High-frequency power multi-mode electric toothbrush

Abstract

A high-frequency power multi-mode electric toothbrush comprises a body shell, a shimmy motor, a battery, a rotary brush rod and a shimmy brush rod, the body shell is hollow to form a built-in space, and the rear end of the body shell is closed through a detachable tail cover; a control circuit board is contained in the body shell, a plurality of function buttons connected to the control circuit board are arranged on the side wall of the body shell, a battery is arranged at the rear end of the built-in space and electrically connected to the control circuit board and the shimmy motor, and the shimmy motor is arranged at the front end of the built-in space of the body shell and electrically connected to the control circuit board and the shimmy motor. An output shaft of the shimmy motor extends out of the front end of the body shell and is connected to the body shell to provide power output, and the shimmy motor comprises a motor support, an electromagnetic coil, a vibration arm assembly, a front cover and a magnet; therefore, two modes of the high-frequency rotary brush rod and the high-frequency swing brush rod are effectively considered, the rotation or swing frequency is effectively improved, and the problems of noise and service life of the brush rod under high-frequency work are solved by adopting flexible compensation.

Description

Technical Field

[0001] The utility model relates to the technical field of electric toothbrushes, in particular to a high-frequency power multi-mode electric toothbrush which can be respectively adapted to a high-frequency rotating brush rod and a high-frequency vibrating brush rod. Background Art

[0002] At present, toothbrushes with high-frequency power output can be divided into two types according to the movement of the brush head: one is that the brush rod and the brush head are integrated, and the entire brush rod oscillates, and the other is that the brush head is circular or elliptical reciprocating. Generally, the reciprocating rotation of the brush head faces far more technical problems than the vibration of the entire brush rod. The main common problems are:

[0003] 1. The brush head moves in a rotating manner, and is often designed to consist of a brush rod composed of multiple moving parts. Common designs include: a rotating shaft, a mechanism that drives or links the brush plate. Due to manufacturing tolerances, it is difficult to avoid noise in the movement coordination of these mechanisms.

[0004] 2. The long-term use of the brush head in the presence of cleaning abrasive materials such as toothpaste will increase the wear of the moving components, further increasing the noise. The wear of the workpiece will cause the loss of the actual movement stroke between the components, which will eventually manifest as the gradual deterioration and weakening of the output swing angle of the brush disc, which cannot meet the cleaning requirements.

[0005] 3. The maximum operating speed of a conventional economical DC motor-driven electric toothbrush is less than 133Hz, and a gear set or lever connecting rod is required to complete the torque conversion. Otherwise, the direct drive output torque is too small to meet the power demand for cleaning. For example, in order to ensure that the brush head can effectively work at 140-350Hz, the torque conversion of the gear set, the DC motor speed must be much higher than the brush plate output by 2-4 times. Under this condition, the conventional power conversion mechanism will produce high working noise that makes the user uncomfortable, and the wear of the components will also increase sharply due to the increase in speed, affecting the product life. The utility model proposes a high-frequency oscillating vibration motor that is directly driven without a torque conversion mechanism.

[0006] 4. Common electric toothbrushes can only be adapted to one type of cleaning mode: a reciprocating rotating brush head or a high-frequency oscillating brush head. You can only choose one of the two.

[0007] To this end, in view of the above defects, the designers of the present utility model have devoted themselves to research and design, and combined the experience and achievements of many years in related industries to research and design a high-frequency power multi-mode electric toothbrush to overcome the above defects. Utility Model Content

[0008] The purpose of the utility model is to provide a high-frequency powered multi-mode electric toothbrush which can overcome the defects of the prior art and is driven by oscillating force, thereby overcoming the defects of the up and down push-pull torque in the prior art, effectively taking into account the two modes of the high-frequency rotating brush rod and the high-frequency oscillating brush rod, and the rotation or swinging frequency is effectively improved. Flexible compensation is used to solve the noise and life problems of the brush rod under high-frequency operation.

[0009] To achieve the above-mentioned purpose, the utility model discloses a high-frequency power multi-mode electric toothbrush, comprising a body shell, an oscillating motor, a rotating brush rod and an oscillating brush rod, wherein the body shell is hollow to form a built-in space, a control circuit board is placed in the body shell, and a plurality of function buttons connected to the control circuit board are arranged on the side wall, characterized in that:

[0010] The built-in space of the body shell is provided with a swing vibration motor, the output shaft of the swing vibration motor extends from the front end of the body shell to provide power output, the swing vibration motor comprises a motor bracket, an electromagnetic coil, a vibration arm assembly, a front cover and a magnet, the front end of the motor bracket is provided with a front cover, the rear end is provided with a magnet, and the rear side of the magnet is also provided with a shock absorbing block, an inner hollow cavity is formed in the motor bracket to accommodate the vibration arm assembly, and the rear outer edge of the inner hollow cavity is covered with an electromagnetic coil;

[0011] The vibration arm assembly includes a swing arm, a rotating shaft, a bearing and a connecting frame. The rear part of the swing arm is located in the electromagnetic coil at the rear part of the inner hollow cavity. The front part of the swing arm forms a disc portion and the disc portion is provided with an axial hole for the rotating shaft to pass through. Both ends of the rotating shaft are rotatably supported on the motor bracket through bearings. The rear end of the connecting frame covers the front part of the swing arm and forms a cylindrical structure for accommodating the disc portion of the swing arm. The front end of the connecting frame is connected to the rear end of the output shaft to transmit the vibration generated by the vibration arm assembly to the output shaft for output.

[0012] Wherein: the swing arm, the rotating shaft and the output shaft are embedded in one piece to form a vibration arm assembly by means of secondary plastic injection molding to form a connecting frame; the swing arm is a straight iron swing arm and the rotation axis of the rotating shaft is perpendicular to the swing direction of the swing arm.

[0013] Wherein: both ends of the rotating shaft are provided with shaft shoulders matching with the bearings, and the rear end of the output shaft is provided with at least one concave ring, so that the output shaft and the connecting frame are stably formed into one piece after the secondary injection molding.

[0014] Wherein: the swing arm is made of stacked silicon steel sheets with high frequency and low eddy current loss.

[0015] Wherein: the rotating brush rod comprises a brush rod shell, an inner bracket, a rotating brush head assembly and a power transmission assembly, the inner bracket is arranged in the brush rod shell to form an inner space of the built-in power transmission assembly, the rotating brush head assembly is arranged at the front end of the brush rod shell, the rear end of the power transmission assembly is connected to the output shaft of the oscillating motor, and the front end is connected to the rotating brush head assembly, so as to transmit the output power of the oscillating motor to the rotating brush head assembly.

[0016] Wherein: the rotating brush head assembly includes a brush head seat and rotating bristles. The brush head seat is rotatably arranged in the front end of the brush rod shell, one end of which is planted with multiple rotating bristles for cleaning, and the other end is provided with a base connected to the rotating power transmission assembly.

[0017] Wherein: the rotational power transmission component includes a rocker arm, an elastic fulcrum, an elastic coupling body, a driving head, a compensation spring and a connecting sleeve, the front end of the rocker arm is provided with a driving head extending into the base of the brush head seat, the base of the brush head seat forms a passive part that matches the shape of the driving head, the rocker arm is provided with a compensation spring between the driving head and the elastic fulcrum, the rear end of the rocker arm extends into the front end of the connecting sleeve, and the rear end of the connecting sleeve is connected to the output shaft through the elastic coupling body.

[0018] Wherein: the oscillating brush rod comprises a brush rod shell, an internal bracket, an oscillating brush head assembly and an oscillating force transmission assembly, the internal bracket is arranged in the brush rod shell to form an inner space with a built-in oscillating force transmission assembly, the oscillating brush head assembly is arranged at the front end of the brush rod shell, the rear end of the oscillating force transmission assembly is connected to the output shaft of the oscillating motor, and the front end is connected to the oscillating brush head assembly, thereby transmitting the output power of the oscillating motor to the oscillating brush head assembly.

[0019] Wherein: the oscillating brush head assembly includes a brush rod head, a rotating shaft, a bristle bundle seat and oscillating bristles, the rear end of the brush rod head extends into the front end of the brush rod shell and is rotatably fixed to the internal bracket through the rotating shaft, the front end of the brush rod head is fixed with a bristle bundle seat, and the bristle bundle seat is planted with multiple oscillating bristles for cleaning.

[0020] Wherein: the swing force transmission component includes a swing shaft, a coupling block and a connecting tube, the front end of the swing shaft is embedded in the concave hole at the rear end of the brush rod head, and the rear end extends into the front end of the connecting tube, and the rear end of the connecting tube is connected to the output shaft through the coupling block.

[0021] From the above content, it can be seen that the high-frequency power multi-mode electric toothbrush of the utility model has the following effects:

[0022] 1. The technology of high-frequency rotary toothbrushes that can effectively work at 140-350Hz uses a high-torque output oscillating motor to replace the traditional DC motor, reducing the noise caused by the gear set or connecting rod torque conversion link. The replaceable toothbrush rod realizes power coupling through the coupling set on the brush rod, and the body oscillating torque is transmitted to the brush rod through the brush rod swing shaft using the lever principle to realize torque transmission, driving the brush rod to swing. At the same time, it can be equipped with a non-rotating brush rod that works in a swinging manner. The brush rod realizes high-frequency reciprocating swing under the drive of the oscillating motor to meet the diverse requirements of users.

[0023] 2. The oscillating motor drives the brush rod in the form of a connecting rod and a lever, and a gap compensation mechanism is set at the connecting rod joint and the lever fulcrum, which effectively solves the life problems of high noise and easy wear in actual use.

