Field of the invention
[0001] The present invention generally relates to laundry machines, i.e. machines for treating
laundry, such as laundry washing machines (laundry washers) and laundry washing and
drying machines (laundry washer/dryers).
Overview of the related state of the art
[0002] Laundry washers and washer/dryers implement laundry washing cycles that include rinsing
phases, and, possibly, laundry washing cycles that essentially consist in a laundry
rinsing phase alone (possibly followed by a spinning phase).
[0003] A laundry machine shall feature good laundry rinsing performance, because it is important
to ensure that the detergents and other products used to wash the laundry are, as
far as possible, removed from the textiles before they are subjected to drying. At
the same time, the consumption of resources like water and electric energy should
be as limited as possible.
[0004] Manufacturers of laundry machines have been for years developing solutions for reducing
the demand of laundry machines for water and/or electric energy, without negatively
impacting, or possibly even enhancing the laundry washing performance.
[0005] The rinsing phase of a laundry washing cycle is in itself rather water-demanding,
so it needs a careful study.
[0006] EP 629733 discloses a solution consisting in the execution of at least one rinsing cycle effected
in such a way that all the water available in the tank, even if in reduced amount,
is circulated several times in forced fashion through all the laundry, by effecting
one or more short periods, or impulses, of drum rotation at high speed (same speed
of the spinning phase) during the rinsing cycle, in such a way that all the reduced
amount of water available is made to pass through the fabrics several times.
Summary of the invention
[0007] The Applicant has faced the problem of devising a new laundry rinsing method, adapted
to be implemented in laundry washers and washer/dryers without excessive burden, which
improves the laundry rinsing result without impacting, or possibly even reducing,
the demand for resources like water and electric energy.
[0008] According to an aspect of the present invention, there is provided a method of rinsing
laundry in a laundry machine as set forth in independent method claim 1.
[0009] The laundry rinsing method comprises the steps of:
- loading rinsing water into the tub;
- rotating the drum at a first rotation speed while recirculating the rinsing water
present in the tub and spraying the recirculated rinsing water into the drum;
- evacuating the rinsing water present in the tub.
[0010] Before said step of evacuating the rinsing water, the method comprises the steps
of:
- rotating the drum at a second rotation speed for a predetermined first time interval,
said second rotation speed being higher than the first rotation speed and sufficient
to cause the laundry being rinsed to stick against an inner surface of the drum due
to centrifugal force;
- stopping the drum rotation for a predetermined second time interval;
- after said second time interval, discharging from the tub a part of the rinsing water
present in the tub.
[0011] Additional features that are believed to be advantageous or preferential but not
essential are set forth in the dependent method claims.
[0012] In this way, by stopping the drum rotation, the rinsing water with detergents diluted
therein has time to deposit at the bottom of the tub. By subsequently discharging
a part of the rinsing water, a significant part of the detergents residues are also
discharged.
[0013] During said steps of stopping the drum rotation and discharging from the tub a part
of the rinsing water present in the tub, the rinsing water present in the tub is preferably
not recirculated.
[0014] Preferably, during said step of rotating the drum at the second rotation speed, the
rinsing water present in the tub is recirculated and sprayed into the drum. In this
way, the rinsing water hits and penetrates into the laundry being rinsed (which, thanks
to the rotation of the drum, is almost evenly distributed along the periphery of the
drum).
[0015] Said second rotation speed is for example of about 150 RPM. Said first rotation speed
is for example of about 50 RPM.
[0016] Preferably, during said step of rotating the drum at the first rotation speed, the
drum is rotated at least once at an intermediate rotation speed, intermediate between
the first and the second rotation speeds, for example of about 75 RPM.
[0017] During the laundry rinsing phase, said step of rotating the drum at the second rotation
speed may be additionally performed at least once without however being followed by
said steps of stopping the drum rotation and discharging from the tub a part of the
rinsing water present in the tub.
[0018] In an embodiment of the present invention, before said step of evacuating the rinsing
water from the tub, the drum rotation speed is brought to said second rotation speed.
