[0001] The present invention refers to a top-loading clothes washing machine of the kind
provided with an improved top closing lid.
[0002] While reference is made in the following description to a top-loading clothes washing
machine of a single-duty type, i.e. designed to only wash and spin-dry clothes, it
will be readily appreciated that what is disclosed and explained in connection therewith
may equally be applied to, and is therefore suitable for, a combined clothes washing
and drying machine, i.e. a so-called washer-drier, as far as it is of the top-loading
kind.
[0003] Top-loading clothes washing machines are generally known in the art to be provided
with a top or upper lid of an essentially traditional kind, in which said lid is usually
made in a sandwich-like manner with a top surface generally made of sheet-steel extending
on a horizontal plane, and a corresponding lower surface, or counter-lid, made of
plastics and facing towards the interior of the machine, i.e. towards the upper opening
of the drum-holding tub.
[0004] Between this opening and said counter-lid there is provided a funnel-shaped member,
forming practically a hopper, which is substantially intended to act as both a guiding
member and a safety means.
[0005] As a guiding member, such a hopper-like member is designed to prevent the clothes
being loaded in the drum from inadvertently slipping outside the upper loading aperture,
while being guided to obligatorily fall through said loading aperture into the drum;
in fact, along the upper portion thereof said hopper, along the upper portion thereof,
is joined in a continuous manner with the upper edge of the outer casing of the washing
machine, so that it is practically impossible for clothes to be placed on the machine,
upon of course the lid thereof having been raised, without these clothes being spontaneously
directed into the drum.
[0006] As a safety provision, such a hopper prevents a user from being able to gain access
into the interior of the machine from above, thereby avoiding easily imaginable risks
and dangerous situations.
[0007] However, the sole provision of such counter-lid usually gives rise to a drawback
in that the steam generated inside the washing tub of the machine tends to seep through
the passages it finds along the upper shutting lid of the tub and leaks into the surrounding
ambient by passing through the interstice formed between the counter-lid and the upper
portion of the hopper, or through the member joining the upper edge of the hopper
with the upper edge of the outer casing of the machine.
[0008] In view of doing away with such drawback, a known prior-art solution lies in providing
the lower surface of the counter-lid with an appropriate elastic sealing gasket, which
is generally made as a closed-loop annular member and is arranged so that, when the
lid is closed, it fully surrounds the upper aperture of the hopper and, as a result,
closes and seals any passage that may exist between such aperture of the hopper and
the peripheral or outermost zone of said counter-lid, as this is symbolically shown
in Figure 1, which is a perspective view of the lower surface of an upwards facing
counter-lid, and in Figure 2, which is a schematical, cross-sectional view of a portion
of the counter-lid illustrated in Figure 1 as viewed along the A-A sectional plane.
[0009] Such solution is certainly effective and capable of being produced on an industrial
scale. However, it proves rather demanding from a manufacturing point of view, since
it requires a number of distinct manufacturing steps to be performed in order to:
- make such gasket member by extrusion,
- cut, prepare and properly shape said gasket member,
- apply an appropriate adhesive layer on the same gasket member,
- install the thus prepared gasket member on a proper groove provided in the lower surface
of said counter-lid.
[0010] When added together, all these manufacturing steps generate an aggregate cost that,
owing to both the number of the steps to be performed individually and the time required
to complete all of them, turns out as being practically unacceptable in connection
with such highly competitive and highly automated industrial manufacturing process
as the one involved in the production of washing machines in general.
[0011] It would therefore be desirable, and it is actually a main object of the present
invention, to provide a top-loading clothes washing machine, in which the manufacturing
steps required to provide the lower gasket member of the counter-lid can be carried
out and completed with simple, low-cost manufacturing operations allowing for a great
extent of automation, without having to accept any drawback or disadvantage of a functional
kind.
[0012] According to the present invention, these aims as set forth above, along with further
ones that will become apparent from the following description, are reached in a top-loading
clothes washing machine made so as to incorporate the features and characteristics
as recited in the appended claims. Features and advantages of the present invention
will anyway be more readily understood from the description that is given below by
way of non-limiting example with reference to the accompanying drawings, in which:
- Figure 3 is a symbolical perspective top view of the upper portion of a top-loading
clothes washing machine with its lid in a partially open state;
- Figure 3A is a perspective view of the lower surface of the lid illustrated in Figure
3, as shown in the state in which it faces upwards;
- Figure 4 is a cross-sectional view along the sectional plane Z-Z of Figure 3A of a
portion of a counter-lid according to the present invention;
- Figure 5 is a cross-sectional view similar to the one appearing in Figure 4 of a further
improved embodiment of a counter-lid according to the present invention;
- Figures 6 and 7 are cross-sectional views of two further improved embodiments of a
counter-lid according to the present invention, respectively;
- Figure 8 is a symbolical view similar of a further improved embodiment of a gasket
member of a counter-lid according to the present invention;
- Figure 9 is a view corresponding to the one appearing in Figure 3 of a different embodiment
of a top-loading clothes washing machine, as shown with its lid in a partially open
state.
