Wireless brush head type electric toothbrush control method and system based on pulse width modulation

Abstract

The invention relates to the technical field of electric toothbrush control, in particular to a wireless brush head type electric toothbrush control method and system based on pulse width modulation. The method comprises the following steps: firstly outputting an activation carrier signal to enable the receiving module to establish a working power supply, then outputting an emission control pulse to carry out pulse width modulation on the carrier signal, and after wireless transmission by the emission coil L1 and the receiving coil L2, demodulating by the receiving module to obtain a driving control signal so as to control the light emitting module to work, and recording the working time of the brush head.

Description

Technical Field

[0001] This invention relates to the field of electric toothbrush control technology, and in particular to a control method and system for a wireless brush head electric toothbrush based on pulse width modulation. Background Technology

[0002] As electric toothbrushes evolve towards smarter and more multifunctional designs, incorporating light-emitting devices within the brush head to indicate operating mode, brushing status, and replacement reminders has become a common product requirement. In existing solutions, the light-emitting device on the brush head side is typically connected to the control circuitry within the toothbrush body via wires, spring terminals, or conductive contacts to obtain power and receive control signals. However, because the brush head itself needs to be detachable, replaceable, and waterproof, using wires or contacts between the brush head and the toothbrush body can easily lead to structural complexity, assembly difficulties, reduced sealing, and poor contact after prolonged use.

[0003] To address the issue of wire connections, some structures employ electromagnetic coupling to transmit power to the brush head, thus achieving wireless power supply. However, existing wireless power supply solutions typically focus primarily on energy transmission itself, with insufficient consideration given to how to synchronously transmit control information within the same wireless transmission link. As a result, while the brush head can obtain operating power, it is difficult to precisely control the brush head's illumination state based on the toothbrush's control logic, especially hindering functions such as switching between different light modes, combined light emission control, and recording brush head usage status feedback.

[0004] Therefore, a new control method and system are needed to enable the brush head to not only obtain working power without the need for wire connections, but also to stably receive control information, and further achieve precise control over the brush head's light-emitting state and record the brush head's working time.

[0005] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0006] The purpose of this invention is to provide a control method and system for a wireless electric toothbrush based on pulse width modulation, addressing the shortcomings of existing technologies.

[0007] The present invention achieves the above-mentioned objective through the following technical solution: a wireless brush head electric toothbrush control method based on pulse width modulation, comprising: firstly outputting a power supply control signal to enable the transmitting module to enter the working state; then outputting an activation carrier signal and sending the activation carrier signal to the receiving coil L2 inside the brush head through the transmitting coil L1 to enable the receiving module to establish a working power supply; after the receiving module enters the working state, outputting a transmission control pulse, the transmitting module performing pulse width modulation on the carrier signal according to the transmission control pulse, and sending the modulated carrier signal to the receiving coil L2 through the transmitting coil L1; the receiving module extracting electrical energy according to the induced signal received by the receiving coil L2 and completing decoding processing to generate a drive control signal; and the light-emitting module driving the corresponding light-emitting unit to emit light according to the drive control signal.

[0008] This invention also provides a wireless electric toothbrush control system based on pulse width modulation, including a battery power supply module, a control module, a transmitting module, a transmitting coil L1, a receiving coil L2, a receiving module, and a light-emitting module. The battery power supply module provides power to the system; the control module outputs transmitting control pulses and power supply control signals; the transmitting module receives the transmitting control pulses and power supply control signals and outputs a modulated carrier signal; the transmitting coil L1 generates an alternating electromagnetic field based on the modulated carrier signal; the receiving coil L2 receives the alternating electromagnetic field and generates an induced signal; the receiving module extracts electrical energy based on the induced signal and generates a drive control signal; and the light-emitting module drives the corresponding light-emitting unit to emit light according to the drive control signal.

[0009] Furthermore, the transmit control pulse adopts a coding method with a fixed pulse width and distinguishable interval time, and uses the time interval between two adjacent falling edges to represent different data bits, thereby completing the control data transmission while maintaining the carrier power supply function.

[0010] Furthermore, the control data adopts a five-bit data structure, with the first two bits used for baud rate adaptation and the last three bits used for light emission control, thereby enabling the receiving module to selectively drive different light-emitting units according to the received control bits.

[0011] Furthermore, the receiving module can provide feedback on the working status information to the transmitting module during the brush head's operation, and the transmitting module then transmits this feedback information to the control module to achieve cumulative recording of the brush head's working time.

[0012] Furthermore, the transmitting coil L1 is a ring-shaped planar coil structure, the receiving coil L2 is a ring-shaped planar coil structure, and the transmitting coil L1 and the receiving coil L2 are coaxially arranged.