[0019] The drum rotation speed may be kept at the second rotation speed for a time before
starting to evacuate the rinsing water from the tub. The drum rotation is then stopped
after an amount of rinsing water has been evacuated from the tub sufficient to cause
a level of the remaining rinsing water remaining in the tub to be below the bottom
of the drum.
[0020] After having evacuated the rinsing water from the tub, a step of spinning the drum
at a spinning speed higher than said second rotation speed is preferably performed.
[0021] Preferably, the drum is rotated at the first rotation speed alternately clockwise
and counter-clockwise.
[0022] Another aspect of the present invention relates to a laundry washing cycle including
at least one laundry rinsing phase implemented according to the laundry rinsing method
set forth hereabove.
[0023] Still another aspect of the present invention relates to a laundry machine adapted
to implement the laundry rinsing method, or the laundry washing cycle, set forth above.
[0024] The present patent application also discloses a laundry washing method in a laundry
machine comprising a washing tub accommodating a rotatable drum, the method comprising
the steps of:
- before submitting the laundry to a spinning phase to extract water therefrom, and
while in the washing tub there is still water sufficient to cause the laundry in the
drum being wetted, causing the drum to rotate at a speed lower than the rotation speed
in the spinning phase but sufficient to cause the laundry to distribute along the
periphery of the drum due to centrifugal force;
- after a predetermined time of rotation of the drum, starting to evacuate water from
the tub,
- stopping the drum rotation when a level of the water remaining in the washing tub
is below the bottom of the drum.
Brief description of the drawings
[0025] These and other features and advantages of the present invention will be made apparent
by the following detailed description of some exemplary and non-limitative embodiments
thereof, description that will be made more intelligible by the aid of the attached
drawings, wherein:
Figure 1 schematically shows a laundry machine according to an embodiment of the present invention,
adapted to implement a laundry rinsing method according to an embodiment of the present
invention;
Figures 2A, 2B and 2C are time diagrams depicting the evolution in time of some control signals and measured
quantities of the laundry machine while performing a laundry rinsing procedure according
to an embodiment of the present invention.
Detailed description of exemplary embodiments of the invention
[0026] Referring to the drawings, in
Figure 1 there is schematically shown a laundry machine
100, for example a laundry washer (the present invention nevertheless applies as well
to a laundry washer/dryer).
[0027] The laundry machine
100 comprises a cabinet
105 enclosing a washing tub
110 and, rotatably accommodated therein, a perforated laundry drum
115, for containing the laundry to be washed; the drum
115 is caused to rotate by a - preferably electric - motor (not shown).
[0028] The laundry machine
100 has a clean water load system and a waste water/washing liquid discharge system.
[0029] The clean water load system preferably comprises a dosing device,
e.g. an electrovalve,
120, whose inlet is connectable (for example
via a hose) to a water spigot (hose and water spigot not shown). In some embodiments
of the invention, the laundry machine may be equipped with a dosing device adapted
to allow selectively providing, at its outlet, cold water or hot water; for example,
the dosing device may comprise two electrovalves, one connectable to a cold water
spigot and the other connectable to a hot water spigot, or the dosing device may comprise
one electrovalve with one outlet and two inlets, one of which connectable to a cold
water spigot and the other connectable to a hot water spigot.
[0030] A metering device, for example a flowmeter
125, may advantageously be connected to the dosing device
120 (e.g., electrovalve) outlet, for measuring the amount of clean water loaded.
[0031] The loaded water may be caused to pass through a container of detergents
135 and be then supplied to the washing tub
110. A by-pass circuit may be provided, internally or externally to the container of detergents
135, adapted to allow the loaded water to be supplied to the washing tub
110 directly, i.e. without being mixed with one or more detergents contained in the container
135.
[0032] The waste water/washing liquid discharge system may comprise a discharge duct
145, for example at the bottom of the washing tub
110, preferably closable in a selective way by means of a valve
150. Downstream the valve
150, an anti-fluff / anti-clog filter
155 is preferably provided, upstream a discharge pump
160 whose outlet is connected to a discharge hose
165, for example connectable to a drain spigot (not shown).
[0033] A pressure sensor
170 (which may be a pressure switch) may also be provided, adapted to sense the pressure
of the liquid present in the washing tub
110.
