A miniature exciter

Abstract

The application discloses a micro exciter and particularly relates to the field of exciter, which comprises a power system and an exciter body, wherein the exciter body comprises a vertical rod, a frame, an upper swing rod and a lower swing rod, the frame comprises an extension pipe and a connecting frame, and the extension pipe and the connecting frame are connected through interference fit. The application utilizes a direct-acting slide rod mechanism to convert force by 90 degrees, adopts a dead point prevention swing rod design with a motion center line not coinciding with an axis, and constructs two coaxial cylinders, i.e. the extension pipe and the connecting frame, to form the frame of the exciter. The frame can assemble various parts of the exciter, fix the exciter when the exciter works in the interior of a rod, and place the exciter at different positions in a pipe by increasing the extension pipe. The radial dimension is small enough and the exciter can normally work in dry and wet working conditions, and the exciter can apply step excitation to the rod, so that the dry and wet modes of the rod can be more accurately obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of vibrators, and more particularly, to a micro vibrator. Background Art

[0002] When a fluid flows through a solid, it exerts alternating fluid forces on the solid surface, causing the solid to reciprocate. The reciprocating motion of the solid in turn changes the fluid flow pattern, which in turn changes the fluid forces acting on the solid surface. This phenomenon of fluid-solid interaction is flow-induced vibration. Flow-induced vibration will eventually overlap with the structural modes, generating resonance, causing structural deformation and dynamic stress, and even damage. Therefore, measuring modes (modes are the natural vibration characteristics of a structural system. The free vibration of a linear system can be decoupled into N orthogonal single-degree-of-freedom vibration systems, corresponding to the N modes of the system. Each mode has a specific natural frequency, damping ratio, and modal shape. These modal parameters can be obtained by calculation or experimental analysis) plays a vital role in the research of flow-induced vibration and in avoiding flow-induced vibration damage.

[0003] In nuclear power systems, it is essential to study the wear characteristics of fuel elements and steam generator heat transfer tubes caused by flow-induced vibration. The structural stability of both is crucial to the safe operation of the nuclear power system. For example, the heat transfer tube bundles in each circuit of a nuclear power plant are often subjected to uneven crossflow, which can cause flow-induced vibrations, leading to damage such as collisions, wear, and fatigue. These damages can affect the availability and service life of the equipment and even cause nuclear accidents. The two aforementioned elements have small radial dimensions, making it impossible to install existing micro-vibrators inside them. If excitation is applied from the outside of the rod, it will interfere with the flow field around the rod, thereby affecting the accuracy of the modal frequency measurement results. Therefore, there is an urgent need for an exciter that can be installed inside the rod to provide step excitation.

[0004] As a tool for providing excitation, a micro-vibrator performs a series of mechanical movements within a small space, applying force to an object to generate excitation. This can be used to study basic properties such as the object's modal state. Since the difficulty of mechanical processing increases with the size of the structure, the most common micro-vibrator currently used is an electromagnetic vibrator, which uses the principle of electromagnetic induction to generate excitation. This type of vibrator has the advantages of high frequency and easy control, but the excitation volume is not large enough, the cost is high, and it is prone to magnetic leakage. In some cases where the excitation frequency is not high, the electromagnetic micro-vibrator loses its advantages. Moreover, since it contains electronic components, it cannot measure the wet mode of the rod without the installation of waterproof equipment. Therefore, a new vibrator structure needs to be redesigned.

[0005] Chinese invention patent application publication number CN214347694U proposes a micro-vibrator, the structure of which includes an outer shell, a control board, a resonance generator, and an impedance head. The resonance generator includes a magnetizer, a surrounding coil, a spring, and a resonator. The top section of the raised ring wall of the resonator is suspended and built into the annular space of the magnetizer. Within the annular space of the magnetizer, a surrounding coil is circumferentially arranged between the magnetizer and the resonator. A spring is arranged between the lower end surface of the outer wall cylinder of the magnetizer and the bottom plate outside the raised ring wall of the resonator. The center below the bottom plate of the resonator is connected to the impedance head through a column extending from the bottom of the outer shell. The invention can generate different excitation forces while adjusting the excitation frequency, and the excitation force and acceleration generated at the driving point can be directly obtained through the impedance head. At the same time, because the excitation equipment including the impedance head has been streamlined to a minimum, it can be easily installed in vibration tests with limited space, and excitation can be performed in special locations. While this invention achieves a smaller size, its complex internal structure limits its overall radial dimensions, preventing it from achieving a significant improvement in exciter volume compared to other micro-vibrators. Furthermore, because the control board is integrated within the excitation module, it is not suitable for operation in wet environments, such as those involving fluids. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a micro vibrator. The technical problem to be solved by the present invention is: to solve the problem that the existing vibrator has a large radial size and cannot be applied to small-sized pipes such as heat transfer tubes of steam generators in nuclear power systems, and is unstable in operation in a wet working environment.

