Ball screw type limiting device

Abstract

The invention provides a ball screw type limiting device. The device comprises an outer sleeve, a ball screw arranged in the outer sleeve and a limiting energy dissipation assembly arranged between the ball screw and the outer sleeve, and the limiting energy dissipation assembly comprises a limiting sleeve matched with the telescopic end of the inner side of the ball screw in a limiting mode and two first energy dissipation units arranged at the two ends of the limiting sleeve correspondingly. The first energy consumption unit comprises a rotary friction sleeve with a friction rotor, a friction block which abuts against and rubs against the friction rotor when the rotary friction sleeve rotates, and a force application spring which enables the friction block to press the friction rotor when friction energy consumption is conducted, and the rotary friction sleeve is fixedly connected with a nut of an axially-limited ball screw. And the force application spring is connected between the limiting sleeve and the friction block. The device has the advantages of limiting, excellent vibration reduction and energy consumption functions, compact structure and the like.

Description

Technical Field

[0001] The present invention relates to the field of bridge limiting, and in particular to a ball screw type limiting device. Background Art

[0002] Existing structural limit devices for bridges and other structures mainly include rigid limit blocks and elastic limit components (such as rubber springs, disc springs, steel wire ropes and other elastic components). Among them, the rigid limit block has a simple structure, but when it relies on the rigid limit block to play a limiting role, it will generate a large collision force. The force generated by the rigid limit block is uncontrollable, resulting in structural damage, poor structural reliability and safety, and is not suitable for longitudinal limit of bridges that require large strokes and large spans. The elastic limit component provides elastic limit force for the bridge, but it has the following problems: (1) The elastic limit component only converts the kinetic energy of the bridge movement into elastic potential energy and releases it, so that the greater the displacement of the bridge, the greater the spring restoring force, and the greater the elastic potential energy released by the elastic limit component. It does not have the function of absorbing energy and absorbing energy and reducing vibration; (2) The maximum bearing capacity of the disc spring and rubber spring is small. When it is necessary to achieve the limit of a large stroke of the bridge, the disc spring and rubber spring need to be set to a very long length, making it impossible to apply it to the limit of a large stroke of the bridge. It can be seen that the existing structural limit device has no energy dissipation capacity or poor energy dissipation capacity, and cannot achieve the limit of a large stroke of the bridge.

[0003] However, existing bridge friction dampers are usually constant-force friction dampers, which makes the friction force of the bridge very large even at small displacements, easily causing fatigue damage to the components; at the same time, existing bridge friction dampers do not have a limiting function and cannot be used for effective limiting of the structure at different displacements, resulting in poor structural safety and reliability. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a ball screw type limiting device which has both limiting and excellent vibration reduction and energy dissipation functions and a compact structure.

[0005] In order to solve the above technical problems, the technical solution proposed by the present invention is: A ball screw type limiting device comprises an outer sleeve, a ball screw arranged in the outer sleeve, and a limiting energy absorbing component arranged between the ball screw and the outer sleeve, the limiting energy absorbing component comprising a limiting sleeve that cooperates with the inner telescopic end of the ball screw, and two groups of first energy absorbing units respectively arranged at the two ends of the limiting sleeve, the first energy absorbing unit comprising a rotating friction sleeve with a friction rotor, a friction block that presses against the friction rotor when the rotating friction sleeve rotates, and a force spring that presses the friction rotor when friction energy is consumed, the rotating friction sleeve is fixedly connected to the nut of the axially limited ball screw; the force spring is connected between the limiting sleeve and the friction block.

[0006] As a further improvement of the above technical solution: A limit piece is provided at the inner telescopic end of the screw of the ball screw, and limit platforms are provided at both ends of the limit sleeve for limiting the position of the limit piece. The sum of the initial distance between the limit piece and the limit platform and the maximum compression amount of the force spring is greater than or equal to the preset maximum displacement of the structure to be damped.

