fine-particles of dust, from hard
floors
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It is therefore an object of the present invention to
provide a surface cleaning apparatus utilising both a
rotatable brush assembly and a plurality of separate means
for creating suction to retrieve debris from a surface and
to overcome, or at least ameliorate, the problems of known
apparatus.
According to the present invention there is provided a
surface cleaning apparatus comprising:
a debris retrieval body;
a first collection means and a second collection means
provided within the debris retrieval body for accumulating
debris from a surface to be cleaned;
a rotatable elongate brush arrangement provided within the
debris retrieval body and adapted to retrieve a first
portion of debris from the surface to be cleaned and to
direct the first portion of the debris along a first
pathway into the first collection means;
a first inlet aperture provided in the debris retrieval
body for the passage along a second pathway, independent of
the first pathway, of a second portion of debris from the
surface to be cleaned to the second collection means, the
first inlet aperture communicating with a first means for
creating suction; and
a second inlet aperture provided in the debris retrieval
body for the passage along a third pathway, independent of
the first and second pathways, of a third portion of debris
from the surface to be cleaned to means for connection to
a second means for creating suction.
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The first means for creating suction may be provided within
the debris retrieval body.
The second means for creating suction may be provided
remotely from the debris retrieval body.
The remotely provided means for creating suction may be
incorporated into a cleaner body adapted for attachment to
the debris retrieval body.
The first means for creating suction and/or the second
means for creating suction may be a cyclonic suction
generating system.
The first inlet aperture and/or the second inlet aperture
may be elongate.
The first inlet aperture and/or the second inlet aperture
may be spaced from the elongate brush arrangement.
A plurality of perforations may be provided in a removable
plate covering the first inlet aperture and/or the second
inlet aperture.
The debris retrieval body may be provided with an opening
through which bristles of the elongate brush arrangement
extend for retrieving the first portion of debris.
The opening for the bristles may be separate from the first
and/or the second inlet aperture.
The first inlet aperture and/or the second inlet aperture
may extend substantially parallel and adjacent to the
opening for the bristles of the elongate brush arrangement.
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The second inlet aperture may have a greater area than the
first inlet aperture.
The apparatus may be adapted to convey the first portion of
debris directly to the first collection means.
The first collection means and/or the second collection
means may be in the form of a removable tray.
A lower edge of a front wall of the debris retrieval body
may be maintained at a distance from the surface to be
cleaned. The lower edge of the front wall of the debris
retrieval body may be provided with a recess.
A battery may be provided to provide power to rotate the
elongate brush arrangement and to power the first means for
creating suction.
A mains power supply may be provided to power the second
means for creating suction.
For a better understanding of the present invention and to
show more clearly how it may be carried into effect
reference will now be made, by way of example, to the
accompanying drawings in which:
Figure 1 is a cross-sectional view of an embodiment of a
surface cleaning apparatus according to the present
invention;
Figure 2 is a perspective cut-away view, from above, of the
surface cleaning apparatus shown in Figure 1;
Figure 3 is a perspective view, from below, of the surface
cleaning apparatus shown in Figure 1; and
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Figure 4 is the perspective view of the surface cleaning
apparatus shown in Figure 3 with a portion of the lower
surface removed.
Referring to Figures 1 and 2, a surface cleaning apparatus
1 has a debris retrieval body 3 comprising five
compartments 5, 7, 9, 11 and 13 and a handle 15 which acts
as a means for connection to a first suction creating means
(not shown), for example a mains powered vacuum cleaner,
preferably a cyclonic suction generating vacuum cleaner,
provided external to the debris retrieval body.
As will be described hereinafter, the cleaning apparatus 1
can be used in an external vacuum mode to remove debris
from a surface to be cleaned by means of the first suction
creating means. The cleaning apparatus 1 can also be used
in an internal vacuum mode to remove debris from a surface
to be cleaned by means of a second suction creating means
17 provided within a first rear compartment 11 of the
debris retrieval body suction. Consequently, the apparatus
can be used independently of any external suction creating
means.
The handle 15 is in the form of an elongate tubular member
provided at the rear 19 of the debris retrieval body 3.
