Card thickness detection equipment

Abstract

The utility model discloses a card thickness detection device, which comprises a frame body, a conveyor belt module, a roller detection module, an elastic support module, a damping module, a displacement detection unit and a data processing module, and is characterized in that the elastic support module and the roller detection module act synergistically, so that a roller is contacted with the surface of a card and is jacked up when the card passes through; the elastic supporting module and the damping module cooperate to limit the jumping height of the roller, so that the reset time of the roller is less than or equal to 0.1 second after a single card passes, and the equipment achieves high-precision thickness detection and 0.1-second rapid reset matched critical damping design through the cooperation of elastic supporting and hydraulic damping, and gives consideration to the response speed and stability. The composite supporting structure effectively filters high-frequency vibration and conveyor belt disturbance, adapts to 0.5-2m / s variable-speed operation, and remarkably improves the detection efficiency.

Description

Technical Field

[0001] This utility model relates to the field of detection technology, specifically to a card thickness detection device. Background Technology

[0002] In the field of automated processing, especially in the card processing, inspection, and packaging industry, accurate and continuous measurement of card thickness is a crucial step in ensuring product quality and production efficiency. The consistency of card thickness, such as that of ID cards, bank cards, and membership cards, directly affects their usability, durability, and subsequent processing techniques, such as printing and lamination. However, in traditional technologies, measuring card thickness often faces numerous challenges, including:

[0003] Low inspection efficiency: Traditional card thickness inspection methods often employ intermittent measurement, requiring multiple inspection points on the production line or measurement when the card is stationary. This not only reduces the overall operating efficiency of the production line but also increases inspection costs and time.

[0004] Slow reset speed: During continuous testing, the testing mechanism needs to reset frequently to prepare for the next measurement. The reset process of traditional mechanisms is often complex, involving the coordinated movement of multiple mechanical parts, resulting in a slow reset speed, which affects the continuity and accuracy of testing.

[0005] Given the above shortcomings, the industry urgently needs a mechanism that can quickly reset and continuously and accurately detect card thickness. Summary of the Invention

[0006] In order to overcome the shortcomings of existing technical solutions, this utility model provides a card thickness detection device, which can effectively solve the problem of low card detection efficiency mentioned in the background technology.

[0007] The technical solution adopted by this utility model to solve its technical problem is: a card thickness detection device, including a frame, comprising:

[0008] Conveyor belt module: Used for continuous card transport, located at the bottom of the frame, including the conveyor belt body and drive mechanism;

[0009] Roller detection module: Located above the conveyor belt, it includes at least one roller;

[0010] Elastic support module: Connected above the roller detection module, it includes elastic elements to provide elastic restoring force when the roller is compressed;

[0011] Vibration damping module: Located between the elastic support module and the roller detection module, it is used to suppress the vertical vibration of the roller;

[0012] Displacement detection unit: electrically connected to the roller detection module, it measures the vertical displacement of the roller relative to its initial position in real time, and the displacement corresponds to the card thickness;

[0013] Data processing module: Receives signals from the displacement detection unit and outputs card thickness data through a pre-calibrated displacement-thickness relationship model;

[0014] The elastic support module works in conjunction with the roller detection module to make the roller contact the card surface and be lifted up when the card passes through. The elastic support module works in conjunction with the shock absorption module to limit the roller's jumping height, so that the roller's reset time after a single card passes through is ≤0.1 seconds.

[0015] Furthermore, the roller detection module includes multiple rollers arranged in parallel along the conveyor belt travel direction, with a spacing of 10~50mm between each roller, covering the entire surface area of ​​the card.

[0016] Furthermore, the elastic support module is at least one of a compression spring, a disc spring, or a pneumatic elastomer, with a stiffness coefficient of 300~1000 N / m.

[0017] Furthermore, the damping module is at least one of a hydraulic damper, a magnetorheological damper, or a viscous damper, with a damping coefficient of 30~100 N·s / m.

[0018] Furthermore, the displacement detection unit is at least one of a laser displacement sensor, a capacitive displacement sensor, or a magnetic grating ruler, with a resolution ≤0.01mm.

[0019] Furthermore, the conveyor belt module is provided with adjustable limit baffles on both sides, the baffle spacing is adapted to the card width ±1mm, and the surface friction coefficient of the conveyor belt is ≥0.6.

