Electric toothbrush, control method and motor

Abstract

The invention relates to the technical field of electric toothbrushes, and discloses an electric toothbrush, a control method and a motor. When the cogging torque of the motor is greater than a first threshold value, controlling the motor to change from the current speed to a first preset speed; wherein the first preset speed is smaller than the current speed. According to the scheme, the problem that the position precision is difficult to control is solved, the problems that due to the high cogging torque of the motor, the brush head is blocked, not slippery, not smooth, overshoot and the like in the sweeping movement process are solved, the movement slippery degree of the brush head is improved, and then the tooth brushing experience feeling of a user is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electric toothbrushes, for example, to an electric toothbrush, a control method and a motor. Background Art

[0002] At present, electric toothbrushes powered by single-cell lithium batteries mostly use low cogging torque motors. The maximum torque of low cogging torque motors is smaller than that of high cogging torque motors, and cannot meet the requirements of high torque output in some situations. The static torque of high cogging torque motors is relatively high, which can easily cause problems such as difficult to control position accuracy and poor smoothness of movement during complex movements such as sweeping vibration or two-dimensional vibration, which greatly affects the user's brushing experience.

[0003] Therefore, electric toothbrushes powered by a single lithium battery and equipped with a high cogging torque motor are in urgent need of a motion control method to overcome the problem of difficult-to-control position accuracy, improve the smoothness of the motion, and thereby enhance the user's brushing experience. Summary of the invention

[0004] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0005] The embodiments of the present application provide an electric toothbrush, a control method and a motor to overcome the problem of difficult-to-control position accuracy, improve the smoothness of movement, and thereby enhance the user's brushing experience.

[0006] On the one hand, an embodiment of the present application provides an electric toothbrush, comprising:

[0007] a brush head having a bristle portion at a distal end thereof;

[0008] a handle removably connected to the brush head;

[0009] a motor disposed at least partially within the handle, the motor being configured to generate a periodic motion, the motor comprising:

[0010] a stationary component and a rotating component extending along a first axis, the rotating component being rotatably mounted on the stationary component, the stationary component at least partially surrounding the rotating component;

[0011] The rotating assembly includes a motor shaft, the motor shaft is at least partially contained within the handle and is configured to engage the brush head; the motor shaft is configured to transmit the generated periodic motion to the brush head so that the brush head rotates periodically in a first direction;

[0012] A control unit electrically connected to the motor, the control unit being configured to utilize the cogging torque information to control the motor to change from a current speed to a first preset speed when the cogging torque is greater than a first threshold; wherein the first preset speed is less than the current speed.

[0013] On the other hand, an embodiment of the present application provides an electric toothbrush control method, comprising:

[0014] Obtaining a trigger instruction, wherein the trigger instruction is used to instruct the motor of the electric toothbrush to perform movement;

[0015] In response to the trigger instruction, controlling the motor to rotate periodically in a first direction;

[0016] Obtaining the cogging torque of the motor;

[0017] When the cogging torque is greater than a first threshold, the motor is controlled to change from a current speed to a first preset speed; wherein the first preset speed is less than the current speed.

[0018] On the other hand, an embodiment of the present application provides a motor applied to an electric toothbrush, wherein the motor is configured to generate a periodic motion, including:

[0019] A driving body and a motion detection component, wherein:

[0020] The driving body extending along the first axis includes a stationary component and a rotating component, the rotating component is rotatably mounted on the stationary component, the stationary component at least partially surrounds the rotating component, the stationary component is formed with a receiving chamber, and at least one end of the rotating component extends along the first axis and protrudes to the outside of the stationary component;

[0021] The motion detection component at least partially located in the accommodating chamber includes a Hall sensor and a motion feedback component, wherein the motion feedback component is connected to the rotating component and rotates with the rotating component, the Hall sensor is directly connected to the stationary component, and the Hall sensor detects the motion position of the rotating component through the motion feedback component;

[0022] The rotating component includes a motor shaft, which rotates periodically in a first direction. The motor is configured to control the motor to change from a current speed to a first preset speed when the cogging torque of the motor is greater than a first threshold; wherein the first preset speed is less than the current speed.

[0023] The various technical solutions provided in the embodiments of the present application, in the scenario of an electric toothbrush powered by a single lithium battery and equipped with a high cogging torque motor, reduce the rate of change of the cogging torque by reducing the current speed of the motor when the cogging torque is large, so that the electric toothbrush has sufficient response time to overcome the disturbance caused by the sudden change of the high cogging torque, thereby stabilizing the servo control and overcoming the problem of difficult control of position accuracy, avoiding the problems of jamming, non-smoothness, unevenness, overshooting, etc. of the brush head during the sweeping motion caused by the high cogging torque of the motor itself, improving the smoothness of the brush head movement, and thereby improving the user's brushing experience.