[0007] The force spring is in an unprestressed state in the initial position. When the actual axial displacement of the ball screw is less than the initial distance between the limit member and the limit platform, the force spring is not compressed, and the limit force generated by the limit energy dissipation component is zero; when the actual axial displacement of the ball screw is greater than the initial distance between the limit member and the limit platform, the limit member and the limit platform are limitedly matched, and the limit energy dissipation component generates a limit force proportional to the actual axial displacement of the ball screw.

[0008] The limiting force generated by the limiting energy dissipation component and the actual axial displacement of the ball screw satisfy the following relationship: in, The limiting force generated by the limiting energy-consuming component, is the initial distance between the limiter and the limit platform, is the actual axial displacement of the ball screw, is the velocity direction of the ball screw, It is the ratio of the axial force converted by the ball screw to the axial pressure exerted on the friction rotor. is the stiffness of the force spring, is the axial force converted by the ball screw, is the axial pressure on the friction rotor, is the friction coefficient of the friction rotor, is the number of friction surfaces of the friction rotor, is the lead of the ball screw, is the outer diameter of the friction rotor, is the inner diameter of the friction rotor.

[0009] One end of the limiting sleeve is arranged between the outer sleeve and the friction block through circumferential limitation and axial movement by a limiting key, and the other side end of the limiting sleeve is installed on the corresponding friction block through circumferential limitation and axial movement by a limiting key.

[0010] One end of the force spring abuts or is fixedly connected to the friction block, and the other end of the force spring abuts against the limit platform. When one of the force springs is compressed, the end of the other force spring is separated from the friction block or the limit platform.

[0011] The energy dissipation component also includes a second energy dissipation unit, which includes a conductor plate and an energy dissipation permanent magnet arranged relatively to each other. The energy dissipation permanent magnets are arranged in an array. One of the conductor plate and the energy dissipation permanent magnet is provided on the rotating friction sleeve, and the other is provided on the outer sleeve.

[0012] The nut of the ball screw is axially limited in the outer sleeve by a first thrust bearing, and the rotating friction sleeve is installed in the outer sleeve by a second thrust bearing.

[0013] Compared with the prior art, the advantages of the present invention are: The friction energy dissipation of the present invention has two energy dissipation paths, one of which is: using the nut that limits the axial position of the ball screw to fix the rotating friction sleeve equipped with a friction rotor to the nut, when the screw of the ball screw moves axially, the nut does not move axially but rotates circumferentially, thereby driving the friction rotor of the rotating friction sleeve to rotate, and the friction block is pressed against the friction rotor by the force spring, so that the friction rotor and the friction block generate relative friction, thereby realizing friction energy dissipation.

[0014] Another energy dissipation path is: utilizing the axial movement of the screw of the ball screw, two groups of first energy dissipation units are respectively set at both ends of the limit sleeve, that is, the first energy dissipation unit is provided with a limit sleeve, a friction block and a force spring, and the limit sleeve can cooperate with the telescopic end of the ball screw to realize the limiting function of the structure; the force spring is connected between the limit sleeve and the friction block to provide the friction block with a force to press the friction rotor when the limit sleeve is limited and axial movement is generated. It allows the force of the bridge and other structures during axial vibration to act on the friction rotor in sequence through the screw, limit sleeve, force spring and friction block of the ball screw, so that the pressure of the friction rotor increases and the friction rotor rotates, which generates a friction torque that increases with displacement. The friction torque is fed back to the screw through the nut, thereby generating an axial damping force that increases with displacement, that is, the axial force converted by the friction torque through the ball screw is much greater than the elastic force of the force spring itself, thereby further limiting the axial movement of structures such as bridges connected to the screw and achieving better vibration reduction and energy dissipation effects.

