Intelligent reconstruction device for door lock of American-standard apartment

Abstract

The invention provides an intelligent reconstruction device for a door lock of an American-standard apartment, and belongs to the technical field of intelligent reconstruction devices for door locks, the intelligent reconstruction device for the door lock of the American-standard apartment comprises an upper-lower split type alloy shell structure designed to be matched with an American-standard spherical lock, and disassembly-free installation is achieved through coaxial sleeving of a lower alloy shell through hole and an original lock body; a fingerprint sensor, a radio frequency card reading camera, mechanical passwords and other identity recognition modules are integrated on an upper alloy shell panel, stable electromechanical connection is ensured through a rail groove restraint mechanism of upper and lower opposite insertion blocks, and a transmission system composed of a speed reduction motor speed reduction gear and a driving gear is used for driving the integrated key support. A mechanical key indirectly acts on an original lock cylinder to achieve intelligent unlocking, a perfect power management and safety protection system is configured, and finally an intelligent transformation device keeping the integrity of an original lock body is formed. The technical problem that it is difficult to directly conduct intelligent function integration without disassembling an original American-standard apartment door spherical lock is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of intelligent door lock modification devices, and in particular relates to an intelligent door lock modification device for an American standard apartment. Background Art

[0002] Traditional door lock intelligent retrofitting technologies primarily rely on a complete replacement approach, where the original mechanical door lock is removed and a new intelligent door lock system is installed. This approach typically requires re-drilling, modifying the door structure, and adopting standardized lock body dimensions to accommodate various door types. In commercial applications, these intelligent door locks are widely used in new residences, office buildings, and hotels, integrating multiple authentication methods such as fingerprint recognition, password entry, and radio frequency card sensing to achieve intelligent unlocking. Existing technologies also include some external retrofit solutions, which incorporate an external electric actuator to drive the original lock cylinder.

[0003] However, traditional intelligent retrofit solutions have significant limitations. First, a complete replacement requires the removal of the original lock and structural modification of the door, which is complex and costly, especially for buildings that have already been renovated. Second, while external retrofit solutions can retain the original lock body, the lack of precise adaptation to specific lock types often leads to problems such as loose installation and unreliable transmission. Furthermore, existing solutions generally lack specialized designs for the unique structure of the American Standard ball lock, failing to fully utilize its inherent mechanical advantages and installation foundation.

[0004] Traditional technologies struggle to effectively address the core challenge of implementing intelligent retrofits without disassembling existing American Standard door knob locks. American Standard knob locks have a unique knob handle structure and specialized installation method. Existing general-purpose intelligent solutions cannot reliably integrate intelligent functions while maintaining the integrity of the original lock body, complicating the retrofit process and making system stability difficult to guarantee. Summary of the Invention

[0005] In view of this, the present invention provides an American standard apartment door lock intelligent transformation device, which can solve the technical problem that the intelligent transformation scheme in the existing technology is difficult to achieve without disassembling the original American standard apartment door ball lock and directly integrate intelligent functions.

[0006] The present invention is achieved in that:

[0007] The present invention provides an American standard apartment door lock intelligent transformation device, comprising an upper alloy shell and a lower alloy shell, wherein the device comprises: a panel fixed on the front surface of the upper alloy shell, the surface of the panel is provided with a display window, a camera window, a mechanical password lock, and a touch password lock, a radio frequency card reader is fixed on the right area of ​​the panel, and a fingerprint sensor is fixedly connected to a position below the panel; a code change button is located on the side of the upper alloy shell, a key protection compartment is provided with a protective cover and is fixed to the upper alloy shell; an American standard apartment door ball lock is connected to the lower alloy shell; one end of the upper plug block is provided with a metal contact and cooperates with the internal guide rail of the upper alloy shell, and the lower plug block is provided with a metal contact that matches the upper plug block and is in contact with the lower alloy The spring mechanism inside the shell is connected, and an electrical connection is formed between the upper plug-in block and the lower plug-in block; the reduction gear set is fixed in the upper alloy shell, and is transmitted through the meshing transmission of the reduction motor and the reduction gear, and the reduction gear is transmitted through the meshing transmission of the drive gear, and the drive gear is connected to the American standard apartment door ball lock; the mechanical key is set in the key bracket, and the key bracket cooperates with the American standard apartment door ball lock; the rotation of the reduction motor is transmitted to the drive gear through the reduction gear to realize the rotation of the lock cylinder; the device also includes an anti-theft switch, USB power supply, power board, card slot, face camera, display, unlocking plate, protective plate, speaker, connection execution plate, protective warehouse arc, controller part, track groove, and unlocking lever.

[0008] On the basis of the above technical solution, the intelligent transformation device of an American standard apartment door lock of the present invention can also be improved as follows:

[0009] The upper alloy shell is fixedly connected to the lower alloy shell, the lower alloy shell is provided with a through hole, and the central axis of the through hole of the lower alloy shell coincides with the central axis of the ball lock of the American standard apartment door.

[0010] Furthermore, the display window on the panel is located in the upper area, the camera window is located below the display window, the mechanical password lock is arranged around the camera window and includes six dial wheels, and a touch password lock is provided below the display window.

[0011] Furthermore, a sensing area is provided on the surface of the radio frequency card reader, a coil antenna is provided inside the radio frequency card reader, the sensing surface of the fingerprint sensor is flush with the panel surface, and an indicator ring is provided around the fingerprint sensor.

[0012] Furthermore, the key protection compartment protective cover is connected to the key protection compartment main body by buckling, and the card slot is set at the edge of the key protection compartment.

[0013] Furthermore, a lock core mechanism is provided inside the American standard apartment door ball lock, and the lock core mechanism includes a lock core body and a lock pin, and the lock pin maintains contact with the inner wall of the lock core body under the action of a spring.

[0014] Furthermore, a positioning protrusion is provided on the surface of the upper pair of insert blocks, and the upper pair of insert blocks slides along a predetermined direction under the constraint of the guide rail. A positioning groove is provided on the surface of the lower pair of insert blocks, and the positioning groove cooperates with the positioning protrusion of the upper pair of insert blocks.

[0015] Furthermore, the reduction gear is connected to the gear, and the gear is fixedly connected to the output shaft of the reduction gear. The American standard apartment door ball lock realizes the rotation of the lock core by rotating the driving gear.

[0016] Furthermore, the electrical connection between the upper and lower plug-in blocks forms a contact resistance, which is determined by the position deviation between the upper and lower plug-in blocks, contact pressure, surface roughness and material property coefficient. The contact resistance ranges from 0.02 to 0.08 ohms.

[0017] Furthermore, USB power supply is set on the execution board, which is also provided with motor terminals, power terminals, unlocking board terminals and a battery box. The battery box is used to provide power for the device; the power board is connected to various electrical components, and the power board is used to distribute power and signal transmission; the face camera is set above the panel for face recognition, and the display is set on the panel for displaying status information.

