HOUSEHOLD DISHWASHER

Description

[0001] The present invention relates to a household dishwasher.

[0002] A dishwasher comprises a wash tub in which items to be cleaned can be accommodated. A rotating spray arm can be provided within the wash tub to apply wash liquor and / or fresh water to the items to be washed. This spray arm can be driven either by the pressure of wash liquor and / or fresh water escaping from the spray arm's spray nozzles or by an active drive, in particular an electric motor. If an active drive is provided, a blockage of the spray arm can lead to the drive being overloaded. Furthermore, when handling the spray arm or when handling items in the wash tub, a force can be applied to the spray arm, which can also lead to overloading. Both of these must be prevented.

[0003] US 2011 / 0146733 A1 describes a spray device for a dishwasher that is motorized by means of a drive system. The drive system includes a magnetic coupling. The magnetic coupling comprises a first part located inside a wash chamber of the dishwasher and a second part located outside the wash chamber, so that a motor and an output shaft of the drive system are located entirely outside the wash chamber.

[0004] DE 10 2009 042 867 A1 discloses a dishwasher with one or more washing areas in which at least one rotatable wash arm is arranged. The dishwasher comprises a drive device for driving a rotatable wash arm, wherein the drive device comprises at least one device for generating a variable magnetic field for driving at least one wash arm.

[0005] Against this background, it is an object of the present invention to provide an improved household dishwasher.

[0006] Accordingly, a household dishwasher is proposed comprising a wash tub, a spray arm for applying wash liquor and / or fresh water to the washware held in the wash tub, a drive device for actively driving the spray arm, and an overload protection device. In the event of a spray arm blockage, the overload protection device automatically switches from a coupled state, in which power transmission is present between the drive device and the spray arm, to a decoupled state, in which power transmission between the drive device and the spray arm is interrupted. The overload protection device is spring-loaded toward the coupled state.

[0007] The overload protection reliably prevents the drive system from being overloaded. This prevents, in particular, damage to a drive element of the drive system or to its gear unit.

[0008] The washing compartment is preferably cuboid-shaped. In particular, the washing compartment comprises a base, a ceiling arranged opposite the base, a door, a rear wall arranged opposite the closed door, and two side walls. Dishware receptacles for holding the dishes can be provided in the washing compartment. For example, an upper basket, a lower basket, and a cutlery drawer are provided. The spray arm can be arranged below the lower basket. The spray arm can, in particular, be rotatably mounted on the base. Alternatively, the spray arm can also be arranged between the lower basket and the upper basket.

[0009] In this context, "exposure" to the washware with wash liquor and / or fresh water means that the washware is wetted with wash liquor and / or fresh water using the spray arm. "Wash liquor" can be understood to mean water mixed with a cleaning agent. The wash liquor can include soils detached from the washware. "Actively driven" of the spray arm means that the drive device applies torque to the spray arm. "Active" driving, in this context, therefore does not mean that the spray arm is rotated using spray nozzles. To actively drive a spray arm, the drive device comprises a drive element, in particular an electric motor, which rotates a drive shaft.

[0010] The spray arm comprises, in particular, an actively driven extension arm and a spray arm satellite rotatably mounted on the extension arm. The spray arm satellite is preferably not actively driven, but is driven by wash liquor and / or fresh water flowing from the spray nozzles thereof. A "blockage" of the spray arm is understood here to mean, in particular, a blockage of the aforementioned extension arm. "Blockage" can be understood to mean a blockage caused by washware but also by an external force, for example, by a user. The fact that the overload protection device "independently" moves from the coupled state to the uncoupled state and back again is understood, in particular, to mean that the overload protection device can be moved from the coupled state to the uncoupled state and vice versa without an active drive element and / or sensors.As previously mentioned, the drive device preferably comprises the drive element and a plurality of gears driven by the drive element. One of the gears is operatively connected to the spray arm, in particular to the extension arm of the spray arm. For this purpose, the extension arm can have a spray arm toothing into which one of the gears positively engages.

[0011] The overload protection device is spring-loaded in the direction of the coupling state.

[0012] This specifically means that the overload protection device automatically switches from the uncoupled state to the coupled state. Conversely, this means that the overload protection device can only be switched from the coupled state to the uncoupled state against the spring force of a spring element. The spring element, in turn, switches the overload protection device from the uncoupled state back to the coupled state without any external force.

