[0001] Present invention refers to a washing and drying machine, comprising a circuit for
air circulation, means for heating said air, means for conveying the heated air into
the laundry basket and a system for condensing the moisture extracted from the laundry.
[0002] Machines of the described type are normally in use to wash and dry household laundry.
[0003] They have a cabinet made out of enemelled metal sheet, allocating a washing tank,
which in turn holds a basket containing the laundry to be washed and dried. The basket
rotates during washing and drying phases round a hub, which is on the opposite side
of the glass window, used for loading the laundry into the basket and watching the
washing cycle.
[0004] At the end of the washing and spinning phases, the damp air is sucked out of the
basket by a centrifugal fan, heated and dried by means of electrical resistors, conveyed
again into the basket so as to act on the laundry, and so on.
[0005] Generally the air is conveyed into the basket through a suitable outlet, located
near the porthole; the sucked damp air is conveyed into a condensing chamber, where
it passes through a water rain so promoting the condensing of the moisture.
[0006] Also known are drying (non-washing) machines, wherein the air is conveyed into the
basket through the rear wall thereof, by means of holes suitably located round the
hub; it is important to point out that such non-washing driers shall not withstand
the spinning stress, therefore they need much lighter and thinner hubs.
[0007] Front loading washing and drying machines of the described type show inconveniences,
like the following:
- loading the laundry through the porthole is uncomfortable;
- the air conveyed into the basket gets partly lost through the gap between basket
and bellows and also because it is sucked before acting onto the laundry;
- heated air hits the glass of the porthole; the relevant heat gets therefore lost
as far as the laundry drying is concerned.
[0008] It is an object of the present invention to indicate a washing and drying machine,
which does not show the said inconveniences of the known machine.
[0009] To obtain the said object, the subject of present invention is a washing and drying
machine, comprising a circuit for air circulation, means for heating said air, means
for conveying the heated air into the laundry basket and a system for condensing the
moisture extracted from the laundry, characterized in that the machine provides for
a top loading system for the laundry.
[0010] In a preferred embodiment of the invention, the machine according to the invention
is characterized in that said means for conveying the heated air into the laundry
basket are so realized that the inlet of the air into the basket takes place through
a hub of the basket, which is axially hollow.
[0011] Other objects and advantages of the present invention will be clear from the detailed
desctiption which follows and from the attached drawings, which are supplied only
as an explanatory and not limiting example, wherein:
figure 1 shows a cross section of the part of the machine, expounding the system conveying
the heated air into the basket and the condensing chamber, according to the invention;
figure 2 shows a cross section, at right angle to the previous one, expounding the
condensing chamber of the machine according to the invention, wherein the horizontal
axis is rotated clockwise of 30°;
figure 3 shows a third cross section of the condensing chamber of the machine according
to the invention.
[0012] In figure 1, which shows a cross section of the part of the machine, expounding the
system conveying the heated air into the basket and the condensing chamber, according
to the invention, reference number 1 indicates the basket of the washing and drying
machine; said basket is fastened to bearing 20, which in turn is screwed to rear hub
18; front hub is not shown in the figure for the sake of compactness; as the washing
and drying machine provides for top loading the customary porthole on the front is
not present.
[0013] Damp air is sucked from basket 2 and passes, through a filter 17, into small chamber
3, which is a part of condensing chamber.
[0014] Small chamber 3 is divided from small chamber 5 by means of a baffle 4, which estends
for a good part of the condensing chamber (see fig. 3); baffle 4 forces the air to
a U shaped path to pass into small chamber 5, wherefrom it is sucked into small chamber
6, where there is located a centrifugal fan, not shown in the figure and driven by
the electric motor 8.
[0015] During the path between small chambers 3 and 5, damp air comes in contact with a
water shower, coming from outlet 21; water drops have the function to speed up the
condensation of the humidity which is present in small chambers 3 and 5; the condensed
moisture is collected in 19 (see fig. 2), wherefrom flows later in the machine tank.
