Capacitive coupling charging system

Abstract

This application discloses a capacitive coupling charging system for adapting to small wearable devices. The capacitive coupling charging system includes a smart ring and a charging base. The smart ring includes a titanium alloy shell, an elastic conductive component, a receiving circuit, and an energy storage battery. The charging base includes a cavity and a transmitting circuit. At least two insulating slits are formed on the titanium alloy shell, extending along the height of the shell and penetrating its wall thickness, dividing the ring into at least two independent electrical zones, each serving as a different receiving electrode. The receiving electrodes are connected to the receiving circuit via the elastic conductive component, and the receiving circuit is electrically connected to the energy storage battery. Transmitting electrodes are provided on the sidewalls of the cavity, corresponding one-to-one with the receiving electrodes. The transmitting and receiving electrodes cooperate to form a coupling capacitor. The transmitting circuit is installed inside the charging base and electrically connected to the transmitting electrodes.

Description

Technical Field

[0001] This application relates to the field of wireless charging technology, and more particularly to a capacitively coupled charging system. Background Technology

[0002] Currently, wireless charging solutions for smart rings are mainly divided into two categories: contact charging and contactless charging. Contact charging uses a Pogopin probe to connect with the exposed contacts on the ring, which suffers from problems such as contact oxidation and corrosion, damage to the appearance, and poor sealing. Contactless charging is mainly based on inductive coupling (WPT), which transmits energy through magnetic field coupling between a receiving coil inside the ring and a transmitting coil on the charging base. However, the inductive coupling solution requires the placement of magnetic materials (ferrite) around the coil to improve the coupling coefficient, which not only occupies valuable space inside the ring, but the alternating magnetic field generated during operation can also seriously interfere with the magnetic sensors integrated into the ring (such as IMU and magnetometer), affecting the accuracy of posture detection and gesture recognition functions. Capacitively coupled power transfer (CPT), as another contactless energy transmission method, transmits energy through an alternating electric field between the transmitting and receiving plates. It has advantages such as no magnetic field interference and the ability to make the electrodes extremely thin (metal coating), and is gradually gaining attention for use in small wearable devices. Specifically, in existing CPT solutions for smart ring applications, the receiving electrode is typically designed as a separate metal patch or conductive coating, attached to the inner surface of the ring or the inner side of the outer shell, and then connected to the receiving circuit via a flexible circuit board. However, while the aforementioned CPT solution can achieve electric field coupling charging, the receiving electrode needs to be additionally fabricated on the inner surface of the ring, occupying limited internal space. Furthermore, the insulation treatment and precise alignment between the receiving electrode and the shell must be considered, increasing manufacturing steps and costs. Summary of the Invention

[0003] To address the aforementioned technical issues, this application provides a capacitor-coupled charging system for adapting to small-sized wearable devices.

[0004] The technical solution provided in this application is described below:

[0005] This application provides a capacitively coupled charging system, including: a smart ring and a charging dock; The smart ring includes a titanium alloy shell, an elastic conductive component, a receiving circuit, and an energy storage battery; the charging base includes a cavity and a transmitting circuit. At least two insulating seams are provided on the titanium alloy shell. The insulating seams are provided along the height direction of the titanium alloy shell and penetrate the wall thickness of the titanium alloy shell, dividing the titanium alloy annular shell into at least two independent electrical zones, so that the at least two independent electrical zones serve as different receiving electrodes. The receiving electrodes are respectively connected to the receiving circuit through the elastic conductive component, and the receiving circuit is electrically connected to the energy storage battery. The sidewall of the cavity is provided with a transmitting electrode, which corresponds one-to-one with the receiving electrode. The transmitting electrode and the receiving electrode work together to form a coupling capacitor. The transmitting circuit is installed inside the charging base and is electrically connected to the transmitting electrode.

[0006] Optionally, there are two insulating seams, which divide the titanium alloy housing into two independent electrical zones. One of the two independent electrical zones occupies 1 / 3 of the volume of the titanium alloy housing, and the other occupies 2 / 3 of the volume of the titanium alloy housing. The two independent electrical zones serve as two different receiving electrodes.

[0007] Optionally, the number of transmitting electrodes is two, both of which are semi-annular gold-plated copper electrodes, and the size and position arrangement of the two transmitting electrodes correspond one-to-one with the two different receiving electrodes.

[0008] Optionally, the number of insulating seams is three, which divide the titanium alloy shell into three independent electrical zones. The volume of each of the three independent electrical zones occupies 1 / 3 of the volume of the titanium alloy shell, and the three independent electrical zones serve as three different receiving electrodes.

[0009] Optionally, the number of transmitting electrodes is three, and all three transmitting electrodes are semi-circular gold-plated copper electrodes. The size and position arrangement of the three transmitting electrodes correspond one-to-one with the three different receiving electrodes.

[0010] Optionally, the elastic conductive component comprises multiple FPC elastic contacts, the number of which is the same as the number of receiving electrodes, and the multiple FPC elastic contacts are respectively attached to the inner side of the housing of the corresponding receiving electrode.

