Note: Descriptions are shown in the official language in which they were submitted.
1058810
This invention relates to an apparatus for cleaning a
surface submerged within a liquid. In particular, the invention
relates to an apparatus for automatically cleaning swimming pools.
It is known to provide a suction cleaner connected to a
hose to clean debris from submerged surfaces of a swimming pool.
Such cleaners are usually connected to the intake of a circula-
tion pump by means of a long flexible hose. The cleaner is con-
nected to a pole to enable the cleaner to be moved across the
surface. The area that can be cleaned by such equipment is
necessarily limited by the length of the pole used. Thus large
pools require excessively long poles to enable all areas to be
cleaned.
A further problem with the above apparatus is that the
suction must be limited so that it is possible to move the cleaner
across the surface. Thus the cleaner may not satisfactorily re-
move all the debris.
The cleaners described above also require constant super-
vision in order to manipulate the pole so that cleaning of the
pool becomes a time consuming and laborious procedure.
According to the invention there is provided a cleaning
apparatus' for automatically cleaning a surface submerged in a
liquid, the apparatus including a cleaning head having a peri-
pheral region releasably engageable with the surface to be
cleaned; and a displaceable ballast member which is automatically
; displaced by gravity away from the cleaning head when the peri~
pheral region of the cleaning head is vertically orientated and
the apparatus is tilted over a predetermined degree, and which
automatically returns to its original position closer to the
cleaning head when the peripheral region is horizontally
orientated.
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The suction passages may be linear and may be
de~ined by a rigid material. The passages may have a sui-table
constant cross-sectional area and may be of a suitable length,
dependent on the suction pressure applied to the passages, such
-that the liquid flowing through either of the passages has
sufficient kinetic energy so that when the flow of liquid is
transferred to the other passage, sufficient energy is transferred
to the apparatus to displace it along the surface to be cleaned.
Thus, the means for transferring the liquid flow may be adapted
to suddenly halt the flow of liquid through one passage whe~
transferring the liquid flow. By this means, an impulsive
force i5 applied to the apparatus due to the kinetic energy
of the liquid flowing in the passage. Further, due to the
inertia of the li~uid in the passage to which flow is transferred,
the suction pressure in the head is decreased when the flow of
the liquid is transferred, thereby decreasing the frictional engage-
ment between the head and the surface and allowing the apparatus
to ~e displaced. When the liquid flow increases to its maximum
val~e, the suction pressure increases resulting in the head
gripping the sur~ace.
Con~eniently, the passages may have the same length.
The cleaning head may have a mouth, the region of the head defining
the mouth being the peripheral region of the head referred to
earlier. This peripheral region may be planar so that the
apparatus is particula~ysuitable for cleaning planar surfaces.
With such a planar peripheral region, the axes of the suction
passages may be located parallel to each other at an acute angle,
preferably of 45, to the plane of the peripheral region. The
passages may be oriented in any suitable fashion with respect to
the plane of the peripheral region. For example, the axes of the
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suction passages may be located in a plane perpendicular to the
plane of the peripheral region; or al-ternatively, the passages
may be located adjacent each other in a plane which intersects
the plane of the peripheral region of the cleaning head at +he
same angle as the angle between the axes of the passages and the
plane of the peripheral region.
The means for automatically transferring the
liquid flow from one passage to the other may comprise a flapper
val~e that is pivotally mounted about a pivotal axis to be
sealingly displaceable against valve seats located at the
communication openings. This valve may be adapted so that
liquid flow from the head into one of the passages tends to
displace the valve into sealing engagement with the valve seat
of that passage, simultaneously opening the communication
opening between the other passage and the head. The pivotal
axis may be located either parallel to or at an acute angle to
the plane of the peripheral region. In other words, if the
head is seated on a horizontal surface the valve will be
pivotable in either a vertical or a horizontal plane. In order
to assist in displacing the apparatus, one or both of the valve
seats may be disposed so that when it is struck by the valve, the
apparatus experiences a nett force that has a component parallel
to the plane of the peripheral region, which reinforces the
force exerted on the apparatus due to the kinetic energy o~ the
fluid flowing in its respective passage.
