[0001] The present invention refers to a household-type clothes washing machine comprising
a programme sequence control switch to control the actuation of the various process
cycles to be performed by the machine, and a number of control devices provided to
ensure correct operation of the same machine according to pre-set process parameters.
[0002] Clothes washing machines are generally known to be equipped with a safety interlock
arrangement provided to prevent the loading door from being able to be opened when
the machine is operating.
[0003] A first type of such door interlock arrangement is generally adapted to enable the
loading door to only be opened, upon conclusion of a process cycle, after a certain
delay time has elapsed so as to allow the user to reach into the drum under conditions
of greater safety.
[0004] Such an arrangement generally consists of some electromechanical device comprising
mainly a catch or similar contrivance which is adapted to lock the loading door in
its closed position under the action of a moving arm associated to a delaying element
of the positive temperature coefficient (PTC) type, as this is described for instance
in the patent specification GB-A-2 128 283.
[0005] Such a PTC-type element is energized electrically, so as to command the safety arrangement
accordingly, through appropriately provided controlled-type switches which indesirably
complicate the overall control system of the machine. As a matter of fact, such switches
may consist of appropriately provided contacts of the programme sequence control switch
(in electromechanical solutions) or relays and/or Triacs (in electronic solutions),
with corresponding driving and filter circuits associated thereto, which not only
add to the overall costs of the product, but also reduce the reliability of the machine
owing to the increased number of component parts subject to possible failure or breakdown.
[0006] Another type of door interlock arrangement is defined as "instantaneous" due to the
fact that the loading door can be opened immediately upon actuation of an electric
control element, whereas the opening of the door will in any case only be allowed
if the drum is not rotating any longer, the level of the water is below the lower
edge of the door and the temperature of the water is below a given value (for instance,
40°C).
[0007] Clothes washing machines are also generally known to be provided with a water flow
distributing arrangement which, when directed by the programme sequence control switch
to do so, diverts the flow of incoming water into the various compartments provided
in the detergent dispenser to hold the detergents and the various additives and rinsing
aids required to perform the washing process. The systems that have been used up to
now to correctly shift or direct the water flow distributor in correspondence of the
required compartment are based on logical position codings capable of being implemented
and carried out in a variety of manners. Anyway, all such systems call for a number
of lines of the microprocessor associated to the programme sequence control switch
to be occupied, as well as the use of low-voltage powered reading elements, the reliability
of which is going to decrease with the time owing to problems deriving for instance
from an oxidation of their electrical contacts. A solution of this kind is disclosed
in the patent specifications EP 0 253 710 and EP 0 504 545.
[0008] It would therefore be desirable, and it is actually a main purpose of the present
invention, that the part count of control and adjustment arrangements of clothes washing
machines be reduced to a minimum, while simplfying the overall circuitry and boosting
the reliability and safety of the component parts thereof.
[0009] The solution according to the present invention, as this is recited in the appended
claims, substantially proposes the use of the electronic switch, ie. the Triac, which
is normally present in the clothes washing machine to control the motor driving the
rotating drum, as a general element controlling various critical component parts of
the machine, such as the PTC element of the door interlock arrangement and position
contacts provided to control the distribution of the inlet water flow and identify
the individual operating phases of the washing cycles which the machine is going through.
[0010] Characteristics and advantages of the present invention will be more clearly understood
from the description that is given below by way of non-limiting example with reference
to the accompanying drawings, in which
- Figure 1 is a view of a simplified wiring diagram for a clothes washing machine provided
with a traditional type of PTC-based door interlock arrangement, as improved according
to the present invention;
- Figure 2 is a view of a wiring diagram which is similar to the one shown in Figure
1, but intended for a clothes washing machine provided with a door interlock arrangement
of the instantaneous type.
