Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TITLE: HAND VACUUM CLEANER WITH A REMOVABLE CYCLONE UNIT
FIELD
The specification relates to vacuum cleaners, and particularly, to
cyclonic hand vacuum cleaners. More specifically, the specification relates to
hand vacuum cleaners having a removable dirt chamber.
INTRODUCTION
The following is not an admission that anything discussed below is
prior art or part of the common general knowledge of persons skilled in the
art.
PCT publication WO 2008/009890 (Dyson Technology Limited)
discloses a handheld cleaning appliance comprising a main body, a dirty air
inlet,
a clean air outlet and a cyclonic separator for separating dirt and dust from
an
airflow. The cyclone separator is located in an airflow path leading from the
air
inlet to the air outlet. The cyclonic separator is arranged in a generally
upright
orientation (i.e., the air rotates about a generally vertical axis in use). A
base
surface of the main body and a base surface of the cyclonic separator together
form a base surface of the appliance for supporting the appliance on a
surface.
See also PCT publication WO 2008/009888 (Dyson Technology Limited) and
PCT publication WO 2008/009883 (Dyson Technology Limited).
United States patent 7,370,387 (Black & Decker Inc.) discloses a
hand-holdable vacuum cleaner that uses one or more filters and/or cyclonic
separation device, and means for adjusting an angle of air inlet relative to a
main
axis of said vacuum cleaner. In particular, the vacuum cleaner further
comprises
a rigid, elongate nose having the air inlet at one end thereof, the nose being
pivotal relative to a main axis of the vacuum cleaner through an angle of at
least
135 degrees.
SUMMARY
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The following introduction is provided to introduce the reader to the
more detailed discussion to follow. The introduction is not intended to limit
or
define the claims.
According to one broad aspect, a hand vacuum cleaner is disclosed
having a simplified structure for emptying the vacuum cleaner. The hand vacuum
cleaner is preferably a cyclonic vacuum cleaner wherein the dirt chamber is
removable as a sealed unit from the vacuum cleaner. The dirt chamber may be
part of a cyclone (e.g., the lower portion of a cyclone chamber) and removable
with the cyclone. Alternately, the dirt chamber may be external to the cyclone
chamber and removable from the hand vacuum cleaner by itself. In either case,
the dirt collection chamber is closed (other than, e.g., an air inlet, an air
outlet, a
dirt outlet) when removed from the hand vacuum cleaner. The dirt chamber may
be openable, such as by an openable or removable lid or door. Accordingly,
dirt
collected in the chamber may be transported to a disposal site (e.g., a
garbage
can) without the dirt being dispersed as the dirt collection chamber is
conveyed
to the disposal site.
Another advantage of this design is that the dirt chamber, and the
cyclone if removed with the dirt chamber, may be washed or immersed in water
without concern that the motor of the hand vacuum cleaner may be damaged.
The portion of the hand vacuum cleaner may be dried and then remounted to the
hand vacuum cleaner so that the hand vacuum cleaner is then ready for further
use.
In some examples, the hand vacuum cleaner may comprise an air
flow passage extending from a dirty air inlet to a clean air outlet with a
first
cyclone unit positioned in the air flow passage. The first cyclone unit may
comprise at least one cyclone and at least one dirt collection chamber. The
dirt
collection chamber may be a portion of the cyclone casing (e.g., a lower
portion
of a cyclone chamber or a chamber external to the cyclone casing and connected
in flow communication with the cyclone chamber via a dirt outlet of the
cyclone
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chamber. The dirt collection chamber is removable frorb the surface cleaning
apparatus as a sealed unit for emptying. A suction motor is positioned in the
air
flow passage.
In some examples, the dirt collection chamber is removable from
the hand vacuum cleaner with the first cyclone unit. The first cyclone unit
may be
sealed when removed from the hand vacuum cleaner other than fluid flow
passages leading to and from the first cyclone unit.
In some examples, the first cyclone unit has a single cyclone and
the dirt collection chamber is positioned exterior to the single cyclone. The
cyclone and the dirt collection chamber may comprise a one-piece assembly,
and may be integrally formed. For example, the dirt chamber and the cyclone
chamber may be produced in a single mold, together optionally with an end
wall.
The other end, e.g., the bottom of the dirt chamber, may be closed by an
openable door.
