HOUSEHOLD DISHWASHER

Description

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

[0002] A dishwasher comprises a wash tub containing a spray arm for spraying the dishes with cleaning solution. The spray arm can have a boom and a spray arm satellite mounted rotatably on the boom. The spray arm satellite includes spray nozzles. The cleaning solution exiting the nozzles generates a driving torque based on momentum forces, causing the spray arm satellite to rotate relative to the boom. Different forces and torques can act on the spray arm satellite at each angular position due to these momentum forces. This can lead to uneven, and especially jerky, movement of the spray arm satellite. This needs to be improved.

[0003] EP 2 822 441 B1 describes a dishwasher with a wash tub and a spray arm rotatably mounted within the wash tub. The spray arm comprises a boom and a spray arm satellite rotatably mounted on the boom. US 1,592,452 A shows a dishwasher with a wash tub and a spray arm rotatably mounted within the wash tub. The spray arm comprises a boom and two spray arm satellites rotatably mounted on the boom.

[0004] JP 2861792 B2 describes a dishwasher with a wash tub and a spray arm that is rotatably mounted within the wash tub. The spray arm comprises a boom and a spray arm satellite that is rotatably mounted on the boom. WO 2018 / 228679 A1 shows a dishwasher with a wash tub and a spray arm that is rotatably mounted within the wash tub. The spray arm comprises a boom and a spray arm satellite that is rotatably mounted on the boom.

[0005] The JP H10127560 A describes a dishwasher with a wash tub and a rotating spray arm housed in the wash tub.

[0006] Against this background, one object of the present invention is to provide an improved household dishwasher.

[0007] The object of the present invention is achieved by the features of claim 1. The preferred embodiments are defined in the dependent claims.

[0008] Because the force vectors cancel each other out, smooth operation of both the spray arm satellite and the boom is always ensured. This prevents fluctuating or pulsating loads on the spray arm satellite's bearings on the boom, as well as on the boom's bearings themselves. Therefore, the smoother operation of the boom and spray arm satellite results in a longer service life with reduced material usage.

[0009] The washing tank is preferably cuboid in shape. The washing tank may have an openable door at the front. The spray arm is preferably rotatably mounted on the bottom of the washing tank, in particular on a pump housing of the washing tank. The fact that the items to be washed are "exposed" to washing solution and / or fresh water means, in this context, that the spray arm is designed to wet the items with washing solution and / or fresh water in order to clean them. The fact that the boom is "actively driven" means, in particular, that the boom is not set in rotation by washing solution and / or fresh water exiting spray nozzles. Rather, the drive element is provided for actively driving the boom. The drive element is an electric motor or comprises an electric motor.

[0010] Unlike the boom, the spray arm satellite is passively driven. "Passive" in this context means that the spray arm satellite does not include a drive element as previously mentioned, but is only set in rotation by the cleaning solution and / or fresh water exiting the spray nozzles. The fact that the spray nozzles are "designed" such that their force vectors cancel each other out in the plane means, in particular, that the spray nozzles are oriented differently in space and / or allow different volume flows of exiting cleaning solution and / or fresh water, such that the force vectors cancel each other out in the plane. Accordingly, the sum of the force vectors in the plane is zero or at least approximately zero.

[0011] The spray nozzles have different outlet cross-sections for the rinsing solution and / or the fresh water.

[0012] For example, a larger outlet cross-section allows more rinsing solution and / or fresh water to exit the respective spray nozzle. Consequently, the corresponding force vector is also greater compared to a spray nozzle with a smaller outlet cross-section. Alternatively, all spray nozzles can have an identical outlet cross-section. The outlet cross-section can, for example, have a circular geometry. However, it can also be oval, rectangular, or slotted.

[0013] According to another embodiment, the spray nozzles are inclined differently when viewed in the plane.

[0014] For example, the spray nozzles are inclined such that the force vectors are oriented perpendicular to the arms of the spray arm satellite. However, the spray nozzles can be inclined at any angle other than this perpendicular orientation. Alternatively, all spray nozzles can be inclined identically when viewed in the plane.

[0015] According to another embodiment, the spray nozzles are arranged at different distances from the axis of rotation.

[0016] For example, a spray nozzle with a larger outlet cross-section is positioned closer to the axis of rotation than a spray nozzle with a comparatively smaller outlet cross-section. The resulting force vector of the spray nozzle with the larger outlet cross-section therefore has a shorter lever arm than the force vector of the spray nozzle with the smaller outlet cross-section.

