Device and method for determining bubbles, method for removing bubbles, and kitchen appliance

Abstract

The invention relates to a device for determining the presence or absence of air bubbles in a food product processed by a rotationally driven processing tool, comprising: a power determination device for detecting the power of a driver driving the processing tool; and an evaluation device for determining whether there is a bubble, where the evaluation device detects the bubble based on an output of the power determination device.

Description

Field of the Invention

[0001] The present invention relates to a device for determining the presence of air bubbles in foodstuffs processed by a rotationally driven processing tool. Furthermore, the present invention relates to a kitchen appliance having such a device. The present invention also relates to a method for determining the presence of air bubbles in foodstuffs processed by a rotationally driven processing tool, and to a method for removing such air bubbles. Background Art

[0002] Kitchen appliances such as tabletop blenders are commonly used for food processing in domestic or catering environments. In such appliances, a processing tool (e.g., in the form of a blade that can be rotatably arranged) is rotatably provided within a container and can be driven by an electric motor. By the rotation of the processing tool, the foodstuffs loaded into the container are chopped and mixed.

[0003] During the processing of such tabletop blenders, air bubbles may form around the rotating processing tool. This may be due, for example, to the food being extruded outwards by centrifugal force, causing air to accumulate around the processing tool. The disadvantage of this effect is that the idling processing tool can no longer or can hardly continue to process the food, as it is not in contact with the food or is only in contact to a significantly smaller extent.

[0004] This problem is particularly relevant for highly viscous foodstuffs such as bread spreads, baby food, frozen fruits, nut butters (such as peanut butter), etc. By the rotating processing tool, the food is squeezed to the side, but due to the high viscosity of the food, they do not flow back to the processing tool but remain in a position radially outside the processing tool.

[0005] In order to continue processing the food in such a state, the user can adopt various methods.

[0006] On the one hand, the user can use a pusher tool, which can be used to manually push the food towards the processing tool while the device is running. Such a pusher tool typically looks like a large spoon, a cylindrical rod, or the like. In order to push the food towards the processing tool with such a pusher tool, in many cases, the pusher tool is inserted through an opening in the lid of the container in which the food is located. This method can be used while the electric motor is running, so there is no need to stop the kitchen appliance.

[0007] On the other hand, the rotational speed of the electric motor can be manually reduced by setting a lower rotational speed. After a period of time, the original rotational speed can be reset. At a lower rotational speed, the centrifugal force generated is smaller, which generally causes the immobilized food to flow back to the processing tool, and the air bubbles can also float upwards through the food and thus be removed by the processing tool. Since the food flows back to the processing tool in this way, the processing process can be continued.

[0008] In addition, the household appliance can be switched off, the lid of the container removed, and the food to be processed manually mixed or pressed against the processing tool using a pressing tool. In this way, the bubbles disappear and the food can be re-covered over the processing tool without bubbles. Subsequently, the lid is placed on the container and the household appliance is restarted.

[0009] Each of these steps can be repeated multiple times, which may also depend on the food to be processed. However, the disadvantage is that this method is inconvenient for the user, so an automated method would be advantageous.

[0010] In addition, it would be advantageous for the user if bubbles could be automatically recognized. According to the prior art, whether a user recognizes the presence of bubbles depends on their experience and observation ability. If the user does not recognize the bubbles as bubbles and does not take countermeasures, it will lead to an unsatisfactory processing result. Therefore, it would be advantageous if the recognition of bubbles did not depend on the user. Summary of the Invention

[0011] The present invention is proposed in view of the above disadvantages, and its purpose is to at least partially solve or alleviate these disadvantages.

[0012] The present invention is defined by the independent claims. Preferred embodiments are defined in the corresponding dependent claims.

[0013] According to the present invention, there is provided a device for determining whether there are bubbles in food processed by a rotationally driven processing tool. Here, it is possible to determine whether there are bubbles that interact with the processing tool, in particular surround the processing tool.

[0014] According to an embodiment, the device includes a determination device for determining the operating parameters of the drive. These operating parameters include the power and / or rotational speed of the drive. The inventors have found that bubbles can be detected through these parameters. The device at least determines the instantaneous absorbed power and / or rotational speed of the drive that drives the processing tool. Such a power determination device determines the instantaneous power of the drive that constitutes the drive of the processing tool by simultaneously measuring the applied voltage, the current flowing at present, and taking into account the power factor (cosφ) of the motor.

[0015] In addition, an evaluation device is also provided. The evaluation device determines whether there are bubbles. The evaluation device determines the presence of bubbles at least based on the output of the determination device. Therefore, whether there are bubbles is determined by the operating parameters of the drive. The inventors have found that whether there are bubbles can be determined by the time curve of the drive power. Bubbles are usually accompanied by a significant reduction in the rotational resistance of the processing tool, which is manifested as a sudden drop in the required power. Therefore, whether there are bubbles can be determined by the trend of the power curve. Similarly, bubbles can also be reflected by a sudden increase in rotational speed.