[0007] To achieve the above-mentioned object, the present invention provides the following technical solution: a micro vibrator, comprising a power system and a vibrator body, wherein the vibrator body comprises a vertical rod, a frame, an upper swing rod, and a lower swing rod, wherein the frame comprises an extension tube and a connecting frame, wherein the extension tube and the connecting frame are connected by an interference fit;

[0008] The connecting frame is configured as a cylindrical shape, and a raised cylindrical boss is fixedly provided at the connecting end of the connecting frame and the extension tube. An inner hole is longitudinally provided at the center line of the cylindrical boss and the connecting frame. A rectangular groove having a width consistent with the diameter of the inner hole is transversely provided in the middle of the connecting frame, and a main body connecting hole is provided between the bottom end of the rectangular groove and the connecting frame.

[0009] The extension tube is set to be cylindrical, and a connecting boss is fixedly provided at one end of the extension tube away from the connecting frame. A through hole is longitudinally formed through the connecting boss and the extension tube. The through hole has the same inner diameter as the inner hole. A rear connecting groove is provided at one end of the extension tube close to the connecting frame.

[0010] In a preferred embodiment, the connecting boss and the cylindrical boss have the same size, and the extension tube and the connecting frame are connected by interference fit between the cylindrical boss and the connecting groove.

[0011] In a preferred embodiment, both ends of the upper swing rod are connected to the vertical rod and the lower swing rod respectively through pins, and the bottom end of the lower swing rod is connected to the main body connecting hole through a pin.

[0012] In a preferred embodiment, the vertical rod is configured as a round rod with an outer diameter smaller than the inner diameter of the through hole, and an end hole is provided at the connection between the bottom end of the vertical rod and the upper swing rod, the upper swing rod is configured as a rectangular parallelepiped with a width and thickness smaller than the inner hole diameter, and a first upper end hole is provided at the top end of the upper swing rod, and a first lower end hole is provided at the bottom end of the upper swing rod, and the center of the first lower end hole deviates from the axis of the upper swing rod.

[0013] In a preferred embodiment, the lower swing rod is configured as a rectangular parallelepiped whose width and thickness are both smaller than the inner hole diameter, a second upper end hole is opened at the connection between the top end of the lower swing rod and the upper swing rod, and a second lower end hole is opened at the bottom end of the lower swing rod, and the center of the second lower end hole deviates from the axis of the lower swing rod.

[0014] In a preferred embodiment, the terminal hole and the first upper hole are connected by a pin, the first lower hole and the second upper hole are connected by a pin, and the second lower hole and the main body connection hole are connected by a pin.

[0015] In a preferred embodiment, the power system includes a controller and a hydraulic rod, the controller is used for output control of the hydraulic rod, and the output end of the hydraulic rod is connected to the top end of the vertical rod.

[0016] The technical effects and advantages of the present invention are as follows:

[0017] 1. The present invention utilizes a linear slide mechanism to convert force by 90 degrees. The anti-dead-point rocker design, in which the line connecting the center of motion does not coincide with the axis, constructs two coaxial cylinders, namely an extension tube and a connecting frame, to form the frame of the exciter. This allows for both assembling the various parts of the exciter and fixing the exciter when it penetrates deep into the rod body. Furthermore, the exciter can be placed at different positions within the tube by adding an extension tube. The radial dimension is sufficiently small and the exciter can operate normally in both dry and wet working conditions. By applying step excitation to the rod body, the dry and wet modes of the rod body can be more accurately determined.

[0018] 2. The present invention greatly reduces the radial size of the vibrator by adopting a direct-acting sliding rod structure, and can be arranged to operate inside the rod structure, minimizing the impact on the rod mode; there are no electrical appliances in the tube, which meets the requirements of more complex environments; the relatively simple structure makes its cost lower than other micro vibrators while having good maintainability. Since this micro vibrator adopts a rigid structure for force transmission, it only needs to change the power system from reciprocating motion to continuous push through the program to apply a stable load to the object to be tested, so it can also be used as a pipeline radial load loading device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0020] Figure 2 It is a schematic diagram of the structure of the exciter body of the present invention.

[0021] Figure 3 It is a schematic structural diagram of the connecting frame of the present invention.

[0022] Figure 4 It is a schematic diagram of the cross-section structure of the extension tube of the present invention.

[0023] Figure 5 It is a structural schematic diagram of the connection state of the vertical rod, the upper swing rod and the lower swing rod of the present invention.

[0024] Figure 6 It is a schematic diagram of the vertical rod structure of the present invention.

[0025] Figure 7 It is a schematic structural diagram of the upper swing arm of the present invention.

[0026] Figure 8 It is a schematic structural diagram of the lower swing rod of the present invention.

