Double-nut pre-tightening type automatic screw rod assembling device

Abstract

The utility model relates to a double-nut pre-tightening type automatic screw rod assembling device which comprises a base, a nut pre-tightening mechanism and a screw rod driving mechanism. The nut pre-tightening mechanism comprises a fixed assembling table and a slidable movable pushing and pressing assembly. The fixed assembling table is provided with a nut positioning part and a spring adjusting part. The screw rod driving mechanism comprises a polished rod clamp, a sliding bearing seat and a rotary driving device, and the sliding bearing seat is connected with the base through a guide assembly; the movable pushing and pressing assembly comprises a pushing and pressing execution piece and a position locking unit. In the working state, when the pushing and pressing execution piece pushes the second nut to compress the anti-backlash spring and the rotary driving device drives the lead screw to rotate, the sliding bearing base moves along the guide assembly, and automatic screwing connection of the double-nut assembly and the lead screw is achieved. The utility model provides a double-nut pre-tightening type automatic screw rod assembling device which aims at solving the problems that in traditional assembling, pre-tightening force control and screw rod screwing-in actions are difficult to synchronize, assembling efficiency is low, pre-tightening force consistency is poor, and maintenance is inconvenient.

Description

Technical Field

[0001] This utility model relates to the field of mechanical assembly equipment technology, specifically to an automatic assembly device for a double-nut preloaded lead screw. Background Technology

[0002] In the fields of mechanical manufacturing and automated production, lead screw drives, as a common precision transmission method, are widely used in various equipment. The double-nut preloaded lead screw structure can effectively eliminate backlash in lead screw drives, improving transmission accuracy and stability. However, several problems exist in the current assembly process of double-nut preloaded lead screws. Traditional assembly methods mostly rely on manual operation, which is not only inefficient but also makes it difficult to ensure the consistency and accuracy of the preload. Furthermore, the preload control and the screw screw insertion action are difficult to synchronize, easily leading to unstable assembly quality and affecting the performance and service life of the lead screw drive system. In addition, due to the complexity of the assembly process, maintenance of the preload mechanism and drive mechanism is inconvenient, often requiring long downtime and increasing production costs. Therefore, there is an urgent need for a device that can achieve automatic assembly of double-nut preloaded lead screws, improving assembly efficiency and quality, and facilitating maintenance. Utility Model Content

[0003] In view of this, the present invention provides an automatic assembly device for a double-nut preloaded lead screw to solve the problems mentioned in the background art, such as difficulty in synchronizing preload control with lead screw screw insertion, low assembly efficiency, poor preload consistency, and inconvenient maintenance in traditional assembly.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] An automatic assembly device for a double-nut preloaded lead screw includes a base, a nut preload mechanism, and a lead screw drive mechanism. The nut preload mechanism is located on a first side of the base and includes a fixed assembly table and a slidable movable pushing assembly. The fixed assembly table has an axially extending nut positioning part and a spring adjustment part. The lead screw drive mechanism is located on a second side of the base and includes a smooth rod clamp, a sliding bearing seat, and a rotary drive device. The sliding bearing seat is connected to the base through a guide assembly. The movable pushing assembly includes a pushing actuator and a position locking unit. In the working state, when the pushing actuator pushes the second nut to compress the backlash-eliminating spring, and the rotary drive device drives the lead screw to rotate, the sliding bearing seat is displaced along the guide assembly, realizing the automatic screwing connection between the double-nut assembly and the lead screw.

[0006] Through the rigid support of the base and the split-structure design, the functional separation and spatial coordination of the nut preload mechanism and the screw drive mechanism are achieved, solving the problem of difficulty in synchronizing preload control and screw screw insertion in traditional assembly. The nut positioning part and spring adjustment part of the fixed assembly table form an axially connected structure, ensuring the axial alignment accuracy of the first and second nuts and avoiding thread damage caused by misalignment. The sliding characteristics of the movable push assembly, combined with the position locking unit, can precisely control the compression of the backlash-eliminating spring, quickly locking after eliminating the gap between the two nuts to prevent preload rebound. The linkage design of the guide assembly and the sliding bearing seat converts the screw rotation motion into the linear screw insertion motion of the nut assembly, realizing the automation and continuity of the assembly process, significantly improving efficiency and preload consistency compared to manual operation. The overall structure adopts a modular layout, which facilitates the separate disassembly of the preload mechanism or drive mechanism during maintenance, reducing downtime for repairs.