[0013] According to a further embodiment, an axis of rotation of a drive shaft of the drive device and an axis of rotation of the spray arm are arranged parallel to each other and spaced apart from each other.

[0014] In this case, the fact that the rotational axis of the spray arm and the rotational axis of the drive shaft are arranged "spaced apart" means, in particular, that the two rotational axes are arranged a certain distance apart. This means that the rotational axis of the drive shaft and the rotational axis of the spray arm do not coincide with each other. The rotational axis of the spray arm is identical to a rotational axis of the boom. This means, in particular, that the rotational axis of the drive shaft and the rotational axis of the boom are arranged parallel to each other and spaced apart from each other.

[0015] According to a further embodiment, the overload protection device is accommodated in a gear wheel of the drive device.

[0016] This allows for a particularly compact design. To accommodate the overload protection device within the gear, the gear is preferably hollow and has a receiving area for accommodating the overload protection device.

[0017] According to a further embodiment, the overload protection device comprises an overload element which is in force-locking and / or form-locking engagement with a counter-engagement section of the gear for the transmission of force between the drive device and the spray arm, wherein the overload element is disengaged from force-locking and / or form-locking engagement with the counter-engagement section in the event of a blockage of the spray arm in order to move the overload protection device from the coupling state to the uncoupling state.

[0018] A positive connection is created by the interlocking or engaging of at least two connecting partners. A non-positive connection requires a normal force on the surfaces to be connected. Non-positive connections can be realized by frictional engagement. The mutual displacement of the surfaces is prevented as long as the counterforce caused by static friction is not exceeded. The counter-engagement section and the overload element have corresponding control surfaces that can slide against each other with friction. The engagement of the overload element in or with the counter-engagement section can be purely non-positive, purely positive, or both non-positive and positive. The overload element preferably comprises an engagement section with the aforementioned control surfaces, wherein the engagement section can engage with the counter-engagement section.The counter-engagement section has control surfaces corresponding to the control surfaces of the engagement section.

[0019] According to a further embodiment, when the spray arm is blocked, the overload element moves linearly along a rotational axis of the gear in order to move the overload protection device from the coupling state to the decoupling state.

[0020] The rotational axis of the gear preferably corresponds to the aforementioned rotational axis of the drive shaft of the drive element of the drive device. When the overload protection device is moved from the uncoupled state to the coupled state, the overload element also moves linearly along the rotational axis.

[0021] According to a further embodiment, the overload protection device comprises a housing element which is connected to the overload element, wherein a spring element is arranged between the overload element and the housing element.

[0022] The spring element is, in particular, a cylindrical spring. Preferably, the spring element is a compression spring. The housing element and the overload element are preferably cup-shaped. The housing element can be accommodated at least partially in the overload element. The housing element is preferably positively connected to the overload element. For this purpose, locking hooks or snap hooks can be provided.

[0023] According to a further embodiment, the spring element moves the overload element linearly relative to the housing element along the axis of rotation of the gear when the overload protection device is moved from the coupling state to the decoupling state.

[0024] For this purpose, appropriate guides, for example in the form of grooves and ribs, can be provided on the overload element and on the housing element.

[0025] According to a further embodiment, the spring element is accommodated at least in sections in the overload element.

[0026] The spring element can also be accommodated at least in sections in the housing element.

[0027] According to a further embodiment, when the spray arm is blocked, the overload element moves linearly perpendicular to a rotational axis of the gear in order to move the overload protection device from the coupling state to the decoupling state.

[0028] As previously mentioned, the rotational axis of the gear is preferably identical to the rotational axis of the drive shaft of the drive element of the drive device. The vertical movement along the rotational axis allows for a particularly compact design of the overload protection device.

[0029] According to a further embodiment, the overload protection device comprises a housing element received in the gear wheel, wherein a spring element is arranged between the housing element and the overload element.

[0030] Preferably, the housing element is cylindrical. The housing element is accommodated in the gear. The overload element, in turn, is accommodated in the housing element.

[0031] According to a further embodiment, the spring element moves the overload element linearly relative to the housing element when the overload protection device is moved from the coupling state to the decoupling state perpendicular to the axis of rotation of the gear.

[0032] Preferably, a receiving section is provided in the housing element, in which the overload element is accommodated. Furthermore, a guide section is provided, in which a guide pin of the overload element is linearly guided. This prevents the overload element from tilting.

[0033] According to a further embodiment, the overload element is accommodated at least in sections in the spring element.