[0024] 3. It takes into account both high-frequency rotary brush bar and high-frequency oscillating brush bar modes.

[0025] The details of the present invention can be obtained from the following description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The schematic diagram of the structure of an embodiment of the high-frequency power multi-mode electric toothbrush of the utility model in which the rotating brush rod cooperates with the oscillating motor is shown.

[0027] Figure 2 The schematic diagram of the structure of an embodiment of the cooperation between the oscillating brush rod and the oscillating motor in the high-frequency power multi-mode electric toothbrush of the utility model is shown.

[0028] Figure 3 The schematic diagram of the structure of the swing vibration motor in the utility model is shown.

[0029] Figure 4 A schematic diagram showing the internal components of the swing vibration motor in the present invention is shown in a half-cut manner.

[0030] Figure 5 The exploded schematic diagram of the pendulum vibration motor in the utility model is shown.

[0031] Figure 6 A cross-sectional view of the swing motor of the utility model is shown.

[0032] Figure 7 A cross-sectional view of the oscillating motor in the utility model is shown in another direction.

[0033] Figure 8 The schematic diagram of the structure of the vibration arm assembly of the swing vibration motor in the utility model is shown.

[0034] Fig.9A , Fig. 9B and Fig. 9CThe schematic diagram shows the three states of the pendulum vibration motor in the utility model under the action of electromagnetic force, wherein Fig.9A and Fig. 9C They are in opposite swinging state. Fig. 9B It is the static state where the current stops.

[0035] Fig. 10A and Fig. 10B Two principle schematic diagrams of the magnetic poles of the oscillating motor in the utility model are shown.

[0036] Fig.11 The overall structural schematic diagram of the rotating brush rod of the utility model is shown.

[0037] Fig.12 The utility model shows a schematic diagram of the exploded structure of the rotating brush rod.

[0038] Fig.13 The utility model shows a schematic diagram of the internal structure of the rotating brush rod.

[0039] Fig.14 The internal schematic diagram of the rotating brush rod of the utility model is shown.

[0040] Fig.15A , Fig. 15B and Fig. 15C Schematic diagrams showing three action states of the rotating brush rod of the utility model are shown respectively.

[0041] Fig.16 The schematic diagram of the structure of the brush head seat in the rotating brush rod of the utility model is shown.

[0042] Fig.17 A partial cutaway view of an elastic coupling body in a rotating brush rod of the utility model is shown.

[0043] Fig.18A A partial cutaway view of an elastic fulcrum in a rotating brush rod of the utility model is shown.

[0044] Fig.18B A cross-sectional view of another embodiment of the rotating brush rod of the present invention is shown.

[0045] Fig.19A and Fig.19B The schematic diagram shows the principle of the compensation spring of the rotating brush rod in the utility model.

[0046] Fig. 20A and Fig. 20B The figure shows a structural schematic diagram of another embodiment of the rotating brush rod of the utility model.

[0047] Fig.21A and Fig.21B The figure shows a structural schematic diagram of another embodiment of the rotating brush rod of the utility model.

[0048] Fig.22A , Fig. 22B , Fig. 22C and Fig.22D The figure shows a structural schematic diagram of another embodiment of the rotating brush rod of the utility model.

[0049] Fig.23A and Fig. 23B The schematic diagram shows the motion trajectory of the output shaft of the rotating brush rod of the utility model being an arc circle.

[0050] Fig.24A and Fig. 24B The schematic diagram shows that the motion trajectory of the output shaft in the rotating brush rod of the utility model is a reciprocating parallel line.

[0051] Fig.25 The overall schematic diagram of the oscillating brush rod of the utility model is shown.

[0052] Fig.26 The figure shows the internal structure of the oscillating brush rod of the utility model.

[0053] Fig. 27 The exploded schematic diagram of the swing brush rod in the utility model is shown.

[0054] Fig.28 A schematic diagram of the gap of the swing brush rod in the utility model is shown.

[0055] Fig.29A , Fig.29B and Fig.29C The schematic diagram of the action of the swing brush rod in the utility model is shown.

[0056] Fig.30 The voltage signal waveform diagram of a typical H-bridge output terminal of the swing motor in the utility model connected to a pure resistance load is shown.

[0057] Fig.31 The schematic diagram shows the principle of collecting power and current of the oscillating motor in the utility model without additional sensor devices.

[0058] Fig.32 The true value diagram of the four typical working states of the H bridge of the pendulum vibration motor in the utility model is shown.

[0059] Fig.33 The schematic diagram shows the signal of the H-drive bridge of the swing vibration motor in the utility model connected to the pure resistance load and the inductive motor load.

[0060] Fig.34 The schematic diagram shows that the battery terminal voltage of the pendulum vibration motor in the utility model is directly measured when working, and the pendulum vibration motor exhibits different swing amplitudes and wave clusters under different loads.

[0061] Fig.35 Shows Fig.34 A scatter plot showing the correlation data in .

[0062] Fig.36 A schematic diagram showing the asynchronous continuous and dense voltage sampling of the oscillating motor in the utility model is shown.

[0063] Fig.37 A schematic diagram showing the voltage data of the synchronous sampling method of the swing vibration motor in the utility model.

[0064] Fig.38 The schematic diagram shows the principle of the short-circuited H-bridge of the oscillating motor in the utility model to absorb the back electromotive force.

[0065] Fig.39 A comparison diagram of current signals of the swing motor of the utility model before and after the back electromotive force is eliminated is shown.

[0066] Fig.40 The process principle block diagram showing the constant amplitude correction technology of the swing motor in the utility model

[0067] Fig.41 The graph shows the comparison of the swing angle change curves with and without compensation when the load of the swing motor in the utility model changes.

[0068] Fig.42 The utility model shows a signal processing flow chart of a dynamic servo process for the swing motor to obtain a constant output swing amplitude of the motor.

[0069] Reference numerals:

[0070] 10. Body shell; 11. Tail cover; 12. Function button; 13. Control circuit board; 20. Swing motor; 21. Motor bracket; 22. Electromagnetic coil; 23. Shock absorber; 24. Vibration arm assembly; 241. Swing arm; 242. Rotating shaft; 243. Bearing; 244. Connecting frame; 245. Output shaft; 25. Front cover; 26. Sealing cover; 27. Magnet; 30. Battery; 41. Brush rod housing; 421. Brush head seat; 422. Rotating bristles; 4 23. Fixed frame; 424. Rotating shaft; 425. Safety nail; 426. Compensating spring pad; 43. Rocker arm; 44. Elastic fulcrum; 45. Elastic coupling body; 46. Driving head; 47. Inner bracket; 48. Compensating spring; 49. Connecting sleeve; 51. Brush rod housing; 521. Brush rod head; 522. Rotating shaft; 523. Bristle seat; 524. Oscillating bristles; 53. Rocker shaft; 54. Coupling block; 55. Connecting pipe; 56. Inner bracket; 57 Compensating pad. DETAILED DESCRIPTION

[0071] See also Figure 1and 2 , showing the high-frequency power multi-mode electric toothbrush of the utility model, wherein Figure 1 The schematic diagram of the structure of the embodiment of the high-frequency power multi-mode electric toothbrush of the utility model in which the rotating brush rod cooperates with the oscillating motor is shown. Figure 2 The schematic diagram of the structure of an embodiment of the cooperation between the oscillating brush rod and the oscillating motor in the high-frequency power multi-mode electric toothbrush of the utility model is shown.

[0072] Therefore, the high-frequency powered multi-mode electric toothbrush includes a main body shell 10, an oscillating motor 20, a battery 30, a rotating brush rod and an oscillating brush rod. The main body shell 10 is hollow to form a built-in space, and its rear end is closed by a detachable tail cover 11. The main body shell 10 contains a control circuit board 13 and has a plurality of function buttons 12 connected to the control circuit board 13 on the side wall, so that the operator can provide a control signal to the control circuit board 13 through the function button 12 to achieve the purpose of controlling the electric toothbrush.

[0073] A swing motor 20 is provided at the front end of the built-in space of the main body shell 10, and the output shaft 245 of the swing motor 20 extends from the front end of the main body shell 10 and is connected to the brush rod located in front of the main body shell 10 to provide power output for the brush rod. A battery 30 is provided at the rear end of the built-in space, and the battery 30 is electrically connected to the control circuit board 13 and the swing motor 20 to provide stable and reliable power output for both.

[0074] exist Figure 1 In the embodiment, the rotating brush rod is detachably connected to the front end of the main body shell 10, and the output shaft 245 extends into the rotating brush rod to provide driving force. Figure 2 In the embodiment of the present invention, the oscillating brush rod is detachably connected to the front end of the main body shell 10, and the output shaft 245 is inserted into the oscillating brush rod to provide driving force. Thus, the main body shell 10 is detachably connected to the rotating brush rod or the oscillating brush rod, thereby taking into account the advantages of both high-frequency rotating brush rod and high-frequency oscillating brush rod, thereby better improving the scope of application.

[0075] See also Figures 3 to 9C , in order to better understand a specific embodiment of the swing vibration motor in the utility model.