[0034] A heater
173 is provided for heating the liquid present within the washing tub
110. The heater
173 may comprise one or more electric resistors, and may conveniently be arranged proximate
to the bottom of the washing tub
110.
[0035] The laundry machine
100 preferably comprises a washing/rinsing liquid recirculation system, comprising a
recirculation pump
175, (a) recirculation conduit(s)
175 and (a) nozzle(s)
180 arranged to spray recirculated washing/rinsing liquid inside the drum
115, for example towards the center thereof.
[0036] The laundry machine
100 is equipped with a control unit,
130, for example a programmable logic control unit
130. The control unit
130 governs the operation of the laundry machine. For example: the control unit
130 may advantageously control the electrovalve
120, possibly on the basis of readings received from the flowmeter
125, when the latter is provided for; the control unit
130 may advantageously control the energization of the heater
173; the control unit
130 may advantageously control the activation/deactivation of the recirculation pump
175 and the discharge pump
160; the control unit
130 may advantageously control the rotation of the drum
115 by the motor. The control unit
130 may advantageously operate taking into account user's settings, like for example
the selection of a particular laundry washing cycle among a plurality of washing cycles
available
(e.g.: cotton, wool, synthetics, etc.).
[0037] Referring now to
Figures 2A - 2C, a rinsing procedure implementing a rinsing method according to an embodiment of the
present invention will be described. The rinsing procedure that will be described
may apply to any one of the rinsing phases of a laundry washing cycle, for example,
albeit not limitatively, to the last rinsing phase of a laundry washing cycle (generally,
but not necessarily, a laundry washing cycle may include more than one rinsing phases),
or to a laundry washing cycle essentially consisting in a laundry rinsing phase alone.
[0038] In the diagrams of
Figures 2A - 2C, the abscissa represents the time, expressed in seconds. In ordinate there are shown:
in all the diagrams, on the left, the level of water inside the tub
110, expressed in millimeters (referred for example to the bottom of the drum
115); in the diagrams of
Figures 2A and
2C, on the right, the rotation speed of the drum
115, expressed in Revolutions
per Minute - RPM. Several curves are depicted in the diagrams of
Figures 2A, 2B and
2C:
- curve A (depicted only in Figure 2A) represents the (incremental) amount of clean water loaded during the rinsing phase
(e.g., as measured by the flow meter 125);
- the square-wave curve B (the dotted line, depicted only in Figures 2A and 2C) represents the ON/OFF status of the recirculation pump 175 (the OFF status is indicated by the value 0);
- curve C (depicted only in Figures 2A and 2B) represents the level of water within the tub 110 (e.g., as measured by the pressure sensor 170);
- curve D (depicted only in Figures 2A and 2C) represents the drum rotational speed as set by the control unit 130;
- curve E (depicted only in Figure 2A) represents the variation of the temperature of the water inside the tub 110;
- curve F (the dotted line visible only in Figure 2B) represents the ON/OFF status of the discharge pump 160 (the OFF status is indicated by the value 0).
[0039] The rinsing procedure can be regarded as (and is better understood if regarded as)
comprising a sequence of stages, for example fourteen stages in the exemplary embodiment
depicted in
Figures 2A - 2C. However, the subdivision of the rinsing procedure in a succession of stages, and
the number and the sequence of stages illustrated in the following, are not to be
construed limitatively, and are just for better intelligibility.
- First stage (Stage 1)
[0040] The rinsing procedure starts by causing the laundry machine
100 to load clean water. The control unit
130 commands the opening of the electrovalve
120, for example for a predetermined time interval, or, in case the flow meter
125 is provided, until the reading of the flow meter
125 itself about the amount of clean water loaded reaches a predetermined value. In the
example of
Figure 2A, the amount of clean water loaded in the first stage is advantageously approximately
20-22 liters; the water may be loaded in one or more shots.
[0041] During the first stage, the drum
115 is caused to rotate; preferably, the rotation speed is kept at a first, low RPM value,
equal for example to approximately 50 RPMs; preferably, the sense of rotation of the
drum is alternately clockwise and counter-clockwise. Also, during the first stage,
the recirculation pump
175 is activated, either for part of the time or continuously. The heater
173 is, for example, kept de-energized (however the heater
173 may also be energized, at least for part of the first stage duration).