[0016] Preferably, the evaluation device determines the presence of bubbles only when the power drops by more than a certain percentage of the initial power value within a predetermined period. This predetermined amplitude can be a percentage of the maximum instantaneous power of the drive during the processing (i.e., during the process of determining the presence of bubbles). In particular, this predetermined amplitude can be 30% of this maximum value, more preferably 50%, and even possibly 90%. With these features, it is possible to simply determine whether there are bubbles, thus forming a reliable method to reduce the situation of false detection of bubbles.

[0017] Here, it is further preferred that the device includes a rotational speed determination device for determining the rotational speed or number of revolutions of the processing tool. In addition, an evaluation device is also provided here. Generally, when there are bubbles, due to the smaller resistance of the bubbles to the processing tool, the rotational speed will increase. Preferably, the presence of bubbles is determined only when the rotational speed increases by a predetermined amplitude, which is particularly preferably at least 30% before the increase in rotational speed, and more preferably at least 50%.

[0018] It is further preferred that there are a power determination device and a rotational speed determination device, and they are equipped with a common evaluation device. In this case, the selected device determines the presence of bubbles only when the rotational speed increases as the power drops. Therefore, the increase in rotational speed accompanied by the drop in power is a more reliable indicator of the presence of bubbles than simply the drop in power. Therefore, the corresponding device is more reliable. However, this function can also be achieved even if only one of the two determination devices exists.

[0019] It is further preferred that there is a rotational speed adjustment device, which can set the rotational speed target value through the operation interface, and this target value corresponds to the rated value of the adjustment device during normal operation. During the use of the equipment, the adjustment device continuously measures the actual rotational speed of the drive and accordingly adjusts the voltage applied to the drive to keep the actual rotational speed as constant as possible at the rotational speed target value.

[0020] The above-mentioned power determination device, rotational speed determination device, and rotational speed adjustment device are preferably provided together in the equipment. However, each component can also exist in other combinations, which will lead to different characteristics and processes during the bubble identification process:

[0021] Solution 1: There are a rotational speed adjustment device, a power determination device, and a rotational speed determination device.

[0022] The user sets the speed gear or program through the operating device, and this gear or program corresponds internally to the target speed. Under normal circumstances (i.e., when there is no need to remove bubbles), this target speed is consistent with the rated speed of the speed regulating device. Since in this case, the speed regulating device keeps the speed of the driver constant at the rated speed independently of the load, no increase in speed can be recognized when bubbles are present in this configuration. Therefore, in the adjustment system, speed cannot be used for bubble recognition. Instead, as mentioned before, only the power determination device can be used for recognition. It should be noted that in special cases, even with a speed regulating device, the rated speed may not be achievable because the motor does not have the required power. In this case, the speed will increase to the preset rated speed when bubbles appear. However, since this is a special case that only occurs under specific conditions, this increase in speed can be selectively monitored only as a supplement to the above situation. In the subsequent description, this situation will not be further considered.

[0023] Solution 2: There is a power determination device and a speed determination device, but there is no speed regulating device.

[0024] In this solution, the speed gear or program set by the user corresponds internally to the target voltage to be applied to the motor. Under normal circumstances (i.e., when there is no need to remove bubbles), this target voltage corresponds to the actual output voltage, that is, the voltage applied to the driver. According to the characteristic curve of the driver and the existing load, a specific output voltage will generate a specific driver speed. Therefore, bubbles (and the resulting reduction in load) will cause both the speed to increase and the absorbed power to decrease. Therefore, the evaluation device can use these two parameters for bubble recognition, thereby achieving the highest reliability through this method.

[0025] Solution 3: There is only a power determination device.

[0026] In this solution, the speed gear or program set by the user also corresponds internally to the target voltage to be applied to the motor. Under normal circumstances (i.e., when there is no need to remove bubbles), this target voltage corresponds to the actual output voltage, that is, the voltage applied to the driver. According to the characteristic curve of the driver and the existing load, a specific output voltage will generate a specific driver speed. Since the actual speed is not detected, bubbles (and the resulting reduction in load) will cause the absorbed power to decrease, which can be recognized by the evaluation device.

[0027] Solution 4: There is only a speed determination device

[0028] In this solution, the speed setting or program set by the user also corresponds to the target output voltage value of the motor internally. Under normal circumstances (i.e., when there is no need to remove bubbles), this target voltage is the same as the actual output voltage, which is the same as the supply voltage of the driver. According to the characteristic curve of the driver and the load conditions, a specific output voltage will correspond to a specific rotational speed of the driver. The generation of bubbles (and the resulting reduction in load) will cause the rotational speed to increase, and this phenomenon can be detected by the evaluation device.

[0029] To achieve speed regulation, in addition to the method of adjusting the motor output voltage described above, other mechanisms can also be used. For example, some types of motors (such as brushless DC motors) can adjust the rotational speed by changing the output frequency, which is technically equivalent to changing the voltage. For simplicity of expression, only voltage regulation is mentioned below, but its meaning covers frequency changes and is not limited to voltage regulation.

