Dishwashing machine with garbage shredding apparatus

Description

[0001] The present invention refers to a dishwashing machine of the type incorporating a garbage shredder adapted to enable the soil being removed from the dishes and the other washload items in general to be cut into tiny particles under corresponding improvement in the performance and effectiveness of the filtering system and, ultimately, the entire dishwashing machine.

[0002] Garbage shredding apparatuses are generally known to usually comprise an array of knives adapted to rotate with respect to an array of stationary blades. As such, they are also generally known as being subject to jamming due to the presence of particularly hard soil matters, such as chicken bones or the like, which practically prevent them from operating in a correct manner.

[0003] This problem is of particularly great significance in dishwashing machines, in which, owing mainly to problems deriving from the need to reduce space requirements, the available power for driving the garbage shredding apparatus is relatively low, while particularly tough soil matters capable of causing the garbage shredding apparatus to jam are on the other hand quite frequently present inside such machines.

[0004] In view of minimizing the likelihood of a jamming of the rotating parts, a hydraulically operated garbage shredding apparatus has been proposed, such as the one that is for instance described in US-A-6 012 662. In this solution, an alternating piston is driven by water under pressure in an annular chamber and is connected to the rotating knives of the garbage shredding apparatus. A valve is provided with an alternating control piston so as to be able to selectively divert the water under pressure in said annular chamber on to opposite sides of the actuating piston. As a result, the rotating knives are operated so as to be capable to rotate in opposite directions, in particular when they happen to be jammed by particularly tough soil matters. Conclusively, it can therefore be said that the garbage shredder is capable of working effectively under any operating conditions.

[0005] On the other hand, however, a garbage shredder of the above described type is relatively bulky, ie. needs quite a lot of space, and requires a connection to a water supply line capable of supplying water at a particularly high pressure (as is the case in the USA, for instance). It in fact becomes practically ineffective if it is connected to a water supply line with a rather reduced supply pressure, eg. as this is the case in European counties, or as in US 3 401 892.

[0006] In any case, a dishwashing machine incorporating a garbage shredder of this kind would unavoidably imply a really excessive water usage.

[0007] It therefore is a purpose of the present invention to provide a dishwashing machine incorporating a garbage shredding apparatus which is particularly effective, compact and adapted to favour a substantial energy saving effect.

[0008] A further purpose of the present invention is to provide a dishwashing machine of the above cited kind, which is provided with a filtering system that is particularly simple, rational and effective, such as to be instrumental in substantially improving the washing performance capabilities of the dishwashing machine.

[0009] Another purpose yet of the present invention is to provide a dishwashing machine of the above cited kind, which is provided with a water circuit that is particularly adapted to boost the performance capabilities of the built-in garbage shredding apparatus.

[0010] According to the present invention, these aims are reached in a dishwashing machine with a built-in garbage shredding apparatus embodying the characteristics as recited and defined in the appended claims.

[0011] Anyway, features and advantages of the present invention may be more readily understood from the description that is given below by way of nonlimiting example with reference to the single accompanying drawing, which is a partial and schematic view of a preferred embodiment of the dishwashing machine according to the present invention.

[0012] With reference to said Figure, the dishwashing machine mainly comprises a washing vessel 1 (shown only partially) provided on its bottom portion with a water collecting sump 2, to which there is connected the suction side 3 of a circulation pump 4, the delivery side 5 of which is connected to at least a rotating spray arm 6 so as to spray washing liquor on to the washload items arranged in appropriate support racks (not shown for reasons of greater simplicity).

[0013] The washing vessel 1 also accommodates, below the rotating spray arm 6, a filtering system arranged in the flow-path of the washing liquor which, upon having been so sprayed on to the washload items, collects into the sump 2 in view of being taken in again by the circulation pump 4.

[0014] In the example being described here, said filtering system comprises a planar or frusto-conical, preferably coarse-mesh filter portion 7, which is provided with a mouth 8 between the edge of which and the bottom of the sump 2 there extends the main filter portion, which is generally indicated at 9 in the Figure.

[0015] The filter 9 has preferably a very fine mesh structure and is the section of the filtering systems that most of all contributes to the retention of the soil particles from the flow of the water circulated by the pump 4. The filter 9 has substantially a frusto-conical (as shown in the Figure, actually), cylindrical or a similar shape, and is adapted to be driven rotatably, substantially about its own main axis, by the rotor 11 of a garbage shredding apparatus which is incorporated in the dishwashing machine and is generally indicated at 10 in the Figure.