The handle 15 is pivotably attached to the rear 19 of the
debris retrieval body 3 by means of a pivot member 21.
Swivel means 23 is provided between the pivot member 21 and
the handle 15, as shown in Figures 1 and 2. The swivel
means 23 allows the handle 15 to rotate about the axis
thereof relative to the debris retrieval body 3 and the
pivot member 21 allows the handle 15 to pivot about an axis
transverse to the axial direction of the handle 15.
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The pivot member 21 and the swivel means 23 enable the
sweeping apparatus 1 to be steered by the user.
The tube of the handle 15 forms the means for connection to
the first suction creating means by providing a portion of
a channel 25 (see Figure 1) which passes down the length of
the elongate handle, through the swivel means 23 and the
pivot member 21, and through which suction created by the
external suction means, for example a vacuum cleaner
apparatus, can be transmitted to within the debris
retrieval body 3.
An upper end 26 of the connection means 15, furthest from
the debris retrieval body 3, is shaped to be complementary
with connecting portions of, for example, a hose member of
the suction creating means, such that the connecting
portions of the suction creating means can be, for example,
push fitted onto the upper end 26 when the apparatus is
used in external vacuum mode.
The shape of the upper end 26 also enables extension
members to be added to the handle when the apparatus is
used in the internal vacuum mode.
A front compartment 5 houses an elongate rotatable brush
arrangement 27 comprising rows of tufts of bristles
attached to a cylindrical member 29. For convenience, a
front wall 31 of the front compartment 5 (see Figure 1) is
arcuate and extends around the periphery of the brush
arrangement 27. The front wall 31 may be removable. The
bottom of the front compartment 5 is provided with an
opening 32 to allow the bristles of the brush arrangement
27 to contact a floor, carpet or like surface over which
the surface cleaning apparatus 1 is to be moved.
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The front wall 31 of the front compartment 5 forms the
front wall of the surface cleaning apparatus 1. In use, a
lower edge 33 of the front wall is maintained a distance
from the surface to be cleaned. The distance between the
lowest portion of the lower edge 33 of the front wall 31
and the surface to be cleaned is in a range from 5mm to
8mm. The lower edge 33 of the front wall 31 is non-planar
(see Figures 3 and 4) . The lower edge 33 incorporates a
recess 35, as shown in Figures 3 and 4, with a width, for
example, in a range from about 20mm to about 150mm,
preferably about 60mm. The depth of the recess 35, that is
the distance between the top of the recess 35 and the
lowest portion of the lower edge 33, is nominally about
10mm but may, for example, be in the range from about 4mm
to about 20mm. The recess 35 allows debris, such as dust,
dirt and the like, too large to pass under the lowest
portion of the lower edge 33 to pass into the front
compartment 5 and be picked up by means of the brush
arrangement 27.
As shown in Figure 1, a narrow elongate flange 37,
substantially parallel to the surface to be cleaned, is
provided along the lower edge 33 of the front wall 31
extending both outward and inward of the front compartment.
The flange is adapted to substantially prevent air
turbulence, generated by the rotation of the brush
arrangement 27, forcing debris away from the front of the
apparatus 1. The inward extending edge of the flange
extends from the front wall 31 towards the elongate brush
arrangement 27. The end of the flange 37 nearest to the
brush arrangement 27 is positioned such that there is no
contact between the flange and the bristles of the elongate
brush arrangement.
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At the rear of the front compartment 5 is a rearwardly
inclined wall 39 which allows debris, such as dust, dirt
and the like, to be propelled up the wall 39 due to
rotation of the brush arrangement 27 (shown by arrow 311 in
Figure 1) and to pass over the wall 39 into a first
intermediate compartment 7 which will be described in more
detail hereinafter. The wall 39 extends upwardly to about
the same height as the top of the brush arrangement 27 and
is angled rearwardly (i.e. away from the front compartment
5) at an angle of about 18 degrees. The precise angle is
not important, but the inclination facilitates the passage
of the debris up and over the wall 39 and at the same time
facilitates retention of the debris within the rear
compartment.