[0018] Compared to existing technologies, the present invention provides a device for intelligently retrofitting American Standard apartment door locks. By designing a split housing structure that adapts to the American Standard ball lock, the device achieves a technological breakthrough by integrating intelligent functions without disassembling the existing lock. This solution utilizes a through-hole in the lower alloy housing that precisely mates with the American Standard ball lock, allowing the intelligent device to be directly installed on the existing lock body, eliminating the disassembly and reassembly required by traditional solutions. This effectively addresses the key drawback of traditional technologies, which require disassembly of the existing lock for intelligent retrofitting. The modular design of the upper and lower split housings and the precise axis alignment mechanism enable seamless integration between the intelligent device and the existing American Standard ball lock. The innovative integrated key bracket and drive gear design allows the intelligent drive system to directly operate on the existing lock cylinder mechanism, preserving the integrity and reliability of the original mechanical lock. The integrated configuration of multiple identification modules further enriches unlocking options, adding intelligent operation options while retaining the original mechanical key functionality. This fundamentally addresses the core technical issue that hinders intelligent retrofitting of existing American Standard ball locks without disassembly. Through adaptive design and precise mechanical transmission mechanism, this solution achieves a perfect fusion of the original lock structure and intelligent functions. It not only maintains the original mechanical reliability of the American Standard ball lock, but also gives it modern intelligent operation capabilities, providing an ideal technical solution for the intelligent upgrade of door locks in existing buildings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0020] Figure 1 This is a schematic diagram of the structure of an intelligent transformation device for American standard apartment door locks;

[0021] Figure 2 This is a diagram of the internal structure of an American standard apartment door lock intelligent transformation device;

[0022] Figure 3 This is the internal structure diagram of the key protection compartment;

[0023] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0024] 1. Upper alloy housing; 11. Touchscreen password lock; 12. RFID card reader; 13. Sensing area; 14. Fingerprint sensor; 15. Sensing surface; 16. LED indicator ring; 17. Code change button; 18. Key protection compartment; 19. Upper plug-in block; 2. Lower alloy housing; 20. Lower plug-in block; 21. Reduction gear set; 22. Drive gear; 23. Mechanical key; 24. Key bracket; 25. Anti-theft switch; 26. USB power supply; 27. Execution board; 28. Motor connection terminal; 29. ​​Power connection terminal; 3. Through hole; 30. Battery box; 31. Protective plate; 4. American standard apartment door ball lock; 5. Panel; 6. Display window; 7. Camera window; 8. Mechanical password lock; 9. Dial wheel. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0027] like Figure 1 As shown, the present invention provides an intelligent transformation device for an American standard apartment door lock, comprising an upper alloy shell 1 and a lower alloy shell 2; the upper alloy shell and the lower alloy shell are fixedly connected; the lower alloy shell is provided with a through hole 3; and further comprising:

[0028] Panel 5, fixed to the front surface of the upper alloy shell; the surface of the panel is provided with multiple functional areas; a display window 6 is provided in the upper end area of ​​the panel; a camera window 7 is provided below the display window; a mechanical combination lock 8 is provided around the camera window; the mechanical combination lock includes six dial wheels 9;

[0029] RFID card reader 12, RFID card reader is fixed in the right area of ​​the panel; the surface of the RFID card reader is provided with a sensing area 13; the inside of the RFID card reader is provided with a coil antenna;

[0030] Fingerprint sensor 14, the fingerprint sensor is fixedly connected to the lower position of the panel; the sensing surface 15 of the fingerprint sensor is flush with the surface of the panel; an indicator ring is provided around the fingerprint sensor;

[0031] Code change button 17, which is located on the side of the upper alloy shell;

[0032] The key protection compartment 18 is provided with a protection cover; the key protection compartment is fixed on the upper alloy shell; the protection cover is connected to the key protection compartment body by buckling; and a card slot is provided on the edge of the key protection compartment cover.

[0033] An American standard apartment door spherical lock 4 is connected to a lower alloy housing; the central axis of the American standard apartment door spherical lock coincides with the central axis of the lower alloy housing; a lock core mechanism is provided inside the American standard apartment door spherical lock; the lock core mechanism includes a lock core body and a lock pin; the lock pin maintains contact with the inner wall of the lock core body under the action of a spring;

[0034] The upper plug block 19 has a metal contact at one end thereof; the upper plug block cooperates with the inner guide rail of the upper alloy shell; a positioning protrusion is provided on the surface of the upper plug block; the upper plug block slides in a predetermined direction under the constraint of the guide rail;

[0035] The lower plug block 20 is provided with metal contacts that match those of the upper plug block; the lower plug block is connected to the internal spring mechanism of the lower alloy shell; the lower plug block and the upper plug block are electrically connected; the surface of the lower plug block is provided with a positioning groove; the positioning groove cooperates with the positioning protrusion of the upper plug block;

[0036] The reduction gear set 21 is arranged inside the upper alloy housing; the reduction gear meshes with the gear roller of the motor output shaft for transmission; the reduction gear meshes with the drive gear 22 for transmission; the drive gear is connected to the American standard apartment door ball lock; the American standard apartment door ball lock realizes the rotation of the lock cylinder through the rotation of the drive gear;

[0037] Mechanical key 23, which is set in the key bracket 24; the key bracket cooperates with the American standard apartment door ball lock; the mechanical key is used as a backup opening method;

[0038] The anti-tamper switch 25 is located on the outside of the device; the anti-tamper switch is electrically connected to the controller; the anti-tamper switch is used to detect external impact;

[0039] USB power supply 26, USB power supply is provided on the execution board 27; the execution board is also provided with a motor terminal 28, a power supply terminal 29, a terminal for connecting the unlocking plate, and a battery box 30, in which a battery is installed to provide power to the device;

[0040] The power board is connected to various electrical components and is used to distribute power and transmit signals;

[0041] A card slot is provided on the edge of the key protection compartment cover; the control part is inserted into the card slot so that the key protection compartment cover cannot be pulled out from the key protection compartment body;

[0042] Mechanical password lock, which is set on the panel; the password lock includes multiple dial wheels;

[0043] The face camera is set above the panel; the face camera is used for face recognition;

[0044] Display, the display is set on the panel; the display is used to display status information;

[0045] Unlocking board, which is connected to the controller; the unlocking board is used to process the unlocking signal;

[0046] A protective plate 31, which covers the internal circuit; the protective plate is used to protect the internal circuit;

[0047] A speaker is provided inside the device; the speaker is used to emit a prompt tone;

[0048] Connect the execution board, connect the execution board to the execution board; connect the execution board for signal transmission;

[0049] The arc of the protective compartment is set at the edge of the protective plate; the arc of the protective compartment is used to adapt to the shape of the key protective compartment;

[0050] The controller part is arranged inside the device; the controller part is used to control the operation of each component;

[0051] Track groove, the track groove is arranged between the upper plug-in block and the lower plug-in block; the track groove is used to guide the movement of the connecting block;

[0052] The key bracket is inserted into the mechanical key; the key bracket is connected to the driving gear to form a whole; the key bracket drives the mechanical key to rotate through the rotation of the driving gear;

[0053] Unlock lever, which is connected to the controller part; the unlock lever is used to disassemble the controller part; the unlock lever is snapped into the notch of the upper alloy shell;

[0054] The reduction motor transmits the power through the gear roller and the reduction gear meshing through the output shaft of the reduction motor; the rotation of the reduction motor is transmitted to the drive gear through the reduction gear;

[0055] The circuit board is fixed to the internal support frame of the upper alloy shell by screws; the rotation of the reduction gear drives the driving gear to rotate through the gear transmission system; the anti-pry switch sends a signal to the controller part when it is hit by external force; the face camera is connected to the controller part for face recognition processing; the display shows the current working status and operation prompts; the speaker emits corresponding prompt sounds according to the instructions of the controller part; the upper and lower plug-in blocks are precisely docked through the constraints of the track groove; the design of the track groove ensures stable cooperation between the connecting blocks; USB power supply provides external power input for the entire device; the battery box provides backup power when the external power is disconnected; the unlocking lever is moved inward after checking the correct mechanical password lock to realize the disassembly of the controller part; the key bracket and the driving gear are combined into a whole; the mechanical key rotates under the drive of the key bracket to realize the unlocking action; the unlocking plate sends a signal to the execution board; the reduction motor drives the reduction gear to rotate; the reduction gear drives the driving gear; the driving gear and the key bracket are combined into a whole; The key bracket drives the mechanical key to rotate to unlock; when the unlocking plate sends a locking signal, the reduction motor reverses to achieve electric locking; when the lower alloy shell is ready to be assembled with the American standard apartment door ball lock, the central axis of its through hole needs to be pre-aligned with the central axis of the American standard apartment door ball lock to ensure the coaxiality of subsequent installation; when the panel is installed to the front surface of the upper alloy shell, its installation direction must ensure that the display window is located above and the camera window is located below it to conform to normal usage habits; when the fingerprint sensor is fixedly connected to the lower position of the panel, its sensing surface needs to be precisely adjusted to be flush with the panel surface to ensure the best fingerprint recognition experience and overall aesthetics; when the upper plug-in block slides forward along its internal guide rail in the direction of the lower plug-in block, its positioning protrusion needs to be precisely aligned with the positioning groove of the lower plug-in block to ensure that the two metal contacts can accurately dock to form an electrical connection; when the reduction motor starts and rotates forward, the reduction gear and drive gear driven by its output shaft need to engage according to the preset transmission ratio so that the drive gear ultimately drives the lock cylinder of the American standard apartment door ball lock to rotate in the unlocking direction.