[0007] Preferably, the nut positioning part is a positioning groove for accommodating the first nut, and the spring adjusting part includes a first adjusting groove for accommodating the backlash-free spring and a second adjusting groove for accommodating the second nut. The positioning groove, the first adjusting groove and the second adjusting groove are sequentially connected and coaxially arranged.

[0008] The three-section groove structure connected in an axial series achieves integrated positioning and assembly of the double nuts and backlash-free spring. The positioning groove, precision-machined, ensures the radial positioning accuracy of the first nut, ensuring perfect alignment of its thread axis with the lead screw, eliminating thread engagement deviations caused by manual operation in traditional assembly. The depth of the first adjustment groove matches the free length of the backlash-free spring, providing a visual monitoring window for spring compression stroke while preventing spring mechanical performance degradation due to over-compression. The stepped inner wall structure of the second adjustment groove forms a rotational constraint on the second nut, ensuring that the force transmission direction during preload application is strictly axial. The coaxial design of the three grooves creates a closed force transmission channel, resulting in uniform preload distribution without lateral force interference, significantly improving the assembly coaxiality of the double nut assembly. The modular groove structure supports adaptation to various nut specifications by replacing positioning modules of different sizes, greatly improving equipment versatility. The axial series layout simplifies the assembly process; operators only need to place the components in sequence to complete pre-assembly, significantly reducing preparation time compared to traditional split tooling.

[0009] Preferably, the top surface of the fixed assembly table is provided with a lead screw guide groove that is axially aligned with the positioning groove.

[0010] The lead screw guide groove employs a composite surface structure to achieve self-centering. Its V-shaped surface and flat surface combine to form a dual-reference guide surface, ensuring initial centering accuracy during lead screw insertion. The strict alignment design between the groove axis and the positioning groove fundamentally guarantees precise engagement of the threaded pair, eliminating the risk of misalignment during assembly. The gradually expanding guide section extending to the edge of the assembly table can adaptively correct minute angular deviations at the lead screw end, significantly reducing the difficulty of manual centering. Surface hardening treatment and the application of wear-resistant materials effectively enhance the durability of the guide surface, ensuring dimensional stability during long-term use. The transparent observation window design on the side wall, combined with an optical detection system, allows real-time monitoring of the thread engagement status during lead screw insertion. The separation of the guiding function and load transmission path design allows the insertion thrust to be transmitted through a dedicated load-bearing structure, avoiding bending moment loads on the guide groove, thereby maintaining long-term reliability of guiding accuracy.

[0011] Preferably, the top surface of the fixed assembly table is provided with a guide groove for a smooth rod that is axially aligned with the positioning groove.

[0012] The guide groove for the guide rod employs a multi-roller dynamic guiding mechanism, achieving full circumferential constraint on the guide rod through evenly distributed rolling contact, effectively suppressing radial movement during assembly. The axis of the guiding mechanism remains strictly parallel to the lead screw guiding system, ensuring the coaxiality of the guide rod-lead screw system's motion. The elastic coating on the roller surface provides sufficient guiding stiffness while preventing scratches on the guide rod surface. The end-buffered mechanism absorbs the kinetic energy impact of moving parts, protecting precision components from rigid collision damage. The distributed support design is particularly suitable for assembling slender guide rods, effectively overcoming bending deformation caused by their own weight. The integrated dynamic monitoring system provides real-time feedback on guide rod position deviation and automatically adjusts the guiding pressure, ensuring the accuracy of the motion trajectory during assembly. Compared to traditional fixed guiding methods, the active guiding mechanism significantly improves assembly centering.

[0013] Preferably, the lead screw guide groove and the guide rod guide groove are excavated in the guide block, and the guide block is detachably connected to the fixed assembly table, such as by means of bolts or buckles.

