Dishwasher, method and computer program product

Abstract

The invention relates to a dishwasher (1), in particular a domestic dishwasher, having at least one rinsing device (20) which is actively driven by a drive device (15) for loading rinsing liquid for rinsing items which can be arranged in a rinsing container (2) of the dishwasher (1), wherein the drive device (15) comprises an electric motor (16) for actively driving the at least one rinsing device (20) and a detection unit (16A) for detecting a motor rotational speed (SIG) of the electric motor (16), and a control device (25) which is set up to determine a blockage of the at least one rinsing device (20) depending on the detected motor rotational speed (SIG).

Description

Technical Field

[0001] This invention relates to a dishwasher, a method of operating a dishwasher, and a computer program product. Background Technology

[0002] Known dishwashers typically have a rotatably mounted rinsing unit, driven, for example, by hydraulic backwash or a motor. During dishwasher operation, items to be rinsed (such as knives or plates) may extend from the dish rack and into the rinsing unit's path. This can obstruct the rinsing unit. If the rinsing unit stops rotating, cleaning effectiveness will be affected. Therefore, it is desirable to identify obstructions to the rinsing unit and take countermeasures.

[0003] Preferably, the dishwasher's rinsing device is actively driven by a motor. This has the advantage that the rinsing device can rotate at different speeds and / or can stop at appropriate locations, for example, to form an enhanced rinsing zone.

[0004] US 8,357,246 B2 discloses a dishwasher with a motor-driven wash arm. Detection and evaluation of the motor current enables the determination of obstruction of the wash arm. US 8,734,594 B2 and US 9,681,790 B2 disclose other conventional dishwashers. Summary of the Invention

[0005] In this context, one object of the present invention is to improve the operation of the dishwasher.

[0006] According to a first aspect, a dishwasher, particularly a household dishwasher, is proposed, comprising: at least one rinsing device driven by a drive unit for loading detergent onto items that can be arranged in the rinsing container of the dishwasher. The drive unit includes a motor for actively driving the at least one rinsing device and a detection unit for detecting the motor speed. A control unit is configured to determine a blockage of the at least one rinsing device based on the detected motor speed.

[0007] The advantage of this dishwasher is its ability to identify obstructions in the rinsing unit based on the motor speed. If an obstruction is present, appropriate countermeasures can be taken to minimize its impact on the rinsing effect. The dishwasher can therefore achieve optimal washing results even in the presence of obstructions. On the one hand, this protects the items being rinsed because it prevents the rinsing unit from remaining in an obstructed position, and only items positioned in that position are treated with rinsing liquid. On the other hand, it saves resources because it avoids repeating the washing cycle on the same items, which would otherwise not have been adequately cleaned. Obstructions in the rinsing unit can be caused, for example, by the items being rinsed or by dirt that has seeped into the rinsing unit's transmission system.

[0008] The drive unit particularly includes an electric motor, such as a brushless DC motor (BLDC) or a brushless AC motor (BLAC). Other types of motors can also be suitable. The drive unit is, for example, driven by a control unit. The drive unit is configured to actively drive the rinsing device. In the present case, "actively driven" means that the drive unit applies torque to the rinsing device. Therefore, in the present case, "active" drive should not be specifically understood as the rinsing arm rotating by means of the nozzle. Active drive can be achieved, in particular, at an adjustable speed. The drive unit can also be configured to stop the rinsing device at a specific position or a specific rotation angle and / or move the rinsing device back and forth.

[0009] The rinsing device is rotatably supported and designed, for example, as a rinsing arm. The rinsing device is configured to spray rinsing fluid onto the items being rinsed. For this purpose, the rinsing device preferably includes multiple nozzles from which the rinsing fluid is sprayed under overpressure. The rinsing device includes a hydraulic system configured to guide the rinsing fluid from, for example, a connector arranged on the axis of rotation of the rinsing device to the nozzles. The rinsing device may optionally include one or more satellite rinsing devices.

[0010] In this application, the term "rinsing solution" is understood to refer to any liquid that can be used to wash items in a dishwasher. For example, rinsing solutions include freshly supplied tap water, deionized tap water, tap water mixed with detergent, etc. The rinsing solution can also include dirt that has been separated from the items being rinsed.

[0011] The detection unit of the drive device includes, for example, Hall sensors, optical encoders, incremental encoders, etc.