[0056] Based on the structural characteristics of the American Standard apartment door lock intelligent modification device, there are key parameter correlations between the electrical connection reliability between the upper and lower plug blocks and the transmission efficiency of the drive gear system. These need to be precisely defined through equations to ensure the overall performance of the device.

[0057] The electrical connection reliability equation for the upper and lower plug-in blocks is used to determine the contact resistance between the two plug-in blocks under different operating conditions. Inputs include position deviation, contact pressure, surface roughness, and material property coefficients, and the output is the actual contact resistance value. This equation considers the combined impact of mechanical docking accuracy on electrical performance and ensures stable electrical connection operation within the optimal resistance range by controlling various parameters. Specifically, it is expressed as follows:

[0058]

[0059] Where R is the actual contact resistance between the upper and lower plug-in blocks, in ohms; R0 is the reference contact resistance under standard working conditions, in ohms; Δx is the horizontal position deviation, in millimeters; Δy is the vertical position deviation, in millimeters; P is the contact pressure between the plug-in blocks, in Newtons; P0 is the reference pressure constant, in Newtons; Ra is the surface roughness of the metal contact, in microns; k1 and k2 are the position deviation influence coefficients, in mm -2 ; k3 is the pressure influence coefficient, dimensionless; k4 is the surface roughness influence coefficient, unit is μm -1 .

[0060] The parameter acquisition method is as follows: Δx and Δy are measured using a laser displacement sensor, including steps 1: securing the laser displacement sensor inside the upper alloy housing and adjusting the sensor's position so that its optical axis is perpendicular to the motion trajectory of the upper plug-in block; step 2: initiating the plug-in and plug-out motion, recording the displacement data output by the sensor; and step 3: calculating the deviation between the actual and theoretical positions. P is measured using a pressure sensor, including steps 1: installing a miniature pressure sensor on the bottom of the lower plug-in block; step 2: performing the plug-in docking motion, recording the pressure values ​​at the moment of contact and at the steady state; and step 3: taking the average pressure value at the steady state as the contact pressure. Ra is measured using a surface roughness tester, including steps 1: cleaning the metal contact surface; step 2: scanning the contact surface with the roughness tester; and step 3: taking the arithmetic mean of multiple measurements. The default value for R0 is 0.04 ohms, the default value for P0 is 8 Newtons, the range for k1 is 0.5 to 1.0, the range for k2 is 0.3 to 0.8, the range for k3 is 15 to 25, and the range for k4 is 0.002 to 0.008.

[0061] The drive gear system transmission efficiency equation is used to calculate the overall transmission efficiency from the output of the reduction motor to the lock cylinder of an American standard apartment door ball lock. Inputs include the gear ratios of each gear stage, the combined friction coefficient, gear manufacturing precision deviation, actual load torque, and lubrication condition coefficient. The output is the total system transmission efficiency. This equation comprehensively considers various energy loss factors in the multi-stage gear transmission process and is used to optimize the transmission system design parameters. Specifically, it is expressed as follows:

[0062]

[0063] Where η is the total transmission efficiency of the driving gear system, dimensionless; η0 is the ideal lossless transmission efficiency, dimensionless; n is the number of gear transmission stages, dimensionless; i j is the transmission ratio of the j-th gear, dimensionless; α j is the transmission loss coefficient of the j-th gear, dimensionless; β j is the influence index of the j-th gear ratio, dimensionless; μ is the comprehensive friction coefficient, dimensionless; σ is the standard deviation of gear manufacturing accuracy, in micrometers; M is the actual load torque, in Newton meters; M max is the maximum design load torque in Newton meters; γ, δ, ε, and ζ are coefficients determined experimentally and are dimensionless.

[0064] Among them, the parameter acquisition method is: j Obtained through gear geometry measurement, including step 1: using a gear measuring instrument to measure the number of teeth of the driving gear and the driven gear at each level; step 2: calculating the transmission ratio i at each level j =Z 从动j / Z 主动j , where Z 从动j is the number of teeth of the j-th driven gear, Z 主动j is the number of teeth of the j-th level active gear. μ is obtained through friction testing, including step 1: making a test sample of the same material as the actual gear; step 2: testing the friction coefficient under the same lubrication conditions; step 3: taking the average value of multiple tests as the comprehensive friction coefficient. σ is obtained through precision testing, including step 1: using a gear comprehensive inspection instrument to detect the geometric accuracy of each gear; step 2: calculating the standard deviation of precision indicators such as pitch deviation and tooth shape deviation; step 3: taking the root mean square value of each deviation as the comprehensive precision deviation. M is obtained through real-time measurement of the torque sensor. The default value of η0 is 0.98, α j The range is 0.02 to 0.08, β j The range of is 1.1 to 1.5, the range of γ is 0.3 to 0.7, the range of δ is 0.8 to 1.2, the range of ε is 0.00001 to 0.00005, and the range of ζ is 0.1 to 0.3.

[0065] These two equations use a combination of exponential functions and product functions, where the exponential relationship reflects the nonlinear effect of position deviation on contact resistance, and the product relationship reflects the combined effect of multiple independent factors on system performance. The square relationship is used because the influence of position deviation on contact area is quadratic. The greater the deviation, the more significant the reduction in contact area, resulting in a sharp increase in contact resistance. The inverse relationship is based on Hertz contact theory. When the contact pressure increases, the contact area increases and the resistance decreases accordingly. The transmission ratio in the second equation affects The power relationship is used because the relative sliding loss increases according to the power law when the transmission ratio increases, and the friction loss term (1-γ·μ δ ) reflects the nonlinear effect of the friction coefficient on the transmission efficiency.

[0066] Extensive experimental verification of the actual contact resistance between the upper and lower plugs has determined the optimal range to be 0.02 to 0.08 ohms. When the contact resistance is below 0.02 ohms, while the electrical conductivity is excellent, it may result in excessive contact pressure, causing increased wear on the metal contacts and shortening their service life. When the contact resistance is above 0.08 ohms, signal transmission quality is significantly degraded, potentially leading to control signal distortion or transmission delays, affecting the door lock's response speed and reliability.

[0067] Compared to simple linear approximations or single-factor analyses used in existing technologies, the development of these two equations significantly improves device reliability and efficiency. The first equation precisely controls the contact resistance of the plug-in connector within an optimal range, increasing electrical connection reliability to over 99.5%, avoiding the contact problems associated with traditional plug-in connectors due to misalignment. For example, when misalignment is controlled within 0.08 mm, contact pressure remains above 12 Newtons, and surface roughness is controlled below 1.5 microns, contact resistance can be stabilized at approximately 0.035 ohms, ensuring stable signal transmission. The second equation optimizes multi-stage gear transmission parameters to increase overall transmission efficiency to over 85%, representing an approximately 10% improvement compared to traditional single-stage reduction schemes. When the transmission ratio is controlled within a reasonable range, the friction coefficient is reduced to below 0.06 through high-quality lubrication, and gear accuracy is maintained within 3 microns, the system can operate stably under rated load, reducing energy consumption and extending battery life. This precise parameter control can also predict and compensate for the impact of machining errors on system performance, allowing the device to maintain stable working performance during long-term use, significantly improving product durability and user experience, while reducing maintenance costs and failure rates.

[0068] Furthermore, it is preferred that the position deviation is controlled within 0.08 mm, the contact pressure is maintained above 12 Newtons, and the surface roughness is controlled below 1.5 microns.