[0015] It can be seen that the present invention utilizes the structural motion characteristics of the ball screw and, through ingenious structural design, realizes that structures such as bridges provide limiting force through friction and at the same time consume energy through friction torque, thereby avoiding the problem that existing limiting devices and dampers cannot have both limiting and energy consumption functions at the same time, and greatly improves the effect of vibration reduction and energy consumption, thereby ensuring the reliable and safe operation of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein: Figure 1 It is a structural schematic diagram of the ball screw type limiting device of the present invention; Figure 2 Schematic diagram of the structure of the ball screw type limiting device of the present invention in a specific application; Figure 3 It is a curve diagram showing the relationship between the actual axial displacement of the ball screw limiter and the limit force generated by the limit energy dissipation component of the present invention.

[0017] The numbers in the figure represent: 1. Outer sleeve; 2. Ball screw; 21. Nut; 22. Screw; 23. Limiting member; 3. Limiting energy-absorbing component; 31. First energy-absorbing unit; 311. Limiting sleeve; 3111. Limiting platform; 312. Rotating friction sleeve; 3121. Friction rotor; 313. Friction block; 314. Force spring; 32. Second energy-absorbing unit; 321. Conductor plate; 322. Energy-absorbing permanent magnet; 4. First thrust bearing; 5. Second thrust bearing; 6. Bridge; 61. Beam support; 7. Bridge tower platform; 71. Platform support. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereby.

[0019] Figure 1 and Figure 2 The present invention illustrates an embodiment of a ball screw-type position limiting device, which can be used for position limiting and vibration reduction in structures such as bridge 6. The position limiting device is disposed at the bottom or both sides of bridge 6. One end of the position limiting device is connected to bridge 6 via a beam support 61, and the other end is connected to a tower platform 7 via a platform support 71. In this embodiment, the ball screw-type position limiting device includes an outer sleeve 1, a ball screw 2, and a position limiting energy dissipation assembly 3. The ball screw 2 is disposed within the outer sleeve 1; the position limiting energy dissipation assembly 3 is disposed between the ball screw 2 and the outer sleeve 1; and the position limiting energy dissipation assembly 3 includes a position limiting sleeve 311 and two sets of first energy dissipation units 31. Among them, the limit sleeve 311 is fixedly installed on the outer sleeve 1. When the structure vibrates, the limit sleeve 311 cooperates with the inner telescopic end of the ball screw 2 when the screw 22 of the ball screw 2 moves to a certain distance. The inner telescopic end of the ball screw 2 is the telescopic end located inside the outer sleeve 1; the two groups of first energy consumption units 31 are respectively arranged at the two ends of the limit sleeve 311, which are used to limit the structural vibration.

[0020] In this embodiment, the first energy dissipation unit 31 comprises a rotating friction sleeve 312, a friction block 313, and a force spring 314. The rotating friction sleeve 312 is fixedly connected to the nut 21 of the axially limited ball screw 2. The rotating friction sleeve 312 includes a friction rotor 3121, which rotates synchronously with the rotating friction sleeve 312 as the nut 21 rotates circumferentially. The friction rotor 3121 provides friction torque when the structure vibrates. This friction torque is converted into an equivalent axial force by the ball screw 2. This friction torque is amplified when converted into axial force by the ball screw 2, achieving an axial damping force that varies with the vibration displacement. The friction block 313 rubs against the friction rotor 3121 when the rotating friction sleeve 312 rotates. The force spring 314 is connected between the limiting sleeve 311 and the friction block 313. The force spring 314 compresses when the friction block 313 dissipates friction energy, thereby compressing the friction rotor 3121 and increasing the pressure on the friction rotor 3121.

[0021] The friction energy dissipation of the present invention has two energy dissipation paths, one of which is: using the nut 21 that limits the axial position of the ball screw 2, the rotating friction sleeve 312 provided with the friction rotor 3121 is fixedly connected to the nut 21. When the screw 22 of the ball screw 2 moves axially, the nut 21 does not move axially but rotates circumferentially, thereby driving the friction rotor 3121 of the rotating friction sleeve 312 to rotate. The friction block 313 is pressed against the friction rotor 3121 by the force spring 314, so that the friction rotor 3121 and the friction block 313 generate relative friction, thereby realizing friction energy dissipation.

