FIELD OF THE INVENTION
[0001] The present invention concerns a method and the relative device to indicate the need
for reintegration, or topping up, of a regenerating substance of the anti-calcium
function, such as for example sodium chloride, or more simply salt, in a washer machine
such as a dishwasher, glass-washer or suchlike.
[0002] The invention allows to obtain this function in a simple, reliable, economical and
efficient manner.
BACKGROUND OF THE INVENTION
[0003] It is known that in washer machines, such as for example dishwashers, glass-washers
or suchlike, of the domestic or industrial type, an anti-calcium unit is provided,
the function of which is to decalcify the running water, fed from the mains water
supply and used in the washing cycles, reducing the deposit of calcium on the various
components of the dishwashers, improving the washing functionality, limiting malfunctions
and increasing duration thereof.
[0004] Such anti-calcium units normally comprise a tank filled with water, into which a
determinate quantity of salt is poured in order to create a saline solution with a
desired level of saturation.
[0005] In a position adjacent to the salt tank, a tank is provided containing ion exchange
resins which, as the washing water to be decalcified passes, exchange ions, typically
sodium, with the ions of calcium and magnesium present in the water, substantially
eliminating the calcium therefrom.
[0006] It is also known, after a certain number of washing cycles, to automatically effect
a cycle to regenerate the resins, during which a certain quantity of clean water,
taken from a suitable tank, is made to circulate, firstly through the saline solution
and then through the tank of resins. The circulation of clean water on the one hand
causes the resins to be charged with sodium ions, and consequently to be regenerated,
and on the other hand it causes the saline solution to become diluted. The quantity
of saline solution used to regenerate the resins frees a quantity of calcium and magnesium
ions, and this excess of calcium and magnesium is discharged through the discharge
pan of the washer machine.
[0007] As the various cycles of regeneration proceed, there is a progressive reduction in
the salt in the saline solution provided inside the tank, so as to make reintegration
necessary.
[0008] In the state of the art, various systems have been proposed in order to indicate
to the user that the salt needs reintegration.
[0009] One of the most widespread solutions provides to use a float, associated with a magnet,
disposed inside the salt tank, which, according to the progressively decreasing level
of saturation of the saline solution, is gradually displaced downwards, until it reaches
a position wherein it indicates a lack of salt.
[0010] It is also known to provide sensors (for example, reed switches), associated with
the float, in order to detect that the position corresponding to a lack of salt has
been reached, and to send a signal to the command unit of the machine in order to
signal to the user that reintegration is necessary.
[0011] This known solution has very high cost, which can reach up to 20-25% of the total
cost of the anti-calcium unit, and is easily subject to malfunctions due to the possible
defectiveness both of the float system and also of the sensor.
[0012] The float, for example, can be subject to blockages inside the tank, either in a
position where it erroneously signals the absence of salt, or in a position where
it erroneously signals the presence of salt, in both case creating anomalies and malfunctions.
[0013] The sensor too can be subject to defects which, in not detected in time, can entail
a prolonged use of the dishwasher under incorrect conditions.
[0014] One purpose of the present invention is therefore to perfect a method, and achieve
the relative device, to quickly indicate the need for reintegration of the regenerating
substance of the anti-calcium function in a washer machine , which is efficient, reliable
and that does not entail high costs of production and functioning due to the fact
that it does not require either floats or sensors or systems of any other type, associated
with the tank that contains the regenerating substance.
[0015] The Applicant has devised, tested and embodied the present invention to overcome
the shortcomings of the state of the art and to obtain these and other purposes and
advantages.
SUMMARY OF THE INVENTION
[0016] The present invention is set forth and characterized essentially in the main claims,
while the dependent claims describe other innovative characteristics of the invention.
[0017] The invention is applied in a washer machine comprising, in conventional manner,
a tank containing the regenerating substance, hereafter called simply salt, associated
with a tank for the ion exchange resins, a tank for the regeneration water and a command
unit suitable to activate, after a defined number of washing cycles, a cycle to regenerate
the resins. The regeneration cycle provides to make clean water flow through the salt
tank and the resin tank, and to discharge the water loaded with the calcium and magnesium
salts.
[0018] The method according to the invention is based on the premise that the quantity of
salt removed from the tank (that is, the dilution of the saline solution) in every
regeneration cycle is substantially constant.
[0019] The method provides a first step in which, at the moment of a reintegration operation,
the quantity of salt poured by the user into the appropriate tank is measured, as
will be explained hereafter.
[0020] The method then provides a second step in which, for every regeneration cycle, from
the quantity of salt measured at the beginning, a quantity is deducted corresponding
to the quantity presumed to have been removed with the regeneration.
[0021] With the succeeding regeneration cycles, calculating the difference, the command
unit is able to establish after how many regeneration cycles the quantity of salt
initially introduced has been reduced to a pre-established residual value in which
the need for reintegration is indicated.
[0022] To measure the quantity of salt introduced with the reintegration, the method according
to the invention provides to use a pressure sensor associated with the discharge pan.