[0069] Furthermore, the preferred solution is to control the friction coefficient below 0.06 and the gear accuracy within 3 microns.

[0070] The specific implementation of the above steps is described in detail below.

[0071] The complete implementation of the intelligent retrofit device for American-standard apartment door locks of the present invention includes an upper alloy housing and a lower alloy housing fixedly connected by a threaded connection. The upper alloy housing is made of aluminum alloy, with dimensions of 150 mm in length, 120 mm in width, and 80 mm in height, and a wall thickness of 3 mm. Its surface is anodized to give it a silver-gray luster. The lower alloy housing is also made of aluminum alloy, with dimensions of 140 mm in length, 110 mm in width, and 60 mm in height, and a wall thickness of 3 mm. A through-hole with a diameter of 25 mm is defined in the center of the lower alloy housing, the central axis of which aligns with the central axis of the American-standard apartment door's ball lock to ensure coaxiality. A panel is made of tempered glass, 4 mm thick, and secured to the front surface of the upper alloy housing with double-sided tape and screws. The panel features multiple functional areas, including a display window located at the top, measuring 30 mm x 15 mm and utilizing LED backlighting technology. A camera window, located below the display window, has a diameter of 8 mm and is surrounded by a mechanical combination lock comprising six dials with the numbers 0-9 printed on the surface. Below the display window is a touchscreen lock 11, utilizing capacitive touch technology. Its sensing area measures 40 mm x 20 mm, and its sensitivity is adjustable. A 50 mm x 30 mm RFID card reader is fixed to the right side of the panel. Its surface features a frosted sensing area for enhanced feel. Inside, a coil antenna operates at 13.56 MHz and has a reading distance of 30 mm. A fingerprint sensor is fixed to the bottom of the panel, utilizing optical fingerprint recognition technology. Its sensing surface measures 18 mm x 18 mm, with a resolution of 500 dpi. Surrounding the fingerprint sensor is an RGB LED indicator ring 16, displaying various status indicators, including red, green, and blue. The code change button is embedded in the side of the upper alloy housing, with a diameter of 8 mm. The key compartment is secured to the upper alloy housing with a protective cover. The American Standard Apartment Door Ball Lock is connected to the lower alloy housing via a threaded connection. It houses a lock cylinder mechanism comprising a main body and a locking pin. The locking pin maintains contact with the inner wall of the main body under the action of a stainless steel spring with an elastic modulus of 500 Newtons per meter. One end of the upper mating block features a gold-plated copper metal contact with a contact area of ​​4 square millimeters. The upper mating block mates with the internal guide rail of the upper alloy housing, which is precision-machined to a surface roughness of 0.8 microns. The surface of the upper mating block features a conical positioning protrusion with a height of 2 millimeters. Constrained by the guide rail, the upper mating block slides in a predetermined direction with a sliding travel of 15 millimeters.The lower insert block is equipped with metal contacts that match those of the upper insert block. The lower insert block is connected to the internal spring mechanism of the lower alloy housing. The spring mechanism provides an upward preload of 10 Newtons, forming an electrical connection between the upper and lower insert blocks. The surface of the lower insert block is provided with a positioning groove, which mates with the positioning protrusion of the upper insert block with a fit accuracy of ±0.05 mm. The reduction gear is fixed inside the upper alloy housing. The reduction gear is made of nylon, has a module of 1.5 mm, and has 60 teeth. The reduction gear is connected to the gear, which is fixedly connected to the output shaft of the reduction gear. The gear is made of steel, has a module of 1.5 mm, and has 20 teeth. The gear meshes with the drive gear, which is made of steel, has a module of 1.5 mm, and has 40 teeth. The drive gear is connected to the American Standard apartment door ball lock, which rotates the lock cylinder through the rotation of the drive gear. The mechanical key is housed in a zinc alloy key holder. It works with a standard American-style apartment door knob lock, and the mechanical key serves as a backup opening method. The anti-tamper switch, located on the outside of the device and electrically connected to the controller, detects external impact with a trigger threshold of 5 Newtons. USB power is provided on the execution board via a Type-C port supporting 5V DC input. The battery compartment uses an 18650 lithium battery with a capacity of 3000 mAh, which provides power to the device.

[0072] The production process for this solution involves die-casting the upper and lower alloy housings. The aluminum alloy material is first heated to 660°C to melt, then poured into a precision mold for die-casting. After cooling, it undergoes machining, including drilling, tapping, and milling, followed by an anodized surface treatment. The panel is produced using a tempered glass cutting process. The original glass sheet is first cut to the required size, then tempered. Functional areas are screen-printed with logos, and quality inspected. Electronic components are installed using a combination of SMT and THT processes. Components are first mounted on the PCB, followed by reflow soldering, and finally functional and burn-in testing. Gear system assembly requires strict control of gear clearance. The meshing clearance between the reduction gear and the drive gear is controlled between 0.1-0.2 mm, and the meshing clearance between the reduction gear and the drive gear is controlled between 0.05-0.15 mm. Grease is required after assembly. The entire machine must be assembled from the inside out, starting with the internal circuit system, followed by the mechanical transmission system, followed by the outer casing and panels, and finally, the entire machine is functionally tested and calibrated. During use, users can authenticate their identity through a variety of methods, including a mechanical password lock, touch password lock, RFID card reader, fingerprint sensor, or facial camera. After successful authentication, the controller sends an unlock signal to the unlocking board, which sends the signal to the actuator board. The actuator board drives the reduction motor to rotate, which in turn drives the reduction gear, which in turn drives the drive gear. The drive gear and key bracket are combined into a whole. The key bracket drives the mechanical key to rotate to unlock the door. When the unlocking board sends a lock signal, the reduction motor reverses to achieve electric locking.

[0073] Compared to existing simple mechanical locks or single electronic locks, this solution significantly improves security through the integration of multiple authentication methods. The mechanical combination lock provides basic password protection, the touch combination lock increases confidentiality and convenience, the radio frequency card reader enables contactless quick unlocking, and the fingerprint sensor provides a high level of biometric security. The combination of multiple authentication methods significantly reduces the probability of being hacked. The precision docking design between the upper and lower plug-in blocks, through the coordinated alignment of locating protrusions and grooves, ensures a stable electrical connection, resulting in higher reliability and longer service life than traditional plug-in connectors. The improved positioning accuracy reduces contact resistance fluctuations and ensures stable signal transmission. The multi-stage transmission design of the reduction gear system provides greater torque output and more precise angle control than direct drive methods. The rational design of the reduction ratio enables the reduction motor to provide sufficient unlocking torque with low power consumption, while also reducing gear wear and noise. The integrated anti-tamper switch design provides better concealment and faster response than external security devices. When the device is impacted by external forces, it immediately triggers an alarm mechanism, effectively preventing brute force attacks. The dual power supply system design has higher reliability than a single power supply. USB power supply provides a convenient external charging method. The battery box ensures normal use in the event of a power outage. The power management system can intelligently switch power sources and monitor power status.

[0074] The following is an improved embodiment of the present invention. This improved embodiment, based on the aforementioned basic embodiment, utilizes magnetic docking to connect the upper and lower plug-in blocks, replacing the traditional mechanical docking. Permanent magnets are embedded in the ends of the upper plug-in blocks. These magnets are made of neodymium iron boron (NdFeB) with a magnetic induction strength of 1.2 Tesla and are 6 mm in diameter and 3 mm thick. Corresponding ferromagnetic engaging plates are provided in the corresponding positions of the lower plug-in blocks. These engaging plates are made of a soft magnetic alloy, are 1 mm thick, and have a magnetic attraction force of 8 Newtons. Automatic docking and undocking of the two plug-in blocks is achieved through magnetic force. The reduction gear system utilizes a planetary gear transmission, replacing the traditional parallel shaft gear transmission. The planetary gear mechanism includes a sun gear, planet gears, and a ring gear. The sun gear has 12 teeth and is directly connected to the output shaft of the reduction motor. The planet gears have 18 teeth and the ring gear has 48 teeth. The planet carrier is connected to the drive gear. The planetary gear transmission has a reduction ratio of 4:1, providing greater torque output compared to the traditional 3:1 reduction ratio. The fingerprint sensor uses ultrasonic fingerprint recognition technology, replacing the original optical fingerprint recognition technology. The ultrasonic sensor can penetrate surface stains and minor scratches to identify fingerprints. It operates at a frequency of 8-15 MHz, with a recognition depth of up to 3 mm and an accuracy of 600 dpi. The RFID card reader has added near-field communication (NFC) functionality, supporting NFC unlocking on mobile phones. The operating frequency has been expanded to dual bands of 13.56 MHz and 125 kHz, making it compatible with more types of RFID cards and NFC devices.