[0014] The modular guide blocks are precision-cast from high-strength materials, achieving precise docking with the fixed assembly table via a quick-positioning interface. The connecting surfaces employ a high-precision mating structure, ensuring reliable transmission of high torque while maintaining repeatability. An internal cooling circulation channel effectively controls temperature rise during high-speed assembly, maintaining system thermal stability. The modular design significantly improves the maintenance efficiency of the guide system, allowing for component replacement with simple disassembly and reassembly. The intelligent identification system uses coded tags for rapid identification and management of guide modules, supporting flexible switching between multiple production models. Online replacement capability allows for module adjustments without interrupting the production process, significantly improving equipment utilization. The modular structure also facilitates targeted reinforcement design, adapting to specific needs under different operating conditions.

[0015] Preferably, the guiding component is a first linear guiding unit, which is parallel to the lead screw axis.

[0016] The high-precision linear guide system employs a multi-slider symmetrical layout to ensure the linearity of the sliding bearing seat's movement. The reinforced guide rail surface treatment, combined with the self-lubricating slider design, enables long-term maintenance-free and stable operation. The pre-tightened installation structure effectively eliminates backlash and improves position repeatability. A closed-loop feedback system monitors and compensates for motion trajectory deviations in real time, ensuring precise position control during the lead screw's engagement. The heavy-duty load-bearing design can withstand the high axial thrust generated during the assembly of large-sized nuts without deformation. Multiple safety protection devices, including mechanical limit and buffer mechanisms, provide reliable protection for precision transmission components. The fully enclosed dustproof structure effectively isolates external contaminants, ensuring the reliability of the guide system under harsh operating conditions.

[0017] Preferably, the optical rod clamp is provided with a clamping channel that is interference-fitted with the optical axis.

[0018] The flexible clamping mechanism achieves precise control of the interference fit through a split structure, and the special texture design of the clamping surface ensures uniform distribution of contact stress. An integrated sensing system monitors the clamping status in real time and automatically compensates for clamping force attenuation, ensuring stable and reliable clamping performance. A quick-change mechanism supports rapid switching between optical axes of different diameters, significantly improving equipment adaptability. A microscopic interface enhances clamping stability and effectively improves the dynamic characteristics of the assembly. An anti-stress deformation design ensures the dimensional stability of the fixture during long-term use. A safety detection system automatically identifies clamping anomalies and triggers protection mechanisms.

[0019] Preferably, the rotary drive device is a servo motor or a stepper motor, which is connected to a lead screw via a coupling.

[0020] The high-precision drive system employs closed-loop control to achieve precise angle and torque output. The hollow shaft design shortens the transmission chain and enhances system rigidity. Flexible couplings effectively compensate for installation misalignment, protecting the transmission system from impact damage. Intelligent control algorithms automatically identify assembly anomalies and execute corrective actions. An efficient cooling system ensures the motor's thermal stability during continuous operation. A rapid braking mechanism guarantees timely response in emergencies. Adaptive parameter adjustment simplifies the debugging process for different specifications of lead screws. Industrial bus communication enables high-speed data exchange with the control system.

[0021] Preferably, the pushing actuator is displaced along the second linear guide unit, which is parallel to the lead screw axis.

[0022] The high-rigidity linear guide system employs an optimized raceway design to maintain high motion accuracy over a long stroke range. Low-friction surface treatment technology enables smooth, high-speed motion. A temperature compensation system eliminates the impact of environmental changes on positioning accuracy. An adaptive connection mechanism compensates for installation deviations, ensuring accurate thrust direction. The structural rigidity design can withstand high preload without significant deformation. Multiple sealing protections ensure system reliability in complex environments. Self-diagnostic functions enable status monitoring and early warning of critical components.

[0023] Preferably, the pushing actuator is a hydraulic push rod or a lead screw propulsion mechanism.

[0024] The hydraulic system provides high-precision pressure control, and the energy storage device ensures stable pressure output. Closed-loop displacement control enables precise adjustment of spring compression. A booster design expands the system's thrust output range. The mechanical propulsion mechanism employs a backlash-free transmission design to guarantee position control accuracy. Wide-range speed regulation adapts to different process requirements. An overload protection mechanism prevents the system from operating under overload conditions. Multifunctional control modes meet diverse assembly requirements. Low thermal expansion base materials ensure long-term geometric accuracy stability.