[0012] Alternatively or additionally, the detection unit can measure the zero-crossing of a single voltage, particularly the back electromotive force (EMF), induced in the motor windings. Advantageously, the back EMF is evaluated anyway for motor regulation, thus eliminating the need for additional components in this case.

[0013] Control devices can be implemented using hardware and / or software technologies. In hardware implementation, the control device can be designed as, for example, a computer or a microprocessor. In software implementation, the control device can be designed as a computer program product, function, routine, part of program code, or an executable object.

[0014] The control device is configured to determine the obstruction of the flushing device based on the detected motor speed. To do this, the control device, for example, analyzes the signal curve of the motor speed and / or compares it with a target value for the motor speed.

[0015] According to one embodiment of the dishwasher, an overload protection device is installed between the motor and the rinsing device. When the rinsing device is blocked, the overload protection device automatically changes from a coupled state where there is force transmission between the motor and the rinsing device to a decoupled state where the force transmission between the motor and the rinsing device is disconnected.

[0016] By incorporating an overload protection device, overload of the drive unit can be reliably prevented. Specifically, this prevents damage to the drive elements or transmission mechanism of the drive unit. The fact that the overload protection device "automatically" moves from the coupled state back to the decoupled state and then back again specifically means that the overload protection device can move from the coupled state to the decoupled state or vice versa without the need for an active drive element and / or sensor. In the decoupled state of the overload protection device, the flushing device is no longer actively driven, and the motor has no rotating load.

[0017] The overload protection device is preferably triggered at a maximum torque between 0.25 Nm and 2 Nm, and more preferably between 0.4 Nm and 1 Nm. Before the overload protection device trips, the forces acting on the washing items, the washing arm, and the drive unit are thus limited to a smaller upper limit. Simultaneously, the maximum torque is high enough that the motor speed decreases slightly before the overload protection device trips, thus allowing reliable detection of changes in motor speed. It should be noted that, for example, adjusting the motor speed to a preset target value cannot compensate for too rapid a speed drop, as otherwise it might no longer be possible to detect speed fluctuations caused by obstruction. Therefore, the adjustment must be set in such a way that speed fluctuations remain sufficiently large when obstruction occurs.

[0018] According to another embodiment of the dishwasher, the drive unit is arranged outside the rinsing container, wherein an output shaft for transmitting the torque of the motor to the rinsing device is provided, and an overload protection device is provided between the output shaft and the rinsing device, wherein when the overload protection device is in a coupled state, the rotation angle of the output shaft and the rotation angle of the rinsing device are in a predetermined ratio.

[0019] In this embodiment, when the overload protection device is in the coupled state, the rotation angle of the flushing device can be advantageously inferred from the rotation angle of the output shaft. The rotation angle of the output shaft can also be detected within the drive unit, for example, using a rotary encoder or incremental sensor. Alternatively or additionally, the rotation angle of the output shaft can be inferred from the rotation angle of the motor.

[0020] The output shaft protrudes through the wall of the flushing container and is sealed with a seal so that no flushing fluid can flow out of the flushing container on the output shaft.

[0021] The rotation axis of the output shaft of the drive unit and the rotation axis of the flushing arm are preferably arranged parallel to each other and spaced a certain distance apart.

[0022] In one embodiment of the dishwasher, the drive unit includes a transmission unit disposed between the motor and the rinsing device, which is used to provide a predetermined transmission ratio for driving the rinsing device.

[0023] In this implementation, the transmission unit is arranged between the motor and the output shaft.

[0024] The drive unit is preferably designed so that the output shaft and the rinsing device rotate at a speed of 0-20 rpm. The drive unit is preferably configured to provide a reduction ratio in the range of 200 / 1 to 1000 / 1. This means, for example, that the motor rotates 200 rpm while the output shaft rotates only once.

[0025] According to another embodiment of the dishwasher, the control device is configured to determine the obstruction of the rinsing device based on a comparison between a predetermined target rotation speed and a detected motor rotation speed.

[0026] For example, the target rotational speed is 500 revolutions per second at a given time point. If the detected motor speed has a different value, especially a lower one, this indicates the presence of obstruction. It's important to note that during a cleaning process, the target rotational speed can vary at different times, depending on the specific cleaning program.

[0027] In one embodiment, the control device is configured to perform signal analysis on the detected motor speed and determine the obstruction of the flushing device based on the result of the signal analysis.