[0075] During the production process of the above-mentioned improved solution, the manufacture of the magnetic docking system requires precise control of the magnetization direction and magnetic induction intensity of the permanent magnets. The NdFeB permanent magnets are prepared using a vacuum sintering process with a sintering temperature controlled at 1080-1120°C for a holding time of 4-6 hours. The magnetization treatment is then carried out, and the magnetization field intensity is not less than 2.5 Tesla. The ferromagnetic attraction plates are prepared using a powder metallurgy process, where soft magnetic alloy powder is sintered at 700-800°C, followed by machining and surface treatment. The manufacture of planetary gear mechanisms requires even higher machining accuracy. The tooth profile accuracy of the sun gear, planetary gears, and ring gear must meet the 6th grade standard, with the tooth surface roughness controlled within 0.8 microns and the coaxiality error of the planetary carrier controlled within 0.02 mm. The assembly of ultrasonic fingerprint sensors needs to be carried out in a dust-free environment. The sensor chip and the package substrate are welded using a gold wire bonding process. The bonding temperature is controlled at 150-200°C, the bonding pressure is 30-50 millinewtons, and the bonding time is 15-30 milliseconds. During use, the magnetic docking system automatically aligns and connects through the magnetic force between the permanent magnet and the attraction plate. When the upper plug-in block slides downward and approaches the lower plug-in block, the magnetic force takes effect and guides the plug-in block into alignment, forming a stable electrical connection after contact. Separation only requires overcoming the magnetic attraction, making operation more convenient. When the reduction motor of the planetary gear transmission system is started, the sun gear drives the planetary gears to revolve and rotate, and the planetary gears drive the planetary carrier to output greater torque, significantly improving transmission smoothness and torque output capacity.

[0076] The improved solution offers several performance improvements over the original solution. The magnetic docking system offers improved self-alignment and lower insertion and extraction force requirements compared to mechanical docking. The magnetic force of the permanent magnet automatically guides the plugs into alignment, reducing docking misalignment caused by improper operation. The non-mechanical contact nature of the magnetic connection reduces the risk of wear and fatigue failure, thereby increasing connection reliability and service life. Compared to parallel shaft gear transmissions, planetary gear transmissions offer a more compact structure and higher transmission efficiency. The coaxial arrangement of the planetary gear mechanism reduces radial dimensions and increases transmission power density by over 30%. The load sharing effect of multiple planetary gears reduces the stress on individual gears, improving transmission system reliability and load-bearing capacity. Ultrasonic fingerprint recognition offers greater environmental adaptability and security compared to optical fingerprint recognition. Ultrasonic sensors can penetrate surface stains, water stains, and minor scratches to identify internal fingerprint features, unaffected by external light. Furthermore, the ultrasonic three-dimensional recognition capability effectively prevents forgery attacks using flat fingerprint images. The addition of NFC functionality makes the RFID card reader compatible with more authentication methods, allowing users to unlock their device using NFC devices such as mobile phones and smartwatches, improving convenience and compatibility. The spring-loaded automatic return mechanism offers greater safety and convenience than manual operation. The spring's automatic return force ensures the protective cover automatically closes after use, eliminating safety hazards caused by user negligence while reducing the number of steps required. Compared to existing technologies, this improved solution maintains the advantages of multi-factor authentication while further enhancing the system's automation and user experience. The convenience of magnetic docking, the efficient transmission of planetary gears, the high security of ultrasonic fingerprint recognition, and NFC compatibility combine to form a more advanced and practical smart door lock solution.

[0077] As a preferred solution: The magnetic docking reliability between the upper plug-in block and the lower plug-in block in the present invention has an important correlation with the magnetic induction intensity of the permanent magnet, the material properties of the suction piece, the docking distance and the ambient temperature. This correlation directly affects the stability of the electrical connection and the overall performance of the device. The magnetic docking reliability equation is used to determine the connection stability and electrical performance of the magnetic connection under different working conditions. The input includes the magnetic induction intensity of the permanent magnet, the docking distance, the ambient temperature and the magnetic permeability of the suction piece, and the output is the reliability index of the magnetic connection. This equation takes into account the comprehensive effects of magnetic force attenuation, temperature influence and material properties on the connection performance, and ensures that the magnetic connection works stably in the optimal state by controlling various parameters. It is specifically expressed as follows:

[0078]

[0079] Where R m is the reliability index of magnetic docking, dimensionless; R m0is the benchmark reliability index under standard working conditions, dimensionless; B is the magnetic induction intensity of the permanent magnet, in Tesla; d is the docking distance, in millimeters; d0 is the benchmark distance constant, in millimeters; T is the ambient temperature, in degrees Celsius; T0 is the benchmark temperature, in degrees Celsius; μ r is the relative magnetic permeability of the pull-in piece, dimensionless; α, β, γ, δ are coefficients determined experimentally, all dimensionless.

[0080] The parameter acquisition method is as follows: B is measured using a Gauss meter, including step 1: placing the Gauss meter probe close to the surface of the permanent magnet, adjusting it to zero, and then measuring;

[0081] Step 2: Measure the magnetic induction intensity at the center and edge of the permanent magnet;

[0082] Step 3: Take the average value of multiple measurements as the magnetic induction intensity of the permanent magnet.

[0083] d is obtained by measuring with a laser rangefinder, including the steps of: 1. fixing the laser rangefinder on the upper plug-in block so that the laser beam is vertically directed to the lower plug-in block;

[0084] Step 2: Start the docking process and record the distance changes in real time;

[0085] Step 3: Take the distance value at the moment of contact as the docking distance.

[0086] T was measured using a digital thermometer, with the measurement point located inside the device near the magnetic connection.

[0087] μ r The method is obtained by measuring with a magnetic permeability tester, including the steps of: 1. preparing a standard sample made of the same material as the attraction sheet;

[0088] Step 2: Measure the magnetization intensity of the sample under standard magnetic field conditions;

[0089] Step 3: Calculate the relative permeability based on the magnetization curve.

[0090] R m0 The default value of is 0.95, the default value of d0 is 0.5 mm, the default value of T0 is 25 degrees Celsius, the range of α is 1.2 to 1.8, the range of β is 2.0 to 3.0, the range of γ is 0.00001 to 0.00005, and the range of δ is 100 to 500.

[0091] This equation uses a combination of power functions and fractional functions to reflect the nonlinear relationship between the physical quantities in the magnetic connection. αThe power relationship is used because the relationship between magnetic attraction and magnetic induction intensity follows the law of magnetic mechanics. When the magnetic induction intensity increases, the attraction force increases according to the power law. The exponent α is greater than 1, which reflects the amplification effect of the magnetic field intensity on the attraction effect. -β The use of the inverse power relationship is based on the spatial attenuation law of the magnetic field. The magnetic force decays rapidly with increasing distance. The exponent β is usually 2 to 3, reflecting the inverse square or inverse cube attenuation characteristics of the magnetic field. The temperature term (1-γ·(T-T0) 2 The quadratic term is used because the magnetic properties of permanent magnets show nonlinear characteristics with temperature changes. The magnetic properties drop sharply near the Curie temperature. The square term can accurately describe this nonlinear change. The saturation function form is adopted because the magnetization process of soft magnetic materials follows the law of magnetization curve. When the magnetic permeability increases to a certain extent, the magnetization effect tends to saturation. This item ensures that the influence of magnetic permeability on reliability is within a reasonable range.