[0022] Another energy dissipation path is: utilizing the axial movement of the screw rod 22 of the ball screw 2, two sets of first energy dissipation units 31 are respectively provided at both ends of the limiting sleeve 311, that is, the first energy dissipation unit 31 is provided with a limiting sleeve 311, a friction block 313 and a force spring 314, and the limiting sleeve 311 can cooperate with the telescopic end of the ball screw 2 to realize the limiting function of the structure; the force spring 314 is connected between the limiting sleeve 311 and the friction block 313 to provide the friction block 313 with a force to press the friction rotor 3121 after the limiting sleeve 311 is limited and axial movement is generated, which makes the force of the structure such as the bridge 6 during axial vibration less The screw 22, the limit sleeve 311, the force spring 314 and the friction block 313 of the ball screw 2 act on the friction rotor 3121 in sequence, so that the pressure of the friction rotor 3121 increases and the friction rotor 3121 rotates, which generates a friction torque that increases with the displacement. The friction torque is fed back to the screw 22 through the nut 21, thereby generating an axial damping force that increases with the displacement, that is, the axial force converted by the friction torque through the ball screw 2 is much greater than the elastic force of the force spring 314 itself, thereby further limiting the axial movement of structures such as the bridge 6 connected to the screw 22 and achieving better vibration reduction and energy consumption effects.

[0023] It can be seen that the present invention utilizes the structural motion characteristics of the ball screw 2 and, through ingenious structural design, realizes that structures such as the bridge 6 provide limiting force through friction and at the same time consume energy through friction torque, thereby avoiding the problem that existing limiting devices and dampers cannot have both limiting and energy consumption functions, and greatly improves the effect of vibration reduction and energy consumption, thereby ensuring the reliable and safe operation of the structure.

[0024] The present invention transmits the force of the structure to between the friction rotor 3121 and the friction block 313 through the force spring 314, and finally converts the elastic force of the force spring 314 into friction force. Compared with the existing elastic components, it can absorb energy and avoids the problem of the elastic components converting kinetic energy into elastic potential energy and then releasing it. The present invention can realize the limiting function through the elastic components while not releasing energy when the elastic components are reset. Instead, it absorbs energy by converting it into friction force. Compared with the existing elastic components, the present invention has the effect of reducing vibration and consuming energy.

[0025] Compared with traditional friction dampers, the present invention has displacement-related characteristics and realizes a friction force related to displacement, that is, when the displacement of structures such as bridge 6 becomes smaller, the pressure on the friction rotor 3121 acted upon by the force spring 314 and the friction block 313 also becomes smaller, and the friction torque of the friction rotor 3121 becomes smaller; when the displacement of the structure becomes larger, the friction torque also increases, avoiding the problem of constant friction damping force and easy damage of components in traditional friction dampers. The friction force of the present invention can be adjusted with the displacement of the structure, thereby reducing friction energy consumption and avoiding damage to components when the displacement of structures such as bridge 6 is small, and increasing friction energy consumption and ensuring energy consumption effect when the displacement of the structure is large.

[0026] Compared with traditional friction dampers, the invention can realize the damping energy dissipation function and the adjustable friction damping function, and at the same time, can realize the effective limitation of external components (such as bridge 6) at different displacements, thereby better ensuring effective vibration reduction and safe and reliable operation of the structure.

[0027] The present invention utilizes the amplifying effect of the ball screw 2 to amplify the small torque of the nut 21 into a large axial tonnage output force. At the same time, the present invention does not rely on material deformation when limiting the large stroke of structures such as bridges 6. Compared with the elastic limiting component relying on material deformation for limiting, the space occupied is greatly reduced, and its layout is compact, so that the present invention can be effectively applied to the vibration reduction and limiting of large-tonnage, large-stroke structures. For example, for a traditional disc spring or rubber spring, assuming its compressibility is 40%, if a stroke of ±1m is required, the original length of the spring on one side needs to be 5m, and the length of the springs on both sides and the piston rod after pre-compression assembly will exceed 4×2+1=9m. However, the output force of the present invention does not rely on material deformation, and the total length of the device only needs to be 3×1m+the structural length (4~4.5m) to achieve the same ±1m stroke.