[0028] Signal analysis specifically includes the formation of the time derivative and / or the implementation of frequency analysis. In particular, it is possible to identify sudden changes in rotational speed based on jumps in the time derivative.

[0029] According to another embodiment of the dishwasher, the control device is configured to determine the obstruction of the rinsing device based on the fact that the detected deviation between the motor speed and the target speed is greater than a predetermined threshold.

[0030] For example, the predetermined threshold may be specified as an absolute value or as a relative value, depending, for example, on the target RPM and / or a combination of these options. For instance, the predetermined threshold could be 50 RPM. Alternatively, the predetermined threshold could be 10% of the target value, i.e., 100 RPM for a target value of 1000 RPM. Or, the predetermined threshold could include a combination of these, such as 10% of the target and at least 50 RPM.

[0031] According to another embodiment of the dishwasher, the control device is configured to output an instruction signal to the user of the dishwasher based on the determination of obstruction of the rinsing device.

[0032] For example, the dishwasher includes a speaker for outputting audible indication signals and / or a display element for outputting visual indication signals. In a preferred embodiment, the dishwasher includes a communication unit configured to transmit indication signals to an external device, such as a user's mobile device, particularly a smartphone, computer, etc., wherein the external device is configured to output indication signals to the user. For example, a corresponding application runs on the external device, which causes to output an indication to the user upon receiving an indication signal from the dishwasher.

[0033] This way, the user can be notified when an obstruction occurs. The user can then resolve the obstruction manually and / or notify customer service, for example.

[0034] According to one aspect, a system comprising a dishwasher according to the first aspect and an external device is proposed. The dishwasher includes a communication unit configured to transmit an indication signal to the external device. The external device is configured to output the indication signal to a user. For example, a corresponding application runs on the external device, which, upon receiving the indication signal from the dishwasher, causes the indication to be output to the user.

[0035] According to another embodiment of the dishwasher, the control device is configured to determine the blocking position of the rinsing device.

[0036] The blocking position includes, in particular, the rotation angle of the flushing device.

[0037] The blocking position can be derived, for example, from the position of the motor that determines the blocking. If no overload protection device is installed between the motor and the flushing device, i.e., the motor and the flushing device are permanently coupled, there is a ratio between the motor position and the flushing device position determined by the transmission system. If an overload protection device is present, the motor rotates independently of the flushing device in the decoupled state. In this case, the overload protection device is preferably designed such that a coupling state can only be established when there is a certain relative rotational position between the motor and the flushing device or between the output shaft and the flushing device. The motor or output shaft reaches this position once per revolution, thus the overload protection device switches to the coupled state. If the blocking still exists, the overload protection device returns to the decoupled state. This coupling / decoupling can be determined based on the detected motor speed. The motor position at the first decoupling thus corresponds to the blocking position of the flushing device.

[0038] According to another embodiment of the dishwasher, the control device is configured to output instructions to the user of the dishwasher based on the determined obstruction position.

[0039] The indication preferably includes the obstruction position. For example, the indication can include a graphical representation of the obstruction position. This allows the user to easily check the obstruction and remove it if necessary. According to another embodiment of the dishwasher, the control device is configured to reverse the rotation direction of the motor when the rinsing device is obstructed.

[0040] If the motor's rotation direction changes, the rotation direction of the actively driven flushing device also changes. This means the flushing device is moved away from where an obstruction exists. Depending on the nature of the obstruction, such as items protruding into the flushing device's range of motion, the obstruction may also occur in a different rotational direction. If the obstruction is caused by dirt, the dirt can be removed by changing the rotation direction.

[0041] According to another embodiment of the dishwasher, a detection unit is provided for detecting the movement of the rinsing device, wherein the control device is configured to determine the obstruction of the rinsing device based on the detected motor speed and the detection of the movement of the rinsing device.

[0042] In this embodiment, obstruction of the rinsing device can be verified. The detection unit can be, for example, a rotary encoder or a Hall sensor on the drive shaft of the rinsing device, which determines the sweeping of the rinsing device over a specific position in the rinsing container, wherein the rinsing device has a magnet, or a camera, which determines the movement of the rinsing device based on image analysis. In particular, it is advantageous to design the detection unit as a Hall sensor combined with a magnet arranged in or on the rinsing device, because in this case the Hall sensor can be arranged outside the rinsing container.

[0043] According to another embodiment of the dishwasher, the control device is configured to determine the angular range in which the rinsing device can rotate freely and drive the motor so that the rinsing device rotates only within the determined angular range.