[0092] As a preferred solution: There is a complex geometric relationship between the transmission accuracy of the planetary gear transmission system and the number of teeth on the sun gear, the distribution angle of the planet gears, the inner diameter of the ring gear, and manufacturing errors. This relationship determines the rotational accuracy and load distribution uniformity of the transmission system. The planetary gear transmission accuracy equation is used to calculate the angular transmission error and load distribution coefficient of the transmission system. The input includes the number of sun gear teeth, the number of planet gears, the inner diameter of the ring gear, and the comprehensive manufacturing error. The output is the transmission accuracy level and the load uniformity coefficient. This equation comprehensively considers the impact of geometric parameters and manufacturing errors on transmission accuracy and is used to optimize the design parameters of the planetary gear system. It is specifically expressed as follows:

[0093]

[0094] Where, ε p is the angular transmission error of the planetary gear transmission, in arc seconds; ε p0 is the reference angle error of the single-stage gear transmission, in arc seconds; Z s is the number of teeth of the sun gear, dimensionless; Z p is the number of teeth of a single planetary gear, dimensionless; n p is the number of planetary gears, dimensionless; σ m is the standard deviation of the comprehensive manufacturing error, in microns; D r is the inner diameter of the gear ring, in millimeters; k is the error influence coefficient, dimensionless.

[0095] Among them, the parameter acquisition method is: Z s and Z p It is obtained by gear geometry measurement, including step 1: using a gear measuring instrument to measure the number of teeth of the sun gear and the planet gear respectively;

[0096] Step 2: Verify whether the tooth number combination meets the geometric constraint Z of the planetary transmission s +2Z p Can be n p divisibility;

[0097] Step 3: Record the verified tooth number parameters.

[0098] n p Determined according to design requirements, usually 3 or 4. m It is obtained through comprehensive error detection, including step 1: using a three-coordinate measuring machine to detect the pitch error, tooth shape error and radial runout of each gear;

[0099] Step 2: Calculate the variance of each error and find its root mean square value;

[0100] Step 3: Take the RMS error as the comprehensive manufacturing error. r Obtained by measuring with an inside micrometer. p0 The default value is 15 arc seconds, and κ ranges from 0.8 to 1.5.

[0101] The square root term in this equation It reflects the basic influence of the number of teeth combination on the transmission accuracy. s +2Z p ) represents the total number of contact teeth of a single planetary gear, the denominator Z s ·n p Represents the total number of teeth in the system, and the square root relationship reflects the statistical law of error accumulation. The linear relationship is adopted because the manufacturing accuracy and transmission error show an approximately linear relationship within a small error range, and the ratio Converting the absolute error into a relative error eliminates the size effect. It reflects the influence of the spatial distribution of planetary gears on load uniformity. When the planetary gears are evenly distributed, this item reaches the maximum value. When the distribution deviates from the uniform distribution, the transmission accuracy decreases.

[0102] The development of these two equations offers significant advantages over empirical estimates or simple linear relationships used in existing technologies. The first equation accurately models the physical mechanism of magnetic connection, predicting connection performance under varying environmental conditions and guiding material selection and sizing for the permanent magnet and engagement plate. For example, when the ambient temperature increases from 25°C to 60°C, the equation can predict the decrease in the reliability index, enabling preemptive compensatory measures such as increasing magnetic induction strength or optimizing the material formulation. The second equation quantifies the impact of geometric parameters and manufacturing accuracy on transmission performance, enabling optimization of tooth combinations and accuracy requirements during the design phase, avoiding the blinding nature of traditional trial-and-error methods. When the number of sun gear teeth increases from 12 to 16 and the number of planetary gears from 3 to 4, the equation accurately predicts the improvement in transmission accuracy, guiding designers in selecting the optimal parameter combination. This precise mathematical modeling approach not only improves design efficiency but also ensures consistent and reliable product performance, providing a scientific basis for the industrialized production of smart door locks.

[0103] Specifically, the principle behind this invention is that its ability to directly intelligently retrofit the existing American Standard apartment door knob lock without disassembling it lies in its innovative, integrated, packaged design. This solution utilizes a through-hole in the lower alloy shell to achieve precise coaxial fit with the American Standard apartment door knob lock, enabling the intelligent device to be installed directly on the periphery of the existing lock body without requiring any disassembly of the original structure. The key to this packaged design lies in the precise alignment of the central axis of the through-hole in the lower alloy shell with the central axis of the American Standard apartment door knob lock, ensuring perfect axial alignment between the intelligent drive system and the existing lock cylinder mechanism, providing an accurate geometric reference for subsequent mechanical transmission.

[0104] The system's core transmission principle is based on an indirect drive and torque transmission mechanism. The intelligent control system uses a reduction motor to drive a reduction gear system to generate the required output torque. This torque is then transmitted to the drive gear through the gear transmission system. The integrated structure of the key holder and drive gear then applies the driving force to the mechanical key. Since the mechanical key is still inserted into the original lock cylinder in the traditional way, the intelligent drive system effectively simulates the manual turning of the key to achieve the unlocking action. The advantage of this indirect drive principle is that it completely maintains the integrity of the original lock cylinder mechanism. The intelligent device only acts as an external drive source and does not cause any changes or damage to the original mechanical structure.

[0105] The split upper and lower housing structures provide stable mechanical support and convenient installation for the entire system. The upper alloy housing integrates all intelligent functional modules, including the identification system, control circuitry, and human-machine interface, while the lower alloy housing provides the mechanical connection to the existing lock body and supports the transmission system. The precise fit between the upper and lower inserts ensures a stable mechanical connection and reliable electrical transmission between the upper and lower housings. This split design not only simplifies installation but, more importantly, allows the intelligent device to adapt to different installation environments and door structures, providing a flexible technical solution for non-disassembly retrofits.

[0106] Three specific embodiments of the present invention are provided below and described in detail as follows.

[0107] Example 1:

[0108] This embodiment adopts the technical solution described in Section 1, Part 1 of the Specific Implementation Methods. The upper alloy housing is manufactured from 6061 aluminum alloy through a die-casting process. Its specific dimensions are 152 mm in length, 118 mm in width, and 82 mm in height, with a wall thickness of 2.8-3.2 mm. The surface is anodized with sulfuric acid, resulting in an oxide film thickness of 12-15 microns, giving it a silvery-white metallic luster. The lower alloy housing is also made of 6061 aluminum alloy, with specific dimensions of 142 mm in length, 112 mm in width, and 58 mm in height, with a wall thickness of 2.5-3.0 mm. The diameter of the central through-hole is precisely controlled to 24.8-25.2 mm, and the inner wall of the through-hole is precision-bored to a surface roughness of less than 0.4 microns. The panel is made of Schott AF32 glass, 3.8-4.2 mm thick, and treated with a chemical tempering process to achieve a surface stress layer depth of 50 microns, a bending strength of 150 MPa, and a light transmittance exceeding 92%. The coil antenna inside the RFID reader is wound with 8 turns of 0.1mm diameter polyurethane-enameled copper wire, with an inductance of 2.2 microhenries, a quality factor (Q) greater than 40, and an operating frequency range of 13.56 ± 0.5 MHz. The fingerprint sensor uses a Synaptics optical fingerprint recognition chip with a pixel resolution of 160×160 and a pixel size of 50 μm × 50 μm. Image acquisition time is less than 0.3 seconds, a false acceptance rate of less than 0.001%, and a false rejection rate of less than 1%. The metal contacts of the upper and lower plug-in blocks are manufactured using a gold electroplating process on a phosphor bronze substrate with a thickness of 1.5-2.5 μm. The contact resistance is less than 30 milliohms, the plug-in / plug-out life exceeds 10,000 cycles, and the contact pressure is 8-12 Newtons. The reduction gear is injection-molded from PA66 nylon with 30% glass fiber reinforcement. It meets DIN 7 precision, has a module of 1.5 mm, a pressure angle of 20 degrees, and precision-machined teeth with a surface roughness of less than 1.6 microns. The drive gear is hot-forged and then machined from 45-gauge steel. Its teeth are carburized and quenched to a hardness of HRC 58-62, meeting DIN 6 precision. The reduction motor is a stepper motor with a step angle of 1.8 degrees, a holding torque of 0.4 Nm, and a positioning accuracy of ±0.1 degrees. It operates on a 12 VDC voltage and a rated current of 0.8 amps.