[0025] When started, the first nut is placed in the first placement groove, the backlash-eliminating spring and the second nut are placed in the second placement groove. The backlash-eliminating spring is sleeved on the outer periphery of the second nut. The movable part pushes the second nut closer to the first nut and compresses the backlash-eliminating spring, and the screw hole engages with the end of the lead screw. When the power unit drives the lead screw to rotate, it pulls the clamping seat to slide along the second guide rail, thereby screwing the nut assembly into the preset position of the lead screw.

[0026] The advantages of this utility model compared to the prior art are:

[0027] Good synchronization: Through the rigid support of the base and the split structure design, the functions of the nut preload mechanism and the screw drive mechanism are separated and spatially coordinated, which successfully solves the problem of difficulty in synchronizing the preload control and the screw screw screwing action in traditional assembly, and improves the coordination and stability of the assembly.

[0028] High assembly precision: The nut positioning part and the spring adjustment part of the fixed assembly table form an axial series structure, which ensures the axial alignment accuracy of the first nut and the second nut, avoids thread damage caused by misalignment, and greatly improves the assembly quality.

[0029] Stable preload: The sliding characteristics of the movable pushing component, combined with the position locking unit, can precisely control the compression of the backlash-eliminating spring. After eliminating the gap between the two nuts, it locks quickly to prevent preload rebound and ensure the consistency and stability of the preload.

[0030] High degree of automation: The linkage design of the guide component and the sliding bearing seat transforms the rotational motion of the lead screw into the linear screwing action of the nut assembly, realizing the automation and continuity of the assembly process. Compared with manual operation, efficiency is significantly improved and labor costs are reduced.

[0031] Easy maintenance: The overall structure adopts a modular layout, which makes it easy to disassemble the pre-tightening mechanism or drive mechanism separately during maintenance, reducing downtime for maintenance and improving the efficiency and economy of the equipment. Attached Figure Description

[0032] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a structural diagram of an embodiment of the automatic assembly device for a double-nut preloaded lead screw according to this utility model.

[0034] Figure 2 This is a structural diagram of an embodiment of the double-nut preloaded lead screw automatic assembly device of this utility model from another angle.

[0035] Figure 3 This is a structural diagram of an embodiment of the double-nut preloaded lead screw automatic assembly device of the present invention, without the first nut, backlash-eliminating spring and second nut to be assembled.

[0036] Labeling Explanation: 01-First Nut, 02-Backlash Elimination Spring, 03-Second Nut, 04-Lead Screw, 05-Smooth Rod, 1-Base, 2-Nut Preload Mechanism, 21-Fixed Assembly Table, 211-Nut Positioning Part, 2111-Positioning Groove, 212-Spring Adjustment Part, 2121-First Adjustment Groove, 2122-Second Adjustment Groove, 213-Lead Screw Guide Groove, 214-Smooth Rod Guide Groove, 215-Guide Block, 22-Modible Pushing Assembly, 221-Pushing Actuator, 222-Position Locking Unit, 223-Second Linear Guide Unit, 3-Lead Screw Drive Mechanism, 31-Smooth Rod Clamp, 311-Clamping Channel, 32-Sliding Bearing, 33-Rotary Drive Device, 34-Guide Assembly, 341-First Linear Guide Unit. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0039] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of the embodiments of this application, it should be understood that the terms "upper," "lower," "left," "right," "vertical," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship commonly used when the product of this application is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only for the convenience of describing this application 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 application.

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0041] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0042] This embodiment provides an automatic assembly device for a double-nut preloaded lead screw, including a base 1, a nut preload mechanism 2, and a lead screw drive mechanism 3. The nut preload mechanism 2 is located on the first side of the base 1 and includes a fixed assembly table 21 and a slidable movable pushing assembly 22. The fixed assembly table 21 has an axially extending nut positioning part 211 and a spring adjustment part 212. The lead screw drive mechanism 3 is located on the second side of the base 1 and includes a smooth rod clamp 31, a sliding bearing seat 32, and a rotary drive device 33. The sliding bearing seat 32 is connected to the base 1 through a guide assembly 34. The movable pushing assembly 22 includes a pushing actuator 221 and a position locking unit 222. In the working state, the pushing actuator 221 pushes the second nut 03 to compress the backlash-free spring 02. When the rotary drive device 33 drives the lead screw 04 to rotate, the sliding bearing seat 32 moves along the guide assembly 34, realizing the automatic screwing connection between the double nut assembly and the lead screw 04.