[0076] In this embodiment, the oscillating motor 20 includes a motor bracket 21, an electromagnetic coil 22, a shock absorbing block 23, a vibration arm assembly 24, a front cover 25 and a magnet 27. Figure 5 The exploded diagram shown and Figure 6 , Figure 7It can be seen more clearly from the cross-sectional view that the front end of the motor bracket 21 is provided with a front cover 25, the rear end is provided with a magnet 27, and the rear side of the magnet 27 is also provided with a shock-absorbing block 23, so that the vibration of the swing motor 20 can be isolated from the battery on the rear side, thereby achieving a shock-absorbing function and avoiding excessive vibration during use that causes the user's comfort to deteriorate.

[0077] The motor bracket 21 forms an inner hollow cavity to accommodate the vibration arm assembly 24, and the outer edge of the rear of the inner hollow cavity is covered with an electromagnetic coil 22. Figure 8 The vibration arm assembly 24 includes a swing arm 241, a rotating shaft 242, a bearing 243 and a connecting frame 244. The swing arm 241 is a straight iron swing arm and its rear portion is located in the electromagnetic coil 22 at the rear of the inner hollow cavity. The front portion of the swing arm 241 forms a disc portion and the disc portion is provided with an axial hole for the rotating shaft 242 to pass through. Both ends of the rotating shaft 242 are rotatably supported on the motor bracket 21 through bearings 243. The rear end of the connecting frame 244 covers the front portion of the swing arm 241 and forms a cylindrical structure for accommodating the disc portion of the swing arm 241. The front end of the connecting frame 244 is connected to the rear end of the output shaft 245 to transmit the vibration generated by the vibration arm assembly 24 to the output shaft 245 for output.

[0078] Among them, the swing arm 241, the rotating shaft 242, and the output shaft 245 are embedded in one piece to form a vibration arm assembly by adopting a plastic secondary injection molding method to form a connecting frame 244. The rotation axis of the rotating shaft 242 and the swing direction of the swing arm 241 are perpendicular to each other. The rotating shaft 243 is preferably arranged in a rotating shaft hole at about 2 / 3 of the swing arm 241, so that the rotating shaft and the swing arm are cross-shaped after being combined. Both ends of the rotating shaft 242 are provided with shoulders that cooperate with the bearing 243, and the rear end of the output shaft 245 is provided with at least one concave ring, so that after the secondary injection molding, the output shaft 245 and the connecting frame 244 are stably integrated, and the at least one concave ring of the output shaft 245 can effectively prevent the output from being displaced under the action of external force.

[0079] Therefore, the oscillating motor is a power conversion device that converts electromagnetic energy into mechanical energy. Under the same power consumption conditions, the final output driving torque of the oscillating motor is 2-5 times the output torque of the traditional DC motor of the same volume under the same working conditions, so as to meet the high-frequency oscillation power requirements of the electric toothbrush.

[0080] Also see Fig.9A , Fig. 9B as well as Fig. 9CThe vibration arm assembly is placed in the hollow body of the device, and a space is formed between the rear part of the swing arm 241 and the inner wall of the motor bracket 21, which can allow the swing arm 241 to swing back and forth 20 degrees without colliding with the motor bracket. The rear end of the motor bracket 21 forms a step portion for accommodating the magnet 27 so that a gap of at least 0.2-0.6mm is maintained between the end of the swing arm 241 and the magnet, so that the magnet 27 at the tail can induce a magnetic force on the tail of the iron swing arm, but there is no physical contact.

[0081] Two magnets are arranged in parallel at the tail of the bracket, with the magnetized surface facing the swing arm. After the two magnets are combined, the polarities in the same direction are opposite to each other.

[0082] The front cover 25 at the front end of the motor bracket 21 is covered with a sealing cover 26 to achieve sealing. The provision of the front cover strengthens the stability of the bearings at both ends of the rotating shaft and provides a limit for the sealing cover.

[0083] The process of converting the electromagnetic force of the oscillating motor proposed in the present invention into oscillating mechanical energy is as follows:

[0084] 1. Connect the electromagnetic coil to a square wave power current with alternating positive and negative polarity.

[0085] 2. If Fig.9A As shown, assuming that in the positive half cycle of the square wave, because an iron swing arm is built into the electromagnetic coil, the axis of the swing arm is in the same direction as the axis of the electromagnetic coil, and the swing arm will be polarized and magnetic under the action of the electromagnetic field. Assuming that the swing arm close to the magnetic pole is polarized to the S pole at this moment, under the principle of repulsion between the same poles and attraction between the opposite poles, the swing arm of the vibration arm assembly will swing in the direction of D1.

[0086] 3. Such as Fig. 9C As shown, when the square wave current switches to the negative half cycle, the polarity of the electromagnetic coil power supply is reversed, and the current acting on the electromagnetic coil is opposite to the direction of the positive half cycle. The induced magnetic pole of the swing arm is transformed into the N pole. Similarly, the swing arm of the vibration arm assembly will switch in the opposite direction from D1 to D2 under the action of the new electromagnetic force.

[0087] 4. After completing the current switching of the positive and negative half cycles, the swing of the vibration arm assembly of the motor constitutes a complete vibration cycle. The swing frequency of the vibration arm assembly depends on the frequency of the square wave current of the driving coil. In the embodiment of the utility model, the electromagnetic coil preferably operates at 140Hz-350Hz. The strength of the swing angle of the vibration arm assembly can be adjusted by the duty cycle of the square wave, and the swing angle is proportional to the duty cycle.

[0088] The swing arm 241 is supported by ferromagnetic materials. Since the operating frequency can be as high as 350 Hz, the swing arm 241 is made of stacked silicon steel sheets with high frequency and low eddy current loss.

[0089] like Fig. 10AAs shown, the magnet 27 described in the utility model can be two independent magnets M1 arranged to form a magnetic pole, or it can be as shown in FIG. Fig. 10B As shown, the same-plane multi-pole magnetization process is adopted, and only one magnet M2 is used to magnetize the N and S poles simultaneously and polarize them in the same plane. The arrangement direction of N and S is consistent with the polarity of the two magnets to meet the requirements of the utility model.

[0090] Among them, the sensorless synchronous drive pulse detection battery voltage technology is adopted, relying on the specific drive pulse cycle to monitor the change of drive current caused by the dynamic impedance change of the motor. Combined with the corresponding algorithm and the monitored motor working conditions, the drive power is compensated in real time to achieve constant swing output.

[0091] Among them, in one embodiment of the oscillating motor, it involves a constant amplitude control method, in which the typical driving wave voltage shape is a square wave, and the frequency of the square wave is consistent with the output swing frequency. Theoretically, under the condition of constant voltage, when the motor outputs full power, the duty cycle of the square wave should be 100%. In practical applications, the most basic driving power device is an H-driven bridge composed of 4 FETs. The H-bridge changes with the input signal, and the positive and negative voltages at the output end are switched at high speed. Because the FET switching has a response time difference, if it is switched at a duty cycle of 100%, there will be a situation where the 4 FETs of the H-bridge are turned on at the same time, causing an internal short circuit of the H-bridge, resulting in damage to the H-bridge drive. The fastest response interval is usually called the dead zone of the H-bridge drive. Therefore, the H-bridge should avoid working in the dead zone, and the power supply to the motor should be stopped in this interval. After considering the dead zone, the maximum duty cycle of the final square wave is usually 98% to 99% instead of 100%.

[0092] If the duty cycle of the pulse is reduced in the reverse direction, the effective power of the drive will decrease in the reverse direction, so that the swing amplitude of the swing motor will decrease accordingly. The mechanism by which the output power can be changed by adjusting the duty cycle of the pulse serves as the theoretical basis for the output rate compensation of the swing motor mentioned in the utility model.

[0093] like Fig.30As shown, a typical voltage signal waveform diagram of a H-bridge output terminal connected to a pure resistance load is shown, in which: S1 is a positive half-cycle effective working pulse, S2 is a negative half-cycle effective working pulse, t12, t22 are respectively positive and negative half-cycle working stop cycles, which include the necessary dead zone control time and the stop time for adjusting the entire pulse duty cycle, t is a complete driving cycle, t=S1+S2+t12+t22; assuming that S1=S2, t12=t22 are completely symmetrical in the positive and negative half cycles; Duty=S1 / (t12+S1)X100% or Duty=S2 / (t22+S2)X100%, in actual control, by synchronously adjusting the ratio of t12, t22 in the entire pulse t, that is, the duty ratio parameter, the power control of the drive can be realized. It is obvious that the larger the proportion of t12 and t22 cycles, the smaller the output power. Controlling the output power by adjusting the duty ratio is the theoretical basis of the control technology of the motor of the utility model.

[0094] Before discussing how to implement the motor constant amplitude control theory mentioned in the utility model, the principle and method of collecting power current without additional sensor devices are first explained, such as Fig.31 As shown, a schematic diagram of the power current acquisition principle without additional sensor devices is shown, wherein BT: represents a battery pack, V inside the battery pack is a standard battery, and R0 is the internal resistance of the battery pack; MCU: is a microprocessor of a line control unit, and the microprocessor contains an analog-to-digital converter marked as ADC and a reference voltage reference source for ADC with an internal mark Vref; S1~S4: are output drive signal ports specially set by the MCU for the H bridge; H: is an H power drive bridge composed of two pairs of complementary FETs; M: is the oscillating motor involved in the utility model; I: is the power current.

[0095] Fig.32 The true values ​​of the four typical working states of the H-bridge are shown.

[0096] Among them, the current sampling required by the constant amplitude technology involved in the utility model has two key points:

[0097] 1. Taking advantage of the internal resistance R0 of the battery pack, during power driving, the changing power current I will inevitably produce a changing voltage drop Vdp at R0. The change in load current can be reflected by detecting Vdp through the MCU control unit, that is, Vdp = R0 XI.