[0028] Furthermore, a limit piece 23 is provided at the telescopic end of the screw 22 of the ball screw 2, and a limit platform 3111 is provided at both ends of the limit sleeve 311. The limit platform 3111 can cooperate with the limit piece 23 when the screw 22 moves axially. The sum of the initial distance between the limit piece 23 and the limit platform 3111 and the maximum compression amount of the force spring 314 is greater than or equal to the preset maximum displacement of the structure to be damped, so that the limit device of the present invention has an excellent vibration damping effect before the structure reaches the maximum displacement, and avoids the force spring 314 from generating pressure loss within the preset maximum displacement, thereby further ensuring the safety and stability of the structure.

[0029] In this embodiment, the limiting member 23 is a limiting end plate, which is provided on the telescopic end surface of the screw rod 22. In other embodiments, the structure of the limiting member 23 can be any structure as long as it can achieve position limiting with the limiting sleeve 311. For example, it can also be set as a limiting sleeve 311 that is sleeved on the telescopic end of the screw rod 22.

[0030] Furthermore, the force spring 314 is in an unprestressed state in its initial position. When the bridge 6 is in a normal displacement state and the actual axial displacement of the ball screw 2 is less than the initial distance between the limit member 23 and the limit platform 3111, the force spring 314 is uncompressed, and the limiting force generated by the limiting energy dissipation component 3 is zero. At this time, the limiting energy dissipation component 3 does not operate. When the actual axial displacement of the ball screw 2 is greater than the initial distance between the limit member 23 and the limit platform 3111, it indicates that the bridge 6 has exceeded the displacement limit. At this time, the limit member 23 and the limit platform 3111 are in a limited position, and the limiting energy dissipation component 3 generates a limiting force proportional to the actual axial displacement of the ball screw 2, thereby self-adjusting the damping force according to the amplitude of the bridge 6, ensuring that the limiting device can move reliably in different states of the bridge 6 and ensuring the vibration reduction effect of the bridge 6.

[0031] Furthermore, the limiting force generated by the limiting energy dissipation component 3 and the actual axial displacement of the ball screw 2 satisfy the following relationship: (1) (2) (3) (4) in, is the limiting force generated by the limiting energy dissipation component 3, is the initial distance between the limiting member 23 and the limiting platform 3111, is the actual axial displacement of the ball screw 2, and the initial position of the limiter 23 of the ball screw 2 is set to 0. The positive and negative values ​​are used to distinguish the displacement direction of the limit device when it is under tension and compression. is the velocity direction of ball screw 2, is the ratio of the axial force converted by the ball screw 2 to the axial pressure exerted on the friction rotor 3121, is the stiffness of the force spring 314, is the axial force converted by ball screw 2, is the axial pressure on the friction rotor 3121. The limit sleeve 311 and the limit member 23 move together after contact, causing the force spring 314 to be compressed and increase the pressure. is the friction coefficient of the friction rotor 3121, is the number of friction surfaces of the friction rotor 3121, is the lead of ball screw 2, is the outer diameter of the friction rotor 3121, is the inner diameter of the friction rotor 3121.