In some examples, the hand vacuum cleaner comprises a suction
motor housing, the suction motor is positioned in the suction motor housing,
and
the first cyclone unit is removably mounted to the suction motor housing.
In some examples, the cyclone unit has a first mounting member,
the suction motor housing has a second mounting member, and the first and
second mounting members are rotationally secured together. Preferably, a
bayonet mount is used. However, a screw mount or other means, such as
latches or other hand operable releasable mechanical fasteners, may be used.
In some examples, the at least one dirt collection chamber is
openable when mounted to the hand vacuum cleaner.
In some examples, the hand vacuum cleaner has a front end and a
rear end, the first cyclone unit is positioned forward of the suction motor
housing,
and the at least one dirt collection chamber has an openable door positioned
at
the front end.
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In some examples, the hand vacuum cleaner further comprises an
airflow chamber extending from a dirty air inlet to the cyclone whereinthe
airflow
chamber is removable with the first cyclone unit. The airflow chamber may be
integrally formed as part of the first cyclone unit.
In some examples, the first cyclone unit has a single cyclone and a
single dirt collection chamber. In other examples, the hand vacuum cleaner
further comprises a second cyclone unit downstream from the first cyclone
unit.
It will be appreciated that a hand vacuum cleaner may incorporate
one or more of the features of each of these examples.
DRAWINGS
In the detailed description, reference will be made to the following
drawings, in which:
Figure 1 is a side plan view of an example of a hand vacuum
cleaner;
Figure 2 is a top plan view of the hand vacuum cleaner of Figure 1;
Figure 3 is a front plan view of the hand vacuum cleaner of Figure
1;
Figure 4 is a partially exploded rear perspective view of the hand
vacuum cleaner of Figure 1;
Figure 5 is a partially exploded front perspective view of the hand
vacuum cleaner of Figure 1;
Figure 6 is a cross section taken along line 6-6 in Figure 2; and
Figure 7A is a bottom perspective view of the hand vacuum cleaner
of Figure 1;
Figure 7B is a rear perspective view of the hand-vacuum cleaner of
Figure 1, showing the cyclone unit removed from the hand vacuum cleaner; and,
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Figure 8 is a cross section showing an alternate example of a hand
vacuum cleaner.
DESCRIPTION OF VARIOUS EXAMPLES
Various apparatuses or methods will be described below to provide
an example of each claimed invention. No example described below limits any
claimed invention and any claimed invention may cover processes or
apparatuses that are not described below. The claimed inventions are not
limited
to apparatuses or processes having all of the features of any one apparatus or
process described below or to features common to multiple or all of the
apparatuses described below. It is possible that an apparatus or process
described below is not an embodiment of any claimed invention.
In the drawings attached hereto, the surface cleaning apparatus is
exemplified as used in a hand vacuum cleaner that uses a single cyclone
axially
aligned with a longitudinal axis of the hand vacuum cleaner. It will be
appreciated
that the vacuum cleaner 100 may be of various configurations (e.g., different
positioning and orientation of the cyclone unit and the suction motor and
differing
cyclone units that may comprise one or more cyclones and one or more filters).
Referring to Figures 1 to 7B, a first example of a vacuum cleaner
100 is shown. The vacuum cleaner 100 is a hand vacuum cleaner, and is
movable along a surface to be cleaned by gripping and maneuvering handle 102.
The vacuum cleaner includes an upper portion 104, a lower portion 106, a front
108, and a rear 110. In the example shown, handle 102 is provided at the upper
portion 104. In alternate examples, handle 102 may be provided elsewhere on
the vacuum cleaner 100, for example at the rear 110 and may be of any design.
In the example shown, the vacuum cleaner 100 comprises a nozzle
112 and a cyclone unit 114, which together preferably form a surface cleaning
head 116 of the vacuum cleaner 100. In the example shown, the surface
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cleaning head 116 is preferably provided at the front 108 of the vacuum
cleaner
100.
Nozzle 112 engages a surface to be cleaned, and comprises a dirty
air inlet 118, through which dirty air is drawn into the vacuum cleaner 100.
An
airflow passage extends from the dirty air inlet 118 to a clean air outlet 120
of the
cleaner 100. In the example shown, clean air outlet 120 is preferably at the
rear
110 of the cleaner 100.