[0013] With reference to Figures 3 and 3A, in a top-loading clothes washing machine according
to the present invention there are provided a washing tub 1 in which there is rotatably
supported the inner drum holding the clothes to be washed, an upper lid 2 enabling
access to the interior of the inner drum to be gained from above, an outer casing
3, a hopper 4 which is located above the upper aperture of the tub 1 and joins with
its upper portion with the outer upper edge 5 of the outer casing 3, an upper lid
6 provided with a lower counter-lid 7.
[0014] With reference to Figure 4, in the lower surface 8 of said counter-lid 7 there is
provided a groove 9 extending in a closed-loop pattern therearound to substantially
surround the loading aperture of said hopper 4when the lid 6 is closed.
[0015] Using the by now largely known overinjection technique, in this groove 9 there is
formed a gasket 10 of a suitable thermoplastic, elastic material, wherein said gasket
does not only fill up said groove, but also protrudes outwardly therefrom all along
the extension thereof; therefore, when the lid is lowered into closing, said gasket
protrudes downwards, so that the resulting outward protrusion 11 comes to arrange
itself in the form of a closed-loop ring elastically separating said counter-lid,
and the related lid, from said hopper. In addition, the resulting separation is a
continuous one extending evenly all along the closed loop formed by the groove 9 with
a constant cross-section. This feature also enables a steam-tight sealing effect to
be obtained between the inside of the hopper and the outer ambient, when the lid is
closed, since the lid carrying said sealing gasket means is in this manner capable
of actually working as a "stopper" plugging said hopper.
[0016] It can therefore be readily appreciated that the above-mentioned overinjection technique
is fully effective in enabling the main purpose of the present invention, aimed substantially
at cutting down the costs of providing said gasket as set forth earlier in this description,
to be reached in an ideal manner. It can in fact be most readily appreciated that
a single overinjection moulding operation is all that it takes to form a complete
and definitively applied gasket on the counter-lid, without any additional operation
being required or any interruption in the manufacturing cycle being introduced.
[0017] Furthermore, the above-mentioned overinjection moulding operation can be further
optimised through a moulding sequence in which there is first moulded, eg. injection
moulded, the counter-lid and said gasket is then overinjected onto the thus formed
counter-lid immediately thereafter, i.e. before allowing the counter-lid to cool down
excessively. This in fact enables a general improvement to be obtained as far as both
the cost-effectiveness of the entire manufacturing step and the ultimate qualitative
result are concerned, considering that if a base support to be overinjected is first
heated up, the clinging, i.e. the adherence of the overinjected material to such base
is much more effective.
[0018] The above-described invention allows for a number of advantageous improvements to
be implemented. So, for instance, a first improvement lies in the possibility for
the portion of said annular gasket 11 protruding from said groove to be subdivided
into two distinct lips 11A and 11B, as this is shown schematically in Figure 6, where
it can be noticed that these two lips are oriented inwards and outwards, respectively,
relative to the gasket itself, so that, further to improving the elastic dampening
effect, they prevent air or foreign bodies from passing therethrough in either direction.
[0019] A second improvement lies in the possibility for said gasket to be made by providing
it with a thickness that increases gradually starting from the position thereof near
the hinges, i.e. the rear position of said gasket, and moving towards the opposite,
i.e. front position thereof. Figures 6 and 7 show respective cross-sectional views
of the gasket with its respective lips 11A and 11B, in which Figure 6 illustrates
the cross-section profile of the gasket in correspondence of the side "11A", whereas
Figure 7 illustrates the cross-section profile of the gasket in correspondence of
the side "11B". It should be noticed how, in the first case (Figure 6), said gasket
has a height m that is lower than the height M of the same gasket on the side shown
in Figure 7.
[0020] Such solution is generally preferred and used since loads, stresses and shocks imposed
from above, and even the closing speed and, as a result, the speed at which the gasket
on the counter-lid strikes against the hopper surface, are generally greater in the
front zone of the lid.
[0021] It should be briefly noted here that such differentiated sizes of the gasket are
certainly not so easy to obtain with the prior-art technique of extrusion, in which
the gasket id first extruded and then cut to length and attached to the counter-lid.
[0022] A further improvement is obtained by providing a material interruption or gap 12
in the profile of the portion of gasket protruding from the groove 9, as this is symbolically
illustrated in Figure 8. This gap allows gas to pass therethrough from said hopper
to the outside ambient when said lid is closed.
[0023] In a preferred manner, the above-mentioned gap is situated in the rear portion of
the gasket, i.e. on the side of the gasket that is opposite to the one facing the
user. Such improvement enables a venting provision to be created for letting out air
and steam forming inside the washing tub and generally seeping out from the lid of
the machine, which must be exhausted outside without other internal parts of the machine
being affected by it. In addition, by selecting the portion of the gasket on the rear
side of the lid to locate such gap, the resulting vent will not let out steam directly
into the space where the user generally stands.
