Full-revolute-pair parallel adjustable dry-friction angular-displacement-free damping device

Abstract

The invention relates to the technical field of damping devices, in particular to a full revolute pair parallel adjustable dry friction angular displacement-free damping device which comprises a mounting seat, a stable platform and at least one damper arranged between the mounting seat and the stable platform. The angular displacement-free mechanism branches are arranged between the mounting seat and the stable platform in parallel; a plurality of angular displacement-free mechanism branches of a full revolute pair structure are adopted, a mounting base and a stable platform are connected in parallel, and a double-parallelogram connecting rod mechanism composed of a middle rod, a side rod, an offset side rod and other components of each angular displacement-free mechanism branch is adopted; the two ends of the branch only translate and do not rotate during relative movement, and a pretightening force adjusting structure is designed between the main shaft and the base and used for actively controlling and changing the dry friction force of the revolute pair.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration damping devices, and in particular to a fully rotating pair parallel adjustable dry friction non-angular displacement vibration damping device. Background Art

[0002] In cutting-edge fields such as aerospace, precision optical instruments, and high-end equipment manufacturing, many core devices (such as optoelectronic pods, telemetry equipment, and inertial measurement units) have extremely stringent requirements for their attitude stability. Angular vibration or angular runout introduced by external environments (such as platform vibration) can severely impact the measurement accuracy, imaging quality, and overall performance of these devices. Therefore, developing vibration-damping devices that effectively isolate angular vibration and achieve zero angular displacement is crucial.

[0003] Currently, to achieve angular displacement-free motion characteristics (i.e., constraining three rotational degrees of freedom while retaining three translational degrees of freedom), existing vibration damping devices are often designed using spatial linkage mechanisms that incorporate a combination of multiple kinematic pairs, such as moving pairs, ball joints, or universal joints. However, these structures often present inherent problems: First, the combination of multiple types of kinematic pairs, especially moving pairs and ball joints, makes the device structure more complex. Errors generated during processing and assembly easily accumulate, and joint clearances are difficult to completely eliminate. This can lead to insufficient angular constraint stiffness, making the device prone to transient instability or motion jamming under impact or high-vibration conditions. Second, these complex structures also pose challenges to long-term reliability and maintenance.

[0004] Furthermore, the dry friction in traditional vibration damping devices is often an inherent byproduct of structural design and material selection, with a fixed and non-adjustable magnitude. However, in practical applications, the magnitude of the load and the spectral characteristics of the external vibration are constantly changing. This fixed dry friction makes it difficult to tailor the device's vibration damping performance to different operating conditions, preventing optimal damping under varying conditions. This significantly limits its application performance and universality. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a fully rotating pair parallel adjustable dry friction angular displacement-free vibration reduction device, which realizes high-load, high-reliability angular displacement-free motion, and gives the device the characteristic of actively adjusting the dry friction force, so that it can adapt to changing working conditions and optimize the vibration reduction performance.

[0006] The present invention is achieved through the following technical solutions: A fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device, comprising a mounting seat and a stabilizing platform, further comprising: at least one vibration damper disposed between the mounting base and the stabilizing platform; a plurality of non-angular displacement mechanism branches arranged in parallel between the mounting seat and the stabilizing platform; The non-angular displacement mechanism is a full rotation pair structure, which is used to constrain the rotational freedom of the stabilizing platform relative to the mounting seat and retain the three translational freedoms of the stabilizing platform relative to the mounting seat; At least one rotating pair in the branch of the non-angular displacement mechanism is provided with a preload adjustment structure for adjusting the dry friction force of the rotating pair.

[0007] Optionally, the shock absorbers are magnetorheological shock absorbers, and there are four of them, the number of the non-angular displacement mechanism branches is four, the four shock absorbers and the four non-angular displacement mechanism branches are arranged in sequence and distributed in a ring around the mounting seat and the center of the stabilizing platform.

[0008] Optionally, the non-angular displacement mechanism branch includes: at least one compound kinematic subassembly; Two rotational motion sub-assemblies, both ends of the composite motion sub-assembly are respectively connected to the two rotational motion sub-assemblies, and one of the rotational motion sub-assemblies is fixedly connected to the mounting seat, and the other rotational motion sub-assembly is fixedly connected to the stable platform.