[0016] In a preferred manner, the garbage shredding apparatus 10 comprises knives capable of rotating with respect to an array of stationary blades of the type described in US-A-6 109 551.

[0017] The filter 9 is rotatably integral with a driving shaft 12 of the rotor 11, to which it is connected through a frusto-conical flange 13 that forms for the garbage shredder 10 a kind of inlet hopper communicating with the washing vessel 1 upstream of the filtering system 7, 9.

[0018] The garbage shredder 10 also comprises an outlet aperture 14, preferably provided in the bottom of the water collecting sump 2, from which there branches off an outlet conduit 15 provided with a drain pump 16. In other words, the outlet conduit 15 of the dishwashing machine branches off the sump 2 in correspondence of the garbage shredder 10.

[0019] In a preferred manner, the garbage shredder 10 extends from the bottom of the sump 2 up to the inlet hopper 13 with a side wall that is substantially defined by an auxiliary coarse-mesh filter 17 that is substantially surrounded by the main filter 9, of which it advantageously limits the possibility of getting clogged.

[0020] Via the shaft 12, the rotor 11 of the garbage shredder 10 is connected to an electric-bi-directional motor 18, which is controlled by sensor means 19 adapted to either directly or indirectly detect the resisting torque applied to the rotor 11 and to cause the same rotor to reverse the direction of rotation thereof when the resisting torque is detected to exceed a pre-determined threshold value.

[0021] Said sensor means 19 may include a threshold-value comparator built into the programme sequence control unit of the machine (not shown in the Figure for reasons of greater simplicity, and comprising for instance a Motorola 68HC705 microprocessor) and driven by means of an input 20 with a signal that is indicative of the above mentioned resisting torque. Such a signal may for instance be the current absorbed by the motor 18, or the phase difference between the voltage and the current of the motor 18, or the like.

[0022] In any case, should it happen that the rotor 11 of the garbage shredder tends to become jammed due to the presence of a foreign matter that proves particularly tough and is apt to give rise to a resisting torque in excess of a pre-determined value, the sensor 19 causes (through the programme sequence control unit of the machine) the rotor 11 to reverse its direction of rotation, thereby ensuring a maximum extent of effectiveness in the operation of the garbage shredder 10.

[0023] Irrespective of this operational feature thereof, the rotor 11 is preferably driven by the motor 18 so as to be capable to regularly reverse its direction of rotation in a cyclic manner, eg. upon each complete revolution thereof.

[0024] In all cases, as already mentioned earlier in this description, the rotor 11 is arranged to rotatably drive also the filter 9, and the latter is associated to at least an adjacent stationary nozzle 21 connected to the delivery side 5 of the circulation pump 4 via a calibrated-bore branch-pipe 22. As a result, when the pump 4 is operating and the filter 9 is so driven to rotate, substantially the entire surface of said filter 9 is flushed by a counter-flow jet of water, coming from said nozzle 21, which advantageously removes from, ie. flushes off the same filter the soil particles that are gradually retained by the same filter. It can be readily appreciated that such a rotation of the filter 9 enables an optimum self-cleaning effect of the same filter to be obtained, although making use of just a single nozzle 21 and, therefore, without any substantial additional water usage.

[0025] In a preferred manner, the outlet conduit 15 comprises, downstream of the drain pump 16, a flow-diverting device 24 from which a re-circulation pipe 23 communicating with the interior of the washing vessel 1 branches off. In a preferred manner, furthermore, such a diverting device 24 is normally in a condition in which the drain pump 16 is in communication with the sole outlet conduit 15.

[0026] At the beginning of an operating cycle of the dishwashing machine, eg. during a pre-wash phase (or, anyway, when coarse soil particles happen to be still deposited on the washload items), the programme sequence control unit of the machine determines the operation of the circulation pump 4 and the drive motor 18; it furthermore commands the diverter 24 to temporarily switch over to an operational position in which the delivery side of the drain pump 16, which is also operated temporarily, is in communication with the re-circulation pipe 23. As a result, the soil particles that are flushed off the washload items due to the action of the rotating spray arm 6 are shredded by the garbage shredder 10 and recirculated by the pump 16 through the pipe 23 that conveys them again into the washing vessel 1 and, then, again through the garbage shredder 10. In other words, in this temporary phase, the re-circulation pipe 23 enables a real closed-loop water-flow circuit, passing through the garbage shredder 10, to be realized for the soil particles conveyed by a flow of water generated by the drain pump 16, which therefore performs a twofold task.