[0011] Optionally, the transmitting circuit includes a DC input power supply, a Class-E high-frequency inverter drive circuit, and a TX-side resonant matching network; The output terminal of the DC input power supply is electrically connected to the power supply input terminal of the Class-E high-frequency inverter drive circuit, so that the DC input power supply provides DC power to the Class-E high-frequency inverter drive circuit; the signal output terminal of the Class-E high-frequency inverter drive circuit is electrically connected to the input terminal of the TX-side resonant matching network. The TX-side resonant matching network includes a series inductor, one end of which is connected to the signal output terminal of the Class-E high-frequency inverter drive circuit, and the other end is electrically connected to the emitter electrode.

[0012] Optionally, the receiving circuit includes an RX-side resonant matching network, a high-frequency rectifier circuit, an output filter circuit, and a battery charging management chip; The RX-side resonant matching network includes a parallel inductor, and the input terminals of the RX-side resonant matching network are electrically connected to the corresponding elastic conductive components. The parallel inductor is connected in parallel to the signal loop of the RX-side resonant matching network. The output terminal of the RX-side resonant matching network is electrically connected to the input terminal of the high-frequency rectifier circuit. The high-frequency rectifier circuit is a Schottky diode full-bridge rectifier circuit. The output terminal of the high-frequency rectifier circuit is electrically connected to the input terminal of the output filter circuit. The output terminal of the output filter circuit is electrically connected to the input terminal of the battery charging management chip. The output terminal of the battery charging management chip is electrically connected to the energy storage battery.

[0013] Optionally, the interior of the insulating seam is filled with alumina ceramic or epoxy resin; the inner surface of the sidewall of the titanium alloy shell is covered with an anodized layer and a PEEK insulating bottom cover.

[0014] Optionally, the charging dock further includes a magnetic positioning component, which is an N52 neodymium magnet, axially magnetized, and disposed at the bottom of the charging dock in a region away from the transmitting electrode.

[0015] As can be seen from the above technical solutions, this application has the following beneficial effects: This application provides a capacitive coupling charging system that divides the titanium alloy shell of a smart ring into at least two independent electrical zones via insulating seams, which directly serve as receiving electrodes. This eliminates the need for additional independent metal patches or conductive coatings for receiving electrodes, achieving integrated design of the shell and receiving electrodes. Furthermore, a reliable connection between the receiving electrodes and the receiving circuit is achieved through elastic conductive components, allowing the receiving electrodes to correspond one-to-one with the transmitting electrodes on the side wall of the charging base cavity to form coupling capacitors and realize capacitively coupled power transmission. This not only eliminates the manufacturing process of independent receiving electrodes but also solves the problem of independent receiving electrodes occupying valuable space inside the ring, providing more space for the layout of components such as magnetic sensors and energy storage batteries inside the ring. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the capacitor-coupled charging system provided in this application; Figure 2 A schematic diagram of the structure of the titanium alloy shell of the smart ring provided in this application; Figure 3This is a structural schematic diagram of the charging dock provided in this application. Detailed Implementation

[0018] In this application, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and other terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to describe the relative positional relationship between the components or parts and do not specifically limit the specific installation orientation of each component or part.

[0019] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0020] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0021] Furthermore, the structures, proportions, sizes, etc., drawn in the accompanying drawings of this application are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modification to the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects and purposes that this application can produce, should still fall within the scope of the technical content disclosed in this application.

[0022] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] See Figure 1 , Figure 2 and Figure 3 This application first provides an embodiment of a capacitor-coupled charging system, which includes: Smart ring and charging dock; The smart ring includes a titanium alloy shell 01, an elastic conductive component 02, a receiving circuit, and an energy storage battery; the charging base includes a cavity 03 and a transmitting circuit. At least two insulating slits 011 are provided on the titanium alloy shell 01. The insulating slits 011 are provided along the height direction of the titanium alloy shell 01 and through the wall thickness of the titanium alloy shell 01, dividing the titanium alloy annular shell into at least two independent electrical zones, so that the at least two independent electrical zones serve as different receiving electrodes; the receiving electrodes are respectively connected to the receiving circuit through the elastic conductive component 02, and the receiving circuit is electrically connected to the energy storage battery. The side wall of cavity 03 is provided with transmitting electrode 04, which corresponds one-to-one with receiving electrode. The transmitting electrode 04 and receiving electrode work together to form a coupling capacitor. The transmitting circuit is installed inside the charging base and is electrically connected to the transmitting electrode 04.