[0009] Optionally, the rotational motion sub-assembly includes: a base and a main shaft, the base is fixedly connected to the mounting seat or the stable platform, the main shaft is parallel to the mounting seat and rotationally connected to the base, and the composite motion sub-assembly is connected to the main shaft.

[0010] Optionally, the compound motion subassembly comprises: middle rod; at least two side rods, wherein first ends of the two side rods are rotatably connected to the intermediate rod via a long axis, and second ends of the two side rods are rotatably connected to one of the main shafts via a short axis, wherein the side rods, the intermediate rods and the main shaft define a first parallelogram structure; At least two offset side rods, the first ends of the two offset side rods are rotatably connected to the middle rod through the long axis, the second ends of the two offset side rods are rotatably connected to another main shaft through the short axis, and the offset side rods, the middle rod and the main shaft define a second parallelogram structure.

[0011] Optionally, polytetrafluoroethylene composite bushings are provided between the long shaft and the intermediate rod, between the short shaft and the main shaft, and between the main shaft and the base.

[0012] Optionally, in the cooperation between the main shaft and the base, the effective length of the main shaft is shorter than the depth of the inner cavity of the base, and a preset gap for accommodating an adjustment gasket is formed between the two; The preload force adjustment structure includes: an end cover connected to the base, an adjustment washer and an adjustment screw. The end cover applies axial pressure to the adjustment washer through the adjustment screw to adjust the dry friction between the main shaft and the base.

[0013] Optionally, the side rod and / or the offset side rod are connected to the main shaft and the intermediate rod via a fastener assembly; Adjustment washers are provided between the side rods and / or the offset side rods and the main shaft and / or the intermediate rod.

[0014] Optionally, a thrust side rod is further provided on the intermediate rod; The thrust side rod is fixed to the intermediate rod through a fastening assembly and is used to axially limit the long shaft connected to the intermediate rod; The fastening assembly includes a fastening screw, a spring washer and a flat washer.

[0015] Optionally, the side rod is an arc-shaped structure with wide ends and narrow middle; and / or The offset side rod has a geometric shape with a central offset, which is used to reserve an avoidance space for the side rod during movement.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects: The present invention adopts multiple angular displacement-free mechanism branches with full rotational pair structures to connect the mounting base and the stable platform in parallel. Each of the angular displacement-free mechanism branches is a double parallelogram linkage mechanism composed of components such as an intermediate rod, a side rod and an offset side rod, which ensures that the two ends of the branch only undergo translation without rotation during relative movement. A preload adjustment structure is designed between the main shaft and the base to actively control and change the dry friction force of the rotational pair.

[0017] The present invention adopts a parallel layout of multiple angular displacement-free mechanism branches of full-rotating pairs, effectively avoiding defects such as unstable movement, sticking or reduced angular constraint accuracy caused by clearance, wear or lubrication problems of these moving pairs; by setting a preload adjustment structure, the dynamic characteristics of the device can be optimized according to changes in the weight of the load-bearing equipment or differences in the external vibration environment, so that it can exhibit optimal vibration reduction performance under various working conditions; by applying polytetrafluoroethylene composite bushings in each rotating pair and optimizing the geometric shape of the side rods and offset side rods, the inherent friction of the system is reduced and self-lubrication is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings illustrate exemplary embodiments of the present invention and, together with the description thereof, are used to explain the principles of the present invention. These drawings are included to provide a further understanding of the present invention, and the accompanying drawings are included in and constitute a part of this specification and do not constitute a limitation of the embodiments of the present invention.

[0019] Figure 1 The figure is a schematic structural diagram of a fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to the present invention.

[0020] Figure 2 It is a front view of a branch of the non-angular displacement mechanism according to the present invention.

[0021] Figure 3 It is a front view and AA cross-sectional view of a branch of the non-angular displacement mechanism according to the present invention.

[0022] Figure 4 BB is a front view and a cross-sectional view of a branch of the non-angular displacement mechanism according to the present invention.

[0023] Figure 5 2 is a side view of a branch of the non-angular displacement mechanism according to the present invention.

