A detection end structure and a skin moisture detector

Abstract

This application provides a detection end structure and a skin moisture detector, belonging to the field of human skin detection technology, to solve the problems of inaccurate measurement results caused by poor electrode fit and improper pressure in existing devices. This application features an insulating isolation ring located at the detection end of the housing, preventing parasitic capacitance from the handheld device from coupling to the detection end. A spherical electrode seat is embedded within a ball-and-socket base to form a spherical rotating pair. An electrode cap is located at the distal end of the spherical electrode seat for detecting skin moisture. One end of a conductive spring is electrically connected to the conductive base, and the other end abuts against the proximal surface of the spherical electrode seat. A second elastic element is provided between the conductive springs to maintain contact between the conductive springs and the proximal surface of the spherical electrode seat, maintaining electrical connection during the rotation of the spherical electrode seat. This structure provides an electromagnetic isolation environment through the insulating isolation ring, achieves adaptive fit through the spherical rotating pair, and the conductive springs and the second elastic element work together to form a dynamic self-compensating electrical contact system, ensuring stable transmission of weak capacitive signals throughout the entire stroke of the floating electrode.

Description

Technical Field

[0001] This application belongs to the field of human skin detection technology, specifically relating to a detection end structure and a skin moisture detector. Background Technology

[0002] The moisture content of the stratum corneum is a core indicator for assessing skin barrier function and health. Capacitive sensing, with its non-invasive nature, high sensitivity, and rapid response, has become the mainstream technology for portable skin moisture analyzers. This method is based on a parallel-plate capacitance model, utilizing the capacitive coupling between the detection electrode and the skin surface to achieve quantitative measurement based on the physical property that the dielectric constant of the stratum corneum changes with moisture. As detection accuracy advances to the order of aF, the interface state between the electrode and the skin, as well as the external electromagnetic environment, have an increasingly significant impact on the measurement results.

[0003] Existing portable capacitive skin moisture analyzers typically employ a handheld casing structure, integrating a printed circuit board, main control module, signal processing module, and power supply module, with rigid metal detection electrodes extending from the front. During testing, the user holds the device and presses the electrodes onto the skin surface, relying on subjective feeling to control the pressure and posture. However, the human skin surface is not an ideal plane; it possesses macroscopic curvature determined by the contours of bones and muscles, as well as microscopic undulations composed of skin lines, pores, and microvilli. Rigid electrodes struggle to achieve complete and uniform contact with this complex biological interface, easily resulting in macroscopic tilting or localized poor contact. This leads to uncontrolled edge electric field distribution, making it impossible to define the effective measurement volume, and causing weak signals at the aF level to be overwhelmed by geometric uncertainties. Simultaneously, air trapped in the microscopic depressions of the skin surface forms low-dielectric-constant interlayers, causing drastic dielectric jumps between the electrode and the stratum corneum, further degrading signal fidelity. Operationally, existing devices generally lack effective monitoring and objective feedback of the pressure applied to the electrodes, making it difficult for users to determine whether the pressure applied is appropriate. Excessive pressure compresses or even punctures the stratum corneum, penetrating the measurement depth to the more moisture-rich active epidermal layer, leading to falsely high readings. Insufficient pressure increases contact resistance, resulting in inadequate electric field coupling, causing readings to be low and fluctuate drastically. This uncertainty in pressure introduced by human operation makes it difficult to compare data between different measurements and between different users, severely limiting the clinical and daily application value of aF-level high-precision detection.

[0004] In terms of electromagnetic compatibility, the user's palm, as a large-volume conductor, forms significant parasitic capacitive coupling with the detection electrodes through the device's casing in handheld devices. This parasitic capacitance is typically on the order of hundreds of aF to pF, far exceeding the target signal of the stratum corneum, and varies randomly with the grip area, force, and posture, making it impossible to eliminate through simple calibration. The lack of effective spatial and electrical isolation between the handheld area and the measurement area allows the human body's electric field to directly couple to the measurement front end, further exacerbating signal contamination. The aforementioned multiple technical challenges—such as geometric adaptation of the contact interface, quantitative control of pressure, electromagnetic isolation of the handheld parasitic capacitance, and dynamic tracking of the protective ring—couple together, making it difficult for existing portable skin moisture analyzers to achieve stable and repeatable aF-level high-precision measurements under the complex surface morphology of real human skin and handheld operation conditions.

[0005] Therefore, there is an urgent need for a detection end structure and skin moisture detector that can solve the problem of coordinated mechanical self-adaptation, mechanical sensing and electromagnetic shielding. Summary of the Invention

[0006] In view of this, this application provides a detection end structure and a skin moisture meter to solve the problems of poor electrode adhesion and inaccurate measurement results caused by improper pressure in existing devices.