[0042] The first stage of the rinsing procedure may for example last about 300 seconds.
This first stage of the rinsing procedure is useful for wetting the laundry to be
rinsed.
- Second stage (Stage 2)
[0043] In the second stage, preferably, the control unit
130 energizes the heater
173, in order to at least slightly heat the rinsing water up. For example, the heater
173 may be kept energized for about 2 minutes. Heating the rinsing water up promotes
the dissolving of detergents that are present in the laundry. During the second stage,
the drum
115 is caused to rotate alternately clockwise and counter-clockwise at the first, low
RPM value
(e.g., about 50 RPMs). Possibly, but not necessarily, during the second stage, for one or
more of the clockwise or counter-clockwise rotation pulses of the drum
115 the rotation speed may be slightly increased to an RPM value of, for example, approximately
75 RPM (in the example of
Figures 2A - 2C, in the second stage of the rinsing procedure, four of the rotation pulses of the
drum are at 75 RPM); for example, the generic clockwise or counter-clockwise drum
rotation pulse at the first RPM value of
e.g. 50 RPM may last about 6 seconds, whereas the generic drum rotation pulse at the increased
RPM value of
e.g. 75 RPM may last about 3 seconds. During the second stage, the recirculation pump
175 is preferably kept activated, at least for part of the time, for recirculating the
rinsing water and spraying it inside the drum, against the laundry to be rinsed.
- Third stage (Stage 3)
[0044] In the third stage of the rinsing procedure, the drum
115 is caused to rotate, preferably alternately clockwise and counter-clockwise, at the
first RPM value,
e.g. 50 RPM, and for one or more of the clockwise or counter-clockwise rotation pulses
the drum
115 may be caused to rotate at an increased RPM value of, for example, approximately
75 RPM (in the example of
Figures 2A - 2C, four rotation pulses are at 75 RPM). For example, the generic clockwise or counter-clockwise
drum rotation pulse at the first RPM value of,
e.g., 50 RPM may last about 6 seconds, whereas the generic drum rotation pulse at the increased
RPM value of,
e.g., 75 RPM, may last about 3 seconds. During the third stage, the recirculation pump
175 is preferably kept activated, to cause recirculation of the rinsing water with spray
thereof inside the drum against the laundry to be rinsed. The duration of this third
stage may be dependant on the overall duration of the rinsing phase; in the example
of
Figures 2A - 2C, the duration of the third rinsing procedure stage is about 3 minutes.
- Fourth stage (Stage 4)
[0045] In the fourth stage of the rinsing procedure, the rotation speed of the drum is increased
to reach a second RPM value (higher than the increased RPM value of,
e.g., 75 RPM), for example of about 150 RPM; for example, the rotation speed increase rate
is of about 5 RPM
per second, so that a time of about 30 seconds is needed to reach the second RPM value.
Since there is water in the tub
110, the drum rotation speed increase rate is deliberately rather slow, in order not to
stress the motor.
[0046] The drum rotation speed is then kept at the second RPM value for a predetermined
time, for example about 20 seconds. The recirculation pump
175 is advantageously kept on, so as to cause recirculation of the rinsing water with
spray thereof inside the drum
115 against the laundry to be rinsed.
[0047] Thanks to the relatively high drum rotation speed
(e.g., 150 RPM), the laundry is caused to more or less stick against the inner wall of the
drum
115 (due to the experienced centrifugal force); thanks also to the fact that there is
a relatively high amount of water in the tub
110, there is a good exchange of water between the laundry and the water in the tub. The
Applicant has found that if, as mentioned, the recirculation pump
175 is preferably kept activated, the thrust of the water sprayed by the nozzle
185 is increased, so that the sprayed rinsing water reaches a longer distance and better
penetrates through the laundry that is stuck against the inner wall of the drum, promoting
the removal of detergents trapped therein, rather uniformly for all the laundry items
being rinsed.