[0013] Furthermore, the transmitting module outputs an activation carrier signal before sending control data, and the receiving module establishes a working power supply based on the activation carrier signal. After the receiving module enters the working state, the transmitting module then sends control data.

[0014] The beneficial effects of this invention are: This invention forms an electromagnetic coupling structure between the transmitting coil L1 and the receiving coil L2, enabling wireless power transmission between the toothbrush body and the brush head. This avoids the problems of complex structure, difficult sealing, and poor long-term contact caused by wire connection, contact connection, or spring connection.

[0015] By having the control module output transmission control pulses and the transmission module perform pulse width modulation on the carrier signal, the same wireless transmission link can transmit control information while transmitting energy, thus solving the problem in traditional wireless power supply schemes that can only supply power but cannot stably transmit control information.

[0016] By setting an active carrier phase, the receiving module establishes a working power supply before receiving subsequent control data, thereby improving the startup stability and decoding reliability of the receiving end and reducing the risk of bit errors.

[0017] Through a five-bit control data structure and a drive control signal generation mechanism, the brush head light-emitting module can selectively and combinedly conduct different light-emitting units, thereby enhancing the electric toothbrush's status indication and mode display capabilities.

[0018] By setting up a feedback code feedback mechanism, the control module can accumulate and record the working time of the brush head, thereby managing the lifespan and replacement status of the brush head.

[0019] In summary, this invention enables stable control and usage status recording of the brush head's light-emitting function based on wireless power supply, thereby improving the functional integrity, structural reliability, and user experience of electric toothbrush products. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the control system of the present invention.

[0021] Figure 2 This is a schematic diagram of the circuit structure of the transmitting module of the present invention.

[0022] Figure 3 This is a schematic diagram of the circuit structure of the receiving module of the present invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It is understood that the accompanying drawings are provided for reference and illustration only, and are not intended to limit the present invention. The connection relationships shown in the accompanying drawings are only for clear description and do not limit the connection method.

[0024] like Figures 1 to 3 As shown, the overall solution of this embodiment includes two parts: the toothbrush body side and the brush head side. The toothbrush body side includes a control module, a transmitting module, and a transmitting coil L1. The brush head side includes a receiving coil L2, a receiving module, and a light-emitting module. The control module has a control signal output terminal for outputting transmitting control pulses and a power supply control signal output terminal for outputting power supply control signals. In this embodiment, the control module is specifically a microcontroller (MCU), which outputs transmitting control pulses and power supply control signals according to the user-input working mode and control strategy. The transmitting module has a control signal input terminal for receiving the transmitting control pulse, a power supply control signal input terminal for receiving the power supply control signal, and a carrier signal output terminal for outputting a modulated carrier signal. The transmitting coil L1 is electrically connected to the carrier signal output terminal and generates an alternating electromagnetic field based on the modulated carrier signal. The receiving coil L2 is positioned opposite to the transmitting coil L1 and forms an electromagnetic coupling structure, used to receive the alternating electromagnetic field and generate an induced signal. The receiving module has a signal input terminal for receiving the induced signal and a drive signal output terminal for outputting a drive control signal; the signal input terminal is electrically connected to the receiving coil L2. The light-emitting module has a drive signal input terminal for receiving the drive control signal. Through this overall structure, the electromagnetic energy and control information output from the toothbrush body can be wirelessly transmitted to the brush head, thereby achieving control of the brush head's light-emitting state without the need for electrical wiring connections.

[0025] like Figure 2As shown, the transmitting module specifically includes a transmitting chip U3, a power control circuit, and a resonant matching circuit. The transmitting chip U3 is specifically a YCS300X RF transmitting control chip, which has a transmit control terminal TX_SEND, a power supply control terminal TX_PWR_EN, and an antenna output terminal ANT. The transmit control terminal TX_SEND serves as the control signal input terminal of the transmitting module, used to receive transmit control pulses from the microcontroller MCU. The power supply control terminal TX_PWR_EN serves as the power supply control signal input terminal of the transmitting module, used to receive power supply control signals from the microcontroller MCU. The antenna output terminal ANT serves as the carrier signal output terminal of the transmitting module, used to output a modulated carrier signal. The power control circuit includes a power control transistor Q1, which has a control terminal and a power supply control terminal. The control terminal is electrically connected to the control path corresponding to the power supply control terminal TX_PWR_EN, and the power supply control terminal is electrically connected to the power supply terminal of the transmitting chip U3, used to control the transmitting chip U3 to enter the working state when the microcontroller MCU outputs a power supply control signal. In this embodiment, when the microcontroller MCU outputs an enable power control signal, the power control transistor Q1 is turned on, and the transmitter chip U3 starts working.