In order to cater for irregularities in the surface
to be cleaned, to cater for curved transition zones between adjacent
planar surface sections, and to assist in the cleaning action, the
-apparatus may have a sealing flange of a flexible material about
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the mouth o~ the cleaning head. This flange may be rotatably
secured to the head. As the suction grip of the head on the
surface is increased by such a flange, a relief opening may be
provided in the head. ~urther, the surface of the flange which
engages the surface to be cleaned may have an abrasive lining or a
brush to assist in cleaning the said surface.
.,
The suction passages may be defined by two tubes,
or by a tube having an internal partition. The ~ree ends o~ the
passages will be connectable to a flexible hose by means of which
a suction pressure may be appiied to the apparatus. These free
ends of the passages that are remote from the head may have a
common suction inlet having a swivelling coupling that is
connectable to the flexible hose.
A regulator valve may also be provided for regulating
the suction pressure.
The centre of gravity of the apparatus may be
located close to the cleaning head. The apparatus may have a
buoyancy member to decrease the effective weight of the apparatus
in the liquid. The buoyancy member may be disposed on the
opposite side to the peripheral region of the head, so that when
the apparatus falls through the liquid onto the sur~ace it is
correctly oriented for the peripheral region to seat on the
surface.
The apparatus may further have means to turn itself
'5 when it climbs a vertical wall, the surface of which is being
cleaned, to prevent the head breaking the surface of the liquid.
Accordingly, the apparatus may include a displaceable ballast
member which is automatically displaced due to the action of gravity
10588~0
away from the cleaning head when the peripheral region of the
cleaning head is vertically oriented and the apparatus is tilted
over a predetermined degree, and which automatically returns to
its original position closer to the cleaning head when the
peripheral region is horizontally oriented. The ballast member
may be a massy ball that is housed in a "V" shaped housing disposed
with its apex towards the cleaning head.
The cleaning apparatus may be partly or entirely
of a mouldable synthetic plastic material. For example, the
cleaning head and the valve may be moulded from polyurethane
or the like.
The apparatus may be particularly adapted to clean
the walls and the floors of the swimming pools. The suction
pressure may then be exerted by a conventional pump utilised
wit~! the swimming pool, the water sucked through the apparatus
being cleaned by the associated filter of the swimming pool.
The invention will now be described, by way of
examples, with reference to the accompanying drawings, in which:-
~ Figure 1 shows a side view of a cleaning apparatus
in accordance with the invention;
Figure 2 shows a sectional longitudinal view of
the cleaning apparatus, along line II-II in Figure l;
Figure 3 shows a further longitudinal sectional
view of the apparatus along line III-III in Figure 2;
~25 Figure 4 shows a side view of a further embodiment
of a cleaning apparatus in accordance with the invention; and
Figure 5 shows a longitudinal sec-tional view, of
this further embodiment, along line V-V in Figure 4.
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1058810
R`eferring initially to Figures 1, 2 and 3, a
c:Leaning apparatus ~or automatically cleaning the walls and the
floor of a swimming pool (not shown) is referred to generally
by reference numeral 10. The apparatus 10 basically comprises
a hollow cleaning head 12 -that is in suction communication with
-two suction passages 14.1 and 14.2 and a flapper valve 16 -that
is pivotally displaceable to repeatedly automatically transfer,
in operation, flow of water from the head 12 to one passage
14.1, 14.2 or the other.
The head 12 is formed from three parts, a body member
18, a base member 20 and an intermediate flow directing member 22.
The base member 20 is hollow and has a planar peripheral region
20.1 which defines the mouth 24 of the head 12~ This peripheral
region 20.1 seats in use against the floor or wall of the swimming
pool, due to the suction pressure in the head 12, as will be
explained hereinafter. The body member 18 is also hollow to
define a head chamber 26 which opens into two bores 28. At
the entrances to these bores 28, from the head chamber 26, are
provided valve seats 30 against which the valve 16 seats to close
off the bores 28 from the head chamber 26. The head chamber 26
is in communication with the mouth 24, defined by the base
! member 20, via a flow direc-ting opening 3~ provided in the
intermediate member 22. This opening 3~ is located such that
water that flows from the mouth 24 through the chamber 26 into
~5 one of the bores 28 (the other being closed by the valve 16)
causes the valve 16 to be operated to close the bore 28 that is
open at -that time, -thereby to switch the flow of water from one
bore 28 to the other. The base member 20 has a lip 32 adjacent
the peripheral region 20.1, to locate and retain a flexible
~058810
sealing flange ~4. Conveniently, the base member 20 is circular
so that the sealing flange 34 is rota-table about it, being
retained by the lip 32. In order to relieve the suction force
with which the load 12 would grip the floor or wall of the
swimming pool, relief openings 36 are provided in the side wall
of the base member 20.
