WATER-USING DOMESTIC APPLIANCE AND METHOD FOR OPERATING A WATER-USING DOMESTIC APPLIANCE

Abstract

A water-using household appliance includes an electrically controllable actuator, a first voltage source designed to provide a switch-on power amount to the actuator, a second voltage source designed to provide a holding power amount to the actuator, and a control unit designed to electrically connect the first voltage source to the actuator in order to switch on the actuator and, after a switch-on interval, to electrically disconnect the first voltage source from the actuator and to electrically connect the second voltage source to the actuator.

Claims

1-15. (canceled)

16. A water-using household appliance, in particular dishwasher, comprising: an electrically controllable actuator; a first voltage source designed to provide a switch-on power amount to the actuator; a second voltage source designed to provide a holding power amount to the actuator; and a control unit designed to electrically connect the first voltage source to the actuator in order to switch on the actuator and, after a switch-on interval, to electrically disconnect the first voltage source from the actuator and to electrically connect the second voltage source to the actuator.

17. The water-using household appliance of claim 16, wherein the actuator consumes a switch-on power amount which is greater than 50% of a maximum output power of the first voltage source.

18. The water-using household appliance of claim 16, further comprising a plurality of said electrically controllable actuator, said first voltage source being designed to provide the switch-on power amount for each individual actuator of the plurality of said electrically controllable actuator, and said second voltage source being designed to provide simultaneously the holding power amount for at least two actuators of the plurality of said electrically controllable actuator, wherein the control unit is designed to switch on at least two actuators of the plurality of said electrically controllable actuator in order to connect the first voltage source electrically to a first one of the at least two actuators, and after the switch-on interval of the first one of the at least two actuators to disconnect the first voltage source electrically from the first one of the at least two actuators and to connect the second voltage source electrically to the first one of the at least two actuators, and to connect the first voltage source electrically to a further one the at least two actuators of the plurality of said electrically controllable actuator, and after the switch-on interval of the further one the at least two actuators to disconnect the first voltage source electrically from the further one the at least two actuators and to connect the second voltage source electrically to the further one the at least two actuators.

19. The water-using household appliance of claim 16, further comprising a plurality of said second voltage source and a plurality of said electrically controllable actuator, with the second voltage sources of the plurality of plurality of said second voltage source being operably connected to the actuators of the plurality of said electrically controllable actuator in one-to-one correspondence and designed to provide the holding power amount for the actuators of the plurality of said electrically controllable actuator, respectively.

20. The water-using household appliance of claim 16, wherein at least one of the first voltage source and the second voltage source has a maximum output power of 15 W.

21. The water-using household appliance of claim 16, wherein the first voltage source has a constant output voltage of up to 48 V, preferably up to 24 V, further preferably up to 12 V, and wherein the second voltage source has a constant output voltage of up to 48 V, preferably up to 24 V, further preferably up to 12 V.

22. The water-using household appliance of claim 16, wherein the first voltage source has an output voltage which is higher, in particular at least twice as high, as the second voltage source.

23. The water-using household appliance of claim 16, wherein the first voltage source has an output voltage which is at least twice as high as the second voltage source.

24. The water-using household appliance of claim 16, wherein the actuator has a holding voltage which is at most 70%, preferably at most 50%, further preferably at most 35%, further preferably at most 25%, of a switch-on voltage of the actuator.

25. The water-using household appliance of claim 16, wherein the holding power amount provided by the second voltage source to the actuator is at most 70% of the switch-on power amount provided by the first voltage source to the actuator.

26. The water-using household appliance of claim 16, wherein the holding power amount provided by the second voltage source to the actuator is at most 50% of the switch-on power amount provided by the first voltage source to the actuator.

27. The water-using household appliance of claim 16, wherein the holding power amount provided by the second voltage source to the actuator is at most 35% of the switch-on power amount provided by the first voltage source to the actuator.

28. The water-using household appliance of claim 16, wherein the holding power amount provided by the second voltage source to the actuator is at most 25% of the switch-on power amount provided by the first voltage source to the actuator.