The brush arrangement 27 in the front compartment 5 extends
substantially the entire width of the front compartment 5
and is provided with two helically arranged rows of
bristles. The length of the bristles, for example, is in a
range from 8mm to 25mm, preferably a range from 14mm to
17mm. The thickness of individual bristles is in a range
from 0.04mm to 0.3mm, preferably in a range from 0.06mm to
0.25mm. The bristles are arranged in tufts and the tufts
have a diameter in a range from 1.5mm to 5mm, preferably a
range from 2mm to 3mm.
The elongate brush arrangement 27 is arranged such that it
can be detached from retaining portions (not shown) of the
debris retrieval body 3, for example for cleaning or for
replacement.
An auxiliary rotary brush 41 (shown in Figures 3 and 4) is
provided at one side of the brush arrangement 27. Such an
auxiliary brush 41 is described, for example, in GB-A-1 547
286 or GB-A-2 393 900. Such an auxiliary brush 41 is able
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to sweep debris into the path of the brush arrangement 27.
The auxiliary brush 41 is driven by gearing from the brush
arrangement 27. Alternative means of driving the auxiliary
brush 41, for example by friction with the surface to be
swept, may also be used. The auxiliary brush 41 is provided
in a support member 43 and extends outwardly beyond the
debris retrieval body 3. The auxiliary brush 41 comprises
a cylindrical body rotatable about an axis which is
inclined to the vertical by about 10 degrees so as to
extend outwardly beyond the debris retrieval body 3.
Bristles protrude radially outwardly from the periphery of
the cylindrical body, preferably at an angle of about 80
degrees to the axis of rotation, so as to form a cone which
increases in cross-section with increasing distance from
the debris retrieval body 3.
The support member 43 of the auxiliary brush 41 is
detachable from the debris retrieval body 3, for example
for the cleaning or replacement of the auxiliary brush 41.
The support member 43 is held in position, for example, by
two protruding members which fit within complementary
apertures in the debris retrieval body 3. The support
member 43 is secured to the debris retrieval body 3, for
example, by means of a releasable catch on the side of the
support member 43 furthest from the front wall 31 of the
debris retrieval body 3.
The first intermediate compartment 7, shown in Figures 1 to
4, is provided in the form of a removable tray 47
positioned in a recess provided in the debris retrieval
body 3 between the rear wall 39 of the front compartment 5,
front walls of the first rear compartment 11 and a second
rear compartment 13, and an upper wall of the debris
retrieval body. The first intermediate compartment 7 is
open on an upper face and on its front side in a position
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corresponding to the region between the top of the
rearwardly inclined wall 39 of the front compartment and
the upper side of the debris retrieval body 3. Debris
propelled over the rear wall 39 of the front compartment
can enter the tray 47 through the opening in the front
side.
The first intermediate compartment 7 in the form of the
tray 47 is removable from the debris retrieval body 3, for
example for emptying, by sliding the tray 47 in a lateral
direction out of the recess in the debris retrieval body.
A transparent window may be provided in the first
intermediate compartment to enable a user to determine if
the first intermediate compartment requires emptying.
The second intermediate compartment 9 (shown in Figure 2)
is provided to one side of the recess 49 of the debris
retrieval body. The second intermediate compartment 9
houses a rechargeable battery pack 51. The battery pack 51
may be connected to a mains power supply (not shown) for
recharging the battery pack 51. The battery pack 51 may be
connected either to the mains supply whenever the apparatus
1 is not in use or at suitable times when the battery pack
51 has become depleted. As an alternative to a rechargeable
battery pack 51, the apparatus 1 could employ disposable
batteries or be mains powered.
The rear 19 of the debris retrieval body comprises a first
rear compartment 11 and a second rear compartment 13
arranged side by side behind the rear walls of the first
and second intermediate compartments 7, 9 as shown in
Figure 2. The first rear compartment 11 and the second rear
compartment 13 are separated from each other by an internal
wall 63.
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The first rear compartment 11 houses an electric motor (not
shown). The motor is used to rotate the brush arrangement
27 by way of toothed rollers attached to each of the motor
and the brush arrangement 27 and a toothed belt 55, for
example of elastomeric material, extending around the
rollers (see Figure 2 where the upper wall of the debris
retrieval body and the brush arrangement have been omitted
to show a portion of the belt arrangement) . The motor is
powered by the rechargeable battery pack in the second
intermediate compartment 9.