[0034] In particular, the spring element is accommodated in the housing element. Preferably, a base section, in particular a cylindrical section, of the overload element is accommodated in the spring element.

[0035] According to a further embodiment, the household dishwasher further comprises a detection device with the aid of which it can be detected whether the overload protection device is in the coupling state or in the uncoupling state.

[0036] This makes it possible to inform the user whether the overload protection device has been triggered or not. Moving from the coupled state to the uncoupled state can be described as "triggering" the overload protection device. The user can take appropriate measures, for example, removing the blocked items.

[0037] According to a further embodiment, the detection device detects a motor current of the drive device.

[0038] In particular, the detection device detects an increase in the motor current that occurs when the overload protection device is triggered, i.e., when the overload protection device moves from the coupled state to the uncoupled state. For example, after a detected number of increases in the motor current, for example, five, the information can be output that the spray arm is blocked and that action, such as removing the blocked items, must be taken.

[0039] Further possible implementations of the household dishwasher also include combinations of features or embodiments described above or below with regard to the exemplary embodiments that are not explicitly mentioned. In this case, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the household dishwasher.

[0040] Further advantageous configurations and aspects of the household dishwasher are the subject of the dependent claims and the exemplary embodiments of the household dishwasher described below. The household dishwasher is explained in more detail below using preferred embodiments with reference to the accompanying figures. Fig. 1 shows a schematic perspective view of an embodiment of a household dishwasher; Fig. 2 shows a schematic sectional view of an embodiment of a spray device for the household dishwasher according to Fig. 1 ; Fig. 3 shows a schematic sectional view of an embodiment of a drive device for the spray device according to Fig. 2 ; Fig. 4 shows a schematic perspective view of an embodiment of an overload protection device for the drive device according to Fig. 3 ; Fig. 5 shows a schematic perspective sectional view of the overload protection device according to Fig. 4 ; Fig. 6 shows a further schematic perspective sectional view of the overload protection device according to Fig. 4 ; Fig. 7 shows a schematic detailed view of the overload protection according to Fig. 4 ; Fig. 8 shows a schematic sectional view of a further embodiment of a drive device for the spray device according to Fig. 2 ; Fig. 9 shows a schematic plan view of an embodiment of an overload protection device for the drive device according to Fig. 8 ; Fig. 10 shows a further schematic view of the overload protection according to Fig. 9 ; Fig. 11 shows a further schematic view of the overload protection according to Fig. 9 ; Fig. 12 shows the detailed view XII according to Fig. 9 ; and Fig. 13 shows a schematic diagram in which the motor current of the drive device is calculated according to the Fig. 3 and Fig. 8 plotted over time.

[0041] In the figures, identical or functionally equivalent elements have been given the same reference numerals unless otherwise stated.

[0042] The Fig. 1 shows a schematic perspective view of an embodiment of a household dishwasher 1. The household dishwasher 1 comprises a washing container 2, which can be closed by a door 3, in particular in a watertight manner. For this purpose, a sealing device can be provided between the door 3 and the washing container 2. The washing container 2 is preferably cuboid-shaped. The washing container 2 can be arranged in a housing of the household dishwasher 1. The washing container 2 and the door 3 can form a washing chamber 4 for washing dishes.

[0043] Door 3 is in the Fig. 1 shown in its open position. The door 3 can be closed or opened by pivoting about a pivot axis 5 provided at a lower end of the door 3. With the help of the door 3, a loading opening 6 of the washing container 2 can be closed or opened. The washing container 2 has a base 7, a ceiling 8 arranged opposite the base 7, a rear wall 9 arranged opposite the closed door 3 and two side walls 10, 11 arranged opposite one another. The base 7, the ceiling 8, the rear wall 9 and the side walls 10, 11 can be made, for example, from a stainless steel sheet. Alternatively, the base 7 can, for example, be made from a plastic material.

[0044] The household dishwasher 1 further comprises at least one dishware receptacle 12 to 14. Preferably, several, for example three, dishware receptacles 12 to 14 can be provided, wherein the dishware receptacle 12 can be a lower dishware receptacle or a lower basket, the dishware receptacle 13 can be an upper dishware receptacle or an upper basket, and the dishware receptacle 14 can be a cutlery drawer. Fig. 1 As further shown, the dishware receptacles 12 to 14 are arranged one above the other in the washing container 2. Each dishware receptacle 12 to 14 can be selectively moved into or out of the washing container 2. In particular, each dishware receptacle 12 to 14 can be pushed or moved into the washing container 2 in an insertion direction E and pulled or moved out of the washing container 2 in an extension direction A, opposite to the insertion direction E.