- Fifth stage (Stage 5)
[0048] During the fifth stage, similarly to the third stage, the drum
115 is caused to rotate, preferably alternately clockwise and counter-clockwise, at the
first RPM value,
e.g. 50 RPM, and for one or more of the clockwise or counter-clockwise rotation pulses
the drum
115 may be caused to rotate at the increased RPM value of, for example, approximately
75 RPM (in the example of
Figures 2A - 2C, six rotation pulses are at 75 RPM). For example, the generic clockwise or counter-clockwise
drum rotation pulse at the first RPM value of,
e.g., 50 RPM may last about 6 seconds, whereas the generic drum rotation pulse at the increased
RPM value of,
e.g., 75 RPM may last about 3 seconds. During the third stage, the recirculation pump
175 is preferably kept activated, to cause recirculation of the rinsing water with spray
thereof inside the drum against the laundry to be rinsed.
- Sixth stage (Stage 6)
[0049] The sixth stage may be similar to the fourth stage: the rotation speed of the drum
115 is increased - at a controlled increase rate - to reach a relatively high RPM value,
for example the second RPM value,
e.g. of about 150 RPM; for example, the rotation speed increase rate is of about 5 RPM
per second, so that a time of about 30 seconds is needed to reach the second RPM value.
The drum rotation speed is then kept at the second RPM value for a predetermined time,
for example about 20 seconds. The recirculation pump
175 is advantageously kept on, so as to cause recirculation of the rinsing water with
spray thereof inside the drum against the laundry to be rinsed.
[0050] Thanks to the relatively high drum rotation speed
(e.g., 150 RPM), the laundry is again caused to more or less stick against the inner wall
of the drum
115 (due to the experienced centrifugal force); thanks also to the fact that there is
a relatively high amount of water in the tub
110, there is a good exchange of water between the laundry and the water in the tub. The
Applicant has found that if, as mentioned, the recirculation pump
175 is preferably kept activated, the thrust of the water sprayed by the nozzle
185 is increased, so that the sprayed rinsing water reaches a longer distance and better
penetrates through the laundry that is stuck against the inner wall of the drum, promoting
the removal of detergents trapped therein, rather uniformly for all the laundry items
being rinsed.
- Seventh stage (Stage 7)
[0051] During this stage, the control unit
130 stops the motor that causes the drum
115 to rotate. The drum
115 thus stops to rotate. Preferably, the control unit
130 also stops the recirculation pump
175, so as to stop the forced recirculation of the rinsing water with spray thereof inside
the drum against the laundry to be rinsed.
[0052] This stage of the rinsing procedure lasts for a predetermined, relatively short time,
for example 50 seconds. This allows the detergents diluted in the rinsing water depositing
at the bottom of the tub
110 (and in the tub bottom sump). The Applicant has found that by stopping the drum
115, and simultaneously stopping the recirculation pump
175, the residues of detergents in the rinsing water more easily concentrate proximate
to the sump of the tub
110.
- Eighth stage (Stage 8)
[0053] After the stop of the drum
115 rotation and of the recirculation pump
175, the control unit
130 activates the discharge pump
160, for discharging an amount of rinsing water sufficient to remove the detergent residuals
accumulated at the bottom (in the sump) of the tub
110. For example, the discharge pump
160 may be kept activated for a time sufficient to discharge about 1 liter - 1 liter
and a half; for example, a discharge pump activation time of about 6 seconds has been
found to be suitable.
[0054] Optionally, after this stage, a certain additional amount of clean water might be
loaded, for example an amount corresponding to the discharged amount of rinsing water;
this might for example be useful in those cases where the amount of water loaded at
the beginning of the rinsing procedure is relatively small.
- Ninth stage (Stage 9)
[0055] The ninth stage is similar to the fifth stage: the drum
115 is caused to rotate, preferably alternately clockwise and counter-clockwise, at the
first RPM value,
e.g. 50 RPM, and for one or more of the clockwise or counter-clockwise rotation pulses
the drum
115 rotation speed may be increased to an RPM value of, for example, approximately 75
RPM (in the example of
Figures 2A - 2C, three rotation pulses are at 75 RPM). For example, the generic clockwise or counter-clockwise
drum rotation pulse at the first RPM value of,
e.g., 50 RPM may last about 6 seconds, whereas the generic drum rotation pulse at the increased
RPM value of,
e.g., 75 RPM may last about 3 seconds. During the third stage, the recirculation pump
175 is preferably reactivated, to re-start recirculation of the rinsing water with spray
thereof inside the drum against the laundry to be rinsed. The duration of the ninth
stage may be similar to, or lower than (as in the example of
Figure 2), the duration of the fifth stage.