Electrical connections including a printed circuit board 52
are provided between the rechargeable battery pack 51 and
the motor. Switch means 53 (shown in Figure 2) is provided
on an upper region of the first rear compartment 11 to
permit a user to energise and de-energise the motor as
desired.
The first rear compartment 11 also houses the second
suction creating means 17 which is in the form of a
cyclonic suction creating assembly as known to a person
skilled in the art. As shown in Figure 3, the second
suction creating means 17 includes a cyclone body, a
cyclonic separator 57 and an impeller 59 to create suction
in the debris retrieval body 3. A truncated conical-shaped
end 61 of the cyclone body, furthest from the impeller 59,
protrudes into the second rear compartment 13 through an
aperture in the internal wall 63 between the first rear
compartment 11 and the second rear compartment 13.
The second suction creating means 17 may be powered by the
same motor as that used to rotate the elongate brush
arrangement or may be powered by a separated motor (not
shown), for example energised/de-energised by an additional
switch means (not shown).
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The exhaust from the cyclonic separator 57 exits the
apparatus 1 through an apertured region in the f orm of a
removable section (not shown) of an upper surface of the
first rear compartment 11. The apertured region is provided
with a replaceable filter member to minimise the
possibility of any debris particles exiting the body.
The second rear compartment 13, in the form of a removable
compartment, is provided in a recess provided in the debris
retrieval body 3 between a rear wall 39 of the debris
retrieval body and a rear wall of the first intermediate
compartment 7. The second rear compartment 13 is only open
in a central region of a face nearest to the internal wall
63. The open central region corresponds to the position of
the aperture in the internal wall 63 through which the
truncated conical end 61 of the cyclone body protrudes.
Debris propelled out of the truncated conical end 61 of the
cyclone body is deposited in the second rear compartment
13.
The second rear compartment 13 is removable from the debris
retrieval body 3, for example for emptying, by sliding the
second rear compartment 13 in a horizontal direction away
from the first rear compartment 11 of the debris retrieval
body. A transparent window may be provided in the second
rear compartment 13 to enable a user to determine if the
second rear compartment requires emptying.
Ground-engaging wheels 67 to assist mobility of the surface
cleaning apparatus 1 are provided on the rear of the debris
retrieval body.
As shown in Figures 1 and 4, a first elongate chamber 69,
enclosed at its upper surface, is provided rearward of the
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inclined wall 39 of the front compartment 5. The first
elongate chamber 69 is provided with an outlet 71 from the
chamber 69 which is positioned in the region of one end of
the chamber 69.
A duct 73 (shown in Figure 4) connects the outlet 71
provided in the rear wall of the first elongate chamber 69
with the second suction creating means 17 in the first rear
compartment 11. The duct 73 is substantially the width of
the outlet 71 and is positioned beneath the first
intermediate compartment 7. An upper wall of the duct 73 is
positioned adjacent to a portion of the lower wall of the
first intermediate compartment 7. The lower wall of the
duct 73 is formed by a section 74 of the lower wall of the
surface cleaning apparatus 1 (see Figure 3). The section 74
of the lower wall is removable to enable the duct to be
cleaned.
Figures 1 and 3 show a nozzle in the form of an elongate
inlet aperture 75 in a lower face of the first chamber 69.
The inlet aperture 75 is separate from the opening 32 for
the brush bristles of the front compartment 5. During the
use of the apparatus 1, the inlet aperture 75 enables
suction created by the internal second suction means within
the first chamber 69 to be applied in close proximity to a
surface to be cleaned. The application of suction via the
inlet aperture 75 in close proximity to the surface to be
cleaned enables debris to be removed from the surface as
will be described hereinafter.
The area of the inlet aperture 75 is less than the cross-
sectional area of the first chamber 69.