[0017] According to another embodiment, at least part of the spray nozzles is oriented perpendicular to the plane.

[0018] These spray nozzles make it possible, in particular, to wet items being washed in a dishwashing container located above the spray arm with washing solution and / or fresh water. The spray nozzles are arranged and their outlet cross-section is designed in such a way that preferably no tilting moment is applied to the spray arm satellite.

[0019] According to another embodiment, the spray arm satellite comprises several arms on which the spray nozzles are attached.

[0020] The number of arms is arbitrary. Preferably, the spray arm satellite comprises at least two arms. However, the spray arm satellite can also have three arms, which, for example, are positioned at uniform intervals around their circumferences.

[0021] According to a further embodiment, each arm includes at least one spray nozzle. This at least one spray nozzle can be oriented perpendicular to the plane. Preferably, however, each arm includes several spray nozzles.

[0022] According to another embodiment, the arms comprise differing arrangements of spray nozzles.

[0023] In this context, the term "arrangement" can be understood as the distance of the respective spray nozzles from the axis of rotation.

[0024] According to another embodiment, the spray nozzles are provided on the upper side of the arms.

[0025] Additionally, spray nozzles may also be provided on the underside of the arms. These may be suitable, for example, for cleaning the filter system of a household dishwasher.

[0026] According to another embodiment, at least part of the spray nozzles is inclined out of the plane.

[0027] The spray nozzles can be inclined at any angle relative to the plane.

[0028] Other possible implementations of the household dishwasher also include combinations of features or embodiments described previously or subsequently with regard to the exemplary embodiments, even if not explicitly mentioned. In such cases, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the household dishwasher.

[0029] Further advantageous embodiments 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 will be explained in more detail below with reference to preferred embodiments and the accompanying figures. Fig. 1 shows a schematic perspective view of an embodiment of a household dishwasher; Fig. 2 shows a schematic side view of an embodiment of a spray device for the household dishwasher according to Fig. 1 Fig. 3 shows a schematic top view of the spraying device according to Fig. 2 Fig. 4 shows a force polygon acting on the spraying device according to Fig. 2 acting forces; Fig. 5 shows another force polygon acting on the spray device according to Fig. 2 acting forces; Fig. 6 shows a schematic top view of another embodiment of a spray device for the household dishwasher according to Fig. 1 Fig. 7 shows a force polygon acting on the spraying device according to Fig. 6 acting forces; Fig. 8 shows another force polygon acting on the spray device according to Fig. 6 acting forces; Fig. 9 shows a schematic top view of another embodiment of a spray device for the household dishwasher according to Fig. 1 ; and Fig. 10 shows a further highly simplified schematic view of the spraying device according to Fig. 9 .

[0030] In the figures, identical or functionally equivalent elements have been given the same reference symbols, unless otherwise indicated.

[0031] The Fig. 1 Figure 1 shows a schematic perspective view of an embodiment of a household dishwasher 1. The household dishwasher 1 comprises a wash tub 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 wash tub 2. The wash tub 2 is preferably cuboid in shape. The wash tub 2 can be arranged in a housing of the household dishwasher 1. The wash tub 2 and the door 3 can form a wash chamber 4 for washing dishes.

[0032] Door 3 is in the Fig. 1 The door 3 is shown in its open position. It can be opened or closed by pivoting it about a pivot axis 5 located at its lower end. The door 3 can be used to open or close a loading opening 6 of the wash tank 2. The wash tank 2 has a base 7, a top 8 opposite the base 7, a rear wall 9 opposite the closed door 3, and two opposing side walls 10 and 11. The base 7, the top 8, the rear wall 9, and the side walls 10 and 11 can, for example, be made of stainless steel. Alternatively, the base 7 can, for example, be made of a plastic material.

[0033] The household dishwasher 1 further comprises at least one dishware holder 12 to 14. Preferably, several, for example three, dishware holders 12 to 14 can be provided, wherein the dishware holder 12 can be a lower dishware holder or a lower basket, the dishware holder 13 an upper dishware holder or an upper basket, and the dishware holder 14 a cutlery drawer. As the Fig. 1 As further shown, the dishware holders 12 to 14 are arranged one above the other in the washing container 2. Each dishware holder 12 to 14 can be selectively moved into or out of the washing container 2. In particular, each dishware holder 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.

[0034] The Fig. 2 Figure 1 shows a schematic side view of an embodiment of a spray device 15A for the household dishwasher 1. Fig. 3 Shows a schematic top view of the spray device 15A. The following refers to the Fig. 2 and 3 Reference was made at the same time.

