A self-resetting piezoelectric semi-active inerter damper

Abstract

The present invention belongs to the technical field of vibration control, and discloses a self-resetting piezoelectric semi-active inertial-damping device, which comprises a cylindrical body, a piezoelectric stack and a lead screw disposed in the cylindrical body. From left to right, a free plate, a friction plate, a fixed plate and a sliding plate are sequentially arranged on the cylindrical body. The free plate, the friction plate and the fixed plate are sleeved on the lead screw, the sliding plate is located at one end of the lead screw, a porous cylinder and a rotating block are also sleeved on the lead screw. The porous cylinder is located between the free plate and the friction plate, the rotating block is located between the friction plate and the fixed plate, the piezoelectric stack is located in the through hole of the porous cylinder, and the side of the fixed plate is fixed to the inner wall of the cylindrical body; A plurality of first SMA wire bundles are symmetrically fixed between the fixed plate and the sliding plate, and a plurality of second SMA wire bundles are symmetrically fixed between the sliding plate and the side wall of the cylindrical body. The present invention uses piezoelectric variable friction force to adjust the inertance coefficient in real time, and uses the tensile force of the SMA wire to achieve self-resetting, with a wider application range and better vibration reduction effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of vibration control and relates to a self - reset piezoelectric semi - active inertial mass damper. Background Art

[0002] The inertial mass is a new type of structural control element related to the accelerations at both ends. Compared with traditional vibration reduction, inertial mass vibration reduction can achieve flexible adjustment of inertia, frequency regulation, change the structural inertia while basically not changing the physical mass of the structure, and improve the energy - dissipation efficiency of energy - dissipating components in the inertial mass system. Therefore, inertial mass vibration reduction has become a research hotspot in the current vibration control field. Its vibration - reduction principle is mainly reflected in two aspects. On the one hand, the combination of an inertial mass and a spring can avoid resonance between the main structure and external excitation through frequency modulation. On the other hand, the vibration inside the inertial mass vibration - reduction system is not synchronized with the main structure, which can amplify the effective deformation of the energy - dissipating device inside the inertial mass system, realize energy - dissipation efficiency improvement and further suppress the dynamic response. The implementation forms of the inertial mass mechanism mainly include ball screw, rack and pinion, lever mechanism, and hydraulic type, etc. Currently, the ball screw mechanism is used more frequently. The inertial mass mechanism can effectively control the dynamic response of the structure and has good engineering application prospects. However, most of the currently designed inertial mass dampers have a fixed inertial mass coefficient. Before use, the rotating mass needs to be designed in advance according to the existing environment, with limited application range and no reset function.

[0003] The piezoelectric variable - friction damper is a displacement - type damper, and its energy - dissipation ability depends on the magnitude of the frictional displacement. The inertial mass mechanism can amplify the displacement of the damping element and has the dual functions of inertia and damping enhancement. If the ball - screw inertial mass mechanism is combined with the controllable variable - friction mechanism, it will greatly increase the rotational displacement of the piezoelectric variable - friction unit. At the same time, the adjustable frictional force generated by the electro - mechanical deformation of the piezoelectric actuator can change the resistance when the inertial flywheel rotates, realizing semi - active real - time adjustment of the inertial mass coefficient and further improving the damping effect and application range of the inertial mass system. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems that the inertial mass coefficient of the inertial mass damper cannot be adjusted and the actuating rod cannot be reset, and to provide a self - reset piezoelectric semi - active inertial mass damper. It uses piezoelectric variable frictional force to adjust the inertial mass coefficient in real - time and uses the tension of the SMA wire to achieve self - reset, with a wider application range and better damping effect.

[0005] To achieve the above - mentioned purpose, the present invention adopts the following technical solutions:

[0006] The present invention provides a self-resetting piezoelectric semi-active inertial damper, which includes a cylindrical body, a piezoelectric stack, and a lead screw penetrating through the cylindrical body. From left to right, the cylindrical body is sequentially provided with a free plate, a friction plate, a fixed plate, and a sliding plate. The free plate, the friction plate, and the fixed plate are penetrated by the lead screw. The sliding plate is located at one end of the lead screw. A porous cylinder and a rotating block are also penetrated by the lead screw. The porous cylinder is located between the free plate and the friction plate, and the rotating block is located between the friction plate and the fixed plate. The piezoelectric stack is located in the through hole of the porous cylinder, and the side of the fixed plate is fixed to the inner wall of the cylindrical body;

[0007] A plurality of first SMA wire bundles are symmetrically fixed between the fixed plate and the sliding plate, and a plurality of second SMA wire bundles are symmetrically fixed between the sliding plate and the side wall of the cylindrical body.