[0024] The components of this embodiment will be described below: The smart ring primarily consists of a titanium alloy shell 01, an elastic conductive component 02, a receiving circuit, and an energy storage battery, achieving high space utilization and functional integration. The titanium alloy shell 01 is a ring-shaped structure, serving as both the ring's external structural component and one of its energy receiving parts. At least two insulating slits 011 are formed on the titanium alloy shell 01, extending along its height and penetrating the shell's wall thickness. This divides the ring-shaped titanium alloy shell 01 into at least two independent electrical zones, which directly function as different receiving electrodes, eliminating the need for additional independent receiving electrodes. Each receiving electrode is precisely fitted to the elastic conductive component 02. The elastic conductive component 02 acts as an intermediate connecting component, with one end electrically contacting the receiving electrode and the other end establishing a reliable connection with the receiving circuit. The receiving circuit is electrically connected to the energy storage battery, forming a complete energy receiving and storage circuit. Thus, the various components of the smart ring work together to achieve energy reception, processing, and storage functions. Specifically, the receiving electrode formed by the segmentation of the titanium alloy shell 01 is used to form a coupling capacitor with the transmitting electrode 04 of the charging base to receive high-frequency alternating electric field energy transmitted from the outside. The elastic conductive component 02 has good conductivity and elasticity, which can be adapted to the curved structure of the titanium alloy shell 01 to ensure stable electrical conduction between the receiving electrode and the receiving circuit, avoiding poor contact that affects energy transmission. The receiving circuit is used to process the high-frequency AC signal sensed by the receiving electrode through resonance, rectification, and filtering, converting it into stable DC power. The energy storage battery is used to store the power processed by the receiving circuit, providing continuous power to various functional modules of the smart ring. At the same time, the titanium alloy shell 01 realizes the dual functions of a structural component and a receiving electrode, simplifying the overall structure.

[0025] Charging Stand: The charging stand mainly consists of cavity 03 and transmitting circuit, providing precise positioning and stable energy transmission for the smart ring. The internal structure of the charging stand is adapted to the shape and receiving electrode layout of the smart ring. Cavity 03 is a space to accommodate the ring structure of the smart ring. The side wall of cavity 03 is specially equipped with transmitting electrodes 04. The number, shape, and position of the transmitting electrodes 04 correspond one-to-one with the receiving electrodes of the smart ring, ensuring that the transmitting electrodes 04 can be precisely aligned with the receiving electrodes after the smart ring is placed in cavity 03, thus ensuring the formation of coupling capacitor. The transmitting circuit is installed inside the charging stand and establishes a stable electrical connection with the transmitting electrodes 04 on the side wall of cavity 03, forming a complete energy transmission circuit. It can convert externally input electrical energy into high-frequency alternating electric field energy and transmit it to the smart ring through the coupling capacitor. Thus, the various components of the charging base work together to achieve energy conversion, transmission, and positioning functions. Specifically, the cavity 03 not only houses the smart ring, but the transmitting electrode 04 on the side wall of the cavity 03 cooperates with the receiving electrode of the smart ring to form a core structure of capacitive coupling. The air gap between the receiving electrode and the transmitting electrode 04 of the titanium alloy shell 01 forms a coupling capacitor, providing a channel for energy transmission. The transmitting circuit can convert the input DC power into a high-frequency AC signal, driving the transmitting electrode 04 to generate an alternating electric field. The alternating electric field transmits energy to the receiving electrode of the smart ring through the coupling capacitor, realizing contactless charging. At the same time, the structural design of the cavity 03 can physically limit the smart ring, and with the one-to-one correspondence between the transmitting electrode 04 and the receiving electrode, it ensures precise alignment between the two and improves coupling efficiency.

[0026] In this embodiment, the titanium alloy shell 01 of the smart ring is divided into at least two independent electrical partitions by an insulating seam 011, which directly serve as receiving electrodes. There is no need to set up separate metal patches or conductive coating receiving electrodes. From a structural design perspective, the shell and receiving electrodes are integrated into one. Furthermore, the receiving electrodes are reliably connected to the receiving circuit through the elastic conductive component 02. This allows the receiving electrodes to correspond one-to-one with the transmitting electrodes 04 on the side wall of the charging base cavity 03 to form coupling capacitors, realizing capacitive coupling power transmission. This not only eliminates the manufacturing process of independent receiving electrodes but also solves the problem of independent receiving electrodes occupying valuable space inside the ring, providing more space for the layout of components such as magnetic sensors and energy storage batteries inside the ring.

[0027] In an optional embodiment, there are two insulating seams 011, which divide the titanium alloy housing 01 into two independent electrical partitions. The volume of one of the two independent electrical partitions occupies 1 / 3 of the volume of the titanium alloy housing 01, and the volume of the other occupies 2 / 3 of the volume of the titanium alloy housing 01. The two independent electrical partitions serve as two different receiving electrodes.

[0028] In one optional embodiment, there are two transmitting electrodes 04, both of which are semi-annular gold-plated copper electrodes, and the size and position of the two transmitting electrodes 04 correspond one-to-one with two different receiving electrodes.