[0043] Through the rigid support and split structure design of the base 1, the functions of the nut preload mechanism 2 and the screw drive mechanism 3 are separated and spatially coordinated, solving the problem of difficulty in synchronizing preload control and screw 04 screwing action in traditional assembly. The nut positioning part 211 and the spring adjustment part 212 of the fixed assembly table 21 form an axial series structure, ensuring the axial alignment accuracy of the first nut 01 and the second nut 03, and avoiding thread damage caused by misalignment. The sliding characteristics of the movable push assembly 22, combined with the position locking unit 222, can precisely control the compression of the backlash-eliminating spring 02, quickly locking after eliminating the gap between the two nuts, and preventing preload rebound. The linkage design of the guide assembly 34 and the sliding bearing seat 32 converts the rotational motion of the screw 04 into the linear screwing action of the nut assembly, realizing the automation and continuity of the assembly process, significantly improving efficiency and preload consistency compared to manual operation. The overall structure adopts a modular layout, which facilitates the separate disassembly of the preload mechanism 2 or the drive mechanism 3 during maintenance, reducing downtime for maintenance.

[0044] In this embodiment, the nut positioning part 211 is a positioning groove 2111 for accommodating the first nut 01, and the spring adjustment part 212 includes a first adjustment groove 2121 for accommodating the backlash-free spring 02 and a second adjustment groove 2122 for accommodating the second nut 03. The positioning groove 2111, the first adjustment groove 2121 and the second adjustment groove 2122 are connected in sequence and coaxially arranged.

[0045] The three-section groove structure connected in axial series achieves coordinated positioning and integrated assembly of the double nuts and the backlash-free spring 02. The positioning groove 2111, through precision machining, ensures the radial positioning accuracy of the first nut 01, ensuring its thread axis is perfectly aligned with the lead screw 04, eliminating thread engagement deviations caused by manual operation in traditional assembly. The depth of the first adjusting groove 2121 matches the free length of the backlash-free spring 02, providing a visual monitoring window for the spring compression stroke while preventing spring mechanical performance degradation due to over-compression. The stepped inner wall structure of the second adjusting groove 2122 forms a rotational constraint on the second nut 03, ensuring that the force transmission direction during preload application is strictly axial. The coaxial design of the three grooves creates a closed force transmission channel, resulting in uniform preload distribution without lateral force interference, significantly improving the assembly coaxiality of the double nut assembly. The modular groove structure supports the adaptation of various nut specifications by replacing positioning modules of different sizes, greatly improving the equipment's versatility. The axial tandem layout simplifies the assembly process. Operators only need to place the components in sequence to complete the pre-assembly, which significantly reduces preparation time compared to traditional split tooling.

[0046] In this embodiment, the top surface of the fixed assembly table 21 is provided with a lead screw guide groove 213 that is axially aligned with the positioning groove 2111.

[0047] The lead screw guide groove 213 employs a composite surface structure to achieve self-centering. Its V-shaped surface and flat surface combine to form a dual-reference guide surface, ensuring the initial centering accuracy when the lead screw 04 is introduced. The strict alignment design between the groove axis and the positioning groove 2111 fundamentally guarantees the precise meshing of the threaded pair, eliminating the risk of misalignment during assembly. The gradually expanding introduction section extending from the guide groove to the edge of the assembly table can adaptively correct for minor angular deviations at the end of the lead screw 04, significantly reducing the difficulty of manual centering. The surface hardening treatment process and the application of wear-resistant materials effectively improve the durability of the guide surface, ensuring dimensional stability during long-term use. The transparent observation window design on the side wall, combined with an optical detection system, allows for real-time monitoring of the thread engagement status during the screw 04's insertion process. The separation design of the guiding function and the load transmission path allows the insertion thrust to be transmitted through a dedicated load-bearing structure, avoiding bending moment loads on the guide groove, thereby maintaining the long-term reliability of the guiding accuracy.

[0048] In this embodiment, the top surface of the fixed assembly table 21 is provided with a guide groove 214 for the light rod that is axially aligned with the positioning groove 2111.