29. The water-using household appliance of claim 16, wherein the control unit is designed to switch over from the first voltage source to the second voltage source within a switchover time which is shorter than a switch-off time of the actuator.

30. The water-using household appliance of claim 16, wherein the control unit is designed to switch over from the first voltage source to the second voltage source such that during a switchover interval the first voltage source and the second voltage source are connected simultaneously to the actuator.

31. The water-using household appliance of claim 16, further comprising a diode arranged in an electrical connection between the second voltage source and the actuator such that a current flow from the first voltage source to the second voltage source is prevented.

32. The water-using household appliance of claim 16, wherein the actuator comprises an electromagnetic actuator and/or a thermoelectric actuator.

33. A method for operating a water-using household appliance, in particular a dishwasher, said method comprising: connecting an electrically controllable actuator of the water-using household appliance to a first voltage source for providing a switch-on power amount in order to switch on the actuator; disconnecting the first voltage source from the actuator after elapse of a switch-on interval; and connecting the actuator to a second voltage source for providing a holding power amount in order to keep the actuator switched on.

34. The method of claim 39, further comprising: connecting the first voltage source to a further actuator of the water-using household appliance after the first voltage source has been disconnected from the actuator, in order to switch on the further actuator; disconnecting the first voltage source from the further actuator after elapse of a switch-on interval; and connecting the further actuator to the second voltage source in order to keep the actuator switched on. connecting the further actuator (20) to the second voltage source (40) in order to keep the actuator (20) switched on.

Description

[0059] Further advantageous embodiments and aspects of the invention form the subject matter of the subclaims and the exemplary embodiments of the invention described hereinafter. The invention is also described in more detail using preferred embodiments, with reference to the accompanying figures.

[0060] FIG. 1 shows a schematic perspective view of an exemplary embodiment of a water-using household appliance;

[0061] FIG. 2 shows a schematic block diagram of an exemplary embodiment of an electrical circuit;

[0062] FIG. 3A shows an exemplary diagram of a power output of the first and second voltage source;

[0063] FIG. 3B shows a further exemplary diagram of a power output of the first and second voltage source; and

[0064] FIG. 4 shows a schematic block diagram of a method for operating a water-using household appliance.

[0065] Elements which are the same or functionally the same are provided in the figures with the same reference characters unless indicated otherwise.

[0066] FIG. 1 shows a schematic perspective view of an embodiment of a water-using household appliance 1 which is configured in this case as a household dishwasher. The household dishwasher 1 comprises a washing container 2 which is able to be closed by a door 3, in particular in a water-tight manner. To this end, a sealing device may be provided between the door 3 and the washing container 2. The washing container 2 is preferably cuboidal. The washing container 2 may be arranged in a housing of the household dishwasher 1. The washing container 2 and the door 3 may form a washing chamber 4 for washing the items to be washed.

[0067] The door 3 is shown in FIG. 1 in the open position thereof. The door 3 may be closed or opened by pivoting about a pivot axis 5 provided at a lower end of the door 3. A loading opening 6 of the washing container 2 may be closed or opened by means of the door 3. The washing container 2 has a bottom 7, a ceiling 8 arranged opposite the bottom 7, a rear wall 9 arranged opposite the closed door 3, and two side walls 10, 11 arranged opposite one another. The bottom 7, the ceiling 8, the rear wall 9 and the side walls 10, 11 may be produced, for example, from a stainless steel sheet. Alternatively, for example, the bottom 7 may be produced from a plastics material.

[0068] The household dishwasher 1 also has at least one receptacle for items to be washed 12 to 14. Preferably, a plurality of receptacles for items to be washed 12 to 14, for example three thereof, may be provided, wherein the receptacle for items to be washed 12 has a lower receptacle for items to be washed or a bottom basket, the receptacle for items to be washed 13 has an upper receptacle for items to be washed or a top basket and the receptacle for items to be washed 14 has a cutlery tray. As FIG. 1 also shows, the receptacles for items to be washed 12 to 14 are arranged one above the other in the washing container 2. Each receptacle for items to be washed 12 to 14 is selectively displaceable into the washing container 2 or out of said washing container. In particular, each receptacle for items to be washed 12 to 14 is able to be pushed or retracted into the washing container 2 in a push-in direction E and is able to be pulled or extended out of the washing container 2 counter to the push-in direction E in a pull-out direction A.