[0044] In this embodiment, specifically, two blocking positions are determined, wherein the angle range between the two blocking positions is a free angle range.

[0045] For example, the rinsing device is designed to include two opposing rinsing arms, each of the same length. When rotated in a first direction of rotation, a blockage is established, for example, at an angle of approximately 90°. The rinsing arm then rotates in another direction, and a blockage is again established at an angle of approximately 270°, i.e., after the rinsing arm has rotated about half a turn. The corresponding blockage positions correspond to the contact of the corresponding handles of the rinsing arm. In this case, a control device drives a drive mechanism to rotate the rinsing arm back and forth between 90° and 270°. In this way, items can still be rinsed despite the presence of a blockage.

[0046] According to another embodiment of the dishwasher, the control device is configured to set the torque provided by the motor.

[0047] For example, for this purpose, the control device controls the drive current used to operate the motor and / or the voltage applied to the motor. This can be achieved, for example, by setting the pulse duty cycle.

[0048] In particular, even with overload protection devices present, limiting the torque can be advantageous in order to force the motor to stop. For this purpose, the torque must be set so that it is insufficient to trigger or decouple the overload protection device. Therefore, when obstruction occurs, the motor also stops. Thus, the motor position corresponding to the obstruction position can be determined.

[0049] According to another embodiment of the dishwasher, the control device is configured to start the motor after the dishwasher door has been closed, causing the rinsing device to perform at least one complete rotation in the rinsing container.

[0050] The advantage of this is that it allows for immediate identification of any obstructions after the door is closed. If an obstruction is present, the user (who is still near the dishwasher in this case) can be instructed accordingly and, preferably, resolve the obstruction directly.

[0051] This movement of the flushing device can also be described as a trial run.

[0052] In this design, a trial run is only provided when the user initiates the cleaning process via programming.

[0053] In another embodiment, a trial run can be provided each time the door is closed. In a preferred embodiment, a trial run is always provided when it is determined that the load of items being rinsed in the dishwasher has changed. The change in load can be determined, for example, based on images and / or weight measurements of the items being rinsed.

[0054] In a dishwasher implementation, the rinsing device includes a lower rinsing arm, an upper rinsing arm, and / or a top rotator.

[0055] The corresponding flushing arm particularly includes an actively driven boom and can include flushing arm satellites rotatably mounted on the boom. The flushing arm satellites are preferably not actively driven, but rather driven by the same flushing fluid sprayed from nozzles.

[0056] According to the second aspect, a method for operating a dishwasher, particularly a household dishwasher, is proposed. The dishwasher has at least one rinsing device driven by a drive unit, the rinsing device being used to apply rinsing liquid to items that can be arranged in the rinsing container of the dishwasher. In the first step, a motor of the drive unit is driven to actively drive the rinsing device. In the second step, the motor speed of the drive unit is detected. In the third step, an obstruction of the rinsing device is determined based on the detected motor speed.

[0057] The implementation methods and features described for the proposed dishwasher are correspondingly applicable to the proposed method. This method possesses the same advantages as those explained according to the dishwasher.

[0058] According to the third aspect, a computer program product is proposed, which includes instructions that, when executed by a computer, cause the computer to perform the method according to the second aspect.

[0059] Computer program products, such as computer program components, can be provided as storage media, such as memory cards, USB drives, CD-ROMs, DVDs, and in the form of files downloadable from the network server, for example, by means of the computer program product or computer program component, over a wireless communication network.

[0060] Other possible embodiments of the invention include combinations of features or embodiments not explicitly mentioned above or below as described above or below. Those skilled in the art will also add individual aspects as improvements or supplements to the corresponding basic forms of the invention. Attached Figure Description

[0061] Further advantageous improvements and aspects of the invention are the subject of embodiments of the invention described below. The invention will now be explained in more detail based on preferred embodiments with reference to the accompanying drawings.

[0062] Figure 1 A schematic perspective view of an embodiment of a dishwasher is shown;

[0063] Figure 2 A schematic cross-sectional view of another embodiment of the dishwasher is shown;

[0064] Figure 3 A graph showing the rotation angle of the output shaft versus the detected motor speed is presented, and

[0065] Figure 4 A schematic block diagram of an embodiment of a method for operating a dishwasher is shown.