[0024] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] One or more embodiments are exemplarily described by corresponding drawings, and these exemplary descriptions and drawings do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are considered similar elements, and the drawings do not constitute a scale limitation, and wherein:

[0026] Figure 1 is a schematic diagram of an electric toothbrush provided in Example 1 of the present application;

[0027] Figure 2 This is a schematic diagram of the relationship between the motor shaft motion angle and the cogging torque of a motor provided in Example 1 of the present application;

[0028] Figure 3 is a cross-sectional view of a motor provided in Example 1 of the present application;

[0029] Figure 4 is another cross-sectional view of a motor provided in Embodiment 1 of the present application;

[0030] Figure 5 is a flow chart of a control method of an electric toothbrush provided in Embodiment 2 of the present application;

[0031] Figure 6 It is a structural schematic diagram of a control device for an electric toothbrush provided in Embodiment 3 of the present application;

[0032] Figure 7 It is a schematic diagram of the structure of an electronic device that implements the control method of the electric toothbrush of an embodiment of the present application. DETAILED DESCRIPTION

[0033] The motor in this solution can be a permanent magnet motor. Cogging torque is a torque pulsation phenomenon unique to permanent magnet motors. When the rotating component of the permanent magnet motor rotates, due to the presence of stator slots, the magnetic field energy between the permanent magnet and the stator slots changes periodically, thereby generating a periodic torque fluctuation, which is the cogging torque. In this solution, a low cogging torque motor refers to a motor whose cogging torque is always less than 4.5mN.M; a high cogging torque motor refers to a motor whose cogging torque is greater than 4.5mN.M.

[0034] To achieve precise position control, part of the motor's output torque is needed to offset the cogging torque, thereby eliminating the influence of the cogging torque. The rated output torque of the motor is proportional to the supply voltage. Therefore, in the control scenario of an electric toothbrush powered by a single lithium battery or an equivalent voltage and equipped with a high cogging torque motor, especially for complex motion processes such as sweeping vibration or two-dimensional vibration, the supply voltage is small and the rated output torque of the motor is also small. When the cogging torque is large and the cogging torque change rate is fast, it is easy for the motor to not have enough output torque to eliminate the influence of the cogging torque, which makes it difficult to control the position accuracy and the smoothness of the movement is poor, which greatly affects the user's brushing experience.

[0035] In order to solve the above-mentioned technical problems, in the solution provided by the present application, in the scenario of an electric toothbrush powered by a single lithium battery and equipped with a high cogging torque motor, the rate of change of the cogging torque is reduced by reducing the current speed of the motor when the cogging torque is large, so that the electric toothbrush has sufficient response time to overcome the disturbance caused by the sudden change of the high cogging torque, thereby stabilizing the servo control and overcoming the problem of difficult control of position accuracy. It avoids the problems of stuttering, non-smoothness, unevenness, overshoot, etc. of the brush head during the sweeping motion caused by the high cogging torque of the motor itself, improves the smoothness of the brush head movement, and thereby improves the user's brushing experience.

[0036] The terms "target", "first", "second", etc. in the description, claims, and drawings of the embodiments of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so as to describe the embodiments of the embodiments of the present application described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0037] Unless otherwise indicated, the term "plurality" means two or more. The term "plurality" means two or more.

[0038] In the embodiment of the present application, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B.

[0039] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0040] The term "correspondence" may refer to an association relationship or a binding relationship. The correspondence between A and B means that there is an association relationship or a binding relationship between A and B.

[0041] In order to be able to understand the features and technical contents of the embodiments of the present application in more detail, the implementation of the embodiments of the present application is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present application. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0042] Embodiment 1

[0043] Figure 1 This is a schematic diagram of an electric toothbrush provided in Example 1 of the present application. This embodiment can be applied to electric toothbrush control scenarios based on a single lithium battery or an equivalent voltage power supply and equipped with a high cogging torque motor. Normally, the nominal voltage of a single lithium battery is generally 3.7V, and its full-charge voltage can reach up to 4.2V. The termination voltage, that is, the voltage at the end of discharge, is usually around 3.3V.

[0044] like Figure 1 As shown, the electric toothbrush comprises:

[0045] a brush head having a bristle portion at a distal end thereof;

[0046] a handle removably connected to the brush head;

[0047] A motor, the motor being at least partially disposed within the handle, the motor being configured to generate a periodic motion, the motor comprising:

[0048] A stationary component and a rotating component extending along a first axis, wherein the rotating component is rotatably mounted on the stationary component and the stationary component at least partially surrounds the rotating component;

[0049] The rotating assembly includes a motor shaft, the motor shaft is at least partially contained within the handle and is configured to engage the brush head; the motor shaft is configured to transmit the generated periodic motion to the brush head so that the brush head rotates periodically in a first direction;

[0050] A control unit electrically connected to the motor, the control unit being configured to utilize the cogging torque information to control the motor to change from a current speed to a first preset speed when the cogging torque is greater than a first threshold; wherein the first preset speed is less than the current speed.