[0045] The household dishwasher 1 further comprises a detection device 15. With the aid of the detection device 15, a motor current of a drive device of the household dishwasher 1 can be detected. The detection device 15 can be part of a control unit of the household dishwasher 1. The control unit is suitable for executing a washing program of the household dishwasher 1. For example, a plurality of washing programs can be stored in the control unit. The control unit can, for example, control a circulation pump of the household dishwasher 1. The control unit can be coupled to a display of the household dishwasher 1. With the aid of the display, operating states of the household dishwasher 1 can, for example, be output to a user.

[0046] The Fig. 2 shows a schematic sectional view of an embodiment of a spray device 16 for the household dishwasher 1. The spray device 16 is arranged within the washing compartment 2. In particular, the spray device 16 is positioned below the dishware holder 12. The spray device 16 can be positioned on the floor 7. The spray device 16 comprises a spray arm 17 for applying washing liquor and / or fresh water F to the dishes (not shown) held in the washing compartment 2.

[0047] The spray arm 17 has a boom 18, which is actively driven by a drive device 19, and a spray arm satellite 20 rotatably mounted on the boom 18. The spray arm satellite 20 can have multiple arms. For example, the spray arm satellite 20 can have three arms arranged offset from one another at an angle of 120°. The spray arm satellite 20 comprises multiple spray nozzles. The spray nozzles can be used to spray the washware with wash liquor and / or fresh water F. The spray arm satellite 20 can also comprise drive spray nozzles, with the aid of which the spray arm satellite 20 can be set in rotation.

[0048] The spray arm satellite 20 is mounted on the boom 18 for rotation about a rotation axis 26. The spray arm satellite 20 is not actively driven. This means that the spray arm satellite 20 does not have its own drive device. In particular, the spray arm satellite 20 is recoil-driven by means of the rinsing solution and / or the fresh water F. The drive spray nozzle (not shown) can be provided for this purpose. "Recoil-driven" is understood here to mean that the spray arm satellite 20 is set in rotation about the rotation axis 26 by the rinsing solution and / or the fresh water F emerging from the spray nozzles and / or the drive spray nozzle.

[0049] The boom 18, however, unlike the spray arm satellite 20, is actively driven. The drive device 19 is provided for this purpose. The boom 18 comprises a first arm 27, on which the spray arm satellite 20 is mounted so as to be rotatable about the rotation axis 26, and a second arm 28. The arms 27, 28 can have spray nozzles (not shown). However, the arms 27, 28 can also be free of spray nozzles. Preferably, two such arms 27, 28 are provided. However, the number of arms 27, 28 is arbitrary. Exactly one arm 27, 28 or more than two arms 27, 28 can be provided.

[0050] The boom 18 is rotatable about a rotational axis 29 by means of the drive device 19. The rotational axes 26, 29 are preferably arranged parallel to each other and spaced apart from each other. Both the spray arm satellite 20 and the boom 18 are hollow, so that the rinsing solution and / or the fresh water F can flow through the boom 18 and the spray arm satellite 20 and discharge at the spray nozzles or the drive spray nozzle.

[0051] The drive device 19 comprises a drive element 21, in particular an electric motor, with a drive shaft 35 that rotates about a rotational axis 30 during operation of the household dishwasher 1. The rotational axes 29, 30 are arranged parallel to each other and spaced apart from each other. The drive device 19 is attached to a pump housing 31. The pump housing 31 is attached to the base 7. The extension arm 18 is mounted on the pump housing 31 so as to be rotatable about the rotational axis 29.

[0052] The Fig. 3 shows a schematic sectional view of an embodiment of a drive device 19 as mentioned above. The drive device 19 comprises a gear housing 32 with a lower housing part 33 and an upper housing part 34. The lower housing part 33 and the upper housing part are connected to one another in a form-fitting manner. A form-fitting connection is created by the interlocking or engaging of at least two connecting partners. Latching hooks or snap hooks can be provided on the lower housing part 33 and the upper housing part 34, with the aid of which the lower housing part 33 and the upper housing part 34 can be connected to one another in a form-fitting manner.