[0007] To solve the above problems, the technical solution adopted in this application is as follows:

[0008] In a first aspect, this application proposes a detection end structure for detecting skin moisture, disposed within the housing of a skin analyzer and electrically connected to its circuit board. The detection end structure includes an insulating ring and a detection end. The detection end is located inside the distal end of the housing and is used to detect skin moisture. The insulating ring is disposed between the detection end and the housing, and at least partially covers the distal surface and / or peripheral surface of the detection end to block parasitic capacitance of the housing. The detection end includes an integrally formed electrode base and a conductive base. The electrode base has a ball-and-socket seat, and the ball-and-socket seat is embedded with a spherical electrode seat. The spherical electrode seat and the ball-and-socket seat... The spherical electrode holder forms a spherical revolute joint, and an electrode cap is provided at the distal end of the spherical electrode holder. The conductive base is electrically connected to the spherical electrode holder through a conductive component, and the conductive base is also electrically connected to the circuit board. The conductive component includes several sets of conductive springs, one end of which is electrically connected to the conductive base, and the other end of which abuts against the proximal end face of the spherical electrode holder. A second elastic element is provided between the conductive springs. The second elastic element is in a stretched state under normal conditions, so that the several sets of conductive springs remain in contact with the proximal end face of the spherical electrode holder, thereby maintaining the electrical connection with the spherical electrode holder during its rotation.

[0009] Furthermore, the housing is provided with an insulating outer ring, which at least partially covers the outside of the insulating isolation ring; the distal end face of the housing is provided with a detection end shell, which is located on the distal end face of the detection end; the detection end passes through the insulating isolation ring and extends to the detection end shell, and the detection end detects skin moisture through a detection port on the detection end shell.

[0010] Furthermore, the insulating isolation ring includes an insulating inner ring, an insulating front end face, and the first limiting structure; the detection end shell includes the second limiting structure; the detection end shell and the insulating isolation ring are limited and connected by the first limiting structure and the second limiting structure.

[0011] Furthermore, the electrode cap is configured as an arc-shaped electrode cap, with the convex surface of the electrode cap facing the skin; the electrode base is also provided with a micro-bump flexible dielectric layer, which is composited on the surface of the arc-shaped electrode cap facing the skin.

[0012] Furthermore, the electrode base is also provided with a limiting spring, one end of which is fixedly connected to the electrode base, and the other end abuts against the near end face of the spherical electrode base; the end of the conductive spring away from the conductive base is connected to the limiting spring.

[0013] Furthermore, the conductive base is provided with a limiting step at the proximal end of the ball socket, and the limiting spring is disposed on the limiting step.

[0014] Furthermore, a first sealing element is provided between the electrode base and the conductive component, and a second sealing element is provided between the insulating isolation ring and the conductive base.

[0015] Furthermore, a first elastic element is provided between the conductive base and the circuit board, the first elastic element providing an elastic force toward the skin to the detection end so that the detection end fits the skin.

[0016] Furthermore, the first elastic element is a compression spring, the second elastic element is a tension spring, and the conductive spring is a beryllium copper conductive rod.

[0017] Secondly, this application also proposes a skin moisture detector, which includes the detection end structure described in the first aspect, as well as a display screen, a battery, a charging port, and a power switch; a circuit board is provided inside the housing, and the circuit board is electrically connected to the conductive base.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of this application are:

[0019] This application utilizes an insulating isolation ring to provide a clean electromagnetic environment, a spherical rotating pair to provide adaptive fitting capability, a conductive spring to provide a dynamic conductive path, and a second elastic element to provide constant contact force and a self-compensation mechanism. These four elements work together to ensure that, under the complex surface morphology of real human skin and handheld operation conditions, the electrical connection resistance of the spherical electrode holder remains less than 0.1 ohms throughout its entire positive and negative rotational stroke, with no momentary interruptions; the signal transmission standard deviation is small under hand tremor conditions; and the contact performance decays only slightly after long-term wear. This completely solves the problem of electrical connection failure caused by poor contact, wire binding, or wear during the rotation of floating electrodes, achieving high repeatability and high accuracy extraction of aF-level weak capacitance signals, significantly improving the engineering application value and data reliability of skin moisture analyzers. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the 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. Wherein:

[0021] Figure 1 This is a three-dimensional structural diagram of the skin moisture detector provided in the embodiments of this application;

[0022] Figure 2 This is a three-dimensional structural diagram of the skin moisture analyzer provided in the embodiment of this application after removing part of the housing;

[0023] Figure 3 This is a three-dimensional structural diagram of the skin moisture analyzer provided in the embodiment of this application after removing part of the housing and insulating ring;

[0024] Figure 4 This is a longitudinal sectional view of the skin moisture detector provided in an embodiment of this application;

[0025] Figure 5 This is a partial cross-sectional structural schematic diagram of the insulation isolation transformer provided in the embodiments of this application;

[0026] Figure 6 Provided for the embodiments of this application Figure 4 A magnified view of part A.