[0011] In Figure 1, the reference numeral 1 is used to indicate the main on/off switch of
the clothes washing machine, the reference numeral 2 to indicate the electrical contact
of the door interlock device, the reference numeral 3 to indicate the PTC element
of the door interlock arrangement, the reference numeral 4 to indicate the electronic
control module of the clothes washing machine, the reference numeral 5 to indicate
the general relay of the machine, the reference numeral 6 to indicate a tachometer
adapted to measure the revolutions per minute of the driving motor and, hence, of
the rotating drum of the machine, the reference numeral 7 to indicate the stator of
the motor rotatably driving the rotating drum of the machine, the reference numeral
8 to indicate the rotor of the same motor, the reference numeral 9 to indicate the
electric portion of the programme sequence control switch governing the operational
elements of the clothes washing machine and, in particular, the inlet water flow distributing
arrangement (not shown), the reference numeral 10 to indicate the power contacts of
said programme sequence control switch, the reference numeral 11 to indicate the wiping
contacts equipping the programme sequence control switch to control the positioning
of the inlet water flow distributing arrangement, the reference numeral 12 to indicate
an electrical RFI suppressing filter, the reference numeral 13 the driving motor of
the programme sequence control switch, the reference numeral 14 to indicate the various
connections of the programme sequence control switch with the functional elements
of the machine (such as electromagnetic valves, pumps and the like), the reference
numeral 15 to indicate the wiping contacts equipping the programme sequence control
switch to control said functional elements of the machine, the reference numeral 16
to indicate the relay controlling the reversing action of the rotating drum, the reference
numeral 17 to indicate the microprocessor included in the electronic control module
4 of the machine, the reference numeral 18 to indicate the electronic switch (Triac)
of the motor driving the programme sequence control switch, and the reference numeral
19 to indicate the electronic switch (Triac) of the motor driving the rotating drum
of the machine.
[0012] It should be noticed that, according to the present invention, the wiping contacts
11 are additionally used to identify, through counting, all of the electrical positions
taken by the programme sequence control switch while going through the various cycles,
as this will be explained in greater detail further on.
[0013] In Figure 2, which illustrates the electrical schematics of a clothes washing machine
equipped with a door interlock arrangement of the instantaneous type, the only variant
appearing as compared to Figure 1 is represented by the coil 22 (which replaces the
PTC element 3) of the door interlock arrangement and the corresponding electrical
connection with the electronic control module 4. All other component parts are identical
to the ones appearing in Figure 1, so that they are indicated using the same reference
numerals.
[0014] All such elements are normally provided and used in the control and regulation circuitry
of an electronically controlled clothes washing machine.
[0015] According to the present invention, however, some of such elements are connected,
in the two illustrated embodiments, in a new and original manner to reach the previously
indicated aims and advantages.
[0016] In Figure 1, in fact, the PTC element 3 of the door interlock arrangement is connected
to the Triac 19 via a connection terminal 24 of the electronic control module 4. The
drum driving motor 7, 8, further to its normal connection with its corresponding Triac
19, via a contact 25 of the programme sequence control switch, and the reversing relay
16, is also connected, via said reversing relay 16, with the general relay 5 and the
electric contact 2 of the door interlock arrangement, via a switch-over contact 26.
[0017] For the door to be effectively locked, it is necessary that the PTC element 3 be
energized either continuously or intermittently, whereas in the latter case the interval
shall however be shorter than its release time (usually ≤1.5 minutes). By taking advantage
of this delay time, it is therefore possible to keep the door locked by simply letting
the drum of the washing machine rotate according to an appropriately selected rhythm.
[0018] The solution according to the present invention, however, enables the door to be
kept locked even without the need for the drum to be driven. This is possible through
the contact 26 being switched over so as to divert the power supply from the driving
motor 7, 8 to the relay 5. In this particular situation, all other electric elements
of the washing machine are de-energized, so that such a condition may be only brought
about in well-determined phases of an operational cycle (for instance, in the "pre-soak"
phase, in which the clothes, and in particular the delicate ones, have to be kept
immersed in water for a certain period of time, without any rotation of the drum).