[0053] As previously mentioned, the drive device 19 comprises the drive element 21 with the drive shaft 35, which rotates about the rotational axis 30. A plurality of meshing gears 36 to 38 are accommodated in the gear housing 32. Preferably, a first gear 36 is provided, which is rotationally fixedly connected to the drive shaft 35. The rotational axis 30 is simultaneously the rotational axis of the first gear 36. A second gear 37 meshes with the first gear 36. The second gear 37 is rotatably mounted in the gear housing 32 by means of an axle 39. The second gear 37 rotates in the gear housing 32 about a rotational axis 40.

[0054] Engaging with the second gear 37 is a third gear 38, which is rotatably mounted in the gear housing 32 by means of an axle 41. The axles 39, 41 can be bolts or pins mounted in the gear housing 32. The third gear 38 rotates in the gear housing 32 about a rotational axis 42. The third gear 38 is in positive engagement with a spray arm toothing 22 ( Fig. 2 ) of the boom 18 to set it in rotation. An overload protection device 43 is assigned to the first gear 36.

[0055] The Fig. 4 shows a schematic perspective view of an embodiment of an overload protection device 43 as mentioned above for the drive device 19. The Fig. 5 and 6 show schematic perspective sectional views of the overload protection device 43. The Fig. 7 shows a schematic detailed view of the overload protection 43. The following refers to the Fig. 4 bis 7 referred to at the same time.

[0056] In the Fig. 5 and 6 In addition to the overload protection device 43, the first gear 36 is shown. The first gear 36 comprises a cup-shaped base section 44 in which the overload protection device 43 is received. A toothing 45 is provided on the base section 44, which is in positive engagement with the second gear 37. The base section 44 functions as a receiving area for the overload protection device 43.

[0057] The overload protection device 43 comprises an overload element 46 and a housing element 47. A spring element 48 is provided between the overload element 46 and the housing element 47. The spring element 48 can be a cylindrical spring. Preferably, the spring element 48 is a compression spring. The overload element 46 and the housing element 47 are positively connected to one another. For this purpose, snap hooks 49 can be provided on the overload element 46, for example, which can engage in corresponding hook-shaped engagement sections 50 of the housing element 47.

[0058] The housing element 47 comprises a receiving section 51 for receiving the drive shaft 35. In the simplest case, the drive shaft 35 can have a lateral flattening or milled portion, wherein the receiving section 51 has a corresponding geometry, so that the drive shaft 35 is received in the receiving section 51 in a rotationally fixed manner. However, the drive shaft 35 preferably has a multi-tooth profile with a coding. The receiving section 51 is designed accordingly. The housing element 47 further comprises a tubular base section 52, which is connected in one piece, in particular in one piece, to the cylindrical receiving section 51. A plate-shaped bottom section 53 can be provided for this purpose. The spring element 48 is arranged between the base section 52 and the receiving section 51. The spring element 48 is thus at least partially received in the housing element 47.

[0059] The spring element 48 is also accommodated at least partially in the overload element 46. The overload element 46 comprises a cylindrical base section 54, which is closed on the top by a cover section 55. The overload element 46 further comprises an engagement section 56 with two obliquely arranged control surfaces 57, 58. The first gear 36 comprises, on its base section 44, a counter-engagement section 59 corresponding to the engagement section 56, into which the engagement section 56 can engage in a form-fitting manner. The counter-engagement section 59 comprises control surfaces 60 corresponding to the control surfaces 57, 58, of which Fig. 7 only one is shown.

[0060] The functionality of the overload protection device 43 is explained below. If the spray arm 17, and in particular the extension arm 18, is blocked, the drive element 21 continues to rotate the drive shaft 35. To prevent damage to the drive element 21 or the gears 36 to 38, the overload protection device 43 can be activated by a Fig. 5 shown coupling state Z1, in which a force transmission between the drive device 19 and the spray arm 17, in particular the boom 18, is present, into a Fig. 6 The coupling state Z1 can be changed to the decoupling state Z2 shown, in which the power transmission between the drive device 19 and the spray arm 17, in particular the boom 18, is interrupted. Moving the overload protection device 43 from the coupling state Z1 to the decoupling state Z2 can also be referred to as "triggering" the overload protection device 43.