[0029] In the two optional embodiments described above, two insulating seams 011 are provided along the height direction of the titanium alloy shell 01 and penetrate the shell wall thickness. This structure, through precise cutting and insulation, divides the annular titanium alloy shell 01 into two electrically independent zones, achieving integrated receiving electrodes. Specifically, the two insulating seams 011 are formed using femtosecond laser cutting technology, with the seam width controlled between 0.1 and 0.3 mm, and the insulation dielectric withstand voltage greater than 100V, while ensuring that the mechanical strength of the shell is not compromised. The volume ratio of the two zones is clearly defined, with one zone occupying 1 / 3 of the total volume of the titanium alloy shell 01 and the other occupying 2 / 3. This volume ratio design can adapt to the capacity requirements of the coupling capacitor, ensuring the stability of energy transmission. The two zones serve as two different receiving electrodes, RX+ and RX-, respectively, eliminating the need for additional independent receiving electrodes, thus saving internal space and simplifying the manufacturing process. Two independent electrical partitions serve as receiving components for capacitively coupled charging. They establish a reliable connection with the receiving circuit through the elastic conductive component 02, receiving the alternating electric field energy transmitted by the charging base's transmitting electrode 04. At the same time, relying on the structural characteristics of the titanium alloy shell 01, the appearance integrity and structural strength of the ring are both taken into account.

[0030] Corresponding to the structure of the receiving electrode described above, two semi-annular gold-plated copper electrodes precisely matched with the receiving electrode are used as transmitting electrodes 04 to achieve efficient formation of coupling capacitance and stable energy transmission. Specifically, both transmitting electrodes 04 are made of copper and gold-plated. The gold plating layer can effectively prevent electrode oxidation and extend service life. The electrode thickness is controlled at 0.05~0.15mm to fit the installation space of the charging base cavity 03. The size and position of the two transmitting electrodes 04 correspond one-to-one with the two receiving electrodes. That is, the receiving electrode with a volume ratio of 1 / 3 corresponds to the smaller semi-annular transmitting electrode 04, and the receiving electrode with a volume ratio of 2 / 3 corresponds to the larger semi-annular transmitting electrode 04. The transmitting electrodes 04 are fixedly installed on the side wall of the charging base cavity 03 to ensure that after the smart ring is placed in the cavity 03, the two transmitting electrodes 04 can be precisely aligned with the two receiving electrodes, and the electrode gap is controlled at 0.3~1.0mm. The transmitting electrode 04, together with the receiving electrode, forms two pairs of parallel plate coupling capacitors. It first receives the high-frequency AC signal output by the transmitting circuit and generates an alternating electric field. Through electric field coupling, the electrical energy is transmitted to the receiving electrode. At the same time, the gold-plated material and the precise size and position design effectively improve the coupling efficiency and ensure the stability and reliability of energy transmission.

[0031] In an optional embodiment, there are three insulating seams 011, which divide the titanium alloy housing 01 into three independent electrical zones. The volume of each of the three independent electrical zones occupies 1 / 3 of the volume of the titanium alloy housing 01, and the three independent electrical zones serve as three different receiving electrodes.

[0032] In one optional embodiment, there are two or three transmitting electrodes 04. All three transmitting electrodes 04 are semi-circular gold-plated copper electrodes, and the size and position arrangement of the three transmitting electrodes 04 correspond one-to-one with three different receiving electrodes.

[0033] In the two optional embodiments described above, the structure of the two receiving electrodes and two transmitting electrodes 04 can be further optimized by setting them as three receiving electrodes and three transmitting electrodes 04. Three insulating seams 011 are arranged along the height direction of the titanium alloy shell 01 and penetrate the shell wall thickness. That is, through precise cutting and insulation treatment, the annular titanium alloy shell 01 is divided into three electrically independent zones, achieving integrated receiving electrodes and a three-phase capacitor coupling layout. Specifically, the three insulating seams 011 are formed using femtosecond laser cutting technology, with the seam width strictly controlled between 0.1 and 0.3 mm, and the withstand voltage of the insulating medium is greater than 100V. The three insulating seams 011 are evenly spaced along the circumference of the titanium alloy shell 01, making the three independent electrical zones completely equal in volume. Each zone occupies 1 / 3 of the total volume of the titanium alloy shell 01. This equal volume design ensures that the coupling capacitor capacity of the three receiving electrodes is consistent, adapting to the energy transmission requirements of the three-phase CPT topology. The three zones serve as three different receiving electrodes, eliminating the need for additional independent receiving electrodes. The three independent electrical zones, as the core components of the capacitively coupled charging receiver, first establish a reliable connection with the receiving circuit through the elastic conductive component 02, and then work together to receive the alternating electric field energy transmitted by the three transmitting electrodes 04 of the charging base. At the same time, relying on the structural characteristics of the titanium alloy shell 01, the ring's minimalist appearance, structural integrity, and wearing safety are all taken into account.