[0016] From small chamber 6 the dried air is forced into a duct, made by two pieces 10 and
12; such a duct may also be made by only one piece as well as by many pieces, according
to specific manufacturing or economic problems. Inside said duct the air in contact
with electric heating resistors 13, which heat and dry it, and then arrives again
into basket 1 through the hollow rear hub 18; entering the basket the air passes trough
a filter 16, similar to filter 17.
[0017] The main fixed part 10 of the duct may be made of zamak die-casting or the like,
or out of metal sheet; besides resistors 13 are fastened to part 12; in this way also
duct 10 heats up so contributing to air heating and drying.
[0018] The lid 12 of the duct is also made out of metal sheet or by die-casting, e.g. an
aluminium alloy, and is fastened to fixed part 10 by means of small springs 11 and
14.
[0019] Filter 16, as well as filter 17, may be made out of metal sheet or plastic material,
while for the sake of inexpensiveness and ease of manufacturing they may be obtained
by means of 2 mm dia round holes or different shaped holes, made in such a number
that the free area represents about the 35% of the total area (measured as if it were
full).
[0020] In this way the air does not meet a great impediment for entering the basket; on
the other hand the coupling between duct and hub is airtight, thanks to suitable sealing
means, some of them being shown at 22, 23, 24, 25 and 26. In this way no flow reduction
is met and the necessary fan power, results being equal, is much lower than in the
known washing and drying machines.
[0021] It may be seen that air inlet in the basket, indicated by arrow 15, is perfectly
central; as a consequence the effect on the laundry of the heated and dried air is
optimized, in that the laundry, owing to basket motion, tends to open centrally shifting
towards basket walls, leaving free entry for the air and lending to very good uniformity
of drying.
[0022] As shown in fig. 1, the condensing chamber is for a great part made enblock with
the tank of the machine; lid 7 with motor 8 is attached by means of small springs,
one of them being shown at 9.
[0023] It may be seen that the fan, located inside chamber 6, being far from heating resistors
13, may be advantageously made out of plastic material, so greatly reducing manufacturing
costs.
[0024] On the other hand resistors 13 are nearer, in respect of known machines, to the entry
point of the heated air into the basket, so reducing the amount of heat which is lost
by dispersion; indeed the distance between the resistors and the entry point is, in
the machine according to the invention, less than 30 cm, in comparison of 60 cm in
the known machines.
[0025] In figure 2, which shows a cross section, at right angle to the previous one, expounding
the condensing chamber of the machine according to the invention, the elements bear
the same reference numbers as in fig. 1; reference number 19 indicates the moisture
collecting sump, taking in account that the horizontal axis here is rotated clockwise
of 30°.
[0026] Reference number 27 indicates the top opening of the tank, wherethrough the laundry
to be washed and dried is loaded.
[0027] In figure 3, which shows a third cross section of the condensing chamber of the machine
according to the invention, there is clearly shown the effect of the separating baffle
4 on the air path, indicated by arrow 28.
[0028] Condensing walls are obtained respectively from a piece of the tank, wall 29, and
an additional wall 30, preferably made out of rustless metal. Metal wall 30 has the
purpose of promoting the condensing process, on both sides, because it dissipates
the heat better.
[0029] The operation of the air drying and heating circuit in the described washing and
drying machine comes out clearly from the given description and from the attached
drawings.
[0030] Also clear are the characteristics of the described machine.
[0031] Clear too are the advantages of the washing and drying machine according to the invention.
Particularly they are represented by:
- practically air tight circuit between the fan and the basket;
- reduced heat dispersion; better heating efficiency for laundry drying;
- absolutely central air inlet into basket, hence greater uniformity of effect on
the laundry;
- easier and more comfortable loading of the laundry;
- condensing effect on the gap area of the metal wall.
[0032] It is clear that many variations to the machine described as an example are possible
to the skilled in the art, without departing from the novelty principles inherent
to the invention.