Cyclone unit 114 is provided in the airflow passage, downstream of
the dirty air inlet 118. In the example shown, the cyclone unit 114 is a one
piece
assembly comprising one cyclone 122, and one dirt collection chamber 124,
which are preferably integrally formed. In alternate examples, the cyclone
unit
110 may include more than one cyclonic stage, wherein each cyclonic stage
comprising one or more cyclones and one or more dirt chambers. Accordingly,
the cyclones may be arranged in parallel and/or in sequence. Further, in
alternate examples, the cyclone 122 and dirt collection chamber 124 may be
separately formed.
In the example shown, the nozzle 112 is positioned at the lower
portion 106 of the vacuum cleaner 100. Preferably, as exemplified, nozzle 112
is positioned at the bottom of the vacuum cleaner 100, and, preferably,
beneath
the cyclone unit 114. However, it will be appreciated that nozzle 112 may be
connected to the cyclone unit or dirt collection chamber at alternate
locations.
Preferably, as exemplified, nozzle 112 may be on lower surface
157 of cyclone unit 114. In a particularly preferred design, the upper wall of
the
nozzle may be a lower wall of the cyclone unit 114. As shown in Figure 6, dirt
chamber 124 surrounds the lower portion of cyclone 122. Accordingly, the upper
wall of nozzle 112 may be part of the lower wall of the dirt chamber. It will
be
appreciated that if dirt chamber 124 does not extend around the lower portion
of
cyclone 122, then the upper wall of nozzle 112 may be part of a lower wall of
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cyclone 122. In alternate embodiments, nozzle 112 and cyclone 122 or dirt
chamber 124 need not have a common wall.
Preferably, in the example shown, the nozzle 112 is fixedly
positioned at the lower portion 106 of the vacuum cleaner 100. That is, the
nozzle 112 is not movable (e.g., rotatable) with respect to the remainder of
the
vacuum cleaner 100, and is fixed at the lower portion 106 of the vacuum
cleaner
100.
As shown in Figures 3 and 5, nozzle 112 has a width WN, and
cyclone unit 114 has a width Wc. In the example shown, WN, and We are about
the same. An advantage of this design is that the nozzle 112 may have a
cleaning path that is essentially as wide as the hand vacuum itself.
Preferably, nozzle 112 comprises an airflow chamber 136 wherein
at least a portion, and preferably a majority, of the lower surface of the
chamber
is open. Such a design is exemplified in Figure 7A wherein nozzle 112
comprises
an upper nozzle wall 126. In the example shown, the upper nozzle wall 126
comprises a portion 119 of a wall 115 of the cyclone unit. Accordingly, nozzle
112 is integral with cyclone unit 114.
In an alternate design as exemplified by Figure 8, nozzle 812
comprises a lower wall 837, which closes lower end 834. Accordingly, nozzle
112
may be of various designs and may be an open sided passage or a closed
passage. In either embodiment, it will be appreciated that nozzle 112 may be
mounted or provided on cyclone unit 114 and as exemplified on a lower portion
of the dirt collection chamber so as to be removable with the dirt collection
chamber.
Preferably, if nozzle 112 is an open sided passage, one or more
depending walls 128 extend downwardly from the upper nozzle wall 126. The
depending wall is preferably generally U-shaped. In one embodiment, a
depending wall is provided rearward of opening 138. In other embodiments,
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depending walls may alternately or in addition be provided on the lateral
sides of
opening 138. It is preferred that depending walls are provided on each lateral
side of opening 138 and rearward thereof. Further, depending walls 128 may
extend a substantial distance to the front end 108 and, preferably,
essentially all
the way to front end 108. The depending walls may be continuous to define a
single wall as shown, or may be discontinuous. The depending walls are
preferably rigid (e.g., integrally molded with cyclone unit 114). However,
they
may be flexible (e.g., bristles or rubber) or moveably mounted to cyclone unit
114
(e.g., hingedly mounted).
Preferably, the lower end 132 of depending wall 128 is spaced
above the surface being cleaned when the hand vacuum cleaner is placed on a
surface to be cleaned. As exemplified in Figure 6, when vacuum cleaner 100 is
placed on a floor F, lower end 132 of depending wall 128 is spaced a distance
H
above the floor. Preferably distance H is from 0.01 to 0.175 inches, more
preferably from 0.04 to 0.08 inches.