[0032] From the above formulas (1) to (4), it can be seen that the device of the present invention is At this time, the limiting force generated by the limiting energy dissipation component 3 is directly related to the initial distance between the limiting member 23 and the limiting platform 3111, the stiffness of the force spring 314, the axial force converted by the ball screw 2, and the axial pressure on the friction rotor 3121. By adjusting the above parameters, the limiting force generated by the limiting energy dissipation component 3 can be flexibly and accurately adjusted, thereby further realizing effective energy dissipation and vibration reduction of the structure, and its operation is convenient and the adjustment reliability is high. At the same time, the direction of the limiting force generated by the limiting device and the speed direction of the ball screw 2 are directly related to the initial distance between the limiting member 23 and the limiting platform 3111, the stiffness of the force spring 314, the axial force converted by the ball screw 2, and the axial pressure on the friction rotor 3121. By adjusting the above parameters, the limiting force generated by the limiting energy dissipation component 3 can be flexibly and accurately adjusted, thereby further realizing effective energy dissipation and vibration reduction of the structure, and its operation is convenient and the adjustment reliability is high. Related, such as Figure 1 As shown, when the left end is fixed, the speed direction of the ball screw 2 When the speed direction of ball screw 2 is When it moves to the right, the limit device is under tension. At this time, the direction of the limit force generated by the limit device is to the left.

[0033] Furthermore, if Figure 1 As shown, one end of the limiting sleeve 311 is disposed between the outer sleeve 1 and the friction block 313, circumferentially limited by a limiting key and axially movable. The other end of the limiting sleeve 311 is circumferentially limited by a limiting key and axially movable on the corresponding friction block 313. Thus, while limiting the relative rotation between the friction block 313 and the limiting sleeve 311, the friction block 313 has axial freedom, and the limiting sleeve 311 can be relatively displaced, effectively compressing the force spring 314, ensuring reliable transmission of friction force and friction torque.

[0034] Furthermore, one end of the force spring 314 abuts or is fixedly connected to the friction block, and the other end of the force spring 314 abuts against the limit platform 3111. When one of the force springs 314 is compressed, the end of the other force spring 314 disengages from the friction block or the limit platform 3111, so that the disengaged force spring 314 is not subjected to force, ensuring that the limit device can operate effectively under tension and compression, and has a compact structure and occupies little space.

[0035] Preferably, the energy dissipation assembly further includes a second energy dissipation unit 32, which includes a conductor plate 321 and energy dissipation permanent magnets 322 arranged opposite each other. The energy dissipation permanent magnets 322 are arranged in an array, with the energy dissipation permanent magnets 322 disposed on the rotating friction sleeve 312 and the conductor plate 321 disposed on the outer sleeve 1. This compact layout and small footprint allow for integration with the first energy dissipation unit 31. This significantly enhances the vibration reduction effect of the position limiting device without increasing the space required for the position limiting device.

[0036] When the structure vibrates, the vibration is transmitted to the ball screw 2. At this time, the nut 21 of the ball screw 2 drives the rotating friction sleeve 312 to rotate. At this time, the energy-consuming permanent magnet 322 located in the rotating friction sleeve 312 rotates relative to the conductor plate 321, thereby cutting the magnetic flux lines and generating eddy currents in the conductor plate 321. The eddy currents generate an electromagnetic field with a polarity opposite to the magnetic field of the energy-consuming permanent magnet 322 itself. The two electromagnetic fields with opposite polarities hinder each other's movement, producing an eddy current damping effect, so that the structural vibration is converted into heat energy generated by the eddy current. The heat energy is dissipated through conduction through air, etc., thereby further ensuring the energy dissipation and vibration reduction of the structure. The structure is simple and compact. In other embodiments, the conductor plate 321 and the energy-consuming permanent magnet 322 can be installed interchangeably, that is, the conductor plate 321 can also be located on the rotating friction sleeve 312, and the energy-consuming permanent magnet 322 can also be located on the outer sleeve 1. It can be seen that the present invention adopts the combination of the first energy-consuming unit 31 and the second energy-consuming unit 32 to better achieve the vibration reduction control of the structure and better ensure the safe and reliable operation of the structure. At the same time, the first energy dissipation unit 31 of the present invention adopts a structure of friction energy dissipation and increased friction torque, and the second energy dissipation unit 32 adopts an eddy current non-friction vibration reduction structure for vibration reduction, which changes the vibration reduction structure and method of the existing limiting device, avoids the occurrence of contact wear, leakage and other phenomena of the existing limiting device, ensures the vibration reduction effect, and greatly improves the durability of the limiting device.