[0069] The household dishwasher 1 also has on the door 3 an electrically controllable actuator 20 which is configured, for example, in this case as an electric motor for an electrical automatic door closing system. The electric motor 20 is designed for operation at 12 V DC voltage. A first voltage source 30 and a second voltage source 40 are provided. The first voltage source 30 and the second voltage source 40 are configured such that the maximum output power thereof is under 15 W. The first voltage source 30 in this case has an output voltage of 24 V DC voltage, the second voltage source 40 has an output voltage of 12 V DC voltage. The voltage sources 30, 40 are connected to a public power grid, not shown, which provides for example a 230 V AC voltage at 50 Hz.

[0070] A control unit 50 switches the voltage sources 30, 40 to the electric motor 20. For switching on the electric motor 20, for example in order to bring about a closing of the door 3, the control unit 50 initially switches the first voltage source 30 to the electric motor 20. This provides a switch-on power amount PE which is provided in this case at a voltage of 24 V. With the higher voltage of 24 V the electric motor 20 responds rapidly and has a high starting torque. Thus the electric motor 20 rapidly reaches a stable operating state. As soon as the electric motor 20 is in the stable operating state, for example when it has reached a specific speed, the control unit 50 switches over from the first voltage source 30 to the second voltage source 40. This switchover takes place in a time period during which the electric motor 20 still continues to rotate due to its inertia, for example, although electrical power is no longer supplied to the electric motor. After the switchover, the second voltage source 40 is connected to the electric motor 20 and provides a holding power amount PH thereto, which is provided in the present case at a voltage of 12 V. At 12 V the electric motor 20 consumes less electrical energy and still remains in a stable operating state. When the door 3 is closed, the control unit 50 disconnects the second voltage source 40 from the electric motor 20, whereby this electric motor is switched off.

[0071] FIG. 2 shows a schematic block diagram of an exemplary embodiment of an electrical circuit, according to which the voltage sources 30, 40 are connected, for example, to the electric motor 20 of the automatic door closing system according to FIG. 1. The voltage sources 30, 40 may be connected in each case to the actuator 20 by means of a switch 52 which is controlled by the control unit 50. As a particularity, a diode 35 is arranged in the connection of the second voltage source 40 to the actuator 20. When both switches 52 are closed at one point in time, this diode 35 prevents a current from flowing from the first voltage source 30 into the second voltage source 40. This may occur, in particular, when the first voltage source 30 provides a higher voltage than the second voltage source 40. Different variants of a switchover by the control unit 50 are shown in the following figures FIG. 3A and 3B.

[0072] FIG. 3A shows an exemplary diagram of a power output of the first and second voltage source 30, 40 (see FIG. 1 or 2). In this example, two actuators 20 (see FIG. 1 or 2) are switched on one after the other and operated at the same time for a specific time interval. For example, the actuators 20 are a circulating pump and a drain pump of a household dishwasher. The diagram shows on the horizontal axis t a time coordinate and on the vertical axis P a power which is output in each case from the first voltage source 30 (solid line) and the second voltage source 40 (dashed line).

[0073] Initially the two pumps are switched off, which is why the two voltage sources 30, 40 do not output any power. At a time t0 the circulating pump is initially switched on. Thus the first voltage source 30 provides the switch-on power amount PE to the circulating pump. This switch-on power amount is provided, for example, at 48 V. After the elapse of a switch-on interval, at the time t1, the circulating pump is in a stable operating state. Now the first voltage source 30 is disconnected from the pump which is why the power drops back to 0. After a brief moment, at the time t2, the second voltage source 40 is connected to the pump and henceforth provides the holding power amount PH. The second voltage source outputs a 12 V voltage signal. The holding power amount PH is only approximately 25% of the switch-on power amount PE, which is why an energy-saving continuous operation of the circulating pump is possible.