[0034] Corresponding to the equal structure of the three receiving electrodes, the transmitting electrodes 04 employ three semi-circular gold-plated copper electrodes precisely matched with the receiving electrodes. This achieves efficient formation of the three-phase coupling capacitor and stable energy transmission, meeting the operational requirements of the three-phase CPT topology. Specifically, all three transmitting electrodes 04 are made of highly conductive copper and gold-plated. The gold plating effectively isolates the electrodes from air, prevents oxidation and corrosion, and extends their lifespan. The electrode thickness is controlled between 0.05 and 0.15 mm, ensuring good conductivity while fitting the installation space of the charging base cavity 03 without occupying additional volume. The size, shape, and position of the three transmitting electrodes 04 correspond one-to-one with the three receiving electrodes. That is, each receiving electrode, accounting for 1 / 3 of the volume, corresponds to a matching semi-circular transmitting electrode 04. The three transmitting electrodes 04 are evenly spaced along the circumferential sidewall of the charging base cavity 03, ensuring that after the smart ring is placed in the cavity 03, the three transmitting electrodes 04 can be precisely aligned with the three receiving electrodes. The electrode gap is strictly controlled between 0.3 and 1.0 mm, ensuring the stable formation of the coupling capacitor. Its core function is to form three pairs of parallel plate coupling capacitors with the three receiving electrodes to receive the three-phase 6.78MHz high-frequency AC signal with a phase difference of 120° output from the transmitting circuit and generate an alternating electric field. Through electric field coupling, the electrical energy is efficiently transmitted to the receiving electrodes. At the same time, the gold-plated material and precise size and position design not only effectively improve the coupling efficiency, but also ensure the balance of three-phase energy transmission, further improving the charging power and stability.

[0035] In an optional embodiment, the elastic conductive component 02 consists of a plurality of FPC elastic contacts, the number of which is the same as the number of receiving electrodes, and the plurality of FPC elastic contacts are respectively attached to the inner side of the housing of the corresponding receiving electrode.

[0036] In this optional embodiment, the elastic conductive component 02 employs multiple FPC elastic contacts, which are precisely matched with the receiving electrodes, meaning that the number of contacts is exactly the same as the number of receiving electrodes. This ensures that each receiving electrode can reliably connect to the receiving circuit through an independent FPC elastic contact. The overall structure is thin, flexible, and perfectly fits the layout requirements of the small space inside the smart ring. Specifically, the FPC elastic contacts use flexible printed circuit boards (FPCs) as the substrate. The substrate has good flexibility and insulation, and can be adapted to the annular curved surface of the titanium alloy housing 01. The contact part is made of a highly conductive material to ensure excellent conductivity. At the same time, the contact integrates an elastic spring structure with a certain amount of expansion and contraction margin. The number of FPC elastic contacts is strictly matched with the number of receiving electrodes. If there are two receiving electrodes, two FPC elastic contacts are set accordingly. If there are three receiving electrodes, three are set accordingly. Each FPC elastic contact is attached to the inner side of the housing of the corresponding receiving electrode. The attachment position is selected from the non-skin-contact area of ​​the receiving electrode and fixed with high-temperature resistant and high-adhesion insulating adhesive. This ensures both the firmness of the attachment and avoids interference with the insulating protective layer of the housing. At the same time, it ensures close contact between the contact and the receiving electrode without contact gaps, ensuring the stability of electrical conduction.

[0037] The flexible FPC contact acts as an intermediate conductive connector between the receiving electrode and the receiving circuit, bridging the gap in energy transmission. It also adapts to the structural characteristics of the smart ring, balancing connection reliability and space utilization. Firstly, the flexible FPC substrate conforms to the curved contours of the titanium alloy shell 01, eliminating the need for significant additional space within the ring and preventing interference with components such as the energy storage battery and receiving circuit, thus meeting the miniaturization requirements of the smart ring. Secondly, the elastic spring structure compensates for minor errors during assembly, ensuring a tight fit between the FPC contact and the receiving electrode. Even slight movement during wearing or charging maintains a stable electrical connection, preventing energy transmission interruptions due to poor contact. Furthermore, each FPC contact independently corresponds to a receiving electrode, allowing for the transmission of high-frequency AC signals sensed by each electrode. This ensures independent and accurate signal transmission, guaranteeing the subsequent receiving circuit's resonance and rectification processing, ultimately achieving efficient and stable capacitively coupled energy transmission.

[0038] In an optional embodiment, the transmitting circuit includes a DC input power supply, a Class-E high-frequency inverter drive circuit, and a TX-side resonant matching network. The output terminal of the DC input power supply is electrically connected to the power input terminal of the Class-E high-frequency inverter drive circuit, so that the DC input power supply provides DC power to the Class-E high-frequency inverter drive circuit. The signal output terminal of the Class-E high-frequency inverter drive circuit is electrically connected to the input terminal of the TX-side resonant matching network. The TX-side resonant matching network includes a series inductor, one end of which is connected to the signal output terminal of the Class-E high-frequency inverter drive circuit, and the other end is electrically connected to the transmitting electrode 04.