For a given power usage of a motor associated with suction
creating means of a vacuum cleaner, a relatively constant
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volume of air will be drawn through the suction creating
means. To enable debris to be retrieved from a surface, the
debris must be entrained in the air that enters the
apparatus through an aperture forming a nozzle. To achieve
this, a relatively high air speed must be generated through
the nozzle. In conventional vacuum cleaners the width of
the aperture is relatively large to enable relatively large
amounts of debris on a surface to be removed by a single
pass of the aperture over the surface. Therefore, a
relatively large volume of air must be drawn though the
nozzle of a conventional vacuum cleaner in order to achieve
sufficient air speed to entrain debris. As such, a motor
using relatively high amounts of power is required in order
to draw such relatively large volumes of air through the
wide apertured nozzle.
For a given volume of air drawn into an apparatus in
accordance with the present invention for a given power
usage of a motor, the presence of the narrow inlet aperture
75 and the associated lower area compared to the cross-
sectional area of the first chamber 69 and/or the cross-
sectional area of a passage through which the air is drawn
causes the speed of the air on passing through the inlet
aperture 75 and/or the passage to be increased compared to
the speed of the air which passes through the first chamber
69 to the second suction creating means 17. As the use of
the suction means is directed to retrieving fine dust,
which has not been removed along with larger pieces of
debris by the rotating brush arrangement, there is no need
for a wide aperture for retrieving larger pieces of debris.
Therefore, it is possible to generate sufficiently high air
speed through the inlet aperture forming the nozzle, to
entrain fine dust, by means of the narrow width of the
inlet aperture 75 constricting the volume of air as it
passes through the inlet aperture. As such, the flow of air
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through the inlet aperture can have a high air speed
generated in this way for a relatively low power usage by
the motor of the second suction means. The narrow, elongate
inlet aperture enables effective cleaning of the surface
over which the inlet aperture is positioned in use.
The increased cross-sectional area of the chamber 69
compared to the area of the inlet aperture 75 and the
resultant lower speed of air flow in the chamber 69 is also
beneficial in that losses resulting from friction between
the air flow and walls of the chamber are reduced by the
slowing of the air flow on entering the chamber. The power
usage by the motor of the second suction means can be
minimised by the reduction of the frictional losses in the
chamber by means of the difference between the area of the
inlet aperture and the cross-sectional area of the chamber.
The provision of a chamber with a relatively large cross-
sectional area also helps to minimise the potential of a
blockage being formed in the chamber by the dust entrained
in the air flow entering the chamber from the inlet
aperture.
As shown in Figure 3, the inlet aperture 75 of the first
chamber 69 extends along substantially the entire length of
the longitudinal extent of the opening 32 in the front
compartment 5.
A cover 77 (see Figure 3) is provided over the entire
length of the inlet aperture 75 of the first chamber 69,
releasably secured to the debris retrieval body 3 by
fastening means, for example screw fasteners. The cover 77
has a series of elongate apertures to further reduce the
width of the inlet aperture 75 between the surface to be
cleaned and the first chamber 69.
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Provided rearward of the first chamber 69 is a second
elongate chamber 79 enclosed at its upper surface, as shown
in Figure 1. The second chamber 79 is provided with an
outlet 81 from the chamber 79 which is positioned
substantially equidistant from the side walls of the debris
retrieval body (as shown in Figure 4).
A duct 83 (shown in Figure 4) connects the outlet 81
provided in the rear wall of the second elongate chamber 79
with the first suction creating means. The duct 83 has a
fluted shape such that in a region of the duct adjacent to
the outlet 81, the duct 83 widens to extend substantially
across the entire width of the outlet 81. The duct 83
between the outlet 81 of the second chamber 79 and the
first suction creating means is separate from the duct 73
between the outlet 71 of the first chamber 69 and the
second suction creating means 17.
An upper wall of the duct 83 is positioned adjacent to a
portion of the lower wall of the first intermediate
compartment 7. The lower wall of the duct 83 is formed by
the section 74 of the lower wall of the surface cleaning
apparatus 1. The section 74 of the lower wall, as described
hereinbefore, is removable to enable the duct 83 to be
cleaned.