[0074] At a later time t3, the lye pump is switched on by the first voltage source 30 being connected thereto. After the lye pump has reached a stable operating state at a time t4, initially the first voltage source 30 is disconnected from the lye pump and immediately afterwards, at the time t5, the second voltage source 40 is connected to the lye pump. Now the second voltage source 40 supplies both the circulating pump and the lye pump with electrical power. The output power corresponds to approximately twice the holding power amount PH. At a time t6 the circulating pump is switched off, i.e. the second voltage source 40 is disconnected from the circulating pump, which is why the output power drops again to a holding power amount PH. It should be mentioned that different actuators 20 may have different switch-on power amounts PE and/or holding power amounts PH, even if this is not shown here.

[0075] FIG. 3B shows a further exemplary diagram of a power output of the first and second voltage source 30, 40. In FIG. 3B only one switch-on process is shown with the subsequent switchover. The difference from the two switch-on processes shown in FIG. 3A with the subsequent switchover is that here the second voltage source 40 is already connected at the time t1 to the actuator 20, whilst the first voltage source 30 is still connected to the actuator 20. The first voltage source 30 is only disconnected from the actuator 20 at a time t2. In the time interval dt=(t2−t1) both voltage sources 30, 40 are thus connected to the actuator 20. This is expedient, in particular in the case of actuators 20 which may react very sensitively to voltage fluctuations, in order to ensure that these actuators are not transferred into the switched-off state during the switchover.

[0076] FIGS. 3A and 3B show diagrams which refer to the power of the voltage sources 30, 40. It should be mentioned that if the connected actuator 20 has an ohmic behavior, the curves shown may be achieved by a corresponding output voltage.

[0077] FIG. 4 shows a schematic block diagram of an exemplary method for operating a water-using household appliance 1, for example the household dishwasher of FIG. 1. In a first step S1 an actuator 20 (see FIG. 1 or 2) is electrically connected to a first voltage source 30 (see FIG. 1 or 2) for providing a switch-on power amount PE (see FIG. 3A or 3B) in order to switch on the actuator 20. In a second step S2 the first voltage source 20 is disconnected from the actuator 20 after the elapse of a switch-on interval. In a third step S3 the actuator 20 is connected electrically to a second voltage source 40 (see FIG. 1 or 2) for providing a holding power amount PH (see FIG. 3A or 3B).

[0078] In embodiments of the method, the third step S3 may take place before the second step S2. Moreover, this method may be repeated multiple times in order to switch on a plurality of actuators 20 one after the other and to operate said actuators by the second voltage source 40.

[0079] Although the present invention has been described using exemplary embodiments, it may be modified in many different ways.

REFERENCE CHARACTERS USED

[0080] 1 Water-using household appliance [0081] 2 Washing container [0082] 3 Door [0083] 4 Washing chamber [0084] 5 Pivot axis [0085] 6 Loading opening [0086] 7 Bottom [0087] 8 Ceiling [0088] 9 Rear wall [0089] 10 Side wall [0090] 11 Side wall [0091] 12 Receptacle for items to be washed [0092] 13 Receptacle for items to be washed [0093] 14 Receptacle for items to be washed [0094] 20 Actuator [0095] 30 Voltage source [0096] 35 Diode [0097] 40 Voltage source [0098] 50 Control unit [0099] 52 Switch [0100] A Pull-out direction [0101] E Push-in direction [0102] GND Neutral-potential [0103] P Power [0104] PE Switch-on power amount [0105] PH Holding power amount [0106] S1 Method step [0107] S2 Method step [0108] S3 Method step [0109] t Time axis [0110] t0 Time [0111] t1 Time [0112] t2 Time [0113] t3 Time [0114] t4 Time [0115] t5 Time [0116] t6 Time