[0098] 2. In order to simplify the hardware design, a microprocessor with a built-in analog-to-digital converter ADC and a voltage reference source Vref is selected, so that the change of power current can be calculated directly without more external designs.

[0099] Unless otherwise specified, the power current change detection discussed in this article is implemented based on the method of detecting the change of R0 voltage drop Vdp.

[0100] The following is divided into two parts to further explain the implementation method and process of constant amplitude compensation.

[0101] The signals of the H-bridge connected to pure resistance load and inductive motor load will show obvious differences, such as Fig.33 As shown in the figure, the solid line CV1 is the waveform of the pure resistance load, and the dotted line is the waveform of the pendulum motor with actual inductive reactance. The obvious difference between these two sets of waveforms is that the peak ringing marked as D appears in each working pulse, and each effective working waveform from the starting point a to the end point b, under the influence of the inductive load, changes from the horizontal line of the standard rectangular square wave to a slope line.

[0102] When the drive end is connected to the motor, the square wave has obvious overshoot and ringing, mainly in the stop cycle (dead zone cycle + power regulation cycle), the motor coil is stopped from being powered, the coil is an inductive load and will generate back electromotive force, and the swing arm will continue to cut the magnetic lines of force generated by the magnet under the action of inertia, forming a variable impedance to the coil. The superposition of the back electromotive force of the coil and the variable impedance on the power supply directly affects the stability of the square wave rising edge and pulse width.

[0103] After the coil is powered off, the swing arm continues to swing under the action of inertia. Assuming that the swing frequency remains unchanged, the larger the swing amplitude, the greater the speed at which the magnetized swing arm cuts the magnetic force lines, and the greater the impact on the variable impedance generated by the coil. Obviously, if the instantaneous current related to the influence of the variable impedance can be measured, the current swing linear velocity of the swing arm can be relatively mapped, that is, the current relative change in the output swing. This idea is the most important theoretical basis for the real-time swing amplitude measurement involved in the constant amplitude drive technology mentioned in the utility model.

[0104] In order to reduce the impact of electromagnetic interference in stray space on signal detection, the swing-related data detection mentioned in the utility model is not set at the motor drive output end, but directly measures the instantaneous voltage change at the battery end. The voltage change and the current change at the motor drive end have a mutual mapping relationship.

[0105] Fig.34 The voltage at the battery terminal during direct measurement at work is shown. Under different loads, the oscillating motor exhibits different swing amplitudes and wave clusters. The solid line curve CV1 in the figure is the waveform under no-load conditions, and the dashed line curves CV2, CV3, CV4, and CV5 are the waveforms exhibited when the load increases from small to large. It can be observed that the voltage at the battery terminal changes with the load at a certain timing of each drive pulse. For example, the correlation between the motor load and the voltage can be clearly observed in the interval t1 to t2 in the attached figure. The heavier the load, the higher the voltage. The rules summarized are:

[0106] Load: CV5>CV4>CV3>CV2>CV1;

[0107] Pulse end voltage: V5>V4>V3>V2>V1.

[0108] Fig.35 The data is displayed in a scatter plot. In the figure, the V axis is the battery terminal voltage, and the D axis is the swing angle of the pendulum shaft. The heavier the load, the smaller the swing angle of the pendulum shaft.

[0109] V5~V1 are 5 sampling points, and curve a is the curve obtained by connecting the actual sampling points in series. It can be clearly seen from the attached figure that the voltage of the sampling point is strongly correlated with the swing angle under different loads. In order to simplify the calculation amount of the microprocessor, the above sampling data can be fitted with a straight line b using the least squares method.

[0110] The instantaneous voltage change U at the battery end is affected by two important factors, namely U=Ub+Ur, where Ub is the back electromotive force generated by the motor power-off stop cycle, and Ur is the change in the dynamic inductance of the coil caused by the change in the swing amplitude of the vibration arm position. The change in dynamic inductance directly affects the change in the conduction rate of the current in the coil, essentially forming a changing impedance. The change in coil impedance will eventually affect the performance of the rising edge of each pulse at the motor coil end.

[0111] Therefore, as long as the voltage change component caused by the impedance change of the motor at the rising edge of each pulse can be effectively separated, the current motor swing data can be quantified.

[0112] In order to better separate the changing impedance of the motor coil, it is particularly important to select the right sampling point for the current. It can be seen from the wave cluster that, unlike the conventional sampling method, if it is a conventional DC motor working condition, the conventional method is to ignore the pulse synchronization information and continuously perform equidistant and dense sampling. The longer the sampling period, the more stable the value after weighted averaging, which can well reflect the relationship between voltage and load. However, it has been proved that this non-synchronous averaging method is ineffective for brushless motors driven by pulse commutation. The voltage results obtained by continuous sampling without pulse synchronization have no obvious correlation with load changes.

[0113] Fig.36 The performance of asynchronous continuous and dense voltage sampling in brushless motors is shown: In the figure: V axis: voltage scalar, T axis: time scalar, S1~Sn is the timing of asynchronous continuous sampling, t2 is the sampling period, P1~pn is the voltage change periodic signal observed at the battery end. Obviously, this period is related to and synchronized with the motor drive pulse phase, t1 is the motor drive pulse period, and D1~Dn are the sampled voltage values

[0114] As can be seen from the figure, if t1 and t2 are not synchronized, the sampling positions of D1 and D5 are significantly different from the pulse rise and fall positions, where D1 is close to the head of pulse P1 and D5 is close to the tail of pulse P3, and the difference between the two sampling values ​​is large. Therefore, the weighted average method can be used to average the data: that is, Avg = (D1 + D2 + Dn...) / n... The average value Avg does not correctly capture the correct correlation data between the load and the voltage, so the traditional asynchronous voltage sampling is not suitable for the oscillating motor working condition mentioned in the utility model.

[0115] Fig.37 The performance of voltage data in synchronous sampling mode is shown in the figure: V axis: voltage scalar, T axis: time scalar, S1~Sn is the timing of asynchronous continuous sampling, t2 is the sampling period, P1~pn is the voltage change period signal observed at the battery end, and it is obvious that the period is related and synchronized with the pulse phase. t1 is the motor drive pulse period, and D1~Dn are the sampled voltage values.

[0116] from Fig.37 It can be observed that, if t1 is synchronized with t2, the sampling positions of D1, D2, D3...Dn are consistent with the pulse rise and fall positions. It is assumed that the weighted average method is used to average the data: that is, Avg = (D1+D2+Dn...) / n..., the average value Avg can correctly capture the correct correlation data between the load and the voltage. Therefore, synchronous voltage sampling is the preferred current sampling scheme for the oscillating motor mentioned in the utility model.

[0117] Based on the data performance in the above two figures, it is obvious to explain the difference between the traditional simple weighted average current sampling mode and the synchronous sampling. The oscillating motor generally belongs to the category of brushless motors, which are all power pulse drives with high-frequency switching of positive and negative polarity pulses. The sampling mode synchronized with the pulse phase must be used to parse out the current information related to the load.

[0118] After synchronous sampling is adopted, in order to further improve the signal quality, some additional technical means are still needed to filter the back electromotive force signal generated by the unnecessary coil that affects the load current performance.

[0119] In addition to including the dynamic impedance information of the coil, the overcharge amount on the rising edge of the pulse also includes the back electromotive force generated after the coil is powered off. If the information of the overshoot amount on the rising edge of each pulse is directly used to quantify the swing amplitude relationship without considering the superposition effect of the back electromotive force on the signal, the existence of the back electromotive force will more or less reduce the accuracy of the quantitative analysis. In order to eliminate the influence of the back electromotive force on the overshoot amount on the rising edge of each pulse, the H-bridge can be used to momentarily short-circuit the motor coil during each stop cycle of the drive to quickly release the back electromotive force. The embodiment proves that after eliminating the back electromotive force, the motor swing amplitude change can be monitored more sensitively, which improves the signal-to-noise ratio of the signal.

[0120] thus, Fig.38 This is a schematic diagram of the principle of short-circuiting the H-bridge to absorb the back electromotive force. In the figure: F1~F4 are two pairs of complementary NP-channel FETs that form an H-bridge as the drive of the oscillating motor, and M is the oscillating motor. Before starting the motor current detection and after the driving power is disconnected, the S1 and S2 inputs are set to a high level, and F1 and F2 enter the cut-off state. The S3 and S4 inputs are also input to a high level, and F3 and F4 are turned on. After F3 and F4 are turned on, F3, F4, and M form a loop, short-circuiting the back electromotive force generated at both ends of the motor M, generating a short-circuit current loop C, and the back electromotive force is converted into heat energy and dissipated on the motor coil.

[0121] When the back electromotive force is completely absorbed, S3 and S4 jump to high level and enter the cut-off state, starting the ADC conversion of the MCU for current detection.

[0122] Fig.39 A comparison diagram of the current signal before and after the back EMF of the oscillating motor is eliminated is shown. In the figure: V axis: voltage scalar, T axis: time scalar, P1~P3 show 3 groups of pulse periodic signals, CV1 solid line curve is the voltage curve after the back EMF is eliminated by short-circuit technology, CV2 dotted line curve is the voltage curve affected by the back EMF, Ts is an important area that includes load change information, C is a ringing peak signal that appears when short-circuiting is not used to eliminate the back EMF, and a is an area where the back EMF has a greater impact.

[0123] Since the shaded area marked a is caused by the signal ringing peak generated by the back electromotive force, it has a serious impact on the effective load signal in the Ts interval. After the ringing peak is absorbed by technical means, it has a positive significance for analyzing the load signal.