[0039] In this optional embodiment, the transmitting circuit consists of three parts: a DC input power supply, a Class-E high-frequency inverter drive circuit, and a TX-side resonant matching network. These components are electrically connected to form a complete circuit, resulting in a compact overall structure suitable for the installation space inside the charging dock. Specifically, the DC input power supply uses a miniaturized, highly stable DC power module; the Class-E high-frequency inverter drive circuit is built using a dedicated high-frequency inverter chip, featuring low switching losses and excellent high-frequency drive performance, suitable for high-frequency signal output in the 6.78MHz ISM band; the TX-side resonant matching network uses a series inductor as its core, employing a high-frequency, low-loss inductor with an inductance value controlled between 0.5-1μH, to meet the capacitive impedance compensation requirements of the coupling capacitor. Furthermore, the output terminal of the DC input power supply is reliably electrically connected to the power input terminal of the Class-E high-frequency inverter drive circuit, ensuring that the DC input power supply can stably provide DC power to the Class-E high-frequency inverter drive circuit; the signal output terminal of the Class-E high-frequency inverter drive circuit is electrically connected to the input terminal of the TX-side resonant matching network to realize the transmission of high-frequency AC signals; one end of the series inductor is tightly connected to the signal output terminal of the Class-E high-frequency inverter drive circuit, and the other end is directly electrically connected to the transmitting electrode 04, establishing a transmission channel for high-frequency signals from the drive circuit to the transmitting electrode 04. All connection nodes are fixed by welding process to ensure reliable contact and no signal loss.

[0040] The aforementioned connection structure converts externally input DC power into a high-frequency AC signal, which is then transmitted to the transmitting electrode 04 after resonant compensation. This provides a stable energy source for capacitively coupled energy transmission while ensuring both efficiency and stability. Specifically, the DC input power supply acts as the energy supplier, continuously outputting stable DC power to ensure the normal operation of the Class-E high-frequency inverter drive circuit and prevent signal distortion due to unstable power supply. The Class-E high-frequency inverter drive circuit performs the core energy conversion function, converting the DC power supplied by the DC input power supply into a 6.78MHz high-frequency AC signal. The output AC voltage amplitude is controlled between 50-200Vpp. This high-frequency, high-voltage signal effectively compensates for the high impedance of the coupling capacitor, ensuring smooth energy transmission through electric field coupling. The series inductance of the resonant matching network on the TX side compensates for the capacitive impedance of the coupling capacitor formed by the transmitting electrode 04 and the receiving electrode. By resonating with the coupling capacitor, it significantly reduces impedance loss during energy transmission and improves energy transmission efficiency. The components work together to enable the transmitting circuit to stably output a high-frequency AC signal that meets the requirements. This signal is transmitted to the transmitting electrode 04 through a series inductor, driving the transmitting electrode 04 to generate an alternating electric field, thus providing a stable energy input to the receiving electrode of the smart ring.

[0041] In an optional embodiment, the receiving circuit includes an RX-side resonant matching network, a high-frequency rectifier circuit, an output filter circuit, and a battery charging management chip. The RX-side resonant matching network includes a parallel inductor, and the input terminals of the RX-side resonant matching network are electrically connected to the corresponding elastic conductive components O2. The parallel inductor is connected in parallel to the signal loop of the RX-side resonant matching network. The output terminal of the RX-side resonant matching network is electrically connected to the input terminal of the high-frequency rectifier circuit. The high-frequency rectifier circuit is a Schottky diode full-bridge rectifier circuit, and the output terminal of the high-frequency rectifier circuit is electrically connected to the input terminal of the output filter circuit. The output terminal of the output filter circuit is electrically connected to the input terminal of the battery charging management chip, and the output terminal of the battery charging management chip is electrically connected to the energy storage battery.

[0042] In this optional embodiment, the receiving circuit mainly consists of four parts: an RX-side resonant matching network, a high-frequency rectifier circuit, an output filter circuit, and a battery charging management chip. These components are electrically connected to form a complete energy processing loop, providing efficient signal processing and stable power output. Specifically, the RX-side resonant matching network uses a parallel inductor as its core. This parallel inductor is a high-frequency, low-loss inductor with an inductance value controlled between 1-2μH, suitable for capacitive impedance compensation and resonant voltage boosting requirements of the receiving end coupling capacitor. The high-frequency rectifier circuit uses a BAT54S Schottky diode to build a full-bridge rectifier structure, featuring small junction capacitance, low forward voltage drop, and fast high-frequency response, suitable for rectifying 6.78MHz high-frequency AC signals. The output filter circuit uses miniaturized surface-mount capacitors to filter out DC voltage ripple after rectification. The battery charging management chip uses a dedicated BQ25125 chip, providing current limiting, constant current / constant voltage charging, and safety protection functions, suitable for the charging requirements of the smart ring's small energy storage battery. The input terminals of the RX-side resonant matching network are reliably electrically connected to the corresponding elastic conductive components 02 to ensure stable reception of high-frequency AC signals induced by each receiving electrode. Parallel inductors are connected in parallel to the signal loop of the RX-side resonant matching network to achieve resonance compensation and signal boosting. The output terminal of the RX-side resonant matching network is electrically connected to the input terminal of the high-frequency rectifier circuit to convert the high-frequency AC signal to a DC signal. The output terminal of the high-frequency rectifier circuit is electrically connected to the input terminal of the output filter circuit to complete DC voltage ripple filtering. The output terminal of the output filter circuit is electrically connected to the input terminal of the battery charging management chip to output a stable DC voltage. The output terminal of the battery charging management chip is electrically connected to the energy storage battery, establishing a stable charging circuit. All connection nodes are also fixed using micro-welding technology to ensure reliable contact and lossless signal and energy transmission.