[0027] Among them, 100 is the shell; 110 is the insulating outer ring;

[0028] 200. Insulating isolation ring; 210. Insulating inner ring; 220. Insulating front end face; 230. First limiting structure;

[0029] 300. Detection end shell; 310. Second limiting structure; 320. Detection port;

[0030] 400, Detection end; 410, Electrode base; 411, Ball socket seat; 420, Conductive base; 430, First elastic element; 440, Spherical electrode seat; 450, Electrode cap; 460, Limiting spring; 471, First sealing element; 472, Second sealing element; 480, Second elastic element; 490, Conductive assembly; 491, Conductive spring;

[0031] 500. Circuit board; 510. Power switch;

[0032] 600. Display screen;

[0033] 700, Battery; 710, Charging port. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0036] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0037] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0038] In this application, unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and do not limit the number of objects; for example, a first object can be one or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0039] Existing portable capacitive skin moisture analyzers typically employ a handheld casing structure, integrating a printed circuit board, main control module, signal processing module, and power supply module, with rigid metal detection electrodes extending from the front. During testing, the user holds the device and presses the electrodes onto the skin surface, relying on subjective feeling to control the pressure and posture. However, the human skin surface is not an ideal plane; it possesses macroscopic curvature determined by the contours of bones and muscles, as well as microscopic undulations composed of skin lines, pores, and microvilli. Rigid electrodes struggle to achieve complete and uniform contact with this complex biological interface, easily resulting in macroscopic tilting or localized poor contact. This leads to uncontrolled edge electric field distribution, making it impossible to define the effective measurement volume, and causing weak signals at the aF level to be overwhelmed by geometric uncertainties. Simultaneously, air trapped in the microscopic depressions of the skin surface forms low-dielectric-constant interlayers, causing drastic dielectric jumps between the electrode and the stratum corneum, further degrading signal fidelity. Operationally, existing devices generally lack effective monitoring and objective feedback of the pressure applied to the electrodes, making it difficult for users to determine whether the pressure applied is appropriate. Excessive pressure compresses or even punctures the stratum corneum, penetrating the measurement depth to the more moisture-rich active epidermal layer, leading to falsely high readings. Insufficient pressure increases contact resistance, resulting in inadequate electric field coupling, lower readings, and significant fluctuations. This uncertainty in force introduced by human operation makes data comparison difficult between different measurements and between different users, severely limiting the clinical and daily application value of aF-level high-precision detection. Regarding electromagnetic compatibility, the user's palm, as a large-volume conductor, forms significant parasitic capacitive coupling with the detection electrodes through the device casing in handheld devices. This parasitic capacitance is typically in the hundreds of aF to pF range, far exceeding the target signal in the stratum corneum, and varies randomly with grip area, force, and posture, making it impossible to eliminate through simple calibration. The lack of effective spatial and electrical isolation between the handheld area and the measurement area allows the human body's electric field to directly couple to the measurement front end, further exacerbating signal contamination. The aforementioned technical issues, such as geometric adaptation of the contact interface, quantitative control of pressure, electromagnetic isolation of handheld parasitic capacitance, and dynamic tracking of the protective ring, are coupled together, making it difficult for existing portable skin moisture analyzers to achieve stable and repeatable aF-level high-precision measurements under the complex surface morphology of real human skin and handheld operation conditions.

[0040] This application utilizes an insulating isolation ring to provide a clean electromagnetic environment, a spherical rotating pair to provide adaptive fitting capability, a conductive spring to provide a dynamic conductive path, and a second elastic element to provide constant contact force and a self-compensation mechanism. These four elements work together to ensure that, under the complex surface morphology of real human skin and handheld operation conditions, the electrical connection resistance of the spherical electrode holder remains less than 0.1 ohms throughout its entire positive and negative rotational stroke, with no momentary interruptions; the signal transmission standard deviation is small under hand tremor conditions; and the contact performance decays only slightly after long-term wear. This completely solves the problem of electrical connection failure caused by poor contact, wire binding, or wear during the rotation of floating electrodes, achieving high repeatability and high accuracy extraction of aF-level weak capacitance signals, significantly improving the engineering application value and data reliability of skin moisture analyzers.

[0041] The following is in conjunction with the appendix Figures 1 to 6 The technical solutions provided in this application will be described in detail through specific embodiments and application scenarios.