[0024] Figure 1: 1-stabilizing platform; 2-shock absorber; 3-mounting seat; 4-branch of the non-angular displacement mechanism; 401-intermediate rod; 402-main shaft; 403-base; 404-offset side rod; 405-M12 polytetrafluoroethylene composite long bushing; 406-long shaft; 407-side rod; 408-short shaft; 409-M3 flat washer; 410-M3 hexagon socket head screw; 411-M3 Spring washer; 412-adjusting washer; 413-M5 flat washer; 414-M5 spring washer; 415-M5 hexagon socket flat head screw; 416-thrust side rod; 417-M12 short PTFE composite bushing; 418-M25 PTFE composite bushing; 419-end cover; 420-M10 flat washer; 421-M10 hexagon socket cylindrical head screw; 422-M10 spring washer. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the relevant content and are not intended to limit the present invention.

[0026] It should also be noted that, for the convenience of description, only the parts related to the present invention are shown in the drawings.

[0027] In this application, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be interpreted broadly. For example, they may refer to fixed connection, detachable connection, or integration; they may refer to direct connection or indirect connection through an intermediate medium; they may refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0028] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0029] In the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0030] Example 1 The device disclosed in this embodiment is a mechanical system for connecting a fixed base (i.e., "mounting base 3") and a device that needs to maintain a stable posture (mounted on "stabilizing platform 1"). It allows the stabilizing platform 1 to perform translational motion in three-dimensional space to buffer and isolate linear vibrations from the mounting base 3, but at the same time strictly prohibits any form of rotation or tilt of the stabilizing platform 1.

[0031] like Figure 1 As shown, it includes a mounting base 3 and a stabilizing platform 1, between which the following are arranged in parallel: at least one vibration damper 2 disposed between the mounting base 3 and the stabilizing platform 1; A plurality of non-angular displacement mechanism branches 4 are arranged in parallel between the mounting seat 3 and the stabilizing platform 1 .

[0032] Parallel connection means that these components are independently connected between the mounting base 3 and the stabilizing platform 1 and jointly undertake the tasks of support, motion constraint and vibration reduction.

[0033] The function of the shock absorber 2 is to dissipate vibration energy. When relative translation occurs between the stabilizing platform 1 and the mounting base 3 due to vibration, the shock absorber 2 will generate a damping force in the opposite direction of the motion, converting the kinetic energy of the vibration into heat energy and dissipating it, thereby achieving the purpose of attenuating the vibration and restoring the stability of the stabilizing platform 1 as soon as possible.

[0034] The branch 4 of the non-angular displacement mechanism is a full rotational pair structure, which is used to constrain the rotational freedom of the stable platform 1 relative to the mounting base 3 and retain the three translational degrees of freedom of the stable platform 1 relative to the mounting base 3; Branch 4 of the non-angular displacement mechanism is a spatial linkage. When mounting base 3 and stabilizing platform 1 undergo relative displacement, it constrains all rotational degrees of freedom (pitch, roll, and yaw) of stabilizing platform 1, while simultaneously preserving its three translational degrees of freedom (forward, backward, left, right, and up and down). The result is that regardless of the vibrations of mounting base 3, stabilizing platform 1 maintains its initial attitude, preventing angular deflection.

[0035] At least one rotating pair in the non-angular displacement mechanism branch 4 is provided with a preload force adjustment structure for adjusting the dry friction force of the rotating pair.

[0036] The preload adjustment structure is an initial pressing force applied to the internal friction surface of the rotating pair, which directly determines the dry friction force of the rotating pair, that is, the resistance against its initial rotation or low-speed rotation.

[0037] This vibration damping device utilizes multiple parallel, non-angular displacement mechanism branches 4, comprised of purely rotational joints, to kinematically ensure that only three-degree-of-freedom pure translational motion occurs between the stabilizing platform 1 and the mounting base 3, fundamentally eliminating the transmission of angular vibration. In the event of translational motion, the shock absorber 2 dissipates the energy. Furthermore, a preload adjustment mechanism pre-sets or adjusts the dry friction of key rotational pairs, optimizing the overall dynamic response of the device to meet diverse vibration damping requirements.

[0038] Example 2 Based on the overall structure of the first embodiment, this embodiment provides a specific and preferred implementation scheme for the number and spatial layout of the vibration absorber 2 and each core component.