[0027] This most advantageously enables the soil particles to be shredded most finely, and this in turn enables the dishwashing machine to subsequently carry out a washing phase (which may also be a substantially traditional one) under the best conditions in view of obtaining an ideal washing effect.

[0028] In an appropriate subsequent phase of the washing cycle being performed by the machine, the programme sequence control unit of the machine may of course cause the flow diverter 24 to switch back into its normal resting position, so as to enable the soiled water contained in the washing vessel 1 to be let off through the outlet pipe 15. The resulting absence of soil on the bottom of the washing vessel 1 brings about the quite important advantage that the subsequent washing, rinsing and/or drying phases of the cycle will be able to be carried out with completely clean water and in a substantial absence of bad odours.

[0029] As for the rest, the general operation of the dishwashing machine may be of a substantially traditional kind, so that it shall not be dealt with here any further for reasons of greater simplicity.

[0030] It shall be appreciated that the dishwashing machine that has been described here by mere way of example may be the subject of a number of modifications without departing from the scope of the present invention.

Claims

1. Dishwashing machine comprising a built-in garbage shredding apparatus (10) incorporated therein that has an inlet in communication with the washing vessel (1) of the machine and an outlet (14) connected to an outlet conduit (15), said garbage shredding apparatus (10) comprising in turn a rotor (11) adapted to selectively rotate in the two opposite directions, characterized in that said rotor (11) is driven by a bi-directional electric motor (18), which is controlled by sensor means (19) adapted to detect the resisting torque being applied to the rotor (11) of the garbage shredding apparatus (10) and to cause the same rotor (11) to reverse the direction of rotation thereof when the resisting torque is detected to exceed a pre-determined threshold value.

2. Dishwashing machine according to claim 1, characterized in that said sensor means (19) comprise a threshold-value comparator driven by a signal that is indicative of said resisting torque, such as the current absorbed by said electric motor (18), the phase difference between the voltage and the current of the same motor (18), or the like.

3. Dishwashing machine according to claim 1, characterized in that the rotor (11) of said garbage shredding apparatus (10) is normally driven by said motor (18) so as to reverse its direction of rotation cyclically.

4. Dishwashing machine according to claim 1, comprising a filtering system (7, 9, 17) arranged in the flow-path of the washing water circulated by a circulation pump (4), characterized in that at least a main portion (9) of said filtering system (7, 9, 17) is adapted to be rotatably driven jointly with the rotor (11) of the garbage shredding apparatus (10) and is associated to at least a nozzle (21), or the like, adapted to be supplied by said circulation pump (4) so as to issue a counter-flow jet of water capable of flushing and cleaning said portion (9) of said filtering system.

5. Dishwashing machine according to claim 4, characterized in that said nozzle (21) is connected to the delivery side (5) of the circulation pump (4) via a calibrated-bore branch pipe (22).

6. Dishwashing machine according to claim 4, characterized in that said main portion (9) of the filtering system is substantially frusto-conical or cylindrical in its shape and is rotatably joined with said rotor (11) of said garbage shredding apparatus (10) so as to be capable of rotating, about its own main axis, integrally therewith.

7. Dishwashing machine according to claim 4, characterized in that said garbage shredding apparatus (10) has at least a wall that is substantially defined by an auxiliary filter (17), which is substantially surrounded by said main filter (9).

8. Dishwashing machine according to claim 1, characterized in that said outlet conduit (15) comprises, downstream of a drain pump (16), normally inoperative flow diverting means (24) adapted to selectively connect, during a temporary phase, the delivery side of said drain pump (16) with a re-circulation pipe (23) communicating with the interior of the washing vessel (1), in such a manner as to bring about a closed-loop water-carrying circuit, passing through said garbage shredding apparatus (10), for the soil particles being conveyed by a flow of water generated by said drain pump (16).