[0042] Firstly, such as Figures 2-6 As shown, this application proposes a detection end 400 structure for detecting skin moisture, disposed in the housing 100 of a skin analyzer and electrically connected to its circuit board 500. The detection end 400 structure includes an insulating isolation ring 200 and a detection end 400. The detection end 400 is disposed inside the distal end of the housing 100 and is used to detect skin moisture. The insulating isolation ring 200 is disposed between the detection end 400 and the housing 100, and at least partially covers the distal end surface and / or peripheral surface of the detection end 400 to block the parasitic capacitance of the housing 100. The detection end 400 includes an integrally formed electrode base 410 and a conductive base 420. The electrode base 410 has a ball-and-socket seat 411, and the ball-and-socket seat 411 is embedded with a spherical electrode seat 440. The spherical electrode seat 440 and the ball-and-socket seat... A spherical rotating pair is formed at 411. An electrode cap 450 is provided at the distal end of the spherical electrode seat 440. The conductive base 420 is electrically connected to the spherical electrode seat 440 through a conductive component 490, and the conductive base 420 is electrically connected to the circuit board 500. The conductive component 490 includes several sets of conductive springs 491. One end of the conductive spring 491 is electrically connected to the conductive base 420, and the other end of the conductive spring 491 abuts against the proximal end face of the spherical electrode seat 440. A second elastic element 480 is provided between the conductive springs 491. The second elastic element 480 is in a stretched state under normal conditions so that the several sets of conductive springs 491 remain in contact with the proximal end face of the spherical electrode seat 440, thereby maintaining electrical connection with the spherical electrode seat 440 during rotation.

[0043] Specifically, the detection end 400 is the front-end measuring head assembly of the skin moisture analyzer, used for non-invasive quantitative detection of moisture in the stratum corneum of human skin based on the principle of capacitance. This structure is installed inside the distal end of the detector housing 100 and is electrically connected to the circuit board 500 inside the housing 100, forming a complete detection path from the skin interface to the signal processing module.

[0044] The detection end 400 structure mainly consists of two core components: an insulating isolation ring 200 and the detection end 400 itself. The detection end 400 is located in the internal cavity at the distal end of the housing 100, serving as a functional module for directly performing skin moisture detection. The insulating isolation ring 200 is positioned between the detection end 400 and the housing 100, at least partially covering the distal and peripheral surfaces of the detection end 400. Made of highly insulating materials such as polyetheretherketone (PEEK), the ring forms a high-impedance isolation boundary and an air isolation groove around the detection end 400, preventing the coupling of parasitic capacitance introduced from the handheld area of ​​the housing 100 to the detection end 400. This suppresses the handheld parasitic capacitance from the hundreds of aF level to an extremely low level, thus providing a clean electromagnetic environment for aF-level high-precision capacitance measurement.

[0045] The detection end 400 includes an integrally formed electrode base 410 and a conductive base 420. This two-piece integral molding reduces assembly steps, improves structural coaxiality and sealing reliability, and shortens the signal transmission path. The electrode base 410 contains a ball-and-socket seat 411, within which a spherical electrode seat 440 is embedded. The outer spherical surface of the spherical electrode seat 440 precisely mates with the inner spherical surface of the ball-and-socket seat 411, forming a spherical rotational pair. When the electrode cap 450 contacts the curved surface of the skin, the skin's reaction force drives the spherical electrode seat 440 to rotate relative to the ball-and-socket seat 411 around its center until the end face of the electrode cap 450 is parallel and in contact with the macroscopic contour of the skin. This eliminates the macroscopic tilt angle between the electrode and the skin, ensuring a symmetrical distribution of the edge electric field and preventing distortion of the measurement volume due to tilt.

[0046] An electrode cap 450 is fixedly mounted at the distal end of the spherical electrode holder 440. The electrode cap 450 serves as the effective electrode for capacitance measurement, directly forming a dielectric coupling with the stratum corneum of the skin, converting changes in the dielectric properties of skin moisture into a measurable capacitance signal. The conductive base 420 serves as an electrical transfer hub, electrically connected to the spherical electrode holder 440 via the conductive component 490. Simultaneously, the conductive base 420 is electrically connected to the circuit board 500, forming a continuous electrical path from the electrode cap 450 to the signal processing module of the circuit board 500. This reliably transmits the weak aF-level capacitance signal to the back-end circuit while maintaining the mechanical independence between the detection end 400 and the circuit board 500.

[0047] The conductive component 490 includes several sets of conductive springs 491. One end of each conductive spring 491 is electrically connected to the conductive base 420, and the other end abuts against the proximal surface of the spherical electrode base 440, forming a cantilever beam elastic contact structure. The conductive springs 491 maintain pressure contact with the proximal surface of the spherical electrode base 440 using their own elastic force. When the spherical electrode base 440 rotates, the ends of the springs slide or slightly swing on the proximal surface of the spherical electrode base 440, maintaining continuous electrical contact, providing multiple parallel conductive paths, reducing contact resistance, and improving signal transmission reliability.