[0026] The resonant matching circuit includes a current-limiting resistor R4, a first filter capacitor C5, a second filter capacitor C10, and a third filter capacitor C11. One end of the current-limiting resistor R4 is electrically connected to the antenna output terminal ANT of the transmitting chip U3, and the other end of the current-limiting resistor R4 is electrically connected to the transmitting coil L1. The first filter capacitor C5, the second filter capacitor C10, and the third filter capacitor C11 are connected in parallel across the two ends of the transmitting coil L1. Through the above connection, the carrier signal output by the transmitting chip U3 is first input to the transmitting coil L1 via the current-limiting resistor R4. The first filter capacitor C5, the second filter capacitor C10, and the third filter capacitor C11, together with the transmitting coil L1, form a resonant network for resonant matching and impedance optimization of the modulated carrier signal, thereby improving the magnetic field stability and wireless power transmission efficiency of the transmitting coil L1 near the target frequency. In this embodiment, the frequency of the carrier signal output by the transmitting chip U3 is 2MHz ± 5%.

[0027] Before transmitting control data, the transmitting module first enters the carrier activation phase. This involves the transmitting chip U3 continuously outputting an activation carrier signal, sending activation energy to the receiving coil L2 via the transmitting coil L1, thus establishing a working power supply for the brush head-side receiving module. When the center distance between the receiving coil L2 and the transmitting coil L1 is 8mm, and the power supply filter capacitors on the brush head side are two 2.2µF capacitors, the activation time required for the receiving module to establish a stable working state is approximately 5 milliseconds. After carrier activation is complete, the microcontroller MCU outputs a transmit control pulse through the transmit control terminal TX_SEND. The transmitting chip U3 performs pulse width modulation on the 2MHz carrier based on this transmit control pulse. The transmit control pulse uses a falling edge interval encoding method, with each falling edge pulse width ranging from 120 to 180 microseconds. The time interval between two adjacent falling edges represents different data bits; 580 to 660 microseconds represents data bit 0, and 900 to 1000 microseconds represents data bit 1. To improve reception reliability, the same set of control data can be repeatedly transmitted, with a time interval greater than 16 milliseconds between two sets of control data.

[0028] like Figure 3 As shown, the receiving module on the brush head side includes a receiving chip U1 and a filtering circuit. The receiving chip U1 is specifically a YCS301S wireless power receiving and signal decoding chip, which has a signal input terminal and a drive signal output terminal. The receiving coil L2 receives the alternating electromagnetic field generated by the transmitting coil L1 and generates an induced signal. In this embodiment, the inductance of the receiving coil L2 is 23.3 microhenries, and it forms a resonant circuit with the resonant capacitor on the brush head side, making the resonant frequency on the receiving side correspond to a 2MHz carrier frequency to improve the wireless power receiving efficiency. The filtering circuit includes a filtering resistor R1 and a first filtering capacitor C5. One end of the receiving coil L2 is electrically connected to one end of the filtering resistor R1, and the other end of the filtering resistor R1 is electrically connected to the signal input terminal of the receiving chip U1. One end of the first filtering capacitor C5 is electrically connected to the other end of the filtering resistor R1, and the other end of the first filtering capacitor C5 is grounded. With the above structure, the induced signal output by the receiving coil L2 first passes through the filter resistor R1, and then the node signal is bypassed by the first filter capacitor C5, thereby suppressing the high-frequency carrier component and retaining the effective control components required for decoding, so that the receiving chip U1 can complete the recovery of control data while extracting working power.

[0029] The light-emitting module includes a first light-emitting unit, a second light-emitting unit, a third light-emitting unit, and a fourth light-emitting unit. In a specific circuit implementation, the first light-emitting unit is specifically a first light-emitting diode (LED1), the second light-emitting unit is specifically a second light-emitting diode (LED2), the third light-emitting unit is specifically a third light-emitting diode (LED3), and the fourth light-emitting unit is specifically a fourth light-emitting diode (LED4). The drive signal output terminal of the receiving chip U1 is electrically connected to the corresponding drive branches of the first light-emitting diode (LED1), the second light-emitting diode (LED2), the third light-emitting diode (LED3), and the fourth light-emitting diode (LED4), respectively, to drive the corresponding light-emitting unit to emit light according to the decoding result. In this embodiment, the control data adopts a five-bit structure, with the first two bits being baud rate adaptive bits and the last three bits being light-emitting control bits. The receiving chip U1 generates the corresponding drive control signal based on the light-emitting control bits. Specifically, when the last three digits are 000, LED1, LED2, and LED3 are off; when the last three digits are 001, LED1 is on; when the last three digits are 010, LED2 is on; when the last three digits are 100, LED3 is on; and when the last three digits are 101, both LED2 and LED3 are on. LED4 corresponds to the red / blue status indicator branch on the brush head side. It can be driven individually or collaboratively by the receiving chip U1 according to the working mode, status indicator conditions, or combined control logic to achieve red / blue status display or to cooperate with other light-emitting units to achieve mode indication.