[0061] This transition from the coupling state Z1 to the decoupling state Z2 occurs when the control surfaces 58, 60 slide against each other with friction, causing the overload element 46 to move toward the housing element 47 against a spring preload of the spring element 48. This movement occurs linearly along the rotation axis 30. If the drive shaft 35 continues to rotate, the spring element 48 automatically returns the overload protection device 43 from the decoupling state Z2 to the coupling state Z1. If the spray arm 17, and in particular the boom 18, remains blocked, the overload protection device 43 is moved from the coupling state Z1 to the decoupling state Z2 and back with each rotation of the drive shaft 35.

[0062] As the Fig. 7 shows, a spring force F1 of the spring element 48 acts on the control surfaces 58, 60. A normal force F2 acts perpendicular to the control surfaces 58, 60. A resulting force F3 acts perpendicular to the spring force F1. A frictional force F4 acts parallel to the control surfaces 58, 60. The force ratio of the forces F1 to F4 can be varied by a corresponding selection of the spring element 48, so that the overload protection 43 triggers either earlier or later in the event of a blockage of the spray arm 17, in particular the boom 18.

[0063] The Fig. 8 shows a schematic sectional view of a further embodiment of a drive device 19' for the spray device 16. The drive device 19' comprises, as already described with reference to the drive device 19 according to the Fig. 3 explained, a gear housing 32 with a lower housing part 33 and an upper housing part 34. Three gears 36 to 38, in particular a first gear 36, a second gear 37 and a third gear 38, are accommodated in the gear housing 32.

[0064] The first gear 36 is operatively connected to a drive shaft 35 of a drive element of the drive device 19', as previously mentioned with reference to the drive device 19, and rotates about the rotational axis 30. The second gear 37 is assigned an axis 39. The second gear 37 rotates about an axis of rotation 40. The third gear 38 is assigned an axis 41. The third gear 38 rotates about an axis of rotation 42. The first gear 36 is assigned an overload protection device 43'. The overload protection device 43' basically has the same functionality as the overload protection device 43, which was previously explained. The drive devices 19, 19' differ from one another essentially in the structural design of the respective overload protection devices 43, 43'.

[0065] The Fig. 9 shows a schematic plan view of the overload protection device 43' in a coupling state Z1 as previously explained. Fig. 10 shows a further schematic plan view of the overload protection device 43' in an intermediate state Z3. The Fig. 11 shows a schematic plan view of the overload protection device 43' in a decoupling state Z2 as previously explained. Fig. 12 shows the detailed view XII according to the Fig. 9 . The following refers to the Fig. 9 bis 12 referred to at the same time.

[0066] The first gear 36 comprises - as already explained with reference to the drive device 19 - a toothing 45 which engages with the second gear 37. The first gear 36 comprises an inner contour 61 with a groove-shaped counter-engagement section 62. The counter-engagement section 62 has two control surfaces 63, 64 ( Fig. 12 ). The inner contour 61 is circular in sections, but has two flattened areas 65, 66 of the circular geometry of the inner contour 61 adjacent to the counter-engagement section 62 on both sides. The overload protection device 43' comprises a housing element 67 rotatably received in the first gear 36. Received in the housing element 67 are an overload element 68 and a spring element 69. The overload element 68 is received at least in sections in the spring element 69. The spring element 69 can be a cylindrical spring. In particular, the spring element 69 is a compression spring.

[0067] The housing element 67 comprises a receiving section 70 in which the spring element 69 and the overload element 68 are received. Adjoining the receiving section 70 is a guide section 71, by means of which the overload element 68 is guided linearly in the housing element 67 perpendicular to the rotational axis 30. For this purpose, a guide pin 72 is provided on the overload element 68. The overload element 68 further comprises a base section 73, which is received in the spring element 69. The base section 73 can be cylindrical.

[0068] An engagement section 74 adjoins the base section 73. The engagement section 74 is suitable for engaging the counter-engagement section 62 in order to move the overload protection device 43' into the coupling state Z1. In order to move the overload protection device 43' from the coupling state Z1 into the decoupling state Z2, the engagement section 74 is moved out of positive engagement with the counter-engagement section 62. The engagement section 74 comprises two control surfaces 75, 76 ( Fig. 12 ).

[0069] As the Fig. 12 shows, depending on the direction of rotation of the drive shaft 35 (not shown), a spring force F1 of the spring element 69 acts on one of the control surfaces 75, 76 of the engagement section 74 and one of the control surfaces 63, 64 of the counter-engagement section 62. In the orientation of the Fig. 12 The drive shaft 35 rotates counterclockwise. A normal force F2 acts perpendicular to the control surfaces 63, 75. A resulting force F3 acts perpendicular to the spring force F1. A friction force F4 acts parallel to the control surfaces 63, 75.