[0048] A second elastic element 480 is further provided between the conductive springs 491. Under normal conditions, the second elastic element 480 is always in a stretched, energy-storing state, applying a radially inward contraction force to the conductive springs 491. This tensile force is transmitted through the conductive springs 491 and converted into a normal pressure on the proximal surface of the spherical electrode holder 440, enhancing the contact pressure of the conductive springs 491 and compensating for the attenuation of contact force caused by wear and fatigue. When the spherical electrode holder 440 rotates, the stretched second elastic element 480 adjusts the radial position of each conductive spring 491 in real time, ensuring that the conductive springs 491 fit against the proximal surface of the spherical electrode holder 440 without gaps. This achieves zero-gap dynamic conductivity of the spherical rotating pair, maintaining the stability and repeatability of aF-level signal transmission even under conditions of high-frequency hand vibration or long-term wear, completely solving the problem of electrical connection failure caused by poor contact or wire binding during the rotation of the floating electrode.

[0049] In some implementations, such as Figure 2 , Figure 4 and Figure 5 As shown, the housing 100 is provided with an insulating outer ring 110, which at least partially covers the outer side of the insulating isolation ring 200; a detection end shell 300 is provided on the distal end face of the housing 100, and the detection end shell 300 is located on the distal end face of the detection end 400; the detection end 400 passes through the insulating isolation ring 200 and extends to the detection end shell 300, and the detection end 400 detects skin moisture through a detection port 320 on the detection end shell 300. The insulating isolation ring 200 includes an insulating inner ring 210, an insulating front end face 220, and a first limiting structure 230; the detection end shell 300 includes a second limiting structure 310; the detection end shell 300 and the insulating isolation ring 200 are limited and connected by the first limiting structure 230 and the second limiting structure 310.

[0050] The housing 100 is provided with an insulating outer ring 110, which at least partially covers the outer side of the insulating isolation ring 200. The far end face of the housing 100 is provided with a detection end shell 300, which is located outside the direction of the detection end 400. The detection end 400 passes through the insulating isolation ring 200 and extends to the detection end shell 300. Skin moisture is detected through the detection port 320 on the detection end shell 300. The insulating isolation ring 200 includes an insulating inner ring 210, an insulating front end face 220 and a first limiting structure 230. The detection end shell 300 includes a second limiting structure 310. The detection end shell 300 and the insulating isolation ring 200 are limited and connected by the first limiting structure 230 and the second limiting structure 310. The insulating outer ring 110 covers the insulating isolation ring 200 from the outside, expanding the isolation area and blocking the coupling of the handheld electric field from the side wall of the housing 100 to the detection end 400. The detection end housing 300 serves as the front cover, exposing the electrode cap 450 through the detection port 320, protecting the internal precision structure and providing a standardized measurement window. The insulating front end face 220 of the insulating isolation ring 200 fits against the rear end face of the detection end housing 300, and the first limiting structure 230 and the second limiting structure 310 are engaged to achieve precise axial and radial positioning, ensuring that the width of the air isolation groove between the insulating isolation ring 200 and the detection end housing 300 is constant, preventing assembly misalignment from causing isolation failure, and facilitating front-end disassembly and maintenance.

[0051] In some implementations, such as Figure 6 As shown, the electrode cap 450 is an arc-shaped electrode cap 450, with the convex surface of the electrode cap 450 facing the skin; the electrode base 410 is also provided with a micro-bump flexible dielectric layer, which is composited on the surface of the arc-shaped electrode cap 450 facing the skin.

[0052] The electrode cap 450 is designed as a curved electrode cap 450, with the convex side facing the skin. A micro-bump flexible dielectric layer is also provided within the electrode base 410, composited on the skin-facing surface of the curved electrode cap 450. During detection, the apex of the convex surface of the curved electrode cap 450 preferentially contacts the skin. During gradual downward pressure, air is radially expelled outward, forming a macroscopic curved surface gradient dielectric transition. The micro-bump flexible dielectric layer is a medical-grade conductive silicone film with a Shore hardness of 25A. Its surface array of micro-bumps is embedded in skin texture and pore depressions, displacing residual air. The curved electrode cap 450 significantly reduces the area of ​​residual air, improving contact consistency. The micro-bump flexible dielectric layer smoothly transitions the dielectric difference between air and the stratum corneum with a dielectric constant of 5 to 8. The dual synergy of the macroscopic curved surface gradient and the microscopic dielectric gradient significantly improves the coupling efficiency and repeatability of the aF-level weak electric field signal.