[0020] Furthermore, the surface of the roller is covered with an elastic material layer with a Shore hardness of 20A~60A and a thickness of 1~5mm.

[0021] Furthermore, the data processing module integrates an anomaly detection algorithm, which triggers a stop signal when the detection interval between two consecutive cards is less than 0.1 seconds or the thickness mutation value is greater than 50% of the nominal value.

[0022] Compared with the prior art, the beneficial effects of this utility model are:

[0023] The vibration damping module effectively filters out high-frequency vibrations >10Hz, and combined with the constant contact pressure (2-5N) of the elastic support, it reduces the standard deviation of thickness detection to within ±0.005mm, meeting the needs of high-precision industrial testing.

[0024] The elastic support module provides constant contact force, avoiding measurement deviations caused by pressure fluctuations in traditional mechanical contact measurements and ensuring stable contact between the roller and the card surface.

[0025] The elastic element (such as a compression spring) resets within 0.1 seconds after the card passes through, forming an underdamped system (damping ratio ζ≈1) in conjunction with the hydraulic damper. This achieves a balance between rapid response and overshoot suppression under critical damping conditions, ensuring continuous detection efficiency.

[0026] The composite support structure (spring + damper) is not sensitive to conveyor belt vibration (amplitude ≤ 0.3 mm) and can still maintain the stability of the measurement benchmark in the 0.5-2 m / s variable speed operation scenario.

[0027] When the card has creases or foreign objects, the elastic support can absorb an instantaneous impact force of >50N. Combined with the energy dissipation mechanism of the shock absorption module, it prevents the roller assembly from being damaged by hard collisions and extends the life of the equipment.

[0028] The modular design eliminates the need for recalibration when the conveyor belt speed changes, maintaining measurement stability and reducing maintenance costs.

[0029] The vibration damping module filters out high-frequency mechanical vibration noise, ensuring that the displacement detection unit obtains a stable signal and avoiding false triggering or data fluctuations.

[0030] After the displacement-thickness relationship model is pre-calibrated, the data processing module can output thickness data in real time, supporting online quality monitoring and feedback. Attached Figure Description

[0031] Figure 1 This is a three-dimensional structural view of the present invention;

[0032] Figure 2 This is a schematic diagram of the roller detection module, elastic support module, shock absorption module, data processing module and displacement detection unit of this utility model;

[0033] Figure 3 for Figure 2 Enlarged view of structure A in the image;

[0034] Figure 4 This is a flowchart illustrating the process of this utility model.

[0035] Numbering on the map:

[0036] 1-Conveyor belt module, 2-Roller detection module, 3-Elastic support module, 4-Shock absorption module, 5-Displacement detection unit, 6-Data processing module, 7-Limit baffle, 8-Frame, 11-Conveyor belt body, 12-Drive mechanism, 21-Roller, 22-Elastic material layer, 31-Elastic element. Detailed implementation method.

[0037] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0038] The following specific examples illustrate the implementation of this disclosure. Those skilled in the art can easily understand other advantages and effects of this disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. This disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this disclosure. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure. Example

[0039] like Figure 1-4 As shown, this utility model provides a card thickness detection device, including a frame 8, comprising:

[0040] Conveyor Module 1: Used for continuous card transport, located at the bottom of the frame 8, including the conveyor body 11 and the drive mechanism 12;

[0041] Roller detection module 2: Located above the conveyor belt, it includes at least one roller 21;

[0042] Elastic support module 3: Connected above the roller detection module 2, including elastic element 31, used to provide elastic restoring force when the roller 21 is compressed;

[0043] Vibration damping module 4: Located between elastic support module 3 and roller detection module 2, it is used to suppress the vertical vibration of roller 21;

[0044] Displacement detection unit 5: Electrically connected to roller detection module 2, it measures the vertical displacement of roller 21 relative to its initial position in real time, and the displacement corresponds to the card thickness;

[0045] Data processing module 6: Receives signals from displacement detection unit 5 and outputs card thickness data through a pre-calibrated displacement-thickness relationship model;

[0046] Among them, the elastic support module 3 and the roller detection module 2 work together to make the roller 21 contact the card surface and be lifted when the card passes through. The elastic support module 3 and the shock absorption module 4 work together to limit the jumping height of the roller 21, so that the roller 21 resets in ≤0.1 seconds after a single card passes through.