[0070] When the spray arm 17, in particular the boom 18, is blocked, the control surfaces 63, 75 slide against each other with friction, so that the engagement section 74, as shown in the Fig. 10 shown, comes out of positive engagement with the counter-engagement section 62. The engagement section 74 then slides on the flattened portion 65 of the inner contour 61. The spring element 69 remains compressed. As soon as the engagement section 74 has slid over the flattened portion 65, it comes into contact with the circular inner contour 61, whereby the spring element 69 is partially relaxed. As a result, the spring force F1 is reduced. After one rotation of the drive shaft 35, the engagement section 74 snaps back into the counter-engagement section 62. As long as the spray arm 17 is blocked, the overload protection device 43' moves from the coupling state Z1 to the decoupling state Z2 and back with each rotation of the drive shaft 35.

[0071] The Fig. 13 shows a schematic diagram in which the motor current I of the drive element of the drive device 19, 19' is plotted on the ordinate axis. Time t is plotted on the abscissa axis. As previously explained, the overload protection device 43, 43' is provided to protect the spray device 16 and / or the drive device 19, 19' from damage. In the event that the washware blocks the boom 18 while a spray arm 17 is rotating, the overload protection device 43, 43' is triggered when a certain force is exceeded. This force is influenced, among other things, by the respective spring element 48, 69. However, the force or torque required to trigger the overload protection device 43, 43' is not only determined by the spring force F1, but also significantly by the respective angle at which the control surfaces 57, 58, 60, 63, 64, 75, 76 are positioned, and thus by the normal force F2.In addition, the force or torque for triggering the overload protection 43, 43' can be influenced by the material selection and thus by the coefficient of sliding friction.

[0072] The drive shaft 35 can then rotate 360°, and the overload protection device 43, 43' automatically returns from the uncoupled state Z2 to the coupled state Z1. As long as the washware continues to block the boom 18, the overload protection device 43, 43' continues to trigger. Since this continuous load could overload the spray device 16 and / or impair the wash result, it is desirable to alert the user to the blockage. This can be done, for example, by monitoring the motor current I of the drive element.

[0073] Each time the overload protection device 43, 43' is triggered, the detection device 15 can detect an increase 77 to 81 of the motor current I. In the Fig. 13Five such elevations 77 to 81 are shown. If they occur regularly, elevations 77 to 81 can be an indicator of a blockage of the boom 18. For example, after five elevations 77 to 81, a permanent blockage of the spray arm 17 can be assumed.

[0074] For further action upon detection of a blockage of the spray arm 17 or the boom 18, for example, the household dishwasher 1 can now be switched off. Optionally, additionally or alternatively, an error message can be displayed to the user. Furthermore, the user could be notified via SmartApp that there is a blockage of the boom 18, which the user can rectify. Furthermore, in the event that the drive device 19, 19' itself is damaged, a message can be issued indicating that customer service must be called. Alternatively, the household dishwasher 1 can continue to run without any external action. However, this could result in poorer cleaning results.

[0075] Although the present invention has been described using exemplary embodiments, it can be modified in many ways. Reference symbols used:

[0076] 1 Household dishwasher 2 Washing container 3 Door 4 Washing chamber 5 Swivel axis 6 Loading opening 7 Floor 8 Ceiling 9 Rear wall 10 Side wall 11 Side wall 12 Dishwasher receptacle 13 Dishwasher receptacle 14 Dishwasher receptacle 15 Detection device 16 Spray device 17 Spray arm 18 Boom 19 Drive device 19 Drive device 20 Spray arm satellite 21 Drive element 22 Spray arm toothing 26 Rotation axis 27 Arm 28 Arm 29 Rotation axis 30 Rotation axis 31 Pump bowl 32 Gear housing 33 Lower housing section 34 Upper housing section 35 Drive shaft 36 Gear 37 Gear 38 Gear 39 Axis 40 Rotation axis 41Axis 42Rotation axis 43Overload protection 43'Overload protection 44Base section 45Toothing 46Overload element 47Housing element 48Spring element 49Snap hook 50Engaging section 51Receiving section 52Base section 53Bottom section 54Base section 55Cover section 56Engaging section 57Control surface 58Control surface 59Counter-engaging section 60Control surface 61Inner contour 62Counter-engaging section 63Control surface 64Control surface 65Flattening66Flat 67Housing element 68Overload element 69Spring element 70Receiving section 71Guide section 72Guide pin 73Base section 74Engaging section 75Control surface 76Control surface 77Elevation 78Elevation 79Elevation 80Elevation 81Elevation AExtension direction EInsertion direction FRinse solution and / or fresh water F1Spring force F2Normal force F3Resulting force F4Friction force IMotor current tTime Z1Coupling state Z2Decoupling state Z3Intermediate state