[0030] In addition to light emission control, this embodiment also includes a brush head working time recording function. Specifically, during brush head operation, the receiving module generates a feedback code based on the working status and transmits the feedback code back to the transmitting module through the receiving coil L2. After receiving the feedback code, the transmitting module forwards it to the control module, which then accumulates and records the brush head working time based on the feedback code. In this embodiment, the control module is specifically a microcontroller (MCU), which accumulates and records the brush head working time based on the feedback code. Through this method, the system can monitor the brush head's usage time, providing a basis for replacement reminders or lifespan management.

[0031] It should be added that the LEDs in the light-emitting module can be red and blue LEDs. The installation of these red and blue LEDs on electric toothbrushes is not for decoration, but to solve the pain points of traditional toothbrushes from the two dimensions of functional care and intelligent management.

[0032] First, these LED lights are the core carrier for achieving multifunctional phototherapy care. As the market's demands for oral care become more refined, simple physical friction is no longer sufficient for users. By integrating red and blue LEDs into the brush head, the toothbrush gains the ability to assist in oral health. In medical principles, specific wavelengths of blue light are often used for teeth whitening and inhibiting certain oral bacteria, while red light is commonly used to relieve gingivitis and promote blood circulation. This solution, through wireless driving technology, allows users to enjoy this optical care while brushing their teeth, greatly enhancing the product's added value.

[0033] Secondly, these lights serve as a visual window for status interaction between the user and the toothbrush. Since this solution supports multiple operating modes, the switching of LED colors, their on / off states, and their intensity adjustments effectively provide feedback to the user on the current operating status. For example, a red light might represent gum care mode, while a blue light represents whitening mode. This intuitive visual feedback allows users to clearly perceive which function they are using, enhancing the product's user experience. Most importantly, these LED lights achieve intelligent management logic through a pulse width modulation-based control method for wireless electric toothbrushes.

[0034] The overall internal logic of this invention can be summarized as follows: First, the control module controls the transmission module to establish transmission conditions. Then, the transmission chip U3 outputs a 2MHz carrier wave and performs pulse width modulation through the transmit control terminal TX_SEND, enabling the carrier wave to simultaneously carry energy and control data. After optimization by the resonant matching circuit, the modulated carrier wave is input to the transmission coil L1. The transmission coil L1 generates an alternating electromagnetic field, which is transmitted to the brush head side through electromagnetic coupling with the receiving coil L2. The receiving coil L2 generates an induced signal. The receiving chip U1 recovers the control information and extracts the working power from the induced signal through a filter circuit composed of a filter resistor R1 and a first filter capacitor C5. Subsequently, based on the decoding result, it outputs a drive control signal to drive the first light-emitting diode LED1, the second light-emitting diode LED2, the third light-emitting diode LED3, and the fourth light-emitting diode LED4 to work. Thus, this invention not only solves the core technical problem of how to achieve power supply and control between the brush head and the toothbrush body under wireless conditions, but also solves several ancillary technical problems such as how to stably transmit control information in a wireless power supply link, how to finely switch the light-emitting mode of the brush head, and how to accurately record the brush head usage time.

[0035] With reference to the accompanying drawings and the above embodiments, the system structure, component connection relationship, signal transmission process, encoding rules and control logic of the present invention have been fully described. Those skilled in the art can implement the technical solution of the present invention without creative effort.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method for a wireless electric toothbrush based on pulse width modulation, characterized in that, Includes the following steps: Power-on procedure: Output power control signal to enable the transmitter module to enter working state; Carrier activation step: Output activation carrier signal and send the activation carrier signal to receiving coil L2 in brush head through transmitting coil L1 so that receiving module establishes working power; Pulse coding step: Output transmission control pulse, which is used to characterize light emission control data; Wireless modulation steps: The carrier signal is pulse-width modulated according to the transmit control pulse, and the modulated carrier signal is transmitted to the receive coil L2 through the transmit coil L1; Receiving and decoding steps: Extract electrical energy from the induced signal received by the receiving coil L2 and demodulate it to obtain the drive control signal; Light emission control steps: Drive the corresponding light emission unit in the light emission module to emit light according to the drive control signal.