[0066] Unless otherwise stated, the same or functionally identical elements in the figures are given the same reference numerals. Detailed Implementation

[0067] Figure 1A schematic perspective view of one embodiment of a dishwasher 1 is shown, which is designed herein as a household dishwasher. The household dishwasher 1 includes a rinsing container 2, which can be closed, particularly watertight, by a door 3. For this purpose, a sealing device can be provided between the door 3 and the rinsing container 2. The rinsing container 2 is preferably rectangular. The rinsing container 2 can be arranged within the housing of the household dishwasher 1. The rinsing container 2 and the door 3 can form a rinsing space 4 for rinsing items.

[0068] exist Figure 1 The diagram shows door 3 in its open position. Door 3 can be closed or opened by pivoting about a pivot 5 located at its lower end. With the aid of door 3, the loading opening 6 of the flushing container 2 can be closed or opened. The flushing container 2 has a base plate 7, a top plate 8 opposite to the base plate 7, a rear wall 9 opposite to the closed door 3, and two opposing side walls 10, 11. The base plate 7, top plate 8, rear wall 9, and side walls 10, 11 can be made of, for example, stainless steel. Alternatively, the base plate 7 can be made of, for example, plastic material.

[0069] The household dishwasher 1 also has at least one rinsing item receiving section 12 to 14. Preferably, multiple (e.g., three) rinsing item receiving sections 12 to 14 can be provided, wherein the rinsing item receiving section 12 is a lower rinsing item receiving section or lower bracket, the rinsing item receiving section 13 is an upper rinsing item receiving section or upper bracket, and the rinsing item receiving section 14 serves as a dish drawer. Furthermore... Figure 1 As shown, the rinsing item receiving portions 12 to 14 are arranged vertically overlapping each other in the rinsing container 2. Each rinsing item receiving portion 12 to 14 can be moved into or out of the rinsing container 2. In particular, each rinsing item receiving portion 12 to 14 can be pushed into or moved into the rinsing container 2 in the insertion direction E, and pulled out or removed from the rinsing container 2 in the extension direction A opposite to the insertion direction E.

[0070] A rinsing device 20 is arranged on the base plate 7. For example, it is a rinsing arm. The rinsing arm 20 can have satellite rinsing arms (not shown). The rinsing arm 20 is designed to output rinsing fluid to the items arranged in the rinsing item containers 12 to 14. The rinsing arm 20 is rotatably mounted, wherein the torque for rotating the rinsing arm 20 is provided by a drive unit 15. The drive unit 15 is preferably arranged outside the rinsing container 2, in this example below the floor 7. The drive unit 15 particularly includes a motor 16 (see...). Figure 2 ) and detection unit 16A (see Figure 2 ), used to detect the motor speed 21 of motor 16 (see Figure 3 ).

[0071] A control device 25 is also arranged at the door 3 of the household dishwasher 1. The control device 25 is configured, for example, to execute one of a plurality of cleaning programs. Specifically, the control device 25 is configured to determine the obstruction of the washing arm 20 based on the detected motor speed 21. For example, the washing arm 20 is in the absence of an overload protection device 19 (see...). Figure 2 In the case of obstruction of the rinsing arm 20, the motor speed 21 will drop to zero because the rinsing arm 20 stops, and therefore the motor 16 also stops. If an obstruction is detected, the control device 25 can, for example, drive the drive device 15 to rotate the rinsing arm 20 in the opposite direction. If an obstruction also occurs in this direction of rotation, the rinsing arm 20 can rotate back and forth, for example, between the two points where the rinsing arm 20 encounters the obstacle causing the obstruction. This is also known as the swing operation of the rinsing arm 20. This ensures that the items being rinsed are still cleaned even though the rinsing arm 20 is obstructed. In addition, the control device 25 can notify the user of the dishwasher 1 of the obstruction. This can be achieved by outputting audible and / or visual indication signals and / or by transmitting the indication to an external device (especially a mobile device) belonging to the user. The user can then react and resolve the obstruction or report it to customer service, as long as the obstruction is not caused by the items being rinsed, etc.

[0072] Figure 2 A schematic cross-section of another embodiment of dishwasher 1 is shown. Dishwasher 1 particularly features according to... Figure 1 The features explained for household dishwashers, even if they are not partially displayed. Figure 1 middle.