[0124] Short-circuiting the back-EMF to eliminate it is helpful to analyze the change of the dynamic impedance of the coil, but it will also have a negative impact on the motor. At the moment of short-circuiting the coil current, heat energy will be generated in the coil, causing the coil operating temperature to rise. Whether to use the back-EMF elimination technology or choose a reasonable short-circuit timing can be determined according to the actual application.

[0125] After obtaining effective swing quantification data, the data can be used to adjust the duty cycle of the drive pulse in real time. When the swing is lower than the set value, the pulse duty cycle is continuously increased, and the drive power is increased to increase the swing. On the contrary, the duty cycle is continuously reduced, and the drive pulse power is reduced to reduce the swing. By using the above-discussed method to dynamically monitor the swing value in real time and dynamically adjust the pulse drive power, a stable output swing can be obtained under load changes.

[0126] Fig.40This is a process principle block diagram of the constant amplitude correction technology involved in the utility model. In the specific implementation column, in addition to solving the problem of analyzing the battery voltage change associated with the swing amplitude, it is also necessary to correctly select the appropriate sampling frequency and adjustment frequency, because ADC data acquisition and processing will consume resources, and too dense data sampling will interfere with the stability of the pulse phase of the drive, resulting in phase jitter, and the motor swing shaft will show irregular swing jitter and produce abnormal noise. The density of the pulse duty cycle adjustment also needs to be appropriate, because the motor swing shaft has rotational inertia and has response time domain requirements. Too dense adjustment will weaken the useful amplitude information analyzed, resulting in overshoot, overshoot oscillation, and cannot be controlled normally. Too sparse adjustment will cause the control to be sluggish and delayed, and the compensation effect is not ideal. Generally, the following factors should be considered in actual control:

[0127] 1. Synchronization point with motor signal: The implementation column proves that it is preferable to select sampling before the pulse is about to end, because the data is most stable and has a high signal-to-noise ratio.

[0128] 2. Start-up back-EMF duration and density: Back-EMF absorption cannot be turned on for every pulse. It should only be enabled before detecting the battery voltage and turned off immediately after the detection is completed. Otherwise, a large amount of heat will be dissipated in the motor coil, causing the motor operating temperature to rise sharply. Similarly, the absorption duration is also a key point in controlling heat, which should be based on the actual situation and the test results.

[0129] 3. Battery voltage sampling: It cannot be performed for every pulse. In the example test of the embodiment, it is better to sample once every 20 pulses. Too intensive sampling will cause phase jitter and abnormal noise in the motor.

[0130] 4. Adjust the motor drive pulse duty cycle frequency: It also needs to be reasonable. Too dense correction will cause overshoot oscillation, too sparse compensation will cause slow response, and the swing amplitude will be unstable after load changes.

[0131] Therefore, the control method comprises the following steps:

[0132] Step 1: Synchronously output pulses (which may be the square wave pulses mentioned above);

[0133] Step 2: Start back-EMF absorption;

[0134] Step 3: synchronously collect battery voltage;

[0135] Step 4: Analyze the load-related variables;

[0136] Step 5: Calculate the correction amount;

[0137] Step 6: Correct the drive duty cycle and return to step 1.

[0138] Fig.42The flowchart of signal processing of the dynamic servo process mentioned in the utility model for obtaining a constant output swing of the motor is shown.

[0139] The steps include:

[0140] Step 1: After the interrupt response, determine whether the 20 pulse intervals are met. If yes, go to step 2, otherwise exit;

[0141] Step 2: Determine whether it is a stop cycle, if yes, go to step 3, otherwise exit;

[0142] Step 3: Start the back electromotive force absorption and determine whether the drive pulse is ended. If yes, go to step 4, otherwise exit;

[0143] Step 4: Collect the battery voltage. If the voltage value is less than the last collected value, go to step 5, otherwise go to step 6;

[0144] Step 5: Increase the duty cycle of the drive pulse and then exit;

[0145] Step 6: Is the voltage value greater than the last collected value? If so, decrease the duty cycle of the drive pulse and exit; otherwise, exit directly.

[0146] The above exit is to directly exit the interrupt response.

[0147] In the embodiment of the utility model, after the system is initialized, the initial pulse duty cycle without compensation is preset to 45%, and is 98% when the maximum compensation is performed.

[0148] Fig.41 The following is a comparison of the swing angle change curves with and without compensation when the load changes, where the ordinate is the swing angle of the swing axis and the abscissa is the force applied to the swing axis. Curve CV1 is the output performance without compensation, and CV2 is the performance after real-time dynamic compensation. It can be seen from the figure that after compensation, the swing amplitude's ability to resist load changes is significantly improved.

[0149] like Figures 11 to 24B As shown, an embodiment of the rotating brush rod of the utility model is shown, see Fig.11 , Fig.12 , Fig.13 and Fig.14 , shows an embodiment of the rotating brush rod of the utility model, wherein Fig.11 The overall structure diagram of the rotating brush rod of the utility model is shown. Fig.12 The schematic diagram of the exploded structure of the rotating brush rod of the utility model is shown. Fig.13 and Fig.14 A detailed schematic diagram showing the internal structure of the rotating brush rod of the utility model.

[0150] Specific as Fig.11 , Fig.12 and Fig.13 As shown, the rotating brush rod includes a brush rod shell 41, an inner bracket 47, a rotating brush head assembly and a power transmission assembly. The brush rod shell 41 is hollow and the rear end is detachably connected to the main unit of the electric toothbrush. The rear portion of the brush rod shell 41 is formed in a trumpet shape and accommodates the inner bracket 47. The inner bracket 47 is trumpet-shaped and adapted to the inner cavity of the brush rod shell 41 and is hollow inside to form an inner space for a built-in power transmission assembly. The front end of the brush rod shell 41 forms a circular groove for accommodating the rotating brush head assembly.

[0151] See also Figure 1 The installation diagram shows a specific embodiment of the rotating brush rod of the utility model applied to an electric toothbrush. In this embodiment, the rear end of the brush rod housing 41 is detachably connected to the front end of the main body shell 10, the rear end of the power transmission assembly is connected to the output shaft 245 of the oscillation motor 20, and the front end is connected to the rotating brush head assembly, thereby transmitting the output power of the oscillation motor 20 to the rotating brush head assembly.

[0152] Specifically, the rotating brush head assembly includes a brush head seat 421 and rotating bristles 422. The brush head seat 421 is rotatably arranged in a circular groove at the front end of the brush rod housing 41. A plurality of rotating bristles 422 for cleaning are planted on the upper end thereof, and a base is provided at the lower end. In the illustrated embodiment, the brush head seat 421 is connected to the brush rod housing 41 via a rotating assembly. The rotating assembly includes a fixing frame 423, a rotating shaft 424 and a safety pin 425. The base of the brush head seat 421 is provided for the fixing frame 423 penetrates through, and the side of the fixing frame 423 is fixed to the brush rod housing 41 by a safety nail 425. The middle part of the fixing frame 423 is provided with a through hole for the rotating shaft 424 to penetrate, and both ends of the rotating shaft 424 extend into the brush head seat 421, so that the fixing frame 423 is relatively fixed to the brush rod housing 41 through the safety nail 425, and the brush head seat 421 rotates relative to the fixing frame 423, so that the brush head seat 421 can rotate in the circular groove through the power transmission of the rotating power component.

[0153] Optionally, a compensation spring washer 426 is provided between the base of the brush head holder 421 and the brush rod housing 41 to provide compensation during rotational motion.

[0154] The power transmission assembly includes a swing rod 43, an elastic fulcrum 44, an elastic coupling body 45, a driving head 46, a compensation spring 48 and a connecting sleeve 49. The front end of the swing rod 43 is provided with a driving head 46 for driving the brush head seat 421. Figure 12 to Figure 14 In the embodiment of the present invention, the drive head 46 is a convex head in this embodiment, and see Fig.16The base of the brush head seat 421 is provided with a groove 4211 which meshes with the convex head, so that the convex head serving as the driving head 46 can extend into and engage with the tooth groove 4211 to realize power transmission between the two, wherein the middle part of the rocker arm 43 is elastically supported on the front end inner wall of the inner bracket 47 through an elastic fulcrum 44, and the rocker arm 43 is provided with a compensation spring 48 between the driving head 46 and the elastic fulcrum 44, and the connecting sleeve 49 is embedded in the rear end of the inner bracket 47, and the rear end of the rocker arm 43 extends into the front end of the connecting sleeve 49, and the rear end of the connecting sleeve 49 is connected to the output shaft 245 of the oscillating motor through an elastic coupling body 45 to transmit power.

[0155] Therefore, the brush head seat of the rotating brush rod is circular or elliptical, and the movement of the brush head seat is a rotary pair. The center of rotation is the center of the circle of the brush head seat around the rotating axis 424. The movement of the circular brush head seat is back and forth rotation in opposite directions. The rotation angle range is usually 10-120 degrees, and the conventional reciprocating rotation frequency is 80-130Hz.

[0156] exist Figure 12 to Figure 14 In a specific embodiment, the rotating brush rod can reliably operate in the range of 80-350 Hz and maintain an effective load swing angle of more than 20 degrees.

[0157] Among them, the free length of the compensation spring 48 is greater than the distance between the elastic fulcrum and the driving head. After the compensation spring 48 is compressed, a reaction force is generated to push the driving member toward the brush head seat. The connecting sleeve 49 is a trumpet-shaped sleeve, and the elastic coupling body 45 is a through-hole elastic body. The protruding end of the output shaft 245 is contained by the elastic coupling body 45.