As can be seen in Figure 2, the valve 16 is triangular in
cross-section, the apex being received in a recess 38 in the
body member 18, that is located between the valve seats 30. This
o recess 38 locates the valve 16 such that it is pivotally
displaceable from and against one valve seat 30 to the other.
,,
The suction passages 14.1 and 14.2 are defined by rigid
linear pipes 40 that at one end are sealingly secured in the
bores 28 in the body member 18. The bores 28 are such that the
pipes 40 are parallel to each other and at an angle of 45 to
the plane defined by the peripheral region 20.1. Further, the
pipes 40 are adjacen-t each other in a plane that is perpendicular
to the plane of the peripheral region 20.1. Thus, if the
peripheral region 20.1 was to be seated against a horizontal
o floor section of the swimming pool, the pipes 40 would be above
and below each other. Similarly, the valve 16 is pivotable
about an axis that is parallel to the plane of the peripheral
region 20~1, to be movable in a vertical direction.
As will be clearly seen in Figure 2, the valve seats
~0 are such that when first and then the other is struck by the
valve 16, the body member 18 experiences a driving force that has
a nett component in a direction parallel to the plane of the
peripheral region 20.1 towards the side to which the pipes 40
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105881V
are angled, as shown by the arrow 50.
The other ends of the pipes 40 are secured to a junction
member 42. The junction member 42 has two bores 44 at one end,
in which the pipes 40 are received, .~hich join together in a
single bore 46 at the other end of the junction member 42. At
this end, the junction member 42 has a swivel coupling 48 that
is internally screw-threaded and which is attachable to a spiral
wound flexible hose (as shown in Figure 5).
The apparatus 10 is connected to the pump of the swimming
pool by means of this hose. In some cases, depending on the
suction pressure which may be developed by the pump, a by-pass
valve (not shown) may be provided to regulate the suction pressure
applied to the apparatus 10.
The apparatus 10 further has a buoyancy member 52 secured
to the dorsal pipe 40 so that when the apparatus 10 falls to the
floor of the swimming pool it assumes the correct attitude for the
mouth 24 to seat against the floor. A displaceable ballast
member, in the form of a lead ball 54, is also provided. The
ball 54 is constrained to be movable in the arms of a "V"-shaped
housing 56 that is mounted between the pipes 40 with the apex of
the "V~' towards the head 12.
The operation of the apparatus 10 is as follows:-
Ass~ming that the mouth 24 is seated against the floorof the swimming pool, and a suction pressure is applied at the
entrace bore 46 of the junction member 42 via the swivel coupling
48. Water is sucked through the mouth 24 and the relief openings
36 in the base member 20 of the head 12, through the opening 30
1058810
in the intermediate member 22, through the head chamber 26
past the valve 16, and through one of the passages 14.1 and 14.2.
As the flow of the water will not be such as to keep the valve 16
between the valve seats 30, with both passages ~4.1 and 14.2 open,
the valve 16 will seat against one of the seats 30, most probably
that of the passage 14.2. The suction pressure in the head
12 will hold the apparatus against the floor, and due to the
high speed of flow of the water between the flange 34 and the floor,
dirt and other particles will be dislodged and drawn through
the apparatus 10 to the pump and the associated filter of the
swimmin~ pool. The cleaned water i9 then returned to the
pool in the normal way.
The flow of water through the head chamber 26, past the
va~ e 16, and into the passage 14.1 acts on the valve 16 and
causes it to be displaced awa~ from the valve seat 30 ~or the
passage 14.2 against the valve seat 30 for the passage 14.1.
The flow of water in this passage 14.1 is suddenly stopped.