[0035] The spray device 15A is preferably provided on the base 7 of the wash tank 2. The spray device 15A comprises a rotatably mounted spray arm 16 with a boom 17 and a spray arm satellite 18 rotatably mounted on the boom 17. The spray arm satellite 18 is rotatably mounted on the boom 17 about an axis of rotation 19. The boom 17, in turn, is rotatably mounted about an axis of rotation 20 on a pump housing 21 of the household dishwasher 1. However, the boom 17 can also be mounted on another area or component of the household dishwasher 1. The boom 17 is actively driven. For this purpose, a drive element 22 is provided. The drive element 22 is an electric motor. The spray device 15A comprises the spray arm 16 and the drive element 22.

[0036] The spray arm satellite 18 comprises a plurality of spray nozzles 23 to 28. The number of spray nozzles 23 to 28 is arbitrary. For example, six spray nozzles 23 to 28 are provided, which can be oriented differently. The spray nozzles 23 to 28 are suitable for generating spray jets with which the items to be washed can be treated with cleaning solution and / or fresh water F. The spray nozzles 23 to 28 are provided on the top of the spray arm satellite 18. "Top" here means facing away from the base 7. However, spray nozzles (not shown) can also be provided on the underside of the spray arm satellite 18. "Underside" here means facing towards the base 7. Preferably, however, the spray nozzles 23 to 28 are provided on only one side of the spray arm satellite 18. Alternatively, the spray arm satellite 18 can also have spray nozzles 23 to 28 on both the top and bottom sides.

[0037] The spray arm satellite 18 has several arms 29 to 31. The number of arms 29 to 31 is arbitrary. For example, three such arms 29 to 31 are provided, spaced apart from each other by a circumferential angle of 120°. However, only two arms 29 to 31 or more than three arms 29 to 31 can also be provided.

[0038] A screening system 32 is provided on the pump housing 21. The screening system 32 is multi-part and can, for example, comprise a coarse screen and a fine screen. The boom 17 preferably comprises several arms 33, 34. Preferably, two arms 33, 34 are provided, wherein the spray arm satellite 18 is rotatably mounted on the arm 33 about the axis of rotation 19. However, only one arm 33, 34 may also be provided.

[0039] The axes of rotation 19 and 20 are positioned parallel to each other and spaced apart. The boom 17 can also have spray nozzles 23 to 28 as mentioned previously. However, this is not mandatory. The boom 17 is actively driven, as mentioned previously. In contrast, the spray arm satellite 18 is not actively driven. Specifically, the spray arm satellite 18 is set in rotation by the flushing solution and / or fresh water F flowing out of the spray nozzles 23 to 28.

[0040] The rinsing solution and / or fresh water F exiting the spray nozzles 23 to 28 generates a driving torque M based on impulse forces. The driving torque M is in the orientation of the Fig. 3 The drive torque M is oriented counterclockwise. However, it can also be oriented in the opposite direction. The drive torque M sets the spray arm satellite 18 into rotation relative to the boom 17. The momentum forces are transmitted both to a bearing of the spray arm satellite 18 on the boom 17 and to a bearing of the boom 17 itself. This can lead to different forces and moments acting on the bearings at each angular position of the spray arm satellite 18. This results in uneven movement of the spray arm satellite 18 and consequently an undesirable fluctuating load. This needs to be improved.

[0041] For this purpose, the spray nozzles 23 to 28 are designed, both with regard to their orientation in space and with regard to the volume flow of cleaning solution and / or fresh water F exiting the respective spray nozzle 23 to 28, such that the forces resulting from the exit of the cleaning solution and / or fresh water F are approximately zero in every angular position of the spray arm satellite 18 and thus cancel each other out. As a result, only the drive torque M of the spray arm satellite 18, which remains constant and does not change depending on the angular position, is transmitted to the boom 17.

[0042] As the Fig. 3 The spray arm satellite 18 has two spray nozzles 23, 24 on its arm 29, which generate spray jets 35, 36 oriented opposite to the direction of rotation of the spray arm satellite 18. The spray nozzles 23, 24 are inclined relative to the arm 29. Force vectors F35, F36 result from the spray jets 35, 36, which cause the spray arm satellite 18 to rotate. The force vectors F35, F36 lie in a plane E1 spanned by an x-direction x and a y-direction y.