[0019] Should the Triac 19 of the drum driving motor 7, 8 suffer a short-circuit condition,
the microprocessor 17 will activate the relay 5 by switching over the contact 26 so
as to remove the power supply from the motor 7, 8. The door of the clothes washing
machine will then be able to be opened after the inherent delay time of the PTC element
3 has been duly allowed to elapse. In other words, it can conclusively be said that
when the relay 5 is de-energized (switch-over contact 26 in the position shown in
Figure 1) and the Triac 19 is operating regularly, both the door interlock arrangement
2, 3 and all of the functional elements of the washing machine are activated. When
on the contrary the relay 5 is energized (contact 26 switched over from the position
shown in Figure 1) along with the Triac, the door interlock arrangement 2, 3 keeps
being activated together with the driving motor 13 of the programme sequence control
switch, while all other functional elements of the washing machine are however de-energized,
ie. separated from the power supply.
[0020] In the embodiment illustrated in Figure 2, in which a door interlock arrangement
of the so-called instantaneous type is used, the specific situations are different,
but they anyway ensure the same function. In fact, if the Triac 19 suffers a short-circuit
condition, the microprocessor 17 will detect such a condition on the basis of the
signal delivered by the tachometer 6. Under the circumstances, the microprocessor
17 cannot energize the relay 5 and, as a consequence, de-energize the drum driving
motor 7, 8, since the door could then be opened immediately. To switch off and stop
the motor 7, 8, the microprocessor 17 will therefore energize the driving motor 13
of the programme sequence control switch until the contact 25 is brought to its opening
position. The drum driving motor 7, 8 is in this way de-energized and, upon the drum
coming to a standstill, the microprocessor 17 will activate the relay 5 (by switching
over the contact 26 from the position shown in Figure 2), thereby energizing the coil
22 that will open the switch 2 of the drum loading door.
[0021] Therefore, it can conclusively be said that when the relay 5 is energized (contact
26 switched over from the position shown in Figure 2) and the Triac 19 is not operating,
the door interlock arrangement is energized, while the functional elements of the
washing machine are separated from the power supply. When the relay 5 is on the contrary
de-energized (contact 26 in the position shown in Figure 2) and the Triac is in any
of its conditions, both the door interlock arrangement and the functional elements
of the washing machine are energized.
[0022] The electric circuits appearing in Figures 1 and 2 emphasize a further innovatory
feature which is capable of increasing both the simplicity and the reliability of
the control arrangements of a clothes washing machine. As it can be noticed in the
Figures, the wiping contacts 11 controlling the positioning of the inlet water flow
distributor are connected to the electronic control module 4 and, as a consequence,
the microprocessor 17, via two connection lines 20, 21 only.
[0023] Such a solution enables, through only two 220-volt signals coming from the contacts
11, various positions corresponding to the main phases of the operational cycles of
the machine (ie. pre-wash/rinses, main wash, drying, etc.) to be recognized. Within
each one of such phases there may be several positions of electrical actuation which
the microprocessor 17 is able to recognize through a simple counting starting from
the first one.
[0024] During a cycle, the microprocessor 17 is capable to recognize the starting position
of a phase and can shift the corresponding actuator to the desired position; any subsequent
shifting will be made forward and/or backward with respect to that position, using
per sè known means, based on said counting.
[0025] Should there be a power supply failure for any reason whatsoever, the microprocessor
17, after the power supply has been duly restored, will start from the current position
and shift the inlet water flow distributor backward until a change of phase is read.
This is needed by the microprocessor 17 in order to be able to identify the position
in a univocal manner. A solution like this, which may for instance comprise a mechanical
phase indicator means (flange), arranged coaxially with respect to the camshaft of
the programme sequence control switch, and a clutch means being adapted to only act
when the shaft is rotated clockwise, enables such an identification of position to
be made without altering the associated phase indication.