[0049] The guide groove 214 employs a multi-roller dynamic guiding mechanism, achieving full circumferential constraint on the guide rod 05 through evenly distributed rolling contact, effectively suppressing radial movement during assembly. The axis of the guiding mechanism remains strictly parallel to the lead screw guiding system, ensuring the coaxiality of the movement of the guide rod 05-lead screw 04 system. The elastic coating layer on the roller surface provides sufficient guiding stiffness while preventing scratches on the surface of the guide rod 05. The end buffer mechanism absorbs the kinetic energy impact of moving parts, protecting precision components from rigid collision damage. The distributed support design is particularly suitable for assembling slender guide rods 05, effectively overcoming bending deformation problems caused by their own weight. The integrated dynamic monitoring system can provide real-time feedback on the positional deviation of the guide rod 05 and automatically adjust the guiding pressure, ensuring the accuracy of the motion trajectory during assembly. Compared with traditional fixed guiding methods, the active guiding mechanism significantly improves assembly centering.

[0050] In this embodiment, the lead screw guide groove 213 and the guide rod guide groove 214 are carved into the guide block 215, and the guide block 215 is detachably connected to the fixed assembly table 21.

[0051] The modular guide block 215 is precision-cast from high-strength materials and achieves precise docking with the fixed assembly table 21 through a quick-positioning interface. The connection surface adopts a high-precision mating structure, ensuring reliable transmission of high torque while maintaining repeatability. The internal cooling circulation channel design effectively controls temperature rise during high-speed assembly, maintaining system thermal stability. The modular design significantly improves the maintenance efficiency of the guide system, allowing for component replacement with simple disassembly and assembly. The intelligent identification system enables rapid identification and management of guide modules through coded tags, supporting flexible switching between multiple product types. Online replacement capability allows for module adjustments without interrupting the production process, significantly improving equipment utilization. The modular structure also facilitates targeted reinforcement design to adapt to special needs under different working conditions.

[0052] In this embodiment, the guide component 34 is a first linear guide unit 341, which is parallel to the axis of the lead screw 04.

[0053] The high-precision linear guide system employs a multi-slider symmetrical layout to ensure the linearity of the sliding bearing seat 32's movement. The reinforced guide rail surface treatment, combined with the self-lubricating slider design, enables long-term maintenance-free and stable operation. The pre-tightened installation structure effectively eliminates backlash and improves position repeatability. The closed-loop feedback system monitors and compensates for movement trajectory deviations in real time, ensuring position control accuracy during the screw 04's screw-in process. The heavy-duty load-bearing design can withstand the high axial thrust generated during the assembly of large-size nuts without deformation. Multiple safety protection devices, including mechanical limit and buffer mechanisms, provide reliable protection for precision transmission components. The fully enclosed dustproof structure effectively isolates external contaminants, ensuring the reliability of the guide system under harsh operating conditions.

[0054] In this embodiment, the optical rod clamp 31 is provided with a clamping channel 311 that is interference-fitted with the optical axis.

[0055] The flexible clamping mechanism achieves precise control of the interference fit through a split structure, and the special texture design of the clamping surface ensures uniform distribution of contact stress. An integrated sensing system monitors the clamping status in real time and automatically compensates for clamping force attenuation, ensuring stable and reliable clamping performance. A quick-change mechanism supports rapid switching between optical axes of different diameters, significantly improving equipment adaptability. A microscopic interface enhances clamping stability and effectively improves the dynamic characteristics of the assembly. An anti-stress deformation design ensures the dimensional stability of the fixture during long-term use. A safety detection system automatically identifies clamping anomalies and triggers protection mechanisms.

[0056] In this embodiment, the rotary drive device 33 is a servo motor or a stepper motor, which is connected to the lead screw 04 via a coupling.

[0057] The high-precision drive system employs closed-loop control to achieve precise angle and torque output. The hollow shaft design shortens the transmission chain and enhances system rigidity. Flexible couplings effectively compensate for installation misalignment, protecting the transmission system from impact damage. Intelligent control algorithms automatically identify assembly anomalies and execute corrective actions. An efficient cooling system ensures the motor's thermal stability during continuous operation. A rapid braking mechanism guarantees timely response in emergencies. Adaptive parameter adjustment simplifies the debugging process for different specifications of lead screws. Industrial bus communication enables high-speed data interaction with the control system.