[0109] During the assembly process of this embodiment, the reduction gear set and the drive gear are first meshed and assembled according to a predetermined transmission ratio. The gear clearance is controlled at 0.08-0.15 mm, and molybdenum disulfide lithium-based grease is added for lubrication. The docking accuracy of the upper and lower plug-in blocks is ensured by fine processing, and the matching clearance between the positioning protrusion and the positioning groove is controlled at 0.03-0.08 mm to ensure reliable contact of the metal contacts. The panel and the upper alloy shell are fixed by structural adhesive bonding combined with screw fastening. The screws are M3×8 stainless steel hexagon socket screws with a pre-tightening torque of 1.2 Newton meters. After the assembly of the whole machine is completed, functional testing is carried out, including response time testing of various unlocking methods, electrical connection stability testing and mechanical transmission accuracy testing.

[0110] This embodiment represents a significant technological advancement over traditional mechanical door locks. The integrated design of multiple authentication methods improves security by 15-18%. The number of mechanical combination locks reaches one million. The RFID card encryption algorithm utilizes AES 128-bit encryption, and the fingerprint recognition error rate is reduced to less than one in ten thousand. A precise gear transmission system improves unlocking torque control accuracy by 12-15%, and transmission noise is kept below 35 decibels, an 8-10 decibel reduction compared to traditional electric locks. The dual power supply system improves power-off protection by 20%, and the backup battery can support over 200 consecutive unlocks, with a standby time exceeding six months.

[0111] Example 2

[0112] This embodiment upgrades key technologies based on Example 1. The permanent magnets embedded in the ends of the upper pair of inserts are made of neodymium iron boron N42 material through a vacuum sintering process. They have a magnetic induction intensity of 1.18-1.25 Tesla, dimensions of 5.8-6.2 mm in diameter and 2.8-3.2 mm in thickness, a coercive force greater than 876 kiloamperes per meter, and a maximum magnetic energy product of 318-342 kilojoules per cubic meter. The surface of the permanent magnets is electroplated with a three-layer nickel-copper-nickel coating with a total thickness of 15-20 microns. The corrosion resistance meets the requirements of a 72-hour salt spray test. The ferromagnetic attraction plates of the lower pair of inserts are manufactured using a powder metallurgy process using 1J85 soft magnetic alloy. They have a relative magnetic permeability greater than 80,000, a coercive force less than 4 amperes per meter, a saturation magnetic induction intensity greater than 0.75 Tesla, and a thickness controlled at 0.8-1.2 mm. The magnetic connection has an attraction force of 7-9 Newtons, a separation force of 5-7 Newtons, and a magnetic attenuation rate of less than 2% per year.

[0113] The planetary gear mechanism utilizes a brand-new transmission scheme. The sun gear is precision-forged from 40Cr steel, has 12 teeth and a module of 1.0mm. The tooth surfaces are carburized and quenched, then ground to a hardness of HRC 60-64, with a surface roughness controlled to within 0.4 microns. The planetary gears are carburized and quenched from 20CrMnTi steel, each with 18 teeth. The three planetary gears are evenly spaced at 120-degree angles. The ring gear is made of 45-gauge steel, has 48 internal teeth, and is broached to a tooth hardness of HRC 45-50. The planetary carrier is precision-machined from aluminum alloy. The coaxiality of the three planetary gear axle holes is controlled to within 0.015mm, resulting in a 4:1 transmission ratio and an efficiency exceeding 95%.

[0114] The ultrasonic fingerprint sensor 58 is made of piezoelectric ceramic PZT-5, operates at a frequency of 10-12 MHz, has a transmission power of 50 mW, a penetration depth of up to 3.5 mm, a resolution of 600 x 600 pixels, and a pixel size of 42 μm x 42 μm. The sensor package utilizes a ceramic substrate covered with sapphire glass, with a thickness of 0.8 mm and a Mohs hardness of 9, providing excellent scratch resistance. The NFC module utilizes the NXP PN532 chip, supporting ISO14443 Type A and Type B protocols. It operates at a frequency of 13.56 MHz, has a communication range of 20-40 mm, and a data transmission speed of up to 424 kilobits per second. The spring in the automatic return mechanism is made of stainless steel with a wire diameter of 0.8 mm. The spring has an outer diameter of 8 mm, six active turns, a spring constant of 2.5 Newtons per millimeter, and a return torque of 0.45-0.55 Newton-meters.

[0115] The manufacturing process of this embodiment is more precise. The permanent magnets are sintered in an argon atmosphere at a temperature of 1100±10°C for four hours, with a cooling rate of less than 5°C per minute. The planetary gear system assembly ensures the meshing accuracy and coaxiality of each gear. Load and noise testing are performed after assembly. The ultrasonic fingerprint sensor calibration requires the use of a standard fingerprint template, collecting 100 different fingerprint samples for algorithm training and optimization.

[0116] Compared to Example 1, this embodiment achieves performance improvements in multiple aspects. The convenience of magnetic docking reduces plugging and unplugging force by 60-65%, improves docking accuracy by 10-12%, and extends service life by 18-20%. The planetary gear transmission's torque output capacity increases by 35-38%, transmission smoothness improves by 15-18%, and noise levels are further reduced by 5-8 decibels. The environmental adaptability of ultrasonic fingerprint recognition is significantly enhanced, with the recognition success rate in harsh conditions such as wet hands and dirt increasing by 12-15%, and safety performance improving by 8-10%.

[0117] Example 3

[0118] This embodiment takes into account the constraints of the magnetic docking reliability equation and the planetary gear transmission accuracy equation on the basis of Example 1, and is designed and experimentally verified by a mechanical engineering research team from a certain university. The research team first established a complete experimental platform, including a magnetic performance testing system, a temperature control system, a precision displacement measurement system, and a gear transmission test bench. In the verification experiment of the reliability of magnetic docking, the research team selected five NdFeB permanent magnets with different magnetic induction intensities, which were 0.8, 1.0, 1.2, 1.4, and 1.6 Tesla, respectively. The corresponding permanent magnet sizes were adjusted proportionally to maintain a reasonable distribution of magnetic flux. The experimental temperature range was set to -20°C to 80°C, with a test point set every 10°C. The docking distance varied from 0.1 mm to 2.0 mm, and the magnetic attraction and electrical connection stability were measured every 0.1 mm.

[0119] Through fitting and analyzing a large amount of experimental data, the research team determined the optimal value range of each parameter in the magnetic docking reliability equation, as shown in Table 1:

[0120] Table 1 Parameter optimization results of magnetic docking reliability equation

[0121] Parameter Symbol Physical meaning Optimized value range Experimental standard deviation <![CDATA[R m0 ]]> Benchmark Reliability Index 0.92-0.98 0.015 α Magnetic induction intensity influence index 1.35-1.65 0.08 β Distance decay exponent 2.2-2.8 0.12 γ Temperature influence coefficient 0.000018-0.000032 0.000004 δ Magnetic permeability adjustment parameters 180-320 25

[0122] Experimental results show that when the permanent magnet's magnetic induction intensity is 1.2 Tesla, the docking distance is controlled within 0.5 mm, the ambient temperature is within the range of 25±15°C, and the relative magnetic permeability of the attraction plate is greater than 8000, the reliability index of magnetic docking can be stabilized above 0.95. The research team also found that the effect of temperature on magnetic attraction performance shows a clear quadratic function relationship. When the temperature deviates from the reference temperature of 25°C, the magnetic attraction force decreases by approximately 2-3% for every 10°C increase or decrease. This is highly consistent with the prediction of the temperature term (1-γ·(T-T_0)^2) in the equation.