[0026] Conclusively, the described solution enables various positions (of the inlet water
flow distributor, the current cycle phase being performed, the electric contacts of
the various functional elements of the machine, and the like) to be recognized by
only using two connection lines to the microprocessor. Furthermore, the signals coming
from the water flow distributor position contacts 11 are more reliable since the latter
are energized with alternating current at 220 Volts reducing oxidation problems.
[0027] It will be appreciated that the described circuits may undergo any modification or
variation as considered to be appropriate, without departing from the scope of the
present invention as defined in the appended claims.
1. Clothes washing machine of the rotating-drum type, comprising at least an arrangement
(2,3) adapted to lock the drum loading door, an inlet water flow distributor to direct
selectively the water flow to the various compartments of the detergent dispenser,
a motor (7,8) to rotatably drive the drum, an electromechanical programme sequence
control switch (9), all said components being connected to an electronic control arrangement (4) comprising a main relay (5), a drum rotation
reversing relay (16), a microprocessor (17) and an electronic motor-control switch
(19), characterized in that the driving motor (13) of the programme sequence control switch (9) is controlled, via the microprocessor (17) and the main relay (5), by two position signals transmitted on two connection lines (20,21) coming from respective contacts (11) of the programme sequence control switch,
as well as by the door interlock arrangement (2,3) and the electronic switch (19)
of the motor (7,8).
2. Clothes washing machine according to claim 1, characterized in that the two position signals of the contacts (11), in combination with the counting performed
by the microprocessor (17), further constitute the means for recognizing the phases
of the operational cycle performed by the machine.
3. Clothes washing machine according to claim 1 or 2, characterized in that the two position signals, in combination with the counting performed by the microprocessor
(17), are associated to the motion of the motor (13) to form the means for identifying
the phase of the cycle in the case of the power supply to the washing machine being
restored after a failure.
4. Clothes washing machine according to claim 1, wherein the door interlock arrangement
is of the delayed type, characterized in that the door interlock arrangement (2, 3) and the drum driving motor (7, 8) are connected
to the main relay (5) via a switch-over contact (26).
5. Clothes washing machine according to claim 1, wherein the door interlock arrangement
is of the instantaneous type, characterized in that the coil (22) of the door interlock arrangement is directly connected to the electronic
switch (19) of the motor (7, 8) via a terminal (24) of the electronic control module
(4), and is further connected to the main relay (5) via a switch-over contact (26).
1. Waschmaschine vom Drehtrommel-Typ, die mindestens eine zum Verschließen der Trommel-Beladetüre
geeigneten Anordnung (2, 3), einen Einlaßwasserstrom-verteiler zum wahlweisen Lenken
des Wasserstromes zu den verschiedenen Fächern des Detergentien-Abgebers, einen Motor
(7, 8) zum Dreh-Antrieb der Trommel und einen elektromechanischen Programmfolge-Steuerschalter
(9) umfaßt, welche Komponenten alle mit einer elektronischen Steueranordnung (4) mit
einem Hauptrelais (5), einem Trommeldrehungs-Umschaltrelais (16), einem Mikroprozessor
(17) und einem elektronischen Motorsteuerschalter (19) verbunden sind,
dadurch gekennzeichnet, daß der Antriebsmotor (13) des Programmfolge-Steuerschalters (9) über den Mikroprozessor
(17) und das Hauptrelais (5) durch Zweipositions-Signale gesteuert wird, die an zwei
Verbindungsleitungen (20, 21) übertragen werden, welche von jeweiligen Kontakten (11)
des Programmfolge-Steuerschalters kommen, wie auch durch die Türverriegelungs-Anordnung
(2, 3) und den elektronischen Schalter (19) des Motors (7, 8).