[0039] Shock absorbers 2 are four magnetorheological (MR) dampers. These are semi-active, intelligently controlled dampers filled with a special fluid called "MR fluid," which contains suspended magnetic particles. When a magnetic field is applied through an internal electromagnetic coil, the magnetic particles rapidly align into a chain-like structure, causing the fluid's viscosity to change dramatically within milliseconds, thereby altering the damping force of the shock absorber. This damping force can be controlled quickly and continuously in real time by adjusting the input current.

[0040] The number of the non-angular displacement mechanism branches 4 is four, and the four shock absorbers 2 and the four non-angular displacement mechanism branches 4 are arranged in sequence and spaced apart, and distributed in a ring around the center of the mounting seat 3 and the stabilizing platform 1 .

[0041] In terms of spatial arrangement, these eight components (the four zero-angular displacement mechanism branches 4 and the four vibration dampers 2) are arranged in a circular pattern around the central axis of the mounting base 3 and the stabilizing platform 1, and are spaced apart from each other. This highly symmetrical layout ensures that the restraining and damping forces acting on the stabilizing platform 1 are evenly distributed regardless of the horizontal direction of external vibration. This effectively avoids any additional torsional or tilting moments that may be generated by uneven force, further enhancing the zero-angular displacement performance of the device.

[0042] Example 3 This embodiment describes in detail the internal mechanical structure of the branch 4 of the non-angular displacement mechanism. Figure 2 、 Figure 3 、 Figure 4 and Figure 5 As shown, the non-angular displacement mechanism branch 4 comprises at least one composite kinematic subassembly and two rotational kinematic subassemblies. In the assembly, the composite kinematic subassembly is located in the middle, with its ends connected to the two rotational kinematic subassemblies, forming a "two ends - middle" series structure. The two rotational kinematic subassemblies at the ends are responsible for securing the outermost mounting base 3 and the stabilizing platform 1, respectively.

[0043] Both ends of the composite motion sub-assembly are connected to two rotational motion sub-assemblies respectively, and one of the rotational motion sub-assemblies is fixedly connected to the mounting seat 3 , and the other rotational motion sub-assembly is fixedly connected to the stabilizing platform 1 .

[0044] The rotational motion sub-assembly includes: a base 403 and a main shaft 402. The base 403 is fixedly connected to the mounting seat 3 or the stable platform 1. The main shaft 402 is parallel to the mounting seat 3 and is rotationally connected to the base 403. The composite motion sub-assembly is connected to the main shaft 402.

[0045] The base 403 is a fixed bracket, which is firmly mounted on the external mounting base 3 or the stable platform 1. The main shaft 402 is a main rotating shaft, which is rotatably mounted in the base 403, and its axis is parallel to the plane of the mounting base 3.

[0046] The essence of the compound motion subassembly is an H-type connecting rod system consisting of two parallelogram mechanisms, including: An intermediate rod 401 serving as a central common member thereof; At least two side rods 407, wherein first ends of the two side rods 407 are rotatably connected to the middle rod 401 via a long axis 406, and second ends of the two side rods 407 are rotatably connected to one of the main shafts 402 via a short axis 408, and the side rods 407, the middle rod 401 and the main shaft 402 define a first parallelogram structure; At least two offset side rods 404, the first ends of the two offset side rods 404 are rotatably connected to the middle rod 401 through the long axis 406, and the second ends of the two offset side rods 404 are rotatably connected to another main shaft 402 through the short axis 408. The offset side rods 404, the middle rod 401 and the main shaft 402 define a second parallelogram structure.

[0047] When the device moves, the geometric constraints of these two parallelograms ensure that the upper spindle 402 can only translate, not rotate, relative to the lower spindle 402. Ultimately, this complex mechanism, composed entirely of purely rotational joints, achieves "zero angular displacement" motion at the branch level.

[0048] In order to further ensure the structural stability of the entire device under complex loads, this embodiment proposes a preferred layout: the number of compound motion sub-assemblies (i.e., H-type mechanisms) is set to two, and they are symmetrically arranged at both ends of the two core rotating shafts, the long axis 406 and the short axis 408.