2. The wireless electric toothbrush control method based on pulse width modulation according to claim 1, characterized in that, The carrier activation step is performed before the pulse coding step; in the carrier activation step, an activation carrier signal is continuously output first to enable the receiving module to establish working power, and after the receiving module enters the working state, the pulse coding step and the wireless modulation step are then performed.

3. The wireless electric toothbrush control method based on pulse width modulation according to claim 1, characterized in that, The pulse width of the falling edge of the transmit control pulse is 120 microseconds to 180 microseconds. The time interval between two adjacent falling edges is used to represent different data bits. Specifically, 580 microseconds to 660 microseconds represents data bit 0, and 900 microseconds to 1000 microseconds represents data bit 1.

4. The wireless electric toothbrush control method based on pulse width modulation according to claim 3, characterized in that, The light emission control data is five-bit control data, with the first two bits being baud rate adaptive bits and the last three bits being light emission control bits; in the receiving and decoding step, a corresponding drive control signal is generated based on the light emission control bits.

5. The wireless electric toothbrush control method based on pulse width modulation according to claim 1, characterized in that, Following the light emission control step, a time recording step is also included: during the operation of the brush head, a feedback code is output, which is then forwarded by the transmitting module and input into the control module, so that the control module can cumulatively record the brush head operation time based on the feedback code.

6. A wireless electric toothbrush control system based on pulse width modulation, characterized in that, The system for implementing the method of any one of claims 1-5, the system comprising: The battery-powered module is used to provide power to the system; The control module has a control signal output terminal for outputting transmission control pulses and a power supply control signal output terminal for outputting power supply control signals; The transmitting module has a control signal input terminal for receiving the transmitting control pulse, a power supply control signal input terminal for receiving the power supply control signal, and a carrier signal output terminal for outputting a modulated carrier signal; The transmitting coil L1 is electrically connected to the carrier signal output terminal and is used to generate an alternating electromagnetic field according to the modulated carrier signal. The receiving coil L2 is arranged opposite to the transmitting coil L1 and forms an electromagnetic coupling structure, used to receive the alternating electromagnetic field and generate an induced signal; The receiving module has a signal input terminal for receiving the induction signal and a drive signal output terminal for outputting a drive control signal. The signal input terminal is electrically connected to the receiving coil L2. The light-emitting module has a drive signal input terminal for receiving the drive control signal.

7. The wireless electric toothbrush control system based on pulse width modulation according to claim 6, characterized in that, The transmitting module includes a transmitting chip U3, which has a transmit control terminal TX_SEND for receiving the transmit control pulse, a power supply control terminal TX_PWR_EN for receiving the power supply control signal, and an antenna output terminal ANT for outputting the modulated carrier signal. The transmitting module also includes a power control circuit, which is electrically connected to the power supply terminal of the transmitting chip U3 and is used to control the power supply state of the transmitting chip U3.

8. The wireless electric toothbrush control system based on pulse width modulation according to claim 7, characterized in that, The transmitting module further includes a resonant matching circuit, which includes a current-limiting resistor R4, a first filter capacitor C5, a second filter capacitor C10, and a third filter capacitor C11. One end of the current-limiting resistor R4 is electrically connected to the antenna output terminal ANT, and the other end of the current-limiting resistor R4 is electrically connected to the transmitting coil L1. The first filter capacitor C5, the second filter capacitor C10, and the third filter capacitor C11 are respectively connected in parallel to the two ends of the transmitting coil L1.

9. The wireless electric toothbrush control system based on pulse width modulation according to claim 6, characterized in that, The receiving module includes a receiving chip U1 and a filtering circuit. The receiving chip U1 has a signal input terminal for receiving the inductive signal and a drive signal output terminal for outputting the drive control signal. The filtering circuit includes a filter resistor R1 and a first filter capacitor C5. One end of the receiving coil L2 is electrically connected to one end of the filter resistor R1, and the other end of the filter resistor R1 is electrically connected to the signal input terminal of the receiving chip U1. One end of the first filter capacitor C5 is electrically connected to the other end of the filter resistor R1, and the other end of the first filter capacitor C5 is grounded.

10. The wireless electric toothbrush control system based on pulse width modulation according to claim 6, characterized in that, The light-emitting module includes a first light-emitting unit, a second light-emitting unit, a third light-emitting unit, and a fourth light-emitting unit. The first light-emitting unit, the second light-emitting unit, the third light-emitting unit, and the fourth light-emitting unit are respectively connected to the drive signal output terminal. The transmitting coil L1 is disposed at the brush head connection end of the toothbrush body, and the receiving coil L2 is disposed at the bottom of the brush head.

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