[0001] The present invention concerns a method of washing for washing machine.
[0002] The washing machines constructors engage constant research to move that, their machines
offer the best performances with allowing savings to be made in running cost, with
reduction in consumption of energy, water and detergents. For example,
US patent n° 3.388.410 describes a washing method which provides during the whole washing time, as also
during the rinsing time, an alternation of cycles in which the drum containing the
clothes to be washed, is made to rotate at high speed, with cycles during which the
drum is made to rotate at a lower speed. The high speed being sufficient to make the
centrifugal force acting on the clothes overcome the force of gravity and maintain
the ones against the drum wall, while during the cycles in which the drum is made
to rotate a lower speed, the clothes fall back into the drum base itself. The soapy
washing solution or the rinsing water is taken from the base of the washing tub and
is continuously fed again by spraying, by means of recirculation pump, into the drum.
During drum rotation at the higher speed, there is the formation of a ring of solution
or of rinsing water wherein the clothes are constantly immersed. The washing and rinsing
at high speed with clothes adhering to the wall drum and sprayed by the soapy solution
or recycled rinsing water improve the efficiency of washing and rinsing phases. Moreover
that recirculation allows liquid quantity used to be reduced to a certain extent.
[0003] EP 0.726.349 describes a method of washing machine comprises at least one washing phase which
includes a cycle of work at high speed and recirculation of water during which a drum
containing the laundry to be washed and rotatory housed in a washing tub, is made
to rotate at a first speed, sufficiently high to generate a centrifugal force which
causes arrangement of the laundry along the periphery of the drum and, simultaneously,
the water in the washing tub is taken from said tub and is returned therein by spraying
at a central part of the drum. A subsequent work cycle at low speed then takes place,
during which the drum is made to rotate at a second speed, lower than said first speed
and such as to allow remixing of the laundry, while the recirculation of water is
substantially interrupted. The cycle of work at high speed and recirculation of water
has a duration limited to the time necessary for the complete removal of detergent
from a detergent container and during its performance part of the water taken from
the tub is made to pass through the container of detergent and subsequently reintroduced
into the tub.
[0004] In the two cases, the quantity of water fed into the washing tub must be sufficient
to ensure that, during the recirculation, a quantity of water remains always in the
tub so as to prevent the cavitation of the recirculation pump. This is more likely
to occur during the cycles of drum rotation at low speed.
[0005] In
US patent 3 388 410, this problem is solved in making the tub very deep, and in feeding therein an abundant
quantity of water because during the years to which this patient dates back the problem
of water and energy consumption was not less felt than the actual epoch.
The problem subsists actually in case of relation drum volume clothes quantity, small.
[0006] In view of the state of the art described above, the object of the present invention,
as characterised in the claims, is to permit a good clothes distribution in the drum
and performances improvement for washing in particularly in case of relation drum
volume, clothes quantity small ; in order to adapt the drum volume for the same machine
nominal garment to reduce consequently the energy and the water consumption to optimize
the power of the washing machine motor.
[0007] These and others features of the present invention will be made clearer from the
detailed description of some of its embodiments, illustrated by way of a non limiting
example in accompanying with the drawings on which :
- figure 1 shows a diagram on which all the phases of the washing are represented, including
rinsing and drying phases ,
- figure 2 shows an enlargement of the part of the diagram corresponding only at the
washing phase.
[0008] Regarding fig 1, we can see on the diagram showing water level
1 and drum speed
2 that after a first wash period of about 57 minutes, the drum is subject to two brief
impulses
11,12 in order to obtain laundry detachment. The phase impulses
11,12 being followed by a washing phase
10 strictly speaking of about one hour duration until the rinsing phase.
[0009] Regarding fig. 2, we see on this diagram that the impulses
11,12 for better laundry speed detachment correspond to brief drum increasing of about
220 to 300 RPM separate by a short pause
13 and followed by a longer pause
14, before the standard washing phase continuation
17. We can remark that these impulses
11,12 are accompanied with water higher level
15,16 with picks corresponding to the drum speed impulses
11,12.
[0010] It results of this application method that the using of small impulses
11,12 of speed motor highest during the clothes washing phase permits a drum acceleration
able to redistribute the clothes inside the drum, particularly in the case of the
relation "drum volume / clothes quantity" low. These impulses being activated automatically,
only in the case of nominal loading of the machine, in view to make optimal the drum
volume and to reduce the required energy, the water consumption and motor power ;
the loading being determined by the washing machine itself. The using of the process
staying however possible in the case of volume drum more important to accelerate the
clothes distribution in the drum.
1. Method of washing for washing machine comprising a washing which includes a cycle
at higher speed during which a drum containing the laundry to be washed rotatory housed
in a washing tub fed with clean water is made to rotate at a first speed, sufficiently
high to generate a centrifugal force which form and maintain annular layer of clothes
against the drum peripheral wall with cleaning solution and a subsequent work cycle
during which the drum is made to rotate at a second speed lower than said first speed
and such as to allow remixing of the laundry while the recirculation of the water
is substantially interrupted characterized in that the said work cycle at higher speed is realized in the form of brief impulses (11,12) separate each other by a short drum stopping sequence (13) and in that this work said at higher speed is continued by a last drum stopping sequence (14) longer than those separating the impulses (11,12) and that this last drum stopping sequence (14) is accompanied with the maintain of the water at higher level (16).
2. Method according to claim 1 characterized in that, the work cycle at higher speed is automatically put in order, only when certain
conditions are united.
3. Method according to claim 2 characterized in that, the work cycle at higher speed is put in order, when the drum loading is nominal.
4. Method according to claim 1 characterized in that, the work cycle at higher speed can be put in order, by the user of the machine.
5. Method according to claim 1 characterized in that, the work cycle at higher speed is effected at about 220 to 300 RPM depending to
the washing machine type.
6. Method according to claim 1, characterized in that, the work cycle at higher speed comprises two impulses (11,12) or more.
7. Method according to claim 1 or 6, characterized in that, the impulses (11,12) could be repeated at any time during the washing phase.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description