[0049] The original single-piece H-shaped linkage has been upgraded to a bilaterally symmetrical, parallel "double-link" or "box-type" structure. This connection layout, known in engineering as "double shear," exponentially improves the structure's resistance to torsion and lateral bending compared to a single-point connection, ensuring that the mechanism does not deform due to stress during movement, greatly enhancing the rigidity and precision of the entire non-angular displacement mechanism branch 4.

[0050] In addition, polytetrafluoroethylene composite bushings are provided between the long shaft 406 and the intermediate rod 401, between the short shaft 408 and the main shaft 402, and between the main shaft 402 and the base 403. Polytetrafluoroethylene is an engineering plastic with a low friction coefficient. The use of polytetrafluoroethylene composite bushings has two main advantages: first, the extremely low friction characteristics make the entire mechanism move smoothly and respond sensitively, and minimize nonlinear friction interference; second, the self-lubricating characteristics, which can maintain low friction operation for a long time without the need for additional lubricating oil or grease, greatly improving the reliability and durability of the device and significantly reducing maintenance costs. Example 4 This embodiment provides a specific implementation method and working principle of the preload force adjustment structure.

[0051] In the cooperation between the main shaft 402 and the base 403, the effective length of the main shaft 402 is shorter than the inner cavity depth of the base 403, forming a preset gap between the two for accommodating the adjustment gasket 412; The preload adjustment structure includes: an end cover 419 connected to the base 403, an adjustment gasket 412 and an adjustment screw. The end cover 419 applies axial pressure to the adjustment gasket 412 through the adjustment screw to adjust the dry friction between the main shaft 402 and the base 403.

[0052] When the operator tightens the adjusting screw to secure the end cap 419, it compresses the adjusting shim 412 inward. This pressure is directly transmitted through the shim to the end face of the spindle 402, creating an axial thrust and a preload. This preload forces the radial surface of the spindle 402 into closer contact with the inner wall of the base 403 (and the bushing between them), thereby directly increasing the "dry friction" between them. Therefore, by selecting a combination of adjusting shims 412 of varying thicknesses or controlling the final tightening torque of the adjusting screw, the dry friction of the device can be precisely set or varied.

[0053] In one specific structural example, the base 403 is not a closed cylinder, but rather a structure with two left and right support ears, similar to a U-shaped bracket. The main shaft 402 is mounted across and between these two support ears. Accordingly, the end cap 419 is also designed as a cover plate that can be fixed to the end surfaces of the two support ears.

[0054] Side rods 407 and / or offset side rods 404 are connected to main shaft 402 and intermediate rod 401 via a fastener assembly comprising a setscrew, spring washer, and flat washer. The setscrew provides the primary axial clamping force; the spring washer prevents the screw from loosening due to vibration through its elasticity; and the flat washer increases contact area, dissipates pressure, and protects the surfaces of the connected parts.

[0055] Adjustment gaskets are provided between the side rod 407 and / or the offset side rod 404 and the main shaft 402 and / or the intermediate rod 401. By selecting gaskets of different thicknesses, the axial movement of the connecting rod on the rotating shaft can be controlled extremely accurately, eliminating the cumulative assembly error and ensuring that the clearances of the various moving pairs inside the entire H-type mechanism are minimized.

[0056] A thrust side rod 416 is also provided on the intermediate rod 401; the thrust side rod 416 is fixed to the intermediate rod 401 by a fastening assembly, and is used to axially limit the long shaft 406 connected to the intermediate rod 401; the thrust side rod 416 axially limits the long shaft 406, defines the axial position of the long shaft 406, prevents it from moving, and can withstand the axial thrust that may be generated during the movement.

[0057] In addition, this embodiment can also adjust the friction between the side rod 407 and the offset side rod 404 and the main shaft 402 and the intermediate rod 401 by adjusting the pre-tightening force of the fastening screw, thereby further adjusting the dry friction of each rotating pair in the compound motion pair assembly.