[0043] Furthermore, the spray arm satellite 18 includes spray nozzles 25, 26 provided on the arm 30, which are oriented perpendicular to the arm 30 and thus along a z-direction. The spray nozzles 25, 26 do not contribute to the drive torque M, as they do not generate any force vectors arranged in the plane E1. A spray nozzle 28 is provided on the arm 31, which, like the spray nozzles 25, 26, is oriented perpendicularly and thus along the z-direction.

[0044] The arm 31 is further equipped with a spray nozzle 27, which is arranged such that its spray jet 37 is parallel to and opposite to the spray jets 35, 36 of the spray nozzles 23, 24. The spray nozzle 27 thus has an inclination to generate the drive torque M and an inclination radially outwards. A force vector F37 results from the spray jet 37.

[0045] The force vectors F35, F36, and F37 all lie in the plane E1 and cancel each other out, so that any force resulting from the force vectors F35, F36, and F37 is zero or nearly zero. This applies to every angular position of the spray arm satellite 18. A fluctuating load on components of the spray arm 16 is thus reliably prevented.

[0046] The Fig. 4 und 5 Each example shows how the force vectors F35, F36, and F37 cancel each other out. In the example according to the Fig. 4 The force vectors F35 and F36 are equal in magnitude. In the example according to the Fig. 5 The force vectors F35 and F36 are of different magnitudes. This difference can result, for example, from the fact that the spray nozzles 23 and 24 have different outlet cross-sections for the rinsing solution and / or the fresh water F.

[0047] With this previously described design of the spray nozzles 23 to 28, a longer service life with reduced material usage is possible due to the smoother operation of the boom 17. Bearing wear is reduced. Pulsating or fluctuating loads on the entire drive train, which can include the drive element 22, a gearbox, and a seal, are avoided. Furthermore, the boom 17 operates with a visually appealing finish.

[0048] The Fig. 6 Figure 1 shows a schematic top view of another embodiment of a spray device 15B. The spray device 15B is essentially identical in design to the spray device 15A. The following discussion focuses solely on the differences between spray devices 15A and 15B.

[0049] The spray device 15B comprises spray nozzles 24, 26, 28 on its spray arm satellite 18, which are oriented vertically upwards, i.e., along the z-direction z. These spray nozzles 24, 26, 28 do not contribute to the drive torque M for driving the spray arm satellite 18. However, the spray nozzles 24, 26, 28 are designed such that the rinsing solution and / or the fresh water F exiting them does not exert a tilting moment on the spray arm satellite 18.

[0050] Furthermore, each arm 29, 30, 31 includes a spray nozzle 23, 25, 27, each oriented such that a spray jet 38, 39, 40 perpendicular to the respective arm 29, 30, 31 is generated. The spray jets 38, 39, 40 lie in the plane E1 and generate force vectors F38, F39, F40, which generate the driving torque M. The force vectors F38, F39, F40 lie in the plane E1 spanned by the x-direction x and the y-direction y. As in the Fig. 7 und 8 As shown, the sum of all force vectors F38, F39, F40 in the plane E1 is zero. The spray nozzles 23, 25, 27 have a common effective circle. This means that the spray nozzles 23, 25, 27 are all the same distance from the axis of rotation 19. For example, the force vectors F38, F39, F40 are each 0.3 N. Fig. 7 und 8 Each example shows how the force vectors F38, F39, F40 cancel each other out.

[0051] The Fig. 9 Figure 1 shows a schematic top view of another embodiment of a spray device 15C. The spray device 15C is essentially identical in design to the spray device 15B. The following discussion focuses solely on the differences between spray devices 15A and 15B.

[0052] The spray arm satellite 18 comprises three spray nozzles 24, 26, 28 which are oriented perpendicular to the spray arm satellite 18 and thus along the z-direction z. The spray nozzles 24, 26, 28 are designed with respect to their effective circle, i.e., their distance from the axis of rotation 19, and their diameter such that each arm 29, 30, 31 has the same moment in the z-direction z.

[0053] Furthermore, spray nozzles 23, 25, 27 are provided, which serve to drive the spray arm satellite 18. In contrast to the spray device 15B, the spray nozzles 23, 25, 27 are inclined outwards at an angle α of 15 to 30°. This eliminates the need for a fan nozzle inclined at 45° for corner cleaning. The spray nozzles 23, 25, 27 generate spray jets 38, 39, 40 and resulting force vectors F38, F39, F40. The force vectors F38, F39, F40 each have a magnitude of 0.3 N, for example.