[0030] For the determination of rotational speed, there are various means that can be used as a rotational speed determination device. For example, a Hall effect sensor can be coupled with a magnet or a magnetic ring. In such a device, the rotational speed can be measured by the cooperation of the Hall effect sensor and the magnet: whenever the magnet approaches the sensor, the output signal of the sensor will switch between on and off. By measuring the time interval between these state changes, the rotational speed can be determined based on this.

[0031] Similarly, a combination of a coil and a magnet / magnetic ring can also be used. When the magnet moves near the coil, a voltage will be induced in the coil. Due to the periodic rotation of the magnet, a periodic sine wave can be induced, where the frequency of the signal is inversely proportional to the reciprocal of the rotational speed. The induced voltage can be output as a digital signal through an analog-to-digital converter (Analog-nach-digital-Konverter) or converted into a digital signal through a Schmitt trigger (Schmitt-Trigger).

[0032] In addition, if the driver is a brushless DC motor, sensorless rotational speed measurement can be achieved. The current can be measured on one of the three windings of the driver that is not powered, from which the position of the driver can be determined, and the rotational speed can be obtained through the frequency change of the supply voltage.

[0033] The rotational speed can also be determined by an optical method. This optical rotational speed detection uses an optical detection system, where the transmitting device and the oppositely arranged receiving device work through a light beam. The occlusion of the light beam is used as a state change, based on which the rotational speed can be calculated. There are various implementation methods in this regard: for example, the transmitting device and the receiving device can be located on both sides of a disc with a light-shielding device, and this disc is coupled with the driver. The signal occlusion of the light beam is detected, and the rotational speed is calculated based on this.

[0034] In addition, there is also a reflective sensor, whose transmitting device and receiving device are located in the same housing and arranged side by side. The light is reflected by a mirror or other types of reflecting devices coupled to the driver. Individual light pulses of the reflected light are detected, and the rotational speed is calculated based on this. In addition, a marker can also be provided on the rotating component coupled to the driver, and this marker diffusely reflects the light to the receiving device, thereby counting the pulses and calculating the rotational speed.

[0035] There is also the possibility of measuring the rotational speed based on induction. In this case, the principle of the change in magnetic flux in the sensor is utilized. A simple toothed magnetic rotor is coupled to the driver, and its rotation changes the size of the air gap between the rotor and the sensor, thereby generating a high or low voltage signal. The rotational speed can be determined based on this signal.

[0036] The power can be determined in various ways. For example, the current can be measured. The output of such a sensor is an analog signal proportional to the current flowing in the wire, and of course, this signal can also be digital. In addition, there are direct and indirect methods for measuring this current: for the direct method, the current flows through the integrated sensor circuit; when the sensor measures the current flowing in a nearby wire without itself being connected to the wire, the indirect method is used. A resistor can also be connected in the energized wire, and the voltage drop across this resistor is measured. If the resistance value of this resistor is known and ideally as small as possible, the current flowing through this resistor can be determined according to Ohm's law.

[0037] Particularly preferably, the preset time interval is in the range of 0.05 to 3 seconds, preferably 0.1 to 2 seconds. This enables the rotational speed to increase or the power to decrease to occur relatively quickly. For example, a long-term power decrease caused by a small resistance due to finely chopped food will not result in an incorrect detection of bubbles. At the same time, the upper limit of this range is large enough to cover the time scale in which such bubbles may typically form.

[0038] The above ranges of power decrease, rotational speed increase, and time interval can only be understood as actual example values, because these values depend to a large extent on the performance and form of the kitchen equipment, the processing tools used, and the expected food products (for example, varying by region). Therefore, these values must be determined individually for the specific structural form of the equipment and the target market and cannot be generalized.

[0039] In addition, it is preferable to arrange an output device to indicate the presence of air bubbles. This can be, for example, in the form of a light source, such as a light-emitting diode (LED), which is used to inform the user of the presence of air bubbles. A corresponding indication can also be displayed on a display device (such as a display screen). A sound signal can also be emitted. Other types of signals are also conceivable, especially signals that notify another device (such as a mobile phone or a tablet computer) of the presence of air bubbles via radio. With such an output device, the user can learn of the presence of air bubbles and thus can take measures to remove the air bubbles. It is also conceivable to arrange only an output device for displaying air bubbles on the device, and the device does not itself attempt to remove the air bubbles, that is, only the detection result is displayed, and the removal of the air bubbles is entirely the responsibility of the user.

[0040] According to the invention, there is also provided a kitchen appliance for processing food by means of a processing tool driven in rotation, which has the device as described above. The advantage of such a kitchen appliance is that it facilitates the removal of air bubbles. Such a kitchen appliance can be a tabletop blender. However, many other types of kitchen appliances are also conceivable, such as food processors, stick blenders, egg beaters, dough mixers, hand blenders, etc.