[0051] The first axis may be a central axis of the motor shaft.

[0052] The first preset speed is a speed preset based on experience.

[0053] During implementation, when the cogging torque is equal to the first threshold, if the current speed is greater than the first preset speed, the motor can be controlled to change from the current speed to the first preset speed; if the current speed is equal to or less than the first preset speed, the motor can still be controlled to maintain the current speed, and this solution does not impose any restrictions.

[0054] The first direction refers to a direction around the central axis of the electric toothbrush, wherein the central axis of the electric toothbrush may be parallel to or overlap with the central axis of the motor shaft.

[0055] It is understandable that the motor can drive the brush head to perform a composite motion such as sweeping vibration or two-dimensional vibration in the first direction. For example, when the electric toothbrush is performing a sweeping vibration motion, the motor drives the brush head to vibrate at a high frequency and then rapidly reciprocate within a certain angle range, similar to a "sweeping" motion. The speed of this reciprocating swing at the current moment can be used as the current speed of the motor.

[0056] Specifically, the motor in this solution can be a servo motor. The torque sensor installed on the motor can be used to measure the torque transmitted by the motor shaft in real time to obtain the motor torque, which of course includes the cogging torque. The torque sensor works based on different physical mechanisms such as the strain gauge principle and the magnetoelastic principle. For example, when the motor shaft transmits torque and produces torsional deformation, the resistance of the strain gauge attached to the shaft will change. By measuring the resistance change and converting and calibrating the corresponding circuit, the torque value of the motor torque can be accurately obtained, and then the cogging torque can be analyzed to obtain the cogging torque information. The cogging torque information includes the cogging torque of the motor.

[0057] Specifically, the current speed of the motor can be measured by using a Hall sensor installed on the motor. The Hall sensor is based on the Hall effect. When a magnetic component rotates near it, it will cause a change in the magnetic field. The Hall sensor can convert this magnetic field change into an electrical signal change. By analyzing the frequency, phase and amplitude of the electrical signal and the predetermined corresponding relationship with the rotation speed, the current speed of the motor can be obtained.

[0058] Based on experimental tests, we found that the cogging torque of the motor has a certain periodic correlation with the position of the rotating component. The position of the rotating component can be represented by the motor shaft movement angle of the motor, that is, the cogging torque of the motor has a certain periodic correlation with the motor shaft movement angle. This periodic correlation can be found in Figure 2 As shown in the figure below. Figure 2 In the figure, when the motor shaft movement angle is angle 0, it corresponds to the valley of the cogging torque, and angles 1 and 2 correspond to the peaks of the cogging torque respectively. V1 represents the current speed of the motor, and V2 represents the first preset speed. The cogging torque in the figure is a scalar curve, which only represents the size, not the direction. The cogging torque corresponding to the valley of the waveform is zero. A sub-waveform is formed between two adjacent valleys. Under ideal conditions, the shape of each sub-waveform is the same. Therefore, when the cogging torque is greater than the first threshold, that is, the cogging torque is large, if the current speed of the motor is also large, that is, the rate of change of the motor shaft movement angle of the motor is large, it is easy to cause a large rate of change of the cogging torque. The motor in this scheme can be a 4-pole 6-slot motor, refer to Figure 3 , provides the motor cross-section diagram corresponding to the motor shaft movement angle of angle 0, at which time the motor's cogging torque is at the valley value, that is, the cogging torque is minimum. Figure 4 , provides the motor cross-section diagram corresponding to the motor shaft movement angle of angle 1, at which time the motor's cogging torque is at its peak value, that is, the cogging torque is maximum. Figure 3 and Figure 4 As shown, the motor includes a stationary component and a rotating component. The stationary component includes a winding and a stator core. The rotating component includes a motor shaft, a magnet and a rotor core.

[0059] During implementation, a photoelectric encoder, a magnetic encoder or the motor's own magnetic field sensor combined with an algorithm can be used to indirectly infer the angle and monitor the motor shaft movement angle in real time.

[0060] The technical solution provided in the embodiment of the present application, in the scenario of an electric toothbrush powered by a single lithium battery and equipped with a high cogging torque motor, reduces the rate of change of the cogging torque by reducing the current speed of the motor when the cogging torque is large, so that the electric toothbrush has sufficient response time to overcome the disturbance caused by the sudden change of the high cogging torque, thereby stabilizing the servo control and overcoming the problem of difficult control of position accuracy, avoiding the problems of jamming, non-smoothness, unevenness, overshooting, etc. of the brush head during the sweeping motion caused by the high cogging torque of the motor itself, improving the smoothness of the brush head movement, and thereby improving the user's brushing experience.