[0047] The elastic element 31 (such as a compression spring) releases its stored potential energy after the card passes through, pushing the roller 21 to quickly reset. Combined with the damping effect of the shock absorption module 4 (such as a hydraulic damper), an underdamped system is formed, allowing the roller 21 to complete vibration damping within 0.1 seconds, avoiding overshoot. Through parameter matching (the ratio of stiffness k to damping coefficient c), the system approaches the critical damping state (damping ratio ζ≈1), achieving a balance between rapid response and overshoot suppression, ensuring that the displacement detection unit 5 obtains a stable signal.

[0048] The shock absorption module 4 effectively filters out high-frequency vibrations (>10Hz), preventing the displacement sensor from generating noise signals due to mechanical vibration, and reducing the standard deviation of thickness detection to within ±0.005mm. The elastic support provides constant contact pressure (e.g., 2-5N), ensuring that the roller 21 maintains stable contact with the card surface and avoiding thickness measurement deviations caused by pressure fluctuations.

[0049] When the card has creases or foreign objects, the elastic support absorbs the instantaneous impact force (>50N), and in conjunction with the energy dissipation mechanism of the shock absorption module 4, it prevents the roller 21 assembly from being damaged by hard collision.

[0050] The composite support structure (spring + damping) makes the system insensitive to conveyor belt vibration (amplitude ≤0.3mm) and maintains a stable measurement benchmark when the equipment operating speed changes (0.5-2m / s).

[0051] See Figure 1 The roller detection module 2 includes multiple rollers 21 arranged in parallel along the direction of the conveyor belt, with a spacing of 10~50mm between each roller 21, covering the entire surface area of ​​the card.

[0052] Spatial sampling optimization: The 10-50mm spacing design balances detection density and cost, ensuring coverage of 5-15 sampling points for standard cards (such as ID-1 cards 85.6×54mm), conforming to ISO / IEC 7810 size specifications. Through full-surface contact, localized deformations such as edge warping (typical value ≤0.3mm) can be detected.

[0053] Adjacent rollers 21 form a rolling contact wave, ensuring that at least two rollers 21 are in contact simultaneously during card movement (speed 0.5-2m / s), avoiding detection blind spots and improving the spatial resolution of thickness data to 1mm / sampling point.

[0054] Multi-point collaborative measurement employs Kalman filtering to perform spatiotemporal fusion of displacement data from multiple rollers 21, effectively suppressing noise caused by conveyor belt vibration (amplitude ≤0.3mm), reducing the standard deviation of thickness measurement from ±0.008mm for a single roller 21 to ±0.003mm. By comparing the differences in readings of adjacent rollers 21, local bulges (≥0.1mm) or dents in the card can be identified, triggering a graded early warning mechanism.

[0055] Dynamic reference correction: The first roller 21 detects the leading edge of the card, triggering a reference surface update algorithm to compensate for the dynamic offset of the conveyor belt (lateral ±1mm, longitudinal ±0.5mm), ensuring that the thickness measurement system error is ≤0.02mm. A gradient spacing design (dense at the front and sparse at the rear) combined with a variable-speed sampling strategy maintains an effective sampling rate of ≥50Hz within a speed range of 0.5-2m / s, meeting the requirements of high-speed detection.

[0056] Any three adjacent rollers 21 constitute a detection unit. When a single roller 21 fails, the detection accuracy is maintained by neighborhood interpolation, which complies with the IEC 62058 reliability standard.

[0057] Multiple rollers 21 share the impact load of the card (peak force ≤ 80N), reducing the force on a single roller 21 to below 20N, thus extending the life of the elastic element 31 (expected life ≥ 100 million cycles).

[0058] Among them, the elastic support module 3 is at least one of compression spring, disc spring or pneumatic elastomer, and its stiffness coefficient is 300~1000N / m.

[0059] By matching the stiffness coefficient (k=ΔF / Δx), a preload of 2-5N is provided at the initial position to ensure stable contact between roller 21 and the card surface. When the card thickness changes by 0.1mm, the contact force fluctuation is ≤±1N, avoiding scratches on the card surface. The progressive stiffness characteristic of the disc spring (stiffness increases with compression) automatically compensates for displacement fluctuations (±0.3mm) caused by conveyor belt vibration, keeping the contact force stable within a safe threshold (5-20N).