[0073] In particular, Figure 2 The transmission system from the drive unit 15 to the actively driven rinsing device 20 is shown in detail. The drive unit 15 is arranged below the bottom plate 7 of the rinsing container 2. The drive unit 15 includes a motor 16 and a detection unit 16A, which is configured to detect the motor speed 21 of the motor 16 (see [reference]). Figure 3 The motor 16 drives the output shaft 17. This can be achieved, in particular, using a transmission device (not shown) that increases or decreases the motor speed 21 by a predetermined factor. The output shaft 17 rotates according to the motor 16, wherein the direction of rotation is freely adjustable. Here, the rotation of the output shaft 17 is proportional to the rotation of the motor 16, wherein the transmission ratio represents a proportionality factor. Without a transmission device, such as... Figure 2 As shown, the scaling factor is 1, and the arrow from motor 16 to output shaft 17 indicates force transmission.

[0074] The output shaft 17 passes through and extends into the bottom plate 7 of the rinsing container 2. Here, the output shaft 17 is sealed, for example with a shaft sealing ring, to prevent rinsing fluid leakage. Specifically, the output shaft 17 is coupled to a coupling unit 18 arranged in the rinsing container 2. In this example, the coupling unit 18 includes an overload protection device 19. If the rinsing device 20 is blocked, the overload protection device 18 automatically transitions from a coupled state (power transmission between the motor 16 and the rinsing device 20) to a decoupled state (disconnection of force transmission between the motor 16 and the rinsing device 20). In the coupled state, as indicated by the arrow, the overload protection device 18 transmits force from the output shaft 17 to the drive shaft 20A of the rinsing device 20.

[0075] The flushing device 20 is rigidly connected to the drive shaft 20A, for example, and rotates accordingly with it. The overload protection device is preferably designed such that a coupling state can be generated at exactly one specific relative rotational position between the output shaft 17 and the drive shaft 20A. Therefore, in the coupled state, the specific rotational position of the output shaft 17 corresponds to the specific rotational position of the drive shaft 20A and thus corresponds to the specific rotational position of the flushing device 20.

[0076] In one embodiment (not shown), the drive unit 15 further includes a sensor for detecting the rotational position of the output shaft 17. The sensor is designed as, for example, a magnetic or optical encoder. In the coupled state, the rotational position of the rinsing device 20 can be inferred from the detected rotational position of the output shaft 17. The obstruction position of the rinsing device 20 is therefore known. Appropriate measures can be taken based on the known obstruction position. For example, the obstruction position can be graphically represented by providing a visual output indication to the user of the dishwasher 1, allowing the user to easily check the obstruction and remove it if necessary.

[0077] Figure 3 Two charts are shown; the upper chart shows output axis 17 (see...). Figure 2 rotation angle The following diagram shows the motor speed (RPM) of the motor 16 driving the flushing device 20 (see Figure 1). Figure 2 Both graphs share a common time axis t. Each graph represents an exemplary curve, for example, corresponding to a transmission system with overload protection device 19 (see...). Figure 2 dishwashers, for example Figure 2 Dishwasher 1.

[0078] The graph above shows the curve of the rotation angle 21 of the output shaft 17. As mentioned above, the output shaft 17 rotates at a substantially constant angular velocity. Changes in the motor speed SIG proportionally affect the angular velocity of the output shaft 17.

[0079] The following chart shows the detected motor speed SIG. Adjusting the motor speed SIG to the target value RS. Fluctuations in the motor speed SIG can be observed at two time points, t1 and t2. These fluctuations occur during the two rotations of the output shaft 17 shown, at the same rotation angle of the output shaft 17. In the case of flushing device 20 (see...) Figure 1 Or 2) When locked, fluctuations are triggered by the coupling / decoupling of the overload protection device 19. When the overload protection device 19 is coupled and the flushing device 20 is locked, the drivetrain will be tensioned until the overload protection device 19 is triggered. This causes a decrease in the motor speed SIG. When the overload protection device is decoupled, the drivetrain relaxes again and the motor speed SIG suddenly increases again. The motor 16 is now rotating without load, so the motor speed SIG can briefly have an increased value until it is readjusted by adjustment.

[0080] To determine whether the speed fluctuation is caused by obstruction of the flushing device 20, two thresholds th1 and th2 are displayed. If one or both of these thresholds th1 and th2 are exceeded, it can be determined that the flushing device 20 is obstructed. Therefore, the control device 25 (see...) Figure 1 For example, it is configured to compare the detected motor speed SIG with at least one threshold th1, th2. Figure 3 As shown, in order to reliably identify obstructions, it is advantageous to wait for the output shaft 17 to rotate two or more times to see if the coupling / decoupling is repeated at the same rotational position of the output shaft 17.