[0043] The aforementioned connection structure receives the high-frequency AC energy induced by the receiving electrode. After resonance, rectification, filtering, and voltage regulation, it outputs stable DC power to charge the energy storage battery, while ensuring charging safety and efficiency, and providing reliable power supply support for the normal operation of various functional modules of the smart ring. Specifically, the RX-side resonant matching network, serving as the energy receiving and preprocessing unit, compensates for the capacitive impedance of the coupling capacitor formed by the receiving electrode and the transmitting electrode 04 through a parallel inductor, achieving resonance at a frequency of 6.78MHz. This significantly increases the amplitude of the induced voltage at the receiving end, reduces energy transmission loss, and ensures that the high-frequency AC signal can be efficiently transmitted to subsequent circuits. The high-frequency rectifier circuit undertakes the core signal conversion function, converting the resonant high-frequency AC signal into DC voltage through a Schottky diode full-bridge structure. The output DC voltage amplitude is controlled at 5V to meet the subsequent filtering and voltage regulation requirements. The output filter circuit is used to filter out high-frequency ripple and noise in the rectified DC voltage, ensuring a stable output DC voltage and preventing ripple interference with the normal operation of the battery charging management chip. The battery charging management chip, as the core of charging control, regulates the filtered 5V DC voltage to 4.2V, performing current-limiting, constant-current, and constant-voltage charging processes for the energy storage battery. It also has safety protection functions such as overcharge, overcurrent, and overheating protection to prevent damage to the energy storage battery due to abnormal charging. The components work together to enable the receiving circuit to efficiently process the high-frequency energy sensed by the receiving electrodes, converting it into stable and safe DC power to continuously charge the energy storage battery and ensure that the smart ring has sufficient battery life.

[0044] In an optional embodiment, the interior of the insulating seam 011 is filled with alumina ceramic or epoxy resin; the inner surface of the sidewall of the titanium alloy housing 01 is covered with an anodized layer and a PEEK insulating bottom cover.

[0045] In this optional embodiment, the filling content of the insulating seam 011 and the insulating protective structure on the inner surface of the titanium alloy shell 01 are used to ensure electrical isolation of the receiving electrodes, wearing safety, and the structural integrity of the shell. Specifically, the insulating medium filling the insulating seam 011 is selected as alumina ceramic or epoxy resin. The alumina ceramic is filled using a 1600℃ sintering process and then ground smooth, while the epoxy resin is filled using a high-precision potting process. This ensures that the independent electrical zones divided by the titanium alloy shell 01 are completely electrically isolated, that is, the current conduction between each receiving electrode is completely isolated, avoiding short circuits that affect energy transmission. At the same time, it compensates for the structural impact of laser cutting on the shell, ensuring that the mechanical strength at the insulating seam 011 is not lower than that of the shell body, thus strengthening the structural stability of the shell. The inner surface of the side wall of the titanium alloy shell 01 is equipped with a double-layer insulation. The insulation protection design first forms an anodized layer with a thickness of 10-30μm through an anodizing process. This oxide layer uniformly covers the inner side of the shell. Then, a PEEK insulating bottom cover is installed on the outer side of the anodized layer. The PEEK bottom cover is fixed with high-temperature resistant insulating adhesive, forming a double insulation protection with the anodized layer. This does not affect the connection between the elastic conductive component 02 and the receiving electrode, effectively isolating the high-frequency high-voltage signal on the receiving electrode, preventing high-frequency voltage leakage to the human body and causing safety hazards. At the same time, it avoids human contact affecting the electric field distribution of the coupling capacitor, ensuring energy transmission efficiency. The anodized layer can also improve the corrosion resistance of the shell.

[0046] In an optional embodiment, the charging dock further includes a magnetic positioning component, which is an N52 neodymium magnet, axially magnetized, and disposed at the bottom of the charging dock in a region away from the transmitting electrode 04.

[0047] In this optional embodiment, the magnetic positioning component is an N52 neodymium magnet, which has strong magnetic positioning capabilities. Axial magnetization does not interfere with the operation of the transmitting circuit and the distribution of the capacitive coupling electric field. The overall structure is small and adaptable to the installation space at the bottom of the charging base. Specifically, the N52 neodymium magnet is selected with a small size of Φ3×1mm, which ensures sufficient magnetic attraction without occupying too much internal space of the charging base. During installation, it is fixed to the bottom of the charging base and fixed by embedding it into the reserved groove at the bottom of the charging base with high-temperature resistant insulating glue to ensure a firm installation. It is also strictly placed in an area far away from the transmitting electrode 04 to avoid the magnetic field of the magnet interfering with the alternating electric field generated by the transmitting electrode 04, and does not affect the energy conversion and signal output of the transmitting circuit. Through the strong magnetic attraction of the N52 neodymium magnet, the corresponding magnetic structure at the bottom of the smart ring is attracted, guiding the smart ring to be quickly placed into the charging base cavity 03 and accurately positioned. This ensures that the receiving electrode of the ring corresponds one-to-one with the transmitting electrode 04 of the charging base and is precisely aligned, ensuring that the electrode gap is stable within a reasonable range of 0.3~1.0mm, providing alignment support for the stable formation of the coupling capacitor.