[0008] In one technical solution, the length of the piezoelectric stack is greater than the length of the through hole of the porous cylinder, and the end face of the piezoelectric stack contacts the free plate.

[0009] In one technical solution, a plurality of first guiding and limiting holes are symmetrically formed in the circumferential direction on the side wall of the cylindrical body corresponding to the friction plate, and a plurality of second guiding and limiting holes are symmetrically formed in the circumferential direction on the side wall of the cylindrical body corresponding to the sliding plate; fixing blocks are arranged in both the first guiding and limiting holes and the second guiding and limiting holes. The fixing blocks are in clearance fit with the first guiding and limiting holes and the second guiding and limiting holes respectively, and one end of the fixing block is embedded in the friction plate or the sliding plate.

[0010] In one technical solution, the side of the fixed plate is fixed to the inner wall of the cylindrical body through an embedded fixing block, and a thrust ball bearing is fixed on one side of the fixing block. One end of the thrust ball bearing contacts the rotating block.

[0011] In one technical solution, a pre-tightening bolt is penetrated through the side wall of the cylindrical body near the free plate, and the pre-tightening bolt contacts the free plate.

[0012] In one technical solution, the cylindrical body, the free plate, the friction plate, the fixed plate, and the porous cylinder are all in clearance fit with the lead screw, and the rotating block rotates around the lead screw through a ball nut arranged at its center.

[0013] In one technical solution, both the first SMA wire bundle and the second SMA wire bundle are composed of a plurality of nickel-titanium shape memory alloy wires.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] The free plate, porous cylinder, piezoelectric stack and rotating block of the present invention form a semi-active inertia capacitance unit, and the fixed plate, sliding plate, cylindrical body, first SMA wire bundle and second SMA wire bundle form an SMA energy dissipation and reset unit. Due to the movement of the friction plate, the piezoelectric stack is compressed and undergoes electrostrictive deformation after applying a voltage. At the same time, with the relative positions of the free plate and the fixed plate unchanged, the left or right movement of the friction plate changes the normal pressure between it and the rotating block, that is, changes the resistance received by the rotating block during rotation, realizing the semi-active adjustment of the inertia capacitance coefficient; when the lead screw deviates from the initial position to the left or right, the restoring force of the first SMA wire bundle or the second SMA wire bundle can reset it.

[0016] The structure of the present invention is simple, the force transmission is clear, the inertia capacitance coefficient is adjustable, the structure can be reset, the applicable range is wider, and the vibration reduction performance is better. Brief Description of the Drawings

[0017] Figure 1 is the main sectional structure schematic diagram of a self-resetting piezoelectric semi-active inertia capacitance damper of the present invention;

[0018] Figure 2 is the top view structure schematic diagram of a self-resetting piezoelectric semi-active inertia capacitance damper of the present invention;

[0019] Figure 3 is the present invention Figure 1 The sectional structure schematic diagram of A-A in it.

[0020] Figure 4 is the present invention Figure 1 The sectional structure schematic diagram of B-B in it.

[0021] Reference numerals in the drawings: 1 is a cylindrical body, 2 is a lead screw, 3 is a pre-tightening bolt, 4 is a free plate, 5 is a porous cylinder, 6 is a piezoelectric stack, 7 is a friction plate, 8 is a rotating block, 9 is a thrust ball bearing, 10 is a fixed plate, 11 is a first SMA wire bundle, 12 is a second SMA wire bundle, 13 is a sliding plate, 14 is a connecting piece, 15 is a first guiding and limiting hole, 16 is a second guiding and limiting hole, 17 is a fixing block. Detailed Embodiments

[0022] The following embodiments are used to illustrate the present invention, but are not used to limit the protection scope of the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. The test methods in the following embodiments are conventional methods unless otherwise specified.