The height of the depending wall (between upper nozzle wall 126
and lower end 132) may vary. In some examples, the depending wall may have
a height of between about 0.05 and about 0.875 inches, preferably between
about 0.125 and about 0.6 inches and more preferably between about 0.2 and
about 0.4 inches. The height of depending wall may vary but is preferably
constant.
As exemplified, the open end of the U-shape defines an open side
130 of the nozzle 114, and forms the dirty air inlet 118 of the cleaner 100.
In the
example shown, the open side 130 is provided at the front of the nozzle 114.
In
use, when optional wheels 135 are in contact with a surface, the open side 130
sits above and is adjacent a surface to be cleaned (e.g. floor F). As
mentioned
hereinabove, preferably, lower end 132 of depending walls 128 is spaced above
floor F. Accordingly, some air may enter nozzle 114 by passing underneath
depending wall 132. In such a case, the primary air entry to nozzle 114 is via
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open side 130 so that dirty air inlet 118 is the primary air inlet, with a
secondary
air inlet being under depending wall 128.
In the example shown, the lower end 132 of the depending wall
128 defines an open lower end 134 of the nozzle 114. The open lower end 134
preferably extends to the front 108 of the cleaner 108, and merges with the
open
side 130. In use, the exemplified nozzle has an open lower end 134 that faces
a
surface to be cleaned.
In the example shown, a plurality of wheels 135 are mounted to the
depending wall 128, and extend lower than the lower end 132 of the depending
wall 128. Accordingly, in use, when wheels 135 are in contact with a surface,
the
lower end 132 of the depending wall 128 is spaced from the surface to be
cleaned, and the space between the lower end of the depending wall 128 and the
surface to be cleaned form the secondary dirty air inlet to the vacuum cleaner
100. It will be appreciated that wheels 135 are optional. Preferably, wheels
135
are positioned exterior to the airflow path through nozzle 112, e.g.,
laterally
outwardly from depending wall 128. Preferably a pair of front wheels 135 are
provided. Preferably, the wheels are located adjacent front 108. Optionally,
one
or more rear wheels 108 may be provided. In an alternate embodiment, no
wheels may be provided.
The upper nozzle wall 126, depending wall 128, and open lower
end 134 of the nozzle 112 define the open sided airflow chamber 136 of the
nozzle. In use, when wheels 135 are in contact with a horizontal surface, the
nozzle 112 and the airflow chamber 136 extend generally horizontally, and
preferably linearly along a nozzle axis 113 (see Figure 7A).
An opening 138 is provided in the upper nozzle wall 126, and is in
communication with the airflow chamber 136. Opening 138 may be of any size
and configuration and at various locations in upper nozzle wall 126. In use,
when
wheels 135 are in contact with a surface, the opening 138 faces a surface to
be
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cleaned, air enters the dirty air inlet 118, passes horizontally through the
airflow
chamber 136, and passes into the opening 138. Opening 138 is in
communication with a cyclone inlet passage 139, which is in communication with
a cyclone air inlet 140 of cyclone 122.
Cyclone 122 may of any configuration and orientation. Preferably,
cyclone 122 comprises a chamber wall 142, which in the example shown, is
cylindrical. The cyclone chamber is located inside chamber wall 142. The
cyclone
122 extends along an axis 123, which, in the example shown, is preferably
parallel to the nozzle axis, and preferably extends generally horizontally
when
cleaner 100 is in use and wheels 135 are seated on a surface. Cyclone 122 has
a front end 196, which is towards, and preferably at the front end 108 of the
hand
vacuum cleaner and a rear end 198. The cyclone 122 has an air inlet 140 and
an air outlet 145 which, preferably are at the same end of cyclone 122 and a
dirt
outlet is preferably provided at the opposite end. Preferably the air inlet
and the
air outlet are distal to front end 108 and a dirt outlet is proximate the
front end
108. The cyclone air inlet and cyclone air outlet may be of any configuration
known in the art and the cyclone air outlet may be covered by a screen or
shroud
or filter as is known in the art.
As exemplified, the cyclone air inlet 140 is defined by an aperture in
the chamber wall 142. As can be seen in Figure 5, the inlet passage 139 is
configured such that air enters the cyclone 122 in a tangential flow path,
e.g.,
passage 139 may be arcuate. The air travels in a cyclonic path in the cyclone,
and dirt in the air is separated from the air. The air exits the cyclone via
an outlet
passage 144, through outlet 145. Outlet 145 is defined in a rear wall 179 of
the
cyclone unit 114.