[0061] In one achievable manner, the control unit is configured to control the motor to change from the current speed to a second preset speed when the cogging torque is less than a first threshold; wherein the second preset speed is greater than the current speed.

[0062] It can be understood that in order to ensure the user's brushing experience, when the tooth groove torque is less than the first threshold, the motor speed can be controlled to increase the previously reduced speed again.

[0063] In one possible implementation, the cogging torque of the motor has a maximum value Tsmax, Tsmax≥4.5 mN.M. A high cogging torque motor is used in an electric toothbrush, and its maximum torque is larger than that of a low cogging torque motor, and can meet the requirement of high torque output in some occasions.

[0064] In one implementable embodiment, the control unit is configured to control the rotation speed of the motor from a first speed to a second speed when the cogging torque is greater than a first threshold value; and to control the rotation speed of the motor from the second speed to a third speed when the cogging torque is greater than a second threshold value, wherein the first threshold value is less than the second threshold value, the first speed is greater than the second speed, and the second speed is greater than the third speed.

[0065] It can be understood that in order to further improve the smoothness of the brush head movement, two thresholds corresponding to the cogging torque, namely the first threshold and the second threshold, can be set to control the rotation speed of the motor for speed change. Similarly, more than two thresholds corresponding to the cogging torque can be set to control the rotation speed of the motor for speed change.

[0066] In one implementable manner, obtaining the cogging torque includes obtaining a first operating parameter of the motor, and determining the cogging torque based on a mapping relationship between the cogging torque and the first operating parameter, wherein the first operating parameter is at least one of a motor shaft movement angle, a motor current, and a motor torque.

[0067] Since the motor shaft movement angle is easy to obtain with high accuracy, determining the cogging torque based on the mapping relationship between the cogging torque and the motor shaft movement angle is easy to implement and has high accuracy.

[0068] Since the motor current is easy to obtain, it is easy to determine the cogging torque based on the mapping relationship between the cogging torque and the motor current, which is easy to implement.

[0069] The cogging torque can be easily determined by using the mapping relationship between the motor torque and the cogging torque.

[0070] In one achievable manner, the periodic rotation includes a first cleaning motion or a second cleaning motion, a rotation angle of the first cleaning motion is different from a rotation angle of the second cleaning motion, and the electric toothbrush performs the first cleaning motion while performing the second cleaning motion.

[0071] During implementation, the electric toothbrush can perform a sweeping and vibrating integrated motion. Among them, the first cleaning motion can be a sweeping motion, and the second cleaning motion can be a vibration. At this time, the rotation angle of the first cleaning motion is used to characterize the sweeping amplitude of each sweep of the first cleaning motion. The rotation angle of the second cleaning motion is used to characterize the vibration amplitude of each vibration of the second cleaning motion. Alternatively, the first cleaning motion is a vibration, and the second cleaning motion is a sweeping motion. At this time, the rotation angle of the first cleaning motion is used to characterize the vibration amplitude of each sweep vibration of the first cleaning motion. The rotation angle of the second cleaning motion is used to characterize the sweeping amplitude of each sweep of the second cleaning motion.

[0072] In an implementable manner, the motor shaft is further configured to transmit the generated periodic motion to the brush head, so that the brush head moves periodically in a second direction, and the second direction is parallel to the central axis of the electric toothbrush.

[0073] The central axis of the electric toothbrush can be parallel to or overlap with the central axis of the motor shaft.

[0074] During implementation, a bidirectional servo motor can be used to achieve not only circumferential reciprocating rotation such as sweeping and vibration, but also axial reciprocating movement to enhance the user's brushing experience.

[0075] In an implementable manner, the motor shaft is further configured to transmit the generated periodic motion to the brush head, so that the brush head moves periodically in a third direction, which is perpendicular to the central axis of the electric toothbrush.

[0076] During implementation, a multi-directional servo motor can be used to realize not only circumferential reciprocating rotation such as sweeping and vibration, and axial reciprocating movement, but also compound tapping motion to enhance the user's brushing experience.

[0077] In one implementation, the handle further comprises a user interaction component, and the motor is configured such that when the bristle portion of the brush head connected to the motor shaft faces the same direction as the user interaction component, the cogging torque is zero or has a minimum value.

[0078] Among them, the user interaction components may include buttons, indicator lights, and display screens, etc.

[0079] In actual scenarios, the minimum value of the motor's cogging torque may be equal to zero or greater than zero.