[0158] Therefore, if Fig.15A , Fig. 15B and Fig. 15C As shown, when the output shaft swings, the power is coupled through the connecting sleeve 49 and the elastic coupling body 45, and the swing arm swings with the elastic fulcrum 44 as the fulcrum. The swing of the swing arm drives the driving member 46 to follow, and the driving member 46 further drives the bristle holder to swing at high speed. When the swing arm swings in the opposite direction, the movement direction of the brush head holder also changes in the opposite direction. The swing of the swing arm in two directions constitutes a complete motion cycle. The mechanics of the action of the swing arm on the brush head holder is essentially a simple lever principle. The position of the elastic fulcrum at the top of the inner bracket determines the size of the output swing angle and output torque of the brush head. The closer the elastic fulcrum moves to the brush head, the smaller the swing angle of the brush head holder and the greater the torque of the brush head holder. Conversely, the swing angle of the brush head holder becomes larger and the torque of the brush piece decreases.

[0159] Among them, Fig.17As shown, the front end of the connecting sleeve 49 is tightly matched with the rear end of the rocker arm 43, and the rear end accommodates the elastic coupling body 45. The middle part of the elastic coupling body 45 is provided with a concave ring convex ring 451, and the connecting sleeve 49 is correspondingly provided with an inner protrusion that extends into the concave space of the elastic coupling body 45. The cooperation between the concave ring convex ring 451 and the inner protrusion can better cooperate with the output shaft of the rocker motor for power transmission.

[0160] Fig.18A As shown, in a preferred embodiment of the utility model, a concave ring 441 is provided in the middle of the elastic fulcrum 44, and a corresponding convex portion is provided at the front end of the inner bracket 47 which is concave and extends into the concave space of the elastic fulcrum 44, so that the concave ring 441 of the elastic fulcrum 44 is tightly matched with the middle of the rocker arm 43 and the outer edge of the elastic fulcrum 44 is also in contact with the inner bracket 47, so that the rocker arm 43 can swing stably with the elastic fulcrum 44 as the fulcrum.

[0161] Among them, Fig.18B In another embodiment shown in the figure, another form of the power transmission assembly of the rotating brush rod of the utility model is shown. In this embodiment, the structure of the connecting sleeve 49' and the elastic coupling body 45' is similar to that of the embodiment shown in the figure. Figures 11 to 14 There is a difference. In this embodiment, the outer edge of the elastic coupling body 45' corresponding to the inner concave ring convex ring 451 is provided with an outer protrusion to extend into a hollow groove of the connecting sleeve 49' to achieve stable coupling between the connecting sleeve 49' and the elastic coupling body 45'. This structure can better achieve dynamic coupling between the connecting sleeve 49' and the elastic coupling body 45'.

[0162] like Fig.19A and Fig.19B As shown, by arranging a compensation spring 48 between the elastic fulcrum and the driving head, the free length L2 of the compensation spring 48 is greater than the distance L1 between the elastic fulcrum and the driving head. Therefore, when the compensation spring 48 is compressed, a constant reaction force will be generated to push the driving head toward the brush head seat, so that the two are in close contact at any time, so that the gap between the two can be eliminated at any time. Therefore, the compensation spring 48 can be referred to as an elastic compensation gap elimination mechanism. The elastic compensation gap elimination mechanism will produce the following improvement effect on the performance under the following working conditions:

[0163] 1. During the brushing process, the brush head seat will lose engagement with the surface of the drive head due to load changes, resulting in a matching gap. At this time, the elastic compensation and clearance-eliminating mechanism will take effect, and the toothed surface will be tightened under the reaction force of the compensation spring.

[0164] 2. During use, under the action of toothpaste abrasive, the rolling friction between the drive head and the brush head seat causes wear on the mating surface and also leads to the generation of mating clearance. At this time, the elastic compensation and clearance elimination mechanism will come into play.

[0165] 3. The brush head seat spindle and the spindle fixing frame will also produce a matching gap due to wear under the action of toothpaste abrasive during user use. Due to the existence of the reaction force of the compensation spring, the worn components will be tightened, thus solving the noise caused by the impact of the gap between high-speed moving components.

[0166] 4. The components composed of the rocker arm and the drive head are separated, and there will be tolerances in the actual manufacturing and assembly process, which will cause a fit clearance. At this time, the elastic compensation and anti-backlash mechanism will come into play.

[0167] 5. There will be errors between the theoretical design and the actual manufacturing of the shape. The error will also cause a gap between the convex head and the groove of the brush head seat. At this time, the elastic compensation and clearance elimination mechanism will come into play.

[0168] In summary, the elastic compensation and clearance-eliminating mechanism formed by the compensation spring 48 can effectively stabilize the output angle and torque during the brushing process, reduce noise, and effectively increase the service life.

[0169] It is more preferred that the brush rod moving structure works in the working condition of toothpaste abrasive and grinding liquid for a long time. In addition to the reasonable selection of high wear-resistant materials to make components, the gearing profile of the drive head and the brush head seat should be reasonably designed. In theory, the gearing area should be maximized during the entire motion cycle, which is conducive to reducing the gearing pressure and improving the wear resistance. And the friction between the gearing surfaces should be guaranteed to be rolling friction as much as possible, and the occurrence of sliding friction should be reduced as much as possible, which can better resist the wear resistance.

[0170] In a further preferred embodiment, a conventional involute profile curve is preferred to solve the above problem, and the convex head and the groove 4211 are involute tooth shapes, thereby ensuring that the toothing friction type of the entire process is rolling friction. In order to maximize the toothing area, the maximum modulus and the maximum tooth thickness are selected as much as possible.

[0171] In the embodiment, in addition to using the involute tooth profile to solve the meshing problem between the protrusion and the groove of the toothed brush rod, it can also be expanded to other contour graphics, such as the protrusion is a cylindrical surface and the groove is a trapezoidal surface. Because the utility model is provided with a compensation spring, a constant force can be exerted to push the boss toward the brush head seat. In theory, there is no gap in the meshing of the entire protrusion movement and the groove. However, compared with the involute tooth profile solution, there will be sliding friction in the friction during the movement process, so the theoretical life is weaker than the involute tooth profile solution.

[0172] The implementation method of the drive head and the passive parts discussed in the present invention can be based on actual design requirements, such as Fig. 20A and Fig. 20BIn the embodiment shown, the front end of the driving head 46 can be formed into an active groove 46', and the brush head seat 42 is provided with a corresponding passive boss 4212. The active groove 46' of the driving head 46 can be a single tooth shape or a multi-tooth shape. Such changes in form belong to the scope of the extension of the utility model.

[0173] exist Fig.21A , Fig. 21B In another embodiment, the head of the driving head 46 is formed with a cylindrical protrusion 46", and the brush head seat 42 is provided with a corresponding accommodating groove 4213, and the front end of the cylindrical protrusion 46" is formed in a cylindrical shape.

[0174] exist Fig.22A , Fig. 22B , Fig. 22C and Fig.22D In another embodiment, a U-shaped groove 46 ″′ is formed on the head of the driving head 46 , and a corresponding passive cylinder 4214 is disposed on the brush head seat 42 .

[0175] Among them, the base of the brush head seat 421 is a frame that can accommodate the fixing frame 423. After the fixing frame is correctly installed, it penetrates the brush head base. The rotating shaft 424 and the fixing frame are interference fit without relative movement. The two ends of the rotating shaft 424 are extended and matched with the base gap to form two independent coaxial rotating motion pairs.

[0176] Among them, the safety pin 425 is perpendicular to the axis of the rotating shaft 424, and the rotating brush head assembly is safely locked on the brush rod housing through the horizontal hole on the brush rod housing 41 and the hole on the side of the fixing frame 423. Therefore, the reason for the horizontal device of this safety pin is to prevent the main body from falling vertically, causing the safety pin to be impacted, causing the safety pin hole to be broken, loose, dented... and other unsafe damages, causing the risk of the brush head assembly falling off.

[0177] like Fig.23A and Fig. 23B As shown, Fig.23A This is a schematic diagram of the output shaft of the oscillating motor in the present invention being in a stationary state. Fig. 23B The schematic diagram shows the output shaft swinging left and right, and the output shaft swings around the origin O, P1 and P2 are the extreme swingable positions at both ends, A is the maximum swingable angle, and B represents the arc-shaped motion trajectory formed by the coupling point under the swing. Therefore, the motion trajectory of the power coupling point (output shaft) at the rear end of the swing shaft 53 is an arc circle, which coincides with the center of rotation.

[0178] Among them, Fig.24A and Fig. 24B As shown, Fig.24A This is a schematic diagram of the output shaft being stationary. Fig. 24BThe schematic diagram shows the output shaft swinging left and right. The output shaft in the figure moves in parallel, not in arc swing, which is another example of the oscillating motor mentioned in the utility model. Whether the motor shaft swings or swings in parallel, it can meet the requirements of the toothbrush head driving power source mentioned in the utility model. P1 and P2 are the extreme positions of parallel swinging, and D is the swinging stroke.

[0179] It can be seen that the main working mechanism of the rotating brush rod of the utility model is:

[0180] 1. The main unit of the electric toothbrush provides a reciprocating swing torque through the output shaft. The trumpet-shaped sleeve at the end of the swing rod and the embedded connecting sleeve 49 and the elastic coupling body 45 form a coupling. The output shaft of the main unit and the inner hole of the connecting sleeve 49 and the elastic coupling body 45 made of elastic material realize dynamic coupling, driving the swing rod to swing back and forth.