[0023] Embodiment 1

[0024] As Figures 1 to 4As shown in the figure, a self-resetting piezoelectric semi-active inertial capacitance damper of the present invention includes a cylindrical body 1, a piezoelectric stack 6, and a lead screw 2 passing through the cylindrical body 1. From left to right, the cylindrical body 1 is further sequentially provided with a free plate 4, a friction plate 7, a fixed plate 10, and a sliding plate 13. The free plate 4, the friction plate 7, and the fixed plate 10 are sleeved on the lead screw 2. The sliding plate 13 is located at one end of the lead screw 2. A porous cylinder 5 and a rotating block 8 are also sleeved on the lead screw 2. The porous cylinder 5 is located between the free plate 4 and the friction plate 7, and the rotating block 8 is located between the friction plate 7 and the fixed plate 10. The piezoelectric stack 6 is located in the through hole of the porous cylinder 5. The side of the fixed plate 10 is fixed to the inner wall of the cylindrical body 1. As Figure 4 shown, the piezoelectric stacks 6 are symmetrically arranged in the porous cylinder 5 to balance the force of piezoelectric electro-deformation. And the length of the piezoelectric stack 6 is greater than the length of the through hole of the porous cylinder 5, so that the end face of the piezoelectric stack 6 contacts the free plate 4 to ensure that the piezoelectric stack 6 can be effectively applied with pressure.

[0025] As Figure 1 shown, a plurality of first SMA wire bundles 11 are symmetrically fixed between the fixed plate 10 and the sliding plate 13, and a plurality of second SMA wire bundles 12 are symmetrically fixed between the sliding plate 13 and the side wall of the cylindrical body 1. In one embodiment, both the first SMA wire bundle 11 and the second SMA wire bundle 12 are composed of a plurality of nickel-titanium shape memory alloy wires, and their diameters, quantities, and effective lengths are equal to ensure equal forces on both sides. The specific quantity, diameter, and length can be set according to needs.

[0026] As Figure 1 shown, a plurality of first guiding and limiting holes 15 are symmetrically formed in the circumferential direction on the side wall of the cylindrical body 1 corresponding to the friction plate 7, and a plurality of second guiding and limiting holes 16 are symmetrically formed in the circumferential direction on the side wall of the cylindrical body 1 corresponding to the sliding plate 13; fixing blocks 17 are arranged in both the first guiding and limiting holes 15 and the second guiding and limiting holes 16. The fixing blocks 17 are in clearance fit with the first guiding and limiting holes 15 and the second guiding and limiting holes 16 respectively. One end of the fixing block 17 is embedded in the friction plate 7 or the sliding plate 13 to limit its rotation.

[0027] As Figure 1 shown, the side of the fixed plate 10 is fixed to the inner wall of the cylindrical body 1 through the embedded fixing block 17, and the fixed plate 10 cannot rotate. A thrust ball bearing 9 is also fixed on one side of the fixing block 10. One end of the thrust ball bearing 9 contacts the rotating block 8. In this way, after the rotating block 8 rotates, it can drive the thrust ball bearing 9 on its right side to rotate, so that only the left side of the rotating block 8 forms friction with the friction plate 7, thereby realizing the single-sided friction energy dissipation between the rotating block 8 and the friction plate 7.

[0028] As Figure 1As shown in the figure, a pre-tightening bolt 3 is inserted through the side wall of the cylindrical body 1 near one side of the free plate 4. The pre-tightening bolt 3 contacts the free plate 4. On the one hand, it prevents the free plate 4 from colliding with the wall of the cylindrical body 1 during the movement. On the other hand, it ensures the application of pressure to the free plate 4 and the uniform force on the piezoelectric stack 6.

[0029] In one embodiment, the cylindrical body 1, the free plate 4, the friction plate 7, the fixing plate 10, and the porous cylinder 5 are all in clearance fit with the lead screw 2. The rotating block 8 rotates around the lead screw 2 through a ball nut provided at its center. The rotating block 8 forms a rotating friction surface with the friction plate 7, and realizes friction energy dissipation and inertance coefficient adjustment by means of the electrostrictive deformation of the piezoelectric stack 6. At the same time, the ball nut and the lead screw 2 form a rotating pair, converting the linear motion of the lead screw 2 into the rotation of the rotating block 8. In this way, the free plate 4 can move left and right and rotate around the lead screw 2. The friction plate 7 can move left and right along the first guiding and limiting hole 15 but is restricted by the fixing block 17 and cannot rotate around the lead screw 2. The fixing plate 10 cannot move left and right and is restricted by the fixing block 17 and cannot rotate around the lead screw 2. The sliding plate 13 can move left and right along the second guiding and limiting hole 16 but is restricted by the fixing block 17 and cannot rotate around the lead screw 2. With the cooperation of each component, the self-reset of the damper and the semi-active adjustment of the inertance coefficient can be realized.