[0080] By setting the cogging torque to zero or the minimum value when the bristle part of the brush head connected to the motor shaft and the user interaction component are facing the same direction, it is helpful to ensure the user's brushing experience. When using an electric toothbrush, the user usually faces the side where the user interaction components such as buttons are located to start or select gears, and then puts the electric toothbrush into the mouth to start the cleaning movement; setting the bristle part of the brush head and the user interaction component to face the same direction, that is, both facing the user, is convenient for the user to judge the position of the bristle part at the beginning of the cleaning movement, and put it into the mouth to start the cleaning operation, which is in line with the user's usage habits.

[0081] The yaw of an electric toothbrush after power failure means that after the electric toothbrush stops supplying power, such as when the power is turned off or the battery is exhausted, the brush head cannot remain in a stable static state, but instead swings left and right or up and down. Under normal circumstances, the brush head should remain in a stable position after the electric toothbrush is powered off, just like a normal toothbrush placed there. The yaw of an electric toothbrush after power failure can easily affect the life of the electric toothbrush and the user's brushing experience.

[0082] Normally, any of the following situations may cause the electric toothbrush to swing after power is turned off: incorrect installation of the brush head, loose connection between the brush head and the handle, the motor not working properly, the motor shaft is damaged or loose, the battery power is insufficient, or the power supply contact is poor. In the related art, the problem of electric toothbrush swing is eliminated by checking whether the brush head is installed correctly, whether the brush head and the brush handle are tightly connected, whether the motor is working properly, whether the motor shaft is damaged or loose, whether the battery power is sufficient, and whether the power supply contact is good. However, even if the brush head is installed normally, the brush head and the brush handle are tightly connected, the motor is working properly, the motor is working properly, the motor shaft is not damaged or loose, the battery power is sufficient, and the power supply contact is good, the problem of electric toothbrush swinging after power is turned off may still exist.

[0083] In order to ensure the user's brushing experience, the position of the motor shaft in which the bristle part of the brush head connected to the motor shaft and the user interaction component are facing the same direction is usually used as the default power-on position, default power-off position, and initial position of the motor shaft in the electric toothbrush. The position where the cogging torque is zero or the position where the cogging torque has the smallest value is the self-balancing position of the motor. If the power-on default position, the power-off default position, and the initial position of the motor shaft do not correspond to the self-balancing position of the motor, it is very easy to cause the electric toothbrush to swing after power is turned off. Therefore, this solution configures the motor so that when the bristle part of the brush head connected to the motor shaft and the user interaction component face the same direction, the cogging torque of the motor is zero or the cogging torque has the smallest value, which can further eliminate the problem of the electric toothbrush swinging after power is turned off. In addition, the electric toothbrush can have a nearly symmetrical trend of motion resistance change when it rotates after power is turned on, which is beneficial to the motion control of the electric toothbrush.

[0084] In implementation, this solution controls the motor to change from the current speed to the preset speed when the cogging torque is greater than the first threshold, wherein the first preset speed is less than the current speed; and the motor is configured such that when the bristle portion of the brush head connected to the motor shaft is in the same direction as the user interaction component, the cogging torque is zero or the value of the cogging torque is minimum, so that the motor shaft of the motor can be fast in the middle and slow at the boundary, meeting the cleaning requirements. The "middle" here refers to the initial position close to the motor shaft. The "boundary" here refers to the initial position far from the motor shaft. Reference Figure 2 In the above figure, the angle 0 can be used as the initial position of the motor shaft, corresponding to the state when the motor shaft is in the middle. It can be understood that during the oral cleaning operation, the boundary of one side is closer to the gums than the middle, and the boundary close to the gums changes with the change of the cleaning position, so that the motor shaft of the motor is fast in the middle and slow at the boundary, that is, the cleaning speed close to the gums is slow to avoid damaging the gums, while the cleaning speed of the tooth surface is fast to ensure the cleaning effect.

[0085] In one implementable embodiment, the periodic rotation includes controlling the motor shaft to rotate in a first direction or a second direction with a first axis as the rotation center line relative to the initial position of the motor shaft to drive the brush head to rotate periodically, the first axis is parallel to or overlaps with the axis of the motor shaft, and when the motor shaft is in the initial position, the cogging torque is zero or the cogging torque is minimized.

[0086] refer to Figure 2 In the figure above, the angle 0 can be used as the initial position of the motor shaft. This initial position refers to the position where the electric toothbrush starts to move.

[0087] In implementation, when the motor shaft is in the initial position, the cogging torque is zero or the value of the cogging torque is minimum, which is beneficial to the control of the periodic operation of the brush head.

[0088] Furthermore, the position where the cogging torque is zero or the position where the cogging torque has the minimum value is the self-balancing position of the motor. If the initial position of the motor shaft does not correspond to the self-balancing position of the motor, it is very easy to cause the electric toothbrush to swing after power is turned off. Therefore, this solution helps to avoid the problem of the electric toothbrush swinging after power is turned off by making the cogging torque zero or the cogging torque have the minimum value when the motor shaft is in the initial position.