[0054] The Fig. 10 This figure shows, using spray nozzle 23 as an example, how spray nozzles 23 to 28 can be modified to achieve the goal of ensuring that the sum of all force vectors F38, F39, F40 in the plane E1 is equal to zero. A distance a between the axis of rotation 19 and spray nozzle 23 can be changed to increase or decrease the effective area of ​​spray nozzle 23. The greater the distance a, the greater the lever arm with which the force vector F35 associated with spray nozzle 23 acts on the respective arm 29, 30, 31 of the spray arm satellite 18.

[0055] Furthermore, an inclination angle β of the force vector F35 arranged in the plane E1 can be changed by a corresponding orientation of the spray nozzle 23. The inclination angle β is defined as an angle spanning between a connecting line 41 and the respective force vector F35. Also, a Fig. 10The hatched area Q of the spray nozzle 23 can be changed. The larger the outlet area Q, the more rinsing solution and / or fresh water F can exit the spray nozzle 23 per unit of time.

[0056] Although the present invention has been described using exemplary embodiments, it can be modified in many ways. Reference symbols used:

[0057] 1 Household dishwasher 2 Wash tub 3 Door 4 Wash chamber 5 Swivel axis 6 Loading opening 7 Floor 8 Ceiling 9 Back wall 10 Side wall 11 Side wall 12 Dishwashing compartment 13 Dishwashing compartment 14 Dishwashing compartment 15A Spray device 15B Spray device 15C Spray device 16 Spray arm 17 Boom 18 Spray arm satellite 19 Rotary axis 20 Rotary axis 21 Pump housing 22 Drive element 23 Spray nozzle 24 Spray nozzle 25 Spray nozzle 26 Spray nozzle 27 Spray nozzle 28 Spray nozzle 29 Arm 30 Arm 31 Arm 32 Filter system 33 Arm 34 Arm 35 Spray jet 36 Spray jet 37 Spray jet 38 Spray jet 39 Spray jet 40 Spray jet 41 Connecting straight aDistance AExtraction direction EInsertion direction E1Level FFlushing liquid and / or fresh water F35Force vector F36Force vector F37Force vector F38Force vector F39Force vector F40Force vector MDrive torque Outlet cross-section xx-direction Q yy-direction zz-direction αInclination angle βInclination angle

Claims

1. Household dishwasher (1) with a dishwasher cavity (2) and a spray arm (16) for applying washing liquor and / or fresh water (F) to items to be washed received in the dishwasher cavity (2), wherein the spray arm (16) comprises a jib (17) driven actively with the aid of a drive element (22) and a spray arm satellite (18) mounted on the jib (17) so as to be rotatable about an axis of rotation (19), wherein the spray arm satellite (18) comprises spray nozzles (23-28) applied with washing liquor and / or the fresh water (F), wherein spray jets (35 - 40) emanating from the spray nozzles (23 - 28) set the spray arm satellite (18) to rotate, wherein the spray nozzles (23-28) are designed such that force vectors (F35 - F40) resulting from the emanating spray jets (35-40) cancel one another out in a plane (E1) oriented at a right angle to the axis of rotation (19), characterised in that the spray nozzles (23 - 28) comprise exit cross-sections (Q) which differ from one another for the washing liquor and / or the fresh water (F).

2. Household dishwasher according to claim 1, characterised in that the spray nozzles (23 - 28) are inclined differently when viewed in the plane (E1).

3. Household dishwasher according to claim 1 or 2, characterised in that the spray nozzles (23- 28) are arranged at different distances from the axis of rotation (19).

4. Household dishwasher according to one of claims 1 - 3, characterised in that at least one part of the spray nozzles (23 - 28) is oriented at a right angle to the plane (E1).

5. Household dishwasher according to one of claims 1 - 4, characterised in that the spray arm satellite (18) comprises a number of arms (29 - 31) to which the spray nozzles (23 -28) are attached.

6. Household dishwasher according to claim 5, characterised in that each arm (29- 31) comprises at least one spray nozzle (23 - 28).

7. Household dishwasher according to claim 5 or 6, characterised in that the arms (29-31) comprise arrangements of spray nozzles (23 - 28) which differ from one another.

8. Household dishwasher according to one of claims 5 - 7, characterised in that the spray nozzles (23 - 28) are provided on the top of the arms (29 - 31).

9. Household dishwasher according to one of claims 1 - 8, characterised in that at least one part of the spray nozzles (23 - 28) is inclined out of the plane (E1).