As exemplified in Figure 6, a plate 174 may be provided adjacent
outlet passage 144, spaced from and facing the inlet 176 to outlet passage
144.
Plate 174 may be mounted to cyclone 122 via legs 178. In the example shown,
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plate 174, and legs 178 form an assembly 182 that is removably mounted in
cyclone 122. In some examples, a screen may be mounted around legs 178.
The dirt that is separated from the air exits the cyclone via dirt
outlet 146, and enters dirt collection chamber 124. Dirt collection chamber
124
may be any dirt collection chamber. Preferably, as exemplified, dirt outlet is
at
the front 196 of the cyclone 122, and further, is at the front end 108 of the
cleaner
100. The dirt collection chamber may be internal or external to the cyclone
chamber. Preferably, as exemplified, the dirt collection chamber is external.
The
dirt collection chamber may be in communication with the cyclone chamber by
any means known in the art. Accordingly, one or more dirt outlets may be
provided. Preferably, the dirt outlet is at the end opposed to the air inlet
and,
preferably, the dirt outlet is at the front end 108. Preferably, the dirt
outlet is at the
end opposed to the air inlet and, preferably, the dirt outlet is at the front
end 108
In the example shown, dirt collection chamber 124 preferably
comprises two portions. A first portion 148 is provided immediately adjacent
the
dirt outlet 146, and is at the front 108 of the cleaner 100. A second portion
150 is
concentric with the cyclone 122. A lower portion 152 of the second portion 150
is
below the cyclone. As exemplified, nozzle 112 is positioned below first
portion
148, and lower portion 152. Accordingly, dirt chamber 124 may comprise an
annular chamber surrounding the cyclone 122.
A separation plate 154 may be provided in the dirt collection
chamber 124, adjacent the dirt outlet 146, and in facing relation to the dirt
outlet.
The separation plate 154 aids in preventing dirt in dirt collection chamber
124
from re-entering cyclone 122. Preferably, plate 154 is spaced from dirt outlet
146
and faces dirt outlet 146. Plate 154 may be mounted by any means to any
component in cyclone unit 114. As exemplified, the separation plate is mounted
on an arm 156, which extends from a front wall 158 at the front 108 of the
cleaner 100.
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Cyclone unit 114, or dirt collection chamber 124 if it is removed by
itself, may be emptied by any means known in the art. For example, one of the
ends of the cyclone unit 114 may be openable. In an embodiment, an openable
door may be positioned at the front end of the vacuum cleaner and preferably
comprises a front wall thereof. The door may be opened while the cyclone unit
or
the dirt collection chamber 124 is mounted to the vacuum cleaner. Alternately,
or
in addition, the door may be opened when the cyclone unit or the dirt
collection
chamber 124 has been removed from the vacuum cleaner. The door may be
openably mounted to the cyclone unit, dirt collection chamber 124 or another
portion of vacuum cleaner 100 by any means known in the art. For example, one
or more latches 159 may secure the door in position. Alternately, the door may
be opened, e.g., pivoted open, and then optionally removable..
As exemplified in Figures 4 and 5, front wall 158 is pivotally
mounted to the cyclone unit wall 115 and serves as an openable door of the
dirt
chamber 124, such that dirt collection chamber 124 is openable, and dirt
collection chamber 124 may be emptied. The dirt collection chamber is
therefore
preferably openable both when the dirt collection chamber is mounted to the
hand vacuum cleaner, or when it is removed, as will be described hereinbelow.
When front wall 158 is pivoted away from the remainder of the cyclone unit
114,
separation plate 154 and arm 156 also pivot away from the remainder of the
cyclone unit. A latch 159 is provided, which secures front wall 158 to wall
115.
In alternate examples, front wall 158 may be removable from cyclone unit wall
115, or the rear wall 179 of the cyclone unit 114 may be openable.
The rear portion of the dirt collection chamber 124 may be closed
by wall 179.
The clean air exiting cyclone 122 passes through outlet 145 of
outlet passage 144, exits surface cleaning head 116, and passes into the
cleaner
body 160. In the example shown, the cleaner body 160 is positioned rearward of
the surface cleaning head 116. The cleaner body comprises a suction motor
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housing 168, which houses an optional pre-motor filter 162, a suction motor
164
and may house an optional post-motor filter 166.