- Tenth stage (Stage 10)
[0056] The tenth stage is similar to the fourth stage: the drum rotation speed is increased
- at a controlled increase rate - to reach the second RPM value, for example of about
150 RPM; for example, the rotation speed increase rate is of about 5 RPM
per second, so that a time of about 30 seconds is needed to reach the third RPM value.
The drum rotation speed is then kept at the second RPM value for a predetermined time,
for example about 20 seconds. The recirculation pump
175 is advantageously kept on, so as to cause recirculation of the rinsing water with
spray thereof inside the drum against the laundry to be rinsed.
- Eleventh stage (Stage 11)
[0057] The eleventh stage is similar to the fifth (and ninth) stage: the drum
115 is caused to rotate, preferably alternately clockwise and counter-clockwise, at the
first RPM value,
e.g. 50 RPM, and for one or more of the clockwise or counter-clockwise rotation pulses
the drum
115 rotation speed may be increased to, for example, approximately 75 RPM (in the example
of
Figures 2A - 2C, three rotation pulses are at 75 RPM). For example, the generic clockwise or counter-clockwise
drum rotation pulse at the first RPM value of,
e.g., 50 RPM may last about 6 seconds, whereas the generic drum rotation pulse at the increased
RPM value of,
e.g., 75 RPM may last about 3 seconds. During the third stage, the recirculation pump
175 is preferably kept activated, to cause recirculation of the rinsing water with spray
thereof inside the drum against the laundry to be rinsed. The duration of the ninth
stage may be similar to the duration of the fifth stage (as in the example of
Figures 2A - 2C), or different (longer or shorter).
- Twelfth stage (Stage 12)
[0058] Similarly to the fourth, sixth and eleventh stages, the drum rotation speed is increased
to reach the second RPM value, for example of about 150 RPM; for example, the rotation
speed increase rate is of about 5 RPM
per second. The drum rotation speed is then kept at the second RPM value for a predetermined
time, for example about 30 seconds. In the twelfth stage the recirculation pump
175 is advantageously turned off.
- Thirteenth stage (Stage 13)
[0059] This stage of the rinsing procedure precedes the spinning phase. The drum rotation
speed is brought to the second RPM value of,
e.g., approximately 150 RPM, the recirculation pump
175 is maintained off; the discharge pump
160 is initially kept off. After some time, for example about 20 seconds, the discharge
pump
160 is activated. The drum continues to rotate at the second RPM value, then, after the
amount of discharged rinsing water is approximately 15 liters, and the level of rinsing
water in the tub
110 has fallen below the bottom of the drum
115 (thereby the contact of the laundry in the drum with the rinsing water is thus almost
null) the motor that makes the drum to rotate is stopped.
[0060] The Applicant has found that in this way the distribution of the laundry within the
drum
115 is more uniform: due to the presence of some rinsing water in the drum
115, the laundry does not get packed and distributes rather uniformly at the periphery
of the drum
115. This enhances the performance of the following spinning phase, since the laundry
is distributed inside the tub in a more symmetrical or uniform way.
- Fourteenth stage (Stage 14)
[0061] Finally, the spinning phase of the washing cycle is started. In this stage, the remaining
water in the tub is discharged. The drum rotation speed is increased relatively quickly
to a high RPM value, for example 450 RPM or more (depending for example on the washing
cycle selected by the user).
[0062] The present invention has been described by presenting an exemplary embodiment thereof,
which comprises several optional and non-essential features. Several modifications
to the described embodiments are possible and straightforward for those skilled in
the art, as well as other practical embodiments of the invention may be devised, without
departing from the scope of protection set forth in the following claims.