9. Dishwashing machine according to claim 8, characterized in that, upon conclusion of said temporary phase, the drain pump (16) is temporarily operated to let off, through said diverting means (24), water containing the soil particles that have previously been most finely shredded by said garbage shredding apparatus (10)

Ansprüche

1. Geschirrspülmaschine, welche eine in sie eingebaute Einbauvorrichtung zur Speiserestzerkleinerung (10) enthält, welche einen Einlass in Verbindung mit dem Waschbehälter (1) der Maschine und einen mit einer Abflussleitung (15) verbundenen Auslass (14) aufweist, wobei die besagte Vorrichtung für die Speiserestzerkleinerung (10) ihrerseits einen Rotor (11) enthält, welcher dergestalt ausgelegt ist, dass er sich wahlweise in zwei entgegengesetzten Richtungen dreht, dadurch gekennzeichnet, dass besagter Rotor (11) von einem bidirektional laufenden Elektromotor (18) angetrieben wird, welcher durch Sensormittel (19) angesteuert wird, welche so ausgelegt sind, dass sie das zu überwindende Drehmoment, welches am Rotor (11) der Vorrichtung zur Speiserestzerkleinerung (10) anliegt, ermitteln und selbigen Rotor (11) dazu veranlassen, seine Drehrichtung umzukehren, wenn festgestellt wird, dass das zu überwindende Drehmoment einen vorher festgelegten Schwellwert überschreitet.

2. Geschirrspülmaschine gemäß Anspruch 1, dadurch gekennzeichnet, dass besagte Sensormittel (19) einen SchwellwertKomparator enthalten, der mittels eines Signals angesteuert wird, welches Informationen über das besagte zu überwindende Drehmoment enthält wie beispielsweise den von besagtem Elektromotor (18) aufgenommenen Strom, die Phasendifferenz zwischen der Spannung und dem Strom dieses Motors (18) oder dergleichen.

3. Geschirrspülmaschine gemäß Anspruch 1, dadurch gekennzeichnet, dass der Rotor (11) der besagten Vorrichtung zur Speiserestzerkleinerung (10) normalerweise durch den besagten Motor (18) dergestalt angetrieben wird, dass er seine Drehrichtung zyklisch umkehrt.

4. Geschirrspülmaschine gemäß Anspruch 1, welches ein Filtersystem (7, 9, 17) umfasst, das im Strömungsweg des von einer Umwälzpumpe (4) in Umlauf gesetzten Spülwassers angeordnet ist, dadurch gekennzeichnet, dass mindestens ein Hauptbereich (9) des besagten Filtersystems (7, 9, 17) dergestalt ausgelegt ist, dass es gemeinsam mit dem Rotor (11) der Vorrichtung zur Speiserestzerkleinerung (10) in Drehung versetzt wird und mit mindestens einer Düse (21) oder dergleichen verbunden ist, welche dergestalt ausgelegt ist, dass sie von der besagten Umwälzpumpe (4) dergestalt gespeist wird, dass sie einen Gegenstrom von Wasser abgibt, der in der Lage ist, den besagten Bereich (9) des besagten Filtersystems zu bespülen und zu reinigen.

5. Geschirrspülmaschine gemäß Anspruch 4, dadurch gekennzeichnet, dass die besagte Düse (21 ) mit der Austragseite (5) der Umwälzpumpe (4) über eine Zweigleitung (22) mit Messblende angeschlossen ist.

6. Geschirrspülmaschine gemäß Anspruch 4, dadurch gekennzeichnet, dass der besagte Hauptbereich (9) des Filtersystems in seiner Gestalt im Wesentlichen kegelstumpfförmig oder zylindrisch ist und auf drehbare Weise mit besagtem Rotor (11) der besagten Vorrichtung zur Speiserestzerkleinerung (10) dergestalt verbunden ist, dass er imstande ist, sich um seine eigene Hauptachse, die fest damit verbunden ist, zu drehen.

7. Geschirrspülmaschine gemäß Anspruch 4, dadurch gekennzeichnet, dass die besagte Vorrichtung zur Speiserestzerkleinerung (10) mindestens eine Wand aufweist, welche im Wesentlichen durch einen Hilfsfilter (17) festgelegt ist, welcher im Wesentlichen vom besagten Hauptfilter (9) umgeben ist.

8. Geschirrspülmaschine gemäß Anspruch 1 , dadurch gekennzeichnet, dass die besagte Abflussleitung (15) in Strömungsrichtung hinter einer Ablasspumpe (16) normalerweise nicht in Betrieb befindliche Strömungsverteilungsmittel (24) enthält, welche so ausgelegt sind, dass sie während einer zeitweiligen Phase wahlweise die Austragsseite der besagten Ablasspumpe (16) mit einer Rückflussleitung (23), welche mit dem Inneren des Waschbehälters (1) in Verbindung steht, auf eine derartige Weise verbinden, dass eine geschlossene Schleife des durch die besagte Zerkleinerungsvorrichtung (10) hindurchtretenden Wasserkreislaufes für die Schmutzteilchen zustande kommt, die durch einen Wasserstrom transportiert werden, der von der besagten Ablasspumpe (16) erzeugt wird.