[0024] It has been furthermore found experimentally that, among the most favourable conditions
in view of overinjecting said gasket onto the counter-lid, the optimum ones are attained
when the material which the counter-lid 7 is made of is polypropylene, in particular
of the type known on the market under the trade name of "CARBORAN", as well as when
the material used to overinject the gasket 10 is a thermoplastic material containing
propylene, rubber, additives, oil, etc.
[0025] With reference to Figure 9, it should further be noticed that, in certain embodiments,
the hopper 4 does not join directly with the upper portion of the outer casing, but
rather extends upwards until it joins up with a joining member 14 that seals and joins
horizontally the upper edge of said hopper with the outer upper edge 5 of said outer
casing 3. It will in this case be appreciated that this gasket 10, along with all
above-described improvements and embodiments thereof, refers to a similar or equivalent
type of gasket, which however extends between said counter-lid and said joining member
14.
1. Top-loading clothes washing machine, or combined clothes washing a drying machine,
comprising:
- a tub (1) for holding and washing the clothes,
- a drum housed and rotatably supported in said tub, and an upper lid (2) enabling
access to be gained into the interior of said drum,
- an outer casing (3),
- a hopper (4) situated in correspondence to said upper lid (2) and possibly provided
with a joining member (14) that seals the upper edge of said hopper against the upper
edge (5) of said outer casing (1),
- an upper lid (6) provided with a counter-lid (7) on the lower side thereof,
- elastic gasket means provided between said counter-lid (7) and an upper portion
of said hopper (4), or between said counter-lid and said joining member (14),
- a groove (9) extending along the inner surface of said counter-lid and adapted to
receive said elastic gasket means, characterized in that said elastic gasket means are formed by a ring of a suitable thermoplastic material
over-injected into said groove (9) extending in the lower surface of said counter-lid
(7), and in proximity of the outer edges thereof.
2. Top-loading clothes washing machine according to claim 1, characterized in that the portion (11) of said loop-like gasket (10) that protrudes from said groove (9)
comprises two distinct lips (11A, 11B), one of which (11A) is oriented inwards and
the other one (11B) is oriented outwards with respect to said gasket (10).
3. Top-loading clothes washing machine according to claim 1 or 2, characterized in that the thickness of the outer portion of said gasket (10) is not constant, and that
said thickness is larger (M) in that portion of periphery (b) of said gasket which lies farther away from the hinge of
said upper lid (6), whereas it is smaller (m) in that portion of periphery (a) of said gasket which lies closer to said hinge.
4. Top-loading clothes washing machine according to any of the preceding claims, characterized in that a material interruption or gap (12) is provided in said loop-like gasket (10) so
as to allow gas to escape therethrough from said hopper into the outside ambient when
said lid is closed.
5. Top-loading clothes washing machine according to claim 4, characterized in that said material interruption or gap (12) is provided in the rear side of said gasket
(10).
6. Top-loading clothes washing machine according to any of the preceding claims, characterized in that said counter-lid (7) is made of polypropylene, and that said thermoplastic material
of said gasket (10) contains propylene, rubber, additives, oil.
Amended claims in accordance with Rule 86(2) EPC.
1. Top-loading clothes washing machine, or combined clothes washing a drying machine,
comprising:
- a tub (1) for holding and washing the clothes,
- a drum housed and rotatably supported in said tub, and an upper lid (2) enabling
access to be gained into the interior of said drum,
- an outer casing (3),
- a hopper (4) situated in correspondence to said upper lid (2),
- a further upper lid (6) provided with a counter-lid (7) on the lower side thereof,
- elastic gasket means provided between said counter-lid (7) and an upper portion
of said hopper (4),
- a groove (9) extending along the inner surface of said counter-lid and adapted to
receive said elastic gasket means, which are formed by a ring of a suitable thermoplastic
material over-injected into said groove (9) extending in the lower surface of said
counter-lid (7), and in proximity of the outer edges thereof, characterized in that a portion (11) of said loop-like gasket (10) protrudes outwardly from said groove
(9) comprises two distinct lips (11A, 11B), one of which (11A) is oriented inwards
towards the central vertical axis of the machine and the other one (11B) is oriented
outwards away from the central axis of the machine with respect to said gasket (10).
2. Top-loading clothes washing machine according to claim 1, characterized in that the thickness of the outer portion of said gasket (10) is not constant, and that
said thickness is larger (M) in that portion of periphery (b) of said gasket which lies farther away from the hinge of
said upper lid (6), whereas it is smaller (m) in that portion of periphery (a) of said gasket which lies closer to said hinge.
3. Top-loading clothes washing machine according to any of the preceding claims, characterized in that a material interruption or gap (12) is provided in said loop-like gasket (10) so
as to allow gas to escape therethrough from said hopper into the outside ambient when
said lid is closed.
4. Top-loading clothes washing machine according to claim 3, characterized in that said material interruption or gap (12) is provided in the rear side of said gasket
(10).
5. Top-loading clothes washing machine according to any of the preceding claims, characterized in that said counter-lid (7) is made of polypropylene, and that said thermoplastic material
of said gasket (10) contains propylene, rubber, additives, oil.