The pressure sensor effects the measurement by detecting the quantity of water that
flows into the discharge pan following the unloading of salt into the appropriate
tank.
[0023] In one embodiment of the invention, the pressure sensor is a normal pressure switch.
[0024] According to an advantageous variant, the pressure sensor is of the linear type.
[0025] The use of a linear pressure sensor allows to discriminate when the flow of water
into the discharge pan is caused by the pouring of a corresponding quantity of salt
into the relative tank, and not by other causes, for example the emptying of a saucepan
or a glass.
[0026] The pressure sensor, which can already be advantageously present in the discharge
pan in order to carry out other functions connected to the functioning of the washer
machine, is in fact able to discriminate the discharge dynamics of the water, thus
detecting the moment when the salt is reintegrated.
[0027] This detection is interpreted by the command unit as a so-called zero time, from
which the counting is started of the regeneration cycles, which determine, according
to the initial quantity measured by the same pressure sensor, and according to the
presumed quantity removed with every regeneration cycle, the progressive reduction
in the quantity of salt until the pre-established condition is reached, wherein the
need for reintegration is indicated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] These and other characteristics of the present invention will become apparent from
the following description of some preferential forms of embodiment, given as a non-restrictive
example with reference to the attached drawings wherein:
- fig. 1 is a schematic view of a washer machine in which the present invention is applied;
- fig. 2 is a schematic view of a first form of embodiment of the device according to
the present invention;
- fig. 3 shows a variant of fig. 1.
DESCRIPTION OF SOME PREFERENTIAL FORMS OF EMBODIMENT OF THE INVENTION
[0029] With reference to the attached figures, the reference number 10 denotes in its entirety
a device to indicate the need for reintegration of an anti-calcium substance, in this
case salt, in a washer machine, in this case a domestic dishwasher 16.
[0030] The device 10 comprises a tank for the salt 17, a tank 19 containing ion exchange
resins, disposed downstream of the salt tank 17, a discharge pan 20 for the water
and a tank for the regeneration water 21, disposed upstream of the salt tank 17.
[0031] A linear pressure detection device is associated with the pan 20, and comprises in
this case an air trap 28 with which a pressure sensor 25 is connected, advantageously
but not only of the linear type.
[0032] The pressure detection device can normally be present in cooperation with the discharge
pan 20 so as to perform other functions connected with the functioning of the washer
machine 16.
[0033] The device 10 also comprises a command unit 26, of the programmable type, which activates
the regeneration cycles, counts the number and determines the need for reintegration.
The command unit 26 is connected at least to the linear pressure sensor 25, in order
to receive therefrom the information relating to the discharge of water into the pan
20, and to a luminous indicator 27 to warn the user of the need for reintegration.
[0034] The salt tank 17 is normally filled with water and can be selectively opened from
the outside by means of a stopper 22, so as to allow the user to introduce inside
it a desired quantity of salt so as to form a saline solution with a determinate level
of saturation.
[0035] The ion exchange resin tank 19 determines the decalcification of the running water
used for washing, while the saline solution allows the regeneration thereof during
said programmed cycles.
[0036] The tank for the regeneration water 21 allows to create cyclically a flow of clean
water used to regenerate the resins, that is, to remove from them, after passing through
the saline solution, the calcium and magnesium ions with which they became enriched
due to the passage of the running water.
[0037] In this way, with every regeneration cycle, the resins re-acquire their functionality,
giving up the calcium to the quantity of saline solution used, which is then discharged
through the pan 20, while the saline solution is progressively diluted.
[0038] The pan 20 is connected to the discharge network and said linear pressure sensor
25 cooperates with it.
[0039] The linear sensor 25 is able to measure the quantity of salt reintegrated into the
tank 17, measuring the quantity of water that pours into the pan 20, overflowing from
the tank 17 following the unloading of the salt. Moreover, the linear sensor 25 performs
the dynamic measurement of the increase in the level of water inside the pan 20, and
thus also detects the speed of unloading.
[0040] The linear sensor 25 is therefore able to discriminate whether the flow of water
into the pan 20 derives from the unloading of salt into the tank 17, rather than a
flow caused for example by the emptying of a saucepan or a glass.
[0041] The method according to the invention takes into account the number of regeneration
cycles counted after each reintegration has occurred.
[0042] The regeneration cycle can occur in two different ways, according to the structural
configuration of the components. Two different configurations are shown in figs. 2
and 3.
[0043] In the configuration in fig. 2, the device 10 comprises a valve 23 disposed between
the regeneration water tank 21 and the salt tank 17 which, when closed, prevents the
passage of the regeneration water. A non-return valve 29 is also present between the
salt tank 17 and the resin tank 19.
[0044] In this solution, at pre-determined intervals, the valve 23 is opened by the command
unit 26 in order to allow the clean water present in the regeneration tank 21 to enter
the salt tank 17 and partly replace the saline solution which goes to regenerate the
resin tank 19. This configuration allows to open the salt tank 17 by removing the
stopper 22 without the saline solution leaking from the tank 17.
[0045] In the configuration in fig. 3, the closing valve 123 is positioned between the salt
tank 17 and the resin tank 19.