[0027] Figure 9 It is the workflow diagram of the present invention.

[0028] The figures are marked as follows: 1 power system, 2 vertical rod, 3 frame, 4 upper swing rod, 5 lower swing rod, 6 extension tube, 7 connecting frame, 8 cylindrical boss, 9 inner hole, 10 rectangular groove, 11 main body connecting hole, 12 connecting boss, 13 through hole, 14 connecting groove, 15 end hole, 16 first upper end hole, 17 first lower end hole, 18 second upper end hole, 19 second lower end hole. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] The present invention provides Figure 1 A micro vibrator shown includes a power system 1 and a vibrator body. The vibrator body includes a pendulum rod 2, a frame 3, an upper swing rod 4, and a lower swing rod 5. The frame 3 includes an extension tube 6 and a connecting frame 7. The extension tube 6 and the connecting frame 7 are connected by an interference fit.

[0031] The connecting frame 7 is provided in a cylindrical shape, and a raised cylindrical boss 8 is fixedly provided at the connecting end of the connecting frame 7 and the extension tube 6. An inner hole 9 is longitudinally opened at the center line of the cylindrical boss 8 and the connecting frame 7. A rectangular groove 10 with a width consistent with the diameter of the inner hole 9 is transversely opened in the middle of the connecting frame 7, and a main body connecting hole 11 is opened between the bottom end of the rectangular groove 10 and the connecting frame 7;

[0032] The extension tube 6 is configured to be cylindrical, and a connecting boss 12 is fixedly provided at one end of the extension tube 6 away from the connecting frame 7. A through hole 13 is longitudinally penetrated through the connecting boss 12 and the extension tube 6. The through hole 13 has the same inner diameter as the inner hole 9. A rear connecting groove 14 is provided at one end of the extension tube 6 close to the connecting frame 7.

[0033] The connecting boss 12 is consistent in size with the cylindrical boss 8, and the extension tube 6 and the connecting frame 7 are connected by an interference fit between the cylindrical boss 8 and the connecting groove 14;

[0034] The two ends of the upper swing rod 4 are respectively connected to the vertical rod 2 and the lower swing rod 5 by pins, and the bottom end of the lower swing rod 5 is connected to the main body connection hole 11 by a pin; the vertical rod 2 is set to a round rod with an outer diameter smaller than the inner diameter of the through hole 13, and an end hole 15 is opened at the connection between the bottom end of the vertical rod 2 and the upper swing rod 4, the upper swing rod 4 is set to a rectangular parallelepiped with a width and thickness smaller than the diameter of the inner hole 9, and a first upper end hole 16 is opened at the top of the upper swing rod 4, and a first lower end hole 17 is opened at the bottom end of the upper swing rod 4. The first lower end hole 17 The center deviates from the axis of the upper swing rod 4; the lower swing rod 5 is configured as a rectangular parallelepiped with a width and thickness both smaller than the diameter of the inner hole 9; a second upper end hole 18 is opened at the connection between the top of the lower swing rod 5 and the upper swing rod 4, and a second lower end hole 19 is opened at the bottom of the lower swing rod 5, and the center of the second lower end hole 19 deviates from the axis of the lower swing rod 5; the terminal hole 15 and the first upper end hole 16 are connected by a pin, the first lower end hole 17 and the second upper end hole 18 are connected by a pin, and the second lower end hole 19 and the main body connection hole 11 are connected by a pin;

[0035] The power system 1 includes a controller and a hydraulic rod. The controller is used for output control of the hydraulic rod. The output end of the hydraulic rod is connected to the top end of the vertical rod 2.

[0036] like Figure 1-9 As shown, the specific implementation is:

[0037] like Figure 2 As shown, the frame 3 is divided into an extension tube 6 and a connecting frame 7. Figure 2 As shown; the extension tube 6 and the connecting frame 7 are combined by a section of interference fit connection port, such as Figure 3 and 4 As shown;

[0038] like Figure 7 and Figure 8 As shown, the first lower end hole 17 of the upper swing link 4 and the second upper end hole 18 of the lower swing link 5 are not located on the axis. When the swing link is fully retracted, the axis of the upper swing link 4 and the lower swing link 5 coincide and the line connecting the centers of motion cannot form a straight line, ensuring that the mechanism does not enter a dead point position and prevent jamming.