[0033] Among the possible variations there is the possibility to realize the damp air condensation
through the contact between said air and a cold wall. In this sense the variation
can be obtained realizing the wall 30 with an inner space wherein cold water is circulated.
In this way the temperature of wall 30 is kept constantly cold so promoting the condensation
and avoiding the water shower from outlet 21.
1. Washing and drying machine, comprising a circuit for air circulation, means for
heating said air, means for conveying the heated air into the laundry basket and a
system for condensing the moisture extracted from the laundry, characterized in that
the machine provides for a top loading system for the laundry.
2. Washing and drying machine, comprising a circuit for air circulation, means for
heating said air, means for conveying the heated air into the laundry basket and a
system for condensing the moisture extracted from the laundry, characterized in that
said means for conveying the heated air into the laundry basket show airtight sealing
characteristics so that the air circuit, from the sucking point to the basket entry
is pratically airtight.
3. Washing and drying machine, comprising a circuit for air circulation, means for
heating said air, means for conveying the heated air into the laundry basket and a
system for condensing the moisture extracted from the laundry, characterized in that
said means for conveying the heated air into the laundry basket are realized in such
a way that the air entry into the basket takes place through a hub (18) of the basket,
which is axially hollow.
4. Washing and drying machine, comprising a circuit for air circulation, means for
heating said air, means for conveying the heated air into the laundry basket and a
system for condensing the moisture extracted from the laundry, characterized in that
said system for condensing the moisture extracted from the laundry comprise a condensing
chamber (3,4,5), at least a part of which is obtained enbloc with the washing tank
(29) and has an additional wall (30) preferably made out of rustless metal.
5. Washing and drying machine, according to claim 3, characterized in that said means
for conveying the heated air into the laundry basket comprise a duct (10, 12) connecting
the small chamber (6) of the air circulating fan with the basket hub (18).
6. Washing and drying machine, according to claim 5, characterized in that said air
circulating fan is preferably of the centrifugal type.
7. Washing and drying machine, according to claim 5, characterized in that said duct
comprises a main part (10) made out of metal sheet or by die-casting, and a lid (12)
attached to the main part, and airtight means (25) between said main part and said
lid.
8. Washing and drying machine, according to claim 5, characterized in that said duct
(10,12) is attached to said basket hub (18) by airtight means (22, 23, 24, 26).
9. Washing and drying machine, according to claim 3, characterized in that between
said hollow hub (18) and the inside of the basket there is provided a filter (16)
made out of a metal sheet or by casting a plastic material, with a plurality of holes
having a suitable shape.
10. Washing and drying machine, according to claim 9, characterized in that the empty/full
ratio of this filter is greater than 0.3.
11. Washing and drying machine, according to claim 5, characterized in that said duct
(10,12) comprises internally said heating means (13) for heating and drying the air.
12. Washing and drying machine, according to claim 11, characterized in that said
heating means (13) are fastened at least to one of the internal walls (10,12) of the
duct.
13. Washing and drying machine, according to claim 11, characterized in that said
heating means comprise electric resistors (13).
14. Washing and drying machine, according to claim 11, characterized in that said
heating means (13) are located at a distance from the air entry point (15) into the
basket which is less than 40 cm.
15. Washing and drying machine, according to claim 4, characterized in that said condensing
chamber (3,4,5) comprises a separating baffle (4) which forces the air to increase
its path inside the chamber.
16. Washing and drying machine, according to claim 4, characterized in that said condensing
chamber (3,4,5) is associated to an air circulating fan.
17. Washing and drying machine, according to claim 16, characterized in that the air
circulating fan is made out of plastic material.
18. Washing and drying machine, according to claim 4, characterized in that inside
said condensing chamber (3,4,5) there is an outlet (21) hitting the damp air with
a water shower, so speeding up the humidity condensation.
19. Washing and drying machine, according to claim 4, characterized in that said additional
wall (30) of the condensing chamber (3,4,5) provides for a double wall with an internal
space for the circulation of a refrigerating liquid, particularly water, in order
to realize the condensation of the damp air.