[0058] Side rod 407 is an arc-shaped structure, wider at both ends and narrower in the middle. This arc-shaped structure means that the overall outline of side rod 407 is not a straight line, but rather exhibits a certain curvature. This arc allows the rod to "circumvent" potential interference areas during swinging, thereby providing a wider range of motion for the entire mechanism within a limited space, thereby increasing the travel limit of the device. The wider cross-section at both ends ensures strength and rigidity at the connection with the rotating shaft, while the stress in the middle is relatively small. This effectively reduces the weight of the connecting rod itself without sacrificing the strength of key parts, thereby reducing the inertia of the entire motion system. The offset side rod 404 has a geometric shape with a middle offset, which is used to reserve avoidance space for the side rod 407 during movement. The middle offset can be understood as a non-planar, three-dimensional structure similar to a "Z" or "S" shape. The middle part of the rod has a spatial misalignment or offset relative to the connecting axis at both ends. During the movement of the H-type mechanism, the movement trajectories of the side rod 407 and the offset side rod 404 will intersect. Without this three-dimensional offset design, the two sets of connecting rods will physically collide when they move to a certain position, thereby severely limiting the mobility of the mechanism. By setting an offset for the offset side rod 404, it is ensured that it can perfectly "dodge" the side rod 407 during movement, and the two can move smoothly and intertwine without interference.

[0059] Example 5 This embodiment aims to provide a complete and specific device example that integrates all the aforementioned technical features.

[0060] Refer to the attached Figure 1 The device consists of a stable platform 1, a mounting base 3, four magnetorheological dampers 2, and four non-angular displacement mechanism branches 4. These four functional modules are connected into an organic whole using standard fasteners. The four dampers 2 and four mechanism branches are connected in parallel between the mounting base 3 and the stable platform 1.

[0061] A detailed enumeration of all the parts that make up the single "branch 4 (4) of the non-angular displacement mechanism" is provided. The main structural parts include: an intermediate rod 401, two main shafts 402, four bases 403, four offset side rods 404, two long shafts 406, two side rods 407, four short shafts 408, two thrust side rods 416, and four end covers 419.

[0062] In order to achieve low-friction precision rotation, it is equipped with a variety of high-performance bushings, including: 2 M12 PTFE composite long bushings 405, 4 M12 PTFE composite short bushings 417 and 4 M25 PTFE composite bushings 418.

[0063] In addition, it also includes various standard parts for adjustment and tightening, such as: 16 adjusting washers 412; and multiple sets of fasteners for connecting different parts, consisting of M3 flat washers 409, M3 hexagon socket cylindrical head screws 410, M3 spring washers 411, M5 flat washers 413, M5 spring washers 414, M5 hexagon socket flat head screws 415, M10 flat washers 420, M10 hexagon socket cylindrical head screws 421, and M10 spring washers 422. Fastening components of different sizes are selected according to different locations.

[0064] Among the above parts, the middle rod 401, the side rod 407, the offset side rod 404, the long shaft 406, the thrust side rod 416 and the related bushings and fasteners together form a core "H-type mechanism", as shown in the attached figure. Figure 3 shown.

[0065] Kinematic principle: The essence of the H-type mechanism is composed of two parallelogram motion pairs. This geometric constraint is the fundamental guarantee for achieving motion without angular displacement.

[0066] Design Optimization: The sidebar 407 in this mechanism is designed with an arc shape, wide at both ends and narrow in the middle, to maximize travel. All internal rotating pairs utilize bushings, such as the M12 PTFE long bushing and the M12 PTFE composite short bushing 417, to achieve self-lubrication and low friction.

[0067] The H-shaped mechanism is connected to the base 403 as a support through the main shaft 402 to form a revolving pair. The revolving pair is the main load-bearing joint of the entire branch, and an M25 polytetrafluoroethylene composite bushing 418 is provided inside the revolving pair.

[0068] To achieve adjustable friction, the revolute pair is designed so that the effective length of spindle 402 is shorter than the internal depth of base 403. This length difference creates a gap to accommodate adjustment spacer 412. During assembly, axial pressure is applied through fasteners such as end cap 419 and M10 hexagon socket head cap screw 421, thereby varying the normal pressure acting on M25 polytetrafluoroethylene composite bushing 418, ultimately achieving adjustment of dry friction.

[0069] It should be understood by those skilled in the art that the above embodiments are merely for the purpose of illustrating the present invention clearly, and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications may be made based on the above invention, and these changes or modifications are still within the scope of the present invention.