[0089] In one achievable manner, before it is determined that the periodic motion is performed, the motor shaft is in an initial position; and / or, after it is determined that the periodic motion is completed, the motor shaft is in the initial position.

[0090] In implementation, the initial position of the motor shaft can be used as a power-on default position of the motor shaft, or can be used as a power-off default position of the motor shaft.

[0091] It can be understood that the position where the cogging torque is zero or the position where the cogging torque has the minimum value is the self-balancing position of the motor. If the power-on default position and the power-off default position do not correspond to the self-balancing position of the motor, it is very easy to cause the electric toothbrush to swing after power is turned off. Therefore, ensuring that the cogging torque is zero or the cogging torque has the minimum value when the motor shaft is in the initial position helps avoid the problem of the electric toothbrush swinging after power is turned off.

[0092] In one achievable manner, when the motor shaft is in the initial position, the bristle portion of the brush head and the user interaction component in the grip portion face the same direction.

[0093] It can be understood that when the motor shaft is in the initial position, the bristle portion of the brush head and the user interaction component in the grip portion are oriented in the same direction, which can improve the user's brushing experience.

[0094] In one possible implementation, the periodic rotation has a preset angle, and the initial position of the motor shaft is located at the center of the preset angle.

[0095] In practice, the periodic motion is performed within a preset angle. Figure 2 In the figure above, angle 0 can be used as the initial position of the motor shaft. One cycle of the electric toothbrush movement may include: sweeping from angle 0 to angle 1, then sweeping from angle 1 back to angle 0, then sweeping from angle 0 to angle 2, and finally sweeping from angle 2 back to angle 0. Among them, angle 1 to angle 2 can be used as the preset angle.

[0096] In real time, the initial position of the motor shaft is at the center of the preset angle, which is conducive to the control of periodic operation.

[0097] In one implementable manner, when the cogging torque tends to increase and reaches a third threshold, and the current speed of the motor is greater than a first preset speed, a first speed change rate is determined based on the third threshold, the first threshold and the current speed; wherein the third threshold is less than the first threshold; based on the first speed change rate and the current speed, the motor is controlled to slow down until the cogging torque of the motor reaches the first threshold, and the current speed of the motor drops to the first preset speed; when the cogging torque is greater than the first threshold, the motor is controlled to rotate at the first preset speed.

[0098] In implementation, the target time required to change from the third threshold to the first threshold can be determined based on the current speed of the motor, and then the first speed change rate required to change from the current speed to the first preset speed can be determined based on the target time. Thus, the current speed is adjusted based on the first speed change rate to control the rotation of the motor.

[0099] Considering that when the cogging torque reaches the third threshold and the current speed of the motor is greater than the first preset speed, immediately reducing the current speed to the first preset speed may easily cause large speed fluctuations, resulting in a poor brushing experience for the user. Therefore, this solution can reduce the current speed in advance when the cogging torque has not reached the first threshold to overcome the problem of large speed fluctuations. In the above manner, when the cogging torque reaches the third threshold, the current speed can be reduced, and when the cogging torque reaches the first threshold, the current speed just drops to the first preset speed, thereby conveniently overcoming the problem of large speed fluctuations and improving the user's brushing experience.

[0100] In one implementable manner, when the cogging torque is greater than a first threshold, a second speed change rate is determined based on the cogging torque, and a first preset speed is determined based on the second speed change rate and a preset basic speed value.

[0101] It is understandable that the first preset speed can be a value that changes with time. Through the above method, it can be conveniently realized that when the cogging torque is greater than the first threshold, the greater the cogging torque, the smaller the first preset speed, so that the motor can output sufficient torque as much as possible while ensuring the control accuracy.

[0102] In one achievable manner, the current in the motor is acquired, and the motor shaft movement angle corresponding to the current valley value is taken as the point where the cogging torque is zero.

[0103] Based on experimental tests, we found that the motor shaft movement angle corresponding to the motor current valley is the point where the cogging torque is zero. It can be understood that the point where the cogging torque is zero can be easily determined by the current.

[0104] Embodiment 2

[0105] Figure 5 1 is a flow chart of a control method for an electric toothbrush provided in Example 2 of the present application. Figure 5 As shown, the method includes:

[0106] Step 501, obtaining a trigger instruction, where the trigger instruction is used to instruct the motor of the electric toothbrush to perform movement.

[0107] Step 502: In response to a trigger instruction, control the motor to rotate periodically in a first direction.

[0108] Step 503, obtaining the cogging torque of the motor.

[0109] Step 504, when the cogging torque is greater than the first threshold, control the motor to change from the current speed to a first preset speed; wherein the first preset speed is less than the current speed.