[0041] In this regard, it is preferable that the kitchen appliance is configured to:

[0042] · When the presence of air bubbles is detected, temporarily reduce the target rotational speed of the processing tool from the set target value and then restore the target rotational speed to the target value (applicable to Solution 1 - with rotational speed adjustment)

[0043] Or

[0044] · When the presence of air bubbles is detected, temporarily reduce the output voltage supplied to the drive from the set target voltage and then restore the output voltage to the target voltage (applicable to Solutions 2 - 4 - without rotational speed adjustment).

[0045] The reduction of the rated rotational speed preferably reduces the rated rotational speed by at least 20%, more preferably at least 50%, and even more preferably reduces the rated rotational speed to the minimum possible rotational speed of the system. Here, the rated rotational speed refers to the rotational speed output from the adjustment system of the device to the drive, and the drive should therefore reach this rotational speed. In normal operation, that is, when there is no need to remove air bubbles, this rated rotational speed is consistent with the target rotational speed set by the user. However, during the process of removing air bubbles, the rated rotational speed can be temporarily lower than this target rotational speed. In principle, the processing tool can also be stopped, that is, the drive is briefly switched off, but then the drive should be restarted within a sufficiently short time (for example, 1 second as specified in UL982 Edition 8 §27.13) to prevent the user from thinking that the kitchen appliance has been switched off and touching the processing tool. If the device can detect whether the lid is closed, a longer time may be allowed. In this case, there is no danger for the user to touch the operating device.

[0046] After reducing the rated speed, it is increased again to the target value. Thus, the rated speed is only temporarily reduced. By reducing the rated speed, the centrifugal force acting on the food to be processed is temporarily reduced. For foods with a low enough viscosity, this causes the bubbles to collapse on their own, so that the bubbles can be removed. When this method is automatically executed when bubbles are detected, this improves the processing efficiency and user-friendliness of the kitchen device, because the bubbles that interfere with processing can be automatically removed.

[0047] In this regard, it is preferred that when the evaluation device determines that there are bubbles, the kitchen device is configured to reduce and then increase the rated speed multiple times. By this multiple reduction and increase of the rated speed, it is easier to remove such bubbles.

[0048] In this regard, it is also preferred that when it is determined that the bubbles still exist after a preset number of reductions and increases of the rated speed, the kitchen device emits a signal that the bubbles still exist. This determination that the bubbles still exist can be manifested, for example, by the power of the drive still being lower by a certain percentage (e.g., at least 10%) than the power before the presence of bubbles was detected. This can alert the user that, despite the method of automatically removing bubbles, the bubbles still exist. The user can then remove these bubbles, for example, by means of a pressing device or other suitable means.

[0049] The method described above can be similarly applied to devices without speed regulation (Solutions 2-4). In this case, when bubbles appear, instead of regulating the rated speed, a similar regulation of the output voltage is carried out.

[0050] In an embodiment without a power determination device, it is also possible to determine whether the bubbles still exist by evaluating the rotational speed of the processing tool. For example, after the output voltage has returned to the target voltage, the rotational speed is still lower by a certain percentage (e.g., at least 20%) than the rotational speed before the bubbles were detected.

[0051] Furthermore, there is also claimed a method for determining whether there are bubbles in food processed by a rotationally driven processing tool as described in claim 10. Regarding the features and advantages of this method and the corresponding preferred method claims, reference is made to the device features discussed above. The same applies to the method of using a rotational processing tool to remove bubbles from the food to be processed according to the present invention. Description of the Drawings

[0052] Figure 1 A kitchen device according to the present invention is shown in schematic form.

[0053] Figure 2 A schematic diagram for illustrating bubble detection according to the first embodiment.

[0054] Figure 3 A method for bubble detection according to the second embodiment is shown.

[0055] Figure 4 Shows a successful bubble removal process.

[0056] Figure 5 Shows a failed bubble removal process.

[0057] Figure 6 Shows the bubble detection and removal method of the present invention according to Solution 1 in the form of a flowchart.

[0058] Figure 7 Shows the bubble detection and removal method of the present invention according to Solution 2 in the form of a flowchart.

[0059] Figure 8 Shows the bubble detection and removal method of the present invention according to Solution 3 in the form of a flowchart.

[0060] Figure 9 Shows the bubble detection and removal method of the present invention according to Solution 4 in the form of a flowchart. Detailed implementation

[0061] Figure 1 Shows in schematic form a tabletop blender 100 as an example of a kitchen appliance according to the present invention.