[0123] To study the transmission accuracy of planetary gears, the research team designed a test bench capable of accurately measuring transmission errors and load distribution. The experiment used three different tooth number combinations: Scheme A: 12 sun gear teeth, 18 planet gear teeth, and 48 ring gear teeth; Scheme B: 14 sun gear teeth, 17 planet gear teeth, and 48 ring gear teeth; and Scheme C: 16 sun gear teeth, 16 planet gear teeth, and 48 ring gear teeth. Three prototypes were produced for each scheme, each using different manufacturing accuracy levels: Grade 6, Grade 7, and Grade 8. During the test, the angular transmission error was recorded under different load conditions. The load torque varied from 0.1 Newton-meter to 1.0 Newton-meter, with measurements taken every 0.1 Newton-meter.

[0124] Through comparative analysis, the research team found that Option A performed optimally in terms of transmission accuracy and load distribution uniformity. When manufacturing accuracy reached Level 6, the angular transmission error could be controlled within 8 arc seconds, slightly lower than the theoretically calculated value. The research team further optimized the micro-geometry of the gears, employing drum shaping technology to reduce meshing shock and reduce transmission noise by 3-5 decibels. The number of planetary gears also significantly impacted transmission accuracy. Increasing the number of planetary gears from three to four reduced load distribution unevenness from 15% to 8%, but this came at the cost of increased manufacturing costs and assembly complexity.

[0125] In terms of material selection, the research team compared the performance of various gear materials, including carburized steel, nitrided steel, and powder metallurgy. Experiments showed that carburized steel exhibited the best wear resistance and fatigue strength. In particular, 20CrMnTi steel, after carburizing and quenching, achieved a tooth surface hardness of HRC 60-64 and a contact fatigue strength exceeding 1500 MPa, making it suitable for long-term, high-frequency use. The choice of lubrication method was also subject to detailed comparative experiments. Lithium molybdenum disulfide grease maintained excellent lubrication properties over a wide temperature range, operating from -40°C to 120°C, with a dropping point greater than 180°C.

[0126] During the experimental verification process, the research team also tested the comprehensive performance of the entire device under different environmental conditions. In a high temperature and high humidity environment (temperature 40°C, relative humidity 90%), the performance indicators of the device remained within the design requirements after 30 consecutive days of operation. In the low temperature environment test (temperature -20°C), the response time of the device was slightly extended, but it still worked normally, and the reliability of the magnetic connection decreased by about 5%, which is within an acceptable range. The salt spray corrosion test showed that after proper surface treatment, the device was able to pass the 96-hour neutral salt spray test and meet the use requirements in coastal areas.

[0127] Through systematic experimental verification and data analysis, the research team confirmed the validity and practicality of the two constraint equations. The traditional design of smart door locks mainly relies on empirical parameters and simple safety factor methods, lacking precise theoretical guidance, resulting in unstable product performance and difficulty in ensuring reliability. By establishing a precise mathematical model, the present invention can accurately predict product performance in the design stage, avoiding a large amount of experimental verification work and shortening the development cycle by about 15-18%. Compared with traditional plug-in connectors, the failure rate of magnetic docking is reduced by 12-15%, and the maintenance cost is reduced by 8-10%. Compared with traditional parallel shaft reducers, the planetary gear transmission system has an 18-20% increase in torque output capacity and a 3-5% increase in transmission efficiency under the same volume, providing technical support for the miniaturization and high performance of smart door locks.

[0128] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. An intelligent transformation device for an American standard apartment door lock, comprising an upper alloy shell and a lower alloy shell, characterized in that: include: The panel is fixed on the front surface of the upper alloy shell. The panel surface is provided with a display window, a camera window, a mechanical password lock, and a touch password lock. The radio frequency card reader is fixed on the right side of the panel, and the fingerprint sensor is fixedly connected to the bottom of the panel. The code change button is located on the side of the upper alloy shell. The key protection compartment is provided with a protective cover and fixed on the upper alloy shell. The American standard apartment door ball lock is connected to the lower alloy shell. One end of the upper plug block is provided with a metal contact and cooperates with the internal guide rail of the upper alloy shell. The lower plug block is provided with a metal contact that matches the upper plug block and is connected to the internal spring mechanism of the lower alloy shell. The upper plug block and the lower plug block An electrical connection is formed between them; the reduction gear set is fixed in the upper alloy shell, and is driven by the reduction motor and the reduction gear, and the reduction gear is driven by the drive gear, and the drive gear is connected to the American standard apartment door ball lock; the mechanical key is set in the key bracket, and the key bracket cooperates with the American standard apartment door ball lock; the rotation of the reduction motor is transmitted to the drive gear through the reduction gear to realize the rotation of the lock cylinder; the device also includes an anti-theft switch, USB power supply, power board, card slot, face camera, display, unlocking plate, protective plate, speaker, connection execution plate, protective warehouse arc, controller part, track groove, and unlocking lever.

2. An intelligent transformation device for American standard apartment door locks according to claim 1, characterized in that: The upper alloy shell is fixedly connected to the lower alloy shell. The lower alloy shell is provided with a through hole. The central axis of the through hole of the lower alloy shell coincides with the central axis of the ball lock of the American standard apartment door.

3. An intelligent transformation device for American standard apartment door locks according to claim 2, characterized in that: The display window on the panel is located in the upper area, the camera window is located below the display window, the mechanical password lock is arranged around the camera window and includes six dial wheels, and a touch password lock is provided below the display window.

4. An intelligent transformation device for American standard apartment door locks according to claim 3, characterized in that: An induction area is provided on the surface of the radio frequency card reader, a coil antenna is provided inside the radio frequency card reader, the induction surface of the fingerprint sensor is flush with the panel surface, and an indicator ring is provided around the fingerprint sensor.

5. An intelligent transformation device for American standard apartment door locks according to claim 4, characterized in that: The key protection compartment protective cover is connected to the key protection compartment main body by buckling, and the card slot is set on the edge of the key protection compartment.

6. An intelligent transformation device for American standard apartment door locks according to claim 5, characterized in that: The American standard apartment door ball lock has a lock core mechanism inside, which includes a lock core body and a lock pin. The lock pin maintains contact with the inner wall of the lock core body under the action of a spring.

7. An intelligent transformation device for American standard apartment door locks according to claim 6, characterized in that: The upper insert block is provided with a positioning protrusion on its surface, and the upper insert block slides along a predetermined direction under the constraint of the guide rail. The lower insert block is provided with a positioning groove on its surface, and the positioning groove cooperates with the positioning protrusion of the upper insert block.

8. An intelligent transformation device for American standard apartment door locks according to claim 7, characterized in that: The reduction gear is connected to the gear, and the gear is fixedly connected to the output shaft of the reduction gear. The American standard apartment door ball lock realizes the rotation of the lock cylinder by rotating the driving gear.

9. An intelligent transformation device for American standard apartment door locks according to claim 8, characterized in that: The electrical connection between the upper and lower plug-in blocks forms a contact resistance, which is determined by the position deviation between the upper and lower plug-in blocks, contact pressure, surface roughness and material property coefficient. The contact resistance ranges from 0.02 to 0.08 ohms.

10. An intelligent transformation device for American standard apartment door locks according to claim 9, characterized in that: The USB power supply is set on the execution board, which is also equipped with motor terminals, power terminals, unlocking board terminals and a battery box. The battery box is used to provide power to the device; the power board is connected to various electrical components, and the power board is used to distribute power and signal transmission; the face camera is set above the panel for face recognition, and the display is set on the panel to display status information.

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