[0110] For the specific implementation and beneficial effects of the electric toothbrush control method, please refer to the description of the electric toothbrush in Example 1 and will not be repeated here.

[0111] Embodiment 3

[0112] Figure 6 Schematic diagram of the structure of a control device for an electric toothbrush provided in Example 3 of the present application. Figure 6 As shown, the device 600 includes:

[0113] The acquisition unit 610 is used to acquire a trigger instruction, where the trigger instruction is used to instruct the motor of the electric toothbrush to perform movement.

[0114] The response unit 620 is used to control the motor to rotate periodically in a first direction in response to the trigger instruction.

[0115] The acquisition unit 610 is further used to acquire the cogging torque of the motor.

[0116] The control unit 630 is used to control the motor to change from the current speed to the first preset speed when the cogging torque is greater than the first threshold; wherein the first preset speed is less than the current speed.

[0117] The control device of the electric toothbrush provided in the embodiment of the present application can execute the control method of the electric toothbrush provided in any embodiment of the present application, and has the corresponding functional modules and beneficial effects for executing the control method of the electric toothbrush.

[0118] The present application also provides a motor, which is applied to an electric toothbrush. The motor is configured to generate a periodic motion, including:

[0119] A driving body and a motion detection component, wherein:

[0120] The driving body extending along the first axis includes a stationary component and a rotating component, the rotating component is rotatably mounted on the stationary component, the stationary component at least partially surrounds the rotating component, the stationary component is formed with a receiving chamber, at least one end of the rotating component extends along the first axis and extends out of the stationary component, and the first axis is parallel to or overlaps with the central axis of the motor;

[0121] The motion detection component at least partially located in the accommodating chamber includes a Hall sensor and a motion feedback component, wherein the motion feedback component is connected to the rotating component and rotates with the rotating component, the Hall sensor is directly connected to the stationary component, and the Hall sensor detects the motion position of the rotating component through the motion feedback component;

[0122] The rotating component includes a motor shaft, which rotates periodically in a first direction, that is, the motor shaft rotates circumferentially with a first axis as a rotation center line. The motor is configured to control the motor to change from a current speed to a first preset speed when the cogging torque of the motor is greater than a first threshold; wherein the first preset speed is less than the current speed, and the first direction is a direction around the first axis.

[0123] In one implementation, the motor shaft has an axial passage, and a fluid inlet and a fluid outlet communicating with the axial passage.

[0124] It can be understood that the motor shaft has an axial channel, so that it can not only transmit power but also be used as a flow channel for fluid to transmit the fluid to the brush head, thereby realizing mechanical transmission of the device with both flushing and brushing functions.

[0125] The corresponding functional modules and beneficial effects of the control method of the electric toothbrush herein can be found in the above embodiments and will not be described in detail here.

[0126] Embodiment 4

[0127] Figure 7 A schematic diagram of the structure of an electronic device 10 that can be used to implement an embodiment of the present application is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present application described and / or required herein.

[0128] like Figure 7 As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0129] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0130] The processor 11 may be a variety of general and / or dedicated processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a control method for an electric toothbrush.

[0131] In some embodiments, any of the above-described control methods for electric toothbrushes may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of any of the above-described control methods for electric toothbrushes may be performed. Alternatively, in other embodiments, the processor 11 may be configured to perform any of the above-described control methods for electric toothbrushes in any other appropriate manner (e.g., by means of firmware).

[0132] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0133] The computer programs for implementing the methods of the present application may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer programs are executed by the processor, the functions / operations specified in the flow charts and / or block diagrams are implemented. The computer programs may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0134] In the context of the present application, a computer readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, device or equipment. A computer readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer readable storage medium may be a machine readable signal medium. A more specific example of a machine readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0135] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0136] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0137] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The relationship between the client and the server is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and virtual private servers (VPS).

[0138] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this application can be executed in parallel, sequentially or in different orders, as long as the expected results of the technical solution of this application can be achieved, and this document is not limited here.

[0139] The above specific implementations do not constitute a limitation on the protection scope of this application. It should be understood by those skilled in the art that various modifications, combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of this application should be included in the protection scope of this application.

Claims

1. An electric toothbrush, characterized in that: include: a brush head having a bristle portion at a distal end thereof; a handle removably connected to the brush head; a motor disposed at least partially within the handle, the motor being configured to generate a periodic motion, the motor comprising: a stationary component and a rotating component extending along a first axis, the rotating component being rotatably mounted on the stationary component, the stationary component at least partially surrounding the rotating component; The rotating assembly includes a motor shaft, the motor shaft is at least partially contained within the handle and is configured to engage the brush head; the motor shaft is configured to transmit the generated periodic motion to the brush head so that the brush head rotates periodically in a first direction; A control unit electrically connected to the motor, the control unit being configured to utilize the cogging torque information to control the motor to change from a current speed to a first preset speed when the cogging torque is greater than a first threshold; wherein the first preset speed is less than the current speed.

