Note: Descriptions are shown in the official language in which they were submitted.
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VACUUM CLEANER
The present invention relates to vacuum cleaners, and relates particularly,
but
not exclusively to hand-held battery operated vacuum cleaners.
Hand-held vacuum cleaners are known in which a fan displaces air out of vents
in a housing of the vacuum cleaner, as a result of which suction is produced,
drawing
dirty air into the housing through inlets, and the dirty air is then filtered
between the
inlets and the fan.
It is generally the practice to vent the exhausted air through vents located
on
the sides, at the rear and/or on top of the housing of the vacuum cleaner. fn
the field
of hand-held battery operated vacuum cleaners, it is generally considered
necessary
to vent the exhausted air through the top, rear or sides of the housing, since
it is
generally believed that air exhausted through the bottom surface of the
housing
would disturb dirt particles on the dirty surface being cleaned.
However, locating exhaust vents at the rear, on the sides or on the top of the
vacuum cleaner housing has the disadvantage that when these vents are located
near to the handle, which in a compact hand-held vacuum cleaner is generally
inevitably the case, the air stream is blown on to the hand of the user. This
has
proven irritating to users, in particular when the vacuum cleaner is used for
long
periods of time. Locating the exhaust vents in the top or rear of the housing
has the
further disadvantage that the exhaust air flow is often directed into the face
of the
user. This is again irritating and can be dangerous in a dusty environment
where
dust particles are more likely to be caught in the eye of a user when an
increased air
flow is blowing across the user's face.
Preferred embodiments of the present invention seek to overcome the above
described disadvantages of the prior art.
According to the present invention there is provided a vacuum cleaner
comprising:-
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a housing having at least one inlet adjacent an end portion of said housing
for
intake of air and at least one first outlet in a bottom surface of said
housing for
exhaust of air;
suction means for causing air to flow from at least one said inlet to at least
one
said first outlet; and
first filter means for removing particles larger than a first predetermined
size
from air flowing from at least one said inlet to at least one said first
outlet, wherein the
or each said first outlet is adapted to direct air from the housing in a
direction away
from the or each said inlet.
By providing a vacuum cleaner having at least an outlet on the bottom surface
of the housing such that the exhaust air is directed through the outlet away
from the
or each inlet, this provides the advantage that exhaust air from the vacuum
cleaner is
not blown onto the face and hands of the user, thus minimising discomfort to
the
user, while also not disturbing dirt particles on the surface which is being
cleaned.
This result is highly surprising, since it is generally considered impossible
by persons
skilled in the art to vent exhaust air through a bottom surface of the housing
without
disturbing dirt on the surtace being cleaned.
The vacuum cleaner may further comprise second filter means for removing
particles larger than a second predetermined size, smaller than said first
predetermined size, from air flowing through at least one said first outlet.
The second filter means may be provided in at least one said first outlet.
By passing the exhaust air through a second filter means located in at least
one
said first outlet, this provides the advantage that the second filter means
acts as a
baffle, thereby slowing the speed of the stream of air and further reducing
the
likelihood of the air disturbing particles on the surface which is being
cleaned.
The vacuum cleaner may further comprise a plurality of slats arranged adjacent
at least one said first outlet for directing air passing through said first
outlet away
from the or each said inlet.
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The vacuum cleaner may further comprise at least one second outlet for
enabling air flowing from said suction means to the or each said second outlet
to cool
a motor of the vacuum cleaner.
At least one said second outlet may be provided in a side surface of the
housing.
In a preferred embodiment, the housing comprises a plurality of housing parts,
and air flows to at least one said second outlet in use via at least one gap
between
two said housing parts.
By enabling air to flow to at least one said second outlet via at least one
gap
between two said housing parts, this provides the advantage of enabling
leakage of
air flow from the main air flow path to be utilised without the necessity of
forming
complex pathways. Furthermore, the rate of secondary air flow used to cool the
motor is generally sufficiently small that it can be vented out of the top or
side
surfaces of the housing without causing irritation to the user.
A preferred embodiment of the present invention will now be described, by way
of example only and not in any limitative sense, with reference to the
accompanying
drawings, in which:
Figure 1 is a sectional view of a housing of a vacuum cleaner embodying the
present invention, with two housing parts thereof separated and a nose portion
removed;
Figure 2 is a perspective view of part of the vacuum cleaner of Figure 1 with
the
nose portion attached;
Figure 3 is a detailed perspective view of part of the vacuum cleaner of
Figure
2; and
Figure 4 is a schematic view of the vacuum cleaner of Figures 1 to 3 in use.
Referring to Figures 1 to 3, a vacuum cleaner 2 has a housing 4 comprising a
body portion 6 and a removable nose portion 8. The body portion 6 is formed
from
co-operating injection moulded clam-shell halves 10, 12 and has a grill 14
defining an
air inlet and an aperture 16 for accommodating slats 18 defining primary air
outlets
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20, The primary air outlets 20 are defined in a bottom surface of the body
portion 6
and direct air downwardly and rearwardly of the housing 4. The body portion 6
also
defines a handle 22 in an upper part thereof.
An electric motor 24, powered by a rechargeable battery (not shown) is
provided in the body portion 6 and drives a fan 26 such that the fan 26
displaces air
radially outwards and out of primary outlets 20 and draws air axially inwards
through
grill 14. Secondary outlets 28 are also provided in side surfaces of the body
portion 6
such that a small proportion of air displaced outwards by the fan 26 is able
to pass,
via leakage between the two clam-shell halves 10,12, out of the secondary
outlet 28
to cool the motor 24.
The slats 18 are provided in a hinged door 30 mounted to the body portion 6 to
close aperture 16, and a fine filter covers the primary outlets 20, the filter
comprising
a filter medium 32 which is held in a compressed manner between hinged door 30
and a grill 34 located in the aperture 16. The body portion 6 is also provided
with
electrical contacts 36 for enabling recharging of the rechargeable battery
which
drives the motor 24.
The nose portion 8 defines an inlet 38 for dirty air and contains a filter
(not
shown) which comprises a coarse filter and a fine filter, for removing dirt
from air
flowing from the inlet 38 to the grill 14 as a result of suction generated by
the fan 26.
The construction of the filter located within the nose portion 8 will be
familiar to
persons skilled in the art and will therefore not be described in further
detail.
The operation of the vacuum cleaner 2 will now be described with reference to
Figures 1 to 4.
Vacuum cleaner 2 is oriented in the manner shown in Figure 4 over a dirty
surface 40 to be cleaned. The motor 24 is actuated by means of a suitable
switch
(not shown) provided adjacent the handle 22 on body portion 6, as a result of
which
the fan 26 draws dirty air into the inlet 38 of the nose portion 8 and through
the filter
in the nose portion. The filtered air is drawn through grill 14 and displaced
radially
outwards by the fan 26, most of the air passing out of the primary outlets 20
in such a
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manner that the air is displaced generally in the direction of arrow D in
Figure 4. As a
result, the air is not vented onto the face and hands of the user, and at the
same time
avoids disturbing dirt on the surface 40 to be cleaned. A small amount of the
air
displaced radially outwards by the fan 26 passes between the clam-shell halves
10,
5 12 and out of the secondary outlets 28 in the side surfaces of the body
portion 6. As
a result, the motor 24 is cooled, but the rate of air flow out of the
secondary outlets
28 is insufficient to cause irritation to the user.
It will be appreciated by persons skilled in the art that the above embodiment
has been described by way of example only and not in any limitative sense, and
that
various alterations and modifications are possible without departure of the
scope of
the invention as defined by the appended claims.