[0053] In some implementations, such as Figure 3 and Figure 6As shown, the electrode base 410 is also provided with a limiting spring 460. One end of the limiting spring 460 is fixedly connected to the electrode base 410, and the other end abuts against the near end face of the spherical electrode base 440. The end of the conductive spring 491 away from the conductive base 420 is connected to the limiting spring 460.

[0054] The electrode base 410 is also provided with a limiting spring 460. One end of the limiting spring 460 is fixedly connected to the electrode base 410, and the other end abuts against the near end face of the spherical electrode seat 440. The end of the conductive spring 491 away from the conductive base 420 is connected to the limiting spring 460. The limiting spring 460 serves as an intermediate transition member. Its root is fixed to the electrode base 410, and its end face abuts against the near end face of the spherical electrode seat 440. The conductive spring 491 indirectly applies abutment force to the spherical electrode seat 440 through the limiting spring 460. The limiting spring 460 provides a large area of ​​elastic contact surface, evenly dispersing the contraction force of the conductive spring 491 and avoiding single-point stress concentration and slippage. At the same time, it restricts the axial movement of the spherical electrode seat 440 towards the conductive base 420, providing axial elastic limitation for the spherical electrode seat 440, ensuring stable operation of the spherical rotating pair within a set range, and compensating for the wear of the conductive spring 491.

[0055] When the spherical electrode holder 440 is in the middle position, the tensile force of the second elastic element 480 causes the conductive spring 491 to contract and converge radially inward. The ends of the conductive spring 491 are evenly distributed through the limiting spring 460 and abut against the near end face of the spherical electrode holder 440, forming a multi-point contact parallel conductive path. The limiting spring 460 maintains its flatness under the clamping force of the second elastic element 480, ensuring that the abutting pressure of each conductive spring 491 is balanced.

[0056] When the curved electrode cap 450 contacts the curved surface of the skin, the skin's reaction force drives the spherical electrode seat 440 to rotate relative to the ball-and-socket seat 411, causing the proximal surface of the spherical electrode seat 440 to tilt or slightly move. At this time, the end of the conductive spring 491 slides on the proximal surface of the spherical electrode seat 440, and the second elastic element 480 adjusts the radial spacing of each conductive spring 491 in real time to compensate for the change in the contact point position caused by the tilt of the proximal surface, so that the conductive spring 491 always contracts inward and remains in contact; the limiting spring 460 swings slightly with the conductive spring 491 as a whole, and its large-area elastic contact surface adapts to the angle change of the proximal surface, avoiding stress concentration at a single point.

[0057] When a hand trembles, the spherical electrode holder 440 vibrates at high frequency within the ball socket 411. The tensile energy storage characteristics of the second elastic element 480 provide dynamic damping, suppressing the tendency for separation between the conductive spring 491 and the proximal end face of the spherical electrode holder 440. The elastic limiting effect of the limiting spring 460 prevents the spherical electrode holder 440 from axially disengaging, and the cantilever elasticity of the conductive spring 491 absorbs radial impact. The three elements work together to keep the electrical contact stable under dynamic disturbances, without momentary interruption or arcing.

[0058] When prolonged use causes wear at the end of the conductive spring 491, the constant tensile force of the second elastic element 480 automatically compensates for the wear gap, driving the conductive spring 491 to further contract radially and maintain constant contact pressure; the elastic deformation reserve of the limiting spring 460 provides additional stroke to ensure effective contact is maintained during wear compensation. The three elements work together to achieve a self-compensating long-life design without the need for manual adjustment.

[0059] Therefore, the limiting spring 460 provides axial limiting and elastic support platform, the conductive spring 491 provides multiple parallel conductive paths, and the second elastic element 480 provides radial contraction force and dynamic compensation. These three elements, together with the proximal surface of the spherical electrode holder 440, form an elastic adaptive electrical contact system. The core effect of this system is that: the electrical connection resistance of the spherical electrode holder 440 is always less than 0.1 ohms throughout its full rotation stroke (±5 degrees), with no momentary interruption; under human hand tremor conditions of 8 to 12 Hz, the signal transmission standard deviation is less than 5 aF; and after long-term wear, the contact performance decay is less than 10%. This completely solves the problem of electrical connection failure caused by poor contact, wire binding, or wear during the rotation of the floating electrode, providing a stable and reliable dynamic electrical path for aF-level high-precision capacitance measurement.

[0060] In some implementations, such as Figure 6 As shown, the conductive base 420 has a limiting step near the ball socket 411, and the limiting spring 460 is disposed on the limiting step.