[0060] With a stiffness of 300 N / m, a 0.1 mm change in card thickness corresponds to a 0.03 N change in force. Combined with a high-sensitivity displacement sensor (resolution ≤ 1 μm), a thickness detection resolution of 0.005 mm can be achieved.

[0061] The stiffness coefficient and the mass of roller 21 (typically 50g) form a second-order system with a natural frequency fn=√(k / m) / 2π≈8-15Hz, avoiding the dominant frequency of conveyor belt vibration (usually <8Hz) and suppressing resonance interference.

[0062] Pneumatic elastomers achieve nonlinear stiffness by compressing gas (such as nitrogen). In the event of a sudden impact (such as a collision with the edge of a card), the instantaneous stiffness can be reduced to 100 N / m, absorbing more than 80% of the impact energy and protecting the measurement system.

[0063] The disc spring combination design generates geometric nonlinear deformation under overload (>50N), limiting the maximum displacement of roller 21 (≤5mm) and preventing damage to the displacement sensor pin.

[0064] Among them, the damping module 4 is at least one of hydraulic damper, magnetorheological damper or viscous damper, with a damping coefficient of 30~100 N·s / m.

[0065] When the damping coefficient c = 30~100 N·s / m, it forms an overdamped system with the elastic support module 3 (k = 500 N / m) (damping ratio ζ = c / (2√(km)) ≈ 0.8~2.5), making the vibration decay time of roller 21 ≤ 0.08 seconds, which shortens the reset time by 20% compared with the critical damping state (ζ = 1), and meets the 0.1-second reset index.

[0066] The vibration frequency of the conveyor belt (≤8Hz) is reduced by 40dB / dec, which suppresses the output noise of the displacement detection unit 5 and improves the signal-to-noise ratio of thickness measurement by 12dB.

[0067] When the card passes through (Δt=0.05 seconds), the damper dissipates 85% of the impact kinetic energy, limiting the overshoot of roller 21 to ≤0.2mm, thus preventing the displacement sensor striker from triggering the protection threshold.

[0068] By compensating for the phase lead of the elastic element 31 through the damping hysteresis characteristic, the phase margin of the system is ≥45°, ensuring that the real-time error of the thickness data is ≤5ms.

[0069] Temperature robustness: The viscous damper uses silicon-based damping fluid (viscosity index VI≥150), and the damping coefficient fluctuates by ≤±8% in the range of -20~60℃, which is more environmentally stable than hydraulic dampers (fluctuation ±15%).

[0070] Impact load adaptation: When an abnormal impact (>50N) is detected, the magnetorheological damper increases the damping coefficient to 500N·s / m instantaneously through electromagnetic adjustment, thereby increasing the absorption of impact energy by 3 times.

[0071] The displacement detection unit 5 is at least one of a laser displacement sensor, a capacitive displacement sensor, or a magnetic grating ruler, with a resolution ≤0.01mm.

[0072] The laser sensor forms a 0.1mm spot using a Class 1 laser beam (wavelength 650nm), which generates diffuse reflection on the surface of roller 21. The CMOS sensor array resolves the displacement with a linearity error ≤0.03%, achieving ultra-precision measurement with a resolution of 0.001mm.

[0073] The capacitive sensor establishes a function of electrode spacing-capacitance (C=εS / d), adopts a shielded electrode design, and achieves a resolution of 0.005mm within a range of 0-5mm, making it particularly suitable for surface detection of metal rollers 21.

[0074] The magnetic scale reads the magnetic pole changes of the magnetic scale through the recording head. It adopts a 20μm grid pitch design and, together with sine / cosine dual-channel signal interpolation, achieves absolute position measurement with a resolution of 0.002mm.

[0075] High-frequency sampling capability: Configured with a sampling rate of ≥10kHz, it fully captures the displacement waveform of the roller 21 when the card passes through (Δt=0.05 seconds), ensuring that thickness feature points are not lost.

[0076] Digital filtering algorithm: An adaptive FIR filter (cutoff frequency fc=500Hz) is used to filter out conveyor belt vibration noise (typical value ±0.02mm), so that the effective signal-to-noise ratio is ≥60dB.