2. Waschmaschine nach Anspruch 1, dadurch gekennzeichnet, daß die Zweipositions-Signale der Kontakte (11) in Kombination mit dem durch den
Mikroprozessor (17) ausgeführten Zählvorgang weiter das Mittel zum Erkennen der Phasen
des durch die Maschine ausgeführten Betriebszyklus bilden.
3. Waschmaschine nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Zweipositions-Signale in Kombination mit dem durch den Mikroprozessor (17)
ausgeführten Zählvorgang der Bewegung des Motors (13) zugeordnet sind, um das Mittel
zur Identifizierung der Phase des Zyklus zu bilden, falls die Stromversorgung der
Waschmaschine nach einem Versagen wieder hergestellt ist.
4. Waschmaschine nach Anspruch 1, bei der die Türverriegelungs-Anordnung vom Verzögerungstyp
ist, dadurch gekennzeichnet, daß die Türverriegelungs-Anordnung (2, 3) und der Trommel-Antriebsmotor (7, 8) mit
dem Hauptrelais (5) über einen Umschalterkontakt (26) verbunden sind.
5. Waschmaschine nach Anspruch 1, bei der die Türverriegelungs-Anordnung vom Momentantyp
ist, dadurch gekennzeichnet, daß die Spule (22) der Türverriegelungs-Anordnung direkt mit dem Elektronikschalter
(19) des Motors (7, 8) über eine Klemme (24) des elektronischen Steuermoduls (4) verbunden
ist und weiter über einen Umschalterkontakt (26) mit dem Hauptrelais (5) verbunden
ist.
1. Machine à laver le linge du type à tambour rotatif, comprenant au moins un agencement
(2, 3) adapté pour verrouiller la porte de chargement du tambour, un distributeur
d'écoulement d'eau d'admission pour diriger, de manière sélective, l'écoulement d'eau
vers les divers compartiments du distributeur de détergent, un moteur (7, 8) pour
entraîner en rotation le tambour, un commutateur de commande de séquence de programme
électromécanique (9), lesdits composants étant tous connectés à un agencement de commande
électronique (4) comprenant un relais principal (5), un relais d'inversion de sens
rotation de tambour (16), un microprocesseur (17) et un commutateur de commande de
moteur électronique (19), caractérisée en ce que le moteur de commande (13) du commutateur
de commande de séquence de programme (9) est commandé, via le microprocesseur (17)
et le relais principal (5), par deux signaux de position transmis sur deux lignes
de connexion (20, 21) provenant de contacts (11) respectifs du commutateur de commande
de séquence de programme, ainsi que par l'agencement de verrouillage de porte (2,
3) et le commutateur électronique (19) du moteur (7, 8).
2. Machine à laver le linge selon la revendication 1, caractérisée en ce que les deux
signaux de position des contacts (11), en combinaison avec le comptage effectué par
le microprocesseur (17), constituent, de plus, les moyens destinés à reconnaître les
phases du cycle de fonctionnement exécuté par la machine.
3. Machine à laver le linge selon la revendication 1 ou 2, caractérisée en ce que les
deux signaux de position, en combinaison avec le comptage effectué par le microprocesseur
(17), sont associés au mouvement du moteur (13) pour former les moyens destinés à
identifier la phase du cycle dans le cas du rétablissement de l'alimentation de la
machine à laver après une panne.
4. Machine à laver le linge selon la revendication 1, dans laquelle l'agencement de verrouillage
de porte est du type à retard, caractérisée en ce que l'agencement de verrouillage
de porte (2, 3) et le moteur d'entraînement de tambour (7, 8) sont connectés au relais
principal (5) via un contact de commutation (26).
5. Machine à laver le linge selon la revendication 1, dans laquelle l'agencement de verrouillage
de porte est du type instantané, caractérisée en ce que la bobine (22) de l'agencement
de verrouillage de porte est directement connectée au commutateur électronique (19)
du moteur (7, 8) via une borne (24) du module de commande électronique (4) et est,
de plus, connectée au relais principal (5) via un contact de commutation (26).