[0081] As a supplement and / or alternative to comparing the motor speed SIG with thresholds th1 and th2 associated with the target value RS, the control device 25 can be configured to determine the local maximum / minimum values ​​(not shown) of the motor speed SIG through curve analysis. In this case, for example, if the first time derivative of the motor speed SIG is considered, zero crossings will exist at the local maximum / minimum values, which can be detected.

[0082] Figure 4 A diagram showing the operation of dishwasher 1 (e.g.) Figure 1 or Figure 2 A schematic block diagram illustrating an embodiment of a method for a dishwasher 1. The dishwasher 1 has at least one drive unit 15 (see [link to diagram]). Figure 1 Or 2) Driven flushing device 20 (see Figure 1 Or 2), used to apply rinsing fluid to a rinsing container 2 that can be arranged in the dishwasher 1 (see Figure 1 Or 2) on the rinsing items. In the first step S1, the motor 16 of the drive unit 15 for actively driving the rinsing device 20 (see Figure 2 In the second step S2, the motor speed SIG of the motor 16 of the drive unit 15 is detected (see...). Figure 3 In the third step S3, the obstruction of the flushing device 20 is determined based on the detected motor speed SIG.

[0083] In one embodiment, the method further includes the following steps. Once a blockage of the flushing device 20 is determined, for example according to... Figure 3 As described, motor 16 is controlled such that the torque provided is insufficient to release overload protection device 19 (see...). Figure 2 This can be achieved, for example, by setting the duty cycle to reduce the effective voltage used by the motor 16. When the output shaft 17 completes one full revolution and the overload protection device 19 returns to the coupled state, the torque of the motor 16 is insufficient to decouple the overload protection device 19 again.

[0084] Therefore, motor 16 stops. The angular position of motor 16 corresponding to the blocking position is stored. The torque limitation is now released again and motor 16 rotates in another direction. As a result, flushing device 20 is also driven in the other direction. Flushing device 20 rotates until it encounters an obstacle causing the blockage from the other side. The blockage is determined based on the detected motor speed SIG and the torque of motor 16 is limited again to determine and store a second blocking position, which relates to another rotational direction of flushing device 20. Therefore, in particular, the angular range in which flushing device 20 can rotate freely is determined. Flushing device 20 is now able to pivot back and forth within a known range.

[0085] Although the invention has been described with reference to embodiments, it can be modified in many ways.

[0086] List of reference numerals

[0087] 1. Dishwasher

[0088] 2. Rinse the container

[0089] 3 doors

[0090] 4. Rinse Space

[0091] 5 Pivot

[0092] 6 Loading port

[0093] 7. Base plate

[0094] 8. Top Slab

[0095] 9. Rear wall

[0096] 10 Sidewalls

[0097] 11 Sidewalls

[0098] 12. Rinse Items Container

[0099] 13. Rinse Items Container

[0100] 14. Rinse Items Container

[0101] 15. Drive unit

[0102] 16 motors

[0103] 16A Detection Unit

[0104] 17 Output shaft

[0105] 18 Coupling Units

[0106] 19. Overload protection device

[0107] 20. Flushing device

[0108] 20A shaft

[0109] 21. Rotation angle

[0110] 25 Control device

[0111] Cp rotation angle

[0112] A. Pulling direction

[0113] E Insertion direction

[0114] RPM speed

[0115] RS target speed

[0116] 51 Methods and Steps

[0117] 52 Methods and Steps

[0118] S3 Method Steps

[0119] SIG motor speed

[0120] T Timeline

[0121] t1 time point

[0122] t2 time point

[0123] th1 threshold

[0124] th2 threshold.

