[0001] The present invention relates to washing machines or dishwashers provided with a
flood-preventing device, and in particular to such a machine provided with a member
which allows to check the working of said device.
[0002] It is known that washing machines or dishwashers for domestic use are generally provided
with a flood-preventing device whose function is to stop the entrance of water coming
from the hydraulic network in case of leakage from any component of the machine. This
device substantially consists of a tray located at the bottom of the machine, where
the possible leak is collected, and a float placed in the tray which activates a microswitch
when raised.
[0003] The activation of the microswitch causes the closure of the water inlet valve and
usually also the activation of the drain pump, so as to prevent the risk of flooding.
[0004] Given the importance of this safety device, it is clear how useful it is to be able
to check the correct working thereof already in the manufacturing and test phases.
However, the position of the float on the bottom of the machine makes its manual activation
very difficult after the tray has been mounted.
[0005] Moreover, there is the risk that the float is damaged or moved during the mounting
of the tray, whereby it can become unworkable after a possible previous check.
[0006] The only type of check presently available consists of pouring water into the tray
to simulate a leakage. It is clear that such a procedure is unpractical and time-consuming,
since the water must then be removed and drained out. Therefore this type of check
is not carried out systematically on the production line but only on some sampled
specimens.
[0007] Therefore the object of the present invention is to provide a washing machine or
dishwasher suitable to overcome the above-mentioned drawbacks.
[0008] This object is achieved by means of a machine having the characteristics disclosed
in claim 1.
[0009] Reference will be made hereafter specifically to a dishwasher, while being clear
that what is said can be applied also to a washing machine or any other kind of similar
machine.
[0010] The main advantage of the machine according to the present invention is to allow
a simple and safe way for a systematic check of the working of the flood-preventing
device. This obviously results in a dramatic increase in the reliability of said device.
[0011] A further advantage of the present machine is that it does not require significant
changes in order to achieve said function, whereby the costs and production processes
remain substantially unchanged.
[0012] These and other advantages and characteristics of the machine according to the present
invention will be clear to those skilled in the art from the following detailed description
of an embodiment thereof, with reference to the annexed drawings wherein:
Fig. 1 is a diagrammatic sectional view of the lower portion of a dishwasher according to
the invention; and
Fig.2 is a partial enlarged view of fig. 1 which shows in detail the member for the check
of the flood-preventing device.
[0013] With reference to said figures, there is seen that a dishwasher conventionally includes
a bottom tray 1 wherein, at an almost central position, there is placed a float 2.
The tray I can collect a possible water leak from any component of the machine, such
as the pump 3, the duct which feeds the sprinkler 4, the chamber 5 at the bottom of
the tank, etc.
[0014] The microswitch 6 is mounted above the float 2 so as to be activated as soon as the
water collected in the tray 1 causes a little raising of the latter (dotted line in
fig.2).
[0015] The novel aspect of the machine according to the present invention is a deformable
diaphragm-shaped member 7 which water-tightly closes a hole formed in the tray 1,
preferably at the center of the float 2. The presence of this hole allows to check
the working of the flood-preventing device by simply mechanically pushing upwards
the float 2 through deformation of the diaphragm 7. This type of check can easily
be made automatic and carried out directly on the production line in a systematic
manner, that is on 100% of the machines.
[0016] The member 7 in particular is provided with a peripheral crown 7a having a seat for
the fitting thereof on the thickness of the tray 1, as well as a central peg 7b projecting
upwards close to the float 2 so as to minimize the deformation required for the check.
[0017] It would also be possible, though less practical, to form the hole not at the float
2 but at a relay mechanism which receives the push upwards from the diaphragm 7 and
transmits it to the float 2.
[0018] It is therefore clear that the above-described and illustrated embodiment of the
device according to the invention is just an example susceptible of various modifications.
In particular, the shape and position of the hole and of the relevant closing deformable
member 7 may be freely changed according to the needs, as long as the float 2 can
be raised by pushing upwards on said member 7.
1. Washing machine, dishwasher or the like, including a bottom tray (1) suitable to collect
the water leaking from any component of the machine, a float (2) in said tray (1),
and a microswitch (6) which can be activated by said float (2) as soon as the water
collected in the tray (1) causes the raising of the float (2), characterized in that
the tray (1) has a hole which is water-tightly closed by a deformable diaphragm-shaped
member (7), the float (2) being raised directly or indirectly by pushing upwards on
said deformable diaphragm-shaped member (7).
2. A machine according to claim 1, characterized in that the hole in the tray (1) is
formed at the float (2).
3. A machine according to claim 1, characterized in that the hole in the tray (1) is
formed at a relay mechanism which receives the push upwards from the diaphragm (7)
and transmits it to the float (2).
4. A machine according to claim 1 or 2, characterized in that the diaphragm (7) is provided
with a peripheral crown (7a) having a seat for the fitting thereof on the thickness
of the tray (1), and a central peg (7b) projecting upwards.