[0062] On the tabletop blender 100, a container 1 is arranged on a housing 5. Inside the container 1 is food 2, which needs to be processed by a processing tool 4 in the form of a rotating blade. The processing tool 4 is driven by a driver 6 arranged inside the housing 5. However, due to the rotation of the processing tool 4, bubbles 3 are formed around the processing tool 4, which hinder the processing of the food 2. The tabletop blender 100 is powered and driven by a power supply 9. At the same time, the rotational speed of the driver 6 (marked as "speed" in the figure) and / or the current flowing into the driver 6 are measured by a corresponding device 7, and thus the real-time power of the driver 6 can be determined. Through a control unit 8 including a rotational speed and / or power evaluation device, the input mains voltage of the power supply 9 can be reduced by a corresponding adjustment device 10 to provide the required output voltage for the driver 5 or the voltage required to reach a specific rated rotational speed. The control unit 8 is also configured to detect the presence of bubbles 3 and take measures to remove them, as described later.

[0063] The basic principle of detecting the presence of bubbles 3 will be described in conjunction with Figure 2 and Figure 3 described.

[0064] In Figure 2 the variation of the rotational speed of the driver and the power of the driver 6 over time can be seen. Figure 2As an example of the implementation of Solution 2, it simultaneously detects rotational speed and power, but there is no rotational speed adjustment device. As shown in the figure, the power drops suddenly from the maximum value corresponding to food processing to near the no-load power within about 1 second, while the rotational speed during food processing rises from a lower value to a second higher value close to the no-load rotational speed. This increase in rotational speed occurs basically simultaneously with the power drop (about 1 second here). The power drop may be caused by bubble formation, which reduces the rotational resistance of the processing tool 4. Therefore, if the control device 8 detects the corresponding changes in the rotational speed and power of the driver 6, it will determine that there are bubbles 3 within the time range marked as the "bubble detection range". The inventor found that such power drops or rotational speed increases usually occur within a time scale of 0.1 to 2 seconds. The exact value of this time scale depends on the volume, structure of the food to be processed, and the form of the equipment structure (i.e., the specific designs of the container 1, the processing tool 4, and the driver 6). Therefore, the time length of the bubble detection range depends especially on the food ingredients to be processed. It should also be noted that here the rotational speed is an average value over time to balance the short-term fluctuations caused by the non-uniformity of the food to be processed.

[0065] Figure 3 A method for constant adjustment of the rotational speed of the processing tool 4 is shown (corresponding to Solution 1; detecting rotational speed and power and there is a rotational speed adjustment device). In this case, bubbles also appear within the "bubble detection range". However, the rotational speed of the driver 6 is basically constant due to adjustment or other reasons. But the power still drops from the maximum value corresponding to food processing to near the no-load power because the resistance of the food is greatly reduced due to bubble formation around the processing tool 4. In this case, the control device 8 also determines that there are bubbles.

[0066] For Solutions 3 and 4 not described, this method applies analogously, only needing to monitor the power curve or the rotational speed curve respectively.

[0067] The control device 8 is also configured to drive the driver 6 to remove the bubbles 4 detected in this way. The corresponding process is shown in Figure 4 and Figure 5 .

[0068] In Figure 4In this case, taking the device of Solution 2 (detecting rotational speed and power but without rotational speed adjustment) as an example, a successful bubble removal cycle is illustrated. Before time t0, there are no bubbles, the rotational speed is the initial value n0, and the power is the initial value P0. At t0, bubbles are formed, the rotational speed rises to a value n1 close to the no-load rotational speed, and the power drops to a value P1 close to the no-load power. During the detection cycle 1 (for example, lasting 1 second) from t0 to t1, a rapid power drop is detected, and at the same time, the rotational speed of the processing tool 4 rises within the same time period. Therefore, the control device 8 determines that there are bubbles 4. Thus, the control device 8 starts to reduce the output voltage from t1, resulting in a decrease in rotational speed, and maintains a low output voltage during the reduction cycle 1 (t1 - t3) for about 2.4 to 4.1 seconds, for example. The typical duration of the reduction cycle is 0.5 to 15 seconds, and multiple short reduction pulses or fewer repeated long reduction pulses can be executed. By reducing the rotational speed, the centrifugal force acting on the food 2 decreases, causing the bubbles 4 to collapse.

[0069] In this example, the bubbles collapse at t2, resulting in an increase in load and further causing a decrease in rotational speed, while the power rises. After the reduction cycle 1 ends at t3, the control device 8 restores the output voltage to the initial value. Subsequently, at t4, it is checked whether the power and rotational speed have returned to the values of n0 and P0 before the appearance of the bubbles 4 at the end of the bubble removal process. In this example, the answer is yes. Since the bubbles 4 have been successfully removed, no further steps are required, and the processing continues normally. However, the control device 8 will continue to monitor the rotational speed and power consumption to detect the generation of new bubbles. The typical duration of such a cycle is about 4 to 20 seconds.