Claims

1. A dishwasher (1) comprising: at least one rinsing device (20) actively driven by a drive unit (15), the rinsing device being used to apply rinsing liquid to rinsing items that can be arranged in a rinsing container (2) of the dishwasher (1), wherein, The drive unit (15) includes a motor (16) for actively driving at least one of the flushing devices (20) and a detection unit (16A) for detecting the motor speed (SIG) of the motor (16); and a control unit (25) configured to determine the obstruction of at least one of the flushing devices (20) based on the detected motor speed (SIG), the control unit (25) being configured to determine the obstruction position of the flushing device (20), the obstruction position including the rotation angle of the flushing device. An overload protection device (19) is provided between the motor (16) and the flushing device (20). The overload protection device automatically transitions from a coupled state to a decoupled state when the flushing device (20) is obstructed. In the coupled state, there is a force transmission between the motor (16) and the flushing device (20). In the decoupled state, the force transmission between the motor (16) and the flushing device (20) is disconnected. The drive device (15) is arranged outside the flushing container (2). An output shaft (17) is provided for transmitting torque from the motor (16) to the flushing device (20). The overload protection device (19) is arranged between the output shaft (17) and the flushing device (20). The overload protection device is designed such that a coupling state can be generated at exactly one specific relative rotational position between the output shaft (17) and the drive shaft (20A) of the flushing device.

2. The dishwasher according to claim 1, characterized in that, The dishwasher in question is a household dishwasher.

3. The dishwasher according to claim 1, characterized in that, The control device (25) is configured to determine the obstruction of the flushing device (20) based on a comparison between a predetermined target rotational speed (RS) and a detected motor rotational speed (SIG).

4. The dishwasher according to claim 3, characterized in that, The control device (25) is configured to determine the obstruction of the flushing device (20) based on the detection that the deviation between the motor speed (SIG) and the target speed (RS) is greater than a predetermined threshold (th1, th2).

5. The dishwasher according to any one of claims 1-4, characterized in that, The control device (25) is configured to output an instruction signal to the user of the dishwasher (1) based on the determination of the obstruction of the rinsing device (20).

6. The dishwasher according to any one of claims 1-4, characterized in that, The control device (25) is configured to output an instruction signal to the user of the dishwasher (1) according to the determined blocking position.

7. The dishwasher according to any one of claims 1-4, characterized in that, A detection unit is provided for detecting the movement of the flushing device (20), wherein the control device (25) is configured to determine the obstruction of the flushing device (20) based on the detected motor speed (SIG) and the detection of the movement of the flushing device (20).

8. The dishwasher according to any one of claims 1-4, characterized in that, The control device (25) is configured to reverse the rotation direction of the motor (16) when the flushing device (20) is blocked.

9. The dishwasher according to any one of claims 1-4, characterized in that, The control device (25) is configured to determine the range of angles within which the rinsing device (20) can rotate freely, and drive the motor (16) such that the rinsing device (20) rotates only within the determined range of angles.

10. The dishwasher according to any one of claims 1-4, characterized in that, The control device (25) is configured to set the torque of the motor (16).

11. The dishwasher according to any one of claims 1-4, characterized in that, The control device (25) is configured to drive the motor (16) after the door (3) of the dishwasher (1) is closed, so that the rinsing device (20) performs at least one complete rotation in the rinsing container (2).

12. A method for operating a dishwasher (1), the dishwasher having at least one rinsing device (20) actively driven by a drive unit (15), the rinsing device being used to apply rinsing liquid to rinsing items that can be arranged in a rinsing container (2) of the dishwasher (1), the method comprising: Drive (S1) the motor (16) of the drive device (15) to actively drive the flushing device (20). The motor speed (SIG) of the motor (16) of the drive unit (15) is detected (S2), and The obstruction of the flushing device (20) is determined (S3) based on the detected motor speed (SIG), wherein the obstruction position of the flushing device (20) is determined, the obstruction position including the rotation angle of the flushing device, wherein an overload protection device (19) is provided between the motor (16) and the flushing device (20), the overload protection device automatically switches from a coupled state to a decoupled state when the flushing device (20) is obstructed, in which force is transmitted between the motor (16) and the flushing device (20), and in the decoupled state... In this configuration, the force transmission between the motor (16) and the rinsing device (20) is disconnected, the drive device (15) is arranged outside the rinsing container (2), wherein an output shaft (17) is provided for transmitting torque from the motor (16) to the rinsing device (20), and an overload protection device (19) is arranged between the output shaft (17) and the rinsing device (20), wherein the overload protection device is designed such that a coupling state can be generated in exactly one specific relative rotational position between the output shaft (17) and the drive shaft (20A) of the rinsing device.

13. The method according to claim 12, characterized in that, The dishwasher in question is a household dishwasher.

14. A computer program product comprising instructions that, when executed by a computer, cause the computer to perform the method according to claim 12 or 13.

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