Figure 3 shows a nozzle in the form of an elongate inlet
aperture 85 in a lower face of the second chamber 79. The
inlet aperture 85 of the second chamber 69 is separate from
the opening 32 for the brush bristles of the front
compartment 5 and from the inlet 75 of the first chamber
69. During the use of the apparatus 1, the inlet aperture
85 enables suction created by the external first suction
means within the second chamber 79 to be applied in close
proximity to a surface to be cleaned. The application of
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suction via the inlet aperture 85 in close proximity to the
surface to be cleaned enables debris to be removed from the
surface as will be described hereinafter.
As with the inlet aperture 75 of the first chamber 69, the
area of the inlet aperture 85 of the second chamber 79 is
less than the cross-sectional area of the chamber 79. The
difference in area results in an increase in the speed of
air flow through the inlet aperture 75, as described
hereinbefore. Therefore, it is possible to generate
sufficiently high air speed through the inlet aperture
forming the nozzle, to entrain dust and small debris, by
means of the width of the inlet aperture constricting the
volume of air as it passes through the inlet aperture. As
such, the flow of air through the inlet aperture can have
a high air speed generated in this way for a relatively low
power usage by the motor of the first suction means. The
narrow, elongate inlet aperture enables effective cleaning
of the surface over which the aperture is positioned in
use.
As discussed hereinbefore, the increased cross-sectional
area of the chamber 79 compared to the area of the inlet
aperture 85 and the resultant lower speed of air flow in
the chamber 79 is also beneficial in that losses resulting
from friction between the air flow and walls of the chamber
are reduced by the slowing of the air flow on entering the
chamber. The power usage by the motor of the first suction
means can be minimised by the reduction of the frictional
losses in the chamber by means of the difference between
the area of the inlet aperture and the cross-sectional area
of the chamber.
The provision of a chamber with a relatively large cross-
sectional area also helps to minimise the potential of a
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blockage being formed in the chamber by the dust entrained
in the air flow entering the chamber from the inlet
aperture.
As shown in Figure 3, the inlet aperture 85 of the second
chamber 79 extends along substantially the entire length of
the longitudinal extent of the opening 32 in the front
compartment 5.
The width of the inlet apertures 75, 85 are relatively
narrow, for example in a range from 1 to 20 mm, or in a
range from 1 to 10 mm. If desired, the width of the inlet
aperture may be in a range from 2 to 4 mm.
The width, and thus the area, of the inlet aperture 85 of
the second chamber 79 is greater than the width, and thus
the area, of the inlet aperture 75 of the first chamber 69.
The inlet aperture 85 of the second chamber 79 can, and
generally does, have a greater area than the inlet aperture
75 of the first chamber 69 as there can be more power
available to the external first means to create suction
compared to the power available from the battery pack 51
for the internal second means to create suction 17.
The cover 77, described hereinbefore, is provided over the
entire length of the inlet aperture 85. The cover 77 has a
series of elongate apertures to further reduce the width of
the inlet aperture 85 between the surface to be cleaned and
the chamber 79.
As shown in Figures 1 and 3, provided between the inlet
aperture 75 of the first chamber 69 and the inlet aperture
85 of the second chamber 79 is a cleaning strip assembly
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87, for example for cleaning hard floor surfaces, as known
to a person skilled in the art.
Ground-engaging wheels 89 to assist mobility of the surface
cleaning apparatus 1 are provided in a region adjacent to
the inlets 75, 85 of the debris retrieval body 3 (see
Figures 1 and 3).
In use in the external vacuum mode, a surface cleaning
apparatus 1 in accordance with the present invention is
placed upon a surface to be cleaned, such as a carpet, and
the switch 53 is operated to energise the brush assembly
motor. The brush arrangement 27 is rotated to sweep debris
from the surface to be cleaned and then propel the debris
up and over the inclined wall 39 and into the removable
tray 47 where it is temporarily stored. That is, the debris
passes along path 311 as shown in Figure 1.
As the surface cleaning apparatus 1 is moved over the
surface to be cleaned, with the brush arrangement 27
rotating, further debris is similarly swept from the
surface and propelled up and over the wall 39 into the
first intermediate compartment 7.