[0061] The conductive base 420 has a limiting step near the ball socket 411, and the limiting spring 460 is located on the limiting step. The limiting step is an annular shoulder integrally formed by the conductive base 420, perpendicular to the axis of the housing 100, and provides a rigid support reference for the root of the limiting spring 460. The limiting step prevents the limiting spring 460 from collapsing or undergoing inelastic deformation in the direction of the ball socket 411 under the reaction force of the spherical electrode seat 440, ensuring that the limiting spring 460 and the near end face of the spherical electrode seat 440 always maintain a constant abutment pressure, maintaining the consistency of axial limiting accuracy and elastic reset.

[0062] In some implementations, such as Figure 4 and Figure 5As shown, a first sealing element 471 is provided between the electrode base 410 and the conductive component 490, and a second sealing element 472 is provided between the insulating isolation ring 200 and the conductive base 420.

[0063] A first seal 471 is provided between the electrode base 410 and the conductive component 490, and a second seal 472 is provided between the insulating isolation ring 200 and the conductive base 420. The first seal 471 fills the annular gap between the inner wall of the electrode base 410 and the outer wall of the conductive component 490, sealing the front cavity of the ball socket 411; the second seal 472 is disposed between the inner wall of the insulating isolation ring 200 and the outer cylindrical surface of the conductive base 420, blocking the fluid channel between the front cavity of the detection end shell 300 and the inner cavity of the housing 100. The first seal 471 protects the spherical rotating pair from grease contamination and maintains the low friction characteristics of the PTFE anti-friction ring; the second seal 472 prevents sweat from the skin contact area from seeping into the interior of the housing 100 along the inner hole of the insulating isolation ring 200 and corroding the circuit board 500, while maintaining the electrical isolation performance of the inner hole of the insulating isolation ring 200 and ensuring the long-term reliability of the airtight shielded floating cavity.

[0064] In some implementations, such as Figure 4 As shown, a first elastic element 430 is provided between the conductive base 420 and the circuit board 500. The first elastic element 430 provides an elastic force toward the skin to the detection end 400 so that the detection end 400 fits against the skin.

[0065] A first elastic element 430, which is a compression spring, is provided between the conductive base 420 and the circuit board 500 to provide an elastic force toward the skin to the detection end 400. The two ends of the compression spring abut against the rear end of the conductive base 420 and the front end of the circuit board 500, respectively. It is in a compressed, energy-storing state in the axial direction of the housing 100, continuously applying a pushing force toward the skin to the detection end 400. The first elastic element 430 ensures that the detection end 400 is always subjected to a pre-tightening force toward the skin during measurement, maintaining a stable fit between the electrode cap 450 and the skin without the user needing to press hard. Simultaneously, it allows the detection end 400 to slightly retract when subjected to skin reaction force, forming an elastic floating buffer, reducing the impact of fluctuations in manual pressure on measurement repeatability, and avoiding systematic errors caused by overpressure or underpressure.

[0066] In some embodiments, the first elastic element 430 is a compression spring, the second elastic element 480 is a tension spring, and the conductive spring 491 is a beryllium copper conductive rod.

[0067] The first elastic element 430 is a compression spring, the second elastic element 480 is a tension spring, and the conductive spring 491 is a beryllium copper conductive rod. The compression spring utilizes a helical structure to provide linear restoring force during axial compression; the tension spring utilizes a hook-and-loop structure to provide constant inward contraction force during radial tension; the beryllium copper conductive rod utilizes the high elastic modulus and excellent conductivity of beryllium copper alloy to maintain low contact resistance under slight deformation. The linear elastic force characteristic of the compression spring ensures stable and controllable contact force at the detection end 400, avoiding pressure abrupt changes caused by nonlinear elastic elements; the constant tension characteristic of the tension spring ensures that the conductive spring 491 maintains constant contact pressure throughout the entire rotation stroke of the spherical electrode seat 440, without loosening due to changes in rotation angle; the beryllium copper conductive rod has a high elastic limit and is fatigue-resistant, ensuring reliable electrical connection under long-term reciprocating rotation, with a contact resistance consistently less than 0.1 ohms.

[0068] like Figures 1-6 As shown, this application also proposes a skin moisture detector, including the aforementioned detection end 400 structure, as well as a display screen 600, a battery 700, a charging port 710, and a power switch 510. A circuit board 500 is housed within the housing 100, and the circuit board 500 is electrically connected to the conductive base 420. The battery 700 supplies power to the circuit board 500 and the detection end 400, the charging port 710 replenishes the battery 700 with power, the power switch 510 controls the on / off state of the entire device, and the display screen 600 receives and visualizes the moisture content data output by the main control module of the circuit board 500. The weak aF-level capacitance signal detected by the detection end 400 is transmitted to the circuit board 500 via the conductive base 420, where it is amplified, converted from analog to digital, and processed by the signal processing module on the circuit board 500, ultimately converting it into a skin moisture percentage or relative value. This constitutes a portable skin moisture detection system that can operate independently. The aF-level high-precision measurement capability of the detection end 400 is converted into quantitative skin moisture data that users can read in real time through signal processing on the circuit board 500 and intuitive presentation on the display screen 600. The whole machine has a compact structure and is easy to operate by hand. The electromagnetic isolation design of the insulating isolation ring 200 and the insulating outer ring 110 ensures that stable and repeatable measurement results can still be obtained under real handheld conditions. It is suitable for large-scale application and promotion in medical clinical, beauty and skin care and home health monitoring.