[0181] 1.1 The middle part of the elastic coupling body 45 is designed as an inner concave ring convex ring 451, and the entire main shaft extends into the inner concave ring convex ring 451 to make linear contact with it, so as to achieve interference-free swinging process and ensure effective power coupling.

[0182] 1.2 The connecting sleeve 49 and the elastic coupling body 45 can also be made of rigid plastic or other materials. The embodiment of the utility model uses elastic materials to effectively absorb the noise generated by the impact force of the swing arm when the output shaft of the host swings and changes direction.

[0183] 1.3 The hardness of the connecting sleeve 49 and the elastic coupling body 45 should be moderate. If the hardness is too low, it will affect the swing arm dynamic coupling effect and sacrifice the final output torque performance of the brush head holder.

[0184] 2. The elastic fulcrum in the middle of the swing rod and the top of the inner bracket constitutes a lever fulcrum. When the coupling swings, the driving head at the other end of the swing rod swings in the opposite direction, and the driving head and the brush head seat cooperate with each other, and finally drive the moving brush head to swing around the central rotating axis.

[0185] 2.1 The elastic fulcrum constituting the fulcrum is provided with a concave ring 441 with an annular convex surface. The minimum diameter of the convex surface of the concave ring 441 is slightly larger than or equal to the outer diameter of the swing rod, so that the swing rod can achieve axial sliding in the hole. The concave ring 441 can effectively prevent the interference of the shaft sleeve and the loss of power when the swing rod swings.

[0186] 2.2 The material of the elastic fulcrum can also be made of rigid plastic. The embodiment of the utility model is specially made of elastic rubber body, the purpose is to use the elastic body to effectively buffer and absorb the noise and abnormal sound caused by the collision of components due to the gap during swinging. The hardness of the elastic fulcrum should be moderate and not too low, otherwise the elastic body will be excessively deformed under heavy load, causing a significant change in the fulcrum position or displacement loss of the swing arm swing stroke, and insufficient power at the end of the swing arm. The embodiment of the utility model preferably uses 80-90 degree nitrile rubber to make the elastic fulcrum.

[0187] 3. In one of the embodiments, the convex head is wrapped by the groove of the brush head seat. When the convex platform swings, the groove is pushed and displaced. Since the brush head seat has a rotating shaft 424 to form a rotating pair, the displacement of the groove is ultimately manifested as the repeated rotation of the brush head driving the bristles on the brush head to rotate and swing.

[0188] 3.1 Theoretically, the ideal state of the boss and the groove should be a gapless fit during the entire reciprocating swing process, and the friction between the surface of the boss and the groove of the brush head seat is rolling friction rather than sliding friction. At this time, the material wear caused by the dynamic coupling is minimal, and the coupling power loss is minimal. The embodiment of the utility model preferably uses the traditional involute tooth shape to achieve the shape envelope of the boss and the groove. Among them, the center of the pitch circle of the boss is the fulcrum of the swing rod, that is, the annular boss of the elastic body at the top of the inner bracket of the brush rod. The central axis of the brush head seat is the center of the pitch circle of the groove of the brush head seat. The ratio of the convex head pitch circle to the brush head seat pitch circle determines the torque conversion ratio of the dynamic coupling, which ultimately affects the swing angle and output torque of the brush head seat. In theory, the distance from the swing rod fulcrum to the boss matching point is proportional to the swing angle of the brush head seat, and inversely proportional to the output torque of the brush head seat.

[0189] 3.2 The boss and the brush head seat groove are involute enveloped, and the entire reciprocating motion matching process is a gap-free match under ideal conditions. Therefore, in theory, the running noise caused by the gap between the boss and the brush head groove can be completely eliminated.

[0190] 3.3 The boss and groove of the utility model can be matched with single teeth or multiple teeth. In the embodiment of the utility model, based on the wear resistance and the applicable swing angle range of the brush head seat, a single boss and a single groove structure of the brush head seat are preferred. The tooth modulus can be maximized to improve the actual strength and wear resistance of the boss.

[0191] 3.4 In the embodiment of the utility model, in order to improve the wear resistance of the boss and the brush head seat, the tooth thickness of the boss is increased as much as possible to reduce the interaction pressure of the surface area. The working space of the thick teeth is reserved in the design.

[0192] 4. The rocker arm mentioned in the present invention is preferably made of a stainless steel bar with good rigidity in the embodiments. During the implementation and verification process, it was found that if the rocker arm is not rigid enough, under the action of high-frequency swinging force, the swing angle will be partially offset due to the flexible resonant deformation of the rocker arm, which will eventually result in a smaller swing angle and output torque of the brush head, thereby losing the expected performance.

[0193] 5. The safety pin of the embodiment of the utility model is perpendicular to the axis of the brush rod, not the traditional coaxial direction, which can effectively prevent the safety pin from being directly impacted by the impact force when the head falls to the ground, causing the safety pin position to collapse toward the main axis of the brush head seat, causing the brush head seat to crack or the safety pin hole to crack, causing the brush head seat to fall off during use. After the safety pin is installed perpendicular to the brush shaft, the above problems can be effectively avoided, and the safety factor of the brush head seat in various working conditions can be improved.

[0194] See also Figure 25 to Figure 28 , showing the oscillating brush rod of the utility model, wherein Fig.25 The overall external schematic diagram of the oscillating brush rod of the utility model is shown. Fig.26 The internal structure diagram of the swing brush rod in the utility model is shown. Fig. 27 The exploded schematic diagram of the swing brush rod in the utility model is shown. Fig.28 A schematic diagram of the gap of the swing brush rod in the utility model is shown.

[0195] The oscillating brush rod of the utility model comprises a brush rod shell 51, an internal bracket 56, an oscillating brush head assembly 52 and an oscillating force transmission assembly. The rear end of the brush rod shell 51 is detachably connected to the electric toothbrush, more specifically to the front end of the main body shell of the electric toothbrush. The brush rod shell 51 is formed in a hollow horn shape, and the rear part thereof is provided with an internal bracket 56 which is also hollow horn-shaped, thereby forming an inner space for a built-in oscillating force transmission assembly. The oscillating brush head assembly 52 is arranged at the front end of the brush rod shell 51, and the rear end of the oscillating force transmission assembly is connected to the output shaft 245 of the oscillating motor 20 of the electric toothbrush, and the front end is connected to the oscillating brush head assembly 52, thereby transmitting the output power of the oscillating motor 20 to the oscillating brush head assembly 52.

[0196] Among them, the oscillating brush head assembly 52 includes a brush rod head 521, a rotating shaft 522, a bristle seat 523 and oscillating bristles 524. The rear end of the brush rod head 521 extends into the front end of the brush rod shell 51 and is rotatably fixed to the internal bracket 56 through the rotating shaft 522. The front end of the brush rod head 521 is fixed with a bristle seat 523, and the bristle seat 523 is implanted with multiple oscillating bristles 524 for cleaning.

[0197] The brush rod head 521 is provided with an axial hole for the rotating shaft 522 to rotate through, and both ends of the rotating shaft 522 extend into the internal bracket 56 to form a swing fulcrum for the brush rod head.

[0198] The swing force transmission component includes a swing shaft 53 and a coupling component. The front end of the swing shaft 53 is embedded in the recessed hole at the rear end of the brush rod head 521, and the rear end is connected to the coupling component, which serves as an output power coupling point. The power drives the coupling point to swing in a swinging manner. The coupling component includes a coupling block 54 and a connecting tube 55. The swing shaft 53 extends into the front end of the connecting tube 55, and the rear end of the connecting tube 55 is connected to the output shaft 245 of the swing motor 20 of the electric toothbrush through the coupling block 54.

[0199] The coupling block 54 is made of elastic material and serves as a passive end, and the connecting pipe 55 is made of rigid material and serves as an active end.

[0200] The movement of the pendulum motor is as follows Fig.23A , Fig. 23B , Fig.24A and Fig. 24B As shown, the swinging process is consistent with the previous one.

[0201] Obviously, the motor output in this way is compatible with the motion trajectory of the coupling point of the toothbrush shaft, and the parallel lines of this reciprocating transformation are perpendicular to the axis of the central axis of the toothbrush body.

[0202] The concave hole at the rear end of the brush rod head 521 and the swing shaft 53 are perpendicular to each other.

[0203] When the output shaft swings, the power is coupled through the coupling assembly, and the brush rod head 521 swings around the rotating shaft at the top of the brush rod inner bracket as a fulcrum. The swing of the swing shaft links the swing of the brush rod head to realize the brushing process.

[0204] The swing trajectory of the output shaft may be an arc or an axis perpendicular to the axis of the main body. Both swing modes can effectively drive the swing axis of the brush rod.

[0205] The coupling assembly preferably adopts an elastic coupling structure, which is composed of a trumpet-shaped connecting pipe 55 and a coupling block 54 in the connecting pipe 55. The coupling block 54 is an elastic body with a through hole, and the output shaft of the oscillating motor is embedded in the elastic body. This special structural design solves two problems:

[0206] 1. The through hole of the elastic body matches the output shaft of the oscillating motor. If the hole and the shaft are both rigidly coupled, wear will inevitably occur under the action of high-frequency swing. The worn hole and the shaft match, and the high-frequency reciprocating impact will produce severe noise. After adopting the elastic coupling design, the reciprocating impact generated after wear is absorbed by the elastic body itself and converted into heat energy for dissipation, effectively solving the noise problem after wear.