However, the water flowing in the passage 14.1 had kinetic energy,
which is transferred to the body member 18, and thus the
app~ratus 10, via the valve 16. This kinetic energy will be
transferred as a force directed along the axis of the passage,
and will thus have a vertical component and a horizontal
component in the direction of the arrow 50. Further, as the
flow rate of the water into the head chamber 26 is decreased,
due to the inertia of the water in the passage 14.2,
the suction grip of the head 12 on the floor decreases. As a
result, the apparatus 10 is slightly displaced in the direction
of the arrow 50. As the flow ra-te of the water increases,
the apparatus 10 will tend to experience a downward force in the
opposite direction to the previous force. As this force will tend
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1058810 -`
to increase the frictional grip between the head lZ and the
floor and as the suctionalgrip is increased, the apparatus will
not be displaced in the reverse direction to the arrow 50. The
flow of water through the head chamber 26 causes the valve '~
to be displaced toopen the passage 14.1 and close the passage 14.2.
This again causes the apparatus 10 to be displaced in the
direction of the arrow 50. It will be noted that during this
phase of the operation, as the valve seat 30 for the passage 14.2,
is disposed substantially vertically, when it is struck by the valve
16, a force is exerted on the head 12 whose major component is
in the direction of the arrow 50. This causes the apparatus
10 to be displaced further than when the passage 14.1 is closed,
as in the latter case the action of the valve 16 opposes
displacement of the apparatus 10.
By this means, the apparatus 10 migrates across the
t floor of the swimming pool. When the apparatus 10 reaches a
. wall of the pool, it starts Glimbing it. Due to the weight of
; the hose, the apparatus 10 will be tilted over slightly. If
~; the displaceable~ball 54 were not provided, the apparatus 10
would then tend to run along the wall. However, when the
apparatus tilts over a predetermined amount (determined by the
angle between the arms of the housing 56), the ball 54 rolls
away from its normal position at the apex adjacent the head.
This shifts the centre of gravity of the apparatus 10 and results
in the apparatus 10 migrating down the wall. When the apparatus
10 reaches the floor, the ball 54 rolls back to its normal
position.
By this means the apparatus 10 migrates randomly about
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1058810
the floor and walls of the swimming pool, cleaning them. It
will further be understood that the slight vertical movement
of the apparatus 10 causes the flange 34 to flap. This assists
- in dislodging dirt, algae, leaves, or the like, which are
also taken up on the water flow entering the head 12 through the
relief openings 36.
Referring to Figures 4 and 5, an alternative embodiment
of the apparatus 10.1 is shown. This embodiment is similar to
that described earlier, and is correspondingly referenced. With
this embodiment the passages 14.1 and 14.2 are defined by a rigid
partition 60 in a rigid pipe 62. These passages 14.1 and 14.2
are side-by-side, rather than above and below each other as with
the earlier embodiment. In other words, the passages 14.1 and
14.2 lie in a plane that intersects the plane defined by the
peripheral region 20.1 at the same angle as that at which the
passages intersect the latter plane. Further, the valve 16 is
' pivotal about an axis that is at an acute angle to the plane de-
fined by the peripheral region 20.1, such that the valve 16
moves more from side-to-side than up-and-down as with the earl-
ier embodiment. The operation of this embodiment is substanti-
ally the same as the earlier embodiment, except the striking of
the valve seats 30 by the valve 16 causes the apparatus 10 to
tend to move in a zig-zag fashion.
This embodiment is also different from that described
earlier, in that the flange 34 is attached to the head 12 by
studs 64 and the underneath surface of the flange 34 has pieces
of sandpaper 66 adhered to it. Other supplementary cleaning
devices such as a brush could of course be attached to the under-
side of the flange to assist in the cleaning action.
It will be understood that the kinetic energy that the
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water ir. the passage has will be determined by the rate of
flow of the water and its volume (i.e. its mass)~ The rate
of flow will be determined by the suction pressure applied
to the apparatus, the lengths of the passages, and the resistance
to flow afforded by the head 12 and the passages themselves.
Correspondingly, the volume of the water will be determined
by the length and the cross-sectional area of the passages.
These factors, as well as others such as the minimum depth
~; of the swimming pool, will be considered by those skilled in
the art, in the design of apparatus in accordance with the
invention for particular applic-tions.
., .
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