[0039] like Figure 5 As shown, the end hole 15 of the vertical rod 2 and the first upper end hole 16, the first lower end hole 17 and the second upper end hole 18, the second lower end hole 19 and the main body connection hole 11 are all connected by pins, thereby being fixed to the frame 3;

[0040] Combined process Figure 9 When the micro-vibrator starts working, the axial downward force generated by the hydraulic rod is transmitted through the vertical rod 2 and loaded onto the upper pendulum rod 4 and the lower pendulum rod 5. This structure converts the axial motion into a planar swing, which hits the object to be measured during the swing, forming a radial impact force. Then the hydraulic rod retracts, generating an axial upward tension, pulling the upper pendulum rod 4 and the lower pendulum rod 5 back to their initial positions. Within one cycle, the reciprocating motion of the hydraulic rod generates an instantaneous impact, giving the object to be measured one vibration. When a stable load is applied, the hydraulic rod will only generate an axial downward force, and the upper pendulum rod 4 and the lower pendulum rod 5 will continue to press against the object to be measured. To generate a stable radial load, the traditional mechanical exciter is miniaturized and split into two major parts: active and transmission. Each part works in conjunction to complete each step of the action, thereby achieving excitation; the active part, namely the power system 1, drives the vertical rod 2 and the rocker arm through a high-speed hydraulic rod to achieve periodic excitation, and the excitation intensity and frequency can be controlled by the controller; the transmission part, consisting of two rocker arms and the vertical rod 2, converts the axial power transmitted from the active part into swinging, and after hitting the object to be tested, the swinging force is converted into radial impact force, thereby transmitting the excitation to the object to be tested and achieving excitation of the object.

[0041] Finally, a few points should be explained: First, in the description of this application, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense, and may refer to mechanical or electrical connections, internal communication between two components, or direct connection. "Up," "down," "left," and "right" are only used to indicate relative positional relationships. When the absolute positions of the objects being described change, the relative positional relationships may also change.

[0042] Secondly: The drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention. Other structures may refer to conventional designs. The same embodiment and different embodiments of the present invention may be combined with each other without conflict.

[0043] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A micro vibrator, comprising a power system (1) and a vibrator body, characterized in that: The exciter body comprises a vertical rod (2), a frame (3), an upper swing rod (4) and a lower swing rod (5), wherein the frame (3) comprises an extension tube (6) and a connecting frame (7), and the extension tube (6) and the connecting frame (7) are connected by an interference fit; The connecting frame (7) is configured to be cylindrical, and a protruding cylindrical boss (8) is fixedly provided at the connecting end of the connecting frame (7) and the extension tube (6), an inner hole (9) is longitudinally provided at the center line of the cylindrical boss (8) and the connecting frame (7), a rectangular groove (10) having a width consistent with the diameter of the inner hole (9) is transversely provided in the middle of the connecting frame (7), and a main body connecting hole (11) is provided between the bottom end of the rectangular groove (10) and the connecting frame (7); The extension tube (6) is configured to be cylindrical, and a connecting boss (12) is fixedly provided at one end of the extension tube (6) away from the connecting frame (7), a through hole (13) is longitudinally penetrated through the connecting boss (12) and the extension tube (6), and the inner diameter of the through hole (13) is equal to that of the inner hole (9), and a rear connecting groove (14) is provided at one end of the extension tube (6) close to the connecting frame (7); The connecting boss (12) and the cylindrical boss (8) have the same size, and the extension tube (6) and the connecting frame (7) are connected by interference fit between the cylindrical boss (8) and the connecting groove (14); The two ends of the upper swing rod (4) are respectively connected to the vertical rod (2) and the lower swing rod (5) through pins, and the bottom end of the lower swing rod (5) is connected to the main body connection hole (11) through a pin.

2. A micro vibrator according to claim 1, characterized in that: The vertical rod (2) is configured as a round rod with an outer diameter smaller than the inner diameter of the through hole (13), and a terminal hole (15) is provided at the connection between the bottom end of the vertical rod (2) and the upper swing rod (4). The upper swing rod (4) is configured as a rectangular parallelepiped with a width and thickness smaller than the diameter of the inner hole (9), and a first upper end hole (16) is provided at the top end of the upper swing rod (4), and a first lower end hole (17) is provided at the bottom end of the upper swing rod (4), and the center of the first lower end hole (17) deviates from the axis of the upper swing rod (4).

3. The micro vibrator according to claim 2, characterized in that: The lower swing rod (5) is configured as a rectangular parallelepiped with a width and thickness both smaller than the diameter of the inner hole (9). A second upper end hole (18) is provided at the connection between the top end of the lower swing rod (5) and the upper swing rod (4). A second lower end hole (19) is provided at the bottom end of the lower swing rod (5). The center of the second lower end hole (19) deviates from the axis of the lower swing rod (5).

4. The micro vibrator according to claim 3, characterized in that: The end hole (15) and the first upper end hole (16) are connected by a pin, the first lower end hole (17) and the second upper end hole (18) are connected by a pin, and the second lower end hole (19) and the main body connection hole (11) are connected by a pin.

5. The micro vibrator according to claim 1, characterized in that: The power system (1) comprises a controller and a hydraulic rod, wherein the controller is used for output control of the hydraulic rod, and the output end of the hydraulic rod is connected to the top end of the vertical rod (2).

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