[0037] In this embodiment, the conductor plate 321 is made of a high-conductivity, non-ferromagnetic material (such as copper, aluminum, copper alloy, or aluminum alloy) to enhance the intensity of eddy currents within the conductor plate 321. The energy-dissipating permanent magnets 322 comprise a plurality of energy-dissipating permanent magnets 322 arranged axially and / or radially along the rotating friction sleeve 312, coaxially disposed with the rotating friction sleeve 312. The energy-dissipating permanent magnets 322 utilize a Halbach array, axially magnetized, and / or radially magnetized magnetic arrays. The thickness and length of the radial and axial magnetic poles in the energy-dissipating permanent magnets 322, as well as the total length of the magnetic array, can be adjusted based on the selected magnetic pole array and the desired braking force.

[0038] In this embodiment, the nut 21 of the ball screw 2 is axially limited in the outer sleeve 1 by the first thrust bearing 4, and the rotating friction sleeve 312 is installed in the outer sleeve 1 through the second thrust bearing 5 to ensure reliable and effective rotation of the ball screw 2 and the rotating friction sleeve 312.

[0039] like Figure 1 and 3 As shown, the present invention sets the displacement of the ball screw 2 to be positive and the speed direction to be positive when it moves to the right from its initial position, and the limiting force generated by the limiting energy dissipation component 3 to be negative; when the ball screw 2 moves to the left from its initial position, the displacement is negative and the speed direction is negative, and the limiting force generated by the limiting energy dissipation component 3 to be positive. Specifically: Figure 3 In the coordinates, the fourth quadrant is the situation where the ball screw 2 is pulled when it moves to the right from the initial position (0), that is, the limiter 23 moves from the initial distance Exercise to , The actual axial displacement of ball screw 2 is the preset limit stroke. With preset limit travel satisfy At this time, the movement speed of the ball screw 2 is positive, the limiting force on the external end of the ball screw 2 is negative, and the absolute value of the limiting force gradually increases with the displacement. At this time, the limiting device is in a tensile state and generates an adaptive energy-consuming limiting force with the displacement.

[0040] The second quadrant is the situation where the device is compressed when the ball screw 2 moves leftward from the initial position, that is, the limiter 23 moves from the initial distance Exercise to At this time, the movement speed of the end of the ball screw 2 is negative; the limiting force on the external end of the ball screw 2 is positive, and the limiting force gradually increases with the displacement. At this time, the limiting device is in a compressed state and generates an adaptive energy-consuming limiting force with the displacement.

[0041] The first quadrant is the situation where the ball screw 2 recovers from the rightmost limit position to the initial position, that is, the limit member 23 recovers from the initial position Exercise to At this point, the outer end of ball screw 2 moves at a negative speed, while the limiting force of limiting energy dissipation assembly 3 becomes positive and gradually decreases to zero. This allows the limiting device to return to its initial state as the vibration of the bridge 6 or other structure gradually weakens. This allows the limiting device to reliably and effectively return from a tensioned state to its initial state as the vibration of the bridge 6 or other structure gradually weakens.

[0042] The third quadrant is the situation where the ball screw 2 recovers from the leftmost limit position to the initial position, that is, the limit member 23 is Sports At this time, the outer end of the ball screw 2 moves at a positive speed, the limiting force of the limiting energy dissipation assembly 3 becomes negative, and the absolute value of the limiting force gradually decreases to zero. This allows the limiting device to return to its initial state as the vibration of the bridge 6 or other structure gradually weakens. This allows the limiting device to reliably and effectively return to its initial state from a compressed state as the vibration of the bridge 6 or other structure gradually weakens.

[0043] It can be seen that the limiting force generated by the limiting energy-dissipating component 3 of the present invention is opposite to the speed of the ball screw 2, and the limiting force generated by the limiting energy-dissipating component 3 is proportional to the absolute value of the actual axial displacement of the ball screw 2. The present invention can adjust the damping according to the vibration size of the controlled structure such as the bridge 6, and can effectively restore to the initial state, with high overall reliability and safety.