[0077] See Figure 1 The guide component of the conveyor belt module 1 includes adjustable limit baffles 7 on both sides, the baffle spacing is adapted to the card width ±1mm, and the surface friction coefficient of the conveyor belt is ≥0.6.

[0078] The baffle spacing is set based on the standard card width (e.g., 54mm for ID-1 cards), and the ±1mm adjustment range is compatible with card manufacturing tolerances (ISO / IEC 7810 specifies a width tolerance of ±0.15mm) and warping deformation (typical value ≤0.3mm), ensuring that more than 95% of cards maintain a centerline offset of ≤0.5mm during transmission.

[0079] The edges of the baffle are covered with an elastic material (such as polyurethane), which produces an elastic deformation of 0.2-0.5mm when in contact with the card, thus limiting lateral displacement and preventing rigid collision damage to the card edges.

[0080] See Figure 3 The surface of roller 21 is covered with an elastic material layer 22, with a Shore hardness of 20A~60A and a thickness of 1~5mm.

[0081] Pressure homogenization: According to Hertz contact theory, when the soft elastic layer (E≈1~10MPa) comes into contact with the card, the contact radius expands by 3-5 times, reducing the maximum contact stress to σ_max=F / (πa²)≤5MPa (assuming load F=5N), thus avoiding scratching the card surface (ISO / IEC 10373 requires scratch depth ≤0.01mm).

[0082] When the transmission acceleration is 5 m / s², the elastic layer dissipates the impact energy through the viscoelastic effect (loss factor η≈0.1-0.3), reducing the peak pressure fluctuation amplitude from ±30% when there is no elastic layer to ±8%.

[0083] Thickness tolerance compensation: For cards with a thickness fluctuation of ±0.2mm, a 5mm thick elastic layer can produce a compression deformation of 0.3-0.8mm. With the help of the displacement detection unit 5, thickness measurement compensation is achieved, reducing the system error from ±0.05mm to ±0.015mm.

[0084] The 20A low-hardness material can produce local deformation (Δy / Δx≈0.5), which can accommodate the arc-shaped deformation of the card (maximum 0.8mm) and keep the contact surface in effective contact of more than 90%.

[0085] Among them, the data processing module 6 integrates an anomaly detection algorithm, which triggers a stop signal when the detection interval between two consecutive cards is less than 0.1 seconds or the thickness mutation value is greater than 50% of the nominal value.

[0086] Anti-overlap detection: When the detection interval Δt < 0.1 seconds (corresponding to a linear speed v > 8.5 m / s or card spacing < 85 mm), a timing anomaly judgment is triggered. This threshold is set based on the standard card length (ID-1 card 85.6 mm) and the maximum design speed of the conveyor belt (10 m / s), with a 10% safety margin reserved to effectively prevent thickness misjudgment caused by two cards overlapping and entering the detection area.

[0087] Under rated capacity (e.g., 120 sheets / minute), the theoretical interval Δt = 0.5 seconds. The 0.1-second threshold can detect speed loss or card feeding mechanism failure in advance, avoiding batch errors.

[0088] Multi-card stacking detection: The thickness change threshold is set to 50% (e.g., nominal 0.76mm → change to >1.14mm), which can identify abnormalities such as double card stacking (theoretical thickness 1.52mm) or card adhesion (adhesive thickness >0.38mm). Combined with the compression monitoring of the elastic roller 21 (Δd>2mm), dual verification is achieved.

[0089] The exponentially weighted moving average (EWMA) algorithm is used to assign different weights to the thickness data of the first 10 cards (the latest data has a weight of 0.6) to establish a dynamic baseline, so that the thickness mutation judgment can adapt to the fluctuations of production batches (such as normal fluctuations of ±0.05mm).

[0090] When a change in temperature and humidity is detected (ΔT>5℃ or ΔRH>20%), the thickness abrupt change threshold is automatically relaxed to 60% to compensate for the thermal expansion and contraction effect of the material (typical expansion coefficient 50×10⁻). 6 / ℃).

[0091] Correlation analysis was performed between abnormal time intervals and thickness abrupt events to construct a fault tree model. For example: Δt < 0.1 seconds + thickness abrupt change > 50% → 90% probability of feeding mechanism jamming; Δt normal + thickness abrupt change → 45% probability of laminator failure. When abnormal time intervals are triggered three consecutive times, the conveyor belt tension detection program (strain gauge monitoring ΔL / L ≤ 0.5%) is activated to predict belt wear or motor step loss.