[0070] Figure 5 A failed bubble removal cycle is shown, also taking the Solution 2 embodiment as an example. Here, again at t0, the power suddenly drops from P0 to P1 and is accompanied by an increase in rotational speed from n0 to n1. Therefore, the control device performs a reduction cycle during t1 to t3 as described with reference to Figure 4 and then restores the output voltage to the target voltage. However, in this example, the bubbles do not collapse, and the rotational speed and power do not return to the initial values n0 and P0 but remain at n1 and P1 close to the no-load rotational speed and power. Therefore, another two reduction cycles are performed, during which the output voltage and rotational speed are reduced and then increased again, but in this example, the bubbles still do not collapse. After a preset number of cycles (three cycles here), the control device 8 determines at t7 that this automatic step fails to remove the bubbles 4 and prompts the user that there are bubbles 4 that need to be removed manually.

[0071] Specifically, the method according to the present invention of Solution 1 is shown in Figure 6 . After starting the process in step S100, the control device 8 adjusts and monitors the rotational speed of the processing tool 4 (step S102). Here, setting and monitoring the rotational speed are only used to reduce it to the reduced rotational speed or increase it to the rated rotational speed. Since the rotational speed is constantly adjusted, it is not used for bubble detection. At the same time (step S104), the power of the driver 6 is monitored.

[0072] In a subsequent step, it is checked (step S106) whether food processing is completed. This is the case, for example, when the user manually stops the processing or when the program has finished running. If so (step S106 is "yes"), the process ends (step S120).

[0073] If the food processing is not completed (step S106 is "no"), then as previously combined Figure 2 and Figure 3 as described, it is determined whether there are bubbles (step S108). If there are no bubbles (step S108 is "no"), then the rotation speed is continuously monitored and adjusted as appropriate (step S102). If there are bubbles (step S108 is "yes"), then the rated speed of the driver 4 is reduced (step S110) to cause the bubbles 3 to collapse as described with reference to Figure 4 as described. After a preset time period, the rated speed is increased to the target value (step S112) to resume the required processing flow. Subsequently, it is checked (step S114) whether the power is within the normal range, where the "normal range" means that the power is within the measurement tolerance and the normal fluctuations that occur during the processing, and is consistent with the value before the power change that led to the determination that there are bubbles 3. At the same time, the number of executed cycles is incremented by 1, that is, the number of cycles is increased by 1.

[0074] For the case where the power is within the normal range (step S114 is "yes"), the number of cycles will be reset to 0 (step S116), and then it returns to step S102 to continue monitoring and adjusting the rotation speed because it can be considered that the bubbles 3 have been removed. Conversely, if the rotation speed and / or power are not within the normal range and the number of cycles is less than the threshold (step S114 is "no and the number of cycles is less than the threshold"), then it returns to step S110 to reduce the target rotation speed to attempt to remove the bubbles 3 again.

[0075] If the rotation speed and / or power are not within the normal range and the number of cycles is greater than or equal to the threshold (step S114 is "no and the number of cycles is greater than or equal to the threshold"), then a signal is sent to the user (step S118). Through this signal, the user is informed that there are bubbles and thus can remove them.

[0076] After sending this signal, the rotation speed (step S130) and power (step S132) are continuously monitored. If the processing is finished (step S134 is "yes"), the process ends (step S120). Otherwise (step S134 is "no"), it is checked whether the bubbles still exist (step S136). If they exist (step S136 is "yes"), it jumps to step S118; otherwise (step S136 is "no", that is, the user manually removes the bubbles), it jumps to step S114.

[0077] Figure 7The process of Solution 2 is shown. Here, the rotational speed of the driver is not adjusted, so a voltage corresponding to the user-set speed gear is output to the motor.

[0078] After starting the process in step S100, the control device 8 adjusts the rotational speed of the processing tool 4 (step S102). As described below, the rotational speed will be used together with the power for bubble detection. At the same time (step S104), the power of the driver 6 is monitored.

[0079] Subsequent steps check (step S106) whether food processing is completed. For example, this is the case when the user manually stops processing or the program has finished running. If so (step S106 is "yes"), the process ends (step S120).

[0080] If food processing is not completed (step S106 is "no"), as previously combined with Figure 2 and Figure 3 described, it is determined whether there are bubbles (step S108). If there are no such bubbles (step S108 is "no"), the rotational speed continues to be monitored (step S102). If there are bubbles (step S108 is "yes"), the motor voltage of the driver 4 is reduced (step S110) to cause the bubbles 3 to collapse (as described with reference to Figure 4 ). After a preset time period, the motor voltage is raised to the set value (step S112) to resume the processing flow. Subsequently, it is checked (step S114) whether the rotational speed and power are within the normal range. The normal range is understood here as the rotational speed and power being within the measurement tolerance range and being the same as the values before the change in power and rotational speed that led to the determination of the existence of bubbles 3. At the same time, the number of completed cycles is incremented by 1, that is, the cycle number is increased by 1.

[0081] If the rotational speed and power are within the normal range (step S114 is "yes"), the cycle number is reset to 0 (step S116), and then it returns to step S102 to continue monitoring and adjusting the rotational speed because it can be considered that the bubbles 3 have been removed. Conversely, if the rotational speed and / or power are not within the normal range and the cycle number is less than the threshold (step S114 is "no and the cycle number is less than the threshold"), then it returns to step S110 to reduce the motor voltage to start another attempt to remove the bubbles 3.