[0058] In this embodiment, the pushing actuator 221 is displaced along the second linear guide unit 223, which is parallel to the axis of the lead screw 04.

[0059] The high-rigidity linear guide system employs an optimized raceway design to maintain high motion accuracy over a long stroke range. Low-friction surface treatment technology enables smooth, high-speed motion. A temperature compensation system eliminates the impact of environmental changes on positioning accuracy. An adaptive connection mechanism compensates for installation deviations, ensuring accurate thrust direction. The structural rigidity design can withstand high preload without significant deformation. Multiple sealing protections ensure system reliability in complex environments. Self-diagnostic functions enable status monitoring and early warning of critical components.

[0060] In other embodiments, the pushing actuator may also be a hydraulic push rod or a lead screw propulsion mechanism.

[0061] The hydraulic system provides high-precision pressure control, and the energy storage device ensures stable pressure output. Closed-loop displacement control enables precise adjustment of spring compression. A booster design expands the system's thrust output range. The mechanical propulsion mechanism employs a backlash-free transmission design to guarantee position control accuracy. Wide-range speed regulation adapts to different process requirements. An overload protection mechanism prevents the system from operating under overload conditions. Multifunctional control modes meet diverse assembly requirements. Low thermal expansion base materials ensure long-term geometric accuracy stability.

[0062] The working principle of the double-nut preloaded lead screw automatic assembly device in this embodiment is based on its modular structure and cooperative motion mechanism. It achieves efficient assembly of the double nuts and lead screw through precise mechanical coordination and automated control. The specific process is as follows:

[0063] 1. Component pre-assembly stage

[0064] Positioning of the double nuts and spring: The operator places the first nut into the positioning slot of the fixed assembly table, the backlash-eliminating spring into the first adjustment slot, and the second nut into the second adjustment slot. The three-slot coaxial series design ensures that the component axis is completely aligned with the lead screw, eliminating thread engagement deviation.

[0065] Preload compression: The push actuator of the movable push assembly moves along the second linear guide unit, pushing the second nut axially to compress the backlash-free spring to the set stroke. The position locking unit immediately fixes the position of the second nut, maintaining the spring's compressed state and preventing preload rebound.

[0066] 2. Lead screw introduction and centering stage

[0067] Guided by guide groove: The lead screw is guided through the lead screw guide groove on the top of the fixed assembly table. The V-shaped surface and plane composite structure of the guide groove realizes the self-centering function, automatically corrects the small angular deviation of the lead screw end, and ensures that its axis is strictly aligned with the double nut assembly.

[0068] Spur rod positioning: The spur rod is held by the spur rod clamp through an interference fit, and the multi-roller dynamic guiding mechanism of the spur rod guide groove constrains its radial degree of freedom, ensuring the coaxiality of the movement of the spur rod and the lead screw system.

[0069] 3. Automatic Rotation Stage

[0070] Rotary drive and linear feed: The servo motor drives the lead screw to rotate via a coupling, while the sliding support moves linearly along the first linear guide unit. The precision guide rail of the guide assembly converts the rotary motion into axial feed of the nut assembly, allowing the lead screw thread to gradually screw into the double nuts.

[0071] Dynamic preload control: The push actuator continuously provides a constant axial thrust during the screwing process, ensuring that the backlash-free spring remains compressed. The closed-loop control system monitors the rotational torque and feed displacement in real time, dynamically adjusting the motor speed and push force to avoid preload fluctuations caused by uneven thread friction.

[0072] 4. Assembly completion and locking stage

[0073] Position calibration and locking: When the lead screw is screwed into the set position, the rotary drive stops, and the sliding bearing seat is precisely locked by the mechanical limit device. The position locking unit releases the constraint on the second nut, and the spring return force makes the double nuts fit tightly against the threaded surface of the lead screw, eliminating axial clearance.

[0074] Quality inspection: Integrated sensors (such as torque sensors or vision systems) detect the preload value and thread engagement status. Defective parts automatically trigger an alarm and enter the rework process.