[0092] Example 1 (Infrastructure Implementation)

[0093] Device structure:

[0094] Conveyor Module 1:

[0095] The conveyor belt body 11 is made of polyurethane synchronous belt (2mm thick, surface friction coefficient 0.65), driven by servo motor (200W power), with a speed adjustment range of 0.5~5m / s;

[0096] The guide assembly consists of adjustable aluminum alloy baffles on both sides, with a spacing adapted to the width of a bank card (85.6mm ± 0.5mm).

[0097] Roller detection module 2:

[0098] Three floating rollers 21 (30mm in diameter, 20mm apart) are arranged along the direction of the conveyor belt, and their surfaces are covered with a conductive silicone layer (Shore hardness 40A, thickness 2mm).

[0099] Roller 21 is connected to elastic support module 3 via a vertical guide rod (8mm in diameter).

[0100] Elastic support module 3 and shock absorption module 4:

[0101] The elastic support module 3 is a compression spring (wire diameter 2mm, stiffness k=600N / m), with a preload of 12N;

[0102] The shock absorption module 4 is a parallel hydraulic damper (damping coefficient c=60N·s / m), which limits the maximum runout height of the roller 21 to ≤0.08mm;

[0103] Displacement detection unit 5:

[0104] A Keyence IL-300 laser displacement sensor (resolution 0.001mm) is used, which is vertically mounted directly above the roller 21, with a sampling rate of 10kHz;

[0105] Data Processing Module 6:

[0106] Built-in displacement-thickness relationship model, through formula

[0107] h(t) = \frac{F(t) - c \frac{dh(t)}{dt}}{k} Real-time thickness calculation;

[0108] in:

[0109] F(t) is the externally applied force (unit: Newton, N).

[0110] kk is the spring stiffness coefficient (unit: Newton / meter, N / m).

[0111] h(t) is the displacement (unit: meters, m);

[0112] cc is the damping coefficient (unit: Newton-second / meter, N·s / m);

[0113] dh(t)dtdtdh(t) is the velocity (unit: meters per second, m / s).

[0114] Anomaly detection algorithm settings: An alarm is triggered when the interval between consecutive cards is less than 0.1 seconds or the thickness changes by more than 50%.

[0115] Work results:

[0116] When the card passes through at a speed of 3m / s, the reset time of roller 21 is ≤0.05 seconds, and the thickness detection error is ±0.015mm;

[0117] Dynamic calibration result of standard thickness block (0.76mm): CPK≥1.67.

[0118] Example 2 (Extended Implementation with Multiple Rollers 21)

[0119] Structural improvements:

[0120] Roller detection module 2:

[0121] Five rollers 21 (spaced 15mm apart) are arranged along the conveyor belt to cover the entire surface of the card;

[0122] The surface of roller 21 is coated with a polyurethane elastic layer (Shore hardness 50A, thickness 3mm) to enhance wear resistance.

[0123] Elastic support module 3:

[0124] A disc spring (stiffness k=800N / m) is connected in series with a magnetorheological damper (damping coefficient c=80N·s / m);

[0125] The magnetorheological damper adjusts the damping force by adjusting the current to adapt to different card speeds (1~5m / s).

[0126] Dynamic calibration unit:

[0127] Displacement data of standard thickness blocks of 0.5mm, 1.0mm, and 1.2mm are pre-stored to correct model parameters in real time;

[0128] After calibration, the dynamic error was reduced to ±0.01mm.

[0129] Technical advantages:

[0130] Multi-scroller 21 layout enables generation of card thickness distribution cloud map (see) Figure 1 );

[0131] The active adjustment capability of magnetorheological dampers improves stability under high-speed conditions.

[0132] Example 3 (Low-Cost Implementation)

[0133] Structural simplification:

[0134] Elastic support module 3:

[0135] A pneumatic elastomer (stiffness k=400N / m) is used, and the preload force (8~15N) is adjusted by air pressure.

[0136] Shock Absorption Module 4:

[0137] Using a viscous damper (damping coefficient c=40N·s / m) reduces costs by 30%;

[0138] Displacement detection unit 5:

[0139] Replace it with a capacitive displacement sensor (resolution 0.005mm), which is installed on the side of roller 21;

[0140] Data Processing Module 6:

[0141] The algorithm is simplified by using linear interpolation to replace the solution of differential equations, making it suitable for industrial control computers with low computing power.