[0082] If the rotational speed and / or power are not within the normal range and the cycle number is greater than or equal to the threshold (step S114 is "no and the cycle number is greater than or equal to the threshold"), a signal is sent to the user (step S118). Through this signal, the user is informed that there are bubbles and thus can remove them.

[0083] After sending the signal, continue to monitor the rotational speed (step S130) and power (step S132). If the processing is completed (step S134 is "Yes"), the process ends (step S120). Otherwise (step S134 is "No"), check whether bubbles still exist (step S136). If bubbles exist (step S136 is "Yes"), jump to step S118. Otherwise (step S136 is "No"), jump to step S114.

[0084] Figure 8 Fig. shows the flow according to Solution 3. During this process, the speed of the driver is not measured, but only the power is monitored. Here, the speed level set by the user internally corresponds to the target voltage to be applied to the motor. Usually, that is, when no bubble removal is required, this target voltage corresponds to the actual output voltage, i.e., the voltage applied to the driver. According to the characteristic curve of the driver and the existing load, a specific output voltage will generate a specific speed of the driver.

[0085] After starting the process in step S100, monitor the power of the driver 6 (step S104).

[0086] As a subsequent step, check (step S106) whether the food processing is completed. For example, this is the case when the user manually stops the processing or the program has finished running. If this is the case (step S106 is "Yes"), then the process ends (step S120).

[0087] However, if the food processing has not been completed (step S106 is "No"), then as described above with reference to Figure 2 and Figure 3 determine whether there are bubbles (step S108). If there are no such bubbles (step S108 is "No"), then continue to monitor the power (step S102). However, if there are bubbles (step S108 is "Yes"), then reduce the motor voltage of the driver 4 (step S110) so that the bubble 3 collapses as described with reference to Figure 4 After a certain preset time period, increase the motor voltage to a preset value (step S112) to return to the required processing process. Then check (step S114) whether the power is within the normal range. The "normal range" here means that the power value is within the measurement tolerance range corresponding to the value that existed before the power change that led to the determination of the existence of bubble 3. At the same time, increase the number of completed cycles by 1, that is, increase the cycle number by 1.

[0088] If the power is within the normal range (step S114 is "Yes"), the cycle count is reset to 0 (step S116), and then the process continues to step S104 for monitoring the power, because it can be considered that the bubble 3 has been removed. However, if the power is not within the normal range and at the same time the cycle count is less than the threshold (step S114 is "No" and the cycle count is less than the threshold), then the process enters step S110 to reduce the motor voltage to start attempting to remove the bubble 3 again.

[0089] However, if the power is not within the normal range and at the same time the cycle count is greater than or equal to the threshold (step S114 is "No" and the cycle count is greater than or equal to the threshold), a signal is sent to the user (step S118). Through this signal, the user is informed that there is a bubble and thus it can be removed.

[0090] After sending this signal, the power is continuously monitored (step S132). If the processing is completed at this time (step S134 is "Yes"), the process ends (step S120). Otherwise (step S134 is "No"), it is checked whether the bubble still exists (step S136). If this is the case (step S136 is "Yes"), then it jumps to step S118. Otherwise (step S136 is "No"), it jumps to step S114.

[0091] Figure 9 The flow according to Solution 4 is shown. During this process, the speed of the drive is monitored, but not adjusted, and the power is not monitored. Therefore, a motor voltage corresponding to the speed level set by the user is applied to the drive.

[0092] After step S100 to start this process, the rotational speed of the drive 4 is monitored (step S102). As described below, the rotational speed will be used together with the power for bubble detection. Here, a motor voltage corresponding to the speed level set by the user is applied to the drive.

[0093] As the next step, it is checked (step S106) whether the food processing is completed. For example, this is the case when the user manually stops the processing or the program has finished running. If this is the case (step S106 is "Yes"), the process ends (step S120).

[0094] However, if the food processing has not been completed (step S106 is "No"), then as previously mentioned with reference to Figure 2 and Figure 3 it is determined whether there are bubbles (step S108). If there are no such bubbles (step S108 is "No"), the rotational speed is continuously monitored (step S102). However, if there are bubbles (step S108 is "Yes"), the motor voltage of the drive 4 is reduced (step S110) so that as with reference to Figure 4The bubble 3 is collapsed. After a certain preset time period, the motor voltage is increased to a preset value (step S112) to return to the required machining process. Then, it is checked (step S114) whether the rotational speed is within the normal range. The "normal range" here means that the rotational speed value is within the measurement tolerance range corresponding to the value that existed before the rotational speed change that led to the determination of the existence of the bubble 3. At the same time, the number of completed cycles is incremented by 1, i.e., the cycle number is increased by 1.