As shown in Figure 4, due to the external first suction
creating means creating a vacuum in the debris retrieval
body of the apparatus 1, debris passes through the inlet
aperture 85 of the second elongate chamber 79 into the duct
83 via the outlet 81 provided in the rear wall of the
elongate chamber 79. The duct 83 transfers the debris, in
the direction of arrow 313, from the inlet aperture 85
beneath the first intermediate compartment 7 and on to a
collection means provided in the first suction creating
means via the handle 15.
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In use in the internal vacuum mode, a surface cleaning
apparatus 1 in accordance with the present invention is
placed upon a surface to be cleaned, such as a carpet, the
motor is energised to rotate the brush assembly and the
internal second suction creating means 17 is also
energised. The brush arrangement 27 is rotated to sweep
debris from the surface to be cleaned as described for the
external vacuum mode.
As shown in Figure 4, vacuum created within the debris
retrieval body by the internal second suction creating
means 17 causes debris to pass through the inlet aperture
75 of the first elongate chamber 69 into the duct 73 via
the outlet 71 provided in the rear wall of the elongate
chamber 69. The duct 73 transfers the debris, in the
direction of arrow 315, from the inlet aperture 75 beneath
the first intermediate compartment 7 to the cyclonic
separator 57. In the cyclonic separator 57 the fine
particles of dust are separated from the air stream and
deposited, via the truncated conical end 61 of the cyclone
body into the second rear compartment 13.
It should be appreciated that the apparatus 1 can be used
in both the internal vacuum mode and the external vacuum
mode simultaneously. As the brush arrangement 27 is rotated
to sweep debris from the surface, the debris is propelled
up and over the inclined wall 39 and conveyed directly into
the first intermediate compartment 7 where it is
temporarily stored. Simultaneously, debris that is not
swept up and propelled into the first intermediate
compartment 7 by the brush arrangement 27 is drawn through
the inlet aperture 75 into the first elongate chamber 69 by
the suction created by the internal second suction creating
means 17 and is drawn through the inlet aperture 85 into
the second elongate chamber 79 by the suction created by
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the external first suction creating means. The two portions
of debris removed by suction means follow separate and
distinct pathways 313 and 315 through the apparatus 1 (as
shown in Figure 4). The two portions of debris removed by
suction means also follow separate and distinct pathways
from the pathway 311 of the debris removed from the surface
by the rotatable brush arrangement.
There is no connection pathway between the first
intermediate compartment 7, the duct 73 between the first
chamber 69 and the second suction creating means 17, and
the duct 83 between the second chamber 79 and the first
suction creating means that would enable debris in the
first intermediate compartment 7 to be conveyed towards
either of the suction creating means. As such, there is no
possibility that the debris collected during use of the
apparatus in the sweeper mode can be drawn towards either
the first or the second suction creating means and cause a
blockage.
Although the nozzles in the form of inlet apertures 75, 85
have been described as being provided rearward of the brush
assembly, it should be appreciated that at least one of the
inlet apertures could be provided forward of the elongate
brush assembly with associated ducting passing over or to
the side of the front compartment.
It should also be appreciated that, although a single
removable plate covering the inlet apertures 75, 85 has
been described, either of the inlet apertures 75, 85 could
be uncovered. It should also be appreciated that the inlet
75 of the first chamber 69 and the inlet aperture 85 of the
second chamber 79 may be covered by separate removable
plates.
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It should be appreciated that debris can be collected
directly in a non-removable form of the first intermediate
compartment and/or the second rear compartment wherein a
closure is provided which can be opened for the emptying of
debris therein.
It should also be appreciated that debris picked up by the
brush arrangement and debris picked up by the internal
suction generating means can be collected into two separate
collecting means of a single collection body, where the two
collecting means are sealed relative to each other to
maintain suction within the apparatus.
Although an auxiliary brush 41 is described, it should be
appreciated that a surface cleaning apparatus in accordance
with the present invention need not have the auxiliary
brush.
Although the means of creating suction within a surface
cleaning apparatus in accordance with the present invention
has been described hereinbefore as a cyclonic system, it
should be appreciated that other methods of creating
suction within a surface cleaning apparatus, known to a
person skilled in the art, could be used, for example a
suction creating assembly using a porous bag for the
accumulation of debris.