2. The electric toothbrush according to claim 1, characterized in that: The control unit is configured to control the motor to change from the current speed to a second preset speed when the cogging torque is less than the first threshold; wherein the second preset speed is greater than the current speed.

3. The electric toothbrush according to claim 1, characterized in that: The cogging torque of the motor has a maximum value Tsmax, and Tsmax≥4.5mN.M.

4. The electric toothbrush according to claim 1, characterized in that: The control unit is configured to control the rotation speed of the motor from a first speed to a second speed when the cogging torque is greater than the first threshold; and to control the rotation speed of the motor from the second speed to a third speed when the cogging torque is greater than the second threshold, wherein the first threshold is less than the second threshold, the first speed is greater than the second speed, and the second speed is greater than the third speed.

5. The electric toothbrush according to claim 1, characterized in that: Obtaining the cogging torque includes obtaining a first operating parameter of the motor, and determining the cogging torque according to a mapping relationship between the cogging torque and the first operating parameter, wherein the first operating parameter is at least one of a motor shaft movement angle, a motor current, and a motor torque.

6. The electric toothbrush according to claim 1, characterized in that: The periodic rotation includes a first cleaning motion or a second cleaning motion, the rotation angle of the first cleaning motion is different from the rotation angle of the second cleaning motion, and the electric toothbrush performs the first cleaning motion and the second cleaning motion simultaneously.

7. The electric toothbrush according to claim 1, characterized in that: The motor shaft is further configured to transmit the generated periodic motion to the brush head, so that the brush head moves periodically in a second direction, which is parallel to the central axis of the motor shaft.

8. The electric toothbrush according to claim 1, characterized in that: The motor shaft is further configured to transmit the generated periodic motion to the brush head, so that the brush head moves periodically in a third direction, which is perpendicular to a central axis of the motor shaft.

9. The electric toothbrush according to claim 1, characterized in that: The handle further comprises a user interaction component, and the motor is configured such that when a bristle portion of a brush head connected to a motor shaft faces the same direction as the user interaction component, the cogging torque is zero or has a minimum value.

10. The electric toothbrush according to claim 1, characterized in that: The periodic rotation includes controlling the motor shaft to rotate along a first direction or a second direction with a first axis as a rotation center line relative to an initial position of the motor shaft, so as to drive the brush head to rotate periodically, wherein the first axis is parallel to or overlaps with the axis of the motor shaft, and when the motor shaft is in the initial position, the cogging torque is zero or the value of the cogging torque is minimum.

11. The electric toothbrush according to claim 10, characterized in that: Before determining that the periodic motion is performed, the motor shaft is in an initial position; and / or after determining that the periodic motion is completed, the motor shaft is in the initial position.

12. The electric toothbrush according to claim 11, characterized in that: When the motor shaft is in the initial position, the bristle portion of the brush head and the user interaction component in the grip portion face the same direction.

13. The electric toothbrush according to claim 10, characterized in that: The periodic rotation has a preset angle, and the initial position of the motor shaft is located at the center of the preset angle.

14. A method for controlling an electric toothbrush, characterized in that: include: Obtaining a trigger instruction, wherein the trigger instruction is used to instruct the motor of the electric toothbrush to perform movement; In response to the trigger instruction, controlling the motor to rotate periodically in a first direction; Obtaining the cogging torque of the motor; When the cogging torque is greater than a first threshold, the motor is controlled to change from a current speed to a first preset speed; wherein the first preset speed is less than the current speed.

15. A motor, applied to an electric toothbrush, the motor being configured to generate a periodic motion, characterized in that: include: A driving body and a motion detection component, wherein: The driving body extending along the first axis includes a stationary component and a rotating component, the rotating component is rotatably mounted on the stationary component, the stationary component at least partially surrounds the rotating component, the stationary component is formed with a receiving chamber, and at least one end of the rotating component extends along the first axis and protrudes to the outside of the stationary component; The motion detection component at least partially located in the accommodating chamber includes a Hall sensor and a motion feedback component, wherein the motion feedback component is connected to the rotating component and rotates with the rotating component, the Hall sensor is directly connected to the stationary component, and the Hall sensor detects the motion position of the rotating component through the motion feedback component; The rotating component includes a motor shaft, which rotates periodically in a first direction. The motor is configured to control the motor to change from a current speed to a first preset speed when the cogging torque of the motor is greater than a first threshold; wherein the first preset speed is less than the current speed.

16. The motor according to claim 15, characterized in that The motor shaft has an axial passage, and a fluid inlet and a fluid outlet communicating with the axial passage.

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