[0030] The working principle of the self-resetting piezoelectric semi-active inertance damper of the present invention is as follows: When vibration occurs, whether the lead screw 2 moves to the left or to the right, the rotating block 8 rotates, generating a rotating frictional force with the friction plate 7. Due to the movement of the friction plate 7, the piezoelectric stack 6 in contact with the free plate 4 is compressed and undergoes electrostrictive deformation after applying a voltage. At the same time, with the relative positions of the free plate 4 and the fixing plate 10 remaining unchanged, the left or right movement of the friction plate 7 changes its normal pressure with the rotating block 8, that is, changes the resistance received by the rotating block 8 during rotation, realizing the semi-active adjustment of the inertance coefficient. At the same time, with the relative positions of the fixing plate 10 and the cylindrical body 1 remaining unchanged, the lead screw 2 drives the sliding plate 13 to move left or right, and the first SMA wire bundle 11 or the second SMA wire bundle 12 is alternately tensioned for energy dissipation and resets the lead screw 2 after vibration. The present invention realizes the double enhancement of inertial mass and friction energy dissipation, and at the same time, the SMA wire bundle can also dissipate energy.

[0031] The above-mentioned embodiments are only the preferred embodiments of the present invention, which are only used to explain the present invention and do not limit the scope of implementation of the present invention. For those skilled in the art of this technology, of course, according to the technical content disclosed in this specification, other implementation manners can be easily made by means of replacement or change. Therefore, all changes and improvements made on the principle of the present invention should be included within the scope of the patent application of the present invention.

Claims

1. A self-resetting piezoelectric semi-active inertance damper, comprising a cylindrical body (1), a piezoelectric stack (6) and a lead screw (2) arranged in the cylindrical body (1), characterized in that, The cylindrical body (1) is further sequentially provided with a free plate (4), a friction plate (7), a fixing plate (10) and a sliding plate (13) from left to right. The free plate (4), the friction plate (7) and the fixing plate (10) are arranged on the lead screw (2). The sliding plate (13) is located at one end of the lead screw (2). A porous cylinder (5) and a rotating block (8) are also arranged on the lead screw (2). The porous cylinder (5) is located between the free plate (4) and the friction plate (7), and the rotating block (8) is located between the friction plate (7) and the fixing plate (10). The piezoelectric stack (6) is located in the through hole of the porous cylinder (5). The side of the fixing plate (10) is fixed to the inner wall of the cylindrical body (1). A plurality of first SMA wire bundles (11) are symmetrically fixed between the fixing plate (10) and the sliding plate (13), and a plurality of second SMA wire bundles (12) are symmetrically fixed between the sliding plate (13) and the side wall of the cylindrical body (1).

2. The self-resetting piezoelectric semi-active inerter damper according to claim 1, wherein The length of the piezoelectric stack (6) is greater than the length of the through hole of the porous cylinder (5), and the end face of the piezoelectric stack (6) contacts the free plate (4).

3. The self-resetting piezoelectric semi-active inerter damper according to claim 1, wherein A plurality of first guiding and limiting holes (15) are symmetrically formed in the circumferential direction on the side wall of the cylindrical body (1) corresponding to the friction plate (7), and a plurality of second guiding and limiting holes (16) are symmetrically formed in the circumferential direction on the side wall of the cylindrical body (1) corresponding to the sliding plate (13). Fixing blocks (17) are arranged in both the first guiding and limiting holes (15) and the second guiding and limiting holes (16). The fixing blocks (17) are in clearance fit with the first guiding and limiting holes (15) and the second guiding and limiting holes (16) respectively. One end of the fixing block (17) is embedded in the friction plate (7) or the sliding plate (13).

4. The self-resetting piezoelectric semi-active inerter damper according to claim 3, characterized in that, The side of the fixing plate (10) is fixed to the inner wall of the cylindrical body (1) through the embedded fixing block (17). A thrust ball bearing (9) is also fixed on one side of the fixing plate (10), and one end of the thrust ball bearing (9) contacts the rotating block (8).

5. A self-resetting piezoelectric semi-active inerter damper according to claim 1, characterized in that, A pre-tightening bolt (3) is arranged on the side wall of the cylindrical body (1) near the free plate (4), and the pre-tightening bolt (3) contacts the free plate (4).

6. The self-resetting piezoelectric semi-active inerter damper according to claim 1, wherein, The cylindrical body (1), the free plate (4), the friction plate (7), the fixing plate (10) and the porous cylinder (5) are all in clearance fit with the lead screw (2). The rotating block (8) rotates around the lead screw (2) through a ball nut arranged at its center.

7. A self-resetting piezoelectric semi-active inertance damper according to claim 1, characterized in that, Both the first SMA wire bundles (11) and the second SMA wire bundles (12) are composed of a plurality of nickel-titanium shape memory alloy wires.

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