[0063] It is pointed out that the implementation, before a spinning phase, of a stage like
the thirteenth stage
Stage 13 described above - in which, starting with water in the tub at a level sufficient
for the laundry to be partly immersed, the drum is rotated at a speed that is sufficiently
high
(e.g., about 150 RPM) to cause (by centrifugal force) the laundry in the tub to more or
less stick around the periphery of the drum, and after some time the discharge pump
is activated to start discharging the water from the tub, while the drum is continued
to rotate until, after some time, an amount of water has been discharged that is sufficient
to cause the level of rinsing water in the tub to fall below the bottom of the drum,
thereby the drum rotation is stopped - is believed to be
per se advantageous, because it allows a better, more uniform distribution of the laundry
within the drum (thanks to the fact that while the drum is rotated there is still
water wetting the laundry), so that the latter is prevented from closely packing in,
possibly, just one location inside the drum.
1. A method of rinsing laundry in a laundry machine
(100) with a washing tub
(110) accommodating a rotatable laundry drum
(115), the method comprising the steps of:
- loading rinsing water into the tub;
- rotating the drum at a first rotation speed while recirculating the rinsing water
present in the tub and spraying the recirculated rinsing water into the drum;
- evacuating the rinsing water present in the tub,
characterized by comprising, before said step of evacuating the rinsing water:
- rotating the drum at a second rotation speed for a predetermined first time interval,
said second rotation speed being higher than the first rotation speed and sufficient
to cause the laundry being rinsed to stick against an inner surface of the drum due
to centrifugal force;
- stopping the drum rotation for a predetermined second time interval;
- after said second time interval, discharging from the tub a part of the rinsing
water present in the tub.
2. The method of claim 1, wherein during said steps of stopping the drum rotation and
discharging from the tub a part of the rinsing water present in the tub, the rinsing
water present in the tub is not recirculated.
3. The method of claim 1 or 2, wherein during said step of rotating the drum at a second
rotation speed, the rinsing water present in the tub is recirculated and sprayed into
the drum.
4. The method of any one of the preceding claims, wherein said second rotation speed
is of about 150 RPM.
5. The method of any one of the preceding claims, wherein said first rotation speed is
of about 50 RPM.
6. The method of claim 5, wherein during said step of rotating the drum at the first
rotation speed, the drum is rotated at least once at an intermediate rotation speed,
intermediate between the first and the second rotation speeds.
7. The method of claim 6, wherein said intermediate rotation speed is of about 75 RPM.
8. The method of any one of the preceding claims, wherein said step of rotating the drum
at the second rotation speed is additionally performed at least once without being
followed by said steps of stopping the drum rotation and discharging from the tub
a part of the rinsing water present in the tub.
9. The method of any one of the preceding claims, wherein before said step of evacuating
the rinsing water from the tub, the drum rotation speed is brought to said second
rotation speed.
10. The method of claim 9, wherein before said step of evacuating the rinsing water from
the tub, and after having brought the drum rotation speed to said second rotation
speed, the drum rotation speed is kept at the second rotation speed for a time before
starting to evacuate the rinsing water from the tub.
11. The method of claim 10, wherein the drum rotation is stopped after an amount of rinsing
water has been evacuated from the tub sufficient to cause a level of the remaining
rinsing water remaining in the tub to be below the bottom of the drum.
12. The method of claim 11, wherein after having evacuated the rinsing water from the
tub, a step of spinning the drum at a spinning speed higher than said second rotation
speed is performed.
13. The method of any one of the preceding claims, wherein said rotating the drum at the
first rotation speed comprises alternately rotating the drum clockwise and counter-clockwise.
14. A laundry washing cycle for a laundry machine, comprising a laundry rinsing phase
according to any one of the preceding claims.
15. A laundry machine comprising a tub (110) accommodating a rotatable drum (115), a discharge pump (160) activatable for evacuating at least partly liquid present in the tub, and a liquid
recirculation system (175,180,185) adapted to recirculated liquid present in the tub and spraying the recirculated liquid
into the drum, and a control unit (130) operable to control the operation of the machine, characterized in that the control unit is adapted to cause the machine perform a laundry rinsing method
according to any one of claims 1 to 13.