Claims

1. Household dishwasher (1) with a dishwasher cavity (2), a spray arm (17) for applying washing liquor and / or fresh water (F) to the dishwasher load received in the dishwasher cavity (2), a drive system (19, 19') for actively driving the spray arm (17), and an overload protection mechanism (43, 43'), which, if the spray arm (17) becomes blocked, moves autonomously from a coupling position (Z1), in which power is transmitted between the drive system (19, 19') and the spray arm (17), into a decoupling position (Z2), in which the power transmission between the drive system (19, 19') and the spray arm (17) is interrupted, characterised in that the overload protection mechanism (43, 43') is spring-biased in the direction of the coupling position (Z1).

2. Household dishwasher according to claim 1, characterised in that an axis of rotation (30) of a drive shaft (35) of the drive system (19, 19') and an axis of rotation (26) of the spray arm (17) are arranged parallel to one another and spaced apart from one another.

3. Household dishwasher according to claim 1 or 2, characterised in that the overload protection mechanism (43, 43') is received in a gear wheel (36) of the drive system (19, 19').

4. Household dishwasher according to claim 3, characterised in that the overload protection mechanism (43, 43') comprises an overload element (46, 68), which, for power transmission between the drive system (19, 19') and the spray arm (17), is engaged in a force-fitting manner and / or form-fitting manner with a counter-engagement section (59, 62) of the gear wheel (36), wherein, if the spray arm (17) becomes blocked, the overload element (43, 43') leaves the force-fitting and / or form-fitting engagement with the counter-engagement section (59, 62) in order to move the overload protection mechanism (43, 43') from the coupling position (Z1) into the decoupling position (Z2).

5. Household dishwasher according to claim 4, characterised in that if the spray arm (17) becomes blocked, the overload element (46) moves linearly along an axis of rotation (30) of the gear wheel (36) in order to move the overload protection mechanism (43) from the coupling position (Z1) into the decoupling position (Z2).

6. Household dishwasher according to claim 5, characterised in that the overload protection mechanism (43) comprises a housing element (47) connected to the overload element (46), wherein a spring element (48) is arranged between the overload element (46) and the housing element (47).

7. Household dishwasher according to claim 6, characterised in that, when the overload protection mechanism (43) is moved from the coupling position (Z1) into the decoupling position (Z2), the spring element (48) moves the overload element (46) linearly along the axis of rotation (30) of the gear wheel (36) with respect to the housing element (47).

8. Household dishwasher according to claim 6 or 7, characterised in that the spring element (48) is, at least in sections, received in the overload element (46).

9. Household dishwasher according to claim 4, characterised in that if the spray arm becomes blocked (17), the overload element (68) moves linearly perpendicular to an axis of rotation (30) of the gear wheel (36) in order to move the overload protection mechanism (43') from the coupling position (Z1) into the decoupling position (Z2).

10. Household dishwasher according to claim 9, characterised in that the overload protection mechanism (43') comprises a housing element (67) received in the gear wheel (36), wherein a spring element (69) is arranged between the housing element (67) and the overload element (68).

11. Household dishwasher according to claim 10, characterised in that when the overload protection mechanism (43') is moved from the coupling position (Z1) into the decoupling position (Z2), the spring element (69) moves the overload element (68) linearly perpendicular to the axis of rotation (30) of the gear wheel (36) with respect to the housing element (67).

12. Household dishwasher according to claim 10 or 11, characterised in that the overload element (68) is, at least in sections, received in the spring element (69).

13. Household dishwasher according to one of claims 1 - 12, characterised by a detection system (15) which can be used to detect whether the overload protection mechanism (43, 43') is in the coupling position (Z1) or the decoupling position (Z2).

14. Household dishwasher according to claim 13, characterised in that the detection system (15) detects a motor current (I) of the drive system (19, 19').