Claims

1. A fully rotating parallel adjustable dry friction non-angular displacement vibration reduction device, comprising a mounting seat (3) and a stabilizing platform (1), characterized in that: Also includes: at least one vibration damper (2) disposed between the mounting seat (3) and the stabilizing platform (1); A plurality of non-angular displacement mechanism branches (4) arranged in parallel between the mounting seat (3) and the stabilizing platform (1); The non-angular displacement mechanism branch (4) is a full rotational pair structure, which is used to constrain the rotational freedom of the stabilizing platform (1) relative to the mounting seat (3) and retain the three translational freedoms of the stabilizing platform (1) relative to the mounting seat (3); At least one rotating pair in the non-angular displacement mechanism branch (4) is provided with a preload adjustment structure for adjusting the dry friction force of the rotating pair.

2. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 1, characterized in that: The vibration dampers (2) are magnetorheological vibration dampers (2), and the number of the dampers is four. The number of the non-angular displacement mechanism branches (4) is four. The four vibration dampers (2) and the four non-angular displacement mechanism branches (4) are arranged in sequence and spaced apart, and are distributed in a ring around the center of the mounting seat (3) and the stabilizing platform (1).

3. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 1, characterized in that: The non-angular displacement mechanism branch (4) comprises: at least one compound kinematic subassembly; Two rotational motion sub-assemblies, both ends of the composite motion sub-assembly are respectively connected to the two rotational motion sub-assemblies, and one of the rotational motion sub-assemblies is fixedly connected to the mounting seat (3), and the other rotational motion sub-assembly is fixedly connected to the stable platform (1).

4. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 3, characterized in that: The rotational motion subassembly comprises: a base (403) and a main shaft (402); the base (403) is fixedly connected to the mounting seat (3) or the stabilizing platform (1); the main shaft (402) is parallel to the mounting seat (3) and rotationally connected to the base (403); and the composite motion subassembly is connected to the main shaft (402).

5. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 4, characterized in that: The compound motion subassembly comprises: middle rod (401); at least two side rods (407), wherein the first ends of the two side rods (407) are rotatably connected to the intermediate rod (401) via a long axis (406), and the second ends of the two side rods (407) are rotatably connected to one of the main shafts (402) via a short axis (408), and the side rods (407), the intermediate rod (401) and the main shaft (402) define a first parallelogram structure; At least two offset side rods (404), the first ends of the two offset side rods (404) are rotatably connected to the middle rod (401) through the long axis (406), the second ends of the two offset side rods (404) are rotatably connected to another main axis (402) through the short axis (408), and the offset side rods (404), the middle rod (401) and the main axis (402) define a second parallelogram structure.

6. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 5, characterized in that: Polytetrafluoroethylene composite bushings are provided between the long shaft (406) and the intermediate rod (401), between the short shaft (408) and the main shaft (402), and between the main shaft (402) and the base (403).

7. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 5, characterized in that: In the cooperation between the main shaft (402) and the base (403), the effective length of the main shaft (402) is shorter than the inner cavity depth of the base (403), and a preset gap for accommodating an adjustment gasket (412) is formed between the two. The preload force adjustment structure comprises: an end cover (419) connected to the base (403), an adjustment gasket (412) and an adjustment screw, wherein the end cover (419) applies axial pressure to the adjustment gasket (412) via the adjustment screw to adjust the dry friction between the main shaft (402) and the base (403).

8. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 5, characterized in that: The side rod (407) and / or the offset side rod (404) are connected to the main shaft (402) and the intermediate rod (401) via a fastener assembly; An adjustment spacer is provided between the side rod (407) and / or the offset side rod (404) and the main shaft (402) and / or the intermediate rod (401).

9. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 5, characterized in that: A thrust side rod (416) is also provided on the intermediate rod (401); The thrust side rod (416) is fixed to the intermediate rod (401) via a fastening assembly and is used to axially limit the long shaft (406) connected to the intermediate rod (401); The fastening assembly includes a fastening screw, a spring washer and a flat washer.

10. The fully rotating pair parallel adjustable dry friction non-angular displacement vibration reduction device according to claim 5, characterized in that: The side rod (407) is an arc-shaped structure with wide ends and narrow middle; and / or The offset side rod (404) has a geometric shape with a central offset, which is used to reserve an avoidance space for the side rod (407) during movement.

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