9. Geschirrspülmaschine gemäß Anspruch 8, dadurch gekennzeichnet, dass das nach Abschluss der besagten zeitweiligen Phase die Ablasspumpe (16) zeitweilig betrieben wird, um durch das besagte Verteilermittel (24) Wasser abzulassen, welches die Schmutzteilchen enthält, die vorher durch die besagte Vorrichtung zur Zerkleinerung von Speiseresten (10) aufs Feinste zerkleinert worden sind.

Revendications

1. Lave-vaisselle comportant un dispositif de broyage de déchets encastré (10) incorporé dans celui-ci qui a une entrée en communication avec la cuve de lavage (1) de la machine et une sortie (14) reliée à une conduite de sortie (15), ledit dispositif de broyage de déchets (10) comportant à son tour un rotor (11) adapté pour tourner de manière sélective dans les deux sens opposés, caractérisé en ce que ledit rotor (11) est entraîné par un moteur électrique bidirectionnel (18), qui est commandé par des moyens formant capteur (19) adaptés pour détecter le couple résistant appliqué au rotor (11) du dispositif de broyage de déchets (10) et pour amener le susdit rotor (11) à inverser son sens de rotation lorsque l'on détecte que le couple résistant dépasse une valeur de seuil prédéterminée.

2. Lave-vaisselle selon la revendication 1, caractérisé en ce que lesdits moyens formant capteur (19) comportent un comparateur de valeurs de seuil commandé par un signal qui est indicatif dudit couple résistant, tel que le courant absorbé par ledit moteur électrique (18), la différence de phase entre la tension et le courant du susdit moteur (18), ou analogue.

3. Lave-vaisselle selon la revendication 1, caractérisé en ce que le rotor (11) dudit dispositif de broyage de déchets (10) est normalement entraîné par ledit moteur (18) afin d'inverser son sens de rotation de manière cyclique.

4. Lave-vaisselle selon la revendication 1, comportant un système de filtrage (7, 9, 17) agencé dans le trajet d'écoulement de l'eau de lavage mise en circulation par une pompe de circulation (4), caractérisé en ce qu'au moins une partie principale (9) dudit système de filtrage (7, 9, 17) est adaptée pour être conjointement entraînée de manière rotative avec le rotor (11) du dispositif de broyage de déchets (10) et est associée à au moins un gicleur (21) ou analogue, adapté pour être alimenté par ladite pompe de circulation (4) afin de produire un jet d'eau à contre-courant capable de rincer et de nettoyer ladite partie (9) dudit système de filtrage.

5. Lave-vaisselle selon la revendication 4, caractérisé en ce que ledit gicleur (21) est relié au côté refoulement (5) de la pompe de circulation (4) par un tuyau d'embranchement à alésage calibré (22).

6. Lave-vaisselle selon la revendication 4, caractérisé en ce que ladite partie principale (9) du système de filtrage a une forme sensiblement tronconique ou cylindrique et est reliée de manière rotative audit rotor (11) dudit dispositif de broyage de déchets (10) afin de pouvoir tourner autour de son propre axe principal, en formant un seul bloc avec celui-ci.

7. Lave-vaisselle selon la revendication 4, caractérisé en ce que ledit dispositif de broyage de déchets (10) a au moins une paroi qui est sensiblement définie par un filtre auxiliaire (17), qui est sensiblement entouré par ledit filtre principal (9).

8. Lave-vaisselle selon la revendication 1, caractérisé en ce que ladite conduite de sortie (15) comporte, en aval d'une pompe de vidange (16), des moyens de déviation d'écoulement normalement inopérants (24) adaptés pour relier de manière sélective, pendant une phase temporaire, le côté refoulement de ladite pompe de vidange (16) à un tuyau de retour (23) communiquant avec l'intérieur de la cuve de lavage (1), de manière à créer un circuit de transport d'eau en boucle fermée, passant à travers ledit dispositif de broyage de déchets (10), pour les particules de déchets transportées par un écoulement d'eau généré par ladite pompe de vidange (16).

9. Lave-vaisselle selon la revendication 8, caractérisé en ce que, à la fin de ladite phase temporaire, la pompe de vidange (16) est temporairement actionnée pour évacuer, par l'intermédiaire desdits moyens de déviation (24), l'eau contenant les particules de déchets qui ont été précédemment broyées le plus finement par ledit dispositif de broyage de déchets (10).

Drawing