In the example shown, suction motor housing 168 further houses a
pre-motor filter 162. Pre-motor filter 162 is provided in the airflow path
preferably
adjacent and downstream of the outlet passage 144, and facing the outlet 145.
Pre-motor filter 162 serves to remove remaining particulate matter from air
exiting the cyclone 122, and may be any type of filter, such as a foam filter.
One
or more filters may be used. In the exemplified embodiments, the vacuum
cleaner has a linear configuration If the vacuum cleaner is of a non-linear
configuration, then pre-motor filter 162 need not be located adjacent outlet
passage 144.
Suction motor 164 is provided in the airflow path preferably
adjacent and downstream of the pre-motor filter 162. The suction motor 164 may
be any type of suction motor. The suction motor draws air into the dirty air
inlet
118 of the cleaner 100, through the airflow path past the suction motor 164,
and
out of the clean air outlet 120. The suction motor 164 has a motor axis 165.
In
the example shown, the motor axis 165 and the cyclone axis 123 preferably
extend in the same direction and are preferably generally parallel. In the
exemplified embodiments, the vacuum cleaner has a linear configuration. If the
vacuum cleaner is of a non-linear configuration, then motor 164 need not be
located adjacent pre-motor filter 162.
The cleaner body 160 preferably further comprises a post-motor
filter housing 170. A post motor filter 166 is provided in the post-motor
filter
housing 170. The post motor filter 166 is provided in the airflow path
downstream of, and preferably adjacent, the suction motor 164. Post motor
filter
166 serves to remove remaining particulate mater from air exiting the cleaner
100. Post-motor filter 166 may be any type of filter, such as a HEPA filter.
If the
vacuum cleaner is of a non-linear configuration, then post motor filter 166
need
not be located adjacent suction motor 164.
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Clean air outlet 120 is provided downstream of post-motor filter
166. Clean air outlet 120 may comprise a plurality of apertures formed in
housing 170.
Referring to Figure 7B, the dirt collection chamber 124 is removable
from the hand vacuum cleaner 100 as a sealed unit for emptying. In the example
shown, the cyclone unit 114 comprises the dirt collection chamber 124.
Accordingly, the cyclone unit 114 is removable from the hand vacuum cleaner.
As the cyclone unit 114 is integral with nozzle 112 and airflow chamber 136,
nozzle 112 and airflow chamber 136 are removable from the cleaner 100 with
cyclone unit 114.
As can be seen in Figure 7B, when the cyclone unit 114 is removed
from the hand vacuum cleaner, and particularly from motor housing 168, it is
sealed, except for the fluid flow passages leading to and from the first
cyclone
unit (i.e. opening 138 and outlet 145). That is, wall 179 and/or front wall
158 seal
the cyclone unit 114. In order to empty the dirt collection chamber 124, the
front
wall 158 or the rear wall 179 may be opened, and the dirt may be emptied from
dirt chamber 124.
In order to remove cyclone unit 114 from the surface cleaning
apparatus, the cyclone unit comprises a first mounting member 173, and the
suction motor housing 168 has a second mounting member 175. The first 173
and second 175 mounting members are releasably engageable with each other.
In the example shown, the first 173 and second 175 mounting members
comprise a bayonet mount. In alternate examples, the first and second mounting
members may be another type of mounting member, such as mating screw
threads, magnets, or hand manipulable mechanical fasteners such as latches or
any other type of mounting members.
one or more additional wheels 180 may be mounted to housing
161, preferably at lower portion 106, and may be used in conjunction with
wheels
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135. Preferably, a single rear wheel 180 is provided. Preferably, rear wheel
180
is located on a centre line of the vacuum cleaner and rearward of the
depending
wall 128.
Referring now to Figure 8, in which like numerals refer to like
features, with the first digit incremented to 8 to refer to the figure number,
an
alternate example of a hand vacuum cleaner 800 is shown. In this example,
Cleaner 800 further comprises a second cyclone unit 851
downstream of the first cyclone unit 814, between first cyclone unit 814 and
pre-
motor filter 862. In the example shown, the second cyclone unit 851 comprises
a
plurality of cyclones in parallel. Each of the plurality of cyclones is
parallel to the
first cyclone axis 823.
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