[0207] 2. The elastic design of the dynamic coupling point allows for a reasonable interference fit between the shaft and the hole due to the material properties of the elastic body itself. If there is motion interference in the swinging process, the elastic body can rely on its own deformable properties to alleviate the impact of motion interference. Reasonable interference design between the shaft and the hole can effectively increase the service life of the brush rod.

[0208] Therefore, the oscillating brush head assembly can be designed into shapes such as ellipse, circle, rectangle, triangle, etc. according to actual usage requirements.

[0209] Among them, the brush rod shell 51 wraps the moving brush rod head and the swing shaft, effectively reducing the direct contact of the brush rod head with the human mouth, and the discomfort caused to the user by high-speed friction and impact, and effectively reducing the power loss caused by the direct contact of the brush rod head with the human body, thereby improving the swing output efficiency.

[0210] The axial direction of the rotating shaft 522 is perpendicular to the swinging direction of the output shaft.

[0211] The connecting pipe 55 is a trumpet-shaped sleeve.

[0212] The coupling block 54 is a hollow sleeve, and a concave annular convex ring is provided in the middle thereof.

[0213] A compensation pad 57 may also be provided to compensate for the swinging motion.

[0214] Wherein, a brush head protective cap for accommodating the brush rod head extends from the front end of the brush rod housing 51, and the brush head protective cap and the moving brush rod head 521 maintain a distance G (such as Fig.28 The spacing G ensures that there is no friction between the oscillating brush head and the brim of the front section of the brush rod housing, and ensures that all high-speed moving parts work inside the housing, thereby solving the discomfort caused by direct contact of the inner wall of the oral cavity with the high-frequency oscillating brush head during use of a conventional oscillating brush head.

[0215] Preferably, the brush head protective cap is a cap-shaped tongue edge that half encompasses the brush head, which can better accommodate the brush rod head and provide space for its movement.

[0216] Fig.29A , Fig.29B and Fig.29C The schematic diagram of the action of the oscillating electric toothbrush rod with a protective device in the utility model is shown. When the output shaft swings, the power is coupled through the coupling assembly, and the brush rod head 521 swings around the rotating shaft at the top of the bracket inside the brush rod as a fulcrum. The swinging of the swing shaft links the swinging of the brush rod head to realize the brushing process.

[0217] It can be seen that for toothbrush heads with conventional high-frequency oscillation design, the back of the high-frequency oscillating brush head directly rubs against the inner wall of the user's oral cavity during use, and the impact-type contact will cause discomfort to the user. The oscillating brush rod disclosed in the utility model is provided with a brim surrounding the back of the brush head at the front section of the shell, and the size of the brim is determined so as not to affect the maximum swing stroke of the brush head. Due to the presence of the brim, the direct contact between the inner wall of the oral cavity and the high-frequency oscillating brush head can be effectively avoided during use by the user, solving the problem of excessive stimulation of the user by the back of the brush head. The presence of the brim also effectively reduces the pressure of the inner wall of the oral cavity on the moving brush head, making the swing amplitude more stable and effectively reducing the loss of power.

[0218] In summary, the technical content of the utility model combines the advantages of both, realizes the technical feature of a high-frequency reciprocating rotating brush head, overcomes the common defects of high-frequency rotating toothbrushes such as high noise and short life, and the rotation or swing frequency is effectively increased to 350Hz compared to the conventional limit indicator of 133Hz.

[0219] The utility model proposes a flexible compensation technical means to solve the noise and life problems of the brush rod under high-frequency operation.

[0220] The electric toothbrush of the utility model effectively takes into account two modes, which can be adapted to high-frequency rotating brush heads and high-frequency swinging brushes, and realizes the power drive with 140-350Hz high-frequency vibration as the technical feature, meeting the diversified and efficient cleaning needs of users. Moreover, both the swinging and rotating torque working conditions have the characteristics of low noise, simple structure and good economy.

[0221] It is obvious that the above description and record are only examples and are not intended to limit the disclosure, application or use of the utility model. Although the embodiments have been described in the embodiments and described in the drawings, the utility model is not limited to the specific examples of the teachings of the utility model as the best mode currently considered to implement the utility model by the drawings and described in the embodiments, and the scope of the utility model will include any embodiment falling within the previous description and the attached claims.

Claims

1. A high-frequency power multi-mode electric toothbrush, comprising a body shell, an oscillating motor, a rotating brush rod and an oscillating brush rod, wherein the body shell is hollow to form a built-in space, a control circuit board is placed in the body shell and a plurality of function buttons connected to the control circuit board are arranged on the side wall, characterized in that: The built-in space of the body shell is provided with a swing vibration motor, the output shaft of the swing vibration motor extends from the front end of the body shell to provide power output, the swing vibration motor comprises a motor bracket, an electromagnetic coil, a vibration arm assembly, a front cover and a magnet, the front end of the motor bracket is provided with a front cover, the rear end is provided with a magnet, and the rear side of the magnet is also provided with a shock absorbing block, an inner hollow cavity is formed in the motor bracket to accommodate the vibration arm assembly, and the rear outer edge of the inner hollow cavity is covered with an electromagnetic coil; The vibration arm assembly includes a swing arm, a rotating shaft, a bearing and a connecting frame. The rear part of the swing arm is located in the electromagnetic coil at the rear part of the inner hollow cavity. The front part of the swing arm forms a disc portion and the disc portion is provided with an axial hole for the rotating shaft to pass through. Both ends of the rotating shaft are rotatably supported on the motor bracket through bearings. The rear end of the connecting frame covers the front part of the swing arm and forms a cylindrical structure for accommodating the disc portion of the swing arm. The front end of the connecting frame is connected to the rear end of the output shaft to transmit the vibration generated by the vibration arm assembly to the output shaft for output.

2. The high-frequency powered multi-mode electric toothbrush according to claim 1, characterized in that: The swing arm, the rotating shaft and the output shaft are integrally embedded in a connecting frame by secondary plastic injection molding to form a vibration arm assembly. The swing arm is a straight iron swing arm and the rotation axis of the rotating shaft is perpendicular to the swing direction of the swing arm.

3. The high-frequency powered multi-mode electric toothbrush according to claim 1, characterized in that: Both ends of the rotating shaft are provided with shaft shoulders matched with bearings, and the rear end of the output shaft is provided with at least one concave ring, so that the output shaft and the connecting frame are stably formed as one piece after secondary injection molding.

4. The high-frequency powered multi-mode electric toothbrush according to claim 1, characterized in that: The swing arm is formed by stacking high-frequency and low eddy-current loss silicon steel sheets.

5. The high-frequency powered multi-mode electric toothbrush according to claim 1, characterized in that: The rotating brush rod includes a brush rod shell, an inner bracket, a rotating brush head assembly and a power transmission assembly. The inner bracket is arranged in the brush rod shell to form an inner space with a built-in power transmission assembly. The rotating brush head assembly is arranged at the front end of the brush rod shell. The rear end of the power transmission assembly is connected to the output shaft of the oscillating motor, and the front end is connected to the rotating brush head assembly, so as to transmit the output power of the oscillating motor to the rotating brush head assembly.

6. The high-frequency powered multi-mode electric toothbrush according to claim 5, characterized in that: The rotating brush head assembly comprises a brush head seat and rotating bristles. The brush head seat is rotatably arranged in the front end of the brush rod shell, one end of which is planted with a plurality of rotating bristles for cleaning, and the other end is provided with a base connected to the rotating power transmission assembly.

7. The high-frequency powered multi-mode electric toothbrush according to claim 6, characterized in that: The rotary power transmission assembly includes a rocker arm, an elastic fulcrum, an elastic coupling body, a driving head, a compensation spring and a connecting sleeve. The front end of the rocker arm is provided with a driving head extending into the base of the brush head seat. The base of the brush head seat forms a passive part that matches the shape of the driving head. The rocker arm is provided with a compensation spring between the driving head and the elastic fulcrum. The rear end of the rocker arm extends into the front end of the connecting sleeve. The rear end of the connecting sleeve is connected to the output shaft through the elastic coupling body.

8. The high-frequency powered multi-mode electric toothbrush according to claim 1, characterized in that: The oscillating brush rod includes a brush rod shell, an internal bracket, an oscillating brush head assembly and an oscillating force transmission assembly. The internal bracket is arranged in the brush rod shell to form an inner space with a built-in oscillating force transmission assembly. The oscillating brush head assembly is arranged at the front end of the brush rod shell. The rear end of the oscillating force transmission assembly is connected to the output shaft of the oscillating motor, and the front end is connected to the oscillating brush head assembly, so as to transmit the output power of the oscillating motor to the oscillating brush head assembly.

9. The high-frequency powered multi-mode electric toothbrush according to claim 8, characterized in that: The oscillating brush head assembly includes a brush rod head, a rotating shaft, a bristle bundle seat and oscillating bristles. The rear end of the brush rod head extends into the front end of the brush rod shell and is rotatably fixed to the internal bracket through the rotating shaft. The front end of the brush rod head is fixed with a bristle bundle seat, and the bristle bundle seat is planted with multiple oscillating bristles for cleaning.

10. The high-frequency powered multi-mode electric toothbrush according to claim 9, characterized in that: The swing force transmission component includes a swing shaft, a coupling block and a connecting tube. The front end of the swing shaft is embedded in the concave hole at the rear end of the brush rod head, and the rear end extends into the front end of the connecting tube. The rear end of the connecting tube is connected to the output shaft through the coupling block.

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