[0142] Applicable scenarios:

[0143] Low-speed detection scenarios (≤1m / s), such as ID card initial inspection production lines;

[0144] The thickness detection error is ±0.03mm, and the cost is reduced by 50% compared to Example 1.

[0145] Example 4 (Anti-interference Implementation)

[0146] Anti-interference design:

[0147] Guided component optimization:

[0148] A polytetrafluoroethylene (PTFE) sliding strip (friction coefficient 0.1) is added to the inside of the conveyor belt baffle to reduce card offset resistance;

[0149] Roller 21 material improvement:

[0150] The surface is coated with carbon fiber reinforced rubber (Shore hardness 60A, thickness 1mm) to reduce high-speed friction temperature rise;

[0151] Enhanced data processing:

[0152] An integrated wavelet transform algorithm is used to separate the conveyor belt vibration noise (frequency > 100Hz) from the displacement signal of roller 21.

[0153] The thickness mutation threshold has been adjusted to 30% to reduce the false alarm rate.

[0154] In the description of this utility model, it should be understood that the terms "middle", "length", "upper", "lower", "front", "rear", "vertical", "horizontal", "inner", "outer", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0155] In this invention, unless otherwise expressly specified and limited, the first feature "on" the second feature may be in direct contact with the first feature, or indirect contact with the first feature through an intermediate medium. "A plurality of" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

[0156] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0157] The above description is merely illustrative of the embodiments of this utility model and is not intended to limit the scope of this utility model. For those skilled in the art, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model without creative labor should be included within the protection scope of this utility model.

Claims

1. A card thickness detection device, comprising a frame, characterized in that, include: Conveyor belt module: Used for continuous card transport, located at the bottom of the frame, including the conveyor belt body and drive mechanism; Roller detection module: Located above the conveyor belt, it includes at least one roller; Elastic support module: Connected above the roller detection module, it includes elastic elements to provide elastic restoring force when the roller is compressed; Vibration damping module: Located between the elastic support module and the roller detection module, it is used to suppress the vertical vibration of the roller; Displacement detection unit: electrically connected to the roller detection module, it measures the vertical displacement of the roller relative to its initial position in real time, and the displacement corresponds to the card thickness; Data processing module: Receives signals from the displacement detection unit and outputs card thickness data through a pre-calibrated displacement-thickness relationship model; The elastic support module works in conjunction with the roller detection module to make the roller contact the card surface and be lifted up when the card passes through. The elastic support module works in conjunction with the shock absorption module to limit the roller's jumping height, so that the roller's reset time after a single card passes through is ≤0.1 seconds.

2. The card thickness detection device according to claim 1, characterized in that: The roller detection module includes multiple rollers arranged in parallel along the direction of the conveyor belt, with a spacing of 10~50mm between each roller, covering the entire surface area of ​​the card.

3. The card thickness detection device according to claim 1, characterized in that: The elastic support module is at least one of a compression spring, a disc spring, or a pneumatic elastomer, with a stiffness coefficient of 300~1000 N / m.

4. The card thickness detection device according to claim 1, characterized in that: The damping module is at least one of a hydraulic damper, a magnetorheological damper, or a viscous damper, with a damping coefficient of 30~100 N·s / m.

5. The card thickness detection device according to claim 1, characterized in that: The displacement detection unit is at least one of a laser displacement sensor, a capacitive displacement sensor, or a magnetic grating ruler, with a resolution ≤0.01mm.

6. The card thickness detection device according to claim 1, characterized in that: The conveyor belt module is equipped with adjustable limit baffles on both sides, with the baffle spacing adapted to the card width ±1mm, and the surface friction coefficient of the conveyor belt ≥0.

6.

7. The card thickness detection device according to claim 1, characterized in that: The roller surface is covered with an elastic material layer with a Shore hardness of 20A~60A and a thickness of 1~5mm.

8. The card thickness detection device according to claim 1, characterized in that: The data processing module integrates an anomaly detection algorithm. When the detection interval between two consecutive cards is less than 0.1 seconds or the thickness mutation value is greater than 50% of the nominal value, a stop signal is triggered.

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