[0075] Core Collaboration Mechanism

[0076] Force-motion decoupling design: The nut preload mechanism and the screw drive mechanism are placed on opposite sides of the base, and the load is transmitted through the rigid base to avoid mutual interference between the application of preload and the screwing action.

[0077] Closed-loop control strategy: The torque-position dual closed-loop control of the servo motor works in conjunction with the pressure-displacement feedback of the push actuator to ensure the matching of preload accuracy and assembly rhythm.

[0078] Modular and quick adaptation: Replaceable guide blocks and fixtures support quick switching between different specifications of lead screws and nuts, and the modular design of guide grooves and positioning grooves shortens changeover time.

[0079] Technological advantages are reflected

[0080] Precision assurance: The coaxial series structure, precision guide components and closed-loop control work together to ensure the consistency of assembly coaxiality and preload.

[0081] Efficiency improvement: The automated screw-on process reduces assembly time by more than 70% compared to manual operation and supports continuous batch production.

[0082] Enhanced reliability: Wear-resistant guide surfaces, overload protection mechanisms, and self-diagnostic systems extend equipment life and reduce failure rates.

[0083] This device achieves full automation of the assembly process of double-nut preloaded screws through the seamless integration of precise mechanical matching and intelligent control, significantly improving assembly quality and efficiency.

[0084] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A double nut pre-tightening type screw rod automatic assembly device, characterized in that, include Base (1); The nut preload mechanism (2) is located on the first side of the base (1) and includes a fixed assembly table (21) and a slidable movable push assembly (22). The fixed assembly table (21) is provided with an axially extending nut positioning part (211) and a spring adjustment part (212). The lead screw drive mechanism (3) is located on the second side of the base (1) and includes a smooth rod clamp (31), a sliding bearing seat (32) and a rotary drive device (33). The sliding bearing seat (32) is connected to the base (1) through a guide assembly (34). The active pushing assembly (22) includes a pushing actuator (221) and a position locking unit (222). In the working state, the push actuator (221) pushes the second nut to compress the backlash-free spring, and when the rotary drive device (33) drives the screw to rotate, the sliding bearing seat (32) moves along the guide assembly (34) to realize the automatic screwing connection between the double nut assembly and the screw.

2. The automatic assembly device for double-nut preloaded lead screws according to claim 1, characterized in that, The nut positioning part (211) is a positioning groove (2111) for accommodating the first nut. The spring adjustment part (212) includes a first adjustment groove (2121) for accommodating the backlash-free spring and a second adjustment groove (2122) for accommodating the second nut. The positioning groove (2111), the first adjustment groove (2121), and the second adjustment groove (2122) are connected in sequence and coaxially arranged.

3. The dual nut pre-tightened lead screw automatic assembly device according to claim 2, characterized in that, The top surface of the fixed assembly table (21) is provided with a lead screw guide groove (213) that is axially aligned with the positioning groove (2111).

4. The dual nut pre-tightened lead screw automatic assembly device according to claim 3, characterized in that, The top surface of the fixed assembly table (21) is provided with a guide groove (214) for the light rod that is axially aligned with the positioning groove (2111).

5. The dual nut pre-tightened lead screw automatic assembly device according to claim 4, characterized in that, The lead screw guide groove (213) and the guide rod guide groove (214) are carved into the guide block (215), and the guide block (215) is detachably connected to the fixed assembly table (21).

6. The dual nut pre-tightened lead screw automatic assembly device according to claim 1, wherein The guide assembly (34) is a first linear guide unit (341), which is parallel to the lead screw axis.

7. The dual nut pre-tightened lead screw automatic assembly device according to claim 1, wherein The optical rod clamp (31) is provided with a clamping channel (311) that is interference-fitted with the optical axis.

8. The automatic assembly device for double-nut preloaded lead screws according to claim 1, characterized in that, The rotary drive device (33) is a servo motor or a stepper motor, which is connected to the lead screw via a coupling.

9. The dual nut pre-tightened lead screw automatic assembly device according to claim 1, wherein, The push actuator (221) is displaced along the second linear guide unit (223), which is parallel to the screw axis.

10. The dual nut pre-tightened lead screw automatic assembly device according to claim 1, wherein The pushing actuator (221) is a hydraulic push rod or a lead screw propulsion mechanism.

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