[0069] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0070] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0071] The above description of the disclosed embodiments enables those skilled in the art to make 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 spirit or 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.

[0072] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

Claims

1. A detection end structure for detecting skin moisture, characterized in that: The detection end structure includes an insulating isolation ring (200) and a detection end (400) disposed in the housing (100) of the skin detector and electrically connected to its circuit board (500). The detection end (400) is located inside the distal end of the housing (100) and is used to detect skin moisture. The insulating isolation ring (200) is disposed between the detection end (400) and the housing (100), and at least partially covers the distal end face and / or peripheral side face of the detection end (400) to block the parasitic capacitance of the housing (100); The detection end (400) includes an integrally formed electrode base (410) and a conductive base (420). The electrode base (410) is provided with a ball socket (411), and a spherical electrode seat (440) is embedded in the ball socket (411). The spherical electrode seat (440) and the ball socket (411) form a spherical rotation pair. An electrode cap (450) is provided at the distal end of the spherical electrode seat (440). The conductive base (420) is electrically connected to the spherical electrode base (440) through a conductive component (490), and the conductive base (420) is electrically connected to the circuit board (500); The conductive component (490) includes several sets of conductive springs (491), one end of the conductive spring (491) is electrically connected to the conductive base (420), and the other end of the conductive spring (491) abuts against the near end face of the spherical electrode base (440); A second elastic element (480) is provided between the conductive springs (491). The second elastic element (480) is in a stretched state under normal conditions so that the conductive springs (491) remain in contact with the near end face of the spherical electrode seat (440) and thus maintain electrical connection with the spherical electrode seat (440) during the rotation of the spherical electrode seat (440).

2. The detection end structure according to claim 1, characterized in that: The housing (100) is provided with an insulating outer ring (110), which at least partially covers the outside of the insulating isolation ring (200); the housing (100) is provided with a detection end shell (300) on its distal end face, which is located on the distal end face of the detection end (400); the detection end (400) passes through the insulating isolation ring (200) and extends to the detection end shell (300), and the detection end (400) detects skin moisture through the detection port (320) on the detection end shell (300).

3. The detection end structure according to claim 1, characterized in that: The insulating isolation ring (200) includes an insulating inner ring (210), an insulating front end face (220), and the first limiting structure (230); the detection end shell (300) includes the second limiting structure (310); the detection end shell (300) and the insulating isolation ring (200) are limited and connected by the first limiting structure (230) and the second limiting structure (310).

4. The detection end structure according to claim 1, characterized in that: The electrode cap (450) is configured as an arc-shaped electrode cap (450), with the convex surface of the electrode cap (450) facing the skin; the electrode base (410) is also provided with a micro-bump flexible dielectric layer, which is composite on the surface of the arc-shaped electrode cap (450) facing the skin.

5. The detection end structure according to claim 1, characterized in that: The electrode base (410) is also provided with a limiting spring (460), one end of which is fixedly connected to the electrode base (410), and the other end abuts against the near end face of the spherical electrode base (440); the end of the conductive spring (491) away from the conductive base (420) is connected to the limiting spring (460).

6. The detection end structure according to claim 5, characterized in that: The conductive base (420) has a limiting step near the ball socket (411), and the limiting spring (460) is located on the limiting step.

7. The detection end structure according to claim 1, characterized in that: A first seal (471) is provided between the electrode base (410) and the conductive component (490), and a second seal (472) is provided between the insulating isolation ring (200) and the conductive base (420).

8. The detection end structure according to claim 1, characterized in that: A first elastic element (430) is provided between the conductive base (420) and the circuit board (500). The first elastic element (430) provides an elastic force toward the skin to the detection end (400) so that the detection end (400) fits against the skin.

9. The skin moisture analyzer according to any one of claims 1-8, characterized in that: The first elastic element (430) is a compression spring, the second elastic element (480) is a tension spring, and the conductive spring (491) is a beryllium copper conductive rod.

10. A skin moisture analyzer, characterized in that: It includes a detection end structure as described in any one of claims 1 to 9, as well as a display screen (600), a battery (700), a charging port (710) and a power switch (510); a circuit board (500) is provided inside the housing (100), and the circuit board (500) is electrically connected to the conductive base (420).

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