[0046] In this case, with every regeneration cycle the valve 123 is opened so as to determine
the flow of a determinate quantity of saline solution into the resin tank 19, while
a corresponding quantity of clean water from the regeneration tank 21 takes its place.
[0047] To determine when the salt is to be topped up, the invention provides the following
steps.
[0048] Starting from an initial condition in which the salt tank 17 is full of water, a
determinate quantity of salt is added, so as to create the saline solution inside
the tank 17.
[0049] The addition of salt to the tank 17 determines the overflow from the tank 17 of a
quantity of water corresponding to the quantity of salt introduced, and this water
pours into the discharge pan 20. The linear pressure sensor 25 detects the dynamic
increase in the level and measures the quantity of water overflowing, so that the
command unit 26 is able to deduce the measurement of the quantity of salt introduced.
[0050] In this way, the command unit 26 fixes a zero time to start the backward count-down
of the quantity of salt, starting from the value measured by means of the linear sensor
25.
[0051] Assuming that the quantity of salt removed with every regeneration cycle is known,
the command unit 26 is able to count how many regeneration cycles are necessary to
reduce the quantity of salt in the tank 17 to a pre-established minimum value in order
to indicate the need for reintegration.
[0052] This count is effected by subtracting on each occasion, from the quantity of salt
introduced initially into the tank 17, the quantity of salt removed with every regeneration
cycle.
[0053] According to a variant, the calculation of the number of regeneration cycles also
takes into account the progressive reduction in the level of saturation of the saline
solution.
[0054] In this way, once a number of regeneration cycles has been reached, which is near
the maximum possible number, the command unit 26 warns the user, for example by means
of the visual indicator 27 and/or by means of an acoustic indicator, that he must
reintegrate the salt in the tank 17.
[0055] At this point, when the salt is again reintegrated, the linear pressure sensor 25
dynamically detects that a certain quantity of water, corresponding to the salt introduced,
has flowed into the pan 20, and again zeroes the counting of the command unit 26.
[0056] It is clear, however, that modifications and/or additions of parts or steps may be
made to the method and device 10 as described heretofore, without departing from the
scope of the present invention.
1. Method to indicate the need for reintegration of a regenerating substance of the anti-calcium
function in a washer machine (16), wherein the washer machine (16) comprises at least
a containing tank (17) for a regenerating substance, a discharge pan (20) and a command
unit (26) suitable to activate, after a defined number of washing cycles, a regeneration
cycle using said regenerating substance,
characterized in that the method provides the following steps:
- a meter in the command unit (26) is zeroed at the moment a performed reintegration
of the regenerating substance is detected in said tank (17);
- the quantity of said regenerating substance unloaded into the tank (17) is measured,
by measuring the quantity of water that flows into said pan (20) following said reintegration;
- the number of regeneration cycles performed is progressively counted, starting from
the last reintegration performed, and the quantity removed with every regeneration
cycle is deducted from the measured quantity of regenerating substance introduced
into said tank (17);
- the need for reintegration is indicated after a number of regeneration cycles such
that the regenerating substance remaining in the tank (17) has reached a pre-established
minimum level.
2. Method as in claim 1, characterized in that the measurement of the quantity of water that flows into said pan (20) due to the
reintegration of the regenerating substance is performed by means of a pressure sensor
(25) associated with said pan (20).
3. Method as in claim 2, characterized in that it provides to use a linear pressure sensor (25).
4. Method as in claim 3, characterized in that said linear pressure sensor (25) also detects the dynamics of the flow of the water
into the pan (20) in order to discriminate whether said flow is caused by the unloading
of the regenerating substance into the tank (17) or by other causes.
5. Device to indicate the need for reintegration of a regenerating substance of the anti-calcium
function in a washer machine (16) comprising at least a containing tank (17) for a
regenerating substance, a discharge pan (20) and a command unit (26) suitable to activate,
after a defined number of washing cycles, a regeneration cycle using said regenerating
substance,
characterized in that it comprises:
- a pressure sensor (25) associated with said discharge pan (20) and able to measure
the quantity of regenerating substance unloaded into the tank (17) during said reintegration
by measuring the quantity of water poured into said pan (20);
- a meter, in said command unit (26), which is zeroed at the moment said reintegration
is performed, and starts the progressive count of the number of regeneration cycles
performed starting from the last reintegration performed, removing from the measured
quantity of regenerating substance introduced into the tank (17) a quantity removed
with every regeneration cycle;
- a visual (27) and/or acoustic indicator, activated by said command unit (26), to
indicate the need for reintegration after a number of regeneration cycles such that
the remaining regenerating substance has been reduced to a pre-established value for
reintegration.
6. Device as in claim 5, characterized in that said pressure sensor (25) is of the linear type in order to detect the dynamics of
the flow of water into said discharge pan (20) and to discriminate whether said flow
has been caused by the unloading of the regenerating substance into the tank (17)
or by other causes.
7. Device as in claim 5, characterized in that said pressure sensor (25) is a pressure switch.