[0044] While the present invention has been described with reference to preferred embodiments, various modifications may be made and equivalent components may be substituted without departing from the scope of the present invention. In particular, the various technical features described in the various embodiments may be combined in any manner, provided no structural conflicts exist. The present invention is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.

Claims

1. A ball screw type limiting device, characterized in that: The invention comprises an outer sleeve, a ball screw arranged in the outer sleeve, and a limit energy dissipation component arranged between the ball screw and the outer sleeve, wherein the limit energy dissipation component comprises a limit sleeve that is limited by the telescopic end of the inner side of the ball screw, and two groups of first energy dissipation units respectively arranged at the two ends of the limit sleeve, the first energy dissipation unit comprising a rotating friction sleeve with a friction rotor, a friction block that is pressed against the friction rotor when the rotating friction sleeve rotates, and a force spring that presses the friction rotor when the friction block dissipates friction energy, the rotating friction sleeve is fixedly connected to the nut of the axially limited ball screw; the force spring is connected between the limit sleeve and the friction block.

2. The ball screw type limiting device according to claim 1, characterized in that: A limit piece is provided at the inner telescopic end of the screw of the ball screw, and limit platforms are provided at both ends of the limit sleeve for limiting the position of the limit piece. The sum of the initial distance between the limit piece and the limit platform and the maximum compression amount of the force spring is greater than or equal to the preset maximum displacement of the structure to be damped.

3. The ball screw type limiting device according to claim 2, characterized in that: The force spring is in an unprestressed state in the initial position. When the actual axial displacement of the ball screw is less than the initial distance between the limit member and the limit platform, the force spring is not compressed, and the limit force generated by the limit energy dissipation component is zero; when the actual axial displacement of the ball screw is greater than the initial distance between the limit member and the limit platform, the limit member and the limit platform are limitedly matched, and the limit energy dissipation component generates a limit force proportional to the actual axial displacement of the ball screw.

4. The ball screw type limiting device according to claim 3, characterized in that: The limiting force generated by the limiting energy dissipation component and the actual axial displacement of the ball screw satisfy the following relationship: in, The limiting force generated by the limiting energy-consuming component, is the initial distance between the limiter and the limit platform, is the actual axial displacement of the ball screw, is the velocity direction of the ball screw, It is the ratio of the axial force converted by the ball screw to the axial pressure exerted on the friction rotor. is the stiffness of the force spring, is the axial force converted by the ball screw, is the axial pressure on the friction rotor, is the friction coefficient of the friction rotor, is the number of friction surfaces of the friction rotor, is the lead of the ball screw, is the outer diameter of the friction rotor, is the inner diameter of the friction rotor.

5. The ball screw type limiting device according to any one of claims 2 to 4, characterized in that: One end of the limiting sleeve is arranged between the outer sleeve and the friction block through circumferential limitation and axial movement by a limiting key, and the other side end of the limiting sleeve is installed on the corresponding friction block through circumferential limitation and axial movement by a limiting key.

6. The ball screw type limiting device according to claim 5, characterized in that: One end of the force spring abuts or is fixedly connected to the friction block, and the other end of the force spring abuts against the limit platform. When one of the force springs is compressed, the end of the other force spring is separated from the friction block or the limit platform.

7. The ball screw type limiting device according to any one of claims 1 to 4, characterized in that: The energy dissipation component also includes a second energy dissipation unit, which includes a conductor plate and an energy dissipation permanent magnet arranged relatively to each other. The energy dissipation permanent magnets are arranged in an array. One of the conductor plate and the energy dissipation permanent magnet is provided on the rotating friction sleeve, and the other is provided on the outer sleeve.

8. The ball screw type limiting device according to any one of claims 1 to 4, characterized in that: The nut of the ball screw is axially limited in the outer sleeve by a first thrust bearing, and the rotating friction sleeve is installed in the outer sleeve by a second thrust bearing.

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