[0095] If the rotational speed is within the normal range (step S114 is "Yes"), the cycle number is reset to 0 (step S116), and then the process continues to step S102 for monitoring the rotational speed because it can be considered that the bubble 3 has been removed. However, if the rotational speed is not within the normal range and at the same time the cycle number is less than the threshold (step S114 is "No" and the cycle number is less than the threshold), then the process enters step S110 of reducing the motor voltage to start another attempt to remove the bubble 3.

[0096] But if the rotational speed is not within the normal range and at the same time the cycle number is greater than or equal to the threshold (step S114 is "No" and the cycle number is greater than or equal to the threshold), a signal is sent to the user (step S118). Through this signal, the user is informed that there is a bubble and thus it can be removed.

[0097] After sending this signal, the speed is continuously monitored (step S130). If the machining is completed at this time (step S134 is "Yes"), the process ends (step S120). Otherwise (step S134 is "No"), it is checked whether the bubble still exists (step S136). If this is the case (step S136 is "Yes"), then it jumps to step S118. Otherwise (step S136 is "No"), it jumps to step S114.

Claims

1. An apparatus for determining the presence of air bubbles in food processed by a rotationally driven processing tool, the apparatus having: - Determining means for determining at least one operating parameter of a drive (6) for driving the processing tool (4), - An evaluation device for determining whether there are bubbles (3), wherein, The evaluation means detects air bubbles based on the output of the determination means, wherein the operating parameter includes the power of the drive and / or the rotational speed of the drive.

2. The device according to claim 1, wherein, The evaluation means determines the presence of air bubbles (3) when the power drops by a predetermined amount within a predetermined time period.

3. The apparatus according to claim 2, The device also has a rotational speed determination device for determining the rotational speed of the processing tool (4), wherein, The evaluation means determines the presence of air bubbles (3) based on the determined rotational speed, wherein preferably the presence of air bubbles is determined only when the rotational speed increases by a predetermined amount as the power drops.

4. The device according to claim 2 or 3, wherein, The predetermined time period ranges from 0.05 to 3 seconds, preferably from 0.1 to 2 seconds.

5. The apparatus according to any one of the preceding claims, the apparatus further having output means for outputting the presence of air bubbles (3).

6. A kitchen appliance (100), the kitchen appliance being configured to process food (2) by a rotationally driven processing tool (4), the kitchen appliance having the apparatus according to any one of the preceding claims, the apparatus being provided for determining the presence of air bubbles (3) in the food.

7. The kitchen equipment according to claim 6, wherein, The kitchen appliance (100) is configured to temporarily reduce the supply voltage of the drive of the motor from a target value and then restore the voltage to the target value when it is determined that air bubbles (3) are present; or to temporarily reduce the rated rotational speed of the processing tool (4) from a target value and then restore the rated rotational speed to the target value when it is determined that air bubbles (3) are present.

8. The kitchen equipment according to claim 7, wherein, The kitchen appliance (100) is configured to repeatedly reduce and then increase the rated rotational speed / voltage when the evaluation means determines the presence of air bubbles (3).

9. The kitchen equipment according to claim 7 or 8, wherein, When the kitchen appliance determines that the air bubbles (3) are still present after a preset number of reductions and restorations of the rated rotational speed / voltage, it outputs a signal indicating the presence of the air bubbles (3).

10. The kitchen appliance according to any one of the preceding claims, wherein, The rotational speed is adjustable.

11. A method for determining the presence of air bubbles in food processed by a rotationally driven processing tool, the method comprising the steps of: - Determining at least one operating parameter of a drive (6) for driving the processing tool (4), - Determining the presence of air bubbles (3) based on the determined operating parameter, wherein the operating parameter includes the power of the drive and / or the rotational speed.

12. The method according to claim 11, wherein, The presence of air bubbles (3) is determined only when the power drops by a predetermined amount within a predetermined time period.

13. The method according to claim 12, wherein, Determining the rotational speed of the processing tool (4), wherein the presence of air bubbles (3) is determined only when the rotational speed increases as the power drops.

14. The method according to claim 12 or 13, wherein, The predetermined time period ranges from 0.05 to 3 seconds, preferably from 0.1 to 2 seconds.

15. The method according to any one of claims 11 to 14, the method further comprising the step of outputting the presence of air bubbles (3).

16. A method for removing air bubbles from food processed by a rotational processing tool, the method comprising the following steps: - performing the method according to any one of claims 11 to 15, - when it is determined that there are bubbles (3), temporarily reducing the rated speed of the processing tool (4) starting from the target value, and then restoring the rated speed to the target value, or temporarily reducing the supply voltage of the driver starting from the target value, and then restoring the voltage to the target value.

17. The method according to claim 16, wherein, When it is determined that there are bubbles (3), reducing the rated speed / voltage multiple times and then restoring to the target value.

18. The method according to claim 16 or 17, the method further comprising the steps of: When it is determined that the bubbles (3) still exist after a preset number of reductions and restorations of the rated speed / voltage, output a signal indicating that the bubbles (3) still exist.

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