[0048] It should be noted that the above description of the disclosed embodiments enables those skilled in the art to implement or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A capacitively coupled charging system, characterized by, The capacitively coupled charging system includes: a smart ring and a charging dock; The smart ring includes a titanium alloy shell, an elastic conductive component, a receiving circuit, and an energy storage battery; the charging base includes a cavity and a transmitting circuit. At least two insulating seams are provided on the titanium alloy shell. The insulating seams are provided along the height direction of the titanium alloy shell and penetrate the wall thickness of the titanium alloy shell, dividing the titanium alloy annular shell into at least two independent electrical zones, so that the at least two independent electrical zones serve as different receiving electrodes. The receiving electrodes are respectively connected to the receiving circuit through the elastic conductive component, and the receiving circuit is electrically connected to the energy storage battery. The sidewall of the cavity is provided with a transmitting electrode, which corresponds one-to-one with the receiving electrode. The transmitting electrode and the receiving electrode work together to form a coupling capacitor. The transmitting circuit is installed inside the charging base and is electrically connected to the transmitting electrode.

2. The capacitively coupled charging system of claim 1, wherein, There are two insulating seams, which divide the titanium alloy shell into two independent electrical zones. One of the two independent electrical zones occupies 1 / 3 of the volume of the titanium alloy shell, and the other occupies 2 / 3 of the volume of the titanium alloy shell. The two independent electrical zones serve as two different receiving electrodes.

3. The capacitively coupled charging system of claim 2, wherein, The number of transmitting electrodes is two, both of which are semi-circular gold-plated copper electrodes. The size and position of the two transmitting electrodes correspond one-to-one with the two different receiving electrodes.

4. The capacitively coupled charging system of claim 1, wherein, There are three insulating seams, which divide the titanium alloy shell into three independent electrical zones. Each of the three independent electrical zones occupies 1 / 3 of the volume of the titanium alloy shell, and the three independent electrical zones serve as three different receiving electrodes.

5. The capacitively coupled charging system of claim 4, wherein, The number of transmitting electrodes is three, and all three transmitting electrodes are semi-circular gold-plated copper electrodes. The size and position of the three transmitting electrodes correspond one-to-one with the three different receiving electrodes.

6. The capacitor-coupled charging system according to any one of claims 1-5, characterized in that, The elastic conductive component consists of multiple FPC elastic contacts, the number of which is the same as the number of receiving electrodes. The multiple FPC elastic contacts are respectively attached to the inner side of the housing of the corresponding receiving electrode.

7. The capacitor-coupled charging system according to any one of claims 1-5, characterized in that, The transmitting circuit includes a DC input power supply, a Class-E high-frequency inverter drive circuit, and a TX-side resonant matching network. The output terminal of the DC input power supply is electrically connected to the power supply input terminal of the Class-E high-frequency inverter drive circuit, so that the DC input power supply provides DC power to the Class-E high-frequency inverter drive circuit; the signal output terminal of the Class-E high-frequency inverter drive circuit is electrically connected to the input terminal of the TX-side resonant matching network. The TX-side resonant matching network includes a series inductor, one end of which is connected to the signal output terminal of the Class-E high-frequency inverter drive circuit, and the other end is electrically connected to the emitter electrode.

8. The capacitor-coupled charging system according to any one of claims 1-5, characterized in that, The receiving circuit includes an RX-side resonant matching network, a high-frequency rectifier circuit, an output filter circuit, and a battery charging management chip. The RX-side resonant matching network includes a parallel inductor, and the input terminals of the RX-side resonant matching network are electrically connected to the corresponding elastic conductive components. The parallel inductor is connected in parallel to the signal loop of the RX-side resonant matching network. The output terminal of the RX-side resonant matching network is electrically connected to the input terminal of the high-frequency rectifier circuit. The high-frequency rectifier circuit is a Schottky diode full-bridge rectifier circuit, and the output terminal of the high-frequency rectifier circuit is electrically connected to the input terminal of the output filter circuit. The output terminal of the output filter circuit is electrically connected to the input terminal of the battery charging management chip, and the output terminal of the battery charging management chip is electrically connected to the energy storage battery.

9. The capacitor-coupled charging system according to any one of claims 1-5, characterized in that, The interior of the insulating seam is filled with alumina ceramic or epoxy resin; the inner surface of the side wall of the titanium alloy shell is covered with an anodized layer and a PEEK insulating bottom cover.

10. The capacitor-coupled charging system according to any one of claims 1-5, characterized in that, The charging dock also includes a magnetic positioning component, which is an N52 neodymium magnet, axially magnetized, and located at the bottom of the charging dock in a region away from the transmitting electrode.

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